| /* |
| * net/tipc/subscr.c: TIPC subscription service |
| * |
| * Copyright (c) 2003-2006, Ericsson AB |
| * Copyright (c) 2005, 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 "dbg.h" |
| #include "subscr.h" |
| #include "name_table.h" |
| #include "ref.h" |
| |
| /** |
| * struct subscriber - TIPC network topology subscriber |
| * @ref: object reference to subscriber object itself |
| * @lock: pointer to spinlock controlling access to subscriber object |
| * @subscriber_list: adjacent subscribers in top. server's list of subscribers |
| * @subscription_list: list of subscription objects for this subscriber |
| * @port_ref: object reference to port used to communicate with subscriber |
| * @swap: indicates if subscriber uses opposite endianness in its messages |
| */ |
| |
| struct subscriber { |
| u32 ref; |
| spinlock_t *lock; |
| struct list_head subscriber_list; |
| struct list_head subscription_list; |
| u32 port_ref; |
| int swap; |
| }; |
| |
| /** |
| * struct top_srv - TIPC network topology subscription service |
| * @user_ref: TIPC userid of subscription service |
| * @setup_port: reference to TIPC port that handles subscription requests |
| * @subscription_count: number of active subscriptions (not subscribers!) |
| * @subscriber_list: list of ports subscribing to service |
| * @lock: spinlock govering access to subscriber list |
| */ |
| |
| struct top_srv { |
| u32 user_ref; |
| u32 setup_port; |
| atomic_t subscription_count; |
| struct list_head subscriber_list; |
| spinlock_t lock; |
| }; |
| |
| static struct top_srv topsrv = { 0 }; |
| |
| /** |
| * htohl - convert value to endianness used by destination |
| * @in: value to convert |
| * @swap: non-zero if endianness must be reversed |
| * |
| * Returns converted value |
| */ |
| |
| static inline u32 htohl(u32 in, int swap) |
| { |
| char *c = (char *)∈ |
| |
| return swap ? ((c[3] << 3) + (c[2] << 2) + (c[1] << 1) + c[0]) : in; |
| } |
| |
| /** |
| * subscr_send_event - send a message containing a tipc_event to the subscriber |
| */ |
| |
| static void subscr_send_event(struct subscription *sub, |
| u32 found_lower, |
| u32 found_upper, |
| u32 event, |
| u32 port_ref, |
| u32 node) |
| { |
| struct iovec msg_sect; |
| |
| msg_sect.iov_base = (void *)&sub->evt; |
| msg_sect.iov_len = sizeof(struct tipc_event); |
| |
| sub->evt.event = htohl(event, sub->owner->swap); |
| sub->evt.found_lower = htohl(found_lower, sub->owner->swap); |
| sub->evt.found_upper = htohl(found_upper, sub->owner->swap); |
| sub->evt.port.ref = htohl(port_ref, sub->owner->swap); |
| sub->evt.port.node = htohl(node, sub->owner->swap); |
| tipc_send(sub->owner->port_ref, 1, &msg_sect); |
| } |
| |
| /** |
| * subscr_overlap - test for subscription overlap with the given values |
| * |
| * Returns 1 if there is overlap, otherwise 0. |
| */ |
| |
| int subscr_overlap(struct subscription *sub, |
| u32 found_lower, |
| u32 found_upper) |
| |
| { |
| if (found_lower < sub->seq.lower) |
| found_lower = sub->seq.lower; |
| if (found_upper > sub->seq.upper) |
| found_upper = sub->seq.upper; |
| if (found_lower > found_upper) |
| return 0; |
| return 1; |
| } |
| |
| /** |
| * subscr_report_overlap - issue event if there is subscription overlap |
| * |
| * Protected by nameseq.lock in name_table.c |
| */ |
| |
| void subscr_report_overlap(struct subscription *sub, |
| u32 found_lower, |
| u32 found_upper, |
| u32 event, |
| u32 port_ref, |
