diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/sunrpc/svc_xprt.c | 16 | ||||
| -rw-r--r-- | net/sunrpc/svcsock.c | 138 |
2 files changed, 79 insertions, 75 deletions
diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c index 6ff5ca71602..31853bfcd88 100644 --- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -70,6 +70,21 @@ void svc_unreg_xprt_class(struct svc_xprt_class *xcl) } EXPORT_SYMBOL_GPL(svc_unreg_xprt_class); +static void svc_xprt_free(struct kref *kref) +{ + struct svc_xprt *xprt = + container_of(kref, struct svc_xprt, xpt_ref); + struct module *owner = xprt->xpt_class->xcl_owner; + xprt->xpt_ops->xpo_free(xprt); + module_put(owner); +} + +void svc_xprt_put(struct svc_xprt *xprt) +{ + kref_put(&xprt->xpt_ref, svc_xprt_free); +} +EXPORT_SYMBOL_GPL(svc_xprt_put); + /* * Called by transport drivers to initialize the transport independent * portion of the transport instance. @@ -79,6 +94,7 @@ void svc_xprt_init(struct svc_xprt_class *xcl, struct svc_xprt *xprt) memset(xprt, 0, sizeof(*xprt)); xprt->xpt_class = xcl; xprt->xpt_ops = xcl->xcl_ops; + kref_init(&xprt->xpt_ref); } EXPORT_SYMBOL_GPL(svc_xprt_init); diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index e6bb1b0563e..db589d18717 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -66,8 +66,8 @@ * after a clear, the socket must be read/accepted * if this succeeds, it must be set again. * SK_CLOSE can set at any time. It is never cleared. - * sk_inuse contains a bias of '1' until SK_DEAD is set. - * so when sk_inuse hits zero, we know the socket is dead + * xpt_ref contains a bias of '1' until SK_DEAD is set. + * so when xprt_ref hits zero, we know the transport is dead * and no-one is using it. * SK_DEAD can only be set while SK_BUSY is held which ensures * no other thread will be using the socket or will try to @@ -285,7 +285,7 @@ svc_sock_enqueue(struct svc_sock *svsk) "svc_sock_enqueue: server %p, rq_sock=%p!\n", rqstp, rqstp->rq_sock); rqstp->rq_sock = svsk; - atomic_inc(&svsk->sk_inuse); + svc_xprt_get(&svsk->sk_xprt); rqstp->rq_reserved = serv->sv_max_mesg; atomic_add(rqstp->rq_reserved, &svsk->sk_reserved); BUG_ON(svsk->sk_pool != pool); @@ -316,7 +316,7 @@ svc_sock_dequeue(struct svc_pool *pool) list_del_init(&svsk->sk_ready); dprintk("svc: socket %p dequeued, inuse=%d\n", - svsk->sk_sk, atomic_read(&svsk->sk_inuse)); + svsk->sk_sk, atomic_read(&svsk->sk_xprt.xpt_ref.refcount)); return svsk; } @@ -359,19 +359,6 @@ void svc_reserve(struct svc_rqst *rqstp, int space) } } -/* - * Release a socket after use. - */ -static inline void -svc_sock_put(struct svc_sock *svsk) -{ - if (atomic_dec_and_test(&svsk->sk_inuse)) { - BUG_ON(!test_bit(SK_DEAD, &svsk->sk_flags)); - module_put(svsk->sk_xprt.xpt_class->xcl_owner); - svsk->sk_xprt.xpt_ops->xpo_free(&svsk->sk_xprt); - } -} - static void svc_sock_release(struct svc_rqst *rqstp) { @@ -398,7 +385,7 @@ svc_sock_release(struct svc_rqst *rqstp) svc_reserve(rqstp, 0); rqstp->rq_sock = NULL; - svc_sock_put(svsk); + svc_xprt_put(&svsk->sk_xprt); } /* @@ -1128,50 +1115,6 @@ failed: } /* - * Make sure that we don't have too many active connections. If we - * have, something must be dropped. - * - * There's no point in trying to do random drop here for DoS - * prevention. The NFS clients does 1 reconnect in 15 seconds. An - * attacker can easily beat that. - * - * The only somewhat efficient mechanism would be if drop old - * connections from the same IP first. But right now we don't even - * record the client IP in svc_sock. - */ -static void svc_check_conn_limits(struct svc_serv *serv) -{ - if (serv->sv_tmpcnt > (serv->sv_nrthreads+3)*20) { - struct svc_sock *svsk = NULL; - spin_lock_bh(&serv->sv_lock); - if (!list_empty(&serv->sv_tempsocks)) { - if (net_ratelimit()) { - /* Try to help the admin */ - printk(KERN_NOTICE "%s: too many open TCP " - "sockets, consider increasing the " - "number of nfsd threads\n", - serv->sv_name); - } - /* - * Always select the oldest socket. It's not fair, - * but so is life - */ - svsk = list_entry(serv->sv_tempsocks.prev, - struct svc_sock, - sk_list); - set_bit(SK_CLOSE, &svsk->sk_flags); - atomic_inc(&svsk->sk_inuse); - } - spin_unlock_bh(&serv->sv_lock); - - if (svsk) { - svc_sock_enqueue(svsk); - svc_sock_put(svsk); - } - } -} - -/* * Receive data from a TCP socket. */ static int @@ -1497,6 +1440,50 @@ svc_sock_update_bufs(struct svc_serv *serv) } /* + * Make sure that we don't have too many active connections. If we + * have, something must be dropped. + * + * There's no point in trying to do random drop here for DoS + * prevention. The NFS clients does 1 reconnect in 15 seconds. An + * attacker can easily beat that. + * + * The only somewhat efficient mechanism would be if drop old + * connections from the same IP first. But right now we don't even + * record the client IP in svc_sock. + */ +static void svc_check_conn_limits(struct svc_serv *serv) +{ + if (serv->sv_tmpcnt > (serv->sv_nrthreads+3)*20) { + struct svc_sock *svsk = NULL; + spin_lock_bh(&serv->sv_lock); + if (!list_empty(&serv->sv_tempsocks)) { + if (net_ratelimit()) { + /* Try to help the admin */ + printk(KERN_NOTICE "%s: too many open TCP " + "sockets, consider increasing the " + "number of nfsd threads\n", + serv->sv_name); + } + /* + * Always select the oldest socket. It's not fair, + * but so is life + */ + svsk = list_entry(serv->sv_tempsocks.prev, + struct svc_sock, + sk_list); + set_bit(SK_CLOSE, &svsk->sk_flags); + svc_xprt_get(&svsk->sk_xprt); + } + spin_unlock_bh(&serv->sv_lock); + + if (svsk) { + svc_sock_enqueue(svsk); + svc_xprt_put(&svsk->sk_xprt); + } + } +} + +/* * Receive the next request on any socket. This code is carefully * organised not to touch any cachelines in the shared svc_serv * structure, only cachelines in the local svc_pool. @@ -1556,7 +1543,7 @@ svc_recv(struct svc_rqst *rqstp, long timeout) spin_lock_bh(&pool->sp_lock); if ((svsk = svc_sock_dequeue(pool)) != NULL) { rqstp->rq_sock = svsk; - atomic_inc(&svsk->sk_inuse); + svc_xprt_get(&svsk->sk_xprt); rqstp->rq_reserved = serv->sv_max_mesg; atomic_add(rqstp->rq_reserved, &svsk->sk_reserved); } else { @@ -1605,7 +1592,8 @@ svc_recv(struct svc_rqst *rqstp, long timeout) svc_sock_received(svsk); } else { dprintk("svc: server %p, pool %u, socket %p, inuse=%d\n", - rqstp, pool->sp_id, svsk, atomic_read(&svsk->sk_inuse)); + rqstp, pool->sp_id, svsk, + atomic_read(&svsk->sk_xprt.xpt_ref.refcount)); len = svsk->sk_xprt.xpt_ops->xpo_recvfrom(rqstp); dprintk("svc: got len=%d\n", len); } @@ -1702,9 +1690,10 @@ svc_age_temp_sockets(unsigned long closure) if (!test_and_set_bit(SK_OLD, &svsk->sk_flags)) continue; - if (atomic_read(&svsk->sk_inuse) > 1 || test_bit(SK_BUSY, &svsk->sk_flags)) + if (atomic_read(&svsk->sk_xprt.xpt_ref.refcount) > 1 + || test_bit(SK_BUSY, &svsk->sk_flags)) continue; - atomic_inc(&svsk->sk_inuse); + svc_xprt_get(&svsk->sk_xprt); list_move(le, &to_be_aged); set_bit(SK_CLOSE, &svsk->sk_flags); set_bit(SK_DETACHED, &svsk->sk_flags); @@ -1722,7 +1711,7 @@ svc_age_temp_sockets(unsigned long closure) /* a thread will dequeue and close it soon */ svc_sock_enqueue(svsk); - svc_sock_put(svsk); + svc_xprt_put(&svsk->sk_xprt); } mod_timer(&serv->sv_temptimer, jiffies + svc_conn_age_period * HZ); @@ -1767,7 +1756,6 @@ static struct svc_sock *svc_setup_socket(struct svc_serv *serv, svsk->sk_odata = inet->sk_data_ready; svsk->sk_owspace = inet->sk_write_space; svsk->sk_server = serv; - atomic_set(&svsk->sk_inuse, 1); svsk->sk_lastrecv = get_seconds(); spin_lock_init(&svsk->sk_lock); INIT_LIST_HEAD(&svsk->sk_deferred); @@ -1953,10 +1941,10 @@ svc_delete_socket(struct svc_sock *svsk) * is about to be destroyed (in svc_destroy). */ if (!test_and_set_bit(SK_DEAD, &svsk->sk_flags)) { - BUG_ON(atomic_read(&svsk->sk_inuse)<2); - atomic_dec(&svsk->sk_inuse); + BUG_ON(atomic_read(&svsk->sk_xprt.xpt_ref.refcount) < 2); if (test_bit(SK_TEMP, &svsk->sk_flags)) serv->sv_tmpcnt--; + svc_xprt_put(&svsk->sk_xprt); } spin_unlock_bh(&serv->sv_lock); @@ -1969,10 +1957,10 @@ static void svc_close_socket(struct svc_sock *svsk) /* someone else will have to effect the close */ return; - atomic_inc(&svsk->sk_inuse); + svc_xprt_get(&svsk->sk_xprt); svc_delete_socket(svsk); clear_bit(SK_BUSY, &svsk->sk_flags); - svc_sock_put(svsk); + svc_xprt_put(&svsk->sk_xprt); } void svc_force_close_socket(struct svc_sock *svsk) @@ -1998,7 +1986,7 @@ static void svc_revisit(struct cache_deferred_req *dreq, int too_many) struct svc_sock *svsk; if (too_many) { - svc_sock_put(dr->svsk); + svc_xprt_put(&dr->svsk->sk_xprt); kfree(dr); return; } @@ -2010,7 +1998,7 @@ static void svc_revisit(struct cache_deferred_req *dreq, int too_many) spin_unlock(&svsk->sk_lock); set_bit(SK_DEFERRED, &svsk->sk_flags); svc_sock_enqueue(svsk); - svc_sock_put(svsk); + svc_xprt_put(&svsk->sk_xprt); } static struct cache_deferred_req * @@ -2040,7 +2028,7 @@ svc_defer(struct cache_req *req) dr->argslen = rqstp->rq_arg.len >> 2; memcpy(dr->args, rqstp->rq_arg.head[0].iov_base-skip, dr->argslen<<2); } - atomic_inc(&rqstp->rq_sock->sk_inuse); + svc_xprt_get(rqstp->rq_xprt); dr->svsk = rqstp->rq_sock; dr->handle.revisit = svc_revisit; |