diff options
author | NeilBrown <neilb@suse.com> | 2018-12-03 11:30:30 +1100 |
---|---|---|
committer | Anna Schumaker <Anna.Schumaker@Netapp.com> | 2018-12-19 13:52:45 -0500 |
commit | a534ecb013bfc58a7f03653c7f2976bc341da98f (patch) | |
tree | 55d3c1b4a992afc33c28b5d1d4e37943de4b1389 | |
parent | 1a80810fbf238e6dbaaaa5262a76d328ace21376 (diff) | |
download | linux-a534ecb013bfc58a7f03653c7f2976bc341da98f.tar.bz2 |
NFSv4: add cl_root_cred for use when machine cred is not available.
NFSv4 state management tries a root credential when no machine
credential is available, as can happen with kerberos.
It does this by replacing the cl_machine_cred with a root credential.
This means that any user of the machine credential needs to take
a lock while getting a reference to the machine credential, which is
a little cumbersome.
So introduce an explicit cl_root_cred, and never free either
credential until client shutdown. This means that no locking
is needed to reference these credentials. Future patches
will make use of this.
This is only a temporary addition. both cl_machine_cred and
cl_root_cred will disappear later in the series.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
-rw-r--r-- | fs/nfs/client.c | 2 | ||||
-rw-r--r-- | fs/nfs/nfs4state.c | 20 | ||||
-rw-r--r-- | include/linux/nfs_fs_sb.h | 1 |
3 files changed, 15 insertions, 8 deletions
diff --git a/fs/nfs/client.c b/fs/nfs/client.c index 96d5f8135eb9..cce151776709 100644 --- a/fs/nfs/client.c +++ b/fs/nfs/client.c @@ -248,6 +248,8 @@ void nfs_free_client(struct nfs_client *clp) if (clp->cl_machine_cred != NULL) put_rpccred(clp->cl_machine_cred); + if (clp->cl_root_cred != NULL) + put_rpccred(clp->cl_root_cred); put_net(clp->cl_net); put_nfs_version(clp->cl_nfs_mod); diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index d8decf2ec48f..511bcdee98f5 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -166,24 +166,28 @@ out: struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp) { - struct rpc_cred *cred = NULL; + struct rpc_cred *cred = clp->cl_root_cred; - if (clp->cl_machine_cred != NULL) - cred = get_rpccred(clp->cl_machine_cred); + if (!cred) + cred = clp->cl_machine_cred; + if (cred) + return get_rpccred(cred); return cred; } static void nfs4_root_machine_cred(struct nfs_client *clp) { - struct rpc_cred *cred, *new; + struct rpc_cred *new; new = rpc_lookup_machine_cred(NULL); spin_lock(&clp->cl_lock); - cred = clp->cl_machine_cred; - clp->cl_machine_cred = new; + if (clp->cl_root_cred == NULL) { + clp->cl_root_cred = new; + new = NULL; + } spin_unlock(&clp->cl_lock); - if (cred != NULL) - put_rpccred(cred); + if (new != NULL) + put_rpccred(new); } static struct rpc_cred * diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h index 0fc0b9135d46..fea51b44fe50 100644 --- a/include/linux/nfs_fs_sb.h +++ b/include/linux/nfs_fs_sb.h @@ -59,6 +59,7 @@ struct nfs_client { u32 cl_minorversion;/* NFSv4 minorversion */ struct rpc_cred *cl_machine_cred; + struct rpc_cred *cl_root_cred; /* Use when machine_cred is ineffective */ #if IS_ENABLED(CONFIG_NFS_V4) struct list_head cl_ds_clients; /* auth flavor data servers */ |