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1/* SPDX-License-Identifier: GPL-2.0 OR MIT */
2/**************************************************************************
3 *
4 * Copyright (c) 2007-2009 VMware, Inc., Palo Alto, CA., USA
5 * All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the
9 * "Software"), to deal in the Software without restriction, including
10 * without limitation the rights to use, copy, modify, merge, publish,
11 * distribute, sub license, and/or sell copies of the Software, and to
12 * permit persons to whom the Software is furnished to do so, subject to
13 * the following conditions:
14 *
15 * The above copyright notice and this permission notice (including the
16 * next paragraph) shall be included in all copies or substantial portions
17 * of the Software.
18 *
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
22 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
23 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
24 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
25 * USE OR OTHER DEALINGS IN THE SOFTWARE.
26 *
27 **************************************************************************/
28/*
29 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
30 */
31
32#include <linux/vmalloc.h>
33
34#include <drm/ttm/ttm_bo.h>
35#include <drm/ttm/ttm_placement.h>
36#include <drm/ttm/ttm_tt.h>
37
38#include <drm/drm_cache.h>
39
40struct ttm_transfer_obj {
41 struct ttm_buffer_object base;
42 struct ttm_buffer_object *bo;
43};
44
45int ttm_mem_io_reserve(struct ttm_device *bdev,
46 struct ttm_resource *mem)
47{
48 if (mem->bus.offset || mem->bus.addr)
49 return 0;
50
51 mem->bus.is_iomem = false;
52 if (!bdev->funcs->io_mem_reserve)
53 return 0;
54
55 return bdev->funcs->io_mem_reserve(bdev, mem);
56}
57
58void ttm_mem_io_free(struct ttm_device *bdev,
59 struct ttm_resource *mem)
60{
61 if (!mem)
62 return;
63
64 if (!mem->bus.offset && !mem->bus.addr)
65 return;
66
67 if (bdev->funcs->io_mem_free)
68 bdev->funcs->io_mem_free(bdev, mem);
69
70 mem->bus.offset = 0;
71 mem->bus.addr = NULL;
72}
73
74/**
75 * ttm_move_memcpy - Helper to perform a memcpy ttm move operation.
76 * @clear: Whether to clear rather than copy.
77 * @num_pages: Number of pages of the operation.
78 * @dst_iter: A struct ttm_kmap_iter representing the destination resource.
79 * @src_iter: A struct ttm_kmap_iter representing the source resource.
80 *
81 * This function is intended to be able to move out async under a
82 * dma-fence if desired.
83 */
84void ttm_move_memcpy(bool clear,
85 u32 num_pages,
86 struct ttm_kmap_iter *dst_iter,
87 struct ttm_kmap_iter *src_iter)
88{
89 const struct ttm_kmap_iter_ops *dst_ops = dst_iter->ops;
90 const struct ttm_kmap_iter_ops *src_ops = src_iter->ops;
91 struct iosys_map src_map, dst_map;
92 pgoff_t i;
93
94 /* Single TTM move. NOP */
95 if (dst_ops->maps_tt && src_ops->maps_tt)
96 return;
97
98 /* Don't move nonexistent data. Clear destination instead. */
99 if (clear) {
100 for (i = 0; i < num_pages; ++i) {
101 dst_ops->map_local(dst_iter, &dst_map, i);
102 if (dst_map.is_iomem)
103 memset_io(dst_map.vaddr_iomem, 0, PAGE_SIZE);
104 else
105 memset(dst_map.vaddr, 0, PAGE_SIZE);
106 if (dst_ops->unmap_local)
107 dst_ops->unmap_local(dst_iter, &dst_map);
108 }
109 return;
110 }
111
112 for (i = 0; i < num_pages; ++i) {
113 dst_ops->map_local(dst_iter, &dst_map, i);
114 src_ops->map_local(src_iter, &src_map, i);
115
116 drm_memcpy_from_wc(&dst_map, &src_map, PAGE_SIZE);
117
118 if (src_ops->unmap_local)
119 src_ops->unmap_local(src_iter, &src_map);
120 if (dst_ops->unmap_local)
121 dst_ops->unmap_local(dst_iter, &dst_map);
122 }
123}
124EXPORT_SYMBOL(ttm_move_memcpy);
125
126/**
127 * ttm_bo_move_memcpy
128 *
129 * @bo: A pointer to a struct ttm_buffer_object.
130 * @ctx: operation context
131 * @dst_mem: struct ttm_resource indicating where to move.
132 *
133 * Fallback move function for a mappable buffer object in mappable memory.
134 * The function will, if successful,
135 * free any old aperture space, and set (@new_mem)->mm_node to NULL,
136 * and update the (@bo)->mem placement flags. If unsuccessful, the old
137 * data remains untouched, and it's up to the caller to free the
138 * memory space indicated by @new_mem.
139 * Returns:
140 * !0: Failure.
