linux/net/tipc/bcast.c
Jon Maloy e654f9f53b tipc: clean up skb list lock handling on send path
The policy for handling the skb list locks on the send and receive paths
is simple.

- On the send path we never need to grab the lock on the 'xmitq' list
  when the destination is an exernal node.

- On the receive path we always need to grab the lock on the 'inputq'
  list, irrespective of source node.

However, when transmitting node local messages those will eventually
end up on the receive path of a local socket, meaning that the argument
'xmitq' in tipc_node_xmit() will become the 'ínputq' argument in  the
function tipc_sk_rcv(). This has been handled by always initializing
the spinlock of the 'xmitq' list at message creation, just in case it
may end up on the receive path later, and despite knowing that the lock
in most cases never will be used.

This approach is inaccurate and confusing, and has also concealed the
fact that the stated 'no lock grabbing' policy for the send path is
violated in some cases.

We now clean up this by never initializing the lock at message creation,
instead doing this at the moment we find that the message actually will
enter the receive path. At the same time we fix the four locations
where we incorrectly access the spinlock on the send/error path.

This patch also reverts commit d12cffe932 ("tipc: ensure head->lock
is initialised") which has now become redundant.

CC: Eric Dumazet <edumazet@google.com>
Reported-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-18 14:01:07 -07:00

846 lines
22 KiB
C

/*
* net/tipc/bcast.c: TIPC broadcast code
*
* Copyright (c) 2004-2006, 2014-2017, Ericsson AB
* Copyright (c) 2004, Intel Corporation.
* Copyright (c) 2005, 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 <linux/tipc_config.h>
#include "socket.h"
#include "msg.h"
#include "bcast.h"
#include "link.h"
#include "name_table.h"
#define BCLINK_WIN_DEFAULT 50 /* bcast link window size (default) */
#define BCLINK_WIN_MIN 32 /* bcast minimum link window size */
const char tipc_bclink_name[] = "broadcast-link";
/**
* struct tipc_bc_base - base structure for keeping broadcast send state
* @link: broadcast send link structure
* @inputq: data input queue; will only carry SOCK_WAKEUP messages
* @dests: array keeping number of reachable destinations per bearer
* @primary_bearer: a bearer having links to all broadcast destinations, if any
* @bcast_support: indicates if primary bearer, if any, supports broadcast
* @force_bcast: forces broadcast for multicast traffic
* @rcast_support: indicates if all peer nodes support replicast
* @force_rcast: forces replicast for multicast traffic
* @rc_ratio: dest count as percentage of cluster size where send method changes
* @bc_threshold: calculated from rc_ratio; if dests > threshold use broadcast
*/
struct tipc_bc_base {
struct tipc_link *link;
struct sk_buff_head inputq;
int dests[MAX_BEARERS];
int primary_bearer;
bool bcast_support;
bool force_bcast;
bool rcast_support;
bool force_rcast;
int rc_ratio;
int bc_threshold;
};
static struct tipc_bc_base *tipc_bc_base(struct net *net)
{
return tipc_net(net)->bcbase;
}
/* tipc_bcast_get_mtu(): -get the MTU currently used by broadcast link
* Note: the MTU is decremented to give room for a tunnel header, in
* case the message needs to be sent as replicast
*/
int tipc_bcast_get_mtu(struct net *net)
{
return tipc_link_mtu(tipc_bc_sndlink(net)) - INT_H_SIZE;
}
void tipc_bcast_disable_rcast(struct net *net)
{
tipc_bc_base(net)->rcast_support = false;
}
static void tipc_bcbase_calc_bc_threshold(struct net *net)
{
struct tipc_bc_base *bb = tipc_bc_base(net);
int cluster_size = tipc_link_bc_peers(tipc_bc_sndlink(net));
bb->bc_threshold = 1 + (cluster_size * bb->rc_ratio / 100);
}
/* tipc_bcbase_select_primary(): find a bearer with links to all destinations,
