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
  28 #include <linux/module.h>
  29
  30 #include <linux/tty.h>
  31 #include <linux/tty_driver.h>
  32 #include <linux/tty_flip.h>
  33
  34 #include <linux/capability.h>
  35 #include <linux/slab.h>
  36 #include <linux/skbuff.h>
  37
  38 #include <net/bluetooth/bluetooth.h>
  39 #include <net/bluetooth/hci_core.h>
  40 #include <net/bluetooth/rfcomm.h>
  41
  42 #define RFCOMM_TTY_MAGIC 0x6d02         /* magic number for rfcomm struct */
  43 #define RFCOMM_TTY_PORTS RFCOMM_MAX_DEV /* whole lotta rfcomm devices */
  44 #define RFCOMM_TTY_MAJOR 216            /* device node major id of the usb/bluetooth.c driver */
  45 #define RFCOMM_TTY_MINOR 0
  46
  47 static struct tty_driver *rfcomm_tty_driver;
  48
  49 struct rfcomm_dev {
  50         struct list_head        list;
  51         atomic_t                refcnt;
  52
  53         char                    name[12];
  54         int                     id;
  55         unsigned long           flags;
  56         atomic_t                opened;
  57         int                     err;
  58
  59         bdaddr_t                src;
  60         bdaddr_t                dst;
  61         u8                      channel;
  62
  63         uint                    modem_status;
  64
  65         struct rfcomm_dlc       *dlc;
  66         struct tty_struct       *tty;
  67         wait_queue_head_t       wait;
  68         struct tasklet_struct   wakeup_task;
  69
  70         struct device           *tty_dev;
  71
  72         atomic_t                wmem_alloc;
  73
  74         struct sk_buff_head     pending;
  75 };
  76
  77 static LIST_HEAD(rfcomm_dev_list);
  78 static DEFINE_RWLOCK(rfcomm_dev_lock);
  79
  80 static void rfcomm_dev_data_ready(struct rfcomm_dlc *dlc, struct sk_buff *skb);
  81 static void rfcomm_dev_state_change(struct rfcomm_dlc *dlc, int err);
  82 static void rfcomm_dev_modem_status(struct rfcomm_dlc *dlc, u8 v24_sig);
  83
  84 static void rfcomm_tty_wakeup(unsigned long arg);
  85
  86 /* ---- Device functions ---- */
  87 static void rfcomm_dev_destruct(struct rfcomm_dev *dev)
  88 {
  89         struct rfcomm_dlc *dlc = dev->dlc;
  90
  91         BT_DBG("dev %p dlc %p", dev, dlc);
  92
  93         /* Refcount should only hit zero when called from rfcomm_dev_del()
  94            which will have taken us off the list. Everything else are
  95            refcounting bugs. */
  96         BUG_ON(!list_empty(&dev->list));
  97
  98         rfcomm_dlc_lock(dlc);
  99         /* Detach DLC if it's owned by this dev */
 100         if (dlc->owner == dev)
 101                 dlc->owner = NULL;
 102         rfcomm_dlc_unlock(dlc);
 103
 104         rfcomm_dlc_put(dlc);
 105
 106         tty_unregister_device(rfcomm_tty_driver, dev->id);
 107
 108         kfree(dev);
 109
 110         /* It's safe to call module_put() here because socket still
 111            holds reference to this module. */
 112         module_put(THIS_MODULE);
 113 }
 114
 115 static inline void rfcomm_dev_hold(struct rfcomm_dev *dev)
 116 {
 117         atomic_inc(&dev->refcnt);
 118 }
 119
 120 static inline void rfcomm_dev_put(struct rfcomm_dev *dev)
 121 {
 122         /* The reason this isn't actually a race, as you no
 123            doubt have a little voice screaming at you in your
 124            head, is that the refcount should never actually
 125            reach zero unless the device has already been taken
 126            off the list, in rfcomm_dev_del(). And if that's not
 127            true, we'll hit the BUG() in rfcomm_dev_destruct()
 128            anyway. */
 129         if (atomic_dec_and_test(&dev->refcnt))
 130                 rfcomm_dev_destruct(dev);
 131 }
 132
 133 static struct rfcomm_dev *__rfcomm_dev_get(int id)
 134 {
 135         struct rfcomm_dev *dev;
 136         struct list_head  *p;
 137
 138         list_for_each(p, &rfcomm_dev_list) {
 139                 dev = list_entry(p, struct rfcomm_dev, list);
 140                 if (dev->id == id)
 141                         return dev;
 142         }
 143
 144         return NULL;
 145 }
 146
 147 static inline struct rfcomm_dev *rfcomm_dev_get(int id)
 148 {
 149         struct rfcomm_dev *dev;
 150
 151         read_lock(&rfcomm_dev_lock);
 152
 153         dev = __rfcomm_dev_get(id);
 154
 155         if (dev) {
 156                 if (test_bit(RFCOMM_TTY_RELEASED, &dev->flags))
 157                         dev = NULL;
 158                 else
 159                         rfcomm_dev_hold(dev);
 160         }
 161
 162         read_unlock(&rfcomm_dev_lock);
 163
 164         return dev;
 165 }
 166
 167 static struct device *rfcomm_get_device(struct rfcomm_dev *dev)
 168 {
 169         struct hci_dev *hdev;
 170         struct hci_conn *conn;
 171
 172         hdev = hci_get_route(&dev->dst, &dev->src);
 173         if (!hdev)
 174                 return NULL;
 175
