xfs: remove parent pointers in unlink

This patch removes the parent pointer attribute during unlink
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
[djwong: adjust to new ondisk format, minor rebase fixes]
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

fs/xfs/libxfs/xfs_parent.c

@@ -205,3 +205,25 @@ xfs_parent_addname(
 	xfs_attr_defer_add(&ppargs->args, XFS_ATTR_DEFER_SET);
 	return 0;
 }
+
+/* Remove a parent pointer to reflect a dirent removal. */
+int
+xfs_parent_removename(
+	struct xfs_trans	*tp,
+	struct xfs_parent_args	*ppargs,
+	struct xfs_inode	*dp,
+	const struct xfs_name	*parent_name,
+	struct xfs_inode	*child)
+{
+	int			error;
+
+	error = xfs_parent_iread_extents(tp, child);
+	if (error)
+		return error;
+
+	xfs_inode_to_parent_rec(&ppargs->rec, dp);
+	xfs_parent_da_args_init(&ppargs->args, tp, &ppargs->rec, child,
+			child->i_ino, parent_name);
+	xfs_attr_defer_add(&ppargs->args, XFS_ATTR_DEFER_REMOVE);
+	return 0;
+}

fs/xfs/libxfs/xfs_parent.h

@@ -81,5 +81,8 @@ xfs_parent_finish(
 int xfs_parent_addname(struct xfs_trans *tp, struct xfs_parent_args *ppargs,
 		struct xfs_inode *dp, const struct xfs_name *parent_name,
 		struct xfs_inode *child);
+int xfs_parent_removename(struct xfs_trans *tp, struct xfs_parent_args *ppargs,
+		struct xfs_inode *dp, const struct xfs_name *parent_name,
+		struct xfs_inode *child);
 
 #endif /* __XFS_PARENT_H__ */

fs/xfs/libxfs/xfs_trans_space.c

@@ -81,3 +81,16 @@ xfs_symlink_space_res(
 
 	return ret;
 }
+
+unsigned int
+xfs_remove_space_res(
+	struct xfs_mount	*mp,
+	unsigned int		namelen)
+{
+	unsigned int		ret = XFS_DIRREMOVE_SPACE_RES(mp);
+
+	if (xfs_has_parent(mp))
+		ret += xfs_parent_calc_space_res(mp, namelen);
+
+	return ret;
+}

fs/xfs/libxfs/xfs_trans_space.h

@@ -91,8 +91,6 @@
 	 XFS_DQUOT_CLUSTER_SIZE_FSB)
 #define	XFS_QM_QINOCREATE_SPACE_RES(mp)	\
 	XFS_IALLOC_SPACE_RES(mp)
-#define	XFS_REMOVE_SPACE_RES(mp)	\
-	XFS_DIRREMOVE_SPACE_RES(mp)
 #define	XFS_RENAME_SPACE_RES(mp,nl)	\
 	(XFS_DIRREMOVE_SPACE_RES(mp) + XFS_DIRENTER_SPACE_RES(mp,nl))
 #define XFS_IFREE_SPACE_RES(mp)		\
@@ -106,5 +104,6 @@ unsigned int xfs_mkdir_space_res(struct xfs_mount *mp, unsigned int namelen);
 unsigned int xfs_link_space_res(struct xfs_mount *mp, unsigned int namelen);
 unsigned int xfs_symlink_space_res(struct xfs_mount *mp, unsigned int namelen,
 		unsigned int fsblocks);
+unsigned int xfs_remove_space_res(struct xfs_mount *mp, unsigned int namelen);
 
 #endif	/* __XFS_TRANS_SPACE_H__ */

fs/xfs/xfs_inode.c

@@ -2721,16 +2721,17 @@ xfs_iunpin_wait(
  */
 int
 xfs_remove(
-	xfs_inode_t             *dp,
+	struct xfs_inode	*dp,
 	struct xfs_name		*name,
-	xfs_inode_t		*ip)
+	struct xfs_inode	*ip)
 {
-	xfs_mount_t		*mp = dp->i_mount;
-	xfs_trans_t             *tp = NULL;
+	struct xfs_mount	*mp = dp->i_mount;
+	struct xfs_trans	*tp = NULL;
 	int			is_dir = S_ISDIR(VFS_I(ip)->i_mode);
 	int			dontcare;
 	int                     error = 0;
 	uint			resblks;
+	struct xfs_parent_args	*ppargs;
 
 	trace_xfs_remove(dp, name);
 
@@ -2747,6 +2748,10 @@ xfs_remove(
 	if (error)
 		goto std_return;
 
+	error = xfs_parent_start(mp, &ppargs);
+	if (error)
+		goto std_return;
+
 	/*
 	 * We try to get the real space reservation first, allowing for
 	 * directory btree deletion(s) implying possible bmap insert(s).  If we
@@ -2758,12 +2763,12 @@ xfs_remove(
 	 * the directory code can handle a reservationless update and we don't
 	 * want to prevent a user from trying to free space by deleting things.
 	 */
-	resblks = XFS_REMOVE_SPACE_RES(mp);
+	resblks = xfs_remove_space_res(mp, name->len);
 	error = xfs_trans_alloc_dir(dp, &M_RES(mp)->tr_remove, ip, &resblks,
 			&tp, &dontcare);
 	if (error) {
 		ASSERT(error != -ENOSPC);
-		goto std_return;
+		goto out_parent;
 	}
 
 	/*
@@ -2823,6 +2828,13 @@ xfs_remove(
 		goto out_trans_cancel;
 	}
 
+	/* Remove parent pointer. */
+	if (ppargs) {
+		error = xfs_parent_removename(tp, ppargs, dp, name, ip);
+		if (error)
+			goto out_trans_cancel;
+	}
+
 	/*
 	 * Drop the link from dp to ip, and if ip was a directory, remove the
 	 * '.' and '..' references since we freed the directory.
@@ -2846,6 +2858,7 @@ xfs_remove(
 
 	xfs_iunlock(ip, XFS_ILOCK_EXCL);
 	xfs_iunlock(dp, XFS_ILOCK_EXCL);
+	xfs_parent_finish(mp, ppargs);
 	return 0;
 
  out_trans_cancel:
@@ -2853,6 +2866,8 @@ xfs_remove(
  out_unlock:
 	xfs_iunlock(ip, XFS_ILOCK_EXCL);
 	xfs_iunlock(dp, XFS_ILOCK_EXCL);
+ out_parent:
+	xfs_parent_finish(mp, ppargs);
  std_return:
 	return error;
 }