diff options
author | Lijun Chen <chenli@nortel.com> | 2006-10-17 00:59:42 -0400 |
---|---|---|
committer | David S. Miller <davem@sunset.davemloft.net> | 2006-10-18 22:55:22 -0400 |
commit | eb409460b1abec0e2a1f9c9d07019f4157a6d6bc (patch) | |
tree | 5402d4e64b1ad7f5e433cf7f222688402e8d7ad5 | |
parent | fc144deec6403c17e6d3f6a6574f701420f166ed (diff) |
[TIPC]: Added subscription cancellation capability
This patch allows a TIPC application to cancel an existing
topology service subscription by re-requesting the subscription
with the TIPC_SUB_CANCEL filter bit set. (All other bits of
the cancel request must match the original subscription request.)
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Per Liden <per.liden@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | include/linux/tipc.h | 1 | ||||
-rw-r--r-- | net/tipc/subscr.c | 99 |
2 files changed, 85 insertions, 15 deletions
diff --git a/include/linux/tipc.h b/include/linux/tipc.h index 243a15f54002..bea469455a0c 100644 --- a/include/linux/tipc.h +++ b/include/linux/tipc.h | |||
@@ -129,6 +129,7 @@ static inline unsigned int tipc_node(__u32 addr) | |||
129 | 129 | ||
130 | #define TIPC_SUB_PORTS 0x01 /* filter for port availability */ | 130 | #define TIPC_SUB_PORTS 0x01 /* filter for port availability */ |
131 | #define TIPC_SUB_SERVICE 0x02 /* filter for service availability */ | 131 | #define TIPC_SUB_SERVICE 0x02 /* filter for service availability */ |
132 | #define TIPC_SUB_CANCEL 0x04 /* cancel a subscription */ | ||
132 | #if 0 | 133 | #if 0 |
133 | /* The following filter options are not currently implemented */ | 134 | /* The following filter options are not currently implemented */ |
134 | #define TIPC_SUB_NO_BIND_EVTS 0x04 /* filter out "publish" events */ | 135 | #define TIPC_SUB_NO_BIND_EVTS 0x04 /* filter out "publish" events */ |
diff --git a/net/tipc/subscr.c b/net/tipc/subscr.c index c51600ba5f4a..7a918f12a5df 100644 --- a/net/tipc/subscr.c +++ b/net/tipc/subscr.c | |||
@@ -155,7 +155,7 @@ void tipc_subscr_report_overlap(struct subscription *sub, | |||
155 | sub->seq.upper, found_lower, found_upper); | 155 | sub->seq.upper, found_lower, found_upper); |
156 | if (!tipc_subscr_overlap(sub, found_lower, found_upper)) | 156 | if (!tipc_subscr_overlap(sub, found_lower, found_upper)) |
157 | return; | 157 | return; |
158 | if (!must && (sub->filter != TIPC_SUB_PORTS)) | 158 | if (!must && !(sub->filter & TIPC_SUB_PORTS)) |
159 | return; | 159 | return; |
160 | subscr_send_event(sub, found_lower, found_upper, event, port_ref, node); | 160 | subscr_send_event(sub, found_lower, found_upper, event, port_ref, node); |
161 | } | 161 | } |
@@ -176,6 +176,13 @@ static void subscr_timeout(struct subscription *sub) | |||
176 | if (subscriber == NULL) | 176 | if (subscriber == NULL) |
177 | return; | 177 | return; |
178 | 178 | ||
179 | /* Validate timeout (in case subscription is being cancelled) */ | ||
180 | |||
181 | if (sub->timeout == TIPC_WAIT_FOREVER) { | ||
182 | tipc_ref_unlock(subscriber_ref); | ||
183 | return; | ||
184 | } | ||
185 | |||
179 | /* Unlink subscription from name table */ | 186 | /* Unlink subscription from name table */ |
