diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/sunrpc/svc_xprt.c | 753 | ||||
| -rw-r--r-- | net/sunrpc/svcsock.c | 834 |
2 files changed, 777 insertions, 810 deletions
diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c index 271467c5138..23165aef59d 100644 --- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -35,10 +35,53 @@ #define RPCDBG_FACILITY RPCDBG_SVCXPRT +static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt); +static int svc_deferred_recv(struct svc_rqst *rqstp); +static struct cache_deferred_req *svc_defer(struct cache_req *req); +static void svc_age_temp_xprts(unsigned long closure); + +/* apparently the "standard" is that clients close + * idle connections after 5 minutes, servers after + * 6 minutes + * http://www.connectathon.org/talks96/nfstcp.pdf + */ +static int svc_conn_age_period = 6*60; + /* List of registered transport classes */ static DEFINE_SPINLOCK(svc_xprt_class_lock); static LIST_HEAD(svc_xprt_class_list); +/* SMP locking strategy: + * + * svc_pool->sp_lock protects most of the fields of that pool. + * svc_serv->sv_lock protects sv_tempsocks, sv_permsocks, sv_tmpcnt. + * when both need to be taken (rare), svc_serv->sv_lock is first. + * BKL protects svc_serv->sv_nrthread. + * svc_sock->sk_lock protects the svc_sock->sk_deferred list + * and the ->sk_info_authunix cache. + * + * The XPT_BUSY bit in xprt->xpt_flags prevents a transport being + * enqueued multiply. During normal transport processing this bit + * is set by svc_xprt_enqueue and cleared by svc_xprt_received. + * Providers should not manipulate this bit directly. + * + * Some flags can be set to certain values at any time + * providing that certain rules are followed: + * + * XPT_CONN, XPT_DATA: + * - Can be set or cleared at any time. + * - After a set, svc_xprt_enqueue must be called to enqueue + * the transport for processing. + * - After a clear, the transport must be read/accepted. + * If this succeeds, it must be set again. + * XPT_CLOSE: + * - Can set at any time. It is never cleared. + * XPT_DEAD: + * - Can only be set while XPT_BUSY is held which ensures + * that no other thread will be using the transport or will + * try to set XPT_DEAD. + */ + int svc_reg_xprt_class(struct svc_xprt_class *xcl) { struct svc_xprt_class *cl; @@ -178,3 +221,713 @@ void svc_xprt_copy_addrs(struct svc_rqst *rqstp, struct svc_xprt *xprt) } EXPORT_SYMBOL_GPL(svc_xprt_copy_addrs); +/** + * svc_print_addr - Format rq_addr field for printing + * @rqstp: svc_rqst struct containing address to print + * @buf: target buffer for formatted address + * @len: length of target buffer + * + */ +char *svc_print_addr(struct svc_rqst *rqstp, char *buf, size_t len) +{ + return __svc_print_addr(svc_addr(rqstp), buf, len); +} +EXPORT_SYMBOL_GPL(svc_print_addr); + +/* + * Queue up an idle server thread. Must have pool->sp_lock held. + * Note: this is really a stack rather than a queue, so that we only + * use as many different threads as we need, and the rest don't pollute + * the cache. + */ +static void svc_thread_enqueue(struct svc_pool *pool, struct svc_rqst *rqstp) +{ + list_add(&rqstp->rq_list, &pool->sp_threads); +} + +/* + * Dequeue an nfsd thread. Must have pool->sp_lock held. + */ +static void svc_thread_dequeue(struct svc_pool *pool, struct svc_rqst *rqstp) +{ + list_del(&rqstp->rq_list); +} + +/* + * Queue up a transport with data pending. If there are idle nfsd + * processes, wake 'em up. + * + */ +void svc_xprt_enqueue(struct svc_xprt *xprt) +{ + struct svc_serv *serv = xprt->xpt_server; + struct svc_pool *pool; + struct svc_rqst *rqstp; + int cpu; + + if (!(xprt->xpt_flags & + ((1<<XPT_CONN)|(1<<XPT_DATA)|(1<<XPT_CLOSE)|(1<<XPT_DEFERRED)))) + return; + if (test_bit(XPT_DEAD, &xprt->xpt_flags)) + return; + + cpu = get_cpu(); + pool = svc_pool_for_cpu(xprt->xpt_server, cpu); + put_cpu(); + + spin_lock_bh(&pool->sp_lock); + + if (!list_empty(&pool->sp_threads) && + !list_empty(&pool->sp_sockets)) + printk(KERN_ERR + "svc_xprt_enqueue: " + "threads and transports both waiting??\n"); + + if (test_bit(XPT_DEAD, &xprt->xpt_flags)) { + /* Don't enqueue dead transports */ + dprintk("svc: transport %p is dead, not enqueued\n", xprt); + goto out_unlock; + } + + /* Mark transport as busy. It will remain in this state until + * the provider calls svc_xprt_received. We update XPT_BUSY + * atomically because it also guards against trying to enqueue + * the transport twice. + */ + if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags)) { + /* Don't enqueue transport while already enqueued */ + dprintk("svc: transport %p busy, not enqueued\n", xprt); + goto out_unlock; + } + BUG_ON(xprt->xpt_pool != NULL); + xprt->xpt_pool = pool; + + /* Handle pending connection */ + if (test_bit(XPT_CONN, &xprt->xpt_flags)) + goto process; + + /* Handle close in-progress */ + if (test_bit(XPT_CLOSE, &xprt->xpt_flags)) + goto process; + + /* Check if we have space to reply to a request */ + if (!xprt->xpt_ops->xpo_has_wspace(xprt)) { + /* Don't enqueue while not enough space for reply */ + dprintk("svc: no write space, transport %p not enqueued\n", + xprt); + xprt->xpt_pool = NULL; + clear_bit(XPT_BUSY, &xprt->xpt_flags); + goto out_unlock; + } + + process: + if (!list_empty(&pool->sp_threads)) { + rqstp = list_entry(pool->sp_threads.next, + struct svc_rqst, + rq_list); + dprintk("svc: transport %p served by daemon %p\n", + xprt, rqstp); + svc_thread_dequeue(pool, rqstp); + if (rqstp->rq_xprt) + printk(KERN_ERR + "svc_xprt_enqueue: server %p, rq_xprt=%p!