Merge master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 into next

.gitignore

@@ -3,6 +3,10 @@
 # subdirectories here. Add them in the ".gitignore" file
 # in that subdirectory instead.
 #
+# NOTE! Please use 'git-ls-files -i --exclude-standard'
+# command after changing this file, to see if there are
+# any tracked files which get ignored after the change.
+#
 # Normal rules
 #
 .*
@@ -18,18 +22,21 @@
 *.lst
 *.symtypes
 *.order
+*.elf
+*.bin
+*.gz
 
 #
 # Top-level generic files
 #
 tags
 TAGS
-vmlinux*
-!vmlinux.lds.S
+vmlinux
 System.map
 Module.markers
 Module.symvers
 !.gitignore
+!.mailmap
 
 #
 # Generated include files
@@ -52,8 +59,8 @@ series
 
 # cscope files
 cscope.*
+ncscope.*
 
 *.orig
-*.rej
 *~
 \#*#

CREDITS

@@ -2611,8 +2611,9 @@ S: Perth, Western Australia
 S: Australia
 
 N: Miguel Ojeda Sandonis
-E: maxextreme@gmail.com
-W: http://maxextreme.googlepages.com/
+E: miguel.ojeda.sandonis@gmail.com
+W: http://miguelojeda.es
+W: http://jair.lab.fi.uva.es/~migojed/
 D: Author of the ks0108, cfag12864b and cfag12864bfb auxiliary display drivers.
 D: Maintainer of the auxiliary display drivers tree (drivers/auxdisplay/*)
 S: C/ Mieses 20, 9-B

Documentation/ABI/testing/sysfs-block

@@ -26,3 +26,37 @@ Description:
 		I/O statistics of partition <part>. The format is the
 		same as the above-written /sys/block/<disk>/stat
 		format.
+
+
+What:		/sys/block/<disk>/integrity/format
+Date:		June 2008
+Contact:	Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+		Metadata format for integrity capable block device.
+		E.g. T10-DIF-TYPE1-CRC.
+
+
+What:		/sys/block/<disk>/integrity/read_verify
+Date:		June 2008
+Contact:	Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+		Indicates whether the block layer should verify the
+		integrity of read requests serviced by devices that
+		support sending integrity metadata.
+
+
+What:		/sys/block/<disk>/integrity/tag_size
+Date:		June 2008
+Contact:	Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+		Number of bytes of integrity tag space available per
+		512 bytes of data.
+
+
+What:		/sys/block/<disk>/integrity/write_generate
+Date:		June 2008
+Contact:	Martin K. Petersen <martin.petersen@oracle.com>
+Description:
+		Indicates whether the block layer should automatically
+		generate checksums for write requests bound for
+		devices that support receiving integrity metadata.

Documentation/ABI/testing/sysfs-bus-css

@@ -0,0 +1,35 @@
+What:		/sys/bus/css/devices/.../type
+Date:		March 2008
+Contact:	Cornelia Huck <cornelia.huck@de.ibm.com>
+		linux-s390@vger.kernel.org
+Description:	Contains the subchannel type, as reported by the hardware.
+		This attribute is present for all subchannel types.
+
+What:		/sys/bus/css/devices/.../modalias
+Date:		March 2008
+Contact:	Cornelia Huck <cornelia.huck@de.ibm.com>
+		linux-s390@vger.kernel.org
+Description:	Contains the module alias as reported with uevents.
+		It is of the format css:t<type> and present for all
+		subchannel types.
+
+What:		/sys/bus/css/drivers/io_subchannel/.../chpids
+Date:		December 2002
+Contact:	Cornelia Huck <cornelia.huck@de.ibm.com>
+		linux-s390@vger.kernel.org
+Description:	Contains the ids of the channel paths used by this
+		subchannel, as reported by the channel subsystem
+		during subchannel recognition.
+		Note: This is an I/O-subchannel specific attribute.
+Users:		s390-tools, HAL
+
+What:		/sys/bus/css/drivers/io_subchannel/.../pimpampom
+Date:		December 2002
+Contact:	Cornelia Huck <cornelia.huck@de.ibm.com>
+		linux-s390@vger.kernel.org
+Description:	Contains the PIM/PAM/POM values, as reported by the
+		channel subsystem when last queried by the common I/O
+		layer (this implies that this attribute is not neccessarily
+		in sync with the values current in the channel subsystem).
+		Note: This is an I/O-subchannel specific attribute.
+Users:		s390-tools, HAL

Documentation/ABI/testing/sysfs-class-bdi

@@ -14,6 +14,10 @@ MAJOR:MINOR
 	non-block filesystems which provide their own BDI, such as NFS
 	and FUSE.
 
+MAJOR:MINOR-fuseblk
+
+	Value of st_dev on fuseblk filesystems.
+
 default
 
 	The default backing dev, used for non-block device backed

Documentation/ABI/testing/sysfs-firmware-acpi

@@ -29,46 +29,46 @@ Description:
 
 		$ cd /sys/firmware/acpi/interrupts
 		$ grep . *
-		error:0
-		ff_gbl_lock:0
-		ff_pmtimer:0
-		ff_pwr_btn:0
-		ff_rt_clk:0
-		ff_slp_btn:0
-		gpe00:0
-		gpe01:0
-		gpe02:0
-		gpe03:0
-		gpe04:0
-		gpe05:0
-		gpe06:0
-		gpe07:0
-		gpe08:0
-		gpe09:174
-		gpe0A:0
-		gpe0B:0
-		gpe0C:0
-		gpe0D:0
-		gpe0E:0
-		gpe0F:0
-		gpe10:0
-		gpe11:60
-		gpe12:0
-		gpe13:0
-		gpe14:0
-		gpe15:0
-		gpe16:0
-		gpe17:0
-		gpe18:0
-		gpe19:7
-		gpe1A:0
-		gpe1B:0
-		gpe1C:0
-		gpe1D:0
-		gpe1E:0
-		gpe1F:0
-		gpe_all:241
-		sci:241
+		error:	     0
+		ff_gbl_lock:	   0   enable
+		ff_pmtimer:	  0  invalid
+		ff_pwr_btn:	  0   enable
+		ff_rt_clk:	 2  disable
+		ff_slp_btn:	  0  invalid
+		gpe00:	     0	invalid
+		gpe01:	     0	 enable
+		gpe02:	   108	 enable
+		gpe03:	     0	invalid
+		gpe04:	     0	invalid
+		gpe05:	     0	invalid
+		gpe06:	     0	 enable
+		gpe07:	     0	 enable
+		gpe08:	     0	invalid
+		gpe09:	     0	invalid
+		gpe0A:	     0	invalid
+		gpe0B:	     0	invalid
+		gpe0C:	     0	invalid
+		gpe0D:	     0	invalid
+		gpe0E:	     0	invalid
+		gpe0F:	     0	invalid
+		gpe10:	     0	invalid
+		gpe11:	     0	invalid
+		gpe12:	     0	invalid
+		gpe13:	     0	invalid
+		gpe14:	     0	invalid
+		gpe15:	     0	invalid
+		gpe16:	     0	invalid
+		gpe17:	  1084	 enable
+		gpe18:	     0	 enable
+		gpe19:	     0	invalid
+		gpe1A:	     0	invalid
+		gpe1B:	     0	invalid
+		gpe1C:	     0	invalid
+		gpe1D:	     0	invalid
+		gpe1E:	     0	invalid
+		gpe1F:	     0	invalid
+		gpe_all:    1192
+		sci:	1194
 
 		sci - The total number of times the ACPI SCI
 		has claimed an interrupt.
@@ -89,6 +89,13 @@ Description:
 
 		error - an interrupt that can't be accounted for above.
 
+		invalid: it's either a wakeup GPE or a GPE/Fixed Event that
+			doesn't have an event handler.
+
+		disable: the GPE/Fixed Event is valid but disabled.
+
+		enable: the GPE/Fixed Event is valid and enabled.
+
 		Root has permission to clear any of these counters.  Eg.
 		# echo 0 > gpe11
 
@@ -97,3 +104,43 @@ Description:
 
 		None of these counters has an effect on the function
 		of the system, they are simply statistics.
+
+		Besides this, user can also write specific strings to these files
+		to enable/disable/clear ACPI interrupts in user space, which can be
+		used to debug some ACPI interrupt storm issues.
+
+		Note that only writting to VALID GPE/Fixed Event is allowed,
+		i.e. user can only change the status of runtime GPE and
+		Fixed Event with event handler installed.
+
+		Let's take power button fixed event for example, please kill acpid
+		and other user space applications so that the machine won't shutdown
+		when pressing the power button.
+		# cat ff_pwr_btn
+		0
+		# press the power button for 3 times;
+		# cat ff_pwr_btn
+		3
+		# echo disable > ff_pwr_btn
+		# cat ff_pwr_btn
+		disable
+		# press the power button for 3 times;
+		# cat ff_pwr_btn
+		disable
+		# echo enable > ff_pwr_btn
+		# cat ff_pwr_btn
+		4
+		/*
+		 * this is because the status bit is set even if the enable bit is cleared,
+		 * and it triggers an ACPI fixed event when the enable bit is set again
+		 */
+		# press the power button for 3 times;
+		# cat ff_pwr_btn
+		7
+		# echo disable > ff_pwr_btn
+		# press the power button for 3 times;
+		# echo clear > ff_pwr_btn	/* clear the status bit */
+		# echo disable > ff_pwr_btn
+		# cat ff_pwr_btn
+		7
+

Documentation/ABI/testing/sysfs-firmware-memmap

@@ -0,0 +1,71 @@
+What:		/sys/firmware/memmap/
+Date:		June 2008
+Contact:	Bernhard Walle <bwalle@suse.de>
+Description:
+		On all platforms, the firmware provides a memory map which the
+		kernel reads. The resources from that memory map are registered
+		in the kernel resource tree and exposed to userspace via
+		/proc/iomem (together with other resources).
+
+		However, on most architectures that firmware-provided memory
+		map is modified afterwards by the kernel itself, either because
+		the kernel merges that memory map with other information or
+		just because the user overwrites that memory map via command
+		line.
+
+		kexec needs the raw firmware-provided memory map to setup the
+		parameter segment of the kernel that should be booted with
+		kexec. Also, the raw memory map is useful for debugging. For
+		that reason, /sys/firmware/memmap is an interface that provides
+		the raw memory map to userspace.
+
+		The structure is as follows: Under /sys/firmware/memmap there
+		are subdirectories with the number of the entry as their name:
+
+			/sys/firmware/memmap/0
+			/sys/firmware/memmap/1
+			/sys/firmware/memmap/2
+			/sys/firmware/memmap/3
+			...
+
+		The maximum depends on the number of memory map entries provided
+		by the firmware. The order is just the order that the firmware
+		provides.
+
+		Each directory contains three files:
+
+		start	: The start address (as hexadecimal number with the
+			  '0x' prefix).
+		end	: The end address, inclusive (regardless whether the
+			  firmware provides inclusive or exclusive ranges).
+		type	: Type of the entry as string. See below for a list of
+			  valid types.
+
+		So, for example:
+
+			/sys/firmware/memmap/0/start
+			/sys/firmware/memmap/0/end
+			/sys/firmware/memmap/0/type
+			/sys/firmware/memmap/1/start
+			...
+
+		Currently following types exist:
+
+		  - System RAM
+		  - ACPI Tables
+		  - ACPI Non-volatile Storage
+		  - reserved
+
+		Following shell snippet can be used to display that memory
+		map in a human-readable format:
+
+		-------------------- 8< ----------------------------------------
+		  #!/bin/bash
+		  cd /sys/firmware/memmap
+		  for dir in * ; do
+		      start=$(cat $dir/start)
+		      end=$(cat $dir/end)
+		      type=$(cat $dir/type)
+		      printf "%016x-%016x (%s)\n" $start $[ $end +1] "$type"
+		  done
+		-------------------- >8 ----------------------------------------

Documentation/DocBook/kernel-locking.tmpl

@@ -703,6 +703,31 @@
 </sect1>
 </chapter>
 
+<chapter id="trylock-functions">
+ <title>The trylock Functions</title>
+  <para>
+   There are functions that try to acquire a lock only once and immediately
+   return a value telling about success or failure to acquire the lock.
+   They can be used if you need no access to the data protected with the lock
+   when some other thread is holding the lock. You should acquire the lock
+   later if you then need access to the data protected with the lock.
+  </para>
+
+  <para>
+    <function>spin_trylock()</function> does not spin but returns non-zero if
+    it acquires the spinlock on the first try or 0 if not. This function can
+    be used in all contexts like <function>spin_lock</function>: you must have
+    disabled the contexts that might interrupt you and acquire the spin lock.
+  </para>
+
+  <para>
+    <function>mutex_trylock()</function> does not suspend your task
+    but returns non-zero if it could lock the mutex on the first try
+    or 0 if not. This function cannot be safely used in hardware or software
+    interrupt contexts despite not sleeping.
+  </para>
+</chapter>
+
   <chapter id="Examples">
    <title>Common Examples</title>
     <para>

Documentation/DocBook/kgdb.tmpl

@@ -84,10 +84,9 @@
     runs an instance of gdb against the vmlinux file which contains
     the symbols (not boot image such as bzImage, zImage, uImage...).
     In gdb the developer specifies the connection parameters and
-    connects to kgdb.  Depending on which kgdb I/O modules exist in
-    the kernel for a given architecture, it may be possible to debug
-    the test machine's kernel with the development machine using a
-    rs232 or ethernet connection.
+    connects to kgdb.  The type of connection a developer makes with
+    gdb depends on the availability of kgdb I/O modules compiled as
+    builtin's or kernel modules in the test machine's kernel.
     </para>
   </chapter>
   <chapter id="CompilingAKernel">
@@ -223,7 +222,7 @@
   </para>
   <para>
   IMPORTANT NOTE: Using this option with kgdb over the console
-  (kgdboc) or kgdb over ethernet (kgdboe) is not supported.
+  (kgdboc) is not supported.
   </para>
   </sect1>
   </chapter>
@@ -249,18 +248,11 @@
     (gdb) target remote /dev/ttyS0
     </programlisting>
     <para>
-    Example (kgdb to a terminal server):
+    Example (kgdb to a terminal server on tcp port 2012):
     </para>
     <programlisting>
     % gdb ./vmlinux
-    (gdb) target remote udp:192.168.2.2:6443
-    </programlisting>
-    <para>
-    Example (kgdb over ethernet):
-    </para>
-    <programlisting>
-    % gdb ./vmlinux
-    (gdb) target remote udp:192.168.2.2:6443
+    (gdb) target remote 192.168.2.2:2012
     </programlisting>
     <para>
     Once connected, you can debug a kernel the way you would debug an

Documentation/HOWTO

@@ -377,7 +377,7 @@ Bug Reporting
 bugzilla.kernel.org is where the Linux kernel developers track kernel
 bugs.  Users are encouraged to report all bugs that they find in this
 tool.  For details on how to use the kernel bugzilla, please see:
-	http://test.kernel.org/bugzilla/faq.html
+	http://bugzilla.kernel.org/page.cgi?id=faq.html
 
 The file REPORTING-BUGS in the main kernel source directory has a good
 template for how to report a possible kernel bug, and details what kind

Documentation/IRQ-affinity.txt

@@ -1,17 +1,26 @@
+ChangeLog:
+	Started by Ingo Molnar <mingo@redhat.com>
+	Update by Max Krasnyansky <maxk@qualcomm.com>
 
-SMP IRQ affinity, started by Ingo Molnar <mingo@redhat.com>
-
+SMP IRQ affinity
 
 /proc/irq/IRQ#/smp_affinity specifies which target CPUs are permitted
 for a given IRQ source. It's a bitmask of allowed CPUs. It's not allowed
 to turn off all CPUs, and if an IRQ controller does not support IRQ
 affinity then the value will not change from the default 0xffffffff.
 
+/proc/irq/default_smp_affinity specifies default affinity mask that applies
+to all non-active IRQs. Once IRQ is allocated/activated its affinity bitmask
+will be set to the default mask. It can then be changed as described above.
+Default mask is 0xffffffff.
+
 Here is an example of restricting IRQ44 (eth1) to CPU0-3 then restricting
-the IRQ to CPU4-7 (this is an 8-CPU SMP box):
+it to CPU4-7 (this is an 8-CPU SMP box):
 
+[root@moon 44]# cd /proc/irq/44
 [root@moon 44]# cat smp_affinity
 ffffffff
+
 [root@moon 44]# echo 0f > smp_affinity
 [root@moon 44]# cat smp_affinity
 0000000f
@@ -21,17 +30,27 @@ PING hell (195.4.7.3): 56 data bytes
 --- hell ping statistics ---
 6029 packets transmitted, 6027 packets received, 0% packet loss
 round-trip min/avg/max = 0.1/0.1/0.4 ms
-[root@moon 44]# cat /proc/interrupts | grep 44:
- 44:          0       1785       1785       1783       1783          1
-1          0   IO-APIC-level  eth1
+[root@moon 44]# cat /proc/interrupts | grep 'CPU\|44:'
+           CPU0       CPU1       CPU2       CPU3      CPU4       CPU5        CPU6       CPU7
+ 44:       1068       1785       1785       1783         0          0           0         0    IO-APIC-level  eth1
+
+As can be seen from the line above IRQ44 was delivered only to the first four
+processors (0-3).
+Now lets restrict that IRQ to CPU(4-7).
+
 [root@moon 44]# echo f0 > smp_affinity
+[root@moon 44]# cat smp_affinity
+000000f0
 [root@moon 44]# ping -f h
 PING hell (195.4.7.3): 56 data bytes
 ..
 --- hell ping statistics ---
 2779 packets transmitted, 2777 packets received, 0% packet loss
 round-trip min/avg/max = 0.1/0.5/585.4 ms
-[root@moon 44]# cat /proc/interrupts | grep 44:
- 44:       1068       1785       1785       1784       1784       1069       1070       1069   IO-APIC-level  eth1
-[root@moon 44]#
+[root@moon 44]# cat /proc/interrupts |  'CPU\|44:'
+           CPU0       CPU1       CPU2       CPU3      CPU4       CPU5        CPU6       CPU7
+ 44:       1068       1785       1785       1783      1784       1069        1070       1069   IO-APIC-level  eth1
+
+This time around IRQ44 was delivered only to the last four processors.
+i.e counters for the CPU0-3 did not change.
 

Documentation/RCU/NMI-RCU.txt

@@ -93,6 +93,9 @@ Since NMI handlers disable preemption, synchronize_sched() is guaranteed
 not to return until all ongoing NMI handlers exit.  It is therefore safe
 to free up the handler's data as soon as synchronize_sched() returns.
 
+Important note: for this to work, the architecture in question must
+invoke irq_enter() and irq_exit() on NMI entry and exit, respectively.
+
 
 Answer to Quick Quiz
 

Documentation/RCU/RTFP.txt

@@ -52,6 +52,10 @@ of each iteration.  Unfortunately, chaotic relaxation requires highly
 structured data, such as the matrices used in scientific programs, and
 is thus inapplicable to most data structures in operating-system kernels.
 
+In 1992, Henry (now Alexia) Massalin completed a dissertation advising
+parallel programmers to defer processing when feasible to simplify
+synchronization.  RCU makes extremely heavy use of this advice.
+
 In 1993, Jacobson [Jacobson93] verbally described what is perhaps the
 simplest deferred-free technique: simply waiting a fixed amount of time
 before freeing blocks awaiting deferred free.  Jacobson did not describe
@@ -138,6 +142,13 @@ blocking in read-side critical sections appeared [PaulEMcKenney2006c],
 Robert Olsson described an RCU-protected trie-hash combination
 [RobertOlsson2006a].
 
+2007 saw the journal version of the award-winning RCU paper from 2006
+[ThomasEHart2007a], as well as a paper demonstrating use of Promela
+and Spin to mechanically verify an optimization to Oleg Nesterov's
+QRCU [PaulEMcKenney2007QRCUspin], a design document describing
+preemptible RCU [PaulEMcKenney2007PreemptibleRCU], and the three-part
+LWN "What is RCU?" series [PaulEMcKenney2007WhatIsRCUFundamentally,
+PaulEMcKenney2008WhatIsRCUUsage, and PaulEMcKenney2008WhatIsRCUAPI].
 
 Bibtex Entries
 
@@ -202,6 +213,20 @@ Bibtex Entries
 ,Year="1991"
 }
 
+@phdthesis{HMassalinPhD
+,author="H. Massalin"
+,title="Synthesis: An Efficient Implementation of Fundamental Operating
+System Services"
+,school="Columbia University"
+,address="New York, NY"
+,year="1992"
+,annotation="
+	Mondo optimizing compiler.
+	Wait-free stuff.
+	Good advice: defer work to avoid synchronization.
+"
+}
+
 @unpublished{Jacobson93
 ,author="Van Jacobson"
 ,title="Avoid Read-Side Locking Via Delayed Free"
@@ -635,3 +660,86 @@ Revised:
 "
 }
 
+@unpublished{PaulEMcKenney2007PreemptibleRCU
+,Author="Paul E. McKenney"
+,Title="The design of preemptible read-copy-update"
+,month="October"
+,day="8"
+,year="2007"
+,note="Available:
+\url{http://lwn.net/Articles/253651/}
+[Viewed October 25, 2007]"
+,annotation="
+	LWN article describing the design of preemptible RCU.
+"
+}
+
+########################################################################
+#
+#	"What is RCU?" LWN series.
+#
+
+@unpublished{PaulEMcKenney2007WhatIsRCUFundamentally
+,Author="Paul E. McKenney and Jonathan Walpole"
+,Title="What is {RCU}, Fundamentally?"
+,month="December"
+,day="17"
+,year="2007"
+,note="Available:
+\url{http://lwn.net/Articles/262464/}
+[Viewed December 27, 2007]"
+,annotation="
+	Lays out the three basic components of RCU: (1) publish-subscribe,
+	(2) wait for pre-existing readers to complete, and (2) maintain
+	multiple versions.
+"
+}
+
+@unpublished{PaulEMcKenney2008WhatIsRCUUsage
+,Author="Paul E. McKenney"
+,Title="What is {RCU}? Part 2: Usage"
+,month="January"
+,day="4"
+,year="2008"
+,note="Available:
+\url{http://lwn.net/Articles/263130/}
+[Viewed January 4, 2008]"
+,annotation="
+	Lays out six uses of RCU:
+	1. RCU is a Reader-Writer Lock Replacement
+	2. RCU is a Restricted Reference-Counting Mechanism
+	3. RCU is a Bulk Reference-Counting Mechanism
+	4. RCU is a Poor Man's Garbage Collector
+	5. RCU is a Way of Providing Existence Guarantees
+	6. RCU is a Way of Waiting for Things to Finish 
+"
+}
+
+@unpublished{PaulEMcKenney2008WhatIsRCUAPI
+,Author="Paul E. McKenney"
+,Title="{RCU} part 3: the {RCU} {API}"
+,month="January"
+,day="17"
+,year="2008"
+,note="Available:
+\url{http://lwn.net/Articles/264090/}
+[Viewed January 10, 2008]"
+,annotation="
+	Gives an overview of the Linux-kernel RCU API and a brief annotated RCU
+	bibliography.
+"
+}
+
+@article{DinakarGuniguntala2008IBMSysJ
+,author="D. Guniguntala and P. E. McKenney and J. Triplett and J. Walpole"
+,title="The read-copy-update mechanism for supporting real-time applications on shared-memory multiprocessor systems with {Linux}"
+,Year="2008"
+,Month="April"
+,journal="IBM Systems Journal"
+,volume="47"
+,number="2"
+,pages="@@-@@"
+,annotation="
+	RCU, realtime RCU, sleepable RCU, performance.
+"
+}

Documentation/RCU/checklist.txt

@@ -13,10 +13,13 @@ over a rather long period of time, but improvements are always welcome!
 	detailed performance measurements show that RCU is nonetheless
 	the right tool for the job.
 
-	The other exception would be where performance is not an issue,
-	and RCU provides a simpler implementation.  An example of this
-	situation is the dynamic NMI code in the Linux 2.6 kernel,
-	at least on architectures where NMIs are rare.
+	Another exception is where performance is not an issue, and RCU
+	provides a simpler implementation.  An example of this situation
+	is the dynamic NMI code in the Linux 2.6 kernel, at least on
+	architectures where NMIs are rare.
+
+	Yet another exception is where the low real-time latency of RCU's
+	read-side primitives is critically important.
 
 1.	Does the update code have proper mutual exclusion?
 
@@ -39,9 +42,10 @@ over a rather long period of time, but improvements are always welcome!
 
 2.	Do the RCU read-side critical sections make proper use of
 	rcu_read_lock() and friends?  These primitives are needed
-	to suppress preemption (or bottom halves, in the case of
-	rcu_read_lock_bh()) in the read-side critical sections,
-	and are also an excellent aid to readability.
+	to prevent grace periods from ending prematurely, which
+	could result in data being unceremoniously freed out from
+	under your read-side code, which can greatly increase the
+	actuarial risk of your kernel.
 
 	As a rough rule of thumb, any dereference of an RCU-protected
 	pointer must be covered by rcu_read_lock() or rcu_read_lock_bh()
@@ -54,15 +58,30 @@ over a rather long period of time, but improvements are always welcome!
 	be running while updates are in progress.  There are a number
 	of ways to handle this concurrency, depending on the situation:
 
-	a.	Make updates appear atomic to readers.  For example,
+	a.	Use the RCU variants of the list and hlist update
+		primitives to add, remove, and replace elements on an
+		RCU-protected list.  Alternatively, use the RCU-protected
+		trees that have been added to the Linux kernel.
+
+		This is almost always the best approach.
+
+	b.	Proceed as in (a) above, but also maintain per-element
+		locks (that are acquired by both readers and writers)
+		that guard per-element state.  Of course, fields that
+		the readers refrain from accessing can be guarded by the
+		update-side lock.
+
+		This works quite well, also.
+
+	c.	Make updates appear atomic to readers.  For example,
 		pointer updates to properly aligned fields will appear
 		atomic, as will individual atomic primitives.  Operations
 		performed under a lock and sequences of multiple atomic
 		primitives will -not- appear to be atomic.
 
-		This is almost always the best approach.
+		This can work, but is starting to get a bit tricky.
 
-	b.	Carefully order the updates and the reads so that
+	d.	Carefully order the updates and the reads so that
 		readers see valid data at all phases of the update.
 		This is often more difficult than it sounds, especially
 		given modern CPUs' tendency to reorder memory references.
@@ -123,18 +142,22 @@ over a rather long period of time, but improvements are always welcome!
 		when publicizing a pointer to a structure that can
 		be traversed by an RCU read-side critical section.
 
-5.	If call_rcu(), or a related primitive such as call_rcu_bh(),
-	is used, the callback function must be written to be called
-	from softirq context.  In particular, it cannot block.
+5.	If call_rcu(), or a related primitive such as call_rcu_bh() or
+	call_rcu_sched(), is used, the callback function must be
+	written to be called from softirq context.  In particular,
+	it cannot block.
 
 6.	Since synchronize_rcu() can block, it cannot be called from
-	any sort of irq context.
+	any sort of irq context.  Ditto for synchronize_sched() and
+	synchronize_srcu().
 
 7.	If the updater uses call_rcu(), then the corresponding readers
 	must use rcu_read_lock() and rcu_read_unlock().  If the updater
 	uses call_rcu_bh(), then the corresponding readers must use
-	rcu_read_lock_bh() and rcu_read_unlock_bh().  Mixing things up
-	will result in confusion and broken kernels.
+	rcu_read_lock_bh() and rcu_read_unlock_bh().  If the updater
+	uses call_rcu_sched(), then the corresponding readers must
+	disable preemption.  Mixing things up will result in confusion
+	and broken kernels.
 
 	One exception to this rule: rcu_read_lock() and rcu_read_unlock()
 	may be substituted for rcu_read_lock_bh() and rcu_read_unlock_bh()
@@ -143,9 +166,9 @@ over a rather long period of time, but improvements are always welcome!
 	such cases is a must, of course!  And the jury is still out on
 	whether the increased speed is worth it.
 
-8.	Although synchronize_rcu() is a bit slower than is call_rcu(),
-	it usually results in simpler code.  So, unless update
-	performance is critically important or the updaters cannot block,
+8.	Although synchronize_rcu() is slower than is call_rcu(), it
+	usually results in simpler code.  So, unless update performance
+	is critically important or the updaters cannot block,
 	synchronize_rcu() should be used in preference to call_rcu().
 
 	An especially important property of the synchronize_rcu()
@@ -187,23 +210,23 @@ over a rather long period of time, but improvements are always welcome!
 		number of updates per grace period.
 
 9.	All RCU list-traversal primitives, which include
-	list_for_each_rcu(), list_for_each_entry_rcu(),
+	rcu_dereference(), list_for_each_rcu(), list_for_each_entry_rcu(),
 	list_for_each_continue_rcu(), and list_for_each_safe_rcu(),
-	must be within an RCU read-side critical section.  RCU
+	must be either within an RCU read-side critical section or
+	must be protected by appropriate update-side locks.  RCU
 	read-side critical sections are delimited by rcu_read_lock()
 	and rcu_read_unlock(), or by similar primitives such as
 	rcu_read_lock_bh() and rcu_read_unlock_bh().
 
-	Use of the _rcu() list-traversal primitives outside of an
-	RCU read-side critical section causes no harm other than
-	a slight performance degradation on Alpha CPUs.  It can
-	also be quite helpful in reducing code bloat when common
-	code is shared between readers and updaters.
+	The reason that it is permissible to use RCU list-traversal
+	primitives when the update-side lock is held is that doing so
+	can be quite helpful in reducing code bloat when common code is
+	shared between readers and updaters.
 
 10.	Conversely, if you are in an RCU read-side critical section,
-	you -must- use the "_rcu()" variants of the list macros.
-	Failing to do so will break Alpha and confuse people reading
-	your code.
+	and you don't hold the appropriate update-side lock, you -must-
+	use the "_rcu()" variants of the list macros.  Failing to do so
+	will break Alpha and confuse people reading your code.
 
 11.	Note that synchronize_rcu() -only- guarantees to wait until
 	all currently executing rcu_read_lock()-protected RCU read-side
@@ -230,6 +253,14 @@ over a rather long period of time, but improvements are always welcome!
 	must use whatever locking or other synchronization is required
 	to safely access and/or modify that data structure.
 
+	RCU callbacks are -usually- executed on the same CPU that executed
+	the corresponding call_rcu(), call_rcu_bh(), or call_rcu_sched(),
+	but are by -no- means guaranteed to be.  For example, if a given
+	CPU goes offline while having an RCU callback pending, then that
+	RCU callback will execute on some surviving CPU.  (If this was
+	not the case, a self-spawning RCU callback would prevent the
+	victim CPU from ever going offline.)
+
 14.	SRCU (srcu_read_lock(), srcu_read_unlock(), and synchronize_srcu())
 	may only be invoked from process context.  Unlike other forms of
 	RCU, it -is- permissible to block in an SRCU read-side critical

Documentation/RCU/torture.txt

@@ -10,23 +10,30 @@ status messages via printk(), which can be examined via the dmesg
 command (perhaps grepping for "torture").  The test is started
 when the module is loaded, and stops when the module is unloaded.
 
-However, actually setting this config option to "y" results in the system
-running the test immediately upon boot, and ending only when the system
-is taken down.  Normally, one will instead want to build the system
-with CONFIG_RCU_TORTURE_TEST=m and to use modprobe and rmmod to control
-the test, perhaps using a script similar to the one shown at the end of
-this document.  Note that you will need CONFIG_MODULE_UNLOAD in order
-to be able to end the test.
+CONFIG_RCU_TORTURE_TEST_RUNNABLE
+
+It is also possible to specify CONFIG_RCU_TORTURE_TEST=y, which will
+result in the tests being loaded into the base kernel.  In this case,
+the CONFIG_RCU_TORTURE_TEST_RUNNABLE config option is used to specify
+whether the RCU torture tests are to be started immediately during
+boot or whether the /proc/sys/kernel/rcutorture_runnable file is used
+to enable them.  This /proc file can be used to repeatedly pause and
+restart the tests, regardless of the initial state specified by the
+CONFIG_RCU_TORTURE_TEST_RUNNABLE config option.
+
+You will normally -not- want to start the RCU torture tests during boot
+(and thus the default is CONFIG_RCU_TORTURE_TEST_RUNNABLE=n), but doing
+this can sometimes be useful in finding boot-time bugs.
 
 
 MODULE PARAMETERS
 
 This module has the following parameters:
 
-nreaders	This is the number of RCU reading threads supported.
-		The default is twice the number of CPUs.  Why twice?
-		To properly exercise RCU implementations with preemptible
-		read-side critical sections.
+irqreaders	Says to invoke RCU readers from irq level.  This is currently
+		done via timers.  Defaults to "1" for variants of RCU that
+		permit this.  (Or, more accurately, variants of RCU that do
+		-not- permit this know to ignore this variable.)
 
 nfakewriters	This is the number of RCU fake writer threads to run.  Fake
 		writer threads repeatedly use the synchronous "wait for
@@ -37,6 +44,16 @@ nfakewriters	This is the number of RCU fake writer threads to run.  Fake
 		to trigger special cases caused by multiple writers, such as
 		the synchronize_srcu() early return optimization.
 
+nreaders	This is the number of RCU reading threads supported.
+		The default is twice the number of CPUs.  Why twice?
+		To properly exercise RCU implementations with preemptible
+		read-side critical sections.
+
+shuffle_interval
+		The number of seconds to keep the test threads affinitied
+		to a particular subset of the CPUs, defaults to 3 seconds.
+		Used in conjunction with test_no_idle_hz.
+
 stat_interval	The number of seconds between output of torture
 		statistics (via printk()).  Regardless of the interval,
 		statistics are printed when the module is unloaded.
@@ -44,10 +61,11 @@ stat_interval	The number of seconds between output of torture
 		be printed -only- when the module is unloaded, and this
 		is the default.
 
-shuffle_interval
-		The number of seconds to keep the test threads affinitied
-		to a particular subset of the CPUs, defaults to 5 seconds.
-		Used in conjunction with test_no_idle_hz.
+stutter		The length of time to run the test before pausing for this
+		same period of time.  Defaults to "stutter=5", so as
+		to run and pause for (roughly) five-second intervals.
+		Specifying "stutter=0" causes the test to run continuously
+		without pausing, which is the old default behavior.
 
 test_no_idle_hz	Whether or not to test the ability of RCU to operate in
 		a kernel that disables the scheduling-clock interrupt to

Documentation/RCU/whatisRCU.txt

@@ -1,3 +1,11 @@
+Please note that the "What is RCU?" LWN series is an excellent place
+to start learning about RCU:
+
+1.	What is RCU, Fundamentally?  http://lwn.net/Articles/262464/
+2.	What is RCU? Part 2: Usage   http://lwn.net/Articles/263130/
+3.	RCU part 3: the RCU API      http://lwn.net/Articles/264090/
+
+
 What is RCU?
 
 RCU is a synchronization mechanism that was added to the Linux kernel
@@ -772,26 +780,18 @@ Linux-kernel source code, but it helps to have a full list of the
 APIs, since there does not appear to be a way to categorize them
 in docbook.  Here is the list, by category.
 
-Markers for RCU read-side critical sections:
-
-	rcu_read_lock
-	rcu_read_unlock
-	rcu_read_lock_bh
-	rcu_read_unlock_bh
-	srcu_read_lock
-	srcu_read_unlock
-
 RCU pointer/list traversal:
 
 	rcu_dereference
+	list_for_each_entry_rcu
+	hlist_for_each_entry_rcu
+
 	list_for_each_rcu		(to be deprecated in favor of
 					 list_for_each_entry_rcu)
-	list_for_each_entry_rcu
 	list_for_each_continue_rcu	(to be deprecated in favor of new
 					 list_for_each_entry_continue_rcu)
-	hlist_for_each_entry_rcu
 
-RCU pointer update:
+RCU pointer/list update:
 
 	rcu_assign_pointer
 	list_add_rcu
@@ -799,16 +799,36 @@ RCU pointer update:
 	list_del_rcu
 	list_replace_rcu
 	hlist_del_rcu
+	hlist_add_after_rcu
+	hlist_add_before_rcu
 	hlist_add_head_rcu
+	hlist_replace_rcu
+	list_splice_init_rcu()
 
-RCU grace period:
+RCU:	Critical sections	Grace period		Barrier
+
+	rcu_read_lock		synchronize_net		rcu_barrier
+	rcu_read_unlock		synchronize_rcu
+				call_rcu
+
+
+bh:	Critical sections	Grace period		Barrier
+
+	rcu_read_lock_bh	call_rcu_bh		rcu_barrier_bh
+	rcu_read_unlock_bh
+
+
+sched:	Critical sections	Grace period		Barrier
+
+	[preempt_disable]	synchronize_sched	rcu_barrier_sched
+	[and friends]		call_rcu_sched
+
+
+SRCU:	Critical sections	Grace period		Barrier
+
+	srcu_read_lock		synchronize_srcu	N/A
+	srcu_read_unlock
 
-	synchronize_net
-	synchronize_sched
-	synchronize_rcu
-	synchronize_srcu
-	call_rcu
-	call_rcu_bh
 
 See the comment headers in the source code (or the docbook generated
 from them) for more information.

Documentation/SubmittingPatches

@@ -327,6 +327,52 @@ Some people also put extra tags at the end.  They'll just be ignored for
 now, but you can do this to mark internal company procedures or just
 point out some special detail about the sign-off. 
 
+If you are a subsystem or branch maintainer, sometimes you need to slightly
+modify patches you receive in order to merge them, because the code is not
+exactly the same in your tree and the submitters'. If you stick strictly to
+rule (c), you should ask the submitter to rediff, but this is a totally
+counter-productive waste of time and energy. Rule (b) allows you to adjust
+the code, but then it is very impolite to change one submitter's code and
+make him endorse your bugs. To solve this problem, it is recommended that
+you add a line between the last Signed-off-by header and yours, indicating
+the nature of your changes. While there is nothing mandatory about this, it
+seems like prepending the description with your mail and/or name, all
+enclosed in square brackets, is noticeable enough to make it obvious that
+you are responsible for last-minute changes. Example :
+
+	Signed-off-by: Random J Developer <random@developer.example.org>
+	[lucky@maintainer.example.org: struct foo moved from foo.c to foo.h]
+	Signed-off-by: Lucky K Maintainer <lucky@maintainer.example.org>
+
+This practise is particularly helpful if you maintain a stable branch and
+want at the same time to credit the author, track changes, merge the fix,
+and protect the submitter from complaints. Note that under no circumstances
+can you change the author's identity (the From header), as it is the one
+which appears in the changelog.
+
+Special note to back-porters: It seems to be a common and useful practise
+to insert an indication of the origin of a patch at the top of the commit
+message (just after the subject line) to facilitate tracking. For instance,
+here's what we see in 2.6-stable :
+
+    Date:   Tue May 13 19:10:30 2008 +0000
+
+        SCSI: libiscsi regression in 2.6.25: fix nop timer handling
+
+        commit 4cf1043593db6a337f10e006c23c69e5fc93e722 upstream
+
+And here's what appears in 2.4 :
+
+    Date:   Tue May 13 22:12:27 2008 +0200
+
+        wireless, airo: waitbusy() won't delay
+
+        [backport of 2.6 commit b7acbdfbd1f277c1eb23f344f899cfa4cd0bf36a]
+
+Whatever the format, this information provides a valuable help to people
+tracking your trees, and to people trying to trouble-shoot bugs in your
+tree.
+
 
 13) When to use Acked-by: and Cc:
 

Documentation/accounting/taskstats-struct.txt

@@ -24,6 +24,8 @@ There are three different groups of fields in the struct taskstats:
 
 4) Per-task and per-thread context switch count statistics
 
+5) Time accounting for SMT machines
+
 Future extension should add fields to the end of the taskstats struct, and
 should not change the relative position of each field within the struct.
 
@@ -164,4 +166,8 @@ struct taskstats {
 	__u64	nvcsw;			/* Context voluntary switch counter */
 	__u64	nivcsw;			/* Context involuntary switch counter */
 
+5) Time accounting for SMT machines
+	__u64	ac_utimescaled;		/* utime scaled on frequency etc */
+	__u64	ac_stimescaled;		/* stime scaled on frequency etc */
+	__u64	cpu_scaled_run_real_total; /* scaled cpu_run_real_total */
 }

Documentation/auxdisplay/cfag12864b

@@ -3,7 +3,7 @@
 	===================================
 
 License:		GPLv2
-Author & Maintainer:	Miguel Ojeda Sandonis <maxextreme@gmail.com>
+Author & Maintainer:	Miguel Ojeda Sandonis
 Date:			2006-10-27
 
 
@@ -22,7 +22,7 @@ Date:			2006-10-27
 1. DRIVER INFORMATION
 ---------------------
 
-This driver support one cfag12864b display at time.
+This driver supports a cfag12864b LCD.
 
 
 ---------------------

Documentation/auxdisplay/cfag12864b-example.c

@@ -4,7 +4,7 @@
  * Description: cfag12864b LCD userspace example program
  *     License: GPLv2
  *
- *      Author: Copyright (C) Miguel Ojeda Sandonis <maxextreme@gmail.com>
+ *      Author: Copyright (C) Miguel Ojeda Sandonis
  *        Date: 2006-10-31
  *
  *  This program is free software; you can redistribute it and/or modify

Documentation/auxdisplay/ks0108

@@ -3,7 +3,7 @@
 	==========================================
 
 License:		GPLv2
-Author & Maintainer:	Miguel Ojeda Sandonis <maxextreme@gmail.com>
+Author & Maintainer:	Miguel Ojeda Sandonis
 Date:			2006-10-27
 
 
@@ -21,7 +21,7 @@ Date:			2006-10-27
 1. DRIVER INFORMATION
 ---------------------
 
-This driver support the ks0108 LCD controller.
+This driver supports the ks0108 LCD controller.
 
