Merge branch 'x86/mm2' into x86/mm

x86/mm2 is testing out fine, but has developed conflicts with x86/mm
due to patches in adjacent code.  Merge them so we can drop x86/mm2
and have a unified branch.

Resolved Conflicts:
	arch/x86/kernel/setup.c

Documentation/kernel-parameters.txt

@@ -594,6 +594,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			is selected automatically. Check
 			Documentation/kdump/kdump.txt for further details.
 
+	crashkernel_low=size[KMG]
+			[KNL, x86] parts under 4G.
+
 	crashkernel=range1:size1[,range2:size2,...][@offset]
 			[KNL] Same as above, but depends on the memory
 			in the running system. The syntax of range is

Documentation/x86/boot.txt

@@ -57,6 +57,10 @@ Protocol 2.10:	(Kernel 2.6.31) Added a protocol for relaxed alignment
 Protocol 2.11:	(Kernel 3.6) Added a field for offset of EFI handover
 		protocol entry point.
 
+Protocol 2.12:	(Kernel 3.9) Added the xloadflags field and extension fields
+	 	to struct boot_params for for loading bzImage and ramdisk
+		above 4G in 64bit.
+
 **** MEMORY LAYOUT
 
 The traditional memory map for the kernel loader, used for Image or
@@ -182,7 +186,7 @@ Offset	Proto	Name		Meaning
 0230/4	2.05+	kernel_alignment Physical addr alignment required for kernel
 0234/1	2.05+	relocatable_kernel Whether kernel is relocatable or not
 0235/1	2.10+	min_alignment	Minimum alignment, as a power of two
-0236/2	N/A	pad3		Unused
+0236/2	2.12+	xloadflags	Boot protocol option flags
 0238/4	2.06+	cmdline_size	Maximum size of the kernel command line
 023C/4	2.07+	hardware_subarch Hardware subarchitecture
 0240/8	2.07+	hardware_subarch_data Subarchitecture-specific data
@@ -582,6 +586,27 @@ Protocol:	2.10+
   misaligned kernel.  Therefore, a loader should typically try each
   power-of-two alignment from kernel_alignment down to this alignment.
 
+Field name:     xloadflags
+Type:           read
+Offset/size:    0x236/2
+Protocol:       2.12+
+
+  This field is a bitmask.
+
+  Bit 0 (read):	XLF_KERNEL_64
+	- If 1, this kernel has the legacy 64-bit entry point at 0x200.
+
+  Bit 1 (read): XLF_CAN_BE_LOADED_ABOVE_4G
+        - If 1, kernel/boot_params/cmdline/ramdisk can be above 4G.
+
+  Bit 2 (read):	XLF_EFI_HANDOVER_32
+	- If 1, the kernel supports the 32-bit EFI handoff entry point
+          given at handover_offset.
+
+  Bit 3 (read): XLF_EFI_HANDOVER_64
+	- If 1, the kernel supports the 64-bit EFI handoff entry point
+          given at handover_offset + 0x200.
+
 Field name:	cmdline_size
 Type:		read
 Offset/size:	0x238/4
@@ -1029,6 +1054,44 @@ must have read/write permission; CS must be __BOOT_CS and DS, ES, SS
 must be __BOOT_DS; interrupt must be disabled; %esi must hold the base
 address of the struct boot_params; %ebp, %edi and %ebx must be zero.
 
+**** 64-bit BOOT PROTOCOL
+
+For machine with 64bit cpus and 64bit kernel, we could use 64bit bootloader
+and we need a 64-bit boot protocol.
+
+In 64-bit boot protocol, the first step in loading a Linux kernel
+should be to setup the boot parameters (struct boot_params,
+traditionally known as "zero page"). The memory for struct boot_params
+could be allocated anywhere (even above 4G) and initialized to all zero.
+Then, the setup header at offset 0x01f1 of kernel image on should be
+loaded into struct boot_params and examined. The end of setup header
+can be calculated as follows:
+
+	0x0202 + byte value at offset 0x0201
+
+In addition to read/modify/write the setup header of the struct
+boot_params as that of 16-bit boot protocol, the boot loader should
+also fill the additional fields of the struct boot_params as described
+in zero-page.txt.
+
+After setting up the struct boot_params, the boot loader can load
+64-bit kernel in the same way as that of 16-bit boot protocol, but
+kernel could be loaded above 4G.
+
+In 64-bit boot protocol, the kernel is started by jumping to the
+64-bit kernel entry point, which is the start address of loaded
+64-bit kernel plus 0x200.
+
+At entry, the CPU must be in 64-bit mode with paging enabled.
+The range with setup_header.init_size from start address of loaded
+kernel and zero page and command line buffer get ident mapping;
+a GDT must be loaded with the descriptors for selectors
+__BOOT_CS(0x10) and __BOOT_DS(0x18); both descriptors must be 4G flat
+segment; __BOOT_CS must have execute/read permission, and __BOOT_DS
+must have read/write permission; CS must be __BOOT_CS and DS, ES, SS
+must be __BOOT_DS; interrupt must be disabled; %rsi must hold the base
+address of the struct boot_params.
+
 **** EFI HANDOVER PROTOCOL
 
 This protocol allows boot loaders to defer initialisation to the EFI

Documentation/x86/zero-page.txt

@@ -19,6 +19,9 @@ Offset	Proto	Name		Meaning
 090/010	ALL	hd1_info	hd1 disk parameter, OBSOLETE!!
 0A0/010	ALL	sys_desc_table	System description table (struct sys_desc_table)
 0B0/010	ALL	olpc_ofw_header	OLPC's OpenFirmware CIF and friends
+0C0/004	ALL	ext_ramdisk_image ramdisk_image high 32bits
+0C4/004	ALL	ext_ramdisk_size  ramdisk_size high 32bits
+0C8/004	ALL	ext_cmd_line_ptr  cmd_line_ptr high 32bits
 140/080	ALL	edid_info	Video mode setup (struct edid_info)
 1C0/020	ALL	efi_info	EFI 32 information (struct efi_info)
 1E0/004	ALL	alk_mem_k	Alternative mem check, in KB
@@ -27,6 +30,7 @@ Offset	Proto	Name		Meaning
 1E9/001	ALL	eddbuf_entries	Number of entries in eddbuf (below)
 1EA/001	ALL	edd_mbr_sig_buf_entries	Number of entries in edd_mbr_sig_buffer
 				(below)
+1EF/001	ALL	sentinel	Used to detect broken bootloaders
 290/040	ALL	edd_mbr_sig_buffer EDD MBR signatures
 2D0/A00	ALL	e820_map	E820 memory map table
 				(array of struct e820entry)

arch/mips/cavium-octeon/dma-octeon.c

@@ -317,7 +317,8 @@ void __init plat_swiotlb_setup(void)
 
 	octeon_swiotlb = alloc_bootmem_low_pages(swiotlbsize);
 
-	swiotlb_init_with_tbl(octeon_swiotlb, swiotlb_nslabs, 1);
+	if (swiotlb_init_with_tbl(octeon_swiotlb, swiotlb_nslabs, 1) == -ENOMEM)
+		panic("Cannot allocate SWIOTLB buffer");
 
 	mips_dma_map_ops = &octeon_linear_dma_map_ops.dma_map_ops;
 }

arch/sparc/mm/init_64.c

@@ -2021,6 +2021,16 @@ static void __init patch_tlb_miss_handler_bitmap(void)
 	flushi(&valid_addr_bitmap_insn[0]);
 }
 
+static void __init register_page_bootmem_info(void)
+{
+#ifdef CONFIG_NEED_MULTIPLE_NODES
+	int i;
+
+	for_each_online_node(i)
+		if (NODE_DATA(i)->node_spanned_pages)
+			register_page_bootmem_info_node(NODE_DATA(i));
+#endif
+}
 void __init mem_init(void)
 {
 	unsigned long codepages, datapages, initpages;
@@ -2038,20 +2048,8 @@ void __init mem_init(void)
 
 	high_memory = __va(last_valid_pfn << PAGE_SHIFT);
 
-#ifdef CONFIG_NEED_MULTIPLE_NODES
-	{
-		int i;
-		for_each_online_node(i) {
-			if (NODE_DATA(i)->node_spanned_pages != 0) {
-				totalram_pages +=
-					free_all_bootmem_node(NODE_DATA(i));
-			}
-		}
-		totalram_pages += free_low_memory_core_early(MAX_NUMNODES);
-	}
-#else
+	register_page_bootmem_info();
 	totalram_pages = free_all_bootmem();
-#endif
 
 	/* We subtract one to account for the mem_map_zero page
 	 * allocated below.

arch/x86/boot/boot.h

@@ -285,16 +285,26 @@ struct biosregs {
 void intcall(u8 int_no, const struct biosregs *ireg, struct biosregs *oreg);
 
 /* cmdline.c */
-int __cmdline_find_option(u32 cmdline_ptr, const char *option, char *buffer, int bufsize);
-int __cmdline_find_option_bool(u32 cmdline_ptr, const char *option);
+int __cmdline_find_option(unsigned long cmdline_ptr, const char *option, char *buffer, int bufsize);
+int __cmdline_find_option_bool(unsigned long cmdline_ptr, const char *option);
 static inline int cmdline_find_option(const char *option, char *buffer, int bufsize)
 {
-	return __cmdline_find_option(boot_params.hdr.cmd_line_ptr, option, buffer, bufsize);
+	unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
+
+	if (cmd_line_ptr >= 0x100000)
+		return -1;      /* inaccessible */
+
+	return __cmdline_find_option(cmd_line_ptr, option, buffer, bufsize);
 }
 
 static inline int cmdline_find_option_bool(const char *option)
 {
-	return __cmdline_find_option_bool(boot_params.hdr.cmd_line_ptr, option);
+	unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
+
+	if (cmd_line_ptr >= 0x100000)
+		return -1;      /* inaccessible */
+
+	return __cmdline_find_option_bool(cmd_line_ptr, option);
 }
 
 

arch/x86/boot/cmdline.c

@@ -27,7 +27,7 @@ static inline int myisspace(u8 c)
  * Returns the length of the argument (regardless of if it was
  * truncated to fit in the buffer), or -1 on not found.
  */
-int __cmdline_find_option(u32 cmdline_ptr, const char *option, char *buffer, int bufsize)
+int __cmdline_find_option(unsigned long cmdline_ptr, const char *option, char *buffer, int bufsize)
 {
 	addr_t cptr;
 	char c;
@@ -41,8 +41,8 @@ int __cmdline_find_option(u32 cmdline_ptr, const char *option, char *buffer, int
 		st_bufcpy	/* Copying this to buffer */
 	} state = st_wordstart;
 
-	if (!cmdline_ptr || cmdline_ptr >= 0x100000)
-		return -1;	/* No command line, or inaccessible */
+	if (!cmdline_ptr)
+		return -1;      /* No command line */
 
 	cptr = cmdline_ptr & 0xf;
 	set_fs(cmdline_ptr >> 4);
@@ -99,7 +99,7 @@ int __cmdline_find_option(u32 cmdline_ptr, const char *option, char *buffer, int
  * Returns the position of that option (starts counting with 1)
  * or 0 on not found
  */
-int __cmdline_find_option_bool(u32 cmdline_ptr, const char *option)
+int __cmdline_find_option_bool(unsigned long cmdline_ptr, const char *option)
 {
 	addr_t cptr;
 	char c;
@@ -111,8 +111,8 @@ int __cmdline_find_option_bool(u32 cmdline_ptr, const char *option)
 		st_wordskip,	/* Miscompare, skip */
 	} state = st_wordstart;
 
-	if (!cmdline_ptr || cmdline_ptr >= 0x100000)
-		return -1;	/* No command line, or inaccessible */
+	if (!cmdline_ptr)
+		return -1;      /* No command line */
 
 	cptr = cmdline_ptr & 0xf;
 	set_fs(cmdline_ptr >> 4);

arch/x86/boot/compressed/cmdline.c

@@ -13,13 +13,21 @@ static inline char rdfs8(addr_t addr)
 	return *((char *)(fs + addr));
 }
 #include "../cmdline.c"
+static unsigned long get_cmd_line_ptr(void)
+{
+	unsigned long cmd_line_ptr = real_mode->hdr.cmd_line_ptr;
+
+	cmd_line_ptr |= (u64)real_mode->ext_cmd_line_ptr << 32;
+
+	return cmd_line_ptr;
+}
 int cmdline_find_option(const char *option, char *buffer, int bufsize)
 {
-	return __cmdline_find_option(real_mode->hdr.cmd_line_ptr, option, buffer, bufsize);
+	return __cmdline_find_option(get_cmd_line_ptr(), option, buffer, bufsize);
 }
 int cmdline_find_option_bool(const char *option)
 {
-	return __cmdline_find_option_bool(real_mode->hdr.cmd_line_ptr, option);
+	return __cmdline_find_option_bool(get_cmd_line_ptr(), option);
 }
 
 #endif

arch/x86/boot/compressed/head_64.S

@@ -37,6 +37,12 @@
 	__HEAD
 	.code32
 ENTRY(startup_32)
+	/*
+	 * 32bit entry is 0 and it is ABI so immutable!
+	 * If we come here directly from a bootloader,
+	 * kernel(text+data+bss+brk) ramdisk, zero_page, command line
+	 * all need to be under the 4G limit.
+	 */
 	cld
 	/*
 	 * Test KEEP_SEGMENTS flag to see if the bootloader is asking
@@ -154,6 +160,12 @@ ENTRY(startup_32)
 	btsl	$_EFER_LME, %eax
 	wrmsr
 
+	/* After gdt is loaded */
+	xorl	%eax, %eax
+	lldt	%ax
+	movl    $0x20, %eax
+	ltr	%ax
+
 	/*
 	 * Setup for the jump to 64bit mode
 	 *
@@ -176,28 +188,18 @@ ENTRY(startup_32)
 	lret
 ENDPROC(startup_32)
 
-no_longmode:
-	/* This isn't an x86-64 CPU so hang */
-1:
-	hlt
-	jmp     1b
-
-#include "../../kernel/verify_cpu.S"
-
-	/*
-	 * Be careful here startup_64 needs to be at a predictable
-	 * address so I can export it in an ELF header.  Bootloaders
-	 * should look at the ELF header to find this address, as
-	 * it may change in the future.
-	 */
 	.code64
 	.org 0x200
 ENTRY(startup_64)
 	/*
+	 * 64bit entry is 0x200 and it is ABI so immutable!
 	 * We come here either from startup_32 or directly from a
-	 * 64bit bootloader.  If we come here from a bootloader we depend on
-	 * an identity mapped page table being provied that maps our
-	 * entire text+data+bss and hopefully all of memory.
+	 * 64bit bootloader.
+	 * If we come here from a bootloader, kernel(text+data+bss+brk),
+	 * ramdisk, zero_page, command line could be above 4G.
+	 * We depend on an identity mapped page table being provided
+	 * that maps our entire kernel(text+data+bss+brk), zero page
+	 * and command line.
 	 */
 #ifdef CONFIG_EFI_STUB
 	/*
@@ -247,9 +249,6 @@ preferred_addr:
 	movl	%eax, %ss
 	movl	%eax, %fs
 	movl	%eax, %gs
-	lldt	%ax
-	movl    $0x20, %eax
-	ltr	%ax
 
 	/*
 	 * Compute the decompressed kernel start address.  It is where
@@ -349,6 +348,15 @@ relocated:
  */
 	jmp	*%rbp
 
+	.code32
+no_longmode:
+	/* This isn't an x86-64 CPU so hang */
+1:
+	hlt
+	jmp     1b
+
+#include "../../kernel/verify_cpu.S"
+
 	.data
 gdt:
 	.word	gdt_end - gdt

arch/x86/boot/compressed/misc.c

@@ -325,6 +325,8 @@ asmlinkage void decompress_kernel(void *rmode, memptr heap,
 {
 	real_mode = rmode;
 
+	sanitize_boot_params(real_mode);
+
 	if (real_mode->screen_info.orig_video_mode == 7) {
 		vidmem = (char *) 0xb0000;
 		vidport = 0x3b4;

arch/x86/boot/compressed/misc.h

@@ -18,6 +18,7 @@
 #include <asm/page.h>
 #include <asm/boot.h>
 #include <asm/bootparam.h>
+#include <asm/bootparam_utils.h>
 
 #define BOOT_BOOT_H
 #include "../ctype.h"

arch/x86/boot/header.S

@@ -21,6 +21,7 @@
 #include <asm/e820.h>
 #include <asm/page_types.h>
 #include <asm/setup.h>
+#include <asm/bootparam.h>
 #include "boot.h"
 #include "voffset.h"
 #include "zoffset.h"
@@ -255,6 +256,9 @@ section_table:
 	# header, from the old boot sector.
 
 	.section ".header", "a"
+	.globl	sentinel
+sentinel:	.byte 0xff, 0xff        /* Used to detect broken loaders */
+
 	.globl	hdr
 hdr:
 setup_sects:	.byte 0			/* Filled in by build.c */
@@ -279,7 +283,7 @@ _start:
 	# Part 2 of the header, from the old setup.S
 
 		.ascii	"HdrS"		# header signature
-		.word	0x020b		# header version number (>= 0x0105)
+		.word	0x020c		# header version number (>= 0x0105)
 					# or else old loadlin-1.5 will fail)
 		.globl realmode_swtch
 realmode_swtch:	.word	0, 0		# default_switch, SETUPSEG
@@ -297,13 +301,7 @@ type_of_loader:	.byte	0		# 0 means ancient bootloader, newer
 
 # flags, unused bits must be zero (RFU) bit within loadflags
 loadflags:
-LOADED_HIGH	= 1			# If set, the kernel is loaded high
-CAN_USE_HEAP	= 0x80			# If set, the loader also has set
-					# heap_end_ptr to tell how much
-					# space behind setup.S can be used for
-					# heap purposes.
-					# Only the loader knows what is free
-		.byte	LOADED_HIGH
+		.byte	LOADED_HIGH	# The kernel is to be loaded high
 
 setup_move_size: .word  0x8000		# size to move, when setup is not
 					# loaded at 0x90000. We will move setup
@@ -369,7 +367,31 @@ relocatable_kernel:    .byte 1
 relocatable_kernel:    .byte 0
 #endif
 min_alignment:		.byte MIN_KERNEL_ALIGN_LG2	# minimum alignment
-pad3:			.word 0
+
+xloadflags:
+#ifdef CONFIG_X86_64
+# define XLF0 XLF_KERNEL_64			/* 64-bit kernel */
+#else
+# define XLF0 0
+#endif
+
+#if defined(CONFIG_RELOCATABLE) && defined(CONFIG_X86_64)
+   /* kernel/boot_param/ramdisk could be loaded above 4g */
+# define XLF1 XLF_CAN_BE_LOADED_ABOVE_4G
+#else
+# define XLF1 0
+#endif
+
+#ifdef CONFIG_EFI_STUB
+# ifdef CONFIG_X86_64
+#  define XLF23 XLF_EFI_HANDOVER_64		/* 64-bit EFI handover ok */
+# else
+#  define XLF23 XLF_EFI_HANDOVER_32		/* 32-bit EFI handover ok */
+# endif
+#else
+# define XLF23 0
+#endif
+			.word XLF0 | XLF1 | XLF23
 
 cmdline_size:   .long   COMMAND_LINE_SIZE-1     #length of the command line,
                                                 #added with boot protocol
@@ -397,8 +419,13 @@ pref_address:		.quad LOAD_PHYSICAL_ADDR	# preferred load addr
 #define INIT_SIZE VO_INIT_SIZE
 #endif
 init_size:		.long INIT_SIZE		# kernel initialization size
-handover_offset:	.long 0x30		# offset to the handover
+handover_offset:
+#ifdef CONFIG_EFI_STUB
+  			.long 0x30		# offset to the handover
 						# protocol entry point
+#else
+			.long 0
+#endif
 
