xref: /linux/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c (revision 4eca0ef49af9b2b0c52ef2b58e045ab34629796b)
1 /*
2  * Copyright 2016 Advanced Micro Devices, Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors: Christian König
23  */
24 
25 #include <linux/dma-mapping.h>
26 #include <drm/ttm/ttm_range_manager.h>
27 
28 #include "amdgpu.h"
29 #include "amdgpu_vm.h"
30 #include "amdgpu_res_cursor.h"
31 #include "amdgpu_atomfirmware.h"
32 #include "atom.h"
33 
34 struct amdgpu_vram_reservation {
35 	u64 start;
36 	u64 size;
37 	struct list_head allocated;
38 	struct list_head blocks;
39 };
40 
41 static inline struct amdgpu_vram_mgr *
42 to_vram_mgr(struct ttm_resource_manager *man)
43 {
44 	return container_of(man, struct amdgpu_vram_mgr, manager);
45 }
46 
47 static inline struct amdgpu_device *
48 to_amdgpu_device(struct amdgpu_vram_mgr *mgr)
49 {
50 	return container_of(mgr, struct amdgpu_device, mman.vram_mgr);
51 }
52 
53 static inline struct drm_buddy_block *
54 amdgpu_vram_mgr_first_block(struct list_head *list)
55 {
56 	return list_first_entry_or_null(list, struct drm_buddy_block, link);
57 }
58 
59 static inline bool amdgpu_is_vram_mgr_blocks_contiguous(struct list_head *head)
60 {
61 	struct drm_buddy_block *block;
62 	u64 start, size;
63 
64 	block = amdgpu_vram_mgr_first_block(head);
65 	if (!block)
66 		return false;
67 
68 	while (head != block->link.next) {
69 		start = amdgpu_vram_mgr_block_start(block);
70 		size = amdgpu_vram_mgr_block_size(block);
71 
72 		block = list_entry(block->link.next, struct drm_buddy_block, link);
73 		if (start + size != amdgpu_vram_mgr_block_start(block))
74 			return false;
75 	}
76 
77 	return true;
78 }
79 
80 static inline u64 amdgpu_vram_mgr_blocks_size(struct list_head *head)
81 {
82 	struct drm_buddy_block *block;
83 	u64 size = 0;
84 
85 	list_for_each_entry(block, head, link)
86 		size += amdgpu_vram_mgr_block_size(block);
87 
88 	return size;
89 }
90 
91 /**
92  * DOC: mem_info_vram_total
93  *
94  * The amdgpu driver provides a sysfs API for reporting current total VRAM
95  * available on the device
96  * The file mem_info_vram_total is used for this and returns the total
97  * amount of VRAM in bytes
98  */
99 static ssize_t amdgpu_mem_info_vram_total_show(struct device *dev,
100 		struct device_attribute *attr, char *buf)
101 {
102 	struct drm_device *ddev = dev_get_drvdata(dev);
103 	struct amdgpu_device *adev = drm_to_adev(ddev);
104 
105 	return sysfs_emit(buf, "%llu\n", adev->gmc.real_vram_size);
106 }
107 
108 /**
109  * DOC: mem_info_vis_vram_total
110  *
111  * The amdgpu driver provides a sysfs API for reporting current total
112  * visible VRAM available on the device
113  * The file mem_info_vis_vram_total is used for this and returns the total
114  * amount of visible VRAM in bytes
115  */
116 static ssize_t amdgpu_mem_info_vis_vram_total_show(struct device *dev,
117 		struct device_attribute *attr, char *buf)
118 {
119 	struct drm_device *ddev = dev_get_drvdata(dev);
120 	struct amdgpu_device *adev = drm_to_adev(ddev);
121 
122 	return sysfs_emit(buf, "%llu\n", adev->gmc.visible_vram_size);
123 }
124 
125 /**
126  * DOC: mem_info_vram_used
127  *
128  * The amdgpu driver provides a sysfs API for reporting current total VRAM
129  * available on the device
130  * The file mem_info_vram_used is used for this and returns the total
131  * amount of currently used VRAM in bytes
132  */
133 static ssize_t amdgpu_mem_info_vram_used_show(struct device *dev,
134 					      struct device_attribute *attr,
135 					      char *buf)
136 {
137 	struct drm_device *ddev = dev_get_drvdata(dev);
138 	struct amdgpu_device *adev = drm_to_adev(ddev);
139 	struct ttm_resource_manager *man = &adev->mman.vram_mgr.manager;
140 
141 	return sysfs_emit(buf, "%llu\n", ttm_resource_manager_usage(man));
142 }
143 
144 /**
145  * DOC: mem_info_vis_vram_used
146  *
147  * The amdgpu driver provides a sysfs API for reporting current total of
148  * used visible VRAM
149  * The file mem_info_vis_vram_used is used for this and returns the total
150  * amount of currently used visible VRAM in bytes
151  */
152 static ssize_t amdgpu_mem_info_vis_vram_used_show(struct device *dev,
153 						  struct device_attribute *attr,
154 						  char *buf)
155 {
156 	struct drm_device *ddev = dev_get_drvdata(dev);
157 	struct amdgpu_device *adev = drm_to_adev(ddev);
158 
159 	return sysfs_emit(buf, "%llu\n",
160 			  amdgpu_vram_mgr_vis_usage(&adev->mman.vram_mgr));
161 }
162 
163 /**
164  * DOC: mem_info_vram_vendor
165  *
166  * The amdgpu driver provides a sysfs API for reporting the vendor of the
167  * installed VRAM
168  * The file mem_info_vram_vendor is used for this and returns the name of the
169  * vendor.
