Re: [PATCH v7 00/20] nfs/nfsd: add support for localio

[Jeff Layton <jlayton@kernel.org>]

On Mon, 2024-06-24 at 12:27 -0400, Mike Snitzer wrote:
> Hi,
> 
> IANA has assigned the RPC program number 400122 for localio!
> 
> Tested with xfstests, all is passing agsint NFS v3 and v4.2 (localio
> ontop of XFS) except generic/355 (which tests if suid bit gets
> cleared
> with directio).
> 
> My git tree is here:
> https://git.kernel.org/pub/scm/linux/kernel/git/snitzer/linux.git/
> 
> This v7 is both branch nfs-localio-for-6.11 (always tracks latest)
> and nfs-localio-for-6.11.v7
> 
> Quite a bit has changed since v6:
> - Updated to use IANA assigned RPC program number 400122.
> - Thanks to Neil the localio protocol stands on its own and is
>   simplified, all of Neil's changes were included. But a patch is
>   needed to sunrpc to remove the BUG_ON if p_arglen is 0 (otherwise
>   the NULL rpc used during connection triggers the BUG_ON.
> - Reduced Kconfig knobs down to NFS_LOCALIO and NFSD_LOCALIO. Left
>   them piece-wise for reason detailed in the last patch.
> - Added MODULE_DESCRIPTION to nfs_localio module.
> - Removed all the AIO directio code from fs/nfs/localio.c because it
>   wasn't used (since nothing ever set NFS_IOHDR_ODIRECT).  But even
> if
>   enabled the async kiocb completion wasn't ever used in practice.
> 
> TODO:
> - For directio, fix kiocb so that it conveys IOCB_DIRECT to
> underlying
>   filesystem.
> - Must fix xfstests generic/355.
> - Look closer at implementing standlone SRCU to avoid bloating
>   nfsd_net -- idea of shared SRCU is very unintuitive to me...
> 
> FYI:
> - Really rather not play games with 'localio_enabled' to get all of
>   localio code to build but be disabled by default.. just too
> fiddley.
> 
> All review and comments are welcome!
> 
> Thanks,
> Mike
> 
> Mike Snitzer (11):
>   nfs_common: add NFS LOCALIO auxiliary protocol enablement
>   nfsd/localio: manage netns reference in nfsd_open_local_fh
>   nfs/nfsd: factor out {encode,decode}_opaque_fixed to nfs_xdr.h
>   SUNRPC: remove call_allocate() BUG_ON if p_arglen=0 to allow RPC
> with void arg
>   nfs: implement client support for NFS_LOCALIO_PROGRAM
>   nfsd: implement server support for NFS_LOCALIO_PROGRAM
>   nfsd: prepare to use SRCU to dereference nn->nfsd_serv
>   nfsd: use SRCU to dereference nn->nfsd_serv
>   nfsd/localio: use SRCU to dereference nn->nfsd_serv in
> nfsd_open_local_fh
>   nfs: add Documentation/filesystems/nfs/localio.rst
>   nfs/nfsd: add Kconfig options to allow localio to be enabled
> 
> NeilBrown (1):
>   SUNRPC: replace program list with program array
> 
> Trond Myklebust (3):
>   NFS: Enable localio for non-pNFS I/O
>   pnfs/flexfiles: Enable localio for flexfiles I/O
>   nfs/localio: use dedicated workqueues for filesystem read and write
> 
> Weston Andros Adamson (5):
>   nfs: pass nfs_client to nfs_initiate_pgio
>   nfs: pass descriptor thru nfs_initiate_pgio path
>   nfs: pass struct file to nfs_init_pgio and nfs_init_commit
>   sunrpc: add rpcauth_map_to_svc_cred_local
>   nfs/nfsd: add "localio" support
> 
>  Documentation/filesystems/nfs/localio.rst | 134 ++++
>  fs/Kconfig                                |   3 +
>  fs/nfs/Kconfig                            |  14 +
>  fs/nfs/Makefile                           |   1 +
>  fs/nfs/blocklayout/blocklayout.c          |   6 +-
>  fs/nfs/client.c                           |  15 +-
>  fs/nfs/filelayout/filelayout.c            |  16 +-
>  fs/nfs/flexfilelayout/flexfilelayout.c    | 131 +++-
>  fs/nfs/flexfilelayout/flexfilelayout.h    |   2 +
>  fs/nfs/flexfilelayout/flexfilelayoutdev.c |   6 +
>  fs/nfs/inode.c                            |  61 +-
>  fs/nfs/internal.h                         |  61 +-
>  fs/nfs/localio.c                          | 851
> ++++++++++++++++++++++
>  fs/nfs/nfs4xdr.c                          |  13 -
>  fs/nfs/nfstrace.h                         |  61 ++
>  fs/nfs/pagelist.c                         |  32 +-
>  fs/nfs/pnfs.c                             |  24 +-
>  fs/nfs/pnfs.h                             |   6 +-
>  fs/nfs/pnfs_nfs.c                         |   2 +-
>  fs/nfs/write.c                            |  13 +-
>  fs/nfs_common/Makefile                    |   3 +
>  fs/nfs_common/nfslocalio.c                |  72 ++
>  fs/nfsd/Kconfig                           |  14 +
>  fs/nfsd/Makefile                          |   1 +
>  fs/nfsd/filecache.c                       |  15 +-
>  fs/nfsd/localio.c                         | 327 +++++++++
>  fs/nfsd/netns.h                           |  18 +-
>  fs/nfsd/nfs4state.c                       |  25 +-
>  fs/nfsd/nfsctl.c                          |  30 +-
>  fs/nfsd/nfsd.h                            |   2 +-
>  fs/nfsd/nfssvc.c                          | 165 +++--
>  fs/nfsd/trace.h                           |   3 +-
>  fs/nfsd/vfs.h                             |   9 +
>  include/linux/nfs.h                       |   9 +
>  include/linux/nfs_fs.h                    |   2 +
>  include/linux/nfs_fs_sb.h                 |  10 +
>  include/linux/nfs_xdr.h                   |  20 +-
>  include/linux/nfslocalio.h                |  41 ++
>  include/linux/sunrpc/auth.h               |   4 +
>  include/linux/sunrpc/svc.h                |   7 +-
>  net/sunrpc/auth.c                         |  15 +
>  net/sunrpc/clnt.c                         |   1 -
>  net/sunrpc/svc.c                          |  68 +-
>  net/sunrpc/svc_xprt.c                     |   2 +-
>  net/sunrpc/svcauth_unix.c                 |   3 +-
>  45 files changed, 2116 insertions(+), 202 deletions(-)
>  create mode 100644 Documentation/filesystems/nfs/localio.rst
>  create mode 100644 fs/nfs/localio.c
>  create mode 100644 fs/nfs_common/nfslocalio.c
>  create mode 100644 fs/nfsd/localio.c
>  create mode 100644 include/linux/nfslocalio.h
> 

This is looking pretty good now! I know Chuck noted some nits and I'm
still hung up on the making nfsd_serv a void *, but I don't see it as a
show stopper and we can always fix that later. You can add:

Reviewed-by: Jeff Layton <jlayton@kernel.org>