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         if (fw_device_is_shutdown(device)) {
 117                 fw_device_put(device);
 118                 return -ENODEV;
 119         }
 120
 121         client = kzalloc(sizeof(*client), GFP_KERNEL);
 122         if (client == NULL) {
 123                 fw_device_put(device);
 124                 return -ENOMEM;
 125         }
 126
 127         client->device = device;
 128         INIT_LIST_HEAD(&client->event_list);
 129         INIT_LIST_HEAD(&client->resource_list);
 130         spin_lock_init(&client->lock);
 131         init_waitqueue_head(&client->wait);
 132
 133         file->private_data = client;
 134
 135         spin_lock_irqsave(&device->card->lock, flags);
 136         list_add_tail(&client->link, &device->client_list);
 137         spin_unlock_irqrestore(&device->card->lock, flags);
 138
 139         return 0;
 140 }
 141
 142 static void queue_event(struct client *client, struct event *event,
 143                         void *data0, size_t size0, void *data1, size_t size1)
 144 {
 145         unsigned long flags;
 146
 147         event->v[0].data = data0;
 148         event->v[0].size = size0;
 149         event->v[1].data = data1;
 150         event->v[1].size = size1;
 151
 152         spin_lock_irqsave(&client->lock, flags);
 153         list_add_tail(&event->link, &client->event_list);
 154         spin_unlock_irqrestore(&client->lock, flags);
 155
 156         wake_up_interruptible(&client->wait);
 157 }
 158
 159 static int
 160 dequeue_event(struct client *client, char __user *buffer, size_t count)
 161 {
 162         unsigned long flags;
 163         struct event *event;
 164         size_t size, total;
 165         int i, retval;
 166
 167         retval = wait_event_interruptible(client->wait,
 168                                           !list_empty(&client->event_list) ||
 169                                           fw_device_is_shutdown(client->device));
 170         if (retval < 0)
 171                 return retval;
 172
 173         if (list_empty(&client->event_list) &&
 174                        fw_device_is_shutdown(client->device))
 175                 return -ENODEV;
 176
 177         spin_lock_irqsave(&client->lock, flags);
 178         event = container_of(client->event_list.next, struct event, link);
 179         list_del(&event->link);
 180         spin_unlock_irqrestore(&client->lock, flags);
 181
 182         total = 0;
 183         for (i = 0; i < ARRAY_SIZE(event->v) && total < count; i++) {
 184                 size = min(event->v[i].size, count - total);
 185                 if (copy_to_user(buffer + total, event->v[i].data, size)) {
 186                         retval = -EFAULT;
 187                         goto out;
 188                 }
 189                 total += size;
 190         }
 191         retval = total;
 192
 193  out:
 194         kfree(event);
 195
 196         return retval;
 197 }
 198
 199 static ssize_t
 200 fw_device_op_read(struct file *file,
 201                   char __user *buffer, size_t count, loff_t *offset)
 202 {
 203         struct client *client = file->private_data;
 204
 205         return dequeue_event(client, buffer, count);
 206 }
 207
 208 /* caller must hold card->lock so that node pointers can be dereferenced here */
 209 static void
 210 fill_bus_reset_event(struct fw_cdev_event_bus_reset *event,
 211                      struct client *client)
 212 {
 213         struct fw_card *card = client->device->card;
 214
 215         event->closure       = client->bus_reset_closure;
 216         event->type          = FW_CDEV_EVENT_BUS_RESET;
 217         event->generation    = client->device->generation;
 218         event->node_id       = client->device->node_id;
 219         event->local_node_id = card->local_node->node_id;
 220         event->bm_node_id    = 0; /* FIXME: We don't track the BM. */
 221         event->irm_node_id   = card->irm_node->node_id;
 222         event->root_node_id  = card->root_node->node_id;
 223 }
 224
 225 static void
 226 for_each_client(struct fw_device *device,
 227                 void (*callback)(struct client *client))
 228 {
 229         struct fw_card *card = device->card;
 230         struct client *c;
 231         unsigned long flags;
 232
 233         spin_lock_irqsave(&card->lock, flags);
 234
 235         list_for_each_entry(c, &device->client_list, link)
 236                 callback(c);
 237
 238         spin_unlock_irqrestore(&card->lock, flags);
 239 }
 240
 241 static void
 242 queue_bus_reset_event(struct client *client)
