[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;
};

/*
 * 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)
{
	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;
	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, serial,
			   ntohl(pkt->ack.firstPacket),
			   ntohl(pkt->ack.serial),
			   pkt->ack.reason, pkt->ack.nAcks);

	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);
	if (ping)
		call->ping_time = ktime_get_real();

	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);
		}
	}

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;

	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));

	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) &&
	    (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);

	up_read(&conn->params.local->defrag_sem);
	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);
		}
	}
	_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);

			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, 1, iov[0].iov_len);

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

	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;

	_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;

			kernel_sendmsg(local->socket, &msg, iov, 2, size);
		}

		rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
	}

	_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
8d94aa38 DH	35	/*
	36	* Fill out an ACK packet.
	37	*/
1457cc4c DH	38	static size_t rxrpc_fill_out_ack(struct rxrpc_connection *conn,
1457cc4c DH	39	struct rxrpc_call *call,
26cb02aa	40	struct rxrpc_ack_buffer *pkt,
805b21b9	41	rxrpc_seq_t *_hard_ack,
a5af7e1f DH	42	rxrpc_seq_t *_top,
a5af7e1f DH	43	u8 reason)
8d94aa38	44	{
f3639df2	45	rxrpc_serial_t serial;
248f219c DH	46	rxrpc_seq_t hard_ack, top, seq;
248f219c DH	47	int ix;
8d94aa38 DH	48	u32 mtu, jmax;
	49	u8 *ackp = pkt->acks;
	50
248f219c	51	/* Barrier against rxrpc_input_data(). */
f3639df2	52	serial = call->ackr_serial;
248f219c DH	53	hard_ack = READ_ONCE(call->rx_hard_ack);
248f219c DH	54	top = smp_load_acquire(&call->rx_top);
805b21b9 DH	55	*_hard_ack = hard_ack;
805b21b9 DH	56	*_top = top;
248f219c	57
8d94aa38	58	pkt->ack.bufferSpace = htons(8);
248f219c DH	59	pkt->ack.maxSkew = htons(call->ackr_skew);
248f219c DH	60	pkt->ack.firstPacket = htonl(hard_ack + 1);
8d94aa38	61	pkt->ack.previousPacket = htonl(call->ackr_prev_seq);
f3639df2	62	pkt->ack.serial = htonl(serial);
a5af7e1f	63	pkt->ack.reason = reason;
248f219c DH	64	pkt->ack.nAcks = top - hard_ack;
248f219c DH	65
a5af7e1f	66	if (reason == RXRPC_ACK_PING)
8e83134d DH	67	pkt->whdr.flags \|= RXRPC_REQUEST_ACK;
8e83134d DH	68
248f219c DH	69	if (after(top, hard_ack)) {
	70	seq = hard_ack + 1;
	71	do {
	72	ix = seq & RXRPC_RXTX_BUFF_MASK;
	73	if (call->rxtx_buffer[ix])
	74	*ackp++ = RXRPC_ACK_TYPE_ACK;
	75	else
	76	*ackp++ = RXRPC_ACK_TYPE_NACK;
	77	seq++;
	78	} while (before_eq(seq, top));
	79	}
8d94aa38	80
1457cc4c DH	81	mtu = conn->params.peer->if_mtu;
1457cc4c DH	82	mtu -= conn->params.peer->hdrsize;
75e42126	83	jmax = (call->nr_jumbo_bad > 3) ? 1 : rxrpc_rx_jumbo_max;
8d94aa38 DH	84	pkt->ackinfo.rxMTU = htonl(rxrpc_rx_mtu);