| u32 node, |
| int must) |
| { |
| dbg("Rep overlap %u:%u,%u<->%u,%u\n", sub->seq.type, sub->seq.lower, |
| sub->seq.upper, found_lower, found_upper); |
| if (!subscr_overlap(sub, found_lower, found_upper)) |
| return; |
| if (!must && (sub->filter != TIPC_SUB_PORTS)) |
| return; |
| subscr_send_event(sub, found_lower, found_upper, event, port_ref, node); |
| } |
| |
| /** |
| * subscr_timeout - subscription timeout has occurred |
| */ |
| |
| static void subscr_timeout(struct subscription *sub) |
| { |
| struct subscriber *subscriber; |
| u32 subscriber_ref; |
| |
| /* Validate subscriber reference (in case subscriber is terminating) */ |
| |
| subscriber_ref = sub->owner->ref; |
| subscriber = (struct subscriber *)ref_lock(subscriber_ref); |
| if (subscriber == NULL) |
| return; |
| |
| /* Unlink subscription from name table */ |
| |
| nametbl_unsubscribe(sub); |
| |
| /* Notify subscriber of timeout, then unlink subscription */ |
| |
| subscr_send_event(sub, |
| sub->evt.s.seq.lower, |
| sub->evt.s.seq.upper, |
| TIPC_SUBSCR_TIMEOUT, |
| 0, |
| 0); |
| list_del(&sub->subscription_list); |
| |
| /* Now destroy subscription */ |
| |
| ref_unlock(subscriber_ref); |
| k_term_timer(&sub->timer); |
| kfree(sub); |
| atomic_dec(&topsrv.subscription_count); |
| } |
| |
| /** |
| * subscr_terminate - terminate communication with a subscriber |
| * |
| * Called with subscriber locked. Routine must temporarily release this lock |
| * to enable subscription timeout routine(s) to finish without deadlocking; |
| * the lock is then reclaimed to allow caller to release it upon return. |
| * (This should work even in the unlikely event some other thread creates |
| * a new object reference in the interim that uses this lock; this routine will |
| * simply wait for it to be released, then claim it.) |
| */ |
| |
| static void subscr_terminate(struct subscriber *subscriber) |
| { |
| struct subscription *sub; |
| struct subscription *sub_temp; |
| |
| /* Invalidate subscriber reference */ |
| |
| ref_discard(subscriber->ref); |
| spin_unlock_bh(subscriber->lock); |
| |
| /* Destroy any existing subscriptions for subscriber */ |
| |
| list_for_each_entry_safe(sub, sub_temp, &subscriber->subscription_list, |
| subscription_list) { |
| if (sub->timeout != TIPC_WAIT_FOREVER) { |
| k_cancel_timer(&sub->timer); |
| k_term_timer(&sub->timer); |
| } |
| nametbl_unsubscribe(sub); |
| list_del(&sub->subscription_list); |
| dbg("Term: Removed sub %u,%u,%u from subscriber %x list\n", |
| sub->seq.type, sub->seq.lower, sub->seq.upper, subscriber); |
| kfree(sub); |
| atomic_dec(&topsrv.subscription_count); |
| } |
| |
| /* Sever connection to subscriber */ |
| |
| tipc_shutdown(subscriber->port_ref); |
| tipc_deleteport(subscriber->port_ref); |
| |
| /* Remove subscriber from topology server's subscriber list */ |
| |
| spin_lock_bh(&topsrv.lock); |
| list_del(&subscriber->subscriber_list); |
| spin_unlock_bh(&topsrv.lock); |
| |
| /* Now destroy subscriber */ |
| |
| spin_lock_bh(subscriber->lock); |
| kfree(subscriber); |
| } |
| |
| /** |
| * subscr_subscribe - create subscription for subscriber |
| * |
| * Called with subscriber locked |
| */ |
| |
| static void subscr_subscribe(struct tipc_subscr *s, |
| struct subscriber *subscriber) |
| { |
| struct subscription *sub; |
| |
| /* Refuse subscription if global limit exceeded */ |
| |
| if (atomic_read(&topsrv.subscription_count) >= tipc_max_subscriptions) { |
