WSL2-Linux-Kernel/net/tipc/subscr.c

175 строки
5.4 KiB
C

/*
* net/tipc/subscr.c: TIPC network topology service
*
* Copyright (c) 2000-2017, Ericsson AB
* Copyright (c) 2005-2007, 2010-2013, 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 "name_table.h"
#include "subscr.h"
static void tipc_sub_send_event(struct tipc_subscription *sub,
u32 found_lower, u32 found_upper,
u32 event, u32 port, u32 node)
{
struct tipc_event *evt = &sub->evt;
if (sub->inactive)
return;
tipc_evt_write(evt, event, event);
tipc_evt_write(evt, found_lower, found_lower);
tipc_evt_write(evt, found_upper, found_upper);
tipc_evt_write(evt, port.ref, port);
tipc_evt_write(evt, port.node, node);
tipc_topsrv_queue_evt(sub->net, sub->conid, event, evt);
}
/**
* tipc_sub_check_overlap - test for subscription overlap with the
* given values
*
* Returns 1 if there is overlap, otherwise 0.
*/
int tipc_sub_check_overlap(struct tipc_name_seq *seq, u32 found_lower,
u32 found_upper)
{
if (found_lower < seq->lower)
found_lower = seq->lower;
if (found_upper > seq->upper)
found_upper = seq->upper;
if (found_lower > found_upper)
return 0;
return 1;
}
void tipc_sub_report_overlap(struct tipc_subscription *sub,
u32 found_lower, u32 found_upper,
u32 event, u32 port, u32 node,
u32 scope, int must)
{
struct tipc_subscr *s = &sub->evt.s;
u32 filter = tipc_sub_read(s, filter);
struct tipc_name_seq seq;
seq.type = tipc_sub_read(s, seq.type);
seq.lower = tipc_sub_read(s, seq.lower);
seq.upper = tipc_sub_read(s, seq.upper);
if (!tipc_sub_check_overlap(&seq, found_lower, found_upper))
return;
if (!must && !(filter & TIPC_SUB_PORTS))
return;
if (filter & TIPC_SUB_CLUSTER_SCOPE && scope == TIPC_NODE_SCOPE)
return;
if (filter & TIPC_SUB_NODE_SCOPE && scope != TIPC_NODE_SCOPE)
return;
spin_lock(&sub->lock);
tipc_sub_send_event(sub, found_lower, found_upper,
event, port, node);
spin_unlock(&sub->lock);
}
static void tipc_sub_timeout(struct timer_list *t)
{
struct tipc_subscription *sub = from_timer(sub, t, timer);
struct tipc_subscr *s = &sub->evt.s;
spin_lock(&sub->lock);
tipc_sub_send_event(sub, s->seq.lower, s->seq.upper,
TIPC_SUBSCR_TIMEOUT, 0, 0);
sub->inactive = true;
spin_unlock(&sub->lock);
}
static void tipc_sub_kref_release(struct kref *kref)
{
kfree(container_of(kref, struct tipc_subscription, kref));
}
void tipc_sub_put(struct tipc_subscription *subscription)
{
kref_put(&subscription->kref, tipc_sub_kref_release);
}
void tipc_sub_get(struct tipc_subscription *subscription)
{
kref_get(&subscription->kref);
}
struct tipc_subscription *tipc_sub_subscribe(struct net *net,
struct tipc_subscr *s,
int conid)
{
u32 filter = tipc_sub_read(s, filter);
struct tipc_subscription *sub;
u32 timeout;
if ((filter & TIPC_SUB_PORTS && filter & TIPC_SUB_SERVICE) ||
(tipc_sub_read(s, seq.lower) > tipc_sub_read(s, seq.upper))) {
pr_warn("Subscription rejected, illegal request\n");
return NULL;
}
sub = kmalloc(sizeof(*sub), GFP_ATOMIC);
if (!sub) {
pr_warn("Subscription rejected, no memory\n");
return NULL;
}
INIT_LIST_HEAD(&sub->service_list);
INIT_LIST_HEAD(&sub->sub_list);
sub->net = net;
sub->conid = conid;
sub->inactive = false;
memcpy(&sub->evt.s, s, sizeof(*s));
spin_lock_init(&sub->lock);
kref_init(&sub->kref);
if (!tipc_nametbl_subscribe(sub)) {
kfree(sub);
return NULL;
}
timer_setup(&sub->timer, tipc_sub_timeout, 0);
timeout = tipc_sub_read(&sub->evt.s, timeout);
if (timeout != TIPC_WAIT_FOREVER)
mod_timer(&sub->timer, jiffies + msecs_to_jiffies(timeout));
return sub;
}
void tipc_sub_unsubscribe(struct tipc_subscription *sub)
{
tipc_nametbl_unsubscribe(sub);
if (sub->evt.s.timeout != TIPC_WAIT_FOREVER)
del_timer_sync(&sub->timer);
list_del(&sub->sub_list);
tipc_sub_put(sub);
}