1 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
2 /*
3 * Copyright (c) 2015, Sony Mobile Communications Inc.
4 * Copyright (c) 2013, The Linux Foundation. All rights reserved.
5 * Copyright (c) 2020, Linaro Ltd.
6 */
7
8 #include <linux/module.h>
9 #include <linux/qrtr.h>
10 #include <linux/workqueue.h>
11 #include <net/sock.h>
12
13 #include "qrtr.h"
14
15 #include <trace/events/sock.h>
16 #define CREATE_TRACE_POINTS
17 #include <trace/events/qrtr.h>
18
19 static DEFINE_XARRAY(nodes);
20
21 static struct {
22 struct socket *sock;
23 struct sockaddr_qrtr bcast_sq;
24 struct list_head lookups;
25 struct workqueue_struct *workqueue;
26 struct work_struct work;
27 int local_node;
28 } qrtr_ns;
29
30 static const char * const qrtr_ctrl_pkt_strings[] = {
31 [QRTR_TYPE_HELLO] = "hello",
32 [QRTR_TYPE_BYE] = "bye",
33 [QRTR_TYPE_NEW_SERVER] = "new-server",
34 [QRTR_TYPE_DEL_SERVER] = "del-server",
35 [QRTR_TYPE_DEL_CLIENT] = "del-client",
36 [QRTR_TYPE_RESUME_TX] = "resume-tx",
37 [QRTR_TYPE_EXIT] = "exit",
38 [QRTR_TYPE_PING] = "ping",
39 [QRTR_TYPE_NEW_LOOKUP] = "new-lookup",
40 [QRTR_TYPE_DEL_LOOKUP] = "del-lookup",
41 };
42
43 struct qrtr_server_filter {
44 unsigned int service;
45 unsigned int instance;
46 unsigned int ifilter;
47 };
48
49 struct qrtr_lookup {
50 unsigned int service;
51 unsigned int instance;
52
53 struct sockaddr_qrtr sq;
54 struct list_head li;
55 };
56
57 struct qrtr_server {
58 unsigned int service;
59 unsigned int instance;
60
61 unsigned int node;
62 unsigned int port;
63
64 struct list_head qli;
65 };
66
67 struct qrtr_node {
68 unsigned int id;
69 struct xarray servers;
70 };
71
node_get(unsigned int node_id)72 static struct qrtr_node *node_get(unsigned int node_id)
73 {
74 struct qrtr_node *node;
75
76 node = xa_load(&nodes, node_id);
77 if (node)
78 return node;
79
80 /* If node didn't exist, allocate and insert it to the tree */
81 node = kzalloc(sizeof(*node), GFP_KERNEL);
82 if (!node)
83 return NULL;
84
85 node->id = node_id;
86 xa_init(&node->servers);
87
88 if (xa_store(&nodes, node_id, node, GFP_KERNEL)) {
89 kfree(node);
90 return NULL;
91 }
92
93 return node;
94 }
95
server_match(const struct qrtr_server * srv,const struct qrtr_server_filter * f)96 static int server_match(const struct qrtr_server *srv,
97 const struct qrtr_server_filter *f)
98 {
99 unsigned int ifilter = f->ifilter;
100
101 if (f->service != 0 && srv->service != f->service)
102 return 0;
103 if (!ifilter && f->instance)
104 ifilter = ~0;
105
106 return (srv->instance & ifilter) == f->instance;
107 }
108
service_announce_new(struct sockaddr_qrtr * dest,struct qrtr_server * srv)109 static int service_announce_new(struct sockaddr_qrtr *dest,
110 struct qrtr_server *srv)
111 {
112 struct qrtr_ctrl_pkt pkt;
113 struct msghdr msg = { };
114 struct kvec iv;
115
116 trace_qrtr_ns_service_announce_new(srv->service, srv->instance,
117 srv->node, srv->port);
118
119 iv.iov_base = &pkt;
120 iv.iov_len = sizeof(pkt);
121
122 memset(&pkt, 0, sizeof(pkt));
123 pkt.cmd = cpu_to_le32(QRTR_TYPE_NEW_SERVER);
124 pkt.server.service = cpu_to_le32(srv->service);
