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/config.h>
  31 #include <linux/module.h>
  32
  33 #include <linux/tty.h>
  34 #include <linux/tty_driver.h>
  35 #include <linux/tty_flip.h>
  36
  37 #include <linux/slab.h>
  38 #include <linux/skbuff.h>
  39
  40 #include <net/bluetooth/bluetooth.h>
  41 #include <net/bluetooth/rfcomm.h>
  42
  43 #ifndef CONFIG_BT_RFCOMM_DEBUG
  44 #undef  BT_DBG
  45 #define BT_DBG(D...)
  46 #endif
  47
  48 #define RFCOMM_TTY_MAGIC 0x6d02         /* magic number for rfcomm struct */
  49 #define RFCOMM_TTY_PORTS RFCOMM_MAX_DEV /* whole lotta rfcomm devices */
  50 #define RFCOMM_TTY_MAJOR 216            /* device node major id of the usb/bluetooth.c driver */
  51 #define RFCOMM_TTY_MINOR 0
  52
  53 static struct tty_driver *rfcomm_tty_driver;
  54
  55 struct rfcomm_dev {
  56         struct list_head        list;
  57         atomic_t                refcnt;
  58
  59         char                    name[12];
  60         int                     id;
  61         unsigned long           flags;
  62         int                     opened;
  63         int                     err;
  64
  65         bdaddr_t                src;
  66         bdaddr_t                dst;
  67         u8                      channel;
  68
  69         uint                    modem_status;
  70
  71         struct rfcomm_dlc       *dlc;
  72         struct tty_struct       *tty;
  73         wait_queue_head_t       wait;
  74         struct tasklet_struct   wakeup_task;
  75
  76         atomic_t                wmem_alloc;
  77 };
  78
  79 static LIST_HEAD(rfcomm_dev_list);
  80 static DEFINE_RWLOCK(rfcomm_dev_lock);
  81
  82 static void rfcomm_dev_data_ready(struct rfcomm_dlc *dlc, struct sk_buff *skb);
  83 static void rfcomm_dev_state_change(struct rfcomm_dlc *dlc, int err);
  84 static void rfcomm_dev_modem_status(struct rfcomm_dlc *dlc, u8 v24_sig);
  85
  86 static void rfcomm_tty_wakeup(unsigned long arg);
  87
  88 /* ---- Device functions ---- */
  89 static void rfcomm_dev_destruct(struct rfcomm_dev *dev)
  90 {
  91         struct rfcomm_dlc *dlc = dev->dlc;
  92
  93         BT_DBG("dev %p dlc %p", dev, dlc);
  94
  95         rfcomm_dlc_lock(dlc);
  96         /* Detach DLC if it's owned by this dev */
  97         if (dlc->owner == dev)
  98                 dlc->owner = NULL;
  99         rfcomm_dlc_unlock(dlc);
 100
 101         rfcomm_dlc_put(dlc);
 102
 103         tty_unregister_device(rfcomm_tty_driver, dev->id);
 104
 105         /* Refcount should only hit zero when called from rfcomm_dev_del()
 106            which will have taken us off the list. Everything else are
 107            refcounting bugs. */
 108         BUG_ON(!list_empty(&dev->list));
 109
 110         kfree(dev);
 111
 112         /* It's safe to call module_put() here because socket still
 113            holds reference to this module. */
 114         module_put(THIS_MODULE);
 115 }
 116
 117 static inline void rfcomm_dev_hold(struct rfcomm_dev *dev)
 118 {
 119         atomic_inc(&dev->refcnt);
 120 }
 121
 122 static inline void rfcomm_dev_put(struct rfcomm_dev *dev)
 123 {
 124         /* The reason this isn't actually a race, as you no
 125            doubt have a little voice screaming at you in your
 126            head, is that the refcount should never actually
 127            reach zero unless the device has already been taken
 128            off the list, in rfcomm_dev_del(). And if that's not
