x86-64, NUMA: Separate out numa_cleanup_meminfo()

[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / arch / x86 / mm / numa_64.c

/*
 * Generic VM initialization for x86-64 NUMA setups.
 * Copyright 2002,2003 Andi Kleen, SuSE Labs.
 */
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/memblock.h>
#include <linux/mmzone.h>
#include <linux/ctype.h>
#include <linux/module.h>
#include <linux/nodemask.h>
#include <linux/sched.h>
#include <linux/acpi.h>

#include <asm/e820.h>
#include <asm/proto.h>
#include <asm/dma.h>
#include <asm/numa.h>
#include <asm/acpi.h>
#include <asm/amd_nb.h>

struct numa_memblk {
        u64                     start;
        u64                     end;
        int                     nid;
};

struct numa_meminfo {
        int                     nr_blks;
        struct numa_memblk      blk[NR_NODE_MEMBLKS];
};

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

nodemask_t cpu_nodes_parsed __initdata;
nodemask_t mem_nodes_parsed __initdata;

struct memnode memnode;

static unsigned long __initdata nodemap_addr;
static unsigned long __initdata nodemap_size;

static struct numa_meminfo numa_meminfo __initdata;

struct bootnode numa_nodes[MAX_NUMNODES] __initdata;

/*
 * Given a shift value, try to populate memnodemap[]
 * Returns :
 * 1 if OK
 * 0 if memnodmap[] too small (of shift too small)
 * -1 if node overlap or lost ram (shift too big)
 */
static int __init populate_memnodemap(const struct numa_meminfo *mi, int shift)
{
        unsigned long addr, end;
        int i, res = -1;

        memset(memnodemap, 0xff, sizeof(s16)*memnodemapsize);
        for (i = 0; i < mi->nr_blks; i++) {
                addr = mi->blk[i].start;
                end = mi->blk[i].end;
                if (addr >= end)
                        continue;
                if ((end >> shift) >= memnodemapsize)
                        return 0;
                do {
                        if (memnodemap[addr >> shift] != NUMA_NO_NODE)
                                return -1;
                        memnodemap[addr >> shift] = mi->blk[i].nid;
                        addr += (1UL << shift);
                } while (addr < end);
                res = 1;
        }
        return res;
}

static int __init allocate_cachealigned_memnodemap(void)
{
        unsigned long addr;

        memnodemap = memnode.embedded_map;
        if (memnodemapsize <= ARRAY_SIZE(memnode.embedded_map))
                return 0;

        addr = 0x8000;
        nodemap_size = roundup(sizeof(s16) * memnodemapsize, L1_CACHE_BYTES);
        nodemap_addr = memblock_find_in_range(addr, get_max_mapped(),
                                      nodemap_size, L1_CACHE_BYTES);
        if (nodemap_addr == MEMBLOCK_ERROR) {
                printk(KERN_ERR
                       "NUMA: Unable to allocate Memory to Node hash map\n");
                nodemap_addr = nodemap_size = 0;
                return -1;
        }
        memnodemap = phys_to_virt(nodemap_addr);
        memblock_x86_reserve_range(nodemap_addr, nodemap_addr + nodemap_size, "MEMNODEMAP");

        printk(KERN_DEBUG "NUMA: Allocated memnodemap from %lx - %lx\n",
               nodemap_addr, nodemap_addr + nodemap_size);
        return 0;
}

/*
 * The LSB of all start and end addresses in the node map is the value of the
 * maximum possible shift.
 */
static int __init extract_lsb_from_nodes(const struct numa_meminfo *mi)
{
        int i, nodes_used = 0;
        unsigned long start, end;
        unsigned long bitfield = 0, memtop = 0;

        for (i = 0; i < mi->nr_blks; i++) {
                start = mi->blk[i].start;
                end = mi->blk[i].end;
                if (start >= end)
                        continue;
                bitfield |= start;
                nodes_used++;
                if (end > memtop)
                        memtop = end;
        }
        if (nodes_used <= 1)
                i = 63;
        else
                i = find_first_bit(&bitfield, sizeof(unsigned long)*8);
        memnodemapsize = (memtop >> i)+1;
        return i;
}

static int __init compute_hash_shift(const struct numa_meminfo *mi)
{
        int shift;

        shift = extract_lsb_from_nodes(mi);
        if (allocate_cachealigned_memnodemap())
                return -1;
        printk(KERN_DEBUG "NUMA: Using %d for the hash shift.\n",
                shift);

        if (populate_memnodemap(mi, shift) != 1) {
                printk(KERN_INFO "Your memory is not aligned you need to "
                       "rebuild your kernel with a bigger NODEMAPSIZE "
                       "shift=%d\n", shift);
                return -1;
        }
        return shift;
}

int __meminit  __early_pfn_to_nid(unsigned long pfn)
{
        return phys_to_nid(pfn << PAGE_SHIFT);
}

static void * __init early_node_mem(int nodeid, unsigned long start,
                                    unsigned long end, unsigned long size,
                                    unsigned long align)
{
        unsigned long mem;

        /*
         * put it on high as possible
         * something will go with NODE_DATA
         */
        if (start < (MAX_DMA_PFN<<PAGE_SHIFT))
                start = MAX_DMA_PFN<<PAGE_SHIFT;
        if (start < (MAX_DMA32_PFN<<PAGE_SHIFT) &&
            end > (MAX_DMA32_PFN<<PAGE_SHIFT))
                start = MAX_DMA32_PFN<<PAGE_SHIFT;
        mem = memblock_x86_find_in_range_node(nodeid, start, end, size, align);
        if (mem != MEMBLOCK_ERROR)
                return __va(mem);

        /* extend the search scope */
        end = max_pfn_mapped << PAGE_SHIFT;
        start = MAX_DMA_PFN << PAGE_SHIFT;
        mem = memblock_find_in_range(start, end, size, align);
        if (mem != MEMBLOCK_ERROR)
                return __va(mem);

        printk(KERN_ERR "Cannot find %lu bytes in node %d\n",
                       size, nodeid);

        return NULL;
}

static __init int conflicting_memblks(unsigned long start, unsigned long end)
{
        struct numa_meminfo *mi = &numa_meminfo;
        int i;

        for (i = 0; i < mi->nr_blks; i++) {
                struct numa_memblk *blk = &mi->blk[i];

                if (blk->start == blk->end)
                        continue;
                if (blk->end > start && blk->start < end)
                        return blk->nid;
                if (blk->end == end && blk->start == start)
                        return blk->nid;
        }
        return -1;
}

int __init numa_add_memblk(int nid, u64 start, u64 end)
{
        struct numa_meminfo *mi = &numa_meminfo;
        int i;

        i = conflicting_memblks(start, end);
        if (i == nid) {
                printk(KERN_WARNING "NUMA: Warning: node %d (%Lx-%Lx) overlaps with itself (%Lx-%Lx)\n",
                       nid, start, end, numa_nodes[i].start, numa_nodes[i].end);
        } else if (i >= 0) {
                printk(KERN_ERR "NUMA: node %d (%Lx-%Lx) overlaps with node %d (%Lx-%Lx)\n",
                       nid, start, end, i,
                       numa_nodes[i].start, numa_nodes[i].end);
                return -EINVAL;
        }

        mi->blk[mi->nr_blks].start = start;
        mi->blk[mi->nr_blks].end = end;
        mi->blk[mi->nr_blks].nid = nid;
        mi->nr_blks++;
        return 0;
}

static __init void cutoff_node(int i, unsigned long start, unsigned long end)
{
        struct bootnode *nd = &numa_nodes[i];

        if (nd->start < start) {
                nd->start = start;
                if (nd->end < nd->start)
                        nd->start = nd->end;
        }
        if (nd->end > end) {
                nd->end = end;
                if (nd->start > nd->end)
                        nd->start = nd->end;
        }
}

/* Initialize bootmem allocator for a node */
void __init
setup_node_bootmem(int nodeid, unsigned long start, unsigned long end)
{
        unsigned long start_pfn, last_pfn, nodedata_phys;
        const int pgdat_size = roundup(sizeof(pg_data_t), PAGE_SIZE);
        int nid;

        if (!end)
                return;

