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_placement.h>
9#include <drm/ttm/ttm_tt.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 */
49struct 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
58static const struct ttm_place sys_placement_flags = {
59 .fpfn = 0,
60 .lpfn = 0,
61 .mem_type = I915_PL_SYSTEM,
62 .flags = 0,
63};
64
65static struct ttm_placement i915_sys_placement = {
66 .num_placement = 1,
67 .placement = &sys_placement_flags,
68};
69
70/**
71 * i915_ttm_sys_placement - Return the struct ttm_placement to be
72 * used for an object in system memory.
73 *
74 * Rather than making the struct extern, use this
75 * function.
76 *
77 * Return: A pointer to a static variable for sys placement.
78 */
79struct ttm_placement *i915_ttm_sys_placement(void)
80{
81 return &i915_sys_placement;
82}
83
84static int i915_ttm_err_to_gem(int err)
85{
86 /* Fastpath */
87 if (likely(!err))
88 return 0;
89
90 switch (err) {
91 case -EBUSY:
92 /*
93 * TTM likes to convert -EDEADLK to -EBUSY, and wants us to
94 * restart the operation, since we don't record the contending
95 * lock. We use -EAGAIN to restart.
96 */
97 return -EAGAIN;
98 case -ENOSPC:
99 /*
100 * Memory type / region is full, and we can't evict.
101 * Except possibly system, that returns -ENOMEM;
102 */
103 return -ENXIO;
104 default:
105 break;
106 }
107
108 return err;
109}
110
111static enum ttm_caching
112i915_ttm_select_tt_caching(const struct drm_i915_gem_object *obj)
113{
114 /*
115 * Objects only allowed in system get cached cpu-mappings, or when
116 * evicting lmem-only buffers to system for swapping. Other objects get
117 * WC mapping for now. Even if in system.
118 */
119 if (obj->mm.n_placements <= 1)
120 return ttm_cached;
121
122 return ttm_write_combined;
123}
124
125static void
126i915_ttm_place_from_region(const struct intel_memory_region *mr,
127 struct ttm_place *place,
128 resource_size_t offset,
129 resource_size_t size,
130 unsigned int flags)
131{
132 memset(s: place, c: 0, n: sizeof(*place));
133 place->mem_type = intel_region_to_ttm_type(mem: mr);
134
135 if (mr->type == INTEL_MEMORY_SYSTEM)
136 return;
137
138 if (flags & I915_BO_ALLOC_CONTIGUOUS)
139 place->flags |= TTM_PL_FLAG_CONTIGUOUS;
140 if (offset != I915_BO_INVALID_OFFSET) {
141 WARN_ON(overflows_type(offset >> PAGE_SHIFT, place->fpfn));
142 place->fpfn = offset >> PAGE_SHIFT;
143 WARN_ON(overflows_type(place->fpfn + (size >> PAGE_SHIFT), place->lpfn));
144 place->lpfn = place->fpfn + (size >> PAGE_SHIFT);
145 } else if (resource_size(res: &mr->io) && resource_size(res: &mr->io) < mr->total) {
146 if (flags & I915_BO_ALLOC_GPU_ONLY) {
147 place->flags |= TTM_PL_FLAG_TOPDOWN;
148 } else {
149 place->fpfn = 0;
150 WARN_ON(overflows_type(resource_size(&mr->io) >> PAGE_SHIFT, place->lpfn));
151 place->lpfn = resource_size(res: &mr->io) >> PAGE_SHIFT;
152 }
153 }
154}
155
156static void
157i915_ttm_placement_from_obj(const struct drm_i915_gem_object *obj,
158 struct ttm_place *places,
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 i915_ttm_place_from_region(mr: num_allowed ? obj->mm.placements[0] :
166 obj->mm.region, place: &places[0], offset: obj->bo_offset,
167 size: obj->base.size, flags);
168
169 /* Cache this on object? */
170 for (i = 0; i < num_allowed; ++i) {
171 i915_ttm_place_from_region(mr: obj->mm.placements[i],
172 place: &places[i + 1], offset: obj->bo_offset,
173 size: obj->base.size, flags);
174 places[i + 1].flags |= TTM_PL_FLAG_FALLBACK;
175 }
176
177 placement->num_placement = num_allowed + 1;
178 placement->placement = places;
179}
180
181static int i915_ttm_tt_shmem_populate(struct ttm_device *bdev,
182 struct ttm_tt *ttm,
183 struct ttm_operation_ctx *ctx)
184{
185 struct drm_i915_private *i915 = container_of(bdev, typeof(*i915), bdev);
186 struct intel_memory_region *mr = i915->mm.regions[INTEL_MEMORY_SYSTEM];
187 struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm);
188 const unsigned int max_segment = i915_sg_segment_size(dev: i915->drm.dev);
189 const size_t size = (size_t)ttm->num_pages << PAGE_SHIFT;
190 struct file *filp = i915_tt->filp;
191 struct sgt_iter sgt_iter;
192 struct sg_table *st;
193 struct page *page;
194 unsigned long i;
195 int err;
196
197 if (!filp) {
198 struct address_space *mapping;
199 gfp_t mask;
200
201 filp = shmem_file_setup(name: "i915-shmem-tt", size, VM_NORESERVE);
202 if (IS_ERR(ptr: filp))
203 return PTR_ERR(ptr: filp);
204
205 mask = GFP_HIGHUSER | __GFP_RECLAIMABLE;
206
207 mapping = filp->f_mapping;
208 mapping_set_gfp_mask(m: mapping, mask);
209 GEM_BUG_ON(!(mapping_gfp_mask(mapping) & __GFP_RECLAIM));
210
211 i915_tt->filp = filp;
212 }
213
214 st = &i915_tt->cached_rsgt.table;
215 err = shmem_sg_alloc_table(i915, st, size, mr, mapping: filp->f_mapping,
216 max_segment);
217 if (err)
218 return err;
219
220 err = dma_map_sgtable(dev: i915_tt->dev, sgt: st, dir: DMA_BIDIRECTIONAL,
221 DMA_ATTR_SKIP_CPU_SYNC);
222 if (err)
223 goto err_free_st;
224
225 i = 0;
226 for_each_sgt_page(page, sgt_iter, st)
227 ttm->pages[i++] = page;
228
229 if (ttm->page_flags & TTM_TT_FLAG_SWAPPED)
230 ttm->page_flags &= ~TTM_TT_FLAG_SWAPPED;
231
232 return 0;
233
234err_free_st:
235 shmem_sg_free_table(st, mapping: filp->f_mapping, dirty: false, backup: false);
