Btrfs: fix tracking of orphan inode count

In inode.c:btrfs_orphan_add() if we failed to insert the orphan
item, we would return without decrementing the orphan count that
we just incremented before attempting the insertion, leaving the
orphan inode count wrong.

In inode.c:btrfs_orphan_del(), we were decrementing the inode
orphan count if the bit BTRFS_INODE_ORPHAN_META_RESERVED was set,
which is logically wrong because it should be decremented if the
bit BTRFS_INODE_HAS_ORPHAN_ITEM was set - after all we increment
the count when we set the bit BTRFS_INODE_HAS_ORPHAN_ITEM elsewhere.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

fs/btrfs/inode.c

@@ -2969,6 +2969,7 @@ int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode)
 	if (insert >= 1) {
 		ret = btrfs_insert_orphan_item(trans, root, btrfs_ino(inode));
 		if (ret) {
+			atomic_dec(&root->orphan_inodes);
 			if (reserve) {
 				clear_bit(BTRFS_INODE_ORPHAN_META_RESERVED,
 					  &BTRFS_I(inode)->runtime_flags);
@@ -3018,14 +3019,16 @@ static int btrfs_orphan_del(struct btrfs_trans_handle *trans,
 		release_rsv = 1;
 	spin_unlock(&root->orphan_lock);
 
-	if (trans && delete_item)
-		ret = btrfs_del_orphan_item(trans, root, btrfs_ino(inode));
-
-	if (release_rsv) {
-		btrfs_orphan_release_metadata(inode);
+	if (delete_item) {
 		atomic_dec(&root->orphan_inodes);
+		if (trans)
+			ret = btrfs_del_orphan_item(trans, root,
+						    btrfs_ino(inode));
 	}
 
+	if (release_rsv)
+		btrfs_orphan_release_metadata(inode);
+
 	return ret;
 }