xref: /linux/net/bluetooth/af_bluetooth.c (revision 7255fcc80d4b525cc10cfaaf7f485830d4ed2000)
1 /*
2    BlueZ - Bluetooth protocol stack for Linux
3    Copyright (C) 2000-2001 Qualcomm Incorporated
4 
5    Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com>
6 
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License version 2 as
9    published by the Free Software Foundation;
10 
11    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
12    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
13    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
14    IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
15    CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
16    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
17    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
18    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19 
20    ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
21    COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
22    SOFTWARE IS DISCLAIMED.
23 */
24 
25 /* Bluetooth address family and sockets. */
26 
27 #include <linux/module.h>
28 #include <linux/debugfs.h>
29 #include <linux/stringify.h>
30 #include <linux/sched/signal.h>
31 
32 #include <asm/ioctls.h>
33 
34 #include <net/bluetooth/bluetooth.h>
35 #include <linux/proc_fs.h>
36 
37 #include "leds.h"
38 #include "selftest.h"
39 
40 /* Bluetooth sockets */
41 #define BT_MAX_PROTO	(BTPROTO_LAST + 1)
42 static const struct net_proto_family *bt_proto[BT_MAX_PROTO];
43 static DEFINE_RWLOCK(bt_proto_lock);
44 
45 static struct lock_class_key bt_lock_key[BT_MAX_PROTO];
46 static const char *const bt_key_strings[BT_MAX_PROTO] = {
47 	"sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP",
48 	"sk_lock-AF_BLUETOOTH-BTPROTO_HCI",
49 	"sk_lock-AF_BLUETOOTH-BTPROTO_SCO",
50 	"sk_lock-AF_BLUETOOTH-BTPROTO_RFCOMM",
51 	"sk_lock-AF_BLUETOOTH-BTPROTO_BNEP",
52 	"sk_lock-AF_BLUETOOTH-BTPROTO_CMTP",
53 	"sk_lock-AF_BLUETOOTH-BTPROTO_HIDP",
54 	"sk_lock-AF_BLUETOOTH-BTPROTO_AVDTP",
55 	"sk_lock-AF_BLUETOOTH-BTPROTO_ISO",
56 };
57 
58 static struct lock_class_key bt_slock_key[BT_MAX_PROTO];
59 static const char *const bt_slock_key_strings[BT_MAX_PROTO] = {
60 	"slock-AF_BLUETOOTH-BTPROTO_L2CAP",
61 	"slock-AF_BLUETOOTH-BTPROTO_HCI",
62 	"slock-AF_BLUETOOTH-BTPROTO_SCO",
63 	"slock-AF_BLUETOOTH-BTPROTO_RFCOMM",
64 	"slock-AF_BLUETOOTH-BTPROTO_BNEP",
65 	"slock-AF_BLUETOOTH-BTPROTO_CMTP",
66 	"slock-AF_BLUETOOTH-BTPROTO_HIDP",
67 	"slock-AF_BLUETOOTH-BTPROTO_AVDTP",
68 	"slock-AF_BLUETOOTH-BTPROTO_ISO",
69 };
70 
71 void bt_sock_reclassify_lock(struct sock *sk, int proto)
72 {
73 	BUG_ON(!sk);
74 	BUG_ON(!sock_allow_reclassification(sk));
75 
76 	sock_lock_init_class_and_name(sk,
77 				      bt_slock_key_strings[proto], &bt_slock_key[proto],
78 				      bt_key_strings[proto], &bt_lock_key[proto]);
79 }
80 EXPORT_SYMBOL(bt_sock_reclassify_lock);
81 
82 int bt_sock_register(int proto, const struct net_proto_family *ops)
83 {
84 	int err = 0;
85 
86 	if (proto < 0 || proto >= BT_MAX_PROTO)
87 		return -EINVAL;
88 
89 	write_lock(&bt_proto_lock);
90 
91 	if (bt_proto[proto])
92 		err = -EEXIST;
93 	else
94 		bt_proto[proto] = ops;
95 
96 	write_unlock(&bt_proto_lock);
97 
98 	return err;
99 }
