/* * linux/net/sunrpc/svcsock.c * * These are the RPC server socket internals. * * The server scheduling algorithm does not always distribute the load * evenly when servicing a single client. May need to modify the * svc_sock_enqueue procedure... * * TCP support is largely untested and may be a little slow. The problem * is that we currently do two separate recvfrom's, one for the 4-byte * record length, and the second for the actual record. This could possibly * be improved by always reading a minimum size of around 100 bytes and * tucking any superfluous bytes away in a temporary store. Still, that * leaves write requests out in the rain. An alternative may be to peek at * the first skb in the queue, and if it matches the next TCP sequence * number, to extract the record marker. Yuck. * * Copyright (C) 1995, 1996 Olaf Kirch */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* 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_flags.SK_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: * * SK_CONN, SK_DATA, can be set or cleared at any time. * after a set, svc_sock_enqueue must be called. * 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 * 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 * set SK_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_socket(struct svc_sock *svsk); 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_socket(struct svc_sock *svsk); 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_sock *svsk); static int svc_deferred_recv(struct svc_rqst *rqstp); static struct cache_deferred_req *svc_defer(struct cache_req *req); /* 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) { struct sock *sk = sock->sk; BUG_ON(sock_owned_by_user(sk)); switch (sk->sk_family) { case AF_INET: sock_lock_init_class_and_name(sk, "slock-AF_INET-NFSD", &svc_slock_key[0], "sk_lock-AF_INET-NFSD", &svc_key[0]); break; case AF_INET6: sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFSD", &svc_slock_key[1], "sk_lock-AF_INET6-NFSD", &svc_key[1]); break; default: BUG(); } } #else static inline 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 */ static void svc_release_skb(struct svc_rqst *rqstp) { struct sk_buff *skb = rqstp->rq_xprt_ctxt; struct svc_deferred_req *dr = rqstp->rq_deferred; if (skb) { rqstp->rq_xprt_ctxt = NULL; dprintk("svc: service %p, releasing skb %p\n", rqstp, skb); skb_free_datagram(rqstp->rq_sock->sk_sk, skb); } if (dr) { rqstp->rq_deferred = NULL; kfree(dr); } } /* * Queue up a socket with data pending. If there are idle nfsd * processes, wake 'em up. * */ static void svc_sock_enqueue(struct svc_sock *svsk) { struct svc_serv *serv = svsk->sk_server; struct svc_pool *pool; struct svc_rqst *rqstp; int cpu; if (!(svsk->sk_flags & ( (1<sk_flags)) return; cpu = get_cpu(); pool = svc_pool_for_cpu(svsk->sk_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_sock_enqueue: threads and sockets both waiting??\n"); if (test_bit(SK_DEAD, &svsk->sk_flags)) { /* Don't enqueue dead sockets */ dprintk("svc: socket %p is dead, not enqueued\n", svsk->sk_sk); 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 SK_BUSY atomically because * it also guards against trying to enqueue the svc_sock twice. */ if (test_and_set_bit(SK_BUSY, &svsk->sk_flags)) { /* Don't enqueue socket while already enqueued */ dprintk("svc: socket %p busy, not enqueued\n", svsk->sk_sk); goto out_unlock; } BUG_ON(svsk->sk_pool != NULL); svsk->sk_pool = pool; /* Handle pending connection */ if (test_bit(SK_CONN, &svsk->sk_flags)) goto process; /* Handle close in-progress */ if (test_bit(SK_CLOSE, &svsk->sk_flags)) goto process; /* Check if we have space to reply to a request */ if (!svsk->sk_xprt.xpt_ops->xpo_has_wspace(&svsk->sk_xprt)) { /* Don't enqueue while not enough space for reply */ dprintk("svc: no write space, socket %p not enqueued\n", svsk); svsk->sk_pool = NULL; clear_bit(SK_BUSY, &svsk->sk_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: socket %p served by daemon %p\n", svsk->sk_sk, rqstp); svc_thread_dequeue(pool, rqstp); if (rqstp->rq_sock) printk(KERN_ERR "svc_sock_enqueue: server %p, rq_sock=%p!\n", rqstp, rqstp->rq_sock); rqstp->rq_sock = svsk; atomic_inc(&svsk->sk_inuse); rqstp->rq_reserved = serv->sv_max_mesg; atomic_add(rqstp->rq_reserved, &svsk->sk_reserved); BUG_ON(svsk->sk_pool != pool); wake_up(&rqstp->rq_wait); } else { dprintk("svc: socket %p put into queue\n", svsk->sk_sk); list_add_tail(&svsk->sk_ready, &pool->sp_sockets); BUG_ON(svsk->sk_pool != pool); } out_unlock: spin_unlock_bh(&pool->sp_lock); } /* * Dequeue the first socket. Must be called with the pool->sp_lock held. */ static inline struct svc_sock * svc_sock_dequeue(struct svc_pool *pool) { struct svc_sock *svsk; if (list_empty(&pool->sp_sockets)) return NULL; svsk = list_entry(pool->sp_sockets.next, struct svc_sock, sk_ready); list_del_init(&svsk->sk_ready); dprintk("svc: socket %p dequeued, inuse=%d\n", svsk->sk_sk, atomic_read(&svsk->sk_inuse)); return