Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 737 insertions, 0 deletions

diff --git a/arch/ia64/mm/discontig.c b/arch/ia64/mm/discontig.c
new file mode 100644
index 00000000000..3456a9b6971
--- /dev/null
+++ b/arch/ia64/mm/discontig.c
@@ -0,0 +1,737 @@
+/*
+ * Copyright (c) 2000, 2003 Silicon Graphics, Inc.  All rights reserved.
+ * Copyright (c) 2001 Intel Corp.
+ * Copyright (c) 2001 Tony Luck <tony.luck@intel.com>
+ * Copyright (c) 2002 NEC Corp.
+ * Copyright (c) 2002 Kimio Suganuma <k-suganuma@da.jp.nec.com>
+ * Copyright (c) 2004 Silicon Graphics, Inc
+ *	Russ Anderson <rja@sgi.com>
+ *	Jesse Barnes <jbarnes@sgi.com>
+ *	Jack Steiner <steiner@sgi.com>
+ */
+
+/*
+ * Platform initialization for Discontig Memory
+ */
+
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/bootmem.h>
+#include <linux/acpi.h>
+#include <linux/efi.h>
+#include <linux/nodemask.h>
+#include <asm/pgalloc.h>
+#include <asm/tlb.h>
+#include <asm/meminit.h>
+#include <asm/numa.h>
+#include <asm/sections.h>
+
+/*
+ * Track per-node information needed to setup the boot memory allocator, the
+ * per-node areas, and the real VM.
+ */
+struct early_node_data {
+	struct ia64_node_data *node_data;
+	pg_data_t *pgdat;
+	unsigned long pernode_addr;
+	unsigned long pernode_size;
+	struct bootmem_data bootmem_data;
+	unsigned long num_physpages;
+	unsigned long num_dma_physpages;
+	unsigned long min_pfn;
+	unsigned long max_pfn;
+};
+
+static struct early_node_data mem_data[MAX_NUMNODES] __initdata;
+
+/**
+ * reassign_cpu_only_nodes - called from find_memory to move CPU-only nodes to a memory node
+ *
+ * This function will move nodes with only CPUs (no memory)
+ * to a node with memory which is at the minimum numa_slit distance.
+ * Any reassigments will result in the compression of the nodes
+ * and renumbering the nid values where appropriate.
+ * The static declarations below are to avoid large stack size which
+ * makes the code not re-entrant.
+ */
+static void __init reassign_cpu_only_nodes(void)
+{
+	struct node_memblk_s *p;
+	int i, j, k, nnode, nid, cpu, cpunid, pxm;
+	u8 cslit, slit;
+	static DECLARE_BITMAP(nodes_with_mem, MAX_NUMNODES) __initdata;
+	static u8 numa_slit_fix[MAX_NUMNODES * MAX_NUMNODES] __initdata;
+	static int node_flip[MAX_NUMNODES] __initdata;
+	static int old_nid_map[NR_CPUS] __initdata;
+
+	for (nnode = 0, p = &node_memblk[0]; p < &node_memblk[num_node_memblks]; p++)
+		if (!test_bit(p->nid, (void *) nodes_with_mem)) {
+			set_bit(p->nid, (void *) nodes_with_mem);
+			nnode++;
+		}
+
+	/*
+	 * All nids with memory.
+	 */
+	if (nnode == num_online_nodes())
+		return;
+
+	/*
+	 * Change nids and attempt to migrate CPU-only nodes
+	 * to the best numa_slit (closest neighbor) possible.
+	 * For reassigned CPU nodes a nid can't be arrived at
+	 * until after this loop because the target nid's new
+	 * identity might not have been established yet. So
+	 * new nid values are fabricated above num_online_nodes() and
+	 * mapped back later to their true value.
+	 */
+	/* MCD - This code is a bit complicated, but may be unnecessary now.
+	 * We can now handle much more interesting node-numbering.
+	 * The old requirement that 0 <= nid <= numnodes <= MAX_NUMNODES
+	 * and that there be no holes in the numbering 0..numnodes
+	 * has become simply 0 <= nid <= MAX_NUMNODES.