170  */
171 static ssize_t amdgpu_mem_info_vram_vendor(struct device *dev,
172 					   struct device_attribute *attr,
173 					   char *buf)
174 {
175 	struct drm_device *ddev = dev_get_drvdata(dev);
176 	struct amdgpu_device *adev = drm_to_adev(ddev);
177 
178 	switch (adev->gmc.vram_vendor) {
179 	case SAMSUNG:
180 		return sysfs_emit(buf, "samsung\n");
181 	case INFINEON:
182 		return sysfs_emit(buf, "infineon\n");
183 	case ELPIDA:
184 		return sysfs_emit(buf, "elpida\n");
185 	case ETRON:
186 		return sysfs_emit(buf, "etron\n");
187 	case NANYA:
188 		return sysfs_emit(buf, "nanya\n");
189 	case HYNIX:
190 		return sysfs_emit(buf, "hynix\n");
191 	case MOSEL:
192 		return sysfs_emit(buf, "mosel\n");
193 	case WINBOND:
194 		return sysfs_emit(buf, "winbond\n");
195 	case ESMT:
196 		return sysfs_emit(buf, "esmt\n");
197 	case MICRON:
198 		return sysfs_emit(buf, "micron\n");
199 	default:
200 		return sysfs_emit(buf, "unknown\n");
201 	}
202 }
203 
204 static DEVICE_ATTR(mem_info_vram_total, S_IRUGO,
205 		   amdgpu_mem_info_vram_total_show, NULL);
206 static DEVICE_ATTR(mem_info_vis_vram_total, S_IRUGO,
207 		   amdgpu_mem_info_vis_vram_total_show,NULL);
208 static DEVICE_ATTR(mem_info_vram_used, S_IRUGO,
209 		   amdgpu_mem_info_vram_used_show, NULL);
210 static DEVICE_ATTR(mem_info_vis_vram_used, S_IRUGO,
211 		   amdgpu_mem_info_vis_vram_used_show, NULL);
212 static DEVICE_ATTR(mem_info_vram_vendor, S_IRUGO,
213 		   amdgpu_mem_info_vram_vendor, NULL);
214 
215 static struct attribute *amdgpu_vram_mgr_attributes[] = {
216 	&dev_attr_mem_info_vram_total.attr,
217 	&dev_attr_mem_info_vis_vram_total.attr,
218 	&dev_attr_mem_info_vram_used.attr,
219 	&dev_attr_mem_info_vis_vram_used.attr,
220 	&dev_attr_mem_info_vram_vendor.attr,
221 	NULL
222 };
223 
224 const struct attribute_group amdgpu_vram_mgr_attr_group = {
225 	.attrs = amdgpu_vram_mgr_attributes
226 };
227 
228 /**
229  * amdgpu_vram_mgr_vis_size - Calculate visible block size
230  *
231  * @adev: amdgpu_device pointer
232  * @block: DRM BUDDY block structure
233  *
234  * Calculate how many bytes of the DRM BUDDY block are inside visible VRAM
235  */
236 static u64 amdgpu_vram_mgr_vis_size(struct amdgpu_device *adev,
237 				    struct drm_buddy_block *block)
238 {
239 	u64 start = amdgpu_vram_mgr_block_start(block);
240 	u64 end = start + amdgpu_vram_mgr_block_size(block);
241 
242 	if (start >= adev->gmc.visible_vram_size)
243 		return 0;
244 
245 	return (end > adev->gmc.visible_vram_size ?