 176         conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &dev->dst);
 177
 178         hci_dev_put(hdev);
 179
 180         return conn ? &conn->dev : NULL;
 181 }
 182
 183 static ssize_t show_address(struct device *tty_dev, struct device_attribute *attr, char *buf)
 184 {
 185         struct rfcomm_dev *dev = dev_get_drvdata(tty_dev);
 186         return sprintf(buf, "%s\n", batostr(&dev->dst));
 187 }
 188
 189 static ssize_t show_channel(struct device *tty_dev, struct device_attribute *attr, char *buf)
 190 {
 191         struct rfcomm_dev *dev = dev_get_drvdata(tty_dev);
 192         return sprintf(buf, "%d\n", dev->channel);
 193 }
 194
 195 static DEVICE_ATTR(address, S_IRUGO, show_address, NULL);
 196 static DEVICE_ATTR(channel, S_IRUGO, show_channel, NULL);
 197
 198 static int rfcomm_dev_add(struct rfcomm_dev_req *req, struct rfcomm_dlc *dlc)
 199 {
 200         struct rfcomm_dev *dev;
 201         struct list_head *head = &rfcomm_dev_list, *p;
 202         int err = 0;
 203
 204         BT_DBG("id %d channel %d", req->dev_id, req->channel);
 205
 206         dev = kzalloc(sizeof(struct rfcomm_dev), GFP_KERNEL);
 207         if (!dev)
 208                 return -ENOMEM;
 209
 210         write_lock_bh(&rfcomm_dev_lock);
 211
 212         if (req->dev_id < 0) {
 213                 dev->id = 0;
 214
 215                 list_for_each(p, &rfcomm_dev_list) {
 216                         if (list_entry(p, struct rfcomm_dev, list)->id != dev->id)
 217                                 break;
 218
 219                         dev->id++;
 220                         head = p;
 221                 }
 222         } else {
 223                 dev->id = req->dev_id;
 224
 225                 list_for_each(p, &rfcomm_dev_list) {
 226                         struct rfcomm_dev *entry = list_entry(p, struct rfcomm_dev, list);
 227
 228                         if (entry->id == dev->id) {
 229                                 err = -EADDRINUSE;
 230                                 goto out;
 231                         }
 232
 233                         if (entry->id > dev->id - 1)
 234                                 break;
 235
 236                         head = p;
 237                 }
 238         }
 239
 240         if ((dev->id < 0) || (dev->id > RFCOMM_MAX_DEV - 1)) {
 241                 err = -ENFILE;
 242                 goto out;
 243         }
 244
 245         sprintf(dev->name, "rfcomm%d", dev->id);
 246
 247         list_add(&dev->list, head);
 248         atomic_set(&dev->refcnt, 1);
 249
 250         bacpy(&dev->src, &req->src);
 251         bacpy(&dev->dst, &req->dst);
 252         dev->channel = req->channel;
 253
 254         dev->flags = req->flags &
 255                 ((1 << RFCOMM_RELEASE_ONHUP) | (1 << RFCOMM_REUSE_DLC));
 256
 257         atomic_set(&dev->opened, 0);
 258
 259         init_waitqueue_head(&dev->wait);
 260         tasklet_init(&dev->wakeup_task, rfcomm_tty_wakeup, (unsigned long) dev);
 261
 262         skb_queue_head_init(&dev->pending);
 263
 264         rfcomm_dlc_lock(dlc);
 265
 266         if (req->flags & (1 << RFCOMM_REUSE_DLC)) {
 267                 struct sock *sk = dlc->owner;
 268                 struct sk_buff *skb;
 269
 270                 BUG_ON(!sk);
 271
 272                 rfcomm_dlc_throttle(dlc);
 273
 274                 while ((skb = skb_dequeue(&sk->sk_receive_queue))) {
 275                         skb_orphan(skb);
 276                         skb_queue_tail(&dev->pending, skb);
 277                         atomic_sub(skb->len, &sk->sk_rmem_alloc);
 278                 }
 279         }
 280
 281         dlc->data_ready   = rfcomm_dev_data_ready;
 282         dlc->state_change = rfcomm_dev_state_change;
 283         dlc->modem_status = rfcomm_dev_modem_status;
 284
 285         dlc->owner = dev;
 286         dev->dlc   = dlc;
 287
 288         rfcomm_dev_modem_status(dlc, dlc->remote_v24_sig);
 289
 290         rfcomm_dlc_unlock(dlc);
 291
 292         /* It's safe to call __module_get() here because socket already
 293            holds reference to this module. */
 294         __module_get(THIS_MODULE);
 295
 296 out:
 297         write_unlock_bh(&rfcomm_dev_lock);
 298
 299         if (err < 0)
 300                 goto free;
 301
 302         dev->tty_dev = tty_register_device(rfcomm_tty_driver, dev->id, NULL);
 303
 304         if (IS_ERR(dev->tty_dev)) {
 305                 err = PTR_ERR(dev->tty_dev);
 306                 list_del(&dev->list);
 307                 goto free;
 308         }
 309
 310         dev_set_drvdata(dev->tty_dev, dev);
 311
 312         if (device_create_file(dev->tty_dev, &dev_attr_address) < 0)
 313                 BT_ERR("Failed to create address attribute");
 314
 315         if (device_create_file(dev->tty_dev, &dev_attr_channel) < 0)
 316                 BT_ERR("Failed to create channel attribute");
 317
 318         return dev->id;
 319
 320 free:
 321         kfree(dev);
 322         return err;
 323 }
 324
