[linux-2.6-block.git] / net / rxrpc / output.c

/* RxRPC packet transmission
 *
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/net.h>
#include <linux/gfp.h>
#include <linux/skbuff.h>
#include <linux/export.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include "ar-internal.h"

struct rxrpc_ack_buffer {
	struct rxrpc_wire_header whdr;
	struct rxrpc_ackpacket ack;
	u8 acks[255];
	u8 pad[3];
	struct rxrpc_ackinfo ackinfo;
};

struct rxrpc_abort_buffer {
	struct rxrpc_wire_header whdr;
	__be32 abort_code;
};

static const char rxrpc_keepalive_string[] = "";

/*
 * Arrange for a keepalive ping a certain time after we last transmitted.  This
 * lets the far side know we're still interested in this call and helps keep
 * the route through any intervening firewall open.
 *
 * Receiving a response to the ping will prevent the ->expect_rx_by timer from
 * expiring.
 */
static void rxrpc_set_keepalive(struct rxrpc_call *call)
{
	unsigned long now = jiffies, keepalive_at = call->next_rx_timo / 6;

	keepalive_at += now;
	WRITE_ONCE(call->keepalive_at, keepalive_at);
	rxrpc_reduce_call_timer(call, keepalive_at, now,
				rxrpc_timer_set_for_keepalive);
}

/*
 * Fill out an ACK packet.
 */
static size_t rxrpc_fill_out_ack(struct rxrpc_connection *conn,
				 struct rxrpc_call *call,
				 struct rxrpc_ack_buffer *pkt,
				 rxrpc_seq_t *_hard_ack,
				 rxrpc_seq_t *_top,
				 u8 reason)
{
	rxrpc_serial_t serial;
	rxrpc_seq_t hard_ack, top, seq;
	int ix;
	u32 mtu, jmax;
	u8 *ackp = pkt->acks;

	/* Barrier against rxrpc_input_data(). */
	serial = call->ackr_serial;
	hard_ack = READ_ONCE(call->rx_hard_ack);
	top = smp_load_acquire(&call->rx_top);
	*_hard_ack = hard_ack;
	*_top = top;

	pkt->ack.bufferSpace	= htons(8);
	pkt->ack.maxSkew	= htons(call->ackr_skew);
	pkt->ack.firstPacket	= htonl(hard_ack + 1);
	pkt->ack.previousPacket	= htonl(call->ackr_prev_seq);
	pkt->ack.serial		= htonl(serial);
	pkt->ack.reason		= reason;
	pkt->ack.nAcks		= top - hard_ack;

	if (reason == RXRPC_ACK_PING)
		pkt->whdr.flags |= RXRPC_REQUEST_ACK;

	if (after(top, hard_ack)) {
		seq = hard_ack + 1;
		do {
			ix = seq & RXRPC_RXTX_BUFF_MASK;
			if (call->rxtx_buffer[ix])
				*ackp++ = RXRPC_ACK_TYPE_ACK;
			else
				*ackp++ = RXRPC_ACK_TYPE_NACK;
			seq++;
		} while (before_eq(seq, top));
	}

	mtu = conn->params.peer->if_mtu;
	mtu -= conn->params.peer->hdrsize;
	jmax = (call->nr_jumbo_bad > 3) ? 1 : rxrpc_rx_jumbo_max;
	pkt->ackinfo.rxMTU	= htonl(rxrpc_rx_mtu);
	pkt->ackinfo.maxMTU	= htonl(mtu);
	pkt->ackinfo.rwind	= htonl(call->rx_winsize);
	pkt->ackinfo.jumbo_max	= htonl(jmax);

	*ackp++ = 0;
	*ackp++ = 0;
	*ackp++ = 0;
	return top - hard_ack + 3;
}

/*
 * Send an ACK call packet.
 */
int rxrpc_send_ack_packet(struct rxrpc_call *call, bool ping,
			  rxrpc_serial_t *_serial)
{
	struct rxrpc_connection *conn = NULL;
	struct rxrpc_ack_buffer *pkt;
	struct msghdr msg;
	struct kvec iov[2];
	rxrpc_serial_t serial;
	rxrpc_seq_t hard_ack, top;
	ktime_t now;
	size_t len, n;
	int ret;
	u8 reason;

	spin_lock_bh(&call->lock);
	if (call->conn)
		conn = rxrpc_get_connection_maybe(call->conn);
	spin_unlock_bh(&call->lock);
	if (!conn)
		return -ECONNRESET;

	pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
	if (!pkt) {
		rxrpc_put_connection(conn);
		return -ENOMEM;
	}

	msg.msg_name	= &call->peer->srx.transport;
	msg.msg_namelen	= call->peer->srx.transport_len;
	msg.msg_control	= NULL;
	msg.msg_controllen = 0;
	msg.msg_flags	= 0;

	pkt->whdr.epoch		= htonl(conn->proto.epoch);
	pkt->whdr.cid		= htonl(call->cid);
	pkt->whdr.callNumber	= htonl(call->call_id);
	pkt->whdr.seq		= 0;
	pkt->whdr.type		= RXRPC_PACKET_TYPE_ACK;
	pkt->whdr.flags		= RXRPC_SLOW_START_OK | conn->out_clientflag;
	pkt->whdr.userStatus	= 0;
	pkt->whdr.securityIndex	= call->security_ix;
	pkt->whdr._rsvd		= 0;
	pkt->whdr.serviceId	= htons(call->service_id);

	spin_lock_bh(&call->lock);
	if (ping) {
		reason = RXRPC_ACK_PING;
	} else {
		reason = call->ackr_reason;
		if (!call->ackr_reason) {
			spin_unlock_bh(&call->lock);
			ret = 0;
			goto out;
		}
		call->ackr_reason = 0;
	}
	n = rxrpc_fill_out_ack(conn, call, pkt, &hard_ack, &top, reason);

	spin_unlock_bh(&call->lock);

	iov[0].iov_base	= pkt;
	iov[0].iov_len	= sizeof(pkt->whdr) + sizeof(pkt->ack) + n;
	iov[1].iov_base = &pkt->ackinfo;
	iov[1].iov_len	= sizeof(pkt->ackinfo);
	len = iov[0].iov_len + iov[1].iov_len;

	serial = atomic_inc_return(&conn->serial);
	pkt->whdr.serial = htonl(serial);
	trace_rxrpc_tx_ack(call->debug_id, serial,
			   ntohl(pkt->ack.firstPacket),
			   ntohl(pkt->ack.serial),
			   pkt->ack.reason, pkt->ack.nAcks);
	if (_serial)
		*_serial = serial;

	if (ping) {
		call->ping_serial = serial;
		smp_wmb();
		/* We need to stick a time in before we send the packet in case
		 * the reply gets back before kernel_sendmsg() completes - but
		 * asking UDP to send the packet can take a relatively long
		 * time, so we update the time after, on the assumption that
		 * the packet transmission is more likely to happen towards the
		 * end of the kernel_sendmsg() call.
		 */
		call->ping_time = ktime_get_real();
		set_bit(RXRPC_CALL_PINGING, &call->flags);
		trace_rxrpc_rtt_tx(call, rxrpc_rtt_tx_ping, serial);
	}

