bluetooth : __rfcomm_dlc_close lock fix
[sfrench/cifs-2.6.git] / net / bluetooth / rfcomm / tty.c
1 /*
2    RFCOMM implementation for Linux Bluetooth stack (BlueZ).
3    Copyright (C) 2002 Maxim Krasnyansky <maxk@qualcomm.com>
4    Copyright (C) 2002 Marcel Holtmann <marcel@holtmann.org>
5
6    This program is free software; you can redistribute it and/or modify
7    it under the terms of the GNU General Public License version 2 as
8    published by the Free Software Foundation;
9
10    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
11    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
12    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
13    IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
14    CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
15    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18
19    ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
20    COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
21    SOFTWARE IS DISCLAIMED.
22 */
23
24 /*
25  * RFCOMM TTY.
26  *
27  * $Id: tty.c,v 1.24 2002/10/03 01:54:38 holtmann Exp $
28  */
29
30 #include <linux/module.h>
31
32 #include <linux/tty.h>
33 #include <linux/tty_driver.h>
34 #include <linux/tty_flip.h>
35
36 #include <linux/capability.h>
37 #include <linux/slab.h>
38 #include <linux/skbuff.h>
39
40 #include <net/bluetooth/bluetooth.h>
41 #include <net/bluetooth/hci_core.h>
42 #include <net/bluetooth/rfcomm.h>
43
44 #ifndef CONFIG_BT_RFCOMM_DEBUG
45 #undef  BT_DBG
46 #define BT_DBG(D...)
47 #endif
48
49 #define RFCOMM_TTY_MAGIC 0x6d02         /* magic number for rfcomm struct */
50 #define RFCOMM_TTY_PORTS RFCOMM_MAX_DEV /* whole lotta rfcomm devices */
51 #define RFCOMM_TTY_MAJOR 216            /* device node major id of the usb/bluetooth.c driver */
52 #define RFCOMM_TTY_MINOR 0
53
54 static struct tty_driver *rfcomm_tty_driver;
55
56 struct rfcomm_dev {
57         struct list_head        list;
58         atomic_t                refcnt;
59
60         char                    name[12];
61         int                     id;
62         unsigned long           flags;
63         int                     opened;
64         int                     err;
65
66         bdaddr_t                src;
67         bdaddr_t                dst;
68         u8                      channel;
69
70         uint                    modem_status;
71
72         struct rfcomm_dlc       *dlc;
73         struct tty_struct       *tty;
74         wait_queue_head_t       wait;
75         struct tasklet_struct   wakeup_task;
76
77         struct device           *tty_dev;
78
79         atomic_t                wmem_alloc;
80 };
81
82 static LIST_HEAD(rfcomm_dev_list);
83 static DEFINE_RWLOCK(rfcomm_dev_lock);
84
85 static void rfcomm_dev_data_ready(struct rfcomm_dlc *dlc, struct sk_buff *skb);
86 static void rfcomm_dev_state_change(struct rfcomm_dlc *dlc, int err);
87 static void rfcomm_dev_modem_status(struct rfcomm_dlc *dlc, u8 v24_sig);
88
89 static void rfcomm_tty_wakeup(unsigned long arg);
90
91 /* ---- Device functions ---- */
92 static void rfcomm_dev_destruct(struct rfcomm_dev *dev)
93 {
94         struct rfcomm_dlc *dlc = dev->dlc;
95
96         BT_DBG("dev %p dlc %p", dev, dlc);
97
98         /* Refcount should only hit zero when called from rfcomm_dev_del()
99            which will have taken us off the list. Everything else are
100            refcounting bugs. */
101         BUG_ON(!list_empty(&dev->list));
102
103         rfcomm_dlc_lock(dlc);
104         /* Detach DLC if it's owned by this dev */
105         if (dlc->owner == dev)
106                 dlc->owner = NULL;
107         rfcomm_dlc_unlock(dlc);
108
109         rfcomm_dlc_put(dlc);
110
111         tty_unregister_device(rfcomm_tty_driver, dev->id);
112
113         kfree(dev);
114
115         /* It's safe to call module_put() here because socket still
116            holds reference to this module. */
117         module_put(THIS_MODULE);
118 }
119
120 static inline void rfcomm_dev_hold(struct rfcomm_dev *dev)
121 {
122         atomic_inc(&dev->refcnt);
123 }
124
125 static inline void rfcomm_dev_put(struct rfcomm_dev *dev)
126 {
127         /* The reason this isn't actually a race, as you no
128            doubt have a little voice screaming at you in your
129            head, is that the refcount should never actually
130            reach zero unless the device has already been taken
