/* * Discard a packet we've used up and advance the Rx window by one. */ static void rxrpc_rotate_rx_window(struct rxrpc_call *call) { struct rxrpc_skb_priv *sp; struct sk_buff *skb; rxrpc_serial_t serial; rxrpc_seq_t hard_ack, top; u8 flags; int ix; _enter("%d", call->debug_id); hard_ack = call->rx_hard_ack; top = smp_load_acquire(&call->rx_top); ASSERT(before(hard_ack, top)); hard_ack++; ix = hard_ack & RXRPC_RXTX_BUFF_MASK; skb = call->rxtx_buffer[ix]; rxrpc_see_skb(skb, rxrpc_skb_rx_rotated); sp = rxrpc_skb(skb); flags = sp->hdr.flags; serial = sp->hdr.serial; if (call->rxtx_annotations[ix] & RXRPC_RX_ANNO_JUMBO) serial += (call->rxtx_annotations[ix] & RXRPC_RX_ANNO_JUMBO) - 1; call->rxtx_buffer[ix] = NULL; call->rxtx_annotations[ix] = 0; /* Barrier against rxrpc_input_data(). */ smp_store_release(&call->rx_hard_ack, hard_ack); rxrpc_free_skb(skb, rxrpc_skb_rx_freed); _debug("%u,%u,%02x", hard_ack, top, flags); trace_rxrpc_receive(call, rxrpc_receive_rotate, serial, hard_ack); if (flags & RXRPC_LAST_PACKET) { rxrpc_end_rx_phase(call, serial); } else { /* Check to see if there's an ACK that needs sending. */ if (after_eq(hard_ack, call->ackr_consumed + 2) || after_eq(top, call->ackr_seen + 2) || (hard_ack == top && after(hard_ack, call->ackr_consumed))) rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, 0, serial, true, false, rxrpc_propose_ack_rotate_rx); if (call->ackr_reason) rxrpc_send_call_packet(call, RXRPC_PACKET_TYPE_ACK); } }
/* * queue a packet for recvmsg to pass to userspace * - the caller must hold a lock on call->lock * - must not be called with interrupts disabled (sk_filter() disables BH's) * - eats the packet whether successful or not * - there must be just one reference to the packet, which the caller passes to * this function */ int rxrpc_queue_rcv_skb(struct rxrpc_call *call, struct sk_buff *skb, bool force, bool terminal) { struct rxrpc_skb_priv *sp; struct rxrpc_sock *rx = call->socket; struct sock *sk; int ret; _enter(",,%d,%d", force, terminal); ASSERT(!irqs_disabled()); sp = rxrpc_skb(skb); ASSERTCMP(sp->call, ==, call); /* if we've already posted the terminal message for a call, then we * don't post any more */ if (test_bit(RXRPC_CALL_TERMINAL_MSG, &call->flags)) { _debug("already terminated"); ASSERTCMP(call->state, >=, RXRPC_CALL_COMPLETE); rxrpc_free_skb(skb); return 0; }
int rxrpc_queue_rcv_skb(struct rxrpc_call *call, struct sk_buff *skb, bool force, bool terminal) { struct rxrpc_skb_priv *sp; struct rxrpc_sock *rx = call->socket; struct sock *sk; int skb_len, ret; _enter(",,%d,%d", force, terminal); ASSERT(!irqs_disabled()); sp = rxrpc_skb(skb); ASSERTCMP(sp->call, ==, call); if (test_bit(RXRPC_CALL_TERMINAL_MSG, &call->flags)) { _debug("already terminated"); ASSERTCMP(call->state, >=, RXRPC_CALL_COMPLETE); skb->destructor = NULL; sp->call = NULL; rxrpc_put_call(call); rxrpc_free_skb(skb); return 0; }
/* * handle an error received on the local endpoint */ void rxrpc_UDP_error_report(struct sock *sk) { struct sock_exterr_skb *serr; struct rxrpc_transport *trans; struct rxrpc_local *local = sk->sk_user_data; struct rxrpc_peer *peer; struct sk_buff *skb; __be32 addr; __be16 port; _enter("%p{%d}", sk, local->debug_id); skb = skb_dequeue(&sk->sk_error_queue); if (!skb) { _leave("UDP socket errqueue empty"); return; } rxrpc_new_skb(skb); serr = SKB_EXT_ERR(skb); addr = *(__be32 *)(skb_network_header(skb) + serr->addr_offset); port = serr->port; _net("Rx UDP Error from "NIPQUAD_FMT":%hu", NIPQUAD(addr), ntohs(port)); _debug("Msg l:%d d:%d", skb->len, skb->data_len); peer = rxrpc_find_peer(local, addr, port); if (IS_ERR(peer)) { rxrpc_free_skb(skb); _leave(" [no