125 pkt.server.instance = cpu_to_le32(srv->instance);
126 pkt.server.node = cpu_to_le32(srv->node);
127 pkt.server.port = cpu_to_le32(srv->port);
128
129 msg.msg_name = (struct sockaddr *)dest;
130 msg.msg_namelen = sizeof(*dest);
131
132 return kernel_sendmsg(qrtr_ns.sock, &msg, &iv, 1, sizeof(pkt));
133 }
134
service_announce_del(struct sockaddr_qrtr * dest,struct qrtr_server * srv)135 static int service_announce_del(struct sockaddr_qrtr *dest,
136 struct qrtr_server *srv)
137 {
138 struct qrtr_ctrl_pkt pkt;
139 struct msghdr msg = { };
140 struct kvec iv;
141 int ret;
142
143 trace_qrtr_ns_service_announce_del(srv->service, srv->instance,
144 srv->node, srv->port);
145
146 iv.iov_base = &pkt;
147 iv.iov_len = sizeof(pkt);
148
149 memset(&pkt, 0, sizeof(pkt));
150 pkt.cmd = cpu_to_le32(QRTR_TYPE_DEL_SERVER);
151 pkt.server.service = cpu_to_le32(srv->service);
152 pkt.server.instance = cpu_to_le32(srv->instance);
153 pkt.server.node = cpu_to_le32(srv->node);
154 pkt.server.port = cpu_to_le32(srv->port);
155
156 msg.msg_name = (struct sockaddr *)dest;
157 msg.msg_namelen = sizeof(*dest);
158
159 ret = kernel_sendmsg(qrtr_ns.sock, &msg, &iv, 1, sizeof(pkt));
160 if (ret < 0)
161 pr_err("failed to announce del service\n");
162
163 return ret;
164 }
165
lookup_notify(struct sockaddr_qrtr * to,struct qrtr_server * srv,bool new)166 static void lookup_notify(struct sockaddr_qrtr *to, struct qrtr_server *srv,
167 bool new)
168 {
169 struct qrtr_ctrl_pkt pkt;
170 struct msghdr msg = { };
171 struct kvec iv;
172 int ret;
173
174 iv.iov_base = &pkt;
175 iv.iov_len = sizeof(pkt);
176
177 memset(&pkt, 0, sizeof(pkt));
178 pkt.cmd = new ? cpu_to_le32(QRTR_TYPE_NEW_SERVER) :
179 cpu_to_le32(QRTR_TYPE_DEL_SERVER);
180 if (srv) {
181 pkt.server.service = cpu_to_le32(srv->service);
182 pkt.server.instance = cpu_to_le32(srv->instance);
183 pkt.server.node = cpu_to_le32(srv->node);
184 pkt.server.port = cpu_to_le32(srv->port);
185 }
186
187 msg.msg_name = (struct sockaddr *)to;
188 msg.msg_namelen = sizeof(*to);
189
190 ret = kernel_sendmsg(qrtr_ns.sock, &msg, &iv, 1, sizeof(pkt));
191 if (ret < 0)
192 pr_err("failed to send lookup notification\n");
193 }
194
announce_servers(struct sockaddr_qrtr * sq)195 static int announce_servers(struct sockaddr_qrtr *sq)
196 {
197 struct qrtr_server *srv;
198 struct qrtr_node *node;
199 unsigned long index;
200 int ret;
201
202 node = node_get(qrtr_ns.local_node);
203 if (!node)
204 return 0;
205
206 /* Announce the list of servers registered in this node */
207 xa_for_each(&node->servers, index, srv) {
208 ret = service_announce_new(sq, srv);
209 if (ret < 0) {
210 pr_err("failed to announce new service\n");
211 return ret;
212 }
213 }
214 return 0;
215 }
216
server_add(unsigned int service,unsigned int instance,unsigned int node_id,unsigned int port)217 static struct qrtr_server *server_add(unsigned int service,
218 unsigned int instance,
219 unsigned int node_id,
220 unsigned int port)
221 {
222 struct qrtr_server *srv;
223 struct qrtr_server *old;
224 struct qrtr_node *node;
225
226 if (!service || !port)
227 return NULL;
228
