drivers/staging/usbip/stub_dev.c

   1 /*
   2  * Copyright (C) 2003-2008 Takahiro Hirofuchi
   3  *
   4  * This is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  17  * USA.
  18  */
  19
  20 #include <linux/slab.h>
  21
  22 #include "usbip_common.h"
  23 #include "stub.h"
  24
  25
  26
  27 static int stub_probe(struct usb_interface *interface,
  28                                 const struct usb_device_id *id);
  29 static void stub_disconnect(struct usb_interface *interface);
  30
  31
  32 /*
  33  * Define device IDs here if you want to explicitly limit exportable devices.
  34  * In the most cases, wild card matching will be ok because driver binding can
  35  * be changed dynamically by a userland program.
  36  */
  37 static struct usb_device_id stub_table[] = {
  38 #if 0
  39         /* just an example */
  40         { USB_DEVICE(0x05ac, 0x0301) },   /* Mac 1 button mouse */
  41         { USB_DEVICE(0x0430, 0x0009) },   /* Plat Home Keyboard */
  42         { USB_DEVICE(0x059b, 0x0001) },   /* Iomega USB Zip 100 */
  43         { USB_DEVICE(0x04b3, 0x4427) },   /* IBM USB CD-ROM */
  44         { USB_DEVICE(0x05a9, 0xa511) },   /* LifeView USB cam */
  45         { USB_DEVICE(0x55aa, 0x0201) },   /* Imation card reader */
  46         { USB_DEVICE(0x046d, 0x0870) },   /* Qcam Express(QV-30) */
  47         { USB_DEVICE(0x04bb, 0x0101) },   /* IO-DATA HD 120GB */
  48         { USB_DEVICE(0x04bb, 0x0904) },   /* IO-DATA USB-ET/TX */
  49         { USB_DEVICE(0x04bb, 0x0201) },   /* IO-DATA USB-ET/TX */
  50         { USB_DEVICE(0x08bb, 0x2702) },   /* ONKYO USB Speaker */
  51         { USB_DEVICE(0x046d, 0x08b2) },   /* Logicool Qcam 4000 Pro */
  52 #endif
  53         /* magic for wild card */
  54         { .driver_info = 1 },
  55         { 0, }                                     /* Terminating entry */
  56 };
  57 MODULE_DEVICE_TABLE(usb, stub_table);
  58
  59 struct usb_driver stub_driver = {
  60         .name           = "usbip",
  61         .probe          = stub_probe,
  62         .disconnect     = stub_disconnect,
  63         .id_table       = stub_table,
  64 };
  65
  66
  67 /*-------------------------------------------------------------------------*/
  68
  69 /* Define sysfs entries for a usbip-bound device */
  70
  71
  72 /*
  73  * usbip_status shows status of usbip as long as this driver is bound to the
  74  * target device.
  75  */
  76 static ssize_t show_status(struct device *dev, struct device_attribute *attr,
  77                            char *buf)
  78 {
  79         struct stub_device *sdev = dev_get_drvdata(dev);
  80         int status;
  81
  82         if (!sdev) {
  83                 dev_err(dev, "sdev is null\n");
  84                 return -ENODEV;
  85         }
  86
  87         spin_lock(&sdev->ud.lock);
  88         status = sdev->ud.status;
  89         spin_unlock(&sdev->ud.lock);
  90
  91         return snprintf(buf, PAGE_SIZE, "%d\n", status);
  92 }
  93 static DEVICE_ATTR(usbip_status, S_IRUGO, show_status, NULL);
  94
  95 /*
  96  * usbip_sockfd gets a socket descriptor of an established TCP connection that
  97  * is used to transfer usbip requests by kernel threads. -1 is a magic number
  98  * by which usbip connection is finished.
