xref: /openbmc/linux/drivers/gpu/drm/ttm/ttm_bo_util.c (revision 7587eb18)
1 /**************************************************************************
2  *
3  * Copyright (c) 2007-2009 VMware, Inc., Palo Alto, CA., USA
4  * All Rights Reserved.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the
8  * "Software"), to deal in the Software without restriction, including
9  * without limitation the rights to use, copy, modify, merge, publish,
10  * distribute, sub license, and/or sell copies of the Software, and to
11  * permit persons to whom the Software is furnished to do so, subject to
12  * the following conditions:
13  *
14  * The above copyright notice and this permission notice (including the
15  * next paragraph) shall be included in all copies or substantial portions
16  * of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24  * USE OR OTHER DEALINGS IN THE SOFTWARE.
25  *
26  **************************************************************************/
27 /*
28  * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29  */
30 
31 #include <drm/ttm/ttm_bo_driver.h>
32 #include <drm/ttm/ttm_placement.h>
33 #include <drm/drm_vma_manager.h>
34 #include <linux/io.h>
35 #include <linux/highmem.h>
36 #include <linux/wait.h>
37 #include <linux/slab.h>
38 #include <linux/vmalloc.h>
39 #include <linux/module.h>
40 #include <linux/reservation.h>
41 
42 void ttm_bo_free_old_node(struct ttm_buffer_object *bo)
43 {
44 	ttm_bo_mem_put(bo, &bo->mem);
45 }
46 
47 int ttm_bo_move_ttm(struct ttm_buffer_object *bo,
48 		    bool evict,
49 		    bool no_wait_gpu, struct ttm_mem_reg *new_mem)
50 {
51 	struct ttm_tt *ttm = bo->ttm;
52 	struct ttm_mem_reg *old_mem = &bo->mem;
53 	int ret;
54 
55 	if (old_mem->mem_type != TTM_PL_SYSTEM) {
56 		ttm_tt_unbind(ttm);
57 		ttm_bo_free_old_node(bo);
58 		ttm_flag_masked(&old_mem->placement, TTM_PL_FLAG_SYSTEM,
59 				TTM_PL_MASK_MEM);
60 		old_mem->mem_type = TTM_PL_SYSTEM;
61 	}
62 
63 	ret = ttm_tt_set_placement_caching(ttm, new_mem->placement);
64 	if (unlikely(ret != 0))
65 		return ret;
66 
67 	if (new_mem->mem_type != TTM_PL_SYSTEM) {
68 		ret = ttm_tt_bind(ttm, new_mem);
69 		if (unlikely(ret != 0))
70 			return ret;
71 	}
72 
73 	*old_mem = *new_mem;
74 	new_mem->mm_node = NULL;
75 
76 	return 0;
77 }
78 EXPORT_SYMBOL(ttm_bo_move_ttm);
79 
80 int ttm_mem_io_lock(struct ttm_mem_type_manager *man, bool interruptible)
81 {
82 	if (likely(man->io_reserve_fastpath))
83 		return 0;
84 
85 	if (interruptible)
86 		return mutex_lock_interruptible(&man->io_reserve_mutex);
87 
88 	mutex_lock(&man->io_reserve_mutex);
89 	return 0;
90 }
91 EXPORT_SYMBOL(ttm_mem_io_lock);
92 
93 void ttm_mem_io_unlock(struct ttm_mem_type_manager *man)
94 {
95 	if (likely(man->io_reserve_fastpath))
96 		return;
97 
98 	mutex_unlock(&man->io_reserve_mutex);
99 }
100 EXPORT_SYMBOL(ttm_mem_io_unlock);
101 
102 static int ttm_mem_io_evict(struct ttm_mem_type_manager *man)
103 {
104 	struct ttm_buffer_object *bo;
105 
106 	if (!man->use_io_reserve_lru || list_empty(&man->io_reserve_lru))
107 		return -EAGAIN;
108 
109 	bo = list_first_entry(&man->io_reserve_lru,
110 			      struct ttm_buffer_object,
111 			      io_reserve_lru);
112 	list_del_init(&bo->io_reserve_lru);
113 	ttm_bo_unmap_virtual_locked(bo);
