Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 2278 insertions, 0 deletions

diff --git a/net/rxrpc/call.c b/net/rxrpc/call.c
new file mode 100644
index 000000000000..5cfd4cadee42
--- /dev/null
+++ b/net/rxrpc/call.c
@@ -0,0 +1,2278 @@
+/* call.c: Rx call routines
+ *
+ * Copyright (C) 2002 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.
+ */
+
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <rxrpc/rxrpc.h>
+#include <rxrpc/transport.h>
+#include <rxrpc/peer.h>
+#include <rxrpc/connection.h>
+#include <rxrpc/call.h>
+#include <rxrpc/message.h>
+#include "internal.h"
+
+__RXACCT_DECL(atomic_t rxrpc_call_count);
+__RXACCT_DECL(atomic_t rxrpc_message_count);
+
+LIST_HEAD(rxrpc_calls);
+DECLARE_RWSEM(rxrpc_calls_sem);
+
+unsigned rxrpc_call_rcv_timeout			= HZ/3;
+static unsigned rxrpc_call_acks_timeout		= HZ/3;
+static unsigned rxrpc_call_dfr_ack_timeout	= HZ/20;
+static unsigned short rxrpc_call_max_resend	= HZ/10;
+
+const char *rxrpc_call_states[] = {
+	"COMPLETE",
+	"ERROR",
+	"SRVR_RCV_OPID",
+	"SRVR_RCV_ARGS",
+	"SRVR_GOT_ARGS",
+	"SRVR_SND_REPLY",
+	"SRVR_RCV_FINAL_ACK",
+	"CLNT_SND_ARGS",
+	"CLNT_RCV_REPLY",
+	"CLNT_GOT_REPLY"
+};
+
+const char *rxrpc_call_error_states[] = {
+	"NO_ERROR",
+	"LOCAL_ABORT",
+	"PEER_ABORT",
+	"LOCAL_ERROR",
+	"REMOTE_ERROR"
+};
+
+const char *rxrpc_pkts[] = {
+	"?00",
+	"data", "ack", "busy", "abort", "ackall", "chall", "resp", "debug",
+	"?09", "?10", "?11", "?12", "?13", "?14", "?15"
+};
+
+static const char *rxrpc_acks[] = {
+	"---", "REQ", "DUP", "SEQ", "WIN", "MEM", "PNG", "PNR", "DLY", "IDL",
+	"-?-"
+};
+
+static const char _acktype[] = "NA-";
+
+static void rxrpc_call_receive_packet(struct rxrpc_call *call);
+static void rxrpc_call_receive_data_packet(struct rxrpc_call *call,
+					   struct rxrpc_message *msg);
+static void rxrpc_call_receive_ack_packet(struct rxrpc_call *call,
+					  struct rxrpc_message *msg);
+static void rxrpc_call_definitively_ACK(struct rxrpc_call *call,
+					rxrpc_seq_t higest);
+static void rxrpc_call_resend(struct rxrpc_call *call, rxrpc_seq_t highest);
+static int __rxrpc_call_read_data(struct rxrpc_call *call);
+
+static int rxrpc_call_record_ACK(struct rxrpc_call *call,
+				 struct rxrpc_message *msg,
+				 rxrpc_seq_t seq,
+				 size_t count);
+
+static int rxrpc_call_flush(struct rxrpc_call *call);
+
+#define _state(call) \
+	_debug("[[[ state %s ]]]", rxrpc_call_states[call->app_call_state]);
+
+static void rxrpc_call_default_attn_func(struct rxrpc_call *call)
+{
+	wake_up(&call->waitq);
+}
+
+static void rxrpc_call_default_error_func(struct rxrpc_call *call)
+{
+	wake_up(&call->waitq);
+}
+
+static void rxrpc_call_default_aemap_func(struct rxrpc_call *call)
+{
+	switch (call->app_err_state) {
+	case RXRPC_ESTATE_LOCAL_ABORT:
+		call->app_abort_code = -call->app_errno;
+	case RXRPC_ESTATE_PEER_ABORT:
+		call->app_errno = -ECONNABORTED;
+	default:
+		break;
+	}
+}
+
+static void __rxrpc_call_acks_timeout(unsigned long _call)
+{
+	struct rxrpc_call *call = (struct rxrpc_call *) _call;
+
+	_debug("ACKS TIMEOUT %05lu", jiffies - call->cjif);
+
+	call->flags |= RXRPC_CALL_ACKS_TIMO;
+	rxrpc_krxiod_queue_call(call);
+}
+
+static void __rxrpc_call_rcv_timeout(unsigned long _call)
+{
+	struct rxrpc_call *call = (struct rxrpc_call *) _call;
+
+	_debug("RCV TIMEOUT %05lu", jiffies - call->cjif);
+
+	call->flags |= RXRPC_CALL_RCV_TIMO;
+	rxrpc_krxiod_queue_call(call);
+}
+
+static void __rxrpc_call_ackr_timeout(unsigned long _call)
+{
+	struct rxrpc_call *call = (struct rxrpc_call *) _call;
+
+	_debug("ACKR TIMEOUT %05lu",jiffies - call->cjif);
+
+	call->flags |= RXRPC_CALL_ACKR_TIMO;
+	rxrpc_krxiod_queue_call(call);
+}
+
+/*****************************************************************************/
+/*
+ * calculate a timeout based on an RTT value
+ */
+static inline unsigned long __rxrpc_rtt_based_timeout(struct rxrpc_call *call,
+						      unsigned long val)
+{
+	unsigned long expiry = call->conn->peer->rtt / (1000000 / HZ);
+
+	expiry += 10;
+	if (expiry < HZ / 25)
+		expiry = HZ / 25;
+	if (expiry > HZ)
+		expiry = HZ;
+
+	_leave(" = %lu jiffies", expiry);
+	return jiffies + expiry;
+} /* end __rxrpc_rtt_based_timeout() */
+
+/*****************************************************************************/
+/*
+ * create a new call record
+ */
+static inline int __rxrpc_create_call(struct rxrpc_connection *conn,
+				      struct rxrpc_call **_call)
+{
+	struct rxrpc_call *call;
+
+	_enter("%p", conn);
+
+	/* allocate and initialise a call record */
+	call = (struct rxrpc_call *) get_zeroed_page(GFP_KERNEL);
+	if (!call) {
+		_leave(" ENOMEM");
+		return -ENOMEM;
+	}
+
+	atomic_set(&call->usage, 1);
+
+	init_waitqueue_head(&call->waitq);
+	spin_lock_init(&call->lock);
+	INIT_LIST_HEAD(&call->link);
+	INIT_LIST_HEAD(&call->acks_pendq);
+	INIT_LIST_HEAD(&call->rcv_receiveq);
+	INIT_LIST_HEAD(&call->rcv_krxiodq_lk);
+	INIT_LIST_HEAD(&call->app_readyq);
+	INIT_LIST_HEAD(&call->app_unreadyq);
+	INIT_LIST_HEAD(&call->app_link);
+	INIT_LIST_HEAD(&call->app_attn_link);
+
+	init_timer(&call->acks_timeout);
+	call->acks_timeout.data = (unsigned long) call;
+	call->acks_timeout.function = __rxrpc_call_acks_timeout;
+
+	init_timer(&call->rcv_timeout);
+	call->rcv_timeout.data = (unsigned long) call;
+	call->rcv_timeout.function = __rxrpc_call_rcv_timeout;
+
+	init_timer(&call->ackr_dfr_timo);
+	call->ackr_dfr_timo.data = (unsigned long) call;
+	call->ackr_dfr_timo.function = __rxrpc_call_ackr_timeout;
+
+	call->conn = conn;
+	call->ackr_win_bot = 1;
+	call->ackr_win_top = call->ackr_win_bot + RXRPC_CALL_ACK_WINDOW_SIZE - 1;
+	call->ackr_prev_seq = 0;
+	call->app_mark = RXRPC_APP_MARK_EOF;
+	call->app_attn_func = rxrpc_call_default_attn_func;
+	call->app_error_func = rxrpc_call_default_error_func;
+	call->app_aemap_func = rxrpc_call_default_aemap_func;
+	call->app_scr_alloc = call->app_scratch;
+
+	call->cjif = jiffies;
+
+	_leave(" = 0 (%p)", call);
+
+	*_call = call;
+
+	return 0;
+} /* end __rxrpc_create_call() */
+
+/*****************************************************************************/
+/*
+ * create a new call record for outgoing calls
+ */
+int rxrpc_create_call(struct rxrpc_connection *conn,
+		      rxrpc_call_attn_func_t attn,
+		      rxrpc_call_error_func_t error,
+		      rxrpc_call_aemap_func_t aemap,
+		      struct rxrpc_call **_call)
+{
+	DECLARE_WAITQUEUE(myself, current);
+
+	struct rxrpc_call *call;
+	int ret, cix, loop;
+
+	_enter("%p", conn);
+
+	/* allocate and initialise a call record */
+	ret = __rxrpc_create_call(conn, &call);
+	if (ret < 0) {
+		_leave(" = %d", ret);
+		return ret;
+	}
+
+	call->app_call_state = RXRPC_CSTATE_CLNT_SND_ARGS;
+	if (attn)
+		call->app_attn_func = attn;
+	if (error)
+		call->app_error_func = error;
+	if (aemap)
+		call->app_aemap_func = aemap;
+
+	_state(call);
+
+	spin_lock(&conn->lock);
+	set_current_state(TASK_INTERRUPTIBLE);
+	add_wait_queue(&conn->chanwait, &myself);
+
+ try_again:
+	/* try to find an unused channel */
+	for (cix = 0; cix < 4; cix++)
+		if (!conn->channels[cix])
+			goto obtained_chan;
+
+	/* no free channels - wait for one to become available */
+	ret = -EINTR;
+	if (signal_pending(current))
+		goto error_unwait;
+
+	spin_unlock(&conn->lock);
+
+	schedule();
+	set_current_state(TASK_INTERRUPTIBLE);
+
+	spin_lock(&conn->lock);
+	goto try_again;
+
+	/* got a channel - now attach to the connection */
+ obtained_chan:
+	remove_wait_queue(&conn->chanwait, &myself);
+	set_current_state(TASK_RUNNING);
+
+	/* concoct a unique call number */
