Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 955 insertions, 0 deletions

diff --git a/net/tipc/group.c b/net/tipc/group.c
new file mode 100644
index 000000000..b656385ef
--- /dev/null
+++ b/net/tipc/group.c
@@ -0,0 +1,955 @@
+/*
+ * net/tipc/group.c: TIPC group messaging code
+ *
+ * Copyright (c) 2017, Ericsson AB
+ * 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 "addr.h"
+#include "group.h"
+#include "bcast.h"
+#include "topsrv.h"
+#include "msg.h"
+#include "socket.h"
+#include "node.h"
+#include "name_table.h"
+#include "subscr.h"
+
+#define ADV_UNIT (((MAX_MSG_SIZE + MAX_H_SIZE) / FLOWCTL_BLK_SZ) + 1)
+#define ADV_IDLE ADV_UNIT
+#define ADV_ACTIVE (ADV_UNIT * 12)
+
+enum mbr_state {
+	MBR_JOINING,
+	MBR_PUBLISHED,
+	MBR_JOINED,
+	MBR_PENDING,
+	MBR_ACTIVE,
+	MBR_RECLAIMING,
+	MBR_REMITTED,
+	MBR_LEAVING
+};
+
+struct tipc_member {
+	struct rb_node tree_node;
+	struct list_head list;
+	struct list_head small_win;
+	struct sk_buff_head deferredq;
+	struct tipc_group *group;
+	u32 node;
+	u32 port;
+	u32 instance;
+	enum mbr_state state;
+	u16 advertised;
+	u16 window;
+	u16 bc_rcv_nxt;
+	u16 bc_syncpt;
+	u16 bc_acked;
+};
+
+struct tipc_group {
+	struct rb_root members;
+	struct list_head small_win;
+	struct list_head pending;
+	struct list_head active;
+	struct tipc_nlist dests;
+	struct net *net;
+	int subid;
+	u32 type;
+	u32 instance;
+	u32 scope;
+	u32 portid;
+	u16 member_cnt;
+	u16 active_cnt;
+	u16 max_active;
+	u16 bc_snd_nxt;
+	u16 bc_ackers;
+	bool *open;
+	bool loopback;
+	bool events;
+};
+
+static void tipc_group_proto_xmit(struct tipc_group *grp, struct tipc_member *m,
+				  int mtyp, struct sk_buff_head *xmitq);
+
+static void tipc_group_open(struct tipc_member *m, bool *wakeup)
+{
+	*wakeup = false;
+	if (list_empty(&m->small_win))
+		return;
+	list_del_init(&m->small_win);
+	*m->group->open = true;
+	*wakeup = true;
+}
+
+static void tipc_group_decr_active(struct tipc_group *grp,
+				   struct tipc_member *m)
+{
+	if (m->state == MBR_ACTIVE || m->state == MBR_RECLAIMING ||
+	    m->state == MBR_REMITTED)
+		grp->active_cnt--;
+}
+
+static int tipc_group_rcvbuf_limit(struct tipc_group *grp)
+{
+	int max_active, active_pool, idle_pool;
+	int mcnt = grp->member_cnt + 1;
+
+	/* Limit simultaneous reception from other members */
+	max_active = min(mcnt / 8, 64);
+	max_active = max(max_active, 16);
+	grp->max_active = max_active;
+
+	/* Reserve blocks for active and idle members */
+	active_pool = max_active * ADV_ACTIVE;
+	idle_pool = (mcnt - max_active) * ADV_IDLE;
+
+	/* Scale to bytes, considering worst-case truesize/msgsize ratio */
+	return (active_pool + idle_pool) * FLOWCTL_BLK_SZ * 4;
+}
+
+u16 tipc_group_bc_snd_nxt(struct tipc_group *grp)
+{
+	return grp->bc_snd_nxt;
+}
+
+static bool tipc_group_is_receiver(struct tipc_member *m)
+{
+	return m && m->state != MBR_JOINING && m->state != MBR_LEAVING;
+}
+
+static bool tipc_group_is_sender(struct tipc_member *m)
+{
