Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

Pull networking updates from David Miller:
 "Highlights:

   1) Maintain the TCP retransmit queue using an rbtree, with 1GB
      windows at 100Gb this really has become necessary. From Eric
      Dumazet.

   2) Multi-program support for cgroup+bpf, from Alexei Starovoitov.

   3) Perform broadcast flooding in hardware in mv88e6xxx, from Andrew
      Lunn.

   4) Add meter action support to openvswitch, from Andy Zhou.

   5) Add a data meta pointer for BPF accessible packets, from Daniel
      Borkmann.

   6) Namespace-ify almost all TCP sysctl knobs, from Eric Dumazet.

   7) Turn on Broadcom Tags in b53 driver, from Florian Fainelli.

   8) More work to move the RTNL mutex down, from Florian Westphal.

   9) Add 'bpftool' utility, to help with bpf program introspection.
      From Jakub Kicinski.

  10) Add new 'cpumap' type for XDP_REDIRECT action, from Jesper
      Dangaard Brouer.

  11) Support 'blocks' of transformations in the packet scheduler which
      can span multiple network devices, from Jiri Pirko.

  12) TC flower offload support in cxgb4, from Kumar Sanghvi.

  13) Priority based stream scheduler for SCTP, from Marcelo Ricardo
      Leitner.

  14) Thunderbolt networking driver, from Amir Levy and Mika Westerberg.

  15) Add RED qdisc offloadability, and use it in mlxsw driver. From
      Nogah Frankel.

  16) eBPF based device controller for cgroup v2, from Roman Gushchin.

  17) Add some fundamental tracepoints for TCP, from Song Liu.

  18) Remove garbage collection from ipv6 route layer, this is a
      significant accomplishment. From Wei Wang.

  19) Add multicast route offload support to mlxsw, from Yotam Gigi"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2177 commits)
  tcp: highest_sack fix
  geneve: fix fill_info when link down
  bpf: fix lockdep splat
  net: cdc_ncm: GetNtbFormat endian fix
  openvswitch: meter: fix NULL pointer dereference in ovs_meter_cmd_reply_start
  netem: remove unnecessary 64 bit modulus
  netem: use 64 bit divide by rate
  tcp: Namespace-ify sysctl_tcp_default_congestion_control
  net: Protect iterations over net::fib_notifier_ops in fib_seq_sum()
  ipv6: set all.accept_dad to 0 by default
  uapi: fix linux/tls.h userspace compilation error
  usbnet: ipheth: prevent TX queue timeouts when device not ready
  vhost_net: conditionally enable tx polling
  uapi: fix linux/rxrpc.h userspace compilation errors
  net: stmmac: fix LPI transitioning for dwmac4
  atm: horizon: Fix irq release error
  net-sysfs: trigger netlink notification on ifalias change via sysfs
  openvswitch: Using kfree_rcu() to simplify the code
  openvswitch: Make local function ovs_nsh_key_attr_size() static
  openvswitch: Fix return value check in ovs_meter_cmd_features()
  ...