100 EXPORT_SYMBOL(bt_sock_register);
101 
102 void bt_sock_unregister(int proto)
103 {
104 	if (proto < 0 || proto >= BT_MAX_PROTO)
105 		return;
106 
107 	write_lock(&bt_proto_lock);
108 	bt_proto[proto] = NULL;
109 	write_unlock(&bt_proto_lock);
110 }
111 EXPORT_SYMBOL(bt_sock_unregister);
112 
113 static int bt_sock_create(struct net *net, struct socket *sock, int proto,
114 			  int kern)
115 {
116 	int err;
117 
118 	if (net != &init_net)
119 		return -EAFNOSUPPORT;
120 
121 	if (proto < 0 || proto >= BT_MAX_PROTO)
122 		return -EINVAL;
123 
124 	if (!bt_proto[proto])
125 		request_module("bt-proto-%d", proto);
126 
127 	err = -EPROTONOSUPPORT;
128 
129 	read_lock(&bt_proto_lock);
130 
131 	if (bt_proto[proto] && try_module_get(bt_proto[proto]->owner)) {
132 		err = bt_proto[proto]->create(net, sock, proto, kern);
133 		if (!err)
134 			bt_sock_reclassify_lock(sock->sk, proto);
135 		module_put(bt_proto[proto]->owner);
136 	}
137 
138 	read_unlock(&bt_proto_lock);
139 
140 	return err;
141 }
142 
143 struct sock *bt_sock_alloc(struct net *net, struct socket *sock,
144 			   struct proto *prot, int proto, gfp_t prio, int kern)
145 {
146 	struct sock *sk;
147 
148 	sk = sk_alloc(net, PF_BLUETOOTH, prio, prot, kern);
149 	if (!sk)
150 		return NULL;
151 
152 	sock_init_data(sock, sk);
153 	INIT_LIST_HEAD(&bt_sk(sk)->accept_q);
154 
155 	sock_reset_flag(sk, SOCK_ZAPPED);
156 
157 	sk->sk_protocol = proto;
158 	sk->sk_state    = BT_OPEN;
159 
160 	/* Init peer information so it can be properly monitored */
161 	if (!kern) {
162 		spin_lock(&sk->sk_peer_lock);
163 		sk->sk_peer_pid  = get_pid(task_tgid(current));
164 		sk->sk_peer_cred = get_current_cred();
165 		spin_unlock(&sk->sk_peer_lock);
166 	}
167 
168 	return sk;
169 }
170 EXPORT_SYMBOL(bt_sock_alloc);
171 
172 void bt_sock_link(struct bt_sock_list *l, struct sock *sk)
173 {
174 	write_lock(&l->lock);
175 	sk_add_node(sk, &l->head);
176 	write_unlock(&l->lock);
177 }
178 EXPORT_SYMBOL(bt_sock_link);
179 
180 void bt_sock_unlink(struct bt_sock_list *l, struct sock *sk)
181 {
182 	write_lock(&l->lock);
183 	sk_del_node_init(sk);
184 	write_unlock(&l->lock);
185 }
186 EXPORT_SYMBOL(bt_sock_unlink);
187 
188 void bt_accept_enqueue(struct sock *parent, struct sock *sk, bool bh)
189 {
190 	const struct cred *old_cred;
191 	struct pid *old_pid;
192 
193 	BT_DBG("parent %p, sk %p", parent, sk);
194 
195 	sock_hold(sk);
196 
197 	if (bh)
198 		bh_lock_sock_nested(sk);
199 	else
200 		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
201 
202 	list_add_tail(&bt_sk(sk)->accept_q, &bt_sk(parent)->accept_q);
203 	bt_sk(sk)->parent = parent;
204 
205 	/* Copy credentials from parent since for incoming connections the
206 	 * socket is allocated by the kernel.
207 	 */
208 	spin_lock(&sk->sk_peer_lock);
209 	old_pid = sk->sk_peer_pid;
210 	old_cred = sk->sk_peer_cred;
211 	sk->sk_peer_pid = get_pid(parent->sk_peer_pid);
212 	sk->sk_peer_cred = get_cred(parent->sk_peer_cred);
213 	spin_unlock(&sk->sk_peer_lock);
214 
215 	put_pid(old_pid);
216 	put_cred(old_cred);
217 
218 	if (bh)
219 		bh_unlock_sock(sk);
220 	else
221 		release_sock(sk);
222 
223 	sk_acceptq_added(parent);
224 }
225 EXPORT_SYMBOL(bt_accept_enqueue);
226 
227 /* Calling function must hold the sk lock.
