From 80c1fe902691d3ef4786f9e62e47a0aa0deb8b54 Mon Sep 17 00:00:00 2001 From: Konstantin Khlebnikov Date: Sat, 30 Nov 2019 17:49:41 -0800 Subject: [PATCH] mm/filemap.c: remove redundant cache invalidation after async direct-io write generic_file_direct_write() invalidates cache at entry. Second time this should be done when request completes. But this function calls second invalidation at exit unconditionally even for async requests. This patch skips second invalidation for async requests (-EIOCBQUEUED). Link: http://lkml.kernel.org/r/157270037850.4812.15036239021726025572.stgit@buzz Signed-off-by: Konstantin Khlebnikov Reviewed-by: Andrew Morton Reviewed-by: Jan Kara Cc: Jens Axboe Cc: Alexander Viro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/filemap.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/mm/filemap.c b/mm/filemap.c index 85b7d08..288e381 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -3218,9 +3218,11 @@ generic_file_direct_write(struct kiocb *iocb, struct iov_iter *from) * Most of the time we do not need this since dio_complete() will do * the invalidation for us. However there are some file systems that * do not end up with dio_complete() being called, so let's not break - * them by removing it completely + * them by removing it completely. + * + * Skip invalidation for async writes or if mapping has no pages. */ - if (mapping->nrpages) + if (written > 0 && mapping->nrpages) invalidate_inode_pages2_range(mapping, pos >> PAGE_SHIFT, end); -- 2.7.4