246 		adev->gmc.visible_vram_size : end) - start;
247 }
248 
249 /**
250  * amdgpu_vram_mgr_bo_visible_size - CPU visible BO size
251  *
252  * @bo: &amdgpu_bo buffer object (must be in VRAM)
253  *
254  * Returns:
255  * How much of the given &amdgpu_bo buffer object lies in CPU visible VRAM.
256  */
257 u64 amdgpu_vram_mgr_bo_visible_size(struct amdgpu_bo *bo)
258 {
259 	struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev);
260 	struct ttm_resource *res = bo->tbo.resource;
261 	struct amdgpu_vram_mgr_resource *vres = to_amdgpu_vram_mgr_resource(res);
262 	struct drm_buddy_block *block;
263 	u64 usage = 0;
264 
265 	if (amdgpu_gmc_vram_full_visible(&adev->gmc))
266 		return amdgpu_bo_size(bo);
267 
268 	if (res->start >= adev->gmc.visible_vram_size >> PAGE_SHIFT)
269 		return 0;
270 
271 	list_for_each_entry(block, &vres->blocks, link)
272 		usage += amdgpu_vram_mgr_vis_size(adev, block);
273 
274 	return usage;
275 }
276 
277 /* Commit the reservation of VRAM pages */
278 static void amdgpu_vram_mgr_do_reserve(struct ttm_resource_manager *man)
279 {
280 	struct amdgpu_vram_mgr *mgr = to_vram_mgr(man);
281 	struct amdgpu_device *adev = to_amdgpu_device(mgr);
282 	struct drm_buddy *mm = &mgr->mm;
283 	struct amdgpu_vram_reservation *rsv, *temp;
284 	struct drm_buddy_block *block;
285 	uint64_t vis_usage;
286 
287 	list_for_each_entry_safe(rsv, temp, &mgr->reservations_pending, blocks) {
288 		if (drm_buddy_alloc_blocks(mm, rsv->start, rsv->start + rsv->size,
289 					   rsv->size, mm->chunk_size, &rsv->allocated,
290 					   DRM_BUDDY_RANGE_ALLOCATION))
291 			continue;
292 
293 		block = amdgpu_vram_mgr_first_block(&rsv->allocated);
294 		if (!block)
295 			continue;
296 
297 		dev_dbg(adev->dev, "Reservation 0x%llx - %lld, Succeeded\n",
298 			rsv->start, rsv->size);
299 
300 		vis_usage = amdgpu_vram_mgr_vis_size(adev, block);
301 		atomic64_add(vis_usage, &mgr->vis_usage);
302 		spin_lock(&man->bdev->lru_lock);
303 		man->usage += rsv->size;
304 		spin_unlock(&man->bdev->lru_lock);
305 		list_move(&rsv->blocks, &mgr->reserved_pages);
306 	}
307 }
308 
309 /**
310  * amdgpu_vram_mgr_reserve_range - Reserve a range from VRAM
311  *
312  * @mgr: amdgpu_vram_mgr pointer
313  * @start: start address of the range in VRAM
314  * @size: size of the range
315  *
316  * Reserve memory from start address with the specified size in VRAM
317  */
318 int amdgpu_vram_mgr_reserve_range(struct amdgpu_vram_mgr *mgr,
319 				  uint64_t start, uint64_t size)
320 {
321 	struct amdgpu_vram_reservation *rsv;
322 
323 	rsv = kzalloc(sizeof(*rsv), GFP_KERNEL);
324 	if (!rsv)
325 		return -ENOMEM;
326 
327 	INIT_LIST_HEAD(&rsv->allocated);
328 	INIT_LIST_HEAD(&rsv->blocks);
329 
330 	rsv->start = start;
331 	rsv->size = size;
332 
333 	mutex_lock(&mgr->lock);
334 	list_add_tail(&rsv->blocks, &mgr->reservations_pending);
335 	amdgpu_vram_mgr_do_reserve(&mgr->manager);
336 	mutex_unlock(&mgr->lock);
337 
338 	return 0;
339 }
340 
341 /**
342  * amdgpu_vram_mgr_query_page_status - query the reservation status
343  *
344  * @mgr: amdgpu_vram_mgr pointer
345  * @start: start address of a page in VRAM
346  *
347  * Returns:
348  *	-EBUSY: the page is still hold and in pending list
349  *	0: the page has been reserved