	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
	now = ktime_get_real();
	if (ping)
		call->ping_time = now;
	conn->params.peer->last_tx_at = ktime_get_seconds();
	if (ret < 0)
		trace_rxrpc_tx_fail(call->debug_id, serial, ret,
				    rxrpc_tx_point_call_ack);
	else
		trace_rxrpc_tx_packet(call->debug_id, &pkt->whdr,
				      rxrpc_tx_point_call_ack);

	if (call->state < RXRPC_CALL_COMPLETE) {
		if (ret < 0) {
			if (ping)
				clear_bit(RXRPC_CALL_PINGING, &call->flags);
			rxrpc_propose_ACK(call, pkt->ack.reason,
					  ntohs(pkt->ack.maxSkew),
					  ntohl(pkt->ack.serial),
					  true, true,
					  rxrpc_propose_ack_retry_tx);
		} else {
			spin_lock_bh(&call->lock);
			if (after(hard_ack, call->ackr_consumed))
				call->ackr_consumed = hard_ack;
			if (after(top, call->ackr_seen))
				call->ackr_seen = top;
			spin_unlock_bh(&call->lock);
		}

		rxrpc_set_keepalive(call);
	}

out:
	rxrpc_put_connection(conn);
	kfree(pkt);
	return ret;
}

/*
 * Send an ABORT call packet.
 */
int rxrpc_send_abort_packet(struct rxrpc_call *call)
{
	struct rxrpc_connection *conn = NULL;
	struct rxrpc_abort_buffer pkt;
	struct msghdr msg;
	struct kvec iov[1];
	rxrpc_serial_t serial;
	int ret;

	/* Don't bother sending aborts for a client call once the server has
	 * hard-ACK'd all of its request data.  After that point, we're not
	 * going to stop the operation proceeding, and whilst we might limit
	 * the reply, it's not worth it if we can send a new call on the same
	 * channel instead, thereby closing off this call.
	 */
	if (rxrpc_is_client_call(call) &&
	    test_bit(RXRPC_CALL_TX_LAST, &call->flags))
		return 0;

	spin_lock_bh(&call->lock);
	if (call->conn)
		conn = rxrpc_get_connection_maybe(call->conn);
	spin_unlock_bh(&call->lock);
	if (!conn)
		return -ECONNRESET;

	msg.msg_name	= &call->peer->srx.transport;
	msg.msg_namelen	= call->peer->srx.transport_len;
	msg.msg_control	= NULL;
	msg.msg_controllen = 0;
	msg.msg_flags	= 0;

	pkt.whdr.epoch		= htonl(conn->proto.epoch);
	pkt.whdr.cid		= htonl(call->cid);
	pkt.whdr.callNumber	= htonl(call->call_id);
	pkt.whdr.seq		= 0;
	pkt.whdr.type		= RXRPC_PACKET_TYPE_ABORT;
	pkt.whdr.flags		= conn->out_clientflag;
	pkt.whdr.userStatus	= 0;
	pkt.whdr.securityIndex	= call->security_ix;
	pkt.whdr._rsvd		= 0;
	pkt.whdr.serviceId	= htons(call->service_id);
	pkt.abort_code		= htonl(call->abort_code);

	iov[0].iov_base	= &pkt;
	iov[0].iov_len	= sizeof(pkt);

	serial = atomic_inc_return(&conn->serial);
	pkt.whdr.serial = htonl(serial);

	ret = kernel_sendmsg(conn->params.local->socket,
			     &msg, iov, 1, sizeof(pkt));
	conn->params.peer->last_tx_at = ktime_get_seconds();
	if (ret < 0)
		trace_rxrpc_tx_fail(call->debug_id, serial, ret,
				    rxrpc_tx_point_call_abort);
	else
		trace_rxrpc_tx_packet(call->debug_id, &pkt.whdr,
				      rxrpc_tx_point_call_abort);


	rxrpc_put_connection(conn);
	return ret;
}

/*
 * send a packet through the transport endpoint
 */
int rxrpc_send_data_packet(struct rxrpc_call *call, struct sk_buff *skb,
			   bool retrans)
{
	struct rxrpc_connection *conn = call->conn;
	struct rxrpc_wire_header whdr;
	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
	struct msghdr msg;
	struct kvec iov[2];
	rxrpc_serial_t serial;
	size_t len;
	bool lost = false;
	int ret, opt;

	_enter(",{%d}", skb->len);

	/* Each transmission of a Tx packet needs a new serial number */
	serial = atomic_inc_return(&conn->serial);

	whdr.epoch	= htonl(conn->proto.epoch);
	whdr.cid	= htonl(call->cid);
	whdr.callNumber	= htonl(call->call_id);
	whdr.seq	= htonl(sp->hdr.seq);
	whdr.serial	= htonl(serial);
	whdr.type	= RXRPC_PACKET_TYPE_DATA;
	whdr.flags	= sp->hdr.flags;
	whdr.userStatus	= 0;
	whdr.securityIndex = call->security_ix;
	whdr._rsvd	= htons(sp->hdr._rsvd);
	whdr.serviceId	= htons(call->service_id);

	if (test_bit(RXRPC_CONN_PROBING_FOR_UPGRADE, &conn->flags) &&
	    sp->hdr.seq == 1)
		whdr.userStatus	= RXRPC_USERSTATUS_SERVICE_UPGRADE;

	iov[0].iov_base = &whdr;
	iov[0].iov_len = sizeof(whdr);
	iov[1].iov_base = skb->head;
	iov[1].iov_len = skb->len;
	len = iov[0].iov_len + iov[1].iov_len;

	msg.msg_name = &call->peer->srx.transport;
	msg.msg_namelen = call->peer->srx.transport_len;
	msg.msg_control = NULL;
	msg.msg_controllen = 0;
	msg.msg_flags = 0;