 129            true, we'll hit the BUG() in rfcomm_dev_destruct()
 130            anyway. */
 131         if (atomic_dec_and_test(&dev->refcnt))
 132                 rfcomm_dev_destruct(dev);
 133 }
 134
 135 static struct rfcomm_dev *__rfcomm_dev_get(int id)
 136 {
 137         struct rfcomm_dev *dev;
 138         struct list_head  *p;
 139
 140         list_for_each(p, &rfcomm_dev_list) {
 141                 dev = list_entry(p, struct rfcomm_dev, list);
 142                 if (dev->id == id)
 143                         return dev;
 144         }
 145
 146         return NULL;
 147 }
 148
 149 static inline struct rfcomm_dev *rfcomm_dev_get(int id)
 150 {
 151         struct rfcomm_dev *dev;
 152
 153         read_lock(&rfcomm_dev_lock);
 154
 155         dev = __rfcomm_dev_get(id);
 156         if (dev)
 157                 rfcomm_dev_hold(dev);
 158
 159         read_unlock(&rfcomm_dev_lock);
 160
 161         return dev;
 162 }
 163
 164 static int rfcomm_dev_add(struct rfcomm_dev_req *req, struct rfcomm_dlc *dlc)
 165 {
 166         struct rfcomm_dev *dev;
 167         struct list_head *head = &rfcomm_dev_list, *p;
 168         int err = 0;
 169
 170         BT_DBG("id %d channel %d", req->dev_id, req->channel);
 171
 172         dev = kmalloc(sizeof(struct rfcomm_dev), GFP_KERNEL);
 173         if (!dev)
 174                 return -ENOMEM;
 175         memset(dev, 0, sizeof(struct rfcomm_dev));
 176
 177         write_lock_bh(&rfcomm_dev_lock);
 178
 179         if (req->dev_id < 0) {
 180                 dev->id = 0;
 181
 182                 list_for_each(p, &rfcomm_dev_list) {
 183                         if (list_entry(p, struct rfcomm_dev, list)->id != dev->id)
 184                                 break;
 185
 186                         dev->id++;
 187                         head = p;
 188                 }
 189         } else {
 190                 dev->id = req->dev_id;
 191
 192                 list_for_each(p, &rfcomm_dev_list) {
 193                         struct rfcomm_dev *entry = list_entry(p, struct rfcomm_dev, list);
 194
 195                         if (entry->id == dev->id) {
 196                                 err = -EADDRINUSE;
 197                                 goto out;
 198                         }
 199
 200                         if (entry->id > dev->id - 1)
 201                                 break;
 202
 203                         head = p;
 204                 }
 205         }
 206
 207         if ((dev->id < 0) || (dev->id > RFCOMM_MAX_DEV - 1)) {
 208                 err = -ENFILE;
 209                 goto out;
 210         }
 211
 212         sprintf(dev->name, "rfcomm%d", dev->id);
 213
 214         list_add(&dev->list, head);
 215         atomic_set(&dev->refcnt, 1);
 216
 217         bacpy(&dev->src, &req->src);
 218         bacpy(&dev->dst, &req->dst);
 219         dev->channel = req->channel;
 220
 221         dev->flags = req->flags &
 222                 ((1 << RFCOMM_RELEASE_ONHUP) | (1 << RFCOMM_REUSE_DLC));
 223
 224         init_waitqueue_head(&dev->wait);
 225         tasklet_init(&dev->wakeup_task, rfcomm_tty_wakeup, (unsigned long) dev);
 226
 227         rfcomm_dlc_lock(dlc);
 228         dlc->data_ready   = rfcomm_dev_data_ready;
 229         dlc->state_change = rfcomm_dev_state_change;
 230         dlc->modem_status = rfcomm_dev_modem_status;
 231
 232         dlc->owner = dev;
 233         dev->dlc   = dlc;
 234         rfcomm_dlc_unlock(dlc);
 235