| warn("Failed: max %u subscriptions\n", tipc_max_subscriptions); |
| subscr_terminate(subscriber); |
| return; |
| } |
| |
| /* Allocate subscription object */ |
| |
| sub = kmalloc(sizeof(*sub), GFP_ATOMIC); |
| if (sub == NULL) { |
| warn("Memory squeeze; ignoring subscription\n"); |
| subscr_terminate(subscriber); |
| return; |
| } |
| |
| /* Determine/update subscriber's endianness */ |
| |
| if ((s->filter == TIPC_SUB_PORTS) || (s->filter == TIPC_SUB_SERVICE)) |
| subscriber->swap = 0; |
| else |
| subscriber->swap = 1; |
| |
| /* Initialize subscription object */ |
| |
| memset(sub, 0, sizeof(*sub)); |
| sub->seq.type = htohl(s->seq.type, subscriber->swap); |
| sub->seq.lower = htohl(s->seq.lower, subscriber->swap); |
| sub->seq.upper = htohl(s->seq.upper, subscriber->swap); |
| sub->timeout = htohl(s->timeout, subscriber->swap); |
| sub->filter = htohl(s->filter, subscriber->swap); |
| if ((((sub->filter != TIPC_SUB_PORTS) |
| && (sub->filter != TIPC_SUB_SERVICE))) |
| || (sub->seq.lower > sub->seq.upper)) { |
| warn("Rejecting illegal subscription %u,%u,%u\n", |
| sub->seq.type, sub->seq.lower, sub->seq.upper); |
| kfree(sub); |
| subscr_terminate(subscriber); |
| return; |
| } |
| memcpy(&sub->evt.s, s, sizeof(struct tipc_subscr)); |
| INIT_LIST_HEAD(&sub->subscription_list); |
| INIT_LIST_HEAD(&sub->nameseq_list); |
| list_add(&sub->subscription_list, &subscriber->subscription_list); |
| atomic_inc(&topsrv.subscription_count); |
| if (sub->timeout != TIPC_WAIT_FOREVER) { |
| k_init_timer(&sub->timer, |
| (Handler)subscr_timeout, (unsigned long)sub); |
| k_start_timer(&sub->timer, sub->timeout); |
| } |
| sub->owner = subscriber; |
| nametbl_subscribe(sub); |
| } |
| |
| /** |
| * subscr_conn_shutdown_event - handle termination request from subscriber |
| */ |
| |
| static void subscr_conn_shutdown_event(void *usr_handle, |
| u32 portref, |
| struct sk_buff **buf, |
| unsigned char const *data, |
| unsigned int size, |
| int reason) |
| { |
| struct subscriber *subscriber = ref_lock((u32)usr_handle); |
| spinlock_t *subscriber_lock; |
| |
| if (subscriber == NULL) |
| return; |
| |
| subscriber_lock = subscriber->lock; |
| subscr_terminate(subscriber); |
| spin_unlock_bh(subscriber_lock); |
| } |
| |
| /** |
| * subscr_conn_msg_event - handle new subscription request from subscriber |
| */ |
| |
| static void subscr_conn_msg_event(void *usr_handle, |
| u32 port_ref, |
| struct sk_buff **buf, |
| const unchar *data, |
| u32 size) |
| { |
| struct subscriber *subscriber = ref_lock((u32)usr_handle); |
| spinlock_t *subscriber_lock; |
| |
| if (subscriber == NULL) |
| return; |
| |
| subscriber_lock = subscriber->lock; |
| if (size != sizeof(struct tipc_subscr)) |
| subscr_terminate(subscriber); |
| else |
| subscr_subscribe((struct tipc_subscr *)data, subscriber); |
| |
| spin_unlock_bh(subscriber_lock); |
| } |
| |
| /** |
| * subscr_named_msg_event - handle request to establish a new subscriber |
| */ |
| |
| static void subscr_named_msg_event(void *usr_handle, |
| u32 port_ref, |
| struct sk_buff **buf, |
| const unchar *data, |
| u32 size, |
| u32 importance, |
| struct tipc_portid const *orig, |
| struct tipc_name_seq const *dest) |
| { |
| struct subscriber *subscriber; |
| struct iovec msg_sect = {0, 0}; |
| spinlock_t *subscriber_lock; |
| |
| dbg("subscr_named_msg_event: orig = %x own = %x,\n", |
| orig->node, tipc_own_addr); |
| if (size && (size != sizeof(struct tipc_subscr))) { |
