drivers/gpu/drm/radeon/radeon_ttm.c

   1 /*
   2  * Copyright 2009 Jerome Glisse.
   3  * All Rights Reserved.
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the
   7  * "Software"), to deal in the Software without restriction, including
   8  * without limitation the rights to use, copy, modify, merge, publish,
   9  * distribute, sub license, and/or sell copies of the Software, and to
  10  * permit persons to whom the Software is furnished to do so, subject to
  11  * the following conditions:
  12  *
  13  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  14  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  15  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  16  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  17  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  18  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  19  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  20  *
  21  * The above copyright notice and this permission notice (including the
  22  * next paragraph) shall be included in all copies or substantial portions
  23  * of the Software.
  24  *
  25  */
  26 /*
  27  * Authors:
  28  *    Jerome Glisse <glisse@freedesktop.org>
  29  *    Thomas Hellstrom <thomas-at-tungstengraphics-dot-com>
  30  *    Dave Airlie
  31  */
  32 #include <ttm/ttm_bo_api.h>
  33 #include <ttm/ttm_bo_driver.h>
  34 #include <ttm/ttm_placement.h>
  35 #include <ttm/ttm_module.h>
  36 #include <drm/drmP.h>
  37 #include <drm/radeon_drm.h>
  38 #include "radeon_reg.h"
  39 #include "radeon.h"
  40
  41 #define DRM_FILE_PAGE_OFFSET (0x100000000ULL >> PAGE_SHIFT)
  42
  43 static struct radeon_device *radeon_get_rdev(struct ttm_bo_device *bdev)
  44 {
  45         struct radeon_mman *mman;
  46         struct radeon_device *rdev;
  47
  48         mman = container_of(bdev, struct radeon_mman, bdev);
  49         rdev = container_of(mman, struct radeon_device, mman);
  50         return rdev;
  51 }
  52
  53
  54 /*
  55  * Global memory.
  56  */
  57 static int radeon_ttm_mem_global_init(struct ttm_global_reference *ref)
  58 {
  59         return ttm_mem_global_init(ref->object);
  60 }
  61
  62 static void radeon_ttm_mem_global_release(struct ttm_global_reference *ref)
  63 {
  64         ttm_mem_global_release(ref->object);
  65 }
  66
  67 static int radeon_ttm_global_init(struct radeon_device *rdev)
  68 {
  69         struct ttm_global_reference *global_ref;
  70         int r;
  71
  72         rdev->mman.mem_global_referenced = false;
  73         global_ref = &rdev->mman.mem_global_ref;
  74         global_ref->global_type = TTM_GLOBAL_TTM_MEM;
  75         global_ref->size = sizeof(struct ttm_mem_global);
  76         global_ref->init = &radeon_ttm_mem_global_init;
  77         global_ref->release = &radeon_ttm_mem_global_release;
  78         r = ttm_global_item_ref(global_ref);
  79         if (r != 0) {
  80                 DRM_ERROR("Failed referencing a global TTM memory object.\n");
  81                 return r;
  82         }
  83         rdev->mman.mem_global_referenced = true;
  84         return 0;
  85 }
  86
  87 static void radeon_ttm_global_fini(struct radeon_device *rdev)
  88 {
  89         if (rdev->mman.mem_global_referenced) {
  90                 ttm_global_item_unref(&rdev->mman.mem_global_ref);
  91                 rdev->mman.mem_global_referenced = false;
  92         }
  93 }
  94
  95 struct ttm_backend *radeon_ttm_backend_create(struct radeon_device *rdev);
  96
