rxrpc: Rename files matching ar-*.c to git rid of the "ar-" prefix

Rename files matching net/rxrpc/ar-*.c to get rid of the "ar-" prefix.
This will aid splitting those files by making easier to come up with new
names.

Note that the not all files are simply renamed from ar-X.c to X.c.  The
following exceptions are made:

 (*) ar-call.c -> call_object.c
     ar-ack.c -> call_event.c

     call_object.c is going to contain the core of the call object
     handling.  Call event handling is all going to be in call_event.c.

 (*) ar-accept.c -> call_accept.c

     Incoming call handling is going to be here.

 (*) ar-connection.c -> conn_object.c
     ar-connevent.c -> conn_event.c

     The former file is going to have the basic connection object handling,
     but there will likely be some differentiation between client
     connections and service connections in additional files later.  The
     latter file will have all the connection-level event handling.

 (*) ar-local.c -> local_object.c

     This will have the local endpoint object handling code.  The local
     endpoint event handling code will later be split out into
     local_event.c.

 (*) ar-peer.c -> peer_object.c

     This will have the peer endpoint object handling code.  Peer event
     handling code will be placed in peer_event.c (for the moment, there is
     none).

 (*) ar-error.c -> peer_event.c

     This will become the peer event handling code, though for the moment
     it's actually driven from the local endpoint's perspective.

Note that I haven't renamed ar-transport.c to transport_object.c as the
intention is to delete it when the rxrpc_transport struct is excised.

The only file that actually has its contents changed is net/rxrpc/Makefile.

net/rxrpc/ar-internal.h will need its section marker comments updating, but
I'll do that in a separate patch to make it easier for git to follow the
history across the rename.  I may also want to rename ar-internal.h at some
point - but that would mean updating all the #includes and I'd rather do
that in a separate step.

Signed-off-by: David Howells <dhowells@redhat.com.

