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 kvec iov = {.iov_base = buf, .iov_len = size};
 320         struct msghdr msg = {.msg_flags = MSG_NOSIGNAL};
 321         int total = 0;
 322
 323         if (!sock || !buf || !size)
 324                 return -EINVAL;
 325
 326         iov_iter_kvec(&msg.msg_iter, READ|ITER_KVEC, &iov, 1, size);
 327
 328         usbip_dbg_xmit("enter\n");
 329
 330         do {
 331                 msg_data_left(&msg);
 332                 sock->sk->sk_allocation = GFP_NOIO;
 333
 334                 result = sock_recvmsg(sock, &msg, MSG_WAITALL);
 335                 if (result <= 0)
 336                         goto err;
 337
 338                 total += result;
 339         } while (msg_data_left(&msg));
 340
 341         if (usbip_dbg_flag_xmit) {
 342                 if (!in_interrupt())
 343                         pr_debug("%-10s:", current->comm);
 344                 else
 345                         pr_debug("interrupt  :");
 346
 347                 pr_debug("receiving....\n");
 348                 usbip_dump_buffer(buf, size);
 349                 pr_debug("received, osize %d ret %d size %zd total %d\n",
 350                          size, result, msg_data_left(&msg), total);
 351         }
 352
 353         return total;
 354
 355 err:
 356         return result;
 357 }
 358 EXPORT_SYMBOL_GPL(usbip_recv);
 359
 360 /* there may be more cases to tweak the flags. */
 361 static unsigned int tweak_transfer_flags(unsigned int flags)
 362 {
 363         flags &= ~URB_NO_TRANSFER_DMA_MAP;
 364         return flags;
 365 }
 366
 367 static void usbip_pack_cmd_submit(struct usbip_header *pdu, struct urb *urb,
 368                                   int pack)
 369 {
 370         struct usbip_header_cmd_submit *spdu = &pdu->u.cmd_submit;
 371
 372         /*
 373          * Some members are not still implemented in usbip. I hope this issue
 374          * will be discussed when usbip is ported to other operating systems.
 375          */
 376         if (pack) {
 377                 spdu->transfer_flags =
 378                         tweak_transfer_flags(urb->transfer_flags);
 379                 spdu->transfer_buffer_length    = urb->transfer_buffer_length;
 380                 spdu->start_frame               = urb->start_frame;
 381                 spdu->number_of_packets         = urb->number_of_packets;
 382                 spdu->interval                  = urb->interval;
 383         } else  {
 384                 urb->transfer_flags         = spdu->transfer_flags;
 385                 urb->transfer_buffer_length = spdu->transfer_buffer_length;
 386                 urb->start_frame            = spdu->start_frame;
 387                 urb->number_of_packets      = spdu->number_of_packets;
 388                 urb->interval               = spdu->interval;
 389         }
 390 }
 391
 392 static void usbip_pack_ret_submit(struct usbip_header *pdu, struct urb *urb,
 393                                   int pack)
 394 {
 395         struct usbip_header_ret_submit *rpdu = &pdu->u.ret_submit;
 396
 397         if (pack) {
 398                 rpdu->status            = urb->status;
 399                 rpdu->actual_length     = urb->actual_length;
 400                 rpdu->start_frame       = urb->start_frame;
 401                 rpdu->number_of_packets = urb->number_of_packets;
 402                 rpdu->error_count       = urb->error_count;
 403         } else {
 404                 urb->status             = rpdu->status;
 405                 urb->actual_length      = rpdu->actual_length;
 406                 urb->start_frame        = rpdu->start_frame;
 407                 urb->number_of_packets = rpdu->number_of_packets;
 408                 urb->error_count        = rpdu->error_count;
 409         }
 410 }
 411
 412 void usbip_pack_pdu(struct usbip_header *pdu, struct urb *urb, int cmd,
 413                     int pack)
 414 {
 415         switch (cmd) {
 416         case USBIP_CMD_SUBMIT:
 417                 usbip_pack_cmd_submit(pdu, urb, pack);
 418                 break;
 419         case USBIP_RET_SUBMIT:
 420                 usbip_pack_ret_submit(pdu, urb, pack);
 421                 break;
 422         default:
 423                 /* NOT REACHED */
 424                 pr_err("unknown command\n");
 425                 break;
 426         }
 427 }
 428 EXPORT_SYMBOL_GPL(usbip_pack_pdu);
 429
 430 static void correct_endian_basic(struct usbip_header_basic *base, int send)
 431 {
 432         if (send) {
 433                 base->command   = cpu_to_be32(base->command);
 434                 base->seqnum    = cpu_to_be32(base->seqnum);