	/* If our RTT cache needs working on, request an ACK.  Also request
	 * ACKs if a DATA packet appears to have been lost.
	 */
	if (!(sp->hdr.flags & RXRPC_LAST_PACKET) &&
	    (test_and_clear_bit(RXRPC_CALL_EV_ACK_LOST, &call->events) ||
	     retrans ||
	     call->cong_mode == RXRPC_CALL_SLOW_START ||
	     (call->peer->rtt_usage < 3 && sp->hdr.seq & 1) ||
	     ktime_before(ktime_add_ms(call->peer->rtt_last_req, 1000),
			  ktime_get_real())))
		whdr.flags |= RXRPC_REQUEST_ACK;

	if (IS_ENABLED(CONFIG_AF_RXRPC_INJECT_LOSS)) {
		static int lose;
		if ((lose++ & 7) == 7) {
			ret = 0;
			lost = true;
			goto done;
		}
	}

	_proto("Tx DATA %%%u { #%u }", serial, sp->hdr.seq);

	/* send the packet with the don't fragment bit set if we currently
	 * think it's small enough */
	if (iov[1].iov_len >= call->peer->maxdata)
		goto send_fragmentable;

	down_read(&conn->params.local->defrag_sem);
	/* send the packet by UDP
	 * - returns -EMSGSIZE if UDP would have to fragment the packet
	 *   to go out of the interface
	 *   - in which case, we'll have processed the ICMP error
	 *     message and update the peer record
	 */
	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
	conn->params.peer->last_tx_at = ktime_get_seconds();

	up_read(&conn->params.local->defrag_sem);
	if (ret < 0)
		trace_rxrpc_tx_fail(call->debug_id, serial, ret,
				    rxrpc_tx_point_call_data_nofrag);
	else
		trace_rxrpc_tx_packet(call->debug_id, &whdr,
				      rxrpc_tx_point_call_data_nofrag);
	if (ret == -EMSGSIZE)
		goto send_fragmentable;

done:
	trace_rxrpc_tx_data(call, sp->hdr.seq, serial, whdr.flags,
			    retrans, lost);
	if (ret >= 0) {
		ktime_t now = ktime_get_real();
		skb->tstamp = now;
		smp_wmb();
		sp->hdr.serial = serial;
		if (whdr.flags & RXRPC_REQUEST_ACK) {
			call->peer->rtt_last_req = now;
			trace_rxrpc_rtt_tx(call, rxrpc_rtt_tx_data, serial);
			if (call->peer->rtt_usage > 1) {
				unsigned long nowj = jiffies, ack_lost_at;

				ack_lost_at = nsecs_to_jiffies(2 * call->peer->rtt);
				if (ack_lost_at < 1)
					ack_lost_at = 1;

				ack_lost_at += nowj;
				WRITE_ONCE(call->ack_lost_at, ack_lost_at);
				rxrpc_reduce_call_timer(call, ack_lost_at, nowj,
							rxrpc_timer_set_for_lost_ack);
			}
		}

		if (sp->hdr.seq == 1 &&
		    !test_and_set_bit(RXRPC_CALL_BEGAN_RX_TIMER,
				      &call->flags)) {
			unsigned long nowj = jiffies, expect_rx_by;

			expect_rx_by = nowj + call->next_rx_timo;
			WRITE_ONCE(call->expect_rx_by, expect_rx_by);
			rxrpc_reduce_call_timer(call, expect_rx_by, nowj,
						rxrpc_timer_set_for_normal);
		}
	}

	rxrpc_set_keepalive(call);

	_leave(" = %d [%u]", ret, call->peer->maxdata);
	return ret;

send_fragmentable:
	/* attempt to send this message with fragmentation enabled */
	_debug("send fragment");

	down_write(&conn->params.local->defrag_sem);

	switch (conn->params.local->srx.transport.family) {
	case AF_INET:
		opt = IP_PMTUDISC_DONT;
		ret = kernel_setsockopt(conn->params.local->socket,
					SOL_IP, IP_MTU_DISCOVER,
					(char *)&opt, sizeof(opt));
		if (ret == 0) {
			ret = kernel_sendmsg(conn->params.local->socket, &msg,
					     iov, 2, len);
			conn->params.peer->last_tx_at = ktime_get_seconds();

			opt = IP_PMTUDISC_DO;
			kernel_setsockopt(conn->params.local->socket, SOL_IP,
					  IP_MTU_DISCOVER,
					  (char *)&opt, sizeof(opt));
		}
		break;

#ifdef CONFIG_AF_RXRPC_IPV6
	case AF_INET6:
		opt = IPV6_PMTUDISC_DONT;
		ret = kernel_setsockopt(conn->params.local->socket,
					SOL_IPV6, IPV6_MTU_DISCOVER,
					(char *)&opt, sizeof(opt));
		if (ret == 0) {
			ret = kernel_sendmsg(conn->params.local->socket, &msg,
					     iov, 2, len);
			conn->params.peer->last_tx_at = ktime_get_seconds();

			opt = IPV6_PMTUDISC_DO;
			kernel_setsockopt(conn->params.local->socket,
					  SOL_IPV6, IPV6_MTU_DISCOVER,
					  (char *)&opt, sizeof(opt));
		}
		break;
#endif
	}

	if (ret < 0)
		trace_rxrpc_tx_fail(call->debug_id, serial, ret,
				    rxrpc_tx_point_call_data_frag);
	else
		trace_rxrpc_tx_packet(call->debug_id, &whdr,
				      rxrpc_tx_point_call_data_frag);

	up_write(&conn->params.local->defrag_sem);
	goto done;
}

/*
 * reject packets through the local endpoint
 */
void rxrpc_reject_packets(struct rxrpc_local *local)
{
	struct sockaddr_rxrpc srx;
	struct rxrpc_skb_priv *sp;
	struct rxrpc_wire_header whdr;
	struct sk_buff *skb;
	struct msghdr msg;
	struct kvec iov[2];
	size_t size;
	__be32 code;
	int ret;