+	 */
+	nid = 0;
+	for_each_online_node(i)  {
+		if (test_bit(i, (void *) nodes_with_mem)) {
+			/*
+			 * Save original nid value for numa_slit
+			 * fixup and node_cpuid reassignments.
+			 */
+			node_flip[nid] = i;
+
+			if (i == nid) {
+				nid++;
+				continue;
+			}
+
+			for (p = &node_memblk[0]; p < &node_memblk[num_node_memblks]; p++)
+				if (p->nid == i)
+					p->nid = nid;
+
+			cpunid = nid;
+			nid++;
+		} else
+			cpunid = MAX_NUMNODES;
+
+		for (cpu = 0; cpu < NR_CPUS; cpu++)
+			if (node_cpuid[cpu].nid == i) {
+				/*
+				 * For nodes not being reassigned just
+				 * fix the cpu's nid and reverse pxm map
+				 */
+				if (cpunid < MAX_NUMNODES) {
+					pxm = nid_to_pxm_map[i];
+					pxm_to_nid_map[pxm] =
+					          node_cpuid[cpu].nid = cpunid;
+					continue;
+				}
+
+				/*
+				 * For nodes being reassigned, find best node by
+				 * numa_slit information and then make a temporary
+				 * nid value based on current nid and num_online_nodes().
+				 */
+				slit = 0xff;
+				k = 2*num_online_nodes();
+				for_each_online_node(j) {
+					if (i == j)
+						continue;
+					else if (test_bit(j, (void *) nodes_with_mem)) {
+						cslit = numa_slit[i * num_online_nodes() + j];
+						if (cslit < slit) {
+							k = num_online_nodes() + j;
+							slit = cslit;
+						}
+					}
+				}
+
+				/* save old nid map so we can update the pxm */
+				old_nid_map[cpu] = node_cpuid[cpu].nid;
+				node_cpuid[cpu].nid = k;
+			}
+	}
+
+	/*
+	 * Fixup temporary nid values for CPU-only nodes.
+	 */
+	for (cpu = 0; cpu < NR_CPUS; cpu++)
+		if (node_cpuid[cpu].nid == (2*num_online_nodes())) {
+			pxm = nid_to_pxm_map[old_nid_map[cpu]];
+			pxm_to_nid_map[pxm] = node_cpuid[cpu].nid = nnode - 1;
+		} else {
+			for (i = 0; i < nnode; i++) {
+				if (node_flip[i] != (node_cpuid[cpu].nid - num_online_nodes()))
+					continue;
+
+				pxm = nid_to_pxm_map[old_nid_map[cpu]];
+				pxm_to_nid_map[pxm] = node_cpuid[cpu].nid = i;
+				break;
+			}
+		}
+
+	/*
+	 * Fix numa_slit by compressing from larger
+	 * nid array to reduced nid array.
+	 */
+	for (i = 0; i < nnode; i++)
+		for (j = 0; j < nnode; j++)
+			numa_slit_fix[i * nnode + j] =
+				numa_slit[node_flip[i] * num_online_nodes() + node_flip[j]];
+
+	memcpy(numa_slit, numa_slit_fix, sizeof (numa_slit));
+
+	nodes_clear(node_online_map);
+	for (i = 0; i < nnode; i++)
+		node_set_online(i);
+
+	return;
+}
+
+/*
+ * To prevent cache aliasing effects, align per-node structures so that they
+ * start at addresses that are strided by node number.
+ */
+#define NODEDATA_ALIGN(addr, node)						\
+	((((addr) + 1024*1024-1) & ~(1024*1024-1)) + (node)*PERCPU_PAGE_SIZE)
+
+/**
+ * build_node_maps - callback to setup bootmem structs for each node
+ * @start: physical start of range
+ * @len: length of range
+ * @node: node where this range resides
+ *
+ * We allocate a struct bootmem_data for each piece of memory that we wish to
+ * treat as a virtually contiguous block (i.e. each node). Each such block
+ * must start on an %IA64_GRANULE_SIZE boundary, so we round the address down
+ * if necessary.  Any non-existent pages will simply be part of the virtual
+ * memmap.  We also update min_low_pfn and max_low_pfn here as we receive
+ * memory ranges from the caller.
