Re: [PATCH 00/23 - V4] NFS: Remove generic RPC credentials.

["Schumaker, Anna" <Anna.Schumaker@netapp.com>]

Hi Neil,

On Fri, 2018-11-30 at 10:19 +1100, NeilBrown wrote:
> Hi,
>  has anyone else had a chance to look at this yet?
> 
>  There is a small conflict now due to
>         SUNRPC: Fix a bogus get/put in generic_key_to_expire()
>  Should I resend with that fixed up?

The patches look okay to me.  And yes, please resend them with the fix up.

Thanks,
Anna

> 
> Thanks,
> NeilBrown
> 
> 
> On Wed, Nov 07 2018, NeilBrown wrote:
> 
> > This is an updated version of a series I sent in Feb of this year.
> > Since then there have only been minor improvement and updates to sync
> > with the changing kernel.
> > 
> > There doesn't seem to be a maintainer for the 'cred' code, so I don't
> > know who to ask to approve the first 4 patches.  Maybe if the NFS
> > team like them, they can just go to Linus with a note for him to look
> > at them if he wants to.
> > 
> > The original motivation for this was performance.  In some
> > circumstances the cred caches can get big and particularly can get
> > long chains.  The hash function has been changed at least once to
> > improve the hashing and it still isn't perfect.
> > Rather than improving pruning of the cache, or resizing the hashtable
> > etc, it is easiest to just get rid of it.
> > 
> > As well as discarding generic credentials completely (using 'struct
> > cred' instead), we also stop storing AUTH_UNIX credentials in a hash
> > table - that brings no value.  Just allocate as needed and discard
> > when finished with.
> > So the only hash table will still have is for AUTH_GSS.
> > One of the main triggers for hashtable problems was users changing
> > groups a lot, so there would be many entries for the one user, each
> > with a different set of groups.  That doesn't apply for
> > AUTH_GSS as the groupids on the client are ignored.
> > 
> > That was the original motivation, but as I worked on it, I realized
> > that it was making a log of code simpler.
> > 
> >  44 files changed, 550 insertions(+), 925 deletions(-)
> > 
> > That is sufficient motivation in itself I think.
> > 
> > Review comments most welcome.
> > 
> > Thanks,
> > NeilBrown
> > 
> > 
> > ---
> > 
> > NeilBrown (23):
> >       cred: add cred_fscmp() for comparing creds.
> >       cred: add get_cred_rcu()
> >       cred: export get_task_cred().
> >       cred: allow get_cred() and put_cred() to be given NULL.
> >       SUNRPC: add 'struct cred *' to auth_cred and rpc_cred
> >       SUNRPC: remove groupinfo from struct auth_cred.
> >       SUNRPC: remove uid and gid from struct auth_cred
> >       SUNRPC: remove machine_cred field from struct auth_cred
> >       NFSv4: add cl_root_cred for use when machine cred is not available.
> >       NFSv4: don't require lock for get_renew_cred or get_machine_cred
> >       SUNRPC: discard RPC_DO_ROOTOVERRIDE()
> >       NFS/SUNRPC: don't lookup machine credential until rpcauth_bindcred().
> >       SUNRPC: introduce RPC_TASK_NULLCREDS to request auth_none
> >       SUNRPC: add side channel to use non-generic cred for rpc call.
> >       NFS: move credential expiry tracking out of SUNRPC into NFS.
> >       SUNRPC: remove RPCAUTH_AUTH_NO_CRKEY_TIMEOUT
> >       NFS: change access cache to use 'struct cred'.
> >       NFS: struct nfs_open_dir_context: convert rpc_cred pointer to cred.
> >       NFS/NFSD/SUNRPC: replace generic creds with 'struct cred'.
> >       SUNRPC: remove generic cred code.
> >       SUNRPC: remove crbind rpc_cred operation
> >       SUNRPC: simplify auth_unix.
> >       SUNRPC discard cr_uid from struct rpc_cred.
> > 
> > 
> >  fs/lockd/clntproc.c                       |    6 -
> >  fs/nfs/blocklayout/blocklayout.c          |    2 
> >  fs/nfs/client.c                           |    9 -
> >  fs/nfs/delegation.c                       |   28 +--
> >  fs/nfs/delegation.h                       |   10 -
> >  fs/nfs/dir.c                              |   59 ++----
> >  fs/nfs/flexfilelayout/flexfilelayout.c    |   64 +++---
> >  fs/nfs/flexfilelayout/flexfilelayout.h    |    8 -
> >  fs/nfs/flexfilelayout/flexfilelayoutdev.c |   16 +-
> >  fs/nfs/inode.c                            |   13 +
> >  fs/nfs/internal.h                         |    8 -
> >  fs/nfs/nfs3proc.c                         |    4 
> >  fs/nfs/nfs4_fs.h                          |   65 +++---
> >  fs/nfs/nfs4client.c                       |    4 
> >  fs/nfs/nfs4proc.c                         |  150 +++++++--------
> >  fs/nfs/nfs4renewd.c                       |    9 -
> >  fs/nfs/nfs4session.c                      |    5 
> >  fs/nfs/nfs4state.c                        |  129 ++++++-------
> >  fs/nfs/pagelist.c                         |    2 
> >  fs/nfs/pnfs.c                             |   14 +
> >  fs/nfs/pnfs.h                             |   10 -
> >  fs/nfs/pnfs_dev.c                         |    4 
> >  fs/nfs/pnfs_nfs.c                         |    2 
> >  fs/nfs/proc.c                             |    2 
> >  fs/nfs/unlink.c                           |   15 -
> >  fs/nfs/write.c                            |   24 ++
> >  fs/nfsd/nfs4callback.c                    |   31 +--
> >  fs/nfsd/state.h                           |    2 
> >  include/linux/cred.h                      |   26 ++-
> >  include/linux/nfs_fs.h                    |   13 +
> >  include/linux/nfs_fs_sb.h                 |    2 
> >  include/linux/nfs_xdr.h                   |   16 +-
> >  include/linux/sunrpc/auth.h               |   51 -----
> >  include/linux/sunrpc/clnt.h               |    1 
> >  include/linux/sunrpc/sched.h              |    6 -
> >  kernel/cred.c                             |   58 ++++++
> >  net/sunrpc/Makefile                       |    2 
> >  net/sunrpc/auth.c                         |  116 ++++++-----
> >  net/sunrpc/auth_generic.c                 |  299 --------------------------
> > ---
> >  net/sunrpc/auth_gss/auth_gss.c            |   45 +---
> >  net/sunrpc/auth_null.c                    |    4 
> >  net/sunrpc/auth_unix.c                    |  110 +++--------
> >  net/sunrpc/clnt.c                         |   26 +--
> >  net/sunrpc/sched.c                        |    5 
> >  44 files changed, 550 insertions(+), 925 deletions(-)
> >  delete mode 100644 net/sunrpc/auth_generic.c
> > 
> > --
> > Signature