From 39f985c8f667c80a3d1eb19d31138032fa36b09e Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Sat, 20 Mar 2021 05:40:38 +0000 Subject: fs/cachefiles: Remove wait_bit_key layout dependency Cachefiles was relying on wait_page_key and wait_bit_key being the same layout, which is fragile. Now that wait_page_key is exposed in the pagemap.h header, we can remove that fragility A comment on the need to maintain structure layout equivalence was added by Linus[1] and that is no longer applicable. Fixes: 62906027091f ("mm: add PageWaiters indicating tasks are waiting for a page bit") Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig Signed-off-by: David Howells Tested-by: kafs-testing@auristor.com cc: linux-cachefs@redhat.com cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20210320054104.1300774-2-willy@infradead.org/ Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=3510ca20ece0150af6b10c77a74ff1b5c198e3e2 [1] --- include/linux/pagemap.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include') diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 20225b067583..8f4daac6eb4b 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -559,7 +559,6 @@ static inline pgoff_t linear_page_index(struct vm_area_struct *vma, return pgoff; } -/* This has the same layout as wait_bit_key - see fs/cachefiles/rdwr.c */ struct wait_page_key { struct page *page; int bit_nr; -- cgit v1.2.3 From e5dbd33218bd8d87ab69f730ab90aed5fab7eb26 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Sat, 20 Mar 2021 05:40:39 +0000 Subject: mm/writeback: Add wait_on_page_writeback_killable This is the killable version of wait_on_page_writeback. Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig Signed-off-by: David Howells Tested-by: kafs-testing@auristor.com cc: linux-afs@lists.infradead.org cc: linux-mm@kvack.org Link: https://lore.kernel.org/r/20210320054104.1300774-3-willy@infradead.org --- include/linux/pagemap.h | 1 + mm/page-writeback.c | 16 ++++++++++++++++ 2 files changed, 17 insertions(+) (limited to 'include') diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 8f4daac6eb4b..8c9947fd62f3 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -682,6 +682,7 @@ static inline int wait_on_page_locked_killable(struct page *page) int put_and_wait_on_page_locked(struct page *page, int state); void wait_on_page_writeback(struct page *page); +int wait_on_page_writeback_killable(struct page *page); extern void end_page_writeback(struct page *page); void wait_for_stable_page(struct page *page); diff --git a/mm/page-writeback.c b/mm/page-writeback.c index eb34d204d4ee..9e35b636a393 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2833,6 +2833,22 @@ void wait_on_page_writeback(struct page *page) } EXPORT_SYMBOL_GPL(wait_on_page_writeback); +/* + * Wait for a page to complete writeback. Returns -EINTR if we get a + * fatal signal while waiting. + */ +int wait_on_page_writeback_killable(struct page *page) +{ + while (PageWriteback(page)) { + trace_wait_on_page_writeback(page, page_mapping(page)); + if (wait_on_page_bit_killable(page, PG_writeback)) + return -EINTR; + } + + return 0; +} +EXPORT_SYMBOL_GPL(wait_on_page_writeback_killable); + /** * wait_for_stable_page() - wait for writeback to finish, if necessary. * @page: The page to wait on. -- cgit v1.2.3