	_enter("%d", local->debug_id);

	iov[0].iov_base = &whdr;
	iov[0].iov_len = sizeof(whdr);
	iov[1].iov_base = &code;
	iov[1].iov_len = sizeof(code);
	size = sizeof(whdr) + sizeof(code);

	msg.msg_name = &srx.transport;
	msg.msg_control = NULL;
	msg.msg_controllen = 0;
	msg.msg_flags = 0;

	memset(&whdr, 0, sizeof(whdr));
	whdr.type = RXRPC_PACKET_TYPE_ABORT;

	while ((skb = skb_dequeue(&local->reject_queue))) {
		rxrpc_see_skb(skb, rxrpc_skb_rx_seen);
		sp = rxrpc_skb(skb);

		if (rxrpc_extract_addr_from_skb(local, &srx, skb) == 0) {
			msg.msg_namelen = srx.transport_len;

			code = htonl(skb->priority);

			whdr.epoch	= htonl(sp->hdr.epoch);
			whdr.cid	= htonl(sp->hdr.cid);
			whdr.callNumber	= htonl(sp->hdr.callNumber);
			whdr.serviceId	= htons(sp->hdr.serviceId);
			whdr.flags	= sp->hdr.flags;
			whdr.flags	^= RXRPC_CLIENT_INITIATED;
			whdr.flags	&= RXRPC_CLIENT_INITIATED;

			ret = kernel_sendmsg(local->socket, &msg, iov, 2, size);
			if (ret < 0)
				trace_rxrpc_tx_fail(local->debug_id, 0, ret,
						    rxrpc_tx_point_reject);
			else
				trace_rxrpc_tx_packet(local->debug_id, &whdr,
						      rxrpc_tx_point_reject);
		}

		rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
	}

	_leave("");
}

/*
 * Send a VERSION reply to a peer as a keepalive.
 */
void rxrpc_send_keepalive(struct rxrpc_peer *peer)
{
	struct rxrpc_wire_header whdr;
	struct msghdr msg;
	struct kvec iov[2];
	size_t len;
	int ret;

	_enter("");

	msg.msg_name	= &peer->srx.transport;
	msg.msg_namelen	= peer->srx.transport_len;
	msg.msg_control	= NULL;
	msg.msg_controllen = 0;
	msg.msg_flags	= 0;

	whdr.epoch	= htonl(peer->local->rxnet->epoch);
	whdr.cid	= 0;
	whdr.callNumber	= 0;
	whdr.seq	= 0;
	whdr.serial	= 0;
	whdr.type	= RXRPC_PACKET_TYPE_VERSION; /* Not client-initiated */
	whdr.flags	= RXRPC_LAST_PACKET;
	whdr.userStatus	= 0;
	whdr.securityIndex = 0;
	whdr._rsvd	= 0;
	whdr.serviceId	= 0;

	iov[0].iov_base	= &whdr;
	iov[0].iov_len	= sizeof(whdr);
	iov[1].iov_base	= (char *)rxrpc_keepalive_string;
	iov[1].iov_len	= sizeof(rxrpc_keepalive_string);

	len = iov[0].iov_len + iov[1].iov_len;

	_proto("Tx VERSION (keepalive)");

	ret = kernel_sendmsg(peer->local->socket, &msg, iov, 2, len);
	if (ret < 0)
		trace_rxrpc_tx_fail(peer->debug_id, 0, ret,
				    rxrpc_tx_point_version_keepalive);
	else
		trace_rxrpc_tx_packet(peer->debug_id, &whdr,
				      rxrpc_tx_point_version_keepalive);