 325 static void rfcomm_dev_del(struct rfcomm_dev *dev)
 326 {
 327         BT_DBG("dev %p", dev);
 328
 329         BUG_ON(test_and_set_bit(RFCOMM_TTY_RELEASED, &dev->flags));
 330
 331         if (atomic_read(&dev->opened) > 0)
 332                 return;
 333
 334         write_lock_bh(&rfcomm_dev_lock);
 335         list_del_init(&dev->list);
 336         write_unlock_bh(&rfcomm_dev_lock);
 337
 338         rfcomm_dev_put(dev);
 339 }
 340
 341 /* ---- Send buffer ---- */
 342 static inline unsigned int rfcomm_room(struct rfcomm_dlc *dlc)
 343 {
 344         /* We can't let it be zero, because we don't get a callback
 345            when tx_credits becomes nonzero, hence we'd never wake up */
 346         return dlc->mtu * (dlc->tx_credits?:1);
 347 }
 348
 349 static void rfcomm_wfree(struct sk_buff *skb)
 350 {
 351         struct rfcomm_dev *dev = (void *) skb->sk;
 352         atomic_sub(skb->truesize, &dev->wmem_alloc);
 353         if (test_bit(RFCOMM_TTY_ATTACHED, &dev->flags))
 354                 tasklet_schedule(&dev->wakeup_task);
 355         rfcomm_dev_put(dev);
 356 }
 357
 358 static inline void rfcomm_set_owner_w(struct sk_buff *skb, struct rfcomm_dev *dev)
 359 {
 360         rfcomm_dev_hold(dev);
 361         atomic_add(skb->truesize, &dev->wmem_alloc);
 362         skb->sk = (void *) dev;
 363         skb->destructor = rfcomm_wfree;
 364 }
 365
 366 static struct sk_buff *rfcomm_wmalloc(struct rfcomm_dev *dev, unsigned long size, gfp_t priority)
 367 {
 368         if (atomic_read(&dev->wmem_alloc) < rfcomm_room(dev->dlc)) {
 369                 struct sk_buff *skb = alloc_skb(size, priority);
 370                 if (skb) {
 371                         rfcomm_set_owner_w(skb, dev);
 372                         return skb;
 373                 }
 374         }
 375         return NULL;
 376 }
 377
 378 /* ---- Device IOCTLs ---- */
 379
 380 #define NOCAP_FLAGS ((1 << RFCOMM_REUSE_DLC) | (1 << RFCOMM_RELEASE_ONHUP))
 381
 382 static int rfcomm_create_dev(struct sock *sk, void __user *arg)
 383 {
 384         struct rfcomm_dev_req req;
 385         struct rfcomm_dlc *dlc;
 386         int id;
 387
 388         if (copy_from_user(&req, arg, sizeof(req)))
 389                 return -EFAULT;
 390
 391         BT_DBG("sk %p dev_id %d flags 0x%x", sk, req.dev_id, req.flags);
 392
 393         if (req.flags != NOCAP_FLAGS && !capable(CAP_NET_ADMIN))
 394                 return -EPERM;
 395
 396         if (req.flags & (1 << RFCOMM_REUSE_DLC)) {
 397                 /* Socket must be connected */
 398                 if (sk->sk_state != BT_CONNECTED)
 399                         return -EBADFD;
 400
 401                 dlc = rfcomm_pi(sk)->dlc;
 402                 rfcomm_dlc_hold(dlc);
 403         } else {
 404                 dlc = rfcomm_dlc_alloc(GFP_KERNEL);
 405                 if (!dlc)
 406                         return -ENOMEM;
 407         }
 408
 409         id = rfcomm_dev_add(&req, dlc);
 410         if (id < 0) {
 411                 rfcomm_dlc_put(dlc);
 412                 return id;
 413         }
 414
 415         if (req.flags & (1 << RFCOMM_REUSE_DLC)) {
 416                 /* DLC is now used by device.
 417                  * Socket must be disconnected */
 418                 sk->sk_state = BT_CLOSED;
 419         }
 420
 421         return id;
 422 }
 423
 424 static int rfcomm_release_dev(void __user *arg)
 425 {
 426         struct rfcomm_dev_req req;
 427         struct rfcomm_dev *dev;
 428
 429         if (copy_from_user(&req, arg, sizeof(req)))
 430                 return -EFAULT;
 431
 432         BT_DBG("dev_id %d flags 0x%x", req.dev_id, req.flags);
 433
 434         dev = rfcomm_dev_get(req.dev_id);
 435         if (!dev)
 436                 return -ENODEV;
 437
 438         if (dev->flags != NOCAP_FLAGS && !capable(CAP_NET_ADMIN)) {
 439                 rfcomm_dev_put(dev);
 440                 return -EPERM;
 441         }
 442
 443         if (req.flags & (1 << RFCOMM_HANGUP_NOW))
 444                 rfcomm_dlc_close(dev->dlc, 0);
 445
 446         /* Shut down TTY synchronously before freeing rfcomm_dev */
 447         if (dev->tty)
 448                 tty_vhangup(dev->tty);
 449
 450         if (!test_bit(RFCOMM_RELEASE_ONHUP, &dev->flags))
 451                 rfcomm_dev_del(dev);
 452         rfcomm_dev_put(dev);
 453         return 0;
 454 }
 455
 456 static int rfcomm_get_dev_list(void __user *arg)
 457 {
 458         struct rfcomm_dev_list_req *dl;
 459         struct rfcomm_dev_info *di;
 460         struct list_head *p;
 461         int n = 0, size, err;
 462         u16 dev_num;
 463
 464         BT_DBG("");
 465
 466         if (get_user(dev_num, (u16 __user *) arg))
 467                 return -EFAULT;
 468
 469         if (!dev_num || dev_num > (PAGE_SIZE * 4) / sizeof(*di))
 470                 return -EINVAL;
 471
 472         size = sizeof(*dl) + dev_num * sizeof(*di);
 473
 474         dl = kmalloc(size, GFP_KERNEL);