131            off the list, in rfcomm_dev_del(). And if that's not
132            true, we'll hit the BUG() in rfcomm_dev_destruct()
133            anyway. */
134         if (atomic_dec_and_test(&dev->refcnt))
135                 rfcomm_dev_destruct(dev);
136 }
137
138 static struct rfcomm_dev *__rfcomm_dev_get(int id)
139 {
140         struct rfcomm_dev *dev;
141         struct list_head  *p;
142
143         list_for_each(p, &rfcomm_dev_list) {
144                 dev = list_entry(p, struct rfcomm_dev, list);
145                 if (dev->id == id)
146                         return dev;
147         }
148
149         return NULL;
150 }
151
152 static inline struct rfcomm_dev *rfcomm_dev_get(int id)
153 {
154         struct rfcomm_dev *dev;
155
156         read_lock(&rfcomm_dev_lock);
157
158         dev = __rfcomm_dev_get(id);
159
160         if (dev) {
161                 if (test_bit(RFCOMM_TTY_RELEASED, &dev->flags))
162                         dev = NULL;
163                 else
164                         rfcomm_dev_hold(dev);
165         }
166
167         read_unlock(&rfcomm_dev_lock);
168
169         return dev;
170 }
171
172 static struct device *rfcomm_get_device(struct rfcomm_dev *dev)
173 {
174         struct hci_dev *hdev;
175         struct hci_conn *conn;
176
177         hdev = hci_get_route(&dev->dst, &dev->src);
178         if (!hdev)
179                 return NULL;
180
181         conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &dev->dst);
182
183         hci_dev_put(hdev);
184
185         return conn ? &conn->dev : NULL;
186 }
187
188 static ssize_t show_address(struct device *tty_dev, struct device_attribute *attr, char *buf)
189 {
190         struct rfcomm_dev *dev = dev_get_drvdata(tty_dev);
191         bdaddr_t bdaddr;
192         baswap(&bdaddr, &dev->dst);
193         return sprintf(buf, "%s\n", batostr(&bdaddr));
194 }
195
196 static ssize_t show_channel(struct device *tty_dev, struct device_attribute *attr, char *buf)
197 {
198         struct rfcomm_dev *dev = dev_get_drvdata(tty_dev);
199         return sprintf(buf, "%d\n", dev->channel);
200 }
201
202 static DEVICE_ATTR(address, S_IRUGO, show_address, NULL);
203 static DEVICE_ATTR(channel, S_IRUGO, show_channel, NULL);
204
205 static int rfcomm_dev_add(struct rfcomm_dev_req *req, struct rfcomm_dlc *dlc)
206 {
207         struct rfcomm_dev *dev;
208         struct list_head *head = &rfcomm_dev_list, *p;
209         int err = 0;
210
211         BT_DBG("id %d channel %d", req->dev_id, req->channel);
212
213         dev = kzalloc(sizeof(struct rfcomm_dev), GFP_KERNEL);
214         if (!dev)
215                 return -ENOMEM;
216
217         write_lock_bh(&rfcomm_dev_lock);
218
219         if (req->dev_id < 0) {
220                 dev->id = 0;
221
222                 list_for_each(p, &rfcomm_dev_list) {
223                         if (list_entry(p, struct rfcomm_dev, list)->id != dev->id)
224                                 break;
225
226                         dev->id++;
227                         head = p;
228                 }
229         } else {
230                 dev->id = req->dev_id;
231
232                 list_for_each(p, &rfcomm_dev_list) {
233                         struct rfcomm_dev *entry = list_entry(p, struct rfcomm_dev, list);
234
235                         if (entry->id == dev->id) {
236                                 err = -EADDRINUSE;
237                                 goto out;
238                         }
239
240                         if (entry->id > dev->id - 1)
241                                 break;
242
243                         head = p;
244                 }
245         }
246
247         if ((dev->id < 0) || (dev->id > RFCOMM_MAX_DEV - 1)) {
248                 err = -ENFILE;
249                 goto out;
250         }
251
252         sprintf(dev->name, "rfcomm%d", dev->id);
253
254         list_add(&dev->list, head);
255         atomic_set(&dev->refcnt, 1);
256
257         bacpy(&dev->src, &req->src);
258         bacpy(&dev->dst, &req->dst);
259         dev->channel = req->channel;
260
261         dev->flags = req->flags &
262                 ((1 << RFCOMM_RELEASE_ONHUP) | (1 << RFCOMM_REUSE_DLC));
263
264         init_waitqueue_head(&dev->wait);
265         tasklet_init(&dev->wakeup_task, rfcomm_tty_wakeup, (unsigned long) dev);
266
267         rfcomm_dlc_lock(dlc);