350  *	-ENOENT: the input page is not a reservation
351  */
352 int amdgpu_vram_mgr_query_page_status(struct amdgpu_vram_mgr *mgr,
353 				      uint64_t start)
354 {
355 	struct amdgpu_vram_reservation *rsv;
356 	int ret;
357 
358 	mutex_lock(&mgr->lock);
359 
360 	list_for_each_entry(rsv, &mgr->reservations_pending, blocks) {
361 		if (rsv->start <= start &&
362 		    (start < (rsv->start + rsv->size))) {
363 			ret = -EBUSY;
364 			goto out;
365 		}
366 	}
367 
368 	list_for_each_entry(rsv, &mgr->reserved_pages, blocks) {
369 		if (rsv->start <= start &&
370 		    (start < (rsv->start + rsv->size))) {
371 			ret = 0;
372 			goto out;
373 		}
374 	}
375 
376 	ret = -ENOENT;
377 out:
378 	mutex_unlock(&mgr->lock);
379 	return ret;
380 }
381 
382 static void amdgpu_dummy_vram_mgr_debug(struct ttm_resource_manager *man,
383 				  struct drm_printer *printer)
384 {
385 	DRM_DEBUG_DRIVER("Dummy vram mgr debug\n");
386 }
387 
388 static bool amdgpu_dummy_vram_mgr_compatible(struct ttm_resource_manager *man,
389 				       struct ttm_resource *res,
390 				       const struct ttm_place *place,
391 				       size_t size)
392 {
393 	DRM_DEBUG_DRIVER("Dummy vram mgr compatible\n");
394 	return false;
395 }
396 
397 static bool amdgpu_dummy_vram_mgr_intersects(struct ttm_resource_manager *man,
398 				       struct ttm_resource *res,
399 				       const struct ttm_place *place,
400 				       size_t size)
401 {
402 	DRM_DEBUG_DRIVER("Dummy vram mgr intersects\n");
403 	return true;
404 }
405 
406 static void amdgpu_dummy_vram_mgr_del(struct ttm_resource_manager *man,
407 				struct ttm_resource *res)
408 {
409 	DRM_DEBUG_DRIVER("Dummy vram mgr deleted\n");
410 }
411 
412 static int amdgpu_dummy_vram_mgr_new(struct ttm_resource_manager *man,
413 			       struct ttm_buffer_object *tbo,
414 			       const struct ttm_place *place,
415 			       struct ttm_resource **res)
416 {
417 	DRM_DEBUG_DRIVER("Dummy vram mgr new\n");
418 	return -ENOSPC;
419 }
420 
421 /**
422  * amdgpu_vram_mgr_new - allocate new ranges
423  *
424  * @man: TTM memory type manager
425  * @tbo: TTM BO we need this range for
426  * @place: placement flags and restrictions
427  * @res: the resulting mem object
428  *
429  * Allocate VRAM for the given BO.
430  */
431 static int amdgpu_vram_mgr_new(struct ttm_resource_manager *man,
432 			       struct ttm_buffer_object *tbo,
433 			       const struct ttm_place *place,
434 			       struct ttm_resource **res)
435 {
436 	struct amdgpu_vram_mgr *mgr = to_vram_mgr(man);
437 	struct amdgpu_device *adev = to_amdgpu_device(mgr);
438 	u64 vis_usage = 0, max_bytes, min_block_size;
439 	struct amdgpu_vram_mgr_resource *vres;
440 	u64 size, remaining_size, lpfn, fpfn;
441 	struct drm_buddy *mm = &mgr->mm;
442 	struct drm_buddy_block *block;
443 	unsigned long pages_per_block;
444 	int r;
445 
446 	lpfn = (u64)place->lpfn << PAGE_SHIFT;
447 	if (!lpfn)
448 		lpfn = man->size;
449 
450 	fpfn = (u64)place->fpfn << PAGE_SHIFT;
451 
452 	max_bytes = adev->gmc.mc_vram_size;
453 	if (tbo->type != ttm_bo_type_kernel)
454 		max_bytes -= AMDGPU_VM_RESERVED_VRAM;
455 
456 	if (place->flags & TTM_PL_FLAG_CONTIGUOUS) {
457 		pages_per_block = ~0ul;
458 	} else {
459 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