+ next_callid:
+	call->call_id = htonl(++conn->call_counter);
+	for (loop = 0; loop < 4; loop++)
+		if (conn->channels[loop] &&
+		    conn->channels[loop]->call_id == call->call_id)
+			goto next_callid;
+
+	rxrpc_get_connection(conn);
+	conn->channels[cix] = call; /* assign _after_ done callid check loop */
+	do_gettimeofday(&conn->atime);
+	call->chan_ix = htonl(cix);
+
+	spin_unlock(&conn->lock);
+
+	down_write(&rxrpc_calls_sem);
+	list_add_tail(&call->call_link, &rxrpc_calls);
+	up_write(&rxrpc_calls_sem);
+
+	__RXACCT(atomic_inc(&rxrpc_call_count));
+	*_call = call;
+
+	_leave(" = 0 (call=%p cix=%u)", call, cix);
+	return 0;
+
+ error_unwait:
+	remove_wait_queue(&conn->chanwait, &myself);
+	set_current_state(TASK_RUNNING);
+	spin_unlock(&conn->lock);
+
+	free_page((unsigned long) call);
+	_leave(" = %d", ret);
+	return ret;
+} /* end rxrpc_create_call() */
+
+/*****************************************************************************/
+/*
+ * create a new call record for incoming calls
+ */
+int rxrpc_incoming_call(struct rxrpc_connection *conn,
+			struct rxrpc_message *msg,
+			struct rxrpc_call **_call)
+{
+	struct rxrpc_call *call;
+	unsigned cix;
+	int ret;
+
+	cix = ntohl(msg->hdr.cid) & RXRPC_CHANNELMASK;
+
+	_enter("%p,%u,%u", conn, ntohl(msg->hdr.callNumber), cix);
+
+	/* allocate and initialise a call record */
+	ret = __rxrpc_create_call(conn, &call);
+	if (ret < 0) {
+		_leave(" = %d", ret);
+		return ret;
+	}
+
+	call->pkt_rcv_count = 1;
+	call->app_call_state = RXRPC_CSTATE_SRVR_RCV_OPID;
+	call->app_mark = sizeof(uint32_t);
+
+	_state(call);
+
+	/* attach to the connection */
+	ret = -EBUSY;
+	call->chan_ix = htonl(cix);
+	call->call_id = msg->hdr.callNumber;
+
+	spin_lock(&conn->lock);
+
+	if (!conn->channels[cix] ||
+	    conn->channels[cix]->app_call_state == RXRPC_CSTATE_COMPLETE ||
+	    conn->channels[cix]->app_call_state == RXRPC_CSTATE_ERROR
+	    ) {
+		conn->channels[cix] = call;
+		rxrpc_get_connection(conn);
+		ret = 0;
+	}
+
+	spin_unlock(&conn->lock);
+
+	if (ret < 0) {
+		free_page((unsigned long) call);
+		call = NULL;
+	}
+
+	if (ret == 0) {
+		down_write(&rxrpc_calls_sem);
+		list_add_tail(&call->call_link, &rxrpc_calls);
+		up_write(&rxrpc_calls_sem);
+		__RXACCT(atomic_inc(&rxrpc_call_count));
+		*_call = call;
+	}
+
+	_leave(" = %d [%p]", ret, call);
+	return ret;
+} /* end rxrpc_incoming_call() */
+
+/*****************************************************************************/
+/*
+ * free a call record
+ */
+void rxrpc_put_call(struct rxrpc_call *call)
+{
+	struct rxrpc_connection *conn = call->conn;
+	struct rxrpc_message *msg;
+
+	_enter("%p{u=%d}",call,atomic_read(&call->usage));
+
+	/* sanity check */
+	if (atomic_read(&call->usage) <= 0)
+		BUG();
+
+	/* to prevent a race, the decrement and the de-list must be effectively
+	 * atomic */
+	spin_lock(&conn->lock);
+	if (likely(!atomic_dec_and_test(&call->usage))) {
+		spin_unlock(&conn->lock);
+		_leave("");
+		return;
+	}
+
+	if (conn->channels[ntohl(call->chan_ix)] == call)
+		conn->channels[ntohl(call->chan_ix)] = NULL;
+
+	spin_unlock(&conn->lock);
+
+	wake_up(&conn->chanwait);
+
+	rxrpc_put_connection(conn);
+
+	/* clear the timers and dequeue from krxiod */
+	del_timer_sync(&call->acks_timeout);
+	del_timer_sync(&call->rcv_timeout);
+	del_timer_sync(&call->ackr_dfr_timo);
+
+	rxrpc_krxiod_dequeue_call(call);
+
+	/* clean up the contents of the struct */
+	if (call->snd_nextmsg)
+		rxrpc_put_message(call->snd_nextmsg);
+
+	if (call->snd_ping)
+		rxrpc_put_message(call->snd_ping);
+
+	while (!list_empty(&call->acks_pendq)) {
+		msg = list_entry(call->acks_pendq.next,
+				 struct rxrpc_message, link);
+		list_del(&msg->link);
+		rxrpc_put_message(msg);
+	}
+
+	while (!list_empty(&call->rcv_receiveq)) {
+		msg = list_entry(call->rcv_receiveq.next,
+				 struct rxrpc_message, link);
+		list_del(&msg->link);
+		rxrpc_put_message(msg);
+	}
+
+	while (!list_empty(&call->app_readyq)) {
+		msg = list_entry(call->app_readyq.next,
+				 struct rxrpc_message, link);
+		list_del(&msg->link);
+		rxrpc_put_message(msg);
+	}
+
+	while (!list_empty(&call->app_unreadyq)) {
+		msg = list_entry(call->app_unreadyq.next,
+				 struct rxrpc_message, link);
+		list_del(&msg->link);
+		rxrpc_put_message(msg);
+	}
+
+	module_put(call->owner);
+
+	down_write(&rxrpc_calls_sem);
+	list_del(&call->call_link);
+	up_write(&rxrpc_calls_sem);
+
+	__RXACCT(atomic_dec(&rxrpc_call_count));
+	free_page((unsigned long) call);
+
+	_leave(" [destroyed]");
+} /* end rxrpc_put_call() */
+
+/*****************************************************************************/
+/*
+ * actually generate a normal ACK
+ */
+static inline int __rxrpc_call_gen_normal_ACK(struct rxrpc_call *call,
+					      rxrpc_seq_t seq)
+{
+	struct rxrpc_message *msg;
+	struct kvec diov[3];
+	__be32 aux[4];
+	int delta, ret;
+
+	/* ACKs default to DELAY */
+	if (!call->ackr.reason)
+		call->ackr.reason = RXRPC_ACK_DELAY;
+
+	_proto("Rx %05lu Sending ACK { m=%hu f=#%u p=#%u s=%%%u r=%s n=%u }",
+	       jiffies - call->cjif,
+	       ntohs(call->ackr.maxSkew),
+	       ntohl(call->ackr.firstPacket),
+	       ntohl(call->ackr.previousPacket),
+	       ntohl(call->ackr.serial),
+	       rxrpc_acks[call->ackr.reason],
+	       call->ackr.nAcks);
+
+	aux[0] = htonl(call->conn->peer->if_mtu);	/* interface MTU */
+	aux[1] = htonl(1444);				/* max MTU */
+	aux[2] = htonl(16);				/* rwind */
+	aux[3] = htonl(4);				/* max packets */
+
+	diov[0].iov_len  = sizeof(struct rxrpc_ackpacket);
+	diov[0].iov_base = &call->ackr;
+	diov[1].iov_len  = call->ackr_pend_cnt + 3;
+	diov[1].iov_base = call->ackr_array;
+	diov[2].iov_len  = sizeof(aux);
+	diov[2].iov_base = &aux;
+
+	/* build and send the message */
+	ret = rxrpc_conn_newmsg(call->conn,call, RXRPC_PACKET_TYPE_ACK,
+				3, diov, GFP_KERNEL, &msg);
+	if (ret < 0)
+		goto out;
+
+	msg->seq = seq;
+	msg->hdr.seq = htonl(seq);
+	msg->hdr.flags |= RXRPC_SLOW_START_OK;
+
+	ret = rxrpc_conn_sendmsg(call->conn, msg);
+	rxrpc_put_message(msg);
+	if (ret < 0)
+		goto out;
+	call->pkt_snd_count++;
+
+	/* count how many actual ACKs there were at the front */
+	for (delta = 0; delta < call->ackr_pend_cnt; delta++)
+		if (call->ackr_array[delta] != RXRPC_ACK_TYPE_ACK)
+			break;
+
+	call->ackr_pend_cnt -= delta; /* all ACK'd to this point */
+
+	/* crank the ACK window around */
+	if (delta == 0) {
+		/* un-ACK'd window */
+	}
+	else if (delta < RXRPC_CALL_ACK_WINDOW_SIZE) {
+		/* partially ACK'd window
+		 * - shuffle down to avoid losing out-of-sequence packets
+		 */
+		call->ackr_win_bot += delta;
+		call->ackr_win_top += delta;
+
+		memmove(&call->ackr_array[0],
+			&call->ackr_array[delta],
+			call->ackr_pend_cnt);
+
+		memset(&call->ackr_array[call->ackr_pend_cnt],
+		       RXRPC_ACK_TYPE_NACK,
+		       sizeof(call->ackr_array) - call->ackr_pend_cnt);
+	}
+	else {
+		/* fully ACK'd window
+		 * - just clear the whole thing
+		 */
+		memset(&call->ackr_array,
+		       RXRPC_ACK_TYPE_NACK,
+		       sizeof(call->ackr_array));
+	}
+
+	/* clear this ACK */
+	memset(&call->ackr, 0, sizeof(call->ackr));
+
+ out:
+	if (!call->app_call_state)
+		printk("___ STATE 0 ___\n");
+	return ret;
+} /* end __rxrpc_call_gen_normal_ACK() */
+
+/*****************************************************************************/
+/*
+ * note the reception of a packet in the call's ACK records and generate an
+ * appropriate ACK packet if necessary
+ * - returns 0 if packet should be processed, 1 if packet should be ignored
+ *   and -ve on an error
+ */