  97 static struct ttm_backend*
  98 radeon_create_ttm_backend_entry(struct ttm_bo_device *bdev)
  99 {
 100         struct radeon_device *rdev;
 101
 102         rdev = radeon_get_rdev(bdev);
 103 #if __OS_HAS_AGP
 104         if (rdev->flags & RADEON_IS_AGP) {
 105                 return ttm_agp_backend_init(bdev, rdev->ddev->agp->bridge);
 106         } else
 107 #endif
 108         {
 109                 return radeon_ttm_backend_create(rdev);
 110         }
 111 }
 112
 113 static int radeon_invalidate_caches(struct ttm_bo_device *bdev, uint32_t flags)
 114 {
 115         return 0;
 116 }
 117
 118 static int radeon_init_mem_type(struct ttm_bo_device *bdev, uint32_t type,
 119                                 struct ttm_mem_type_manager *man)
 120 {
 121         struct radeon_device *rdev;
 122
 123         rdev = radeon_get_rdev(bdev);
 124
 125         switch (type) {
 126         case TTM_PL_SYSTEM:
 127                 /* System memory */
 128                 man->flags = TTM_MEMTYPE_FLAG_MAPPABLE;
 129                 man->available_caching = TTM_PL_MASK_CACHING;
 130                 man->default_caching = TTM_PL_FLAG_CACHED;
 131                 break;
 132         case TTM_PL_TT:
 133                 man->gpu_offset = 0;
 134                 man->available_caching = TTM_PL_MASK_CACHING;
 135                 man->default_caching = TTM_PL_FLAG_CACHED;
 136                 man->flags = TTM_MEMTYPE_FLAG_MAPPABLE | TTM_MEMTYPE_FLAG_CMA;
 137 #if __OS_HAS_AGP
 138                 if (rdev->flags & RADEON_IS_AGP) {
 139                         if (!(drm_core_has_AGP(rdev->ddev) && rdev->ddev->agp)) {
 140                                 DRM_ERROR("AGP is not enabled for memory type %u\n",
 141                                           (unsigned)type);
 142                                 return -EINVAL;
 143                         }
 144                         man->io_offset = rdev->mc.agp_base;
 145                         man->io_size = rdev->mc.gtt_size;
 146                         man->io_addr = NULL;
 147                         if (!rdev->ddev->agp->cant_use_aperture)
 148                                 man->flags = TTM_MEMTYPE_FLAG_NEEDS_IOREMAP |
 149                                              TTM_MEMTYPE_FLAG_MAPPABLE;
 150                         man->available_caching = TTM_PL_FLAG_UNCACHED |
 151                                                  TTM_PL_FLAG_WC;
 152                         man->default_caching = TTM_PL_FLAG_WC;
 153                 } else
 154 #endif
 155                 {
 156                         man->io_offset = 0;
 157                         man->io_size = 0;
 158                         man->io_addr = NULL;
 159                 }
 160                 break;
 161         case TTM_PL_VRAM:
 162                 /* "On-card" video ram */
 163                 man->gpu_offset = 0;
 164                 man->flags = TTM_MEMTYPE_FLAG_FIXED |
 165                              TTM_MEMTYPE_FLAG_NEEDS_IOREMAP |
 166                              TTM_MEMTYPE_FLAG_MAPPABLE;
 167                 man->available_caching = TTM_PL_FLAG_UNCACHED | TTM_PL_FLAG_WC;
 168                 man->default_caching = TTM_PL_FLAG_WC;
 169                 man->io_addr = NULL;
 170                 man->io_offset = rdev->mc.aper_base;
 171                 man->io_size = rdev->mc.aper_size;
 172                 break;
 173         default:
 174                 DRM_ERROR("Unsupported memory type %u\n", (unsigned)type);
 175                 return -EINVAL;
 176         }
 177         return 0;
 178 }
 179
 180 static uint32_t radeon_evict_flags(struct ttm_buffer_object *bo)
 181 {
 182         uint32_t cur_placement = bo->mem.placement & ~TTM_PL_MASK_MEMTYPE;
 183
 184         switch (bo->mem.mem_type) {
 185         default:
 186                 return (cur_placement & ~TTM_PL_MASK_CACHING) |
 187                         TTM_PL_FLAG_SYSTEM |
 188                         TTM_PL_FLAG_CACHED;
 189         }
 190 }
 191
 192 static int radeon_verify_access(struct ttm_buffer_object *bo, struct file *filp)
 193 {
 194         return 0;
 195 }
 196
 197 static void radeon_move_null(struct ttm_buffer_object *bo,
 198                              struct ttm_mem_reg *new_mem)
 199 {
 200         struct ttm_mem_reg *old_mem = &bo->mem;
 201
 202         BUG_ON(old_mem->mm_node != NULL);
 203         *old_mem = *new_mem;
 204         new_mem->mm_node = NULL;
 205 }
 206
 207 static int radeon_move_blit(struct ttm_buffer_object *bo,
 208                             bool evict, int no_wait,
 209                             struct ttm_mem_reg *new_mem,
 210                             struct ttm_mem_reg *old_mem)
 211 {
 212         struct radeon_device *rdev;
 213         uint64_t old_start, new_start;
 214         struct radeon_fence *fence;
 215         int r;
 216
 217         rdev = radeon_get_rdev(bo->bdev);
 218         r = radeon_fence_create(rdev, &fence);
 219         if (unlikely(r)) {
 220                 return r;
 221         }
 222         old_start = old_mem->mm_node->start << PAGE_SHIFT;
 223         new_start = new_mem->mm_node->start << PAGE_SHIFT;
 224
 225         switch (old_mem->mem_type) {
 226         case TTM_PL_VRAM:
 227                 old_start += rdev->mc.vram_location;
 228                 break;
 229         case TTM_PL_TT:
 230                 old_start += rdev->mc.gtt_location;
 231                 break;
 232         default:
 233                 DRM_ERROR("Unknown placement %d\n", old_mem->mem_type);
 234                 return -EINVAL;
 235         }
 236         switch (new_mem->mem_type) {
 237         case TTM_PL_VRAM:
 238                 new_start += rdev->mc.vram_location;
 239                 break;
 240         case TTM_PL_TT:
 241                 new_start += rdev->mc.gtt_location;
 242                 break;
 243         default:
 244                 DRM_ERROR("Unknown placement %d\n", old_mem->mem_type);
 245                 return -EINVAL;
 246         }
 247         if (!rdev->cp.ready) {
 248                 DRM_ERROR("Trying to move memory with CP turned off.\n");
 249                 return -EINVAL;
 250         }
 251         r = radeon_copy(rdev, old_start, new_start, new_mem->num_pages, fence);
 252         /* FIXME: handle copy error */
 253         r = ttm_bo_move_accel_cleanup(bo, (void *)fence, NULL,
 254                                       evict, no_wait, new_mem);
 255         radeon_fence_unref(&fence);
 256         return r;
 257 }
 258
 259 static int radeon_move_vram_ram(struct ttm_buffer_object *bo,
 260                                 bool evict, bool interruptible, bool no_wait,
 261                                 struct ttm_mem_reg *new_mem)
 262 {
 263         struct radeon_device *rdev;
 264         struct ttm_mem_reg *old_mem = &bo->mem;
 265         struct ttm_mem_reg tmp_mem;
 266         uint32_t proposed_placement;
 267         int r;
 268
 269         rdev = radeon_get_rdev(bo->bdev);
 270         tmp_mem = *new_mem;
