arch/x86/mm/discontig_32.c - kernel/msm-4.9 - Gitiles

 /*
  * Written by: Patricia Gaughen <gone@us.ibm.com>, IBM Corporation
  * August 2002: added remote node KVA remap - Martin J. Bligh
  *
  * Copyright (C) 2002, IBM Corp.
  *
  * All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  * NON INFRINGEMENT.  See the GNU General Public License for more
  * details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */

 #include <linux/mm.h>
 #include <linux/bootmem.h>
 #include <linux/mmzone.h>
 #include <linux/highmem.h>
 #include <linux/initrd.h>
 #include <linux/nodemask.h>
 #include <linux/module.h>
 #include <linux/kexec.h>
 #include <linux/pfn.h>
 #include <linux/swap.h>
 #include <linux/acpi.h>

 #include <asm/e820.h>
 #include <asm/setup.h>
 #include <asm/mmzone.h>
 #include <asm/bios_ebda.h>

 struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
 EXPORT_SYMBOL(node_data);
 static bootmem_data_t node0_bdata;

 /*
  * numa interface - we expect the numa architecture specific code to have
  *                  populated the following initialisation.
  *
  * 1) node_online_map  - the map of all nodes configured (online) in the system
  * 2) node_start_pfn   - the starting page frame number for a node
  * 3) node_end_pfn     - the ending page fram number for a node
  */
 unsigned long node_start_pfn[MAX_NUMNODES] __read_mostly;
 unsigned long node_end_pfn[MAX_NUMNODES] __read_mostly;


 #ifdef CONFIG_DISCONTIGMEM
 /*
  * 4) physnode_map     - the mapping between a pfn and owning node
  * physnode_map keeps track of the physical memory layout of a generic
  * numa node on a 256Mb break (each element of the array will
  * represent 256Mb of memory and will be marked by the node id.  so,
  * if the first gig is on node 0, and the second gig is on node 1
  * physnode_map will contain:
  *
  *     physnode_map[0-3] = 0;
  *     physnode_map[4-7] = 1;
  *     physnode_map[8- ] = -1;
  */
 s8 physnode_map[MAX_ELEMENTS] __read_mostly = { [0 ... (MAX_ELEMENTS - 1)] = -1};
 EXPORT_SYMBOL(physnode_map);

 void memory_present(int nid, unsigned long start, unsigned long end)
 {
 	unsigned long pfn;

 	printk(KERN_INFO "Node: %d, start_pfn: %ld, end_pfn: %ld\n",
 			nid, start, end);
 	printk(KERN_DEBUG "  Setting physnode_map array to node %d for pfns:\n", nid);
 	printk(KERN_DEBUG "  ");
 	for (pfn = start; pfn < end; pfn += PAGES_PER_ELEMENT) {
 		physnode_map[pfn / PAGES_PER_ELEMENT] = nid;
 		printk("%ld ", pfn);
 	}
 	printk("\n");
 }

 unsigned long node_memmap_size_bytes(int nid, unsigned long start_pfn,
 					      unsigned long end_pfn)
 {
 	unsigned long nr_pages = end_pfn - start_pfn;

 	if (!nr_pages)
 		return 0;

 	return (nr_pages + 1) * sizeof(struct page);
 }
 #endif

 extern unsigned long find_max_low_pfn(void);
 extern void add_one_highpage_init(struct page *, int, int);
 extern unsigned long highend_pfn, highstart_pfn;

 #define LARGE_PAGE_BYTES (PTRS_PER_PTE * PAGE_SIZE)

 unsigned long node_remap_size[MAX_NUMNODES];
 static void *node_remap_start_vaddr[MAX_NUMNODES];
 void set_pmd_pfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags);

 static unsigned long kva_start_pfn;
 static unsigned long kva_pages;
 /*
  * FLAT - support for basic PC memory model with discontig enabled, essentially
  *        a single node with all available processors in it with a flat
  *        memory map.
  */
 int __init get_memcfg_numa_flat(void)
 {
 	printk("NUMA - single node, flat memory mode\n");

 	/* Run the memory configuration and find the top of memory. */
 	propagate_e820_map();
 	node_start_pfn[0] = 0;
 	node_end_pfn[0] = max_pfn;
 	memory_present(0, 0, max_pfn);