* if any, and make it primary bearer
*/
static void tipc_bcbase_select_primary(struct net *net)
{
struct tipc_bc_base *bb = tipc_bc_base(net);
int all_dests = tipc_link_bc_peers(bb->link);
int i, mtu, prim;
bb->primary_bearer = INVALID_BEARER_ID;
bb->bcast_support = true;
if (!all_dests)
return;
for (i = 0; i < MAX_BEARERS; i++) {
if (!bb->dests[i])
continue;
mtu = tipc_bearer_mtu(net, i);
if (mtu < tipc_link_mtu(bb->link))
tipc_link_set_mtu(bb->link, mtu);
bb->bcast_support &= tipc_bearer_bcast_support(net, i);
if (bb->dests[i] < all_dests)
continue;
bb->primary_bearer = i;
/* Reduce risk that all nodes select same primary */
if ((i ^ tipc_own_addr(net)) & 1)
break;
}
prim = bb->primary_bearer;
if (prim != INVALID_BEARER_ID)
bb->bcast_support = tipc_bearer_bcast_support(net, prim);
}
void tipc_bcast_inc_bearer_dst_cnt(struct net *net, int bearer_id)
{
struct tipc_bc_base *bb = tipc_bc_base(net);
tipc_bcast_lock(net);
bb->dests[bearer_id]++;
tipc_bcbase_select_primary(net);
tipc_bcast_unlock(net);
}
void tipc_bcast_dec_bearer_dst_cnt(struct net *net, int bearer_id)
{
struct tipc_bc_base *bb = tipc_bc_base(net);
tipc_bcast_lock(net);
bb->dests[bearer_id]--;
tipc_bcbase_select_primary(net);
tipc_bcast_unlock(net);
}
/* tipc_bcbase_xmit - broadcast a packet queue across one or more bearers
*
* Note that number of reachable destinations, as indicated in the dests[]
* array, may transitionally differ from the number of destinations indicated
* in each sent buffer. We can sustain this. Excess destination nodes will
* drop and never acknowledge the unexpected packets, and missing destinations
* will either require retransmission (if they are just about to be added to
* the bearer), or be removed from the buffer's 'ackers' counter (if they
* just went down)
*/
static void tipc_bcbase_xmit(struct net *net, struct sk_buff_head *xmitq)
{
int bearer_id;
struct tipc_bc_base *bb = tipc_bc_base(net);
struct sk_buff *skb, *_skb;
struct sk_buff_head _xmitq;
if (skb_queue_empty(xmitq))
return;
/* The typical case: at least one bearer has links to all nodes */
bearer_id = bb->primary_bearer;
if (bearer_id >= 0) {
tipc_bearer_bc_xmit(net, bearer_id, xmitq);
return;
}
/* We have to transmit across all bearers */
__skb_queue_head_init(&_xmitq);
for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) {
if (!bb->dests[bearer_id])
continue;
skb_queue_walk(xmitq, skb) {
_skb = pskb_copy_for_clone(skb, GFP_ATOMIC);
if (!_skb)
break;
__skb_queue_tail(&_xmitq, _skb);
}
tipc_bearer_bc_xmit(net, bearer_id, &_xmitq);
}
__skb_queue_purge(xmitq);
__skb_queue_purge(&_xmitq);
}
static void tipc_bcast_select_xmit_method(struct net *net, int dests,
struct tipc_mc_method *method)
{
struct tipc_bc_base *bb = tipc_bc_base(net);
unsigned long exp = method->expires;
/* Broadcast supported by used bearer/bearers? */
if (!bb->bcast_support) {
method->rcast = true;
return;
}
/* Any destinations which don't support replicast ? */
if (!bb->rcast_support) {
method->rcast = false;
return;
}
/* Can current method be changed ? */
method->expires = jiffies + TIPC_METHOD_EXPIRE;
if (method->mandatory)
return;
if (!(tipc_net(net)->capabilities & TIPC_MCAST_RBCTL) &&
time_before(jiffies, exp))
return;
/* Configuration as force 'broadcast' method */
if (bb->force_bcast) {
method->rcast = false;
return;
}
/* Configuration as force 'replicast' method */
if (bb->force_rcast) {
method->rcast = true;
return;
}
/* Configuration as 'autoselect' or default method */
/* Determine method to use now */
method->rcast = dests <= bb->bc_threshold;
}
/* tipc_bcast_xmit - broadcast the buffer chain to all external nodes
* @net: the applicable net namespace
* @pkts: chain of buffers containing message
* @cong_link_cnt: set to 1 if broadcast link is congested, otherwise 0
* Consumes the buffer chain.