228  * bt_sk(sk)->parent must be non-NULL meaning sk is in the parent list.
229  */
230 void bt_accept_unlink(struct sock *sk)
231 {
232 	BT_DBG("sk %p state %d", sk, sk->sk_state);
233 
234 	list_del_init(&bt_sk(sk)->accept_q);
235 	sk_acceptq_removed(bt_sk(sk)->parent);
236 	bt_sk(sk)->parent = NULL;
237 	sock_put(sk);
238 }
239 EXPORT_SYMBOL(bt_accept_unlink);
240 
241 struct sock *bt_accept_dequeue(struct sock *parent, struct socket *newsock)
242 {
243 	struct bt_sock *s, *n;
244 	struct sock *sk;
245 
246 	BT_DBG("parent %p", parent);
247 
248 restart:
249 	list_for_each_entry_safe(s, n, &bt_sk(parent)->accept_q, accept_q) {
250 		sk = (struct sock *)s;
251 
252 		/* Prevent early freeing of sk due to unlink and sock_kill */
253 		sock_hold(sk);
254 		lock_sock(sk);
255 
256 		/* Check sk has not already been unlinked via
257 		 * bt_accept_unlink() due to serialisation caused by sk locking
258 		 */
259 		if (!bt_sk(sk)->parent) {
260 			BT_DBG("sk %p, already unlinked", sk);
261 			release_sock(sk);
262 			sock_put(sk);
263 
264 			/* Restart the loop as sk is no longer in the list
265 			 * and also avoid a potential infinite loop because
266 			 * list_for_each_entry_safe() is not thread safe.
267 			 */
268 			goto restart;
269 		}
270 
271 		/* sk is safely in the parent list so reduce reference count */
272 		sock_put(sk);
273 
274 		/* FIXME: Is this check still needed */
275 		if (sk->sk_state == BT_CLOSED) {
276 			bt_accept_unlink(sk);
277 			release_sock(sk);
278 			continue;
279 		}
280 
281 		if (sk->sk_state == BT_CONNECTED || !newsock ||
282 		    test_bit(BT_SK_DEFER_SETUP, &bt_sk(parent)->flags)) {
283 			bt_accept_unlink(sk);
284 			if (newsock)
285 				sock_graft(sk, newsock);
286 
287 			release_sock(sk);
288 			return sk;
289 		}
290 
291 		release_sock(sk);
292 	}
293 
294 	return NULL;
295 }
296 EXPORT_SYMBOL(bt_accept_dequeue);
297 
298 int bt_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
299 		    int flags)
300 {
301 	struct sock *sk = sock->sk;
302 	struct sk_buff *skb;
303 	size_t copied;
304 	size_t skblen;
305 	int err;
306 
307 	BT_DBG("sock %p sk %p len %zu", sock, sk, len);
308 
309 	if (flags & MSG_OOB)
310 		return -EOPNOTSUPP;
311 
312 	skb = skb_recv_datagram(sk, flags, &err);
313 	if (!skb) {
314 		if (sk->sk_shutdown & RCV_SHUTDOWN)
315 			err = 0;
316 
317 		return err;
318 	}
319 
320 	skblen = skb->len;
321 	copied = skb->len;
322 	if (len < copied) {
323 		msg->msg_flags |= MSG_TRUNC;
324 		copied = len;
325 	}
326 
327 	skb_reset_transport_header(skb);
328 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
329 	if (err == 0) {
330 		sock_recv_cmsgs(msg, sk, skb);
331 
332 		if (msg->msg_name && bt_sk(sk)->skb_msg_name)
333 			bt_sk(sk)->skb_msg_name(skb, msg->msg_name,
334 						&msg->msg_namelen);
335 
336 		if (test_bit(BT_SK_PKT_STATUS, &bt_sk(sk)->flags)) {
337 			u8 pkt_status = hci_skb_pkt_status(skb);
338 
339 			put_cmsg(msg, SOL_BLUETOOTH, BT_SCM_PKT_STATUS,
340 				 sizeof(pkt_status), &pkt_status);
341 		}
342 	}
343 
344 	skb_free_datagram(sk, skb);
345 
346 	if (flags & MSG_TRUNC)
347 		copied = skblen;
348 
