arch/arm/mm/init.c - kernel/msm - Gitiles

 /*
  *  linux/arch/arm/mm/init.c
  *
  *  Copyright (C) 1995-2005 Russell King
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */
 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/swap.h>
 #include <linux/init.h>
 #include <linux/bootmem.h>
 #include <linux/mman.h>
 #include <linux/nodemask.h>
 #include <linux/initrd.h>

 #include <asm/mach-types.h>
 #include <asm/setup.h>
 #include <asm/sizes.h>
 #include <asm/tlb.h>

 #include <asm/mach/arch.h>
 #include <asm/mach/map.h>

 #include "mm.h"

 extern void _text, _etext, __data_start, _end, __init_begin, __init_end;
 extern unsigned long phys_initrd_start;
 extern unsigned long phys_initrd_size;

 /*
  * This is used to pass memory configuration data from paging_init
  * to mem_init, and by show_mem() to skip holes in the memory map.
  */
 static struct meminfo meminfo = { 0, };

 #define for_each_nodebank(iter,mi,no)			\
 	for (iter = 0; iter < mi->nr_banks; iter++)	\
 		if (mi->bank[iter].node == no)

 void show_mem(void)
 {
 	int free = 0, total = 0, reserved = 0;
 	int shared = 0, cached = 0, slab = 0, node, i;
 	struct meminfo * mi = &meminfo;

 	printk("Mem-info:\n");
 	show_free_areas();
 	for_each_online_node(node) {
 		pg_data_t *n = NODE_DATA(node);
 		struct page *map = n->node_mem_map - n->node_start_pfn;

 		for_each_nodebank (i,mi,node) {
 			unsigned int pfn1, pfn2;
 			struct page *page, *end;

 			pfn1 = __phys_to_pfn(mi->bank[i].start);
 			pfn2 = __phys_to_pfn(mi->bank[i].size + mi->bank[i].start);

 			page = map + pfn1;
 			end  = map + pfn2;

 			do {
 				total++;
 				if (PageReserved(page))
 					reserved++;
 				else if (PageSwapCache(page))
 					cached++;
 				else if (PageSlab(page))
 					slab++;
 				else if (!page_count(page))
 					free++;
 				else
 					shared += page_count(page) - 1;
 				page++;
 			} while (page < end);
 		}
 	}

 	printk("%d pages of RAM\n", total);
 	printk("%d free pages\n", free);
 	printk("%d reserved pages\n", reserved);
 	printk("%d slab pages\n", slab);
 	printk("%d pages shared\n", shared);
 	printk("%d pages swap cached\n", cached);
 }

 /*
  * FIXME: We really want to avoid allocating the bootmap bitmap
  * over the top of the initrd.  Hopefully, this is located towards
  * the start of a bank, so if we allocate the bootmap bitmap at
  * the end, we won't clash.
  */
 static unsigned int __init
 find_bootmap_pfn(int node, struct meminfo *mi, unsigned int bootmap_pages)
 {
 	unsigned int start_pfn, bank, bootmap_pfn;

 	start_pfn   = PAGE_ALIGN(__pa(&_end)) >> PAGE_SHIFT;
 	bootmap_pfn = 0;

 	for_each_nodebank(bank, mi, node) {
 		unsigned int start, end;

 		start = mi->bank[bank].start >> PAGE_SHIFT;
 		end   = (mi->bank[bank].size +
 			 mi->bank[bank].start) >> PAGE_SHIFT;

 		if (end < start_pfn)
 			continue;

 		if (start < start_pfn)
 			start = start_pfn;

 		if (end <= start)
 			continue;

 		if (end - start >= bootmap_pages) {
 			bootmap_pfn = start;
 			break;
 		}
 	}

 	if (bootmap_pfn == 0)
 		BUG();

 	return bootmap_pfn;
 }

 static int __init check_initrd(struct meminfo *mi)
 {
 	int initrd_node = -2;
 #ifdef CONFIG_BLK_DEV_INITRD
 	unsigned long end = phys_initrd_start + phys_initrd_size;