+	return m && m->state != MBR_JOINING && m->state != MBR_PUBLISHED;
+}
+
+u32 tipc_group_exclude(struct tipc_group *grp)
+{
+	if (!grp->loopback)
+		return grp->portid;
+	return 0;
+}
+
+struct tipc_group *tipc_group_create(struct net *net, u32 portid,
+				     struct tipc_group_req *mreq,
+				     bool *group_is_open)
+{
+	u32 filter = TIPC_SUB_PORTS | TIPC_SUB_NO_STATUS;
+	bool global = mreq->scope != TIPC_NODE_SCOPE;
+	struct tipc_group *grp;
+	u32 type = mreq->type;
+
+	grp = kzalloc(sizeof(*grp), GFP_ATOMIC);
+	if (!grp)
+		return NULL;
+	tipc_nlist_init(&grp->dests, tipc_own_addr(net));
+	INIT_LIST_HEAD(&grp->small_win);
+	INIT_LIST_HEAD(&grp->active);
+	INIT_LIST_HEAD(&grp->pending);
+	grp->members = RB_ROOT;
+	grp->net = net;
+	grp->portid = portid;
+	grp->type = type;
+	grp->instance = mreq->instance;
+	grp->scope = mreq->scope;
+	grp->loopback = mreq->flags & TIPC_GROUP_LOOPBACK;
+	grp->events = mreq->flags & TIPC_GROUP_MEMBER_EVTS;
+	grp->open = group_is_open;
+	*grp->open = false;
+	filter |= global ? TIPC_SUB_CLUSTER_SCOPE : TIPC_SUB_NODE_SCOPE;
+	if (tipc_topsrv_kern_subscr(net, portid, type, 0, ~0,
+				    filter, &grp->subid))
+		return grp;
+	kfree(grp);
+	return NULL;
+}
+
+void tipc_group_join(struct net *net, struct tipc_group *grp, int *sk_rcvbuf)
+{
+	struct rb_root *tree = &grp->members;
+	struct tipc_member *m, *tmp;
+	struct sk_buff_head xmitq;
+
+	__skb_queue_head_init(&xmitq);
+	rbtree_postorder_for_each_entry_safe(m, tmp, tree, tree_node) {
+		tipc_group_proto_xmit(grp, m, GRP_JOIN_MSG, &xmitq);
+		tipc_group_update_member(m, 0);
+	}
+	tipc_node_distr_xmit(net, &xmitq);
+	*sk_rcvbuf = tipc_group_rcvbuf_limit(grp);
+}
+
+void tipc_group_delete(struct net *net, struct tipc_group *grp)
+{
+	struct rb_root *tree = &grp->members;
+	struct tipc_member *m, *tmp;
+	struct sk_buff_head xmitq;
+
+	__skb_queue_head_init(&xmitq);
+
+	rbtree_postorder_for_each_entry_safe(m, tmp, tree, tree_node) {
+		tipc_group_proto_xmit(grp, m, GRP_LEAVE_MSG, &xmitq);
+		__skb_queue_purge(&m->deferredq);
+		list_del(&m->list);
+		kfree(m);
+	}
+	tipc_node_distr_xmit(net, &xmitq);
+	tipc_nlist_purge(&grp->dests);
+	tipc_topsrv_kern_unsubscr(net, grp->subid);
+	kfree(grp);
+}
+
+static struct tipc_member *tipc_group_find_member(struct tipc_group *grp,
+						  u32 node, u32 port)
+{
+	struct rb_node *n = grp->members.rb_node;
+	u64 nkey, key = (u64)node << 32 | port;
+	struct tipc_member *m;
+
+	while (n) {
+		m = container_of(n, struct tipc_member, tree_node);
+		nkey = (u64)m->node << 32 | m->port;
+		if (key < nkey)
+			n = n->rb_left;
+		else if (key > nkey)
+			n = n->rb_right;
+		else
+			return m;
+	}
+	return NULL;
+}
+
+static struct tipc_member *tipc_group_find_dest(struct tipc_group *grp,
+						u32 node, u32 port)
+{
+	struct tipc_member *m;
+
+	m = tipc_group_find_member(grp, node, port);
+	if (m && tipc_group_is_receiver(m))
+		return m;
+	return NULL;
+}
+
+static struct tipc_member *tipc_group_find_node(struct tipc_group *grp,