 435                 base->devid     = cpu_to_be32(base->devid);
 436                 base->direction = cpu_to_be32(base->direction);
 437                 base->ep        = cpu_to_be32(base->ep);
 438         } else {
 439                 base->command   = be32_to_cpu(base->command);
 440                 base->seqnum    = be32_to_cpu(base->seqnum);
 441                 base->devid     = be32_to_cpu(base->devid);
 442                 base->direction = be32_to_cpu(base->direction);
 443                 base->ep        = be32_to_cpu(base->ep);
 444         }
 445 }
 446
 447 static void correct_endian_cmd_submit(struct usbip_header_cmd_submit *pdu,
 448                                       int send)
 449 {
 450         if (send) {
 451                 pdu->transfer_flags = cpu_to_be32(pdu->transfer_flags);
 452
 453                 cpu_to_be32s(&pdu->transfer_buffer_length);
 454                 cpu_to_be32s(&pdu->start_frame);
 455                 cpu_to_be32s(&pdu->number_of_packets);
 456                 cpu_to_be32s(&pdu->interval);
 457         } else {
 458                 pdu->transfer_flags = be32_to_cpu(pdu->transfer_flags);
 459
 460                 be32_to_cpus(&pdu->transfer_buffer_length);
 461                 be32_to_cpus(&pdu->start_frame);
 462                 be32_to_cpus(&pdu->number_of_packets);
 463                 be32_to_cpus(&pdu->interval);
 464         }
 465 }
 466
 467 static void correct_endian_ret_submit(struct usbip_header_ret_submit *pdu,
 468                                       int send)
 469 {
 470         if (send) {
 471                 cpu_to_be32s(&pdu->status);
 472                 cpu_to_be32s(&pdu->actual_length);
 473                 cpu_to_be32s(&pdu->start_frame);
 474                 cpu_to_be32s(&pdu->number_of_packets);
 475                 cpu_to_be32s(&pdu->error_count);
 476         } else {
 477                 be32_to_cpus(&pdu->status);
 478                 be32_to_cpus(&pdu->actual_length);
 479                 be32_to_cpus(&pdu->start_frame);
 480                 be32_to_cpus(&pdu->number_of_packets);
 481                 be32_to_cpus(&pdu->error_count);
 482         }
 483 }
 484
 485 static void correct_endian_cmd_unlink(struct usbip_header_cmd_unlink *pdu,
 486                                       int send)
 487 {
 488         if (send)
 489                 pdu->seqnum = cpu_to_be32(pdu->seqnum);
 490         else
 491                 pdu->seqnum = be32_to_cpu(pdu->seqnum);
 492 }
 493
 494 static void correct_endian_ret_unlink(struct usbip_header_ret_unlink *pdu,
 495                                       int send)
 496 {
 497         if (send)
 498                 cpu_to_be32s(&pdu->status);
 499         else
 500                 be32_to_cpus(&pdu->status);
 501 }
 502
 503 void usbip_header_correct_endian(struct usbip_header *pdu, int send)
 504 {
 505         __u32 cmd = 0;
 506
 507         if (send)
 508                 cmd = pdu->base.command;
 509
 510         correct_endian_basic(&pdu->base, send);
 511
 512         if (!send)
 513                 cmd = pdu->base.command;
 514
 515         switch (cmd) {
 516         case USBIP_CMD_SUBMIT:
 517                 correct_endian_cmd_submit(&pdu->u.cmd_submit, send);
 518                 break;
 519         case USBIP_RET_SUBMIT:
 520                 correct_endian_ret_submit(&pdu->u.ret_submit, send);
 521                 break;
 522         case USBIP_CMD_UNLINK:
 523                 correct_endian_cmd_unlink(&pdu->u.cmd_unlink, send);
 524                 break;
 525         case USBIP_RET_UNLINK:
 526                 correct_endian_ret_unlink(&pdu->u.ret_unlink, send);
 527                 break;
 528         default:
 529                 /* NOT REACHED */
 530                 pr_err("unknown command\n");
 531                 break;
 532         }
 533 }
 534 EXPORT_SYMBOL_GPL(usbip_header_correct_endian);
 535
 536 static void usbip_iso_packet_correct_endian(
 537                 struct usbip_iso_packet_descriptor *iso, int send)
 538 {
 539         /* does not need all members. but copy all simply. */
 540         if (send) {
 541                 iso->offset     = cpu_to_be32(iso->offset);
 542                 iso->length     = cpu_to_be32(iso->length);
 543                 iso->status     = cpu_to_be32(iso->status);
 544                 iso->actual_length = cpu_to_be32(iso->actual_length);
 545         } else {
 546                 iso->offset     = be32_to_cpu(iso->offset);
 547                 iso->length     = be32_to_cpu(iso->length);
 548                 iso->status     = be32_to_cpu(iso->status);
 549                 iso->actual_length = be32_to_cpu(iso->actual_length);
