drivers/usb/usbip/usbip_common.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2003-2008 Takahiro Hirofuchi
   4  * Copyright (C) 2015-2016 Samsung Electronics
   5  *               Krzysztof Opasiak <k.opasiak@samsung.com>
   6  */
   7
   8 #include <asm/byteorder.h>
   9 #include <linux/file.h>
  10 #include <linux/fs.h>
  11 #include <linux/kernel.h>
  12 #include <linux/slab.h>
  13 #include <linux/stat.h>
  14 #include <linux/module.h>
  15 #include <linux/moduleparam.h>
  16 #include <net/sock.h>
  17
  18 #include "usbip_common.h"
  19
  20 #define DRIVER_AUTHOR "Takahiro Hirofuchi <hirofuchi@users.sourceforge.net>"
  21 #define DRIVER_DESC "USB/IP Core"
  22
  23 #ifdef CONFIG_USBIP_DEBUG
  24 unsigned long usbip_debug_flag = 0xffffffff;
  25 #else
  26 unsigned long usbip_debug_flag;
  27 #endif
  28 EXPORT_SYMBOL_GPL(usbip_debug_flag);
  29 module_param(usbip_debug_flag, ulong, S_IRUGO|S_IWUSR);
  30 MODULE_PARM_DESC(usbip_debug_flag, "debug flags (defined in usbip_common.h)");
  31
  32 /* FIXME */
  33 struct device_attribute dev_attr_usbip_debug;
  34 EXPORT_SYMBOL_GPL(dev_attr_usbip_debug);
  35
  36 static ssize_t usbip_debug_show(struct device *dev,
  37                                 struct device_attribute *attr, char *buf)
  38 {
  39         return sprintf(buf, "%lx\n", usbip_debug_flag);
  40 }
  41
  42 static ssize_t usbip_debug_store(struct device *dev,
  43                                  struct device_attribute *attr, const char *buf,
  44                                  size_t count)
  45 {
  46         if (sscanf(buf, "%lx", &usbip_debug_flag) != 1)
  47                 return -EINVAL;
  48         return count;
  49 }
  50 DEVICE_ATTR_RW(usbip_debug);
  51
  52 static void usbip_dump_buffer(char *buff, int bufflen)
  53 {
  54         print_hex_dump(KERN_DEBUG, "usbip-core", DUMP_PREFIX_OFFSET, 16, 4,
  55                        buff, bufflen, false);
  56 }
  57
  58 static void usbip_dump_pipe(unsigned int p)
  59 {
  60         unsigned char type = usb_pipetype(p);
  61         unsigned char ep   = usb_pipeendpoint(p);
  62         unsigned char dev  = usb_pipedevice(p);
  63         unsigned char dir  = usb_pipein(p);
  64
  65         pr_debug("dev(%d) ep(%d) [%s] ", dev, ep, dir ? "IN" : "OUT");
  66
  67         switch (type) {
  68         case PIPE_ISOCHRONOUS:
  69                 pr_debug("ISO\n");
  70                 break;
  71         case PIPE_INTERRUPT:
  72                 pr_debug("INT\n");
  73                 break;
  74         case PIPE_CONTROL:
  75                 pr_debug("CTRL\n");
  76                 break;
  77         case PIPE_BULK:
  78                 pr_debug("BULK\n");
  79                 break;
  80         default:
  81                 pr_debug("ERR\n");
  82                 break;
  83         }
  84 }
  85
  86 static void usbip_dump_usb_device(struct usb_device *udev)
  87 {
  88         struct device *dev = &udev->dev;
  89         int i;
  90
  91         dev_dbg(dev, "       devnum(%d) devpath(%s) usb speed(%s)",
  92                 udev->devnum, udev->devpath, usb_speed_string(udev->speed));
  93
  94         pr_debug("tt hub ttport %d\n", udev->ttport);
  95
  96         dev_dbg(dev, "                    ");
  97         for (i = 0; i < 16; i++)
  98                 pr_debug(" %2u", i);
  99         pr_debug("\n");
 100
 101         dev_dbg(dev, "       toggle0(IN) :");
 102         for (i = 0; i < 16; i++)
 103                 pr_debug(" %2u", (udev->toggle[0] & (1 << i)) ? 1 : 0);
 104         pr_debug("\n");
 105
 106         dev_dbg(dev, "       toggle1(OUT):");
 107         for (i = 0; i < 16; i++)
