From:   Scott Mayhew <smayhew@redhat.com>
To:     steved@redhat.com
Cc:     bfields@fieldses.org, jlayton@kernel.org, linux-nfs@vger.kernel.org
Subject: [nfs-utils PATCH RFC v3 0/8] restore nfsdcld
Date:   Tue, 26 Mar 2019 18:07:22 -0400
Message-Id: <20190326220730.3763-1-smayhew@redhat.com>
Sender: linux-nfs-owner@vger.kernel.org
Precedence: bulk

When nfsdcld was released, it was quickly deprecated in favor of the
nfsdcltrack usermodehelper, so as to not require another running daemon.
The nfsdcld code was removed from nfs-utils in 2012.  That prevents
NFSv4 clients from reclaiming locks from nfsd's running in containers,
since neither nfsdcltrack nor the legacy client tracking code work in
containers.  These patches restore the nfsdcld code.

These patches are intended to go alongside some kernel patches that
introduce an enhancement that allows nfsd to "slurp" up the client
records during client tracking initialization and store them internally
in hash table.  This enables nfsd to check whether an NFSv4 client is
allowed to reclaim without having to do an upcall to nfsdcld.  It also
allows nfsd to decide to end the v4 grace period early if the number of
RECLAIM_COMPLETE operations it has received from "known" clients is
equal to the number of entries in the hash table.  It also allows nfsd
to skip the v4 grace period altogether if it knows there are no clients
allowed to reclaim.

The new nfsdcld code will work with older kernels, however in that case
there is no ability for nfsd to exit the grace period early or skip the
grace period altogether.

v3:
- removed PathExists restriction from the nfsdcld.service file
- added the ability to do a one-time upgrade from older client tracking
  methods (i.e. nfsdcltrack and/or the legacy v4recovery dir)
v2:
- Use sqlite3_column_int64() instead of sqlite3_column_int() to query
  the current & recovery values from the grace table
- Uncommented the nfsdcld section header in nfs.conf

Scott Mayhew (8):
  Revert "nfsdcltrack: remove the nfsdcld daemon"
  nfsdcld: move nfsdcld to its own directory
  nfsdcld: a few enhancements
  nfsdcld: remove some unused functions
  nfsdcld: the -p option should specify the rpc_pipefs mountpoint
  nfsdcld: add /etc/nfs.conf support
  systemd: add a unit file for nfsdcld
  nfsdcld: add a facility for migrating from older client tracking
    methods

 .gitignore                   |    1 +
 configure.ac                 |   23 +
 nfs.conf                     |    4 +
 support/include/cld.h        |    1 +
 systemd/nfs-server.service   |    2 +
 systemd/nfsdcld.service      |   10 +
 utils/Makefile.am            |    4 +
 utils/nfsdcld/Makefile.am    |   19 +
 utils/nfsdcld/cld-internal.h |   33 +
 utils/nfsdcld/legacy.c       |  180 ++++++
 utils/nfsdcld/legacy.h       |   24 +
 utils/nfsdcld/nfsdcld.c      |  774 ++++++++++++++++++++++++
 utils/nfsdcld/nfsdcld.man    |  199 ++++++
 utils/nfsdcld/sqlite.c       | 1109 ++++++++++++++++++++++++++++++++++
 utils/nfsdcld/sqlite.h       |   35 ++
 15 files changed, 2418 insertions(+)
 create mode 100644 systemd/nfsdcld.service
 create mode 100644 utils/nfsdcld/Makefile.am
 create mode 100644 utils/nfsdcld/cld-internal.h
 create mode 100644 utils/nfsdcld/legacy.c
 create mode 100644 utils/nfsdcld/legacy.h
 create mode 100644 utils/nfsdcld/nfsdcld.c
 create mode 100644 utils/nfsdcld/nfsdcld.man
 create mode 100644 utils/nfsdcld/sqlite.c
 create mode 100644 utils/nfsdcld/sqlite.h

-- 
2.17.2