 475         if (!dl)
 476                 return -ENOMEM;
 477
 478         di = dl->dev_info;
 479
 480         read_lock_bh(&rfcomm_dev_lock);
 481
 482         list_for_each(p, &rfcomm_dev_list) {
 483                 struct rfcomm_dev *dev = list_entry(p, struct rfcomm_dev, list);
 484                 if (test_bit(RFCOMM_TTY_RELEASED, &dev->flags))
 485                         continue;
 486                 (di + n)->id      = dev->id;
 487                 (di + n)->flags   = dev->flags;
 488                 (di + n)->state   = dev->dlc->state;
 489                 (di + n)->channel = dev->channel;
 490                 bacpy(&(di + n)->src, &dev->src);
 491                 bacpy(&(di + n)->dst, &dev->dst);
 492                 if (++n >= dev_num)
 493                         break;
 494         }
 495
 496         read_unlock_bh(&rfcomm_dev_lock);
 497
 498         dl->dev_num = n;
 499         size = sizeof(*dl) + n * sizeof(*di);
 500
 501         err = copy_to_user(arg, dl, size);
 502         kfree(dl);
 503
 504         return err ? -EFAULT : 0;
 505 }
 506
 507 static int rfcomm_get_dev_info(void __user *arg)
 508 {
 509         struct rfcomm_dev *dev;
 510         struct rfcomm_dev_info di;
 511         int err = 0;
 512
 513         BT_DBG("");
 514
 515         if (copy_from_user(&di, arg, sizeof(di)))
 516                 return -EFAULT;
 517
 518         dev = rfcomm_dev_get(di.id);
 519         if (!dev)
 520                 return -ENODEV;
 521
 522         di.flags   = dev->flags;
 523         di.channel = dev->channel;
 524         di.state   = dev->dlc->state;
 525         bacpy(&di.src, &dev->src);
 526         bacpy(&di.dst, &dev->dst);
 527
 528         if (copy_to_user(arg, &di, sizeof(di)))
 529                 err = -EFAULT;
 530
 531         rfcomm_dev_put(dev);
 532         return err;
 533 }
 534
 535 int rfcomm_dev_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
 536 {
 537         BT_DBG("cmd %d arg %p", cmd, arg);
 538
 539         switch (cmd) {
 540         case RFCOMMCREATEDEV:
 541                 return rfcomm_create_dev(sk, arg);
 542
 543         case RFCOMMRELEASEDEV:
 544                 return rfcomm_release_dev(arg);
 545
 546         case RFCOMMGETDEVLIST:
 547                 return rfcomm_get_dev_list(arg);
 548
 549         case RFCOMMGETDEVINFO:
 550                 return rfcomm_get_dev_info(arg);
 551         }
 552
 553         return -EINVAL;
 554 }
 555
 556 /* ---- DLC callbacks ---- */
 557 static void rfcomm_dev_data_ready(struct rfcomm_dlc *dlc, struct sk_buff *skb)
 558 {
 559         struct rfcomm_dev *dev = dlc->owner;
 560         struct tty_struct *tty;
 561
 562         if (!dev) {
 563                 kfree_skb(skb);
 564                 return;
 565         }
 566
 567         tty = dev->tty;
 568         if (!tty || !skb_queue_empty(&dev->pending)) {
 569                 skb_queue_tail(&dev->pending, skb);
 570                 return;
 571         }
 572
 573         BT_DBG("dlc %p tty %p len %d", dlc, tty, skb->len);
 574
 575         tty_insert_flip_string(tty, skb->data, skb->len);
 576         tty_flip_buffer_push(tty);
 577
 578         kfree_skb(skb);
 579 }
 580
 581 static void rfcomm_dev_state_change(struct rfcomm_dlc *dlc, int err)
 582 {
 583         struct rfcomm_dev *dev = dlc->owner;
 584         if (!dev)
 585                 return;
 586
 587         BT_DBG("dlc %p dev %p err %d", dlc, dev, err);
 588
 589         dev->err = err;
 590         wake_up_interruptible(&dev->wait);
 591
 592         if (dlc->state == BT_CLOSED) {
 593                 if (!dev->tty) {
 594                         if (test_bit(RFCOMM_RELEASE_ONHUP, &dev->flags)) {
 595                                 /* Drop DLC lock here to avoid deadlock
 596                                  * 1. rfcomm_dev_get will take rfcomm_dev_lock
 597                                  *    but in rfcomm_dev_add there's lock order:
 598                                  *    rfcomm_dev_lock -> dlc lock
 599                                  * 2. rfcomm_dev_put will deadlock if it's
 600                                  *    the last reference
 601                                  */
 602                                 rfcomm_dlc_unlock(dlc);
 603                                 if (rfcomm_dev_get(dev->id) == NULL) {
 604                                         rfcomm_dlc_lock(dlc);
 605                                         return;
 606                                 }
 607
 608                                 rfcomm_dev_del(dev);
 609                                 rfcomm_dev_put(dev);
 610                                 rfcomm_dlc_lock(dlc);
 611                         }
 612                 } else
 613                         tty_hangup(dev->tty);
 614         }
 615 }
 616
 617 static void rfcomm_dev_modem_status(struct rfcomm_dlc *dlc, u8 v24_sig)
 618 {
 619         struct rfcomm_dev *dev = dlc->owner;
 620         if (!dev)