 
 ---------------------

Documentation/block/data-integrity.txt

@@ -0,0 +1,327 @@
+----------------------------------------------------------------------
+1. INTRODUCTION
+
+Modern filesystems feature checksumming of data and metadata to
+protect against data corruption.  However, the detection of the
+corruption is done at read time which could potentially be months
+after the data was written.  At that point the original data that the
+application tried to write is most likely lost.
+
+The solution is to ensure that the disk is actually storing what the
+application meant it to.  Recent additions to both the SCSI family
+protocols (SBC Data Integrity Field, SCC protection proposal) as well
+as SATA/T13 (External Path Protection) try to remedy this by adding
+support for appending integrity metadata to an I/O.  The integrity
+metadata (or protection information in SCSI terminology) includes a
+checksum for each sector as well as an incrementing counter that
+ensures the individual sectors are written in the right order.  And
+for some protection schemes also that the I/O is written to the right
+place on disk.
+
+Current storage controllers and devices implement various protective
+measures, for instance checksumming and scrubbing.  But these
+technologies are working in their own isolated domains or at best
+between adjacent nodes in the I/O path.  The interesting thing about
+DIF and the other integrity extensions is that the protection format
+is well defined and every node in the I/O path can verify the
+integrity of the I/O and reject it if corruption is detected.  This
+allows not only corruption prevention but also isolation of the point
+of failure.
+
+----------------------------------------------------------------------
+2. THE DATA INTEGRITY EXTENSIONS
+
+As written, the protocol extensions only protect the path between
+controller and storage device.  However, many controllers actually
+allow the operating system to interact with the integrity metadata
+(IMD).  We have been working with several FC/SAS HBA vendors to enable
+the protection information to be transferred to and from their
+controllers.
+
+The SCSI Data Integrity Field works by appending 8 bytes of protection
+information to each sector.  The data + integrity metadata is stored
+in 520 byte sectors on disk.  Data + IMD are interleaved when
+transferred between the controller and target.  The T13 proposal is
+similar.
+
+Because it is highly inconvenient for operating systems to deal with
+520 (and 4104) byte sectors, we approached several HBA vendors and
+encouraged them to allow separation of the data and integrity metadata
+scatter-gather lists.
+
+The controller will interleave the buffers on write and split them on
+read.  This means that the Linux can DMA the data buffers to and from
+host memory without changes to the page cache.
+
+Also, the 16-bit CRC checksum mandated by both the SCSI and SATA specs
+is somewhat heavy to compute in software.  Benchmarks found that
+calculating this checksum had a significant impact on system
+performance for a number of workloads.  Some controllers allow a
+lighter-weight checksum to be used when interfacing with the operating
+system.  Emulex, for instance, supports the TCP/IP checksum instead.
+The IP checksum received from the OS is converted to the 16-bit CRC
+when writing and vice versa.  This allows the integrity metadata to be
+generated by Linux or the application at very low cost (comparable to
+software RAID5).
+
+The IP checksum is weaker than the CRC in terms of detecting bit
+errors.  However, the strength is really in the separation of the data
+buffers and the integrity metadata.  These two distinct buffers much
+match up for an I/O to complete.
+
+The separation of the data and integrity metadata buffers as well as
+the choice in checksums is referred to as the Data Integrity
+Extensions.  As these extensions are outside the scope of the protocol
+bodies (T10, T13), Oracle and its partners are trying to standardize
+them within the Storage Networking Industry Association.
+
+----------------------------------------------------------------------
+3. KERNEL CHANGES
+
+The data integrity framework in Linux enables protection information
+to be pinned to I/Os and sent to/received from controllers that
+support it.
+
+The advantage to the integrity extensions in SCSI and SATA is that
+they enable us to protect the entire path from application to storage
+device.  However, at the same time this is also the biggest
+disadvantage. It means that the protection information must be in a
+format that can be understood by the disk.
+
+Generally Linux/POSIX applications are agnostic to the intricacies of
+the storage devices they are accessing.  The virtual filesystem switch
+and the block layer make things like hardware sector size and
+transport protocols completely transparent to the application.
+
+However, this level of detail is required when preparing the
+protection information to send to a disk.  Consequently, the very
+concept of an end-to-end protection scheme is a layering violation.
+It is completely unreasonable for an application to be aware whether
+it is accessing a SCSI or SATA disk.
+
+The data integrity support implemented in Linux attempts to hide this
+from the application.  As far as the application (and to some extent
+the kernel) is concerned, the integrity metadata is opaque information
+that's attached to the I/O.
+
+The current implementation allows the block layer to automatically
+generate the protection information for any I/O.  Eventually the
+intent is to move the integrity metadata calculation to userspace for
+user data.  Metadata and other I/O that originates within the kernel
+will still use the automatic generation interface.
+
+Some storage devices allow each hardware sector to be tagged with a
+16-bit value.  The owner of this tag space is the owner of the block
+device.  I.e. the filesystem in most cases.  The filesystem can use
+this extra space to tag sectors as they see fit.  Because the tag
+space is limited, the block interface allows tagging bigger chunks by
+way of interleaving.  This way, 8*16 bits of information can be
+attached to a typical 4KB filesystem block.
+
+This also means that applications such as fsck and mkfs will need
+access to manipulate the tags from user space.  A passthrough
+interface for this is being worked on.
+
+
+----------------------------------------------------------------------
+4. BLOCK LAYER IMPLEMENTATION DETAILS
+
+4.1 BIO
+
+The data integrity patches add a new field to struct bio when
+CONFIG_BLK_DEV_INTEGRITY is enabled.  bio->bi_integrity is a pointer
+to a struct bip which contains the bio integrity payload.  Essentially
+a bip is a trimmed down struct bio which holds a bio_vec containing
+the integrity metadata and the required housekeeping information (bvec
+pool, vector count, etc.)
+
+A kernel subsystem can enable data integrity protection on a bio by
+calling bio_integrity_alloc(bio).  This will allocate and attach the
+bip to the bio.
+
+Individual pages containing integrity metadata can subsequently be
+attached using bio_integrity_add_page().
+
+bio_free() will automatically free the bip.
+
+
+4.2 BLOCK DEVICE
+
+Because the format of the protection data is tied to the physical
+disk, each block device has been extended with a block integrity
+profile (struct blk_integrity).  This optional profile is registered
+with the block layer using blk_integrity_register().
+
+The profile contains callback functions for generating and verifying
+the protection data, as well as getting and setting application tags.
+The profile also contains a few constants to aid in completing,
+merging and splitting the integrity metadata.
+
+Layered block devices will need to pick a profile that's appropriate
+for all subdevices.  blk_integrity_compare() can help with that.  DM
+and MD linear, RAID0 and RAID1 are currently supported.  RAID4/5/6
+will require extra work due to the application tag.
+
+
+----------------------------------------------------------------------
+5.0 BLOCK LAYER INTEGRITY API
+
+5.1 NORMAL FILESYSTEM
+
+    The normal filesystem is unaware that the underlying block device
+    is capable of sending/receiving integrity metadata.  The IMD will
+    be automatically generated by the block layer at submit_bio() time
+    in case of a WRITE.  A READ request will cause the I/O integrity
+    to be verified upon completion.
+
+    IMD generation and verification can be toggled using the
+
+      /sys/block/<bdev>/integrity/write_generate
+
+    and
+
+      /sys/block/<bdev>/integrity/read_verify
+
+    flags.
+
+
+5.2 INTEGRITY-AWARE FILESYSTEM
+
+    A filesystem that is integrity-aware can prepare I/Os with IMD
+    attached.  It can also use the application tag space if this is
+    supported by the block device.
+
+
+    int bdev_integrity_enabled(block_device, int rw);
+
+      bdev_integrity_enabled() will return 1 if the block device
+      supports integrity metadata transfer for the data direction
+      specified in 'rw'.
+
+      bdev_integrity_enabled() honors the write_generate and
+      read_verify flags in sysfs and will respond accordingly.
+
+
+    int bio_integrity_prep(bio);
+
+      To generate IMD for WRITE and to set up buffers for READ, the
+      filesystem must call bio_integrity_prep(bio).
+
+      Prior to calling this function, the bio data direction and start
+      sector must be set, and the bio should have all data pages
+      added.  It is up to the caller to ensure that the bio does not
+      change while I/O is in progress.
+
+      bio_integrity_prep() should only be called if
+      bio_integrity_enabled() returned 1.
+
+
+    int bio_integrity_tag_size(bio);
+
+      If the filesystem wants to use the application tag space it will
+      first have to find out how much storage space is available.
+      Because tag space is generally limited (usually 2 bytes per
+      sector regardless of sector size), the integrity framework
+      supports interleaving the information between the sectors in an
+      I/O.
+
+      Filesystems can call bio_integrity_tag_size(bio) to find out how
+      many bytes of storage are available for that particular bio.
+
+      Another option is bdev_get_tag_size(block_device) which will
+      return the number of available bytes per hardware sector.
+
+
+    int bio_integrity_set_tag(bio, void *tag_buf, len);
+
+      After a successful return from bio_integrity_prep(),
+      bio_integrity_set_tag() can be used to attach an opaque tag
+      buffer to a bio.  Obviously this only makes sense if the I/O is
+      a WRITE.
+
+
+    int bio_integrity_get_tag(bio, void *tag_buf, len);
+
+      Similarly, at READ I/O completion time the filesystem can
+      retrieve the tag buffer using bio_integrity_get_tag().
+
+
+6.3 PASSING EXISTING INTEGRITY METADATA
+
+    Filesystems that either generate their own integrity metadata or
+    are capable of transferring IMD from user space can use the
+    following calls:
+
+
+    struct bip * bio_integrity_alloc(bio, gfp_mask, nr_pages);
+
+      Allocates the bio integrity payload and hangs it off of the bio.
+      nr_pages indicate how many pages of protection data need to be
+      stored in the integrity bio_vec list (similar to bio_alloc()).
+
+      The integrity payload will be freed at bio_free() time.
+
+
+    int bio_integrity_add_page(bio, page, len, offset);
+
+      Attaches a page containing integrity metadata to an existing
+      bio.  The bio must have an existing bip,
+      i.e. bio_integrity_alloc() must have been called.  For a WRITE,
+      the integrity metadata in the pages must be in a format
+      understood by the target device with the notable exception that
+      the sector numbers will be remapped as the request traverses the
+      I/O stack.  This implies that the pages added using this call
+      will be modified during I/O!  The first reference tag in the
+      integrity metadata must have a value of bip->bip_sector.
+
+      Pages can be added using bio_integrity_add_page() as long as
+      there is room in the bip bio_vec array (nr_pages).
+
+      Upon completion of a READ operation, the attached pages will
+      contain the integrity metadata received from the storage device.
+      It is up to the receiver to process them and verify data
+      integrity upon completion.
+
+
+6.4 REGISTERING A BLOCK DEVICE AS CAPABLE OF EXCHANGING INTEGRITY
+    METADATA
+
+    To enable integrity exchange on a block device the gendisk must be
+    registered as capable:
+
+    int blk_integrity_register(gendisk, blk_integrity);
+
+      The blk_integrity struct is a template and should contain the
+      following:
+
+        static struct blk_integrity my_profile = {
+            .name                   = "STANDARDSBODY-TYPE-VARIANT-CSUM",
+            .generate_fn            = my_generate_fn,
+       	    .verify_fn              = my_verify_fn,
+       	    .get_tag_fn             = my_get_tag_fn,
+       	    .set_tag_fn             = my_set_tag_fn,
+	    .tuple_size             = sizeof(struct my_tuple_size),
+	    .tag_size               = <tag bytes per hw sector>,
+        };
+
+      'name' is a text string which will be visible in sysfs.  This is
+      part of the userland API so chose it carefully and never change
+      it.  The format is standards body-type-variant.
+      E.g. T10-DIF-TYPE1-IP or T13-EPP-0-CRC.
+
+      'generate_fn' generates appropriate integrity metadata (for WRITE).
+
+      'verify_fn' verifies that the data buffer matches the integrity
+      metadata.
+
+      'tuple_size' must be set to match the size of the integrity
+      metadata per sector.  I.e. 8 for DIF and EPP.
+
+      'tag_size' must be set to identify how many bytes of tag space
+      are available per hardware sector.  For DIF this is either 2 or
+      0 depending on the value of the Control Mode Page ATO bit.
+
+      See 6.2 for a description of get_tag_fn and set_tag_fn.
+
+----------------------------------------------------------------------
+2007-12-24 Martin K. Petersen <martin.petersen@oracle.com>

Documentation/cciss.txt

@@ -21,6 +21,11 @@ This driver is known to work with the following cards:
 	* SA E200
 	* SA E200i
 	* SA E500
+	* SA P212
+	* SA P410
+	* SA P410i
+	* SA P411
+	* SA P812
 
 Detecting drive failures:
 -------------------------

Documentation/cgroups.txt

@@ -390,6 +390,10 @@ If you have several tasks to attach, you have to do it one after another:
 	...
 # /bin/echo PIDn > tasks
 
+You can attach the current shell task by echoing 0:
+
+# echo 0 > tasks
+
 3. Kernel API
 =============
 

Documentation/controllers/devices.txt

@@ -13,7 +13,7 @@ either an integer or * for all.  Access is a composition of r
 The root device cgroup starts with rwm to 'all'.  A child device
 cgroup gets a copy of the parent.  Administrators can then remove
 devices from the whitelist or add new entries.  A child cgroup can
-never receive a device access which is denied its parent.  However
+never receive a device access which is denied by its parent.  However
 when a device access is removed from a parent it will not also be
 removed from the child(ren).
 
@@ -29,7 +29,11 @@ allows cgroup 1 to read and mknod the device usually known as
 
 	echo a > /cgroups/1/devices.deny
 
-will remove the default 'a *:* mrw' entry.
+will remove the default 'a *:* rwm' entry. Doing
+
+	echo a > /cgroups/1/devices.allow
+
+will add the 'a *:* rwm' entry to the whitelist.
 
 3. Security
 

Documentation/cpu-freq/governors.txt

@@ -129,14 +129,6 @@ to its default value of '80' it means that between the checking
 intervals the CPU needs to be on average more than 80% in use to then
 decide that the CPU frequency needs to be increased.  
 
-sampling_down_factor: this parameter controls the rate that the CPU
-makes a decision on when to decrease the frequency.  When set to its
-default value of '5' it means that at 1/5 the sampling_rate the kernel
-makes a decision to lower the frequency.  Five "lower rate" decisions
-have to be made in a row before the CPU frequency is actually lower.
-If set to '1' then the frequency decreases as quickly as it increases,
-if set to '2' it decreases at half the rate of the increase.
-
 ignore_nice_load: this parameter takes a value of '0' or '1'. When
 set to '0' (its default), all processes are counted towards the
 'cpu utilisation' value.  When set to '1', the processes that are

Documentation/cpusets.txt

@@ -154,13 +154,15 @@ browsing and modifying the cpusets presently known to the kernel.  No
 new system calls are added for cpusets - all support for querying and
 modifying cpusets is via this cpuset file system.
 
-The /proc/<pid>/status file for each task has two added lines,
+The /proc/<pid>/status file for each task has four added lines,
 displaying the tasks cpus_allowed (on which CPUs it may be scheduled)
 and mems_allowed (on which Memory Nodes it may obtain memory),
-in the format seen in the following example:
+in the two formats seen in the following example:
 
   Cpus_allowed:   ffffffff,ffffffff,ffffffff,ffffffff
+  Cpus_allowed_list:      0-127
   Mems_allowed:   ffffffff,ffffffff
+  Mems_allowed_list:      0-63
 
 Each cpuset is represented by a directory in the cgroup file system
 containing (on top of the standard cgroup files) the following
@@ -199,7 +201,7 @@ using the sched_setaffinity, mbind and set_mempolicy system calls.
 The following rules apply to each cpuset:
 
  - Its CPUs and Memory Nodes must be a subset of its parents.
- - It can only be marked exclusive if its parent is.
+ - It can't be marked exclusive unless its parent is.
  - If its cpu or memory is exclusive, they may not overlap any sibling.
 
 These rules, and the natural hierarchy of cpusets, enable efficient
@@ -345,7 +347,7 @@ is modified to perform an inline check for this PF_SPREAD_PAGE task
 flag, and if set, a call to a new routine cpuset_mem_spread_node()
 returns the node to prefer for the allocation.
 
-Similarly, setting 'memory_spread_cache' turns on the flag
+Similarly, setting 'memory_spread_slab' turns on the flag
 PF_SPREAD_SLAB, and appropriately marked slab caches will allocate
 pages from the node returned by cpuset_mem_spread_node().
 
@@ -542,7 +544,10 @@ otherwise initial value -1 that indicates the cpuset has no request.
    2  : search cores in a package.
    3  : search cpus in a node [= system wide on non-NUMA system]
  ( 4  : search nodes in a chunk of node [on NUMA system] )
- ( 5~ : search system wide [on NUMA system])
+ ( 5  : search system wide [on NUMA system] )
+
+The system default is architecture dependent.  The system default
+can be changed using the relax_domain_level= boot parameter.
 
 This file is per-cpuset and affect the sched domain where the cpuset
 belongs to.  Therefore if the flag 'sched_load_balance' of a cpuset
@@ -709,7 +714,10 @@ Now you want to do something with this cpuset.
 
 In this directory you can find several files:
 # ls
-cpus  cpu_exclusive  mems  mem_exclusive mem_hardwall  tasks
+cpu_exclusive  memory_migrate      mems                      tasks
+cpus           memory_pressure     notify_on_release
+mem_exclusive  memory_spread_page  sched_load_balance
+mem_hardwall   memory_spread_slab  sched_relax_domain_level
 
 Reading them will give you information about the state of this cpuset:
 the CPUs and Memory Nodes it can use, the processes that are using

Documentation/cputopology.txt

@@ -14,9 +14,8 @@ represent the thread siblings to cpu X in the same physical package;
 To implement it in an architecture-neutral way, a new source file,
 drivers/base/topology.c, is to export the 4 attributes.
 
-If one architecture wants to support this feature, it just needs to
-implement 4 defines, typically in file include/asm-XXX/topology.h.
-The 4 defines are:
+For an architecture to support this feature, it must define some of
+these macros in include/asm-XXX/topology.h:
 #define topology_physical_package_id(cpu)
 #define topology_core_id(cpu)
 #define topology_thread_siblings(cpu)
@@ -25,17 +24,10 @@ The 4 defines are:
 The type of **_id is int.
 The type of siblings is cpumask_t.
 
-To be consistent on all architectures, the 4 attributes should have
-default values if their values are unavailable. Below is the rule.
-1) physical_package_id: If cpu has no physical package id, -1 is the
-default value.
-2) core_id: If cpu doesn't support multi-core, its core id is 0.
-3) thread_siblings: Just include itself, if the cpu doesn't support
-HT/multi-thread.
-4) core_siblings: Just include itself, if the cpu doesn't support
-multi-core and HT/Multi-thread.
-
-So be careful when declaring the 4 defines in include/asm-XXX/topology.h.
-
-If an attribute isn't defined on an architecture, it won't be exported.
-
+To be consistent on all architectures, include/linux/topology.h
+provides default definitions for any of the above macros that are
+not defined by include/asm-XXX/topology.h:
+1) physical_package_id: -1
+2) core_id: 0
+3) thread_siblings: just the given CPU
+4) core_siblings: just the given CPU

Documentation/feature-removal-schedule.txt

@@ -222,13 +222,6 @@ Who:	Thomas Gleixner <tglx@linutronix.de>
 
 ---------------------------
 
-What:	i2c-i810, i2c-prosavage and i2c-savage4
-When:	May 2008
-Why:	These drivers are superseded by i810fb, intelfb and savagefb.
-Who:	Jean Delvare <khali@linux-fr.org>
-
----------------------------
-
 What (Why):
 	- include/linux/netfilter_ipv4/ipt_TOS.h ipt_tos.h header files
 	  (superseded by xt_TOS/xt_tos target & match)
@@ -312,3 +305,34 @@ When:	2.6.26
 Why:	Implementation became generic; users should now include
 	linux/semaphore.h instead.
 Who:	Matthew Wilcox <willy@linux.intel.com>
+
+---------------------------
+
+What:	SCTP_GET_PEER_ADDRS_NUM_OLD, SCTP_GET_PEER_ADDRS_OLD,
+	SCTP_GET_LOCAL_ADDRS_NUM_OLD, SCTP_GET_LOCAL_ADDRS_OLD
+When: 	June 2009
+Why:    A newer version of the options have been introduced in 2005 that
+	removes the limitions of the old API.  The sctp library has been
+        converted to use these new options at the same time.  Any user
+	space app that directly uses the old options should convert to using
+	the new options.
+Who:	Vlad Yasevich <vladislav.yasevich@hp.com>
+
+---------------------------
+
+What:	CONFIG_THERMAL_HWMON
+When:	January 2009
+Why:	This option was introduced just to allow older lm-sensors userspace
+	to keep working over the upgrade to 2.6.26. At the scheduled time of
+	removal fixed lm-sensors (2.x or 3.x) should be readily available.
+Who:	Rene Herman <rene.herman@gmail.com>
+
+---------------------------
+
+What:	Code that is now under CONFIG_WIRELESS_EXT_SYSFS
+	(in net/core/net-sysfs.c)
+When:	After the only user (hal) has seen a release with the patches
+	for enough time, probably some time in 2010.
+Why:	Over 1K .text/.data size reduction, data is available in other
+	ways (ioctls)
+Who:	Johannes Berg <johannes@sipsolutions.net>

Documentation/filesystems/configfs/configfs_example.c

@@ -279,7 +279,7 @@ static struct config_item *simple_children_make_item(struct config_group *group,
 
 	simple_child = kzalloc(sizeof(struct simple_child), GFP_KERNEL);
 	if (!simple_child)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 
 	config_item_init_type_name(&simple_child->item, name,
@@ -366,7 +366,7 @@ static struct config_group *group_children_make_group(struct config_group *group
 	simple_children = kzalloc(sizeof(struct simple_children),
 				  GFP_KERNEL);
 	if (!simple_children)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 
 	config_group_init_type_name(&simple_children->group, name,

Documentation/filesystems/ext4.txt

@@ -13,72 +13,93 @@ Mailing list: linux-ext4@vger.kernel.org
 1. Quick usage instructions:
 ===========================
 
-  - Grab updated e2fsprogs from
-    ftp://ftp.kernel.org/pub/linux/kernel/people/tytso/e2fsprogs-interim/
-    This is a patchset on top of e2fsprogs-1.39, which can be found at
+  - Compile and install the latest version of e2fsprogs (as of this
+    writing version 1.41) from:
+
+    http://sourceforge.net/project/showfiles.php?group_id=2406
+	
+	or
+
     ftp://ftp.kernel.org/pub/linux/kernel/people/tytso/e2fsprogs/
 
-  - It's still mke2fs -j /dev/hda1
+	or grab the latest git repository from:
+
+    git://git.kernel.org/pub/scm/fs/ext2/e2fsprogs.git
+
+  - Create a new filesystem using the ext4dev filesystem type:
+
+    	# mke2fs -t ext4dev /dev/hda1
+
+    Or configure an existing ext3 filesystem to support extents and set
+    the test_fs flag to indicate that it's ok for an in-development
+    filesystem to touch this filesystem:
 
-  - mount /dev/hda1 /wherever -t ext4dev
+	# tune2fs -O extents -E test_fs /dev/hda1
 
-  - To enable extents,
+    If the filesystem was created with 128 byte inodes, it can be
+    converted to use 256 byte for greater efficiency via:
 
-	mount /dev/hda1 /wherever -t ext4dev -o extents
+        # tune2fs -I 256 /dev/hda1
 
-  - The filesystem is compatible with the ext3 driver until you add a file
-    which has extents (ie: `mount -o extents', then create a file).
+    (Note: we currently do not have tools to convert an ext4dev
+    filesystem back to ext3; so please do not do try this on production
+    filesystems.)
 
-    NOTE: The "extents" mount flag is temporary.  It will soon go away and
-    extents will be enabled by the "-o extents" flag to mke2fs or tune2fs
+  - Mounting:
+
+	# mount -t ext4dev /dev/hda1 /wherever
 
   - When comparing performance with other filesystems, remember that
-    ext3/4 by default offers higher data integrity guarantees than most.  So
-    when comparing with a metadata-only journalling filesystem, use `mount -o
-    data=writeback'.  And you might as well use `mount -o nobh' too along
-    with it.  Making the journal larger than the mke2fs default often helps
-    performance with metadata-intensive workloads.
+    ext3/4 by default offers higher data integrity guarantees than most.
+    So when comparing with a metadata-only journalling filesystem, such
+    as ext3, use `mount -o data=writeback'.  And you might as well use
+    `mount -o nobh' too along with it.  Making the journal larger than
+    the mke2fs default often helps performance with metadata-intensive
+    workloads.
 
 2. Features
 ===========
 
 2.1 Currently available
 
-* ability to use filesystems > 16TB
+* ability to use filesystems > 16TB (e2fsprogs support not available yet)
 * extent format reduces metadata overhead (RAM, IO for access, transactions)
 * extent format more robust in face of on-disk corruption due to magics,
 * internal redunancy in tree
-
-2.1 Previously available, soon to be enabled by default by "mkefs.ext4":
-
-* dir_index and resize inode will be on by default
-* large inodes will be used by default for fast EAs, nsec timestamps, etc
+* improved file allocation (multi-block alloc)
+* fix 32000 subdirectory limit
+* nsec timestamps for mtime, atime, ctime, create time
+* inode version field on disk (NFSv4, Lustre)
+* reduced e2fsck time via uninit_bg feature
+* journal checksumming for robustness, performance
+* persistent file preallocation (e.g for streaming media, databases)
+* ability to pack bitmaps and inode tables into larger virtual groups via the
+  flex_bg feature
+* large file support
+* Inode allocation using large virtual block groups via flex_bg
+* delayed allocation
+* large block (up to pagesize) support
+* efficent new ordered mode in JBD2 and ext4(avoid using buffer head to force
+  the ordering)
 
 2.2 Candidate features for future inclusion
 
-There are several under discussion, whether they all make it in is
-partly a function of how much time everyone has to work on them:
+* Online defrag (patches available but not well tested)
+* reduced mke2fs time via lazy itable initialization in conjuction with
+  the uninit_bg feature (capability to do this is available in e2fsprogs
+  but a kernel thread to do lazy zeroing of unused inode table blocks
+  after filesystem is first mounted is required for safety)
 
-* improved file allocation (multi-block alloc, delayed alloc; basically done)
-* fix 32000 subdirectory limit (patch exists, needs some e2fsck work)
-* nsec timestamps for mtime, atime, ctime, create time (patch exists,
-  needs some e2fsck work)
-* inode version field on disk (NFSv4, Lustre; prototype exists)
-* reduced mke2fs/e2fsck time via uninitialized groups (prototype exists)
-* journal checksumming for robustness, performance (prototype exists)
-* persistent file preallocation (e.g for streaming media, databases)
+There are several others under discussion, whether they all make it in is
+partly a function of how much time everyone has to work on them. Features like
+metadata checksumming have been discussed and planned for a bit but no patches
+exist yet so I'm not sure they're in the near-term roadmap.
 
-Features like metadata checksumming have been discussed and planned for
-a bit but no patches exist yet so I'm not sure they're in the near-term
-roadmap.
+The big performance win will come with mballoc, delalloc and flex_bg
+grouping of bitmaps and inode tables.  Some test results available here:
 
-The big performance win will come with mballoc and delalloc.  CFS has
-been using mballoc for a few years already with Lustre, and IBM + Bull
-did a lot of benchmarking on it.  The reason it isn't in the first set of
-patches is partly a manageability issue, and partly because it doesn't
-directly affect the on-disk format (outside of much better allocation)
-so it isn't critical to get into the first round of changes.  I believe
-Alex is working on a new set of patches right now.
+ - http://www.bullopensource.org/ext4/20080530/ffsb-write-2.6.26-rc2.html
+ - http://www.bullopensource.org/ext4/20080530/ffsb-readwrite-2.6.26-rc2.html
 
 3. Options
 ==========
@@ -139,8 +160,16 @@ commit=nrsec	(*)	Ext4 can be told to sync all its data and metadata
 			Setting it to very large values will improve
 			performance.
 
-barrier=1		This enables/disables barriers.  barrier=0 disables
-			it, barrier=1 enables it.
+barrier=<0|1(*)>	This enables/disables the use of write barriers in
+			the jbd code.  barrier=0 disables, barrier=1 enables.
+			This also requires an IO stack which can support
+			barriers, and if jbd gets an error on a barrier
+			write, it will disable again with a warning.
+			Write barriers enforce proper on-disk ordering
+			of journal commits, making volatile disk write caches
+			safe to use, at some performance penalty.  If
+			your disks are battery-backed in one way or another,
+			disabling barriers may safely improve performance.
 
 orlov		(*)	This enables the new Orlov block allocator. It is
 			enabled by default.
@@ -214,9 +243,11 @@ stripe=n		Number of filesystem blocks that mballoc will try
 			to use for allocation size and alignment. For RAID5/6
 			systems this should be the number of data
 			disks *  RAID chunk size in file system blocks.
-
+delalloc	(*)	Deferring block allocation until write-out time.
+nodelalloc		Disable delayed allocation. Blocks are allocation
+			when data is copied from user to page cache.
 Data Mode
----------
+=========
 There are 3 different data modes:
 
 * writeback mode
@@ -228,10 +259,10 @@ typically provide the best ext4 performance.
 
 * ordered mode
 In data=ordered mode, ext4 only officially journals metadata, but it logically
-groups metadata and data blocks into a single unit called a transaction.  When
-it's time to write the new metadata out to disk, the associated data blocks
-are written first.  In general, this mode performs slightly slower than
-writeback but significantly faster than journal mode.
+groups metadata information related to data changes with the data blocks into a
+single unit called a transaction.  When it's time to write the new metadata
+out to disk, the associated data blocks are written first.  In general,
+this mode performs slightly slower than writeback but significantly faster than journal mode.
 
 * journal mode
 data=journal mode provides full data and metadata journaling.  All new data is
@@ -239,7 +270,8 @@ written to the journal first, and then to its final location.
 In the event of a crash, the journal can be replayed, bringing both data and
 metadata into a consistent state.  This mode is the slowest except when data
 needs to be read from and written to disk at the same time where it
-outperforms all others modes.
+outperforms all others modes.  Curently ext4 does not have delayed
+allocation support if this data journalling mode is selected.
 
 References
 ==========
@@ -248,7 +280,8 @@ kernel source:	<file:fs/ext4/>
 		<file:fs/jbd2/>
 
 programs:	http://e2fsprogs.sourceforge.net/
-		http://ext2resize.sourceforge.net
 
 useful links:	http://fedoraproject.org/wiki/ext3-devel
 		http://www.bullopensource.org/ext4/
+		http://ext4.wiki.kernel.org/index.php/Main_Page
+		http://fedoraproject.org/wiki/Features/Ext4

Documentation/filesystems/gfs2-glocks.txt

@@ -0,0 +1,114 @@
+                   Glock internal locking rules
+                  ------------------------------
+
+This documents the basic principles of the glock state machine
+internals. Each glock (struct gfs2_glock in fs/gfs2/incore.h)
+has two main (internal) locks:
+
+ 1. A spinlock (gl_spin) which protects the internal state such
+    as gl_state, gl_target and the list of holders (gl_holders)
+ 2. A non-blocking bit lock, GLF_LOCK, which is used to prevent other
+    threads from making calls to the DLM, etc. at the same time. If a
+    thread takes this lock, it must then call run_queue (usually via the
+    workqueue) when it releases it in order to ensure any pending tasks
+    are completed.
+
+The gl_holders list contains all the queued lock requests (not
+just the holders) associated with the glock. If there are any
+held locks, then they will be contiguous entries at the head
+of the list. Locks are granted in strictly the order that they
+are queued, except for those marked LM_FLAG_PRIORITY which are
+used only during recovery, and even then only for journal locks.
+
+There are three lock states that users of the glock layer can request,
+namely shared (SH), deferred (DF) and exclusive (EX). Those translate
+to the following DLM lock modes:
+
+Glock mode    | DLM lock mode
+------------------------------
+    UN        |    IV/NL  Unlocked (no DLM lock associated with glock) or NL
+    SH        |    PR     (Protected read)
+    DF        |    CW     (Concurrent write)
+    EX        |    EX     (Exclusive)
+
+Thus DF is basically a shared mode which is incompatible with the "normal"
+shared lock mode, SH. In GFS2 the DF mode is used exclusively for direct I/O
+operations. The glocks are basically a lock plus some routines which deal
+with cache management. The following rules apply for the cache:
+
+Glock mode   |  Cache data | Cache Metadata | Dirty Data | Dirty Metadata
+--------------------------------------------------------------------------
+    UN       |     No      |       No       |     No     |      No
+    SH       |     Yes     |       Yes      |     No     |      No
+    DF       |     No      |       Yes      |     No     |      No
+    EX       |     Yes     |       Yes      |     Yes    |      Yes
+
+These rules are implemented using the various glock operations which
+are defined for each type of glock. Not all types of glocks use
+all the modes. Only inode glocks use the DF mode for example.
+
+Table of glock operations and per type constants:
+
+Field            | Purpose
+----------------------------------------------------------------------------
+go_xmote_th      | Called before remote state change (e.g. to sync dirty data)
+go_xmote_bh      | Called after remote state change (e.g. to refill cache)
+go_inval         | Called if remote state change requires invalidating the cache
+go_demote_ok     | Returns boolean value of whether its ok to demote a glock
+                 | (e.g. checks timeout, and that there is no cached data)
+go_lock          | Called for the first local holder of a lock
+go_unlock        | Called on the final local unlock of a lock
+go_dump          | Called to print content of object for debugfs file, or on
+                 | error to dump glock to the log.
+go_type;         | The type of the glock, LM_TYPE_.....
+go_min_hold_time | The minimum hold time
+
+The minimum hold time for each lock is the time after a remote lock
+grant for which we ignore remote demote requests. This is in order to
+prevent a situation where locks are being bounced around the cluster
+from node to node with none of the nodes making any progress. This
+tends to show up most with shared mmaped files which are being written
+to by multiple nodes. By delaying the demotion in response to a
+remote callback, that gives the userspace program time to make
+some progress before the pages are unmapped.
+
+There is a plan to try and remove the go_lock and go_unlock callbacks
+if possible, in order to try and speed up the fast path though the locking.
+Also, eventually we hope to make the glock "EX" mode locally shared
+such that any local locking will be done with the i_mutex as required
+rather than via the glock.
+
+Locking rules for glock operations:
+
+Operation     |  GLF_LOCK bit lock held |  gl_spin spinlock held
+-----------------------------------------------------------------
+go_xmote_th   |       Yes               |       No
+go_xmote_bh   |       Yes               |       No
+go_inval      |       Yes               |       No
+go_demote_ok  |       Sometimes         |       Yes
+go_lock       |       Yes               |       No
+go_unlock     |       Yes               |       No
+go_dump       |       Sometimes         |       Yes
+
+N.B. Operations must not drop either the bit lock or the spinlock
+if its held on entry. go_dump and do_demote_ok must never block.
+Note that go_dump will only be called if the glock's state
+indicates that it is caching uptodate data.
+
+Glock locking order within GFS2:
+
+ 1. i_mutex (if required)
+ 2. Rename glock (for rename only)
+ 3. Inode glock(s)
+    (Parents before children, inodes at "same level" with same parent in
+     lock number order)
+ 4. Rgrp glock(s) (for (de)allocation operations)
+ 5. Transaction glock (via gfs2_trans_begin) for non-read operations
+ 6. Page lock  (always last, very important!)
+
+There are two glocks per inode. One deals with access to the inode
+itself (locking order as above), and the other, known as the iopen
+glock is used in conjunction with the i_nlink field in the inode to
+determine the lifetime of the inode in question. Locking of inodes
+is on a per-inode basis. Locking of rgrps is on a per rgrp basis.
+

Documentation/filesystems/nfs-rdma.txt

@@ -5,7 +5,7 @@
 ################################################################################
 
  Author: NetApp and Open Grid Computing
- Date: April 15, 2008
+ Date: May 29, 2008
 
