[RFC PATCH v2 2/4] btrfs: don't BUG_ON() in btrfs_link_subvol()

[Lu Fengqi]

Both of btrfs_update_inode() and btrfs_add_root_ref() may fail because
of ENOMEM. So there's no reason to panic here, we can replace BUG_ON()
with btrfs_abort_transaction() here.

Signed-off-by: Lu Fengqi <lufq.f...@cn.fujitsu.com>
---
 fs/btrfs/ioctl.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 1b03d07acde2..f6173d4e7ced 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -572,11 +572,17 @@ static int btrfs_link_subvol(struct btrfs_trans_handle 
*trans,
 
        btrfs_i_size_write(BTRFS_I(dir), dir->i_size + namelen * 2);
        ret = btrfs_update_inode(trans, root, dir);
-       BUG_ON(ret);
+       if (ret) {
+               btrfs_abort_transaction(trans, ret);
+               return ret;
+       }
 
        ret = btrfs_add_root_ref(trans, objectid, root->root_key.objectid,
                                 btrfs_ino(BTRFS_I(dir)), index, name, namelen);
-       BUG_ON(ret);
+       if (ret) {
+               btrfs_abort_transaction(trans, ret);
+               return ret;
+       }
 
        return ret;
 }
-- 
2.18.0