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-rw-r--r--mm/sparse.c145
1 files changed, 134 insertions, 11 deletions
diff --git a/mm/sparse.c b/mm/sparse.c
index 98d6b39c..dff71f1 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -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>
@@ -208,12 +209,12 @@ 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);
}
@@ -232,7 +233,7 @@ static int __meminit sparse_init_one_section(struct mem_section *ms,
return 1;
}
-static unsigned long usemap_size(void)
+unsigned long usemap_size(void)
{
unsigned long size_bytes;
size_bytes = roundup(SECTION_BLOCKFLAGS_BITS, 8) / 8;
@@ -249,11 +250,22 @@ static unsigned long *__kmalloc_section_usemap(void)
static unsigned long *__init sparse_early_usemap_alloc(unsigned long pnum)
{
- unsigned long *usemap;
+ unsigned long *usemap, section_nr;
struct mem_section *ms = __nr_to_section(pnum);
int nid = sparse_early_nid(ms);
+ struct pglist_data *pgdat = NODE_DATA(nid);
- usemap = alloc_bootmem_node(NODE_DATA(nid), usemap_size());
+ /*
+ * Usemap's page can't be freed until freeing other sections
+ * which use it. And, Pgdat has same feature.
+ * If section A has pgdat and section B has usemap for other
+ * sections (includes section A), both sections can't be removed,
+ * because there is the dependency each other.
+ * To solve above issue, this collects all usemap on the same section
+ * which has pgdat.
+ */
+ section_nr = pfn_to_section_nr(__pa(pgdat) >> PAGE_SHIFT);
+ usemap = alloc_bootmem_section(usemap_size(), section_nr);
if (usemap)
return usemap;
@@ -273,8 +285,8 @@ struct page __init *sparse_mem_map_populate(unsigned long pnum, int nid)
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 */
@@ -295,6 +307,9 @@ struct page __init *sparse_early_mem_map_alloc(unsigned long pnum)
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.
@@ -304,22 +319,50 @@ 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);
+ }
- map = sparse_early_mem_map_alloc(pnum);
- if (!map)
+ for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) {
+ if (!present_section_nr(pnum))
continue;
- usemap = sparse_early_usemap_alloc(pnum);
+ 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,
usemap);
}
+
+ vmemmap_populate_print_last();
+
+ free_bootmem(__pa(usemap_map), size);
}
#ifdef CONFIG_MEMORY_HOTPLUG
@@ -334,6 +377,9 @@ 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)
{
@@ -371,8 +417,69 @@ static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages)
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
@@ -425,4 +532,20 @@ out:
}
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