 	/*
 	 * Make sure that the initrd is within a valid area of
 	 * memory.
 	 */
 	if (phys_initrd_size) {
 		unsigned int i;

 		initrd_node = -1;

 		for (i = 0; i < mi->nr_banks; i++) {
 			unsigned long bank_end;

 			bank_end = mi->bank[i].start + mi->bank[i].size;

 			if (mi->bank[i].start <= phys_initrd_start &&
 			    end <= bank_end)
 				initrd_node = mi->bank[i].node;
 		}
 	}

 	if (initrd_node == -1) {
 		printk(KERN_ERR "initrd (0x%08lx - 0x%08lx) extends beyond "
 		       "physical memory - disabling initrd\n",
 		       phys_initrd_start, end);
 		phys_initrd_start = phys_initrd_size = 0;
 	}
 #endif

 	return initrd_node;
 }

 static inline void map_memory_bank(struct membank *bank)
 {
 #ifdef CONFIG_MMU
 	struct map_desc map;

 	map.pfn = __phys_to_pfn(bank->start);
 	map.virtual = __phys_to_virt(bank->start);
 	map.length = bank->size;
 	map.type = MT_MEMORY;

 	create_mapping(&map);
 #endif
 }

 static unsigned long __init
 bootmem_init_node(int node, int initrd_node, struct meminfo *mi)
 {
 	unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
 	unsigned long start_pfn, end_pfn, boot_pfn;
 	unsigned int boot_pages;
 	pg_data_t *pgdat;
 	int i;

 	start_pfn = -1UL;
 	end_pfn = 0;

 	/*
 	 * Calculate the pfn range, and map the memory banks for this node.
 	 */
 	for_each_nodebank(i, mi, node) {
 		struct membank *bank = &mi->bank[i];
 		unsigned long start, end;

 		start = bank->start >> PAGE_SHIFT;
 		end = (bank->start + bank->size) >> PAGE_SHIFT;

 		if (start_pfn > start)
 			start_pfn = start;
 		if (end_pfn < end)
 			end_pfn = end;

 		map_memory_bank(bank);
 	}

 	/*
 	 * If there is no memory in this node, ignore it.
 	 */
 	if (end_pfn == 0)
 		return end_pfn;

 	/*
 	 * Allocate the bootmem bitmap page.
 	 */
 	boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
 	boot_pfn = find_bootmap_pfn(node, mi, boot_pages);

 	/*
 	 * Initialise the bootmem allocator for this node, handing the
 	 * memory banks over to bootmem.
 	 */
 	node_set_online(node);
 	pgdat = NODE_DATA(node);
 	init_bootmem_node(pgdat, boot_pfn, start_pfn, end_pfn);

 	for_each_nodebank(i, mi, node)
 		free_bootmem_node(pgdat, mi->bank[i].start, mi->bank[i].size);

 	/*
 	 * Reserve the bootmem bitmap for this node.
 	 */
 	reserve_bootmem_node(pgdat, boot_pfn << PAGE_SHIFT,
 			     boot_pages << PAGE_SHIFT, BOOTMEM_DEFAULT);

 #ifdef CONFIG_BLK_DEV_INITRD
 	/*
 	 * If the initrd is in this node, reserve its memory.
 	 */
 	if (node == initrd_node) {
 		reserve_bootmem_node(pgdat, phys_initrd_start,
 				     phys_initrd_size, BOOTMEM_DEFAULT);
 		initrd_start = __phys_to_virt(phys_initrd_start);
 		initrd_end = initrd_start + phys_initrd_size;
 	}
 #endif

 	/*
 	 * Finally, reserve any node zero regions.
 	 */
 	if (node == 0)
 		reserve_node_zero(pgdat);

 	/*
 	 * initialise the zones within this node.
 	 */
 	memset(zone_size, 0, sizeof(zone_size));
 	memset(zhole_size, 0, sizeof(zhole_size));

 	/*
 	 * The size of this node has already been determined.  If we need
 	 * to do anything fancy with the allocation of this memory to the
 	 * zones, now is the time to do it.
 	 */
 	zone_size[0] = end_pfn - start_pfn;

 	/*
 	 * For each bank in this node, calculate the size of the holes.
 	 *  holes = node_size - sum(bank_sizes_in_node)
 	 */
 	zhole_size[0] = zone_size[0];
 	for_each_nodebank(i, mi, node)
 		zhole_size[0] -= mi->bank[i].size >> PAGE_SHIFT;

