From: Roland Dreier <roland@purestorage.com>
Date: Mon, 5 Mar 2018 11:59:53 -0800
Subject: [PATCH] nvme-fabrics: Ignore nr_io_queues option for discovery
 controllers
References: bsc#1102633
Git-commit: 0475821e229cfd9954b7501113d1acbc57b68689
Patch-mainline: v4.16-rc5

This removes a dependency on the order options are passed when creating
a fabrics controller.  With the old code, if "nr_io_queues" appears before
an "nqn" option specifying the discovery controller, then nr_io_queues
is overridden with zero.  If "nr_io_queues" appears after specifying the
discovery controller, then the nr_io_queues option is used to set the
number of queues, and the driver attempts to establish IO connections
to the discovery controller (which doesn't work).

It seems better to ignore (and warn about) the "nr_io_queues" option
if userspace has already asked to connect to the discovery controller.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Reviewed-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
 drivers/nvme/host/fabrics.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/nvme/host/fabrics.c b/drivers/nvme/host/fabrics.c
index 3dc0980d7435..34f363dc7de8 100644
--- a/drivers/nvme/host/fabrics.c
+++ b/drivers/nvme/host/fabrics.c
@@ -715,6 +715,11 @@ static int nvmf_parse_options(struct nvmf_ctrl_options *opts,
 				ret = -EINVAL;
 				goto out;
 			}
+			if (opts->discovery_nqn) {
+				pr_debug("Ignoring nr_io_queues value for discovery controller\n");
+				break;
+			}
+
 			opts->nr_io_queues = min_t(unsigned int,
 					num_online_cpus(), token);
 			break;
-- 
2.12.3