 Table of Contents
 ~~~~~~~~~~~~~~~~~
@@ -60,16 +60,18 @@ Installation
     The procedures described in this document have been tested with
     distributions from Red Hat's Fedora Project (http://fedora.redhat.com/).
 
-  - Install nfs-utils-1.1.1 or greater on the client
+  - Install nfs-utils-1.1.2 or greater on the client
 
-    An NFS/RDMA mount point can only be obtained by using the mount.nfs
-    command in nfs-utils-1.1.1 or greater. To see which version of mount.nfs
-    you are using, type:
+    An NFS/RDMA mount point can be obtained by using the mount.nfs command in
+    nfs-utils-1.1.2 or greater (nfs-utils-1.1.1 was the first nfs-utils
+    version with support for NFS/RDMA mounts, but for various reasons we
+    recommend using nfs-utils-1.1.2 or greater). To see which version of
+    mount.nfs you are using, type:
 
-    > /sbin/mount.nfs -V
+    $ /sbin/mount.nfs -V
 
-    If the version is less than 1.1.1 or the command does not exist,
-    then you will need to install the latest version of nfs-utils.
+    If the version is less than 1.1.2 or the command does not exist,
+    you should install the latest version of nfs-utils.
 
     Download the latest package from:
 
@@ -77,22 +79,33 @@ Installation
 
     Uncompress the package and follow the installation instructions.
 
-    If you will not be using GSS and NFSv4, the installation process
-    can be simplified by disabling these features when running configure:
+    If you will not need the idmapper and gssd executables (you do not need
+    these to create an NFS/RDMA enabled mount command), the installation
+    process can be simplified by disabling these features when running
+    configure:
 
-    > ./configure --disable-gss --disable-nfsv4
+    $ ./configure --disable-gss --disable-nfsv4
 
-    For more information on this see the package's README and INSTALL files.
+    To build nfs-utils you will need the tcp_wrappers package installed. For
+    more information on this see the package's README and INSTALL files.
 
     After building the nfs-utils package, there will be a mount.nfs binary in
     the utils/mount directory. This binary can be used to initiate NFS v2, v3,
-    or v4 mounts. To initiate a v4 mount, the binary must be called mount.nfs4.
-    The standard technique is to create a symlink called mount.nfs4 to mount.nfs.
+    or v4 mounts. To initiate a v4 mount, the binary must be called
+    mount.nfs4.  The standard technique is to create a symlink called
+    mount.nfs4 to mount.nfs.
 
-    NOTE: mount.nfs and therefore nfs-utils-1.1.1 or greater is only needed
+    This mount.nfs binary should be installed at /sbin/mount.nfs as follows:
+
+    $ sudo cp utils/mount/mount.nfs /sbin/mount.nfs
+
+    In this location, mount.nfs will be invoked automatically for NFS mounts
+    by the system mount commmand.
+
+    NOTE: mount.nfs and therefore nfs-utils-1.1.2 or greater is only needed
     on the NFS client machine. You do not need this specific version of
     nfs-utils on the server. Furthermore, only the mount.nfs command from
-    nfs-utils-1.1.1 is needed on the client.
+    nfs-utils-1.1.2 is needed on the client.
 
   - Install a Linux kernel with NFS/RDMA
 
@@ -156,8 +169,8 @@ Check RDMA and NFS Setup
     this time. For example, if you are using a Mellanox Tavor/Sinai/Arbel
     card:
 
-    > modprobe ib_mthca
-    > modprobe ib_ipoib
+    $ modprobe ib_mthca
+    $ modprobe ib_ipoib
 
     If you are using InfiniBand, make sure there is a Subnet Manager (SM)
     running on the network. If your IB switch has an embedded SM, you can
@@ -166,7 +179,7 @@ Check RDMA and NFS Setup
 
     If an SM is running on your network, you should see the following:
 
-    > cat /sys/class/infiniband/driverX/ports/1/state
+    $ cat /sys/class/infiniband/driverX/ports/1/state
     4: ACTIVE
 
     where driverX is mthca0, ipath5, ehca3, etc.
@@ -174,10 +187,10 @@ Check RDMA and NFS Setup
     To further test the InfiniBand software stack, use IPoIB (this
     assumes you have two IB hosts named host1 and host2):
 
-    host1> ifconfig ib0 a.b.c.x
-    host2> ifconfig ib0 a.b.c.y
-    host1> ping a.b.c.y
-    host2> ping a.b.c.x
+    host1$ ifconfig ib0 a.b.c.x
+    host2$ ifconfig ib0 a.b.c.y
+    host1$ ping a.b.c.y
+    host2$ ping a.b.c.x
 
     For other device types, follow the appropriate procedures.
 
@@ -202,11 +215,11 @@ NFS/RDMA Setup
     /vol0   192.168.0.47(fsid=0,rw,async,insecure,no_root_squash)
     /vol0   192.168.0.0/255.255.255.0(fsid=0,rw,async,insecure,no_root_squash)
 
-    The IP address(es) is(are) the client's IPoIB address for an InfiniBand HCA or the
-    cleint's iWARP address(es) for an RNIC.
+    The IP address(es) is(are) the client's IPoIB address for an InfiniBand
+    HCA or the cleint's iWARP address(es) for an RNIC.
 
-    NOTE: The "insecure" option must be used because the NFS/RDMA client does not
-    use a reserved port.
+    NOTE: The "insecure" option must be used because the NFS/RDMA client does
+    not use a reserved port.
 
  Each time a machine boots:
 
@@ -214,43 +227,45 @@ NFS/RDMA Setup
 
     For InfiniBand using a Mellanox adapter:
 
-    > modprobe ib_mthca
-    > modprobe ib_ipoib
-    > ifconfig ib0 a.b.c.d
+    $ modprobe ib_mthca
+    $ modprobe ib_ipoib
+    $ ifconfig ib0 a.b.c.d
 
     NOTE: use unique addresses for the client and server
 
   - Start the NFS server
 
-    If the NFS/RDMA server was built as a module (CONFIG_SUNRPC_XPRT_RDMA=m in kernel config),
-    load the RDMA transport module:
+    If the NFS/RDMA server was built as a module (CONFIG_SUNRPC_XPRT_RDMA=m in
+    kernel config), load the RDMA transport module:
 
-    > modprobe svcrdma
+    $ modprobe svcrdma
 
-    Regardless of how the server was built (module or built-in), start the server:
+    Regardless of how the server was built (module or built-in), start the
+    server:
 
-    > /etc/init.d/nfs start
+    $ /etc/init.d/nfs start
 
     or
 
-    > service nfs start
+    $ service nfs start
 
     Instruct the server to listen on the RDMA transport:
 
-    > echo rdma 2050 > /proc/fs/nfsd/portlist
+    $ echo rdma 2050 > /proc/fs/nfsd/portlist
 
   - On the client system
 
-    If the NFS/RDMA client was built as a module (CONFIG_SUNRPC_XPRT_RDMA=m in kernel config),
-    load the RDMA client module:
+    If the NFS/RDMA client was built as a module (CONFIG_SUNRPC_XPRT_RDMA=m in
+    kernel config), load the RDMA client module:
 
-    > modprobe xprtrdma.ko
+    $ modprobe xprtrdma.ko
 
-    Regardless of how the client was built (module or built-in), issue the mount.nfs command:
+    Regardless of how the client was built (module or built-in), use this
+    command to mount the NFS/RDMA server:
 
-    > /path/to/your/mount.nfs <IPoIB-server-name-or-address>:/<export> /mnt -i -o rdma,port=2050
+    $ mount -o rdma,port=2050 <IPoIB-server-name-or-address>:/<export> /mnt
 
-    To verify that the mount is using RDMA, run "cat /proc/mounts" and check the
-    "proto" field for the given mount.
+    To verify that the mount is using RDMA, run "cat /proc/mounts" and check
+    the "proto" field for the given mount.
 
   Congratulations! You're using NFS/RDMA!

Documentation/filesystems/proc.txt

@@ -380,28 +380,35 @@ i386 and x86_64 platforms support the new IRQ vector displays.
 Of some interest is the introduction of the /proc/irq directory to 2.4.
 It could be used to set IRQ to CPU affinity, this means that you can "hook" an
 IRQ to only one CPU, or to exclude a CPU of handling IRQs. The contents of the
-irq subdir is one subdir for each IRQ, and one file; prof_cpu_mask
+irq subdir is one subdir for each IRQ, and two files; default_smp_affinity and
+prof_cpu_mask.
 
 For example 
   > ls /proc/irq/
   0  10  12  14  16  18  2  4  6  8  prof_cpu_mask
-  1  11  13  15  17  19  3  5  7  9
+  1  11  13  15  17  19  3  5  7  9  default_smp_affinity
   > ls /proc/irq/0/
   smp_affinity
 
-The contents of the prof_cpu_mask file and each smp_affinity file for each IRQ
-is the same by default:
+smp_affinity is a bitmask, in which you can specify which CPUs can handle the
+IRQ, you can set it by doing:
 
-  > cat /proc/irq/0/smp_affinity 
-  ffffffff
+  > echo 1 > /proc/irq/10/smp_affinity
+
+This means that only the first CPU will handle the IRQ, but you can also echo
+5 which means that only the first and fourth CPU can handle the IRQ.
 
-It's a bitmask, in which you can specify which CPUs can handle the IRQ, you can
-set it by doing:
+The contents of each smp_affinity file is the same by default:
+
+  > cat /proc/irq/0/smp_affinity
+  ffffffff
 
-  > echo 1 > /proc/irq/prof_cpu_mask
+The default_smp_affinity mask applies to all non-active IRQs, which are the
+IRQs which have not yet been allocated/activated, and hence which lack a
+/proc/irq/[0-9]* directory.
 
-This means that only the first CPU will handle the IRQ, but you can also echo 5
-which means that only the first and fourth CPU can handle the IRQ.
+prof_cpu_mask specifies which CPUs are to be profiled by the system wide
+profiler. Default value is ffffffff (all cpus).
 
 The way IRQs are routed is handled by the IO-APIC, and it's Round Robin
 between all the CPUs which are allowed to handle it. As usual the kernel has

Documentation/filesystems/sysfs-pci.txt

@@ -36,6 +36,7 @@ files, each with their own function.
        local_cpus	   nearby CPU mask (cpumask, ro)
        resource		   PCI resource host addresses (ascii, ro)
        resource0..N	   PCI resource N, if present (binary, mmap)
+       resource0_wc..N_wc  PCI WC map resource N, if prefetchable (binary, mmap)
        rom		   PCI ROM resource, if present (binary, ro)
        subsystem_device	   PCI subsystem device (ascii, ro)
        subsystem_vendor	   PCI subsystem vendor (ascii, ro)

Documentation/filesystems/ubifs.txt

@@ -0,0 +1,164 @@
+Introduction
+=============
+
+UBIFS file-system stands for UBI File System. UBI stands for "Unsorted
+Block Images". UBIFS is a flash file system, which means it is designed
+to work with flash devices. It is important to understand, that UBIFS
+is completely different to any traditional file-system in Linux, like
+Ext2, XFS, JFS, etc. UBIFS represents a separate class of file-systems
+which work with MTD devices, not block devices. The other Linux
+file-system of this class is JFFS2.
+
+To make it more clear, here is a small comparison of MTD devices and
+block devices.
+
+1 MTD devices represent flash devices and they consist of eraseblocks of
+  rather large size, typically about 128KiB. Block devices consist of
+  small blocks, typically 512 bytes.
+2 MTD devices support 3 main operations - read from some offset within an
+  eraseblock, write to some offset within an eraseblock, and erase a whole
+  eraseblock. Block  devices support 2 main operations - read a whole
+  block and write a whole block.
+3 The whole eraseblock has to be erased before it becomes possible to
+  re-write its contents. Blocks may be just re-written.
+4 Eraseblocks become worn out after some number of erase cycles -
+  typically 100K-1G for SLC NAND and NOR flashes, and 1K-10K for MLC
+  NAND flashes. Blocks do not have the wear-out property.
+5 Eraseblocks may become bad (only on NAND flashes) and software should
+  deal with this. Blocks on hard drives typically do not become bad,
+  because hardware has mechanisms to substitute bad blocks, at least in
+  modern LBA disks.
+
+It should be quite obvious why UBIFS is very different to traditional
+file-systems.
+
+UBIFS works on top of UBI. UBI is a separate software layer which may be
+found in drivers/mtd/ubi. UBI is basically a volume management and
+wear-leveling layer. It provides so called UBI volumes which is a higher
+level abstraction than a MTD device. The programming model of UBI devices
+is very similar to MTD devices - they still consist of large eraseblocks,
+they have read/write/erase operations, but UBI devices are devoid of
+limitations like wear and bad blocks (items 4 and 5 in the above list).
+
+In a sense, UBIFS is a next generation of JFFS2 file-system, but it is
+very different and incompatible to JFFS2. The following are the main
+differences.
+
+* JFFS2 works on top of MTD devices, UBIFS depends on UBI and works on
+  top of UBI volumes.
+* JFFS2 does not have on-media index and has to build it while mounting,
+  which requires full media scan. UBIFS maintains the FS indexing
+  information on the flash media and does not require full media scan,
+  so it mounts many times faster than JFFS2.
+* JFFS2 is a write-through file-system, while UBIFS supports write-back,
+  which makes UBIFS much faster on writes.
+
+Similarly to JFFS2, UBIFS supports on-the-flight compression which makes
+it possible to fit quite a lot of data to the flash.
+
+Similarly to JFFS2, UBIFS is tolerant of unclean reboots and power-cuts.
+It does not need stuff like ckfs.ext2. UBIFS automatically replays its
+journal and recovers from crashes, ensuring that the on-flash data
+structures are consistent.
+
+UBIFS scales logarithmically (most of the data structures it uses are
+trees), so the mount time and memory consumption do not linearly depend
+on the flash size, like in case of JFFS2. This is because UBIFS
+maintains the FS index on the flash media. However, UBIFS depends on
+UBI, which scales linearly. So overall UBI/UBIFS stack scales linearly.
+Nevertheless, UBI/UBIFS scales considerably better than JFFS2.
+
+The authors of UBIFS believe, that it is possible to develop UBI2 which
+would scale logarithmically as well. UBI2 would support the same API as UBI,
+but it would be binary incompatible to UBI. So UBIFS would not need to be
+changed to use UBI2
+
+
+Mount options
+=============
+
+(*) == default.
+
+norm_unmount (*)	commit on unmount; the journal is committed
+			when the file-system is unmounted so that the
+			next mount does not have to replay the journal
+			and it becomes very fast;
+fast_unmount		do not commit on unmount; this option makes
+			unmount faster, but the next mount slower
+			because of the need to replay the journal.
+
+
+Quick usage instructions
+========================
+
+The UBI volume to mount is specified using "ubiX_Y" or "ubiX:NAME" syntax,
+where "X" is UBI device number, "Y" is UBI volume number, and "NAME" is
+UBI volume name.
+
+Mount volume 0 on UBI device 0 to /mnt/ubifs:
+$ mount -t ubifs ubi0_0 /mnt/ubifs
+
+Mount "rootfs" volume of UBI device 0 to /mnt/ubifs ("rootfs" is volume
+name):
+$ mount -t ubifs ubi0:rootfs /mnt/ubifs
+
+The following is an example of the kernel boot arguments to attach mtd0
+to UBI and mount volume "rootfs":
+ubi.mtd=0 root=ubi0:rootfs rootfstype=ubifs
+
+
+Module Parameters for Debugging
+===============================
+
+When UBIFS has been compiled with debugging enabled, there are 3 module
+parameters that are available to control aspects of testing and debugging.
+The parameters are unsigned integers where each bit controls an option.
+The parameters are:
+
+debug_msgs	Selects which debug messages to display, as follows:
+
+		Message Type				Flag value
+
+		General messages			1
+		Journal messages			2
+		Mount messages				4
+		Commit messages				8
+		LEB search messages			16
+		Budgeting messages			32
+		Garbage collection messages		64
+		Tree Node Cache (TNC) messages		128
+		LEB properties (lprops) messages	256
+		Input/output messages			512
+		Log messages				1024
+		Scan messages				2048
+		Recovery messages			4096
+
+debug_chks	Selects extra checks that UBIFS can do while running:
+
+		Check					Flag value
+
+		General checks				1
+		Check Tree Node Cache (TNC)		2
+		Check indexing tree size		4
+		Check orphan area			8
+		Check old indexing tree			16
+		Check LEB properties (lprops)		32
+		Check leaf nodes and inodes		64
+
+debug_tsts	Selects a mode of testing, as follows:
+
+		Test mode				Flag value
+
+		Force in-the-gaps method		2
+		Failure mode for recovery testing	4
+
+For example, set debug_msgs to 5 to display General messages and Mount
+messages.
+
+
+References
+==========
+
+UBIFS documentation and FAQ/HOWTO at the MTD web site:
+http://www.linux-mtd.infradead.org/doc/ubifs.html
+http://www.linux-mtd.infradead.org/faq/ubifs.html

Documentation/ftrace.txt

@@ -0,0 +1,1360 @@
+		ftrace - Function Tracer
+		========================
+
+Copyright 2008 Red Hat Inc.
+   Author:   Steven Rostedt <srostedt@redhat.com>
+  License:   The GNU Free Documentation License, Version 1.2
+Reviewers:   Elias Oltmanns, Randy Dunlap, Andrew Morton,
+	     John Kacur, and David Teigland.
+
+Written for: 2.6.27-rc1
+
+Introduction
+------------
+
+Ftrace is an internal tracer designed to help out developers and
+designers of systems to find what is going on inside the kernel.
+It can be used for debugging or analyzing latencies and performance
+issues that take place outside of user-space.
+
+Although ftrace is the function tracer, it also includes an
+infrastructure that allows for other types of tracing. Some of the
+tracers that are currently in ftrace include a tracer to trace
+context switches, the time it takes for a high priority task to
+run after it was woken up, the time interrupts are disabled, and
+more (ftrace allows for tracer plugins, which means that the list of
+tracers can always grow).
+
+
+The File System
+---------------
+
+Ftrace uses the debugfs file system to hold the control files as well
+as the files to display output.
+
+To mount the debugfs system:
+
+  # mkdir /debug
+  # mount -t debugfs nodev /debug
+
+(Note: it is more common to mount at /sys/kernel/debug, but for simplicity
+ this document will use /debug)
+
+That's it! (assuming that you have ftrace configured into your kernel)
+
+After mounting the debugfs, you can see a directory called
+"tracing".  This directory contains the control and output files
+of ftrace. Here is a list of some of the key files:
+
+
+ Note: all time values are in microseconds.
+
+  current_tracer : This is used to set or display the current tracer
+		that is configured.
+
+  available_tracers : This holds the different types of tracers that
+		have been compiled into the kernel. The tracers
+		listed here can be configured by echoing their name
+		into current_tracer.
+
+  tracing_enabled : This sets or displays whether the current_tracer
+		is activated and tracing or not. Echo 0 into this
+		file to disable the tracer or 1 to enable it.
+
+  trace : This file holds the output of the trace in a human readable
+		format (described below).
+
+  latency_trace : This file shows the same trace but the information
+		is organized more to display possible latencies
+		in the system (described below).
+
+  trace_pipe : The output is the same as the "trace" file but this
+		file is meant to be streamed with live tracing.
+		Reads from this file will block until new data
+		is retrieved. Unlike the "trace" and "latency_trace"
+		files, this file is a consumer. This means reading
+		from this file causes sequential reads to display
+		more current data. Once data is read from this
+		file, it is consumed, and will not be read
+		again with a sequential read. The "trace" and
+		"latency_trace" files are static, and if the
+		tracer is not adding more data, they will display
+		the same information every time they are read.
+
+  iter_ctrl : This file lets the user control the amount of data
+		that is displayed in one of the above output
+		files.
+
+  trace_max_latency : Some of the tracers record the max latency.
+		For example, the time interrupts are disabled.
+		This time is saved in this file. The max trace
+		will also be stored, and displayed by either
+		"trace" or "latency_trace".  A new max trace will
+		only be recorded if the latency is greater than
+		the value in this file. (in microseconds)
+
+  trace_entries : This sets or displays the number of trace
+		entries each CPU buffer can hold. The tracer buffers
+		are the same size for each CPU. The displayed number
+		is the size of the CPU buffer and not total size. The
+		trace buffers are allocated in pages (blocks of memory
+		that the kernel uses for allocation, usually 4 KB in size).
+		Since each entry is smaller than a page, if the last
+		allocated page has room for more entries than were
+		requested, the rest of the page is used to allocate
+		entries.
+
+		This can only be updated when the current_tracer
+		is set to "none".
+
+		NOTE: It is planned on changing the allocated buffers
+		      from being the number of possible CPUS to
+		      the number of online CPUS.
+
+  tracing_cpumask : This is a mask that lets the user only trace
+		on specified CPUS. The format is a hex string
+		representing the CPUS.
+
+  set_ftrace_filter : When dynamic ftrace is configured in (see the
+		section below "dynamic ftrace"), the code is dynamically
+		modified (code text rewrite) to disable calling of the
+		function profiler (mcount). This lets tracing be configured
+		in with practically no overhead in performance.  This also
+		has a side effect of enabling or disabling specific functions
+		to be traced. Echoing names of functions into this file
+		will limit the trace to only those functions.
+
+  set_ftrace_notrace: This has an effect opposite to that of
+		set_ftrace_filter. Any function that is added here will not
+		be traced. If a function exists in both set_ftrace_filter
+		and set_ftrace_notrace,	the function will _not_ be traced.
+
+  available_filter_functions : When a function is encountered the first
+		time by the dynamic tracer, it is recorded and
+		later the call is converted into a nop. This file
+		lists the functions that have been recorded
+		by the dynamic tracer and these functions can
+		be used to set the ftrace filter by the above
+		"set_ftrace_filter" file. (See the section "dynamic ftrace"
+		below for more details).
+
+
+The Tracers
+-----------
+
+Here is the list of current tracers that may be configured.
+
+  ftrace - function tracer that uses mcount to trace all functions.
+
+  sched_switch - traces the context switches between tasks.
+
+  irqsoff - traces the areas that disable interrupts and saves
+  		the trace with the longest max latency.
+		See tracing_max_latency.  When a new max is recorded,
+		it replaces the old trace. It is best to view this
+		trace via the latency_trace file.
+
+  preemptoff - Similar to irqsoff but traces and records the amount of
+		time for which preemption is disabled.
+
+  preemptirqsoff - Similar to irqsoff and preemptoff, but traces and
+		 records the largest time for which irqs and/or preemption
+		 is disabled.
+
+  wakeup - Traces and records the max latency that it takes for
+		the highest priority task to get scheduled after
+		it has been woken up.
+
+  none - This is not a tracer. To remove all tracers from tracing
+		simply echo "none" into current_tracer.
+
+
+Examples of using the tracer
+----------------------------
+
+Here are typical examples of using the tracers when controlling them only
+with the debugfs interface (without using any user-land utilities).
+
+Output format:
+--------------
+
+Here is an example of the output format of the file "trace"
+
+                             --------
+# tracer: ftrace
+#
+#           TASK-PID   CPU#    TIMESTAMP  FUNCTION
+#              | |      |          |         |
+            bash-4251  [01] 10152.583854: path_put <-path_walk
+            bash-4251  [01] 10152.583855: dput <-path_put
+            bash-4251  [01] 10152.583855: _atomic_dec_and_lock <-dput
+                             --------
+
+A header is printed with the tracer name that is represented by the trace.
+In this case the tracer is "ftrace". Then a header showing the format. Task
+name "bash", the task PID "4251", the CPU that it was running on
+"01", the timestamp in <secs>.<usecs> format, the function name that was
+traced "path_put" and the parent function that called this function
+"path_walk". The timestamp is the time at which the function was
+entered.
+
+The sched_switch tracer also includes tracing of task wakeups and
+context switches.
+
+     ksoftirqd/1-7     [01]  1453.070013:      7:115:R   +  2916:115:S
+     ksoftirqd/1-7     [01]  1453.070013:      7:115:R   +    10:115:S
+     ksoftirqd/1-7     [01]  1453.070013:      7:115:R ==>    10:115:R
+        events/1-10    [01]  1453.070013:     10:115:S ==>  2916:115:R
+     kondemand/1-2916  [01]  1453.070013:   2916:115:S ==>     7:115:R
+     ksoftirqd/1-7     [01]  1453.070013:      7:115:S ==>     0:140:R
+
+Wake ups are represented by a "+" and the context switches are shown as
+"==>".  The format is:
+
+ Context switches:
+
+       Previous task              Next Task
+
+  <pid>:<prio>:<state>  ==>  <pid>:<prio>:<state>
+
+ Wake ups:
+
+       Current task               Task waking up
+
+  <pid>:<prio>:<state>    +  <pid>:<prio>:<state>
+
+The prio is the internal kernel priority, which is the inverse of the
+priority that is usually displayed by user-space tools. Zero represents
+the highest priority (99). Prio 100 starts the "nice" priorities with
+100 being equal to nice -20 and 139 being nice 19. The prio "140" is
+reserved for the idle task which is the lowest priority thread (pid 0).
+
+
+Latency trace format
+--------------------
+
+For traces that display latency times, the latency_trace file gives
+somewhat more information to see why a latency happened. Here is a typical
+trace.
+
+# tracer: irqsoff
+#
+irqsoff latency trace v1.1.5 on 2.6.26-rc8
+--------------------------------------------------------------------
+ latency: 97 us, #3/3, CPU#0 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:2)
+    -----------------
+    | task: swapper-0 (uid:0 nice:0 policy:0 rt_prio:0)
+    -----------------
+ => started at: apic_timer_interrupt
+ => ended at:   do_softirq
+
+#                _------=> CPU#
+#               / _-----=> irqs-off
+#              | / _----=> need-resched
+#              || / _---=> hardirq/softirq
+#              ||| / _--=> preempt-depth
+#              |||| /
+#              |||||     delay
+#  cmd     pid ||||| time  |   caller
+#     \   /    |||||   \   |   /
+  <idle>-0     0d..1    0us+: trace_hardirqs_off_thunk (apic_timer_interrupt)
+  <idle>-0     0d.s.   97us : __do_softirq (do_softirq)
+  <idle>-0     0d.s1   98us : trace_hardirqs_on (do_softirq)
+
+
+
+This shows that the current tracer is "irqsoff" tracing the time for which
+interrupts were disabled. It gives the trace version and the version
+of the kernel upon which this was executed on (2.6.26-rc8). Then it displays
+the max latency in microsecs (97 us). The number of trace entries displayed
+and the total number recorded (both are three: #3/3). The type of
+preemption that was used (PREEMPT). VP, KP, SP, and HP are always zero
+and are reserved for later use. #P is the number of online CPUS (#P:2).
+
+The task is the process that was running when the latency occurred.
+(swapper pid: 0).
+
+The start and stop (the functions in which the interrupts were disabled and
+enabled respectively) that caused the latencies:
+
+  apic_timer_interrupt is where the interrupts were disabled.
+  do_softirq is where they were enabled again.
+
+The next lines after the header are the trace itself. The header
+explains which is which.
+
+  cmd: The name of the process in the trace.
+
+  pid: The PID of that process.
+
+  CPU#: The CPU which the process was running on.
+
+  irqs-off: 'd' interrupts are disabled. '.' otherwise.
+
+  need-resched: 'N' task need_resched is set, '.' otherwise.
+
+  hardirq/softirq:
+	'H' - hard irq occurred inside a softirq.
+	'h' - hard irq is running
+	's' - soft irq is running
+	'.' - normal context.
+
+  preempt-depth: The level of preempt_disabled
+
+The above is mostly meaningful for kernel developers.
+
+  time: This differs from the trace file output. The trace file output
+	includes an absolute timestamp. The timestamp used by the
+	latency_trace file is relative to the start of the trace.
+
+  delay: This is just to help catch your eye a bit better. And
+	needs to be fixed to be only relative to the same CPU.
+	The marks are determined by the difference between this
+	current trace and the next trace.
+	 '!' - greater than preempt_mark_thresh (default 100)
+	 '+' - greater than 1 microsecond
+	 ' ' - less than or equal to 1 microsecond.
+
+  The rest is the same as the 'trace' file.
+
+
+iter_ctrl
+---------
+
+The iter_ctrl file is used to control what gets printed in the trace
+output. To see what is available, simply cat the file:
+
+  cat /debug/tracing/iter_ctrl
+  print-parent nosym-offset nosym-addr noverbose noraw nohex nobin \
+ noblock nostacktrace nosched-tree
+
+To disable one of the options, echo in the option prepended with "no".
+
+  echo noprint-parent > /debug/tracing/iter_ctrl
+
+To enable an option, leave off the "no".
+
+  echo sym-offset > /debug/tracing/iter_ctrl
+
+Here are the available options:
+
+  print-parent - On function traces, display the calling function
+		as well as the function being traced.
+
+  print-parent:
+   bash-4000  [01]  1477.606694: simple_strtoul <-strict_strtoul
+
+  noprint-parent:
+   bash-4000  [01]  1477.606694: simple_strtoul
+
+
+  sym-offset - Display not only the function name, but also the offset
+		in the function. For example, instead of seeing just
+		"ktime_get", you will see "ktime_get+0xb/0x20".
+
+  sym-offset:
+   bash-4000  [01]  1477.606694: simple_strtoul+0x6/0xa0
+
+  sym-addr - this will also display the function address as well as
+		the function name.
+
+  sym-addr:
+   bash-4000  [01]  1477.606694: simple_strtoul <c0339346>
+
+  verbose - This deals with the latency_trace file.
+
+    bash  4000 1 0 00000000 00010a95 [58127d26] 1720.415ms \
+    (+0.000ms): simple_strtoul (strict_strtoul)
+
+  raw - This will display raw numbers. This option is best for use with
+	user applications that can translate the raw numbers better than
+	having it done in the kernel.
+
+  hex - Similar to raw, but the numbers will be in a hexadecimal format.
+
+  bin - This will print out the formats in raw binary.
+
+  block - TBD (needs update)
+
+  stacktrace - This is one of the options that changes the trace itself.
+		When a trace is recorded, so is the stack of functions.
+		This allows for back traces of trace sites.
+
+  sched-tree - TBD (any users??)
+
+
+sched_switch
+------------
+
+This tracer simply records schedule switches. Here is an example
+of how to use it.
+
+ # echo sched_switch > /debug/tracing/current_tracer
+ # echo 1 > /debug/tracing/tracing_enabled
+ # sleep 1
+ # echo 0 > /debug/tracing/tracing_enabled
+ # cat /debug/tracing/trace
+
+# tracer: sched_switch
+#
+#           TASK-PID   CPU#    TIMESTAMP  FUNCTION
+#              | |      |          |         |
+            bash-3997  [01]   240.132281:   3997:120:R   +  4055:120:R
+            bash-3997  [01]   240.132284:   3997:120:R ==>  4055:120:R
+           sleep-4055  [01]   240.132371:   4055:120:S ==>  3997:120:R
+            bash-3997  [01]   240.132454:   3997:120:R   +  4055:120:S
+            bash-3997  [01]   240.132457:   3997:120:R ==>  4055:120:R
+           sleep-4055  [01]   240.132460:   4055:120:D ==>  3997:120:R
+            bash-3997  [01]   240.132463:   3997:120:R   +  4055:120:D
+            bash-3997  [01]   240.132465:   3997:120:R ==>  4055:120:R
+          <idle>-0     [00]   240.132589:      0:140:R   +     4:115:S
+          <idle>-0     [00]   240.132591:      0:140:R ==>     4:115:R
+     ksoftirqd/0-4     [00]   240.132595:      4:115:S ==>     0:140:R
+          <idle>-0     [00]   240.132598:      0:140:R   +     4:115:S
+          <idle>-0     [00]   240.132599:      0:140:R ==>     4:115:R
+     ksoftirqd/0-4     [00]   240.132603:      4:115:S ==>     0:140:R
+           sleep-4055  [01]   240.133058:   4055:120:S ==>  3997:120:R
+ [...]
+
+
+As we have discussed previously about this format, the header shows
+the name of the trace and points to the options. The "FUNCTION"
+is a misnomer since here it represents the wake ups and context
+switches.
+
+The sched_switch file only lists the wake ups (represented with '+')
+and context switches ('==>') with the previous task or current task
+first followed by the next task or task waking up. The format for both
+of these is PID:KERNEL-PRIO:TASK-STATE. Remember that the KERNEL-PRIO
+is the inverse of the actual priority with zero (0) being the highest
+priority and the nice values starting at 100 (nice -20). Below is
+a quick chart to map the kernel priority to user land priorities.
+
+  Kernel priority: 0 to 99    ==> user RT priority 99 to 0
+  Kernel priority: 100 to 139 ==> user nice -20 to 19
+  Kernel priority: 140        ==> idle task priority
+
+The task states are:
+
+ R - running : wants to run, may not actually be running
+ S - sleep   : process is waiting to be woken up (handles signals)
+ D - disk sleep (uninterruptible sleep) : process must be woken up
+					(ignores signals)
+ T - stopped : process suspended
+ t - traced  : process is being traced (with something like gdb)
+ Z - zombie  : process waiting to be cleaned up
+ X - unknown
+
+
+ftrace_enabled
+--------------
+
+The following tracers (listed below) give different output depending
+on whether or not the sysctl ftrace_enabled is set. To set ftrace_enabled,
+one can either use the sysctl function or set it via the proc
+file system interface.
+
+  sysctl kernel.ftrace_enabled=1
+
+ or
+
+  echo 1 > /proc/sys/kernel/ftrace_enabled
+
+To disable ftrace_enabled simply replace the '1' with '0' in
+the above commands.
+
+When ftrace_enabled is set the tracers will also record the functions
+that are within the trace. The descriptions of the tracers
+will also show an example with ftrace enabled.
+
+
+irqsoff
+-------
+
+When interrupts are disabled, the CPU can not react to any other
+external event (besides NMIs and SMIs). This prevents the timer
+interrupt from triggering or the mouse interrupt from letting the
+kernel know of a new mouse event. The result is a latency with the
+reaction time.
+
+The irqsoff tracer tracks the time for which interrupts are disabled.
+When a new maximum latency is hit, the tracer saves the trace leading up
+to that latency point so that every time a new maximum is reached, the old
+saved trace is discarded and the new trace is saved.
+
+To reset the maximum, echo 0 into tracing_max_latency. Here is an
+example:
+
+ # echo irqsoff > /debug/tracing/current_tracer
+ # echo 0 > /debug/tracing/tracing_max_latency
+ # echo 1 > /debug/tracing/tracing_enabled
+ # ls -ltr
+ [...]
+ # echo 0 > /debug/tracing/tracing_enabled
+ # cat /debug/tracing/latency_trace
+# tracer: irqsoff
+#
+irqsoff latency trace v1.1.5 on 2.6.26
+--------------------------------------------------------------------
+ latency: 12 us, #3/3, CPU#1 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:2)
+    -----------------
+    | task: bash-3730 (uid:0 nice:0 policy:0 rt_prio:0)
+    -----------------
+ => started at: sys_setpgid
+ => ended at:   sys_setpgid
+
+#                _------=> CPU#
+#               / _-----=> irqs-off
+#              | / _----=> need-resched
+#              || / _---=> hardirq/softirq
+#              ||| / _--=> preempt-depth
+#              |||| /
+#              |||||     delay
+#  cmd     pid ||||| time  |   caller
+#     \   /    |||||   \   |   /
+    bash-3730  1d...    0us : _write_lock_irq (sys_setpgid)
+    bash-3730  1d..1    1us+: _write_unlock_irq (sys_setpgid)
+    bash-3730  1d..2   14us : trace_hardirqs_on (sys_setpgid)
+
+
+Here we see that that we had a latency of 12 microsecs (which is
+very good). The _write_lock_irq in sys_setpgid disabled interrupts.
+The difference between the 12 and the displayed timestamp 14us occurred
+because the clock was incremented between the time of recording the max
+latency and the time of recording the function that had that latency.
+
+Note the above example had ftrace_enabled not set. If we set the
+ftrace_enabled, we get a much larger output:
+
+# tracer: irqsoff
+#
+irqsoff latency trace v1.1.5 on 2.6.26-rc8
+--------------------------------------------------------------------
+ latency: 50 us, #101/101, CPU#0 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:2)
+    -----------------
+    | task: ls-4339 (uid:0 nice:0 policy:0 rt_prio:0)
+    -----------------
+ => started at: __alloc_pages_internal
+ => ended at:   __alloc_pages_internal
+
+#                _------=> CPU#
+#               / _-----=> irqs-off
+#              | / _----=> need-resched
+#              || / _---=> hardirq/softirq
+#              ||| / _--=> preempt-depth
+#              |||| /
+#              |||||     delay
+#  cmd     pid ||||| time  |   caller
+#     \   /    |||||   \   |   /
+      ls-4339  0...1    0us+: get_page_from_freelist (__alloc_pages_internal)
+      ls-4339  0d..1    3us : rmqueue_bulk (get_page_from_freelist)
+      ls-4339  0d..1    3us : _spin_lock (rmqueue_bulk)
+      ls-4339  0d..1    4us : add_preempt_count (_spin_lock)
+      ls-4339  0d..2    4us : __rmqueue (rmqueue_bulk)
+      ls-4339  0d..2    5us : __rmqueue_smallest (__rmqueue)
+      ls-4339  0d..2    5us : __mod_zone_page_state (__rmqueue_smallest)
+      ls-4339  0d..2    6us : __rmqueue (rmqueue_bulk)
+      ls-4339  0d..2    6us : __rmqueue_smallest (__rmqueue)
+      ls-4339  0d..2    7us : __mod_zone_page_state (__rmqueue_smallest)
+      ls-4339  0d..2    7us : __rmqueue (rmqueue_bulk)
+      ls-4339  0d..2    8us : __rmqueue_smallest (__rmqueue)
+[...]
+      ls-4339  0d..2   46us : __rmqueue_smallest (__rmqueue)
+      ls-4339  0d..2   47us : __mod_zone_page_state (__rmqueue_smallest)
+      ls-4339  0d..2   47us : __rmqueue (rmqueue_bulk)
+      ls-4339  0d..2   48us : __rmqueue_smallest (__rmqueue)
+      ls-4339  0d..2   48us : __mod_zone_page_state (__rmqueue_smallest)
+      ls-4339  0d..2   49us : _spin_unlock (rmqueue_bulk)
+      ls-4339  0d..2   49us : sub_preempt_count (_spin_unlock)
+      ls-4339  0d..1   50us : get_page_from_freelist (__alloc_pages_internal)
+      ls-4339  0d..2   51us : trace_hardirqs_on (__alloc_pages_internal)
+
+
+
+Here we traced a 50 microsecond latency. But we also see all the
+functions that were called during that time. Note that by enabling
+function tracing, we incur an added overhead. This overhead may
+extend the latency times. But nevertheless, this trace has provided
+some very helpful debugging information.
+
+
+preemptoff
+----------
+
+When preemption is disabled, we may be able to receive interrupts but
+the task cannot be preempted and a higher priority task must wait
+for preemption to be enabled again before it can preempt a lower
+priority task.
+
+The preemptoff tracer traces the places that disable preemption.
+Like the irqsoff tracer, it records the maximum latency for which preemption
+was disabled. The control of preemptoff tracer is much like the irqsoff
+tracer.
+
+ # echo preemptoff > /debug/tracing/current_tracer
+ # echo 0 > /debug/tracing/tracing_max_latency
+ # echo 1 > /debug/tracing/tracing_enabled
+ # ls -ltr
+ [...]
+ # echo 0 > /debug/tracing/tracing_enabled
+ # cat /debug/tracing/latency_trace
+# tracer: preemptoff
+#
+preemptoff latency trace v1.1.5 on 2.6.26-rc8
+--------------------------------------------------------------------
+ latency: 29 us, #3/3, CPU#0 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:2)
+    -----------------
+    | task: sshd-4261 (uid:0 nice:0 policy:0 rt_prio:0)
+    -----------------
+ => started at: do_IRQ
+ => ended at:   __do_softirq
+
+#                _------=> CPU#
+#               / _-----=> irqs-off
+#              | / _----=> need-resched
+#              || / _---=> hardirq/softirq
+#              ||| / _--=> preempt-depth
+#              |||| /
+#              |||||     delay
+#  cmd     pid ||||| time  |   caller
+#     \   /    |||||   \   |   /
+    sshd-4261  0d.h.    0us+: irq_enter (do_IRQ)
+    sshd-4261  0d.s.   29us : _local_bh_enable (__do_softirq)
+    sshd-4261  0d.s1   30us : trace_preempt_on (__do_softirq)
+
+
+This has some more changes. Preemption was disabled when an interrupt
+came in (notice the 'h'), and was enabled while doing a softirq.
+(notice the 's'). But we also see that interrupts have been disabled
+when entering the preempt off section and leaving it (the 'd').
+We do not know if interrupts were enabled in the mean time.
+
+# tracer: preemptoff
+#
+preemptoff latency trace v1.1.5 on 2.6.26-rc8
+--------------------------------------------------------------------
+ latency: 63 us, #87/87, CPU#0 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:2)
+    -----------------
+    | task: sshd-4261 (uid:0 nice:0 policy:0 rt_prio:0)
+    -----------------
+ => started at: remove_wait_queue
+ => ended at:   __do_softirq
+
+#                _------=> CPU#
+#               / _-----=> irqs-off
+#              | / _----=> need-resched
+#              || / _---=> hardirq/softirq
+#              ||| / _--=> preempt-depth
