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author | Damien Le Moal <damien.lemoal@wdc.com> | 2018-02-28 09:35:29 -0800 |
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committer | Jens Axboe <axboe@kernel.dk> | 2018-03-01 08:39:24 -0700 |
commit | f3bc78d2d4b489590540ab2788d5376583e28173 (patch) | |
tree | 0a6dd46bd1feef14581a7fd0ddc7d704a54c4952 | |
parent | 468f098734ab095b72d8af26bcd4bcb2ed31a3be (diff) | |
download | linux-f3bc78d2d4b489590540ab2788d5376583e28173.tar.gz linux-f3bc78d2d4b489590540ab2788d5376583e28173.tar.bz2 linux-f3bc78d2d4b489590540ab2788d5376583e28173.zip |
mq-deadline: Make sure to always unlock zones
In case of a failed write request (all retries failed) and when using
libata, the SCSI error handler calls scsi_finish_command(). In the
case of blk-mq this means that scsi_mq_done() does not get called,
that blk_mq_complete_request() does not get called and also that the
mq-deadline .completed_request() method is not called. This results in
the target zone of the failed write request being left in a locked
state, preventing that any new write requests are issued to the same
zone.
Fix this by replacing the .completed_request() method with the
.finish_request() method as this method is always called whether or
not a request completes successfully. Since the .finish_request()
method is only called by the blk-mq core if a .prepare_request()
method exists, add a dummy .prepare_request() method.
Fixes: 5700f69178e9 ("mq-deadline: Introduce zone locking support")
Cc: Hannes Reinecke <hare@suse.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
[ bvanassche: edited patch description ]
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-rw-r--r-- | block/mq-deadline.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/block/mq-deadline.c b/block/mq-deadline.c index c56f211c8440..8ec0ba9f5386 100644 --- a/block/mq-deadline.c +++ b/block/mq-deadline.c @@ -536,12 +536,21 @@ static void dd_insert_requests(struct blk_mq_hw_ctx *hctx, } /* + * Nothing to do here. This is defined only to ensure that .finish_request + * method is called upon request completion. + */ +static void dd_prepare_request(struct request *rq, struct bio *bio) +{ +} + +/* * For zoned block devices, write unlock the target zone of * completed write requests. Do this while holding the zone lock * spinlock so that the zone is never unlocked while deadline_fifo_request() - * while deadline_next_request() are executing. + * or deadline_next_request() are executing. This function is called for + * all requests, whether or not these requests complete successfully. */ -static void dd_completed_request(struct request *rq) +static void dd_finish_request(struct request *rq) { struct request_queue *q = rq->q; @@ -756,7 +765,8 @@ static struct elevator_type mq_deadline = { .ops.mq = { .insert_requests = dd_insert_requests, .dispatch_request = dd_dispatch_request, - .completed_request = dd_completed_request, + .prepare_request = dd_prepare_request, + .finish_request = dd_finish_request, .next_request = elv_rb_latter_request, .former_request = elv_rb_former_request, .bio_merge = dd_bio_merge, |