+ */
+static int __init build_node_maps(unsigned long start, unsigned long len,
+				  int node)
+{
+	unsigned long cstart, epfn, end = start + len;
+	struct bootmem_data *bdp = &mem_data[node].bootmem_data;
+
+	epfn = GRANULEROUNDUP(end) >> PAGE_SHIFT;
+	cstart = GRANULEROUNDDOWN(start);
+
+	if (!bdp->node_low_pfn) {
+		bdp->node_boot_start = cstart;
+		bdp->node_low_pfn = epfn;
+	} else {
+		bdp->node_boot_start = min(cstart, bdp->node_boot_start);
+		bdp->node_low_pfn = max(epfn, bdp->node_low_pfn);
+	}
+
+	min_low_pfn = min(min_low_pfn, bdp->node_boot_start>>PAGE_SHIFT);
+	max_low_pfn = max(max_low_pfn, bdp->node_low_pfn);
+
+	return 0;
+}
+
+/**
+ * early_nr_phys_cpus_node - return number of physical cpus on a given node
+ * @node: node to check
+ *
+ * Count the number of physical cpus on @node.  These are cpus that actually
+ * exist.  We can't use nr_cpus_node() yet because
+ * acpi_boot_init() (which builds the node_to_cpu_mask array) hasn't been
+ * called yet.
+ */
+static int early_nr_phys_cpus_node(int node)
+{
+	int cpu, n = 0;
+
+	for (cpu = 0; cpu < NR_CPUS; cpu++)
+		if (node == node_cpuid[cpu].nid)
+			if ((cpu == 0) || node_cpuid[cpu].phys_id)
+				n++;
+
+	return n;
+}
+
+
+/**
+ * early_nr_cpus_node - return number of cpus on a given node
+ * @node: node to check
+ *
+ * Count the number of cpus on @node.  We can't use nr_cpus_node() yet because
+ * acpi_boot_init() (which builds the node_to_cpu_mask array) hasn't been
+ * called yet.  Note that node 0 will also count all non-existent cpus.
+ */
+static int early_nr_cpus_node(int node)
+{
+	int cpu, n = 0;
+
+	for (cpu = 0; cpu < NR_CPUS; cpu++)
+		if (node == node_cpuid[cpu].nid)
+			n++;
+
+	return n;
+}
+
+/**
+ * find_pernode_space - allocate memory for memory map and per-node structures
+ * @start: physical start of range
+ * @len: length of range
+ * @node: node where this range resides
+ *
+ * This routine reserves space for the per-cpu data struct, the list of
+ * pg_data_ts and the per-node data struct.  Each node will have something like
+ * the following in the first chunk of addr. space large enough to hold it.
+ *
+ *    ________________________
+ *   |                        |
+ *   |~~~~~~~~~~~~~~~~~~~~~~~~| <-- NODEDATA_ALIGN(start, node) for the first
+ *   |    PERCPU_PAGE_SIZE *  |     start and length big enough
+ *   |    cpus_on_this_node   | Node 0 will also have entries for all non-existent cpus.
+ *   |------------------------|
+ *   |   local pg_data_t *    |
+ *   |------------------------|
+ *   |  local ia64_node_data  |
+ *   |------------------------|
+ *   |          ???           |
+ *   |________________________|
+ *
+ * Once this space has been set aside, the bootmem maps are initialized.  We
+ * could probably move the allocation of the per-cpu and ia64_node_data space
+ * outside of this function and use alloc_bootmem_node(), but doing it here
+ * is straightforward and we get the alignments we want so...