 621                 return;
 622
 623         BT_DBG("dlc %p dev %p v24_sig 0x%02x", dlc, dev, v24_sig);
 624
 625         if ((dev->modem_status & TIOCM_CD) && !(v24_sig & RFCOMM_V24_DV)) {
 626                 if (dev->tty && !C_CLOCAL(dev->tty))
 627                         tty_hangup(dev->tty);
 628         }
 629
 630         dev->modem_status =
 631                 ((v24_sig & RFCOMM_V24_RTC) ? (TIOCM_DSR | TIOCM_DTR) : 0) |
 632                 ((v24_sig & RFCOMM_V24_RTR) ? (TIOCM_RTS | TIOCM_CTS) : 0) |
 633                 ((v24_sig & RFCOMM_V24_IC)  ? TIOCM_RI : 0) |
 634                 ((v24_sig & RFCOMM_V24_DV)  ? TIOCM_CD : 0);
 635 }
 636
 637 /* ---- TTY functions ---- */
 638 static void rfcomm_tty_wakeup(unsigned long arg)
 639 {
 640         struct rfcomm_dev *dev = (void *) arg;
 641         struct tty_struct *tty = dev->tty;
 642         if (!tty)
 643                 return;
 644
 645         BT_DBG("dev %p tty %p", dev, tty);
 646         tty_wakeup(tty);
 647 }
 648
 649 static void rfcomm_tty_copy_pending(struct rfcomm_dev *dev)
 650 {
 651         struct tty_struct *tty = dev->tty;
 652         struct sk_buff *skb;
 653         int inserted = 0;
 654
 655         if (!tty)
 656                 return;
 657
 658         BT_DBG("dev %p tty %p", dev, tty);
 659
 660         rfcomm_dlc_lock(dev->dlc);
 661
 662         while ((skb = skb_dequeue(&dev->pending))) {
 663                 inserted += tty_insert_flip_string(tty, skb->data, skb->len);
 664                 kfree_skb(skb);
 665         }
 666
 667         rfcomm_dlc_unlock(dev->dlc);
 668
 669         if (inserted > 0)
 670                 tty_flip_buffer_push(tty);
 671 }
 672
 673 static int rfcomm_tty_open(struct tty_struct *tty, struct file *filp)
 674 {
 675         DECLARE_WAITQUEUE(wait, current);
 676         struct rfcomm_dev *dev;
 677         struct rfcomm_dlc *dlc;
 678         int err, id;
 679
 680         id = tty->index;
 681
 682         BT_DBG("tty %p id %d", tty, id);
 683
 684         /* We don't leak this refcount. For reasons which are not entirely
 685            clear, the TTY layer will call our ->close() method even if the
 686            open fails. We decrease the refcount there, and decreasing it
 687            here too would cause breakage. */
 688         dev = rfcomm_dev_get(id);
 689         if (!dev)
 690                 return -ENODEV;
 691
 692         BT_DBG("dev %p dst %s channel %d opened %d", dev, batostr(&dev->dst),
 693                                 dev->channel, atomic_read(&dev->opened));
 694
 695         if (atomic_inc_return(&dev->opened) > 1)
 696                 return 0;
 697
 698         dlc = dev->dlc;
 699
 700         /* Attach TTY and open DLC */
 701
 702         rfcomm_dlc_lock(dlc);
 703         tty->driver_data = dev;
 704         dev->tty = tty;
 705         rfcomm_dlc_unlock(dlc);
 706         set_bit(RFCOMM_TTY_ATTACHED, &dev->flags);
 707
 708         err = rfcomm_dlc_open(dlc, &dev->src, &dev->dst, dev->channel);
 709         if (err < 0)
 710                 return err;
 711
 712         /* Wait for DLC to connect */
 713         add_wait_queue(&dev->wait, &wait);
 714         while (1) {
 715                 set_current_state(TASK_INTERRUPTIBLE);
 716
 717                 if (dlc->state == BT_CLOSED) {
 718                         err = -dev->err;
 719                         break;
 720                 }
 721
 722                 if (dlc->state == BT_CONNECTED)
 723                         break;
 724
 725                 if (signal_pending(current)) {
 726                         err = -EINTR;
 727                         break;
 728                 }
 729
 730                 schedule();
 731         }
 732         set_current_state(TASK_RUNNING);
 733         remove_wait_queue(&dev->wait, &wait);
 734
 735         if (err == 0)
 736                 device_move(dev->tty_dev, rfcomm_get_device(dev),
 737                             DPM_ORDER_DEV_AFTER_PARENT);
 738
 739         rfcomm_tty_copy_pending(dev);
 740
 741         rfcomm_dlc_unthrottle(dev->dlc);
 742
 743         return err;
 744 }
 745
 746 static void rfcomm_tty_close(struct tty_struct *tty, struct file *filp)
 747 {
 748         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
 749         if (!dev)
 750                 return;
 751
 752         BT_DBG("tty %p dev %p dlc %p opened %d", tty, dev, dev->dlc,
 753                                                 atomic_read(&dev->opened));
 754
 755         if (atomic_dec_and_test(&dev->opened)) {
 756                 if (dev->tty_dev->parent)
 757                         device_move(dev->tty_dev, NULL, DPM_ORDER_DEV_LAST);
 758
 759                 /* Close DLC and dettach TTY */
 760                 rfcomm_dlc_close(dev->dlc, 0);
 761
 762                 clear_bit(RFCOMM_TTY_ATTACHED, &dev->flags);
 763                 tasklet_kill(&dev->wakeup_task);
 764
 765                 rfcomm_dlc_lock(dev->dlc);