114 
115 	return 0;
116 }
117 
118 
119 int ttm_mem_io_reserve(struct ttm_bo_device *bdev,
120 		       struct ttm_mem_reg *mem)
121 {
122 	struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
123 	int ret = 0;
124 
125 	if (!bdev->driver->io_mem_reserve)
126 		return 0;
127 	if (likely(man->io_reserve_fastpath))
128 		return bdev->driver->io_mem_reserve(bdev, mem);
129 
130 	if (bdev->driver->io_mem_reserve &&
131 	    mem->bus.io_reserved_count++ == 0) {
132 retry:
133 		ret = bdev->driver->io_mem_reserve(bdev, mem);
134 		if (ret == -EAGAIN) {
135 			ret = ttm_mem_io_evict(man);
136 			if (ret == 0)
137 				goto retry;
138 		}
139 	}
140 	return ret;
141 }
142 EXPORT_SYMBOL(ttm_mem_io_reserve);
143 
144 void ttm_mem_io_free(struct ttm_bo_device *bdev,
145 		     struct ttm_mem_reg *mem)
146 {
147 	struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
148 
149 	if (likely(man->io_reserve_fastpath))
150 		return;
151 
152 	if (bdev->driver->io_mem_reserve &&
153 	    --mem->bus.io_reserved_count == 0 &&
154 	    bdev->driver->io_mem_free)
155 		bdev->driver->io_mem_free(bdev, mem);
156 
157 }
158 EXPORT_SYMBOL(ttm_mem_io_free);
159 
160 int ttm_mem_io_reserve_vm(struct ttm_buffer_object *bo)
161 {
162 	struct ttm_mem_reg *mem = &bo->mem;
163 	int ret;
164 
165 	if (!mem->bus.io_reserved_vm) {
166 		struct ttm_mem_type_manager *man =
167 			&bo->bdev->man[mem->mem_type];
168 
169 		ret = ttm_mem_io_reserve(bo->bdev, mem);
170 		if (unlikely(ret != 0))
171 			return ret;
172 		mem->bus.io_reserved_vm = true;
173 		if (man->use_io_reserve_lru)
174 			list_add_tail(&bo->io_reserve_lru,
175 				      &man->io_reserve_lru);
176 	}
177 	return 0;
178 }
179 
180 void ttm_mem_io_free_vm(struct ttm_buffer_object *bo)
181 {
182 	struct ttm_mem_reg *mem = &bo->mem;
183 
184 	if (mem->bus.io_reserved_vm) {
185 		mem->bus.io_reserved_vm = false;
186 		list_del_init(&bo->io_reserve_lru);
187 		ttm_mem_io_free(bo->bdev, mem);
188 	}
189 }
190 
191 static int ttm_mem_reg_ioremap(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem,
192 			void **virtual)
193 {
194 	struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
195 	int ret;
196 	void *addr;
197 
198 	*virtual = NULL;
199 	(void) ttm_mem_io_lock(man, false);
200 	ret = ttm_mem_io_reserve(bdev, mem);
201 	ttm_mem_io_unlock(man);
202 	if (ret || !mem->bus.is_iomem)
203 		return ret;
204 
205 	if (mem->bus.addr) {
206 		addr = mem->bus.addr;
207 	} else {
208 		if (mem->placement & TTM_PL_FLAG_WC)
209 			addr = ioremap_wc(mem->bus.base + mem->bus.offset, mem->bus.size);
210 		else
211 			addr = ioremap_nocache(mem->bus.base + mem->bus.offset, mem->bus.size);
212 		if (!addr) {
213 			(void) ttm_mem_io_lock(man, false);
214 			ttm_mem_io_free(bdev, mem);
215 			ttm_mem_io_unlock(man);
216 			return -ENOMEM;
217 		}
218 	}
219 	*virtual = addr;
220 	return 0;
221 }
222 
223 static void ttm_mem_reg_iounmap(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem,
224 			 void *virtual)
225 {
226 	struct ttm_mem_type_manager *man;
227 
228 	man = &bdev->man[mem->mem_type];
229 
230 	if (virtual && mem->bus.addr == NULL)
231 		iounmap(virtual);
232 	(void) ttm_mem_io_lock(man, false);
233 	ttm_mem_io_free(bdev, mem);
234 	ttm_mem_io_unlock(man);