  99  */
 100 static ssize_t store_sockfd(struct device *dev, struct device_attribute *attr,
 101                             const char *buf, size_t count)
 102 {
 103         struct stub_device *sdev = dev_get_drvdata(dev);
 104         int sockfd = 0;
 105         struct socket *socket;
 106
 107         if (!sdev) {
 108                 dev_err(dev, "sdev is null\n");
 109                 return -ENODEV;
 110         }
 111
 112         sscanf(buf, "%d", &sockfd);
 113
 114         if (sockfd != -1) {
 115                 dev_info(dev, "stub up\n");
 116
 117                 spin_lock(&sdev->ud.lock);
 118
 119                 if (sdev->ud.status != SDEV_ST_AVAILABLE) {
 120                         dev_err(dev, "not ready\n");
 121                         spin_unlock(&sdev->ud.lock);
 122                         return -EINVAL;
 123                 }
 124
 125                 socket = sockfd_to_socket(sockfd);
 126                 if (!socket) {
 127                         spin_unlock(&sdev->ud.lock);
 128                         return -EINVAL;
 129                 }
 130
 131 #if 0
 132                 setnodelay(socket);
 133                 setkeepalive(socket);
 134                 setreuse(socket);
 135 #endif
 136
 137                 sdev->ud.tcp_socket = socket;
 138
 139                 spin_unlock(&sdev->ud.lock);
 140
 141                 usbip_start_threads(&sdev->ud);
 142
 143                 spin_lock(&sdev->ud.lock);
 144                 sdev->ud.status = SDEV_ST_USED;
 145                 spin_unlock(&sdev->ud.lock);
 146
 147         } else {
 148                 dev_info(dev, "stub down\n");
 149
 150                 spin_lock(&sdev->ud.lock);
 151                 if (sdev->ud.status != SDEV_ST_USED) {
 152                         spin_unlock(&sdev->ud.lock);
 153                         return -EINVAL;
 154                 }
 155                 spin_unlock(&sdev->ud.lock);
 156
 157                 usbip_event_add(&sdev->ud, SDEV_EVENT_DOWN);
 158         }
 159
 160         return count;
 161 }
 162 static DEVICE_ATTR(usbip_sockfd, S_IWUSR, NULL, store_sockfd);
 163
 164 static int stub_add_files(struct device *dev)
 165 {
 166         int err = 0;
 167
 168         err = device_create_file(dev, &dev_attr_usbip_status);
 169         if (err)
 170                 goto err_status;
 171
 172         err = device_create_file(dev, &dev_attr_usbip_sockfd);
 173         if (err)
 174                 goto err_sockfd;
 175
 176         err = device_create_file(dev, &dev_attr_usbip_debug);
 177         if (err)
 178                 goto err_debug;
 179
 180         return 0;
 181
 182 err_debug:
 183         device_remove_file(dev, &dev_attr_usbip_sockfd);
 184
 185 err_sockfd:
 186         device_remove_file(dev, &dev_attr_usbip_status);
 187
 188 err_status:
 189         return err;
 190 }
 191
 192 static void stub_remove_files(struct device *dev)
 193 {
 194         device_remove_file(dev, &dev_attr_usbip_status);
 195         device_remove_file(dev, &dev_attr_usbip_sockfd);
 196         device_remove_file(dev, &dev_attr_usbip_debug);
 197 }
 198
 199
 200
 201 /*-------------------------------------------------------------------------*/
 202
 203 /* Event handler functions called by an event handler thread */
 204
 205 static void stub_shutdown_connection(struct usbip_device *ud)
 206 {
 207         struct stub_device *sdev = container_of(ud, struct stub_device, ud);
 208
 209         /*
 210          * When removing an exported device, kernel panic sometimes occurred
 211          * and then EIP was sk_wait_data of stub_rx thread. Is this because
 212          * sk_wait_data returned though stub_rx thread was already finished by
 213          * step 1?
 214          */
 215         if (ud->tcp_socket) {
 216                 usbip_udbg("shutdown tcp_socket %p\n", ud->tcp_socket);
 217                 kernel_sock_shutdown(ud->tcp_socket, SHUT_RDWR);
 218         }
 219
 220         /* 1. stop threads */
 221         usbip_stop_threads(ud);
 222
 223         /* 2. close the socket */
 224         /*
 225          * tcp_socket is freed after threads are killed.
 226          * So usbip_xmit do not touch NULL socket.