 243 {
 244         struct bus_reset *bus_reset;
 245
 246         bus_reset = kzalloc(sizeof(*bus_reset), GFP_ATOMIC);
 247         if (bus_reset == NULL) {
 248                 fw_notify("Out of memory when allocating bus reset event\n");
 249                 return;
 250         }
 251
 252         fill_bus_reset_event(&bus_reset->reset, client);
 253
 254         queue_event(client, &bus_reset->event,
 255                     &bus_reset->reset, sizeof(bus_reset->reset), NULL, 0);
 256 }
 257
 258 void fw_device_cdev_update(struct fw_device *device)
 259 {
 260         for_each_client(device, queue_bus_reset_event);
 261 }
 262
 263 static void wake_up_client(struct client *client)
 264 {
 265         wake_up_interruptible(&client->wait);
 266 }
 267
 268 void fw_device_cdev_remove(struct fw_device *device)
 269 {
 270         for_each_client(device, wake_up_client);
 271 }
 272
 273 static int ioctl_get_info(struct client *client, void *buffer)
 274 {
 275         struct fw_cdev_get_info *get_info = buffer;
 276         struct fw_cdev_event_bus_reset bus_reset;
 277         struct fw_card *card = client->device->card;
 278         unsigned long ret = 0;
 279
 280         client->version = get_info->version;
 281         get_info->version = FW_CDEV_VERSION;
 282
 283         down_read(&fw_device_rwsem);
 284
 285         if (get_info->rom != 0) {
 286                 void __user *uptr = u64_to_uptr(get_info->rom);
 287                 size_t want = get_info->rom_length;
 288                 size_t have = client->device->config_rom_length * 4;
 289
 290                 ret = copy_to_user(uptr, client->device->config_rom,
 291                                    min(want, have));
 292         }
 293         get_info->rom_length = client->device->config_rom_length * 4;
 294
 295         up_read(&fw_device_rwsem);
 296
 297         if (ret != 0)
 298                 return -EFAULT;
 299
 300         client->bus_reset_closure = get_info->bus_reset_closure;
 301         if (get_info->bus_reset != 0) {
 302                 void __user *uptr = u64_to_uptr(get_info->bus_reset);
 303                 unsigned long flags;
 304
 305                 spin_lock_irqsave(&card->lock, flags);
 306                 fill_bus_reset_event(&bus_reset, client);
 307                 spin_unlock_irqrestore(&card->lock, flags);
 308
 309                 if (copy_to_user(uptr, &bus_reset, sizeof(bus_reset)))
 310                         return -EFAULT;
 311         }
 312
 313         get_info->card = card->index;
 314
 315         return 0;
 316 }
 317
 318 static void
 319 add_client_resource(struct client *client, struct client_resource *resource)
 320 {
 321         unsigned long flags;
 322
 323         spin_lock_irqsave(&client->lock, flags);
 324         list_add_tail(&resource->link, &client->resource_list);
 325         resource->handle = client->resource_handle++;
 326         spin_unlock_irqrestore(&client->lock, flags);
 327 }
 328
 329 static int
 330 release_client_resource(struct client *client, u32 handle,
 331                         struct client_resource **resource)
 332 {
 333         struct client_resource *r;
 334         unsigned long flags;
 335
 336         spin_lock_irqsave(&client->lock, flags);
 337         list_for_each_entry(r, &client->resource_list, link) {
 338                 if (r->handle == handle) {
 339                         list_del(&r->link);
 340                         break;
 341                 }
 342         }
 343         spin_unlock_irqrestore(&client->lock, flags);
 344
 345         if (&r->link == &client->resource_list)
 346                 return -EINVAL;
 347
 348         if (resource)
 349                 *resource = r;
 350         else
 351                 r->release(client, r);
 352
 353         return 0;
 354 }
 355
 356 static void
 357 release_transaction(struct client *client, struct client_resource *resource)
 358 {
 359         struct response *response =
 360                 container_of(resource, struct response, resource);
 361
 362         fw_cancel_transaction(client->device->card, &response->transaction);
 363 }
 364
 365 static void
 366 complete_transaction(struct fw_card *card, int rcode,
 367                      void *payload, size_t length, void *data)
 368 {
 369         struct response *response = data;
 370         struct client *client = response->client;
 371         unsigned long flags;
 372
 373         if (length < response->response.length)
 374                 response->response.length = length;
