From: Yu Kuai yukuai3@huawei.com
[ Upstream commit 2895f1831e911ca87d4efdf43e35eb72a0c7e66e ]
Otherwise io will hung because request will only be completed if the cmd has the flag 'NBD_CMD_INFLIGHT'.
Fixes: 07175cb1baf4 ("nbd: make sure request completion won't concurrent") Signed-off-by: Yu Kuai yukuai3@huawei.com Link: https://lore.kernel.org/r/20220521073749.3146892-4-yukuai3@huawei.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/block/nbd.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-)
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 284557041336..ed678037ba6d 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -404,13 +404,14 @@ static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req, if (!mutex_trylock(&cmd->lock)) return BLK_EH_RESET_TIMER;
- if (!__test_and_clear_bit(NBD_CMD_INFLIGHT, &cmd->flags)) { + if (!test_bit(NBD_CMD_INFLIGHT, &cmd->flags)) { mutex_unlock(&cmd->lock); return BLK_EH_DONE; }
if (!refcount_inc_not_zero(&nbd->config_refs)) { cmd->status = BLK_STS_TIMEOUT; + __clear_bit(NBD_CMD_INFLIGHT, &cmd->flags); mutex_unlock(&cmd->lock); goto done; } @@ -479,6 +480,7 @@ static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req, dev_err_ratelimited(nbd_to_dev(nbd), "Connection timed out\n"); set_bit(NBD_RT_TIMEDOUT, &config->runtime_flags); cmd->status = BLK_STS_IOERR; + __clear_bit(NBD_CMD_INFLIGHT, &cmd->flags); mutex_unlock(&cmd->lock); sock_shutdown(nbd); nbd_config_put(nbd); @@ -746,7 +748,7 @@ static struct nbd_cmd *nbd_handle_reply(struct nbd_device *nbd, int index, cmd = blk_mq_rq_to_pdu(req);
mutex_lock(&cmd->lock); - if (!__test_and_clear_bit(NBD_CMD_INFLIGHT, &cmd->flags)) { + if (!test_bit(NBD_CMD_INFLIGHT, &cmd->flags)) { dev_err(disk_to_dev(nbd->disk), "Suspicious reply %d (status %u flags %lu)", tag, cmd->status, cmd->flags); ret = -ENOENT; @@ -855,8 +857,16 @@ static void recv_work(struct work_struct *work) }
rq = blk_mq_rq_from_pdu(cmd); - if (likely(!blk_should_fake_timeout(rq->q))) - blk_mq_complete_request(rq); + if (likely(!blk_should_fake_timeout(rq->q))) { + bool complete; + + mutex_lock(&cmd->lock); + complete = __test_and_clear_bit(NBD_CMD_INFLIGHT, + &cmd->flags); + mutex_unlock(&cmd->lock); + if (complete) + blk_mq_complete_request(rq); + } percpu_ref_put(&q->q_usage_counter); }