        /*
         * Don't confuse VM with a node that doesn't have the
         * minimum amount of memory:
         */
        if (end && (end - start) < NODE_MIN_SIZE)
                return;

        start = roundup(start, ZONE_ALIGN);

        printk(KERN_INFO "Initmem setup node %d %016lx-%016lx\n", nodeid,
               start, end);

        start_pfn = start >> PAGE_SHIFT;
        last_pfn = end >> PAGE_SHIFT;

        node_data[nodeid] = early_node_mem(nodeid, start, end, pgdat_size,
                                           SMP_CACHE_BYTES);
        if (node_data[nodeid] == NULL)
                return;
        nodedata_phys = __pa(node_data[nodeid]);
        memblock_x86_reserve_range(nodedata_phys, nodedata_phys + pgdat_size, "NODE_DATA");
        printk(KERN_INFO "  NODE_DATA [%016lx - %016lx]\n", nodedata_phys,
                nodedata_phys + pgdat_size - 1);
        nid = phys_to_nid(nodedata_phys);
        if (nid != nodeid)
                printk(KERN_INFO "    NODE_DATA(%d) on node %d\n", nodeid, nid);

        memset(NODE_DATA(nodeid), 0, sizeof(pg_data_t));
        NODE_DATA(nodeid)->node_id = nodeid;
        NODE_DATA(nodeid)->node_start_pfn = start_pfn;
        NODE_DATA(nodeid)->node_spanned_pages = last_pfn - start_pfn;

        node_set_online(nodeid);
}

static int __init numa_cleanup_meminfo(struct numa_meminfo *mi)
{
        int i;

        /*
         * Join together blocks on the same node, holes between
         * which don't overlap with memory on other nodes.
         */
        for (i = 0; i < mi->nr_blks; ++i) {
                struct numa_memblk *bi = &mi->blk[i];
                int j, k;

                for (j = i + 1; j < mi->nr_blks; ++j) {
                        struct numa_memblk *bj = &mi->blk[j];
                        unsigned long start, end;

                        if (bi->nid != bj->nid)
                                continue;
                        start = min(bi->end, bj->end);
                        end = max(bi->start, bj->start);
                        for (k = 0; k < mi->nr_blks; ++k) {
                                struct numa_memblk *bk = &mi->blk[k];

                                if (bi->nid == bk->nid)
                                        continue;
                                if (start < bk->end && end > bk->start)
                                        break;
                        }
                        if (k < mi->nr_blks)
                                continue;
                        start = min(bi->start, bj->start);
                        end = max(bi->end, bj->end);
                        printk(KERN_INFO "NUMA: Node %d [%Lx,%Lx) + [%Lx,%Lx) -> [%lx,%lx)\n",
                               bi->nid, bi->start, bi->end, bj->start, bj->end,
                               start, end);
                        bi->start = start;
                        bi->end = end;
                        k = --mi->nr_blks - j;
                        memmove(mi->blk + j, mi->blk + j + 1,
                                k * sizeof(mi->blk[0]));
                        --j;
                }
        }

        return 0;
}

/*
 * Sanity check to catch more bad NUMA configurations (they are amazingly
 * common).  Make sure the nodes cover all memory.
 */
static int __init nodes_cover_memory(const struct bootnode *nodes)
{
        unsigned long numaram, e820ram;
        int i;

        numaram = 0;
        for_each_node_mask(i, mem_nodes_parsed) {
                unsigned long s = nodes[i].start >> PAGE_SHIFT;
                unsigned long e = nodes[i].end >> PAGE_SHIFT;
                numaram += e - s;
                numaram -= __absent_pages_in_range(i, s, e);
                if ((long)numaram < 0)
                        numaram = 0;
        }

        e820ram = max_pfn - (memblock_x86_hole_size(0,
                                        max_pfn << PAGE_SHIFT) >> PAGE_SHIFT);
        /* We seem to lose 3 pages somewhere. Allow 1M of slack. */
        if ((long)(e820ram - numaram) >= (1 << (20 - PAGE_SHIFT))) {
                printk(KERN_ERR "NUMA: nodes only cover %luMB of your %luMB e820 RAM. Not used.\n",
                       (numaram << PAGE_SHIFT) >> 20,
                       (e820ram << PAGE_SHIFT) >> 20);
                return 0;
        }
        return 1;
}

static int __init numa_register_memblks(struct numa_meminfo *mi)
{
        int i;

        /* Account for nodes with cpus and no memory */
        nodes_or(node_possible_map, mem_nodes_parsed, cpu_nodes_parsed);
        if (WARN_ON(nodes_empty(node_possible_map)))
                return -EINVAL;

        memnode_shift = compute_hash_shift(mi);
        if (memnode_shift < 0) {
                printk(KERN_ERR "NUMA: No NUMA node hash function found. Contact maintainer\n");
                return -EINVAL;
        }

        for (i = 0; i < mi->nr_blks; i++)
                memblock_x86_register_active_regions(mi->blk[i].nid,
                                        mi->blk[i].start >> PAGE_SHIFT,
                                        mi->blk[i].end >> PAGE_SHIFT);

        /* for out of order entries */
        sort_node_map();
        if (!nodes_cover_memory(numa_nodes))
                return -EINVAL;

        init_memory_mapping_high();

        /* Finally register nodes. */
        for_each_node_mask(i, node_possible_map)
                setup_node_bootmem(i, numa_nodes[i].start, numa_nodes[i].end);

        /*
         * Try again in case setup_node_bootmem missed one due to missing
         * bootmem.
         */
        for_each_node_mask(i, node_possible_map)
                if (!node_online(i))
                        setup_node_bootmem(i, numa_nodes[i].start,
                                           numa_nodes[i].end);

        return 0;
}

#ifdef CONFIG_NUMA_EMU
/* Numa emulation */
static struct bootnode nodes[MAX_NUMNODES] __initdata;
static struct bootnode physnodes[MAX_NUMNODES] __cpuinitdata;
static char *cmdline __initdata;

void __init numa_emu_cmdline(char *str)
{
        cmdline = str;
}

static int __init setup_physnodes(unsigned long start, unsigned long end)
{
        int ret = 0;
        int i;

        memset(physnodes, 0, sizeof(physnodes));

        for_each_node_mask(i, mem_nodes_parsed) {
                physnodes[i].start = numa_nodes[i].start;
                physnodes[i].end = numa_nodes[i].end;
        }

        /*
         * Basic sanity checking on the physical node map: there may be errors
         * if the SRAT or AMD code incorrectly reported the topology or the mem=
         * kernel parameter is used.
         */
        for (i = 0; i < MAX_NUMNODES; i++) {
                if (physnodes[i].start == physnodes[i].end)
                        continue;
                if (physnodes[i].start > end) {
                        physnodes[i].end = physnodes[i].start;
                        continue;
                }
                if (physnodes[i].end < start) {
                        physnodes[i].start = physnodes[i].end;
                        continue;
                }
                if (physnodes[i].start < start)
                        physnodes[i].start = start;
                if (physnodes[i].end > end)
                        physnodes[i].end = end;
                ret++;
        }

        /*
         * If no physical topology was detected, a single node is faked to cover
         * the entire address space.
         */
        if (!ret) {
                physnodes[ret].start = start;
                physnodes[ret].end = end;
                ret = 1;
        }
        return ret;
}

static void __init fake_physnodes(int acpi, int amd, int nr_nodes)
{
        int i;

        BUG_ON(acpi && amd);
#ifdef CONFIG_ACPI_NUMA
        if (acpi)
                acpi_fake_nodes(nodes, nr_nodes);
#endif
#ifdef CONFIG_AMD_NUMA
        if (amd)
                amd_fake_nodes(nodes, nr_nodes);
#endif
        if (!acpi && !amd)
                for (i = 0; i < nr_cpu_ids; i++)
                        numa_set_node(i, 0);
}

