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-rw-r--r--mm/sparse.c793
1 files changed, 793 insertions, 0 deletions
diff --git a/mm/sparse.c b/mm/sparse.c
new file mode 100644
index 00000000..a8bc7d36
--- /dev/null
+++ b/mm/sparse.c
@@ -0,0 +1,793 @@
+/*
+ * sparse memory mappings.
+ */
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/mmzone.h>
+#include <linux/bootmem.h>
+#include <linux/highmem.h>
+#include <linux/export.h>
+#include <linux/spinlock.h>
+#include <linux/vmalloc.h>
+#include "internal.h"
+#include <asm/dma.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+
+/*
+ * Permanent SPARSEMEM data:
+ *
+ * 1) mem_section - memory sections, mem_map's for valid memory
+ */
+#ifdef CONFIG_SPARSEMEM_EXTREME
+struct mem_section *mem_section[NR_SECTION_ROOTS]
+ ____cacheline_internodealigned_in_smp;
+#else
+struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT]
+ ____cacheline_internodealigned_in_smp;
+#endif
+EXPORT_SYMBOL(mem_section);
+
+#ifdef NODE_NOT_IN_PAGE_FLAGS
+/*
+ * If we did not store the node number in the page then we have to
+ * do a lookup in the section_to_node_table in order to find which
+ * node the page belongs to.
+ */
+#if MAX_NUMNODES <= 256
+static u8 section_to_node_table[NR_MEM_SECTIONS] __cacheline_aligned;
+#else
+static u16 section_to_node_table[NR_MEM_SECTIONS] __cacheline_aligned;
+#endif
+
+int page_to_nid(const struct page *page)
+{
+ return section_to_node_table[page_to_section(page)];
+}
+EXPORT_SYMBOL(page_to_nid);
+
+static void set_section_nid(unsigned long section_nr, int nid)
+{
+ section_to_node_table[section_nr] = nid;
+}
+#else /* !NODE_NOT_IN_PAGE_FLAGS */
+static inline void set_section_nid(unsigned long section_nr, int nid)
+{
+}
+#endif
+
+#ifdef CONFIG_SPARSEMEM_EXTREME
+static struct mem_section noinline __init_refok *sparse_index_alloc(int nid)
+{
+ struct mem_section *section = NULL;
+ unsigned long array_size = SECTIONS_PER_ROOT *
+ sizeof(struct mem_section);
+
+ if (slab_is_available()) {
+ if (node_state(nid, N_HIGH_MEMORY))
+ section = kmalloc_node(array_size, GFP_KERNEL, nid);
+ else
+ section = kmalloc(array_size, GFP_KERNEL);
+ } else
+ section = alloc_bootmem_node(NODE_DATA(nid), array_size);
+
+ if (section)
+ memset(section, 0, array_size);
+
+ return section;
+}
+
+static int __meminit sparse_index_init(unsigned long section_nr, int nid)
+{
+ static DEFINE_SPINLOCK(index_init_lock);
+ unsigned long root = SECTION_NR_TO_ROOT(section_nr);
+ struct mem_section *section;
+ int ret = 0;
+
+ if (mem_section[root])
+ return -EEXIST;
+
+ section = sparse_index_alloc(nid);
+ if (!section)
+ return -ENOMEM;
+ /*
+ * This lock keeps two different sections from
+ * reallocating for the same index
+ */
+ spin_lock(&index_init_lock);
+
+ if (mem_section[root]) {
+ ret = -EEXIST;
+ goto out;
+ }
+
+ mem_section[root] = section;
+out:
+ spin_unlock(&index_init_lock);
+ return ret;
+}
+#else /* !SPARSEMEM_EXTREME */
+static inline int sparse_index_init(unsigned long section_nr, int nid)
+{
+ return 0;
+}
+#endif
+
+/*
+ * Although written for the SPARSEMEM_EXTREME case, this happens
+ * to also work for the flat array case because
+ * NR_SECTION_ROOTS==NR_MEM_SECTIONS.
+ */
+int __section_nr(struct mem_section* ms)
+{
+ unsigned long root_nr;
+ struct mem_section* root;
+
+ for (root_nr = 0; root_nr < NR_SECTION_ROOTS; root_nr++) {
+ root = __nr_to_section(root_nr * SECTIONS_PER_ROOT);
+ if (!root)
+ continue;
+
+ if ((ms >= root) && (ms < (root + SECTIONS_PER_ROOT)))
+ break;
+ }
+
+ return (root_nr * SECTIONS_PER_ROOT) + (ms - root);
+}
+
+/*
+ * During early boot, before section_mem_map is used for an actual
+ * mem_map, we use section_mem_map to store the section's NUMA
+ * node. This keeps us from having to use another data structure. The
+ * node information is cleared just before we store the real mem_map.