+ */
+static int __init find_pernode_space(unsigned long start, unsigned long len,
+				     int node)
+{
+	unsigned long epfn, cpu, cpus, phys_cpus;
+	unsigned long pernodesize = 0, pernode, pages, mapsize;
+	void *cpu_data;
+	struct bootmem_data *bdp = &mem_data[node].bootmem_data;
+
+	epfn = (start + len) >> PAGE_SHIFT;
+
+	pages = bdp->node_low_pfn - (bdp->node_boot_start >> PAGE_SHIFT);
+	mapsize = bootmem_bootmap_pages(pages) << PAGE_SHIFT;
+
+	/*
+	 * Make sure this memory falls within this node's usable memory
+	 * since we may have thrown some away in build_maps().
+	 */
+	if (start < bdp->node_boot_start || epfn > bdp->node_low_pfn)
+		return 0;
+
+	/* Don't setup this node's local space twice... */
+	if (mem_data[node].pernode_addr)
+		return 0;
+
+	/*
+	 * Calculate total size needed, incl. what's necessary
+	 * for good alignment and alias prevention.
+	 */
+	cpus = early_nr_cpus_node(node);
+	phys_cpus = early_nr_phys_cpus_node(node);
+	pernodesize += PERCPU_PAGE_SIZE * cpus;
+	pernodesize += node * L1_CACHE_BYTES;
+	pernodesize += L1_CACHE_ALIGN(sizeof(pg_data_t));
+	pernodesize += L1_CACHE_ALIGN(sizeof(struct ia64_node_data));
+	pernodesize = PAGE_ALIGN(pernodesize);
+	pernode = NODEDATA_ALIGN(start, node);
+
+	/* Is this range big enough for what we want to store here? */
+	if (start + len > (pernode + pernodesize + mapsize)) {
+		mem_data[node].pernode_addr = pernode;
+		mem_data[node].pernode_size = pernodesize;
+		memset(__va(pernode), 0, pernodesize);
+
+		cpu_data = (void *)pernode;
+		pernode += PERCPU_PAGE_SIZE * cpus;
+		pernode += node * L1_CACHE_BYTES;
+
+		mem_data[node].pgdat = __va(pernode);
+		pernode += L1_CACHE_ALIGN(sizeof(pg_data_t));
+
+		mem_data[node].node_data = __va(pernode);
+		pernode += L1_CACHE_ALIGN(sizeof(struct ia64_node_data));
+
+		mem_data[node].pgdat->bdata = bdp;
+		pernode += L1_CACHE_ALIGN(sizeof(pg_data_t));
+
+		/*
+		 * Copy the static per-cpu data into the region we
+		 * just set aside and then setup __per_cpu_offset
+		 * for each CPU on this node.
+		 */
+		for (cpu = 0; cpu < NR_CPUS; cpu++) {
+			if (node == node_cpuid[cpu].nid) {
+				memcpy(__va(cpu_data), __phys_per_cpu_start,
+				       __per_cpu_end - __per_cpu_start);
+				__per_cpu_offset[cpu] = (char*)__va(cpu_data) -
+					__per_cpu_start;
+				cpu_data += PERCPU_PAGE_SIZE;
+			}
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * free_node_bootmem - free bootmem allocator memory for use
+ * @start: physical start of range
+ * @len: length of range
+ * @node: node where this range resides
+ *
+ * Simply calls the bootmem allocator to free the specified ranged from
+ * the given pg_data_t's bdata struct.  After this function has been called
+ * for all the entries in the EFI memory map, the bootmem allocator will
+ * be ready to service allocation requests.
+ */
+static int __init free_node_bootmem(unsigned long start, unsigned long len,
+				    int node)
+{
+	free_bootmem_node(mem_data[node].pgdat, start, len);
+
+	return 0;
+}
+
+/**
+ * reserve_pernode_space - reserve memory for per-node space
+ *
+ * Reserve the space used by the bootmem maps & per-node space in the boot
+ * allocator so that when we actually create the real mem maps we don't
+ * use their memory.