236
237 return err;
238}
239
240static void i915_ttm_tt_shmem_unpopulate(struct ttm_tt *ttm)
241{
242 struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm);
243 bool backup = ttm->page_flags & TTM_TT_FLAG_SWAPPED;
244 struct sg_table *st = &i915_tt->cached_rsgt.table;
245
246 shmem_sg_free_table(st, mapping: file_inode(f: i915_tt->filp)->i_mapping,
247 dirty: backup, backup);
248}
249
250static void i915_ttm_tt_release(struct kref *ref)
251{
252 struct i915_ttm_tt *i915_tt =
253 container_of(ref, typeof(*i915_tt), cached_rsgt.kref);
254 struct sg_table *st = &i915_tt->cached_rsgt.table;
255
256 GEM_WARN_ON(st->sgl);
257
258 kfree(objp: i915_tt);
259}
260
261static const struct i915_refct_sgt_ops tt_rsgt_ops = {
262 .release = i915_ttm_tt_release
263};
264
265static struct ttm_tt *i915_ttm_tt_create(struct ttm_buffer_object *bo,
266 uint32_t page_flags)
267{
268 struct drm_i915_private *i915 = container_of(bo->bdev, typeof(*i915),
269 bdev);
270 struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
271 unsigned long ccs_pages = 0;
272 enum ttm_caching caching;
273 struct i915_ttm_tt *i915_tt;
274 int ret;
275
276 if (i915_ttm_is_ghost_object(bo))
277 return NULL;
278
279 i915_tt = kzalloc(sizeof(*i915_tt), GFP_KERNEL);
280 if (!i915_tt)
281 return NULL;
282
283 if (obj->flags & I915_BO_ALLOC_CPU_CLEAR && (!bo->resource ||
284 ttm_manager_type(bdev: bo->bdev, mem_type: bo->resource->mem_type)->use_tt))
285 page_flags |= TTM_TT_FLAG_ZERO_ALLOC;
286
287 caching = i915_ttm_select_tt_caching(obj);
288 if (i915_gem_object_is_shrinkable(obj) && caching == ttm_cached) {
289 page_flags |= TTM_TT_FLAG_EXTERNAL |
290 TTM_TT_FLAG_EXTERNAL_MAPPABLE;
291 i915_tt->is_shmem = true;
292 }
293
294 if (i915_gem_object_needs_ccs_pages(obj))
295 ccs_pages = DIV_ROUND_UP(DIV_ROUND_UP(bo->base.size,
296 NUM_BYTES_PER_CCS_BYTE),
297 PAGE_SIZE);
298
299 ret = ttm_tt_init(ttm: &i915_tt->ttm, bo, page_flags, caching, extra_pages: ccs_pages);
300 if (ret)
301 goto err_free;
302
303 __i915_refct_sgt_init(rsgt: &i915_tt->cached_rsgt, size: bo->base.size,
304 ops: &tt_rsgt_ops);
305
306 i915_tt->dev = obj->base.dev->dev;
307
308 return &i915_tt->ttm;
309
310err_free:
311 kfree(objp: i915_tt);
312 return NULL;
313}
314
315static int i915_ttm_tt_populate(struct ttm_device *bdev,
316 struct ttm_tt *ttm,
317 struct ttm_operation_ctx *ctx)
318{
319 struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm);
320
321 if (i915_tt->is_shmem)
322 return i915_ttm_tt_shmem_populate(bdev, ttm, ctx);
323
324 return ttm_pool_alloc(pool: &bdev->pool, tt: ttm, ctx);
325}
326
327static void i915_ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm)
328{
329 struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm);
330 struct sg_table *st = &i915_tt->cached_rsgt.table;
331
332 if (st->sgl)
333 dma_unmap_sgtable(dev: i915_tt->dev, sgt: st, dir: DMA_BIDIRECTIONAL, attrs: 0);
334
335 if (i915_tt->is_shmem) {
336 i915_ttm_tt_shmem_unpopulate(ttm);
337 } else {
338 sg_free_table(st);
339 ttm_pool_free(pool: &bdev->pool, tt: ttm);
340 }
341}
342
343static void i915_ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *ttm)
344{
345 struct i915_ttm_tt *i915_tt = container_of(ttm, typeof(*i915_tt), ttm);
346
347 if (i915_tt->filp)
348 fput(i915_tt->filp);
349
350 ttm_tt_fini(ttm);
351 i915_refct_sgt_put(rsgt: &i915_tt->cached_rsgt);
352}
353
354static bool i915_ttm_eviction_valuable(struct ttm_buffer_object *bo,
355 const struct ttm_place *place)
356{
357 struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
358
359 if (i915_ttm_is_ghost_object(bo))
360 return false;
361
362 /*
363 * EXTERNAL objects should never be swapped out by TTM, instead we need
364 * to handle that ourselves. TTM will already skip such objects for us,
365 * but we would like to avoid grabbing locks for no good reason.
366 */
367 if (bo->ttm && bo->ttm->page_flags & TTM_TT_FLAG_EXTERNAL)
368 return false;
369
370 /* Will do for now. Our pinned objects are still on TTM's LRU lists */
371 if (!i915_gem_object_evictable(obj))
372 return false;
373
374 return ttm_bo_eviction_valuable(bo, place);
375}
376
377static void i915_ttm_evict_flags(struct ttm_buffer_object *bo,
378 struct ttm_placement *placement)
379{
380 *placement = i915_sys_placement;
381}
382
383/**
384 * i915_ttm_free_cached_io_rsgt - Free object cached LMEM information
385 * @obj: The GEM object
386 * This function frees any LMEM-related information that is cached on
387 * the object. For example the radix tree for fast page lookup and the
388 * cached refcounted sg-table
389 */
390void i915_ttm_free_cached_io_rsgt(struct drm_i915_gem_object *obj)
391{
392 struct radix_tree_iter iter;
393 void __rcu **slot;
394
395 if (!obj->ttm.cached_io_rsgt)
396 return;
397
398 rcu_read_lock();
399 radix_tree_for_each_slot(slot, &obj->ttm.get_io_page.radix, &iter, 0)
400 radix_tree_delete(&obj->ttm.get_io_page.radix, iter.index);
401 rcu_read_unlock();
402
403 i915_refct_sgt_put(rsgt: obj->ttm.cached_io_rsgt);
404 obj->ttm.cached_io_rsgt = NULL;
405}
406
407/**
408 * i915_ttm_purge - Clear an object of its memory
409 * @obj: The object
410 *
411 * This function is called to clear an object of it's memory when it is
412 * marked as not needed anymore.
