Merge commit 'v2.6.35-rc1' into for-2.6.36

Documentation/00-INDEX

@@ -250,6 +250,8 @@ numastat.txt
 	- info on how to read Numa policy hit/miss statistics in sysfs.
 oops-tracing.txt
 	- how to decode those nasty internal kernel error dump messages.
+padata.txt
+	- An introduction to the "padata" parallel execution API
 parisc/
 	- directory with info on using Linux on PA-RISC architecture.
 parport.txt

Documentation/ABI/obsolete/sysfs-bus-usb

@@ -0,0 +1,31 @@
+What:		/sys/bus/usb/devices/.../power/level
+Date:		March 2007
+KernelVersion:	2.6.21
+Contact:	Alan Stern <stern@rowland.harvard.edu>
+Description:
+		Each USB device directory will contain a file named
+		power/level.  This file holds a power-level setting for
+		the device, either "on" or "auto".
+
+		"on" means that the device is not allowed to autosuspend,
+		although normal suspends for system sleep will still
+		be honored.  "auto" means the device will autosuspend
+		and autoresume in the usual manner, according to the
+		capabilities of its driver.
+
+		During normal use, devices should be left in the "auto"
+		level.  The "on" level is meant for administrative uses.
+		If you want to suspend a device immediately but leave it
+		free to wake up in response to I/O requests, you should
+		write "0" to power/autosuspend.
+
+		Device not capable of proper suspend and resume should be
+		left in the "on" level.  Although the USB spec requires
+		devices to support suspend/resume, many of them do not.
+		In fact so many don't that by default, the USB core
+		initializes all non-hub devices in the "on" level.  Some
+		drivers may change this setting when they are bound.
+
+		This file is deprecated and will be removed after 2010.
+		Use the power/control file instead; it does exactly the
+		same thing.

Documentation/ABI/obsolete/sysfs-class-rfkill

@@ -0,0 +1,29 @@
+rfkill - radio frequency (RF) connector kill switch support
+
+For details to this subsystem look at Documentation/rfkill.txt.
+
+What:		/sys/class/rfkill/rfkill[0-9]+/state
+Date:		09-Jul-2007
+KernelVersion	v2.6.22
+Contact:	linux-wireless@vger.kernel.org
+Description: 	Current state of the transmitter.
+		This file is deprecated and sheduled to be removed in 2014,
+		because its not possible to express the 'soft and hard block'
+		state of the rfkill driver.
+Values: 	A numeric value.
+		0: RFKILL_STATE_SOFT_BLOCKED
+			transmitter is turned off by software
+		1: RFKILL_STATE_UNBLOCKED
+			transmitter is (potentially) active
+		2: RFKILL_STATE_HARD_BLOCKED
+			transmitter is forced off by something outside of
+			the driver's control.
+
+What:		/sys/class/rfkill/rfkill[0-9]+/claim
+Date:		09-Jul-2007
+KernelVersion	v2.6.22
+Contact:	linux-wireless@vger.kernel.org
+Description:	This file is deprecated because there no longer is a way to
+		claim just control over a single rfkill instance.
+		This file is scheduled to be removed in 2012.
+Values: 	0: Kernel handles events

Documentation/ABI/stable/sysfs-class-rfkill

@@ -0,0 +1,67 @@
+rfkill - radio frequency (RF) connector kill switch support
+
+For details to this subsystem look at Documentation/rfkill.txt.
+
+For the deprecated /sys/class/rfkill/*/state and
+/sys/class/rfkill/*/claim knobs of this interface look in
+Documentation/ABI/obsolete/sysfs-class-rfkill.
+
+What: 		/sys/class/rfkill
+Date:		09-Jul-2007
+KernelVersion:	v2.6.22
+Contact:	linux-wireless@vger.kernel.org,
+Description: 	The rfkill class subsystem folder.
+		Each registered rfkill driver is represented by an rfkillX
+		subfolder (X being an integer > 0).
+
+
+What:		/sys/class/rfkill/rfkill[0-9]+/name
+Date:		09-Jul-2007
+KernelVersion	v2.6.22
+Contact:	linux-wireless@vger.kernel.org
+Description: 	Name assigned by driver to this key (interface or driver name).
+Values: 	arbitrary string.
+
+
+What: 		/sys/class/rfkill/rfkill[0-9]+/type
+Date:		09-Jul-2007
+KernelVersion	v2.6.22
+Contact:	linux-wireless@vger.kernel.org
+Description: 	Driver type string ("wlan", "bluetooth", etc).
+Values: 	See include/linux/rfkill.h.
+
+
+What:		/sys/class/rfkill/rfkill[0-9]+/persistent
+Date:		09-Jul-2007
+KernelVersion	v2.6.22
+Contact:	linux-wireless@vger.kernel.org
+Description: 	Whether the soft blocked state is initialised from non-volatile
+		storage at startup.
+Values: 	A numeric value.
+		0: false
+		1: true
+
+
+What:		/sys/class/rfkill/rfkill[0-9]+/hard
+Date:		12-March-2010
+KernelVersion	v2.6.34
+Contact:	linux-wireless@vger.kernel.org
+Description: 	Current hardblock state. This file is read only.
+Values: 	A numeric value.
+		0: inactive
+			The transmitter is (potentially) active.
+		1: active
+			The transmitter is forced off by something outside of
+			the driver's control.
+
+
+What:		/sys/class/rfkill/rfkill[0-9]+/soft
+Date:		12-March-2010
+KernelVersion	v2.6.34
+Contact:	linux-wireless@vger.kernel.org
+Description:	Current softblock state. This file is read and write.
+Values: 	A numeric value.
+		0: inactive
+			The transmitter is (potentially) active.
+		1: active
+			The transmitter is turned off by software.

Documentation/ABI/testing/sysfs-bus-pci

@@ -133,6 +133,46 @@ Description:
 		The symbolic link points to the PCI device sysfs entry of the
 		Physical Function this device associates with.
 
+
+What:		/sys/bus/pci/slots/...
+Date:		April 2005 (possibly older)
+KernelVersion:	2.6.12 (possibly older)
+Contact:	linux-pci@vger.kernel.org
+Description:
+		When the appropriate driver is loaded, it will create a
+		directory per claimed physical PCI slot in
+		/sys/bus/pci/slots/.  The names of these directories are
+		specific to the driver, which in turn, are specific to the
+		platform, but in general, should match the label on the
+		machine's physical chassis.
+
+		The drivers that can create slot directories include the
+		PCI hotplug drivers, and as of 2.6.27, the pci_slot driver.
+
+		The slot directories contain, at a minimum, a file named
+		'address' which contains the PCI bus:device:function tuple.
+		Other files may appear as well, but are specific to the
+		driver.
+
+What:		/sys/bus/pci/slots/.../function[0-7]
+Date:		March 2010
+KernelVersion:	2.6.35
+Contact:	linux-pci@vger.kernel.org
+Description:
+		If PCI slot directories (as described above) are created,
+		and the physical slot is actually populated with a device,
+		symbolic links in the slot directory pointing to the
+		device's PCI functions are created as well.
+
+What:		/sys/bus/pci/devices/.../slot
+Date:		March 2010
+KernelVersion:	2.6.35
+Contact:	linux-pci@vger.kernel.org
+Description:
+		If PCI slot directories (as described above) are created,
+		a symbolic link pointing to the slot directory will be
+		created as well.
+
 What:		/sys/bus/pci/slots/.../module
 Date:		June 2009
 Contact:	linux-pci@vger.kernel.org

Documentation/ABI/testing/sysfs-bus-usb

@@ -14,34 +14,6 @@ Description:
 		The autosuspend delay for newly-created devices is set to
 		the value of the usbcore.autosuspend module parameter.
 
-What:		/sys/bus/usb/devices/.../power/level
-Date:		March 2007
-KernelVersion:	2.6.21
-Contact:	Alan Stern <stern@rowland.harvard.edu>
-Description:
-		Each USB device directory will contain a file named
-		power/level.  This file holds a power-level setting for
-		the device, either "on" or "auto".
-
-		"on" means that the device is not allowed to autosuspend,
-		although normal suspends for system sleep will still
-		be honored.  "auto" means the device will autosuspend
-		and autoresume in the usual manner, according to the
-		capabilities of its driver.
-
-		During normal use, devices should be left in the "auto"
-		level.  The "on" level is meant for administrative uses.
-		If you want to suspend a device immediately but leave it
-		free to wake up in response to I/O requests, you should
-		write "0" to power/autosuspend.
-
-		Device not capable of proper suspend and resume should be
-		left in the "on" level.  Although the USB spec requires
-		devices to support suspend/resume, many of them do not.
-		In fact so many don't that by default, the USB core
-		initializes all non-hub devices in the "on" level.  Some
-		drivers may change this setting when they are bound.
-
 What:		/sys/bus/usb/devices/.../power/persist
 Date:		May 2007
 KernelVersion:	2.6.23

Documentation/ABI/testing/sysfs-class-power

@@ -0,0 +1,20 @@
+What:		/sys/class/power/ds2760-battery.*/charge_now
+Date:		May 2010
+KernelVersion:	2.6.35
+Contact:	Daniel Mack <daniel@caiaq.de>
+Description:
+		This file is writeable and can be used to set the current
+		coloumb counter value inside the battery monitor chip. This
+		is needed for unavoidable corrections of aging batteries.
+		A userspace daemon can monitor the battery charging logic
+		and once the counter drops out of considerable bounds, take
+		appropriate action.
+
+What:		/sys/class/power/ds2760-battery.*/charge_full
+Date:		May 2010
+KernelVersion:	2.6.35
+Contact:	Daniel Mack <daniel@caiaq.de>
+Description:
+		This file is writeable and can be used to set the assumed
+		battery 'full level'. As batteries age, this value has to be
+		amended over time.

Documentation/ABI/testing/sysfs-devices-memory

@@ -43,7 +43,7 @@ Date:		September 2008
 Contact:	Badari Pulavarty <pbadari@us.ibm.com>
 Description:
 		The file /sys/devices/system/memory/memoryX/state
-		is read-write.  When read, it's contents show the
+		is read-write.  When read, its contents show the
 		online/offline state of the memory section.  When written,
 		root can toggle the the online/offline state of a removable
 		memory section (see removable file description above)

Documentation/ABI/testing/sysfs-devices-node

@@ -0,0 +1,7 @@
+What:		/sys/devices/system/node/nodeX/compact
+Date:		February 2010
+Contact:	Mel Gorman <mel@csn.ul.ie>
+Description:
+		When this file is written to, all memory within that node
+		will be compacted. When it completes, memory will be freed
+		into blocks which have as many contiguous pages as possible

Documentation/ABI/testing/sysfs-devices-platform-_UDC_-gadget

@@ -0,0 +1,9 @@
+What:		/sys/devices/platform/_UDC_/gadget/suspended
+Date:		April 2010
+Contact:	Fabien Chouteau <fabien.chouteau@barco.com>
+Description:
+		Show the suspend state of an USB composite gadget.
+		1 -> suspended
+		0 -> resumed
+
+		(_UDC_ is the name of the USB Device Controller driver)

Documentation/ABI/testing/sysfs-driver-hid-picolcd

@@ -0,0 +1,43 @@
+What:		/sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/operation_mode
+Date:		March 2010
+Contact:	Bruno Prémont <bonbons@linux-vserver.org>
+Description:	Make it possible to switch the PicoLCD device between LCD
+		(firmware) and bootloader (flasher) operation modes.
+
+		Reading: returns list of available modes, the active mode being
+		enclosed in brackets ('[' and ']')
+
+		Writing: causes operation mode switch. Permitted values are
+		the non-active mode names listed when read.
+
+		Note: when switching mode the current PicoLCD HID device gets
+		disconnected and reconnects after above delay (see attribute
+		operation_mode_delay for its value).
+
+
+What:		/sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/operation_mode_delay
+Date:		April 2010
+Contact:	Bruno Prémont <bonbons@linux-vserver.org>
+Description:	Delay PicoLCD waits before restarting in new mode when
+		operation_mode has changed.
+
+		Reading/Writing: It is expressed in ms and permitted range is
+		0..30000ms.
+
+
+What:		/sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/fb_update_rate
+Date:		March 2010
+Contact:	Bruno Prémont <bonbons@linux-vserver.org>
+Description:	Make it possible to adjust defio refresh rate.
+
+		Reading: returns list of available refresh rates (expressed in Hz),
+		the active refresh rate being enclosed in brackets ('[' and ']')
+
+		Writing: accepts new refresh rate expressed in integer Hz
+		within permitted rates.
+
+		Note: As device can barely do 2 complete refreshes a second
+		it only makes sense to adjust this value if only one or two
+		tiles get changed and it's not appropriate to expect the application
+		to flush it's tiny changes explicitely at higher than default rate.
+

Documentation/ABI/testing/sysfs-driver-hid-prodikeys

@@ -0,0 +1,29 @@
+What:		/sys/bus/hid/drivers/prodikeys/.../channel
+Date:		April 2010
+KernelVersion:	2.6.34
+Contact:	Don Prince <dhprince.devel@yahoo.co.uk>
+Description:
+		Allows control (via software) the midi channel to which
+		that the pc-midi keyboard will output.midi data.
+		Range: 0..15
+		Type:  Read/write
+What:		/sys/bus/hid/drivers/prodikeys/.../sustain
+Date:		April 2010
+KernelVersion:	2.6.34
+Contact:	Don Prince <dhprince.devel@yahoo.co.uk>
+Description:
+		Allows control (via software) the sustain duration of a
+		note held by the pc-midi driver.
+		0 means sustain mode is disabled.
+		Range: 0..5000 (milliseconds)
+		Type:  Read/write
+What:		/sys/bus/hid/drivers/prodikeys/.../octave
+Date:		April 2010
+KernelVersion:	2.6.34
+Contact:	Don Prince <dhprince.devel@yahoo.co.uk>
+Description:
+		Controls the octave shift modifier in the pc-midi driver.
+		The octave can be shifted via software up/down 2 octaves.
+		0 means the no ocatve shift.
+		Range: -2..2 (minus 2 to plus 2)
+		Type: Read/Write

Documentation/ABI/testing/sysfs-driver-hid-roccat-kone

@@ -0,0 +1,111 @@
+What:		/sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/actual_dpi
+Date:		March 2010
+Contact:	Stefan Achatz <erazor_de@users.sourceforge.net>
+Description:	It is possible to switch the dpi setting of the mouse with the
+		press of a button.
+		When read, this file returns the raw number of the actual dpi
+		setting reported by the mouse. This number has to be further
+		processed to receive the real dpi value.
+
+		VALUE DPI
+		1     800
+		2     1200
+		3     1600
+		4     2000
+		5     2400
+		6     3200
+
+		This file is readonly.
+
+What:		/sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/actual_profile
+Date:		March 2010
+Contact:	Stefan Achatz <erazor_de@users.sourceforge.net>
+Description:	When read, this file returns the number of the actual profile.
+		This file is readonly.
+
+What:		/sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/firmware_version
+Date:		March 2010
+Contact:	Stefan Achatz <erazor_de@users.sourceforge.net>
+Description:	When read, this file returns the raw integer version number of the
+		firmware reported by the mouse. Using the integer value eases
+		further usage in other programs. To receive the real version
+		number the decimal point has to be shifted 2 positions to the
+		left. E.g. a returned value of 138 means 1.38
+		This file is readonly.
+
+What:		/sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/kone_driver_version
+Date:		March 2010
+Contact:	Stefan Achatz <erazor_de@users.sourceforge.net>
+Description:	When read, this file returns the driver version.
+		The format of the string is "v<major>.<minor>.<patchlevel>".
+		This attribute is used by the userland tools to find the sysfs-
+		paths of installed kone-mice and determine the capabilites of
+		the driver. Versions of this driver for old kernels replace
+		usbhid instead of generic-usb. The way to scan for this file
+		has been chosen to provide a consistent way for all supported
+		kernel versions.
+		This file is readonly.
+
+What:		/sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/profile[1-5]
+Date:		March 2010
+Contact:	Stefan Achatz <erazor_de@users.sourceforge.net>
+Description:	The mouse can store 5 profiles which can be switched by the
+                press of a button. A profile holds informations like button
+                mappings, sensitivity, the colors of the 5 leds and light
+                effects.
+                When read, these files return the respective profile. The
+                returned data is 975 bytes in size.
+		When written, this file lets one write the respective profile
+		data back to the mouse. The data has to be 975 bytes long.
+		The mouse will reject invalid data, whereas the profile number
+		stored in the profile doesn't need to fit the number of the
+		store.
+
+What:		/sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/settings
+Date:		March 2010
+Contact:	Stefan Achatz <erazor_de@users.sourceforge.net>
+Description:	When read, this file returns the settings stored in the mouse.
+		The size of the data is 36 bytes and holds information like the
+		startup_profile, tcu state and calibration_data.
+		When written, this file lets write settings back to the mouse.
+		The data has to be 36 bytes long. The mouse will reject invalid
+		data.
+
+What:		/sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/startup_profile
+Date:		March 2010
+Contact:	Stefan Achatz <erazor_de@users.sourceforge.net>
+Description:	The integer value of this attribute ranges from 1 to 5.
+                When read, this attribute returns the number of the profile
+                that's active when the mouse is powered on.
+		When written, this file sets the number of the startup profile
+		and the mouse activates this profile immediately.
+
+What:		/sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/tcu
+Date:		March 2010
+Contact:	Stefan Achatz <erazor_de@users.sourceforge.net>
+Description:	The mouse has a "Tracking Control Unit" which lets the user
+		calibrate the laser power to fit the mousepad surface.
+		When read, this file returns the current state of the TCU,
+		where 0 means off and 1 means on.
+		Writing 0 in this file will switch the TCU off.
+		Writing 1 in this file will start the calibration which takes
+		around 6 seconds to complete and activates the TCU.
+
+What:		/sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/weight
+Date:		March 2010
+Contact:	Stefan Achatz <erazor_de@users.sourceforge.net>
+Description:	The mouse can be equipped with one of four supplied weights
+		ranging from 5 to 20 grams which are recognized by the mouse
+		and its value can be read out. When read, this file returns the
+		raw value returned by the mouse which eases further processing
+		in other software.
+		The values map to the weights as follows:
+
+		VALUE WEIGHT
+		0     none
+		1     5g
+		2     10g
+		3     15g
+		4     20g
+
+		This file is readonly.

Documentation/ABI/testing/sysfs-firmware-sfi

@@ -0,0 +1,15 @@
+What:		/sys/firmware/sfi/tables/
+Date:		May 2010
+Contact:	Len Brown <lenb@kernel.org>
+Description:
+		SFI defines a number of small static memory tables
+		so the kernel can get platform information from firmware.
+
+		The tables are defined in the latest SFI specification:
+		http://simplefirmware.org/documentation
+
+		While the tables are used by the kernel, user-space
+		can observe them this way:
+
+		# cd /sys/firmware/sfi/tables
+		# cat $TABLENAME > $TABLENAME.bin

Documentation/ABI/testing/sysfs-wacom

@@ -0,0 +1,10 @@
+What:		/sys/class/hidraw/hidraw*/device/speed
+Date:		April 2010
+Kernel Version:	2.6.35
+Contact:	linux-bluetooth@vger.kernel.org
+Description:
+		The /sys/class/hidraw/hidraw*/device/speed file controls
+		reporting speed of wacom bluetooth tablet. Reading from
+		this file returns 1 if tablet reports in high speed mode
+		or 0 otherwise. Writing to this file one of these values
+		switches reporting speed.

Documentation/Changes

@@ -49,7 +49,7 @@ o  oprofile               0.9                     # oprofiled --version
 o  udev                   081                     # udevinfo -V
 o  grub                   0.93                    # grub --version
 o  mcelog		  0.6
-o  iptables               1.4.1                   # iptables -V
+o  iptables               1.4.2                   # iptables -V
 
 
 Kernel compilation

Documentation/DMA-API-HOWTO.txt

@@ -0,0 +1,771 @@
+		     Dynamic DMA mapping Guide
+		     =========================
+
+		 David S. Miller <davem@redhat.com>
+		 Richard Henderson <rth@cygnus.com>
+		  Jakub Jelinek <jakub@redhat.com>
+
+This is a guide to device driver writers on how to use the DMA API
+with example pseudo-code.  For a concise description of the API, see
+DMA-API.txt.
+
+Most of the 64bit platforms have special hardware that translates bus
+addresses (DMA addresses) into physical addresses.  This is similar to
+how page tables and/or a TLB translates virtual addresses to physical
+addresses on a CPU.  This is needed so that e.g. PCI devices can
+access with a Single Address Cycle (32bit DMA address) any page in the
+64bit physical address space.  Previously in Linux those 64bit
+platforms had to set artificial limits on the maximum RAM size in the
+system, so that the virt_to_bus() static scheme works (the DMA address
+translation tables were simply filled on bootup to map each bus
+address to the physical page __pa(bus_to_virt())).
+
+So that Linux can use the dynamic DMA mapping, it needs some help from the
+drivers, namely it has to take into account that DMA addresses should be
+mapped only for the time they are actually used and unmapped after the DMA
+transfer.
+
+The following API will work of course even on platforms where no such
+hardware exists.
+
+Note that the DMA API works with any bus independent of the underlying
+microprocessor architecture. You should use the DMA API rather than
+the bus specific DMA API (e.g. pci_dma_*).
+
+First of all, you should make sure
+
+#include <linux/dma-mapping.h>
+
+is in your driver. This file will obtain for you the definition of the
+dma_addr_t (which can hold any valid DMA address for the platform)
+type which should be used everywhere you hold a DMA (bus) address
+returned from the DMA mapping functions.
+
+			 What memory is DMA'able?
+
+The first piece of information you must know is what kernel memory can
+be used with the DMA mapping facilities.  There has been an unwritten
+set of rules regarding this, and this text is an attempt to finally
+write them down.
+
+If you acquired your memory via the page allocator
+(i.e. __get_free_page*()) or the generic memory allocators
+(i.e. kmalloc() or kmem_cache_alloc()) then you may DMA to/from
+that memory using the addresses returned from those routines.
+
+This means specifically that you may _not_ use the memory/addresses
+returned from vmalloc() for DMA.  It is possible to DMA to the
+_underlying_ memory mapped into a vmalloc() area, but this requires
+walking page tables to get the physical addresses, and then
+translating each of those pages back to a kernel address using
+something like __va().  [ EDIT: Update this when we integrate
+Gerd Knorr's generic code which does this. ]
+
+This rule also means that you may use neither kernel image addresses
+(items in data/text/bss segments), nor module image addresses, nor
+stack addresses for DMA.  These could all be mapped somewhere entirely
+different than the rest of physical memory.  Even if those classes of
+memory could physically work with DMA, you'd need to ensure the I/O
+buffers were cacheline-aligned.  Without that, you'd see cacheline
+sharing problems (data corruption) on CPUs with DMA-incoherent caches.
+(The CPU could write to one word, DMA would write to a different one
+in the same cache line, and one of them could be overwritten.)
+
+Also, this means that you cannot take the return of a kmap()
+call and DMA to/from that.  This is similar to vmalloc().
+
+What about block I/O and networking buffers?  The block I/O and
+networking subsystems make sure that the buffers they use are valid
+for you to DMA from/to.
+
+			DMA addressing limitations
+
+Does your device have any DMA addressing limitations?  For example, is
+your device only capable of driving the low order 24-bits of address?
+If so, you need to inform the kernel of this fact.
+
+By default, the kernel assumes that your device can address the full
+32-bits.  For a 64-bit capable device, this needs to be increased.
+And for a device with limitations, as discussed in the previous
+paragraph, it needs to be decreased.
+
+Special note about PCI: PCI-X specification requires PCI-X devices to
+support 64-bit addressing (DAC) for all transactions.  And at least
+one platform (SGI SN2) requires 64-bit consistent allocations to
+operate correctly when the IO bus is in PCI-X mode.
+
+For correct operation, you must interrogate the kernel in your device
+probe routine to see if the DMA controller on the machine can properly
+support the DMA addressing limitation your device has.  It is good
+style to do this even if your device holds the default setting,
+because this shows that you did think about these issues wrt. your
+device.
+
+The query is performed via a call to dma_set_mask():
+
+	int dma_set_mask(struct device *dev, u64 mask);
+
+The query for consistent allocations is performed via a call to
+dma_set_coherent_mask():
+
+	int dma_set_coherent_mask(struct device *dev, u64 mask);
+
+Here, dev is a pointer to the device struct of your device, and mask
+is a bit mask describing which bits of an address your device
+supports.  It returns zero if your card can perform DMA properly on
+the machine given the address mask you provided.  In general, the
+device struct of your device is embedded in the bus specific device
+struct of your device.  For example, a pointer to the device struct of
+your PCI device is pdev->dev (pdev is a pointer to the PCI device
+struct of your device).
+
+If it returns non-zero, your device cannot perform DMA properly on
+this platform, and attempting to do so will result in undefined
+behavior.  You must either use a different mask, or not use DMA.
+
+This means that in the failure case, you have three options:
+
+1) Use another DMA mask, if possible (see below).
+2) Use some non-DMA mode for data transfer, if possible.
+3) Ignore this device and do not initialize it.
+
+It is recommended that your driver print a kernel KERN_WARNING message
+when you end up performing either #2 or #3.  In this manner, if a user
+of your driver reports that performance is bad or that the device is not
+even detected, you can ask them for the kernel messages to find out
+exactly why.
+
+The standard 32-bit addressing device would do something like this:
+
+	if (dma_set_mask(dev, DMA_BIT_MASK(32))) {
+		printk(KERN_WARNING
+		       "mydev: No suitable DMA available.\n");
+		goto ignore_this_device;
+	}
+
+Another common scenario is a 64-bit capable device.  The approach here
+is to try for 64-bit addressing, but back down to a 32-bit mask that
+should not fail.  The kernel may fail the 64-bit mask not because the
+platform is not capable of 64-bit addressing.  Rather, it may fail in
+this case simply because 32-bit addressing is done more efficiently
+than 64-bit addressing.  For example, Sparc64 PCI SAC addressing is
+more efficient than DAC addressing.
+
+Here is how you would handle a 64-bit capable device which can drive
+all 64-bits when accessing streaming DMA:
+
+	int using_dac;
+
+	if (!dma_set_mask(dev, DMA_BIT_MASK(64))) {
+		using_dac = 1;
+	} else if (!dma_set_mask(dev, DMA_BIT_MASK(32))) {
+		using_dac = 0;
+	} else {
+		printk(KERN_WARNING
+		       "mydev: No suitable DMA available.\n");
+		goto ignore_this_device;
+	}
+
+If a card is capable of using 64-bit consistent allocations as well,
+the case would look like this:
+
+	int using_dac, consistent_using_dac;
+
+	if (!dma_set_mask(dev, DMA_BIT_MASK(64))) {
+		using_dac = 1;
+	   	consistent_using_dac = 1;
+		dma_set_coherent_mask(dev, DMA_BIT_MASK(64));
+	} else if (!dma_set_mask(dev, DMA_BIT_MASK(32))) {
+		using_dac = 0;
+		consistent_using_dac = 0;
+		dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
+	} else {
+		printk(KERN_WARNING
+		       "mydev: No suitable DMA available.\n");
+		goto ignore_this_device;
+	}
+
+dma_set_coherent_mask() will always be able to set the same or a
+smaller mask as dma_set_mask(). However for the rare case that a
+device driver only uses consistent allocations, one would have to
+check the return value from dma_set_coherent_mask().
+
+Finally, if your device can only drive the low 24-bits of
+address you might do something like:
+
+	if (dma_set_mask(dev, DMA_BIT_MASK(24))) {
+		printk(KERN_WARNING
+		       "mydev: 24-bit DMA addressing not available.\n");
+		goto ignore_this_device;
+	}
+
+When dma_set_mask() is successful, and returns zero, the kernel saves
+away this mask you have provided.  The kernel will use this
+information later when you make DMA mappings.
+
+There is a case which we are aware of at this time, which is worth
+mentioning in this documentation.  If your device supports multiple
+functions (for example a sound card provides playback and record
+functions) and the various different functions have _different_
+DMA addressing limitations, you may wish to probe each mask and
+only provide the functionality which the machine can handle.  It
+is important that the last call to dma_set_mask() be for the
+most specific mask.
+
+Here is pseudo-code showing how this might be done:
+
+	#define PLAYBACK_ADDRESS_BITS	DMA_BIT_MASK(32)
+	#define RECORD_ADDRESS_BITS	DMA_BIT_MASK(24)
+
+	struct my_sound_card *card;
+	struct device *dev;
+
+	...
+	if (!dma_set_mask(dev, PLAYBACK_ADDRESS_BITS)) {
+		card->playback_enabled = 1;
+	} else {
+		card->playback_enabled = 0;
+		printk(KERN_WARNING "%s: Playback disabled due to DMA limitations.\n",
+		       card->name);
+	}
+	if (!dma_set_mask(dev, RECORD_ADDRESS_BITS)) {
+		card->record_enabled = 1;
+	} else {
+		card->record_enabled = 0;
+		printk(KERN_WARNING "%s: Record disabled due to DMA limitations.\n",
+		       card->name);
+	}
+
+A sound card was used as an example here because this genre of PCI
+devices seems to be littered with ISA chips given a PCI front end,
+and thus retaining the 16MB DMA addressing limitations of ISA.
+
+			Types of DMA mappings
+
+There are two types of DMA mappings:
+
+- Consistent DMA mappings which are usually mapped at driver
+  initialization, unmapped at the end and for which the hardware should
+  guarantee that the device and the CPU can access the data
+  in parallel and will see updates made by each other without any
+  explicit software flushing.
+
+  Think of "consistent" as "synchronous" or "coherent".
+
+  The current default is to return consistent memory in the low 32
+  bits of the bus space.  However, for future compatibility you should
+  set the consistent mask even if this default is fine for your
+  driver.
+
+  Good examples of what to use consistent mappings for are:
+
+	- Network card DMA ring descriptors.
+	- SCSI adapter mailbox command data structures.
+	- Device firmware microcode executed out of
+	  main memory.
+
+  The invariant these examples all require is that any CPU store
+  to memory is immediately visible to the device, and vice
+  versa.  Consistent mappings guarantee this.
+
+  IMPORTANT: Consistent DMA memory does not preclude the usage of
+             proper memory barriers.  The CPU may reorder stores to
+	     consistent memory just as it may normal memory.  Example:
+	     if it is important for the device to see the first word
+	     of a descriptor updated before the second, you must do
+	     something like:
+
+		desc->word0 = address;
+		wmb();
+		desc->word1 = DESC_VALID;
+
+             in order to get correct behavior on all platforms.
+
+	     Also, on some platforms your driver may need to flush CPU write
+	     buffers in much the same way as it needs to flush write buffers
+	     found in PCI bridges (such as by reading a register's value
+	     after writing it).
+
+- Streaming DMA mappings which are usually mapped for one DMA
+  transfer, unmapped right after it (unless you use dma_sync_* below)
+  and for which hardware can optimize for sequential accesses.
+
+  This of "streaming" as "asynchronous" or "outside the coherency
+  domain".
+
+  Good examples of what to use streaming mappings for are:
+
+	- Networking buffers transmitted/received by a device.
+	- Filesystem buffers written/read by a SCSI device.
+
+  The interfaces for using this type of mapping were designed in
+  such a way that an implementation can make whatever performance
+  optimizations the hardware allows.  To this end, when using
+  such mappings you must be explicit about what you want to happen.
+
+Neither type of DMA mapping has alignment restrictions that come from
+the underlying bus, although some devices may have such restrictions.
+Also, systems with caches that aren't DMA-coherent will work better
+when the underlying buffers don't share cache lines with other data.
+
+
+		 Using Consistent DMA mappings.
+
+To allocate and map large (PAGE_SIZE or so) consistent DMA regions,
+you should do:
+
+	dma_addr_t dma_handle;
+
+	cpu_addr = dma_alloc_coherent(dev, size, &dma_handle, gfp);
+
+where device is a struct device *. This may be called in interrupt
+context with the GFP_ATOMIC flag.
+
+Size is the length of the region you want to allocate, in bytes.
+
+This routine will allocate RAM for that region, so it acts similarly to
+__get_free_pages (but takes size instead of a page order).  If your
+driver needs regions sized smaller than a page, you may prefer using
+the dma_pool interface, described below.
+
+The consistent DMA mapping interfaces, for non-NULL dev, will by
+default return a DMA address which is 32-bit addressable.  Even if the
+device indicates (via DMA mask) that it may address the upper 32-bits,
+consistent allocation will only return > 32-bit addresses for DMA if
+the consistent DMA mask has been explicitly changed via
+dma_set_coherent_mask().  This is true of the dma_pool interface as
+well.
+
+dma_alloc_coherent returns two values: the virtual address which you
+can use to access it from the CPU and dma_handle which you pass to the
+card.
+
+The cpu return address and the DMA bus master address are both
+guaranteed to be aligned to the smallest PAGE_SIZE order which
+is greater than or equal to the requested size.  This invariant
+exists (for example) to guarantee that if you allocate a chunk
+which is smaller than or equal to 64 kilobytes, the extent of the
+buffer you receive will not cross a 64K boundary.
+
+To unmap and free such a DMA region, you call:
+
+	dma_free_coherent(dev, size, cpu_addr, dma_handle);
+
+where dev, size are the same as in the above call and cpu_addr and
+dma_handle are the values dma_alloc_coherent returned to you.
+This function may not be called in interrupt context.
+
+If your driver needs lots of smaller memory regions, you can write
+custom code to subdivide pages returned by dma_alloc_coherent,
+or you can use the dma_pool API to do that.  A dma_pool is like
+a kmem_cache, but it uses dma_alloc_coherent not __get_free_pages.
+Also, it understands common hardware constraints for alignment,
+like queue heads needing to be aligned on N byte boundaries.
+
+Create a dma_pool like this:
+
+	struct dma_pool *pool;
+
+	pool = dma_pool_create(name, dev, size, align, alloc);
+
+The "name" is for diagnostics (like a kmem_cache name); dev and size
+are as above.  The device's hardware alignment requirement for this
+type of data is "align" (which is expressed in bytes, and must be a
+power of two).  If your device has no boundary crossing restrictions,
+pass 0 for alloc; passing 4096 says memory allocated from this pool
+must not cross 4KByte boundaries (but at that time it may be better to
+go for dma_alloc_coherent directly instead).
+
+Allocate memory from a dma pool like this:
+
+	cpu_addr = dma_pool_alloc(pool, flags, &dma_handle);
+
+flags are SLAB_KERNEL if blocking is permitted (not in_interrupt nor
+holding SMP locks), SLAB_ATOMIC otherwise.  Like dma_alloc_coherent,
+this returns two values, cpu_addr and dma_handle.
+
+Free memory that was allocated from a dma_pool like this:
+
+	dma_pool_free(pool, cpu_addr, dma_handle);
+
+where pool is what you passed to dma_pool_alloc, and cpu_addr and
+dma_handle are the values dma_pool_alloc returned. This function
+may be called in interrupt context.
+
+Destroy a dma_pool by calling:
+
+	dma_pool_destroy(pool);
+
+Make sure you've called dma_pool_free for all memory allocated
+from a pool before you destroy the pool. This function may not
+be called in interrupt context.
+
+			DMA Direction
+
+The interfaces described in subsequent portions of this document
+take a DMA direction argument, which is an integer and takes on
+one of the following values:
+
+ DMA_BIDIRECTIONAL
+ DMA_TO_DEVICE
+ DMA_FROM_DEVICE
+ DMA_NONE
+
+One should provide the exact DMA direction if you know it.
+
+DMA_TO_DEVICE means "from main memory to the device"
+DMA_FROM_DEVICE means "from the device to main memory"
+It is the direction in which the data moves during the DMA
+transfer.
+
+You are _strongly_ encouraged to specify this as precisely
+as you possibly can.
+
+If you absolutely cannot know the direction of the DMA transfer,
+specify DMA_BIDIRECTIONAL.  It means that the DMA can go in
+either direction.  The platform guarantees that you may legally
+specify this, and that it will work, but this may be at the
+cost of performance for example.
+
+The value DMA_NONE is to be used for debugging.  One can
+hold this in a data structure before you come to know the
+precise direction, and this will help catch cases where your
+direction tracking logic has failed to set things up properly.
+
+Another advantage of specifying this value precisely (outside of
+potential platform-specific optimizations of such) is for debugging.
+Some platforms actually have a write permission boolean which DMA
+mappings can be marked with, much like page protections in the user
+program address space.  Such platforms can and do report errors in the
+kernel logs when the DMA controller hardware detects violation of the
+permission setting.
+
+Only streaming mappings specify a direction, consistent mappings
+implicitly have a direction attribute setting of
+DMA_BIDIRECTIONAL.
+
+The SCSI subsystem tells you the direction to use in the
+'sc_data_direction' member of the SCSI command your driver is
+working on.
+
+For Networking drivers, it's a rather simple affair.  For transmit
+packets, map/unmap them with the DMA_TO_DEVICE direction
+specifier.  For receive packets, just the opposite, map/unmap them
+with the DMA_FROM_DEVICE direction specifier.
+
+		  Using Streaming DMA mappings
+
+The streaming DMA mapping routines can be called from interrupt
+context.  There are two versions of each map/unmap, one which will
+map/unmap a single memory region, and one which will map/unmap a
+scatterlist.
+
+To map a single region, you do:
+
+	struct device *dev = &my_dev->dev;
+	dma_addr_t dma_handle;
+	void *addr = buffer->ptr;
+	size_t size = buffer->len;
+
+	dma_handle = dma_map_single(dev, addr, size, direction);
+
+and to unmap it:
+
+	dma_unmap_single(dev, dma_handle, size, direction);
+
+You should call dma_unmap_single when the DMA activity is finished, e.g.
+from the interrupt which told you that the DMA transfer is done.
+
+Using cpu pointers like this for single mappings has a disadvantage,
+you cannot reference HIGHMEM memory in this way.  Thus, there is a
+map/unmap interface pair akin to dma_{map,unmap}_single.  These
+interfaces deal with page/offset pairs instead of cpu pointers.
+Specifically:
+
+	struct device *dev = &my_dev->dev;
+	dma_addr_t dma_handle;
+	struct page *page = buffer->page;
+	unsigned long offset = buffer->offset;
+	size_t size = buffer->len;
+
+	dma_handle = dma_map_page(dev, page, offset, size, direction);
+
+	...
+
+	dma_unmap_page(dev, dma_handle, size, direction);
+
+Here, "offset" means byte offset within the given page.
+
+With scatterlists, you map a region gathered from several regions by:
+
+	int i, count = dma_map_sg(dev, sglist, nents, direction);
+	struct scatterlist *sg;
+
+	for_each_sg(sglist, sg, count, i) {
+		hw_address[i] = sg_dma_address(sg);
+		hw_len[i] = sg_dma_len(sg);
+	}
+
+where nents is the number of entries in the sglist.
+
+The implementation is free to merge several consecutive sglist entries
+into one (e.g. if DMA mapping is done with PAGE_SIZE granularity, any
+consecutive sglist entries can be merged into one provided the first one
+ends and the second one starts on a page boundary - in fact this is a huge
+advantage for cards which either cannot do scatter-gather or have very
+limited number of scatter-gather entries) and returns the actual number
+of sg entries it mapped them to. On failure 0 is returned.
+
+Then you should loop count times (note: this can be less than nents times)
+and use sg_dma_address() and sg_dma_len() macros where you previously
+accessed sg->address and sg->length as shown above.
+
+To unmap a scatterlist, just call:
+
+	dma_unmap_sg(dev, sglist, nents, direction);
+
+Again, make sure DMA activity has already finished.
+
+PLEASE NOTE:  The 'nents' argument to the dma_unmap_sg call must be
+              the _same_ one you passed into the dma_map_sg call,
+	      it should _NOT_ be the 'count' value _returned_ from the
+              dma_map_sg call.
+
+Every dma_map_{single,sg} call should have its dma_unmap_{single,sg}
+counterpart, because the bus address space is a shared resource (although
+in some ports the mapping is per each BUS so less devices contend for the
+same bus address space) and you could render the machine unusable by eating
+all bus addresses.
+
+If you need to use the same streaming DMA region multiple times and touch
+the data in between the DMA transfers, the buffer needs to be synced
+properly in order for the cpu and device to see the most uptodate and
+correct copy of the DMA buffer.
+
+So, firstly, just map it with dma_map_{single,sg}, and after each DMA
+transfer call either:
+
+	dma_sync_single_for_cpu(dev, dma_handle, size, direction);
+
+or:
+
+	dma_sync_sg_for_cpu(dev, sglist, nents, direction);
+
+as appropriate.
+
+Then, if you wish to let the device get at the DMA area again,
+finish accessing the data with the cpu, and then before actually
+giving the buffer to the hardware call either:
+
+	dma_sync_single_for_device(dev, dma_handle, size, direction);
+
+or:
+
+	dma_sync_sg_for_device(dev, sglist, nents, direction);
+
+as appropriate.
+
+After the last DMA transfer call one of the DMA unmap routines
+dma_unmap_{single,sg}. If you don't touch the data from the first dma_map_*
+call till dma_unmap_*, then you don't have to call the dma_sync_*
+routines at all.
+
+Here is pseudo code which shows a situation in which you would need
+to use the dma_sync_*() interfaces.
+
+	my_card_setup_receive_buffer(struct my_card *cp, char *buffer, int len)
+	{
+		dma_addr_t mapping;
+
+		mapping = dma_map_single(cp->dev, buffer, len, DMA_FROM_DEVICE);
+
+		cp->rx_buf = buffer;
+		cp->rx_len = len;
+		cp->rx_dma = mapping;
+
+		give_rx_buf_to_card(cp);
+	}
+
+	...
+
+	my_card_interrupt_handler(int irq, void *devid, struct pt_regs *regs)
+	{
+		struct my_card *cp = devid;
+
+		...
+		if (read_card_status(cp) == RX_BUF_TRANSFERRED) {
+			struct my_card_header *hp;
+
+			/* Examine the header to see if we wish
+			 * to accept the data.  But synchronize
+			 * the DMA transfer with the CPU first
+			 * so that we see updated contents.
+			 */
+			dma_sync_single_for_cpu(&cp->dev, cp->rx_dma,
+						cp->rx_len,
+						DMA_FROM_DEVICE);
+
+			/* Now it is safe to examine the buffer. */
+			hp = (struct my_card_header *) cp->rx_buf;
+			if (header_is_ok(hp)) {
+				dma_unmap_single(&cp->dev, cp->rx_dma, cp->rx_len,
+						 DMA_FROM_DEVICE);
+				pass_to_upper_layers(cp->rx_buf);
+				make_and_setup_new_rx_buf(cp);
+			} else {
+				/* Just sync the buffer and give it back
+				 * to the card.
+				 */
+				dma_sync_single_for_device(&cp->dev,
+							   cp->rx_dma,
+							   cp->rx_len,
+							   DMA_FROM_DEVICE);
+				give_rx_buf_to_card(cp);
+			}
+		}
+	}
+
+Drivers converted fully to this interface should not use virt_to_bus any
+longer, nor should they use bus_to_virt. Some drivers have to be changed a
+little bit, because there is no longer an equivalent to bus_to_virt in the
+dynamic DMA mapping scheme - you have to always store the DMA addresses
+returned by the dma_alloc_coherent, dma_pool_alloc, and dma_map_single
+calls (dma_map_sg stores them in the scatterlist itself if the platform
+supports dynamic DMA mapping in hardware) in your driver structures and/or
+in the card registers.
+
+All drivers should be using these interfaces with no exceptions.  It
+is planned to completely remove virt_to_bus() and bus_to_virt() as
+they are entirely deprecated.  Some ports already do not provide these
+as it is impossible to correctly support them.
+
+			Handling Errors
+
+DMA address space is limited on some architectures and an allocation
+failure can be determined by:
+
+- checking if dma_alloc_coherent returns NULL or dma_map_sg returns 0
+
+- checking the returned dma_addr_t of dma_map_single and dma_map_page
+  by using dma_mapping_error():
+
+	dma_addr_t dma_handle;
+
+	dma_handle = dma_map_single(dev, addr, size, direction);
+	if (dma_mapping_error(dev, dma_handle)) {
+		/*
+		 * reduce current DMA mapping usage,
+		 * delay and try again later or
+		 * reset driver.
+		 */
+	}
+
+Networking drivers must call dev_kfree_skb to free the socket buffer
+and return NETDEV_TX_OK if the DMA mapping fails on the transmit hook
+(ndo_start_xmit). This means that the socket buffer is just dropped in
+the failure case.
+
+SCSI drivers must return SCSI_MLQUEUE_HOST_BUSY if the DMA mapping
+fails in the queuecommand hook. This means that the SCSI subsystem
+passes the command to the driver again later.
+
+		Optimizing Unmap State Space Consumption
+
+On many platforms, dma_unmap_{single,page}() is simply a nop.
+Therefore, keeping track of the mapping address and length is a waste
+of space.  Instead of filling your drivers up with ifdefs and the like
+to "work around" this (which would defeat the whole purpose of a
+portable API) the following facilities are provided.
+
+Actually, instead of describing the macros one by one, we'll
+transform some example code.
+
+1) Use DEFINE_DMA_UNMAP_{ADDR,LEN} in state saving structures.
+   Example, before:
+
+	struct ring_state {
+		struct sk_buff *skb;
+		dma_addr_t mapping;
+		__u32 len;
+	};
+
+   after:
+
+	struct ring_state {
+		struct sk_buff *skb;
+		DEFINE_DMA_UNMAP_ADDR(mapping);
+		DEFINE_DMA_UNMAP_LEN(len);
+	};
+
+2) Use dma_unmap_{addr,len}_set to set these values.
+   Example, before:
+
+	ringp->mapping = FOO;
+	ringp->len = BAR;
+
+   after:
+
+	dma_unmap_addr_set(ringp, mapping, FOO);
+	dma_unmap_len_set(ringp, len, BAR);
+
+3) Use dma_unmap_{addr,len} to access these values.
+   Example, before:
+
+	dma_unmap_single(dev, ringp->mapping, ringp->len,
+			 DMA_FROM_DEVICE);
+
+   after:
+
+	dma_unmap_single(dev,
+			 dma_unmap_addr(ringp, mapping),
+			 dma_unmap_len(ringp, len),
+			 DMA_FROM_DEVICE);
+
+It really should be self-explanatory.  We treat the ADDR and LEN
+separately, because it is possible for an implementation to only
+need the address in order to perform the unmap operation.
+
+			Platform Issues
+
+If you are just writing drivers for Linux and do not maintain
+an architecture port for the kernel, you can safely skip down
+to "Closing".
+
+1) Struct scatterlist requirements.
+
+   Don't invent the architecture specific struct scatterlist; just use
+   <asm-generic/scatterlist.h>. You need to enable
+   CONFIG_NEED_SG_DMA_LENGTH if the architecture supports IOMMUs
+   (including software IOMMU).
+
+2) ARCH_KMALLOC_MINALIGN
+
+   Architectures must ensure that kmalloc'ed buffer is
+   DMA-safe. Drivers and subsystems depend on it. If an architecture
+   isn't fully DMA-coherent (i.e. hardware doesn't ensure that data in
+   the CPU cache is identical to data in main memory),
+   ARCH_KMALLOC_MINALIGN must be set so that the memory allocator
+   makes sure that kmalloc'ed buffer doesn't share a cache line with
+   the others. See arch/arm/include/asm/cache.h as an example.
+
+   Note that ARCH_KMALLOC_MINALIGN is about DMA memory alignment
+   constraints. You don't need to worry about the architecture data
+   alignment constraints (e.g. the alignment constraints about 64-bit
+   objects).
+
+			   Closing
+
+This document, and the API itself, would not be in its current
+form without the feedback and suggestions from numerous individuals.
+We would like to specifically mention, in no particular order, the
+following people:
+
+	Russell King <rmk@arm.linux.org.uk>
+	Leo Dagum <dagum@barrel.engr.sgi.com>
+	Ralf Baechle <ralf@oss.sgi.com>
+	Grant Grundler <grundler@cup.hp.com>
+	Jay Estabrook <Jay.Estabrook@compaq.com>
+	Thomas Sailer <sailer@ife.ee.ethz.ch>
+	Andrea Arcangeli <andrea@suse.de>
+	Jens Axboe <jens.axboe@oracle.com>
+	David Mosberger-Tang <davidm@hpl.hp.com>