 271         tmp_mem.mm_node = NULL;
 272         proposed_placement = TTM_PL_FLAG_TT | TTM_PL_MASK_CACHING;
 273         r = ttm_bo_mem_space(bo, proposed_placement, &tmp_mem,
 274                              interruptible, no_wait);
 275         if (unlikely(r)) {
 276                 return r;
 277         }
 278         r = ttm_tt_bind(bo->ttm, &tmp_mem);
 279         if (unlikely(r)) {
 280                 goto out_cleanup;
 281         }
 282         r = radeon_move_blit(bo, true, no_wait, &tmp_mem, old_mem);
 283         if (unlikely(r)) {
 284                 goto out_cleanup;
 285         }
 286         r = ttm_bo_move_ttm(bo, true, no_wait, new_mem);
 287 out_cleanup:
 288         if (tmp_mem.mm_node) {
 289                 spin_lock(&rdev->mman.bdev.lru_lock);
 290                 drm_mm_put_block(tmp_mem.mm_node);
 291                 spin_unlock(&rdev->mman.bdev.lru_lock);
 292                 return r;
 293         }
 294         return r;
 295 }
 296
 297 static int radeon_move_ram_vram(struct ttm_buffer_object *bo,
 298                                 bool evict, bool interruptible, bool no_wait,
 299                                 struct ttm_mem_reg *new_mem)
 300 {
 301         struct radeon_device *rdev;
 302         struct ttm_mem_reg *old_mem = &bo->mem;
 303         struct ttm_mem_reg tmp_mem;
 304         uint32_t proposed_flags;
 305         int r;
 306
 307         rdev = radeon_get_rdev(bo->bdev);
 308         tmp_mem = *new_mem;
 309         tmp_mem.mm_node = NULL;
 310         proposed_flags = TTM_PL_FLAG_TT | TTM_PL_MASK_CACHING;
 311         r = ttm_bo_mem_space(bo, proposed_flags, &tmp_mem,
 312                              interruptible, no_wait);
 313         if (unlikely(r)) {
 314                 return r;
 315         }
 316         r = ttm_bo_move_ttm(bo, true, no_wait, &tmp_mem);
 317         if (unlikely(r)) {
 318                 goto out_cleanup;
 319         }
 320         r = radeon_move_blit(bo, true, no_wait, new_mem, old_mem);
 321         if (unlikely(r)) {
 322                 goto out_cleanup;
 323         }
 324 out_cleanup:
 325         if (tmp_mem.mm_node) {
 326                 spin_lock(&rdev->mman.bdev.lru_lock);
 327                 drm_mm_put_block(tmp_mem.mm_node);
 328                 spin_unlock(&rdev->mman.bdev.lru_lock);
 329                 return r;
 330         }
 331         return r;
 332 }
 333
 334 static int radeon_bo_move(struct ttm_buffer_object *bo,
 335                           bool evict, bool interruptible, bool no_wait,
 336                           struct ttm_mem_reg *new_mem)
 337 {
 338         struct radeon_device *rdev;
 339         struct ttm_mem_reg *old_mem = &bo->mem;
 340         int r;
 341
 342         rdev = radeon_get_rdev(bo->bdev);
 343         if (old_mem->mem_type == TTM_PL_SYSTEM && bo->ttm == NULL) {
 344                 radeon_move_null(bo, new_mem);
 345                 return 0;
 346         }
 347         if ((old_mem->mem_type == TTM_PL_TT &&
 348              new_mem->mem_type == TTM_PL_SYSTEM) ||
 349             (old_mem->mem_type == TTM_PL_SYSTEM &&
 350              new_mem->mem_type == TTM_PL_TT)) {
 351                 /* bind is enought */
 352                 radeon_move_null(bo, new_mem);
 353                 return 0;
 354         }
 355         if (!rdev->cp.ready) {
 356                 /* use memcpy */
 357                 DRM_ERROR("CP is not ready use memcpy.\n");
 358                 return ttm_bo_move_memcpy(bo, evict, no_wait, new_mem);