	peer->last_tx_at = ktime_get_seconds();
	_leave("");
}
Commit	Line	Data
17926a79 DH	1	/* RxRPC packet transmission
	2	*
	3	* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
	4	* Written by David Howells (dhowells@redhat.com)
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License
	8	* as published by the Free Software Foundation; either version
	9	* 2 of the License, or (at your option) any later version.
	10	*/
	11
9b6d5398 JP	12	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9b6d5398 JP	13
17926a79	14	#include <linux/net.h>
5a0e3ad6	15	#include <linux/gfp.h>
17926a79	16	#include <linux/skbuff.h>
bc3b2d7f	17	#include <linux/export.h>
17926a79 DH	18	#include <net/sock.h>
	19	#include <net/af_rxrpc.h>
	20	#include "ar-internal.h"
	21
26cb02aa	22	struct rxrpc_ack_buffer {
8d94aa38	23	struct rxrpc_wire_header whdr;
26cb02aa DH	24	struct rxrpc_ackpacket ack;
	25	u8 acks[255];
	26	u8 pad[3];
8d94aa38 DH	27	struct rxrpc_ackinfo ackinfo;
	28	};
	29
26cb02aa DH	30	struct rxrpc_abort_buffer {
	31	struct rxrpc_wire_header whdr;
	32	__be32 abort_code;
	33	};
	34
ace45bec DH	35	static const char rxrpc_keepalive_string[] = "";
ace45bec DH	36
415f44e4 DH	37	/*
	38	* Arrange for a keepalive ping a certain time after we last transmitted. This
	39	* lets the far side know we're still interested in this call and helps keep
	40	* the route through any intervening firewall open.
	41	*
	42	* Receiving a response to the ping will prevent the ->expect_rx_by timer from
	43	* expiring.
	44	*/
	45	static void rxrpc_set_keepalive(struct rxrpc_call *call)
	46	{
	47	unsigned long now = jiffies, keepalive_at = call->next_rx_timo / 6;
	48
	49	keepalive_at += now;
	50	WRITE_ONCE(call->keepalive_at, keepalive_at);
	51	rxrpc_reduce_call_timer(call, keepalive_at, now,
	52	rxrpc_timer_set_for_keepalive);
	53	}
	54
8d94aa38 DH	55	/*
	56	* Fill out an ACK packet.
	57	*/
1457cc4c DH	58	static size_t rxrpc_fill_out_ack(struct rxrpc_connection *conn,
1457cc4c DH	59	struct rxrpc_call *call,
26cb02aa	60	struct rxrpc_ack_buffer *pkt,
805b21b9	61	rxrpc_seq_t *_hard_ack,
a5af7e1f DH	62	rxrpc_seq_t *_top,
a5af7e1f DH	63	u8 reason)
8d94aa38	64	{
f3639df2	65	rxrpc_serial_t serial;
248f219c DH	66	rxrpc_seq_t hard_ack, top, seq;
248f219c DH	67	int ix;
8d94aa38 DH	68	u32 mtu, jmax;
	69	u8 *ackp = pkt->acks;
	70
248f219c	71	/* Barrier against rxrpc_input_data(). */
f3639df2	72	serial = call->ackr_serial;
248f219c DH	73	hard_ack = READ_ONCE(call->rx_hard_ack);
248f219c DH	74	top = smp_load_acquire(&call->rx_top);
805b21b9 DH	75	*_hard_ack = hard_ack;
805b21b9 DH	76	*_top = top;
248f219c	77
8d94aa38	78	pkt->ack.bufferSpace = htons(8);
248f219c DH	79	pkt->ack.maxSkew = htons(call->ackr_skew);
248f219c DH	80	pkt->ack.firstPacket = htonl(hard_ack + 1);
8d94aa38	81	pkt->ack.previousPacket = htonl(call->ackr_prev_seq);
f3639df2	82	pkt->ack.serial = htonl(serial);
a5af7e1f	83	pkt->ack.reason = reason;
248f219c DH	84	pkt->ack.nAcks = top - hard_ack;
248f219c DH	85
a5af7e1f	86	if (reason == RXRPC_ACK_PING)
8e83134d DH	87	pkt->whdr.flags \|= RXRPC_REQUEST_ACK;
8e83134d DH	88
248f219c DH	89	if (after(top, hard_ack)) {
	90	seq = hard_ack + 1;
	91	do {
	92	ix = seq & RXRPC_RXTX_BUFF_MASK;
	93	if (call->rxtx_buffer[ix])
	94	*ackp++ = RXRPC_ACK_TYPE_ACK;
	95	else
	96	*ackp++ = RXRPC_ACK_TYPE_NACK;
	97	seq++;
	98	} while (before_eq(seq, top));
	99	}
8d94aa38	100
1457cc4c DH	101	mtu = conn->params.peer->if_mtu;
1457cc4c DH	102	mtu -= conn->params.peer->hdrsize;
75e42126	103	jmax = (call->nr_jumbo_bad > 3) ? 1 : rxrpc_rx_jumbo_max;
8d94aa38 DH	104	pkt->ackinfo.rxMTU = htonl(rxrpc_rx_mtu);
8d94aa38 DH	105	pkt->ackinfo.maxMTU = htonl(mtu);
75e42126	106	pkt->ackinfo.rwind = htonl(call->rx_winsize);
8d94aa38 DH	107	pkt->ackinfo.jumbo_max = htonl(jmax);
	108
	109	*ackp++ = 0;
	110	*ackp++ = 0;
	111	*ackp++ = 0;
248f219c	112	return top - hard_ack + 3;
8d94aa38 DH	113	}
	114
	115	/*
26cb02aa	116	* Send an ACK call packet.
8d94aa38	117	*/
bd1fdf8c DH	118	int rxrpc_send_ack_packet(struct rxrpc_call *call, bool ping,
bd1fdf8c DH	119	rxrpc_serial_t *_serial)
8d94aa38 DH	120	{
8d94aa38 DH	121	struct rxrpc_connection *conn = NULL;
26cb02aa	122	struct rxrpc_ack_buffer *pkt;
8d94aa38 DH	123	struct msghdr msg;
	124	struct kvec iov[2];
	125	rxrpc_serial_t serial;
805b21b9	126	rxrpc_seq_t hard_ack, top;
ace45bec	127	ktime_t now;
8d94aa38	128	size_t len, n;
26cb02aa	129	int ret;
a5af7e1f	130	u8 reason;
8d94aa38 DH	131
	132	spin_lock_bh(&call->lock);
	133	if (call->conn)
	134	conn = rxrpc_get_connection_maybe(call->conn);
	135	spin_unlock_bh(&call->lock);
	136	if (!conn)
	137	return -ECONNRESET;
	138
	139	pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
	140	if (!pkt) {
	141	rxrpc_put_connection(conn);
	142	return -ENOMEM;
	143	}
	144
8d94aa38 DH	145	msg.msg_name = &call->peer->srx.transport;
	146	msg.msg_namelen = call->peer->srx.transport_len;
	147	msg.msg_control = NULL;
	148	msg.msg_controllen = 0;
	149	msg.msg_flags = 0;
	150
	151	pkt->whdr.epoch = htonl(conn->proto.epoch);
	152	pkt->whdr.cid = htonl(call->cid);
	153	pkt->whdr.callNumber = htonl(call->call_id);
	154	pkt->whdr.seq = 0;
26cb02aa DH	155	pkt->whdr.type = RXRPC_PACKET_TYPE_ACK;
26cb02aa DH	156	pkt->whdr.flags = RXRPC_SLOW_START_OK \| conn->out_clientflag;