 766                 tty->driver_data = NULL;
 767                 dev->tty = NULL;
 768                 rfcomm_dlc_unlock(dev->dlc);
 769
 770                 if (test_bit(RFCOMM_TTY_RELEASED, &dev->flags)) {
 771                         write_lock_bh(&rfcomm_dev_lock);
 772                         list_del_init(&dev->list);
 773                         write_unlock_bh(&rfcomm_dev_lock);
 774
 775                         rfcomm_dev_put(dev);
 776                 }
 777         }
 778
 779         rfcomm_dev_put(dev);
 780 }
 781
 782 static int rfcomm_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
 783 {
 784         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
 785         struct rfcomm_dlc *dlc = dev->dlc;
 786         struct sk_buff *skb;
 787         int err = 0, sent = 0, size;
 788
 789         BT_DBG("tty %p count %d", tty, count);
 790
 791         while (count) {
 792                 size = min_t(uint, count, dlc->mtu);
 793
 794                 skb = rfcomm_wmalloc(dev, size + RFCOMM_SKB_RESERVE, GFP_ATOMIC);
 795
 796                 if (!skb)
 797                         break;
 798
 799                 skb_reserve(skb, RFCOMM_SKB_HEAD_RESERVE);
 800
 801                 memcpy(skb_put(skb, size), buf + sent, size);
 802
 803                 err = rfcomm_dlc_send(dlc, skb);
 804                 if (err < 0) {
 805                         kfree_skb(skb);
 806                         break;
 807                 }
 808
 809                 sent  += size;
 810                 count -= size;
 811         }
 812
 813         return sent ? sent : err;
 814 }
 815
 816 static int rfcomm_tty_write_room(struct tty_struct *tty)
 817 {
 818         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
 819         int room;
 820
 821         BT_DBG("tty %p", tty);
 822
 823         if (!dev || !dev->dlc)
 824                 return 0;
 825
 826         room = rfcomm_room(dev->dlc) - atomic_read(&dev->wmem_alloc);
 827         if (room < 0)
 828                 room = 0;
 829
 830         return room;
 831 }
 832
 833 static int rfcomm_tty_ioctl(struct tty_struct *tty, struct file *filp, unsigned int cmd, unsigned long arg)
 834 {
 835         BT_DBG("tty %p cmd 0x%02x", tty, cmd);
 836
 837         switch (cmd) {
 838         case TCGETS:
 839                 BT_DBG("TCGETS is not supported");
 840                 return -ENOIOCTLCMD;
 841
 842         case TCSETS:
 843                 BT_DBG("TCSETS is not supported");
 844                 return -ENOIOCTLCMD;
 845
 846         case TIOCMIWAIT:
 847                 BT_DBG("TIOCMIWAIT");
 848                 break;
 849
 850         case TIOCGSERIAL:
 851                 BT_ERR("TIOCGSERIAL is not supported");
 852                 return -ENOIOCTLCMD;
 853
 854         case TIOCSSERIAL:
 855                 BT_ERR("TIOCSSERIAL is not supported");
 856                 return -ENOIOCTLCMD;
 857
 858         case TIOCSERGSTRUCT:
 859                 BT_ERR("TIOCSERGSTRUCT is not supported");
 860                 return -ENOIOCTLCMD;
 861
 862         case TIOCSERGETLSR:
 863                 BT_ERR("TIOCSERGETLSR is not supported");
 864                 return -ENOIOCTLCMD;
 865
 866         case TIOCSERCONFIG:
 867                 BT_ERR("TIOCSERCONFIG is not supported");
 868                 return -ENOIOCTLCMD;
 869
 870         default:
 871                 return -ENOIOCTLCMD;    /* ioctls which we must ignore */
 872
 873         }
 874
 875         return -ENOIOCTLCMD;
 876 }
 877
 878 static void rfcomm_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
 879 {
 880         struct ktermios *new = tty->termios;
 881         int old_baud_rate = tty_termios_baud_rate(old);
 882         int new_baud_rate = tty_termios_baud_rate(new);
 883
 884         u8 baud, data_bits, stop_bits, parity, x_on, x_off;
 885         u16 changes = 0;
 886
 887         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
 888
 889         BT_DBG("tty %p termios %p", tty, old);
 890
 891         if (!dev || !dev->dlc || !dev->dlc->session)
 892                 return;
 893
 894         /* Handle turning off CRTSCTS */
 895         if ((old->c_cflag & CRTSCTS) && !(new->c_cflag & CRTSCTS))
 896                 BT_DBG("Turning off CRTSCTS unsupported");
 897
 898         /* Parity on/off and when on, odd/even */
 899         if (((old->c_cflag & PARENB) != (new->c_cflag & PARENB)) ||
 900                         ((old->c_cflag & PARODD) != (new->c_cflag & PARODD))) {
 901                 changes |= RFCOMM_RPN_PM_PARITY;
 902                 BT_DBG("Parity change detected.");
 903         }
 904
 905         /* Mark and space parity are not supported! */
 906         if (new->c_cflag & PARENB) {
 907                 if (new->c_cflag & PARODD) {
 908                         BT_DBG("Parity is ODD");
 909                         parity = RFCOMM_RPN_PARITY_ODD;
 910                 } else {
 911                         BT_DBG("Parity is EVEN");