 108                 pr_debug(" %2u", (udev->toggle[1] & (1 << i)) ? 1 : 0);
 109         pr_debug("\n");
 110
 111         dev_dbg(dev, "       epmaxp_in   :");
 112         for (i = 0; i < 16; i++) {
 113                 if (udev->ep_in[i])
 114                         pr_debug(" %2u",
 115                             le16_to_cpu(udev->ep_in[i]->desc.wMaxPacketSize));
 116         }
 117         pr_debug("\n");
 118
 119         dev_dbg(dev, "       epmaxp_out  :");
 120         for (i = 0; i < 16; i++) {
 121                 if (udev->ep_out[i])
 122                         pr_debug(" %2u",
 123                             le16_to_cpu(udev->ep_out[i]->desc.wMaxPacketSize));
 124         }
 125         pr_debug("\n");
 126
 127         dev_dbg(dev, "parent %s, bus %s\n", dev_name(&udev->parent->dev),
 128                 udev->bus->bus_name);
 129
 130         dev_dbg(dev, "have_langid %d, string_langid %d\n",
 131                 udev->have_langid, udev->string_langid);
 132
 133         dev_dbg(dev, "maxchild %d\n", udev->maxchild);
 134 }
 135
 136 static void usbip_dump_request_type(__u8 rt)
 137 {
 138         switch (rt & USB_RECIP_MASK) {
 139         case USB_RECIP_DEVICE:
 140                 pr_debug("DEVICE");
 141                 break;
 142         case USB_RECIP_INTERFACE:
 143                 pr_debug("INTERF");
 144                 break;
 145         case USB_RECIP_ENDPOINT:
 146                 pr_debug("ENDPOI");
 147                 break;
 148         case USB_RECIP_OTHER:
 149                 pr_debug("OTHER ");
 150                 break;
 151         default:
 152                 pr_debug("------");
 153                 break;
 154         }
 155 }
 156
 157 static void usbip_dump_usb_ctrlrequest(struct usb_ctrlrequest *cmd)
 158 {
 159         if (!cmd) {
 160                 pr_debug("       : null pointer\n");
 161                 return;
 162         }
 163
 164         pr_debug("       ");
 165         pr_debug("bRequestType(%02X) bRequest(%02X) wValue(%04X) wIndex(%04X) wLength(%04X) ",
 166                  cmd->bRequestType, cmd->bRequest,
 167                  cmd->wValue, cmd->wIndex, cmd->wLength);
 168         pr_debug("\n       ");
 169
 170         if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD) {
 171                 pr_debug("STANDARD ");
 172                 switch (cmd->bRequest) {
 173                 case USB_REQ_GET_STATUS:
 174                         pr_debug("GET_STATUS\n");
 175                         break;
 176                 case USB_REQ_CLEAR_FEATURE:
 177                         pr_debug("CLEAR_FEAT\n");
 178                         break;
 179                 case USB_REQ_SET_FEATURE:
 180                         pr_debug("SET_FEAT\n");
 181                         break;
 182                 case USB_REQ_SET_ADDRESS:
 183                         pr_debug("SET_ADDRRS\n");
 184                         break;
 185                 case USB_REQ_GET_DESCRIPTOR:
 186                         pr_debug("GET_DESCRI\n");
 187                         break;
 188                 case USB_REQ_SET_DESCRIPTOR:
 189                         pr_debug("SET_DESCRI\n");
 190                         break;
 191                 case USB_REQ_GET_CONFIGURATION:
 192                         pr_debug("GET_CONFIG\n");
 193                         break;
 194                 case USB_REQ_SET_CONFIGURATION:
 195                         pr_debug("SET_CONFIG\n");
 196                         break;
 197                 case USB_REQ_GET_INTERFACE:
 198                         pr_debug("GET_INTERF\n");
 199                         break;