 227          */
 228         if (ud->tcp_socket) {
 229                 sock_release(ud->tcp_socket);
 230                 ud->tcp_socket = NULL;
 231         }
 232
 233         /* 3. free used data */
 234         stub_device_cleanup_urbs(sdev);
 235
 236         /* 4. free stub_unlink */
 237         {
 238                 unsigned long flags;
 239                 struct stub_unlink *unlink, *tmp;
 240
 241                 spin_lock_irqsave(&sdev->priv_lock, flags);
 242
 243                 list_for_each_entry_safe(unlink, tmp, &sdev->unlink_tx, list) {
 244                         list_del(&unlink->list);
 245                         kfree(unlink);
 246                 }
 247
 248                 list_for_each_entry_safe(unlink, tmp,
 249                                                  &sdev->unlink_free, list) {
 250                         list_del(&unlink->list);
 251                         kfree(unlink);
 252                 }
 253
 254                 spin_unlock_irqrestore(&sdev->priv_lock, flags);
 255         }
 256 }
 257
 258 static void stub_device_reset(struct usbip_device *ud)
 259 {
 260         struct stub_device *sdev = container_of(ud, struct stub_device, ud);
 261         struct usb_device *udev = sdev->udev;
 262         int ret;
 263
 264         usbip_udbg("device reset");
 265
 266         ret = usb_lock_device_for_reset(udev, sdev->interface);
 267         if (ret < 0) {
 268                 dev_err(&udev->dev, "lock for reset\n");
 269
 270                 spin_lock(&ud->lock);
 271                 ud->status = SDEV_ST_ERROR;
 272                 spin_unlock(&ud->lock);
 273
 274                 return;
 275         }
 276
 277         /* try to reset the device */
 278         ret = usb_reset_device(udev);
 279
 280         usb_unlock_device(udev);
 281
 282         spin_lock(&ud->lock);
 283         if (ret) {
 284                 dev_err(&udev->dev, "device reset\n");
 285                 ud->status = SDEV_ST_ERROR;
 286
 287         } else {
 288                 dev_info(&udev->dev, "device reset\n");
 289                 ud->status = SDEV_ST_AVAILABLE;
 290
 291         }
 292         spin_unlock(&ud->lock);
 293
 294         return;
 295 }
 296
 297 static void stub_device_unusable(struct usbip_device *ud)
 298 {
 299         spin_lock(&ud->lock);
 300         ud->status = SDEV_ST_ERROR;
 301         spin_unlock(&ud->lock);
 302 }
 303
 304
 305 /*-------------------------------------------------------------------------*/
 306
 307 /**
 308  * stub_device_alloc - allocate a new stub_device struct
 309  * @interface: usb_interface of a new device
 310  *
 311  * Allocates and initializes a new stub_device struct.
 312  */
 313 static struct stub_device *stub_device_alloc(struct usb_device *udev,
 314                                              struct usb_interface *interface)
 315 {
 316         struct stub_device *sdev;
 317         int busnum = interface_to_busnum(interface);
 318         int devnum = interface_to_devnum(interface);
 319
 320         dev_dbg(&interface->dev, "allocating stub device");
 321
 322         /* yes, it's a new device */
 323         sdev = kzalloc(sizeof(struct stub_device), GFP_KERNEL);
 324         if (!sdev) {
 325                 dev_err(&interface->dev, "no memory for stub_device\n");
 326                 return NULL;
 327         }
 328
 329         sdev->interface = usb_get_intf(interface);
 330         sdev->udev = usb_get_dev(udev);
 331
 332         /*
 333          * devid is defined with devnum when this driver is first allocated.
 334          * devnum may change later if a device is reset. However, devid never
 335          * changes during a usbip connection.