8d94aa38 DH	85	pkt->ackinfo.maxMTU = htonl(mtu);
75e42126	86	pkt->ackinfo.rwind = htonl(call->rx_winsize);
8d94aa38 DH	87	pkt->ackinfo.jumbo_max = htonl(jmax);
	88
	89	*ackp++ = 0;
	90	*ackp++ = 0;
	91	*ackp++ = 0;
248f219c	92	return top - hard_ack + 3;
8d94aa38 DH	93	}
	94
	95	/*
26cb02aa	96	* Send an ACK call packet.
8d94aa38	97	*/
a5af7e1f	98	int rxrpc_send_ack_packet(struct rxrpc_call *call, bool ping)
8d94aa38 DH	99	{
8d94aa38 DH	100	struct rxrpc_connection *conn = NULL;
26cb02aa	101	struct rxrpc_ack_buffer *pkt;
8d94aa38 DH	102	struct msghdr msg;
	103	struct kvec iov[2];
	104	rxrpc_serial_t serial;
805b21b9	105	rxrpc_seq_t hard_ack, top;
8d94aa38	106	size_t len, n;
26cb02aa	107	int ret;
a5af7e1f	108	u8 reason;
8d94aa38 DH	109
	110	spin_lock_bh(&call->lock);
	111	if (call->conn)
	112	conn = rxrpc_get_connection_maybe(call->conn);
	113	spin_unlock_bh(&call->lock);
	114	if (!conn)
	115	return -ECONNRESET;
	116
	117	pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
	118	if (!pkt) {
	119	rxrpc_put_connection(conn);
	120	return -ENOMEM;
	121	}
	122
8d94aa38 DH	123	msg.msg_name = &call->peer->srx.transport;
	124	msg.msg_namelen = call->peer->srx.transport_len;
	125	msg.msg_control = NULL;
	126	msg.msg_controllen = 0;
	127	msg.msg_flags = 0;
	128
	129	pkt->whdr.epoch = htonl(conn->proto.epoch);
	130	pkt->whdr.cid = htonl(call->cid);
	131	pkt->whdr.callNumber = htonl(call->call_id);
	132	pkt->whdr.seq = 0;
26cb02aa DH	133	pkt->whdr.type = RXRPC_PACKET_TYPE_ACK;
26cb02aa DH	134	pkt->whdr.flags = RXRPC_SLOW_START_OK \| conn->out_clientflag;
8d94aa38 DH	135	pkt->whdr.userStatus = 0;
	136	pkt->whdr.securityIndex = call->security_ix;
	137	pkt->whdr._rsvd = 0;
	138	pkt->whdr.serviceId = htons(call->service_id);
	139
26cb02aa	140	spin_lock_bh(&call->lock);
a5af7e1f DH	141	if (ping) {
	142	reason = RXRPC_ACK_PING;
	143	} else {
	144	reason = call->ackr_reason;
	145	if (!call->ackr_reason) {
	146	spin_unlock_bh(&call->lock);
	147	ret = 0;
	148	goto out;
	149	}
	150	call->ackr_reason = 0;
8d94aa38	151	}
1457cc4c	152	n = rxrpc_fill_out_ack(conn, call, pkt, &hard_ack, &top, reason);
26cb02aa DH	153
	154	spin_unlock_bh(&call->lock);
	155
	156	iov[0].iov_base = pkt;
	157	iov[0].iov_len = sizeof(pkt->whdr) + sizeof(pkt->ack) + n;
	158	iov[1].iov_base = &pkt->ackinfo;
	159	iov[1].iov_len = sizeof(pkt->ackinfo);
	160	len = iov[0].iov_len + iov[1].iov_len;
8d94aa38	161
b86e218e DH	162	serial = atomic_inc_return(&conn->serial);
b86e218e DH	163	pkt->whdr.serial = htonl(serial);
26cb02aa DH	164	trace_rxrpc_tx_ack(call, serial,
	165	ntohl(pkt->ack.firstPacket),
	166	ntohl(pkt->ack.serial),
	167	pkt->ack.reason, pkt->ack.nAcks);
b86e218e	168
8e83134d	169	if (ping) {
a5af7e1f	170	call->ping_serial = serial;
8e83134d DH	171	smp_wmb();
	172	/* We need to stick a time in before we send the packet in case
	173	* the reply gets back before kernel_sendmsg() completes - but
	174	* asking UDP to send the packet can take a relatively long
	175	* time, so we update the time after, on the assumption that
	176	* the packet transmission is more likely to happen towards the
	177	* end of the kernel_sendmsg() call.
	178	*/