 200                 case USB_REQ_SET_INTERFACE:
 201                         pr_debug("SET_INTERF\n");
 202                         break;
 203                 case USB_REQ_SYNCH_FRAME:
 204                         pr_debug("SYNC_FRAME\n");
 205                         break;
 206                 default:
 207                         pr_debug("REQ(%02X)\n", cmd->bRequest);
 208                         break;
 209                 }
 210                 usbip_dump_request_type(cmd->bRequestType);
 211         } else if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_CLASS) {
 212                 pr_debug("CLASS\n");
 213         } else if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_VENDOR) {
 214                 pr_debug("VENDOR\n");
 215         } else if ((cmd->bRequestType & USB_TYPE_MASK) == USB_TYPE_RESERVED) {
 216                 pr_debug("RESERVED\n");
 217         }
 218 }
 219
 220 void usbip_dump_urb(struct urb *urb)
 221 {
 222         struct device *dev;
 223
 224         if (!urb) {
 225                 pr_debug("urb: null pointer!!\n");
 226                 return;
 227         }
 228
 229         if (!urb->dev) {
 230                 pr_debug("urb->dev: null pointer!!\n");
 231                 return;
 232         }
 233
 234         dev = &urb->dev->dev;
 235
 236         usbip_dump_usb_device(urb->dev);
 237
 238         dev_dbg(dev, "   pipe                  :%08x ", urb->pipe);
 239
 240         usbip_dump_pipe(urb->pipe);
 241
 242         dev_dbg(dev, "   status                :%d\n", urb->status);
 243         dev_dbg(dev, "   transfer_flags        :%08X\n", urb->transfer_flags);
 244         dev_dbg(dev, "   transfer_buffer_length:%d\n",
 245                                                 urb->transfer_buffer_length);
 246         dev_dbg(dev, "   actual_length         :%d\n", urb->actual_length);
 247
 248         if (urb->setup_packet && usb_pipetype(urb->pipe) == PIPE_CONTROL)
 249                 usbip_dump_usb_ctrlrequest(
 250                         (struct usb_ctrlrequest *)urb->setup_packet);
 251
 252         dev_dbg(dev, "   start_frame           :%d\n", urb->start_frame);
 253         dev_dbg(dev, "   number_of_packets     :%d\n", urb->number_of_packets);
 254         dev_dbg(dev, "   interval              :%d\n", urb->interval);
 255         dev_dbg(dev, "   error_count           :%d\n", urb->error_count);
 256 }
 257 EXPORT_SYMBOL_GPL(usbip_dump_urb);
 258
 259 void usbip_dump_header(struct usbip_header *pdu)
 260 {
 261         pr_debug("BASE: cmd %u seq %u devid %u dir %u ep %u\n",
 262                  pdu->base.command,
 263                  pdu->base.seqnum,
 264                  pdu->base.devid,
 265                  pdu->base.direction,
 266                  pdu->base.ep);
 267
 268         switch (pdu->base.command) {
 269         case USBIP_CMD_SUBMIT:
 270                 pr_debug("USBIP_CMD_SUBMIT: x_flags %u x_len %u sf %u #p %d iv %d\n",
 271                          pdu->u.cmd_submit.transfer_flags,
 272                          pdu->u.cmd_submit.transfer_buffer_length,
 273                          pdu->u.cmd_submit.start_frame,
 274                          pdu->u.cmd_submit.number_of_packets,
 275                          pdu->u.cmd_submit.interval);
 276                 break;
 277         case USBIP_CMD_UNLINK:
 278                 pr_debug("USBIP_CMD_UNLINK: seq %u\n",
 279                          pdu->u.cmd_unlink.seqnum);
 280                 break;
 281         case USBIP_RET_SUBMIT:
 282                 pr_debug("USBIP_RET_SUBMIT: st %d al %u sf %d #p %d ec %d\n",
