Commit 3345746e authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Darrick J. Wong
Browse files

xfs: simplify xfs_map_blocks by using xfs_iext_lookup_extent directly 



xfs_bmapi_read adds zero value in xfs_map_blocks.  Replace it with a
direct call to the low-level extent lookup function.

Note that we now always pass a 0 length to the trace points as we ask
for an unspecified len.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarBrian Foster <bfoster@redhat.com>
Reviewed-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
parent 060d4eaa

fs/xfs/xfs_aops.c

+5 −14
Original line number Diff line number Diff line
@@ -375,7 +375,6 @@ xfs_map_blocks( 
	int			whichfork = XFS_DATA_FORK;

	struct xfs_iext_cursor	icur;

	int			error = 0;

	int			nimaps = 1;



	if (XFS_FORCED_SHUTDOWN(mp))

		return -EIO;
@@ -431,24 +430,16 @@ xfs_map_blocks( 
	 * offset.  This will convert delayed allocations (including COW ones)

	 * into real extents.

	 */

	error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb,

				&imap, &nimaps, XFS_BMAPI_ENTIRE);

	if (!xfs_iext_lookup_extent(ip, &ip->i_df, offset_fsb, &icur, &imap))

		imap.br_startoff = end_fsb;	/* fake a hole past EOF */

	xfs_iunlock(ip, XFS_ILOCK_SHARED);

	if (error)

		return error;



	if (!nimaps) {

		/*

		 * Lookup returns no match? Beyond eof? regardless,

		 * return it as a hole so we don't write it

		 */

	if (imap.br_startoff > offset_fsb) {

		/* landed in a hole or beyond EOF */

		imap.br_blockcount = imap.br_startoff - offset_fsb;

		imap.br_startoff = offset_fsb;

		imap.br_blockcount = end_fsb - offset_fsb;

		imap.br_startblock = HOLESTARTBLOCK;

		wpc->io_type = XFS_IO_HOLE;

	} else if (imap.br_startblock == HOLESTARTBLOCK) {

		/* landed in a hole */

		wpc->io_type = XFS_IO_HOLE;

	} else {

		if (isnullstartblock(imap.br_startblock)) {

			/* got a delalloc extent */

CRA Git | Maintained and supported by SUSTech CRA and CCSE