xref: /linux/drivers/gpu/drm/amd/amdkfd/kfd_svm.c (revision db5b5c679e6cad2bb147337af6c378d278231b45)
1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /*
3  * Copyright 2020-2021 Advanced Micro Devices, Inc.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be included in
13  * all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
19  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
20  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
21  * OTHER DEALINGS IN THE SOFTWARE.
22  */
23 
24 #include <linux/types.h>
25 #include <linux/sched/task.h>
26 #include "amdgpu_sync.h"
27 #include "amdgpu_object.h"
28 #include "amdgpu_vm.h"
29 #include "amdgpu_mn.h"
30 #include "amdgpu.h"
31 #include "amdgpu_xgmi.h"
32 #include "kfd_priv.h"
33 #include "kfd_svm.h"
34 #include "kfd_migrate.h"
35 
36 #ifdef dev_fmt
37 #undef dev_fmt
38 #endif
39 #define dev_fmt(fmt) "kfd_svm: %s: " fmt, __func__
40 
41 #define AMDGPU_SVM_RANGE_RESTORE_DELAY_MS 1
42 
43 /* Long enough to ensure no retry fault comes after svm range is restored and
44  * page table is updated.
45  */
46 #define AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING	2000
47 
48 static void svm_range_evict_svm_bo_worker(struct work_struct *work);
49 static bool
50 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
51 				    const struct mmu_notifier_range *range,
52 				    unsigned long cur_seq);
53 static int
54 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
55 		   uint64_t *bo_s, uint64_t *bo_l);
56 static const struct mmu_interval_notifier_ops svm_range_mn_ops = {
57 	.invalidate = svm_range_cpu_invalidate_pagetables,
58 };
59 
60 /**
61  * svm_range_unlink - unlink svm_range from lists and interval tree
62  * @prange: svm range structure to be removed
63  *
64  * Remove the svm_range from the svms and svm_bo lists and the svms
65  * interval tree.
66  *
67  * Context: The caller must hold svms->lock
68  */
69 static void svm_range_unlink(struct svm_range *prange)
70 {
71 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
72 		 prange, prange->start, prange->last);
73 
74 	if (prange->svm_bo) {
75 		spin_lock(&prange->svm_bo->list_lock);
76 		list_del(&prange->svm_bo_list);
77 		spin_unlock(&prange->svm_bo->list_lock);
78 	}
79 
80 	list_del(&prange->list);
81 	if (prange->it_node.start != 0 && prange->it_node.last != 0)
82 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
83 }
84 
85 static void
86 svm_range_add_notifier_locked(struct mm_struct *mm, struct svm_range *prange)
87 {
88 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
89 		 prange, prange->start, prange->last);
90 
91 	mmu_interval_notifier_insert_locked(&prange->notifier, mm,
92 				     prange->start << PAGE_SHIFT,
93 				     prange->npages << PAGE_SHIFT,
94 				     &svm_range_mn_ops);
95 }
96 
97 /**
98  * svm_range_add_to_svms - add svm range to svms
99  * @prange: svm range structure to be added
100  *
101  * Add the svm range to svms interval tree and link list
102  *
103  * Context: The caller must hold svms->lock
104  */
105 static void svm_range_add_to_svms(struct svm_range *prange)
106 {
107 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
108 		 prange, prange->start, prange->last);
109 
110 	list_add_tail(&prange->list, &prange->svms->list);
111 	prange->it_node.start = prange->start;
112 	prange->it_node.last = prange->last;
113 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
114 }
115 
116 static void svm_range_remove_notifier(struct svm_range *prange)
117 {
118 	pr_debug("remove notifier svms 0x%p prange 0x%p [0x%lx 0x%lx]\n",
119 		 prange->svms, prange,
120 		 prange->notifier.interval_tree.start >> PAGE_SHIFT,
121 		 prange->notifier.interval_tree.last >> PAGE_SHIFT);
122 
123 	if (prange->notifier.interval_tree.start != 0 &&
124 	    prange->notifier.interval_tree.last != 0)
125 		mmu_interval_notifier_remove(&prange->notifier);
126 }
127 
128 static bool
129 svm_is_valid_dma_mapping_addr(struct device *dev, dma_addr_t dma_addr)
130 {
131 	return dma_addr && !dma_mapping_error(dev, dma_addr) &&
132 	       !(dma_addr & SVM_RANGE_VRAM_DOMAIN);
133 }
134 
135 static int
136 svm_range_dma_map_dev(struct amdgpu_device *adev, struct svm_range *prange,
137 		      unsigned long offset, unsigned long npages,
138 		      unsigned long *hmm_pfns, uint32_t gpuidx)
139 {
140 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
141 	dma_addr_t *addr = prange->dma_addr[gpuidx];
142 	struct device *dev = adev->dev;
143 	struct page *page;
144 	int i, r;
145 
146 	if (!addr) {
147 		addr = kvmalloc_array(prange->npages, sizeof(*addr),
148 				      GFP_KERNEL | __GFP_ZERO);
149 		if (!addr)
150 			return -ENOMEM;
151 		prange->dma_addr[gpuidx] = addr;
152 	}
153 
154 	addr += offset;
155 	for (i = 0; i < npages; i++) {
156 		if (svm_is_valid_dma_mapping_addr(dev, addr[i]))
157 			dma_unmap_page(dev, addr[i], PAGE_SIZE, dir);
158 
159 		page = hmm_pfn_to_page(hmm_pfns[i]);
160 		if (is_zone_device_page(page)) {
161 			struct amdgpu_device *bo_adev =
162 					amdgpu_ttm_adev(prange->svm_bo->bo->tbo.bdev);
163 
164 			addr[i] = (hmm_pfns[i] << PAGE_SHIFT) +
165 				   bo_adev->vm_manager.vram_base_offset -
166 				   bo_adev->kfd.dev->pgmap.range.start;
167 			addr[i] |= SVM_RANGE_VRAM_DOMAIN;
168 			pr_debug_ratelimited("vram address: 0x%llx\n", addr[i]);
169 			continue;
170 		}
171 		addr[i] = dma_map_page(dev, page, 0, PAGE_SIZE, dir);
172 		r = dma_mapping_error(dev, addr[i]);
173 		if (r) {
174 			dev_err(dev, "failed %d dma_map_page\n", r);
175 			return r;
176 		}
177 		pr_debug_ratelimited("dma mapping 0x%llx for page addr 0x%lx\n",
178 				     addr[i] >> PAGE_SHIFT, page_to_pfn(page));
179 	}
180 	return 0;
181 }
182 
183 static int
184 svm_range_dma_map(struct svm_range *prange, unsigned long *bitmap,
185 		  unsigned long offset, unsigned long npages,
186 		  unsigned long *hmm_pfns)
187 {
188 	struct kfd_process *p;
189 	uint32_t gpuidx;
190 	int r;
191 
192 	p = container_of(prange->svms, struct kfd_process, svms);
193 
194 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
195 		struct kfd_process_device *pdd;
196 
197 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
198 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
199 		if (!pdd) {
200 			pr_debug("failed to find device idx %d\n", gpuidx);
201 			return -EINVAL;
202 		}
203 
204 		r = svm_range_dma_map_dev(pdd->dev->adev, prange, offset, npages,
205 					  hmm_pfns, gpuidx);
206 		if (r)
207 			break;
208 	}
209 
210 	return r;
211 }
212 
213 void svm_range_dma_unmap(struct device *dev, dma_addr_t *dma_addr,
214 			 unsigned long offset, unsigned long npages)
215 {
216 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
217 	int i;
218 
219 	if (!dma_addr)
220 		return;
221 
222 	for (i = offset; i < offset + npages; i++) {
223 		if (!svm_is_valid_dma_mapping_addr(dev, dma_addr[i]))
224 			continue;
225 		pr_debug_ratelimited("unmap 0x%llx\n", dma_addr[i] >> PAGE_SHIFT);
226 		dma_unmap_page(dev, dma_addr[i], PAGE_SIZE, dir);
227 		dma_addr[i] = 0;
228 	}
229 }
230 
231 void svm_range_free_dma_mappings(struct svm_range *prange)
232 {
233 	struct kfd_process_device *pdd;
234 	dma_addr_t *dma_addr;
235 	struct device *dev;
236 	struct kfd_process *p;
237 	uint32_t gpuidx;
238 
239 	p = container_of(prange->svms, struct kfd_process, svms);
240 
241 	for (gpuidx = 0; gpuidx < MAX_GPU_INSTANCE; gpuidx++) {
242 		dma_addr = prange->dma_addr[gpuidx];
243 		if (!dma_addr)
244 			continue;
245 
246 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
247 		if (!pdd) {
248 			pr_debug("failed to find device idx %d\n", gpuidx);
249 			continue;
250 		}
251 		dev = &pdd->dev->pdev->dev;
252 		svm_range_dma_unmap(dev, dma_addr, 0, prange->npages);
253 		kvfree(dma_addr);
254 		prange->dma_addr[gpuidx] = NULL;
255 	}
256 }
257 
258 static void svm_range_free(struct svm_range *prange)
259 {
260 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms, prange,
261 		 prange->start, prange->last);
262 
263 	svm_range_vram_node_free(prange);
264 	svm_range_free_dma_mappings(prange);
265 	mutex_destroy(&prange->lock);
266 	mutex_destroy(&prange->migrate_mutex);
267 	kfree(prange);
268 }
269 
270 static void
271 svm_range_set_default_attributes(int32_t *location, int32_t *prefetch_loc,
272 				 uint8_t *granularity, uint32_t *flags)
273 {
274 	*location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
275 	*prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
276 	*granularity = 9;
277 	*flags =
278 		KFD_IOCTL_SVM_FLAG_HOST_ACCESS | KFD_IOCTL_SVM_FLAG_COHERENT;
279 }
280 
281 static struct
282 svm_range *svm_range_new(struct svm_range_list *svms, uint64_t start,
283 			 uint64_t last)
284 {
285 	uint64_t size = last - start + 1;
286 	struct svm_range *prange;
287 	struct kfd_process *p;
288 
289 	prange = kzalloc(sizeof(*prange), GFP_KERNEL);
290 	if (!prange)
291 		return NULL;
292 	prange->npages = size;
293 	prange->svms = svms;
294 	prange->start = start;
295 	prange->last = last;
296 	INIT_LIST_HEAD(&prange->list);
297 	INIT_LIST_HEAD(&prange->update_list);
298 	INIT_LIST_HEAD(&prange->remove_list);
299 	INIT_LIST_HEAD(&prange->insert_list);
300 	INIT_LIST_HEAD(&prange->svm_bo_list);
301 	INIT_LIST_HEAD(&prange->deferred_list);
302 	INIT_LIST_HEAD(&prange->child_list);
303 	atomic_set(&prange->invalid, 0);
304 	prange->validate_timestamp = 0;
305 	mutex_init(&prange->migrate_mutex);
306 	mutex_init(&prange->lock);
307 
308 	p = container_of(svms, struct kfd_process, svms);
309 	if (p->xnack_enabled)
310 		bitmap_copy(prange->bitmap_access, svms->bitmap_supported,
311 			    MAX_GPU_INSTANCE);
312 
313 	svm_range_set_default_attributes(&prange->preferred_loc,
314 					 &prange->prefetch_loc,
315 					 &prange->granularity, &prange->flags);
316 
317 	pr_debug("svms 0x%p [0x%llx 0x%llx]\n", svms, start, last);
318 
319 	return prange;
320 }
321 
322 static bool svm_bo_ref_unless_zero(struct svm_range_bo *svm_bo)
323 {
324 	if (!svm_bo || !kref_get_unless_zero(&svm_bo->kref))
325 		return false;
326 
327 	return true;
328 }
329 
330 static void svm_range_bo_release(struct kref *kref)
331 {
332 	struct svm_range_bo *svm_bo;
333 
334 	svm_bo = container_of(kref, struct svm_range_bo, kref);
335 	spin_lock(&svm_bo->list_lock);
336 	while (!list_empty(&svm_bo->range_list)) {
337 		struct svm_range *prange =
338 				list_first_entry(&svm_bo->range_list,
339 						struct svm_range, svm_bo_list);
340 		/* list_del_init tells a concurrent svm_range_vram_node_new when
341 		 * it's safe to reuse the svm_bo pointer and svm_bo_list head.
342 		 */
343 		list_del_init(&prange->svm_bo_list);
344 		spin_unlock(&svm_bo->list_lock);
345 
346 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
347 			 prange->start, prange->last);
348 		mutex_lock(&prange->lock);
349 		prange->svm_bo = NULL;
350 		mutex_unlock(&prange->lock);
351 
352 		spin_lock(&svm_bo->list_lock);
353 	}
354 	spin_unlock(&svm_bo->list_lock);
355 	if (!dma_fence_is_signaled(&svm_bo->eviction_fence->base)) {
356 		/* We're not in the eviction worker.
357 		 * Signal the fence and synchronize with any
358 		 * pending eviction work.
359 		 */
360 		dma_fence_signal(&svm_bo->eviction_fence->base);
361 		cancel_work_sync(&svm_bo->eviction_work);
362 	}
363 	dma_fence_put(&svm_bo->eviction_fence->base);
364 	amdgpu_bo_unref(&svm_bo->bo);
365 	kfree(svm_bo);
366 }
367 
368 void svm_range_bo_unref(struct svm_range_bo *svm_bo)
369 {
370 	if (!svm_bo)
371 		return;
372 
373 	kref_put(&svm_bo->kref, svm_range_bo_release);
374 }
375 
376 static bool
377 svm_range_validate_svm_bo(struct amdgpu_device *adev, struct svm_range *prange)
378 {
379 	struct amdgpu_device *bo_adev;
380 
381 	mutex_lock(&prange->lock);
382 	if (!prange->svm_bo) {
383 		mutex_unlock(&prange->lock);
384 		return false;
385 	}
386 	if (prange->ttm_res) {
387 		/* We still have a reference, all is well */
388 		mutex_unlock(&prange->lock);
389 		return true;
390 	}
391 	if (svm_bo_ref_unless_zero(prange->svm_bo)) {
392 		/*
393 		 * Migrate from GPU to GPU, remove range from source bo_adev
394 		 * svm_bo range list, and return false to allocate svm_bo from
395 		 * destination adev.
396 		 */
397 		bo_adev = amdgpu_ttm_adev(prange->svm_bo->bo->tbo.bdev);
398 		if (bo_adev != adev) {
399 			mutex_unlock(&prange->lock);
400 
401 			spin_lock(&prange->svm_bo->list_lock);
402 			list_del_init(&prange->svm_bo_list);
403 			spin_unlock(&prange->svm_bo->list_lock);
404 
405 			svm_range_bo_unref(prange->svm_bo);
406 			return false;
407 		}
408 		if (READ_ONCE(prange->svm_bo->evicting)) {
409 			struct dma_fence *f;
410 			struct svm_range_bo *svm_bo;
411 			/* The BO is getting evicted,
412 			 * we need to get a new one
413 			 */
414 			mutex_unlock(&prange->lock);
415 			svm_bo = prange->svm_bo;
416 			f = dma_fence_get(&svm_bo->eviction_fence->base);
417 			svm_range_bo_unref(prange->svm_bo);
418 			/* wait for the fence to avoid long spin-loop
419 			 * at list_empty_careful
420 			 */
421 			dma_fence_wait(f, false);
422 			dma_fence_put(f);
423 		} else {
424 			/* The BO was still around and we got
425 			 * a new reference to it
426 			 */
427 			mutex_unlock(&prange->lock);
428 			pr_debug("reuse old bo svms 0x%p [0x%lx 0x%lx]\n",
429 				 prange->svms, prange->start, prange->last);
430 
431 			prange->ttm_res = prange->svm_bo->bo->tbo.resource;
432 			return true;
433 		}
434 
435 	} else {
436 		mutex_unlock(&prange->lock);
437 	}
438 
439 	/* We need a new svm_bo. Spin-loop to wait for concurrent
440 	 * svm_range_bo_release to finish removing this range from
441 	 * its range list. After this, it is safe to reuse the
442 	 * svm_bo pointer and svm_bo_list head.
