1 files changed, 76 insertions, 5 deletions

diff --git a/drivers/nvme/target/configfs.c b/drivers/nvme/target/configfs.c
index 77a6e817b315..7c43a0ad6877 100644
--- a/drivers/nvme/target/configfs.c
+++ b/drivers/nvme/target/configfs.c
@@ -754,6 +754,18 @@ static struct configfs_attribute *nvmet_ns_attrs[] = {
 	NULL,
 };
 
+bool nvmet_subsys_nsid_exists(struct nvmet_subsys *subsys, u32 nsid)
+{
+	struct config_item *ns_item;
+	char name[12];
+
+	snprintf(name, sizeof(name), "%u", nsid);
+	mutex_lock(&subsys->namespaces_group.cg_subsys->su_mutex);
+	ns_item = config_group_find_item(&subsys->namespaces_group, name);
+	mutex_unlock(&subsys->namespaces_group.cg_subsys->su_mutex);
+	return ns_item != NULL;
+}
+
 static void nvmet_ns_release(struct config_item *item)
 {
 	struct nvmet_ns *ns = to_nvmet_ns(item);
@@ -1613,6 +1625,11 @@ static struct config_group *nvmet_subsys_make(struct config_group *group,
 		return ERR_PTR(-EINVAL);
 	}
 
+	if (sysfs_streq(name, nvmet_disc_subsys->subsysnqn)) {
+		pr_err("can't create subsystem using unique discovery NQN\n");
+		return ERR_PTR(-EINVAL);
+	}
+
 	subsys = nvmet_subsys_alloc(name, NVME_NQN_NVME);
 	if (IS_ERR(subsys))
 		return ERR_CAST(subsys);
@@ -1990,11 +2007,17 @@ static struct config_group nvmet_ports_group;
 static ssize_t nvmet_host_dhchap_key_show(struct config_item *item,
 		char *page)
 {
-	u8 *dhchap_secret = to_host(item)->dhchap_secret;
+	u8 *dhchap_secret;
+	ssize_t ret;
 
+	down_read(&nvmet_config_sem);
+	dhchap_secret = to_host(item)->dhchap_secret;
 	if (!dhchap_secret)
-		return sprintf(page, "\n");
-	return sprintf(page, "%s\n", dhchap_secret);
+		ret = sprintf(page, "\n");
+	else
+		ret = sprintf(page, "%s\n", dhchap_secret);
+	up_read(&nvmet_config_sem);
+	return ret;
 }
 
 static ssize_t nvmet_host_dhchap_key_store(struct config_item *item,
@@ -2018,10 +2041,16 @@ static ssize_t nvmet_host_dhchap_ctrl_key_show(struct config_item *item,
 		char *page)
 {
 	u8 *dhchap_secret = to_host(item)->dhchap_ctrl_secret;
+	ssize_t ret;
 
+	down_read(&nvmet_config_sem);
+	dhchap_secret = to_host(item)->dhchap_ctrl_secret;
 	if (!dhchap_secret)
-		return sprintf(page, "\n");
-	return sprintf(page, "%s\n", dhchap_secret);
+		ret = sprintf(page, "\n");
+	else
+		ret = sprintf(page, "%s\n", dhchap_secret);
+	up_read(&nvmet_config_sem);
+	return ret;
 }
 
 static ssize_t nvmet_host_dhchap_ctrl_key_store(struct config_item *item,
@@ -2159,7 +2188,49 @@ static const struct config_item_type nvmet_hosts_type = {
 
 static struct config_group nvmet_hosts_group;
 
+static ssize_t nvmet_root_discovery_nqn_show(struct config_item *item,
+					     char *page)
+{
+	return snprintf(page, PAGE_SIZE, "%s\n", nvmet_disc_subsys->subsysnqn);
+}
+
+static ssize_t nvmet_root_discovery_nqn_store(struct config_item *item,
+		const char *page, size_t count)
+{
+	struct list_head *entry;
+	size_t len;
+
+	len = strcspn(page, "\n");
+	if (!len || len > NVMF_NQN_FIELD_LEN - 1)
+		return -EINVAL;
+
+	down_write(&nvmet_config_sem);
+	list_for_each(entry, &nvmet_subsystems_group.cg_children) {
+		struct config_item *item =
+			container_of(entry, struct config_item, ci_entry);
+
+		if (!strncmp(config_item_name(item), page, len)) {
+			pr_err("duplicate NQN %s\n", config_item_name(item));
+			up_write(&nvmet_config_sem);
+			return -EINVAL;
+		}
+	}
+	memset(nvmet_disc_subsys->subsysnqn, 0, NVMF_NQN_FIELD_LEN);
+	memcpy(nvmet_disc_subsys->subsysnqn, page, len);
+	up_write(&nvmet_config_sem);
+
+	return len;
+}
+
+CONFIGFS_ATTR(nvmet_root_, discovery_nqn);
+
+static struct configfs_attribute *nvmet_root_attrs[] = {
+	&nvmet_root_attr_discovery_nqn,
+	NULL,
+};
+
 static const struct config_item_type nvmet_root_type = {
+	.ct_attrs		= nvmet_root_attrs,
 	.ct_owner		= THIS_MODULE,
 };