141 */
142int ttm_bo_move_memcpy(struct ttm_buffer_object *bo,
143 struct ttm_operation_ctx *ctx,
144 struct ttm_resource *dst_mem)
145{
146 struct ttm_device *bdev = bo->bdev;
147 struct ttm_resource_manager *dst_man =
148 ttm_manager_type(bo->bdev, dst_mem->mem_type);
149 struct ttm_tt *ttm = bo->ttm;
150 struct ttm_resource *src_mem = bo->resource;
151 struct ttm_resource_manager *src_man;
152 union {
153 struct ttm_kmap_iter_tt tt;
154 struct ttm_kmap_iter_linear_io io;
155 } _dst_iter, _src_iter;
156 struct ttm_kmap_iter *dst_iter, *src_iter;
157 bool clear;
158 int ret = 0;
159
160 if (WARN_ON(!src_mem))
161 return -EINVAL;
162
163 src_man = ttm_manager_type(bdev, src_mem->mem_type);
164 if (ttm && ((ttm->page_flags & TTM_TT_FLAG_SWAPPED) ||
165 dst_man->use_tt)) {
166 ret = ttm_tt_populate(bdev, ttm, ctx);
167 if (ret)
168 return ret;
169 }
170
171 dst_iter = ttm_kmap_iter_linear_io_init(&_dst_iter.io, bdev, dst_mem);
172 if (PTR_ERR(dst_iter) == -EINVAL && dst_man->use_tt)
173 dst_iter = ttm_kmap_iter_tt_init(&_dst_iter.tt, bo->ttm);
174 if (IS_ERR(dst_iter))
175 return PTR_ERR(dst_iter);
176
177 src_iter = ttm_kmap_iter_linear_io_init(&_src_iter.io, bdev, src_mem);
178 if (PTR_ERR(src_iter) == -EINVAL && src_man->use_tt)
179 src_iter = ttm_kmap_iter_tt_init(&_src_iter.tt, bo->ttm);
180 if (IS_ERR(src_iter)) {
181 ret = PTR_ERR(src_iter);
182 goto out_src_iter;
183 }
184
185 clear = src_iter->ops->maps_tt && (!ttm || !ttm_tt_is_populated(ttm));
186 if (!(clear && ttm && !(ttm->page_flags & TTM_TT_FLAG_ZERO_ALLOC)))
187 ttm_move_memcpy(clear, PFN_UP(dst_mem->size), dst_iter, src_iter);
188
189 if (!src_iter->ops->maps_tt)
190 ttm_kmap_iter_linear_io_fini(&_src_iter.io, bdev, src_mem);
191 ttm_bo_move_sync_cleanup(bo, dst_mem);
192
193out_src_iter:
194 if (!dst_iter->ops->maps_tt)
195 ttm_kmap_iter_linear_io_fini(&_dst_iter.io, bdev, dst_mem);
196
197 return ret;
198}
199EXPORT_SYMBOL(ttm_bo_move_memcpy);
200
201static void ttm_transfered_destroy(struct ttm_buffer_object *bo)
202{
203 struct ttm_transfer_obj *fbo;
204
205 fbo = container_of(bo, struct ttm_transfer_obj, base);
206 dma_resv_fini(&fbo->base.base._resv);
207 ttm_bo_put(fbo->bo);
208 kfree(fbo);
209}
210
211/**
212 * ttm_buffer_object_transfer
213 *
214 * @bo: A pointer to a struct ttm_buffer_object.
215 * @new_obj: A pointer to a pointer to a newly created ttm_buffer_object,
216 * holding the data of @bo with the old placement.
217 *
218 * This is a utility function that may be called after an accelerated move
219 * has been scheduled. A new buffer object is created as a placeholder for
220 * the old data while it's being copied. When that buffer object is idle,
221 * it can be destroyed, releasing the space of the old placement.
222 * Returns:
223 * !0: Failure.
224 */
225
226static int ttm_buffer_object_transfer(struct ttm_buffer_object *bo,
227 struct ttm_buffer_object **new_obj)
228{
229 struct ttm_transfer_obj *fbo;
230 int ret;
231
232 fbo = kmalloc(sizeof(*fbo), GFP_KERNEL);
233 if (!fbo)
234 return -ENOMEM;
235
236 fbo->base = *bo;
237
238 /**
239 * Fix up members that we shouldn't copy directly:
240 * TODO: Explicit member copy would probably be better here.
241 */
242
243 atomic_inc(&ttm_glob.bo_count);
244 drm_vma_node_reset(&fbo->base.base.vma_node);
245
246 kref_init(&fbo->base.kref);
247 fbo->base.destroy = &ttm_transfered_destroy;
248 fbo->base.pin_count = 0;
249 if (bo->type != ttm_bo_type_sg)
250 fbo->base.base.resv = &fbo->base.base._resv;
251
252 dma_resv_init(&fbo->base.base._resv);
253 fbo->base.base.dev = NULL;
254 ret = dma_resv_trylock(&fbo->base.base._resv);
255 WARN_ON(!ret);
256
257 if (fbo->base.resource) {
258 ttm_resource_set_bo(fbo->base.resource, &fbo->base);
259 bo->resource = NULL;
260 ttm_bo_set_bulk_move(&fbo->base, NULL);
261 } else {
262 fbo->base.bulk_move = NULL;
263 }
264
265 ret = dma_resv_reserve_fences(&fbo->base.base._resv, 1);
266 if (ret) {
267 kfree(fbo);
268 return ret;
269 }
270
271 ttm_bo_get(bo);
272 fbo->bo = bo;
273
274 ttm_bo_move_to_lru_tail_unlocked(&fbo->base);
275
276 *new_obj = &fbo->base;
277 return 0;
278}
279
280/**
281 * ttm_io_prot
282 *
283 * @bo: ttm buffer object
284 * @res: ttm resource object
285 * @tmp: Page protection flag for a normal, cached mapping.
286 *
287 * Utility function that returns the pgprot_t that should be used for
288 * setting up a PTE with the caching model indicated by @c_state.
289 */
290pgprot_t ttm_io_prot(struct ttm_buffer_object *bo, struct ttm_resource *res,
291 pgprot_t tmp)
292{
293 struct ttm_resource_manager *man;
294 enum ttm_caching caching;
295
296 man = ttm_manager_type(bo->bdev, res->mem_type);
297 caching = man->use_tt ? bo->ttm->caching : res->bus.caching;
298
299 return ttm_prot_from_caching(caching, tmp);
300}
301EXPORT_SYMBOL(ttm_io_prot);
302
303static int ttm_bo_ioremap(struct ttm_buffer_object *bo,
304 unsigned long offset,
305 unsigned long size,
306 struct ttm_bo_kmap_obj *map)
307{
308 struct ttm_resource *mem = bo->resource;
309
310 if (bo->resource->bus.addr) {
311 map->bo_kmap_type = ttm_bo_map_premapped;
312 map->virtual = ((u8 *)bo->resource->bus.addr) + offset;
313 } else {
314 resource_size_t res = bo->resource->bus.offset + offset;
315
316 map->bo_kmap_type = ttm_bo_map_iomap;
317 if (mem->bus.caching == ttm_write_combined)
318 map->virtual = ioremap_wc(res, size);
319#ifdef CONFIG_X86
320 else if (mem->bus.caching == ttm_cached)
321 map->virtual = ioremap_cache(res, size);
322#endif
323 else
324 map->virtual = ioremap(res, size);
325 }
326 return (!map->virtual) ? -ENOMEM : 0;
327}
328
329static int ttm_bo_kmap_ttm(struct ttm_buffer_object *bo,
330 unsigned long start_page,
331 unsigned long num_pages,
332 struct ttm_bo_kmap_obj *map)
333{
334 struct ttm_resource *mem = bo->resource;
335 struct ttm_operation_ctx ctx = {
336 .interruptible = false,
337 .no_wait_gpu = false
338 };
339 struct ttm_tt *ttm = bo->ttm;
340 pgprot_t prot;
341 int ret;
342
343 BUG_ON(!ttm);
344
345 ret = ttm_tt_populate(bo->bdev, ttm, &ctx);
346 if (ret)
347 return ret;
348
349 if (num_pages == 1 && ttm->caching == ttm_cached) {
350 /*
351 * We're mapping a single page, and the desired
352 * page protection is consistent with the bo.
