drivers/char/agp/frontend.c

   1 /*
   2  * AGPGART driver frontend
   3  * Copyright (C) 2004 Silicon Graphics, Inc.
   4  * Copyright (C) 2002-2003 Dave Jones
   5  * Copyright (C) 1999 Jeff Hartmann
   6  * Copyright (C) 1999 Precision Insight, Inc.
   7  * Copyright (C) 1999 Xi Graphics, Inc.
   8  *
   9  * Permission is hereby granted, free of charge, to any person obtaining a
  10  * copy of this software and associated documentation files (the "Software"),
  11  * to deal in the Software without restriction, including without limitation
  12  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  13  * and/or sell copies of the Software, and to permit persons to whom the
  14  * Software is furnished to do so, subject to the following conditions:
  15  *
  16  * The above copyright notice and this permission notice shall be included
  17  * in all copies or substantial portions of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  20  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  22  * JEFF HARTMANN, OR ANY OTHER CONTRIBUTORS BE LIABLE FOR ANY CLAIM,
  23  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  24  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
  25  * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  26  *
  27  */
  28
  29 #include <linux/types.h>
  30 #include <linux/kernel.h>
  31 #include <linux/module.h>
  32 #include <linux/mman.h>
  33 #include <linux/pci.h>
  34 #include <linux/init.h>
  35 #include <linux/miscdevice.h>
  36 #include <linux/agp_backend.h>
  37 #include <linux/agpgart.h>
  38 #include <linux/slab.h>
  39 #include <linux/mm.h>
  40 #include <asm/uaccess.h>
  41 #include <asm/pgtable.h>
  42 #include "agp.h"
  43
  44 static struct agp_front_data agp_fe;
  45
  46 static struct agp_memory *agp_find_mem_by_key(int key)
  47 {
  48         struct agp_memory *curr;
  49
  50         if (agp_fe.current_controller == NULL)
  51                 return NULL;
  52
  53         curr = agp_fe.current_controller->pool;
  54
  55         while (curr != NULL) {
  56                 if (curr->key == key)
  57                         break;
  58                 curr = curr->next;
  59         }
  60
  61         DBG("key=%d -> mem=%p", key, curr);
  62         return curr;
  63 }
  64
  65 static void agp_remove_from_pool(struct agp_memory *temp)
  66 {
  67         struct agp_memory *prev;
  68         struct agp_memory *next;
  69
  70         /* Check to see if this is even in the memory pool */
  71
  72         DBG("mem=%p", temp);
  73         if (agp_find_mem_by_key(temp->key) != NULL) {
  74                 next = temp->next;
  75                 prev = temp->prev;
  76
  77                 if (prev != NULL) {
  78                         prev->next = next;
  79                         if (next != NULL)
  80                                 next->prev = prev;
  81
  82                 } else {
  83                         /* This is the first item on the list */
  84                         if (next != NULL)
  85                                 next->prev = NULL;
  86
  87                         agp_fe.current_controller->pool = next;
  88                 }
  89         }
  90 }
  91
  92 /*
  93  * Routines for managing each client's segment list -
  94  * These routines handle adding and removing segments
  95  * to each auth'ed client.
  96  */
  97
  98 static struct
  99 agp_segment_priv *agp_find_seg_in_client(const struct agp_client *client,
 100                                                 unsigned long offset,
 101                                             int size, pgprot_t page_prot)
 102 {
 103         struct agp_segment_priv *seg;
 104         int num_segments, i;
 105         off_t pg_start;
 106         size_t pg_count;
 107
 108         pg_start = offset / 4096;
 109         pg_count = size / 4096;
 110         seg = *(client->segments);
 111         num_segments = client->num_segments;
 112
 113         for (i = 0; i < client->num_segments; i++) {
 114                 if ((seg[i].pg_start == pg_start) &&
 115                     (seg[i].pg_count == pg_count) &&
 116                     (pgprot_val(seg[i].prot) == pgprot_val(page_prot))) {
 117                         return seg + i;
 118                 }
 119         }
 120
 121         return NULL;
 122 }
 123
 124 static void agp_remove_seg_from_client(struct agp_client *client)
 125 {
 126         DBG("client=%p", client);
 127
 128         if (client->segments != NULL) {
 129                 if (*(client->segments) != NULL) {
 130                         DBG("Freeing %p from client %p", *(client->segments), client);
 131                         kfree(*(client->segments));
 132                 }
 133                 DBG("Freeing %p from client %p", client->segments, client);
 134                 kfree(client->segments);
 135                 client->segments = NULL;
 136         }
 137 }
 138
 139 static void agp_add_seg_to_client(struct agp_client *client,
 140                                struct agp_segment_priv ** seg, int num_segments)
 141 {
 142         struct agp_segment_priv **prev_seg;
 143
 144         prev_seg = client->segments;
 145
 146         if (prev_seg != NULL)
 147                 agp_remove_seg_from_client(client);
 148
 149         DBG("Adding seg %p (%d segments) to client %p", seg, num_segments, client);
 150         client->num_segments = num_segments;
 151         client->segments = seg;
 152 }
 153
 154 /* Originally taken from linux/mm/mmap.c from the array
 155  * protection_map.