 283                          pdu->u.ret_submit.status,
 284                          pdu->u.ret_submit.actual_length,
 285                          pdu->u.ret_submit.start_frame,
 286                          pdu->u.ret_submit.number_of_packets,
 287                          pdu->u.ret_submit.error_count);
 288                 break;
 289         case USBIP_RET_UNLINK:
 290                 pr_debug("USBIP_RET_UNLINK: status %d\n",
 291                          pdu->u.ret_unlink.status);
 292                 break;
 293         default:
 294                 /* NOT REACHED */
 295                 pr_err("unknown command\n");
 296                 break;
 297         }
 298 }
 299 EXPORT_SYMBOL_GPL(usbip_dump_header);
 300
 301 /* Receive data over TCP/IP. */
 302 int usbip_recv(struct socket *sock, void *buf, int size)
 303 {
 304         int result;
 305         struct kvec iov = {.iov_base = buf, .iov_len = size};
 306         struct msghdr msg = {.msg_flags = MSG_NOSIGNAL};
 307         int total = 0;
 308
 309         if (!sock || !buf || !size)
 310                 return -EINVAL;
 311
 312         iov_iter_kvec(&msg.msg_iter, ITER_DEST, &iov, 1, size);
 313
 314         usbip_dbg_xmit("enter\n");
 315
 316         do {
 317                 sock->sk->sk_allocation = GFP_NOIO;
 318                 sock->sk->sk_use_task_frag = false;
 319
 320                 result = sock_recvmsg(sock, &msg, MSG_WAITALL);
 321                 if (result <= 0)
 322                         goto err;
 323
 324                 total += result;
 325         } while (msg_data_left(&msg));
 326
 327         if (usbip_dbg_flag_xmit) {
 328                 pr_debug("receiving....\n");
 329                 usbip_dump_buffer(buf, size);
 330                 pr_debug("received, osize %d ret %d size %zd total %d\n",
 331                          size, result, msg_data_left(&msg), total);
 332         }
 333
 334         return total;
 335
 336 err:
 337         return result;
 338 }
 339 EXPORT_SYMBOL_GPL(usbip_recv);
 340
 341 /* there may be more cases to tweak the flags. */
 342 static unsigned int tweak_transfer_flags(unsigned int flags)
 343 {
 344         flags &= ~URB_NO_TRANSFER_DMA_MAP;
 345         return flags;
 346 }
 347
 348 /*
 349  * USBIP driver packs URB transfer flags in PDUs that are exchanged
 350  * between Server (usbip_host) and Client (vhci_hcd). URB_* flags
 351  * are internal to kernel and could change. Where as USBIP URB flags
 352  * exchanged in PDUs are USBIP user API must not change.
 353  *
 354  * USBIP_URB* flags are exported as explicit API and client and server
 355  * do mapping from kernel flags to USBIP_URB*. Details as follows:
 356  *
 357  * Client tx path (USBIP_CMD_SUBMIT):
 358  * - Maps URB_* to USBIP_URB_* when it sends USBIP_CMD_SUBMIT packet.
 359  *
 360  * Server rx path (USBIP_CMD_SUBMIT):
 361  * - Maps USBIP_URB_* to URB_* when it receives USBIP_CMD_SUBMIT packet.
 362  *
 363  * Flags aren't included in USBIP_CMD_UNLINK and USBIP_RET_SUBMIT packets
 364  * and no special handling is needed for them in the following cases:
 365  * - Server rx path (USBIP_CMD_UNLINK)
 366  * - Client rx path & Server tx path (USBIP_RET_SUBMIT)
 367  *
 368  * Code paths:
 369  * usbip_pack_pdu() is the common routine that handles packing pdu from
 370  * urb and unpack pdu to an urb.
 371  *
 372  * usbip_pack_cmd_submit() and usbip_pack_ret_submit() handle
 373  * USBIP_CMD_SUBMIT and USBIP_RET_SUBMIT respectively.
 374  *
 375  * usbip_map_urb_to_usbip() and usbip_map_usbip_to_urb() are used
 376  * by usbip_pack_cmd_submit() and usbip_pack_ret_submit() to map
 377  * flags.