353 */
354
355 map->bo_kmap_type = ttm_bo_map_kmap;
356 map->page = ttm->pages[start_page];
357 map->virtual = kmap(map->page);
358 } else {
359 /*
360 * We need to use vmap to get the desired page protection
361 * or to make the buffer object look contiguous.
362 */
363 prot = ttm_io_prot(bo, mem, PAGE_KERNEL);
364 map->bo_kmap_type = ttm_bo_map_vmap;
365 map->virtual = vmap(ttm->pages + start_page, num_pages,
366 0, prot);
367 }
368 return (!map->virtual) ? -ENOMEM : 0;
369}
370
371/**
372 * ttm_bo_kmap
373 *
374 * @bo: The buffer object.
375 * @start_page: The first page to map.
376 * @num_pages: Number of pages to map.
377 * @map: pointer to a struct ttm_bo_kmap_obj representing the map.
378 *
379 * Sets up a kernel virtual mapping, using ioremap, vmap or kmap to the
380 * data in the buffer object. The ttm_kmap_obj_virtual function can then be
381 * used to obtain a virtual address to the data.
382 *
383 * Returns
384 * -ENOMEM: Out of memory.
385 * -EINVAL: Invalid range.
386 */
387int ttm_bo_kmap(struct ttm_buffer_object *bo,
388 unsigned long start_page, unsigned long num_pages,
389 struct ttm_bo_kmap_obj *map)
390{
391 unsigned long offset, size;
392 int ret;
393
394 map->virtual = NULL;
395 map->bo = bo;
396 if (num_pages > PFN_UP(bo->resource->size))
397 return -EINVAL;
398 if ((start_page + num_pages) > PFN_UP(bo->resource->size))
399 return -EINVAL;
400
401 ret = ttm_mem_io_reserve(bo->bdev, bo->resource);
402 if (ret)
403 return ret;
404 if (!bo->resource->bus.is_iomem) {
405 return ttm_bo_kmap_ttm(bo, start_page, num_pages, map);
406 } else {
407 offset = start_page << PAGE_SHIFT;
408 size = num_pages << PAGE_SHIFT;
409 return ttm_bo_ioremap(bo, offset, size, map);
410 }
411}
412EXPORT_SYMBOL(ttm_bo_kmap);
413
414/**
415 * ttm_bo_kunmap
416 *
417 * @map: Object describing the map to unmap.
418 *
419 * Unmaps a kernel map set up by ttm_bo_kmap.
420 */
421void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map)
422{
423 if (!map->virtual)
424 return;
425 switch (map->bo_kmap_type) {
426 case ttm_bo_map_iomap:
427 iounmap(map->virtual);
428 break;
429 case ttm_bo_map_vmap:
430 vunmap(map->virtual);
431 break;
432 case ttm_bo_map_kmap:
433 kunmap(map->page);
434 break;
435 case ttm_bo_map_premapped:
436 break;
437 default:
438 BUG();
439 }
440 ttm_mem_io_free(map->bo->bdev, map->bo->resource);
441 map->virtual = NULL;
442 map->page = NULL;
443}
444EXPORT_SYMBOL(ttm_bo_kunmap);
445
446/**
447 * ttm_bo_vmap
448 *
449 * @bo: The buffer object.
450 * @map: pointer to a struct iosys_map representing the map.
451 *
452 * Sets up a kernel virtual mapping, using ioremap or vmap to the
453 * data in the buffer object. The parameter @map returns the virtual
454 * address as struct iosys_map. Unmap the buffer with ttm_bo_vunmap().
455 *
456 * Returns
457 * -ENOMEM: Out of memory.
458 * -EINVAL: Invalid range.
459 */
460int ttm_bo_vmap(struct ttm_buffer_object *bo, struct iosys_map *map)
461{
462 struct ttm_resource *mem = bo->resource;
463 int ret;
464
465 dma_resv_assert_held(bo->base.resv);
466
467 ret = ttm_mem_io_reserve(bo->bdev, mem);
468 if (ret)
469 return ret;
470
471 if (mem->bus.is_iomem) {
472 void __iomem *vaddr_iomem;
473
474 if (mem->bus.addr)
475 vaddr_iomem = (void __iomem *)mem->bus.addr;
476 else if (mem->bus.caching == ttm_write_combined)
477 vaddr_iomem = ioremap_wc(mem->bus.offset,
478 bo->base.size);
479#ifdef CONFIG_X86
480 else if (mem->bus.caching == ttm_cached)
481 vaddr_iomem = ioremap_cache(mem->bus.offset,
482 bo->base.size);
483#endif
484 else
485 vaddr_iomem = ioremap(mem->bus.offset, bo->base.size);
486
487 if (!vaddr_iomem)
488 return -ENOMEM;
489
490 iosys_map_set_vaddr_iomem(map, vaddr_iomem);
491
492 } else {
493 struct ttm_operation_ctx ctx = {
494 .interruptible = false,
495 .no_wait_gpu = false
496 };
497 struct ttm_tt *ttm = bo->ttm;
498 pgprot_t prot;
499 void *vaddr;
500
501 ret = ttm_tt_populate(bo->bdev, ttm, &ctx);
502 if (ret)
503 return ret;
504
505 /*
506 * We need to use vmap to get the desired page protection
507 * or to make the buffer object look contiguous.
508 */
509 prot = ttm_io_prot(bo, mem, PAGE_KERNEL);
510 vaddr = vmap(ttm->pages, ttm->num_pages, 0, prot);
511 if (!vaddr)
512 return -ENOMEM;
513
514 iosys_map_set_vaddr(map, vaddr);
515 }
516
517 return 0;
518}
519EXPORT_SYMBOL(ttm_bo_vmap);
520
521/**
522 * ttm_bo_vunmap
523 *
524 * @bo: The buffer object.
525 * @map: Object describing the map to unmap.
526 *
527 * Unmaps a kernel map set up by ttm_bo_vmap().