a5af7e1f	179	call->ping_time = ktime_get_real();
8e83134d DH	180	set_bit(RXRPC_CALL_PINGING, &call->flags);
	181	trace_rxrpc_rtt_tx(call, rxrpc_rtt_tx_ping, serial);
	182	}
26cb02aa DH	183
26cb02aa DH	184	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
8e83134d	185	if (ping)
a5af7e1f	186	call->ping_time = ktime_get_real();
8d94aa38	187
26cb02aa	188	if (call->state < RXRPC_CALL_COMPLETE) {
805b21b9	189	if (ret < 0) {
a5af7e1f DH	190	if (ping)
a5af7e1f DH	191	clear_bit(RXRPC_CALL_PINGING, &call->flags);
248f219c DH	192	rxrpc_propose_ACK(call, pkt->ack.reason,
	193	ntohs(pkt->ack.maxSkew),
	194	ntohl(pkt->ack.serial),
9c7ad434 DH	195	true, true,
9c7ad434 DH	196	rxrpc_propose_ack_retry_tx);
805b21b9 DH	197	} else {
	198	spin_lock_bh(&call->lock);
	199	if (after(hard_ack, call->ackr_consumed))
	200	call->ackr_consumed = hard_ack;
	201	if (after(top, call->ackr_seen))
	202	call->ackr_seen = top;
	203	spin_unlock_bh(&call->lock);
248f219c DH	204	}
	205	}
	206
8d94aa38 DH	207	out:
	208	rxrpc_put_connection(conn);
	209	kfree(pkt);
	210	return ret;
	211	}
	212
26cb02aa DH	213	/*
	214	* Send an ABORT call packet.
	215	*/
	216	int rxrpc_send_abort_packet(struct rxrpc_call *call)
	217	{
	218	struct rxrpc_connection *conn = NULL;
	219	struct rxrpc_abort_buffer pkt;
	220	struct msghdr msg;
	221	struct kvec iov[1];
	222	rxrpc_serial_t serial;
	223	int ret;
	224
	225	spin_lock_bh(&call->lock);
	226	if (call->conn)
	227	conn = rxrpc_get_connection_maybe(call->conn);
	228	spin_unlock_bh(&call->lock);
	229	if (!conn)
	230	return -ECONNRESET;
	231
	232	msg.msg_name = &call->peer->srx.transport;
	233	msg.msg_namelen = call->peer->srx.transport_len;
	234	msg.msg_control = NULL;
	235	msg.msg_controllen = 0;
	236	msg.msg_flags = 0;
	237
	238	pkt.whdr.epoch = htonl(conn->proto.epoch);
	239	pkt.whdr.cid = htonl(call->cid);
	240	pkt.whdr.callNumber = htonl(call->call_id);
	241	pkt.whdr.seq = 0;
	242	pkt.whdr.type = RXRPC_PACKET_TYPE_ABORT;
	243	pkt.whdr.flags = conn->out_clientflag;
	244	pkt.whdr.userStatus = 0;
	245	pkt.whdr.securityIndex = call->security_ix;
	246	pkt.whdr._rsvd = 0;
	247	pkt.whdr.serviceId = htons(call->service_id);
	248	pkt.abort_code = htonl(call->abort_code);
	249
	250	iov[0].iov_base = &pkt;
	251	iov[0].iov_len = sizeof(pkt);
	252
	253	serial = atomic_inc_return(&conn->serial);
	254	pkt.whdr.serial = htonl(serial);
	255
	256	ret = kernel_sendmsg(conn->params.local->socket,
	257	&msg, iov, 1, sizeof(pkt));
	258
	259	rxrpc_put_connection(conn);
	260	return ret;
	261	}
	262
17926a79 DH	263	/*
	264	* send a packet through the transport endpoint
	265	*/
a1767077 DH	266	int rxrpc_send_data_packet(struct rxrpc_call call, struct sk_buff skb,
a1767077 DH	267	bool retrans)
17926a79	268	{
5a924b89 DH	269	struct rxrpc_connection *conn = call->conn;
	270	struct rxrpc_wire_header whdr;
	271	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
17926a79	272	struct msghdr msg;
5a924b89 DH	273	struct kvec iov[2];
	274	rxrpc_serial_t serial;
	275	size_t len;
a1767077	276	bool lost = false;
17926a79 DH	277	int ret, opt;
	278
	279	_enter(",{%d}", skb->len);
	280
