1 // SPDX-License-Identifier: MIT 2 /* 3 * Copyright © 2021 Intel Corporation 4 */ 5 6 #include <linux/shmem_fs.h> 7 8 #include <drm/ttm/ttm_bo_driver.h> 9 #include <drm/ttm/ttm_placement.h> 10 #include <drm/drm_buddy.h> 11 12 #include "i915_drv.h" 13 #include "i915_ttm_buddy_manager.h" 14 #include "intel_memory_region.h" 15 #include "intel_region_ttm.h" 16 17 #include "gem/i915_gem_mman.h" 18 #include "gem/i915_gem_object.h" 19 #include "gem/i915_gem_region.h" 20 #include "gem/i915_gem_ttm.h" 21 #include "gem/i915_gem_ttm_move.h" 22 #include "gem/i915_gem_ttm_pm.h" 23 #include "gt/intel_gpu_commands.h" 24 25 #define I915_TTM_PRIO_PURGE 0 26 #define I915_TTM_PRIO_NO_PAGES 1 27 #define I915_TTM_PRIO_HAS_PAGES 2 28 #define I915_TTM_PRIO_NEEDS_CPU_ACCESS 3 29 30 /* 31 * Size of struct ttm_place vector in on-stack struct ttm_placement allocs 32 */ 33 #define I915_TTM_MAX_PLACEMENTS INTEL_REGION_UNKNOWN 34 35 /** 36 * struct i915_ttm_tt - TTM page vector with additional private information 37 * @ttm: The base TTM page vector. 38 * @dev: The struct device used for dma mapping and unmapping. 39 * @cached_rsgt: The cached scatter-gather table. 40 * @is_shmem: Set if using shmem. 41 * @filp: The shmem file, if using shmem backend. 42 * 43 * Note that DMA may be going on right up to the point where the page- 44 * vector is unpopulated in delayed destroy. Hence keep the 45 * scatter-gather table mapped and cached up to that point. This is 46 * different from the cached gem object io scatter-gather table which 47 * doesn't have an associated dma mapping. 48 */ 49 struct i915_ttm_tt { 50 struct ttm_tt ttm; 51 struct device *dev; 52 struct i915_refct_sgt cached_rsgt; 53 54 bool is_shmem; 55 struct file *filp; 56 }; 57 58 static const struct ttm_place sys_placement_flags = { 59 .fpfn = 0, 60 .lpfn = 0, 61 .mem_type = I915_PL_SYSTEM, 62 .flags = 0, 63 }; 64 65 static struct ttm_placement i915_sys_placement = { 66 .num_placement = 1, 67 .placement = &sys_placement_flags, 68 .num_busy_placement = 1, 69 .busy_placement = &sys_placement_flags, 70 }; 71 72 /** 73 * i915_ttm_sys_placement - Return the struct ttm_placement to be 74 * used for an object in system memory. 75 * 76 * Rather than making the struct extern, use this 77 * function. 78 * 79 * Return: A pointer to a static variable for sys placement. 80 */ 81 struct ttm_placement *i915_ttm_sys_placement(void) 82 { 83 return &i915_sys_placement; 84 } 85 86 static int i915_ttm_err_to_gem(int err) 87 { 88 /* Fastpath */ 89 if (likely(!err)) 90 return 0; 91 92 switch (err) { 93 case -EBUSY: 94 /* 95 * TTM likes to convert -EDEADLK to -EBUSY, and wants us to 96 * restart the operation, since we don't record the contending 97 * lock. We use -EAGAIN to restart. 98 */ 99 return -EAGAIN; 100 case -ENOSPC: 101 /* 102 * Memory type / region is full, and we can't evict. 103 * Except possibly system, that returns -ENOMEM; 104 */ 105 return -ENXIO; 106 default: 107 break; 108 } 109 110 return err; 111 } 112 113 static enum ttm_caching 114 i915_ttm_select_tt_caching(const struct drm_i915_gem_object *obj) 115 { 116 /* 117 * Objects only allowed in system get cached cpu-mappings, or when 118 * evicting lmem-only buffers to system for swapping. Other objects get 119 * WC mapping for now. Even if in system. 120 */ 121 if (obj->mm.n_placements <= 1) 122 return ttm_cached; 123 124 return ttm_write_combined; 125 } 126 127 static void 128 i915_ttm_place_from_region(const struct intel_memory_region *mr, 129 struct ttm_place *place, 130 resource_size_t offset, 131 resource_size_t size, 132 unsigned int flags) 133 { 134 memset(place, 0, sizeof(*place)); 135 place->mem_type = intel_region_to_ttm_type(mr); 136 137 if (mr->type == INTEL_MEMORY_SYSTEM) 138 return; 139 140 if (flags & I915_BO_ALLOC_CONTIGUOUS) 141 place->flags |= TTM_PL_FLAG_CONTIGUOUS; 142 if (offset != I915_BO_INVALID_OFFSET) { 143 place->fpfn = offset >> PAGE_SHIFT; 144 place->lpfn = place->fpfn + (size >> PAGE_SHIFT); 145 } else if (mr->io_size && mr->io_size < mr->total) { 146 if (flags & I915_BO_ALLOC_GPU_ONLY) { 147 place->flags |= TTM_PL_FLAG_TOPDOWN; 148 } else { 149 place->fpfn = 0; 150 place->lpfn = mr->io_size >> PAGE_SHIFT; 151 } 152 } 153 } 154 155 static void 156 i915_ttm_placement_from_obj(const struct drm_i915_gem_object *obj, 157 struct ttm_place *requested, 158 struct ttm_place *busy, 159 struct ttm_placement *placement) 160 { 161 unsigned int num_allowed = obj->mm.n_placements; 162 unsigned int flags = obj->flags; 163 unsigned int i; 164 165 placement->num_placement = 1; 166 i915_ttm_place_from_region(num_allowed ? obj->mm.placements[0] : 167 obj->mm.region, requested, obj->bo_offset, 168 obj->base.size, flags); 169 170 /* Cache this on object? */ 171 placement->num_busy_placement = num_allowed; 172 for (i = 0; i < placement->num_busy_placement; ++i) 173 i915_ttm_place_from_region(obj->mm.placements[i], busy + i, 174 obj->bo_offset, obj->base.size, flags); 175 176 if (num_allowed == 0) { 177 *busy = *requested; 178 placement->num_busy_placement = 1; 179 } 180 181 placement->placement = requested; 182 placement->busy_placement = busy; 183 } 