[PATCH v5 6/9] nvmet: add uuid field to nvme_ns and populate via configfs

[Johannes Thumshirn]

Add the UUID field from the NVMe Namespace Identification Descriptor
to the nvmet_ns structure and allow it's population via configfs.

Signed-off-by: Johannes Thumshirn <jthumsh...@suse.de>
Reviewed-by: Max Gurtovoy <m...@mellanox.com>
Reviewed-by: Sagi Grimberg <s...@grimberg.me>
Reviewed-by: Hannes Reinecke <h...@suse.com>
---
 drivers/nvme/target/configfs.c | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/drivers/nvme/target/configfs.c b/drivers/nvme/target/configfs.c
index be8c800078e2..83bfe28fe7da 100644
--- a/drivers/nvme/target/configfs.c
+++ b/drivers/nvme/target/configfs.c
@@ -305,11 +305,41 @@ static ssize_t nvmet_ns_device_path_store(struct 
config_item *item,
 
 CONFIGFS_ATTR(nvmet_ns_, device_path);
 
+static ssize_t nvmet_ns_device_uuid_show(struct config_item *item, char *page)
+{
+       return sprintf(page, "%pUb\n", &to_nvmet_ns(item)->uuid);
+}
+
+static ssize_t nvmet_ns_device_uuid_store(struct config_item *item,
+                                         const char *page, size_t count)
+{
+       struct nvmet_ns *ns = to_nvmet_ns(item);
+       struct nvmet_subsys *subsys = ns->subsys;
+       int ret = 0;
+
+
+       mutex_lock(&subsys->lock);
+       if (ns->enabled) {
+               ret = -EBUSY;
+               goto out_unlock;
+       }
+
+
+       if (uuid_parse(page, &ns->uuid))
+               ret = -EINVAL;
+
+out_unlock:
+       mutex_unlock(&subsys->lock);
+       return ret ? ret : count;
+}
+
 static ssize_t nvmet_ns_device_nguid_show(struct config_item *item, char *page)
 {
        return sprintf(page, "%pUb\n", &to_nvmet_ns(item)->nguid);
 }
 
+CONFIGFS_ATTR(nvmet_ns_, device_uuid);
+
 static ssize_t nvmet_ns_device_nguid_store(struct config_item *item,
                const char *page, size_t count)
 {
@@ -379,6 +409,7 @@ CONFIGFS_ATTR(nvmet_ns_, enable);
 static struct configfs_attribute *nvmet_ns_attrs[] = {
        &nvmet_ns_attr_device_path,
        &nvmet_ns_attr_device_nguid,
+       &nvmet_ns_attr_device_uuid,
        &nvmet_ns_attr_enable,
        NULL,
 };
-- 
2.12.3