1/* 2 * SPDX-License-Identifier: MIT 3 * 4 * Copyright �� 2014-2016 Intel Corporation 5 */ 6 7#include <drm/drm_cache.h> 8 9#include "gt/intel_gt.h" 10#include "gt/intel_tlb.h" 11 12#include "i915_drv.h" 13#include "i915_gem_object.h" 14#include "i915_scatterlist.h" 15#include "i915_gem_lmem.h" 16#include "i915_gem_mman.h" 17 18void __i915_gem_object_set_pages(struct drm_i915_gem_object *obj, 19 struct sg_table *pages) 20{ 21 struct drm_i915_private *i915 = to_i915(obj->base.dev); 22 unsigned long supported = RUNTIME_INFO(i915)->page_sizes; 23 bool shrinkable; 24 int i; 25 26 assert_object_held_shared(obj); 27 28 if (i915_gem_object_is_volatile(obj)) 29 obj->mm.madv = I915_MADV_DONTNEED; 30 31 /* Make the pages coherent with the GPU (flushing any swapin). */ 32 if (obj->cache_dirty) { 33 WARN_ON_ONCE(IS_DGFX(i915)); 34 obj->write_domain = 0; 35 if (i915_gem_object_has_struct_page(obj)) 36 drm_clflush_sg(pages); 37 obj->cache_dirty = false; 38 } 39 40 obj->mm.get_page.sg_pos = pages->sgl; 41 obj->mm.get_page.sg_idx = 0; 42 obj->mm.get_dma_page.sg_pos = pages->sgl; 43 obj->mm.get_dma_page.sg_idx = 0; 44 45 obj->mm.pages = pages; 46 47 obj->mm.page_sizes.phys = i915_sg_dma_sizes(pages->sgl); 48 GEM_BUG_ON(!obj->mm.page_sizes.phys); 49 50 /* 51 * Calculate the supported page-sizes which fit into the given 52 * sg_page_sizes. This will give us the page-sizes which we may be able 53 * to use opportunistically when later inserting into the GTT. For 54 * example if phys=2G, then in theory we should be able to use 1G, 2M, 55 * 64K or 4K pages, although in practice this will depend on a number of 56 * other factors. 57 */ 58 obj->mm.page_sizes.sg = 0; 59 for_each_set_bit(i, &supported, ilog2(I915_GTT_MAX_PAGE_SIZE) + 1) { 60 if (obj->mm.page_sizes.phys & ~0u << i) 61 obj->mm.page_sizes.sg |= BIT(i); 62 } 63 GEM_BUG_ON(!HAS_PAGE_SIZES(i915, obj->mm.page_sizes.sg)); 64 65 shrinkable = i915_gem_object_is_shrinkable(obj); 66 67 if (i915_gem_object_is_tiled(obj) && 68 i915->gem_quirks & GEM_QUIRK_PIN_SWIZZLED_PAGES) { 69 GEM_BUG_ON(i915_gem_object_has_tiling_quirk(obj)); 70 i915_gem_object_set_tiling_quirk(obj); 71 GEM_BUG_ON(!list_empty(&obj->mm.link)); 72 atomic_inc(&obj->mm.shrink_pin); 73 shrinkable = false; 74 } 75 76 if (shrinkable && !i915_gem_object_has_self_managed_shrink_list(obj)) { 77 struct list_head *list; 78 unsigned long flags; 79 80 assert_object_held(obj); 81 spin_lock_irqsave(&i915->mm.obj_lock, flags); 82 83 i915->mm.shrink_count++; 84 i915->mm.shrink_memory += obj->base.size; 85 86 if (obj->mm.madv != I915_MADV_WILLNEED) 87 list = &i915->mm.purge_list; 88 else 89 list = &i915->mm.shrink_list; 90 list_add_tail(&obj->mm.link, list); 91 92 atomic_set(&obj->mm.shrink_pin, 0); 93 spin_unlock_irqrestore(&i915->mm.obj_lock, flags); 94 } 95} 96 97int ____i915_gem_object_get_pages(struct drm_i915_gem_object *obj) 98{ 99 struct drm_i915_private *i915 = to_i915(obj->base.dev); 100 int err; 101 102 assert_object_held_shared(obj); 103 104 if (unlikely(obj->mm.madv != I915_MADV_WILLNEED)) { 105 drm_dbg(&i915->drm, 106 "Attempting to obtain a purgeable object\n"); 107 return -EFAULT; 108 } 109 110 err = obj->ops->get_pages(obj); 111 