From 2687a3569e40b1302f96698bcd6329aeb0ce3dd2 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Thu, 6 Dec 2007 11:18:49 -0500 Subject: Add lock_page_killable This routine is like lock_page, but can be interrupted by a fatal signal Signed-off-by: Matthew Wilcox --- include/linux/pagemap.h | 14 ++++++++++++++ mm/filemap.c | 14 ++++++++++++++ 2 files changed, 28 insertions(+) diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index db8a410ae9e..4b62a105622 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -157,6 +157,7 @@ static inline pgoff_t linear_page_index(struct vm_area_struct *vma, } extern void FASTCALL(__lock_page(struct page *page)); +extern int FASTCALL(__lock_page_killable(struct page *page)); extern void FASTCALL(__lock_page_nosync(struct page *page)); extern void FASTCALL(unlock_page(struct page *page)); @@ -170,6 +171,19 @@ static inline void lock_page(struct page *page) __lock_page(page); } +/* + * lock_page_killable is like lock_page but can be interrupted by fatal + * signals. It returns 0 if it locked the page and -EINTR if it was + * killed while waiting. + */ +static inline int lock_page_killable(struct page *page) +{ + might_sleep(); + if (TestSetPageLocked(page)) + return __lock_page_killable(page); + return 0; +} + /* * lock_page_nosync should only be used if we can't pin the page's inode. * Doesn't play quite so well with block device plugging. diff --git a/mm/filemap.c b/mm/filemap.c index 188cf5fd3e8..ac8f690d288 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -173,6 +173,12 @@ static int sync_page(void *word) return 0; } +static int sync_page_killable(void *word) +{ + sync_page(word); + return fatal_signal_pending(current) ? -EINTR : 0; +} + /** * __filemap_fdatawrite_range - start writeback on mapping dirty pages in range * @mapping: address space structure to write @@ -577,6 +583,14 @@ void fastcall __lock_page(struct page *page) } EXPORT_SYMBOL(__lock_page); +int fastcall __lock_page_killable(struct page *page) +{ + DEFINE_WAIT_BIT(wait, &page->flags, PG_locked); + + return __wait_on_bit_lock(page_waitqueue(page), &wait, + sync_page_killable, TASK_KILLABLE); +} + /* * Variant of lock_page that does not require the caller to hold a reference * on the page's mapping. -- cgit v1.2.3