 336          */
 337         sdev->devid     = (busnum << 16) | devnum;
 338
 339         usbip_task_init(&sdev->ud.tcp_rx, "stub_rx", stub_rx_loop);
 340         usbip_task_init(&sdev->ud.tcp_tx, "stub_tx", stub_tx_loop);
 341
 342         sdev->ud.side = USBIP_STUB;
 343         sdev->ud.status = SDEV_ST_AVAILABLE;
 344         /* sdev->ud.lock = SPIN_LOCK_UNLOCKED; */
 345         spin_lock_init(&sdev->ud.lock);
 346         sdev->ud.tcp_socket = NULL;
 347
 348         INIT_LIST_HEAD(&sdev->priv_init);
 349         INIT_LIST_HEAD(&sdev->priv_tx);
 350         INIT_LIST_HEAD(&sdev->priv_free);
 351         INIT_LIST_HEAD(&sdev->unlink_free);
 352         INIT_LIST_HEAD(&sdev->unlink_tx);
 353         /* sdev->priv_lock = SPIN_LOCK_UNLOCKED; */
 354         spin_lock_init(&sdev->priv_lock);
 355
 356         init_waitqueue_head(&sdev->tx_waitq);
 357
 358         sdev->ud.eh_ops.shutdown = stub_shutdown_connection;
 359         sdev->ud.eh_ops.reset    = stub_device_reset;
 360         sdev->ud.eh_ops.unusable = stub_device_unusable;
 361
 362         usbip_start_eh(&sdev->ud);
 363
 364         usbip_udbg("register new interface\n");
 365         return sdev;
 366 }
 367
 368 static int stub_device_free(struct stub_device *sdev)
 369 {
 370         if (!sdev)
 371                 return -EINVAL;
 372
 373         kfree(sdev);
 374         usbip_udbg("kfree udev ok\n");
 375
 376         return 0;
 377 }
 378
 379
 380 /*-------------------------------------------------------------------------*/
 381
 382 /*
 383  * If a usb device has multiple active interfaces, this driver is bound to all
 384  * the active interfaces. However, usbip exports *a* usb device (i.e., not *an*
 385  * active interface). Currently, a userland program must ensure that it
 386  * looks at the usbip's sysfs entries of only the first active interface.
 387  *
 388  * TODO: use "struct usb_device_driver" to bind a usb device.
 389  * However, it seems it is not fully supported in mainline kernel yet
 390  * (2.6.19.2).
 391  */
 392 static int stub_probe(struct usb_interface *interface,
 393                       const struct usb_device_id *id)
 394 {
 395         struct usb_device *udev = interface_to_usbdev(interface);
 396         struct stub_device *sdev = NULL;
 397         const char *udev_busid = dev_name(interface->dev.parent);
 398         int err = 0;
 399         struct bus_id_priv *busid_priv;
 400
 401         dev_dbg(&interface->dev, "Enter\n");
 402
 403         /* check we should claim or not by busid_table */
 404         busid_priv = get_busid_priv(udev_busid);
 405         if (!busid_priv  || (busid_priv->status == STUB_BUSID_REMOV) ||
 406                              (busid_priv->status == STUB_BUSID_OTHER)) {
 407                 dev_info(&interface->dev,
 408                          "this device %s is not in match_busid table. skip!\n",
 409                          udev_busid);
 410
 411                 /*
 412                  * Return value should be ENODEV or ENOXIO to continue trying
 413                  * other matched drivers by the driver core.
 414                  * See driver_probe_device() in driver/base/dd.c
 415                  */
 416                 return -ENODEV;
 417         }
 418
 419         if (udev->descriptor.bDeviceClass ==  USB_CLASS_HUB) {
 420                 usbip_udbg("this device %s is a usb hub device. skip!\n",
 421                                                                 udev_busid);
 422                 return -ENODEV;
 423         }
 424
 425         if (!strcmp(udev->bus->bus_name, "vhci_hcd")) {
 426                 usbip_udbg("this device %s is attached on vhci_hcd. skip!\n",
 427                                                                 udev_busid);
 428                 return -ENODEV;
 429         }
 430
 431
 432         if (busid_priv->status == STUB_BUSID_ALLOC) {
 433                 sdev = busid_priv->sdev;
 434                 if (!sdev)
 435                         return -ENODEV;
 436
 437                 busid_priv->interf_count++;
 438                 dev_info(&interface->dev,
 439                  "USB/IP Stub: register a new interface "
 440                  "(bus %u dev %u ifn %u)\n", udev->bus->busnum, udev->devnum,
 441                  interface->cur_altsetting->desc.bInterfaceNumber);
 442
 443                 /* set private data to usb_interface */
 444                 usb_set_intfdata(interface, sdev);
