Messages in this thread Patch in this message | | | From | Johannes Thumshirn <> | Subject | [PATCH v2 6/8] nvme: provide UUID value to userspace | Date | Thu, 1 Jun 2017 13:17:48 +0200 |
| |
Now that we have a way for getting the UUID from a target, provide it to userspace as well.
Unfortunately there is already a sysfs attribute called UUID which is a misnomer as it holds the NGUID value. So instead of creating yet another wrong name, create a new 'nguid' sysfs attribute for the NGUID. For the UUID attribute add a check wheter the namespace has a UUID assigned to it and return this or return the NGUID to maintain backwards compatibility. This should give userspace a chance to catch up.
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> --- drivers/nvme/host/core.c | 25 ++++++++++++++++++++++++- 1 file changed, 24 insertions(+), 1 deletion(-)
diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 37047841da0e..3aa5b12680e5 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -1887,11 +1887,28 @@ static ssize_t wwid_show(struct device *dev, struct device_attribute *attr, } static DEVICE_ATTR(wwid, S_IRUGO, wwid_show, NULL); +static ssize_t nguid_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct nvme_ns *ns = nvme_get_ns_from_dev(dev); + return sprintf(buf, "%pU\n", ns->nguid); +} +static DEVICE_ATTR(nguid, S_IRUGO, nguid_show, NULL); + static ssize_t uuid_show(struct device *dev, struct device_attribute *attr, char *buf) { struct nvme_ns *ns = nvme_get_ns_from_dev(dev); - return sprintf(buf, "%pU\n", ns->nguid); + + /* For backward compatibility expose the NGUID to userspace if + * we have no UUID set + */ + if (!memchr_inv(ns->uuid, 0, sizeof(ns->uuid))) { + printk_ratelimited(KERN_WARNING + "No UUID available providing old NGUID\n"); + return sprintf(buf, "%pU\n", ns->nguid); + } + return sprintf(buf, "%pU\n", ns->uuid); } static DEVICE_ATTR(uuid, S_IRUGO, uuid_show, NULL); @@ -1914,6 +1931,7 @@ static DEVICE_ATTR(nsid, S_IRUGO, nsid_show, NULL); static struct attribute *nvme_ns_attrs[] = { &dev_attr_wwid.attr, &dev_attr_uuid.attr, + &dev_attr_nguid.attr, &dev_attr_eui.attr, &dev_attr_nsid.attr, NULL, @@ -1926,6 +1944,11 @@ static umode_t nvme_ns_attrs_are_visible(struct kobject *kobj, 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)) || + !memchr_inv(ns->nguid, 0, sizeof(ns->nguid))) + return 0; + } + if (a == &dev_attr_nguid.attr) { if (!memchr_inv(ns->nguid, 0, sizeof(ns->nguid))) return 0; } -- 2.12.0
| |