 	/*
 	 * Adjust the sizes according to any special requirements for
 	 * this machine type.
 	 */
 	arch_adjust_zones(node, zone_size, zhole_size);

 	free_area_init_node(node, zone_size, start_pfn, zhole_size);

 	return end_pfn;
 }

 void __init bootmem_init(struct meminfo *mi)
 {
 	unsigned long memend_pfn = 0;
 	int node, initrd_node, i;

 	/*
 	 * Invalidate the node number for empty or invalid memory banks
 	 */
 	for (i = 0; i < mi->nr_banks; i++)
 		if (mi->bank[i].size == 0 || mi->bank[i].node >= MAX_NUMNODES)
 			mi->bank[i].node = -1;

 	memcpy(&meminfo, mi, sizeof(meminfo));

 	/*
 	 * Locate which node contains the ramdisk image, if any.
 	 */
 	initrd_node = check_initrd(mi);

 	/*
 	 * Run through each node initialising the bootmem allocator.
 	 */
 	for_each_node(node) {
 		unsigned long end_pfn;

 		end_pfn = bootmem_init_node(node, initrd_node, mi);

 		/*
 		 * Remember the highest memory PFN.
 		 */
 		if (end_pfn > memend_pfn)
 			memend_pfn = end_pfn;
 	}

 	high_memory = __va(memend_pfn << PAGE_SHIFT);

 	/*
 	 * This doesn't seem to be used by the Linux memory manager any
 	 * more, but is used by ll_rw_block.  If we can get rid of it, we
 	 * also get rid of some of the stuff above as well.
 	 *
 	 * Note: max_low_pfn and max_pfn reflect the number of _pages_ in
 	 * the system, not the maximum PFN.
 	 */
 	max_pfn = max_low_pfn = memend_pfn - PHYS_PFN_OFFSET;
 }

 static inline void free_area(unsigned long addr, unsigned long end, char *s)
 {
 	unsigned int size = (end - addr) >> 10;

 	for (; addr < end; addr += PAGE_SIZE) {
 		struct page *page = virt_to_page(addr);
 		ClearPageReserved(page);
 		init_page_count(page);
 		free_page(addr);
 		totalram_pages++;
 	}

 	if (size && s)
 		printk(KERN_INFO "Freeing %s memory: %dK\n", s, size);
 }

 static inline void
 free_memmap(int node, unsigned long start_pfn, unsigned long end_pfn)
 {
 	struct page *start_pg, *end_pg;
 	unsigned long pg, pgend;

 	/*
 	 * Convert start_pfn/end_pfn to a struct page pointer.
 	 */
 	start_pg = pfn_to_page(start_pfn);
 	end_pg = pfn_to_page(end_pfn);

 	/*
 	 * Convert to physical addresses, and
 	 * round start upwards and end downwards.
 	 */
 	pg = PAGE_ALIGN(__pa(start_pg));
 	pgend = __pa(end_pg) & PAGE_MASK;

 	/*
 	 * If there are free pages between these,
 	 * free the section of the memmap array.
 	 */
 	if (pg < pgend)
 		free_bootmem_node(NODE_DATA(node), pg, pgend - pg);
 }

 /*
  * The mem_map array can get very big.  Free the unused area of the memory map.
  */
 static void __init free_unused_memmap_node(int node, struct meminfo *mi)
 {
 	unsigned long bank_start, prev_bank_end = 0;
 	unsigned int i;

 	/*
 	 * [FIXME] This relies on each bank being in address order.  This
 	 * may not be the case, especially if the user has provided the
 	 * information on the command line.
 	 */
 	for_each_nodebank(i, mi, node) {
 		bank_start = mi->bank[i].start >> PAGE_SHIFT;
 		if (bank_start < prev_bank_end) {
 			printk(KERN_ERR "MEM: unordered memory banks.  "
 				"Not freeing memmap.\n");
 			break;
 		}

 		/*
 		 * If we had a previous bank, and there is a space
 		 * between the current bank and the previous, free it.
 		 */
 		if (prev_bank_end && prev_bank_end != bank_start)
 			free_memmap(node, prev_bank_end, bank_start);

 		prev_bank_end = (mi->bank[i].start +
 				 mi->bank[i].size) >> PAGE_SHIFT;
 	}
 }

