nvme: also provide a UUID in the WWID sysfs attribute

The WWID sysfs attribute can provide multiple means of a World Wide ID
for a NVMe device. It can either be a NGUID, a EUI-64 or a concatenation
of VID, Serial Number, Model and the Namespace ID in this order of
preference.

If the target also sends us a UUID use the UUID for identification and
give it the highest priority.

This eases generation of /dev/disk/by-* symlinks.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Johannes Thumshirn 2017-07-12 15:38:56 +02:00 committed by Christoph Hellwig
parent 76451d79bd
commit 6484f5d16f

View File

@ -1995,6 +1995,9 @@ static ssize_t wwid_show(struct device *dev, struct device_attribute *attr,
int serial_len = sizeof(ctrl->serial);
int model_len = sizeof(ctrl->model);
if (!uuid_is_null(&ns->uuid))
return sprintf(buf, "uuid.%pU\n", &ns->uuid);
if (memchr_inv(ns->nguid, 0, sizeof(ns->nguid)))
return sprintf(buf, "eui.%16phN\n", ns->nguid);