 # End of setup header #####################################################
 

arch/x86/boot/setup.ld

@@ -13,7 +13,7 @@ SECTIONS
 	.bstext		: { *(.bstext) }
 	.bsdata		: { *(.bsdata) }
 
-	. = 497;
+	. = 495;
 	.header		: { *(.header) }
 	.entrytext	: { *(.entrytext) }
 	.inittext	: { *(.inittext) }

arch/x86/include/asm/bootparam_utils.h

@@ -0,0 +1,38 @@
+#ifndef _ASM_X86_BOOTPARAM_UTILS_H
+#define _ASM_X86_BOOTPARAM_UTILS_H
+
+#include <asm/bootparam.h>
+
+/*
+ * This file is included from multiple environments.  Do not
+ * add completing #includes to make it standalone.
+ */
+
+/*
+ * Deal with bootloaders which fail to initialize unknown fields in
+ * boot_params to zero.  The list fields in this list are taken from
+ * analysis of kexec-tools; if other broken bootloaders initialize a
+ * different set of fields we will need to figure out how to disambiguate.
+ *
+ */
+static void sanitize_boot_params(struct boot_params *boot_params)
+{
+	if (boot_params->sentinel) {
+		/*fields in boot_params are not valid, clear them */
+		memset(&boot_params->olpc_ofw_header, 0,
+		       (char *)&boot_params->alt_mem_k -
+			(char *)&boot_params->olpc_ofw_header);
+		memset(&boot_params->kbd_status, 0,
+		       (char *)&boot_params->hdr -
+		       (char *)&boot_params->kbd_status);
+		memset(&boot_params->_pad7[0], 0,
+		       (char *)&boot_params->edd_mbr_sig_buffer[0] -
+			(char *)&boot_params->_pad7[0]);
+		memset(&boot_params->_pad8[0], 0,
+		       (char *)&boot_params->eddbuf[0] -
+			(char *)&boot_params->_pad8[0]);
+		memset(&boot_params->_pad9[0], 0, sizeof(boot_params->_pad9));
+	}
+}
+
+#endif /* _ASM_X86_BOOTPARAM_UTILS_H */

arch/x86/include/asm/init.h

@@ -1,20 +1,14 @@
-#ifndef _ASM_X86_INIT_32_H
-#define _ASM_X86_INIT_32_H
+#ifndef _ASM_X86_INIT_H
+#define _ASM_X86_INIT_H
 
-#ifdef CONFIG_X86_32
-extern void __init early_ioremap_page_table_range_init(void);
-#endif
+struct x86_mapping_info {
+	void *(*alloc_pgt_page)(void *); /* allocate buf for page table */
+	void *context;			 /* context for alloc_pgt_page */
+	unsigned long pmd_flag;		 /* page flag for PMD entry */
+	bool kernel_mapping;		 /* kernel mapping or ident mapping */
+};
 
-extern void __init zone_sizes_init(void);
+int kernel_ident_mapping_init(struct x86_mapping_info *info, pgd_t *pgd_page,
+				unsigned long addr, unsigned long end);
 
-extern unsigned long __init
-kernel_physical_mapping_init(unsigned long start,
-			     unsigned long end,
-			     unsigned long page_size_mask);
-
-
-extern unsigned long __initdata pgt_buf_start;
-extern unsigned long __meminitdata pgt_buf_end;
-extern unsigned long __meminitdata pgt_buf_top;
-
-#endif /* _ASM_X86_INIT_32_H */
+#endif /* _ASM_X86_INIT_H */

arch/x86/include/asm/kexec.h

@@ -48,11 +48,11 @@
 # define vmcore_elf_check_arch_cross(x) ((x)->e_machine == EM_X86_64)
 #else
 /* Maximum physical address we can use pages from */
-# define KEXEC_SOURCE_MEMORY_LIMIT      (0xFFFFFFFFFFUL)
+# define KEXEC_SOURCE_MEMORY_LIMIT      (MAXMEM-1)
 /* Maximum address we can reach in physical address mode */
-# define KEXEC_DESTINATION_MEMORY_LIMIT (0xFFFFFFFFFFUL)
+# define KEXEC_DESTINATION_MEMORY_LIMIT (MAXMEM-1)
 /* Maximum address we can use for the control pages */
-# define KEXEC_CONTROL_MEMORY_LIMIT     (0xFFFFFFFFFFUL)
+# define KEXEC_CONTROL_MEMORY_LIMIT     (MAXMEM-1)
 
 /* Allocate one page for the pdp and the second for the code */
 # define KEXEC_CONTROL_PAGE_SIZE  (4096UL + 4096UL)

arch/x86/include/asm/numa.h

@@ -54,8 +54,6 @@ static inline int numa_cpu_node(int cpu)
 
 #ifdef CONFIG_X86_32
 # include <asm/numa_32.h>
-#else
-# include <asm/numa_64.h>
 #endif
 
 #ifdef CONFIG_NUMA

arch/x86/include/asm/numa_64.h

@@ -1,6 +0,0 @@
-#ifndef _ASM_X86_NUMA_64_H
-#define _ASM_X86_NUMA_64_H
-
-extern unsigned long numa_free_all_bootmem(void);
-
-#endif /* _ASM_X86_NUMA_64_H */

arch/x86/include/asm/page.h

@@ -17,6 +17,10 @@
 
 struct page;
 
+#include <linux/range.h>
+extern struct range pfn_mapped[];
+extern int nr_pfn_mapped;
+
 static inline void clear_user_page(void *page, unsigned long vaddr,
 				   struct page *pg)
 {

arch/x86/include/asm/page_types.h

@@ -51,6 +51,8 @@ static inline phys_addr_t get_max_mapped(void)
 	return (phys_addr_t)max_pfn_mapped << PAGE_SHIFT;
 }
 
+bool pfn_range_is_mapped(unsigned long start_pfn, unsigned long end_pfn);
+
 extern unsigned long init_memory_mapping(unsigned long start,
 					 unsigned long end);
 

arch/x86/include/asm/pgtable.h

@@ -616,6 +616,8 @@ static inline int pgd_none(pgd_t pgd)
 #ifndef __ASSEMBLY__
 
 extern int direct_gbpages;
+void init_mem_mapping(void);
+void early_alloc_pgt_buf(void);
 
 /* local pte updates need not use xchg for locking */
 static inline pte_t native_local_ptep_get_and_clear(pte_t *ptep)

arch/x86/include/asm/pgtable_64_types.h

@@ -1,6 +1,8 @@
 #ifndef _ASM_X86_PGTABLE_64_DEFS_H
 #define _ASM_X86_PGTABLE_64_DEFS_H
 
+#include <asm/sparsemem.h>
+
 #ifndef __ASSEMBLY__
 #include <linux/types.h>
 
@@ -60,4 +62,6 @@ typedef struct { pteval_t pte; } pte_t;
 #define MODULES_END      _AC(0xffffffffff000000, UL)
 #define MODULES_LEN   (MODULES_END - MODULES_VADDR)
 
+#define EARLY_DYNAMIC_PAGE_TABLES	64
+
 #endif /* _ASM_X86_PGTABLE_64_DEFS_H */

arch/x86/include/asm/pgtable_types.h

@@ -321,7 +321,6 @@ int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
 /* Install a pte for a particular vaddr in kernel space. */
 void set_pte_vaddr(unsigned long vaddr, pte_t pte);
 
-extern void native_pagetable_reserve(u64 start, u64 end);
 #ifdef CONFIG_X86_32
 extern void native_pagetable_init(void);
 #else

arch/x86/include/asm/processor.h

@@ -731,6 +731,7 @@ extern void enable_sep_cpu(void);
 extern int sysenter_setup(void);
 
 extern void early_trap_init(void);
+void early_trap_pf_init(void);
 
 /* Defined in head.S */
 extern struct desc_ptr		early_gdt_descr;

arch/x86/include/asm/realmode.h

@@ -58,6 +58,7 @@ extern unsigned char boot_gdt[];
 extern unsigned char secondary_startup_64[];
 #endif
 
-extern void __init setup_real_mode(void);
+void reserve_real_mode(void);
+void setup_real_mode(void);
 
 #endif /* _ARCH_X86_REALMODE_H */

arch/x86/include/asm/x86_init.h

@@ -68,17 +68,6 @@ struct x86_init_oem {
 	void (*banner)(void);
 };
 
-/**
- * struct x86_init_mapping - platform specific initial kernel pagetable setup
- * @pagetable_reserve:	reserve a range of addresses for kernel pagetable usage
- *
- * For more details on the purpose of this hook, look in
- * init_memory_mapping and the commit that added it.
- */
-struct x86_init_mapping {
-	void (*pagetable_reserve)(u64 start, u64 end);
-};
-
 /**
  * struct x86_init_paging - platform specific paging functions
  * @pagetable_init:	platform specific paging initialization call to setup
@@ -136,7 +125,6 @@ struct x86_init_ops {
 	struct x86_init_mpparse		mpparse;
 	struct x86_init_irqs		irqs;
 	struct x86_init_oem		oem;
-	struct x86_init_mapping		mapping;
 	struct x86_init_paging		paging;
 	struct x86_init_timers		timers;
 	struct x86_init_iommu		iommu;

arch/x86/include/uapi/asm/bootparam.h

@@ -1,6 +1,31 @@
 #ifndef _ASM_X86_BOOTPARAM_H
 #define _ASM_X86_BOOTPARAM_H
 
+/* setup_data types */
+#define SETUP_NONE			0
+#define SETUP_E820_EXT			1
+#define SETUP_DTB			2
+#define SETUP_PCI			3
+
+/* ram_size flags */
+#define RAMDISK_IMAGE_START_MASK	0x07FF
+#define RAMDISK_PROMPT_FLAG		0x8000
+#define RAMDISK_LOAD_FLAG		0x4000
+
+/* loadflags */
+#define LOADED_HIGH	(1<<0)
+#define QUIET_FLAG	(1<<5)
+#define KEEP_SEGMENTS	(1<<6)
+#define CAN_USE_HEAP	(1<<7)
+
+/* xloadflags */
+#define XLF_KERNEL_64			(1<<0)
+#define XLF_CAN_BE_LOADED_ABOVE_4G	(1<<1)
+#define XLF_EFI_HANDOVER_32		(1<<2)
+#define XLF_EFI_HANDOVER_64		(1<<3)
+
+#ifndef __ASSEMBLY__
+
 #include <linux/types.h>
 #include <linux/screen_info.h>
 #include <linux/apm_bios.h>
@@ -9,12 +34,6 @@
 #include <asm/ist.h>
 #include <video/edid.h>
 
-/* setup data types */
-#define SETUP_NONE			0
-#define SETUP_E820_EXT			1
-#define SETUP_DTB			2
-#define SETUP_PCI			3
-
 /* extensible setup data list node */
 struct setup_data {
 	__u64 next;
@@ -28,9 +47,6 @@ struct setup_header {
 	__u16	root_flags;
 	__u32	syssize;
 	__u16	ram_size;
-#define RAMDISK_IMAGE_START_MASK	0x07FF
-#define RAMDISK_PROMPT_FLAG		0x8000
-#define RAMDISK_LOAD_FLAG		0x4000
 	__u16	vid_mode;
 	__u16	root_dev;
 	__u16	boot_flag;
@@ -42,10 +58,6 @@ struct setup_header {
 	__u16	kernel_version;
 	__u8	type_of_loader;
 	__u8	loadflags;
-#define LOADED_HIGH	(1<<0)
-#define QUIET_FLAG	(1<<5)
-#define KEEP_SEGMENTS	(1<<6)
-#define CAN_USE_HEAP	(1<<7)
 	__u16	setup_move_size;
 	__u32	code32_start;
 	__u32	ramdisk_image;
@@ -58,7 +70,8 @@ struct setup_header {
 	__u32	initrd_addr_max;
 	__u32	kernel_alignment;
 	__u8	relocatable_kernel;
-	__u8	_pad2[3];
+	__u8	min_alignment;
+	__u16	xloadflags;
 	__u32	cmdline_size;
 	__u32	hardware_subarch;
 	__u64	hardware_subarch_data;
@@ -106,7 +119,10 @@ struct boot_params {
 	__u8  hd1_info[16];	/* obsolete! */		/* 0x090 */
 	struct sys_desc_table sys_desc_table;		/* 0x0a0 */
 	struct olpc_ofw_header olpc_ofw_header;		/* 0x0b0 */
-	__u8  _pad4[128];				/* 0x0c0 */
+	__u32 ext_ramdisk_image;			/* 0x0c0 */
+	__u32 ext_ramdisk_size;				/* 0x0c4 */
+	__u32 ext_cmd_line_ptr;				/* 0x0c8 */
+	__u8  _pad4[116];				/* 0x0cc */
 	struct edid_info edid_info;			/* 0x140 */
 	struct efi_info efi_info;			/* 0x1c0 */
 	__u32 alt_mem_k;				/* 0x1e0 */
@@ -115,7 +131,20 @@ struct boot_params {
 	__u8  eddbuf_entries;				/* 0x1e9 */
 	__u8  edd_mbr_sig_buf_entries;			/* 0x1ea */
 	__u8  kbd_status;				/* 0x1eb */
-	__u8  _pad6[5];					/* 0x1ec */
+	__u8  _pad5[3];					/* 0x1ec */
+	/*
+	 * The sentinel is set to a nonzero value (0xff) in header.S.
+	 *
+	 * A bootloader is supposed to only take setup_header and put
+	 * it into a clean boot_params buffer. If it turns out that
+	 * it is clumsy or too generous with the buffer, it most
+	 * probably will pick up the sentinel variable too. The fact
+	 * that this variable then is still 0xff will let kernel
+	 * know that some variables in boot_params are invalid and
+	 * kernel should zero out certain portions of boot_params.
+	 */
+	__u8  sentinel;					/* 0x1ef */
+	__u8  _pad6[1];					/* 0x1f0 */
 	struct setup_header hdr;    /* setup header */	/* 0x1f1 */
 	__u8  _pad7[0x290-0x1f1-sizeof(struct setup_header)];
 	__u32 edd_mbr_sig_buffer[EDD_MBR_SIG_MAX];	/* 0x290 */
@@ -134,6 +163,6 @@ enum {
 	X86_NR_SUBARCHS,
 };
 
-
+#endif /* __ASSEMBLY__ */
 
 #endif /* _ASM_X86_BOOTPARAM_H */

arch/x86/kernel/acpi/boot.c

@@ -51,7 +51,6 @@ EXPORT_SYMBOL(acpi_disabled);
 
 #ifdef	CONFIG_X86_64
 # include <asm/proto.h>
-# include <asm/numa_64.h>
 #endif				/* X86 */
 
 #define BAD_MADT_ENTRY(entry, end) (					    \

arch/x86/kernel/amd_gart_64.c

@@ -768,10 +768,9 @@ int __init gart_iommu_init(void)
 	aper_base	= info.aper_base;
 	end_pfn		= (aper_base>>PAGE_SHIFT) + (aper_size>>PAGE_SHIFT);
 
-	if (end_pfn > max_low_pfn_mapped) {
-		start_pfn = (aper_base>>PAGE_SHIFT);
+	start_pfn = PFN_DOWN(aper_base);
+	if (!pfn_range_is_mapped(start_pfn, end_pfn))
 		init_memory_mapping(start_pfn<<PAGE_SHIFT, end_pfn<<PAGE_SHIFT);
-	}
 
 	pr_info("PCI-DMA: using GART IOMMU.\n");
 	iommu_size = check_iommu_size(info.aper_base, aper_size);

arch/x86/kernel/cpu/amd.c

@@ -12,7 +12,6 @@
 #include <asm/pci-direct.h>
 
 #ifdef CONFIG_X86_64
-# include <asm/numa_64.h>
 # include <asm/mmconfig.h>
 # include <asm/cacheflush.h>
 #endif
@@ -685,12 +684,10 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
 		 * benefit in doing so.
 		 */
 		if (!rdmsrl_safe(MSR_K8_TSEG_ADDR, &tseg)) {
+			unsigned long pfn = tseg >> PAGE_SHIFT;
+
 			printk(KERN_DEBUG "tseg: %010llx\n", tseg);
-			if ((tseg>>PMD_SHIFT) <
-				(max_low_pfn_mapped>>(PMD_SHIFT-PAGE_SHIFT)) ||
-				((tseg>>PMD_SHIFT) <
-				(max_pfn_mapped>>(PMD_SHIFT-PAGE_SHIFT)) &&
-				(tseg>>PMD_SHIFT) >= (1ULL<<(32 - PMD_SHIFT))))
+			if (pfn_range_is_mapped(pfn, pfn + 1))
 				set_memory_4k((unsigned long)__va(tseg), 1);
 		}
 	}

arch/x86/kernel/cpu/intel.c

@@ -17,7 +17,6 @@
 
 #ifdef CONFIG_X86_64
 #include <linux/topology.h>
-#include <asm/numa_64.h>
 #endif
 
 #include "cpu.h"

arch/x86/kernel/e820.c

@@ -835,7 +835,7 @@ static int __init parse_memopt(char *p)
 }
 early_param("mem", parse_memopt);
 
-static int __init parse_memmap_opt(char *p)
+static int __init parse_memmap_one(char *p)
 {
 	char *oldp;
 	u64 start_at, mem_size;
@@ -877,6 +877,20 @@ static int __init parse_memmap_opt(char *p)
 
 	return *p == '\0' ? 0 : -EINVAL;
 }
+static int __init parse_memmap_opt(char *str)
+{
+	while (str) {
+		char *k = strchr(str, ',');
+
+		if (k)
+			*k++ = 0;
+
+		parse_memmap_one(str);
+		str = k;
+	}
+
+	return 0;
+}
 early_param("memmap", parse_memmap_opt);
 
 void __init finish_e820_parsing(void)

arch/x86/kernel/head32.c

@@ -18,6 +18,7 @@
 #include <asm/io_apic.h>
 #include <asm/bios_ebda.h>
 #include <asm/tlbflush.h>
+#include <asm/bootparam_utils.h>
 
 static void __init i386_default_early_setup(void)
 {
@@ -30,19 +31,7 @@ static void __init i386_default_early_setup(void)
 
 void __init i386_start_kernel(void)
 {
-	memblock_reserve(__pa_symbol(_text),
-			 (unsigned long)__bss_stop - (unsigned long)_text);
-
-#ifdef CONFIG_BLK_DEV_INITRD
-	/* Reserve INITRD */
-	if (boot_params.hdr.type_of_loader && boot_params.hdr.ramdisk_image) {
-		/* Assume only end is not page aligned */
-		u64 ramdisk_image = boot_params.hdr.ramdisk_image;
-		u64 ramdisk_size  = boot_params.hdr.ramdisk_size;
-		u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
-		memblock_reserve(ramdisk_image, ramdisk_end - ramdisk_image);
-	}
-#endif
+	sanitize_boot_params(&boot_params);
 
 	/* Call the subarch specific early setup function */
 	switch (boot_params.hdr.hardware_subarch) {
@@ -57,11 +46,5 @@ void __init i386_start_kernel(void)
 		break;
 	}
 
-	/*
-	 * At this point everything still needed from the boot loader
-	 * or BIOS or kernel text should be early reserved or marked not
-	 * RAM in e820. All other memory is free game.
-	 */
-
 	start_kernel();
 }

arch/x86/kernel/head64.c

@@ -25,12 +25,83 @@
 #include <asm/kdebug.h>
 #include <asm/e820.h>
 #include <asm/bios_ebda.h>
+#include <asm/bootparam_utils.h>
 