svsk; } /* * Having read something from a socket, check whether it * needs to be re-enqueued. * Note: SK_DATA only gets cleared when a read-attempt finds * no (or insufficient) data. */ static inline void svc_sock_received(struct svc_sock *svsk) { svsk->sk_pool = NULL; clear_bit(SK_BUSY, &svsk->sk_flags); svc_sock_enqueue(svsk); } /** * 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_sock *svsk = rqstp->rq_sock; atomic_sub((rqstp->rq_reserved - space), &svsk->sk_reserved); rqstp->rq_reserved = space; svc_sock_enqueue(svsk); } } /* * 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)); svsk->sk_xprt.xpt_ops->xpo_free(&svsk->sk_xprt); } } static void svc_sock_release(struct svc_rqst *rqstp) { struct svc_sock *svsk = rqstp->rq_sock; 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_sock = NULL; svc_sock_put(svsk); } /* * 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_sock = NULL; */ wake_up(&rqstp->rq_wait); } spin_unlock_bh(&pool->sp_lock); } } union svc_pktinfo_u { struct in_pktinfo pkti; struct in6_pktinfo pkti6; }; #define SVC_PKTINFO_SPACE \ CMSG_SPACE(sizeof(union svc_pktinfo_u)) static void svc_set_cmsg_data(struct svc_rqst *rqstp, struct cmsghdr *cmh) { switch (rqstp->rq_sock->sk_sk->sk_family) { case AF_INET: { struct in_pktinfo *pki = CMSG_DATA(cmh); cmh->cmsg_level = SOL_IP; cmh->cmsg_type = IP_PKTINFO; pki->ipi_ifindex = 0; pki->ipi_spec_dst.s_addr = rqstp->rq_daddr.addr.s_addr; cmh->cmsg_len = CMSG_LEN(sizeof(*pki)); } break; case AF_INET6: { struct in6_pktinfo *pki = CMSG_DATA(cmh); cmh->cmsg_level = SOL_IPV6; cmh->cmsg_type = IPV6_PKTINFO; pki->ipi6_ifindex = 0; ipv6_addr_copy(&pki->ipi6_addr, &rqstp->rq_daddr.addr6); cmh->cmsg_len = CMSG_LEN(sizeof(*pki)); } break; } return; } /* * Generic sendto routine */ static int svc_sendto(struct svc_rqst *rqstp, struct xdr_buf *xdr) { struct svc_sock *svsk = rqstp->rq_sock; struct socket *sock = svsk->sk_sock; int slen; union { struct cmsghdr hdr; long all[SVC_PKTINFO_SPACE / sizeof(long)]; } buffer; struct cmsghdr *cmh = &buffer.hdr; int len = 0; int result; int size; struct page **ppage = xdr->pages; size_t base = xdr->page_base; unsigned int pglen = xdr->page_len; unsigned int flags = MSG_MORE; char buf[RPC_MAX_ADDRBUFLEN]; slen = xdr->len; if (rqstp->rq_prot == IPPROTO_UDP) { struct msghdr msg = { .msg_name = &rqstp->rq_addr, .msg_namelen = rqstp->rq_addrlen, .msg_control = cmh, .msg_controllen = sizeof(buffer), .msg_flags = MSG_MORE, }; svc_set_cmsg_data(rqstp, cmh); if (sock_sendmsg(sock, &msg, 0) < 0) goto out; } /* send head */ if (slen == xdr->head[0].iov_len) flags = 0; len = kernel_sendpage(sock, rqstp->rq_respages[0], 0, xdr->head[0].iov_len, flags); if (len != xdr->head[0].iov_len) goto out; slen -= xdr->head[0].iov_len; if (slen == 0) goto out; /* send page data */ size = PAGE_SIZE - base < pglen ? PAGE_SIZE - base : pglen; while (pglen > 0) { if (slen == size) flags = 0; result = kernel_sendpage(sock, *ppage, base, size, flags); if (result > 0) len += result; if (result != size) goto out; slen -= size; pglen -= size; size = PAGE_SIZE < pglen ? PAGE_SIZE : pglen; base = 0; ppage++; } /* send tail */ if (xdr->tail[0].iov_len) { result = kernel_sendpage(sock, rqstp->rq_respages[0], ((unsigned long)xdr->tail[0].iov_base) & (PAGE_SIZE-1), xdr->tail[0].iov_len, 0); if (result > 0) len += result; } out: dprintk("svc: socket %p sendto([%p %Zu... ], %d) = %d (addr %s)\n", rqstp->rq_sock, xdr->head[0].iov_base, xdr->head[0].iov_len, xdr->len, len, svc_print_addr(rqstp, buf, sizeof(buf))); return len; } /* * Report socket names for nfsdfs */ static int one_sock_name(char *buf, struct svc_sock *svsk) { int len; switch(svsk->sk_sk->sk_family) { case AF_INET: len = sprintf(buf, "ipv4 %s %u.%u.%u.%u %d\n", svsk->sk_sk->sk_protocol==IPPROTO_UDP? "udp" : "tcp", NIPQUAD(inet_sk(svsk->sk_sk)->rcv_saddr), inet_sk(svsk->sk_sk)->num); break; default: len = sprintf(buf, "*unknown-%d*\n", svsk->sk_sk->sk_family); } return len; } int svc_sock_names(char *buf, struct svc_serv *serv, char *toclose) { struct svc_sock *svsk, *closesk = NULL; int len = 0; if (!serv) return 0; spin_lock_bh(&serv->sv_lock); list_for_each_entry(svsk, &serv->sv_permsocks, sk_list) { int onelen = one_sock_name(buf+len, svsk); if (toclose && strcmp(toclose, buf+len) == 0) closesk = svsk; else len += onelen; } spin_unlock_bh(&serv->sv_lock); if (closesk) /* Should unregister with portmap, but you cannot * unregister just one protocol... */ svc_close_socket(closesk); else if (toclose) return -ENOENT; return len; } EXPORT_SYMBOL(svc_sock_names); /* * Check input queue length */ static int svc_recv_available(struct svc_sock *svsk) { struct socket *sock = svsk->sk_sock; int avail, err; err = kernel_sock_ioctl(sock, TIOCINQ, (unsigned long) &avail); return (err >= 0)? avail : err; } /* * Generic recvfrom routine. */ static int svc_recvfrom(struct svc_rqst *rqstp, struct kvec *iov, int nr, int buflen) { struct svc_sock *svsk = rqstp->rq_sock; struct msghdr msg = { .msg_flags = MSG_DONTWAIT, }; struct sockaddr *sin; int len; len = kernel_recvmsg(svsk->sk_sock, &msg, iov, nr, buflen, msg.msg_flags); /* sock_recvmsg doesn't fill in the name/namelen, so we must.. */ memcpy(&rqstp->rq_addr, &svsk->sk_remote, svsk->sk_remotelen); rqstp->rq_addrlen = svsk->sk_remotelen; /* Destination address in request is needed for binding the * source address in RPC callbacks later. */ sin = (struct sockaddr *)&svsk->sk_local; switch (sin->sa_family) { case AF_INET: rqstp->rq_daddr.addr = ((struct sockaddr_in *)sin)->sin_addr; break; case AF_INET6: rqstp->rq_daddr.addr6 = ((struct sockaddr_in6 *)sin)->sin6_addr; break; } dprintk("svc: socket %p recvfrom(%p, %Zu) = %d\n", svsk, iov[0].iov_base, iov[0].iov_len, len); return len; } /* * Set socket snd and rcv buffer lengths */ static inline void svc_sock_setbufsize(struct socket *sock, unsigned int snd, unsigned int rcv) { #if 0 mm_segment_t oldfs; oldfs = get_fs(); set_fs(KERNEL_DS); sock_setsockopt(sock, SOL_SOCKET, SO_SNDBUF, (char*)&snd, sizeof(snd)); sock_setsockopt(sock, SOL_SOCKET, SO_RCVBUF, (char*)&rcv, sizeof(rcv)); #else /* sock_setsockopt limits use to sysctl_?mem_max, * which isn't acceptable. Until that is made conditional * on not having CAP_SYS_RESOURCE or similar, we go direct... * DaveM said I could! */ lock_sock(sock->sk); sock->sk->sk_sndbuf = snd * 2; sock->sk->sk_rcvbuf = rcv * 2; sock->sk->sk_userlocks |= SOCK_SNDBUF_LOCK|SOCK_RCVBUF_LOCK; release_sock(sock->sk); #endif } /* * INET callback when data has been received on the socket. */ static void svc_udp_data_ready(struct sock *sk, int count) { struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; if (svsk) { dprintk("svc: socket %p(inet %p), count=%d, busy=%d\n", svsk, sk, count, test_bit(SK_BUSY, &svsk->sk_flags)); set_bit(SK_DATA, &svsk->sk_flags); svc_sock_enqueue(svsk); } if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) wake_up_interruptible(sk->sk_sleep); } /* * INET callback when space is newly available on the socket. */ static void svc_write_space(struct sock *sk) { struct svc_sock *svsk = (struct svc_sock *)(sk->sk_user_data); if (svsk) { dprintk("svc: socket %p(inet %p), write_space busy=%d\n", svsk, sk, test_bit(SK_BUSY, &svsk->sk_flags)); svc_sock_enqueue(svsk); } if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) { dprintk("RPC svc_write_space: someone sleeping on %p\n", svsk); wake_up_interruptible(sk->sk_sleep); } } static inline void svc_udp_get_dest_address(struct svc_rqst *rqstp, struct cmsghdr *cmh) { switch (rqstp->rq_sock->sk_sk->sk_family) { case AF_INET: { struct in_pktinfo *pki = CMSG_DATA(cmh); rqstp->rq_daddr.addr.s_addr = pki->ipi_spec_dst.s_addr; break; } case AF_INET6: { struct in6_pktinfo *pki = CMSG_DATA(cmh); ipv6_addr_copy(&rqstp->rq_daddr.addr6, &pki->ipi6_addr); break; } } } /* * Receive a datagram from a UDP socket. */ static int svc_udp_recvfrom(struct svc_rqst *rqstp) { struct svc_sock *svsk = rqstp->rq_sock; struct svc_serv *serv = svsk->sk_server; struct sk_buff *skb; union { struct cmsghdr hdr; long all[SVC_PKTINFO_SPACE / sizeof(long)]; } buffer; struct cmsghdr *cmh = &buffer.hdr; int err, len; struct msghdr msg = { .msg_name = svc_addr(rqstp), .msg_control = cmh, .msg_controllen = sizeof(buffer), .msg_flags = MSG_DONTWAIT, }; if (test_and_clear_bit(SK_CHNGBUF, &svsk->sk_flags)) /* udp sockets need large rcvbuf as all pending * requests are still in that buffer. sndbuf must * also be large enough that there is enough space * for one reply per thread. We count all threads * rather than threads in a particular pool, which * provides an upper bound on the number of threads * which will access the socket. */ svc_sock_setbufsize(svsk->sk_sock, (serv->sv_nrthreads+3) * serv->sv_max_mesg, (serv->sv_nrthreads+3) * serv->sv_max_mesg); if ((rqstp->rq_deferred = svc_deferred_dequeue(svsk))) { svc_sock_received(svsk); return svc_deferred_recv(rqstp); } clear_bit(SK_DATA, &svsk->sk_flags); skb = NULL; err = kernel_recvmsg(svsk->sk_sock, &msg, NULL, 0, 0, MSG_PEEK | MSG_DONTWAIT); if (err >= 0) skb = skb_recv_datagram(svsk->sk_sk, 0, 1, &err); if (skb == NULL) { if (err != -EAGAIN) { /* possibly an icmp error */ dprintk("svc: recvfrom returned error %d\n", -err); set_bit(SK_DATA, &svsk->sk_flags); } svc_sock_received(svsk); return -EAGAIN; } rqstp->rq_addrlen = sizeof(rqstp->rq_addr); if (skb->tstamp.tv64 == 0) { skb->tstamp = ktime_get_real(); /* Don't enable netstamp, sunrpc doesn't need that much accuracy */ } svsk->sk_sk->sk_stamp = skb->tstamp; set_bit(SK_DATA, &svsk->sk_flags); /* there may be more data... */ /* * Maybe more packets - kick another thread ASAP. */ svc_sock_received(svsk); len = skb->len - sizeof(struct udphdr); rqstp->rq_arg.len = len; rqstp->rq_prot = IPPROTO_UDP; if (cmh->cmsg_level != IPPROTO_IP || cmh->cmsg_type != IP_PKTINFO) { if (net_ratelimit()) printk("rpcsvc: received unknown control