+						u32 node)
+{
+	struct tipc_member *m;
+	struct rb_node *n;
+
+	for (n = rb_first(&grp->members); n; n = rb_next(n)) {
+		m = container_of(n, struct tipc_member, tree_node);
+		if (m->node == node)
+			return m;
+	}
+	return NULL;
+}
+
+static int tipc_group_add_to_tree(struct tipc_group *grp,
+				  struct tipc_member *m)
+{
+	u64 nkey, key = (u64)m->node << 32 | m->port;
+	struct rb_node **n, *parent = NULL;
+	struct tipc_member *tmp;
+
+	n = &grp->members.rb_node;
+	while (*n) {
+		tmp = container_of(*n, struct tipc_member, tree_node);
+		parent = *n;
+		tmp = container_of(parent, struct tipc_member, tree_node);
+		nkey = (u64)tmp->node << 32 | tmp->port;
+		if (key < nkey)
+			n = &(*n)->rb_left;
+		else if (key > nkey)
+			n = &(*n)->rb_right;
+		else
+			return -EEXIST;
+	}
+	rb_link_node(&m->tree_node, parent, n);
+	rb_insert_color(&m->tree_node, &grp->members);
+	return 0;
+}
+
+static struct tipc_member *tipc_group_create_member(struct tipc_group *grp,
+						    u32 node, u32 port,
+						    u32 instance, int state)
+{
+	struct tipc_member *m;
+	int ret;
+
+	m = kzalloc(sizeof(*m), GFP_ATOMIC);
+	if (!m)
+		return NULL;
+	INIT_LIST_HEAD(&m->list);
+	INIT_LIST_HEAD(&m->small_win);
+	__skb_queue_head_init(&m->deferredq);
+	m->group = grp;
+	m->node = node;
+	m->port = port;
+	m->instance = instance;
+	m->bc_acked = grp->bc_snd_nxt - 1;
+	ret = tipc_group_add_to_tree(grp, m);
+	if (ret < 0) {
+		kfree(m);
+		return NULL;
+	}
+	grp->member_cnt++;
+	tipc_nlist_add(&grp->dests, m->node);
+	m->state = state;
+	return m;
+}
+
+void tipc_group_add_member(struct tipc_group *grp, u32 node,
+			   u32 port, u32 instance)
+{
+	tipc_group_create_member(grp, node, port, instance, MBR_PUBLISHED);
+}
+
+static void tipc_group_delete_member(struct tipc_group *grp,
+				     struct tipc_member *m)
+{
+	rb_erase(&m->tree_node, &grp->members);
+	grp->member_cnt--;
+
+	/* Check if we were waiting for replicast ack from this member */
+	if (grp->bc_ackers && less(m->bc_acked, grp->bc_snd_nxt - 1))
+		grp->bc_ackers--;
+
+	list_del_init(&m->list);
+	list_del_init(&m->small_win);
+	tipc_group_decr_active(grp, m);
+
+	/* If last member on a node, remove node from dest list */
+	if (!tipc_group_find_node(grp, m->node))
+		tipc_nlist_del(&grp->dests, m->node);
+
+	kfree(m);
+}
+
+struct tipc_nlist *tipc_group_dests(struct tipc_group *grp)
+{
+	return &grp->dests;
+}
+
+void tipc_group_self(struct tipc_group *grp, struct tipc_name_seq *seq,
+		     int *scope)
+{
+	seq->type = grp->type;
+	seq->lower = grp->instance;
+	seq->upper = grp->instance;
+	*scope = grp->scope;
+}
+
+void tipc_group_update_member(struct tipc_member *m, int len)
+{
+	struct tipc_group *grp = m->group;
+	struct tipc_member *_m, *tmp;
+
+	if (!tipc_group_is_receiver(m))
+		return;
+
+	m->window -= len;
+
+	if (m->window >= ADV_IDLE)
+		return;
+
+	list_del_init(&m->small_win);
+
+	/* Sort member into small_window members' list */
