[thirdparty/linux.git] / net / rxrpc / output.c

// SPDX-License-Identifier: GPL-2.0-or-later
/* RxRPC packet transmission
 *
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 */

#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[] = "";

/*
 * Increase Tx backoff on transmission failure and clear it on success.
 */
static void rxrpc_tx_backoff(struct rxrpc_call *call, int ret)
{
	if (ret < 0) {
		u16 tx_backoff = READ_ONCE(call->tx_backoff);

		if (tx_backoff < HZ)
			WRITE_ONCE(call->tx_backoff, tx_backoff + 1);
	} else {
		WRITE_ONCE(call->tx_backoff, 0);
	}
}

/*
 * 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(0);
	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;
	struct rxrpc_ack_buffer *pkt;
	struct msghdr msg;
	struct kvec iov[2];
	rxrpc_serial_t serial;
	rxrpc_seq_t hard_ack, top;
	size_t len, n;
	int ret;
	u8 reason;

	if (test_bit(RXRPC_CALL_DISCONNECTED, &call->flags))
		return -ECONNRESET;

	pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
	if (!pkt)
		return -ENOMEM;

	conn = call->conn;

	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.
		 */
		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);
	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);
	rxrpc_tx_backoff(call, ret);

	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,
					  ntohl(pkt->ack.serial),
					  false, 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:
	kfree(pkt);
	return ret;
}

/*
 * Send an ABORT call packet.
 */
int rxrpc_send_abort_packet(struct rxrpc_call *call)
{
	struct rxrpc_connection *conn;
	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;

	if (test_bit(RXRPC_CALL_DISCONNECTED, &call->flags))
		return -ECONNRESET;

	conn = call->conn;

	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_tx_backoff(call, ret);
	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;
	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.
	 *
	 * However, we mustn't request an ACK on the last reply packet of a
	 * service call, lest OpenAFS incorrectly send us an ACK with some
	 * soft-ACKs in it and then never follow up with a proper hard ACK.
	 */
	if ((!(sp->hdr.flags & RXRPC_LAST_PACKET) ||
	     rxrpc_to_server(sp)
	     ) &&
	    (test_and_clear_bit(RXRPC_CALL_EV_ACK_LOST, &call->events) ||
	     retrans ||
	     call->cong_mode == RXRPC_CALL_SLOW_START ||
	     (call->peer->rtt_count < 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;
			trace_rxrpc_tx_data(call, sp->hdr.seq, serial,
					    whdr.flags, retrans, true);
			goto done;
		}
	}

	trace_rxrpc_tx_data(call, sp->hdr.seq, serial, whdr.flags, retrans,
			    false);

	/* 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);

	sp->hdr.serial = serial;
	smp_wmb(); /* Set serial before timestamp */
	skb->tstamp = ktime_get_real();

	/* 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);
	rxrpc_tx_backoff(call, ret);
	if (ret == -EMSGSIZE)
		goto send_fragmentable;

done:
	if (ret >= 0) {
		if (whdr.flags & RXRPC_REQUEST_ACK) {
			call->peer->rtt_last_req = skb->tstamp;
			trace_rxrpc_rtt_tx(call, rxrpc_rtt_tx_data, serial);
			if (call->peer->rtt_count > 1) {
				unsigned long nowj = jiffies, ack_lost_at;

				ack_lost_at = rxrpc_get_rto_backoff(call->peer, retrans);
				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);
	} else {
		/* Cancel the call if the initial transmission fails,
		 * particularly if that's due to network routing issues that
		 * aren't going away anytime soon.  The layer above can arrange
		 * the retransmission.
		 */
		if (!test_and_set_bit(RXRPC_CALL_BEGAN_RX_TIMER, &call->flags))
			rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
						  RX_USER_ABORT, ret);
	}

	_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);

	sp->hdr.serial = serial;
	smp_wmb(); /* Set serial before timestamp */
	skb->tstamp = ktime_get_real();

	switch (conn->params.local->srx.transport.family) {
	case AF_INET6:
	case AF_INET:
		opt = IP_PMTUDISC_DONT;
		kernel_setsockopt(conn->params.local->socket,
				  SOL_IP, IP_MTU_DISCOVER,
				  (char *)&opt, sizeof(opt));
		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;

	default:
		BUG();
	}

	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);
	rxrpc_tx_backoff(call, ret);

