initial_commit

1 files changed, 1355 insertions, 0 deletions

diff --git a/net/tipc/port.c b/net/tipc/port.c
new file mode 100644
index 00000000..c68dc956
--- /dev/null
+++ b/net/tipc/port.c
@@ -0,0 +1,1355 @@
+/*
+ * net/tipc/port.c: TIPC port code
+ *
+ * Copyright (c) 1992-2007, Ericsson AB
+ * Copyright (c) 2004-2008, 2010-2011, Wind River Systems
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the names of the copyright holders nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "core.h"
+#include "config.h"
+#include "port.h"
+#include "name_table.h"
+
+/* Connection management: */
+#define PROBING_INTERVAL 3600000	/* [ms] => 1 h */
+#define CONFIRMED 0
+#define PROBING 1
+
+#define MAX_REJECT_SIZE 1024
+
+static struct sk_buff *msg_queue_head;
+static struct sk_buff *msg_queue_tail;
+
+DEFINE_SPINLOCK(tipc_port_list_lock);
+static DEFINE_SPINLOCK(queue_lock);
+
+static LIST_HEAD(ports);
+static void port_handle_node_down(unsigned long ref);
+static struct sk_buff *port_build_self_abort_msg(struct tipc_port *, u32 err);
+static struct sk_buff *port_build_peer_abort_msg(struct tipc_port *, u32 err);
+static void port_timeout(unsigned long ref);
+
+
+static u32 port_peernode(struct tipc_port *p_ptr)
+{
+	return msg_destnode(&p_ptr->phdr);
+}
+
+static u32 port_peerport(struct tipc_port *p_ptr)
+{
+	return msg_destport(&p_ptr->phdr);
+}
+
+/**
+ * tipc_multicast - send a multicast message to local and remote destinations
+ */
+
+int tipc_multicast(u32 ref, struct tipc_name_seq const *seq,
+		   u32 num_sect, struct iovec const *msg_sect,
+		   unsigned int total_len)
+{
+	struct tipc_msg *hdr;
+	struct sk_buff *buf;
+	struct sk_buff *ibuf = NULL;
+	struct port_list dports = {0, NULL, };
+	struct tipc_port *oport = tipc_port_deref(ref);
+	int ext_targets;
+	int res;
+
+	if (unlikely(!oport))
+		return -EINVAL;
+
+	/* Create multicast message */
+
+	hdr = &oport->phdr;
+	msg_set_type(hdr, TIPC_MCAST_MSG);
+	msg_set_lookup_scope(hdr, TIPC_CLUSTER_SCOPE);
+	msg_set_destport(hdr, 0);
+	msg_set_destnode(hdr, 0);
+	msg_set_nametype(hdr, seq->type);
+	msg_set_namelower(hdr, seq->lower);
+	msg_set_nameupper(hdr, seq->upper);
+	msg_set_hdr_sz(hdr, MCAST_H_SIZE);
+	res = tipc_msg_build(hdr, msg_sect, num_sect, total_len, MAX_MSG_SIZE,
+			!oport->user_port, &buf);
+	if (unlikely(!buf))
+		return res;
+
+	/* Figure out where to send multicast message */
+
+	ext_targets = tipc_nametbl_mc_translate(seq->type, seq->lower, seq->upper,
+						TIPC_NODE_SCOPE, &dports);
+
+	/* Send message to destinations (duplicate it only if necessary) */
+
+	if (ext_targets) {
+		if (dports.count != 0) {
+			ibuf = skb_copy(buf, GFP_ATOMIC);
+			if (ibuf == NULL) {
+				tipc_port_list_free(&dports);
+				buf_discard(buf);
+				return -ENOMEM;
+			}
+		}
+		res = tipc_bclink_send_msg(buf);
+		if ((res < 0) && (dports.count != 0))
+			buf_discard(ibuf);
+	} else {
+		ibuf = buf;
+	}
+
+	if (res >= 0) {
+		if (ibuf)
+			tipc_port_recv_mcast(ibuf, &dports);
+	} else {
+		tipc_port_list_free(&dports);
+	}
+	return res;
+}
+
+/**
+ * tipc_port_recv_mcast - deliver multicast message to all destination ports
+ *
+ * If there is no port list, perform a lookup to create one
+ */
+
+void tipc_port_recv_mcast(struct sk_buff *buf, struct port_list *dp)
+{
+	struct tipc_msg *msg;
+	struct port_list dports = {0, NULL, };
+	struct port_list *item = dp;
+	int cnt = 0;
+
+	msg = buf_msg(buf);
+
+	/* Create destination port list, if one wasn't supplied */
+
+	if (dp == NULL) {
+		tipc_nametbl_mc_translate(msg_nametype(msg),
+				     msg_namelower(msg),
+				     msg_nameupper(msg),
+				     TIPC_CLUSTER_SCOPE,
+				     &dports);
+		item = dp = &dports;
+	}
+
+	/* Deliver a copy of message to each destination port */
+
+	if (dp->count != 0) {
+		msg_set_destnode(msg, tipc_own_addr);
+		if (dp->count == 1) {
+			msg_set_destport(msg, dp->ports[0]);