Documentation/DocBook/Makefile

@@ -14,7 +14,7 @@ DOCBOOKS := z8530book.xml mcabook.xml device-drivers.xml \
 	    genericirq.xml s390-drivers.xml uio-howto.xml scsi.xml \
 	    mac80211.xml debugobjects.xml sh.xml regulator.xml \
 	    alsa-driver-api.xml writing-an-alsa-driver.xml \
-	    tracepoint.xml media.xml
+	    tracepoint.xml media.xml drm.xml
 
 ###
 # The build process is as follows (targets):

Documentation/DocBook/drm.tmpl

@@ -0,0 +1,839 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
+	"http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" []>
+
+<book id="drmDevelopersGuide">
+  <bookinfo>
+    <title>Linux DRM Developer's Guide</title>
+
+    <copyright>
+      <year>2008-2009</year>
+      <holder>
+	Intel Corporation (Jesse Barnes &lt;jesse.barnes@intel.com&gt;)
+      </holder>
+    </copyright>
+
+    <legalnotice>
+      <para>
+	The contents of this file may be used under the terms of the GNU
+	General Public License version 2 (the "GPL") as distributed in
+	the kernel source COPYING file.
+      </para>
+    </legalnotice>
+  </bookinfo>
+
+<toc></toc>
+
+  <!-- Introduction -->
+
+  <chapter id="drmIntroduction">
+    <title>Introduction</title>
+    <para>
+      The Linux DRM layer contains code intended to support the needs
+      of complex graphics devices, usually containing programmable
+      pipelines well suited to 3D graphics acceleration.  Graphics
+      drivers in the kernel can make use of DRM functions to make
+      tasks like memory management, interrupt handling and DMA easier,
+      and provide a uniform interface to applications.
+    </para>
+    <para>
+      A note on versions: this guide covers features found in the DRM
+      tree, including the TTM memory manager, output configuration and
+      mode setting, and the new vblank internals, in addition to all
+      the regular features found in current kernels.
+    </para>
+    <para>
+      [Insert diagram of typical DRM stack here]
+    </para>
+  </chapter>
+
+  <!-- Internals -->
+
+  <chapter id="drmInternals">
+    <title>DRM Internals</title>
+    <para>
+      This chapter documents DRM internals relevant to driver authors
+      and developers working to add support for the latest features to
+      existing drivers.
+    </para>
+    <para>
+      First, we'll go over some typical driver initialization
+      requirements, like setting up command buffers, creating an
+      initial output configuration, and initializing core services.
+      Subsequent sections will cover core internals in more detail,
+      providing implementation notes and examples.
+    </para>
+    <para>
+      The DRM layer provides several services to graphics drivers,
+      many of them driven by the application interfaces it provides
+      through libdrm, the library that wraps most of the DRM ioctls.
+      These include vblank event handling, memory
+      management, output management, framebuffer management, command
+      submission &amp; fencing, suspend/resume support, and DMA
+      services.
+    </para>
+    <para>
+      The core of every DRM driver is struct drm_device.  Drivers
+      will typically statically initialize a drm_device structure,
+      then pass it to drm_init() at load time.
+    </para>
+
+  <!-- Internals: driver init -->
+
+  <sect1>
+    <title>Driver initialization</title>
+    <para>
+      Before calling the DRM initialization routines, the driver must
+      first create and fill out a struct drm_device structure.
+    </para>
+    <programlisting>
+      static struct drm_driver driver = {
+	/* don't use mtrr's here, the Xserver or user space app should
+	 * deal with them for intel hardware.
+	 */
+	.driver_features =
+	    DRIVER_USE_AGP | DRIVER_REQUIRE_AGP |
+	    DRIVER_HAVE_IRQ | DRIVER_IRQ_SHARED | DRIVER_MODESET,
+	.load = i915_driver_load,
+	.unload = i915_driver_unload,
+	.firstopen = i915_driver_firstopen,
+	.lastclose = i915_driver_lastclose,
+	.preclose = i915_driver_preclose,
+	.save = i915_save,
+	.restore = i915_restore,
+	.device_is_agp = i915_driver_device_is_agp,
+	.get_vblank_counter = i915_get_vblank_counter,
+	.enable_vblank = i915_enable_vblank,
+	.disable_vblank = i915_disable_vblank,
+	.irq_preinstall = i915_driver_irq_preinstall,
+	.irq_postinstall = i915_driver_irq_postinstall,
+	.irq_uninstall = i915_driver_irq_uninstall,
+	.irq_handler = i915_driver_irq_handler,
+	.reclaim_buffers = drm_core_reclaim_buffers,
+	.get_map_ofs = drm_core_get_map_ofs,
+	.get_reg_ofs = drm_core_get_reg_ofs,
+	.fb_probe = intelfb_probe,
+	.fb_remove = intelfb_remove,
+	.fb_resize = intelfb_resize,
+	.master_create = i915_master_create,
+	.master_destroy = i915_master_destroy,
+#if defined(CONFIG_DEBUG_FS)
+	.debugfs_init = i915_debugfs_init,
+	.debugfs_cleanup = i915_debugfs_cleanup,
+#endif
+	.gem_init_object = i915_gem_init_object,
+	.gem_free_object = i915_gem_free_object,
+	.gem_vm_ops = &amp;i915_gem_vm_ops,
+	.ioctls = i915_ioctls,
+	.fops = {
+		.owner = THIS_MODULE,
+		.open = drm_open,
+		.release = drm_release,
+		.ioctl = drm_ioctl,
+		.mmap = drm_mmap,
+		.poll = drm_poll,
+		.fasync = drm_fasync,
+#ifdef CONFIG_COMPAT
+		.compat_ioctl = i915_compat_ioctl,
+#endif
+		},
+	.pci_driver = {
+		.name = DRIVER_NAME,
+		.id_table = pciidlist,
+		.probe = probe,
+		.remove = __devexit_p(drm_cleanup_pci),
+		},
+	.name = DRIVER_NAME,
+	.desc = DRIVER_DESC,
+	.date = DRIVER_DATE,
+	.major = DRIVER_MAJOR,
+	.minor = DRIVER_MINOR,
+	.patchlevel = DRIVER_PATCHLEVEL,
+      };
+    </programlisting>
+    <para>
+      In the example above, taken from the i915 DRM driver, the driver
+      sets several flags indicating what core features it supports.
+      We'll go over the individual callbacks in later sections.  Since
+      flags indicate which features your driver supports to the DRM
+      core, you need to set most of them prior to calling drm_init().  Some,
+      like DRIVER_MODESET can be set later based on user supplied parameters,
+      but that's the exception rather than the rule.
+    </para>
+    <variablelist>
+      <title>Driver flags</title>
+      <varlistentry>
+	<term>DRIVER_USE_AGP</term>
+	<listitem><para>
+	    Driver uses AGP interface
+	</para></listitem>
+      </varlistentry>
+      <varlistentry>
+	<term>DRIVER_REQUIRE_AGP</term>
+	<listitem><para>
+	    Driver needs AGP interface to function.
+	</para></listitem>
+      </varlistentry>
+      <varlistentry>
+	<term>DRIVER_USE_MTRR</term>
+	<listitem>
+	  <para>
+	    Driver uses MTRR interface for mapping memory.  Deprecated.
+	  </para>
+	</listitem>
+      </varlistentry>
+      <varlistentry>
+	<term>DRIVER_PCI_DMA</term>
+	<listitem><para>
+	    Driver is capable of PCI DMA.  Deprecated.
+	</para></listitem>
+      </varlistentry>
+      <varlistentry>
+	<term>DRIVER_SG</term>
+	<listitem><para>
+	    Driver can perform scatter/gather DMA.  Deprecated.
+	</para></listitem>
+      </varlistentry>
+      <varlistentry>
+	<term>DRIVER_HAVE_DMA</term>
+	<listitem><para>Driver supports DMA.  Deprecated.</para></listitem>
+      </varlistentry>
+      <varlistentry>
+	<term>DRIVER_HAVE_IRQ</term><term>DRIVER_IRQ_SHARED</term>
+	<listitem>
+	  <para>
+	    DRIVER_HAVE_IRQ indicates whether the driver has a IRQ
+	    handler, DRIVER_IRQ_SHARED indicates whether the device &amp;
+	    handler support shared IRQs (note that this is required of
+	    PCI drivers).
+	  </para>
+	</listitem>
+      </varlistentry>
+      <varlistentry>
+	<term>DRIVER_DMA_QUEUE</term>
+	<listitem>
+	  <para>
+	    If the driver queues DMA requests and completes them
+	    asynchronously, this flag should be set.  Deprecated.
+	  </para>
+	</listitem>
+      </varlistentry>
+      <varlistentry>
+	<term>DRIVER_FB_DMA</term>
+	<listitem>
+	  <para>
+	    Driver supports DMA to/from the framebuffer.  Deprecated.
+	  </para>
+	</listitem>
+      </varlistentry>
+      <varlistentry>
+	<term>DRIVER_MODESET</term>
+	<listitem>
+	  <para>
+	    Driver supports mode setting interfaces.
+	  </para>
+	</listitem>
+      </varlistentry>
+    </variablelist>
+    <para>
+      In this specific case, the driver requires AGP and supports
+      IRQs.  DMA, as we'll see, is handled by device specific ioctls
+      in this case.  It also supports the kernel mode setting APIs, though
+      unlike in the actual i915 driver source, this example unconditionally
+      exports KMS capability.
+    </para>
+  </sect1>
+
+  <!-- Internals: driver load -->
+
+  <sect1>
+    <title>Driver load</title>
+    <para>
+      In the previous section, we saw what a typical drm_driver
+      structure might look like.  One of the more important fields in
+      the structure is the hook for the load function.
+    </para>
+    <programlisting>
+      static struct drm_driver driver = {
+      	...
+      	.load = i915_driver_load,
+        ...
+      };
+    </programlisting>
+    <para>
+      The load function has many responsibilities: allocating a driver
+      private structure, specifying supported performance counters,
+      configuring the device (e.g. mapping registers &amp; command
+      buffers), initializing the memory manager, and setting up the
+      initial output configuration.
+    </para>
+    <para>
+      Note that the tasks performed at driver load time must not
+      conflict with DRM client requirements.  For instance, if user
+      level mode setting drivers are in use, it would be problematic
+      to perform output discovery &amp; configuration at load time.
+      Likewise, if pre-memory management aware user level drivers are
+      in use, memory management and command buffer setup may need to
+      be omitted.  These requirements are driver specific, and care
+      needs to be taken to keep both old and new applications and
+      libraries working.  The i915 driver supports the "modeset"
+      module parameter to control whether advanced features are
+      enabled at load time or in legacy fashion.  If compatibility is
+      a concern (e.g. with drivers converted over to the new interfaces
+      from the old ones), care must be taken to prevent incompatible
+      device initialization and control with the currently active
+      userspace drivers.
+    </para>
+
+    <sect2>
+      <title>Driver private &amp; performance counters</title>
+      <para>
+	The driver private hangs off the main drm_device structure and
+	can be used for tracking various device specific bits of
+	information, like register offsets, command buffer status,
+	register state for suspend/resume, etc.  At load time, a
+	driver can simply allocate one and set drm_device.dev_priv
+	appropriately; at unload the driver can free it and set
+	drm_device.dev_priv to NULL.
+      </para>
+      <para>
+	The DRM supports several counters which can be used for rough
+	performance characterization.  Note that the DRM stat counter
+	system is not often used by applications, and supporting
+	additional counters is completely optional.
+      </para>
+      <para>
+	These interfaces are deprecated and should not be used.  If performance
+	monitoring is desired, the developer should investigate and
+	potentially enhance the kernel perf and tracing infrastructure to export
+	GPU related performance information to performance monitoring
+	tools and applications.
+      </para>
+    </sect2>
+
+    <sect2>
+      <title>Configuring the device</title>
+      <para>
+	Obviously, device configuration will be device specific.
+	However, there are several common operations: finding a
+	device's PCI resources, mapping them, and potentially setting
+	up an IRQ handler.
+      </para>
+      <para>
+	Finding &amp; mapping resources is fairly straightforward.  The
+	DRM wrapper functions, drm_get_resource_start() and
+	drm_get_resource_len() can be used to find BARs on the given
+	drm_device struct.  Once those values have been retrieved, the
+	driver load function can call drm_addmap() to create a new
+	mapping for the BAR in question.  Note you'll probably want a
+	drm_local_map_t in your driver private structure to track any
+	mappings you create.
+<!-- !Fdrivers/gpu/drm/drm_bufs.c drm_get_resource_* -->
+<!-- !Finclude/drm/drmP.h drm_local_map_t -->
+      </para>
+      <para>
+	if compatibility with other operating systems isn't a concern
+	(DRM drivers can run under various BSD variants and OpenSolaris),
+	native Linux calls can be used for the above, e.g. pci_resource_*
+	and iomap*/iounmap.  See the Linux device driver book for more
+	info.
+      </para>
+      <para>
+	Once you have a register map, you can use the DRM_READn() and
+	DRM_WRITEn() macros to access the registers on your device, or
+	use driver specific versions to offset into your MMIO space
+	relative to a driver specific base pointer (see I915_READ for
+	example).
+      </para>
+      <para>
+	If your device supports interrupt generation, you may want to
+	setup an interrupt handler at driver load time as well.  This
+	is done using the drm_irq_install() function.  If your device
+	supports vertical blank interrupts, it should call
+	drm_vblank_init() to initialize the core vblank handling code before
+	enabling interrupts on your device.  This ensures the vblank related
+	structures are allocated and allows the core to handle vblank events.
+      </para>
+<!--!Fdrivers/char/drm/drm_irq.c drm_irq_install-->
+      <para>
+	Once your interrupt handler is registered (it'll use your
+	drm_driver.irq_handler as the actual interrupt handling
+	function), you can safely enable interrupts on your device,
+	assuming any other state your interrupt handler uses is also
+	initialized.
+      </para>
+      <para>
+	Another task that may be necessary during configuration is
+	mapping the video BIOS.  On many devices, the VBIOS describes
+	device configuration, LCD panel timings (if any), and contains
+	flags indicating device state.  Mapping the BIOS can be done
+	using the pci_map_rom() call, a convenience function that
+	takes care of mapping the actual ROM, whether it has been
+	shadowed into memory (typically at address 0xc0000) or exists
+	on the PCI device in the ROM BAR.  Note that once you've
+	mapped the ROM and extracted any necessary information, be
+	sure to unmap it; on many devices the ROM address decoder is
+	shared with other BARs, so leaving it mapped can cause
+	undesired behavior like hangs or memory corruption.
+<!--!Fdrivers/pci/rom.c pci_map_rom-->
+      </para>
+    </sect2>
+
+    <sect2>
+      <title>Memory manager initialization</title>
+      <para>
+	In order to allocate command buffers, cursor memory, scanout
+	buffers, etc., as well as support the latest features provided
+	by packages like Mesa and the X.Org X server, your driver
+	should support a memory manager.
+      </para>
+      <para>
+	If your driver supports memory management (it should!), you'll
+	need to set that up at load time as well.  How you intialize
+	it depends on which memory manager you're using, TTM or GEM.
+      </para>
+      <sect3>
+	<title>TTM initialization</title>
+	<para>
+	  TTM (for Translation Table Manager) manages video memory and
+	  aperture space for graphics devices. TTM supports both UMA devices
+	  and devices with dedicated video RAM (VRAM), i.e. most discrete
+	  graphics devices.  If your device has dedicated RAM, supporting
+	  TTM is desireable.  TTM also integrates tightly with your
+	  driver specific buffer execution function.  See the radeon
+	  driver for examples.
+	</para>
+	<para>
+	  The core TTM structure is the ttm_bo_driver struct.  It contains
+	  several fields with function pointers for initializing the TTM,
+	  allocating and freeing memory, waiting for command completion
+	  and fence synchronization, and memory migration.  See the
+	  radeon_ttm.c file for an example of usage.
+	</para>
+	<para>
+	  The ttm_global_reference structure is made up of several fields:
+	</para>
+	<programlisting>
+	  struct ttm_global_reference {
+	  	enum ttm_global_types global_type;
+	  	size_t size;
+	  	void *object;
+	  	int (*init) (struct ttm_global_reference *);
+	  	void (*release) (struct ttm_global_reference *);
+	  };
+	</programlisting>
+	<para>
+	  There should be one global reference structure for your memory
+	  manager as a whole, and there will be others for each object
+	  created by the memory manager at runtime.  Your global TTM should
+	  have a type of TTM_GLOBAL_TTM_MEM.  The size field for the global
+	  object should be sizeof(struct ttm_mem_global), and the init and
+	  release hooks should point at your driver specific init and
+	  release routines, which will probably eventually call
+	  ttm_mem_global_init and ttm_mem_global_release respectively.
+	</para>
+	<para>
+	  Once your global TTM accounting structure is set up and initialized
+	  (done by calling ttm_global_item_ref on the global object you
+	  just created), you'll need to create a buffer object TTM to
+	  provide a pool for buffer object allocation by clients and the
+	  kernel itself.  The type of this object should be TTM_GLOBAL_TTM_BO,
+	  and its size should be sizeof(struct ttm_bo_global).  Again,
+	  driver specific init and release functions can be provided,
+	  likely eventually calling ttm_bo_global_init and
+	  ttm_bo_global_release, respectively.  Also like the previous
+	  object, ttm_global_item_ref is used to create an initial reference
+	  count for the TTM, which will call your initalization function.
+	</para>
+      </sect3>
+      <sect3>
+	<title>GEM initialization</title>
+	<para>
+	  GEM is an alternative to TTM, designed specifically for UMA
+	  devices.  It has simpler initialization and execution requirements
+	  than TTM, but has no VRAM management capability.  Core GEM
+	  initialization is comprised of a basic drm_mm_init call to create
+	  a GTT DRM MM object, which provides an address space pool for
+	  object allocation.  In a KMS configuration, the driver will
+	  need to allocate and initialize a command ring buffer following
+	  basic GEM initialization.  Most UMA devices have a so-called
+	  "stolen" memory region, which provides space for the initial
+	  framebuffer and large, contiguous memory regions required by the
+	  device.  This space is not typically managed by GEM, and must
+	  be initialized separately into its own DRM MM object.
+	</para>
+	<para>
+	  Initialization will be driver specific, and will depend on
+	  the architecture of the device.  In the case of Intel
+	  integrated graphics chips like 965GM, GEM initialization can
+	  be done by calling the internal GEM init function,
+	  i915_gem_do_init().  Since the 965GM is a UMA device
+	  (i.e. it doesn't have dedicated VRAM), GEM will manage
+	  making regular RAM available for GPU operations.  Memory set
+	  aside by the BIOS (called "stolen" memory by the i915
+	  driver) will be managed by the DRM memrange allocator; the
+	  rest of the aperture will be managed by GEM.
+	  <programlisting>
+	    /* Basic memrange allocator for stolen space (aka vram) */
+	    drm_memrange_init(&amp;dev_priv->vram, 0, prealloc_size);
+	    /* Let GEM Manage from end of prealloc space to end of aperture */
+	    i915_gem_do_init(dev, prealloc_size, agp_size);
+	  </programlisting>
+<!--!Edrivers/char/drm/drm_memrange.c-->
+	</para>
+	<para>
+	  Once the memory manager has been set up, we can allocate the
+	  command buffer.  In the i915 case, this is also done with a
+	  GEM function, i915_gem_init_ringbuffer().
+	</para>
+      </sect3>
+    </sect2>
+
+    <sect2>
+      <title>Output configuration</title>
+      <para>
+	The final initialization task is output configuration.  This involves
+	finding and initializing the CRTCs, encoders and connectors
+	for your device, creating an initial configuration and
+	registering a framebuffer console driver.
+      </para>
+      <sect3>
+	<title>Output discovery and initialization</title>
+	<para>
+	  Several core functions exist to create CRTCs, encoders and
+	  connectors, namely drm_crtc_init(), drm_connector_init() and
+	  drm_encoder_init(), along with several "helper" functions to
+	  perform common tasks.
+	</para>
+	<para>
+	  Connectors should be registered with sysfs once they've been
+	  detected and initialized, using the
+	  drm_sysfs_connector_add() function.  Likewise, when they're
+	  removed from the system, they should be destroyed with
+	  drm_sysfs_connector_remove().
+	</para>
+	<programlisting>
+<![CDATA[
+void intel_crt_init(struct drm_device *dev)
+{
+	struct drm_connector *connector;
+	struct intel_output *intel_output;
+
+	intel_output = kzalloc(sizeof(struct intel_output), GFP_KERNEL);
+	if (!intel_output)
+		return;
+
+	connector = &intel_output->base;
+	drm_connector_init(dev, &intel_output->base,
+			   &intel_crt_connector_funcs, DRM_MODE_CONNECTOR_VGA);
+
+	drm_encoder_init(dev, &intel_output->enc, &intel_crt_enc_funcs,
+			 DRM_MODE_ENCODER_DAC);
+
+	drm_mode_connector_attach_encoder(&intel_output->base,
+					  &intel_output->enc);
+
+	/* Set up the DDC bus. */
+	intel_output->ddc_bus = intel_i2c_create(dev, GPIOA, "CRTDDC_A");
+	if (!intel_output->ddc_bus) {
+		dev_printk(KERN_ERR, &dev->pdev->dev, "DDC bus registration "
+			   "failed.\n");
+		return;
+	}
+
+	intel_output->type = INTEL_OUTPUT_ANALOG;
+	connector->interlace_allowed = 0;
+	connector->doublescan_allowed = 0;
+
+	drm_encoder_helper_add(&intel_output->enc, &intel_crt_helper_funcs);
+	drm_connector_helper_add(connector, &intel_crt_connector_helper_funcs);
+
+	drm_sysfs_connector_add(connector);
+}
+]]>
+	</programlisting>
+	<para>
+	  In the example above (again, taken from the i915 driver), a
+	  CRT connector and encoder combination is created.  A device
+	  specific i2c bus is also created, for fetching EDID data and
+	  performing monitor detection.  Once the process is complete,
+	  the new connector is regsitered with sysfs, to make its
+	  properties available to applications.
+	</para>
+	<sect4>
+	  <title>Helper functions and core functions</title>
+	  <para>
+	    Since many PC-class graphics devices have similar display output
+	    designs, the DRM provides a set of helper functions to make
+	    output management easier.  The core helper routines handle
+	    encoder re-routing and disabling of unused functions following
+	    mode set.  Using the helpers is optional, but recommended for
+	    devices with PC-style architectures (i.e. a set of display planes
+	    for feeding pixels to encoders which are in turn routed to
+	    connectors).  Devices with more complex requirements needing
+	    finer grained management can opt to use the core callbacks
+	    directly.
+	  </para>
+	  <para>
+	    [Insert typical diagram here.]  [Insert OMAP style config here.]
+	  </para>
+	</sect4>
+	<para>
+	  For each encoder, CRTC and connector, several functions must
+	  be provided, depending on the object type.  Encoder objects
+	  need should provide a DPMS (basically on/off) function, mode fixup
+	  (for converting requested modes into native hardware timings),
+	  and prepare, set and commit functions for use by the core DRM
+	  helper functions.  Connector helpers need to provide mode fetch and
+	  validity functions as well as an encoder matching function for
+	  returing an ideal encoder for a given connector.  The core
+	  connector functions include a DPMS callback, (deprecated)
+	  save/restore routines, detection, mode probing, property handling,
+	  and cleanup functions.
+	</para>
+<!--!Edrivers/char/drm/drm_crtc.h-->
+<!--!Edrivers/char/drm/drm_crtc.c-->
+<!--!Edrivers/char/drm/drm_crtc_helper.c-->
+      </sect3>
+    </sect2>
+  </sect1>
+
+  <!-- Internals: vblank handling -->
+
+  <sect1>
+    <title>VBlank event handling</title>
+    <para>
+      The DRM core exposes two vertical blank related ioctls:
+      DRM_IOCTL_WAIT_VBLANK and DRM_IOCTL_MODESET_CTL.
+<!--!Edrivers/char/drm/drm_irq.c-->
+    </para>
+    <para>
+      DRM_IOCTL_WAIT_VBLANK takes a struct drm_wait_vblank structure
+      as its argument, and is used to block or request a signal when a
+      specified vblank event occurs.
+    </para>
+    <para>
+      DRM_IOCTL_MODESET_CTL should be called by application level
+      drivers before and after mode setting, since on many devices the
+      vertical blank counter will be reset at that time.  Internally,
+      the DRM snapshots the last vblank count when the ioctl is called
+      with the _DRM_PRE_MODESET command so that the counter won't go
+      backwards (which is dealt with when _DRM_POST_MODESET is used).
+    </para>
+    <para>
+      To support the functions above, the DRM core provides several
+      helper functions for tracking vertical blank counters, and
+      requires drivers to provide several callbacks:
+      get_vblank_counter(), enable_vblank() and disable_vblank().  The
+      core uses get_vblank_counter() to keep the counter accurate
+      across interrupt disable periods.  It should return the current
+      vertical blank event count, which is often tracked in a device
+      register.  The enable and disable vblank callbacks should enable
+      and disable vertical blank interrupts, respectively.  In the
+      absence of DRM clients waiting on vblank events, the core DRM
+      code will use the disable_vblank() function to disable
+      interrupts, which saves power.  They'll be re-enabled again when
+      a client calls the vblank wait ioctl above.
+    </para>
+    <para>
+      Devices that don't provide a count register can simply use an
+      internal atomic counter incremented on every vertical blank
+      interrupt, and can make their enable and disable vblank
+      functions into no-ops.
+    </para>
+  </sect1>
+
+  <sect1>
+    <title>Memory management</title>
+    <para>
+      The memory manager lies at the heart of many DRM operations, and
+      is also required to support advanced client features like OpenGL
+      pbuffers.  The DRM currently contains two memory managers, TTM
+      and GEM.
+    </para>
+
+    <sect2>
+      <title>The Translation Table Manager (TTM)</title>
+      <para>
+	TTM was developed by Tungsten Graphics, primarily by Thomas
+	Hellström, and is intended to be a flexible, high performance
+	graphics memory manager.
+      </para>
+      <para>
+	Drivers wishing to support TTM must fill out a drm_bo_driver
+	structure.
+      </para>
+      <para>
+	TTM design background and information belongs here.
+      </para>
+    </sect2>
+
+    <sect2>
+      <title>The Graphics Execution Manager (GEM)</title>
+      <para>
+	GEM is an Intel project, authored by Eric Anholt and Keith
+	Packard.  It provides simpler interfaces than TTM, and is well
+	suited for UMA devices.
+      </para>
+      <para>
+	GEM-enabled drivers must provide gem_init_object() and
+	gem_free_object() callbacks to support the core memory
+	allocation routines.  They should also provide several driver
+	specific ioctls to support command execution, pinning, buffer
+	read &amp; write, mapping, and domain ownership transfers.
+      </para>
+      <para>
+	On a fundamental level, GEM involves several operations: memory
+	allocation and freeing, command execution, and aperture management
+	at command execution time.  Buffer object allocation is relatively
+	straightforward and largely provided by Linux's shmem layer, which
+	provides memory to back each object.  When mapped into the GTT
+	or used in a command buffer, the backing pages for an object are
+	flushed to memory and marked write combined so as to be coherent
+	with the GPU.  Likewise, when the GPU finishes rendering to an object,
+	if the CPU accesses it, it must be made coherent with the CPU's view
+	of memory, usually involving GPU cache flushing of various kinds.
+	This core CPU&lt;-&gt;GPU coherency management is provided by the GEM
+	set domain function, which evaluates an object's current domain and
+	performs any necessary flushing or synchronization to put the object
+	into the desired coherency domain (note that the object may be busy,
+	i.e. an active render target; in that case the set domain function
+	will block the client and wait for rendering to complete before
+	performing any necessary flushing operations).
+      </para>
+      <para>
+	Perhaps the most important GEM function is providing a command
+	execution interface to clients.  Client programs construct command
+	buffers containing references to previously allocated memory objects
+	and submit them to GEM.  At that point, GEM will take care to bind
+	all the objects into the GTT, execute the buffer, and provide
+	necessary synchronization between clients accessing the same buffers.
+	This often involves evicting some objects from the GTT and re-binding
+	others (a fairly expensive operation), and providing relocation
+	support which hides fixed GTT offsets from clients.  Clients must
+	take care not to submit command buffers that reference more objects
+	than can fit in the GTT or GEM will reject them and no rendering
+	will occur.  Similarly, if several objects in the buffer require
+	fence registers to be allocated for correct rendering (e.g. 2D blits
+	on pre-965 chips), care must be taken not to require more fence
+	registers than are available to the client.  Such resource management
+	should be abstracted from the client in libdrm.
+      </para>
+    </sect2>
+
+  </sect1>
+
+  <!-- Output management -->
+  <sect1>
+    <title>Output management</title>
+    <para>
+      At the core of the DRM output management code is a set of
+      structures representing CRTCs, encoders and connectors.
+    </para>
+    <para>
+      A CRTC is an abstraction representing a part of the chip that
+      contains a pointer to a scanout buffer.  Therefore, the number
+      of CRTCs available determines how many independent scanout
+      buffers can be active at any given time.  The CRTC structure
+      contains several fields to support this: a pointer to some video
+      memory, a display mode, and an (x, y) offset into the video
+      memory to support panning or configurations where one piece of
+      video memory spans multiple CRTCs.
+    </para>
+    <para>
+      An encoder takes pixel data from a CRTC and converts it to a
+      format suitable for any attached connectors.  On some devices,
+      it may be possible to have a CRTC send data to more than one
+      encoder.  In that case, both encoders would receive data from
+      the same scanout buffer, resulting in a "cloned" display
+      configuration across the connectors attached to each encoder.
+    </para>
+    <para>
+      A connector is the final destination for pixel data on a device,
+      and usually connects directly to an external display device like
+      a monitor or laptop panel.  A connector can only be attached to
+      one encoder at a time.  The connector is also the structure
+      where information about the attached display is kept, so it
+      contains fields for display data, EDID data, DPMS &amp;
+      connection status, and information about modes supported on the
+      attached displays.
+    </para>
+<!--!Edrivers/char/drm/drm_crtc.c-->
+  </sect1>
+
+  <sect1>
+    <title>Framebuffer management</title>
+    <para>
+      In order to set a mode on a given CRTC, encoder and connector
+      configuration, clients need to provide a framebuffer object which
+      will provide a source of pixels for the CRTC to deliver to the encoder(s)
+      and ultimately the connector(s) in the configuration.  A framebuffer
+      is fundamentally a driver specific memory object, made into an opaque
+      handle by the DRM addfb function.  Once an fb has been created this
+      way it can be passed to the KMS mode setting routines for use in
+      a configuration.
+    </para>
+  </sect1>
+
+  <sect1>
+    <title>Command submission &amp; fencing</title>
+    <para>
+      This should cover a few device specific command submission
+      implementations.
+    </para>
+  </sect1>
+
+  <sect1>
+    <title>Suspend/resume</title>
+    <para>
+      The DRM core provides some suspend/resume code, but drivers
+      wanting full suspend/resume support should provide save() and
+      restore() functions.  These will be called at suspend,
+      hibernate, or resume time, and should perform any state save or
+      restore required by your device across suspend or hibernate
+      states.
+    </para>
+  </sect1>
+
+  <sect1>
+    <title>DMA services</title>
+    <para>
+      This should cover how DMA mapping etc. is supported by the core.
+      These functions are deprecated and should not be used.
+    </para>
+  </sect1>
+  </chapter>
+
+  <!-- External interfaces -->
+
+  <chapter id="drmExternals">
+    <title>Userland interfaces</title>
+    <para>
+      The DRM core exports several interfaces to applications,
+      generally intended to be used through corresponding libdrm
+      wrapper functions.  In addition, drivers export device specific
+      interfaces for use by userspace drivers &amp; device aware
+      applications through ioctls and sysfs files.
+    </para>
+    <para>
+      External interfaces include: memory mapping, context management,
+      DMA operations, AGP management, vblank control, fence
+      management, memory management, and output management.
+    </para>
+    <para>
+      Cover generic ioctls and sysfs layout here.  Only need high
+      level info, since man pages will cover the rest.
+    </para>
+  </chapter>
+
+  <!-- API reference -->
+
+  <appendix id="drmDriverApi">
+    <title>DRM Driver API</title>
+    <para>
+      Include auto-generated API reference here (need to reference it
+      from paragraphs above too).
+    </para>
+  </appendix>
+
+</book>

