xfs: adjust checks for cross-AG reaping issues

While analyzing the reaping code for the previous patch, I studied the
xfs_fsblock_t code to reconstruct how this code works.  AGs have a
superblock at the start of each AG which means that regions in the
xfsb_bitmap (aka xfs_fsblock_t bitmap) cannot cross an AG boundary, so
we don't need a loop here like we do for xfs_rtblock_t bitmaps.

However, the checks here are not quite right -- there can be quite a lot
of reserved space in COW forks, which means that the bitmap extent
actually can exceed XFS_MAX_BMBT_EXTLEN.  We also don't have an explicit
debugging check that we never cross AGs, so add that here.

Cc: stable@vger.kernel.org # v6.8
Fixes: 66da11280f7ecd ("xfs: reintroduce reaping of file metadata blocks to xrep_reap_extents")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>

0 files changed, 0 insertions, 0 deletions