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| author | Akinobu Mita <akinobu.mita@gmail.com> | 2011-11-01 04:08:38 +0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-11-01 04:30:48 +0400 |
| commit | 64212ec569bfdd094f7a23d9b09862209a983559 (patch) | |
| tree | af9a80c08795e602c5a6401fa3599562c2b6be48 /mm | |
| parent | 3ee9a4f086716d792219c021e8509f91165a4128 (diff) | |
| download | linux-64212ec569bfdd094f7a23d9b09862209a983559.tar.xz | |
debug-pagealloc: add support for highmem pages
This adds support for highmem pages poisoning and verification to the
debug-pagealloc feature for no-architecture support.
[akpm@linux-foundation.org: remove unneeded preempt_disable/enable]
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/debug-pagealloc.c | 44 |
1 files changed, 10 insertions, 34 deletions
diff --git a/mm/debug-pagealloc.c b/mm/debug-pagealloc.c index 2618933efdb3..7cea557407f4 100644 --- a/mm/debug-pagealloc.c +++ b/mm/debug-pagealloc.c @@ -1,6 +1,7 @@ #include <linux/kernel.h> #include <linux/string.h> #include <linux/mm.h> +#include <linux/highmem.h> #include <linux/page-debug-flags.h> #include <linux/poison.h> #include <linux/ratelimit.h> @@ -20,28 +21,13 @@ static inline bool page_poison(struct page *page) return test_bit(PAGE_DEBUG_FLAG_POISON, &page->debug_flags); } -static void poison_highpage(struct page *page) -{ - /* - * Page poisoning for highmem pages is not implemented. - * - * This can be called from interrupt contexts. - * So we need to create a new kmap_atomic slot for this - * application and it will need interrupt protection. - */ -} - static void poison_page(struct page *page) { - void *addr; + void *addr = kmap_atomic(page); - if (PageHighMem(page)) { - poison_highpage(page); - return; - } set_page_poison(page); - addr = page_address(page); memset(addr, PAGE_POISON, PAGE_SIZE); + kunmap_atomic(addr); } static void poison_pages(struct page *page, int n) @@ -86,27 +72,17 @@ static void check_poison_mem(unsigned char *mem, size_t bytes) dump_stack(); } -static void unpoison_highpage(struct page *page) -{ - /* - * See comment in poison_highpage(). - * Highmem pages should not be poisoned for now - */ - BUG_ON(page_poison(page)); -} - static void unpoison_page(struct page *page) { - if (PageHighMem(page)) { - unpoison_highpage(page); + void *addr; + + if (!page_poison(page)) return; - } - if (page_poison(page)) { - void *addr = page_address(page); - check_poison_mem(addr, PAGE_SIZE); - clear_page_poison(page); - } + addr = kmap_atomic(page); + check_poison_mem(addr, PAGE_SIZE); + clear_page_poison(page); + kunmap_atomic(addr); } static void unpoison_pages(struct page *page, int n) |