drivers/usb/usbip/usbip_common.c

   1 /*
   2  * Copyright (C) 2003-2008 Takahiro Hirofuchi
   3  * Copyright (C) 2015-2016 Samsung Electronics
   4  *               Krzysztof Opasiak <k.opasiak@samsung.com>
   5  *
   6  * This is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  19  * USA.
  20  */
  21
  22 #include <asm/byteorder.h>
  23 #include <linux/file.h>
  24 #include <linux/fs.h>
  25 #include <linux/kernel.h>
  26 #include <linux/slab.h>
  27 #include <linux/stat.h>
  28 #include <linux/module.h>
  29 #include <linux/moduleparam.h>
  30 #include <net/sock.h>
  31
  32 #include "usbip_common.h"
  33
  34 #define DRIVER_AUTHOR "Takahiro Hirofuchi <hirofuchi@users.sourceforge.net>"
  35 #define DRIVER_DESC "USB/IP Core"
  36
  37 #ifdef CONFIG_USBIP_DEBUG
  38 unsigned long usbip_debug_flag = 0xffffffff;
  39 #else
  40 unsigned long usbip_debug_flag;
  41 #endif
  42 EXPORT_SYMBOL_GPL(usbip_debug_flag);
  43 module_param(usbip_debug_flag, ulong, S_IRUGO|S_IWUSR);
  44 MODULE_PARM_DESC(usbip_debug_flag, "debug flags (defined in usbip_common.h)");
  45
  46 /* FIXME */
  47 struct device_attribute dev_attr_usbip_debug;
  48 EXPORT_SYMBOL_GPL(dev_attr_usbip_debug);
  49
  50 static ssize_t usbip_debug_show(struct device *dev,
  51                                 struct device_attribute *attr, char *buf)
  52 {
  53         return sprintf(buf, "%lx\n", usbip_debug_flag);
  54 }
  55
  56 static ssize_t usbip_debug_store(struct device *dev,
  57                                  struct device_attribute *attr, const char *buf,
  58                                  size_t count)
  59 {
  60         if (sscanf(buf, "%lx", &usbip_debug_flag) != 1)
  61                 return -EINVAL;
  62         return count;
  63 }
  64 DEVICE_ATTR_RW(usbip_debug);
  65
  66 static void usbip_dump_buffer(char *buff, int bufflen)
  67 {
  68         print_hex_dump(KERN_DEBUG, "usbip-core", DUMP_PREFIX_OFFSET, 16, 4,
  69                        buff, bufflen, false);
  70 }
  71
  72 static void usbip_dump_pipe(unsigned int p)
  73 {
  74         unsigned char type = usb_pipetype(p);
  75         unsigned char ep   = usb_pipeendpoint(p);
  76         unsigned char dev  = usb_pipedevice(p);
  77         unsigned char dir  = usb_pipein(p);
  78
  79         pr_debug("dev(%d) ep(%d) [%s] ", dev, ep, dir ? "IN" : "OUT");
  80
  81         switch (type) {
  82         case PIPE_ISOCHRONOUS:
  83                 pr_debug("ISO\n");
  84                 break;
  85         case PIPE_INTERRUPT:
  86                 pr_debug("INT\n");
  87                 break;
  88         case PIPE_CONTROL:
  89                 pr_debug("CTRL\n");
  90                 break;
  91         case PIPE_BULK:
  92                 pr_debug("BULK\n");
  93                 break;
  94         default:
  95                 pr_debug("ERR\n");
  96                 break;
  97         }
  98 }
  99
 100 static void usbip_dump_usb_device(struct usb_device *udev)
 101 {
 102         struct device *dev = &udev->dev;
 103         int i;
 104
 105         dev_dbg(dev, "       devnum(%d) devpath(%s) usb speed(%s)",
 106                 udev->devnum, udev->devpath, usb_speed_string(udev->speed));
 107
 108         pr_debug("tt %p, ttport %d\n", udev->tt, udev->ttport);
 109
 110         dev_dbg(dev, "                    ");
 111         for (i = 0; i < 16; i++)
 112                 pr_debug(" %2u", i);
 113         pr_debug("\n");
 114
 115         dev_dbg(dev, "       toggle0(IN) :");
 116         for (i = 0; i < 16; i++)
 117                 pr_debug(" %2u", (udev->toggle[0] & (1 << i)) ? 1 : 0);
 118         pr_debug("\n");
 119
 120         dev_dbg(dev, "       toggle1(OUT):");
 121         for (i = 0; i < 16; i++)
 122                 pr_debug(" %2u", (udev->toggle[1] & (1 << i)) ? 1 : 0);
 123         pr_debug("\n");
 124
 125         dev_dbg(dev, "       epmaxp_in   :");
 126         for (i = 0; i < 16; i++) {
 127                 if (udev->ep_in[i])
 128                         pr_debug(" %2u",
 129                             le16_to_cpu(udev->ep_in[i]->desc.wMaxPacketSize));
 130         }
 131         pr_debug("\n");
 132
 133         dev_dbg(dev, "       epmaxp_out  :");
 134         for (i = 0; i < 16; i++) {
 135                 if (udev->ep_out[i])
 136                         pr_debug(" %2u",
 137                             le16_to_cpu(udev->ep_out[i]->desc.wMaxPacketSize));
 138         }
 139         pr_debug("\n");
 140
 141         dev_dbg(dev, "parent %p, bus %p\n", udev->parent, udev->bus);
 142
 143         dev_dbg(dev,
 144                 "descriptor %p, config %p, actconfig %p, rawdescriptors %p\n",
 145                 &udev->descriptor, udev->config,
 146                 udev->actconfig, udev->rawdescriptors);
 147
 148         dev_dbg(dev, "have_langid %d, string_langid %d\n",
 149                 udev->have_langid, udev->string_langid);
 150
 151         dev_dbg(dev, "maxchild %d\n", udev->maxchild);
 152 }
 153
 154 static void usbip_dump_request_type(__u8 rt)
 155 {
 156         switch (rt & USB_RECIP_MASK) {
 157         case USB_RECIP_DEVICE:
 158                 pr_debug("DEVICE");
 159                 break;
 160         case USB_RECIP_INTERFACE:
 161                 pr_debug("INTERF");
 162                 break;
 163         case USB_RECIP_ENDPOINT:
 164                 pr_debug("ENDPOI");
 165                 break;
 166         case USB_RECIP_OTHER:
 167                 pr_debug("OTHER ");
 168                 break;
 169         default:
 170                 pr_debug("------");
 171                 break;
 172         }
 173 }
 174
 175 static void usbip_dump_usb_ctrlrequest(struct usb_ctrlrequest *cmd)
 176 {
 177         if (!cmd) {
 178                 pr_debug("       : null pointer\n");
 179                 return;
 180         }
 181
 182         pr_debug("       ");
 183         pr_debug("bRequestType(%02X) bRequest(%02X) wValue(%04X) wIndex(%04X) wLength(%04X) ",
 184                  cmd->bRequestType, cmd->bRequest,
 185                  cmd->wValue, cmd->wIndex, cmd->wLength);
 186         pr_debug("\n       ");
 187
 188         if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD) {
 189                 pr_debug("STANDARD ");
 190                 switch (cmd->bRequest) {
 191                 case USB_REQ_GET_STATUS:
 192                         pr_debug("GET_STATUS\n");
 193                         break;
 194                 case USB_REQ_CLEAR_FEATURE:
 195                         pr_debug("CLEAR_FEAT\n");
 196                         break;
 197                 case USB_REQ_SET_FEATURE:
 198                         pr_debug("SET_FEAT\n");
 199                         break;
 200                 case USB_REQ_SET_ADDRESS:
 201                         pr_debug("SET_ADDRRS\n");
 202                         break;
 203                 case USB_REQ_GET_DESCRIPTOR:
 204                         pr_debug("GET_DESCRI\n");
 205                         break;
 206                 case USB_REQ_SET_DESCRIPTOR:
 207                         pr_debug("SET_DESCRI\n");
 208                         break;
 209                 case USB_REQ_GET_CONFIGURATION:
 210                         pr_debug("GET_CONFIG\n");
 211                         break;
 212                 case USB_REQ_SET_CONFIGURATION:
 213                         pr_debug("SET_CONFIG\n");
 214                         break;
 215                 case USB_REQ_GET_INTERFACE:
 216                         pr_debug("GET_INTERF\n");
 217                         break;
 218                 case USB_REQ_SET_INTERFACE:
 219                         pr_debug("SET_INTERF\n");
 220                         break;
 221                 case USB_REQ_SYNCH_FRAME:
 222                         pr_debug("SYNC_FRAME\n");
 223                         break;
 224                 default:
 225                         pr_debug("REQ(%02X)\n", cmd->bRequest);
 226                         break;
 227                 }
 228                 usbip_dump_request_type(cmd->bRequestType);
 229         } else if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_CLASS) {
 230                 pr_debug("CLASS\n");
 231         } else if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_VENDOR) {
 232                 pr_debug("VENDOR\n");
 233         } else if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_RESERVED) {
 234                 pr_debug("RESERVED\n");
 235         }
 236 }
 237
 238 void usbip_dump_urb(struct urb *urb)
 239 {
 240         struct device *dev;
 241
 242         if (!urb) {
 243                 pr_debug("urb: null pointer!!\n");
 244                 return;
 245         }
 246
 247         if (!urb->dev) {
 248                 pr_debug("urb->dev: null pointer!!\n");
 249                 return;
 250         }
 251
 252         dev = &urb->dev->dev;
 253
 254         dev_dbg(dev, "   urb                   :%p\n", urb);
 255         dev_dbg(dev, "   dev                   :%p\n", urb->dev);
 256
 257         usbip_dump_usb_device(urb->dev);
 258
 259         dev_dbg(dev, "   pipe                  :%08x ", urb->pipe);
 260
 261         usbip_dump_pipe(urb->pipe);
 262
 263         dev_dbg(dev, "   status                :%d\n", urb->status);
 264         dev_dbg(dev, "   transfer_flags        :%08X\n", urb->transfer_flags);
 265         dev_dbg(dev, "   transfer_buffer       :%p\n", urb->transfer_buffer);
 266         dev_dbg(dev, "   transfer_buffer_length:%d\n",
 267                                                 urb->transfer_buffer_length);
 268         dev_dbg(dev, "   actual_length         :%d\n", urb->actual_length);
 269         dev_dbg(dev, "   setup_packet          :%p\n", urb->setup_packet);
 270
 271         if (urb->setup_packet && usb_pipetype(urb->pipe) == PIPE_CONTROL)
 272                 usbip_dump_usb_ctrlrequest(
 273                         (struct usb_ctrlrequest *)urb->setup_packet);
 274
 275         dev_dbg(dev, "   start_frame           :%d\n", urb->start_frame);
 276         dev_dbg(dev, "   number_of_packets     :%d\n", urb->number_of_packets);
 277         dev_dbg(dev, "   interval              :%d\n", urb->interval);
 278         dev_dbg(dev, "   error_count           :%d\n", urb->error_count);
 279         dev_dbg(dev, "   context               :%p\n", urb->context);
 280         dev_dbg(dev, "   complete              :%p\n", urb->complete);
 281 }
 282 EXPORT_SYMBOL_GPL(usbip_dump_urb);
 283
 284 void usbip_dump_header(struct usbip_header *pdu)
 285 {
 286         pr_debug("BASE: cmd %u seq %u devid %u dir %u ep %u\n",
 287                  pdu->base.command,
 288                  pdu->base.seqnum,
 289                  pdu->base.devid,
 290                  pdu->base.direction,
 291                  pdu->base.ep);
 292
 293         switch (pdu->base.command) {
 294         case USBIP_CMD_SUBMIT:
 295                 pr_debug("USBIP_CMD_SUBMIT: x_flags %u x_len %u sf %u #p %d iv %d\n",
 296                          pdu->u.cmd_submit.transfer_flags,
 297                          pdu->u.cmd_submit.transfer_buffer_length,
 298                          pdu->u.cmd_submit.start_frame,
 299                          pdu->u.cmd_submit.number_of_packets,
 300                          pdu->u.cmd_submit.interval);
 301                 break;
 302         case USBIP_CMD_UNLINK:
 303                 pr_debug("USBIP_CMD_UNLINK: seq %u\n",
 304                          pdu->u.cmd_unlink.seqnum);
 305                 break;
 306         case USBIP_RET_SUBMIT:
 307                 pr_debug("USBIP_RET_SUBMIT: st %d al %u sf %d #p %d ec %d\n",
 308                          pdu->u.ret_submit.status,
 309                          pdu->u.ret_submit.actual_length,
 310                          pdu->u.ret_submit.start_frame,
 311                          pdu->u.ret_submit.number_of_packets,
 312                          pdu->u.ret_submit.error_count);
 313                 break;
 314         case USBIP_RET_UNLINK:
 315                 pr_debug("USBIP_RET_UNLINK: status %d\n",
 316                          pdu->u.ret_unlink.status);
 317                 break;
 318         default:
 319                 /* NOT REACHED */
 320                 pr_err("unknown command\n");
 321                 break;
 322         }
 323 }
 324 EXPORT_SYMBOL_GPL(usbip_dump_header);
 325
 326 /* Receive data over TCP/IP. */
 327 int usbip_recv(struct socket *sock, void *buf, int size)
 328 {
 329         int result;
 330         struct kvec iov = {.iov_base = buf, .iov_len = size};
 331         struct msghdr msg = {.msg_flags = MSG_NOSIGNAL};
 332         int total = 0;
 333
 334         iov_iter_kvec(&msg.msg_iter, READ|ITER_KVEC, &iov, 1, size);
 335
 336         usbip_dbg_xmit("enter\n");
 337
 338         if (!sock || !buf || !size) {
 339                 pr_err("invalid arg, sock %p buff %p size %d\n", sock, buf,
 340                        size);
 341                 return -EINVAL;
 342         }
 343
 344         do {
 345                 int sz = msg_data_left(&msg);
 346                 sock->sk->sk_allocation = GFP_NOIO;
 347
 348                 result = sock_recvmsg(sock, &msg, MSG_WAITALL);
 349                 if (result <= 0) {
 350                         pr_debug("receive sock %p buf %p size %u ret %d total %d\n",
 351                                  sock, buf + total, sz, result, total);
 352                         goto err;
 353                 }
 354
 355                 total += result;
 356         } while (msg_data_left(&msg));
 357
 358         if (usbip_dbg_flag_xmit) {
 359                 if (!in_interrupt())
 360                         pr_debug("%-10s:", current->comm);
 361                 else
 362                         pr_debug("interrupt  :");
 363
 364                 pr_debug("receiving....\n");
 365                 usbip_dump_buffer(buf, size);
 366                 pr_debug("received, osize %d ret %d size %zd total %d\n",
 367                          size, result, msg_data_left(&msg), total);
 368         }
 369
 370         return total;
 371
 372 err:
 373         return result;
 374 }
 375 EXPORT_SYMBOL_GPL(usbip_recv);
 376
 377 /* there may be more cases to tweak the flags. */
 378 static unsigned int tweak_transfer_flags(unsigned int flags)
 379 {
 380         flags &= ~URB_NO_TRANSFER_DMA_MAP;
 381         return flags;
 382 }
 383
 384 static void usbip_pack_cmd_submit(struct usbip_header *pdu, struct urb *urb,
 385                                   int pack)
 386 {
 387         struct usbip_header_cmd_submit *spdu = &pdu->u.cmd_submit;
 388
 389         /*
 390          * Some members are not still implemented in usbip. I hope this issue
 391          * will be discussed when usbip is ported to other operating systems.
 392          */
 393         if (pack) {
 394                 spdu->transfer_flags =
 395                         tweak_transfer_flags(urb->transfer_flags);
 396                 spdu->transfer_buffer_length    = urb->transfer_buffer_length;
 397                 spdu->start_frame               = urb->start_frame;
 398                 spdu->number_of_packets         = urb->number_of_packets;
 399                 spdu->interval                  = urb->interval;
 400         } else  {
 401                 urb->transfer_flags         = spdu->transfer_flags;
 402                 urb->transfer_buffer_length = spdu->transfer_buffer_length;
 403                 urb->start_frame            = spdu->start_frame;
 404                 urb->number_of_packets      = spdu->number_of_packets;
 405                 urb->interval               = spdu->interval;
 406         }
 407 }
 408
 409 static void usbip_pack_ret_submit(struct usbip_header *pdu, struct urb *urb,
 410                                   int pack)
 411 {
 412         struct usbip_header_ret_submit *rpdu = &pdu->u.ret_submit;
 413
 414         if (pack) {
 415                 rpdu->status            = urb->status;
 416                 rpdu->actual_length     = urb->actual_length;
 417                 rpdu->start_frame       = urb->start_frame;
 418                 rpdu->number_of_packets = urb->number_of_packets;
 419                 rpdu->error_count       = urb->error_count;
 420         } else {
 421                 urb->status             = rpdu->status;
 422                 urb->actual_length      = rpdu->actual_length;
 423                 urb->start_frame        = rpdu->start_frame;
 424                 urb->number_of_packets = rpdu->number_of_packets;
 425                 urb->error_count        = rpdu->error_count;
 426         }
 427 }
 428
 429 void usbip_pack_pdu(struct usbip_header *pdu, struct urb *urb, int cmd,
 430                     int pack)
 431 {
 432         switch (cmd) {
 433         case USBIP_CMD_SUBMIT:
 434                 usbip_pack_cmd_submit(pdu, urb, pack);
 435                 break;
 436         case USBIP_RET_SUBMIT:
 437                 usbip_pack_ret_submit(pdu, urb, pack);
 438                 break;
 439         default:
 440                 /* NOT REACHED */
 441                 pr_err("unknown command\n");
 442                 break;
 443         }
 444 }
 445 EXPORT_SYMBOL_GPL(usbip_pack_pdu);
 446
 447 static void correct_endian_basic(struct usbip_header_basic *base, int send)
 448 {
 449         if (send) {
 450                 base->command   = cpu_to_be32(base->command);
 451                 base->seqnum    = cpu_to_be32(base->seqnum);
 452                 base->devid     = cpu_to_be32(base->devid);
 453                 base->direction = cpu_to_be32(base->direction);
 454                 base->ep        = cpu_to_be32(base->ep);
 455         } else {
 456                 base->command   = be32_to_cpu(base->command);
 457                 base->seqnum    = be32_to_cpu(base->seqnum);
 458                 base->devid     = be32_to_cpu(base->devid);
 459                 base->direction = be32_to_cpu(base->direction);
 460                 base->ep        = be32_to_cpu(base->ep);
 461         }
 462 }
 463
 464 static void correct_endian_cmd_submit(struct usbip_header_cmd_submit *pdu,
 465                                       int send)
 466 {
 467         if (send) {
 468                 pdu->transfer_flags = cpu_to_be32(pdu->transfer_flags);
 469
 470                 cpu_to_be32s(&pdu->transfer_buffer_length);
 471                 cpu_to_be32s(&pdu->start_frame);
 472                 cpu_to_be32s(&pdu->number_of_packets);
 473                 cpu_to_be32s(&pdu->interval);
 474         } else {
 475                 pdu->transfer_flags = be32_to_cpu(pdu->transfer_flags);
 476
 477                 be32_to_cpus(&pdu->transfer_buffer_length);
 478                 be32_to_cpus(&pdu->start_frame);
 479                 be32_to_cpus(&pdu->number_of_packets);
 480                 be32_to_cpus(&pdu->interval);
 481         }
 482 }
 483
 484 static void correct_endian_ret_submit(struct usbip_header_ret_submit *pdu,
 485                                       int send)
 486 {
 487         if (send) {
 488                 cpu_to_be32s(&pdu->status);
 489                 cpu_to_be32s(&pdu->actual_length);
 490                 cpu_to_be32s(&pdu->start_frame);
 491                 cpu_to_be32s(&pdu->number_of_packets);
 492                 cpu_to_be32s(&pdu->error_count);
 493         } else {
 494                 be32_to_cpus(&pdu->status);
 495                 be32_to_cpus(&pdu->actual_length);
 496                 be32_to_cpus(&pdu->start_frame);
 497                 be32_to_cpus(&pdu->number_of_packets);
 498                 be32_to_cpus(&pdu->error_count);
 499         }
 500 }
 501
 502 static void correct_endian_cmd_unlink(struct usbip_header_cmd_unlink *pdu,
 503                                       int send)
 504 {
 505         if (send)
 506                 pdu->seqnum = cpu_to_be32(pdu->seqnum);
 507         else
 508                 pdu->seqnum = be32_to_cpu(pdu->seqnum);
 509 }
 510
 511 static void correct_endian_ret_unlink(struct usbip_header_ret_unlink *pdu,
 512                                       int send)
 513 {
 514         if (send)
 515                 cpu_to_be32s(&pdu->status);
 516         else
 517                 be32_to_cpus(&pdu->status);
 518 }
 519
 520 void usbip_header_correct_endian(struct usbip_header *pdu, int send)
 521 {
 522         __u32 cmd = 0;
 523
 524         if (send)
 525                 cmd = pdu->base.command;
 526
 527         correct_endian_basic(&pdu->base, send);
 528
 529         if (!send)
 530                 cmd = pdu->base.command;
 531
 532         switch (cmd) {
 533         case USBIP_CMD_SUBMIT:
 534                 correct_endian_cmd_submit(&pdu->u.cmd_submit, send);
 535                 break;
 536         case USBIP_RET_SUBMIT:
 537                 correct_endian_ret_submit(&pdu->u.ret_submit, send);
 538                 break;
 539         case USBIP_CMD_UNLINK:
 540                 correct_endian_cmd_unlink(&pdu->u.cmd_unlink, send);
 541                 break;
 542         case USBIP_RET_UNLINK:
 543                 correct_endian_ret_unlink(&pdu->u.ret_unlink, send);
 544                 break;
 545         default:
 546                 /* NOT REACHED */
 547                 pr_err("unknown command\n");
 548                 break;
 549         }
 550 }
 551 EXPORT_SYMBOL_GPL(usbip_header_correct_endian);
 552
 553 static void usbip_iso_packet_correct_endian(
 554                 struct usbip_iso_packet_descriptor *iso, int send)