443 	 */
444 	while (!list_empty_careful(&prange->svm_bo_list))
445 		;
446 
447 	return false;
448 }
449 
450 static struct svm_range_bo *svm_range_bo_new(void)
451 {
452 	struct svm_range_bo *svm_bo;
453 
454 	svm_bo = kzalloc(sizeof(*svm_bo), GFP_KERNEL);
455 	if (!svm_bo)
456 		return NULL;
457 
458 	kref_init(&svm_bo->kref);
459 	INIT_LIST_HEAD(&svm_bo->range_list);
460 	spin_lock_init(&svm_bo->list_lock);
461 
462 	return svm_bo;
463 }
464 
465 int
466 svm_range_vram_node_new(struct amdgpu_device *adev, struct svm_range *prange,
467 			bool clear)
468 {
469 	struct amdgpu_bo_param bp;
470 	struct svm_range_bo *svm_bo;
471 	struct amdgpu_bo_user *ubo;
472 	struct amdgpu_bo *bo;
473 	struct kfd_process *p;
474 	struct mm_struct *mm;
475 	int r;
476 
477 	p = container_of(prange->svms, struct kfd_process, svms);
478 	pr_debug("pasid: %x svms 0x%p [0x%lx 0x%lx]\n", p->pasid, prange->svms,
479 		 prange->start, prange->last);
480 
481 	if (svm_range_validate_svm_bo(adev, prange))
482 		return 0;
483 
484 	svm_bo = svm_range_bo_new();
485 	if (!svm_bo) {
486 		pr_debug("failed to alloc svm bo\n");
487 		return -ENOMEM;
488 	}
489 	mm = get_task_mm(p->lead_thread);
490 	if (!mm) {
491 		pr_debug("failed to get mm\n");
492 		kfree(svm_bo);
493 		return -ESRCH;
494 	}
495 	svm_bo->svms = prange->svms;
496 	svm_bo->eviction_fence =
497 		amdgpu_amdkfd_fence_create(dma_fence_context_alloc(1),
498 					   mm,
499 					   svm_bo);
500 	mmput(mm);
501 	INIT_WORK(&svm_bo->eviction_work, svm_range_evict_svm_bo_worker);
502 	svm_bo->evicting = 0;
503 	memset(&bp, 0, sizeof(bp));
504 	bp.size = prange->npages * PAGE_SIZE;
505 	bp.byte_align = PAGE_SIZE;
506 	bp.domain = AMDGPU_GEM_DOMAIN_VRAM;
507 	bp.flags = AMDGPU_GEM_CREATE_NO_CPU_ACCESS;
508 	bp.flags |= clear ? AMDGPU_GEM_CREATE_VRAM_CLEARED : 0;
509 	bp.flags |= AMDGPU_AMDKFD_CREATE_SVM_BO;
510 	bp.type = ttm_bo_type_device;
511 	bp.resv = NULL;
512 
513 	r = amdgpu_bo_create_user(adev, &bp, &ubo);
514 	if (r) {
515 		pr_debug("failed %d to create bo\n", r);
516 		goto create_bo_failed;
517 	}
518 	bo = &ubo->bo;
519 	r = amdgpu_bo_reserve(bo, true);
520 	if (r) {
521 		pr_debug("failed %d to reserve bo\n", r);
522 		goto reserve_bo_failed;
523 	}
524 
525 	r = dma_resv_reserve_shared(bo->tbo.base.resv, 1);
526 	if (r) {
527 		pr_debug("failed %d to reserve bo\n", r);
528 		amdgpu_bo_unreserve(bo);
529 		goto reserve_bo_failed;
530 	}
531 	amdgpu_bo_fence(bo, &svm_bo->eviction_fence->base, true);
532 
533 	amdgpu_bo_unreserve(bo);
534 
535 	svm_bo->bo = bo;
536 	prange->svm_bo = svm_bo;
537 	prange->ttm_res = bo->tbo.resource;
538 	prange->offset = 0;
539 
540 	spin_lock(&svm_bo->list_lock);
541 	list_add(&prange->svm_bo_list, &svm_bo->range_list);
542 	spin_unlock(&svm_bo->list_lock);
543 
544 	return 0;
545 
546 reserve_bo_failed:
547 	amdgpu_bo_unref(&bo);
548 create_bo_failed:
549 	dma_fence_put(&svm_bo->eviction_fence->base);
550 	kfree(svm_bo);
551 	prange->ttm_res = NULL;
552 
553 	return r;
554 }
555 
556 void svm_range_vram_node_free(struct svm_range *prange)
557 {
558 	svm_range_bo_unref(prange->svm_bo);
559 	prange->ttm_res = NULL;
560 }
561 
562 struct amdgpu_device *
563 svm_range_get_adev_by_id(struct svm_range *prange, uint32_t gpu_id)
564 {
565 	struct kfd_process_device *pdd;
566 	struct kfd_process *p;
567 	int32_t gpu_idx;
568 
569 	p = container_of(prange->svms, struct kfd_process, svms);
570 
571 	gpu_idx = kfd_process_gpuidx_from_gpuid(p, gpu_id);
572 	if (gpu_idx < 0) {
573 		pr_debug("failed to get device by id 0x%x\n", gpu_id);
574 		return NULL;
575 	}
576 	pdd = kfd_process_device_from_gpuidx(p, gpu_idx);
577 	if (!pdd) {
578 		pr_debug("failed to get device by idx 0x%x\n", gpu_idx);
579 		return NULL;
580 	}
581 
582 	return pdd->dev->adev;
583 }
584 
585 struct kfd_process_device *
586 svm_range_get_pdd_by_adev(struct svm_range *prange, struct amdgpu_device *adev)
587 {
588 	struct kfd_process *p;
589 	int32_t gpu_idx, gpuid;
590 	int r;
591 
592 	p = container_of(prange->svms, struct kfd_process, svms);
593 
594 	r = kfd_process_gpuid_from_adev(p, adev, &gpuid, &gpu_idx);
595 	if (r) {
596 		pr_debug("failed to get device id by adev %p\n", adev);
597 		return NULL;
598 	}
599 
600 	return kfd_process_device_from_gpuidx(p, gpu_idx);
601 }
602 
603 static int svm_range_bo_validate(void *param, struct amdgpu_bo *bo)
604 {
605 	struct ttm_operation_ctx ctx = { false, false };
606 
607 	amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_VRAM);
608 
609 	return ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
610 }
611 
612 static int
613 svm_range_check_attr(struct kfd_process *p,
614 		     uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
615 {
616 	uint32_t i;
617 
618 	for (i = 0; i < nattr; i++) {
619 		uint32_t val = attrs[i].value;
620 		int gpuidx = MAX_GPU_INSTANCE;
621 
622 		switch (attrs[i].type) {
623 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
624 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM &&
625 			    val != KFD_IOCTL_SVM_LOCATION_UNDEFINED)
626 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
627 			break;
628 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
629 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM)
630 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
631 			break;
632 		case KFD_IOCTL_SVM_ATTR_ACCESS:
633 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
634 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
635 			gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
636 			break;
637 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
638 			break;
639 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
640 			break;
641 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
642 			break;
643 		default:
644 			pr_debug("unknown attr type 0x%x\n", attrs[i].type);
645 			return -EINVAL;
646 		}
647 
648 		if (gpuidx < 0) {
649 			pr_debug("no GPU 0x%x found\n", val);
650 			return -EINVAL;
651 		} else if (gpuidx < MAX_GPU_INSTANCE &&
652 			   !test_bit(gpuidx, p->svms.bitmap_supported)) {
653 			pr_debug("GPU 0x%x not supported\n", val);
654 			return -EINVAL;
655 		}
656 	}
657 
658 	return 0;
659 }
660 
661 static void
662 svm_range_apply_attrs(struct kfd_process *p, struct svm_range *prange,
663 		      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
664 {
665 	uint32_t i;
666 	int gpuidx;
667 
668 	for (i = 0; i < nattr; i++) {
669 		switch (attrs[i].type) {
670 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
671 			prange->preferred_loc = attrs[i].value;
672 			break;
673 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
674 			prange->prefetch_loc = attrs[i].value;
675 			break;
676 		case KFD_IOCTL_SVM_ATTR_ACCESS:
677 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
678 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
679 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
680 							       attrs[i].value);
681 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
682 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
683 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
684 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
685 				bitmap_set(prange->bitmap_access, gpuidx, 1);
686 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
687 			} else {
688 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
689 				bitmap_set(prange->bitmap_aip, gpuidx, 1);
690 			}
691 			break;
692 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
693 			prange->flags |= attrs[i].value;
694 			break;
695 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
696 			prange->flags &= ~attrs[i].value;
697 			break;
698 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
699 			prange->granularity = attrs[i].value;
700 			break;
701 		default:
702 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
703 		}
704 	}
705 }
706 
707 /**
708  * svm_range_debug_dump - print all range information from svms
709  * @svms: svm range list header
710  *
711  * debug output svm range start, end, prefetch location from svms
712  * interval tree and link list
713  *
714  * Context: The caller must hold svms->lock
715  */
716 static void svm_range_debug_dump(struct svm_range_list *svms)
717 {
718 	struct interval_tree_node *node;
719 	struct svm_range *prange;
720 
721 	pr_debug("dump svms 0x%p list\n", svms);
722 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
723 
724 	list_for_each_entry(prange, &svms->list, list) {
725 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
726 			 prange, prange->start, prange->npages,
727 			 prange->start + prange->npages - 1,
728 			 prange->actual_loc);
729 	}
730 
731 	pr_debug("dump svms 0x%p interval tree\n", svms);
732 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
733 	node = interval_tree_iter_first(&svms->objects, 0, ~0ULL);
734 	while (node) {
735 		prange = container_of(node, struct svm_range, it_node);
736 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
737 			 prange, prange->start, prange->npages,
738 			 prange->start + prange->npages - 1,
739 			 prange->actual_loc);
740 		node = interval_tree_iter_next(node, 0, ~0ULL);
741 	}
742 }
743 
744 static bool
745 svm_range_is_same_attrs(struct svm_range *old, struct svm_range *new)
746 {
747 	return (old->prefetch_loc == new->prefetch_loc &&
748 		old->flags == new->flags &&
749 		old->granularity == new->granularity);
750 }
751 
752 static int
753 svm_range_split_array(void *ppnew, void *ppold, size_t size,
754 		      uint64_t old_start, uint64_t old_n,
755 		      uint64_t new_start, uint64_t new_n)
756 {
757 	unsigned char *new, *old, *pold;
758 	uint64_t d;
759 
760 	if (!ppold)
761 		return 0;
762 	pold = *(unsigned char **)ppold;
763 	if (!pold)
764 		return 0;
765 
766 	new = kvmalloc_array(new_n, size, GFP_KERNEL);
767 	if (!new)
768 		return -ENOMEM;
769 
770 	d = (new_start - old_start) * size;
771 	memcpy(new, pold + d, new_n * size);
772 
773 	old = kvmalloc_array(old_n, size, GFP_KERNEL);
774 	if (!old) {
775 		kvfree(new);
776 		return -ENOMEM;
777 	}
778 
779 	d = (new_start == old_start) ? new_n * size : 0;
780 	memcpy(old, pold + d, old_n * size);
781 
782 	kvfree(pold);
783 	*(void **)ppold = old;
784 	*(void **)ppnew = new;
785 
786 	return 0;
787 }
788 
789 static int
790 svm_range_split_pages(struct svm_range *new, struct svm_range *old,
791 		      uint64_t start, uint64_t last)
792 {
793 	uint64_t npages = last - start + 1;
794 	int i, r;
795 
796 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
797 		r = svm_range_split_array(&new->dma_addr[i], &old->dma_addr[i],
798 					  sizeof(*old->dma_addr[i]), old->start,
799 					  npages, new->start, new->npages);
800 		if (r)
801 			return r;
802 	}
803 
804 	return 0;
805 }
806 
807 static int
808 svm_range_split_nodes(struct svm_range *new, struct svm_range *old,
809 		      uint64_t start, uint64_t last)
810 {
811 	uint64_t npages = last - start + 1;
812 
813 	pr_debug("svms 0x%p new prange 0x%p start 0x%lx [0x%llx 0x%llx]\n",
814 		 new->svms, new, new->start, start, last);
815 
816 	if (new->start == old->start) {
817 		new->offset = old->offset;
818 		old->offset += new->npages;
819 	} else {
820 		new->offset = old->offset + npages;
821 	}
822 
823 	new->svm_bo = svm_range_bo_ref(old->svm_bo);
824 	new->ttm_res = old->ttm_res;
825 
826 	spin_lock(&new->svm_bo->list_lock);
827 	list_add(&new->svm_bo_list, &new->svm_bo->range_list);
828 	spin_unlock(&new->svm_bo->list_lock);
829 
830 	return 0;
831 }
832 
833 /**
834  * svm_range_split_adjust - split range and adjust
835  *
836  * @new: new range
837  * @old: the old range
838  * @start: the old range adjust to start address in pages
839  * @last: the old range adjust to last address in pages
840  *
841  * Copy system memory dma_addr or vram ttm_res in old range to new
842  * range from new_start up to size new->npages, the remaining old range is from
843  * start to last
844  *
845  * Return:
846  * 0 - OK, -ENOMEM - out of memory
847  */
848 static int
849 svm_range_split_adjust(struct svm_range *new, struct svm_range *old,
850 		      uint64_t start, uint64_t last)
851 {
852 	int r;
853 
854 	pr_debug("svms 0x%p new 0x%lx old [0x%lx 0x%lx] => [0x%llx 0x%llx]\n",
855 		 new->svms, new->start, old->start, old->last, start, last);
856 
857 	if (new->start < old->start ||
858 	    new->last > old->last) {
859 		WARN_ONCE(1, "invalid new range start or last\n");
860 		return -EINVAL;
861 	}
862 
863 	r = svm_range_split_pages(new, old, start, last);
864 	if (r)
865 		return r;
866 
867 	if (old->actual_loc && old->ttm_res) {
868 		r = svm_range_split_nodes(new, old, start, last);
869 		if (r)
870 			return r;
871 	}
872 
873 	old->npages = last - start + 1;
874 	old->start = start;
875 	old->last = last;
876 	new->flags = old->flags;
877 	new->preferred_loc = old->preferred_loc;
878 	new->prefetch_loc = old->prefetch_loc;
879 	new->actual_loc = old->actual_loc;
880 	new->granularity = old->granularity;
881 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
882 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
883 
884 	return 0;
885 }
886 
887 /**
888  * svm_range_split - split a range in 2 ranges
889  *
890  * @prange: the svm range to split
891  * @start: the remaining range start address in pages
892  * @last: the remaining range last address in pages
893  * @new: the result new range generated
894  *
895  * Two cases only:
896  * case 1: if start == prange->start
897  *         prange ==> prange[start, last]
898  *         new range [last + 1, prange->last]
899  *
900  * case 2: if last == prange->last
901  *         prange ==> prange[start, last]
902  *         new range [prange->start, start - 1]
903  *
904  * Return:
905  * 0 - OK, -ENOMEM - out of memory, -EINVAL - invalid start, last
906  */
907 static int
908 svm_range_split(struct svm_range *prange, uint64_t start, uint64_t last,
909 		struct svm_range **new)
910 {
911 	uint64_t old_start = prange->start;
912 	uint64_t old_last = prange->last;
913 	struct svm_range_list *svms;
914 	int r = 0;
915 
916 	pr_debug("svms 0x%p [0x%llx 0x%llx] to [0x%llx 0x%llx]\n", prange->svms,
917 		 old_start, old_last, start, last);
918 
919 	if (old_start != start && old_last != last)
920 		return -EINVAL;
921 	if (start < old_start || last > old_last)
922 		return -EINVAL;
923 
924 	svms = prange->svms;
925 	if (old_start == start)
926 		*new = svm_range_new(svms, last + 1, old_last);
927 	else
928 		*new = svm_range_new(svms, old_start, start - 1);
929 	if (!*new)
930 		return -ENOMEM;
931 
932 	r = svm_range_split_adjust(*new, prange, start, last);
933 	if (r) {
934 		pr_debug("failed %d split [0x%llx 0x%llx] to [0x%llx 0x%llx]\n",
935 			 r, old_start, old_last, start, last);
936 		svm_range_free(*new);
937 		*new = NULL;
938 	}
939 
940 	return r;
941 }
942 
943 static int
944 svm_range_split_tail(struct svm_range *prange, struct svm_range *new,
945 		     uint64_t new_last, struct list_head *insert_list)
946 {
947 	struct svm_range *tail;
948 	int r = svm_range_split(prange, prange->start, new_last, &tail);
949 
950 	if (!r)
951 		list_add(&tail->insert_list, insert_list);
952 	return r;
953 }
954 
955 static int
956 svm_range_split_head(struct svm_range *prange, struct svm_range *new,
957 		     uint64_t new_start, struct list_head *insert_list)
958 {
959 	struct svm_range *head;
960 	int r = svm_range_split(prange, new_start, prange->last, &head);
961 
962 	if (!r)
963 		list_add(&head->insert_list, insert_list);
964 	return r;
965 }
966 
967 static void
968 svm_range_add_child(struct svm_range *prange, struct mm_struct *mm,
969 		    struct svm_range *pchild, enum svm_work_list_ops op)
970 {
971 	pr_debug("add child 0x%p [0x%lx 0x%lx] to prange 0x%p child list %d\n",
972 		 pchild, pchild->start, pchild->last, prange, op);
973 
974 	pchild->work_item.mm = mm;
975 	pchild->work_item.op = op;
976 	list_add_tail(&pchild->child_list, &prange->child_list);
977 }
978 
979 /**
980  * svm_range_split_by_granularity - collect ranges within granularity boundary
981  *
982  * @p: the process with svms list
983  * @mm: mm structure
984  * @addr: the vm fault address in pages, to split the prange
985  * @parent: parent range if prange is from child list
986  * @prange: prange to split
987  *
988  * Trims @prange to be a single aligned block of prange->granularity if
989  * possible. The head and tail are added to the child_list in @parent.