 156  * The original really should be exported to modules, or
 157  * some routine which does the conversion for you
 158  */
 159
 160 static const pgprot_t my_protect_map[16] =
 161 {
 162         __P000, __P001, __P010, __P011, __P100, __P101, __P110, __P111,
 163         __S000, __S001, __S010, __S011, __S100, __S101, __S110, __S111
 164 };
 165
 166 static pgprot_t agp_convert_mmap_flags(int prot)
 167 {
 168 #define _trans(x,bit1,bit2) \
 169 ((bit1==bit2)?(x&bit1):(x&bit1)?bit2:0)
 170
 171         unsigned long prot_bits;
 172         pgprot_t temp;
 173
 174         prot_bits = _trans(prot, PROT_READ, VM_READ) |
 175             _trans(prot, PROT_WRITE, VM_WRITE) |
 176             _trans(prot, PROT_EXEC, VM_EXEC);
 177
 178         prot_bits |= VM_SHARED;
 179
 180         temp = my_protect_map[prot_bits & 0x0000000f];
 181
 182         return temp;
 183 }
 184
 185 static int agp_create_segment(struct agp_client *client, struct agp_region *region)
 186 {
 187         struct agp_segment_priv **ret_seg;
 188         struct agp_segment_priv *seg;
 189         struct agp_segment *user_seg;
 190         size_t i;
 191
 192         seg = kzalloc((sizeof(struct agp_segment_priv) * region->seg_count), GFP_KERNEL);
 193         if (seg == NULL) {
 194                 kfree(region->seg_list);
 195                 region->seg_list = NULL;
 196                 return -ENOMEM;
 197         }
 198         user_seg = region->seg_list;
 199
 200         for (i = 0; i < region->seg_count; i++) {
 201                 seg[i].pg_start = user_seg[i].pg_start;
 202                 seg[i].pg_count = user_seg[i].pg_count;
 203                 seg[i].prot = agp_convert_mmap_flags(user_seg[i].prot);
 204         }
 205         kfree(region->seg_list);
 206         region->seg_list = NULL;
 207
 208         ret_seg = kmalloc(sizeof(void *), GFP_KERNEL);
 209         if (ret_seg == NULL) {
 210                 kfree(seg);
 211                 return -ENOMEM;
 212         }
 213         *ret_seg = seg;
 214         agp_add_seg_to_client(client, ret_seg, region->seg_count);
 215         return 0;
 216 }
 217
 218 /* End - Routines for managing each client's segment list */
 219
 220 /* This function must only be called when current_controller != NULL */
 221 static void agp_insert_into_pool(struct agp_memory * temp)
 222 {
 223         struct agp_memory *prev;
 224
 225         prev = agp_fe.current_controller->pool;
 226
 227         if (prev != NULL) {
 228                 prev->prev = temp;
 229                 temp->next = prev;
 230         }
 231         agp_fe.current_controller->pool = temp;
 232 }
 233
 234
 235 /* File private list routines */
 236
 237 static struct agp_file_private *agp_find_private(pid_t pid)
 238 {
 239         struct agp_file_private *curr;
 240
 241         curr = agp_fe.file_priv_list;
 242
 243         while (curr != NULL) {
 244                 if (curr->my_pid == pid)
 245                         return curr;
 246                 curr = curr->next;
 247         }
 248
 249         return NULL;
 250 }
 251
 252 static void agp_insert_file_private(struct agp_file_private * priv)
 253 {
 254         struct agp_file_private *prev;
 255
 256         prev = agp_fe.file_priv_list;
 257
 258         if (prev != NULL)
 259                 prev->prev = priv;
 260         priv->next = prev;
 261         agp_fe.file_priv_list = priv;
 262 }
 263
 264 static void agp_remove_file_private(struct agp_file_private * priv)
 265 {
 266         struct agp_file_private *next;
 267         struct agp_file_private *prev;
 268
 269         next = priv->next;
 270         prev = priv->prev;
 271
 272         if (prev != NULL) {
 273                 prev->next = next;
 274
 275                 if (next != NULL)
 276                         next->prev = prev;
 277
 278         } else {
 279                 if (next != NULL)
 280                         next->prev = NULL;
 281
 282                 agp_fe.file_priv_list = next;
 283         }
 284 }
 285
 286 /* End - File flag list routines */
 287
 288 /*
 289  * Wrappers for agp_free_memory & agp_allocate_memory
 290  * These make sure that internal lists are kept updated.