+ */
+static void __init reserve_pernode_space(void)
+{
+	unsigned long base, size, pages;
+	struct bootmem_data *bdp;
+	int node;
+
+	for_each_online_node(node) {
+		pg_data_t *pdp = mem_data[node].pgdat;
+
+		bdp = pdp->bdata;
+
+		/* First the bootmem_map itself */
+		pages = bdp->node_low_pfn - (bdp->node_boot_start>>PAGE_SHIFT);
+		size = bootmem_bootmap_pages(pages) << PAGE_SHIFT;
+		base = __pa(bdp->node_bootmem_map);
+		reserve_bootmem_node(pdp, base, size);
+
+		/* Now the per-node space */
+		size = mem_data[node].pernode_size;
+		base = __pa(mem_data[node].pernode_addr);
+		reserve_bootmem_node(pdp, base, size);
+	}
+}
+
+/**
+ * initialize_pernode_data - fixup per-cpu & per-node pointers
+ *
+ * Each node's per-node area has a copy of the global pg_data_t list, so
+ * we copy that to each node here, as well as setting the per-cpu pointer
+ * to the local node data structure.  The active_cpus field of the per-node
+ * structure gets setup by the platform_cpu_init() function later.
+ */
+static void __init initialize_pernode_data(void)
+{
+	int cpu, node;
+	pg_data_t *pgdat_list[MAX_NUMNODES];
+
+	for_each_online_node(node)
+		pgdat_list[node] = mem_data[node].pgdat;
+
+	/* Copy the pg_data_t list to each node and init the node field */
+	for_each_online_node(node) {
+		memcpy(mem_data[node].node_data->pg_data_ptrs, pgdat_list,
+		       sizeof(pgdat_list));
+	}
+
+	/* Set the node_data pointer for each per-cpu struct */
+	for (cpu = 0; cpu < NR_CPUS; cpu++) {
+		node = node_cpuid[cpu].nid;
+		per_cpu(cpu_info, cpu).node_data = mem_data[node].node_data;
+	}
+}
+
+/**
+ * find_memory - walk the EFI memory map and setup the bootmem allocator
+ *
+ * Called early in boot to setup the bootmem allocator, and to
+ * allocate the per-cpu and per-node structures.
+ */
+void __init find_memory(void)
+{
+	int node;
+
+	reserve_memory();
+
+	if (num_online_nodes() == 0) {
+		printk(KERN_ERR "node info missing!\n");
+		node_set_online(0);
+	}
+
+	min_low_pfn = -1;
+	max_low_pfn = 0;
+
+	if (num_online_nodes() > 1)
+		reassign_cpu_only_nodes();
+
+	/* These actually end up getting called by call_pernode_memory() */
+	efi_memmap_walk(filter_rsvd_memory, build_node_maps);
+	efi_memmap_walk(filter_rsvd_memory, find_pernode_space);
+
+	/*
+	 * Initialize the boot memory maps in reverse order since that's
+	 * what the bootmem allocator expects
+	 */
+	for (node = MAX_NUMNODES - 1; node >= 0; node--) {
+		unsigned long pernode, pernodesize, map;
+		struct bootmem_data *bdp;
+
+		if (!node_online(node))
+			continue;
+
+		bdp = &mem_data[node].bootmem_data;
+		pernode = mem_data[node].pernode_addr;
+		pernodesize = mem_data[node].pernode_size;
+		map = pernode + pernodesize;
+
+		/* Sanity check... */
+		if (!pernode)
+			panic("pernode space for node %d "
+			      "could not be allocated!", node);
+
+		init_bootmem_node(mem_data[node].pgdat,
+				  map>>PAGE_SHIFT,
+				  bdp->node_boot_start>>PAGE_SHIFT,
+				  bdp->node_low_pfn);
+	}
+
+	efi_memmap_walk(filter_rsvd_memory, free_node_bootmem);
+
+	reserve_pernode_space();
+	initialize_pernode_data();
+
+	max_pfn = max_low_pfn;
+
+	find_initrd();
+}
+
+/**
+ * per_cpu_init - setup per-cpu variables
+ *
+ * find_pernode_space() does most of this already, we just need to set
+ * local_per_cpu_offset
+ */
+void *per_cpu_init(void)
+{
+	int cpu;
+
+	if (smp_processor_id() == 0) {
+		for (cpu = 0; cpu < NR_CPUS; cpu++) {
+			per_cpu(local_per_cpu_offset, cpu) =
+				__per_cpu_offset[cpu];
+		}
+	}
+
+	return __per_cpu_start + __per_cpu_offset[smp_processor_id()];
+}
+
+/**
+ * show_mem - give short summary of memory stats
+ *
+ * Shows a simple page count of reserved and used pages in the system.