990  *
991  * Context: caller must hold mmap_read_lock and prange->lock
992  *
993  * Return:
994  * 0 - OK, otherwise error code
995  */
996 int
997 svm_range_split_by_granularity(struct kfd_process *p, struct mm_struct *mm,
998 			       unsigned long addr, struct svm_range *parent,
999 			       struct svm_range *prange)
1000 {
1001 	struct svm_range *head, *tail;
1002 	unsigned long start, last, size;
1003 	int r;
1004 
1005 	/* Align splited range start and size to granularity size, then a single
1006 	 * PTE will be used for whole range, this reduces the number of PTE
1007 	 * updated and the L1 TLB space used for translation.
1008 	 */
1009 	size = 1UL << prange->granularity;
1010 	start = ALIGN_DOWN(addr, size);
1011 	last = ALIGN(addr + 1, size) - 1;
1012 
1013 	pr_debug("svms 0x%p split [0x%lx 0x%lx] to [0x%lx 0x%lx] size 0x%lx\n",
1014 		 prange->svms, prange->start, prange->last, start, last, size);
1015 
1016 	if (start > prange->start) {
1017 		r = svm_range_split(prange, start, prange->last, &head);
1018 		if (r)
1019 			return r;
1020 		svm_range_add_child(parent, mm, head, SVM_OP_ADD_RANGE);
1021 	}
1022 
1023 	if (last < prange->last) {
1024 		r = svm_range_split(prange, prange->start, last, &tail);
1025 		if (r)
1026 			return r;
1027 		svm_range_add_child(parent, mm, tail, SVM_OP_ADD_RANGE);
1028 	}
1029 
1030 	/* xnack on, update mapping on GPUs with ACCESS_IN_PLACE */
1031 	if (p->xnack_enabled && prange->work_item.op == SVM_OP_ADD_RANGE) {
1032 		prange->work_item.op = SVM_OP_ADD_RANGE_AND_MAP;
1033 		pr_debug("change prange 0x%p [0x%lx 0x%lx] op %d\n",
1034 			 prange, prange->start, prange->last,
1035 			 SVM_OP_ADD_RANGE_AND_MAP);
1036 	}
1037 	return 0;
1038 }
1039 
1040 static uint64_t
1041 svm_range_get_pte_flags(struct amdgpu_device *adev, struct svm_range *prange,
1042 			int domain)
1043 {
1044 	struct amdgpu_device *bo_adev;
1045 	uint32_t flags = prange->flags;
1046 	uint32_t mapping_flags = 0;
1047 	uint64_t pte_flags;
1048 	bool snoop = (domain != SVM_RANGE_VRAM_DOMAIN);
1049 	bool coherent = flags & KFD_IOCTL_SVM_FLAG_COHERENT;
1050 
1051 	if (domain == SVM_RANGE_VRAM_DOMAIN)
1052 		bo_adev = amdgpu_ttm_adev(prange->svm_bo->bo->tbo.bdev);
1053 
1054 	switch (KFD_GC_VERSION(adev->kfd.dev)) {
1055 	case IP_VERSION(9, 4, 1):
1056 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1057 			if (bo_adev == adev) {
1058 				mapping_flags |= coherent ?
1059 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1060 			} else {
1061 				mapping_flags |= coherent ?
1062 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1063 				if (amdgpu_xgmi_same_hive(adev, bo_adev))
1064 					snoop = true;
1065 			}
1066 		} else {
1067 			mapping_flags |= coherent ?
1068 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1069 		}
1070 		break;
1071 	case IP_VERSION(9, 4, 2):
1072 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1073 			if (bo_adev == adev) {
1074 				mapping_flags |= coherent ?
1075 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1076 				if (adev->gmc.xgmi.connected_to_cpu)
1077 					snoop = true;
1078 			} else {
1079 				mapping_flags |= coherent ?
1080 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1081 				if (amdgpu_xgmi_same_hive(adev, bo_adev))
1082 					snoop = true;
1083 			}
1084 		} else {
1085 			mapping_flags |= coherent ?
1086 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1087 		}
1088 		break;
1089 	default:
1090 		mapping_flags |= coherent ?
1091 			AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1092 	}
1093 
1094 	mapping_flags |= AMDGPU_VM_PAGE_READABLE | AMDGPU_VM_PAGE_WRITEABLE;
1095 
1096 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_RO)
1097 		mapping_flags &= ~AMDGPU_VM_PAGE_WRITEABLE;
1098 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_EXEC)
1099 		mapping_flags |= AMDGPU_VM_PAGE_EXECUTABLE;
1100 
1101 	pte_flags = AMDGPU_PTE_VALID;
1102 	pte_flags |= (domain == SVM_RANGE_VRAM_DOMAIN) ? 0 : AMDGPU_PTE_SYSTEM;
1103 	pte_flags |= snoop ? AMDGPU_PTE_SNOOPED : 0;
1104 
1105 	pte_flags |= amdgpu_gem_va_map_flags(adev, mapping_flags);
1106 	return pte_flags;
1107 }
1108 
1109 static int
1110 svm_range_unmap_from_gpu(struct amdgpu_device *adev, struct amdgpu_vm *vm,
1111 			 uint64_t start, uint64_t last,
1112 			 struct dma_fence **fence)
1113 {
1114 	uint64_t init_pte_value = 0;
1115 
1116 	pr_debug("[0x%llx 0x%llx]\n", start, last);
1117 
1118 	return amdgpu_vm_bo_update_mapping(adev, adev, vm, false, true, NULL,
1119 					   start, last, init_pte_value, 0,
1120 					   NULL, NULL, fence, NULL);
1121 }
1122 
1123 static int
1124 svm_range_unmap_from_gpus(struct svm_range *prange, unsigned long start,
1125 			  unsigned long last)
1126 {
1127 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1128 	struct kfd_process_device *pdd;
1129 	struct dma_fence *fence = NULL;
1130 	struct kfd_process *p;
1131 	uint32_t gpuidx;
1132 	int r = 0;
1133 
1134 	bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
1135 		  MAX_GPU_INSTANCE);
1136 	p = container_of(prange->svms, struct kfd_process, svms);
1137 
1138 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1139 		pr_debug("unmap from gpu idx 0x%x\n", gpuidx);
1140 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1141 		if (!pdd) {
1142 			pr_debug("failed to find device idx %d\n", gpuidx);
1143 			return -EINVAL;
1144 		}
1145 
1146 		r = svm_range_unmap_from_gpu(pdd->dev->adev,
1147 					     drm_priv_to_vm(pdd->drm_priv),
1148 					     start, last, &fence);
1149 		if (r)
1150 			break;
1151 
1152 		if (fence) {
1153 			r = dma_fence_wait(fence, false);
1154 			dma_fence_put(fence);
1155 			fence = NULL;
1156 			if (r)
1157 				break;
1158 		}
1159 		amdgpu_amdkfd_flush_gpu_tlb_pasid(pdd->dev->adev,
1160 					p->pasid, TLB_FLUSH_HEAVYWEIGHT);
1161 	}
1162 
1163 	return r;
1164 }
1165 
1166 static int
1167 svm_range_map_to_gpu(struct amdgpu_device *adev, struct amdgpu_vm *vm,
1168 		     struct svm_range *prange, unsigned long offset,
1169 		     unsigned long npages, bool readonly, dma_addr_t *dma_addr,
1170 		     struct amdgpu_device *bo_adev, struct dma_fence **fence)
1171 {
1172 	struct amdgpu_bo_va bo_va;
1173 	bool table_freed = false;
1174 	uint64_t pte_flags;
1175 	unsigned long last_start;
1176 	int last_domain;
1177 	int r = 0;
1178 	int64_t i, j;
1179 
1180 	last_start = prange->start + offset;
1181 
1182 	pr_debug("svms 0x%p [0x%lx 0x%lx] readonly %d\n", prange->svms,
1183 		 last_start, last_start + npages - 1, readonly);
1184 
1185 	if (prange->svm_bo && prange->ttm_res)
1186 		bo_va.is_xgmi = amdgpu_xgmi_same_hive(adev, bo_adev);
1187 
1188 	for (i = offset; i < offset + npages; i++) {
1189 		last_domain = dma_addr[i] & SVM_RANGE_VRAM_DOMAIN;
1190 		dma_addr[i] &= ~SVM_RANGE_VRAM_DOMAIN;
1191 
1192 		/* Collect all pages in the same address range and memory domain
1193 		 * that can be mapped with a single call to update mapping.
1194 		 */
1195 		if (i < offset + npages - 1 &&
1196 		    last_domain == (dma_addr[i + 1] & SVM_RANGE_VRAM_DOMAIN))
1197 			continue;
1198 
1199 		pr_debug("Mapping range [0x%lx 0x%llx] on domain: %s\n",
1200 			 last_start, prange->start + i, last_domain ? "GPU" : "CPU");
1201 
1202 		pte_flags = svm_range_get_pte_flags(adev, prange, last_domain);
1203 		if (readonly)
1204 			pte_flags &= ~AMDGPU_PTE_WRITEABLE;
1205 
1206 		pr_debug("svms 0x%p map [0x%lx 0x%llx] vram %d PTE 0x%llx\n",
1207 			 prange->svms, last_start, prange->start + i,
1208 			 (last_domain == SVM_RANGE_VRAM_DOMAIN) ? 1 : 0,
1209 			 pte_flags);
1210 
1211 		r = amdgpu_vm_bo_update_mapping(adev, bo_adev, vm, false, false,
1212 						NULL, last_start,
1213 						prange->start + i, pte_flags,
1214 						last_start - prange->start,
1215 						NULL, dma_addr,
1216 						&vm->last_update,
1217 						&table_freed);
1218 
1219 		for (j = last_start - prange->start; j <= i; j++)
1220 			dma_addr[j] |= last_domain;
1221 
1222 		if (r) {
1223 			pr_debug("failed %d to map to gpu 0x%lx\n", r, prange->start);
1224 			goto out;
1225 		}
1226 		last_start = prange->start + i + 1;
1227 	}
1228 
1229 	r = amdgpu_vm_update_pdes(adev, vm, false);
1230 	if (r) {
1231 		pr_debug("failed %d to update directories 0x%lx\n", r,
1232 			 prange->start);
1233 		goto out;
1234 	}
1235 
1236 	if (fence)
1237 		*fence = dma_fence_get(vm->last_update);
1238 
1239 	if (table_freed) {
1240 		struct kfd_process *p;
1241 
1242 		p = container_of(prange->svms, struct kfd_process, svms);
1243 		amdgpu_amdkfd_flush_gpu_tlb_pasid(adev, p->pasid, TLB_FLUSH_LEGACY);
1244 	}
1245 out:
1246 	return r;
1247 }
1248 
1249 static int
1250 svm_range_map_to_gpus(struct svm_range *prange, unsigned long offset,
1251 		      unsigned long npages, bool readonly,
1252 		      unsigned long *bitmap, bool wait)
1253 {
1254 	struct kfd_process_device *pdd;
1255 	struct amdgpu_device *bo_adev;
1256 	struct kfd_process *p;
1257 	struct dma_fence *fence = NULL;
1258 	uint32_t gpuidx;
1259 	int r = 0;
1260 
1261 	if (prange->svm_bo && prange->ttm_res)
1262 		bo_adev = amdgpu_ttm_adev(prange->svm_bo->bo->tbo.bdev);
1263 	else
1264 		bo_adev = NULL;
1265 
1266 	p = container_of(prange->svms, struct kfd_process, svms);
1267 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1268 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
1269 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1270 		if (!pdd) {
1271 			pr_debug("failed to find device idx %d\n", gpuidx);
1272 			return -EINVAL;
1273 		}
1274 
1275 		pdd = kfd_bind_process_to_device(pdd->dev, p);
1276 		if (IS_ERR(pdd))
1277 			return -EINVAL;
1278 
1279 		if (bo_adev && pdd->dev->adev != bo_adev &&
1280 		    !amdgpu_xgmi_same_hive(pdd->dev->adev, bo_adev)) {
1281 			pr_debug("cannot map to device idx %d\n", gpuidx);
1282 			continue;
1283 		}
1284 
1285 		r = svm_range_map_to_gpu(pdd->dev->adev, drm_priv_to_vm(pdd->drm_priv),
1286 					 prange, offset, npages, readonly,
1287 					 prange->dma_addr[gpuidx],
1288 					 bo_adev, wait ? &fence : NULL);
1289 		if (r)
1290 			break;
1291 
1292 		if (fence) {
1293 			r = dma_fence_wait(fence, false);
1294 			dma_fence_put(fence);
1295 			fence = NULL;
1296 			if (r) {
1297 				pr_debug("failed %d to dma fence wait\n", r);
1298 				break;
1299 			}
1300 		}
1301 	}
1302 
1303 	return r;
1304 }
1305 
1306 struct svm_validate_context {
1307 	struct kfd_process *process;
1308 	struct svm_range *prange;
1309 	bool intr;
1310 	unsigned long bitmap[MAX_GPU_INSTANCE];
1311 	struct ttm_validate_buffer tv[MAX_GPU_INSTANCE];
1312 	struct list_head validate_list;
1313 	struct ww_acquire_ctx ticket;
1314 };
1315 
1316 static int svm_range_reserve_bos(struct svm_validate_context *ctx)
1317 {
1318 	struct kfd_process_device *pdd;
1319 	struct amdgpu_vm *vm;
1320 	uint32_t gpuidx;
1321 	int r;
1322 
1323 	INIT_LIST_HEAD(&ctx->validate_list);
1324 	for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1325 		pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1326 		if (!pdd) {
1327 			pr_debug("failed to find device idx %d\n", gpuidx);
1328 			return -EINVAL;
1329 		}
1330 		vm = drm_priv_to_vm(pdd->drm_priv);
1331 
1332 		ctx->tv[gpuidx].bo = &vm->root.bo->tbo;
1333 		ctx->tv[gpuidx].num_shared = 4;
1334 		list_add(&ctx->tv[gpuidx].head, &ctx->validate_list);
1335 	}
1336 
1337 	r = ttm_eu_reserve_buffers(&ctx->ticket, &ctx->validate_list,
1338 				   ctx->intr, NULL);
1339 	if (r) {
1340 		pr_debug("failed %d to reserve bo\n", r);
1341 		return r;
1342 	}
1343 
1344 	for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1345 		pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1346 		if (!pdd) {
1347 			pr_debug("failed to find device idx %d\n", gpuidx);
1348 			r = -EINVAL;
1349 			goto unreserve_out;
1350 		}
1351 
1352 		r = amdgpu_vm_validate_pt_bos(pdd->dev->adev,
1353 					      drm_priv_to_vm(pdd->drm_priv),
1354 					      svm_range_bo_validate, NULL);
1355 		if (r) {
1356 			pr_debug("failed %d validate pt bos\n", r);
1357 			goto unreserve_out;
1358 		}
1359 	}
1360 
1361 	return 0;
1362 
1363 unreserve_out:
1364 	ttm_eu_backoff_reservation(&ctx->ticket, &ctx->validate_list);
1365 	return r;
1366 }
1367 
1368 static void svm_range_unreserve_bos(struct svm_validate_context *ctx)
1369 {
1370 	ttm_eu_backoff_reservation(&ctx->ticket, &ctx->validate_list);
1371 }
1372 
1373 static void *kfd_svm_page_owner(struct kfd_process *p, int32_t gpuidx)
1374 {
1375 	struct kfd_process_device *pdd;
1376 
1377 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1378 
1379 	return SVM_ADEV_PGMAP_OWNER(pdd->dev->adev);
1380 }
1381 
1382 /*
1383  * Validation+GPU mapping with concurrent invalidation (MMU notifiers)
1384  *
1385  * To prevent concurrent destruction or change of range attributes, the
1386  * svm_read_lock must be held. The caller must not hold the svm_write_lock
1387  * because that would block concurrent evictions and lead to deadlocks. To
1388  * serialize concurrent migrations or validations of the same range, the
1389  * prange->migrate_mutex must be held.