-static void __init zap_identity_mappings(void)
+/*
+ * Manage page tables very early on.
+ */
+extern pgd_t early_level4_pgt[PTRS_PER_PGD];
+extern pmd_t early_dynamic_pgts[EARLY_DYNAMIC_PAGE_TABLES][PTRS_PER_PMD];
+static unsigned int __initdata next_early_pgt = 2;
+
+/* Wipe all early page tables except for the kernel symbol map */
+static void __init reset_early_page_tables(void)
+{
+	unsigned long i;
+
+	for (i = 0; i < PTRS_PER_PGD-1; i++)
+		early_level4_pgt[i].pgd = 0;
+
+	next_early_pgt = 0;
+
+	write_cr3(__pa(early_level4_pgt));
+}
+
+/* Create a new PMD entry */
+int __init early_make_pgtable(unsigned long address)
 {
-	pgd_t *pgd = pgd_offset_k(0UL);
-	pgd_clear(pgd);
-	__flush_tlb_all();
+	unsigned long physaddr = address - __PAGE_OFFSET;
+	unsigned long i;
+	pgdval_t pgd, *pgd_p;
+	pudval_t pud, *pud_p;
+	pmdval_t pmd, *pmd_p;
+
+	/* Invalid address or early pgt is done ?  */
+	if (physaddr >= MAXMEM || read_cr3() != __pa(early_level4_pgt))
+		return -1;
+
+again:
+	pgd_p = &early_level4_pgt[pgd_index(address)].pgd;
+	pgd = *pgd_p;
+
+	/*
+	 * The use of __START_KERNEL_map rather than __PAGE_OFFSET here is
+	 * critical -- __PAGE_OFFSET would point us back into the dynamic
+	 * range and we might end up looping forever...
+	 */
+	if (pgd)
+		pud_p = (pudval_t *)((pgd & PTE_PFN_MASK) + __START_KERNEL_map - phys_base);
+	else {
+		if (next_early_pgt >= EARLY_DYNAMIC_PAGE_TABLES) {
+			reset_early_page_tables();
+			goto again;
+		}
+
+		pud_p = (pudval_t *)early_dynamic_pgts[next_early_pgt++];
+		for (i = 0; i < PTRS_PER_PUD; i++)
+			pud_p[i] = 0;
+		*pgd_p = (pgdval_t)pud_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE;
+	}
+	pud_p += pud_index(address);
+	pud = *pud_p;
+
+	if (pud)
+		pmd_p = (pmdval_t *)((pud & PTE_PFN_MASK) + __START_KERNEL_map - phys_base);
+	else {
+		if (next_early_pgt >= EARLY_DYNAMIC_PAGE_TABLES) {
+			reset_early_page_tables();
+			goto again;
+		}
+
+		pmd_p = (pmdval_t *)early_dynamic_pgts[next_early_pgt++];
+		for (i = 0; i < PTRS_PER_PMD; i++)
+			pmd_p[i] = 0;
+		*pud_p = (pudval_t)pmd_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE;
+	}
+	pmd = (physaddr & PMD_MASK) + (__PAGE_KERNEL_LARGE & ~_PAGE_GLOBAL);
+	pmd_p[pmd_index(address)] = pmd;
+
+	return 0;
 }
 
 /* Don't add a printk in there. printk relies on the PDA which is not initialized 
@@ -41,13 +112,25 @@ static void __init clear_bss(void)
 	       (unsigned long) __bss_stop - (unsigned long) __bss_start);
 }
 
+static unsigned long get_cmd_line_ptr(void)
+{
+	unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
+
+	cmd_line_ptr |= (u64)boot_params.ext_cmd_line_ptr << 32;
+
+	return cmd_line_ptr;
+}
+
 static void __init copy_bootdata(char *real_mode_data)
 {
 	char * command_line;
+	unsigned long cmd_line_ptr;
 
 	memcpy(&boot_params, real_mode_data, sizeof boot_params);
-	if (boot_params.hdr.cmd_line_ptr) {
-		command_line = __va(boot_params.hdr.cmd_line_ptr);
+	sanitize_boot_params(&boot_params);
+	cmd_line_ptr = get_cmd_line_ptr();
+	if (cmd_line_ptr) {
+		command_line = __va(cmd_line_ptr);
 		memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
 	}
 }
@@ -70,14 +153,12 @@ void __init x86_64_start_kernel(char * real_mode_data)
 				(__START_KERNEL & PGDIR_MASK)));
 	BUILD_BUG_ON(__fix_to_virt(__end_of_fixed_addresses) <= MODULES_END);
 
+	/* Kill off the identity-map trampoline */
+	reset_early_page_tables();
+
 	/* clear bss before set_intr_gate with early_idt_handler */
 	clear_bss();
 
-	/* Make NULL pointers segfault */
-	zap_identity_mappings();
-
-	max_pfn_mapped = KERNEL_IMAGE_SIZE >> PAGE_SHIFT;
-
 	for (i = 0; i < NUM_EXCEPTION_VECTORS; i++) {
 #ifdef CONFIG_EARLY_PRINTK
 		set_intr_gate(i, &early_idt_handlers[i]);
@@ -87,37 +168,25 @@ void __init x86_64_start_kernel(char * real_mode_data)
 	}
 	load_idt((const struct desc_ptr *)&idt_descr);
 
+	copy_bootdata(__va(real_mode_data));
+
 	if (console_loglevel == 10)
 		early_printk("Kernel alive\n");
 
+	clear_page(init_level4_pgt);
+	/* set init_level4_pgt kernel high mapping*/
+	init_level4_pgt[511] = early_level4_pgt[511];
+
 	x86_64_start_reservations(real_mode_data);
 }
 
 void __init x86_64_start_reservations(char *real_mode_data)
 {
-	copy_bootdata(__va(real_mode_data));
-
-	memblock_reserve(__pa_symbol(_text),
-			 (unsigned long)__bss_stop - (unsigned long)_text);
-
-#ifdef CONFIG_BLK_DEV_INITRD
-	/* Reserve INITRD */
-	if (boot_params.hdr.type_of_loader && boot_params.hdr.ramdisk_image) {
-		/* Assume only end is not page aligned */
-		unsigned long ramdisk_image = boot_params.hdr.ramdisk_image;
-		unsigned long ramdisk_size  = boot_params.hdr.ramdisk_size;
-		unsigned long ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
-		memblock_reserve(ramdisk_image, ramdisk_end - ramdisk_image);
-	}
-#endif
+	/* version is always not zero if it is copied */
+	if (!boot_params.hdr.version)
+		copy_bootdata(__va(real_mode_data));
 
 	reserve_ebda_region();
 
-	/*
-	 * At this point everything still needed from the boot loader
-	 * or BIOS or kernel text should be early reserved or marked not
-	 * RAM in e820. All other memory is free game.
-	 */
-
 	start_kernel();
 }

arch/x86/kernel/head_64.S

@@ -47,14 +47,13 @@ L3_START_KERNEL = pud_index(__START_KERNEL_map)
 	.code64
 	.globl startup_64
 startup_64:
-
 	/*
 	 * At this point the CPU runs in 64bit mode CS.L = 1 CS.D = 1,
 	 * and someone has loaded an identity mapped page table
 	 * for us.  These identity mapped page tables map all of the
 	 * kernel pages and possibly all of memory.
 	 *
-	 * %esi holds a physical pointer to real_mode_data.
+	 * %rsi holds a physical pointer to real_mode_data.
 	 *
 	 * We come here either directly from a 64bit bootloader, or from
 	 * arch/x86_64/boot/compressed/head.S.
@@ -66,7 +65,8 @@ startup_64:
 	 * tables and then reload them.
 	 */
 
-	/* Compute the delta between the address I am compiled to run at and the
+	/*
+	 * Compute the delta between the address I am compiled to run at and the
 	 * address I am actually running at.
 	 */
 	leaq	_text(%rip), %rbp
@@ -78,45 +78,62 @@ startup_64:
 	testl	%eax, %eax
 	jnz	bad_address
 
-	/* Is the address too large? */
-	leaq	_text(%rip), %rdx
-	movq	$PGDIR_SIZE, %rax
-	cmpq	%rax, %rdx
-	jae	bad_address
-
-	/* Fixup the physical addresses in the page table
+	/*
+	 * Is the address too large?
 	 */
-	addq	%rbp, init_level4_pgt + 0(%rip)
-	addq	%rbp, init_level4_pgt + (L4_PAGE_OFFSET*8)(%rip)
-	addq	%rbp, init_level4_pgt + (L4_START_KERNEL*8)(%rip)
+	leaq	_text(%rip), %rax
+	shrq	$MAX_PHYSMEM_BITS, %rax
+	jnz	bad_address
 
-	addq	%rbp, level3_ident_pgt + 0(%rip)
+	/*
+	 * Fixup the physical addresses in the page table
+	 */
+	addq	%rbp, early_level4_pgt + (L4_START_KERNEL*8)(%rip)
 
 	addq	%rbp, level3_kernel_pgt + (510*8)(%rip)
 	addq	%rbp, level3_kernel_pgt + (511*8)(%rip)
 
 	addq	%rbp, level2_fixmap_pgt + (506*8)(%rip)
 
-	/* Add an Identity mapping if I am above 1G */
+	/*
+	 * Set up the identity mapping for the switchover.  These
+	 * entries should *NOT* have the global bit set!  This also
+	 * creates a bunch of nonsense entries but that is fine --
+	 * it avoids problems around wraparound.
+	 */
 	leaq	_text(%rip), %rdi
-	andq	$PMD_PAGE_MASK, %rdi
+	leaq	early_level4_pgt(%rip), %rbx
 
 	movq	%rdi, %rax
-	shrq	$PUD_SHIFT, %rax
-	andq	$(PTRS_PER_PUD - 1), %rax
-	jz	ident_complete
+	shrq	$PGDIR_SHIFT, %rax
 
-	leaq	(level2_spare_pgt - __START_KERNEL_map + _KERNPG_TABLE)(%rbp), %rdx
-	leaq	level3_ident_pgt(%rip), %rbx
-	movq	%rdx, 0(%rbx, %rax, 8)
+	leaq	(4096 + _KERNPG_TABLE)(%rbx), %rdx
+	movq	%rdx, 0(%rbx,%rax,8)
+	movq	%rdx, 8(%rbx,%rax,8)
 
+	addq	$4096, %rdx
 	movq	%rdi, %rax
-	shrq	$PMD_SHIFT, %rax
-	andq	$(PTRS_PER_PMD - 1), %rax
-	leaq	__PAGE_KERNEL_IDENT_LARGE_EXEC(%rdi), %rdx
-	leaq	level2_spare_pgt(%rip), %rbx
-	movq	%rdx, 0(%rbx, %rax, 8)
-ident_complete:
+	shrq	$PUD_SHIFT, %rax
+	andl	$(PTRS_PER_PUD-1), %eax
+	movq	%rdx, (4096+0)(%rbx,%rax,8)
+	movq	%rdx, (4096+8)(%rbx,%rax,8)
+
+	addq	$8192, %rbx
+	movq	%rdi, %rax
+	shrq	$PMD_SHIFT, %rdi
+	addq	$(__PAGE_KERNEL_LARGE_EXEC & ~_PAGE_GLOBAL), %rax
+	leaq	(_end - 1)(%rip), %rcx
+	shrq	$PMD_SHIFT, %rcx
+	subq	%rdi, %rcx
+	incl	%ecx
+
+1:
+	andq	$(PTRS_PER_PMD - 1), %rdi
+	movq	%rax, (%rbx,%rdi,8)
+	incq	%rdi
+	addq	$PMD_SIZE, %rax
+	decl	%ecx
+	jnz	1b
 
 	/*
 	 * Fixup the kernel text+data virtual addresses. Note that
@@ -124,7 +141,6 @@ ident_complete:
 	 * cleanup_highmap() fixes this up along with the mappings
 	 * beyond _end.
 	 */
-
 	leaq	level2_kernel_pgt(%rip), %rdi
 	leaq	4096(%rdi), %r8
 	/* See if it is a valid page table entry */
@@ -139,17 +155,14 @@ ident_complete:
 	/* Fixup phys_base */
 	addq	%rbp, phys_base(%rip)
 
-	/* Due to ENTRY(), sometimes the empty space gets filled with
-	 * zeros. Better take a jmp than relying on empty space being
-	 * filled with 0x90 (nop)
-	 */
-	jmp secondary_startup_64
+	movq	$(early_level4_pgt - __START_KERNEL_map), %rax
+	jmp 1f
 ENTRY(secondary_startup_64)
 	/*
 	 * At this point the CPU runs in 64bit mode CS.L = 1 CS.D = 1,
 	 * and someone has loaded a mapped page table.
 	 *
-	 * %esi holds a physical pointer to real_mode_data.
+	 * %rsi holds a physical pointer to real_mode_data.
 	 *
 	 * We come here either from startup_64 (using physical addresses)
 	 * or from trampoline.S (using virtual addresses).
@@ -159,12 +172,14 @@ ENTRY(secondary_startup_64)
 	 * after the boot processor executes this code.
 	 */
 
+	movq	$(init_level4_pgt - __START_KERNEL_map), %rax
+1:
+
 	/* Enable PAE mode and PGE */
-	movl	$(X86_CR4_PAE | X86_CR4_PGE), %eax
-	movq	%rax, %cr4
+	movl	$(X86_CR4_PAE | X86_CR4_PGE), %ecx
+	movq	%rcx, %cr4
 
 	/* Setup early boot stage 4 level pagetables. */
-	movq	$(init_level4_pgt - __START_KERNEL_map), %rax
 	addq	phys_base(%rip), %rax
 	movq	%rax, %cr3
 
@@ -196,7 +211,7 @@ ENTRY(secondary_startup_64)
 	movq	%rax, %cr0
 
 	/* Setup a boot time stack */
-	movq stack_start(%rip),%rsp
+	movq stack_start(%rip), %rsp
 
 	/* zero EFLAGS after setting rsp */
 	pushq $0
@@ -236,15 +251,33 @@ ENTRY(secondary_startup_64)
 	movl	initial_gs+4(%rip),%edx
 	wrmsr	
 
-	/* esi is pointer to real mode structure with interesting info.
+	/* rsi is pointer to real mode structure with interesting info.
 	   pass it to C */
-	movl	%esi, %edi
+	movq	%rsi, %rdi
 	
 	/* Finally jump to run C code and to be on real kernel address
 	 * Since we are running on identity-mapped space we have to jump
 	 * to the full 64bit address, this is only possible as indirect
 	 * jump.  In addition we need to ensure %cs is set so we make this
 	 * a far return.
+	 *
+	 * Note: do not change to far jump indirect with 64bit offset.
+	 *
+	 * AMD does not support far jump indirect with 64bit offset.
+	 * AMD64 Architecture Programmer's Manual, Volume 3: states only
+	 *	JMP FAR mem16:16 FF /5 Far jump indirect,
+	 *		with the target specified by a far pointer in memory.
+	 *	JMP FAR mem16:32 FF /5 Far jump indirect,
+	 *		with the target specified by a far pointer in memory.
+	 *
+	 * Intel64 does support 64bit offset.
+	 * Software Developer Manual Vol 2: states:
+	 *	FF /5 JMP m16:16 Jump far, absolute indirect,
+	 *		address given in m16:16
+	 *	FF /5 JMP m16:32 Jump far, absolute indirect,
+	 *		address given in m16:32.
+	 *	REX.W + FF /5 JMP m16:64 Jump far, absolute indirect,
+	 *		address given in m16:64.
 	 */
 	movq	initial_code(%rip),%rax
 	pushq	$0		# fake return address to stop unwinder
@@ -270,13 +303,13 @@ ENDPROC(start_cpu0)
 
 	/* SMP bootup changes these two */
 	__REFDATA
-	.align	8
-	ENTRY(initial_code)
+	.balign	8
+	GLOBAL(initial_code)
 	.quad	x86_64_start_kernel
-	ENTRY(initial_gs)
+	GLOBAL(initial_gs)
 	.quad	INIT_PER_CPU_VAR(irq_stack_union)
 
-	ENTRY(stack_start)
+	GLOBAL(stack_start)
 	.quad  init_thread_union+THREAD_SIZE-8
 	.word  0
 	__FINITDATA
@@ -284,7 +317,7 @@ ENDPROC(start_cpu0)
 bad_address:
 	jmp bad_address
 
-	.section ".init.text","ax"
+	__INIT
 	.globl early_idt_handlers
 early_idt_handlers:
 	# 104(%rsp) %rflags
@@ -321,14 +354,22 @@ ENTRY(early_idt_handler)
 	pushq %r11		#  0(%rsp)
 
 	cmpl $__KERNEL_CS,96(%rsp)
-	jne 10f
+	jne 11f
+
+	cmpl $14,72(%rsp)	# Page fault?
+	jnz 10f
+	GET_CR2_INTO(%rdi)	# can clobber any volatile register if pv
+	call early_make_pgtable
+	andl %eax,%eax
+	jz 20f			# All good
 
+10:
 	leaq 88(%rsp),%rdi	# Pointer to %rip
 	call early_fixup_exception
 	andl %eax,%eax
 	jnz 20f			# Found an exception entry
 
-10:
+11:
 #ifdef CONFIG_EARLY_PRINTK
 	GET_CR2_INTO(%r9)	# can clobber any volatile register if pv
 	movl 80(%rsp),%r8d	# error code
@@ -350,7 +391,7 @@ ENTRY(early_idt_handler)
 1:	hlt
 	jmp 1b
 
-20:	# Exception table entry found
+20:	# Exception table entry found or page table generated
 	popq %r11
 	popq %r10
 	popq %r9
@@ -364,6 +405,8 @@ ENTRY(early_idt_handler)
 	decl early_recursion_flag(%rip)
 	INTERRUPT_RETURN
 
+	__INITDATA
+
 	.balign 4
 early_recursion_flag:
 	.long 0
@@ -374,11 +417,10 @@ early_idt_msg:
 early_idt_ripmsg:
 	.asciz "RIP %s\n"
 #endif /* CONFIG_EARLY_PRINTK */
-	.previous
 
 #define NEXT_PAGE(name) \
 	.balign	PAGE_SIZE; \
-ENTRY(name)
+GLOBAL(name)
 
 /* Automate the creation of 1 to 1 mapping pmd entries */
 #define PMDS(START, PERM, COUNT)			\
@@ -388,24 +430,37 @@ ENTRY(name)
 	i = i + 1 ;					\
 	.endr
 
+	__INITDATA
+NEXT_PAGE(early_level4_pgt)
+	.fill	511,8,0
+	.quad	level3_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE
+
+NEXT_PAGE(early_dynamic_pgts)
+	.fill	512*EARLY_DYNAMIC_PAGE_TABLES,8,0
+
 	.data
-	/*
-	 * This default setting generates an ident mapping at address 0x100000
-	 * and a mapping for the kernel that precisely maps virtual address
-	 * 0xffffffff80000000 to physical address 0x000000. (always using
-	 * 2Mbyte large pages provided by PAE mode)
-	 */
+
+#ifndef CONFIG_XEN
 NEXT_PAGE(init_level4_pgt)
-	.quad	level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
-	.org	init_level4_pgt + L4_PAGE_OFFSET*8, 0
-	.quad	level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
-	.org	init_level4_pgt + L4_START_KERNEL*8, 0
+	.fill	512,8,0
+#else
+NEXT_PAGE(init_level4_pgt)
+	.quad   level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
+	.org    init_level4_pgt + L4_PAGE_OFFSET*8, 0
+	.quad   level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
+	.org    init_level4_pgt + L4_START_KERNEL*8, 0
 	/* (2^48-(2*1024*1024*1024))/(2^39) = 511 */
-	.quad	level3_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE
+	.quad   level3_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE
 
 NEXT_PAGE(level3_ident_pgt)
 	.quad	level2_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
-	.fill	511,8,0
+	.fill	511, 8, 0
+NEXT_PAGE(level2_ident_pgt)
+	/* Since I easily can, map the first 1G.
+	 * Don't set NX because code runs from these pages.
+	 */
+	PMDS(0, __PAGE_KERNEL_IDENT_LARGE_EXEC, PTRS_PER_PMD)
+#endif
 