Documentation/DocBook/kgdb.tmpl

@@ -4,7 +4,7 @@
 
 <book id="kgdbOnLinux">
  <bookinfo>
-  <title>Using kgdb and the kgdb Internals</title>
+  <title>Using kgdb, kdb and the kernel debugger internals</title>
 
   <authorgroup>
    <author>
@@ -17,33 +17,8 @@
     </affiliation>
    </author>
   </authorgroup>
-
-  <authorgroup>
-   <author>
-    <firstname>Tom</firstname>
-    <surname>Rini</surname>
-    <affiliation>
-     <address>
-      <email>trini@kernel.crashing.org</email>
-     </address>
-    </affiliation>
-   </author>
-  </authorgroup>
-
-  <authorgroup>
-   <author>
-    <firstname>Amit S.</firstname>
-    <surname>Kale</surname>
-    <affiliation>
-     <address>
-      <email>amitkale@linsyssoft.com</email>
-     </address>
-    </affiliation>
-   </author>
-  </authorgroup>
-
   <copyright>
-   <year>2008</year>
+   <year>2008,2010</year>
    <holder>Wind River Systems, Inc.</holder>
   </copyright>
   <copyright>
@@ -69,41 +44,76 @@
   <chapter id="Introduction">
     <title>Introduction</title>
     <para>
-    kgdb is a source level debugger for linux kernel. It is used along
-    with gdb to debug a linux kernel.  The expectation is that gdb can
-    be used to "break in" to the kernel to inspect memory, variables
-    and look through call stack information similar to what an
-    application developer would use gdb for.  It is possible to place
-    breakpoints in kernel code and perform some limited execution
-    stepping.
+    The kernel has two different debugger front ends (kdb and kgdb)
+    which interface to the debug core.  It is possible to use either
+    of the debugger front ends and dynamically transition between them
+    if you configure the kernel properly at compile and runtime.
+    </para>
+    <para>
+    Kdb is simplistic shell-style interface which you can use on a
+    system console with a keyboard or serial console.  You can use it
+    to inspect memory, registers, process lists, dmesg, and even set
+    breakpoints to stop in a certain location.  Kdb is not a source
+    level debugger, although you can set breakpoints and execute some
+    basic kernel run control.  Kdb is mainly aimed at doing some
+    analysis to aid in development or diagnosing kernel problems.  You
+    can access some symbols by name in kernel built-ins or in kernel
+    modules if the code was built
+    with <symbol>CONFIG_KALLSYMS</symbol>.
+    </para>
+    <para>
+    Kgdb is intended to be used as a source level debugger for the
+    Linux kernel. It is used along with gdb to debug a Linux kernel.
+    The expectation is that gdb can be used to "break in" to the
+    kernel to inspect memory, variables and look through call stack
+    information similar to the way an application developer would use
+    gdb to debug an application.  It is possible to place breakpoints
+    in kernel code and perform some limited execution stepping.
     </para>
     <para>
-    Two machines are required for using kgdb. One of these machines is a
-    development machine and the other is a test machine.  The kernel
-    to be debugged runs on the test machine. The development machine
-    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.  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.
+    Two machines are required for using kgdb. One of these machines is
+    a development machine and the other is the target machine.  The
+    kernel to be debugged runs on the target machine. The development
+    machine 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.  The type of connection a
+    developer makes with gdb depends on the availability of kgdb I/O
+    modules compiled as built-ins or loadable kernel modules in the test
+    machine's kernel.
     </para>
   </chapter>
   <chapter id="CompilingAKernel">
-    <title>Compiling a kernel</title>
+  <title>Compiling a kernel</title>
+  <para>
+  <itemizedlist>
+  <listitem><para>In order to enable compilation of kdb, you must first enable kgdb.</para></listitem>
+  <listitem><para>The kgdb test compile options are described in the kgdb test suite chapter.</para></listitem>
+  </itemizedlist>
+  </para>
+  <sect1 id="CompileKGDB">
+    <title>Kernel config options for kgdb</title>
     <para>
     To enable <symbol>CONFIG_KGDB</symbol> you should first turn on
     "Prompt for development and/or incomplete code/drivers"
     (CONFIG_EXPERIMENTAL) in  "General setup", then under the
-    "Kernel debugging" select "KGDB: kernel debugging with remote gdb".
+    "Kernel debugging" select "KGDB: kernel debugger".
+    </para>
+    <para>
+    While it is not a hard requirement that you have symbols in your
+    vmlinux file, gdb tends not to be very useful without the symbolic
+    data, so you will want to turn
+    on <symbol>CONFIG_DEBUG_INFO</symbol> which is called "Compile the
+    kernel with debug info" in the config menu.
     </para>
     <para>
     It is advised, but not required that you turn on the
-    CONFIG_FRAME_POINTER kernel option.  This option inserts code to
-    into the compiled executable which saves the frame information in
-    registers or on the stack at different points which will allow a
-    debugger such as gdb to more accurately construct stack back traces
-    while debugging the kernel.
+    <symbol>CONFIG_FRAME_POINTER</symbol> kernel option which is called "Compile the
+    kernel with frame pointers" in the config menu.  This option
+    inserts code to into the compiled executable which saves the frame
+    information in registers or on the stack at different points which
+    allows a debugger such as gdb to more accurately construct
+    stack back traces while debugging the kernel.
     </para>
     <para>
     If the architecture that you are using supports the kernel option
@@ -116,38 +126,160 @@
     this option.
     </para>
     <para>
-    Next you should choose one of more I/O drivers to interconnect debugging
-    host and debugged target.  Early boot debugging requires a KGDB
-    I/O driver that supports early debugging and the driver must be
-    built into the kernel directly. Kgdb I/O driver configuration
-    takes place via kernel or module parameters, see following
-    chapter.
+    Next you should choose one of more I/O drivers to interconnect
+    debugging host and debugged target.  Early boot debugging requires
+    a KGDB I/O driver that supports early debugging and the driver
+    must be built into the kernel directly. Kgdb I/O driver
+    configuration takes place via kernel or module parameters which
+    you can learn more about in the in the section that describes the
+    parameter "kgdboc".
     </para>
-    <para>
-    The kgdb test compile options are described in the kgdb test suite chapter.
+    <para>Here is an example set of .config symbols to enable or
+    disable for kgdb:
+    <itemizedlist>
+    <listitem><para># CONFIG_DEBUG_RODATA is not set</para></listitem>
+    <listitem><para>CONFIG_FRAME_POINTER=y</para></listitem>
+    <listitem><para>CONFIG_KGDB=y</para></listitem>
+    <listitem><para>CONFIG_KGDB_SERIAL_CONSOLE=y</para></listitem>
+    </itemizedlist>
     </para>
-
+  </sect1>
+  <sect1 id="CompileKDB">
+    <title>Kernel config options for kdb</title>
+    <para>Kdb is quite a bit more complex than the simple gdbstub
+    sitting on top of the kernel's debug core.  Kdb must implement a
+    shell, and also adds some helper functions in other parts of the
+    kernel, responsible for printing out interesting data such as what
+    you would see if you ran "lsmod", or "ps".  In order to build kdb
+    into the kernel you follow the same steps as you would for kgdb.
+    </para>
+    <para>The main config option for kdb
+    is <symbol>CONFIG_KGDB_KDB</symbol> which is called "KGDB_KDB:
+    include kdb frontend for kgdb" in the config menu.  In theory you
+    would have already also selected an I/O driver such as the
+    CONFIG_KGDB_SERIAL_CONSOLE interface if you plan on using kdb on a
+    serial port, when you were configuring kgdb.
+    </para>
+    <para>If you want to use a PS/2-style keyboard with kdb, you would
+    select CONFIG_KDB_KEYBOARD which is called "KGDB_KDB: keyboard as
+    input device" in the config menu.  The CONFIG_KDB_KEYBOARD option
+    is not used for anything in the gdb interface to kgdb.  The
+    CONFIG_KDB_KEYBOARD option only works with kdb.
+    </para>
+    <para>Here is an example set of .config symbols to enable/disable kdb:
+    <itemizedlist>
+    <listitem><para># CONFIG_DEBUG_RODATA is not set</para></listitem>
+    <listitem><para>CONFIG_FRAME_POINTER=y</para></listitem>
+    <listitem><para>CONFIG_KGDB=y</para></listitem>
+    <listitem><para>CONFIG_KGDB_SERIAL_CONSOLE=y</para></listitem>
+    <listitem><para>CONFIG_KGDB_KDB=y</para></listitem>
+    <listitem><para>CONFIG_KDB_KEYBOARD=y</para></listitem>
+    </itemizedlist>
+    </para>
+  </sect1>
   </chapter>
-  <chapter id="EnableKGDB">
-   <title>Enable kgdb for debugging</title>
-   <para>
-   In order to use kgdb you must activate it by passing configuration
-   information to one of the kgdb I/O drivers.  If you do not pass any
-   configuration information kgdb will not do anything at all.  Kgdb
-   will only actively hook up to the kernel trap hooks if a kgdb I/O
-   driver is loaded and configured.  If you unconfigure a kgdb I/O
-   driver, kgdb will unregister all the kernel hook points.
+  <chapter id="kgdbKernelArgs">
+  <title>Kernel Debugger Boot Arguments</title>
+  <para>This section describes the various runtime kernel
+  parameters that affect the configuration of the kernel debugger.
+  The following chapter covers using kdb and kgdb as well as
+  provides some examples of the configuration parameters.</para>
+   <sect1 id="kgdboc">
+   <title>Kernel parameter: kgdboc</title>
+   <para>The kgdboc driver was originally an abbreviation meant to
+   stand for "kgdb over console".  Today it is the primary mechanism
+   to configure how to communicate from gdb to kgdb as well as the
+   devices you want to use to interact with the kdb shell.
+   </para>
+   <para>For kgdb/gdb, kgdboc is designed to work with a single serial
+   port. It is intended to cover the circumstance where you want to
+   use a serial console as your primary console as well as using it to
+   perform kernel debugging.  It is also possible to use kgdb on a
+   serial port which is not designated as a system console.  Kgdboc
+   may be configured as a kernel built-in or a kernel loadable module.
+   You can only make use of <constant>kgdbwait</constant> and early
+   debugging if you build kgdboc into the kernel as a built-in.
    </para>
+   <sect2 id="kgdbocArgs">
+   <title>kgdboc arguments</title>
+   <para>Usage: <constant>kgdboc=[kbd][[,]serial_device][,baud]</constant></para>
+   <sect3 id="kgdbocArgs1">
+   <title>Using loadable module or built-in</title>
    <para>
-   All drivers can be reconfigured at run time, if
-   <symbol>CONFIG_SYSFS</symbol> and <symbol>CONFIG_MODULES</symbol>
-   are enabled, by echo'ing a new config string to
-   <constant>/sys/module/&lt;driver&gt;/parameter/&lt;option&gt;</constant>.
-   The driver can be unconfigured by passing an empty string.  You cannot
-   change the configuration while the debugger is attached.  Make sure
-   to detach the debugger with the <constant>detach</constant> command
-   prior to trying unconfigure a kgdb I/O driver.
+   <orderedlist>
+   <listitem><para>As a kernel built-in:</para>
+   <para>Use the kernel boot argument: <constant>kgdboc=&lt;tty-device&gt;,[baud]</constant></para></listitem>
+   <listitem>
+   <para>As a kernel loadable module:</para>
+   <para>Use the command: <constant>modprobe kgdboc kgdboc=&lt;tty-device&gt;,[baud]</constant></para>
+   <para>Here are two examples of how you might formate the kgdboc
+   string. The first is for an x86 target using the first serial port.
+   The second example is for the ARM Versatile AB using the second
+   serial port.
+   <orderedlist>
+   <listitem><para><constant>kgdboc=ttyS0,115200</constant></para></listitem>
+   <listitem><para><constant>kgdboc=ttyAMA1,115200</constant></para></listitem>
+   </orderedlist>
    </para>
+   </listitem>
+   </orderedlist></para>
+   </sect3>
+   <sect3 id="kgdbocArgs2">
+   <title>Configure kgdboc at runtime with sysfs</title>
+   <para>At run time you can enable or disable kgdboc by echoing a
+   parameters into the sysfs.  Here are two examples:</para>
+   <orderedlist>
+   <listitem><para>Enable kgdboc on ttyS0</para>
+   <para><constant>echo ttyS0 &gt; /sys/module/kgdboc/parameters/kgdboc</constant></para></listitem>
+   <listitem><para>Disable kgdboc</para>
+   <para><constant>echo "" &gt; /sys/module/kgdboc/parameters/kgdboc</constant></para></listitem>
+   </orderedlist>
+   <para>NOTE: You do not need to specify the baud if you are
+   configuring the console on tty which is already configured or
+   open.</para>
+   </sect3>
+   <sect3 id="kgdbocArgs3">
+   <title>More examples</title>
+   <para>You can configure kgdboc to use the keyboard, and or a serial device
+   depending on if you are using kdb and or kgdb, in one of the
+   following scenarios.
+   <orderedlist>
+   <listitem><para>kdb and kgdb over only a serial port</para>
+   <para><constant>kgdboc=&lt;serial_device&gt;[,baud]</constant></para>
+   <para>Example: <constant>kgdboc=ttyS0,115200</constant></para>
+   </listitem>
+   <listitem><para>kdb and kgdb with keyboard and a serial port</para>
+   <para><constant>kgdboc=kbd,&lt;serial_device&gt;[,baud]</constant></para>
+   <para>Example: <constant>kgdboc=kbd,ttyS0,115200</constant></para>
+   </listitem>
+   <listitem><para>kdb with a keyboard</para>
+   <para><constant>kgdboc=kbd</constant></para>
+   </listitem>
+   </orderedlist>
+   </para>
+   </sect3>
+   <para>NOTE: Kgdboc does not support interrupting the target via the
+   gdb remote protocol.  You must manually send a sysrq-g unless you
+   have a proxy that splits console output to a terminal program.
+   A console proxy has a separate TCP port for the debugger and a separate
+   TCP port for the "human" console.  The proxy can take care of sending
+   the sysrq-g for you.
+   </para>
+   <para>When using kgdboc with no debugger proxy, you can end up
+    connecting the debugger at one of two entry points.  If an
+    exception occurs after you have loaded kgdboc, a message should
+    print on the console stating it is waiting for the debugger.  In
+    this case you disconnect your terminal program and then connect the
+    debugger in its place.  If you want to interrupt the target system
+    and forcibly enter a debug session you have to issue a Sysrq
+    sequence and then type the letter <constant>g</constant>.  Then
+    you disconnect the terminal session and connect gdb.  Your options
+    if you don't like this are to hack gdb to send the sysrq-g for you
+    as well as on the initial connect, or to use a debugger proxy that
+    allows an unmodified gdb to do the debugging.
+   </para>
+   </sect2>
+   </sect1>
    <sect1 id="kgdbwait">
    <title>Kernel parameter: kgdbwait</title>
    <para>
@@ -162,103 +294,204 @@
    </para>
    <para>
    The kernel will stop and wait as early as the I/O driver and
-   architecture will allow when you use this option.  If you build the
-   kgdb I/O driver as a kernel module kgdbwait will not do anything.
+   architecture allows when you use this option.  If you build the
+   kgdb I/O driver as a loadable kernel module kgdbwait will not do
+   anything.
    </para>
    </sect1>
-  <sect1 id="kgdboc">
-  <title>Kernel parameter: kgdboc</title>
-  <para>
-  The kgdboc driver was originally an abbreviation meant to stand for
-  "kgdb over console".  Kgdboc is designed to work with a single
-  serial port. It was meant to cover the circumstance
-  where you wanted to use a serial console as your primary console as
-  well as using it to perform kernel debugging.  Of course you can
-  also use kgdboc without assigning a console to the same port.
+   <sect1 id="kgdbcon">
+   <title>Kernel parameter: kgdbcon</title>
+   <para> The kgdbcon feature allows you to see printk() messages
+   inside gdb while gdb is connected to the kernel.  Kdb does not make
+    use of the kgdbcon feature.
+   </para>
+   <para>Kgdb supports using the gdb serial protocol to send console
+   messages to the debugger when the debugger is connected and running.
+   There are two ways to activate this feature.
+   <orderedlist>
+   <listitem><para>Activate with the kernel command line option:</para>
+   <para><constant>kgdbcon</constant></para>
+   </listitem>
+   <listitem><para>Use sysfs before configuring an I/O driver</para>
+   <para>
+   <constant>echo 1 &gt; /sys/module/kgdb/parameters/kgdb_use_con</constant>
+   </para>
+   <para>
+   NOTE: If you do this after you configure the kgdb I/O driver, the
+   setting will not take effect until the next point the I/O is
+   reconfigured.
+   </para>
+   </listitem>
+   </orderedlist>
+   <para>IMPORTANT NOTE: You cannot use kgdboc + kgdbcon on a tty that is an
+   active system console.  An example incorrect usage is <constant>console=ttyS0,115200 kgdboc=ttyS0 kgdbcon</constant>
+   </para>
+   <para>It is possible to use this option with kgdboc on a tty that is not a system console.
+   </para>
   </para>
-  <sect2 id="UsingKgdboc">
-  <title>Using kgdboc</title>
-  <para>
-  You can configure kgdboc via sysfs or a module or kernel boot line
-  parameter depending on if you build with CONFIG_KGDBOC as a module
-  or built-in.
-  <orderedlist>
-  <listitem><para>From the module load or build-in</para>
-  <para><constant>kgdboc=&lt;tty-device&gt;,[baud]</constant></para>
+  </sect1>
+  </chapter>
+  <chapter id="usingKDB">
+  <title>Using kdb</title>
   <para>
-  The example here would be if your console port was typically ttyS0, you would use something like <constant>kgdboc=ttyS0,115200</constant> or on the ARM Versatile AB you would likely use <constant>kgdboc=ttyAMA0,115200</constant>
+  </para>
+  <sect1 id="quickKDBserial">
+  <title>Quick start for kdb on a serial port</title>
+  <para>This is a quick example of how to use kdb.</para>
+  <para><orderedlist>
+  <listitem><para>Boot kernel with arguments:
+  <itemizedlist>
+  <listitem><para><constant>console=ttyS0,115200 kgdboc=ttyS0,115200</constant></para></listitem>
+  </itemizedlist></para>
+  <para>OR</para>
+  <para>Configure kgdboc after the kernel booted; assuming you are using a serial port console:
+  <itemizedlist>
+  <listitem><para><constant>echo ttyS0 &gt; /sys/module/kgdboc/parameters/kgdboc</constant></para></listitem>
+  </itemizedlist>
   </para>
   </listitem>
-  <listitem><para>From sysfs</para>
-  <para><constant>echo ttyS0 &gt; /sys/module/kgdboc/parameters/kgdboc</constant></para>
+  <listitem><para>Enter the kernel debugger manually or by waiting for an oops or fault.  There are several ways you can enter the kernel debugger manually; all involve using the sysrq-g, which means you must have enabled CONFIG_MAGIC_SYSRQ=y in your kernel config.</para>
+  <itemizedlist>
+  <listitem><para>When logged in as root or with a super user session you can run:</para>
+   <para><constant>echo g &gt; /proc/sysrq-trigger</constant></para></listitem>
+  <listitem><para>Example using minicom 2.2</para>
+  <para>Press: <constant>Control-a</constant></para>
+  <para>Press: <constant>f</constant></para>
+  <para>Press: <constant>g</constant></para>
   </listitem>
-  </orderedlist>
-  </para>
-  <para>
-  NOTE: Kgdboc does not support interrupting the target via the
-  gdb remote protocol.  You must manually send a sysrq-g unless you
-  have a proxy that splits console output to a terminal problem and
-  has a separate port for the debugger to connect to that sends the
-  sysrq-g for you.
+  <listitem><para>When you have telneted to a terminal server that supports sending a remote break</para>
+  <para>Press: <constant>Control-]</constant></para>
+  <para>Type in:<constant>send break</constant></para>
+  <para>Press: <constant>Enter</constant></para>
+  <para>Press: <constant>g</constant></para>
+  </listitem>
+  </itemizedlist>
+  </listitem>
+  <listitem><para>From the kdb prompt you can run the "help" command to see a complete list of the commands that are available.</para>
+  <para>Some useful commands in kdb include:
+  <itemizedlist>
+  <listitem><para>lsmod  -- Shows where kernel modules are loaded</para></listitem>
+  <listitem><para>ps -- Displays only the active processes</para></listitem>
+  <listitem><para>ps A -- Shows all the processes</para></listitem>
+  <listitem><para>summary -- Shows kernel version info and memory usage</para></listitem>
+  <listitem><para>bt -- Get a backtrace of the current process using dump_stack()</para></listitem>
+  <listitem><para>dmesg -- View the kernel syslog buffer</para></listitem>
+  <listitem><para>go -- Continue the system</para></listitem>
+  </itemizedlist>
   </para>
-  <para>When using kgdboc with no debugger proxy, you can end up
-  connecting the debugger for one of two entry points.  If an
-  exception occurs after you have loaded kgdboc a message should print
-  on the console stating it is waiting for the debugger.  In case you
-  disconnect your terminal program and then connect the debugger in
-  its place.  If you want to interrupt the target system and forcibly
-  enter a debug session you have to issue a Sysrq sequence and then
-  type the letter <constant>g</constant>.  Then you disconnect the
-  terminal session and connect gdb.  Your options if you don't like
-  this are to hack gdb to send the sysrq-g for you as well as on the
-  initial connect, or to use a debugger proxy that allows an
-  unmodified gdb to do the debugging.
+  </listitem>
+  <listitem>
+  <para>When you are done using kdb you need to consider rebooting the
+  system or using the "go" command to resuming normal kernel
+  execution.  If you have paused the kernel for a lengthy period of
+  time, applications that rely on timely networking or anything to do
+  with real wall clock time could be adversely affected, so you
+  should take this into consideration when using the kernel
+  debugger.</para>
+  </listitem>
+  </orderedlist></para>
+  </sect1>
+  <sect1 id="quickKDBkeyboard">
+  <title>Quick start for kdb using a keyboard connected console</title>
+  <para>This is a quick example of how to use kdb with a keyboard.</para>
+  <para><orderedlist>
+  <listitem><para>Boot kernel with arguments:
+  <itemizedlist>
+  <listitem><para><constant>kgdboc=kbd</constant></para></listitem>
+  </itemizedlist></para>
+  <para>OR</para>
+  <para>Configure kgdboc after the kernel booted:
+  <itemizedlist>
+  <listitem><para><constant>echo kbd &gt; /sys/module/kgdboc/parameters/kgdboc</constant></para></listitem>
+  </itemizedlist>
   </para>
-  </sect2>
+  </listitem>
+  <listitem><para>Enter the kernel debugger manually or by waiting for an oops or fault.  There are several ways you can enter the kernel debugger manually; all involve using the sysrq-g, which means you must have enabled CONFIG_MAGIC_SYSRQ=y in your kernel config.</para>
+  <itemizedlist>
+  <listitem><para>When logged in as root or with a super user session you can run:</para>
+   <para><constant>echo g &gt; /proc/sysrq-trigger</constant></para></listitem>
+  <listitem><para>Example using a laptop keyboard</para>
+  <para>Press and hold down: <constant>Alt</constant></para>
+  <para>Press and hold down: <constant>Fn</constant></para>
+  <para>Press and release the key with the label: <constant>SysRq</constant></para>
+  <para>Release: <constant>Fn</constant></para>
+  <para>Press and release: <constant>g</constant></para>
+  <para>Release: <constant>Alt</constant></para>
+  </listitem>
+  <listitem><para>Example using a PS/2 101-key keyboard</para>
+  <para>Press and hold down: <constant>Alt</constant></para>
+  <para>Press and release the key with the label: <constant>SysRq</constant></para>
+  <para>Press and release: <constant>g</constant></para>
+  <para>Release: <constant>Alt</constant></para>
+  </listitem>
+  </itemizedlist>
+  </listitem>
+  <listitem>
+  <para>Now type in a kdb command such as "help", "dmesg", "bt" or "go" to continue kernel execution.</para>
+  </listitem>
+  </orderedlist></para>
   </sect1>
-  <sect1 id="kgdbcon">
-  <title>Kernel parameter: kgdbcon</title>
-  <para>
-  Kgdb supports using the gdb serial protocol to send console messages
-  to the debugger when the debugger is connected and running.  There
-  are two ways to activate this feature.
+  </chapter>
+  <chapter id="EnableKGDB">
+   <title>Using kgdb / gdb</title>
+   <para>In order to use kgdb you must activate it by passing
+   configuration information to one of the kgdb I/O drivers.  If you
+   do not pass any configuration information kgdb will not do anything
+   at all.  Kgdb will only actively hook up to the kernel trap hooks
+   if a kgdb I/O driver is loaded and configured.  If you unconfigure
+   a kgdb I/O driver, kgdb will unregister all the kernel hook points.
+   </para>
+   <para> All kgdb I/O drivers can be reconfigured at run time, if
+   <symbol>CONFIG_SYSFS</symbol> and <symbol>CONFIG_MODULES</symbol>
+   are enabled, by echo'ing a new config string to
+   <constant>/sys/module/&lt;driver&gt;/parameter/&lt;option&gt;</constant>.
+   The driver can be unconfigured by passing an empty string.  You cannot
+   change the configuration while the debugger is attached.  Make sure
+   to detach the debugger with the <constant>detach</constant> command
+   prior to trying to unconfigure a kgdb I/O driver.
+   </para>
+  <sect1 id="ConnectingGDB">
+  <title>Connecting with gdb to a serial port</title>
   <orderedlist>
-  <listitem><para>Activate with the kernel command line option:</para>
-  <para><constant>kgdbcon</constant></para>
+  <listitem><para>Configure kgdboc</para>
+   <para>Boot kernel with arguments:
+   <itemizedlist>
+    <listitem><para><constant>kgdboc=ttyS0,115200</constant></para></listitem>
+   </itemizedlist></para>
+   <para>OR</para>
+   <para>Configure kgdboc after the kernel booted:
+   <itemizedlist>
+    <listitem><para><constant>echo ttyS0 &gt; /sys/module/kgdboc/parameters/kgdboc</constant></para></listitem>
+   </itemizedlist></para>
   </listitem>
-  <listitem><para>Use sysfs before configuring an io driver</para>
-  <para>
-  <constant>echo 1 &gt; /sys/module/kgdb/parameters/kgdb_use_con</constant>
-  </para>
-  <para>
-  NOTE: If you do this after you configure the kgdb I/O driver, the
-  setting will not take effect until the next point the I/O is
-  reconfigured.
-  </para>
+  <listitem>
+  <para>Stop kernel execution (break into the debugger)</para>
+  <para>In order to connect to gdb via kgdboc, the kernel must
+  first be stopped.  There are several ways to stop the kernel which
+  include using kgdbwait as a boot argument, via a sysrq-g, or running
+  the kernel until it takes an exception where it waits for the
+  debugger to attach.
+  <itemizedlist>
+  <listitem><para>When logged in as root or with a super user session you can run:</para>
+   <para><constant>echo g &gt; /proc/sysrq-trigger</constant></para></listitem>
+  <listitem><para>Example using minicom 2.2</para>
+  <para>Press: <constant>Control-a</constant></para>
+  <para>Press: <constant>f</constant></para>
+  <para>Press: <constant>g</constant></para>
   </listitem>
-  </orderedlist>
-  </para>
-  <para>
-  IMPORTANT NOTE: Using this option with kgdb over the console
-  (kgdboc) is not supported.
+  <listitem><para>When you have telneted to a terminal server that supports sending a remote break</para>
+  <para>Press: <constant>Control-]</constant></para>
+  <para>Type in:<constant>send break</constant></para>
+  <para>Press: <constant>Enter</constant></para>
+  <para>Press: <constant>g</constant></para>
+  </listitem>
+  </itemizedlist>
   </para>
-  </sect1>
-  </chapter>
-  <chapter id="ConnectingGDB">
-  <title>Connecting gdb</title>
-    <para>
-    If you are using kgdboc, you need to have used kgdbwait as a boot
-    argument, issued a sysrq-g, or the system you are going to debug
-    has already taken an exception and is waiting for the debugger to
-    attach before you can connect gdb.
-    </para>
-    <para>
-    If you are not using different kgdb I/O driver other than kgdboc,
-    you should be able to connect and the target will automatically
-    respond.
-    </para>
+  </listitem>
+  <listitem>
+    <para>Connect from from gdb</para>
     <para>
-    Example (using a serial port):
+    Example (using a directly connected port):
     </para>
     <programlisting>
     % gdb ./vmlinux
@@ -266,7 +499,7 @@
     (gdb) target remote /dev/ttyS0
     </programlisting>
     <para>
-    Example (kgdb to a terminal server on tcp port 2012):
+    Example (kgdb to a terminal server on TCP port 2012):
     </para>
     <programlisting>
     % gdb ./vmlinux
@@ -283,6 +516,83 @@
     communications.  You do this prior to issuing the <constant>target
     remote</constant> command by typing in: <constant>set debug remote 1</constant>
     </para>
+  </listitem>
+  </orderedlist>
+  <para>Remember if you continue in gdb, and need to "break in" again,
+  you need to issue an other sysrq-g.  It is easy to create a simple
+  entry point by putting a breakpoint at <constant>sys_sync</constant>
+  and then you can run "sync" from a shell or script to break into the
+  debugger.</para>
+  </sect1>
+  </chapter>
+  <chapter id="switchKdbKgdb">
+  <title>kgdb and kdb interoperability</title>
+  <para>It is possible to transition between kdb and kgdb dynamically.
+  The debug core will remember which you used the last time and
+  automatically start in the same mode.</para>
+  <sect1>
+  <title>Switching between kdb and kgdb</title>
+  <sect2>
+  <title>Switching from kgdb to kdb</title>
+  <para>
+  There are two ways to switch from kgdb to kdb: you can use gdb to
+  issue a maintenance packet, or you can blindly type the command $3#33.
+  Whenever kernel debugger stops in kgdb mode it will print the
+  message <constant>KGDB or $3#33 for KDB</constant>.  It is important
+  to note that you have to type the sequence correctly in one pass.
+  You cannot type a backspace or delete because kgdb will interpret
+  that as part of the debug stream.
+  <orderedlist>
+  <listitem><para>Change from kgdb to kdb by blindly typing:</para>
+  <para><constant>$3#33</constant></para></listitem>
+  <listitem><para>Change from kgdb to kdb with gdb</para>
+  <para><constant>maintenance packet 3</constant></para>
+  <para>NOTE: Now you must kill gdb. Typically you press control-z and
+  issue the command: kill -9 %</para></listitem>
+  </orderedlist>
+  </para>
+  </sect2>
+  <sect2>
+  <title>Change from kdb to kgdb</title>
+  <para>There are two ways you can change from kdb to kgdb.  You can
+  manually enter kgdb mode by issuing the kgdb command from the kdb
+  shell prompt, or you can connect gdb while the kdb shell prompt is
+  active.  The kdb shell looks for the typical first commands that gdb
+  would issue with the gdb remote protocol and if it sees one of those
+  commands it automatically changes into kgdb mode.</para>
+  <orderedlist>
+  <listitem><para>From kdb issue the command:</para>
+  <para><constant>kgdb</constant></para>
+  <para>Now disconnect your terminal program and connect gdb in its place</para></listitem>
+  <listitem><para>At the kdb prompt, disconnect the terminal program and connect gdb in its place.</para></listitem>
+  </orderedlist>
+  </sect2>
+  </sect1>
+  <sect1>
+  <title>Running kdb commands from gdb</title>
+  <para>It is possible to run a limited set of kdb commands from gdb,
+  using the gdb monitor command.  You don't want to execute any of the
+  run control or breakpoint operations, because it can disrupt the
+  state of the kernel debugger.  You should be using gdb for
+  breakpoints and run control operations if you have gdb connected.
+  The more useful commands to run are things like lsmod, dmesg, ps or
+  possibly some of the memory information commands.  To see all the kdb
+  commands you can run <constant>monitor help</constant>.</para>
+  <para>Example:
+  <informalexample><programlisting>
+(gdb) monitor ps
+1 idle process (state I) and
+27 sleeping system daemon (state M) processes suppressed,
+use 'ps A' to see all.
+Task Addr       Pid   Parent [*] cpu State Thread     Command
+
+0xc78291d0        1        0  0    0   S  0xc7829404  init
+0xc7954150      942        1  0    0   S  0xc7954384  dropbear
+0xc78789c0      944        1  0    0   S  0xc7878bf4  sh
+(gdb)
+  </programlisting></informalexample>
+  </para>
+  </sect1>
   </chapter>
   <chapter id="KGDBTestSuite">
     <title>kgdb Test Suite</title>
@@ -309,34 +619,36 @@
     </para>
   </chapter>
   <chapter id="CommonBackEndReq">
-  <title>KGDB Internals</title>
+  <title>Kernel Debugger Internals</title>
   <sect1 id="kgdbArchitecture">
     <title>Architecture Specifics</title>
       <para>
-      Kgdb is organized into three basic components:
+      The kernel debugger is organized into a number of components:
       <orderedlist>
-      <listitem><para>kgdb core</para>
+      <listitem><para>The debug core</para>
       <para>
-      The kgdb core is found in kernel/kgdb.c.  It contains:
+      The debug core is found in kernel/debugger/debug_core.c.  It contains:
       <itemizedlist>
-      <listitem><para>All the logic to implement the gdb serial protocol</para></listitem>
-      <listitem><para>A generic OS exception handler which includes sync'ing the processors into a stopped state on an multi cpu system.</para></listitem>
+      <listitem><para>A generic OS exception handler which includes
+      sync'ing the processors into a stopped state on an multi-CPU
+      system.</para></listitem>
       <listitem><para>The API to talk to the kgdb I/O drivers</para></listitem>
-      <listitem><para>The API to make calls to the arch specific kgdb implementation</para></listitem>
+      <listitem><para>The API to make calls to the arch-specific kgdb implementation</para></listitem>
       <listitem><para>The logic to perform safe memory reads and writes to memory while using the debugger</para></listitem>
       <listitem><para>A full implementation for software breakpoints unless overridden by the arch</para></listitem>
+      <listitem><para>The API to invoke either the kdb or kgdb frontend to the debug core.</para></listitem>
       </itemizedlist>
       </para>
       </listitem>
-      <listitem><para>kgdb arch specific implementation</para>
+      <listitem><para>kgdb arch-specific implementation</para>
       <para>
       This implementation is generally found in arch/*/kernel/kgdb.c.
       As an example, arch/x86/kernel/kgdb.c contains the specifics to
       implement HW breakpoint as well as the initialization to
       dynamically register and unregister for the trap handlers on
-      this architecture.  The arch specific portion implements:
+      this architecture.  The arch-specific portion implements:
       <itemizedlist>
-      <listitem><para>contains an arch specific trap catcher which
+      <listitem><para>contains an arch-specific trap catcher which
       invokes kgdb_handle_exception() to start kgdb about doing its
       work</para></listitem>
       <listitem><para>translation to and from gdb specific packet format to pt_regs</para></listitem>
@@ -347,11 +659,35 @@
       </itemizedlist>
       </para>
       </listitem>
+      <listitem><para>gdbstub frontend (aka kgdb)</para>
+      <para>The gdbstub is located in kernel/debug/gdbstub.c. It contains:</para>
+      <itemizedlist>
+        <listitem><para>All the logic to implement the gdb serial protocol</para></listitem>
+      </itemizedlist>
+      </listitem>
+      <listitem><para>kdb frontend</para>
+      <para>The kdb debugger shell is broken down into a number of
+      components.  The kdb core is located in kernel/debug/kdb.  There
+      are a number of helper functions in some of the other kernel
+      components to make it possible for kdb to examine and report
+      information about the kernel without taking locks that could
+      cause a kernel deadlock.  The kdb core contains implements the following functionality.</para>
+      <itemizedlist>
+        <listitem><para>A simple shell</para></listitem>
+        <listitem><para>The kdb core command set</para></listitem>
+        <listitem><para>A registration API to register additional kdb shell commands.</para>
+        <para>A good example of a self-contained kdb module is the "ftdump" command for dumping the ftrace buffer.  See: kernel/trace/trace_kdb.c</para></listitem>
+        <listitem><para>The implementation for kdb_printf() which
+        emits messages directly to I/O drivers, bypassing the kernel
+        log.</para></listitem>
+        <listitem><para>SW / HW breakpoint management for the kdb shell</para></listitem>
+      </itemizedlist>
+      </listitem>
       <listitem><para>kgdb I/O driver</para>
       <para>
-      Each kgdb I/O driver has to provide an implemenation for the following:
+      Each kgdb I/O driver has to provide an implementation for the following:
       <itemizedlist>
-      <listitem><para>configuration via builtin or module</para></listitem>
+      <listitem><para>configuration via built-in or module</para></listitem>
       <listitem><para>dynamic configuration and kgdb hook registration calls</para></listitem>
       <listitem><para>read and write character interface</para></listitem>
       <listitem><para>A cleanup handler for unconfiguring from the kgdb core</para></listitem>
@@ -416,15 +752,15 @@
   underlying low level to the hardware driver having "polling hooks"
   which the to which the tty driver is attached.  In the initial
   implementation of kgdboc it the serial_core was changed to expose a
-  low level uart hook for doing polled mode reading and writing of a
+  low level UART hook for doing polled mode reading and writing of a
   single character while in an atomic context.  When kgdb makes an I/O
   request to the debugger, kgdboc invokes a call back in the serial
-  core which in turn uses the call back in the uart driver.  It is
-  certainly possible to extend kgdboc to work with non-uart based
+  core which in turn uses the call back in the UART driver.  It is
+  certainly possible to extend kgdboc to work with non-UART based
   consoles in the future.
   </para>
   <para>
-  When using kgdboc with a uart, the uart driver must implement two callbacks in the <constant>struct uart_ops</constant>. Example from drivers/8250.c:<programlisting>
+  When using kgdboc with a UART, the UART driver must implement two callbacks in the <constant>struct uart_ops</constant>. Example from drivers/8250.c:<programlisting>
 #ifdef CONFIG_CONSOLE_POLL
 	.poll_get_char = serial8250_get_poll_char,
 	.poll_put_char = serial8250_put_poll_char,
@@ -434,7 +770,7 @@
   <constant>#ifdef CONFIG_CONSOLE_POLL</constant>, as shown above.
   Keep in mind that polling hooks have to be implemented in such a way
   that they can be called from an atomic context and have to restore
-  the state of the uart chip on return such that the system can return
+  the state of the UART chip on return such that the system can return
   to normal when the debugger detaches.  You need to be very careful
   with any kind of lock you consider, because failing here is most
   going to mean pressing the reset button.
@@ -453,6 +789,10 @@
 		<itemizedlist>
 		<listitem><para>Jason Wessel<email>jason.wessel@windriver.com</email></para></listitem>
 		</itemizedlist>
+                In Jan 2010 this document was updated to include kdb.
+		<itemizedlist>
+		<listitem><para>Jason Wessel<email>jason.wessel@windriver.com</email></para></listitem>
+		</itemizedlist>
 	</para>
   </chapter>
 </book>

Documentation/DocBook/libata.tmpl

@@ -81,16 +81,14 @@ void (*port_disable) (struct ata_port *);
 	</programlisting>
 
 	<para>
-	Called from ata_bus_probe() and ata_bus_reset() error paths,
-	as well as when unregistering from the SCSI module (rmmod, hot
-	unplug).
+	Called from ata_bus_probe() error path, as well as when
+	unregistering from the SCSI module (rmmod, hot unplug).
 	This function should do whatever needs to be done to take the
 	port out of use.  In most cases, ata_port_disable() can be used
 	as this hook.
 	</para>
 	<para>
 	Called from ata_bus_probe() on a failed probe.
-	Called from ata_bus_reset() on a failed bus reset.
 	Called from ata_scsi_release().
 	</para>
 
@@ -107,10 +105,6 @@ void (*dev_config) (struct ata_port *, struct ata_device *);
 	issue of SET FEATURES - XFER MODE, and prior to operation.
 	</para>
 	<para>
-	Called by ata_device_add() after ata_dev_identify() determines
-	a device is present.
-	</para>
-	<para>
 	This entry may be specified as NULL in ata_port_operations.
 	</para>
 
@@ -154,8 +148,8 @@ unsigned int (*mode_filter) (struct ata_port *, struct ata_device *, unsigned in
 
 	<sect2><title>Taskfile read/write</title>
 	<programlisting>
-void (*tf_load) (struct ata_port *ap, struct ata_taskfile *tf);
-void (*tf_read) (struct ata_port *ap, struct ata_taskfile *tf);
+void (*sff_tf_load) (struct ata_port *ap, struct ata_taskfile *tf);
+void (*sff_tf_read) (struct ata_port *ap, struct ata_taskfile *tf);
 	</programlisting>
 
 	<para>
@@ -164,36 +158,35 @@ void (*tf_read) (struct ata_port *ap, struct ata_taskfile *tf);
 	hardware registers / DMA buffers, to obtain the current set of
 	taskfile register values.
 	Most drivers for taskfile-based hardware (PIO or MMIO) use
-	ata_tf_load() and ata_tf_read() for these hooks.
+	ata_sff_tf_load() and ata_sff_tf_read() for these hooks.
 	</para>
 
 	</sect2>
 
 	<sect2><title>PIO data read/write</title>
 	<programlisting>
-void (*data_xfer) (struct ata_device *, unsigned char *, unsigned int, int);
+void (*sff_data_xfer) (struct ata_device *, unsigned char *, unsigned int, int);
 	</programlisting>
 
 	<para>
 All bmdma-style drivers must implement this hook.  This is the low-level
 operation that actually copies the data bytes during a PIO data
 transfer.
-Typically the driver
-will choose one of ata_pio_data_xfer_noirq(), ata_pio_data_xfer(), or
-ata_mmio_data_xfer().
+Typically the driver will choose one of ata_sff_data_xfer_noirq(),
+ata_sff_data_xfer(), or ata_sff_data_xfer32().
 	</para>
 
 	</sect2>
 
 	<sect2><title>ATA command execute</title>
 	<programlisting>
-void (*exec_command)(struct ata_port *ap, struct ata_taskfile *tf);
+void (*sff_exec_command)(struct ata_port *ap, struct ata_taskfile *tf);
 	</programlisting>
 
 	<para>
 	causes an ATA command, previously loaded with
 	->tf_load(), to be initiated in hardware.
-	Most drivers for taskfile-based hardware use ata_exec_command()
+	Most drivers for taskfile-based hardware use ata_sff_exec_command()
 	for this hook.
 	</para>
 
@@ -218,8 +211,8 @@ command.
 