* Returns 0 if success, otherwise errno: -EHOSTUNREACH,-EMSGSIZE
*/
static int tipc_bcast_xmit(struct net *net, struct sk_buff_head *pkts,
u16 *cong_link_cnt)
{
struct tipc_link *l = tipc_bc_sndlink(net);
struct sk_buff_head xmitq;
int rc = 0;
__skb_queue_head_init(&xmitq);
tipc_bcast_lock(net);
if (tipc_link_bc_peers(l))
rc = tipc_link_xmit(l, pkts, &xmitq);
tipc_bcast_unlock(net);
tipc_bcbase_xmit(net, &xmitq);
__skb_queue_purge(pkts);
if (rc == -ELINKCONG) {
*cong_link_cnt = 1;
rc = 0;
}
return rc;
}
/* tipc_rcast_xmit - replicate and send a message to given destination nodes
* @net: the applicable net namespace
* @pkts: chain of buffers containing message
* @dests: list of destination nodes
* @cong_link_cnt: returns number of congested links
* @cong_links: returns identities of congested links
* Returns 0 if success, otherwise errno
*/
static int tipc_rcast_xmit(struct net *net, struct sk_buff_head *pkts,
struct tipc_nlist *dests, u16 *cong_link_cnt)
{
struct tipc_dest *dst, *tmp;
struct sk_buff_head _pkts;
u32 dnode, selector;
selector = msg_link_selector(buf_msg(skb_peek(pkts)));
__skb_queue_head_init(&_pkts);
list_for_each_entry_safe(dst, tmp, &dests->list, list) {
dnode = dst->node;
if (!tipc_msg_pskb_copy(dnode, pkts, &_pkts))
return -ENOMEM;
/* Any other return value than -ELINKCONG is ignored */
if (tipc_node_xmit(net, &_pkts, dnode, selector) == -ELINKCONG)
(*cong_link_cnt)++;
}
return 0;
}
/* tipc_mcast_send_sync - deliver a dummy message with SYN bit
* @net: the applicable net namespace
* @skb: socket buffer to copy
* @method: send method to be used
* @dests: destination nodes for message.
* @cong_link_cnt: returns number of encountered congested destination links
* Returns 0 if success, otherwise errno
*/
static int tipc_mcast_send_sync(struct net *net, struct sk_buff *skb,
struct tipc_mc_method *method,
struct tipc_nlist *dests,
u16 *cong_link_cnt)
{
struct tipc_msg *hdr, *_hdr;
struct sk_buff_head tmpq;
struct sk_buff *_skb;
/* Is a cluster supporting with new capabilities ? */
if (!(tipc_net(net)->capabilities & TIPC_MCAST_RBCTL))
return 0;
hdr = buf_msg(skb);
if (msg_user(hdr) == MSG_FRAGMENTER)
hdr = msg_inner_hdr(hdr);
if (msg_type(hdr) != TIPC_MCAST_MSG)
return 0;
/* Allocate dummy message */
_skb = tipc_buf_acquire(MCAST_H_SIZE, GFP_KERNEL);
if (!_skb)
return -ENOMEM;
/* Preparing for 'synching' header */
msg_set_syn(hdr, 1);
/* Copy skb's header into a dummy header */
skb_copy_to_linear_data(_skb, hdr, MCAST_H_SIZE);
skb_orphan(_skb);
/* Reverse method for dummy message */
_hdr = buf_msg(_skb);
msg_set_size(_hdr, MCAST_H_SIZE);
msg_set_is_rcast(_hdr, !msg_is_rcast(hdr));
__skb_queue_head_init(&tmpq);
__skb_queue_tail(&tmpq, _skb);
if (method->rcast)
tipc_bcast_xmit(net, &tmpq, cong_link_cnt);
else
tipc_rcast_xmit(net, &tmpq, dests, cong_link_cnt);
/* This queue should normally be empty by now */
__skb_queue_purge(&tmpq);
return 0;
}
/* tipc_mcast_xmit - deliver message to indicated destination nodes
* and to identified node local sockets
* @net: the applicable net namespace
* @pkts: chain of buffers containing message
* @method: send method to be used
* @dests: destination nodes for message.
* @cong_link_cnt: returns number of encountered congested destination links
* Consumes buffer chain.
