[PATCH v6 14/16] xfs: Simplify xfs_attr_set_args

Allison Collins
2020-01-18T22:50:52Z

Delayed attribute mechanics make frequent use of goto statements. We
can use this to further simplify xfs_attr_set_args. In this patch we
introduce one of the gotos now to help pre-simplify the routine. This
will help make proceeding patches in this area easier to read.

Signed-off-by: Allison Collins <allison.henderson@oracle.com>
---
fs/xfs/libxfs/xfs_attr.c | 71 +++++++++++++++++++++++++-----------------------
1 file changed, 37 insertions(+), 34 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
index 453ea59..90e0b2d 100644
--- a/fs/xfs/libxfs/xfs_attr.c
+++ b/fs/xfs/libxfs/xfs_attr.c
@@ -264,47 +264,50 @@ xfs_attr_set_args(
int error, error2 = 0;

/*
- * If the attribute list is non-existent or a shortform list,
- * upgrade it to a single-leaf-block attribute list.
+ * If the attribute list is non-existent or a shortform list, proceed to
+ * upgrade it to a single-leaf-block attribute list. Otherwise jump
+ * straight to leaf handling
*/
- if (dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL ||
+ if (!(dp->i_d.di_aformat == XFS_DINODE_FMT_LOCAL ||
(dp->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS &&
- dp->i_d.di_anextents == 0)) {
+ dp->i_d.di_anextents == 0)))
+ goto sf_to_leaf;

- /*
- * 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;
- }
+ /*
+ * 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;
+ /*
+ * 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.
- * Once we're done rolling the transaction we can release
- * the hold and add the attr to the leaf.
- */
- 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;
- }
+ /*
+ * 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.
+ * Once we're done rolling the transaction we can release
+ * the hold and add the attr to the leaf.
+ */
+ 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;
}

+sf_to_leaf:
+
if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
error = xfs_attr_leaf_addname(args);
if (error != -ENOSPC)
--
2.7.4