[PATCH AUTOSEL 5.10 22/22] block: don't ignore REQ_NOWAIT for direct IO
From: Sasha Levin <sashal@kernel.org>
Date: 2021-04-05 16:05:12
Also in:
linux-fsdevel, lkml, stable
Subsystem:
filesystems (vfs and infrastructure), the rest · Maintainers:
Alexander Viro, Christian Brauner, Linus Torvalds
From: Pavel Begunkov <asml.silence@gmail.com> [ Upstream commit f8b78caf21d5bc3fcfc40c18898f9d52ed1451a5 ] If IOCB_NOWAIT is set on submission, then that needs to get propagated to REQ_NOWAIT on the block side. Otherwise we completely lose this information, and any issuer of IOCB_NOWAIT IO will potentially end up blocking on eg request allocation on the storage side. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org> --- fs/block_dev.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/fs/block_dev.c b/fs/block_dev.c
index fe201b757baa..1b6a34fd1fef 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c@@ -280,6 +280,8 @@ __blkdev_direct_IO_simple(struct kiocb *iocb, struct iov_iter *iter, bio.bi_opf = dio_bio_write_op(iocb); task_io_account_write(ret); } + if (iocb->ki_flags & IOCB_NOWAIT) + bio.bi_opf |= REQ_NOWAIT; if (iocb->ki_flags & IOCB_HIPRI) bio_set_polled(&bio, iocb);
@@ -433,6 +435,8 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages) bio->bi_opf = dio_bio_write_op(iocb); task_io_account_write(bio->bi_iter.bi_size); } + if (iocb->ki_flags & IOCB_NOWAIT) + bio->bi_opf |= REQ_NOWAIT; dio->size += bio->bi_iter.bi_size; pos += bio->bi_iter.bi_size;
--
2.30.2