diff options
author | Nick Piggin <npiggin@suse.de> | 2006-03-22 00:08:40 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-03-22 07:54:02 -0800 |
commit | 7835e98b2e3c66dba79cb0ff8ebb90a2fe030c29 (patch) | |
tree | 405a96eade34845dabe2f125b6c5eb095846869d /mm | |
parent | 70dc991d66cac40fdb07346dba2b5d862d732c34 (diff) |
[PATCH] remove set_page_count() outside mm/
set_page_count usage outside mm/ is limited to setting the refcount to 1.
Remove set_page_count from outside mm/, and replace those users with
init_page_count() and set_page_refcounted().
This allows more debug checking, and tighter control on how code is allowed
to play around with page->_count.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'mm')
-rw-r--r-- | mm/hugetlb.c | 5 | ||||
-rw-r--r-- | mm/internal.h | 13 | ||||
-rw-r--r-- | mm/page_alloc.c | 14 |
3 files changed, 21 insertions, 11 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 39d49ecea8e8..20117a4b8ab6 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -18,6 +18,7 @@ #include <asm/pgtable.h> #include <linux/hugetlb.h> +#include "internal.h" const unsigned long hugetlb_zero = 0, hugetlb_infinity = ~0UL; static unsigned long nr_huge_pages, free_huge_pages; @@ -106,7 +107,7 @@ struct page *alloc_huge_page(struct vm_area_struct *vma, unsigned long addr) return NULL; } spin_unlock(&hugetlb_lock); - set_page_count(page, 1); + set_page_refcounted(page); for (i = 0; i < (HPAGE_SIZE/PAGE_SIZE); ++i) clear_user_highpage(&page[i], addr); return page; @@ -152,7 +153,7 @@ static void update_and_free_page(struct page *page) 1 << PG_private | 1<< PG_writeback); } page[1].lru.next = NULL; - set_page_count(page, 1); + set_page_refcounted(page); __free_pages(page, HUGETLB_PAGE_ORDER); } diff --git a/mm/internal.h b/mm/internal.h index 7bb339779818..d20e3cc4aef0 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -13,8 +13,19 @@ #include <linux/mm.h> -static inline void set_page_refs(struct page *page, int order) +static inline void set_page_count(struct page *page, int v) { + atomic_set(&page->_count, v); +} + +/* + * Turn a non-refcounted page (->_count == 0) into refcounted with + * a count of one. + */ +static inline void set_page_refcounted(struct page *page) +{ + BUG_ON(PageCompound(page) && page_private(page) != (unsigned long)page); + BUG_ON(atomic_read(&page->_count)); set_page_count(page, 1); } diff --git a/mm/page_alloc.c b/mm/page_alloc.c index e197818a7cf6..7f65b5a63bb3 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -442,7 +442,7 @@ void fastcall __init __free_pages_bootmem(struct page *page, unsigned int order) if (order == 0) { __ClearPageReserved(page); set_page_count(page, 0); - set_page_refs(page, 0); + set_page_refcounted(page); __free_page(page); } else { int loop; @@ -457,7 +457,7 @@ void fastcall __init __free_pages_bootmem(struct page *page, unsigned int order) set_page_count(p, 0); } - set_page_refs(page, order); + set_page_refcounted(page); __free_pages(page, order); } } @@ -525,7 +525,7 @@ static int prep_new_page(struct page *page, int order) 1 << PG_referenced | 1 << PG_arch_1 | 1 << PG_checked | 1 << PG_mappedtodisk); set_page_private(page, 0); - set_page_refs(page, order); + set_page_refcounted(page); kernel_map_pages(page, 1 << order, 1); return 0; } @@ -755,10 +755,8 @@ void split_page(struct page *page, unsigned int order) BUG_ON(PageCompound(page)); BUG_ON(!page_count(page)); - for (i = 1; i < (1 << order); i++) { - BUG_ON(page_count(page + i)); - set_page_count(page + i, 1); - } + for (i = 1; i < (1 << order); i++) + set_page_refcounted(page + i); } /* @@ -1771,7 +1769,7 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, continue; page = pfn_to_page(pfn); set_page_links(page, zone, nid, pfn); - set_page_count(page, 1); + init_page_count(page); reset_page_mapcount(page); SetPageReserved(page); INIT_LIST_HEAD(&page->lru); |