nvme: Add connect option 'discovery'

Add a connect option 'discovery' to specify that the connection
should be made to a discovery controller, not a normal I/O controller.
With discovery controllers supporting unique subsystem NQNs we
cannot easily distinguish by the subsystem NQN if this should be
a discovery connection, but we need this information to blank out
options not supported by discovery controllers.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 0f0f64d..fd856ee 100644 (file)
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -2737,6 +2737,13 @@ static int nvme_init_subsystem(struct nvme_ctrl *ctrl, struct nvme_id_ctrl *id)
        else
                subsys->subtype = NVME_NQN_NVME;
 
+       if (nvme_discovery_ctrl(ctrl) && subsys->subtype != NVME_NQN_DISC) {
+               dev_err(ctrl->device,
+                       "Subsystem %s is not a discovery controller",
+                       subsys->subnqn);
+               kfree(subsys);
+               return -EINVAL;
+       }
        subsys->awupf = le16_to_cpu(id->awupf);
 #ifdef CONFIG_NVME_MULTIPATH
        subsys->iopolicy = NVME_IOPOLICY_NUMA;

diff --git a/drivers/nvme/host/fabrics.c b/drivers/nvme/host/fabrics.c
index 668c6bb..c5a2b71 100644 (file)
--- a/drivers/nvme/host/fabrics.c
+++ b/drivers/nvme/host/fabrics.c
@@ -548,6 +548,7 @@ static const match_table_t opt_tokens = {
        { NVMF_OPT_NR_POLL_QUEUES,      "nr_poll_queues=%d"     },
        { NVMF_OPT_TOS,                 "tos=%d"                },
        { NVMF_OPT_FAIL_FAST_TMO,       "fast_io_fail_tmo=%d"   },
+       { NVMF_OPT_DISCOVERY,           "discovery"             },
        { NVMF_OPT_ERR,                 NULL                    }
 };
 
@@ -823,6 +824,9 @@ static int nvmf_parse_options(struct nvmf_ctrl_options *opts,
                        }
                        opts->tos = token;
                        break;
+               case NVMF_OPT_DISCOVERY:
+                       opts->discovery_nqn = true;
+                       break;
                default:
                        pr_warn("unknown parameter or missing value '%s' in ctrl creation request\n",
                                p);
@@ -949,7 +953,7 @@ EXPORT_SYMBOL_GPL(nvmf_free_options);
 #define NVMF_ALLOWED_OPTS      (NVMF_OPT_QUEUE_SIZE | NVMF_OPT_NR_IO_QUEUES | \
                                 NVMF_OPT_KATO | NVMF_OPT_HOSTNQN | \
                                 NVMF_OPT_HOST_ID | NVMF_OPT_DUP_CONNECT |\
-                                NVMF_OPT_DISABLE_SQFLOW |\
+                                NVMF_OPT_DISABLE_SQFLOW | NVMF_OPT_DISCOVERY |\
                                 NVMF_OPT_FAIL_FAST_TMO)
 
 static struct nvme_ctrl *

diff --git a/drivers/nvme/host/fabrics.h b/drivers/nvme/host/fabrics.h
index a146cb9..b61b666 100644 (file)
--- a/drivers/nvme/host/fabrics.h
+++ b/drivers/nvme/host/fabrics.h
@@ -67,6 +67,7 @@ enum {
        NVMF_OPT_TOS            = 1 << 19,
        NVMF_OPT_FAIL_FAST_TMO  = 1 << 20,
        NVMF_OPT_HOST_IFACE     = 1 << 21,
+       NVMF_OPT_DISCOVERY      = 1 << 22,
 };
 
 /**