 /*
  * mem_init() marks the free areas in the mem_map and tells us how much
  * memory is free.  This is done after various parts of the system have
  * claimed their memory after the kernel image.
  */
 void __init mem_init(void)
 {
 	unsigned int codepages, datapages, initpages;
 	int i, node;

 	codepages = &_etext - &_text;
 	datapages = &_end - &__data_start;
 	initpages = &__init_end - &__init_begin;

 #ifndef CONFIG_DISCONTIGMEM
 	max_mapnr   = virt_to_page(high_memory) - mem_map;
 #endif

 	/* this will put all unused low memory onto the freelists */
 	for_each_online_node(node) {
 		pg_data_t *pgdat = NODE_DATA(node);

 		free_unused_memmap_node(node, &meminfo);

 		if (pgdat->node_spanned_pages != 0)
 			totalram_pages += free_all_bootmem_node(pgdat);
 	}

 #ifdef CONFIG_SA1111
 	/* now that our DMA memory is actually so designated, we can free it */
 	free_area(PAGE_OFFSET, (unsigned long)swapper_pg_dir, NULL);
 #endif

 	/*
 	 * Since our memory may not be contiguous, calculate the
 	 * real number of pages we have in this system
 	 */
 	printk(KERN_INFO "Memory:");

 	num_physpages = 0;
 	for (i = 0; i < meminfo.nr_banks; i++) {
 		num_physpages += meminfo.bank[i].size >> PAGE_SHIFT;
 		printk(" %ldMB", meminfo.bank[i].size >> 20);
 	}

 	printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
 	printk(KERN_NOTICE "Memory: %luKB available (%dK code, "
 		"%dK data, %dK init)\n",
 		(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 		codepages >> 10, datapages >> 10, initpages >> 10);

 	if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
 		extern int sysctl_overcommit_memory;
 		/*
 		 * On a machine this small we won't get
 		 * anywhere without overcommit, so turn
 		 * it on by default.
 		 */
 		sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
 	}
 }

 void free_initmem(void)
 {
 	if (!machine_is_integrator() && !machine_is_cintegrator()) {
 		free_area((unsigned long)(&__init_begin),
 			  (unsigned long)(&__init_end),
 			  "init");
 	}
 }

 #ifdef CONFIG_BLK_DEV_INITRD

 static int keep_initrd;

 void free_initrd_mem(unsigned long start, unsigned long end)
 {
 	if (!keep_initrd)
 		free_area(start, end, "initrd");
 }

 static int __init keepinitrd_setup(char *__unused)
 {
 	keep_initrd = 1;
 	return 1;
 }

 __setup("keepinitrd", keepinitrd_setup);
 #endif
	/*
	* linux/arch/arm/mm/init.c
	*
	* Copyright (C) 1995-2005 Russell King
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*/
	#include <linux/kernel.h>
	#include <linux/errno.h>
	#include <linux/swap.h>
	#include <linux/init.h>
	#include <linux/bootmem.h>
	#include <linux/mman.h>
	#include <linux/nodemask.h>
	#include <linux/initrd.h>

	#include <asm/mach-types.h>
	#include <asm/setup.h>
	#include <asm/sizes.h>
	#include <asm/tlb.h>

	#include <asm/mach/arch.h>
	#include <asm/mach/map.h>

	#include "mm.h"

	extern void _text, _etext, __data_start, _end, __init_begin, __init_end;
	extern unsigned long phys_initrd_start;
	extern unsigned long phys_initrd_size;

	/*
	* This is used to pass memory configuration data from paging_init
	* to mem_init, and by show_mem() to skip holes in the memory map.
	*/
	static struct meminfo meminfo = { 0, };

	#define for_each_nodebank(iter,mi,no) \
	for (iter = 0; iter < mi->nr_banks; iter++) \
	if (mi->bank[iter].node == no)

	void show_mem(void)
	{
	int free = 0, total = 0, reserved = 0;
	int shared = 0, cached = 0, slab = 0, node, i;
	struct meminfo * mi = &meminfo;

	printk("Mem-info:\n");
	show_free_areas();
	for_each_online_node(node) {
	pg_data_t *n = NODE_DATA(node);
	struct page *map = n->node_mem_map - n->node_start_pfn;

	for_each_nodebank (i,mi,node) {
	unsigned int pfn1, pfn2;
	struct page page, end;

