int rxrpc_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t len, int flags) { struct rxrpc_skb_priv *sp; struct rxrpc_call *call = NULL, *continue_call = NULL; struct rxrpc_sock *rx = rxrpc_sk(sock->sk); struct sk_buff *skb; long timeo; int copy, ret, ullen, offset, copied = 0; u32 abort_code; DEFINE_WAIT(wait); _enter(",,,%zu,%d", len, flags); if (flags & (MSG_OOB | MSG_TRUNC)) return -EOPNOTSUPP; ullen = msg->msg_flags & MSG_CMSG_COMPAT ? 4 : sizeof(unsigned long); timeo = sock_rcvtimeo(&rx->sk, flags & MSG_DONTWAIT); msg->msg_flags |= MSG_MORE; lock_sock(&rx->sk); for (;;) { /* return immediately if a client socket has no outstanding * calls */ if (RB_EMPTY_ROOT(&rx->calls)) { if (copied) goto out; if (rx->sk.sk_state != RXRPC_SERVER_LISTENING) { release_sock(&rx->sk); if (continue_call) rxrpc_put_call(continue_call); return -ENODATA; } } /* get the next message on the Rx queue */ skb = skb_peek(&rx->sk.sk_receive_queue); if (!skb) { /* nothing remains on the queue */ if (copied && (msg->msg_flags & MSG_PEEK || timeo == 0)) goto out; /* wait for a message to turn up */ release_sock(&rx->sk); prepare_to_wait_exclusive(sk_sleep(&rx->sk), &wait, TASK_INTERRUPTIBLE); ret = sock_error(&rx->sk); if (ret) goto wait_error; if (skb_queue_empty(&rx->sk.sk_receive_queue)) { if (signal_pending(current)) goto wait_interrupted; timeo = schedule_timeout(timeo); } finish_wait(sk_sleep(&rx->sk), &wait); lock_sock(&rx->sk); continue; } peek_next_packet: sp = rxrpc_skb(skb); call = sp->call; ASSERT(call != NULL); _debug("next pkt %s", rxrpc_pkts[sp->hdr.type]); /* make sure we wait for the state to be updated in this call */ spin_lock_bh(&call->lock); spin_unlock_bh(&call->lock); if (test_bit(RXRPC_CALL_RELEASED, &call->flags)) { _debug("packet from released call"); if (skb_dequeue(&rx->sk.sk_receive_queue) != skb) BUG(); rxrpc_free_skb(skb); continue; } /* determine whether to continue last data receive */ if (continue_call) { _debug("maybe cont"); if (call != continue_call || skb->mark != RXRPC_SKB_MARK_DATA) { release_sock(&rx->sk); rxrpc_put_call(continue_call); _leave(" = %d [noncont]", copied); return copied; } } rxrpc_get_call(call); /* copy the peer address and timestamp */ if (!continue_call) { if (msg->msg_name && msg->msg_namelen > 0) memcpy(msg->msg_name, &call->conn->trans->peer->srx, sizeof(call->conn->trans->peer->srx)); sock_recv_ts_and_drops(msg, &rx->sk, skb); } /* receive the message */ if (skb->mark != RXRPC_SKB_MARK_DATA) goto receive_non_data_message; _debug("recvmsg DATA #%u { %d, %d }", ntohl(sp->hdr.seq), skb->len, sp->offset); if (!continue_call) { /* only set the control data once per recvmsg() */ ret = put_cmsg(msg, SOL_RXRPC, RXRPC_USER_CALL_ID, ullen, &call->user_call_ID); if (ret < 0) goto copy_error; ASSERT(test_bit(RXRPC_CALL_HAS_USERID, &call->flags)); } ASSERTCMP(ntohl(sp->hdr.seq), >=, call->rx_data_recv); ASSERTCMP(ntohl(sp->hdr.seq), <=, call->rx_data_recv + 1); call->rx_data_recv = ntohl(sp->hdr.seq); ASSERTCMP(ntohl(sp->hdr.seq), >, call->rx_data_eaten); offset = sp->offset; copy = skb->len - offset; if (copy > len - copied) copy = len - copied; if (skb->ip_summed == CHECKSUM_UNNECESSARY) { ret = skb_copy_datagram_iovec(skb, offset, msg->msg_iov, copy); } else { ret = skb_copy_and_csum_datagram_iovec(skb, offset, msg->msg_iov); if (ret == -EINVAL) goto csum_copy_error; } if (ret < 0) goto copy_error; /* handle piecemeal consumption of data packets */ _debug("copied %d+%d", copy, copied); offset += copy; copied += copy; if (!