229 srv = kzalloc(sizeof(*srv), GFP_KERNEL);
230 if (!srv)
231 return NULL;
232
233 srv->service = service;
234 srv->instance = instance;
235 srv->node = node_id;
236 srv->port = port;
237
238 node = node_get(node_id);
239 if (!node)
240 goto err;
241
242 /* Delete the old server on the same port */
243 old = xa_store(&node->servers, port, srv, GFP_KERNEL);
244 if (old) {
245 if (xa_is_err(old)) {
246 pr_err("failed to add server [0x%x:0x%x] ret:%d\n",
247 srv->service, srv->instance, xa_err(old));
248 goto err;
249 } else {
250 kfree(old);
251 }
252 }
253
254 trace_qrtr_ns_server_add(srv->service, srv->instance,
255 srv->node, srv->port);
256
257 return srv;
258
259 err:
260 kfree(srv);
261 return NULL;
262 }
263
server_del(struct qrtr_node * node,unsigned int port,bool bcast)264 static int server_del(struct qrtr_node *node, unsigned int port, bool bcast)
265 {
266 struct qrtr_lookup *lookup;
267 struct qrtr_server *srv;
268 struct list_head *li;
269
270 srv = xa_load(&node->servers, port);
271 if (!srv)
272 return -ENOENT;
273
274 xa_erase(&node->servers, port);
275
276 /* Broadcast the removal of local servers */
277 if (srv->node == qrtr_ns.local_node && bcast)
278 service_announce_del(&qrtr_ns.bcast_sq, srv);
279
280 /* Announce the service's disappearance to observers */
281 list_for_each(li, &qrtr_ns.lookups) {
282 lookup = container_of(li, struct qrtr_lookup, li);
283 if (lookup->service && lookup->service != srv->service)
284 continue;
285 if (lookup->instance && lookup->instance != srv->instance)
286 continue;
287
288 lookup_notify(&lookup->sq, srv, false);
289 }
290
291 kfree(srv);
292
293 return 0;
294 }
295
say_hello(struct sockaddr_qrtr * dest)296 static int say_hello(struct sockaddr_qrtr *dest)
297 {
298 struct qrtr_ctrl_pkt pkt;
299 struct msghdr msg = { };
300 struct kvec iv;
301 int ret;
302
303 iv.iov_base = &pkt;
304 iv.iov_len = sizeof(pkt);
305
306 memset(&pkt, 0, sizeof(pkt));
307 pkt.cmd = cpu_to_le32(QRTR_TYPE_HELLO);
308
309 msg.msg_name = (struct sockaddr *)dest;
310 msg.msg_namelen = sizeof(*dest);
311
312 ret = kernel_sendmsg(qrtr_ns.sock, &msg, &iv, 1, sizeof(pkt));
313 if (ret < 0)
314 pr_err("failed to send hello msg\n");
315
316 return ret;
317 }
318
319 /* Announce the list of servers registered on the local node */
ctrl_cmd_hello(struct sockaddr_qrtr * sq)320 static int ctrl_cmd_hello(struct sockaddr_qrtr *sq)
321 {
322 int ret;
323
324 ret = say_hello(sq);
325 if (ret < 0)
326 return ret;
327
328 return announce_servers(sq);
329 }
330
ctrl_cmd_bye(struct sockaddr_qrtr * from)331 static int ctrl_cmd_bye(struct sockaddr_qrtr *from)
332 {
333 struct qrtr_node *local_node;
334 struct qrtr_ctrl_pkt pkt;
335 struct qrtr_server *srv;
336 struct sockaddr_qrtr sq;
337 struct msghdr msg = { };
338 struct qrtr_node *node;
339 unsigned long index;
340 struct kvec iv;
341 int ret;
342
343 iv.iov_base = &pkt;
344 iv.iov_len = sizeof(pkt);
345
346 node = node_get(from->sq_node);
347 if (!node)
348 return 0;
349
350 /* Advertise removal of this client to all servers of remote node */
351 xa_for_each(&node->servers, index, srv)