 550         }
 551 }
 552
 553 static void usbip_pack_iso(struct usbip_iso_packet_descriptor *iso,
 554                            struct usb_iso_packet_descriptor *uiso, int pack)
 555 {
 556         if (pack) {
 557                 iso->offset             = uiso->offset;
 558                 iso->length             = uiso->length;
 559                 iso->status             = uiso->status;
 560                 iso->actual_length      = uiso->actual_length;
 561         } else {
 562                 uiso->offset            = iso->offset;
 563                 uiso->length            = iso->length;
 564                 uiso->status            = iso->status;
 565                 uiso->actual_length     = iso->actual_length;
 566         }
 567 }
 568
 569 /* must free buffer */
 570 struct usbip_iso_packet_descriptor*
 571 usbip_alloc_iso_desc_pdu(struct urb *urb, ssize_t *bufflen)
 572 {
 573         struct usbip_iso_packet_descriptor *iso;
 574         int np = urb->number_of_packets;
 575         ssize_t size = np * sizeof(*iso);
 576         int i;
 577
 578         iso = kzalloc(size, GFP_KERNEL);
 579         if (!iso)
 580                 return NULL;
 581
 582         for (i = 0; i < np; i++) {
 583                 usbip_pack_iso(&iso[i], &urb->iso_frame_desc[i], 1);
 584                 usbip_iso_packet_correct_endian(&iso[i], 1);
 585         }
 586
 587         *bufflen = size;
 588
 589         return iso;
 590 }
 591 EXPORT_SYMBOL_GPL(usbip_alloc_iso_desc_pdu);
 592
 593 /* some members of urb must be substituted before. */
 594 int usbip_recv_iso(struct usbip_device *ud, struct urb *urb)
 595 {
 596         void *buff;
 597         struct usbip_iso_packet_descriptor *iso;
 598         int np = urb->number_of_packets;
 599         int size = np * sizeof(*iso);
 600         int i;
 601         int ret;
 602         int total_length = 0;
 603
 604         if (!usb_pipeisoc(urb->pipe))
 605                 return 0;
 606
 607         /* my Bluetooth dongle gets ISO URBs which are np = 0 */
 608         if (np == 0)
 609                 return 0;
 610
 611         buff = kzalloc(size, GFP_KERNEL);
 612         if (!buff)
 613                 return -ENOMEM;
 614
 615         ret = usbip_recv(ud->tcp_socket, buff, size);
 616         if (ret != size) {
 617                 dev_err(&urb->dev->dev, "recv iso_frame_descriptor, %d\n",
 618                         ret);
 619                 kfree(buff);
 620
 621                 if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
 622                         usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
 623                 else
 624                         usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 625
 626                 return -EPIPE;
 627         }
 628
 629         iso = (struct usbip_iso_packet_descriptor *) buff;
 630         for (i = 0; i < np; i++) {
 631                 usbip_iso_packet_correct_endian(&iso[i], 0);
 632                 usbip_pack_iso(&iso[i], &urb->iso_frame_desc[i], 0);
 633                 total_length += urb->iso_frame_desc[i].actual_length;
 634         }
 635
 636         kfree(buff);
 637
 638         if (total_length != urb->actual_length) {
 639                 dev_err(&urb->dev->dev,
 640                         "total length of iso packets %d not equal to actual length of buffer %d\n",
 641                         total_length, urb->actual_length);
 642
 643                 if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
 644                         usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
 645                 else
 646                         usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 647
 648                 return -EPIPE;
 649         }
 650
 651         return ret;
 652 }
 653 EXPORT_SYMBOL_GPL(usbip_recv_iso);
 654
 655 /*
 656  * This functions restores the padding which was removed for optimizing
 657  * the bandwidth during transfer over tcp/ip
 658  *
 659  * buffer and iso packets need to be stored and be in propeper endian in urb
 660  * before calling this function
 661  */
 662 void usbip_pad_iso(struct usbip_device *ud, struct urb *urb)
 663 {
 664         int np = urb->number_of_packets;
 665         int i;
 666         int actualoffset = urb->actual_length;
 667
 668         if (!usb_pipeisoc(urb->pipe))
 669                 return;
 670
 671         /* if no packets or length of data is 0, then nothing to unpack */
 672         if (np == 0 || urb->actual_length == 0)
 673                 return;
 674
 675         /*
 676          * if actual_length is transfer_buffer_length then no padding is
 677          * present.