528 */
529void ttm_bo_vunmap(struct ttm_buffer_object *bo, struct iosys_map *map)
530{
531 struct ttm_resource *mem = bo->resource;
532
533 dma_resv_assert_held(bo->base.resv);
534
535 if (iosys_map_is_null(map))
536 return;
537
538 if (!map->is_iomem)
539 vunmap(map->vaddr);
540 else if (!mem->bus.addr)
541 iounmap(map->vaddr_iomem);
542 iosys_map_clear(map);
543
544 ttm_mem_io_free(bo->bdev, bo->resource);
545}
546EXPORT_SYMBOL(ttm_bo_vunmap);
547
548static int ttm_bo_wait_free_node(struct ttm_buffer_object *bo,
549 bool dst_use_tt)
550{
551 long ret;
552
553 ret = dma_resv_wait_timeout(bo->base.resv, DMA_RESV_USAGE_BOOKKEEP,
554 false, 15 * HZ);
555 if (ret == 0)
556 return -EBUSY;
557 if (ret < 0)
558 return ret;
559
560 if (!dst_use_tt)
561 ttm_bo_tt_destroy(bo);
562 ttm_resource_free(bo, &bo->resource);
563 return 0;
564}
565
566static int ttm_bo_move_to_ghost(struct ttm_buffer_object *bo,
567 struct dma_fence *fence,
568 bool dst_use_tt)
569{
570 struct ttm_buffer_object *ghost_obj;
571 int ret;
572
573 /**
574 * This should help pipeline ordinary buffer moves.
575 *
576 * Hang old buffer memory on a new buffer object,
577 * and leave it to be released when the GPU
578 * operation has completed.
579 */
580
581 ret = ttm_buffer_object_transfer(bo, &ghost_obj);
582 if (ret)
583 return ret;
584
585 dma_resv_add_fence(&ghost_obj->base._resv, fence,
586 DMA_RESV_USAGE_KERNEL);
587
588 /**
589 * If we're not moving to fixed memory, the TTM object
590 * needs to stay alive. Otherwhise hang it on the ghost
591 * bo to be unbound and destroyed.
592 */
593
594 if (dst_use_tt)
595 ghost_obj->ttm = NULL;
596 else
597 bo->ttm = NULL;
598
599 dma_resv_unlock(&ghost_obj->base._resv);
600 ttm_bo_put(ghost_obj);
601 return 0;
602}
603
604static void ttm_bo_move_pipeline_evict(struct ttm_buffer_object *bo,
605 struct dma_fence *fence)
606{
607 struct ttm_device *bdev = bo->bdev;
608 struct ttm_resource_manager *from;
609
610 from = ttm_manager_type(bdev, bo->resource->mem_type);
611
612 /**
613 * BO doesn't have a TTM we need to bind/unbind. Just remember
614 * this eviction and free up the allocation
615 */
616 spin_lock(&from->move_lock);
617 if (!from->move || dma_fence_is_later(fence, from->move)) {
618 dma_fence_put(from->move);
619 from->move = dma_fence_get(fence);
620 }
621 spin_unlock(&from->move_lock);
622
623 ttm_resource_free(bo, &bo->resource);
624}
625
626/**
627 * ttm_bo_move_accel_cleanup - cleanup helper for hw copies
628 *
629 * @bo: A pointer to a struct ttm_buffer_object.
630 * @fence: A fence object that signals when moving is complete.
631 * @evict: This is an evict move. Don't return until the buffer is idle.
632 * @pipeline: evictions are to be pipelined.
633 * @new_mem: struct ttm_resource indicating where to move.
634 *
635 * Accelerated move function to be called when an accelerated move
636 * has been scheduled. The function will create a new temporary buffer object
637 * representing the old placement, and put the sync object on both buffer
638 * objects. After that the newly created buffer object is unref'd to be
639 * destroyed when the move is complete. This will help pipeline
640 * buffer moves.
641 */
642int ttm_bo_move_accel_cleanup(struct ttm_buffer_object *bo,
643 struct dma_fence *fence,
644 bool evict,
645 bool pipeline,
646 struct ttm_resource *new_mem)
647{
648 struct ttm_device *bdev = bo->bdev;
649 struct ttm_resource_manager *from = ttm_manager_type(bdev, bo->resource->mem_type);
650 struct ttm_resource_manager *man = ttm_manager_type(bdev, new_mem->mem_type);
651 int ret = 0;
652
653 dma_resv_add_fence(bo->base.resv, fence, DMA_RESV_USAGE_KERNEL);
654 if (!evict)
655 ret = ttm_bo_move_to_ghost(bo, fence, man->use_tt);
656 else if (!from->use_tt && pipeline)
657 ttm_bo_move_pipeline_evict(bo, fence);
658 else
659 ret = ttm_bo_wait_free_node(bo, man->use_tt);
660
661 if (ret)
662 return ret;
663
664 ttm_bo_assign_mem(bo, new_mem);
665
666 return 0;
667}
668EXPORT_SYMBOL(ttm_bo_move_accel_cleanup);
669
670/**
671 * ttm_bo_move_sync_cleanup - cleanup by waiting for the move to finish
672 *
673 * @bo: A pointer to a struct ttm_buffer_object.
674 * @new_mem: struct ttm_resource indicating where to move.
675 *
676 * Special case of ttm_bo_move_accel_cleanup where the bo is guaranteed
677 * by the caller to be idle. Typically used after memcpy buffer moves.
678 */
679void ttm_bo_move_sync_cleanup(struct ttm_buffer_object *bo,
680 struct ttm_resource *new_mem)
681{
682 struct ttm_device *bdev = bo->bdev;
683 struct ttm_resource_manager *man = ttm_manager_type(bdev, new_mem->mem_type);
684 int ret;
685
686 ret = ttm_bo_wait_free_node(bo, man->use_tt);
687 if (WARN_ON(ret))
688 return;
689
690 ttm_bo_assign_mem(bo, new_mem);
691}
692EXPORT_SYMBOL(ttm_bo_move_sync_cleanup);
693
694/**
695 * ttm_bo_pipeline_gutting - purge the contents of a bo
696 * @bo: The buffer object
697 *
698 * Purge the contents of a bo, async if the bo is not idle.
699 * After a successful call, the bo is left unpopulated in
700 * system placement. The function may wait uninterruptible
701 * for idle on OOM.
702 *
703 * Return: 0 if successful, negative error code on failure.
