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         if (!(dev = rfcomm_dev_get(req.dev_id)))
 435                 return -ENODEV;
 436
 437         if (dev->flags != NOCAP_FLAGS && !capable(CAP_NET_ADMIN)) {
 438                 rfcomm_dev_put(dev);
 439                 return -EPERM;
 440         }
 441
 442         if (req.flags & (1 << RFCOMM_HANGUP_NOW))
 443                 rfcomm_dlc_close(dev->dlc, 0);
 444
 445         /* Shut down TTY synchronously before freeing rfcomm_dev */
 446         if (dev->tty)
 447                 tty_vhangup(dev->tty);
 448
 449         if (!test_bit(RFCOMM_RELEASE_ONHUP, &dev->flags))
 450                 rfcomm_dev_del(dev);
 451         rfcomm_dev_put(dev);
 452         return 0;
 453 }
 454
 455 static int rfcomm_get_dev_list(void __user *arg)
 456 {
 457         struct rfcomm_dev_list_req *dl;
 458         struct rfcomm_dev_info *di;
 459         struct list_head *p;
 460         int n = 0, size, err;
 461         u16 dev_num;
 462
 463         BT_DBG("");
 464
 465         if (get_user(dev_num, (u16 __user *) arg))
 466                 return -EFAULT;
 467
 468         if (!dev_num || dev_num > (PAGE_SIZE * 4) / sizeof(*di))
 469                 return -EINVAL;
 470
 471         size = sizeof(*dl) + dev_num * sizeof(*di);
 472
 473         if (!(dl = kmalloc(size, GFP_KERNEL)))
 474                 return -ENOMEM;
 475
 476         di = dl->dev_info;
 477
 478         read_lock_bh(&rfcomm_dev_lock);
 479
 480         list_for_each(p, &rfcomm_dev_list) {
 481                 struct rfcomm_dev *dev = list_entry(p, struct rfcomm_dev, list);
 482                 if (test_bit(RFCOMM_TTY_RELEASED, &dev->flags))
 483                         continue;
 484                 (di + n)->id      = dev->id;
 485                 (di + n)->flags   = dev->flags;
 486                 (di + n)->state   = dev->dlc->state;
 487                 (di + n)->channel = dev->channel;
 488                 bacpy(&(di + n)->src, &dev->src);
 489                 bacpy(&(di + n)->dst, &dev->dst);
 490                 if (++n >= dev_num)
 491                         break;
 492         }
 493
 494         read_unlock_bh(&rfcomm_dev_lock);
 495
 496         dl->dev_num = n;
 497         size = sizeof(*dl) + n * sizeof(*di);
 498
 499         err = copy_to_user(arg, dl, size);
 500         kfree(dl);
 501
 502         return err ? -EFAULT : 0;
 503 }
 504
 505 static int rfcomm_get_dev_info(void __user *arg)
 506 {
 507         struct rfcomm_dev *dev;
 508         struct rfcomm_dev_info di;
 509         int err = 0;
 510
 511         BT_DBG("");
 512
 513         if (copy_from_user(&di, arg, sizeof(di)))
 514                 return -EFAULT;
 515
 516         if (!(dev = rfcomm_dev_get(di.id)))
 517                 return -ENODEV;
 518
 519         di.flags   = dev->flags;
 520         di.channel = dev->channel;
 521         di.state   = dev->dlc->state;
 522         bacpy(&di.src, &dev->src);
 523         bacpy(&di.dst, &dev->dst);
 524
 525         if (copy_to_user(arg, &di, sizeof(di)))
 526                 err = -EFAULT;
 527
 528         rfcomm_dev_put(dev);
 529         return err;
 530 }
 531
 532 int rfcomm_dev_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
 533 {
 534         BT_DBG("cmd %d arg %p", cmd, arg);
 535
 536         switch (cmd) {
 537         case RFCOMMCREATEDEV:
 538                 return rfcomm_create_dev(sk, arg);
 539
 540         case RFCOMMRELEASEDEV:
 541                 return rfcomm_release_dev(arg);
 542
 543         case RFCOMMGETDEVLIST:
 544                 return rfcomm_get_dev_list(arg);
 545
 546         case RFCOMMGETDEVINFO:
 547                 return rfcomm_get_dev_info(arg);
 548         }
 549
 550         return -EINVAL;
 551 }
 552
 553 /* ---- DLC callbacks ---- */
 554 static void rfcomm_dev_data_ready(struct rfcomm_dlc *dlc, struct sk_buff *skb)
 555 {
 556         struct rfcomm_dev *dev = dlc->owner;
 557         struct tty_struct *tty;
 558
 559         if (!dev) {
 560                 kfree_skb(skb);
 561                 return;
 562         }
 563
 564         if (!(tty = dev->tty) || !skb_queue_empty(&dev->pending)) {
 565                 skb_queue_tail(&dev->pending, skb);
 566                 return;
 567         }
 568
 569         BT_DBG("dlc %p tty %p len %d", dlc, tty, skb->len);
 570
 571         tty_insert_flip_string(tty, skb->data, skb->len);
 572         tty_flip_buffer_push(tty);
 573
 574         kfree_skb(skb);
 575 }
 576
 577 static void rfcomm_dev_state_change(struct rfcomm_dlc *dlc, int err)
 578 {
 579         struct rfcomm_dev *dev = dlc->owner;
 580         if (!dev)
 581                 return;
 582
 583         BT_DBG("dlc %p dev %p err %d", dlc, dev, err);
 584
 585         dev->err = err;
 586         wake_up_interruptible(&dev->wait);
 587
 588         if (dlc->state == BT_CLOSED) {
 589                 if (!dev->tty) {
 590                         if (test_bit(RFCOMM_RELEASE_ONHUP, &dev->flags)) {
 591                                 /* Drop DLC lock here to avoid deadlock
 592                                  * 1. rfcomm_dev_get will take rfcomm_dev_lock
 593                                  *    but in rfcomm_dev_add there's lock order:
 594                                  *    rfcomm_dev_lock -> dlc lock
 595                                  * 2. rfcomm_dev_put will deadlock if it's
 596                                  *    the last reference
 597                                  */
 598                                 rfcomm_dlc_unlock(dlc);
 599                                 if (rfcomm_dev_get(dev->id) == NULL) {
 600                                         rfcomm_dlc_lock(dlc);
 601                                         return;
 602                                 }
 603
 604                                 rfcomm_dev_del(dev);
 605                                 rfcomm_dev_put(dev);
 606                                 rfcomm_dlc_lock(dlc);
 607                         }
 608                 } else
 609                         tty_hangup(dev->tty);
 610         }
 611 }
 612
 613 static void rfcomm_dev_modem_status(struct rfcomm_dlc *dlc, u8 v24_sig)
 614 {
 615         struct rfcomm_dev *dev = dlc->owner;
 616         if (!dev)
 617                 return;
 618
 619         BT_DBG("dlc %p dev %p v24_sig 0x%02x", dlc, dev, v24_sig);
 620
 621         if ((dev->modem_status & TIOCM_CD) && !(v24_sig & RFCOMM_V24_DV)) {
 622                 if (dev->tty && !C_CLOCAL(dev->tty))
 623                         tty_hangup(dev->tty);
 624         }
 625
 626         dev->modem_status =
 627                 ((v24_sig & RFCOMM_V24_RTC) ? (TIOCM_DSR | TIOCM_DTR) : 0) |
 628                 ((v24_sig & RFCOMM_V24_RTR) ? (TIOCM_RTS | TIOCM_CTS) : 0) |
 629                 ((v24_sig & RFCOMM_V24_IC)  ? TIOCM_RI : 0) |
 630                 ((v24_sig & RFCOMM_V24_DV)  ? TIOCM_CD : 0);
 631 }
 632
 633 /* ---- TTY functions ---- */
 634 static void rfcomm_tty_wakeup(unsigned long arg)
 635 {
 636         struct rfcomm_dev *dev = (void *) arg;
 637         struct tty_struct *tty = dev->tty;
 638         if (!tty)
 639                 return;
