net: Remove CONFIG_KMOD from net/ (towards removing CONFIG_KMOD entirely)
[linux-2.6.git] / net / sunrpc / auth.c
index ad7bde2..436bf1b 100644 (file)
@@ -11,6 +11,7 @@
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/errno.h>
+#include <linux/hash.h>
 #include <linux/sunrpc/clnt.h>
 #include <linux/spinlock.h>
 
@@ -26,6 +27,7 @@ static const struct rpc_authops *auth_flavors[RPC_AUTH_MAXFLAVOR] = {
 };
 
 static LIST_HEAD(cred_unused);
+static unsigned long number_cred_unused;
 
 static u32
 pseudoflavor_to_flavor(u32 flavor) {
@@ -50,6 +52,7 @@ rpcauth_register(const struct rpc_authops *ops)
        spin_unlock(&rpc_authflavor_lock);
        return ret;
 }
+EXPORT_SYMBOL_GPL(rpcauth_register);
 
 int
 rpcauth_unregister(const struct rpc_authops *ops)
@@ -67,6 +70,7 @@ rpcauth_unregister(const struct rpc_authops *ops)
        spin_unlock(&rpc_authflavor_lock);
        return ret;
 }
+EXPORT_SYMBOL_GPL(rpcauth_unregister);
 
 struct rpc_auth *
 rpcauth_create(rpc_authflavor_t pseudoflavor, struct rpc_clnt *clnt)
@@ -79,10 +83,8 @@ rpcauth_create(rpc_authflavor_t pseudoflavor, struct rpc_clnt *clnt)
        if (flavor >= RPC_AUTH_MAXFLAVOR)
                goto out;
 
-#ifdef CONFIG_KMOD
        if ((ops = auth_flavors[flavor]) == NULL)
                request_module("rpc-auth-%u", flavor);
-#endif
        spin_lock(&rpc_authflavor_lock);
        ops = auth_flavors[flavor];
        if (ops == NULL || !try_module_get(ops->owner)) {
@@ -101,6 +103,7 @@ rpcauth_create(rpc_authflavor_t pseudoflavor, struct rpc_clnt *clnt)
 out:
        return auth;
 }
+EXPORT_SYMBOL_GPL(rpcauth_create);
 
 void
 rpcauth_release(struct rpc_auth *auth)
@@ -120,11 +123,23 @@ rpcauth_unhash_cred_locked(struct rpc_cred *cred)
        clear_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags);
 }
 
+static void
+rpcauth_unhash_cred(struct rpc_cred *cred)
+{
+       spinlock_t *cache_lock;
+
+       cache_lock = &cred->cr_auth->au_credcache->lock;
+       spin_lock(cache_lock);
+       if (atomic_read(&cred->cr_count) == 0)
+               rpcauth_unhash_cred_locked(cred);
+       spin_unlock(cache_lock);
+}
+
 /*
  * Initialize RPC credential cache
  */
 int
-rpcauth_init_credcache(struct rpc_auth *auth, unsigned long expire)
+rpcauth_init_credcache(struct rpc_auth *auth)
 {
        struct rpc_cred_cache *new;
        int i;
@@ -134,11 +149,11 @@ rpcauth_init_credcache(struct rpc_auth *auth, unsigned long expire)
                return -ENOMEM;
        for (i = 0; i < RPC_CREDCACHE_NR; i++)
                INIT_HLIST_HEAD(&new->hashtable[i]);
-       new->expire = expire;
-       new->nextgc = jiffies + (expire >> 1);
+       spin_lock_init(&new->lock);
        auth->au_credcache = new;
        return 0;
 }
+EXPORT_SYMBOL_GPL(rpcauth_init_credcache);
 
 /*
  * Destroy a list of credentials
@@ -168,15 +183,21 @@ rpcauth_clear_credcache(struct rpc_cred_cache *cache)
        int             i;
 
        spin_lock(&rpc_credcache_lock);
+       spin_lock(&cache->lock);
        for (i = 0; i < RPC_CREDCACHE_NR; i++) {
                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);
+                       if (!list_empty(&cred->cr_lru)) {
+                               list_del(&cred->cr_lru);
+                               number_cred_unused--;
+                       }
+                       list_add_tail(&cred->cr_lru, &free);
                        rpcauth_unhash_cred_locked(cred);
                }
        }
+       spin_unlock(&cache->lock);
        spin_unlock(&rpc_credcache_lock);
        rpcauth_destroy_credlist(&free);
 }
@@ -195,41 +216,63 @@ rpcauth_destroy_credcache(struct rpc_auth *auth)
                kfree(cache);
        }
 }
+EXPORT_SYMBOL_GPL(rpcauth_destroy_credcache);
+
+
+#define RPC_AUTH_EXPIRY_MORATORIUM (60 * HZ)
 