413 *
414 * Return: 0 on success, negative error code on failure.
415 */
416int i915_ttm_purge(struct drm_i915_gem_object *obj)
417{
418 struct ttm_buffer_object *bo = i915_gem_to_ttm(obj);
419 struct i915_ttm_tt *i915_tt =
420 container_of(bo->ttm, typeof(*i915_tt), ttm);
421 struct ttm_operation_ctx ctx = {
422 .interruptible = true,
423 .no_wait_gpu = false,
424 };
425 struct ttm_placement place = {};
426 int ret;
427
428 if (obj->mm.madv == __I915_MADV_PURGED)
429 return 0;
430
431 ret = ttm_bo_validate(bo, placement: &place, ctx: &ctx);
432 if (ret)
433 return ret;
434
435 if (bo->ttm && i915_tt->filp) {
436 /*
437 * The below fput(which eventually calls shmem_truncate) might
438 * be delayed by worker, so when directly called to purge the
439 * pages(like by the shrinker) we should try to be more
440 * aggressive and release the pages immediately.
441 */
442 shmem_truncate_range(inode: file_inode(f: i915_tt->filp),
443 start: 0, end: (loff_t)-1);
444 fput(fetch_and_zero(&i915_tt->filp));
445 }
446
447 obj->write_domain = 0;
448 obj->read_domains = 0;
449 i915_ttm_adjust_gem_after_move(obj);
450 i915_ttm_free_cached_io_rsgt(obj);
451 obj->mm.madv = __I915_MADV_PURGED;
452
453 return 0;
454}
455
456static int i915_ttm_shrink(struct drm_i915_gem_object *obj, unsigned int flags)
457{
458 struct ttm_buffer_object *bo = i915_gem_to_ttm(obj);
459 struct i915_ttm_tt *i915_tt =
460 container_of(bo->ttm, typeof(*i915_tt), ttm);
461 struct ttm_operation_ctx ctx = {
462 .interruptible = true,
463 .no_wait_gpu = flags & I915_GEM_OBJECT_SHRINK_NO_GPU_WAIT,
464 };
465 struct ttm_placement place = {};
466 int ret;
467
468 if (!bo->ttm || i915_ttm_cpu_maps_iomem(mem: bo->resource))
469 return 0;
470
471 GEM_BUG_ON(!i915_tt->is_shmem);
472
473 if (!i915_tt->filp)
474 return 0;
475
476 ret = ttm_bo_wait_ctx(bo, ctx: &ctx);
477 if (ret)
478 return ret;
479
480 switch (obj->mm.madv) {
481 case I915_MADV_DONTNEED:
482 return i915_ttm_purge(obj);
483 case __I915_MADV_PURGED:
484 return 0;
485 }
486
487 if (bo->ttm->page_flags & TTM_TT_FLAG_SWAPPED)
488 return 0;
489
490 bo->ttm->page_flags |= TTM_TT_FLAG_SWAPPED;
491 ret = ttm_bo_validate(bo, placement: &place, ctx: &ctx);
492 if (ret) {
493 bo->ttm->page_flags &= ~TTM_TT_FLAG_SWAPPED;
494 return ret;
495 }
496
497 if (flags & I915_GEM_OBJECT_SHRINK_WRITEBACK)
498 __shmem_writeback(size: obj->base.size, mapping: i915_tt->filp->f_mapping);
499
500 return 0;
501}
502
503static void i915_ttm_delete_mem_notify(struct ttm_buffer_object *bo)
504{
505 struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
506
507 /*
508 * This gets called twice by ttm, so long as we have a ttm resource or
509 * ttm_tt then we can still safely call this. Due to pipeline-gutting,
510 * we maybe have NULL bo->resource, but in that case we should always
511 * have a ttm alive (like if the pages are swapped out).
512 */
513 if ((bo->resource || bo->ttm) && !i915_ttm_is_ghost_object(bo)) {
514 __i915_gem_object_pages_fini(obj);
515 i915_ttm_free_cached_io_rsgt(obj);
516 }
517}
518
519static 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(rsgt: &i915_tt->cached_rsgt);
527
528 st = &i915_tt->cached_rsgt.table;
529 ret = sg_alloc_table_from_pages_segment(sgt: st,
530 pages: ttm->pages, n_pages: ttm->num_pages,
531 offset: 0, size: (unsigned long)ttm->num_pages << PAGE_SHIFT,
532 max_segment: i915_sg_segment_size(dev: i915_tt->dev), GFP_KERNEL);
533 if (ret) {
534 st->sgl = NULL;
535 return ERR_PTR(error: ret);
536 }
537
538 ret = dma_map_sgtable(dev: i915_tt->dev, sgt: st, dir: DMA_BIDIRECTIONAL, attrs: 0);
539 if (ret) {
540 sg_free_table(st);
541 return ERR_PTR(error: ret);
542 }
543
544 return i915_refct_sgt_get(rsgt: &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 */
561struct i915_refct_sgt *
562i915_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(mem: res))
569 return i915_ttm_tt_get_st(ttm: 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(mem: obj->mm.region,
585 res,
586 page_alignment);
587 if (IS_ERR(ptr: rsgt))
588 return rsgt;
589
590 obj->ttm.cached_io_rsgt = rsgt;
591 }
592 return i915_refct_sgt_get(rsgt: obj->ttm.cached_io_rsgt);
593 }
594
595 return intel_region_ttm_resource_to_rsgt(mem: obj->mm.region, res,
596 page_alignment);
597}
598
599static int i915_ttm_truncate(struct drm_i915_gem_object *obj)
600{
601 struct ttm_buffer_object *bo = i915_gem_to_ttm(obj);
602 long err;
603
604 WARN_ON_ONCE(obj->mm.madv == I915_MADV_WILLNEED);
605
606 err = dma_resv_wait_timeout(obj: bo->base.resv, usage: DMA_RESV_USAGE_BOOKKEEP,
607 intr: true, timeout: 15 * HZ);
608 if (err < 0)
609 return err;
610 if (err == 0)
611 return -EBUSY;
612
613 err = i915_ttm_move_notify(bo);
614 if (err)
615 return err;
616
617 return i915_ttm_purge(obj);
618}
619
620static void i915_ttm_swap_notify(struct ttm_buffer_object *bo)
621{
622 struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
623 int ret;
624
625 if (i915_ttm_is_ghost_object(bo))
626 return;
627
628 ret = i915_ttm_move_notify(bo);
629 GEM_WARN_ON(ret);
630 GEM_WARN_ON(obj->ttm.cached_io_rsgt);
631 if (!ret && obj->mm.madv != I915_MADV_WILLNEED)
632 i915_ttm_purge(obj);
633}
634
635/**
636 * i915_ttm_resource_mappable - Return true if the ttm resource is CPU
637 * accessible.
638 * @res: The TTM resource to check.
639 *
640 * This is interesting on small-BAR systems where we may encounter lmem objects
641 * that can't be accessed via the CPU.
642 */
643bool i915_ttm_resource_mappable(struct ttm_resource *res)
644{
645 struct i915_ttm_buddy_resource *bman_res = to_ttm_buddy_resource(res);
646
647 if (!i915_ttm_cpu_maps_iomem(mem: res))
648 return true;
649
650 return bman_res->used_visible_size == PFN_UP(bman_res->base.size);
651}
652
653static int i915_ttm_io_mem_reserve(struct ttm_device *bdev, struct ttm_resource *mem)
654{
655 struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo: mem->bo);
656 bool unknown_state;
657
658 if (i915_ttm_is_ghost_object(bo: mem->bo))
659 return -EINVAL;
660
661 if (!kref_get_unless_zero(kref: &obj->base.refcount))
662 return -EINVAL;
663
664 assert_object_held(obj);
665
666 unknown_state = i915_gem_object_has_unknown_state(obj);
667 i915_gem_object_put(obj);
668 if (unknown_state)
669 return -EINVAL;
670
671 if (!i915_ttm_cpu_maps_iomem(mem))
672 return 0;
673
674 if (!i915_ttm_resource_mappable(res: mem))
675 return -EINVAL;
676
677 mem->bus.caching = ttm_write_combined;
678 mem->bus.is_iomem = true;
679
680 return 0;
681}
682
683static unsigned long i915_ttm_io_mem_pfn(struct ttm_buffer_object *bo,
684 unsigned long page_offset)
685{
686 struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
687 struct scatterlist *sg;
688 unsigned long base;
689 unsigned int ofs;
690
691 GEM_BUG_ON(i915_ttm_is_ghost_object(bo));
692 GEM_WARN_ON(bo->ttm);
693
694 base = obj->mm.region->iomap.base - obj->mm.region->region.start;
695 sg = i915_gem_object_page_iter_get_sg(obj, &obj->ttm.get_io_page, page_offset, &ofs);
696
697 return ((base + sg_dma_address(sg)) >> PAGE_SHIFT) + ofs;
698}
699
700static int i915_ttm_access_memory(struct ttm_buffer_object *bo,
701 unsigned long offset, void *buf,
702 int len, int write)
703{
704 struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
705 resource_size_t iomap = obj->mm.region->iomap.base -
706 obj->mm.region->region.start;
707 unsigned long page = offset >> PAGE_SHIFT;
708 unsigned long bytes_left = len;
709
710 /*
711 * TODO: For now just let it fail if the resource is non-mappable,
712 * otherwise we need to perform the memcpy from the gpu here, without
713 * interfering with the object (like moving the entire thing).
714 */
715 if (!i915_ttm_resource_mappable(res: bo->resource))
716 return -EIO;
717
718 offset -= page << PAGE_SHIFT;
719 do {
720 unsigned long bytes = min(bytes_left, PAGE_SIZE - offset);
721 void __iomem *ptr;
722 dma_addr_t daddr;
723
724 daddr = i915_gem_object_get_dma_address(obj, page);
725 ptr = ioremap_wc(offset: iomap + daddr + offset, size: bytes);
726 if (!ptr)
727 return -EIO;
728
729 if (write)
730 memcpy_toio(ptr, buf, bytes);
731 else
732 memcpy_fromio(buf, ptr, bytes);
733 iounmap(addr: ptr);
734
735 page++;
736 buf += bytes;
737 bytes_left -= bytes;
738 offset = 0;
739 } while (bytes_left);
740
741 return len;
742}
743
744/*
745 * All callbacks need to take care not to downcast a struct ttm_buffer_object
746 * without checking its subclass, since it might be a TTM ghost object.
747 */
748static struct ttm_device_funcs i915_ttm_bo_driver = {
749 .ttm_tt_create = i915_ttm_tt_create,
750 .ttm_tt_populate = i915_ttm_tt_populate,
751 .ttm_tt_unpopulate = i915_ttm_tt_unpopulate,
752 .ttm_tt_destroy = i915_ttm_tt_destroy,
753 .eviction_valuable = i915_ttm_eviction_valuable,
754 .evict_flags = i915_ttm_evict_flags,
755 .move = i915_ttm_move,
756 .swap_notify = i915_ttm_swap_notify,
757 .delete_mem_notify = i915_ttm_delete_mem_notify,
758 .io_mem_reserve = i915_ttm_io_mem_reserve,
759 .io_mem_pfn = i915_ttm_io_mem_pfn,
760 .access_memory = i915_ttm_access_memory,
761};
762
763/**
764 * i915_ttm_driver - Return a pointer to the TTM device funcs
765 *
766 * Return: Pointer to statically allocated TTM device funcs.
767 */
768struct ttm_device_funcs *i915_ttm_driver(void)
769{
770 return &i915_ttm_bo_driver;
771}
772
773static int __i915_ttm_get_pages(struct drm_i915_gem_object *obj,
774 struct ttm_placement *placement)
775{
776 struct ttm_buffer_object *bo = i915_gem_to_ttm(obj);
777 struct ttm_operation_ctx ctx = {
778 .interruptible = true,
779 .no_wait_gpu = false,
780 };
781 struct ttm_placement initial_placement;
782 struct ttm_place initial_place;
783 int ret;
784
785 /* First try only the requested placement. No eviction. */
786 initial_placement.num_placement = 1;
787 memcpy(to: &initial_place, from: placement->placement, len: sizeof(struct ttm_place));
788 initial_place.flags |= TTM_PL_FLAG_DESIRED;
789 initial_placement.placement = &initial_place;
790 ret = ttm_bo_validate(bo, placement: &initial_placement, ctx: &ctx);
791 if (ret) {
792 ret = i915_ttm_err_to_gem(err: ret);
793 /*
794 * Anything that wants to restart the operation gets to
795 * do that.