1 files changed, 871 insertions, 0 deletions

diff --git a/net/tipc/group.c b/net/tipc/group.c
new file mode 100644
index 000000000000..7821085a7dd8
--- /dev/null
+++ b/net/tipc/group.c
@@ -0,0 +1,871 @@
+/*
+ * 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 "server.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_QUARANTINED,
+	MBR_DISCOVERED,
+	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 congested;
+	struct sk_buff *event_msg;
+	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;
+	bool usr_pending;
+};
+
+struct tipc_group {
+	struct rb_root members;
+	struct list_head congested;
+	struct list_head pending;
+	struct list_head active;
+	struct list_head reclaiming;
+	struct tipc_nlist dests;
+	struct net *net;
+	int subid;
+	u32 type;
+	u32 instance;
+	u32 domain;
+	u32 scope;
+	u32 portid;
+	u16 member_cnt;
+	u16 active_cnt;
+	u16 max_active;
+	u16 bc_snd_nxt;
+	u16 bc_ackers;
+	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_decr_active(struct tipc_group *grp,
+				   struct tipc_member *m)
+{
+	if (m->state == MBR_ACTIVE || m->state == MBR_RECLAIMING)
+		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_enabled(struct tipc_member *m)
+{
+	return m->state != MBR_QUARANTINED && m->state != MBR_LEAVING;
+}
+
+static bool tipc_group_is_receiver(struct tipc_member *m)
+{
+	return m && m->state >= MBR_JOINED;
+}
+
+u32 tipc_group_exclude(struct tipc_group *grp)
+{
+	if (!grp->loopback)
+		return grp->portid;
+	return 0;
+}
+
+int tipc_group_size(struct tipc_group *grp)
+{
+	return grp->member_cnt;
+}
+
+struct tipc_group *tipc_group_create(struct net *net, u32 portid,
+				     struct tipc_group_req *mreq)
+{
+	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->congested);
+	INIT_LIST_HEAD(&grp->active);
+	INIT_LIST_HEAD(&grp->pending);
+	INIT_LIST_HEAD(&grp->reclaiming);
+	grp->members = RB_ROOT;
+	grp->net = net;
+	grp->portid = portid;
+	grp->domain = addr_domain(net, mreq->scope);
+	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;
+	if (tipc_topsrv_kern_subscr(net, portid, type, 0, ~0, &grp->subid))
+		return grp;
+	kfree(grp);
+	return NULL;
+}
+
+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);
+		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);
+}
+
+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_enabled(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 void 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;
+	}
+	rb_link_node(&m->tree_node, parent, n);
+	rb_insert_color(&m->tree_node, &grp->members);
+}
+
+static struct tipc_member *tipc_group_create_member(struct tipc_group *grp,
+						    u32 node, u32 port,
+						    int state)
+{
+	struct tipc_member *m;
+
+	m = kzalloc(sizeof(*m), GFP_ATOMIC);
+	if (!m)
+		return NULL;
+	INIT_LIST_HEAD(&m->list);
+	INIT_LIST_HEAD(&m->congested);
+	__skb_queue_head_init(&m->deferredq);
+	m->group = grp;
+	m->node = node;
+	m->port = port;
+	m->bc_acked = grp->bc_snd_nxt - 1;
+	grp->member_cnt++;
+	tipc_group_add_to_tree(grp, m);
+	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)
+{
+	tipc_group_create_member(grp, node, port, MBR_DISCOVERED);
+}
+
+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->congested);
+	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_enabled(m))
+		return;
+
+	m->window -= len;
+
+	if (m->window >= ADV_IDLE)
+		return;
+
+	if (!list_empty(&m->congested))
+		return;
+
+	/* Sort member into congested members' list */
+	list_for_each_entry_safe(_m, tmp, &grp->congested, congested) {
+		if (m->window > _m->window)
+			continue;
+		list_add_tail(&m->congested, &_m->congested);