1 files changed, 724 insertions, 0 deletions

diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
new file mode 100644
index 000000000000..2e3c4064e29c
--- /dev/null
+++ b/net/rxrpc/output.c
@@ -0,0 +1,724 @@
+/* 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/circ_buf.h>
+#include <linux/export.h>
+#include <net/sock.h>
+#include <net/af_rxrpc.h>
+#include "ar-internal.h"
+
+/*
+ * Time till packet resend (in jiffies).
+ */
+unsigned int rxrpc_resend_timeout = 4 * HZ;
+
+static int rxrpc_send_data(struct rxrpc_sock *rx,
+			   struct rxrpc_call *call,
+			   struct msghdr *msg, size_t len);
+
+/*
+ * extract control messages from the sendmsg() control buffer
+ */
+static int rxrpc_sendmsg_cmsg(struct msghdr *msg,
+			      unsigned long *user_call_ID,
+			      enum rxrpc_command *command,
+			      u32 *abort_code)
+{
+	struct cmsghdr *cmsg;
+	bool got_user_ID = false;
+	int len;
+
+	*command = RXRPC_CMD_SEND_DATA;
+
+	if (msg->msg_controllen == 0)
+		return -EINVAL;
+
+	for_each_cmsghdr(cmsg, msg) {
+		if (!CMSG_OK(msg, cmsg))
+			return -EINVAL;
+
+		len = cmsg->cmsg_len - CMSG_ALIGN(sizeof(struct cmsghdr));
+		_debug("CMSG %d, %d, %d",
+		       cmsg->cmsg_level, cmsg->cmsg_type, len);
+
+		if (cmsg->cmsg_level != SOL_RXRPC)
+			continue;
+
+		switch (cmsg->cmsg_type) {
+		case RXRPC_USER_CALL_ID:
+			if (msg->msg_flags & MSG_CMSG_COMPAT) {
+				if (len != sizeof(u32))
+					return -EINVAL;
+				*user_call_ID = *(u32 *) CMSG_DATA(cmsg);
+			} else {
+				if (len != sizeof(unsigned long))
+					return -EINVAL;
+				*user_call_ID = *(unsigned long *)
+					CMSG_DATA(cmsg);
+			}
+			_debug("User Call ID %lx", *user_call_ID);
+			got_user_ID = true;
+			break;
+
+		case RXRPC_ABORT:
+			if (*command != RXRPC_CMD_SEND_DATA)
+				return -EINVAL;
+			*command = RXRPC_CMD_SEND_ABORT;
+			if (len != sizeof(*abort_code))
+				return -EINVAL;
+			*abort_code = *(unsigned int *) CMSG_DATA(cmsg);
+			_debug("Abort %x", *abort_code);
+			if (*abort_code == 0)
+				return -EINVAL;
+			break;
+
+		case RXRPC_ACCEPT:
+			if (*command != RXRPC_CMD_SEND_DATA)
+				return -EINVAL;
+			*command = RXRPC_CMD_ACCEPT;
+			if (len != 0)
+				return -EINVAL;
+			break;
+
+		default:
+			return -EINVAL;
+		}
+	}
+
+	if (!got_user_ID)
+		return -EINVAL;
+	_leave(" = 0");
+	return 0;
+}
+
+/*
+ * abort a call, sending an ABORT packet to the peer
+ */
+static void rxrpc_send_abort(struct rxrpc_call *call, u32 abort_code)
+{
+	write_lock_bh(&call->state_lock);
+
+	if (call->state <= RXRPC_CALL_COMPLETE) {
+		call->state = RXRPC_CALL_LOCALLY_ABORTED;
+		call->local_abort = abort_code;
+		set_bit(RXRPC_CALL_EV_ABORT, &call->events);
+		del_timer_sync(&call->resend_timer);
+		del_timer_sync(&call->ack_timer);
+		clear_bit(RXRPC_CALL_EV_RESEND_TIMER, &call->events);
+		clear_bit(RXRPC_CALL_EV_ACK, &call->events);
+		clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags);
+		rxrpc_queue_call(call);
+	}
+
+	write_unlock_bh(&call->state_lock);
+}
+
+/*
+ * Create a new client call for sendmsg().
+ */
+static struct rxrpc_call *
+rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
+				  unsigned long user_call_ID)
+{
+	struct rxrpc_conn_bundle *bundle;
+	struct rxrpc_transport *trans;
+	struct rxrpc_call *call;
+	struct key *key;
+	long ret;
+
+	DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
+
+	_enter("");
+
+	if (!msg->msg_name)
+		return ERR_PTR(-EDESTADDRREQ);
+
+	trans = rxrpc_name_to_transport(rx, msg->msg_name, msg->msg_namelen, 0,
+					GFP_KERNEL);
+	if (IS_ERR(trans)) {
+		ret = PTR_ERR(trans);
+		goto out;
+	}
+
+	key = rx->key;
+	if (key && !rx->key->payload.data[0])
+		key = NULL;
+	bundle = rxrpc_get_bundle(rx, trans, key, srx->srx_service, GFP_KERNEL);
+	if (IS_ERR(bundle)) {
