git.oblomov.eu Git - linux-2.6/blob - drivers/firewire/fw-cdev.c

   1 /*
   2  * Char device for device raw access
   3  *
   4  * Copyright (C) 2005-2007  Kristian Hoegsberg <krh@bitplanet.net>
   5  *
   6  * This program 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 program 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 Foundation,
  18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/kernel.h>
  23 #include <linux/wait.h>
  24 #include <linux/errno.h>
  25 #include <linux/device.h>
  26 #include <linux/vmalloc.h>
  27 #include <linux/poll.h>
  28 #include <linux/preempt.h>
  29 #include <linux/time.h>
  30 #include <linux/delay.h>
  31 #include <linux/mm.h>
  32 #include <linux/idr.h>
  33 #include <linux/compat.h>
  34 #include <linux/firewire-cdev.h>
  35 #include <asm/system.h>
  36 #include <asm/uaccess.h>
  37 #include "fw-transaction.h"
  38 #include "fw-topology.h"
  39 #include "fw-device.h"
  40
  41 struct client;
  42 struct client_resource {
  43         struct list_head link;
  44         void (*release)(struct client *client, struct client_resource *r);
  45         u32 handle;
  46 };
  47
  48 /*
  49  * dequeue_event() just kfree()'s the event, so the event has to be
  50  * the first field in the struct.
  51  */
  52
  53 struct event {
  54         struct { void *data; size_t size; } v[2];
  55         struct list_head link;
  56 };
  57
  58 struct bus_reset {
  59         struct event event;
  60         struct fw_cdev_event_bus_reset reset;
  61 };
  62
  63 struct response {
  64         struct event event;
  65         struct fw_transaction transaction;
  66         struct client *client;
  67         struct client_resource resource;
  68         struct fw_cdev_event_response response;
  69 };
  70
  71 struct iso_interrupt {
  72         struct event event;
  73         struct fw_cdev_event_iso_interrupt interrupt;
  74 };
  75
  76 struct client {
  77         u32 version;
  78         struct fw_device *device;
  79         spinlock_t lock;
  80         u32 resource_handle;
  81         struct list_head resource_list;
  82         struct list_head event_list;
  83         wait_queue_head_t wait;
  84         u64 bus_reset_closure;
  85
  86         struct fw_iso_context *iso_context;
  87         u64 iso_closure;
  88         struct fw_iso_buffer buffer;
  89         unsigned long vm_start;
  90
  91         struct list_head link;
  92 };
  93
  94 static inline void __user *
  95 u64_to_uptr(__u64 value)
  96 {
  97         return (void __user *)(unsigned long)value;
  98 }
  99
 100 static inline __u64
 101 uptr_to_u64(void __user *ptr)
 102 {
 103         return (__u64)(unsigned long)ptr;
 104 }
 105
 106 static int fw_device_op_open(struct inode *inode, struct file *file)
 107 {
 108         struct fw_device *device;
 109         struct client *client;
 110         unsigned long flags;
 111
 112         device = fw_device_get_by_devt(inode->i_rdev);
 113         if (device == NULL)
 114                 return -ENODEV;
 115
 116         client = kzalloc(sizeof(*client), GFP_KERNEL);
 117         if (client == NULL) {
 118                 fw_device_put(device);
 119                 return -ENOMEM;
 120         }
 121
 122         client->device = device;
 123         INIT_LIST_HEAD(&client->event_list);
 124         INIT_LIST_HEAD(&client->resource_list);
 125         spin_lock_init(&client->lock);
 126         init_waitqueue_head(&client->wait);
 127
 128         file->private_data = client;
 129
 130         spin_lock_irqsave(&device->card->lock, flags);
 131         list_add_tail(&client->link, &device->client_list);
 132         spin_unlock_irqrestore(&device->card->lock, flags);
 133
 134         return 0;
 135 }
 136
 137 static void queue_event(struct client *client, struct event *event,
 138                         void *data0, size_t size0, void *data1, size_t size1)
 139 {
 140         unsigned long flags;
 141
 142         event->v[0].data = data0;
 143         event->v[0].size = size0;
 144         event->v[1].data = data1;
 145         event->v[1].size = size1;
 146
 147         spin_lock_irqsave(&client->lock, flags);
 148         list_add_tail(&event->link, &client->event_list);
 149         spin_unlock_irqrestore(&client->lock, flags);
 150
 151         wake_up_interruptible(&client->wait);
 152 }
 153
 154 static int
 155 dequeue_event(struct client *client, char __user *buffer, size_t count)
 156 {
 157         unsigned long flags;
 158         struct event *event;