8d94aa38 DH	157	pkt->whdr.userStatus = 0;
	158	pkt->whdr.securityIndex = call->security_ix;
	159	pkt->whdr._rsvd = 0;
	160	pkt->whdr.serviceId = htons(call->service_id);
	161
26cb02aa	162	spin_lock_bh(&call->lock);
a5af7e1f DH	163	if (ping) {
	164	reason = RXRPC_ACK_PING;
	165	} else {
	166	reason = call->ackr_reason;
	167	if (!call->ackr_reason) {
	168	spin_unlock_bh(&call->lock);
	169	ret = 0;
	170	goto out;
	171	}
	172	call->ackr_reason = 0;
8d94aa38	173	}
1457cc4c	174	n = rxrpc_fill_out_ack(conn, call, pkt, &hard_ack, &top, reason);
26cb02aa DH	175
	176	spin_unlock_bh(&call->lock);
	177
	178	iov[0].iov_base = pkt;
	179	iov[0].iov_len = sizeof(pkt->whdr) + sizeof(pkt->ack) + n;
	180	iov[1].iov_base = &pkt->ackinfo;
	181	iov[1].iov_len = sizeof(pkt->ackinfo);
	182	len = iov[0].iov_len + iov[1].iov_len;
8d94aa38	183
b86e218e DH	184	serial = atomic_inc_return(&conn->serial);
b86e218e DH	185	pkt->whdr.serial = htonl(serial);
4764c0da	186	trace_rxrpc_tx_ack(call->debug_id, serial,
26cb02aa DH	187	ntohl(pkt->ack.firstPacket),
	188	ntohl(pkt->ack.serial),
	189	pkt->ack.reason, pkt->ack.nAcks);
bd1fdf8c DH	190	if (_serial)
bd1fdf8c DH	191	*_serial = serial;
b86e218e	192
8e83134d	193	if (ping) {
a5af7e1f	194	call->ping_serial = serial;
8e83134d DH	195	smp_wmb();
	196	/* We need to stick a time in before we send the packet in case
	197	* the reply gets back before kernel_sendmsg() completes - but
	198	* asking UDP to send the packet can take a relatively long
	199	* time, so we update the time after, on the assumption that
	200	* the packet transmission is more likely to happen towards the
	201	* end of the kernel_sendmsg() call.
	202	*/
a5af7e1f	203	call->ping_time = ktime_get_real();
8e83134d DH	204	set_bit(RXRPC_CALL_PINGING, &call->flags);
	205	trace_rxrpc_rtt_tx(call, rxrpc_rtt_tx_ping, serial);
	206	}
26cb02aa DH	207
26cb02aa DH	208	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
ace45bec	209	now = ktime_get_real();
8e83134d	210	if (ping)
ace45bec	211	call->ping_time = now;
330bdcfa	212	conn->params.peer->last_tx_at = ktime_get_seconds();
6b47fe1d DH	213	if (ret < 0)
6b47fe1d DH	214	trace_rxrpc_tx_fail(call->debug_id, serial, ret,
4764c0da DH	215	rxrpc_tx_point_call_ack);
	216	else
	217	trace_rxrpc_tx_packet(call->debug_id, &pkt->whdr,
	218	rxrpc_tx_point_call_ack);
8d94aa38	219
26cb02aa	220	if (call->state < RXRPC_CALL_COMPLETE) {
805b21b9	221	if (ret < 0) {
a5af7e1f DH	222	if (ping)
a5af7e1f DH	223	clear_bit(RXRPC_CALL_PINGING, &call->flags);
248f219c DH	224	rxrpc_propose_ACK(call, pkt->ack.reason,
	225	ntohs(pkt->ack.maxSkew),
	226	ntohl(pkt->ack.serial),
9c7ad434 DH	227	true, true,
9c7ad434 DH	228	rxrpc_propose_ack_retry_tx);
805b21b9 DH	229	} else {
	230	spin_lock_bh(&call->lock);
	231	if (after(hard_ack, call->ackr_consumed))
	232	call->ackr_consumed = hard_ack;
	233	if (after(top, call->ackr_seen))
	234	call->ackr_seen = top;
	235	spin_unlock_bh(&call->lock);
248f219c	236	}
415f44e4 DH	237
415f44e4 DH	238	rxrpc_set_keepalive(call);
248f219c DH	239	}
248f219c DH	240
8d94aa38 DH	241	out:
	242	rxrpc_put_connection(conn);
	243	kfree(pkt);
	244	return ret;
	245	}
	246
26cb02aa DH	247	/*
	248	* Send an ABORT call packet.
	249	*/
	250	int rxrpc_send_abort_packet(struct rxrpc_call *call)
	251	{
	252	struct rxrpc_connection *conn = NULL;
	253	struct rxrpc_abort_buffer pkt;
	254	struct msghdr msg;
	255	struct kvec iov[1];
	256	rxrpc_serial_t serial;
	257	int ret;
	258
dcbefc30 DH	259	/* Don't bother sending aborts for a client call once the server has
	260	* hard-ACK'd all of its request data. After that point, we're not
	261	* going to stop the operation proceeding, and whilst we might limit
	262	* the reply, it's not worth it if we can send a new call on the same
	263	* channel instead, thereby closing off this call.
	264	*/
	265	if (rxrpc_is_client_call(call) &&
	266	test_bit(RXRPC_CALL_TX_LAST, &call->flags))
	267	return 0;
	268
26cb02aa DH	269	spin_lock_bh(&call->lock);
	270	if (call->conn)
	271	conn = rxrpc_get_connection_maybe(call->conn);
	272	spin_unlock_bh(&call->lock);
	273	if (!conn)
	274	return -ECONNRESET;
	275
	276	msg.msg_name = &call->peer->srx.transport;
	277	msg.msg_namelen = call->peer->srx.transport_len;
	278	msg.msg_control = NULL;
	279	msg.msg_controllen = 0;
	280	msg.msg_flags = 0;
	281
	282	pkt.whdr.epoch = htonl(conn->proto.epoch);
	283	pkt.whdr.cid = htonl(call->cid);
	284	pkt.whdr.callNumber = htonl(call->call_id);
	285	pkt.whdr.seq = 0;
	286	pkt.whdr.type = RXRPC_PACKET_TYPE_ABORT;
	287	pkt.whdr.flags = conn->out_clientflag;
	288	pkt.whdr.userStatus = 0;
	289	pkt.whdr.securityIndex = call->security_ix;
	290	pkt.whdr._rsvd = 0;
	291	pkt.whdr.serviceId = htons(call->service_id);
	292	pkt.abort_code = htonl(call->abort_code);
	293
	294	iov[0].iov_base = &pkt;
	295	iov[0].iov_len = sizeof(pkt);
	296
	297	serial = atomic_inc_return(&conn->serial);
	298	pkt.whdr.serial = htonl(serial);
	299
	300	ret = kernel_sendmsg(conn->params.local->socket,
	301	&msg, iov, 1, sizeof(pkt));
330bdcfa	302	conn->params.peer->last_tx_at = ktime_get_seconds();
6b47fe1d DH	303	if (ret < 0)
6b47fe1d DH	304	trace_rxrpc_tx_fail(call->debug_id, serial, ret,
4764c0da DH	305	rxrpc_tx_point_call_abort);