         /* Indicate there is one node available. */
 	nodes_clear(node_online_map);
 	node_set_online(0);
 	return 1;
 }

 /*
  * Find the highest page frame number we have available for the node
  */
 static void __init propagate_e820_map_node(int nid)
 {
 	if (node_end_pfn[nid] > max_pfn)
 		node_end_pfn[nid] = max_pfn;
 	/*
 	 * if a user has given mem=XXXX, then we need to make sure
 	 * that the node _starts_ before that, too, not just ends
 	 */
 	if (node_start_pfn[nid] > max_pfn)
 		node_start_pfn[nid] = max_pfn;
 	BUG_ON(node_start_pfn[nid] > node_end_pfn[nid]);
 }

 /*
  * Allocate memory for the pg_data_t for this node via a crude pre-bootmem
  * method.  For node zero take this from the bottom of memory, for
  * subsequent nodes place them at node_remap_start_vaddr which contains
  * node local data in physically node local memory.  See setup_memory()
  * for details.
  */
 static void __init allocate_pgdat(int nid)
 {
 	if (nid && node_has_online_mem(nid))
 		NODE_DATA(nid) = (pg_data_t *)node_remap_start_vaddr[nid];
 	else {
 		NODE_DATA(nid) = (pg_data_t *)(pfn_to_kaddr(min_low_pfn));
 		min_low_pfn += PFN_UP(sizeof(pg_data_t));
 	}
 }

 #ifdef CONFIG_DISCONTIGMEM
 /*
  * In the discontig memory model, a portion of the kernel virtual area (KVA)
  * is reserved and portions of nodes are mapped using it. This is to allow
  * node-local memory to be allocated for structures that would normally require
  * ZONE_NORMAL. The memory is allocated with alloc_remap() and callers
  * should be prepared to allocate from the bootmem allocator instead. This KVA
  * mechanism is incompatible with SPARSEMEM as it makes assumptions about the
  * layout of memory that are broken if alloc_remap() succeeds for some of the
  * map and fails for others
  */
 static unsigned long node_remap_start_pfn[MAX_NUMNODES];
 static void *node_remap_end_vaddr[MAX_NUMNODES];
 static void *node_remap_alloc_vaddr[MAX_NUMNODES];
 static unsigned long node_remap_offset[MAX_NUMNODES];

 void *alloc_remap(int nid, unsigned long size)
 {
 	void *allocation = node_remap_alloc_vaddr[nid];

 	size = ALIGN(size, L1_CACHE_BYTES);

 	if (!allocation || (allocation + size) >= node_remap_end_vaddr[nid])
 		return 0;

 	node_remap_alloc_vaddr[nid] += size;
 	memset(allocation, 0, size);

 	return allocation;
 }

 void __init remap_numa_kva(void)
 {
 	void *vaddr;
 	unsigned long pfn;
 	int node;

 	for_each_online_node(node) {
 		for (pfn=0; pfn < node_remap_size[node]; pfn += PTRS_PER_PTE) {
 			vaddr = node_remap_start_vaddr[node]+(pfn<<PAGE_SHIFT);
 			set_pmd_pfn((ulong) vaddr,
 				node_remap_start_pfn[node] + pfn,
 				PAGE_KERNEL_LARGE);
 		}
 	}
 }

 static unsigned long calculate_numa_remap_pages(void)
 {
 	int nid;
 	unsigned long size, reserve_pages = 0;
 	unsigned long pfn;

 	for_each_online_node(nid) {
 		unsigned old_end_pfn = node_end_pfn[nid];

 		/*
 		 * The acpi/srat node info can show hot-add memroy zones
 		 * where memory could be added but not currently present.
 		 */
 		if (node_start_pfn[nid] > max_pfn)
 			continue;
 		if (node_end_pfn[nid] > max_pfn)
 			node_end_pfn[nid] = max_pfn;

 		/* ensure the remap includes space for the pgdat. */
 		size = node_remap_size[nid] + sizeof(pg_data_t);

 		/* convert size to large (pmd size) pages, rounding up */
 		size = (size + LARGE_PAGE_BYTES - 1) / LARGE_PAGE_BYTES;
 		/* now the roundup is correct, convert to PAGE_SIZE pages */
 		size = size * PTRS_PER_PTE;