+			tipc_port_recv_msg(buf);
+			tipc_port_list_free(dp);
+			return;
+		}
+		for (; cnt < dp->count; cnt++) {
+			int index = cnt % PLSIZE;
+			struct sk_buff *b = skb_clone(buf, GFP_ATOMIC);
+
+			if (b == NULL) {
+				warn("Unable to deliver multicast message(s)\n");
+				goto exit;
+			}
+			if ((index == 0) && (cnt != 0))
+				item = item->next;
+			msg_set_destport(buf_msg(b), item->ports[index]);
+			tipc_port_recv_msg(b);
+		}
+	}
+exit:
+	buf_discard(buf);
+	tipc_port_list_free(dp);
+}
+
+/**
+ * tipc_createport_raw - create a generic TIPC port
+ *
+ * Returns pointer to (locked) TIPC port, or NULL if unable to create it
+ */
+
+struct tipc_port *tipc_createport_raw(void *usr_handle,
+			u32 (*dispatcher)(struct tipc_port *, struct sk_buff *),
+			void (*wakeup)(struct tipc_port *),
+			const u32 importance)
+{
+	struct tipc_port *p_ptr;
+	struct tipc_msg *msg;
+	u32 ref;
+
+	p_ptr = kzalloc(sizeof(*p_ptr), GFP_ATOMIC);
+	if (!p_ptr) {
+		warn("Port creation failed, no memory\n");
+		return NULL;
+	}
+	ref = tipc_ref_acquire(p_ptr, &p_ptr->lock);
+	if (!ref) {
+		warn("Port creation failed, reference table exhausted\n");
+		kfree(p_ptr);
+		return NULL;
+	}
+
+	p_ptr->usr_handle = usr_handle;
+	p_ptr->max_pkt = MAX_PKT_DEFAULT;
+	p_ptr->ref = ref;
+	msg = &p_ptr->phdr;
+	tipc_msg_init(msg, importance, TIPC_NAMED_MSG, LONG_H_SIZE, 0);
+	msg_set_origport(msg, ref);
+	INIT_LIST_HEAD(&p_ptr->wait_list);
+	INIT_LIST_HEAD(&p_ptr->subscription.nodesub_list);
+	p_ptr->dispatcher = dispatcher;
+	p_ptr->wakeup = wakeup;
+	p_ptr->user_port = NULL;
+	k_init_timer(&p_ptr->timer, (Handler)port_timeout, ref);
+	spin_lock_bh(&tipc_port_list_lock);
+	INIT_LIST_HEAD(&p_ptr->publications);
+	INIT_LIST_HEAD(&p_ptr->port_list);
+	list_add_tail(&p_ptr->port_list, &ports);
+	spin_unlock_bh(&tipc_port_list_lock);
+	return p_ptr;
+}
+
+int tipc_deleteport(u32 ref)
+{
+	struct tipc_port *p_ptr;
+	struct sk_buff *buf = NULL;
+
+	tipc_withdraw(ref, 0, NULL);
+	p_ptr = tipc_port_lock(ref);
+	if (!p_ptr)
+		return -EINVAL;
+
+	tipc_ref_discard(ref);
+	tipc_port_unlock(p_ptr);
+
+	k_cancel_timer(&p_ptr->timer);
+	if (p_ptr->connected) {
+		buf = port_build_peer_abort_msg(p_ptr, TIPC_ERR_NO_PORT);
+		tipc_nodesub_unsubscribe(&p_ptr->subscription);
+	}
+	kfree(p_ptr->user_port);
+
+	spin_lock_bh(&tipc_port_list_lock);
+	list_del(&p_ptr->port_list);
+	list_del(&p_ptr->wait_list);
+	spin_unlock_bh(&tipc_port_list_lock);
+	k_term_timer(&p_ptr->timer);
+	kfree(p_ptr);
+	tipc_net_route_msg(buf);
+	return 0;
+}
+
+static int port_unreliable(struct tipc_port *p_ptr)
+{
+	return msg_src_droppable(&p_ptr->phdr);
+}
+
+int tipc_portunreliable(u32 ref, unsigned int *isunreliable)
+{
+	struct tipc_port *p_ptr;
+
+	p_ptr = tipc_port_lock(ref);
+	if (!p_ptr)
+		return -EINVAL;
+	*isunreliable = port_unreliable(p_ptr);
+	tipc_port_unlock(p_ptr);
+	return 0;
+}
+
+int tipc_set_portunreliable(u32 ref, unsigned int isunreliable)
+{
+	struct tipc_port *p_ptr;
+
+	p_ptr = tipc_port_lock(ref);
+	if (!p_ptr)
+		return -EINVAL;
+	msg_set_src_droppable(&p_ptr->phdr, (isunreliable != 0));
+	tipc_port_unlock(p_ptr);
+	return 0;
+}
+
+static int port_unreturnable(struct tipc_port *p_ptr)
+{
+	return msg_dest_droppable(&p_ptr->phdr);
+}
+
+int tipc_portunreturnable(u32 ref, unsigned int *isunrejectable)
+{
+	struct tipc_port *p_ptr;
+
+	p_ptr = tipc_port_lock(ref);
+	if (!p_ptr)
+		return -EINVAL;
+	*isunrejectable = port_unreturnable(p_ptr);
+	tipc_port_unlock(p_ptr);
+	return 0;
+}
+
+int tipc_set_portunreturnable(u32 ref, unsigned int isunrejectable)
+{
+	struct tipc_port *p_ptr;
+
+	p_ptr = tipc_port_lock(ref);
+	if (!p_ptr)
+		return -EINVAL;
+	msg_set_dest_droppable(&p_ptr->phdr, (isunrejectable != 0));
+	tipc_port_unlock(p_ptr);
+	return 0;
+}
+
+/*
+ * port_build_proto_msg(): build a port level protocol
+ * or a connection abortion message. Called with
+ * tipc_port lock on.