+ */
+static inline unsigned long sparse_encode_early_nid(int nid)
+{
+ return (nid << SECTION_NID_SHIFT);
+}
+
+static inline int sparse_early_nid(struct mem_section *section)
+{
+ return (section->section_mem_map >> SECTION_NID_SHIFT);
+}
+
+/* Validate the physical addressing limitations of the model */
+void __meminit mminit_validate_memmodel_limits(unsigned long *start_pfn,
+ unsigned long *end_pfn)
+{
+ unsigned long max_sparsemem_pfn = 1UL << (MAX_PHYSMEM_BITS-PAGE_SHIFT);
+
+ /*
+ * Sanity checks - do not allow an architecture to pass
+ * in larger pfns than the maximum scope of sparsemem:
+ */
+ if (*start_pfn > max_sparsemem_pfn) {
+ mminit_dprintk(MMINIT_WARNING, "pfnvalidation",
+ "Start of range %lu -> %lu exceeds SPARSEMEM max %lu\n",
+ *start_pfn, *end_pfn, max_sparsemem_pfn);
+ WARN_ON_ONCE(1);
+ *start_pfn = max_sparsemem_pfn;
+ *end_pfn = max_sparsemem_pfn;
+ } else if (*end_pfn > max_sparsemem_pfn) {
+ mminit_dprintk(MMINIT_WARNING, "pfnvalidation",
+ "End of range %lu -> %lu exceeds SPARSEMEM max %lu\n",
+ *start_pfn, *end_pfn, max_sparsemem_pfn);
+ WARN_ON_ONCE(1);
+ *end_pfn = max_sparsemem_pfn;
+ }
+}
+
+/* Record a memory area against a node. */
+void __init memory_present(int nid, unsigned long start, unsigned long end)
+{
+ unsigned long pfn;
+
+ start &= PAGE_SECTION_MASK;
+ mminit_validate_memmodel_limits(&start, &end);
+ for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION) {
+ unsigned long section = pfn_to_section_nr(pfn);
+ struct mem_section *ms;
+
+ sparse_index_init(section, nid);
+ set_section_nid(section, nid);
+
+ ms = __nr_to_section(section);
+ if (!ms->section_mem_map)
+ ms->section_mem_map = sparse_encode_early_nid(nid) |
+ SECTION_MARKED_PRESENT;
+ }
+}
+
+/*
+ * Only used by the i386 NUMA architecures, but relatively
+ * generic code.
+ */
+unsigned long __init node_memmap_size_bytes(int nid, unsigned long start_pfn,
+ unsigned long end_pfn)
+{
+ unsigned long pfn;
+ unsigned long nr_pages = 0;
+
+ mminit_validate_memmodel_limits(&start_pfn, &end_pfn);
+ for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
+ if (nid != early_pfn_to_nid(pfn))
+ continue;
+
+ if (pfn_present(pfn))
+ nr_pages += PAGES_PER_SECTION;
+ }
+
+ return nr_pages * sizeof(struct page);
+}
+
+/*
+ * Subtle, we encode the real pfn into the mem_map such that
+ * the identity pfn - section_mem_map will return the actual
+ * physical page frame number.