+	list_for_each_entry_safe(_m, tmp, &grp->small_win, small_win) {
+		if (_m->window > m->window)
+			break;
+	}
+	list_add_tail(&m->small_win, &_m->small_win);
+}
+
+void tipc_group_update_bc_members(struct tipc_group *grp, int len, bool ack)
+{
+	u16 prev = grp->bc_snd_nxt - 1;
+	struct tipc_member *m;
+	struct rb_node *n;
+	u16 ackers = 0;
+
+	for (n = rb_first(&grp->members); n; n = rb_next(n)) {
+		m = container_of(n, struct tipc_member, tree_node);
+		if (tipc_group_is_receiver(m)) {
+			tipc_group_update_member(m, len);
+			m->bc_acked = prev;
+			ackers++;
+		}
+	}
+
+	/* Mark number of acknowledges to expect, if any */
+	if (ack)
+		grp->bc_ackers = ackers;
+	grp->bc_snd_nxt++;
+}
+
+bool tipc_group_cong(struct tipc_group *grp, u32 dnode, u32 dport,
+		     int len, struct tipc_member **mbr)
+{
+	struct sk_buff_head xmitq;
+	struct tipc_member *m;
+	int adv, state;
+
+	m = tipc_group_find_dest(grp, dnode, dport);
+	if (!tipc_group_is_receiver(m)) {
+		*mbr = NULL;
+		return false;
+	}
+	*mbr = m;
+
+	if (m->window >= len)
+		return false;
+
+	*grp->open = false;
+
+	/* If not fully advertised, do it now to prevent mutual blocking */
+	adv = m->advertised;
+	state = m->state;
+	if (state == MBR_JOINED && adv == ADV_IDLE)
+		return true;
+	if (state == MBR_ACTIVE && adv == ADV_ACTIVE)
+		return true;
+	if (state == MBR_PENDING && adv == ADV_IDLE)
+		return true;
+	__skb_queue_head_init(&xmitq);
+	tipc_group_proto_xmit(grp, m, GRP_ADV_MSG, &xmitq);
+	tipc_node_distr_xmit(grp->net, &xmitq);
+	return true;
+}
+
+bool tipc_group_bc_cong(struct tipc_group *grp, int len)
+{
+	struct tipc_member *m = NULL;
+
+	/* If prev bcast was replicast, reject until all receivers have acked */
+	if (grp->bc_ackers) {
+		*grp->open = false;
+		return true;
+	}
+	if (list_empty(&grp->small_win))
+		return false;
+
+	m = list_first_entry(&grp->small_win, struct tipc_member, small_win);
+	if (m->window >= len)
+		return false;
+
+	return tipc_group_cong(grp, m->node, m->port, len, &m);
+}
+
+/* tipc_group_sort_msg() - sort msg into queue by bcast sequence number
+ */
+static void tipc_group_sort_msg(struct sk_buff *skb, struct sk_buff_head *defq)
+{
+	struct tipc_msg *_hdr, *hdr = buf_msg(skb);
+	u16 bc_seqno = msg_grp_bc_seqno(hdr);
+	struct sk_buff *_skb, *tmp;
+	int mtyp = msg_type(hdr);
+
+	/* Bcast/mcast may be bypassed by ucast or other bcast, - sort it in */
+	if (mtyp == TIPC_GRP_BCAST_MSG || mtyp == TIPC_GRP_MCAST_MSG) {
+		skb_queue_walk_safe(defq, _skb, tmp) {
+			_hdr = buf_msg(_skb);
+			if (!less(bc_seqno, msg_grp_bc_seqno(_hdr)))
+				continue;
+			__skb_queue_before(defq, _skb, skb);
+			return;
+		}
+		/* Bcast was not bypassed, - add to tail */
+	}
+	/* Unicasts are never bypassed, - always add to tail */
+	__skb_queue_tail(defq, skb);
+}
+
+/* tipc_group_filter_msg() - determine if we should accept arriving message
+ */
+void tipc_group_filter_msg(struct tipc_group *grp, struct sk_buff_head *inputq,
+			   struct sk_buff_head *xmitq)
+{