 445
 446                 err = stub_add_files(&interface->dev);
 447                 if (err) {
 448                         dev_err(&interface->dev, "create sysfs files for %s\n",
 449                                 udev_busid);
 450                         usb_set_intfdata(interface, NULL);
 451                         busid_priv->interf_count--;
 452
 453                         return err;
 454                 }
 455
 456                 usb_get_intf(interface);
 457                 return 0;
 458         }
 459
 460         /* ok. this is my device. */
 461         sdev = stub_device_alloc(udev, interface);
 462         if (!sdev)
 463                 return -ENOMEM;
 464
 465         dev_info(&interface->dev, "USB/IP Stub: register a new device "
 466                  "(bus %u dev %u ifn %u)\n", udev->bus->busnum, udev->devnum,
 467                  interface->cur_altsetting->desc.bInterfaceNumber);
 468
 469         busid_priv->interf_count = 0;
 470         busid_priv->shutdown_busid = 0;
 471
 472         /* set private data to usb_interface */
 473         usb_set_intfdata(interface, sdev);
 474         busid_priv->interf_count++;
 475
 476         busid_priv->sdev = sdev;
 477
 478         err = stub_add_files(&interface->dev);
 479         if (err) {
 480                 dev_err(&interface->dev, "create sysfs files for %s\n",
 481                         udev_busid);
 482                 usb_set_intfdata(interface, NULL);
 483                 usb_put_intf(interface);
 484
 485                 busid_priv->interf_count = 0;
 486
 487                 busid_priv->sdev = NULL;
 488                 stub_device_free(sdev);
 489                 return err;
 490         }
 491         busid_priv->status = STUB_BUSID_ALLOC;
 492
 493         return 0;
 494 }
 495
 496 static void shutdown_busid(struct bus_id_priv *busid_priv)
 497 {
 498         if (busid_priv->sdev && !busid_priv->shutdown_busid) {
 499                 busid_priv->shutdown_busid = 1;
 500                 usbip_event_add(&busid_priv->sdev->ud, SDEV_EVENT_REMOVED);
 501
 502                 /* 2. wait for the stop of the event handler */
 503                 usbip_stop_eh(&busid_priv->sdev->ud);
 504         }
 505
 506 }
 507
 508
 509 /*
 510  * called in usb_disconnect() or usb_deregister()
 511  * but only if actconfig(active configuration) exists
 512  */
 513 static void stub_disconnect(struct usb_interface *interface)
 514 {
 515         struct stub_device *sdev;
 516         const char *udev_busid = dev_name(interface->dev.parent);
 517         struct bus_id_priv *busid_priv;
 518
 519         busid_priv = get_busid_priv(udev_busid);
 520
 521         usbip_udbg("Enter\n");
 522
 523         if (!busid_priv) {
 524                 BUG();
 525                 return;
 526         }
 527
 528         sdev = usb_get_intfdata(interface);
 529
 530         /* get stub_device */
 531         if (!sdev) {
 532                 err(" could not get device from inteface data");
 533                 /* BUG(); */
 534                 return;
 535         }
 536
 537         usb_set_intfdata(interface, NULL);
 538
 539         /*
 540          * NOTE:
 541          * rx/tx threads are invoked for each usb_device.
 542          */
 543         stub_remove_files(&interface->dev);
 544
 545         /*If usb reset called from event handler*/
 546         if (busid_priv->sdev->ud.eh.thread == current) {
 547                 busid_priv->interf_count--;
 548                 return;
 549         }
 550
 551         if (busid_priv->interf_count > 1) {
 552                 busid_priv->interf_count--;
 553                 shutdown_busid(busid_priv);
 554                 usb_put_intf(interface);
 555                 return;
 556         }
 557
 558         busid_priv->interf_count = 0;
 559
 560
 561         /* 1. shutdown the current connection */
 562         shutdown_busid(busid_priv);
 563
 564         usb_put_dev(sdev->udev);
 565         usb_put_intf(interface);
 566
 567         /* 3. free sdev */
 568         busid_priv->sdev = NULL;
 569         stub_device_free(sdev);
 570
 571         if (busid_priv->status == STUB_BUSID_ALLOC) {
 572                 busid_priv->status = STUB_BUSID_ADDED;
 573         } else {
 574                 busid_priv->status = STUB_BUSID_OTHER;
 575                 del_match_busid((char *)udev_busid);
 576         }
 577         usbip_udbg("bye\n");
 578 }