 		/*
 		 * Validate the region we are allocating only contains valid
 		 * pages.
 		 */
 		for (pfn = node_end_pfn[nid] - size;
 		     pfn < node_end_pfn[nid]; pfn++)
 			if (!page_is_ram(pfn))
 				break;

 		if (pfn != node_end_pfn[nid])
 			size = 0;

 		printk("Reserving %ld pages of KVA for lmem_map of node %d\n",
 				size, nid);
 		node_remap_size[nid] = size;
 		node_remap_offset[nid] = reserve_pages;
 		reserve_pages += size;
 		printk("Shrinking node %d from %ld pages to %ld pages\n",
 			nid, node_end_pfn[nid], node_end_pfn[nid] - size);

 		if (node_end_pfn[nid] & (PTRS_PER_PTE-1)) {
 			/*
 			 * Align node_end_pfn[] and node_remap_start_pfn[] to
 			 * pmd boundary. remap_numa_kva will barf otherwise.
 			 */
 			printk("Shrinking node %d further by %ld pages for proper alignment\n",
 				nid, node_end_pfn[nid] & (PTRS_PER_PTE-1));
 			size +=  node_end_pfn[nid] & (PTRS_PER_PTE-1);
 		}

 		node_end_pfn[nid] -= size;
 		node_remap_start_pfn[nid] = node_end_pfn[nid];
 		shrink_active_range(nid, old_end_pfn, node_end_pfn[nid]);
 	}
 	printk("Reserving total of %ld pages for numa KVA remap\n",
 			reserve_pages);
 	return reserve_pages;
 }

 static void init_remap_allocator(int nid)
 {
 	node_remap_start_vaddr[nid] = pfn_to_kaddr(
 			kva_start_pfn + node_remap_offset[nid]);
 	node_remap_end_vaddr[nid] = node_remap_start_vaddr[nid] +
 		(node_remap_size[nid] * PAGE_SIZE);
 	node_remap_alloc_vaddr[nid] = node_remap_start_vaddr[nid] +
 		ALIGN(sizeof(pg_data_t), PAGE_SIZE);

 	printk ("node %d will remap to vaddr %08lx - %08lx\n", nid,
 		(ulong) node_remap_start_vaddr[nid],
 		(ulong) pfn_to_kaddr(highstart_pfn
 		   + node_remap_offset[nid] + node_remap_size[nid]));
 }
 #else
 void *alloc_remap(int nid, unsigned long size)
 {
 	return NULL;
 }

 static unsigned long calculate_numa_remap_pages(void)
 {
 	return 0;
 }

 static void init_remap_allocator(int nid)
 {
 }

 void __init remap_numa_kva(void)
 {
 }
 #endif /* CONFIG_DISCONTIGMEM */

 extern void setup_bootmem_allocator(void);
 unsigned long __init setup_memory(void)
 {
 	int nid;
 	unsigned long system_start_pfn, system_max_low_pfn;
 	unsigned long wasted_pages;

 	/*
 	 * When mapping a NUMA machine we allocate the node_mem_map arrays
 	 * from node local memory.  They are then mapped directly into KVA
 	 * between zone normal and vmalloc space.  Calculate the size of
 	 * this space and use it to adjust the boundary between ZONE_NORMAL
 	 * and ZONE_HIGHMEM.
 	 */
 	get_memcfg_numa();

 	kva_pages = calculate_numa_remap_pages();

 	/* partially used pages are not usable - thus round upwards */
 	system_start_pfn = min_low_pfn = PFN_UP(init_pg_tables_end);

 	kva_start_pfn = find_max_low_pfn() - kva_pages;

 #ifdef CONFIG_BLK_DEV_INITRD
 	/* Numa kva area is below the initrd */
 	if (initrd_start)
 		kva_start_pfn = PFN_DOWN(initrd_start - PAGE_OFFSET)
 			- kva_pages;
 #endif