+ * For discontig machines, it does this on a per-pgdat basis.
+ */
+void show_mem(void)
+{
+	int i, total_reserved = 0;
+	int total_shared = 0, total_cached = 0;
+	unsigned long total_present = 0;
+	pg_data_t *pgdat;
+
+	printk("Mem-info:\n");
+	show_free_areas();
+	printk("Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
+	for_each_pgdat(pgdat) {
+		unsigned long present = pgdat->node_present_pages;
+		int shared = 0, cached = 0, reserved = 0;
+		printk("Node ID: %d\n", pgdat->node_id);
+		for(i = 0; i < pgdat->node_spanned_pages; i++) {
+			if (!ia64_pfn_valid(pgdat->node_start_pfn+i))
+				continue;
+			if (PageReserved(pgdat->node_mem_map+i))
+				reserved++;
+			else if (PageSwapCache(pgdat->node_mem_map+i))
+				cached++;
+			else if (page_count(pgdat->node_mem_map+i))
+				shared += page_count(pgdat->node_mem_map+i)-1;
+		}
+		total_present += present;
+		total_reserved += reserved;
+		total_cached += cached;
+		total_shared += shared;
+		printk("\t%ld pages of RAM\n", present);
+		printk("\t%d reserved pages\n", reserved);
+		printk("\t%d pages shared\n", shared);
+		printk("\t%d pages swap cached\n", cached);
+	}
+	printk("%ld pages of RAM\n", total_present);
+	printk("%d reserved pages\n", total_reserved);
+	printk("%d pages shared\n", total_shared);
+	printk("%d pages swap cached\n", total_cached);
+	printk("Total of %ld pages in page table cache\n", pgtable_cache_size);
+	printk("%d free buffer pages\n", nr_free_buffer_pages());
+}
+
+/**
+ * call_pernode_memory - use SRAT to call callback functions with node info
+ * @start: physical start of range
+ * @len: length of range
+ * @arg: function to call for each range
+ *
+ * efi_memmap_walk() knows nothing about layout of memory across nodes. Find
+ * out to which node a block of memory belongs.  Ignore memory that we cannot
+ * identify, and split blocks that run across multiple nodes.
+ *
+ * Take this opportunity to round the start address up and the end address
+ * down to page boundaries.
+ */
+void call_pernode_memory(unsigned long start, unsigned long len, void *arg)
+{
+	unsigned long rs, re, end = start + len;
+	void (*func)(unsigned long, unsigned long, int);
+	int i;
+
+	start = PAGE_ALIGN(start);
+	end &= PAGE_MASK;
+	if (start >= end)
+		return;
+
+	func = arg;
+
+	if (!num_node_memblks) {
+		/* No SRAT table, so assume one node (node 0) */
+		if (start < end)
+			(*func)(start, end - start, 0);
+		return;
+	}
+
+	for (i = 0; i < num_node_memblks; i++) {
+		rs = max(start, node_memblk[i].start_paddr);
+		re = min(end, node_memblk[i].start_paddr +
+			 node_memblk[i].size);
+
+		if (rs < re)
+			(*func)(rs, re - rs, node_memblk[i].nid);
+
+		if (re == end)
+			break;
+	}
+}
+
+/**
+ * count_node_pages - callback to build per-node memory info structures
+ * @start: physical start of range
+ * @len: length of range
+ * @node: node where this range resides
+ *
+ * Each node has it's own number of physical pages, DMAable pages, start, and
+ * end page frame number.  This routine will be called by call_pernode_memory()
+ * for each piece of usable memory and will setup these values for each node.
+ * Very similar to build_maps().