 375         if (rcode == RCODE_COMPLETE)
 376                 memcpy(response->response.data, payload,
 377                        response->response.length);
 378
 379         spin_lock_irqsave(&client->lock, flags);
 380         list_del(&response->resource.link);
 381         spin_unlock_irqrestore(&client->lock, flags);
 382
 383         response->response.type   = FW_CDEV_EVENT_RESPONSE;
 384         response->response.rcode  = rcode;
 385         queue_event(client, &response->event, &response->response,
 386                     sizeof(response->response) + response->response.length,
 387                     NULL, 0);
 388 }
 389
 390 static int ioctl_send_request(struct client *client, void *buffer)
 391 {
 392         struct fw_device *device = client->device;
 393         struct fw_cdev_send_request *request = buffer;
 394         struct response *response;
 395
 396         /* What is the biggest size we'll accept, really? */
 397         if (request->length > 4096)
 398                 return -EINVAL;
 399
 400         response = kmalloc(sizeof(*response) + request->length, GFP_KERNEL);
 401         if (response == NULL)
 402                 return -ENOMEM;
 403
 404         response->client = client;
 405         response->response.length = request->length;
 406         response->response.closure = request->closure;
 407
 408         if (request->data &&
 409             copy_from_user(response->response.data,
 410                            u64_to_uptr(request->data), request->length)) {
 411                 kfree(response);
 412                 return -EFAULT;
 413         }
 414
 415         response->resource.release = release_transaction;
 416         add_client_resource(client, &response->resource);
 417
 418         fw_send_request(device->card, &response->transaction,
 419                         request->tcode & 0x1f,
 420                         device->node->node_id,
 421                         request->generation,
 422                         device->max_speed,
 423                         request->offset,
 424                         response->response.data, request->length,
 425                         complete_transaction, response);
 426
 427         if (request->data)
 428                 return sizeof(request) + request->length;
 429         else
 430                 return sizeof(request);
 431 }
 432
 433 struct address_handler {
 434         struct fw_address_handler handler;
 435         __u64 closure;
 436         struct client *client;
 437         struct client_resource resource;
 438 };
 439
 440 struct request {
 441         struct fw_request *request;
 442         void *data;
 443         size_t length;
 444         struct client_resource resource;
 445 };
 446
 447 struct request_event {
 448         struct event event;
 449         struct fw_cdev_event_request request;
 450 };
 451
 452 static void
 453 release_request(struct client *client, struct client_resource *resource)
 454 {
 455         struct request *request =
 456                 container_of(resource, struct request, resource);
 457
 458         fw_send_response(client->device->card, request->request,
 459                          RCODE_CONFLICT_ERROR);
 460         kfree(request);
 461 }
 462
 463 static void
 464 handle_request(struct fw_card *card, struct fw_request *r,
 465                int tcode, int destination, int source,
 466                int generation, int speed,
 467                unsigned long long offset,
 468                void *payload, size_t length, void *callback_data)
 469 {
 470         struct address_handler *handler = callback_data;
 471         struct request *request;
 472         struct request_event *e;
 473         struct client *client = handler->client;
 474
 475         request = kmalloc(sizeof(*request), GFP_ATOMIC);
 476         e = kmalloc(sizeof(*e), GFP_ATOMIC);
 477         if (request == NULL || e == NULL) {
 478                 kfree(request);
 479                 kfree(e);
 480                 fw_send_response(card, r, RCODE_CONFLICT_ERROR);
 481                 return;
 482         }
 483
 484         request->request = r;
 485         request->data    = payload;
 486         request->length  = length;
 487
 488         request->resource.release = release_request;
 489         add_client_resource(client, &request->resource);
 490
 491         e->request.type    = FW_CDEV_EVENT_REQUEST;
 492         e->request.tcode   = tcode;
 493         e->request.offset  = offset;
 494         e->request.length  = length;
 495         e->request.handle  = request->resource.handle;