 NEXT_PAGE(level3_kernel_pgt)
 	.fill	L3_START_KERNEL,8,0
@@ -413,21 +468,6 @@ NEXT_PAGE(level3_kernel_pgt)
 	.quad	level2_kernel_pgt - __START_KERNEL_map + _KERNPG_TABLE
 	.quad	level2_fixmap_pgt - __START_KERNEL_map + _PAGE_TABLE
 
-NEXT_PAGE(level2_fixmap_pgt)
-	.fill	506,8,0
-	.quad	level1_fixmap_pgt - __START_KERNEL_map + _PAGE_TABLE
-	/* 8MB reserved for vsyscalls + a 2MB hole = 4 + 1 entries */
-	.fill	5,8,0
-
-NEXT_PAGE(level1_fixmap_pgt)
-	.fill	512,8,0
-
-NEXT_PAGE(level2_ident_pgt)
-	/* Since I easily can, map the first 1G.
-	 * Don't set NX because code runs from these pages.
-	 */
-	PMDS(0, __PAGE_KERNEL_IDENT_LARGE_EXEC, PTRS_PER_PMD)
-
 NEXT_PAGE(level2_kernel_pgt)
 	/*
 	 * 512 MB kernel mapping. We spend a full page on this pagetable
@@ -442,11 +482,16 @@ NEXT_PAGE(level2_kernel_pgt)
 	PMDS(0, __PAGE_KERNEL_LARGE_EXEC,
 		KERNEL_IMAGE_SIZE/PMD_SIZE)
 
-NEXT_PAGE(level2_spare_pgt)
-	.fill   512, 8, 0
+NEXT_PAGE(level2_fixmap_pgt)
+	.fill	506,8,0
+	.quad	level1_fixmap_pgt - __START_KERNEL_map + _PAGE_TABLE
+	/* 8MB reserved for vsyscalls + a 2MB hole = 4 + 1 entries */
+	.fill	5,8,0
+
+NEXT_PAGE(level1_fixmap_pgt)
+	.fill	512,8,0
 
 #undef PMDS
-#undef NEXT_PAGE
 
 	.data
 	.align 16
@@ -472,6 +517,5 @@ ENTRY(nmi_idt_table)
 	.skip IDT_ENTRIES * 16
 
 	__PAGE_ALIGNED_BSS
-	.align PAGE_SIZE
-ENTRY(empty_zero_page)
+NEXT_PAGE(empty_zero_page)
 	.skip PAGE_SIZE

arch/x86/kernel/machine_kexec_64.c

@@ -16,125 +16,12 @@
 #include <linux/io.h>
 #include <linux/suspend.h>
 
+#include <asm/init.h>
 #include <asm/pgtable.h>
 #include <asm/tlbflush.h>
 #include <asm/mmu_context.h>
 #include <asm/debugreg.h>
 
-static int init_one_level2_page(struct kimage *image, pgd_t *pgd,
-				unsigned long addr)
-{
-	pud_t *pud;
-	pmd_t *pmd;
-	struct page *page;
-	int result = -ENOMEM;
-
-	addr &= PMD_MASK;
-	pgd += pgd_index(addr);
-	if (!pgd_present(*pgd)) {
-		page = kimage_alloc_control_pages(image, 0);
-		if (!page)
-			goto out;
-		pud = (pud_t *)page_address(page);
-		clear_page(pud);
-		set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE));
-	}
-	pud = pud_offset(pgd, addr);
-	if (!pud_present(*pud)) {
-		page = kimage_alloc_control_pages(image, 0);
-		if (!page)
-			goto out;
-		pmd = (pmd_t *)page_address(page);
-		clear_page(pmd);
-		set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
-	}
-	pmd = pmd_offset(pud, addr);
-	if (!pmd_present(*pmd))
-		set_pmd(pmd, __pmd(addr | __PAGE_KERNEL_LARGE_EXEC));
-	result = 0;
-out:
-	return result;
-}
-
-static void init_level2_page(pmd_t *level2p, unsigned long addr)
-{
-	unsigned long end_addr;
-
-	addr &= PAGE_MASK;
-	end_addr = addr + PUD_SIZE;
-	while (addr < end_addr) {
-		set_pmd(level2p++, __pmd(addr | __PAGE_KERNEL_LARGE_EXEC));
-		addr += PMD_SIZE;
-	}
-}
-
-static int init_level3_page(struct kimage *image, pud_t *level3p,
-				unsigned long addr, unsigned long last_addr)
-{
-	unsigned long end_addr;
-	int result;
-
-	result = 0;
-	addr &= PAGE_MASK;
-	end_addr = addr + PGDIR_SIZE;
-	while ((addr < last_addr) && (addr < end_addr)) {
-		struct page *page;
-		pmd_t *level2p;
-
-		page = kimage_alloc_control_pages(image, 0);
-		if (!page) {
-			result = -ENOMEM;
-			goto out;
-		}
-		level2p = (pmd_t *)page_address(page);
-		init_level2_page(level2p, addr);
-		set_pud(level3p++, __pud(__pa(level2p) | _KERNPG_TABLE));
-		addr += PUD_SIZE;
-	}
-	/* clear the unused entries */
-	while (addr < end_addr) {
-		pud_clear(level3p++);
-		addr += PUD_SIZE;
-	}
-out:
-	return result;
-}
-
-
-static int init_level4_page(struct kimage *image, pgd_t *level4p,
-				unsigned long addr, unsigned long last_addr)
-{
-	unsigned long end_addr;
-	int result;
-
-	result = 0;
-	addr &= PAGE_MASK;
-	end_addr = addr + (PTRS_PER_PGD * PGDIR_SIZE);
-	while ((addr < last_addr) && (addr < end_addr)) {
-		struct page *page;
-		pud_t *level3p;
-
-		page = kimage_alloc_control_pages(image, 0);
-		if (!page) {
-			result = -ENOMEM;
-			goto out;
-		}
-		level3p = (pud_t *)page_address(page);
-		result = init_level3_page(image, level3p, addr, last_addr);
-		if (result)
-			goto out;
-		set_pgd(level4p++, __pgd(__pa(level3p) | _KERNPG_TABLE));
-		addr += PGDIR_SIZE;
-	}
-	/* clear the unused entries */
-	while (addr < end_addr) {
-		pgd_clear(level4p++);
-		addr += PGDIR_SIZE;
-	}
-out:
-	return result;
-}
-
 static void free_transition_pgtable(struct kimage *image)
 {
 	free_page((unsigned long)image->arch.pud);
@@ -184,22 +71,62 @@ err:
 	return result;
 }
 
+static void *alloc_pgt_page(void *data)
+{
+	struct kimage *image = (struct kimage *)data;
+	struct page *page;
+	void *p = NULL;
+
+	page = kimage_alloc_control_pages(image, 0);
+	if (page) {
+		p = page_address(page);
+		clear_page(p);
+	}
+
+	return p;
+}
 
 static int init_pgtable(struct kimage *image, unsigned long start_pgtable)
 {
+	struct x86_mapping_info info = {
+		.alloc_pgt_page	= alloc_pgt_page,
+		.context	= image,
+		.pmd_flag	= __PAGE_KERNEL_LARGE_EXEC,
+	};
+	unsigned long mstart, mend;
 	pgd_t *level4p;
 	int result;
+	int i;
+
 	level4p = (pgd_t *)__va(start_pgtable);
-	result = init_level4_page(image, level4p, 0, max_pfn << PAGE_SHIFT);
-	if (result)
-		return result;
+	clear_page(level4p);
+	for (i = 0; i < nr_pfn_mapped; i++) {
+		mstart = pfn_mapped[i].start << PAGE_SHIFT;
+		mend   = pfn_mapped[i].end << PAGE_SHIFT;
+
+		result = kernel_ident_mapping_init(&info,
+						 level4p, mstart, mend);
+		if (result)
+			return result;
+	}
+
 	/*
-	 * image->start may be outside 0 ~ max_pfn, for example when
-	 * jump back to original kernel from kexeced kernel
+	 * segments's mem ranges could be outside 0 ~ max_pfn,
+	 * for example when jump back to original kernel from kexeced kernel.
+	 * or first kernel is booted with user mem map, and second kernel
+	 * could be loaded out of that range.
 	 */
-	result = init_one_level2_page(image, level4p, image->start);
-	if (result)
-		return result;
+	for (i = 0; i < image->nr_segments; i++) {
+		mstart = image->segment[i].mem;
+		mend   = mstart + image->segment[i].memsz;
+
+		result = kernel_ident_mapping_init(&info,
+						 level4p, mstart, mend);
+
+		if (result)
+			return result;
+	}
+
 	return init_transition_pgtable(image, level4p);
 }
 

arch/x86/kernel/setup.c

@@ -108,17 +108,16 @@
 #include <asm/topology.h>
 #include <asm/apicdef.h>
 #include <asm/amd_nb.h>
-#ifdef CONFIG_X86_64
-#include <asm/numa_64.h>
-#endif
 #include <asm/mce.h>
 #include <asm/alternative.h>
 #include <asm/prom.h>
 
 /*
- * end_pfn only includes RAM, while max_pfn_mapped includes all e820 entries.
- * The direct mapping extends to max_pfn_mapped, so that we can directly access
- * apertures, ACPI and other tables without having to play with fixmaps.
+ * max_low_pfn_mapped: highest direct mapped pfn under 4GB
+ * max_pfn_mapped:     highest direct mapped pfn over 4GB
+ *
+ * The direct mapping only covers E820_RAM regions, so the ranges and gaps are
+ * represented by pfn_mapped
  */
 unsigned long max_low_pfn_mapped;
 unsigned long max_pfn_mapped;
@@ -276,18 +275,7 @@ void * __init extend_brk(size_t size, size_t align)
 	return ret;
 }
 
-#ifdef CONFIG_X86_64
-static void __init init_gbpages(void)
-{
-	if (direct_gbpages && cpu_has_gbpages)
-		printk(KERN_INFO "Using GB pages for direct mapping\n");
-	else
-		direct_gbpages = 0;
-}
-#else
-static inline void init_gbpages(void)
-{
-}
+#ifdef CONFIG_X86_32
 static void __init cleanup_highmap(void)
 {
 }
@@ -306,27 +294,43 @@ static void __init reserve_brk(void)
 
 #ifdef CONFIG_BLK_DEV_INITRD
 
+static u64 __init get_ramdisk_image(void)
+{
+	u64 ramdisk_image = boot_params.hdr.ramdisk_image;
+
+	ramdisk_image |= (u64)boot_params.ext_ramdisk_image << 32;
+
+	return ramdisk_image;
+}
+static u64 __init get_ramdisk_size(void)
+{
+	u64 ramdisk_size = boot_params.hdr.ramdisk_size;
+
+	ramdisk_size |= (u64)boot_params.ext_ramdisk_size << 32;
+
+	return ramdisk_size;
+}
+
 #define MAX_MAP_CHUNK	(NR_FIX_BTMAPS << PAGE_SHIFT)
 static void __init relocate_initrd(void)
 {
 	/* Assume only end is not page aligned */
-	u64 ramdisk_image = boot_params.hdr.ramdisk_image;
-	u64 ramdisk_size  = boot_params.hdr.ramdisk_size;
+	u64 ramdisk_image = get_ramdisk_image();
+	u64 ramdisk_size  = get_ramdisk_size();
 	u64 area_size     = PAGE_ALIGN(ramdisk_size);
-	u64 end_of_lowmem = max_low_pfn_mapped << PAGE_SHIFT;
 	u64 ramdisk_here;
 	unsigned long slop, clen, mapaddr;
 	char *p, *q;
 
-	/* We need to move the initrd down into lowmem */
-	ramdisk_here = memblock_find_in_range(0, end_of_lowmem, area_size,
-					 PAGE_SIZE);
+	/* We need to move the initrd down into directly mapped mem */
+	ramdisk_here = memblock_find_in_range(0, PFN_PHYS(max_pfn_mapped),
+						 area_size, PAGE_SIZE);
 
 	if (!ramdisk_here)
 		panic("Cannot find place for new RAMDISK of size %lld\n",
 			 ramdisk_size);
 
-	/* Note: this includes all the lowmem currently occupied by
+	/* Note: this includes all the mem currently occupied by
 	   the initrd, we rely on that fact to keep the data intact. */
 	memblock_reserve(ramdisk_here, area_size);
 	initrd_start = ramdisk_here + PAGE_OFFSET;
@@ -336,17 +340,7 @@ static void __init relocate_initrd(void)
 
 	q = (char *)initrd_start;
 
-	/* Copy any lowmem portion of the initrd */
-	if (ramdisk_image < end_of_lowmem) {
-		clen = end_of_lowmem - ramdisk_image;
-		p = (char *)__va(ramdisk_image);
-		memcpy(q, p, clen);
-		q += clen;
-		ramdisk_image += clen;
-		ramdisk_size  -= clen;
-	}
-
-	/* Copy the highmem portion of the initrd */
+	/* Copy the initrd */
 	while (ramdisk_size) {
 		slop = ramdisk_image & ~PAGE_MASK;
 		clen = ramdisk_size;
@@ -360,22 +354,35 @@ static void __init relocate_initrd(void)
 		ramdisk_image += clen;
 		ramdisk_size  -= clen;
 	}
-	/* high pages is not converted by early_res_to_bootmem */
-	ramdisk_image = boot_params.hdr.ramdisk_image;
-	ramdisk_size  = boot_params.hdr.ramdisk_size;
+
+	ramdisk_image = get_ramdisk_image();
+	ramdisk_size  = get_ramdisk_size();
 	printk(KERN_INFO "Move RAMDISK from [mem %#010llx-%#010llx] to"
 		" [mem %#010llx-%#010llx]\n",
 		ramdisk_image, ramdisk_image + ramdisk_size - 1,
 		ramdisk_here, ramdisk_here + ramdisk_size - 1);
 }
 
+static void __init early_reserve_initrd(void)
+{
+	/* Assume only end is not page aligned */
+	u64 ramdisk_image = get_ramdisk_image();
+	u64 ramdisk_size  = get_ramdisk_size();
+	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
+
+	if (!boot_params.hdr.type_of_loader ||
+	    !ramdisk_image || !ramdisk_size)
+		return;		/* No initrd provided by bootloader */
+
+	memblock_reserve(ramdisk_image, ramdisk_end - ramdisk_image);
+}
 static void __init reserve_initrd(void)
 {
 	/* Assume only end is not page aligned */
-	u64 ramdisk_image = boot_params.hdr.ramdisk_image;
-	u64 ramdisk_size  = boot_params.hdr.ramdisk_size;
+	u64 ramdisk_image = get_ramdisk_image();
+	u64 ramdisk_size  = get_ramdisk_size();
 	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
-	u64 end_of_lowmem = max_low_pfn_mapped << PAGE_SHIFT;
+	u64 mapped_size;
 
 	if (!boot_params.hdr.type_of_loader ||
 	    !ramdisk_image || !ramdisk_size)
@@ -383,22 +390,18 @@ static void __init reserve_initrd(void)
 
 	initrd_start = 0;
 
-	if (ramdisk_size >= (end_of_lowmem>>1)) {
+	mapped_size = memblock_mem_size(max_pfn_mapped);
+	if (ramdisk_size >= (mapped_size>>1))
 		panic("initrd too large to handle, "
 		       "disabling initrd (%lld needed, %lld available)\n",
-		       ramdisk_size, end_of_lowmem>>1);
-	}
+		       ramdisk_size, mapped_size>>1);
 
 	printk(KERN_INFO "RAMDISK: [mem %#010llx-%#010llx]\n", ramdisk_image,
 			ramdisk_end - 1);
 
-
-	if (ramdisk_end <= end_of_lowmem) {
-		/* All in lowmem, easy case */
-		/*
-		 * don't need to reserve again, already reserved early
-		 * in i386_start_kernel
-		 */
+	if (pfn_range_is_mapped(PFN_DOWN(ramdisk_image),
+				PFN_DOWN(ramdisk_end))) {
+		/* All are mapped, easy case */
 		initrd_start = ramdisk_image + PAGE_OFFSET;
 		initrd_end = initrd_start + ramdisk_size;
 		return;
@@ -409,6 +412,9 @@ static void __init reserve_initrd(void)
 	memblock_free(ramdisk_image, ramdisk_end - ramdisk_image);
 }
 #else
+static void __init early_reserve_initrd(void)
+{
+}
 static void __init reserve_initrd(void)
 {
 }
@@ -419,8 +425,6 @@ static void __init parse_setup_data(void)
 	struct setup_data *data;
 	u64 pa_data;
 
-	if (boot_params.hdr.version < 0x0209)
-		return;
 	pa_data = boot_params.hdr.setup_data;
 	while (pa_data) {
 		u32 data_len, map_len;
@@ -456,8 +460,6 @@ static void __init e820_reserve_setup_data(void)
 	u64 pa_data;
 	int found = 0;
 
-	if (boot_params.hdr.version < 0x0209)
-		return;
 	pa_data = boot_params.hdr.setup_data;
 	while (pa_data) {
 		data = early_memremap(pa_data, sizeof(*data));
@@ -481,8 +483,6 @@ static void __init memblock_x86_reserve_range_setup_data(void)
 	struct setup_data *data;
 	u64 pa_data;
 
-	if (boot_params.hdr.version < 0x0209)
-		return;
 	pa_data = boot_params.hdr.setup_data;
 	while (pa_data) {
 		data = early_memremap(pa_data, sizeof(*data));
@@ -501,17 +501,51 @@ static void __init memblock_x86_reserve_range_setup_data(void)
 /*
  * Keep the crash kernel below this limit.  On 32 bits earlier kernels
  * would limit the kernel to the low 512 MiB due to mapping restrictions.
- * On 64 bits, kexec-tools currently limits us to 896 MiB; increase this
- * limit once kexec-tools are fixed.
  */
 #ifdef CONFIG_X86_32
 # define CRASH_KERNEL_ADDR_MAX	(512 << 20)
 #else
-# define CRASH_KERNEL_ADDR_MAX	(896 << 20)
+# define CRASH_KERNEL_ADDR_MAX	MAXMEM
 #endif
 
+static void __init reserve_crashkernel_low(void)
+{
+#ifdef CONFIG_X86_64
+	const unsigned long long alignment = 16<<20;	/* 16M */
+	unsigned long long low_base = 0, low_size = 0;
+	unsigned long total_low_mem;
+	unsigned long long base;
+	int ret;
+
+	total_low_mem = memblock_mem_size(1UL<<(32-PAGE_SHIFT));
+	ret = parse_crashkernel_low(boot_command_line, total_low_mem,
+						&low_size, &base);
+	if (ret != 0 || low_size <= 0)
+		return;
+
+	low_base = memblock_find_in_range(low_size, (1ULL<<32),
+					low_size, alignment);
+
+	if (!low_base) {
+		pr_info("crashkernel low reservation failed - No suitable area found.\n");
+
+		return;
+	}
+
+	memblock_reserve(low_base, low_size);
+	pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (System low RAM: %ldMB)\n",
+			(unsigned long)(low_size >> 20),
+			(unsigned long)(low_base >> 20),
+			(unsigned long)(total_low_mem >> 20));
+	crashk_low_res.start = low_base;
+	crashk_low_res.end   = low_base + low_size - 1;
+	insert_resource(&iomem_resource, &crashk_low_res);
+#endif
+}
+
 static void __init reserve_crashkernel(void)
 {
+	const unsigned long long alignment = 16<<20;	/* 16M */
 	unsigned long long total_mem;
 	unsigned long long crash_size, crash_base;
 	int ret;
@@ -525,8 +559,6 @@ static void __init reserve_crashkernel(void)
 