 291  */
 292 static void agp_free_memory_wrap(struct agp_memory *memory)
 293 {
 294         agp_remove_from_pool(memory);
 295         agp_free_memory(memory);
 296 }
 297
 298 static struct agp_memory *agp_allocate_memory_wrap(size_t pg_count, u32 type)
 299 {
 300         struct agp_memory *memory;
 301
 302         memory = agp_allocate_memory(agp_bridge, pg_count, type);
 303         if (memory == NULL)
 304                 return NULL;
 305
 306         agp_insert_into_pool(memory);
 307         return memory;
 308 }
 309
 310 /* Routines for managing the list of controllers -
 311  * These routines manage the current controller, and the list of
 312  * controllers
 313  */
 314
 315 static struct agp_controller *agp_find_controller_by_pid(pid_t id)
 316 {
 317         struct agp_controller *controller;
 318
 319         controller = agp_fe.controllers;
 320
 321         while (controller != NULL) {
 322                 if (controller->pid == id)
 323                         return controller;
 324                 controller = controller->next;
 325         }
 326
 327         return NULL;
 328 }
 329
 330 static struct agp_controller *agp_create_controller(pid_t id)
 331 {
 332         struct agp_controller *controller;
 333
 334         controller = kzalloc(sizeof(struct agp_controller), GFP_KERNEL);
 335         if (controller == NULL)
 336                 return NULL;
 337
 338         controller->pid = id;
 339         return controller;
 340 }
 341
 342 static int agp_insert_controller(struct agp_controller *controller)
 343 {
 344         struct agp_controller *prev_controller;
 345
 346         prev_controller = agp_fe.controllers;
 347         controller->next = prev_controller;
 348
 349         if (prev_controller != NULL)
 350                 prev_controller->prev = controller;
 351
 352         agp_fe.controllers = controller;
 353
 354         return 0;
 355 }
 356
 357 static void agp_remove_all_clients(struct agp_controller *controller)
 358 {
 359         struct agp_client *client;
 360         struct agp_client *temp;
 361
 362         client = controller->clients;
 363
 364         while (client) {
 365                 struct agp_file_private *priv;
 366
 367                 temp = client;
 368                 agp_remove_seg_from_client(temp);
 369                 priv = agp_find_private(temp->pid);
 370
 371                 if (priv != NULL) {
 372                         clear_bit(AGP_FF_IS_VALID, &priv->access_flags);
 373                         clear_bit(AGP_FF_IS_CLIENT, &priv->access_flags);
 374                 }
 375                 client = client->next;
 376                 kfree(temp);
 377         }
 378 }
 379
 380 static void agp_remove_all_memory(struct agp_controller *controller)
 381 {
 382         struct agp_memory *memory;
 383         struct agp_memory *temp;
 384
 385         memory = controller->pool;
 386
 387         while (memory) {
 388                 temp = memory;
 389                 memory = memory->next;
 390                 agp_free_memory_wrap(temp);
 391         }
 392 }
 393
 394 static int agp_remove_controller(struct agp_controller *controller)
 395 {
 396         struct agp_controller *prev_controller;
 397         struct agp_controller *next_controller;
 398
 399         prev_controller = controller->prev;
 400         next_controller = controller->next;
 401
 402         if (prev_controller != NULL) {
 403                 prev_controller->next = next_controller;
 404                 if (next_controller != NULL)
 405                         next_controller->prev = prev_controller;
 406
 407         } else {
 408                 if (next_controller != NULL)
 409                         next_controller->prev = NULL;
 410
 411                 agp_fe.controllers = next_controller;
 412         }
 413
 414         agp_remove_all_memory(controller);
 415         agp_remove_all_clients(controller);
 416
 417         if (agp_fe.current_controller == controller) {
 418                 agp_fe.current_controller = NULL;
 419                 agp_fe.backend_acquired = FALSE;
 420                 agp_backend_release(agp_bridge);
 421         }
 422         kfree(controller);
 423         return 0;
 424 }
 425
 426 static void agp_controller_make_current(struct agp_controller *controller)
 427 {
 428         struct agp_client *clients;
 429
 430         clients = controller->clients;
 431
 432         while (clients != NULL) {
 433                 struct agp_file_private *priv;
 434
 435                 priv = agp_find_private(clients->pid);
 436
 437                 if (priv != NULL) {
 438                         set_bit(AGP_FF_IS_VALID, &priv->access_flags);
 439                         set_bit(AGP_FF_IS_CLIENT, &priv->access_flags);
 440                 }
 441                 clients = clients->next;
 442         }
 443
 444         agp_fe.current_controller = controller;
 445 }
 446
 447 static void agp_controller_release_current(struct agp_controller *controller,
 448                                       struct agp_file_private *controller_priv)
 449 {
 450         struct agp_client *clients;
 451
 452         clear_bit(AGP_FF_IS_VALID, &controller_priv->access_flags);
 453         clients = controller->clients;
 454
 455         while (clients != NULL) {
 456                 struct agp_file_private *priv;
 457
 458                 priv = agp_find_private(clients->pid);
 459
 460                 if (priv != NULL)
 461                         clear_bit(AGP_FF_IS_VALID, &priv->access_flags);
 462
 463                 clients = clients->next;
 464         }
 465
 466         agp_fe.current_controller = NULL;
 467         agp_fe.used_by_controller = FALSE;
 468         agp_backend_release(agp_bridge);
 469 }
 470
 471 /*
 472  * Routines for managing client lists -
 473  * These routines are for managing the list of auth'ed clients.