	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, ioc;

	_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);

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

	memset(&whdr, 0, sizeof(whdr));

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

		switch (skb->mark) {
		case RXRPC_SKB_MARK_REJECT_BUSY:
			whdr.type = RXRPC_PACKET_TYPE_BUSY;
			size = sizeof(whdr);
			ioc = 1;
			break;
		case RXRPC_SKB_MARK_REJECT_ABORT:
			whdr.type = RXRPC_PACKET_TYPE_ABORT;
			code = htonl(skb->priority);
			size = sizeof(whdr) + sizeof(code);
			ioc = 2;
			break;
		default:
			rxrpc_free_skb(skb, rxrpc_skb_freed);
			continue;
		}

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

			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, ioc, 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_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
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
17926a79 DH	2	/* RxRPC packet transmission
	3	*
	4	* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
	5	* Written by David Howells (dhowells@redhat.com)
17926a79 DH	6	*/
17926a79 DH	7
9b6d5398 JP	8	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9b6d5398 JP	9
17926a79	10	#include <linux/net.h>
5a0e3ad6	11	#include <linux/gfp.h>
17926a79	12	#include <linux/skbuff.h>
bc3b2d7f	13	#include <linux/export.h>
17926a79 DH	14	#include <net/sock.h>
	15	#include <net/af_rxrpc.h>
	16	#include "ar-internal.h"
	17
26cb02aa	18	struct rxrpc_ack_buffer {
8d94aa38	19	struct rxrpc_wire_header whdr;
26cb02aa DH	20	struct rxrpc_ackpacket ack;
	21	u8 acks[255];
	22	u8 pad[3];
8d94aa38 DH	23	struct rxrpc_ackinfo ackinfo;
	24	};
	25
26cb02aa DH	26	struct rxrpc_abort_buffer {
	27	struct rxrpc_wire_header whdr;
	28	__be32 abort_code;
	29	};
	30
ace45bec DH	31	static const char rxrpc_keepalive_string[] = "";
ace45bec DH	32
c7e86acf DH	33	/*
	34	* Increase Tx backoff on transmission failure and clear it on success.
	35	*/
	36	static void rxrpc_tx_backoff(struct rxrpc_call *call, int ret)
	37	{
	38	if (ret < 0) {
	39	u16 tx_backoff = READ_ONCE(call->tx_backoff);
	40
	41	if (tx_backoff < HZ)
	42	WRITE_ONCE(call->tx_backoff, tx_backoff + 1);
	43	} else {
	44	WRITE_ONCE(call->tx_backoff, 0);
	45	}
	46	}
	47
415f44e4 DH	48	/*
	49	* Arrange for a keepalive ping a certain time after we last transmitted. This
	50	* lets the far side know we're still interested in this call and helps keep
	51	* the route through any intervening firewall open.
	52	*
	53	* Receiving a response to the ping will prevent the ->expect_rx_by timer from
	54	* expiring.
	55	*/
	56	static void rxrpc_set_keepalive(struct rxrpc_call *call)
	57	{
	58	unsigned long now = jiffies, keepalive_at = call->next_rx_timo / 6;
	59
	60	keepalive_at += now;
	61	WRITE_ONCE(call->keepalive_at, keepalive_at);
	62	rxrpc_reduce_call_timer(call, keepalive_at, now,
	63	rxrpc_timer_set_for_keepalive);
	64	}
	65
8d94aa38 DH	66	/*
	67	* Fill out an ACK packet.
	68	*/
1457cc4c DH	69	static size_t rxrpc_fill_out_ack(struct rxrpc_connection *conn,
