diff options
Diffstat (limited to 'net/sunrpc/svcauth.c')
| -rw-r--r-- | net/sunrpc/svcauth.c | 74 |
1 files changed, 53 insertions, 21 deletions
diff --git a/net/sunrpc/svcauth.c b/net/sunrpc/svcauth.c index bb8db3cb8032..775b8c94265b 100644 --- a/net/sunrpc/svcauth.c +++ b/net/sunrpc/svcauth.c @@ -27,12 +27,32 @@ extern struct auth_ops svcauth_null; extern struct auth_ops svcauth_unix; -static DEFINE_SPINLOCK(authtab_lock); -static struct auth_ops *authtab[RPC_AUTH_MAXFLAVOR] = { - [0] = &svcauth_null, - [1] = &svcauth_unix, +static struct auth_ops __rcu *authtab[RPC_AUTH_MAXFLAVOR] = { + [RPC_AUTH_NULL] = (struct auth_ops __force __rcu *)&svcauth_null, + [RPC_AUTH_UNIX] = (struct auth_ops __force __rcu *)&svcauth_unix, }; +static struct auth_ops * +svc_get_auth_ops(rpc_authflavor_t flavor) +{ + struct auth_ops *aops; + + if (flavor >= RPC_AUTH_MAXFLAVOR) + return NULL; + rcu_read_lock(); + aops = rcu_dereference(authtab[flavor]); + if (aops != NULL && !try_module_get(aops->owner)) + aops = NULL; + rcu_read_unlock(); + return aops; +} + +static void +svc_put_auth_ops(struct auth_ops *aops) +{ + module_put(aops->owner); +} + int svc_authenticate(struct svc_rqst *rqstp, __be32 *authp) { @@ -45,14 +65,11 @@ svc_authenticate(struct svc_rqst *rqstp, __be32 *authp) dprintk("svc: svc_authenticate (%d)\n", flavor); - spin_lock(&authtab_lock); - if (flavor >= RPC_AUTH_MAXFLAVOR || !(aops = authtab[flavor]) || - !try_module_get(aops->owner)) { - spin_unlock(&authtab_lock); + aops = svc_get_auth_ops(flavor); + if (aops == NULL) { *authp = rpc_autherr_badcred; return SVC_DENIED; } - spin_unlock(&authtab_lock); rqstp->rq_auth_slack = 0; init_svc_cred(&rqstp->rq_cred); @@ -82,7 +99,7 @@ int svc_authorise(struct svc_rqst *rqstp) if (aops) { rv = aops->release(rqstp); - module_put(aops->owner); + svc_put_auth_ops(aops); } return rv; } @@ -90,13 +107,14 @@ int svc_authorise(struct svc_rqst *rqstp) int svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops) { + struct auth_ops *old; int rv = -EINVAL; - spin_lock(&authtab_lock); - if (flavor < RPC_AUTH_MAXFLAVOR && authtab[flavor] == NULL) { - authtab[flavor] = aops; - rv = 0; + + if (flavor < RPC_AUTH_MAXFLAVOR) { + old = cmpxchg((struct auth_ops ** __force)&authtab[flavor], NULL, aops); + if (old == NULL || old == aops) + rv = 0; } - spin_unlock(&authtab_lock); return rv; } EXPORT_SYMBOL_GPL(svc_auth_register); @@ -104,10 +122,8 @@ EXPORT_SYMBOL_GPL(svc_auth_register); void svc_auth_unregister(rpc_authflavor_t flavor) { - spin_lock(&authtab_lock); if (flavor < RPC_AUTH_MAXFLAVOR) - authtab[flavor] = NULL; - spin_unlock(&authtab_lock); + rcu_assign_pointer(authtab[flavor], NULL); } EXPORT_SYMBOL_GPL(svc_auth_unregister); @@ -127,10 +143,11 @@ static struct hlist_head auth_domain_table[DN_HASHMAX]; static DEFINE_SPINLOCK(auth_domain_lock); static void auth_domain_release(struct kref *kref) + __releases(&auth_domain_lock) { struct auth_domain *dom = container_of(kref, struct auth_domain, ref); - hlist_del(&dom->hash); + hlist_del_rcu(&dom->hash); dom->flavour->domain_release(dom); spin_unlock(&auth_domain_lock); } @@ -159,7 +176,7 @@ auth_domain_lookup(char *name, struct auth_domain *new) } } if (new) - hlist_add_head(&new->hash, head); + hlist_add_head_rcu(&new->hash, head); spin_unlock(&auth_domain_lock); return new; } @@ -167,6 +184,21 @@ EXPORT_SYMBOL_GPL(auth_domain_lookup); struct auth_domain *auth_domain_find(char *name) { - return auth_domain_lookup(name, NULL); + struct auth_domain *hp; + struct hlist_head *head; + + head = &auth_domain_table[hash_str(name, DN_HASHBITS)]; + + rcu_read_lock(); + hlist_for_each_entry_rcu(hp, head, hash) { + if (strcmp(hp->name, name)==0) { + if (!kref_get_unless_zero(&hp->ref)) + hp = NULL; + rcu_read_unlock(); + return hp; + } + } + rcu_read_unlock(); + return NULL; } EXPORT_SYMBOL_GPL(auth_domain_find); |