From: Hannes Reinecke <hare@suse.de>
Date: Wed, 22 Sep 2021 08:35:19 +0200
Subject: nvmet: make discovery NQN configurable
Git-commit: 626851e9225df93eda00f6b256cb74ad0860e418
Patch-mainline: v5.16-rc1
References: bsc#1192761
TPAR8013 allows for unique discovery NQNs, so make the discovery
controller NQN configurable by exposing a subsys attribute
'discovery_nqn'.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Hannes Reinecke <hare@suse.com>
---
drivers/nvme/target/configfs.c | 39 ++++++++++++++++++++++++++++++++++
drivers/nvme/target/core.c | 3 ++-
2 files changed, 41 insertions(+), 1 deletion(-)
diff --git a/drivers/nvme/target/configfs.c b/drivers/nvme/target/configfs.c
index 496d775c6770..091a0ca16361 100644
--- a/drivers/nvme/target/configfs.c
+++ b/drivers/nvme/target/configfs.c
@@ -1233,6 +1233,44 @@ 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)
@@ -1262,6 +1300,7 @@ 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
diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
index 93107af3310d..e1f41436ea2c 100644
--- a/drivers/nvme/target/core.c
+++ b/drivers/nvme/target/core.c
@@ -1493,7 +1493,8 @@ static struct nvmet_subsys *nvmet_find_get_subsys(struct nvmet_port *port,
if (!port)
return NULL;
- if (!strcmp(NVME_DISC_SUBSYS_NAME, subsysnqn)) {
+ if (!strcmp(NVME_DISC_SUBSYS_NAME, subsysnqn) ||
+ !strcmp(nvmet_disc_subsys->subsysnqn, subsysnqn)) {
if (!kref_get_unless_zero(&nvmet_disc_subsys->ref))
return NULL;
return nvmet_disc_subsys;
--
2.29.2