268         dlc->data_ready   = rfcomm_dev_data_ready;
269         dlc->state_change = rfcomm_dev_state_change;
270         dlc->modem_status = rfcomm_dev_modem_status;
271
272         dlc->owner = dev;
273         dev->dlc   = dlc;
274         rfcomm_dlc_unlock(dlc);
275
276         /* It's safe to call __module_get() here because socket already
277            holds reference to this module. */
278         __module_get(THIS_MODULE);
279
280 out:
281         write_unlock_bh(&rfcomm_dev_lock);
282
283         if (err < 0) {
284                 kfree(dev);
285                 return err;
286         }
287
288         dev->tty_dev = tty_register_device(rfcomm_tty_driver, dev->id, NULL);
289
290         if (IS_ERR(dev->tty_dev)) {
291                 err = PTR_ERR(dev->tty_dev);
292                 list_del(&dev->list);
293                 kfree(dev);
294                 return err;
295         }
296
297         dev_set_drvdata(dev->tty_dev, dev);
298
299         if (device_create_file(dev->tty_dev, &dev_attr_address) < 0)
300                 BT_ERR("Failed to create address attribute");
301
302         if (device_create_file(dev->tty_dev, &dev_attr_channel) < 0)
303                 BT_ERR("Failed to create channel attribute");
304
305         return dev->id;
306 }
307
308 static void rfcomm_dev_del(struct rfcomm_dev *dev)
309 {
310         BT_DBG("dev %p", dev);
311
312         if (test_bit(RFCOMM_TTY_RELEASED, &dev->flags))
313                 BUG_ON(1);
314         else
315                 set_bit(RFCOMM_TTY_RELEASED, &dev->flags);
316
317         write_lock_bh(&rfcomm_dev_lock);
318         list_del_init(&dev->list);
319         write_unlock_bh(&rfcomm_dev_lock);
320
321         rfcomm_dev_put(dev);
322 }
323
324 /* ---- Send buffer ---- */
325 static inline unsigned int rfcomm_room(struct rfcomm_dlc *dlc)
326 {
327         /* We can't let it be zero, because we don't get a callback
328            when tx_credits becomes nonzero, hence we'd never wake up */
329         return dlc->mtu * (dlc->tx_credits?:1);
330 }
331
332 static void rfcomm_wfree(struct sk_buff *skb)
333 {
334         struct rfcomm_dev *dev = (void *) skb->sk;
335         atomic_sub(skb->truesize, &dev->wmem_alloc);
336         if (test_bit(RFCOMM_TTY_ATTACHED, &dev->flags))
337                 tasklet_schedule(&dev->wakeup_task);
338         rfcomm_dev_put(dev);
339 }
340
341 static inline void rfcomm_set_owner_w(struct sk_buff *skb, struct rfcomm_dev *dev)
342 {
343         rfcomm_dev_hold(dev);
344         atomic_add(skb->truesize, &dev->wmem_alloc);
345         skb->sk = (void *) dev;
346         skb->destructor = rfcomm_wfree;
347 }
348
349 static struct sk_buff *rfcomm_wmalloc(struct rfcomm_dev *dev, unsigned long size, gfp_t priority)
350 {
351         if (atomic_read(&dev->wmem_alloc) < rfcomm_room(dev->dlc)) {
352                 struct sk_buff *skb = alloc_skb(size, priority);
353                 if (skb) {
354                         rfcomm_set_owner_w(skb, dev);
355                         return skb;
356                 }
357         }
358         return NULL;
359 }
360
361 /* ---- Device IOCTLs ---- */
362
363 #define NOCAP_FLAGS ((1 << RFCOMM_REUSE_DLC) | (1 << RFCOMM_RELEASE_ONHUP))
364
365 static int rfcomm_create_dev(struct sock *sk, void __user *arg)
366 {
367         struct rfcomm_dev_req req;
368         struct rfcomm_dlc *dlc;
369         int id;
370
371         if (copy_from_user(&req, arg, sizeof(req)))
372                 return -EFAULT;
373
374         BT_DBG("sk %p dev_id %d flags 0x%x", sk, req.dev_id, req.flags);
375
376         if (req.flags != NOCAP_FLAGS && !capable(CAP_NET_ADMIN))
377                 return -EPERM;
378
379         if (req.flags & (1 << RFCOMM_REUSE_DLC)) {
380                 /* Socket must be connected */
381                 if (sk->sk_state != BT_CONNECTED)
382                         return -EBADFD;
383
384                 dlc = rfcomm_pi(sk)->dlc;
385                 rfcomm_dlc_hold(dlc);
386         } else {
387                 dlc = rfcomm_dlc_alloc(GFP_KERNEL);
388                 if (!dlc)
389                         return -ENOMEM;
390         }
391
392         id = rfcomm_dev_add(&req, dlc);
393         if (id < 0) {
394                 rfcomm_dlc_put(dlc);
395                 return id;
396         }
397
398         if (req.flags & (1 << RFCOMM_REUSE_DLC)) {
399                 /* DLC is now used by device.