1457cc4c DH	70	struct rxrpc_call *call,
26cb02aa	71	struct rxrpc_ack_buffer *pkt,
805b21b9	72	rxrpc_seq_t *_hard_ack,
a5af7e1f DH	73	rxrpc_seq_t *_top,
a5af7e1f DH	74	u8 reason)
8d94aa38	75	{
f3639df2	76	rxrpc_serial_t serial;
248f219c DH	77	rxrpc_seq_t hard_ack, top, seq;
248f219c DH	78	int ix;
8d94aa38 DH	79	u32 mtu, jmax;
	80	u8 *ackp = pkt->acks;
	81
248f219c	82	/* Barrier against rxrpc_input_data(). */
f3639df2	83	serial = call->ackr_serial;
248f219c DH	84	hard_ack = READ_ONCE(call->rx_hard_ack);
248f219c DH	85	top = smp_load_acquire(&call->rx_top);
805b21b9 DH	86	*_hard_ack = hard_ack;
805b21b9 DH	87	*_top = top;
248f219c	88
8d94aa38	89	pkt->ack.bufferSpace = htons(8);
e8c3af6b	90	pkt->ack.maxSkew = htons(0);
248f219c	91	pkt->ack.firstPacket = htonl(hard_ack + 1);
8d94aa38	92	pkt->ack.previousPacket = htonl(call->ackr_prev_seq);
f3639df2	93	pkt->ack.serial = htonl(serial);
a5af7e1f	94	pkt->ack.reason = reason;
248f219c DH	95	pkt->ack.nAcks = top - hard_ack;
248f219c DH	96
a5af7e1f	97	if (reason == RXRPC_ACK_PING)
8e83134d DH	98	pkt->whdr.flags \|= RXRPC_REQUEST_ACK;
8e83134d DH	99
248f219c DH	100	if (after(top, hard_ack)) {
	101	seq = hard_ack + 1;
	102	do {
	103	ix = seq & RXRPC_RXTX_BUFF_MASK;
	104	if (call->rxtx_buffer[ix])
	105	*ackp++ = RXRPC_ACK_TYPE_ACK;
	106	else
	107	*ackp++ = RXRPC_ACK_TYPE_NACK;
	108	seq++;
	109	} while (before_eq(seq, top));
	110	}
8d94aa38	111
1457cc4c DH	112	mtu = conn->params.peer->if_mtu;
1457cc4c DH	113	mtu -= conn->params.peer->hdrsize;
75e42126	114	jmax = (call->nr_jumbo_bad > 3) ? 1 : rxrpc_rx_jumbo_max;
8d94aa38 DH	115	pkt->ackinfo.rxMTU = htonl(rxrpc_rx_mtu);
8d94aa38 DH	116	pkt->ackinfo.maxMTU = htonl(mtu);
75e42126	117	pkt->ackinfo.rwind = htonl(call->rx_winsize);
8d94aa38 DH	118	pkt->ackinfo.jumbo_max = htonl(jmax);
	119
	120	*ackp++ = 0;
	121	*ackp++ = 0;
	122	*ackp++ = 0;
248f219c	123	return top - hard_ack + 3;
8d94aa38 DH	124	}
	125
	126	/*
26cb02aa	127	* Send an ACK call packet.
8d94aa38	128	*/
bd1fdf8c DH	129	int rxrpc_send_ack_packet(struct rxrpc_call *call, bool ping,
bd1fdf8c DH	130	rxrpc_serial_t *_serial)
8d94aa38	131	{
5273a191	132	struct rxrpc_connection *conn;
26cb02aa	133	struct rxrpc_ack_buffer *pkt;
8d94aa38 DH	134	struct msghdr msg;
	135	struct kvec iov[2];
	136	rxrpc_serial_t serial;
805b21b9	137	rxrpc_seq_t hard_ack, top;
8d94aa38	138	size_t len, n;
26cb02aa	139	int ret;
a5af7e1f	140	u8 reason;
8d94aa38	141
5273a191	142	if (test_bit(RXRPC_CALL_DISCONNECTED, &call->flags))
8d94aa38 DH	143	return -ECONNRESET;
	144
	145	pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
5273a191	146	if (!pkt)
8d94aa38	147	return -ENOMEM;
5273a191 DH	148
5273a191 DH	149	conn = call->conn;
8d94aa38	150
8d94aa38 DH	151	msg.msg_name = &call->peer->srx.transport;
	152	msg.msg_namelen = call->peer->srx.transport_len;
	153	msg.msg_control = NULL;
	154	msg.msg_controllen = 0;
	155	msg.msg_flags = 0;
	156
	157	pkt->whdr.epoch = htonl(conn->proto.epoch);
	158	pkt->whdr.cid = htonl(call->cid);
	159	pkt->whdr.callNumber = htonl(call->call_id);
