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 hub ttport %d\n", 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 %s, bus %s\n", dev_name(&udev->parent->dev),
 142                 udev->bus->bus_name);
 143
 144         dev_dbg(dev, "have_langid %d, string_langid %d\n",
 145                 udev->have_langid, udev->string_langid);
 146
 147         dev_dbg(dev, "maxchild %d\n", udev->maxchild);
 148 }
 149
 150 static void usbip_dump_request_type(__u8 rt)
 151 {
 152         switch (rt & USB_RECIP_MASK) {
 153         case USB_RECIP_DEVICE:
 154                 pr_debug("DEVICE");
 155                 break;
 156         case USB_RECIP_INTERFACE:
 157                 pr_debug("INTERF");
 158                 break;
 159         case USB_RECIP_ENDPOINT:
 160                 pr_debug("ENDPOI");
 161                 break;
 162         case USB_RECIP_OTHER:
 163                 pr_debug("OTHER ");
 164                 break;
 165         default:
 166                 pr_debug("------");
 167                 break;
 168         }
 169 }
 170
 171 static void usbip_dump_usb_ctrlrequest(struct usb_ctrlrequest *cmd)
 172 {
 173         if (!cmd) {
 174                 pr_debug("       : null pointer\n");
 175                 return;
 176         }
 177
 178         pr_debug("       ");
 179         pr_debug("bRequestType(%02X) bRequest(%02X) wValue(%04X) wIndex(%04X) wLength(%04X) ",
 180                  cmd->bRequestType, cmd->bRequest,
 181                  cmd->wValue, cmd->wIndex, cmd->wLength);
 182         pr_debug("\n       ");
 183
 184         if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD) {
 185                 pr_debug("STANDARD ");
 186                 switch (cmd->bRequest) {
 187                 case USB_REQ_GET_STATUS:
 188                         pr_debug("GET_STATUS\n");
 189                         break;
 190                 case USB_REQ_CLEAR_FEATURE:
 191                         pr_debug("CLEAR_FEAT\n");
 192                         break;
 193                 case USB_REQ_SET_FEATURE:
 194                         pr_debug("SET_FEAT\n");
 195                         break;
 196                 case USB_REQ_SET_ADDRESS:
 197                         pr_debug("SET_ADDRRS\n");
 198                         break;
 199                 case USB_REQ_GET_DESCRIPTOR:
 200                         pr_debug("GET_DESCRI\n");
 201                         break;
 202                 case USB_REQ_SET_DESCRIPTOR:
 203                         pr_debug("SET_DESCRI\n");
 204                         break;
 205                 case USB_REQ_GET_CONFIGURATION:
 206                         pr_debug("GET_CONFIG\n");
 207                         break;
 208                 case USB_REQ_SET_CONFIGURATION:
 209                         pr_debug("SET_CONFIG\n");
 210                         break;
 211                 case USB_REQ_GET_INTERFACE:
 212                         pr_debug("GET_INTERF\n");
 213                         break;
 214                 case USB_REQ_SET_INTERFACE:
 215                         pr_debug("SET_INTERF\n");
 216                         break;
 217                 case USB_REQ_SYNCH_FRAME:
 218                         pr_debug("SYNC_FRAME\n");
 219                         break;
 220                 default:
 221                         pr_debug("REQ(%02X)\n", cmd->bRequest);
 222                         break;
 223                 }
 224                 usbip_dump_request_type(cmd->bRequestType);
 225         } else if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_CLASS) {
 226                 pr_debug("CLASS\n");
 227         } else if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_VENDOR) {
 228                 pr_debug("VENDOR\n");
 229         } else if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_RESERVED) {
 230                 pr_debug("RESERVED\n");
 231         }
 232 }
 233
 234 void usbip_dump_urb(struct urb *urb)
 235 {
 236         struct device *dev;
 237
 238         if (!urb) {
 239                 pr_debug("urb: null pointer!!\n");
 240                 return;
 241         }
 242
 243         if (!urb->dev) {
 244                 pr_debug("urb->dev: null pointer!!\n");
 245                 return;
 246         }
 247
 248         dev = &urb->dev->dev;
 249
 250         usbip_dump_usb_device(urb->dev);