	306	else
	307	trace_rxrpc_tx_packet(call->debug_id, &pkt.whdr,
	308	rxrpc_tx_point_call_abort);
6b47fe1d	309
26cb02aa DH	310
	311	rxrpc_put_connection(conn);
	312	return ret;
	313	}
	314
17926a79 DH	315	/*
	316	* send a packet through the transport endpoint
	317	*/
a1767077 DH	318	int rxrpc_send_data_packet(struct rxrpc_call call, struct sk_buff skb,
a1767077 DH	319	bool retrans)
17926a79	320	{
5a924b89 DH	321	struct rxrpc_connection *conn = call->conn;
	322	struct rxrpc_wire_header whdr;
	323	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
17926a79	324	struct msghdr msg;
5a924b89 DH	325	struct kvec iov[2];
	326	rxrpc_serial_t serial;
	327	size_t len;
a1767077	328	bool lost = false;
17926a79 DH	329	int ret, opt;
	330
	331	_enter(",{%d}", skb->len);
	332
5a924b89 DH	333	/* Each transmission of a Tx packet needs a new serial number */
5a924b89 DH	334	serial = atomic_inc_return(&conn->serial);
17926a79	335
5a924b89 DH	336	whdr.epoch = htonl(conn->proto.epoch);
	337	whdr.cid = htonl(call->cid);
	338	whdr.callNumber = htonl(call->call_id);
	339	whdr.seq = htonl(sp->hdr.seq);
	340	whdr.serial = htonl(serial);
	341	whdr.type = RXRPC_PACKET_TYPE_DATA;
	342	whdr.flags = sp->hdr.flags;
	343	whdr.userStatus = 0;
	344	whdr.securityIndex = call->security_ix;
	345	whdr._rsvd = htons(sp->hdr._rsvd);
	346	whdr.serviceId = htons(call->service_id);
	347
4e255721 DH	348	if (test_bit(RXRPC_CONN_PROBING_FOR_UPGRADE, &conn->flags) &&
	349	sp->hdr.seq == 1)
	350	whdr.userStatus = RXRPC_USERSTATUS_SERVICE_UPGRADE;
	351
5a924b89 DH	352	iov[0].iov_base = &whdr;
	353	iov[0].iov_len = sizeof(whdr);
	354	iov[1].iov_base = skb->head;
	355	iov[1].iov_len = skb->len;
	356	len = iov[0].iov_len + iov[1].iov_len;
	357
	358	msg.msg_name = &call->peer->srx.transport;
	359	msg.msg_namelen = call->peer->srx.transport_len;
17926a79 DH	360	msg.msg_control = NULL;
	361	msg.msg_controllen = 0;
	362	msg.msg_flags = 0;
	363
57494343 DH	364	/* If our RTT cache needs working on, request an ACK. Also request
	365	* ACKs if a DATA packet appears to have been lost.
	366	*/
bf7d620a	367	if (!(sp->hdr.flags & RXRPC_LAST_PACKET) &&
bd1fdf8c DH	368	(test_and_clear_bit(RXRPC_CALL_EV_ACK_LOST, &call->events) \|\|
bd1fdf8c DH	369	retrans \|\|
bf7d620a DH	370	call->cong_mode == RXRPC_CALL_SLOW_START \|\|
	371	(call->peer->rtt_usage < 3 && sp->hdr.seq & 1) \|\|
	372	ktime_before(ktime_add_ms(call->peer->rtt_last_req, 1000),
	373	ktime_get_real())))
0d4b103c DH	374	whdr.flags \|= RXRPC_REQUEST_ACK;
0d4b103c DH	375
8a681c36 DH	376	if (IS_ENABLED(CONFIG_AF_RXRPC_INJECT_LOSS)) {
	377	static int lose;
	378	if ((lose++ & 7) == 7) {
a1767077 DH	379	ret = 0;
	380	lost = true;
	381	goto done;
8a681c36 DH	382	}
	383	}
	384
5a924b89 DH	385	_proto("Tx DATA %%%u { #%u }", serial, sp->hdr.seq);
5a924b89 DH	386
17926a79 DH	387	/* send the packet with the don't fragment bit set if we currently
17926a79 DH	388	* think it's small enough */
5a924b89 DH	389	if (iov[1].iov_len >= call->peer->maxdata)
	390	goto send_fragmentable;
	391
	392	down_read(&conn->params.local->defrag_sem);
	393	/* send the packet by UDP
	394	* - returns -EMSGSIZE if UDP would have to fragment the packet
	395	* to go out of the interface
	396	* - in which case, we'll have processed the ICMP error
	397	* message and update the peer record
	398	*/
	399	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
330bdcfa	400	conn->params.peer->last_tx_at = ktime_get_seconds();
5a924b89 DH	401
5a924b89 DH	402	up_read(&conn->params.local->defrag_sem);
6b47fe1d DH	403	if (ret < 0)
6b47fe1d DH	404	trace_rxrpc_tx_fail(call->debug_id, serial, ret,
4764c0da DH	405	rxrpc_tx_point_call_data_nofrag);
	406	else
	407	trace_rxrpc_tx_packet(call->debug_id, &whdr,
	408	rxrpc_tx_point_call_data_nofrag);
5a924b89 DH	409	if (ret == -EMSGSIZE)
	410	goto send_fragmentable;
	411
	412	done:
a1767077 DH	413	trace_rxrpc_tx_data(call, sp->hdr.seq, serial, whdr.flags,
a1767077 DH	414	retrans, lost);
50235c4b	415	if (ret >= 0) {
0d4b103c DH	416	ktime_t now = ktime_get_real();
0d4b103c DH	417	skb->tstamp = now;
50235c4b	418	smp_wmb();
5a924b89	419	sp->hdr.serial = serial;
0d4b103c DH	420	if (whdr.flags & RXRPC_REQUEST_ACK) {
0d4b103c DH	421	call->peer->rtt_last_req = now;
50235c4b	422	trace_rxrpc_rtt_tx(call, rxrpc_rtt_tx_data, serial);
bd1fdf8c DH	423	if (call->peer->rtt_usage > 1) {
	424	unsigned long nowj = jiffies, ack_lost_at;
	425
	426	ack_lost_at = nsecs_to_jiffies(2 * call->peer->rtt);
	427	if (ack_lost_at < 1)
	428	ack_lost_at = 1;
	429
	430	ack_lost_at += nowj;
	431	WRITE_ONCE(call->ack_lost_at, ack_lost_at);
	432	rxrpc_reduce_call_timer(call, ack_lost_at, nowj,
	433	rxrpc_timer_set_for_lost_ack);
	434	}
0d4b103c	435	}
c54e43d7 DH	436
	437	if (sp->hdr.seq == 1 &&
	438	!test_and_set_bit(RXRPC_CALL_BEGAN_RX_TIMER,
	439	&call->flags)) {
	440	unsigned long nowj = jiffies, expect_rx_by;
	441
	442	expect_rx_by = nowj + call->next_rx_timo;
	443	WRITE_ONCE(call->expect_rx_by, expect_rx_by);
	444	rxrpc_reduce_call_timer(call, expect_rx_by, nowj,
	445	rxrpc_timer_set_for_normal);
	446	}
17926a79	447	}
415f44e4 DH	448
	449	rxrpc_set_keepalive(call);
	450
5a924b89 DH	451	_leave(" = %d [%u]", ret, call->peer->maxdata);
5a924b89 DH	452	return ret;