 	/* 0 means: find the address automatically */
 	if (crash_base <= 0) {
-		const unsigned long long alignment = 16<<20;	/* 16M */
-
 		/*
 		 *  kexec want bzImage is below CRASH_KERNEL_ADDR_MAX
 		 */
@@ -537,6 +569,7 @@ static void __init reserve_crashkernel(void)
 			pr_info("crashkernel reservation failed - No suitable area found.\n");
 			return;
 		}
+
 	} else {
 		unsigned long long start;
 
@@ -558,6 +591,9 @@ static void __init reserve_crashkernel(void)
 	crashk_res.start = crash_base;
 	crashk_res.end   = crash_base + crash_size - 1;
 	insert_resource(&iomem_resource, &crashk_res);
+
+	if (crash_base >= (1ULL<<32))
+		reserve_crashkernel_low();
 }
 #else
 static void __init reserve_crashkernel(void)
@@ -708,6 +744,27 @@ static void __init trim_bios_range(void)
 	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 }
 
+/* called before trim_bios_range() to spare extra sanitize */
+static void __init e820_add_kernel_range(void)
+{
+	u64 start = __pa_symbol(_text);
+	u64 size = __pa_symbol(_end) - start;
+
+	/*
+	 * Complain if .text .data and .bss are not marked as E820_RAM and
+	 * attempt to fix it by adding the range. We may have a confused BIOS,
+	 * or the user may have used memmap=exactmap or memmap=xxM$yyM to
+	 * exclude kernel range. If we really are running on top non-RAM,
+	 * we will crash later anyways.
+	 */
+	if (e820_all_mapped(start, start + size, E820_RAM))
+		return;
+
+	pr_warn(".text .data .bss are not marked as E820_RAM!\n");
+	e820_remove_range(start, size, E820_RAM, 0);
+	e820_add_region(start, size, E820_RAM);
+}
+
 static unsigned reserve_low = CONFIG_X86_RESERVE_LOW << 10;
 
 static int __init parse_reservelow(char *p)
@@ -752,6 +809,17 @@ static void __init trim_low_memory_range(void)
 
 void __init setup_arch(char **cmdline_p)
 {
+	memblock_reserve(__pa_symbol(_text),
+			 (unsigned long)__bss_stop - (unsigned long)_text);
+
+	early_reserve_initrd();
+
+	/*
+	 * At this point everything still needed from the boot loader
+	 * or BIOS or kernel text should be early reserved or marked not
+	 * RAM in e820. All other memory is free game.
+	 */
+
 #ifdef CONFIG_X86_32
 	memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
 	visws_early_detect();
@@ -910,6 +978,7 @@ void __init setup_arch(char **cmdline_p)
 	insert_resource(&iomem_resource, &data_resource);
 	insert_resource(&iomem_resource, &bss_resource);
 
+	e820_add_kernel_range();
 	trim_bios_range();
 #ifdef CONFIG_X86_32
 	if (ppro_with_ram_bug()) {
@@ -959,6 +1028,8 @@ void __init setup_arch(char **cmdline_p)
 
 	reserve_ibft_region();
 
+	early_alloc_pgt_buf();
+
 	/*
 	 * Need to conclude brk, before memblock_x86_fill()
 	 *  it could use memblock_find_in_range, could overlap with
@@ -968,7 +1039,7 @@ void __init setup_arch(char **cmdline_p)
 
 	cleanup_highmap();
 
-	memblock.current_limit = get_max_mapped();
+	memblock.current_limit = ISA_END_ADDRESS;
 	memblock_x86_fill();
 
 	/*
@@ -985,42 +1056,22 @@ void __init setup_arch(char **cmdline_p)
 	setup_bios_corruption_check();
 #endif
 
+#ifdef CONFIG_X86_32
 	printk(KERN_DEBUG "initial memory mapped: [mem 0x00000000-%#010lx]\n",
 			(max_pfn_mapped<<PAGE_SHIFT) - 1);
+#endif
 
-	setup_real_mode();
+	reserve_real_mode();
 
 	trim_platform_memory_ranges();
 	trim_low_memory_range();
 
-	init_gbpages();
-
-	/* max_pfn_mapped is updated here */
-	max_low_pfn_mapped = init_memory_mapping(0, max_low_pfn<<PAGE_SHIFT);
-	max_pfn_mapped = max_low_pfn_mapped;
-
-#ifdef CONFIG_X86_64
-	if (max_pfn > max_low_pfn) {
-		int i;
-		unsigned long start, end;
-		unsigned long start_pfn, end_pfn;
-
-		for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn,
-							 NULL) {
+	init_mem_mapping();
 
-			end = PFN_PHYS(end_pfn);
-			if (end <= (1UL<<32))
-				continue;
+	early_trap_pf_init();
 
-			start = PFN_PHYS(start_pfn);
-			max_pfn_mapped = init_memory_mapping(
-						max((1UL<<32), start), end);
-		}
+	setup_real_mode();
 
-		/* can we preseve max_low_pfn ?*/
-		max_low_pfn = max_pfn;
-	}
-#endif
 	memblock.current_limit = get_max_mapped();
 	dma_contiguous_reserve(0);
 

arch/x86/kernel/traps.c

@@ -688,10 +688,19 @@ void __init early_trap_init(void)
 	set_intr_gate_ist(X86_TRAP_DB, &debug, DEBUG_STACK);
 	/* int3 can be called from all */
 	set_system_intr_gate_ist(X86_TRAP_BP, &int3, DEBUG_STACK);
+#ifdef CONFIG_X86_32
 	set_intr_gate(X86_TRAP_PF, &page_fault);
+#endif
 	load_idt(&idt_descr);
 }
 
+void __init early_trap_pf_init(void)
+{
+#ifdef CONFIG_X86_64
+	set_intr_gate(X86_TRAP_PF, &page_fault);
+#endif
+}
+
 void __init trap_init(void)
 {
 	int i;

arch/x86/kernel/x86_init.c

@@ -62,10 +62,6 @@ struct x86_init_ops x86_init __initdata = {
 		.banner			= default_banner,
 	},
 
-	.mapping = {
-		.pagetable_reserve		= native_pagetable_reserve,
-	},
-
 	.paging = {
 		.pagetable_init		= native_pagetable_init,
 	},

arch/x86/mm/init.c

@@ -17,86 +17,132 @@
 #include <asm/proto.h>
 #include <asm/dma.h>		/* for MAX_DMA_PFN */
 
-unsigned long __initdata pgt_buf_start;
-unsigned long __meminitdata pgt_buf_end;
-unsigned long __meminitdata pgt_buf_top;
+#include "mm_internal.h"
 
-int after_bootmem;
+static unsigned long __initdata pgt_buf_start;
+static unsigned long __initdata pgt_buf_end;
+static unsigned long __initdata pgt_buf_top;
 
-int direct_gbpages
-#ifdef CONFIG_DIRECT_GBPAGES
-				= 1
-#endif
-;
+static unsigned long min_pfn_mapped;
 
-struct map_range {
-	unsigned long start;
-	unsigned long end;
-	unsigned page_size_mask;
-};
+static bool __initdata can_use_brk_pgt = true;
 
 /*
- * First calculate space needed for kernel direct mapping page tables to cover
- * mr[0].start to mr[nr_range - 1].end, while accounting for possible 2M and 1GB
- * pages. Then find enough contiguous space for those page tables.
+ * Pages returned are already directly mapped.
+ *
+ * Changing that is likely to break Xen, see commit:
+ *
+ *    279b706 x86,xen: introduce x86_init.mapping.pagetable_reserve
+ *
+ * for detailed information.
  */
-static void __init find_early_table_space(struct map_range *mr, int nr_range)
+__ref void *alloc_low_pages(unsigned int num)
 {
+	unsigned long pfn;
 	int i;
-	unsigned long puds = 0, pmds = 0, ptes = 0, tables;
-	unsigned long start = 0, good_end;
-	phys_addr_t base;
 
-	for (i = 0; i < nr_range; i++) {
-		unsigned long range, extra;
+	if (after_bootmem) {
+		unsigned int order;
 
-		range = mr[i].end - mr[i].start;
-		puds += (range + PUD_SIZE - 1) >> PUD_SHIFT;
+		order = get_order((unsigned long)num << PAGE_SHIFT);
+		return (void *)__get_free_pages(GFP_ATOMIC | __GFP_NOTRACK |
+						__GFP_ZERO, order);
+	}
 
-		if (mr[i].page_size_mask & (1 << PG_LEVEL_1G)) {
-			extra = range - ((range >> PUD_SHIFT) << PUD_SHIFT);
-			pmds += (extra + PMD_SIZE - 1) >> PMD_SHIFT;
-		} else {
-			pmds += (range + PMD_SIZE - 1) >> PMD_SHIFT;
-		}
+	if ((pgt_buf_end + num) > pgt_buf_top || !can_use_brk_pgt) {
+		unsigned long ret;
+		if (min_pfn_mapped >= max_pfn_mapped)
+			panic("alloc_low_page: ran out of memory");
+		ret = memblock_find_in_range(min_pfn_mapped << PAGE_SHIFT,
+					max_pfn_mapped << PAGE_SHIFT,
+					PAGE_SIZE * num , PAGE_SIZE);
+		if (!ret)
+			panic("alloc_low_page: can not alloc memory");
+		memblock_reserve(ret, PAGE_SIZE * num);
+		pfn = ret >> PAGE_SHIFT;
+	} else {
+		pfn = pgt_buf_end;
+		pgt_buf_end += num;
+		printk(KERN_DEBUG "BRK [%#010lx, %#010lx] PGTABLE\n",
+			pfn << PAGE_SHIFT, (pgt_buf_end << PAGE_SHIFT) - 1);
+	}
 
-		if (mr[i].page_size_mask & (1 << PG_LEVEL_2M)) {
-			extra = range - ((range >> PMD_SHIFT) << PMD_SHIFT);
-#ifdef CONFIG_X86_32
-			extra += PMD_SIZE;
-#endif
-			ptes += (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
-		} else {
-			ptes += (range + PAGE_SIZE - 1) >> PAGE_SHIFT;
-		}
+	for (i = 0; i < num; i++) {
+		void *adr;
+
+		adr = __va((pfn + i) << PAGE_SHIFT);
+		clear_page(adr);
 	}
 
-	tables = roundup(puds * sizeof(pud_t), PAGE_SIZE);
-	tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE);
-	tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);
+	return __va(pfn << PAGE_SHIFT);
+}
 
-#ifdef CONFIG_X86_32
-	/* for fixmap */
-	tables += roundup(__end_of_fixed_addresses * sizeof(pte_t), PAGE_SIZE);
-#endif
-	good_end = max_pfn_mapped << PAGE_SHIFT;
+/* need 4 4k for initial PMD_SIZE, 4k for 0-ISA_END_ADDRESS */
+#define INIT_PGT_BUF_SIZE	(5 * PAGE_SIZE)
+RESERVE_BRK(early_pgt_alloc, INIT_PGT_BUF_SIZE);
+void  __init early_alloc_pgt_buf(void)
+{
+	unsigned long tables = INIT_PGT_BUF_SIZE;
+	phys_addr_t base;
 
-	base = memblock_find_in_range(start, good_end, tables, PAGE_SIZE);
-	if (!base)
-		panic("Cannot find space for the kernel page tables");
+	base = __pa(extend_brk(tables, PAGE_SIZE));
 
 	pgt_buf_start = base >> PAGE_SHIFT;
 	pgt_buf_end = pgt_buf_start;
 	pgt_buf_top = pgt_buf_start + (tables >> PAGE_SHIFT);
+}
+
+int after_bootmem;
+
+int direct_gbpages
+#ifdef CONFIG_DIRECT_GBPAGES
+				= 1
+#endif
+;
 
-	printk(KERN_DEBUG "kernel direct mapping tables up to %#lx @ [mem %#010lx-%#010lx]\n",
-		mr[nr_range - 1].end - 1, pgt_buf_start << PAGE_SHIFT,
-		(pgt_buf_top << PAGE_SHIFT) - 1);
+static void __init init_gbpages(void)
+{
+#ifdef CONFIG_X86_64
+	if (direct_gbpages && cpu_has_gbpages)
+		printk(KERN_INFO "Using GB pages for direct mapping\n");
+	else
+		direct_gbpages = 0;
+#endif
 }
 
-void __init native_pagetable_reserve(u64 start, u64 end)
+struct map_range {
+	unsigned long start;
+	unsigned long end;
+	unsigned page_size_mask;
+};
+
+static int page_size_mask;
+
+static void __init probe_page_size_mask(void)
 {
-	memblock_reserve(start, end - start);
+	init_gbpages();
+
+#if !defined(CONFIG_DEBUG_PAGEALLOC) && !defined(CONFIG_KMEMCHECK)
+	/*
+	 * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
+	 * This will simplify cpa(), which otherwise needs to support splitting
+	 * large pages into small in interrupt context, etc.
+	 */
+	if (direct_gbpages)
+		page_size_mask |= 1 << PG_LEVEL_1G;
+	if (cpu_has_pse)
+		page_size_mask |= 1 << PG_LEVEL_2M;
+#endif
+
+	/* Enable PSE if available */
+	if (cpu_has_pse)
+		set_in_cr4(X86_CR4_PSE);
+
+	/* Enable PGE if available */
+	if (cpu_has_pge) {
+		set_in_cr4(X86_CR4_PGE);
+		__supported_pte_mask |= _PAGE_GLOBAL;
+	}
 }
 
 #ifdef CONFIG_X86_32
@@ -122,58 +168,51 @@ static int __meminit save_mr(struct map_range *mr, int nr_range,
 }
 
 /*
- * Setup the direct mapping of the physical memory at PAGE_OFFSET.
- * This runs before bootmem is initialized and gets pages directly from
- * the physical memory. To access them they are temporarily mapped.
+ * adjust the page_size_mask for small range to go with
+ *	big page size instead small one if nearby are ram too.
  */
-unsigned long __init_refok init_memory_mapping(unsigned long start,
-					       unsigned long end)
+static void __init_refok adjust_range_page_size_mask(struct map_range *mr,
+							 int nr_range)
 {
-	unsigned long page_size_mask = 0;
-	unsigned long start_pfn, end_pfn;
-	unsigned long ret = 0;
-	unsigned long pos;
-
-	struct map_range mr[NR_RANGE_MR];
-	int nr_range, i;
-	int use_pse, use_gbpages;
+	int i;
 
-	printk(KERN_INFO "init_memory_mapping: [mem %#010lx-%#010lx]\n",
-	       start, end - 1);
+	for (i = 0; i < nr_range; i++) {
+		if ((page_size_mask & (1<<PG_LEVEL_2M)) &&
+		    !(mr[i].page_size_mask & (1<<PG_LEVEL_2M))) {
+			unsigned long start = round_down(mr[i].start, PMD_SIZE);
+			unsigned long end = round_up(mr[i].end, PMD_SIZE);
 
-#if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_KMEMCHECK)
-	/*
-	 * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
-	 * This will simplify cpa(), which otherwise needs to support splitting
-	 * large pages into small in interrupt context, etc.
-	 */
-	use_pse = use_gbpages = 0;
-#else
-	use_pse = cpu_has_pse;
-	use_gbpages = direct_gbpages;
+#ifdef CONFIG_X86_32
+			if ((end >> PAGE_SHIFT) > max_low_pfn)
+				continue;
 #endif
 
-	/* Enable PSE if available */
-	if (cpu_has_pse)
-		set_in_cr4(X86_CR4_PSE);
+			if (memblock_is_region_memory(start, end - start))
+				mr[i].page_size_mask |= 1<<PG_LEVEL_2M;
+		}
+		if ((page_size_mask & (1<<PG_LEVEL_1G)) &&
+		    !(mr[i].page_size_mask & (1<<PG_LEVEL_1G))) {
+			unsigned long start = round_down(mr[i].start, PUD_SIZE);
+			unsigned long end = round_up(mr[i].end, PUD_SIZE);
 
-	/* Enable PGE if available */
-	if (cpu_has_pge) {
-		set_in_cr4(X86_CR4_PGE);
-		__supported_pte_mask |= _PAGE_GLOBAL;
+			if (memblock_is_region_memory(start, end - start))
+				mr[i].page_size_mask |= 1<<PG_LEVEL_1G;
+		}
 	}
+}
 
-	if (use_gbpages)
-		page_size_mask |= 1 << PG_LEVEL_1G;
-	if (use_pse)
-		page_size_mask |= 1 << PG_LEVEL_2M;
+static int __meminit split_mem_range(struct map_range *mr, int nr_range,
+				     unsigned long start,
+				     unsigned long end)
+{
+	unsigned long start_pfn, end_pfn, limit_pfn;
+	unsigned long pfn;
+	int i;
 
-	memset(mr, 0, sizeof(mr));
-	nr_range = 0;
+	limit_pfn = PFN_DOWN(end);
 
 	/* head if not big page alignment ? */
-	start_pfn = start >> PAGE_SHIFT;
-	pos = start_pfn << PAGE_SHIFT;
+	pfn = start_pfn = PFN_DOWN(start);
 #ifdef CONFIG_X86_32
 	/*
 	 * Don't use a large page for the first 2/4MB of memory
@@ -181,66 +220,60 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
 	 * and overlapping MTRRs into large pages can cause
 	 * slowdowns.
 	 */
-	if (pos == 0)
-		end_pfn = 1<<(PMD_SHIFT - PAGE_SHIFT);
+	if (pfn == 0)
+		end_pfn = PFN_DOWN(PMD_SIZE);
 	else
-		end_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
-				 << (PMD_SHIFT - PAGE_SHIFT);
+		end_pfn = round_up(pfn, PFN_DOWN(PMD_SIZE));
 #else /* CONFIG_X86_64 */
-	end_pfn = ((pos + (PMD_SIZE - 1)) >> PMD_SHIFT)
-			<< (PMD_SHIFT - PAGE_SHIFT);
+	end_pfn = round_up(pfn, PFN_DOWN(PMD_SIZE));
 #endif
-	if (end_pfn > (end >> PAGE_SHIFT))
-		end_pfn = end >> PAGE_SHIFT;
+	if (end_pfn > limit_pfn)
+		end_pfn = limit_pfn;
 	if (start_pfn < end_pfn) {
 		nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
-		pos = end_pfn << PAGE_SHIFT;
+		pfn = end_pfn;
 	}
 
 	/* big page (2M) range */
-	start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
-			 << (PMD_SHIFT - PAGE_SHIFT);
+	start_pfn = round_up(pfn, PFN_DOWN(PMD_SIZE));
 #ifdef CONFIG_X86_32
-	end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
+	end_pfn = round_down(limit_pfn, PFN_DOWN(PMD_SIZE));
 #else /* CONFIG_X86_64 */
-	end_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
-			 << (PUD_SHIFT - PAGE_SHIFT);
-	if (end_pfn > ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT)))
-		end_pfn = ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT));
+	end_pfn = round_up(pfn, PFN_DOWN(PUD_SIZE));
+	if (end_pfn > round_down(limit_pfn, PFN_DOWN(PMD_SIZE)))
+		end_pfn = round_down(limit_pfn, PFN_DOWN(PMD_SIZE));
 #endif
 
 	if (start_pfn < end_pfn) {
 		nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
 				page_size_mask & (1<<PG_LEVEL_2M));
-		pos = end_pfn << PAGE_SHIFT;
+		pfn = end_pfn;
 	}
 
 #ifdef CONFIG_X86_64
 	/* big page (1G) range */
-	start_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
-			 << (PUD_SHIFT - PAGE_SHIFT);
-	end_pfn = (end >> PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT);
+	start_pfn = round_up(pfn, PFN_DOWN(PUD_SIZE));
+	end_pfn = round_down(limit_pfn, PFN_DOWN(PUD_SIZE));
 	if (start_pfn < end_pfn) {
 		nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
 				page_size_mask &
 				 ((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G)));
-		pos = end_pfn << PAGE_SHIFT;
+		pfn = end_pfn;
 	}
 