+#              |||| /
+#              |||||     delay
+#  cmd     pid ||||| time  |   caller
+#     \   /    |||||   \   |   /
+    sshd-4261  0d..1    0us : _spin_lock_irqsave (remove_wait_queue)
+    sshd-4261  0d..1    1us : _spin_unlock_irqrestore (remove_wait_queue)
+    sshd-4261  0d..1    2us : do_IRQ (common_interrupt)
+    sshd-4261  0d..1    2us : irq_enter (do_IRQ)
+    sshd-4261  0d..1    2us : idle_cpu (irq_enter)
+    sshd-4261  0d..1    3us : add_preempt_count (irq_enter)
+    sshd-4261  0d.h1    3us : idle_cpu (irq_enter)
+    sshd-4261  0d.h.    4us : handle_fasteoi_irq (do_IRQ)
+[...]
+    sshd-4261  0d.h.   12us : add_preempt_count (_spin_lock)
+    sshd-4261  0d.h1   12us : ack_ioapic_quirk_irq (handle_fasteoi_irq)
+    sshd-4261  0d.h1   13us : move_native_irq (ack_ioapic_quirk_irq)
+    sshd-4261  0d.h1   13us : _spin_unlock (handle_fasteoi_irq)
+    sshd-4261  0d.h1   14us : sub_preempt_count (_spin_unlock)
+    sshd-4261  0d.h1   14us : irq_exit (do_IRQ)
+    sshd-4261  0d.h1   15us : sub_preempt_count (irq_exit)
+    sshd-4261  0d..2   15us : do_softirq (irq_exit)
+    sshd-4261  0d...   15us : __do_softirq (do_softirq)
+    sshd-4261  0d...   16us : __local_bh_disable (__do_softirq)
+    sshd-4261  0d...   16us+: add_preempt_count (__local_bh_disable)
+    sshd-4261  0d.s4   20us : add_preempt_count (__local_bh_disable)
+    sshd-4261  0d.s4   21us : sub_preempt_count (local_bh_enable)
+    sshd-4261  0d.s5   21us : sub_preempt_count (local_bh_enable)
+[...]
+    sshd-4261  0d.s6   41us : add_preempt_count (__local_bh_disable)
+    sshd-4261  0d.s6   42us : sub_preempt_count (local_bh_enable)
+    sshd-4261  0d.s7   42us : sub_preempt_count (local_bh_enable)
+    sshd-4261  0d.s5   43us : add_preempt_count (__local_bh_disable)
+    sshd-4261  0d.s5   43us : sub_preempt_count (local_bh_enable_ip)
+    sshd-4261  0d.s6   44us : sub_preempt_count (local_bh_enable_ip)
+    sshd-4261  0d.s5   44us : add_preempt_count (__local_bh_disable)
+    sshd-4261  0d.s5   45us : sub_preempt_count (local_bh_enable)
+[...]
+    sshd-4261  0d.s.   63us : _local_bh_enable (__do_softirq)
+    sshd-4261  0d.s1   64us : trace_preempt_on (__do_softirq)
+
+
+The above is an example of the preemptoff trace with ftrace_enabled
+set. Here we see that interrupts were disabled the entire time.
+The irq_enter code lets us know that we entered an interrupt 'h'.
+Before that, the functions being traced still show that it is not
+in an interrupt, but we can see from the functions themselves that
+this is not the case.
+
+Notice that __do_softirq when called does not have a preempt_count.
+It may seem that we missed a preempt enabling. What really happened
+is that the preempt count is held on the thread's stack and we
+switched to the softirq stack (4K stacks in effect). The code
+does not copy the preempt count, but because interrupts are disabled,
+we do not need to worry about it. Having a tracer like this is good
+for letting people know what really happens inside the kernel.
+
+
+preemptirqsoff
+--------------
+
+Knowing the locations that have interrupts disabled or preemption
+disabled for the longest times is helpful. But sometimes we would
+like to know when either preemption and/or interrupts are disabled.
+
+Consider the following code:
+
+    local_irq_disable();
+    call_function_with_irqs_off();
+    preempt_disable();
+    call_function_with_irqs_and_preemption_off();
+    local_irq_enable();
+    call_function_with_preemption_off();
+    preempt_enable();
+
+The irqsoff tracer will record the total length of
+call_function_with_irqs_off() and
+call_function_with_irqs_and_preemption_off().
+
+The preemptoff tracer will record the total length of
+call_function_with_irqs_and_preemption_off() and
+call_function_with_preemption_off().
+
+But neither will trace the time that interrupts and/or preemption
+is disabled. This total time is the time that we can not schedule.
+To record this time, use the preemptirqsoff tracer.
+
+Again, using this trace is much like the irqsoff and preemptoff tracers.
+
+ # echo preemptirqsoff > /debug/tracing/current_tracer
+ # echo 0 > /debug/tracing/tracing_max_latency
+ # echo 1 > /debug/tracing/tracing_enabled
+ # ls -ltr
+ [...]
+ # echo 0 > /debug/tracing/tracing_enabled
+ # cat /debug/tracing/latency_trace
+# tracer: preemptirqsoff
+#
+preemptirqsoff latency trace v1.1.5 on 2.6.26-rc8
+--------------------------------------------------------------------
+ latency: 293 us, #3/3, CPU#0 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:2)
+    -----------------
+    | task: ls-4860 (uid:0 nice:0 policy:0 rt_prio:0)
+    -----------------
+ => started at: apic_timer_interrupt
+ => ended at:   __do_softirq
+
+#                _------=> CPU#
+#               / _-----=> irqs-off
+#              | / _----=> need-resched
+#              || / _---=> hardirq/softirq
+#              ||| / _--=> preempt-depth
+#              |||| /
+#              |||||     delay
+#  cmd     pid ||||| time  |   caller
+#     \   /    |||||   \   |   /
+      ls-4860  0d...    0us!: trace_hardirqs_off_thunk (apic_timer_interrupt)
+      ls-4860  0d.s.  294us : _local_bh_enable (__do_softirq)
+      ls-4860  0d.s1  294us : trace_preempt_on (__do_softirq)
+
+
+
+The trace_hardirqs_off_thunk is called from assembly on x86 when
+interrupts are disabled in the assembly code. Without the function
+tracing, we do not know if interrupts were enabled within the preemption
+points. We do see that it started with preemption enabled.
+
+Here is a trace with ftrace_enabled set:
+
+
+# tracer: preemptirqsoff
+#
+preemptirqsoff latency trace v1.1.5 on 2.6.26-rc8
+--------------------------------------------------------------------
+ latency: 105 us, #183/183, CPU#0 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:2)
+    -----------------
+    | task: sshd-4261 (uid:0 nice:0 policy:0 rt_prio:0)
+    -----------------
+ => started at: write_chan
+ => ended at:   __do_softirq
+
+#                _------=> CPU#
+#               / _-----=> irqs-off
+#              | / _----=> need-resched
+#              || / _---=> hardirq/softirq
+#              ||| / _--=> preempt-depth
+#              |||| /
+#              |||||     delay
+#  cmd     pid ||||| time  |   caller
+#     \   /    |||||   \   |   /
+      ls-4473  0.N..    0us : preempt_schedule (write_chan)
+      ls-4473  0dN.1    1us : _spin_lock (schedule)
+      ls-4473  0dN.1    2us : add_preempt_count (_spin_lock)
+      ls-4473  0d..2    2us : put_prev_task_fair (schedule)
+[...]
+      ls-4473  0d..2   13us : set_normalized_timespec (ktime_get_ts)
+      ls-4473  0d..2   13us : __switch_to (schedule)
+    sshd-4261  0d..2   14us : finish_task_switch (schedule)
+    sshd-4261  0d..2   14us : _spin_unlock_irq (finish_task_switch)
+    sshd-4261  0d..1   15us : add_preempt_count (_spin_lock_irqsave)
+    sshd-4261  0d..2   16us : _spin_unlock_irqrestore (hrtick_set)
+    sshd-4261  0d..2   16us : do_IRQ (common_interrupt)
+    sshd-4261  0d..2   17us : irq_enter (do_IRQ)
+    sshd-4261  0d..2   17us : idle_cpu (irq_enter)
+    sshd-4261  0d..2   18us : add_preempt_count (irq_enter)
+    sshd-4261  0d.h2   18us : idle_cpu (irq_enter)
+    sshd-4261  0d.h.   18us : handle_fasteoi_irq (do_IRQ)
+    sshd-4261  0d.h.   19us : _spin_lock (handle_fasteoi_irq)
+    sshd-4261  0d.h.   19us : add_preempt_count (_spin_lock)
+    sshd-4261  0d.h1   20us : _spin_unlock (handle_fasteoi_irq)
+    sshd-4261  0d.h1   20us : sub_preempt_count (_spin_unlock)
+[...]
+    sshd-4261  0d.h1   28us : _spin_unlock (handle_fasteoi_irq)
+    sshd-4261  0d.h1   29us : sub_preempt_count (_spin_unlock)
+    sshd-4261  0d.h2   29us : irq_exit (do_IRQ)
+    sshd-4261  0d.h2   29us : sub_preempt_count (irq_exit)
+    sshd-4261  0d..3   30us : do_softirq (irq_exit)
+    sshd-4261  0d...   30us : __do_softirq (do_softirq)
+    sshd-4261  0d...   31us : __local_bh_disable (__do_softirq)
+    sshd-4261  0d...   31us+: add_preempt_count (__local_bh_disable)
+    sshd-4261  0d.s4   34us : add_preempt_count (__local_bh_disable)
+[...]
+    sshd-4261  0d.s3   43us : sub_preempt_count (local_bh_enable_ip)
+    sshd-4261  0d.s4   44us : sub_preempt_count (local_bh_enable_ip)
+    sshd-4261  0d.s3   44us : smp_apic_timer_interrupt (apic_timer_interrupt)
+    sshd-4261  0d.s3   45us : irq_enter (smp_apic_timer_interrupt)
+    sshd-4261  0d.s3   45us : idle_cpu (irq_enter)
+    sshd-4261  0d.s3   46us : add_preempt_count (irq_enter)
+    sshd-4261  0d.H3   46us : idle_cpu (irq_enter)
+    sshd-4261  0d.H3   47us : hrtimer_interrupt (smp_apic_timer_interrupt)
+    sshd-4261  0d.H3   47us : ktime_get (hrtimer_interrupt)
+[...]
+    sshd-4261  0d.H3   81us : tick_program_event (hrtimer_interrupt)
+    sshd-4261  0d.H3   82us : ktime_get (tick_program_event)
+    sshd-4261  0d.H3   82us : ktime_get_ts (ktime_get)
+    sshd-4261  0d.H3   83us : getnstimeofday (ktime_get_ts)
+    sshd-4261  0d.H3   83us : set_normalized_timespec (ktime_get_ts)
+    sshd-4261  0d.H3   84us : clockevents_program_event (tick_program_event)
+    sshd-4261  0d.H3   84us : lapic_next_event (clockevents_program_event)
+    sshd-4261  0d.H3   85us : irq_exit (smp_apic_timer_interrupt)
+    sshd-4261  0d.H3   85us : sub_preempt_count (irq_exit)
+    sshd-4261  0d.s4   86us : sub_preempt_count (irq_exit)
+    sshd-4261  0d.s3   86us : add_preempt_count (__local_bh_disable)
+[...]
+    sshd-4261  0d.s1   98us : sub_preempt_count (net_rx_action)
+    sshd-4261  0d.s.   99us : add_preempt_count (_spin_lock_irq)
+    sshd-4261  0d.s1   99us+: _spin_unlock_irq (run_timer_softirq)
+    sshd-4261  0d.s.  104us : _local_bh_enable (__do_softirq)
+    sshd-4261  0d.s.  104us : sub_preempt_count (_local_bh_enable)
+    sshd-4261  0d.s.  105us : _local_bh_enable (__do_softirq)
+    sshd-4261  0d.s1  105us : trace_preempt_on (__do_softirq)
+
+
+This is a very interesting trace. It started with the preemption of
+the ls task. We see that the task had the "need_resched" bit set
+via the 'N' in the trace.  Interrupts were disabled before the spin_lock
+at the beginning of the trace. We see that a schedule took place to run
+sshd.  When the interrupts were enabled, we took an interrupt.
+On return from the interrupt handler, the softirq ran. We took another
+interrupt while running the softirq as we see from the capital 'H'.
+
+
+wakeup
+------
+
+In a Real-Time environment it is very important to know the wakeup
+time it takes for the highest priority task that is woken up to the
+time that it executes. This is also known as "schedule latency".
+I stress the point that this is about RT tasks. It is also important
+to know the scheduling latency of non-RT tasks, but the average
+schedule latency is better for non-RT tasks. Tools like
+LatencyTop are more appropriate for such measurements.
+
+Real-Time environments are interested in the worst case latency.
+That is the longest latency it takes for something to happen, and
+not the average. We can have a very fast scheduler that may only
+have a large latency once in a while, but that would not work well
+with Real-Time tasks.  The wakeup tracer was designed to record
+the worst case wakeups of RT tasks. Non-RT tasks are not recorded
+because the tracer only records one worst case and tracing non-RT
+tasks that are unpredictable will overwrite the worst case latency
+of RT tasks.
+
+Since this tracer only deals with RT tasks, we will run this slightly
+differently than we did with the previous tracers. Instead of performing
+an 'ls', we will run 'sleep 1' under 'chrt' which changes the
+priority of the task.
+
+ # echo wakeup > /debug/tracing/current_tracer
+ # echo 0 > /debug/tracing/tracing_max_latency
+ # echo 1 > /debug/tracing/tracing_enabled
+ # chrt -f 5 sleep 1
+ # echo 0 > /debug/tracing/tracing_enabled
+ # cat /debug/tracing/latency_trace
+# tracer: wakeup
+#
+wakeup latency trace v1.1.5 on 2.6.26-rc8
+--------------------------------------------------------------------
+ latency: 4 us, #2/2, CPU#1 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:2)
+    -----------------
+    | task: sleep-4901 (uid:0 nice:0 policy:1 rt_prio:5)
+    -----------------
+
+#                _------=> CPU#
+#               / _-----=> irqs-off
+#              | / _----=> need-resched
+#              || / _---=> hardirq/softirq
+#              ||| / _--=> preempt-depth
+#              |||| /
+#              |||||     delay
+#  cmd     pid ||||| time  |   caller
+#     \   /    |||||   \   |   /
+  <idle>-0     1d.h4    0us+: try_to_wake_up (wake_up_process)
+  <idle>-0     1d..4    4us : schedule (cpu_idle)
+
+
+
+Running this on an idle system, we see that it only took 4 microseconds
+to perform the task switch.  Note, since the trace marker in the
+schedule is before the actual "switch", we stop the tracing when
+the recorded task is about to schedule in. This may change if
+we add a new marker at the end of the scheduler.
+
+Notice that the recorded task is 'sleep' with the PID of 4901 and it
+has an rt_prio of 5. This priority is user-space priority and not
+the internal kernel priority. The policy is 1 for SCHED_FIFO and 2
+for SCHED_RR.
+
+Doing the same with chrt -r 5 and ftrace_enabled set.
+
+# tracer: wakeup
+#
+wakeup latency trace v1.1.5 on 2.6.26-rc8
+--------------------------------------------------------------------
+ latency: 50 us, #60/60, CPU#1 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:2)
+    -----------------
+    | task: sleep-4068 (uid:0 nice:0 policy:2 rt_prio:5)
+    -----------------
+
+#                _------=> CPU#
+#               / _-----=> irqs-off
+#              | / _----=> need-resched
+#              || / _---=> hardirq/softirq
+#              ||| / _--=> preempt-depth
+#              |||| /
+#              |||||     delay
+#  cmd     pid ||||| time  |   caller
+#     \   /    |||||   \   |   /
+ksoftirq-7     1d.H3    0us : try_to_wake_up (wake_up_process)
+ksoftirq-7     1d.H4    1us : sub_preempt_count (marker_probe_cb)
+ksoftirq-7     1d.H3    2us : check_preempt_wakeup (try_to_wake_up)
+ksoftirq-7     1d.H3    3us : update_curr (check_preempt_wakeup)
+ksoftirq-7     1d.H3    4us : calc_delta_mine (update_curr)
+ksoftirq-7     1d.H3    5us : __resched_task (check_preempt_wakeup)
+ksoftirq-7     1d.H3    6us : task_wake_up_rt (try_to_wake_up)
+ksoftirq-7     1d.H3    7us : _spin_unlock_irqrestore (try_to_wake_up)
+[...]
+ksoftirq-7     1d.H2   17us : irq_exit (smp_apic_timer_interrupt)
+ksoftirq-7     1d.H2   18us : sub_preempt_count (irq_exit)
+ksoftirq-7     1d.s3   19us : sub_preempt_count (irq_exit)
+ksoftirq-7     1..s2   20us : rcu_process_callbacks (__do_softirq)
+[...]
+ksoftirq-7     1..s2   26us : __rcu_process_callbacks (rcu_process_callbacks)
+ksoftirq-7     1d.s2   27us : _local_bh_enable (__do_softirq)
+ksoftirq-7     1d.s2   28us : sub_preempt_count (_local_bh_enable)
+ksoftirq-7     1.N.3   29us : sub_preempt_count (ksoftirqd)
+ksoftirq-7     1.N.2   30us : _cond_resched (ksoftirqd)
+ksoftirq-7     1.N.2   31us : __cond_resched (_cond_resched)
+ksoftirq-7     1.N.2   32us : add_preempt_count (__cond_resched)
+ksoftirq-7     1.N.2   33us : schedule (__cond_resched)
+ksoftirq-7     1.N.2   33us : add_preempt_count (schedule)
+ksoftirq-7     1.N.3   34us : hrtick_clear (schedule)
+ksoftirq-7     1dN.3   35us : _spin_lock (schedule)
+ksoftirq-7     1dN.3   36us : add_preempt_count (_spin_lock)
+ksoftirq-7     1d..4   37us : put_prev_task_fair (schedule)
+ksoftirq-7     1d..4   38us : update_curr (put_prev_task_fair)
+[...]
+ksoftirq-7     1d..5   47us : _spin_trylock (tracing_record_cmdline)
+ksoftirq-7     1d..5   48us : add_preempt_count (_spin_trylock)
+ksoftirq-7     1d..6   49us : _spin_unlock (tracing_record_cmdline)
+ksoftirq-7     1d..6   49us : sub_preempt_count (_spin_unlock)
+ksoftirq-7     1d..4   50us : schedule (__cond_resched)
+
+The interrupt went off while running ksoftirqd. This task runs at
+SCHED_OTHER. Why did not we see the 'N' set early? This may be
+a harmless bug with x86_32 and 4K stacks. On x86_32 with 4K stacks
+configured, the interrupt and softirq run with their own stack.
+Some information is held on the top of the task's stack (need_resched
+and preempt_count are both stored there). The setting of the NEED_RESCHED
+bit is done directly to the task's stack, but the reading of the
+NEED_RESCHED is done by looking at the current stack, which in this case
+is the stack for the hard interrupt. This hides the fact that NEED_RESCHED
+has been set. We do not see the 'N' until we switch back to the task's
+assigned stack.
+
+ftrace
+------
+
+ftrace is not only the name of the tracing infrastructure, but it
+is also a name of one of the tracers. The tracer is the function
+tracer. Enabling the function tracer can be done from the
+debug file system. Make sure the ftrace_enabled is set otherwise
+this tracer is a nop.
+
+ # sysctl kernel.ftrace_enabled=1
+ # echo ftrace > /debug/tracing/current_tracer
+ # echo 1 > /debug/tracing/tracing_enabled
+ # usleep 1
+ # echo 0 > /debug/tracing/tracing_enabled
+ # cat /debug/tracing/trace
+# tracer: ftrace
+#
+#           TASK-PID   CPU#    TIMESTAMP  FUNCTION
+#              | |      |          |         |
+            bash-4003  [00]   123.638713: finish_task_switch <-schedule
+            bash-4003  [00]   123.638714: _spin_unlock_irq <-finish_task_switch
+            bash-4003  [00]   123.638714: sub_preempt_count <-_spin_unlock_irq
+            bash-4003  [00]   123.638715: hrtick_set <-schedule
+            bash-4003  [00]   123.638715: _spin_lock_irqsave <-hrtick_set
+            bash-4003  [00]   123.638716: add_preempt_count <-_spin_lock_irqsave
+            bash-4003  [00]   123.638716: _spin_unlock_irqrestore <-hrtick_set
+            bash-4003  [00]   123.638717: sub_preempt_count <-_spin_unlock_irqrestore
+            bash-4003  [00]   123.638717: hrtick_clear <-hrtick_set
+            bash-4003  [00]   123.638718: sub_preempt_count <-schedule
+            bash-4003  [00]   123.638718: sub_preempt_count <-preempt_schedule
+            bash-4003  [00]   123.638719: wait_for_completion <-__stop_machine_run
+            bash-4003  [00]   123.638719: wait_for_common <-wait_for_completion
+            bash-4003  [00]   123.638720: _spin_lock_irq <-wait_for_common
+            bash-4003  [00]   123.638720: add_preempt_count <-_spin_lock_irq
+[...]
+
+
+Note: ftrace uses ring buffers to store the above entries. The newest data
+may overwrite the oldest data. Sometimes using echo to stop the trace
+is not sufficient because the tracing could have overwritten the data
+that you wanted to record. For this reason, it is sometimes better to
+disable tracing directly from a program. This allows you to stop the
+tracing at the point that you hit the part that you are interested in.
+To disable the tracing directly from a C program, something like following
+code snippet can be used:
+
+int trace_fd;
+[...]
+int main(int argc, char *argv[]) {
+	[...]
+	trace_fd = open("/debug/tracing/tracing_enabled", O_WRONLY);
+	[...]
+	if (condition_hit()) {
+		write(trace_fd, "0", 1);
+	}
+	[...]
+}
+
+Note: Here we hard coded the path name. The debugfs mount is not
+guaranteed to be at /debug (and is more commonly at /sys/kernel/debug).
+For simple one time traces, the above is sufficent. For anything else,
+a search through /proc/mounts may be needed to find where the debugfs
+file-system is mounted.
+
+dynamic ftrace
+--------------
+
+If CONFIG_DYNAMIC_FTRACE is set, the system will run with
+virtually no overhead when function tracing is disabled. The way
+this works is the mcount function call (placed at the start of
+every kernel function, produced by the -pg switch in gcc), starts
+of pointing to a simple return. (Enabling FTRACE will include the
+-pg switch in the compiling of the kernel.)
+
+When dynamic ftrace is initialized, it calls kstop_machine to make
+the machine act like a uniprocessor so that it can freely modify code
+without worrying about other processors executing that same code.  At
+initialization, the mcount calls are changed to call a "record_ip"
+function.  After this, the first time a kernel function is called,
+it has the calling address saved in a hash table.
+
+Later on the ftraced kernel thread is awoken and will again call
+kstop_machine if new functions have been recorded. The ftraced thread
+will change all calls to mcount to "nop".  Just calling mcount
+and having mcount return has shown a 10% overhead. By converting
+it to a nop, there is no measurable overhead to the system.
+
+One special side-effect to the recording of the functions being
+traced is that we can now selectively choose which functions we
+wish to trace and which ones we want the mcount calls to remain as
+nops.
+
+Two files are used, one for enabling and one for disabling the tracing
+of specified functions. They are:
+
+  set_ftrace_filter
+
+and
+
+  set_ftrace_notrace
+
+A list of available functions that you can add to these files is listed
+in:
+
+   available_filter_functions
+
+ # cat /debug/tracing/available_filter_functions
+put_prev_task_idle
+kmem_cache_create
+pick_next_task_rt
+get_online_cpus
+pick_next_task_fair
+mutex_lock
+[...]
+
+If I am only interested in sys_nanosleep and hrtimer_interrupt:
+
+ # echo sys_nanosleep hrtimer_interrupt \
+		> /debug/tracing/set_ftrace_filter
+ # echo ftrace > /debug/tracing/current_tracer
+ # echo 1 > /debug/tracing/tracing_enabled
+ # usleep 1
+ # echo 0 > /debug/tracing/tracing_enabled
+ # cat /debug/tracing/trace
+# tracer: ftrace
+#
+#           TASK-PID   CPU#    TIMESTAMP  FUNCTION
+#              | |      |          |         |
+          usleep-4134  [00]  1317.070017: hrtimer_interrupt <-smp_apic_timer_interrupt
+          usleep-4134  [00]  1317.070111: sys_nanosleep <-syscall_call
+          <idle>-0     [00]  1317.070115: hrtimer_interrupt <-smp_apic_timer_interrupt
+
+To see which functions are being traced, you can cat the file:
+
+ # cat /debug/tracing/set_ftrace_filter
+hrtimer_interrupt
+sys_nanosleep
+
+
+Perhaps this is not enough. The filters also allow simple wild cards.
+Only the following are currently available
+
+  <match>*  - will match functions that begin with <match>
+  *<match>  - will match functions that end with <match>
+  *<match>* - will match functions that have <match> in it
+
+These are the only wild cards which are supported.
+
+  <match>*<match> will not work.
+
+ # echo hrtimer_* > /debug/tracing/set_ftrace_filter
+
+Produces:
+
+# tracer: ftrace
+#
+#           TASK-PID   CPU#    TIMESTAMP  FUNCTION
+#              | |      |          |         |
+            bash-4003  [00]  1480.611794: hrtimer_init <-copy_process
+            bash-4003  [00]  1480.611941: hrtimer_start <-hrtick_set
+            bash-4003  [00]  1480.611956: hrtimer_cancel <-hrtick_clear
+            bash-4003  [00]  1480.611956: hrtimer_try_to_cancel <-hrtimer_cancel
+          <idle>-0     [00]  1480.612019: hrtimer_get_next_event <-get_next_timer_interrupt
+          <idle>-0     [00]  1480.612025: hrtimer_get_next_event <-get_next_timer_interrupt
+          <idle>-0     [00]  1480.612032: hrtimer_get_next_event <-get_next_timer_interrupt
+          <idle>-0     [00]  1480.612037: hrtimer_get_next_event <-get_next_timer_interrupt
+          <idle>-0     [00]  1480.612382: hrtimer_get_next_event <-get_next_timer_interrupt
+
+
+Notice that we lost the sys_nanosleep.
+
+ # cat /debug/tracing/set_ftrace_filter
+hrtimer_run_queues
+hrtimer_run_pending
+hrtimer_init
+hrtimer_cancel
+hrtimer_try_to_cancel
+hrtimer_forward
+hrtimer_start
+hrtimer_reprogram
+hrtimer_force_reprogram
+hrtimer_get_next_event
+hrtimer_interrupt
+hrtimer_nanosleep
+hrtimer_wakeup
+hrtimer_get_remaining
+hrtimer_get_res
+hrtimer_init_sleeper
+
+
+This is because the '>' and '>>' act just like they do in bash.
+To rewrite the filters, use '>'
+To append to the filters, use '>>'
+
+To clear out a filter so that all functions will be recorded again:
+
+ # echo > /debug/tracing/set_ftrace_filter
+ # cat /debug/tracing/set_ftrace_filter
+ #
+
+Again, now we want to append.
+
+ # echo sys_nanosleep > /debug/tracing/set_ftrace_filter
+ # cat /debug/tracing/set_ftrace_filter
+sys_nanosleep
+ # echo hrtimer_* >> /debug/tracing/set_ftrace_filter
+ # cat /debug/tracing/set_ftrace_filter
+hrtimer_run_queues
+hrtimer_run_pending
+hrtimer_init
+hrtimer_cancel
+hrtimer_try_to_cancel
+hrtimer_forward
+hrtimer_start
+hrtimer_reprogram
+hrtimer_force_reprogram
+hrtimer_get_next_event
+hrtimer_interrupt
+sys_nanosleep
+hrtimer_nanosleep
+hrtimer_wakeup
+hrtimer_get_remaining
+hrtimer_get_res
+hrtimer_init_sleeper
+
+
+The set_ftrace_notrace prevents those functions from being traced.
+
+ # echo '*preempt*' '*lock*' > /debug/tracing/set_ftrace_notrace
+
+Produces:
+
+# tracer: ftrace
+#
+#           TASK-PID   CPU#    TIMESTAMP  FUNCTION
+#              | |      |          |         |
+            bash-4043  [01]   115.281644: finish_task_switch <-schedule
+            bash-4043  [01]   115.281645: hrtick_set <-schedule
+            bash-4043  [01]   115.281645: hrtick_clear <-hrtick_set
+            bash-4043  [01]   115.281646: wait_for_completion <-__stop_machine_run
+            bash-4043  [01]   115.281647: wait_for_common <-wait_for_completion
+            bash-4043  [01]   115.281647: kthread_stop <-stop_machine_run
+            bash-4043  [01]   115.281648: init_waitqueue_head <-kthread_stop
+            bash-4043  [01]   115.281648: wake_up_process <-kthread_stop
+            bash-4043  [01]   115.281649: try_to_wake_up <-wake_up_process
+
+We can see that there's no more lock or preempt tracing.
+
+ftraced
+-------
+
+As mentioned above, when dynamic ftrace is configured in, a kernel
+thread wakes up once a second and checks to see if there are mcount
+calls that need to be converted into nops. If there are not any, then
+it simply goes back to sleep. But if there are some, it will call
+kstop_machine to convert the calls to nops.
+
+There may be a case in which you do not want this added latency.
+Perhaps you are doing some audio recording and this activity might
+cause skips in the playback. There is an interface to disable
+and enable the "ftraced" kernel thread.
+
+ # echo 0 > /debug/tracing/ftraced_enabled
+
+This will disable the calling of kstop_machine to update the
+mcount calls to nops. Remember that there is a large overhead
+to calling mcount. Without this kernel thread, that overhead will
+exist.
+
+If there are recorded calls to mcount, any write to the ftraced_enabled
+file will cause the kstop_machine to run. This means that a
+user can manually perform the updates when they want to by simply
+echoing a '0' into the ftraced_enabled file.
+
+The updates are also done at the beginning of enabling a tracer
+that uses ftrace function recording.
+
+
+trace_pipe
+----------
+
+The trace_pipe outputs the same content as the trace file, but the effect
+on the tracing is different. Every read from trace_pipe is consumed.
+This means that subsequent reads will be different. The trace
+is live.
+
+ # echo ftrace > /debug/tracing/current_tracer
+ # cat /debug/tracing/trace_pipe > /tmp/trace.out &
+[1] 4153
+ # echo 1 > /debug/tracing/tracing_enabled
+ # usleep 1
+ # echo 0 > /debug/tracing/tracing_enabled
+ # cat /debug/tracing/trace
+# tracer: ftrace
+#
+#           TASK-PID   CPU#    TIMESTAMP  FUNCTION
+#              | |      |          |         |
+
+ #
+ # cat /tmp/trace.out
+            bash-4043  [00] 41.267106: finish_task_switch <-schedule
+            bash-4043  [00] 41.267106: hrtick_set <-schedule
+            bash-4043  [00] 41.267107: hrtick_clear <-hrtick_set
+            bash-4043  [00] 41.267108: wait_for_completion <-__stop_machine_run
+            bash-4043  [00] 41.267108: wait_for_common <-wait_for_completion
+            bash-4043  [00] 41.267109: kthread_stop <-stop_machine_run
+            bash-4043  [00] 41.267109: init_waitqueue_head <-kthread_stop
+            bash-4043  [00] 41.267110: wake_up_process <-kthread_stop
+            bash-4043  [00] 41.267110: try_to_wake_up <-wake_up_process
+            bash-4043  [00] 41.267111: select_task_rq_rt <-try_to_wake_up
+
+
+Note, reading the trace_pipe file will block until more input is added.
+By changing the tracer, trace_pipe will issue an EOF. We needed
+to set the ftrace tracer _before_ cating the trace_pipe file.
+
+
+trace entries
+-------------
+
+Having too much or not enough data can be troublesome in diagnosing
+an issue in the kernel. The file trace_entries is used to modify
+the size of the internal trace buffers. The number listed
+is the number of entries that can be recorded per CPU. To know
+the full size, multiply the number of possible CPUS with the
+number of entries.
+
+ # cat /debug/tracing/trace_entries
+65620
+
+Note, to modify this, you must have tracing completely disabled. To do that,
+echo "none" into the current_tracer. If the current_tracer is not set
+to "none", an EINVAL error will be returned.
+
+ # echo none > /debug/tracing/current_tracer
+ # echo 100000 > /debug/tracing/trace_entries
+ # cat /debug/tracing/trace_entries
+100045
+
+
+Notice that we echoed in 100,000 but the size is 100,045. The entries
+are held in individual pages. It allocates the number of pages it takes
+to fulfill the request. If more entries may fit on the last page
+then they will be added.
+
+ # echo 1 > /debug/tracing/trace_entries
+ # cat /debug/tracing/trace_entries
+85
+
+This shows us that 85 entries can fit in a single page.
+
+The number of pages which will be allocated is limited to a percentage
+of available memory. Allocating too much will produce an error.
+
+ # echo 1000000000000 > /debug/tracing/trace_entries
+-bash: echo: write error: Cannot allocate memory
+ # cat /debug/tracing/trace_entries
+85
+

Documentation/hwmon/ibmaem

@@ -0,0 +1,37 @@
+Kernel driver ibmaem
+======================
+
+Supported systems:
+  * Any recent IBM System X server with Active Energy Manager support.
+    This includes the x3350, x3550, x3650, x3655, x3755, x3850 M2,
+    x3950 M2, and certain HS2x/LS2x/QS2x blades.  The IPMI host interface
+    driver ("ipmi-si") needs to be loaded for this driver to do anything.
+    Prefix: 'ibmaem'
+    Datasheet: Not available
+
+Author: Darrick J. Wong
+
+Description
+-----------
+
+This driver implements sensor reading support for the energy and power
+meters available on various IBM System X hardware through the BMC.  All
+sensor banks will be exported as platform devices; this driver can talk
+to both v1 and v2 interfaces.  This driver is completely separate from the
+older ibmpex driver.
+
+The v1 AEM interface has a simple set of features to monitor energy use.
+There is a register that displays an estimate of raw energy consumption
+since the last BMC reset, and a power sensor that returns average power
+use over a configurable interval.
+
+The v2 AEM interface is a bit more sophisticated, being able to present
+a wider range of energy and power use registers, the power cap as
+set by the AEM software, and temperature sensors.
+
+Special Features
+----------------
+
+The "power_cap" value displays the current system power cap, as set by
+the Active Energy Manager software.  Setting the power cap from the host
+is not currently supported.

Documentation/hwmon/sysfs-interface

@@ -2,17 +2,12 @@ Naming and data format standards for sysfs files
 ------------------------------------------------
 
 The libsensors library offers an interface to the raw sensors data
-through the sysfs interface. See libsensors documentation and source for
-further information. As of writing this document, libsensors
-(from lm_sensors 2.8.3) is heavily chip-dependent. Adding or updating
-support for any given chip requires modifying the library's code.
-This is because libsensors was written for the procfs interface
-older kernel modules were using, which wasn't standardized enough.
-Recent versions of libsensors (from lm_sensors 2.8.2 and later) have
-support for the sysfs interface, though.
-
-The new sysfs interface was designed to be as chip-independent as
-possible.
+through the sysfs interface. Since lm-sensors 3.0.0, libsensors is
+completely chip-independent. It assumes that all the kernel drivers
+implement the standard sysfs interface described in this document.
+This makes adding or updating support for any given chip very easy, as
+libsensors, and applications using it, do not need to be modified.
+This is a major improvement compared to lm-sensors 2.
 
 Note that motherboards vary widely in the connections to sensor chips.
 There is no standard that ensures, for example, that the second
@@ -35,19 +30,17 @@ access this data in a simple and consistent way. That said, such programs
 will have to implement conversion, labeling and hiding of inputs. For
 this reason, it is still not recommended to bypass the library.
 
-If you are developing a userspace application please send us feedback on
-this standard.
-
-Note that this standard isn't completely established yet, so it is subject
-to changes. If you are writing a new hardware monitoring driver those
-features can't seem to fit in this interface, please contact us with your
-extension proposal. Keep in mind that backward compatibility must be
-preserved.
-
 Each chip gets its own directory in the sysfs /sys/devices tree.  To
 find all sensor chips, it is easier to follow the device symlinks from
 /sys/class/hwmon/hwmon*.
 
+Up to lm-sensors 3.0.0, libsensors looks for hardware monitoring attributes
+in the "physical" device directory. Since lm-sensors 3.0.1, attributes found
+in the hwmon "class" device directory are also supported. Complex drivers
+(e.g. drivers for multifunction chips) may want to use this possibility to
+avoid namespace pollution. The only drawback will be that older versions of
+libsensors won't support the driver in question.
+
 All sysfs values are fixed point numbers.
 
 There is only one value per file, unlike the older /proc specification.

Documentation/i2c/busses/i2c-i810

@@ -1,47 +0,0 @@
-Kernel driver i2c-i810
-
-Supported adapters:
-  * Intel 82810, 82810-DC100, 82810E, and 82815 (GMCH)
-  * Intel 82845G (GMCH)
-
-Authors: 
-	Frodo Looijaard <frodol@dds.nl>, 
-	Philip Edelbrock <phil@netroedge.com>,
-        Kyösti Mälkki <kmalkki@cc.hut.fi>,
-	Ralph Metzler <rjkm@thp.uni-koeln.de>,
-	Mark D. Studebaker <mdsxyz123@yahoo.com>
-
-Main contact: Mark Studebaker <mdsxyz123@yahoo.com>
-
-Description 
------------ 
-
-WARNING: If you have an '810' or '815' motherboard, your standard I2C
-temperature sensors are most likely on the 801's I2C bus. You want the
-i2c-i801 driver for those, not this driver.
-
-Now for the i2c-i810...
-
-The GMCH chip contains two I2C interfaces.
-
-The first interface is used for DDC (Data Display Channel) which is a
-serial channel through the VGA monitor connector to a DDC-compliant
-monitor. This interface is defined by the Video Electronics Standards
-Association (VESA). The standards are available for purchase at
-http://www.vesa.org .
-
-The second interface is a general-purpose I2C bus. It may be connected to a
-TV-out chip such as the BT869 or possibly to a digital flat-panel display.
-
-Features
--------- 
-
-Both busses use the i2c-algo-bit driver for 'bit banging'
-and support for specific transactions is provided by i2c-algo-bit.
-
-Issues
-------
-
-If you enable bus testing in i2c-algo-bit (insmod i2c-algo-bit bit_test=1),
-the test may fail; if so, the i2c-i810 driver won't be inserted. However,
-we think this has been fixed.

Documentation/i2c/busses/i2c-prosavage

@@ -1,23 +0,0 @@
-Kernel driver i2c-prosavage
-
-Supported adapters:
-	
-	S3/VIA KM266/VT8375 aka ProSavage8 
-	S3/VIA KM133/VT8365 aka Savage4 
-
-Author: Henk Vergonet <henk@god.dyndns.org>
-
-Description
------------
-
-The Savage4 chips contain two I2C interfaces (aka a I2C 'master' or
-'host'). 
-
-The first interface is used for DDC (Data Display Channel) which is a
-serial channel through the VGA monitor connector to a DDC-compliant
-monitor. This interface is defined by the Video Electronics Standards
-Association (VESA). The standards are available for purchase at
-http://www.vesa.org . The second interface is a general-purpose I2C bus.
-
-Usefull for gaining access to the TV Encoder chips.
-

Documentation/i2c/busses/i2c-savage4

@@ -1,26 +0,0 @@
-Kernel driver i2c-savage4
-
-Supported adapters:
-  * Savage4
-  * Savage2000
-
-Authors: 
-	Alexander Wold <awold@bigfoot.com>,
-	Mark D. Studebaker <mdsxyz123@yahoo.com> 
-
-Description
------------
-
-The Savage4 chips contain two I2C interfaces (aka a I2C 'master'
-or 'host'). 
-
-The first interface is used for DDC (Data Display Channel) which is a
-serial channel through the VGA monitor connector to a DDC-compliant
-monitor. This interface is defined by the Video Electronics Standards
-Association (VESA). The standards are available for purchase at
-http://www.vesa.org . The DDC bus is not yet supported because its register
-is not directly memory-mapped.
-
-The second interface is a general-purpose I2C bus. This is the only
-interface supported by the driver at the moment.
-

Documentation/i2c/chips/max6875

@@ -49,7 +49,7 @@ $ modprobe max6875 force=0,0x50
 
 The MAX6874/MAX6875 ignores address bit 0, so this driver attaches to multiple
 addresses.  For example, for address 0x50, it also reserves 0x51.
-The even-address instance is called 'max6875', the odd one is 'max6875 subclient'.
+The even-address instance is called 'max6875', the odd one is 'dummy'.
 
 
 Programming the chip using i2c-dev

Documentation/i2c/chips/pca9539

@@ -7,7 +7,7 @@ drivers/gpio/pca9539.c instead.
 Supported chips:
   * Philips PCA9539
     Prefix: 'pca9539'
-    Addresses scanned: 0x74 - 0x77
+    Addresses scanned: none
     Datasheet:
         http://www.semiconductors.philips.com/acrobat/datasheets/PCA9539_2.pdf
 
@@ -23,6 +23,14 @@ The input sense can also be inverted.
 The 16 lines are split between two bytes.
 
 
+Detection
+---------
+
+The PCA9539 is difficult to detect and not commonly found in PC machines,
+so you have to pass the I2C bus and address of the installed PCA9539
+devices explicitly to the driver at load time via the force=... parameter.
+
+
 Sysfs entries
 -------------
 

Documentation/i2c/chips/pcf8574

@@ -4,13 +4,13 @@ Kernel driver pcf8574
 Supported chips:
   * Philips PCF8574
     Prefix: 'pcf8574'
-    Addresses scanned: I2C 0x20 - 0x27
+    Addresses scanned: none
     Datasheet: Publicly available at the Philips Semiconductors website
                http://www.semiconductors.philips.com/pip/PCF8574P.html
 
  * Philips PCF8574A
     Prefix: 'pcf8574a'
-    Addresses scanned: I2C 0x38 - 0x3f
+    Addresses scanned: none
     Datasheet: Publicly available at the Philips Semiconductors website
                http://www.semiconductors.philips.com/pip/PCF8574P.html
 
@@ -38,12 +38,10 @@ For more informations see the datasheet.
 Accessing PCF8574(A) via /sys interface
 -------------------------------------
 
-! Be careful !
 The PCF8574(A) is plainly impossible to detect ! Stupid chip.
-So every chip with address in the interval [20..27] and [38..3f] are
-detected as PCF8574(A). If you have other chips in this address
-range, the workaround is to load this module after the one
-for your others chips.
+So, you have to pass the I2C bus and address of the installed PCF857A
+and PCF8574A devices explicitly to the driver at load time via the
+force=... parameter.
 
 On detection (i.e. insmod, modprobe et al.), directories are being
 created for each detected PCF8574(A):

Documentation/i2c/chips/pcf8575

@@ -40,12 +40,9 @@ Detection
 ---------
 
 There is no method known to detect whether a chip on a given I2C address is
-a PCF8575 or whether it is any other I2C device. So there are two alternatives
-to let the driver find the installed PCF8575 devices:
-- Load this driver after any other I2C driver for I2C devices with addresses
-  in the range 0x20 .. 0x27.
-- Pass the I2C bus and address of the installed PCF8575 devices explicitly to
-  the driver at load time via the probe=... or force=... parameters.
+a PCF8575 or whether it is any other I2C device, so you have to pass the I2C
+bus and address of the installed PCF8575 devices explicitly to the driver at
+load time via the force=... parameter.
 
 /sys interface
 --------------

Documentation/i2c/fault-codes

@@ -0,0 +1,127 @@
+This is a summary of the most important conventions for use of fault
+codes in the I2C/SMBus stack.
+
+
+A "Fault" is not always an "Error"
+----------------------------------
+Not all fault reports imply errors; "page faults" should be a familiar
+example.  Software often retries idempotent operations after transient
+faults.  There may be fancier recovery schemes that are appropriate in
+some cases, such as re-initializing (and maybe resetting).  After such