 496         e->request.closure = handler->closure;
 497
 498         queue_event(client, &e->event,
 499                     &e->request, sizeof(e->request), payload, length);
 500 }
 501
 502 static void
 503 release_address_handler(struct client *client,
 504                         struct client_resource *resource)
 505 {
 506         struct address_handler *handler =
 507                 container_of(resource, struct address_handler, resource);
 508
 509         fw_core_remove_address_handler(&handler->handler);
 510         kfree(handler);
 511 }
 512
 513 static int ioctl_allocate(struct client *client, void *buffer)
 514 {
 515         struct fw_cdev_allocate *request = buffer;
 516         struct address_handler *handler;
 517         struct fw_address_region region;
 518
 519         handler = kmalloc(sizeof(*handler), GFP_KERNEL);
 520         if (handler == NULL)
 521                 return -ENOMEM;
 522
 523         region.start = request->offset;
 524         region.end = request->offset + request->length;
 525         handler->handler.length = request->length;
 526         handler->handler.address_callback = handle_request;
 527         handler->handler.callback_data = handler;
 528         handler->closure = request->closure;
 529         handler->client = client;
 530
 531         if (fw_core_add_address_handler(&handler->handler, &region) < 0) {
 532                 kfree(handler);
 533                 return -EBUSY;
 534         }
 535
 536         handler->resource.release = release_address_handler;
 537         add_client_resource(client, &handler->resource);
 538         request->handle = handler->resource.handle;
 539
 540         return 0;
 541 }
 542
 543 static int ioctl_deallocate(struct client *client, void *buffer)
 544 {
 545         struct fw_cdev_deallocate *request = buffer;
 546
 547         return release_client_resource(client, request->handle, NULL);
 548 }
 549
 550 static int ioctl_send_response(struct client *client, void *buffer)
 551 {
 552         struct fw_cdev_send_response *request = buffer;
 553         struct client_resource *resource;
 554         struct request *r;
 555
 556         if (release_client_resource(client, request->handle, &resource) < 0)
 557                 return -EINVAL;
 558         r = container_of(resource, struct request, resource);
 559         if (request->length < r->length)
 560                 r->length = request->length;
 561         if (copy_from_user(r->data, u64_to_uptr(request->data), r->length))
 562                 return -EFAULT;
 563
 564         fw_send_response(client->device->card, r->request, request->rcode);
 565         kfree(r);
 566
 567         return 0;
 568 }
 569
 570 static int ioctl_initiate_bus_reset(struct client *client, void *buffer)
 571 {
 572         struct fw_cdev_initiate_bus_reset *request = buffer;
 573         int short_reset;
 574
 575         short_reset = (request->type == FW_CDEV_SHORT_RESET);
 576
 577         return fw_core_initiate_bus_reset(client->device->card, short_reset);
 578 }
 579
 580 struct descriptor {
 581         struct fw_descriptor d;
 582         struct client_resource resource;
 583         u32 data[0];
 584 };
 585
 586 static void release_descriptor(struct client *client,
 587                                struct client_resource *resource)
 588 {
 589         struct descriptor *descriptor =
 590                 container_of(resource, struct descriptor, resource);
 591
 592         fw_core_remove_descriptor(&descriptor->d);
 593         kfree(descriptor);
 594 }
 595
 596 static int ioctl_add_descriptor(struct client *client, void *buffer)
 597 {
 598         struct fw_cdev_add_descriptor *request = buffer;
 599         struct descriptor *descriptor;
 600         int retval;
 601
 602         if (request->length > 256)
 603                 return -EINVAL;
 604
 605         descriptor =
 606                 kmalloc(sizeof(*descriptor) + request->length * 4, GFP_KERNEL);
 607         if (descriptor == NULL)
 608                 return -ENOMEM;
 609
 610         if (copy_from_user(descriptor->data,
 611                            u64_to_uptr(request->data), request->length * 4)) {
 612                 kfree(descriptor);
 613                 return -EFAULT;
 614         }
 615
 616         descriptor->d.length = request->length;
 617         descriptor->d.immediate = request->immediate;
 618         descriptor->d.key = request->key;
 619         descriptor->d.data = descriptor->data;
 620
 621         retval = fw_core_add_descriptor(&descriptor->d);
 622         if (retval < 0) {