\n", + rqstp, rqstp->rq_xprt); + rqstp->rq_xprt = xprt; + svc_xprt_get(xprt); + rqstp->rq_reserved = serv->sv_max_mesg; + atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved); + BUG_ON(xprt->xpt_pool != pool); + wake_up(&rqstp->rq_wait); + } else { + dprintk("svc: transport %p put into queue\n", xprt); + list_add_tail(&xprt->xpt_ready, &pool->sp_sockets); + BUG_ON(xprt->xpt_pool != pool); + } + +out_unlock: + spin_unlock_bh(&pool->sp_lock); +} +EXPORT_SYMBOL_GPL(svc_xprt_enqueue); + +/* + * Dequeue the first transport. Must be called with the pool->sp_lock held. + */ +static struct svc_xprt *svc_xprt_dequeue(struct svc_pool *pool) +{ + struct svc_xprt *xprt; + + if (list_empty(&pool->sp_sockets)) + return NULL; + + xprt = list_entry(pool->sp_sockets.next, + struct svc_xprt, xpt_ready); + list_del_init(&xprt->xpt_ready); + + dprintk("svc: transport %p dequeued, inuse=%d\n", + xprt, atomic_read(&xprt->xpt_ref.refcount)); + + return xprt; +} + +/* + * svc_xprt_received conditionally queues the transport for processing + * by another thread. The caller must hold the XPT_BUSY bit and must + * not thereafter touch transport data. + * + * Note: XPT_DATA only gets cleared when a read-attempt finds no (or + * insufficient) data. + */ +void svc_xprt_received(struct svc_xprt *xprt) +{ + BUG_ON(!test_bit(XPT_BUSY, &xprt->xpt_flags)); + xprt->xpt_pool = NULL; + clear_bit(XPT_BUSY, &xprt->xpt_flags); + svc_xprt_enqueue(xprt); +} +EXPORT_SYMBOL_GPL(svc_xprt_received); + +/** + * svc_reserve - change the space reserved for the reply to a request. + * @rqstp: The request in question + * @space: new max space to reserve + * + * Each request reserves some space on the output queue of the transport + * to make sure the reply fits. This function reduces that reserved + * space to be the amount of space used already, plus @space. + * + */ +void svc_reserve(struct svc_rqst *rqstp, int space) +{ + space += rqstp->rq_res.head[0].iov_len; + + if (space < rqstp->rq_reserved) { + struct svc_xprt *xprt = rqstp->rq_xprt; + atomic_sub((rqstp->rq_reserved - space), &xprt->xpt_reserved); + rqstp->rq_reserved = space; + + svc_xprt_enqueue(xprt); + } +} + +static void svc_xprt_release(struct svc_rqst *rqstp) +{ + struct svc_xprt *xprt = rqstp->rq_xprt; + + rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp); + + svc_free_res_pages(rqstp); + rqstp->rq_res.page_len = 0; + rqstp->rq_res.page_base = 0; + + /* Reset response buffer and release + * the reservation. + * But first, check that enough space was reserved + * for the reply, otherwise we have a bug! + */ + if ((rqstp->rq_res.len) > rqstp->rq_reserved) + printk(KERN_ERR "RPC request reserved %d but used %d\n", + rqstp->rq_reserved, + rqstp->rq_res.len); + + rqstp->rq_res.head[0].iov_len = 0; + svc_reserve(rqstp, 0); + rqstp->rq_xprt = NULL; + + svc_xprt_put(xprt); +} + +/* + * External function to wake up a server waiting for data + * This really only makes sense for services like lockd + * which have exactly one thread anyway. + */ +void svc_wake_up(struct svc_serv *serv) +{ + struct svc_rqst *rqstp; + unsigned int i; + struct svc_pool *pool; + + for (i = 0; i < serv->sv_nrpools; i++) { + pool = &serv->sv_pools[i]; + + spin_lock_bh(&pool->sp_lock); + if (!list_empty(&pool->sp_threads)) { + rqstp = list_entry(pool->sp_threads.next, + struct svc_rqst, + rq_list); + dprintk("svc: daemon %p woken up.\n", rqstp); + /* + svc_thread_dequeue(pool, rqstp); + rqstp->rq_xprt = NULL; + */ + wake_up(&rqstp->rq_wait); + } + spin_unlock_bh(&pool->sp_lock); + } +} + +int svc_port_is_privileged(struct sockaddr *sin) +{ + switch (sin->sa_family) { + case AF_INET: + return ntohs(((struct sockaddr_in *)sin)->sin_port) + < PROT_SOCK; + case AF_INET6: + return ntohs(((struct sockaddr_in6 *)sin)->sin6_port) + < PROT_SOCK; + default: + return 0; + } +} + +/* + * 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_xprt *xprt = 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 " + "connections, consider increasing the " + "number of nfsd threads\n", + serv->sv_name); + } + /* + * Always select the oldest connection. It's not fair, + * but so is life + */ + xprt = list_entry(serv->sv_tempsocks.prev, + struct svc_xprt, + xpt_list); + set_bit(XPT_CLOSE, &xprt->xpt_flags); + svc_xprt_get(xprt); + } + spin_unlock_bh(&serv->sv_lock); + + if (xprt) { + svc_xprt_enqueue(xprt); + svc_xprt_put(xprt); + } + } +} + +/* + * Receive the next request on any transport. This code is carefully + * organised not to touch any cachelines in the shared svc_serv + * structure, only cachelines in the local svc_pool. + */ +int svc_recv(struct svc_rqst *rqstp, long timeout) +{ + struct svc_xprt *xprt = NULL; + struct svc_serv *serv = rqstp->rq_server; + struct svc_pool *pool = rqstp->rq_pool; + int len, i; + int pages; + struct xdr_buf *arg; + DECLARE_WAITQUEUE(wait, current); + + dprintk("svc: server %p waiting for data (to = %ld)\n", + rqstp, timeout); + + if (rqstp->rq_xprt) + printk(KERN_ERR + "svc_recv: service %p, transport not NULL!\n", + rqstp); + if (waitqueue_active(&rqstp->rq_wait)) + printk(KERN_ERR + "svc_recv: service %p, wait queue active!\n", + rqstp); + + /* now allocate needed pages. If we get a failure, sleep briefly */ + pages = (serv->sv_max_mesg + PAGE_SIZE) / PAGE_SIZE; + for (i = 0; i < pages ; i++) + while (rqstp->rq_pages[i] == NULL) { + struct page *p = alloc_page(GFP_KERNEL); + if (!p) { + int j = msecs_to_jiffies(500); + schedule_timeout_uninterruptible(j); + } + rqstp->rq_pages[i] = p; + } + rqstp->rq_pages[i++] = NULL; /* this might be seen in nfs_read_actor */ + BUG_ON(pages >= RPCSVC_MAXPAGES); + + /* Make arg->head point to first page and arg->pages point to rest */ + arg = &rqstp->rq_arg; + arg->head[0].iov_base = page_address(rqstp->rq_pages[0]); + arg->head[0].iov_len = PAGE_SIZE; + arg->pages = rqstp->rq_pages + 1; + arg->page_base = 0; + /* save at least one page for response */ + arg->page_len = (pages-2)*PAGE_SIZE; + arg->len = (pages-1)*PAGE_SIZE; + arg->tail[0].iov_len = 0; + + try_to_freeze(); + cond_resched(); + if (signalled()) + return -EINTR; + + spin_lock_bh(&pool->sp_lock); + xprt = svc_xprt_dequeue(pool); + if (xprt) { + rqstp->rq_xprt = xprt; + svc_xprt_get(xprt); + rqstp->rq_reserved = serv->sv_max_mesg; + atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved); + } else { + /* No data pending. Go to sleep */ + svc_thread_enqueue(pool, rqstp); + + /* + * We have to be able to interrupt this wait + * to bring down the daemons ... + */ + set_current_state(TASK_INTERRUPTIBLE); + add_wait_queue(&rqstp->rq_wait, &wait); + spin_unlock_bh(&pool->sp_lock); + + schedule_timeout(timeout); + + try_to_freeze(); + + spin_lock_bh(&pool->sp_lock); + remove_wait_queue(&rqstp->rq_wait, &wait); + + xprt = rqstp->rq_xprt; + if (!xprt) { + svc_thread_dequeue(pool, rqstp); + spin_unlock_bh(&pool->sp_lock); + dprintk("svc: server %p, no data yet\n", rqstp); + return signalled()? -EINTR : -EAGAIN; + } + } + spin_unlock_bh(&pool->sp_lock); + + len = 0; + if (test_bit(XPT_CLOSE, &xprt->xpt_flags)) { + dprintk("svc_recv: found XPT_CLOSE\n"); + svc_delete_xprt(xprt); + } else if (test_bit(XPT_LISTENER, &xprt->xpt_flags)) { + struct svc_xprt *newxpt; + newxpt = xprt->xpt_ops->xpo_accept(xprt); + if (newxpt) { + /* + * We know this module_get will succeed because the + * listener holds a reference too + */ + __module_get(newxpt->xpt_class->xcl_owner); + svc_check_conn_limits(xprt->xpt_server); + spin_lock_bh(&serv->sv_lock); + set_bit(XPT_TEMP, &newxpt->xpt_flags); + list_add(&newxpt->xpt_list, &serv->sv_tempsocks); + serv->sv_tmpcnt++; + if (serv->sv_temptimer.function == NULL) { + /* setup timer to age temp transports */ + setup_timer(&serv->sv_temptimer, + svc_age_temp_xprts, + (unsigned long)serv); + mod_timer(&serv->sv_temptimer, + jiffies + svc_conn_age_period * HZ); + } + spin_unlock_bh(&serv->sv_lock); + svc_xprt_received(newxpt); + } + svc_xprt_received(xprt); + } else { + dprintk("svc: server %p, pool %u, transport %p, inuse=%d\n", + rqstp, pool->sp_id, xprt, + atomic_read(&xprt->xpt_ref.refcount)); + rqstp->rq_deferred = svc_deferred_dequeue(xprt); + if (rqstp->rq_deferred) { + svc_xprt_received(xprt); + len = svc_deferred_recv(rqstp); + } else + len = xprt->xpt_ops->xpo_recvfrom(rqstp); + dprintk("svc: got len=%d\n", len); + } + + /* No data, incomplete (TCP) read, or accept() */ + if (len == 0 || len == -EAGAIN) { + rqstp->rq_res.len = 0; + svc_xprt_release(rqstp); + return -EAGAIN; + } + clear_bit(XPT_OLD, &xprt->xpt_flags); + + rqstp->rq_secure = svc_port_is_privileged(svc_addr(rqstp)); + rqstp->rq_chandle.defer = svc_defer; + + if (serv->sv_stats) + serv->sv_stats->netcnt++; + return len; +} + +/* + * Drop request + */ +void svc_drop(struct svc_rqst *rqstp) +{ + dprintk("svc: xprt %p dropped request\n", rqstp->rq_xprt); + svc_xprt_release(rqstp); +} + +/* + * Return reply to client. + */ +int svc_send(struct svc_rqst *rqstp) +{ + struct svc_xprt *xprt; + int len; + struct xdr_buf *xb; + + xprt = rqstp->rq_xprt; + if (!xprt) + return -EFAULT; + + /* release the receive skb before sending the reply */ + rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp); + + /* calculate over-all length */ + xb = &rqstp->rq_res; + xb->len = xb->head[0].iov_len + + xb->page_len + + xb->tail[0].iov_len; + + /* Grab mutex to serialize outgoing data. */ + mutex_lock(&xprt->xpt_mutex); + if (test_bit(XPT_DEAD, &xprt->xpt_flags)) + len = -ENOTCONN; + else + len = xprt->xpt_ops->xpo_sendto(rqstp); + mutex_unlock(&xprt->xpt_mutex); + svc_xprt_release(rqstp); + + if (len == -ECONNREFUSED || len == -ENOTCONN || len == -EAGAIN) + return 0; + return len; +} + +/* + * Timer function to close old temporary transports, using + * a mark-and-sweep algorithm. + */ +static void svc_age_temp_xprts(unsigned long closure) +{ + struct svc_serv *serv = (struct svc_serv *)closure; + struct svc_xprt *xprt; + struct list_head *le, *next; + LIST_HEAD(to_be_aged); + + dprintk("svc_age_temp_xprts\n"); + + if (!spin_trylock_bh(&serv->sv_lock)) { + /* busy, try again 1 sec later */ + dprintk("svc_age_temp_xprts: busy\n"); + mod_timer(&serv->sv_temptimer, jiffies + HZ); + return; + } + + list_for_each_safe(le, next, &serv->sv_tempsocks) { + xprt = list_entry(le, struct svc_xprt, xpt_list); + + /* First time through, just mark it OLD. Second time + * through, close it. */ + if (!test_and_set_bit(XPT_OLD, &xprt->xpt_flags)) + continue; + if (atomic_read(&xprt->xpt_ref.refcount) > 1 + || test_bit(XPT_BUSY, &xprt->xpt_flags)) + continue; + svc_xprt_get(xprt); + list_move(le, &to_be_aged); + set_bit(XPT_CLOSE, &xprt->xpt_flags); + set_bit(XPT_DETACHED, &xprt->xpt_flags); + } + spin_unlock_bh(&serv->sv_lock); + + while (!list_empty(&to_be_aged)) { + le = to_be_aged.next; + /* fiddling the xpt_list node is safe 'cos we're XPT_DETACHED */ + list_del_init(le); + xprt = list_entry(le, struct svc_xprt, xpt_list); + + dprintk("queuing xprt %p for closing\n", xprt); + + /* a thread will dequeue and close it soon */ + svc_xprt_enqueue(xprt); + svc_xprt_put(xprt); + } + + mod_timer(&serv->sv_temptimer, jiffies + svc_conn_age_period * HZ); +} + +/* + * Remove a dead transport + */ +void svc_delete_xprt(struct svc_xprt *xprt) +{ + struct svc_serv *serv = xprt->xpt_server; + + dprintk("svc: svc_delete_xprt(%p)\n", xprt); + xprt->xpt_ops->xpo_detach(xprt); + + spin_lock_bh(&serv->sv_lock); + if (!test_and_set_bit(XPT_DETACHED, &xprt->xpt_flags)) + list_del_init(&xprt->xpt_list); + /* + * We used to delete the transport from whichever list + * it's sk_xprt.xpt_ready node was on, but we don't actually + * need to. This is because the only time we're called + * while still attached to a queue, the queue itself + * is about to be destroyed (in svc_destroy). + */ + if (!test_and_set_bit(XPT_DEAD, &xprt->xpt_flags)) { + BUG_ON(atomic_read(&xprt->xpt_ref.refcount) < 2); + if (test_bit(XPT_TEMP, &xprt->xpt_flags)) + serv->sv_tmpcnt--; + svc_xprt_put(xprt); + } + spin_unlock_bh(&serv->sv_lock); +} + +void svc_close_xprt(struct svc_xprt *xprt) +{ + set_bit(XPT_CLOSE, &xprt->xpt_flags); + if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags)) + /* someone else will have to effect the close */ + return; + + svc_xprt_get(xprt); + svc_delete_xprt(xprt); + clear_bit(XPT_BUSY, &xprt->xpt_flags); + svc_xprt_put(xprt); +} + +void svc_close_all(struct list_head *xprt_list) +{ + struct svc_xprt *xprt; + struct svc_xprt *tmp; + + list_for_each_entry_safe(xprt, tmp, xprt_list, xpt_list) { + set_bit(XPT_CLOSE, &xprt->xpt_flags); + if (test_bit(XPT_BUSY, &xprt->xpt_flags)) { + /* Waiting to be processed, but no threads left, + * So just remove it from the waiting list + */ + list_del_init(&xprt->xpt_ready); + clear_bit(XPT_BUSY, &xprt->xpt_flags); + } + svc_close_xprt(xprt); + } +} + +/* + * Handle