+recovery, triggered by a fault report, there is no error.
+
+In a similar way, sometimes a "fault" code just reports one defined
+result for an operation ... it doesn't indicate that anything is wrong
+at all, just that the outcome wasn't on the "golden path".
+
+In short, your I2C driver code may need to know these codes in order
+to respond correctly.  Other code may need to rely on YOUR code reporting
+the right fault code, so that it can (in turn) behave correctly.
+
+
+I2C and SMBus fault codes
+-------------------------
+These are returned as negative numbers from most calls, with zero or
+some positive number indicating a non-fault return.  The specific
+numbers associated with these symbols differ between architectures,
+though most Linux systems use <asm-generic/errno*.h> numbering.
+
+Note that the descriptions here are not exhaustive.  There are other
+codes that may be returned, and other cases where these codes should
+be returned.  However, drivers should not return other codes for these
+cases (unless the hardware doesn't provide unique fault reports).
+
+Also, codes returned by adapter probe methods follow rules which are
+specific to their host bus (such as PCI, or the platform bus).
+
+
+EAGAIN
+	Returned by I2C adapters when they lose arbitration in master
+	transmit mode:  some other master was transmitting different
+	data at the same time.
+
+	Also returned when trying to invoke an I2C operation in an
+	atomic context, when some task is already using that I2C bus
+	to execute some other operation.
+
+EBADMSG
+	Returned by SMBus logic when an invalid Packet Error Code byte
+	is received.  This code is a CRC covering all bytes in the
+	transaction, and is sent before the terminating STOP.  This
+	fault is only reported on read transactions; the SMBus slave
+	may have a way to report PEC mismatches on writes from the
+	host.  Note that even if PECs are in use, you should not rely
+	on these as the only way to detect incorrect data transfers.
+
+EBUSY
+	Returned by SMBus adapters when the bus was busy for longer
+	than allowed.  This usually indicates some device (maybe the
+	SMBus adapter) needs some fault recovery (such as resetting),
+	or that the reset was attempted but failed.
+
+EINVAL
+	This rather vague error means an invalid parameter has been
+	detected before any I/O operation was started.  Use a more
+	specific fault code when you can.
+
+	One example would be a driver trying an SMBus Block Write
+	with block size outside the range of 1-32 bytes.
+
+EIO
+	This rather vague error means something went wrong when
+	performing an I/O operation.  Use a more specific fault
+	code when you can.
+
+ENODEV
+	Returned by driver probe() methods.  This is a bit more
+	specific than ENXIO, implying the problem isn't with the
+	address, but with the device found there.  Driver probes
+	may verify the device returns *correct* responses, and
+	return this as appropriate.  (The driver core will warn
+	about probe faults other than ENXIO and ENODEV.)
+
+ENOMEM
+	Returned by any component that can't allocate memory when
+	it needs to do so.
+
+ENXIO
+	Returned by I2C adapters to indicate that the address phase
+	of a transfer didn't get an ACK.  While it might just mean
+	an I2C device was temporarily not responding, usually it
+	means there's nothing listening at that address.
+
+	Returned by driver probe() methods to indicate that they
+	found no device to bind to.  (ENODEV may also be used.)
+
+EOPNOTSUPP
+	Returned by an adapter when asked to perform an operation
+	that it doesn't, or can't, support.
+
+	For example, this would be returned when an adapter that
+	doesn't support SMBus block transfers is asked to execute
+	one.  In that case, the driver making that request should
+	have verified that functionality was supported before it
+	made that block transfer request.
+
+	Similarly, if an I2C adapter can't execute all legal I2C
+	messages, it should return this when asked to perform a
+	transaction it can't.  (These limitations can't be seen in
+	the adapter's functionality mask, since the assumption is
+	that if an adapter supports I2C it supports all of I2C.)
+
+EPROTO
+	Returned when slave does not conform to the relevant I2C
+	or SMBus (or chip-specific) protocol specifications.  One
+	case is when the length of an SMBus block data response
+	(from the SMBus slave) is outside the range 1-32 bytes.
+
+ETIMEDOUT
+	This is returned by drivers when an operation took too much
+	time, and was aborted before it completed.
+
+	SMBus adapters may return it when an operation took more
+	time than allowed by the SMBus specification; for example,
+	when a slave stretches clocks too far.  I2C has no such
+	timeouts, but it's normal for I2C adapters to impose some
+	arbitrary limits (much longer than SMBus!) too.
+

Documentation/i2c/smbus-protocol

@@ -42,8 +42,8 @@ Count (8 bits): A data byte containing the length of a block operation.
 [..]: Data sent by I2C device, as opposed to data sent by the host adapter.
 
 
-SMBus Quick Command:  i2c_smbus_write_quick()
-=============================================
+SMBus Quick Command
+===================
 
 This sends a single bit to the device, at the place of the Rd/Wr bit.
 

Documentation/i2c/writing-clients

@@ -25,14 +25,29 @@ routines, and should be zero-initialized except for fields with data you
 provide.  A client structure holds device-specific information like the
 driver model device node, and its I2C address.
 
+/* iff driver uses driver model ("new style") binding model: */
+
+static struct i2c_device_id foo_idtable[] = {
+	{ "foo", my_id_for_foo },
+	{ "bar", my_id_for_bar },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(i2c, foo_idtable);
+
 static struct i2c_driver foo_driver = {
 	.driver = {
 		.name	= "foo",
 	},
 
 	/* iff driver uses driver model ("new style") binding model: */
+	.id_table	= foo_ids,
 	.probe		= foo_probe,
 	.remove		= foo_remove,
+	/* if device autodetection is needed: */
+	.class		= I2C_CLASS_SOMETHING,
+	.detect		= foo_detect,
+	.address_data	= &addr_data,
 
 	/* else, driver uses "legacy" binding model: */
 	.attach_adapter	= foo_attach_adapter,
@@ -173,10 +188,9 @@ handle may be used during foo_probe().  If foo_probe() reports success
 (zero not a negative status code) it may save the handle and use it until
 foo_remove() returns.  That binding model is used by most Linux drivers.
 
-Drivers match devices when i2c_client.driver_name and the driver name are
-the same; this approach is used in several other busses that don't have
-device typing support in the hardware.  The driver and module name should
-match, so hotplug/coldplug mechanisms will modprobe the driver.
+The probe function is called when an entry in the id_table name field
+matches the device's name. It is passed the entry that was matched so
+the driver knows which one in the table matched.
 
 
 Device Creation (Standard driver model)
@@ -207,6 +221,31 @@ in the I2C bus driver. You may want to save the returned i2c_client
 reference for later use.
 
 
+Device Detection (Standard driver model)
+----------------------------------------
+
+Sometimes you do not know in advance which I2C devices are connected to
+a given I2C bus.  This is for example the case of hardware monitoring
+devices on a PC's SMBus.  In that case, you may want to let your driver
+detect supported devices automatically.  This is how the legacy model
+was working, and is now available as an extension to the standard
+driver model (so that we can finally get rid of the legacy model.)
+
+You simply have to define a detect callback which will attempt to
+identify supported devices (returning 0 for supported ones and -ENODEV
+for unsupported ones), a list of addresses to probe, and a device type
+(or class) so that only I2C buses which may have that type of device
+connected (and not otherwise enumerated) will be probed.  The i2c
+core will then call you back as needed and will instantiate a device
+for you for every successful detection.
+
+Note that this mechanism is purely optional and not suitable for all
+devices.  You need some reliable way to identify the supported devices
+(typically using device-specific, dedicated identification registers),
+otherwise misdetections are likely to occur and things can get wrong
+quickly.
+
+
 Device Deletion (Standard driver model)
 ---------------------------------------
 
@@ -559,7 +598,6 @@ SMBus communication
   in terms of it. Never use this function directly!
 
 
-  extern s32 i2c_smbus_write_quick(struct i2c_client * client, u8 value);
   extern s32 i2c_smbus_read_byte(struct i2c_client * client);
   extern s32 i2c_smbus_write_byte(struct i2c_client * client, u8 value);
   extern s32 i2c_smbus_read_byte_data(struct i2c_client * client, u8 command);
@@ -568,30 +606,31 @@ SMBus communication
   extern s32 i2c_smbus_read_word_data(struct i2c_client * client, u8 command);
   extern s32 i2c_smbus_write_word_data(struct i2c_client * client,
                                        u8 command, u16 value);
+  extern s32 i2c_smbus_read_block_data(struct i2c_client * client,
+                                       u8 command, u8 *values);
   extern s32 i2c_smbus_write_block_data(struct i2c_client * client,
                                         u8 command, u8 length,
                                         u8 *values);
   extern s32 i2c_smbus_read_i2c_block_data(struct i2c_client * client,
                                            u8 command, u8 length, u8 *values);
-
-These ones were removed in Linux 2.6.10 because they had no users, but could
-be added back later if needed:
-
-  extern s32 i2c_smbus_read_block_data(struct i2c_client * client,
-                                       u8 command, u8 *values);
   extern s32 i2c_smbus_write_i2c_block_data(struct i2c_client * client,
                                             u8 command, u8 length,
                                             u8 *values);
+
+These ones were removed from i2c-core because they had no users, but could
+be added back later if needed:
+
+  extern s32 i2c_smbus_write_quick(struct i2c_client * client, u8 value);
   extern s32 i2c_smbus_process_call(struct i2c_client * client,
                                     u8 command, u16 value);
   extern s32 i2c_smbus_block_process_call(struct i2c_client *client,
                                           u8 command, u8 length,
                                           u8 *values)
 
-All these transactions return -1 on failure. The 'write' transactions 
-return 0 on success; the 'read' transactions return the read value, except 
-for read_block, which returns the number of values read. The block buffers 
-need not be longer than 32 bytes.
+All these transactions return a negative errno value on failure. The 'write'
+transactions return 0 on success; the 'read' transactions return the read
+value, except for block transactions, which return the number of values
+read. The block buffers need not be longer than 32 bytes.
 
 You can read the file `smbus-protocol' for more information about the
 actual SMBus protocol.

Documentation/i386/boot.txt

@@ -1,887 +0,0 @@
-		     THE LINUX/I386 BOOT PROTOCOL
-		     ----------------------------
-
-		    H. Peter Anvin <hpa@zytor.com>
-			Last update 2007-05-23
-
-On the i386 platform, the Linux kernel uses a rather complicated boot
-convention.  This has evolved partially due to historical aspects, as
-well as the desire in the early days to have the kernel itself be a
-bootable image, the complicated PC memory model and due to changed
-expectations in the PC industry caused by the effective demise of
-real-mode DOS as a mainstream operating system.
-
-Currently, the following versions of the Linux/i386 boot protocol exist.
-
-Old kernels:	zImage/Image support only.  Some very early kernels
-		may not even support a command line.
-
-Protocol 2.00:	(Kernel 1.3.73) Added bzImage and initrd support, as
-		well as a formalized way to communicate between the
-		boot loader and the kernel.  setup.S made relocatable,
-		although the traditional setup area still assumed
-		writable.
-
-Protocol 2.01:	(Kernel 1.3.76) Added a heap overrun warning.
-
-Protocol 2.02:	(Kernel 2.4.0-test3-pre3) New command line protocol.
-		Lower the conventional memory ceiling.	No overwrite
-		of the traditional setup area, thus making booting
-		safe for systems which use the EBDA from SMM or 32-bit
-		BIOS entry points.  zImage deprecated but still
-		supported.
-
-Protocol 2.03:	(Kernel 2.4.18-pre1) Explicitly makes the highest possible
-		initrd address available to the bootloader.
-
-Protocol 2.04:	(Kernel 2.6.14) Extend the syssize field to four bytes.
-
-Protocol 2.05:	(Kernel 2.6.20) Make protected mode kernel relocatable.
-		Introduce relocatable_kernel and kernel_alignment fields.
-
-Protocol 2.06:	(Kernel 2.6.22) Added a field that contains the size of
-		the boot command line.
-
-Protocol 2.07:	(Kernel 2.6.24) Added paravirtualised boot protocol.
-		Introduced hardware_subarch and hardware_subarch_data
-		and KEEP_SEGMENTS flag in load_flags.
-
-Protocol 2.08:	(Kernel 2.6.26) Added crc32 checksum and ELF format
-		payload. Introduced payload_offset and payload length
-		fields to aid in locating the payload.
-
-Protocol 2.09:	(Kernel 2.6.26) Added a field of 64-bit physical
-		pointer to single linked list of struct	setup_data.
-
-**** MEMORY LAYOUT
-
-The traditional memory map for the kernel loader, used for Image or
-zImage kernels, typically looks like:
-
-	|			 |
-0A0000	+------------------------+
-	|  Reserved for BIOS	 |	Do not use.  Reserved for BIOS EBDA.
-09A000	+------------------------+
-	|  Command line		 |
-	|  Stack/heap		 |	For use by the kernel real-mode code.
-098000	+------------------------+	
-	|  Kernel setup		 |	The kernel real-mode code.
-090200	+------------------------+
-	|  Kernel boot sector	 |	The kernel legacy boot sector.
-090000	+------------------------+
-	|  Protected-mode kernel |	The bulk of the kernel image.
-010000	+------------------------+
-	|  Boot loader		 |	<- Boot sector entry point 0000:7C00
-001000	+------------------------+
-	|  Reserved for MBR/BIOS |
-000800	+------------------------+
-	|  Typically used by MBR |
-000600	+------------------------+ 
-	|  BIOS use only	 |
-000000	+------------------------+
-
-
-When using bzImage, the protected-mode kernel was relocated to
-0x100000 ("high memory"), and the kernel real-mode block (boot sector,
-setup, and stack/heap) was made relocatable to any address between
-0x10000 and end of low memory. Unfortunately, in protocols 2.00 and
-2.01 the 0x90000+ memory range is still used internally by the kernel;
-the 2.02 protocol resolves that problem.
-
-It is desirable to keep the "memory ceiling" -- the highest point in
-low memory touched by the boot loader -- as low as possible, since
-some newer BIOSes have begun to allocate some rather large amounts of
-memory, called the Extended BIOS Data Area, near the top of low
-memory.	 The boot loader should use the "INT 12h" BIOS call to verify
-how much low memory is available.
-
-Unfortunately, if INT 12h reports that the amount of memory is too
-low, there is usually nothing the boot loader can do but to report an
-error to the user.  The boot loader should therefore be designed to
-take up as little space in low memory as it reasonably can.  For
-zImage or old bzImage kernels, which need data written into the
-0x90000 segment, the boot loader should make sure not to use memory
-above the 0x9A000 point; too many BIOSes will break above that point.
-
-For a modern bzImage kernel with boot protocol version >= 2.02, a
-memory layout like the following is suggested:
-
-	~                        ~
-        |  Protected-mode kernel |
-100000  +------------------------+
-	|  I/O memory hole	 |
-0A0000	+------------------------+
-	|  Reserved for BIOS	 |	Leave as much as possible unused
-	~                        ~
-	|  Command line		 |	(Can also be below the X+10000 mark)
-X+10000	+------------------------+
-	|  Stack/heap		 |	For use by the kernel real-mode code.
-X+08000	+------------------------+	
-	|  Kernel setup		 |	The kernel real-mode code.
-	|  Kernel boot sector	 |	The kernel legacy boot sector.
-X       +------------------------+
-	|  Boot loader		 |	<- Boot sector entry point 0000:7C00
-001000	+------------------------+
-	|  Reserved for MBR/BIOS |
-000800	+------------------------+
-	|  Typically used by MBR |
-000600	+------------------------+ 
-	|  BIOS use only	 |
-000000	+------------------------+
-
-... where the address X is as low as the design of the boot loader
-permits.
-
-
-**** THE REAL-MODE KERNEL HEADER
-
-In the following text, and anywhere in the kernel boot sequence, "a
-sector" refers to 512 bytes.  It is independent of the actual sector
-size of the underlying medium.
-
-The first step in loading a Linux kernel should be to load the
-real-mode code (boot sector and setup code) and then examine the
-following header at offset 0x01f1.  The real-mode code can total up to
-32K, although the boot loader may choose to load only the first two
-sectors (1K) and then examine the bootup sector size.
-
-The header looks like:
-
-Offset	Proto	Name		Meaning
-/Size
-
-01F1/1	ALL(1	setup_sects	The size of the setup in sectors
-01F2/2	ALL	root_flags	If set, the root is mounted readonly
-01F4/4	2.04+(2	syssize		The size of the 32-bit code in 16-byte paras
-01F8/2	ALL	ram_size	DO NOT USE - for bootsect.S use only
-01FA/2	ALL	vid_mode	Video mode control
-01FC/2	ALL	root_dev	Default root device number
-01FE/2	ALL	boot_flag	0xAA55 magic number
-0200/2	2.00+	jump		Jump instruction
-0202/4	2.00+	header		Magic signature "HdrS"
-0206/2	2.00+	version		Boot protocol version supported
-0208/4	2.00+	realmode_swtch	Boot loader hook (see below)
-020C/2	2.00+	start_sys	The load-low segment (0x1000) (obsolete)
-020E/2	2.00+	kernel_version	Pointer to kernel version string
-0210/1	2.00+	type_of_loader	Boot loader identifier
-0211/1	2.00+	loadflags	Boot protocol option flags
-0212/2	2.00+	setup_move_size	Move to high memory size (used with hooks)
-0214/4	2.00+	code32_start	Boot loader hook (see below)
-0218/4	2.00+	ramdisk_image	initrd load address (set by boot loader)
-021C/4	2.00+	ramdisk_size	initrd size (set by boot loader)
-0220/4	2.00+	bootsect_kludge	DO NOT USE - for bootsect.S use only
-0224/2	2.01+	heap_end_ptr	Free memory after setup end
-0226/2	N/A	pad1		Unused
-0228/4	2.02+	cmd_line_ptr	32-bit pointer to the kernel command line
-022C/4	2.03+	initrd_addr_max	Highest legal initrd address
-0230/4	2.05+	kernel_alignment Physical addr alignment required for kernel
-0234/1	2.05+	relocatable_kernel Whether kernel is relocatable or not
-0235/3	N/A	pad2		Unused
-0238/4	2.06+	cmdline_size	Maximum size of the kernel command line
-023C/4	2.07+	hardware_subarch Hardware subarchitecture
-0240/8	2.07+	hardware_subarch_data Subarchitecture-specific data
-0248/4	2.08+	payload_offset	Offset of kernel payload
-024C/4	2.08+	payload_length	Length of kernel payload
-0250/8	2.09+	setup_data	64-bit physical pointer to linked list
-				of struct setup_data
-
-(1) For backwards compatibility, if the setup_sects field contains 0, the
-    real value is 4.
-
-(2) For boot protocol prior to 2.04, the upper two bytes of the syssize
-    field are unusable, which means the size of a bzImage kernel
-    cannot be determined.
-
-If the "HdrS" (0x53726448) magic number is not found at offset 0x202,
-the boot protocol version is "old".  Loading an old kernel, the
-following parameters should be assumed:
-
-	Image type = zImage
-	initrd not supported
-	Real-mode kernel must be located at 0x90000.
-
-Otherwise, the "version" field contains the protocol version,
-e.g. protocol version 2.01 will contain 0x0201 in this field.  When
-setting fields in the header, you must make sure only to set fields
-supported by the protocol version in use.
-
-
-**** DETAILS OF HEADER FIELDS
-
-For each field, some are information from the kernel to the bootloader
-("read"), some are expected to be filled out by the bootloader
-("write"), and some are expected to be read and modified by the
-bootloader ("modify").
-
-All general purpose boot loaders should write the fields marked
-(obligatory).  Boot loaders who want to load the kernel at a
-nonstandard address should fill in the fields marked (reloc); other
-boot loaders can ignore those fields.
-
-The byte order of all fields is littleendian (this is x86, after all.)
-
-Field name:	setup_sects
-Type:		read
-Offset/size:	0x1f1/1
-Protocol:	ALL
-
-  The size of the setup code in 512-byte sectors.  If this field is
-  0, the real value is 4.  The real-mode code consists of the boot
-  sector (always one 512-byte sector) plus the setup code.
-
-Field name:	 root_flags
-Type:		 modify (optional)
-Offset/size:	 0x1f2/2
-Protocol:	 ALL
-
-  If this field is nonzero, the root defaults to readonly.  The use of
-  this field is deprecated; use the "ro" or "rw" options on the
-  command line instead.
-
-Field name:	syssize
-Type:		read
-Offset/size:	0x1f4/4 (protocol 2.04+) 0x1f4/2 (protocol ALL)
-Protocol:	2.04+
-
-  The size of the protected-mode code in units of 16-byte paragraphs.
-  For protocol versions older than 2.04 this field is only two bytes
-  wide, and therefore cannot be trusted for the size of a kernel if
-  the LOAD_HIGH flag is set.
-
-Field name:	ram_size
-Type:		kernel internal
-Offset/size:	0x1f8/2
-Protocol:	ALL
-
-  This field is obsolete.
-
-Field name:	vid_mode
-Type:		modify (obligatory)
-Offset/size:	0x1fa/2
-
-  Please see the section on SPECIAL COMMAND LINE OPTIONS.
-
-Field name:	root_dev
-Type:		modify (optional)
-Offset/size:	0x1fc/2
-Protocol:	ALL
-
-  The default root device device number.  The use of this field is
-  deprecated, use the "root=" option on the command line instead.
-
-Field name:	boot_flag
-Type:		read
-Offset/size:	0x1fe/2
-Protocol:	ALL
-
-  Contains 0xAA55.  This is the closest thing old Linux kernels have
-  to a magic number.
-
-Field name:	jump
-Type:		read
-Offset/size:	0x200/2
-Protocol:	2.00+
-
-  Contains an x86 jump instruction, 0xEB followed by a signed offset
-  relative to byte 0x202.  This can be used to determine the size of
-  the header.
-
-Field name:	header
-Type:		read
-Offset/size:	0x202/4
-Protocol:	2.00+
-
-  Contains the magic number "HdrS" (0x53726448).
-
-Field name:	version
-Type:		read
-Offset/size:	0x206/2
-Protocol:	2.00+
-
-  Contains the boot protocol version, in (major << 8)+minor format,
-  e.g. 0x0204 for version 2.04, and 0x0a11 for a hypothetical version
-  10.17.
-
-Field name:	readmode_swtch
-Type:		modify (optional)
-Offset/size:	0x208/4
-Protocol:	2.00+
-
-  Boot loader hook (see ADVANCED BOOT LOADER HOOKS below.)
-
-Field name:	start_sys
-Type:		read
-Offset/size:	0x20c/4
-Protocol:	2.00+
-
-  The load low segment (0x1000).  Obsolete.
-
-Field name:	kernel_version
-Type:		read
-Offset/size:	0x20e/2
-Protocol:	2.00+
-
-  If set to a nonzero value, contains a pointer to a NUL-terminated
-  human-readable kernel version number string, less 0x200.  This can
-  be used to display the kernel version to the user.  This value
-  should be less than (0x200*setup_sects).
-
-  For example, if this value is set to 0x1c00, the kernel version
-  number string can be found at offset 0x1e00 in the kernel file.
-  This is a valid value if and only if the "setup_sects" field
-  contains the value 15 or higher, as:
-
-	0x1c00  < 15*0x200 (= 0x1e00) but
-	0x1c00 >= 14*0x200 (= 0x1c00)
-
-	0x1c00 >> 9 = 14, so the minimum value for setup_secs is 15.
-
-Field name:	type_of_loader
-Type:		write (obligatory)
-Offset/size:	0x210/1
-Protocol:	2.00+
-
-  If your boot loader has an assigned id (see table below), enter
-  0xTV here, where T is an identifier for the boot loader and V is
-  a version number.  Otherwise, enter 0xFF here.
-
-  Assigned boot loader ids:
-	0  LILO			(0x00 reserved for pre-2.00 bootloader)
-	1  Loadlin
-	2  bootsect-loader	(0x20, all other values reserved)
-	3  SYSLINUX
-	4  EtherBoot
-	5  ELILO
-	7  GRuB
-	8  U-BOOT
-	9  Xen
-	A  Gujin
-	B  Qemu
-
-  Please contact <hpa@zytor.com> if you need a bootloader ID
-  value assigned.
-
-Field name:	loadflags
-Type:		modify (obligatory)
-Offset/size:	0x211/1
-Protocol:	2.00+
-
-  This field is a bitmask.
-
-  Bit 0 (read):	LOADED_HIGH
-	- If 0, the protected-mode code is loaded at 0x10000.
-	- If 1, the protected-mode code is loaded at 0x100000.
-
-  Bit 6 (write): KEEP_SEGMENTS
-	Protocol: 2.07+
-	- if 0, reload the segment registers in the 32bit entry point.
-	- if 1, do not reload the segment registers in the 32bit entry point.
-		Assume that %cs %ds %ss %es are all set to flat segments with
-		a base of 0 (or the equivalent for their environment).
-
-  Bit 7 (write): CAN_USE_HEAP
-	Set this bit to 1 to indicate that the value entered in the
-	heap_end_ptr is valid.  If this field is clear, some setup code
-	functionality will be disabled.
-
-Field name:	setup_move_size
-Type:		modify (obligatory)
-Offset/size:	0x212/2
-Protocol:	2.00-2.01
-
-  When using protocol 2.00 or 2.01, if the real mode kernel is not
-  loaded at 0x90000, it gets moved there later in the loading
-  sequence.  Fill in this field if you want additional data (such as
-  the kernel command line) moved in addition to the real-mode kernel
-  itself.
-
-  The unit is bytes starting with the beginning of the boot sector.
-  
-  This field is can be ignored when the protocol is 2.02 or higher, or
-  if the real-mode code is loaded at 0x90000.
-
-Field name:	code32_start
-Type:		modify (optional, reloc)
-Offset/size:	0x214/4
-Protocol:	2.00+
-
-  The address to jump to in protected mode.  This defaults to the load
-  address of the kernel, and can be used by the boot loader to
-  determine the proper load address.
-
-  This field can be modified for two purposes:
-
-  1. as a boot loader hook (see ADVANCED BOOT LOADER HOOKS below.)
-
-  2. if a bootloader which does not install a hook loads a
-     relocatable kernel at a nonstandard address it will have to modify
-     this field to point to the load address.
-
-Field name:	ramdisk_image
-Type:		write (obligatory)
-Offset/size:	0x218/4
-Protocol:	2.00+
-
-  The 32-bit linear address of the initial ramdisk or ramfs.  Leave at
-  zero if there is no initial ramdisk/ramfs.
-
-Field name:	ramdisk_size
-Type:		write (obligatory)
-Offset/size:	0x21c/4
-Protocol:	2.00+
-
-  Size of the initial ramdisk or ramfs.  Leave at zero if there is no
-  initial ramdisk/ramfs.
-
-Field name:	bootsect_kludge
-Type:		kernel internal
-Offset/size:	0x220/4
-Protocol:	2.00+
-
-  This field is obsolete.
-
-Field name:	heap_end_ptr
-Type:		write (obligatory)
-Offset/size:	0x224/2
-Protocol:	2.01+
-
-  Set this field to the offset (from the beginning of the real-mode
-  code) of the end of the setup stack/heap, minus 0x0200.
-
-Field name:	cmd_line_ptr
-Type:		write (obligatory)
-Offset/size:	0x228/4
-Protocol:	2.02+
-
-  Set this field to the linear address of the kernel command line.
-  The kernel command line can be located anywhere between the end of
-  the setup heap and 0xA0000; it does not have to be located in the
-  same 64K segment as the real-mode code itself.
-
-  Fill in this field even if your boot loader does not support a
-  command line, in which case you can point this to an empty string
-  (or better yet, to the string "auto".)  If this field is left at
-  zero, the kernel will assume that your boot loader does not support
-  the 2.02+ protocol.
-
-Field name:	initrd_addr_max
-Type:		read
-Offset/size:	0x22c/4
-Protocol:	2.03+
-
-  The maximum address that may be occupied by the initial
-  ramdisk/ramfs contents.  For boot protocols 2.02 or earlier, this
-  field is not present, and the maximum address is 0x37FFFFFF.  (This
-  address is defined as the address of the highest safe byte, so if
-  your ramdisk is exactly 131072 bytes long and this field is
-  0x37FFFFFF, you can start your ramdisk at 0x37FE0000.)
-
-Field name:	kernel_alignment
-Type:		read (reloc)
-Offset/size:	0x230/4
-Protocol:	2.05+
-
-  Alignment unit required by the kernel (if relocatable_kernel is true.)
-
-Field name:	relocatable_kernel
-Type:		read (reloc)
-Offset/size:	0x234/1
-Protocol:	2.05+
-
-  If this field is nonzero, the protected-mode part of the kernel can
-  be loaded at any address that satisfies the kernel_alignment field.
-  After loading, the boot loader must set the code32_start field to
-  point to the loaded code, or to a boot loader hook.
-
-Field name:	cmdline_size
-Type:		read
-Offset/size:	0x238/4
-Protocol:	2.06+
-
-  The maximum size of the command line without the terminating
-  zero. This means that the command line can contain at most
-  cmdline_size characters. With protocol version 2.05 and earlier, the
-  maximum size was 255.
-
-Field name:	hardware_subarch
-Type:		write
-Offset/size:	0x23c/4
-Protocol:	2.07+
-
-  In a paravirtualized environment the hardware low level architectural
-  pieces such as interrupt handling, page table handling, and
-  accessing process control registers needs to be done differently.
-
-  This field allows the bootloader to inform the kernel we are in one
-  one of those environments.
-
-  0x00000000	The default x86/PC environment
-  0x00000001	lguest
-  0x00000002	Xen
-
-Field name:	hardware_subarch_data
-Type:		write
-Offset/size:	0x240/8
-Protocol:	2.07+
-
-  A pointer to data that is specific to hardware subarch
-
-Field name:	payload_offset
-Type:		read
-Offset/size:	0x248/4
-Protocol:	2.08+
-
-  If non-zero then this field contains the offset from the end of the
-  real-mode code to the payload.
-
-  The payload may be compressed. The format of both the compressed and
-  uncompressed data should be determined using the standard magic
-  numbers. Currently only gzip compressed ELF is used.
-  
-Field name:	payload_length
-Type:		read
-Offset/size:	0x24c/4
-Protocol:	2.08+
-
-  The length of the payload.
-
-**** THE IMAGE CHECKSUM
-
-From boot protocol version 2.08 onwards the CRC-32 is calculated over
-the entire file using the characteristic polynomial 0x04C11DB7 and an
-initial remainder of 0xffffffff.  The checksum is appended to the
-file; therefore the CRC of the file up to the limit specified in the
-syssize field of the header is always 0.
-
-**** THE KERNEL COMMAND LINE
-
-The kernel command line has become an important way for the boot
-loader to communicate with the kernel.  Some of its options are also
-relevant to the boot loader itself, see "special command line options"
-below.
-
-The kernel command line is a null-terminated string. The maximum
-length can be retrieved from the field cmdline_size.  Before protocol
-version 2.06, the maximum was 255 characters.  A string that is too
-long will be automatically truncated by the kernel.
-
-If the boot protocol version is 2.02 or later, the address of the
-kernel command line is given by the header field cmd_line_ptr (see
-above.)  This address can be anywhere between the end of the setup
-heap and 0xA0000.
-
-If the protocol version is *not* 2.02 or higher, the kernel
-command line is entered using the following protocol:
-
-	At offset 0x0020 (word), "cmd_line_magic", enter the magic
-	number 0xA33F.
-
-	At offset 0x0022 (word), "cmd_line_offset", enter the offset
-	of the kernel command line (relative to the start of the
-	real-mode kernel).
-	
-	The kernel command line *must* be within the memory region
-	covered by setup_move_size, so you may need to adjust this
-	field.
-
-Field name:	setup_data
-Type:		write (obligatory)
-Offset/size:	0x250/8
-Protocol:	2.09+
-
-  The 64-bit physical pointer to NULL terminated single linked list of
-  struct setup_data. This is used to define a more extensible boot
-  parameters passing mechanism. The definition of struct setup_data is
-  as follow:
-
-  struct setup_data {
-	  u64 next;
-	  u32 type;
-	  u32 len;
-	  u8  data[0];
-  };
-
-  Where, the next is a 64-bit physical pointer to the next node of
-  linked list, the next field of the last node is 0; the type is used
-  to identify the contents of data; the len is the length of data
-  field; the data holds the real payload.
-
-
-**** MEMORY LAYOUT OF THE REAL-MODE CODE
-
-The real-mode code requires a stack/heap to be set up, as well as
-memory allocated for the kernel command line.  This needs to be done
-in the real-mode accessible memory in bottom megabyte.
-
-It should be noted that modern machines often have a sizable Extended
-BIOS Data Area (EBDA).  As a result, it is advisable to use as little
-of the low megabyte as possible.
-
-Unfortunately, under the following circumstances the 0x90000 memory
-segment has to be used:
-
-	- When loading a zImage kernel ((loadflags & 0x01) == 0).
-	- When loading a 2.01 or earlier boot protocol kernel.
-
-	  -> For the 2.00 and 2.01 boot protocols, the real-mode code
-	     can be loaded at another address, but it is internally
-	     relocated to 0x90000.  For the "old" protocol, the
-	     real-mode code must be loaded at 0x90000.
-
-When loading at 0x90000, avoid using memory above 0x9a000.
-
-For boot protocol 2.02 or higher, the command line does not have to be
-located in the same 64K segment as the real-mode setup code; it is
-thus permitted to give the stack/heap the full 64K segment and locate
-the command line above it.
-
-The kernel command line should not be located below the real-mode
-code, nor should it be located in high memory.
-
-
-**** SAMPLE BOOT CONFIGURATION
-
-As a sample configuration, assume the following layout of the real
-mode segment:
-
-    When loading below 0x90000, use the entire segment:
-
-	0x0000-0x7fff	Real mode kernel
-	0x8000-0xdfff	Stack and heap
-	0xe000-0xffff	Kernel command line
-
-    When loading at 0x90000 OR the protocol version is 2.01 or earlier:
-
-	0x0000-0x7fff	Real mode kernel
-	0x8000-0x97ff	Stack and heap
-	0x9800-0x9fff	Kernel command line
-
-Such a boot loader should enter the following fields in the header:
-
-	unsigned long base_ptr;	/* base address for real-mode segment */
-
-	if ( setup_sects == 0 ) {
-		setup_sects = 4;
-	}
-
-	if ( protocol >= 0x0200 ) {
-		type_of_loader = <type code>;
-		if ( loading_initrd ) {
-			ramdisk_image = <initrd_address>;
-			ramdisk_size = <initrd_size>;
-		}
-
-		if ( protocol >= 0x0202 && loadflags & 0x01 )
-			heap_end = 0xe000;
-		else
-			heap_end = 0x9800;
-
-		if ( protocol >= 0x0201 ) {
-			heap_end_ptr = heap_end - 0x200;
-			loadflags |= 0x80; /* CAN_USE_HEAP */
-		}
-
-		if ( protocol >= 0x0202 ) {
-			cmd_line_ptr = base_ptr + heap_end;
-			strcpy(cmd_line_ptr, cmdline);
-		} else {
-			cmd_line_magic	= 0xA33F;
-			cmd_line_offset = heap_end;
-			setup_move_size = heap_end + strlen(cmdline)+1;
-			strcpy(base_ptr+cmd_line_offset, cmdline);
-		}
-	} else {
-		/* Very old kernel */
-
-		heap_end = 0x9800;
-
-		cmd_line_magic	= 0xA33F;
-		cmd_line_offset = heap_end;
-
-		/* A very old kernel MUST have its real-mode code
-		   loaded at 0x90000 */
-
-		if ( base_ptr != 0x90000 ) {
-			/* Copy the real-mode kernel */
-			memcpy(0x90000, base_ptr, (setup_sects+1)*512);
-			base_ptr = 0x90000;		 /* Relocated */
-		}
-
-		strcpy(0x90000+cmd_line_offset, cmdline);
-
-		/* It is recommended to clear memory up to the 32K mark */
-		memset(0x90000 + (setup_sects+1)*512, 0,
-		       (64-(setup_sects+1))*512);
-	}
-
-
-**** LOADING THE REST OF THE KERNEL
-
-The 32-bit (non-real-mode) kernel starts at offset (setup_sects+1)*512
-in the kernel file (again, if setup_sects == 0 the real value is 4.)
-It should be loaded at address 0x10000 for Image/zImage kernels and
-0x100000 for bzImage kernels.
-
-The kernel is a bzImage kernel if the protocol >= 2.00 and the 0x01
-bit (LOAD_HIGH) in the loadflags field is set:
-
-	is_bzImage = (protocol >= 0x0200) && (loadflags & 0x01);
-	load_address = is_bzImage ? 0x100000 : 0x10000;
-
-Note that Image/zImage kernels can be up to 512K in size, and thus use
-the entire 0x10000-0x90000 range of memory.  This means it is pretty
-much a requirement for these kernels to load the real-mode part at
-0x90000.  bzImage kernels allow much more flexibility.
-
-
-**** SPECIAL COMMAND LINE OPTIONS
-
-If the command line provided by the boot loader is entered by the
-user, the user may expect the following command line options to work.
-They should normally not be deleted from the kernel command line even
-though not all of them are actually meaningful to the kernel.  Boot
-loader authors who need additional command line options for the boot
-loader itself should get them registered in
-Documentation/kernel-parameters.txt to make sure they will not
-conflict with actual kernel options now or in the future.
-
-  vga=<mode>
-	<mode> here is either an integer (in C notation, either
-	decimal, octal, or hexadecimal) or one of the strings
-	"normal" (meaning 0xFFFF), "ext" (meaning 0xFFFE) or "ask"
-	(meaning 0xFFFD).  This value should be entered into the
-	vid_mode field, as it is used by the kernel before the command
-	line is parsed.
-
-  mem=<size>
-	<size> is an integer in C notation optionally followed by
-	(case insensitive) K, M, G, T, P or E (meaning << 10, << 20,
-	<< 30, << 40, << 50 or << 60).  This specifies the end of
-	memory to the kernel. This affects the possible placement of
-	an initrd, since an initrd should be placed near end of
-	memory.  Note that this is an option to *both* the kernel and
-	the bootloader!
-
-  initrd=<file>
-	An initrd should be loaded.  The meaning of <file> is
-	obviously bootloader-dependent, and some boot loaders
-	(e.g. LILO) do not have such a command.
-
-In addition, some boot loaders add the following options to the
-user-specified command line:
-
-  BOOT_IMAGE=<file>
-	The boot image which was loaded.  Again, the meaning of <file>
-	is obviously bootloader-dependent.
-
-  auto
-	The kernel was booted without explicit user intervention.
-
-If these options are added by the boot loader, it is highly
-recommended that they are located *first*, before the user-specified
-or configuration-specified command line.  Otherwise, "init=/bin/sh"
-gets confused by the "auto" option.
-
-
-**** RUNNING THE KERNEL
-
-The kernel is started by jumping to the kernel entry point, which is
-located at *segment* offset 0x20 from the start of the real mode
-kernel.  This means that if you loaded your real-mode kernel code at
-0x90000, the kernel entry point is 9020:0000.
-
-At entry, ds = es = ss should point to the start of the real-mode
-kernel code (0x9000 if the code is loaded at 0x90000), sp should be
-set up properly, normally pointing to the top of the heap, and
-interrupts should be disabled.  Furthermore, to guard against bugs in
-the kernel, it is recommended that the boot loader sets fs = gs = ds =
-es = ss.
-
-In our example from above, we would do:
-
-	/* Note: in the case of the "old" kernel protocol, base_ptr must
-	   be == 0x90000 at this point; see the previous sample code */
-
-	seg = base_ptr >> 4;
-
-	cli();	/* Enter with interrupts disabled! */
-
-	/* Set up the real-mode kernel stack */
-	_SS = seg;
-	_SP = heap_end;
-
-	_DS = _ES = _FS = _GS = seg;
-	jmp_far(seg+0x20, 0);	/* Run the kernel */
-
-If your boot sector accesses a floppy drive, it is recommended to
-switch off the floppy motor before running the kernel, since the
-kernel boot leaves interrupts off and thus the motor will not be
-switched off, especially if the loaded kernel has the floppy driver as
-a demand-loaded module!
-
-
-**** ADVANCED BOOT LOADER HOOKS
-
-If the boot loader runs in a particularly hostile environment (such as
-LOADLIN, which runs under DOS) it may be impossible to follow the
-standard memory location requirements.  Such a boot loader may use the
-following hooks that, if set, are invoked by the kernel at the
-appropriate time.  The use of these hooks should probably be
-considered an absolutely last resort!
-
-IMPORTANT: All the hooks are required to preserve %esp, %ebp, %esi and
-%edi across invocation.
-
-  realmode_swtch:
-	A 16-bit real mode far subroutine invoked immediately before
-	entering protected mode.  The default routine disables NMI, so
-	your routine should probably do so, too.
-
-  code32_start:
-	A 32-bit flat-mode routine *jumped* to immediately after the
-	transition to protected mode, but before the kernel is
-	uncompressed.  No segments, except CS, are guaranteed to be
-	set up (current kernels do, but older ones do not); you should
-	set them up to BOOT_DS (0x18) yourself.
-
-	After completing your hook, you should jump to the address
-	that was in this field before your boot loader overwrote it
-	(relocated, if appropriate.)
-
-
-**** 32-bit BOOT PROTOCOL
-
-For machine with some new BIOS other than legacy BIOS, such as EFI,
-LinuxBIOS, etc, and kexec, the 16-bit real mode setup code in kernel
-based on legacy BIOS can not be used, so a 32-bit boot protocol needs
-to be defined.
-
-In 32-bit boot protocol, the first step in loading a Linux kernel