17926a79 DH	453
	454	send_fragmentable:
	455	/* attempt to send this message with fragmentation enabled */
	456	_debug("send fragment");
	457
985a5c82 DH	458	down_write(&conn->params.local->defrag_sem);
	459
	460	switch (conn->params.local->srx.transport.family) {
	461	case AF_INET:
	462	opt = IP_PMTUDISC_DONT;
	463	ret = kernel_setsockopt(conn->params.local->socket,
	464	SOL_IP, IP_MTU_DISCOVER,
	465	(char *)&opt, sizeof(opt));
	466	if (ret == 0) {
5a924b89 DH	467	ret = kernel_sendmsg(conn->params.local->socket, &msg,
5a924b89 DH	468	iov, 2, len);
330bdcfa	469	conn->params.peer->last_tx_at = ktime_get_seconds();
985a5c82 DH	470
	471	opt = IP_PMTUDISC_DO;
	472	kernel_setsockopt(conn->params.local->socket, SOL_IP,
	473	IP_MTU_DISCOVER,
	474	(char *)&opt, sizeof(opt));
	475	}
	476	break;
75b54cb5	477
d1912747	478	#ifdef CONFIG_AF_RXRPC_IPV6
75b54cb5 DH	479	case AF_INET6:
	480	opt = IPV6_PMTUDISC_DONT;
	481	ret = kernel_setsockopt(conn->params.local->socket,
	482	SOL_IPV6, IPV6_MTU_DISCOVER,
	483	(char *)&opt, sizeof(opt));
	484	if (ret == 0) {
	485	ret = kernel_sendmsg(conn->params.local->socket, &msg,
93c62c45	486	iov, 2, len);
330bdcfa	487	conn->params.peer->last_tx_at = ktime_get_seconds();
75b54cb5 DH	488
	489	opt = IPV6_PMTUDISC_DO;
	490	kernel_setsockopt(conn->params.local->socket,
	491	SOL_IPV6, IPV6_MTU_DISCOVER,
	492	(char *)&opt, sizeof(opt));
	493	}
	494	break;
d1912747	495	#endif
17926a79 DH	496	}
17926a79 DH	497
6b47fe1d DH	498	if (ret < 0)
6b47fe1d DH	499	trace_rxrpc_tx_fail(call->debug_id, serial, ret,
4764c0da DH	500	rxrpc_tx_point_call_data_frag);
	501	else
	502	trace_rxrpc_tx_packet(call->debug_id, &whdr,
	503	rxrpc_tx_point_call_data_frag);
6b47fe1d	504
985a5c82	505	up_write(&conn->params.local->defrag_sem);
5a924b89	506	goto done;
17926a79	507	}
248f219c DH	508
	509	/*
	510	* reject packets through the local endpoint
	511	*/
	512	void rxrpc_reject_packets(struct rxrpc_local *local)
	513	{
1c2bc7b9	514	struct sockaddr_rxrpc srx;
248f219c DH	515	struct rxrpc_skb_priv *sp;
	516	struct rxrpc_wire_header whdr;
	517	struct sk_buff *skb;
	518	struct msghdr msg;
	519	struct kvec iov[2];
	520	size_t size;
	521	__be32 code;
6b47fe1d	522	int ret;
248f219c DH	523
	524	_enter("%d", local->debug_id);
	525
	526	iov[0].iov_base = &whdr;
	527	iov[0].iov_len = sizeof(whdr);
	528	iov[1].iov_base = &code;
	529	iov[1].iov_len = sizeof(code);
	530	size = sizeof(whdr) + sizeof(code);
	531
1c2bc7b9	532	msg.msg_name = &srx.transport;
248f219c DH	533	msg.msg_control = NULL;
	534	msg.msg_controllen = 0;
	535	msg.msg_flags = 0;
	536
248f219c DH	537	memset(&whdr, 0, sizeof(whdr));
	538	whdr.type = RXRPC_PACKET_TYPE_ABORT;
	539
	540	while ((skb = skb_dequeue(&local->reject_queue))) {
71f3ca40	541	rxrpc_see_skb(skb, rxrpc_skb_rx_seen);
248f219c	542	sp = rxrpc_skb(skb);
1c2bc7b9	543
7b674e39	544	if (rxrpc_extract_addr_from_skb(local, &srx, skb) == 0) {
1c2bc7b9 DH	545	msg.msg_namelen = srx.transport_len;
1c2bc7b9 DH	546
248f219c DH	547	code = htonl(skb->priority);
	548
	549	whdr.epoch = htonl(sp->hdr.epoch);
	550	whdr.cid = htonl(sp->hdr.cid);
	551	whdr.callNumber = htonl(sp->hdr.callNumber);
	552	whdr.serviceId = htons(sp->hdr.serviceId);
	553	whdr.flags = sp->hdr.flags;
	554	whdr.flags ^= RXRPC_CLIENT_INITIATED;
	555	whdr.flags &= RXRPC_CLIENT_INITIATED;
	556
6b47fe1d DH	557	ret = kernel_sendmsg(local->socket, &msg, iov, 2, size);
	558	if (ret < 0)
	559	trace_rxrpc_tx_fail(local->debug_id, 0, ret,
4764c0da DH	560	rxrpc_tx_point_reject);
	561	else
	562	trace_rxrpc_tx_packet(local->debug_id, &whdr,
	563	rxrpc_tx_point_reject);
248f219c DH	564	}
248f219c DH	565
71f3ca40	566	rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
248f219c DH	567	}
	568
	569	_leave("");
	570	}
ace45bec DH	571
	572	/*
	573	* Send a VERSION reply to a peer as a keepalive.
	574	*/
	575	void rxrpc_send_keepalive(struct rxrpc_peer *peer)
	576	{
	577	struct rxrpc_wire_header whdr;
	578	struct msghdr msg;
	579	struct kvec iov[2];
	580	size_t len;
	581	int ret;
	582
	583	_enter("");
	584
	585	msg.msg_name = &peer->srx.transport;
	586	msg.msg_namelen = peer->srx.transport_len;
	587	msg.msg_control = NULL;
	588	msg.msg_controllen = 0;
	589	msg.msg_flags = 0;
	590
	591	whdr.epoch = htonl(peer->local->rxnet->epoch);
	592	whdr.cid = 0;
	593	whdr.callNumber = 0;
	594	whdr.seq = 0;
	595	whdr.serial = 0;
	596	whdr.type = RXRPC_PACKET_TYPE_VERSION; /* Not client-initiated */
	597	whdr.flags = RXRPC_LAST_PACKET;
	598	whdr.userStatus = 0;
	599	whdr.securityIndex = 0;
	600	whdr._rsvd = 0;
	601	whdr.serviceId = 0;
	602
	603	iov[0].iov_base = &whdr;
	604	iov[0].iov_len = sizeof(whdr);
	605	iov[1].iov_base = (char *)rxrpc_keepalive_string;
	606	iov[1].iov_len = sizeof(rxrpc_keepalive_string);
	607
	608	len = iov[0].iov_len + iov[1].iov_len;
	609
	610	_proto("Tx VERSION (keepalive)");
	611
	612	ret = kernel_sendmsg(peer->local->socket, &msg, iov, 2, len);
	613	if (ret < 0)
6b47fe1d	614	trace_rxrpc_tx_fail(peer->debug_id, 0, ret,
4764c0da DH	615	rxrpc_tx_point_version_keepalive);
	616	else
	617	trace_rxrpc_tx_packet(peer->debug_id, &whdr,
	618	rxrpc_tx_point_version_keepalive);
ace45bec	619
330bdcfa	620	peer->last_tx_at = ktime_get_seconds();
ace45bec DH	621	_leave("");
ace45bec DH	622	}