md: return -ENODEV if rdev has no mddev assigned

Mdadm expects that setting drive as faulty will fail with -EBUSY only if
this operation will cause RAID to be failed. If this happens, it will
try to stop the array. Currently -EBUSY might also be returned if rdev
is in the middle of the removal process - for example there is a race
with mdmon that already requested the drive to be failed/removed.

If rdev does not contain mddev, return -ENODEV instead, so the caller
can distinguish between those two cases and behave accordingly.

Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Pawel Baldysiak <pawel.baldysiak@intel.com>
Signed-off-by: Song Liu <songliubraving@fb.com>

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 5410153..45ffa23 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -3380,10 +3380,10 @@ rdev_attr_store(struct kobject *kobj, struct attribute *attr,
                return -EIO;
        if (!capable(CAP_SYS_ADMIN))
                return -EACCES;
-       rv = mddev ? mddev_lock(mddev): -EBUSY;
+       rv = mddev ? mddev_lock(mddev) : -ENODEV;
        if (!rv) {
                if (rdev->mddev == NULL)
-                       rv = -EBUSY;
+                       rv = -ENODEV;
                else
                        rv = entry->store(rdev, page, length);
                mddev_unlock(mddev);