796 */
797 if (ret == -EDEADLK || ret == -EINTR || ret == -ERESTARTSYS ||
798 ret == -EAGAIN)
799 return ret;
800
801 /*
802 * If the initial attempt fails, allow all accepted placements,
803 * evicting if necessary.
804 */
805 ret = ttm_bo_validate(bo, placement, ctx: &ctx);
806 if (ret)
807 return i915_ttm_err_to_gem(err: ret);
808 }
809
810 if (bo->ttm && !ttm_tt_is_populated(tt: bo->ttm)) {
811 ret = ttm_bo_populate(bo, ctx: &ctx);
812 if (ret)
813 return ret;
814
815 i915_ttm_adjust_domains_after_move(obj);
816 i915_ttm_adjust_gem_after_move(obj);
817 }
818
819 if (!i915_gem_object_has_pages(obj)) {
820 struct i915_refct_sgt *rsgt =
821 i915_ttm_resource_get_st(obj, res: bo->resource);
822
823 if (IS_ERR(ptr: rsgt))
824 return PTR_ERR(ptr: rsgt);
825
826 GEM_BUG_ON(obj->mm.rsgt);
827 obj->mm.rsgt = rsgt;
828 __i915_gem_object_set_pages(obj, pages: &rsgt->table);
829 }
830
831 GEM_BUG_ON(bo->ttm && ((obj->base.size >> PAGE_SHIFT) < bo->ttm->num_pages));
832 i915_ttm_adjust_lru(obj);
833 return ret;
834}
835
836static int i915_ttm_get_pages(struct drm_i915_gem_object *obj)
837{
838 struct ttm_place places[I915_TTM_MAX_PLACEMENTS + 1];
839 struct ttm_placement placement;
840
841 /* restricted by sg_alloc_table */
842 if (overflows_type(obj->base.size >> PAGE_SHIFT, unsigned int))
843 return -E2BIG;
844
845 GEM_BUG_ON(obj->mm.n_placements > I915_TTM_MAX_PLACEMENTS);
846
847 /* Move to the requested placement. */
848 i915_ttm_placement_from_obj(obj, places, placement: &placement);
849
850 return __i915_ttm_get_pages(obj, placement: &placement);
851}
852
853/**
854 * DOC: Migration vs eviction
855 *
856 * GEM migration may not be the same as TTM migration / eviction. If
857 * the TTM core decides to evict an object it may be evicted to a
858 * TTM memory type that is not in the object's allowable GEM regions, or
859 * in fact theoretically to a TTM memory type that doesn't correspond to
860 * a GEM memory region. In that case the object's GEM region is not
861 * updated, and the data is migrated back to the GEM region at
862 * get_pages time. TTM may however set up CPU ptes to the object even
863 * when it is evicted.
864 * Gem forced migration using the i915_ttm_migrate() op, is allowed even
865 * to regions that are not in the object's list of allowable placements.
866 */
867static int __i915_ttm_migrate(struct drm_i915_gem_object *obj,
868 struct intel_memory_region *mr,
869 unsigned int flags)
870{
871 struct ttm_place requested;
872 struct ttm_placement placement;
873 int ret;
874
875 i915_ttm_place_from_region(mr, place: &requested, offset: obj->bo_offset,
876 size: obj->base.size, flags);
877 placement.num_placement = 1;
878 placement.placement = &requested;
879
880 ret = __i915_ttm_get_pages(obj, placement: &placement);
881 if (ret)
882 return ret;
883
884 /*
885 * Reinitialize the region bindings. This is primarily
886 * required for objects where the new region is not in
887 * its allowable placements.
888 */
889 if (obj->mm.region != mr) {
890 i915_gem_object_release_memory_region(obj);
891 i915_gem_object_init_memory_region(obj, mem: mr);
892 }
893
894 return 0;
895}
896
897static int i915_ttm_migrate(struct drm_i915_gem_object *obj,
898 struct intel_memory_region *mr,
899 unsigned int flags)
900{
901 return __i915_ttm_migrate(obj, mr, flags);
902}
903
904static void i915_ttm_put_pages(struct drm_i915_gem_object *obj,
905 struct sg_table *st)
906{
907 /*
908 * We're currently not called from a shrinker, so put_pages()
909 * typically means the object is about to destroyed, or called
910 * from move_notify(). So just avoid doing much for now.
911 * If the object is not destroyed next, The TTM eviction logic
912 * and shrinkers will move it out if needed.
913 */
914
915 if (obj->mm.rsgt)
916 i915_refct_sgt_put(fetch_and_zero(&obj->mm.rsgt));
917}
918
919/**
920 * i915_ttm_adjust_lru - Adjust an object's position on relevant LRU lists.
921 * @obj: The object
922 */
923void i915_ttm_adjust_lru(struct drm_i915_gem_object *obj)
924{
925 struct ttm_buffer_object *bo = i915_gem_to_ttm(obj);
926 struct i915_ttm_tt *i915_tt =
927 container_of(bo->ttm, typeof(*i915_tt), ttm);
928 bool shrinkable =
929 bo->ttm && i915_tt->filp && ttm_tt_is_populated(tt: bo->ttm);
930
931 /*
932 * Don't manipulate the TTM LRUs while in TTM bo destruction.
933 * We're called through i915_ttm_delete_mem_notify().
934 */
935 if (!kref_read(kref: &bo->kref))
936 return;
937
938 /*
939 * We skip managing the shrinker LRU in set_pages() and just manage
940 * everything here. This does at least solve the issue with having
941 * temporary shmem mappings(like with evicted lmem) not being visible to
942 * the shrinker. Only our shmem objects are shrinkable, everything else
943 * we keep as unshrinkable.
944 *
945 * To make sure everything plays nice we keep an extra shrink pin in TTM
946 * if the underlying pages are not currently shrinkable. Once we release
947 * our pin, like when the pages are moved to shmem, the pages will then
948 * be added to the shrinker LRU, assuming the caller isn't also holding
949 * a pin.
950 *
951 * TODO: consider maybe also bumping the shrinker list here when we have
952 * already unpinned it, which should give us something more like an LRU.