+ */
+static struct sk_buff *port_build_proto_msg(u32 destport, u32 destnode,
+					    u32 origport, u32 orignode,
+					    u32 usr, u32 type, u32 err,
+					    u32 ack)
+{
+	struct sk_buff *buf;
+	struct tipc_msg *msg;
+
+	buf = tipc_buf_acquire(LONG_H_SIZE);
+	if (buf) {
+		msg = buf_msg(buf);
+		tipc_msg_init(msg, usr, type, LONG_H_SIZE, destnode);
+		msg_set_errcode(msg, err);
+		msg_set_destport(msg, destport);
+		msg_set_origport(msg, origport);
+		msg_set_orignode(msg, orignode);
+		msg_set_msgcnt(msg, ack);
+	}
+	return buf;
+}
+
+int tipc_reject_msg(struct sk_buff *buf, u32 err)
+{
+	struct tipc_msg *msg = buf_msg(buf);
+	struct sk_buff *rbuf;
+	struct tipc_msg *rmsg;
+	int hdr_sz;
+	u32 imp = msg_importance(msg);
+	u32 data_sz = msg_data_sz(msg);
+
+	if (data_sz > MAX_REJECT_SIZE)
+		data_sz = MAX_REJECT_SIZE;
+	if (msg_connected(msg) && (imp < TIPC_CRITICAL_IMPORTANCE))
+		imp++;
+
+	/* discard rejected message if it shouldn't be returned to sender */
+	if (msg_errcode(msg) || msg_dest_droppable(msg)) {
+		buf_discard(buf);
+		return data_sz;
+	}
+
+	/* construct rejected message */
+	if (msg_mcast(msg))
+		hdr_sz = MCAST_H_SIZE;
+	else
+		hdr_sz = LONG_H_SIZE;
+	rbuf = tipc_buf_acquire(data_sz + hdr_sz);
+	if (rbuf == NULL) {
+		buf_discard(buf);
+		return data_sz;
+	}
+	rmsg = buf_msg(rbuf);
+	tipc_msg_init(rmsg, imp, msg_type(msg), hdr_sz, msg_orignode(msg));
+	msg_set_errcode(rmsg, err);
+	msg_set_destport(rmsg, msg_origport(msg));
+	msg_set_origport(rmsg, msg_destport(msg));
+	if (msg_short(msg)) {
+		msg_set_orignode(rmsg, tipc_own_addr);
+		/* leave name type & instance as zeroes */
+	} else {
+		msg_set_orignode(rmsg, msg_destnode(msg));
+		msg_set_nametype(rmsg, msg_nametype(msg));
+		msg_set_nameinst(rmsg, msg_nameinst(msg));
+	}
+	msg_set_size(rmsg, data_sz + hdr_sz);
+	skb_copy_to_linear_data_offset(rbuf, hdr_sz, msg_data(msg), data_sz);
+
+	/* send self-abort message when rejecting on a connected port */
+	if (msg_connected(msg)) {
+		struct sk_buff *abuf = NULL;
+		struct tipc_port *p_ptr = tipc_port_lock(msg_destport(msg));
+
+		if (p_ptr) {
+			if (p_ptr->connected)
+				abuf = port_build_self_abort_msg(p_ptr, err);
+			tipc_port_unlock(p_ptr);
+		}
+		tipc_net_route_msg(abuf);
+	}
+
+	/* send rejected message */
+	buf_discard(buf);
+	tipc_net_route_msg(rbuf);
+	return data_sz;
+}
+
+int tipc_port_reject_sections(struct tipc_port *p_ptr, struct tipc_msg *hdr,
+			      struct iovec const *msg_sect, u32 num_sect,
+			      unsigned int total_len, int err)
+{
+	struct sk_buff *buf;
+	int res;
+
+	res = tipc_msg_build(hdr, msg_sect, num_sect, total_len, MAX_MSG_SIZE,
+			!p_ptr->user_port, &buf);
+	if (!buf)
+		return res;
+
+	return tipc_reject_msg(buf, err);
+}
+
+static void port_timeout(unsigned long ref)
+{
+	struct tipc_port *p_ptr = tipc_port_lock(ref);
+	struct sk_buff *buf = NULL;
+
+	if (!p_ptr)
+		return;
+
+	if (!p_ptr->connected) {
+		tipc_port_unlock(p_ptr);
+		return;
+	}
+
+	/* Last probe answered ? */
+	if (p_ptr->probing_state == PROBING) {
+		buf = port_build_self_abort_msg(p_ptr, TIPC_ERR_NO_PORT);
+	} else {
+		buf = port_build_proto_msg(port_peerport(p_ptr),
+					   port_peernode(p_ptr),
+					   p_ptr->ref,
+					   tipc_own_addr,
+					   CONN_MANAGER,
+					   CONN_PROBE,
+					   TIPC_OK,
+					   0);
+		p_ptr->probing_state = PROBING;
+		k_start_timer(&p_ptr->timer, p_ptr->probing_interval);
+	}
+	tipc_port_unlock(p_ptr);
+	tipc_net_route_msg(buf);
+}
+
+
+static void port_handle_node_down(unsigned long ref)
+{
+	struct tipc_port *p_ptr = tipc_port_lock(ref);
+	struct sk_buff *buf = NULL;
+
+	if (!p_ptr)
+		return;
+	buf = port_build_self_abort_msg(p_ptr, TIPC_ERR_NO_NODE);
+	tipc_port_unlock(p_ptr);
+	tipc_net_route_msg(buf);
+}
+
+
+static struct sk_buff *port_build_self_abort_msg(struct tipc_port *p_ptr, u32 err)
+{
+	u32 imp = msg_importance(&p_ptr->phdr);
+
+	if (!p_ptr->connected)
+		return NULL;
+	if (imp < TIPC_CRITICAL_IMPORTANCE)
+		imp++;
+	return port_build_proto_msg(p_ptr->ref,
+				    tipc_own_addr,
+				    port_peerport(p_ptr),
+				    port_peernode(p_ptr),
+				    imp,
+				    TIPC_CONN_MSG,
+				    err,
+				    0);
+}
+
+
+static struct sk_buff *port_build_peer_abort_msg(struct tipc_port *p_ptr, u32 err)
+{
