On Wed, Jul 10, 2024 at 07:59:58PM -0700, Darrick J. Wong wrote: > Hmm. If we don't support reflink + forcealign ATM, then shouldn't the > superblock verifier or xfs_fs_fill_super fail the mount so that old > kernels won't abruptly emit EFSCORRUPTED errors if a future kernel adds > support for forcealign'd cow and starts writing out files with both > iflags set? Yes. > That said, if the bs>ps patchset lands, then I think forcealign cow is > a simple matter of setting the min folio order to the forcealign size > and making sure that we always write out entire folios if any of the > blocks cached by the folio is shared. Direct writes to forcealigned > shared files probably has to be aligned to the forcealign size or fall > back to buffered writes for cow. It has all the same problems as rtexsize > 1 + reflink, and suppoting it will require raiding your patch stack. Or better just wait until we've got all that in now that we're actively working on it.