 678          */
 679         if (urb->actual_length == urb->transfer_buffer_length)
 680                 return;
 681
 682         /*
 683          * loop over all packets from last to first (to prevent overwriting
 684          * memory when padding) and move them into the proper place
 685          */
 686         for (i = np-1; i > 0; i--) {
 687                 actualoffset -= urb->iso_frame_desc[i].actual_length;
 688                 memmove(urb->transfer_buffer + urb->iso_frame_desc[i].offset,
 689                         urb->transfer_buffer + actualoffset,
 690                         urb->iso_frame_desc[i].actual_length);
 691         }
 692 }
 693 EXPORT_SYMBOL_GPL(usbip_pad_iso);
 694
 695 /* some members of urb must be substituted before. */
 696 int usbip_recv_xbuff(struct usbip_device *ud, struct urb *urb)
 697 {
 698         struct scatterlist *sg;
 699         int ret = 0;
 700         int recv;
 701         int size;
 702         int copy;
 703         int i;
 704
 705         if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC) {
 706                 /* the direction of urb must be OUT. */
 707                 if (usb_pipein(urb->pipe))
 708                         return 0;
 709
 710                 size = urb->transfer_buffer_length;
 711         } else {
 712                 /* the direction of urb must be IN. */
 713                 if (usb_pipeout(urb->pipe))
 714                         return 0;
 715
 716                 size = urb->actual_length;
 717         }
 718
 719         /* no need to recv xbuff */
 720         if (!(size > 0))
 721                 return 0;
 722
 723         if (size > urb->transfer_buffer_length)
 724                 /* should not happen, probably malicious packet */
 725                 goto error;
 726
 727         if (urb->num_sgs) {
 728                 copy = size;
 729                 for_each_sg(urb->sg, sg, urb->num_sgs, i) {
 730                         int recv_size;
 731
 732                         if (copy < sg->length)
 733                                 recv_size = copy;
 734                         else
 735                                 recv_size = sg->length;
 736
 737                         recv = usbip_recv(ud->tcp_socket, sg_virt(sg),
 738                                                 recv_size);
 739
 740                         if (recv != recv_size)
 741                                 goto error;
 742
 743                         copy -= recv;
 744                         ret += recv;
 745
 746                         if (!copy)
 747                                 break;
 748                 }
 749
 750                 if (ret != size)
 751                         goto error;
 752         } else {
 753                 ret = usbip_recv(ud->tcp_socket, urb->transfer_buffer, size);
 754                 if (ret != size)
 755                         goto error;
 756         }
 757
 758         return ret;
 759
 760 error:
 761         dev_err(&urb->dev->dev, "recv xbuf, %d\n", ret);
 762         if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
 763                 usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
 764         else
 765                 usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 766
 767         return -EPIPE;
 768 }
 769 EXPORT_SYMBOL_GPL(usbip_recv_xbuff);
 770
 771 static int __init usbip_core_init(void)
 772 {
 773         int ret;
 774
 775         ret = usbip_init_eh();
 776         if (ret)
 777                 return ret;
 778
 779         return 0;
 780 }
 781
 782 static void __exit usbip_core_exit(void)
 783 {
 784         usbip_finish_eh();
 785         return;
 786 }
 787
 788 module_init(usbip_core_init);
 789 module_exit(usbip_core_exit);
 790
 791 MODULE_AUTHOR(DRIVER_AUTHOR);
 792 MODULE_DESCRIPTION(DRIVER_DESC);
 793 MODULE_LICENSE("GPL");