704 */
705int ttm_bo_pipeline_gutting(struct ttm_buffer_object *bo)
706{
707 struct ttm_buffer_object *ghost;
708 struct ttm_tt *ttm;
709 int ret;
710
711 /* If already idle, no need for ghost object dance. */
712 if (dma_resv_test_signaled(bo->base.resv, DMA_RESV_USAGE_BOOKKEEP)) {
713 if (!bo->ttm) {
714 /* See comment below about clearing. */
715 ret = ttm_tt_create(bo, true);
716 if (ret)
717 return ret;
718 } else {
719 ttm_tt_unpopulate(bo->bdev, bo->ttm);
720 if (bo->type == ttm_bo_type_device)
721 ttm_tt_mark_for_clear(bo->ttm);
722 }
723 ttm_resource_free(bo, &bo->resource);
724 return 0;
725 }
726
727 /*
728 * We need an unpopulated ttm_tt after giving our current one,
729 * if any, to the ghost object. And we can't afford to fail
730 * creating one *after* the operation. If the bo subsequently gets
731 * resurrected, make sure it's cleared (if ttm_bo_type_device)
732 * to avoid leaking sensitive information to user-space.
733 */
734
735 ttm = bo->ttm;
736 bo->ttm = NULL;
737 ret = ttm_tt_create(bo, true);
738 swap(bo->ttm, ttm);
739 if (ret)
740 return ret;
741
742 ret = ttm_buffer_object_transfer(bo, &ghost);
743 if (ret)
744 goto error_destroy_tt;
745
746 ret = dma_resv_copy_fences(&ghost->base._resv, bo->base.resv);
747 /* Last resort, wait for the BO to be idle when we are OOM */
748 if (ret) {
749 dma_resv_wait_timeout(bo->base.resv, DMA_RESV_USAGE_BOOKKEEP,
750 false, MAX_SCHEDULE_TIMEOUT);
751 }
752
753 dma_resv_unlock(&ghost->base._resv);
754 ttm_bo_put(ghost);
755 bo->ttm = ttm;
756 return 0;
757
758error_destroy_tt:
759 ttm_tt_destroy(bo->bdev, ttm);
760 return ret;
761}
1/* SPDX-License-Identifier: GPL-2.0 OR MIT */
2/**************************************************************************
3 *
4 * Copyright (c) 2007-2009 VMware, Inc., Palo Alto, CA., USA
5 * All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the
9 * "Software"), to deal in the Software without restriction, including
10 * without limitation the rights to use, copy, modify, merge, publish,
11 * distribute, sub license, and/or sell copies of the Software, and to
12 * permit persons to whom the Software is furnished to do so, subject to
13 * the following conditions:
14 *
15 * The above copyright notice and this permission notice (including the
16 * next paragraph) shall be included in all copies or substantial portions
17 * of the Software.
18 *
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
22 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
23 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
24 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
25 * USE OR OTHER DEALINGS IN THE SOFTWARE.
26 *
27 **************************************************************************/
28/*
29 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
30 */
31
32#include <drm/ttm/ttm_bo_driver.h>
33#include <drm/ttm/ttm_placement.h>
34#include <drm/drm_cache.h>
35#include <drm/drm_vma_manager.h>
36#include <linux/dma-buf-map.h>
37#include <linux/io.h>
38#include <linux/highmem.h>
39#include <linux/wait.h>
40#include <linux/slab.h>
41#include <linux/vmalloc.h>
42#include <linux/module.h>
43#include <linux/dma-resv.h>
44
45struct ttm_transfer_obj {
46 struct ttm_buffer_object base;
47 struct ttm_buffer_object *bo;
48};
49
50int ttm_mem_io_reserve(struct ttm_device *bdev,
51 struct ttm_resource *mem)
52{
53 if (mem->bus.offset || mem->bus.addr)
54 return 0;
55
56 mem->bus.is_iomem = false;
57 if (!bdev->funcs->io_mem_reserve)
58 return 0;
59
60 return bdev->funcs->io_mem_reserve(bdev, mem);
61}
62
63void ttm_mem_io_free(struct ttm_device *bdev,
64 struct ttm_resource *mem)
65{
66 if (!mem)
67 return;
68
69 if (!mem->bus.offset && !mem->bus.addr)
70 return;
71
72 if (bdev->funcs->io_mem_free)
73 bdev->funcs->io_mem_free(bdev, mem);
74
75 mem->bus.offset = 0;
76 mem->bus.addr = NULL;
77}
78
79/**
80 * ttm_move_memcpy - Helper to perform a memcpy ttm move operation.
81 * @bo: The struct ttm_buffer_object.
82 * @new_mem: The struct ttm_resource we're moving to (copy destination).
83 * @new_iter: A struct ttm_kmap_iter representing the destination resource.
84 * @src_iter: A struct ttm_kmap_iter representing the source resource.
85 *
86 * This function is intended to be able to move out async under a
87 * dma-fence if desired.