1390  *
1391  * For VRAM ranges, the SVM BO must be allocated and valid (protected by its
1392  * eviction fence.
1393  *
1394  * The following sequence ensures race-free validation and GPU mapping:
1395  *
1396  * 1. Reserve page table (and SVM BO if range is in VRAM)
1397  * 2. hmm_range_fault to get page addresses (if system memory)
1398  * 3. DMA-map pages (if system memory)
1399  * 4-a. Take notifier lock
1400  * 4-b. Check that pages still valid (mmu_interval_read_retry)
1401  * 4-c. Check that the range was not split or otherwise invalidated
1402  * 4-d. Update GPU page table
1403  * 4.e. Release notifier lock
1404  * 5. Release page table (and SVM BO) reservation
1405  */
1406 static int svm_range_validate_and_map(struct mm_struct *mm,
1407 				      struct svm_range *prange,
1408 				      int32_t gpuidx, bool intr, bool wait)
1409 {
1410 	struct svm_validate_context ctx;
1411 	unsigned long start, end, addr;
1412 	struct kfd_process *p;
1413 	void *owner;
1414 	int32_t idx;
1415 	int r = 0;
1416 
1417 	ctx.process = container_of(prange->svms, struct kfd_process, svms);
1418 	ctx.prange = prange;
1419 	ctx.intr = intr;
1420 
1421 	if (gpuidx < MAX_GPU_INSTANCE) {
1422 		bitmap_zero(ctx.bitmap, MAX_GPU_INSTANCE);
1423 		bitmap_set(ctx.bitmap, gpuidx, 1);
1424 	} else if (ctx.process->xnack_enabled) {
1425 		bitmap_copy(ctx.bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
1426 
1427 		/* If prefetch range to GPU, or GPU retry fault migrate range to
1428 		 * GPU, which has ACCESS attribute to the range, create mapping
1429 		 * on that GPU.
1430 		 */
1431 		if (prange->actual_loc) {
1432 			gpuidx = kfd_process_gpuidx_from_gpuid(ctx.process,
1433 							prange->actual_loc);
1434 			if (gpuidx < 0) {
1435 				WARN_ONCE(1, "failed get device by id 0x%x\n",
1436 					 prange->actual_loc);
1437 				return -EINVAL;
1438 			}
1439 			if (test_bit(gpuidx, prange->bitmap_access))
1440 				bitmap_set(ctx.bitmap, gpuidx, 1);
1441 		}
1442 	} else {
1443 		bitmap_or(ctx.bitmap, prange->bitmap_access,
1444 			  prange->bitmap_aip, MAX_GPU_INSTANCE);
1445 	}
1446 
1447 	if (bitmap_empty(ctx.bitmap, MAX_GPU_INSTANCE))
1448 		return 0;
1449 
1450 	if (prange->actual_loc && !prange->ttm_res) {
1451 		/* This should never happen. actual_loc gets set by
1452 		 * svm_migrate_ram_to_vram after allocating a BO.
1453 		 */
1454 		WARN_ONCE(1, "VRAM BO missing during validation\n");
1455 		return -EINVAL;
1456 	}
1457 
1458 	svm_range_reserve_bos(&ctx);
1459 
1460 	p = container_of(prange->svms, struct kfd_process, svms);
1461 	owner = kfd_svm_page_owner(p, find_first_bit(ctx.bitmap,
1462 						MAX_GPU_INSTANCE));
1463 	for_each_set_bit(idx, ctx.bitmap, MAX_GPU_INSTANCE) {
1464 		if (kfd_svm_page_owner(p, idx) != owner) {
1465 			owner = NULL;
1466 			break;
1467 		}
1468 	}
1469 
1470 	start = prange->start << PAGE_SHIFT;
1471 	end = (prange->last + 1) << PAGE_SHIFT;
1472 	for (addr = start; addr < end && !r; ) {
1473 		struct hmm_range *hmm_range;
1474 		struct vm_area_struct *vma;
1475 		unsigned long next;
1476 		unsigned long offset;
1477 		unsigned long npages;
1478 		bool readonly;
1479 
1480 		vma = find_vma(mm, addr);
1481 		if (!vma || addr < vma->vm_start) {
1482 			r = -EFAULT;
1483 			goto unreserve_out;
1484 		}
1485 		readonly = !(vma->vm_flags & VM_WRITE);
1486 
1487 		next = min(vma->vm_end, end);
1488 		npages = (next - addr) >> PAGE_SHIFT;
1489 		WRITE_ONCE(p->svms.faulting_task, current);
1490 		r = amdgpu_hmm_range_get_pages(&prange->notifier, mm, NULL,
1491 					       addr, npages, &hmm_range,
1492 					       readonly, true, owner);
1493 		WRITE_ONCE(p->svms.faulting_task, NULL);
1494 		if (r) {
1495 			pr_debug("failed %d to get svm range pages\n", r);
1496 			goto unreserve_out;
1497 		}
1498 
1499 		offset = (addr - start) >> PAGE_SHIFT;
1500 		r = svm_range_dma_map(prange, ctx.bitmap, offset, npages,
1501 				      hmm_range->hmm_pfns);
1502 		if (r) {
1503 			pr_debug("failed %d to dma map range\n", r);
1504 			goto unreserve_out;
1505 		}
1506 
1507 		svm_range_lock(prange);
1508 		if (amdgpu_hmm_range_get_pages_done(hmm_range)) {
1509 			pr_debug("hmm update the range, need validate again\n");
1510 			r = -EAGAIN;
1511 			goto unlock_out;
1512 		}
1513 		if (!list_empty(&prange->child_list)) {
1514 			pr_debug("range split by unmap in parallel, validate again\n");
1515 			r = -EAGAIN;
1516 			goto unlock_out;
1517 		}
1518 
1519 		r = svm_range_map_to_gpus(prange, offset, npages, readonly,
1520 					  ctx.bitmap, wait);
1521 
1522 unlock_out:
1523 		svm_range_unlock(prange);
1524 
1525 		addr = next;
1526 	}
1527 
1528 	if (addr == end)
1529 		prange->validated_once = true;
1530 
1531 unreserve_out:
1532 	svm_range_unreserve_bos(&ctx);
1533 
1534 	if (!r)
1535 		prange->validate_timestamp = ktime_to_us(ktime_get());
1536 
1537 	return r;
1538 }
1539 
1540 /**
1541  * svm_range_list_lock_and_flush_work - flush pending deferred work
1542  *
1543  * @svms: the svm range list
1544  * @mm: the mm structure
1545  *
1546  * Context: Returns with mmap write lock held, pending deferred work flushed
1547  *
1548  */
1549 void
1550 svm_range_list_lock_and_flush_work(struct svm_range_list *svms,
1551 				   struct mm_struct *mm)
1552 {
1553 retry_flush_work:
1554 	flush_work(&svms->deferred_list_work);
1555 	mmap_write_lock(mm);
1556 
1557 	if (list_empty(&svms->deferred_range_list))
1558 		return;
1559 	mmap_write_unlock(mm);
1560 	pr_debug("retry flush\n");
1561 	goto retry_flush_work;
1562 }
1563 
1564 static void svm_range_restore_work(struct work_struct *work)
1565 {
1566 	struct delayed_work *dwork = to_delayed_work(work);
1567 	struct amdkfd_process_info *process_info;
1568 	struct svm_range_list *svms;
1569 	struct svm_range *prange;
1570 	struct kfd_process *p;
1571 	struct mm_struct *mm;
1572 	int evicted_ranges;
1573 	int invalid;
1574 	int r;
1575 
1576 	svms = container_of(dwork, struct svm_range_list, restore_work);
1577 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1578 	if (!evicted_ranges)
1579 		return;
1580 
1581 	pr_debug("restore svm ranges\n");
1582 
1583 	/* kfd_process_notifier_release destroys this worker thread. So during
1584 	 * the lifetime of this thread, kfd_process and mm will be valid.
1585 	 */
1586 	p = container_of(svms, struct kfd_process, svms);
1587 	process_info = p->kgd_process_info;
1588 	mm = p->mm;
1589 	if (!mm)
1590 		return;
1591 
1592 	mutex_lock(&process_info->lock);
1593 	svm_range_list_lock_and_flush_work(svms, mm);
1594 	mutex_lock(&svms->lock);
1595 
1596 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1597 
1598 	list_for_each_entry(prange, &svms->list, list) {
1599 		invalid = atomic_read(&prange->invalid);
1600 		if (!invalid)
1601 			continue;
1602 
1603 		pr_debug("restoring svms 0x%p prange 0x%p [0x%lx %lx] inv %d\n",
1604 			 prange->svms, prange, prange->start, prange->last,
1605 			 invalid);
1606 
1607 		/*
1608 		 * If range is migrating, wait for migration is done.
1609 		 */
1610 		mutex_lock(&prange->migrate_mutex);
1611 
1612 		r = svm_range_validate_and_map(mm, prange, MAX_GPU_INSTANCE,
1613 					       false, true);
1614 		if (r)
1615 			pr_debug("failed %d to map 0x%lx to gpus\n", r,
1616 				 prange->start);
1617 
1618 		mutex_unlock(&prange->migrate_mutex);
1619 		if (r)
1620 			goto out_reschedule;
1621 
1622 		if (atomic_cmpxchg(&prange->invalid, invalid, 0) != invalid)
1623 			goto out_reschedule;
1624 	}
1625 
1626 	if (atomic_cmpxchg(&svms->evicted_ranges, evicted_ranges, 0) !=
1627 	    evicted_ranges)
1628 		goto out_reschedule;
1629 
1630 	evicted_ranges = 0;
1631 
1632 	r = kgd2kfd_resume_mm(mm);
1633 	if (r) {
1634 		/* No recovery from this failure. Probably the CP is
1635 		 * hanging. No point trying again.
1636 		 */
1637 		pr_debug("failed %d to resume KFD\n", r);
1638 	}
1639 
1640 	pr_debug("restore svm ranges successfully\n");
1641 
1642 out_reschedule:
1643 	mutex_unlock(&svms->lock);
1644 	mmap_write_unlock(mm);
1645 	mutex_unlock(&process_info->lock);
1646 
1647 	/* If validation failed, reschedule another attempt */
1648 	if (evicted_ranges) {
1649 		pr_debug("reschedule to restore svm range\n");
1650 		schedule_delayed_work(&svms->restore_work,
1651 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1652 	}
1653 }
1654 
1655 /**
1656  * svm_range_evict - evict svm range
1657  *
1658  * Stop all queues of the process to ensure GPU doesn't access the memory, then
1659  * return to let CPU evict the buffer and proceed CPU pagetable update.
1660  *
1661  * Don't need use lock to sync cpu pagetable invalidation with GPU execution.
1662  * If invalidation happens while restore work is running, restore work will
1663  * restart to ensure to get the latest CPU pages mapping to GPU, then start
1664  * the queues.
1665  */
1666 static int
1667 svm_range_evict(struct svm_range *prange, struct mm_struct *mm,
1668 		unsigned long start, unsigned long last)
1669 {
1670 	struct svm_range_list *svms = prange->svms;
1671 	struct svm_range *pchild;
1672 	struct kfd_process *p;
1673 	int r = 0;
1674 
1675 	p = container_of(svms, struct kfd_process, svms);
1676 
1677 	pr_debug("invalidate svms 0x%p prange [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
1678 		 svms, prange->start, prange->last, start, last);
1679 
1680 	if (!p->xnack_enabled) {
1681 		int evicted_ranges;
1682 
1683 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1684 			mutex_lock_nested(&pchild->lock, 1);
1685 			if (pchild->start <= last && pchild->last >= start) {
1686 				pr_debug("increment pchild invalid [0x%lx 0x%lx]\n",
1687 					 pchild->start, pchild->last);
1688 				atomic_inc(&pchild->invalid);
1689 			}
1690 			mutex_unlock(&pchild->lock);
1691 		}
1692 
1693 		if (prange->start <= last && prange->last >= start)
1694 			atomic_inc(&prange->invalid);
1695 
1696 		evicted_ranges = atomic_inc_return(&svms->evicted_ranges);
1697 		if (evicted_ranges != 1)
1698 			return r;
1699 
1700 		pr_debug("evicting svms 0x%p range [0x%lx 0x%lx]\n",
1701 			 prange->svms, prange->start, prange->last);
1702 
1703 		/* First eviction, stop the queues */
1704 		r = kgd2kfd_quiesce_mm(mm);
1705 		if (r)
1706 			pr_debug("failed to quiesce KFD\n");
1707 
1708 		pr_debug("schedule to restore svm %p ranges\n", svms);
1709 		schedule_delayed_work(&svms->restore_work,
1710 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1711 	} else {
1712 		unsigned long s, l;
1713 
1714 		pr_debug("invalidate unmap svms 0x%p [0x%lx 0x%lx] from GPUs\n",
1715 			 prange->svms, start, last);
1716 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1717 			mutex_lock_nested(&pchild->lock, 1);
1718 			s = max(start, pchild->start);
1719 			l = min(last, pchild->last);
1720 			if (l >= s)
1721 				svm_range_unmap_from_gpus(pchild, s, l);
1722 			mutex_unlock(&pchild->lock);
1723 		}
1724 		s = max(start, prange->start);
1725 		l = min(last, prange->last);
1726 		if (l >= s)
1727 			svm_range_unmap_from_gpus(prange, s, l);
1728 	}
1729 
1730 	return r;
1731 }
1732 
1733 static struct svm_range *svm_range_clone(struct svm_range *old)
1734 {
1735 	struct svm_range *new;
1736 
1737 	new = svm_range_new(old->svms, old->start, old->last);
1738 	if (!new)
1739 		return NULL;
1740 
1741 	if (old->svm_bo) {
1742 		new->ttm_res = old->ttm_res;
1743 		new->offset = old->offset;
1744 		new->svm_bo = svm_range_bo_ref(old->svm_bo);
1745 		spin_lock(&new->svm_bo->list_lock);
1746 		list_add(&new->svm_bo_list, &new->svm_bo->range_list);
1747 		spin_unlock(&new->svm_bo->list_lock);
1748 	}
1749 	new->flags = old->flags;
1750 	new->preferred_loc = old->preferred_loc;
1751 	new->prefetch_loc = old->prefetch_loc;
1752 	new->actual_loc = old->actual_loc;
1753 	new->granularity = old->granularity;
1754 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
1755 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
1756 
1757 	return new;
1758 }
1759 
1760 /**
1761  * svm_range_handle_overlap - split overlap ranges
1762  * @svms: svm range list header
1763  * @new: range added with this attributes
1764  * @start: range added start address, in pages
1765  * @last: range last address, in pages
1766  * @update_list: output, the ranges attributes are updated. For set_attr, this
1767  *               will do validation and map to GPUs. For unmap, this will be
1768  *               removed and unmap from GPUs
1769  * @insert_list: output, the ranges will be inserted into svms, attributes are
1770  *               not changes. For set_attr, this will add into svms.
1771  * @remove_list:output, the ranges will be removed from svms
1772  * @left: the remaining range after overlap, For set_attr, this will be added
1773  *        as new range.
1774  *
1775  * Total have 5 overlap cases.