GEM_BUG_ON(!err && !i915_gem_object_has_pages(obj)); 112 113 return err; 114} 115 116/* Ensure that the associated pages are gathered from the backing storage 117 * and pinned into our object. i915_gem_object_pin_pages() may be called 118 * multiple times before they are released by a single call to 119 * i915_gem_object_unpin_pages() - once the pages are no longer referenced 120 * either as a result of memory pressure (reaping pages under the shrinker) 121 * or as the object is itself released. 122 */ 123int __i915_gem_object_get_pages(struct drm_i915_gem_object *obj) 124{ 125 int err; 126 127 assert_object_held(obj); 128 129 assert_object_held_shared(obj); 130 131 if (unlikely(!i915_gem_object_has_pages(obj))) { 132 GEM_BUG_ON(i915_gem_object_has_pinned_pages(obj)); 133 134 err = ____i915_gem_object_get_pages(obj); 135 if (err) 136 return err; 137 138 smp_mb__before_atomic(); 139 } 140 atomic_inc(&obj->mm.pages_pin_count); 141 142 return 0; 143} 144 145int i915_gem_object_pin_pages_unlocked(struct drm_i915_gem_object *obj) 146{ 147 struct i915_gem_ww_ctx ww; 148 int err; 149 150 i915_gem_ww_ctx_init(&ww, true); 151retry: 152 err = i915_gem_object_lock(obj, &ww); 153 if (!err) 154 err = i915_gem_object_pin_pages(obj); 155 156 if (err == -EDEADLK) { 157 err = i915_gem_ww_ctx_backoff(&ww); 158 if (!err) 159 goto retry; 160 } 161 i915_gem_ww_ctx_fini(&ww); 162 return err; 163} 164 165/* Immediately discard the backing storage */ 166int i915_gem_object_truncate(struct drm_i915_gem_object *obj) 167{ 168 if (obj->ops->truncate) 169 return obj->ops->truncate(obj); 170 171 return 0; 172} 173 174static void __i915_gem_object_reset_page_iter(struct drm_i915_gem_object *obj) 175{ 176 struct radix_tree_iter iter; 177 void __rcu **slot; 178 179 rcu_read_lock(); 180 radix_tree_for_each_slot(slot, &obj->mm.get_page.radix, &iter, 0) 181 radix_tree_delete(&obj->mm.get_page.radix, iter.index); 182 radix_tree_for_each_slot(slot, &obj->mm.get_dma_page.radix, &iter, 0) 183 radix_tree_delete(&obj->mm.get_dma_page.radix, iter.index); 184 rcu_read_unlock(); 185} 186 187static void unmap_object(struct drm_i915_gem_object *obj, void *ptr) 188{ 189 if (is_vmalloc_addr(ptr)) 190 vunmap(ptr); 191} 192 193static void flush_tlb_invalidate(struct drm_i915_gem_object *obj) 194{ 195 struct drm_i915_private *i915 = to_i915(obj->base.dev); 196 struct intel_gt *gt; 197 int id; 198 199 for_each_gt(gt, i915, id) { 200 if (!obj->mm.tlb[id]) 201 continue; 202 203 intel_gt_invalidate_tlb_full(gt, obj->mm.tlb[id]); 204 obj->mm.tlb[id] = 0; 205 } 206} 207 208struct sg_table * 209__i915_gem_object_unset_pages(struct drm_i915_gem_object *obj) 210{ 211 struct sg_table *pages; 212 213 assert_object_held_shared(obj); 214 215 pages = fetch_and_zero(&obj->mm.pages); 216 if (IS_ERR_OR_NULL(pages)) 217 return pages; 218 219 if (i915_gem_object_is_volatile(obj)) 220 obj->mm.madv = I915_MADV_WILLNEED; 221 222 if (!i915_gem_object_has_self_managed_shrink_list(obj)) 223 i915_gem_object_make_unshrinkable(obj); 224 225 if (obj->mm.mapping) { 226 unmap_object(obj, page_mask_bits(obj->mm.mapping)); 227 obj->mm.mapping = NULL; 228 } 229 230 __i915_gem_object_reset_page_iter(obj); 231 