* Returns 0 if success, otherwise errno
*/
int tipc_mcast_xmit(struct net *net, struct sk_buff_head *pkts,
struct tipc_mc_method *method, struct tipc_nlist *dests,
u16 *cong_link_cnt)
{
struct sk_buff_head inputq, localq;
bool rcast = method->rcast;
struct tipc_msg *hdr;
struct sk_buff *skb;
int rc = 0;
skb_queue_head_init(&inputq);
__skb_queue_head_init(&localq);
/* Clone packets before they are consumed by next call */
if (dests->local && !tipc_msg_reassemble(pkts, &localq)) {
rc = -ENOMEM;
goto exit;
}
/* Send according to determined transmit method */
if (dests->remote) {
tipc_bcast_select_xmit_method(net, dests->remote, method);
skb = skb_peek(pkts);
hdr = buf_msg(skb);
if (msg_user(hdr) == MSG_FRAGMENTER)
hdr = msg_inner_hdr(hdr);
msg_set_is_rcast(hdr, method->rcast);
/* Switch method ? */
if (rcast != method->rcast)
tipc_mcast_send_sync(net, skb, method,
dests, cong_link_cnt);
if (method->rcast)
rc = tipc_rcast_xmit(net, pkts, dests, cong_link_cnt);
else
rc = tipc_bcast_xmit(net, pkts, cong_link_cnt);
}
if (dests->local) {
tipc_loopback_trace(net, &localq);
tipc_sk_mcast_rcv(net, &localq, &inputq);
}
exit:
/* This queue should normally be empty by now */
__skb_queue_purge(pkts);
return rc;
}
/* tipc_bcast_rcv - receive a broadcast packet, and deliver to rcv link
*
* RCU is locked, no other locks set
*/
int tipc_bcast_rcv(struct net *net, struct tipc_link *l, struct sk_buff *skb)
{
struct tipc_msg *hdr = buf_msg(skb);
struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq;
struct sk_buff_head xmitq;
int rc;
__skb_queue_head_init(&xmitq);
if (msg_mc_netid(hdr) != tipc_netid(net) || !tipc_link_is_up(l)) {
kfree_skb(skb);
return 0;
}
tipc_bcast_lock(net);
if (msg_user(hdr) == BCAST_PROTOCOL)
rc = tipc_link_bc_nack_rcv(l, skb, &xmitq);
else
rc = tipc_link_rcv(l, skb, NULL);
tipc_bcast_unlock(net);
tipc_bcbase_xmit(net, &xmitq);
/* Any socket wakeup messages ? */
if (!skb_queue_empty(inputq))
tipc_sk_rcv(net, inputq);
return rc;
}
/* tipc_bcast_ack_rcv - receive and handle a broadcast acknowledge
*
* RCU is locked, no other locks set
*/
void tipc_bcast_ack_rcv(struct net *net, struct tipc_link *l,
struct tipc_msg *hdr)
{
struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq;
u16 acked = msg_bcast_ack(hdr);
struct sk_buff_head xmitq;
/* Ignore bc acks sent by peer before bcast synch point was received */
if (msg_bc_ack_invalid(hdr))
return;
__skb_queue_head_init(&xmitq);
tipc_bcast_lock(net);
tipc_link_bc_ack_rcv(l, acked, &xmitq);
tipc_bcast_unlock(net);
tipc_bcbase_xmit(net, &xmitq);
/* Any socket wakeup messages ? */
if (!skb_queue_empty(inputq))
tipc_sk_rcv(net, inputq);
}
/* tipc_bcast_synch_rcv - check and update rcv link with peer's send state
*
* RCU is locked, no other locks set
*/
int tipc_bcast_sync_rcv(struct net *net, struct tipc_link *l,
struct tipc_msg *hdr)
{
struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq;
struct sk_buff_head xmitq;
int rc = 0;
__skb_queue_head_init(&xmitq);
tipc_bcast_lock(net);
if (msg_type(hdr) != STATE_MSG) {
tipc_link_bc_init_rcv(l, hdr);
} else if (!msg_bc_ack_invalid(hdr)) {
tipc_link_bc_ack_rcv(l, msg_bcast_ack(hdr), &xmitq);
rc = tipc_link_bc_sync_rcv(l, hdr, &xmitq);
}
tipc_bcast_unlock(net);
tipc_bcbase_xmit(net, &xmitq);
/* Any socket wakeup messages ? */
if (!skb_queue_empty(inputq))
tipc_sk_rcv(net, inputq);