peer]"); return; } trans = rxrpc_find_transport(local, peer); if (!trans) { rxrpc_put_peer(peer); rxrpc_free_skb(skb); _leave(" [no trans]"); return; } if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP && serr->ee.ee_type == ICMP_DEST_UNREACH && serr->ee.ee_code == ICMP_FRAG_NEEDED ) { u32 mtu = serr->ee.ee_info; _net("Rx Received ICMP Fragmentation Needed (%d)", mtu); /* wind down the local interface MTU */ if (mtu > 0 && peer->if_mtu == 65535 && mtu < peer->if_mtu) { peer->if_mtu = mtu; _net("I/F MTU %u", mtu); } /* ip_rt_frag_needed() may have eaten the info */ if (mtu == 0) mtu = ntohs(icmp_hdr(skb)->un.frag.mtu); if (mtu == 0) { /* they didn't give us a size, estimate one */ if (mtu > 1500) { mtu >>= 1; if (mtu < 1500) mtu = 1500; } else {
/* * receive a message from an RxRPC socket * - we need to be careful about two or more threads calling recvmsg * simultaneously */ 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) { size_t len = sizeof(call->conn->trans->peer->srx); memcpy(msg->msg_name, &call->conn->trans->peer->srx, len); msg->msg_namelen = len; } 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; ret = skb_copy_datagram_iovec(skb, offset, msg->msg_iov, copy); 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); }
void rxrpc_reject_packets(struct work_struct *work) { union { struct sockaddr sa; struct sockaddr_in sin; } sa; struct rxrpc_skb_priv *sp; struct rxrpc_header hdr; struct rxrpc_local *local; struct sk_buff *skb; struct msghdr msg; struct kvec iov[2]; size_t size; __be32 code; local = container_of(work, struct rxrpc_local, rejecter); rxrpc_get_local(local); _enter("%d", local->debug_id); iov[0].iov_base = &hdr; iov[0].iov_len = sizeof(hdr); iov[1].iov_base = &code; iov[1].iov_len = sizeof(code); size = sizeof(hdr) + sizeof(code); msg.msg_name = &sa; msg.msg_control = NULL; msg.msg_controllen = 0; msg.msg_flags = 0; memset(&sa, 0, sizeof(sa)); sa.sa.sa_family = local->srx.transport.family; switch (sa.sa.sa_family) { case AF_INET: msg.msg_namelen = sizeof(sa.sin); break; default: msg.msg_namelen = 0; break; } memset(&hdr, 0, sizeof(hdr)); hdr.type = RXRPC_PACKET_TYPE_ABORT; while ((skb = skb_dequeue(&local->reject_queue))) { sp = rxrpc_skb(skb); switch (sa.sa.sa_family) { case AF_INET: sa.sin.sin_port = udp_hdr(skb)->source; sa.sin.sin_addr.s_addr = ip_hdr(skb)->saddr; code = htonl(skb->priority); hdr.epoch = sp->hdr.epoch; hdr.cid = sp->hdr.cid; hdr.callNumber = sp->hdr.callNumber; hdr.serviceId = sp->hdr.serviceId; hdr.flags = sp->hdr.flags; hdr.flags ^= RXRPC_CLIENT_INITIATED; hdr.flags &= RXRPC_CLIENT_INITIATED; kernel_sendmsg(local->socket, &msg, iov, 2, size); break; default: break; } rxrpc_free_skb(skb); rxrpc_put_local(local); } rxrpc_put_local(local); _leave(""); }
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 (;;) { 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; } } skb = skb_peek(&rx->sk.sk_receive_queue); if (!skb) { if (copied && (msg->msg_flags & MSG_PEEK || timeo == 0)) goto out; 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]); 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; } 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); 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); } 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) { 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; _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; } if (sp->hdr.flags & RXRPC_LAST_PACKET) { _debug("last"); if (call->conn->out_clientflag) { ret = copied; goto terminal_message; } 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; } _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); }
