On Wed, Oct 23, 2024 at 5:58 PM Mike Snitzer <snitzer@xxxxxxxxxx> wrote: > > We do not and cannot support file locking with NFS reexport over > NFSv4.x for the same reason we don't do it for NFSv3: NFS reexport > server reboot cannot allow clients to recover locks because the source > NFS server has not rebooted, and so it is not in grace. Since the > source NFS server is not in grace, it cannot offer any guarantees that > the file won't have been changed between the locks getting lost and > any attempt to recover/reclaim them. The same applies to delegations > and any associated locks, so disallow them too. > > Add EXPORT_OP_NOLOCKSUPPORT and exportfs_lock_op_is_unsupported(), set > EXPORT_OP_NOLOCKSUPPORT in nfs_export_ops and check for it in > nfsd4_lock(), nfsd4_locku() and nfs4_set_delegation(). Clients are > not allowed to get file locks or delegations from a reexport server, > any attempts will fail with operation not supported. Are you aware that this virtually castrates NFSv4 reexport to a point that it is no longer usable in real life? If you really want this, then the only way forward is to disable and remove NFS reexport support completely. So this patch is absolutely a NO-GO, r- Thanks, Martin