+	u32 imp = msg_importance(&p_ptr->phdr);
+
+	if (!p_ptr->connected)
+		return NULL;
+	if (imp < TIPC_CRITICAL_IMPORTANCE)
+		imp++;
+	return port_build_proto_msg(port_peerport(p_ptr),
+				    port_peernode(p_ptr),
+				    p_ptr->ref,
+				    tipc_own_addr,
+				    imp,
+				    TIPC_CONN_MSG,
+				    err,
+				    0);
+}
+
+void tipc_port_recv_proto_msg(struct sk_buff *buf)
+{
+	struct tipc_msg *msg = buf_msg(buf);
+	struct tipc_port *p_ptr = tipc_port_lock(msg_destport(msg));
+	u32 err = TIPC_OK;
+	struct sk_buff *r_buf = NULL;
+	struct sk_buff *abort_buf = NULL;
+
+	if (!p_ptr) {
+		err = TIPC_ERR_NO_PORT;
+	} else if (p_ptr->connected) {
+		if ((port_peernode(p_ptr) != msg_orignode(msg)) ||
+		    (port_peerport(p_ptr) != msg_origport(msg))) {
+			err = TIPC_ERR_NO_PORT;
+		} else if (msg_type(msg) == CONN_ACK) {
+			int wakeup = tipc_port_congested(p_ptr) &&
+				     p_ptr->congested &&
+				     p_ptr->wakeup;
+			p_ptr->acked += msg_msgcnt(msg);
+			if (tipc_port_congested(p_ptr))
+				goto exit;
+			p_ptr->congested = 0;
+			if (!wakeup)
+				goto exit;
+			p_ptr->wakeup(p_ptr);
+			goto exit;
+		}
+	} else if (p_ptr->published) {
+		err = TIPC_ERR_NO_PORT;
+	}
+	if (err) {
+		r_buf = port_build_proto_msg(msg_origport(msg),
+					     msg_orignode(msg),
+					     msg_destport(msg),
+					     tipc_own_addr,
+					     TIPC_HIGH_IMPORTANCE,
+					     TIPC_CONN_MSG,
+					     err,
+					     0);
+		goto exit;
+	}
+
+	/* All is fine */
+	if (msg_type(msg) == CONN_PROBE) {
+		r_buf = port_build_proto_msg(msg_origport(msg),
+					     msg_orignode(msg),
+					     msg_destport(msg),
+					     tipc_own_addr,
+					     CONN_MANAGER,
+					     CONN_PROBE_REPLY,
+					     TIPC_OK,
+					     0);
+	}
+	p_ptr->probing_state = CONFIRMED;
+exit:
+	if (p_ptr)
+		tipc_port_unlock(p_ptr);
+	tipc_net_route_msg(r_buf);
+	tipc_net_route_msg(abort_buf);
+	buf_discard(buf);
+}
+
+static void port_print(struct tipc_port *p_ptr, struct print_buf *buf, int full_id)
+{
+	struct publication *publ;
+
+	if (full_id)
+		tipc_printf(buf, "<%u.%u.%u:%u>:",
+			    tipc_zone(tipc_own_addr), tipc_cluster(tipc_own_addr),
+			    tipc_node(tipc_own_addr), p_ptr->ref);
+	else
+		tipc_printf(buf, "%-10u:", p_ptr->ref);
+
+	if (p_ptr->connected) {
+		u32 dport = port_peerport(p_ptr);
+		u32 destnode = port_peernode(p_ptr);
+
+		tipc_printf(buf, " connected to <%u.%u.%u:%u>",
+			    tipc_zone(destnode), tipc_cluster(destnode),
+			    tipc_node(destnode), dport);
+		if (p_ptr->conn_type != 0)
+			tipc_printf(buf, " via {%u,%u}",
+				    p_ptr->conn_type,
+				    p_ptr->conn_instance);
+	} else if (p_ptr->published) {
+		tipc_printf(buf, " bound to");
+		list_for_each_entry(publ, &p_ptr->publications, pport_list) {
+			if (publ->lower == publ->upper)
+				tipc_printf(buf, " {%u,%u}", publ->type,
+					    publ->lower);
+			else
+				tipc_printf(buf, " {%u,%u,%u}", publ->type,
+					    publ->lower, publ->upper);
+		}
+	}
+	tipc_printf(buf, "\n");
+}
+
+#define MAX_PORT_QUERY 32768
+
+struct sk_buff *tipc_port_get_ports(void)
+{
+	struct sk_buff *buf;
+	struct tlv_desc *rep_tlv;
+	struct print_buf pb;
+	struct tipc_port *p_ptr;
+	int str_len;
+
+	buf = tipc_cfg_reply_alloc(TLV_SPACE(MAX_PORT_QUERY));
+	if (!buf)
+		return NULL;
+	rep_tlv = (struct tlv_desc *)buf->data;
+
+	tipc_printbuf_init(&pb, TLV_DATA(rep_tlv), MAX_PORT_QUERY);
+	spin_lock_bh(&tipc_port_list_lock);
+	list_for_each_entry(p_ptr, &ports, port_list) {
+		spin_lock_bh(p_ptr->lock);
+		port_print(p_ptr, &pb, 0);
+		spin_unlock_bh(p_ptr->lock);
+	}
+	spin_unlock_bh(&tipc_port_list_lock);
+	str_len = tipc_printbuf_validate(&pb);
+
+	skb_put(buf, TLV_SPACE(str_len));
+	TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len);
+
+	return buf;
+}
+
+void tipc_port_reinit(void)
+{
+	struct tipc_port *p_ptr;
+	struct tipc_msg *msg;
+
+	spin_lock_bh(&tipc_port_list_lock);
+	list_for_each_entry(p_ptr, &ports, port_list) {
+		msg = &p_ptr->phdr;
+		if (msg_orignode(msg) == tipc_own_addr)
+			break;
+		msg_set_prevnode(msg, tipc_own_addr);
+		msg_set_orignode(msg, tipc_own_addr);
+	}
+	spin_unlock_bh(&tipc_port_list_lock);
+}
+
+
+/*
+ *  port_dispatcher_sigh(): Signal handler for messages destinated
+ *                          to the tipc_port interface.