	pfn1 = __phys_to_pfn(mi->bank[i].start);
	pfn2 = __phys_to_pfn(mi->bank[i].size + mi->bank[i].start);

	page = map + pfn1;
	end = map + pfn2;

	do {
	total++;
	if (PageReserved(page))
	reserved++;
	else if (PageSwapCache(page))
	cached++;
	else if (PageSlab(page))
	slab++;
	else if (!page_count(page))
	free++;
	else
	shared += page_count(page) - 1;
	page++;
	} while (page < end);
	}
	}

	printk("%d pages of RAM\n", total);
	printk("%d free pages\n", free);
	printk("%d reserved pages\n", reserved);
	printk("%d slab pages\n", slab);
	printk("%d pages shared\n", shared);
	printk("%d pages swap cached\n", cached);
	}

	/*
	* FIXME: We really want to avoid allocating the bootmap bitmap
	* over the top of the initrd. Hopefully, this is located towards
	* the start of a bank, so if we allocate the bootmap bitmap at
	* the end, we won't clash.
	*/
	static unsigned int __init
	find_bootmap_pfn(int node, struct meminfo *mi, unsigned int bootmap_pages)
	{
	unsigned int start_pfn, bank, bootmap_pfn;

	start_pfn = PAGE_ALIGN(__pa(&_end)) >> PAGE_SHIFT;
	bootmap_pfn = 0;

	for_each_nodebank(bank, mi, node) {
	unsigned int start, end;

	start = mi->bank[bank].start >> PAGE_SHIFT;
	end = (mi->bank[bank].size +
	mi->bank[bank].start) >> PAGE_SHIFT;

	if (end < start_pfn)
	continue;

	if (start < start_pfn)
	start = start_pfn;

	if (end <= start)
	continue;

	if (end - start >= bootmap_pages) {
	bootmap_pfn = start;
	break;
	}
	}

	if (bootmap_pfn == 0)
	BUG();

	return bootmap_pfn;
	}

	static int __init check_initrd(struct meminfo *mi)
	{
	int initrd_node = -2;
	#ifdef CONFIG_BLK_DEV_INITRD
	unsigned long end = phys_initrd_start + phys_initrd_size;

	/*
	* Make sure that the initrd is within a valid area of
	* memory.
	*/
	if (phys_initrd_size) {
	unsigned int i;

	initrd_node = -1;

	for (i = 0; i < mi->nr_banks; i++) {
	unsigned long bank_end;

	bank_end = mi->bank[i].start + mi->bank[i].size;

	if (mi->bank[i].start <= phys_initrd_start &&
	end <= bank_end)
	initrd_node = mi->bank[i].node;
	}
	}

	if (initrd_node == -1) {
	printk(KERN_ERR "initrd (0x%08lx - 0x%08lx) extends beyond "
	"physical memory - disabling initrd\n",
	phys_initrd_start, end);
	phys_initrd_start = phys_initrd_size = 0;
	}
	#endif

	return initrd_node;
	}

	static inline void map_memory_bank(struct membank *bank)
	{
	#ifdef CONFIG_MMU
	struct map_desc map;

	map.pfn = __phys_to_pfn(bank->start);
	map.virtual = __phys_to_virt(bank->start);
	map.length = bank->size;
	map.type = MT_MEMORY;

	create_mapping(&map);
	#endif
	}

	static unsigned long __init
	bootmem_init_node(int node, int initrd_node, struct meminfo *mi)
	{
	unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
	unsigned long start_pfn, end_pfn, boot_pfn;
	unsigned int boot_pages;
	pg_data_t *pgdat;
	int i;

	start_pfn = -1UL;
	end_pfn = 0;

	/*
	* Calculate the pfn range, and map the memory banks for this node.
	*/
	for_each_nodebank(i, mi, node) {
	struct membank *bank = &mi->bank[i];
	unsigned long start, end;

	start = bank->start >> PAGE_SHIFT;
	end = (bank->start + bank->size) >> PAGE_SHIFT;

	if (start_pfn > start)
	start_pfn = start;
	if (end_pfn < end)
	end_pfn = end;

	map_memory_bank(bank);
	}

	/*
	* If there is no memory in this node, ignore it.
	*/
	if (end_pfn == 0)
	return end_pfn;