+static int rxrpc_call_generate_ACK(struct rxrpc_call *call,
+				   struct rxrpc_header *hdr,
+				   struct rxrpc_ackpacket *ack)
+{
+	struct rxrpc_message *msg;
+	rxrpc_seq_t seq;
+	unsigned offset;
+	int ret = 0, err;
+	u8 special_ACK, do_ACK, force;
+
+	_enter("%p,%p { seq=%d tp=%d fl=%02x }",
+	       call, hdr, ntohl(hdr->seq), hdr->type, hdr->flags);
+
+	seq = ntohl(hdr->seq);
+	offset = seq - call->ackr_win_bot;
+	do_ACK = RXRPC_ACK_DELAY;
+	special_ACK = 0;
+	force = (seq == 1);
+
+	if (call->ackr_high_seq < seq)
+		call->ackr_high_seq = seq;
+
+	/* deal with generation of obvious special ACKs first */
+	if (ack && ack->reason == RXRPC_ACK_PING) {
+		special_ACK = RXRPC_ACK_PING_RESPONSE;
+		ret = 1;
+		goto gen_ACK;
+	}
+
+	if (seq < call->ackr_win_bot) {
+		special_ACK = RXRPC_ACK_DUPLICATE;
+		ret = 1;
+		goto gen_ACK;
+	}
+
+	if (seq >= call->ackr_win_top) {
+		special_ACK = RXRPC_ACK_EXCEEDS_WINDOW;
+		ret = 1;
+		goto gen_ACK;
+	}
+
+	if (call->ackr_array[offset] != RXRPC_ACK_TYPE_NACK) {
+		special_ACK = RXRPC_ACK_DUPLICATE;
+		ret = 1;
+		goto gen_ACK;
+	}
+
+	/* okay... it's a normal data packet inside the ACK window */
+	call->ackr_array[offset] = RXRPC_ACK_TYPE_ACK;
+
+	if (offset < call->ackr_pend_cnt) {
+	}
+	else if (offset > call->ackr_pend_cnt) {
+		do_ACK = RXRPC_ACK_OUT_OF_SEQUENCE;
+		call->ackr_pend_cnt = offset;
+		goto gen_ACK;
+	}
+
+	if (hdr->flags & RXRPC_REQUEST_ACK) {
+		do_ACK = RXRPC_ACK_REQUESTED;
+	}
+
+	/* generate an ACK on the final packet of a reply just received */
+	if (hdr->flags & RXRPC_LAST_PACKET) {
+		if (call->conn->out_clientflag)
+			force = 1;
+	}
+	else if (!(hdr->flags & RXRPC_MORE_PACKETS)) {
+		do_ACK = RXRPC_ACK_REQUESTED;
+	}
+
+	/* re-ACK packets previously received out-of-order */
+	for (offset++; offset < RXRPC_CALL_ACK_WINDOW_SIZE; offset++)
+		if (call->ackr_array[offset] != RXRPC_ACK_TYPE_ACK)
+			break;
+
+	call->ackr_pend_cnt = offset;
+
+	/* generate an ACK if we fill up the window */
+	if (call->ackr_pend_cnt >= RXRPC_CALL_ACK_WINDOW_SIZE)
+		force = 1;
+
+ gen_ACK:
+	_debug("%05lu ACKs pend=%u norm=%s special=%s%s",
+	       jiffies - call->cjif,
+	       call->ackr_pend_cnt,
+	       rxrpc_acks[do_ACK],
+	       rxrpc_acks[special_ACK],
+	       force ? " immediate" :
+	       do_ACK == RXRPC_ACK_REQUESTED ? " merge-req" :
+	       hdr->flags & RXRPC_LAST_PACKET ? " finalise" :
+	       " defer"
+	       );
+
+	/* send any pending normal ACKs if need be */
+	if (call->ackr_pend_cnt > 0) {
+		/* fill out the appropriate form */
+		call->ackr.bufferSpace	= htons(RXRPC_CALL_ACK_WINDOW_SIZE);
+		call->ackr.maxSkew	= htons(min(call->ackr_high_seq - seq,
+						    65535U));
+		call->ackr.firstPacket	= htonl(call->ackr_win_bot);
+		call->ackr.previousPacket = call->ackr_prev_seq;
+		call->ackr.serial	= hdr->serial;
+		call->ackr.nAcks	= call->ackr_pend_cnt;
+
+		if (do_ACK == RXRPC_ACK_REQUESTED)
+			call->ackr.reason = do_ACK;
+
+		/* generate the ACK immediately if necessary */
+		if (special_ACK || force) {
+			err = __rxrpc_call_gen_normal_ACK(
+				call, do_ACK == RXRPC_ACK_DELAY ? 0 : seq);
+			if (err < 0) {
+				ret = err;
+				goto out;
+			}
+		}
+	}
+
+	if (call->ackr.reason == RXRPC_ACK_REQUESTED)
+		call->ackr_dfr_seq = seq;
+
+	/* start the ACK timer if not running if there are any pending deferred
+	 * ACKs */
+	if (call->ackr_pend_cnt > 0 &&
+	    call->ackr.reason != RXRPC_ACK_REQUESTED &&
+	    !timer_pending(&call->ackr_dfr_timo)
+	    ) {
+		unsigned long timo;
+
+		timo = rxrpc_call_dfr_ack_timeout + jiffies;
+
+		_debug("START ACKR TIMER for cj=%lu", timo - call->cjif);
+
+		spin_lock(&call->lock);
+		mod_timer(&call->ackr_dfr_timo, timo);
+		spin_unlock(&call->lock);
+	}
+	else if ((call->ackr_pend_cnt == 0 ||
+		  call->ackr.reason == RXRPC_ACK_REQUESTED) &&
+		 timer_pending(&call->ackr_dfr_timo)
+		 ) {
+		/* stop timer if no pending ACKs */
+		_debug("CLEAR ACKR TIMER");
+		del_timer_sync(&call->ackr_dfr_timo);
+	}
+
+	/* send a special ACK if one is required */
+	if (special_ACK) {
+		struct rxrpc_ackpacket ack;
+		struct kvec diov[2];
+		uint8_t acks[1] = { RXRPC_ACK_TYPE_ACK };
+
+		/* fill out the appropriate form */
+		ack.bufferSpace	= htons(RXRPC_CALL_ACK_WINDOW_SIZE);
+		ack.maxSkew	= htons(min(call->ackr_high_seq - seq,
+					    65535U));
+		ack.firstPacket	= htonl(call->ackr_win_bot);
+		ack.previousPacket = call->ackr_prev_seq;
+		ack.serial	= hdr->serial;
+		ack.reason	= special_ACK;
+		ack.nAcks	= 0;
+
+		_proto("Rx Sending s-ACK"
+		       " { m=%hu f=#%u p=#%u s=%%%u r=%s n=%u }",
+		       ntohs(ack.maxSkew),
+		       ntohl(ack.firstPacket),
+		       ntohl(ack.previousPacket),
+		       ntohl(ack.serial),
+		       rxrpc_acks[ack.reason],
+		       ack.nAcks);
+
+		diov[0].iov_len  = sizeof(struct rxrpc_ackpacket);
+		diov[0].iov_base = &ack;
+		diov[1].iov_len  = sizeof(acks);
+		diov[1].iov_base = acks;
+
+		/* build and send the message */
+		err = rxrpc_conn_newmsg(call->conn,call, RXRPC_PACKET_TYPE_ACK,
+					hdr->seq ? 2 : 1, diov,
+					GFP_KERNEL,
+					&msg);
+		if (err < 0) {
+			ret = err;
+			goto out;
+		}
+
+		msg->seq = seq;
+		msg->hdr.seq = htonl(seq);
+		msg->hdr.flags |= RXRPC_SLOW_START_OK;
+
+		err = rxrpc_conn_sendmsg(call->conn, msg);
+		rxrpc_put_message(msg);
+		if (err < 0) {
+			ret = err;
+			goto out;
+		}
+		call->pkt_snd_count++;
+	}
+
+ out:
+	if (hdr->seq)
+		call->ackr_prev_seq = hdr->seq;
+
+	_leave(" = %d", ret);
+	return ret;
+} /* end rxrpc_call_generate_ACK() */
+
+/*****************************************************************************/
+/*
+ * handle work to be done on a call
+ * - includes packet reception and timeout processing
+ */
+void rxrpc_call_do_stuff(struct rxrpc_call *call)
+{
+	_enter("%p{flags=%lx}", call, call->flags);
+
+	/* handle packet reception */
+	if (call->flags & RXRPC_CALL_RCV_PKT) {
+		_debug("- receive packet");
+		call->flags &= ~RXRPC_CALL_RCV_PKT;
+		rxrpc_call_receive_packet(call);
+	}
+
+	/* handle overdue ACKs */
+	if (call->flags & RXRPC_CALL_ACKS_TIMO) {
+		_debug("- overdue ACK timeout");
+		call->flags &= ~RXRPC_CALL_ACKS_TIMO;
+		rxrpc_call_resend(call, call->snd_seq_count);
+	}
+
+	/* handle lack of reception */
+	if (call->flags & RXRPC_CALL_RCV_TIMO) {
+		_debug("- reception timeout");
+		call->flags &= ~RXRPC_CALL_RCV_TIMO;
+		rxrpc_call_abort(call, -EIO);
+	}
+
+	/* handle deferred ACKs */
+	if (call->flags & RXRPC_CALL_ACKR_TIMO ||
+	    (call->ackr.nAcks > 0 && call->ackr.reason == RXRPC_ACK_REQUESTED)
+	    ) {
+		_debug("- deferred ACK timeout: cj=%05lu r=%s n=%u",
+		       jiffies - call->cjif,
+		       rxrpc_acks[call->ackr.reason],
+		       call->ackr.nAcks);
+
+		call->flags &= ~RXRPC_CALL_ACKR_TIMO;
+
+		if (call->ackr.nAcks > 0 &&
+		    call->app_call_state != RXRPC_CSTATE_ERROR) {
+			/* generate ACK */
+			__rxrpc_call_gen_normal_ACK(call, call->ackr_dfr_seq);
+			call->ackr_dfr_seq = 0;
+		}
+	}
+
+	_leave("");
+
+} /* end rxrpc_call_do_stuff() */
+
+/*****************************************************************************/
+/*
+ * send an abort message at call or connection level
+ * - must be called with call->lock held
+ * - the supplied error code is sent as the packet data
+ */
+static int __rxrpc_call_abort(struct rxrpc_call *call, int errno)
+{
+	struct rxrpc_connection *conn = call->conn;
+	struct rxrpc_message *msg;
+	struct kvec diov[1];
+	int ret;
+	__be32 _error;
+
+	_enter("%p{%08x},%p{%d},%d",
+	       conn, ntohl(conn->conn_id), call, ntohl(call->call_id), errno);
+
