xfs: use XFS_B_TO_FSB in xfs_ioctl_setattr

Clean up xfs_ioctl_setattr a bit by using XFS_B_TO_FSB.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>

fs/xfs/xfs_ioctl.c

@@ -1520,12 +1520,12 @@ xfs_ioctl_setattr(
 	 * are set on the inode then unconditionally clear the extent size hint.
 	 */
 	if (ip->i_d.di_flags & (XFS_DIFLAG_EXTSIZE | XFS_DIFLAG_EXTSZINHERIT))
-		ip->i_extsize = fa->fsx_extsize >> mp->m_sb.sb_blocklog;
+		ip->i_extsize = XFS_B_TO_FSB(mp, fa->fsx_extsize);
 	else
 		ip->i_extsize = 0;
 	if (xfs_sb_version_has_v3inode(&mp->m_sb) &&
 	    (ip->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE))
-		ip->i_cowextsize = fa->fsx_cowextsize >> mp->m_sb.sb_blocklog;
+		ip->i_cowextsize = XFS_B_TO_FSB(mp, fa->fsx_cowextsize);
 	else
 		ip->i_cowextsize = 0;