obj->mm.page_sizes.phys = obj->mm.page_sizes.sg = 0; 232 233 flush_tlb_invalidate(obj); 234 235 return pages; 236} 237 238int __i915_gem_object_put_pages(struct drm_i915_gem_object *obj) 239{ 240 struct sg_table *pages; 241 242 if (i915_gem_object_has_pinned_pages(obj)) 243 return -EBUSY; 244 245 /* May be called by shrinker from within get_pages() (on another bo) */ 246 assert_object_held_shared(obj); 247 248 i915_gem_object_release_mmap_offset(obj); 249 250 /* 251 * ->put_pages might need to allocate memory for the bit17 swizzle 252 * array, hence protect them from being reaped by removing them from gtt 253 * lists early. 254 */ 255 pages = __i915_gem_object_unset_pages(obj); 256 257 /* 258 * XXX Temporary hijinx to avoid updating all backends to handle 259 * NULL pages. In the future, when we have more asynchronous 260 * get_pages backends we should be better able to handle the 261 * cancellation of the async task in a more uniform manner. 262 */ 263 if (!IS_ERR_OR_NULL(pages)) 264 obj->ops->put_pages(obj, pages); 265 266 return 0; 267} 268 269/* The 'mapping' part of i915_gem_object_pin_map() below */ 270static void *i915_gem_object_map_page(struct drm_i915_gem_object *obj, 271 enum i915_map_type type) 272{ 273 unsigned long n_pages = obj->base.size >> PAGE_SHIFT, i; 274 struct page *stack[32], **pages = stack, *page; 275 struct sgt_iter iter; 276 pgprot_t pgprot; 277 void *vaddr; 278 279 switch (type) { 280 default: 281 MISSING_CASE(type); 282 fallthrough; /* to use PAGE_KERNEL anyway */ 283 case I915_MAP_WB: 284 /* 285 * On 32b, highmem using a finite set of indirect PTE (i.e. 286 * vmap) to provide virtual mappings of the high pages. 287 * As these are finite, map_new_virtual() must wait for some 288 * other kmap() to finish when it runs out. If we map a large 289 * number of objects, there is no method for it to tell us 290 * to release the mappings, and we deadlock. 291 * 292 * However, if we make an explicit vmap of the page, that 293 * uses a larger vmalloc arena, and also has the ability 294 * to tell us to release unwanted mappings. Most importantly, 295 * it will fail and propagate an error instead of waiting 296 * forever. 297 * 298 * So if the page is beyond the 32b boundary, make an explicit 299 * vmap. 300 */ 301 if (n_pages == 1 && !PageHighMem(sg_page(obj->mm.pages->sgl))) 302 return page_address(sg_page(obj->mm.pages->sgl)); 303 pgprot = PAGE_KERNEL; 304 break; 305 case I915_MAP_WC: 306 pgprot = pgprot_writecombine(PAGE_KERNEL_IO); 307 break; 308 } 309 310 if (n_pages > ARRAY_SIZE(stack)) { 311 /* Too big for stack -- allocate temporary array instead */ 312 pages = kvmalloc_array(n_pages, sizeof(*pages), GFP_KERNEL); 313 if (!pages) 314 return ERR_PTR(-ENOMEM); 315 } 316 317 i = 0; 318 for_each_sgt_page(page, iter, obj->mm.pages) 319 pages[i++] = page; 320 vaddr = vmap(pages, n_pages, 0, pgprot); 321 if (pages != stack) 322 kvfree(pages); 323 324 return vaddr ?: ERR_PTR(-ENOMEM); 325} 326 327static void *i915_gem_object_map_pfn(struct drm_i915_gem_object *obj, 328 enum i915_map_type type) 329{ 330 resource_size_t iomap = obj->mm.region->iomap.base - 331 obj->mm.region->region.start; 332 unsigned long