 474  */
 475
 476 static struct agp_client
 477 *agp_find_client_in_controller(struct agp_controller *controller, pid_t id)
 478 {
 479         struct agp_client *client;
 480
 481         if (controller == NULL)
 482                 return NULL;
 483
 484         client = controller->clients;
 485
 486         while (client != NULL) {
 487                 if (client->pid == id)
 488                         return client;
 489                 client = client->next;
 490         }
 491
 492         return NULL;
 493 }
 494
 495 static struct agp_controller *agp_find_controller_for_client(pid_t id)
 496 {
 497         struct agp_controller *controller;
 498
 499         controller = agp_fe.controllers;
 500
 501         while (controller != NULL) {
 502                 if ((agp_find_client_in_controller(controller, id)) != NULL)
 503                         return controller;
 504                 controller = controller->next;
 505         }
 506
 507         return NULL;
 508 }
 509
 510 static struct agp_client *agp_find_client_by_pid(pid_t id)
 511 {
 512         struct agp_client *temp;
 513
 514         if (agp_fe.current_controller == NULL)
 515                 return NULL;
 516
 517         temp = agp_find_client_in_controller(agp_fe.current_controller, id);
 518         return temp;
 519 }
 520
 521 static void agp_insert_client(struct agp_client *client)
 522 {
 523         struct agp_client *prev_client;
 524
 525         prev_client = agp_fe.current_controller->clients;
 526         client->next = prev_client;
 527
 528         if (prev_client != NULL)
 529                 prev_client->prev = client;
 530
 531         agp_fe.current_controller->clients = client;
 532         agp_fe.current_controller->num_clients++;
 533 }
 534
 535 static struct agp_client *agp_create_client(pid_t id)
 536 {
 537         struct agp_client *new_client;
 538
 539         new_client = kzalloc(sizeof(struct agp_client), GFP_KERNEL);
 540         if (new_client == NULL)
 541                 return NULL;
 542
 543         new_client->pid = id;
 544         agp_insert_client(new_client);
 545         return new_client;
 546 }
 547
 548 static int agp_remove_client(pid_t id)
 549 {
 550         struct agp_client *client;
 551         struct agp_client *prev_client;
 552         struct agp_client *next_client;
 553         struct agp_controller *controller;
 554
 555         controller = agp_find_controller_for_client(id);
 556         if (controller == NULL)
 557                 return -EINVAL;
 558
 559         client = agp_find_client_in_controller(controller, id);
 560         if (client == NULL)
 561                 return -EINVAL;
 562
 563         prev_client = client->prev;
 564         next_client = client->next;
 565
 566         if (prev_client != NULL) {
 567                 prev_client->next = next_client;
 568                 if (next_client != NULL)
 569                         next_client->prev = prev_client;
 570
 571         } else {
 572                 if (next_client != NULL)
 573                         next_client->prev = NULL;
 574                 controller->clients = next_client;
 575         }
 576
 577         controller->num_clients--;
 578         agp_remove_seg_from_client(client);
 579         kfree(client);
 580         return 0;
 581 }
 582
 583 /* End - Routines for managing client lists */
 584
 585 /* File Operations */
 586
 587 static int agp_mmap(struct file *file, struct vm_area_struct *vma)
 588 {
 589         unsigned int size, current_size;
 590         unsigned long offset;
 591         struct agp_client *client;
 592         struct agp_file_private *priv = file->private_data;
 593         struct agp_kern_info kerninfo;
 594
 595         down(&(agp_fe.agp_mutex));
 596
 597         if (agp_fe.backend_acquired != TRUE)
 598                 goto out_eperm;
 599
 600         if (!(test_bit(AGP_FF_IS_VALID, &priv->access_flags)))
 601                 goto out_eperm;
 602
 603         agp_copy_info(agp_bridge, &kerninfo);
 604         size = vma->vm_end - vma->vm_start;
 605         current_size = kerninfo.aper_size;
 606         current_size = current_size * 0x100000;
 607         offset = vma->vm_pgoff << PAGE_SHIFT;
 608         DBG("%lx:%lx", offset, offset+size);