 640
 641         BT_DBG("dev %p tty %p", dev, tty);
 642         tty_wakeup(tty);
 643 }
 644
 645 static void rfcomm_tty_copy_pending(struct rfcomm_dev *dev)
 646 {
 647         struct tty_struct *tty = dev->tty;
 648         struct sk_buff *skb;
 649         int inserted = 0;
 650
 651         if (!tty)
 652                 return;
 653
 654         BT_DBG("dev %p tty %p", dev, tty);
 655
 656         rfcomm_dlc_lock(dev->dlc);
 657
 658         while ((skb = skb_dequeue(&dev->pending))) {
 659                 inserted += tty_insert_flip_string(tty, skb->data, skb->len);
 660                 kfree_skb(skb);
 661         }
 662
 663         rfcomm_dlc_unlock(dev->dlc);
 664
 665         if (inserted > 0)
 666                 tty_flip_buffer_push(tty);
 667 }
 668
 669 static int rfcomm_tty_open(struct tty_struct *tty, struct file *filp)
 670 {
 671         DECLARE_WAITQUEUE(wait, current);
 672         struct rfcomm_dev *dev;
 673         struct rfcomm_dlc *dlc;
 674         int err, id;
 675
 676         id = tty->index;
 677
 678         BT_DBG("tty %p id %d", tty, id);
 679
 680         /* We don't leak this refcount. For reasons which are not entirely
 681            clear, the TTY layer will call our ->close() method even if the
 682            open fails. We decrease the refcount there, and decreasing it
 683            here too would cause breakage. */
 684         dev = rfcomm_dev_get(id);
 685         if (!dev)
 686                 return -ENODEV;
 687
 688         BT_DBG("dev %p dst %s channel %d opened %d", dev, batostr(&dev->dst),
 689                                 dev->channel, atomic_read(&dev->opened));
 690
 691         if (atomic_inc_return(&dev->opened) > 1)
 692                 return 0;
 693
 694         dlc = dev->dlc;
 695
 696         /* Attach TTY and open DLC */
 697
 698         rfcomm_dlc_lock(dlc);
 699         tty->driver_data = dev;
 700         dev->tty = tty;
 701         rfcomm_dlc_unlock(dlc);
 702         set_bit(RFCOMM_TTY_ATTACHED, &dev->flags);
 703
 704         err = rfcomm_dlc_open(dlc, &dev->src, &dev->dst, dev->channel);
 705         if (err < 0)
 706                 return err;
 707
 708         /* Wait for DLC to connect */
 709         add_wait_queue(&dev->wait, &wait);
 710         while (1) {
 711                 set_current_state(TASK_INTERRUPTIBLE);
 712
 713                 if (dlc->state == BT_CLOSED) {
 714                         err = -dev->err;
 715                         break;
 716                 }
 717
 718                 if (dlc->state == BT_CONNECTED)
 719                         break;
 720
 721                 if (signal_pending(current)) {
 722                         err = -EINTR;
 723                         break;
 724                 }
 725
 726                 schedule();
 727         }
 728         set_current_state(TASK_RUNNING);
 729         remove_wait_queue(&dev->wait, &wait);
 730
 731         if (err == 0)
 732                 device_move(dev->tty_dev, rfcomm_get_device(dev),
 733                             DPM_ORDER_DEV_AFTER_PARENT);
 734
 735         rfcomm_tty_copy_pending(dev);
 736
 737         rfcomm_dlc_unthrottle(dev->dlc);
 738
 739         return err;
 740 }
 741
 742 static void rfcomm_tty_close(struct tty_struct *tty, struct file *filp)
 743 {
 744         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
 745         if (!dev)
 746                 return;
 747
 748         BT_DBG("tty %p dev %p dlc %p opened %d", tty, dev, dev->dlc,
 749                                                 atomic_read(&dev->opened));
 750