235 }
236 
237 static int ttm_copy_io_page(void *dst, void *src, unsigned long page)
238 {
239 	uint32_t *dstP =
240 	    (uint32_t *) ((unsigned long)dst + (page << PAGE_SHIFT));
241 	uint32_t *srcP =
242 	    (uint32_t *) ((unsigned long)src + (page << PAGE_SHIFT));
243 
244 	int i;
245 	for (i = 0; i < PAGE_SIZE / sizeof(uint32_t); ++i)
246 		iowrite32(ioread32(srcP++), dstP++);
247 	return 0;
248 }
249 
250 static int ttm_copy_io_ttm_page(struct ttm_tt *ttm, void *src,
251 				unsigned long page,
252 				pgprot_t prot)
253 {
254 	struct page *d = ttm->pages[page];
255 	void *dst;
256 
257 	if (!d)
258 		return -ENOMEM;
259 
260 	src = (void *)((unsigned long)src + (page << PAGE_SHIFT));
261 
262 #ifdef CONFIG_X86
263 	dst = kmap_atomic_prot(d, prot);
264 #else
265 	if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL))
266 		dst = vmap(&d, 1, 0, prot);
267 	else
268 		dst = kmap(d);
269 #endif
270 	if (!dst)
271 		return -ENOMEM;
272 
273 	memcpy_fromio(dst, src, PAGE_SIZE);
274 
275 #ifdef CONFIG_X86
276 	kunmap_atomic(dst);
277 #else
278 	if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL))
279 		vunmap(dst);
280 	else
281 		kunmap(d);
282 #endif
283 
284 	return 0;
285 }
286 
287 static int ttm_copy_ttm_io_page(struct ttm_tt *ttm, void *dst,
288 				unsigned long page,
289 				pgprot_t prot)
290 {
291 	struct page *s = ttm->pages[page];
292 	void *src;
293 
294 	if (!s)
295 		return -ENOMEM;
296 
297 	dst = (void *)((unsigned long)dst + (page << PAGE_SHIFT));
298 #ifdef CONFIG_X86
299 	src = kmap_atomic_prot(s, prot);
300 #else
301 	if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL))
302 		src = vmap(&s, 1, 0, prot);
303 	else
304 		src = kmap(s);
305 #endif
306 	if (!src)
307 		return -ENOMEM;
308 
309 	memcpy_toio(dst, src, PAGE_SIZE);
310 
311 #ifdef CONFIG_X86
312 	kunmap_atomic(src);
313 #else
314 	if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL))
315 		vunmap(src);
316 	else
317 		kunmap(s);
318 #endif
319 
320 	return 0;
321 }
322 
323 int ttm_bo_move_memcpy(struct ttm_buffer_object *bo,
324 		       bool evict, bool no_wait_gpu,
325 		       struct ttm_mem_reg *new_mem)
326 {
327 	struct ttm_bo_device *bdev = bo->bdev;
328 	struct ttm_mem_type_manager *man = &bdev->man[new_mem->mem_type];
329 	struct ttm_tt *ttm = bo->ttm;
330 	struct ttm_mem_reg *old_mem = &bo->mem;
331 	struct ttm_mem_reg old_copy = *old_mem;
332 	void *old_iomap;
333 	void *new_iomap;
334 	int ret;
335 	unsigned long i;
336 	unsigned long page;
337 	unsigned long add = 0;
338 	int dir;
339 
340 	ret = ttm_mem_reg_ioremap(bdev, old_mem, &old_iomap);
341 	if (ret)
342 		return ret;
343 	ret = ttm_mem_reg_ioremap(bdev, new_mem, &new_iomap);
344 	if (ret)
345 		goto out;
346 
347 	/*
348 	 * Single TTM move. NOP.
349 	 */
350 	if (old_iomap == NULL && new_iomap == NULL)
351 		goto out2;
352 
353 	/*
354 	 * Don't move nonexistent data. Clear destination instead.
355 	 */
356 	if (old_iomap == NULL &&
357 	    (ttm == NULL || (ttm->state == tt_unpopulated &&
358 			     !(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)))) {
359 		memset_io(new_iomap, 0, new_mem->num_pages*PAGE_SIZE);
360 		goto out2;
361 	}
362 
363 	/*
364 	 * TTM might be null for moves within the same region.
365 	 */
366 	if (ttm && ttm->state == tt_unpopulated) {
367 		ret = ttm->bdev->driver->ttm_tt_populate(ttm);
368 		if (ret)
369 			goto out1;
370 	}
371 
372 	add = 0;
373 	dir = 1;
374 
375 	if ((old_mem->mem_type == new_mem->mem_type) &&
376 	    (new_mem->start < old_mem->start + old_mem->size)) {
377 		dir = -1;
378 		add = new_mem->num_pages - 1;
379 	}
380 
381 	for (i = 0; i < new_mem->num_pages; ++i) {
382 		page = i * dir + add;
383 		if (old_iomap == NULL) {
384 			pgprot_t prot = ttm_io_prot(old_mem->placement,
385 						    PAGE_KERNEL);
386 			ret = ttm_copy_ttm_io_page(ttm, new_iomap, page,
387 						   prot);
388 		} else if (new_iomap == NULL) {
389 			pgprot_t prot = ttm_io_prot(new_mem->placement,
390 						    PAGE_KERNEL);
391 			ret = ttm_copy_io_ttm_page(ttm, old_iomap, page,
392 						   prot);
393 		} else
394 			ret = ttm_copy_io_page(new_iomap, old_iomap, page);
395 		if (ret)
396 			goto out1;
397 	}
398 	mb();
399 out2:
400 	old_copy = *old_mem;
401 	*old_mem = *new_mem;
402 	new_mem->mm_node = NULL;
403 
404 	if ((man->flags & TTM_MEMTYPE_FLAG_FIXED) && (ttm != NULL)) {
405 		ttm_tt_unbind(ttm);
406 		ttm_tt_destroy(ttm);
407 		bo->ttm = NULL;
408 	}
409 
410 out1:
411 	ttm_mem_reg_iounmap(bdev, old_mem, new_iomap);
412 out:
413 	ttm_mem_reg_iounmap(bdev, &old_copy, old_iomap);
414 
415 	/*
416 	 * On error, keep the mm node!
417 	 */
418 	if (!ret)
419 		ttm_bo_mem_put(bo, &old_copy);
420 	return ret;
421 }
422 EXPORT_SYMBOL(ttm_bo_move_memcpy);
423 
424 static void ttm_transfered_destroy(struct ttm_buffer_object *bo)
425 {
426 	kfree(bo);
427 }
428 
429 /**
430  * ttm_buffer_object_transfer
431  *
432  * @bo: A pointer to a struct ttm_buffer_object.
433  * @new_obj: A pointer to a pointer to a newly created ttm_buffer_object,
434  * holding the data of @bo with the old placement.
435  *
436  * This is a utility function that may be called after an accelerated move
437  * has been scheduled. A new buffer object is created as a placeholder for
438  * the old data while it's being copied. When that buffer object is idle,
439  * it can be destroyed, releasing the space of the old placement.
440  * Returns:
441  * !0: Failure.
442  */
443 
444 static int ttm_buffer_object_transfer(struct ttm_buffer_object *bo,
445 				      struct ttm_buffer_object **new_obj)
446 {
447 	struct ttm_buffer_object *fbo;
448 	int ret;
449 
450 	fbo = kmalloc(sizeof(*fbo), GFP_KERNEL);
451 	if (!fbo)
452 		return -ENOMEM;
453 
454 	*fbo = *bo;
455 
456 	/**
457 	 * Fix up members that we shouldn't copy directly:
458 	 * TODO: Explicit member copy would probably be better here.
459 	 */
460 
461 	INIT_LIST_HEAD(&fbo->ddestroy);
462 	INIT_LIST_HEAD(&fbo->lru);
463 	INIT_LIST_HEAD(&fbo->swap);
464 	INIT_LIST_HEAD(&fbo->io_reserve_lru);
465 	drm_vma_node_reset(&fbo->vma_node);
466 	atomic_set(&fbo->cpu_writers, 0);
467 
468 	kref_init(&fbo->list_kref);
469 	kref_init(&fbo->kref);
470 	fbo->destroy = &ttm_transfered_destroy;
471 	fbo->acc_size = 0;
472 	fbo->resv = &fbo->ttm_resv;
473 	reservation_object_init(fbo->resv);
474 	ret = ww_mutex_trylock(&fbo->resv->lock);
475 	WARN_ON(!ret);
476 
477 	*new_obj = fbo;
478 	return 0;
479 }
480 
481 pgprot_t ttm_io_prot(uint32_t caching_flags, pgprot_t tmp)
482 {
483 	/* Cached mappings need no adjustment */
484 	if (caching_flags & TTM_PL_FLAG_CACHED)
485 		return tmp;
486 
487 #if defined(__i386__) || defined(__x86_64__)
488 	if (caching_flags & TTM_PL_FLAG_WC)
489 		tmp = pgprot_writecombine(tmp);
490 	else if (boot_cpu_data.x86 > 3)
491 		tmp = pgprot_noncached(tmp);
492 #endif
493 #if defined(__ia64__) || defined(__arm__) || defined(__aarch64__) || \
494     defined(__powerpc__)
495 	if (caching_flags & TTM_PL_FLAG_WC)
496 		tmp = pgprot_writecombine(tmp);
497 	else
498 		tmp = pgprot_noncached(tmp);
499 #endif
500 #if defined(__sparc__) || defined(__mips__)
501 	tmp = pgprot_noncached(tmp);
502 #endif
503 	return tmp;
504 }
505 EXPORT_SYMBOL(ttm_io_prot);
506 
507 static int ttm_bo_ioremap(struct ttm_buffer_object *bo,
508 			  unsigned long offset,
509 			  unsigned long size,
510 			  struct ttm_bo_kmap_obj *map)
511 {
512 	struct ttm_mem_reg *mem = &bo->mem;
513 
514 	if (bo->mem.bus.addr) {
515 		map->bo_kmap_type = ttm_bo_map_premapped;
516 		map->virtual = (void *)(((u8 *)bo->mem.bus.addr) + offset);
517 	} else {
518 		map->bo_kmap_type = ttm_bo_map_iomap;
519 		if (mem->placement & TTM_PL_FLAG_WC)
520 			map->virtual = ioremap_wc(bo->mem.bus.base + bo->mem.bus.offset + offset,
521 						  size);
522 		else
523 			map->virtual = ioremap_nocache(bo->mem.bus.base + bo->mem.bus.offset + offset,
524 						       size);
525 	}
526 	return (!map->virtual) ? -ENOMEM : 0;
527 }
528 
529 static int ttm_bo_kmap_ttm(struct ttm_buffer_object *bo,
530 			   unsigned long start_page,
531 			   unsigned long num_pages,
532 			   struct ttm_bo_kmap_obj *map)
533 {
534 	struct ttm_mem_reg *mem = &bo->mem; pgprot_t prot;
535 	struct ttm_tt *ttm = bo->ttm;
536 	int ret;
537 
538 	BUG_ON(!ttm);
539 
540 	if (ttm->state == tt_unpopulated) {
541 		ret = ttm->bdev->driver->ttm_tt_populate(ttm);
542 		if (ret)
543 			return ret;
544 	}
545 
546 	if (num_pages == 1 && (mem->placement & TTM_PL_FLAG_CACHED)) {
547 		/*
548 		 * We're mapping a single page, and the desired
549 		 * page protection is consistent with the bo.
550 		 */
551 
552 		map->bo_kmap_type = ttm_bo_map_kmap;
553 		map->page = ttm->pages[start_page];
554 		map->virtual = kmap(map->page);
555 	} else {
556 		/*
557 		 * We need to use vmap to get the desired page protection
558 		 * or to make the buffer object look contiguous.
