diff options
Diffstat (limited to 'mm/sparse.c')
| -rw-r--r-- | mm/sparse.c | 108 |
1 files changed, 100 insertions, 8 deletions
diff --git a/mm/sparse.c b/mm/sparse.c index 7e9191381f86..dff71f173ae9 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 */ @@ -365,6 +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) { @@ -402,8 +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 @@ -456,4 +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 |
