From: Darrick J. Wong <djwong@xxxxxxxxxx> The newer swapext implementations in the kernel run at a high enough level (above the bmap layer) that it's no longer required to manipulate bs_forkoff by creating garbage xattrs to get the extent tree that we want. If we detect the newer algorithms, skip this error prone step. Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> --- fsr/xfs_fsr.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/fsr/xfs_fsr.c b/fsr/xfs_fsr.c index c6dbfb22a..22e134adf 100644 --- a/fsr/xfs_fsr.c +++ b/fsr/xfs_fsr.c @@ -999,6 +999,20 @@ fsr_setup_attr_fork( if (!(bstatp->bs_xflags & FS_XFLAG_HASATTR)) return 0; + /* + * If the filesystem has the ability to perform atomic file mapping + * exchanges, the file extent swap implementation uses a higher level + * algorithm that calls into the bmap code instead of playing games + * with swapping the extent forks. + * + * This new functionality does not require specific values of + * bs_forkoff, unlike the old fork swap code. Leave the extended + * attributes alone if we know we're not using the old fork swap + * strategy. This eliminates a major source of runtime errors in fsr. + */ + if (fsgeom.flags & XFS_FSOP_GEOM_FLAGS_EXCHANGE_RANGE) + return 0; + /* * use the old method if we have attr1 or the kernel does not yet * support passing the fork offset in the bulkstat data.