defer and revisit of requests + */ + +static void svc_revisit(struct cache_deferred_req *dreq, int too_many) +{ + struct svc_deferred_req *dr = + container_of(dreq, struct svc_deferred_req, handle); + struct svc_xprt *xprt = dr->xprt; + + if (too_many) { + svc_xprt_put(xprt); + kfree(dr); + return; + } + dprintk("revisit queued\n"); + dr->xprt = NULL; + spin_lock(&xprt->xpt_lock); + list_add(&dr->handle.recent, &xprt->xpt_deferred); + spin_unlock(&xprt->xpt_lock); + set_bit(XPT_DEFERRED, &xprt->xpt_flags); + svc_xprt_enqueue(xprt); + svc_xprt_put(xprt); +} + +static struct cache_deferred_req *svc_defer(struct cache_req *req) +{ + struct svc_rqst *rqstp = container_of(req, struct svc_rqst, rq_chandle); + int size = sizeof(struct svc_deferred_req) + (rqstp->rq_arg.len); + struct svc_deferred_req *dr; + + if (rqstp->rq_arg.page_len) + return NULL; /* if more than a page, give up FIXME */ + if (rqstp->rq_deferred) { + dr = rqstp->rq_deferred; + rqstp->rq_deferred = NULL; + } else { + int skip = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len; + /* FIXME maybe discard if size too large */ + dr = kmalloc(size, GFP_KERNEL); + if (dr == NULL) + return NULL; + + dr->handle.owner = rqstp->rq_server; + dr->prot = rqstp->rq_prot; + memcpy(&dr->addr, &rqstp->rq_addr, rqstp->rq_addrlen); + dr->addrlen = rqstp->rq_addrlen; + dr->daddr = rqstp->rq_daddr; + dr->argslen = rqstp->rq_arg.len >> 2; + memcpy(dr->args, rqstp->rq_arg.head[0].iov_base-skip, + dr->argslen<<2); + } + svc_xprt_get(rqstp->rq_xprt); + dr->xprt = rqstp->rq_xprt; + + dr->handle.revisit = svc_revisit; + return &dr->handle; +} + +/* + * recv data from a deferred request into an active one + */ +static int svc_deferred_recv(struct svc_rqst *rqstp) +{ + struct svc_deferred_req *dr = rqstp->rq_deferred; + + rqstp->rq_arg.head[0].iov_base = dr->args; + rqstp->rq_arg.head[0].iov_len = dr->argslen<<2; + rqstp->rq_arg.page_len = 0; + rqstp->rq_arg.len = dr->argslen<<2; + rqstp->rq_prot = dr->prot; + memcpy(&rqstp->rq_addr, &dr->addr, dr->addrlen); + rqstp->rq_addrlen = dr->addrlen; + rqstp->rq_daddr = dr->daddr; + rqstp->rq_respages = rqstp->rq_pages; + return dr->argslen<<2; +} + + +static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt) +{ + struct svc_deferred_req *dr = NULL; + + if (!test_bit(XPT_DEFERRED, &xprt->xpt_flags)) + return NULL; + spin_lock(&xprt->xpt_lock); + clear_bit(XPT_DEFERRED, &xprt->xpt_flags); + if (!list_empty(&xprt->xpt_deferred)) { + dr = list_entry(xprt->xpt_deferred.next, + struct svc_deferred_req, + handle.recent); + list_del_init(&dr->handle.recent); + set_bit(XPT_DEFERRED, &xprt->xpt_flags); + } + spin_unlock(&xprt->xpt_lock); + return dr; +} diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index 0814a78ad7a..343a85b700f 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -48,66 +48,24 @@ #include <linux/sunrpc/svcsock.h> #include <linux/sunrpc/stats.h> -/* SMP locking strategy: - * - * svc_pool->sp_lock protects most of the fields of that pool. - * svc_serv->sv_lock protects sv_tempsocks, sv_permsocks, sv_tmpcnt. - * when both need to be taken (rare), svc_serv->sv_lock is first. - * BKL protects svc_serv->sv_nrthread. - * svc_sock->sk_lock protects the svc_sock->sk_deferred list - * and the ->sk_info_authunix cache. - * svc_sock->sk_xprt.xpt_flags.XPT_BUSY prevents a svc_sock being - * enqueued multiply. - * - * Some flags can be set to certain values at any time - * providing that certain rules are followed: - * - * XPT_CONN, XPT_DATA, can be set or cleared at any time. - * after a set, svc_xprt_enqueue must be called. - * after a clear, the socket must be read/accepted - * if this succeeds, it must be set again. - * XPT_CLOSE can set at any time. It is never cleared. - * xpt_ref contains a bias of '1' until XPT_DEAD is set. - * so when xprt_ref hits zero, we know the transport is dead - * and no-one is using it. - * XPT_DEAD can only be set while XPT_BUSY is held which ensures - * no other thread will be using the socket or will try to - * set XPT_DEAD. - * - */ - #define RPCDBG_FACILITY RPCDBG_SVCXPRT static struct svc_sock *svc_setup_socket(struct svc_serv *, struct socket *, int *errp, int flags); -static void svc_delete_xprt(struct svc_xprt *xprt); static void svc_udp_data_ready(struct sock *, int); static int svc_udp_recvfrom(struct svc_rqst *); static int svc_udp_sendto(struct svc_rqst *); -static void svc_close_xprt(struct svc_xprt *xprt); static void svc_sock_detach(struct svc_xprt *); static void svc_sock_free(struct svc_xprt *); -static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt); -static int svc_deferred_recv(struct svc_rqst *rqstp); -static struct cache_deferred_req *svc_defer(struct cache_req *req); static struct svc_xprt *svc_create_socket(struct svc_serv *, int, struct sockaddr *, int, int); -static void svc_age_temp_xprts(unsigned long closure); - -/* apparently the "standard" is that clients close - * idle connections after 5 minutes, servers after - * 6 minutes - * http://www.connectathon.org/talks96/nfstcp.pdf - */ -static int svc_conn_age_period = 6*60; - #ifdef CONFIG_DEBUG_LOCK_ALLOC static struct lock_class_key svc_key[2]; static struct lock_class_key svc_slock_key[2]; -static inline void svc_reclassify_socket(struct socket *sock) +static void svc_reclassify_socket(struct socket *sock) { struct sock *sk = sock->sk; BUG_ON(sock_owned_by_user(sk)); @@ -131,67 +89,11 @@ static inline void svc_reclassify_socket(struct socket *sock) } } #else -static inline void svc_reclassify_socket(struct socket *sock) +static void svc_reclassify_socket(struct socket *sock) { } #endif -static char *__svc_print_addr(struct sockaddr *addr, char *buf, size_t len) -{ - switch (addr->sa_family) { - case AF_INET: - snprintf(buf, len, "%u.%u.%u.