 236         /* It's safe to call __module_get() here because socket already
 237            holds reference to this module. */
 238         __module_get(THIS_MODULE);
 239
 240 out:
 241         write_unlock_bh(&rfcomm_dev_lock);
 242
 243         if (err) {
 244                 kfree(dev);
 245                 return err;
 246         }
 247
 248         tty_register_device(rfcomm_tty_driver, dev->id, NULL);
 249
 250         return dev->id;
 251 }
 252
 253 static void rfcomm_dev_del(struct rfcomm_dev *dev)
 254 {
 255         BT_DBG("dev %p", dev);
 256
 257         write_lock_bh(&rfcomm_dev_lock);
 258         list_del_init(&dev->list);
 259         write_unlock_bh(&rfcomm_dev_lock);
 260
 261         rfcomm_dev_put(dev);
 262 }
 263
 264 /* ---- Send buffer ---- */
 265 static inline unsigned int rfcomm_room(struct rfcomm_dlc *dlc)
 266 {
 267         /* We can't let it be zero, because we don't get a callback
 268            when tx_credits becomes nonzero, hence we'd never wake up */
 269         return dlc->mtu * (dlc->tx_credits?:1);
 270 }
 271
 272 static void rfcomm_wfree(struct sk_buff *skb)
 273 {
 274         struct rfcomm_dev *dev = (void *) skb->sk;
 275         atomic_sub(skb->truesize, &dev->wmem_alloc);
 276         if (test_bit(RFCOMM_TTY_ATTACHED, &dev->flags))
 277                 tasklet_schedule(&dev->wakeup_task);
 278         rfcomm_dev_put(dev);
 279 }
 280
 281 static inline void rfcomm_set_owner_w(struct sk_buff *skb, struct rfcomm_dev *dev)
 282 {
 283         rfcomm_dev_hold(dev);
 284         atomic_add(skb->truesize, &dev->wmem_alloc);
 285         skb->sk = (void *) dev;
 286         skb->destructor = rfcomm_wfree;
 287 }
 288
 289 static struct sk_buff *rfcomm_wmalloc(struct rfcomm_dev *dev, unsigned long size, int priority)
 290 {
 291         if (atomic_read(&dev->wmem_alloc) < rfcomm_room(dev->dlc)) {
 292                 struct sk_buff *skb = alloc_skb(size, priority);
 293                 if (skb) {
 294                         rfcomm_set_owner_w(skb, dev);
 295                         return skb;
 296                 }
 297         }
 298         return NULL;
 299 }
 300
 301 /* ---- Device IOCTLs ---- */
 302
 303 #define NOCAP_FLAGS ((1 << RFCOMM_REUSE_DLC) | (1 << RFCOMM_RELEASE_ONHUP))
 304
 305 static int rfcomm_create_dev(struct sock *sk, void __user *arg)
 306 {
 307         struct rfcomm_dev_req req;
 308         struct rfcomm_dlc *dlc;
 309         int id;
 310
 311         if (copy_from_user(&req, arg, sizeof(req)))
 312                 return -EFAULT;
 313
 314         BT_DBG("sk %p dev_id %id flags 0x%x", sk, req.dev_id, req.flags);
 315
 316         if (req.flags != NOCAP_FLAGS && !capable(CAP_NET_ADMIN))
 317                 return -EPERM;
 318
 319         if (req.flags & (1 << RFCOMM_REUSE_DLC)) {
 320                 /* Socket must be connected */
 321                 if (sk->sk_state != BT_CONNECTED)
 322                         return -EBADFD;
 323
 324                 dlc = rfcomm_pi(sk)->dlc;
 325                 rfcomm_dlc_hold(dlc);
 326         } else {
 327                 dlc = rfcomm_dlc_alloc(GFP_KERNEL);
 328                 if (!dlc)
 329                         return -ENOMEM;
 330         }
 331
 332         id = rfcomm_dev_add(&req, dlc);
 333         if (id < 0) {
 334                 rfcomm_dlc_put(dlc);
 335                 return id;
 336         }
 337
 338         if (req.flags & (1 << RFCOMM_REUSE_DLC)) {
 339                 /* DLC is now used by device.