 555 {
 556         /* does not need all members. but copy all simply. */
 557         if (send) {
 558                 iso->offset     = cpu_to_be32(iso->offset);
 559                 iso->length     = cpu_to_be32(iso->length);
 560                 iso->status     = cpu_to_be32(iso->status);
 561                 iso->actual_length = cpu_to_be32(iso->actual_length);
 562         } else {
 563                 iso->offset     = be32_to_cpu(iso->offset);
 564                 iso->length     = be32_to_cpu(iso->length);
 565                 iso->status     = be32_to_cpu(iso->status);
 566                 iso->actual_length = be32_to_cpu(iso->actual_length);
 567         }
 568 }
 569
 570 static void usbip_pack_iso(struct usbip_iso_packet_descriptor *iso,
 571                            struct usb_iso_packet_descriptor *uiso, int pack)
 572 {
 573         if (pack) {
 574                 iso->offset             = uiso->offset;
 575                 iso->length             = uiso->length;
 576                 iso->status             = uiso->status;
 577                 iso->actual_length      = uiso->actual_length;
 578         } else {
 579                 uiso->offset            = iso->offset;
 580                 uiso->length            = iso->length;
 581                 uiso->status            = iso->status;
 582                 uiso->actual_length     = iso->actual_length;
 583         }
 584 }
 585
 586 /* must free buffer */
 587 struct usbip_iso_packet_descriptor*
 588 usbip_alloc_iso_desc_pdu(struct urb *urb, ssize_t *bufflen)
 589 {
 590         struct usbip_iso_packet_descriptor *iso;
 591         int np = urb->number_of_packets;
 592         ssize_t size = np * sizeof(*iso);
 593         int i;
 594
 595         iso = kzalloc(size, GFP_KERNEL);
 596         if (!iso)
 597                 return NULL;
 598
 599         for (i = 0; i < np; i++) {
 600                 usbip_pack_iso(&iso[i], &urb->iso_frame_desc[i], 1);
 601                 usbip_iso_packet_correct_endian(&iso[i], 1);
 602         }
 603
 604         *bufflen = size;
 605
 606         return iso;
 607 }
 608 EXPORT_SYMBOL_GPL(usbip_alloc_iso_desc_pdu);
 609
 610 /* some members of urb must be substituted before. */
 611 int usbip_recv_iso(struct usbip_device *ud, struct urb *urb)
 612 {
 613         void *buff;
 614         struct usbip_iso_packet_descriptor *iso;
 615         int np = urb->number_of_packets;
 616         int size = np * sizeof(*iso);
 617         int i;
 618         int ret;
 619         int total_length = 0;
 620
 621         if (!usb_pipeisoc(urb->pipe))
 622                 return 0;
 623
 624         /* my Bluetooth dongle gets ISO URBs which are np = 0 */
 625         if (np == 0)
 626                 return 0;
 627
 628         buff = kzalloc(size, GFP_KERNEL);
 629         if (!buff)
 630                 return -ENOMEM;
 631
 632         ret = usbip_recv(ud->tcp_socket, buff, size);
 633         if (ret != size) {
 634                 dev_err(&urb->dev->dev, "recv iso_frame_descriptor, %d\n",
 635                         ret);
 636                 kfree(buff);
 637
 638                 if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
 639                         usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
 640                 else
 641                         usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 642
 643                 return -EPIPE;
 644         }
 645
 646         iso = (struct usbip_iso_packet_descriptor *) buff;
 647         for (i = 0; i < np; i++) {
 648                 usbip_iso_packet_correct_endian(&iso[i], 0);
 649                 usbip_pack_iso(&iso[i], &urb->iso_frame_desc[i], 0);
 650                 total_length += urb->iso_frame_desc[i].actual_length;
 651         }
 652
 653         kfree(buff);
 654
 655         if (total_length != urb->actual_length) {
 656                 dev_err(&urb->dev->dev,
 657                         "total length of iso packets %d not equal to actual length of buffer %d\n",
 658                         total_length, urb->actual_length);
 659
 660                 if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
 661                         usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
 662                 else
