diff options
Diffstat (limited to 'include/linux/page-flags.h')
| -rw-r--r-- | include/linux/page-flags.h | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 96326594e55..a1e14363494 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -94,6 +94,12 @@ /* PG_owner_priv_1 users should have descriptive aliases */ #define PG_checked PG_owner_priv_1 /* Used by some filesystems */ +/* + * Marks tail portion of a compound page. We currently do not reclaim + * compound pages so we can reuse a flag only used for reclaim here. + */ +#define PG_tail PG_reclaim + #if (BITS_PER_LONG > 32) /* * 64-bit-only flags build down from bit 31 @@ -241,6 +247,14 @@ static inline void SetPageUptodate(struct page *page) #define __SetPageCompound(page) __set_bit(PG_compound, &(page)->flags) #define __ClearPageCompound(page) __clear_bit(PG_compound, &(page)->flags) +/* + * Note: PG_tail is an alias of another page flag. The result of PageTail() + * is only valid if PageCompound(page) is true. + */ +#define PageTail(page) test_bit(PG_tail, &(page)->flags) +#define __SetPageTail(page) __set_bit(PG_tail, &(page)->flags) +#define __ClearPageTail(page) __clear_bit(PG_tail, &(page)->flags) + #ifdef CONFIG_SWAP #define PageSwapCache(page) test_bit(PG_swapcache, &(page)->flags) #define SetPageSwapCache(page) set_bit(PG_swapcache, &(page)->flags) |