NVMe: Requeue requests on suspended queues

It's possible a request may get to the driver after the nvme queue was
disabled. This has the request requeue if that happens.

Note the request is still "started" by the driver, but requeuing will
clear the start state for timeout handling.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 72ef8322d32ac7180912e2ae2cf38245f3713d9a..e5c2bea01dbf55365aad109e0dd80c1f699dddfe 100644 (file)
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -678,6 +678,11 @@ static int nvme_queue_rq(struct blk_mq_hw_ctx *hctx,
        blk_mq_start_request(req);
 
        spin_lock_irq(&nvmeq->q_lock);
+       if (unlikely(nvmeq->cq_vector < 0)) {
+               ret = BLK_MQ_RQ_QUEUE_BUSY;
+               spin_unlock_irq(&nvmeq->q_lock);
+               goto out;
+       }
        __nvme_submit_cmd(nvmeq, &cmnd);
        nvme_process_cq(nvmeq);
        spin_unlock_irq(&nvmeq->q_lock);