/*
 * Setups up nid to range from addr to addr + size.  If the end
 * boundary is greater than max_addr, then max_addr is used instead.
 * The return value is 0 if there is additional memory left for
 * allocation past addr and -1 otherwise.  addr is adjusted to be at
 * the end of the node.
 */
static int __init setup_node_range(int nid, u64 *addr, u64 size, u64 max_addr)
{
        int ret = 0;
        nodes[nid].start = *addr;
        *addr += size;
        if (*addr >= max_addr) {
                *addr = max_addr;
                ret = -1;
        }
        nodes[nid].end = *addr;
        node_set(nid, node_possible_map);
        printk(KERN_INFO "Faking node %d at %016Lx-%016Lx (%LuMB)\n", nid,
               nodes[nid].start, nodes[nid].end,
               (nodes[nid].end - nodes[nid].start) >> 20);
        return ret;
}

/*
 * Sets up nr_nodes fake nodes interleaved over physical nodes ranging from addr
 * to max_addr.  The return value is the number of nodes allocated.
 */
static int __init split_nodes_interleave(u64 addr, u64 max_addr, int nr_nodes)
{
        nodemask_t physnode_mask = NODE_MASK_NONE;
        u64 size;
        int big;
        int ret = 0;
        int i;

        if (nr_nodes <= 0)
                return -1;
        if (nr_nodes > MAX_NUMNODES) {
                pr_info("numa=fake=%d too large, reducing to %d\n",
                        nr_nodes, MAX_NUMNODES);
                nr_nodes = MAX_NUMNODES;
        }

        size = (max_addr - addr - memblock_x86_hole_size(addr, max_addr)) / nr_nodes;
        /*
         * Calculate the number of big nodes that can be allocated as a result
         * of consolidating the remainder.
         */
        big = ((size & ~FAKE_NODE_MIN_HASH_MASK) * nr_nodes) /
                FAKE_NODE_MIN_SIZE;

        size &= FAKE_NODE_MIN_HASH_MASK;
        if (!size) {
                pr_err("Not enough memory for each node.  "
                        "NUMA emulation disabled.\n");
                return -1;
        }

        for (i = 0; i < MAX_NUMNODES; i++)
                if (physnodes[i].start != physnodes[i].end)
                        node_set(i, physnode_mask);

        /*
         * Continue to fill physical nodes with fake nodes until there is no
         * memory left on any of them.
         */
        while (nodes_weight(physnode_mask)) {
                for_each_node_mask(i, physnode_mask) {
                        u64 end = physnodes[i].start + size;
                        u64 dma32_end = PFN_PHYS(MAX_DMA32_PFN);

                        if (ret < big)
                                end += FAKE_NODE_MIN_SIZE;

                        /*
                         * Continue to add memory to this fake node if its
                         * non-reserved memory is less than the per-node size.
                         */
                        while (end - physnodes[i].start -
                                memblock_x86_hole_size(physnodes[i].start, end) < size) {
                                end += FAKE_NODE_MIN_SIZE;
                                if (end > physnodes[i].end) {
                                        end = physnodes[i].end;
                                        break;
                                }
                        }

                        /*
                         * If there won't be at least FAKE_NODE_MIN_SIZE of
                         * non-reserved memory in ZONE_DMA32 for the next node,
                         * this one must extend to the boundary.
                         */
                        if (end < dma32_end && dma32_end - end -
                            memblock_x86_hole_size(end, dma32_end) < FAKE_NODE_MIN_SIZE)
                                end = dma32_end;

                        /*
                         * If there won't be enough non-reserved memory for the
                         * next node, this one must extend to the end of the
                         * physical node.
                         */
                        if (physnodes[i].end - end -
                            memblock_x86_hole_size(end, physnodes[i].end) < size)
                                end = physnodes[i].end;

                        /*
                         * Avoid allocating more nodes than requested, which can
                         * happen as a result of rounding down each node's size
                         * to FAKE_NODE_MIN_SIZE.
                         */
                        if (nodes_weight(physnode_mask) + ret >= nr_nodes)
                                end = physnodes[i].end;