1776  *
1777  * This function handles overlap of an address interval with existing
1778  * struct svm_ranges for applying new attributes. This may require
1779  * splitting existing struct svm_ranges. All changes should be applied to
1780  * the range_list and interval tree transactionally. If any split operation
1781  * fails, the entire update fails. Therefore the existing overlapping
1782  * svm_ranges are cloned and the original svm_ranges left unchanged. If the
1783  * transaction succeeds, the modified clones are added and the originals
1784  * freed. Otherwise the clones are removed and the old svm_ranges remain.
1785  *
1786  * Context: The caller must hold svms->lock
1787  */
1788 static int
1789 svm_range_handle_overlap(struct svm_range_list *svms, struct svm_range *new,
1790 			 unsigned long start, unsigned long last,
1791 			 struct list_head *update_list,
1792 			 struct list_head *insert_list,
1793 			 struct list_head *remove_list,
1794 			 unsigned long *left)
1795 {
1796 	struct interval_tree_node *node;
1797 	struct svm_range *prange;
1798 	struct svm_range *tmp;
1799 	int r = 0;
1800 
1801 	INIT_LIST_HEAD(update_list);
1802 	INIT_LIST_HEAD(insert_list);
1803 	INIT_LIST_HEAD(remove_list);
1804 
1805 	node = interval_tree_iter_first(&svms->objects, start, last);
1806 	while (node) {
1807 		struct interval_tree_node *next;
1808 		struct svm_range *old;
1809 		unsigned long next_start;
1810 
1811 		pr_debug("found overlap node [0x%lx 0x%lx]\n", node->start,
1812 			 node->last);
1813 
1814 		old = container_of(node, struct svm_range, it_node);
1815 		next = interval_tree_iter_next(node, start, last);
1816 		next_start = min(node->last, last) + 1;
1817 
1818 		if (node->start < start || node->last > last) {
1819 			/* node intersects the updated range, clone+split it */
1820 			prange = svm_range_clone(old);
1821 			if (!prange) {
1822 				r = -ENOMEM;
1823 				goto out;
1824 			}
1825 
1826 			list_add(&old->remove_list, remove_list);
1827 			list_add(&prange->insert_list, insert_list);
1828 
1829 			if (node->start < start) {
1830 				pr_debug("change old range start\n");
1831 				r = svm_range_split_head(prange, new, start,
1832 							 insert_list);
1833 				if (r)
1834 					goto out;
1835 			}
1836 			if (node->last > last) {
1837 				pr_debug("change old range last\n");
1838 				r = svm_range_split_tail(prange, new, last,
1839 							 insert_list);
1840 				if (r)
1841 					goto out;
1842 			}
1843 		} else {
1844 			/* The node is contained within start..last,
1845 			 * just update it
1846 			 */
1847 			prange = old;
1848 		}
1849 
1850 		if (!svm_range_is_same_attrs(prange, new))
1851 			list_add(&prange->update_list, update_list);
1852 
1853 		/* insert a new node if needed */
1854 		if (node->start > start) {
1855 			prange = svm_range_new(prange->svms, start,
1856 					       node->start - 1);
1857 			if (!prange) {
1858 				r = -ENOMEM;
1859 				goto out;
1860 			}
1861 
1862 			list_add(&prange->insert_list, insert_list);
1863 			list_add(&prange->update_list, update_list);
1864 		}
1865 
1866 		node = next;
1867 		start = next_start;
1868 	}
1869 
1870 	if (left && start <= last)
1871 		*left = last - start + 1;
1872 
1873 out:
1874 	if (r)
1875 		list_for_each_entry_safe(prange, tmp, insert_list, insert_list)
1876 			svm_range_free(prange);
1877 
1878 	return r;
1879 }
1880 
1881 static void
1882 svm_range_update_notifier_and_interval_tree(struct mm_struct *mm,
1883 					    struct svm_range *prange)
1884 {
1885 	unsigned long start;
1886 	unsigned long last;
1887 
1888 	start = prange->notifier.interval_tree.start >> PAGE_SHIFT;
1889 	last = prange->notifier.interval_tree.last >> PAGE_SHIFT;
1890 
1891 	if (prange->start == start && prange->last == last)
1892 		return;
1893 
1894 	pr_debug("up notifier 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
1895 		  prange->svms, prange, start, last, prange->start,
1896 		  prange->last);
1897 
1898 	if (start != 0 && last != 0) {
1899 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
1900 		svm_range_remove_notifier(prange);
1901 	}
1902 	prange->it_node.start = prange->start;
1903 	prange->it_node.last = prange->last;
1904 
1905 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
1906 	svm_range_add_notifier_locked(mm, prange);
1907 }
1908 
1909 static void
1910 svm_range_handle_list_op(struct svm_range_list *svms, struct svm_range *prange)
1911 {
1912 	struct mm_struct *mm = prange->work_item.mm;
1913 
1914 	switch (prange->work_item.op) {
1915 	case SVM_OP_NULL:
1916 		pr_debug("NULL OP 0x%p prange 0x%p [0x%lx 0x%lx]\n",
1917 			 svms, prange, prange->start, prange->last);
1918 		break;
1919 	case SVM_OP_UNMAP_RANGE:
1920 		pr_debug("remove 0x%p prange 0x%p [0x%lx 0x%lx]\n",
1921 			 svms, prange, prange->start, prange->last);
1922 		svm_range_unlink(prange);
1923 		svm_range_remove_notifier(prange);
1924 		svm_range_free(prange);
1925 		break;
1926 	case SVM_OP_UPDATE_RANGE_NOTIFIER:
1927 		pr_debug("update notifier 0x%p prange 0x%p [0x%lx 0x%lx]\n",
1928 			 svms, prange, prange->start, prange->last);
1929 		svm_range_update_notifier_and_interval_tree(mm, prange);
1930 		break;
1931 	case SVM_OP_UPDATE_RANGE_NOTIFIER_AND_MAP:
1932 		pr_debug("update and map 0x%p prange 0x%p [0x%lx 0x%lx]\n",
1933 			 svms, prange, prange->start, prange->last);
1934 		svm_range_update_notifier_and_interval_tree(mm, prange);
1935 		/* TODO: implement deferred validation and mapping */
1936 		break;
1937 	case SVM_OP_ADD_RANGE:
1938 		pr_debug("add 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms, prange,
1939 			 prange->start, prange->last);
1940 		svm_range_add_to_svms(prange);
1941 		svm_range_add_notifier_locked(mm, prange);
1942 		break;
1943 	case SVM_OP_ADD_RANGE_AND_MAP:
1944 		pr_debug("add and map 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms,
1945 			 prange, prange->start, prange->last);
1946 		svm_range_add_to_svms(prange);
1947 		svm_range_add_notifier_locked(mm, prange);
1948 		/* TODO: implement deferred validation and mapping */
1949 		break;
1950 	default:
1951 		WARN_ONCE(1, "Unknown prange 0x%p work op %d\n", prange,
1952 			 prange->work_item.op);
1953 	}
1954 }
1955 
1956 static void svm_range_drain_retry_fault(struct svm_range_list *svms)
1957 {
1958 	struct kfd_process_device *pdd;
1959 	struct kfd_process *p;
1960 	uint32_t i;
1961 
1962 	p = container_of(svms, struct kfd_process, svms);
1963 
1964 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
1965 		pdd = p->pdds[i];
1966 		if (!pdd)
1967 			continue;
1968 
1969 		pr_debug("drain retry fault gpu %d svms %p\n", i, svms);
1970 
1971 		amdgpu_ih_wait_on_checkpoint_process(pdd->dev->adev,
1972 						     &pdd->dev->adev->irq.ih1);
1973 		pr_debug("drain retry fault gpu %d svms 0x%p done\n", i, svms);
1974 	}
1975 }
1976 
1977 static void svm_range_deferred_list_work(struct work_struct *work)
1978 {
1979 	struct svm_range_list *svms;
1980 	struct svm_range *prange;
1981 	struct mm_struct *mm;
1982 
1983 	svms = container_of(work, struct svm_range_list, deferred_list_work);
1984 	pr_debug("enter svms 0x%p\n", svms);
1985 
1986 	spin_lock(&svms->deferred_list_lock);
1987 	while (!list_empty(&svms->deferred_range_list)) {
1988 		prange = list_first_entry(&svms->deferred_range_list,
1989 					  struct svm_range, deferred_list);
1990 		spin_unlock(&svms->deferred_list_lock);
1991 		pr_debug("prange 0x%p [0x%lx 0x%lx] op %d\n", prange,
1992 			 prange->start, prange->last, prange->work_item.op);
1993 
1994 		mm = prange->work_item.mm;
1995 retry:
1996 		mmap_write_lock(mm);
1997 		mutex_lock(&svms->lock);
1998 
1999 		/* Checking for the need to drain retry faults must be in
2000 		 * mmap write lock to serialize with munmap notifiers.
2001 		 *
2002 		 * Remove from deferred_list must be inside mmap write lock,
2003 		 * otherwise, svm_range_list_lock_and_flush_work may hold mmap
2004 		 * write lock, and continue because deferred_list is empty, then
2005 		 * deferred_list handle is blocked by mmap write lock.
2006 		 */
2007 		spin_lock(&svms->deferred_list_lock);
2008 		if (unlikely(svms->drain_pagefaults)) {
2009 			svms->drain_pagefaults = false;
2010 			spin_unlock(&svms->deferred_list_lock);
2011 			mutex_unlock(&svms->lock);
2012 			mmap_write_unlock(mm);
2013 			svm_range_drain_retry_fault(svms);
2014 			goto retry;
2015 		}
2016 		list_del_init(&prange->deferred_list);
2017 		spin_unlock(&svms->deferred_list_lock);
2018 
2019 		mutex_lock(&prange->migrate_mutex);
2020 		while (!list_empty(&prange->child_list)) {
2021 			struct svm_range *pchild;
2022 
2023 			pchild = list_first_entry(&prange->child_list,
2024 						struct svm_range, child_list);
2025 			pr_debug("child prange 0x%p op %d\n", pchild,
2026 				 pchild->work_item.op);
2027 			list_del_init(&pchild->child_list);
2028 			svm_range_handle_list_op(svms, pchild);
2029 		}
2030 		mutex_unlock(&prange->migrate_mutex);
2031 
2032 		svm_range_handle_list_op(svms, prange);
2033 		mutex_unlock(&svms->lock);
2034 		mmap_write_unlock(mm);
2035 
2036 		spin_lock(&svms->deferred_list_lock);
2037 	}
2038 	spin_unlock(&svms->deferred_list_lock);
2039 
2040 	pr_debug("exit svms 0x%p\n", svms);
2041 }
2042 
2043 void
2044 svm_range_add_list_work(struct svm_range_list *svms, struct svm_range *prange,
2045 			struct mm_struct *mm, enum svm_work_list_ops op)
2046 {
2047 	spin_lock(&svms->deferred_list_lock);
2048 	/* Make sure pending page faults are drained in the deferred worker
2049 	 * before the range is freed to avoid straggler interrupts on
2050 	 * unmapped memory causing "phantom faults".
2051 	 */
2052 	if (op == SVM_OP_UNMAP_RANGE)
2053 		svms->drain_pagefaults = true;
2054 	/* if prange is on the deferred list */
2055 	if (!list_empty(&prange->deferred_list)) {
2056 		pr_debug("update exist prange 0x%p work op %d\n", prange, op);
2057 		WARN_ONCE(prange->work_item.mm != mm, "unmatch mm\n");
2058 		if (op != SVM_OP_NULL &&
2059 		    prange->work_item.op != SVM_OP_UNMAP_RANGE)
2060 			prange->work_item.op = op;
2061 	} else {
2062 		prange->work_item.op = op;
2063 		prange->work_item.mm = mm;
2064 		list_add_tail(&prange->deferred_list,
2065 			      &prange->svms->deferred_range_list);
2066 		pr_debug("add prange 0x%p [0x%lx 0x%lx] to work list op %d\n",
2067 			 prange, prange->start, prange->last, op);
2068 	}
2069 	spin_unlock(&svms->deferred_list_lock);
2070 }
2071 
2072 void schedule_deferred_list_work(struct svm_range_list *svms)
2073 {
2074 	spin_lock(&svms->deferred_list_lock);
2075 	if (!list_empty(&svms->deferred_range_list))
2076 		schedule_work(&svms->deferred_list_work);
2077 	spin_unlock(&svms->deferred_list_lock);
2078 }
2079 
2080 static void
2081 svm_range_unmap_split(struct mm_struct *mm, struct svm_range *parent,
2082 		      struct svm_range *prange, unsigned long start,
2083 		      unsigned long last)
2084 {
2085 	struct svm_range *head;
2086 	struct svm_range *tail;
2087 
2088 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2089 		pr_debug("prange 0x%p [0x%lx 0x%lx] is already freed\n", prange,
2090 			 prange->start, prange->last);
2091 		return;
2092 	}
2093 	if (start > prange->last || last < prange->start)
2094 		return;
2095 
2096 	head = tail = prange;
2097 	if (start > prange->start)
2098 		svm_range_split(prange, prange->start, start - 1, &tail);
2099 	if (last < tail->last)
2100 		svm_range_split(tail, last + 1, tail->last, &head);
2101 
2102 	if (head != prange && tail != prange) {
2103 		svm_range_add_child(parent, mm, head, SVM_OP_UNMAP_RANGE);
2104 		svm_range_add_child(parent, mm, tail, SVM_OP_ADD_RANGE);
2105 	} else if (tail != prange) {
2106 		svm_range_add_child(parent, mm, tail, SVM_OP_UNMAP_RANGE);
2107 	} else if (head != prange) {
2108 		svm_range_add_child(parent, mm, head, SVM_OP_UNMAP_RANGE);
2109 	} else if (parent != prange) {
2110 		prange->work_item.op = SVM_OP_UNMAP_RANGE;
2111 	}
2112 }
2113 
2114 static void
2115 svm_range_unmap_from_cpu(struct mm_struct *mm, struct svm_range *prange,
2116 			 unsigned long start, unsigned long last)
2117 {
2118 	struct svm_range_list *svms;
2119 	struct svm_range *pchild;
2120 	struct kfd_process *p;
2121 	unsigned long s, l;
2122 	bool unmap_parent;
2123 
2124 	p = kfd_lookup_process_by_mm(mm);
2125 	if (!p)
2126 		return;
2127 	svms = &p->svms;
2128 
2129 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n", svms,
2130 		 prange, prange->start, prange->last, start, last);
2131 
2132 	unmap_parent = start <= prange->start && last >= prange->last;
2133 
2134 	list_for_each_entry(pchild, &prange->child_list, child_list) {
2135 		mutex_lock_nested(&pchild->lock, 1);
2136 		s = max(start, pchild->start);
2137 		l = min(last, pchild->last);
2138 		if (l >= s)
2139 			svm_range_unmap_from_gpus(pchild, s, l);
2140 		svm_range_unmap_split(mm, prange, pchild, start, last);
2141 		mutex_unlock(&pchild->lock);
2142 	}
2143 	s = max(start, prange->start);
2144 	l = min(last, prange->last);
2145 	if (l >= s)
2146 		svm_range_unmap_from_gpus(prange, s, l);
2147 	svm_range_unmap_split(mm, prange, prange, start, last);
2148 
2149 	if (unmap_parent)
2150 		svm_range_add_list_work(svms, prange, mm, SVM_OP_UNMAP_RANGE);
2151 	else
2152 		svm_range_add_list_work(svms, prange, mm,
2153 					SVM_OP_UPDATE_RANGE_NOTIFIER);
2154 	schedule_deferred_list_work(svms);
2155 
2156 	kfd_unref_process(p);
2157 }
2158 
2159 /**
2160  * svm_range_cpu_invalidate_pagetables - interval notifier callback
2161  *
2162  * If event is MMU_NOTIFY_UNMAP, this is from CPU unmap range, otherwise, it
2163  * is from migration, or CPU page invalidation callback.
2164  *
2165  * For unmap event, unmap range from GPUs, remove prange from svms in a delayed
2166  * work thread, and split prange if only part of prange is unmapped.
2167  *
2168  * For invalidation event, if GPU retry fault is not enabled, evict the queues,
2169  * then schedule svm_range_restore_work to update GPU mapping and resume queues.
2170  * If GPU retry fault is enabled, unmap the svm range from GPU, retry fault will
2171  * update GPU mapping to recover.