 	/* tail is not big page (1G) alignment */
-	start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
-			 << (PMD_SHIFT - PAGE_SHIFT);
-	end_pfn = (end >> PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
+	start_pfn = round_up(pfn, PFN_DOWN(PMD_SIZE));
+	end_pfn = round_down(limit_pfn, PFN_DOWN(PMD_SIZE));
 	if (start_pfn < end_pfn) {
 		nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
 				page_size_mask & (1<<PG_LEVEL_2M));
-		pos = end_pfn << PAGE_SHIFT;
+		pfn = end_pfn;
 	}
 #endif
 
 	/* tail is not big page (2M) alignment */
-	start_pfn = pos>>PAGE_SHIFT;
-	end_pfn = end>>PAGE_SHIFT;
+	start_pfn = pfn;
+	end_pfn = limit_pfn;
 	nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
 
 	/* try to merge same page size and continuous */
@@ -257,59 +290,169 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
 		nr_range--;
 	}
 
+	if (!after_bootmem)
+		adjust_range_page_size_mask(mr, nr_range);
+
 	for (i = 0; i < nr_range; i++)
 		printk(KERN_DEBUG " [mem %#010lx-%#010lx] page %s\n",
 				mr[i].start, mr[i].end - 1,
 			(mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
 			 (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));
 
-	/*
-	 * Find space for the kernel direct mapping tables.
-	 *
-	 * Later we should allocate these tables in the local node of the
-	 * memory mapped. Unfortunately this is done currently before the
-	 * nodes are discovered.
-	 */
-	if (!after_bootmem)
-		find_early_table_space(mr, nr_range);
+	return nr_range;
+}
+
+struct range pfn_mapped[E820_X_MAX];
+int nr_pfn_mapped;
+
+static void add_pfn_range_mapped(unsigned long start_pfn, unsigned long end_pfn)
+{
+	nr_pfn_mapped = add_range_with_merge(pfn_mapped, E820_X_MAX,
+					     nr_pfn_mapped, start_pfn, end_pfn);
+	nr_pfn_mapped = clean_sort_range(pfn_mapped, E820_X_MAX);
+
+	max_pfn_mapped = max(max_pfn_mapped, end_pfn);
+
+	if (start_pfn < (1UL<<(32-PAGE_SHIFT)))
+		max_low_pfn_mapped = max(max_low_pfn_mapped,
+					 min(end_pfn, 1UL<<(32-PAGE_SHIFT)));
+}
+
+bool pfn_range_is_mapped(unsigned long start_pfn, unsigned long end_pfn)
+{
+	int i;
+
+	for (i = 0; i < nr_pfn_mapped; i++)
+		if ((start_pfn >= pfn_mapped[i].start) &&
+		    (end_pfn <= pfn_mapped[i].end))
+			return true;
+
+	return false;
+}
+
+/*
+ * Setup the direct mapping of the physical memory at PAGE_OFFSET.
+ * This runs before bootmem is initialized and gets pages directly from
+ * the physical memory. To access them they are temporarily mapped.
+ */
+unsigned long __init_refok init_memory_mapping(unsigned long start,
+					       unsigned long end)
+{
+	struct map_range mr[NR_RANGE_MR];
+	unsigned long ret = 0;
+	int nr_range, i;
+
+	pr_info("init_memory_mapping: [mem %#010lx-%#010lx]\n",
+	       start, end - 1);
+
+	memset(mr, 0, sizeof(mr));
+	nr_range = split_mem_range(mr, 0, start, end);
 
 	for (i = 0; i < nr_range; i++)
 		ret = kernel_physical_mapping_init(mr[i].start, mr[i].end,
 						   mr[i].page_size_mask);
 
-#ifdef CONFIG_X86_32
-	early_ioremap_page_table_range_init();
+	add_pfn_range_mapped(start >> PAGE_SHIFT, ret >> PAGE_SHIFT);
 
-	load_cr3(swapper_pg_dir);
-#endif
+	return ret >> PAGE_SHIFT;
+}
 
-	__flush_tlb_all();
+/*
+ * would have hole in the middle or ends, and only ram parts will be mapped.
+ */
+static unsigned long __init init_range_memory_mapping(
+					   unsigned long r_start,
+					   unsigned long r_end)
+{
+	unsigned long start_pfn, end_pfn;
+	unsigned long mapped_ram_size = 0;
+	int i;
 
-	/*
-	 * Reserve the kernel pagetable pages we used (pgt_buf_start -
-	 * pgt_buf_end) and free the other ones (pgt_buf_end - pgt_buf_top)
-	 * so that they can be reused for other purposes.
-	 *
-	 * On native it just means calling memblock_reserve, on Xen it also
-	 * means marking RW the pagetable pages that we allocated before
-	 * but that haven't been used.
-	 *
-	 * In fact on xen we mark RO the whole range pgt_buf_start -
-	 * pgt_buf_top, because we have to make sure that when
-	 * init_memory_mapping reaches the pagetable pages area, it maps
-	 * RO all the pagetable pages, including the ones that are beyond
-	 * pgt_buf_end at that time.
-	 */
-	if (!after_bootmem && pgt_buf_end > pgt_buf_start)
-		x86_init.mapping.pagetable_reserve(PFN_PHYS(pgt_buf_start),
-				PFN_PHYS(pgt_buf_end));
+	for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, NULL) {
+		u64 start = clamp_val(PFN_PHYS(start_pfn), r_start, r_end);
+		u64 end = clamp_val(PFN_PHYS(end_pfn), r_start, r_end);
+		if (start >= end)
+			continue;
 
-	if (!after_bootmem)
-		early_memtest(start, end);
+		/*
+		 * if it is overlapping with brk pgt, we need to
+		 * alloc pgt buf from memblock instead.
+		 */
+		can_use_brk_pgt = max(start, (u64)pgt_buf_end<<PAGE_SHIFT) >=
+				    min(end, (u64)pgt_buf_top<<PAGE_SHIFT);
+		init_memory_mapping(start, end);
+		mapped_ram_size += end - start;
+		can_use_brk_pgt = true;
+	}
 
-	return ret >> PAGE_SHIFT;
+	return mapped_ram_size;
 }
 
+/* (PUD_SHIFT-PMD_SHIFT)/2 */
+#define STEP_SIZE_SHIFT 5
+void __init init_mem_mapping(void)
+{
+	unsigned long end, real_end, start, last_start;
+	unsigned long step_size;
+	unsigned long addr;
+	unsigned long mapped_ram_size = 0;
+	unsigned long new_mapped_ram_size;
+
+	probe_page_size_mask();
+
+#ifdef CONFIG_X86_64
+	end = max_pfn << PAGE_SHIFT;
+#else
+	end = max_low_pfn << PAGE_SHIFT;
+#endif
+
+	/* the ISA range is always mapped regardless of memory holes */
+	init_memory_mapping(0, ISA_END_ADDRESS);
+
+	/* xen has big range in reserved near end of ram, skip it at first */
+	addr = memblock_find_in_range(ISA_END_ADDRESS, end, PMD_SIZE,
+			 PAGE_SIZE);
+	real_end = addr + PMD_SIZE;
+
+	/* step_size need to be small so pgt_buf from BRK could cover it */
+	step_size = PMD_SIZE;
+	max_pfn_mapped = 0; /* will get exact value next */
+	min_pfn_mapped = real_end >> PAGE_SHIFT;
+	last_start = start = real_end;
+	while (last_start > ISA_END_ADDRESS) {
+		if (last_start > step_size) {
+			start = round_down(last_start - 1, step_size);
+			if (start < ISA_END_ADDRESS)
+				start = ISA_END_ADDRESS;
+		} else
+			start = ISA_END_ADDRESS;
+		new_mapped_ram_size = init_range_memory_mapping(start,
+							last_start);
+		last_start = start;
+		min_pfn_mapped = last_start >> PAGE_SHIFT;
+		/* only increase step_size after big range get mapped */
+		if (new_mapped_ram_size > mapped_ram_size)
+			step_size <<= STEP_SIZE_SHIFT;
+		mapped_ram_size += new_mapped_ram_size;
+	}
+
+	if (real_end < end)
+		init_range_memory_mapping(real_end, end);
+
+#ifdef CONFIG_X86_64
+	if (max_pfn > max_low_pfn) {
+		/* can we preseve max_low_pfn ?*/
+		max_low_pfn = max_pfn;
+	}
+#else
+	early_ioremap_page_table_range_init();
+#endif
+
+	load_cr3(swapper_pg_dir);
+	__flush_tlb_all();
+
+	early_memtest(0, max_pfn_mapped << PAGE_SHIFT);
+}
 
 /*
  * devmem_is_allowed() checks to see if /dev/mem access to a certain address

arch/x86/mm/init_32.c

@@ -53,25 +53,14 @@
 #include <asm/page_types.h>
 #include <asm/init.h>
 
+#include "mm_internal.h"
+
 unsigned long highstart_pfn, highend_pfn;
 
 static noinline int do_test_wp_bit(void);
 
 bool __read_mostly __vmalloc_start_set = false;
 
-static __init void *alloc_low_page(void)
-{
-	unsigned long pfn = pgt_buf_end++;
-	void *adr;
-
-	if (pfn >= pgt_buf_top)
-		panic("alloc_low_page: ran out of memory");
-
-	adr = __va(pfn * PAGE_SIZE);
-	clear_page(adr);
-	return adr;
-}
-
 /*
  * Creates a middle page table and puts a pointer to it in the
  * given global directory entry. This only returns the gd entry
@@ -84,10 +73,7 @@ static pmd_t * __init one_md_table_init(pgd_t *pgd)
 
 #ifdef CONFIG_X86_PAE
 	if (!(pgd_val(*pgd) & _PAGE_PRESENT)) {
-		if (after_bootmem)
-			pmd_table = (pmd_t *)alloc_bootmem_pages(PAGE_SIZE);
-		else
-			pmd_table = (pmd_t *)alloc_low_page();
+		pmd_table = (pmd_t *)alloc_low_page();
 		paravirt_alloc_pmd(&init_mm, __pa(pmd_table) >> PAGE_SHIFT);
 		set_pgd(pgd, __pgd(__pa(pmd_table) | _PAGE_PRESENT));
 		pud = pud_offset(pgd, 0);
@@ -109,17 +95,7 @@ static pmd_t * __init one_md_table_init(pgd_t *pgd)
 static pte_t * __init one_page_table_init(pmd_t *pmd)
 {
 	if (!(pmd_val(*pmd) & _PAGE_PRESENT)) {
-		pte_t *page_table = NULL;
-
-		if (after_bootmem) {
-#if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_KMEMCHECK)
-			page_table = (pte_t *) alloc_bootmem_pages(PAGE_SIZE);
-#endif
-			if (!page_table)
-				page_table =
-				(pte_t *)alloc_bootmem_pages(PAGE_SIZE);
-		} else
-			page_table = (pte_t *)alloc_low_page();
+		pte_t *page_table = (pte_t *)alloc_low_page();
 
 		paravirt_alloc_pte(&init_mm, __pa(page_table) >> PAGE_SHIFT);
 		set_pmd(pmd, __pmd(__pa(page_table) | _PAGE_TABLE));
@@ -146,8 +122,39 @@ pte_t * __init populate_extra_pte(unsigned long vaddr)
 	return one_page_table_init(pmd) + pte_idx;
 }
 
+static unsigned long __init
+page_table_range_init_count(unsigned long start, unsigned long end)
+{
+	unsigned long count = 0;
+#ifdef CONFIG_HIGHMEM
+	int pmd_idx_kmap_begin = fix_to_virt(FIX_KMAP_END) >> PMD_SHIFT;
+	int pmd_idx_kmap_end = fix_to_virt(FIX_KMAP_BEGIN) >> PMD_SHIFT;
+	int pgd_idx, pmd_idx;
+	unsigned long vaddr;
+
+	if (pmd_idx_kmap_begin == pmd_idx_kmap_end)
+		return 0;
+
+	vaddr = start;
+	pgd_idx = pgd_index(vaddr);
+
+	for ( ; (pgd_idx < PTRS_PER_PGD) && (vaddr != end); pgd_idx++) {
+		for (; (pmd_idx < PTRS_PER_PMD) && (vaddr != end);
+							pmd_idx++) {
+			if ((vaddr >> PMD_SHIFT) >= pmd_idx_kmap_begin &&
+			    (vaddr >> PMD_SHIFT) <= pmd_idx_kmap_end)
+				count++;
+			vaddr += PMD_SIZE;
+		}
+		pmd_idx = 0;
+	}
+#endif
+	return count;
+}
+
 static pte_t *__init page_table_kmap_check(pte_t *pte, pmd_t *pmd,
-					   unsigned long vaddr, pte_t *lastpte)
+					   unsigned long vaddr, pte_t *lastpte,
+					   void **adr)
 {
 #ifdef CONFIG_HIGHMEM
 	/*
@@ -161,16 +168,15 @@ static pte_t *__init page_table_kmap_check(pte_t *pte, pmd_t *pmd,
 
 	if (pmd_idx_kmap_begin != pmd_idx_kmap_end
 	    && (vaddr >> PMD_SHIFT) >= pmd_idx_kmap_begin
-	    && (vaddr >> PMD_SHIFT) <= pmd_idx_kmap_end
-	    && ((__pa(pte) >> PAGE_SHIFT) < pgt_buf_start
-		|| (__pa(pte) >> PAGE_SHIFT) >= pgt_buf_end)) {
+	    && (vaddr >> PMD_SHIFT) <= pmd_idx_kmap_end) {
 		pte_t *newpte;
 		int i;
 
 		BUG_ON(after_bootmem);
-		newpte = alloc_low_page();
+		newpte = *adr;
 		for (i = 0; i < PTRS_PER_PTE; i++)
 			set_pte(newpte + i, pte[i]);
+		*adr = (void *)(((unsigned long)(*adr)) + PAGE_SIZE);
 
 		paravirt_alloc_pte(&init_mm, __pa(newpte) >> PAGE_SHIFT);
 		set_pmd(pmd, __pmd(__pa(newpte)|_PAGE_TABLE));
@@ -204,6 +210,11 @@ page_table_range_init(unsigned long start, unsigned long end, pgd_t *pgd_base)
 	pgd_t *pgd;
 	pmd_t *pmd;
 	pte_t *pte = NULL;
+	unsigned long count = page_table_range_init_count(start, end);
+	void *adr = NULL;
+
+	if (count)
+		adr = alloc_low_pages(count);
 
 	vaddr = start;
 	pgd_idx = pgd_index(vaddr);
@@ -216,7 +227,7 @@ page_table_range_init(unsigned long start, unsigned long end, pgd_t *pgd_base)
 		for (; (pmd_idx < PTRS_PER_PMD) && (vaddr != end);
 							pmd++, pmd_idx++) {
 			pte = page_table_kmap_check(one_page_table_init(pmd),
-			                            pmd, vaddr, pte);
+						    pmd, vaddr, pte, &adr);
 
 			vaddr += PMD_SIZE;
 		}
@@ -310,6 +321,7 @@ repeat:
 					__pgprot(PTE_IDENT_ATTR |
 						 _PAGE_PSE);
 
+				pfn &= PMD_MASK >> PAGE_SHIFT;
 				addr2 = (pfn + PTRS_PER_PTE-1) * PAGE_SIZE +
 					PAGE_OFFSET + PAGE_SIZE-1;
 
@@ -455,9 +467,14 @@ void __init native_pagetable_init(void)
 
 	/*
 	 * Remove any mappings which extend past the end of physical
-	 * memory from the boot time page table:
+	 * memory from the boot time page table.
+	 * In virtual address space, we should have at least two pages
+	 * from VMALLOC_END to pkmap or fixmap according to VMALLOC_END
+	 * definition. And max_low_pfn is set to VMALLOC_END physical
+	 * address. If initial memory mapping is doing right job, we
+	 * should have pte used near max_low_pfn or one pmd is not present.
 	 */
-	for (pfn = max_low_pfn + 1; pfn < 1<<(32-PAGE_SHIFT); pfn++) {
+	for (pfn = max_low_pfn; pfn < 1<<(32-PAGE_SHIFT); pfn++) {
 		va = PAGE_OFFSET + (pfn<<PAGE_SHIFT);
 		pgd = base + pgd_index(va);
 		if (!pgd_present(*pgd))
@@ -468,10 +485,19 @@ void __init native_pagetable_init(void)
 		if (!pmd_present(*pmd))
 			break;
 
+		/* should not be large page here */
+		if (pmd_large(*pmd)) {
+			pr_warn("try to clear pte for ram above max_low_pfn: pfn: %lx pmd: %p pmd phys: %lx, but pmd is big page and is not using pte !\n",
+				pfn, pmd, __pa(pmd));
+			BUG_ON(1);
+		}
+
 		pte = pte_offset_kernel(pmd, va);
 		if (!pte_present(*pte))
 			break;
 
+		printk(KERN_DEBUG "clearing pte for ram above max_low_pfn: pfn: %lx pmd: %p pmd phys: %lx pte: %p pte phys: %lx\n",
+				pfn, pmd, __pa(pmd), pte, __pa(pte));
 		pte_clear(NULL, va, pte);
 	}
 	paravirt_alloc_pmd(&init_mm, __pa(base) >> PAGE_SHIFT);
@@ -550,7 +576,7 @@ early_param("highmem", parse_highmem);
  * artificially via the highmem=x boot parameter then create
  * it:
  */
-void __init lowmem_pfn_init(void)
+static void __init lowmem_pfn_init(void)
 {
 	/* max_low_pfn is 0, we already have early_res support */
 	max_low_pfn = max_pfn;
@@ -586,7 +612,7 @@ void __init lowmem_pfn_init(void)
  * We have more RAM than fits into lowmem - we try to put it into
  * highmem, also taking the highmem=x boot parameter into account:
  */
-void __init highmem_pfn_init(void)
+static void __init highmem_pfn_init(void)
 {
 	max_low_pfn = MAXMEM_PFN;
 
@@ -669,8 +695,6 @@ void __init setup_bootmem_allocator(void)
 	printk(KERN_INFO "  mapped low ram: 0 - %08lx\n",
 		 max_pfn_mapped<<PAGE_SHIFT);
 	printk(KERN_INFO "  low ram: 0 - %08lx\n", max_low_pfn<<PAGE_SHIFT);
-
-	after_bootmem = 1;
 }
 
 /*
@@ -753,6 +777,8 @@ void __init mem_init(void)
 		if (page_is_ram(tmp) && PageReserved(pfn_to_page(tmp)))
 			reservedpages++;
 
