btrfs: fix BUG_ON in btrfs_init_new_device()

Instead of BUG_ON return error to the caller. And handle the fail
condition by calling the abort transaction and going through the
error path.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 0be58b5..911bee9 100644 (file)
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -2394,7 +2394,10 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
        if (seeding_dev) {
                sb->s_flags &= ~MS_RDONLY;
                ret = btrfs_prepare_sprout(fs_info);
-               BUG_ON(ret); /* -ENOMEM */
+               if (ret) {
+                       btrfs_abort_transaction(trans, ret);
+                       goto error_trans;
+               }
        }
 
        device->fs_devices = fs_info->fs_devices;
@@ -2440,14 +2443,14 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
                mutex_unlock(&fs_info->chunk_mutex);
                if (ret) {
                        btrfs_abort_transaction(trans, ret);
-                       goto error_trans;
+                       goto error_sysfs;
                }
        }
 
        ret = btrfs_add_device(trans, fs_info, device);
        if (ret) {
                btrfs_abort_transaction(trans, ret);
-               goto error_trans;
+               goto error_sysfs;
        }
 
        if (seeding_dev) {
@@ -2456,7 +2459,7 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
                ret = btrfs_finish_sprout(trans, fs_info);
                if (ret) {
                        btrfs_abort_transaction(trans, ret);
-                       goto error_trans;
+                       goto error_sysfs;
                }
 
                /* Sprouting would change fsid of the mounted root,
@@ -2495,12 +2498,13 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
        update_dev_time(device_path);
        return ret;
 
+error_sysfs:
+       btrfs_sysfs_rm_device_link(fs_info->fs_devices, device);
 error_trans:
        if (seeding_dev)
                sb->s_flags |= MS_RDONLY;
        btrfs_end_transaction(trans);
        rcu_string_free(device->name);
-       btrfs_sysfs_rm_device_link(fs_info->fs_devices, device);
        kfree(device);
 error:
        blkdev_put(bdev, FMODE_EXCL);