2172  *
2173  * Context: mmap lock, notifier_invalidate_start lock are held
2174  *          for invalidate event, prange lock is held if this is from migration
2175  */
2176 static bool
2177 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
2178 				    const struct mmu_notifier_range *range,
2179 				    unsigned long cur_seq)
2180 {
2181 	struct svm_range *prange;
2182 	unsigned long start;
2183 	unsigned long last;
2184 
2185 	if (range->event == MMU_NOTIFY_RELEASE)
2186 		return true;
2187 
2188 	start = mni->interval_tree.start;
2189 	last = mni->interval_tree.last;
2190 	start = (start > range->start ? start : range->start) >> PAGE_SHIFT;
2191 	last = (last < (range->end - 1) ? last : range->end - 1) >> PAGE_SHIFT;
2192 	pr_debug("[0x%lx 0x%lx] range[0x%lx 0x%lx] notifier[0x%lx 0x%lx] %d\n",
2193 		 start, last, range->start >> PAGE_SHIFT,
2194 		 (range->end - 1) >> PAGE_SHIFT,
2195 		 mni->interval_tree.start >> PAGE_SHIFT,
2196 		 mni->interval_tree.last >> PAGE_SHIFT, range->event);
2197 
2198 	prange = container_of(mni, struct svm_range, notifier);
2199 
2200 	svm_range_lock(prange);
2201 	mmu_interval_set_seq(mni, cur_seq);
2202 
2203 	switch (range->event) {
2204 	case MMU_NOTIFY_UNMAP:
2205 		svm_range_unmap_from_cpu(mni->mm, prange, start, last);
2206 		break;
2207 	default:
2208 		svm_range_evict(prange, mni->mm, start, last);
2209 		break;
2210 	}
2211 
2212 	svm_range_unlock(prange);
2213 
2214 	return true;
2215 }
2216 
2217 /**
2218  * svm_range_from_addr - find svm range from fault address
2219  * @svms: svm range list header
2220  * @addr: address to search range interval tree, in pages
2221  * @parent: parent range if range is on child list
2222  *
2223  * Context: The caller must hold svms->lock
2224  *
2225  * Return: the svm_range found or NULL
2226  */
2227 struct svm_range *
2228 svm_range_from_addr(struct svm_range_list *svms, unsigned long addr,
2229 		    struct svm_range **parent)
2230 {
2231 	struct interval_tree_node *node;
2232 	struct svm_range *prange;
2233 	struct svm_range *pchild;
2234 
2235 	node = interval_tree_iter_first(&svms->objects, addr, addr);
2236 	if (!node)
2237 		return NULL;
2238 
2239 	prange = container_of(node, struct svm_range, it_node);
2240 	pr_debug("address 0x%lx prange [0x%lx 0x%lx] node [0x%lx 0x%lx]\n",
2241 		 addr, prange->start, prange->last, node->start, node->last);
2242 
2243 	if (addr >= prange->start && addr <= prange->last) {
2244 		if (parent)
2245 			*parent = prange;
2246 		return prange;
2247 	}
2248 	list_for_each_entry(pchild, &prange->child_list, child_list)
2249 		if (addr >= pchild->start && addr <= pchild->last) {
2250 			pr_debug("found address 0x%lx pchild [0x%lx 0x%lx]\n",
2251 				 addr, pchild->start, pchild->last);
2252 			if (parent)
2253 				*parent = prange;
2254 			return pchild;
2255 		}
2256 
2257 	return NULL;
2258 }
2259 
2260 /* svm_range_best_restore_location - decide the best fault restore location
2261  * @prange: svm range structure
2262  * @adev: the GPU on which vm fault happened
2263  *
2264  * This is only called when xnack is on, to decide the best location to restore
2265  * the range mapping after GPU vm fault. Caller uses the best location to do
2266  * migration if actual loc is not best location, then update GPU page table
2267  * mapping to the best location.
2268  *
2269  * If the preferred loc is accessible by faulting GPU, use preferred loc.
2270  * If vm fault gpu idx is on range ACCESSIBLE bitmap, best_loc is vm fault gpu
2271  * If vm fault gpu idx is on range ACCESSIBLE_IN_PLACE bitmap, then
2272  *    if range actual loc is cpu, best_loc is cpu
2273  *    if vm fault gpu is on xgmi same hive of range actual loc gpu, best_loc is
2274  *    range actual loc.
2275  * Otherwise, GPU no access, best_loc is -1.
2276  *
2277  * Return:
2278  * -1 means vm fault GPU no access
2279  * 0 for CPU or GPU id
2280  */
2281 static int32_t
2282 svm_range_best_restore_location(struct svm_range *prange,
2283 				struct amdgpu_device *adev,
2284 				int32_t *gpuidx)
2285 {
2286 	struct amdgpu_device *bo_adev, *preferred_adev;
2287 	struct kfd_process *p;
2288 	uint32_t gpuid;
2289 	int r;
2290 
2291 	p = container_of(prange->svms, struct kfd_process, svms);
2292 
2293 	r = kfd_process_gpuid_from_adev(p, adev, &gpuid, gpuidx);
2294 	if (r < 0) {
2295 		pr_debug("failed to get gpuid from kgd\n");
2296 		return -1;
2297 	}
2298 
2299 	if (prange->preferred_loc == gpuid ||
2300 	    prange->preferred_loc == KFD_IOCTL_SVM_LOCATION_SYSMEM) {
2301 		return prange->preferred_loc;
2302 	} else if (prange->preferred_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
2303 		preferred_adev = svm_range_get_adev_by_id(prange,
2304 							prange->preferred_loc);
2305 		if (amdgpu_xgmi_same_hive(adev, preferred_adev))
2306 			return prange->preferred_loc;
2307 		/* fall through */
2308 	}
2309 
2310 	if (test_bit(*gpuidx, prange->bitmap_access))
2311 		return gpuid;
2312 
2313 	if (test_bit(*gpuidx, prange->bitmap_aip)) {
2314 		if (!prange->actual_loc)
2315 			return 0;
2316 
2317 		bo_adev = svm_range_get_adev_by_id(prange, prange->actual_loc);
2318 		if (amdgpu_xgmi_same_hive(adev, bo_adev))
2319 			return prange->actual_loc;
2320 		else
2321 			return 0;
2322 	}
2323 
2324 	return -1;
2325 }
2326 
2327 static int
2328 svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
2329 			       unsigned long *start, unsigned long *last,
2330 			       bool *is_heap_stack)
2331 {
2332 	struct vm_area_struct *vma;
2333 	struct interval_tree_node *node;
2334 	unsigned long start_limit, end_limit;
2335 
2336 	vma = find_vma(p->mm, addr << PAGE_SHIFT);
2337 	if (!vma || (addr << PAGE_SHIFT) < vma->vm_start) {
2338 		pr_debug("VMA does not exist in address [0x%llx]\n", addr);
2339 		return -EFAULT;
2340 	}
2341 
2342 	*is_heap_stack = (vma->vm_start <= vma->vm_mm->brk &&
2343 			  vma->vm_end >= vma->vm_mm->start_brk) ||
2344 			 (vma->vm_start <= vma->vm_mm->start_stack &&
2345 			  vma->vm_end >= vma->vm_mm->start_stack);
2346 
2347 	start_limit = max(vma->vm_start >> PAGE_SHIFT,
2348 		      (unsigned long)ALIGN_DOWN(addr, 2UL << 8));
2349 	end_limit = min(vma->vm_end >> PAGE_SHIFT,
2350 		    (unsigned long)ALIGN(addr + 1, 2UL << 8));
2351 	/* First range that starts after the fault address */
2352 	node = interval_tree_iter_first(&p->svms.objects, addr + 1, ULONG_MAX);
2353 	if (node) {
2354 		end_limit = min(end_limit, node->start);
2355 		/* Last range that ends before the fault address */
2356 		node = container_of(rb_prev(&node->rb),
2357 				    struct interval_tree_node, rb);
2358 	} else {
2359 		/* Last range must end before addr because
2360 		 * there was no range after addr
2361 		 */
2362 		node = container_of(rb_last(&p->svms.objects.rb_root),
2363 				    struct interval_tree_node, rb);
2364 	}
2365 	if (node) {
2366 		if (node->last >= addr) {
2367 			WARN(1, "Overlap with prev node and page fault addr\n");
2368 			return -EFAULT;
2369 		}
2370 		start_limit = max(start_limit, node->last + 1);
2371 	}
2372 
2373 	*start = start_limit;
2374 	*last = end_limit - 1;
2375 
2376 	pr_debug("vma [0x%lx 0x%lx] range [0x%lx 0x%lx] is_heap_stack %d\n",
2377 		 vma->vm_start >> PAGE_SHIFT, vma->vm_end >> PAGE_SHIFT,
2378 		 *start, *last, *is_heap_stack);
2379 
2380 	return 0;
2381 }
2382 
2383 static int
2384 svm_range_check_vm_userptr(struct kfd_process *p, uint64_t start, uint64_t last,
2385 			   uint64_t *bo_s, uint64_t *bo_l)
2386 {
2387 	struct amdgpu_bo_va_mapping *mapping;
2388 	struct interval_tree_node *node;
2389 	struct amdgpu_bo *bo = NULL;
2390 	unsigned long userptr;
2391 	uint32_t i;
2392 	int r;
2393 
2394 	for (i = 0; i < p->n_pdds; i++) {
2395 		struct amdgpu_vm *vm;
2396 
2397 		if (!p->pdds[i]->drm_priv)
2398 			continue;
2399 
2400 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
2401 		r = amdgpu_bo_reserve(vm->root.bo, false);
2402 		if (r)
2403 			return r;
2404 
2405 		/* Check userptr by searching entire vm->va interval tree */
2406 		node = interval_tree_iter_first(&vm->va, 0, ~0ULL);
2407 		while (node) {
2408 			mapping = container_of((struct rb_node *)node,
2409 					       struct amdgpu_bo_va_mapping, rb);
2410 			bo = mapping->bo_va->base.bo;
2411 
2412 			if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm,
2413 							 start << PAGE_SHIFT,
2414 							 last << PAGE_SHIFT,
2415 							 &userptr)) {
2416 				node = interval_tree_iter_next(node, 0, ~0ULL);
2417 				continue;
2418 			}
2419 
2420 			pr_debug("[0x%llx 0x%llx] already userptr mapped\n",
2421 				 start, last);
2422 			if (bo_s && bo_l) {
2423 				*bo_s = userptr >> PAGE_SHIFT;
2424 				*bo_l = *bo_s + bo->tbo.ttm->num_pages - 1;
2425 			}
2426 			amdgpu_bo_unreserve(vm->root.bo);
2427 			return -EADDRINUSE;
2428 		}
2429 		amdgpu_bo_unreserve(vm->root.bo);
2430 	}
2431 	return 0;
2432 }
2433 
2434 static struct
2435 svm_range *svm_range_create_unregistered_range(struct amdgpu_device *adev,
2436 						struct kfd_process *p,
2437 						struct mm_struct *mm,
2438 						int64_t addr)
2439 {
2440 	struct svm_range *prange = NULL;
2441 	unsigned long start, last;
2442 	uint32_t gpuid, gpuidx;
2443 	bool is_heap_stack;
2444 	uint64_t bo_s = 0;
2445 	uint64_t bo_l = 0;
2446 	int r;
2447 
2448 	if (svm_range_get_range_boundaries(p, addr, &start, &last,
2449 					   &is_heap_stack))
2450 		return NULL;
2451 
2452 	r = svm_range_check_vm(p, start, last, &bo_s, &bo_l);
2453 	if (r != -EADDRINUSE)
2454 		r = svm_range_check_vm_userptr(p, start, last, &bo_s, &bo_l);
2455 
2456 	if (r == -EADDRINUSE) {
2457 		if (addr >= bo_s && addr <= bo_l)
2458 			return NULL;
2459 
2460 		/* Create one page svm range if 2MB range overlapping */
2461 		start = addr;
2462 		last = addr;
2463 	}
2464 
2465 	prange = svm_range_new(&p->svms, start, last);
2466 	if (!prange) {
2467 		pr_debug("Failed to create prange in address [0x%llx]\n", addr);
2468 		return NULL;
2469 	}
2470 	if (kfd_process_gpuid_from_adev(p, adev, &gpuid, &gpuidx)) {
2471 		pr_debug("failed to get gpuid from kgd\n");
2472 		svm_range_free(prange);
2473 		return NULL;
2474 	}
2475 
2476 	if (is_heap_stack)
2477 		prange->preferred_loc = KFD_IOCTL_SVM_LOCATION_SYSMEM;
2478 
2479 	svm_range_add_to_svms(prange);
2480 	svm_range_add_notifier_locked(mm, prange);
2481 
2482 	return prange;
2483 }
2484 
2485 /* svm_range_skip_recover - decide if prange can be recovered
2486  * @prange: svm range structure
2487  *
2488  * GPU vm retry fault handle skip recover the range for cases:
2489  * 1. prange is on deferred list to be removed after unmap, it is stale fault,
2490  *    deferred list work will drain the stale fault before free the prange.
2491  * 2. prange is on deferred list to add interval notifier after split, or
2492  * 3. prange is child range, it is split from parent prange, recover later
2493  *    after interval notifier is added.
2494  *
2495  * Return: true to skip recover, false to recover
2496  */
2497 static bool svm_range_skip_recover(struct svm_range *prange)
2498 {
2499 	struct svm_range_list *svms = prange->svms;
2500 
2501 	spin_lock(&svms->deferred_list_lock);
2502 	if (list_empty(&prange->deferred_list) &&
2503 	    list_empty(&prange->child_list)) {
2504 		spin_unlock(&svms->deferred_list_lock);
2505 		return false;
2506 	}
2507 	spin_unlock(&svms->deferred_list_lock);
2508 
2509 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2510 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] unmapped\n",
2511 			 svms, prange, prange->start, prange->last);
2512 		return true;
2513 	}
2514 	if (prange->work_item.op == SVM_OP_ADD_RANGE_AND_MAP ||
2515 	    prange->work_item.op == SVM_OP_ADD_RANGE) {
2516 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] not added yet\n",
2517 			 svms, prange, prange->start, prange->last);
2518 		return true;
2519 	}
2520 	return false;
2521 }
2522 
2523 static void
2524 svm_range_count_fault(struct amdgpu_device *adev, struct kfd_process *p,
2525 		      int32_t gpuidx)
2526 {
2527 	struct kfd_process_device *pdd;
2528 
2529 	/* fault is on different page of same range
2530 	 * or fault is skipped to recover later
2531 	 * or fault is on invalid virtual address
2532 	 */
2533 	if (gpuidx == MAX_GPU_INSTANCE) {
2534 		uint32_t gpuid;
2535 		int r;
2536 
2537 		r = kfd_process_gpuid_from_adev(p, adev, &gpuid, &gpuidx);
2538 		if (r < 0)
2539 			return;
2540 	}
2541 
2542 	/* fault is recovered
2543 	 * or fault cannot recover because GPU no access on the range
2544 	 */
2545 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
2546 	if (pdd)
2547 		WRITE_ONCE(pdd->faults, pdd->faults + 1);
2548 }
2549 
2550 static bool
2551 svm_fault_allowed(struct mm_struct *mm, uint64_t addr, bool write_fault)
2552 {
2553 	unsigned long requested = VM_READ;
2554 	struct vm_area_struct *vma;
2555 
2556 	if (write_fault)
2557 		requested |= VM_WRITE;
2558 
2559 	vma = find_vma(mm, addr << PAGE_SHIFT);
2560 	if (!vma || (addr << PAGE_SHIFT) < vma->vm_start) {
2561 		pr_debug("address 0x%llx VMA is removed\n", addr);
2562 		return true;
2563 	}
2564 
2565 	pr_debug("requested 0x%lx, vma permission flags 0x%lx\n", requested,
2566 		vma->vm_flags);
2567 	return (vma->vm_flags & requested) == requested;
2568 }
2569 
2570 int
2571 svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
2572 			uint64_t addr, bool write_fault)
2573 {
2574 	struct mm_struct *mm = NULL;
2575 	struct svm_range_list *svms;
2576 	struct svm_range *prange;
2577 	struct kfd_process *p;
2578 	uint64_t timestamp;
2579 	int32_t best_loc;
2580 	int32_t gpuidx = MAX_GPU_INSTANCE;
2581 	bool write_locked = false;
2582 	int r = 0;
2583 
2584 	if (!KFD_IS_SVM_API_SUPPORTED(adev->kfd.dev)) {
2585 		pr_debug("device does not support SVM\n");
2586 		return -EFAULT;
2587 	}
2588 
2589 	p = kfd_lookup_process_by_pasid(pasid);
2590 	if (!p) {
2591 		pr_debug("kfd process not founded pasid 0x%x\n", pasid);
2592 		return -ESRCH;
2593 	}
2594 	if (!p->xnack_enabled) {
2595 		pr_debug("XNACK not enabled for pasid 0x%x\n", pasid);
2596 		r = -EFAULT;
2597 		goto out;
2598 	}
2599 	svms = &p->svms;
2600 
2601 	pr_debug("restoring svms 0x%p fault address 0x%llx\n", svms, addr);
2602 
2603 	mm = get_task_mm(p->lead_thread);
2604 	if (!mm) {
2605 		pr_debug("svms 0x%p failed to get mm\n", svms);
2606 		r = -ESRCH;
2607 		goto out;
2608 	}
2609 
2610 	mmap_read_lock(mm);
2611 retry_write_locked:
2612 	mutex_lock(&svms->lock);
2613 	prange = svm_range_from_addr(svms, addr, NULL);
2614 	if (!prange) {
2615 		pr_debug("failed to find prange svms 0x%p address [0x%llx]\n",
2616 			 svms, addr);
2617 		if (!write_locked) {
2618 			/* Need the write lock to create new range with MMU notifier.