88 */
89void ttm_move_memcpy(struct ttm_buffer_object *bo,
90 u32 num_pages,
91 struct ttm_kmap_iter *dst_iter,
92 struct ttm_kmap_iter *src_iter)
93{
94 const struct ttm_kmap_iter_ops *dst_ops = dst_iter->ops;
95 const struct ttm_kmap_iter_ops *src_ops = src_iter->ops;
96 struct ttm_tt *ttm = bo->ttm;
97 struct dma_buf_map src_map, dst_map;
98 pgoff_t i;
99
100 /* Single TTM move. NOP */
101 if (dst_ops->maps_tt && src_ops->maps_tt)
102 return;
103
104 /* Don't move nonexistent data. Clear destination instead. */
105 if (src_ops->maps_tt && (!ttm || !ttm_tt_is_populated(ttm))) {
106 if (ttm && !(ttm->page_flags & TTM_PAGE_FLAG_ZERO_ALLOC))
107 return;
108
109 for (i = 0; i < num_pages; ++i) {
110 dst_ops->map_local(dst_iter, &dst_map, i);
111 if (dst_map.is_iomem)
112 memset_io(dst_map.vaddr_iomem, 0, PAGE_SIZE);
113 else
114 memset(dst_map.vaddr, 0, PAGE_SIZE);
115 if (dst_ops->unmap_local)
116 dst_ops->unmap_local(dst_iter, &dst_map);
117 }
118 return;
119 }
120
121 for (i = 0; i < num_pages; ++i) {
122 dst_ops->map_local(dst_iter, &dst_map, i);
123 src_ops->map_local(src_iter, &src_map, i);
124
125 drm_memcpy_from_wc(&dst_map, &src_map, PAGE_SIZE);
126
127 if (src_ops->unmap_local)
128 src_ops->unmap_local(src_iter, &src_map);
129 if (dst_ops->unmap_local)
130 dst_ops->unmap_local(dst_iter, &dst_map);
131 }
132}
133EXPORT_SYMBOL(ttm_move_memcpy);
134
135int ttm_bo_move_memcpy(struct ttm_buffer_object *bo,
136 struct ttm_operation_ctx *ctx,
137 struct ttm_resource *dst_mem)
138{
139 struct ttm_device *bdev = bo->bdev;
140 struct ttm_resource_manager *dst_man =
141 ttm_manager_type(bo->bdev, dst_mem->mem_type);
142 struct ttm_tt *ttm = bo->ttm;
143 struct ttm_resource *src_mem = bo->resource;
144 struct ttm_resource_manager *src_man =
145 ttm_manager_type(bdev, src_mem->mem_type);
146 union {
147 struct ttm_kmap_iter_tt tt;
148 struct ttm_kmap_iter_linear_io io;
149 } _dst_iter, _src_iter;
150 struct ttm_kmap_iter *dst_iter, *src_iter;
151 int ret = 0;
152
153 if (ttm && ((ttm->page_flags & TTM_PAGE_FLAG_SWAPPED) ||
154 dst_man->use_tt)) {
155 ret = ttm_tt_populate(bdev, ttm, ctx);
156 if (ret)
157 return ret;
158 }
159
160 dst_iter = ttm_kmap_iter_linear_io_init(&_dst_iter.io, bdev, dst_mem);
161 if (PTR_ERR(dst_iter) == -EINVAL && dst_man->use_tt)
162 dst_iter = ttm_kmap_iter_tt_init(&_dst_iter.tt, bo->ttm);
163 if (IS_ERR(dst_iter))
164 return PTR_ERR(dst_iter);
165
166 src_iter = ttm_kmap_iter_linear_io_init(&_src_iter.io, bdev, src_mem);
167 if (PTR_ERR(src_iter) == -EINVAL && src_man->use_tt)
168 src_iter = ttm_kmap_iter_tt_init(&_src_iter.tt, bo->ttm);
169 if (IS_ERR(src_iter)) {
170 ret = PTR_ERR(src_iter);
171 goto out_src_iter;
172 }
173
174 ttm_move_memcpy(bo, dst_mem->num_pages, dst_iter, src_iter);
175
176 if (!src_iter->ops->maps_tt)
177 ttm_kmap_iter_linear_io_fini(&_src_iter.io, bdev, src_mem);
178 ttm_bo_move_sync_cleanup(bo, dst_mem);
179
180out_src_iter:
181 if (!dst_iter->ops->maps_tt)
182 ttm_kmap_iter_linear_io_fini(&_dst_iter.io, bdev, dst_mem);
183
184 return ret;
185}
186EXPORT_SYMBOL(ttm_bo_move_memcpy);
187
188static void ttm_transfered_destroy(struct ttm_buffer_object *bo)
189{
190 struct ttm_transfer_obj *fbo;
191
192 fbo = container_of(bo, struct ttm_transfer_obj, base);
193 ttm_bo_put(fbo->bo);
194 kfree(fbo);
195}
196
197/**
198 * ttm_buffer_object_transfer
199 *
200 * @bo: A pointer to a struct ttm_buffer_object.
201 * @new_obj: A pointer to a pointer to a newly created ttm_buffer_object,
202 * holding the data of @bo with the old placement.
203 *
204 * This is a utility function that may be called after an accelerated move
205 * has been scheduled. A new buffer object is created as a placeholder for
206 * the old data while it's being copied. When that buffer object is idle,
207 * it can be destroyed, releasing the space of the old placement.
208 * Returns:
209 * !0: Failure.
210 */
211
212static int ttm_buffer_object_transfer(struct ttm_buffer_object *bo,
213 struct ttm_buffer_object **new_obj)
214{
215 struct ttm_transfer_obj *fbo;
216 int ret;
217
218 fbo = kmalloc(sizeof(*fbo), GFP_KERNEL);
219 if (!fbo)
220 return -ENOMEM;
221
222 fbo->base = *bo;
223
224 ttm_bo_get(bo);
225 fbo->bo = bo;
226
227 /**
228 * Fix up members that we shouldn't copy directly:
229 * TODO: Explicit member copy would probably be better here.
230 */
231
232 atomic_inc(&ttm_glob.bo_count);
233 INIT_LIST_HEAD(&fbo->base.ddestroy);
234 INIT_LIST_HEAD(&fbo->base.lru);
235 fbo->base.moving = NULL;
236 drm_vma_node_reset(&fbo->base.base.vma_node);
237
238 kref_init(&fbo->base.kref);
239 fbo->base.destroy = &ttm_transfered_destroy;
240 fbo->base.pin_count = 0;
241 if (bo->type != ttm_bo_type_sg)
242 fbo->base.base.resv = &fbo->base.base._resv;
243
244 dma_resv_init(&fbo->base.base._resv);
245 fbo->base.base.dev = NULL;
246 ret = dma_resv_trylock(&fbo->base.base._resv);
247 WARN_ON(!ret);
248
249 ttm_bo_move_to_lru_tail_unlocked(&fbo->base);
250
251 *new_obj = &fbo->base;
252 return 0;
253}
254
255pgprot_t ttm_io_prot(struct ttm_buffer_object *bo, struct ttm_resource *res,
256 pgprot_t tmp)
257{
258 struct ttm_resource_manager *man;
259 enum ttm_caching caching;
260
261 man = ttm_manager_type(bo->bdev, res->mem_type);
262 caching = man->use_tt ? bo->ttm->caching : res->bus.caching;
263
264 return ttm_prot_from_caching(caching, tmp);
265}
266EXPORT_SYMBOL(ttm_io_prot);
267
268static int ttm_bo_ioremap(struct ttm_buffer_object *bo,
269 unsigned long offset,
270 unsigned long size,
271 struct ttm_bo_kmap_obj *map)
272{
273 struct ttm_resource *mem = bo->resource;
274
275 if (bo->resource->bus.addr) {
276 map->bo_kmap_type = ttm_bo_map_premapped;
277 map->virtual = ((u8 *)bo->resource->bus.addr) + offset;
278 } else {
279 resource_size_t res = bo->resource->bus.offset + offset;
280
281 map->bo_kmap_type = ttm_bo_map_iomap;
282 if (mem->bus.caching == ttm_write_combined)
283 map->virtual = ioremap_wc(res, size);
284#ifdef CONFIG_X86
285 else if (mem->bus.caching == ttm_cached)
286 map->virtual = ioremap_cache(res, size);
287#endif
288 else
289 map->virtual = ioremap(res, size);
290 }
291 return (!map->virtual) ? -ENOMEM : 0;
292}
293
294static int ttm_bo_kmap_ttm(struct ttm_buffer_object *bo,
295 unsigned long start_page,
296 unsigned long num_pages,
297 struct ttm_bo_kmap_obj *map)
298{
299 struct ttm_resource *mem = bo->resource;
300 struct ttm_operation_ctx ctx = {
301 .interruptible = false,
302 .no_wait_gpu = false
303 };
304 struct ttm_tt *ttm = bo->ttm;
305 pgprot_t prot;
306 int ret;
307
308 BUG_ON(!ttm);
309
310 ret = ttm_tt_populate(bo->bdev, ttm, &ctx);
311 if (ret)
312 return ret;
313
314 if (num_pages == 1 && ttm->caching == ttm_cached) {
315 /*
316 * We're mapping a single page, and the desired
317 * page protection is consistent with the bo.