349 	return err ? : copied;
350 }
351 EXPORT_SYMBOL(bt_sock_recvmsg);
352 
353 static long bt_sock_data_wait(struct sock *sk, long timeo)
354 {
355 	DECLARE_WAITQUEUE(wait, current);
356 
357 	add_wait_queue(sk_sleep(sk), &wait);
358 	for (;;) {
359 		set_current_state(TASK_INTERRUPTIBLE);
360 
361 		if (!skb_queue_empty(&sk->sk_receive_queue))
362 			break;
363 
364 		if (sk->sk_err || (sk->sk_shutdown & RCV_SHUTDOWN))
365 			break;
366 
367 		if (signal_pending(current) || !timeo)
368 			break;
369 
370 		sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
371 		release_sock(sk);
372 		timeo = schedule_timeout(timeo);
373 		lock_sock(sk);
374 		sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
375 	}
376 
377 	__set_current_state(TASK_RUNNING);
378 	remove_wait_queue(sk_sleep(sk), &wait);
379 	return timeo;
380 }
381 
382 int bt_sock_stream_recvmsg(struct socket *sock, struct msghdr *msg,
383 			   size_t size, int flags)
384 {
385 	struct sock *sk = sock->sk;
386 	int err = 0;
387 	size_t target, copied = 0;
388 	long timeo;
389 
390 	if (flags & MSG_OOB)
391 		return -EOPNOTSUPP;
392 
393 	BT_DBG("sk %p size %zu", sk, size);
394 
395 	lock_sock(sk);
396 
397 	target = sock_rcvlowat(sk, flags & MSG_WAITALL, size);
398 	timeo  = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
399 
400 	do {
401 		struct sk_buff *skb;
402 		int chunk;
403 
404 		skb = skb_dequeue(&sk->sk_receive_queue);
405 		if (!skb) {
406 			if (copied >= target)
407 				break;
408 
409 			err = sock_error(sk);
410 			if (err)
411 				break;
412 			if (sk->sk_shutdown & RCV_SHUTDOWN)
413 				break;
414 
415 			err = -EAGAIN;
416 			if (!timeo)
417 				break;
418 
419 			timeo = bt_sock_data_wait(sk, timeo);
420 
421 			if (signal_pending(current)) {
422 				err = sock_intr_errno(timeo);
423 				goto out;
424 			}
425 			continue;
426 		}
427 
428 		chunk = min_t(unsigned int, skb->len, size);
429 		if (skb_copy_datagram_msg(skb, 0, msg, chunk)) {
430 			skb_queue_head(&sk->sk_receive_queue, skb);
431 			if (!copied)
432 				copied = -EFAULT;
433 			break;
434 		}
435 		copied += chunk;
436 		size   -= chunk;
437 
438 		sock_recv_cmsgs(msg, sk, skb);
439 
440 		if (!(flags & MSG_PEEK)) {
441 			int skb_len = skb_headlen(skb);
442 
443 			if (chunk <= skb_len) {
444 				__skb_pull(skb, chunk);
445 			} else {
446 				struct sk_buff *frag;
447 
448 				__skb_pull(skb, skb_len);
449 				chunk -= skb_len;
450 
451 				skb_walk_frags(skb, frag) {
452 					if (chunk <= frag->len) {
453 						/* Pulling partial data */
454 						skb->len -= chunk;
455 						skb->data_len -= chunk;
456 						__skb_pull(frag, chunk);
457 						break;
458 					} else if (frag->len) {
459 						/* Pulling all frag data */
460 						chunk -= frag->len;
461 						skb->len -= frag->len;
462 						skb->data_len -= frag->len;
463 						__skb_pull(frag, frag->len);
464 					}
465 				}
466 			}
467 
468 			if (skb->len) {
469 				skb_queue_head(&sk->sk_receive_queue, skb);
470 				break;
471 			}
472 			kfree_skb(skb);
473 
474 		} else {
475 			/* put message back and return */
476 			skb_queue_head(&sk->sk_receive_queue, skb);
