drivers/usb/usbip/usbip_common.c

   1 /*
   2  * Copyright (C) 2003-2008 Takahiro Hirofuchi
   3  * Copyright (C) 2015-2016 Samsung Electronics
   4  *               Krzysztof Opasiak <[email protected]>
   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 <[email protected]>"
  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 msghdr msg;
 331         struct kvec iov;
 332         int total = 0;
 333
 334         /* for blocks of if (usbip_dbg_flag_xmit) */
 335         char *bp = buf;
 336         int osize = size;
 337
 338         usbip_dbg_xmit("enter\n");
 339
 340         if (!sock || !buf || !size) {
 341                 pr_err("invalid arg, sock %p buff %p size %d\n", sock, buf,
 342                        size);
 343                 return -EINVAL;
 344         }
 345
 346         do {
 347                 sock->sk->sk_allocation = GFP_NOIO;
 348                 iov.iov_base    = buf;
 349                 iov.iov_len     = size;
 350                 msg.msg_name    = NULL;
 351                 msg.msg_namelen = 0;
 352                 msg.msg_control = NULL;
 353                 msg.msg_controllen = 0;
 354                 msg.msg_flags      = MSG_NOSIGNAL;
 355
 356                 result = kernel_recvmsg(sock, &msg, &iov, 1, size, MSG_WAITALL);
 357                 if (result <= 0) {
 358                         pr_debug("receive sock %p buf %p size %u ret %d total %d\n",
 359                                  sock, buf, size, result, total);
 360                         goto err;
 361                 }
 362
 363                 size -= result;
 364                 buf += result;
 365                 total += result;
 366         } while (size > 0);
 367
 368         if (usbip_dbg_flag_xmit) {
 369                 if (!in_interrupt())
 370                         pr_debug("%-10s:", current->comm);
 371                 else
 372                         pr_debug("interrupt  :");
 373
 374                 pr_debug("receiving....\n");
 375                 usbip_dump_buffer(bp, osize);
 376                 pr_debug("received, osize %d ret %d size %d total %d\n",
 377                          osize, result, size, total);
 378         }
 379
 380         return total;
 381
 382 err:
 383         return result;
 384 }
 385 EXPORT_SYMBOL_GPL(usbip_recv);
 386
 387 /* there may be more cases to tweak the flags. */
 388 static unsigned int tweak_transfer_flags(unsigned int flags)
 389 {
 390         flags &= ~URB_NO_TRANSFER_DMA_MAP;
 391         return flags;
 392 }
 393
 394 static void usbip_pack_cmd_submit(struct usbip_header *pdu, struct urb *urb,
 395                                   int pack)
 396 {
 397         struct usbip_header_cmd_submit *spdu = &pdu->u.cmd_submit;
 398
 399         /*
 400          * Some members are not still implemented in usbip. I hope this issue
 401          * will be discussed when usbip is ported to other operating systems.
 402          */
 403         if (pack) {
 404                 spdu->transfer_flags =
 405                         tweak_transfer_flags(urb->transfer_flags);
 406                 spdu->transfer_buffer_length    = urb->transfer_buffer_length;
 407                 spdu->start_frame               = urb->start_frame;
 408                 spdu->number_of_packets         = urb->number_of_packets;
 409                 spdu->interval                  = urb->interval;
 410         } else  {
 411                 urb->transfer_flags         = spdu->transfer_flags;
 412                 urb->transfer_buffer_length = spdu->transfer_buffer_length;
 413                 urb->start_frame            = spdu->start_frame;
 414                 urb->number_of_packets      = spdu->number_of_packets;
 415                 urb->interval               = spdu->interval;
 416         }
 417 }
 418
 419 static void usbip_pack_ret_submit(struct usbip_header *pdu, struct urb *urb,
 420                                   int pack)
 421 {
 422         struct usbip_header_ret_submit *rpdu = &pdu->u.ret_submit;
 423
 424         if (pack) {
 425                 rpdu->status            = urb->status;
 426                 rpdu->actual_length     = urb->actual_length;
 427                 rpdu->start_frame       = urb->start_frame;
 428                 rpdu->number_of_packets = urb->number_of_packets;
 429                 rpdu->error_count       = urb->error_count;
 430         } else {
 431                 urb->status             = rpdu->status;
 432                 urb->actual_length      = rpdu->actual_length;