 159         size_t size, total;
 160         int i, retval;
 161
 162         retval = wait_event_interruptible(client->wait,
 163                                           !list_empty(&client->event_list) ||
 164                                           fw_device_is_shutdown(client->device));
 165         if (retval < 0)
 166                 return retval;
 167
 168         if (list_empty(&client->event_list) &&
 169                        fw_device_is_shutdown(client->device))
 170                 return -ENODEV;
 171
 172         spin_lock_irqsave(&client->lock, flags);
 173         event = container_of(client->event_list.next, struct event, link);
 174         list_del(&event->link);
 175         spin_unlock_irqrestore(&client->lock, flags);
 176
 177         total = 0;
 178         for (i = 0; i < ARRAY_SIZE(event->v) && total < count; i++) {
 179                 size = min(event->v[i].size, count - total);
 180                 if (copy_to_user(buffer + total, event->v[i].data, size)) {
 181                         retval = -EFAULT;
 182                         goto out;
 183                 }
 184                 total += size;
 185         }
 186         retval = total;
 187
 188  out:
 189         kfree(event);
 190
 191         return retval;
 192 }
 193
 194 static ssize_t
 195 fw_device_op_read(struct file *file,
 196                   char __user *buffer, size_t count, loff_t *offset)
 197 {
 198         struct client *client = file->private_data;
 199
 200         return dequeue_event(client, buffer, count);
 201 }
 202
 203 static void
 204 fill_bus_reset_event(struct fw_cdev_event_bus_reset *event,
 205                      struct client *client)
 206 {
 207         struct fw_card *card = client->device->card;
 208
 209         event->closure       = client->bus_reset_closure;
 210         event->type          = FW_CDEV_EVENT_BUS_RESET;
 211         event->generation    = client->device->generation;
 212         smp_rmb();           /* node_id must not be older than generation */
 213         event->node_id       = client->device->node_id;
 214         event->local_node_id = card->local_node->node_id;
 215         event->bm_node_id    = 0; /* FIXME: We don't track the BM. */
 216         event->irm_node_id   = card->irm_node->node_id;
 217         event->root_node_id  = card->root_node->node_id;
 218 }
 219
 220 static void
 221 for_each_client(struct fw_device *device,
 222                 void (*callback)(struct client *client))
 223 {
 224         struct fw_card *card = device->card;
 225         struct client *c;
 226         unsigned long flags;
 227
 228         spin_lock_irqsave(&card->lock, flags);
 229
 230         list_for_each_entry(c, &device->client_list, link)
 231                 callback(c);
 232
 233         spin_unlock_irqrestore(&card->lock, flags);
 234 }
 235
 236 static void
 237 queue_bus_reset_event(struct client *client)
 238 {
 239         struct bus_reset *bus_reset;
 240
 241         bus_reset = kzalloc(sizeof(*bus_reset), GFP_ATOMIC);
 242         if (bus_reset == NULL) {
 243                 fw_notify("Out of memory when allocating bus reset event\n");
 244                 return;
 245         }
 246
 247         fill_bus_reset_event(&bus_reset->reset, client);
 248
 249         queue_event(client, &bus_reset->event,
 250                     &bus_reset->reset, sizeof(bus_reset->reset), NULL, 0);
 251 }
 252
 253 void fw_device_cdev_update(struct fw_device *device)
 254 {
 255         for_each_client(device, queue_bus_reset_event);
 256 }
 257
 258 static void wake_up_client(struct client *client)
 259 {
 260         wake_up_interruptible(&client->wait);
 261 }
 262
 263 void fw_device_cdev_remove(struct fw_device *device)
 264 {
 265         for_each_client(device, wake_up_client);
 266 }
 267
 268 static int ioctl_get_info(struct client *client, void *buffer)
 269 {
 270         struct fw_cdev_get_info *get_info = buffer;
 271         struct fw_cdev_event_bus_reset bus_reset;
 272         unsigned long ret = 0;
 273
 274         client->version = get_info->version;
 275         get_info->version = FW_CDEV_VERSION;
 276
 277         down_read(&fw_device_rwsem);
 278
 279         if (get_info->rom != 0) {
 280                 void __user *uptr = u64_to_uptr(get_info->rom);
 281                 size_t want = get_info->rom_length;
 282                 size_t have = client->device->config_rom_length * 4;
 283
 284                 ret = copy_to_user(uptr, client->device->config_rom,
 285                                    min(want, have));
 286         }
 287         get_info->rom_length = client->device->config_rom_length * 4;
 288
 289         up_read(&fw_device_rwsem);
 290
 291         if (ret != 0)
 292                 return -EFAULT;
 293
 294         client->bus_reset_closure = get_info->bus_reset_closure;
 295         if (get_info->bus_reset != 0) {
 296                 void __user *uptr = u64_to_uptr(get_info->bus_reset);
 297
 298                 fill_bus_reset_event(&bus_reset, client);
 299                 if (copy_to_user(uptr, &bus_reset, sizeof(bus_reset)))
 300                         return -EFAULT;
 301         }
 302
 303         get_info->card = client->device->card->index;
 304
 305         return 0;
 306 }
 307
 308 static void
 309 add_client_resource(struct client *client, struct client_resource *resource)
 310 {
 311         unsigned long flags;
 312
 313         spin_lock_irqsave(&client->lock, flags);
 314         list_add_tail(&resource->link, &client->resource_list);
 315         resource->handle = client->resource_handle++;
 316         spin_unlock_irqrestore(&client->lock, flags);
 317 }
 318
 319 static int
 320 release_client_resource(struct client *client, u32 handle,
 321                         struct client_resource **resource)
 322 {
 323         struct client_resource *r;
 324         unsigned long flags;
 325
 326         spin_lock_irqsave(&client->lock, flags);
 327         list_for_each_entry(r, &client->resource_list, link) {
 328                 if (r->handle == handle) {
 329                         list_del(&r->link);
 330                         break;
 331                 }
 332         }
 333         spin_unlock_irqrestore(&client->lock, flags);
 334
 335         if (&r->link == &client->resource_list)
 336                 return -EINVAL;
 337
 338         if (resource)
 339                 *resource = r;
 340         else
 341                 r->release(client, r);
 342
 343         return 0;
 344 }
 345
 346 static void
 347 release_transaction(struct client *client, struct client_resource *resource)
 348 {
 349         struct response *response =
 350                 container_of(resource, struct response, resource);
 351
 352         fw_cancel_transaction(client->device->card, &response->transaction);
 353 }
 354
 355 static void
 356 complete_transaction(struct fw_card *card, int rcode,
 357                      void *payload, size_t length, void *data)
 358 {
 359         struct response *response = data;
 360         struct client *client = response->client;
 361         unsigned long flags;
 362
 363         if (length < response->response.length)
 364                 response->response.length = length;
 365         if (rcode == RCODE_COMPLETE)
 366                 memcpy(response->response.data, payload,
 367                        response->response.length);
 368
 369         spin_lock_irqsave(&client->lock, flags);
 370         list_del(&response->resource.link);
 371         spin_unlock_irqrestore(&client->lock, flags);
 372
 373         response->response.type   = FW_CDEV_EVENT_RESPONSE;
 374         response->response.rcode  = rcode;
 375         queue_event(client, &response->event,
 376                     &response->response, sizeof(response->response),
 377                     response->response.data, response->response.length);
 378 }
 379
 380 static int ioctl_send_request(struct client *client, void *buffer)
 381 {
 382         struct fw_device *device = client->device;
 383         struct fw_cdev_send_request *request = buffer;
 384         struct response *response;
 385
 386         /* What is the biggest size we'll accept, really? */
 387         if (request->length > 4096)
 388                 return -EINVAL;
 389
 390         response = kmalloc(sizeof(*response) + request->length, GFP_KERNEL);
 391         if (response == NULL)
 392                 return -ENOMEM;
 393
 394         response->client = client;
 395         response->response.length = request->length;
 396         response->response.closure = request->closure;
 397
 398         if (request->data &&
 399             copy_from_user(response->response.data,
 400                            u64_to_uptr(request->data), request->length)) {
 401                 kfree(response);
 402                 return -EFAULT;
 403         }
 404
 405         response->resource.release = release_transaction;
 406         add_client_resource(client, &response->resource);
 407
 408         fw_send_request(device->card, &response->transaction,
 409                         request->tcode & 0x1f,
 410                         device->node->node_id,
 411                         request->generation,
 412                         device->max_speed,
 413                         request->offset,
 414                         response->response.data, request->length,
 415                         complete_transaction, response);
 416
 417         if (request->data)
 418                 return sizeof(request) + request->length;
 419         else
 420                 return sizeof(request);
 421 }
 422
 423 struct address_handler {
 424         struct fw_address_handler handler;
 425         __u64 closure;
 426         struct client *client;
 427         struct client_resource resource;
 428 };
 429
 430 struct request {
 431         struct fw_request *request;
 432         void *data;
 433         size_t length;
 434         struct client_resource resource;
 435 };
 436
 437 struct request_event {
 438         struct event event;
 439         struct fw_cdev_event_request request;
 440 };
 441
 442 static void
 443 release_request(struct client *client, struct client_resource *resource)
 444 {
 445         struct request *request =
 446                 container_of(resource, struct request, resource);
 447
 448         fw_send_response(client->device->card, request->request,
 449                          RCODE_CONFLICT_ERROR);
 450         kfree(request);
 451 }
 452
 453 static void
 454 handle_request(struct fw_card *card, struct fw_request *r,
 455                int tcode, int destination, int source,
 456                int generation, int speed,
 457                unsigned long long offset,
 458                void *payload, size_t length, void *callback_data)
 459 {
 460         struct address_handler *handler = callback_data;
 461         struct request *request;
 462         struct request_event *e;
 463         struct client *client = handler->client;
 464
 465         request = kmalloc(sizeof(*request), GFP_ATOMIC);
 466         e = kmalloc(sizeof(*e), GFP_ATOMIC);
 467         if (request == NULL || e == NULL) {
 468                 kfree(request);
 469                 kfree(e);
 470                 fw_send_response(card, r, RCODE_CONFLICT_ERROR);
 471                 return;
 472         }
 473
 474         request->request = r;
 475         request->data    = payload;
 476         request->length  = length;
 477
 478         request->resource.release = release_request;
 479         add_client_resource(client, &request->resource);
 480
 481         e->request.type    = FW_CDEV_EVENT_REQUEST;
 482         e->request.tcode   = tcode;
 483         e->request.offset  = offset;
 484         e->request.length  = length;
 485         e->request.handle  = request->resource.handle;
 486         e->request.closure = handler->closure;
 487
 488         queue_event(client, &e->event,
 489                     &e->request, sizeof(e->request), payload, length);
 490 }
 491
 492 static void
 493 release_address_handler(struct client *client,
 494                         struct client_resource *resource)
 495 {
 496         struct address_handler *handler =
 497                 container_of(resource, struct address_handler, resource);
 498
 499         fw_core_remove_address_handler(&handler->handler);
 500         kfree(handler);
 501 }
 502
 503 static int ioctl_allocate(struct client *client, void *buffer)
 504 {
 505         struct fw_cdev_allocate *request = buffer;
 506         struct address_handler *handler;
 507         struct fw_address_region region;
 508
 509         handler = kmalloc(sizeof(*handler), GFP_KERNEL);
 510         if (handler == NULL)
 511                 return -ENOMEM;
 512
 513         region.start = request->offset;
 514         region.end = request->offset + request->length;
 515         handler->handler.length = request->length;
 516         handler->handler.address_callback = handle_request;
 517         handler->handler.callback_data = handler;
 518         handler->closure = request->closure;
 519         handler->client = client;
 520
 521         if (fw_core_add_address_handler(&handler->handler, &region) < 0) {
 522                 kfree(handler);
 523                 return -EBUSY;
 524         }
 525
 526         handler->resource.release = release_address_handler;
 527         add_client_resource(client, &handler->resource);
 528         request->handle = handler->resource.handle;
