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