460 		pages_per_block = HPAGE_PMD_NR;
461 #else
462 		/* default to 2MB */
463 		pages_per_block = 2UL << (20UL - PAGE_SHIFT);
464 #endif
465 		pages_per_block = max_t(uint32_t, pages_per_block,
466 					tbo->page_alignment);
467 	}
468 
469 	vres = kzalloc(sizeof(*vres), GFP_KERNEL);
470 	if (!vres)
471 		return -ENOMEM;
472 
473 	ttm_resource_init(tbo, place, &vres->base);
474 
475 	/* bail out quickly if there's likely not enough VRAM for this BO */
476 	if (ttm_resource_manager_usage(man) > max_bytes) {
477 		r = -ENOSPC;
478 		goto error_fini;
479 	}
480 
481 	INIT_LIST_HEAD(&vres->blocks);
482 
483 	if (place->flags & TTM_PL_FLAG_TOPDOWN)
484 		vres->flags |= DRM_BUDDY_TOPDOWN_ALLOCATION;
485 
486 	if (place->flags & TTM_PL_FLAG_CONTIGUOUS)
487 		vres->flags |= DRM_BUDDY_CONTIGUOUS_ALLOCATION;
488 
489 	if (fpfn || lpfn != mgr->mm.size)
490 		/* Allocate blocks in desired range */
491 		vres->flags |= DRM_BUDDY_RANGE_ALLOCATION;
492 
493 	remaining_size = (u64)vres->base.size;
494 
495 	mutex_lock(&mgr->lock);
496 	while (remaining_size) {
497 		if (tbo->page_alignment)
498 			min_block_size = (u64)tbo->page_alignment << PAGE_SHIFT;
499 		else
500 			min_block_size = mgr->default_page_size;
501 
502 		BUG_ON(min_block_size < mm->chunk_size);
503 
504 		/* Limit maximum size to 2GiB due to SG table limitations */
505 		size = min(remaining_size, 2ULL << 30);
506 
507 		if ((size >= (u64)pages_per_block << PAGE_SHIFT) &&
508 				!(size & (((u64)pages_per_block << PAGE_SHIFT) - 1)))
509 			min_block_size = (u64)pages_per_block << PAGE_SHIFT;
510 
511 		r = drm_buddy_alloc_blocks(mm, fpfn,
512 					   lpfn,
513 					   size,
514 					   min_block_size,
515 					   &vres->blocks,
516 					   vres->flags);
517 		if (unlikely(r))
518 			goto error_free_blocks;
519 
520 		if (size > remaining_size)
521 			remaining_size = 0;
522 		else
523 			remaining_size -= size;
524 	}
525 	mutex_unlock(&mgr->lock);
526 
527 	vres->base.start = 0;
528 	size = max_t(u64, amdgpu_vram_mgr_blocks_size(&vres->blocks),
529 		     vres->base.size);
530 	list_for_each_entry(block, &vres->blocks, link) {
531 		unsigned long start;
532 
533 		start = amdgpu_vram_mgr_block_start(block) +
534 			amdgpu_vram_mgr_block_size(block);
535 		start >>= PAGE_SHIFT;
536 
537 		if (start > PFN_UP(size))
538 			start -= PFN_UP(size);
539 		else
540 			start = 0;
541 		vres->base.start = max(vres->base.start, start);
542 
543 		vis_usage += amdgpu_vram_mgr_vis_size(adev, block);
544 	}
545 
546 	if (amdgpu_is_vram_mgr_blocks_contiguous(&vres->blocks))
547 		vres->base.placement |= TTM_PL_FLAG_CONTIGUOUS;
548 
549 	if (adev->gmc.xgmi.connected_to_cpu)
550 		vres->base.bus.caching = ttm_cached;
551 	else
552 		vres->base.bus.caching = ttm_write_combined;
553 
554 	atomic64_add(vis_usage, &mgr->vis_usage);
555 	*res = &vres->base;
556 	return 0;
557 
558 error_free_blocks:
559 	drm_buddy_free_list(mm, &vres->blocks);
560 	mutex_unlock(&mgr->lock);
561 error_fini:
562 	ttm_resource_fini(man, &vres->base);
563 	kfree(vres);
564 
565 	return r;
566 }
567 
568 /**
569  * amdgpu_vram_mgr_del - free ranges
570  *
571  * @man: TTM memory type manager
572  * @res: TTM memory object
573  *
574  * Free the allocated VRAM again.