	160	pkt->whdr.seq = 0;
26cb02aa DH	161	pkt->whdr.type = RXRPC_PACKET_TYPE_ACK;
26cb02aa DH	162	pkt->whdr.flags = RXRPC_SLOW_START_OK \| conn->out_clientflag;
8d94aa38 DH	163	pkt->whdr.userStatus = 0;
	164	pkt->whdr.securityIndex = call->security_ix;
	165	pkt->whdr._rsvd = 0;
	166	pkt->whdr.serviceId = htons(call->service_id);
	167
26cb02aa	168	spin_lock_bh(&call->lock);
a5af7e1f DH	169	if (ping) {
	170	reason = RXRPC_ACK_PING;
	171	} else {
	172	reason = call->ackr_reason;
	173	if (!call->ackr_reason) {
	174	spin_unlock_bh(&call->lock);
	175	ret = 0;
	176	goto out;
	177	}
	178	call->ackr_reason = 0;
8d94aa38	179	}
1457cc4c	180	n = rxrpc_fill_out_ack(conn, call, pkt, &hard_ack, &top, reason);
26cb02aa DH	181
	182	spin_unlock_bh(&call->lock);
	183
	184	iov[0].iov_base = pkt;
	185	iov[0].iov_len = sizeof(pkt->whdr) + sizeof(pkt->ack) + n;
	186	iov[1].iov_base = &pkt->ackinfo;
	187	iov[1].iov_len = sizeof(pkt->ackinfo);
	188	len = iov[0].iov_len + iov[1].iov_len;
8d94aa38	189
b86e218e DH	190	serial = atomic_inc_return(&conn->serial);
b86e218e DH	191	pkt->whdr.serial = htonl(serial);
4764c0da	192	trace_rxrpc_tx_ack(call->debug_id, serial,
26cb02aa DH	193	ntohl(pkt->ack.firstPacket),
	194	ntohl(pkt->ack.serial),
	195	pkt->ack.reason, pkt->ack.nAcks);
bd1fdf8c DH	196	if (_serial)
bd1fdf8c DH	197	*_serial = serial;
b86e218e	198
8e83134d	199	if (ping) {
a5af7e1f	200	call->ping_serial = serial;
8e83134d DH	201	smp_wmb();
	202	/* We need to stick a time in before we send the packet in case
	203	* the reply gets back before kernel_sendmsg() completes - but
	204	* asking UDP to send the packet can take a relatively long
b604dd98	205	* time.
8e83134d	206	*/
a5af7e1f	207	call->ping_time = ktime_get_real();
8e83134d DH	208	set_bit(RXRPC_CALL_PINGING, &call->flags);
	209	trace_rxrpc_rtt_tx(call, rxrpc_rtt_tx_ping, serial);
	210	}
26cb02aa DH	211
26cb02aa DH	212	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
330bdcfa	213	conn->params.peer->last_tx_at = ktime_get_seconds();
6b47fe1d DH	214	if (ret < 0)
6b47fe1d DH	215	trace_rxrpc_tx_fail(call->debug_id, serial, ret,
4764c0da DH	216	rxrpc_tx_point_call_ack);
	217	else
	218	trace_rxrpc_tx_packet(call->debug_id, &pkt->whdr,
	219	rxrpc_tx_point_call_ack);
c7e86acf	220	rxrpc_tx_backoff(call, ret);
8d94aa38	221
26cb02aa	222	if (call->state < RXRPC_CALL_COMPLETE) {
805b21b9	223	if (ret < 0) {
a5af7e1f DH	224	if (ping)
a5af7e1f DH	225	clear_bit(RXRPC_CALL_PINGING, &call->flags);
248f219c	226	rxrpc_propose_ACK(call, pkt->ack.reason,
248f219c	227	ntohl(pkt->ack.serial),
c7e86acf	228	false, true,
9c7ad434	229	rxrpc_propose_ack_retry_tx);
805b21b9 DH	230	} else {
	231	spin_lock_bh(&call->lock);
	232	if (after(hard_ack, call->ackr_consumed))
	233	call->ackr_consumed = hard_ack;
	234	if (after(top, call->ackr_seen))
	235	call->ackr_seen = top;
	236	spin_unlock_bh(&call->lock);
248f219c	237	}
415f44e4 DH	238
415f44e4 DH	239	rxrpc_set_keepalive(call);
248f219c DH	240	}
248f219c DH	241
8d94aa38	242	out:
8d94aa38 DH	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	{
5273a191	252	struct rxrpc_connection *conn;
26cb02aa DH	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
5273a191	269	if (test_bit(RXRPC_CALL_DISCONNECTED, &call->flags))
26cb02aa DH	270	return -ECONNRESET;
26cb02aa DH	271
5273a191 DH	272	conn = call->conn;
5273a191 DH	273
26cb02aa DH	274	msg.msg_name = &call->peer->srx.transport;
	275	msg.msg_namelen = call->peer->srx.transport_len;
	276	msg.msg_control = NULL;
	277	msg.msg_controllen = 0;
	278	msg.msg_flags = 0;
	279
	280	pkt.whdr.epoch = htonl(conn->proto.epoch);
	281	pkt.whdr.cid = htonl(call->cid);
	282	pkt.whdr.callNumber = htonl(call->call_id);
	283	pkt.whdr.seq = 0;
	284	pkt.whdr.type = RXRPC_PACKET_TYPE_ABORT;
	285	pkt.whdr.flags = conn->out_clientflag;
	286	pkt.whdr.userStatus = 0;
	287	pkt.whdr.securityIndex = call->security_ix;
	288	pkt.whdr._rsvd = 0;
	289	pkt.whdr.serviceId = htons(call->service_id);
	290	pkt.abort_code = htonl(call->abort_code);
	291
	292	iov[0].iov_base = &pkt;
	293	iov[0].iov_len = sizeof(pkt);
	294
	295	serial = atomic_inc_return(&conn->serial);
	296	pkt.whdr.serial = htonl(serial);
	297
	298	ret = kernel_sendmsg(conn->params.local->socket,
	299	&msg, iov, 1, sizeof(pkt));
330bdcfa	300	conn->params.peer->last_tx_at = ktime_get_seconds();
6b47fe1d DH	301	if (ret < 0)
6b47fe1d DH	302	trace_rxrpc_tx_fail(call->debug_id, serial, ret,
4764c0da DH	303	rxrpc_tx_point_call_abort);
	304	else
	305	trace_rxrpc_tx_packet(call->debug_id, &pkt.whdr,
	306	rxrpc_tx_point_call_abort);
c7e86acf	307	rxrpc_tx_backoff(call, ret);
26cb02aa DH	308	return ret;
	309	}
	310
17926a79 DH	311	/*
	312	* send a packet through the transport endpoint
	313	*/
a1767077 DH	314	int rxrpc_send_data_packet(struct rxrpc_call call, struct sk_buff skb,
a1767077 DH	315	bool retrans)
17926a79	316	{
5a924b89 DH	317	struct rxrpc_connection *conn = call->conn;
	318	struct rxrpc_wire_header whdr;
	319	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
17926a79	320	struct msghdr msg;
5a924b89 DH	321	struct kvec iov[2];
	322	rxrpc_serial_t serial;
	323	size_t len;
17926a79 DH	324	int ret, opt;
	325
	326	_enter(",{%d}", skb->len);
	327
5a924b89 DH	328	/* Each transmission of a Tx packet needs a new serial number */
5a924b89 DH	329	serial = atomic_inc_return(&conn->serial);
17926a79	330
5a924b89 DH	331	whdr.epoch = htonl(conn->proto.epoch);
	332	whdr.cid = htonl(call->cid);
	333	whdr.callNumber = htonl(call->call_id);
	334	whdr.seq = htonl(sp->hdr.seq);
	335	whdr.serial = htonl(serial);
	336	whdr.type = RXRPC_PACKET_TYPE_DATA;
	337	whdr.flags = sp->hdr.flags;
	338	whdr.userStatus = 0;
	339	whdr.securityIndex = call->security_ix;
	340	whdr._rsvd = htons(sp->hdr._rsvd);
	341	whdr.serviceId = htons(call->service_id);
	342
4e255721 DH	343	if (test_bit(RXRPC_CONN_PROBING_FOR_UPGRADE, &conn->flags) &&
	344	sp->hdr.seq == 1)
	345	whdr.userStatus = RXRPC_USERSTATUS_SERVICE_UPGRADE;
	346
5a924b89 DH	347	iov[0].iov_base = &whdr;
	348	iov[0].iov_len = sizeof(whdr);
	349	iov[1].iov_base = skb->head;