+	struct sk_buff *skb = __skb_dequeue(inputq);
+	bool ack, deliver, update, leave = false;
+	struct sk_buff_head *defq;
+	struct tipc_member *m;
+	struct tipc_msg *hdr;
+	u32 node, port;
+	int mtyp, blks;
+
+	if (!skb)
+		return;
+
+	hdr = buf_msg(skb);
+	node =  msg_orignode(hdr);
+	port = msg_origport(hdr);
+
+	if (!msg_in_group(hdr))
+		goto drop;
+
+	m = tipc_group_find_member(grp, node, port);
+	if (!tipc_group_is_sender(m))
+		goto drop;
+
+	if (less(msg_grp_bc_seqno(hdr), m->bc_rcv_nxt))
+		goto drop;
+
+	TIPC_SKB_CB(skb)->orig_member = m->instance;
+	defq = &m->deferredq;
+	tipc_group_sort_msg(skb, defq);
+
+	while ((skb = skb_peek(defq))) {
+		hdr = buf_msg(skb);
+		mtyp = msg_type(hdr);
+		blks = msg_blocks(hdr);
+		deliver = true;
+		ack = false;
+		update = false;
+
+		if (more(msg_grp_bc_seqno(hdr), m->bc_rcv_nxt))
+			break;
+
+		/* Decide what to do with message */
+		switch (mtyp) {
+		case TIPC_GRP_MCAST_MSG:
+			if (msg_nameinst(hdr) != grp->instance) {
+				update = true;
+				deliver = false;
+			}
+			/* Fall thru */
+		case TIPC_GRP_BCAST_MSG:
+			m->bc_rcv_nxt++;
+			ack = msg_grp_bc_ack_req(hdr);
+			break;
+		case TIPC_GRP_UCAST_MSG:
+			break;
+		case TIPC_GRP_MEMBER_EVT:
+			if (m->state == MBR_LEAVING)
+				leave = true;
+			if (!grp->events)
+				deliver = false;
+			break;
+		default:
+			break;
+		}
+
+		/* Execute decisions */
+		__skb_dequeue(defq);
+		if (deliver)
+			__skb_queue_tail(inputq, skb);
+		else
+			kfree_skb(skb);
+
+		if (ack)
+			tipc_group_proto_xmit(grp, m, GRP_ACK_MSG, xmitq);
+
+		if (leave) {
+			__skb_queue_purge(defq);
+			tipc_group_delete_member(grp, m);
+			break;
+		}
+		if (!update)
+			continue;
+
+		tipc_group_update_rcv_win(grp, blks, node, port, xmitq);
+	}
+	return;
+drop:
+	kfree_skb(skb);
+}
+
+void tipc_group_update_rcv_win(struct tipc_group *grp, int blks, u32 node,
+			       u32 port, struct sk_buff_head *xmitq)
+{
+	struct list_head *active = &grp->active;
+	int max_active = grp->max_active;
+	int reclaim_limit = max_active * 3 / 4;
+	int active_cnt = grp->active_cnt;
+	struct tipc_member *m, *rm, *pm;
+
+	m = tipc_group_find_member(grp, node, port);
+	if (!m)
+		return;
+
+	m->advertised -= blks;
+
+	switch (m->state) {
+	case MBR_JOINED:
+		/* First, decide if member can go active */
+		if (active_cnt <= max_active) {
+			m->state = MBR_ACTIVE;
+			list_add_tail(&m->list, active);
+			grp->active_cnt++;
+			tipc_group_proto_xmit(grp, m, GRP_ADV_MSG, xmitq);
+		} else {
+			m->state = MBR_PENDING;
+			list_add_tail(&m->list, &grp->pending);
+		}
+
+		if (active_cnt < reclaim_limit)
+			break;
+
+		/* Reclaim from oldest active member, if possible */
+		if (!list_empty(active)) {
+			rm = list_first_entry(active, struct tipc_member, list);
+			rm->state = MBR_RECLAIMING;
+			list_del_init(&rm->list);
+			tipc_group_proto_xmit(grp, rm, GRP_RECLAIM_MSG, xmitq);
+			break;
+		}
+		/* Nobody to reclaim from; - revert oldest pending to JOINED */
