path: root/net/tipc/group.c

/*
 * net/tipc/group.c: TIPC group messaging code
 *
 * Copyright (c) 2017, Ericsson AB
 * Copyright (c) 2020, Red Hat Inc
 * 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 *