	350	iov[1].iov_len = skb->len;
	351	len = iov[0].iov_len + iov[1].iov_len;
	352
	353	msg.msg_name = &call->peer->srx.transport;
	354	msg.msg_namelen = call->peer->srx.transport_len;
17926a79 DH	355	msg.msg_control = NULL;
	356	msg.msg_controllen = 0;
	357	msg.msg_flags = 0;
	358
57494343 DH	359	/* If our RTT cache needs working on, request an ACK. Also request
57494343 DH	360	* ACKs if a DATA packet appears to have been lost.
b604dd98 DH	361	*
	362	* However, we mustn't request an ACK on the last reply packet of a
	363	* service call, lest OpenAFS incorrectly send us an ACK with some
	364	* soft-ACKs in it and then never follow up with a proper hard ACK.
57494343	365	*/
b604dd98 DH	366	if ((!(sp->hdr.flags & RXRPC_LAST_PACKET) \|\|
	367	rxrpc_to_server(sp)
	368	) &&
bd1fdf8c DH	369	(test_and_clear_bit(RXRPC_CALL_EV_ACK_LOST, &call->events) \|\|
bd1fdf8c DH	370	retrans \|\|
bf7d620a	371	call->cong_mode == RXRPC_CALL_SLOW_START \|\|
c410bf01	372	(call->peer->rtt_count < 3 && sp->hdr.seq & 1) \|\|
bf7d620a DH	373	ktime_before(ktime_add_ms(call->peer->rtt_last_req, 1000),
bf7d620a DH	374	ktime_get_real())))
0d4b103c DH	375	whdr.flags \|= RXRPC_REQUEST_ACK;
0d4b103c DH	376
8a681c36 DH	377	if (IS_ENABLED(CONFIG_AF_RXRPC_INJECT_LOSS)) {
	378	static int lose;
	379	if ((lose++ & 7) == 7) {
a1767077	380	ret = 0;
526949e8 AB	381	trace_rxrpc_tx_data(call, sp->hdr.seq, serial,
	382	whdr.flags, retrans, true);
	383	goto done;
8a681c36 DH	384	}
	385	}
	386
526949e8 AB	387	trace_rxrpc_tx_data(call, sp->hdr.seq, serial, whdr.flags, retrans,
526949e8 AB	388	false);
5a924b89	389
17926a79 DH	390	/* send the packet with the don't fragment bit set if we currently
17926a79 DH	391	* think it's small enough */
5a924b89 DH	392	if (iov[1].iov_len >= call->peer->maxdata)
	393	goto send_fragmentable;
	394
	395	down_read(&conn->params.local->defrag_sem);
b604dd98 DH	396
	397	sp->hdr.serial = serial;
	398	smp_wmb(); /* Set serial before timestamp */
	399	skb->tstamp = ktime_get_real();
	400
5a924b89 DH	401	/* send the packet by UDP
	402	* - returns -EMSGSIZE if UDP would have to fragment the packet
	403	* to go out of the interface
	404	* - in which case, we'll have processed the ICMP error
	405	* message and update the peer record
	406	*/
	407	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
330bdcfa	408	conn->params.peer->last_tx_at = ktime_get_seconds();
5a924b89 DH	409
5a924b89 DH	410	up_read(&conn->params.local->defrag_sem);
6b47fe1d DH	411	if (ret < 0)
6b47fe1d DH	412	trace_rxrpc_tx_fail(call->debug_id, serial, ret,
4764c0da DH	413	rxrpc_tx_point_call_data_nofrag);
	414	else
	415	trace_rxrpc_tx_packet(call->debug_id, &whdr,
	416	rxrpc_tx_point_call_data_nofrag);
c7e86acf	417	rxrpc_tx_backoff(call, ret);
5a924b89 DH	418	if (ret == -EMSGSIZE)
	419	goto send_fragmentable;
	420
	421	done:
50235c4b	422	if (ret >= 0) {
0d4b103c	423	if (whdr.flags & RXRPC_REQUEST_ACK) {
b604dd98	424	call->peer->rtt_last_req = skb->tstamp;
50235c4b	425	trace_rxrpc_rtt_tx(call, rxrpc_rtt_tx_data, serial);