 251
 252         dev_dbg(dev, "   pipe                  :%08x ", urb->pipe);
 253
 254         usbip_dump_pipe(urb->pipe);
 255
 256         dev_dbg(dev, "   status                :%d\n", urb->status);
 257         dev_dbg(dev, "   transfer_flags        :%08X\n", urb->transfer_flags);
 258         dev_dbg(dev, "   transfer_buffer_length:%d\n",
 259                                                 urb->transfer_buffer_length);
 260         dev_dbg(dev, "   actual_length         :%d\n", urb->actual_length);
 261
 262         if (urb->setup_packet && usb_pipetype(urb->pipe) == PIPE_CONTROL)
 263                 usbip_dump_usb_ctrlrequest(
 264                         (struct usb_ctrlrequest *)urb->setup_packet);
 265
 266         dev_dbg(dev, "   start_frame           :%d\n", urb->start_frame);
 267         dev_dbg(dev, "   number_of_packets     :%d\n", urb->number_of_packets);
 268         dev_dbg(dev, "   interval              :%d\n", urb->interval);
 269         dev_dbg(dev, "   error_count           :%d\n", urb->error_count);
 270 }
 271 EXPORT_SYMBOL_GPL(usbip_dump_urb);
 272
 273 void usbip_dump_header(struct usbip_header *pdu)
 274 {
 275         pr_debug("BASE: cmd %u seq %u devid %u dir %u ep %u\n",
 276                  pdu->base.command,
 277                  pdu->base.seqnum,
 278                  pdu->base.devid,
 279                  pdu->base.direction,
 280                  pdu->base.ep);
 281
 282         switch (pdu->base.command) {
 283         case USBIP_CMD_SUBMIT:
 284                 pr_debug("USBIP_CMD_SUBMIT: x_flags %u x_len %u sf %u #p %d iv %d\n",
 285                          pdu->u.cmd_submit.transfer_flags,
 286                          pdu->u.cmd_submit.transfer_buffer_length,
 287                          pdu->u.cmd_submit.start_frame,
 288                          pdu->u.cmd_submit.number_of_packets,
 289                          pdu->u.cmd_submit.interval);
 290                 break;
 291         case USBIP_CMD_UNLINK:
 292                 pr_debug("USBIP_CMD_UNLINK: seq %u\n",
 293                          pdu->u.cmd_unlink.seqnum);
 294                 break;
 295         case USBIP_RET_SUBMIT:
 296                 pr_debug("USBIP_RET_SUBMIT: st %d al %u sf %d #p %d ec %d\n",
 297                          pdu->u.ret_submit.status,
 298                          pdu->u.ret_submit.actual_length,
 299                          pdu->u.ret_submit.start_frame,
 300                          pdu->u.ret_submit.number_of_packets,
 301                          pdu->u.ret_submit.error_count);
 302                 break;
 303         case USBIP_RET_UNLINK:
 304                 pr_debug("USBIP_RET_UNLINK: status %d\n",
 305                          pdu->u.ret_unlink.status);
 306                 break;
 307         default:
 308                 /* NOT REACHED */
 309                 pr_err("unknown command\n");
 310                 break;
 311         }
 312 }
 313 EXPORT_SYMBOL_GPL(usbip_dump_header);
 314
 315 /* Receive data over TCP/IP. */
 316 int usbip_recv(struct socket *sock, void *buf, int size)
 317 {
 318         int result;
 319         struct msghdr msg;
 320         struct kvec iov;
 321         int total = 0;
 322
 323         /* for blocks of if (usbip_dbg_flag_xmit) */
 324         char *bp = buf;
 325         int osize = size;
 326
 327         if (!sock || !buf || !size)
 328                 return -EINVAL;
 329
 330         usbip_dbg_xmit("enter\n");
 331
 332         do {
 333                 sock->sk->sk_allocation = GFP_NOIO;
 334                 iov.iov_base    = buf;
 335                 iov.iov_len     = size;
 336                 msg.msg_name    = NULL;
 337                 msg.msg_namelen = 0;
 338                 msg.msg_control = NULL;
 339                 msg.msg_controllen = 0;
 340                 msg.msg_flags      = MSG_NOSIGNAL;
 341
 342                 result = kernel_recvmsg(sock, &msg, &iov, 1, size, MSG_WAITALL);
 343                 if (result <= 0)
 344                         goto err;
 345
 346                 size -= result;
 347                 buf += result;
 348                 total += result;
 349         } while (size > 0);
 350
 351         if (usbip_dbg_flag_xmit) {
 352                 if (!in_interrupt())
 353                         pr_debug("%-10s:", current->comm);
 354                 else
 355                         pr_debug("interrupt  :");
 356
 357                 pr_debug("receiving....\n");
 358                 usbip_dump_buffer(bp, osize);
 359                 pr_debug("received, osize %d ret %d size %d total %d\n",
 360                          osize, result, size, total);
 361         }
 362
 363         return total;
 364
 365 err:
 366         return result;
 367 }
 368 EXPORT_SYMBOL_GPL(usbip_recv);
 369
 370 /* there may be more cases to tweak the flags. */
 371 static unsigned int tweak_transfer_flags(unsigned int flags)
 372 {
 373         flags &= ~URB_NO_TRANSFER_DMA_MAP;
 374         return flags;
 375 }
 376
 377 static void usbip_pack_cmd_submit(struct usbip_header *pdu, struct urb *urb,
 378                                   int pack)
 379 {
 380         struct usbip_header_cmd_submit *spdu = &pdu->u.cmd_submit;
 381
 382         /*
 383          * Some members are not still implemented in usbip. I hope this issue
 384          * will be discussed when usbip is ported to other operating systems.
 385          */
 386         if (pack) {
 387                 spdu->transfer_flags =
 388                         tweak_transfer_flags(urb->transfer_flags);
 389                 spdu->transfer_buffer_length    = urb->transfer_buffer_length;
 390                 spdu->start_frame               = urb->start_frame;
 391                 spdu->number_of_packets         = urb->number_of_packets;
 392                 spdu->interval                  = urb->interval;
 393         } else  {
 394                 urb->transfer_flags         = spdu->transfer_flags;
 395                 urb->transfer_buffer_length = spdu->transfer_buffer_length;
 396                 urb->start_frame            = spdu->start_frame;
 397                 urb->number_of_packets      = spdu->number_of_packets;
 398                 urb->interval               = spdu->interval;
 399         }
 400 }
 401
 402 static void usbip_pack_ret_submit(struct usbip_header *pdu, struct urb *urb,
 403                                   int pack)
 404 {
 405         struct usbip_header_ret_submit *rpdu = &pdu->u.ret_submit;
 406
 407         if (pack) {
 408                 rpdu->status            = urb->status;
 409                 rpdu->actual_length     = urb->actual_length;
 410                 rpdu->start_frame       = urb->start_frame;
 411                 rpdu->number_of_packets = urb->number_of_packets;
 412                 rpdu->error_count       = urb->error_count;
 413         } else {
 414                 urb->status             = rpdu->status;
 415                 urb->actual_length      = rpdu->actual_length;
 416                 urb->start_frame        = rpdu->start_frame;
 417                 urb->number_of_packets = rpdu->number_of_packets;
 418                 urb->error_count        = rpdu->error_count;
 419         }
 420 }
 421
 422 void usbip_pack_pdu(struct usbip_header *pdu, struct urb *urb, int cmd,
 423                     int pack)
 424 {
 425         switch (cmd) {
 426         case USBIP_CMD_SUBMIT:
 427                 usbip_pack_cmd_submit(pdu, urb, pack);
 428                 break;
 429         case USBIP_RET_SUBMIT:
 430                 usbip_pack_ret_submit(pdu, urb, pack);
 431                 break;
 432         default:
 433                 /* NOT REACHED */
 434                 pr_err("unknown command\n");
 435                 break;
 436         }
 437 }
 438 EXPORT_SYMBOL_GPL(usbip_pack_pdu);
 439
 440 static void correct_endian_basic(struct usbip_header_basic *base, int send)
 441 {
 442         if (send) {
 443                 base->command   = cpu_to_be32(base->command);
 444                 base->seqnum    = cpu_to_be32(base->seqnum);
 445                 base->devid     = cpu_to_be32(base->devid);
 446                 base->direction = cpu_to_be32(base->direction);
 447                 base->ep        = cpu_to_be32(base->ep);
 448         } else {
 449                 base->command   = be32_to_cpu(base->command);
 450                 base->seqnum    = be32_to_cpu(base->seqnum);
 451                 base->devid     = be32_to_cpu(base->devid);
 452                 base->direction = be32_to_cpu(base->direction);
 453                 base->ep        = be32_to_cpu(base->ep);
 454         }
 455 }
 456
 457 static void correct_endian_cmd_submit(struct usbip_header_cmd_submit *pdu,
 458                                       int send)
 459 {
 460         if (send) {
 461                 pdu->transfer_flags = cpu_to_be32(pdu->transfer_flags);
 462
 463                 cpu_to_be32s(&pdu->transfer_buffer_length);
 464                 cpu_to_be32s(&pdu->start_frame);
 465                 cpu_to_be32s(&pdu->number_of_packets);
 466                 cpu_to_be32s(&pdu->interval);
 467         } else {
 468                 pdu->transfer_flags = be32_to_cpu(pdu->transfer_flags);
 469
 470                 be32_to_cpus(&pdu->transfer_buffer_length);
 471                 be32_to_cpus(&pdu->start_frame);
 472                 be32_to_cpus(&pdu->number_of_packets);
 473                 be32_to_cpus(&pdu->interval);
 474         }
 475 }
 476
 477 static void correct_endian_ret_submit(struct usbip_header_ret_submit *pdu,
 478                                       int send)
 479 {
 480         if (send) {
 481                 cpu_to_be32s(&pdu->status);
 482                 cpu_to_be32s(&pdu->actual_length);
 483                 cpu_to_be32s(&pdu->start_frame);
 484                 cpu_to_be32s(&pdu->number_of_packets);
 485                 cpu_to_be32s(&pdu->error_count);
 486         } else {
 487                 be32_to_cpus(&pdu->status);
 488                 be32_to_cpus(&pdu->actual_length);
 489                 be32_to_cpus(&pdu->start_frame);
 490                 be32_to_cpus(&pdu->number_of_packets);
 491                 be32_to_cpus(&pdu->error_count);
 492         }
 493 }
 494
 495 static void correct_endian_cmd_unlink(struct usbip_header_cmd_unlink *pdu,
 496                                       int send)
 497 {
 498         if (send)
 499                 pdu->seqnum = cpu_to_be32(pdu->seqnum);
 500         else
 501                 pdu->seqnum = be32_to_cpu(pdu->seqnum);
 502 }
 503
 504 static void correct_endian_ret_unlink(struct usbip_header_ret_unlink *pdu,
 505                                       int send)
 506 {
 507         if (send)
 508                 cpu_to_be32s(&pdu->status);
 509         else
 510                 be32_to_cpus(&pdu->status);
 511 }
 512
 513 void usbip_header_correct_endian(struct usbip_header *pdu, int send)
 514 {
 515         __u32 cmd = 0;
 516
 517         if (send)
 518                 cmd = pdu->base.command;
 519
 520         correct_endian_basic(&pdu->base, send);
 521
 522         if (!send)
 523                 cmd = pdu->base.command;
 524
 525         switch (cmd) {
 526         case USBIP_CMD_SUBMIT:
 527                 correct_endian_cmd_submit(&pdu->u.cmd_submit, send);
 528                 break;
 529         case USBIP_RET_SUBMIT:
 530                 correct_endian_ret_submit(&pdu->u.ret_submit, send);
 531                 break;
 532         case USBIP_CMD_UNLINK:
 533                 correct_endian_cmd_unlink(&pdu->u.cmd_unlink, send);
 534                 break;
 535         case USBIP_RET_UNLINK:
 536                 correct_endian_ret_unlink(&pdu->u.ret_unlink, send);
 537                 break;
 538         default:
 539                 /* NOT REACHED */
 540                 pr_err("unknown command\n");
 541                 break;
 542         }
 543 }
 544 EXPORT_SYMBOL_GPL(usbip_header_correct_endian);
 545
 546 static void usbip_iso_packet_correct_endian(
 547                 struct usbip_iso_packet_descriptor *iso, int send)
 548 {
 549         /* does not need all members. but copy all simply. */
 550         if (send) {
 551                 iso->offset     = cpu_to_be32(iso->offset);
 552                 iso->length     = cpu_to_be32(iso->length);
 553                 iso->status     = cpu_to_be32(iso->status);
 554                 iso->actual_length = cpu_to_be32(iso->actual_length);
 555         } else {
 556                 iso->offset     = be32_to_cpu(iso->offset);
 557                 iso->length     = be32_to_cpu(iso->length);
 558                 iso->status     = be32_to_cpu(iso->status);
 559                 iso->actual_length = be32_to_cpu(iso->actual_length);
 560         }
 561 }
 562
 563 static void usbip_pack_iso(struct usbip_iso_packet_descriptor *iso,
 564                            struct usb_iso_packet_descriptor *uiso, int pack)
 565 {
 566         if (pack) {
 567                 iso->offset             = uiso->offset;
 568                 iso->length             = uiso->length;