352 server_del(node, srv->port, true);
353
354 /* Advertise the removal of this client to all local servers */
355 local_node = node_get(qrtr_ns.local_node);
356 if (!local_node)
357 return 0;
358
359 memset(&pkt, 0, sizeof(pkt));
360 pkt.cmd = cpu_to_le32(QRTR_TYPE_BYE);
361 pkt.client.node = cpu_to_le32(from->sq_node);
362
363 xa_for_each(&local_node->servers, index, srv) {
364 sq.sq_family = AF_QIPCRTR;
365 sq.sq_node = srv->node;
366 sq.sq_port = srv->port;
367
368 msg.msg_name = (struct sockaddr *)&sq;
369 msg.msg_namelen = sizeof(sq);
370
371 ret = kernel_sendmsg(qrtr_ns.sock, &msg, &iv, 1, sizeof(pkt));
372 if (ret < 0) {
373 pr_err("failed to send bye cmd\n");
374 return ret;
375 }
376 }
377 return 0;
378 }
379
ctrl_cmd_del_client(struct sockaddr_qrtr * from,unsigned int node_id,unsigned int port)380 static int ctrl_cmd_del_client(struct sockaddr_qrtr *from,
381 unsigned int node_id, unsigned int port)
382 {
383 struct qrtr_node *local_node;
384 struct qrtr_lookup *lookup;
385 struct qrtr_ctrl_pkt pkt;
386 struct msghdr msg = { };
387 struct qrtr_server *srv;
388 struct sockaddr_qrtr sq;
389 struct qrtr_node *node;
390 struct list_head *tmp;
391 struct list_head *li;
392 unsigned long index;
393 struct kvec iv;
394 int ret;
395
396 iv.iov_base = &pkt;
397 iv.iov_len = sizeof(pkt);
398
399 /* Don't accept spoofed messages */
400 if (from->sq_node != node_id)
401 return -EINVAL;
402
403 /* Local DEL_CLIENT messages comes from the port being closed */
404 if (from->sq_node == qrtr_ns.local_node && from->sq_port != port)
405 return -EINVAL;
406
407 /* Remove any lookups by this client */
408 list_for_each_safe(li, tmp, &qrtr_ns.lookups) {
409 lookup = container_of(li, struct qrtr_lookup, li);
410 if (lookup->sq.sq_node != node_id)
411 continue;
412 if (lookup->sq.sq_port != port)
413 continue;
414
415 list_del(&lookup->li);
416 kfree(lookup);
417 }
418
419 /* Remove the server belonging to this port but don't broadcast
420 * DEL_SERVER. Neighbours would've already removed the server belonging
421 * to this port due to the DEL_CLIENT broadcast from qrtr_port_remove().
422 */
423 node = node_get(node_id);
424 if (node)
425 server_del(node, port, false);
426
427 /* Advertise the removal of this client to all local servers */
428 local_node = node_get(qrtr_ns.local_node);
429 if (!local_node)
430 return 0;
431
432 memset(&pkt, 0, sizeof(pkt));
433 pkt.cmd = cpu_to_le32(QRTR_TYPE_DEL_CLIENT);
434 pkt.client.node = cpu_to_le32(node_id);
435 pkt.client.port = cpu_to_le32(port);
436
437 xa_for_each(&local_node->servers, index, srv) {
438 sq.sq_family = AF_QIPCRTR;
439 sq.sq_node = srv->node;
440 sq.sq_port = srv->port;
441
442 msg.msg_name = (struct sockaddr *)&sq;
443 msg.msg_namelen = sizeof(sq);
444
445 ret = kernel_sendmsg(qrtr_ns.sock, &msg, &iv, 1, sizeof(pkt));
446 if (ret < 0) {
447 pr_err("failed to send del client cmd\n");
448 return ret;
449 }
450 }
451 return 0;
452 }
453
ctrl_cmd_new_server(struct sockaddr_qrtr * from,unsigned int service,unsigned int instance,unsigned int node_id,unsigned int port)454 static int ctrl_cmd_new_server(struct sockaddr_qrtr *from,