+		pm = list_first_entry(&grp->pending, struct tipc_member, list);
+		list_del_init(&pm->list);
+		pm->state = MBR_JOINED;
+		tipc_group_proto_xmit(grp, pm, GRP_ADV_MSG, xmitq);
+		break;
+	case MBR_ACTIVE:
+		if (!list_is_last(&m->list, &grp->active))
+			list_move_tail(&m->list, &grp->active);
+		if (m->advertised > (ADV_ACTIVE * 3 / 4))
+			break;
+		tipc_group_proto_xmit(grp, m, GRP_ADV_MSG, xmitq);
+		break;
+	case MBR_REMITTED:
+		if (m->advertised > ADV_IDLE)
+			break;
+		m->state = MBR_JOINED;
+		grp->active_cnt--;
+		if (m->advertised < ADV_IDLE) {
+			pr_warn_ratelimited("Rcv unexpected msg after REMIT\n");
+			tipc_group_proto_xmit(grp, m, GRP_ADV_MSG, xmitq);
+		}
+
+		if (list_empty(&grp->pending))
+			return;
+
+		/* Set oldest pending member to active and advertise */
+		pm = list_first_entry(&grp->pending, struct tipc_member, list);
+		pm->state = MBR_ACTIVE;
+		list_move_tail(&pm->list, &grp->active);
+		grp->active_cnt++;
+		tipc_group_proto_xmit(grp, pm, GRP_ADV_MSG, xmitq);
+		break;
+	case MBR_RECLAIMING:
+	case MBR_JOINING:
+	case MBR_LEAVING:
+	default:
+		break;
+	}
+}
+
+static void tipc_group_create_event(struct tipc_group *grp,
+				    struct tipc_member *m,
+				    u32 event, u16 seqno,
+				    struct sk_buff_head *inputq)
+{	u32 dnode = tipc_own_addr(grp->net);
+	struct tipc_event evt;
+	struct sk_buff *skb;
+	struct tipc_msg *hdr;
+
+	memset(&evt, 0, sizeof(evt));
+	evt.event = event;
+	evt.found_lower = m->instance;
+	evt.found_upper = m->instance;
+	evt.port.ref = m->port;
+	evt.port.node = m->node;
+	evt.s.seq.type = grp->type;
+	evt.s.seq.lower = m->instance;
+	evt.s.seq.upper = m->instance;
+
+	skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE, TIPC_GRP_MEMBER_EVT,
+			      GROUP_H_SIZE, sizeof(evt), dnode, m->node,
+			      grp->portid, m->port, 0);
+	if (!skb)
+		return;
+
+	hdr = buf_msg(skb);
+	msg_set_nametype(hdr, grp->type);
+	msg_set_grp_evt(hdr, event);
+	msg_set_dest_droppable(hdr, true);
+	msg_set_grp_bc_seqno(hdr, seqno);
+	memcpy(msg_data(hdr), &evt, sizeof(evt));
+	TIPC_SKB_CB(skb)->orig_member = m->instance;
+	__skb_queue_tail(inputq, skb);
+}
+
+static void tipc_group_proto_xmit(struct tipc_group *grp, struct tipc_member *m,
+				  int mtyp, struct sk_buff_head *xmitq)
+{
+	struct tipc_msg *hdr;
+	struct sk_buff *skb;
+	int adv = 0;
+
+	skb = tipc_msg_create(GROUP_PROTOCOL, mtyp, INT_H_SIZE, 0,
+			      m->node, tipc_own_addr(grp->net),
+			      m->port, grp->portid, 0);
+	if (!skb)
+		return;
+
+	if (m->state == MBR_ACTIVE)
+		adv = ADV_ACTIVE - m->advertised;
+	else if (m->state == MBR_JOINED || m->state == MBR_PENDING)
+		adv = ADV_IDLE - m->advertised;
+
+	hdr = buf_msg(skb);
+
+	if (mtyp == GRP_JOIN_MSG) {
+		msg_set_grp_bc_syncpt(hdr, grp->bc_snd_nxt);
+		msg_set_adv_win(hdr, adv);
+		m->advertised += adv;
+	} else if (mtyp == GRP_LEAVE_MSG) {
+		msg_set_grp_bc_syncpt(hdr, grp->bc_snd_nxt);
+	} else if (mtyp == GRP_ADV_MSG) {
+		msg_set_adv_win(hdr, adv);
