Re: [PATCH v3 00/28] vfs/nfsd: add support for CB_NOTIFY callbacks in directory delegations

["Chuck Lever" <cel@kernel.org>]

On Tue, Apr 28, 2026, at 3:09 AM, Jeff Layton wrote:
> Re-posting the set per Christian's request. The only difference in this
> version is a small error handling fix in alloc_init_dir_deleg(). The old
> version could crash since release_pages() can't handle an array with
> NULL pointers in it.
>
> ---------------------------------8<------------------------------------
>
> This patchset builds on the directory delegation work we did a few
> months ago, to add support for CB_NOTIFY callbacks for some events. In
> particular, creates, unlinks and renames. The server also sends updated
> directory attributes in the notifications. With this support, the client
> can register interest in a directory and get notifications about changes
> within it without losing its lease.
>
> The series starts with patches to allow the vfs to ignore certain types
> of events on directories. nfsd can then request these sorts of
> delegations on directories, and then set up inotify watches on the
> directory to trigger sending CB_NOTIFY events.
>
> This has mainly been tested with pynfs, with some new testcases that
> I'll be posting soon. They seem to work fine with those tests, but I
> don't think we'll want to merge these until we have a complete
> client-side implementation to test against.
>
> Signed-off-by: Jeff Layton <jlayton@kernel.org>
> ---
> Changes in v3:
> - Fix error handling in alloc_init_dir_deleg()
> - Link to v2: 
> https://lore.kernel.org/r/20260416-dir-deleg-v2-0-851426a550f6@kernel.org
>
> Changes in v2:
> - Fix __break_lease handling with different lease types on flc_lease 
> list
> - Add FSNOTIFY_EVENT_RENAME data type to properly handle 
> cross-directory rename events
> - Display fsnotify mask symbolically in tracepoints
> - New tracepoint in fsnotify()
> - Recalc fsnotify mask after unlocking lease instead of before
> - Don't notify client that is making the changes
> - After sending CB_NOTIFY, requeue if new events came in while running
> - Document removal of NFS4_VERIFIER_SIZE/NFS4_FHSIZE from UAPI headers
> - Properly release nfsd_dir_fsnotify_group on server shutdown
> - Link to v1: 
> https://lore.kernel.org/r/20260407-dir-deleg-v1-0-aaf68c478abd@kernel.org
>
> ---
> Jeff Layton (28):
>       filelock: pass current blocking lease to 
> trace_break_lease_block() rather than "new_fl"
>       filelock: add support for ignoring deleg breaks for dir change 
> events
>       filelock: add a tracepoint to start of break_lease()
>       filelock: add an inode_lease_ignore_mask helper
>       fsnotify: new tracepoint in fsnotify()
>       fsnotify: add fsnotify_modify_mark_mask()
>       fsnotify: add FSNOTIFY_EVENT_RENAME data type
>       nfsd: check fl_lmops in nfsd_breaker_owns_lease()
>       nfsd: add protocol support for CB_NOTIFY
>       nfs_common: add new NOTIFY4_* flags proposed in RFC8881bis
>       nfsd: allow nfsd to get a dir lease with an ignore mask
>       nfsd: update the fsnotify mark when setting or removing a dir 
> delegation
>       nfsd: make nfsd4_callback_ops->prepare operation bool return
>       nfsd: add callback encoding and decoding linkages for CB_NOTIFY
>       nfsd: use RCU to protect fi_deleg_file
>       nfsd: add data structures for handling CB_NOTIFY
>       nfsd: add notification handlers for dir events
>       nfsd: add tracepoint to dir_event handler
>       nfsd: apply the notify mask to the delegation when requested
>       nfsd: add helper to marshal a fattr4 from completed args
>       nfsd: allow nfsd4_encode_fattr4_change() to work with no export
>       nfsd: send basic file attributes in CB_NOTIFY
>       nfsd: allow encoding a filehandle into fattr4 without a svc_fh
>       nfsd: add a fi_connectable flag to struct nfs4_file
>       nfsd: add the filehandle to returned attributes in CB_NOTIFY
>       nfsd: properly track requested child attributes
>       nfsd: track requested dir attributes
>       nfsd: add support to CB_NOTIFY for dir attribute changes
>
>  Documentation/sunrpc/xdr/nfs4_1.x    | 264 ++++++++++++++-
>  fs/attr.c                            |   2 +-
>  fs/locks.c                           | 118 +++++--
>  fs/namei.c                           |  31 +-
>  fs/nfsd/filecache.c                  |  70 +++-
>  fs/nfsd/nfs4callback.c               |  60 +++-
>  fs/nfsd/nfs4layouts.c                |   5 +-
>  fs/nfsd/nfs4proc.c                   |  17 +
>  fs/nfsd/nfs4state.c                  | 551 ++++++++++++++++++++++++++++----
>  fs/nfsd/nfs4xdr.c                    | 323 +++++++++++++++++--
>  fs/nfsd/nfs4xdr_gen.c                | 601 ++++++++++++++++++++++++++++++++++-
>  fs/nfsd/nfs4xdr_gen.h                |  20 +-
>  fs/nfsd/state.h                      |  72 ++++-
>  fs/nfsd/trace.h                      |  23 ++
>  fs/nfsd/xdr4.h                       |   5 +
>  fs/nfsd/xdr4cb.h                     |  12 +
>  fs/notify/fsnotify.c                 |   5 +
>  fs/notify/mark.c                     |  29 ++
>  fs/posix_acl.c                       |   4 +-
>  fs/xattr.c                           |   4 +-
>  include/linux/filelock.h             |  54 +++-
>  include/linux/fsnotify.h             |   8 +-
>  include/linux/fsnotify_backend.h     |  21 ++
>  include/linux/nfs4.h                 | 127 --------
>  include/linux/sunrpc/xdrgen/nfs4_1.h | 291 ++++++++++++++++-
>  include/trace/events/filelock.h      |  38 ++-
>  include/trace/events/fsnotify.h      |  51 +++
>  include/trace/misc/fsnotify.h        |  35 ++
>  include/uapi/linux/nfs4.h            |   2 -
>  29 files changed, 2519 insertions(+), 324 deletions(-)
> ---
> base-commit: f4d71dd7fd9cec357c32431fa55c107b96008312
> change-id: 20260325-dir-deleg-339066dd1017
>
> Best regards,
> -- 
> Jeff Layton <jlayton@kernel.org>

For the series:

Acked-by: Chuck Lever <chuck.lever@oracle.com>


-- 
Chuck Lever