[PATCH v16 04/11] xfs: Add helper xfs_attr_set_fmt

[Allison Henderson <allison.henderson@xxxxxxxxxx>]

This patch adds a helper function xfs_attr_set_fmt.  This will help
isolate the code that will require state management from the portions
that do not.  xfs_attr_set_fmt returns 0 when the attr has been set and
no further action is needed.  It returns -EAGAIN when shortform has been
transformed to leaf, and the calling function should proceed the set the
attr in leaf form.

Signed-off-by: Allison Henderson <allison.henderson@xxxxxxxxxx>
Reviewed-by: Brian Foster <bfoster@xxxxxxxxxx>

---
 fs/xfs/libxfs/xfs_attr.c | 79 ++++++++++++++++++++++++++++--------------------
 1 file changed, 46 insertions(+), 33 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
index 5216f67..d46324a 100644
--- a/fs/xfs/libxfs/xfs_attr.c
+++ b/fs/xfs/libxfs/xfs_attr.c
@@ -216,6 +216,48 @@ xfs_attr_is_shortform(
 		ip->i_afp->if_nextents == 0);
 }
 
+STATIC int
+xfs_attr_set_fmt(
+	struct xfs_da_args	*args)
+{
+	struct xfs_buf          *leaf_bp = NULL;
+	struct xfs_inode	*dp = args->dp;
+	int			error2, error = 0;
+
+	/*
+	 * Try to add the attr to the attribute list in the inode.
+	 */
+	error = xfs_attr_try_sf_addname(dp, args);
+	if (error != -ENOSPC) {
+		error2 = xfs_trans_commit(args->trans);
+		args->trans = NULL;
+		return error ? error : error2;
+	}
+
+	/*
+	 * It won't fit in the shortform, transform to a leaf block.
+	 * GROT: another possible req'mt for a double-split btree op.
+	 */
+	error = xfs_attr_shortform_to_leaf(args, &leaf_bp);
+	if (error)
+		return error;
+
+	/*
+	 * Prevent the leaf buffer from being unlocked so that a
+	 * concurrent AIL push cannot grab the half-baked leaf buffer
+	 * and run into problems with the write verifier.
+	 */
+	xfs_trans_bhold(args->trans, leaf_bp);
+	error = xfs_defer_finish(&args->trans);
+	xfs_trans_bhold_release(args->trans, leaf_bp);
+	if (error) {
+		xfs_trans_brelse(args->trans, leaf_bp);
+		return error;
+	}
+
+	return -EAGAIN;
+}
+
 /*
  * Set the attribute specified in @args.
  */
@@ -224,8 +266,7 @@ xfs_attr_set_args(
 	struct xfs_da_args	*args)
 {
 	struct xfs_inode	*dp = args->dp;
-	struct xfs_buf          *leaf_bp = NULL;
-	int			error2, error = 0;
+	int			error;
 
 	/*
 	 * If the attribute list is already in leaf format, jump straight to
@@ -234,36 +275,9 @@ xfs_attr_set_args(
 	 * again.
 	 */
 	if (xfs_attr_is_shortform(dp)) {
-		/*
-		 * Try to add the attr to the attribute list in the inode.
-		 */
-		error = xfs_attr_try_sf_addname(dp, args);
-		if (error != -ENOSPC) {
-			error2 = xfs_trans_commit(args->trans);
-			args->trans = NULL;
-			return error ? error : error2;
-		}
-
-		/*
-		 * It won't fit in the shortform, transform to a leaf block.
-		 * GROT: another possible req'mt for a double-split btree op.
-		 */
-		error = xfs_attr_shortform_to_leaf(args, &leaf_bp);
-		if (error)
-			return error;
-
-		/*
-		 * Prevent the leaf buffer from being unlocked so that a
-		 * concurrent AIL push cannot grab the half-baked leaf buffer
-		 * and run into problems with the write verifier.
-		 */
-		xfs_trans_bhold(args->trans, leaf_bp);
-		error = xfs_defer_finish(&args->trans);
-		xfs_trans_bhold_release(args->trans, leaf_bp);
-		if (error) {
-			xfs_trans_brelse(args->trans, leaf_bp);
+		error = xfs_attr_set_fmt(args);
+		if (error != -EAGAIN)
 			return error;
-		}
 	}
 
 	if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
@@ -297,8 +311,7 @@ xfs_attr_set_args(
 			return error;
 	}
 
-	error = xfs_attr_node_addname(args);
-	return error;
+	return xfs_attr_node_addname(args);
 }
 
 /*
-- 
2.7.4