Re: [PATCH v2 00/11] vfs: recall-only directory delegations for knfsd

On Fri, 17 Oct 2025, Jeff Layton wrote:

A smaller variation of the v1 patchset that I posted earlier this week.
Neil's review inspired me to get rid of the lm_may_setlease operation
and to do the conflict resolution internally inside of nfsd. That means
a smaller VFS-layer change, and an overall reduction in code.

This patchset adds support for directory delegations to nfsd. This
version only supports recallable delegations. There is no CB_NOTIFY
support yet. I have patches for those, but we've decided to add that
support in a later kernel once we get some experience with this part.
Anna is working on the client-side pieces.

It would be great if we could get into linux-next soon so that it can be
merged for v6.19. Christian, could you pick up the vfs/filelock patches,
and Chuck pick up the nfsd patches?

Thanks!
Jeff

[1]: https://lore.kernel.org/all/20240315-dir-deleg-v1-0-a1d6209a3654@kernel.org/ (local)

Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
Changes in v2:
- handle lease conflict resolution inside of nfsd
- drop the lm_may_setlease lock_manager operation
- just add extra argument to vfs_create() instead of creating wrapper
- don't allocate fsnotify_mark for open directories
- Link to v1: https://lore.kernel.org/r/20251013-dir-deleg-ro-v1-0-406780a70e5e@kernel.org (local)

---
Jeff Layton (11):
      filelock: push the S_ISREG check down to ->setlease handlers
      vfs: add try_break_deleg calls for parents to vfs_{link,rename,unlink}
      vfs: allow mkdir to wait for delegation break on parent
      vfs: allow rmdir to wait for delegation break on parent
      vfs: break parent dir delegations in open(..., O_CREAT) codepath
      vfs: make vfs_create break delegations on parent directory
      vfs: make vfs_mknod break delegations on parent directory
      filelock: lift the ban on directory leases in generic_setlease
      nfsd: allow filecache to hold S_IFDIR files
      nfsd: allow DELEGRETURN on directories
      nfsd: wire up GET_DIR_DELEGATION handling

vfs_symlink() is missing from the updated APIs.  Surely that needs to be
able to wait for a delegation to break.

vfs_mkobj() maybe does too, but I could easily turn a blind eye to that.

I haven't looked properly at the last patch but all the other could have
 Reviewed-by: NeilBrown [off-list ref]

once the vfs_symlink() omission is fixed.

NeilBrown