 529
 530         return 0;
 531 }
 532
 533 static int ioctl_deallocate(struct client *client, void *buffer)
 534 {
 535         struct fw_cdev_deallocate *request = buffer;
 536
 537         return release_client_resource(client, request->handle, NULL);
 538 }
 539
 540 static int ioctl_send_response(struct client *client, void *buffer)
 541 {
 542         struct fw_cdev_send_response *request = buffer;
 543         struct client_resource *resource;
 544         struct request *r;
 545
 546         if (release_client_resource(client, request->handle, &resource) < 0)
 547                 return -EINVAL;
 548         r = container_of(resource, struct request, resource);
 549         if (request->length < r->length)
 550                 r->length = request->length;
 551         if (copy_from_user(r->data, u64_to_uptr(request->data), r->length))
 552                 return -EFAULT;
 553
 554         fw_send_response(client->device->card, r->request, request->rcode);
 555         kfree(r);
 556
 557         return 0;
 558 }
 559
 560 static int ioctl_initiate_bus_reset(struct client *client, void *buffer)
 561 {
 562         struct fw_cdev_initiate_bus_reset *request = buffer;
 563         int short_reset;
 564
 565         short_reset = (request->type == FW_CDEV_SHORT_RESET);
 566
 567         return fw_core_initiate_bus_reset(client->device->card, short_reset);
 568 }
 569
 570 struct descriptor {
 571         struct fw_descriptor d;
 572         struct client_resource resource;
 573         u32 data[0];
 574 };
 575
 576 static void release_descriptor(struct client *client,
 577                                struct client_resource *resource)
 578 {
 579         struct descriptor *descriptor =
 580                 container_of(resource, struct descriptor, resource);
 581
 582         fw_core_remove_descriptor(&descriptor->d);
 583         kfree(descriptor);
 584 }
 585
 586 static int ioctl_add_descriptor(struct client *client, void *buffer)
 587 {
 588         struct fw_cdev_add_descriptor *request = buffer;
 589         struct descriptor *descriptor;
 590         int retval;
 591
 592         if (request->length > 256)
 593                 return -EINVAL;
 594
 595         descriptor =
 596                 kmalloc(sizeof(*descriptor) + request->length * 4, GFP_KERNEL);
 597         if (descriptor == NULL)
 598                 return -ENOMEM;
 599
 600         if (copy_from_user(descriptor->data,
 601                            u64_to_uptr(request->data), request->length * 4)) {
 602                 kfree(descriptor);
 603                 return -EFAULT;
 604         }
 605
 606         descriptor->d.length = request->length;
 607         descriptor->d.immediate = request->immediate;
 608         descriptor->d.key = request->key;
 609         descriptor->d.data = descriptor->data;
 610
 611         retval = fw_core_add_descriptor(&descriptor->d);
 612         if (retval < 0) {
 613                 kfree(descriptor);
 614                 return retval;
 615         }
 616
 617         descriptor->resource.release = release_descriptor;
 618         add_client_resource(client, &descriptor->resource);
 619         request->handle = descriptor->resource.handle;
 620
 621         return 0;
 622 }
 623
 624 static int ioctl_remove_descriptor(struct client *client, void *buffer)
 625 {
 626         struct fw_cdev_remove_descriptor *request = buffer;
 627
 628         return release_client_resource(client, request->handle, NULL);
 629 }
 630
 631 static void
 632 iso_callback(struct fw_iso_context *context, u32 cycle,
 633              size_t header_length, void *header, void *data)
 634 {
 635         struct client *client = data;
 636         struct iso_interrupt *irq;
 637
 638         irq = kzalloc(sizeof(*irq) + header_length, GFP_ATOMIC);
 639         if (irq == NULL)
 640                 return;
 641
 642         irq->interrupt.type      = FW_CDEV_EVENT_ISO_INTERRUPT;
 643         irq->interrupt.closure   = client->iso_closure;
 644         irq->interrupt.cycle     = cycle;
 645         irq->interrupt.header_length = header_length;
 646         memcpy(irq->interrupt.header, header, header_length);
 647         queue_event(client, &irq->event, &irq->interrupt,
 648                     sizeof(irq->interrupt) + header_length, NULL, 0);
 649 }
 650
 651 static int ioctl_create_iso_context(struct client *client, void *buffer)
 652 {
 653         struct fw_cdev_create_iso_context *request = buffer;
 654         struct fw_iso_context *context;
 655
 656         /* We only support one context at this time. */
 657         if (client->iso_context != NULL)
 658                 return -EBUSY;
 659
 660         if (request->channel > 63)
 661                 return -EINVAL;
 662
 663         switch (request->type) {
 664         case FW_ISO_CONTEXT_RECEIVE:
 665                 if (request->header_size < 4 || (request->header_size & 3))
 666                         return -EINVAL;
 667
 668                 break;
 669
 670         case FW_ISO_CONTEXT_TRANSMIT:
 671                 if (request->speed > SCODE_3200)
 672                         return -EINVAL;
 673
 674                 break;
 675
 676         default:
 677                 return -EINVAL;
 678         }
 679
 680         context =  fw_iso_context_create(client->device->card,
 681                                          request->type,
 682                                          request->channel,
 683                                          request->speed,
 684                                          request->header_size,
 685                                          iso_callback, client);
 686         if (IS_ERR(context))
 687                 return PTR_ERR(context);
 688
 689         client->iso_closure = request->closure;
 690         client->iso_context = context;
 691
 692         /* We only support one context at this time. */
 693         request->handle = 0;
 694
 695         return 0;
 696 }
 697
 698 /* Macros for decoding the iso packet control header. */
 699 #define GET_PAYLOAD_LENGTH(v)   ((v) & 0xffff)
 700 #define GET_INTERRUPT(v)        (((v) >> 16) & 0x01)
 701 #define GET_SKIP(v)             (((v) >> 17) & 0x01)
 702 #define GET_TAG(v)              (((v) >> 18) & 0x02)
 703 #define GET_SY(v)               (((v) >> 20) & 0x04)
 704 #define GET_HEADER_LENGTH(v)    (((v) >> 24) & 0xff)
 705
 706 static int ioctl_queue_iso(struct client *client, void *buffer)
 707 {
 708         struct fw_cdev_queue_iso *request = buffer;
 709         struct fw_cdev_iso_packet __user *p, *end, *next;
 710         struct fw_iso_context *ctx = client->iso_context;
 711         unsigned long payload, buffer_end, header_length;
 712         u32 control;
 713         int count;
 714         struct {
 715                 struct fw_iso_packet packet;
 716                 u8 header[256];
 717         } u;
 718
 719         if (ctx == NULL || request->handle != 0)
 720                 return -EINVAL;
 721
 722         /*
 723          * If the user passes a non-NULL data pointer, has mmap()'ed
 724          * the iso buffer, and the pointer points inside the buffer,
 725          * we setup the payload pointers accordingly.  Otherwise we
 726          * set them both to 0, which will still let packets with
 727          * payload_length == 0 through.  In other words, if no packets
 728          * use the indirect payload, the iso buffer need not be mapped
 729          * and the request->data pointer is ignored.
 730          */
 731
 732         payload = (unsigned long)request->data - client->vm_start;
 733         buffer_end = client->buffer.page_count << PAGE_SHIFT;
 734         if (request->data == 0 || client->buffer.pages == NULL ||
 735             payload >= buffer_end) {
 736                 payload = 0;
 737                 buffer_end = 0;
 738         }
 739
 740         p = (struct fw_cdev_iso_packet __user *)u64_to_uptr(request->packets);
 741
 742         if (!access_ok(VERIFY_READ, p, request->size))
 743                 return -EFAULT;
 744
 745         end = (void __user *)p + request->size;
 746         count = 0;
 747         while (p < end) {
 748                 if (get_user(control, &p->control))
 749                         return -EFAULT;
 750                 u.packet.payload_length = GET_PAYLOAD_LENGTH(control);
 751                 u.packet.interrupt = GET_INTERRUPT(control);
 752                 u.packet.skip = GET_SKIP(control);
 753                 u.packet.tag = GET_TAG(control);
 754                 u.packet.sy = GET_SY(control);
 755                 u.packet.header_length = GET_HEADER_LENGTH(control);
 756
 757                 if (ctx->type == FW_ISO_CONTEXT_TRANSMIT) {
 758                         header_length = u.packet.header_length;
 759                 } else {
 760                         /*
 761                          * We require that header_length is a multiple of
 762                          * the fixed header size, ctx->header_size.
