nvmet: revert "nvmet: make discovery NQN configurable"

Revert commit 626851e ("nvmet: make discovery NQN configurable");
the interface was deemed incorrect and will be replaced with a different
one.

Fixes: 626851e ("nvmet: make discovery NQN configurable")
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/target/configfs.c

@@ -1233,44 +1233,6 @@ static ssize_t nvmet_subsys_attr_model_store(struct config_item *item,
 }
 CONFIGFS_ATTR(nvmet_subsys_, attr_model);
 
-static ssize_t nvmet_subsys_attr_discovery_nqn_show(struct config_item *item,
-			char *page)
-{
-	return snprintf(page, PAGE_SIZE, "%s\n",
-			nvmet_disc_subsys->subsysnqn);
-}
-
-static ssize_t nvmet_subsys_attr_discovery_nqn_store(struct config_item *item,
-			const char *page, size_t count)
-{
-	struct nvmet_subsys *subsys = to_subsys(item);
-	char *subsysnqn;
-	int len;
-
-	len = strcspn(page, "\n");
-	if (!len)
-		return -EINVAL;
-
-	subsysnqn = kmemdup_nul(page, len, GFP_KERNEL);
-	if (!subsysnqn)
-		return -ENOMEM;
-
-	/*
-	 * The discovery NQN must be different from subsystem NQN.
-	 */
-	if (!strcmp(subsysnqn, subsys->subsysnqn)) {
-		kfree(subsysnqn);
-		return -EBUSY;
-	}
-	down_write(&nvmet_config_sem);
-	kfree(nvmet_disc_subsys->subsysnqn);
-	nvmet_disc_subsys->subsysnqn = subsysnqn;
-	up_write(&nvmet_config_sem);
-
-	return count;
-}
-CONFIGFS_ATTR(nvmet_subsys_, attr_discovery_nqn);
-
 #ifdef CONFIG_BLK_DEV_INTEGRITY
 static ssize_t nvmet_subsys_attr_pi_enable_show(struct config_item *item,
 						char *page)
@@ -1300,7 +1262,6 @@ static struct configfs_attribute *nvmet_subsys_attrs[] = {
 	&nvmet_subsys_attr_attr_cntlid_min,
 	&nvmet_subsys_attr_attr_cntlid_max,
 	&nvmet_subsys_attr_attr_model,
-	&nvmet_subsys_attr_attr_discovery_nqn,
 #ifdef CONFIG_BLK_DEV_INTEGRITY
 	&nvmet_subsys_attr_attr_pi_enable,
 #endif

drivers/nvme/target/core.c

@@ -1493,8 +1493,7 @@ static struct nvmet_subsys *nvmet_find_get_subsys(struct nvmet_port *port,
 	if (!port)
 		return NULL;
 
-	if (!strcmp(NVME_DISC_SUBSYS_NAME, subsysnqn) ||
-	    !strcmp(nvmet_disc_subsys->subsysnqn, subsysnqn)) {
+	if (!strcmp(NVME_DISC_SUBSYS_NAME, subsysnqn)) {
 		if (!kref_get_unless_zero(&nvmet_disc_subsys->ref))
 			return NULL;
 		return nvmet_disc_subsys;