nvme: rename uuid to nguid in nvme_ns

The uuid field in the nvme_ns structure represents the nguid field
from the identify namespace command. And as NVMe 1.3 introduced an
UUID in the NVMe Namespace Identification Descriptor this will
collide.

So rename the uuid to nguid to prevent any further
confusion. Unfortunately we export the nguid to sysfs in the uuid
sysfs attribute, but this can't be changed anymore without possibly
breaking existing userspace.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 0f397a1..c6e01ee 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -1011,7 +1011,7 @@
 	if (ns->ctrl->vs >= NVME_VS(1, 1, 0))
 		memcpy(ns->eui, (*id)->eui64, sizeof(ns->eui));
 	if (ns->ctrl->vs >= NVME_VS(1, 2, 0))
-		memcpy(ns->uuid, (*id)->nguid, sizeof(ns->uuid));
+		memcpy(ns->nguid, (*id)->nguid, sizeof(ns->nguid));
 
 	return 0;
 }
@@ -1784,8 +1784,8 @@
 	int serial_len = sizeof(ctrl->serial);
 	int model_len = sizeof(ctrl->model);
 
-	if (memchr_inv(ns->uuid, 0, sizeof(ns->uuid)))
-		return sprintf(buf, "eui.%16phN\n", ns->uuid);
+	if (memchr_inv(ns->nguid, 0, sizeof(ns->nguid)))
+		return sprintf(buf, "eui.%16phN\n", ns->nguid);
 
 	if (memchr_inv(ns->eui, 0, sizeof(ns->eui)))
 		return sprintf(buf, "eui.%8phN\n", ns->eui);
@@ -1804,7 +1804,7 @@
 								char *buf)
 {
 	struct nvme_ns *ns = nvme_get_ns_from_dev(dev);
-	return sprintf(buf, "%pU\n", ns->uuid);
+	return sprintf(buf, "%pU\n", ns->nguid);
 }
 static DEVICE_ATTR(uuid, S_IRUGO, uuid_show, NULL);
 
@@ -1839,7 +1839,7 @@
 	struct nvme_ns *ns = nvme_get_ns_from_dev(dev);
 
 	if (a == &dev_attr_uuid.attr) {
-		if (!memchr_inv(ns->uuid, 0, sizeof(ns->uuid)))
+		if (!memchr_inv(ns->nguid, 0, sizeof(ns->nguid)))
 			return 0;
 	}
 	if (a == &dev_attr_eui.attr) {