 763                          */
 764                         if (ctx->header_size == 0) {
 765                                 if (u.packet.header_length > 0)
 766                                         return -EINVAL;
 767                         } else if (u.packet.header_length % ctx->header_size != 0) {
 768                                 return -EINVAL;
 769                         }
 770                         header_length = 0;
 771                 }
 772
 773                 next = (struct fw_cdev_iso_packet __user *)
 774                         &p->header[header_length / 4];
 775                 if (next > end)
 776                         return -EINVAL;
 777                 if (__copy_from_user
 778                     (u.packet.header, p->header, header_length))
 779                         return -EFAULT;
 780                 if (u.packet.skip && ctx->type == FW_ISO_CONTEXT_TRANSMIT &&
 781                     u.packet.header_length + u.packet.payload_length > 0)
 782                         return -EINVAL;
 783                 if (payload + u.packet.payload_length > buffer_end)
 784                         return -EINVAL;
 785
 786                 if (fw_iso_context_queue(ctx, &u.packet,
 787                                          &client->buffer, payload))
 788                         break;
 789
 790                 p = next;
 791                 payload += u.packet.payload_length;
 792                 count++;
 793         }
 794
 795         request->size    -= uptr_to_u64(p) - request->packets;
 796         request->packets  = uptr_to_u64(p);
 797         request->data     = client->vm_start + payload;
 798
 799         return count;
 800 }
 801
 802 static int ioctl_start_iso(struct client *client, void *buffer)
 803 {
 804         struct fw_cdev_start_iso *request = buffer;
 805
 806         if (client->iso_context == NULL || request->handle != 0)
 807                 return -EINVAL;
 808
 809         if (client->iso_context->type == FW_ISO_CONTEXT_RECEIVE) {
 810                 if (request->tags == 0 || request->tags > 15)
 811                         return -EINVAL;
 812
 813                 if (request->sync > 15)
 814                         return -EINVAL;
 815         }
 816
 817         return fw_iso_context_start(client->iso_context, request->cycle,
 818                                     request->sync, request->tags);
 819 }
 820
 821 static int ioctl_stop_iso(struct client *client, void *buffer)
 822 {
 823         struct fw_cdev_stop_iso *request = buffer;
 824
 825         if (client->iso_context == NULL || request->handle != 0)
 826                 return -EINVAL;
 827
 828         return fw_iso_context_stop(client->iso_context);
 829 }
 830
 831 static int ioctl_get_cycle_timer(struct client *client, void *buffer)
 832 {
 833         struct fw_cdev_get_cycle_timer *request = buffer;
 834         struct fw_card *card = client->device->card;
 835         unsigned long long bus_time;
 836         struct timeval tv;
 837         unsigned long flags;
 838
 839         preempt_disable();
 840         local_irq_save(flags);
 841
 842         bus_time = card->driver->get_bus_time(card);
 843         do_gettimeofday(&tv);
 844
 845         local_irq_restore(flags);
 846         preempt_enable();
 847
 848         request->local_time = tv.tv_sec * 1000000ULL + tv.tv_usec;
 849         request->cycle_timer = bus_time & 0xffffffff;
 850         return 0;
 851 }
 852
 853 static int (* const ioctl_handlers[])(struct client *client, void *buffer) = {
 854         ioctl_get_info,
 855         ioctl_send_request,
 856         ioctl_allocate,
 857         ioctl_deallocate,
 858         ioctl_send_response,
 859         ioctl_initiate_bus_reset,
 860         ioctl_add_descriptor,
 861         ioctl_remove_descriptor,
 862         ioctl_create_iso_context,
 863         ioctl_queue_iso,
 864         ioctl_start_iso,
 865         ioctl_stop_iso,
 866         ioctl_get_cycle_timer,
 867 };
 868
 869 static int
 870 dispatch_ioctl(struct client *client, unsigned int cmd, void __user *arg)
 871 {
 872         char buffer[256];
 873         int retval;
 874
 875         if (_IOC_TYPE(cmd) != '#' ||
 876             _IOC_NR(cmd) >= ARRAY_SIZE(ioctl_handlers))
 877                 return -EINVAL;
 878
 879         if (_IOC_DIR(cmd) & _IOC_WRITE) {
 880                 if (_IOC_SIZE(cmd) > sizeof(buffer) ||
 881                     copy_from_user(buffer, arg, _IOC_SIZE(cmd)))
 882                         return -EFAULT;
 883         }
 884
 885         retval = ioctl_handlers[_IOC_NR(cmd)](client, buffer);
