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