+		return;
+	}
+	list_add_tail(&m->congested, &grp->congested);
+}
+
+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;
+
+	for (n = rb_first(&grp->members); n; n = rb_next(n)) {
+		m = container_of(n, struct tipc_member, tree_node);
+		if (tipc_group_is_enabled(m)) {
+			tipc_group_update_member(m, len);
+			m->bc_acked = prev;
+		}
+	}
+
+	/* Mark number of acknowledges to expect, if any */
+	if (ack)
+		grp->bc_ackers = grp->member_cnt;
+	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);
+	*mbr = m;
+	if (!m)
+		return false;
+	if (m->usr_pending)
+		return true;
+	if (m->window >= len)
+		return false;
+	m->usr_pending = true;
+
+	/* If not fully advertised, do it now to prevent mutual blocking */
+	adv = m->advertised;
+	state = m->state;
+	if (state < MBR_JOINED)
+		return true;
+	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)
+		return true;
+
+	if (list_empty(&grp->congested))
+		return false;
+
+	m = list_first_entry(&grp->congested, struct tipc_member, congested);
+	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_receiver(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);
+		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) {
+			tipc_group_delete_member(grp, m);
+			__skb_queue_purge(defq);
+			break;
+		}
+		if (!update)
+			continue;
+
+		blks = msg_blocks(hdr);
+		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;
+
+	m = tipc_group_find_member(grp, node, port);
+	if (!m)
+		return;
+
+	m->advertised -= blks;
+
+	switch (m->state) {
+	case MBR_JOINED:
+		/* Reclaim advertised space from least active member */
+		if (!list_empty(active) && active_cnt >= reclaim_limit) {
+			rm = list_first_entry(active, struct tipc_member, list);
+			rm->state = MBR_RECLAIMING;
+			list_move_tail(&rm->list, &grp->reclaiming);
+			tipc_group_proto_xmit(grp, rm, GRP_RECLAIM_MSG, xmitq);
+		}
+		/* If max active, become pending and wait for reclaimed space */
+		if (active_cnt >= max_active) {
+			m->state = MBR_PENDING;
+			list_add_tail(&m->list, &grp->pending);
+			break;
+		}
+		/* Otherwise become active */
+		m->state = MBR_ACTIVE;
+		list_add_tail(&m->list, &grp->active);
+		grp->active_cnt++;
+		/* Fall through */
+	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;
+		if (m->advertised < ADV_IDLE) {
+			pr_warn_ratelimited("Rcv unexpected msg after REMIT\n");
+			tipc_group_proto_xmit(grp, m, GRP_ADV_MSG, xmitq);
+		}
+		break;
+	case MBR_RECLAIMING:
+	case MBR_DISCOVERED:
+	case MBR_JOINING:
+	case MBR_LEAVING:
+	default:
+		break;
+	}
+}
+
+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);
+	}
+	__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;
+	struct tipc_msg *ehdr;
+	u16 remitted, in_flight;
+
+	if (!grp)
+		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,
+						     MBR_QUARANTINED);
+		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 (m->state == MBR_DISCOVERED) {
+			m->state = MBR_JOINING;
+		} else if (m->state == MBR_PUBLISHED) {
+			m->state = MBR_JOINED;
+			*usr_wakeup = true;
+			m->usr_pending = false;
+			tipc_group_proto_xmit(grp, m, GRP_ADV_MSG, xmitq);
+			ehdr = buf_msg(m->event_msg);
+			msg_set_grp_bc_seqno(ehdr, m->bc_syncpt);
+			__skb_queue_tail(inputq, m->event_msg);
+		}
+		if (m->window < ADV_IDLE)
+			tipc_group_update_member(m, 0);
+		else
+			list_del_init(&m->congested);
+		return;
+	case GRP_LEAVE_MSG:
+		if (!m)
+			return;
+		m->bc_syncpt = msg_grp_bc_syncpt(hdr);
+
+		/* Wait until WITHDRAW event is received */
+		if (m->state != MBR_LEAVING) {
+			tipc_group_decr_active(grp, m);