+		m->advertised += adv;
+	} else if (mtyp == GRP_ACK_MSG) {
+		msg_set_grp_bc_acked(hdr, m->bc_rcv_nxt);
+	} else if (mtyp == GRP_REMIT_MSG) {
+		msg_set_grp_remitted(hdr, m->window);
+	}
+	msg_set_dest_droppable(hdr, true);
+	__skb_queue_tail(xmitq, skb);
+}
+
+void tipc_group_proto_rcv(struct tipc_group *grp, bool *usr_wakeup,
+			  struct tipc_msg *hdr, struct sk_buff_head *inputq,
+			  struct sk_buff_head *xmitq)
+{
+	u32 node = msg_orignode(hdr);
+	u32 port = msg_origport(hdr);
+	struct tipc_member *m, *pm;
+	u16 remitted, in_flight;
+
+	if (!grp)
+		return;
+
+	if (grp->scope == TIPC_NODE_SCOPE && node != tipc_own_addr(grp->net))
+		return;
+
+	m = tipc_group_find_member(grp, node, port);
+
+	switch (msg_type(hdr)) {
+	case GRP_JOIN_MSG:
+		if (!m)
+			m = tipc_group_create_member(grp, node, port,
+						     0, MBR_JOINING);
+		if (!m)
+			return;
+		m->bc_syncpt = msg_grp_bc_syncpt(hdr);
+		m->bc_rcv_nxt = m->bc_syncpt;
+		m->window += msg_adv_win(hdr);
+
+		/* Wait until PUBLISH event is received if necessary */
+		if (m->state != MBR_PUBLISHED)
+			return;
+
+		/* Member can be taken into service */
+		m->state = MBR_JOINED;
+		tipc_group_open(m, usr_wakeup);
+		tipc_group_update_member(m, 0);
+		tipc_group_proto_xmit(grp, m, GRP_ADV_MSG, xmitq);
+		tipc_group_create_event(grp, m, TIPC_PUBLISHED,
+					m->bc_syncpt, inputq);
+		return;
+	case GRP_LEAVE_MSG:
+		if (!m)
+			return;
+		m->bc_syncpt = msg_grp_bc_syncpt(hdr);
+		list_del_init(&m->list);
+		tipc_group_open(m, usr_wakeup);
+		tipc_group_decr_active(grp, m);
+		m->state = MBR_LEAVING;
+		tipc_group_create_event(grp, m, TIPC_WITHDRAWN,
+					m->bc_syncpt, inputq);
+		return;
+	case GRP_ADV_MSG:
+		if (!m)
+			return;
+		m->window += msg_adv_win(hdr);
+		tipc_group_open(m, usr_wakeup);
+		return;
+	case GRP_ACK_MSG:
+		if (!m)
+			return;
+		m->bc_acked = msg_grp_bc_acked(hdr);
+		if (--grp->bc_ackers)
+			return;
+		list_del_init(&m->small_win);
+		*m->group->open = true;
+		*usr_wakeup = true;
+		tipc_group_update_member(m, 0);
+		return;
+	case GRP_RECLAIM_MSG:
+		if (!m)
+			return;
+		tipc_group_proto_xmit(grp, m, GRP_REMIT_MSG, xmitq);
+		m->window = ADV_IDLE;
+		tipc_group_open(m, usr_wakeup);
+		return;
+	case GRP_REMIT_MSG:
+		if (!m || m->state != MBR_RECLAIMING)
+			return;
+
+		remitted = msg_grp_remitted(hdr);
+
+		/* Messages preceding the REMIT still in receive queue */
+		if (m->advertised > remitted) {
+			m->state = MBR_REMITTED;
+			in_flight = m->advertised - remitted;
+			m->advertised = ADV_IDLE + in_flight;
+			return;
+		}
+		/* This should never happen */
+		if (m->advertised < remitted)
+			pr_warn_ratelimited("Unexpected REMIT msg\n");
+
+		/* All messages preceding the REMIT have been read */
+		m->state = MBR_JOINED;
+		grp->active_cnt--;
+		m->advertised = ADV_IDLE;
+
+		/* Set oldest pending member to active and advertise */
+		if (list_empty(&grp->pending))
+			return;
+		pm = list_first_entry(&grp->pending, struct tipc_member, list);