return rc;
}
/* tipc_bcast_add_peer - add a peer node to broadcast link and bearer
*
* RCU is locked, node lock is set
*/
void tipc_bcast_add_peer(struct net *net, struct tipc_link *uc_l,
struct sk_buff_head *xmitq)
{
struct tipc_link *snd_l = tipc_bc_sndlink(net);
tipc_bcast_lock(net);
tipc_link_add_bc_peer(snd_l, uc_l, xmitq);
tipc_bcbase_select_primary(net);
tipc_bcbase_calc_bc_threshold(net);
tipc_bcast_unlock(net);
}
/* tipc_bcast_remove_peer - remove a peer node from broadcast link and bearer
*
* RCU is locked, node lock is set
*/
void tipc_bcast_remove_peer(struct net *net, struct tipc_link *rcv_l)
{
struct tipc_link *snd_l = tipc_bc_sndlink(net);
struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq;
struct sk_buff_head xmitq;
__skb_queue_head_init(&xmitq);
tipc_bcast_lock(net);
tipc_link_remove_bc_peer(snd_l, rcv_l, &xmitq);
tipc_bcbase_select_primary(net);
tipc_bcbase_calc_bc_threshold(net);
tipc_bcast_unlock(net);
tipc_bcbase_xmit(net, &xmitq);
/* Any socket wakeup messages ? */
if (!skb_queue_empty(inputq))
tipc_sk_rcv(net, inputq);
}
int tipc_bclink_reset_stats(struct net *net)
{
struct tipc_link *l = tipc_bc_sndlink(net);
if (!l)
return -ENOPROTOOPT;
tipc_bcast_lock(net);
tipc_link_reset_stats(l);
tipc_bcast_unlock(net);
return 0;
}
static int tipc_bc_link_set_queue_limits(struct net *net, u32 limit)
{
struct tipc_link *l = tipc_bc_sndlink(net);
if (!l)
return -ENOPROTOOPT;
if (limit < BCLINK_WIN_MIN)
limit = BCLINK_WIN_MIN;
if (limit > TIPC_MAX_LINK_WIN)
return -EINVAL;
tipc_bcast_lock(net);
tipc_link_set_queue_limits(l, limit);
tipc_bcast_unlock(net);
return 0;
}
static int tipc_bc_link_set_broadcast_mode(struct net *net, u32 bc_mode)
{
struct tipc_bc_base *bb = tipc_bc_base(net);
switch (bc_mode) {
case BCLINK_MODE_BCAST:
if (!bb->bcast_support)
return -ENOPROTOOPT;
bb->force_bcast = true;
bb->force_rcast = false;
break;
case BCLINK_MODE_RCAST:
if (!bb->rcast_support)
return -ENOPROTOOPT;
bb->force_bcast = false;
bb->force_rcast = true;
break;
case BCLINK_MODE_SEL:
if (!bb->bcast_support || !bb->rcast_support)
return -ENOPROTOOPT;
bb->force_bcast = false;
bb->force_rcast = false;
break;
default:
return -EINVAL;
}
return 0;
}
static int tipc_bc_link_set_broadcast_ratio(struct net *net, u32 bc_ratio)
{
struct tipc_bc_base *bb = tipc_bc_base(net);
if (!bb->bcast_support || !bb->rcast_support)
return -ENOPROTOOPT;
if (bc_ratio > 100 || bc_ratio <= 0)
return -EINVAL;
bb->rc_ratio = bc_ratio;
tipc_bcast_lock(net);
tipc_bcbase_calc_bc_threshold(net);
tipc_bcast_unlock(net);
return 0;
}
int tipc_nl_bc_link_set(struct net *net, struct nlattr *attrs[])
{
int err;
u32 win;
u32 bc_mode;
u32 bc_ratio;
struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
if (!attrs[TIPC_NLA_LINK_PROP])
return -EINVAL;
err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP], props);
if (err)
return err;
if (!props[TIPC_NLA_PROP_WIN] &&
!props[TIPC_NLA_PROP_BROADCAST] &&
!props[TIPC_NLA_PROP_BROADCAST_RATIO]) {
return -EOPNOTSUPP;
}
if (props[TIPC_NLA_PROP_BROADCAST]) {
bc_mode = nla_get_u32(props[TIPC_NLA_PROP_BROADCAST]);
err = tipc_bc_link_set_broadcast_mode(net, bc_mode);
}
if (!err && props[TIPC_NLA_PROP_BROADCAST_RATIO]) {
bc_ratio = nla_get_u32(props[TIPC_NLA_PROP_BROADCAST_RATIO]);
err = tipc_bc_link_set_broadcast_ratio(net, bc_ratio);
}
if (!err && props[TIPC_NLA_PROP_WIN]) {