-should be to setup the boot parameters (struct boot_params,
-traditionally known as "zero page"). The memory for struct boot_params
-should be allocated and initialized to all zero. Then the setup header
-from offset 0x01f1 of kernel image on should be loaded into struct
-boot_params and examined. The end of setup header can be calculated as
-follow:
-
-	0x0202 + byte value at offset 0x0201
-
-In addition to read/modify/write the setup header of the struct
-boot_params as that of 16-bit boot protocol, the boot loader should
-also fill the additional fields of the struct boot_params as that
-described in zero-page.txt.
-
-After setupping the struct boot_params, the boot loader can load the
-32/64-bit kernel in the same way as that of 16-bit boot protocol.
-
-In 32-bit boot protocol, the kernel is started by jumping to the
-32-bit kernel entry point, which is the start address of loaded
-32/64-bit kernel.
-
-At entry, the CPU must be in 32-bit protected mode with paging
-disabled; a GDT must be loaded with the descriptors for selectors
-__BOOT_CS(0x10) and __BOOT_DS(0x18); both descriptors must be 4G flat
-segment; __BOOS_CS must have execute/read permission, and __BOOT_DS
-must have read/write permission; CS must be __BOOT_CS and DS, ES, SS
-must be __BOOT_DS; interrupt must be disabled; %esi must hold the base
-address of the struct boot_params; %ebp, %edi and %ebx must be zero.

Documentation/ioctl-number.txt

@@ -117,6 +117,7 @@ Code	Seq#	Include File		Comments
 					<mailto:natalia@nikhefk.nikhef.nl>
 'c'	00-7F	linux/comstats.h	conflict!
 'c'	00-7F	linux/coda.h		conflict!
+'c'	80-9F	asm-s390/chsc.h
 'd'	00-FF	linux/char/drm/drm/h	conflict!
 'd'	00-DF	linux/video_decoder.h	conflict!
 'd'	F0-FF	linux/digi1.h

Documentation/ioctl/hdio.txt

@@ -508,12 +508,13 @@ HDIO_DRIVE_RESET		execute a device reset
 
 	error returns:
 	  EACCES	Access denied:  requires CAP_SYS_ADMIN
+	  ENXIO		No such device:	phy dead or ctl_addr == 0
+	  EIO		I/O error:	reset timed out or hardware error
 
 	notes:
 
-	  Abort any current command, prevent anything else from being
-	  queued, execute a reset on the device, and issue BLKRRPART
-	  ioctl on the block device.
+	  Execute a reset on the device as soon as the current IO
+	  operation has completed.
 
 	  Executes an ATAPI soft reset if applicable, otherwise
 	  executes an ATA soft reset on the controller.

Documentation/kdump/kdump.txt

@@ -109,7 +109,7 @@ There are two possible methods of using Kdump.
 2) Or use the system kernel binary itself as dump-capture kernel and there is
    no need to build a separate dump-capture kernel. This is possible
    only with the architecutres which support a relocatable kernel. As
-   of today i386 and ia64 architectures support relocatable kernel.
+   of today, i386, x86_64 and ia64 architectures support relocatable kernel.
 
 Building a relocatable kernel is advantageous from the point of view that
 one does not have to build a second kernel for capturing the dump. But

Documentation/kernel-doc-nano-HOWTO.txt

@@ -1,6 +1,105 @@
 kernel-doc nano-HOWTO
 =====================
 
+How to format kernel-doc comments
+---------------------------------
+
+In order to provide embedded, 'C' friendly, easy to maintain,
+but consistent and extractable documentation of the functions and
+data structures in the Linux kernel, the Linux kernel has adopted
+a consistent style for documenting functions and their parameters,
+and structures and their members.
+
+The format for this documentation is called the kernel-doc format.
+It is documented in this Documentation/kernel-doc-nano-HOWTO.txt file.
+
+This style embeds the documentation within the source files, using
+a few simple conventions.  The scripts/kernel-doc perl script, some
+SGML templates in Documentation/DocBook, and other tools understand
+these conventions, and are used to extract this embedded documentation
+into various documents.
+
+In order to provide good documentation of kernel functions and data
+structures, please use the following conventions to format your
+kernel-doc comments in Linux kernel source.
+
+We definitely need kernel-doc formatted documentation for functions
+that are exported to loadable modules using EXPORT_SYMBOL.
+
+We also look to provide kernel-doc formatted documentation for
+functions externally visible to other kernel files (not marked
+"static").
+
+We also recommend providing kernel-doc formatted documentation
+for private (file "static") routines, for consistency of kernel
+source code layout.  But this is lower priority and at the
+discretion of the MAINTAINER of that kernel source file.
+
+Data structures visible in kernel include files should also be
+documented using kernel-doc formatted comments.
+
+The opening comment mark "/**" is reserved for kernel-doc comments.
+Only comments so marked will be considered by the kernel-doc scripts,
+and any comment so marked must be in kernel-doc format.  Do not use
+"/**" to be begin a comment block unless the comment block contains
+kernel-doc formatted comments.  The closing comment marker for
+kernel-doc comments can be either "*/" or "**/".
+
+Kernel-doc comments should be placed just before the function
+or data structure being described.
+
+Example kernel-doc function comment:
+
+/**
+ * foobar() - short function description of foobar
+ * @arg1:	Describe the first argument to foobar.
+ * @arg2:	Describe the second argument to foobar.
+ *		One can provide multiple line descriptions
+ *		for arguments.
+ *
+ * A longer description, with more discussion of the function foobar()
+ * that might be useful to those using or modifying it.  Begins with
+ * empty comment line, and may include additional embedded empty
+ * comment lines.
+ *
+ * The longer description can have multiple paragraphs.
+ **/
+
+The first line, with the short description, must be on a single line.
+
+The @argument descriptions must begin on the very next line following
+this opening short function description line, with no intervening
+empty comment lines.
+
+Example kernel-doc data structure comment.
+
+/**
+ * struct blah - the basic blah structure
+ * @mem1:	describe the first member of struct blah
+ * @mem2:	describe the second member of struct blah,
+ *		perhaps with more lines and words.
+ *
+ * Longer description of this structure.
+ **/
+
+The kernel-doc function comments describe each parameter to the
+function, in order, with the @name lines.
+
+The kernel-doc data structure comments describe each structure member
+in the data structure, with the @name lines.
+
+The longer description formatting is "reflowed", losing your line
+breaks.  So presenting carefully formatted lists within these
+descriptions won't work so well; derived documentation will lose
+the formatting.
+
+See the section below "How to add extractable documentation to your
+source files" for more details and notes on how to format kernel-doc
+comments.
+
+Components of the kernel-doc system
+-----------------------------------
+
 Many places in the source tree have extractable documentation in the
 form of block comments above functions.  The components of this system
 are:

Documentation/kernel-docs.txt

@@ -715,14 +715,14 @@
 
      * Name: "Gary's Encyclopedia - The Linux Kernel"
        Author: Gary (I suppose...).
-       URL: http://www.lisoleg.net/cgi-bin/lisoleg.pl?view=kernel.htm
-       Keywords: links, not found here?.
+       URL: http://slencyclopedia.berlios.de/index.html
+       Keywords: linux, community, everything!
        Description: Gary's Encyclopedia exists to allow the rapid finding
        of documentation and other information of interest to GNU/Linux
        users. It has about 4000 links to external pages in 150 major
        categories. This link is for kernel-specific links, documents,
-       sites... Look there if you could not find here what you were
-       looking for.
+       sites...  This list is now hosted by developer.Berlios.de,
+       but seems not to have been updated since sometime in 1999.
 
      * Name: "The home page of Linux-MM"
        Author: The Linux-MM team.

Documentation/kernel-parameters.txt

@@ -147,10 +147,14 @@ and is between 256 and 4096 characters. It is defined in the file
 			default: 0
 
 	acpi_sleep=	[HW,ACPI] Sleep options
-			Format: { s3_bios, s3_mode, s3_beep }
+			Format: { s3_bios, s3_mode, s3_beep, old_ordering }
 			See Documentation/power/video.txt for s3_bios and s3_mode.
 			s3_beep is for debugging; it makes the PC's speaker beep
 			as soon as the kernel's real-mode entry point is called.
+			old_ordering causes the ACPI 1.0 ordering of the _PTS
+			control method, wrt putting devices into low power
+			states, to be enforced (the ACPI 2.0 ordering of _PTS is
+			used by default).
 
 	acpi_sci=	[HW,ACPI] ACPI System Control Interrupt trigger mode
 			Format: { level | edge | high | low }
@@ -271,6 +275,17 @@ and is between 256 and 4096 characters. It is defined in the file
 	aic79xx=	[HW,SCSI]
 			See Documentation/scsi/aic79xx.txt.
 
+	amd_iommu=	[HW,X86-84]
+			Pass parameters to the AMD IOMMU driver in the system.
+			Possible values are:
+			isolate - enable device isolation (each device, as far
+			          as possible, will get its own protection
+			          domain)
+	amd_iommu_size= [HW,X86-64]
+			Define the size of the aperture for the AMD IOMMU
+			driver. Possible values are:
+			'32M', '64M' (default), '128M', '256M', '512M', '1G'
+
 	amijoy.map=	[HW,JOY] Amiga joystick support
 			Map of devices attached to JOY0DAT and JOY1DAT
 			Format: <a>,<b>
@@ -295,7 +310,7 @@ and is between 256 and 4096 characters. It is defined in the file
 			when initialising the APIC and IO-APIC components.
 
 	apm=		[APM] Advanced Power Management
-			See header of arch/i386/kernel/apm.c.
+			See header of arch/x86/kernel/apm_32.c.
 
 	arcrimi=	[HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
 			Format: <io>,<irq>,<nodeID>
@@ -560,6 +575,8 @@ and is between 256 and 4096 characters. It is defined in the file
 
 	debug_objects	[KNL] Enable object debugging
 
+	debugpat	[X86] Enable PAT debugging
+
 	decnet.addr=	[HW,NET]
 			Format: <area>[,<node>]
 			See also Documentation/networking/decnet.txt.
@@ -599,6 +616,29 @@ and is between 256 and 4096 characters. It is defined in the file
 			See drivers/char/README.epca and
 			Documentation/digiepca.txt.
 
+	disable_mtrr_cleanup [X86]
+	enable_mtrr_cleanup [X86]
+			The kernel tries to adjust MTRR layout from continuous
+			to discrete, to make X server driver able to add WB
+			entry later. This parameter enables/disables that.
+
+	mtrr_chunk_size=nn[KMG] [X86]
+			used for mtrr cleanup. It is largest continous chunk
+			that could hold holes aka. UC entries.
+
+	mtrr_gran_size=nn[KMG] [X86]
+			Used for mtrr cleanup. It is granularity of mtrr block.
+			Default is 1.
+			Large value could prevent small alignment from
+			using up MTRRs.
+
+	mtrr_spare_reg_nr=n [X86]
+			Format: <integer>
+			Range: 0,7 : spare reg number
+			Default : 1
+			Used for mtrr cleanup. It is spare mtrr entries number.
+			Set to 2 or more if your graphical card needs more.
+
 	disable_mtrr_trim [X86, Intel and AMD only]
 			By default the kernel will trim any uncacheable
 			memory out of your available memory pool based on
@@ -638,7 +678,7 @@ and is between 256 and 4096 characters. It is defined in the file
 
 	elanfreq=	[X86-32]
 			See comment before function elanfreq_setup() in
-			arch/i386/kernel/cpu/cpufreq/elanfreq.c.
+			arch/x86/kernel/cpu/cpufreq/elanfreq.c.
 
 	elevator=	[IOSCHED]
 			Format: {"anticipatory" | "cfq" | "deadline" | "noop"}
@@ -722,9 +762,6 @@ and is between 256 and 4096 characters. It is defined in the file
 	hd=		[EIDE] (E)IDE hard drive subsystem geometry
 			Format: <cyl>,<head>,<sect>
 
-	hd?=		[HW] (E)IDE subsystem
-	hd?lun=		See Documentation/ide/ide.txt.
-
 	highmem=nn[KMG]	[KNL,BOOT] forces the highmem zone to have an exact
 			size of <nn>. This works even on boxes that have no
 			highmem otherwise. This also works to reduce highmem
@@ -785,7 +822,7 @@ and is between 256 and 4096 characters. It is defined in the file
 			See Documentation/ide/ide.txt.
 
 	idle=		[X86]
-			Format: idle=poll or idle=mwait
+			Format: idle=poll or idle=mwait, idle=halt, idle=nomwait
 			Poll forces a polling idle loop that can slightly improves the performance
 			of waking up a idle CPU, but will use a lot of power and make the system
 			run hot. Not recommended.
@@ -793,6 +830,9 @@ and is between 256 and 4096 characters. It is defined in the file
 			to not use it because it doesn't save as much power as a normal idle
 			loop use the MONITOR/MWAIT idle loop anyways. Performance should be the same
 			as idle=poll.
+			idle=halt. Halt is forced to be used for CPU idle.
+			In such case C2/C3 won't be used again.
+			idle=nomwait. Disable mwait for CPU C-states
 
 	ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem
 			Claim all unknown PCI IDE storage controllers.
@@ -1208,6 +1248,11 @@ and is between 256 and 4096 characters. It is defined in the file
 	mtdparts=	[MTD]
 			See drivers/mtd/cmdlinepart.c.
 
+	mtdset=		[ARM]
+			ARM/S3C2412 JIVE boot control
+
+			See arch/arm/mach-s3c2412/mach-jive.c
+
 	mtouchusb.raw_coordinates=
 			[HW] Make the MicroTouch USB driver use raw coordinates
 			('y', default) or cooked coordinates ('n')
@@ -1496,6 +1541,9 @@ and is between 256 and 4096 characters. It is defined in the file
 				Use with caution as certain devices share
 				address decoders between ROMs and other
 				resources.
+		norom		[X86-32,X86_64] Do not assign address space to
+				expansion ROMs that do not already have
+				BIOS assigned address ranges.
 		irqmask=0xMMMM	[X86-32] Set a bit mask of IRQs allowed to be
 				assigned automatically to PCI devices. You can
 				make the kernel exclude IRQs of your ISA cards
@@ -1571,6 +1619,10 @@ and is between 256 and 4096 characters. It is defined in the file
 			Format: { parport<nr> | timid | 0 }
 			See also Documentation/parport.txt.
 
+	pmtmr=		[X86] Manual setup of pmtmr I/O Port. 
+			Override pmtimer IOPort with a hex value.
+			e.g. pmtmr=0x508
+
 	pnpacpi=	[ACPI]
 			{ off }
 
@@ -1679,6 +1731,10 @@ and is between 256 and 4096 characters. It is defined in the file
 			Format: <reboot_mode>[,<reboot_mode2>[,...]]
 			See arch/*/kernel/reboot.c or arch/*/kernel/process.c			
 
+	relax_domain_level=
+			[KNL, SMP] Set scheduler's default relax_domain_level.
+			See Documentation/cpusets.txt.
+
 	reserve=	[KNL,BUGS] Force the kernel to ignore some iomem area
 
 	reservetop=	[X86-32]
@@ -2112,6 +2168,9 @@ and is between 256 and 4096 characters. It is defined in the file
 	usbhid.mousepoll=
 			[USBHID] The interval which mice are to be polled at.
 
+	add_efi_memmap	[EFI; x86-32,X86-64] Include EFI memory map in
+			kernel's map of available physical RAM.
+
 	vdso=		[X86-32,SH,x86-64]
 			vdso=2: enable compat VDSO (default with COMPAT_VDSO)
 			vdso=1: enable VDSO (default)

Documentation/kobject.txt

@@ -305,7 +305,7 @@ should not be manipulated by any other user.
 
 A kset keeps its children in a standard kernel linked list.  Kobjects point
 back to their containing kset via their kset field. In almost all cases,
-the kobjects belonging to a ket have that kset (or, strictly, its embedded
+the kobjects belonging to a kset have that kset (or, strictly, its embedded
 kobject) in their parent.
 
 As a kset contains a kobject within it, it should always be dynamically

Documentation/kprobes.txt

@@ -172,6 +172,7 @@ architectures:
 - ia64 (Does not support probes on instruction slot1.)
 - sparc64 (Return probes not yet implemented.)
 - arm
+- ppc
 
 3. Configuring Kprobes
 

Documentation/laptops/acer-wmi.txt

@@ -174,8 +174,6 @@ The LED is exposed through the LED subsystem, and can be found in:
 The mail LED is autodetected, so if you don't have one, the LED device won't
 be registered.
 
-If you have a mail LED that is not green, please report this to me.
-
 Backlight
 *********
 

Documentation/laptops/thinkpad-acpi.txt

@@ -503,7 +503,7 @@ generate input device EV_KEY events.
 In addition to the EV_KEY events, thinkpad-acpi may also issue EV_SW
 events for switches:
 
-SW_RADIO	T60 and later hardare rfkill rocker switch
+SW_RFKILL_ALL	T60 and later hardare rfkill rocker switch
 SW_TABLET_MODE	Tablet ThinkPads HKEY events 0x5009 and 0x500A
 
 Non hot-key ACPI HKEY event map:

Documentation/lguest/lguest.c

@@ -157,6 +157,9 @@ struct virtqueue
 
 	/* The routine to call when the Guest pings us. */
 	void (*handle_output)(int fd, struct virtqueue *me);
+
+	/* Outstanding buffers */
+	unsigned int inflight;
 };
 
 /* Remember the arguments to the program so we can "reboot" */
@@ -702,6 +705,7 @@ static unsigned get_vq_desc(struct virtqueue *vq,
 			errx(1, "Looped descriptor");
 	} while ((i = next_desc(vq, i)) != vq->vring.num);
 
+	vq->inflight++;
 	return head;
 }
 
@@ -719,6 +723,7 @@ static void add_used(struct virtqueue *vq, unsigned int head, int len)
 	/* Make sure buffer is written before we update index. */
 	wmb();
 	vq->vring.used->idx++;
+	vq->inflight--;
 }
 
 /* This actually sends the interrupt for this virtqueue */
@@ -726,8 +731,9 @@ static void trigger_irq(int fd, struct virtqueue *vq)
 {
 	unsigned long buf[] = { LHREQ_IRQ, vq->config.irq };
 
-	/* If they don't want an interrupt, don't send one. */
-	if (vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT)
+	/* If they don't want an interrupt, don't send one, unless empty. */
+	if ((vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT)
+	    && vq->inflight)
 		return;
 
 	/* Send the Guest an interrupt tell them we used something up. */
@@ -1107,6 +1113,7 @@ static void add_virtqueue(struct device *dev, unsigned int num_descs,
 	vq->next = NULL;
 	vq->last_avail_idx = 0;
 	vq->dev = dev;
+	vq->inflight = 0;
 
 	/* Initialize the configuration. */
 	vq->config.num = num_descs;
@@ -1368,6 +1375,7 @@ static void setup_tun_net(const char *arg)
 
 	/* Tell Guest what MAC address to use. */
 	add_feature(dev, VIRTIO_NET_F_MAC);
+	add_feature(dev, VIRTIO_F_NOTIFY_ON_EMPTY);
 	set_config(dev, sizeof(conf), &conf);
 
 	/* We don't need the socket any more; setup is done. */

Documentation/networking/arcnet.txt

@@ -46,7 +46,7 @@ These are the ARCnet drivers for Linux.
 
 
 This new release (2.91) has been put together by David Woodhouse 
-<dwmw2@cam.ac.uk>, in an attempt to tidy up the driver after adding support 
+<dwmw2@infradead.org>, in an attempt to tidy up the driver after adding support
 for yet another chipset. Now the generic support has been separated from the
 individual chipset drivers, and the source files aren't quite so packed with
 #ifdefs! I've changed this file a bit, but kept it in the first person from

Documentation/networking/bonding.txt

@@ -289,35 +289,73 @@ downdelay
 fail_over_mac
 
 	Specifies whether active-backup mode should set all slaves to
-	the same MAC address (the traditional behavior), or, when
-	enabled, change the bond's MAC address when changing the
-	active interface (i.e., fail over the MAC address itself).
-
-	Fail over MAC is useful for devices that cannot ever alter
-	their MAC address, or for devices that refuse incoming
-	broadcasts with their own source MAC (which interferes with
-	the ARP monitor).
-
-	The down side of fail over MAC is that every device on the
-	network must be updated via gratuitous ARP, vs. just updating
-	a switch or set of switches (which often takes place for any
-	traffic, not just ARP traffic, if the switch snoops incoming
-	traffic to update its tables) for the traditional method.  If
-	the gratuitous ARP is lost, communication may be disrupted.
-
-	When fail over MAC is used in conjuction with the mii monitor,
-	devices which assert link up prior to being able to actually
-	transmit and receive are particularly susecptible to loss of
-	the gratuitous ARP, and an appropriate updelay setting may be
-	required.
-
-	A value of 0 disables fail over MAC, and is the default.  A
-	value of 1 enables fail over MAC.  This option is enabled
-	automatically if the first slave added cannot change its MAC
-	address.  This option may be modified via sysfs only when no
-	slaves are present in the bond.
-
-	This option was added in bonding version 3.2.0.
+	the same MAC address at enslavement (the traditional
+	behavior), or, when enabled, perform special handling of the
+	bond's MAC address in accordance with the selected policy.
+
+	Possible values are:
+
+	none or 0
+
+		This setting disables fail_over_mac, and causes
+		bonding to set all slaves of an active-backup bond to
+		the same MAC address at enslavement time.  This is the
+		default.
+
+	active or 1
+
+		The "active" fail_over_mac policy indicates that the
+		MAC address of the bond should always be the MAC
+		address of the currently active slave.  The MAC
+		address of the slaves is not changed; instead, the MAC
+		address of the bond changes during a failover.
+
+		This policy is useful for devices that cannot ever
+		alter their MAC address, or for devices that refuse
+		incoming broadcasts with their own source MAC (which
+		interferes with the ARP monitor).
+
+		The down side of this policy is that every device on
+		the network must be updated via gratuitous ARP,
+		vs. just updating a switch or set of switches (which
+		often takes place for any traffic, not just ARP
+		traffic, if the switch snoops incoming traffic to
+		update its tables) for the traditional method.  If the
+		gratuitous ARP is lost, communication may be
+		disrupted.
+
+		When this policy is used in conjuction with the mii
+		monitor, devices which assert link up prior to being
+		able to actually transmit and receive are particularly
+		susecptible to loss of the gratuitous ARP, and an
+		appropriate updelay setting may be required.
+
+	follow or 2
+
+		The "follow" fail_over_mac policy causes the MAC
+		address of the bond to be selected normally (normally
+		the MAC address of the first slave added to the bond).
+		However, the second and subsequent slaves are not set
+		to this MAC address while they are in a backup role; a
+		slave is programmed with the bond's MAC address at
+		failover time (and the formerly active slave receives
+		the newly active slave's MAC address).
+
+		This policy is useful for multiport devices that
+		either become confused or incur a performance penalty
+		when multiple ports are programmed with the same MAC
+		address.
+
+
+	The default policy is none, unless the first slave cannot
+	change its MAC address, in which case the active policy is
+	selected by default.
+
+	This option may be modified via sysfs only when no slaves are
+	present in the bond.
+
+	This option was added in bonding version 3.2.0.  The "follow"
+	policy was added in bonding version 3.3.0.
 
 lacp_rate
 
@@ -338,7 +376,8 @@ max_bonds
 	Specifies the number of bonding devices to create for this
 	instance of the bonding driver.  E.g., if max_bonds is 3, and
 	the bonding driver is not already loaded, then bond0, bond1
-	and bond2 will be created.  The default value is 1.
+	and bond2 will be created.  The default value is 1.  Specifying
+	a value of 0 will load bonding, but will not create any devices.
 
 miimon
 
@@ -501,6 +540,17 @@ mode
 		swapped with the new curr_active_slave that was
 		chosen.
 
+num_grat_arp
+
+	Specifies the number of gratuitous ARPs to be issued after a
+	failover event.  One gratuitous ARP is issued immediately after
+	the failover, subsequent ARPs are sent at a rate of one per link
+	monitor interval (arp_interval or miimon, whichever is active).
+
+	The valid range is 0 - 255; the default value is 1.  This option
+	affects only the active-backup mode.  This option was added for
+	bonding version 3.3.0.
+
 primary
 
 	A string (eth0, eth2, etc) specifying which slave is the

Documentation/networking/bridge.txt

@@ -1,6 +1,6 @@
 In order to use the Ethernet bridging functionality, you'll need the
 userspace tools. These programs and documentation are available
-at http://bridge.sourceforge.net.  The download page is
+at http://www.linux-foundation.org/en/Net:Bridge.  The download page is
 http://prdownloads.sourceforge.net/bridge.
 
 If you still have questions, don't hesitate to post to the mailing list 

Documentation/networking/dm9000.txt

@@ -0,0 +1,167 @@
+DM9000 Network driver
+=====================
+
+Copyright 2008 Simtec Electronics,
+	  Ben Dooks <ben@simtec.co.uk> <ben-linux@fluff.org>
+
+
+Introduction
+------------
+
+This file describes how to use the DM9000 platform-device based network driver
+that is contained in the files drivers/net/dm9000.c and drivers/net/dm9000.h.
+
+The driver supports three DM9000 variants, the DM9000E which is the first chip
+supported as well as the newer DM9000A and DM9000B devices. It is currently
+maintained and tested by Ben Dooks, who should be CC: to any patches for this
+driver.
+
+
+Defining the platform device
+----------------------------
+
+The minimum set of resources attached to the platform device are as follows:
+
+    1) The physical address of the address register
+    2) The physical address of the data register
+    3) The IRQ line the device's interrupt pin is connected to.
+
+These resources should be specified in that order, as the ordering of the
+two address regions is important (the driver expects these to be address
+and then data).
+
+An example from arch/arm/mach-s3c2410/mach-bast.c is:
+
+static struct resource bast_dm9k_resource[] = {
+	[0] = {
+		.start = S3C2410_CS5 + BAST_PA_DM9000,
+		.end   = S3C2410_CS5 + BAST_PA_DM9000 + 3,
+		.flags = IORESOURCE_MEM,
+	},
+	[1] = {
+		.start = S3C2410_CS5 + BAST_PA_DM9000 + 0x40,
+		.end   = S3C2410_CS5 + BAST_PA_DM9000 + 0x40 + 0x3f,
+		.flags = IORESOURCE_MEM,
+	},
+	[2] = {
+		.start = IRQ_DM9000,
+		.end   = IRQ_DM9000,
+		.flags = IORESOURCE_IRQ | IORESOURCE_IRQ_HIGHLEVEL,
+	}
+};
+
+static struct platform_device bast_device_dm9k = {
+	.name		= "dm9000",
+	.id		= 0,
+	.num_resources	= ARRAY_SIZE(bast_dm9k_resource),
+	.resource	= bast_dm9k_resource,
+};
+
+Note the setting of the IRQ trigger flag in bast_dm9k_resource[2].flags,
+as this will generate a warning if it is not present. The trigger from
+the flags field will be passed to request_irq() when registering the IRQ
+handler to ensure that the IRQ is setup correctly.
+
+This shows a typical platform device, without the optional configuration
+platform data supplied. The next example uses the same resources, but adds
+the optional platform data to pass extra configuration data:
+
+static struct dm9000_plat_data bast_dm9k_platdata = {
+	.flags		= DM9000_PLATF_16BITONLY,
+};
+
+static struct platform_device bast_device_dm9k = {
+	.name		= "dm9000",
+	.id		= 0,
+	.num_resources	= ARRAY_SIZE(bast_dm9k_resource),
+	.resource	= bast_dm9k_resource,
+	.dev		= {
+		.platform_data = &bast_dm9k_platdata,
+	}
+};
+
+The platform data is defined in include/linux/dm9000.h and described below.
+
+
+Platform data
+-------------
+
+Extra platform data for the DM9000 can describe the IO bus width to the
+device, whether or not an external PHY is attached to the device and
+the availability of an external configuration EEPROM.
+
+The flags for the platform data .flags field are as follows:
+
+DM9000_PLATF_8BITONLY
+
+	The IO should be done with 8bit operations.
+
+DM9000_PLATF_16BITONLY
+
+	The IO should be done with 16bit operations.
+
+DM9000_PLATF_32BITONLY
+
+	The IO should be done with 32bit operations.
+
+DM9000_PLATF_EXT_PHY
+
+	The chip is connected to an external PHY.
+
+DM9000_PLATF_NO_EEPROM
+
+	This can be used to signify that the board does not have an
+	EEPROM, or that the EEPROM should be hidden from the user.
+
+DM9000_PLATF_SIMPLE_PHY
+
+	Switch to using the simpler PHY polling method which does not
+	try and read the MII PHY state regularly. This is only available
+	when using the internal PHY. See the section on link state polling
+	for more information.
+
+	The config symbol DM9000_FORCE_SIMPLE_PHY_POLL, Kconfig entry
+	"Force simple NSR based PHY polling" allows this flag to be
+	forced on at build time.
+
+
+PHY Link state polling
+----------------------
+
+The driver keeps track of the link state and informs the network core
+about link (carrier) availablilty. This is managed by several methods
+depending on the version of the chip and on which PHY is being used.
+
+For the internal PHY, the original (and currently default) method is
+to read the MII state, either when the status changes if we have the
+necessary interrupt support in the chip or every two seconds via a
+periodic timer.
+
+To reduce the overhead for the internal PHY, there is now the option
+of using the DM9000_FORCE_SIMPLE_PHY_POLL config, or DM9000_PLATF_SIMPLE_PHY
+platform data option to read the summary information without the
+expensive MII accesses. This method is faster, but does not print
+as much information.
+
+When using an external PHY, the driver currently has to poll the MII
+link status as there is no method for getting an interrupt on link change.
+
+
+DM9000A / DM9000B
+-----------------
+
+These chips are functionally similar to the DM9000E and are supported easily
+by the same driver. The features are:
+
+   1) Interrupt on internal PHY state change. This means that the periodic
+      polling of the PHY status may be disabled on these devices when using
+      the internal PHY.
+
+   2) TCP/UDP checksum offloading, which the driver does not currently support.
+
+
+ethtool
+-------
+
+The driver supports the ethtool interface for access to the driver
+state information, the PHY state and the EEPROM.

Documentation/networking/ip-sysctl.txt

@@ -81,23 +81,23 @@ inet_peer_minttl - INTEGER
 	Minimum time-to-live of entries.  Should be enough to cover fragment
 	time-to-live on the reassembling side.  This minimum time-to-live  is
 	guaranteed if the pool size is less than inet_peer_threshold.
-	Measured in jiffies(1).
+	Measured in seconds.
 
 inet_peer_maxttl - INTEGER
 	Maximum time-to-live of entries.  Unused entries will expire after
 	this period of time if there is no memory pressure on the pool (i.e.
 	when the number of entries in the pool is very small).
-	Measured in jiffies(1).
+	Measured in seconds.
 
 inet_peer_gc_mintime - INTEGER
 	Minimum interval between garbage collection passes.  This interval is
 	in effect under high memory pressure on the pool.
-	Measured in jiffies(1).
+	Measured in seconds.
 
 inet_peer_gc_maxtime - INTEGER
 	Minimum interval between garbage collection passes.  This interval is
 	in effect under low (or absent) memory pressure on the pool.
-	Measured in jiffies(1).
+	Measured in seconds.
 
 TCP variables: 
 
@@ -148,9 +148,9 @@ tcp_available_congestion_control - STRING
 	but not loaded.
 
 tcp_base_mss - INTEGER
-	The initial value of search_low to be used by Packetization Layer
-	Path MTU Discovery (MTU probing).  If MTU probing is enabled,
-	this is the inital MSS used by the connection.
+	The initial value of search_low to be used by the packetization layer
+	Path MTU discovery (MTU probing).  If MTU probing is enabled,
+	this is the initial MSS used by the connection.
 
 tcp_congestion_control - STRING
 	Set the congestion control algorithm to be used for new
@@ -185,10 +185,9 @@ tcp_frto - INTEGER
 	timeouts.  It is particularly beneficial in wireless environments
 	where packet loss is typically due to random radio interference
 	rather than intermediate router congestion.  F-RTO is sender-side
-	only modification.  Therefore it does not require any support from
-	the peer, but in a typical case, however, where wireless link is
-	the local access link and most of the data flows downlink, the
-	faraway servers should have F-RTO enabled to take advantage of it.
+	only modification. Therefore it does not require any support from
+	the peer.
+
 	If set to 1, basic version is enabled.  2 enables SACK enhanced
 	F-RTO if flow uses SACK.  The basic version can be used also when
 	SACK is in use though scenario(s) with it exists where F-RTO
@@ -276,7 +275,7 @@ tcp_mem - vector of 3 INTEGERs: min, pressure, max
 	memory.
 
 tcp_moderate_rcvbuf - BOOLEAN
-	If set, TCP performs receive buffer autotuning, attempting to
+	If set, TCP performs receive buffer auto-tuning, attempting to
 	automatically size the buffer (no greater than tcp_rmem[2]) to
 	match the size required by the path for full throughput.  Enabled by
 	default.
@@ -336,7 +335,7 @@ tcp_rmem - vector of 3 INTEGERs: min, default, max
 	pressure.
 	Default: 8K
 
-	default: default size of receive buffer used by TCP sockets.
+	default: initial size of receive buffer used by TCP sockets.
 	This value overrides net.core.rmem_default used by other protocols.
 	Default: 87380 bytes. This value results in window of 65535 with
 	default setting of tcp_adv_win_scale and tcp_app_win:0 and a bit
@@ -344,8 +343,10 @@ tcp_rmem - vector of 3 INTEGERs: min, default, max
 
 	max: maximal size of receive buffer allowed for automatically
 	selected receiver buffers for TCP socket. This value does not override
-	net.core.rmem_max, "static" selection via SO_RCVBUF does not use this.
-	Default: 87380*2 bytes.
+	net.core.rmem_max.  Calling setsockopt() with SO_RCVBUF disables
+	automatic tuning of that socket's receive buffer size, in which
+	case this value is ignored.
+	Default: between 87380B and 4MB, depending on RAM size.
 
 tcp_sack - BOOLEAN
 	Enable select acknowledgments (SACKS).
@@ -358,7 +359,7 @@ tcp_slow_start_after_idle - BOOLEAN
 	Default: 1
 
 tcp_stdurg - BOOLEAN
-	Use the Host requirements interpretation of the TCP urg pointer field.
+	Use the Host requirements interpretation of the TCP urgent pointer field.
 	Most hosts use the older BSD interpretation, so if you turn this on
 	Linux might not communicate correctly with them.
 	Default: FALSE
@@ -371,12 +372,12 @@ tcp_synack_retries - INTEGER
 tcp_syncookies - BOOLEAN
 	Only valid when the kernel was compiled with CONFIG_SYNCOOKIES
 	Send out syncookies when the syn backlog queue of a socket
-	overflows. This is to prevent against the common 'syn flood attack'
+	overflows. This is to prevent against the common 'SYN flood attack'
 	Default: FALSE
 
 	Note, that syncookies is fallback facility.
 	It MUST NOT be used to help highly loaded servers to stand
-	against legal connection rate. If you see synflood warnings
+	against legal connection rate. If you see SYN flood warnings
 	in your logs, but investigation	shows that they occur
 	because of overload with legal connections, you should tune
 	another parameters until this warning disappear.
@@ -386,7 +387,7 @@ tcp_syncookies - BOOLEAN
 	to use TCP extensions, can result in serious degradation
 	of some services (f.e. SMTP relaying), visible not by you,
 	but your clients and relays, contacting you. While you see
-	synflood warnings in logs not being really flooded, your server
+	SYN flood warnings in logs not being really flooded, your server
 	is seriously misconfigured.
 
 tcp_syn_retries - INTEGER
@@ -419,19 +420,21 @@ tcp_window_scaling - BOOLEAN
 	Enable window scaling as defined in RFC1323.
 
 tcp_wmem - vector of 3 INTEGERs: min, default, max
-	min: Amount of memory reserved for send buffers for TCP socket.
+	min: Amount of memory reserved for send buffers for TCP sockets.
 	Each TCP socket has rights to use it due to fact of its birth.
 	Default: 4K
 
-	default: Amount of memory allowed for send buffers for TCP socket
-	by default. This value overrides net.core.wmem_default used
-	by other protocols, it is usually lower than net.core.wmem_default.
+	default: initial size of send buffer used by TCP sockets.  This
+	value overrides net.core.wmem_default used by other protocols.
+	It is usually lower than net.core.wmem_default.
 	Default: 16K
 
-	max: Maximal amount of memory allowed for automatically selected
-	send buffers for TCP socket. This value does not override
-	net.core.wmem_max, "static" selection via SO_SNDBUF does not use this.
-	Default: 128K
+	max: Maximal amount of memory allowed for automatically tuned
+	send buffers for TCP sockets. This value does not override
+	net.core.wmem_max.  Calling setsockopt() with SO_SNDBUF disables
+	automatic tuning of that socket's send buffer size, in which case
+	this value is ignored.
+	Default: between 64K and 4MB, depending on RAM size.
 
 tcp_workaround_signed_windows - BOOLEAN
 	If set, assume no receipt of a window scaling option means the
@@ -548,8 +551,9 @@ icmp_echo_ignore_broadcasts - BOOLEAN
 icmp_ratelimit - INTEGER
 	Limit the maximal rates for sending ICMP packets whose type matches
 	icmp_ratemask (see below) to specific targets.
-	0 to disable any limiting, otherwise the maximal rate in jiffies(1)
-	Default: 100
+	0 to disable any limiting,
+	otherwise the minimal space between responses in milliseconds.
+	Default: 1000
 
 icmp_ratemask - INTEGER
 	Mask made of ICMP types for which rates are being limited.
@@ -794,10 +798,6 @@ tag - INTEGER
 	Allows you to write a number, which can be used as required.
 	Default value is 0.
 
-(1) Jiffie: internal timeunit for the kernel. On the i386 1/100s, on the
-Alpha 1/1024s. See the HZ define in /usr/include/asm/param.h for the exact
-value on your system. 
-
 Alexey Kuznetsov.
 kuznet@ms2.inr.ac.ru
 
@@ -1024,11 +1024,23 @@ max_addresses - INTEGER
 	autoconfigured addresses.
 	Default: 16
 
+disable_ipv6 - BOOLEAN
+	Disable IPv6 operation.
+	Default: FALSE (enable IPv6 operation)
+
+accept_dad - INTEGER
+	Whether to accept DAD (Duplicate Address Detection).
+	0: Disable DAD
+	1: Enable DAD (default)
+	2: Enable DAD, and disable IPv6 operation if MAC-based duplicate
+	   link-local address has been found.
+
 icmp/*:
 ratelimit - INTEGER
 	Limit the maximal rates for sending ICMPv6 packets.
-	0 to disable any limiting, otherwise the maximal rate in jiffies(1)
-	Default: 100
+	0 to disable any limiting,
+	otherwise the minimal space between responses in milliseconds.
+	Default: 1000
 
 
 IPv6 Update by:
@@ -1064,24 +1076,193 @@ bridge-nf-filter-pppoe-tagged - BOOLEAN
 	Default: 1
 
 
-UNDOCUMENTED:
+proc/sys/net/sctp/* Variables:
+
+addip_enable - BOOLEAN
+	Enable or disable extension of  Dynamic Address Reconfiguration
+	(ADD-IP) functionality specified in RFC5061.  This extension provides
+	the ability to dynamically add and remove new addresses for the SCTP
+	associations.
+
+	1: Enable extension.
+
+	0: Disable extension.
+
+	Default: 0
+
+addip_noauth_enable - BOOLEAN
+	Dynamic Address Reconfiguration (ADD-IP) requires the use of
+	authentication to protect the operations of adding or removing new
+	addresses.  This requirement is mandated so that unauthorized hosts
+	would not be able to hijack associations.  However, older
+	implementations may not have implemented this requirement while
+	allowing the ADD-IP extension.  For reasons of interoperability,
+	we provide this variable to control the enforcement of the
+	authentication requirement.
+
+	1: Allow ADD-IP extension to be used without authentication.  This
+	   should only be set in a closed environment for interoperability
+	   with older implementations.
+
+	0: Enforce the authentication requirement
+
+	Default: 0
+
+auth_enable - BOOLEAN
+	Enable or disable Authenticated Chunks extension.  This extension
+	provides the ability to send and receive authenticated chunks and is
+	required for secure operation of Dynamic Address Reconfiguration
+	(ADD-IP) extension.
+
+	1: Enable this extension.
+	0: Disable this extension.
+
+	Default: 0
+
+prsctp_enable - BOOLEAN
+	Enable or disable the Partial Reliability extension (RFC3758) which
+	is used to notify peers that a given DATA should no longer be expected.
+
+	1: Enable extension
+	0: Disable
+
+	Default: 1
+
+max_burst - INTEGER
+	The limit of the number of new packets that can be initially sent.  It
+	controls how bursty the generated traffic can be.
+
+	Default: 4
+
+association_max_retrans - INTEGER
+	Set the maximum number for retransmissions that an association can
+	attempt deciding that the remote end is unreachable.  If this value
+	is exceeded, the association is terminated.
+
+	Default: 10
+
+max_init_retransmits - INTEGER
+	The maximum number of retransmissions of INIT and COOKIE-ECHO chunks
+	that an association will attempt before declaring the destination
+	unreachable and terminating.
+
+	Default: 8
+
+path_max_retrans - INTEGER
+	The maximum number of retransmissions that will be attempted on a given
+	path.  Once this threshold is exceeded, the path is considered
+	unreachable, and new traffic will use a different path when the
+	association is multihomed.
+
+	Default: 5
 
-dev_weight FIXME
-discovery_slots FIXME
-discovery_timeout FIXME
-fast_poll_increase FIXME
-ip6_queue_maxlen FIXME
-lap_keepalive_time FIXME
-lo_cong FIXME
-max_baud_rate FIXME
-max_dgram_qlen FIXME
-max_noreply_time FIXME
-max_tx_data_size FIXME
-max_tx_window FIXME
-min_tx_turn_time FIXME
-mod_cong FIXME
-no_cong FIXME
-no_cong_thresh FIXME
-slot_timeout FIXME