477 			break;
478 		}
479 	} while (size);
480 
481 out:
482 	release_sock(sk);
483 	return copied ? : err;
484 }
485 EXPORT_SYMBOL(bt_sock_stream_recvmsg);
486 
487 static inline __poll_t bt_accept_poll(struct sock *parent)
488 {
489 	struct bt_sock *s, *n;
490 	struct sock *sk;
491 
492 	list_for_each_entry_safe(s, n, &bt_sk(parent)->accept_q, accept_q) {
493 		sk = (struct sock *)s;
494 		if (sk->sk_state == BT_CONNECTED ||
495 		    (test_bit(BT_SK_DEFER_SETUP, &bt_sk(parent)->flags) &&
496 		     sk->sk_state == BT_CONNECT2))
497 			return EPOLLIN | EPOLLRDNORM;
498 	}
499 
500 	return 0;
501 }
502 
503 __poll_t bt_sock_poll(struct file *file, struct socket *sock,
504 		      poll_table *wait)
505 {
506 	struct sock *sk = sock->sk;
507 	__poll_t mask = 0;
508 
509 	poll_wait(file, sk_sleep(sk), wait);
510 
511 	if (sk->sk_state == BT_LISTEN)
512 		return bt_accept_poll(sk);
513 
514 	if (sk->sk_err || !skb_queue_empty_lockless(&sk->sk_error_queue))
515 		mask |= EPOLLERR |
516 			(sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? EPOLLPRI : 0);
517 
518 	if (sk->sk_shutdown & RCV_SHUTDOWN)
519 		mask |= EPOLLRDHUP | EPOLLIN | EPOLLRDNORM;
520 
521 	if (sk->sk_shutdown == SHUTDOWN_MASK)
522 		mask |= EPOLLHUP;
523 
524 	if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
525 		mask |= EPOLLIN | EPOLLRDNORM;
526 
527 	if (sk->sk_state == BT_CLOSED)
528 		mask |= EPOLLHUP;
529 
530 	if (sk->sk_state == BT_CONNECT ||
531 	    sk->sk_state == BT_CONNECT2 ||
532 	    sk->sk_state == BT_CONFIG)
533 		return mask;
534 
535 	if (!test_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags) && sock_writeable(sk))
536 		mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
537 	else
538 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
539 
540 	return mask;
541 }
542 EXPORT_SYMBOL(bt_sock_poll);
543 
544 int bt_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
545 {
546 	struct sock *sk = sock->sk;
547 	struct sk_buff *skb;
548 	long amount;
549 	int err;
550 
551 	BT_DBG("sk %p cmd %x arg %lx", sk, cmd, arg);
552 
553 	switch (cmd) {
554 	case TIOCOUTQ:
555 		if (sk->sk_state == BT_LISTEN)
556 			return -EINVAL;
557 
558 		amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
559 		if (amount < 0)
560 			amount = 0;
561 		err = put_user(amount, (int __user *)arg);
562 		break;
563 
564 	case TIOCINQ:
565 		if (sk->sk_state == BT_LISTEN)
566 			return -EINVAL;
567 
568 		spin_lock(&sk->sk_receive_queue.lock);
569 		skb = skb_peek(&sk->sk_receive_queue);
570 		amount = skb ? skb->len : 0;
571 		spin_unlock(&sk->sk_receive_queue.lock);
572 
573 		err = put_user(amount, (int __user *)arg);
574 		break;
575 
576 	default:
577 		err = -ENOIOCTLCMD;
578 		break;
579 	}
580 
581 	return err;
582 }
583 EXPORT_SYMBOL(bt_sock_ioctl);
584 
585 /* This function expects the sk lock to be held when called */
586 int bt_sock_wait_state(struct sock *sk, int state, unsigned long timeo)
587 {
588 	DECLARE_WAITQUEUE(wait, current);
589 	int err = 0;
590 
591 	BT_DBG("sk %p", sk);
592 
593 	add_wait_queue(sk_sleep(sk), &wait);
594 	set_current_state(TASK_INTERRUPTIBLE);