 340                  * Socket must be disconnected */
 341                 sk->sk_state = BT_CLOSED;
 342         }
 343
 344         return id;
 345 }
 346
 347 static int rfcomm_release_dev(void __user *arg)
 348 {
 349         struct rfcomm_dev_req req;
 350         struct rfcomm_dev *dev;
 351
 352         if (copy_from_user(&req, arg, sizeof(req)))
 353                 return -EFAULT;
 354
 355         BT_DBG("dev_id %id flags 0x%x", req.dev_id, req.flags);
 356
 357         if (!(dev = rfcomm_dev_get(req.dev_id)))
 358                 return -ENODEV;
 359
 360         if (dev->flags != NOCAP_FLAGS && !capable(CAP_NET_ADMIN)) {
 361                 rfcomm_dev_put(dev);
 362                 return -EPERM;
 363         }
 364
 365         if (req.flags & (1 << RFCOMM_HANGUP_NOW))
 366                 rfcomm_dlc_close(dev->dlc, 0);
 367
 368         rfcomm_dev_del(dev);
 369         rfcomm_dev_put(dev);
 370         return 0;
 371 }
 372
 373 static int rfcomm_get_dev_list(void __user *arg)
 374 {
 375         struct rfcomm_dev_list_req *dl;
 376         struct rfcomm_dev_info *di;
 377         struct list_head *p;
 378         int n = 0, size, err;
 379         u16 dev_num;
 380
 381         BT_DBG("");
 382
 383         if (get_user(dev_num, (u16 __user *) arg))
 384                 return -EFAULT;
 385
 386         if (!dev_num || dev_num > (PAGE_SIZE * 4) / sizeof(*di))
 387                 return -EINVAL;
 388
 389         size = sizeof(*dl) + dev_num * sizeof(*di);
 390
 391         if (!(dl = kmalloc(size, GFP_KERNEL)))
 392                 return -ENOMEM;
 393
 394         di = dl->dev_info;
 395
 396         read_lock_bh(&rfcomm_dev_lock);
 397
 398         list_for_each(p, &rfcomm_dev_list) {
 399                 struct rfcomm_dev *dev = list_entry(p, struct rfcomm_dev, list);
 400                 (di + n)->id      = dev->id;
 401                 (di + n)->flags   = dev->flags;
 402                 (di + n)->state   = dev->dlc->state;
 403                 (di + n)->channel = dev->channel;
 404                 bacpy(&(di + n)->src, &dev->src);
 405                 bacpy(&(di + n)->dst, &dev->dst);
 406                 if (++n >= dev_num)
 407                         break;
 408         }
 409
 410         read_unlock_bh(&rfcomm_dev_lock);
 411
 412         dl->dev_num = n;
 413         size = sizeof(*dl) + n * sizeof(*di);
 414
 415         err = copy_to_user(arg, dl, size);
 416         kfree(dl);
 417
 418         return err ? -EFAULT : 0;
 419 }
 420
 421 static int rfcomm_get_dev_info(void __user *arg)
 422 {
 423         struct rfcomm_dev *dev;
 424         struct rfcomm_dev_info di;
 425         int err = 0;
 426
 427         BT_DBG("");
 428
 429         if (copy_from_user(&di, arg, sizeof(di)))
 430                 return -EFAULT;
 431
 432         if (!(dev = rfcomm_dev_get(di.id)))
 433                 return -ENODEV;
 434
 435         di.flags   = dev->flags;
 436         di.channel = dev->channel;
 437         di.state   = dev->dlc->state;
 438         bacpy(&di.src, &dev->src);
 439         bacpy(&di.dst, &dev->dst);
 440
 441         if (copy_to_user(arg, &di, sizeof(di)))
 442                 err = -EFAULT;
 443
 444         rfcomm_dev_put(dev);
 445         return err;
 446 }
 447
 448 int rfcomm_dev_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
 449 {
 450         BT_DBG("cmd %d arg %p", cmd, arg);
 451
 452         switch (cmd) {
 453         case RFCOMMCREATEDEV:
 454                 return rfcomm_create_dev(sk, arg);
 455
 456         case RFCOMMRELEASEDEV:
 457                 return rfcomm_release_dev(arg);
 458
 459         case RFCOMMGETDEVLIST:
 460                 return rfcomm_get_dev_list(arg);
 461
 462         case RFCOMMGETDEVINFO:
 463                 return rfcomm_get_dev_info(arg);
 464         }
 465
 466         return -EINVAL;
 467 }
 468
 469 /* ---- DLC callbacks ---- */
 470 static void rfcomm_dev_data_ready(struct rfcomm_dlc *dlc, struct sk_buff *skb)
 471 {