318 */
319
320 map->bo_kmap_type = ttm_bo_map_kmap;
321 map->page = ttm->pages[start_page];
322 map->virtual = kmap(map->page);
323 } else {
324 /*
325 * We need to use vmap to get the desired page protection
326 * or to make the buffer object look contiguous.
327 */
328 prot = ttm_io_prot(bo, mem, PAGE_KERNEL);
329 map->bo_kmap_type = ttm_bo_map_vmap;
330 map->virtual = vmap(ttm->pages + start_page, num_pages,
331 0, prot);
332 }
333 return (!map->virtual) ? -ENOMEM : 0;
334}
335
336int ttm_bo_kmap(struct ttm_buffer_object *bo,
337 unsigned long start_page, unsigned long num_pages,
338 struct ttm_bo_kmap_obj *map)
339{
340 unsigned long offset, size;
341 int ret;
342
343 map->virtual = NULL;
344 map->bo = bo;
345 if (num_pages > bo->resource->num_pages)
346 return -EINVAL;
347 if ((start_page + num_pages) > bo->resource->num_pages)
348 return -EINVAL;
349
350 ret = ttm_mem_io_reserve(bo->bdev, bo->resource);
351 if (ret)
352 return ret;
353 if (!bo->resource->bus.is_iomem) {
354 return ttm_bo_kmap_ttm(bo, start_page, num_pages, map);
355 } else {
356 offset = start_page << PAGE_SHIFT;
357 size = num_pages << PAGE_SHIFT;
358 return ttm_bo_ioremap(bo, offset, size, map);
359 }
360}
361EXPORT_SYMBOL(ttm_bo_kmap);
362
363void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map)
364{
365 if (!map->virtual)
366 return;
367 switch (map->bo_kmap_type) {
368 case ttm_bo_map_iomap:
369 iounmap(map->virtual);
370 break;
371 case ttm_bo_map_vmap:
372 vunmap(map->virtual);
373 break;
374 case ttm_bo_map_kmap:
375 kunmap(map->page);
376 break;
377 case ttm_bo_map_premapped:
378 break;
379 default:
380 BUG();
381 }
382 ttm_mem_io_free(map->bo->bdev, map->bo->resource);
383 map->virtual = NULL;
384 map->page = NULL;
385}
386EXPORT_SYMBOL(ttm_bo_kunmap);
387
388int ttm_bo_vmap(struct ttm_buffer_object *bo, struct dma_buf_map *map)
389{
390 struct ttm_resource *mem = bo->resource;
391 int ret;
392
393 ret = ttm_mem_io_reserve(bo->bdev, mem);
394 if (ret)
395 return ret;
396
397 if (mem->bus.is_iomem) {
398 void __iomem *vaddr_iomem;
399
400 if (mem->bus.addr)
401 vaddr_iomem = (void __iomem *)mem->bus.addr;
402 else if (mem->bus.caching == ttm_write_combined)
403 vaddr_iomem = ioremap_wc(mem->bus.offset,
404 bo->base.size);
405#ifdef CONFIG_X86
406 else if (mem->bus.caching == ttm_cached)
407 vaddr_iomem = ioremap_cache(mem->bus.offset,
408 bo->base.size);
409#endif
410 else
411 vaddr_iomem = ioremap(mem->bus.offset, bo->base.size);
412
413 if (!vaddr_iomem)
414 return -ENOMEM;
415
416 dma_buf_map_set_vaddr_iomem(map, vaddr_iomem);
417
418 } else {
419 struct ttm_operation_ctx ctx = {
420 .interruptible = false,
421 .no_wait_gpu = false
422 };
423 struct ttm_tt *ttm = bo->ttm;
424 pgprot_t prot;
425 void *vaddr;
426
427 ret = ttm_tt_populate(bo->bdev, ttm, &ctx);
428 if (ret)
429 return ret;
430
431 /*
432 * We need to use vmap to get the desired page protection
433 * or to make the buffer object look contiguous.
434 */
435 prot = ttm_io_prot(bo, mem, PAGE_KERNEL);
436 vaddr = vmap(ttm->pages, ttm->num_pages, 0, prot);
437 if (!vaddr)
438 return -ENOMEM;
439
440 dma_buf_map_set_vaddr(map, vaddr);
441 }
442
443 return 0;
444}
445EXPORT_SYMBOL(ttm_bo_vmap);
446
447void ttm_bo_vunmap(struct ttm_buffer_object *bo, struct dma_buf_map *map)
448{
449 struct ttm_resource *mem = bo->resource;
450
451 if (dma_buf_map_is_null(map))
452 return;
453
454 if (!map->is_iomem)
455 vunmap(map->vaddr);
456 else if (!mem->bus.addr)
457 iounmap(map->vaddr_iomem);
458 dma_buf_map_clear(map);
459
460 ttm_mem_io_free(bo->bdev, bo->resource);
461}
462EXPORT_SYMBOL(ttm_bo_vunmap);
463
464static int ttm_bo_wait_free_node(struct ttm_buffer_object *bo,
465 bool dst_use_tt)
466{
467 int ret;
468 ret = ttm_bo_wait(bo, false, false);
469 if (ret)
470 return ret;
471
472 if (!dst_use_tt)
473 ttm_bo_tt_destroy(bo);
474 ttm_resource_free(bo, &bo->resource);
475 return 0;
476}
477
478static int ttm_bo_move_to_ghost(struct ttm_buffer_object *bo,
479 struct dma_fence *fence,
480 bool dst_use_tt)
481{
482 struct ttm_buffer_object *ghost_obj;
483 int ret;
484
485 /**
486 * This should help pipeline ordinary buffer moves.