+	/* if this call is already aborted, then just wake up any waiters */
+	if (call->app_call_state == RXRPC_CSTATE_ERROR) {
+		spin_unlock(&call->lock);
+		call->app_error_func(call);
+		_leave(" = 0");
+		return 0;
+	}
+
+	rxrpc_get_call(call);
+
+	/* change the state _with_ the lock still held */
+	call->app_call_state	= RXRPC_CSTATE_ERROR;
+	call->app_err_state	= RXRPC_ESTATE_LOCAL_ABORT;
+	call->app_errno		= errno;
+	call->app_mark		= RXRPC_APP_MARK_EOF;
+	call->app_read_buf	= NULL;
+	call->app_async_read	= 0;
+
+	_state(call);
+
+	/* ask the app to translate the error code */
+	call->app_aemap_func(call);
+
+	spin_unlock(&call->lock);
+
+	/* flush any outstanding ACKs */
+	del_timer_sync(&call->acks_timeout);
+	del_timer_sync(&call->rcv_timeout);
+	del_timer_sync(&call->ackr_dfr_timo);
+
+	if (rxrpc_call_is_ack_pending(call))
+		__rxrpc_call_gen_normal_ACK(call, 0);
+
+	/* send the abort packet only if we actually traded some other
+	 * packets */
+	ret = 0;
+	if (call->pkt_snd_count || call->pkt_rcv_count) {
+		/* actually send the abort */
+		_proto("Rx Sending Call ABORT { data=%d }",
+		       call->app_abort_code);
+
+		_error = htonl(call->app_abort_code);
+
+		diov[0].iov_len  = sizeof(_error);
+		diov[0].iov_base = &_error;
+
+		ret = rxrpc_conn_newmsg(conn, call, RXRPC_PACKET_TYPE_ABORT,
+					1, diov, GFP_KERNEL, &msg);
+		if (ret == 0) {
+			ret = rxrpc_conn_sendmsg(conn, msg);
+			rxrpc_put_message(msg);
+		}
+	}
+
+	/* tell the app layer to let go */
+	call->app_error_func(call);
+
+	rxrpc_put_call(call);
+
+	_leave(" = %d", ret);
+	return ret;
+} /* end __rxrpc_call_abort() */
+
+/*****************************************************************************/
+/*
+ * send an abort message at call or connection level
+ * - the supplied error code is sent as the packet data
+ */
+int rxrpc_call_abort(struct rxrpc_call *call, int error)
+{
+	spin_lock(&call->lock);
+
+	return __rxrpc_call_abort(call, error);
+
+} /* end rxrpc_call_abort() */
+
+/*****************************************************************************/
+/*
+ * process packets waiting for this call
+ */
+static void rxrpc_call_receive_packet(struct rxrpc_call *call)
+{
+	struct rxrpc_message *msg;
+	struct list_head *_p;
+
+	_enter("%p", call);
+
+	rxrpc_get_call(call); /* must not go away too soon if aborted by
+			       * app-layer */
+
+	while (!list_empty(&call->rcv_receiveq)) {
+		/* try to get next packet */
+		_p = NULL;
+		spin_lock(&call->lock);
+		if (!list_empty(&call->rcv_receiveq)) {
+			_p = call->rcv_receiveq.next;
+			list_del_init(_p);
+		}
+		spin_unlock(&call->lock);
+
+		if (!_p)
+			break;
+
+		msg = list_entry(_p, struct rxrpc_message, link);
+
+		_proto("Rx %05lu Received %s packet (%%%u,#%u,%c%c%c%c%c)",
+		       jiffies - call->cjif,
+		       rxrpc_pkts[msg->hdr.type],
+		       ntohl(msg->hdr.serial),
+		       msg->seq,
+		       msg->hdr.flags & RXRPC_JUMBO_PACKET	? 'j' : '-',
+		       msg->hdr.flags & RXRPC_MORE_PACKETS	? 'm' : '-',
+		       msg->hdr.flags & RXRPC_LAST_PACKET	? 'l' : '-',
+		       msg->hdr.flags & RXRPC_REQUEST_ACK	? 'r' : '-',
+		       msg->hdr.flags & RXRPC_CLIENT_INITIATED	? 'C' : 'S'
+		       );
+
+		switch (msg->hdr.type) {
+			/* deal with data packets */
+		case RXRPC_PACKET_TYPE_DATA:
+			/* ACK the packet if necessary */
+			switch (rxrpc_call_generate_ACK(call, &msg->hdr,
+							NULL)) {
+			case 0: /* useful packet */
+				rxrpc_call_receive_data_packet(call, msg);
+				break;
+			case 1: /* duplicate or out-of-window packet */
+				break;
+			default:
+				rxrpc_put_message(msg);
+				goto out;
+			}
+			break;
+
+			/* deal with ACK packets */
+		case RXRPC_PACKET_TYPE_ACK:
+			rxrpc_call_receive_ack_packet(call, msg);
+			break;
+
+			/* deal with abort packets */
+		case RXRPC_PACKET_TYPE_ABORT: {
+			__be32 _dbuf, *dp;
+
+			dp = skb_header_pointer(msg->pkt, msg->offset,
+						sizeof(_dbuf), &_dbuf);
+			if (dp == NULL)
+				printk("Rx Received short ABORT packet\n");
+
+			_proto("Rx Received Call ABORT { data=%d }",
+			       (dp ? ntohl(*dp) : 0));
+
+			spin_lock(&call->lock);
+			call->app_call_state	= RXRPC_CSTATE_ERROR;
+			call->app_err_state	= RXRPC_ESTATE_PEER_ABORT;
+			call->app_abort_code	= (dp ? ntohl(*dp) : 0);
+			call->app_errno		= -ECONNABORTED;
+			call->app_mark		= RXRPC_APP_MARK_EOF;
+			call->app_read_buf	= NULL;
+			call->app_async_read	= 0;
+
+			/* ask the app to translate the error code */
+			call->app_aemap_func(call);
+			_state(call);
+			spin_unlock(&call->lock);
+			call->app_error_func(call);
+			break;
+		}
+		default:
+			/* deal with other packet types */
+			_proto("Rx Unsupported packet type %u (#%u)",
+			       msg->hdr.type, msg->seq);
+			break;
+		}
+
+		rxrpc_put_message(msg);
+	}
+
+ out:
+	rxrpc_put_call(call);
+	_leave("");
+} /* end rxrpc_call_receive_packet() */
+
+/*****************************************************************************/
+/*
+ * process next data packet
+ * - as the next data packet arrives:
+ *   - it is queued on app_readyq _if_ it is the next one expected
+ *     (app_ready_seq+1)
+ *   - it is queued on app_unreadyq _if_ it is not the next one expected
+ *   - if a packet placed on app_readyq completely fills a hole leading up to
+ *     the first packet on app_unreadyq, then packets now in sequence are
+ *     tranferred to app_readyq
+ * - the application layer can only see packets on app_readyq
+ *   (app_ready_qty bytes)
+ * - the application layer is prodded every time a new packet arrives
+ */
+static void rxrpc_call_receive_data_packet(struct rxrpc_call *call,
+					   struct rxrpc_message *msg)
+{
+	const struct rxrpc_operation *optbl, *op;
+	struct rxrpc_message *pmsg;
+	struct list_head *_p;
+	int ret, lo, hi, rmtimo;
+	__be32 opid;
+
+	_enter("%p{%u},%p{%u}", call, ntohl(call->call_id), msg, msg->seq);
+
+	rxrpc_get_message(msg);
+
+	/* add to the unready queue if we'd have to create a hole in the ready
+	 * queue otherwise */
+	if (msg->seq != call->app_ready_seq + 1) {
+		_debug("Call add packet %d to unreadyq", msg->seq);
+
+		/* insert in seq order */
+		list_for_each(_p, &call->app_unreadyq) {
+			pmsg = list_entry(_p, struct rxrpc_message, link);
+			if (pmsg->seq > msg->seq)
+				break;
+		}
+
+		list_add_tail(&msg->link, _p);
+
+		_leave(" [unreadyq]");
+		return;
+	}
+
+	/* next in sequence - simply append into the call's ready queue */
+	_debug("Call add packet %d to readyq (+%Zd => %Zd bytes)",
+	       msg->seq, msg->dsize, call->app_ready_qty);
+
+	spin_lock(&call->lock);
+	call->app_ready_seq = msg->seq;
+	call->app_ready_qty += msg->dsize;
+	list_add_tail(&msg->link, &call->app_readyq);
+
+	/* move unready packets to the readyq if we got rid of a hole */
+	while (!list_empty(&call->app_unreadyq)) {
+		pmsg = list_entry(call->app_unreadyq.next,
+				  struct rxrpc_message, link);
+
+		if (pmsg->seq != call->app_ready_seq + 1)
+			break;
+
+		/* next in sequence - just move list-to-list */
+		_debug("Call transfer packet %d to readyq (+%Zd => %Zd bytes)",
+		       pmsg->seq, pmsg->dsize, call->app_ready_qty);
+
+		call->app_ready_seq = pmsg->seq;
+		call->app_ready_qty += pmsg->dsize;
+		list_del_init(&pmsg->link);
+		list_add_tail(&pmsg->link, &call->app_readyq);
+	}
+
+	/* see if we've got the last packet yet */
+	if (!list_empty(&call->app_readyq)) {
+		pmsg = list_entry(call->app_readyq.prev,
+				  struct rxrpc_message, link);
+		if (pmsg->hdr.flags & RXRPC_LAST_PACKET) {
+			call->app_last_rcv = 1;
+			_debug("Last packet on readyq");
+		}
+	}
+