 609
 610         if (test_bit(AGP_FF_IS_CLIENT, &priv->access_flags)) {
 611                 if ((size + offset) > current_size)
 612                         goto out_inval;
 613
 614                 client = agp_find_client_by_pid(current->pid);
 615
 616                 if (client == NULL)
 617                         goto out_eperm;
 618
 619                 if (!agp_find_seg_in_client(client, offset, size, vma->vm_page_prot))
 620                         goto out_inval;
 621
 622                 DBG("client vm_ops=%p", kerninfo.vm_ops);
 623                 if (kerninfo.vm_ops) {
 624                         vma->vm_ops = kerninfo.vm_ops;
 625                 } else if (io_remap_pfn_range(vma, vma->vm_start,
 626                                 (kerninfo.aper_base + offset) >> PAGE_SHIFT,
 627                                             size, vma->vm_page_prot)) {
 628                         goto out_again;
 629                 }
 630                 up(&(agp_fe.agp_mutex));
 631                 return 0;
 632         }
 633
 634         if (test_bit(AGP_FF_IS_CONTROLLER, &priv->access_flags)) {
 635                 if (size != current_size)
 636                         goto out_inval;
 637
 638                 DBG("controller vm_ops=%p", kerninfo.vm_ops);
 639                 if (kerninfo.vm_ops) {
 640                         vma->vm_ops = kerninfo.vm_ops;
 641                 } else if (io_remap_pfn_range(vma, vma->vm_start,
 642                                             kerninfo.aper_base >> PAGE_SHIFT,
 643                                             size, vma->vm_page_prot)) {
 644                         goto out_again;
 645                 }
 646                 up(&(agp_fe.agp_mutex));
 647                 return 0;
 648         }
 649
 650 out_eperm:
 651         up(&(agp_fe.agp_mutex));
 652         return -EPERM;
 653
 654 out_inval:
 655         up(&(agp_fe.agp_mutex));
 656         return -EINVAL;
 657
 658 out_again:
 659         up(&(agp_fe.agp_mutex));
 660         return -EAGAIN;
 661 }
 662
 663 static int agp_release(struct inode *inode, struct file *file)
 664 {
 665         struct agp_file_private *priv = file->private_data;
 666
 667         down(&(agp_fe.agp_mutex));
 668
 669         DBG("priv=%p", priv);
 670
 671         if (test_bit(AGP_FF_IS_CONTROLLER, &priv->access_flags)) {
 672                 struct agp_controller *controller;
 673
 674                 controller = agp_find_controller_by_pid(priv->my_pid);
 675
 676                 if (controller != NULL) {
 677                         if (controller == agp_fe.current_controller)
 678                                 agp_controller_release_current(controller, priv);
 679                         agp_remove_controller(controller);
 680                         controller = NULL;
 681                 }
 682         }
 683
 684         if (test_bit(AGP_FF_IS_CLIENT, &priv->access_flags))
 685                 agp_remove_client(priv->my_pid);
 686
 687         agp_remove_file_private(priv);
 688         kfree(priv);
 689         file->private_data = NULL;
 690         up(&(agp_fe.agp_mutex));
 691         return 0;
 692 }
 693
 694 static int agp_open(struct inode *inode, struct file *file)
 695 {
 696         int minor = iminor(inode);
 697         struct agp_file_private *priv;
 698         struct agp_client *client;
 699         int rc = -ENXIO;
 700
 701         down(&(agp_fe.agp_mutex));
 702
 703         if (minor != AGPGART_MINOR)
 704                 goto err_out;
 705
 706         priv = kzalloc(sizeof(struct agp_file_private), GFP_KERNEL);
 707         if (priv == NULL)
 708                 goto err_out_nomem;
 709
 710         set_bit(AGP_FF_ALLOW_CLIENT, &priv->access_flags);
 711         priv->my_pid = current->pid;
 712
 713         if ((current->uid == 0) || (current->suid == 0)) {
 714                 /* Root priv, can be controller */
 715                 set_bit(AGP_FF_ALLOW_CONTROLLER, &priv->access_flags);
 716         }
 717         client = agp_find_client_by_pid(current->pid);
 718
 719         if (client != NULL) {
 720                 set_bit(AGP_FF_IS_CLIENT, &priv->access_flags);
 721                 set_bit(AGP_FF_IS_VALID, &priv->access_flags);
 722         }
