Re: [PATCH v11 20/25] xfs: Simplify xfs_attr_leaf_addname

Darrick J. Wong
2020-07-21T23:39:15Z

On Mon, Jul 20, 2020 at 05:16:01PM -0700, Allison Collins wrote:
> Invert the rename logic in xfs_attr_leaf_addname to simplify the
> delayed attr logic later.
>
> Signed-off-by: Allison Collins <allison.henderson@oracle.com>
> Reviewed-by: Brian Foster <bfoster@redhat.com>

Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>

--D

> ---
> fs/xfs/libxfs/xfs_attr.c | 107 ++++++++++++++++++++++++-----------------------
> 1 file changed, 55 insertions(+), 52 deletions(-)
>
> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
> index f993af5..ca1e851 100644
> --- a/fs/xfs/libxfs/xfs_attr.c
> +++ b/fs/xfs/libxfs/xfs_attr.c
> @@ -695,68 +695,71 @@ xfs_attr_leaf_addname(
> return error;
> }
>
> - /*
> - * If this is an atomic rename operation, we must "flip" the
> - * incomplete flags on the "new" and "old" attribute/value pairs
> - * so that one disappears and one appears atomically. Then we
> - * must remove the "old" attribute/value pair.
> - */
> - if (args->op_flags & XFS_DA_OP_RENAME) {
> + if (!(args->op_flags & XFS_DA_OP_RENAME)) {
> /*
> - * In a separate transaction, set the incomplete flag on the
> - * "old" attr and clear the incomplete flag on the "new" attr.
> - */
> - error = xfs_attr3_leaf_flipflags(args);
> - if (error)
> - return error;
> - /*
> - * Commit the flag value change and start the next trans in
> - * series.
> + * Added a "remote" value, just clear the incomplete flag.
> */
> - error = xfs_trans_roll_inode(&args->trans, args->dp);
> - if (error)
> - return error;
> + if (args->rmtblkno > 0)
> + error = xfs_attr3_leaf_clearflag(args);
>
> - /*
> - * Dismantle the "old" attribute/value pair by removing
> - * a "remote" value (if it exists).
> - */
> - xfs_attr_restore_rmt_blk(args);
> + return error;
> + }
>
> - if (args->rmtblkno) {
> - error = xfs_attr_rmtval_invalidate(args);
> - if (error)
> - return error;
> + /*
> + * If this is an atomic rename operation, we must "flip" the incomplete
> + * flags on the "new" and "old" attribute/value pairs so that one
> + * disappears and one appears atomically. Then we must remove the "old"
> + * attribute/value pair.
> + *
> + * In a separate transaction, set the incomplete flag on the "old" attr
> + * and clear the incomplete flag on the "new" attr.
> + */
>
> - error = xfs_attr_rmtval_remove(args);
> - if (error)
> - return error;
> - }
> + error = xfs_attr3_leaf_flipflags(args);
> + if (error)
> + return error;
> + /*
> + * Commit the flag value change and start the next trans in series.
> + */
> + error = xfs_trans_roll_inode(&args->trans, args->dp);
> + if (error)
> + return error;
>
> - /*
> - * Read in the block containing the "old" attr, then
> - * remove the "old" attr from that block (neat, huh!)
> - */
> - error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno,
> - &bp);
> + /*
> + * Dismantle the "old" attribute/value pair by removing a "remote" value
> + * (if it exists).
> + */
> + xfs_attr_restore_rmt_blk(args);
> +
> + if (args->rmtblkno) {
> + error = xfs_attr_rmtval_invalidate(args);
> if (error)
> return error;
>
> - xfs_attr3_leaf_remove(bp, args);
> -
> - /*
> - * If the result is small enough, shrink it all into the inode.
> - */
> - forkoff = xfs_attr_shortform_allfit(bp, dp);
> - if (forkoff)
> - error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
> - /* bp is gone due to xfs_da_shrink_inode */
> - } else if (args->rmtblkno > 0) {
> - /*
> - * Added a "remote" value, just clear the incomplete flag.
> - */
> - error = xfs_attr3_leaf_clearflag(args);
> + error = xfs_attr_rmtval_remove(args);
> + if (error)
> + return error;
> }
> +
> + /*
> + * Read in the block containing the "old" attr, then remove the "old"
> + * attr from that block (neat, huh!)
> + */
> + error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno,
> + &bp);
> + if (error)
> + return error;
> +
> + xfs_attr3_leaf_remove(bp, args);
> +
> + /*
> + * If the result is small enough, shrink it all into the inode.
> + */
> + forkoff = xfs_attr_shortform_allfit(bp, dp);
> + if (forkoff)
> + error = xfs_attr3_leaf_to_shortform(bp, args, forkoff);
> + /* bp is gone due to xfs_da_shrink_inode */
> +
> return error;
> }
>
> --
> 2.7.4
>