+		ret = PTR_ERR(bundle);
+		goto out_trans;
+	}
+
+	call = rxrpc_new_client_call(rx, trans, bundle, user_call_ID,
+				     GFP_KERNEL);
+	rxrpc_put_bundle(trans, bundle);
+	rxrpc_put_transport(trans);
+	if (IS_ERR(call)) {
+		ret = PTR_ERR(call);
+		goto out_trans;
+	}
+
+	_leave(" = %p\n", call);
+	return call;
+
+out_trans:
+	rxrpc_put_transport(trans);
+out:
+	_leave(" = %ld", ret);
+	return ERR_PTR(ret);
+}
+
+/*
+ * send a message forming part of a client call through an RxRPC socket
+ * - caller holds the socket locked
+ * - the socket may be either a client socket or a server socket
+ */
+int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
+{
+	enum rxrpc_command cmd;
+	struct rxrpc_call *call;
+	unsigned long user_call_ID = 0;
+	u32 abort_code = 0;
+	int ret;
+
+	_enter("");
+
+	ret = rxrpc_sendmsg_cmsg(msg, &user_call_ID, &cmd, &abort_code);
+	if (ret < 0)
+		return ret;
+
+	if (cmd == RXRPC_CMD_ACCEPT) {
+		if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
+			return -EINVAL;
+		call = rxrpc_accept_call(rx, user_call_ID);
+		if (IS_ERR(call))
+			return PTR_ERR(call);
+		rxrpc_put_call(call);
+		return 0;
+	}
+
+	call = rxrpc_find_call_by_user_ID(rx, user_call_ID);
+	if (!call) {
+		if (cmd != RXRPC_CMD_SEND_DATA)
+			return -EBADSLT;
+		call = rxrpc_new_client_call_for_sendmsg(rx, msg, user_call_ID);
+		if (IS_ERR(call))
+			return PTR_ERR(call);
+	}
+
+	_debug("CALL %d USR %lx ST %d on CONN %p",
+	       call->debug_id, call->user_call_ID, call->state, call->conn);
+
+	if (call->state >= RXRPC_CALL_COMPLETE) {
+		/* it's too late for this call */
+		ret = -ECONNRESET;
+	} else if (cmd == RXRPC_CMD_SEND_ABORT) {
+		rxrpc_send_abort(call, abort_code);
+		ret = 0;
+	} else if (cmd != RXRPC_CMD_SEND_DATA) {
+		ret = -EINVAL;
+	} else if (!call->in_clientflag &&
+		   call->state != RXRPC_CALL_CLIENT_SEND_REQUEST) {
+		/* request phase complete for this client call */
+		ret = -EPROTO;
+	} else if (call->in_clientflag &&
+		   call->state != RXRPC_CALL_SERVER_ACK_REQUEST &&
+		   call->state != RXRPC_CALL_SERVER_SEND_REPLY) {
+		/* Reply phase not begun or not complete for service call. */
+		ret = -EPROTO;
+	} else {
+		ret = rxrpc_send_data(rx, call, msg, len);
+	}
+
+	rxrpc_put_call(call);
+	_leave(" = %d", ret);
+	return ret;
+}
+
+/**
+ * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
+ * @call: The call to send data through
+ * @msg: The data to send
+ * @len: The amount of data to send
+ *
+ * Allow a kernel service to send data on a call.  The call must be in an state
+ * appropriate to sending data.  No control data should be supplied in @msg,
+ * nor should an address be supplied.  MSG_MORE should be flagged if there's
+ * more data to come, otherwise this data will end the transmission phase.
+ */
+int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg,
+			   size_t len)
+{
+	int ret;
+
+	_enter("{%d,%s},", call->debug_id, rxrpc_call_states[call->state]);
+
+	ASSERTCMP(msg->msg_name, ==, NULL);
+	ASSERTCMP(msg->msg_control, ==, NULL);
+
+	lock_sock(&call->socket->sk);
+
+	_debug("CALL %d USR %lx ST %d on CONN %p",
+	       call->debug_id, call->user_call_ID, call->state, call->conn);
+
+	if (call->state >= RXRPC_CALL_COMPLETE) {
+		ret = -ESHUTDOWN; /* it's too late for this call */
+	} else if (call->state != RXRPC_CALL_CLIENT_SEND_REQUEST &&
+		   call->state != RXRPC_CALL_SERVER_ACK_REQUEST &&
+		   call->state != RXRPC_CALL_SERVER_SEND_REPLY) {
+		ret = -EPROTO; /* request phase complete for this client call */
+	} else {
+		ret = rxrpc_send_data(call->socket, call, msg, len);
+	}
+
+	release_sock(&call->socket->sk);
+	_leave(" = %d", ret);
+	return ret;
+}
+
+EXPORT_SYMBOL(rxrpc_kernel_send_data);
+
+/**
+ * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
+ * @call: The call to be aborted
+ * @abort_code: The abort code to stick into the ABORT packet
+ *
+ * Allow a kernel service to abort a call, if it's still in an abortable state.
+ */
+void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code)
+{
+	_enter("{%d},%d", call->debug_id, abort_code);
+
+	lock_sock(&call->socket->sk);
+
+	_debug("CALL %d USR %lx ST %d on CONN %p",
+	       call->debug_id, call->user_call_ID, call->state, call->conn);
+
+	if (call->state < RXRPC_CALL_COMPLETE)
+		rxrpc_send_abort(call, abort_code);
+
+	release_sock(&call->socket->sk);
+	_leave("");
+}
+
+EXPORT_SYMBOL(rxrpc_kernel_abort_call);
+
+/*
+ * send a packet through the transport endpoint
+ */
+int rxrpc_send_packet(struct rxrpc_transport *trans, struct sk_buff *skb)
+{
+	struct kvec iov[1];
+	struct msghdr msg;
+	int ret, opt;
+
+	_enter(",{%d}", skb->len);
+
+	iov[0].iov_base = skb->head;
+	iov[0].iov_len = skb->len;
+
+	msg.msg_name = &trans->peer->srx.transport.sin;
+	msg.msg_namelen = sizeof(trans->peer->srx.transport.sin);
+	msg.msg_control = NULL;
+	msg.msg_controllen = 0;
+	msg.msg_flags = 0;
+
+	/* send the packet with the don't fragment bit set if we currently
+	 * think it's small enough */
+	if (skb->len - sizeof(struct rxrpc_wire_header) < trans->peer->maxdata) {
+		down_read(&trans->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(trans->local->socket, &msg, iov, 1,
+				     iov[0].iov_len);
+
+		up_read(&trans->local->defrag_sem);
+		if (ret == -EMSGSIZE)
+			goto send_fragmentable;
+
+		_leave(" = %d [%u]", ret, trans->peer->maxdata);
+		return ret;
+	}
+
+send_fragmentable:
+	/* attempt to send this message with fragmentation enabled */
+	_debug("send fragment");
+
+	down_write(&trans->local->defrag_sem);
+	opt = IP_PMTUDISC_DONT;
+	ret = kernel_setsockopt(trans->local->socket, SOL_IP, IP_MTU_DISCOVER,
+				(char *) &opt, sizeof(opt));
+	if (ret == 0) {
+		ret = kernel_sendmsg(trans->local->socket, &msg, iov, 1,
+				     iov[0].iov_len);
+
+		opt = IP_PMTUDISC_DO;
+		kernel_setsockopt(trans->local->socket, SOL_IP,
+				  IP_MTU_DISCOVER, (char *) &opt, sizeof(opt));
+	}
+
+	up_write(&trans->local->defrag_sem);
+	_leave(" = %d [frag %u]", ret, trans->peer->maxdata);
+	return ret;
+}
+
+/*
+ * wait for space to appear in the transmit/ACK window
+ * - caller holds the socket locked
+ */
+static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
+				    struct rxrpc_call *call,
+				    long *timeo)
+{
+	DECLARE_WAITQUEUE(myself, current);
+	int ret;
+
+	_enter(",{%d},%ld",
+	       CIRC_SPACE(call->acks_head, ACCESS_ONCE(call->acks_tail),
+			  call->acks_winsz),
+	       *timeo);
+
+	add_wait_queue(&call->tx_waitq, &myself);
+
+	for (;;) {
+		set_current_state(TASK_INTERRUPTIBLE);
+		ret = 0;
+		if (CIRC_SPACE(call->acks_head, ACCESS_ONCE(call->acks_tail),
+			       call->acks_winsz) > 0)
+			break;
+		if (signal_pending(current)) {
+			ret = sock_intr_errno(*timeo);
+			break;
+		}
+
+		release_sock(&rx->sk);
+		*timeo = schedule_timeout(*timeo);
+		lock_sock(&rx->sk);
+	}
+
+	remove_wait_queue(&call->tx_waitq, &myself);
+	set_current_state(TASK_RUNNING);
+	_leave(" = %d", ret);
+	return ret;
+}
+
+/*
+ * attempt to schedule an instant Tx resend
+ */
+static inline void rxrpc_instant_resend(struct rxrpc_call *call)
+{
+	read_lock_bh(&call->state_lock);
+	if (try_to_del_timer_sync(&call->resend_timer) >= 0) {
+		clear_bit(RXRPC_CALL_RUN_RTIMER, &call->flags);
+		if (call->state < RXRPC_CALL_COMPLETE &&
+		    !test_and_set_bit(RXRPC_CALL_EV_RESEND_TIMER, &call->events))
+			rxrpc_queue_call(call);
+	}
+	read_unlock_bh(&call->state_lock);
+}
+
+/*
+ * queue a packet for transmission, set the resend timer and attempt