+	after_bootmem = 1;
+
 	codesize =  (unsigned long) &_etext - (unsigned long) &_text;
 	datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
 	initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;

arch/x86/mm/init_64.c

@@ -54,6 +54,82 @@
 #include <asm/uv/uv.h>
 #include <asm/setup.h>
 
+#include "mm_internal.h"
+
+static void ident_pmd_init(unsigned long pmd_flag, pmd_t *pmd_page,
+			   unsigned long addr, unsigned long end)
+{
+	addr &= PMD_MASK;
+	for (; addr < end; addr += PMD_SIZE) {
+		pmd_t *pmd = pmd_page + pmd_index(addr);
+
+		if (!pmd_present(*pmd))
+			set_pmd(pmd, __pmd(addr | pmd_flag));
+	}
+}
+static int ident_pud_init(struct x86_mapping_info *info, pud_t *pud_page,
+			  unsigned long addr, unsigned long end)
+{
+	unsigned long next;
+
+	for (; addr < end; addr = next) {
+		pud_t *pud = pud_page + pud_index(addr);
+		pmd_t *pmd;
+
+		next = (addr & PUD_MASK) + PUD_SIZE;
+		if (next > end)
+			next = end;
+
+		if (pud_present(*pud)) {
+			pmd = pmd_offset(pud, 0);
+			ident_pmd_init(info->pmd_flag, pmd, addr, next);
+			continue;
+		}
+		pmd = (pmd_t *)info->alloc_pgt_page(info->context);
+		if (!pmd)
+			return -ENOMEM;
+		ident_pmd_init(info->pmd_flag, pmd, addr, next);
+		set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
+	}
+
+	return 0;
+}
+
+int kernel_ident_mapping_init(struct x86_mapping_info *info, pgd_t *pgd_page,
+			      unsigned long addr, unsigned long end)
+{
+	unsigned long next;
+	int result;
+	int off = info->kernel_mapping ? pgd_index(__PAGE_OFFSET) : 0;
+
+	for (; addr < end; addr = next) {
+		pgd_t *pgd = pgd_page + pgd_index(addr) + off;
+		pud_t *pud;
+
+		next = (addr & PGDIR_MASK) + PGDIR_SIZE;
+		if (next > end)
+			next = end;
+
+		if (pgd_present(*pgd)) {
+			pud = pud_offset(pgd, 0);
+			result = ident_pud_init(info, pud, addr, next);
+			if (result)
+				return result;
+			continue;
+		}
+
+		pud = (pud_t *)info->alloc_pgt_page(info->context);
+		if (!pud)
+			return -ENOMEM;
+		result = ident_pud_init(info, pud, addr, next);
+		if (result)
+			return result;
+		set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE));
+	}
+
+	return 0;
+}
+
 static int __init parse_direct_gbpages_off(char *arg)
 {
 	direct_gbpages = 0;
@@ -302,10 +378,18 @@ void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
 void __init cleanup_highmap(void)
 {
 	unsigned long vaddr = __START_KERNEL_map;
-	unsigned long vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT);
+	unsigned long vaddr_end = __START_KERNEL_map + KERNEL_IMAGE_SIZE;
 	unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1;
 	pmd_t *pmd = level2_kernel_pgt;
 
+	/*
+	 * Native path, max_pfn_mapped is not set yet.
+	 * Xen has valid max_pfn_mapped set in
+	 *	arch/x86/xen/mmu.c:xen_setup_kernel_pagetable().
+	 */
+	if (max_pfn_mapped)
+		vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT);
+
 	for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) {
 		if (pmd_none(*pmd))
 			continue;
@@ -314,69 +398,24 @@ void __init cleanup_highmap(void)
 	}
 }
 
-static __ref void *alloc_low_page(unsigned long *phys)
-{
-	unsigned long pfn = pgt_buf_end++;
-	void *adr;
-
-	if (after_bootmem) {
-		adr = (void *)get_zeroed_page(GFP_ATOMIC | __GFP_NOTRACK);
-		*phys = __pa(adr);
-
-		return adr;
-	}
-
-	if (pfn >= pgt_buf_top)
-		panic("alloc_low_page: ran out of memory");
-
-	adr = early_memremap(pfn * PAGE_SIZE, PAGE_SIZE);
-	clear_page(adr);
-	*phys  = pfn * PAGE_SIZE;
-	return adr;
-}
-
-static __ref void *map_low_page(void *virt)
-{
-	void *adr;
-	unsigned long phys, left;
-
-	if (after_bootmem)
-		return virt;
-
-	phys = __pa(virt);
-	left = phys & (PAGE_SIZE - 1);
-	adr = early_memremap(phys & PAGE_MASK, PAGE_SIZE);
-	adr = (void *)(((unsigned long)adr) | left);
-
-	return adr;
-}
-
-static __ref void unmap_low_page(void *adr)
-{
-	if (after_bootmem)
-		return;
-
-	early_iounmap((void *)((unsigned long)adr & PAGE_MASK), PAGE_SIZE);
-}
-
 static unsigned long __meminit
 phys_pte_init(pte_t *pte_page, unsigned long addr, unsigned long end,
 	      pgprot_t prot)
 {
-	unsigned pages = 0;
+	unsigned long pages = 0, next;
 	unsigned long last_map_addr = end;
 	int i;
 
 	pte_t *pte = pte_page + pte_index(addr);
 
-	for(i = pte_index(addr); i < PTRS_PER_PTE; i++, addr += PAGE_SIZE, pte++) {
-
+	for (i = pte_index(addr); i < PTRS_PER_PTE; i++, addr = next, pte++) {
+		next = (addr & PAGE_MASK) + PAGE_SIZE;
 		if (addr >= end) {
-			if (!after_bootmem) {
-				for(; i < PTRS_PER_PTE; i++, pte++)
-					set_pte(pte, __pte(0));
-			}
-			break;
+			if (!after_bootmem &&
+			    !e820_any_mapped(addr & PAGE_MASK, next, E820_RAM) &&
+			    !e820_any_mapped(addr & PAGE_MASK, next, E820_RESERVED_KERN))
+				set_pte(pte, __pte(0));
+			continue;
 		}
 
 		/*
@@ -414,28 +453,25 @@ phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
 	int i = pmd_index(address);
 
 	for (; i < PTRS_PER_PMD; i++, address = next) {
-		unsigned long pte_phys;
 		pmd_t *pmd = pmd_page + pmd_index(address);
 		pte_t *pte;
 		pgprot_t new_prot = prot;
 
+		next = (address & PMD_MASK) + PMD_SIZE;
 		if (address >= end) {
-			if (!after_bootmem) {
-				for (; i < PTRS_PER_PMD; i++, pmd++)
-					set_pmd(pmd, __pmd(0));
-			}
-			break;
+			if (!after_bootmem &&
+			    !e820_any_mapped(address & PMD_MASK, next, E820_RAM) &&
+			    !e820_any_mapped(address & PMD_MASK, next, E820_RESERVED_KERN))
+				set_pmd(pmd, __pmd(0));
+			continue;
 		}
 
-		next = (address & PMD_MASK) + PMD_SIZE;
-
 		if (pmd_val(*pmd)) {
 			if (!pmd_large(*pmd)) {
 				spin_lock(&init_mm.page_table_lock);
-				pte = map_low_page((pte_t *)pmd_page_vaddr(*pmd));
+				pte = (pte_t *)pmd_page_vaddr(*pmd);
 				last_map_addr = phys_pte_init(pte, address,
 								end, prot);
-				unmap_low_page(pte);
 				spin_unlock(&init_mm.page_table_lock);
 				continue;
 			}
@@ -464,19 +500,18 @@ phys_pmd_init(pmd_t *pmd_page, unsigned long address, unsigned long end,
 			pages++;
 			spin_lock(&init_mm.page_table_lock);
 			set_pte((pte_t *)pmd,
-				pfn_pte(address >> PAGE_SHIFT,
+				pfn_pte((address & PMD_MASK) >> PAGE_SHIFT,
 					__pgprot(pgprot_val(prot) | _PAGE_PSE)));
 			spin_unlock(&init_mm.page_table_lock);
 			last_map_addr = next;
 			continue;
 		}
 
-		pte = alloc_low_page(&pte_phys);
+		pte = alloc_low_page();
 		last_map_addr = phys_pte_init(pte, address, end, new_prot);
-		unmap_low_page(pte);
 
 		spin_lock(&init_mm.page_table_lock);
-		pmd_populate_kernel(&init_mm, pmd, __va(pte_phys));
+		pmd_populate_kernel(&init_mm, pmd, pte);
 		spin_unlock(&init_mm.page_table_lock);
 	}
 	update_page_count(PG_LEVEL_2M, pages);
@@ -492,27 +527,24 @@ phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end,
 	int i = pud_index(addr);
 
 	for (; i < PTRS_PER_PUD; i++, addr = next) {
-		unsigned long pmd_phys;
 		pud_t *pud = pud_page + pud_index(addr);
 		pmd_t *pmd;
 		pgprot_t prot = PAGE_KERNEL;
 
-		if (addr >= end)
-			break;
-
 		next = (addr & PUD_MASK) + PUD_SIZE;
-
-		if (!after_bootmem && !e820_any_mapped(addr, next, 0)) {
-			set_pud(pud, __pud(0));
+		if (addr >= end) {
+			if (!after_bootmem &&
+			    !e820_any_mapped(addr & PUD_MASK, next, E820_RAM) &&
+			    !e820_any_mapped(addr & PUD_MASK, next, E820_RESERVED_KERN))
+				set_pud(pud, __pud(0));
 			continue;
 		}
 
 		if (pud_val(*pud)) {
 			if (!pud_large(*pud)) {
-				pmd = map_low_page(pmd_offset(pud, 0));
+				pmd = pmd_offset(pud, 0);
 				last_map_addr = phys_pmd_init(pmd, addr, end,
 							 page_size_mask, prot);
-				unmap_low_page(pmd);
 				__flush_tlb_all();
 				continue;
 			}
@@ -541,19 +573,19 @@ phys_pud_init(pud_t *pud_page, unsigned long addr, unsigned long end,
 			pages++;
 			spin_lock(&init_mm.page_table_lock);
 			set_pte((pte_t *)pud,
-				pfn_pte(addr >> PAGE_SHIFT, PAGE_KERNEL_LARGE));
+				pfn_pte((addr & PUD_MASK) >> PAGE_SHIFT,
+					PAGE_KERNEL_LARGE));
 			spin_unlock(&init_mm.page_table_lock);
 			last_map_addr = next;
 			continue;
 		}
 
-		pmd = alloc_low_page(&pmd_phys);
+		pmd = alloc_low_page();
 		last_map_addr = phys_pmd_init(pmd, addr, end, page_size_mask,
 					      prot);
-		unmap_low_page(pmd);
 
 		spin_lock(&init_mm.page_table_lock);
-		pud_populate(&init_mm, pud, __va(pmd_phys));
+		pud_populate(&init_mm, pud, pmd);
 		spin_unlock(&init_mm.page_table_lock);
 	}
 	__flush_tlb_all();
@@ -578,28 +610,23 @@ kernel_physical_mapping_init(unsigned long start,
 
 	for (; start < end; start = next) {
 		pgd_t *pgd = pgd_offset_k(start);
-		unsigned long pud_phys;
 		pud_t *pud;
 
-		next = (start + PGDIR_SIZE) & PGDIR_MASK;
-		if (next > end)
-			next = end;
+		next = (start & PGDIR_MASK) + PGDIR_SIZE;
 
 		if (pgd_val(*pgd)) {
-			pud = map_low_page((pud_t *)pgd_page_vaddr(*pgd));
+			pud = (pud_t *)pgd_page_vaddr(*pgd);
 			last_map_addr = phys_pud_init(pud, __pa(start),
 						 __pa(end), page_size_mask);
-			unmap_low_page(pud);
 			continue;
 		}
 
-		pud = alloc_low_page(&pud_phys);
-		last_map_addr = phys_pud_init(pud, __pa(start), __pa(next),
+		pud = alloc_low_page();
+		last_map_addr = phys_pud_init(pud, __pa(start), __pa(end),
 						 page_size_mask);
-		unmap_low_page(pud);
 
 		spin_lock(&init_mm.page_table_lock);
-		pgd_populate(&init_mm, pgd, __va(pud_phys));
+		pgd_populate(&init_mm, pgd, pud);
 		spin_unlock(&init_mm.page_table_lock);
 		pgd_changed = true;
 	}
@@ -664,13 +691,11 @@ int arch_add_memory(int nid, u64 start, u64 size)
 {
 	struct pglist_data *pgdat = NODE_DATA(nid);
 	struct zone *zone = pgdat->node_zones + ZONE_NORMAL;
-	unsigned long last_mapped_pfn, start_pfn = start >> PAGE_SHIFT;
+	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
 	int ret;
 
-	last_mapped_pfn = init_memory_mapping(start, start + size);
-	if (last_mapped_pfn > max_pfn_mapped)
-		max_pfn_mapped = last_mapped_pfn;
+	init_memory_mapping(start, start + size);
 
 	ret = __add_pages(nid, zone, start_pfn, nr_pages);
 	WARN_ON_ONCE(ret);
@@ -686,6 +711,16 @@ EXPORT_SYMBOL_GPL(arch_add_memory);
 
 static struct kcore_list kcore_vsyscall;
 
+static void __init register_page_bootmem_info(void)
+{
+#ifdef CONFIG_NUMA
+	int i;
+
+	for_each_online_node(i)
+		register_page_bootmem_info_node(NODE_DATA(i));
+#endif
+}
+
 void __init mem_init(void)
 {
 	long codesize, reservedpages, datasize, initsize;
@@ -698,11 +733,8 @@ void __init mem_init(void)
 	reservedpages = 0;
 
 	/* this will put all low memory onto the freelists */
-#ifdef CONFIG_NUMA
-	totalram_pages = numa_free_all_bootmem();
-#else
+	register_page_bootmem_info();
 	totalram_pages = free_all_bootmem();
-#endif
 
 	absent_pages = absent_pages_in_range(0, max_pfn);
 	reservedpages = max_pfn - totalram_pages - absent_pages;
@@ -776,6 +808,7 @@ void mark_rodata_ro(void)
 	unsigned long end = (unsigned long) &__end_rodata_hpage_align;
 	unsigned long text_end = PFN_ALIGN(&__stop___ex_table);
 	unsigned long rodata_end = PFN_ALIGN(&__end_rodata);
+	unsigned long all_end = PFN_ALIGN(&_end);
 
 	printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
 	       (end - start) >> 10);
@@ -784,10 +817,10 @@ void mark_rodata_ro(void)
 	kernel_set_to_readonly = 1;
 
 	/*
-	 * The rodata section (but not the kernel text!) should also be
-	 * not-executable.
+	 * The rodata/data/bss/brk section (but not the kernel text!)
+	 * should also be not-executable.
 	 */
-	set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT);
+	set_memory_nx(rodata_start, (all_end - rodata_start) >> PAGE_SHIFT);
 
 	rodata_test();
 

arch/x86/mm/mm_internal.h

@@ -0,0 +1,19 @@
+#ifndef __X86_MM_INTERNAL_H
+#define __X86_MM_INTERNAL_H
+
+void *alloc_low_pages(unsigned int num);
+static inline void *alloc_low_page(void)
+{
+	return alloc_low_pages(1);
+}
+
+void early_ioremap_page_table_range_init(void);
+
+unsigned long kernel_physical_mapping_init(unsigned long start,
+					     unsigned long end,
+					     unsigned long page_size_mask);
+void zone_sizes_init(void);
+
+extern int after_bootmem;
+
+#endif	/* __X86_MM_INTERNAL_H */

arch/x86/mm/numa_64.c

@@ -10,16 +10,3 @@ void __init initmem_init(void)
 {
 	x86_numa_init();
 }
-
-unsigned long __init numa_free_all_bootmem(void)
-{
-	unsigned long pages = 0;
-	int i;
-
-	for_each_online_node(i)
-		pages += free_all_bootmem_node(NODE_DATA(i));
-
-	pages += free_low_memory_core_early(MAX_NUMNODES);
-
-	return pages;
-}

arch/x86/mm/pageattr.c

@@ -579,16 +579,10 @@ static int split_large_page(pte_t *kpte, unsigned long address)
 	for (i = 0; i < PTRS_PER_PTE; i++, pfn += pfninc)
 		set_pte(&pbase[i], pfn_pte(pfn, ref_prot));
 
-	if (address >= (unsigned long)__va(0) &&
-		address < (unsigned long)__va(max_low_pfn_mapped << PAGE_SHIFT))
+	if (pfn_range_is_mapped(PFN_DOWN(__pa(address)),
+				PFN_DOWN(__pa(address)) + 1))
 		split_page_count(level);
 
-#ifdef CONFIG_X86_64
-	if (address >= (unsigned long)__va(1UL<<32) &&
-		address < (unsigned long)__va(max_pfn_mapped << PAGE_SHIFT))
-		split_page_count(level);
-#endif
-
 	/*
 	 * Install the new, split up pagetable.
 	 *
@@ -757,13 +751,9 @@ static int cpa_process_alias(struct cpa_data *cpa)
 	unsigned long vaddr;
 	int ret;
 
-	if (cpa->pfn >= max_pfn_mapped)
+	if (!pfn_range_is_mapped(cpa->pfn, cpa->pfn + 1))
 		return 0;
 
-#ifdef CONFIG_X86_64
-	if (cpa->pfn >= max_low_pfn_mapped && cpa->pfn < (1UL<<(32-PAGE_SHIFT)))
-		return 0;
-#endif
 	/*
 	 * No need to redo, when the primary call touched the direct
 	 * mapping already:

arch/x86/platform/efi/efi.c

@@ -835,7 +835,7 @@ void __init efi_enter_virtual_mode(void)
 	efi_memory_desc_t *md, *prev_md = NULL;
 	efi_status_t status;
 	unsigned long size;
-	u64 end, systab, end_pfn;
+	u64 end, systab, start_pfn, end_pfn;
 	void *p, *va, *new_memmap = NULL;
 	int count = 0;
 
@@ -888,10 +888,9 @@ void __init efi_enter_virtual_mode(void)
 		size = md->num_pages << EFI_PAGE_SHIFT;
 		end = md->phys_addr + size;
 
+		start_pfn = PFN_DOWN(md->phys_addr);
 		end_pfn = PFN_UP(end);
-		if (end_pfn <= max_low_pfn_mapped
-		    || (end_pfn > (1UL << (32 - PAGE_SHIFT))
-			&& end_pfn <= max_pfn_mapped)) {
+		if (pfn_range_is_mapped(start_pfn, end_pfn)) {
 			va = __va(md->phys_addr);
 
 			if (!(md->attribute & EFI_MEMORY_WB))

arch/x86/power/hibernate_64.c

@@ -11,6 +11,8 @@
 #include <linux/gfp.h>
 #include <linux/smp.h>
 #include <linux/suspend.h>
+
+#include <asm/init.h>
 #include <asm/proto.h>
 #include <asm/page.h>
 #include <asm/pgtable.h>
@@ -39,41 +41,21 @@ pgd_t *temp_level4_pgt;
 
 void *relocated_restore_code;
 
-static int res_phys_pud_init(pud_t *pud, unsigned long address, unsigned long end)
+static void *alloc_pgt_page(void *context)
 {
-	long i, j;
-
-	i = pud_index(address);
-	pud = pud + i;
-	for (; i < PTRS_PER_PUD; pud++, i++) {
-		unsigned long paddr;
-		pmd_t *pmd;
-
-		paddr = address + i*PUD_SIZE;
-		if (paddr >= end)
-			break;
-
-		pmd = (pmd_t *)get_safe_page(GFP_ATOMIC);
-		if (!pmd)
-			return -ENOMEM;
-		set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
-		for (j = 0; j < PTRS_PER_PMD; pmd++, j++, paddr += PMD_SIZE) {
-			unsigned long pe;
-
-			if (paddr >= end)
-				break;
-			pe = __PAGE_KERNEL_LARGE_EXEC | paddr;
-			pe &= __supported_pte_mask;
-			set_pmd(pmd, __pmd(pe));
-		}
-	}
-	return 0;
+	return (void *)get_safe_page(GFP_ATOMIC);
 }
 
 static int set_up_temporary_mappings(void)
 {
-	unsigned long start, end, next;
-	int error;
+	struct x86_mapping_info info = {
+		.alloc_pgt_page	= alloc_pgt_page,
+		.pmd_flag	= __PAGE_KERNEL_LARGE_EXEC,
+		.kernel_mapping = true,
+	};
+	unsigned long mstart, mend;
+	int result;
+	int i;
 
 	temp_level4_pgt = (pgd_t *)get_safe_page(GFP_ATOMIC);
 	if (!temp_level4_pgt)
@@ -84,21 +66,17 @@ static int set_up_temporary_mappings(void)
 		init_level4_pgt[pgd_index(__START_KERNEL_map)]);
 