953 *
954 * TODO: There is a small window of opportunity for this function to
955 * get called from eviction after we've dropped the last GEM refcount,
956 * but before the TTM deleted flag is set on the object. Avoid
957 * adjusting the shrinker list in such cases, since the object is
958 * not available to the shrinker anyway due to its zero refcount.
959 * To fix this properly we should move to a TTM shrinker LRU list for
960 * these objects.
961 */
962 if (kref_get_unless_zero(kref: &obj->base.refcount)) {
963 if (shrinkable != obj->mm.ttm_shrinkable) {
964 if (shrinkable) {
965 if (obj->mm.madv == I915_MADV_WILLNEED)
966 __i915_gem_object_make_shrinkable(obj);
967 else
968 __i915_gem_object_make_purgeable(obj);
969 } else {
970 i915_gem_object_make_unshrinkable(obj);
971 }
972
973 obj->mm.ttm_shrinkable = shrinkable;
974 }
975 i915_gem_object_put(obj);
976 }
977
978 /*
979 * Put on the correct LRU list depending on the MADV status
980 */
981 spin_lock(lock: &bo->bdev->lru_lock);
982 if (shrinkable) {
983 /* Try to keep shmem_tt from being considered for shrinking. */
984 bo->priority = TTM_MAX_BO_PRIORITY - 1;
985 } else if (obj->mm.madv != I915_MADV_WILLNEED) {
986 bo->priority = I915_TTM_PRIO_PURGE;
987 } else if (!i915_gem_object_has_pages(obj)) {
988 bo->priority = I915_TTM_PRIO_NO_PAGES;
989 } else {
990 struct ttm_resource_manager *man =
991 ttm_manager_type(bdev: bo->bdev, mem_type: bo->resource->mem_type);
992
993 /*
994 * If we need to place an LMEM resource which doesn't need CPU
995 * access then we should try not to victimize mappable objects
996 * first, since we likely end up stealing more of the mappable
997 * portion. And likewise when we try to find space for a mappable
998 * object, we know not to ever victimize objects that don't
999 * occupy any mappable pages.
1000 */
1001 if (i915_ttm_cpu_maps_iomem(mem: bo->resource) &&
1002 i915_ttm_buddy_man_visible_size(man) < man->size &&
1003 !(obj->flags & I915_BO_ALLOC_GPU_ONLY))
1004 bo->priority = I915_TTM_PRIO_NEEDS_CPU_ACCESS;
1005 else
1006 bo->priority = I915_TTM_PRIO_HAS_PAGES;
1007 }
1008
1009 ttm_bo_move_to_lru_tail(bo);
1010 spin_unlock(lock: &bo->bdev->lru_lock);
1011}
1012
1013/*
1014 * TTM-backed gem object destruction requires some clarification.
1015 * Basically we have two possibilities here. We can either rely on the
1016 * i915 delayed destruction and put the TTM object when the object
1017 * is idle. This would be detected by TTM which would bypass the
1018 * TTM delayed destroy handling. The other approach is to put the TTM
1019 * object early and rely on the TTM destroyed handling, and then free
1020 * the leftover parts of the GEM object once TTM's destroyed list handling is
1021 * complete. For now, we rely on the latter for two reasons:
1022 * a) TTM can evict an object even when it's on the delayed destroy list,
1023 * which in theory allows for complete eviction.
1024 * b) There is work going on in TTM to allow freeing an object even when
1025 * it's not idle, and using the TTM destroyed list handling could help us
1026 * benefit from that.
1027 */
1028static void i915_ttm_delayed_free(struct drm_i915_gem_object *obj)
1029{
1030 GEM_BUG_ON(!obj->ttm.created);
1031
1032 ttm_bo_put(bo: i915_gem_to_ttm(obj));
1033}
1034
1035static vm_fault_t vm_fault_ttm(struct vm_fault *vmf)
1036{
1037 struct vm_area_struct *area = vmf->vma;
1038 struct ttm_buffer_object *bo = area->vm_private_data;
1039 struct drm_device *dev = bo->base.dev;
1040 struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
1041 intel_wakeref_t wakeref = NULL;
1042 vm_fault_t ret;
1043 int idx;
1044
1045 /* Sanity check that we allow writing into this object */
1046 if (unlikely(i915_gem_object_is_readonly(obj) &&
1047 area->vm_flags & VM_WRITE))
1048 return VM_FAULT_SIGBUS;
1049
1050 ret = ttm_bo_vm_reserve(bo, vmf);
1051 if (ret)
1052 return ret;
1053
1054 if (obj->mm.madv != I915_MADV_WILLNEED) {
1055 dma_resv_unlock(obj: bo->base.resv);
1056 return VM_FAULT_SIGBUS;
1057 }
1058
1059 /*
1060 * This must be swapped out with shmem ttm_tt (pipeline-gutting).
1061 * Calling ttm_bo_validate() here with TTM_PL_SYSTEM should only go as
1062 * far as far doing a ttm_bo_move_null(), which should skip all the
1063 * other junk.
1064 */
1065 if (!bo->resource) {
1066 struct ttm_operation_ctx ctx = {
1067 .interruptible = true,
1068 .no_wait_gpu = true, /* should be idle already */
1069 };
1070 int err;
1071
1072 GEM_BUG_ON(!bo->ttm || !(bo->ttm->page_flags & TTM_TT_FLAG_SWAPPED));
1073
1074 err = ttm_bo_validate(bo, placement: i915_ttm_sys_placement(), ctx: &ctx);
1075 if (err) {
1076 dma_resv_unlock(obj: bo->base.resv);
1077 return VM_FAULT_SIGBUS;
1078 }
1079 } else if (!i915_ttm_resource_mappable(res: bo->resource)) {
1080 int err = -ENODEV;
1081 int i;
1082
1083 for (i = 0; i < obj->mm.n_placements; i++) {
1084 struct intel_memory_region *mr = obj->mm.placements[i];
1085 unsigned int flags;
1086
1087 if (!resource_size(res: &mr->io) && mr->type != INTEL_MEMORY_SYSTEM)
1088 continue;
1089
1090 flags = obj->flags;
1091 flags &= ~I915_BO_ALLOC_GPU_ONLY;
1092 err = __i915_ttm_migrate(obj, mr, flags);
1093 if (!err)
1094 break;
1095 }
1096
1097 if (err) {
1098 drm_dbg_ratelimited(dev,
1099 "Unable to make resource CPU accessible(err = %pe)\n",
1100 ERR_PTR(err));
1101 dma_resv_unlock(obj: bo->base.resv);
1102 ret = VM_FAULT_SIGBUS;
1103 goto out_rpm;
1104 }
1105 }
1106
1107 if (i915_ttm_cpu_maps_iomem(mem: bo->resource))
1108 wakeref = intel_runtime_pm_get(rpm: &to_i915(dev: obj->base.dev)->runtime_pm);
1109
1110 if (drm_dev_enter(dev, idx: &idx)) {
1111 ret = ttm_bo_vm_fault_reserved(vmf, prot: vmf->vma->vm_page_prot,
1112 TTM_BO_VM_NUM_PREFAULT);
1113 drm_dev_exit(idx);
1114 } else {
1115 ret = ttm_bo_vm_dummy_page(vmf, prot: vmf->vma->vm_page_prot);
1116 }
1117
1118 if (ret == VM_FAULT_RETRY && !(vmf->flags & FAULT_FLAG_RETRY_NOWAIT))
1119 goto out_rpm;
1120
1121 /*
1122 * ttm_bo_vm_reserve() already has dma_resv_lock.