 472         struct rfcomm_dev *dev = dlc->owner;
 473         struct tty_struct *tty;
 474
 475         if (!dev || !(tty = dev->tty)) {
 476                 kfree_skb(skb);
 477                 return;
 478         }
 479
 480         BT_DBG("dlc %p tty %p len %d", dlc, tty, skb->len);
 481
 482         if (test_bit(TTY_DONT_FLIP, &tty->flags)) {
 483                 register int i;
 484                 for (i = 0; i < skb->len; i++) {
 485                         if (tty->flip.count >= TTY_FLIPBUF_SIZE)
 486                                 tty_flip_buffer_push(tty);
 487
 488                         tty_insert_flip_char(tty, skb->data[i], 0);
 489                 }
 490                 tty_flip_buffer_push(tty);
 491         } else
 492                 tty->ldisc.receive_buf(tty, skb->data, NULL, skb->len);
 493
 494         kfree_skb(skb);
 495 }
 496
 497 static void rfcomm_dev_state_change(struct rfcomm_dlc *dlc, int err)
 498 {
 499         struct rfcomm_dev *dev = dlc->owner;
 500         if (!dev)
 501                 return;
 502
 503         BT_DBG("dlc %p dev %p err %d", dlc, dev, err);
 504
 505         dev->err = err;
 506         wake_up_interruptible(&dev->wait);
 507
 508         if (dlc->state == BT_CLOSED) {
 509                 if (!dev->tty) {
 510                         if (test_bit(RFCOMM_RELEASE_ONHUP, &dev->flags)) {
 511                                 rfcomm_dev_hold(dev);
 512                                 rfcomm_dev_del(dev);
 513
 514                                 /* We have to drop DLC lock here, otherwise
 515                                    rfcomm_dev_put() will dead lock if it's
 516                                    the last reference. */
 517                                 rfcomm_dlc_unlock(dlc);
 518                                 rfcomm_dev_put(dev);
 519                                 rfcomm_dlc_lock(dlc);
 520                         }
 521                 } else
 522                         tty_hangup(dev->tty);
 523         }
 524 }
 525
 526 static void rfcomm_dev_modem_status(struct rfcomm_dlc *dlc, u8 v24_sig)
 527 {
 528         struct rfcomm_dev *dev = dlc->owner;
 529         if (!dev)
 530                 return;
 531
 532         BT_DBG("dlc %p dev %p v24_sig 0x%02x", dlc, dev, v24_sig);
 533
 534         dev->modem_status =
 535                 ((v24_sig & RFCOMM_V24_RTC) ? (TIOCM_DSR | TIOCM_DTR) : 0) |
 536                 ((v24_sig & RFCOMM_V24_RTR) ? (TIOCM_RTS | TIOCM_CTS) : 0) |
 537                 ((v24_sig & RFCOMM_V24_IC)  ? TIOCM_RI : 0) |
 538                 ((v24_sig & RFCOMM_V24_DV)  ? TIOCM_CD : 0);
 539 }
 540
 541 /* ---- TTY functions ---- */
 542 static void rfcomm_tty_wakeup(unsigned long arg)
 543 {
 544         struct rfcomm_dev *dev = (void *) arg;
 545         struct tty_struct *tty = dev->tty;
 546         if (!tty)
 547                 return;
 548
 549         BT_DBG("dev %p tty %p", dev, tty);
 550
 551         if (test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags) && tty->ldisc.write_wakeup)
 552                 (tty->ldisc.write_wakeup)(tty);
 553
 554         wake_up_interruptible(&tty->write_wait);
 555 #ifdef SERIAL_HAVE_POLL_WAIT
 556         wake_up_interruptible(&tty->poll_wait);
 557 #endif
 558 }
 559
 560 static int rfcomm_tty_open(struct tty_struct *tty, struct file *filp)
 561 {
 562         DECLARE_WAITQUEUE(wait, current);
 563         struct rfcomm_dev *dev;
 564         struct rfcomm_dlc *dlc;
 565         int err, id;
 566
 567         id = tty->index;
 568
 569         BT_DBG("tty %p id %d", tty, id);
 570
 571         /* We don't leak this refcount. For reasons which are not entirely
 572            clear, the TTY layer will call our ->close() method even if the
 573            open fails. We decrease the refcount there, and decreasing it
 574            here too would cause breakage. */
 575         dev = rfcomm_dev_get(id);
 576         if (!dev)
 577                 return -ENODEV;
 578