487 *
488 * Hang old buffer memory on a new buffer object,
489 * and leave it to be released when the GPU
490 * operation has completed.
491 */
492
493 dma_fence_put(bo->moving);
494 bo->moving = dma_fence_get(fence);
495
496 ret = ttm_buffer_object_transfer(bo, &ghost_obj);
497 if (ret)
498 return ret;
499
500 dma_resv_add_excl_fence(&ghost_obj->base._resv, fence);
501
502 /**
503 * If we're not moving to fixed memory, the TTM object
504 * needs to stay alive. Otherwhise hang it on the ghost
505 * bo to be unbound and destroyed.
506 */
507
508 if (dst_use_tt)
509 ghost_obj->ttm = NULL;
510 else
511 bo->ttm = NULL;
512 bo->resource = NULL;
513
514 dma_resv_unlock(&ghost_obj->base._resv);
515 ttm_bo_put(ghost_obj);
516 return 0;
517}
518
519static void ttm_bo_move_pipeline_evict(struct ttm_buffer_object *bo,
520 struct dma_fence *fence)
521{
522 struct ttm_device *bdev = bo->bdev;
523 struct ttm_resource_manager *from;
524
525 from = ttm_manager_type(bdev, bo->resource->mem_type);
526
527 /**
528 * BO doesn't have a TTM we need to bind/unbind. Just remember
529 * this eviction and free up the allocation
530 */
531 spin_lock(&from->move_lock);
532 if (!from->move || dma_fence_is_later(fence, from->move)) {
533 dma_fence_put(from->move);
534 from->move = dma_fence_get(fence);
535 }
536 spin_unlock(&from->move_lock);
537
538 ttm_resource_free(bo, &bo->resource);
539
540 dma_fence_put(bo->moving);
541 bo->moving = dma_fence_get(fence);
542}
543
544int ttm_bo_move_accel_cleanup(struct ttm_buffer_object *bo,
545 struct dma_fence *fence,
546 bool evict,
547 bool pipeline,
548 struct ttm_resource *new_mem)
549{
550 struct ttm_device *bdev = bo->bdev;
551 struct ttm_resource_manager *from = ttm_manager_type(bdev, bo->resource->mem_type);
552 struct ttm_resource_manager *man = ttm_manager_type(bdev, new_mem->mem_type);
553 int ret = 0;
554
555 dma_resv_add_excl_fence(bo->base.resv, fence);
556 if (!evict)
557 ret = ttm_bo_move_to_ghost(bo, fence, man->use_tt);
558 else if (!from->use_tt && pipeline)
559 ttm_bo_move_pipeline_evict(bo, fence);
560 else
561 ret = ttm_bo_wait_free_node(bo, man->use_tt);
562
563 if (ret)
564 return ret;
565
566 ttm_bo_assign_mem(bo, new_mem);
567
568 return 0;
569}
570EXPORT_SYMBOL(ttm_bo_move_accel_cleanup);
571
572/**
573 * ttm_bo_pipeline_gutting - purge the contents of a bo
574 * @bo: The buffer object
575 *
576 * Purge the contents of a bo, async if the bo is not idle.
577 * After a successful call, the bo is left unpopulated in
578 * system placement. The function may wait uninterruptible
579 * for idle on OOM.
580 *
581 * Return: 0 if successful, negative error code on failure.
582 */
583int ttm_bo_pipeline_gutting(struct ttm_buffer_object *bo)
584{
585 static const struct ttm_place sys_mem = { .mem_type = TTM_PL_SYSTEM };
586 struct ttm_buffer_object *ghost;
587 struct ttm_resource *sys_res;
588 struct ttm_tt *ttm;
589 int ret;
590
591 ret = ttm_resource_alloc(bo, &sys_mem, &sys_res);
592 if (ret)
593 return ret;
594
595 /* If already idle, no need for ghost object dance. */
596 ret = ttm_bo_wait(bo, false, true);
597 if (ret != -EBUSY) {
598 if (!bo->ttm) {
599 /* See comment below about clearing. */
600 ret = ttm_tt_create(bo, true);
601 if (ret)
602 goto error_free_sys_mem;
603 } else {
604 ttm_tt_unpopulate(bo->bdev, bo->ttm);
605 if (bo->type == ttm_bo_type_device)
606 ttm_tt_mark_for_clear(bo->ttm);
607 }
608 ttm_resource_free(bo, &bo->resource);
609 ttm_bo_assign_mem(bo, sys_res);
610 return 0;
611 }
612
613 /*
614 * We need an unpopulated ttm_tt after giving our current one,
615 * if any, to the ghost object. And we can't afford to fail
616 * creating one *after* the operation. If the bo subsequently gets
617 * resurrected, make sure it's cleared (if ttm_bo_type_device)
618 * to avoid leaking sensitive information to user-space.
619 */
620
621 ttm = bo->ttm;
622 bo->ttm = NULL;
623 ret = ttm_tt_create(bo, true);
624 swap(bo->ttm, ttm);
625 if (ret)
626 goto error_free_sys_mem;
627
628 ret = ttm_buffer_object_transfer(bo, &ghost);
629 if (ret)
630 goto error_destroy_tt;
631
632 ret = dma_resv_copy_fences(&ghost->base._resv, bo->base.resv);
633 /* Last resort, wait for the BO to be idle when we are OOM */
634 if (ret)
635 ttm_bo_wait(bo, false, false);
636
637 dma_resv_unlock(&ghost->base._resv);
638 ttm_bo_put(ghost);
639 bo->ttm = ttm;
640 bo->resource = NULL;
641 ttm_bo_assign_mem(bo, sys_res);
642 return 0;
643
644error_destroy_tt:
645 ttm_tt_destroy(bo->bdev, ttm);
646
647error_free_sys_mem:
648 ttm_resource_free(bo, &sys_res);
649 return ret;
650}