575  */
576 static void amdgpu_vram_mgr_del(struct ttm_resource_manager *man,
577 				struct ttm_resource *res)
578 {
579 	struct amdgpu_vram_mgr_resource *vres = to_amdgpu_vram_mgr_resource(res);
580 	struct amdgpu_vram_mgr *mgr = to_vram_mgr(man);
581 	struct amdgpu_device *adev = to_amdgpu_device(mgr);
582 	struct drm_buddy *mm = &mgr->mm;
583 	struct drm_buddy_block *block;
584 	uint64_t vis_usage = 0;
585 
586 	mutex_lock(&mgr->lock);
587 	list_for_each_entry(block, &vres->blocks, link)
588 		vis_usage += amdgpu_vram_mgr_vis_size(adev, block);
589 
590 	amdgpu_vram_mgr_do_reserve(man);
591 
592 	drm_buddy_free_list(mm, &vres->blocks);
593 	mutex_unlock(&mgr->lock);
594 
595 	atomic64_sub(vis_usage, &mgr->vis_usage);
596 
597 	ttm_resource_fini(man, res);
598 	kfree(vres);
599 }
600 
601 /**
602  * amdgpu_vram_mgr_alloc_sgt - allocate and fill a sg table
603  *
604  * @adev: amdgpu device pointer
605  * @res: TTM memory object
606  * @offset: byte offset from the base of VRAM BO
607  * @length: number of bytes to export in sg_table
608  * @dev: the other device
609  * @dir: dma direction
610  * @sgt: resulting sg table
611  *
612  * Allocate and fill a sg table from a VRAM allocation.
613  */
614 int amdgpu_vram_mgr_alloc_sgt(struct amdgpu_device *adev,
615 			      struct ttm_resource *res,
616 			      u64 offset, u64 length,
617 			      struct device *dev,
618 			      enum dma_data_direction dir,
619 			      struct sg_table **sgt)
620 {
621 	struct amdgpu_res_cursor cursor;
622 	struct scatterlist *sg;
623 	int num_entries = 0;
624 	int i, r;
625 
626 	*sgt = kmalloc(sizeof(**sgt), GFP_KERNEL);
627 	if (!*sgt)
628 		return -ENOMEM;
629 
630 	/* Determine the number of DRM_BUDDY blocks to export */
631 	amdgpu_res_first(res, offset, length, &cursor);
632 	while (cursor.remaining) {
633 		num_entries++;
634 		amdgpu_res_next(&cursor, cursor.size);
635 	}
636 
637 	r = sg_alloc_table(*sgt, num_entries, GFP_KERNEL);
638 	if (r)
639 		goto error_free;
640 
641 	/* Initialize scatterlist nodes of sg_table */
642 	for_each_sgtable_sg((*sgt), sg, i)
643 		sg->length = 0;
644 
645 	/*
646 	 * Walk down DRM_BUDDY blocks to populate scatterlist nodes
647 	 * @note: Use iterator api to get first the DRM_BUDDY block
648 	 * and the number of bytes from it. Access the following
649 	 * DRM_BUDDY block(s) if more buffer needs to exported
650 	 */
651 	amdgpu_res_first(res, offset, length, &cursor);
652 	for_each_sgtable_sg((*sgt), sg, i) {
653 		phys_addr_t phys = cursor.start + adev->gmc.aper_base;
654 		size_t size = cursor.size;
655 		dma_addr_t addr;
656 
657 		addr = dma_map_resource(dev, phys, size, dir,
658 					DMA_ATTR_SKIP_CPU_SYNC);
659 		r = dma_mapping_error(dev, addr);
660 		if (r)
661 			goto error_unmap;
662 
663 		sg_set_page(sg, NULL, size, 0);
664 		sg_dma_address(sg) = addr;
665 		sg_dma_len(sg) = size;
666 
667 		amdgpu_res_next(&cursor, cursor.size);
668 	}
669 
670 	return 0;
671 
672 error_unmap:
673 	for_each_sgtable_sg((*sgt), sg, i) {
674 		if (!sg->length)
675 			continue;
676 
677 		dma_unmap_resource(dev, sg->dma_address,
678 				   sg->length, dir,
679 				   DMA_ATTR_SKIP_CPU_SYNC);
680 	}
681 	sg_free_table(*sgt);
682 
683 error_free:
684 	kfree(*sgt);
685 	return r;
686 }
687 
688 /**
689  * amdgpu_vram_mgr_free_sgt - allocate and fill a sg table
690  *
691  * @dev: device pointer
692  * @dir: data direction of resource to unmap
693  * @sgt: sg table to free
694  *
695  * Free a previously allocate sg table.