+ * to send the packet immediately
+ */
+static void rxrpc_queue_packet(struct rxrpc_call *call, struct sk_buff *skb,
+			       bool last)
+{
+	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+	int ret;
+
+	_net("queue skb %p [%d]", skb, call->acks_head);
+
+	ASSERT(call->acks_window != NULL);
+	call->acks_window[call->acks_head] = (unsigned long) skb;
+	smp_wmb();
+	call->acks_head = (call->acks_head + 1) & (call->acks_winsz - 1);
+
+	if (last || call->state == RXRPC_CALL_SERVER_ACK_REQUEST) {
+		_debug("________awaiting reply/ACK__________");
+		write_lock_bh(&call->state_lock);
+		switch (call->state) {
+		case RXRPC_CALL_CLIENT_SEND_REQUEST:
+			call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
+			break;
+		case RXRPC_CALL_SERVER_ACK_REQUEST:
+			call->state = RXRPC_CALL_SERVER_SEND_REPLY;
+			if (!last)
+				break;
+		case RXRPC_CALL_SERVER_SEND_REPLY:
+			call->state = RXRPC_CALL_SERVER_AWAIT_ACK;
+			break;
+		default:
+			break;
+		}
+		write_unlock_bh(&call->state_lock);
+	}
+
+	_proto("Tx DATA %%%u { #%u }", sp->hdr.serial, sp->hdr.seq);
+
+	sp->need_resend = false;
+	sp->resend_at = jiffies + rxrpc_resend_timeout;
+	if (!test_and_set_bit(RXRPC_CALL_RUN_RTIMER, &call->flags)) {
+		_debug("run timer");
+		call->resend_timer.expires = sp->resend_at;
+		add_timer(&call->resend_timer);
+	}
+
+	/* attempt to cancel the rx-ACK timer, deferring reply transmission if
+	 * we're ACK'ing the request phase of an incoming call */
+	ret = -EAGAIN;
+	if (try_to_del_timer_sync(&call->ack_timer) >= 0) {
+		/* the packet may be freed by rxrpc_process_call() before this
+		 * returns */
+		ret = rxrpc_send_packet(call->conn->trans, skb);
+		_net("sent skb %p", skb);
+	} else {
+		_debug("failed to delete ACK timer");
+	}
+
+	if (ret < 0) {
+		_debug("need instant resend %d", ret);
+		sp->need_resend = true;
+		rxrpc_instant_resend(call);
+	}
+
+	_leave("");
+}
+
+/*
+ * Convert a host-endian header into a network-endian header.
+ */
+static void rxrpc_insert_header(struct sk_buff *skb)
+{
+	struct rxrpc_wire_header whdr;
+	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+
+	whdr.epoch	= htonl(sp->hdr.epoch);
+	whdr.cid	= htonl(sp->hdr.cid);
+	whdr.callNumber	= htonl(sp->hdr.callNumber);
+	whdr.seq	= htonl(sp->hdr.seq);
+	whdr.serial	= htonl(sp->hdr.serial);
+	whdr.type	= sp->hdr.type;
+	whdr.flags	= sp->hdr.flags;
+	whdr.userStatus	= sp->hdr.userStatus;
+	whdr.securityIndex = sp->hdr.securityIndex;
+	whdr._rsvd	= htons(sp->hdr._rsvd);
+	whdr.serviceId	= htons(sp->hdr.serviceId);
+
+	memcpy(skb->head, &whdr, sizeof(whdr));
+}
+
+/*
+ * send data through a socket
+ * - must be called in process context
+ * - caller holds the socket locked
+ */
+static int rxrpc_send_data(struct rxrpc_sock *rx,
+			   struct rxrpc_call *call,
+			   struct msghdr *msg, size_t len)
+{
+	struct rxrpc_skb_priv *sp;
+	struct sk_buff *skb;
+	struct sock *sk = &rx->sk;
+	long timeo;
+	bool more;
+	int ret, copied;
+
+	timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
+
+	/* this should be in poll */
+	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
+
+	if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
+		return -EPIPE;
+
+	more = msg->msg_flags & MSG_MORE;
+
+	skb = call->tx_pending;
+	call->tx_pending = NULL;
+
+	copied = 0;
+	do {
+		if (!skb) {
+			size_t size, chunk, max, space;
+
+			_debug("alloc");
+
+			if (CIRC_SPACE(call->acks_head,
+				       ACCESS_ONCE(call->acks_tail),
+				       call->acks_winsz) <= 0) {
+				ret = -EAGAIN;
+				if (msg->msg_flags & MSG_DONTWAIT)
+					goto maybe_error;
+				ret = rxrpc_wait_for_tx_window(rx, call,
+							       &timeo);
+				if (ret < 0)
+					goto maybe_error;
+			}
+
+			max = call->conn->trans->peer->maxdata;