n_pfn = obj->base.size >> PAGE_SHIFT; 333 unsigned long stack[32], *pfns = stack, i; 334 struct sgt_iter iter; 335 dma_addr_t addr; 336 void *vaddr; 337 338 GEM_BUG_ON(type != I915_MAP_WC); 339 340 if (n_pfn > ARRAY_SIZE(stack)) { 341 /* Too big for stack -- allocate temporary array instead */ 342 pfns = kvmalloc_array(n_pfn, sizeof(*pfns), GFP_KERNEL); 343 if (!pfns) 344 return ERR_PTR(-ENOMEM); 345 } 346 347 i = 0; 348 for_each_sgt_daddr(addr, iter, obj->mm.pages) 349 pfns[i++] = (iomap + addr) >> PAGE_SHIFT; 350 vaddr = vmap_pfn(pfns, n_pfn, pgprot_writecombine(PAGE_KERNEL_IO)); 351 if (pfns != stack) 352 kvfree(pfns); 353 354 return vaddr ?: ERR_PTR(-ENOMEM); 355} 356 357/* get, pin, and map the pages of the object into kernel space */ 358void *i915_gem_object_pin_map(struct drm_i915_gem_object *obj, 359 enum i915_map_type type) 360{ 361 enum i915_map_type has_type; 362 bool pinned; 363 void *ptr; 364 int err; 365 366 if (!i915_gem_object_has_struct_page(obj) && 367 !i915_gem_object_has_iomem(obj)) 368 return ERR_PTR(-ENXIO); 369 370 if (WARN_ON_ONCE(obj->flags & I915_BO_ALLOC_GPU_ONLY)) 371 return ERR_PTR(-EINVAL); 372 373 assert_object_held(obj); 374 375 pinned = !(type & I915_MAP_OVERRIDE); 376 type &= ~I915_MAP_OVERRIDE; 377 378 if (!atomic_inc_not_zero(&obj->mm.pages_pin_count)) { 379 if (unlikely(!i915_gem_object_has_pages(obj))) { 380 GEM_BUG_ON(i915_gem_object_has_pinned_pages(obj)); 381 382 err = ____i915_gem_object_get_pages(obj); 383 if (err) 384 return ERR_PTR(err); 385 386 smp_mb__before_atomic(); 387 } 388 atomic_inc(&obj->mm.pages_pin_count); 389 pinned = false; 390 } 391 GEM_BUG_ON(!i915_gem_object_has_pages(obj)); 392 393 /* 394 * For discrete our CPU mappings needs to be consistent in order to 395 * function correctly on !x86. When mapping things through TTM, we use 396 * the same rules to determine the caching type. 397 * 398 * The caching rules, starting from DG1: 399 * 400 * - If the object can be placed in device local-memory, then the 401 * pages should be allocated and mapped as write-combined only. 402 * 403 * - Everything else is always allocated and mapped as write-back, 404 * with the guarantee that everything is also coherent with the 405 * GPU. 406 * 407 * Internal users of lmem are already expected to get this right, so no 408 * fudging needed there. 409 */ 410 if (i915_gem_object_placement_possible(obj, INTEL_MEMORY_LOCAL)) { 411 if (type != I915_MAP_WC && !obj->mm.n_placements) { 412 ptr = ERR_PTR(-ENODEV); 413 goto err_unpin; 414 } 415 416 type = I915_MAP_WC; 417 } else if (IS_DGFX(to_i915(obj->base.dev))) { 418 type = I915_MAP_WB; 419 } 420 421 ptr = page_unpack_bits(obj->mm.mapping, &has_type); 422 if (ptr && has_type != type) { 423 if (pinned) { 424 ptr = ERR_PTR(-EBUSY); 425 goto err_unpin; 426 } 427 428 unmap_object(obj, ptr); 429 430 ptr = obj->mm.mapping = NULL; 431 } 432 433 if (!ptr) { 434 err = i915_gem_object_wait_moving_fence(obj, true); 435 if (err) { 436 ptr = ERR_PTR(err); 437 goto err_unpin; 438 } 439 440 if (GEM_WARN_ON(type == I915_MAP_WC && !pat_enabled())) 441 ptr = ERR_PTR(-ENODEV); 442 else if (i915_gem_object_has_struct_page(obj)) 443 ptr = i915_gem_object_map_page(obj, type); 