From f8b78caf21d5bc3fcfc40c18898f9d52ed1451a5 Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Fri, 20 Nov 2020 17:10:28 +0000 Subject: [PATCH] block: don't ignore REQ_NOWAIT for direct IO 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 Signed-off-by: Jens Axboe --- fs/block_dev.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/block_dev.c b/fs/block_dev.c index 28d583fcdc2c..09d6f7229db9 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -275,6 +275,8 @@ __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); @@ -428,6 +430,8 @@ static ssize_t __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, 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; -- GitLab