184 185 static int i915_ttm_tt_shmem_populate(struct ttm_device *bdev, 186 struct ttm_tt *ttm, 187 struct ttm_operation_ctx *ctx) 188 { 189 struct drm_i915_private *i915 = container_of(bdev, typeof(*i915), bdev); 190 struct intel_memory_region *mr = i915->mm.regions[INTEL_MEMORY_SYSTEM]; 191 struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm); 192 const unsigned int max_segment = i915_sg_segment_size(i915->drm.dev); 193 const size_t size = (size_t)ttm->num_pages << PAGE_SHIFT; 194 struct file *filp = i915_tt->filp; 195 struct sgt_iter sgt_iter; 196 struct sg_table *st; 197 struct page *page; 198 unsigned long i; 199 int err; 200 201 if (!filp) { 202 struct address_space *mapping; 203 gfp_t mask; 204 205 filp = shmem_file_setup("i915-shmem-tt", size, VM_NORESERVE); 206 if (IS_ERR(filp)) 207 return PTR_ERR(filp); 208 209 mask = GFP_HIGHUSER | __GFP_RECLAIMABLE; 210 211 mapping = filp->f_mapping; 212 mapping_set_gfp_mask(mapping, mask); 213 GEM_BUG_ON(!(mapping_gfp_mask(mapping) & __GFP_RECLAIM)); 214 215 i915_tt->filp = filp; 216 } 217 218 st = &i915_tt->cached_rsgt.table; 219 err = shmem_sg_alloc_table(i915, st, size, mr, filp->f_mapping, 220 max_segment); 221 if (err) 222 return err; 223 224 err = dma_map_sgtable(i915_tt->dev, st, DMA_BIDIRECTIONAL, 225 DMA_ATTR_SKIP_CPU_SYNC); 226 if (err) 227 goto err_free_st; 228 229 i = 0; 230 for_each_sgt_page(page, sgt_iter, st) 231 ttm->pages[i++] = page; 232 233 if (ttm->page_flags & TTM_TT_FLAG_SWAPPED) 234 ttm->page_flags &= ~TTM_TT_FLAG_SWAPPED; 235 236 return 0; 237 238 err_free_st: 239 shmem_sg_free_table(st, filp->f_mapping, false, false); 240 241 return err; 242 } 243 244 static void i915_ttm_tt_shmem_unpopulate(struct ttm_tt *ttm) 245 { 246 struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm); 247 bool backup = ttm->page_flags & TTM_TT_FLAG_SWAPPED; 248 struct sg_table *st = &i915_tt->cached_rsgt.table; 249 250 shmem_sg_free_table(st, file_inode(i915_tt->filp)->i_mapping, 251 backup, backup); 252 } 253 254 static void i915_ttm_tt_release(struct kref *ref) 255 { 256 struct i915_ttm_tt *i915_tt = 257 container_of(ref, typeof(*i915_tt), cached_rsgt.kref); 258 struct sg_table *st = &i915_tt->cached_rsgt.table; 259 260 GEM_WARN_ON(st->sgl); 261 262 kfree(i915_tt); 263 } 264 265 static const struct i915_refct_sgt_ops tt_rsgt_ops = { 266 .release = i915_ttm_tt_release 267 }; 268 269 static struct ttm_tt *i915_ttm_tt_create(struct ttm_buffer_object *bo, 270 uint32_t page_flags) 271 { 272 struct drm_i915_private *i915 = container_of(bo->bdev, typeof(*i915), 273 bdev); 274 struct ttm_resource_manager *man = 275 ttm_manager_type(bo->bdev, bo->resource->mem_type); 276 struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); 277 unsigned long ccs_pages = 0; 278 enum ttm_caching caching; 279 struct i915_ttm_tt *i915_tt; 280 int ret; 281 282 if (i915_ttm_is_ghost_object(bo)) 283 return NULL; 284 285 i915_tt = kzalloc(sizeof(*i915_tt), GFP_KERNEL); 286 if (!i915_tt) 287 return NULL; 288 289 if (obj->flags & I915_BO_ALLOC_CPU_CLEAR && 290 man->use_tt) 291 page_flags |= TTM_TT_FLAG_ZERO_ALLOC; 292 293 caching = i915_ttm_select_tt_caching(obj); 294 if (i915_gem_object_is_shrinkable(obj) && caching == ttm_cached) { 295 page_flags |= TTM_TT_FLAG_EXTERNAL | 296 TTM_TT_FLAG_EXTERNAL_MAPPABLE; 297 i915_tt->is_shmem = true; 298 } 299 300 if (i915_gem_object_needs_ccs_pages(obj)) 301 ccs_pages = DIV_ROUND_UP(DIV_ROUND_UP(bo->base.size, 302 NUM_BYTES_PER_CCS_BYTE), 303 PAGE_SIZE); 304 305 ret = ttm_tt_init(&i915_tt->ttm, bo, page_flags, caching, ccs_pages); 306 if (ret) 307 goto err_free; 308 309 __i915_refct_sgt_init(&i915_tt->cached_rsgt, bo->base.size, 310 &tt_rsgt_ops); 311 312 i915_tt->dev = obj->base.dev->dev; 313 314 return &i915_tt->ttm; 315 316 err_free: 317 kfree(i915_tt); 318 return NULL; 319 } 320 321 static int i915_ttm_tt_populate(struct ttm_device *bdev, 322 struct ttm_tt *ttm, 323 struct ttm_operation_ctx *ctx) 324 { 325 struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm); 326 327 if (i915_tt->is_shmem) 328 return i915_ttm_tt_shmem_populate(bdev, ttm, ctx); 329 330 return ttm_pool_alloc(&bdev->pool, ttm, ctx); 331 } 332 333 static void i915_ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm) 334 { 335 struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm); 336 struct sg_table *st = &i915_tt->cached_rsgt.table; 337 338 if (st->sgl) 339 dma_unmap_sgtable(i915_tt->dev, st, DMA_BIDIRECTIONAL, 0); 340 341 if (i915_tt->is_shmem) { 342 i915_ttm_tt_shmem_unpopulate(ttm); 343 } else { 344 sg_free_table(st); 345 ttm_pool_free(&bdev->pool, ttm); 346 } 347 } 348 349 static void i915_ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *ttm) 350 { 351 struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm); 352 353 if (i915_tt->filp) 354 fput(i915_tt->filp); 355 356 ttm_tt_fini(ttm); 357 i915_refct_sgt_put(&i915_tt->cached_rsgt); 358 } 359 360 static bool i915_ttm_eviction_valuable(struct ttm_buffer_object *bo, 361 const struct ttm_place *place) 362 { 363 struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); 364 365 if (i915_ttm_is_ghost_object(bo)) 366 return false; 367 368 /* 369 * EXTERNAL objects should never be swapped out by TTM, instead we need 370 * to handle that ourselves. TTM will already skip such objects for us, 371 * but we would like to avoid grabbing locks for no good reason. 