400                  * Socket must be disconnected */
401                 sk->sk_state = BT_CLOSED;
402         }
403
404         return id;
405 }
406
407 static int rfcomm_release_dev(void __user *arg)
408 {
409         struct rfcomm_dev_req req;
410         struct rfcomm_dev *dev;
411
412         if (copy_from_user(&req, arg, sizeof(req)))
413                 return -EFAULT;
414
415         BT_DBG("dev_id %d flags 0x%x", req.dev_id, req.flags);
416
417         if (!(dev = rfcomm_dev_get(req.dev_id)))
418                 return -ENODEV;
419
420         if (dev->flags != NOCAP_FLAGS && !capable(CAP_NET_ADMIN)) {
421                 rfcomm_dev_put(dev);
422                 return -EPERM;
423         }
424
425         if (req.flags & (1 << RFCOMM_HANGUP_NOW))
426                 rfcomm_dlc_close(dev->dlc, 0);
427
428         /* Shut down TTY synchronously before freeing rfcomm_dev */
429         if (dev->tty)
430                 tty_vhangup(dev->tty);
431
432         if (!test_bit(RFCOMM_RELEASE_ONHUP, &dev->flags))
433                 rfcomm_dev_del(dev);
434         rfcomm_dev_put(dev);
435         return 0;
436 }
437
438 static int rfcomm_get_dev_list(void __user *arg)
439 {
440         struct rfcomm_dev_list_req *dl;
441         struct rfcomm_dev_info *di;
442         struct list_head *p;
443         int n = 0, size, err;
444         u16 dev_num;
445
446         BT_DBG("");
447
448         if (get_user(dev_num, (u16 __user *) arg))
449                 return -EFAULT;
450
451         if (!dev_num || dev_num > (PAGE_SIZE * 4) / sizeof(*di))
452                 return -EINVAL;
453
454         size = sizeof(*dl) + dev_num * sizeof(*di);
455
456         if (!(dl = kmalloc(size, GFP_KERNEL)))
457                 return -ENOMEM;
458
459         di = dl->dev_info;
460
461         read_lock_bh(&rfcomm_dev_lock);
462
463         list_for_each(p, &rfcomm_dev_list) {
464                 struct rfcomm_dev *dev = list_entry(p, struct rfcomm_dev, list);
465                 if (test_bit(RFCOMM_TTY_RELEASED, &dev->flags))
466                         continue;
467                 (di + n)->id      = dev->id;
468                 (di + n)->flags   = dev->flags;
469                 (di + n)->state   = dev->dlc->state;
470                 (di + n)->channel = dev->channel;
471                 bacpy(&(di + n)->src, &dev->src);
472                 bacpy(&(di + n)->dst, &dev->dst);
473                 if (++n >= dev_num)
474                         break;
475         }
476
477         read_unlock_bh(&rfcomm_dev_lock);
478
479         dl->dev_num = n;
480         size = sizeof(*dl) + n * sizeof(*di);
481
482         err = copy_to_user(arg, dl, size);
483         kfree(dl);
484
485         return err ? -EFAULT : 0;
486 }
487
488 static int rfcomm_get_dev_info(void __user *arg)
489 {
490         struct rfcomm_dev *dev;
491         struct rfcomm_dev_info di;
492         int err = 0;
493
494         BT_DBG("");
495
496         if (copy_from_user(&di, arg, sizeof(di)))
497                 return -EFAULT;
498
499         if (!(dev = rfcomm_dev_get(di.id)))
500                 return -ENODEV;
501
502         di.flags   = dev->flags;
503         di.channel = dev->channel;
504         di.state   = dev->dlc->state;
505         bacpy(&di.src, &dev->src);
506         bacpy(&di.dst, &dev->dst);
507
508         if (copy_to_user(arg, &di, sizeof(di)))
509                 err = -EFAULT;
510
511         rfcomm_dev_put(dev);
512         return err;
513 }
514
515 int rfcomm_dev_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
516 {
517         BT_DBG("cmd %d arg %p", cmd, arg);
518
519         switch (cmd) {
520         case RFCOMMCREATEDEV:
521                 return rfcomm_create_dev(sk, arg);
522
523         case RFCOMMRELEASEDEV:
524                 return rfcomm_release_dev(arg);
525
526         case RFCOMMGETDEVLIST:
527                 return rfcomm_get_dev_list(arg);
528
529         case RFCOMMGETDEVINFO:
530                 return rfcomm_get_dev_info(arg);
531         }
532
533         return -EINVAL;
534 }
535
536 /* ---- DLC callbacks ---- */
537 static void rfcomm_dev_data_ready(struct rfcomm_dlc *dlc, struct sk_buff *skb)
538 {
539         struct rfcomm_dev *dev = dlc->owner;
540         struct tty_struct *tty;
541
542         if (!dev || !(tty = dev->tty)) {
543                 kfree_skb(skb);
544                 return;
545         }
546
547         BT_DBG("dlc %p tty %p len %d", dlc, tty, skb->len);
548
549         tty_insert_flip_string(tty, skb->data, skb->len);
550         tty_flip_buffer_push(tty);
551
552         kfree_skb(skb);
553 }
554
555 static void rfcomm_dev_state_change(struct rfcomm_dlc *dlc, int err)
556 {
557         struct rfcomm_dev *dev = dlc->owner;
558         if (!dev)
559                 return;
560
561         BT_DBG("dlc %p dev %p err %d", dlc, dev, err);
562
563         dev->err = err;