 378  */
 379
 380 struct urb_to_usbip_flags {
 381         u32 urb_flag;
 382         u32 usbip_flag;
 383 };
 384
 385 #define NUM_USBIP_FLAGS 17
 386
 387 static const struct urb_to_usbip_flags flag_map[NUM_USBIP_FLAGS] = {
 388         {URB_SHORT_NOT_OK, USBIP_URB_SHORT_NOT_OK},
 389         {URB_ISO_ASAP, USBIP_URB_ISO_ASAP},
 390         {URB_NO_TRANSFER_DMA_MAP, USBIP_URB_NO_TRANSFER_DMA_MAP},
 391         {URB_ZERO_PACKET, USBIP_URB_ZERO_PACKET},
 392         {URB_NO_INTERRUPT, USBIP_URB_NO_INTERRUPT},
 393         {URB_FREE_BUFFER, USBIP_URB_FREE_BUFFER},
 394         {URB_DIR_IN, USBIP_URB_DIR_IN},
 395         {URB_DIR_OUT, USBIP_URB_DIR_OUT},
 396         {URB_DIR_MASK, USBIP_URB_DIR_MASK},
 397         {URB_DMA_MAP_SINGLE, USBIP_URB_DMA_MAP_SINGLE},
 398         {URB_DMA_MAP_PAGE, USBIP_URB_DMA_MAP_PAGE},
 399         {URB_DMA_MAP_SG, USBIP_URB_DMA_MAP_SG},
 400         {URB_MAP_LOCAL, USBIP_URB_MAP_LOCAL},
 401         {URB_SETUP_MAP_SINGLE, USBIP_URB_SETUP_MAP_SINGLE},
 402         {URB_SETUP_MAP_LOCAL, USBIP_URB_SETUP_MAP_LOCAL},
 403         {URB_DMA_SG_COMBINED, USBIP_URB_DMA_SG_COMBINED},
 404         {URB_ALIGNED_TEMP_BUFFER, USBIP_URB_ALIGNED_TEMP_BUFFER},
 405 };
 406
 407 static unsigned int urb_to_usbip(unsigned int flags)
 408 {
 409         unsigned int map_flags = 0;
 410         int loop;
 411
 412         for (loop = 0; loop < NUM_USBIP_FLAGS; loop++) {
 413                 if (flags & flag_map[loop].urb_flag)
 414                         map_flags |= flag_map[loop].usbip_flag;
 415         }
 416
 417         return map_flags;
 418 }
 419
 420 static unsigned int usbip_to_urb(unsigned int flags)
 421 {
 422         unsigned int map_flags = 0;
 423         int loop;
 424
 425         for (loop = 0; loop < NUM_USBIP_FLAGS; loop++) {
 426                 if (flags & flag_map[loop].usbip_flag)
 427                         map_flags |= flag_map[loop].urb_flag;
 428         }
 429
 430         return map_flags;
 431 }
 432
 433 static void usbip_pack_cmd_submit(struct usbip_header *pdu, struct urb *urb,
 434                                   int pack)
 435 {
 436         struct usbip_header_cmd_submit *spdu = &pdu->u.cmd_submit;
 437
 438         /*
 439          * Some members are not still implemented in usbip. I hope this issue
 440          * will be discussed when usbip is ported to other operating systems.
 441          */
 442         if (pack) {
 443                 /* map after tweaking the urb flags */
 444                 spdu->transfer_flags = urb_to_usbip(tweak_transfer_flags(urb->transfer_flags));
 445                 spdu->transfer_buffer_length    = urb->transfer_buffer_length;
 446                 spdu->start_frame               = urb->start_frame;
 447                 spdu->number_of_packets         = urb->number_of_packets;
 448                 spdu->interval                  = urb->interval;
 449         } else  {
 450                 urb->transfer_flags         = usbip_to_urb(spdu->transfer_flags);
 451                 urb->transfer_buffer_length = spdu->transfer_buffer_length;
 452                 urb->start_frame            = spdu->start_frame;
 453                 urb->number_of_packets      = spdu->number_of_packets;
 454                 urb->interval               = spdu->interval;
 455         }
 456 }
 457
 458 static void usbip_pack_ret_submit(struct usbip_header *pdu, struct urb *urb,
 459                                   int pack)
 460 {
 461         struct usbip_header_ret_submit *rpdu = &pdu->u.ret_submit;
 462
 463         if (pack) {
 464                 rpdu->status            = urb->status;
 465                 rpdu->actual_length     = urb->actual_length;
 466                 rpdu->start_frame       = urb->start_frame;
 467                 rpdu->number_of_packets = urb->number_of_packets;
 468                 rpdu->error_count       = urb->error_count;
 469         } else {
 470                 urb->status             = rpdu->status;
 471                 urb->actual_length      = rpdu->actual_length;
 472                 urb->start_frame        = rpdu->start_frame;
 473                 urb->number_of_packets = rpdu->number_of_packets;
 474                 urb->error_count        = rpdu->error_count;
 475         }
 476 }
 477
 478 void usbip_pack_pdu(struct usbip_header *pdu, struct urb *urb, int cmd,
 479                     int pack)
 480 {
 481         switch (cmd) {
 482         case USBIP_CMD_SUBMIT:
 483                 usbip_pack_cmd_submit(pdu, urb, pack);
 484                 break;
 485         case USBIP_RET_SUBMIT:
 486                 usbip_pack_ret_submit(pdu, urb, pack);
 487                 break;
 488         default:
 489                 /* NOT REACHED */
 490                 pr_err("unknown command\n");
 491                 break;
 492         }
 493 }