 	<sect2><title>Read specific ATA shadow registers</title>
 	<programlisting>
-u8   (*check_status)(struct ata_port *ap);
-u8   (*check_altstatus)(struct ata_port *ap);
+u8   (*sff_check_status)(struct ata_port *ap);
+u8   (*sff_check_altstatus)(struct ata_port *ap);
 	</programlisting>
 
 	<para>
@@ -227,20 +220,26 @@ u8   (*check_altstatus)(struct ata_port *ap);
 	hardware.  On some hardware, reading the Status register has
 	the side effect of clearing the interrupt condition.
 	Most drivers for taskfile-based hardware use
-	ata_check_status() for this hook.
+	ata_sff_check_status() for this hook.
 	</para>
+
+	</sect2>
+
+	<sect2><title>Write specific ATA shadow register</title>
+	<programlisting>
+void (*sff_set_devctl)(struct ata_port *ap, u8 ctl);
+	</programlisting>
+
 	<para>
-	Note that because this is called from ata_device_add(), at
-	least a dummy function that clears device interrupts must be
-	provided for all drivers, even if the controller doesn't
-	actually have a taskfile status register.
+	Write the device control ATA shadow register to the hardware.
+	Most drivers don't need to define this.
 	</para>
 
 	</sect2>
 
 	<sect2><title>Select ATA device on bus</title>
 	<programlisting>
-void (*dev_select)(struct ata_port *ap, unsigned int device);
+void (*sff_dev_select)(struct ata_port *ap, unsigned int device);
 	</programlisting>
 
 	<para>
@@ -251,9 +250,7 @@ void (*dev_select)(struct ata_port *ap, unsigned int device);
 	</para>
 	<para>
 	Most drivers for taskfile-based hardware use
-	ata_std_dev_select() for this hook.  Controllers which do not
-	support second drives on a port (such as SATA contollers) will
-	use ata_noop_dev_select().
+	ata_sff_dev_select() for this hook.
 	</para>
 
 	</sect2>
@@ -441,13 +438,13 @@ void (*irq_clear) (struct ata_port *);
 	to struct ata_host_set.
 	</para>
 	<para>
-	Most legacy IDE drivers use ata_interrupt() for the
+	Most legacy IDE drivers use ata_sff_interrupt() for the
 	irq_handler hook, which scans all ports in the host_set,
 	determines which queued command was active (if any), and calls
-	ata_host_intr(ap,qc).
+	ata_sff_host_intr(ap,qc).
 	</para>
 	<para>
-	Most legacy IDE drivers use ata_bmdma_irq_clear() for the
+	Most legacy IDE drivers use ata_sff_irq_clear() for the
 	irq_clear() hook, which simply clears the interrupt and error
 	flags in the DMA status register.
 	</para>
@@ -490,16 +487,12 @@ void (*host_stop) (struct ata_host_set *host_set);
 	allocates space for a legacy IDE PRD table and returns.
 	</para>
 	<para>
-	->port_stop() is called after ->host_stop().  It's sole function
+	->port_stop() is called after ->host_stop().  Its sole function
 	is to release DMA/memory resources, now that they are no longer
 	actively being used.  Many drivers also free driver-private
 	data from port at this time.
 	</para>
 	<para>
-	Many drivers use ata_port_stop() as this hook, which frees the
-	PRD table.
-	</para>
-	<para>
 	->host_stop() is called after all ->port_stop() calls
 have completed.  The hook must finalize hardware shutdown, release DMA
 and other resources, etc.

Documentation/DocBook/media-entities.tmpl

@@ -17,6 +17,7 @@
 <!ENTITY VIDIOC-DBG-G-REGISTER "<link linkend='vidioc-dbg-g-register'><constant>VIDIOC_DBG_G_REGISTER</constant></link>">
 <!ENTITY VIDIOC-DBG-S-REGISTER "<link linkend='vidioc-dbg-g-register'><constant>VIDIOC_DBG_S_REGISTER</constant></link>">
 <!ENTITY VIDIOC-DQBUF "<link linkend='vidioc-qbuf'><constant>VIDIOC_DQBUF</constant></link>">
+<!ENTITY VIDIOC-DQEVENT "<link linkend='vidioc-dqevent'><constant>VIDIOC_DQEVENT</constant></link>">
 <!ENTITY VIDIOC-ENCODER-CMD "<link linkend='vidioc-encoder-cmd'><constant>VIDIOC_ENCODER_CMD</constant></link>">
 <!ENTITY VIDIOC-ENUMAUDIO "<link linkend='vidioc-enumaudio'><constant>VIDIOC_ENUMAUDIO</constant></link>">
 <!ENTITY VIDIOC-ENUMAUDOUT "<link linkend='vidioc-enumaudioout'><constant>VIDIOC_ENUMAUDOUT</constant></link>">
@@ -60,6 +61,7 @@
 <!ENTITY VIDIOC-REQBUFS "<link linkend='vidioc-reqbufs'><constant>VIDIOC_REQBUFS</constant></link>">
 <!ENTITY VIDIOC-STREAMOFF "<link linkend='vidioc-streamon'><constant>VIDIOC_STREAMOFF</constant></link>">
 <!ENTITY VIDIOC-STREAMON "<link linkend='vidioc-streamon'><constant>VIDIOC_STREAMON</constant></link>">
+<!ENTITY VIDIOC-SUBSCRIBE-EVENT "<link linkend='vidioc-subscribe-event'><constant>VIDIOC_SUBSCRIBE_EVENT</constant></link>">
 <!ENTITY VIDIOC-S-AUDIO "<link linkend='vidioc-g-audio'><constant>VIDIOC_S_AUDIO</constant></link>">
 <!ENTITY VIDIOC-S-AUDOUT "<link linkend='vidioc-g-audioout'><constant>VIDIOC_S_AUDOUT</constant></link>">
 <!ENTITY VIDIOC-S-CROP "<link linkend='vidioc-g-crop'><constant>VIDIOC_S_CROP</constant></link>">
@@ -83,6 +85,7 @@
 <!ENTITY VIDIOC-TRY-ENCODER-CMD "<link linkend='vidioc-encoder-cmd'><constant>VIDIOC_TRY_ENCODER_CMD</constant></link>">
 <!ENTITY VIDIOC-TRY-EXT-CTRLS "<link linkend='vidioc-g-ext-ctrls'><constant>VIDIOC_TRY_EXT_CTRLS</constant></link>">
 <!ENTITY VIDIOC-TRY-FMT "<link linkend='vidioc-g-fmt'><constant>VIDIOC_TRY_FMT</constant></link>">
+<!ENTITY VIDIOC-UNSUBSCRIBE-EVENT "<link linkend='vidioc-subscribe-event'><constant>VIDIOC_UNSUBSCRIBE_EVENT</constant></link>">
 
 <!-- Types -->
 <!ENTITY v4l2-std-id "<link linkend='v4l2-std-id'>v4l2_std_id</link>">
@@ -141,6 +144,9 @@
 <!ENTITY v4l2-enc-idx "struct&nbsp;<link linkend='v4l2-enc-idx'>v4l2_enc_idx</link>">
 <!ENTITY v4l2-enc-idx-entry "struct&nbsp;<link linkend='v4l2-enc-idx-entry'>v4l2_enc_idx_entry</link>">
 <!ENTITY v4l2-encoder-cmd "struct&nbsp;<link linkend='v4l2-encoder-cmd'>v4l2_encoder_cmd</link>">
+<!ENTITY v4l2-event "struct&nbsp;<link linkend='v4l2-event'>v4l2_event</link>">
+<!ENTITY v4l2-event-subscription "struct&nbsp;<link linkend='v4l2-event-subscription'>v4l2_event_subscription</link>">
+<!ENTITY v4l2-event-vsync "struct&nbsp;<link linkend='v4l2-event-vsync'>v4l2_event_vsync</link>">
 <!ENTITY v4l2-ext-control "struct&nbsp;<link linkend='v4l2-ext-control'>v4l2_ext_control</link>">
 <!ENTITY v4l2-ext-controls "struct&nbsp;<link linkend='v4l2-ext-controls'>v4l2_ext_controls</link>">
 <!ENTITY v4l2-fmtdesc "struct&nbsp;<link linkend='v4l2-fmtdesc'>v4l2_fmtdesc</link>">
@@ -200,6 +206,7 @@
 <!ENTITY sub-controls SYSTEM "v4l/controls.xml">
 <!ENTITY sub-dev-capture SYSTEM "v4l/dev-capture.xml">
 <!ENTITY sub-dev-codec SYSTEM "v4l/dev-codec.xml">
+<!ENTITY sub-dev-event SYSTEM "v4l/dev-event.xml">
 <!ENTITY sub-dev-effect SYSTEM "v4l/dev-effect.xml">
 <!ENTITY sub-dev-osd SYSTEM "v4l/dev-osd.xml">
 <!ENTITY sub-dev-output SYSTEM "v4l/dev-output.xml">
@@ -292,6 +299,8 @@
 <!ENTITY sub-v4l2grab-c SYSTEM "v4l/v4l2grab.c.xml">
 <!ENTITY sub-videodev2-h SYSTEM "v4l/videodev2.h.xml">
 <!ENTITY sub-v4l2 SYSTEM "v4l/v4l2.xml">
+<!ENTITY sub-dqevent SYSTEM "v4l/vidioc-dqevent.xml">
+<!ENTITY sub-subscribe-event SYSTEM "v4l/vidioc-subscribe-event.xml">
 <!ENTITY sub-intro SYSTEM "dvb/intro.xml">
 <!ENTITY sub-frontend SYSTEM "dvb/frontend.xml">
 <!ENTITY sub-dvbproperty SYSTEM "dvb/dvbproperty.xml">
@@ -381,3 +390,5 @@
 <!ENTITY reqbufs SYSTEM "v4l/vidioc-reqbufs.xml">
 <!ENTITY s-hw-freq-seek SYSTEM "v4l/vidioc-s-hw-freq-seek.xml">
 <!ENTITY streamon SYSTEM "v4l/vidioc-streamon.xml">
+<!ENTITY dqevent SYSTEM "v4l/vidioc-dqevent.xml">
+<!ENTITY subscribe_event SYSTEM "v4l/vidioc-subscribe-event.xml">

Documentation/DocBook/mtdnand.tmpl

@@ -269,7 +269,7 @@ static void board_hwcontrol(struct mtd_info *mtd, int cmd)
 			information about the device.
 		</para>
 		<programlisting>
-int __init board_init (void)
+static int __init board_init (void)
 {
 	struct nand_chip *this;
 	int err = 0;

Documentation/DocBook/sh.tmpl

@@ -19,13 +19,17 @@
   </authorgroup>
 
   <copyright>
-   <year>2008</year>
+   <year>2008-2010</year>
    <holder>Paul Mundt</holder>
   </copyright>
   <copyright>
-   <year>2008</year>
+   <year>2008-2010</year>
    <holder>Renesas Technology Corp.</holder>
   </copyright>
+  <copyright>
+   <year>2010</year>
+   <holder>Renesas Electronics Corp.</holder>
+  </copyright>
 
   <legalnotice>
    <para>
@@ -77,7 +81,7 @@
   </chapter>
   <chapter id="clk">
     <title>Clock Framework Extensions</title>
-!Iarch/sh/include/asm/clock.h
+!Iinclude/linux/sh_clk.h
   </chapter>
   <chapter id="mach">
     <title>Machine Specific Interfaces</title>

Documentation/DocBook/tracepoint.tmpl

@@ -16,6 +16,15 @@
      </address>
     </affiliation>
    </author>
+   <author>
+    <firstname>William</firstname>
+    <surname>Cohen</surname>
+    <affiliation>
+     <address>
+      <email>wcohen@redhat.com</email>
+     </address>
+    </affiliation>
+   </author>
   </authorgroup>
 
   <legalnotice>
@@ -91,4 +100,8 @@
 !Iinclude/trace/events/signal.h
   </chapter>
 
+  <chapter id="block">
+   <title>Block IO</title>
+!Iinclude/trace/events/block.h
+  </chapter>
 </book>

Documentation/DocBook/v4l/compat.xml

@@ -2332,15 +2332,26 @@ more information.</para>
 	</listitem>
       </orderedlist>
     </section>
-   </section>
+    <section>
+      <title>V4L2 in Linux 2.6.34</title>
+      <orderedlist>
+	<listitem>
+	  <para>Added
+<constant>V4L2_CID_IRIS_ABSOLUTE</constant> and
+<constant>V4L2_CID_IRIS_RELATIVE</constant> controls to the
+	    <link linkend="camera-controls">Camera controls class</link>.
+	  </para>
+	</listitem>
+      </orderedlist>
+    </section>
 
-   <section id="other">
-     <title>Relation of V4L2 to other Linux multimedia APIs</title>
+    <section id="other">
+      <title>Relation of V4L2 to other Linux multimedia APIs</title>
 
-    <section id="xvideo">
-      <title>X Video Extension</title>
+      <section id="xvideo">
+        <title>X Video Extension</title>
 
-      <para>The X Video Extension (abbreviated XVideo or just Xv) is
+        <para>The X Video Extension (abbreviated XVideo or just Xv) is
 an extension of the X Window system, implemented for example by the
 XFree86 project. Its scope is similar to V4L2, an API to video capture
 and output devices for X clients. Xv allows applications to display
@@ -2351,7 +2362,7 @@ capture or output still images in XPixmaps<footnote>
 extension available across many operating systems and
 architectures.</para>
 
-      <para>Because the driver is embedded into the X server Xv has a
+        <para>Because the driver is embedded into the X server Xv has a
 number of advantages over the V4L2 <link linkend="overlay">video
 overlay interface</link>. The driver can easily determine the overlay
 target, &ie; visible graphics memory or off-screen buffers for a
@@ -2360,16 +2371,16 @@ overlay, scaling or color-keying, or the clipping functions of the
 video capture hardware, always in sync with drawing operations or
 windows moving or changing their stacking order.</para>
 
-      <para>To combine the advantages of Xv and V4L a special Xv
+        <para>To combine the advantages of Xv and V4L a special Xv
 driver exists in XFree86 and XOrg, just programming any overlay capable
 Video4Linux device it finds. To enable it
 <filename>/etc/X11/XF86Config</filename> must contain these lines:</para>
-      <para><screen>
+        <para><screen>
 Section "Module"
     Load "v4l"
 EndSection</screen></para>
 
-      <para>As of XFree86 4.2 this driver still supports only V4L
+        <para>As of XFree86 4.2 this driver still supports only V4L
 ioctls, however it should work just fine with all V4L2 devices through
 the V4L2 backward-compatibility layer. Since V4L2 permits multiple
 opens it is possible (if supported by the V4L2 driver) to capture
@@ -2377,83 +2388,84 @@ video while an X client requested video overlay. Restrictions of
 simultaneous capturing and overlay are discussed in <xref
 	  linkend="overlay" /> apply.</para>
 
-      <para>Only marginally related to V4L2, XFree86 extended Xv to
+        <para>Only marginally related to V4L2, XFree86 extended Xv to
 support hardware YUV to RGB conversion and scaling for faster video
 playback, and added an interface to MPEG-2 decoding hardware. This API
 is useful to display images captured with V4L2 devices.</para>
-    </section>
+      </section>
 
-    <section>
-      <title>Digital Video</title>
+      <section>
+        <title>Digital Video</title>
 
-      <para>V4L2 does not support digital terrestrial, cable or
+        <para>V4L2 does not support digital terrestrial, cable or
 satellite broadcast. A separate project aiming at digital receivers
 exists. You can find its homepage at <ulink
 url="http://linuxtv.org">http://linuxtv.org</ulink>. The Linux DVB API
 has no connection to the V4L2 API except that drivers for hybrid
 hardware may support both.</para>
-    </section>
+      </section>
 
-    <section>
-      <title>Audio Interfaces</title>
+      <section>
+        <title>Audio Interfaces</title>
 
-      <para>[to do - OSS/ALSA]</para>
+        <para>[to do - OSS/ALSA]</para>
+      </section>
     </section>
-  </section>
 
-  <section id="experimental">
-    <title>Experimental API Elements</title>
+    <section id="experimental">
+      <title>Experimental API Elements</title>
 
-    <para>The following V4L2 API elements are currently experimental
+      <para>The following V4L2 API elements are currently experimental
 and may change in the future.</para>
 
-    <itemizedlist>
-      <listitem>
-	<para>Video Output Overlay (OSD) Interface, <xref
+      <itemizedlist>
+        <listitem>
+	  <para>Video Output Overlay (OSD) Interface, <xref
 	    linkend="osd" />.</para>
-      </listitem>
+        </listitem>
 	<listitem>
-	<para><constant>V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY</constant>,
+	  <para><constant>V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY</constant>,
 	&v4l2-buf-type;, <xref linkend="v4l2-buf-type" />.</para>
-      </listitem>
-      <listitem>
-	<para><constant>V4L2_CAP_VIDEO_OUTPUT_OVERLAY</constant>,
+        </listitem>
+        <listitem>
+	  <para><constant>V4L2_CAP_VIDEO_OUTPUT_OVERLAY</constant>,
 &VIDIOC-QUERYCAP; ioctl, <xref linkend="device-capabilities" />.</para>
-      </listitem>
-      <listitem>
-	<para>&VIDIOC-ENUM-FRAMESIZES; and
+        </listitem>
+        <listitem>
+	  <para>&VIDIOC-ENUM-FRAMESIZES; and
 &VIDIOC-ENUM-FRAMEINTERVALS; ioctls.</para>
-      </listitem>
-      <listitem>
-	<para>&VIDIOC-G-ENC-INDEX; ioctl.</para>
-      </listitem>
-      <listitem>
-	<para>&VIDIOC-ENCODER-CMD; and &VIDIOC-TRY-ENCODER-CMD;
+        </listitem>
+        <listitem>
+	  <para>&VIDIOC-G-ENC-INDEX; ioctl.</para>
+        </listitem>
+        <listitem>
+	  <para>&VIDIOC-ENCODER-CMD; and &VIDIOC-TRY-ENCODER-CMD;
 ioctls.</para>
-      </listitem>
-      <listitem>
-	<para>&VIDIOC-DBG-G-REGISTER; and &VIDIOC-DBG-S-REGISTER;
+        </listitem>
+        <listitem>
+	  <para>&VIDIOC-DBG-G-REGISTER; and &VIDIOC-DBG-S-REGISTER;
 ioctls.</para>
-      </listitem>
-      <listitem>
-	<para>&VIDIOC-DBG-G-CHIP-IDENT; ioctl.</para>
-      </listitem>
-    </itemizedlist>
-  </section>
+        </listitem>
+        <listitem>
+	  <para>&VIDIOC-DBG-G-CHIP-IDENT; ioctl.</para>
+        </listitem>
+      </itemizedlist>
+    </section>
 
-  <section id="obsolete">
-    <title>Obsolete API Elements</title>
+    <section id="obsolete">
+      <title>Obsolete API Elements</title>
 
-    <para>The following V4L2 API elements were superseded by new
+      <para>The following V4L2 API elements were superseded by new
 interfaces and should not be implemented in new drivers.</para>
 
-    <itemizedlist>
-      <listitem>
-	<para><constant>VIDIOC_G_MPEGCOMP</constant> and
+      <itemizedlist>
+        <listitem>
+	  <para><constant>VIDIOC_G_MPEGCOMP</constant> and
 <constant>VIDIOC_S_MPEGCOMP</constant> ioctls. Use Extended Controls,
 <xref linkend="extended-controls" />.</para>
-      </listitem>
-    </itemizedlist>
+        </listitem>
+      </itemizedlist>
+    </section>
   </section>
 
   <!--

Documentation/DocBook/v4l/controls.xml

@@ -266,6 +266,12 @@ minimum value disables backlight compensation.</entry>
 	    <entry>boolean</entry>
 	    <entry>Chroma automatic gain control.</entry>
 	  </row>
+	  <row>
+	    <entry><constant>V4L2_CID_CHROMA_GAIN</constant></entry>
+	    <entry>integer</entry>
+	    <entry>Adjusts the Chroma gain control (for use when chroma AGC
+	    is disabled).</entry>
+	  </row>
 	  <row>
 	    <entry><constant>V4L2_CID_COLOR_KILLER</constant></entry>
 	    <entry>boolean</entry>
@@ -277,8 +283,15 @@ minimum value disables backlight compensation.</entry>
 	    <entry>Selects a color effect. Possible values for
 <constant>enum v4l2_colorfx</constant> are:
 <constant>V4L2_COLORFX_NONE</constant> (0),
-<constant>V4L2_COLORFX_BW</constant> (1) and
-<constant>V4L2_COLORFX_SEPIA</constant> (2).</entry>
+<constant>V4L2_COLORFX_BW</constant> (1),
+<constant>V4L2_COLORFX_SEPIA</constant> (2),
+<constant>V4L2_COLORFX_NEGATIVE</constant> (3),
+<constant>V4L2_COLORFX_EMBOSS</constant> (4),
+<constant>V4L2_COLORFX_SKETCH</constant> (5),
+<constant>V4L2_COLORFX_SKY_BLUE</constant> (6),
+<constant>V4L2_COLORFX_GRASS_GREEN</constant> (7),
+<constant>V4L2_COLORFX_SKIN_WHITEN</constant> (8) and
+<constant>V4L2_COLORFX_VIVID</constant> (9).</entry>
 	  </row>
 	  <row>
 	    <entry><constant>V4L2_CID_ROTATE</constant></entry>
@@ -1824,6 +1837,25 @@ wide-angle direction. The zoom speed unit is driver-specific.</entry>
 	  </row>
 	  <row><entry></entry></row>
 
+	  <row>
+	    <entry spanname="id"><constant>V4L2_CID_IRIS_ABSOLUTE</constant>&nbsp;</entry>
+	    <entry>integer</entry>
+	  </row><row><entry spanname="descr">This control sets the
+camera's aperture to the specified value. The unit is undefined.
+Larger values open the iris wider, smaller values close it.</entry>
+	  </row>
+	  <row><entry></entry></row>
+
+	  <row>
+	    <entry spanname="id"><constant>V4L2_CID_IRIS_RELATIVE</constant>&nbsp;</entry>
+	    <entry>integer</entry>
+	  </row><row><entry spanname="descr">This control modifies the
+camera's aperture by the specified amount. The unit is undefined.
+Positive values open the iris one step further, negative values close
+it one step further. This is a write-only control.</entry>
+	  </row>
+	  <row><entry></entry></row>
+
 	  <row>
 	    <entry spanname="id"><constant>V4L2_CID_PRIVACY</constant>&nbsp;</entry>
 	    <entry>boolean</entry>

Documentation/DocBook/v4l/dev-event.xml

@@ -0,0 +1,31 @@
+  <title>Event Interface</title>
+
+  <para>The V4L2 event interface provides means for user to get
+  immediately notified on certain conditions taking place on a device.
+  This might include start of frame or loss of signal events, for
+  example.
+  </para>
+
+  <para>To receive events, the events the user is interested in first must
+  be subscribed using the &VIDIOC-SUBSCRIBE-EVENT; ioctl. Once an event is
+  subscribed, the events of subscribed types are dequeueable using the
+  &VIDIOC-DQEVENT; ioctl. Events may be unsubscribed using
+  VIDIOC_UNSUBSCRIBE_EVENT ioctl. The special event type V4L2_EVENT_ALL may
+  be used to unsubscribe all the events the driver supports.</para>
+
+  <para>The event subscriptions and event queues are specific to file
+  handles. Subscribing an event on one file handle does not affect
+  other file handles.
+  </para>
+
+  <para>The information on dequeueable events is obtained by using select or
+  poll system calls on video devices. The V4L2 events use POLLPRI events on
+  poll system call and exceptions on select system call.  </para>
+
+  <!--
+Local Variables:
+mode: sgml
+sgml-parent-document: "v4l2.sgml"
+indent-tabs-mode: nil
+End:
+  -->

Documentation/DocBook/v4l/io.xml

@@ -701,6 +701,16 @@ buffer cannot be on both queues at the same time, the
 They can be both cleared however, then the buffer is in "dequeued"
 state, in the application domain to say so.</entry>
 	  </row>
+	  <row>
+	    <entry><constant>V4L2_BUF_FLAG_ERROR</constant></entry>
+	    <entry>0x0040</entry>
+	    <entry>When this flag is set, the buffer has been dequeued
+	    successfully, although the data might have been corrupted.
+	    This is recoverable, streaming may continue as normal and
+	    the buffer may be reused normally.
+	    Drivers set this flag when the <constant>VIDIOC_DQBUF</constant>
+	    ioctl is called.</entry>
+	  </row>
 	  <row>
 	    <entry><constant>V4L2_BUF_FLAG_KEYFRAME</constant></entry>
 	    <entry>0x0008</entry>
@@ -918,8 +928,8 @@ order</emphasis>.</para>
 
     <para>When the driver provides or accepts images field by field
 rather than interleaved, it is also important applications understand
-how the fields combine to frames. We distinguish between top and
-bottom fields, the <emphasis>spatial order</emphasis>: The first line
+how the fields combine to frames. We distinguish between top (aka odd) and
+bottom (aka even) fields, the <emphasis>spatial order</emphasis>: The first line
 of the top field is the first line of an interlaced frame, the first
 line of the bottom field is the second line of that frame.</para>
 
@@ -972,12 +982,12 @@ between <constant>V4L2_FIELD_TOP</constant> and
 	  <row>
 	    <entry><constant>V4L2_FIELD_TOP</constant></entry>
 	    <entry>2</entry>
-	    <entry>Images consist of the top field only.</entry>
+	    <entry>Images consist of the top (aka odd) field only.</entry>
 	  </row>
 	  <row>
 	    <entry><constant>V4L2_FIELD_BOTTOM</constant></entry>
 	    <entry>3</entry>
-	    <entry>Images consist of the bottom field only.
+	    <entry>Images consist of the bottom (aka even) field only.
 Applications may wish to prevent a device from capturing interlaced
 images because they will have "comb" or "feathering" artefacts around
 moving objects.</entry>

Documentation/DocBook/v4l/pixfmt.xml

@@ -792,6 +792,18 @@ http://www.thedirks.org/winnov/</ulink></para></entry>
 	    <entry>'YYUV'</entry>
 	    <entry>unknown</entry>
 	  </row>
+	  <row id="V4L2-PIX-FMT-Y4">
+	    <entry><constant>V4L2_PIX_FMT_Y4</constant></entry>
+	    <entry>'Y04 '</entry>
+	    <entry>Old 4-bit greyscale format. Only the least significant 4 bits of each byte are used,
+the other bits are set to 0.</entry>
+	  </row>
+	  <row id="V4L2-PIX-FMT-Y6">
+	    <entry><constant>V4L2_PIX_FMT_Y6</constant></entry>
+	    <entry>'Y06 '</entry>
+	    <entry>Old 6-bit greyscale format. Only the least significant 6 bits of each byte are used,
+the other bits are set to 0.</entry>
+	  </row>
 	</tbody>
       </tgroup>
     </table>

Documentation/DocBook/v4l/v4l2.xml

@@ -401,6 +401,7 @@ and discussions on the V4L mailing list.</revremark>
     <section id="ttx"> &sub-dev-teletext; </section>
     <section id="radio"> &sub-dev-radio; </section>
     <section id="rds"> &sub-dev-rds; </section>
+    <section id="event"> &sub-dev-event; </section>
   </chapter>
 
   <chapter id="driver">
@@ -426,6 +427,7 @@ and discussions on the V4L mailing list.</revremark>
     &sub-cropcap;
     &sub-dbg-g-chip-ident;
     &sub-dbg-g-register;
+    &sub-dqevent;
     &sub-encoder-cmd;
     &sub-enumaudio;
     &sub-enumaudioout;
@@ -467,6 +469,7 @@ and discussions on the V4L mailing list.</revremark>
     &sub-reqbufs;
     &sub-s-hw-freq-seek;
     &sub-streamon;
+    &sub-subscribe-event;
     <!-- End of ioctls. -->
     &sub-mmap;
     &sub-munmap;

Documentation/DocBook/v4l/videodev2.h.xml

@@ -1018,6 +1018,13 @@ enum <link linkend="v4l2-colorfx">v4l2_colorfx</link> {
         V4L2_COLORFX_NONE       = 0,
         V4L2_COLORFX_BW         = 1,
         V4L2_COLORFX_SEPIA      = 2,
+        V4L2_COLORFX_NEGATIVE   = 3,
+        V4L2_COLORFX_EMBOSS     = 4,
+        V4L2_COLORFX_SKETCH     = 5,
+        V4L2_COLORFX_SKY_BLUE   = 6,
+        V4L2_COLORFX_GRASS_GREEN = 7,
+        V4L2_COLORFX_SKIN_WHITEN = 8,
+        V4L2_COLORFX_VIVID      = 9.
 };
 #define V4L2_CID_AUTOBRIGHTNESS                 (V4L2_CID_BASE+32)
 #define V4L2_CID_BAND_STOP_FILTER               (V4L2_CID_BASE+33)
@@ -1271,6 +1278,9 @@ enum  <link linkend="v4l2-exposure-auto-type">v4l2_exposure_auto_type</link> {
 
 #define V4L2_CID_PRIVACY                        (V4L2_CID_CAMERA_CLASS_BASE+16)
 
+#define V4L2_CID_IRIS_ABSOLUTE                  (V4L2_CID_CAMERA_CLASS_BASE+17)
+#define V4L2_CID_IRIS_RELATIVE                  (V4L2_CID_CAMERA_CLASS_BASE+18)
+
 /* FM Modulator class control IDs */
 #define V4L2_CID_FM_TX_CLASS_BASE               (V4L2_CTRL_CLASS_FM_TX | 0x900)
 #define V4L2_CID_FM_TX_CLASS                    (V4L2_CTRL_CLASS_FM_TX | 1)

Documentation/DocBook/v4l/vidioc-dqevent.xml

@@ -0,0 +1,131 @@
+<refentry id="vidioc-dqevent">
+  <refmeta>
+    <refentrytitle>ioctl VIDIOC_DQEVENT</refentrytitle>
+    &manvol;
+  </refmeta>
+
+  <refnamediv>
+    <refname>VIDIOC_DQEVENT</refname>
+    <refpurpose>Dequeue event</refpurpose>
+  </refnamediv>
+
+  <refsynopsisdiv>
+    <funcsynopsis>
+      <funcprototype>
+	<funcdef>int <function>ioctl</function></funcdef>
+	<paramdef>int <parameter>fd</parameter></paramdef>
+	<paramdef>int <parameter>request</parameter></paramdef>
+	<paramdef>struct v4l2_event
+*<parameter>argp</parameter></paramdef>
+      </funcprototype>
+    </funcsynopsis>
+  </refsynopsisdiv>
+
+  <refsect1>
+    <title>Arguments</title>
+
+    <variablelist>
+      <varlistentry>
+	<term><parameter>fd</parameter></term>
+	<listitem>
+	  <para>&fd;</para>
+	</listitem>
+      </varlistentry>
+      <varlistentry>
+	<term><parameter>request</parameter></term>
+	<listitem>
+	  <para>VIDIOC_DQEVENT</para>
+	</listitem>
+      </varlistentry>
+      <varlistentry>
+	<term><parameter>argp</parameter></term>
+	<listitem>
+	  <para></para>
+	</listitem>
+      </varlistentry>
+    </variablelist>
+  </refsect1>
+
+  <refsect1>
+    <title>Description</title>
+
+    <para>Dequeue an event from a video device. No input is required
+    for this ioctl. All the fields of the &v4l2-event; structure are
+    filled by the driver. The file handle will also receive exceptions
+    which the application may get by e.g. using the select system
+    call.</para>
+
+    <table frame="none" pgwide="1" id="v4l2-event">
+      <title>struct <structname>v4l2_event</structname></title>
+      <tgroup cols="4">
+	&cs-str;
+	<tbody valign="top">
+	  <row>
+	    <entry>__u32</entry>
+	    <entry><structfield>type</structfield></entry>
+            <entry></entry>
+	    <entry>Type of the event.</entry>
+	  </row>
+	  <row>
+	    <entry>union</entry>
+	    <entry><structfield>u</structfield></entry>
+            <entry></entry>
+	    <entry></entry>
+	  </row>
+	  <row>
+	    <entry></entry>
+	    <entry>&v4l2-event-vsync;</entry>
+            <entry><structfield>vsync</structfield></entry>
+	    <entry>Event data for event V4L2_EVENT_VSYNC.
+            </entry>
+	  </row>
+	  <row>
+	    <entry></entry>
+	    <entry>__u8</entry>
+            <entry><structfield>data</structfield>[64]</entry>
+	    <entry>Event data. Defined by the event type. The union
+            should be used to define easily accessible type for
+            events.</entry>
+	  </row>
+	  <row>
+	    <entry>__u32</entry>
+	    <entry><structfield>pending</structfield></entry>
+            <entry></entry>
+	    <entry>Number of pending events excluding this one.</entry>
+	  </row>
+	  <row>
+	    <entry>__u32</entry>
+	    <entry><structfield>sequence</structfield></entry>
+            <entry></entry>
+	    <entry>Event sequence number. The sequence number is
+	    incremented for every subscribed event that takes place.
+	    If sequence numbers are not contiguous it means that
+	    events have been lost.
+	    </entry>
+	  </row>
+	  <row>
+	    <entry>struct timespec</entry>
+	    <entry><structfield>timestamp</structfield></entry>
+            <entry></entry>
+	    <entry>Event timestamp.</entry>
+	  </row>
+	  <row>
+	    <entry>__u32</entry>
+	    <entry><structfield>reserved</structfield>[9]</entry>
+            <entry></entry>
+	    <entry>Reserved for future extensions. Drivers must set
+	    the array to zero.</entry>
+	  </row>
+	</tbody>
+      </tgroup>
+    </table>
+
+  </refsect1>
+</refentry>
+<!--
+Local Variables:
+mode: sgml
+sgml-parent-document: "v4l2.sgml"
+indent-tabs-mode: nil
+End:
+-->

Documentation/DocBook/v4l/vidioc-enuminput.xml

@@ -283,7 +283,7 @@ input/output interface to linux-media@vger.kernel.org on 19 Oct 2009.
 	    <entry>This input supports setting DV presets by using VIDIOC_S_DV_PRESET.</entry>
 	  </row>
 	  <row>
-	    <entry><constant>V4L2_OUT_CAP_CUSTOM_TIMINGS</constant></entry>
+	    <entry><constant>V4L2_IN_CAP_CUSTOM_TIMINGS</constant></entry>
 	    <entry>0x00000002</entry>
 	    <entry>This input supports setting custom video timings by using VIDIOC_S_DV_TIMINGS.</entry>
 	  </row>

Documentation/DocBook/v4l/vidioc-qbuf.xml

@@ -111,7 +111,11 @@ from the driver's outgoing queue. They just set the
 and <structfield>reserved</structfield>
 fields of a &v4l2-buffer; as above, when <constant>VIDIOC_DQBUF</constant>
 is called with a pointer to this structure the driver fills the
-remaining fields or returns an error code.</para>
+remaining fields or returns an error code. The driver may also set
+<constant>V4L2_BUF_FLAG_ERROR</constant> in the <structfield>flags</structfield>
+field. It indicates a non-critical (recoverable) streaming error. In such case
+the application may continue as normal, but should be aware that data in the
+dequeued buffer might be corrupted.</para>
 
