From 1410d2b68207cbb3bc16a4db7d655f5e06a39929 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Thu, 4 Feb 2021 16:02:10 +0100 Subject: [PATCH] Revert "Revert "block: end bio with BLK_STS_AGAIN in case of non-mq devs and REQ_NOWAIT"" This reverts commit bba91cdba612fbce4f8575c5d94d2b146fb83ea3 which is commit b0beb28097fa04177b3769f4bb7a0d0d9c4ae76e upstream. It breaks things in 5.4.y, so let's drop it. Reported-by: Andres Freund Cc: Bijan Mottahedeh CC: Jens Axboe Cc: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- block/blk-core.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index d2213220099d..5808baa950c3 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -886,11 +886,14 @@ generic_make_request_checks(struct bio *bio) } /* - * For a REQ_NOWAIT based request, return -EOPNOTSUPP - * if queue is not a request based queue. + * Non-mq queues do not honor REQ_NOWAIT, so complete a bio + * with BLK_STS_AGAIN status in order to catch -EAGAIN and + * to give a chance to the caller to repeat request gracefully. */ - if ((bio->bi_opf & REQ_NOWAIT) && !queue_is_mq(q)) - goto not_supported; + if ((bio->bi_opf & REQ_NOWAIT) && !queue_is_mq(q)) { + status = BLK_STS_AGAIN; + goto end_io; + } if (should_fail_bio(bio)) goto end_io;