 433                 urb->start_frame        = rpdu->start_frame;
 434                 urb->number_of_packets = rpdu->number_of_packets;
 435                 urb->error_count        = rpdu->error_count;
 436         }
 437 }
 438
 439 void usbip_pack_pdu(struct usbip_header *pdu, struct urb *urb, int cmd,
 440                     int pack)
 441 {
 442         switch (cmd) {
 443         case USBIP_CMD_SUBMIT:
 444                 usbip_pack_cmd_submit(pdu, urb, pack);
 445                 break;
 446         case USBIP_RET_SUBMIT:
 447                 usbip_pack_ret_submit(pdu, urb, pack);
 448                 break;
 449         default:
 450                 /* NOT REACHED */
 451                 pr_err("unknown command\n");
 452                 break;
 453         }
 454 }
 455 EXPORT_SYMBOL_GPL(usbip_pack_pdu);
 456
 457 static void correct_endian_basic(struct usbip_header_basic *base, int send)
 458 {
 459         if (send) {
 460                 base->command   = cpu_to_be32(base->command);
 461                 base->seqnum    = cpu_to_be32(base->seqnum);
 462                 base->devid     = cpu_to_be32(base->devid);
 463                 base->direction = cpu_to_be32(base->direction);
 464                 base->ep        = cpu_to_be32(base->ep);
 465         } else {
 466                 base->command   = be32_to_cpu(base->command);
 467                 base->seqnum    = be32_to_cpu(base->seqnum);
 468                 base->devid     = be32_to_cpu(base->devid);
 469                 base->direction = be32_to_cpu(base->direction);
 470                 base->ep        = be32_to_cpu(base->ep);
 471         }
 472 }
 473
 474 static void correct_endian_cmd_submit(struct usbip_header_cmd_submit *pdu,
 475                                       int send)
 476 {
 477         if (send) {
 478                 pdu->transfer_flags = cpu_to_be32(pdu->transfer_flags);
 479
 480                 cpu_to_be32s(&pdu->transfer_buffer_length);
 481                 cpu_to_be32s(&pdu->start_frame);
 482                 cpu_to_be32s(&pdu->number_of_packets);
 483                 cpu_to_be32s(&pdu->interval);
 484         } else {
 485                 pdu->transfer_flags = be32_to_cpu(pdu->transfer_flags);
 486
 487                 be32_to_cpus(&pdu->transfer_buffer_length);
 488                 be32_to_cpus(&pdu->start_frame);
 489                 be32_to_cpus(&pdu->number_of_packets);
 490                 be32_to_cpus(&pdu->interval);
 491         }
 492 }
 493
 494 static void correct_endian_ret_submit(struct usbip_header_ret_submit *pdu,
 495                                       int send)
 496 {
 497         if (send) {
 498                 cpu_to_be32s(&pdu->status);
 499                 cpu_to_be32s(&pdu->actual_length);
 500                 cpu_to_be32s(&pdu->start_frame);
 501                 cpu_to_be32s(&pdu->number_of_packets);
 502                 cpu_to_be32s(&pdu->error_count);
 503         } else {
 504                 be32_to_cpus(&pdu->status);
 505                 be32_to_cpus(&pdu->actual_length);
 506                 be32_to_cpus(&pdu->start_frame);
 507                 be32_to_cpus(&pdu->number_of_packets);
 508                 be32_to_cpus(&pdu->error_count);
 509         }
 510 }
 511
 512 static void correct_endian_cmd_unlink(struct usbip_header_cmd_unlink *pdu,
 513                                       int send)
 514 {
 515         if (send)
 516                 pdu->seqnum = cpu_to_be32(pdu->seqnum);
 517         else
 518                 pdu->seqnum = be32_to_cpu(pdu->seqnum);
 519 }
 520
 521 static void correct_endian_ret_unlink(struct usbip_header_ret_unlink *pdu,
 522                                       int send)
 523 {
 524         if (send)
 525                 cpu_to_be32s(&pdu->status);
 526         else
 527                 be32_to_cpus(&pdu->status);
 528 }
 529
 530 void usbip_header_correct_endian(struct usbip_header *pdu, int send)
 531 {
 532         __u32 cmd = 0;
 533
 534         if (send)
 535                 cmd = pdu->base.command;
 536
 537         correct_endian_basic(&pdu->base, send);
 538
 539         if (!send)
 540                 cmd = pdu->base.command;
 541
 542         switch (cmd) {
 543         case USBIP_CMD_SUBMIT:
 544                 correct_endian_cmd_submit(&pdu->u.cmd_submit, send);
 545                 break;
 546         case USBIP_RET_SUBMIT:
 547                 correct_endian_ret_submit(&pdu->u.ret_submit, send);
 548                 break;
 549         case USBIP_CMD_UNLINK:
 550                 correct_endian_cmd_unlink(&pdu->u.cmd_unlink, send);