 579         BT_DBG("dev %p dst %s channel %d opened %d", dev, batostr(&dev->dst), dev->channel, dev->opened);
 580
 581         if (dev->opened++ != 0)
 582                 return 0;
 583
 584         dlc = dev->dlc;
 585
 586         /* Attach TTY and open DLC */
 587
 588         rfcomm_dlc_lock(dlc);
 589         tty->driver_data = dev;
 590         dev->tty = tty;
 591         rfcomm_dlc_unlock(dlc);
 592         set_bit(RFCOMM_TTY_ATTACHED, &dev->flags);
 593
 594         err = rfcomm_dlc_open(dlc, &dev->src, &dev->dst, dev->channel);
 595         if (err < 0)
 596                 return err;
 597
 598         /* Wait for DLC to connect */
 599         add_wait_queue(&dev->wait, &wait);
 600         while (1) {
 601                 set_current_state(TASK_INTERRUPTIBLE);
 602
 603                 if (dlc->state == BT_CLOSED) {
 604                         err = -dev->err;
 605                         break;
 606                 }
 607
 608                 if (dlc->state == BT_CONNECTED)
 609                         break;
 610
 611                 if (signal_pending(current)) {
 612                         err = -EINTR;
 613                         break;
 614                 }
 615
 616                 schedule();
 617         }
 618         set_current_state(TASK_RUNNING);
 619         remove_wait_queue(&dev->wait, &wait);
 620
 621         return err;
 622 }
 623
 624 static void rfcomm_tty_close(struct tty_struct *tty, struct file *filp)
 625 {
 626         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
 627         if (!dev)
 628                 return;
 629
 630         BT_DBG("tty %p dev %p dlc %p opened %d", tty, dev, dev->dlc, dev->opened);
 631
 632         if (--dev->opened == 0) {
 633                 /* Close DLC and dettach TTY */
 634                 rfcomm_dlc_close(dev->dlc, 0);
 635
 636                 clear_bit(RFCOMM_TTY_ATTACHED, &dev->flags);
 637                 tasklet_kill(&dev->wakeup_task);
 638
 639                 rfcomm_dlc_lock(dev->dlc);
 640                 tty->driver_data = NULL;
 641                 dev->tty = NULL;
 642                 rfcomm_dlc_unlock(dev->dlc);
 643         }
 644
 645         rfcomm_dev_put(dev);
 646 }
 647
 648 static int rfcomm_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
 649 {
 650         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
 651         struct rfcomm_dlc *dlc = dev->dlc;
 652         struct sk_buff *skb;
 653         int err = 0, sent = 0, size;
 654
 655         BT_DBG("tty %p count %d", tty, count);
 656
 657         while (count) {
 658                 size = min_t(uint, count, dlc->mtu);
 659
 660                 skb = rfcomm_wmalloc(dev, size + RFCOMM_SKB_RESERVE, GFP_ATOMIC);
 661
 662                 if (!skb)
 663                         break;
 664
 665                 skb_reserve(skb, RFCOMM_SKB_HEAD_RESERVE);
 666
 667                 memcpy(skb_put(skb, size), buf + sent, size);
 668
 669                 if ((err = rfcomm_dlc_send(dlc, skb)) < 0) {
 670                         kfree_skb(skb);
 671                         break;
 672                 }
 673
 674                 sent  += size;
 675                 count -= size;
 676         }
 677
 678         return sent ? sent : err;
 679 }
 680
 681 static int rfcomm_tty_write_room(struct tty_struct *tty)
 682 {
 683         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
 684         int room;
 685
 686         BT_DBG("tty %p", tty);
 687
 688         room = rfcomm_room(dev->dlc) - atomic_read(&dev->wmem_alloc);
 689         if (room < 0)
 690                 room = 0;
 691         return room;
 692 }
 693
 694 static int rfcomm_tty_ioctl(struct tty_struct *tty, struct file *filp, unsigned int cmd, unsigned long arg)
 695 {
 696         BT_DBG("tty %p cmd 0x%02x", tty, cmd);
 697
 698         switch (cmd) {
 699         case TCGETS:
 700                 BT_DBG("TCGETS is not supported");
 701                 return -ENOIOCTLCMD;
 702
 703         case TCSETS:
 704                 BT_DBG("TCSETS is not supported");