 886         if (retval < 0)
 887                 return retval;
 888
 889         if (_IOC_DIR(cmd) & _IOC_READ) {
 890                 if (_IOC_SIZE(cmd) > sizeof(buffer) ||
 891                     copy_to_user(arg, buffer, _IOC_SIZE(cmd)))
 892                         return -EFAULT;
 893         }
 894
 895         return 0;
 896 }
 897
 898 static long
 899 fw_device_op_ioctl(struct file *file,
 900                    unsigned int cmd, unsigned long arg)
 901 {
 902         struct client *client = file->private_data;
 903
 904         return dispatch_ioctl(client, cmd, (void __user *) arg);
 905 }
 906
 907 #ifdef CONFIG_COMPAT
 908 static long
 909 fw_device_op_compat_ioctl(struct file *file,
 910                           unsigned int cmd, unsigned long arg)
 911 {
 912         struct client *client = file->private_data;
 913
 914         return dispatch_ioctl(client, cmd, compat_ptr(arg));
 915 }
 916 #endif
 917
 918 static int fw_device_op_mmap(struct file *file, struct vm_area_struct *vma)
 919 {
 920         struct client *client = file->private_data;
 921         enum dma_data_direction direction;
 922         unsigned long size;
 923         int page_count, retval;
 924
 925         /* FIXME: We could support multiple buffers, but we don't. */
 926         if (client->buffer.pages != NULL)
 927                 return -EBUSY;
 928
 929         if (!(vma->vm_flags & VM_SHARED))
 930                 return -EINVAL;
 931
 932         if (vma->vm_start & ~PAGE_MASK)
 933                 return -EINVAL;
 934
 935         client->vm_start = vma->vm_start;
 936         size = vma->vm_end - vma->vm_start;
 937         page_count = size >> PAGE_SHIFT;
 938         if (size & ~PAGE_MASK)
 939                 return -EINVAL;
 940
 941         if (vma->vm_flags & VM_WRITE)
 942                 direction = DMA_TO_DEVICE;
 943         else
 944                 direction = DMA_FROM_DEVICE;
 945
 946         retval = fw_iso_buffer_init(&client->buffer, client->device->card,
 947                                     page_count, direction);
 948         if (retval < 0)
 949                 return retval;
 950
 951         retval = fw_iso_buffer_map(&client->buffer, vma);
 952         if (retval < 0)
 953                 fw_iso_buffer_destroy(&client->buffer, client->device->card);
 954
 955         return retval;
 956 }
 957
 958 static int fw_device_op_release(struct inode *inode, struct file *file)
 959 {
 960         struct client *client = file->private_data;
 961         struct event *e, *next_e;
 962         struct client_resource *r, *next_r;
 963         unsigned long flags;
 964
 965         if (client->buffer.pages)
 966                 fw_iso_buffer_destroy(&client->buffer, client->device->card);
 967
 968         if (client->iso_context)
 969                 fw_iso_context_destroy(client->iso_context);
 970
 971         list_for_each_entry_safe(r, next_r, &client->resource_list, link)
 972                 r->release(client, r);
 973
 974         /*
 975          * FIXME: We should wait for the async tasklets to stop
 976          * running before freeing the memory.
 977          */
 978
 979         list_for_each_entry_safe(e, next_e, &client->event_list, link)
 980                 kfree(e);
 981
 982         spin_lock_irqsave(&client->device->card->lock, flags);
 983         list_del(&client->link);
 984         spin_unlock_irqrestore(&client->device->card->lock, flags);
 985
 986         fw_device_put(client->device);
 987         kfree(client);
 988
 989         return 0;
 990 }
 991
 992 static unsigned int fw_device_op_poll(struct file *file, poll_table * pt)
 993 {
 994         struct client *client = file->private_data;
 995         unsigned int mask = 0;
 996
 997         poll_wait(file, &client->wait, pt);
 998
 999         if (fw_device_is_shutdown(client->device))
1000                 mask |= POLLHUP | POLLERR;
1001         if (!list_empty(&client->event_list))
1002                 mask |= POLLIN | POLLRDNORM;
1003
1004         return mask;
1005 }
1006
1007 const struct file_operations fw_device_ops = {
1008         .owner          = THIS_MODULE,
1009         .open           = fw_device_op_open,
1010         .read           = fw_device_op_read,
1011         .unlocked_ioctl = fw_device_op_ioctl,
1012         .poll           = fw_device_op_poll,
1013         .release        = fw_device_op_release,
1014         .mmap           = fw_device_op_mmap,
1015
1016 #ifdef CONFIG_COMPAT
1017         .compat_ioctl   = fw_device_op_compat_ioctl,
1018 #endif
1019 };