6.14-stable review patch. If anyone has any objections, please let me know.
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From: Ming Lei ming.lei@redhat.com
[ Upstream commit 7e26cb69c5e62152a6f05a2ae23605a983a8ef31 ]
Now ublk deals with ublk_nosrv_dev_should_queue_io() by keeping request queue as quiesced. This way is fragile because queue quiesce crosses syscalls or process contexts.
Switch to rely on ubq->canceling for dealing with ublk_nosrv_dev_should_queue_io(), because it has been used for this purpose during io_uring context exiting, and it can be reused before recovering too. In ublk_queue_rq(), the request will be added to requeue list without kicking off requeue in case of ubq->canceling, and finally requests added in requeue list will be dispatched from either ublk_stop_dev() or ublk_ctrl_end_recovery().
Meantime we have to move reset of ubq->canceling from ublk_ctrl_start_recovery() to ublk_ctrl_end_recovery(), when IO handling can be recovered completely.
Then blk_mq_quiesce_queue() and blk_mq_unquiesce_queue() are always used in same context.
Signed-off-by: Ming Lei ming.lei@redhat.com Reviewed-by: Uday Shankar ushankar@purestorage.com Link: https://lore.kernel.org/r/20250416035444.99569-4-ming.lei@redhat.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/block/ublk_drv.c | 31 +++++++++++++++++-------------- 1 file changed, 17 insertions(+), 14 deletions(-)
diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index 7bb7276f14c60..0efac33473c1e 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -1698,13 +1698,19 @@ static void ublk_wait_tagset_rqs_idle(struct ublk_device *ub)
static void __ublk_quiesce_dev(struct ublk_device *ub) { + int i; + pr_devel("%s: quiesce ub: dev_id %d state %s\n", __func__, ub->dev_info.dev_id, ub->dev_info.state == UBLK_S_DEV_LIVE ? "LIVE" : "QUIESCED"); blk_mq_quiesce_queue(ub->ub_disk->queue); + /* mark every queue as canceling */ + for (i = 0; i < ub->dev_info.nr_hw_queues; i++) + ublk_get_queue(ub, i)->canceling = true; ublk_wait_tagset_rqs_idle(ub); ub->dev_info.state = UBLK_S_DEV_QUIESCED; + blk_mq_unquiesce_queue(ub->ub_disk->queue); }
static void ublk_force_abort_dev(struct ublk_device *ub) @@ -2846,7 +2852,6 @@ static void ublk_queue_reinit(struct ublk_device *ub, struct ublk_queue *ubq) /* We have to reset it to NULL, otherwise ub won't accept new FETCH_REQ */ ubq->ubq_daemon = NULL; ubq->timeout = false; - ubq->canceling = false;
for (i = 0; i < ubq->q_depth; i++) { struct ublk_io *io = &ubq->ios[i]; @@ -2935,20 +2940,18 @@ static int ublk_ctrl_end_recovery(struct ublk_device *ub, pr_devel("%s: new ublksrv_pid %d, dev id %d\n", __func__, ublksrv_pid, header->dev_id);
- if (ublk_nosrv_dev_should_queue_io(ub)) { - ub->dev_info.state = UBLK_S_DEV_LIVE; - blk_mq_unquiesce_queue(ub->ub_disk->queue); - pr_devel("%s: queue unquiesced, dev id %d.\n", - __func__, header->dev_id); - blk_mq_kick_requeue_list(ub->ub_disk->queue); - } else { - blk_mq_quiesce_queue(ub->ub_disk->queue); - ub->dev_info.state = UBLK_S_DEV_LIVE; - for (i = 0; i < ub->dev_info.nr_hw_queues; i++) { - ublk_get_queue(ub, i)->fail_io = false; - } - blk_mq_unquiesce_queue(ub->ub_disk->queue); + blk_mq_quiesce_queue(ub->ub_disk->queue); + ub->dev_info.state = UBLK_S_DEV_LIVE; + for (i = 0; i < ub->dev_info.nr_hw_queues; i++) { + struct ublk_queue *ubq = ublk_get_queue(ub, i); + + ubq->canceling = false; + ubq->fail_io = false; } + blk_mq_unquiesce_queue(ub->ub_disk->queue); + pr_devel("%s: queue unquiesced, dev id %d.\n", + __func__, header->dev_id); + blk_mq_kick_requeue_list(ub->ub_disk->queue);
ret = 0; out_unlock: