Pileus Git - ~andy/linux/blob - drivers/staging/usbip/vhci_hcd.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 <linux/init.h>
  21 #include <linux/file.h>
  22 #include <linux/kernel.h>
  23 #include <linux/kthread.h>
  24 #include <linux/module.h>
  25 #include <linux/platform_device.h>
  26 #include <linux/slab.h>
  27
  28 #include "usbip_common.h"
  29 #include "vhci.h"
  30
  31 #define DRIVER_AUTHOR "Takahiro Hirofuchi"
  32 #define DRIVER_DESC "USB/IP 'Virtual' Host Controller (VHCI) Driver"
  33
  34 /*
  35  * TODO
  36  *      - update root hub emulation
  37  *      - move the emulation code to userland ?
  38  *              porting to other operating systems
  39  *              minimize kernel code
  40  *      - add suspend/resume code
  41  *      - clean up everything
  42  */
  43
  44 /* See usb gadget dummy hcd */
  45
  46 static int vhci_hub_status(struct usb_hcd *hcd, char *buff);
  47 static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
  48                             u16 wIndex, char *buff, u16 wLength);
  49 static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
  50                             gfp_t mem_flags);
  51 static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status);
  52 static int vhci_start(struct usb_hcd *vhci_hcd);
  53 static void vhci_stop(struct usb_hcd *hcd);
  54 static int vhci_get_frame_number(struct usb_hcd *hcd);
  55
  56 static const char driver_name[] = "vhci_hcd";
  57 static const char driver_desc[] = "USB/IP Virtual Host Controller";
  58
  59 struct vhci_hcd *the_controller;
  60
  61 static const char * const bit_desc[] = {
  62         "CONNECTION",           /*0*/
  63         "ENABLE",               /*1*/
  64         "SUSPEND",              /*2*/
  65         "OVER_CURRENT",         /*3*/
  66         "RESET",                /*4*/
  67         "R5",                   /*5*/
  68         "R6",                   /*6*/
  69         "R7",                   /*7*/
  70         "POWER",                /*8*/
  71         "LOWSPEED",             /*9*/
  72         "HIGHSPEED",            /*10*/
  73         "PORT_TEST",            /*11*/
  74         "INDICATOR",            /*12*/
  75         "R13",                  /*13*/
  76         "R14",                  /*14*/
  77         "R15",                  /*15*/
  78         "C_CONNECTION",         /*16*/
  79         "C_ENABLE",             /*17*/
  80         "C_SUSPEND",            /*18*/
  81         "C_OVER_CURRENT",       /*19*/
  82         "C_RESET",              /*20*/
  83         "R21",                  /*21*/
  84         "R22",                  /*22*/
  85         "R23",                  /*23*/
  86         "R24",                  /*24*/
  87         "R25",                  /*25*/
  88         "R26",                  /*26*/
  89         "R27",                  /*27*/
  90         "R28",                  /*28*/
  91         "R29",                  /*29*/
  92         "R30",                  /*30*/
  93         "R31",                  /*31*/
  94 };
  95
  96 static void dump_port_status_diff(u32 prev_status, u32 new_status)
  97 {
  98         int i = 0;
  99         u32 bit = 1;
 100
 101         pr_debug("status prev -> new: %08x -> %08x\n", prev_status, new_status);
 102         while (bit) {
 103                 u32 prev = prev_status & bit;
 104                 u32 new = new_status & bit;
 105                 char change;
 106
 107                 if (!prev && new)
 108                         change = '+';
 109                 else if (prev && !new)
 110                         change = '-';
 111                 else
 112                         change = ' ';
 113
 114                 if (prev || new)
 115                         pr_debug(" %c%s\n", change, bit_desc[i]);
 116                 bit <<= 1;
 117                 i++;
 118         }
 119         pr_debug("\n");
 120 }
 121
 122 void rh_port_connect(int rhport, enum usb_device_speed speed)
 123 {
 124         usbip_dbg_vhci_rh("rh_port_connect %d\n", rhport);
 125
 126         spin_lock(&the_controller->lock);
 127
 128         the_controller->port_status[rhport] |= USB_PORT_STAT_CONNECTION
 129                 | (1 << USB_PORT_FEAT_C_CONNECTION);
 130
 131         switch (speed) {
 132         case USB_SPEED_HIGH:
 133                 the_controller->port_status[rhport] |= USB_PORT_STAT_HIGH_SPEED;
 134                 break;
 135         case USB_SPEED_LOW:
 136                 the_controller->port_status[rhport] |= USB_PORT_STAT_LOW_SPEED;
 137                 break;
 138         default:
 139                 break;
 140         }
 141
 142         spin_unlock(&the_controller->lock);
 143
 144         usb_hcd_poll_rh_status(vhci_to_hcd(the_controller));
 145 }
 146
 147 static void rh_port_disconnect(int rhport)
 148 {
 149         usbip_dbg_vhci_rh("rh_port_disconnect %d\n", rhport);
 150
 151         spin_lock(&the_controller->lock);
 152
 153         the_controller->port_status[rhport] &= ~USB_PORT_STAT_CONNECTION;
 154         the_controller->port_status[rhport] |=
 155                                         (1 << USB_PORT_FEAT_C_CONNECTION);
 156
 157         spin_unlock(&the_controller->lock);
 158         usb_hcd_poll_rh_status(vhci_to_hcd(the_controller));
 159 }
 160
 161 #define PORT_C_MASK                             \
 162         ((USB_PORT_STAT_C_CONNECTION            \
 163           | USB_PORT_STAT_C_ENABLE              \
 164           | USB_PORT_STAT_C_SUSPEND             \
 165           | USB_PORT_STAT_C_OVERCURRENT         \
 166           | USB_PORT_STAT_C_RESET) << 16)
 167
 168 /*
 169  * Returns 0 if the status hasn't changed, or the number of bytes in buf.
 170  * Ports are 0-indexed from the HCD point of view,
 171  * and 1-indexed from the USB core pointer of view.
 172  *
 173  * @buf: a bitmap to show which port status has been changed.
 174  *  bit  0: reserved
 175  *  bit  1: the status of port 0 has been changed.
 176  *  bit  2: the status of port 1 has been changed.
 177  *  ...
 178  */
 179 static int vhci_hub_status(struct usb_hcd *hcd, char *buf)
 180 {
 181         struct vhci_hcd *vhci;
 182         int             retval;
 183         int             rhport;
 184         int             changed = 0;
 185
 186         retval = DIV_ROUND_UP(VHCI_NPORTS + 1, 8);
 187         memset(buf, 0, retval);
 188
 189         vhci = hcd_to_vhci(hcd);
 190
 191         spin_lock(&vhci->lock);
 192         if (!HCD_HW_ACCESSIBLE(hcd)) {
 193                 usbip_dbg_vhci_rh("hw accessible flag not on?\n");
 194                 goto done;
 195         }
 196
 197         /* check pseudo status register for each port */
 198         for (rhport = 0; rhport < VHCI_NPORTS; rhport++) {
 199                 if ((vhci->port_status[rhport] & PORT_C_MASK)) {
 200                         /* The status of a port has been changed, */
 201                         usbip_dbg_vhci_rh("port %d status changed\n", rhport);
 202
 203                         buf[(rhport + 1) / 8] |= 1 << (rhport + 1) % 8;
 204                         changed = 1;
 205                 }
 206         }
 207
 208         pr_info("changed %d\n", changed);
 209
 210         if ((hcd->state == HC_STATE_SUSPENDED) && (changed == 1))
 211                 usb_hcd_resume_root_hub(hcd);
 212
 213 done:
 214         spin_unlock(&vhci->lock);
 215         return changed ? retval : 0;
 216 }
 217
 218 static inline void hub_descriptor(struct usb_hub_descriptor *desc)
 219 {
 220         memset(desc, 0, sizeof(*desc));
 221         desc->bDescriptorType = 0x29;
 222         desc->bDescLength = 9;
 223         desc->wHubCharacteristics = (__force __u16)
 224                 (__constant_cpu_to_le16(0x0001));
 225         desc->bNbrPorts = VHCI_NPORTS;
 226         desc->u.hs.DeviceRemovable[0] = 0xff;
 227         desc->u.hs.DeviceRemovable[1] = 0xff;
 228 }
 229
 230 static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 231                             u16 wIndex, char *buf, u16 wLength)
 232 {
 233         struct vhci_hcd *dum;
 234         int             retval = 0;
 235         int             rhport;
 236
 237         u32 prev_port_status[VHCI_NPORTS];
 238
 239         if (!HCD_HW_ACCESSIBLE(hcd))
 240                 return -ETIMEDOUT;
 241
 242         /*
 243          * NOTE:
 244          * wIndex shows the port number and begins from 1.
 245          */
 246         usbip_dbg_vhci_rh("typeReq %x wValue %x wIndex %x\n", typeReq, wValue,
 247                           wIndex);
 248         if (wIndex > VHCI_NPORTS)
 249                 pr_err("invalid port number %d\n", wIndex);
 250         rhport = ((__u8)(wIndex & 0x00ff)) - 1;
 251
 252         dum = hcd_to_vhci(hcd);
 253
 254         spin_lock(&dum->lock);
 255
 256         /* store old status and compare now and old later */
 257         if (usbip_dbg_flag_vhci_rh) {
 258                 memcpy(prev_port_status, dum->port_status,
 259                         sizeof(prev_port_status));
 260         }
 261
 262         switch (typeReq) {
 263         case ClearHubFeature:
 264                 usbip_dbg_vhci_rh(" ClearHubFeature\n");
 265                 break;
 266         case ClearPortFeature:
 267                 switch (wValue) {
 268                 case USB_PORT_FEAT_SUSPEND:
 269                         if (dum->port_status[rhport] & USB_PORT_STAT_SUSPEND) {
 270                                 /* 20msec signaling */
 271                                 dum->resuming = 1;
 272                                 dum->re_timeout =
 273                                         jiffies + msecs_to_jiffies(20);
 274                         }
 275                         break;
 276                 case USB_PORT_FEAT_POWER:
 277                         usbip_dbg_vhci_rh(" ClearPortFeature: "
 278                                           "USB_PORT_FEAT_POWER\n");
 279                         dum->port_status[rhport] = 0;
 280                         dum->resuming = 0;
 281                         break;
 282                 case USB_PORT_FEAT_C_RESET:
 283                         usbip_dbg_vhci_rh(" ClearPortFeature: "
 284                                           "USB_PORT_FEAT_C_RESET\n");
 285                         switch (dum->vdev[rhport].speed) {
 286                         case USB_SPEED_HIGH:
 287                                 dum->port_status[rhport] |=
 288                                         USB_PORT_STAT_HIGH_SPEED;
 289                                 break;
 290                         case USB_SPEED_LOW:
 291                                 dum->port_status[rhport] |=
 292                                         USB_PORT_STAT_LOW_SPEED;
 293                                 break;
 294                         default:
 295                                 break;
 296                         }
 297                 default:
 298                         usbip_dbg_vhci_rh(" ClearPortFeature: default %x\n",
 299                                           wValue);
 300                         dum->port_status[rhport] &= ~(1 << wValue);
 301                         break;
 302                 }
 303                 break;
 304         case GetHubDescriptor:
 305                 usbip_dbg_vhci_rh(" GetHubDescriptor\n");
 306                 hub_descriptor((struct usb_hub_descriptor *) buf);
 307                 break;
 308         case GetHubStatus:
 309                 usbip_dbg_vhci_rh(" GetHubStatus\n");
 310                 *(__le32 *) buf = __constant_cpu_to_le32(0);
 311                 break;
 312         case GetPortStatus:
 313                 usbip_dbg_vhci_rh(" GetPortStatus port %x\n", wIndex);
 314                 if (wIndex > VHCI_NPORTS || wIndex < 1) {
 315                         pr_err("invalid port number %d\n", wIndex);
 316                         retval = -EPIPE;
 317                 }
 318
 319                 /* we do not care about resume. */
 320
 321                 /* whoever resets or resumes must GetPortStatus to
 322                  * complete it!!
 323                  */
 324                 if (dum->resuming && time_after(jiffies, dum->re_timeout)) {
 325                         dum->port_status[rhport] |=
 326                                 (1 << USB_PORT_FEAT_C_SUSPEND);
 327                         dum->port_status[rhport] &=
 328                                 ~(1 << USB_PORT_FEAT_SUSPEND);
 329                         dum->resuming = 0;
 330                         dum->re_timeout = 0;
 331                 }
 332
 333                 if ((dum->port_status[rhport] & (1 << USB_PORT_FEAT_RESET)) !=
 334                     0 && time_after(jiffies, dum->re_timeout)) {
 335                         dum->port_status[rhport] |=
 336                                 (1 << USB_PORT_FEAT_C_RESET);
 337                         dum->port_status[rhport] &=
 338                                 ~(1 << USB_PORT_FEAT_RESET);
 339                         dum->re_timeout = 0;
 340
 341                         if (dum->vdev[rhport].ud.status ==
 342                             VDEV_ST_NOTASSIGNED) {
 343                                 usbip_dbg_vhci_rh(" enable rhport %d "
 344                                                   "(status %u)\n",
 345                                                   rhport,
 346                                                   dum->vdev[rhport].ud.status);
 347                                 dum->port_status[rhport] |=
 348                                         USB_PORT_STAT_ENABLE;
 349                         }
 350                 }
 351                 ((u16 *) buf)[0] = cpu_to_le16(dum->port_status[rhport]);
 352                 ((u16 *) buf)[1] = cpu_to_le16(dum->port_status[rhport] >> 16);
 353
 354                 usbip_dbg_vhci_rh(" GetPortStatus bye %x %x\n", ((u16 *)buf)[0],
 355                                   ((u16 *)buf)[1]);
 356                 break;
 357         case SetHubFeature:
 358                 usbip_dbg_vhci_rh(" SetHubFeature\n");
 359                 retval = -EPIPE;
 360                 break;
 361         case SetPortFeature:
 362                 switch (wValue) {
 363                 case USB_PORT_FEAT_SUSPEND:
 364                         usbip_dbg_vhci_rh(" SetPortFeature: "
 365                                           "USB_PORT_FEAT_SUSPEND\n");
 366                         break;
 367                 case USB_PORT_FEAT_RESET:
 368                         usbip_dbg_vhci_rh(" SetPortFeature: "
 369                                           "USB_PORT_FEAT_RESET\n");
 370                         /* if it's already running, disconnect first */
 371                         if (dum->port_status[rhport] & USB_PORT_STAT_ENABLE) {
 372                                 dum->port_status[rhport] &=
 373                                         ~(USB_PORT_STAT_ENABLE |
 374                                           USB_PORT_STAT_LOW_SPEED |
 375                                           USB_PORT_STAT_HIGH_SPEED);
 376                                 /* FIXME test that code path! */
 377                         }
 378                         /* 50msec reset signaling */
 379                         dum->re_timeout = jiffies + msecs_to_jiffies(50);
 380
 381                         /* FALLTHROUGH */
 382                 default:
 383                         usbip_dbg_vhci_rh(" SetPortFeature: default %d\n",
 384                                           wValue);
 385                         dum->port_status[rhport] |= (1 << wValue);
 386                         break;
 387                 }
 388                 break;
 389
 390         default:
 391                 pr_err("default: no such request\n");
 392
 393                 /* "protocol stall" on error */
 394                 retval = -EPIPE;
 395         }
 396
 397         if (usbip_dbg_flag_vhci_rh) {
 398                 pr_debug("port %d\n", rhport);
 399                 /* Only dump valid port status */
 400                 if (rhport >= 0) {
 401                         dump_port_status_diff(prev_port_status[rhport],
 402                                               dum->port_status[rhport]);
 403                 }
 404         }
 405         usbip_dbg_vhci_rh(" bye\n");
 406
 407         spin_unlock(&dum->lock);
 408
 409         return retval;
 410 }
 411
 412 static struct vhci_device *get_vdev(struct usb_device *udev)
 413 {
 414         int i;
 415
 416         if (!udev)
 417                 return NULL;
 418
 419         for (i = 0; i < VHCI_NPORTS; i++)
 420                 if (the_controller->vdev[i].udev == udev)
 421                         return port_to_vdev(i);
 422
 423         return NULL;
 424 }
 425
 426 static void vhci_tx_urb(struct urb *urb)
 427 {
 428         struct vhci_device *vdev = get_vdev(urb->dev);
 429         struct vhci_priv *priv;
 430
 431         if (!vdev) {
 432                 pr_err("could not get virtual device");
 433                 return;
 434         }
 435
 436         priv = kzalloc(sizeof(struct vhci_priv), GFP_ATOMIC);
 437         if (!priv) {
 438                 usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
 439                 return;
 440         }
 441
 442         spin_lock(&vdev->priv_lock);
 443
 444         priv->seqnum = atomic_inc_return(&the_controller->seqnum);
 445         if (priv->seqnum == 0xffff)
 446                 dev_info(&urb->dev->dev, "seqnum max\n");
 447
 448         priv->vdev = vdev;
 449         priv->urb = urb;
 450
 451         urb->hcpriv = (void *) priv;
 452
 453         list_add_tail(&priv->list, &vdev->priv_tx);
 454
 455         wake_up(&vdev->waitq_tx);
 456         spin_unlock(&vdev->priv_lock);
 457 }
 458
 459 static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
 460                             gfp_t mem_flags)
 461 {
 462         struct device *dev = &urb->dev->dev;
 463         int ret = 0;
 464         struct vhci_device *vdev;
 465
 466         usbip_dbg_vhci_hc("enter, usb_hcd %p urb %p mem_flags %d\n",
 467                           hcd, urb, mem_flags);
 468
 469         /* patch to usb_sg_init() is in 2.5.60 */
 470         BUG_ON(!urb->transfer_buffer && urb->transfer_buffer_length);
 471
 472         spin_lock(&the_controller->lock);
 473
 474         if (urb->status != -EINPROGRESS) {
 475                 dev_err(dev, "URB already unlinked!, status %d\n", urb->status);
 476                 spin_unlock(&the_controller->lock);
 477                 return urb->status;
 478         }
 479
 480         vdev = port_to_vdev(urb->dev->portnum-1);
 481
 482         /* refuse enqueue for dead connection */
 483         spin_lock(&vdev->ud.lock);
 484         if (vdev->ud.status == VDEV_ST_NULL ||
 485             vdev->ud.status == VDEV_ST_ERROR) {
 486                 dev_err(dev, "enqueue for inactive port %d\n", vdev->rhport);
 487                 spin_unlock(&vdev->ud.lock);
 488                 spin_unlock(&the_controller->lock);
 489                 return -ENODEV;
 490         }
 491         spin_unlock(&vdev->ud.lock);
 492
 493         ret = usb_hcd_link_urb_to_ep(hcd, urb);
 494         if (ret)
 495                 goto no_need_unlink;
 496
 497         /*
 498          * The enumeration process is as follows;
 499          *
 500          *  1. Get_Descriptor request to DevAddrs(0) EndPoint(0)
 501          *     to get max packet length of default pipe
 502          *
 503          *  2. Set_Address request to DevAddr(0) EndPoint(0)
 504          *
 505          */
 506         if (usb_pipedevice(urb->pipe) == 0) {
 507                 __u8 type = usb_pipetype(urb->pipe);
 508                 struct usb_ctrlrequest *ctrlreq =
 509                         (struct usb_ctrlrequest *) urb->setup_packet;
 510
 511                 if (type != PIPE_CONTROL || !ctrlreq) {
 512                         dev_err(dev, "invalid request to devnum 0\n");
 513                         ret = -EINVAL;
 514                         goto no_need_xmit;
 515                 }
 516
 517                 switch (ctrlreq->bRequest) {
 518                 case USB_REQ_SET_ADDRESS:
 519                         /* set_address may come when a device is reset */
 520                         dev_info(dev, "SetAddress Request (%d) to port %d\n",
 521                                  ctrlreq->wValue, vdev->rhport);
 522
 523                         if (vdev->udev)
 524                                 usb_put_dev(vdev->udev);
 525                         vdev->udev = usb_get_dev(urb->dev);
 526
 527                         spin_lock(&vdev->ud.lock);
 528                         vdev->ud.status = VDEV_ST_USED;
 529                         spin_unlock(&vdev->ud.lock);
 530
 531                         if (urb->status == -EINPROGRESS) {
 532                                 /* This request is successfully completed. */
 533                                 /* If not -EINPROGRESS, possibly unlinked. */
 534                                 urb->status = 0;
 535                         }
 536
 537                         goto no_need_xmit;
 538
 539                 case USB_REQ_GET_DESCRIPTOR:
 540                         if (ctrlreq->wValue == (USB_DT_DEVICE << 8))
 541                                 usbip_dbg_vhci_hc("Not yet?: "
 542                                                   "Get_Descriptor to device 0 "
 543                                                   "(get max pipe size)\n");
 544
 545                         if (vdev->udev)
 546                                 usb_put_dev(vdev->udev);
 547                         vdev->udev = usb_get_dev(urb->dev);
 548                         goto out;
 549
 550                 default:
 551                         /* NOT REACHED */
 552                         dev_err(dev, "invalid request to devnum 0 bRequest %u, "
 553                                 "wValue %u\n", ctrlreq->bRequest,
 554                                 ctrlreq->wValue);
 555                         ret =  -EINVAL;
 556                         goto no_need_xmit;
 557                 }
 558
 559         }
 560
 561 out:
 562         vhci_tx_urb(urb);
 563         spin_unlock(&the_controller->lock);
 564
 565         return 0;
 566
 567 no_need_xmit:
 568         usb_hcd_unlink_urb_from_ep(hcd, urb);
 569 no_need_unlink:
 570         spin_unlock(&the_controller->lock);
 571         usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, urb->status);
 572         return ret;
 573 }
 574
 575 /*
 576  * vhci_rx gives back the urb after receiving the reply of the urb.  If an
 577  * unlink pdu is sent or not, vhci_rx receives a normal return pdu and gives
 578  * back its urb. For the driver unlinking the urb, the content of the urb is
 579  * not important, but the calling to its completion handler is important; the
 580  * completion of unlinking is notified by the completion handler.
 581  *
 582  *
 583  * CLIENT SIDE
 584  *
 585  * - When vhci_hcd receives RET_SUBMIT,
 586  *
 587  *      - case 1a). the urb of the pdu is not unlinking.
 588  *              - normal case
 589  *              => just give back the urb
 590  *
 591  *      - case 1b). the urb of the pdu is unlinking.
 592  *              - usbip.ko will return a reply of the unlinking request.
 593  *              => give back the urb now and go to case 2b).
 594  *
 595  * - When vhci_hcd receives RET_UNLINK,
 596  *
 597  *      - case 2a). a submit request is still pending in vhci_hcd.
 598  *              - urb was really pending in usbip.ko and urb_unlink_urb() was
 599  *                completed there.
 600  *              => free a pending submit request
 601  *              => notify unlink completeness by giving back the urb
 602  *
 603  *      - case 2b). a submit request is *not* pending in vhci_hcd.
 604  *              - urb was already given back to the core driver.
 605  *              => do not give back the urb
 606  *
 607  *
 608  * SERVER SIDE
 609  *
 610  * - When usbip receives CMD_UNLINK,
 611  *
 612  *      - case 3a). the urb of the unlink request is now in submission.
 613  *              => do usb_unlink_urb().
 614  *              => after the unlink is completed, send RET_UNLINK.
 615  *
 616  *      - case 3b). the urb of the unlink request is not in submission.
 617  *              - may be already completed or never be received
 618  *              => send RET_UNLINK
 619  *
 620  */
 621 static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 622 {
 623         struct vhci_priv *priv;
 624         struct vhci_device *vdev;
 625
 626         pr_info("dequeue a urb %p\n", urb);
 627
 628         spin_lock(&the_controller->lock);
 629
 630         priv = urb->hcpriv;
 631         if (!priv) {
 632                 /* URB was never linked! or will be soon given back by
 633                  * vhci_rx. */
 634                 spin_unlock(&the_controller->lock);
 635                 return 0;
 636         }
 637
 638         {
 639                 int ret = 0;
 640                 ret = usb_hcd_check_unlink_urb(hcd, urb, status);
 641                 if (ret) {
 642                         spin_unlock(&the_controller->lock);
 643                         return ret;
 644                 }
 645         }
 646
 647          /* send unlink request here? */
 648         vdev = priv->vdev;
 649
 650         if (!vdev->ud.tcp_socket) {
 651                 /* tcp connection is closed */
 652                 spin_lock(&vdev->priv_lock);
 653
 654                 pr_info("device %p seems to be disconnected\n", vdev);
 655                 list_del(&priv->list);
 656                 kfree(priv);
 657                 urb->hcpriv = NULL;
 658
 659                 spin_unlock(&vdev->priv_lock);
 660
 661                 /*
 662                  * If tcp connection is alive, we have sent CMD_UNLINK.
 663                  * vhci_rx will receive RET_UNLINK and give back the URB.
 664                  * Otherwise, we give back it here.
 665                  */
 666                 pr_info("gives back urb %p\n", urb);
 667
 668                 usb_hcd_unlink_urb_from_ep(hcd, urb);
 669
 670                 spin_unlock(&the_controller->lock);
 671                 usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
 672                                      urb->status);
 673                 spin_lock(&the_controller->lock);
 674
 675         } else {
 676                 /* tcp connection is alive */
 677                 struct vhci_unlink *unlink;
 678
 679                 spin_lock(&vdev->priv_lock);
 680
 681                 /* setup CMD_UNLINK pdu */
 682                 unlink = kzalloc(sizeof(struct vhci_unlink), GFP_ATOMIC);
 683                 if (!unlink) {
 684                         spin_unlock(&vdev->priv_lock);
 685                         spin_unlock(&the_controller->lock);
 686                         usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
 687                         return -ENOMEM;
 688                 }
 689
 690                 unlink->seqnum = atomic_inc_return(&the_controller->seqnum);
 691                 if (unlink->seqnum == 0xffff)
 692                         pr_info("seqnum max\n");
 693
 694                 unlink->unlink_seqnum = priv->seqnum;
 695
 696                 pr_info("device %p seems to be still connected\n", vdev);
 697
 698                 /* send cmd_unlink and try to cancel the pending URB in the
 699                  * peer */
 700                 list_add_tail(&unlink->list, &vdev->unlink_tx);
 701                 wake_up(&vdev->waitq_tx);
 702
 703                 spin_unlock(&vdev->priv_lock);
 704         }
 705
 706         spin_unlock(&the_controller->lock);
 707
 708         usbip_dbg_vhci_hc("leave\n");
 709         return 0;
 710 }
 711
 712 static void vhci_device_unlink_cleanup(struct vhci_device *vdev)
 713 {
 714         struct vhci_unlink *unlink, *tmp;
 715
 716         spin_lock(&the_controller->lock);
 717         spin_lock(&vdev->priv_lock);
 718
 719         list_for_each_entry_safe(unlink, tmp, &vdev->unlink_tx, list) {
 720                 pr_info("unlink cleanup tx %lu\n", unlink->unlink_seqnum);
 721                 list_del(&unlink->list);
 722                 kfree(unlink);
 723         }
 724
 725         while (!list_empty(&vdev->unlink_rx)) {
 726                 struct urb *urb;
 727
 728                 unlink = list_first_entry(&vdev->unlink_rx, struct vhci_unlink,
 729                         list);
 730
 731                 /* give back URB of unanswered unlink request */
 732                 pr_info("unlink cleanup rx %lu\n", unlink->unlink_seqnum);
 733
 734                 urb = pickup_urb_and_free_priv(vdev, unlink->unlink_seqnum);
 735                 if (!urb) {
 736                         pr_info("the urb (seqnum %lu) was already given back\n",
 737                                 unlink->unlink_seqnum);
 738                         list_del(&unlink->list);
 739                         kfree(unlink);
 740                         continue;
 741                 }
 742
 743                 urb->status = -ENODEV;
 744
 745                 usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
 746
 747                 list_del(&unlink->list);
 748
 749                 spin_unlock(&vdev->priv_lock);
 750                 spin_unlock(&the_controller->lock);
 751
 752                 usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
 753                                      urb->status);
 754
 755                 spin_lock(&the_controller->lock);
 756                 spin_lock(&vdev->priv_lock);
 757
 758                 kfree(unlink);
 759         }
 760
 761         spin_unlock(&vdev->priv_lock);
 762         spin_unlock(&the_controller->lock);
 763 }
 764
 765 /*
 766  * The important thing is that only one context begins cleanup.
 767  * This is why error handling and cleanup become simple.
 768  * We do not want to consider race condition as possible.
 769  */
 770 static void vhci_shutdown_connection(struct usbip_device *ud)
 771 {
 772         struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
 773
 774         /* need this? see stub_dev.c */
 775         if (ud->tcp_socket) {
 776                 pr_debug("shutdown tcp_socket %p\n", ud->tcp_socket);
 777                 kernel_sock_shutdown(ud->tcp_socket, SHUT_RDWR);
 778         }
 779
 780         /* kill threads related to this sdev */
 781         if (vdev->ud.tcp_rx) {
 782                 kthread_stop_put(vdev->ud.tcp_rx);
 783                 vdev->ud.tcp_rx = NULL;
 784         }
 785         if (vdev->ud.tcp_tx) {
 786                 kthread_stop_put(vdev->ud.tcp_tx);
 787                 vdev->ud.tcp_tx = NULL;
 788         }
 789         pr_info("stop threads\n");
 790
 791         /* active connection is closed */
 792         if (vdev->ud.tcp_socket) {
 793                 fput(vdev->ud.tcp_socket->file);
 794                 vdev->ud.tcp_socket = NULL;
 795         }
 796         pr_info("release socket\n");
 797
 798         vhci_device_unlink_cleanup(vdev);
 799
 800         /*
 801          * rh_port_disconnect() is a trigger of ...
 802          *   usb_disable_device():
 803          *      disable all the endpoints for a USB device.
 804          *   usb_disable_endpoint():
 805          *      disable endpoints. pending urbs are unlinked(dequeued).
 806          *
 807          * NOTE: After calling rh_port_disconnect(), the USB device drivers of a
 808          * detached device should release used urbs in a cleanup function (i.e.
 809          * xxx_disconnect()). Therefore, vhci_hcd does not need to release
 810          * pushed urbs and their private data in this function.
 811          *
 812          * NOTE: vhci_dequeue() must be considered carefully. When shutting down
 813          * a connection, vhci_shutdown_connection() expects vhci_dequeue()
 814          * gives back pushed urbs and frees their private data by request of
 815          * the cleanup function of a USB driver. When unlinking a urb with an
 816          * active connection, vhci_dequeue() does not give back the urb which
 817          * is actually given back by vhci_rx after receiving its return pdu.
 818          *
 819          */
 820         rh_port_disconnect(vdev->rhport);
 821
 822         pr_info("disconnect device\n");
 823 }
 824
 825
 826 static void vhci_device_reset(struct usbip_device *ud)
 827 {
 828         struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
 829
 830         spin_lock(&ud->lock);
 831
 832         vdev->speed  = 0;
 833         vdev->devid  = 0;
 834
 835         if (vdev->udev)
 836                 usb_put_dev(vdev->udev);
 837         vdev->udev = NULL;
 838
 839         if (ud->tcp_socket) {
 840                 fput(ud->tcp_socket->file);
 841                 ud->tcp_socket = NULL;
 842         }
 843         ud->status = VDEV_ST_NULL;
 844
 845         spin_unlock(&ud->lock);
 846 }
 847
 848 static void vhci_device_unusable(struct usbip_device *ud)
 849 {
 850         spin_lock(&ud->lock);
 851         ud->status = VDEV_ST_ERROR;
 852         spin_unlock(&ud->lock);
 853 }
 854
 855 static void vhci_device_init(struct vhci_device *vdev)
 856 {
 857         memset(vdev, 0, sizeof(*vdev));
 858
 859         vdev->ud.side   = USBIP_VHCI;
 860         vdev->ud.status = VDEV_ST_NULL;
 861         spin_lock_init(&vdev->ud.lock);
 862
 863         INIT_LIST_HEAD(&vdev->priv_rx);
 864         INIT_LIST_HEAD(&vdev->priv_tx);
 865         INIT_LIST_HEAD(&vdev->unlink_tx);
 866         INIT_LIST_HEAD(&vdev->unlink_rx);
 867         spin_lock_init(&vdev->priv_lock);
 868
 869         init_waitqueue_head(&vdev->waitq_tx);
 870
 871         vdev->ud.eh_ops.shutdown = vhci_shutdown_connection;
 872         vdev->ud.eh_ops.reset = vhci_device_reset;
 873         vdev->ud.eh_ops.unusable = vhci_device_unusable;
 874
 875         usbip_start_eh(&vdev->ud);
 876 }
 877
 878 static int vhci_start(struct usb_hcd *hcd)
 879 {
 880         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
 881         int rhport;
 882         int err = 0;
 883
 884         usbip_dbg_vhci_hc("enter vhci_start\n");
 885
 886         /* initialize private data of usb_hcd */
 887
 888         for (rhport = 0; rhport < VHCI_NPORTS; rhport++) {
 889                 struct vhci_device *vdev = &vhci->vdev[rhport];
 890                 vhci_device_init(vdev);
 891                 vdev->rhport = rhport;
 892         }
 893
 894         atomic_set(&vhci->seqnum, 0);
 895         spin_lock_init(&vhci->lock);
 896
 897         hcd->power_budget = 0; /* no limit */
 898         hcd->uses_new_polling = 1;
 899
 900         /* vhci_hcd is now ready to be controlled through sysfs */
 901         err = sysfs_create_group(&vhci_dev(vhci)->kobj, &dev_attr_group);
 902         if (err) {
 903                 pr_err("create sysfs files\n");
 904                 return err;
 905         }
 906
 907         return 0;
 908 }
 909
 910 static void vhci_stop(struct usb_hcd *hcd)
 911 {
 912         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
 913         int rhport = 0;
 914
 915         usbip_dbg_vhci_hc("stop VHCI controller\n");
 916
 917         /* 1. remove the userland interface of vhci_hcd */
 918         sysfs_remove_group(&vhci_dev(vhci)->kobj, &dev_attr_group);
 919
 920         /* 2. shutdown all the ports of vhci_hcd */
 921         for (rhport = 0 ; rhport < VHCI_NPORTS; rhport++) {
 922                 struct vhci_device *vdev = &vhci->vdev[rhport];
 923
 924                 usbip_event_add(&vdev->ud, VDEV_EVENT_REMOVED);
 925                 usbip_stop_eh(&vdev->ud);
 926         }
 927 }
 928
 929 static int vhci_get_frame_number(struct usb_hcd *hcd)
 930 {
 931         pr_err("Not yet implemented\n");
 932         return 0;
 933 }
 934
 935 #ifdef CONFIG_PM
 936
 937 /* FIXME: suspend/resume */
 938 static int vhci_bus_suspend(struct usb_hcd *hcd)
 939 {
 940         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
 941
 942         dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
 943
 944         spin_lock(&vhci->lock);
 945         hcd->state = HC_STATE_SUSPENDED;
 946         spin_unlock(&vhci->lock);
 947
 948         return 0;
 949 }
 950
 951 static int vhci_bus_resume(struct usb_hcd *hcd)
 952 {
 953         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
 954         int rc = 0;
 955
 956         dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
 957
 958         spin_lock(&vhci->lock);
 959         if (!HCD_HW_ACCESSIBLE(hcd))
 960                 rc = -ESHUTDOWN;
 961         else
 962                 hcd->state = HC_STATE_RUNNING;
 963         spin_unlock(&vhci->lock);
 964
 965         return rc;
 966 }
 967
 968 #else
 969
 970 #define vhci_bus_suspend      NULL
 971 #define vhci_bus_resume       NULL
 972 #endif
 973
 974 static struct hc_driver vhci_hc_driver = {
 975         .description    = driver_name,
 976         .product_desc   = driver_desc,
 977         .hcd_priv_size  = sizeof(struct vhci_hcd),
 978
 979         .flags          = HCD_USB2,
 980
 981         .start          = vhci_start,
 982         .stop           = vhci_stop,
 983
 984         .urb_enqueue    = vhci_urb_enqueue,
 985         .urb_dequeue    = vhci_urb_dequeue,
 986
 987         .get_frame_number = vhci_get_frame_number,
 988
 989         .hub_status_data = vhci_hub_status,
 990         .hub_control    = vhci_hub_control,
 991         .bus_suspend    = vhci_bus_suspend,
 992         .bus_resume     = vhci_bus_resume,
 993 };
 994
 995 static int vhci_hcd_probe(struct platform_device *pdev)
 996 {
 997         struct usb_hcd          *hcd;
 998         int                     ret;
 999
1000         usbip_dbg_vhci_hc("name %s id %d\n", pdev->name, pdev->id);
1001
1002         /* will be removed */
1003         if (pdev->dev.dma_mask) {
1004                 dev_info(&pdev->dev, "vhci_hcd DMA not supported\n");
1005                 return -EINVAL;
1006         }
1007
1008         /*
1009          * Allocate and initialize hcd.
1010          * Our private data is also allocated automatically.
1011          */
1012         hcd = usb_create_hcd(&vhci_hc_driver, &pdev->dev, dev_name(&pdev->dev));
1013         if (!hcd) {
1014                 pr_err("create hcd failed\n");
1015                 return -ENOMEM;
1016         }
1017         hcd->has_tt = 1;
1018
1019         /* this is private data for vhci_hcd */
1020         the_controller = hcd_to_vhci(hcd);
1021
1022         /*
1023          * Finish generic HCD structure initialization and register.
1024          * Call the driver's reset() and start() routines.
1025          */
1026         ret = usb_add_hcd(hcd, 0, 0);
1027         if (ret != 0) {
1028                 pr_err("usb_add_hcd failed %d\n", ret);
1029                 usb_put_hcd(hcd);
1030                 the_controller = NULL;
1031                 return ret;
1032         }
1033
1034         usbip_dbg_vhci_hc("bye\n");
1035         return 0;
1036 }
1037
1038 static int vhci_hcd_remove(struct platform_device *pdev)
1039 {
1040         struct usb_hcd  *hcd;
1041
1042         hcd = platform_get_drvdata(pdev);
1043         if (!hcd)
1044                 return 0;
1045
1046         /*
1047          * Disconnects the root hub,
1048          * then reverses the effects of usb_add_hcd(),
1049          * invoking the HCD's stop() methods.
1050          */
1051         usb_remove_hcd(hcd);
1052         usb_put_hcd(hcd);
1053         the_controller = NULL;
1054
1055         return 0;
1056 }
1057
1058 #ifdef CONFIG_PM
1059
1060 /* what should happen for USB/IP under suspend/resume? */
1061 static int vhci_hcd_suspend(struct platform_device *pdev, pm_message_t state)
1062 {
1063         struct usb_hcd *hcd;
1064         int rhport = 0;
1065         int connected = 0;
1066         int ret = 0;
1067
1068         hcd = platform_get_drvdata(pdev);
1069
1070         spin_lock(&the_controller->lock);
1071
1072         for (rhport = 0; rhport < VHCI_NPORTS; rhport++)
1073                 if (the_controller->port_status[rhport] &
1074                     USB_PORT_STAT_CONNECTION)
1075                         connected += 1;
1076
1077         spin_unlock(&the_controller->lock);
1078
1079         if (connected > 0) {
1080                 dev_info(&pdev->dev, "We have %d active connection%s. Do not "
1081                          "suspend.\n", connected, (connected == 1 ? "" : "s"));
1082                 ret =  -EBUSY;
1083         } else {
1084                 dev_info(&pdev->dev, "suspend vhci_hcd");
1085                 clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1086         }
1087
1088         return ret;
1089 }
1090
1091 static int vhci_hcd_resume(struct platform_device *pdev)
1092 {
1093         struct usb_hcd *hcd;
1094
1095         dev_dbg(&pdev->dev, "%s\n", __func__);
1096
1097         hcd = platform_get_drvdata(pdev);
1098         set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1099         usb_hcd_poll_rh_status(hcd);
1100
1101         return 0;
1102 }
1103
1104 #else
1105
1106 #define vhci_hcd_suspend        NULL
1107 #define vhci_hcd_resume         NULL
1108
1109 #endif
1110
1111 static struct platform_driver vhci_driver = {
1112         .probe  = vhci_hcd_probe,
1113         .remove = vhci_hcd_remove,
1114         .suspend = vhci_hcd_suspend,
1115         .resume = vhci_hcd_resume,
1116         .driver = {
1117                 .name = (char *) driver_name,
1118                 .owner = THIS_MODULE,
1119         },
1120 };
1121
1122 /*
1123  * The VHCI 'device' is 'virtual'; not a real plug&play hardware.
1124  * We need to add this virtual device as a platform device arbitrarily:
1125  *      1. platform_device_register()
1126  */
1127 static void the_pdev_release(struct device *dev)
1128 {
1129         return;
1130 }
1131
1132 static struct platform_device the_pdev = {
1133         /* should be the same name as driver_name */
1134         .name = (char *) driver_name,
1135         .id = -1,
1136         .dev = {
1137                 .release = the_pdev_release,
1138         },
1139 };
1140
1141 static int __init vhci_hcd_init(void)
1142 {
1143         int ret;
1144
1145         if (usb_disabled())
1146                 return -ENODEV;
1147
1148         ret = platform_driver_register(&vhci_driver);
1149         if (ret < 0)
1150                 goto err_driver_register;
1151
1152         ret = platform_device_register(&the_pdev);
1153         if (ret < 0)
1154                 goto err_platform_device_register;
1155
1156         pr_info(DRIVER_DESC " v" USBIP_VERSION "\n");
1157         return ret;
1158
1159 err_platform_device_register:
1160         platform_driver_unregister(&vhci_driver);
1161 err_driver_register:
1162         return ret;
1163 }
1164
1165 static void __exit vhci_hcd_exit(void)
1166 {
1167         platform_device_unregister(&the_pdev);
1168         platform_driver_unregister(&vhci_driver);
1169 }
1170
1171 module_init(vhci_hcd_init);
1172 module_exit(vhci_hcd_exit);
1173
1174 MODULE_AUTHOR(DRIVER_AUTHOR);
1175 MODULE_DESCRIPTION(DRIVER_DESC);
1176 MODULE_LICENSE("GPL");
1177 MODULE_VERSION(USBIP_VERSION);