+ */
+
+static void port_dispatcher_sigh(void *dummy)
+{
+	struct sk_buff *buf;
+
+	spin_lock_bh(&queue_lock);
+	buf = msg_queue_head;
+	msg_queue_head = NULL;
+	spin_unlock_bh(&queue_lock);
+
+	while (buf) {
+		struct tipc_port *p_ptr;
+		struct user_port *up_ptr;
+		struct tipc_portid orig;
+		struct tipc_name_seq dseq;
+		void *usr_handle;
+		int connected;
+		int published;
+		u32 message_type;
+
+		struct sk_buff *next = buf->next;
+		struct tipc_msg *msg = buf_msg(buf);
+		u32 dref = msg_destport(msg);
+
+		message_type = msg_type(msg);
+		if (message_type > TIPC_DIRECT_MSG)
+			goto reject;	/* Unsupported message type */
+
+		p_ptr = tipc_port_lock(dref);
+		if (!p_ptr)
+			goto reject;	/* Port deleted while msg in queue */
+
+		orig.ref = msg_origport(msg);
+		orig.node = msg_orignode(msg);
+		up_ptr = p_ptr->user_port;
+		usr_handle = up_ptr->usr_handle;
+		connected = p_ptr->connected;
+		published = p_ptr->published;
+
+		if (unlikely(msg_errcode(msg)))
+			goto err;
+
+		switch (message_type) {
+
+		case TIPC_CONN_MSG:{
+				tipc_conn_msg_event cb = up_ptr->conn_msg_cb;
+				u32 peer_port = port_peerport(p_ptr);
+				u32 peer_node = port_peernode(p_ptr);
+				u32 dsz;
+
+				tipc_port_unlock(p_ptr);
+				if (unlikely(!cb))
+					goto reject;
+				if (unlikely(!connected)) {
+					if (tipc_connect2port(dref, &orig))
+						goto reject;
+				} else if ((msg_origport(msg) != peer_port) ||
+					   (msg_orignode(msg) != peer_node))
+					goto reject;
+				dsz = msg_data_sz(msg);
+				if (unlikely(dsz &&
+					     (++p_ptr->conn_unacked >=
+					      TIPC_FLOW_CONTROL_WIN)))
+					tipc_acknowledge(dref,
+							 p_ptr->conn_unacked);
+				skb_pull(buf, msg_hdr_sz(msg));
+				cb(usr_handle, dref, &buf, msg_data(msg), dsz);
+				break;
+			}
+		case TIPC_DIRECT_MSG:{
+				tipc_msg_event cb = up_ptr->msg_cb;
+
+				tipc_port_unlock(p_ptr);
+				if (unlikely(!cb || connected))
+					goto reject;
+				skb_pull(buf, msg_hdr_sz(msg));
+				cb(usr_handle, dref, &buf, msg_data(msg),
+				   msg_data_sz(msg), msg_importance(msg),
+				   &orig);
+				break;
+			}
+		case TIPC_MCAST_MSG:
+		case TIPC_NAMED_MSG:{
+				tipc_named_msg_event cb = up_ptr->named_msg_cb;
+
+				tipc_port_unlock(p_ptr);
+				if (unlikely(!cb || connected || !published))
+					goto reject;
+				dseq.type =  msg_nametype(msg);
+				dseq.lower = msg_nameinst(msg);
+				dseq.upper = (message_type == TIPC_NAMED_MSG)
+					? dseq.lower : msg_nameupper(msg);
+				skb_pull(buf, msg_hdr_sz(msg));
+				cb(usr_handle, dref, &buf, msg_data(msg),
+				   msg_data_sz(msg), msg_importance(msg),
+				   &orig, &dseq);
+				break;
+			}
+		}
+		if (buf)
+			buf_discard(buf);
+		buf = next;
+		continue;
+err:
+		switch (message_type) {
+
+		case TIPC_CONN_MSG:{
+				tipc_conn_shutdown_event cb =
+					up_ptr->conn_err_cb;
+				u32 peer_port = port_peerport(p_ptr);
+				u32 peer_node = port_peernode(p_ptr);
+
+				tipc_port_unlock(p_ptr);
+				if (!cb || !connected)
+					break;
+				if ((msg_origport(msg) != peer_port) ||
+				    (msg_orignode(msg) != peer_node))
+					break;
+				tipc_disconnect(dref);
+				skb_pull(buf, msg_hdr_sz(msg));
+				cb(usr_handle, dref, &buf, msg_data(msg),
+				   msg_data_sz(msg), msg_errcode(msg));
+				break;
+			}
+		case TIPC_DIRECT_MSG:{
+				tipc_msg_err_event cb = up_ptr->err_cb;
+
+				tipc_port_unlock(p_ptr);
+				if (!cb || connected)
+					break;
+				skb_pull(buf, msg_hdr_sz(msg));
+				cb(usr_handle, dref, &buf, msg_data(msg),
+				   msg_data_sz(msg), msg_errcode(msg), &orig);
+				break;
+			}
+		case TIPC_MCAST_MSG:
+		case TIPC_NAMED_MSG:{
+				tipc_named_msg_err_event cb =
+					up_ptr->named_err_cb;
+
+				tipc_port_unlock(p_ptr);
+				if (!cb || connected)
+					break;
+				dseq.type =  msg_nametype(msg);
+				dseq.lower = msg_nameinst(msg);
+				dseq.upper = (message_type == TIPC_NAMED_MSG)
+					? dseq.lower : msg_nameupper(msg);
+				skb_pull(buf, msg_hdr_sz(msg));
+				cb(usr_handle, dref, &buf, msg_data(msg),
+				   msg_data_sz(msg), msg_errcode(msg), &dseq);
+				break;
+			}
+		}
+		if (buf)
+			buf_discard(buf);
+		buf = next;
+		continue;
+reject:
+		tipc_reject_msg(buf, TIPC_ERR_NO_PORT);
+		buf = next;
+	}
+}
+
+/*
+ *  port_dispatcher(): Dispatcher for messages destinated
+ *  to the tipc_port interface. Called with port locked.