564         wake_up_interruptible(&dev->wait);
565
566         if (dlc->state == BT_CLOSED) {
567                 if (!dev->tty) {
568                         if (test_bit(RFCOMM_RELEASE_ONHUP, &dev->flags)) {
569                                 if (rfcomm_dev_get(dev->id) == NULL)
570                                         return;
571
572                                 rfcomm_dev_del(dev);
573                                 rfcomm_dev_put(dev);
574                         }
575                 } else
576                         tty_hangup(dev->tty);
577         }
578 }
579
580 static void rfcomm_dev_modem_status(struct rfcomm_dlc *dlc, u8 v24_sig)
581 {
582         struct rfcomm_dev *dev = dlc->owner;
583         if (!dev)
584                 return;
585
586         BT_DBG("dlc %p dev %p v24_sig 0x%02x", dlc, dev, v24_sig);
587
588         if ((dev->modem_status & TIOCM_CD) && !(v24_sig & RFCOMM_V24_DV)) {
589                 if (dev->tty && !C_CLOCAL(dev->tty))
590                         tty_hangup(dev->tty);
591         }
592
593         dev->modem_status =
594                 ((v24_sig & RFCOMM_V24_RTC) ? (TIOCM_DSR | TIOCM_DTR) : 0) |
595                 ((v24_sig & RFCOMM_V24_RTR) ? (TIOCM_RTS | TIOCM_CTS) : 0) |
596                 ((v24_sig & RFCOMM_V24_IC)  ? TIOCM_RI : 0) |
597                 ((v24_sig & RFCOMM_V24_DV)  ? TIOCM_CD : 0);
598 }
599
600 /* ---- TTY functions ---- */
601 static void rfcomm_tty_wakeup(unsigned long arg)
602 {
603         struct rfcomm_dev *dev = (void *) arg;
604         struct tty_struct *tty = dev->tty;
605         if (!tty)
606                 return;
607
608         BT_DBG("dev %p tty %p", dev, tty);
609
610         if (test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags) && tty->ldisc.write_wakeup)
611                 (tty->ldisc.write_wakeup)(tty);
612
613         wake_up_interruptible(&tty->write_wait);
614 #ifdef SERIAL_HAVE_POLL_WAIT
615         wake_up_interruptible(&tty->poll_wait);
616 #endif
617 }
618
619 static int rfcomm_tty_open(struct tty_struct *tty, struct file *filp)
620 {
621         DECLARE_WAITQUEUE(wait, current);
622         struct rfcomm_dev *dev;
623         struct rfcomm_dlc *dlc;
624         int err, id;
625
626         id = tty->index;
627
628         BT_DBG("tty %p id %d", tty, id);
629
630         /* We don't leak this refcount. For reasons which are not entirely
631            clear, the TTY layer will call our ->close() method even if the
632            open fails. We decrease the refcount there, and decreasing it
633            here too would cause breakage. */
634         dev = rfcomm_dev_get(id);
635         if (!dev)
636                 return -ENODEV;
637
638         BT_DBG("dev %p dst %s channel %d opened %d", dev, batostr(&dev->dst), dev->channel, dev->opened);
639
640         if (dev->opened++ != 0)
641                 return 0;
642
643         dlc = dev->dlc;
644
645         /* Attach TTY and open DLC */
646
647         rfcomm_dlc_lock(dlc);
648         tty->driver_data = dev;
649         dev->tty = tty;
650         rfcomm_dlc_unlock(dlc);
651         set_bit(RFCOMM_TTY_ATTACHED, &dev->flags);
652
653         err = rfcomm_dlc_open(dlc, &dev->src, &dev->dst, dev->channel);
654         if (err < 0)
655                 return err;
656
657         /* Wait for DLC to connect */
658         add_wait_queue(&dev->wait, &wait);
659         while (1) {
660                 set_current_state(TASK_INTERRUPTIBLE);
661
662                 if (dlc->state == BT_CLOSED) {
663                         err = -dev->err;
664                         break;
665                 }
666
667                 if (dlc->state == BT_CONNECTED)
668                         break;
669
670                 if (signal_pending(current)) {
671                         err = -EINTR;
672                         break;
673                 }
674
675                 schedule();
676         }
677         set_current_state(TASK_RUNNING);
678         remove_wait_queue(&dev->wait, &wait);
679
680         if (err == 0)
681                 device_move(dev->tty_dev, rfcomm_get_device(dev));
682
683         return err;
684 }
685
686 static void rfcomm_tty_close(struct tty_struct *tty, struct file *filp)
687 {
688         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
689         if (!dev)
690                 return;
691
692         BT_DBG("tty %p dev %p dlc %p opened %d", tty, dev, dev->dlc, dev->opened);
693
694         if (--dev->opened == 0) {
695                 if (dev->tty_dev->parent)
696                         device_move(dev->tty_dev, NULL);
697
698                 /* Close DLC and dettach TTY */
699                 rfcomm_dlc_close(dev->dlc, 0);
700
701                 clear_bit(RFCOMM_TTY_ATTACHED, &dev->flags);
702                 tasklet_kill(&dev->wakeup_task);
703
704                 rfcomm_dlc_lock(dev->dlc);
705                 tty->driver_data = NULL;