 494 EXPORT_SYMBOL_GPL(usbip_pack_pdu);
 495
 496 static void correct_endian_basic(struct usbip_header_basic *base, int send)
 497 {
 498         if (send) {
 499                 base->command   = cpu_to_be32(base->command);
 500                 base->seqnum    = cpu_to_be32(base->seqnum);
 501                 base->devid     = cpu_to_be32(base->devid);
 502                 base->direction = cpu_to_be32(base->direction);
 503                 base->ep        = cpu_to_be32(base->ep);
 504         } else {
 505                 base->command   = be32_to_cpu(base->command);
 506                 base->seqnum    = be32_to_cpu(base->seqnum);
 507                 base->devid     = be32_to_cpu(base->devid);
 508                 base->direction = be32_to_cpu(base->direction);
 509                 base->ep        = be32_to_cpu(base->ep);
 510         }
 511 }
 512
 513 static void correct_endian_cmd_submit(struct usbip_header_cmd_submit *pdu,
 514                                       int send)
 515 {
 516         if (send) {
 517                 pdu->transfer_flags = cpu_to_be32(pdu->transfer_flags);
 518
 519                 cpu_to_be32s(&pdu->transfer_buffer_length);
 520                 cpu_to_be32s(&pdu->start_frame);
 521                 cpu_to_be32s(&pdu->number_of_packets);
 522                 cpu_to_be32s(&pdu->interval);
 523         } else {
 524                 pdu->transfer_flags = be32_to_cpu(pdu->transfer_flags);
 525
 526                 be32_to_cpus(&pdu->transfer_buffer_length);
 527                 be32_to_cpus(&pdu->start_frame);
 528                 be32_to_cpus(&pdu->number_of_packets);
 529                 be32_to_cpus(&pdu->interval);
 530         }
 531 }
 532
 533 static void correct_endian_ret_submit(struct usbip_header_ret_submit *pdu,
 534                                       int send)
 535 {
 536         if (send) {
 537                 cpu_to_be32s(&pdu->status);
 538                 cpu_to_be32s(&pdu->actual_length);
 539                 cpu_to_be32s(&pdu->start_frame);
 540                 cpu_to_be32s(&pdu->number_of_packets);
 541                 cpu_to_be32s(&pdu->error_count);
 542         } else {
 543                 be32_to_cpus(&pdu->status);
 544                 be32_to_cpus(&pdu->actual_length);
 545                 be32_to_cpus(&pdu->start_frame);
 546                 be32_to_cpus(&pdu->number_of_packets);
 547                 be32_to_cpus(&pdu->error_count);
 548         }
 549 }
 550
 551 static void correct_endian_cmd_unlink(struct usbip_header_cmd_unlink *pdu,
 552                                       int send)
 553 {
 554         if (send)
 555                 pdu->seqnum = cpu_to_be32(pdu->seqnum);
 556         else
 557                 pdu->seqnum = be32_to_cpu(pdu->seqnum);
 558 }
 559
 560 static void correct_endian_ret_unlink(struct usbip_header_ret_unlink *pdu,
 561                                       int send)
 562 {
 563         if (send)
 564                 cpu_to_be32s(&pdu->status);
 565         else
 566                 be32_to_cpus(&pdu->status);
 567 }
 568
 569 void usbip_header_correct_endian(struct usbip_header *pdu, int send)
 570 {
 571         __u32 cmd = 0;
 572
 573         if (send)
 574                 cmd = pdu->base.command;
 575
 576         correct_endian_basic(&pdu->base, send);
 577
 578         if (!send)
 579                 cmd = pdu->base.command;
 580
 581         switch (cmd) {
 582         case USBIP_CMD_SUBMIT:
 583                 correct_endian_cmd_submit(&pdu->u.cmd_submit, send);
 584                 break;
 585         case USBIP_RET_SUBMIT:
 586                 correct_endian_ret_submit(&pdu->u.ret_submit, send);
 587                 break;
 588         case USBIP_CMD_UNLINK:
 589                 correct_endian_cmd_unlink(&pdu->u.cmd_unlink, send);
 590                 break;
 591         case USBIP_RET_UNLINK:
 592                 correct_endian_ret_unlink(&pdu->u.ret_unlink, send);
 593                 break;
 594         default:
 595                 /* NOT REACHED */
 596                 pr_err("unknown command\n");
 597                 break;
 598         }
 599 }
 600 EXPORT_SYMBOL_GPL(usbip_header_correct_endian);
 601
 602 static void usbip_iso_packet_correct_endian(
 603                 struct usbip_iso_packet_descriptor *iso, int send)
 604 {
 605         /* does not need all members. but copy all simply. */
 606         if (send) {
 607                 iso->offset     = cpu_to_be32(iso->offset);
 608                 iso->length     = cpu_to_be32(iso->length);
 609                 iso->status     = cpu_to_be32(iso->status);
 610                 iso->actual_length = cpu_to_be32(iso->actual_length);
 611         } else {
 612                 iso->offset     = be32_to_cpu(iso->offset);
 613                 iso->length     = be32_to_cpu(iso->length);