 623                 kfree(descriptor);
 624                 return retval;
 625         }
 626
 627         descriptor->resource.release = release_descriptor;
 628         add_client_resource(client, &descriptor->resource);
 629         request->handle = descriptor->resource.handle;
 630
 631         return 0;
 632 }
 633
 634 static int ioctl_remove_descriptor(struct client *client, void *buffer)
 635 {
 636         struct fw_cdev_remove_descriptor *request = buffer;
 637
 638         return release_client_resource(client, request->handle, NULL);
 639 }
 640
 641 static void
 642 iso_callback(struct fw_iso_context *context, u32 cycle,
 643              size_t header_length, void *header, void *data)
 644 {
 645         struct client *client = data;
 646         struct iso_interrupt *irq;
 647
 648         irq = kzalloc(sizeof(*irq) + header_length, GFP_ATOMIC);
 649         if (irq == NULL)
 650                 return;
 651
 652         irq->interrupt.type      = FW_CDEV_EVENT_ISO_INTERRUPT;
 653         irq->interrupt.closure   = client->iso_closure;
 654         irq->interrupt.cycle     = cycle;
 655         irq->interrupt.header_length = header_length;
 656         memcpy(irq->interrupt.header, header, header_length);
 657         queue_event(client, &irq->event, &irq->interrupt,
 658                     sizeof(irq->interrupt) + header_length, NULL, 0);
 659 }
 660
 661 static int ioctl_create_iso_context(struct client *client, void *buffer)
 662 {
 663         struct fw_cdev_create_iso_context *request = buffer;
 664         struct fw_iso_context *context;
 665
 666         /* We only support one context at this time. */
 667         if (client->iso_context != NULL)
 668                 return -EBUSY;
 669
 670         if (request->channel > 63)
 671                 return -EINVAL;
 672
 673         switch (request->type) {
 674         case FW_ISO_CONTEXT_RECEIVE:
 675                 if (request->header_size < 4 || (request->header_size & 3))
 676                         return -EINVAL;
 677
 678                 break;
 679
 680         case FW_ISO_CONTEXT_TRANSMIT:
 681                 if (request->speed > SCODE_3200)
 682                         return -EINVAL;
 683
 684                 break;
 685
 686         default:
 687                 return -EINVAL;
 688         }
 689
 690         context =  fw_iso_context_create(client->device->card,
 691                                          request->type,
 692                                          request->channel,
 693                                          request->speed,
 694                                          request->header_size,
 695                                          iso_callback, client);
 696         if (IS_ERR(context))
 697                 return PTR_ERR(context);
 698
 699         client->iso_closure = request->closure;
 700         client->iso_context = context;
 701
 702         /* We only support one context at this time. */
 703         request->handle = 0;
 704
 705         return 0;
 706 }
 707
 708 /* Macros for decoding the iso packet control header. */
 709 #define GET_PAYLOAD_LENGTH(v)   ((v) & 0xffff)
 710 #define GET_INTERRUPT(v)        (((v) >> 16) & 0x01)
 711 #define GET_SKIP(v)             (((v) >> 17) & 0x01)
 712 #define GET_TAG(v)              (((v) >> 18) & 0x02)
 713 #define GET_SY(v)               (((v) >> 20) & 0x04)
 714 #define GET_HEADER_LENGTH(v)    (((v) >> 24) & 0xff)
 715
 716 static int ioctl_queue_iso(struct client *client, void *buffer)
 717 {
 718         struct fw_cdev_queue_iso *request = buffer;
 719         struct fw_cdev_iso_packet __user *p, *end, *next;
 720         struct fw_iso_context *ctx = client->iso_context;
 721         unsigned long payload, buffer_end, header_length;
 722         u32 control;
 723         int count;
 724         struct {
 725                 struct fw_iso_packet packet;
 726                 u8 header[256];
 727         } u;
 728
 729         if (ctx == NULL || request->handle != 0)
 730                 return -EINVAL;
 731
 732         /*
 733          * If the user passes a non-NULL data pointer, has mmap()'ed
 734          * the iso buffer, and the pointer points inside the buffer,
 735          * we setup the payload pointers accordingly.  Otherwise we
 736          * set them both to 0, which will still let packets with
 737          * payload_length == 0 through.  In other words, if no packets
 738          * use the indirect payload, the iso buffer need not be mapped
 739          * and the request->data pointer is ignored.