+	switch (call->app_call_state) {
+		/* do nothing if call already aborted */
+	case RXRPC_CSTATE_ERROR:
+		spin_unlock(&call->lock);
+		_leave(" [error]");
+		return;
+
+		/* extract the operation ID from an incoming call if that's not
+		 * yet been done */
+	case RXRPC_CSTATE_SRVR_RCV_OPID:
+		spin_unlock(&call->lock);
+
+		/* handle as yet insufficient data for the operation ID */
+		if (call->app_ready_qty < 4) {
+			if (call->app_last_rcv)
+				/* trouble - last packet seen */
+				rxrpc_call_abort(call, -EINVAL);
+
+			_leave("");
+			return;
+		}
+
+		/* pull the operation ID out of the buffer */
+		ret = rxrpc_call_read_data(call, &opid, sizeof(opid), 0);
+		if (ret < 0) {
+			printk("Unexpected error from read-data: %d\n", ret);
+			if (call->app_call_state != RXRPC_CSTATE_ERROR)
+				rxrpc_call_abort(call, ret);
+			_leave("");
+			return;
+		}
+		call->app_opcode = ntohl(opid);
+
+		/* locate the operation in the available ops table */
+		optbl = call->conn->service->ops_begin;
+		lo = 0;
+		hi = call->conn->service->ops_end - optbl;
+
+		while (lo < hi) {
+			int mid = (hi + lo) / 2;
+			op = &optbl[mid];
+			if (call->app_opcode == op->id)
+				goto found_op;
+			if (call->app_opcode > op->id)
+				lo = mid + 1;
+			else
+				hi = mid;
+		}
+
+		/* search failed */
+		kproto("Rx Client requested operation %d from %s service",
+		       call->app_opcode, call->conn->service->name);
+		rxrpc_call_abort(call, -EINVAL);
+		_leave(" [inval]");
+		return;
+
+	found_op:
+		_proto("Rx Client requested operation %s from %s service",
+		       op->name, call->conn->service->name);
+
+		/* we're now waiting for the argument block (unless the call
+		 * was aborted) */
+		spin_lock(&call->lock);
+		if (call->app_call_state == RXRPC_CSTATE_SRVR_RCV_OPID ||
+		    call->app_call_state == RXRPC_CSTATE_SRVR_SND_REPLY) {
+			if (!call->app_last_rcv)
+				call->app_call_state =
+					RXRPC_CSTATE_SRVR_RCV_ARGS;
+			else if (call->app_ready_qty > 0)
+				call->app_call_state =
+					RXRPC_CSTATE_SRVR_GOT_ARGS;
+			else
+				call->app_call_state =
+					RXRPC_CSTATE_SRVR_SND_REPLY;
+			call->app_mark = op->asize;
+			call->app_user = op->user;
+		}
+		spin_unlock(&call->lock);
+
+		_state(call);
+		break;
+
+	case RXRPC_CSTATE_SRVR_RCV_ARGS:
+		/* change state if just received last packet of arg block */
+		if (call->app_last_rcv)
+			call->app_call_state = RXRPC_CSTATE_SRVR_GOT_ARGS;
+		spin_unlock(&call->lock);
+
+		_state(call);
+		break;
+
+	case RXRPC_CSTATE_CLNT_RCV_REPLY:
+		/* change state if just received last packet of reply block */
+		rmtimo = 0;
+		if (call->app_last_rcv) {
+			call->app_call_state = RXRPC_CSTATE_CLNT_GOT_REPLY;
+			rmtimo = 1;
+		}
+		spin_unlock(&call->lock);
+
+		if (rmtimo) {
+			del_timer_sync(&call->acks_timeout);
+			del_timer_sync(&call->rcv_timeout);
+			del_timer_sync(&call->ackr_dfr_timo);
+		}
+
+		_state(call);
+		break;
+
+	default:
+		/* deal with data reception in an unexpected state */
+		printk("Unexpected state [[[ %u ]]]\n", call->app_call_state);
+		__rxrpc_call_abort(call, -EBADMSG);
+		_leave("");
+		return;
+	}
+
+	if (call->app_call_state == RXRPC_CSTATE_CLNT_RCV_REPLY &&
+	    call->app_last_rcv)
+		BUG();
+
+	/* otherwise just invoke the data function whenever we can satisfy its desire for more
+	 * data
+	 */
+	_proto("Rx Received Op Data: st=%u qty=%Zu mk=%Zu%s",
+	       call->app_call_state, call->app_ready_qty, call->app_mark,
+	       call->app_last_rcv ? " last-rcvd" : "");
+
+	spin_lock(&call->lock);
+
+	ret = __rxrpc_call_read_data(call);
+	switch (ret) {
+	case 0:
+		spin_unlock(&call->lock);
+		call->app_attn_func(call);
+		break;
+	case -EAGAIN:
+		spin_unlock(&call->lock);
+		break;
+	case -ECONNABORTED:
+		spin_unlock(&call->lock);
+		break;
+	default:
+		__rxrpc_call_abort(call, ret);
+		break;
+	}
+
+	_state(call);
+
+	_leave("");
+
+} /* end rxrpc_call_receive_data_packet() */
+
+/*****************************************************************************/
+/*
+ * received an ACK packet
+ */
+static void rxrpc_call_receive_ack_packet(struct rxrpc_call *call,
+					  struct rxrpc_message *msg)
+{
+	struct rxrpc_ackpacket _ack, *ap;
+	rxrpc_serial_net_t serial;
+	rxrpc_seq_t seq;
+	int ret;
+
+	_enter("%p{%u},%p{%u}", call, ntohl(call->call_id), msg, msg->seq);
+
+	/* extract the basic ACK record */
+	ap = skb_header_pointer(msg->pkt, msg->offset, sizeof(_ack), &_ack);
+	if (ap == NULL) {
+		printk("Rx Received short ACK packet\n");
+		return;
+	}
+	msg->offset += sizeof(_ack);
+
+	serial = ap->serial;
+	seq = ntohl(ap->firstPacket);
+
+	_proto("Rx Received ACK %%%d { b=%hu m=%hu f=%u p=%u s=%u r=%s n=%u }",
+	       ntohl(msg->hdr.serial),
+	       ntohs(ap->bufferSpace),
+	       ntohs(ap->maxSkew),
+	       seq,
+	       ntohl(ap->previousPacket),
+	       ntohl(serial),
+	       rxrpc_acks[ap->reason],
+	       call->ackr.nAcks
+	       );
+
+	/* check the other side isn't ACK'ing a sequence number I haven't sent
+	 * yet */
+	if (ap->nAcks > 0 &&
+	    (seq > call->snd_seq_count ||
+	     seq + ap->nAcks - 1 > call->snd_seq_count)) {
+		printk("Received ACK (#%u-#%u) for unsent packet\n",
+		       seq, seq + ap->nAcks - 1);
+		rxrpc_call_abort(call, -EINVAL);
+		_leave("");
+		return;
+	}
+
+	/* deal with RTT calculation */
+	if (serial) {
+		struct rxrpc_message *rttmsg;
+
+		/* find the prompting packet */
+		spin_lock(&call->lock);
+		if (call->snd_ping && call->snd_ping->hdr.serial == serial) {
+			/* it was a ping packet */
+			rttmsg = call->snd_ping;
+			call->snd_ping = NULL;
+			spin_unlock(&call->lock);
+
+			if (rttmsg) {
+				rttmsg->rttdone = 1;
+				rxrpc_peer_calculate_rtt(call->conn->peer,
+							 rttmsg, msg);
+				rxrpc_put_message(rttmsg);
+			}
+		}
+		else {
+			struct list_head *_p;
+
+			/* it ought to be a data packet - look in the pending
+			 * ACK list */
+			list_for_each(_p, &call->acks_pendq) {
+				rttmsg = list_entry(_p, struct rxrpc_message,
+						    link);
+				if (rttmsg->hdr.serial == serial) {
+					if (rttmsg->rttdone)
+						/* never do RTT twice without
+						 * resending */
+						break;
+
+					rttmsg->rttdone = 1;
+					rxrpc_peer_calculate_rtt(
+						call->conn->peer, rttmsg, msg);
+					break;
+				}
+			}
+			spin_unlock(&call->lock);
+		}
+	}
+
+	switch (ap->reason) {
+		/* deal with negative/positive acknowledgement of data
+		 * packets */
+	case RXRPC_ACK_REQUESTED:
+	case RXRPC_ACK_DELAY:
+	case RXRPC_ACK_IDLE:
+		rxrpc_call_definitively_ACK(call, seq - 1);
+
+	case RXRPC_ACK_DUPLICATE:
+	case RXRPC_ACK_OUT_OF_SEQUENCE:
+	case RXRPC_ACK_EXCEEDS_WINDOW:
+		call->snd_resend_cnt = 0;
+		ret = rxrpc_call_record_ACK(call, msg, seq, ap->nAcks);
+		if (ret < 0)
+			rxrpc_call_abort(call, ret);
+		break;
+
+		/* respond to ping packets immediately */
+	case RXRPC_ACK_PING:
+		rxrpc_call_generate_ACK(call, &msg->hdr, ap);
+		break;
+
+		/* only record RTT on ping response packets */
+	case RXRPC_ACK_PING_RESPONSE:
+		if (call->snd_ping) {
+			struct rxrpc_message *rttmsg;
+
+			/* only do RTT stuff if the response matches the
+			 * retained ping */
+			rttmsg = NULL;
+			spin_lock(&call->lock);
+			if (call->snd_ping &&
+			    call->snd_ping->hdr.serial == ap->serial) {
+				rttmsg = call->snd_ping;
+				call->snd_ping = NULL;
+			}
+			spin_unlock(&call->lock);
+
+			if (rttmsg) {
+				rttmsg->rttdone = 1;
+				rxrpc_peer_calculate_rtt(call->conn->peer,
+							 rttmsg, msg);
+				rxrpc_put_message(rttmsg);
+			}
+		}
+		break;
+
+	default:
+		printk("Unsupported ACK reason %u\n", ap->reason);