696  */
697 void amdgpu_vram_mgr_free_sgt(struct device *dev,
698 			      enum dma_data_direction dir,
699 			      struct sg_table *sgt)
700 {
701 	struct scatterlist *sg;
702 	int i;
703 
704 	for_each_sgtable_sg(sgt, sg, i)
705 		dma_unmap_resource(dev, sg->dma_address,
706 				   sg->length, dir,
707 				   DMA_ATTR_SKIP_CPU_SYNC);
708 	sg_free_table(sgt);
709 	kfree(sgt);
710 }
711 
712 /**
713  * amdgpu_vram_mgr_vis_usage - how many bytes are used in the visible part
714  *
715  * @mgr: amdgpu_vram_mgr pointer
716  *
717  * Returns how many bytes are used in the visible part of VRAM
718  */
719 uint64_t amdgpu_vram_mgr_vis_usage(struct amdgpu_vram_mgr *mgr)
720 {
721 	return atomic64_read(&mgr->vis_usage);
722 }
723 
724 /**
725  * amdgpu_vram_mgr_intersects - test each drm buddy block for intersection
726  *
727  * @man: TTM memory type manager
728  * @res: The resource to test
729  * @place: The place to test against
730  * @size: Size of the new allocation
731  *
732  * Test each drm buddy block for intersection for eviction decision.
733  */
734 static bool amdgpu_vram_mgr_intersects(struct ttm_resource_manager *man,
735 				       struct ttm_resource *res,
736 				       const struct ttm_place *place,
737 				       size_t size)
738 {
739 	struct amdgpu_vram_mgr_resource *mgr = to_amdgpu_vram_mgr_resource(res);
740 	struct drm_buddy_block *block;
741 
742 	/* Check each drm buddy block individually */
743 	list_for_each_entry(block, &mgr->blocks, link) {
744 		unsigned long fpfn =
745 			amdgpu_vram_mgr_block_start(block) >> PAGE_SHIFT;
746 		unsigned long lpfn = fpfn +
747 			(amdgpu_vram_mgr_block_size(block) >> PAGE_SHIFT);
748 
749 		if (place->fpfn < lpfn &&
750 		    (!place->lpfn || place->lpfn > fpfn))
751 			return true;
752 	}
753 
754 	return false;
755 }
756 
757 /**
758  * amdgpu_vram_mgr_compatible - test each drm buddy block for compatibility
759  *
760  * @man: TTM memory type manager
761  * @res: The resource to test
762  * @place: The place to test against
763  * @size: Size of the new allocation
764  *
765  * Test each drm buddy block for placement compatibility.
766  */
767 static bool amdgpu_vram_mgr_compatible(struct ttm_resource_manager *man,
768 				       struct ttm_resource *res,
769 				       const struct ttm_place *place,
770 				       size_t size)
771 {
772 	struct amdgpu_vram_mgr_resource *mgr = to_amdgpu_vram_mgr_resource(res);
773 	struct drm_buddy_block *block;
774 
775 	/* Check each drm buddy block individually */
776 	list_for_each_entry(block, &mgr->blocks, link) {
777 		unsigned long fpfn =
778 			amdgpu_vram_mgr_block_start(block) >> PAGE_SHIFT;
779 		unsigned long lpfn = fpfn +
780 			(amdgpu_vram_mgr_block_size(block) >> PAGE_SHIFT);
781 
782 		if (fpfn < place->fpfn ||
783 		    (place->lpfn && lpfn > place->lpfn))
784 			return false;
785 	}
786 
787 	return true;
788 }
789 
790 /**
791  * amdgpu_vram_mgr_debug - dump VRAM table
792  *
793  * @man: TTM memory type manager
794  * @printer: DRM printer to use
795  *
796  * Dump the table content using printk.