 751         if (atomic_dec_and_test(&dev->opened)) {
 752                 if (dev->tty_dev->parent)
 753                         device_move(dev->tty_dev, NULL, DPM_ORDER_DEV_LAST);
 754
 755                 /* Close DLC and dettach TTY */
 756                 rfcomm_dlc_close(dev->dlc, 0);
 757
 758                 clear_bit(RFCOMM_TTY_ATTACHED, &dev->flags);
 759                 tasklet_kill(&dev->wakeup_task);
 760
 761                 rfcomm_dlc_lock(dev->dlc);
 762                 tty->driver_data = NULL;
 763                 dev->tty = NULL;
 764                 rfcomm_dlc_unlock(dev->dlc);
 765
 766                 if (test_bit(RFCOMM_TTY_RELEASED, &dev->flags)) {
 767                         write_lock_bh(&rfcomm_dev_lock);
 768                         list_del_init(&dev->list);
 769                         write_unlock_bh(&rfcomm_dev_lock);
 770
 771                         rfcomm_dev_put(dev);
 772                 }
 773         }
 774
 775         rfcomm_dev_put(dev);
 776 }
 777
 778 static int rfcomm_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
 779 {
 780         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
 781         struct rfcomm_dlc *dlc = dev->dlc;
 782         struct sk_buff *skb;
 783         int err = 0, sent = 0, size;
 784
 785         BT_DBG("tty %p count %d", tty, count);
 786
 787         while (count) {
 788                 size = min_t(uint, count, dlc->mtu);
 789
 790                 skb = rfcomm_wmalloc(dev, size + RFCOMM_SKB_RESERVE, GFP_ATOMIC);
 791
 792                 if (!skb)
 793                         break;
 794
 795                 skb_reserve(skb, RFCOMM_SKB_HEAD_RESERVE);
 796
 797                 memcpy(skb_put(skb, size), buf + sent, size);
 798
 799                 if ((err = rfcomm_dlc_send(dlc, skb)) < 0) {
 800                         kfree_skb(skb);
 801                         break;
 802                 }
 803
 804                 sent  += size;
 805                 count -= size;
 806         }
 807
 808         return sent ? sent : err;
 809 }
 810
 811 static int rfcomm_tty_write_room(struct tty_struct *tty)
 812 {
 813         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
 814         int room;
 815
 816         BT_DBG("tty %p", tty);
 817
 818         if (!dev || !dev->dlc)
 819                 return 0;
 820
 821         room = rfcomm_room(dev->dlc) - atomic_read(&dev->wmem_alloc);
 822         if (room < 0)
 823                 room = 0;
 824
 825         return room;
 826 }
 827
 828 static int rfcomm_tty_ioctl(struct tty_struct *tty, struct file *filp, unsigned int cmd, unsigned long arg)
 829 {
 830         BT_DBG("tty %p cmd 0x%02x", tty, cmd);
 831
 832         switch (cmd) {
 833         case TCGETS:
 834                 BT_DBG("TCGETS is not supported");
 835                 return -ENOIOCTLCMD;
 836
 837         case TCSETS:
 838                 BT_DBG("TCSETS is not supported");
 839                 return -ENOIOCTLCMD;
 840
 841         case TIOCMIWAIT:
 842                 BT_DBG("TIOCMIWAIT");
 843                 break;
 844
 845         case TIOCGICOUNT:
 846                 BT_DBG("TIOCGICOUNT");
 847                 break;
 848
 849         case TIOCGSERIAL:
 850                 BT_ERR("TIOCGSERIAL is not supported");
 851                 return -ENOIOCTLCMD;
 852
 853         case TIOCSSERIAL:
 854                 BT_ERR("TIOCSSERIAL is not supported");
 855                 return -ENOIOCTLCMD;
 856
 857         case TIOCSERGSTRUCT:
 858                 BT_ERR("TIOCSERGSTRUCT is not supported");
 859                 return -ENOIOCTLCMD;
 860
 861         case TIOCSERGETLSR:
 862                 BT_ERR("TIOCSERGETLSR is not supported");
 863                 return -ENOIOCTLCMD;
 864
 865         case TIOCSERCONFIG:
 866                 BT_ERR("TIOCSERCONFIG is not supported");
 867                 return -ENOIOCTLCMD;
 868
 869         default:
 870                 return -ENOIOCTLCMD;    /* ioctls which we must ignore */
 871
 872         }
 873
 874         return -ENOIOCTLCMD;
 875 }
 876
 877 static void rfcomm_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
 878 {
 879         struct ktermios *new = tty->termios;
 880         int old_baud_rate = tty_termios_baud_rate(old);
 881         int new_baud_rate = tty_termios_baud_rate(new);
 882
 883         u8 baud, data_bits, stop_bits, parity, x_on, x_off;
 884         u16 changes = 0;
 885
 886         struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
 887
 888         BT_DBG("tty %p termios %p", tty, old);
 889
 890         if (!dev || !dev->dlc || !dev->dlc->session)
 891                 return;
 892
 893         /* Handle turning off CRTSCTS */
 894         if ((old->c_cflag & CRTSCTS) && !(new->c_cflag & CRTSCTS))
 895                 BT_DBG("Turning off CRTSCTS unsupported");
 896
 897         /* Parity on/off and when on, odd/even */
 898         if (((old->c_cflag & PARENB) != (new->c_cflag & PARENB)) ||
 899                         ((old->c_cflag & PARODD) != (new->c_cflag & PARODD)) ) {
 900                 changes |= RFCOMM_RPN_PM_PARITY;
 901                 BT_DBG("Parity change detected.");
 902         }
 903
 904         /* Mark and space parity are not supported! */
 905         if (new->c_cflag & PARENB) {
 906                 if (new->c_cflag & PARODD) {
 907                         BT_DBG("Parity is ODD");
 908                         parity = RFCOMM_RPN_PARITY_ODD;
 909                 } else {
 910                         BT_DBG("Parity is EVEN");
 911                         parity = RFCOMM_RPN_PARITY_EVEN;
 912                 }
 913         } else {
 914                 BT_DBG("Parity is OFF");
 915                 parity = RFCOMM_RPN_PARITY_NONE;
 916         }
 917
 918         /* Setting the x_on / x_off characters */
 919         if (old->c_cc[VSTOP] != new->c_cc[VSTOP]) {
 920                 BT_DBG("XOFF custom");
 921                 x_on = new->c_cc[VSTOP];
 922                 changes |= RFCOMM_RPN_PM_XON;
 923         } else {
 924                 BT_DBG("XOFF default");
 925                 x_on = RFCOMM_RPN_XON_CHAR;
 926         }
 927
 928         if (old->c_cc[VSTART] != new->c_cc[VSTART]) {
 929                 BT_DBG("XON custom");
 930                 x_off = new->c_cc[VSTART];
 931                 changes |= RFCOMM_RPN_PM_XOFF;
 932         } else {
 933                 BT_DBG("XON default");
 934                 x_off = RFCOMM_RPN_XOFF_CHAR;
 935         }
 936
 937         /* Handle setting of stop bits */
 938         if ((old->c_cflag & CSTOPB) != (new->c_cflag & CSTOPB))
 939                 changes |= RFCOMM_RPN_PM_STOP;
 940
 941         /* POSIX does not support 1.5 stop bits and RFCOMM does not
 942          * support 2 stop bits. So a request for 2 stop bits gets
 943          * translated to 1.5 stop bits */
 944         if (new->c_cflag & CSTOPB) {
 945                 stop_bits = RFCOMM_RPN_STOP_15;
 946         } else {
 947                 stop_bits = RFCOMM_RPN_STOP_1;
 948         }
 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, struct file *filp)
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 }