+ */
+static unsigned long sparse_encode_mem_map(struct page *mem_map, unsigned long pnum)
+{
+ return (unsigned long)(mem_map - (section_nr_to_pfn(pnum)));
+}
+
+/*
+ * Decode mem_map from the coded memmap
+ */
+struct page *sparse_decode_mem_map(unsigned long coded_mem_map, unsigned long pnum)
+{
+ /* mask off the extra low bits of information */
+ coded_mem_map &= SECTION_MAP_MASK;
+ return ((struct page *)coded_mem_map) + section_nr_to_pfn(pnum);
+}
+
+static int __meminit sparse_init_one_section(struct mem_section *ms,
+ unsigned long pnum, struct page *mem_map,
+ unsigned long *pageblock_bitmap)
+{
+ if (!present_section(ms))
+ return -EINVAL;
+
+ ms->section_mem_map &= ~SECTION_MAP_MASK;
+ ms->section_mem_map |= sparse_encode_mem_map(mem_map, pnum) |
+ SECTION_HAS_MEM_MAP;
+ ms->pageblock_flags = pageblock_bitmap;
+
+ return 1;
+}
+
+unsigned long usemap_size(void)
+{
+ unsigned long size_bytes;
+ size_bytes = roundup(SECTION_BLOCKFLAGS_BITS, 8) / 8;
+ size_bytes = roundup(size_bytes, sizeof(unsigned long));
+ return size_bytes;
+}
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+static unsigned long *__kmalloc_section_usemap(void)
+{
+ return kmalloc(usemap_size(), GFP_KERNEL);
+}
+#endif /* CONFIG_MEMORY_HOTPLUG */
+
+#ifdef CONFIG_MEMORY_HOTREMOVE
+static unsigned long * __init
+sparse_early_usemaps_alloc_pgdat_section(struct pglist_data *pgdat,
+ unsigned long count)
+{
+ unsigned long section_nr;
+
+ /*
+ * A page may contain usemaps for other sections preventing the
+ * page being freed and making a section unremovable while
+ * other sections referencing the usemap retmain active. Similarly,
+ * a pgdat can prevent a section being removed. If section A
+ * contains a pgdat and section B contains the usemap, both
+ * sections become inter-dependent. This allocates usemaps
+ * from the same section as the pgdat where possible to avoid
+ * this problem.
+ */
+ section_nr = pfn_to_section_nr(__pa(pgdat) >> PAGE_SHIFT);
+ return alloc_bootmem_section(usemap_size() * count, section_nr);
+}
+
+static void __init check_usemap_section_nr(int nid, unsigned long *usemap)
+{
+ unsigned long usemap_snr, pgdat_snr;
+ static unsigned long old_usemap_snr = NR_MEM_SECTIONS;
+ static unsigned long old_pgdat_snr = NR_MEM_SECTIONS;
+ struct pglist_data *pgdat = NODE_DATA(nid);
+ int usemap_nid;
+
+ usemap_snr = pfn_to_section_nr(__pa(usemap) >> PAGE_SHIFT);
+ pgdat_snr = pfn_to_section_nr(__pa(pgdat) >> PAGE_SHIFT);
+ if (usemap_snr == pgdat_snr)
+ return;
+
+ if (old_usemap_snr == usemap_snr && old_pgdat_snr == pgdat_snr)
+ /* skip redundant message */
+ return;
+
+ old_usemap_snr = usemap_snr;
+ old_pgdat_snr = pgdat_snr;
+
+ usemap_nid = sparse_early_nid(__nr_to_section(usemap_snr));
+ if (usemap_nid != nid) {
+ printk(KERN_INFO
+ "node %d must be removed before remove section %ld\n",
+ nid, usemap_snr);
+ return;
+ }
+ /*
+ * There is a circular dependency.
+ * Some platforms allow un-removable section because they will just
+ * gather other removable sections for dynamic partitioning.
+ * Just notify un-removable section's number here.
+ */
+ printk(KERN_INFO "Section %ld and %ld (node %d)", usemap_snr,
+ pgdat_snr, nid);
+ printk(KERN_CONT
+ " have a circular dependency on usemap and pgdat allocations\n");
+}
+#else
+static unsigned long * __init
+sparse_early_usemaps_alloc_pgdat_section(struct pglist_data *pgdat,
+ unsigned long count)
+{
+ return NULL;
+}
+
+static void __init check_usemap_section_nr(int nid, unsigned long *usemap)
+{
+}
+#endif /* CONFIG_MEMORY_HOTREMOVE */
+
+static void __init sparse_early_usemaps_alloc_node(unsigned long**usemap_map,
+ unsigned long pnum_begin,
+ unsigned long pnum_end,
+ unsigned long usemap_count, int nodeid)
+{
+ void *usemap;
+ unsigned long pnum;
+ int size = usemap_size();
+
+ usemap = sparse_early_usemaps_alloc_pgdat_section(NODE_DATA(nodeid),