+ */
+static __init int count_node_pages(unsigned long start, unsigned long len, int node)
+{
+	unsigned long end = start + len;
+
+	mem_data[node].num_physpages += len >> PAGE_SHIFT;
+	if (start <= __pa(MAX_DMA_ADDRESS))
+		mem_data[node].num_dma_physpages +=
+			(min(end, __pa(MAX_DMA_ADDRESS)) - start) >>PAGE_SHIFT;
+	start = GRANULEROUNDDOWN(start);
+	start = ORDERROUNDDOWN(start);
+	end = GRANULEROUNDUP(end);
+	mem_data[node].max_pfn = max(mem_data[node].max_pfn,
+				     end >> PAGE_SHIFT);
+	mem_data[node].min_pfn = min(mem_data[node].min_pfn,
+				     start >> PAGE_SHIFT);
+
+	return 0;
+}
+
+/**
+ * paging_init - setup page tables
+ *
+ * paging_init() sets up the page tables for each node of the system and frees
+ * the bootmem allocator memory for general use.
+ */
+void __init paging_init(void)
+{
+	unsigned long max_dma;
+	unsigned long zones_size[MAX_NR_ZONES];
+	unsigned long zholes_size[MAX_NR_ZONES];
+	unsigned long pfn_offset = 0;
+	int node;
+
+	max_dma = virt_to_phys((void *) MAX_DMA_ADDRESS) >> PAGE_SHIFT;
+
+	/* so min() will work in count_node_pages */
+	for_each_online_node(node)
+		mem_data[node].min_pfn = ~0UL;
+
+	efi_memmap_walk(filter_rsvd_memory, count_node_pages);
+
+	for_each_online_node(node) {
+		memset(zones_size, 0, sizeof(zones_size));
+		memset(zholes_size, 0, sizeof(zholes_size));
+
+		num_physpages += mem_data[node].num_physpages;
+
+		if (mem_data[node].min_pfn >= max_dma) {
+			/* All of this node's memory is above ZONE_DMA */
+			zones_size[ZONE_NORMAL] = mem_data[node].max_pfn -
+				mem_data[node].min_pfn;
+			zholes_size[ZONE_NORMAL] = mem_data[node].max_pfn -
+				mem_data[node].min_pfn -
+				mem_data[node].num_physpages;
+		} else if (mem_data[node].max_pfn < max_dma) {
+			/* All of this node's memory is in ZONE_DMA */
+			zones_size[ZONE_DMA] = mem_data[node].max_pfn -
+				mem_data[node].min_pfn;
+			zholes_size[ZONE_DMA] = mem_data[node].max_pfn -
+				mem_data[node].min_pfn -
+				mem_data[node].num_dma_physpages;
+		} else {
+			/* This node has memory in both zones */
+			zones_size[ZONE_DMA] = max_dma -
+				mem_data[node].min_pfn;
+			zholes_size[ZONE_DMA] = zones_size[ZONE_DMA] -
+				mem_data[node].num_dma_physpages;
+			zones_size[ZONE_NORMAL] = mem_data[node].max_pfn -
+				max_dma;
+			zholes_size[ZONE_NORMAL] = zones_size[ZONE_NORMAL] -
+				(mem_data[node].num_physpages -
+				 mem_data[node].num_dma_physpages);
+		}
+
+		if (node == 0) {
+			vmalloc_end -=
+				PAGE_ALIGN(max_low_pfn * sizeof(struct page));
+			vmem_map = (struct page *) vmalloc_end;
+
+			efi_memmap_walk(create_mem_map_page_table, NULL);
+			printk("Virtual mem_map starts at 0x%p\n", vmem_map);
+		}
+
+		pfn_offset = mem_data[node].min_pfn;
+
+		NODE_DATA(node)->node_mem_map = vmem_map + pfn_offset;
+		free_area_init_node(node, NODE_DATA(node), zones_size,
+				    pfn_offset, zholes_size);
+	}
+
+	zero_page_memmap_ptr = virt_to_page(ia64_imva(empty_zero_page));
+}