 359         }
 360
 361         if (old_mem->mem_type == TTM_PL_VRAM &&
 362             new_mem->mem_type == TTM_PL_SYSTEM) {
 363                 return radeon_move_vram_ram(bo, evict, interruptible,
 364                                             no_wait, new_mem);
 365         } else if (old_mem->mem_type == TTM_PL_SYSTEM &&
 366                    new_mem->mem_type == TTM_PL_VRAM) {
 367                 return radeon_move_ram_vram(bo, evict, interruptible,
 368                                             no_wait, new_mem);
 369         } else {
 370                 r = radeon_move_blit(bo, evict, no_wait, new_mem, old_mem);
 371                 if (unlikely(r)) {
 372                         return r;
 373                 }
 374         }
 375         return r;
 376 }
 377
 378 const uint32_t radeon_mem_prios[] = {
 379         TTM_PL_VRAM,
 380         TTM_PL_TT,
 381         TTM_PL_SYSTEM,
 382 };
 383
 384 const uint32_t radeon_busy_prios[] = {
 385         TTM_PL_TT,
 386         TTM_PL_VRAM,
 387         TTM_PL_SYSTEM,
 388 };
 389
 390 static int radeon_sync_obj_wait(void *sync_obj, void *sync_arg,
 391                                 bool lazy, bool interruptible)
 392 {
 393         return radeon_fence_wait((struct radeon_fence *)sync_obj, interruptible);
 394 }
 395
 396 static int radeon_sync_obj_flush(void *sync_obj, void *sync_arg)
 397 {
 398         return 0;
 399 }
 400
 401 static void radeon_sync_obj_unref(void **sync_obj)
 402 {
 403         radeon_fence_unref((struct radeon_fence **)sync_obj);
 404 }
 405
 406 static void *radeon_sync_obj_ref(void *sync_obj)
 407 {
 408         return radeon_fence_ref((struct radeon_fence *)sync_obj);
 409 }
 410
 411 static bool radeon_sync_obj_signaled(void *sync_obj, void *sync_arg)
 412 {
 413         return radeon_fence_signaled((struct radeon_fence *)sync_obj);
 414 }
 415
 416 static struct ttm_bo_driver radeon_bo_driver = {
 417         .mem_type_prio = radeon_mem_prios,
 418         .mem_busy_prio = radeon_busy_prios,
 419         .num_mem_type_prio = ARRAY_SIZE(radeon_mem_prios),
 420         .num_mem_busy_prio = ARRAY_SIZE(radeon_busy_prios),
 421         .create_ttm_backend_entry = &radeon_create_ttm_backend_entry,
 422         .invalidate_caches = &radeon_invalidate_caches,
 423         .init_mem_type = &radeon_init_mem_type,
 424         .evict_flags = &radeon_evict_flags,
 425         .move = &radeon_bo_move,
 426         .verify_access = &radeon_verify_access,
 427         .sync_obj_signaled = &radeon_sync_obj_signaled,
 428         .sync_obj_wait = &radeon_sync_obj_wait,
 429         .sync_obj_flush = &radeon_sync_obj_flush,
 430         .sync_obj_unref = &radeon_sync_obj_unref,
 431         .sync_obj_ref = &radeon_sync_obj_ref,
 432 };
 433
 434 int radeon_ttm_init(struct radeon_device *rdev)
 435 {
 436         int r;
 437
 438         r = radeon_ttm_global_init(rdev);
 439         if (r) {
 440                 return r;
 441         }
 442         /* No others user of address space so set it to 0 */
 443         r = ttm_bo_device_init(&rdev->mman.bdev,
 444                                rdev->mman.mem_global_ref.object,
 445                                &radeon_bo_driver, DRM_FILE_PAGE_OFFSET);
 446         if (r) {
 447                 DRM_ERROR("failed initializing buffer object driver(%d).\n", r);
 448                 return r;
 449         }
 450         r = ttm_bo_init_mm(&rdev->mman.bdev, TTM_PL_VRAM, 0,