706                 dev->tty = NULL;
707                 rfcomm_dlc_unlock(dev->dlc);
708         }
709
710         rfcomm_dev_put(dev);
711 }
712
713 static int rfcomm_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
714 {
715         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
716         struct rfcomm_dlc *dlc = dev->dlc;
717         struct sk_buff *skb;
718         int err = 0, sent = 0, size;
719
720         BT_DBG("tty %p count %d", tty, count);
721
722         while (count) {
723                 size = min_t(uint, count, dlc->mtu);
724
725                 skb = rfcomm_wmalloc(dev, size + RFCOMM_SKB_RESERVE, GFP_ATOMIC);
726
727                 if (!skb)
728                         break;
729
730                 skb_reserve(skb, RFCOMM_SKB_HEAD_RESERVE);
731
732                 memcpy(skb_put(skb, size), buf + sent, size);
733
734                 if ((err = rfcomm_dlc_send(dlc, skb)) < 0) {
735                         kfree_skb(skb);
736                         break;
737                 }
738
739                 sent  += size;
740                 count -= size;
741         }
742
743         return sent ? sent : err;
744 }
745
746 static int rfcomm_tty_write_room(struct tty_struct *tty)
747 {
748         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
749         int room;
750
751         BT_DBG("tty %p", tty);
752
753         if (!dev || !dev->dlc)
754                 return 0;
755
756         room = rfcomm_room(dev->dlc) - atomic_read(&dev->wmem_alloc);
757         if (room < 0)
758                 room = 0;
759
760         return room;
761 }
762
763 static int rfcomm_tty_ioctl(struct tty_struct *tty, struct file *filp, unsigned int cmd, unsigned long arg)
764 {
765         BT_DBG("tty %p cmd 0x%02x", tty, cmd);
766
767         switch (cmd) {
768         case TCGETS:
769                 BT_DBG("TCGETS is not supported");
770                 return -ENOIOCTLCMD;
771
772         case TCSETS:
773                 BT_DBG("TCSETS is not supported");
774                 return -ENOIOCTLCMD;
775
776         case TIOCMIWAIT:
777                 BT_DBG("TIOCMIWAIT");
778                 break;
779
780         case TIOCGICOUNT:
781                 BT_DBG("TIOCGICOUNT");
782                 break;
783
784         case TIOCGSERIAL:
785                 BT_ERR("TIOCGSERIAL is not supported");
786                 return -ENOIOCTLCMD;
787
788         case TIOCSSERIAL:
789                 BT_ERR("TIOCSSERIAL is not supported");
790                 return -ENOIOCTLCMD;
791
792         case TIOCSERGSTRUCT:
793                 BT_ERR("TIOCSERGSTRUCT is not supported");
794                 return -ENOIOCTLCMD;
795
796         case TIOCSERGETLSR:
797                 BT_ERR("TIOCSERGETLSR is not supported");
798                 return -ENOIOCTLCMD;
799
800         case TIOCSERCONFIG:
801                 BT_ERR("TIOCSERCONFIG is not supported");
802                 return -ENOIOCTLCMD;
803
804         default:
805                 return -ENOIOCTLCMD;    /* ioctls which we must ignore */
806
807         }
808
809         return -ENOIOCTLCMD;
810 }
811
812 static void rfcomm_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
813 {
814         struct ktermios *new = tty->termios;
815         int old_baud_rate = tty_termios_baud_rate(old);
816         int new_baud_rate = tty_termios_baud_rate(new);
817
818         u8 baud, data_bits, stop_bits, parity, x_on, x_off;
819         u16 changes = 0;
820
821         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
822
823         BT_DBG("tty %p termios %p", tty, old);
824
825         if (!dev || !dev->dlc || !dev->dlc->session)
826                 return;
827
828         /* Handle turning off CRTSCTS */
829         if ((old->c_cflag & CRTSCTS) && !(new->c_cflag & CRTSCTS))
830                 BT_DBG("Turning off CRTSCTS unsupported");
831
832         /* Parity on/off and when on, odd/even */
833         if (((old->c_cflag & PARENB) != (new->c_cflag & PARENB)) ||
834                         ((old->c_cflag & PARODD) != (new->c_cflag & PARODD)) ) {
835                 changes |= RFCOMM_RPN_PM_PARITY;
836                 BT_DBG("Parity change detected.");
837         }
838
839         /* Mark and space parity are not supported! */
840         if (new->c_cflag & PARENB) {
841                 if (new->c_cflag & PARODD) {
842                         BT_DBG("Parity is ODD");
843                         parity = RFCOMM_RPN_PARITY_ODD;
844                 } else {
845                         BT_DBG("Parity is EVEN");
846                         parity = RFCOMM_RPN_PARITY_EVEN;
847                 }
848         } else {
849                 BT_DBG("Parity is OFF");
850                 parity = RFCOMM_RPN_PARITY_NONE;
851         }
852
853         /* Setting the x_on / x_off characters */
854         if (old->c_cc[VSTOP] != new->c_cc[VSTOP]) {
855                 BT_DBG("XOFF custom");