+ usemap_count);
+ if (!usemap) {
+ usemap = alloc_bootmem_node(NODE_DATA(nodeid), size * usemap_count);
+ if (!usemap) {
+ printk(KERN_WARNING "%s: allocation failed\n", __func__);
+ return;
+ }
+ }
+
+ for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
+ if (!present_section_nr(pnum))
+ continue;
+ usemap_map[pnum] = usemap;
+ usemap += size;
+ check_usemap_section_nr(nodeid, usemap_map[pnum]);
+ }
+}
+
+#ifndef CONFIG_SPARSEMEM_VMEMMAP
+struct page __init *sparse_mem_map_populate(unsigned long pnum, int nid)
+{
+ struct page *map;
+ unsigned long size;
+
+ map = alloc_remap(nid, sizeof(struct page) * PAGES_PER_SECTION);
+ if (map)
+ return map;
+
+ size = PAGE_ALIGN(sizeof(struct page) * PAGES_PER_SECTION);
+ map = __alloc_bootmem_node_high(NODE_DATA(nid), size,
+ PAGE_SIZE, __pa(MAX_DMA_ADDRESS));
+ return map;
+}
+void __init sparse_mem_maps_populate_node(struct page **map_map,
+ unsigned long pnum_begin,
+ unsigned long pnum_end,
+ unsigned long map_count, int nodeid)
+{
+ void *map;
+ unsigned long pnum;
+ unsigned long size = sizeof(struct page) * PAGES_PER_SECTION;
+
+ map = alloc_remap(nodeid, size * map_count);
+ if (map) {
+ for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
+ if (!present_section_nr(pnum))
+ continue;
+ map_map[pnum] = map;
+ map += size;
+ }
+ return;
+ }
+
+ size = PAGE_ALIGN(size);
+ map = __alloc_bootmem_node_high(NODE_DATA(nodeid), size * map_count,
+ PAGE_SIZE, __pa(MAX_DMA_ADDRESS));
+ if (map) {
+ for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
+ if (!present_section_nr(pnum))
+ continue;
+ map_map[pnum] = map;
+ map += size;
+ }
+ return;
+ }
+
+ /* fallback */
+ for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
+ struct mem_section *ms;
+
+ if (!present_section_nr(pnum))
+ continue;
+ map_map[pnum] = sparse_mem_map_populate(pnum, nodeid);
+ if (map_map[pnum])
+ continue;
+ ms = __nr_to_section(pnum);
+ printk(KERN_ERR "%s: sparsemem memory map backing failed "
+ "some memory will not be available.\n", __func__);
+ ms->section_mem_map = 0;
+ }
+}
+#endif /* !CONFIG_SPARSEMEM_VMEMMAP */
+
+#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
+static void __init sparse_early_mem_maps_alloc_node(struct page **map_map,
+ unsigned long pnum_begin,
+ unsigned long pnum_end,
+ unsigned long map_count, int nodeid)
+{
+ sparse_mem_maps_populate_node(map_map, pnum_begin, pnum_end,
+ map_count, nodeid);
+}
+#else
+static struct page __init *sparse_early_mem_map_alloc(unsigned long pnum)
+{
+ struct page *map;
+ struct mem_section *ms = __nr_to_section(pnum);
+ int nid = sparse_early_nid(ms);
+
+ map = sparse_mem_map_populate(pnum, nid);
+ if (map)
+ return map;
+
+ printk(KERN_ERR "%s: sparsemem memory map backing failed "
+ "some memory will not be available.\n", __func__);
+ ms->section_mem_map = 0;
+ return NULL;
+}
+#endif
+
+void __attribute__((weak)) __meminit vmemmap_populate_print_last(void)
+{
+}
+
+/*
+ * Allocate the accumulated non-linear sections, allocate a mem_map
+ * for each and record the physical to section mapping.
+ */
+void __init sparse_init(void)
+{
+ unsigned long pnum;
+ struct page *map;
+ unsigned long *usemap;
+ unsigned long **usemap_map;
+ int size;
+ int nodeid_begin = 0;
+ unsigned long pnum_begin = 0;
+ unsigned long usemap_count;
+#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
+ unsigned long map_count;
+ int size2;
+ struct page **map_map;
+#endif
+
+ /*
+ * map is using big page (aka 2M in x86 64 bit)
+ * usemap is less one page (aka 24 bytes)
+ * so alloc 2M (with 2M align) and 24 bytes in turn will
+ * make next 2M slip to one more 2M later.
+ * then in big system, the memory will have a lot of holes...
+ * here try to allocate 2M pages continuously.
+ *
+ * powerpc need to call sparse_init_one_section right after each
+ * sparse_early_mem_map_alloc, so allocate usemap_map at first.