372 */ 373 if (bo->ttm && bo->ttm->page_flags & TTM_TT_FLAG_EXTERNAL) 374 return false; 375 376 /* Will do for now. Our pinned objects are still on TTM's LRU lists */ 377 if (!i915_gem_object_evictable(obj)) 378 return false; 379 380 return ttm_bo_eviction_valuable(bo, place); 381 } 382 383 static void i915_ttm_evict_flags(struct ttm_buffer_object *bo, 384 struct ttm_placement *placement) 385 { 386 *placement = i915_sys_placement; 387 } 388 389 /** 390 * i915_ttm_free_cached_io_rsgt - Free object cached LMEM information 391 * @obj: The GEM object 392 * This function frees any LMEM-related information that is cached on 393 * the object. For example the radix tree for fast page lookup and the 394 * cached refcounted sg-table 395 */ 396 void i915_ttm_free_cached_io_rsgt(struct drm_i915_gem_object *obj) 397 { 398 struct radix_tree_iter iter; 399 void __rcu **slot; 400 401 if (!obj->ttm.cached_io_rsgt) 402 return; 403 404 rcu_read_lock(); 405 radix_tree_for_each_slot(slot, &obj->ttm.get_io_page.radix, &iter, 0) 406 radix_tree_delete(&obj->ttm.get_io_page.radix, iter.index); 407 rcu_read_unlock(); 408 409 i915_refct_sgt_put(obj->ttm.cached_io_rsgt); 410 obj->ttm.cached_io_rsgt = NULL; 411 } 412 413 /** 414 * i915_ttm_purge - Clear an object of its memory 415 * @obj: The object 416 * 417 * This function is called to clear an object of it's memory when it is 418 * marked as not needed anymore. 419 * 420 * Return: 0 on success, negative error code on failure. 421 */ 422 int i915_ttm_purge(struct drm_i915_gem_object *obj) 423 { 424 struct ttm_buffer_object *bo = i915_gem_to_ttm(obj); 425 struct i915_ttm_tt *i915_tt = 426 container_of(bo->ttm, typeof(*i915_tt), ttm); 427 struct ttm_operation_ctx ctx = { 428 .interruptible = true, 429 .no_wait_gpu = false, 430 }; 431 struct ttm_placement place = {}; 432 int ret; 433 434 if (obj->mm.madv == __I915_MADV_PURGED) 435 return 0; 436 437 ret = ttm_bo_validate(bo, &place, &ctx); 438 if (ret) 439 return ret; 440 441 if (bo->ttm && i915_tt->filp) { 442 /* 443 * The below fput(which eventually calls shmem_truncate) might 444 * be delayed by worker, so when directly called to purge the 445 * pages(like by the shrinker) we should try to be more 446 * aggressive and release the pages immediately. 447 */ 448 shmem_truncate_range(file_inode(i915_tt->filp), 449 0, (loff_t)-1); 450 fput(fetch_and_zero(&i915_tt->filp)); 451 } 452 453 obj->write_domain = 0; 454 obj->read_domains = 0; 455 i915_ttm_adjust_gem_after_move(obj); 456 i915_ttm_free_cached_io_rsgt(obj); 457 obj->mm.madv = __I915_MADV_PURGED; 458 459 return 0; 460 } 461 462 static int i915_ttm_shrink(struct drm_i915_gem_object *obj, unsigned int flags) 463 { 464 struct ttm_buffer_object *bo = i915_gem_to_ttm(obj); 465 struct i915_ttm_tt *i915_tt = 466 container_of(bo->ttm, typeof(*i915_tt), ttm); 467 struct ttm_operation_ctx ctx = { 468 .interruptible = true, 469 .no_wait_gpu = flags & I915_GEM_OBJECT_SHRINK_NO_GPU_WAIT, 470 }; 471 struct ttm_placement place = {}; 472 int ret; 473 474 if (!bo->ttm || bo->resource->mem_type != TTM_PL_SYSTEM) 475 return 0; 476 477 GEM_BUG_ON(!i915_tt->is_shmem); 478 479 if (!i915_tt->filp) 480 return 0; 481 482 ret = ttm_bo_wait_ctx(bo, &ctx); 483 if (ret) 484 return ret; 485 486 switch (obj->mm.madv) { 487 case I915_MADV_DONTNEED: 488 return i915_ttm_purge(obj); 489 case __I915_MADV_PURGED: 490 return 0; 491 } 492 493 if (bo->ttm->page_flags & TTM_TT_FLAG_SWAPPED) 494 return 0; 495 496 bo->ttm->page_flags |= TTM_TT_FLAG_SWAPPED; 497 ret = ttm_bo_validate(bo, &place, &ctx); 498 if (ret) { 499 bo->ttm->page_flags &= ~TTM_TT_FLAG_SWAPPED; 500 return ret; 501 } 502 503 if (flags & I915_GEM_OBJECT_SHRINK_WRITEBACK) 504 __shmem_writeback(obj->base.size, i915_tt->filp->f_mapping); 505 506 return 0; 507 } 508 509 static void i915_ttm_delete_mem_notify(struct ttm_buffer_object *bo) 510 { 511 struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); 512 513 if (bo->resource && !i915_ttm_is_ghost_object(bo)) { 514 __i915_gem_object_pages_fini(obj); 515 i915_ttm_free_cached_io_rsgt(obj); 516 } 517 } 518 519 static struct i915_refct_sgt *i915_ttm_tt_get_st(struct ttm_tt *ttm) 520 { 521 struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm); 522 struct sg_table *st; 523 int ret; 524 525 if (i915_tt->cached_rsgt.table.sgl) 526 return i915_refct_sgt_get(&i915_tt->cached_rsgt); 527 528 st = &i915_tt->cached_rsgt.table; 529 ret = sg_alloc_table_from_pages_segment(st, 530 ttm->pages, ttm->num_pages, 531 0, (unsigned long)ttm->num_pages << PAGE_SHIFT, 532 i915_sg_segment_size(i915_tt->dev), GFP_KERNEL); 533 if (ret) { 534 st->sgl = NULL; 535 return ERR_PTR(ret); 536 } 537 538 ret = dma_map_sgtable(i915_tt->dev, st, DMA_BIDIRECTIONAL, 0); 539 if (ret) { 540 sg_free_table(st); 541 return ERR_PTR(ret); 542 } 543 544 return i915_refct_sgt_get(&i915_tt->cached_rsgt); 545 } 546 547 /** 548 * i915_ttm_resource_get_st - Get a refcounted sg-table pointing to the 549 * resource memory 550 * @obj: The GEM object used for sg-table caching 551 * @res: The struct ttm_resource for which an sg-table is requested. 