+ */
+
+static u32 port_dispatcher(struct tipc_port *dummy, struct sk_buff *buf)
+{
+	buf->next = NULL;
+	spin_lock_bh(&queue_lock);
+	if (msg_queue_head) {
+		msg_queue_tail->next = buf;
+		msg_queue_tail = buf;
+	} else {
+		msg_queue_tail = msg_queue_head = buf;
+		tipc_k_signal((Handler)port_dispatcher_sigh, 0);
+	}
+	spin_unlock_bh(&queue_lock);
+	return 0;
+}
+
+/*
+ * Wake up port after congestion: Called with port locked,
+ *
+ */
+
+static void port_wakeup_sh(unsigned long ref)
+{
+	struct tipc_port *p_ptr;
+	struct user_port *up_ptr;
+	tipc_continue_event cb = NULL;
+	void *uh = NULL;
+
+	p_ptr = tipc_port_lock(ref);
+	if (p_ptr) {
+		up_ptr = p_ptr->user_port;
+		if (up_ptr) {
+			cb = up_ptr->continue_event_cb;
+			uh = up_ptr->usr_handle;
+		}
+		tipc_port_unlock(p_ptr);
+	}
+	if (cb)
+		cb(uh, ref);
+}
+
+
+static void port_wakeup(struct tipc_port *p_ptr)
+{
+	tipc_k_signal((Handler)port_wakeup_sh, p_ptr->ref);
+}
+
+void tipc_acknowledge(u32 ref, u32 ack)
+{
+	struct tipc_port *p_ptr;
+	struct sk_buff *buf = NULL;
+
+	p_ptr = tipc_port_lock(ref);
+	if (!p_ptr)
+		return;
+	if (p_ptr->connected) {
+		p_ptr->conn_unacked -= ack;
+		buf = port_build_proto_msg(port_peerport(p_ptr),
+					   port_peernode(p_ptr),
+					   ref,
+					   tipc_own_addr,
+					   CONN_MANAGER,
+					   CONN_ACK,
+					   TIPC_OK,
+					   ack);
+	}
+	tipc_port_unlock(p_ptr);
+	tipc_net_route_msg(buf);
+}
+
+/*
+ * tipc_createport(): user level call.
+ */
+
+int tipc_createport(void *usr_handle,
+		    unsigned int importance,
+		    tipc_msg_err_event error_cb,
+		    tipc_named_msg_err_event named_error_cb,
+		    tipc_conn_shutdown_event conn_error_cb,
+		    tipc_msg_event msg_cb,
+		    tipc_named_msg_event named_msg_cb,
+		    tipc_conn_msg_event conn_msg_cb,
+		    tipc_continue_event continue_event_cb,/* May be zero */
+		    u32 *portref)
+{
+	struct user_port *up_ptr;
+	struct tipc_port *p_ptr;
+
+	up_ptr = kmalloc(sizeof(*up_ptr), GFP_ATOMIC);
+	if (!up_ptr) {
+		warn("Port creation failed, no memory\n");
+		return -ENOMEM;
+	}
+	p_ptr = (struct tipc_port *)tipc_createport_raw(NULL, port_dispatcher,
+						   port_wakeup, importance);
+	if (!p_ptr) {
+		kfree(up_ptr);
+		return -ENOMEM;
+	}
+
+	p_ptr->user_port = up_ptr;
+	up_ptr->usr_handle = usr_handle;
+	up_ptr->ref = p_ptr->ref;
+	up_ptr->err_cb = error_cb;
+	up_ptr->named_err_cb = named_error_cb;
+	up_ptr->conn_err_cb = conn_error_cb;
+	up_ptr->msg_cb = msg_cb;
+	up_ptr->named_msg_cb = named_msg_cb;
+	up_ptr->conn_msg_cb = conn_msg_cb;
+	up_ptr->continue_event_cb = continue_event_cb;
+	*portref = p_ptr->ref;
+	tipc_port_unlock(p_ptr);
+	return 0;
+}
+
+int tipc_portimportance(u32 ref, unsigned int *importance)
+{
+	struct tipc_port *p_ptr;
+
+	p_ptr = tipc_port_lock(ref);
+	if (!p_ptr)
+		return -EINVAL;
+	*importance = (unsigned int)msg_importance(&p_ptr->phdr);
+	tipc_port_unlock(p_ptr);
+	return 0;
+}
+
+int tipc_set_portimportance(u32 ref, unsigned int imp)
+{
+	struct tipc_port *p_ptr;
+
+	if (imp > TIPC_CRITICAL_IMPORTANCE)
+		return -EINVAL;
+
+	p_ptr = tipc_port_lock(ref);
+	if (!p_ptr)
+		return -EINVAL;
+	msg_set_importance(&p_ptr->phdr, (u32)imp);
+	tipc_port_unlock(p_ptr);
+	return 0;
+}
+
+
+int tipc_publish(u32 ref, unsigned int scope, struct tipc_name_seq const *seq)
+{
+	struct tipc_port *p_ptr;
+	struct publication *publ;
+	u32 key;
+	int res = -EINVAL;
+
+	p_ptr = tipc_port_lock(ref);
+	if (!p_ptr)
+		return -EINVAL;
+
+	if (p_ptr->connected)
+		goto exit;
+	if (seq->lower > seq->upper)
+		goto exit;
+	if ((scope < TIPC_ZONE_SCOPE) || (scope > TIPC_NODE_SCOPE))
+		goto exit;
+	key = ref + p_ptr->pub_count + 1;
+	if (key == ref) {
+		res = -EADDRINUSE;
+		goto exit;
+	}
+	publ = tipc_nametbl_publish(seq->type, seq->lower, seq->upper,