                        if (setup_node_range(ret++, &physnodes[i].start,
                                                end - physnodes[i].start,
                                                physnodes[i].end) < 0)
                                node_clear(i, physnode_mask);
                }
        }
        return ret;
}

/*
 * Returns the end address of a node so that there is at least `size' amount of
 * non-reserved memory or `max_addr' is reached.
 */
static u64 __init find_end_of_node(u64 start, u64 max_addr, u64 size)
{
        u64 end = start + size;

        while (end - start - memblock_x86_hole_size(start, end) < size) {
                end += FAKE_NODE_MIN_SIZE;
                if (end > max_addr) {
                        end = max_addr;
                        break;
                }
        }
        return end;
}

/*
 * Sets up fake nodes of `size' interleaved over physical nodes ranging from
 * `addr' to `max_addr'.  The return value is the number of nodes allocated.
 */
static int __init split_nodes_size_interleave(u64 addr, u64 max_addr, u64 size)
{
        nodemask_t physnode_mask = NODE_MASK_NONE;
        u64 min_size;
        int ret = 0;
        int i;

        if (!size)
                return -1;
        /*
         * The limit on emulated nodes is MAX_NUMNODES, so the size per node is
         * increased accordingly if the requested size is too small.  This
         * creates a uniform distribution of node sizes across the entire
         * machine (but not necessarily over physical nodes).
         */
        min_size = (max_addr - addr - memblock_x86_hole_size(addr, max_addr)) /
                                                MAX_NUMNODES;
        min_size = max(min_size, FAKE_NODE_MIN_SIZE);
        if ((min_size & FAKE_NODE_MIN_HASH_MASK) < min_size)
                min_size = (min_size + FAKE_NODE_MIN_SIZE) &
                                                FAKE_NODE_MIN_HASH_MASK;
        if (size < min_size) {
                pr_err("Fake node size %LuMB too small, increasing to %LuMB\n",
                        size >> 20, min_size >> 20);
                size = min_size;
        }
        size &= FAKE_NODE_MIN_HASH_MASK;

        for (i = 0; i < MAX_NUMNODES; i++)
                if (physnodes[i].start != physnodes[i].end)
                        node_set(i, physnode_mask);
        /*
         * Fill physical nodes with fake nodes of size until there is no memory
         * left on any of them.
         */
        while (nodes_weight(physnode_mask)) {
                for_each_node_mask(i, physnode_mask) {
                        u64 dma32_end = MAX_DMA32_PFN << PAGE_SHIFT;
                        u64 end;

                        end = find_end_of_node(physnodes[i].start,
                                                physnodes[i].end, size);
                        /*
                         * If there won't be at least FAKE_NODE_MIN_SIZE of
                         * non-reserved memory in ZONE_DMA32 for the next node,
                         * this one must extend to the boundary.
                         */
                        if (end < dma32_end && dma32_end - end -
                            memblock_x86_hole_size(end, dma32_end) < FAKE_NODE_MIN_SIZE)
                                end = dma32_end;

                        /*
                         * If there won't be enough non-reserved memory for the
                         * next node, this one must extend to the end of the
                         * physical node.
                         */
                        if (physnodes[i].end - end -
                            memblock_x86_hole_size(end, physnodes[i].end) < size)
                                end = physnodes[i].end;

                        /*
                         * Setup the fake node that will be allocated as bootmem
                         * later.  If setup_node_range() returns non-zero, there
                         * is no more memory available on this physical node.
                         */
                        if (setup_node_range(ret++, &physnodes[i].start,
                                                end - physnodes[i].start,
                                                physnodes[i].end) < 0)
                                node_clear(i, physnode_mask);
                }
        }
        return ret;
}

/*
 * Sets up the system RAM area from start_pfn to last_pfn according to the
 * numa=fake command-line option.
 */
static int __init numa_emulation(unsigned long start_pfn,
                        unsigned long last_pfn, int acpi, int amd)
{
        static struct numa_meminfo ei __initdata;
        u64 addr = start_pfn << PAGE_SHIFT;
        u64 max_addr = last_pfn << PAGE_SHIFT;
        int num_nodes;
        int i;