5a924b89 DH	281	/* Each transmission of a Tx packet needs a new serial number */
5a924b89 DH	282	serial = atomic_inc_return(&conn->serial);
17926a79	283
5a924b89 DH	284	whdr.epoch = htonl(conn->proto.epoch);
	285	whdr.cid = htonl(call->cid);
	286	whdr.callNumber = htonl(call->call_id);
	287	whdr.seq = htonl(sp->hdr.seq);
	288	whdr.serial = htonl(serial);
	289	whdr.type = RXRPC_PACKET_TYPE_DATA;
	290	whdr.flags = sp->hdr.flags;
	291	whdr.userStatus = 0;
	292	whdr.securityIndex = call->security_ix;
	293	whdr._rsvd = htons(sp->hdr._rsvd);
	294	whdr.serviceId = htons(call->service_id);
	295
4e255721 DH	296	if (test_bit(RXRPC_CONN_PROBING_FOR_UPGRADE, &conn->flags) &&
	297	sp->hdr.seq == 1)
	298	whdr.userStatus = RXRPC_USERSTATUS_SERVICE_UPGRADE;
	299
5a924b89 DH	300	iov[0].iov_base = &whdr;
	301	iov[0].iov_len = sizeof(whdr);
	302	iov[1].iov_base = skb->head;
	303	iov[1].iov_len = skb->len;
	304	len = iov[0].iov_len + iov[1].iov_len;
	305
	306	msg.msg_name = &call->peer->srx.transport;
	307	msg.msg_namelen = call->peer->srx.transport_len;
17926a79 DH	308	msg.msg_control = NULL;
	309	msg.msg_controllen = 0;
	310	msg.msg_flags = 0;
	311
57494343 DH	312	/* If our RTT cache needs working on, request an ACK. Also request
	313	* ACKs if a DATA packet appears to have been lost.
	314	*/
bf7d620a DH	315	if (!(sp->hdr.flags & RXRPC_LAST_PACKET) &&
	316	(retrans \|\|
	317	call->cong_mode == RXRPC_CALL_SLOW_START \|\|
	318	(call->peer->rtt_usage < 3 && sp->hdr.seq & 1) \|\|
	319	ktime_before(ktime_add_ms(call->peer->rtt_last_req, 1000),
	320	ktime_get_real())))
0d4b103c DH	321	whdr.flags \|= RXRPC_REQUEST_ACK;
0d4b103c DH	322
8a681c36 DH	323	if (IS_ENABLED(CONFIG_AF_RXRPC_INJECT_LOSS)) {
	324	static int lose;
	325	if ((lose++ & 7) == 7) {
a1767077 DH	326	ret = 0;
	327	lost = true;
	328	goto done;
8a681c36 DH	329	}
	330	}
	331
5a924b89 DH	332	_proto("Tx DATA %%%u { #%u }", serial, sp->hdr.seq);
5a924b89 DH	333
17926a79 DH	334	/* send the packet with the don't fragment bit set if we currently
17926a79 DH	335	* think it's small enough */
5a924b89 DH	336	if (iov[1].iov_len >= call->peer->maxdata)
	337	goto send_fragmentable;
	338
	339	down_read(&conn->params.local->defrag_sem);
	340	/* send the packet by UDP
	341	* - returns -EMSGSIZE if UDP would have to fragment the packet
	342	* to go out of the interface
	343	* - in which case, we'll have processed the ICMP error
	344	* message and update the peer record
	345	*/
	346	ret = kernel_sendmsg(conn->params.local->socket, &msg, iov, 2, len);
	347
	348	up_read(&conn->params.local->defrag_sem);
	349	if (ret == -EMSGSIZE)
	350	goto send_fragmentable;
	351
	352	done:
a1767077 DH	353	trace_rxrpc_tx_data(call, sp->hdr.seq, serial, whdr.flags,
a1767077 DH	354	retrans, lost);
50235c4b	355	if (ret >= 0) {
0d4b103c DH	356	ktime_t now = ktime_get_real();
0d4b103c DH	357	skb->tstamp = now;
50235c4b	358	smp_wmb();
5a924b89	359	sp->hdr.serial = serial;
0d4b103c DH	360	if (whdr.flags & RXRPC_REQUEST_ACK) {
0d4b103c DH	361	call->peer->rtt_last_req = now;
50235c4b	362	trace_rxrpc_rtt_tx(call, rxrpc_rtt_tx_data, serial);
0d4b103c	363	}
17926a79	364	}
5a924b89 DH	365	_leave(" = %d [%u]", ret, call->peer->maxdata);