 	/*
 	 * We waste pages past at the end of the KVA for no good reason other
 	 * than how it is located. This is bad.
 	 */
 	wasted_pages = kva_start_pfn & (PTRS_PER_PTE-1);
 	kva_start_pfn -= wasted_pages;
 	kva_pages += wasted_pages;

 	system_max_low_pfn = max_low_pfn = find_max_low_pfn();
 	printk("kva_start_pfn ~ %ld find_max_low_pfn() ~ %ld\n",
 		kva_start_pfn, max_low_pfn);
 	printk("max_pfn = %ld\n", max_pfn);
 #ifdef CONFIG_HIGHMEM
 	highstart_pfn = highend_pfn = max_pfn;
 	if (max_pfn > system_max_low_pfn)
 		highstart_pfn = system_max_low_pfn;
 	printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
 	       pages_to_mb(highend_pfn - highstart_pfn));
 	num_physpages = highend_pfn;
 	high_memory = (void *) __va(highstart_pfn * PAGE_SIZE - 1) + 1;
 #else
 	num_physpages = system_max_low_pfn;
 	high_memory = (void *) __va(system_max_low_pfn * PAGE_SIZE - 1) + 1;
 #endif
 	printk(KERN_NOTICE "%ldMB LOWMEM available.\n",
 			pages_to_mb(system_max_low_pfn));
 	printk("min_low_pfn = %ld, max_low_pfn = %ld, highstart_pfn = %ld\n",
 			min_low_pfn, max_low_pfn, highstart_pfn);

 	printk("Low memory ends at vaddr %08lx\n",
 			(ulong) pfn_to_kaddr(max_low_pfn));
 	for_each_online_node(nid) {
 		init_remap_allocator(nid);

 		allocate_pgdat(nid);
 	}
 	printk("High memory starts at vaddr %08lx\n",
 			(ulong) pfn_to_kaddr(highstart_pfn));
 	for_each_online_node(nid)
 		propagate_e820_map_node(nid);

 	memset(NODE_DATA(0), 0, sizeof(struct pglist_data));
 	NODE_DATA(0)->bdata = &node0_bdata;
 	setup_bootmem_allocator();
 	return max_low_pfn;
 }

 void __init numa_kva_reserve(void)
 {
 	if (kva_pages)
 		reserve_bootmem(PFN_PHYS(kva_start_pfn), PFN_PHYS(kva_pages),
 				BOOTMEM_DEFAULT);
 }

 void __init zone_sizes_init(void)
 {
 	int nid;
 	unsigned long max_zone_pfns[MAX_NR_ZONES];
 	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
 	max_zone_pfns[ZONE_DMA] =
 		virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
 	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
 #ifdef CONFIG_HIGHMEM
 	max_zone_pfns[ZONE_HIGHMEM] = highend_pfn;
 #endif

 	/* If SRAT has not registered memory, register it now */
 	if (find_max_pfn_with_active_regions() == 0) {
 		for_each_online_node(nid) {
 			if (node_has_online_mem(nid))
 				add_active_range(nid, node_start_pfn[nid],
 							node_end_pfn[nid]);
 		}
 	}

 	free_area_init_nodes(max_zone_pfns);
 	return;
 }

 void __init set_highmem_pages_init(int bad_ppro)
 {
 #ifdef CONFIG_HIGHMEM
 	struct zone *zone;
 	struct page *page;

 	for_each_zone(zone) {
 		unsigned long node_pfn, zone_start_pfn, zone_end_pfn;

 		if (!is_highmem(zone))
 			continue;

 		zone_start_pfn = zone->zone_start_pfn;
 		zone_end_pfn = zone_start_pfn + zone->spanned_pages;

 		printk("Initializing %s for node %d (%08lx:%08lx)\n",
 				zone->name, zone_to_nid(zone),
 				zone_start_pfn, zone_end_pfn);

 		for (node_pfn = zone_start_pfn; node_pfn < zone_end_pfn; node_pfn++) {
 			if (!pfn_valid(node_pfn))
 				continue;
 			page = pfn_to_page(node_pfn);
 			add_one_highpage_init(page, node_pfn, bad_ppro);
 		}
 	}
 	totalram_pages += totalhigh_pages;
 #endif
 }

 #ifdef CONFIG_MEMORY_HOTPLUG
 static int paddr_to_nid(u64 addr)
 {
 	int nid;
 	unsigned long pfn = PFN_DOWN(addr);

 	for_each_node(nid)
 		if (node_start_pfn[nid] <= pfn &&
 		    pfn < node_end_pfn[nid])
 			return nid;

 	return -1;
 }

 /*
  * This function is used to ask node id BEFORE memmap and mem_section's
  * initialization (pfn_to_nid() can't be used yet).
  * If _PXM is not defined on ACPI's DSDT, node id must be found by this.
  */
 int memory_add_physaddr_to_nid(u64 addr)
 {
 	int nid = paddr_to_nid(addr);
 	return (nid >= 0) ? nid : 0;
 }

