nvme/multipath: Fix multipath disabled naming collisions

When CONFIG_NVME_MULTIPATH is set, but we're not using nvme to multipath,
namespaces with multiple paths were not creating unique names due to
reusing the same instance number from the namespace's head.

This patch fixes this by falling back to the non-multipath naming method
when the parameter disabled using multipath.

Reported-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 127a9cbf3314458548b28e1bc05a2a99408c2309..a3771c5729f542d6b27e15bc6f66f5ebb75a3372 100644 (file)
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -2998,31 +2998,7 @@ static void nvme_alloc_ns(struct nvme_ctrl *ctrl, unsigned nsid)
        if (nvme_init_ns_head(ns, nsid, id))
                goto out_free_id;
        nvme_setup_streams_ns(ctrl, ns);
-       
-#ifdef CONFIG_NVME_MULTIPATH
-       /*
-        * If multipathing is enabled we need to always use the subsystem
-        * instance number for numbering our devices to avoid conflicts
-        * between subsystems that have multiple controllers and thus use
-        * the multipath-aware subsystem node and those that have a single
-        * controller and use the controller node directly.
-        */
-       if (ns->head->disk) {
-               sprintf(disk_name, "nvme%dc%dn%d", ctrl->subsys->instance,
-                               ctrl->cntlid, ns->head->instance);
-               flags = GENHD_FL_HIDDEN;
-       } else {
-               sprintf(disk_name, "nvme%dn%d", ctrl->subsys->instance,
-                               ns->head->instance);
-       }
-#else
-       /*
-        * But without the multipath code enabled, multiple controller per
-        * subsystems are visible as devices and thus we cannot use the
-        * subsystem instance.
-        */
-       sprintf(disk_name, "nvme%dn%d", ctrl->instance, ns->head->instance);
-#endif
+       nvme_set_disk_name(disk_name, ns, ctrl, &flags);
 
        if ((ctrl->quirks & NVME_QUIRK_LIGHTNVM) && id->vs[0] == 0x1) {
                if (nvme_nvm_register(ns, disk_name, node)) {

diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c
index 3ded009e76313af9c2d7dcc531591a20affde0c7..d7b664ae5923e1217a493d68f1dac96c8a3cce4c 100644 (file)
--- a/drivers/nvme/host/multipath.c
+++ b/drivers/nvme/host/multipath.c
@@ -19,6 +19,28 @@ module_param(multipath, bool, 0444);
 MODULE_PARM_DESC(multipath,
        "turn on native support for multiple controllers per subsystem");
 
+/*
+ * If multipathing is enabled we need to always use the subsystem instance
+ * number for numbering our devices to avoid conflicts between subsystems that
+ * have multiple controllers and thus use the multipath-aware subsystem node
+ * and those that have a single controller and use the controller node
+ * directly.
+ */
+void nvme_set_disk_name(char *disk_name, struct nvme_ns *ns,
+                       struct nvme_ctrl *ctrl, int *flags)
+{
+       if (!multipath) {
+               sprintf(disk_name, "nvme%dn%d", ctrl->instance, ns->head->instance);
+       } else if (ns->head->disk) {
+               sprintf(disk_name, "nvme%dc%dn%d", ctrl->subsys->instance,
+                               ctrl->cntlid, ns->head->instance);
+               *flags = GENHD_FL_HIDDEN;
+       } else {
+               sprintf(disk_name, "nvme%dn%d", ctrl->subsys->instance,
+                               ns->head->instance);
+       }
+}
+
 void nvme_failover_req(struct request *req)
 {
        struct nvme_ns *ns = req->q->queuedata;

diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index 061fecfd44f59046ead7fdc40a9469da38ae47bd..7ded7a51c4301958e6d6d988593efe36a85a0a71 100644 (file)
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -436,6 +436,8 @@ extern const struct attribute_group nvme_ns_id_attr_group;
 extern const struct block_device_operations nvme_ns_head_ops;
 
 #ifdef CONFIG_NVME_MULTIPATH
+void nvme_set_disk_name(char *disk_name, struct nvme_ns *ns,
+                       struct nvme_ctrl *ctrl, int *flags);
 void nvme_failover_req(struct request *req);
 bool nvme_req_needs_failover(struct request *req, blk_status_t error);
 void nvme_kick_requeue_lists(struct nvme_ctrl *ctrl);
@@ -461,6 +463,16 @@ static inline void nvme_mpath_check_last_path(struct nvme_ns *ns)
 }
 
 #else
+/*
+ * Without the multipath code enabled, multiple controller per subsystems are
+ * visible as devices and thus we cannot use the subsystem instance.
+ */
+static inline void nvme_set_disk_name(char *disk_name, struct nvme_ns *ns,
+                                     struct nvme_ctrl *ctrl, int *flags)
+{
+       sprintf(disk_name, "nvme%dn%d", ctrl->instance, ns->head->instance);
+}
+
 static inline void nvme_failover_req(struct request *req)
 {
 }