552 * 553 * This function returns a refcounted sg-table representing the memory 554 * pointed to by @res. If @res is the object's current resource it may also 555 * cache the sg_table on the object or attempt to access an already cached 556 * sg-table. The refcounted sg-table needs to be put when no-longer in use. 557 * 558 * Return: A valid pointer to a struct i915_refct_sgt or error pointer on 559 * failure. 560 */ 561 struct i915_refct_sgt * 562 i915_ttm_resource_get_st(struct drm_i915_gem_object *obj, 563 struct ttm_resource *res) 564 { 565 struct ttm_buffer_object *bo = i915_gem_to_ttm(obj); 566 u32 page_alignment; 567 568 if (!i915_ttm_gtt_binds_lmem(res)) 569 return i915_ttm_tt_get_st(bo->ttm); 570 571 page_alignment = bo->page_alignment << PAGE_SHIFT; 572 if (!page_alignment) 573 page_alignment = obj->mm.region->min_page_size; 574 575 /* 576 * If CPU mapping differs, we need to add the ttm_tt pages to 577 * the resulting st. Might make sense for GGTT. 578 */ 579 GEM_WARN_ON(!i915_ttm_cpu_maps_iomem(res)); 580 if (bo->resource == res) { 581 if (!obj->ttm.cached_io_rsgt) { 582 struct i915_refct_sgt *rsgt; 583 584 rsgt = intel_region_ttm_resource_to_rsgt(obj->mm.region, 585 res, 586 page_alignment); 587 if (IS_ERR(rsgt)) 588 return rsgt; 589 590 obj->ttm.cached_io_rsgt = rsgt; 591 } 592 return i915_refct_sgt_get(obj->ttm.cached_io_rsgt); 593 } 594 595 return intel_region_ttm_resource_to_rsgt(obj->mm.region, res, 596 page_alignment); 597 } 598 599 static int i915_ttm_truncate(struct drm_i915_gem_object *obj) 600 { 601 struct ttm_buffer_object *bo = i915_gem_to_ttm(obj); 602 int err; 603 604 WARN_ON_ONCE(obj->mm.madv == I915_MADV_WILLNEED); 605 606 err = i915_ttm_move_notify(bo); 607 if (err) 608 return err; 609 610 return i915_ttm_purge(obj); 611 } 612 613 static void i915_ttm_swap_notify(struct ttm_buffer_object *bo) 614 { 615 struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); 616 int ret; 617 618 if (i915_ttm_is_ghost_object(bo)) 619 return; 620 621 ret = i915_ttm_move_notify(bo); 622 GEM_WARN_ON(ret); 623 GEM_WARN_ON(obj->ttm.cached_io_rsgt); 624 if (!ret && obj->mm.madv != I915_MADV_WILLNEED) 625 i915_ttm_purge(obj); 626 } 627 628 /** 629 * i915_ttm_resource_mappable - Return true if the ttm resource is CPU 630 * accessible. 631 * @res: The TTM resource to check. 632 * 633 * This is interesting on small-BAR systems where we may encounter lmem objects 634 * that can't be accessed via the CPU. 635 */ 636 bool i915_ttm_resource_mappable(struct ttm_resource *res) 637 { 638 struct i915_ttm_buddy_resource *bman_res = to_ttm_buddy_resource(res); 639 640 if (!i915_ttm_cpu_maps_iomem(res)) 641 return true; 642 643 return bman_res->used_visible_size == PFN_UP(bman_res->base.size); 644 } 645 646 static int i915_ttm_io_mem_reserve(struct ttm_device *bdev, struct ttm_resource *mem) 647 { 648 struct drm_i915_gem_object *obj = i915_ttm_to_gem(mem->bo); 649 bool unknown_state; 650 651 if (i915_ttm_is_ghost_object(mem->bo)) 652 return -EINVAL; 653 654 if (!kref_get_unless_zero(&obj->base.refcount)) 655 return -EINVAL; 656 657 assert_object_held(obj); 658 659 unknown_state = i915_gem_object_has_unknown_state(obj); 660 i915_gem_object_put(obj); 661 if (unknown_state) 662 return -EINVAL; 663 664 if (!i915_ttm_cpu_maps_iomem(mem)) 665 return 0; 666 667 if (!i915_ttm_resource_mappable(mem)) 668 return -EINVAL; 669 670 mem->bus.caching = ttm_write_combined; 671 mem->bus.is_iomem = true; 672 673 return 0; 674 } 675 676 static unsigned long i915_ttm_io_mem_pfn(struct ttm_buffer_object *bo, 677 unsigned long page_offset) 678 { 679 struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); 680 struct scatterlist *sg; 681 unsigned long base; 682 unsigned int ofs; 683 684 GEM_BUG_ON(i915_ttm_is_ghost_object(bo)); 685 GEM_WARN_ON(bo->ttm); 686 687 base = obj->mm.region->iomap.base - obj->mm.region->region.start; 688 sg = __i915_gem_object_get_sg(obj, &obj->ttm.get_io_page, page_offset, &ofs, true); 689 690 return ((base + sg_dma_address(sg)) >> PAGE_SHIFT) + ofs; 691 } 692 693 static int i915_ttm_access_memory(struct ttm_buffer_object *bo, 694 unsigned long offset, void *buf, 695 int len, int write) 696 { 697 struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); 698 resource_size_t iomap = obj->mm.region->iomap.base - 699 obj->mm.region->region.start; 700 unsigned long page = offset >> PAGE_SHIFT; 701 unsigned long bytes_left = len; 702 703 /* 704 * TODO: For now just let it fail if the resource is non-mappable, 705 * otherwise we need to perform the memcpy from the gpu here, without 706 * interfering with the object (like moving the entire thing). 