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

From: NeilBrown
Date: Tue Nov 06 2018 - 23:13:35 EST


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

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