This is a note to let you know that I've just added the patch titled
block: don't ignore REQ_NOWAIT for direct IO
to the 5.11-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
block-don-t-ignore-req_nowait-for-direct-io.patch
and it can be found in the queue-5.11 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 92c0a494034700c408e50c07f38d4b2eb19db25b
Author: Pavel Begunkov <asml.silence@xxxxxxxxx>
Date: Fri Nov 20 17:10:28 2020 +0000
block: don't ignore REQ_NOWAIT for direct IO
[ 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@xxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 85500e2400cf..b988f78ad4b7 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -276,6 +276,8 @@ __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);
@@ -429,6 +431,8 @@ __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;