5a924b89 DH	366	return ret;
17926a79 DH	367
	368	send_fragmentable:
	369	/* attempt to send this message with fragmentation enabled */
	370	_debug("send fragment");
	371
985a5c82 DH	372	down_write(&conn->params.local->defrag_sem);
	373
	374	switch (conn->params.local->srx.transport.family) {
	375	case AF_INET:
	376	opt = IP_PMTUDISC_DONT;
	377	ret = kernel_setsockopt(conn->params.local->socket,
	378	SOL_IP, IP_MTU_DISCOVER,
	379	(char *)&opt, sizeof(opt));
	380	if (ret == 0) {
5a924b89 DH	381	ret = kernel_sendmsg(conn->params.local->socket, &msg,
5a924b89 DH	382	iov, 2, len);
985a5c82 DH	383
	384	opt = IP_PMTUDISC_DO;
	385	kernel_setsockopt(conn->params.local->socket, SOL_IP,
	386	IP_MTU_DISCOVER,
	387	(char *)&opt, sizeof(opt));
	388	}
	389	break;
75b54cb5	390
d1912747	391	#ifdef CONFIG_AF_RXRPC_IPV6
75b54cb5 DH	392	case AF_INET6:
	393	opt = IPV6_PMTUDISC_DONT;
	394	ret = kernel_setsockopt(conn->params.local->socket,
	395	SOL_IPV6, IPV6_MTU_DISCOVER,
	396	(char *)&opt, sizeof(opt));
	397	if (ret == 0) {
	398	ret = kernel_sendmsg(conn->params.local->socket, &msg,
	399	iov, 1, iov[0].iov_len);
	400
	401	opt = IPV6_PMTUDISC_DO;
	402	kernel_setsockopt(conn->params.local->socket,
	403	SOL_IPV6, IPV6_MTU_DISCOVER,
	404	(char *)&opt, sizeof(opt));
	405	}
	406	break;
d1912747	407	#endif
17926a79 DH	408	}
17926a79 DH	409
985a5c82	410	up_write(&conn->params.local->defrag_sem);
5a924b89	411	goto done;
17926a79	412	}
248f219c DH	413
	414	/*
	415	* reject packets through the local endpoint
	416	*/
	417	void rxrpc_reject_packets(struct rxrpc_local *local)
	418	{
1c2bc7b9	419	struct sockaddr_rxrpc srx;
248f219c DH	420	struct rxrpc_skb_priv *sp;
	421	struct rxrpc_wire_header whdr;
	422	struct sk_buff *skb;
	423	struct msghdr msg;
	424	struct kvec iov[2];
	425	size_t size;
	426	__be32 code;
	427
	428	_enter("%d", local->debug_id);
	429
	430	iov[0].iov_base = &whdr;
	431	iov[0].iov_len = sizeof(whdr);
	432	iov[1].iov_base = &code;
	433	iov[1].iov_len = sizeof(code);
	434	size = sizeof(whdr) + sizeof(code);
	435
1c2bc7b9	436	msg.msg_name = &srx.transport;
248f219c DH	437	msg.msg_control = NULL;
	438	msg.msg_controllen = 0;
	439	msg.msg_flags = 0;
	440
248f219c DH	441	memset(&whdr, 0, sizeof(whdr));
	442	whdr.type = RXRPC_PACKET_TYPE_ABORT;
	443
	444	while ((skb = skb_dequeue(&local->reject_queue))) {
71f3ca40	445	rxrpc_see_skb(skb, rxrpc_skb_rx_seen);
248f219c	446	sp = rxrpc_skb(skb);
1c2bc7b9	447
7b674e39	448	if (rxrpc_extract_addr_from_skb(local, &srx, skb) == 0) {
1c2bc7b9 DH	449	msg.msg_namelen = srx.transport_len;
1c2bc7b9 DH	450
248f219c DH	451	code = htonl(skb->priority);
	452
	453	whdr.epoch = htonl(sp->hdr.epoch);
	454	whdr.cid = htonl(sp->hdr.cid);
	455	whdr.callNumber = htonl(sp->hdr.callNumber);
	456	whdr.serviceId = htons(sp->hdr.serviceId);
	457	whdr.flags = sp->hdr.flags;
	458	whdr.flags ^= RXRPC_CLIENT_INITIATED;
	459	whdr.flags &= RXRPC_CLIENT_INITIATED;
	460
	461	kernel_sendmsg(local->socket, &msg, iov, 2, size);
248f219c DH	462	}
248f219c DH	463
71f3ca40	464	rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
248f219c DH	465	}
	466
	467	_leave("");
	468	}