559 		 */
560 		prot = ttm_io_prot(mem->placement, PAGE_KERNEL);
561 		map->bo_kmap_type = ttm_bo_map_vmap;
562 		map->virtual = vmap(ttm->pages + start_page, num_pages,
563 				    0, prot);
564 	}
565 	return (!map->virtual) ? -ENOMEM : 0;
566 }
567 
568 int ttm_bo_kmap(struct ttm_buffer_object *bo,
569 		unsigned long start_page, unsigned long num_pages,
570 		struct ttm_bo_kmap_obj *map)
571 {
572 	struct ttm_mem_type_manager *man =
573 		&bo->bdev->man[bo->mem.mem_type];
574 	unsigned long offset, size;
575 	int ret;
576 
577 	BUG_ON(!list_empty(&bo->swap));
578 	map->virtual = NULL;
579 	map->bo = bo;
580 	if (num_pages > bo->num_pages)
581 		return -EINVAL;
582 	if (start_page > bo->num_pages)
583 		return -EINVAL;
584 #if 0
585 	if (num_pages > 1 && !capable(CAP_SYS_ADMIN))
586 		return -EPERM;
587 #endif
588 	(void) ttm_mem_io_lock(man, false);
589 	ret = ttm_mem_io_reserve(bo->bdev, &bo->mem);
590 	ttm_mem_io_unlock(man);
591 	if (ret)
592 		return ret;
593 	if (!bo->mem.bus.is_iomem) {
594 		return ttm_bo_kmap_ttm(bo, start_page, num_pages, map);
595 	} else {
596 		offset = start_page << PAGE_SHIFT;
597 		size = num_pages << PAGE_SHIFT;
598 		return ttm_bo_ioremap(bo, offset, size, map);
599 	}
600 }
601 EXPORT_SYMBOL(ttm_bo_kmap);
602 
603 void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map)
604 {
605 	struct ttm_buffer_object *bo = map->bo;
606 	struct ttm_mem_type_manager *man =
607 		&bo->bdev->man[bo->mem.mem_type];
608 
609 	if (!map->virtual)
610 		return;
611 	switch (map->bo_kmap_type) {
612 	case ttm_bo_map_iomap:
613 		iounmap(map->virtual);
614 		break;
615 	case ttm_bo_map_vmap:
616 		vunmap(map->virtual);
617 		break;
618 	case ttm_bo_map_kmap:
619 		kunmap(map->page);
620 		break;
621 	case ttm_bo_map_premapped:
622 		break;
623 	default:
624 		BUG();
625 	}
626 	(void) ttm_mem_io_lock(man, false);
627 	ttm_mem_io_free(map->bo->bdev, &map->bo->mem);
628 	ttm_mem_io_unlock(man);
629 	map->virtual = NULL;
630 	map->page = NULL;
631 }
632 EXPORT_SYMBOL(ttm_bo_kunmap);
633 
634 int ttm_bo_move_accel_cleanup(struct ttm_buffer_object *bo,
635 			      struct fence *fence,
636 			      bool evict,
637 			      bool no_wait_gpu,
638 			      struct ttm_mem_reg *new_mem)
639 {
640 	struct ttm_bo_device *bdev = bo->bdev;
641 	struct ttm_mem_type_manager *man = &bdev->man[new_mem->mem_type];
642 	struct ttm_mem_reg *old_mem = &bo->mem;
643 	int ret;
644 	struct ttm_buffer_object *ghost_obj;
645 
646 	reservation_object_add_excl_fence(bo->resv, fence);
647 	if (evict) {
648 		ret = ttm_bo_wait(bo, false, false);
649 		if (ret)
650 			return ret;
651 
652 		if ((man->flags & TTM_MEMTYPE_FLAG_FIXED) &&
653 		    (bo->ttm != NULL)) {
654 			ttm_tt_unbind(bo->ttm);
655 			ttm_tt_destroy(bo->ttm);
656 			bo->ttm = NULL;
657 		}
658 		ttm_bo_free_old_node(bo);
659 	} else {
660 		/**
661 		 * This should help pipeline ordinary buffer moves.
662 		 *
663 		 * Hang old buffer memory on a new buffer object,
664 		 * and leave it to be released when the GPU
665 		 * operation has completed.
666 		 */
667 
668 		set_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags);
669 
670 		ret = ttm_buffer_object_transfer(bo, &ghost_obj);
671 		if (ret)
672 			return ret;
673 
674 		reservation_object_add_excl_fence(ghost_obj->resv, fence);
675 
676 		/**
677 		 * If we're not moving to fixed memory, the TTM object
678 		 * needs to stay alive. Otherwhise hang it on the ghost
679 		 * bo to be unbound and destroyed.
680 		 */
681 
682 		if (!(man->flags & TTM_MEMTYPE_FLAG_FIXED))
683 			ghost_obj->ttm = NULL;
684 		else
685 			bo->ttm = NULL;
686 
687 		ttm_bo_unreserve(ghost_obj);
688 		ttm_bo_unref(&ghost_obj);
689 	}
690 
691 	*old_mem = *new_mem;
692 	new_mem->mm_node = NULL;
693 
694 	return 0;
695 }
696 EXPORT_SYMBOL(ttm_bo_move_accel_cleanup);
697