+				    scope, p_ptr->ref, key);
+	if (publ) {
+		list_add(&publ->pport_list, &p_ptr->publications);
+		p_ptr->pub_count++;
+		p_ptr->published = 1;
+		res = 0;
+	}
+exit:
+	tipc_port_unlock(p_ptr);
+	return res;
+}
+
+int tipc_withdraw(u32 ref, unsigned int scope, struct tipc_name_seq const *seq)
+{
+	struct tipc_port *p_ptr;
+	struct publication *publ;
+	struct publication *tpubl;
+	int res = -EINVAL;
+
+	p_ptr = tipc_port_lock(ref);
+	if (!p_ptr)
+		return -EINVAL;
+	if (!seq) {
+		list_for_each_entry_safe(publ, tpubl,
+					 &p_ptr->publications, pport_list) {
+			tipc_nametbl_withdraw(publ->type, publ->lower,
+					      publ->ref, publ->key);
+		}
+		res = 0;
+	} else {
+		list_for_each_entry_safe(publ, tpubl,
+					 &p_ptr->publications, pport_list) {
+			if (publ->scope != scope)
+				continue;
+			if (publ->type != seq->type)
+				continue;
+			if (publ->lower != seq->lower)
+				continue;
+			if (publ->upper != seq->upper)
+				break;
+			tipc_nametbl_withdraw(publ->type, publ->lower,
+					      publ->ref, publ->key);
+			res = 0;
+			break;
+		}
+	}
+	if (list_empty(&p_ptr->publications))
+		p_ptr->published = 0;
+	tipc_port_unlock(p_ptr);
+	return res;
+}
+
+int tipc_connect2port(u32 ref, struct tipc_portid const *peer)
+{
+	struct tipc_port *p_ptr;
+	struct tipc_msg *msg;
+	int res = -EINVAL;
+
+	p_ptr = tipc_port_lock(ref);
+	if (!p_ptr)
+		return -EINVAL;
+	if (p_ptr->published || p_ptr->connected)
+		goto exit;
+	if (!peer->ref)
+		goto exit;
+
+	msg = &p_ptr->phdr;
+	msg_set_destnode(msg, peer->node);
+	msg_set_destport(msg, peer->ref);
+	msg_set_orignode(msg, tipc_own_addr);
+	msg_set_origport(msg, p_ptr->ref);
+	msg_set_type(msg, TIPC_CONN_MSG);
+	msg_set_lookup_scope(msg, 0);
+	msg_set_hdr_sz(msg, SHORT_H_SIZE);
+
+	p_ptr->probing_interval = PROBING_INTERVAL;
+	p_ptr->probing_state = CONFIRMED;
+	p_ptr->connected = 1;
+	k_start_timer(&p_ptr->timer, p_ptr->probing_interval);
+
+	tipc_nodesub_subscribe(&p_ptr->subscription, peer->node,
+			  (void *)(unsigned long)ref,
+			  (net_ev_handler)port_handle_node_down);
+	res = 0;
+exit:
+	tipc_port_unlock(p_ptr);
+	p_ptr->max_pkt = tipc_link_get_max_pkt(peer->node, ref);
+	return res;
+}
+
+/**
+ * tipc_disconnect_port - disconnect port from peer
+ *
+ * Port must be locked.
+ */
+
+int tipc_disconnect_port(struct tipc_port *tp_ptr)
+{
+	int res;
+
+	if (tp_ptr->connected) {
+		tp_ptr->connected = 0;
+		/* let timer expire on it's own to avoid deadlock! */
+		tipc_nodesub_unsubscribe(
+			&((struct tipc_port *)tp_ptr)->subscription);
+		res = 0;
+	} else {
+		res = -ENOTCONN;
+	}
+	return res;
+}
+
+/*
+ * tipc_disconnect(): Disconnect port form peer.
+ *                    This is a node local operation.
+ */
+
+int tipc_disconnect(u32 ref)
+{
+	struct tipc_port *p_ptr;
+	int res;
+
+	p_ptr = tipc_port_lock(ref);
+	if (!p_ptr)
+		return -EINVAL;
+	res = tipc_disconnect_port((struct tipc_port *)p_ptr);
+	tipc_port_unlock(p_ptr);
+	return res;
+}
+
+/*
+ * tipc_shutdown(): Send a SHUTDOWN msg to peer and disconnect
+ */
+int tipc_shutdown(u32 ref)
+{
+	struct tipc_port *p_ptr;
+	struct sk_buff *buf = NULL;
+
+	p_ptr = tipc_port_lock(ref);
+	if (!p_ptr)
+		return -EINVAL;
+
+	if (p_ptr->connected) {
+		u32 imp = msg_importance(&p_ptr->phdr);
+		if (imp < TIPC_CRITICAL_IMPORTANCE)
+			imp++;
+		buf = port_build_proto_msg(port_peerport(p_ptr),
+					   port_peernode(p_ptr),
+					   ref,
+					   tipc_own_addr,
+					   imp,
+					   TIPC_CONN_MSG,
+					   TIPC_CONN_SHUTDOWN,
+					   0);
+	}
+	tipc_port_unlock(p_ptr);
+	tipc_net_route_msg(buf);
+	return tipc_disconnect(ref);
+}
+
+/*
+ *  tipc_port_recv_sections(): Concatenate and deliver sectioned
+ *                        message for this node.
