From a4796e37c12e177572b80864cbab9c907ea250b0 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Wed, 24 Sep 2014 11:28:32 +1000 Subject: [PATCH] MM: export page_wakeup functions This will allow NFS to wait for PG_private to be cleared and, particularly, to send a wake-up when it is. Signed-off-by: NeilBrown Acked-by: Andrew Morton Signed-off-by: Trond Myklebust --- include/linux/pagemap.h | 10 ++++++++-- mm/filemap.c | 8 ++------ 2 files changed, 10 insertions(+), 8 deletions(-) diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 87f9e42..2dca0ce 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -496,8 +496,8 @@ static inline int lock_page_or_retry(struct page *page, struct mm_struct *mm, } /* - * This is exported only for wait_on_page_locked/wait_on_page_writeback. - * Never use this directly! + * This is exported only for wait_on_page_locked/wait_on_page_writeback, + * and for filesystems which need to wait on PG_private. */ extern void wait_on_page_bit(struct page *page, int bit_nr); @@ -512,6 +512,12 @@ static inline int wait_on_page_locked_killable(struct page *page) return 0; } +extern wait_queue_head_t *page_waitqueue(struct page *page); +static inline void wake_up_page(struct page *page, int bit) +{ + __wake_up_bit(page_waitqueue(page), &page->flags, bit); +} + /* * Wait for a page to be unlocked. * diff --git a/mm/filemap.c b/mm/filemap.c index cbe5a90..b9b1413 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -670,17 +670,13 @@ EXPORT_SYMBOL(__page_cache_alloc); * at a cost of "thundering herd" phenomena during rare hash * collisions. */ -static wait_queue_head_t *page_waitqueue(struct page *page) +wait_queue_head_t *page_waitqueue(struct page *page) { const struct zone *zone = page_zone(page); return &zone->wait_table[hash_ptr(page, zone->wait_table_bits)]; } - -static inline void wake_up_page(struct page *page, int bit) -{ - __wake_up_bit(page_waitqueue(page), &page->flags, bit); -} +EXPORT_SYMBOL(page_waitqueue); void wait_on_page_bit(struct page *page, int bit_nr) { -- 2.7.4