nvme: add uevent variables for controller devices

When we send uevents to userspace, add controller specific
environment variables to uniquly identify the controller beyond
its device name.

This will be useful to address discovery log change events by
actually verifying that the discovery controller is indeed the
same as the device that generated the event.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 573e72139331244a88c7539f57cee31817da70c5..7d4e0c6f6d49048ab295ec4a32145a858a9eed48 100644 (file)
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -3635,6 +3635,33 @@ void nvme_remove_namespaces(struct nvme_ctrl *ctrl)
 }
 EXPORT_SYMBOL_GPL(nvme_remove_namespaces);
 
+static int nvme_class_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+       struct nvme_ctrl *ctrl =
+               container_of(dev, struct nvme_ctrl, ctrl_device);
+       struct nvmf_ctrl_options *opts = ctrl->opts;
+       int ret;
+
+       ret = add_uevent_var(env, "NVME_TRTYPE=%s", ctrl->ops->name);
+       if (ret)
+               return ret;
+
+       if (opts) {
+               ret = add_uevent_var(env, "NVME_TRADDR=%s", opts->traddr);
+               if (ret)
+                       return ret;
+
+               ret = add_uevent_var(env, "NVME_TRSVCID=%s",
+                               opts->trsvcid ?: "none");
+               if (ret)
+                       return ret;
+
+               ret = add_uevent_var(env, "NVME_HOST_TRADDR=%s",
+                               opts->host_traddr ?: "none");
+       }
+       return ret;
+}
+
 static void nvme_aen_uevent(struct nvme_ctrl *ctrl)
 {
        char *envp[2] = { NULL, NULL };
@@ -4073,6 +4100,7 @@ static int __init nvme_core_init(void)
                result = PTR_ERR(nvme_class);
                goto unregister_chrdev;
        }
+       nvme_class->dev_uevent = nvme_class_uevent;
 
        nvme_subsys_class = class_create(THIS_MODULE, "nvme-subsystem");
        if (IS_ERR(nvme_subsys_class)) {