nvme: handle connectivity loss in nvme_set_queue_count

[ Upstream commit 294b2b7516fd06a8dd82e4a6118f318ec521e706 ]

When the set feature attempts fails with any NVME status code set in
nvme_set_queue_count, the function still report success. Though the
numbers of queues set to 0. This is done to support controllers in
degraded state (the admin queue is still up and running but no IO
queues).

Though there is an exception. When nvme_set_features reports an host
path error, nvme_set_queue_count should propagate this error as the
connectivity is lost, which means also the admin queue is not working
anymore.

Fixes: 9a0be7abb62f ("nvme: refactor set_queue_count")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Daniel Wagner <wagi@kernel.org>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 17ba2e59fce26c921da3d221ab947c518cd2443c..7f744aa4d120c65c1d0ff89824fae34738a0f1c4 100644 (file)
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -1585,7 +1585,13 @@ int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count)
 
        status = nvme_set_features(ctrl, NVME_FEAT_NUM_QUEUES, q_count, NULL, 0,
                        &result);
-       if (status < 0)
+
+       /*
+        * It's either a kernel error or the host observed a connection
+        * lost. In either case it's not possible communicate with the
+        * controller and thus enter the error code path.
+        */
+       if (status < 0 || status == NVME_SC_HOST_PATH_ERROR)
                return status;
 
        /*