 912                         parity = RFCOMM_RPN_PARITY_EVEN;
 913                 }
 914         } else {
 915                 BT_DBG("Parity is OFF");
 916                 parity = RFCOMM_RPN_PARITY_NONE;
 917         }
 918
 919         /* Setting the x_on / x_off characters */
 920         if (old->c_cc[VSTOP] != new->c_cc[VSTOP]) {
 921                 BT_DBG("XOFF custom");
 922                 x_on = new->c_cc[VSTOP];
 923                 changes |= RFCOMM_RPN_PM_XON;
 924         } else {
 925                 BT_DBG("XOFF default");
 926                 x_on = RFCOMM_RPN_XON_CHAR;
 927         }
 928
 929         if (old->c_cc[VSTART] != new->c_cc[VSTART]) {
 930                 BT_DBG("XON custom");
 931                 x_off = new->c_cc[VSTART];
 932                 changes |= RFCOMM_RPN_PM_XOFF;
 933         } else {
 934                 BT_DBG("XON default");
 935                 x_off = RFCOMM_RPN_XOFF_CHAR;
 936         }
 937
 938         /* Handle setting of stop bits */
 939         if ((old->c_cflag & CSTOPB) != (new->c_cflag & CSTOPB))
 940                 changes |= RFCOMM_RPN_PM_STOP;
 941
 942         /* POSIX does not support 1.5 stop bits and RFCOMM does not
 943          * support 2 stop bits. So a request for 2 stop bits gets
 944          * translated to 1.5 stop bits */
 945         if (new->c_cflag & CSTOPB)
 946                 stop_bits = RFCOMM_RPN_STOP_15;
 947         else
 948                 stop_bits = RFCOMM_RPN_STOP_1;
 949
 950         /* Handle number of data bits [5-8] */
 951         if ((old->c_cflag & CSIZE) != (new->c_cflag & CSIZE))
 952                 changes |= RFCOMM_RPN_PM_DATA;
 953
 954         switch (new->c_cflag & CSIZE) {
 955         case CS5:
 956                 data_bits = RFCOMM_RPN_DATA_5;
 957                 break;
 958         case CS6:
 959                 data_bits = RFCOMM_RPN_DATA_6;
 960                 break;
 961         case CS7:
 962                 data_bits = RFCOMM_RPN_DATA_7;
 963                 break;
 964         case CS8:
 965                 data_bits = RFCOMM_RPN_DATA_8;
 966                 break;
 967         default:
 968                 data_bits = RFCOMM_RPN_DATA_8;
 969                 break;
 970         }
 971
 972         /* Handle baudrate settings */
 973         if (old_baud_rate != new_baud_rate)
 974                 changes |= RFCOMM_RPN_PM_BITRATE;
 975
 976         switch (new_baud_rate) {
 977         case 2400:
 978                 baud = RFCOMM_RPN_BR_2400;
 979                 break;
 980         case 4800:
 981                 baud = RFCOMM_RPN_BR_4800;
 982                 break;
 983         case 7200:
 984                 baud = RFCOMM_RPN_BR_7200;
 985                 break;
 986         case 9600:
 987                 baud = RFCOMM_RPN_BR_9600;
 988                 break;
 989         case 19200:
 990                 baud = RFCOMM_RPN_BR_19200;
 991                 break;
 992         case 38400:
 993                 baud = RFCOMM_RPN_BR_38400;
 994                 break;
 995         case 57600:
 996                 baud = RFCOMM_RPN_BR_57600;
 997                 break;
 998         case 115200:
 999                 baud = RFCOMM_RPN_BR_115200;
1000                 break;
1001         case 230400:
1002                 baud = RFCOMM_RPN_BR_230400;
1003                 break;
1004         default:
1005                 /* 9600 is standard accordinag to the RFCOMM specification */
1006                 baud = RFCOMM_RPN_BR_9600;
1007                 break;
1008
1009         }
1010
1011         if (changes)
1012                 rfcomm_send_rpn(dev->dlc->session, 1, dev->dlc->dlci, baud,
1013                                 data_bits, stop_bits, parity,
1014                                 RFCOMM_RPN_FLOW_NONE, x_on, x_off, changes);
1015 }
1016
1017 static void rfcomm_tty_throttle(struct tty_struct *tty)
1018 {
1019         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
1020
1021         BT_DBG("tty %p dev %p", tty, dev);
1022
1023         rfcomm_dlc_throttle(dev->dlc);
1024 }
1025
1026 static void rfcomm_tty_unthrottle(struct tty_struct *tty)
1027 {
1028         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
1029
1030         BT_DBG("tty %p dev %p", tty, dev);
1031
1032         rfcomm_dlc_unthrottle(dev->dlc);
1033 }
1034
1035 static int rfcomm_tty_chars_in_buffer(struct tty_struct *tty)
1036 {
1037         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
1038
1039         BT_DBG("tty %p dev %p", tty, dev);
1040
1041         if (!dev || !dev->dlc)
1042                 return 0;
1043
1044         if (!skb_queue_empty(&dev->dlc->tx_queue))
1045                 return dev->dlc->mtu;
1046
1047         return 0;
1048 }
1049
1050 static void rfcomm_tty_flush_buffer(struct tty_struct *tty)
1051 {
1052         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
1053
1054         BT_DBG("tty %p dev %p", tty, dev);
1055
1056         if (!dev || !dev->dlc)
1057                 return;