win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
err = tipc_bc_link_set_queue_limits(net, win);
}
return err;
}
int tipc_bcast_init(struct net *net)
{
struct tipc_net *tn = tipc_net(net);
struct tipc_bc_base *bb = NULL;
struct tipc_link *l = NULL;
bb = kzalloc(sizeof(*bb), GFP_KERNEL);
if (!bb)
goto enomem;
tn->bcbase = bb;
spin_lock_init(&tipc_net(net)->bclock);
if (!tipc_link_bc_create(net, 0, 0,
FB_MTU,
BCLINK_WIN_DEFAULT,
0,
&bb->inputq,
NULL,
NULL,
&l))
goto enomem;
bb->link = l;
tn->bcl = l;
bb->rc_ratio = 10;
bb->rcast_support = true;
return 0;
enomem:
kfree(bb);
kfree(l);
return -ENOMEM;
}
void tipc_bcast_stop(struct net *net)
{
struct tipc_net *tn = net_generic(net, tipc_net_id);
synchronize_net();
kfree(tn->bcbase);
kfree(tn->bcl);
}
void tipc_nlist_init(struct tipc_nlist *nl, u32 self)
{
memset(nl, 0, sizeof(*nl));
INIT_LIST_HEAD(&nl->list);
nl->self = self;
}
void tipc_nlist_add(struct tipc_nlist *nl, u32 node)
{
if (node == nl->self)
nl->local = true;
else if (tipc_dest_push(&nl->list, node, 0))
nl->remote++;
}
void tipc_nlist_del(struct tipc_nlist *nl, u32 node)
{
if (node == nl->self)
nl->local = false;
else if (tipc_dest_del(&nl->list, node, 0))
nl->remote--;
}
void tipc_nlist_purge(struct tipc_nlist *nl)
{
tipc_dest_list_purge(&nl->list);
nl->remote = 0;
nl->local = false;
}
u32 tipc_bcast_get_broadcast_mode(struct net *net)
{
struct tipc_bc_base *bb = tipc_bc_base(net);
if (bb->force_bcast)
return BCLINK_MODE_BCAST;
if (bb->force_rcast)
return BCLINK_MODE_RCAST;
if (bb->bcast_support && bb->rcast_support)
return BCLINK_MODE_SEL;
return 0;
}
u32 tipc_bcast_get_broadcast_ratio(struct net *net)
{
struct tipc_bc_base *bb = tipc_bc_base(net);
return bb->rc_ratio;
}
void tipc_mcast_filter_msg(struct net *net, struct sk_buff_head *defq,
struct sk_buff_head *inputq)
{
struct sk_buff *skb, *_skb, *tmp;
struct tipc_msg *hdr, *_hdr;
bool match = false;
u32 node, port;
skb = skb_peek(inputq);
if (!skb)
return;
hdr = buf_msg(skb);
if (likely(!msg_is_syn(hdr) && skb_queue_empty(defq)))
return;
node = msg_orignode(hdr);
if (node == tipc_own_addr(net))
return;
port = msg_origport(hdr);
/* Has the twin SYN message already arrived ? */
skb_queue_walk(defq, _skb) {
_hdr = buf_msg(_skb);
if (msg_orignode(_hdr) != node)
continue;
if (msg_origport(_hdr) != port)
continue;
match = true;
break;
}
if (!match) {
if (!msg_is_syn(hdr))
return;
__skb_dequeue(inputq);
__skb_queue_tail(defq, skb);
return;
}
/* Deliver non-SYN message from other link, otherwise queue it */
if (!msg_is_syn(hdr)) {
if (msg_is_rcast(hdr) != msg_is_rcast(_hdr))
return;
__skb_dequeue(inputq);
__skb_queue_tail(defq, skb);
return;
}
/* Queue non-SYN/SYN message from same link */
if (msg_is_rcast(hdr) == msg_is_rcast(_hdr)) {
__skb_dequeue(inputq);
__skb_queue_tail(defq, skb);
return;
}
/* Matching SYN messages => return the one with data, if any */
__skb_unlink(_skb, defq);
if (msg_data_sz(hdr)) {
kfree_skb(_skb);
} else {
__skb_dequeue(inputq);
kfree_skb(skb);
__skb_queue_tail(inputq, _skb);
}
/* Deliver subsequent non-SYN messages from same peer */
skb_queue_walk_safe(defq, _skb, tmp) {
_hdr = buf_msg(_skb);
if (msg_orignode(_hdr) != node)
continue;
if (msg_origport(_hdr) != port)
continue;
if (msg_is_syn(_hdr))
break;
__skb_unlink(_skb, defq);
__skb_queue_tail(inputq, _skb);
}
}