 723         file->private_data = (void *) priv;
 724         agp_insert_file_private(priv);
 725         DBG("private=%p, client=%p", priv, client);
 726         up(&(agp_fe.agp_mutex));
 727         return 0;
 728
 729 err_out_nomem:
 730         rc = -ENOMEM;
 731 err_out:
 732         up(&(agp_fe.agp_mutex));
 733         return rc;
 734 }
 735
 736
 737 static ssize_t agp_read(struct file *file, char __user *buf,
 738                         size_t count, loff_t * ppos)
 739 {
 740         return -EINVAL;
 741 }
 742
 743 static ssize_t agp_write(struct file *file, const char __user *buf,
 744                          size_t count, loff_t * ppos)
 745 {
 746         return -EINVAL;
 747 }
 748
 749 static int agpioc_info_wrap(struct agp_file_private *priv, void __user *arg)
 750 {
 751         struct agp_info userinfo;
 752         struct agp_kern_info kerninfo;
 753
 754         agp_copy_info(agp_bridge, &kerninfo);
 755
 756         userinfo.version.major = kerninfo.version.major;
 757         userinfo.version.minor = kerninfo.version.minor;
 758         userinfo.bridge_id = kerninfo.device->vendor |
 759             (kerninfo.device->device << 16);
 760         userinfo.agp_mode = kerninfo.mode;
 761         userinfo.aper_base = kerninfo.aper_base;
 762         userinfo.aper_size = kerninfo.aper_size;
 763         userinfo.pg_total = userinfo.pg_system = kerninfo.max_memory;
 764         userinfo.pg_used = kerninfo.current_memory;
 765
 766         if (copy_to_user(arg, &userinfo, sizeof(struct agp_info)))
 767                 return -EFAULT;
 768
 769         return 0;
 770 }
 771
 772 static int agpioc_acquire_wrap(struct agp_file_private *priv)
 773 {
 774         struct agp_controller *controller;
 775
 776         DBG("");
 777
 778         if (!(test_bit(AGP_FF_ALLOW_CONTROLLER, &priv->access_flags)))
 779                 return -EPERM;
 780
 781         if (agp_fe.current_controller != NULL)
 782                 return -EBUSY;
 783
 784         if(!agp_bridge)
 785                 return -ENODEV;
 786
 787         if (atomic_read(&agp_bridge->agp_in_use))
 788                 return -EBUSY;
 789
 790         atomic_inc(&agp_bridge->agp_in_use);
 791
 792         agp_fe.backend_acquired = TRUE;
 793
 794         controller = agp_find_controller_by_pid(priv->my_pid);
 795
 796         if (controller != NULL) {
 797                 agp_controller_make_current(controller);
 798         } else {
 799                 controller = agp_create_controller(priv->my_pid);
 800
 801                 if (controller == NULL) {
 802                         agp_fe.backend_acquired = FALSE;
 803                         agp_backend_release(agp_bridge);
 804                         return -ENOMEM;
 805                 }
 806                 agp_insert_controller(controller);
 807                 agp_controller_make_current(controller);
 808         }
 809
 810         set_bit(AGP_FF_IS_CONTROLLER, &priv->access_flags);
 811         set_bit(AGP_FF_IS_VALID, &priv->access_flags);
 812         return 0;
 813 }
 814
 815 static int agpioc_release_wrap(struct agp_file_private *priv)
 816 {
 817         DBG("");
 818         agp_controller_release_current(agp_fe.current_controller, priv);
 819         return 0;
 820 }
 821
 822 static int agpioc_setup_wrap(struct agp_file_private *priv, void __user *arg)
 823 {
 824         struct agp_setup mode;
 825
 826         DBG("");
 827         if (copy_from_user(&mode, arg, sizeof(struct agp_setup)))
 828                 return -EFAULT;
 829
 830         agp_enable(agp_bridge, mode.agp_mode);
 831         return 0;
 832 }
 833
 834 static int agpioc_reserve_wrap(struct agp_file_private *priv, void __user *arg)
 835 {
 836         struct agp_region reserve;
 837         struct agp_client *client;
 838         struct agp_file_private *client_priv;
 839
 840         DBG("");
 841         if (copy_from_user(&reserve, arg, sizeof(struct agp_region)))
 842                 return -EFAULT;
 843
 844         if ((unsigned) reserve.seg_count >= ~0U/sizeof(struct agp_segment))
 845                 return -EFAULT;
 846
 847         client = agp_find_client_by_pid(reserve.pid);
 848
 849         if (reserve.seg_count == 0) {
 850                 /* remove a client */