1058
1059         skb_queue_purge(&dev->dlc->tx_queue);
1060         tty_wakeup(tty);
1061 }
1062
1063 static void rfcomm_tty_send_xchar(struct tty_struct *tty, char ch)
1064 {
1065         BT_DBG("tty %p ch %c", tty, ch);
1066 }
1067
1068 static void rfcomm_tty_wait_until_sent(struct tty_struct *tty, int timeout)
1069 {
1070         BT_DBG("tty %p timeout %d", tty, timeout);
1071 }
1072
1073 static void rfcomm_tty_hangup(struct tty_struct *tty)
1074 {
1075         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
1076
1077         BT_DBG("tty %p dev %p", tty, dev);
1078
1079         if (!dev)
1080                 return;
1081
1082         rfcomm_tty_flush_buffer(tty);
1083
1084         if (test_bit(RFCOMM_RELEASE_ONHUP, &dev->flags)) {
1085                 if (rfcomm_dev_get(dev->id) == NULL)
1086                         return;
1087                 rfcomm_dev_del(dev);
1088                 rfcomm_dev_put(dev);
1089         }
1090 }
1091
1092 static int rfcomm_tty_tiocmget(struct tty_struct *tty)
1093 {
1094         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
1095
1096         BT_DBG("tty %p dev %p", tty, dev);
1097
1098         return dev->modem_status;
1099 }
1100
1101 static int rfcomm_tty_tiocmset(struct tty_struct *tty, struct file *filp, unsigned int set, unsigned int clear)
1102 {
1103         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
1104         struct rfcomm_dlc *dlc = dev->dlc;
1105         u8 v24_sig;
1106
1107         BT_DBG("tty %p dev %p set 0x%02x clear 0x%02x", tty, dev, set, clear);
1108
1109         rfcomm_dlc_get_modem_status(dlc, &v24_sig);
1110
1111         if (set & TIOCM_DSR || set & TIOCM_DTR)
1112                 v24_sig |= RFCOMM_V24_RTC;
1113         if (set & TIOCM_RTS || set & TIOCM_CTS)
1114                 v24_sig |= RFCOMM_V24_RTR;
1115         if (set & TIOCM_RI)
1116                 v24_sig |= RFCOMM_V24_IC;
1117         if (set & TIOCM_CD)
1118                 v24_sig |= RFCOMM_V24_DV;
1119
1120         if (clear & TIOCM_DSR || clear & TIOCM_DTR)
1121                 v24_sig &= ~RFCOMM_V24_RTC;
1122         if (clear & TIOCM_RTS || clear & TIOCM_CTS)
1123                 v24_sig &= ~RFCOMM_V24_RTR;
1124         if (clear & TIOCM_RI)
1125                 v24_sig &= ~RFCOMM_V24_IC;
1126         if (clear & TIOCM_CD)
1127                 v24_sig &= ~RFCOMM_V24_DV;
1128
1129         rfcomm_dlc_set_modem_status(dlc, v24_sig);
1130
1131         return 0;
1132 }
1133
1134 /* ---- TTY structure ---- */
1135
1136 static const struct tty_operations rfcomm_ops = {
1137         .open                   = rfcomm_tty_open,
1138         .close                  = rfcomm_tty_close,
1139         .write                  = rfcomm_tty_write,
1140         .write_room             = rfcomm_tty_write_room,
1141         .chars_in_buffer        = rfcomm_tty_chars_in_buffer,
1142         .flush_buffer           = rfcomm_tty_flush_buffer,
1143         .ioctl                  = rfcomm_tty_ioctl,
1144         .throttle               = rfcomm_tty_throttle,
1145         .unthrottle             = rfcomm_tty_unthrottle,
1146         .set_termios            = rfcomm_tty_set_termios,
1147         .send_xchar             = rfcomm_tty_send_xchar,
1148         .hangup                 = rfcomm_tty_hangup,
1149         .wait_until_sent        = rfcomm_tty_wait_until_sent,
1150         .tiocmget               = rfcomm_tty_tiocmget,
1151         .tiocmset               = rfcomm_tty_tiocmset,
1152 };
1153
1154 int __init rfcomm_init_ttys(void)
1155 {
1156         rfcomm_tty_driver = alloc_tty_driver(RFCOMM_TTY_PORTS);
1157         if (!rfcomm_tty_driver)
1158                 return -1;
1159
1160         rfcomm_tty_driver->owner        = THIS_MODULE;
1161         rfcomm_tty_driver->driver_name  = "rfcomm";
1162         rfcomm_tty_driver->name         = "rfcomm";
1163         rfcomm_tty_driver->major        = RFCOMM_TTY_MAJOR;
1164         rfcomm_tty_driver->minor_start  = RFCOMM_TTY_MINOR;
1165         rfcomm_tty_driver->type         = TTY_DRIVER_TYPE_SERIAL;
1166         rfcomm_tty_driver->subtype      = SERIAL_TYPE_NORMAL;
1167         rfcomm_tty_driver->flags        = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
1168         rfcomm_tty_driver->init_termios = tty_std_termios;
1169         rfcomm_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
1170         rfcomm_tty_driver->init_termios.c_lflag &= ~ICANON;
1171         tty_set_operations(rfcomm_tty_driver, &rfcomm_ops);
1172
1173         if (tty_register_driver(rfcomm_tty_driver)) {
1174                 BT_ERR("Can't register RFCOMM TTY driver");
1175                 put_tty_driver(rfcomm_tty_driver);
1176                 return -1;
1177         }
1178
1179         BT_INFO("RFCOMM TTY layer initialized");
1180
1181         return 0;
1182 }
1183
1184 void rfcomm_cleanup_ttys(void)
1185 {
1186         tty_unregister_driver(rfcomm_tty_driver);
1187         put_tty_driver(rfcomm_tty_driver);
1188 }