rbd: defer setting device id

Hold off setting the device id and formatting the device name
in rbd_add() until just before it's needed.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index aa4752d9d9fab15c9b5ab226137bb6b203bbf7cd..7a600ca2dbcf497a5ac9e2c3322c477ea28917bf 100644 (file)
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -2554,10 +2554,10 @@ static ssize_t rbd_add(struct bus_type *bus,
 
        options = kmalloc(count, GFP_KERNEL);
        if (!options)
-               goto err_nomem;
+               goto err_out_mem;
        rbd_dev = kzalloc(sizeof(*rbd_dev), GFP_KERNEL);
        if (!rbd_dev)
-               goto err_nomem;
+               goto err_out_mem;
 
        /* static rbd_device initialization */
        spin_lock_init(&rbd_dev->lock);
@@ -2565,25 +2565,17 @@ static ssize_t rbd_add(struct bus_type *bus,
        INIT_LIST_HEAD(&rbd_dev->snaps);
        init_rwsem(&rbd_dev->header_rwsem);
 
-       /* generate unique id: find highest unique id, add one */
-       rbd_dev_id_get(rbd_dev);
-
-       /* Fill in the device name, now that we have its id. */
-       BUILD_BUG_ON(DEV_NAME_LEN
-                       < sizeof (RBD_DRV_NAME) + MAX_INT_FORMAT_WIDTH);
-       sprintf(rbd_dev->name, "%s%d", RBD_DRV_NAME, rbd_dev->dev_id);
-
        /* parse add command */
        snap_name = rbd_add_parse_args(rbd_dev, buf,
                                &mon_addrs, &mon_addrs_size, options, count);
        if (IS_ERR(snap_name)) {
                rc = PTR_ERR(snap_name);
-               goto err_put_id;
+               goto err_out_mem;
        }
 
        rc = rbd_get_client(rbd_dev, mon_addrs, mon_addrs_size - 1, options);
        if (rc < 0)
-               goto err_put_id;
+               goto err_out_args;
 
        /* pick the pool */
        osdc = &rbd_dev->rbd_client->client->osdc;
@@ -2616,10 +2608,19 @@ static ssize_t rbd_add(struct bus_type *bus,
        if (rc)
                goto err_out_header;
 
-       /* register our block device */
+       /* generate unique id: find highest unique id, add one */
+       rbd_dev_id_get(rbd_dev);
+
+       /* Fill in the device name, now that we have its id. */
+       BUILD_BUG_ON(DEV_NAME_LEN
+                       < sizeof (RBD_DRV_NAME) + MAX_INT_FORMAT_WIDTH);
+       sprintf(rbd_dev->name, "%s%d", RBD_DRV_NAME, rbd_dev->dev_id);
+
+       /* Get our block major device number. */
+
        rc = register_blkdev(0, rbd_dev->name);
        if (rc < 0)
-               goto err_out_header;
+               goto err_out_id;
        rbd_dev->major = rc;
 
        rc = rbd_bus_add_dev(rbd_dev);
@@ -2665,19 +2666,18 @@ err_out_bus:
 
 err_out_blkdev:
        unregister_blkdev(rbd_dev->major, rbd_dev->name);
+err_out_id:
+       rbd_dev_id_put(rbd_dev);
 err_out_header:
        rbd_header_free(&rbd_dev->header);
 err_out_client:
        kfree(rbd_dev->header_name);
        rbd_put_client(rbd_dev);
-err_put_id:
-       if (rbd_dev->pool_name) {
-               kfree(rbd_dev->mapping.snap_name);
-               kfree(rbd_dev->image_name);
-               kfree(rbd_dev->pool_name);
-       }
-       rbd_dev_id_put(rbd_dev);
-err_nomem:
+err_out_args:
+       kfree(rbd_dev->mapping.snap_name);
+       kfree(rbd_dev->image_name);
+       kfree(rbd_dev->pool_name);
+err_out_mem:
        kfree(rbd_dev);
        kfree(options);