%u, port=%u", - NIPQUAD(((struct sockaddr_in *) addr)->sin_addr), - ntohs(((struct sockaddr_in *) addr)->sin_port)); - break; - - case AF_INET6: - snprintf(buf, len, "%x:%x:%x:%x:%x:%x:%x:%x, port=%u", - NIP6(((struct sockaddr_in6 *) addr)->sin6_addr), - ntohs(((struct sockaddr_in6 *) addr)->sin6_port)); - break; - - default: - snprintf(buf, len, "unknown address type: %d", addr->sa_family); - break; - } - return buf; -} - -/** - * svc_print_addr - Format rq_addr field for printing - * @rqstp: svc_rqst struct containing address to print - * @buf: target buffer for formatted address - * @len: length of target buffer - * - */ -char *svc_print_addr(struct svc_rqst *rqstp, char *buf, size_t len) -{ - return __svc_print_addr(svc_addr(rqstp), buf, len); -} -EXPORT_SYMBOL_GPL(svc_print_addr); - -/* - * Queue up an idle server thread. Must have pool->sp_lock held. - * Note: this is really a stack rather than a queue, so that we only - * use as many different threads as we need, and the rest don't pollute - * the cache. - */ -static inline void -svc_thread_enqueue(struct svc_pool *pool, struct svc_rqst *rqstp) -{ - list_add(&rqstp->rq_list, &pool->sp_threads); -} - -/* - * Dequeue an nfsd thread. Must have pool->sp_lock held. - */ -static inline void -svc_thread_dequeue(struct svc_pool *pool, struct svc_rqst *rqstp) -{ - list_del(&rqstp->rq_list); -} - /* * Release an skbuff after use */ @@ -214,220 +116,6 @@ static void svc_release_skb(struct svc_rqst *rqstp) } } -/* - * Queue up a socket with data pending. If there are idle nfsd - * processes, wake 'em up. - * - */ -void svc_xprt_enqueue(struct svc_xprt *xprt) -{ - struct svc_serv *serv = xprt->xpt_server; - struct svc_pool *pool; - struct svc_rqst *rqstp; - int cpu; - - if (!(xprt->xpt_flags & - ((1<<XPT_CONN)|(1<<XPT_DATA)|(1<<XPT_CLOSE)|(1<<XPT_DEFERRED)))) - return; - if (test_bit(XPT_DEAD, &xprt->xpt_flags)) - return; - - cpu = get_cpu(); - pool = svc_pool_for_cpu(xprt->xpt_server, cpu); - put_cpu(); - - spin_lock_bh(&pool->sp_lock); - - if (!list_empty(&pool->sp_threads) && - !list_empty(&pool->sp_sockets)) - printk(KERN_ERR - "svc_xprt_enqueue: " - "threads and transports both waiting??\n"); - - if (test_bit(XPT_DEAD, &xprt->xpt_flags)) { - /* Don't enqueue dead sockets */ - dprintk("svc: transport %p is dead, not enqueued\n", xprt); - goto out_unlock; - } - - /* Mark socket as busy. It will remain in this state until the - * server has processed all pending data and put the socket back - * on the idle list. We update XPT_BUSY atomically because - * it also guards against trying to enqueue the svc_sock twice. - */ - if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags)) { - /* Don't enqueue socket while already enqueued */ - dprintk("svc: transport %p busy, not enqueued\n", xprt); - goto out_unlock; - } - BUG_ON(xprt->xpt_pool != NULL); - xprt->xpt_pool = pool; - - /* Handle pending connection */ - if (test_bit(XPT_CONN, &xprt->xpt_flags)) - goto process; - - /* Handle close in-progress */ - if (test_bit(XPT_CLOSE, &xprt->xpt_flags)) - goto process; - - /* Check if we have space to reply to a request */ - if (!xprt->xpt_ops->xpo_has_wspace(xprt)) { - /* Don't enqueue while not enough space for reply */ - dprintk("svc: no write space, transport %p not enqueued\n", - xprt); - xprt->xpt_pool = NULL; - clear_bit(XPT_BUSY, &xprt->xpt_flags); - goto out_unlock; - } - - process: - if (!list_empty(&pool->sp_threads)) { - rqstp = list_entry(pool->sp_threads.next, - struct svc_rqst, - rq_list); - dprintk("svc: transport %p served by daemon %p\n", - xprt, rqstp); - svc_thread_dequeue(pool, rqstp); - if (rqstp->rq_xprt) - printk(KERN_ERR - "svc_xprt_enqueue: server %p, rq_xprt=%p!\n", - rqstp, rqstp->rq_xprt); - rqstp->rq_xprt = xprt; - svc_xprt_get(xprt); - rqstp->rq_reserved = serv->sv_max_mesg; - atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved); - BUG_ON(xprt->xpt_pool != pool); - wake_up(&rqstp->rq_wait); - } else { - dprintk("svc: transport %p put into queue\n", xprt); - list_add_tail(&xprt->xpt_ready, &pool->sp_sockets); - BUG_ON(xprt->xpt_pool != pool); - } - -out_unlock: - spin_unlock_bh(&pool->sp_lock); -} -EXPORT_SYMBOL_GPL(svc_xprt_enqueue); - -/* - * Dequeue the first socket. Must be called with the pool->sp_lock held. - */ -static struct svc_xprt *svc_xprt_dequeue(struct svc_pool *pool) -{ - struct svc_xprt *xprt; - - if (list_empty(&pool->sp_sockets)) - return NULL; - - xprt = list_entry(pool->sp_sockets.next, - struct svc_xprt, xpt_ready); - list_del_init(&xprt->xpt_ready); - - dprintk("svc: transport %p dequeued, inuse=%d\n", - xprt, atomic_read(&xprt->xpt_ref.refcount)); - - return xprt; -} - -/* - * svc_xprt_received conditionally queues the transport for processing - * by another thread. The caller must hold the XPT_BUSY bit and must - * not thereafter touch transport data. - * - * Note: XPT_DATA only gets cleared when a read-attempt finds no (or - * insufficient) data. - */ -void svc_xprt_received(struct svc_xprt *xprt) -{ - BUG_ON(!test_bit(XPT_BUSY, &xprt->xpt_flags)); - xprt->xpt_pool = NULL; - clear_bit(XPT_BUSY, &xprt->xpt_flags); - svc_xprt_enqueue(xprt); -} -EXPORT_SYMBOL_GPL(svc_xprt_received); - -/** - * svc_reserve - change the space reserved for the reply to a request. - * @rqstp: The request in question - * @space: new max space to reserve - * - * Each request reserves some space on the output queue of the socket - * to make sure the reply fits. This function reduces that reserved - * space to be the amount of space used already, plus @space. - * - */ -void svc_reserve(struct svc_rqst *rqstp, int space) -{ - space += rqstp->rq_res.head[0].iov_len; - - if (space < rqstp->rq_reserved) { - struct svc_xprt *xprt = rqstp->rq_xprt; - atomic_sub((rqstp->rq_reserved - space), &xprt->xpt_reserved); - rqstp->rq_reserved = space; - - svc_xprt_enqueue(xprt); - } -} - -static void svc_xprt_release(struct svc_rqst *rqstp) -{ - struct svc_xprt *xprt = rqstp->rq_xprt; - - rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp); - - svc_free_res_pages(rqstp); - rqstp->rq_res.page_len = 0; - rqstp->rq_res.page_base = 0; - - /* Reset response buffer and release - * the reservation. - * But first, check that enough space was reserved - * for the reply, otherwise we have a bug! - */ - if ((rqstp->rq_res.len) > rqstp->rq_reserved) - printk(KERN_ERR "RPC request reserved %d but used %d\n", - rqstp->rq_reserved, - rqstp->rq_res.len); - - rqstp->rq_res.head[0].iov_len = 0; - svc_reserve(rqstp, 0); - rqstp->rq_xprt = NULL; - - svc_xprt_put(xprt); -} - -/* - * External function to wake up a server waiting for data - * This really only makes sense for services like lockd - * which have exactly one thread anyway. - */ -void -svc_wake_up(struct svc_serv *serv) -{ - struct svc_rqst *rqstp; - unsigned int i; - struct svc_pool *pool; - - for (i = 0; i < serv->sv_nrpools; i++) { - pool = &serv->sv_pools[i]; - - spin_lock_bh(&pool->sp_lock); - if (!list_empty(&pool->sp_threads)) { - rqstp = list_entry(pool->sp_threads.next, - struct svc_rqst, - rq_list); - dprintk("svc: daemon %p woken up.