     <para>By default <constant>VIDIOC_DQBUF</constant> blocks when no
 buffer is in the outgoing queue. When the
@@ -158,7 +162,13 @@ enqueue a user pointer buffer.</para>
 	  <para><constant>VIDIOC_DQBUF</constant> failed due to an
 internal error. Can also indicate temporary problems like signal
 loss. Note the driver might dequeue an (empty) buffer despite
-returning an error, or even stop capturing.</para>
+returning an error, or even stop capturing. Reusing such buffer may be unsafe
+though and its details (e.g. <structfield>index</structfield>) may not be
+returned either. It is recommended that drivers indicate recoverable errors
+by setting the <constant>V4L2_BUF_FLAG_ERROR</constant> and returning 0 instead.
+In that case the application should be able to safely reuse the buffer and
+continue streaming.
+	</para>
 	</listitem>
       </varlistentry>
     </variablelist>

Documentation/DocBook/v4l/vidioc-queryctrl.xml

@@ -325,7 +325,7 @@ should be part of the control documentation.</entry>
 	    <entry>n/a</entry>
 	    <entry>This is not a control. When
 <constant>VIDIOC_QUERYCTRL</constant> is called with a control ID
-equal to a control class code (see <xref linkend="ctrl-class" />), the
+equal to a control class code (see <xref linkend="ctrl-class" />) + 1, the
 ioctl returns the name of the control class and this control type.
 Older drivers which do not support this feature return an
 &EINVAL;.</entry>

Documentation/DocBook/v4l/vidioc-reqbufs.xml

@@ -61,7 +61,7 @@ fields of the <structname>v4l2_requestbuffers</structname> structure.
 They set the <structfield>type</structfield> field to the respective
 stream or buffer type, the <structfield>count</structfield> field to
 the desired number of buffers, <structfield>memory</structfield>
-must be set to the requested I/O method and the reserved array
+must be set to the requested I/O method and the <structfield>reserved</structfield> array
 must be zeroed. When the ioctl
 is called with a pointer to this structure the driver will attempt to allocate
 the requested number of buffers and it stores the actual number

Documentation/DocBook/v4l/vidioc-subscribe-event.xml

@@ -0,0 +1,133 @@
+<refentry id="vidioc-subscribe-event">
+  <refmeta>
+    <refentrytitle>ioctl VIDIOC_SUBSCRIBE_EVENT, VIDIOC_UNSUBSCRIBE_EVENT</refentrytitle>
+    &manvol;
+  </refmeta>
+
+  <refnamediv>
+    <refname>VIDIOC_SUBSCRIBE_EVENT, VIDIOC_UNSUBSCRIBE_EVENT</refname>
+    <refpurpose>Subscribe or unsubscribe event</refpurpose>
+  </refnamediv>
+
+  <refsynopsisdiv>
+    <funcsynopsis>
+      <funcprototype>
+	<funcdef>int <function>ioctl</function></funcdef>
+	<paramdef>int <parameter>fd</parameter></paramdef>
+	<paramdef>int <parameter>request</parameter></paramdef>
+	<paramdef>struct v4l2_event_subscription
+*<parameter>argp</parameter></paramdef>
+      </funcprototype>
+    </funcsynopsis>
+  </refsynopsisdiv>
+
+  <refsect1>
+    <title>Arguments</title>
+
+    <variablelist>
+      <varlistentry>
+	<term><parameter>fd</parameter></term>
+	<listitem>
+	  <para>&fd;</para>
+	</listitem>
+      </varlistentry>
+      <varlistentry>
+	<term><parameter>request</parameter></term>
+	<listitem>
+	  <para>VIDIOC_SUBSCRIBE_EVENT, VIDIOC_UNSUBSCRIBE_EVENT</para>
+	</listitem>
+      </varlistentry>
+      <varlistentry>
+	<term><parameter>argp</parameter></term>
+	<listitem>
+	  <para></para>
+	</listitem>
+      </varlistentry>
+    </variablelist>
+  </refsect1>
+
+  <refsect1>
+    <title>Description</title>
+
+    <para>Subscribe or unsubscribe V4L2 event. Subscribed events are
+    dequeued by using the &VIDIOC-DQEVENT; ioctl.</para>
+
+    <table frame="none" pgwide="1" id="v4l2-event-subscription">
+      <title>struct <structname>v4l2_event_subscription</structname></title>
+      <tgroup cols="3">
+	&cs-str;
+	<tbody valign="top">
+	  <row>
+	    <entry>__u32</entry>
+	    <entry><structfield>type</structfield></entry>
+	    <entry>Type of the event.</entry>
+	  </row>
+	  <row>
+	    <entry>__u32</entry>
+	    <entry><structfield>reserved</structfield>[7]</entry>
+	    <entry>Reserved for future extensions. Drivers and applications
+	    must set the array to zero.</entry>
+	  </row>
+	</tbody>
+      </tgroup>
+    </table>
+
+    <table frame="none" pgwide="1" id="event-type">
+      <title>Event Types</title>
+      <tgroup cols="3">
+	&cs-def;
+	<tbody valign="top">
+	  <row>
+	    <entry><constant>V4L2_EVENT_ALL</constant></entry>
+	    <entry>0</entry>
+	    <entry>All events. V4L2_EVENT_ALL is valid only for
+	    VIDIOC_UNSUBSCRIBE_EVENT for unsubscribing all events at once.
+	    </entry>
+	  </row>
+	  <row>
+	    <entry><constant>V4L2_EVENT_VSYNC</constant></entry>
+	    <entry>1</entry>
+	    <entry>This event is triggered on the vertical sync.
+	    This event has &v4l2-event-vsync; associated with it.
+	    </entry>
+	  </row>
+	  <row>
+	    <entry><constant>V4L2_EVENT_EOS</constant></entry>
+	    <entry>2</entry>
+	    <entry>This event is triggered when the end of a stream is reached.
+	    This is typically used with MPEG decoders to report to the application
+	    when the last of the MPEG stream has been decoded.
+	    </entry>
+	  </row>
+	  <row>
+	    <entry><constant>V4L2_EVENT_PRIVATE_START</constant></entry>
+	    <entry>0x08000000</entry>
+	    <entry>Base event number for driver-private events.</entry>
+	  </row>
+	</tbody>
+      </tgroup>
+    </table>
+
+    <table frame="none" pgwide="1" id="v4l2-event-vsync">
+      <title>struct <structname>v4l2_event_vsync</structname></title>
+      <tgroup cols="3">
+	&cs-str;
+	<tbody valign="top">
+	  <row>
+	    <entry>__u8</entry>
+	    <entry><structfield>field</structfield></entry>
+	    <entry>The upcoming field. See &v4l2-field;.</entry>
+	  </row>
+	</tbody>
+      </tgroup>
+    </table>
+
+  </refsect1>
+</refentry>
+<!--
+Local Variables:
+mode: sgml
+sgml-parent-document: "v4l2.sgml"
+indent-tabs-mode: nil
+End:
+-->

Documentation/DocBook/writing-an-alsa-driver.tmpl

@@ -5518,34 +5518,41 @@ struct _snd_pcm_runtime {
 ]]>
         </programlisting>
       </informalexample>
+
+      For the raw data, <structfield>size</structfield> field must be
+      set properly.  This specifies the maximum size of the proc file access.
     </para>
 
     <para>
-      The callback is much more complicated than the text-file
-      version. You need to use a low-level I/O functions such as
+      The read/write callbacks of raw mode are more direct than the text mode.
+      You need to use a low-level I/O functions such as
       <function>copy_from/to_user()</function> to transfer the
       data.
 
       <informalexample>
         <programlisting>
 <![CDATA[
-  static long my_file_io_read(struct snd_info_entry *entry,
+  static ssize_t my_file_io_read(struct snd_info_entry *entry,
                               void *file_private_data,
                               struct file *file,
                               char *buf,
-                              unsigned long count,
-                              unsigned long pos)
+                              size_t count,
+                              loff_t pos)
   {
-          long size = count;
-          if (pos + size > local_max_size)
-                  size = local_max_size - pos;
-          if (copy_to_user(buf, local_data + pos, size))
+          if (copy_to_user(buf, local_data + pos, count))
                   return -EFAULT;
-          return size;
+          return count;
   }
 ]]>
         </programlisting>
       </informalexample>
+
+      If the size of the info entry has been set up properly,
+      <structfield>count</structfield> and <structfield>pos</structfield> are
+      guaranteed to fit within 0 and the given size.
+      You don't have to check the range in the callbacks unless any
+      other condition is required.
+
     </para>
 
   </chapter>

Documentation/DocBook/writing_usb_driver.tmpl

@@ -342,7 +342,7 @@ static inline void skel_delete (struct usb_skel *dev)
 {
     kfree (dev->bulk_in_buffer);
     if (dev->bulk_out_buffer != NULL)
-        usb_buffer_free (dev->udev, dev->bulk_out_size,
+        usb_free_coherent (dev->udev, dev->bulk_out_size,
             dev->bulk_out_buffer,
             dev->write_urb->transfer_dma);
     usb_free_urb (dev->write_urb);

Documentation/HOWTO

@@ -234,7 +234,7 @@ process is as follows:
     Linus, usually the patches that have already been included in the
     -next kernel for a few weeks.  The preferred way to submit big changes
     is using git (the kernel's source management tool, more information
-    can be found at http://git.or.cz/) but plain patches are also just
+    can be found at http://git-scm.com/) but plain patches are also just
     fine.
   - After two weeks a -rc1 kernel is released it is now possible to push
     only patches that do not include new features that could affect the

Documentation/PCI/PCI-DMA-mapping.txt

@@ -1,758 +0,0 @@
-		     Dynamic DMA mapping Guide
-		     =========================
-
-		 David S. Miller <davem@redhat.com>
-		 Richard Henderson <rth@cygnus.com>
-		  Jakub Jelinek <jakub@redhat.com>
-
-This is a guide to device driver writers on how to use the DMA API
-with example pseudo-code.  For a concise description of the API, see
-DMA-API.txt.
-
-Most of the 64bit platforms have special hardware that translates bus
-addresses (DMA addresses) into physical addresses.  This is similar to
-how page tables and/or a TLB translates virtual addresses to physical
-addresses on a CPU.  This is needed so that e.g. PCI devices can
-access with a Single Address Cycle (32bit DMA address) any page in the
-64bit physical address space.  Previously in Linux those 64bit
-platforms had to set artificial limits on the maximum RAM size in the
-system, so that the virt_to_bus() static scheme works (the DMA address
-translation tables were simply filled on bootup to map each bus
-address to the physical page __pa(bus_to_virt())).
-
-So that Linux can use the dynamic DMA mapping, it needs some help from the
-drivers, namely it has to take into account that DMA addresses should be
-mapped only for the time they are actually used and unmapped after the DMA
-transfer.
-
-The following API will work of course even on platforms where no such
-hardware exists.
-
-Note that the DMA API works with any bus independent of the underlying
-microprocessor architecture. You should use the DMA API rather than
-the bus specific DMA API (e.g. pci_dma_*).
-
-First of all, you should make sure
-
-#include <linux/dma-mapping.h>
-
-is in your driver. This file will obtain for you the definition of the
-dma_addr_t (which can hold any valid DMA address for the platform)
-type which should be used everywhere you hold a DMA (bus) address
-returned from the DMA mapping functions.
-
-			 What memory is DMA'able?
-
-The first piece of information you must know is what kernel memory can
-be used with the DMA mapping facilities.  There has been an unwritten
-set of rules regarding this, and this text is an attempt to finally
-write them down.
-
-If you acquired your memory via the page allocator
-(i.e. __get_free_page*()) or the generic memory allocators
-(i.e. kmalloc() or kmem_cache_alloc()) then you may DMA to/from
-that memory using the addresses returned from those routines.
-
-This means specifically that you may _not_ use the memory/addresses
-returned from vmalloc() for DMA.  It is possible to DMA to the
-_underlying_ memory mapped into a vmalloc() area, but this requires
-walking page tables to get the physical addresses, and then
-translating each of those pages back to a kernel address using
-something like __va().  [ EDIT: Update this when we integrate
-Gerd Knorr's generic code which does this. ]
-
-This rule also means that you may use neither kernel image addresses
-(items in data/text/bss segments), nor module image addresses, nor
-stack addresses for DMA.  These could all be mapped somewhere entirely
-different than the rest of physical memory.  Even if those classes of
-memory could physically work with DMA, you'd need to ensure the I/O
-buffers were cacheline-aligned.  Without that, you'd see cacheline
-sharing problems (data corruption) on CPUs with DMA-incoherent caches.
-(The CPU could write to one word, DMA would write to a different one
-in the same cache line, and one of them could be overwritten.)
-
-Also, this means that you cannot take the return of a kmap()
-call and DMA to/from that.  This is similar to vmalloc().
-
-What about block I/O and networking buffers?  The block I/O and
-networking subsystems make sure that the buffers they use are valid
-for you to DMA from/to.
-
-			DMA addressing limitations
-
-Does your device have any DMA addressing limitations?  For example, is
-your device only capable of driving the low order 24-bits of address?
-If so, you need to inform the kernel of this fact.
-
-By default, the kernel assumes that your device can address the full
-32-bits.  For a 64-bit capable device, this needs to be increased.
-And for a device with limitations, as discussed in the previous
-paragraph, it needs to be decreased.
-
-Special note about PCI: PCI-X specification requires PCI-X devices to
-support 64-bit addressing (DAC) for all transactions.  And at least
-one platform (SGI SN2) requires 64-bit consistent allocations to
-operate correctly when the IO bus is in PCI-X mode.
-
-For correct operation, you must interrogate the kernel in your device
-probe routine to see if the DMA controller on the machine can properly
-support the DMA addressing limitation your device has.  It is good
-style to do this even if your device holds the default setting,
-because this shows that you did think about these issues wrt. your
-device.
-
-The query is performed via a call to dma_set_mask():
-
-	int dma_set_mask(struct device *dev, u64 mask);
-
-The query for consistent allocations is performed via a call to
-dma_set_coherent_mask():
-
-	int dma_set_coherent_mask(struct device *dev, u64 mask);
-
-Here, dev is a pointer to the device struct of your device, and mask
-is a bit mask describing which bits of an address your device
-supports.  It returns zero if your card can perform DMA properly on
-the machine given the address mask you provided.  In general, the
-device struct of your device is embedded in the bus specific device
-struct of your device.  For example, a pointer to the device struct of
-your PCI device is pdev->dev (pdev is a pointer to the PCI device
-struct of your device).
-
-If it returns non-zero, your device cannot perform DMA properly on
-this platform, and attempting to do so will result in undefined
-behavior.  You must either use a different mask, or not use DMA.
-
-This means that in the failure case, you have three options:
-
-1) Use another DMA mask, if possible (see below).
-2) Use some non-DMA mode for data transfer, if possible.
-3) Ignore this device and do not initialize it.
-
-It is recommended that your driver print a kernel KERN_WARNING message
-when you end up performing either #2 or #3.  In this manner, if a user
-of your driver reports that performance is bad or that the device is not
-even detected, you can ask them for the kernel messages to find out
-exactly why.
-
-The standard 32-bit addressing device would do something like this:
-
-	if (dma_set_mask(dev, DMA_BIT_MASK(32))) {
-		printk(KERN_WARNING
-		       "mydev: No suitable DMA available.\n");
-		goto ignore_this_device;
-	}
-
-Another common scenario is a 64-bit capable device.  The approach here
-is to try for 64-bit addressing, but back down to a 32-bit mask that
-should not fail.  The kernel may fail the 64-bit mask not because the
-platform is not capable of 64-bit addressing.  Rather, it may fail in
-this case simply because 32-bit addressing is done more efficiently
-than 64-bit addressing.  For example, Sparc64 PCI SAC addressing is
-more efficient than DAC addressing.
-
-Here is how you would handle a 64-bit capable device which can drive
-all 64-bits when accessing streaming DMA:
-
-	int using_dac;
-
-	if (!dma_set_mask(dev, DMA_BIT_MASK(64))) {
-		using_dac = 1;
-	} else if (!dma_set_mask(dev, DMA_BIT_MASK(32))) {
-		using_dac = 0;
-	} else {
-		printk(KERN_WARNING
-		       "mydev: No suitable DMA available.\n");
-		goto ignore_this_device;
-	}
-
-If a card is capable of using 64-bit consistent allocations as well,
-the case would look like this:
-
-	int using_dac, consistent_using_dac;
-
-	if (!dma_set_mask(dev, DMA_BIT_MASK(64))) {
-		using_dac = 1;
-	   	consistent_using_dac = 1;
-		dma_set_coherent_mask(dev, DMA_BIT_MASK(64));
-	} else if (!dma_set_mask(dev, DMA_BIT_MASK(32))) {
-		using_dac = 0;
-		consistent_using_dac = 0;
-		dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
-	} else {
-		printk(KERN_WARNING
-		       "mydev: No suitable DMA available.\n");
-		goto ignore_this_device;
-	}
-
-dma_set_coherent_mask() will always be able to set the same or a
-smaller mask as dma_set_mask(). However for the rare case that a
-device driver only uses consistent allocations, one would have to
-check the return value from dma_set_coherent_mask().
-
-Finally, if your device can only drive the low 24-bits of
-address you might do something like:
-
-	if (dma_set_mask(dev, DMA_BIT_MASK(24))) {
-		printk(KERN_WARNING
-		       "mydev: 24-bit DMA addressing not available.\n");
-		goto ignore_this_device;
-	}
-
-When dma_set_mask() is successful, and returns zero, the kernel saves
-away this mask you have provided.  The kernel will use this
-information later when you make DMA mappings.
-
-There is a case which we are aware of at this time, which is worth
-mentioning in this documentation.  If your device supports multiple
-functions (for example a sound card provides playback and record
-functions) and the various different functions have _different_
-DMA addressing limitations, you may wish to probe each mask and
-only provide the functionality which the machine can handle.  It
-is important that the last call to dma_set_mask() be for the
-most specific mask.
-
-Here is pseudo-code showing how this might be done:
-
-	#define PLAYBACK_ADDRESS_BITS	DMA_BIT_MASK(32)
-	#define RECORD_ADDRESS_BITS	DMA_BIT_MASK(24)
-
-	struct my_sound_card *card;
-	struct device *dev;
-
-	...
-	if (!dma_set_mask(dev, PLAYBACK_ADDRESS_BITS)) {
-		card->playback_enabled = 1;
-	} else {
-		card->playback_enabled = 0;
-		printk(KERN_WARNING "%s: Playback disabled due to DMA limitations.\n",
-		       card->name);
-	}
-	if (!dma_set_mask(dev, RECORD_ADDRESS_BITS)) {
-		card->record_enabled = 1;
-	} else {
-		card->record_enabled = 0;
-		printk(KERN_WARNING "%s: Record disabled due to DMA limitations.\n",
-		       card->name);
-	}
-
-A sound card was used as an example here because this genre of PCI
-devices seems to be littered with ISA chips given a PCI front end,
-and thus retaining the 16MB DMA addressing limitations of ISA.
-
-			Types of DMA mappings
-
-There are two types of DMA mappings:
-
-- Consistent DMA mappings which are usually mapped at driver
-  initialization, unmapped at the end and for which the hardware should
-  guarantee that the device and the CPU can access the data
-  in parallel and will see updates made by each other without any
-  explicit software flushing.
-
-  Think of "consistent" as "synchronous" or "coherent".
-
-  The current default is to return consistent memory in the low 32
-  bits of the bus space.  However, for future compatibility you should
-  set the consistent mask even if this default is fine for your
-  driver.
-
-  Good examples of what to use consistent mappings for are:
-
-	- Network card DMA ring descriptors.
-	- SCSI adapter mailbox command data structures.
-	- Device firmware microcode executed out of
-	  main memory.
-
-  The invariant these examples all require is that any CPU store
-  to memory is immediately visible to the device, and vice
-  versa.  Consistent mappings guarantee this.
-
-  IMPORTANT: Consistent DMA memory does not preclude the usage of
-             proper memory barriers.  The CPU may reorder stores to
-	     consistent memory just as it may normal memory.  Example:
-	     if it is important for the device to see the first word
-	     of a descriptor updated before the second, you must do
-	     something like:
-
-		desc->word0 = address;
-		wmb();
-		desc->word1 = DESC_VALID;
-
-             in order to get correct behavior on all platforms.
-
-	     Also, on some platforms your driver may need to flush CPU write
-	     buffers in much the same way as it needs to flush write buffers
-	     found in PCI bridges (such as by reading a register's value
-	     after writing it).
-
-- Streaming DMA mappings which are usually mapped for one DMA
-  transfer, unmapped right after it (unless you use dma_sync_* below)
-  and for which hardware can optimize for sequential accesses.
-
-  This of "streaming" as "asynchronous" or "outside the coherency
-  domain".
-
-  Good examples of what to use streaming mappings for are:
-
-	- Networking buffers transmitted/received by a device.
-	- Filesystem buffers written/read by a SCSI device.
-
-  The interfaces for using this type of mapping were designed in
-  such a way that an implementation can make whatever performance
-  optimizations the hardware allows.  To this end, when using
-  such mappings you must be explicit about what you want to happen.
-
-Neither type of DMA mapping has alignment restrictions that come from
-the underlying bus, although some devices may have such restrictions.
-Also, systems with caches that aren't DMA-coherent will work better
-when the underlying buffers don't share cache lines with other data.
-
-
-		 Using Consistent DMA mappings.
-
-To allocate and map large (PAGE_SIZE or so) consistent DMA regions,
-you should do:
-
-	dma_addr_t dma_handle;
-
-	cpu_addr = dma_alloc_coherent(dev, size, &dma_handle, gfp);
-
-where device is a struct device *. This may be called in interrupt
-context with the GFP_ATOMIC flag.
-
-Size is the length of the region you want to allocate, in bytes.
-
-This routine will allocate RAM for that region, so it acts similarly to
-__get_free_pages (but takes size instead of a page order).  If your
-driver needs regions sized smaller than a page, you may prefer using
-the dma_pool interface, described below.
-
-The consistent DMA mapping interfaces, for non-NULL dev, will by
-default return a DMA address which is 32-bit addressable.  Even if the
-device indicates (via DMA mask) that it may address the upper 32-bits,
-consistent allocation will only return > 32-bit addresses for DMA if
-the consistent DMA mask has been explicitly changed via
-dma_set_coherent_mask().  This is true of the dma_pool interface as
-well.
-
-dma_alloc_coherent returns two values: the virtual address which you
-can use to access it from the CPU and dma_handle which you pass to the
-card.
-
-The cpu return address and the DMA bus master address are both
-guaranteed to be aligned to the smallest PAGE_SIZE order which
-is greater than or equal to the requested size.  This invariant
-exists (for example) to guarantee that if you allocate a chunk
-which is smaller than or equal to 64 kilobytes, the extent of the
-buffer you receive will not cross a 64K boundary.
-
-To unmap and free such a DMA region, you call:
-
-	dma_free_coherent(dev, size, cpu_addr, dma_handle);
-
-where dev, size are the same as in the above call and cpu_addr and
-dma_handle are the values dma_alloc_coherent returned to you.
-This function may not be called in interrupt context.
-
-If your driver needs lots of smaller memory regions, you can write
-custom code to subdivide pages returned by dma_alloc_coherent,
-or you can use the dma_pool API to do that.  A dma_pool is like
-a kmem_cache, but it uses dma_alloc_coherent not __get_free_pages.
-Also, it understands common hardware constraints for alignment,
-like queue heads needing to be aligned on N byte boundaries.
-
-Create a dma_pool like this:
-
-	struct dma_pool *pool;
-
-	pool = dma_pool_create(name, dev, size, align, alloc);
-
-The "name" is for diagnostics (like a kmem_cache name); dev and size
-are as above.  The device's hardware alignment requirement for this
-type of data is "align" (which is expressed in bytes, and must be a
-power of two).  If your device has no boundary crossing restrictions,
-pass 0 for alloc; passing 4096 says memory allocated from this pool
-must not cross 4KByte boundaries (but at that time it may be better to
-go for dma_alloc_coherent directly instead).
-
-Allocate memory from a dma pool like this:
-
-	cpu_addr = dma_pool_alloc(pool, flags, &dma_handle);
-
-flags are SLAB_KERNEL if blocking is permitted (not in_interrupt nor
-holding SMP locks), SLAB_ATOMIC otherwise.  Like dma_alloc_coherent,
-this returns two values, cpu_addr and dma_handle.
-
-Free memory that was allocated from a dma_pool like this:
-
-	dma_pool_free(pool, cpu_addr, dma_handle);
-
-where pool is what you passed to dma_pool_alloc, and cpu_addr and
-dma_handle are the values dma_pool_alloc returned. This function
-may be called in interrupt context.
-
-Destroy a dma_pool by calling:
-
-	dma_pool_destroy(pool);
-
-Make sure you've called dma_pool_free for all memory allocated
-from a pool before you destroy the pool. This function may not
-be called in interrupt context.
-
-			DMA Direction
-
-The interfaces described in subsequent portions of this document
-take a DMA direction argument, which is an integer and takes on
-one of the following values:
-
- DMA_BIDIRECTIONAL
- DMA_TO_DEVICE
- DMA_FROM_DEVICE
- DMA_NONE
-
-One should provide the exact DMA direction if you know it.
-
-DMA_TO_DEVICE means "from main memory to the device"
-DMA_FROM_DEVICE means "from the device to main memory"
-It is the direction in which the data moves during the DMA
-transfer.
-
-You are _strongly_ encouraged to specify this as precisely
-as you possibly can.
-
-If you absolutely cannot know the direction of the DMA transfer,
-specify DMA_BIDIRECTIONAL.  It means that the DMA can go in
-either direction.  The platform guarantees that you may legally
-specify this, and that it will work, but this may be at the
-cost of performance for example.
-
-The value DMA_NONE is to be used for debugging.  One can
-hold this in a data structure before you come to know the
-precise direction, and this will help catch cases where your
-direction tracking logic has failed to set things up properly.
-
-Another advantage of specifying this value precisely (outside of
-potential platform-specific optimizations of such) is for debugging.
-Some platforms actually have a write permission boolean which DMA
-mappings can be marked with, much like page protections in the user
-program address space.  Such platforms can and do report errors in the
-kernel logs when the DMA controller hardware detects violation of the
-permission setting.
-
-Only streaming mappings specify a direction, consistent mappings
-implicitly have a direction attribute setting of
-DMA_BIDIRECTIONAL.
-
-The SCSI subsystem tells you the direction to use in the
-'sc_data_direction' member of the SCSI command your driver is
-working on.
-
-For Networking drivers, it's a rather simple affair.  For transmit
-packets, map/unmap them with the DMA_TO_DEVICE direction
-specifier.  For receive packets, just the opposite, map/unmap them
-with the DMA_FROM_DEVICE direction specifier.
-
-		  Using Streaming DMA mappings
-
-The streaming DMA mapping routines can be called from interrupt
-context.  There are two versions of each map/unmap, one which will
-map/unmap a single memory region, and one which will map/unmap a
-scatterlist.
-
-To map a single region, you do:
-
-	struct device *dev = &my_dev->dev;
-	dma_addr_t dma_handle;
-	void *addr = buffer->ptr;
-	size_t size = buffer->len;
-
-	dma_handle = dma_map_single(dev, addr, size, direction);
-
-and to unmap it:
-
-	dma_unmap_single(dev, dma_handle, size, direction);
-
-You should call dma_unmap_single when the DMA activity is finished, e.g.
-from the interrupt which told you that the DMA transfer is done.
-
-Using cpu pointers like this for single mappings has a disadvantage,
-you cannot reference HIGHMEM memory in this way.  Thus, there is a
-map/unmap interface pair akin to dma_{map,unmap}_single.  These
-interfaces deal with page/offset pairs instead of cpu pointers.
-Specifically:
-
-	struct device *dev = &my_dev->dev;
-	dma_addr_t dma_handle;
-	struct page *page = buffer->page;
-	unsigned long offset = buffer->offset;
-	size_t size = buffer->len;
-
-	dma_handle = dma_map_page(dev, page, offset, size, direction);
-
-	...
-
-	dma_unmap_page(dev, dma_handle, size, direction);
-
-Here, "offset" means byte offset within the given page.
-
-With scatterlists, you map a region gathered from several regions by:
-
-	int i, count = dma_map_sg(dev, sglist, nents, direction);
-	struct scatterlist *sg;
-
-	for_each_sg(sglist, sg, count, i) {
-		hw_address[i] = sg_dma_address(sg);
-		hw_len[i] = sg_dma_len(sg);
-	}
-
-where nents is the number of entries in the sglist.
-
-The implementation is free to merge several consecutive sglist entries
-into one (e.g. if DMA mapping is done with PAGE_SIZE granularity, any
-consecutive sglist entries can be merged into one provided the first one
-ends and the second one starts on a page boundary - in fact this is a huge
-advantage for cards which either cannot do scatter-gather or have very
-limited number of scatter-gather entries) and returns the actual number
-of sg entries it mapped them to. On failure 0 is returned.
-
-Then you should loop count times (note: this can be less than nents times)
-and use sg_dma_address() and sg_dma_len() macros where you previously
-accessed sg->address and sg->length as shown above.
-
-To unmap a scatterlist, just call:
-
-	dma_unmap_sg(dev, sglist, nents, direction);
-
-Again, make sure DMA activity has already finished.
-
-PLEASE NOTE:  The 'nents' argument to the dma_unmap_sg call must be
-              the _same_ one you passed into the dma_map_sg call,
-	      it should _NOT_ be the 'count' value _returned_ from the
-              dma_map_sg call.
-
-Every dma_map_{single,sg} call should have its dma_unmap_{single,sg}
-counterpart, because the bus address space is a shared resource (although
-in some ports the mapping is per each BUS so less devices contend for the
-same bus address space) and you could render the machine unusable by eating
-all bus addresses.
-
-If you need to use the same streaming DMA region multiple times and touch
-the data in between the DMA transfers, the buffer needs to be synced
-properly in order for the cpu and device to see the most uptodate and
-correct copy of the DMA buffer.
-
-So, firstly, just map it with dma_map_{single,sg}, and after each DMA
-transfer call either:
-
-	dma_sync_single_for_cpu(dev, dma_handle, size, direction);
-
-or:
-
-	dma_sync_sg_for_cpu(dev, sglist, nents, direction);
-
-as appropriate.
-
-Then, if you wish to let the device get at the DMA area again,
-finish accessing the data with the cpu, and then before actually
-giving the buffer to the hardware call either:
-
-	dma_sync_single_for_device(dev, dma_handle, size, direction);
-
-or:
-
-	dma_sync_sg_for_device(dev, sglist, nents, direction);
-
-as appropriate.
-
-After the last DMA transfer call one of the DMA unmap routines
-dma_unmap_{single,sg}. If you don't touch the data from the first dma_map_*
-call till dma_unmap_*, then you don't have to call the dma_sync_*
-routines at all.
-
-Here is pseudo code which shows a situation in which you would need
-to use the dma_sync_*() interfaces.
-
-	my_card_setup_receive_buffer(struct my_card *cp, char *buffer, int len)
-	{
-		dma_addr_t mapping;
-
-		mapping = dma_map_single(cp->dev, buffer, len, DMA_FROM_DEVICE);
-
-		cp->rx_buf = buffer;
-		cp->rx_len = len;
-		cp->rx_dma = mapping;
-
-		give_rx_buf_to_card(cp);
-	}
-
-	...
-
-	my_card_interrupt_handler(int irq, void *devid, struct pt_regs *regs)
-	{
-		struct my_card *cp = devid;
-
-		...
-		if (read_card_status(cp) == RX_BUF_TRANSFERRED) {
-			struct my_card_header *hp;
-
-			/* Examine the header to see if we wish
-			 * to accept the data.  But synchronize
-			 * the DMA transfer with the CPU first
-			 * so that we see updated contents.
-			 */
-			dma_sync_single_for_cpu(&cp->dev, cp->rx_dma,
-						cp->rx_len,
-						DMA_FROM_DEVICE);
-
-			/* Now it is safe to examine the buffer. */
-			hp = (struct my_card_header *) cp->rx_buf;
-			if (header_is_ok(hp)) {
-				dma_unmap_single(&cp->dev, cp->rx_dma, cp->rx_len,
-						 DMA_FROM_DEVICE);
-				pass_to_upper_layers(cp->rx_buf);
-				make_and_setup_new_rx_buf(cp);
-			} else {
-				/* Just sync the buffer and give it back
-				 * to the card.
-				 */
-				dma_sync_single_for_device(&cp->dev,
-							   cp->rx_dma,
-							   cp->rx_len,
-							   DMA_FROM_DEVICE);
-				give_rx_buf_to_card(cp);
-			}
-		}
-	}
-
-Drivers converted fully to this interface should not use virt_to_bus any
-longer, nor should they use bus_to_virt. Some drivers have to be changed a
-little bit, because there is no longer an equivalent to bus_to_virt in the
-dynamic DMA mapping scheme - you have to always store the DMA addresses
-returned by the dma_alloc_coherent, dma_pool_alloc, and dma_map_single
-calls (dma_map_sg stores them in the scatterlist itself if the platform
-supports dynamic DMA mapping in hardware) in your driver structures and/or
-in the card registers.
-
-All drivers should be using these interfaces with no exceptions.  It
-is planned to completely remove virt_to_bus() and bus_to_virt() as
-they are entirely deprecated.  Some ports already do not provide these
-as it is impossible to correctly support them.
-
-		Optimizing Unmap State Space Consumption
-
-On many platforms, dma_unmap_{single,page}() is simply a nop.
-Therefore, keeping track of the mapping address and length is a waste
-of space.  Instead of filling your drivers up with ifdefs and the like
-to "work around" this (which would defeat the whole purpose of a
-portable API) the following facilities are provided.
-
-Actually, instead of describing the macros one by one, we'll
-transform some example code.
-
-1) Use DEFINE_DMA_UNMAP_{ADDR,LEN} in state saving structures.
-   Example, before:
-
-	struct ring_state {
-		struct sk_buff *skb;
-		dma_addr_t mapping;
-		__u32 len;
-	};
-
-   after:
-
-	struct ring_state {
-		struct sk_buff *skb;
-		DEFINE_DMA_UNMAP_ADDR(mapping);
-		DEFINE_DMA_UNMAP_LEN(len);
-	};
-
-2) Use dma_unmap_{addr,len}_set to set these values.
-   Example, before:
-
-	ringp->mapping = FOO;
-	ringp->len = BAR;
-
-   after:
-
-	dma_unmap_addr_set(ringp, mapping, FOO);
-	dma_unmap_len_set(ringp, len, BAR);
-
-3) Use dma_unmap_{addr,len} to access these values.
-   Example, before:
-
-	dma_unmap_single(dev, ringp->mapping, ringp->len,
-			 DMA_FROM_DEVICE);
-
-   after:
-
-	dma_unmap_single(dev,
-			 dma_unmap_addr(ringp, mapping),
-			 dma_unmap_len(ringp, len),
-			 DMA_FROM_DEVICE);
-
-It really should be self-explanatory.  We treat the ADDR and LEN
-separately, because it is possible for an implementation to only
-need the address in order to perform the unmap operation.
-
-			Platform Issues
-
-If you are just writing drivers for Linux and do not maintain
-an architecture port for the kernel, you can safely skip down
-to "Closing".
-
-1) Struct scatterlist requirements.
-
-   Struct scatterlist must contain, at a minimum, the following
-   members:
-
-	struct page *page;
-	unsigned int offset;
-	unsigned int length;
-
-   The base address is specified by a "page+offset" pair.
-
-   Previous versions of struct scatterlist contained a "void *address"
-   field that was sometimes used instead of page+offset.  As of Linux
-   2.5., page+offset is always used, and the "address" field has been
-   deleted.
-
-2) More to come...
-
-			Handling Errors
-
-DMA address space is limited on some architectures and an allocation
-failure can be determined by:
-
-- checking if dma_alloc_coherent returns NULL or dma_map_sg returns 0
-
-- checking the returned dma_addr_t of dma_map_single and dma_map_page
-  by using dma_mapping_error():
-
-	dma_addr_t dma_handle;
-
-	dma_handle = dma_map_single(dev, addr, size, direction);
-	if (dma_mapping_error(dev, dma_handle)) {
-		/*
-		 * reduce current DMA mapping usage,
-		 * delay and try again later or
-		 * reset driver.
-		 */
-	}
-
-			   Closing
-
-This document, and the API itself, would not be in it's current
-form without the feedback and suggestions from numerous individuals.
-We would like to specifically mention, in no particular order, the
-following people:
-
-	Russell King <rmk@arm.linux.org.uk>
-	Leo Dagum <dagum@barrel.engr.sgi.com>
-	Ralf Baechle <ralf@oss.sgi.com>
-	Grant Grundler <grundler@cup.hp.com>
-	Jay Estabrook <Jay.Estabrook@compaq.com>
-	Thomas Sailer <sailer@ife.ee.ethz.ch>
-	Andrea Arcangeli <andrea@suse.de>
-	Jens Axboe <jens.axboe@oracle.com>
-	David Mosberger-Tang <davidm@hpl.hp.com>

Documentation/PCI/pci-error-recovery.txt

@@ -216,7 +216,7 @@ The driver should return one of the following result codes:
 
 		- PCI_ERS_RESULT_NEED_RESET
 		  Driver returns this if it thinks the device is not
-		  recoverable in it's current state and it needs a slot
+		  recoverable in its current state and it needs a slot
 		  reset to proceed.
 
 		- PCI_ERS_RESULT_DISCONNECT
@@ -241,7 +241,7 @@ in working condition.
 
 The driver is not supposed to restart normal driver I/O operations
 at this point.  It should limit itself to "probing" the device to
-check it's recoverability status. If all is right, then the platform
+check its recoverability status. If all is right, then the platform
 will call resume() once all drivers have ack'd link_reset().
 
 	Result codes:

Documentation/PCI/pcieaer-howto.txt

@@ -13,7 +13,7 @@ Reporting (AER) driver and provides information on how to use it, as
 well as how to enable the drivers of endpoint devices to conform with
 PCI Express AER driver.
 
-1.2 Copyright © Intel Corporation 2006.
+1.2 Copyright (C) Intel Corporation 2006.
 
 1.3 What is the PCI Express AER Driver?
 
@@ -71,15 +71,11 @@ console. If it's a correctable error, it is outputed as a warning.
 Otherwise, it is printed as an error. So users could choose different
 log level to filter out correctable error messages.
 
-Below shows an example.
-+------ PCI-Express Device Error -----+
-Error Severity          : Uncorrected (Fatal)
-PCIE Bus Error type     : Transaction Layer
-Unsupported Request     : First
-Requester ID            : 0500
-VendorID=8086h, DeviceID=0329h, Bus=05h, Device=00h, Function=00h
-TLB Header:
-04000001 00200a03 05010000 00050100
+Below shows an example:
+0000:50:00.0: PCIe Bus Error: severity=Uncorrected (Fatal), type=Transaction Layer, id=0500(Requester ID)
+0000:50:00.0:   device [8086:0329] error status/mask=00100000/00000000
+0000:50:00.0:    [20] Unsupported Request    (First)
+0000:50:00.0:   TLP Header: 04000001 00200a03 05010000 00050100
 
 In the example, 'Requester ID' means the ID of the device who sends
 the error message to root port. Pls. refer to pci express specs for
@@ -112,7 +108,7 @@ but the PCI Express link itself is fully functional. Fatal errors, on
 the other hand, cause the link to be unreliable.
 
 When AER is enabled, a PCI Express device will automatically send an
-error message to the PCIE root port above it when the device captures
+error message to the PCIe root port above it when the device captures
 an error. The Root Port, upon receiving an error reporting message,
 internally processes and logs the error message in its PCI Express
 capability structure. Error information being logged includes storing
@@ -198,8 +194,9 @@ to reset link, AER port service driver is required to provide the
 function to reset link. Firstly, kernel looks for if the upstream
 component has an aer driver. If it has, kernel uses the reset_link
 callback of the aer driver. If the upstream component has no aer driver
-and the port is downstream port, we will use the aer driver of the
-root port who reports the AER error. As for upstream ports,
+and the port is downstream port, we will perform a hot reset as the
+default by setting the Secondary Bus Reset bit of the Bridge Control
+register associated with the downstream port. As for upstream ports,
 they should provide their own aer service drivers with reset_link
 function. If error_detected returns PCI_ERS_RESULT_CAN_RECOVER and
 reset_link returns PCI_ERS_RESULT_RECOVERED, the error handling goes
@@ -253,11 +250,11 @@ cleanup uncorrectable status register. Pls. refer to section 3.3.
 