c410bf01	426	if (call->peer->rtt_count > 1) {
bd1fdf8c DH	427	unsigned long nowj = jiffies, ack_lost_at;
bd1fdf8c DH	428
c410bf01	429	ack_lost_at = rxrpc_get_rto_backoff(call->peer, retrans);
bd1fdf8c DH	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	}
415f44e4	447
c7e86acf DH	448	rxrpc_set_keepalive(call);
	449	} else {
	450	/* Cancel the call if the initial transmission fails,
	451	* particularly if that's due to network routing issues that
	452	* aren't going away anytime soon. The layer above can arrange
	453	* the retransmission.
	454	*/
	455	if (!test_and_set_bit(RXRPC_CALL_BEGAN_RX_TIMER, &call->flags))
	456	rxrpc_set_call_completion(call, RXRPC_CALL_LOCAL_ERROR,
	457	RX_USER_ABORT, ret);
	458	}
415f44e4	459
5a924b89 DH	460	_leave(" = %d [%u]", ret, call->peer->maxdata);
5a924b89 DH	461	return ret;
17926a79 DH	462
	463	send_fragmentable:
	464	/* attempt to send this message with fragmentation enabled */
	465	_debug("send fragment");
	466
985a5c82 DH	467	down_write(&conn->params.local->defrag_sem);
985a5c82 DH	468
b604dd98 DH	469	sp->hdr.serial = serial;
	470	smp_wmb(); /* Set serial before timestamp */
	471	skb->tstamp = ktime_get_real();
	472
985a5c82	473	switch (conn->params.local->srx.transport.family) {
0e631eee	474	case AF_INET6:
985a5c82 DH	475	case AF_INET:
985a5c82 DH	476	opt = IP_PMTUDISC_DONT;
0e631eee DH	477	kernel_setsockopt(conn->params.local->socket,
	478	SOL_IP, IP_MTU_DISCOVER,
	479	(char *)&opt, sizeof(opt));
	480	ret = kernel_sendmsg(conn->params.local->socket, &msg,
	481	iov, 2, len);
	482	conn->params.peer->last_tx_at = ktime_get_seconds();
	483
	484	opt = IP_PMTUDISC_DO;
	485	kernel_setsockopt(conn->params.local->socket,
	486	SOL_IP, IP_MTU_DISCOVER,
	487	(char *)&opt, sizeof(opt));
75b54cb5	488	break;
3427beb6 DH	489
	490	default:
	491	BUG();
17926a79 DH	492	}
17926a79 DH	493
6b47fe1d DH	494	if (ret < 0)
6b47fe1d DH	495	trace_rxrpc_tx_fail(call->debug_id, serial, ret,
4764c0da DH	496	rxrpc_tx_point_call_data_frag);
	497	else
	498	trace_rxrpc_tx_packet(call->debug_id, &whdr,
	499	rxrpc_tx_point_call_data_frag);
c7e86acf	500	rxrpc_tx_backoff(call, ret);
6b47fe1d	501
985a5c82	502	up_write(&conn->params.local->defrag_sem);
5a924b89	503	goto done;
17926a79	504	}
248f219c DH	505
	506	/*
	507	* reject packets through the local endpoint
	508	*/
	509	void rxrpc_reject_packets(struct rxrpc_local *local)
	510	{
1c2bc7b9	511	struct sockaddr_rxrpc srx;
248f219c DH	512	struct rxrpc_skb_priv *sp;
	513	struct rxrpc_wire_header whdr;
	514	struct sk_buff *skb;
	515	struct msghdr msg;
	516	struct kvec iov[2];
	517	size_t size;
	518	__be32 code;
ece64fec	519	int ret, ioc;
248f219c DH	520
	521	_enter("%d", local->debug_id);
	522
	523	iov[0].iov_base = &whdr;
	524	iov[0].iov_len = sizeof(whdr);
	525	iov[1].iov_base = &code;
	526	iov[1].iov_len = sizeof(code);
248f219c	527
1c2bc7b9	528	msg.msg_name = &srx.transport;
248f219c DH	529	msg.msg_control = NULL;
	530	msg.msg_controllen = 0;
	531	msg.msg_flags = 0;
	532
248f219c	533	memset(&whdr, 0, sizeof(whdr));