message:" "%d/%d\n", cmh->cmsg_level, cmh->cmsg_type); skb_free_datagram(svsk->sk_sk, skb); return 0; } svc_udp_get_dest_address(rqstp, cmh); if (skb_is_nonlinear(skb)) { /* we have to copy */ local_bh_disable(); if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb)) { local_bh_enable(); /* checksum error */ skb_free_datagram(svsk->sk_sk, skb); return 0; } local_bh_enable(); 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_len = len; if (skb_checksum_complete(skb)) { skb_free_datagram(svsk->sk_sk, skb); return 0; } rqstp->rq_xprt_ctxt = skb; } rqstp->rq_arg.page_base = 0; if (len <= rqstp->rq_arg.head[0].iov_len) { rqstp->rq_arg.head[0].iov_len = len; rqstp->rq_arg.page_len = 0; rqstp->rq_respages = rqstp->rq_pages+1; } else { rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len; rqstp->rq_respages = rqstp->rq_pages + 1 + DIV_ROUND_UP(rqstp->rq_arg.page_len, PAGE_SIZE); } if (serv->sv_stats) serv->sv_stats->netudpcnt++; return len; } static int svc_udp_sendto(struct svc_rqst *rqstp) { int error; error = svc_sendto(rqstp, &rqstp->rq_res); if (error == -ECONNREFUSED) /* ICMP error on earlier request. */ error = svc_sendto(rqstp, &rqstp->rq_res); return error; } static void svc_udp_prep_reply_hdr(struct svc_rqst *rqstp) { } static int svc_udp_has_wspace(struct svc_xprt *xprt) { struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); struct svc_serv *serv = svsk->sk_server; unsigned long required; /* * Set the SOCK_NOSPACE flag before checking the available * sock space. */ set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags); required = atomic_read(&svsk->sk_reserved) + serv->sv_max_mesg; if (required*2 > sock_wspace(svsk->sk_sk)) return 0; clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags); return 1; } static struct svc_xprt *svc_udp_accept(struct svc_xprt *xprt) { BUG(); return NULL; } static struct svc_xprt_ops svc_udp_ops = { .xpo_recvfrom = svc_udp_recvfrom, .xpo_sendto = svc_udp_sendto, .xpo_release_rqst = svc_release_skb, .xpo_detach = svc_sock_detach, .xpo_free = svc_sock_free, .xpo_prep_reply_hdr = svc_udp_prep_reply_hdr, .xpo_has_wspace = svc_udp_has_wspace, .xpo_accept = svc_udp_accept, }; static struct svc_xprt_class svc_udp_class = { .xcl_name = "udp", .xcl_ops = &svc_udp_ops, .xcl_max_payload = RPCSVC_MAXPAYLOAD_UDP, }; static void svc_udp_init(struct svc_sock *svsk) { int one = 1; mm_segment_t oldfs; svc_xprt_init(&svc_udp_class, &svsk->sk_xprt); svsk->sk_sk->sk_data_ready = svc_udp_data_ready; svsk->sk_sk->sk_write_space = svc_write_space; /* initialise setting must have enough space to * receive and respond to one request. * svc_udp_recvfrom will re-adjust if necessary */ svc_sock_setbufsize(svsk->sk_sock, 3 * svsk->sk_server->sv_max_mesg, 3 * svsk->sk_server->sv_max_mesg); set_bit(SK_DATA, &svsk->sk_flags); /* might have come in before data_ready set up */ set_bit(SK_CHNGBUF, &svsk->sk_flags); oldfs = get_fs(); set_fs(KERNEL_DS); /* make sure we get destination address info */ svsk->sk_sock->ops->setsockopt(svsk->sk_sock, IPPROTO_IP, IP_PKTINFO, (char __user *)&one, sizeof(one)); set_fs(oldfs); } /* * 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) { struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; dprintk("svc: socket %p TCP (listen) state change %d\n", sk, sk->sk_state); /* * This callback may called twice when a new connection * is established as a child socket inherits everything * from a parent LISTEN socket. * 1) data_ready method of the parent socket will be called * when one of child sockets become ESTABLISHED. * 2) data_ready method of the child socket may be called * when it receives data before the socket is accepted. * In case of 2, we should ignore it silently. */ if (sk->sk_state == TCP_LISTEN) { if (svsk) { set_bit(SK_CONN, &svsk->sk_flags); svc_sock_enqueue(svsk); } else printk("svc: socket %p: no user data\n", sk); } if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) wake_up_interruptible_all(sk->sk_sleep); } /* * A state change on a connected socket means it's dying or dead. */ static void svc_tcp_state_change(struct sock *sk) { struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; dprintk("svc: socket %p TCP (connected) state change %d (svsk %p)\n", sk, sk->sk_state, sk->sk_user_data); if (!svsk) printk("svc: socket %p: no user data\n", sk); else { set_bit(SK_CLOSE, &svsk->sk_flags); svc_sock_enqueue(svsk); } if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) wake_up_interruptible_all(sk->sk_sleep); } static void svc_tcp_data_ready(struct sock *sk, int count) { struct svc_sock *svsk = (struct svc_sock *)sk->sk_user_data; dprintk("svc: socket %p TCP data ready (svsk %p)\n", sk, sk->sk_user_data); if (svsk) { set_bit(SK_DATA, &svsk->sk_flags); svc_sock_enqueue(svsk); } if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) 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 */ static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt) { struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); struct sockaddr_storage addr; struct sockaddr *sin = (struct sockaddr *) &addr; struct svc_serv *serv = svsk->sk_server; struct socket *sock = svsk->sk_sock; struct socket *newsock; struct svc_sock *newsvsk; int err, slen; char buf[RPC_MAX_ADDRBUFLEN]; dprintk("svc: tcp_accept %p sock %p\n", svsk, sock); if (!sock) return NULL; clear_bit(SK_CONN, &svsk->sk_flags); err = kernel_accept(sock, &newsock, O_NONBLOCK); if (err < 0) { if (err == -ENOMEM) printk(KERN_WARNING "%s: no more sockets!