 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
 #endif
	/*
	* Written by: Patricia Gaughen <gone@us.ibm.com>, IBM Corporation
	* August 2002: added remote node KVA remap - Martin J. Bligh
	*
	* Copyright (C) 2002, IBM Corp.
	*
	* All rights reserved.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful, but
	* WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
	* NON INFRINGEMENT. See the GNU General Public License for more
	* details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	*/

	#include <linux/mm.h>
	#include <linux/bootmem.h>
	#include <linux/mmzone.h>
	#include <linux/highmem.h>
	#include <linux/initrd.h>
	#include <linux/nodemask.h>
	#include <linux/module.h>
	#include <linux/kexec.h>
	#include <linux/pfn.h>
	#include <linux/swap.h>
	#include <linux/acpi.h>

	#include <asm/e820.h>
	#include <asm/setup.h>
	#include <asm/mmzone.h>
	#include <asm/bios_ebda.h>

	struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
	EXPORT_SYMBOL(node_data);
	static bootmem_data_t node0_bdata;

	/*
	* numa interface - we expect the numa architecture specific code to have
	* populated the following initialisation.
	*
	* 1) node_online_map - the map of all nodes configured (online) in the system
	* 2) node_start_pfn - the starting page frame number for a node
	* 3) node_end_pfn - the ending page fram number for a node
	*/
	unsigned long node_start_pfn[MAX_NUMNODES] __read_mostly;
	unsigned long node_end_pfn[MAX_NUMNODES] __read_mostly;


	#ifdef CONFIG_DISCONTIGMEM
	/*
	* 4) physnode_map - the mapping between a pfn and owning node
	* physnode_map keeps track of the physical memory layout of a generic
	* numa node on a 256Mb break (each element of the array will
	* represent 256Mb of memory and will be marked by the node id. so,
	* if the first gig is on node 0, and the second gig is on node 1
	* physnode_map will contain:
	*
	* physnode_map[0-3] = 0;
	* physnode_map[4-7] = 1;
	* physnode_map[8- ] = -1;
	*/
	s8 physnode_map[MAX_ELEMENTS] __read_mostly = { [0 ... (MAX_ELEMENTS - 1)] = -1};
	EXPORT_SYMBOL(physnode_map);

	void memory_present(int nid, unsigned long start, unsigned long end)
	{
	unsigned long pfn;

	printk(KERN_INFO "Node: %d, start_pfn: %ld, end_pfn: %ld\n",
	nid, start, end);
	printk(KERN_DEBUG " Setting physnode_map array to node %d for pfns:\n", nid);
	printk(KERN_DEBUG " ");
	for (pfn = start; pfn < end; pfn += PAGES_PER_ELEMENT) {
	physnode_map[pfn / PAGES_PER_ELEMENT] = nid;
	printk("%ld ", pfn);
	}
	printk("\n");
	}

	unsigned long node_memmap_size_bytes(int nid, unsigned long start_pfn,
	unsigned long end_pfn)
	{
	unsigned long nr_pages = end_pfn - start_pfn;

	if (!nr_pages)
	return 0;

	return (nr_pages + 1) * sizeof(struct page);
	}
	#endif

	extern unsigned long find_max_low_pfn(void);
	extern void add_one_highpage_init(struct page *, int, int);
	extern unsigned long highend_pfn, highstart_pfn;

	#define LARGE_PAGE_BYTES (PTRS_PER_PTE * PAGE_SIZE)

	unsigned long node_remap_size[MAX_NUMNODES];
	static void *node_remap_start_vaddr[MAX_NUMNODES];
	void set_pmd_pfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags);

	static unsigned long kva_start_pfn;
	static unsigned long kva_pages;
	/*
	* FLAT - support for basic PC memory model with discontig enabled, essentially
	* a single node with all available processors in it with a flat
	* memory map.
	*/
	int __init get_memcfg_numa_flat(void)
	{
	printk("NUMA - single node, flat memory mode\n");