180 | 187 | ||
181 | tipc_nametbl_unsubscribe(sub); | 188 | tipc_nametbl_unsubscribe(sub); |
@@ -199,6 +206,20 @@ static void subscr_timeout(struct subscription *sub) | |||
199 | } | 206 | } |
200 | 207 | ||
201 | /** | 208 | /** |
209 | * subscr_del - delete a subscription within a subscription list | ||
210 | * | ||
211 | * Called with subscriber locked. | ||
212 | */ | ||
213 | |||
214 | static void subscr_del(struct subscription *sub) | ||
215 | { | ||
216 | tipc_nametbl_unsubscribe(sub); | ||
217 | list_del(&sub->subscription_list); | ||
218 | kfree(sub); | ||
219 | atomic_dec(&topsrv.subscription_count); | ||
220 | } | ||
221 | |||
222 | /** | ||
202 | * subscr_terminate - terminate communication with a subscriber | 223 | * subscr_terminate - terminate communication with a subscriber |
203 | * | 224 | * |
204 | * Called with subscriber locked. Routine must temporarily release this lock | 225 | * Called with subscriber locked. Routine must temporarily release this lock |
@@ -227,12 +248,9 @@ static void subscr_terminate(struct subscriber *subscriber) | |||
227 | k_cancel_timer(&sub->timer); | 248 | k_cancel_timer(&sub->timer); |
228 | k_term_timer(&sub->timer); | 249 | k_term_timer(&sub->timer); |
229 | } | 250 | } |
230 | tipc_nametbl_unsubscribe(sub); | 251 | dbg("Term: Removing sub %u,%u,%u from subscriber %x list\n", |
231 | list_del(&sub->subscription_list); | ||
232 | dbg("Term: Removed sub %u,%u,%u from subscriber %x list\n", | ||
233 | sub->seq.type, sub->seq.lower, sub->seq.upper, subscriber); | 252 | sub->seq.type, sub->seq.lower, sub->seq.upper, subscriber); |
234 | kfree(sub); | 253 | subscr_del(sub); |
235 | atomic_dec(&topsrv.subscription_count); | ||
236 | } | 254 | } |
237 | 255 | ||
238 | /* Sever connection to subscriber */ | 256 | /* Sever connection to subscriber */ |
@@ -253,6 +271,49 @@ static void subscr_terminate(struct subscriber *subscriber) | |||
253 | } | 271 | } |
254 | 272 | ||
255 | /** | 273 | /** |
274 | * subscr_cancel - handle subscription cancellation request | ||
275 | * | ||
276 | * Called with subscriber locked. Routine must temporarily release this lock | ||
277 | * to enable the subscription timeout routine to finish without deadlocking; | ||
278 | * the lock is then reclaimed to allow caller to release it upon return. | ||
279 | * | ||
280 | * Note that fields of 's' use subscriber's endianness! | ||
281 | */ | ||
282 | |||
283 | static void subscr_cancel(struct tipc_subscr *s, | ||
284 | struct subscriber *subscriber) | ||
285 | { | ||
286 | struct subscription *sub; | ||
287 | struct subscription *sub_temp; | ||
288 | int found = 0; | ||
289 | |||
290 | /* Find first matching subscription, exit if not found */ | ||
291 | |||
292 | list_for_each_entry_safe(sub, sub_temp, &subscriber->subscription_list, | ||
293 | subscription_list) { | ||
294 | if (!memcmp(s, &sub->evt.s, sizeof(struct tipc_subscr))) { | ||
295 | found = 1; | ||
296 | break; | ||
297 | } | ||
298 | } | ||
299 | if (!found) | ||
300 | return; | ||
301 | |||
302 | /* Cancel subscription timer (if used), then delete subscription */ | ||
303 | |||