 451                            ((rdev->mc.aper_size) >> PAGE_SHIFT));
 452         if (r) {
 453                 DRM_ERROR("Failed initializing VRAM heap.\n");
 454                 return r;
 455         }
 456         r = radeon_object_create(rdev, NULL, 256 * 1024, true,
 457                                  RADEON_GEM_DOMAIN_VRAM, false,
 458                                  &rdev->stollen_vga_memory);
 459         if (r) {
 460                 return r;
 461         }
 462         r = radeon_object_pin(rdev->stollen_vga_memory, RADEON_GEM_DOMAIN_VRAM, NULL);
 463         if (r) {
 464                 radeon_object_unref(&rdev->stollen_vga_memory);
 465                 return r;
 466         }
 467         DRM_INFO("radeon: %uM of VRAM memory ready\n",
 468                  rdev->mc.vram_size / (1024 * 1024));
 469         r = ttm_bo_init_mm(&rdev->mman.bdev, TTM_PL_TT, 0,
 470                            ((rdev->mc.gtt_size) >> PAGE_SHIFT));
 471         if (r) {
 472                 DRM_ERROR("Failed initializing GTT heap.\n");
 473                 return r;
 474         }
 475         DRM_INFO("radeon: %uM of GTT memory ready.\n",
 476                  rdev->mc.gtt_size / (1024 * 1024));
 477         if (unlikely(rdev->mman.bdev.dev_mapping == NULL)) {
 478                 rdev->mman.bdev.dev_mapping = rdev->ddev->dev_mapping;
 479         }
 480         return 0;
 481 }
 482
 483 void radeon_ttm_fini(struct radeon_device *rdev)
 484 {
 485         if (rdev->stollen_vga_memory) {
 486                 radeon_object_unpin(rdev->stollen_vga_memory);
 487                 radeon_object_unref(&rdev->stollen_vga_memory);
 488         }
 489         ttm_bo_clean_mm(&rdev->mman.bdev, TTM_PL_VRAM);
 490         ttm_bo_clean_mm(&rdev->mman.bdev, TTM_PL_TT);
 491         ttm_bo_device_release(&rdev->mman.bdev);
 492         radeon_gart_fini(rdev);
 493         radeon_ttm_global_fini(rdev);
 494         DRM_INFO("radeon: ttm finalized\n");
 495 }
 496
 497 static struct vm_operations_struct radeon_ttm_vm_ops;
 498 static struct vm_operations_struct *ttm_vm_ops = NULL;
 499
 500 static int radeon_ttm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 501 {
 502         struct ttm_buffer_object *bo;
 503         int r;
 504
 505         bo = (struct ttm_buffer_object *)vma->vm_private_data;
 506         if (bo == NULL) {
 507                 return VM_FAULT_NOPAGE;
 508         }
 509         r = ttm_vm_ops->fault(vma, vmf);
 510         return r;
 511 }
 512
 513 int radeon_mmap(struct file *filp, struct vm_area_struct *vma)
 514 {
 515         struct drm_file *file_priv;
 516         struct radeon_device *rdev;
 517         int r;
 518
 519         if (unlikely(vma->vm_pgoff < DRM_FILE_PAGE_OFFSET)) {
 520                 return drm_mmap(filp, vma);
 521         }
 522
 523         file_priv = (struct drm_file *)filp->private_data;
 524         rdev = file_priv->minor->dev->dev_private;
 525         if (rdev == NULL) {
 526                 return -EINVAL;
 527         }
 528         r = ttm_bo_mmap(filp, vma, &rdev->mman.bdev);
 529         if (unlikely(r != 0)) {
 530                 return r;
 531         }
 532         if (unlikely(ttm_vm_ops == NULL)) {
 533                 ttm_vm_ops = vma->vm_ops;
 534                 radeon_ttm_vm_ops = *ttm_vm_ops;
 535                 radeon_ttm_vm_ops.fault = &radeon_ttm_fault;
 536         }
 537         vma->vm_ops = &radeon_ttm_vm_ops;
 538         return 0;
 539 }
 540
 541
 542 /*
 543  * TTM backend functions.