 4. Software error injection
 
-Debugging PCIE AER error recovery code is quite difficult because it
+Debugging PCIe AER error recovery code is quite difficult because it
 is hard to trigger real hardware errors. Software based error
-injection can be used to fake various kinds of PCIE errors.
+injection can be used to fake various kinds of PCIe errors.
 
-First you should enable PCIE AER software error injection in kernel
+First you should enable PCIe AER software error injection in kernel
 configuration, that is, following item should be in your .config.
 
 CONFIG_PCIEAER_INJECT=y or CONFIG_PCIEAER_INJECT=m

Documentation/RCU/NMI-RCU.txt

@@ -34,7 +34,7 @@ NMI handler.
 		cpu = smp_processor_id();
 		++nmi_count(cpu);
 
-		if (!rcu_dereference(nmi_callback)(regs, cpu))
+		if (!rcu_dereference_sched(nmi_callback)(regs, cpu))
 			default_do_nmi(regs);
 
 		nmi_exit();
@@ -47,12 +47,13 @@ function pointer.  If this handler returns zero, do_nmi() invokes the
 default_do_nmi() function to handle a machine-specific NMI.  Finally,
 preemption is restored.
 
-Strictly speaking, rcu_dereference() is not needed, since this code runs
-only on i386, which does not need rcu_dereference() anyway.  However,
-it is a good documentation aid, particularly for anyone attempting to
-do something similar on Alpha.
+In theory, rcu_dereference_sched() is not needed, since this code runs
+only on i386, which in theory does not need rcu_dereference_sched()
+anyway.  However, in practice it is a good documentation aid, particularly
+for anyone attempting to do something similar on Alpha or on systems
+with aggressive optimizing compilers.
 
-Quick Quiz:  Why might the rcu_dereference() be necessary on Alpha,
+Quick Quiz:  Why might the rcu_dereference_sched() be necessary on Alpha,
 	     given that the code referenced by the pointer is read-only?
 
 
@@ -99,17 +100,21 @@ invoke irq_enter() and irq_exit() on NMI entry and exit, respectively.
 
 Answer to Quick Quiz
 
-	Why might the rcu_dereference() be necessary on Alpha, given
+	Why might the rcu_dereference_sched() be necessary on Alpha, given
 	that the code referenced by the pointer is read-only?
 
 	Answer: The caller to set_nmi_callback() might well have
-		initialized some data that is to be used by the
-		new NMI handler.  In this case, the rcu_dereference()
-		would be needed, because otherwise a CPU that received
-		an NMI just after the new handler was set might see
-		the pointer to the new NMI handler, but the old
-		pre-initialized version of the handler's data.
-
-		More important, the rcu_dereference() makes it clear
-		to someone reading the code that the pointer is being
-		protected by RCU.
+		initialized some data that is to be used by the new NMI
+		handler.  In this case, the rcu_dereference_sched() would
+		be needed, because otherwise a CPU that received an NMI
+		just after the new handler was set might see the pointer
+		to the new NMI handler, but the old pre-initialized
+		version of the handler's data.
+
+		This same sad story can happen on other CPUs when using
+		a compiler with aggressive pointer-value speculation
+		optimizations.
+
+		More important, the rcu_dereference_sched() makes it
+		clear to someone reading the code that the pointer is
+		being protected by RCU-sched.

Documentation/RCU/checklist.txt

@@ -260,7 +260,8 @@ over a rather long period of time, but improvements are always welcome!
 	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.
+	shared between readers and updaters.  Additional primitives
+	are provided for this case, as discussed in lockdep.txt.
 
 10.	Conversely, if you are in an RCU read-side critical section,
 	and you don't hold the appropriate update-side lock, you -must-
@@ -344,8 +345,8 @@ over a rather long period of time, but improvements are always welcome!
 	requiring SRCU's read-side deadlock immunity or low read-side
 	realtime latency.
 
-	Note that, rcu_assign_pointer() and rcu_dereference() relate to
-	SRCU just as they do to other forms of RCU.
+	Note that, rcu_assign_pointer() relates to SRCU just as they do
+	to other forms of RCU.
 
 15.	The whole point of call_rcu(), synchronize_rcu(), and friends
 	is to wait until all pre-existing readers have finished before

Documentation/RCU/lockdep.txt

@@ -32,9 +32,20 @@ checking of rcu_dereference() primitives:
 	srcu_dereference(p, sp):
 		Check for SRCU read-side critical section.
 	rcu_dereference_check(p, c):
-		Use explicit check expression "c".
+		Use explicit check expression "c".  This is useful in
+		code that is invoked by both readers and updaters.
 	rcu_dereference_raw(p)
 		Don't check.  (Use sparingly, if at all.)
+	rcu_dereference_protected(p, c):
+		Use explicit check expression "c", and omit all barriers
+		and compiler constraints.  This is useful when the data
+		structure cannot change, for example, in code that is
+		invoked only by updaters.
+	rcu_access_pointer(p):
+		Return the value of the pointer and omit all barriers,
+		but retain the compiler constraints that prevent duplicating
+		or coalescsing.  This is useful when when testing the
+		value of the pointer itself, for example, against NULL.
 
 The rcu_dereference_check() check expression can be any boolean
 expression, but would normally include one of the rcu_read_lock_held()
@@ -59,7 +70,20 @@ In case (1), the pointer is picked up in an RCU-safe manner for vanilla
 RCU read-side critical sections, in case (2) the ->file_lock prevents
 any change from taking place, and finally, in case (3) the current task
 is the only task accessing the file_struct, again preventing any change
-from taking place.
+from taking place.  If the above statement was invoked only from updater
+code, it could instead be written as follows:
+
+	file = rcu_dereference_protected(fdt->fd[fd],
+					 lockdep_is_held(&files->file_lock) ||
+					 atomic_read(&files->count) == 1);
+
+This would verify cases #2 and #3 above, and furthermore lockdep would
+complain if this was used in an RCU read-side critical section unless one
+of these two cases held.  Because rcu_dereference_protected() omits all
+barriers and compiler constraints, it generates better code than do the
+other flavors of rcu_dereference().  On the other hand, it is illegal
+to use rcu_dereference_protected() if either the RCU-protected pointer
+or the RCU-protected data that it points to can change concurrently.
 
 There are currently only "universal" versions of the rcu_assign_pointer()
 and RCU list-/tree-traversal primitives, which do not (yet) check for

Documentation/RCU/stallwarn.txt

@@ -3,35 +3,79 @@ Using RCU's CPU Stall Detector
 The CONFIG_RCU_CPU_STALL_DETECTOR kernel config parameter enables
 RCU's CPU stall detector, which detects conditions that unduly delay
 RCU grace periods.  The stall detector's idea of what constitutes
-"unduly delayed" is controlled by a pair of C preprocessor macros:
+"unduly delayed" is controlled by a set of C preprocessor macros:
 
 RCU_SECONDS_TILL_STALL_CHECK
 
 	This macro defines the period of time that RCU will wait from
 	the beginning of a grace period until it issues an RCU CPU
-	stall warning.	It is normally ten seconds.
+	stall warning.	This time period is normally ten seconds.
 
 RCU_SECONDS_TILL_STALL_RECHECK
 
 	This macro defines the period of time that RCU will wait after
-	issuing a stall warning until it issues another stall warning.
-	It is normally set to thirty seconds.
+	issuing a stall warning until it issues another stall warning
+	for the same stall.  This time period is normally set to thirty
+	seconds.
 
 RCU_STALL_RAT_DELAY
 
-	The CPU stall detector tries to make the offending CPU rat on itself,
-	as this often gives better-quality stack traces.  However, if
-	the offending CPU does not detect its own stall in the number
-	of jiffies specified by RCU_STALL_RAT_DELAY, then other CPUs will
-	complain.  This is normally set to two jiffies.
+	The CPU stall detector tries to make the offending CPU print its
+	own warnings, as this often gives better-quality stack traces.
+	However, if the offending CPU does not detect its own stall in
+	the number of jiffies specified by RCU_STALL_RAT_DELAY, then
+	some other CPU will complain.  This delay is normally set to
+	two jiffies.
 
-The following problems can result in an RCU CPU stall warning:
+When a CPU detects that it is stalling, it will print a message similar
+to the following:
+
+INFO: rcu_sched_state detected stall on CPU 5 (t=2500 jiffies)
+
+This message indicates that CPU 5 detected that it was causing a stall,
+and that the stall was affecting RCU-sched.  This message will normally be
+followed by a stack dump of the offending CPU.  On TREE_RCU kernel builds,
+RCU and RCU-sched are implemented by the same underlying mechanism,
+while on TREE_PREEMPT_RCU kernel builds, RCU is instead implemented
+by rcu_preempt_state.
+
+On the other hand, if the offending CPU fails to print out a stall-warning
+message quickly enough, some other CPU will print a message similar to
+the following:
+
+INFO: rcu_bh_state detected stalls on CPUs/tasks: { 3 5 } (detected by 2, 2502 jiffies)
+
+This message indicates that CPU 2 detected that CPUs 3 and 5 were both
+causing stalls, and that the stall was affecting RCU-bh.  This message
+will normally be followed by stack dumps for each CPU.  Please note that
+TREE_PREEMPT_RCU builds can be stalled by tasks as well as by CPUs,
+and that the tasks will be indicated by PID, for example, "P3421".
+It is even possible for a rcu_preempt_state stall to be caused by both
+CPUs -and- tasks, in which case the offending CPUs and tasks will all
+be called out in the list.
+
+Finally, if the grace period ends just as the stall warning starts
+printing, there will be a spurious stall-warning message:
+
+INFO: rcu_bh_state detected stalls on CPUs/tasks: { } (detected by 4, 2502 jiffies)
+
+This is rare, but does happen from time to time in real life.
+
+So your kernel printed an RCU CPU stall warning.  The next question is
+"What caused it?"  The following problems can result in RCU CPU stall
+warnings:
 
 o	A CPU looping in an RCU read-side critical section.
 	
-o	A CPU looping with interrupts disabled.
+o	A CPU looping with interrupts disabled.  This condition can
+	result in RCU-sched and RCU-bh stalls.
 
-o	A CPU looping with preemption disabled.
+o	A CPU looping with preemption disabled.  This condition can
+	result in RCU-sched stalls and, if ksoftirqd is in use, RCU-bh
+	stalls.
+
+o	A CPU looping with bottom halves disabled.  This condition can
+	result in RCU-sched and RCU-bh stalls.
 
 o	For !CONFIG_PREEMPT kernels, a CPU looping anywhere in the kernel
 	without invoking schedule().
@@ -39,20 +83,24 @@ o	For !CONFIG_PREEMPT kernels, a CPU looping anywhere in the kernel
 o	A bug in the RCU implementation.
 
 o	A hardware failure.  This is quite unlikely, but has occurred
-	at least once in a former life.  A CPU failed in a running system,
+	at least once in real life.  A CPU failed in a running system,
 	becoming unresponsive, but not causing an immediate crash.
 	This resulted in a series of RCU CPU stall warnings, eventually
 	leading the realization that the CPU had failed.
 
-The RCU, RCU-sched, and RCU-bh implementations have CPU stall warning.
-SRCU does not do so directly, but its calls to synchronize_sched() will
-result in RCU-sched detecting any CPU stalls that might be occurring.
-
-To diagnose the cause of the stall, inspect the stack traces.  The offending
-function will usually be near the top of the stack.  If you have a series
-of stall warnings from a single extended stall, comparing the stack traces
-can often help determine where the stall is occurring, which will usually
-be in the function nearest the top of the stack that stays the same from
-trace to trace.
+The RCU, RCU-sched, and RCU-bh implementations have CPU stall
+warning.  SRCU does not have its own CPU stall warnings, but its
+calls to synchronize_sched() will result in RCU-sched detecting
+RCU-sched-related CPU stalls.  Please note that RCU only detects
+CPU stalls when there is a grace period in progress.  No grace period,
+no CPU stall warnings.
+
+To diagnose the cause of the stall, inspect the stack traces.
+The offending function will usually be near the top of the stack.
+If you have a series of stall warnings from a single extended stall,
+comparing the stack traces can often help determine where the stall
+is occurring, which will usually be in the function nearest the top of
+that portion of the stack which remains the same from trace to trace.
+If you can reliably trigger the stall, ftrace can be quite helpful.
 
 RCU bugs can often be debugged with the help of CONFIG_RCU_TRACE.

Documentation/RCU/torture.txt

@@ -182,16 +182,6 @@ Similarly, sched_expedited RCU provides the following:
 	sched_expedited-torture: Reader Pipe:  12660320201 95875 0 0 0 0 0 0 0 0 0
 	sched_expedited-torture: Reader Batch:  12660424885 0 0 0 0 0 0 0 0 0 0
 	sched_expedited-torture: Free-Block Circulation:  1090795 1090795 1090794 1090793 1090792 1090791 1090790 1090789 1090788 1090787 0
-	state: -1 / 0:0 3:0 4:0
-
-As before, the first four lines are similar to those for RCU.
-The last line shows the task-migration state.  The first number is
--1 if synchronize_sched_expedited() is idle, -2 if in the process of
-posting wakeups to the migration kthreads, and N when waiting on CPU N.
-Each of the colon-separated fields following the "/" is a CPU:state pair.
-Valid states are "0" for idle, "1" for waiting for quiescent state,
-"2" for passed through quiescent state, and "3" when a race with a
-CPU-hotplug event forces use of the synchronize_sched() primitive.
 
 
 USAGE

Documentation/RCU/trace.txt

@@ -256,23 +256,23 @@ o	Each element of the form "1/1 0:127 ^0" represents one struct
 The output of "cat rcu/rcu_pending" looks as follows:
 
 rcu_sched:
-  0 np=255892 qsp=53936 cbr=0 cng=14417 gpc=10033 gps=24320 nf=6445 nn=146741
-  1 np=261224 qsp=54638 cbr=0 cng=25723 gpc=16310 gps=2849 nf=5912 nn=155792
-  2 np=237496 qsp=49664 cbr=0 cng=2762 gpc=45478 gps=1762 nf=1201 nn=136629
-  3 np=236249 qsp=48766 cbr=0 cng=286 gpc=48049 gps=1218 nf=207 nn=137723
-  4 np=221310 qsp=46850 cbr=0 cng=26 gpc=43161 gps=4634 nf=3529 nn=123110
-  5 np=237332 qsp=48449 cbr=0 cng=54 gpc=47920 gps=3252 nf=201 nn=137456
-  6 np=219995 qsp=46718 cbr=0 cng=50 gpc=42098 gps=6093 nf=4202 nn=120834
-  7 np=249893 qsp=49390 cbr=0 cng=72 gpc=38400 gps=17102 nf=41 nn=144888
+  0 np=255892 qsp=53936 rpq=85 cbr=0 cng=14417 gpc=10033 gps=24320 nf=6445 nn=146741
+  1 np=261224 qsp=54638 rpq=33 cbr=0 cng=25723 gpc=16310 gps=2849 nf=5912 nn=155792
+  2 np=237496 qsp=49664 rpq=23 cbr=0 cng=2762 gpc=45478 gps=1762 nf=1201 nn=136629
+  3 np=236249 qsp=48766 rpq=98 cbr=0 cng=286 gpc=48049 gps=1218 nf=207 nn=137723
+  4 np=221310 qsp=46850 rpq=7 cbr=0 cng=26 gpc=43161 gps=4634 nf=3529 nn=123110
+  5 np=237332 qsp=48449 rpq=9 cbr=0 cng=54 gpc=47920 gps=3252 nf=201 nn=137456
+  6 np=219995 qsp=46718 rpq=12 cbr=0 cng=50 gpc=42098 gps=6093 nf=4202 nn=120834
+  7 np=249893 qsp=49390 rpq=42 cbr=0 cng=72 gpc=38400 gps=17102 nf=41 nn=144888
 rcu_bh:
-  0 np=146741 qsp=1419 cbr=0 cng=6 gpc=0 gps=0 nf=2 nn=145314
-  1 np=155792 qsp=12597 cbr=0 cng=0 gpc=4 gps=8 nf=3 nn=143180
-  2 np=136629 qsp=18680 cbr=0 cng=0 gpc=7 gps=6 nf=0 nn=117936
-  3 np=137723 qsp=2843 cbr=0 cng=0 gpc=10 gps=7 nf=0 nn=134863
-  4 np=123110 qsp=12433 cbr=0 cng=0 gpc=4 gps=2 nf=0 nn=110671
-  5 np=137456 qsp=4210 cbr=0 cng=0 gpc=6 gps=5 nf=0 nn=133235
-  6 np=120834 qsp=9902 cbr=0 cng=0 gpc=6 gps=3 nf=2 nn=110921
-  7 np=144888 qsp=26336 cbr=0 cng=0 gpc=8 gps=2 nf=0 nn=118542
+  0 np=146741 qsp=1419 rpq=6 cbr=0 cng=6 gpc=0 gps=0 nf=2 nn=145314
+  1 np=155792 qsp=12597 rpq=3 cbr=0 cng=0 gpc=4 gps=8 nf=3 nn=143180
+  2 np=136629 qsp=18680 rpq=1 cbr=0 cng=0 gpc=7 gps=6 nf=0 nn=117936
+  3 np=137723 qsp=2843 rpq=0 cbr=0 cng=0 gpc=10 gps=7 nf=0 nn=134863
+  4 np=123110 qsp=12433 rpq=0 cbr=0 cng=0 gpc=4 gps=2 nf=0 nn=110671
+  5 np=137456 qsp=4210 rpq=1 cbr=0 cng=0 gpc=6 gps=5 nf=0 nn=133235
+  6 np=120834 qsp=9902 rpq=2 cbr=0 cng=0 gpc=6 gps=3 nf=2 nn=110921
+  7 np=144888 qsp=26336 rpq=0 cbr=0 cng=0 gpc=8 gps=2 nf=0 nn=118542
 
 As always, this is once again split into "rcu_sched" and "rcu_bh"
 portions, with CONFIG_TREE_PREEMPT_RCU kernels having an additional
@@ -284,6 +284,9 @@ o	"np" is the number of times that __rcu_pending() has been invoked
 o	"qsp" is the number of times that the RCU was waiting for a
 	quiescent state from this CPU.
 
+o	"rpq" is the number of times that the CPU had passed through
+	a quiescent state, but not yet reported it to RCU.
+
 o	"cbr" is the number of times that this CPU had RCU callbacks
 	that had passed through a grace period, and were thus ready
 	to be invoked.

Documentation/RCU/whatisRCU.txt

@@ -840,6 +840,12 @@ SRCU:	Initialization/cleanup
 	init_srcu_struct
 	cleanup_srcu_struct
 
+All:  lockdep-checked RCU-protected pointer access
+
+	rcu_dereference_check
+	rcu_dereference_protected
+	rcu_access_pointer
+
 See the comment headers in the source code (or the docbook generated
 from them) for more information.
 

Documentation/Smack.txt

@@ -73,7 +73,7 @@ NOTE: Smack labels are limited to 23 characters. The attr command
 If you don't do anything special all users will get the floor ("_")
 label when they log in. If you do want to log in via the hacked ssh
 at other labels use the attr command to set the smack value on the
-home directory and it's contents.
+home directory and its contents.
 
 You can add access rules in /etc/smack/accesses. They take the form:
 

Documentation/SubmitChecklist

@@ -18,6 +18,8 @@ kernel patches.
 
 2b: Passes allnoconfig, allmodconfig
 
+2c: Builds successfully when using O=builddir
+
 3: Builds on multiple CPU architectures by using local cross-compile tools
    or some other build farm.
 
@@ -95,3 +97,13 @@ kernel patches.
 
 25: If any ioctl's are added by the patch, then also update
     Documentation/ioctl/ioctl-number.txt.
+
+26: If your modified source code depends on or uses any of the kernel
+    APIs or features that are related to the following kconfig symbols,
+    then test multiple builds with the related kconfig symbols disabled
+    and/or =m (if that option is available) [not all of these at the
+    same time, just various/random combinations of them]:
+
+    CONFIG_SMP, CONFIG_SYSFS, CONFIG_PROC_FS, CONFIG_INPUT, CONFIG_PCI,
+    CONFIG_BLOCK, CONFIG_PM, CONFIG_HOTPLUG, CONFIG_MAGIC_SYSRQ,
+    CONFIG_NET, CONFIG_INET=n (but latter with CONFIG_NET=y)

Documentation/SubmittingDrivers

@@ -130,6 +130,8 @@ Linux kernel master tree:
 	ftp.??.kernel.org:/pub/linux/kernel/...
 	?? == your country code, such as "us", "uk", "fr", etc.
 
+	http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git
+
 Linux kernel mailing list:
 	linux-kernel@vger.kernel.org
 	[mail majordomo@vger.kernel.org to subscribe]
@@ -160,3 +162,6 @@ How to NOT write kernel driver by Arjan van de Ven:
 
 Kernel Janitor:
 	http://janitor.kernelnewbies.org/
+
+GIT, Fast Version Control System:
+	http://git-scm.com/