2619 			 * Also flush pending deferred work to make sure the interval
2620 			 * tree is up to date before we add a new range
2621 			 */
2622 			mutex_unlock(&svms->lock);
2623 			mmap_read_unlock(mm);
2624 			mmap_write_lock(mm);
2625 			write_locked = true;
2626 			goto retry_write_locked;
2627 		}
2628 		prange = svm_range_create_unregistered_range(adev, p, mm, addr);
2629 		if (!prange) {
2630 			pr_debug("failed to create unregistered range svms 0x%p address [0x%llx]\n",
2631 				 svms, addr);
2632 			mmap_write_downgrade(mm);
2633 			r = -EFAULT;
2634 			goto out_unlock_svms;
2635 		}
2636 	}
2637 	if (write_locked)
2638 		mmap_write_downgrade(mm);
2639 
2640 	mutex_lock(&prange->migrate_mutex);
2641 
2642 	if (svm_range_skip_recover(prange)) {
2643 		amdgpu_gmc_filter_faults_remove(adev, addr, pasid);
2644 		goto out_unlock_range;
2645 	}
2646 
2647 	timestamp = ktime_to_us(ktime_get()) - prange->validate_timestamp;
2648 	/* skip duplicate vm fault on different pages of same range */
2649 	if (timestamp < AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING) {
2650 		pr_debug("svms 0x%p [0x%lx %lx] already restored\n",
2651 			 svms, prange->start, prange->last);
2652 		goto out_unlock_range;
2653 	}
2654 
2655 	if (!svm_fault_allowed(mm, addr, write_fault)) {
2656 		pr_debug("fault addr 0x%llx no %s permission\n", addr,
2657 			write_fault ? "write" : "read");
2658 		r = -EPERM;
2659 		goto out_unlock_range;
2660 	}
2661 
2662 	best_loc = svm_range_best_restore_location(prange, adev, &gpuidx);
2663 	if (best_loc == -1) {
2664 		pr_debug("svms %p failed get best restore loc [0x%lx 0x%lx]\n",
2665 			 svms, prange->start, prange->last);
2666 		r = -EACCES;
2667 		goto out_unlock_range;
2668 	}
2669 
2670 	pr_debug("svms %p [0x%lx 0x%lx] best restore 0x%x, actual loc 0x%x\n",
2671 		 svms, prange->start, prange->last, best_loc,
2672 		 prange->actual_loc);
2673 
2674 	if (prange->actual_loc != best_loc) {
2675 		if (best_loc) {
2676 			r = svm_migrate_to_vram(prange, best_loc, mm);
2677 			if (r) {
2678 				pr_debug("svm_migrate_to_vram failed (%d) at %llx, falling back to system memory\n",
2679 					 r, addr);
2680 				/* Fallback to system memory if migration to
2681 				 * VRAM failed
2682 				 */
2683 				if (prange->actual_loc)
2684 					r = svm_migrate_vram_to_ram(prange, mm);
2685 				else
2686 					r = 0;
2687 			}
2688 		} else {
2689 			r = svm_migrate_vram_to_ram(prange, mm);
2690 		}
2691 		if (r) {
2692 			pr_debug("failed %d to migrate svms %p [0x%lx 0x%lx]\n",
2693 				 r, svms, prange->start, prange->last);
2694 			goto out_unlock_range;
2695 		}
2696 	}
2697 
2698 	r = svm_range_validate_and_map(mm, prange, gpuidx, false, false);
2699 	if (r)
2700 		pr_debug("failed %d to map svms 0x%p [0x%lx 0x%lx] to gpus\n",
2701 			 r, svms, prange->start, prange->last);
2702 
2703 out_unlock_range:
2704 	mutex_unlock(&prange->migrate_mutex);
2705 out_unlock_svms:
2706 	mutex_unlock(&svms->lock);
2707 	mmap_read_unlock(mm);
2708 
2709 	svm_range_count_fault(adev, p, gpuidx);
2710 
2711 	mmput(mm);
2712 out:
2713 	kfd_unref_process(p);
2714 
2715 	if (r == -EAGAIN) {
2716 		pr_debug("recover vm fault later\n");
2717 		amdgpu_gmc_filter_faults_remove(adev, addr, pasid);
2718 		r = 0;
2719 	}
2720 	return r;
2721 }
2722 
2723 void svm_range_list_fini(struct kfd_process *p)
2724 {
2725 	struct svm_range *prange;
2726 	struct svm_range *next;
2727 
2728 	pr_debug("pasid 0x%x svms 0x%p\n", p->pasid, &p->svms);
2729 
2730 	/* Ensure list work is finished before process is destroyed */
2731 	flush_work(&p->svms.deferred_list_work);
2732 
2733 	list_for_each_entry_safe(prange, next, &p->svms.list, list) {
2734 		svm_range_unlink(prange);
2735 		svm_range_remove_notifier(prange);
2736 		svm_range_free(prange);
2737 	}
2738 
2739 	mutex_destroy(&p->svms.lock);
2740 
2741 	pr_debug("pasid 0x%x svms 0x%p done\n", p->pasid, &p->svms);
2742 }
2743 
2744 int svm_range_list_init(struct kfd_process *p)
2745 {
2746 	struct svm_range_list *svms = &p->svms;
2747 	int i;
2748 
2749 	svms->objects = RB_ROOT_CACHED;
2750 	mutex_init(&svms->lock);
2751 	INIT_LIST_HEAD(&svms->list);
2752 	atomic_set(&svms->evicted_ranges, 0);
2753 	INIT_DELAYED_WORK(&svms->restore_work, svm_range_restore_work);
2754 	INIT_WORK(&svms->deferred_list_work, svm_range_deferred_list_work);
2755 	INIT_LIST_HEAD(&svms->deferred_range_list);
2756 	spin_lock_init(&svms->deferred_list_lock);
2757 
2758 	for (i = 0; i < p->n_pdds; i++)
2759 		if (KFD_IS_SVM_API_SUPPORTED(p->pdds[i]->dev))
2760 			bitmap_set(svms->bitmap_supported, i, 1);
2761 
2762 	return 0;
2763 }
2764 
2765 /**
2766  * svm_range_check_vm - check if virtual address range mapped already
2767  * @p: current kfd_process
2768  * @start: range start address, in pages
2769  * @last: range last address, in pages
2770  * @bo_s: mapping start address in pages if address range already mapped
2771  * @bo_l: mapping last address in pages if address range already mapped
2772  *
2773  * The purpose is to avoid virtual address ranges already allocated by
2774  * kfd_ioctl_alloc_memory_of_gpu ioctl.
2775  * It looks for each pdd in the kfd_process.
2776  *
2777  * Context: Process context
2778  *
2779  * Return 0 - OK, if the range is not mapped.
2780  * Otherwise error code:
2781  * -EADDRINUSE - if address is mapped already by kfd_ioctl_alloc_memory_of_gpu
2782  * -ERESTARTSYS - A wait for the buffer to become unreserved was interrupted by
2783  * a signal. Release all buffer reservations and return to user-space.
2784  */
2785 static int
2786 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
2787 		   uint64_t *bo_s, uint64_t *bo_l)
2788 {
2789 	struct amdgpu_bo_va_mapping *mapping;
2790 	struct interval_tree_node *node;
2791 	uint32_t i;
2792 	int r;
2793 
2794 	for (i = 0; i < p->n_pdds; i++) {
2795 		struct amdgpu_vm *vm;
2796 
2797 		if (!p->pdds[i]->drm_priv)
2798 			continue;
2799 
2800 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
2801 		r = amdgpu_bo_reserve(vm->root.bo, false);
2802 		if (r)
2803 			return r;
2804 
2805 		node = interval_tree_iter_first(&vm->va, start, last);
2806 		if (node) {
2807 			pr_debug("range [0x%llx 0x%llx] already TTM mapped\n",
2808 				 start, last);
2809 			mapping = container_of((struct rb_node *)node,
2810 					       struct amdgpu_bo_va_mapping, rb);
2811 			if (bo_s && bo_l) {
2812 				*bo_s = mapping->start;
2813 				*bo_l = mapping->last;
2814 			}
2815 			amdgpu_bo_unreserve(vm->root.bo);
2816 			return -EADDRINUSE;
2817 		}
2818 		amdgpu_bo_unreserve(vm->root.bo);
2819 	}
2820 
2821 	return 0;
2822 }
2823 
2824 /**
2825  * svm_range_is_valid - check if virtual address range is valid
2826  * @p: current kfd_process
2827  * @start: range start address, in pages
2828  * @size: range size, in pages
2829  *
2830  * Valid virtual address range means it belongs to one or more VMAs
2831  *
2832  * Context: Process context
2833  *
2834  * Return:
2835  *  0 - OK, otherwise error code
2836  */
2837 static int
2838 svm_range_is_valid(struct kfd_process *p, uint64_t start, uint64_t size)
2839 {
2840 	const unsigned long device_vma = VM_IO | VM_PFNMAP | VM_MIXEDMAP;
2841 	struct vm_area_struct *vma;
2842 	unsigned long end;
2843 	unsigned long start_unchg = start;
2844 
2845 	start <<= PAGE_SHIFT;
2846 	end = start + (size << PAGE_SHIFT);
2847 	do {
2848 		vma = find_vma(p->mm, start);
2849 		if (!vma || start < vma->vm_start ||
2850 		    (vma->vm_flags & device_vma))
2851 			return -EFAULT;
2852 		start = min(end, vma->vm_end);
2853 	} while (start < end);
2854 
2855 	return svm_range_check_vm(p, start_unchg, (end - 1) >> PAGE_SHIFT, NULL,
2856 				  NULL);
2857 }
2858 
2859 /**
2860  * svm_range_add - add svm range and handle overlap
2861  * @p: the range add to this process svms
2862  * @start: page size aligned
2863  * @size: page size aligned
2864  * @nattr: number of attributes
2865  * @attrs: array of attributes
2866  * @update_list: output, the ranges need validate and update GPU mapping
2867  * @insert_list: output, the ranges need insert to svms
2868  * @remove_list: output, the ranges are replaced and need remove from svms
2869  *
2870  * Check if the virtual address range has overlap with the registered ranges,
2871  * split the overlapped range, copy and adjust pages address and vram nodes in
2872  * old and new ranges.
2873  *
2874  * Context: Process context, caller must hold svms->lock
2875  *
2876  * Return:
2877  * 0 - OK, otherwise error code
2878  */
2879 static int
2880 svm_range_add(struct kfd_process *p, uint64_t start, uint64_t size,
2881 	      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
2882 	      struct list_head *update_list, struct list_head *insert_list,
2883 	      struct list_head *remove_list)
2884 {
2885 	uint64_t last = start + size - 1UL;
2886 	struct svm_range_list *svms;
2887 	struct svm_range new = {0};
2888 	struct svm_range *prange;
2889 	unsigned long left = 0;
2890 	int r = 0;
2891 
2892 	pr_debug("svms 0x%p [0x%llx 0x%llx]\n", &p->svms, start, last);
2893 
2894 	svm_range_apply_attrs(p, &new, nattr, attrs);
2895 
2896 	svms = &p->svms;
2897 
2898 	r = svm_range_handle_overlap(svms, &new, start, last, update_list,
2899 				     insert_list, remove_list, &left);
2900 	if (r)
2901 		return r;
2902 
2903 	if (left) {
2904 		prange = svm_range_new(svms, last - left + 1, last);
2905 		list_add(&prange->insert_list, insert_list);
2906 		list_add(&prange->update_list, update_list);
2907 	}
2908 
2909 	return 0;
2910 }
2911 
2912 /**
2913  * svm_range_best_prefetch_location - decide the best prefetch location
2914  * @prange: svm range structure
2915  *
2916  * For xnack off:
2917  * If range map to single GPU, the best prefetch location is prefetch_loc, which
2918  * can be CPU or GPU.
2919  *
2920  * If range is ACCESS or ACCESS_IN_PLACE by mGPUs, only if mGPU connection on
2921  * XGMI same hive, the best prefetch location is prefetch_loc GPU, othervise
2922  * the best prefetch location is always CPU, because GPU can not have coherent
2923  * mapping VRAM of other GPUs even with large-BAR PCIe connection.
2924  *
2925  * For xnack on:
2926  * If range is not ACCESS_IN_PLACE by mGPUs, the best prefetch location is
2927  * prefetch_loc, other GPU access will generate vm fault and trigger migration.
2928  *
2929  * If range is ACCESS_IN_PLACE by mGPUs, only if mGPU connection on XGMI same
2930  * hive, the best prefetch location is prefetch_loc GPU, otherwise the best
2931  * prefetch location is always CPU.
2932  *
2933  * Context: Process context
2934  *
2935  * Return:
2936  * 0 for CPU or GPU id
2937  */
2938 static uint32_t
2939 svm_range_best_prefetch_location(struct svm_range *prange)
2940 {
2941 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
2942 	uint32_t best_loc = prange->prefetch_loc;
2943 	struct kfd_process_device *pdd;
2944 	struct amdgpu_device *bo_adev;
2945 	struct kfd_process *p;
2946 	uint32_t gpuidx;
2947 
2948 	p = container_of(prange->svms, struct kfd_process, svms);
2949 
2950 	if (!best_loc || best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED)
2951 		goto out;
2952 
2953 	bo_adev = svm_range_get_adev_by_id(prange, best_loc);
2954 	if (!bo_adev) {
2955 		WARN_ONCE(1, "failed to get device by id 0x%x\n", best_loc);
2956 		best_loc = 0;
2957 		goto out;
2958 	}
2959 
2960 	if (p->xnack_enabled)
2961 		bitmap_copy(bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
2962 	else
2963 		bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
2964 			  MAX_GPU_INSTANCE);
2965 
2966 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
2967 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
2968 		if (!pdd) {
2969 			pr_debug("failed to get device by idx 0x%x\n", gpuidx);
2970 			continue;
2971 		}
2972 
2973 		if (pdd->dev->adev == bo_adev)
2974 			continue;
2975 
2976 		if (!amdgpu_xgmi_same_hive(pdd->dev->adev, bo_adev)) {
2977 			best_loc = 0;
2978 			break;
2979 		}
2980 	}
2981 
2982 out:
2983 	pr_debug("xnack %d svms 0x%p [0x%lx 0x%lx] best loc 0x%x\n",
2984 		 p->xnack_enabled, &p->svms, prange->start, prange->last,
2985 		 best_loc);
2986 
2987 	return best_loc;
2988 }
2989 
2990 /* FIXME: This is a workaround for page locking bug when some pages are
2991  * invalid during migration to VRAM
2992  */
2993 void svm_range_prefault(struct svm_range *prange, struct mm_struct *mm,
2994 			void *owner)
2995 {
2996 	struct hmm_range *hmm_range;
2997 	int r;
2998 
2999 	if (prange->validated_once)
3000 		return;
3001 
3002 	r = amdgpu_hmm_range_get_pages(&prange->notifier, mm, NULL,
3003 				       prange->start << PAGE_SHIFT,
3004 				       prange->npages, &hmm_range,
3005 				       false, true, owner);
3006 	if (!r) {
3007 		amdgpu_hmm_range_get_pages_done(hmm_range);
3008 		prange->validated_once = true;
3009 	}
3010 }
3011 
3012 /* svm_range_trigger_migration - start page migration if prefetch loc changed
3013  * @mm: current process mm_struct
3014  * @prange: svm range structure
3015  * @migrated: output, true if migration is triggered
3016  *
3017  * If range perfetch_loc is GPU, actual loc is cpu 0, then migrate the range
3018  * from ram to vram.