+		pm->state = MBR_ACTIVE;
+		list_move_tail(&pm->list, &grp->active);
+		grp->active_cnt++;
+		if (pm->advertised <= (ADV_ACTIVE * 3 / 4))
+			tipc_group_proto_xmit(grp, pm, GRP_ADV_MSG, xmitq);
+		return;
+	default:
+		pr_warn("Received unknown GROUP_PROTO message\n");
+	}
+}
+
+/* tipc_group_member_evt() - receive and handle a member up/down event
+ */
+void tipc_group_member_evt(struct tipc_group *grp,
+			   bool *usr_wakeup,
+			   int *sk_rcvbuf,
+			   struct tipc_msg *hdr,
+			   struct sk_buff_head *inputq,
+			   struct sk_buff_head *xmitq)
+{
+	struct tipc_event *evt = (void *)msg_data(hdr);
+	u32 instance = evt->found_lower;
+	u32 node = evt->port.node;
+	u32 port = evt->port.ref;
+	int event = evt->event;
+	struct tipc_member *m;
+	struct net *net;
+	u32 self;
+
+	if (!grp)
+		return;
+
+	net = grp->net;
+	self = tipc_own_addr(net);
+	if (!grp->loopback && node == self && port == grp->portid)
+		return;
+
+	m = tipc_group_find_member(grp, node, port);
+
+	switch (event) {
+	case TIPC_PUBLISHED:
+		/* Send and wait for arrival of JOIN message if necessary */
+		if (!m) {
+			m = tipc_group_create_member(grp, node, port, instance,
+						     MBR_PUBLISHED);
+			if (!m)
+				break;
+			tipc_group_update_member(m, 0);
+			tipc_group_proto_xmit(grp, m, GRP_JOIN_MSG, xmitq);
+			break;
+		}
+
+		if (m->state != MBR_JOINING)
+			break;
+
+		/* Member can be taken into service */
+		m->instance = instance;
+		m->state = MBR_JOINED;
+		tipc_group_open(m, usr_wakeup);
+		tipc_group_update_member(m, 0);
+		tipc_group_proto_xmit(grp, m, GRP_JOIN_MSG, xmitq);
+		tipc_group_create_event(grp, m, TIPC_PUBLISHED,
+					m->bc_syncpt, inputq);
+		break;
+	case TIPC_WITHDRAWN:
+		if (!m)
+			break;
+
+		tipc_group_decr_active(grp, m);
+		m->state = MBR_LEAVING;
+		list_del_init(&m->list);
+		tipc_group_open(m, usr_wakeup);
+
+		/* Only send event if no LEAVE message can be expected */
+		if (!tipc_node_is_up(net, node))
+			tipc_group_create_event(grp, m, TIPC_WITHDRAWN,
+						m->bc_rcv_nxt, inputq);
+		break;
+	default:
+		break;
+	}
+	*sk_rcvbuf = tipc_group_rcvbuf_limit(grp);
+}
+
+int tipc_group_fill_sock_diag(struct tipc_group *grp, struct sk_buff *skb)
+{
+	struct nlattr *group = nla_nest_start(skb, TIPC_NLA_SOCK_GROUP);
+
+	if (nla_put_u32(skb, TIPC_NLA_SOCK_GROUP_ID,
+			grp->type) ||
+	    nla_put_u32(skb, TIPC_NLA_SOCK_GROUP_INSTANCE,
+			grp->instance) ||
+	    nla_put_u32(skb, TIPC_NLA_SOCK_GROUP_BC_SEND_NEXT,
+			grp->bc_snd_nxt))
+		goto group_msg_cancel;
+
+	if (grp->scope == TIPC_NODE_SCOPE)
+		if (nla_put_flag(skb, TIPC_NLA_SOCK_GROUP_NODE_SCOPE))
+			goto group_msg_cancel;
+
+	if (grp->scope == TIPC_CLUSTER_SCOPE)
+		if (nla_put_flag(skb, TIPC_NLA_SOCK_GROUP_CLUSTER_SCOPE))
+			goto group_msg_cancel;
+
+	if (*grp->open)
+		if (nla_put_flag(skb, TIPC_NLA_SOCK_GROUP_OPEN))
+			goto group_msg_cancel;
+
+	nla_nest_end(skb, group);
+	return 0;
+
+group_msg_cancel:
+	nla_nest_cancel(skb, group);
+	return -1;
+}