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