455 unsigned int service, unsigned int instance,
456 unsigned int node_id, unsigned int port)
457 {
458 struct qrtr_lookup *lookup;
459 struct qrtr_server *srv;
460 struct list_head *li;
461 int ret = 0;
462
463 /* Ignore specified node and port for local servers */
464 if (from->sq_node == qrtr_ns.local_node) {
465 node_id = from->sq_node;
466 port = from->sq_port;
467 }
468
469 srv = server_add(service, instance, node_id, port);
470 if (!srv)
471 return -EINVAL;
472
473 if (srv->node == qrtr_ns.local_node) {
474 ret = service_announce_new(&qrtr_ns.bcast_sq, srv);
475 if (ret < 0) {
476 pr_err("failed to announce new service\n");
477 return ret;
478 }
479 }
480
481 /* Notify any potential lookups about the new server */
482 list_for_each(li, &qrtr_ns.lookups) {
483 lookup = container_of(li, struct qrtr_lookup, li);
484 if (lookup->service && lookup->service != service)
485 continue;
486 if (lookup->instance && lookup->instance != instance)
487 continue;
488
489 lookup_notify(&lookup->sq, srv, true);
490 }
491
492 return ret;
493 }
494
ctrl_cmd_del_server(struct sockaddr_qrtr * from,unsigned int service,unsigned int instance,unsigned int node_id,unsigned int port)495 static int ctrl_cmd_del_server(struct sockaddr_qrtr *from,
496 unsigned int service, unsigned int instance,
497 unsigned int node_id, unsigned int port)
498 {
499 struct qrtr_node *node;
500
501 /* Ignore specified node and port for local servers*/
502 if (from->sq_node == qrtr_ns.local_node) {
503 node_id = from->sq_node;
504 port = from->sq_port;
505 }
506
507 /* Local servers may only unregister themselves */
508 if (from->sq_node == qrtr_ns.local_node && from->sq_port != port)
509 return -EINVAL;
510
511 node = node_get(node_id);
512 if (!node)
513 return -ENOENT;
514
515 server_del(node, port, true);
516
517 return 0;
518 }
519
ctrl_cmd_new_lookup(struct sockaddr_qrtr * from,unsigned int service,unsigned int instance)520 static int ctrl_cmd_new_lookup(struct sockaddr_qrtr *from,
521 unsigned int service, unsigned int instance)
522 {
523 struct qrtr_server_filter filter;
524 struct qrtr_lookup *lookup;
525 struct qrtr_server *srv;
526 struct qrtr_node *node;
527 unsigned long node_idx;
528 unsigned long srv_idx;
529
530 /* Accept only local observers */
531 if (from->sq_node != qrtr_ns.local_node)
532 return -EINVAL;
533
534 lookup = kzalloc(sizeof(*lookup), GFP_KERNEL);
535 if (!lookup)
536 return -ENOMEM;
537
538 lookup->sq = *from;
539 lookup->service = service;
540 lookup->instance = instance;
541 list_add_tail(&lookup->li, &qrtr_ns.lookups);
542
543 memset(&filter, 0, sizeof(filter));
544 filter.service = service;
545 filter.instance = instance;
546
547 xa_for_each(&nodes, node_idx, node) {
548 xa_for_each(&node->servers, srv_idx, srv) {
549 if (!server_match(srv, &filter))
550 continue;
551
552 lookup_notify(from, srv, true);
553 }
554 }
555
556 /* Empty notification, to indicate end of listing */
557 lookup_notify(from, NULL, true);
558
559 return 0;
560 }
561
ctrl_cmd_del_lookup(struct sockaddr_qrtr * from,unsigned int service,unsigned int instance)562 static void ctrl_cmd_del_lookup(struct sockaddr_qrtr *from,
