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