 851                 client_priv = agp_find_private(reserve.pid);
 852
 853                 if (client_priv != NULL) {
 854                         set_bit(AGP_FF_IS_CLIENT, &client_priv->access_flags);
 855                         set_bit(AGP_FF_IS_VALID, &client_priv->access_flags);
 856                 }
 857                 if (client == NULL) {
 858                         /* client is already removed */
 859                         return 0;
 860                 }
 861                 return agp_remove_client(reserve.pid);
 862         } else {
 863                 struct agp_segment *segment;
 864
 865                 if (reserve.seg_count >= 16384)
 866                         return -EINVAL;
 867
 868                 segment = kmalloc((sizeof(struct agp_segment) * reserve.seg_count),
 869                                   GFP_KERNEL);
 870
 871                 if (segment == NULL)
 872                         return -ENOMEM;
 873
 874                 if (copy_from_user(segment, (void __user *) reserve.seg_list,
 875                                    sizeof(struct agp_segment) * reserve.seg_count)) {
 876                         kfree(segment);
 877                         return -EFAULT;
 878                 }
 879                 reserve.seg_list = segment;
 880
 881                 if (client == NULL) {
 882                         /* Create the client and add the segment */
 883                         client = agp_create_client(reserve.pid);
 884
 885                         if (client == NULL) {
 886                                 kfree(segment);
 887                                 return -ENOMEM;
 888                         }
 889                         client_priv = agp_find_private(reserve.pid);
 890
 891                         if (client_priv != NULL) {
 892                                 set_bit(AGP_FF_IS_CLIENT, &client_priv->access_flags);
 893                                 set_bit(AGP_FF_IS_VALID, &client_priv->access_flags);
 894                         }
 895                 }
 896                 return agp_create_segment(client, &reserve);
 897         }
 898         /* Will never really happen */
 899         return -EINVAL;
 900 }
 901
 902 static int agpioc_protect_wrap(struct agp_file_private *priv)
 903 {
 904         DBG("");
 905         /* This function is not currently implemented */
 906         return -EINVAL;
 907 }
 908
 909 static int agpioc_allocate_wrap(struct agp_file_private *priv, void __user *arg)
 910 {
 911         struct agp_memory *memory;
 912         struct agp_allocate alloc;
 913
 914         DBG("");
 915         if (copy_from_user(&alloc, arg, sizeof(struct agp_allocate)))
 916                 return -EFAULT;
 917
 918         memory = agp_allocate_memory_wrap(alloc.pg_count, alloc.type);
 919
 920         if (memory == NULL)
 921                 return -ENOMEM;
 922
 923         alloc.key = memory->key;
 924         alloc.physical = memory->physical;
 925
 926         if (copy_to_user(arg, &alloc, sizeof(struct agp_allocate))) {
 927                 agp_free_memory_wrap(memory);
 928                 return -EFAULT;
 929         }
 930         return 0;
 931 }
 932
 933 static int agpioc_deallocate_wrap(struct agp_file_private *priv, int arg)
 934 {
 935         struct agp_memory *memory;
 936
 937         DBG("");
 938         memory = agp_find_mem_by_key(arg);
 939
 940         if (memory == NULL)
 941                 return -EINVAL;
 942
 943         agp_free_memory_wrap(memory);
 944         return 0;
 945 }
 946
 947 static int agpioc_bind_wrap(struct agp_file_private *priv, void __user *arg)
 948 {
 949         struct agp_bind bind_info;
 950         struct agp_memory *memory;
 951
 952         DBG("");
 953         if (copy_from_user(&bind_info, arg, sizeof(struct agp_bind)))
 954                 return -EFAULT;
 955
 956         memory = agp_find_mem_by_key(bind_info.key);
 957
 958         if (memory == NULL)
 959                 return -EINVAL;
 960
 961         return agp_bind_memory(memory, bind_info.pg_start);
 962 }
 963
 964 static int agpioc_unbind_wrap(struct agp_file_private *priv, void __user *arg)
 965 {
 966         struct agp_memory *memory;
 967         struct agp_unbind unbind;
 968
 969         DBG("");