-warn_noreply_time FIXME
+rto_initial - INTEGER
+	The initial round trip timeout value in milliseconds that will be used
+	in calculating round trip times.  This is the initial time interval
+	for retransmissions.
+
+	Default: 3000
+
+rto_max - INTEGER
+	The maximum value (in milliseconds) of the round trip timeout.  This
+	is the largest time interval that can elapse between retransmissions.
+
+	Default: 60000
+
+rto_min - INTEGER
+	The minimum value (in milliseconds) of the round trip timeout.  This
+	is the smallest time interval the can elapse between retransmissions.
+
+	Default: 1000
+
+hb_interval - INTEGER
+	The interval (in milliseconds) between HEARTBEAT chunks.  These chunks
+	are sent at the specified interval on idle paths to probe the state of
+	a given path between 2 associations.
+
+	Default: 30000
+
+sack_timeout - INTEGER
+	The amount of time (in milliseconds) that the implementation will wait
+	to send a SACK.
+
+	Default: 200
+
+valid_cookie_life - INTEGER
+	The default lifetime of the SCTP cookie (in milliseconds).  The cookie
+	is used during association establishment.
+
+	Default: 60000
+
+cookie_preserve_enable - BOOLEAN
+	Enable or disable the ability to extend the lifetime of the SCTP cookie
+	that is used during the establishment phase of SCTP association
+
+	1: Enable cookie lifetime extension.
+	0: Disable
+
+	Default: 1
+
+rcvbuf_policy - INTEGER
+	Determines if the receive buffer is attributed to the socket or to
+	association.   SCTP supports the capability to create multiple
+	associations on a single socket.  When using this capability, it is
+	possible that a single stalled association that's buffering a lot
+	of data may block other associations from delivering their data by
+	consuming all of the receive buffer space.  To work around this,
+	the rcvbuf_policy could be set to attribute the receiver buffer space
+	to each association instead of the socket.  This prevents the described
+	blocking.
+
+	1: rcvbuf space is per association
+	0: recbuf space is per socket
+
+	Default: 0
+
+sndbuf_policy - INTEGER
+	Similar to rcvbuf_policy above, this applies to send buffer space.
+
+	1: Send buffer is tracked per association
+	0: Send buffer is tracked per socket.
+
+	Default: 0
+
+sctp_mem - vector of 3 INTEGERs: min, pressure, max
+	Number of pages allowed for queueing by all SCTP sockets.
+
+	min: Below this number of pages SCTP is not bothered about its
+	memory appetite. When amount of memory allocated by SCTP exceeds
+	this number, SCTP starts to moderate memory usage.
+
+	pressure: This value was introduced to follow format of tcp_mem.
+
+	max: Number of pages allowed for queueing by all SCTP sockets.
+
+	Default is calculated at boot time from amount of available memory.
+
+sctp_rmem - vector of 3 INTEGERs: min, default, max
+	See tcp_rmem for a description.
+
+sctp_wmem  - vector of 3 INTEGERs: min, default, max
+	See tcp_wmem for a description.
+
+UNDOCUMENTED:
 
+/proc/sys/net/core/*
+	dev_weight FIXME
+
+/proc/sys/net/unix/*
+	max_dgram_qlen FIXME
+
+/proc/sys/net/irda/*
+	fast_poll_increase FIXME
+	warn_noreply_time FIXME
+	discovery_slots FIXME
+	slot_timeout FIXME
+	max_baud_rate FIXME
+	discovery_timeout FIXME
+	lap_keepalive_time FIXME
+	max_noreply_time FIXME
+	max_tx_data_size FIXME
+	max_tx_window FIXME
+	min_tx_turn_time FIXME

Documentation/networking/ixgb.txt

@@ -1,7 +1,7 @@
-Linux* Base Driver for the Intel(R) PRO/10GbE Family of Adapters
-================================================================
+Linux Base Driver for 10 Gigabit Intel(R) Network Connection
+=============================================================
 
-November 17, 2004
+October 9, 2007
 
 
 Contents
@@ -9,94 +9,151 @@ Contents
 
 - In This Release
 - Identifying Your Adapter
+- Building and Installation
 - Command Line Parameters
 - Improving Performance
+- Additional Configurations
+- Known Issues/Troubleshooting
 - Support
 
 
+
 In This Release
 ===============
 
-This file describes the Linux* Base Driver for the Intel(R) PRO/10GbE Family 
-of Adapters, version 1.0.x.  
+This file describes the ixgb Linux Base Driver for the 10 Gigabit Intel(R)
+Network Connection.  This driver includes support for Itanium(R)2-based
+systems.
+
+For questions related to hardware requirements, refer to the documentation
+supplied with your 10 Gigabit adapter.  All hardware requirements listed apply
+to use with Linux.
+
+The following features are available in this kernel:
+ - Native VLANs
+ - Channel Bonding (teaming)
+ - SNMP
+
+Channel Bonding documentation can be found in the Linux kernel source:
+/Documentation/networking/bonding.txt
+
+The driver information previously displayed in the /proc filesystem is not
+supported in this release.  Alternatively, you can use ethtool (version 1.6
+or later), lspci, and ifconfig to obtain the same information.
+
+Instructions on updating ethtool can be found in the section "Additional
+Configurations" later in this document.
 
-For questions related to hardware requirements, refer to the documentation 
-supplied with your Intel PRO/10GbE adapter. All hardware requirements listed 
-apply to use with Linux.
 
 Identifying Your Adapter
 ========================
 
-To verify your Intel adapter is supported, find the board ID number on the 
-adapter. Look for a label that has a barcode and a number in the format  
-A12345-001. 
+The following Intel network adapters are compatible with the drivers in this
+release:
+
+Controller  Adapter Name                 Physical Layer
+----------  ------------                 --------------
+82597EX     Intel(R) PRO/10GbE LR/SR/CX4 10G Base-LR (1310 nm optical fiber)
+            Server Adapters              10G Base-SR (850 nm optical fiber)
+                                         10G Base-CX4(twin-axial copper cabling)
+
+For more information on how to identify your adapter, go to the Adapter &
+Driver ID Guide at:
+
+    http://support.intel.com/support/network/sb/CS-012904.htm
+
+
+Building and Installation
+=========================
+
+select m for "Intel(R) PRO/10GbE support" located at:
+      Location:
+        -> Device Drivers
+          -> Network device support (NETDEVICES [=y])
+            -> Ethernet (10000 Mbit) (NETDEV_10000 [=y])
+1. make modules && make modules_install
+
+2. Load the module:
+
+    modprobe ixgb <parameter>=<value>
+
+   The insmod command can be used if the full
+   path to the driver module is specified.  For example:
+
+     insmod /lib/modules/<KERNEL VERSION>/kernel/drivers/net/ixgb/ixgb.ko
+
+   With 2.6 based kernels also make sure that older ixgb drivers are
+   removed from the kernel, before loading the new module:
 
-Use the above information and the Adapter & Driver ID Guide at:
+     rmmod ixgb; modprobe ixgb
 
-  http://support.intel.com/support/network/adapter/pro100/21397.htm
+3. Assign an IP address to the interface by entering the following, where
+   x is the interface number:
 
-For the latest Intel network drivers for Linux, go to:
+     ifconfig ethx <IP_address>
+
+4. Verify that the interface works. Enter the following, where <IP_address>
+   is the IP address for another machine on the same subnet as the interface
+   that is being tested:
+
+     ping  <IP_address>
 
-    http://downloadfinder.intel.com/scripts-df/support_intel.asp
 
 Command Line Parameters
 =======================
 
-If the driver is built as a module, the  following optional parameters are 
-used by entering them on the command line with the modprobe or insmod command
-using this syntax:
+If the driver is built as a module, the  following optional parameters are
+used by entering them on the command line with the modprobe command using
+this syntax:
 
      modprobe ixgb [<option>=<VAL1>,<VAL2>,...]
 
-     insmod ixgb [<option>=<VAL1>,<VAL2>,...]
+For example, with two 10GbE PCI adapters, entering:
 
-For example, with two PRO/10GbE PCI adapters, entering:
+     modprobe ixgb TxDescriptors=80,128
 
-    insmod ixgb TxDescriptors=80,128
-
-loads the ixgb driver with 80 TX resources for the first adapter and 128 TX 
+loads the ixgb driver with 80 TX resources for the first adapter and 128 TX
 resources for the second adapter.
 
 The default value for each parameter is generally the recommended setting,
-unless otherwise noted. Also, if the driver is statically built into the
-kernel, the driver is loaded with the default values for all the parameters.
-Ethtool can be used to change some of the parameters at runtime.
+unless otherwise noted.
 
 FlowControl
 Valid Range: 0-3 (0=none, 1=Rx only, 2=Tx only, 3=Rx&Tx)
 Default: Read from the EEPROM
-         If EEPROM is not detected, default is 3
-    This parameter controls the automatic generation(Tx) and response(Rx) to 
-    Ethernet PAUSE frames.
+         If EEPROM is not detected, default is 1
+    This parameter controls the automatic generation(Tx) and response(Rx) to
+    Ethernet PAUSE frames.  There are hardware bugs associated with enabling
+    Tx flow control so beware.
 
 RxDescriptors
 Valid Range: 64-512
 Default Value: 512
-    This value is the number of receive descriptors allocated by the driver. 
-    Increasing this value allows the driver to buffer more incoming packets. 
-    Each descriptor is 16 bytes.  A receive buffer is also allocated for 
-    each descriptor and can be either 2048, 4056, 8192, or 16384 bytes, 
-    depending on the MTU setting. When the MTU size is 1500 or less, the 
+    This value is the number of receive descriptors allocated by the driver.
+    Increasing this value allows the driver to buffer more incoming packets.
+    Each descriptor is 16 bytes.  A receive buffer is also allocated for
+    each descriptor and can be either 2048, 4056, 8192, or 16384 bytes,
+    depending on the MTU setting.  When the MTU size is 1500 or less, the
     receive buffer size is 2048 bytes. When the MTU is greater than 1500 the
-    receive buffer size will be either 4056, 8192, or 16384 bytes. The 
+    receive buffer size will be either 4056, 8192, or 16384 bytes.  The
     maximum MTU size is 16114.
 
 RxIntDelay
 Valid Range: 0-65535 (0=off)
-Default Value: 6
-    This value delays the generation of receive interrupts in units of 
-    0.8192 microseconds.  Receive interrupt reduction can improve CPU 
-    efficiency if properly tuned for specific network traffic. Increasing 
-    this value adds extra latency to frame reception and can end up 
-    decreasing the throughput of TCP traffic. If the system is reporting 
-    dropped receives, this value may be set too high, causing the driver to 
+Default Value: 72
+    This value delays the generation of receive interrupts in units of
+    0.8192 microseconds.  Receive interrupt reduction can improve CPU
+    efficiency if properly tuned for specific network traffic.  Increasing
+    this value adds extra latency to frame reception and can end up
+    decreasing the throughput of TCP traffic.  If the system is reporting
+    dropped receives, this value may be set too high, causing the driver to
     run out of available receive descriptors.
 
 TxDescriptors
 Valid Range: 64-4096
 Default Value: 256
     This value is the number of transmit descriptors allocated by the driver.
-    Increasing this value allows the driver to queue more transmits. Each 
+    Increasing this value allows the driver to queue more transmits.  Each
     descriptor is 16 bytes.
 
 XsumRX
@@ -105,51 +162,49 @@ Default Value: 1
     A value of '1' indicates that the driver should enable IP checksum
     offload for received packets (both UDP and TCP) to the adapter hardware.
 
-XsumTX
-Valid Range: 0-1
-Default Value: 1
-    A value of '1' indicates that the driver should enable IP checksum
-    offload for transmitted packets (both UDP and TCP) to the adapter 
-    hardware.
 
 Improving Performance
 =====================
 
-With the Intel PRO/10 GbE adapter, the default Linux configuration will very 
-likely limit the total available throughput artificially.  There is a set of 
-things that when applied together increase the ability of Linux to transmit 
-and receive data.  The following enhancements were originally acquired from
-settings published at http://www.spec.org/web99 for various submitted results 
-using Linux.
+With the 10 Gigabit server adapters, the default Linux configuration will
+very likely limit the total available throughput artificially.  There is a set
+of configuration changes that, when applied together, will increase the ability
+of Linux to transmit and receive data.  The following enhancements were
+originally acquired from settings published at http://www.spec.org/web99/ for
+various submitted results using Linux.
 
-NOTE: These changes are only suggestions, and serve as a starting point for 
-tuning your network performance.
+NOTE: These changes are only suggestions, and serve as a starting point for
+      tuning your network performance.
 
 The changes are made in three major ways, listed in order of greatest effect:
-- Use ifconfig to modify the mtu (maximum transmission unit) and the txqueuelen 
+- Use ifconfig to modify the mtu (maximum transmission unit) and the txqueuelen
   parameter.
 - Use sysctl to modify /proc parameters (essentially kernel tuning)
-- Use setpci to modify the MMRBC field in PCI-X configuration space to increase 
+- Use setpci to modify the MMRBC field in PCI-X configuration space to increase
   transmit burst lengths on the bus.
 
-NOTE: setpci modifies the adapter's configuration registers to allow it to read 
-up to 4k bytes at a time (for transmits).  However, for some systems the 
-behavior after modifying this register may be undefined (possibly errors of some 
-kind). A power-cycle, hard reset or explicitly setting the e6 register back to 
-22 (setpci -d 8086:1048 e6.b=22) may be required to get back to a stable 
-configuration.
+NOTE: setpci modifies the adapter's configuration registers to allow it to read
+up to 4k bytes at a time (for transmits).  However, for some systems the
+behavior after modifying this register may be undefined (possibly errors of
+some kind).  A power-cycle, hard reset or explicitly setting the e6 register
+back to 22 (setpci -d 8086:1a48 e6.b=22) may be required to get back to a
+stable configuration.
 
 - COPY these lines and paste them into ixgb_perf.sh:
 #!/bin/bash
-echo "configuring network performance , edit this file to change the interface"
+echo "configuring network performance , edit this file to change the interface
+or device ID of 10GbE card"
 # set mmrbc to 4k reads, modify only Intel 10GbE device IDs
-setpci -d 8086:1048 e6.b=2e
-# set the MTU (max transmission unit) - it requires your switch and clients to change too!
+# replace 1a48 with appropriate 10GbE device's ID installed on the system,
+# if needed.
+setpci -d 8086:1a48 e6.b=2e
+# set the MTU (max transmission unit) - it requires your switch and clients
+# to change as well.
 # set the txqueuelen
 # your ixgb adapter should be loaded as eth1 for this to work, change if needed
 ifconfig eth1 mtu 9000 txqueuelen 1000 up
-# call the sysctl utility to modify /proc/sys entries 
-sysctl -p ./sysctl_ixgb.conf 
+# call the sysctl utility to modify /proc/sys entries
+sysctl -p ./sysctl_ixgb.conf
 - END ixgb_perf.sh
 
 - COPY these lines and paste them into sysctl_ixgb.conf:
@@ -159,54 +214,220 @@ sysctl -p ./sysctl_ixgb.conf
 # several network benchmark tests, your mileage may vary
 
 ### IPV4 specific settings
-net.ipv4.tcp_timestamps = 0 # turns TCP timestamp support off, default 1, reduces CPU use
-net.ipv4.tcp_sack = 0 # turn SACK support off, default on
-# on systems with a VERY fast bus -> memory interface this is the big gainer 
-net.ipv4.tcp_rmem = 10000000 10000000 10000000 # sets min/default/max TCP read buffer, default 4096 87380 174760
-net.ipv4.tcp_wmem = 10000000 10000000 10000000 # sets min/pressure/max TCP write buffer, default 4096 16384 131072
-net.ipv4.tcp_mem = 10000000 10000000 10000000 # sets min/pressure/max TCP buffer space, default 31744 32256 32768
+# turn TCP timestamp support off, default 1, reduces CPU use
+net.ipv4.tcp_timestamps = 0
+# turn SACK support off, default on
+# on systems with a VERY fast bus -> memory interface this is the big gainer
+net.ipv4.tcp_sack = 0
+# set min/default/max TCP read buffer, default 4096 87380 174760
+net.ipv4.tcp_rmem = 10000000 10000000 10000000
+# set min/pressure/max TCP write buffer, default 4096 16384 131072
+net.ipv4.tcp_wmem = 10000000 10000000 10000000
+# set min/pressure/max TCP buffer space, default 31744 32256 32768
+net.ipv4.tcp_mem = 10000000 10000000 10000000
 
 ### CORE settings (mostly for socket and UDP effect)
-net.core.rmem_max = 524287 # maximum receive socket buffer size, default 131071
-net.core.wmem_max = 524287 # maximum send socket buffer size, default 131071
-net.core.rmem_default = 524287 # default receive socket buffer size, default 65535
-net.core.wmem_default = 524287 # default send socket buffer size, default 65535
-net.core.optmem_max = 524287 # maximum amount of option memory buffers, default 10240
-net.core.netdev_max_backlog = 300000 # number of unprocessed input packets before kernel starts dropping them, default 300
+# set maximum receive socket buffer size, default 131071
+net.core.rmem_max = 524287
+# set maximum send socket buffer size, default 131071
+net.core.wmem_max = 524287
+# set default receive socket buffer size, default 65535
+net.core.rmem_default = 524287
+# set default send socket buffer size, default 65535
+net.core.wmem_default = 524287
+# set maximum amount of option memory buffers, default 10240
+net.core.optmem_max = 524287
+# set number of unprocessed input packets before kernel starts dropping them; default 300
+net.core.netdev_max_backlog = 300000
 - END sysctl_ixgb.conf
 
-Edit the ixgb_perf.sh script if necessary to change eth1 to whatever interface 
-your ixgb driver is using.
+Edit the ixgb_perf.sh script if necessary to change eth1 to whatever interface
+your ixgb driver is using and/or replace '1a48' with appropriate 10GbE device's
+ID installed on the system.
 
-NOTE: Unless these scripts are added to the boot process, these changes will 
-only last only until the next system reboot.
+NOTE: Unless these scripts are added to the boot process, these changes will
+      only last only until the next system reboot.
 
 
 Resolving Slow UDP Traffic
 --------------------------
+If your server does not seem to be able to receive UDP traffic as fast as it
+can receive TCP traffic, it could be because Linux, by default, does not set
+the network stack buffers as large as they need to be to support high UDP
+transfer rates.  One way to alleviate this problem is to allow more memory to
+be used by the IP stack to store incoming data.
 
-If your server does not seem to be able to receive UDP traffic as fast as it 
-can receive TCP traffic, it could be because Linux, by default, does not set 
-the network stack buffers as large as they need to be to support high UDP 
-transfer rates. One way to alleviate this problem is to allow more memory to 
-be used by the IP stack to store incoming data. 
-
-For instance, use the commands: 
+For instance, use the commands:
     sysctl -w net.core.rmem_max=262143
 and
     sysctl -w net.core.rmem_default=262143
-to increase the read buffer memory max and default to 262143 (256k - 1) from 
-defaults of max=131071 (128k - 1) and default=65535 (64k - 1). These variables 
-will increase the amount of memory used by the network stack for receives, and 
+to increase the read buffer memory max and default to 262143 (256k - 1) from
+defaults of max=131071 (128k - 1) and default=65535 (64k - 1).  These variables
+will increase the amount of memory used by the network stack for receives, and
 can be increased significantly more if necessary for your application.
 
+
+Additional Configurations
+=========================
+
+  Configuring the Driver on Different Distributions
+  -------------------------------------------------
+  Configuring a network driver to load properly when the system is started is
+  distribution dependent. Typically, the configuration process involves adding
+  an alias line to /etc/modprobe.conf as well as editing other system startup
+  scripts and/or configuration files.  Many popular Linux distributions ship
+  with tools to make these changes for you.  To learn the proper way to
+  configure a network device for your system, refer to your distribution
+  documentation.  If during this process you are asked for the driver or module
+  name, the name for the Linux Base Driver for the Intel 10GbE Family of
+  Adapters is ixgb.
+
+  Viewing Link Messages
+  ---------------------
+  Link messages will not be displayed to the console if the distribution is
+  restricting system messages. In order to see network driver link messages on
+  your console, set dmesg to eight by entering the following:
+
+       dmesg -n 8
+
+  NOTE: This setting is not saved across reboots.
+
+
+  Jumbo Frames
+  ------------
+  The driver supports Jumbo Frames for all adapters. Jumbo Frames support is
+  enabled by changing the MTU to a value larger than the default of 1500.
+  The maximum value for the MTU is 16114.  Use the ifconfig command to
+  increase the MTU size.  For example:
+
+        ifconfig ethx mtu 9000 up
+
+  The maximum MTU setting for Jumbo Frames is 16114.  This value coincides
+  with the maximum Jumbo Frames size of 16128.
+
+
+  Ethtool
+  -------
+  The driver utilizes the ethtool interface for driver configuration and
+  diagnostics, as well as displaying statistical information.  Ethtool
+  version 1.6 or later is required for this functionality.
+
+  The latest release of ethtool can be found from
+  http://sourceforge.net/projects/gkernel
+
+  NOTE: Ethtool 1.6 only supports a limited set of ethtool options. Support
+        for a more complete ethtool feature set can be enabled by upgrading
+        to the latest version.
+
+
+  NAPI
+  ----
+
+  NAPI (Rx polling mode) is supported in the ixgb driver.  NAPI is enabled
+  or disabled based on the configuration of the kernel.  see CONFIG_IXGB_NAPI
+
+  See www.cyberus.ca/~hadi/usenix-paper.tgz for more information on NAPI.
+
+
+Known Issues/Troubleshooting
+============================
+
+  NOTE: After installing the driver, if your Intel Network Connection is not
+  working, verify in the "In This Release" section of the readme that you have
+  installed the correct driver.
+
+  Intel(R) PRO/10GbE CX4 Server Adapter Cable Interoperability Issue with
+  Fujitsu XENPAK Module in SmartBits Chassis
+  ---------------------------------------------------------------------
+  Excessive CRC errors may be observed if the Intel(R) PRO/10GbE CX4
+  Server adapter is connected to a Fujitsu XENPAK CX4 module in a SmartBits
+  chassis using 15 m/24AWG cable assemblies manufactured by Fujitsu or Leoni.
+  The CRC errors may be received either by the Intel(R) PRO/10GbE CX4
+  Server adapter or the SmartBits. If this situation occurs using a different
+  cable assembly may resolve the issue.
+
+  CX4 Server Adapter Cable Interoperability Issues with HP Procurve 3400cl
+  Switch Port
+  ------------------------------------------------------------------------
+  Excessive CRC errors may be observed if the Intel(R) PRO/10GbE CX4 Server
+  adapter is connected to an HP Procurve 3400cl switch port using short cables
+  (1 m or shorter). If this situation occurs, using a longer cable may resolve
+  the issue.
+
+  Excessive CRC errors may be observed using Fujitsu 24AWG cable assemblies that
+  Are 10 m or longer or where using a Leoni 15 m/24AWG cable assembly. The CRC
+  errors may be received either by the CX4 Server adapter or at the switch. If
+  this situation occurs, using a different cable assembly may resolve the issue.
+
+
+  Jumbo Frames System Requirement
+  -------------------------------
+  Memory allocation failures have been observed on Linux systems with 64 MB
+  of RAM or less that are running Jumbo Frames.  If you are using Jumbo
+  Frames, your system may require more than the advertised minimum
+  requirement of 64 MB of system memory.
+
+
+  Performance Degradation with Jumbo Frames
+  -----------------------------------------
+  Degradation in throughput performance may be observed in some Jumbo frames
+  environments.  If this is observed, increasing the application's socket buffer
+  size and/or increasing the /proc/sys/net/ipv4/tcp_*mem entry values may help.
+  See the specific application manual and /usr/src/linux*/Documentation/
+  networking/ip-sysctl.txt for more details.
+
+
+  Allocating Rx Buffers when Using Jumbo Frames
+  ---------------------------------------------
+  Allocating Rx buffers when using Jumbo Frames on 2.6.x kernels may fail if
+  the available memory is heavily fragmented. This issue may be seen with PCI-X
+  adapters or with packet split disabled. This can be reduced or eliminated
+  by changing the amount of available memory for receive buffer allocation, by
+  increasing /proc/sys/vm/min_free_kbytes.
+
+
+  Multiple Interfaces on Same Ethernet Broadcast Network
+  ------------------------------------------------------
+  Due to the default ARP behavior on Linux, it is not possible to have
+  one system on two IP networks in the same Ethernet broadcast domain
+  (non-partitioned switch) behave as expected.  All Ethernet interfaces
+  will respond to IP traffic for any IP address assigned to the system.
+  This results in unbalanced receive traffic.
+
+  If you have multiple interfaces in a server, do either of the following:
+
+  - Turn on ARP filtering by entering:
+      echo 1 > /proc/sys/net/ipv4/conf/all/arp_filter
+
+  - Install the interfaces in separate broadcast domains - either in
+    different switches or in a switch partitioned to VLANs.
+
+
+  UDP Stress Test Dropped Packet Issue
+  --------------------------------------
+  Under small packets UDP stress test with 10GbE driver, the Linux system
+  may drop UDP packets due to the fullness of socket buffers. You may want
+  to change the driver's Flow Control variables to the minimum value for
+  controlling packet reception.
+
+
+  Tx Hangs Possible Under Stress
+  ------------------------------
+  Under stress conditions, if TX hangs occur, turning off TSO
+  "ethtool -K eth0 tso off" may resolve the problem.
+
+
 Support
 =======
 
-For general information and support, go to the Intel support website at:
+For general information, go to the Intel support website at:
 
     http://support.intel.com
 
+or the Intel Wired Networking project hosted by Sourceforge at:
+
+    http://sourceforge.net/projects/e1000
+
 If an issue is identified with the released source code on the supported
-kernel with a supported adapter, email the specific information related to 
-the issue to linux.nics@intel.com.
+kernel with a supported adapter, email the specific information related
+to the issue to e1000-devel@lists.sf.net

Documentation/networking/mac80211_hwsim/README

@@ -0,0 +1,67 @@
+mac80211_hwsim - software simulator of 802.11 radio(s) for mac80211
+Copyright (c) 2008, Jouni Malinen <j@w1.fi>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License version 2 as
+published by the Free Software Foundation.
+
+
+Introduction
+
+mac80211_hwsim is a Linux kernel module that can be used to simulate
+arbitrary number of IEEE 802.11 radios for mac80211. It can be used to
+test most of the mac80211 functionality and user space tools (e.g.,
+hostapd and wpa_supplicant) in a way that matches very closely with
+the normal case of using real WLAN hardware. From the mac80211 view
+point, mac80211_hwsim is yet another hardware driver, i.e., no changes
+to mac80211 are needed to use this testing tool.
+
+The main goal for mac80211_hwsim is to make it easier for developers
+to test their code and work with new features to mac80211, hostapd,
+and wpa_supplicant. The simulated radios do not have the limitations
+of real hardware, so it is easy to generate an arbitrary test setup
+and always reproduce the same setup for future tests. In addition,
+since all radio operation is simulated, any channel can be used in
+tests regardless of regulatory rules.
+
+mac80211_hwsim kernel module has a parameter 'radios' that can be used
+to select how many radios are simulated (default 2). This allows
+configuration of both very simply setups (e.g., just a single access
+point and a station) or large scale tests (multiple access points with
+hundreds of stations).
+
+mac80211_hwsim works by tracking the current channel of each virtual
+radio and copying all transmitted frames to all other radios that are
+currently enabled and on the same channel as the transmitting
+radio. Software encryption in mac80211 is used so that the frames are
+actually encrypted over the virtual air interface to allow more
+complete testing of encryption.
+
+A global monitoring netdev, hwsim#, is created independent of
+mac80211. This interface can be used to monitor all transmitted frames
+regardless of channel.
+
+
+Simple example
+
+This example shows how to use mac80211_hwsim to simulate two radios:
+one to act as an access point and the other as a station that
+associates with the AP. hostapd and wpa_supplicant are used to take
+care of WPA2-PSK authentication. In addition, hostapd is also
+processing access point side of association.
+
+Please note that the current Linux kernel does not enable AP mode, so a
+simple patch is needed to enable AP mode selection:
+http://johannes.sipsolutions.net/patches/kernel/all/LATEST/006-allow-ap-vlan-modes.patch
+
+
+# Build mac80211_hwsim as part of kernel configuration
+
+# Load the module
+modprobe mac80211_hwsim
+
+# Run hostapd (AP) for wlan0
+hostapd hostapd.conf
+
+# Run wpa_supplicant (station) for wlan1
+wpa_supplicant -Dwext -iwlan1 -c wpa_supplicant.conf

Documentation/networking/mac80211_hwsim/hostapd.conf

@@ -0,0 +1,11 @@
+interface=wlan0
+driver=nl80211
+
+hw_mode=g
+channel=1
+ssid=mac80211 test
+
+wpa=2
+wpa_key_mgmt=WPA-PSK
+wpa_pairwise=CCMP
+wpa_passphrase=12345678

Documentation/networking/mac80211_hwsim/wpa_supplicant.conf

@@ -0,0 +1,10 @@
+ctrl_interface=/var/run/wpa_supplicant
+
+network={
+	ssid="mac80211 test"
+	psk="12345678"
+	key_mgmt=WPA-PSK
+	proto=WPA2
+	pairwise=CCMP
+	group=CCMP
+}

Documentation/networking/multiqueue.txt

@@ -3,19 +3,11 @@
 		===========================================
 
 Section 1: Base driver requirements for implementing multiqueue support
-Section 2: Qdisc support for multiqueue devices
-Section 3: Brief howto using PRIO or RR for multiqueue devices
-
 
 Intro: Kernel support for multiqueue devices
 ---------------------------------------------------------
 
-Kernel support for multiqueue devices is only an API that is presented to the
-netdevice layer for base drivers to implement.  This feature is part of the
-core networking stack, and all network devices will be running on the
-multiqueue-aware stack.  If a base driver only has one queue, then these
-changes are transparent to that driver.
-
+Kernel support for multiqueue devices is always present.
 
 Section 1: Base driver requirements for implementing multiqueue support
 -----------------------------------------------------------------------
@@ -32,84 +24,4 @@ netif_{start|stop|wake}_subqueue() functions to manage each queue while the
 device is still operational.  netdev->queue_lock is still used when the device
 comes online or when it's completely shut down (unregister_netdev(), etc.).
 
-Finally, the base driver should indicate that it is a multiqueue device.  The
-feature flag NETIF_F_MULTI_QUEUE should be added to the netdev->features
-bitmap on device initialization.  Below is an example from e1000:
-
-#ifdef CONFIG_E1000_MQ
-	if ( (adapter->hw.mac.type == e1000_82571) ||
-	     (adapter->hw.mac.type == e1000_82572) ||
-	     (adapter->hw.mac.type == e1000_80003es2lan))
-		netdev->features |= NETIF_F_MULTI_QUEUE;
-#endif
-
-
-Section 2: Qdisc support for multiqueue devices
------------------------------------------------
-
-Currently two qdiscs support multiqueue devices.  A new round-robin qdisc,
-sch_rr, and sch_prio. The qdisc is responsible for classifying the skb's to
-bands and queues, and will store the queue mapping into skb->queue_mapping.
-Use this field in the base driver to determine which queue to send the skb
-to.
-
-sch_rr has been added for hardware that doesn't want scheduling policies from
-software, so it's a straight round-robin qdisc.  It uses the same syntax and
-classification priomap that sch_prio uses, so it should be intuitive to
-configure for people who've used sch_prio.
-
-In order to utilitize the multiqueue features of the qdiscs, the network
-device layer needs to enable multiple queue support.  This can be done by
-selecting NETDEVICES_MULTIQUEUE under Drivers.
-
-The PRIO qdisc naturally plugs into a multiqueue device.  If
-NETDEVICES_MULTIQUEUE is selected, then on qdisc load, the number of
-bands requested is compared to the number of queues on the hardware.  If they
-are equal, it sets a one-to-one mapping up between the queues and bands.  If
-they're not equal, it will not load the qdisc.  This is the same behavior
-for RR.  Once the association is made, any skb that is classified will have
-skb->queue_mapping set, which will allow the driver to properly queue skb's
-to multiple queues.
-
-
-Section 3: Brief howto using PRIO and RR for multiqueue devices
----------------------------------------------------------------
-
-The userspace command 'tc,' part of the iproute2 package, is used to configure
-qdiscs.  To add the PRIO qdisc to your network device, assuming the device is
-called eth0, run the following command:
-
-# tc qdisc add dev eth0 root handle 1: prio bands 4 multiqueue
-
-This will create 4 bands, 0 being highest priority, and associate those bands
-to the queues on your NIC.  Assuming eth0 has 4 Tx queues, the band mapping
-would look like:
-
-band 0 => queue 0
-band 1 => queue 1
-band 2 => queue 2
-band 3 => queue 3
-
-Traffic will begin flowing through each queue if your TOS values are assigning
-traffic across the various bands.  For example, ssh traffic will always try to
-go out band 0 based on TOS -> Linux priority conversion (realtime traffic),
-so it will be sent out queue 0.  ICMP traffic (pings) fall into the "normal"
-traffic classification, which is band 1.  Therefore pings will be send out
-queue 1 on the NIC.
-
-Note the use of the multiqueue keyword.  This is only in versions of iproute2
-that support multiqueue networking devices; if this is omitted when loading
-a qdisc onto a multiqueue device, the qdisc will load and operate the same
-if it were loaded onto a single-queue device (i.e. - sends all traffic to
-queue 0).
-
-Another alternative to multiqueue band allocation can be done by using the
-multiqueue option and specify 0 bands.  If this is the case, the qdisc will
-allocate the number of bands to equal the number of queues that the device
-reports, and bring the qdisc online.
-
-The behavior of tc filters remains the same, where it will override TOS priority
-classification.
-
-
 Author: Peter P. Waskiewicz Jr. <peter.p.waskiewicz.jr@intel.com>

Documentation/networking/s2io.txt

@@ -52,13 +52,10 @@ d. MSI/MSI-X. Can be enabled on platforms which support this feature
 (IA64, Xeon) resulting in noticeable performance improvement(upto 7%
 on certain platforms).
 
-e. NAPI. Compile-time option(CONFIG_S2IO_NAPI) for better Rx interrupt 
-moderation.
-
-f. Statistics. Comprehensive MAC-level and software statistics displayed
+e. Statistics. Comprehensive MAC-level and software statistics displayed
 using "ethtool -S" option.
 
-g. Multi-FIFO/Ring. Supports up to 8 transmit queues and receive rings, 
+f. Multi-FIFO/Ring. Supports up to 8 transmit queues and receive rings,
 with multiple steering options.
 
 4.  Command line parameters
@@ -83,9 +80,9 @@ Valid range: Limited by memory on system
 Default: 30 
 
 e. intr_type
-Specifies interrupt type. Possible values 1(INTA), 2(MSI), 3(MSI-X)
-Valid range: 1-3
-Default: 1 
+Specifies interrupt type. Possible values 0(INTA), 2(MSI-X)
+Valid values: 0, 2
+Default: 2
 
 5.  Performance suggestions
 General:

Documentation/nmi_watchdog.txt

@@ -10,7 +10,7 @@ us to generate 'watchdog NMI interrupts'.  (NMI: Non Maskable Interrupt
 which get executed even if the system is otherwise locked up hard).
 This can be used to debug hard kernel lockups.  By executing periodic
 NMI interrupts, the kernel can monitor whether any CPU has locked up,
-and print out debugging messages if so.  
+and print out debugging messages if so.
 
 In order to use the NMI watchdog, you need to have APIC support in your
 kernel. For SMP kernels, APIC support gets compiled in automatically. For
@@ -22,8 +22,7 @@ CONFIG_X86_UP_IOAPIC is for uniprocessor with an IO-APIC. [Note: certain
 kernel debugging options, such as Kernel Stack Meter or Kernel Tracer,
 may implicitly disable the NMI watchdog.]
 
-For x86-64, the needed APIC is always compiled in, and the NMI watchdog is
-always enabled with I/O-APIC mode (nmi_watchdog=1).
+For x86-64, the needed APIC is always compiled in.
 
 Using local APIC (nmi_watchdog=2) needs the first performance register, so
 you can't use it for other purposes (such as high precision performance
@@ -63,16 +62,15 @@ when the system is idle), but if your system locks up on anything but the
 "hlt", then you are out of luck -- the event will not happen at all and the
 watchdog won't trigger. This is a shortcoming of the local APIC watchdog
 -- unfortunately there is no "clock ticks" event that would work all the
-time. The I/O APIC watchdog is driven externally and has no such shortcoming.  
+time. The I/O APIC watchdog is driven externally and has no such shortcoming.
 But its NMI frequency is much higher, resulting in a more significant hit
 to the overall system performance.
 
-NOTE: starting with 2.4.2-ac18 the NMI-oopser is disabled by default,
-you have to enable it with a boot time parameter.  Prior to 2.4.2-ac18
-the NMI-oopser is enabled unconditionally on x86 SMP boxes.
+On x86 nmi_watchdog is disabled by default so you have to enable it with
+a boot time parameter.
 
-On x86-64 the NMI oopser is on by default. On 64bit Intel CPUs
-it uses IO-APIC by default and on AMD it uses local APIC.
+NOTE: In kernels prior to 2.4.2-ac18 the NMI-oopser is enabled unconditionally
+on x86 SMP boxes.
 
 [ feel free to send bug reports, suggestions and patches to
   Ingo Molnar <mingo@redhat.com> or the Linux SMP mailing

Documentation/powerpc/bootwrapper.txt

@@ -0,0 +1,141 @@
+The PowerPC boot wrapper
+------------------------
+Copyright (C) Secret Lab Technologies Ltd.
+
+PowerPC image targets compresses and wraps the kernel image (vmlinux) with
+a boot wrapper to make it usable by the system firmware.  There is no
+standard PowerPC firmware interface, so the boot wrapper is designed to
+be adaptable for each kind of image that needs to be built.
+
+The boot wrapper can be found in the arch/powerpc/boot/ directory.  The
+Makefile in that directory has targets for all the available image types.
+The different image types are used to support all of the various firmware
+interfaces found on PowerPC platforms.  OpenFirmware is the most commonly
+used firmware type on general purpose PowerPC systems from Apple, IBM and
+others.  U-Boot is typically found on embedded PowerPC hardware, but there
+are a handful of other firmware implementations which are also popular.  Each
+firmware interface requires a different image format.
+
+The boot wrapper is built from the makefile in arch/powerpc/boot/Makefile and
+it uses the wrapper script (arch/powerpc/boot/wrapper) to generate target
+image.  The details of the build system is discussed in the next section.
+Currently, the following image format targets exist:
+
+   cuImage.%:		Backwards compatible uImage for older version of
+			U-Boot (for versions that don't understand the device
+			tree).  This image embeds a device tree blob inside
+			the image.  The boot wrapper, kernel and device tree
+			are all embedded inside the U-Boot uImage file format
+			with boot wrapper code that extracts data from the old
+			bd_info structure and loads the data into the device
+			tree before jumping into the kernel.
+			  Because of the series of #ifdefs found in the
+			bd_info structure used in the old U-Boot interfaces,
+			cuImages are platform specific.  Each specific
+			U-Boot platform has a different platform init file
+			which populates the embedded device tree with data
+			from the platform specific bd_info file.  The platform
+			specific cuImage platform init code can be found in
+			arch/powerpc/boot/cuboot.*.c.  Selection of the correct
+			cuImage init code for a specific board can be found in
+			the wrapper structure.
+   dtbImage.%:		Similar to zImage, except device tree blob is embedded