 569                 iso->status             = uiso->status;
 570                 iso->actual_length      = uiso->actual_length;
 571         } else {
 572                 uiso->offset            = iso->offset;
 573                 uiso->length            = iso->length;
 574                 uiso->status            = iso->status;
 575                 uiso->actual_length     = iso->actual_length;
 576         }
 577 }
 578
 579 /* must free buffer */
 580 struct usbip_iso_packet_descriptor*
 581 usbip_alloc_iso_desc_pdu(struct urb *urb, ssize_t *bufflen)
 582 {
 583         struct usbip_iso_packet_descriptor *iso;
 584         int np = urb->number_of_packets;
 585         ssize_t size = np * sizeof(*iso);
 586         int i;
 587
 588         iso = kzalloc(size, GFP_KERNEL);
 589         if (!iso)
 590                 return NULL;
 591
 592         for (i = 0; i < np; i++) {
 593                 usbip_pack_iso(&iso[i], &urb->iso_frame_desc[i], 1);
 594                 usbip_iso_packet_correct_endian(&iso[i], 1);
 595         }
 596
 597         *bufflen = size;
 598
 599         return iso;
 600 }
 601 EXPORT_SYMBOL_GPL(usbip_alloc_iso_desc_pdu);
 602
 603 /* some members of urb must be substituted before. */
 604 int usbip_recv_iso(struct usbip_device *ud, struct urb *urb)
 605 {
 606         void *buff;
 607         struct usbip_iso_packet_descriptor *iso;
 608         int np = urb->number_of_packets;
 609         int size = np * sizeof(*iso);
 610         int i;
 611         int ret;
 612         int total_length = 0;
 613
 614         if (!usb_pipeisoc(urb->pipe))
 615                 return 0;
 616
 617         /* my Bluetooth dongle gets ISO URBs which are np = 0 */
 618         if (np == 0)
 619                 return 0;
 620
 621         buff = kzalloc(size, GFP_KERNEL);
 622         if (!buff)
 623                 return -ENOMEM;
 624
 625         ret = usbip_recv(ud->tcp_socket, buff, size);
 626         if (ret != size) {
 627                 dev_err(&urb->dev->dev, "recv iso_frame_descriptor, %d\n",
 628                         ret);
 629                 kfree(buff);
 630
 631                 if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
 632                         usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
 633                 else
 634                         usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 635
 636                 return -EPIPE;
 637         }
 638
 639         iso = (struct usbip_iso_packet_descriptor *) buff;
 640         for (i = 0; i < np; i++) {
 641                 usbip_iso_packet_correct_endian(&iso[i], 0);
 642                 usbip_pack_iso(&iso[i], &urb->iso_frame_desc[i], 0);
 643                 total_length += urb->iso_frame_desc[i].actual_length;
 644         }
 645
 646         kfree(buff);
 647
 648         if (total_length != urb->actual_length) {
 649                 dev_err(&urb->dev->dev,
 650                         "total length of iso packets %d not equal to actual length of buffer %d\n",
 651                         total_length, urb->actual_length);
 652
 653                 if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
 654                         usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
 655                 else
 656                         usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 657
 658                 return -EPIPE;
 659         }
 660
 661         return ret;
 662 }
 663 EXPORT_SYMBOL_GPL(usbip_recv_iso);
 664
 665 /*
 666  * This functions restores the padding which was removed for optimizing
 667  * the bandwidth during transfer over tcp/ip
 668  *
 669  * buffer and iso packets need to be stored and be in propeper endian in urb
 670  * before calling this function
 671  */
 672 void usbip_pad_iso(struct usbip_device *ud, struct urb *urb)
 673 {
 674         int np = urb->number_of_packets;
 675         int i;
 676         int actualoffset = urb->actual_length;
 677
 678         if (!usb_pipeisoc(urb->pipe))
 679                 return;
 680
 681         /* if no packets or length of data is 0, then nothing to unpack */
 682         if (np == 0 || urb->actual_length == 0)
 683                 return;
 684
 685         /*
 686          * if actual_length is transfer_buffer_length then no padding is
 687          * present.