	/* Run the memory configuration and find the top of memory. */
	propagate_e820_map();
	node_start_pfn[0] = 0;
	node_end_pfn[0] = max_pfn;
	memory_present(0, 0, max_pfn);

	/* Indicate there is one node available. */
	nodes_clear(node_online_map);
	node_set_online(0);
	return 1;
	}

	/*
	* Find the highest page frame number we have available for the node
	*/
	static void __init propagate_e820_map_node(int nid)
	{
	if (node_end_pfn[nid] > max_pfn)
	node_end_pfn[nid] = max_pfn;
	/*
	* if a user has given mem=XXXX, then we need to make sure
	* that the node _starts_ before that, too, not just ends
	*/
	if (node_start_pfn[nid] > max_pfn)
	node_start_pfn[nid] = max_pfn;
	BUG_ON(node_start_pfn[nid] > node_end_pfn[nid]);
	}

	/*
	* Allocate memory for the pg_data_t for this node via a crude pre-bootmem
	* method. For node zero take this from the bottom of memory, for
	* subsequent nodes place them at node_remap_start_vaddr which contains
	* node local data in physically node local memory. See setup_memory()
	* for details.
	*/
	static void __init allocate_pgdat(int nid)
	{
	if (nid && node_has_online_mem(nid))
	NODE_DATA(nid) = (pg_data_t *)node_remap_start_vaddr[nid];
	else {
	NODE_DATA(nid) = (pg_data_t *)(pfn_to_kaddr(min_low_pfn));
	min_low_pfn += PFN_UP(sizeof(pg_data_t));
	}
	}

	#ifdef CONFIG_DISCONTIGMEM
	/*
	* In the discontig memory model, a portion of the kernel virtual area (KVA)
	* is reserved and portions of nodes are mapped using it. This is to allow
	* node-local memory to be allocated for structures that would normally require
	* ZONE_NORMAL. The memory is allocated with alloc_remap() and callers
	* should be prepared to allocate from the bootmem allocator instead. This KVA
	* mechanism is incompatible with SPARSEMEM as it makes assumptions about the
	* layout of memory that are broken if alloc_remap() succeeds for some of the
	* map and fails for others
	*/
	static unsigned long node_remap_start_pfn[MAX_NUMNODES];
	static void *node_remap_end_vaddr[MAX_NUMNODES];
	static void *node_remap_alloc_vaddr[MAX_NUMNODES];
	static unsigned long node_remap_offset[MAX_NUMNODES];

	void *alloc_remap(int nid, unsigned long size)
	{
	void *allocation = node_remap_alloc_vaddr[nid];

	size = ALIGN(size, L1_CACHE_BYTES);

	if (!allocation \|\| (allocation + size) >= node_remap_end_vaddr[nid])
	return 0;

	node_remap_alloc_vaddr[nid] += size;
	memset(allocation, 0, size);

	return allocation;
	}

	void __init remap_numa_kva(void)
	{
	void *vaddr;
	unsigned long pfn;
	int node;

	for_each_online_node(node) {
	for (pfn=0; pfn < node_remap_size[node]; pfn += PTRS_PER_PTE) {
	vaddr = node_remap_start_vaddr[node]+(pfn<<PAGE_SHIFT);
	set_pmd_pfn((ulong) vaddr,
	node_remap_start_pfn[node] + pfn,
	PAGE_KERNEL_LARGE);
	}
	}
	}

	static unsigned long calculate_numa_remap_pages(void)
	{
	int nid;
	unsigned long size, reserve_pages = 0;
	unsigned long pfn;

	for_each_online_node(nid) {
	unsigned old_end_pfn = node_end_pfn[nid];

	/*
	* The acpi/srat node info can show hot-add memroy zones
	* where memory could be added but not currently present.
	*/
	if (node_start_pfn[nid] > max_pfn)
	continue;
	if (node_end_pfn[nid] > max_pfn)
	node_end_pfn[nid] = max_pfn;

	/* ensure the remap includes space for the pgdat. */
	size = node_remap_size[nid] + sizeof(pg_data_t);

	/* convert size to large (pmd size) pages, rounding up */
	size = (size + LARGE_PAGE_BYTES - 1) / LARGE_PAGE_BYTES;
	/* now the roundup is correct, convert to PAGE_SIZE pages */
	size = size * PTRS_PER_PTE;