+ */
+ size = sizeof(unsigned long *) * NR_MEM_SECTIONS;
+ usemap_map = alloc_bootmem(size);
+ if (!usemap_map)
+ panic("can not allocate usemap_map\n");
+
+ for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) {
+ struct mem_section *ms;
+
+ if (!present_section_nr(pnum))
+ continue;
+ ms = __nr_to_section(pnum);
+ nodeid_begin = sparse_early_nid(ms);
+ pnum_begin = pnum;
+ break;
+ }
+ usemap_count = 1;
+ for (pnum = pnum_begin + 1; pnum < NR_MEM_SECTIONS; pnum++) {
+ struct mem_section *ms;
+ int nodeid;
+
+ if (!present_section_nr(pnum))
+ continue;
+ ms = __nr_to_section(pnum);
+ nodeid = sparse_early_nid(ms);
+ if (nodeid == nodeid_begin) {
+ usemap_count++;
+ continue;
+ }
+ /* ok, we need to take cake of from pnum_begin to pnum - 1*/
+ sparse_early_usemaps_alloc_node(usemap_map, pnum_begin, pnum,
+ usemap_count, nodeid_begin);
+ /* new start, update count etc*/
+ nodeid_begin = nodeid;
+ pnum_begin = pnum;
+ usemap_count = 1;
+ }
+ /* ok, last chunk */
+ sparse_early_usemaps_alloc_node(usemap_map, pnum_begin, NR_MEM_SECTIONS,
+ usemap_count, nodeid_begin);
+
+#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
+ size2 = sizeof(struct page *) * NR_MEM_SECTIONS;
+ map_map = alloc_bootmem(size2);
+ if (!map_map)
+ panic("can not allocate map_map\n");
+
+ for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) {
+ struct mem_section *ms;
+
+ if (!present_section_nr(pnum))
+ continue;
+ ms = __nr_to_section(pnum);
+ nodeid_begin = sparse_early_nid(ms);
+ pnum_begin = pnum;
+ break;
+ }
+ map_count = 1;
+ for (pnum = pnum_begin + 1; pnum < NR_MEM_SECTIONS; pnum++) {
+ struct mem_section *ms;
+ int nodeid;
+
+ if (!present_section_nr(pnum))
+ continue;
+ ms = __nr_to_section(pnum);
+ nodeid = sparse_early_nid(ms);
+ if (nodeid == nodeid_begin) {
+ map_count++;
+ continue;
+ }
+ /* ok, we need to take cake of from pnum_begin to pnum - 1*/
+ sparse_early_mem_maps_alloc_node(map_map, pnum_begin, pnum,
+ map_count, nodeid_begin);
+ /* new start, update count etc*/
+ nodeid_begin = nodeid;
+ pnum_begin = pnum;
+ map_count = 1;
+ }
+ /* ok, last chunk */
+ sparse_early_mem_maps_alloc_node(map_map, pnum_begin, NR_MEM_SECTIONS,
+ map_count, nodeid_begin);
+#endif
+
+ for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) {
+ if (!present_section_nr(pnum))
+ continue;
+
+ usemap = usemap_map[pnum];
+ if (!usemap)
+ continue;
+
+#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
+ map = map_map[pnum];
+#else
+ map = sparse_early_mem_map_alloc(pnum);
+#endif
+ if (!map)
+ continue;
+
+ sparse_init_one_section(__nr_to_section(pnum), pnum, map,
+ usemap);
+ }
+
+ vmemmap_populate_print_last();
+
+#ifdef CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER
+ free_bootmem(__pa(map_map), size2);
+#endif
+ free_bootmem(__pa(usemap_map), size);
+}
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid,
+ unsigned long nr_pages)
+{
+ /* This will make the necessary allocations eventually. */
+ return sparse_mem_map_populate(pnum, nid);
+}
+static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages)
+{
+ return; /* XXX: Not implemented yet */
+}
+static void free_map_bootmem(struct page *page, unsigned long nr_pages)
+{
+}
+#else
+static struct page *__kmalloc_section_memmap(unsigned long nr_pages)
+{
+ struct page *page, *ret;
+ unsigned long memmap_size = sizeof(struct page) * nr_pages;
+
+ page = alloc_pages(GFP_KERNEL|__GFP_NOWARN, get_order(memmap_size));
+ if (page)
+ goto got_map_page;
+
+ ret = vmalloc(memmap_size);
+ if (ret)
+ goto got_map_ptr;
+
+ return NULL;
+got_map_page:
+ ret = (struct page *)pfn_to_kaddr(page_to_pfn(page));
+got_map_ptr:
+ memset(ret, 0, memmap_size);
+
+ return ret;
+}
+
+static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid,
+ unsigned long nr_pages)
+{
+ return __kmalloc_section_memmap(nr_pages);
+}
+
+static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages)
+{
+ if (is_vmalloc_addr(memmap))
+ vfree(memmap);
+ else
+ free_pages((unsigned long)memmap,
+ get_order(sizeof(struct page) * nr_pages));
+}
+
+static void free_map_bootmem(struct page *page, unsigned long nr_pages)
+{
+ unsigned long maps_section_nr, removing_section_nr, i;
+ unsigned long magic;
+
+ for (i = 0; i < nr_pages; i++, page++) {
+ magic = (unsigned long) page->lru.next;
+
+ BUG_ON(magic == NODE_INFO);
+
+ maps_section_nr = pfn_to_section_nr(page_to_pfn(page));
+ removing_section_nr = page->private;
+
+ /*
+ * When this function is called, the removing section is
+ * logical offlined state. This means all pages are isolated
+ * from page allocator. If removing section's memmap is placed
+ * on the same section, it must not be freed.