+		break;
+	}
+
+	_leave("");
+} /* end rxrpc_call_receive_ack_packet() */
+
+/*****************************************************************************/
+/*
+ * record definitive ACKs for all messages up to and including the one with the
+ * 'highest' seq
+ */
+static void rxrpc_call_definitively_ACK(struct rxrpc_call *call,
+					rxrpc_seq_t highest)
+{
+	struct rxrpc_message *msg;
+	int now_complete;
+
+	_enter("%p{ads=%u},%u", call, call->acks_dftv_seq, highest);
+
+	while (call->acks_dftv_seq < highest) {
+		call->acks_dftv_seq++;
+
+		_proto("Definitive ACK on packet #%u", call->acks_dftv_seq);
+
+		/* discard those at front of queue until message with highest
+		 * ACK is found */
+		spin_lock(&call->lock);
+		msg = NULL;
+		if (!list_empty(&call->acks_pendq)) {
+			msg = list_entry(call->acks_pendq.next,
+					 struct rxrpc_message, link);
+			list_del_init(&msg->link); /* dequeue */
+			if (msg->state == RXRPC_MSG_SENT)
+				call->acks_pend_cnt--;
+		}
+		spin_unlock(&call->lock);
+
+		/* insanity check */
+		if (!msg)
+			panic("%s(): acks_pendq unexpectedly empty\n",
+			      __FUNCTION__);
+
+		if (msg->seq != call->acks_dftv_seq)
+			panic("%s(): Packet #%u expected at front of acks_pendq"
+			      " (#%u found)\n",
+			      __FUNCTION__, call->acks_dftv_seq, msg->seq);
+
+		/* discard the message */
+		msg->state = RXRPC_MSG_DONE;
+		rxrpc_put_message(msg);
+	}
+
+	/* if all sent packets are definitively ACK'd then prod any sleepers just in case */
+	now_complete = 0;
+	spin_lock(&call->lock);
+	if (call->acks_dftv_seq == call->snd_seq_count) {
+		if (call->app_call_state != RXRPC_CSTATE_COMPLETE) {
+			call->app_call_state = RXRPC_CSTATE_COMPLETE;
+			_state(call);
+			now_complete = 1;
+		}
+	}
+	spin_unlock(&call->lock);
+
+	if (now_complete) {
+		del_timer_sync(&call->acks_timeout);
+		del_timer_sync(&call->rcv_timeout);
+		del_timer_sync(&call->ackr_dfr_timo);
+		call->app_attn_func(call);
+	}
+
+	_leave("");
+} /* end rxrpc_call_definitively_ACK() */
+
+/*****************************************************************************/
+/*
+ * record the specified amount of ACKs/NAKs
+ */
+static int rxrpc_call_record_ACK(struct rxrpc_call *call,
+				 struct rxrpc_message *msg,
+				 rxrpc_seq_t seq,
+				 size_t count)
+{
+	struct rxrpc_message *dmsg;
+	struct list_head *_p;
+	rxrpc_seq_t highest;
+	unsigned ix;
+	size_t chunk;
+	char resend, now_complete;
+	u8 acks[16];
+
+	_enter("%p{apc=%u ads=%u},%p,%u,%Zu",
+	       call, call->acks_pend_cnt, call->acks_dftv_seq,
+	       msg, seq, count);
+
+	/* handle re-ACK'ing of definitively ACK'd packets (may be out-of-order
+	 * ACKs) */
+	if (seq <= call->acks_dftv_seq) {
+		unsigned delta = call->acks_dftv_seq - seq;
+
+		if (count <= delta) {
+			_leave(" = 0 [all definitively ACK'd]");
+			return 0;
+		}
+
+		seq += delta;
+		count -= delta;
+		msg->offset += delta;
+	}
+
+	highest = seq + count - 1;
+	resend = 0;
+	while (count > 0) {
+		/* extract up to 16 ACK slots at a time */
+		chunk = min(count, sizeof(acks));
+		count -= chunk;
+
+		memset(acks, 2, sizeof(acks));
+
+		if (skb_copy_bits(msg->pkt, msg->offset, &acks, chunk) < 0) {
+			printk("Rx Received short ACK packet\n");
+			_leave(" = -EINVAL");
+			return -EINVAL;
+		}
+		msg->offset += chunk;
+
+		/* check that the ACK set is valid */
+		for (ix = 0; ix < chunk; ix++) {
+			switch (acks[ix]) {
+			case RXRPC_ACK_TYPE_ACK:
+				break;
+			case RXRPC_ACK_TYPE_NACK:
+				resend = 1;
+				break;
+			default:
+				printk("Rx Received unsupported ACK state"
+				       " %u\n", acks[ix]);
+				_leave(" = -EINVAL");
+				return -EINVAL;
+			}
+		}
+
+		_proto("Rx ACK of packets #%u-#%u "
+		       "[%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c%c] (pend=%u)",
+		       seq, (unsigned) (seq + chunk - 1),
+		       _acktype[acks[0x0]],
+		       _acktype[acks[0x1]],
+		       _acktype[acks[0x2]],
+		       _acktype[acks[0x3]],
+		       _acktype[acks[0x4]],
+		       _acktype[acks[0x5]],
+		       _acktype[acks[0x6]],
+		       _acktype[acks[0x7]],
+		       _acktype[acks[0x8]],
+		       _acktype[acks[0x9]],
+		       _acktype[acks[0xA]],
+		       _acktype[acks[0xB]],
+		       _acktype[acks[0xC]],
+		       _acktype[acks[0xD]],
+		       _acktype[acks[0xE]],
+		       _acktype[acks[0xF]],
+		       call->acks_pend_cnt
+		       );
+
+		/* mark the packets in the ACK queue as being provisionally
+		 * ACK'd */
+		ix = 0;
+		spin_lock(&call->lock);
+
+		/* find the first packet ACK'd/NAK'd here */
+		list_for_each(_p, &call->acks_pendq) {
+			dmsg = list_entry(_p, struct rxrpc_message, link);
+			if (dmsg->seq == seq)
+				goto found_first;
+			_debug("- %u: skipping #%u", ix, dmsg->seq);
+		}
+		goto bad_queue;
+
+	found_first:
+		do {
+			_debug("- %u: processing #%u (%c) apc=%u",
+			       ix, dmsg->seq, _acktype[acks[ix]],
+			       call->acks_pend_cnt);
+
+			if (acks[ix] == RXRPC_ACK_TYPE_ACK) {
+				if (dmsg->state == RXRPC_MSG_SENT)
+					call->acks_pend_cnt--;
+				dmsg->state = RXRPC_MSG_ACKED;
+			}
+			else {
+				if (dmsg->state == RXRPC_MSG_ACKED)
+					call->acks_pend_cnt++;
+				dmsg->state = RXRPC_MSG_SENT;
+			}
+			ix++;
+			seq++;
+
+			_p = dmsg->link.next;
+			dmsg = list_entry(_p, struct rxrpc_message, link);
+		} while(ix < chunk &&
+			_p != &call->acks_pendq &&
+			dmsg->seq == seq);
+
+		if (ix < chunk)
+			goto bad_queue;
+
+		spin_unlock(&call->lock);
+	}
+
+	if (resend)
+		rxrpc_call_resend(call, highest);
+
+	/* if all packets are provisionally ACK'd, then wake up anyone who's
+	 * waiting for that */
+	now_complete = 0;
+	spin_lock(&call->lock);
+	if (call->acks_pend_cnt == 0) {
+		if (call->app_call_state == RXRPC_CSTATE_SRVR_RCV_FINAL_ACK) {
+			call->app_call_state = RXRPC_CSTATE_COMPLETE;
+			_state(call);
+		}
+		now_complete = 1;
+	}
+	spin_unlock(&call->lock);
+
+	if (now_complete) {
+		_debug("- wake up waiters");
+		del_timer_sync(&call->acks_timeout);
+		del_timer_sync(&call->rcv_timeout);
+		del_timer_sync(&call->ackr_dfr_timo);
+		call->app_attn_func(call);
+	}
+
+	_leave(" = 0 (apc=%u)", call->acks_pend_cnt);
+	return 0;
+
+ bad_queue:
+	panic("%s(): acks_pendq in bad state (packet #%u absent)\n",
+	      __FUNCTION__, seq);
+
+} /* end rxrpc_call_record_ACK() */
+
+/*****************************************************************************/
+/*
+ * transfer data from the ready packet queue to the asynchronous read buffer
+ * - since this func is the only one going to look at packets queued on
+ *   app_readyq, we don't need a lock to modify or access them, only to modify
+ *   the queue pointers
+ * - called with call->lock held
+ * - the buffer must be in kernel space
+ * - returns:
+ *	0 if buffer filled
+ *	-EAGAIN if buffer not filled and more data to come
+ *	-EBADMSG if last packet received and insufficient data left
+ *	-ECONNABORTED if the call has in an error state
+ */
+static int __rxrpc_call_read_data(struct rxrpc_call *call)
+{
+	struct rxrpc_message *msg;
+	size_t qty;
+	int ret;
+
+	_enter("%p{as=%d buf=%p qty=%Zu/%Zu}",
+	       call,
+	       call->app_async_read, call->app_read_buf,
+	       call->app_ready_qty, call->app_mark);
+
+	/* check the state */
+	switch (call->app_call_state) {
+	case RXRPC_CSTATE_SRVR_RCV_ARGS:
+	case RXRPC_CSTATE_CLNT_RCV_REPLY:
+		if (call->app_last_rcv) {
+			printk("%s(%p,%p,%Zd):"
+			       " Inconsistent call state (%s, last pkt)",
+			       __FUNCTION__,
+			       call, call->app_read_buf, call->app_mark,
+			       rxrpc_call_states[call->app_call_state]);