\n", serv->sv_name); else if (err != -EAGAIN && net_ratelimit()) printk(KERN_WARNING "%s: accept failed (err %d)!\n", serv->sv_name, -err); return NULL; } set_bit(SK_CONN, &svsk->sk_flags); err = kernel_getpeername(newsock, sin, &slen); if (err < 0) { if (net_ratelimit()) printk(KERN_WARNING "%s: peername failed (err %d)!\n", serv->sv_name, -err); goto failed; /* aborted connection or whatever */ } /* Ideally, we would want to reject connections from unauthorized * hosts here, but when we get encryption, the IP of the host won't * tell us anything. For now just warn about unpriv connections. */ if (!svc_port_is_privileged(sin)) { dprintk(KERN_WARNING "%s: connect from unprivileged port: %s\n", serv->sv_name, __svc_print_addr(sin, buf, sizeof(buf))); } dprintk("%s: connect from %s\n", serv->sv_name, __svc_print_addr(sin, buf, sizeof(buf))); /* make sure that a write doesn't block forever when * low on memory */ newsock->sk->sk_sndtimeo = HZ*30; if (!(newsvsk = svc_setup_socket(serv, newsock, &err, (SVC_SOCK_ANONYMOUS | SVC_SOCK_TEMPORARY)))) goto failed; memcpy(&newsvsk->sk_remote, sin, slen); newsvsk->sk_remotelen = slen; err = kernel_getsockname(newsock, sin, &slen); if (unlikely(err < 0)) { dprintk("svc_tcp_accept: kernel_getsockname error %d\n", -err); slen = offsetof(struct sockaddr, sa_data); } memcpy(&newsvsk->sk_local, sin, slen); svc_sock_received(newsvsk); /* 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. */ 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); printk(KERN_NOTICE "%s: last TCP connect from %s\n", serv->sv_name, __svc_print_addr(sin, buf, sizeof(buf))); } /* * 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); } } if (serv->sv_stats) serv->sv_stats->nettcpconn++; return &newsvsk->sk_xprt; failed: sock_release(newsock); return NULL; } /* * Receive data from a TCP socket. */ static int svc_tcp_recvfrom(struct svc_rqst *rqstp) { struct svc_sock *svsk = rqstp->rq_sock; struct svc_serv *serv = svsk->sk_server; int len; struct kvec *vec; int pnum, vlen; dprintk("svc: tcp_recv %p data %d conn %d close %d\n", svsk, test_bit(SK_DATA, &svsk->sk_flags), test_bit(SK_CONN, &svsk->sk_flags), test_bit(SK_CLOSE, &svsk->sk_flags)); if ((rqstp->rq_deferred = svc_deferred_dequeue(svsk))) { svc_sock_received(svsk); return svc_deferred_recv(rqstp); } if (test_and_clear_bit(SK_CHNGBUF, &svsk->sk_flags)) /* sndbuf needs to have room for one request * per thread, otherwise we can stall even when the * network isn't a bottleneck. * * We count all threads rather than threads in a * particular pool, which provides an upper bound * on the number of threads which will access the socket. * * rcvbuf just needs to be able to hold a few requests. * Normally they will be removed from the queue * as soon a a complete request arrives. */ svc_sock_setbufsize(svsk->sk_sock, (serv->sv_nrthreads+3) * serv->sv_max_mesg, 3 * serv->sv_max_mesg); clear_bit(SK_DATA, &svsk->sk_flags); /* Receive data. If we haven't got the record length yet, get * the next four bytes. Otherwise try to gobble up as much as * possible up to the complete record length. */ if (svsk->sk_tcplen < 4) { unsigned long want = 4 - svsk->sk_tcplen; struct kvec iov; iov.iov_base = ((char *) &svsk->sk_reclen) + svsk->sk_tcplen; iov.iov_len = want; if ((len = svc_recvfrom(rqstp, &iov, 1, want)) < 0) goto error; svsk->sk_tcplen += len; if (len < want) { dprintk("svc: short recvfrom while reading record length (%d of %lu)\n", len, want); svc_sock_received(svsk); return -EAGAIN; /* record header not complete */ } svsk->sk_reclen = ntohl(svsk->sk_reclen); if (!(svsk->sk_reclen & 0x80000000)) { /* FIXME: technically, a record can be fragmented, * and non-terminal fragments will not have the top * bit set in the fragment length header. * But apparently no known nfs clients send fragmented * records. */ if (net_ratelimit()) printk(KERN_NOTICE "RPC: bad TCP reclen 0x%08lx" " (non-terminal)\n", (unsigned long) svsk->sk_reclen); goto err_delete; } svsk->sk_reclen &= 0x7fffffff; dprintk("svc: TCP record, %d bytes\n", svsk->sk_reclen); if (svsk->sk_reclen > serv->sv_max_mesg) { if (net_ratelimit()) printk(KERN_NOTICE "RPC: bad TCP reclen 0x%08lx" " (large)\n", (unsigned long) svsk->sk_reclen); goto err_delete; } } /* Check whether enough data is available */ len = svc_recv_available(svsk); if (len < 0) goto error; if (len < svsk->sk_reclen) { dprintk("svc: incomplete TCP record (%d of %d)\n", len, svsk->sk_reclen); svc_sock_received(svsk); return -EAGAIN; /* record not complete */ } len = svsk->sk_reclen; set_bit(SK_DATA, &svsk->sk_flags); vec = rqstp->rq_vec; vec[0] = rqstp->rq_arg.head[0]; vlen = PAGE_SIZE; pnum = 1; while (vlen < len) { vec[pnum].iov_base = page_address(rqstp->rq_pages[pnum]); vec[pnum].iov_len = PAGE_SIZE; pnum++; vlen += PAGE_SIZE; } rqstp->rq_respages = &rqstp->rq_pages[pnum]; /* Now receive data */ len = svc_recvfrom(rqstp, vec, pnum, len); if (len < 0) goto error; dprintk("svc: TCP complete record (%d bytes)\n", len); rqstp->rq_arg.len = len; rqstp->rq_arg.page_base = 0; if (len <= rqstp->rq_arg.head[0].iov_len) { rqstp->rq_arg.head[0].iov_len = len; rqstp->rq_arg.page_len = 0; } else { rqstp->rq_arg.page_len = len - rqstp->rq_arg.head[0].iov_len; } rqstp->rq_xprt_ctxt = NULL; rqstp->rq_prot = IPPROTO_TCP; /* Reset TCP read info */ svsk->sk_reclen = 0; svsk->sk_tcplen = 0; svc_sock_received(svsk); if (serv->sv_stats) serv->sv_stats->nettcpcnt++; return len; err_delete: set_bit(SK_CLOSE, &svsk->sk_flags); return -EAGAIN; error: if (len == -EAGAIN) { dprintk("RPC: TCP recvfrom got EAGAIN\n"); svc_sock_received(svsk); } else { printk(KERN_NOTICE "%s: recvfrom returned errno %d\n", svsk->sk_server->sv_name, -len); goto err_delete; } return len; } /* * Send out data on TCP socket. */ static int svc_tcp_sendto(struct svc_rqst *rqstp) { struct xdr_buf *xbufp = &rqstp->rq_res; int sent; __be32 reclen; /* Set up the first element of the reply kvec. * Any other kvecs that may be in use have been taken * care of by the server implementation itself. */ reclen = htonl(0x80000000|((xbufp->len ) - 4)); memcpy(xbufp->head[0].iov_base, &reclen, 4); if (test_bit(SK_DEAD, &rqstp->rq_sock->sk_flags)) return -ENOTCONN; 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", rqstp->rq_sock->sk_server->sv_name, (sent<0)?"got error":"sent only", sent, xbufp->len); set_bit(SK_CLOSE, &rqstp->rq_sock->sk_flags); svc_sock_enqueue(rqstp->rq_sock); sent = -EAGAIN; } return sent; } /* * Setup response header. TCP has a 4B record length field. */ static void svc_tcp_prep_reply_hdr(struct svc_rqst *rqstp) { struct kvec *resv = &rqstp->rq_res.head[0]; /* tcp needs a space for the record length... */ svc_putnl(resv, 0); } static int svc_tcp_has_wspace(struct svc_xprt *xprt) { struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); struct svc_serv *serv = svsk->sk_server; int required; int wspace; /* * Set the SOCK_NOSPACE flag before checking the available * sock space. */ set_bit(SOCK_NOSPACE, &svsk->sk_sock->flags); required = atomic_read(&svsk->sk_reserved) + serv->sv_max_mesg; wspace = sk_stream_wspace(svsk->sk_sk); if (wspace < sk_stream_min_wspace(svsk->sk_sk)) return 0; if (required * 2 > wspace) return 0; clear_bit(SOCK_NOSPACE, &svsk->sk_sock->flags); return 1; } static struct svc_xprt_ops svc_tcp_ops = { .xpo_recvfrom = svc_tcp_recvfrom, .xpo_sendto = svc_tcp_sendto, .xpo_release_rqst = svc_release_skb, .xpo_detach = svc_sock_detach, .xpo_free = svc_sock_free, .xpo_prep_reply_hdr = svc_tcp_prep_reply_hdr, .xpo_has_wspace = svc_tcp_has_wspace, .xpo_accept = svc_tcp_accept, }; static struct svc_xprt_class svc_tcp_class = { .xcl_name = "tcp", .xcl_ops = &svc_tcp_ops, .xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP, }; void svc_init_xprt_sock(void) { svc_reg_xprt_class(&svc_tcp_class); svc_reg_xprt_class(&svc_udp_class); } void svc_cleanup_xprt_sock(void) { svc_unreg_xprt_class(&svc_tcp_class); svc_unreg_xprt_class(&svc_udp_class); } static void svc_tcp_init(struct svc_sock *svsk) { struct sock *sk = svsk->sk_sk; struct tcp_sock *tp = tcp_sk(sk); svc_xprt_init(&svc_tcp_class, &svsk->sk_xprt); if (sk->sk_state == TCP_LISTEN) { dprintk("setting up TCP socket for listening\n"); set_bit(SK_LISTENER, &svsk->sk_flags); sk->sk_data_ready = svc_tcp_listen_data_ready; set_bit(SK_CONN, &svsk->sk_flags); } else { dprintk("setting up TCP socket for reading\n"); sk->sk_state_change = svc_tcp_state_change; sk->sk_data_ready = svc_tcp_data_ready; sk->sk_write_space = svc_write_space; svsk->sk_reclen = 0; svsk->sk_tcplen = 0; tp->nonagle = 1; /* disable Nagle's algorithm */ /* initialise setting must have enough space to * receive and respond to one request. * svc_tcp_recvfrom will re-adjust if necessary */ svc_sock_setbufsize(svsk->sk_sock, 3 * svsk->sk_server->sv_max_mesg, 3 * svsk->sk_server->sv_max_mesg); set_bit(SK_CHNGBUF, &svsk->sk_flags); set_bit(SK_DATA, &svsk->sk_flags); if (sk->sk_state != TCP_ESTABLISHED) set_bit(SK_CLOSE, &svsk->sk_flags); } } void svc_sock_update_bufs(struct svc_serv *serv) { /* * The number of server threads has changed. Update * rcvbuf and sndbuf accordingly on all sockets */ struct list_head *le; spin_lock_bh(&serv->sv_lock); list_for_each(le, &serv->sv_permsocks) { struct svc_sock *svsk = list_entry(le, struct svc_sock, sk_list); set_bit(SK_CHNGBUF, &svsk->sk_flags); } list_for_each(le, &serv->sv_tempsocks) { struct svc_sock *svsk = list_entry(le, struct svc_sock, sk_list); set_bit(SK_CHNGBUF, &svsk->sk_flags); } spin_unlock_bh(&serv->sv_lock); } /* * 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_sock *svsk = 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_sock) printk(KERN_ERR "svc_recv: service %p, socket 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); if ((svsk = svc_sock_dequeue(pool)) != NULL) { rqstp->rq_sock = svsk; atomic_inc(&svsk->sk_inuse); rqstp->rq_reserved = serv->sv_max_mesg; atomic_add(rqstp->rq_reserved, &svsk->sk_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); if (!