rbd: supported_features bus attribute

... so that userspace can generate meaningful error messages and spell
out unsupported features that need to be disabled.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Sage Weil <sage@redhat.com>
This commit is contained in:
Ilya Dryomov 2017-03-02 19:56:57 +01:00
parent b581a5854e
commit 8767b293a4

View file

@ -120,10 +120,11 @@ static int atomic_dec_return_safe(atomic_t *v)
/* Feature bits */
#define RBD_FEATURE_LAYERING (1<<0)
#define RBD_FEATURE_STRIPINGV2 (1<<1)
#define RBD_FEATURE_EXCLUSIVE_LOCK (1<<2)
#define RBD_FEATURE_DATA_POOL (1<<7)
#define RBD_FEATURE_LAYERING (1ULL<<0)
#define RBD_FEATURE_STRIPINGV2 (1ULL<<1)
#define RBD_FEATURE_EXCLUSIVE_LOCK (1ULL<<2)
#define RBD_FEATURE_DATA_POOL (1ULL<<7)
#define RBD_FEATURES_ALL (RBD_FEATURE_LAYERING | \
RBD_FEATURE_STRIPINGV2 | \
RBD_FEATURE_EXCLUSIVE_LOCK | \
@ -499,16 +500,23 @@ static bool rbd_is_lock_owner(struct rbd_device *rbd_dev)
return is_lock_owner;
}
static ssize_t rbd_supported_features_show(struct bus_type *bus, char *buf)
{
return sprintf(buf, "0x%llx\n", RBD_FEATURES_SUPPORTED);
}
static BUS_ATTR(add, S_IWUSR, NULL, rbd_add);
static BUS_ATTR(remove, S_IWUSR, NULL, rbd_remove);
static BUS_ATTR(add_single_major, S_IWUSR, NULL, rbd_add_single_major);
static BUS_ATTR(remove_single_major, S_IWUSR, NULL, rbd_remove_single_major);
static BUS_ATTR(supported_features, S_IRUGO, rbd_supported_features_show, NULL);
static struct attribute *rbd_bus_attrs[] = {
&bus_attr_add.attr,
&bus_attr_remove.attr,
&bus_attr_add_single_major.attr,
&bus_attr_remove_single_major.attr,
&bus_attr_supported_features.attr,
NULL,
};