 705                 return -ENOIOCTLCMD;
 706
 707         case TIOCMIWAIT:
 708                 BT_DBG("TIOCMIWAIT");
 709                 break;
 710
 711         case TIOCGICOUNT:
 712                 BT_DBG("TIOCGICOUNT");
 713                 break;
 714
 715         case TIOCGSERIAL:
 716                 BT_ERR("TIOCGSERIAL is not supported");
 717                 return -ENOIOCTLCMD;
 718
 719         case TIOCSSERIAL:
 720                 BT_ERR("TIOCSSERIAL is not supported");
 721                 return -ENOIOCTLCMD;
 722
 723         case TIOCSERGSTRUCT:
 724                 BT_ERR("TIOCSERGSTRUCT is not supported");
 725                 return -ENOIOCTLCMD;
 726
 727         case TIOCSERGETLSR:
 728                 BT_ERR("TIOCSERGETLSR is not supported");
 729                 return -ENOIOCTLCMD;
 730
 731         case TIOCSERCONFIG:
 732                 BT_ERR("TIOCSERCONFIG is not supported");
 733                 return -ENOIOCTLCMD;
 734
 735         default:
 736                 return -ENOIOCTLCMD;    /* ioctls which we must ignore */
 737
 738         }
 739
 740         return -ENOIOCTLCMD;
 741 }
 742
 743 #define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
 744
 745 static void rfcomm_tty_set_termios(struct tty_struct *tty, struct termios *old)
 746 {
 747         BT_DBG("tty %p", tty);
 748
 749         if ((tty->termios->c_cflag == old->c_cflag) &&
 750                 (RELEVANT_IFLAG(tty->termios->c_iflag) == RELEVANT_IFLAG(old->c_iflag)))
 751                 return;
 752
 753         /* handle turning off CRTSCTS */
 754         if ((old->c_cflag & CRTSCTS) && !(tty->termios->c_cflag & CRTSCTS)) {
 755                 BT_DBG("turning off CRTSCTS");
 756         }
 757 }
 758
 759 static void rfcomm_tty_throttle(struct tty_struct *tty)
 760 {
 761         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
 762
 763         BT_DBG("tty %p dev %p", tty, dev);
 764
 765         rfcomm_dlc_throttle(dev->dlc);
 766 }
 767
 768 static void rfcomm_tty_unthrottle(struct tty_struct *tty)
 769 {
 770         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
 771
 772         BT_DBG("tty %p dev %p", tty, dev);
 773
 774         rfcomm_dlc_unthrottle(dev->dlc);
 775 }
 776
 777 static int rfcomm_tty_chars_in_buffer(struct tty_struct *tty)
 778 {
 779         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
 780         struct rfcomm_dlc *dlc = dev->dlc;
 781
 782         BT_DBG("tty %p dev %p", tty, dev);
 783
 784         if (skb_queue_len(&dlc->tx_queue))
 785                 return dlc->mtu;
 786
 787         return 0;
 788 }
 789
 790 static void rfcomm_tty_flush_buffer(struct tty_struct *tty)
 791 {
 792         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
 793         if (!dev)
 794                 return;
 795
 796         BT_DBG("tty %p dev %p", tty, dev);
 797
 798         skb_queue_purge(&dev->dlc->tx_queue);
 799
 800         if (test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags) && tty->ldisc.write_wakeup)
 801                 tty->ldisc.write_wakeup(tty);
 802 }
 803
 804 static void rfcomm_tty_send_xchar(struct tty_struct *tty, char ch)
 805 {
 806         BT_DBG("tty %p ch %c", tty, ch);
 807 }
 808
 809 static void rfcomm_tty_wait_until_sent(struct tty_struct *tty, int timeout)
 810 {
 811         BT_DBG("tty %p timeout %d", tty, timeout);
 812 }
 813
 814 static void rfcomm_tty_hangup(struct tty_struct *tty)
 815 {
 816         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
 817         if (!dev)
 818                 return;
 819
 820         BT_DBG("tty %p dev %p", tty, dev);
 821
 822         rfcomm_tty_flush_buffer(tty);
 823
 824         if (test_bit(RFCOMM_RELEASE_ONHUP, &dev->flags))
 825                 rfcomm_dev_del(dev);
 826 }
 827
 828 static int rfcomm_tty_read_proc(char *buf, char **start, off_t offset, int len, int *eof, void *unused)
 829 {
 830         return 0;
 831 }
 832
 833 static int rfcomm_tty_tiocmget(struct tty_struct *tty, struct file *filp)