707 */ 708 if (!i915_ttm_resource_mappable(bo->resource)) 709 return -EIO; 710 711 offset -= page << PAGE_SHIFT; 712 do { 713 unsigned long bytes = min(bytes_left, PAGE_SIZE - offset); 714 void __iomem *ptr; 715 dma_addr_t daddr; 716 717 daddr = i915_gem_object_get_dma_address(obj, page); 718 ptr = ioremap_wc(iomap + daddr + offset, bytes); 719 if (!ptr) 720 return -EIO; 721 722 if (write) 723 memcpy_toio(ptr, buf, bytes); 724 else 725 memcpy_fromio(buf, ptr, bytes); 726 iounmap(ptr); 727 728 page++; 729 buf += bytes; 730 bytes_left -= bytes; 731 offset = 0; 732 } while (bytes_left); 733 734 return len; 735 } 736 737 /* 738 * All callbacks need to take care not to downcast a struct ttm_buffer_object 739 * without checking its subclass, since it might be a TTM ghost object. 740 */ 741 static struct ttm_device_funcs i915_ttm_bo_driver = { 742 .ttm_tt_create = i915_ttm_tt_create, 743 .ttm_tt_populate = i915_ttm_tt_populate, 744 .ttm_tt_unpopulate = i915_ttm_tt_unpopulate, 745 .ttm_tt_destroy = i915_ttm_tt_destroy, 746 .eviction_valuable = i915_ttm_eviction_valuable, 747 .evict_flags = i915_ttm_evict_flags, 748 .move = i915_ttm_move, 749 .swap_notify = i915_ttm_swap_notify, 750 .delete_mem_notify = i915_ttm_delete_mem_notify, 751 .io_mem_reserve = i915_ttm_io_mem_reserve, 752 .io_mem_pfn = i915_ttm_io_mem_pfn, 753 .access_memory = i915_ttm_access_memory, 754 }; 755 756 /** 757 * i915_ttm_driver - Return a pointer to the TTM device funcs 758 * 759 * Return: Pointer to statically allocated TTM device funcs. 760 */ 761 struct ttm_device_funcs *i915_ttm_driver(void) 762 { 763 return &i915_ttm_bo_driver; 764 } 765 766 static int __i915_ttm_get_pages(struct drm_i915_gem_object *obj, 767 struct ttm_placement *placement) 768 { 769 struct ttm_buffer_object *bo = i915_gem_to_ttm(obj); 770 struct ttm_operation_ctx ctx = { 771 .interruptible = true, 772 .no_wait_gpu = false, 773 }; 774 int real_num_busy; 775 int ret; 776 777 /* First try only the requested placement. No eviction. */ 778 real_num_busy = fetch_and_zero(&placement->num_busy_placement); 779 ret = ttm_bo_validate(bo, placement, &ctx); 780 if (ret) { 781 ret = i915_ttm_err_to_gem(ret); 782 /* 783 * Anything that wants to restart the operation gets to 784 * do that. 785 */ 786 if (ret == -EDEADLK || ret == -EINTR || ret == -ERESTARTSYS || 787 ret == -EAGAIN) 788 return ret; 789 790 /* 791 * If the initial attempt fails, allow all accepted placements, 792 * evicting if necessary. 793 */ 794 placement->num_busy_placement = real_num_busy; 795 ret = ttm_bo_validate(bo, placement, &ctx); 796 if (ret) 797 return i915_ttm_err_to_gem(ret); 798 } 799 800 if (bo->ttm && !ttm_tt_is_populated(bo->ttm)) { 801 ret = ttm_tt_populate(bo->bdev, bo->ttm, &ctx); 802 if (ret) 803 return ret; 804 805 i915_ttm_adjust_domains_after_move(obj); 806 i915_ttm_adjust_gem_after_move(obj); 807 } 808 809 if (!i915_gem_object_has_pages(obj)) { 810 struct i915_refct_sgt *rsgt = 811 i915_ttm_resource_get_st(obj, bo->resource); 812 813 if (IS_ERR(rsgt)) 814 return PTR_ERR(rsgt); 815 816 GEM_BUG_ON(obj->mm.rsgt); 817 obj->mm.rsgt = rsgt; 818 __i915_gem_object_set_pages(obj, &rsgt->table, 819 i915_sg_dma_sizes(rsgt->table.sgl)); 820 } 821 822 GEM_BUG_ON(bo->ttm && ((obj->base.size >> PAGE_SHIFT) < bo->ttm->num_pages)); 823 i915_ttm_adjust_lru(obj); 824 return ret; 825 } 826 827 static int i915_ttm_get_pages(struct drm_i915_gem_object *obj) 828 { 829 struct ttm_place requested, busy[I915_TTM_MAX_PLACEMENTS]; 830 struct ttm_placement placement; 831 832 GEM_BUG_ON(obj->mm.n_placements > I915_TTM_MAX_PLACEMENTS); 833 834 /* Move to the requested placement. */ 835 i915_ttm_placement_from_obj(obj, &requested, busy, &placement); 836 837 return __i915_ttm_get_pages(obj, &placement); 838 } 839 840 /** 841 * DOC: Migration vs eviction 842 * 843 * GEM migration may not be the same as TTM migration / eviction. If 844 * the TTM core decides to evict an object it may be evicted to a 845 * TTM memory type that is not in the object's allowable GEM regions, or 846 * in fact theoretically to a TTM memory type that doesn't correspond to 847 * a GEM memory region. In that case the object's GEM region is not 848 * updated, and the data is migrated back to the GEM region at 849 * get_pages time. TTM may however set up CPU ptes to the object even 850 * when it is evicted. 851 * Gem forced migration using the i915_ttm_migrate() op, is allowed even 852 * to regions that are not in the object's list of allowable placements. 853 */ 854 static int __i915_ttm_migrate(struct drm_i915_gem_object *obj, 855 struct intel_memory_region *mr, 856 unsigned int flags) 857 { 858 struct ttm_place requested; 859 struct ttm_placement placement; 860 int ret; 861 862 i915_ttm_place_from_region(mr, &requested, obj->bo_offset, 863 obj->base.size, flags); 864 placement.num_placement = 1; 865 placement.num_busy_placement = 1; 866 placement.placement = &requested; 867 placement.busy_placement = &requested; 868 869 ret = __i915_ttm_get_pages(obj, &placement); 870 if (ret) 871 return ret; 872 873 /* 874 * Reinitialize the region bindings. This is primarily 875 * required for objects where the new region is not in 876 * its allowable placements. 