(svsk = rqstp->rq_sock)) { 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(SK_CLOSE, &svsk->sk_flags)) { dprintk("svc_recv: found SK_CLOSE\n"); svc_delete_socket(svsk); } else if (test_bit(SK_LISTENER, &svsk->sk_flags)) { struct svc_xprt *newxpt; newxpt = svsk->sk_xprt.xpt_ops->xpo_accept(&svsk->sk_xprt); 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)); len = svsk->sk_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_sock_release(rqstp); return -EAGAIN; } svsk->sk_lastrecv = get_seconds(); clear_bit(SK_OLD, &svsk->sk_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: socket %p dropped request\n", rqstp->rq_sock); svc_sock_release(rqstp); } /* * Return reply to client. */ int svc_send(struct svc_rqst *rqstp) { struct svc_sock *svsk; int len; struct xdr_buf *xb; if ((svsk = rqstp->rq_sock) == NULL) { printk(KERN_WARNING "NULL socket pointer in %s:%d\n", __FILE__, __LINE__); 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 svsk->sk_mutex to serialize outgoing data. */ mutex_lock(&svsk->sk_mutex); if (test_bit(SK_DEAD, &svsk->sk_flags)) len = -ENOTCONN; else len = svsk->sk_xprt.xpt_ops->xpo_sendto(rqstp); mutex_unlock(&svsk->sk_mutex); svc_sock_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_sockets(unsigned long closure) { struct svc_serv *serv = (struct svc_serv *)closure; struct svc_sock *svsk; struct list_head *le, *next; LIST_HEAD(to_be_aged); dprintk("svc_age_temp_sockets\n"); if (!spin_trylock_bh(&serv->sv_lock)) { /* busy, try again 1 sec later */ dprintk("svc_age_temp_sockets: busy\n"); mod_timer(&serv->sv_temptimer, jiffies + HZ); return; } list_for_each_safe(le, next, &serv->sv_tempsocks) { svsk = list_entry(le, struct svc_sock, sk_list); 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)) continue; atomic_inc(&svsk->sk_inuse); list_move(le, &to_be_aged); set_bit(SK_CLOSE, &svsk->sk_flags); set_bit(SK_DETACHED, &svsk->sk_flags); } spin_unlock_bh(&serv->sv_lock); while (!list_empty(&to_be_aged)) { le = to_be_aged.next; /* fiddling the sk_list node is safe 'cos we're SK_DETACHED */ list_del_init(le); svsk = list_entry(le, struct svc_sock, sk_list); dprintk("queuing svsk %p for closing, %lu seconds old\n", svsk, get_seconds() - svsk->sk_lastrecv); /* a thread will dequeue and close it soon */ svc_sock_enqueue(svsk); svc_sock_put(svsk); } 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. */ static struct svc_sock *svc_setup_socket(struct svc_serv *serv, struct socket *sock, int *errp, int flags) { struct svc_sock *svsk; struct sock *inet; int pmap_register = !(flags & SVC_SOCK_ANONYMOUS); int is_temporary = flags & SVC_SOCK_TEMPORARY; dprintk("svc: svc_setup_socket %p\n", sock); if (!(svsk = kzalloc(sizeof(*svsk), GFP_KERNEL))) { *errp = -ENOMEM; return NULL; } inet = sock->sk; /* Register socket with portmapper */ if (*errp >= 0 && pmap_register) *errp = svc_register(serv, inet->sk_protocol, ntohs(inet_sk(inet)->sport)); if (*errp < 0) { kfree(svsk); return NULL; } set_bit(SK_BUSY, &svsk->sk_flags); inet->sk_user_data = svsk; svsk->sk_sock = sock; svsk->sk_sk = inet; svsk->sk_ostate = inet->sk_state_change; 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); INIT_LIST_HEAD(&svsk->sk_ready); mutex_init(&svsk->sk_mutex); /* Initialize the socket */ if (sock->type == SOCK_DGRAM) svc_udp_init(svsk); else svc_tcp_init(svsk); spin_lock_bh(&serv->sv_lock); if (is_temporary) { set_bit(SK_TEMP, &svsk->sk_flags); list_add(&svsk->sk_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_sockets, (unsigned long)serv); mod_timer(&serv->sv_temptimer, jiffies + svc_conn_age_period * HZ); } } else { clear_bit(SK_TEMP, &svsk->sk_flags); list_add(&svsk->sk_list, &serv->sv_permsocks); } spin_unlock_bh(&serv->sv_lock); dprintk("svc: svc_setup_socket created %p (inet %p)\n", svsk, svsk->sk_sk); return svsk; } int svc_addsock(struct svc_serv *serv, int fd, char *name_return, int *proto) { int err = 0; struct socket *so = sockfd_lookup(fd, &err); struct svc_sock *svsk = NULL; if (!so) return err; if (so->sk->sk_family != AF_INET) err = -EAFNOSUPPORT; else if (so->sk->sk_protocol != IPPROTO_TCP && so->sk->sk_protocol != IPPROTO_UDP) err = -EPROTONOSUPPORT; else if (so->state > SS_UNCONNECTED) err = -EISCONN; else { svsk = svc_setup_socket(serv, so, &err, SVC_SOCK_DEFAULTS); if (svsk) { svc_sock_received(svsk); err = 0; } } if (err) { sockfd_put(so); return err; } if (proto) *proto = so->sk->sk_protocol; return one_sock_name(name_return, svsk); } EXPORT_SYMBOL_GPL(svc_addsock); /* * Create socket for RPC service. */ static int svc_create_socket(struct svc_serv *serv, int protocol, struct sockaddr *sin, int len, int flags) { struct svc_sock *svsk; struct socket *sock; int error; int type; char buf[RPC_MAX_ADDRBUFLEN]; dprintk("svc: svc_create_socket(%s, %d, %s)\n", serv->sv_program->pg_name, protocol, __svc_print_addr(sin, buf, sizeof(buf))); if (protocol != IPPROTO_UDP && protocol != IPPROTO_TCP) { printk(KERN_WARNING "svc: only UDP and TCP " "sockets supported\n"); return -EINVAL; } type = (protocol == IPPROTO_UDP)? SOCK_DGRAM : SOCK_STREAM; error = sock_create_kern(sin->sa_family, type, protocol, &sock); if (error < 0) return error; svc_reclassify_socket(sock); if (type == SOCK_STREAM) sock->sk->sk_reuse = 1; /* allow address reuse */ error = kernel_bind(sock, sin, len); if (error < 0) goto bummer; if (protocol == IPPROTO_TCP) { if ((error = kernel_listen(sock, 64)) < 0) goto bummer; } if ((svsk = svc_setup_socket(serv, sock, &error, flags)) != NULL) { svc_sock_received(svsk); return ntohs(inet_sk(svsk->sk_sk)->sport); } bummer: dprintk("svc: svc_create_socket error = %d\n", -error); sock_release(sock); return error; } /* * Detach the svc_sock from the socket so that no * more callbacks occur. */ static void svc_sock_detach(struct svc_xprt *xprt) { struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); struct sock *sk = svsk->sk_sk; dprintk("svc: svc_sock_detach(%p)\n", svsk); /* put back the old socket callbacks */ sk->sk_state_change = svsk->sk_ostate; sk->sk_data_ready = svsk->sk_odata; sk->sk_write_space = svsk->sk_owspace; } /* * Free the svc_sock's socket resources and the svc_sock itself. */ static void svc_sock_free(struct svc_xprt *xprt) { struct svc_sock *svsk = container_of(xprt, struct svc_sock, sk_xprt); dprintk("svc: svc_sock_free(%p)\n", svsk); if (svsk->sk_info_authunix != NULL) svcauth_unix_info_release(svsk->sk_info_authunix); if (svsk->sk_sock->file) sockfd_put(svsk->sk_sock); else sock_release(svsk->sk_sock); kfree(svsk); } /* * Remove a dead socket */ static void svc_delete_socket(struct svc_sock *svsk) { struct svc_serv *serv; struct sock *sk; dprintk("svc: svc_delete_socket(%p)\n", svsk); serv = svsk->sk_server; sk = svsk->sk_sk; svsk->sk_xprt.xpt_ops->xpo_detach(&svsk->sk_xprt); spin_lock_bh(&serv->sv_lock); if (!test_and_set_bit(SK_DETACHED, &svsk->sk_flags)) list_del_init(&svsk->sk_list); /* * We used to delete the svc_sock from whichever list * it's sk_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(SK_DEAD, &svsk->sk_flags)) { BUG_ON(atomic_read(&svsk->sk_inuse)<2); atomic_dec(&svsk->sk_inuse); if (test_bit(SK_TEMP, &svsk->sk_flags)) serv->sv_tmpcnt--; } spin_unlock_bh(&serv->sv_lock); } static void svc_close_socket(struct svc_sock *svsk) { set_bit(SK_CLOSE, &svsk->sk_flags); if (test_and_set_bit(SK_BUSY, &svsk->sk_flags)) /* someone else will have to effect the close */ return; atomic_inc(&svsk->sk_inuse); svc_delete_socket(svsk); clear_bit(SK_BUSY, &svsk->sk_flags); svc_sock_put(svsk); } void svc_force_close_socket(struct svc_sock *svsk) { set_bit(SK_CLOSE, &svsk->sk_flags); if (test_bit(SK_BUSY, &svsk->sk_flags)) { /* Waiting to be processed, but no threads left, * So just remove it from the waiting list */ list_del_init(&svsk->sk_ready); clear_bit(SK_BUSY, &svsk->sk_flags); } svc_close_socket(svsk); } /** * svc_makesock - Make a socket for nfsd and lockd * @serv: RPC server structure * @protocol: transport protocol to use * @port: port to use * @flags: requested socket characteristics * */ int svc_makesock(struct svc_serv *serv, int protocol, unsigned short port, int flags) { struct sockaddr_in sin = { .sin_family = AF_INET, .sin_addr.s_addr = INADDR_ANY, .sin_port = htons(port), }; dprintk("svc: creating socket proto = %d\n", protocol); return svc_create_socket(serv, protocol, (struct sockaddr *) &sin, sizeof(sin), flags); } /* * 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_sock *svsk; if (too_many) { svc_sock_put(dr->svsk); kfree(dr); return; } dprintk("revisit queued\n"); svsk = dr->svsk; dr->svsk = NULL; spin_lock(&svsk->sk_lock); list_add(&dr->handle.recent, &svsk->sk_deferred); spin_unlock(&svsk->sk_lock); set_bit(SK_DEFERRED, &svsk->sk_flags); svc_sock_enqueue(svsk); svc_sock_put(svsk); } 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); } atomic_inc(&rqstp->rq_sock->sk_inuse); dr->svsk = rqstp->rq_sock; 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_sock *svsk) { struct svc_deferred_req *dr = NULL; if (!test_bit(SK_DEFERRED, &svsk->sk_flags)) return NULL; spin_lock(&svsk->sk_lock); clear_bit(SK_DEFERRED, &svsk->sk_flags); if (!list_empty(&svsk->sk_deferred)) { dr = list_entry(svsk->sk_deferred.next, struct svc_deferred_req, handle.recent); list_del_init(&dr->handle.recent); set_bit(SK_DEFERRED, &svsk->sk_flags); } spin_unlock(&svsk->sk_lock); return dr; }