 834 {
 835         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
 836
 837         BT_DBG("tty %p dev %p", tty, dev);
 838
 839         return dev->modem_status;
 840 }
 841
 842 static int rfcomm_tty_tiocmset(struct tty_struct *tty, struct file *filp, unsigned int set, unsigned int clear)
 843 {
 844         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
 845         struct rfcomm_dlc *dlc = dev->dlc;
 846         u8 v24_sig;
 847
 848         BT_DBG("tty %p dev %p set 0x%02x clear 0x%02x", tty, dev, set, clear);
 849
 850         rfcomm_dlc_get_modem_status(dlc, &v24_sig);
 851
 852         if (set & TIOCM_DSR || set & TIOCM_DTR)
 853                 v24_sig |= RFCOMM_V24_RTC;
 854         if (set & TIOCM_RTS || set & TIOCM_CTS)
 855                 v24_sig |= RFCOMM_V24_RTR;
 856         if (set & TIOCM_RI)
 857                 v24_sig |= RFCOMM_V24_IC;
 858         if (set & TIOCM_CD)
 859                 v24_sig |= RFCOMM_V24_DV;
 860
 861         if (clear & TIOCM_DSR || clear & TIOCM_DTR)
 862                 v24_sig &= ~RFCOMM_V24_RTC;
 863         if (clear & TIOCM_RTS || clear & TIOCM_CTS)
 864                 v24_sig &= ~RFCOMM_V24_RTR;
 865         if (clear & TIOCM_RI)
 866                 v24_sig &= ~RFCOMM_V24_IC;
 867         if (clear & TIOCM_CD)
 868                 v24_sig &= ~RFCOMM_V24_DV;
 869
 870         rfcomm_dlc_set_modem_status(dlc, v24_sig);
 871
 872         return 0;
 873 }
 874
 875 /* ---- TTY structure ---- */
 876
 877 static struct tty_operations rfcomm_ops = {
 878         .open                   = rfcomm_tty_open,
 879         .close                  = rfcomm_tty_close,
 880         .write                  = rfcomm_tty_write,
 881         .write_room             = rfcomm_tty_write_room,
 882         .chars_in_buffer        = rfcomm_tty_chars_in_buffer,
 883         .flush_buffer           = rfcomm_tty_flush_buffer,
 884         .ioctl                  = rfcomm_tty_ioctl,
 885         .throttle               = rfcomm_tty_throttle,
 886         .unthrottle             = rfcomm_tty_unthrottle,
 887         .set_termios            = rfcomm_tty_set_termios,
 888         .send_xchar             = rfcomm_tty_send_xchar,
 889         .hangup                 = rfcomm_tty_hangup,
 890         .wait_until_sent        = rfcomm_tty_wait_until_sent,
 891         .read_proc              = rfcomm_tty_read_proc,
 892         .tiocmget               = rfcomm_tty_tiocmget,
 893         .tiocmset               = rfcomm_tty_tiocmset,
 894 };
 895
 896 int rfcomm_init_ttys(void)
 897 {
 898         rfcomm_tty_driver = alloc_tty_driver(RFCOMM_TTY_PORTS);
 899         if (!rfcomm_tty_driver)
 900                 return -1;
 901
 902         rfcomm_tty_driver->owner        = THIS_MODULE;
 903         rfcomm_tty_driver->driver_name  = "rfcomm";
 904         rfcomm_tty_driver->devfs_name   = "bluetooth/rfcomm/";
 905         rfcomm_tty_driver->name         = "rfcomm";
 906         rfcomm_tty_driver->major        = RFCOMM_TTY_MAJOR;
 907         rfcomm_tty_driver->minor_start  = RFCOMM_TTY_MINOR;
 908         rfcomm_tty_driver->type         = TTY_DRIVER_TYPE_SERIAL;
 909         rfcomm_tty_driver->subtype      = SERIAL_TYPE_NORMAL;
 910         rfcomm_tty_driver->flags        = TTY_DRIVER_REAL_RAW | TTY_DRIVER_NO_DEVFS;
 911         rfcomm_tty_driver->init_termios = tty_std_termios;
 912         rfcomm_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
 913         tty_set_operations(rfcomm_tty_driver, &rfcomm_ops);
 914
 915         if (tty_register_driver(rfcomm_tty_driver)) {
 916                 BT_ERR("Can't register RFCOMM TTY driver");
 917                 put_tty_driver(rfcomm_tty_driver);
 918                 return -1;
 919         }
 920
 921         BT_INFO("RFCOMM TTY layer initialized");
 922
 923         return 0;
 924 }
 925
 926 void rfcomm_cleanup_ttys(void)
 927 {
 928         tty_unregister_driver(rfcomm_tty_driver);
 929         put_tty_driver(rfcomm_tty_driver);
 930 }