 740          */
 741
 742         payload = (unsigned long)request->data - client->vm_start;
 743         buffer_end = client->buffer.page_count << PAGE_SHIFT;
 744         if (request->data == 0 || client->buffer.pages == NULL ||
 745             payload >= buffer_end) {
 746                 payload = 0;
 747                 buffer_end = 0;
 748         }
 749
 750         p = (struct fw_cdev_iso_packet __user *)u64_to_uptr(request->packets);
 751
 752         if (!access_ok(VERIFY_READ, p, request->size))
 753                 return -EFAULT;
 754
 755         end = (void __user *)p + request->size;
 756         count = 0;
 757         while (p < end) {
 758                 if (get_user(control, &p->control))
 759                         return -EFAULT;
 760                 u.packet.payload_length = GET_PAYLOAD_LENGTH(control);
 761                 u.packet.interrupt = GET_INTERRUPT(control);
 762                 u.packet.skip = GET_SKIP(control);
 763                 u.packet.tag = GET_TAG(control);
 764                 u.packet.sy = GET_SY(control);
 765                 u.packet.header_length = GET_HEADER_LENGTH(control);
 766
 767                 if (ctx->type == FW_ISO_CONTEXT_TRANSMIT) {
 768                         header_length = u.packet.header_length;
 769                 } else {
 770                         /*
 771                          * We require that header_length is a multiple of
 772                          * the fixed header size, ctx->header_size.
 773                          */
 774                         if (ctx->header_size == 0) {
 775                                 if (u.packet.header_length > 0)
 776                                         return -EINVAL;
 777                         } else if (u.packet.header_length % ctx->header_size != 0) {
 778                                 return -EINVAL;
 779                         }
 780                         header_length = 0;
 781                 }
 782
 783                 next = (struct fw_cdev_iso_packet __user *)
 784                         &p->header[header_length / 4];
 785                 if (next > end)
 786                         return -EINVAL;
 787                 if (__copy_from_user
 788                     (u.packet.header, p->header, header_length))
 789                         return -EFAULT;
 790                 if (u.packet.skip && ctx->type == FW_ISO_CONTEXT_TRANSMIT &&
 791                     u.packet.header_length + u.packet.payload_length > 0)
 792                         return -EINVAL;
 793                 if (payload + u.packet.payload_length > buffer_end)
 794                         return -EINVAL;
 795
 796                 if (fw_iso_context_queue(ctx, &u.packet,
 797                                          &client->buffer, payload))
 798                         break;
 799
 800                 p = next;
 801                 payload += u.packet.payload_length;
 802                 count++;
 803         }
 804
 805         request->size    -= uptr_to_u64(p) - request->packets;
 806         request->packets  = uptr_to_u64(p);
 807         request->data     = client->vm_start + payload;
 808
 809         return count;
 810 }
 811
 812 static int ioctl_start_iso(struct client *client, void *buffer)
 813 {
 814         struct fw_cdev_start_iso *request = buffer;
 815
 816         if (client->iso_context == NULL || request->handle != 0)
 817                 return -EINVAL;
 818
 819         if (client->iso_context->type == FW_ISO_CONTEXT_RECEIVE) {
 820                 if (request->tags == 0 || request->tags > 15)
 821                         return -EINVAL;
 822