877 */ 878 if (obj->mm.region != mr) { 879 i915_gem_object_release_memory_region(obj); 880 i915_gem_object_init_memory_region(obj, mr); 881 } 882 883 return 0; 884 } 885 886 static int i915_ttm_migrate(struct drm_i915_gem_object *obj, 887 struct intel_memory_region *mr, 888 unsigned int flags) 889 { 890 return __i915_ttm_migrate(obj, mr, flags); 891 } 892 893 static void i915_ttm_put_pages(struct drm_i915_gem_object *obj, 894 struct sg_table *st) 895 { 896 /* 897 * We're currently not called from a shrinker, so put_pages() 898 * typically means the object is about to destroyed, or called 899 * from move_notify(). So just avoid doing much for now. 900 * If the object is not destroyed next, The TTM eviction logic 901 * and shrinkers will move it out if needed. 902 */ 903 904 if (obj->mm.rsgt) 905 i915_refct_sgt_put(fetch_and_zero(&obj->mm.rsgt)); 906 } 907 908 /** 909 * i915_ttm_adjust_lru - Adjust an object's position on relevant LRU lists. 910 * @obj: The object 911 */ 912 void i915_ttm_adjust_lru(struct drm_i915_gem_object *obj) 913 { 914 struct ttm_buffer_object *bo = i915_gem_to_ttm(obj); 915 struct i915_ttm_tt *i915_tt = 916 container_of(bo->ttm, typeof(*i915_tt), ttm); 917 bool shrinkable = 918 bo->ttm && i915_tt->filp && ttm_tt_is_populated(bo->ttm); 919 920 /* 921 * Don't manipulate the TTM LRUs while in TTM bo destruction. 922 * We're called through i915_ttm_delete_mem_notify(). 923 */ 924 if (!kref_read(&bo->kref)) 925 return; 926 927 /* 928 * We skip managing the shrinker LRU in set_pages() and just manage 929 * everything here. This does at least solve the issue with having 930 * temporary shmem mappings(like with evicted lmem) not being visible to 931 * the shrinker. Only our shmem objects are shrinkable, everything else 932 * we keep as unshrinkable. 933 * 934 * To make sure everything plays nice we keep an extra shrink pin in TTM 935 * if the underlying pages are not currently shrinkable. Once we release 936 * our pin, like when the pages are moved to shmem, the pages will then 937 * be added to the shrinker LRU, assuming the caller isn't also holding 938 * a pin. 939 * 940 * TODO: consider maybe also bumping the shrinker list here when we have 941 * already unpinned it, which should give us something more like an LRU. 942 * 943 * TODO: There is a small window of opportunity for this function to 944 * get called from eviction after we've dropped the last GEM refcount, 945 * but before the TTM deleted flag is set on the object. Avoid 946 * adjusting the shrinker list in such cases, since the object is 947 * not available to the shrinker anyway due to its zero refcount. 948 * To fix this properly we should move to a TTM shrinker LRU list for 949 * these objects. 950 */ 951 if (kref_get_unless_zero(&obj->base.refcount)) { 952 if (shrinkable != obj->mm.ttm_shrinkable) { 953 if (shrinkable) { 954 if (obj->mm.madv == I915_MADV_WILLNEED) 955 __i915_gem_object_make_shrinkable(obj); 956 else 957 __i915_gem_object_make_purgeable(obj); 958 } else { 959 i915_gem_object_make_unshrinkable(obj); 960 } 961 962 obj->mm.ttm_shrinkable = shrinkable; 963 } 964 i915_gem_object_put(obj); 965 } 966 967 /* 968 * Put on the correct LRU list depending on the MADV status 969 */ 970 spin_lock(&bo->bdev->lru_lock); 971 if (shrinkable) { 972 /* Try to keep shmem_tt from being considered for shrinking. */ 973 bo->priority = TTM_MAX_BO_PRIORITY - 1; 974 } else if (obj->mm.madv != I915_MADV_WILLNEED) { 975 bo->priority = I915_TTM_PRIO_PURGE; 976 } else if (!i915_gem_object_has_pages(obj)) { 977 bo->priority = I915_TTM_PRIO_NO_PAGES; 978 } else { 979 struct ttm_resource_manager *man = 980 ttm_manager_type(bo->bdev, bo->resource->mem_type); 981 982 /* 983 * If we need to place an LMEM resource which doesn't need CPU 984 * access then we should try not to victimize mappable objects 985 * first, since we likely end up stealing more of the mappable 986 * portion. And likewise when we try to find space for a mappble 987 * object, we know not to ever victimize objects that don't 988 * occupy any mappable pages. 989 */ 990 if (i915_ttm_cpu_maps_iomem(bo->resource) && 991 i915_ttm_buddy_man_visible_size(man) < man->size && 992 !(obj->flags & I915_BO_ALLOC_GPU_ONLY)) 993 bo->priority = I915_TTM_PRIO_NEEDS_CPU_ACCESS; 994 else 995 bo->priority = I915_TTM_PRIO_HAS_PAGES; 996 } 997 998 ttm_bo_move_to_lru_tail(bo); 999 spin_unlock(&bo->bdev->lru_lock); 1000 } 1001 1002 /* 1003 * TTM-backed gem object destruction requires some clarification. 1004 * Basically we have two possibilities here. We can either rely on the 1005 * i915 delayed destruction and put the TTM object when the object 1006 * is idle. This would be detected by TTM which would bypass the 1007 * TTM delayed destroy handling. The other approach is to put the TTM 1008 * object early and rely on the TTM destroyed handling, and then free 1009 * the leftover parts of the GEM object once TTM's destroyed list handling is 1010 * complete. For now, we rely on the latter for two reasons: 1011 * a) TTM can evict an object even when it's on the delayed destroy list, 1012 * which in theory allows for complete eviction. 