	/*
	* Allocate the bootmem bitmap page.
	*/
	boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
	boot_pfn = find_bootmap_pfn(node, mi, boot_pages);

	/*
	* Initialise the bootmem allocator for this node, handing the
	* memory banks over to bootmem.
	*/
	node_set_online(node);
	pgdat = NODE_DATA(node);
	init_bootmem_node(pgdat, boot_pfn, start_pfn, end_pfn);

	for_each_nodebank(i, mi, node)
	free_bootmem_node(pgdat, mi->bank[i].start, mi->bank[i].size);

	/*
	* Reserve the bootmem bitmap for this node.
	*/
	reserve_bootmem_node(pgdat, boot_pfn << PAGE_SHIFT,
	boot_pages << PAGE_SHIFT, BOOTMEM_DEFAULT);

	#ifdef CONFIG_BLK_DEV_INITRD
	/*
	* If the initrd is in this node, reserve its memory.
	*/
	if (node == initrd_node) {
	reserve_bootmem_node(pgdat, phys_initrd_start,
	phys_initrd_size, BOOTMEM_DEFAULT);
	initrd_start = __phys_to_virt(phys_initrd_start);
	initrd_end = initrd_start + phys_initrd_size;
	}
	#endif

	/*
	* Finally, reserve any node zero regions.
	*/
	if (node == 0)
	reserve_node_zero(pgdat);

	/*
	* initialise the zones within this node.
	*/
	memset(zone_size, 0, sizeof(zone_size));
	memset(zhole_size, 0, sizeof(zhole_size));

	/*
	* The size of this node has already been determined. If we need
	* to do anything fancy with the allocation of this memory to the
	* zones, now is the time to do it.
	*/
	zone_size[0] = end_pfn - start_pfn;

	/*
	* For each bank in this node, calculate the size of the holes.
	* holes = node_size - sum(bank_sizes_in_node)
	*/
	zhole_size[0] = zone_size[0];
	for_each_nodebank(i, mi, node)
	zhole_size[0] -= mi->bank[i].size >> PAGE_SHIFT;

	/*
	* Adjust the sizes according to any special requirements for
	* this machine type.
	*/
	arch_adjust_zones(node, zone_size, zhole_size);

	free_area_init_node(node, zone_size, start_pfn, zhole_size);

	return end_pfn;
	}

	void __init bootmem_init(struct meminfo *mi)
	{
	unsigned long memend_pfn = 0;
	int node, initrd_node, i;

	/*
	* Invalidate the node number for empty or invalid memory banks
	*/
	for (i = 0; i < mi->nr_banks; i++)
	if (mi->bank[i].size == 0 \|\| mi->bank[i].node >= MAX_NUMNODES)
	mi->bank[i].node = -1;

	memcpy(&meminfo, mi, sizeof(meminfo));

	/*
	* Locate which node contains the ramdisk image, if any.
	*/
	initrd_node = check_initrd(mi);

	/*
	* Run through each node initialising the bootmem allocator.
	*/
	for_each_node(node) {
	unsigned long end_pfn;

	end_pfn = bootmem_init_node(node, initrd_node, mi);

	/*
	* Remember the highest memory PFN.
	*/
	if (end_pfn > memend_pfn)
	memend_pfn = end_pfn;
	}

	high_memory = __va(memend_pfn << PAGE_SHIFT);

	/*
	* This doesn't seem to be used by the Linux memory manager any
	* more, but is used by ll_rw_block. If we can get rid of it, we
	* also get rid of some of the stuff above as well.
	*
	* Note: max_low_pfn and max_pfn reflect the number of _pages_ in
	* the system, not the maximum PFN.
	*/
	max_pfn = max_low_pfn = memend_pfn - PHYS_PFN_OFFSET;
	}

	static inline void free_area(unsigned long addr, unsigned long end, char *s)
	{
	unsigned int size = (end - addr) >> 10;

	for (; addr < end; addr += PAGE_SIZE) {
	struct page *page = virt_to_page(addr);
	ClearPageReserved(page);
	init_page_count(page);
	free_page(addr);
	totalram_pages++;
	}

	if (size && s)
	printk(KERN_INFO "Freeing %s memory: %dK\n", s, size);
	}

	static inline void
	free_memmap(int node, unsigned long start_pfn, unsigned long end_pfn)
	{
	struct page start_pg, end_pg;
	unsigned long pg, pgend;