 823                 if (request->sync > 15)
 824                         return -EINVAL;
 825         }
 826
 827         return fw_iso_context_start(client->iso_context, request->cycle,
 828                                     request->sync, request->tags);
 829 }
 830
 831 static int ioctl_stop_iso(struct client *client, void *buffer)
 832 {
 833         struct fw_cdev_stop_iso *request = buffer;
 834
 835         if (client->iso_context == NULL || request->handle != 0)
 836                 return -EINVAL;
 837
 838         return fw_iso_context_stop(client->iso_context);
 839 }
 840
 841 static int ioctl_get_cycle_timer(struct client *client, void *buffer)
 842 {
 843         struct fw_cdev_get_cycle_timer *request = buffer;
 844         struct fw_card *card = client->device->card;
 845         unsigned long long bus_time;
 846         struct timeval tv;
 847         unsigned long flags;
 848
 849         preempt_disable();
 850         local_irq_save(flags);
 851
 852         bus_time = card->driver->get_bus_time(card);
 853         do_gettimeofday(&tv);
 854
 855         local_irq_restore(flags);
 856         preempt_enable();
 857
 858         request->local_time = tv.tv_sec * 1000000ULL + tv.tv_usec;
 859         request->cycle_timer = bus_time & 0xffffffff;
 860         return 0;
 861 }
 862
 863 static int (* const ioctl_handlers[])(struct client *client, void *buffer) = {
 864         ioctl_get_info,
 865         ioctl_send_request,
 866         ioctl_allocate,
 867         ioctl_deallocate,
 868         ioctl_send_response,
 869         ioctl_initiate_bus_reset,
 870         ioctl_add_descriptor,
 871         ioctl_remove_descriptor,
 872         ioctl_create_iso_context,
 873         ioctl_queue_iso,
 874         ioctl_start_iso,
 875         ioctl_stop_iso,
 876         ioctl_get_cycle_timer,
 877 };
 878
 879 static int
 880 dispatch_ioctl(struct client *client, unsigned int cmd, void __user *arg)
 881 {
 882         char buffer[256];
 883         int retval;
 884
 885         if (_IOC_TYPE(cmd) != '#' ||
 886             _IOC_NR(cmd) >= ARRAY_SIZE(ioctl_handlers))
 887                 return -EINVAL;
 888
 889         if (_IOC_DIR(cmd) & _IOC_WRITE) {
 890                 if (_IOC_SIZE(cmd) > sizeof(buffer) ||
 891                     copy_from_user(buffer, arg, _IOC_SIZE(cmd)))
 892                         return -EFAULT;
 893         }
 894
 895         retval = ioctl_handlers[_IOC_NR(cmd)](client, buffer);
 896         if (retval < 0)
 897                 return retval;
 898
 899         if (_IOC_DIR(cmd) & _IOC_READ) {
 900                 if (_IOC_SIZE(cmd) > sizeof(buffer) ||
 901                     copy_to_user(arg, buffer, _IOC_SIZE(cmd)))
 902                         return -EFAULT;
 903         }
 904
 905         return 0;
 906 }
 907
 908 static long
 909 fw_device_op_ioctl(struct file *file,
 910                    unsigned int cmd, unsigned long arg)
 911 {
 912         struct client *client = file->private_data;
 913
 914         if (fw_device_is_shutdown(client->device))
 915                 return -ENODEV;
 916
 917         return dispatch_ioctl(client, cmd, (void __user *) arg);
 918 }
 919
 920 #ifdef CONFIG_COMPAT
 921 static long
 922 fw_device_op_compat_ioctl(struct file *file,
 923                           unsigned int cmd, unsigned long arg)
 924 {
 925         struct client *client = file->private_data;
 926
 927         if (fw_device_is_shutdown(client->device))
 928                 return -ENODEV;
 929
 930         return dispatch_ioctl(client, cmd, compat_ptr(arg));
 931 }
 932 #endif
 933
 934 static int fw_device_op_mmap(struct file *file, struct vm_area_struct *vma)