+			max -= call->conn->security_size;
+			max &= ~(call->conn->size_align - 1UL);
+
+			chunk = max;
+			if (chunk > msg_data_left(msg) && !more)
+				chunk = msg_data_left(msg);
+
+			space = chunk + call->conn->size_align;
+			space &= ~(call->conn->size_align - 1UL);
+
+			size = space + call->conn->header_size;
+
+			_debug("SIZE: %zu/%zu/%zu", chunk, space, size);
+
+			/* create a buffer that we can retain until it's ACK'd */
+			skb = sock_alloc_send_skb(
+				sk, size, msg->msg_flags & MSG_DONTWAIT, &ret);
+			if (!skb)
+				goto maybe_error;
+
+			rxrpc_new_skb(skb);
+
+			_debug("ALLOC SEND %p", skb);
+
+			ASSERTCMP(skb->mark, ==, 0);
+
+			_debug("HS: %u", call->conn->header_size);
+			skb_reserve(skb, call->conn->header_size);
+			skb->len += call->conn->header_size;
+
+			sp = rxrpc_skb(skb);
+			sp->remain = chunk;
+			if (sp->remain > skb_tailroom(skb))
+				sp->remain = skb_tailroom(skb);
+
+			_net("skb: hr %d, tr %d, hl %d, rm %d",
+			       skb_headroom(skb),
+			       skb_tailroom(skb),
+			       skb_headlen(skb),
+			       sp->remain);
+
+			skb->ip_summed = CHECKSUM_UNNECESSARY;
+		}
+
+		_debug("append");
+		sp = rxrpc_skb(skb);
+
+		/* append next segment of data to the current buffer */
+		if (msg_data_left(msg) > 0) {
+			int copy = skb_tailroom(skb);
+			ASSERTCMP(copy, >, 0);
+			if (copy > msg_data_left(msg))
+				copy = msg_data_left(msg);
+			if (copy > sp->remain)
+				copy = sp->remain;
+
+			_debug("add");
+			ret = skb_add_data(skb, &msg->msg_iter, copy);
+			_debug("added");
+			if (ret < 0)
+				goto efault;
+			sp->remain -= copy;
+			skb->mark += copy;
+			copied += copy;
+		}
+
+		/* check for the far side aborting the call or a network error
+		 * occurring */
+		if (call->state > RXRPC_CALL_COMPLETE)
+			goto call_aborted;
+
+		/* add the packet to the send queue if it's now full */
+		if (sp->remain <= 0 ||
+		    (msg_data_left(msg) == 0 && !more)) {
+			struct rxrpc_connection *conn = call->conn;
+			uint32_t seq;
+			size_t pad;
+
+			/* pad out if we're using security */
+			if (conn->security_ix) {
+				pad = conn->security_size + skb->mark;
+				pad = conn->size_align - pad;
+				pad &= conn->size_align - 1;
+				_debug("pad %zu", pad);
+				if (pad)
+					memset(skb_put(skb, pad), 0, pad);
+			}
+
+			seq = atomic_inc_return(&call->sequence);
+
+			sp->hdr.epoch	= conn->epoch;
+			sp->hdr.cid	= call->cid;
+			sp->hdr.callNumber = call->call_id;
+			sp->hdr.seq	= seq;
+			sp->hdr.serial	= atomic_inc_return(&conn->serial);
+			sp->hdr.type	= RXRPC_PACKET_TYPE_DATA;
+			sp->hdr.userStatus = 0;
+			sp->hdr.securityIndex = conn->security_ix;
+			sp->hdr._rsvd	= 0;
+			sp->hdr.serviceId = call->service_id;
+
+			sp->hdr.flags = conn->out_clientflag;
+			if (msg_data_left(msg) == 0 && !more)
+				sp->hdr.flags |= RXRPC_LAST_PACKET;
+			else if (CIRC_SPACE(call->acks_head,
+					    ACCESS_ONCE(call->acks_tail),
+					    call->acks_winsz) > 1)
+				sp->hdr.flags |= RXRPC_MORE_PACKETS;
+			if (more && seq & 1)
+				sp->hdr.flags |= RXRPC_REQUEST_ACK;
+
+			ret = conn->security->secure_packet(
+				call, skb, skb->mark,
+				skb->head + sizeof(struct rxrpc_wire_header));
+			if (ret < 0)
+				goto out;
+
+			rxrpc_insert_header(skb);
+			rxrpc_queue_packet(call, skb, !msg_data_left(msg) && !more);
+			skb = NULL;
+		}
+	} while (msg_data_left(msg) > 0);
+
+success:
+	ret = copied;
+out:
+	call->tx_pending = skb;
+	_leave(" = %d", ret);
+	return ret;
+
+call_aborted:
+	rxrpc_free_skb(skb);
+	if (call->state == RXRPC_CALL_NETWORK_ERROR)
+		ret = call->conn->trans->peer->net_error;
+	else
+		ret = -ECONNABORTED;
+	_leave(" = %d", ret);
+	return ret;
+
+maybe_error:
+	if (copied)
+		goto success;
+	goto out;
+
+efault:
+	ret = -EFAULT;
+	goto out;
+}