 544  */
 545 struct radeon_ttm_backend {
 546         struct ttm_backend              backend;
 547         struct radeon_device            *rdev;
 548         unsigned long                   num_pages;
 549         struct page                     **pages;
 550         struct page                     *dummy_read_page;
 551         bool                            populated;
 552         bool                            bound;
 553         unsigned                        offset;
 554 };
 555
 556 static int radeon_ttm_backend_populate(struct ttm_backend *backend,
 557                                        unsigned long num_pages,
 558                                        struct page **pages,
 559                                        struct page *dummy_read_page)
 560 {
 561         struct radeon_ttm_backend *gtt;
 562
 563         gtt = container_of(backend, struct radeon_ttm_backend, backend);
 564         gtt->pages = pages;
 565         gtt->num_pages = num_pages;
 566         gtt->dummy_read_page = dummy_read_page;
 567         gtt->populated = true;
 568         return 0;
 569 }
 570
 571 static void radeon_ttm_backend_clear(struct ttm_backend *backend)
 572 {
 573         struct radeon_ttm_backend *gtt;
 574
 575         gtt = container_of(backend, struct radeon_ttm_backend, backend);
 576         gtt->pages = NULL;
 577         gtt->num_pages = 0;
 578         gtt->dummy_read_page = NULL;
 579         gtt->populated = false;
 580         gtt->bound = false;
 581 }
 582
 583
 584 static int radeon_ttm_backend_bind(struct ttm_backend *backend,
 585                                    struct ttm_mem_reg *bo_mem)
 586 {
 587         struct radeon_ttm_backend *gtt;
 588         int r;
 589
 590         gtt = container_of(backend, struct radeon_ttm_backend, backend);
 591         gtt->offset = bo_mem->mm_node->start << PAGE_SHIFT;
 592         if (!gtt->num_pages) {
 593                 WARN(1, "nothing to bind %lu pages for mreg %p back %p!\n", gtt->num_pages, bo_mem, backend);
 594         }
 595         r = radeon_gart_bind(gtt->rdev, gtt->offset,
 596                              gtt->num_pages, gtt->pages);
 597         if (r) {
 598                 DRM_ERROR("failed to bind %lu pages at 0x%08X\n",
 599                           gtt->num_pages, gtt->offset);
 600                 return r;
 601         }
 602         gtt->bound = true;
 603         return 0;
 604 }
 605
 606 static int radeon_ttm_backend_unbind(struct ttm_backend *backend)
 607 {
 608         struct radeon_ttm_backend *gtt;
 609
 610         gtt = container_of(backend, struct radeon_ttm_backend, backend);
 611         radeon_gart_unbind(gtt->rdev, gtt->offset, gtt->num_pages);
 612         gtt->bound = false;
 613         return 0;
 614 }
 615
 616 static void radeon_ttm_backend_destroy(struct ttm_backend *backend)
 617 {
 618         struct radeon_ttm_backend *gtt;
 619
 620         gtt = container_of(backend, struct radeon_ttm_backend, backend);
 621         if (gtt->bound) {
 622                 radeon_ttm_backend_unbind(backend);
 623         }
 624         kfree(gtt);
 625 }
 626
 627 static struct ttm_backend_func radeon_backend_func = {
 628         .populate = &radeon_ttm_backend_populate,
 629         .clear = &radeon_ttm_backend_clear,
 630         .bind = &radeon_ttm_backend_bind,
 631         .unbind = &radeon_ttm_backend_unbind,
 632         .destroy = &radeon_ttm_backend_destroy,
 633 };
 634
 635 struct ttm_backend *radeon_ttm_backend_create(struct radeon_device *rdev)
 636 {
 637         struct radeon_ttm_backend *gtt;
 638
 639         gtt = kzalloc(sizeof(struct radeon_ttm_backend), GFP_KERNEL);
 640         if (gtt == NULL) {
 641                 return NULL;
 642         }
 643         gtt->backend.bdev = &rdev->mman.bdev;
 644         gtt->backend.flags = 0;
 645         gtt->backend.func = &radeon_backend_func;
 646         gtt->rdev = rdev;
 647         gtt->pages = NULL;
 648         gtt->num_pages = 0;
 649         gtt->dummy_read_page = NULL;
 650         gtt->populated = false;
 651         gtt->bound = false;
 652         return &gtt->backend;
 653 }