 /*
  * Remove stale credentials. Avoid sleeping inside the loop.
  */
-static void
-rpcauth_prune_expired(struct list_head *free)
+static int
+rpcauth_prune_expired(struct list_head *free, int nr_to_scan)
 {
+       spinlock_t *cache_lock;
        struct rpc_cred *cred;
+       unsigned long expired = jiffies - RPC_AUTH_EXPIRY_MORATORIUM;
 
        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);
+               number_cred_unused--;
                if (atomic_read(&cred->cr_count) != 0)
                        continue;
-               get_rpccred(cred);
-               list_add_tail(&cred->cr_lru, free);
-               rpcauth_unhash_cred_locked(cred);
+               /* Enforce a 5 second garbage collection moratorium */
+               if (time_in_range(cred->cr_expire, expired, jiffies) &&
+                   test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0)
+                       continue;
+               cache_lock = &cred->cr_auth->au_credcache->lock;
+               spin_lock(cache_lock);
+               if (atomic_read(&cred->cr_count) == 0) {
+                       get_rpccred(cred);
+                       list_add_tail(&cred->cr_lru, free);
+                       rpcauth_unhash_cred_locked(cred);
+                       nr_to_scan--;
+               }
+               spin_unlock(cache_lock);
+               if (nr_to_scan == 0)
+                       break;
        }
+       return nr_to_scan;
 }
 
 /*
- * Run garbage collector.
+ * Run memory cache shrinker.
  */
-static void
-rpcauth_gc_credcache(struct rpc_cred_cache *cache, struct list_head *free)
+static int
+rpcauth_cache_shrinker(int nr_to_scan, gfp_t gfp_mask)
 {
-       if (list_empty(&cred_unused) || time_before(jiffies, cache->nextgc))
-               return;
+       LIST_HEAD(free);
+       int res;
+
+       if (list_empty(&cred_unused))
+               return 0;
        spin_lock(&rpc_credcache_lock);
-       cache->nextgc = jiffies + cache->expire;
-       rpcauth_prune_expired(free);
+       nr_to_scan = rpcauth_prune_expired(&free, nr_to_scan);
+       res = (number_cred_unused / 100) * sysctl_vfs_cache_pressure;
        spin_unlock(&rpc_credcache_lock);
+       rpcauth_destroy_credlist(&free);
+       return res;
 }
 
 /*
@@ -244,30 +287,27 @@ rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred,
        struct hlist_node *pos;
        struct rpc_cred *cred = NULL,
                        *entry, *new;
-       int             nr = 0;
+       unsigned int nr;
 
-       if (!(flags & RPCAUTH_LOOKUP_ROOTCREDS))
-               nr = acred->uid & RPC_CREDCACHE_MASK;
+       nr = hash_long(acred->uid, RPC_CREDCACHE_HASHBITS);
 
        rcu_read_lock();
        hlist_for_each_entry_rcu(entry, pos, &cache->hashtable[nr], cr_hash) {
                if (!entry->cr_ops->crmatch(acred, entry, flags))
                        continue;
-               spin_lock(&rpc_credcache_lock);
+               spin_lock(&cache->lock);
                if (test_bit(RPCAUTH_CRED_HASHED, &entry->cr_flags) == 0) {
-                       spin_unlock(&rpc_credcache_lock);
+                       spin_unlock(&cache->lock);
                        continue;
                }
                cred = get_rpccred(entry);
-               spin_unlock(&rpc_credcache_lock);
+               spin_unlock(&cache->lock);
                break;
        }
        rcu_read_unlock();
 
-       if (cred != NULL) {
-               rpcauth_gc_credcache(cache, &free);
+       if (cred != NULL)
                goto found;
-       }
 
        new = auth->au_ops->crcreate(auth, acred, flags);
        if (IS_ERR(new)) {
@@ -275,7 +315,7 @@ rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred,
                goto out;
        }
 