Documentation/acpi/apei/einj.txt

@@ -0,0 +1,59 @@
+			APEI Error INJection
+			~~~~~~~~~~~~~~~~~~~~
+
+EINJ provides a hardware error injection mechanism
+It is very useful for debugging and testing of other APEI and RAS features.
+
+To use EINJ, make sure the following are enabled in your kernel
+configuration:
+
+CONFIG_DEBUG_FS
+CONFIG_ACPI_APEI
+CONFIG_ACPI_APEI_EINJ
+
+The user interface of EINJ is debug file system, under the
+directory apei/einj. The following files are provided.
+
+- available_error_type
+  Reading this file returns the error injection capability of the
+  platform, that is, which error types are supported. The error type
+  definition is as follow, the left field is the error type value, the
+  right field is error description.
+
+    0x00000001	Processor Correctable
+    0x00000002	Processor Uncorrectable non-fatal
+    0x00000004	Processor Uncorrectable fatal
+    0x00000008  Memory Correctable
+    0x00000010  Memory Uncorrectable non-fatal
+    0x00000020  Memory Uncorrectable fatal
+    0x00000040	PCI Express Correctable
+    0x00000080	PCI Express Uncorrectable fatal
+    0x00000100	PCI Express Uncorrectable non-fatal
+    0x00000200	Platform Correctable
+    0x00000400	Platform Uncorrectable non-fatal
+    0x00000800	Platform Uncorrectable fatal
+
+  The format of file contents are as above, except there are only the
+  available error type lines.
+
+- error_type
+  This file is used to set the error type value. The error type value
+  is defined in "available_error_type" description.
+
+- error_inject
+  Write any integer to this file to trigger the error
+  injection. Before this, please specify all necessary error
+  parameters.
+
+- param1
+  This file is used to set the first error parameter value. Effect of
+  parameter depends on error_type specified. For memory error, this is
+  physical memory address.
+
+- param2
+  This file is used to set the second error parameter value. Effect of
+  parameter depends on error_type specified. For memory error, this is
+  physical memory address mask.
+
+For more information about EINJ, please refer to ACPI specification
+version 4.0, section 17.5.

Documentation/arm/00-INDEX

@@ -20,6 +20,8 @@ Samsung-S3C24XX
 	- S3C24XX ARM Linux Overview
 Sharp-LH
 	- Linux on Sharp LH79524 and LH7A40X System On a Chip (SOC)
+SPEAr
+	- ST SPEAr platform Linux Overview
 VFP/
 	- Release notes for Linux Kernel Vector Floating Point support code
 empeg/

Documentation/arm/SA1100/ADSBitsy

@@ -32,7 +32,7 @@ Notes:
 
 - The flash on board is divided into 3 partitions.
   You should be careful to use flash on board.
-  It's partition is different from GraphicsClient Plus and GraphicsMaster
+  Its partition is different from GraphicsClient Plus and GraphicsMaster
 
 - 16bpp mode requires a different cable than what ships with the board.
   Contact ADS or look through the manual to wire your own. Currently,

Documentation/arm/SPEAr/overview.txt

@@ -0,0 +1,60 @@
+			SPEAr ARM Linux Overview
+			==========================
+
+Introduction
+------------
+
+  SPEAr (Structured Processor Enhanced Architecture).
+  weblink : http://www.st.com/spear
+
+  The ST Microelectronics SPEAr range of ARM9/CortexA9 System-on-Chip CPUs are
+  supported by the 'spear' platform of ARM Linux. Currently SPEAr300,
+  SPEAr310, SPEAr320 and SPEAr600 SOCs are supported. Support for the SPEAr13XX
+  series is in progress.
+
+  Hierarchy in SPEAr is as follows:
+
+  SPEAr (Platform)
+	- SPEAr3XX (3XX SOC series, based on ARM9)
+		- SPEAr300 (SOC)
+			- SPEAr300_EVB (Evaluation Board)
+		- SPEAr310 (SOC)
+			- SPEAr310_EVB (Evaluation Board)
+		- SPEAr320 (SOC)
+			- SPEAr320_EVB (Evaluation Board)
+	- SPEAr6XX (6XX SOC series, based on ARM9)
+		- SPEAr600 (SOC)
+			- SPEAr600_EVB (Evaluation Board)
+	- SPEAr13XX (13XX SOC series, based on ARM CORTEXA9)
+		- SPEAr1300 (SOC)
+
+  Configuration
+  -------------
+
+  A generic configuration is provided for each machine, and can be used as the
+  default by
+	make spear600_defconfig
+	make spear300_defconfig
+	make spear310_defconfig
+	make spear320_defconfig
+
+  Layout
+  ------
+
+  The common files for multiple machine families (SPEAr3XX, SPEAr6XX and
+  SPEAr13XX) are located in the platform code contained in arch/arm/plat-spear
+  with headers in plat/.
+
+  Each machine series have a directory with name arch/arm/mach-spear followed by
+  series name. Like mach-spear3xx, mach-spear6xx and mach-spear13xx.
+
+  Common file for machines of spear3xx family is mach-spear3xx/spear3xx.c and for
+  spear6xx is mach-spear6xx/spear6xx.c. mach-spear* also contain soc/machine
+  specific files, like spear300.c, spear310.c, spear320.c and spear600.c.
+  mach-spear* also contains board specific files for each machine type.
+
+
+  Document Author
+  ---------------
+
+  Viresh Kumar, (c) 2010 ST Microelectronics

Documentation/arm/Samsung-S3C24XX/GPIO.txt

@@ -12,6 +12,8 @@ Introduction
   of the s3c2410 GPIO system, please read the Samsung provided
   data-sheet/users manual to find out the complete list.
 
+  See Documentation/arm/Samsung/GPIO.txt for the core implemetation.
+
 
 GPIOLIB
 -------
@@ -24,8 +26,60 @@ GPIOLIB
   listed below will be removed (they may be marked as __deprecated
   in the near future).
 
-  - s3c2410_gpio_getpin
-  - s3c2410_gpio_setpin
+  The following functions now either have a s3c_ specific variant
+  or are merged into gpiolib. See the definitions in
+  arch/arm/plat-samsung/include/plat/gpio-cfg.h:
+
+  s3c2410_gpio_setpin()		gpio_set_value() or gpio_direction_output()
+  s3c2410_gpio_getpin()		gpio_get_value() or gpio_direction_input()
+  s3c2410_gpio_getirq()		gpio_to_irq()
+  s3c2410_gpio_cfgpin()		s3c_gpio_cfgpin()
+  s3c2410_gpio_getcfg()		s3c_gpio_getcfg()
+  s3c2410_gpio_pullup()		s3c_gpio_setpull()
+
+
+GPIOLIB conversion
+------------------
+
+If you need to convert your board or driver to use gpiolib from the exiting
+s3c2410 api, then here are some notes on the process.
+
+1) If your board is exclusively using an GPIO, say to control peripheral
+   power, then it will require to claim the gpio with gpio_request() before
+   it can use it.
+
+   It is recommended to check the return value, with at least WARN_ON()
+   during initialisation.
+
+2) The s3c2410_gpio_cfgpin() can be directly replaced with s3c_gpio_cfgpin()
+   as they have the same arguments, and can either take the pin specific
+   values, or the more generic special-function-number arguments.
+
+3) s3c2410_gpio_pullup() changs have the problem that whilst the 
+   s3c2410_gpio_pullup(x, 1) can be easily translated to the
+   s3c_gpio_setpull(x, S3C_GPIO_PULL_NONE), the s3c2410_gpio_pullup(x, 0)
+   are not so easy.
+
+   The s3c2410_gpio_pullup(x, 0) case enables the pull-up (or in the case
+   of some of the devices, a pull-down) and as such the new API distinguishes
+   between the UP and DOWN case. There is currently no 'just turn on' setting
+   which may be required if this becomes a problem.
+
+4) s3c2410_gpio_setpin() can be replaced by gpio_set_value(), the old call
+   does not implicitly configure the relevant gpio to output. The gpio
+   direction should be changed before using gpio_set_value().
+
+5) s3c2410_gpio_getpin() is replaceable by gpio_get_value() if the pin
+   has been set to input. It is currently unknown what the behaviour is
+   when using gpio_get_value() on an output pin (s3c2410_gpio_getpin
+   would return the value the pin is supposed to be outputting).
+
+6) s3c2410_gpio_getirq() should be directly replacable with the
+   gpio_to_irq() call.
+
+The s3c2410_gpio and gpio_ calls have always operated on the same gpio
+numberspace, so there is no problem with converting the gpio numbering
+between the calls.
 
 
 Headers
@@ -54,6 +108,11 @@ PIN Numbers
   eg S3C2410_GPA(0) or S3C2410_GPF(1). These defines are used to tell
   the GPIO functions which pin is to be used.
 
+  With the conversion to gpiolib, there is no longer a direct conversion
+  from gpio pin number to register base address as in earlier kernels. This
+  is due to the number space required for newer SoCs where the later
+  GPIOs are not contiguous.
+
 
 Configuring a pin
 -----------------
@@ -71,6 +130,8 @@ Configuring a pin
    which would turn GPA(0) into the lowest Address line A0, and set
    GPE(8) to be connected to the SDIO/MMC controller's SDDAT1 line.
 
+   The s3c_gpio_cfgpin() call is a functional replacement for this call.
+
 
 Reading the current configuration
 ---------------------------------
@@ -82,6 +143,9 @@ Reading the current configuration
   The return value will be from the same set of values which can be
   passed to s3c2410_gpio_cfgpin().
 
+  The s3c_gpio_getcfg() call should be a functional replacement for
+  this call.
+
 
 Configuring a pull-up resistor
 ------------------------------
@@ -95,6 +159,10 @@ Configuring a pull-up resistor
   Where the to value is zero to set the pull-up off, and 1 to enable
   the specified pull-up. Any other values are currently undefined.
 
+  The s3c_gpio_setpull() offers similar functionality, but with the
+  ability to encode whether the pull is up or down. Currently there
+  is no 'just on' state, so up or down must be selected.
+
 
 Getting the state of a PIN
 --------------------------
@@ -106,6 +174,9 @@ Getting the state of a PIN
   This will return either zero or non-zero. Do not count on this
   function returning 1 if the pin is set.
 
+  This call is now implemented by the relevant gpiolib calls, convert
+  your board or driver to use gpiolib.
+
 
 Setting the state of a PIN
 --------------------------
@@ -117,6 +188,9 @@ Setting the state of a PIN
   Which sets the given pin to the value. Use 0 to write 0, and 1 to
   set the output to 1.
 
+  This call is now implemented by the relevant gpiolib calls, convert
+  your board or driver to use gpiolib.
+
 
 Getting the IRQ number associated with a PIN
 --------------------------------------------
@@ -128,6 +202,9 @@ Getting the IRQ number associated with a PIN
 
   Note, not all pins have an IRQ.
 
+  This call is now implemented by the relevant gpiolib calls, convert
+  your board or driver to use gpiolib.
+
 
 Authour
 -------

Documentation/arm/Samsung-S3C24XX/Overview.txt

@@ -8,10 +8,16 @@ Introduction
 
   The Samsung S3C24XX range of ARM9 System-on-Chip CPUs are supported
   by the 's3c2410' architecture of ARM Linux. Currently the S3C2410,
-  S3C2412, S3C2413, S3C2440, S3C2442 and S3C2443 devices are supported.
+  S3C2412, S3C2413, S3C2416 S3C2440, S3C2442, S3C2443 and S3C2450 devices
+  are supported.
 
   Support for the S3C2400 and S3C24A0 series are in progress.
 
+  The S3C2416 and S3C2450 devices are very similar and S3C2450 support is
+  included under the arch/arm/mach-s3c2416 directory. Note, whilst core
+  support for these SoCs is in, work on some of the extra peripherals
+  and extra interrupts is still ongoing.
+
 
 Configuration
 -------------
@@ -209,6 +215,13 @@ GPIO
   Newer kernels carry GPIOLIB, and support is being moved towards
   this with some of the older support in line to be removed.
 
+  As of v2.6.34, the move towards using gpiolib support is almost
+  complete, and very little of the old calls are left.
+
+  See Documentation/arm/Samsung-S3C24XX/GPIO.txt for the S3C24XX specific
+  support and Documentation/arm/Samsung/GPIO.txt for the core Samsung
+  implementation.
+
 
 Clock Management
 ----------------

Documentation/arm/Samsung/GPIO.txt

@@ -0,0 +1,42 @@
+		Samsung GPIO implementation
+		===========================
+
+Introduction
+------------
+
+This outlines the Samsung GPIO implementation and the architecture
+specfic calls provided alongisde the drivers/gpio core.
+
+
+S3C24XX (Legacy)
+----------------
+
+See Documentation/arm/Samsung-S3C24XX/GPIO.txt for more information
+about these devices. Their implementation is being brought into line
+with the core samsung implementation described in this document.
+
+
+GPIOLIB integration
+-------------------
+
+The gpio implementation uses gpiolib as much as possible, only providing
+specific calls for the items that require Samsung specific handling, such
+as pin special-function or pull resistor control.
+
+GPIO numbering is synchronised between the Samsung and gpiolib system.
+
+
+PIN configuration
+-----------------
+
+Pin configuration is specific to the Samsung architecutre, with each SoC
+registering the necessary information for the core gpio configuration
+implementation to configure pins as necessary.
+
+The s3c_gpio_cfgpin() and s3c_gpio_setpull() provide the means for a
+driver or machine to change gpio configuration.
+
+See arch/arm/plat-samsung/include/plat/gpio-cfg.h for more information
+on these functions.
+
+

Documentation/arm/Samsung/Overview.txt

@@ -13,9 +13,10 @@ Introduction
 
   - S3C24XX: See Documentation/arm/Samsung-S3C24XX/Overview.txt for full list
   - S3C64XX: S3C6400 and S3C6410
-  - S5PC6440
-
-  S5PC100 and S5PC110 support is currently being merged
+  - S5P6440
+  - S5P6442
+  - S5PC100
+  - S5PC110 / S5PV210
 
 
 S3C24XX Systems
@@ -35,7 +36,10 @@ Configuration
   unifying all the SoCs into one kernel.
 
   s5p6440_defconfig - S5P6440 specific default configuration
+  s5p6442_defconfig - S5P6442 specific default configuration
   s5pc100_defconfig - S5PC100 specific default configuration
+  s5pc110_defconfig - S5PC110 specific default configuration
+  s5pv210_defconfig - S5PV210 specific default configuration
 
 
 Layout
@@ -50,18 +54,27 @@ Layout
   specific information. It contains the base clock, GPIO and device definitions
   to get the system running.
 
-  plat-s3c is the s3c24xx/s3c64xx platform directory, although it is currently
-  involved in other builds this will be phased out once the relevant code is
-  moved elsewhere.
-
   plat-s3c24xx is for s3c24xx specific builds, see the S3C24XX docs.
 
-  plat-s3c64xx is for the s3c64xx specific bits, see the S3C24XX docs.
+  plat-s5p is for s5p specific builds, and contains common support for the
+  S5P specific systems. Not all S5Ps use all the features in this directory
+  due to differences in the hardware.
+
+
+Layout changes
+--------------
+
+  The old plat-s3c and plat-s5pc1xx directories have been removed, with
+  support moved to either plat-samsung or plat-s5p as necessary. These moves
+  where to simplify the include and dependency issues involved with having
+  so many different platform directories.
 
-  plat-s5p is for s5p specific builds, more to be added.
+  It was decided to remove plat-s5pc1xx as some of the support was already
+  in plat-s5p or plat-samsung, with the S5PC110 support added with S5PV210
+  the only user was the S5PC100. The S5PC100 specific items where moved to
+  arch/arm/mach-s5pc100.
 
 
-  [ to finish ]
 
 
 Port Contributors

Documentation/arm/Sharp-LH/ADC-LH7-Touchscreen

@@ -7,7 +7,7 @@ The driver only implements a four-wire touch panel protocol.
 
 The touchscreen driver is maintenance free except for the pen-down or
 touch threshold.  Some resistive displays and board combinations may
-require tuning of this threshold.  The driver exposes some of it's
+require tuning of this threshold.  The driver exposes some of its
 internal state in the sys filesystem.  If the kernel is configured
 with it, CONFIG_SYSFS, and sysfs is mounted at /sys, there will be a
 directory

Documentation/atomic_ops.txt

@@ -320,7 +320,7 @@ counter decrement would not become globally visible until the
 obj->active update does.
 
 As a historical note, 32-bit Sparc used to only allow usage of
-24-bits of it's atomic_t type.  This was because it used 8 bits
+24-bits of its atomic_t type.  This was because it used 8 bits
 as a spinlock for SMP safety.  Sparc32 lacked a "compare and swap"
 type instruction.  However, 32-bit Sparc has since been moved over
 to a "hash table of spinlocks" scheme, that allows the full 32-bit

Documentation/blackfin/bfin-gpio-notes.txt

@@ -43,7 +43,7 @@
 	void bfin_gpio_irq_free(unsigned gpio);
 
     The request functions will record the function state for a certain pin,
-    the free functions will clear it's function state.
+    the free functions will clear its function state.
     Once a pin is requested, it can't be requested again before it is freed by
     previous caller, otherwise kernel will dump stacks, and the request
     function fail.

Documentation/block/biodoc.txt

@@ -1162,8 +1162,8 @@ where a driver received a request ala this before:
 
 As mentioned, there is no virtual mapping of a bio. For DMA, this is
 not a problem as the driver probably never will need a virtual mapping.
-Instead it needs a bus mapping (pci_map_page for a single segment or
-use blk_rq_map_sg for scatter gather) to be able to ship it to the driver. For
+Instead it needs a bus mapping (dma_map_page for a single segment or
+use dma_map_sg for scatter gather) to be able to ship it to the driver. For
 PIO drivers (or drivers that need to revert to PIO transfer once in a
 while (IDE for example)), where the CPU is doing the actual data
 transfer a virtual mapping is needed. If the driver supports highmem I/O,

Documentation/cachetlb.txt

@@ -5,7 +5,7 @@
 
 This document describes the cache/tlb flushing interfaces called
 by the Linux VM subsystem.  It enumerates over each interface,
-describes it's intended purpose, and what side effect is expected
+describes its intended purpose, and what side effect is expected
 after the interface is invoked.
 
 The side effects described below are stated for a uniprocessor
@@ -231,7 +231,7 @@ require a whole different set of interfaces to handle properly.
 The biggest problem is that of virtual aliasing in the data cache
 of a processor.
 
-Is your port susceptible to virtual aliasing in it's D-cache?
+Is your port susceptible to virtual aliasing in its D-cache?
 Well, if your D-cache is virtually indexed, is larger in size than
 PAGE_SIZE, and does not prevent multiple cache lines for the same
 physical address from existing at once, you have this problem.
@@ -249,7 +249,7 @@ one way to solve this (in particular SPARC_FLAG_MMAPSHARED).
 Next, you have to solve the D-cache aliasing issue for all
 other cases.  Please keep in mind that fact that, for a given page
 mapped into some user address space, there is always at least one more
-mapping, that of the kernel in it's linear mapping starting at
+mapping, that of the kernel in its linear mapping starting at
 PAGE_OFFSET.  So immediately, once the first user maps a given
 physical page into its address space, by implication the D-cache
 aliasing problem has the potential to exist since the kernel already

Documentation/cgroups/blkio-controller.txt

@@ -17,6 +17,9 @@ HOWTO
 You can do a very simple testing of running two dd threads in two different
 cgroups. Here is what you can do.
 
+- Enable Block IO controller
+	CONFIG_BLK_CGROUP=y
+
 - Enable group scheduling in CFQ
 	CONFIG_CFQ_GROUP_IOSCHED=y
 
@@ -54,32 +57,52 @@ cgroups. Here is what you can do.
 
 Various user visible config options
 ===================================
-CONFIG_CFQ_GROUP_IOSCHED
-	- Enables group scheduling in CFQ. Currently only 1 level of group
-	  creation is allowed.
-
-CONFIG_DEBUG_CFQ_IOSCHED
-	- Enables some debugging messages in blktrace. Also creates extra
-	  cgroup file blkio.dequeue.
-
-Config options selected automatically
-=====================================
-These config options are not user visible and are selected/deselected
-automatically based on IO scheduler configuration.
-
 CONFIG_BLK_CGROUP
-	- Block IO controller. Selected by CONFIG_CFQ_GROUP_IOSCHED.
+	- Block IO controller.
 
 CONFIG_DEBUG_BLK_CGROUP
-	- Debug help. Selected by CONFIG_DEBUG_CFQ_IOSCHED.
+	- Debug help. Right now some additional stats file show up in cgroup
+	  if this option is enabled.
+
+CONFIG_CFQ_GROUP_IOSCHED
+	- Enables group scheduling in CFQ. Currently only 1 level of group
+	  creation is allowed.
 
 Details of cgroup files
 =======================
 - blkio.weight
-	- Specifies per cgroup weight.
-
+	- Specifies per cgroup weight. This is default weight of the group
+	  on all the devices until and unless overridden by per device rule.
+	  (See blkio.weight_device).
 	  Currently allowed range of weights is from 100 to 1000.
 
+- blkio.weight_device
+	- One can specify per cgroup per device rules using this interface.
+	  These rules override the default value of group weight as specified
+	  by blkio.weight.
+
+	  Following is the format.
+
+	  #echo dev_maj:dev_minor weight > /path/to/cgroup/blkio.weight_device
+	  Configure weight=300 on /dev/sdb (8:16) in this cgroup
+	  # echo 8:16 300 > blkio.weight_device
+	  # cat blkio.weight_device
+	  dev     weight
+	  8:16    300
+
+	  Configure weight=500 on /dev/sda (8:0) in this cgroup
+	  # echo 8:0 500 > blkio.weight_device
+	  # cat blkio.weight_device
+	  dev     weight
+	  8:0     500
+	  8:16    300
+
+	  Remove specific weight for /dev/sda in this cgroup
+	  # echo 8:0 0 > blkio.weight_device
+	  # cat blkio.weight_device
+	  dev     weight
+	  8:16    300
+
 - blkio.time
 	- disk time allocated to cgroup per device in milliseconds. First
 	  two fields specify the major and minor number of the device and
@@ -92,13 +115,105 @@ Details of cgroup files
 	  third field specifies the number of sectors transferred by the
 	  group to/from the device.
 
+- blkio.io_service_bytes
+	- Number of bytes transferred to/from the disk by the group. These
+	  are further divided by the type of operation - read or write, sync
+	  or async. First two fields specify the major and minor number of the
+	  device, third field specifies the operation type and the fourth field
+	  specifies the number of bytes.
+
+- blkio.io_serviced
+	- Number of IOs completed to/from the disk by the group. These
+	  are further divided by the type of operation - read or write, sync
+	  or async. First two fields specify the major and minor number of the
+	  device, third field specifies the operation type and the fourth field
+	  specifies the number of IOs.
+
+- blkio.io_service_time
+	- Total amount of time between request dispatch and request completion
+	  for the IOs done by this cgroup. This is in nanoseconds to make it
+	  meaningful for flash devices too. For devices with queue depth of 1,
+	  this time represents the actual service time. When queue_depth > 1,
+	  that is no longer true as requests may be served out of order. This
+	  may cause the service time for a given IO to include the service time
+	  of multiple IOs when served out of order which may result in total
+	  io_service_time > actual time elapsed. This time is further divided by
+	  the type of operation - read or write, sync or async. First two fields
+	  specify the major and minor number of the device, third field
+	  specifies the operation type and the fourth field specifies the
+	  io_service_time in ns.
+
+- blkio.io_wait_time
+	- Total amount of time the IOs for this cgroup spent waiting in the
+	  scheduler queues for service. This can be greater than the total time
+	  elapsed since it is cumulative io_wait_time for all IOs. It is not a
+	  measure of total time the cgroup spent waiting but rather a measure of
+	  the wait_time for its individual IOs. For devices with queue_depth > 1
+	  this metric does not include the time spent waiting for service once
+	  the IO is dispatched to the device but till it actually gets serviced
+	  (there might be a time lag here due to re-ordering of requests by the
+	  device). This is in nanoseconds to make it meaningful for flash
+	  devices too. This time is further divided by the type of operation -
+	  read or write, sync or async. First two fields specify the major and
+	  minor number of the device, third field specifies the operation type
+	  and the fourth field specifies the io_wait_time in ns.
+
+- blkio.io_merged
+	- Total number of bios/requests merged into requests belonging to this
+	  cgroup. This is further divided by the type of operation - read or
+	  write, sync or async.
+
+- blkio.io_queued
+	- Total number of requests queued up at any given instant for this
+	  cgroup. This is further divided by the type of operation - read or
+	  write, sync or async.
+
+- blkio.avg_queue_size
+	- Debugging aid only enabled if CONFIG_DEBUG_BLK_CGROUP=y.
+	  The average queue size for this cgroup over the entire time of this
+	  cgroup's existence. Queue size samples are taken each time one of the
+	  queues of this cgroup gets a timeslice.
+
+- blkio.group_wait_time
+	- Debugging aid only enabled if CONFIG_DEBUG_BLK_CGROUP=y.
+	  This is the amount of time the cgroup had to wait since it became busy
+	  (i.e., went from 0 to 1 request queued) to get a timeslice for one of
+	  its queues. This is different from the io_wait_time which is the
+	  cumulative total of the amount of time spent by each IO in that cgroup
+	  waiting in the scheduler queue. This is in nanoseconds. If this is
+	  read when the cgroup is in a waiting (for timeslice) state, the stat
+	  will only report the group_wait_time accumulated till the last time it
+	  got a timeslice and will not include the current delta.
+
+- blkio.empty_time
+	- Debugging aid only enabled if CONFIG_DEBUG_BLK_CGROUP=y.
+	  This is the amount of time a cgroup spends without any pending
+	  requests when not being served, i.e., it does not include any time
+	  spent idling for one of the queues of the cgroup. This is in
+	  nanoseconds. If this is read when the cgroup is in an empty state,
+	  the stat will only report the empty_time accumulated till the last
+	  time it had a pending request and will not include the current delta.
+
+- blkio.idle_time
+	- Debugging aid only enabled if CONFIG_DEBUG_BLK_CGROUP=y.
+	  This is the amount of time spent by the IO scheduler idling for a
+	  given cgroup in anticipation of a better request than the exising ones
+	  from other queues/cgroups. This is in nanoseconds. If this is read
+	  when the cgroup is in an idling state, the stat will only report the
+	  idle_time accumulated till the last idle period and will not include
+	  the current delta.
+
 - blkio.dequeue
-	- Debugging aid only enabled if CONFIG_DEBUG_CFQ_IOSCHED=y. This
+	- Debugging aid only enabled if CONFIG_DEBUG_BLK_CGROUP=y. This
 	  gives the statistics about how many a times a group was dequeued
 	  from service tree of the device. First two fields specify the major
 	  and minor number of the device and third field specifies the number
 	  of times a group was dequeued from a particular device.
 
+- blkio.reset_stats
+	- Writing an int to this file will result in resetting all the stats
+	  for that cgroup.
+
 CFQ sysfs tunable
 =================
 /sys/block/<disk>/queue/iosched/group_isolation

Documentation/cgroups/cgroups.txt

@@ -235,8 +235,7 @@ containing the following files describing that cgroup:
  - cgroup.procs: list of tgids in the cgroup.  This list is not
    guaranteed to be sorted or free of duplicate tgids, and userspace
    should sort/uniquify the list if this property is required.
-   Writing a tgid into this file moves all threads with that tgid into
-   this cgroup.
+   This is a read-only file, for now.
  - notify_on_release flag: run the release agent on exit?
  - release_agent: the path to use for release notifications (this file
    exists in the top cgroup only)
@@ -340,7 +339,7 @@ To mount a cgroup hierarchy with all available subsystems, type:
 The "xxx" is not interpreted by the cgroup code, but will appear in
 /proc/mounts so may be any useful identifying string that you like.
 
-To mount a cgroup hierarchy with just the cpuset and numtasks
+To mount a cgroup hierarchy with just the cpuset and memory
 subsystems, type:
 # mount -t cgroup -o cpuset,memory hier1 /dev/cgroup
 
@@ -573,7 +572,7 @@ void cancel_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
 
 Called when a task attach operation has failed after can_attach() has succeeded.
 A subsystem whose can_attach() has some side-effects should provide this
-function, so that the subsytem can implement a rollback. If not, not necessary.
+function, so that the subsystem can implement a rollback. If not, not necessary.
 This will be called only about subsystems whose can_attach() operation have
 succeeded.
 

Documentation/cgroups/cpusets.txt

@@ -42,7 +42,7 @@ Nodes to a set of tasks.   In this document "Memory Node" refers to
 an on-line node that contains memory.
 
 Cpusets constrain the CPU and Memory placement of tasks to only
-the resources within a tasks current cpuset.  They form a nested
+the resources within a task's current cpuset.  They form a nested
 hierarchy visible in a virtual file system.  These are the essential
 hooks, beyond what is already present, required to manage dynamic
 job placement on large systems.
@@ -53,11 +53,11 @@ Documentation/cgroups/cgroups.txt.
 Requests by a task, using the sched_setaffinity(2) system call to
 include CPUs in its CPU affinity mask, and using the mbind(2) and
 set_mempolicy(2) system calls to include Memory Nodes in its memory
-policy, are both filtered through that tasks cpuset, filtering out any
+policy, are both filtered through that task's cpuset, filtering out any
 CPUs or Memory Nodes not in that cpuset.  The scheduler will not
 schedule a task on a CPU that is not allowed in its cpus_allowed
 vector, and the kernel page allocator will not allocate a page on a
-node that is not allowed in the requesting tasks mems_allowed vector.
+node that is not allowed in the requesting task's mems_allowed vector.
 
 User level code may create and destroy cpusets by name in the cgroup
 virtual file system, manage the attributes and permissions of these
@@ -121,9 +121,9 @@ Cpusets extends these two mechanisms as follows:
  - Each task in the system is attached to a cpuset, via a pointer
    in the task structure to a reference counted cgroup structure.
  - Calls to sched_setaffinity are filtered to just those CPUs
-   allowed in that tasks cpuset.
+   allowed in that task's cpuset.
  - Calls to mbind and set_mempolicy are filtered to just
-   those Memory Nodes allowed in that tasks cpuset.
+   those Memory Nodes allowed in that task's cpuset.
  - The root cpuset contains all the systems CPUs and Memory
    Nodes.
  - For any cpuset, one can define child cpusets containing a subset
@@ -141,11 +141,11 @@ into the rest of the kernel, none in performance critical paths:
  - in init/main.c, to initialize the root cpuset at system boot.
  - in fork and exit, to attach and detach a task from its cpuset.
  - in sched_setaffinity, to mask the requested CPUs by what's
-   allowed in that tasks cpuset.
+   allowed in that task's cpuset.
  - in sched.c migrate_live_tasks(), to keep migrating tasks within
    the CPUs allowed by their cpuset, if possible.
  - in the mbind and set_mempolicy system calls, to mask the requested
-   Memory Nodes by what's allowed in that tasks cpuset.
+   Memory Nodes by what's allowed in that task's cpuset.
  - in page_alloc.c, to restrict memory to allowed nodes.
  - in vmscan.c, to restrict page recovery to the current cpuset.
 
@@ -155,7 +155,7 @@ 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 four added lines,
-displaying the tasks cpus_allowed (on which CPUs it may be scheduled)
+displaying the task's cpus_allowed (on which CPUs it may be scheduled)
 and mems_allowed (on which Memory Nodes it may obtain memory),
 in the two formats seen in the following example:
 
@@ -323,17 +323,17 @@ stack segment pages of a task.
 
 By default, both kinds of memory spreading are off, and memory
 pages are allocated on the node local to where the task is running,
-except perhaps as modified by the tasks NUMA mempolicy or cpuset
+except perhaps as modified by the task's NUMA mempolicy or cpuset
 configuration, so long as sufficient free memory pages are available.
 
 When new cpusets are created, they inherit the memory spread settings
 of their parent.
 
 Setting memory spreading causes allocations for the affected page
-or slab caches to ignore the tasks NUMA mempolicy and be spread
+or slab caches to ignore the task's NUMA mempolicy and be spread
 instead.    Tasks using mbind() or set_mempolicy() calls to set NUMA
 mempolicies will not notice any change in these calls as a result of
-their containing tasks memory spread settings.  If memory spreading
+their containing task's memory spread settings.  If memory spreading
 is turned off, then the currently specified NUMA mempolicy once again
 applies to memory page allocations.
 
@@ -357,7 +357,7 @@ pages from the node returned by cpuset_mem_spread_node().
 
 The cpuset_mem_spread_node() routine is also simple.  It uses the
 value of a per-task rotor cpuset_mem_spread_rotor to select the next
-node in the current tasks mems_allowed to prefer for the allocation.
+node in the current task's mems_allowed to prefer for the allocation.
 
 This memory placement policy is also known (in other contexts) as
 round-robin or interleave.
@@ -594,7 +594,7 @@ is attached, is subtle.
 If a cpuset has its Memory Nodes modified, then for each task attached
 to that cpuset, the next time that the kernel attempts to allocate
 a page of memory for that task, the kernel will notice the change
-in the tasks cpuset, and update its per-task memory placement to
+in the task's cpuset, and update its per-task memory placement to
 remain within the new cpusets memory placement.  If the task was using
 mempolicy MPOL_BIND, and the nodes to which it was bound overlap with
 its new cpuset, then the task will continue to use whatever subset
@@ -603,13 +603,13 @@ was using MPOL_BIND and now none of its MPOL_BIND nodes are allowed
 in the new cpuset, then the task will be essentially treated as if it
 was MPOL_BIND bound to the new cpuset (even though its NUMA placement,
 as queried by get_mempolicy(), doesn't change).  If a task is moved
-from one cpuset to another, then the kernel will adjust the tasks
+from one cpuset to another, then the kernel will adjust the task's
 memory placement, as above, the next time that the kernel attempts
 to allocate a page of memory for that task.
 
 If a cpuset has its 'cpuset.cpus' modified, then each task in that cpuset
 will have its allowed CPU placement changed immediately.  Similarly,
-if a tasks pid is written to another cpusets 'cpuset.tasks' file, then its
+if a task's pid is written to another cpusets 'cpuset.tasks' file, then its
 allowed CPU placement is changed immediately.  If such a task had been
 bound to some subset of its cpuset using the sched_setaffinity() call,
 the task will be allowed to run on any CPU allowed in its new cpuset,
@@ -626,16 +626,16 @@ cpusets memory placement policy 'cpuset.mems' subsequently changes.
 If the cpuset flag file 'cpuset.memory_migrate' is set true, then when
 tasks are attached to that cpuset, any pages that task had
 allocated to it on nodes in its previous cpuset are migrated
-to the tasks new cpuset. The relative placement of the page within
+to the task's new cpuset. The relative placement of the page within
 the cpuset is preserved during these migration operations if possible.
 For example if the page was on the second valid node of the prior cpuset
 then the page will be placed on the second valid node of the new cpuset.
 
-Also if 'cpuset.memory_migrate' is set true, then if that cpusets
+Also if 'cpuset.memory_migrate' is set true, then if that cpuset's
 'cpuset.mems' file is modified, pages allocated to tasks in that
 cpuset, that were on nodes in the previous setting of 'cpuset.mems',
 will be moved to nodes in the new setting of 'mems.'
-Pages that were not in the tasks prior cpuset, or in the cpusets
+Pages that were not in the task's prior cpuset, or in the cpuset's
 prior 'cpuset.mems' setting, will not be moved.
 
 There is an exception to the above.  If hotplug functionality is used
@@ -655,7 +655,7 @@ There is a second exception to the above.  GFP_ATOMIC requests are
 kernel internal allocations that must be satisfied, immediately.
 The kernel may drop some request, in rare cases even panic, if a
 GFP_ATOMIC alloc fails.  If the request cannot be satisfied within
-the current tasks cpuset, then we relax the cpuset, and look for
+the current task's cpuset, then we relax the cpuset, and look for
 memory anywhere we can find it.  It's better to violate the cpuset
 than stress the kernel.
 

Documentation/cgroups/memcg_test.txt

@@ -244,7 +244,7 @@ Under below explanation, we assume CONFIG_MEM_RES_CTRL_SWAP=y.
 	  we have to check if OLDPAGE/NEWPAGE is a valid page after commit().
 
 8. LRU
-        Each memcg has its own private LRU. Now, it's handling is under global
+        Each memcg has its own private LRU. Now, its handling is under global
 	VM's control (means that it's handled under global zone->lru_lock).
 	Almost all routines around memcg's LRU is called by global LRU's
 	list management functions under zone->lru_lock().

Documentation/cgroups/memory.txt

@@ -1,18 +1,15 @@
 Memory Resource Controller
 
 NOTE: The Memory Resource Controller has been generically been referred
-to as the memory controller in this document. Do not confuse memory controller
-used here with the memory controller that is used in hardware.
+      to as the memory controller in this document. Do not confuse memory
+      controller used here with the memory controller that is used in hardware.
 
-Salient features
-
-a. Enable control of Anonymous, Page Cache (mapped and unmapped) and
-   Swap Cache memory pages.
-b. The infrastructure allows easy addition of other types of memory to control
-c. Provides *zero overhead* for non memory controller users
-d. Provides a double LRU: global memory pressure causes reclaim from the
-   global LRU; a cgroup on hitting a limit, reclaims from the per
-   cgroup LRU
+(For editors)
+In this document:
+      When we mention a cgroup (cgroupfs's directory) with memory controller,
+      we call it "memory cgroup". When you see git-log and source code, you'll
+      see patch's title and function names tend to use "memcg".
+      In this document, we avoid using it.
 
 Benefits and Purpose of the memory controller
 
@@ -33,6 +30,45 @@ d. A CD/DVD burner could control the amount of memory used by the
 e. There are several other use cases, find one or use the controller just
    for fun (to learn and hack on the VM subsystem).
 
+Current Status: linux-2.6.34-mmotm(development version of 2010/April)
+
+Features:
+ - accounting anonymous pages, file caches, swap caches usage and limiting them.
+ - private LRU and reclaim routine. (system's global LRU and private LRU
+   work independently from each other)
+ - optionally, memory+swap usage can be accounted and limited.
+ - hierarchical accounting
+ - soft limit
+ - moving(recharging) account at moving a task is selectable.
+ - usage threshold notifier
+ - oom-killer disable knob and oom-notifier
+ - Root cgroup has no limit controls.
+
+ Kernel memory and Hugepages are not under control yet. We just manage
+ pages on LRU. To add more controls, we have to take care of performance.
+
+Brief summary of control files.
+
+ tasks				 # attach a task(thread) and show list of threads
+ cgroup.procs			 # show list of processes
+ cgroup.event_control		 # an interface for event_fd()
+ memory.usage_in_bytes		 # show current memory(RSS+Cache) usage.
+ memory.memsw.usage_in_bytes	 # show current memory+Swap usage
+ memory.limit_in_bytes		 # set/show limit of memory usage
+ memory.memsw.limit_in_bytes	 # set/show limit of memory+Swap usage
+ memory.failcnt			 # show the number of memory usage hits limits
+ memory.memsw.failcnt		 # show the number of memory+Swap hits limits
+ memory.max_usage_in_bytes	 # show max memory usage recorded
+ memory.memsw.usage_in_bytes	 # show max memory+Swap usage recorded
+ memory.soft_limit_in_bytes	 # set/show soft limit of memory usage
+ memory.stat			 # show various statistics
+ memory.use_hierarchy		 # set/show hierarchical account enabled
+ memory.force_empty		 # trigger forced move charge to parent
+ memory.swappiness		 # set/show swappiness parameter of vmscan
+				 (See sysctl's vm.swappiness)
+ memory.move_charge_at_immigrate # set/show controls of moving charges
+ memory.oom_control		 # set/show oom controls.
+
 1. History
 
 The memory controller has a long history. A request for comments for the memory
@@ -106,14 +142,14 @@ the necessary data structures and check if the cgroup that is being charged
 is over its limit. If it is then reclaim is invoked on the cgroup.
 More details can be found in the reclaim section of this document.
 If everything goes well, a page meta-data-structure called page_cgroup is
-allocated and associated with the page.  This routine also adds the page to
-the per cgroup LRU.
+updated. page_cgroup has its own LRU on cgroup.
+(*) page_cgroup structure is allocated at boot/memory-hotplug time.
 
 2.2.1 Accounting details
 
 All mapped anon pages (RSS) and cache pages (Page Cache) are accounted.
-(some pages which never be reclaimable and will not be on global LRU
- are not accounted. we just accounts pages under usual vm management.)
+Some pages which are never reclaimable and will not be on the global LRU
+are not accounted. We just account pages under usual VM management.
 
 RSS pages are accounted at page_fault unless they've already been accounted
 for earlier. A file page will be accounted for as Page Cache when it's
@@ -121,12 +157,19 @@ inserted into inode (radix-tree). While it's mapped into the page tables of
 processes, duplicate accounting is carefully avoided.
 
 A RSS page is unaccounted when it's fully unmapped. A PageCache page is
-unaccounted when it's removed from radix-tree.
+unaccounted when it's removed from radix-tree. Even if RSS pages are fully
+unmapped (by kswapd), they may exist as SwapCache in the system until they
+are really freed. Such SwapCaches also also accounted.
+A swapped-in page is not accounted until it's mapped.
+
+Note: The kernel does swapin-readahead and read multiple swaps at once.
+This means swapped-in pages may contain pages for other tasks than a task
+causing page fault. So, we avoid accounting at swap-in I/O.
 
 At page migration, accounting information is kept.
 
-Note: we just account pages-on-lru because our purpose is to control amount
-of used pages. not-on-lru pages are tend to be out-of-control from vm view.
+Note: we just account pages-on-LRU because our purpose is to control amount
+of used pages; not-on-LRU pages tend to be out-of-control from VM view.
 
 2.3 Shared Page Accounting
 
@@ -143,6 +186,7 @@ caller of swapoff rather than the users of shmem.
 
 
 2.4 Swap Extension (CONFIG_CGROUP_MEM_RES_CTLR_SWAP)
+
 Swap Extension allows you to record charge for swap. A swapped-in page is
 charged back to original page allocator if possible.
 
@@ -150,13 +194,20 @@ When swap is accounted, following files are added.
  - memory.memsw.usage_in_bytes.
  - memory.memsw.limit_in_bytes.
 
-usage of mem+swap is limited by memsw.limit_in_bytes.
+memsw means memory+swap. Usage of memory+swap is limited by
+memsw.limit_in_bytes.
 
-* why 'mem+swap' rather than swap.
+Example: Assume a system with 4G of swap. A task which allocates 6G of memory
+(by mistake) under 2G memory limitation will use all swap.
+In this case, setting memsw.limit_in_bytes=3G will prevent bad use of swap.
+By using memsw limit, you can avoid system OOM which can be caused by swap
+shortage.
+
+* why 'memory+swap' rather than swap.
 The global LRU(kswapd) can swap out arbitrary pages. Swap-out means
 to move account from memory to swap...there is no change in usage of
-mem+swap. In other words, when we want to limit the usage of swap without
-affecting global LRU, mem+swap limit is better than just limiting swap from
+memory+swap. In other words, when we want to limit the usage of swap without
+affecting global LRU, memory+swap limit is better than just limiting swap from
 OS point of view.
 
 * What happens when a cgroup hits memory.memsw.limit_in_bytes
@@ -168,12 +219,12 @@ it by cgroup.
 
 2.5 Reclaim
 
-Each cgroup maintains a per cgroup LRU that consists of an active
-and inactive list. When a cgroup goes over its limit, we first try
+Each cgroup maintains a per cgroup LRU which has the same structure as
+global VM. When a cgroup goes over its limit, we first try
 to reclaim memory from the cgroup so as to make space for the new
 pages that the cgroup has touched. If the reclaim is unsuccessful,
 an OOM routine is invoked to select and kill the bulkiest task in the
-cgroup.
+cgroup. (See 10. OOM Control below.)
 
 The reclaim algorithm has not been modified for cgroups, except that
 pages that are selected for reclaiming come from the per cgroup LRU
@@ -184,13 +235,22 @@ limits on the root cgroup.
 
 Note2: When panic_on_oom is set to "2", the whole system will panic.
 
-2. Locking
+When oom event notifier is registered, event will be delivered.
+(See oom_control section)
+
+2.6 Locking
 
-The memory controller uses the following hierarchy
+   lock_page_cgroup()/unlock_page_cgroup() should not be called under
+   mapping->tree_lock.
 
-1. zone->lru_lock is used for selecting pages to be isolated
-2. mem->per_zone->lru_lock protects the per cgroup LRU (per zone)
-3. lock_page_cgroup() is used to protect page->page_cgroup
+   Other lock order is following:
+   PG_locked.
+   mm->page_table_lock
+       zone->lru_lock
+	  lock_page_cgroup.
+  In many cases, just lock_page_cgroup() is called.
+  per-zone-per-cgroup LRU (cgroup's private LRU) is just guarded by
+  zone->lru_lock, it has no lock of its own.
 
 3. User Interface
 
@@ -199,6 +259,7 @@ The memory controller uses the following hierarchy
 a. Enable CONFIG_CGROUPS
 b. Enable CONFIG_RESOURCE_COUNTERS
 c. Enable CONFIG_CGROUP_MEM_RES_CTLR
+d. Enable CONFIG_CGROUP_MEM_RES_CTLR_SWAP (to use swap extension)
 
 1. Prepare the cgroups
 # mkdir -p /cgroups
@@ -206,31 +267,28 @@ c. Enable CONFIG_CGROUP_MEM_RES_CTLR
 
 2. Make the new group and move bash into it
 # mkdir /cgroups/0
-# echo $$ >  /cgroups/0/tasks
+# echo $$ > /cgroups/0/tasks
 
-Since now we're in the 0 cgroup,
-We can alter the memory limit:
+Since now we're in the 0 cgroup, we can alter the memory limit:
 # echo 4M > /cgroups/0/memory.limit_in_bytes
 
 NOTE: We can use a suffix (k, K, m, M, g or G) to indicate values in kilo,
-mega or gigabytes.
+mega or gigabytes. (Here, Kilo, Mega, Giga are Kibibytes, Mebibytes, Gibibytes.)
+
 NOTE: We can write "-1" to reset the *.limit_in_bytes(unlimited).
 NOTE: We cannot set limits on the root cgroup any more.
 
 # cat /cgroups/0/memory.limit_in_bytes
 4194304
 
-NOTE: The interface has now changed to display the usage in bytes
-instead of pages
-
 We can check the usage:
 # cat /cgroups/0/memory.usage_in_bytes
 1216512
 
 A successful write to this file does not guarantee a successful set of
-this limit to the value written into the file.  This can be due to a
+this limit to the value written into the file. This can be due to a
 number of factors, such as rounding up to page boundaries or the total
-availability of memory on the system.  The user is required to re-read
+availability of memory on the system. The user is required to re-read
 this file after a write to guarantee the value committed by the kernel.
 
 # echo 1 > memory.limit_in_bytes
@@ -245,15 +303,23 @@ caches, RSS and Active pages/Inactive pages are shown.
 
 4. Testing
 
-Balbir posted lmbench, AIM9, LTP and vmmstress results [10] and [11].
-Apart from that v6 has been tested with several applications and regular
-daily use. The controller has also been tested on the PPC64, x86_64 and
-UML platforms.
+For testing features and implementation, see memcg_test.txt.
+
+Performance test is also important. To see pure memory controller's overhead,
+testing on tmpfs will give you good numbers of small overheads.
+Example: do kernel make on tmpfs.
+
+Page-fault scalability is also important. At measuring parallel
+page fault test, multi-process test may be better than multi-thread
+test because it has noise of shared objects/status.
+
+But the above two are testing extreme situations.
+Trying usual test under memory controller is always helpful.
 
 4.1 Troubleshooting
 
 Sometimes a user might find that the application under a cgroup is
-terminated. There are several causes for this:
+terminated by OOM killer. There are several causes for this:
 
 1. The cgroup limit is too low (just too low to do anything useful)
 2. The user is using anonymous memory and swap is turned off or too low
@@ -261,23 +327,29 @@ terminated. There are several causes for this:
 A sync followed by echo 1 > /proc/sys/vm/drop_caches will help get rid of
 some of the pages cached in the cgroup (page cache pages).
 
+To know what happens, disable OOM_Kill by 10. OOM Control(see below) and
+seeing what happens will be helpful.
+
 4.2 Task migration
 
-When a task migrates from one cgroup to another, it's charge is not
+When a task migrates from one cgroup to another, its charge is not
 carried forward by default. The pages allocated from the original cgroup still
 remain charged to it, the charge is dropped when the page is freed or
 reclaimed.
 
-Note: You can move charges of a task along with task migration. See 8.
+You can move charges of a task along with task migration.
+See 8. "Move charges at task migration"
 
 4.3 Removing a cgroup
 
 A cgroup can be removed by rmdir, but as discussed in sections 4.1 and 4.2, a
 cgroup might have some charge associated with it, even though all
-tasks have migrated away from it.
-Such charges are freed(at default) or moved to its parent. When moved,
-both of RSS and CACHES are moved to parent.