        /*
         * If the numa=fake command-line contains a 'M' or 'G', it represents
         * the fixed node size.  Otherwise, if it is just a single number N,
         * split the system RAM into N fake nodes.
         */
        if (strchr(cmdline, 'M') || strchr(cmdline, 'G')) {
                u64 size;

                size = memparse(cmdline, &cmdline);
                num_nodes = split_nodes_size_interleave(addr, max_addr, size);
        } else {
                unsigned long n;

                n = simple_strtoul(cmdline, NULL, 0);
                num_nodes = split_nodes_interleave(addr, max_addr, n);
        }

        if (num_nodes < 0)
                return num_nodes;

        ei.nr_blks = num_nodes;
        for (i = 0; i < ei.nr_blks; i++) {
                ei.blk[i].start = nodes[i].start;
                ei.blk[i].end = nodes[i].end;
                ei.blk[i].nid = i;
        }

        memnode_shift = compute_hash_shift(&ei);
        if (memnode_shift < 0) {
                memnode_shift = 0;
                printk(KERN_ERR "No NUMA hash function found.  NUMA emulation "
                       "disabled.\n");
                return -1;
        }

        /*
         * We need to vacate all active ranges that may have been registered for
         * the e820 memory map.
         */
        remove_all_active_ranges();
        for_each_node_mask(i, node_possible_map)
                memblock_x86_register_active_regions(i, nodes[i].start >> PAGE_SHIFT,
                                                nodes[i].end >> PAGE_SHIFT);
        init_memory_mapping_high();
        for_each_node_mask(i, node_possible_map)
                setup_node_bootmem(i, nodes[i].start, nodes[i].end);
        setup_physnodes(addr, max_addr);
        fake_physnodes(acpi, amd, num_nodes);
        numa_init_array();
        return 0;
}
#endif /* CONFIG_NUMA_EMU */

static int dummy_numa_init(void)
{
        printk(KERN_INFO "%s\n",
               numa_off ? "NUMA turned off" : "No NUMA configuration found");
        printk(KERN_INFO "Faking a node at %016lx-%016lx\n",
               0LU, max_pfn << PAGE_SHIFT);

        node_set(0, cpu_nodes_parsed);
        node_set(0, mem_nodes_parsed);
        numa_add_memblk(0, 0, (u64)max_pfn << PAGE_SHIFT);
        numa_nodes[0].start = 0;
        numa_nodes[0].end = (u64)max_pfn << PAGE_SHIFT;

        return 0;
}

void __init initmem_init(void)
{
        int (*numa_init[])(void) = { [2] = dummy_numa_init };
        int i, j;

        if (!numa_off) {
#ifdef CONFIG_ACPI_NUMA
                numa_init[0] = x86_acpi_numa_init;
#endif
#ifdef CONFIG_AMD_NUMA
                numa_init[1] = amd_numa_init;
#endif
        }

        for (i = 0; i < ARRAY_SIZE(numa_init); i++) {
                if (!numa_init[i])
                        continue;

                for (j = 0; j < MAX_LOCAL_APIC; j++)
                        set_apicid_to_node(j, NUMA_NO_NODE);

                nodes_clear(cpu_nodes_parsed);
                nodes_clear(mem_nodes_parsed);
                nodes_clear(node_possible_map);
                nodes_clear(node_online_map);
                memset(&numa_meminfo, 0, sizeof(numa_meminfo));
                memset(numa_nodes, 0, sizeof(numa_nodes));
                remove_all_active_ranges();

                if (numa_init[i]() < 0)
                        continue;

                /* clean up the node list */
                for (j = 0; j < MAX_NUMNODES; j++)
                        cutoff_node(j, 0, max_pfn << PAGE_SHIFT);