-       spin_lock(&rpc_credcache_lock);
+       spin_lock(&cache->lock);
        hlist_for_each_entry(entry, pos, &cache->hashtable[nr], cr_hash) {
                if (!entry->cr_ops->crmatch(acred, entry, flags))
                        continue;
@@ -288,9 +328,7 @@ rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred,
                hlist_add_head_rcu(&cred->cr_hash, &cache->hashtable[nr]);
        } else
                list_add_tail(&new->cr_lru, &free);
-       rpcauth_prune_expired(&free);
-       cache->nextgc = jiffies + cache->expire;
-       spin_unlock(&rpc_credcache_lock);
+       spin_unlock(&cache->lock);
 found:
        if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags)
                        && cred->cr_ops->cr_init != NULL
@@ -305,6 +343,7 @@ found:
 out:
        return cred;
 }
+EXPORT_SYMBOL_GPL(rpcauth_lookup_credcache);
 
 struct rpc_cred *
 rpcauth_lookupcred(struct rpc_auth *auth, int flags)
@@ -339,42 +378,60 @@ rpcauth_init_cred(struct rpc_cred *cred, const struct auth_cred *acred,
 #endif
        cred->cr_uid = acred->uid;
 }
-EXPORT_SYMBOL(rpcauth_init_cred);
+EXPORT_SYMBOL_GPL(rpcauth_init_cred);
 
-struct rpc_cred *
-rpcauth_bindcred(struct rpc_task *task)
+void
+rpcauth_generic_bind_cred(struct rpc_task *task, struct rpc_cred *cred)
 {
-       struct rpc_auth *auth = task->tk_auth;
+       task->tk_msg.rpc_cred = get_rpccred(cred);
+       dprintk("RPC: %5u holding %s cred %p\n", task->tk_pid,
+                       cred->cr_auth->au_ops->au_name, cred);
+}
+EXPORT_SYMBOL_GPL(rpcauth_generic_bind_cred);
+
+static void
+rpcauth_bind_root_cred(struct rpc_task *task)
+{
+       struct rpc_auth *auth = task->tk_client->cl_auth;
        struct auth_cred acred = {
-               .uid = current->fsuid,
-               .gid = current->fsgid,
-               .group_info = current->group_info,
+               .uid = 0,
+               .gid = 0,
        };
        struct rpc_cred *ret;
-       int flags = 0;
 
        dprintk("RPC: %5u looking up %s cred\n",
-               task->tk_pid, task->tk_auth->au_ops->au_name);
-       get_group_info(acred.group_info);
-       if (task->tk_flags & RPC_TASK_ROOTCREDS)
-               flags |= RPCAUTH_LOOKUP_ROOTCREDS;
-       ret = auth->au_ops->lookup_cred(auth, &acred, flags);
+               task->tk_pid, task->tk_client->cl_auth->au_ops->au_name);
+       ret = auth->au_ops->lookup_cred(auth, &acred, 0);
+       if (!IS_ERR(ret))
+               task->tk_msg.rpc_cred = ret;
+       else
+               task->tk_status = PTR_ERR(ret);
+}
+
+static void
+rpcauth_bind_new_cred(struct rpc_task *task)
+{
+       struct rpc_auth *auth = task->tk_client->cl_auth;
+       struct rpc_cred *ret;
+
+       dprintk("RPC: %5u looking up %s cred\n",
+               task->tk_pid, auth->au_ops->au_name);
+       ret = rpcauth_lookupcred(auth, 0);
        if (!IS_ERR(ret))
                task->tk_msg.rpc_cred = ret;
        else
                task->tk_status = PTR_ERR(ret);
-       put_group_info(acred.group_info);
-       return ret;
 }
 
 void
-rpcauth_holdcred(struct rpc_task *task)
+rpcauth_bindcred(struct rpc_task *task, struct rpc_cred *cred, int flags)
 {
-       dprintk("RPC: %5u holding %s cred %p\n",
-               task->tk_pid, task->tk_auth->au_ops->au_name,
-               task->tk_msg.rpc_cred);
-       if (task->tk_msg.rpc_cred)
-               get_rpccred(task->tk_msg.rpc_cred);
+       if (cred != NULL)
+               cred->cr_ops->crbind(task, cred);
+       else if (flags & RPC_TASK_ROOTCREDS)
+               rpcauth_bind_root_cred(task);
+       else
+               rpcauth_bind_new_cred(task);
 }
 