+			BUG();
+		}
+		break;
+
+	case RXRPC_CSTATE_SRVR_RCV_OPID:
+	case RXRPC_CSTATE_SRVR_GOT_ARGS:
+	case RXRPC_CSTATE_CLNT_GOT_REPLY:
+		break;
+
+	case RXRPC_CSTATE_SRVR_SND_REPLY:
+		if (!call->app_last_rcv) {
+			printk("%s(%p,%p,%Zd):"
+			       " Inconsistent call state (%s, not last pkt)",
+			       __FUNCTION__,
+			       call, call->app_read_buf, call->app_mark,
+			       rxrpc_call_states[call->app_call_state]);
+			BUG();
+		}
+		_debug("Trying to read data from call in SND_REPLY state");
+		break;
+
+	case RXRPC_CSTATE_ERROR:
+		_leave(" = -ECONNABORTED");
+		return -ECONNABORTED;
+
+	default:
+		printk("reading in unexpected state [[[ %u ]]]\n",
+		       call->app_call_state);
+		BUG();
+	}
+
+	/* handle the case of not having an async buffer */
+	if (!call->app_async_read) {
+		if (call->app_mark == RXRPC_APP_MARK_EOF) {
+			ret = call->app_last_rcv ? 0 : -EAGAIN;
+		}
+		else {
+			if (call->app_mark >= call->app_ready_qty) {
+				call->app_mark = RXRPC_APP_MARK_EOF;
+				ret = 0;
+			}
+			else {
+				ret = call->app_last_rcv ? -EBADMSG : -EAGAIN;
+			}
+		}
+
+		_leave(" = %d [no buf]", ret);
+		return 0;
+	}
+
+	while (!list_empty(&call->app_readyq) && call->app_mark > 0) {
+		msg = list_entry(call->app_readyq.next,
+				 struct rxrpc_message, link);
+
+		/* drag as much data as we need out of this packet */
+		qty = min(call->app_mark, msg->dsize);
+
+		_debug("reading %Zu from skb=%p off=%lu",
+		       qty, msg->pkt, msg->offset);
+
+		if (call->app_read_buf)
+			if (skb_copy_bits(msg->pkt, msg->offset,
+					  call->app_read_buf, qty) < 0)
+				panic("%s: Failed to copy data from packet:"
+				      " (%p,%p,%Zd)",
+				      __FUNCTION__,
+				      call, call->app_read_buf, qty);
+
+		/* if that packet is now empty, discard it */
+		call->app_ready_qty -= qty;
+		msg->dsize -= qty;
+
+		if (msg->dsize == 0) {
+			list_del_init(&msg->link);
+			rxrpc_put_message(msg);
+		}
+		else {
+			msg->offset += qty;
+		}
+
+		call->app_mark -= qty;
+		if (call->app_read_buf)
+			call->app_read_buf += qty;
+	}
+
+	if (call->app_mark == 0) {
+		call->app_async_read = 0;
+		call->app_mark = RXRPC_APP_MARK_EOF;
+		call->app_read_buf = NULL;
+
+		/* adjust the state if used up all packets */
+		if (list_empty(&call->app_readyq) && call->app_last_rcv) {
+			switch (call->app_call_state) {
+			case RXRPC_CSTATE_SRVR_RCV_OPID:
+				call->app_call_state = RXRPC_CSTATE_SRVR_SND_REPLY;
+				call->app_mark = RXRPC_APP_MARK_EOF;
+				_state(call);
+				del_timer_sync(&call->rcv_timeout);
+				break;
+			case RXRPC_CSTATE_SRVR_GOT_ARGS:
+				call->app_call_state = RXRPC_CSTATE_SRVR_SND_REPLY;
+				_state(call);
+				del_timer_sync(&call->rcv_timeout);
+				break;
+			default:
+				call->app_call_state = RXRPC_CSTATE_COMPLETE;
+				_state(call);
+				del_timer_sync(&call->acks_timeout);
+				del_timer_sync(&call->ackr_dfr_timo);
+				del_timer_sync(&call->rcv_timeout);
+				break;
+			}
+		}
+
+		_leave(" = 0");
+		return 0;
+	}
+
+	if (call->app_last_rcv) {
+		_debug("Insufficient data (%Zu/%Zu)",
+		       call->app_ready_qty, call->app_mark);
+		call->app_async_read = 0;
+		call->app_mark = RXRPC_APP_MARK_EOF;
+		call->app_read_buf = NULL;
+
+		_leave(" = -EBADMSG");
+		return -EBADMSG;
+	}
+
+	_leave(" = -EAGAIN");
+	return -EAGAIN;
+} /* end __rxrpc_call_read_data() */
+
+/*****************************************************************************/
+/*
+ * attempt to read the specified amount of data from the call's ready queue
+ * into the buffer provided
+ * - since this func is the only one going to look at packets queued on
+ *   app_readyq, we don't need a lock to modify or access them, only to modify
+ *   the queue pointers
+ * - if the buffer pointer is NULL, then data is merely drained, not copied
+ * - if flags&RXRPC_CALL_READ_BLOCK, then the function will wait until there is
+ *   enough data or an error will be generated
+ *   - note that the caller must have added the calling task to the call's wait
+ *     queue beforehand
+ * - if flags&RXRPC_CALL_READ_ALL, then an error will be generated if this
+ *   function doesn't read all available data
+ */
+int rxrpc_call_read_data(struct rxrpc_call *call,
+			 void *buffer, size_t size, int flags)
+{
+	int ret;
+
+	_enter("%p{arq=%Zu},%p,%Zd,%x",
+	       call, call->app_ready_qty, buffer, size, flags);
+
+	spin_lock(&call->lock);
+
+	if (unlikely(!!call->app_read_buf)) {
+		spin_unlock(&call->lock);
+		_leave(" = -EBUSY");
+		return -EBUSY;
+	}
+
+	call->app_mark = size;
+	call->app_read_buf = buffer;
+	call->app_async_read = 1;
+	call->app_read_count++;
+
+	/* read as much data as possible */
+	ret = __rxrpc_call_read_data(call);
+	switch (ret) {
+	case 0:
+		if (flags & RXRPC_CALL_READ_ALL &&
+		    (!call->app_last_rcv || call->app_ready_qty > 0)) {
+			_leave(" = -EBADMSG");
+			__rxrpc_call_abort(call, -EBADMSG);
+			return -EBADMSG;
+		}
+
+		spin_unlock(&call->lock);
+		call->app_attn_func(call);
+		_leave(" = 0");
+		return ret;
+
+	case -ECONNABORTED:
+		spin_unlock(&call->lock);
+		_leave(" = %d [aborted]", ret);
+		return ret;
+
+	default:
+		__rxrpc_call_abort(call, ret);
+		_leave(" = %d", ret);
+		return ret;
+
+	case -EAGAIN:
+		spin_unlock(&call->lock);
+
+		if (!(flags & RXRPC_CALL_READ_BLOCK)) {
+			_leave(" = -EAGAIN");
+			return -EAGAIN;
+		}
+
+		/* wait for the data to arrive */
+		_debug("blocking for data arrival");
+
+		for (;;) {
+			set_current_state(TASK_INTERRUPTIBLE);
+			if (!call->app_async_read || signal_pending(current))
+				break;
+			schedule();
+		}
+		set_current_state(TASK_RUNNING);
+
+		if (signal_pending(current)) {
+			_leave(" = -EINTR");
+			return -EINTR;
+		}
+
+		if (call->app_call_state == RXRPC_CSTATE_ERROR) {
+			_leave(" = -ECONNABORTED");
+			return -ECONNABORTED;
+		}
+
+		_leave(" = 0");
+		return 0;
+	}
+
+} /* end rxrpc_call_read_data() */
+
+/*****************************************************************************/
+/*
+ * write data to a call
+ * - the data may not be sent immediately if it doesn't fill a buffer
+ * - if we can't queue all the data for buffering now, siov[] will have been
+ *   adjusted to take account of what has been sent
+ */
+int rxrpc_call_write_data(struct rxrpc_call *call,
+			  size_t sioc,
+			  struct kvec *siov,
+			  u8 rxhdr_flags,
+			  int alloc_flags,
+			  int dup_data,
+			  size_t *size_sent)
+{
+	struct rxrpc_message *msg;
+	struct kvec *sptr;
+	size_t space, size, chunk, tmp;
+	char *buf;
+	int ret;
+
+	_enter("%p,%Zu,%p,%02x,%x,%d,%p",
+	       call, sioc, siov, rxhdr_flags, alloc_flags, dup_data,
+	       size_sent);
+
+	*size_sent = 0;
+	size = 0;
+	ret = -EINVAL;
+
+	/* can't send more if we've sent last packet from this end */
+	switch (call->app_call_state) {
+	case RXRPC_CSTATE_SRVR_SND_REPLY:
+	case RXRPC_CSTATE_CLNT_SND_ARGS:
+		break;
+	case RXRPC_CSTATE_ERROR:
+		ret = call->app_errno;
+	default:
+		goto out;
+	}
+
+	/* calculate how much data we've been given */
+	sptr = siov;
+	for (; sioc > 0; sptr++, sioc--) {
+		if (!sptr->iov_len)
+			continue;
+
+		if (!sptr->iov_base)
+			goto out;
+
+		size += sptr->iov_len;
+	}
+
+	_debug("- size=%Zu mtu=%Zu", size, call->conn->mtu_size);
+
+	do {
+		/* make sure there's a message under construction */
+		if (!call->snd_nextmsg) {
+			/* no - allocate a message with no data yet attached */
+			ret = rxrpc_conn_newmsg(call->conn, call,
+						RXRPC_PACKET_TYPE_DATA,
+						0, NULL, alloc_flags,
+						&call->snd_nextmsg);
+			if (ret < 0)
+				goto out;