 688          */
 689         if (urb->actual_length == urb->transfer_buffer_length)
 690                 return;
 691
 692         /*
 693          * loop over all packets from last to first (to prevent overwritting
 694          * memory when padding) and move them into the proper place
 695          */
 696         for (i = np-1; i > 0; i--) {
 697                 actualoffset -= urb->iso_frame_desc[i].actual_length;
 698                 memmove(urb->transfer_buffer + urb->iso_frame_desc[i].offset,
 699                         urb->transfer_buffer + actualoffset,
 700                         urb->iso_frame_desc[i].actual_length);
 701         }
 702 }
 703 EXPORT_SYMBOL_GPL(usbip_pad_iso);
 704
 705 /* some members of urb must be substituted before. */
 706 int usbip_recv_xbuff(struct usbip_device *ud, struct urb *urb)
 707 {
 708         int ret;
 709         int size;
 710
 711         if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC) {
 712                 /* the direction of urb must be OUT. */
 713                 if (usb_pipein(urb->pipe))
 714                         return 0;
 715
 716                 size = urb->transfer_buffer_length;
 717         } else {
 718                 /* the direction of urb must be IN. */
 719                 if (usb_pipeout(urb->pipe))
 720                         return 0;
 721
 722                 size = urb->actual_length;
 723         }
 724
 725         /* no need to recv xbuff */
 726         if (!(size > 0))
 727                 return 0;
 728
 729         if (size > urb->transfer_buffer_length) {
 730                 /* should not happen, probably malicious packet */
 731                 if (ud->side == USBIP_STUB) {
 732                         usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
 733                         return 0;
 734                 } else {
 735                         usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 736                         return -EPIPE;
 737                 }
 738         }
 739
 740         ret = usbip_recv(ud->tcp_socket, urb->transfer_buffer, size);
 741         if (ret != size) {
 742                 dev_err(&urb->dev->dev, "recv xbuf, %d\n", ret);
 743                 if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC) {
 744                         usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
 745                 } else {
 746                         usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 747                         return -EPIPE;
 748                 }
 749         }
 750
 751         return ret;
 752 }
 753 EXPORT_SYMBOL_GPL(usbip_recv_xbuff);
 754
 755 static int __init usbip_core_init(void)
 756 {
 757         int ret;
 758
 759         pr_info(DRIVER_DESC " v" USBIP_VERSION "\n");
 760         ret = usbip_init_eh();
 761         if (ret)
 762                 return ret;
 763
 764         return 0;
 765 }
 766
 767 static void __exit usbip_core_exit(void)
 768 {
 769         usbip_finish_eh();
 770         return;
 771 }
 772
 773 module_init(usbip_core_init);
 774 module_exit(usbip_core_exit);
 775
 776 MODULE_AUTHOR(DRIVER_AUTHOR);
 777 MODULE_DESCRIPTION(DRIVER_DESC);
 778 MODULE_LICENSE("GPL");
 779 MODULE_VERSION(USBIP_VERSION);