856                 x_on = new->c_cc[VSTOP];
857                 changes |= RFCOMM_RPN_PM_XON;
858         } else {
859                 BT_DBG("XOFF default");
860                 x_on = RFCOMM_RPN_XON_CHAR;
861         }
862
863         if (old->c_cc[VSTART] != new->c_cc[VSTART]) {
864                 BT_DBG("XON custom");
865                 x_off = new->c_cc[VSTART];
866                 changes |= RFCOMM_RPN_PM_XOFF;
867         } else {
868                 BT_DBG("XON default");
869                 x_off = RFCOMM_RPN_XOFF_CHAR;
870         }
871
872         /* Handle setting of stop bits */
873         if ((old->c_cflag & CSTOPB) != (new->c_cflag & CSTOPB))
874                 changes |= RFCOMM_RPN_PM_STOP;
875
876         /* POSIX does not support 1.5 stop bits and RFCOMM does not
877          * support 2 stop bits. So a request for 2 stop bits gets
878          * translated to 1.5 stop bits */
879         if (new->c_cflag & CSTOPB) {
880                 stop_bits = RFCOMM_RPN_STOP_15;
881         } else {
882                 stop_bits = RFCOMM_RPN_STOP_1;
883         }
884
885         /* Handle number of data bits [5-8] */
886         if ((old->c_cflag & CSIZE) != (new->c_cflag & CSIZE))
887                 changes |= RFCOMM_RPN_PM_DATA;
888
889         switch (new->c_cflag & CSIZE) {
890         case CS5:
891                 data_bits = RFCOMM_RPN_DATA_5;
892                 break;
893         case CS6:
894                 data_bits = RFCOMM_RPN_DATA_6;
895                 break;
896         case CS7:
897                 data_bits = RFCOMM_RPN_DATA_7;
898                 break;
899         case CS8:
900                 data_bits = RFCOMM_RPN_DATA_8;
901                 break;
902         default:
903                 data_bits = RFCOMM_RPN_DATA_8;
904                 break;
905         }
906
907         /* Handle baudrate settings */
908         if (old_baud_rate != new_baud_rate)
909                 changes |= RFCOMM_RPN_PM_BITRATE;
910
911         switch (new_baud_rate) {
912         case 2400:
913                 baud = RFCOMM_RPN_BR_2400;
914                 break;
915         case 4800:
916                 baud = RFCOMM_RPN_BR_4800;
917                 break;
918         case 7200:
919                 baud = RFCOMM_RPN_BR_7200;
920                 break;
921         case 9600:
922                 baud = RFCOMM_RPN_BR_9600;
923                 break;
924         case 19200:
925                 baud = RFCOMM_RPN_BR_19200;
926                 break;
927         case 38400:
928                 baud = RFCOMM_RPN_BR_38400;
929                 break;
930         case 57600:
931                 baud = RFCOMM_RPN_BR_57600;
932                 break;
933         case 115200:
934                 baud = RFCOMM_RPN_BR_115200;
935                 break;
936         case 230400:
937                 baud = RFCOMM_RPN_BR_230400;
938                 break;
939         default:
940                 /* 9600 is standard accordinag to the RFCOMM specification */
941                 baud = RFCOMM_RPN_BR_9600;
942                 break;
943
944         }
945
946         if (changes)
947                 rfcomm_send_rpn(dev->dlc->session, 1, dev->dlc->dlci, baud,
948                                 data_bits, stop_bits, parity,
949                                 RFCOMM_RPN_FLOW_NONE, x_on, x_off, changes);
950
951         return;
952 }
953
954 static void rfcomm_tty_throttle(struct tty_struct *tty)
955 {
956         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
957
958         BT_DBG("tty %p dev %p", tty, dev);
959
960         rfcomm_dlc_throttle(dev->dlc);
961 }
962
963 static void rfcomm_tty_unthrottle(struct tty_struct *tty)
964 {
965         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
966
967         BT_DBG("tty %p dev %p", tty, dev);
968
969         rfcomm_dlc_unthrottle(dev->dlc);
970 }
971
972 static int rfcomm_tty_chars_in_buffer(struct tty_struct *tty)
973 {
974         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
975
976         BT_DBG("tty %p dev %p", tty, dev);
977
978         if (!dev || !dev->dlc)
979                 return 0;
980
981         if (!skb_queue_empty(&dev->dlc->tx_queue))
982                 return dev->dlc->mtu;
983
984         return 0;
985 }
986
987 static void rfcomm_tty_flush_buffer(struct tty_struct *tty)
988 {
989         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
990
991         BT_DBG("tty %p dev %p", tty, dev);
992
993         if (!dev || !dev->dlc)
994                 return;
995
996         skb_queue_purge(&dev->dlc->tx_queue);
997
998         if (test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags) && tty->ldisc.write_wakeup)
999                 tty->ldisc.write_wakeup(tty);
1000 }
1001
1002 static void rfcomm_tty_send_xchar(struct tty_struct *tty, char ch)
1003 {
1004         BT_DBG("tty %p ch %c", tty, ch);
1005 }
