dm: add add_disk() error handling

We never checked for errors on add_disk() as this function returned
void. Now that this is fixed, use the shiny new error handling.

There are two calls to dm_setup_md_queue() which can fail then, one on
dm_early_create() and we can easily see that the error path there
calls dm_destroy in the error path. The other use case is on the ioctl
table_load case. If that fails userspace needs to call the
DM_DEV_REMOVE_CMD to cleanup the state - similar to any other
failure.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 76d9da4..b966634 100644 (file)
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -2086,7 +2086,9 @@ int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t)
        if (r)
                return r;
 
-       add_disk(md->disk);
+       r = add_disk(md->disk);
+       if (r)
+               return r;
 
        r = dm_sysfs_init(md);
        if (r) {