563 unsigned int service, unsigned int instance)
564 {
565 struct qrtr_lookup *lookup;
566 struct list_head *tmp;
567 struct list_head *li;
568
569 list_for_each_safe(li, tmp, &qrtr_ns.lookups) {
570 lookup = container_of(li, struct qrtr_lookup, li);
571 if (lookup->sq.sq_node != from->sq_node)
572 continue;
573 if (lookup->sq.sq_port != from->sq_port)
574 continue;
575 if (lookup->service != service)
576 continue;
577 if (lookup->instance && lookup->instance != instance)
578 continue;
579
580 list_del(&lookup->li);
581 kfree(lookup);
582 }
583 }
584
qrtr_ns_worker(struct work_struct * work)585 static void qrtr_ns_worker(struct work_struct *work)
586 {
587 const struct qrtr_ctrl_pkt *pkt;
588 size_t recv_buf_size = 4096;
589 struct sockaddr_qrtr sq;
590 struct msghdr msg = { };
591 unsigned int cmd;
592 ssize_t msglen;
593 void *recv_buf;
594 struct kvec iv;
595 int ret;
596
597 msg.msg_name = (struct sockaddr *)&sq;
598 msg.msg_namelen = sizeof(sq);
599
600 recv_buf = kzalloc(recv_buf_size, GFP_KERNEL);
601 if (!recv_buf)
602 return;
603
604 for (;;) {
605 iv.iov_base = recv_buf;
606 iv.iov_len = recv_buf_size;
607
608 msglen = kernel_recvmsg(qrtr_ns.sock, &msg, &iv, 1,
609 iv.iov_len, MSG_DONTWAIT);
610
611 if (msglen == -EAGAIN)
612 break;
613
614 if (msglen < 0) {
615 pr_err("error receiving packet: %zd\n", msglen);
616 break;
617 }
618
619 pkt = recv_buf;
620 cmd = le32_to_cpu(pkt->cmd);
621 if (cmd < ARRAY_SIZE(qrtr_ctrl_pkt_strings) &&
622 qrtr_ctrl_pkt_strings[cmd])
623 trace_qrtr_ns_message(qrtr_ctrl_pkt_strings[cmd],
624 sq.sq_node, sq.sq_port);
625
626 ret = 0;
627 switch (cmd) {
628 case QRTR_TYPE_HELLO:
629 ret = ctrl_cmd_hello(&sq);
630 break;
631 case QRTR_TYPE_BYE:
632 ret = ctrl_cmd_bye(&sq);
633 break;
634 case QRTR_TYPE_DEL_CLIENT:
635 ret = ctrl_cmd_del_client(&sq,
636 le32_to_cpu(pkt->client.node),
637 le32_to_cpu(pkt->client.port));
638 break;
639 case QRTR_TYPE_NEW_SERVER:
640 ret = ctrl_cmd_new_server(&sq,
641 le32_to_cpu(pkt->server.service),
642 le32_to_cpu(pkt->server.instance),
643 le32_to_cpu(pkt->server.node),
644 le32_to_cpu(pkt->server.port));
645 break;
646 case QRTR_TYPE_DEL_SERVER:
647 ret = ctrl_cmd_del_server(&sq,
648 le32_to_cpu(pkt->server.service),
649 le32_to_cpu(pkt->server.instance),
650 le32_to_cpu(pkt->server.node),
651 le32_to_cpu(pkt->server.port));
652 break;
653 case QRTR_TYPE_EXIT:
654 case QRTR_TYPE_PING:
655 case QRTR_TYPE_RESUME_TX:
656 break;
657 case QRTR_TYPE_NEW_LOOKUP:
658 ret = ctrl_cmd_new_lookup(&sq,
659 le32_to_cpu(pkt->server.service),
660 le32_to_cpu(pkt->server.instance));
661 break;
662 case QRTR_TYPE_DEL_LOOKUP:
663 ctrl_cmd_del_lookup(&sq,
664 le32_to_cpu(pkt->server.service),
665 le32_to_cpu(pkt->server.instance));
666 break;
667 }
668
669 if (ret < 0)
670 pr_err("failed while handling packet from %d:%d",
671 sq.sq_node, sq.sq_port);
672 }
673
674 kfree(recv_buf);
675 }
676
qrtr_ns_data_ready(struct sock * sk)677 static void qrtr_ns_data_ready(struct sock *sk)
678 {
679 trace_sk_data_ready(sk);
680
681 queue_work(qrtr_ns.workqueue, &qrtr_ns.work);