	/*
	* Validate the region we are allocating only contains valid
	* pages.
	*/
	for (pfn = node_end_pfn[nid] - size;
	pfn < node_end_pfn[nid]; pfn++)
	if (!page_is_ram(pfn))
	break;

	if (pfn != node_end_pfn[nid])
	size = 0;

	printk("Reserving %ld pages of KVA for lmem_map of node %d\n",
	size, nid);
	node_remap_size[nid] = size;
	node_remap_offset[nid] = reserve_pages;
	reserve_pages += size;
	printk("Shrinking node %d from %ld pages to %ld pages\n",
	nid, node_end_pfn[nid], node_end_pfn[nid] - size);

	if (node_end_pfn[nid] & (PTRS_PER_PTE-1)) {
	/*
	* Align node_end_pfn[] and node_remap_start_pfn[] to
	* pmd boundary. remap_numa_kva will barf otherwise.
	*/
	printk("Shrinking node %d further by %ld pages for proper alignment\n",
	nid, node_end_pfn[nid] & (PTRS_PER_PTE-1));
	size += node_end_pfn[nid] & (PTRS_PER_PTE-1);
	}

	node_end_pfn[nid] -= size;
	node_remap_start_pfn[nid] = node_end_pfn[nid];
	shrink_active_range(nid, old_end_pfn, node_end_pfn[nid]);
	}
	printk("Reserving total of %ld pages for numa KVA remap\n",
	reserve_pages);
	return reserve_pages;
	}

	static void init_remap_allocator(int nid)
	{
	node_remap_start_vaddr[nid] = pfn_to_kaddr(
	kva_start_pfn + node_remap_offset[nid]);
	node_remap_end_vaddr[nid] = node_remap_start_vaddr[nid] +
	(node_remap_size[nid] * PAGE_SIZE);
	node_remap_alloc_vaddr[nid] = node_remap_start_vaddr[nid] +
	ALIGN(sizeof(pg_data_t), PAGE_SIZE);

	printk ("node %d will remap to vaddr %08lx - %08lx\n", nid,
	(ulong) node_remap_start_vaddr[nid],
	(ulong) pfn_to_kaddr(highstart_pfn
	+ node_remap_offset[nid] + node_remap_size[nid]));
	}
	#else
	void *alloc_remap(int nid, unsigned long size)
	{
	return NULL;
	}

	static unsigned long calculate_numa_remap_pages(void)
	{
	return 0;
	}

	static void init_remap_allocator(int nid)
	{
	}

	void __init remap_numa_kva(void)
	{
	}
	#endif /* CONFIG_DISCONTIGMEM */

	extern void setup_bootmem_allocator(void);
	unsigned long __init setup_memory(void)
	{
	int nid;
	unsigned long system_start_pfn, system_max_low_pfn;
	unsigned long wasted_pages;

	/*
	* When mapping a NUMA machine we allocate the node_mem_map arrays
	* from node local memory. They are then mapped directly into KVA
	* between zone normal and vmalloc space. Calculate the size of
	* this space and use it to adjust the boundary between ZONE_NORMAL
	* and ZONE_HIGHMEM.
	*/
	get_memcfg_numa();

	kva_pages = calculate_numa_remap_pages();

	/* partially used pages are not usable - thus round upwards */
	system_start_pfn = min_low_pfn = PFN_UP(init_pg_tables_end);

	kva_start_pfn = find_max_low_pfn() - kva_pages;

	#ifdef CONFIG_BLK_DEV_INITRD
	/* Numa kva area is below the initrd */
	if (initrd_start)
	kva_start_pfn = PFN_DOWN(initrd_start - PAGE_OFFSET)
	- kva_pages;
	#endif