1123 * userfault_count is protected by dma_resv lock and rpm wakeref.
1124 */
1125 if (ret == VM_FAULT_NOPAGE && wakeref && !obj->userfault_count) {
1126 obj->userfault_count = 1;
1127 spin_lock(lock: &to_i915(dev: obj->base.dev)->runtime_pm.lmem_userfault_lock);
1128 list_add(new: &obj->userfault_link, head: &to_i915(dev: obj->base.dev)->runtime_pm.lmem_userfault_list);
1129 spin_unlock(lock: &to_i915(dev: obj->base.dev)->runtime_pm.lmem_userfault_lock);
1130
1131 GEM_WARN_ON(!i915_ttm_cpu_maps_iomem(bo->resource));
1132 }
1133
1134 if (wakeref && CONFIG_DRM_I915_USERFAULT_AUTOSUSPEND != 0)
1135 intel_wakeref_auto(wf: &to_i915(dev: obj->base.dev)->runtime_pm.userfault_wakeref,
1136 timeout: msecs_to_jiffies_timeout(CONFIG_DRM_I915_USERFAULT_AUTOSUSPEND));
1137
1138 i915_ttm_adjust_lru(obj);
1139
1140 dma_resv_unlock(obj: bo->base.resv);
1141
1142out_rpm:
1143 if (wakeref)
1144 intel_runtime_pm_put(rpm: &to_i915(dev: obj->base.dev)->runtime_pm, wref: wakeref);
1145
1146 return ret;
1147}
1148
1149static int
1150vm_access_ttm(struct vm_area_struct *area, unsigned long addr,
1151 void *buf, int len, int write)
1152{
1153 struct drm_i915_gem_object *obj =
1154 i915_ttm_to_gem(bo: area->vm_private_data);
1155
1156 if (i915_gem_object_is_readonly(obj) && write)
1157 return -EACCES;
1158
1159 return ttm_bo_vm_access(vma: area, addr, buf, len, write);
1160}
1161
1162static void ttm_vm_open(struct vm_area_struct *vma)
1163{
1164 struct drm_i915_gem_object *obj =
1165 i915_ttm_to_gem(bo: vma->vm_private_data);
1166
1167 GEM_BUG_ON(i915_ttm_is_ghost_object(vma->vm_private_data));
1168 i915_gem_object_get(obj);
1169}
1170
1171static void ttm_vm_close(struct vm_area_struct *vma)
1172{
1173 struct drm_i915_gem_object *obj =
1174 i915_ttm_to_gem(bo: vma->vm_private_data);
1175
1176 GEM_BUG_ON(i915_ttm_is_ghost_object(vma->vm_private_data));
1177 i915_gem_object_put(obj);
1178}
1179
1180static const struct vm_operations_struct vm_ops_ttm = {
1181 .fault = vm_fault_ttm,
1182 .access = vm_access_ttm,
1183 .open = ttm_vm_open,
1184 .close = ttm_vm_close,
1185};
1186
1187static u64 i915_ttm_mmap_offset(struct drm_i915_gem_object *obj)
1188{
1189 /* The ttm_bo must be allocated with I915_BO_ALLOC_USER */
1190 GEM_BUG_ON(!drm_mm_node_allocated(&obj->base.vma_node.vm_node));
1191
1192 return drm_vma_node_offset_addr(node: &obj->base.vma_node);
1193}
1194
1195static void i915_ttm_unmap_virtual(struct drm_i915_gem_object *obj)
1196{
1197 struct ttm_buffer_object *bo = i915_gem_to_ttm(obj);
1198 intel_wakeref_t wakeref = NULL;
1199
1200 assert_object_held_shared(obj);
1201
1202 if (i915_ttm_cpu_maps_iomem(mem: bo->resource)) {
1203 wakeref = intel_runtime_pm_get(rpm: &to_i915(dev: obj->base.dev)->runtime_pm);
1204
1205 /* userfault_count is protected by obj lock and rpm wakeref. */
1206 if (obj->userfault_count) {
1207 spin_lock(lock: &to_i915(dev: obj->base.dev)->runtime_pm.lmem_userfault_lock);
1208 list_del(entry: &obj->userfault_link);
1209 spin_unlock(lock: &to_i915(dev: obj->base.dev)->runtime_pm.lmem_userfault_lock);
1210 obj->userfault_count = 0;
1211 }
1212 }
1213
1214 GEM_WARN_ON(obj->userfault_count);
1215
1216 ttm_bo_unmap_virtual(bo: i915_gem_to_ttm(obj));
1217
1218 if (wakeref)
1219 intel_runtime_pm_put(rpm: &to_i915(dev: obj->base.dev)->runtime_pm, wref: wakeref);
1220}
1221
1222static const struct drm_i915_gem_object_ops i915_gem_ttm_obj_ops = {
1223 .name = "i915_gem_object_ttm",
1224 .flags = I915_GEM_OBJECT_IS_SHRINKABLE |
1225 I915_GEM_OBJECT_SELF_MANAGED_SHRINK_LIST,
1226
1227 .get_pages = i915_ttm_get_pages,
1228 .put_pages = i915_ttm_put_pages,
1229 .truncate = i915_ttm_truncate,
1230 .shrink = i915_ttm_shrink,
1231
1232 .adjust_lru = i915_ttm_adjust_lru,
1233 .delayed_free = i915_ttm_delayed_free,
1234 .migrate = i915_ttm_migrate,
1235
1236 .mmap_offset = i915_ttm_mmap_offset,
1237 .unmap_virtual = i915_ttm_unmap_virtual,
1238 .mmap_ops = &vm_ops_ttm,
1239};
1240
1241void i915_ttm_bo_destroy(struct ttm_buffer_object *bo)
1242{
1243 struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);
1244
1245 i915_gem_object_release_memory_region(obj);
1246 mutex_destroy(lock: &obj->ttm.get_io_page.lock);
1247
1248 if (obj->ttm.created) {
1249 /*
1250 * We freely manage the shrinker LRU outide of the mm.pages life
1251 * cycle. As a result when destroying the object we should be
1252 * extra paranoid and ensure we remove it from the LRU, before
1253 * we free the object.