 551                 break;
 552         case USBIP_RET_UNLINK:
 553                 correct_endian_ret_unlink(&pdu->u.ret_unlink, send);
 554                 break;
 555         default:
 556                 /* NOT REACHED */
 557                 pr_err("unknown command\n");
 558                 break;
 559         }
 560 }
 561 EXPORT_SYMBOL_GPL(usbip_header_correct_endian);
 562
 563 static void usbip_iso_packet_correct_endian(
 564                 struct usbip_iso_packet_descriptor *iso, int send)
 565 {
 566         /* does not need all members. but copy all simply. */
 567         if (send) {
 568                 iso->offset     = cpu_to_be32(iso->offset);
 569                 iso->length     = cpu_to_be32(iso->length);
 570                 iso->status     = cpu_to_be32(iso->status);
 571                 iso->actual_length = cpu_to_be32(iso->actual_length);
 572         } else {
 573                 iso->offset     = be32_to_cpu(iso->offset);
 574                 iso->length     = be32_to_cpu(iso->length);
 575                 iso->status     = be32_to_cpu(iso->status);
 576                 iso->actual_length = be32_to_cpu(iso->actual_length);
 577         }
 578 }
 579
 580 static void usbip_pack_iso(struct usbip_iso_packet_descriptor *iso,
 581                            struct usb_iso_packet_descriptor *uiso, int pack)
 582 {
 583         if (pack) {
 584                 iso->offset             = uiso->offset;
 585                 iso->length             = uiso->length;
 586                 iso->status             = uiso->status;
 587                 iso->actual_length      = uiso->actual_length;
 588         } else {
 589                 uiso->offset            = iso->offset;
 590                 uiso->length            = iso->length;
 591                 uiso->status            = iso->status;
 592                 uiso->actual_length     = iso->actual_length;
 593         }
 594 }
 595
 596 /* must free buffer */
 597 struct usbip_iso_packet_descriptor*
 598 usbip_alloc_iso_desc_pdu(struct urb *urb, ssize_t *bufflen)
 599 {
 600         struct usbip_iso_packet_descriptor *iso;
 601         int np = urb->number_of_packets;
 602         ssize_t size = np * sizeof(*iso);
 603         int i;
 604
 605         iso = kzalloc(size, GFP_KERNEL);
 606         if (!iso)
 607                 return NULL;
 608
 609         for (i = 0; i < np; i++) {
 610                 usbip_pack_iso(&iso[i], &urb->iso_frame_desc[i], 1);
 611                 usbip_iso_packet_correct_endian(&iso[i], 1);
 612         }
 613
 614         *bufflen = size;
 615
 616         return iso;
 617 }
 618 EXPORT_SYMBOL_GPL(usbip_alloc_iso_desc_pdu);
 619
 620 /* some members of urb must be substituted before. */
 621 int usbip_recv_iso(struct usbip_device *ud, struct urb *urb)
 622 {
 623         void *buff;
 624         struct usbip_iso_packet_descriptor *iso;
 625         int np = urb->number_of_packets;
 626         int size = np * sizeof(*iso);
 627         int i;
 628         int ret;
 629         int total_length = 0;
 630
 631         if (!usb_pipeisoc(urb->pipe))
 632                 return 0;
 633
 634         /* my Bluetooth dongle gets ISO URBs which are np = 0 */
 635         if (np == 0)
 636                 return 0;
 637
 638         buff = kzalloc(size, GFP_KERNEL);
 639         if (!buff)
 640                 return -ENOMEM;
 641
 642         ret = usbip_recv(ud->tcp_socket, buff, size);
 643         if (ret != size) {
 644                 dev_err(&urb->dev->dev, "recv iso_frame_descriptor, %d\n",
 645                         ret);
 646                 kfree(buff);
 647
 648                 if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
 649                         usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
 650                 else
 651                         usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 652
 653                 return -EPIPE;
 654         }
 655
 656         iso = (struct usbip_iso_packet_descriptor *) buff;
 657         for (i = 0; i < np; i++) {
 658                 usbip_iso_packet_correct_endian(&iso[i], 0);
 659                 usbip_pack_iso(&iso[i], &urb->iso_frame_desc[i], 0);
 660                 total_length += urb->iso_frame_desc[i].actual_length;
 661         }
 662
 663         kfree(buff);
 664
 665         if (total_length != urb->actual_length) {
 666                 dev_err(&urb->dev->dev,
 667                         "total length of iso packets %d not equal to actual length of buffer %d\n",