-If both of them are busy, rmdir() returns -EBUSY. See 5.1 Also.
+tasks have migrated away from it. (because we charge against pages, not
+against tasks.)
+
+Such charges are freed or moved to their parent. At moving, both of RSS
+and CACHES are moved to parent.
+rmdir() may return -EBUSY if freeing/moving fails. See 5.1 also.
 
 Charges recorded in swap information is not updated at removal of cgroup.
 Recorded information is discarded and a cgroup which uses swap (swapcache)
@@ -293,10 +365,10 @@ will be charged as a new owner of it.
 
   # echo 0 > memory.force_empty
 
-  Almost all pages tracked by this memcg will be unmapped and freed. Some of
-  pages cannot be freed because it's locked or in-use. Such pages are moved
-  to parent and this cgroup will be empty. But this may return -EBUSY in
-  some too busy case.
+  Almost all pages tracked by this memory cgroup will be unmapped and freed.
+  Some pages cannot be freed because they are locked or in-use. Such pages are
+  moved to parent and this cgroup will be empty. This may return -EBUSY if
+  VM is too busy to free/move all pages immediately.
 
   Typical use case of this interface is that calling this before rmdir().
   Because rmdir() moves all pages to parent, some out-of-use page caches can be
@@ -306,19 +378,41 @@ will be charged as a new owner of it.
 
 memory.stat file includes following statistics
 
+# per-memory cgroup local status
 cache		- # of bytes of page cache memory.
 rss		- # of bytes of anonymous and swap cache memory.
+mapped_file	- # of bytes of mapped file (includes tmpfs/shmem)
 pgpgin		- # of pages paged in (equivalent to # of charging events).
 pgpgout		- # of pages paged out (equivalent to # of uncharging events).
-active_anon	- # of bytes of anonymous and  swap cache memory on active
-		  lru list.
+swap		- # of bytes of swap usage
 inactive_anon	- # of bytes of anonymous memory and swap cache memory on
-		  inactive lru list.
-active_file	- # of bytes of file-backed memory on active lru list.
-inactive_file	- # of bytes of file-backed memory on inactive lru list.
+		LRU list.
+active_anon	- # of bytes of anonymous and swap cache memory on active
+		inactive LRU list.
+inactive_file	- # of bytes of file-backed memory on inactive LRU list.
+active_file	- # of bytes of file-backed memory on active LRU list.
 unevictable	- # of bytes of memory that cannot be reclaimed (mlocked etc).
 
-The following additional stats are dependent on CONFIG_DEBUG_VM.
+# status considering hierarchy (see memory.use_hierarchy settings)
+
+hierarchical_memory_limit - # of bytes of memory limit with regard to hierarchy
+			under which the memory cgroup is
+hierarchical_memsw_limit - # of bytes of memory+swap limit with regard to
+			hierarchy under which memory cgroup is.
+
+total_cache		- sum of all children's "cache"
+total_rss		- sum of all children's "rss"
+total_mapped_file	- sum of all children's "cache"
+total_pgpgin		- sum of all children's "pgpgin"
+total_pgpgout		- sum of all children's "pgpgout"
+total_swap		- sum of all children's "swap"
+total_inactive_anon	- sum of all children's "inactive_anon"
+total_active_anon	- sum of all children's "active_anon"
+total_inactive_file	- sum of all children's "inactive_file"
+total_active_file	- sum of all children's "active_file"
+total_unevictable	- sum of all children's "unevictable"
+
+# The following additional stats are dependent on CONFIG_DEBUG_VM.
 
 inactive_ratio		- VM internal parameter. (see mm/page_alloc.c)
 recent_rotated_anon	- VM internal parameter. (see mm/vmscan.c)
@@ -327,24 +421,37 @@ recent_scanned_anon	- VM internal parameter. (see mm/vmscan.c)
 recent_scanned_file	- VM internal parameter. (see mm/vmscan.c)
 
 Memo:
-	recent_rotated means recent frequency of lru rotation.
-	recent_scanned means recent # of scans to lru.
+	recent_rotated means recent frequency of LRU rotation.
+	recent_scanned means recent # of scans to LRU.
 	showing for better debug please see the code for meanings.
 
 Note:
 	Only anonymous and swap cache memory is listed as part of 'rss' stat.
 	This should not be confused with the true 'resident set size' or the
-	amount of physical memory used by the cgroup. Per-cgroup rss
-	accounting is not done yet.
+	amount of physical memory used by the cgroup.
+	'rss + file_mapped" will give you resident set size of cgroup.
+	(Note: file and shmem may be shared among other cgroups. In that case,
+	 file_mapped is accounted only when the memory cgroup is owner of page
+	 cache.)
 
 5.3 swappiness
-  Similar to /proc/sys/vm/swappiness, but affecting a hierarchy of groups only.
 
-  Following cgroups' swapiness can't be changed.
-  - root cgroup (uses /proc/sys/vm/swappiness).
-  - a cgroup which uses hierarchy and it has child cgroup.
-  - a cgroup which uses hierarchy and not the root of hierarchy.
+Similar to /proc/sys/vm/swappiness, but affecting a hierarchy of groups only.
 
+Following cgroups' swappiness can't be changed.
+- root cgroup (uses /proc/sys/vm/swappiness).
+- a cgroup which uses hierarchy and it has other cgroup(s) below it.
+- a cgroup which uses hierarchy and not the root of hierarchy.
+
+5.4 failcnt
+
+A memory cgroup provides memory.failcnt and memory.memsw.failcnt files.
+This failcnt(== failure count) shows the number of times that a usage counter
+hit its limit. When a memory cgroup hits a limit, failcnt increases and
+memory under it will be reclaimed.
+
+You can reset failcnt by writing 0 to failcnt file.
+# echo 0 > .../memory.failcnt
 
 6. Hierarchy support
 
@@ -363,13 +470,13 @@ hierarchy
 
 In the diagram above, with hierarchical accounting enabled, all memory
 usage of e, is accounted to its ancestors up until the root (i.e, c and root),
-that has memory.use_hierarchy enabled.  If one of the ancestors goes over its
+that has memory.use_hierarchy enabled. If one of the ancestors goes over its
 limit, the reclaim algorithm reclaims from the tasks in the ancestor and the
 children of the ancestor.
 
 6.1 Enabling hierarchical accounting and reclaim
 
-The memory controller by default disables the hierarchy feature. Support
+A memory cgroup by default disables the hierarchy feature. Support
 can be enabled by writing 1 to memory.use_hierarchy file of the root cgroup
 
 # echo 1 > memory.use_hierarchy
@@ -379,10 +486,10 @@ The feature can be disabled by
 # echo 0 > memory.use_hierarchy
 
 NOTE1: Enabling/disabling will fail if the cgroup already has other
-cgroups created below it.
+       cgroups created below it.
 
 NOTE2: When panic_on_oom is set to "2", the whole system will panic in
-case of an oom event in any cgroup.
+       case of an OOM event in any cgroup.
 
 7. Soft limits
 
@@ -392,7 +499,7 @@ is to allow control groups to use as much of the memory as needed, provided
 a. There is no memory contention
 b. They do not exceed their hard limit
 
-When the system detects memory contention or low memory control groups
+When the system detects memory contention or low memory, control groups
 are pushed back to their soft limits. If the soft limit of each control
 group is very high, they are pushed back as much as possible to make
 sure that one control group does not starve the others of memory.
@@ -406,7 +513,7 @@ it gets invoked from balance_pgdat (kswapd).
 7.1 Interface
 
 Soft limits can be setup by using the following commands (in this example we
-assume a soft limit of 256 megabytes)
+assume a soft limit of 256 MiB)
 
 # echo 256M > memory.soft_limit_in_bytes
 
@@ -442,7 +549,7 @@ Note: Charges are moved only when you move mm->owner, IOW, a leader of a thread
 Note: If we cannot find enough space for the task in the destination cgroup, we
       try to make space by reclaiming memory. Task migration may fail if we
       cannot make enough space.
-Note: It can take several seconds if you move charges in giga bytes order.
+Note: It can take several seconds if you move charges much.
 
 And if you want disable it again:
 
@@ -451,21 +558,27 @@ And if you want disable it again:
 8.2 Type of charges which can be move
 
 Each bits of move_charge_at_immigrate has its own meaning about what type of
-charges should be moved.
+charges should be moved. But in any cases, it must be noted that an account of
+a page or a swap can be moved only when it is charged to the task's current(old)
+memory cgroup.
 
   bit | what type of charges would be moved ?
  -----+------------------------------------------------------------------------
    0  | A charge of an anonymous page(or swap of it) used by the target task.
       | Those pages and swaps must be used only by the target task. You must
       | enable Swap Extension(see 2.4) to enable move of swap charges.
-
-Note: Those pages and swaps must be charged to the old cgroup.
-Note: More type of pages(e.g. file cache, shmem,) will be supported by other
-      bits in future.
+ -----+------------------------------------------------------------------------
+   1  | A charge of file pages(normal file, tmpfs file(e.g. ipc shared memory)
+      | and swaps of tmpfs file) mmapped by the target task. Unlike the case of
+      | anonymous pages, file pages(and swaps) in the range mmapped by the task
+      | will be moved even if the task hasn't done page fault, i.e. they might
+      | not be the task's "RSS", but other task's "RSS" that maps the same file.
+      | And mapcount of the page is ignored(the page can be moved even if
+      | page_mapcount(page) > 1). You must enable Swap Extension(see 2.4) to
+      | enable move of swap charges.
 
 8.3 TODO
 
-- Add support for other types of pages(e.g. file cache, shmem, etc.).
 - Implement madvise(2) to let users decide the vma to be moved or not to be
   moved.
 - All of moving charge operations are done under cgroup_mutex. It's not good
@@ -473,22 +586,61 @@ Note: More type of pages(e.g. file cache, shmem,) will be supported by other
 
 9. Memory thresholds
 
-Memory controler implements memory thresholds using cgroups notification
+Memory cgroup implements memory thresholds using cgroups notification
 API (see cgroups.txt). It allows to register multiple memory and memsw
 thresholds and gets notifications when it crosses.
 
 To register a threshold application need:
- - create an eventfd using eventfd(2);
- - open memory.usage_in_bytes or memory.memsw.usage_in_bytes;
- - write string like "<event_fd> <memory.usage_in_bytes> <threshold>" to
-   cgroup.event_control.
+- create an eventfd using eventfd(2);
+- open memory.usage_in_bytes or memory.memsw.usage_in_bytes;
+- write string like "<event_fd> <fd of memory.usage_in_bytes> <threshold>" to
+  cgroup.event_control.
 
 Application will be notified through eventfd when memory usage crosses
 threshold in any direction.
 
 It's applicable for root and non-root cgroup.
 
-10. TODO
+10. OOM Control
+
+memory.oom_control file is for OOM notification and other controls.
+
+Memory cgroup implements OOM notifier using cgroup notification
+API (See cgroups.txt). It allows to register multiple OOM notification
+delivery and gets notification when OOM happens.
+
+To register a notifier, application need:
+ - create an eventfd using eventfd(2)
+ - open memory.oom_control file
+ - write string like "<event_fd> <fd of memory.oom_control>" to
+   cgroup.event_control
+
+Application will be notified through eventfd when OOM happens.
+OOM notification doesn't work for root cgroup.
+
+You can disable OOM-killer by writing "1" to memory.oom_control file, as:
+
+	#echo 1 > memory.oom_control
+
+This operation is only allowed to the top cgroup of sub-hierarchy.
+If OOM-killer is disabled, tasks under cgroup will hang/sleep
+in memory cgroup's OOM-waitqueue when they request accountable memory.
+
+For running them, you have to relax the memory cgroup's OOM status by
+	* enlarge limit or reduce usage.
+To reduce usage,
+	* kill some tasks.
+	* move some tasks to other group with account migration.
+	* remove some files (on tmpfs?)
+
+Then, stopped tasks will work again.
+
+At reading, current status of OOM is shown.
+	oom_kill_disable 0 or 1 (if 1, oom-killer is disabled)
+	under_oom	 0 or 1 (if 1, the memory cgroup is under OOM, tasks may
+				 be stopped.)
+
+11. TODO
 
 1. Add support for accounting huge pages (as a separate controller)
 2. Make per-cgroup scanner reclaim not-shared pages first

Documentation/circular-buffers.txt

@@ -0,0 +1,234 @@
+			       ================
+			       CIRCULAR BUFFERS
+			       ================
+
+By: David Howells <dhowells@redhat.com>
+    Paul E. McKenney <paulmck@linux.vnet.ibm.com>
+
+
+Linux provides a number of features that can be used to implement circular
+buffering.  There are two sets of such features:
+
+ (1) Convenience functions for determining information about power-of-2 sized
+     buffers.
+
+ (2) Memory barriers for when the producer and the consumer of objects in the
+     buffer don't want to share a lock.
+
+To use these facilities, as discussed below, there needs to be just one
+producer and just one consumer.  It is possible to handle multiple producers by
+serialising them, and to handle multiple consumers by serialising them.
+
+
+Contents:
+
+ (*) What is a circular buffer?
+
+ (*) Measuring power-of-2 buffers.
+
+ (*) Using memory barriers with circular buffers.
+     - The producer.
+     - The consumer.
+
+
+==========================
+WHAT IS A CIRCULAR BUFFER?
+==========================
+
+First of all, what is a circular buffer?  A circular buffer is a buffer of
+fixed, finite size into which there are two indices:
+
+ (1) A 'head' index - the point at which the producer inserts items into the
+     buffer.
+
+ (2) A 'tail' index - the point at which the consumer finds the next item in
+     the buffer.
+
+Typically when the tail pointer is equal to the head pointer, the buffer is
+empty; and the buffer is full when the head pointer is one less than the tail
+pointer.
+
+The head index is incremented when items are added, and the tail index when
+items are removed.  The tail index should never jump the head index, and both
+indices should be wrapped to 0 when they reach the end of the buffer, thus
+allowing an infinite amount of data to flow through the buffer.
+
+Typically, items will all be of the same unit size, but this isn't strictly
+required to use the techniques below.  The indices can be increased by more
+than 1 if multiple items or variable-sized items are to be included in the
+buffer, provided that neither index overtakes the other.  The implementer must
+be careful, however, as a region more than one unit in size may wrap the end of
+the buffer and be broken into two segments.
+
+
+============================
+MEASURING POWER-OF-2 BUFFERS
+============================
+
+Calculation of the occupancy or the remaining capacity of an arbitrarily sized
+circular buffer would normally be a slow operation, requiring the use of a
+modulus (divide) instruction.  However, if the buffer is of a power-of-2 size,
+then a much quicker bitwise-AND instruction can be used instead.
+
+Linux provides a set of macros for handling power-of-2 circular buffers.  These
+can be made use of by:
+
+	#include <linux/circ_buf.h>
+
+The macros are:
+
+ (*) Measure the remaining capacity of a buffer:
+
+	CIRC_SPACE(head_index, tail_index, buffer_size);
+
+     This returns the amount of space left in the buffer[1] into which items
+     can be inserted.
+
+
+ (*) Measure the maximum consecutive immediate space in a buffer:
+
+	CIRC_SPACE_TO_END(head_index, tail_index, buffer_size);
+
+     This returns the amount of consecutive space left in the buffer[1] into
+     which items can be immediately inserted without having to wrap back to the
+     beginning of the buffer.
+
+
+ (*) Measure the occupancy of a buffer:
+
+	CIRC_CNT(head_index, tail_index, buffer_size);
+
+     This returns the number of items currently occupying a buffer[2].
+
+
+ (*) Measure the non-wrapping occupancy of a buffer:
+
+	CIRC_CNT_TO_END(head_index, tail_index, buffer_size);
+
+     This returns the number of consecutive items[2] that can be extracted from
+     the buffer without having to wrap back to the beginning of the buffer.
+
+
+Each of these macros will nominally return a value between 0 and buffer_size-1,
+however:
+
+ [1] CIRC_SPACE*() are intended to be used in the producer.  To the producer
+     they will return a lower bound as the producer controls the head index,
+     but the consumer may still be depleting the buffer on another CPU and
+     moving the tail index.
+
+     To the consumer it will show an upper bound as the producer may be busy
+     depleting the space.
+
+ [2] CIRC_CNT*() are intended to be used in the consumer.  To the consumer they
+     will return a lower bound as the consumer controls the tail index, but the
+     producer may still be filling the buffer on another CPU and moving the
+     head index.
+
+     To the producer it will show an upper bound as the consumer may be busy
+     emptying the buffer.
+
+ [3] To a third party, the order in which the writes to the indices by the
+     producer and consumer become visible cannot be guaranteed as they are
+     independent and may be made on different CPUs - so the result in such a
+     situation will merely be a guess, and may even be negative.
+
+
+===========================================
+USING MEMORY BARRIERS WITH CIRCULAR BUFFERS
+===========================================
+
+By using memory barriers in conjunction with circular buffers, you can avoid
+the need to:
+
+ (1) use a single lock to govern access to both ends of the buffer, thus
+     allowing the buffer to be filled and emptied at the same time; and
+
+ (2) use atomic counter operations.
+
+There are two sides to this: the producer that fills the buffer, and the
+consumer that empties it.  Only one thing should be filling a buffer at any one
+time, and only one thing should be emptying a buffer at any one time, but the
+two sides can operate simultaneously.
+
+
+THE PRODUCER
+------------
+
+The producer will look something like this:
+
+	spin_lock(&producer_lock);
+
+	unsigned long head = buffer->head;
+	unsigned long tail = ACCESS_ONCE(buffer->tail);
+
+	if (CIRC_SPACE(head, tail, buffer->size) >= 1) {
+		/* insert one item into the buffer */
+		struct item *item = buffer[head];
+
+		produce_item(item);
+
+		smp_wmb(); /* commit the item before incrementing the head */
+
+		buffer->head = (head + 1) & (buffer->size - 1);
+
+		/* wake_up() will make sure that the head is committed before
+		 * waking anyone up */
+		wake_up(consumer);
+	}
+
+	spin_unlock(&producer_lock);
+
+This will instruct the CPU that the contents of the new item must be written
+before the head index makes it available to the consumer and then instructs the
+CPU that the revised head index must be written before the consumer is woken.
+
+Note that wake_up() doesn't have to be the exact mechanism used, but whatever
+is used must guarantee a (write) memory barrier between the update of the head
+index and the change of state of the consumer, if a change of state occurs.
+
+
+THE CONSUMER
+------------
+
+The consumer will look something like this:
+
+	spin_lock(&consumer_lock);
+
+	unsigned long head = ACCESS_ONCE(buffer->head);
+	unsigned long tail = buffer->tail;
+
+	if (CIRC_CNT(head, tail, buffer->size) >= 1) {
+		/* read index before reading contents at that index */
+		smp_read_barrier_depends();
+
+		/* extract one item from the buffer */
+		struct item *item = buffer[tail];
+
+		consume_item(item);
+
+		smp_mb(); /* finish reading descriptor before incrementing tail */
+
+		buffer->tail = (tail + 1) & (buffer->size - 1);
+	}
+
+	spin_unlock(&consumer_lock);
+
+This will instruct the CPU to make sure the index is up to date before reading
+the new item, and then it shall make sure the CPU has finished reading the item
+before it writes the new tail pointer, which will erase the item.
+
+
+Note the use of ACCESS_ONCE() in both algorithms to read the opposition index.
+This prevents the compiler from discarding and reloading its cached value -
+which some compilers will do across smp_read_barrier_depends().  This isn't
+strictly needed if you can be sure that the opposition index will _only_ be
+used the once.
+
+
+===============
+FURTHER READING
+===============
+
+See also Documentation/memory-barriers.txt for a description of Linux's memory
+barrier facilities.

Documentation/connector/cn_test.c

@@ -25,6 +25,7 @@
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/skbuff.h>
+#include <linux/slab.h>
 #include <linux/timer.h>
 
 #include <linux/connector.h>

Documentation/connector/connector.txt

@@ -88,7 +88,7 @@ int cn_netlink_send(struct cn_msg *msg, u32 __groups, int gfp_mask);
  int gfp_mask			- GFP mask.
 
  Note: When registering new callback user, connector core assigns
- netlink group to the user which is equal to it's id.idx.
+ netlink group to the user which is equal to its id.idx.
 
 /*****************************************/
 Protocol description.

Documentation/credentials.txt

@@ -408,9 +408,6 @@ This should be used inside the RCU read lock, as in the following example:
 		...
 	}
 
-A function need not get RCU read lock to use __task_cred() if it is holding a
-spinlock at the time as this implicitly holds the RCU read lock.
-
 Should it be necessary to hold another task's credentials for a long period of
 time, and possibly to sleep whilst doing so, then the caller should get a
 reference on them using:
@@ -426,17 +423,16 @@ credentials, hiding the RCU magic from the caller:
 	uid_t task_uid(task)		Task's real UID
 	uid_t task_euid(task)		Task's effective UID
 
-If the caller is holding a spinlock or the RCU read lock at the time anyway,
-then:
+If the caller is holding the RCU read lock at the time anyway, then:
 
 	__task_cred(task)->uid
 	__task_cred(task)->euid
 
 should be used instead.  Similarly, if multiple aspects of a task's credentials
-need to be accessed, RCU read lock or a spinlock should be used, __task_cred()
-called, the result stored in a temporary pointer and then the credential
-aspects called from that before dropping the lock.  This prevents the
-potentially expensive RCU magic from being invoked multiple times.
+need to be accessed, RCU read lock should be used, __task_cred() called, the
+result stored in a temporary pointer and then the credential aspects called
+from that before dropping the lock.  This prevents the potentially expensive
+RCU magic from being invoked multiple times.
 
 Should some other single aspect of another task's credentials need to be
 accessed, then this can be used:

Documentation/development-process/2.Process

@@ -151,7 +151,7 @@ The stages that a patch goes through are, generally:
    well.
 
  - Wider review.  When the patch is getting close to ready for mainline
-   inclusion, it will be accepted by a relevant subsystem maintainer -
+   inclusion, it should be accepted by a relevant subsystem maintainer -
    though this acceptance is not a guarantee that the patch will make it
    all the way to the mainline.  The patch will show up in the maintainer's
    subsystem tree and into the staging trees (described below).  When the
@@ -159,6 +159,15 @@ The stages that a patch goes through are, generally:
    the discovery of any problems resulting from the integration of this
    patch with work being done by others.
 
+-  Please note that most maintainers also have day jobs, so merging
+   your patch may not be their highest priority.  If your patch is
+   getting feedback about changes that are needed, you should either
+   make those changes or justify why they should not be made.  If your
+   patch has no review complaints but is not being merged by its
+   appropriate subsystem or driver maintainer, you should be persistent
+   in updating the patch to the current kernel so that it applies cleanly
+   and keep sending it for review and merging.
+
  - Merging into the mainline.  Eventually, a successful patch will be
    merged into the mainline repository managed by Linus Torvalds.  More
    comments and/or problems may surface at this time; it is important that
@@ -258,12 +267,8 @@ an appropriate subsystem tree or be sent directly to Linus.  In a typical
 development cycle, approximately 10% of the patches going into the mainline
 get there via -mm.
 
-The current -mm patch can always be found from the front page of
-
-	http://kernel.org/
-
-Those who want to see the current state of -mm can get the "-mm of the
-moment" tree, found at:
+The current -mm patch is available in the "mmotm" (-mm of the moment)
+directory at:
 
 	http://userweb.kernel.org/~akpm/mmotm/
 
@@ -298,6 +303,12 @@ volatility of linux-next tends to make it a difficult development target.
 See http://lwn.net/Articles/289013/ for more information on this topic, and
 stay tuned; much is still in flux where linux-next is involved.
 
+Besides the mmotm and linux-next trees, the kernel source tree now contains
+the drivers/staging/ directory and many sub-directories for drivers or
+filesystems that are on their way to being added to the kernel tree
+proper, but they remain in drivers/staging/ while they still need more
+work.
+
 
 2.5: TOOLS
 
@@ -319,9 +330,9 @@ developers; even if they do not use it for their own work, they'll need git
 to keep up with what other developers (and the mainline) are doing.
 
 Git is now packaged by almost all Linux distributions.  There is a home
-page at 
+page at:
 
-	http://git.or.cz/
+	http://git-scm.com/
 
 That page has pointers to documentation and tutorials.  One should be
 aware, in particular, of the Kernel Hacker's Guide to git, which has

Documentation/development-process/7.AdvancedTopics

@@ -25,7 +25,7 @@ long document in its own right.  Instead, the focus here will be on how git
 fits into the kernel development process in particular.  Developers who
 wish to come up to speed with git will find more information at:
 
-	http://git.or.cz/
+	http://git-scm.com/
 
 	http://www.kernel.org/pub/software/scm/git/docs/user-manual.html
 

Documentation/devices.txt

@@ -443,6 +443,8 @@ Your cooperation is appreciated.
 		231 = /dev/snapshot	System memory snapshot device
 		232 = /dev/kvm		Kernel-based virtual machine (hardware virtualization extensions)
 		233 = /dev/kmview	View-OS A process with a view
+		234 = /dev/btrfs-control	Btrfs control device
+		235 = /dev/autofs	Autofs control device
 		240-254			Reserved for local use
 		255			Reserved for MISC_DYNAMIC_MINOR
 

Documentation/dvb/ci.txt

@@ -41,7 +41,7 @@ This application requires the following to function properly as of now.
 
 * Cards that fall in this category
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-At present the cards that fall in this category are the Twinhan and it's
+At present the cards that fall in this category are the Twinhan and its
 clones, these cards are available as VVMER, Tomato, Hercules, Orange and
 so on.
 

Documentation/dvb/contributors.txt

@@ -1,7 +1,7 @@
 Thanks go to the following people for patches and contributions:
 
 Michael Hunold <m.hunold@gmx.de>
-  for the initial saa7146 driver and it's recent overhaul
+  for the initial saa7146 driver and its recent overhaul
 
 Christian Theiss
   for his work on the initial Linux DVB driver

Documentation/fb/efifb.txt

@@ -0,0 +1,31 @@
+
+What is efifb?
+===============
+
+This is a generic EFI platform driver for Intel based Apple computers.
+efifb is only for EFI booted Intel Macs.
+
+Supported Hardware
+==================
+
+iMac 17"/20"
+Macbook
+Macbook Pro 15"/17"
+MacMini
+
+How to use it?
+==============
+
+efifb does not have any kind of autodetection of your machine.
+You have to add the following kernel parameters in your elilo.conf:
+	Macbook :
+		video=efifb:macbook
+	MacMini :
+		video=efifb:mini
+	Macbook Pro 15", iMac 17" :
+		video=efifb:i17
+	Macbook Pro 17", iMac 20" :
+		video=efifb:i20
+
+--
+Edgar Hucek <gimli@dark-green.com>

Documentation/fb/imacfb.txt

@@ -1,31 +0,0 @@
-
-What is imacfb?
-===============
-
-This is a generic EFI platform driver for Intel based Apple computers.
-Imacfb is only for EFI booted Intel Macs.
-
-Supported Hardware
-==================
-
-iMac 17"/20"
-Macbook
-Macbook Pro 15"/17"
-MacMini
-
-How to use it?
-==============
-
-Imacfb does not have any kind of autodetection of your machine.
-You have to add the following kernel parameters in your elilo.conf:
-	Macbook :
-		video=imacfb:macbook
-	MacMini :
-		video=imacfb:mini
-	Macbook Pro 15", iMac 17" :
-		video=imacfb:i17
-	Macbook Pro 17", iMac 20" :
-		video=imacfb:i20
-
---
-Edgar Hucek <gimli@dark-green.com>

Documentation/feature-removal-schedule.txt

@@ -241,16 +241,6 @@ Who:	Thomas Gleixner <tglx@linutronix.de>
 
 ---------------------------
 
-What (Why):
-	- xt_recent: the old ipt_recent proc dir
-	  (superseded by /proc/net/xt_recent)
-
-When:	January 2009 or Linux 2.7.0, whichever comes first
-Why:	Superseded by newer revisions or modules
-Who:	Jan Engelhardt <jengelh@computergmbh.de>
-
----------------------------
-
 What:	GPIO autorequest on gpio_direction_{input,output}() in gpiolib
 When:	February 2010
 Why:	All callers should use explicit gpio_request()/gpio_free().
@@ -520,26 +510,21 @@ Who:	Hans de Goede <hdegoede@redhat.com>
 
 ----------------------------
 
-What:	corgikbd, spitzkbd, tosakbd driver
-When:	2.6.35
-Files:	drivers/input/keyboard/{corgi,spitz,tosa}kbd.c
-Why:	We now have a generic GPIO based matrix keyboard driver that
-	are fully capable of handling all the keys on these devices.
-	The original drivers manipulate the GPIO registers directly
-	and so are difficult to maintain.
-Who:	Eric Miao <eric.y.miao@gmail.com>
+What:	sysfs-class-rfkill state file
+When:	Feb 2014
+Files:	net/rfkill/core.c
+Why: 	Documented as obsolete since Feb 2010. This file is limited to 3
+	states while the rfkill drivers can have 4 states.
+Who: 	anybody or Florian Mickler <florian@mickler.org>
 
 ----------------------------
 
-What:	corgi_ssp and corgi_ts driver
-When:	2.6.35
-Files:	arch/arm/mach-pxa/corgi_ssp.c, drivers/input/touchscreen/corgi_ts.c
-Why:	The corgi touchscreen is now deprecated in favour of the generic
-	ads7846.c driver. The noise reduction technique used in corgi_ts.c,
-	that's to wait till vsync before ADC sampling, is also integrated into
-	ads7846 driver now. Provided that the original driver is not generic
-	and is difficult to maintain, it will be removed later.
-Who:	Eric Miao <eric.y.miao@gmail.com>
+What: 	sysfs-class-rfkill claim file
+When:	Feb 2012
+Files:	net/rfkill/core.c
+Why:	It is not possible to claim an rfkill driver since 2007. This is
+	Documented as obsolete since Feb 2010.
+Who: 	anybody or Florian Mickler <florian@mickler.org>
 
 ----------------------------
 
@@ -564,6 +549,16 @@ Who:	Avi Kivity <avi@redhat.com>
 
 ----------------------------
 
+What:	xtime, wall_to_monotonic
+When:	2.6.36+
+Files:	kernel/time/timekeeping.c include/linux/time.h
+Why:	Cleaning up timekeeping internal values. Please use
+	existing timekeeping accessor functions to access
+	the equivalent functionality.
+Who:	John Stultz <johnstul@us.ibm.com>
+
+----------------------------
+
 What:	KVM kernel-allocated memory slots
 When:	July 2010
 Why:	Since 2.6.25, kvm supports user-allocated memory slots, which are
@@ -589,3 +584,75 @@ Why:	Useful in 2003, implementation is a hack.
 	Generally invoked by accident today.
 	Seen as doing more harm than good.
 Who:	Len Brown <len.brown@intel.com>
+
+----------------------------
+
+What:	iwlwifi 50XX module parameters
+When:	2.6.40
+Why:	The "..50" modules parameters were used to configure 5000 series and
+	up devices; different set of module parameters also available for 4965
+	with same functionalities. Consolidate both set into single place
+	in drivers/net/wireless/iwlwifi/iwl-agn.c
+
+Who:	Wey-Yi Guy <wey-yi.w.guy@intel.com>
+
+----------------------------
+
+What:	iwl4965 alias support
+When:	2.6.40
+Why:	Internal alias support has been present in module-init-tools for some
+	time, the MODULE_ALIAS("iwl4965") boilerplate aliases can be removed
+	with no impact.
+
+Who:	Wey-Yi Guy <wey-yi.w.guy@intel.com>
+
+---------------------------
+
+What:	xt_NOTRACK
+Files:	net/netfilter/xt_NOTRACK.c
+When:	April 2011
+Why:	Superseded by xt_CT
+Who:	Netfilter developer team <netfilter-devel@vger.kernel.org>
+
+---------------------------
+
+What:	video4linux /dev/vtx teletext API support
+When:	2.6.35
+Files:	drivers/media/video/saa5246a.c drivers/media/video/saa5249.c
+	include/linux/videotext.h
+Why:	The vtx device nodes have been superseded by vbi device nodes
+	for many years. No applications exist that use the vtx support.
+	Of the two i2c drivers that actually support this API the saa5249
+	has been impossible to use for a year now and no known hardware
+	that supports this device exists. The saa5246a is theoretically
+	supported by the old mxb boards, but it never actually worked.
+
+	In summary: there is no hardware that can use this API and there
+	are no applications actually implementing this API.
+
+	The vtx support still reserves minors 192-223 and we would really
+	like to reuse those for upcoming new functionality. In the unlikely
+	event that new hardware appears that wants to use the functionality
+	provided by the vtx API, then that functionality should be build
+	around the sliced VBI API instead.
+Who:	Hans Verkuil <hverkuil@xs4all.nl>
+
+----------------------------
+
+What:	IRQF_DISABLED
+When:	2.6.36
+Why:	The flag is a NOOP as we run interrupt handlers with interrupts disabled
+Who:	Thomas Gleixner <tglx@linutronix.de>
+
+----------------------------
+
+What:	old ieee1394 subsystem (CONFIG_IEEE1394)
+When:	2.6.37
+Files:	drivers/ieee1394/ except init_ohci1394_dma.c
+Why:	superseded by drivers/firewire/ (CONFIG_FIREWIRE) which offers more
+	features, better performance, and better security, all with smaller
+	and more modern code base
+Who:	Stefan Richter <stefanr@s5r6.in-berlin.de>
+
+----------------------------
+

Documentation/filesystems/00-INDEX

@@ -16,6 +16,8 @@ befs.txt
 	- information about the BeOS filesystem for Linux.
 bfs.txt
 	- info for the SCO UnixWare Boot Filesystem (BFS).
+ceph.txt
+	- info for the Ceph Distributed File System
 cifs.txt
 	- description of the CIFS filesystem.
 coda.txt

Documentation/filesystems/9p.txt

@@ -37,6 +37,15 @@ For Plan 9 From User Space applications (http://swtch.com/plan9)
 
 	mount -t 9p `namespace`/acme /mnt/9 -o trans=unix,uname=$USER
 
+For server running on QEMU host with virtio transport:
+
+	mount -t 9p -o trans=virtio <mount_tag> /mnt/9
+
+where mount_tag is the tag associated by the server to each of the exported
+mount points. Each 9P export is seen by the client as a virtio device with an
+associated "mount_tag" property. Available mount tags can be
+seen by reading /sys/bus/virtio/drivers/9pnet_virtio/virtio<n>/mount_tag files.
+
 OPTIONS
 =======
 
@@ -47,7 +56,7 @@ OPTIONS
 			fd   	- used passed file descriptors for connection
                                 (see rfdno and wfdno)
 			virtio	- connect to the next virtio channel available
-				(from lguest or KVM with trans_virtio module)
+				(from QEMU with trans_virtio module)
 			rdma	- connect to a specified RDMA channel
 
   uname=name	user name to attempt mount as on the remote server.  The
@@ -85,7 +94,12 @@ OPTIONS
 
   port=n	port to connect to on the remote server
 
-  noextend	force legacy mode (no 9p2000.u semantics)
+  noextend	force legacy mode (no 9p2000.u or 9p2000.L semantics)
+
+  version=name	Select 9P protocol version. Valid options are:
+			9p2000          - Legacy mode (same as noextend)
+			9p2000.u        - Use 9P2000.u protocol
+			9p2000.L        - Use 9P2000.L protocol
 
   dfltuid	attempt to mount as a particular uid
 

Documentation/filesystems/Locking

@@ -178,7 +178,7 @@ prototypes:
 locking rules:
 	All except set_page_dirty may block
 
-			BKL	PageLocked(page)	i_sem
+			BKL	PageLocked(page)	i_mutex
 writepage:		no	yes, unlocks (see below)
 readpage:		no	yes, unlocks
 sync_page:		no	maybe
@@ -380,7 +380,7 @@ prototypes:
 	int (*open) (struct inode *, struct file *);
 	int (*flush) (struct file *);
 	int (*release) (struct inode *, struct file *);
-	int (*fsync) (struct file *, struct dentry *, int datasync);
+	int (*fsync) (struct file *, int datasync);
 	int (*aio_fsync) (struct kiocb *, int datasync);
 	int (*fasync) (int, struct file *, int);
 	int (*lock) (struct file *, int, struct file_lock *);
@@ -429,8 +429,9 @@ check_flags:		no
 implementations.  If your fs is not using generic_file_llseek, you
 need to acquire and release the appropriate locks in your ->llseek().
 For many filesystems, it is probably safe to acquire the inode
-semaphore.  Note some filesystems (i.e. remote ones) provide no
-protection for i_size so you will need to use the BKL.
+mutex or just to use i_size_read() instead.
+Note: this does not protect the file->f_pos against concurrent modifications
+since this is something the userspace has to take care about.
 
 Note: ext2_release() was *the* source of contention on fs-intensive
 loads and dropping BKL on ->release() helps to get rid of that (we still

Documentation/filesystems/autofs4-mount-control.txt

@@ -146,7 +146,7 @@ found to be inadequate, in this case. The Generic Netlink system was
 used for this as raw Netlink would lead to a significant increase in
 complexity. There's no question that the Generic Netlink system is an
 elegant solution for common case ioctl functions but it's not a complete
-replacement probably because it's primary purpose in life is to be a
+replacement probably because its primary purpose in life is to be a
 message bus implementation rather than specifically an ioctl replacement.
 While it would be possible to work around this there is one concern
 that lead to the decision to not use it. This is that the autofs

Documentation/filesystems/ceph.txt

@@ -8,7 +8,7 @@ Basic features include:
 
  * POSIX semantics
  * Seamless scaling from 1 to many thousands of nodes
- * High availability and reliability.  No single points of failure.
+ * High availability and reliability.  No single point of failure.
  * N-way replication of data across storage nodes
  * Fast recovery from node failures
  * Automatic rebalancing of data on node addition/removal
@@ -90,11 +90,11 @@ Mount Options
 	Specify the IP and/or port the client should bind to locally.
 	There is normally not much reason to do this.  If the IP is not
 	specified, the client's IP address is determined by looking at the
-	address it's connection to the monitor originates from.
+	address its connection to the monitor originates from.
 
   wsize=X
 	Specify the maximum write size in bytes.  By default there is no
-	maximu.  Ceph will normally size writes based on the file stripe
+	maximum.  Ceph will normally size writes based on the file stripe
 	size.
 
   rsize=X
@@ -115,7 +115,7 @@ Mount Options
 	number of entries in that directory.
 
   nocrc
-	Disable CRC32C calculation for data writes.  If set, the OSD
+	Disable CRC32C calculation for data writes.  If set, the storage node
 	must rely on TCP's error correction to detect data corruption
 	in the data payload.
 
@@ -133,7 +133,8 @@ For more information on Ceph, see the home page at
 	http://ceph.newdream.net/
 
 The Linux kernel client source tree is available at
-	git://ceph.newdream.net/linux-ceph-client.git
+	git://ceph.newdream.net/git/ceph-client.git
+	git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client.git
 
 and the source for the full system is at
-	git://ceph.newdream.net/ceph.git
+	git://ceph.newdream.net/git/ceph.git

Documentation/filesystems/dlmfs.txt

@@ -47,7 +47,7 @@ You'll want to start heartbeating on a volume which all the nodes in
 your lockspace can access. The easiest way to do this is via
 ocfs2_hb_ctl (distributed with ocfs2-tools). Right now it requires
 that an OCFS2 file system be in place so that it can automatically
-find it's heartbeat area, though it will eventually support heartbeat
+find its heartbeat area, though it will eventually support heartbeat
 against raw disks.
 
 Please see the ocfs2_hb_ctl and mkfs.ocfs2 manual pages distributed

Documentation/filesystems/ext3.txt

@@ -59,8 +59,19 @@ commit=nrsec	(*)	Ext3 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
+barrier			the jbd code.  barrier=0 disables, barrier=1 enables.
+nobarrier	(*)	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.
+			The mount options "barrier" and "nobarrier" can
+			also be used to enable or disable barriers, for
+			consistency with other ext3 mount options.
 
 orlov		(*)	This enables the new Orlov block allocator. It is
 			enabled by default.

Documentation/filesystems/fiemap.txt

@@ -38,7 +38,7 @@ flags, it will return EBADR and the contents of fm_flags will contain
 the set of flags which caused the error. If the kernel is compatible
 with all flags passed, the contents of fm_flags will be unmodified.
 It is up to userspace to determine whether rejection of a particular
-flag is fatal to it's operation. This scheme is intended to allow the
+flag is fatal to its operation. This scheme is intended to allow the
 fiemap interface to grow in the future but without losing
 compatibility with old software.
 
@@ -56,7 +56,7 @@ If this flag is set, the kernel will sync the file before mapping extents.
 
 * FIEMAP_FLAG_XATTR
 If this flag is set, the extents returned will describe the inodes
-extended attribute lookup tree, instead of it's data tree.
+extended attribute lookup tree, instead of its data tree.
 
 
 Extent Mapping
@@ -89,7 +89,7 @@ struct fiemap_extent {
 };
 
 All offsets and lengths are in bytes and mirror those on disk.  It is valid
-for an extents logical offset to start before the request or it's logical
+for an extents logical offset to start before the request or its logical
 length to extend past the request.  Unless FIEMAP_EXTENT_NOT_ALIGNED is
 returned, fe_logical, fe_physical, and fe_length will be aligned to the
 block size of the file system.  With the exception of extents flagged as
@@ -125,7 +125,7 @@ been allocated for the file yet.
 
 * FIEMAP_EXTENT_DELALLOC
   - This will also set FIEMAP_EXTENT_UNKNOWN.
-Delayed allocation - while there is data for this extent, it's
+Delayed allocation - while there is data for this extent, its
 physical location has not been allocated yet.
 
 * FIEMAP_EXTENT_ENCODED
@@ -159,7 +159,7 @@ Data is located within a meta data block.
 Data is packed into a block with data from other files.
 
 * FIEMAP_EXTENT_UNWRITTEN
-Unwritten extent - the extent is allocated but it's data has not been
+Unwritten extent - the extent is allocated but its data has not been
 initialized.  This indicates the extent's data will be all zero if read
 through the filesystem but the contents are undefined if read directly from
 the device.
@@ -176,7 +176,7 @@ VFS -> File System Implementation
 
 File systems wishing to support fiemap must implement a ->fiemap callback on
 their inode_operations structure. The fs ->fiemap call is responsible for
-defining it's set of supported fiemap flags, and calling a helper function on
+defining its set of supported fiemap flags, and calling a helper function on
 each discovered extent:
 
 struct inode_operations {

Documentation/filesystems/fuse.txt

@@ -91,7 +91,7 @@ Mount options
 'default_permissions'
 
   By default FUSE doesn't check file access permissions, the
-  filesystem is free to implement it's access policy or leave it to
+  filesystem is free to implement its access policy or leave it to
   the underlying file access mechanism (e.g. in case of network
   filesystems).  This option enables permission checking, restricting
   access based on file mode.  It is usually useful together with the
@@ -171,7 +171,7 @@ or may honor them by sending a reply to the _original_ request, with
 the error set to EINTR.
 
 It is also possible that there's a race between processing the
-original request and it's INTERRUPT request.  There are two possibilities:
+original request and its INTERRUPT request.  There are two possibilities:
 
   1) The INTERRUPT request is processed before the original request is
      processed

Documentation/filesystems/gfs2.txt

@@ -1,7 +1,7 @@
 Global File System
 ------------------
 
-http://sources.redhat.com/cluster/
+http://sources.redhat.com/cluster/wiki/
 
 GFS is a cluster file system. It allows a cluster of computers to
 simultaneously use a block device that is shared between them (with FC,
@@ -36,11 +36,11 @@ GFS2 is not on-disk compatible with previous versions of GFS, but it
 is pretty close.
 
 The following man pages can be found at the URL above:
-  fsck.gfs2	to repair a filesystem
-  gfs2_grow	to expand a filesystem online
-  gfs2_jadd	to add journals to a filesystem online
-  gfs2_tool	to manipulate, examine and tune a filesystem
+  fsck.gfs2		to repair a filesystem
+  gfs2_grow		to expand a filesystem online
+  gfs2_jadd		to add journals to a filesystem online
+  gfs2_tool		to manipulate, examine and tune a filesystem
   gfs2_quota	to examine and change quota values in a filesystem
   gfs2_convert	to convert a gfs filesystem to gfs2 in-place
   mount.gfs2	to help mount(8) mount a filesystem
-  mkfs.gfs2	to make a filesystem
+  mkfs.gfs2		to make a filesystem

Documentation/filesystems/hpfs.txt

@@ -103,7 +103,7 @@ to analyze or change OS2SYS.INI.
 Codepages
 
 HPFS can contain several uppercasing tables for several codepages and each
-file has a pointer to codepage it's name is in. However OS/2 was created in
+file has a pointer to codepage its name is in. However OS/2 was created in
 America where people don't care much about codepages and so multiple codepages
 support is quite buggy. I have Czech OS/2 working in codepage 852 on my disk.
 Once I booted English OS/2 working in cp 850 and I created a file on my 852

Documentation/filesystems/logfs.txt

@@ -59,7 +59,7 @@ Levels
 ------
 
 Garbage collection (GC) may fail if all data is written
-indiscriminately.  One requirement of GC is that data is seperated
+indiscriminately.  One requirement of GC is that data is separated
 roughly according to the distance between the tree root and the data.
 Effectively that means all file data is on level 0, indirect blocks
 are on levels 1, 2, 3 4 or 5 for 1x, 2x, 3x, 4x or 5x indirect blocks,
@@ -67,7 +67,7 @@ respectively.  Inode file data is on level 6 for the inodes and 7-11
 for indirect blocks.
 
 Each segment contains objects of a single level only.  As a result,
-each level requires its own seperate segment to be open for writing.
+each level requires its own separate segment to be open for writing.
 
 Inode File
 ----------
@@ -106,9 +106,9 @@ Vim
 ---
 
 By cleverly predicting the life time of data, it is possible to
-seperate long-living data from short-living data and thereby reduce
+separate long-living data from short-living data and thereby reduce
 the GC overhead later.  Each type of distinc life expectency (vim) can
-have a seperate segment open for writing.  Each (level, vim) tupel can
+have a separate segment open for writing.  Each (level, vim) tupel can
 be open just once.  If an open segment with unknown vim is encountered
 at mount time, it is closed and ignored henceforth.
 

Documentation/filesystems/nfs/nfs41-server.txt

@@ -137,7 +137,7 @@ NS*| OPENATTR             | OPT        |              | Section 18.17  |
    | READ                 | REQ        |              | Section 18.22  |
    | READDIR              | REQ        |              | Section 18.23  |
    | READLINK             | OPT        |              | Section 18.24  |
-NS | RECLAIM_COMPLETE     | REQ        |              | Section 18.51  |
+   | RECLAIM_COMPLETE     | REQ        |              | Section 18.51  |
    | RELEASE_LOCKOWNER    | MNI        |              | N/A            |
    | REMOVE               | REQ        |              | Section 18.25  |
    | RENAME               | REQ        |              | Section 18.26  |

Documentation/filesystems/nfs/rpc-cache.txt

@@ -185,7 +185,7 @@ failed lookup meant a definite 'no'.
 request/response format
 -----------------------
 
-While each cache is free to use it's own format for requests
+While each cache is free to use its own format for requests
 and responses over channel, the following is recommended as
 appropriate and support routines are available to help:
 Each request or response record should be printable ASCII

Documentation/filesystems/nilfs2.txt

@@ -50,8 +50,8 @@ NILFS2 supports the following mount options:
 (*) == default
 
 nobarrier		Disables barriers.
-errors=continue(*)	Keep going on a filesystem error.
-errors=remount-ro	Remount the filesystem read-only on an error.
+errors=continue		Keep going on a filesystem error.
+errors=remount-ro(*)	Remount the filesystem read-only on an error.
 errors=panic		Panic and halt the machine if an error occurs.
 cp=n			Specify the checkpoint-number of the snapshot to be
 			mounted.  Checkpoints and snapshots are listed by lscp

Documentation/filesystems/ocfs2.txt

@@ -80,3 +80,10 @@ user_xattr	(*)	Enables Extended User Attributes.
 nouser_xattr		Disables Extended User Attributes.
 acl			Enables POSIX Access Control Lists support.
 noacl		(*)	Disables POSIX Access Control Lists support.
+resv_level=2	(*)	Set how agressive allocation reservations will be.
+			Valid values are between 0 (reservations off) to 8
+			(maximum space for reservations).
+dir_resv_level=	(*)	By default, directory reservations will scale with file
+			reservations - users should rarely need to change this
+			value. If allocation reservations are turned off, this
+			option will have no effect.