+			m->state = MBR_LEAVING;
+			return;
+		}
+		/* Otherwise deliver already received WITHDRAW event */
+		ehdr = buf_msg(m->event_msg);
+		msg_set_grp_bc_seqno(ehdr, m->bc_syncpt);
+		__skb_queue_tail(inputq, m->event_msg);
+		*usr_wakeup = true;
+		list_del_init(&m->congested);
+		return;
+	case GRP_ADV_MSG:
+		if (!m)
+			return;
+		m->window += msg_adv_win(hdr);
+		*usr_wakeup = m->usr_pending;
+		m->usr_pending = false;
+		list_del_init(&m->congested);
+		return;
+	case GRP_ACK_MSG:
+		if (!m)
+			return;
+		m->bc_acked = msg_grp_bc_acked(hdr);
+		if (--grp->bc_ackers)
+			break;
+		*usr_wakeup = true;
+		m->usr_pending = false;
+		return;
+	case GRP_RECLAIM_MSG:
+		if (!m)
+			return;
+		*usr_wakeup = m->usr_pending;
+		m->usr_pending = false;
+		tipc_group_proto_xmit(grp, m, GRP_REMIT_MSG, xmitq);
+		m->window = ADV_IDLE;
+		return;
+	case GRP_REMIT_MSG:
+		if (!m || m->state != MBR_RECLAIMING)
+			return;
+
+		list_del_init(&m->list);
+		grp->active_cnt--;
+		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;
+		}
+		/* All messages preceding the REMIT have been read */
+		if (m->advertised <= remitted) {
+			m->state = MBR_JOINED;
+			in_flight = 0;
+		}
+		/* ..and the REMIT overtaken by more messages => re-advertise */
+		if (m->advertised < remitted)
+			tipc_group_proto_xmit(grp, m, GRP_ADV_MSG, xmitq);
+
+		m->advertised = ADV_IDLE + in_flight;
+
+		/* 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 sk_buff *skb,
+			   struct sk_buff_head *inputq,
+			   struct sk_buff_head *xmitq)
+{
+	struct tipc_msg *hdr = buf_msg(skb);
+	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;
+	bool node_up;
+	u32 self;
+
+	if (!grp)
+		goto drop;
+
+	net = grp->net;
+	self = tipc_own_addr(net);
+	if (!grp->loopback && node == self && port == grp->portid)
+		goto drop;
+
+	/* Convert message before delivery to user */
+	msg_set_hdr_sz(hdr, GROUP_H_SIZE);
+	msg_set_user(hdr, TIPC_CRITICAL_IMPORTANCE);
+	msg_set_type(hdr, TIPC_GRP_MEMBER_EVT);
+	msg_set_origport(hdr, port);
+	msg_set_orignode(hdr, node);
+	msg_set_nametype(hdr, grp->type);
+	msg_set_grp_evt(hdr, event);
+
+	m = tipc_group_find_member(grp, node, port);
+
+	if (event == TIPC_PUBLISHED) {
+		if (!m)
+			m = tipc_group_create_member(grp, node, port,
+						     MBR_DISCOVERED);
+		if (!m)
+			goto drop;
+
+		/* Hold back event if JOIN message not yet received */
+		if (m->state == MBR_DISCOVERED) {
+			m->event_msg = skb;
+			m->state = MBR_PUBLISHED;
+		} else {
+			msg_set_grp_bc_seqno(hdr, m->bc_syncpt);
+			__skb_queue_tail(inputq, skb);
+			m->state = MBR_JOINED;
+			*usr_wakeup = true;
+			m->usr_pending = false;
+		}
+		m->instance = instance;
+		TIPC_SKB_CB(skb)->orig_member = m->instance;
+		tipc_group_proto_xmit(grp, m, GRP_JOIN_MSG, xmitq);
+		if (m->window < ADV_IDLE)
+			tipc_group_update_member(m, 0);
+		else
+			list_del_init(&m->congested);
+	} else if (event == TIPC_WITHDRAWN) {
+		if (!m)
+			goto drop;
+
+		TIPC_SKB_CB(skb)->orig_member = m->instance;
+
+		*usr_wakeup = true;
+		m->usr_pending = false;
+		node_up = tipc_node_is_up(net, node);
+
+		/* Hold back event if more messages might be expected */
+		if (m->state != MBR_LEAVING && node_up) {
+			m->event_msg = skb;
+			tipc_group_decr_active(grp, m);
+			m->state = MBR_LEAVING;
+		} else {
+			if (node_up)
+				msg_set_grp_bc_seqno(hdr, m->bc_syncpt);
+			else
+				msg_set_grp_bc_seqno(hdr, m->bc_rcv_nxt);
+			__skb_queue_tail(inputq, skb);
+		}
+		list_del_init(&m->congested);
+	}
+	*sk_rcvbuf = tipc_group_rcvbuf_limit(grp);
+	return;
+drop:
+	kfree_skb(skb);
+}