444 else 445 ptr = i915_gem_object_map_pfn(obj, type); 446 if (IS_ERR(ptr)) 447 goto err_unpin; 448 449 obj->mm.mapping = page_pack_bits(ptr, type); 450 } 451 452 return ptr; 453 454err_unpin: 455 atomic_dec(&obj->mm.pages_pin_count); 456 return ptr; 457} 458 459void *i915_gem_object_pin_map_unlocked(struct drm_i915_gem_object *obj, 460 enum i915_map_type type) 461{ 462 void *ret; 463 464 i915_gem_object_lock(obj, NULL); 465 ret = i915_gem_object_pin_map(obj, type); 466 i915_gem_object_unlock(obj); 467 468 return ret; 469} 470 471void __i915_gem_object_flush_map(struct drm_i915_gem_object *obj, 472 unsigned long offset, 473 unsigned long size) 474{ 475 enum i915_map_type has_type; 476 void *ptr; 477 478 GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj)); 479 GEM_BUG_ON(range_overflows_t(typeof(obj->base.size), 480 offset, size, obj->base.size)); 481 482 wmb(); /* let all previous writes be visible to coherent partners */ 483 obj->mm.dirty = true; 484 485 if (obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_WRITE) 486 return; 487 488 ptr = page_unpack_bits(obj->mm.mapping, &has_type); 489 if (has_type == I915_MAP_WC) 490 return; 491 492 drm_clflush_virt_range(ptr + offset, size); 493 if (size == obj->base.size) { 494 obj->write_domain &= ~I915_GEM_DOMAIN_CPU; 495 obj->cache_dirty = false; 496 } 497} 498 499void __i915_gem_object_release_map(struct drm_i915_gem_object *obj) 500{ 501 GEM_BUG_ON(!obj->mm.mapping); 502 503 /* 504 * We allow removing the mapping from underneath pinned pages! 505 * 506 * Furthermore, since this is an unsafe operation reserved only 507 * for construction time manipulation, we ignore locking prudence. 508 */ 509 unmap_object(obj, page_mask_bits(fetch_and_zero(&obj->mm.mapping))); 510 511 i915_gem_object_unpin_map(obj); 512} 513 514struct scatterlist * 515__i915_gem_object_page_iter_get_sg(struct drm_i915_gem_object *obj, 516 struct i915_gem_object_page_iter *iter, 517 pgoff_t n, 518 unsigned int *offset) 519 520{ 521 const bool dma = iter == &obj->mm.get_dma_page || 522 iter == &obj->ttm.get_io_page; 523 unsigned int idx, count; 524 struct scatterlist *sg; 525 526 might_sleep(); 527 GEM_BUG_ON(n >= obj->base.size >> PAGE_SHIFT); 528 if (!i915_gem_object_has_pinned_pages(obj)) 529 assert_object_held(obj); 530 531 /* As we iterate forward through the sg, we record each entry in a 532 * radixtree for quick repeated (backwards) lookups. If we have seen 533 * this index previously, we will have an entry for it. 534 * 535 * Initial lookup is O(N), but this is amortized to O(1) for 536 * sequential page access (where each new request is consecutive 537 * to the previous one). Repeated lookups are O(lg(obj->base.size)), 538 * i.e. O(1) with a large constant! 539 */ 540 if (n < READ_ONCE(iter->sg_idx)) 541 goto lookup; 542 543 mutex_lock(&iter->lock); 544 545 /* We prefer to reuse the last sg so that repeated lookup of this 546 * (or the subsequent) sg are fast - comparing against the last 547 * sg is faster than going through the radixtree. 