 663                         usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 664
 665                 return -EPIPE;
 666         }
 667
 668         return ret;
 669 }
 670 EXPORT_SYMBOL_GPL(usbip_recv_iso);
 671
 672 /*
 673  * This functions restores the padding which was removed for optimizing
 674  * the bandwidth during transfer over tcp/ip
 675  *
 676  * buffer and iso packets need to be stored and be in propeper endian in urb
 677  * before calling this function
 678  */
 679 void usbip_pad_iso(struct usbip_device *ud, struct urb *urb)
 680 {
 681         int np = urb->number_of_packets;
 682         int i;
 683         int actualoffset = urb->actual_length;
 684
 685         if (!usb_pipeisoc(urb->pipe))
 686                 return;
 687
 688         /* if no packets or length of data is 0, then nothing to unpack */
 689         if (np == 0 || urb->actual_length == 0)
 690                 return;
 691
 692         /*
 693          * if actual_length is transfer_buffer_length then no padding is
 694          * present.
 695          */
 696         if (urb->actual_length == urb->transfer_buffer_length)
 697                 return;
 698
 699         /*
 700          * loop over all packets from last to first (to prevent overwriting
 701          * memory when padding) and move them into the proper place
 702          */
 703         for (i = np-1; i > 0; i--) {
 704                 actualoffset -= urb->iso_frame_desc[i].actual_length;
 705                 memmove(urb->transfer_buffer + urb->iso_frame_desc[i].offset,
 706                         urb->transfer_buffer + actualoffset,
 707                         urb->iso_frame_desc[i].actual_length);
 708         }
 709 }
 710 EXPORT_SYMBOL_GPL(usbip_pad_iso);
 711
 712 /* some members of urb must be substituted before. */
 713 int usbip_recv_xbuff(struct usbip_device *ud, struct urb *urb)
 714 {
 715         int ret;
 716         int size;
 717
 718         if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC) {
 719                 /* the direction of urb must be OUT. */
 720                 if (usb_pipein(urb->pipe))
 721                         return 0;
 722
 723                 size = urb->transfer_buffer_length;
 724         } else {
 725                 /* the direction of urb must be IN. */
 726                 if (usb_pipeout(urb->pipe))
 727                         return 0;
 728
 729                 size = urb->actual_length;
 730         }
 731
 732         /* no need to recv xbuff */
 733         if (!(size > 0))
 734                 return 0;
 735
 736         if (size > urb->transfer_buffer_length) {
 737                 /* should not happen, probably malicious packet */
 738                 if (ud->side == USBIP_STUB) {
 739                         usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
 740                         return 0;
 741                 } else {
 742                         usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 743                         return -EPIPE;
 744                 }
 745         }
 746
 747         ret = usbip_recv(ud->tcp_socket, urb->transfer_buffer, size);
 748         if (ret != size) {
 749                 dev_err(&urb->dev->dev, "recv xbuf, %d\n", ret);
 750                 if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC) {
 751                         usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
 752                 } else {
 753                         usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 754                         return -EPIPE;
 755                 }
 756         }
 757
 758         return ret;
 759 }
 760 EXPORT_SYMBOL_GPL(usbip_recv_xbuff);
 761
 762 static int __init usbip_core_init(void)
 763 {
 764         int ret;
 765
 766         pr_info(DRIVER_DESC " v" USBIP_VERSION "\n");
 767         ret = usbip_init_eh();
 768         if (ret)
 769                 return ret;
 770
 771         return 0;
 772 }
 773
 774 static void __exit usbip_core_exit(void)
 775 {
 776         usbip_finish_eh();
 777         return;
 778 }
 779
 780 module_init(usbip_core_init);
 781 module_exit(usbip_core_exit);
 782
 783 MODULE_AUTHOR(DRIVER_AUTHOR);
 784 MODULE_DESCRIPTION(DRIVER_DESC);
 785 MODULE_LICENSE("GPL");
 786 MODULE_VERSION(USBIP_VERSION);