1013 * b) There is work going on in TTM to allow freeing an object even when 1014 * it's not idle, and using the TTM destroyed list handling could help us 1015 * benefit from that. 1016 */ 1017 static void i915_ttm_delayed_free(struct drm_i915_gem_object *obj) 1018 { 1019 GEM_BUG_ON(!obj->ttm.created); 1020 1021 ttm_bo_put(i915_gem_to_ttm(obj)); 1022 } 1023 1024 static vm_fault_t vm_fault_ttm(struct vm_fault *vmf) 1025 { 1026 struct vm_area_struct *area = vmf->vma; 1027 struct ttm_buffer_object *bo = area->vm_private_data; 1028 struct drm_device *dev = bo->base.dev; 1029 struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); 1030 intel_wakeref_t wakeref = 0; 1031 vm_fault_t ret; 1032 int idx; 1033 1034 if (i915_ttm_is_ghost_object(bo)) 1035 return VM_FAULT_SIGBUS; 1036 1037 /* Sanity check that we allow writing into this object */ 1038 if (unlikely(i915_gem_object_is_readonly(obj) && 1039 area->vm_flags & VM_WRITE)) 1040 return VM_FAULT_SIGBUS; 1041 1042 ret = ttm_bo_vm_reserve(bo, vmf); 1043 if (ret) 1044 return ret; 1045 1046 if (obj->mm.madv != I915_MADV_WILLNEED) { 1047 dma_resv_unlock(bo->base.resv); 1048 return VM_FAULT_SIGBUS; 1049 } 1050 1051 if (!i915_ttm_resource_mappable(bo->resource)) { 1052 int err = -ENODEV; 1053 int i; 1054 1055 for (i = 0; i < obj->mm.n_placements; i++) { 1056 struct intel_memory_region *mr = obj->mm.placements[i]; 1057 unsigned int flags; 1058 1059 if (!mr->io_size && mr->type != INTEL_MEMORY_SYSTEM) 1060 continue; 1061 1062 flags = obj->flags; 1063 flags &= ~I915_BO_ALLOC_GPU_ONLY; 1064 err = __i915_ttm_migrate(obj, mr, flags); 1065 if (!err) 1066 break; 1067 } 1068 1069 if (err) { 1070 drm_dbg(dev, "Unable to make resource CPU accessible(err = %pe)\n", 1071 ERR_PTR(err)); 1072 dma_resv_unlock(bo->base.resv); 1073 ret = VM_FAULT_SIGBUS; 1074 goto out_rpm; 1075 } 1076 } 1077 1078 if (i915_ttm_cpu_maps_iomem(bo->resource)) 1079 wakeref = intel_runtime_pm_get(&to_i915(obj->base.dev)->runtime_pm); 1080 1081 if (drm_dev_enter(dev, &idx)) { 1082 ret = ttm_bo_vm_fault_reserved(vmf, vmf->vma->vm_page_prot, 1083 TTM_BO_VM_NUM_PREFAULT); 1084 drm_dev_exit(idx); 1085 } else { 1086 ret = ttm_bo_vm_dummy_page(vmf, vmf->vma->vm_page_prot); 1087 } 1088 1089 if (ret == VM_FAULT_RETRY && !(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) 1090 goto out_rpm; 1091 1092 /* 1093 * ttm_bo_vm_reserve() already has dma_resv_lock. 1094 * userfault_count is protected by dma_resv lock and rpm wakeref. 1095 */ 1096 if (ret == VM_FAULT_NOPAGE && wakeref && !obj->userfault_count) { 1097 obj->userfault_count = 1; 1098 spin_lock(&to_i915(obj->base.dev)->runtime_pm.lmem_userfault_lock); 1099 list_add(&obj->userfault_link, &to_i915(obj->base.dev)->runtime_pm.lmem_userfault_list); 1100 spin_unlock(&to_i915(obj->base.dev)->runtime_pm.lmem_userfault_lock); 1101 1102 GEM_WARN_ON(!i915_ttm_cpu_maps_iomem(bo->resource)); 1103 } 1104 1105 if (wakeref & CONFIG_DRM_I915_USERFAULT_AUTOSUSPEND) 1106 intel_wakeref_auto(&to_i915(obj->base.dev)->runtime_pm.userfault_wakeref, 1107 msecs_to_jiffies_timeout(CONFIG_DRM_I915_USERFAULT_AUTOSUSPEND)); 1108 1109 i915_ttm_adjust_lru(obj); 1110 1111 dma_resv_unlock(bo->base.resv); 1112 1113 out_rpm: 1114 if (wakeref) 1115 intel_runtime_pm_put(&to_i915(obj->base.dev)->runtime_pm, wakeref); 1116 1117 return ret; 1118 } 1119 1120 static int 1121 vm_access_ttm(struct vm_area_struct *area, unsigned long addr, 1122 void *buf, int len, int write) 1123 { 1124 struct drm_i915_gem_object *obj = 1125 i915_ttm_to_gem(area->vm_private_data); 1126 1127 if (i915_gem_object_is_readonly(obj) && write) 1128 return -EACCES; 1129 1130 return ttm_bo_vm_access(area, addr, buf, len, write); 1131 } 1132 1133 static void ttm_vm_open(struct vm_area_struct *vma) 1134 { 1135 struct drm_i915_gem_object *obj = 1136 i915_ttm_to_gem(vma->vm_private_data); 1137 1138 GEM_BUG_ON(i915_ttm_is_ghost_object(vma->vm_private_data)); 1139 i915_gem_object_get(obj); 1140 } 1141 1142 static void ttm_vm_close(struct vm_area_struct *vma) 1143 { 1144 struct drm_i915_gem_object *obj = 1145 i915_ttm_to_gem(vma->vm_private_data); 1146 1147 GEM_BUG_ON(i915_ttm_is_ghost_object(vma->vm_private_data)); 1148 i915_gem_object_put(obj); 1149 } 1150 1151 static const struct vm_operations_struct vm_ops_ttm = { 1152 .fault = vm_fault_ttm, 1153 .access = vm_access_ttm, 1154 .open = ttm_vm_open, 1155 .close = ttm_vm_close, 1156 }; 1157 1158 static u64 i915_ttm_mmap_offset(struct drm_i915_gem_object *obj) 1159 { 1160 /* The ttm_bo must be allocated with I915_BO_ALLOC_USER */ 1161 GEM_BUG_ON(!drm_mm_node_allocated(&obj->base.vma_node.vm_node)); 1162 1163 return drm_vma_node_offset_addr(&obj->base.vma_node); 1164 } 1165 1166 static void i915_ttm_unmap_virtual(struct drm_i915_gem_object *obj) 1167 { 1168 struct ttm_buffer_object *bo = i915_gem_to_ttm(obj); 1169 intel_wakeref_t wakeref = 0; 1170 1171 assert_object_held_shared(obj); 1172 1173 if (i915_ttm_cpu_maps_iomem(bo->resource)) { 1174 wakeref = intel_runtime_pm_get(&to_i915(obj->base.dev)->runtime_pm); 1175 1176 /* userfault_count is protected by obj lock and rpm wakeref. */ 1177 if (obj->userfault_count) { 1178 spin_lock(&to_i915(obj->base.dev)->runtime_pm.lmem_userfault_lock); 1179 list_del(&obj->userfault_link); 1180 spin_unlock(&to_i915(obj->base.dev)->runtime_pm.lmem_userfault_lock); 1181 obj->userfault_count = 0; 1182 } 1183 } 1184 1185 GEM_WARN_ON(obj->userfault_count); 1186 1187 ttm_bo_unmap_virtual(i915_gem_to_ttm(obj)); 1188 1189 if (wakeref) 1190 intel_runtime_pm_put(&to_i915(obj->base.dev)->runtime_pm, wakeref); 1191 } 1192 1193 static const struct drm_i915_gem_object_ops i915_gem_ttm_obj_ops = { 1194 .name = "i915_gem_object_ttm", 1195 .flags = I915_GEM_OBJECT_IS_SHRINKABLE | 1196 I915_GEM_OBJECT_SELF_MANAGED_SHRINK_LIST, 1197 1198 .get_pages = i915_ttm_get_pages, 1199 .put_pages = i915_ttm_put_pages, 1200 .truncate = i915_ttm_truncate, 1201 .shrink = i915_ttm_shrink, 1202 1203 .adjust_lru = i915_ttm_adjust_lru, 1204 .delayed_free = i915_ttm_delayed_free, 1205 .migrate = i915_ttm_migrate, 1206 1207 .mmap_offset = i915_ttm_mmap_offset, 1208 .unmap_virtual = i915_ttm_unmap_virtual, 1209 .mmap_ops = &vm_ops_ttm, 1210 }; 1211 1212 void i915_ttm_bo_destroy(struct ttm_buffer_object *bo) 1213 { 1214 struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo); 1215 1216 i915_gem_object_release_memory_region(obj); 1217 mutex_destroy(&obj->ttm.get_io_page.lock); 1218 1219 if (obj->ttm.created) { 1220 /* 1221 * We freely manage the shrinker LRU outide of the mm.pages life 1222 * cycle. As a result when destroying the object we should be 1223 * extra paranoid and ensure we remove it from the LRU, before 1224 * we free the object. 1225 * 1226 * Touching the ttm_shrinkable outside of the object lock here 1227 * should be safe now that the last GEM object ref was dropped. 1228 */ 1229 if (obj->mm.ttm_shrinkable) 1230 i915_gem_object_make_unshrinkable(obj); 1231 1232 i915_ttm_backup_free(obj); 1233 1234 /* This releases all gem object bindings to the backend. */ 1235 __i915_gem_free_object(obj); 1236 1237 call_rcu(&obj->rcu, __i915_gem_free_object_rcu); 1238 } else { 1239 __i915_gem_object_fini(obj); 1240 } 1241 } 1242 1243 /** 1244 * __i915_gem_ttm_object_init - Initialize a ttm-backed i915 gem object 1245 * @mem: The initial memory region for the object. 1246 * @obj: The gem object. 1247 * @size: Object size in bytes. 1248 * @flags: gem object flags. 1249 * 1250 * Return: 0 on success, negative error code on failure. 1251 */ 1252 int __i915_gem_ttm_object_init(struct intel_memory_region *mem, 1253 struct drm_i915_gem_object *obj, 1254 resource_size_t offset, 1255 resource_size_t size, 1256 resource_size_t page_size, 1257 unsigned int flags) 1258 { 1259 static struct lock_class_key lock_class; 1260 struct drm_i915_private *i915 = mem->i915; 1261 struct ttm_operation_ctx ctx = { 1262 .interruptible = true, 1263 .no_wait_gpu = false, 1264 }; 1265 enum ttm_bo_type bo_type; 1266 int ret; 1267 1268 drm_gem_private_object_init(&i915->drm, &obj->base, size); 1269 i915_gem_object_init(obj, &i915_gem_ttm_obj_ops, &lock_class, flags); 1270 1271 obj->bo_offset = offset; 1272 1273 /* Don't put on a region list until we're either locked or fully initialized. */ 1274 obj->mm.region = mem; 1275 INIT_LIST_HEAD(&obj->mm.region_link); 1276 1277 INIT_RADIX_TREE(&obj->ttm.get_io_page.radix, GFP_KERNEL | __GFP_NOWARN); 1278 mutex_init(&obj->ttm.get_io_page.lock); 1279 bo_type = (obj->flags & I915_BO_ALLOC_USER) ? ttm_bo_type_device : 1280 ttm_bo_type_kernel; 1281 1282 obj->base.vma_node.driver_private = i915_gem_to_ttm(obj); 1283 1284 /* Forcing the page size is kernel internal only */ 1285 GEM_BUG_ON(page_size && obj->mm.n_placements); 1286 1287 /* 1288 * Keep an extra shrink pin to prevent the object from being made 1289 * shrinkable too early. If the ttm_tt is ever allocated in shmem, we 1290 * drop the pin. The TTM backend manages the shrinker LRU itself, 1291 * outside of the normal mm.pages life cycle. 1292 */ 1293 i915_gem_object_make_unshrinkable(obj); 1294 1295 /* 1296 * If this function fails, it will call the destructor, but 1297 * our caller still owns the object. So no freeing in the 1298 * destructor until obj->ttm.created is true. 1299 * Similarly, in delayed_destroy, we can't call ttm_bo_put() 1300 * until successful initialization. 1301 */ 1302 ret = ttm_bo_init_reserved(&i915->bdev, i915_gem_to_ttm(obj), bo_type, 1303 &i915_sys_placement, page_size >> PAGE_SHIFT, 1304 &ctx, NULL, NULL, i915_ttm_bo_destroy); 1305 if (ret) 1306 return i915_ttm_err_to_gem(ret); 1307 1308 obj->ttm.created = true; 1309 i915_gem_object_release_memory_region(obj); 1310 i915_gem_object_init_memory_region(obj, mem); 1311 i915_ttm_adjust_domains_after_move(obj); 1312 i915_ttm_adjust_gem_after_move(obj); 1313 i915_gem_object_unlock(obj); 1314 1315 return 0; 1316 } 1317 1318 static const struct intel_memory_region_ops ttm_system_region_ops = { 1319 .init_object = __i915_gem_ttm_object_init, 1320 .release = intel_region_ttm_fini, 1321 }; 1322 1323 struct intel_memory_region * 1324 i915_gem_ttm_system_setup(struct drm_i915_private *i915, 1325 u16 type, u16 instance) 1326 { 1327 struct intel_memory_region *mr; 1328 1329 mr = intel_memory_region_create(i915, 0, 1330 totalram_pages() << PAGE_SHIFT, 1331 PAGE_SIZE, 0, 0, 1332 type, instance, 1333 &ttm_system_region_ops); 1334 if (IS_ERR(mr)) 1335 return mr; 1336 1337 intel_memory_region_set_name(mr, "system-ttm"); 1338 return mr; 1339 } 1340