797  */
798 static void amdgpu_vram_mgr_debug(struct ttm_resource_manager *man,
799 				  struct drm_printer *printer)
800 {
801 	struct amdgpu_vram_mgr *mgr = to_vram_mgr(man);
802 	struct drm_buddy *mm = &mgr->mm;
803 	struct amdgpu_vram_reservation *rsv;
804 
805 	drm_printf(printer, "  vis usage:%llu\n",
806 		   amdgpu_vram_mgr_vis_usage(mgr));
807 
808 	mutex_lock(&mgr->lock);
809 	drm_printf(printer, "default_page_size: %lluKiB\n",
810 		   mgr->default_page_size >> 10);
811 
812 	drm_buddy_print(mm, printer);
813 
814 	drm_printf(printer, "reserved:\n");
815 	list_for_each_entry(rsv, &mgr->reserved_pages, blocks)
816 		drm_printf(printer, "%#018llx-%#018llx: %llu\n",
817 			rsv->start, rsv->start + rsv->size, rsv->size);
818 	mutex_unlock(&mgr->lock);
819 }
820 
821 static const struct ttm_resource_manager_func amdgpu_dummy_vram_mgr_func = {
822 	.alloc	= amdgpu_dummy_vram_mgr_new,
823 	.free	= amdgpu_dummy_vram_mgr_del,
824 	.intersects = amdgpu_dummy_vram_mgr_intersects,
825 	.compatible = amdgpu_dummy_vram_mgr_compatible,
826 	.debug	= amdgpu_dummy_vram_mgr_debug
827 };
828 
829 static const struct ttm_resource_manager_func amdgpu_vram_mgr_func = {
830 	.alloc	= amdgpu_vram_mgr_new,
831 	.free	= amdgpu_vram_mgr_del,
832 	.intersects = amdgpu_vram_mgr_intersects,
833 	.compatible = amdgpu_vram_mgr_compatible,
834 	.debug	= amdgpu_vram_mgr_debug
835 };
836 
837 /**
838  * amdgpu_vram_mgr_init - init VRAM manager and DRM MM
839  *
840  * @adev: amdgpu_device pointer
841  *
842  * Allocate and initialize the VRAM manager.
843  */
844 int amdgpu_vram_mgr_init(struct amdgpu_device *adev)
845 {
846 	struct amdgpu_vram_mgr *mgr = &adev->mman.vram_mgr;
847 	struct ttm_resource_manager *man = &mgr->manager;
848 	int err;
849 
850 	ttm_resource_manager_init(man, &adev->mman.bdev,
851 				  adev->gmc.real_vram_size);
852 
853 	mutex_init(&mgr->lock);
854 	INIT_LIST_HEAD(&mgr->reservations_pending);
855 	INIT_LIST_HEAD(&mgr->reserved_pages);
856 	mgr->default_page_size = PAGE_SIZE;
857 
858 	if (!adev->gmc.is_app_apu) {
859 		man->func = &amdgpu_vram_mgr_func;
860 
861 		err = drm_buddy_init(&mgr->mm, man->size, PAGE_SIZE);
862 		if (err)
863 			return err;
864 	} else {
865 		man->func = &amdgpu_dummy_vram_mgr_func;
866 		DRM_INFO("Setup dummy vram mgr\n");
867 	}
868 
869 	ttm_set_driver_manager(&adev->mman.bdev, TTM_PL_VRAM, &mgr->manager);
870 	ttm_resource_manager_set_used(man, true);
871 	return 0;
872 }
873 
874 /**
875  * amdgpu_vram_mgr_fini - free and destroy VRAM manager
876  *
877  * @adev: amdgpu_device pointer
878  *
879  * Destroy and free the VRAM manager, returns -EBUSY if ranges are still
880  * allocated inside it.
881  */
882 void amdgpu_vram_mgr_fini(struct amdgpu_device *adev)
883 {
884 	struct amdgpu_vram_mgr *mgr = &adev->mman.vram_mgr;
885 	struct ttm_resource_manager *man = &mgr->manager;
886 	int ret;
887 	struct amdgpu_vram_reservation *rsv, *temp;
888 
889 	ttm_resource_manager_set_used(man, false);
890 
891 	ret = ttm_resource_manager_evict_all(&adev->mman.bdev, man);
892 	if (ret)
893 		return;
894 
895 	mutex_lock(&mgr->lock);
896 	list_for_each_entry_safe(rsv, temp, &mgr->reservations_pending, blocks)
897 		kfree(rsv);
898 
899 	list_for_each_entry_safe(rsv, temp, &mgr->reserved_pages, blocks) {
900 		drm_buddy_free_list(&mgr->mm, &rsv->allocated);
901 		kfree(rsv);
902 	}
903 	if (!adev->gmc.is_app_apu)
904 		drm_buddy_fini(&mgr->mm);
905 	mutex_unlock(&mgr->lock);
906 
907 	ttm_resource_manager_cleanup(man);
908 	ttm_set_driver_manager(&adev->mman.bdev, TTM_PL_VRAM, NULL);
909 }
910