248f219c DH	534
248f219c DH	535	while ((skb = skb_dequeue(&local->reject_queue))) {
987db9f7	536	rxrpc_see_skb(skb, rxrpc_skb_seen);
248f219c	537	sp = rxrpc_skb(skb);
1c2bc7b9	538
ece64fec DH	539	switch (skb->mark) {
	540	case RXRPC_SKB_MARK_REJECT_BUSY:
	541	whdr.type = RXRPC_PACKET_TYPE_BUSY;
	542	size = sizeof(whdr);
	543	ioc = 1;
	544	break;
	545	case RXRPC_SKB_MARK_REJECT_ABORT:
	546	whdr.type = RXRPC_PACKET_TYPE_ABORT;
	547	code = htonl(skb->priority);
	548	size = sizeof(whdr) + sizeof(code);
	549	ioc = 2;
	550	break;
	551	default:
987db9f7	552	rxrpc_free_skb(skb, rxrpc_skb_freed);
ece64fec DH	553	continue;
	554	}
	555
5a790b73	556	if (rxrpc_extract_addr_from_skb(&srx, skb) == 0) {
1c2bc7b9 DH	557	msg.msg_namelen = srx.transport_len;
1c2bc7b9 DH	558
248f219c DH	559	whdr.epoch = htonl(sp->hdr.epoch);
	560	whdr.cid = htonl(sp->hdr.cid);
	561	whdr.callNumber = htonl(sp->hdr.callNumber);
	562	whdr.serviceId = htons(sp->hdr.serviceId);
	563	whdr.flags = sp->hdr.flags;
	564	whdr.flags ^= RXRPC_CLIENT_INITIATED;
	565	whdr.flags &= RXRPC_CLIENT_INITIATED;
	566
d6672a5a Y	567	ret = kernel_sendmsg(local->socket, &msg,
d6672a5a Y	568	iov, ioc, size);
6b47fe1d DH	569	if (ret < 0)
6b47fe1d DH	570	trace_rxrpc_tx_fail(local->debug_id, 0, ret,
4764c0da DH	571	rxrpc_tx_point_reject);
	572	else
	573	trace_rxrpc_tx_packet(local->debug_id, &whdr,
	574	rxrpc_tx_point_reject);
248f219c DH	575	}
248f219c DH	576
987db9f7	577	rxrpc_free_skb(skb, rxrpc_skb_freed);
248f219c DH	578	}
	579
	580	_leave("");
	581	}
ace45bec DH	582
	583	/*
	584	* Send a VERSION reply to a peer as a keepalive.
	585	*/
	586	void rxrpc_send_keepalive(struct rxrpc_peer *peer)
	587	{
	588	struct rxrpc_wire_header whdr;
	589	struct msghdr msg;
	590	struct kvec iov[2];
	591	size_t len;
	592	int ret;
	593
	594	_enter("");
	595
	596	msg.msg_name = &peer->srx.transport;
	597	msg.msg_namelen = peer->srx.transport_len;
	598	msg.msg_control = NULL;
	599	msg.msg_controllen = 0;
	600	msg.msg_flags = 0;
	601
	602	whdr.epoch = htonl(peer->local->rxnet->epoch);
	603	whdr.cid = 0;
	604	whdr.callNumber = 0;
	605	whdr.seq = 0;
	606	whdr.serial = 0;
	607	whdr.type = RXRPC_PACKET_TYPE_VERSION; /* Not client-initiated */
	608	whdr.flags = RXRPC_LAST_PACKET;
	609	whdr.userStatus = 0;
	610	whdr.securityIndex = 0;
	611	whdr._rsvd = 0;
	612	whdr.serviceId = 0;
	613
	614	iov[0].iov_base = &whdr;
	615	iov[0].iov_len = sizeof(whdr);
	616	iov[1].iov_base = (char *)rxrpc_keepalive_string;
	617	iov[1].iov_len = sizeof(rxrpc_keepalive_string);
	618
	619	len = iov[0].iov_len + iov[1].iov_len;
	620
	621	_proto("Tx VERSION (keepalive)");
	622
	623	ret = kernel_sendmsg(peer->local->socket, &msg, iov, 2, len);
	624	if (ret < 0)
6b47fe1d	625	trace_rxrpc_tx_fail(peer->debug_id, 0, ret,
4764c0da DH	626	rxrpc_tx_point_version_keepalive);
	627	else
	628	trace_rxrpc_tx_packet(peer->debug_id, &whdr,
	629	rxrpc_tx_point_version_keepalive);
ace45bec	630
330bdcfa	631	peer->last_tx_at = ktime_get_seconds();
ace45bec DH	632	_leave("");
ace45bec DH	633	}