/* * Perform retransmission of NAK'd and unack'd packets. */ static void rxrpc_resend(struct rxrpc_call *call, ktime_t now) { struct rxrpc_skb_priv *sp; struct sk_buff *skb; rxrpc_seq_t cursor, seq, top; ktime_t max_age, oldest, ack_ts; int ix; u8 annotation, anno_type, retrans = 0, unacked = 0; _enter("{%d,%d}", call->tx_hard_ack, call->tx_top); max_age = ktime_sub_ms(now, rxrpc_resend_timeout); spin_lock_bh(&call->lock); cursor = call->tx_hard_ack; top = call->tx_top; ASSERT(before_eq(cursor, top)); if (cursor == top) goto out_unlock; /* Scan the packet list without dropping the lock and decide which of * the packets in the Tx buffer we're going to resend and what the new * resend timeout will be. */ oldest = now; for (seq = cursor + 1; before_eq(seq, top); seq++) { ix = seq & RXRPC_RXTX_BUFF_MASK; annotation = call->rxtx_annotations[ix]; anno_type = annotation & RXRPC_TX_ANNO_MASK; annotation &= ~RXRPC_TX_ANNO_MASK; if (anno_type == RXRPC_TX_ANNO_ACK) continue; skb = call->rxtx_buffer[ix]; rxrpc_see_skb(skb, rxrpc_skb_tx_seen); sp = rxrpc_skb(skb); if (anno_type == RXRPC_TX_ANNO_UNACK) { if (ktime_after(skb->tstamp, max_age)) { if (ktime_before(skb->tstamp, oldest)) oldest = skb->tstamp; continue; } if (!(annotation & RXRPC_TX_ANNO_RESENT)) unacked++; } /* Okay, we need to retransmit a packet. */ call->rxtx_annotations[ix] = RXRPC_TX_ANNO_RETRANS | annotation; retrans++; trace_rxrpc_retransmit(call, seq, annotation | anno_type, ktime_to_ns(ktime_sub(skb->tstamp, max_age))); } call->resend_at = ktime_add_ms(oldest, rxrpc_resend_timeout); if (unacked) rxrpc_congestion_timeout(call); /* If there was nothing that needed retransmission then it's likely * that an ACK got lost somewhere. Send a ping to find out instead of * retransmitting data. */ if (!retrans) { rxrpc_set_timer(call, rxrpc_timer_set_for_resend, now); spin_unlock_bh(&call->lock); ack_ts = ktime_sub(now, call->acks_latest_ts); if (ktime_to_ns(ack_ts) < call->peer->rtt) goto out; rxrpc_propose_ACK(call, RXRPC_ACK_PING, 0, 0, true, false, rxrpc_propose_ack_ping_for_lost_ack); rxrpc_send_ack_packet(call, true); goto out; } /* Now go through the Tx window and perform the retransmissions. We * have to drop the lock for each send. If an ACK comes in whilst the * lock is dropped, it may clear some of the retransmission markers for * packets that it soft-ACKs. */ for (seq = cursor + 1; before_eq(seq, top); seq++) { ix = seq & RXRPC_RXTX_BUFF_MASK; annotation = call->rxtx_annotations[ix]; anno_type = annotation & RXRPC_TX_ANNO_MASK; if (anno_type != RXRPC_TX_ANNO_RETRANS) continue; skb = call->rxtx_buffer[ix]; rxrpc_get_skb(skb, rxrpc_skb_tx_got); spin_unlock_bh(&call->lock); if (rxrpc_send_data_packet(call, skb, true) < 0) { rxrpc_free_skb(skb, rxrpc_skb_tx_freed); return; } if (rxrpc_is_client_call(call)) rxrpc_expose_client_call(call); rxrpc_free_skb(skb, rxrpc_skb_tx_freed); spin_lock_bh(&call->lock); /* We need to clear the retransmit state, but there are two * things we need to be aware of: A new ACK/NAK might have been * received and the packet might have been hard-ACK'd (in which * case it will no longer be in the buffer). */ if (after(seq, call->tx_hard_ack)) { annotation = call->rxtx_annotations[ix]; anno_type = annotation & RXRPC_TX_ANNO_MASK; if (anno_type == RXRPC_TX_ANNO_RETRANS || anno_type == RXRPC_TX_ANNO_NAK) { annotation &= ~RXRPC_TX_ANNO_MASK; annotation |= RXRPC_TX_ANNO_UNACK; } annotation |= RXRPC_TX_ANNO_RESENT; call->rxtx_annotations[ix] = annotation; } if (after(call->tx_hard_ack, seq)) seq = call->tx_hard_ack; } out_unlock: spin_unlock_bh(&call->lock); out: _leave(""); }