	/*
	* Convert start_pfn/end_pfn to a struct page pointer.
	*/
	start_pg = pfn_to_page(start_pfn);
	end_pg = pfn_to_page(end_pfn);

	/*
	* Convert to physical addresses, and
	* round start upwards and end downwards.
	*/
	pg = PAGE_ALIGN(__pa(start_pg));
	pgend = __pa(end_pg) & PAGE_MASK;

	/*
	* If there are free pages between these,
	* free the section of the memmap array.
	*/
	if (pg < pgend)
	free_bootmem_node(NODE_DATA(node), pg, pgend - pg);
	}

	/*
	* The mem_map array can get very big. Free the unused area of the memory map.
	*/
	static void __init free_unused_memmap_node(int node, struct meminfo *mi)
	{
	unsigned long bank_start, prev_bank_end = 0;
	unsigned int i;

	/*
	* [FIXME] This relies on each bank being in address order. This
	* may not be the case, especially if the user has provided the
	* information on the command line.
	*/
	for_each_nodebank(i, mi, node) {
	bank_start = mi->bank[i].start >> PAGE_SHIFT;
	if (bank_start < prev_bank_end) {
	printk(KERN_ERR "MEM: unordered memory banks. "
	"Not freeing memmap.\n");
	break;
	}

	/*
	* If we had a previous bank, and there is a space
	* between the current bank and the previous, free it.
	*/
	if (prev_bank_end && prev_bank_end != bank_start)
	free_memmap(node, prev_bank_end, bank_start);

	prev_bank_end = (mi->bank[i].start +
	mi->bank[i].size) >> PAGE_SHIFT;
	}
	}

	/*
	* mem_init() marks the free areas in the mem_map and tells us how much
	* memory is free. This is done after various parts of the system have
	* claimed their memory after the kernel image.
	*/
	void __init mem_init(void)
	{
	unsigned int codepages, datapages, initpages;
	int i, node;

	codepages = &_etext - &_text;
	datapages = &_end - &__data_start;
	initpages = &__init_end - &__init_begin;

	#ifndef CONFIG_DISCONTIGMEM
	max_mapnr = virt_to_page(high_memory) - mem_map;
	#endif

	/* this will put all unused low memory onto the freelists */
	for_each_online_node(node) {
	pg_data_t *pgdat = NODE_DATA(node);

	free_unused_memmap_node(node, &meminfo);

	if (pgdat->node_spanned_pages != 0)
	totalram_pages += free_all_bootmem_node(pgdat);
	}

	#ifdef CONFIG_SA1111
	/* now that our DMA memory is actually so designated, we can free it */
	free_area(PAGE_OFFSET, (unsigned long)swapper_pg_dir, NULL);
	#endif

	/*
	* Since our memory may not be contiguous, calculate the
	* real number of pages we have in this system
	*/
	printk(KERN_INFO "Memory:");

	num_physpages = 0;
	for (i = 0; i < meminfo.nr_banks; i++) {
	num_physpages += meminfo.bank[i].size >> PAGE_SHIFT;
	printk(" %ldMB", meminfo.bank[i].size >> 20);
	}

	printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
	printk(KERN_NOTICE "Memory: %luKB available (%dK code, "
	"%dK data, %dK init)\n",
	(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
	codepages >> 10, datapages >> 10, initpages >> 10);

	if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
	extern int sysctl_overcommit_memory;
	/*
	* On a machine this small we won't get
	* anywhere without overcommit, so turn
	* it on by default.
	*/
	sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
	}
	}

	void free_initmem(void)
	{
	if (!machine_is_integrator() && !machine_is_cintegrator()) {
	free_area((unsigned long)(&__init_begin),
	(unsigned long)(&__init_end),
	"init");
	}
	}

	#ifdef CONFIG_BLK_DEV_INITRD

	static int keep_initrd;

	void free_initrd_mem(unsigned long start, unsigned long end)
	{
	if (!keep_initrd)
	free_area(start, end, "initrd");
	}

	static int __init keepinitrd_setup(char *__unused)
	{
	keep_initrd = 1;
	return 1;
	}

	__setup("keepinitrd", keepinitrd_setup);
	#endif