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