1006
1007 static void rfcomm_tty_wait_until_sent(struct tty_struct *tty, int timeout)
1008 {
1009         BT_DBG("tty %p timeout %d", tty, timeout);
1010 }
1011
1012 static void rfcomm_tty_hangup(struct tty_struct *tty)
1013 {
1014         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
1015
1016         BT_DBG("tty %p dev %p", tty, dev);
1017
1018         if (!dev)
1019                 return;
1020
1021         rfcomm_tty_flush_buffer(tty);
1022
1023         if (test_bit(RFCOMM_RELEASE_ONHUP, &dev->flags)) {
1024                 if (rfcomm_dev_get(dev->id) == NULL)
1025                         return;
1026                 rfcomm_dev_del(dev);
1027                 rfcomm_dev_put(dev);
1028         }
1029 }
1030
1031 static int rfcomm_tty_read_proc(char *buf, char **start, off_t offset, int len, int *eof, void *unused)
1032 {
1033         return 0;
1034 }
1035
1036 static int rfcomm_tty_tiocmget(struct tty_struct *tty, struct file *filp)
1037 {
1038         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
1039
1040         BT_DBG("tty %p dev %p", tty, dev);
1041
1042         return dev->modem_status;
1043 }
1044
1045 static int rfcomm_tty_tiocmset(struct tty_struct *tty, struct file *filp, unsigned int set, unsigned int clear)
1046 {
1047         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
1048         struct rfcomm_dlc *dlc = dev->dlc;
1049         u8 v24_sig;
1050
1051         BT_DBG("tty %p dev %p set 0x%02x clear 0x%02x", tty, dev, set, clear);
1052
1053         rfcomm_dlc_get_modem_status(dlc, &v24_sig);
1054
1055         if (set & TIOCM_DSR || set & TIOCM_DTR)
1056                 v24_sig |= RFCOMM_V24_RTC;
1057         if (set & TIOCM_RTS || set & TIOCM_CTS)
1058                 v24_sig |= RFCOMM_V24_RTR;
1059         if (set & TIOCM_RI)
1060                 v24_sig |= RFCOMM_V24_IC;
1061         if (set & TIOCM_CD)
1062                 v24_sig |= RFCOMM_V24_DV;
1063
1064         if (clear & TIOCM_DSR || clear & TIOCM_DTR)
1065                 v24_sig &= ~RFCOMM_V24_RTC;
1066         if (clear & TIOCM_RTS || clear & TIOCM_CTS)
1067                 v24_sig &= ~RFCOMM_V24_RTR;
1068         if (clear & TIOCM_RI)
1069                 v24_sig &= ~RFCOMM_V24_IC;
1070         if (clear & TIOCM_CD)
1071                 v24_sig &= ~RFCOMM_V24_DV;
1072
1073         rfcomm_dlc_set_modem_status(dlc, v24_sig);
1074
1075         return 0;
1076 }
1077
1078 /* ---- TTY structure ---- */
1079
1080 static const struct tty_operations rfcomm_ops = {
1081         .open                   = rfcomm_tty_open,
1082         .close                  = rfcomm_tty_close,
1083         .write                  = rfcomm_tty_write,
1084         .write_room             = rfcomm_tty_write_room,
1085         .chars_in_buffer        = rfcomm_tty_chars_in_buffer,
1086         .flush_buffer           = rfcomm_tty_flush_buffer,
1087         .ioctl                  = rfcomm_tty_ioctl,
1088         .throttle               = rfcomm_tty_throttle,
1089         .unthrottle             = rfcomm_tty_unthrottle,
1090         .set_termios            = rfcomm_tty_set_termios,
1091         .send_xchar             = rfcomm_tty_send_xchar,
1092         .hangup                 = rfcomm_tty_hangup,
1093         .wait_until_sent        = rfcomm_tty_wait_until_sent,
1094         .read_proc              = rfcomm_tty_read_proc,
1095         .tiocmget               = rfcomm_tty_tiocmget,
1096         .tiocmset               = rfcomm_tty_tiocmset,
1097 };
1098
1099 int rfcomm_init_ttys(void)
1100 {
1101         rfcomm_tty_driver = alloc_tty_driver(RFCOMM_TTY_PORTS);
1102         if (!rfcomm_tty_driver)
1103                 return -1;
1104
1105         rfcomm_tty_driver->owner        = THIS_MODULE;
1106         rfcomm_tty_driver->driver_name  = "rfcomm";
1107         rfcomm_tty_driver->name         = "rfcomm";
1108         rfcomm_tty_driver->major        = RFCOMM_TTY_MAJOR;
1109         rfcomm_tty_driver->minor_start  = RFCOMM_TTY_MINOR;
1110         rfcomm_tty_driver->type         = TTY_DRIVER_TYPE_SERIAL;
1111         rfcomm_tty_driver->subtype      = SERIAL_TYPE_NORMAL;
1112         rfcomm_tty_driver->flags        = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
1113         rfcomm_tty_driver->init_termios = tty_std_termios;
1114         rfcomm_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
1115         tty_set_operations(rfcomm_tty_driver, &rfcomm_ops);
1116
1117         if (tty_register_driver(rfcomm_tty_driver)) {
1118                 BT_ERR("Can't register RFCOMM TTY driver");
1119                 put_tty_driver(rfcomm_tty_driver);
1120                 return -1;
1121         }
1122
1123         BT_INFO("RFCOMM TTY layer initialized");
1124
1125         return 0;
1126 }
1127
1128 void rfcomm_cleanup_ttys(void)
1129 {
1130         tty_unregister_driver(rfcomm_tty_driver);
1131         put_tty_driver(rfcomm_tty_driver);
1132 }