diff options
Diffstat (limited to 'net/sunrpc/auth.c')
| -rw-r--r-- | net/sunrpc/auth.c | 121 |
1 files changed, 72 insertions, 49 deletions
diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c index 4d7c78b..00f9649 100644 --- a/net/sunrpc/auth.c +++ b/net/sunrpc/auth.c @@ -25,6 +25,8 @@ static const struct rpc_authops *auth_flavors[RPC_AUTH_MAXFLAVOR] = { NULL, /* others can be loadable modules */ }; +static LIST_HEAD(cred_unused); + static u32 pseudoflavor_to_flavor(u32 flavor) { if (flavor >= RPC_AUTH_MAXFLAVOR) @@ -134,13 +136,13 @@ rpcauth_init_credcache(struct rpc_auth *auth, unsigned long expire) * Destroy a list of credentials */ static inline -void rpcauth_destroy_credlist(struct hlist_head *head) +void rpcauth_destroy_credlist(struct list_head *head) { struct rpc_cred *cred; - while (!hlist_empty(head)) { - cred = hlist_entry(head->first, struct rpc_cred, cr_hash); - hlist_del_init(&cred->cr_hash); + while (!list_empty(head)) { + cred = list_entry(head->next, struct rpc_cred, cr_lru); + list_del_init(&cred->cr_lru); put_rpccred(cred); } } @@ -152,17 +154,20 @@ void rpcauth_destroy_credlist(struct hlist_head *head) void rpcauth_clear_credcache(struct rpc_cred_cache *cache) { - HLIST_HEAD(free); - struct hlist_node *pos, *next; + LIST_HEAD(free); + struct hlist_head *head; struct rpc_cred *cred; int i; spin_lock(&rpc_credcache_lock); for (i = 0; i < RPC_CREDCACHE_NR; i++) { - hlist_for_each_safe(pos, next, &cache->hashtable[i]) { - cred = hlist_entry(pos, struct rpc_cred, cr_hash); - __hlist_del(&cred->cr_hash); - hlist_add_head(&cred->cr_hash, &free); + head = &cache->hashtable[i]; + while (!hlist_empty(head)) { + cred = hlist_entry(head->first, struct rpc_cred, cr_hash); + get_rpccred(cred); + list_move_tail(&cred->cr_lru, &free); + smp_wmb(); + hlist_del_init(&cred->cr_hash); } } spin_unlock(&rpc_credcache_lock); @@ -184,38 +189,39 @@ rpcauth_destroy_credcache(struct rpc_auth *auth) } } +/* + * Remove stale credentials. Avoid sleeping inside the loop. + */ static void -rpcauth_prune_expired(struct rpc_auth *auth, struct rpc_cred *cred, struct hlist_head *free) +rpcauth_prune_expired(struct list_head *free) { - if (atomic_read(&cred->cr_count) != 1) - return; - if (time_after(jiffies, cred->cr_expire + auth->au_credcache->expire)) - clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); - if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0) { - __hlist_del(&cred->cr_hash); - hlist_add_head(&cred->cr_hash, free); + struct rpc_cred *cred; + + while (!list_empty(&cred_unused)) { + cred = list_entry(cred_unused.next, struct rpc_cred, cr_lru); + if (time_after(jiffies, cred->cr_expire + + cred->cr_auth->au_credcache->expire)) + break; + list_del_init(&cred->cr_lru); + if (atomic_read(&cred->cr_count) != 0) + continue; + get_rpccred(cred); + list_add_tail(&cred->cr_lru, free); + smp_wmb(); + hlist_del_init(&cred->cr_hash); } } /* - * Remove stale credentials. Avoid sleeping inside the loop. + * Run garbage collector. */ static void -rpcauth_gc_credcache(struct rpc_auth *auth, struct hlist_head *free) +rpcauth_gc_credcache(struct rpc_cred_cache *cache, struct list_head *free) { - struct rpc_cred_cache *cache = auth->au_credcache; - struct hlist_node *pos, *next; - struct rpc_cred *cred; - int i; - - dprintk("RPC: gc'ing RPC credentials for auth %p\n", auth); - for (i = 0; i < RPC_CREDCACHE_NR; i++) { - hlist_for_each_safe(pos, next, &cache->hashtable[i]) { - cred = hlist_entry(pos, struct rpc_cred, cr_hash); - rpcauth_prune_expired(auth, cred, free); - } - } + if (time_before(jiffies, cache->nextgc)) + return; cache->nextgc = jiffies + cache->expire; + rpcauth_prune_expired(free); } /* @@ -225,39 +231,35 @@ struct rpc_cred * rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred, int flags) { + LIST_HEAD(free); struct rpc_cred_cache *cache = auth->au_credcache; - HLIST_HEAD(free); - struct hlist_node *pos, *next; + struct hlist_node *pos; struct rpc_cred *new = NULL, - *cred = NULL; + *cred = NULL, + *entry; int nr = 0; if (!(flags & RPCAUTH_LOOKUP_ROOTCREDS)) nr = acred->uid & RPC_CREDCACHE_MASK; retry: spin_lock(&rpc_credcache_lock); - if (time_before(cache->nextgc, jiffies)) - rpcauth_gc_credcache(auth, &free); - hlist_for_each_safe(pos, next, &cache->hashtable[nr]) { - struct rpc_cred *entry; - entry = hlist_entry(pos, struct rpc_cred, cr_hash); - if (entry->cr_ops->crmatch(acred, entry, flags)) { - hlist_del(&entry->cr_hash); - cred = entry; - break; - } - rpcauth_prune_expired(auth, entry, &free); + hlist_for_each_entry(entry, pos, &cache->hashtable[nr], cr_hash) { + if (!entry->cr_ops->crmatch(acred, entry, flags)) + continue; + cred = get_rpccred(entry); + hlist_del(&entry->cr_hash); + break; } if (new) { if (cred) - hlist_add_head(&new->cr_hash, &free); + list_add_tail(&new->cr_lru, &free); else cred = new; } if (cred) { hlist_add_head(&cred->cr_hash, &cache->hashtable[nr]); - get_rpccred(cred); } + rpcauth_gc_credcache(cache, &free); spin_unlock(&rpc_credcache_lock); rpcauth_destroy_credlist(&free); @@ -303,6 +305,7 @@ rpcauth_init_cred(struct rpc_cred *cred, const struct auth_cred *acred, struct rpc_auth *auth, const struct rpc_credops *ops) { INIT_HLIST_NODE(&cred->cr_hash); + INIT_LIST_HEAD(&cred->cr_lru); atomic_set(&cred->cr_count, 1); cred->cr_auth = auth; cred->cr_ops = ops; @@ -353,9 +356,29 @@ rpcauth_holdcred(struct rpc_task *task) void put_rpccred(struct rpc_cred *cred) { - cred->cr_expire = jiffies; + /* Fast path for unhashed credentials */ + if (!hlist_unhashed(&cred->cr_hash)) + goto need_lock; + if (!atomic_dec_and_test(&cred->cr_count)) return; + goto out_destroy; + +need_lock: + if (!atomic_dec_and_lock(&cred->cr_count, &rpc_credcache_lock)) + return; + if (!list_empty(&cred->cr_lru)) + list_del_init(&cred->cr_lru); + if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0) + hlist_del(&cred->cr_hash); + else if (!hlist_unhashed(&cred->cr_hash)) { + cred->cr_expire = jiffies; + list_add_tail(&cred->cr_lru, &cred_unused); + spin_unlock(&rpc_credcache_lock); + return; + } + spin_unlock(&rpc_credcache_lock); +out_destroy: cred->cr_ops->crdestroy(cred); } |
