Commit f49af061 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Darrick J. Wong
Browse files

xfs: check the flags earlier in xfs_attr_match 



Checking the flags match is much cheaper than a memcmp, so do it early
on in xfs_attr_match, and also add a little helper to calculate the
match mask right under the comment explaining the logic for it.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarDarrick J. Wong <djwong@kernel.org>
Signed-off-by: default avatarDarrick J. Wong <djwong@kernel.org>
parent 63211876

fs/xfs/libxfs/xfs_attr_leaf.c

+10 −9
Original line number Diff line number Diff line
@@ -507,6 +507,13 @@ xfs_attr3_leaf_read( 
 * INCOMPLETE flag will not be set in attr->attr_filter, but rather

 * XFS_DA_OP_RECOVERY will be set in args->op_flags.

 */

static inline unsigned int xfs_attr_match_mask(const struct xfs_da_args *args)

{

	if (args->op_flags & XFS_DA_OP_RECOVERY)

		return XFS_ATTR_NSP_ONDISK_MASK;

	return XFS_ATTR_NSP_ONDISK_MASK | XFS_ATTR_INCOMPLETE;

}



static bool

xfs_attr_match(

	struct xfs_da_args	*args,
@@ -514,21 +521,15 @@ xfs_attr_match( 
	const unsigned char	*name,

	unsigned int		namelen)

{

	unsigned int		mask = xfs_attr_match_mask(args);



	if (args->namelen != namelen)

		return false;

	if ((args->attr_filter & mask) != (attr_flags & mask))

		return false;

	if (memcmp(args->name, name, namelen) != 0)

		return false;



	/* Recovery ignores the INCOMPLETE flag. */

	if ((args->op_flags & XFS_DA_OP_RECOVERY) &&

	    args->attr_filter == (attr_flags & XFS_ATTR_NSP_ONDISK_MASK))

		return true;



	/* All remaining matches need to be filtered by INCOMPLETE state. */

	if (args->attr_filter !=

	    (attr_flags & (XFS_ATTR_NSP_ONDISK_MASK | XFS_ATTR_INCOMPLETE)))

		return false;

	return true;

}