304 | if (sub->timeout != TIPC_WAIT_FOREVER) { | ||
305 | sub->timeout = TIPC_WAIT_FOREVER; | ||
306 | spin_unlock_bh(subscriber->lock); | ||
307 | k_cancel_timer(&sub->timer); | ||
308 | k_term_timer(&sub->timer); | ||
309 | spin_lock_bh(subscriber->lock); | ||
310 | } | ||
311 | dbg("Cancel: removing sub %u,%u,%u from subscriber %x list\n", | ||
312 | sub->seq.type, sub->seq.lower, sub->seq.upper, subscriber); | ||
313 | subscr_del(sub); | ||
314 | } | ||
315 | |||
316 | /** | ||
256 | * subscr_subscribe - create subscription for subscriber | 317 | * subscr_subscribe - create subscription for subscriber |
257 | * | 318 | * |
258 | * Called with subscriber locked | 319 | * Called with subscriber locked |
@@ -263,6 +324,21 @@ static void subscr_subscribe(struct tipc_subscr *s, | |||
263 | { | 324 | { |
264 | struct subscription *sub; | 325 | struct subscription *sub; |
265 | 326 | ||
327 | /* Determine/update subscriber's endianness */ | ||
328 | |||
329 | if (s->filter & (TIPC_SUB_PORTS | TIPC_SUB_SERVICE)) | ||
330 | subscriber->swap = 0; | ||
331 | else | ||
332 | subscriber->swap = 1; | ||
333 | |||
334 | /* Detect & process a subscription cancellation request */ | ||
335 | |||
336 | if (s->filter & htohl(TIPC_SUB_CANCEL, subscriber->swap)) { | ||
337 | s->filter &= ~htohl(TIPC_SUB_CANCEL, subscriber->swap); | ||
338 | subscr_cancel(s, subscriber); | ||
339 | return; | ||
340 | } | ||
341 | |||
266 | /* Refuse subscription if global limit exceeded */ | 342 | /* Refuse subscription if global limit exceeded */ |
267 | 343 | ||
268 | if (atomic_read(&topsrv.subscription_count) >= tipc_max_subscriptions) { | 344 | if (atomic_read(&topsrv.subscription_count) >= tipc_max_subscriptions) { |
@@ -281,13 +357,6 @@ static void subscr_subscribe(struct tipc_subscr *s, | |||
281 | return; | 357 | return; |
282 | } | 358 | } |
283 | 359 | ||
284 | /* Determine/update subscriber's endianness */ | ||
285 | |||
286 | if ((s->filter == TIPC_SUB_PORTS) || (s->filter == TIPC_SUB_SERVICE)) | ||
287 | subscriber->swap = 0; | ||
288 | else | ||
289 | subscriber->swap = 1; | ||
290 | |||
291 | /* Initialize subscription object */ | 360 | /* Initialize subscription object */ |
292 | 361 | ||
293 | memset(sub, 0, sizeof(*sub)); | 362 | memset(sub, 0, sizeof(*sub)); |
@@ -296,8 +365,8 @@ static void subscr_subscribe(struct tipc_subscr *s, | |||
296 | sub->seq.upper = htohl(s->seq.upper, subscriber->swap); | 365 | sub->seq.upper = htohl(s->seq.upper, subscriber->swap); |
297 | sub->timeout = htohl(s->timeout, subscriber->swap); | 366 | sub->timeout = htohl(s->timeout, subscriber->swap); |
298 | sub->filter = htohl(s->filter, subscriber->swap); | 367 | sub->filter = htohl(s->filter, subscriber->swap); |
299 | if ((((sub->filter != TIPC_SUB_PORTS) | 368 | if ((!(sub->filter & TIPC_SUB_PORTS) |
300 | && (sub->filter != TIPC_SUB_SERVICE))) | 369 | == !(sub->filter & TIPC_SUB_SERVICE)) |
301 | || (sub->seq.lower > sub->seq.upper)) { | 370 | || (sub->seq.lower > sub->seq.upper)) { |
302 | warn("Subscription rejected, illegal request\n"); | 371 | warn("Subscription rejected, illegal request\n"); |
303 | kfree(sub); | 372 | kfree(sub); |