(flags & MSG_PEEK)) sp->offset = offset; if (sp->offset < skb->len) { _debug("buffer full"); ASSERTCMP(copied, ==, len); break; } /* we transferred the whole data packet */ if (sp->hdr.flags & RXRPC_LAST_PACKET) { _debug("last"); if (call->conn->out_clientflag) { /* last byte of reply received */ ret = copied; goto terminal_message; } /* last bit of request received */ if (!(flags & MSG_PEEK)) { _debug("eat packet"); if (skb_dequeue(&rx->sk.sk_receive_queue) != skb) BUG(); rxrpc_free_skb(skb); } msg->msg_flags &= ~MSG_MORE; break; } /* move on to the next data message */ _debug("next"); if (!continue_call) continue_call = sp->call; else rxrpc_put_call(call); call = NULL; if (flags & MSG_PEEK) { _debug("peek next"); skb = skb->next; if (skb == (struct sk_buff *) &rx->sk.sk_receive_queue) break; goto peek_next_packet; } _debug("eat packet"); if (skb_dequeue(&rx->sk.sk_receive_queue) != skb) BUG(); rxrpc_free_skb(skb); }
int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, int len, int noblock, int flags, int *addr_len) { struct sk_buff *skb; int copied, err; if (addr_len) *addr_len=sizeof(struct sockaddr_in6); if (flags & MSG_ERRQUEUE) return ipv6_recv_error(sk, msg, len); skb = skb_recv_datagram(sk, flags, noblock, &err); if (!skb) goto out; copied = skb->len - sizeof(struct udphdr); if (copied > len) { copied = len; msg->msg_flags |= MSG_TRUNC; } if (skb->ip_summed==CHECKSUM_UNNECESSARY) { err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov, copied); } else if (msg->msg_flags&MSG_TRUNC) { if ((unsigned short)csum_fold(skb_checksum(skb, 0, skb->len, skb->csum))) goto csum_copy_err; err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov, copied); } else { err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov); if (err == -EINVAL) goto csum_copy_err; } if (err) goto out_free; sock_recv_timestamp(msg, sk, skb); /* Copy the address. */ if (msg->msg_name) { struct sockaddr_in6 *sin6; sin6 = (struct sockaddr_in6 *) msg->msg_name; sin6->sin6_family = AF_INET6; sin6->sin6_port = skb->h.uh->source; sin6->sin6_flowinfo = 0; sin6->sin6_scope_id = 0; if (skb->protocol == __constant_htons(ETH_P_IP)) { ipv6_addr_set(&sin6->sin6_addr, 0, 0, __constant_htonl(0xffff), skb->nh.iph->saddr); if (sk->protinfo.af_inet.cmsg_flags) ip_cmsg_recv(msg, skb); } else { memcpy(&sin6->sin6_addr, &skb->nh.ipv6h->saddr, sizeof(struct in6_addr)); if (sk->net_pinfo.af_inet6.rxopt.all) datagram_recv_ctl(sk, msg, skb); if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) { struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb; sin6->sin6_scope_id = opt->iif; } } } err = copied; out_free: skb_free_datagram(sk, skb); out: return err; csum_copy_err: /* Clear queue. */ if (flags&MSG_PEEK) { int clear = 0; spin_lock_irq(&sk->receive_queue.lock); if (skb == skb_peek(&sk->receive_queue)) { __skb_unlink(skb, &sk->receive_queue); clear = 1; } spin_unlock_irq(&sk->receive_queue.lock); if (clear) kfree_skb(skb); } /* Error for blocking case is chosen to masquerade as some normal condition. */ err = (flags&MSG_DONTWAIT) ? -EAGAIN : -EHOSTUNREACH; UDP6_INC_STATS_USER(UdpInErrors); goto out_free; }