+			inside the image instead of provided by firmware.  The
+			output image file can be either an elf file or a flat
+			binary depending on the platform.
+			  dtbImages are used on systems which do not have an
+			interface for passing a device tree directly.
+			dtbImages are similar to simpleImages except that
+			dtbImages have platform specific code for extracting
+			data from the board firmware, but simpleImages do not
+			talk to the firmware at all.
+			  PlayStation 3 support uses dtbImage.  So do Embedded
+			Planet boards using the PlanetCore firmware.  Board
+			specific initialization code is typically found in a
+			file named arch/powerpc/boot/<platform>.c; but this
+			can be overridden by the wrapper script.
+   simpleImage.%:	Firmware independent compressed image that does not
+			depend on any particular firmware interface and embeds
+			a device tree blob.  This image is a flat binary that
+			can be loaded to any location in RAM and jumped to.
+			Firmware cannot pass any configuration data to the
+			kernel with this image type and it depends entirely on
+			the embedded device tree for all information.
+			  The simpleImage is useful for booting systems with
+			an unknown firmware interface or for booting from
+			a debugger when no firmware is present (such as on
+			the Xilinx Virtex platform).  The only assumption that
+			simpleImage makes is that RAM is correctly initialized
+			and that the MMU is either off or has RAM mapped to
+			base address 0.
+			  simpleImage also supports inserting special platform
+			specific initialization code to the start of the bootup
+			sequence.  The virtex405 platform uses this feature to
+			ensure that the cache is invalidated before caching
+			is enabled.  Platform specific initialization code is
+			added as part of the wrapper script and is keyed on
+			the image target name.  For example, all
+			simpleImage.virtex405-* targets will add the
+			virtex405-head.S initialization code (This also means
+			that the dts file for virtex405 targets should be
+			named (virtex405-<board>.dts).  Search the wrapper
+			script for 'virtex405' and see the file
+			arch/powerpc/boot/virtex405-head.S for details.
+   treeImage.%;		Image format for used with OpenBIOS firmware found
+			on some ppc4xx hardware.  This image embeds a device
+			tree blob inside the image.
+   uImage:		Native image format used by U-Boot.  The uImage target
+			does not add any boot code.  It just wraps a compressed
+			vmlinux in the uImage data structure.  This image
+			requires a version of U-Boot that is able to pass
+			a device tree to the kernel at boot.  If using an older
+			version of U-Boot, then you need to use a cuImage
+			instead.
+   zImage.%:		Image format which does not embed a device tree.
+			Used by OpenFirmware and other firmware interfaces
+			which are able to supply a device tree.  This image
+			expects firmware to provide the device tree at boot.
+			Typically, if you have general purpose PowerPC
+			hardware then you want this image format.
+
+Image types which embed a device tree blob (simpleImage, dtbImage, treeImage,
+and cuImage) all generate the device tree blob from a file in the
+arch/powerpc/boot/dts/ directory.  The Makefile selects the correct device
+tree source based on the name of the target.  Therefore, if the kernel is
+built with 'make treeImage.walnut simpleImage.virtex405-ml403', then the
+build system will use arch/powerpc/boot/dts/walnut.dts to build
+treeImage.walnut and arch/powerpc/boot/dts/virtex405-ml403.dts to build
+the simpleImage.virtex405-ml403.
+
+Two special targets called 'zImage' and 'zImage.initrd' also exist.  These
+targets build all the default images as selected by the kernel configuration.
+Default images are selected by the boot wrapper Makefile
+(arch/powerpc/boot/Makefile) by adding targets to the $image-y variable.  Look
+at the Makefile to see which default image targets are available.
+
+How it is built
+---------------
+arch/powerpc is designed to support multiplatform kernels, which means
+that a single vmlinux image can be booted on many different target boards.
+It also means that the boot wrapper must be able to wrap for many kinds of
+images on a single build.  The design decision was made to not use any
+conditional compilation code (#ifdef, etc) in the boot wrapper source code.
+All of the boot wrapper pieces are buildable at any time regardless of the
+kernel configuration.  Building all the wrapper bits on every kernel build
+also ensures that obscure parts of the wrapper are at the very least compile
+tested in a large variety of environments.
+
+The wrapper is adapted for different image types at link time by linking in
+just the wrapper bits that are appropriate for the image type.  The 'wrapper
+script' (found in arch/powerpc/boot/wrapper) is called by the Makefile and
+is responsible for selecting the correct wrapper bits for the image type.
+The arguments are well documented in the script's comment block, so they
+are not repeated here.  However, it is worth mentioning that the script
+uses the -p (platform) argument as the main method of deciding which wrapper
+bits to compile in.  Look for the large 'case "$platform" in' block in the
+middle of the script.  This is also the place where platform specific fixups
+can be selected by changing the link order.
+
+In particular, care should be taken when working with cuImages.  cuImage
+wrapper bits are very board specific and care should be taken to make sure
+the target you are trying to build is supported by the wrapper bits.

Documentation/powerpc/dts-bindings/fsl/board.txt

@@ -0,0 +1,29 @@
+* Board Control and Status (BCSR)
+
+Required properties:
+
+ - device_type : Should be "board-control"
+ - reg : Offset and length of the register set for the device
+
+Example:
+
+	bcsr@f8000000 {
+		device_type = "board-control";
+		reg = <f8000000 8000>;
+	};
+
+* Freescale on board FPGA
+
+This is the memory-mapped registers for on board FPGA.
+
+Required properities:
+- compatible : should be "fsl,fpga-pixis".
+- reg : should contain the address and the lenght of the FPPGA register
+  set.
+
+Example (MPC8610HPCD):
+
+	board-control@e8000000 {
+		compatible = "fsl,fpga-pixis";
+		reg = <0xe8000000 32>;
+	};

Documentation/powerpc/dts-bindings/fsl/cpm_qe/cpm.txt

@@ -0,0 +1,67 @@
+* Freescale Communications Processor Module
+
+NOTE: This is an interim binding, and will likely change slightly,
+as more devices are supported.  The QE bindings especially are
+incomplete.
+
+* Root CPM node
+
+Properties:
+- compatible : "fsl,cpm1", "fsl,cpm2", or "fsl,qe".
+- reg : A 48-byte region beginning with CPCR.
+
+Example:
+     cpm@119c0 {
+	#address-cells = <1>;
+	#size-cells = <1>;
+	#interrupt-cells = <2>;
+	compatible = "fsl,mpc8272-cpm", "fsl,cpm2";
+	reg = <119c0 30>;
+     }
+
+* Properties common to mulitple CPM/QE devices
+
+- fsl,cpm-command : This value is ORed with the opcode and command flag
+                    to specify the device on which a CPM command operates.
+
+- fsl,cpm-brg : Indicates which baud rate generator the device
+                is associated with.  If absent, an unused BRG
+                should be dynamically allocated.  If zero, the
+                device uses an external clock rather than a BRG.
+
+- reg : Unless otherwise specified, the first resource represents the
+        scc/fcc/ucc registers, and the second represents the device's
+        parameter RAM region (if it has one).
+
+* Multi-User RAM (MURAM)
+
+The multi-user/dual-ported RAM is expressed as a bus under the CPM node.
+
+Ranges must be set up subject to the following restrictions:
+
+- Children's reg nodes must be offsets from the start of all muram, even
+  if the user-data area does not begin at zero.
+- If multiple range entries are used, the difference between the parent
+  address and the child address must be the same in all, so that a single
+  mapping can cover them all while maintaining the ability to determine
+  CPM-side offsets with pointer subtraction.  It is recommended that
+  multiple range entries not be used.
+- A child address of zero must be translatable, even if no reg resources
+  contain it.
+
+A child "data" node must exist, compatible with "fsl,cpm-muram-data", to
+indicate the portion of muram that is usable by the OS for arbitrary
+purposes.  The data node may have an arbitrary number of reg resources,
+all of which contribute to the allocatable muram pool.
+
+Example, based on mpc8272:
+	muram@0 {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges = <0 0 10000>;
+
+		data@0 {
+			compatible = "fsl,cpm-muram-data";
+			reg = <0 2000 9800 800>;
+		};
+	};

Documentation/powerpc/dts-bindings/fsl/cpm_qe/cpm/brg.txt

@@ -0,0 +1,21 @@
+* Baud Rate Generators
+
+Currently defined compatibles:
+fsl,cpm-brg
+fsl,cpm1-brg
+fsl,cpm2-brg
+
+Properties:
+- reg : There may be an arbitrary number of reg resources; BRG
+  numbers are assigned to these in order.
+- clock-frequency : Specifies the base frequency driving
+  the BRG.
+
+Example:
+	brg@119f0 {
+		compatible = "fsl,mpc8272-brg",
+			     "fsl,cpm2-brg",
+			     "fsl,cpm-brg";
+		reg = <119f0 10 115f0 10>;
+		clock-frequency = <d#25000000>;
+	};

Documentation/powerpc/dts-bindings/fsl/cpm_qe/cpm/i2c.txt

@@ -0,0 +1,41 @@
+* I2C
+
+The I2C controller is expressed as a bus under the CPM node.
+
+Properties:
+- compatible : "fsl,cpm1-i2c", "fsl,cpm2-i2c"
+- reg : On CPM2 devices, the second resource doesn't specify the I2C
+  Parameter RAM itself, but the I2C_BASE field of the CPM2 Parameter RAM
+  (typically 0x8afc 0x2).
+- #address-cells : Should be one. The cell is the i2c device address with
+  the r/w bit set to zero.
+- #size-cells : Should be zero.
+- clock-frequency : Can be used to set the i2c clock frequency. If
+  unspecified, a default frequency of 60kHz is being used.
+The following two properties are deprecated. They are only used by legacy
+i2c drivers to find the bus to probe:
+- linux,i2c-index : Can be used to hard code an i2c bus number. By default,
+  the bus number is dynamically assigned by the i2c core.
+- linux,i2c-class : Can be used to override the i2c class. The class is used
+  by legacy i2c device drivers to find a bus in a specific context like
+  system management, video or sound. By default, I2C_CLASS_HWMON (1) is
+  being used. The definition of the classes can be found in
+  include/i2c/i2c.h
+
+Example, based on mpc823:
+
+	i2c@860 {
+		compatible = "fsl,mpc823-i2c",
+			     "fsl,cpm1-i2c";
+		reg = <0x860 0x20 0x3c80 0x30>;
+		interrupts = <16>;
+		interrupt-parent = <&CPM_PIC>;
+		fsl,cpm-command = <0x10>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		rtc@68 {
+			compatible = "dallas,ds1307";
+			reg = <0x68>;
+		};
+	};

Documentation/powerpc/dts-bindings/fsl/cpm_qe/cpm/pic.txt

@@ -0,0 +1,18 @@
+* Interrupt Controllers
+
+Currently defined compatibles:
+- fsl,cpm1-pic
+  - only one interrupt cell
+- fsl,pq1-pic
+- fsl,cpm2-pic
+  - second interrupt cell is level/sense:
+    - 2 is falling edge
+    - 8 is active low
+
+Example:
+	interrupt-controller@10c00 {
+		#interrupt-cells = <2>;
+		interrupt-controller;
+		reg = <10c00 80>;
+		compatible = "mpc8272-pic", "fsl,cpm2-pic";
+	};

Documentation/powerpc/dts-bindings/fsl/cpm_qe/cpm/usb.txt

@@ -0,0 +1,15 @@
+* USB (Universal Serial Bus Controller)
+
+Properties:
+- compatible : "fsl,cpm1-usb", "fsl,cpm2-usb", "fsl,qe-usb"
+
+Example:
+	usb@11bc0 {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		compatible = "fsl,cpm2-usb";
+		reg = <11b60 18 8b00 100>;
+		interrupts = <b 8>;
+		interrupt-parent = <&PIC>;
+		fsl,cpm-command = <2e600000>;
+	};

Documentation/powerpc/dts-bindings/fsl/cpm_qe/network.txt

@@ -0,0 +1,45 @@
+* Network
+
+Currently defined compatibles:
+- fsl,cpm1-scc-enet
+- fsl,cpm2-scc-enet
+- fsl,cpm1-fec-enet
+- fsl,cpm2-fcc-enet (third resource is GFEMR)
+- fsl,qe-enet
+
+Example:
+
+	ethernet@11300 {
+		device_type = "network";
+		compatible = "fsl,mpc8272-fcc-enet",
+			     "fsl,cpm2-fcc-enet";
+		reg = <11300 20 8400 100 11390 1>;
+		local-mac-address = [ 00 00 00 00 00 00 ];
+		interrupts = <20 8>;
+		interrupt-parent = <&PIC>;
+		phy-handle = <&PHY0>;
+		fsl,cpm-command = <12000300>;
+	};
+
+* MDIO
+
+Currently defined compatibles:
+fsl,pq1-fec-mdio (reg is same as first resource of FEC device)
+fsl,cpm2-mdio-bitbang (reg is port C registers)
+
+Properties for fsl,cpm2-mdio-bitbang:
+fsl,mdio-pin : pin of port C controlling mdio data
+fsl,mdc-pin : pin of port C controlling mdio clock
+
+Example:
+	mdio@10d40 {
+		device_type = "mdio";
+		compatible = "fsl,mpc8272ads-mdio-bitbang",
+			     "fsl,mpc8272-mdio-bitbang",
+			     "fsl,cpm2-mdio-bitbang";
+		reg = <10d40 14>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+		fsl,mdio-pin = <12>;
+		fsl,mdc-pin = <13>;
+	};

Documentation/powerpc/dts-bindings/fsl/cpm_qe/qe.txt

@@ -0,0 +1,58 @@
+* Freescale QUICC Engine module (QE)
+This represents qe module that is installed on PowerQUICC II Pro.
+
+NOTE:  This is an interim binding; it should be updated to fit
+in with the CPM binding later in this document.
+
+Basically, it is a bus of devices, that could act more or less
+as a complete entity (UCC, USB etc ). All of them should be siblings on
+the "root" qe node, using the common properties from there.
+The description below applies to the qe of MPC8360 and
+more nodes and properties would be extended in the future.
+
+i) Root QE device
+
+Required properties:
+- compatible : should be "fsl,qe";
+- model : precise model of the QE, Can be "QE", "CPM", or "CPM2"
+- reg : offset and length of the device registers.
+- bus-frequency : the clock frequency for QUICC Engine.
+
+Recommended properties
+- brg-frequency : the internal clock source frequency for baud-rate
+  generators in Hz.
+
+Example:
+     qe@e0100000 {
+	#address-cells = <1>;
+	#size-cells = <1>;
+	#interrupt-cells = <2>;
+	compatible = "fsl,qe";
+	ranges = <0 e0100000 00100000>;
+	reg = <e0100000 480>;
+	brg-frequency = <0>;
+	bus-frequency = <179A7B00>;
+     }
+
+* Multi-User RAM (MURAM)
+
+Required properties:
+- compatible : should be "fsl,qe-muram", "fsl,cpm-muram".
+- mode : the could be "host" or "slave".
+- ranges : Should be defined as specified in 1) to describe the
+   translation of MURAM addresses.
+- data-only : sub-node which defines the address area under MURAM
+   bus that can be allocated as data/parameter
+
+Example:
+
+     muram@10000 {
+	compatible = "fsl,qe-muram", "fsl,cpm-muram";
+	ranges = <0 00010000 0000c000>;
+
+	data-only@0{
+		compatible = "fsl,qe-muram-data",
+			     "fsl,cpm-muram-data";
+		reg = <0 c000>;
+	};
+     };

Documentation/powerpc/dts-bindings/fsl/cpm_qe/qe/firmware.txt

@@ -0,0 +1,24 @@
+* Uploaded QE firmware
+
+      If a new firwmare has been uploaded to the QE (usually by the
+      boot loader), then a 'firmware' child node should be added to the QE
+      node.  This node provides information on the uploaded firmware that
+      device drivers may need.
+
+      Required properties:
+      - id: The string name of the firmware.  This is taken from the 'id'
+            member of the qe_firmware structure of the uploaded firmware.
+            Device drivers can search this string to determine if the
+            firmware they want is already present.
+      - extended-modes: The Extended Modes bitfield, taken from the
+		   firmware binary.  It is a 64-bit number represented
+		   as an array of two 32-bit numbers.
+      - virtual-traps: The virtual traps, taken from the firmware binary.
+		  It is an array of 8 32-bit numbers.
+
+Example:
+	firmware {
+		id = "Soft-UART";
+		extended-modes = <0 0>;
+		virtual-traps = <0 0 0 0 0 0 0 0>;
+	};

Documentation/powerpc/dts-bindings/fsl/cpm_qe/qe/par_io.txt

@@ -0,0 +1,51 @@
+* Parallel I/O Ports
+
+This node configures Parallel I/O ports for CPUs with QE support.
+The node should reside in the "soc" node of the tree.  For each
+device that using parallel I/O ports, a child node should be created.
+See the definition of the Pin configuration nodes below for more
+information.
+
+Required properties:
+- device_type : should be "par_io".
+- reg : offset to the register set and its length.
+- num-ports : number of Parallel I/O ports
+
+Example:
+par_io@1400 {
+	reg = <1400 100>;
+	#address-cells = <1>;
+	#size-cells = <0>;
+	device_type = "par_io";
+	num-ports = <7>;
+	ucc_pin@01 {
+		......
+	};
+
+Note that "par_io" nodes are obsolete, and should not be used for
+the new device trees. Instead, each Par I/O bank should be represented
+via its own gpio-controller node:
+
+Required properties:
+- #gpio-cells : should be "2".
+- compatible : should be "fsl,<chip>-qe-pario-bank",
+  "fsl,mpc8323-qe-pario-bank".
+- reg : offset to the register set and its length.
+- gpio-controller : node to identify gpio controllers.
+
+Example:
+	qe_pio_a: gpio-controller@1400 {
+		#gpio-cells = <2>;
+		compatible = "fsl,mpc8360-qe-pario-bank",
+		"fsl,mpc8323-qe-pario-bank";
+		reg = <0x1400 0x18>;
+		gpio-controller;
+	  };
+
+	qe_pio_e: gpio-controller@1460 {
+		#gpio-cells = <2>;
+		compatible = "fsl,mpc8360-qe-pario-bank",
+			     "fsl,mpc8323-qe-pario-bank";
+		reg = <0x1460 0x18>;
+		gpio-controller;
+	  };

Documentation/powerpc/dts-bindings/fsl/cpm_qe/qe/pincfg.txt

@@ -0,0 +1,60 @@
+* Pin configuration nodes
+
+Required properties:
+- linux,phandle : phandle of this node; likely referenced by a QE
+  device.
+- pio-map : array of pin configurations.  Each pin is defined by 6
+  integers.  The six numbers are respectively: port, pin, dir,
+  open_drain, assignment, has_irq.
+  - port : port number of the pin; 0-6 represent port A-G in UM.
+  - pin : pin number in the port.
+  - dir : direction of the pin, should encode as follows:
+
+     0 = The pin is disabled
+     1 = The pin is an output
+     2 = The pin is an input
+     3 = The pin is I/O
+
+  - open_drain : indicates the pin is normal or wired-OR:
+
+     0 = The pin is actively driven as an output
+     1 = The pin is an open-drain driver. As an output, the pin is
+         driven active-low, otherwise it is three-stated.
+
+  - assignment : function number of the pin according to the Pin Assignment
+    tables in User Manual.  Each pin can have up to 4 possible functions in
+    QE and two options for CPM.
+  - has_irq : indicates if the pin is used as source of external
+    interrupts.
+
+Example:
+     ucc_pin@01 {
+	linux,phandle = <140001>;
+	pio-map = <
+	/* port  pin  dir  open_drain  assignment  has_irq */
+		0  3  1  0  1  0 	/* TxD0 */
+		0  4  1  0  1  0 	/* TxD1 */
+		0  5  1  0  1  0 	/* TxD2 */
+		0  6  1  0  1  0 	/* TxD3 */
+		1  6  1  0  3  0 	/* TxD4 */
+		1  7  1  0  1  0 	/* TxD5 */
+		1  9  1  0  2  0 	/* TxD6 */
+		1  a  1  0  2  0 	/* TxD7 */
+		0  9  2  0  1  0 	/* RxD0 */
+		0  a  2  0  1  0 	/* RxD1 */
+		0  b  2  0  1  0 	/* RxD2 */
+		0  c  2  0  1  0 	/* RxD3 */
+		0  d  2  0  1  0 	/* RxD4 */
+		1  1  2  0  2  0 	/* RxD5 */
+		1  0  2  0  2  0 	/* RxD6 */
+		1  4  2  0  2  0 	/* RxD7 */
+		0  7  1  0  1  0 	/* TX_EN */
+		0  8  1  0  1  0 	/* TX_ER */
+		0  f  2  0  1  0 	/* RX_DV */
+		0  10 2  0  1  0 	/* RX_ER */
+		0  0  2  0  1  0 	/* RX_CLK */
+		2  9  1  0  3  0 	/* GTX_CLK - CLK10 */
+		2  8  2  0  1  0>;	/* GTX125 - CLK9 */
+     };
+
+

Documentation/powerpc/dts-bindings/fsl/cpm_qe/qe/ucc.txt

@@ -0,0 +1,70 @@
+* UCC (Unified Communications Controllers)
+
+Required properties:
+- device_type : should be "network", "hldc", "uart", "transparent"
+  "bisync", "atm", or "serial".
+- compatible : could be "ucc_geth" or "fsl_atm" and so on.
+- cell-index : the ucc number(1-8), corresponding to UCCx in UM.
+- reg : Offset and length of the register set for the device
+- interrupts : <a b> where a is the interrupt number and b is a
+  field that represents an encoding of the sense and level
+  information for the interrupt.  This should be encoded based on
+  the information in section 2) depending on the type of interrupt
+  controller you have.
+- interrupt-parent : the phandle for the interrupt controller that
+  services interrupts for this device.
+- pio-handle : The phandle for the Parallel I/O port configuration.
+- port-number : for UART drivers, the port number to use, between 0 and 3.
+  This usually corresponds to the /dev/ttyQE device, e.g. <0> = /dev/ttyQE0.
+  The port number is added to the minor number of the device.  Unlike the
+  CPM UART driver, the port-number is required for the QE UART driver.
+- soft-uart : for UART drivers, if specified this means the QE UART device
+  driver should use "Soft-UART" mode, which is needed on some SOCs that have
+  broken UART hardware.  Soft-UART is provided via a microcode upload.
+- rx-clock-name: the UCC receive clock source
+  "none": clock source is disabled
+  "brg1" through "brg16": clock source is BRG1-BRG16, respectively
+  "clk1" through "clk24": clock source is CLK1-CLK24, respectively
+- tx-clock-name: the UCC transmit clock source
+  "none": clock source is disabled
+  "brg1" through "brg16": clock source is BRG1-BRG16, respectively
+  "clk1" through "clk24": clock source is CLK1-CLK24, respectively
+The following two properties are deprecated.  rx-clock has been replaced
+with rx-clock-name, and tx-clock has been replaced with tx-clock-name.
+Drivers that currently use the deprecated properties should continue to
+do so, in order to support older device trees, but they should be updated
+to check for the new properties first.
+- rx-clock : represents the UCC receive clock source.
+  0x00 : clock source is disabled;
+  0x1~0x10 : clock source is BRG1~BRG16 respectively;
+  0x11~0x28: clock source is QE_CLK1~QE_CLK24 respectively.
+- tx-clock: represents the UCC transmit clock source;
+  0x00 : clock source is disabled;
+  0x1~0x10 : clock source is BRG1~BRG16 respectively;
+  0x11~0x28: clock source is QE_CLK1~QE_CLK24 respectively.
+
+Required properties for network device_type:
+- mac-address : list of bytes representing the ethernet address.
+- phy-handle : The phandle for the PHY connected to this controller.
+
+Recommended properties:
+- phy-connection-type : a string naming the controller/PHY interface type,
+  i.e., "mii" (default), "rmii", "gmii", "rgmii", "rgmii-id" (Internal
+  Delay), "rgmii-txid" (delay on TX only), "rgmii-rxid" (delay on RX only),
+  "tbi", or "rtbi".
+
+Example:
+	ucc@2000 {
+		device_type = "network";
+		compatible = "ucc_geth";
+		cell-index = <1>;
+		reg = <2000 200>;
+		interrupts = <a0 0>;
+		interrupt-parent = <700>;
+		mac-address = [ 00 04 9f 00 23 23 ];
+		rx-clock = "none";
+		tx-clock = "clk9";
+		phy-handle = <212000>;
+		phy-connection-type = "gmii";
+		pio-handle = <140001>;
+	};

Documentation/powerpc/dts-bindings/fsl/cpm_qe/qe/usb.txt

@@ -0,0 +1,22 @@
+* USB (Universal Serial Bus Controller)
+
+Required properties:
+- compatible : could be "qe_udc" or "fhci-hcd".
+- mode : the could be "host" or "slave".
+- reg : Offset and length of the register set for the device
+- interrupts : <a b> where a is the interrupt number and b is a
+  field that represents an encoding of the sense and level
+  information for the interrupt.  This should be encoded based on
+  the information in section 2) depending on the type of interrupt
+  controller you have.
+- interrupt-parent : the phandle for the interrupt controller that
+  services interrupts for this device.
+
+Example(slave):
+	usb@6c0 {
+		compatible = "qe_udc";
+		reg = <6c0 40>;
+		interrupts = <8b 0>;
+		interrupt-parent = <700>;
+		mode = "slave";
+	};

Documentation/powerpc/dts-bindings/fsl/cpm_qe/serial.txt

@@ -0,0 +1,21 @@
+* Serial
+
+Currently defined compatibles:
+- fsl,cpm1-smc-uart
+- fsl,cpm2-smc-uart
+- fsl,cpm1-scc-uart
+- fsl,cpm2-scc-uart
+- fsl,qe-uart
+
+Example:
+
+	serial@11a00 {
+		device_type = "serial";
+		compatible = "fsl,mpc8272-scc-uart",
+			     "fsl,cpm2-scc-uart";
+		reg = <11a00 20 8000 100>;
+		interrupts = <28 8>;
+		interrupt-parent = <&PIC>;
+		fsl,cpm-brg = <1>;
+		fsl,cpm-command = <00800000>;
+	};

Documentation/powerpc/dts-bindings/fsl/diu.txt

@@ -0,0 +1,18 @@
+* Freescale Display Interface Unit
+
+The Freescale DIU is a LCD controller, with proper hardware, it can also
+drive DVI monitors.
+
+Required properties:
+- compatible : should be "fsl-diu".
+- reg : should contain at least address and length of the DIU register
+  set.
+- Interrupts : one DIU interrupt should be describe here.
+
+Example (MPC8610HPCD):
+	display@2c000 {
+		compatible = "fsl,diu";
+		reg = <0x2c000 100>;
+		interrupts = <72 2>;
+		interrupt-parent = <&mpic>;
+	};

Documentation/powerpc/dts-bindings/fsl/dma.txt

@@ -0,0 +1,127 @@
+* Freescale 83xx DMA Controller
+
+Freescale PowerPC 83xx have on chip general purpose DMA controllers.
+
+Required properties:
+
+- compatible        : compatible list, contains 2 entries, first is
+		 "fsl,CHIP-dma", where CHIP is the processor
+		 (mpc8349, mpc8360, etc.) and the second is
+		 "fsl,elo-dma"
+- reg               : <registers mapping for DMA general status reg>
+- ranges		: Should be defined as specified in 1) to describe the
+		  DMA controller channels.
+- cell-index        : controller index.  0 for controller @ 0x8100
+- interrupts        : <interrupt mapping for DMA IRQ>
+- interrupt-parent  : optional, if needed for interrupt mapping
+
+
+- DMA channel nodes:
+        - compatible        : compatible list, contains 2 entries, first is
+			 "fsl,CHIP-dma-channel", where CHIP is the processor
+			 (mpc8349, mpc8350, etc.) and the second is
+			 "fsl,elo-dma-channel"
+        - reg               : <registers mapping for channel>
+        - cell-index        : dma channel index starts at 0.
+
+Optional properties:
+        - interrupts        : <interrupt mapping for DMA channel IRQ>
+			  (on 83xx this is expected to be identical to
+			   the interrupts property of the parent node)
+        - interrupt-parent  : optional, if needed for interrupt mapping
+
+Example:
+	dma@82a8 {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		compatible = "fsl,mpc8349-dma", "fsl,elo-dma";
+		reg = <82a8 4>;
+		ranges = <0 8100 1a4>;
+		interrupt-parent = <&ipic>;
+		interrupts = <47 8>;
+		cell-index = <0>;
+		dma-channel@0 {
+			compatible = "fsl,mpc8349-dma-channel", "fsl,elo-dma-channel";
+			cell-index = <0>;
+			reg = <0 80>;
+		};
+		dma-channel@80 {
+			compatible = "fsl,mpc8349-dma-channel", "fsl,elo-dma-channel";
+			cell-index = <1>;
+			reg = <80 80>;
+		};
+		dma-channel@100 {
+			compatible = "fsl,mpc8349-dma-channel", "fsl,elo-dma-channel";
+			cell-index = <2>;
+			reg = <100 80>;
+		};
+		dma-channel@180 {
+			compatible = "fsl,mpc8349-dma-channel", "fsl,elo-dma-channel";
+			cell-index = <3>;
+			reg = <180 80>;
+		};
+	};
+
+* Freescale 85xx/86xx DMA Controller
+
+Freescale PowerPC 85xx/86xx have on chip general purpose DMA controllers.
+
+Required properties:
+
+- compatible        : compatible list, contains 2 entries, first is
+		 "fsl,CHIP-dma", where CHIP is the processor
+		 (mpc8540, mpc8540, etc.) and the second is
+		 "fsl,eloplus-dma"
+- reg               : <registers mapping for DMA general status reg>
+- cell-index        : controller index.  0 for controller @ 0x21000,
+                                         1 for controller @ 0xc000
+- ranges		: Should be defined as specified in 1) to describe the
+		  DMA controller channels.
+
+- DMA channel nodes:
+        - compatible        : compatible list, contains 2 entries, first is
+			 "fsl,CHIP-dma-channel", where CHIP is the processor
+			 (mpc8540, mpc8560, etc.) and the second is
+			 "fsl,eloplus-dma-channel"
+        - cell-index        : dma channel index starts at 0.
+        - reg               : <registers mapping for channel>
+        - interrupts        : <interrupt mapping for DMA channel IRQ>
+        - interrupt-parent  : optional, if needed for interrupt mapping
+
+Example:
+	dma@21300 {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		compatible = "fsl,mpc8540-dma", "fsl,eloplus-dma";
+		reg = <21300 4>;
+		ranges = <0 21100 200>;
+		cell-index = <0>;
+		dma-channel@0 {
+			compatible = "fsl,mpc8540-dma-channel", "fsl,eloplus-dma-channel";
+			reg = <0 80>;
+			cell-index = <0>;
+			interrupt-parent = <&mpic>;
+			interrupts = <14 2>;
+		};
+		dma-channel@80 {
+			compatible = "fsl,mpc8540-dma-channel", "fsl,eloplus-dma-channel";
+			reg = <80 80>;
+			cell-index = <1>;
+			interrupt-parent = <&mpic>;
+			interrupts = <15 2>;
+		};
+		dma-channel@100 {
+			compatible = "fsl,mpc8540-dma-channel", "fsl,eloplus-dma-channel";
+			reg = <100 80>;
+			cell-index = <2>;
+			interrupt-parent = <&mpic>;
+			interrupts = <16 2>;
+		};
+		dma-channel@180 {
+			compatible = "fsl,mpc8540-dma-channel", "fsl,eloplus-dma-channel";
+			reg = <180 80>;
+			cell-index = <3>;
+			interrupt-parent = <&mpic>;
+			interrupts = <17 2>;
+		};
+	};

Documentation/powerpc/dts-bindings/fsl/gtm.txt

@@ -0,0 +1,31 @@
+* Freescale General-purpose Timers Module
+
+Required properties:
+  - compatible : should be
+    "fsl,<chip>-gtm", "fsl,gtm" for SOC GTMs
+    "fsl,<chip>-qe-gtm", "fsl,qe-gtm", "fsl,gtm" for QE GTMs
+    "fsl,<chip>-cpm2-gtm", "fsl,cpm2-gtm", "fsl,gtm" for CPM2 GTMs
+  - reg : should contain gtm registers location and length (0x40).
+  - interrupts : should contain four interrupts.
+  - interrupt-parent : interrupt source phandle.
+  - clock-frequency : specifies the frequency driving the timer.
+
+Example:
+
+timer@500 {
+	compatible = "fsl,mpc8360-gtm", "fsl,gtm";
+	reg = <0x500 0x40>;
+	interrupts = <90 8 78 8 84 8 72 8>;
+	interrupt-parent = <&ipic>;
+	/* filled by u-boot */
+	clock-frequency = <0>;
+};
+
+timer@440 {
+	compatible = "fsl,mpc8360-qe-gtm", "fsl,qe-gtm", "fsl,gtm";
+	reg = <0x440 0x40>;
+	interrupts = <12 13 14 15>;
+	interrupt-parent = <&qeic>;
+	/* filled by u-boot */
+	clock-frequency = <0>;
+};

Documentation/powerpc/dts-bindings/fsl/guts.txt

@@ -0,0 +1,25 @@
+* Global Utilities Block
+
+The global utilities block controls power management, I/O device
+enabling, power-on-reset configuration monitoring, general-purpose
+I/O signal configuration, alternate function selection for multiplexed
+signals, and clock control.
+
+Required properties:
+
+ - compatible : Should define the compatible device type for
+   global-utilities.
+ - reg : Offset and length of the register set for the device.
+
+Recommended properties:
+
+ - fsl,has-rstcr : Indicates that the global utilities register set
+   contains a functioning "reset control register" (i.e. the board
+   is wired to reset upon setting the HRESET_REQ bit in this register).
+
+Example:
+	global-utilities@e0000 {	/* global utilities block */
+		compatible = "fsl,mpc8548-guts";
+		reg = <e0000 1000>;
+		fsl,has-rstcr;
+	};

Documentation/powerpc/dts-bindings/fsl/i2c.txt

@@ -0,0 +1,32 @@
+* I2C
+
+Required properties :
+
+ - device_type : Should be "i2c"
+ - reg : Offset and length of the register set for the device
+
+Recommended properties :
+
+ - compatible : Should be "fsl-i2c" for parts compatible with
+   Freescale I2C specifications.
+ - interrupts : <a b> where a is the interrupt number and b is a
+   field that represents an encoding of the sense and level
+   information for the interrupt.  This should be encoded based on
+   the information in section 2) depending on the type of interrupt
+   controller you have.
+ - interrupt-parent : the phandle for the interrupt controller that
+   services interrupts for this device.
+ - dfsrr : boolean; if defined, indicates that this I2C device has
+   a digital filter sampling rate register
+ - fsl5200-clocking : boolean; if defined, indicated that this device
+   uses the FSL 5200 clocking mechanism.
+
+Example :
+	i2c@3000 {
+		interrupt-parent = <40000>;
+		interrupts = <1b 3>;
+		reg = <3000 18>;
+		device_type = "i2c";
+		compatible  = "fsl-i2c";
+		dfsrr;
+	};

Documentation/powerpc/dts-bindings/fsl/lbc.txt

@@ -0,0 +1,35 @@
+* Chipselect/Local Bus
+
+Properties:
+- name : Should be localbus
+- #address-cells : Should be either two or three.  The first cell is the
+                   chipselect number, and the remaining cells are the
+                   offset into the chipselect.
+- #size-cells : Either one or two, depending on how large each chipselect
+                can be.
+- ranges : Each range corresponds to a single chipselect, and cover
+           the entire access window as configured.
+
+Example:
+	localbus@f0010100 {
+		compatible = "fsl,mpc8272-localbus",
+			   "fsl,pq2-localbus";
+		#address-cells = <2>;
+		#size-cells = <1>;
+		reg = <f0010100 40>;
+
+		ranges = <0 0 fe000000 02000000
+			  1 0 f4500000 00008000>;
+
+		flash@0,0 {
+			compatible = "jedec-flash";
+			reg = <0 0 2000000>;
+			bank-width = <4>;
+			device-width = <1>;
+		};
+
+		board-control@1,0 {
+			reg = <1 0 20>;
+			compatible = "fsl,mpc8272ads-bcsr";
+		};
+	};

Documentation/powerpc/dts-bindings/fsl/msi-pic.txt

@@ -0,0 +1,36 @@
+* Freescale MSI interrupt controller
+
+Reguired properities:
+- compatible : compatible list, contains 2 entries,
+  first is "fsl,CHIP-msi", where CHIP is the processor(mpc8610, mpc8572,
+  etc.) and the second is "fsl,mpic-msi" or "fsl,ipic-msi" depending on
+  the parent type.
+- reg : should contain the address and the length of the shared message
+  interrupt register set.
+- msi-available-ranges: use <start count> style section to define which
+  msi interrupt can be used in the 256 msi interrupts. This property is
+  optional, without this, all the 256 MSI interrupts can be used.
+- interrupts : each one of the interrupts here is one entry per 32 MSIs,
+  and routed to the host interrupt controller. the interrupts should
+  be set as edge sensitive.
+- interrupt-parent: the phandle for the interrupt controller
+  that services interrupts for this device. for 83xx cpu, the interrupts
+  are routed to IPIC, and for 85xx/86xx cpu the interrupts are routed
+  to MPIC.
+
+Example:
+	msi@41600 {
+		compatible = "fsl,mpc8610-msi", "fsl,mpic-msi";
+		reg = <0x41600 0x80>;
+		msi-available-ranges = <0 0x100>;
+		interrupts = <
+			0xe0 0
+			0xe1 0
+			0xe2 0
+			0xe3 0
+			0xe4 0
+			0xe5 0
+			0xe6 0
+			0xe7 0>;
+		interrupt-parent = <&mpic>;
+	};

Documentation/powerpc/dts-bindings/fsl/sata.txt

@@ -0,0 +1,29 @@
+* Freescale 8xxx/3.0 Gb/s SATA nodes
+
+SATA nodes are defined to describe on-chip Serial ATA controllers.
+Each SATA port should have its own node.
+
+Required properties:
+- compatible        : compatible list, contains 2 entries, first is
+		 "fsl,CHIP-sata", where CHIP is the processor
+		 (mpc8315, mpc8379, etc.) and the second is
+		 "fsl,pq-sata"
+- interrupts        : <interrupt mapping for SATA IRQ>
+- cell-index        : controller index.
+                          1 for controller @ 0x18000
+                          2 for controller @ 0x19000
+                          3 for controller @ 0x1a000
+                          4 for controller @ 0x1b000
+
+Optional properties:
+- interrupt-parent  : optional, if needed for interrupt mapping
+- reg               : <registers mapping>
+
+Example:
+	sata@18000 {
+		compatible = "fsl,mpc8379-sata", "fsl,pq-sata";
+		reg = <0x18000 0x1000>;
+		cell-index = <1>;
+		interrupts = <2c 8>;
+		interrupt-parent = < &ipic >;
+	};

Documentation/powerpc/dts-bindings/fsl/sec.txt

@@ -0,0 +1,68 @@
+Freescale SoC SEC Security Engines
+
+Required properties:
+
+- compatible : Should contain entries for this and backward compatible
+  SEC versions, high to low, e.g., "fsl,sec2.1", "fsl,sec2.0"
+- reg : Offset and length of the register set for the device
+- interrupts : the SEC's interrupt number
+- fsl,num-channels : An integer representing the number of channels
+  available.
+- fsl,channel-fifo-len : An integer representing the number of
+  descriptor pointers each channel fetch fifo can hold.
+- fsl,exec-units-mask : The bitmask representing what execution units
+  (EUs) are available. It's a single 32-bit cell. EU information
+  should be encoded following the SEC's Descriptor Header Dword
+  EU_SEL0 field documentation, i.e. as follows:
+
+	bit 0  = reserved - should be 0
+	bit 1  = set if SEC has the ARC4 EU (AFEU)
+	bit 2  = set if SEC has the DES/3DES EU (DEU)
+	bit 3  = set if SEC has the message digest EU (MDEU/MDEU-A)
+	bit 4  = set if SEC has the random number generator EU (RNG)
+	bit 5  = set if SEC has the public key EU (PKEU)
+	bit 6  = set if SEC has the AES EU (AESU)
+	bit 7  = set if SEC has the Kasumi EU (KEU)
+	bit 8  = set if SEC has the CRC EU (CRCU)
+	bit 11 = set if SEC has the message digest EU extended alg set (MDEU-B)
+
+remaining bits are reserved for future SEC EUs.
+
+- fsl,descriptor-types-mask : The bitmask representing what descriptors
+  are available. It's a single 32-bit cell. Descriptor type information
+  should be encoded following the SEC's Descriptor Header Dword DESC_TYPE
+  field documentation, i.e. as follows:
+
+	bit 0  = set if SEC supports the aesu_ctr_nonsnoop desc. type
+	bit 1  = set if SEC supports the ipsec_esp descriptor type
+	bit 2  = set if SEC supports the common_nonsnoop desc. type
+	bit 3  = set if SEC supports the 802.11i AES ccmp desc. type
+	bit 4  = set if SEC supports the hmac_snoop_no_afeu desc. type
+	bit 5  = set if SEC supports the srtp descriptor type
+	bit 6  = set if SEC supports the non_hmac_snoop_no_afeu desc.type
+	bit 7  = set if SEC supports the pkeu_assemble descriptor type
+	bit 8  = set if SEC supports the aesu_key_expand_output desc.type
+	bit 9  = set if SEC supports the pkeu_ptmul descriptor type
+	bit 10 = set if SEC supports the common_nonsnoop_afeu desc. type
+	bit 11 = set if SEC supports the pkeu_ptadd_dbl descriptor type
+
+  ..and so on and so forth.
+
+Optional properties:
+
+- interrupt-parent : the phandle for the interrupt controller that
+  services interrupts for this device.
+
+Example:
+
+	/* MPC8548E */
+	crypto@30000 {
+		compatible = "fsl,sec2.1", "fsl,sec2.0";
+		reg = <0x30000 0x10000>;
+		interrupts = <29 2>;
+		interrupt-parent = <&mpic>;
+		fsl,num-channels = <4>;
+		fsl,channel-fifo-len = <24>;
+		fsl,exec-units-mask = <0xfe>;
+		fsl,descriptor-types-mask = <0x12b0ebf>;
+	};

Documentation/powerpc/dts-bindings/fsl/spi.txt

@@ -0,0 +1,24 @@
+* SPI (Serial Peripheral Interface)
+
+Required properties:
+- cell-index : SPI controller index.
+- compatible : should be "fsl,spi".
+- mode : the SPI operation mode, it can be "cpu" or "cpu-qe".
+- reg : Offset and length of the register set for the device
+- interrupts : <a b> where a is the interrupt number and b is a
+  field that represents an encoding of the sense and level
+  information for the interrupt.  This should be encoded based on
+  the information in section 2) depending on the type of interrupt
+  controller you have.
+- interrupt-parent : the phandle for the interrupt controller that
+  services interrupts for this device.
+
+Example:
+	spi@4c0 {
+		cell-index = <0>;
+		compatible = "fsl,spi";
+		reg = <4c0 40>;
+		interrupts = <82 0>;
+		interrupt-parent = <700>;
+		mode = "cpu";
+	};

Documentation/powerpc/dts-bindings/fsl/ssi.txt

@@ -0,0 +1,38 @@
+Freescale Synchronous Serial Interface
+
+The SSI is a serial device that communicates with audio codecs.  It can
+be programmed in AC97, I2S, left-justified, or right-justified modes.
+
+Required properties:
+- compatible	  : compatible list, containing "fsl,ssi"
+- cell-index	  : the SSI, <0> = SSI1, <1> = SSI2, and so on
+- reg		  : offset and length of the register set for the device
+- interrupts	  : <a b> where a is the interrupt number and b is a
+                     field that represents an encoding of the sense and
+		    level information for the interrupt.  This should be
+		    encoded based on the information in section 2)
+		    depending on the type of interrupt controller you
+		    have.
+- interrupt-parent : the phandle for the interrupt controller that
+                     services interrupts for this device.
+- fsl,mode	  : the operating mode for the SSI interface
+		    "i2s-slave" - I2S mode, SSI is clock slave
+		    "i2s-master" - I2S mode, SSI is clock master
+		    "lj-slave" - left-justified mode, SSI is clock slave
+		    "lj-master" - l.j. mode, SSI is clock master
+		    "rj-slave" - right-justified mode, SSI is clock slave
+		    "rj-master" - r.j., SSI is clock master
+		    "ac97-slave" - AC97 mode, SSI is clock slave
+		    "ac97-master" - AC97 mode, SSI is clock master
+
+Optional properties:
+- codec-handle	  : phandle to a 'codec' node that defines an audio
+		    codec connected to this SSI.  This node is typically
+		    a child of an I2C or other control node.
+
+Child 'codec' node required properties:
+- compatible	  : compatible list, contains the name of the codec
+
+Child 'codec' node optional properties:
+- clock-frequency  : The frequency of the input clock, which typically
+                     comes from an on-board dedicated oscillator.