595 	while (sk->sk_state != state) {
596 		if (!timeo) {
597 			err = -EINPROGRESS;
598 			break;
599 		}
600 
601 		if (signal_pending(current)) {
602 			err = sock_intr_errno(timeo);
603 			break;
604 		}
605 
606 		release_sock(sk);
607 		timeo = schedule_timeout(timeo);
608 		lock_sock(sk);
609 		set_current_state(TASK_INTERRUPTIBLE);
610 
611 		err = sock_error(sk);
612 		if (err)
613 			break;
614 	}
615 	__set_current_state(TASK_RUNNING);
616 	remove_wait_queue(sk_sleep(sk), &wait);
617 	return err;
618 }
619 EXPORT_SYMBOL(bt_sock_wait_state);
620 
621 /* This function expects the sk lock to be held when called */
622 int bt_sock_wait_ready(struct sock *sk, unsigned int msg_flags)
623 {
624 	DECLARE_WAITQUEUE(wait, current);
625 	unsigned long timeo;
626 	int err = 0;
627 
628 	BT_DBG("sk %p", sk);
629 
630 	timeo = sock_sndtimeo(sk, !!(msg_flags & MSG_DONTWAIT));
631 
632 	add_wait_queue(sk_sleep(sk), &wait);
633 	set_current_state(TASK_INTERRUPTIBLE);
634 	while (test_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags)) {
635 		if (!timeo) {
636 			err = -EAGAIN;
637 			break;
638 		}
639 
640 		if (signal_pending(current)) {
641 			err = sock_intr_errno(timeo);
642 			break;
643 		}
644 
645 		release_sock(sk);
646 		timeo = schedule_timeout(timeo);
647 		lock_sock(sk);
648 		set_current_state(TASK_INTERRUPTIBLE);
649 
650 		err = sock_error(sk);
651 		if (err)
652 			break;
653 	}
654 	__set_current_state(TASK_RUNNING);
655 	remove_wait_queue(sk_sleep(sk), &wait);
656 
657 	return err;
658 }
659 EXPORT_SYMBOL(bt_sock_wait_ready);
660 
661 #ifdef CONFIG_PROC_FS
662 static void *bt_seq_start(struct seq_file *seq, loff_t *pos)
663 	__acquires(seq->private->l->lock)
664 {
665 	struct bt_sock_list *l = pde_data(file_inode(seq->file));
666 
667 	read_lock(&l->lock);
668 	return seq_hlist_start_head(&l->head, *pos);
669 }
670 
671 static void *bt_seq_next(struct seq_file *seq, void *v, loff_t *pos)
672 {
673 	struct bt_sock_list *l = pde_data(file_inode(seq->file));
674 
675 	return seq_hlist_next(v, &l->head, pos);
676 }
677 
678 static void bt_seq_stop(struct seq_file *seq, void *v)
679 	__releases(seq->private->l->lock)
680 {
681 	struct bt_sock_list *l = pde_data(file_inode(seq->file));
682 
683 	read_unlock(&l->lock);
684 }
685 
686 static int bt_seq_show(struct seq_file *seq, void *v)
687 {
688 	struct bt_sock_list *l = pde_data(file_inode(seq->file));
689 
690 	if (v == SEQ_START_TOKEN) {
691 		seq_puts(seq, "sk               RefCnt Rmem   Wmem   User   Inode  Parent");
692 
693 		if (l->custom_seq_show) {
694 			seq_putc(seq, ' ');
695 			l->custom_seq_show(seq, v);
696 		}
697 
698 		seq_putc(seq, '\n');
699 	} else {
700 		struct sock *sk = sk_entry(v);
701 		struct bt_sock *bt = bt_sk(sk);
702 
703 		seq_printf(seq,
704 			   "%pK %-6d %-6u %-6u %-6u %-6lu %-6lu",
705 			   sk,
706 			   refcount_read(&sk->sk_refcnt),
707 			   sk_rmem_alloc_get(sk),
708 			   sk_wmem_alloc_get(sk),
709 			   from_kuid(seq_user_ns(seq), sock_i_uid(sk)),
710 			   sock_i_ino(sk),
711 			   bt->parent ? sock_i_ino(bt->parent) : 0LU);
712 
713 		if (l->custom_seq_show) {
714 			seq_putc(seq, ' ');