	/*
	* We waste pages past at the end of the KVA for no good reason other
	* than how it is located. This is bad.
	*/
	wasted_pages = kva_start_pfn & (PTRS_PER_PTE-1);
	kva_start_pfn -= wasted_pages;
	kva_pages += wasted_pages;

	system_max_low_pfn = max_low_pfn = find_max_low_pfn();
	printk("kva_start_pfn ~ %ld find_max_low_pfn() ~ %ld\n",
	kva_start_pfn, max_low_pfn);
	printk("max_pfn = %ld\n", max_pfn);
	#ifdef CONFIG_HIGHMEM
	highstart_pfn = highend_pfn = max_pfn;
	if (max_pfn > system_max_low_pfn)
	highstart_pfn = system_max_low_pfn;
	printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
	pages_to_mb(highend_pfn - highstart_pfn));
	num_physpages = highend_pfn;
	high_memory = (void ) __va(highstart_pfn PAGE_SIZE - 1) + 1;
	#else
	num_physpages = system_max_low_pfn;
	high_memory = (void ) __va(system_max_low_pfn PAGE_SIZE - 1) + 1;
	#endif
	printk(KERN_NOTICE "%ldMB LOWMEM available.\n",
	pages_to_mb(system_max_low_pfn));
	printk("min_low_pfn = %ld, max_low_pfn = %ld, highstart_pfn = %ld\n",
	min_low_pfn, max_low_pfn, highstart_pfn);

	printk("Low memory ends at vaddr %08lx\n",
	(ulong) pfn_to_kaddr(max_low_pfn));
	for_each_online_node(nid) {
	init_remap_allocator(nid);

	allocate_pgdat(nid);
	}
	printk("High memory starts at vaddr %08lx\n",
	(ulong) pfn_to_kaddr(highstart_pfn));
	for_each_online_node(nid)
	propagate_e820_map_node(nid);

	memset(NODE_DATA(0), 0, sizeof(struct pglist_data));
	NODE_DATA(0)->bdata = &node0_bdata;
	setup_bootmem_allocator();
	return max_low_pfn;
	}

	void __init numa_kva_reserve(void)
	{
	if (kva_pages)
	reserve_bootmem(PFN_PHYS(kva_start_pfn), PFN_PHYS(kva_pages),
	BOOTMEM_DEFAULT);
	}

	void __init zone_sizes_init(void)
	{
	int nid;
	unsigned long max_zone_pfns[MAX_NR_ZONES];
	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
	max_zone_pfns[ZONE_DMA] =
	virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
	#ifdef CONFIG_HIGHMEM
	max_zone_pfns[ZONE_HIGHMEM] = highend_pfn;
	#endif

	/* If SRAT has not registered memory, register it now */
	if (find_max_pfn_with_active_regions() == 0) {
	for_each_online_node(nid) {
	if (node_has_online_mem(nid))
	add_active_range(nid, node_start_pfn[nid],
	node_end_pfn[nid]);
	}
	}

	free_area_init_nodes(max_zone_pfns);
	return;
	}

	void __init set_highmem_pages_init(int bad_ppro)
	{
	#ifdef CONFIG_HIGHMEM
	struct zone *zone;
	struct page *page;

	for_each_zone(zone) {
	unsigned long node_pfn, zone_start_pfn, zone_end_pfn;

	if (!is_highmem(zone))
	continue;

	zone_start_pfn = zone->zone_start_pfn;
	zone_end_pfn = zone_start_pfn + zone->spanned_pages;

	printk("Initializing %s for node %d (%08lx:%08lx)\n",
	zone->name, zone_to_nid(zone),
	zone_start_pfn, zone_end_pfn);

	for (node_pfn = zone_start_pfn; node_pfn < zone_end_pfn; node_pfn++) {
	if (!pfn_valid(node_pfn))
	continue;
	page = pfn_to_page(node_pfn);
	add_one_highpage_init(page, node_pfn, bad_ppro);
	}
	}
	totalram_pages += totalhigh_pages;
	#endif
	}

	#ifdef CONFIG_MEMORY_HOTPLUG
	static int paddr_to_nid(u64 addr)
	{
	int nid;
	unsigned long pfn = PFN_DOWN(addr);

	for_each_node(nid)
	if (node_start_pfn[nid] <= pfn &&
	pfn < node_end_pfn[nid])
	return nid;

	return -1;
	}

	/*
	* This function is used to ask node id BEFORE memmap and mem_section's
	* initialization (pfn_to_nid() can't be used yet).
	* If _PXM is not defined on ACPI's DSDT, node id must be found by this.
	*/
	int memory_add_physaddr_to_nid(u64 addr)
	{
	int nid = paddr_to_nid(addr);
	return (nid >= 0) ? nid : 0;
	}

	EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
	#endif