 614                 iso->status     = be32_to_cpu(iso->status);
 615                 iso->actual_length = be32_to_cpu(iso->actual_length);
 616         }
 617 }
 618
 619 static void usbip_pack_iso(struct usbip_iso_packet_descriptor *iso,
 620                            struct usb_iso_packet_descriptor *uiso, int pack)
 621 {
 622         if (pack) {
 623                 iso->offset             = uiso->offset;
 624                 iso->length             = uiso->length;
 625                 iso->status             = uiso->status;
 626                 iso->actual_length      = uiso->actual_length;
 627         } else {
 628                 uiso->offset            = iso->offset;
 629                 uiso->length            = iso->length;
 630                 uiso->status            = iso->status;
 631                 uiso->actual_length     = iso->actual_length;
 632         }
 633 }
 634
 635 /* must free buffer */
 636 struct usbip_iso_packet_descriptor*
 637 usbip_alloc_iso_desc_pdu(struct urb *urb, ssize_t *bufflen)
 638 {
 639         struct usbip_iso_packet_descriptor *iso;
 640         int np = urb->number_of_packets;
 641         ssize_t size = np * sizeof(*iso);
 642         int i;
 643
 644         iso = kzalloc(size, GFP_KERNEL);
 645         if (!iso)
 646                 return NULL;
 647
 648         for (i = 0; i < np; i++) {
 649                 usbip_pack_iso(&iso[i], &urb->iso_frame_desc[i], 1);
 650                 usbip_iso_packet_correct_endian(&iso[i], 1);
 651         }
 652
 653         *bufflen = size;
 654
 655         return iso;
 656 }
 657 EXPORT_SYMBOL_GPL(usbip_alloc_iso_desc_pdu);
 658
 659 /* some members of urb must be substituted before. */
 660 int usbip_recv_iso(struct usbip_device *ud, struct urb *urb)
 661 {
 662         void *buff;
 663         struct usbip_iso_packet_descriptor *iso;
 664         int np = urb->number_of_packets;
 665         int size = np * sizeof(*iso);
 666         int i;
 667         int ret;
 668         int total_length = 0;
 669
 670         if (!usb_pipeisoc(urb->pipe))
 671                 return 0;
 672
 673         /* my Bluetooth dongle gets ISO URBs which are np = 0 */
 674         if (np == 0)
 675                 return 0;
 676
 677         buff = kzalloc(size, GFP_KERNEL);
 678         if (!buff)
 679                 return -ENOMEM;
 680
 681         ret = usbip_recv(ud->tcp_socket, buff, size);
 682         if (ret != size) {
 683                 dev_err(&urb->dev->dev, "recv iso_frame_descriptor, %d\n",
 684                         ret);
 685                 kfree(buff);
 686
 687                 if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
 688                         usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
 689                 else
 690                         usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 691
 692                 return -EPIPE;
 693         }
 694
 695         iso = (struct usbip_iso_packet_descriptor *) buff;
 696         for (i = 0; i < np; i++) {
 697                 usbip_iso_packet_correct_endian(&iso[i], 0);
 698                 usbip_pack_iso(&iso[i], &urb->iso_frame_desc[i], 0);
 699                 total_length += urb->iso_frame_desc[i].actual_length;
 700         }
 701
 702         kfree(buff);
 703
 704         if (total_length != urb->actual_length) {
 705                 dev_err(&urb->dev->dev,
 706                         "total length of iso packets %d not equal to actual length of buffer %d\n",
 707                         total_length, urb->actual_length);
 708
 709                 if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
 710                         usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
 711                 else
 712                         usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 713
 714                 return -EPIPE;
 715         }
 716
 717         return ret;
 718 }
 719 EXPORT_SYMBOL_GPL(usbip_recv_iso);
 720
 721 /*
 722  * This functions restores the padding which was removed for optimizing
 723  * the bandwidth during transfer over tcp/ip
 724  *
 725  * buffer and iso packets need to be stored and be in propeper endian in urb
 726  * before calling this function
 727  */
 728 void usbip_pad_iso(struct usbip_device *ud, struct urb *urb)
 729 {
 730         int np = urb->number_of_packets;
 731         int i;
 732         int actualoffset = urb->actual_length;
 733
 734         if (!usb_pipeisoc(urb->pipe))
 735                 return;
 736
 737         /* if no packets or length of data is 0, then nothing to unpack */
 738         if (np == 0 || urb->actual_length == 0)
 739                 return;
 740
 741         /*
 742          * if actual_length is transfer_buffer_length then no padding is
 743          * present.