682 }
683
qrtr_ns_init(void)684 int qrtr_ns_init(void)
685 {
686 struct sockaddr_qrtr sq;
687 int ret;
688
689 INIT_LIST_HEAD(&qrtr_ns.lookups);
690 INIT_WORK(&qrtr_ns.work, qrtr_ns_worker);
691
692 ret = sock_create_kern(&init_net, AF_QIPCRTR, SOCK_DGRAM,
693 PF_QIPCRTR, &qrtr_ns.sock);
694 if (ret < 0)
695 return ret;
696
697 ret = kernel_getsockname(qrtr_ns.sock, (struct sockaddr *)&sq);
698 if (ret < 0) {
699 pr_err("failed to get socket name\n");
700 goto err_sock;
701 }
702
703 qrtr_ns.workqueue = alloc_ordered_workqueue("qrtr_ns_handler", 0);
704 if (!qrtr_ns.workqueue) {
705 ret = -ENOMEM;
706 goto err_sock;
707 }
708
709 qrtr_ns.sock->sk->sk_data_ready = qrtr_ns_data_ready;
710
711 sq.sq_port = QRTR_PORT_CTRL;
712 qrtr_ns.local_node = sq.sq_node;
713
714 ret = kernel_bind(qrtr_ns.sock, (struct sockaddr *)&sq, sizeof(sq));
715 if (ret < 0) {
716 pr_err("failed to bind to socket\n");
717 goto err_wq;
718 }
719
720 qrtr_ns.bcast_sq.sq_family = AF_QIPCRTR;
721 qrtr_ns.bcast_sq.sq_node = QRTR_NODE_BCAST;
722 qrtr_ns.bcast_sq.sq_port = QRTR_PORT_CTRL;
723
724 ret = say_hello(&qrtr_ns.bcast_sq);
725 if (ret < 0)
726 goto err_wq;
727
728 /* As the qrtr ns socket owner and creator is the same module, we have
729 * to decrease the qrtr module reference count to guarantee that it
730 * remains zero after the ns socket is created, otherwise, executing
731 * "rmmod" command is unable to make the qrtr module deleted after the
732 * qrtr module is inserted successfully.
733 *
734 * However, the reference count is increased twice in
735 * sock_create_kern(): one is to increase the reference count of owner
736 * of qrtr socket's proto_ops struct; another is to increment the
737 * reference count of owner of qrtr proto struct. Therefore, we must
738 * decrement the module reference count twice to ensure that it keeps
739 * zero after server's listening socket is created. Of course, we
740 * must bump the module reference count twice as well before the socket
741 * is closed.
742 */
743 module_put(qrtr_ns.sock->ops->owner);
744 module_put(qrtr_ns.sock->sk->sk_prot_creator->owner);
745
746 return 0;
747
748 err_wq:
749 destroy_workqueue(qrtr_ns.workqueue);
750 err_sock:
751 sock_release(qrtr_ns.sock);
752 return ret;
753 }
754 EXPORT_SYMBOL_GPL(qrtr_ns_init);
755
qrtr_ns_remove(void)756 void qrtr_ns_remove(void)
757 {
758 cancel_work_sync(&qrtr_ns.work);
759 destroy_workqueue(qrtr_ns.workqueue);
760
761 /* sock_release() expects the two references that were put during
762 * qrtr_ns_init(). This function is only called during module remove,
763 * so try_stop_module() has already set the refcnt to 0. Use
764 * __module_get() instead of try_module_get() to successfully take two
765 * references.
766 */
767 __module_get(qrtr_ns.sock->ops->owner);
768 __module_get(qrtr_ns.sock->sk->sk_prot_creator->owner);
769 sock_release(qrtr_ns.sock);
770 }
771 EXPORT_SYMBOL_GPL(qrtr_ns_remove);
772
773 MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
774 MODULE_DESCRIPTION("Qualcomm IPC Router Nameservice");
775 MODULE_LICENSE("Dual BSD/GPL");
776