715 			l->custom_seq_show(seq, v);
716 		}
717 
718 		seq_putc(seq, '\n');
719 	}
720 	return 0;
721 }
722 
723 static const struct seq_operations bt_seq_ops = {
724 	.start = bt_seq_start,
725 	.next  = bt_seq_next,
726 	.stop  = bt_seq_stop,
727 	.show  = bt_seq_show,
728 };
729 
730 int bt_procfs_init(struct net *net, const char *name,
731 		   struct bt_sock_list *sk_list,
732 		   int (*seq_show)(struct seq_file *, void *))
733 {
734 	sk_list->custom_seq_show = seq_show;
735 
736 	if (!proc_create_seq_data(name, 0, net->proc_net, &bt_seq_ops, sk_list))
737 		return -ENOMEM;
738 	return 0;
739 }
740 
741 void bt_procfs_cleanup(struct net *net, const char *name)
742 {
743 	remove_proc_entry(name, net->proc_net);
744 }
745 #else
746 int bt_procfs_init(struct net *net, const char *name,
747 		   struct bt_sock_list *sk_list,
748 		   int (*seq_show)(struct seq_file *, void *))
749 {
750 	return 0;
751 }
752 
753 void bt_procfs_cleanup(struct net *net, const char *name)
754 {
755 }
756 #endif
757 EXPORT_SYMBOL(bt_procfs_init);
758 EXPORT_SYMBOL(bt_procfs_cleanup);
759 
760 static const struct net_proto_family bt_sock_family_ops = {
761 	.owner	= THIS_MODULE,
762 	.family	= PF_BLUETOOTH,
763 	.create	= bt_sock_create,
764 };
765 
766 struct dentry *bt_debugfs;
767 EXPORT_SYMBOL_GPL(bt_debugfs);
768 
769 #define VERSION __stringify(BT_SUBSYS_VERSION) "." \
770 		__stringify(BT_SUBSYS_REVISION)
771 
772 static int __init bt_init(void)
773 {
774 	int err;
775 
776 	sock_skb_cb_check_size(sizeof(struct bt_skb_cb));
777 
778 	BT_INFO("Core ver %s", VERSION);
779 
780 	err = bt_selftest();
781 	if (err < 0)
782 		return err;
783 
784 	bt_debugfs = debugfs_create_dir("bluetooth", NULL);
785 
786 	bt_leds_init();
787 
788 	err = bt_sysfs_init();
789 	if (err < 0)
790 		goto cleanup_led;
791 
792 	err = sock_register(&bt_sock_family_ops);
793 	if (err)
794 		goto cleanup_sysfs;
795 
796 	BT_INFO("HCI device and connection manager initialized");
797 
798 	err = hci_sock_init();
799 	if (err)
800 		goto unregister_socket;
801 
802 	err = l2cap_init();
803 	if (err)
804 		goto cleanup_socket;
805 
806 	err = sco_init();
807 	if (err)
808 		goto cleanup_cap;
809 
810 	err = mgmt_init();
811 	if (err)
812 		goto cleanup_sco;
813 
814 	return 0;
815 
816 cleanup_sco:
817 	sco_exit();
818 cleanup_cap:
819 	l2cap_exit();
820 cleanup_socket:
821 	hci_sock_cleanup();
822 unregister_socket:
823 	sock_unregister(PF_BLUETOOTH);
824 cleanup_sysfs:
825 	bt_sysfs_cleanup();
826 cleanup_led:
827 	bt_leds_cleanup();
828 	return err;
829 }
830 
831 static void __exit bt_exit(void)
832 {
833 	mgmt_exit();
834 
835 	sco_exit();
836 
837 	l2cap_exit();
838 
839 	hci_sock_cleanup();
840 
841 	sock_unregister(PF_BLUETOOTH);
842 
843 	bt_sysfs_cleanup();
844 
845 	bt_leds_cleanup();
846 
847 	debugfs_remove_recursive(bt_debugfs);
848 }
849 
850 subsys_initcall(bt_init);
851 module_exit(bt_exit);
852 
853 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
854 MODULE_DESCRIPTION("Bluetooth Core ver " VERSION);
855 MODULE_VERSION(VERSION);
856 MODULE_LICENSE("GPL");
857 MODULE_ALIAS_NETPROTO(PF_BLUETOOTH);
858