 668                         total_length, urb->actual_length);
 669
 670                 if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
 671                         usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
 672                 else
 673                         usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 674
 675                 return -EPIPE;
 676         }
 677
 678         return ret;
 679 }
 680 EXPORT_SYMBOL_GPL(usbip_recv_iso);
 681
 682 /*
 683  * This functions restores the padding which was removed for optimizing
 684  * the bandwidth during transfer over tcp/ip
 685  *
 686  * buffer and iso packets need to be stored and be in propeper endian in urb
 687  * before calling this function
 688  */
 689 void usbip_pad_iso(struct usbip_device *ud, struct urb *urb)
 690 {
 691         int np = urb->number_of_packets;
 692         int i;
 693         int actualoffset = urb->actual_length;
 694
 695         if (!usb_pipeisoc(urb->pipe))
 696                 return;
 697
 698         /* if no packets or length of data is 0, then nothing to unpack */
 699         if (np == 0 || urb->actual_length == 0)
 700                 return;
 701
 702         /*
 703          * if actual_length is transfer_buffer_length then no padding is
 704          * present.
 705          */
 706         if (urb->actual_length == urb->transfer_buffer_length)
 707                 return;
 708
 709         /*
 710          * loop over all packets from last to first (to prevent overwritting
 711          * memory when padding) and move them into the proper place
 712          */
 713         for (i = np-1; i > 0; i--) {
 714                 actualoffset -= urb->iso_frame_desc[i].actual_length;
 715                 memmove(urb->transfer_buffer + urb->iso_frame_desc[i].offset,
 716                         urb->transfer_buffer + actualoffset,
 717                         urb->iso_frame_desc[i].actual_length);
 718         }
 719 }
 720 EXPORT_SYMBOL_GPL(usbip_pad_iso);
 721
 722 /* some members of urb must be substituted before. */
 723 int usbip_recv_xbuff(struct usbip_device *ud, struct urb *urb)
 724 {
 725         int ret;
 726         int size;
 727
 728         if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC) {
 729                 /* the direction of urb must be OUT. */
 730                 if (usb_pipein(urb->pipe))
 731                         return 0;
 732
 733                 size = urb->transfer_buffer_length;
 734         } else {
 735                 /* the direction of urb must be IN. */
 736                 if (usb_pipeout(urb->pipe))
 737                         return 0;
 738
 739                 size = urb->actual_length;
 740         }
 741
 742         /* no need to recv xbuff */
 743         if (!(size > 0))
 744                 return 0;
 745
 746         if (size > urb->transfer_buffer_length) {
 747                 /* should not happen, probably malicious packet */
 748                 if (ud->side == USBIP_STUB) {
 749                         usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
 750                         return 0;
 751                 } else {
 752                         usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 753                         return -EPIPE;
 754                 }
 755         }
 756
 757         ret = usbip_recv(ud->tcp_socket, urb->transfer_buffer, size);
 758         if (ret != size) {
 759                 dev_err(&urb->dev->dev, "recv xbuf, %d\n", ret);
 760                 if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC) {
 761                         usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
 762                 } else {
 763                         usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 764                         return -EPIPE;
 765                 }
 766         }
 767
 768         return ret;
 769 }
 770 EXPORT_SYMBOL_GPL(usbip_recv_xbuff);
 771
 772 static int __init usbip_core_init(void)
 773 {
 774         int ret;
 775
 776         pr_info(DRIVER_DESC " v" USBIP_VERSION "\n");
 777         ret = usbip_init_eh();
 778         if (ret)
 779                 return ret;
 780
 781         return 0;
 782 }
 783
 784 static void __exit usbip_core_exit(void)
 785 {
 786         usbip_finish_eh();
 787         return;
 788 }
 789
 790 module_init(usbip_core_init);
 791 module_exit(usbip_core_exit);
 792
 793 MODULE_AUTHOR(DRIVER_AUTHOR);
 794 MODULE_DESCRIPTION(DRIVER_DESC);
 795 MODULE_LICENSE("GPL");
 796 MODULE_VERSION(USBIP_VERSION);