| warn("Received tipc_subscr of invalid size\n"); |
| return; |
| } |
| |
| /* Create subscriber object */ |
| |
| subscriber = kmalloc(sizeof(struct subscriber), GFP_ATOMIC); |
| if (subscriber == NULL) { |
| warn("Memory squeeze; ignoring subscriber setup\n"); |
| return; |
| } |
| memset(subscriber, 0, sizeof(struct subscriber)); |
| INIT_LIST_HEAD(&subscriber->subscription_list); |
| INIT_LIST_HEAD(&subscriber->subscriber_list); |
| subscriber->ref = ref_acquire(subscriber, &subscriber->lock); |
| if (subscriber->ref == 0) { |
| warn("Failed to acquire subscriber reference\n"); |
| kfree(subscriber); |
| return; |
| } |
| |
| /* Establish a connection to subscriber */ |
| |
| tipc_createport(topsrv.user_ref, |
| (void *)subscriber->ref, |
| importance, |
| 0, |
| 0, |
| subscr_conn_shutdown_event, |
| 0, |
| 0, |
| subscr_conn_msg_event, |
| 0, |
| &subscriber->port_ref); |
| if (subscriber->port_ref == 0) { |
| warn("Memory squeeze; failed to create subscription port\n"); |
| ref_discard(subscriber->ref); |
| kfree(subscriber); |
| return; |
| } |
| tipc_connect2port(subscriber->port_ref, orig); |
| |
| |
| /* Add subscriber to topology server's subscriber list */ |
| |
| ref_lock(subscriber->ref); |
| spin_lock_bh(&topsrv.lock); |
| list_add(&subscriber->subscriber_list, &topsrv.subscriber_list); |
| spin_unlock_bh(&topsrv.lock); |
| |
| /* |
| * Subscribe now if message contains a subscription, |
| * otherwise send an empty response to complete connection handshaking |
| */ |
| |
| subscriber_lock = subscriber->lock; |
| if (size) |
| subscr_subscribe((struct tipc_subscr *)data, subscriber); |
| else |
| tipc_send(subscriber->port_ref, 1, &msg_sect); |
| |
| spin_unlock_bh(subscriber_lock); |
| } |
| |
| int subscr_start(void) |
| { |
| struct tipc_name_seq seq = {TIPC_TOP_SRV, TIPC_TOP_SRV, TIPC_TOP_SRV}; |
| int res = -1; |
| |
| memset(&topsrv, 0, sizeof (topsrv)); |
| topsrv.lock = SPIN_LOCK_UNLOCKED; |
| INIT_LIST_HEAD(&topsrv.subscriber_list); |
| |
| spin_lock_bh(&topsrv.lock); |
| res = tipc_attach(&topsrv.user_ref, 0, 0); |
| if (res) { |
| spin_unlock_bh(&topsrv.lock); |
| return res; |
| } |
| |
| res = tipc_createport(topsrv.user_ref, |
| 0, |
| TIPC_CRITICAL_IMPORTANCE, |
| 0, |
| 0, |
| 0, |
| 0, |
| subscr_named_msg_event, |
| 0, |
| 0, |
| &topsrv.setup_port); |
| if (res) |
| goto failed; |
| |
| res = nametbl_publish_rsv(topsrv.setup_port, TIPC_NODE_SCOPE, &seq); |
| if (res) |
| goto failed; |
| |
| spin_unlock_bh(&topsrv.lock); |
| return 0; |
| |
| failed: |
| err("Failed to create subscription service\n"); |
| tipc_detach(topsrv.user_ref); |
| topsrv.user_ref = 0; |
| spin_unlock_bh(&topsrv.lock); |
| return res; |
| } |
| |
| void subscr_stop(void) |
| { |
| struct subscriber *subscriber; |
| struct subscriber *subscriber_temp; |
| spinlock_t *subscriber_lock; |
| |
| if (topsrv.user_ref) { |
| tipc_deleteport(topsrv.setup_port); |
| list_for_each_entry_safe(subscriber, subscriber_temp, |
| &topsrv.subscriber_list, |
| subscriber_list) { |
| ref_lock(subscriber->ref); |
| subscriber_lock = subscriber->lock; |
| subscr_terminate(subscriber); |
| spin_unlock_bh(subscriber_lock); |
| } |
| tipc_detach(topsrv.user_ref); |
| topsrv.user_ref = 0; |
| } |
| } |
| |
| |
| int tipc_ispublished(struct tipc_name const *name) |
| { |
| u32 domain = 0; |
| |
| return(nametbl_translate(name->type, name->instance,&domain) != 0); |
| } |
| |