#ifdef CONFIG_NUMA_EMU
                setup_physnodes(0, max_pfn << PAGE_SHIFT);
                if (cmdline && !numa_emulation(0, max_pfn, i == 0, i == 1))
                        return;
                setup_physnodes(0, max_pfn << PAGE_SHIFT);
                nodes_clear(node_possible_map);
                nodes_clear(node_online_map);
#endif
                if (numa_cleanup_meminfo(&numa_meminfo) < 0)
                        continue;

                if (numa_register_memblks(&numa_meminfo) < 0)
                        continue;

                for (j = 0; j < nr_cpu_ids; j++) {
                        int nid = early_cpu_to_node(j);

                        if (nid == NUMA_NO_NODE)
                                continue;
                        if (!node_online(nid))
                                numa_clear_node(j);
                }
                numa_init_array();
                return;
        }
        BUG();
}

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_all_memory_core_early(MAX_NUMNODES);

        return pages;
}

int __cpuinit numa_cpu_node(int cpu)
{
        int apicid = early_per_cpu(x86_cpu_to_apicid, cpu);

        if (apicid != BAD_APICID)
                return __apicid_to_node[apicid];
        return NUMA_NO_NODE;
}

/*
 * UGLINESS AHEAD: Currently, CONFIG_NUMA_EMU is 64bit only and makes use
 * of 64bit specific data structures.  The distinction is artificial and
 * should be removed.  numa_{add|remove}_cpu() are implemented in numa.c
 * for both 32 and 64bit when CONFIG_NUMA_EMU is disabled but here when
 * enabled.
 *
 * NUMA emulation is planned to be made generic and the following and other
 * related code should be moved to numa.c.
 */
#ifdef CONFIG_NUMA_EMU
# ifndef CONFIG_DEBUG_PER_CPU_MAPS
void __cpuinit numa_add_cpu(int cpu)
{
        unsigned long addr;
        int physnid, nid;

        nid = numa_cpu_node(cpu);
        if (nid == NUMA_NO_NODE)
                nid = early_cpu_to_node(cpu);
        BUG_ON(nid == NUMA_NO_NODE || !node_online(nid));

        /*
         * Use the starting address of the emulated node to find which physical
         * node it is allocated on.
         */
        addr = node_start_pfn(nid) << PAGE_SHIFT;
        for (physnid = 0; physnid < MAX_NUMNODES; physnid++)
                if (addr >= physnodes[physnid].start &&
                    addr < physnodes[physnid].end)
                        break;

        /*
         * Map the cpu to each emulated node that is allocated on the physical
         * node of the cpu's apic id.
         */
        for_each_online_node(nid) {
                addr = node_start_pfn(nid) << PAGE_SHIFT;
                if (addr >= physnodes[physnid].start &&
                    addr < physnodes[physnid].end)
                        cpumask_set_cpu(cpu, node_to_cpumask_map[nid]);
        }
}

void __cpuinit numa_remove_cpu(int cpu)
{
        int i;

        for_each_online_node(i)
                cpumask_clear_cpu(cpu, node_to_cpumask_map[i]);
}
# else  /* !CONFIG_DEBUG_PER_CPU_MAPS */
static void __cpuinit numa_set_cpumask(int cpu, int enable)
{
        int node = early_cpu_to_node(cpu);
        struct cpumask *mask;
        int i;

        if (node == NUMA_NO_NODE) {
                /* early_cpu_to_node() already emits a warning and trace */
                return;
        }
        for_each_online_node(i) {
                unsigned long addr;

                addr = node_start_pfn(i) << PAGE_SHIFT;
                if (addr < physnodes[node].start ||
                                        addr >= physnodes[node].end)
                        continue;
                mask = debug_cpumask_set_cpu(cpu, enable);
                if (!mask)
                        return;

                if (enable)
                        cpumask_set_cpu(cpu, mask);
                else
                        cpumask_clear_cpu(cpu, mask);
        }
}

void __cpuinit numa_add_cpu(int cpu)
{
        numa_set_cpumask(cpu, 1);
}

void __cpuinit numa_remove_cpu(int cpu)
{
        numa_set_cpumask(cpu, 0);
}
# endif /* !CONFIG_DEBUG_PER_CPU_MAPS */
#endif  /* CONFIG_NUMA_EMU */