+ * If it is freed, page allocator may allocate it which will
+ * be removed physically soon.
+ */
+ if (maps_section_nr != removing_section_nr)
+ put_page_bootmem(page);
+ }
+}
+#endif /* CONFIG_SPARSEMEM_VMEMMAP */
+
+static void free_section_usemap(struct page *memmap, unsigned long *usemap)
+{
+ struct page *usemap_page;
+ unsigned long nr_pages;
+
+ if (!usemap)
+ return;
+
+ usemap_page = virt_to_page(usemap);
+ /*
+ * Check to see if allocation came from hot-plug-add
+ */
+ if (PageSlab(usemap_page)) {
+ kfree(usemap);
+ if (memmap)
+ __kfree_section_memmap(memmap, PAGES_PER_SECTION);
+ return;
+ }
+
+ /*
+ * The usemap came from bootmem. This is packed with other usemaps
+ * on the section which has pgdat at boot time. Just keep it as is now.
+ */
+
+ if (memmap) {
+ struct page *memmap_page;
+ memmap_page = virt_to_page(memmap);
+
+ nr_pages = PAGE_ALIGN(PAGES_PER_SECTION * sizeof(struct page))
+ >> PAGE_SHIFT;
+
+ free_map_bootmem(memmap_page, nr_pages);
+ }
+}
+
+/*
+ * returns the number of sections whose mem_maps were properly
+ * set. If this is <=0, then that means that the passed-in
+ * map was not consumed and must be freed.
+ */
+int __meminit sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
+ int nr_pages)
+{
+ unsigned long section_nr = pfn_to_section_nr(start_pfn);
+ struct pglist_data *pgdat = zone->zone_pgdat;
+ struct mem_section *ms;
+ struct page *memmap;
+ unsigned long *usemap;
+ unsigned long flags;
+ int ret;
+
+ /*
+ * no locking for this, because it does its own
+ * plus, it does a kmalloc
+ */
+ ret = sparse_index_init(section_nr, pgdat->node_id);
+ if (ret < 0 && ret != -EEXIST)
+ return ret;
+ memmap = kmalloc_section_memmap(section_nr, pgdat->node_id, nr_pages);
+ if (!memmap)
+ return -ENOMEM;
+ usemap = __kmalloc_section_usemap();
+ if (!usemap) {
+ __kfree_section_memmap(memmap, nr_pages);
+ return -ENOMEM;
+ }
+
+ pgdat_resize_lock(pgdat, &flags);
+
+ ms = __pfn_to_section(start_pfn);
+ if (ms->section_mem_map & SECTION_MARKED_PRESENT) {
+ ret = -EEXIST;
+ goto out;
+ }
+
+ ms->section_mem_map |= SECTION_MARKED_PRESENT;
+
+ ret = sparse_init_one_section(ms, section_nr, memmap, usemap);
+
+out:
+ pgdat_resize_unlock(pgdat, &flags);
+ if (ret <= 0) {
+ kfree(usemap);
+ __kfree_section_memmap(memmap, nr_pages);
+ }
+ return ret;
+}
+
+void sparse_remove_one_section(struct zone *zone, struct mem_section *ms)
+{
+ struct page *memmap = NULL;
+ unsigned long *usemap = NULL;
+
+ if (ms->section_mem_map) {
+ usemap = ms->pageblock_flags;
+ memmap = sparse_decode_mem_map(ms->section_mem_map,
+ __section_nr(ms));
+ ms->section_mem_map = 0;
+ ms->pageblock_flags = NULL;
+ }
+
+ free_section_usemap(memmap, usemap);
+}
+#endif
generated by cgit (git 2.34.1) at 2024-12-20 07:46:41 +0000