548 */ 549 550 sg = iter->sg_pos; 551 idx = iter->sg_idx; 552 count = dma ? __sg_dma_page_count(sg) : __sg_page_count(sg); 553 554 while (idx + count <= n) { 555 void *entry; 556 unsigned long i; 557 int ret; 558 559 /* If we cannot allocate and insert this entry, or the 560 * individual pages from this range, cancel updating the 561 * sg_idx so that on this lookup we are forced to linearly 562 * scan onwards, but on future lookups we will try the 563 * insertion again (in which case we need to be careful of 564 * the error return reporting that we have already inserted 565 * this index). 566 */ 567 ret = radix_tree_insert(&iter->radix, idx, sg); 568 if (ret && ret != -EEXIST) 569 goto scan; 570 571 entry = xa_mk_value(idx); 572 for (i = 1; i < count; i++) { 573 ret = radix_tree_insert(&iter->radix, idx + i, entry); 574 if (ret && ret != -EEXIST) 575 goto scan; 576 } 577 578 idx += count; 579 sg = ____sg_next(sg); 580 count = dma ? __sg_dma_page_count(sg) : __sg_page_count(sg); 581 } 582 583scan: 584 iter->sg_pos = sg; 585 iter->sg_idx = idx; 586 587 mutex_unlock(&iter->lock); 588 589 if (unlikely(n < idx)) /* insertion completed by another thread */ 590 goto lookup; 591 592 /* In case we failed to insert the entry into the radixtree, we need 593 * to look beyond the current sg. 594 */ 595 while (idx + count <= n) { 596 idx += count; 597 sg = ____sg_next(sg); 598 count = dma ? __sg_dma_page_count(sg) : __sg_page_count(sg); 599 } 600 601 *offset = n - idx; 602 return sg; 603 604lookup: 605 rcu_read_lock(); 606 607 sg = radix_tree_lookup(&iter->radix, n); 608 GEM_BUG_ON(!sg); 609 610 /* If this index is in the middle of multi-page sg entry, 611 * the radix tree will contain a value entry that points 612 * to the start of that range. We will return the pointer to 613 * the base page and the offset of this page within the 614 * sg entry's range. 615 */ 616 *offset = 0; 617 if (unlikely(xa_is_value(sg))) { 618 unsigned long base = xa_to_value(sg); 619 620 sg = radix_tree_lookup(&iter->radix, base); 621 GEM_BUG_ON(!sg); 622 623 *offset = n - base; 624 } 625 626 rcu_read_unlock(); 627 628 return sg; 629} 630 631struct page * 632__i915_gem_object_get_page(struct drm_i915_gem_object *obj, pgoff_t n) 633{ 634 struct scatterlist *sg; 635 unsigned int offset; 636 637 GEM_BUG_ON(!i915_gem_object_has_struct_page(obj)); 638 639 sg = i915_gem_object_get_sg(obj, n, &offset); 640 return nth_page(sg_page(sg), offset); 641} 642 643/* Like i915_gem_object_get_page(), but mark the returned page dirty */ 644struct page * 645__i915_gem_object_get_dirty_page(struct drm_i915_gem_object *obj, pgoff_t n) 646{ 647 struct page *page; 648 649 page = i915_gem_object_get_page(obj, n); 650 if (!obj->mm.dirty) 651 set_page_dirty(page); 652 653 return page; 654} 655 656dma_addr_t 657__i915_gem_object_get_dma_address_len(struct drm_i915_gem_object *obj, 658 pgoff_t n, unsigned int *len) 659{ 660 struct scatterlist *sg; 661 unsigned int offset; 662 663 sg = i915_gem_object_get_sg_dma(obj, n, &offset); 664 665 if (len) 666 *len = sg_dma_len(sg) - (offset << PAGE_SHIFT); 667 668 return sg_dma_address(sg) + (offset << PAGE_SHIFT); 669} 670 671dma_addr_t 672__i915_gem_object_get_dma_address(struct drm_i915_gem_object *obj, pgoff_t n) 673{ 674 return i915_gem_object_get_dma_address_len(obj, n, NULL); 675} 676