1254 *
1255 * Touching the ttm_shrinkable outside of the object lock here
1256 * should be safe now that the last GEM object ref was dropped.
1257 */
1258 if (obj->mm.ttm_shrinkable)
1259 i915_gem_object_make_unshrinkable(obj);
1260
1261 i915_ttm_backup_free(obj);
1262
1263 /* This releases all gem object bindings to the backend. */
1264 __i915_gem_free_object(obj);
1265
1266 call_rcu(head: &obj->rcu, func: __i915_gem_free_object_rcu);
1267 } else {
1268 __i915_gem_object_fini(obj);
1269 }
1270}
1271
1272/*
1273 * __i915_gem_ttm_object_init - Initialize a ttm-backed i915 gem object
1274 * @mem: The initial memory region for the object.
1275 * @obj: The gem object.
1276 * @size: Object size in bytes.
1277 * @flags: gem object flags.
1278 *
1279 * Return: 0 on success, negative error code on failure.
1280 */
1281int __i915_gem_ttm_object_init(struct intel_memory_region *mem,
1282 struct drm_i915_gem_object *obj,
1283 resource_size_t offset,
1284 resource_size_t size,
1285 resource_size_t page_size,
1286 unsigned int flags)
1287{
1288 static struct lock_class_key lock_class;
1289 struct drm_i915_private *i915 = mem->i915;
1290 struct ttm_operation_ctx ctx = {
1291 .interruptible = true,
1292 .no_wait_gpu = false,
1293 };
1294 enum ttm_bo_type bo_type;
1295 int ret;
1296
1297 drm_gem_private_object_init(dev: &i915->drm, obj: &obj->base, size);
1298 i915_gem_object_init(obj, ops: &i915_gem_ttm_obj_ops, key: &lock_class, alloc_flags: flags);
1299
1300 obj->bo_offset = offset;
1301
1302 /* Don't put on a region list until we're either locked or fully initialized. */
1303 obj->mm.region = mem;
1304 INIT_LIST_HEAD(list: &obj->mm.region_link);
1305
1306 INIT_RADIX_TREE(&obj->ttm.get_io_page.radix, GFP_KERNEL | __GFP_NOWARN);
1307 mutex_init(&obj->ttm.get_io_page.lock);
1308 bo_type = (obj->flags & I915_BO_ALLOC_USER) ? ttm_bo_type_device :
1309 ttm_bo_type_kernel;
1310
1311 obj->base.vma_node.driver_private = i915_gem_to_ttm(obj);
1312
1313 /* Forcing the page size is kernel internal only */
1314 GEM_BUG_ON(page_size && obj->mm.n_placements);
1315
1316 /*
1317 * Keep an extra shrink pin to prevent the object from being made
1318 * shrinkable too early. If the ttm_tt is ever allocated in shmem, we
1319 * drop the pin. The TTM backend manages the shrinker LRU itself,
1320 * outside of the normal mm.pages life cycle.
1321 */
1322 i915_gem_object_make_unshrinkable(obj);
1323
1324 /*
1325 * If this function fails, it will call the destructor, but
1326 * our caller still owns the object. So no freeing in the
1327 * destructor until obj->ttm.created is true.
1328 * Similarly, in delayed_destroy, we can't call ttm_bo_put()
1329 * until successful initialization.
1330 */
1331 ret = ttm_bo_init_reserved(bdev: &i915->bdev, bo: i915_gem_to_ttm(obj), type: bo_type,
1332 placement: &i915_sys_placement, alignment: page_size >> PAGE_SHIFT,
1333 ctx: &ctx, NULL, NULL, destroy: i915_ttm_bo_destroy);
1334
1335 /*
1336 * XXX: The ttm_bo_init_reserved() functions returns -ENOSPC if the size
1337 * is too big to add vma. The direct function that returns -ENOSPC is
1338 * drm_mm_insert_node_in_range(). To handle the same error as other code
1339 * that returns -E2BIG when the size is too large, it converts -ENOSPC to
1340 * -E2BIG.
1341 */
1342 if (size >> PAGE_SHIFT > INT_MAX && ret == -ENOSPC)
1343 ret = -E2BIG;
1344
1345 if (ret)
1346 return i915_ttm_err_to_gem(err: ret);
1347
1348 obj->ttm.created = true;
1349 i915_gem_object_release_memory_region(obj);
1350 i915_gem_object_init_memory_region(obj, mem);
1351 i915_ttm_adjust_domains_after_move(obj);
1352 i915_ttm_adjust_gem_after_move(obj);
1353 i915_gem_object_unlock(obj);
1354
1355 return 0;
1356}
1357
1358static const struct intel_memory_region_ops ttm_system_region_ops = {
1359 .init_object = __i915_gem_ttm_object_init,
1360 .release = intel_region_ttm_fini,
1361};
1362
1363struct intel_memory_region *
1364i915_gem_ttm_system_setup(struct drm_i915_private *i915,
1365 u16 type, u16 instance)
1366{
1367 struct intel_memory_region *mr;
1368
1369 mr = intel_memory_region_create(i915, start: 0,
1370 size: totalram_pages() << PAGE_SHIFT,
1371 PAGE_SIZE, io_start: 0, io_size: 0,
1372 type, instance,
1373 ops: &ttm_system_region_ops);
1374 if (IS_ERR(ptr: mr))
1375 return mr;
1376
1377 intel_memory_region_set_name(mem: mr, fmt: "system-ttm");
1378 return mr;
1379}
1380