 744          */
 745         if (urb->actual_length == urb->transfer_buffer_length)
 746                 return;
 747
 748         /*
 749          * loop over all packets from last to first (to prevent overwriting
 750          * memory when padding) and move them into the proper place
 751          */
 752         for (i = np-1; i > 0; i--) {
 753                 actualoffset -= urb->iso_frame_desc[i].actual_length;
 754                 memmove(urb->transfer_buffer + urb->iso_frame_desc[i].offset,
 755                         urb->transfer_buffer + actualoffset,
 756                         urb->iso_frame_desc[i].actual_length);
 757         }
 758 }
 759 EXPORT_SYMBOL_GPL(usbip_pad_iso);
 760
 761 /* some members of urb must be substituted before. */
 762 int usbip_recv_xbuff(struct usbip_device *ud, struct urb *urb)
 763 {
 764         struct scatterlist *sg;
 765         int ret = 0;
 766         int recv;
 767         int size;
 768         int copy;
 769         int i;
 770
 771         if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC) {
 772                 /* the direction of urb must be OUT. */
 773                 if (usb_pipein(urb->pipe))
 774                         return 0;
 775
 776                 size = urb->transfer_buffer_length;
 777         } else {
 778                 /* the direction of urb must be IN. */
 779                 if (usb_pipeout(urb->pipe))
 780                         return 0;
 781
 782                 size = urb->actual_length;
 783         }
 784
 785         /* no need to recv xbuff */
 786         if (!(size > 0))
 787                 return 0;
 788
 789         if (size > urb->transfer_buffer_length)
 790                 /* should not happen, probably malicious packet */
 791                 goto error;
 792
 793         if (urb->num_sgs) {
 794                 copy = size;
 795                 for_each_sg(urb->sg, sg, urb->num_sgs, i) {
 796                         int recv_size;
 797
 798                         if (copy < sg->length)
 799                                 recv_size = copy;
 800                         else
 801                                 recv_size = sg->length;
 802
 803                         recv = usbip_recv(ud->tcp_socket, sg_virt(sg),
 804                                                 recv_size);
 805
 806                         if (recv != recv_size)
 807                                 goto error;
 808
 809                         copy -= recv;
 810                         ret += recv;
 811
 812                         if (!copy)
 813                                 break;
 814                 }
 815
 816                 if (ret != size)
 817                         goto error;
 818         } else {
 819                 ret = usbip_recv(ud->tcp_socket, urb->transfer_buffer, size);
 820                 if (ret != size)
 821                         goto error;
 822         }
 823
 824         return ret;
 825
 826 error:
 827         dev_err(&urb->dev->dev, "recv xbuf, %d\n", ret);
 828         if (ud->side == USBIP_STUB || ud->side == USBIP_VUDC)
 829                 usbip_event_add(ud, SDEV_EVENT_ERROR_TCP);
 830         else
 831                 usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 832
 833         return -EPIPE;
 834 }
 835 EXPORT_SYMBOL_GPL(usbip_recv_xbuff);
 836
 837 static int __init usbip_core_init(void)
 838 {
 839         return usbip_init_eh();
 840 }
 841
 842 static void __exit usbip_core_exit(void)
 843 {
 844         usbip_finish_eh();
 845         return;
 846 }
 847
 848 module_init(usbip_core_init);
 849 module_exit(usbip_core_exit);
 850
 851 MODULE_AUTHOR(DRIVER_AUTHOR);
 852 MODULE_DESCRIPTION(DRIVER_DESC);
 853 MODULE_LICENSE("GPL");