btrfs: fix warning in iput for bad-inode

iput() shouldn't be called for inodes in I_NEW state.
We need to mark inode as constructed first.

WARNING: at fs/inode.c:1309 iput+0x20b/0x210()
Call Trace:
 [<ffffffff8103e7ba>] warn_slowpath_common+0x7a/0xb0
 [<ffffffff8103e805>] warn_slowpath_null+0x15/0x20
 [<ffffffff810eaf0b>] iput+0x20b/0x210
 [<ffffffff811b96fb>] btrfs_iget+0x1eb/0x4a0
 [<ffffffff811c3ad6>] btrfs_run_defrag_inodes+0x136/0x210
 [<ffffffff811ad55f>] cleaner_kthread+0x17f/0x1a0
 [<ffffffff81035b7d>] ? sub_preempt_count+0x9d/0xd0
 [<ffffffff811ad3e0>] ? transaction_kthread+0x280/0x280
 [<ffffffff8105af86>] kthread+0x96/0xa0
 [<ffffffff814336d4>] kernel_thread_helper+0x4/0x10
 [<ffffffff8105aef0>] ? kthread_worker_fn+0x190/0x190
 [<ffffffff814336d0>] ? gs_change+0xb/0xb

Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
CC: Konstantin Khlebnikov <khlebnikov@openvz.org>
Tested-by: David Sterba <dsterba@suse.cz>
CC: Josef Bacik <josef@redhat.com>
CC: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 3 insertions, 7 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 34195f9fc6bb..edd45f709989 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -3952,7 +3952,6 @@ struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
                          struct btrfs_root *root, int *new)
 {
         struct inode *inode;
-        int bad_inode = 0;
 
         inode = btrfs_iget_locked(s, location->objectid, root);
         if (!inode)
@@ -3968,15 +3967,12 @@ struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
                         if (new)
                                 *new = 1;
                 } else {
-                        bad_inode = 1;
+                        unlock_new_inode(inode);
+                        iput(inode);
+                        inode = ERR_PTR(-ESTALE);
                 }
         }
 
-        if (bad_inode) {
-                iput(inode);
-                inode = ERR_PTR(-ESTALE);
-        }
-
         return inode;
 }