 970         if (copy_from_user(&unbind, arg, sizeof(struct agp_unbind)))
 971                 return -EFAULT;
 972
 973         memory = agp_find_mem_by_key(unbind.key);
 974
 975         if (memory == NULL)
 976                 return -EINVAL;
 977
 978         return agp_unbind_memory(memory);
 979 }
 980
 981 static int agp_ioctl(struct inode *inode, struct file *file,
 982                      unsigned int cmd, unsigned long arg)
 983 {
 984         struct agp_file_private *curr_priv = file->private_data;
 985         int ret_val = -ENOTTY;
 986
 987         DBG("priv=%p, cmd=%x", curr_priv, cmd);
 988         down(&(agp_fe.agp_mutex));
 989
 990         if ((agp_fe.current_controller == NULL) &&
 991             (cmd != AGPIOC_ACQUIRE)) {
 992                 ret_val = -EINVAL;
 993                 goto ioctl_out;
 994         }
 995         if ((agp_fe.backend_acquired != TRUE) &&
 996             (cmd != AGPIOC_ACQUIRE)) {
 997                 ret_val = -EBUSY;
 998                 goto ioctl_out;
 999         }
1000         if (cmd != AGPIOC_ACQUIRE) {
1001                 if (!(test_bit(AGP_FF_IS_CONTROLLER, &curr_priv->access_flags))) {
1002                         ret_val = -EPERM;
1003                         goto ioctl_out;
1004                 }
1005                 /* Use the original pid of the controller,
1006                  * in case it's threaded */
1007
1008                 if (agp_fe.current_controller->pid != curr_priv->my_pid) {
1009                         ret_val = -EBUSY;
1010                         goto ioctl_out;
1011                 }
1012         }
1013
1014         switch (cmd) {
1015         case AGPIOC_INFO:
1016                 ret_val = agpioc_info_wrap(curr_priv, (void __user *) arg);
1017                 break;
1018
1019         case AGPIOC_ACQUIRE:
1020                 ret_val = agpioc_acquire_wrap(curr_priv);
1021                 break;
1022
1023         case AGPIOC_RELEASE:
1024                 ret_val = agpioc_release_wrap(curr_priv);
1025                 break;
1026
1027         case AGPIOC_SETUP:
1028                 ret_val = agpioc_setup_wrap(curr_priv, (void __user *) arg);
1029                 break;
1030
1031         case AGPIOC_RESERVE:
1032                 ret_val = agpioc_reserve_wrap(curr_priv, (void __user *) arg);
1033                 break;
1034
1035         case AGPIOC_PROTECT:
1036                 ret_val = agpioc_protect_wrap(curr_priv);
1037                 break;
1038
1039         case AGPIOC_ALLOCATE:
1040                 ret_val = agpioc_allocate_wrap(curr_priv, (void __user *) arg);
1041                 break;
1042
1043         case AGPIOC_DEALLOCATE:
1044                 ret_val = agpioc_deallocate_wrap(curr_priv, (int) arg);
1045                 break;
1046
1047         case AGPIOC_BIND:
1048                 ret_val = agpioc_bind_wrap(curr_priv, (void __user *) arg);
1049                 break;
1050
1051         case AGPIOC_UNBIND:
1052                 ret_val = agpioc_unbind_wrap(curr_priv, (void __user *) arg);
1053                 break;
1054         }
1055
1056 ioctl_out:
1057         DBG("ioctl returns %d\n", ret_val);
1058         up(&(agp_fe.agp_mutex));
1059         return ret_val;
1060 }
1061
1062 static struct file_operations agp_fops =
1063 {
1064         .owner          = THIS_MODULE,
1065         .llseek         = no_llseek,
1066         .read           = agp_read,
1067         .write          = agp_write,
1068         .ioctl          = agp_ioctl,
1069         .mmap           = agp_mmap,
1070         .open           = agp_open,
1071         .release        = agp_release,
1072 };
1073
1074 static struct miscdevice agp_miscdev =
1075 {
1076         .minor  = AGPGART_MINOR,
1077         .name   = "agpgart",
1078         .fops   = &agp_fops
1079 };
1080
1081 int agp_frontend_initialize(void)
1082 {
1083         memset(&agp_fe, 0, sizeof(struct agp_front_data));
1084         sema_init(&(agp_fe.agp_mutex), 1);
1085
1086         if (misc_register(&agp_miscdev)) {
1087                 printk(KERN_ERR PFX "unable to get minor: %d\n", AGPGART_MINOR);
1088                 return -EIO;
1089         }
1090         return 0;
1091 }
1092
1093 void agp_frontend_cleanup(void)
1094 {
1095         misc_deregister(&agp_miscdev);
1096 }