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-rw-r--r--mm/debug-pagealloc.c137
1 files changed, 0 insertions, 137 deletions
diff --git a/mm/debug-pagealloc.c b/mm/debug-pagealloc.c
deleted file mode 100644
index 5bf5906ce13b..000000000000
--- a/mm/debug-pagealloc.c
+++ /dev/null
@@ -1,137 +0,0 @@
-#include <linux/kernel.h>
-#include <linux/string.h>
-#include <linux/mm.h>
-#include <linux/highmem.h>
-#include <linux/page_ext.h>
-#include <linux/poison.h>
-#include <linux/ratelimit.h>
-
-static bool page_poisoning_enabled __read_mostly;
-
-static bool need_page_poisoning(void)
-{
- if (!debug_pagealloc_enabled())
- return false;
-
- return true;
-}
-
-static void init_page_poisoning(void)
-{
- if (!debug_pagealloc_enabled())
- return;
-
- page_poisoning_enabled = true;
-}
-
-struct page_ext_operations page_poisoning_ops = {
- .need = need_page_poisoning,
- .init = init_page_poisoning,
-};
-
-static inline void set_page_poison(struct page *page)
-{
- struct page_ext *page_ext;
-
- page_ext = lookup_page_ext(page);
- __set_bit(PAGE_EXT_DEBUG_POISON, &page_ext->flags);
-}
-
-static inline void clear_page_poison(struct page *page)
-{
- struct page_ext *page_ext;
-
- page_ext = lookup_page_ext(page);
- __clear_bit(PAGE_EXT_DEBUG_POISON, &page_ext->flags);
-}
-
-static inline bool page_poison(struct page *page)
-{
- struct page_ext *page_ext;
-
- page_ext = lookup_page_ext(page);
- return test_bit(PAGE_EXT_DEBUG_POISON, &page_ext->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 (!page_poisoning_enabled)
- return;
-
- if (enable)
- unpoison_pages(page, numpages);
- else
- poison_pages(page, numpages);
-}