 	/* Set up the direct mapping from scratch */
-	start = (unsigned long)pfn_to_kaddr(0);
-	end = (unsigned long)pfn_to_kaddr(max_pfn);
-
-	for (; start < end; start = next) {
-		pud_t *pud = (pud_t *)get_safe_page(GFP_ATOMIC);
-		if (!pud)
-			return -ENOMEM;
-		next = start + PGDIR_SIZE;
-		if (next > end)
-			next = end;
-		if ((error = res_phys_pud_init(pud, __pa(start), __pa(next))))
-			return error;
-		set_pgd(temp_level4_pgt + pgd_index(start),
-			mk_kernel_pgd(__pa(pud)));
+	for (i = 0; i < nr_pfn_mapped; i++) {
+		mstart = pfn_mapped[i].start << PAGE_SHIFT;
+		mend   = pfn_mapped[i].end << PAGE_SHIFT;
+
+		result = kernel_ident_mapping_init(&info, temp_level4_pgt,
+						   mstart, mend);
+
+		if (result)
+			return result;
 	}
+
 	return 0;
 }
 

arch/x86/realmode/init.c

@@ -8,9 +8,26 @@
 struct real_mode_header *real_mode_header;
 u32 *trampoline_cr4_features;
 
-void __init setup_real_mode(void)
+void __init reserve_real_mode(void)
 {
 	phys_addr_t mem;
+	unsigned char *base;
+	size_t size = PAGE_ALIGN(real_mode_blob_end - real_mode_blob);
+
+	/* Has to be under 1M so we can execute real-mode AP code. */
+	mem = memblock_find_in_range(0, 1<<20, size, PAGE_SIZE);
+	if (!mem)
+		panic("Cannot allocate trampoline\n");
+
+	base = __va(mem);
+	memblock_reserve(mem, size);
+	real_mode_header = (struct real_mode_header *) base;
+	printk(KERN_DEBUG "Base memory trampoline at [%p] %llx size %zu\n",
+	       base, (unsigned long long)mem, size);
+}
+
+void __init setup_real_mode(void)
+{
 	u16 real_mode_seg;
 	u32 *rel;
 	u32 count;
@@ -25,16 +42,7 @@ void __init setup_real_mode(void)
 	u64 efer;
 #endif
 
-	/* Has to be in very low memory so we can execute real-mode AP code. */
-	mem = memblock_find_in_range(0, 1<<20, size, PAGE_SIZE);
-	if (!mem)
-		panic("Cannot allocate trampoline\n");
-
-	base = __va(mem);
-	memblock_reserve(mem, size);
-	real_mode_header = (struct real_mode_header *) base;
-	printk(KERN_DEBUG "Base memory trampoline at [%p] %llx size %zu\n",
-	       base, (unsigned long long)mem, size);
+	base = (unsigned char *)real_mode_header;
 
 	memcpy(base, real_mode_blob, size);
 
@@ -78,16 +86,18 @@ void __init setup_real_mode(void)
 	*trampoline_cr4_features = read_cr4();
 
 	trampoline_pgd = (u64 *) __va(real_mode_header->trampoline_pgd);
-	trampoline_pgd[0] = __pa_symbol(level3_ident_pgt) + _KERNPG_TABLE;
-	trampoline_pgd[511] = __pa_symbol(level3_kernel_pgt) + _KERNPG_TABLE;
+	trampoline_pgd[0] = init_level4_pgt[pgd_index(__PAGE_OFFSET)].pgd;
+	trampoline_pgd[511] = init_level4_pgt[511].pgd;
 #endif
 }
 
 /*
- * set_real_mode_permissions() gets called very early, to guarantee the
- * availability of low memory.  This is before the proper kernel page
+ * reserve_real_mode() gets called very early, to guarantee the
+ * availability of low memory. This is before the proper kernel page
  * tables are set up, so we cannot set page permissions in that
- * function.  Thus, we use an arch_initcall instead.
+ * function. Also trampoline code will be executed by APs so we
+ * need to mark it executable at do_pre_smp_initcalls() at least,
+ * thus run it as a early_initcall().
  */
 static int __init set_real_mode_permissions(void)
 {
@@ -111,5 +121,4 @@ static int __init set_real_mode_permissions(void)
 
 	return 0;
 }
-
-arch_initcall(set_real_mode_permissions);
+early_initcall(set_real_mode_permissions);

arch/x86/tools/relocs.c

@@ -814,12 +814,14 @@ int main(int argc, char **argv)
 	read_relocs(fp);
 	if (show_absolute_syms) {
 		print_absolute_symbols();
-		return 0;
+		goto out;
 	}
 	if (show_absolute_relocs) {
 		print_absolute_relocs();
-		return 0;
+		goto out;
 	}
 	emit_relocs(as_text, use_real_mode);
+out:
+	fclose(fp);
 	return 0;
 }

arch/x86/xen/mmu.c

@@ -1178,20 +1178,6 @@ static void xen_exit_mmap(struct mm_struct *mm)
 
 static void xen_post_allocator_init(void);
 
-static __init void xen_mapping_pagetable_reserve(u64 start, u64 end)
-{
-	/* reserve the range used */
-	native_pagetable_reserve(start, end);
-
-	/* set as RW the rest */
-	printk(KERN_DEBUG "xen: setting RW the range %llx - %llx\n", end,
-			PFN_PHYS(pgt_buf_top));
-	while (end < PFN_PHYS(pgt_buf_top)) {
-		make_lowmem_page_readwrite(__va(end));
-		end += PAGE_SIZE;
-	}
-}
-
 #ifdef CONFIG_X86_64
 static void __init xen_cleanhighmap(unsigned long vaddr,
 				    unsigned long vaddr_end)
@@ -1503,19 +1489,6 @@ static pte_t __init mask_rw_pte(pte_t *ptep, pte_t pte)
 #else /* CONFIG_X86_64 */
 static pte_t __init mask_rw_pte(pte_t *ptep, pte_t pte)
 {
-	unsigned long pfn = pte_pfn(pte);
-
-	/*
-	 * If the new pfn is within the range of the newly allocated
-	 * kernel pagetable, and it isn't being mapped into an
-	 * early_ioremap fixmap slot as a freshly allocated page, make sure
-	 * it is RO.
-	 */
-	if (((!is_early_ioremap_ptep(ptep) &&
-			pfn >= pgt_buf_start && pfn < pgt_buf_top)) ||
-			(is_early_ioremap_ptep(ptep) && pfn != (pgt_buf_end - 1)))
-		pte = pte_wrprotect(pte);
-
 	return pte;
 }
 #endif /* CONFIG_X86_64 */
@@ -2197,7 +2170,6 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = {
 
 void __init xen_init_mmu_ops(void)
 {
-	x86_init.mapping.pagetable_reserve = xen_mapping_pagetable_reserve;
 	x86_init.paging.pagetable_init = xen_pagetable_init;
 	pv_mmu_ops = xen_mmu_ops;
 

drivers/xen/swiotlb-xen.c

@@ -231,7 +231,9 @@ retry:
 	}
 	start_dma_addr = xen_virt_to_bus(xen_io_tlb_start);
 	if (early) {
-		swiotlb_init_with_tbl(xen_io_tlb_start, xen_io_tlb_nslabs, verbose);
+		if (swiotlb_init_with_tbl(xen_io_tlb_start, xen_io_tlb_nslabs,
+			 verbose))
+			panic("Cannot allocate SWIOTLB buffer");
 		rc = 0;
 	} else
 		rc = swiotlb_late_init_with_tbl(xen_io_tlb_start, xen_io_tlb_nslabs);

include/linux/bootmem.h

@@ -99,6 +99,9 @@ void *___alloc_bootmem_node_nopanic(pg_data_t *pgdat,
 extern void *__alloc_bootmem_low(unsigned long size,
 				 unsigned long align,
 				 unsigned long goal);
+void *__alloc_bootmem_low_nopanic(unsigned long size,
+				 unsigned long align,
+				 unsigned long goal);
 extern void *__alloc_bootmem_low_node(pg_data_t *pgdat,
 				      unsigned long size,
 				      unsigned long align,
@@ -132,6 +135,8 @@ extern void *__alloc_bootmem_low_node(pg_data_t *pgdat,
 
 #define alloc_bootmem_low(x) \
 	__alloc_bootmem_low(x, SMP_CACHE_BYTES, 0)
+#define alloc_bootmem_low_pages_nopanic(x) \
+	__alloc_bootmem_low_nopanic(x, PAGE_SIZE, 0)
 #define alloc_bootmem_low_pages(x) \
 	__alloc_bootmem_low(x, PAGE_SIZE, 0)
 #define alloc_bootmem_low_pages_node(pgdat, x) \

include/linux/kexec.h

@@ -191,6 +191,7 @@ extern struct kimage *kexec_crash_image;
 /* Location of a reserved region to hold the crash kernel.
  */
 extern struct resource crashk_res;
+extern struct resource crashk_low_res;
 typedef u32 note_buf_t[KEXEC_NOTE_BYTES/4];
 extern note_buf_t __percpu *crash_notes;
 extern u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4];
@@ -199,6 +200,8 @@ extern size_t vmcoreinfo_max_size;
 
 int __init parse_crashkernel(char *cmdline, unsigned long long system_ram,
 		unsigned long long *crash_size, unsigned long long *crash_base);
+int parse_crashkernel_low(char *cmdline, unsigned long long system_ram,
+		unsigned long long *crash_size, unsigned long long *crash_base);
 int crash_shrink_memory(unsigned long new_size);
 size_t crash_get_memory_size(void);
 void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);

include/linux/memblock.h

@@ -155,6 +155,7 @@ phys_addr_t memblock_alloc_base(phys_addr_t size, phys_addr_t align,
 phys_addr_t __memblock_alloc_base(phys_addr_t size, phys_addr_t align,
 				  phys_addr_t max_addr);
 phys_addr_t memblock_phys_mem_size(void);
+phys_addr_t memblock_mem_size(unsigned long limit_pfn);
 phys_addr_t memblock_start_of_DRAM(void);
 phys_addr_t memblock_end_of_DRAM(void);
 void memblock_enforce_memory_limit(phys_addr_t memory_limit);

include/linux/mm.h

@@ -1386,7 +1386,6 @@ extern void __init mmap_init(void);
 extern void show_mem(unsigned int flags);
 extern void si_meminfo(struct sysinfo * val);
 extern void si_meminfo_node(struct sysinfo *val, int nid);
-extern int after_bootmem;
 
 extern __printf(3, 4)
 void warn_alloc_failed(gfp_t gfp_mask, int order, const char *fmt, ...);

include/linux/swiotlb.h

@@ -23,7 +23,7 @@ extern int swiotlb_force;
 #define IO_TLB_SHIFT 11
 
 extern void swiotlb_init(int verbose);
-extern void swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose);
+int swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose);
 extern unsigned long swiotlb_nr_tbl(void);
 extern int swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs);
 

kernel/kexec.c

@@ -54,6 +54,12 @@ struct resource crashk_res = {
 	.end   = 0,
 	.flags = IORESOURCE_BUSY | IORESOURCE_MEM
 };
+struct resource crashk_low_res = {
+	.name  = "Crash kernel low",
+	.start = 0,
+	.end   = 0,
+	.flags = IORESOURCE_BUSY | IORESOURCE_MEM
+};
 
 int kexec_should_crash(struct task_struct *p)
 {
@@ -1369,10 +1375,11 @@ static int __init parse_crashkernel_simple(char 		*cmdline,
  * That function is the entry point for command line parsing and should be
  * called from the arch-specific code.
  */
-int __init parse_crashkernel(char 		 *cmdline,
+static int __init __parse_crashkernel(char *cmdline,
 			     unsigned long long system_ram,
 			     unsigned long long *crash_size,
-			     unsigned long long *crash_base)
+			     unsigned long long *crash_base,
+				const char *name)
 {
 	char 	*p = cmdline, *ck_cmdline = NULL;
 	char	*first_colon, *first_space;
@@ -1382,16 +1389,16 @@ int __init parse_crashkernel(char 		 *cmdline,
 	*crash_base = 0;
 
 	/* find crashkernel and use the last one if there are more */
-	p = strstr(p, "crashkernel=");
+	p = strstr(p, name);
 	while (p) {
 		ck_cmdline = p;
-		p = strstr(p+1, "crashkernel=");
+		p = strstr(p+1, name);
 	}
 
 	if (!ck_cmdline)
 		return -EINVAL;
 
-	ck_cmdline += 12; /* strlen("crashkernel=") */
+	ck_cmdline += strlen(name);
 
 	/*
 	 * if the commandline contains a ':', then that's the extended
@@ -1409,6 +1416,23 @@ int __init parse_crashkernel(char 		 *cmdline,
 	return 0;
 }
 
+int __init parse_crashkernel(char *cmdline,
+			     unsigned long long system_ram,
+			     unsigned long long *crash_size,
+			     unsigned long long *crash_base)
+{
+	return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
+					"crashkernel=");
+}
+
+int __init parse_crashkernel_low(char *cmdline,
+			     unsigned long long system_ram,
+			     unsigned long long *crash_size,
+			     unsigned long long *crash_base)
+{
+	return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
+					"crashkernel_low=");
+}
 
 static void update_vmcoreinfo_note(void)
 {

lib/swiotlb.c

@@ -122,11 +122,18 @@ static dma_addr_t swiotlb_virt_to_bus(struct device *hwdev,
 	return phys_to_dma(hwdev, virt_to_phys(address));
 }
 
+static bool no_iotlb_memory;
+
 void swiotlb_print_info(void)
 {
 	unsigned long bytes = io_tlb_nslabs << IO_TLB_SHIFT;
 	unsigned char *vstart, *vend;
 
+	if (no_iotlb_memory) {
+		pr_warn("software IO TLB: No low mem\n");
+		return;
+	}
+
 	vstart = phys_to_virt(io_tlb_start);
 	vend = phys_to_virt(io_tlb_end);
 
@@ -136,7 +143,7 @@ void swiotlb_print_info(void)
 	       bytes >> 20, vstart, vend - 1);
 }
 
-void __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
+int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
 {
 	void *v_overflow_buffer;
 	unsigned long i, bytes;
@@ -150,9 +157,10 @@ void __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
 	/*
 	 * Get the overflow emergency buffer
 	 */
-	v_overflow_buffer = alloc_bootmem_low_pages(PAGE_ALIGN(io_tlb_overflow));
+	v_overflow_buffer = alloc_bootmem_low_pages_nopanic(
+						PAGE_ALIGN(io_tlb_overflow));
 	if (!v_overflow_buffer)
-		panic("Cannot allocate SWIOTLB overflow buffer!\n");
+		return -ENOMEM;
 
 	io_tlb_overflow_buffer = __pa(v_overflow_buffer);
 
@@ -169,15 +177,19 @@ void __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
 
 	if (verbose)
 		swiotlb_print_info();
+
+	return 0;
 }
 
 /*
  * Statically reserve bounce buffer space and initialize bounce buffer data
  * structures for the software IO TLB used to implement the DMA API.
  */
-static void __init
-swiotlb_init_with_default_size(size_t default_size, int verbose)
+void  __init
+swiotlb_init(int verbose)
 {
+	/* default to 64MB */
+	size_t default_size = 64UL<<20;
 	unsigned char *vstart;
 	unsigned long bytes;
 
@@ -188,20 +200,16 @@ swiotlb_init_with_default_size(size_t default_size, int verbose)
 
 	bytes = io_tlb_nslabs << IO_TLB_SHIFT;
 
-	/*
-	 * Get IO TLB memory from the low pages
-	 */
-	vstart = alloc_bootmem_low_pages(PAGE_ALIGN(bytes));
-	if (!vstart)
-		panic("Cannot allocate SWIOTLB buffer");
-
-	swiotlb_init_with_tbl(vstart, io_tlb_nslabs, verbose);
-}
+	/* Get IO TLB memory from the low pages */
+	vstart = alloc_bootmem_low_pages_nopanic(PAGE_ALIGN(bytes));
+	if (vstart && !swiotlb_init_with_tbl(vstart, io_tlb_nslabs, verbose))
+		return;
 
-void __init
-swiotlb_init(int verbose)
-{
-	swiotlb_init_with_default_size(64 * (1<<20), verbose);	/* default to 64MB */
+	if (io_tlb_start)
+		free_bootmem(io_tlb_start,
+				 PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT));
+	pr_warn("Cannot allocate SWIOTLB buffer");
+	no_iotlb_memory = true;
 }
 
 /*
@@ -405,6 +413,9 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev,
 	unsigned long offset_slots;
 	unsigned long max_slots;
 
+	if (no_iotlb_memory)
+		panic("Can not allocate SWIOTLB buffer earlier and can't now provide you with the DMA bounce buffer");
+
 	mask = dma_get_seg_boundary(hwdev);
 
 	tbl_dma_addr &= mask;

mm/bootmem.c

@@ -833,6 +833,14 @@ void * __init __alloc_bootmem_low(unsigned long size, unsigned long align,
 	return ___alloc_bootmem(size, align, goal, ARCH_LOW_ADDRESS_LIMIT);
 }
 
+void * __init __alloc_bootmem_low_nopanic(unsigned long size,
+					  unsigned long align,
+					  unsigned long goal)
+{
+	return ___alloc_bootmem_nopanic(size, align, goal,
+					ARCH_LOW_ADDRESS_LIMIT);
+}
+
 /**
  * __alloc_bootmem_low_node - allocate low boot memory from a specific node
  * @pgdat: node to allocate from

mm/memblock.c

@@ -828,6 +828,23 @@ phys_addr_t __init memblock_phys_mem_size(void)
 	return memblock.memory.total_size;
 }
 
+phys_addr_t __init memblock_mem_size(unsigned long limit_pfn)
+{
+	unsigned long pages = 0;
+	struct memblock_region *r;
+	unsigned long start_pfn, end_pfn;
+
+	for_each_memblock(memory, r) {
+		start_pfn = memblock_region_memory_base_pfn(r);
+		end_pfn = memblock_region_memory_end_pfn(r);
+		start_pfn = min_t(unsigned long, start_pfn, limit_pfn);
+		end_pfn = min_t(unsigned long, end_pfn, limit_pfn);
+		pages += end_pfn - start_pfn;
+	}
+
+	return (phys_addr_t)pages << PAGE_SHIFT;
+}
+
 /* lowest address */
 phys_addr_t __init_memblock memblock_start_of_DRAM(void)
 {

mm/nobootmem.c

@@ -153,21 +153,6 @@ static void reset_node_lowmem_managed_pages(pg_data_t *pgdat)
 			z->managed_pages = 0;
 }
 
-/**
- * free_all_bootmem_node - release a node's free pages to the buddy allocator
- * @pgdat: node to be released
- *
- * Returns the number of pages actually released.
- */
-unsigned long __init free_all_bootmem_node(pg_data_t *pgdat)
-{
-	register_page_bootmem_info_node(pgdat);
-	reset_node_lowmem_managed_pages(pgdat);
-
-	/* free_low_memory_core_early(MAX_NUMNODES) will be called later */
-	return 0;
-}
-
 /**
  * free_all_bootmem - release free pages to the buddy allocator
  *
@@ -406,6 +391,14 @@ void * __init __alloc_bootmem_low(unsigned long size, unsigned long align,
 	return ___alloc_bootmem(size, align, goal, ARCH_LOW_ADDRESS_LIMIT);
 }
 
+void * __init __alloc_bootmem_low_nopanic(unsigned long size,
+					  unsigned long align,
+					  unsigned long goal)
+{
+	return ___alloc_bootmem_nopanic(size, align, goal,
+					ARCH_LOW_ADDRESS_LIMIT);
+}
+
 /**
  * __alloc_bootmem_low_node - allocate low boot memory from a specific node
  * @pgdat: node to allocate from