+ */
+
+static int tipc_port_recv_sections(struct tipc_port *sender, unsigned int num_sect,
+				   struct iovec const *msg_sect,
+				   unsigned int total_len)
+{
+	struct sk_buff *buf;
+	int res;
+
+	res = tipc_msg_build(&sender->phdr, msg_sect, num_sect, total_len,
+			MAX_MSG_SIZE, !sender->user_port, &buf);
+	if (likely(buf))
+		tipc_port_recv_msg(buf);
+	return res;
+}
+
+/**
+ * tipc_send - send message sections on connection
+ */
+
+int tipc_send(u32 ref, unsigned int num_sect, struct iovec const *msg_sect,
+	      unsigned int total_len)
+{
+	struct tipc_port *p_ptr;
+	u32 destnode;
+	int res;
+
+	p_ptr = tipc_port_deref(ref);
+	if (!p_ptr || !p_ptr->connected)
+		return -EINVAL;
+
+	p_ptr->congested = 1;
+	if (!tipc_port_congested(p_ptr)) {
+		destnode = port_peernode(p_ptr);
+		if (likely(destnode != tipc_own_addr))
+			res = tipc_link_send_sections_fast(p_ptr, msg_sect, num_sect,
+							   total_len, destnode);
+		else
+			res = tipc_port_recv_sections(p_ptr, num_sect, msg_sect,
+						      total_len);
+
+		if (likely(res != -ELINKCONG)) {
+			p_ptr->congested = 0;
+			if (res > 0)
+				p_ptr->sent++;
+			return res;
+		}
+	}
+	if (port_unreliable(p_ptr)) {
+		p_ptr->congested = 0;
+		return total_len;
+	}
+	return -ELINKCONG;
+}
+
+/**
+ * tipc_send2name - send message sections to port name
+ */
+
+int tipc_send2name(u32 ref, struct tipc_name const *name, unsigned int domain,
+		   unsigned int num_sect, struct iovec const *msg_sect,
+		   unsigned int total_len)
+{
+	struct tipc_port *p_ptr;
+	struct tipc_msg *msg;
+	u32 destnode = domain;
+	u32 destport;
+	int res;
+
+	p_ptr = tipc_port_deref(ref);
+	if (!p_ptr || p_ptr->connected)
+		return -EINVAL;
+
+	msg = &p_ptr->phdr;
+	msg_set_type(msg, TIPC_NAMED_MSG);
+	msg_set_orignode(msg, tipc_own_addr);
+	msg_set_origport(msg, ref);
+	msg_set_hdr_sz(msg, LONG_H_SIZE);
+	msg_set_nametype(msg, name->type);
+	msg_set_nameinst(msg, name->instance);
+	msg_set_lookup_scope(msg, tipc_addr_scope(domain));
+	destport = tipc_nametbl_translate(name->type, name->instance, &destnode);
+	msg_set_destnode(msg, destnode);
+	msg_set_destport(msg, destport);
+
+	if (likely(destport)) {
+		if (likely(destnode == tipc_own_addr))
+			res = tipc_port_recv_sections(p_ptr, num_sect,
+						      msg_sect, total_len);
+		else
+			res = tipc_link_send_sections_fast(p_ptr, msg_sect,
+							   num_sect, total_len,
+							   destnode);
+		if (likely(res != -ELINKCONG)) {
+			if (res > 0)
+				p_ptr->sent++;
+			return res;
+		}
+		if (port_unreliable(p_ptr)) {
+			return total_len;
+		}
+		return -ELINKCONG;
+	}
+	return tipc_port_reject_sections(p_ptr, msg, msg_sect, num_sect,
+					 total_len, TIPC_ERR_NO_NAME);
+}
+
+/**
+ * tipc_send2port - send message sections to port identity
+ */
+
+int tipc_send2port(u32 ref, struct tipc_portid const *dest,
+		   unsigned int num_sect, struct iovec const *msg_sect,
+		   unsigned int total_len)
+{
+	struct tipc_port *p_ptr;
+	struct tipc_msg *msg;
+	int res;
+
+	p_ptr = tipc_port_deref(ref);
+	if (!p_ptr || p_ptr->connected)
+		return -EINVAL;
+
+	msg = &p_ptr->phdr;
+	msg_set_type(msg, TIPC_DIRECT_MSG);
+	msg_set_lookup_scope(msg, 0);
+	msg_set_orignode(msg, tipc_own_addr);
+	msg_set_origport(msg, ref);
+	msg_set_destnode(msg, dest->node);
+	msg_set_destport(msg, dest->ref);
+	msg_set_hdr_sz(msg, DIR_MSG_H_SIZE);
+
+	if (dest->node == tipc_own_addr)
+		res =  tipc_port_recv_sections(p_ptr, num_sect, msg_sect,
+					       total_len);
+	else
+		res = tipc_link_send_sections_fast(p_ptr, msg_sect, num_sect,
+						   total_len, dest->node);
+	if (likely(res != -ELINKCONG)) {
+		if (res > 0)
+			p_ptr->sent++;
+		return res;
+	}
+	if (port_unreliable(p_ptr)) {
+		return total_len;
+	}
+	return -ELINKCONG;
+}
+
+/**
+ * tipc_send_buf2port - send message buffer to port identity
+ */
+
+int tipc_send_buf2port(u32 ref, struct tipc_portid const *dest,
+	       struct sk_buff *buf, unsigned int dsz)
+{
+	struct tipc_port *p_ptr;
+	struct tipc_msg *msg;
+	int res;
+
+	p_ptr = (struct tipc_port *)tipc_ref_deref(ref);
+	if (!p_ptr || p_ptr->connected)
+		return -EINVAL;
+
+	msg = &p_ptr->phdr;
+	msg_set_type(msg, TIPC_DIRECT_MSG);
+	msg_set_orignode(msg, tipc_own_addr);
+	msg_set_origport(msg, ref);
+	msg_set_destnode(msg, dest->node);
+	msg_set_destport(msg, dest->ref);
+	msg_set_hdr_sz(msg, DIR_MSG_H_SIZE);
+	msg_set_size(msg, DIR_MSG_H_SIZE + dsz);
+	if (skb_cow(buf, DIR_MSG_H_SIZE))
+		return -ENOMEM;
+
+	skb_push(buf, DIR_MSG_H_SIZE);
+	skb_copy_to_linear_data(buf, msg, DIR_MSG_H_SIZE);
+
+	if (dest->node == tipc_own_addr)
+		res = tipc_port_recv_msg(buf);
+	else
+		res = tipc_send_buf_fast(buf, dest->node);
+	if (likely(res != -ELINKCONG)) {
+		if (res > 0)
+			p_ptr->sent++;
+		return res;
+	}
+	if (port_unreliable(p_ptr))
+		return dsz;
+	return -ELINKCONG;
+}
+