 935 {
 936         struct client *client = file->private_data;
 937         enum dma_data_direction direction;
 938         unsigned long size;
 939         int page_count, retval;
 940
 941         if (fw_device_is_shutdown(client->device))
 942                 return -ENODEV;
 943
 944         /* FIXME: We could support multiple buffers, but we don't. */
 945         if (client->buffer.pages != NULL)
 946                 return -EBUSY;
 947
 948         if (!(vma->vm_flags & VM_SHARED))
 949                 return -EINVAL;
 950
 951         if (vma->vm_start & ~PAGE_MASK)
 952                 return -EINVAL;
 953
 954         client->vm_start = vma->vm_start;
 955         size = vma->vm_end - vma->vm_start;
 956         page_count = size >> PAGE_SHIFT;
 957         if (size & ~PAGE_MASK)
 958                 return -EINVAL;
 959
 960         if (vma->vm_flags & VM_WRITE)
 961                 direction = DMA_TO_DEVICE;
 962         else
 963                 direction = DMA_FROM_DEVICE;
 964
 965         retval = fw_iso_buffer_init(&client->buffer, client->device->card,
 966                                     page_count, direction);
 967         if (retval < 0)
 968                 return retval;
 969
 970         retval = fw_iso_buffer_map(&client->buffer, vma);
 971         if (retval < 0)
 972                 fw_iso_buffer_destroy(&client->buffer, client->device->card);
 973
 974         return retval;
 975 }
 976
 977 static int fw_device_op_release(struct inode *inode, struct file *file)
 978 {
 979         struct client *client = file->private_data;
 980         struct event *e, *next_e;
 981         struct client_resource *r, *next_r;
 982         unsigned long flags;
 983
 984         if (client->buffer.pages)
 985                 fw_iso_buffer_destroy(&client->buffer, client->device->card);
 986
 987         if (client->iso_context)
 988                 fw_iso_context_destroy(client->iso_context);
 989
 990         list_for_each_entry_safe(r, next_r, &client->resource_list, link)
 991                 r->release(client, r);
 992
 993         /*
 994          * FIXME: We should wait for the async tasklets to stop
 995          * running before freeing the memory.
 996          */
 997
 998         list_for_each_entry_safe(e, next_e, &client->event_list, link)
 999                 kfree(e);
1000
1001         spin_lock_irqsave(&client->device->card->lock, flags);
1002         list_del(&client->link);
1003         spin_unlock_irqrestore(&client->device->card->lock, flags);
1004
1005         fw_device_put(client->device);
1006         kfree(client);
1007
1008         return 0;
1009 }
1010
1011 static unsigned int fw_device_op_poll(struct file *file, poll_table * pt)
1012 {
1013         struct client *client = file->private_data;
1014         unsigned int mask = 0;
1015
1016         poll_wait(file, &client->wait, pt);
1017
1018         if (fw_device_is_shutdown(client->device))
1019                 mask |= POLLHUP | POLLERR;
1020         if (!list_empty(&client->event_list))
1021                 mask |= POLLIN | POLLRDNORM;
1022
1023         return mask;
1024 }
1025
1026 const struct file_operations fw_device_ops = {
1027         .owner          = THIS_MODULE,
1028         .open           = fw_device_op_open,
1029         .read           = fw_device_op_read,
1030         .unlocked_ioctl = fw_device_op_ioctl,
1031         .poll           = fw_device_op_poll,
1032         .release        = fw_device_op_release,
1033         .mmap           = fw_device_op_mmap,
1034
1035 #ifdef CONFIG_COMPAT
1036         .compat_ioctl   = fw_device_op_compat_ioctl,
1037 #endif
1038 };