diff options
Diffstat (limited to 'mm/debug-pagealloc.c')
| -rw-r--r-- | mm/debug-pagealloc.c | 102 |
1 files changed, 0 insertions, 102 deletions
diff --git a/mm/debug-pagealloc.c b/mm/debug-pagealloc.c deleted file mode 100644 index 789ff70c8a4a..000000000000 --- a/mm/debug-pagealloc.c +++ /dev/null @@ -1,102 +0,0 @@ -#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> - -static inline void set_page_poison(struct page *page) -{ - __set_bit(PAGE_DEBUG_FLAG_POISON, &page->debug_flags); -} - -static inline void clear_page_poison(struct page *page) -{ - __clear_bit(PAGE_DEBUG_FLAG_POISON, &page->debug_flags); -} - -static inline bool page_poison(struct page *page) -{ - return test_bit(PAGE_DEBUG_FLAG_POISON, &page->debug_flags); -} - -static void poison_page(struct page *page) -{ - void *addr = kmap_atomic(page); - - set_page_poison(page); - memset(addr, PAGE_POISON, PAGE_SIZE); - kunmap_atomic(addr); -} - -static void poison_pages(struct page *page, int n) -{ - int i; - - for (i = 0; i < n; i++) - poison_page(page + i); -} - -static bool single_bit_flip(unsigned char a, unsigned char b) -{ - unsigned char error = a ^ b; - - return error && !(error & (error - 1)); -} - -static void check_poison_mem(unsigned char *mem, size_t bytes) -{ - static DEFINE_RATELIMIT_STATE(ratelimit, 5 * HZ, 10); - unsigned char *start; - unsigned char *end; - - start = memchr_inv(mem, PAGE_POISON, bytes); - if (!start) - return; - - for (end = mem + bytes - 1; end > start; end--) { - if (*end != PAGE_POISON) - break; - } - - if (!__ratelimit(&ratelimit)) - return; - else if (start == end && single_bit_flip(*start, PAGE_POISON)) - printk(KERN_ERR "pagealloc: single bit error\n"); - else - printk(KERN_ERR "pagealloc: memory corruption\n"); - - print_hex_dump(KERN_ERR, "", DUMP_PREFIX_ADDRESS, 16, 1, start, - end - start + 1, 1); - dump_stack(); -} - -static void unpoison_page(struct page *page) -{ - void *addr; - - if (!page_poison(page)) - return; - - 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) -{ - int i; - - for (i = 0; i < n; i++) - unpoison_page(page + i); -} - -void kernel_map_pages(struct page *page, int numpages, int enable) -{ - if (enable) - unpoison_pages(page, numpages); - else - poison_pages(page, numpages); -} |