 void
@@ -390,13 +447,16 @@ put_rpccred(struct rpc_cred *cred)
 need_lock:
        if (!atomic_dec_and_lock(&cred->cr_count, &rpc_credcache_lock))
                return;
-       if (!list_empty(&cred->cr_lru))
+       if (!list_empty(&cred->cr_lru)) {
+               number_cred_unused--;
                list_del_init(&cred->cr_lru);
+       }
        if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0)
-               rpcauth_unhash_cred_locked(cred);
+               rpcauth_unhash_cred(cred);
        else if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0) {
                cred->cr_expire = jiffies;
                list_add_tail(&cred->cr_lru, &cred_unused);
+               number_cred_unused++;
                spin_unlock(&rpc_credcache_lock);
                return;
        }
@@ -404,6 +464,7 @@ need_lock:
 out_destroy:
        cred->cr_ops->crdestroy(cred);
 }
+EXPORT_SYMBOL_GPL(put_rpccred);
 
 void
 rpcauth_unbindcred(struct rpc_task *task)
@@ -411,7 +472,7 @@ rpcauth_unbindcred(struct rpc_task *task)
        struct rpc_cred *cred = task->tk_msg.rpc_cred;
 
        dprintk("RPC: %5u releasing %s cred %p\n",
-               task->tk_pid, task->tk_auth->au_ops->au_name, cred);
+               task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
 
        put_rpccred(cred);
        task->tk_msg.rpc_cred = NULL;
@@ -423,7 +484,7 @@ rpcauth_marshcred(struct rpc_task *task, __be32 *p)
        struct rpc_cred *cred = task->tk_msg.rpc_cred;
 
        dprintk("RPC: %5u marshaling %s cred %p\n",
-               task->tk_pid, task->tk_auth->au_ops->au_name, cred);
+               task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
 
        return cred->cr_ops->crmarshal(task, p);
 }
@@ -434,7 +495,7 @@ rpcauth_checkverf(struct rpc_task *task, __be32 *p)
        struct rpc_cred *cred = task->tk_msg.rpc_cred;
 
        dprintk("RPC: %5u validating %s cred %p\n",
-               task->tk_pid, task->tk_auth->au_ops->au_name, cred);
+               task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
 
        return cred->cr_ops->crvalidate(task, p);
 }
@@ -450,7 +511,7 @@ rpcauth_wrap_req(struct rpc_task *task, kxdrproc_t encode, void *rqstp,
        if (cred->cr_ops->crwrap_req)
                return cred->cr_ops->crwrap_req(task, encode, rqstp, data, obj);
        /* By default, we encode the arguments normally. */
-       return encode(rqstp, data, obj);
+       return rpc_call_xdrproc(encode, rqstp, data, obj);
 }
 
 int
@@ -465,7 +526,7 @@ rpcauth_unwrap_resp(struct rpc_task *task, kxdrproc_t decode, void *rqstp,
                return cred->cr_ops->crunwrap_resp(task, decode, rqstp,
                                                   data, obj);
        /* By default, we decode the arguments normally. */
-       return decode(rqstp, data, obj);
+       return rpc_call_xdrproc(decode, rqstp, data, obj);
 }
 
 int
@@ -475,7 +536,7 @@ rpcauth_refreshcred(struct rpc_task *task)
        int err;
 
        dprintk("RPC: %5u refreshing %s cred %p\n",
-               task->tk_pid, task->tk_auth->au_ops->au_name, cred);
+               task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
 
        err = cred->cr_ops->crrefresh(task);
        if (err < 0)
@@ -489,7 +550,7 @@ rpcauth_invalcred(struct rpc_task *task)
        struct rpc_cred *cred = task->tk_msg.rpc_cred;
 
        dprintk("RPC: %5u invalidating %s cred %p\n",
-               task->tk_pid, task->tk_auth->au_ops->au_name, cred);
+               task->tk_pid, cred->cr_auth->au_ops->au_name, cred);
        if (cred)
                clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
 }
@@ -502,3 +563,20 @@ rpcauth_uptodatecred(struct rpc_task *task)
        return cred == NULL ||
                test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0;
 }
+
+static struct shrinker rpc_cred_shrinker = {
+       .shrink = rpcauth_cache_shrinker,
+       .seeks = DEFAULT_SEEKS,
+};
+
+void __init rpcauth_init_module(void)
+{
+       rpc_init_authunix();
+       rpc_init_generic_auth();
+       register_shrinker(&rpc_cred_shrinker);
+}
+
+void __exit rpcauth_remove_module(void)
+{
+       unregister_shrinker(&rpc_cred_shrinker);
+}