[patch 2/3] vfs: dcache cleanups
[safe/jmp/linux-2.6] / mm / sparse.c
index 52843a7..36511c7 100644 (file)
@@ -8,6 +8,7 @@
 #include <linux/module.h>
 #include <linux/spinlock.h>
 #include <linux/vmalloc.h>
+#include "internal.h"
 #include <asm/dma.h>
 #include <asm/pgalloc.h>
 #include <asm/pgtable.h>
@@ -83,6 +84,8 @@ static int __meminit sparse_index_init(unsigned long section_nr, int nid)
                return -EEXIST;
 
        section = sparse_index_alloc(nid);
+       if (!section)
+               return -ENOMEM;
        /*
         * This lock keeps two different sections from
         * reallocating for the same index
@@ -147,8 +150,18 @@ static inline int sparse_early_nid(struct mem_section *section)
 /* Record a memory area against a node. */
 void __init memory_present(int nid, unsigned long start, unsigned long end)
 {
+       unsigned long max_arch_pfn = 1UL << (MAX_PHYSMEM_BITS-PAGE_SHIFT);
        unsigned long pfn;
 
+       /*
+        * Sanity checks - do not allow an architecture to pass
+        * in larger pfns than the maximum scope of sparsemem:
+        */
+       if (start >= max_arch_pfn)
+               return;
+       if (end >= max_arch_pfn)
+               end = max_arch_pfn;
+
        start &= PAGE_SECTION_MASK;
        for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION) {
                unsigned long section = pfn_to_section_nr(pfn);
@@ -196,17 +209,18 @@ static unsigned long sparse_encode_mem_map(struct page *mem_map, unsigned long p
 }
 
 /*
- * We need this if we ever free the mem_maps.  While not implemented yet,
- * this function is included for parity with its sibling.
+ * Decode mem_map from the coded memmap
  */
-static __attribute((unused))
 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 pnum, struct page *mem_map,
+               unsigned long *pageblock_bitmap)
 {
        if (!present_section(ms))
                return -EINVAL;
@@ -214,18 +228,45 @@ static int __meminit sparse_init_one_section(struct mem_section *ms,
        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;
 }
 
-__attribute__((weak)) __init
-void *alloc_bootmem_high_node(pg_data_t *pgdat, unsigned long size)
+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 */
+
+static unsigned long *__init sparse_early_usemap_alloc(unsigned long pnum)
 {
+       unsigned long *usemap;
+       struct mem_section *ms = __nr_to_section(pnum);
+       int nid = sparse_early_nid(ms);
+
+       usemap = alloc_bootmem_node(NODE_DATA(nid), usemap_size());
+       if (usemap)
+               return usemap;
+
+       /* Stupid: suppress gcc warning for SPARSEMEM && !NUMA */
+       nid = 0;
+
+       printk(KERN_WARNING "%s: allocation failed\n", __func__);
        return NULL;
 }
 
 #ifndef CONFIG_SPARSEMEM_VMEMMAP
-struct page __init *sparse_early_mem_map_populate(unsigned long pnum, int nid)
+struct page __init *sparse_mem_map_populate(unsigned long pnum, int nid)
 {
        struct page *map;
 
@@ -233,13 +274,8 @@ struct page __init *sparse_early_mem_map_populate(unsigned long pnum, int nid)
        if (map)
                return map;
 
-       map = alloc_bootmem_high_node(NODE_DATA(nid),
-                       sizeof(struct page) * PAGES_PER_SECTION);
-       if (map)
-               return map;
-
-       map = alloc_bootmem_node(NODE_DATA(nid),
-                       sizeof(struct page) * PAGES_PER_SECTION);
+       map = alloc_bootmem_pages_node(NODE_DATA(nid),
+                      PAGE_ALIGN(sizeof(struct page) * PAGES_PER_SECTION));
        return map;
 }
 #endif /* !CONFIG_SPARSEMEM_VMEMMAP */
@@ -250,16 +286,19 @@ struct page __init *sparse_early_mem_map_alloc(unsigned long pnum)
        struct mem_section *ms = __nr_to_section(pnum);
        int nid = sparse_early_nid(ms);
 
-       map = sparse_early_mem_map_populate(pnum, nid);
+       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", __FUNCTION__);
+                       "some memory will not be available.\n", __func__);
        ms->section_mem_map = 0;
        return NULL;
 }
 
+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.
@@ -268,19 +307,69 @@ void __init sparse_init(void)
 {
        unsigned long pnum;
        struct page *map;
+       unsigned long *usemap;
+       unsigned long **usemap_map;
+       int size;
+
+       /*
+        * 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 continously.
+        *
+        * 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++) {
                if (!present_section_nr(pnum))
                        continue;
+               usemap_map[pnum] = sparse_early_usemap_alloc(pnum);
+       }
+
+       for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) {
+               if (!present_section_nr(pnum))
+                       continue;
+
+               usemap = usemap_map[pnum];
+               if (!usemap)
+                       continue;
 
                map = sparse_early_mem_map_alloc(pnum);
                if (!map)
                        continue;
-               sparse_init_one_section(__nr_to_section(pnum), pnum, map);
+
+               sparse_init_one_section(__nr_to_section(pnum), pnum, map,
+                                                               usemap);
        }
+
+       vmemmap_populate_print_last();
+
+       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;
@@ -303,23 +392,83 @@ got_map_ptr:
        return ret;
 }
 
-static int vaddr_in_vmalloc_area(void *addr)
+static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid,
+                                                 unsigned long nr_pages)
 {
-       if (addr >= (void *)VMALLOC_START &&
-           addr < (void *)VMALLOC_END)
-               return 1;
-       return 0;
+       return __kmalloc_section_memmap(nr_pages);
 }
 
 static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages)
 {
-       if (vaddr_in_vmalloc_area(memmap))
+       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;
+       int magic;
+
+       for (i = 0; i < nr_pages; i++, page++) {
+               magic = atomic_read(&page->_mapcount);
+
+               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
@@ -332,6 +481,7 @@ int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
        struct pglist_data *pgdat = zone->zone_pgdat;
        struct mem_section *ms;
        struct page *memmap;
+       unsigned long *usemap;
        unsigned long flags;
        int ret;
 
@@ -339,8 +489,17 @@ int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
         * no locking for this, because it does its own
         * plus, it does a kmalloc
         */
-       sparse_index_init(section_nr, pgdat->node_id);
-       memmap = __kmalloc_section_memmap(nr_pages);
+       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);
 
@@ -349,14 +508,33 @@ int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
                ret = -EEXIST;
                goto out;
        }
+
        ms->section_mem_map |= SECTION_MARKED_PRESENT;
 
-       ret = sparse_init_one_section(ms, section_nr, memmap);
+       ret = sparse_init_one_section(ms, section_nr, memmap, usemap);
 
 out:
        pgdat_resize_unlock(pgdat, &flags);
-       if (ret <= 0)
+       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