\n", rqstp); - /* - svc_thread_dequeue(pool, rqstp); - rqstp->rq_xprt = NULL; - */ - wake_up(&rqstp->rq_wait); - } - spin_unlock_bh(&pool->sp_lock); - } -} - union svc_pktinfo_u { struct in_pktinfo pkti; struct in6_pktinfo pkti6; @@ -469,8 +157,7 @@ static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh) /* * Generic sendto routine */ -static int -svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr) +static int svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr) { struct svc_sock *svsk = container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt); @@ -605,8 +292,7 @@ EXPORT_SYMBOL(svc_sock_names); /* * Check input queue length */ -static int -svc_recv_available(struct svc_sock *svsk) +static int svc_recv_available(struct svc_sock *svsk) { struct socket *sock = svsk->sk_sock; int avail, err; @@ -619,8 +305,8 @@ svc_recv_available(struct svc_sock *svsk) /* * Generic recvfrom routine. */ -static int -svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr, int buflen) +static int svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr, + int buflen) { struct svc_sock *svsk = container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt); @@ -640,8 +326,8 @@ svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr, int buflen) /* * Set socket snd and rcv buffer lengths */ -static inline void -svc_sock_setbufsize(struct socket *sock, unsigned int snd, unsigned int rcv) +static void svc_sock_setbufsize(struct socket *sock, unsigned int snd, + unsigned int rcv) { #if 0 mm_segment_t oldfs; @@ -666,8 +352,7 @@ svc_sock_setbufsize(struct socket *sock, unsigned int snd, unsigned int rcv) /* * INET callback when data has been received on the socket. */ -static void -svc_udp_data_ready(struct sock *sk, int count) +static void svc_udp_data_ready(struct sock *sk, int count) { struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; @@ -685,8 +370,7 @@ svc_udp_data_ready(struct sock *sk, int count) /* * INET callback when space is newly available on the socket. */ -static void -svc_write_space(struct sock *sk) +static void svc_write_space(struct sock *sk) { struct svc_sock *svsk = (struct svc_sock *)(sk->sk_user_data); @@ -732,8 +416,7 @@ static void svc_udp_get_dest_address(struct svc_rqst *rqstp, /* * Receive a datagram from a UDP socket. */ -static int -svc_udp_recvfrom(struct svc_rqst *rqstp) +static int svc_udp_recvfrom(struct svc_rqst *rqstp) { struct svc_sock *svsk = container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt); @@ -827,7 +510,8 @@ svc_udp_recvfrom(struct svc_rqst *rqstp) skb_free_datagram(svsk->sk_sk, skb); } else { /* we can use it in-place */ - rqstp->rq_arg.head[0].iov_base = skb->data + sizeof(struct udphdr); + rqstp->rq_arg.head[0].iov_base = skb->data + + sizeof(struct udphdr); rqstp->rq_arg.head[0].iov_len = len; if (skb_checksum_complete(skb)) { skb_free_datagram(svsk->sk_sk, skb); @@ -938,7 +622,8 @@ static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv) 3 * svsk->sk_xprt.xpt_server->sv_max_mesg, 3 * svsk->sk_xprt.xpt_server->sv_max_mesg); - set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* might have come in before data_ready set up */ + /* data might have come in before data_ready set up */ + set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags); oldfs = get_fs(); @@ -953,8 +638,7 @@ static void svc_udp_init(struct svc_sock *svsk, struct svc_serv *serv) * A data_ready event on a listening socket means there's a connection * pending. Do not use state_change as a substitute for it. */ -static void -svc_tcp_listen_data_ready(struct sock *sk, int count_unused) +static void svc_tcp_listen_data_ready(struct sock *sk, int count_unused) { struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; @@ -986,8 +670,7 @@ svc_tcp_listen_data_ready(struct sock *sk, int count_unused) /* * A state change on a connected socket means it's dying or dead. */ -static void -svc_tcp_state_change(struct sock *sk) +static void svc_tcp_state_change(struct sock *sk) { struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; @@ -1004,8 +687,7 @@ svc_tcp_state_change(struct sock *sk) wake_up_interruptible_all(sk->sk_sleep); } -static void -svc_tcp_data_ready(struct sock *sk, int count) +static void svc_tcp_data_ready(struct sock *sk, int count) { struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; @@ -1019,20 +701,6 @@ svc_tcp_data_ready(struct sock *sk, int count) wake_up_interruptible(sk->sk_sleep); } -static inline int svc_port_is_privileged(struct sockaddr *sin) -{ - switch (sin->sa_family) { - case AF_INET: - return ntohs(((struct sockaddr_in *)sin)->sin_port) - < PROT_SOCK; - case AF_INET6: - return ntohs(((struct sockaddr_in6 *)sin)->sin6_port) - < PROT_SOCK; - default: - return 0; - } -} - /* * Accept a TCP connection */ @@ -1115,8 +783,7 @@ failed: /* * Receive data from a TCP socket. */ -static int -svc_tcp_recvfrom(struct svc_rqst *rqstp) +static int svc_tcp_recvfrom(struct svc_rqst *rqstp) { struct svc_sock *svsk = container_of(rqstp->rq_xprt, struct svc_sock, sk_xprt); @@ -1269,8 +936,7 @@ svc_tcp_recvfrom(struct svc_rqst *rqstp) /* * Send out data on TCP socket. */ -static int -svc_tcp_sendto(struct svc_rqst *rqstp) +static int svc_tcp_sendto(struct svc_rqst *rqstp) { struct xdr_buf *xbufp = &rqstp->rq_res; int sent; @@ -1288,7 +954,9 @@ svc_tcp_sendto(struct svc_rqst *rqstp) sent = svc_sendto(rqstp, &rqstp->rq_res); if (sent != xbufp->len) { - printk(KERN_NOTICE "rpc-srv/tcp: %s: %s %d when sending %d bytes - shutting down socket\n", + printk(KERN_NOTICE + "rpc-srv/tcp: %s: %s %d when sending %d bytes " + "- shutting down socket\n", rqstp->rq_xprt->xpt_server->sv_name, (sent<0)?"got error":"sent only", sent, xbufp->len); @@ -1410,8 +1078,7 @@ static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv) } } -void -svc_sock_update_bufs(struct svc_serv *serv) +void svc_sock_update_bufs(struct svc_serv *serv) { /* * The number of server threads has changed. Update @@ -1434,302 +1101,6 @@ 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_xprt *xprt = 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 " - "connections, consider increasing the " - "number of nfsd threads\n", - serv->sv_name); - } - /* - * Always select the oldest connection. It's not fair, - * but so is life - */ - xprt = list_entry(serv->sv_tempsocks.prev, - struct svc_xprt, - xpt_list); - set_bit(XPT_CLOSE, &xprt->xpt_flags); - svc_xprt_get(xprt); - } - spin_unlock_bh(&serv->sv_lock); - - if (xprt) { - svc_xprt_enqueue(xprt); - svc_xprt_put(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. - */ -int -svc_recv(struct svc_rqst *rqstp, long timeout) -{ - struct svc_xprt *xprt = NULL; - struct svc_serv *serv = rqstp->rq_server; - struct svc_pool *pool = rqstp->rq_pool; - int len, i; - int pages; - struct xdr_buf *arg; - DECLARE_WAITQUEUE(wait, current); - - dprintk("svc: server %p waiting for data (to = %ld)\n", - rqstp, timeout); - - if (rqstp->rq_xprt) - printk(KERN_ERR - "svc_recv: service %p, transport not NULL!\n", - rqstp); - if (waitqueue_active(&rqstp->rq_wait)) - printk(KERN_ERR - "svc_recv: service %p, wait queue active!\n", - rqstp); - - - /* now allocate needed pages. If we get a failure, sleep briefly */ - pages = (serv->sv_max_mesg + PAGE_SIZE) / PAGE_SIZE; - for (i=0; i < pages ; i++) - while (rqstp->rq_pages[i] == NULL) { - struct page *p = alloc_page(GFP_KERNEL); - if (!p) - schedule_timeout_uninterruptible(msecs_to_jiffies(500)); - rqstp->rq_pages[i] = p; - } - rqstp->rq_pages[i++] = NULL; /* this might be seen in nfs_read_actor */ - BUG_ON(pages >= RPCSVC_MAXPAGES); - - /* Make arg->head point to first page and arg->pages point to rest */ - arg = &rqstp->rq_arg; - arg->head[0].iov_base = page_address(rqstp->rq_pages[0]); - arg->head[0].iov_len = PAGE_SIZE; - arg->pages = rqstp->rq_pages + 1; - arg->page_base = 0; - /* save at least one page for response */ - arg->page_len = (pages-2)*PAGE_SIZE; - arg->len = (pages-1)*PAGE_SIZE; - arg->tail[0].iov_len = 0; - - try_to_freeze(); - cond_resched(); - if (signalled()) - return -EINTR; - - spin_lock_bh(&pool->sp_lock); - xprt = svc_xprt_dequeue(pool); - if (xprt) { - rqstp->rq_xprt = xprt; - svc_xprt_get(xprt); - rqstp->rq_reserved = serv->sv_max_mesg; - atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved); - } else { - /* No data pending. Go to sleep */ - svc_thread_enqueue(pool, rqstp); - - /* - * We have to be able to interrupt this wait - * to bring down the daemons ... - */ - set_current_state(TASK_INTERRUPTIBLE); - add_wait_queue(&rqstp->rq_wait, &wait); - spin_unlock_bh(&pool->sp_lock); - - schedule_timeout(timeout); - - try_to_freeze(); - - spin_lock_bh(&pool->sp_lock); - remove_wait_queue(&rqstp->rq_wait, &wait); - - xprt = rqstp->rq_xprt; - if (!xprt) { - svc_thread_dequeue(pool, rqstp); - spin_unlock_bh(&pool->sp_lock); - dprintk("svc: server %p, no data yet\n", rqstp); - return signalled()? -EINTR : -EAGAIN; - } - } - spin_unlock_bh(&pool->sp_lock); - - len = 0; - if (test_bit(XPT_CLOSE, &xprt->xpt_flags)) { - dprintk("svc_recv: found XPT_CLOSE\n"); - svc_delete_xprt(xprt); - } else if (test_bit(XPT_LISTENER, &xprt->xpt_flags)) { - struct svc_xprt *newxpt; - newxpt = xprt->xpt_ops->xpo_accept(xprt); - if (newxpt) { - /* - * We know this module_get will succeed because the - * listener holds a reference too - */ - __module_get(newxpt->xpt_class->xcl_owner); - svc_check_conn_limits(xprt->xpt_server); - spin_lock_bh(&serv->sv_lock); - set_bit(XPT_TEMP, &newxpt->xpt_flags); - list_add(&newxpt->xpt_list, &serv->sv_tempsocks); - serv->sv_tmpcnt++; - if (serv->sv_temptimer.function == NULL) { - /* setup timer to age temp sockets */ - setup_timer(&serv->sv_temptimer, - svc_age_temp_xprts, - (unsigned long)serv); - mod_timer(&serv->sv_temptimer, - jiffies + svc_conn_age_period * HZ); - } - spin_unlock_bh(&serv->sv_lock); - svc_xprt_received(newxpt); - } - svc_xprt_received(xprt); - } else { - dprintk("svc: server %p, pool %u, transport %p, inuse=%d\n", - rqstp, pool->sp_id, xprt, - atomic_read(&xprt->xpt_ref.refcount)); - rqstp->rq_deferred = svc_deferred_dequeue(xprt); - if (rqstp->rq_deferred) { - svc_xprt_received(xprt); - len = svc_deferred_recv(rqstp); - } else - len = xprt->xpt_ops->xpo_recvfrom(rqstp); - dprintk("svc: got len=%d\n", len); - } - - /* No data, incomplete (TCP) read, or accept() */ - if (len == 0 || len == -EAGAIN) { - rqstp->rq_res.len = 0; - svc_xprt_release(rqstp); - return -EAGAIN; - } - clear_bit(XPT_OLD, &xprt->xpt_flags); - - rqstp->rq_secure = svc_port_is_privileged(svc_addr(rqstp)); - rqstp->rq_chandle.defer = svc_defer; - - if (serv->sv_stats) - serv->sv_stats->netcnt++; - return len; -} - -/* - * Drop request - */ -void -svc_drop(struct svc_rqst *rqstp) -{ - dprintk("svc: xprt %p dropped request\n", rqstp->rq_xprt); - svc_xprt_release(rqstp); -} - -/* - * Return reply to client. - */ -int -svc_send(struct svc_rqst *rqstp) -{ - struct svc_xprt *xprt; - int len; - struct xdr_buf *xb; - - xprt = rqstp->rq_xprt; - if (!xprt) - return -EFAULT; - - /* release the receive skb before sending the reply */ - rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp); - - /* calculate over-all length */ - xb = & rqstp->rq_res; - xb->len = xb->head[0].iov_len + - xb->page_len + - xb->tail[0].iov_len; - - /* Grab mutex to serialize outgoing data. */ - mutex_lock(&xprt->xpt_mutex); - if (test_bit(XPT_DEAD, &xprt->xpt_flags)) - len = -ENOTCONN; - else - len = xprt->xpt_ops->xpo_sendto(rqstp); - mutex_unlock(&xprt->xpt_mutex); - svc_xprt_release(rqstp); - - if (len == -ECONNREFUSED || len == -ENOTCONN || len == -EAGAIN) - return 