+			_debug("- allocated new message [ds=%Zu]",
+			       call->snd_nextmsg->dsize);
+		}
+
+		msg = call->snd_nextmsg;
+		msg->hdr.flags |= rxhdr_flags;
+
+		/* deal with zero-length terminal packet */
+		if (size == 0) {
+			if (rxhdr_flags & RXRPC_LAST_PACKET) {
+				ret = rxrpc_call_flush(call);
+				if (ret < 0)
+					goto out;
+			}
+			break;
+		}
+
+		/* work out how much space current packet has available */
+		space = call->conn->mtu_size - msg->dsize;
+		chunk = min(space, size);
+
+		_debug("- [before] space=%Zu chunk=%Zu", space, chunk);
+
+		while (!siov->iov_len)
+			siov++;
+
+		/* if we are going to have to duplicate the data then coalesce
+		 * it too */
+		if (dup_data) {
+			/* don't allocate more that 1 page at a time */
+			if (chunk > PAGE_SIZE)
+				chunk = PAGE_SIZE;
+
+			/* allocate a data buffer and attach to the message */
+			buf = kmalloc(chunk, alloc_flags);
+			if (unlikely(!buf)) {
+				if (msg->dsize ==
+				    sizeof(struct rxrpc_header)) {
+					/* discard an empty msg and wind back
+					 * the seq counter */
+					rxrpc_put_message(msg);
+					call->snd_nextmsg = NULL;
+					call->snd_seq_count--;
+				}
+
+				ret = -ENOMEM;
+				goto out;
+			}
+
+			tmp = msg->dcount++;
+			set_bit(tmp, &msg->dfree);
+			msg->data[tmp].iov_base = buf;
+			msg->data[tmp].iov_len = chunk;
+			msg->dsize += chunk;
+			*size_sent += chunk;
+			size -= chunk;
+
+			/* load the buffer with data */
+			while (chunk > 0) {
+				tmp = min(chunk, siov->iov_len);
+				memcpy(buf, siov->iov_base, tmp);
+				buf += tmp;
+				siov->iov_base += tmp;
+				siov->iov_len -= tmp;
+				if (!siov->iov_len)
+					siov++;
+				chunk -= tmp;
+			}
+		}
+		else {
+			/* we want to attach the supplied buffers directly */
+			while (chunk > 0 &&
+			       msg->dcount < RXRPC_MSG_MAX_IOCS) {
+				tmp = msg->dcount++;
+				msg->data[tmp].iov_base = siov->iov_base;
+				msg->data[tmp].iov_len = siov->iov_len;
+				msg->dsize += siov->iov_len;
+				*size_sent += siov->iov_len;
+				size -= siov->iov_len;
+				chunk -= siov->iov_len;
+				siov++;
+			}
+		}
+
+		_debug("- [loaded] chunk=%Zu size=%Zu", chunk, size);
+
+		/* dispatch the message when full, final or requesting ACK */
+		if (msg->dsize >= call->conn->mtu_size || rxhdr_flags) {
+			ret = rxrpc_call_flush(call);
+			if (ret < 0)
+				goto out;
+		}
+
+	} while(size > 0);
+
+	ret = 0;
+ out:
+	_leave(" = %d (%Zd queued, %Zd rem)", ret, *size_sent, size);
+	return ret;
+
+} /* end rxrpc_call_write_data() */
+
+/*****************************************************************************/
+/*
+ * flush outstanding packets to the network
+ */
+static int rxrpc_call_flush(struct rxrpc_call *call)
+{
+	struct rxrpc_message *msg;
+	int ret = 0;
+
+	_enter("%p", call);
+
+	rxrpc_get_call(call);
+
+	/* if there's a packet under construction, then dispatch it now */
+	if (call->snd_nextmsg) {
+		msg = call->snd_nextmsg;
+		call->snd_nextmsg = NULL;
+
+		if (msg->hdr.flags & RXRPC_LAST_PACKET) {
+			msg->hdr.flags &= ~RXRPC_MORE_PACKETS;
+			if (call->app_call_state != RXRPC_CSTATE_CLNT_SND_ARGS)
+				msg->hdr.flags |= RXRPC_REQUEST_ACK;
+		}
+		else {
+			msg->hdr.flags |= RXRPC_MORE_PACKETS;
+		}
+
+		_proto("Sending DATA message { ds=%Zu dc=%u df=%02lu }",
+		       msg->dsize, msg->dcount, msg->dfree);
+
+		/* queue and adjust call state */
+		spin_lock(&call->lock);
+		list_add_tail(&msg->link, &call->acks_pendq);
+
+		/* decide what to do depending on current state and if this is
+		 * the last packet */
+		ret = -EINVAL;
+		switch (call->app_call_state) {
+		case RXRPC_CSTATE_SRVR_SND_REPLY:
+			if (msg->hdr.flags & RXRPC_LAST_PACKET) {
+				call->app_call_state =
+					RXRPC_CSTATE_SRVR_RCV_FINAL_ACK;
+				_state(call);
+			}
+			break;
+
+		case RXRPC_CSTATE_CLNT_SND_ARGS:
+			if (msg->hdr.flags & RXRPC_LAST_PACKET) {
+				call->app_call_state =
+					RXRPC_CSTATE_CLNT_RCV_REPLY;
+				_state(call);
+			}
+			break;
+
+		case RXRPC_CSTATE_ERROR:
+			ret = call->app_errno;
+		default:
+			spin_unlock(&call->lock);
+			goto out;
+		}
+
+		call->acks_pend_cnt++;
+
+		mod_timer(&call->acks_timeout,
+			  __rxrpc_rtt_based_timeout(call,
+						    rxrpc_call_acks_timeout));
+
+		spin_unlock(&call->lock);
+
+		ret = rxrpc_conn_sendmsg(call->conn, msg);
+		if (ret == 0)
+			call->pkt_snd_count++;
+	}
+
+ out:
+	rxrpc_put_call(call);
+
+	_leave(" = %d", ret);
+	return ret;
+
+} /* end rxrpc_call_flush() */
+
+/*****************************************************************************/
+/*
+ * resend NAK'd or unacknowledged packets up to the highest one specified
+ */
+static void rxrpc_call_resend(struct rxrpc_call *call, rxrpc_seq_t highest)
+{
+	struct rxrpc_message *msg;
+	struct list_head *_p;
+	rxrpc_seq_t seq = 0;
+
+	_enter("%p,%u", call, highest);
+
+	_proto("Rx Resend required");
+
+	/* handle too many resends */
+	if (call->snd_resend_cnt >= rxrpc_call_max_resend) {
+		_debug("Aborting due to too many resends (rcv=%d)",
+		       call->pkt_rcv_count);
+		rxrpc_call_abort(call,
+				 call->pkt_rcv_count > 0 ? -EIO : -ETIMEDOUT);
+		_leave("");
+		return;
+	}
+
+	spin_lock(&call->lock);
+	call->snd_resend_cnt++;
+	for (;;) {
+		/* determine which the next packet we might need to ACK is */
+		if (seq <= call->acks_dftv_seq)
+			seq = call->acks_dftv_seq;
+		seq++;
+
+		if (seq > highest)
+			break;
+
+		/* look for the packet in the pending-ACK queue */
+		list_for_each(_p, &call->acks_pendq) {
+			msg = list_entry(_p, struct rxrpc_message, link);
+			if (msg->seq == seq)
+				goto found_msg;
+		}
+
+		panic("%s(%p,%d):"
+		      " Inconsistent pending-ACK queue (ds=%u sc=%u sq=%u)\n",
+		      __FUNCTION__, call, highest,
+		      call->acks_dftv_seq, call->snd_seq_count, seq);
+
+	found_msg:
+		if (msg->state != RXRPC_MSG_SENT)
+			continue; /* only un-ACK'd packets */
+
+		rxrpc_get_message(msg);
+		spin_unlock(&call->lock);
+
+		/* send each message again (and ignore any errors we might
+		 * incur) */
+		_proto("Resending DATA message { ds=%Zu dc=%u df=%02lu }",
+		       msg->dsize, msg->dcount, msg->dfree);
+
+		if (rxrpc_conn_sendmsg(call->conn, msg) == 0)
+			call->pkt_snd_count++;
+
+		rxrpc_put_message(msg);
+
+		spin_lock(&call->lock);
+	}
+
+	/* reset the timeout */
+	mod_timer(&call->acks_timeout,
+		  __rxrpc_rtt_based_timeout(call, rxrpc_call_acks_timeout));
+
+	spin_unlock(&call->lock);
+
+	_leave("");
+} /* end rxrpc_call_resend() */
+
+/*****************************************************************************/
+/*
+ * handle an ICMP error being applied to a call
+ */
+void rxrpc_call_handle_error(struct rxrpc_call *call, int local, int errno)
+{
+	_enter("%p{%u},%d", call, ntohl(call->call_id), errno);
+
+	/* if this call is already aborted, then just wake up any waiters */
+	if (call->app_call_state == RXRPC_CSTATE_ERROR) {
+		call->app_error_func(call);
+	}
+	else {
+		/* tell the app layer what happened */
+		spin_lock(&call->lock);
+		call->app_call_state = RXRPC_CSTATE_ERROR;
+		_state(call);
+		if (local)
+			call->app_err_state = RXRPC_ESTATE_LOCAL_ERROR;
+		else
+			call->app_err_state = RXRPC_ESTATE_REMOTE_ERROR;
+		call->app_errno		= errno;
+		call->app_mark		= RXRPC_APP_MARK_EOF;
+		call->app_read_buf	= NULL;
+		call->app_async_read	= 0;
+
+		/* map the error */
+		call->app_aemap_func(call);
+
+		del_timer_sync(&call->acks_timeout);
+		del_timer_sync(&call->rcv_timeout);
+		del_timer_sync(&call->ackr_dfr_timo);
+
+		spin_unlock(&call->lock);
+
+		call->app_error_func(call);
+	}
+
+	_leave("");
+} /* end rxrpc_call_handle_error() */