[PATCH v1 0/3] nfsdctl: list NFSv4 clients

[Prabhakar Pujeri <prabhakar.pujeri@dell.com>]

Add the userspace consumer for the companion NFSD Netlink client-state
series, whose cover Message-ID is:

  <cover.1787638668.git.prabhakar.pujeri@dell.com>

The series mirrors the kernel ABI split:

  1. Display the explicit recovery-grace value returned by threads-get.
  2. Add a privileged `nfsdctl clients` table for basic client state.
  3. Extend the table with session and stateid record counts.

Attribute presence remains the compatibility boundary. An older kernel
omits the grace value, and missing count attributes are displayed as
dashes. The bundled UAPI header permits building before the new kernel
header is installed. The configure probe requires the final count
attribute, so a system header containing only the base client command also
falls back to the complete bundled copy.

Validation performed:

  - full nfs-utils build at each applicable patch state
  - final `make check`: no failures; one environment-dependent test skipped
  - bundled nfsd Netlink UAPI compared byte-for-byte with the kernel copy
  - two-vCPU QEMU test with a live NFSv4.2 loopback mount
  - grace yes/no transitions displayed by `nfsdctl threads`
  - live client row showing one session, open stateid, lock stateid, and
    delegation stateid; zero layout stateids
  - callback, reclaim, lease, peer-address, and client-ID fields checked

The series is based on the current nfs-utils master branch. The exact base
is recorded in the base-commit trailer below.

Prabhakar Pujeri (3):
  nfsdctl: report NFSv4 grace state
  nfsdctl: add a command to list NFSv4 clients
  nfsdctl: display per-client NFSv4 state usage

 configure.ac                   |   2 +-
 support/include/nfsd_netlink.h |  41 +++++
 utils/nfsdctl/nfsdctl.8        |  22 ++-
 utils/nfsdctl/nfsdctl.adoc     |  15 +-
 utils/nfsdctl/nfsdctl.c        | 268 +++++++++++++++++++++++++++++++++
 5 files changed, 345 insertions(+), 3 deletions(-)


base-commit: 67ed1bdb1af1c70a5fd3b377a997401b7676b827
-- 
2.54.0