0; - return len; -} - -/* - * Timer function to close old temporary sockets, using - * a mark-and-sweep algorithm. - */ -static void svc_age_temp_xprts(unsigned long closure) -{ - struct svc_serv *serv = (struct svc_serv *)closure; - struct svc_xprt *xprt; - struct list_head *le, *next; - LIST_HEAD(to_be_aged); - - dprintk("svc_age_temp_xprts\n"); - - if (!spin_trylock_bh(&serv->sv_lock)) { - /* busy, try again 1 sec later */ - dprintk("svc_age_temp_xprts: busy\n"); - mod_timer(&serv->sv_temptimer, jiffies + HZ); - return; - } - - list_for_each_safe(le, next, &serv->sv_tempsocks) { - xprt = list_entry(le, struct svc_xprt, xpt_list); - - /* First time through, just mark it OLD. Second time - * through, close it. */ - if (!test_and_set_bit(XPT_OLD, &xprt->xpt_flags)) - continue; - if (atomic_read(&xprt->xpt_ref.refcount) > 1 - || test_bit(XPT_BUSY, &xprt->xpt_flags)) - continue; - svc_xprt_get(xprt); - list_move(le, &to_be_aged); - set_bit(XPT_CLOSE, &xprt->xpt_flags); - set_bit(XPT_DETACHED, &xprt->xpt_flags); - } - spin_unlock_bh(&serv->sv_lock); - - while (!list_empty(&to_be_aged)) { - le = to_be_aged.next; - /* fiddling the xpt_list node is safe 'cos we're XPT_DETACHED */ - list_del_init(le); - xprt = list_entry(le, struct svc_xprt, xpt_list); - - dprintk("queuing xprt %p for closing\n", xprt); - - /* a thread will dequeue and close it soon */ - svc_xprt_enqueue(xprt); - svc_xprt_put(xprt); - } - - mod_timer(&serv->sv_temptimer, jiffies + svc_conn_age_period * HZ); -} - -/* * Initialize socket for RPC use and create svc_sock struct * XXX: May want to setsockopt SO_SNDBUF and SO_RCVBUF. */ @@ -1913,160 +1284,3 @@ static void svc_sock_free(struct svc_xprt *xprt) sock_release(svsk->sk_sock); kfree(svsk); } - -/* - * Remove a dead transport - */ -static void svc_delete_xprt(struct svc_xprt *xprt) -{ - struct svc_serv *serv = xprt->xpt_server; - - dprintk("svc: svc_delete_xprt(%p)\n", xprt); - xprt->xpt_ops->xpo_detach(xprt); - - spin_lock_bh(&serv->sv_lock); - if (!test_and_set_bit(XPT_DETACHED, &xprt->xpt_flags)) - list_del_init(&xprt->xpt_list); - /* - * We used to delete the transport from whichever list - * it's sk_xprt.xpt_ready node was on, but we don't actually - * need to. This is because the only time we're called - * while still attached to a queue, the queue itself - * is about to be destroyed (in svc_destroy). - */ - if (!test_and_set_bit(XPT_DEAD, &xprt->xpt_flags)) { - BUG_ON(atomic_read(&xprt->xpt_ref.refcount) < 2); - if (test_bit(XPT_TEMP, &xprt->xpt_flags)) - serv->sv_tmpcnt--; - svc_xprt_put(xprt); - } - spin_unlock_bh(&serv->sv_lock); -} - -static void svc_close_xprt(struct svc_xprt *xprt) -{ - set_bit(XPT_CLOSE, &xprt->xpt_flags); - if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags)) - /* someone else will have to effect the close */ - return; - - svc_xprt_get(xprt); - svc_delete_xprt(xprt); - clear_bit(XPT_BUSY, &xprt->xpt_flags); - svc_xprt_put(xprt); -} - -void svc_close_all(struct list_head *xprt_list) -{ - struct svc_xprt *xprt; - struct svc_xprt *tmp; - - list_for_each_entry_safe(xprt, tmp, xprt_list, xpt_list) { - set_bit(XPT_CLOSE, &xprt->xpt_flags); - if (test_bit(XPT_BUSY, &xprt->xpt_flags)) { - /* Waiting to be processed, but no threads left, - * So just remove it from the waiting list - */ - list_del_init(&xprt->xpt_ready); - clear_bit(XPT_BUSY, &xprt->xpt_flags); - } - svc_close_xprt(xprt); - } -} - -/* - * Handle defer and revisit of requests - */ - -static void svc_revisit(struct cache_deferred_req *dreq, int too_many) -{ - struct svc_deferred_req *dr = container_of(dreq, struct svc_deferred_req, handle); - struct svc_xprt *xprt = dr->xprt; - - if (too_many) { - svc_xprt_put(xprt); - kfree(dr); - return; - } - dprintk("revisit queued\n"); - dr->xprt = NULL; - spin_lock(&xprt->xpt_lock); - list_add(&dr->handle.recent, &xprt->xpt_deferred); - spin_unlock(&xprt->xpt_lock); - set_bit(XPT_DEFERRED, &xprt->xpt_flags); - svc_xprt_enqueue(xprt); - svc_xprt_put(xprt); -} - -static struct cache_deferred_req * -svc_defer(struct cache_req *req) -{ - struct svc_rqst *rqstp = container_of(req, struct svc_rqst, rq_chandle); - int size = sizeof(struct svc_deferred_req) + (rqstp->rq_arg.len); - struct svc_deferred_req *dr; - - if (rqstp->rq_arg.page_len) - return NULL; /* if more than a page, give up FIXME */ - if (rqstp->rq_deferred) { - dr = rqstp->rq_deferred; - rqstp->rq_deferred = NULL; - } else { - int skip = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len; - /* FIXME maybe discard if size too large */ - dr = kmalloc(size, GFP_KERNEL); - if (dr == NULL) - return NULL; - - dr->handle.owner = rqstp->rq_server; - dr->prot = rqstp->rq_prot; - memcpy(&dr->addr, &rqstp->rq_addr, rqstp->rq_addrlen); - dr->addrlen = rqstp->rq_addrlen; - dr->daddr = rqstp->rq_daddr; - dr->argslen = rqstp->rq_arg.len >> 2; - memcpy(dr->args, rqstp->rq_arg.head[0].iov_base-skip, dr->argslen<<2); - } - svc_xprt_get(rqstp->rq_xprt); - dr->xprt = rqstp->rq_xprt; - - dr->handle.revisit = svc_revisit; - return &dr->handle; -} - -/* - * recv data from a deferred request into an active one - */ -static int svc_deferred_recv(struct svc_rqst *rqstp) -{ - struct svc_deferred_req *dr = rqstp->rq_deferred; - - rqstp->rq_arg.head[0].iov_base = dr->args; - rqstp->rq_arg.head[0].iov_len = dr->argslen<<2; - rqstp->rq_arg.page_len = 0; - rqstp->rq_arg.len = dr->argslen<<2; - rqstp->rq_prot = dr->prot; - memcpy(&rqstp->rq_addr, &dr->addr, dr->addrlen); - rqstp->rq_addrlen = dr->addrlen; - rqstp->rq_daddr = dr->daddr; - rqstp->rq_respages = rqstp->rq_pages; - return dr->argslen<<2; -} - - -static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt) -{ - struct svc_deferred_req *dr = NULL; - - if (!test_bit(XPT_DEFERRED, &xprt->xpt_flags)) - return NULL; - spin_lock(&xprt->xpt_lock); - clear_bit(XPT_DEFERRED, &xprt->xpt_flags); - if (!list_empty(&xprt->xpt_deferred)) { - dr = list_entry(xprt->xpt_deferred.next, - struct svc_deferred_req, - handle.recent); - list_del_init(&dr->handle.recent); - set_bit(XPT_DEFERRED, &xprt->xpt_flags); - } - spin_unlock(&xprt->xpt_lock); - return dr; -} |