3019  * If range prefetch_loc is cpu 0, actual loc is GPU, then migrate the range
3020  * from vram to ram.
3021  *
3022  * If GPU vm fault retry is not enabled, migration interact with MMU notifier
3023  * and restore work:
3024  * 1. migrate_vma_setup invalidate pages, MMU notifier callback svm_range_evict
3025  *    stops all queues, schedule restore work
3026  * 2. svm_range_restore_work wait for migration is done by
3027  *    a. svm_range_validate_vram takes prange->migrate_mutex
3028  *    b. svm_range_validate_ram HMM get pages wait for CPU fault handle returns
3029  * 3. restore work update mappings of GPU, resume all queues.
3030  *
3031  * Context: Process context
3032  *
3033  * Return:
3034  * 0 - OK, otherwise - error code of migration
3035  */
3036 static int
3037 svm_range_trigger_migration(struct mm_struct *mm, struct svm_range *prange,
3038 			    bool *migrated)
3039 {
3040 	uint32_t best_loc;
3041 	int r = 0;
3042 
3043 	*migrated = false;
3044 	best_loc = svm_range_best_prefetch_location(prange);
3045 
3046 	if (best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3047 	    best_loc == prange->actual_loc)
3048 		return 0;
3049 
3050 	if (!best_loc) {
3051 		r = svm_migrate_vram_to_ram(prange, mm);
3052 		*migrated = !r;
3053 		return r;
3054 	}
3055 
3056 	r = svm_migrate_to_vram(prange, best_loc, mm);
3057 	*migrated = !r;
3058 
3059 	return r;
3060 }
3061 
3062 int svm_range_schedule_evict_svm_bo(struct amdgpu_amdkfd_fence *fence)
3063 {
3064 	if (!fence)
3065 		return -EINVAL;
3066 
3067 	if (dma_fence_is_signaled(&fence->base))
3068 		return 0;
3069 
3070 	if (fence->svm_bo) {
3071 		WRITE_ONCE(fence->svm_bo->evicting, 1);
3072 		schedule_work(&fence->svm_bo->eviction_work);
3073 	}
3074 
3075 	return 0;
3076 }
3077 
3078 static void svm_range_evict_svm_bo_worker(struct work_struct *work)
3079 {
3080 	struct svm_range_bo *svm_bo;
3081 	struct kfd_process *p;
3082 	struct mm_struct *mm;
3083 
3084 	svm_bo = container_of(work, struct svm_range_bo, eviction_work);
3085 	if (!svm_bo_ref_unless_zero(svm_bo))
3086 		return; /* svm_bo was freed while eviction was pending */
3087 
3088 	/* svm_range_bo_release destroys this worker thread. So during
3089 	 * the lifetime of this thread, kfd_process and mm will be valid.
3090 	 */
3091 	p = container_of(svm_bo->svms, struct kfd_process, svms);
3092 	mm = p->mm;
3093 	if (!mm)
3094 		return;
3095 
3096 	mmap_read_lock(mm);
3097 	spin_lock(&svm_bo->list_lock);
3098 	while (!list_empty(&svm_bo->range_list)) {
3099 		struct svm_range *prange =
3100 				list_first_entry(&svm_bo->range_list,
3101 						struct svm_range, svm_bo_list);
3102 		int retries = 3;
3103 
3104 		list_del_init(&prange->svm_bo_list);
3105 		spin_unlock(&svm_bo->list_lock);
3106 
3107 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
3108 			 prange->start, prange->last);
3109 
3110 		mutex_lock(&prange->migrate_mutex);
3111 		do {
3112 			svm_migrate_vram_to_ram(prange,
3113 						svm_bo->eviction_fence->mm);
3114 		} while (prange->actual_loc && --retries);
3115 		WARN(prange->actual_loc, "Migration failed during eviction");
3116 
3117 		mutex_lock(&prange->lock);
3118 		prange->svm_bo = NULL;
3119 		mutex_unlock(&prange->lock);
3120 
3121 		mutex_unlock(&prange->migrate_mutex);
3122 
3123 		spin_lock(&svm_bo->list_lock);
3124 	}
3125 	spin_unlock(&svm_bo->list_lock);
3126 	mmap_read_unlock(mm);
3127 
3128 	dma_fence_signal(&svm_bo->eviction_fence->base);
3129 	/* This is the last reference to svm_bo, after svm_range_vram_node_free
3130 	 * has been called in svm_migrate_vram_to_ram
3131 	 */
3132 	WARN_ONCE(kref_read(&svm_bo->kref) != 1, "This was not the last reference\n");
3133 	svm_range_bo_unref(svm_bo);
3134 }
3135 
3136 static int
3137 svm_range_set_attr(struct kfd_process *p, uint64_t start, uint64_t size,
3138 		   uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
3139 {
3140 	struct amdkfd_process_info *process_info = p->kgd_process_info;
3141 	struct mm_struct *mm = current->mm;
3142 	struct list_head update_list;
3143 	struct list_head insert_list;
3144 	struct list_head remove_list;
3145 	struct svm_range_list *svms;
3146 	struct svm_range *prange;
3147 	struct svm_range *next;
3148 	int r = 0;
3149 
3150 	pr_debug("pasid 0x%x svms 0x%p [0x%llx 0x%llx] pages 0x%llx\n",
3151 		 p->pasid, &p->svms, start, start + size - 1, size);
3152 
3153 	r = svm_range_check_attr(p, nattr, attrs);
3154 	if (r)
3155 		return r;
3156 
3157 	svms = &p->svms;
3158 
3159 	mutex_lock(&process_info->lock);
3160 
3161 	svm_range_list_lock_and_flush_work(svms, mm);
3162 
3163 	r = svm_range_is_valid(p, start, size);
3164 	if (r) {
3165 		pr_debug("invalid range r=%d\n", r);
3166 		mmap_write_unlock(mm);
3167 		goto out;
3168 	}
3169 
3170 	mutex_lock(&svms->lock);
3171 
3172 	/* Add new range and split existing ranges as needed */
3173 	r = svm_range_add(p, start, size, nattr, attrs, &update_list,
3174 			  &insert_list, &remove_list);
3175 	if (r) {
3176 		mutex_unlock(&svms->lock);
3177 		mmap_write_unlock(mm);
3178 		goto out;
3179 	}
3180 	/* Apply changes as a transaction */
3181 	list_for_each_entry_safe(prange, next, &insert_list, insert_list) {
3182 		svm_range_add_to_svms(prange);
3183 		svm_range_add_notifier_locked(mm, prange);
3184 	}
3185 	list_for_each_entry(prange, &update_list, update_list) {
3186 		svm_range_apply_attrs(p, prange, nattr, attrs);
3187 		/* TODO: unmap ranges from GPU that lost access */
3188 	}
3189 	list_for_each_entry_safe(prange, next, &remove_list,
3190 				remove_list) {
3191 		pr_debug("unlink old 0x%p prange 0x%p [0x%lx 0x%lx]\n",
3192 			 prange->svms, prange, prange->start,
3193 			 prange->last);
3194 		svm_range_unlink(prange);
3195 		svm_range_remove_notifier(prange);
3196 		svm_range_free(prange);
3197 	}
3198 
3199 	mmap_write_downgrade(mm);
3200 	/* Trigger migrations and revalidate and map to GPUs as needed. If
3201 	 * this fails we may be left with partially completed actions. There
3202 	 * is no clean way of rolling back to the previous state in such a
3203 	 * case because the rollback wouldn't be guaranteed to work either.
3204 	 */
3205 	list_for_each_entry(prange, &update_list, update_list) {
3206 		bool migrated;
3207 
3208 		mutex_lock(&prange->migrate_mutex);
3209 
3210 		r = svm_range_trigger_migration(mm, prange, &migrated);
3211 		if (r)
3212 			goto out_unlock_range;
3213 
3214 		if (migrated && !p->xnack_enabled) {
3215 			pr_debug("restore_work will update mappings of GPUs\n");
3216 			mutex_unlock(&prange->migrate_mutex);
3217 			continue;
3218 		}
3219 
3220 		r = svm_range_validate_and_map(mm, prange, MAX_GPU_INSTANCE,
3221 					       true, true);
3222 		if (r)
3223 			pr_debug("failed %d to map svm range\n", r);
3224 
3225 out_unlock_range:
3226 		mutex_unlock(&prange->migrate_mutex);
3227 		if (r)
3228 			break;
3229 	}
3230 
3231 	svm_range_debug_dump(svms);
3232 
3233 	mutex_unlock(&svms->lock);
3234 	mmap_read_unlock(mm);
3235 out:
3236 	mutex_unlock(&process_info->lock);
3237 
3238 	pr_debug("pasid 0x%x svms 0x%p [0x%llx 0x%llx] done, r=%d\n", p->pasid,
3239 		 &p->svms, start, start + size - 1, r);
3240 
3241 	return r;
3242 }
3243 
3244 static int
3245 svm_range_get_attr(struct kfd_process *p, uint64_t start, uint64_t size,
3246 		   uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
3247 {
3248 	DECLARE_BITMAP(bitmap_access, MAX_GPU_INSTANCE);
3249 	DECLARE_BITMAP(bitmap_aip, MAX_GPU_INSTANCE);
3250 	bool get_preferred_loc = false;
3251 	bool get_prefetch_loc = false;
3252 	bool get_granularity = false;
3253 	bool get_accessible = false;
3254 	bool get_flags = false;
3255 	uint64_t last = start + size - 1UL;
3256 	struct mm_struct *mm = current->mm;
3257 	uint8_t granularity = 0xff;
3258 	struct interval_tree_node *node;
3259 	struct svm_range_list *svms;
3260 	struct svm_range *prange;
3261 	uint32_t prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3262 	uint32_t location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3263 	uint32_t flags_and = 0xffffffff;
3264 	uint32_t flags_or = 0;
3265 	int gpuidx;
3266 	uint32_t i;
3267 	int r = 0;
3268 
3269 	pr_debug("svms 0x%p [0x%llx 0x%llx] nattr 0x%x\n", &p->svms, start,
3270 		 start + size - 1, nattr);
3271 
3272 	/* Flush pending deferred work to avoid racing with deferred actions from
3273 	 * previous memory map changes (e.g. munmap). Concurrent memory map changes
3274 	 * can still race with get_attr because we don't hold the mmap lock. But that
3275 	 * would be a race condition in the application anyway, and undefined
3276 	 * behaviour is acceptable in that case.
3277 	 */
3278 	flush_work(&p->svms.deferred_list_work);
3279 
3280 	mmap_read_lock(mm);
3281 	r = svm_range_is_valid(p, start, size);
3282 	mmap_read_unlock(mm);
3283 	if (r) {
3284 		pr_debug("invalid range r=%d\n", r);
3285 		return r;
3286 	}
3287 
3288 	for (i = 0; i < nattr; i++) {
3289 		switch (attrs[i].type) {
3290 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3291 			get_preferred_loc = true;
3292 			break;
3293 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3294 			get_prefetch_loc = true;
3295 			break;
3296 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3297 			get_accessible = true;
3298 			break;
3299 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3300 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3301 			get_flags = true;
3302 			break;
3303 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3304 			get_granularity = true;
3305 			break;
3306 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
3307 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
3308 			fallthrough;
3309 		default:
3310 			pr_debug("get invalid attr type 0x%x\n", attrs[i].type);
3311 			return -EINVAL;
3312 		}
3313 	}
3314 
3315 	svms = &p->svms;
3316 
3317 	mutex_lock(&svms->lock);
3318 
3319 	node = interval_tree_iter_first(&svms->objects, start, last);
3320 	if (!node) {
3321 		pr_debug("range attrs not found return default values\n");
3322 		svm_range_set_default_attributes(&location, &prefetch_loc,
3323 						 &granularity, &flags_and);
3324 		flags_or = flags_and;
3325 		if (p->xnack_enabled)
3326 			bitmap_copy(bitmap_access, svms->bitmap_supported,
3327 				    MAX_GPU_INSTANCE);
3328 		else
3329 			bitmap_zero(bitmap_access, MAX_GPU_INSTANCE);
3330 		bitmap_zero(bitmap_aip, MAX_GPU_INSTANCE);
3331 		goto fill_values;
3332 	}
3333 	bitmap_copy(bitmap_access, svms->bitmap_supported, MAX_GPU_INSTANCE);
3334 	bitmap_copy(bitmap_aip, svms->bitmap_supported, MAX_GPU_INSTANCE);
3335 
3336 	while (node) {
3337 		struct interval_tree_node *next;
3338 
3339 		prange = container_of(node, struct svm_range, it_node);
3340 		next = interval_tree_iter_next(node, start, last);
3341 
3342 		if (get_preferred_loc) {
3343 			if (prange->preferred_loc ==
3344 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3345 			    (location != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3346 			     location != prange->preferred_loc)) {
3347 				location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3348 				get_preferred_loc = false;
3349 			} else {
3350 				location = prange->preferred_loc;
3351 			}
3352 		}
3353 		if (get_prefetch_loc) {
3354 			if (prange->prefetch_loc ==
3355 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3356 			    (prefetch_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3357 			     prefetch_loc != prange->prefetch_loc)) {
3358 				prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3359 				get_prefetch_loc = false;
3360 			} else {
3361 				prefetch_loc = prange->prefetch_loc;
3362 			}
3363 		}
3364 		if (get_accessible) {
3365 			bitmap_and(bitmap_access, bitmap_access,
3366 				   prange->bitmap_access, MAX_GPU_INSTANCE);
3367 			bitmap_and(bitmap_aip, bitmap_aip,
3368 				   prange->bitmap_aip, MAX_GPU_INSTANCE);
3369 		}
3370 		if (get_flags) {
3371 			flags_and &= prange->flags;
3372 			flags_or |= prange->flags;
3373 		}
3374 
3375 		if (get_granularity && prange->granularity < granularity)
3376 			granularity = prange->granularity;
3377 
3378 		node = next;
3379 	}
3380 fill_values:
3381 	mutex_unlock(&svms->lock);
3382 
3383 	for (i = 0; i < nattr; i++) {
3384 		switch (attrs[i].type) {
3385 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3386 			attrs[i].value = location;
3387 			break;
3388 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3389 			attrs[i].value = prefetch_loc;
3390 			break;
3391 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3392 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
3393 							       attrs[i].value);
3394 			if (gpuidx < 0) {
3395 				pr_debug("invalid gpuid %x\n", attrs[i].value);
3396 				return -EINVAL;
3397 			}
3398 			if (test_bit(gpuidx, bitmap_access))
3399 				attrs[i].type = KFD_IOCTL_SVM_ATTR_ACCESS;
3400 			else if (test_bit(gpuidx, bitmap_aip))
3401 				attrs[i].type =
3402 					KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE;
3403 			else
3404 				attrs[i].type = KFD_IOCTL_SVM_ATTR_NO_ACCESS;
3405 			break;
3406 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3407 			attrs[i].value = flags_and;
3408 			break;
3409 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3410 			attrs[i].value = ~flags_or;
3411 			break;
3412 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3413 			attrs[i].value = (uint32_t)granularity;
3414 			break;
3415 		}
3416 	}
3417 
3418 	return 0;
3419 }
3420 
3421 int
3422 svm_ioctl(struct kfd_process *p, enum kfd_ioctl_svm_op op, uint64_t start,
3423 	  uint64_t size, uint32_t nattrs, struct kfd_ioctl_svm_attribute *attrs)
3424 {
3425 	int r;
3426 
3427 	start >>= PAGE_SHIFT;
3428 	size >>= PAGE_SHIFT;
3429 
3430 	switch (op) {
3431 	case KFD_IOCTL_SVM_OP_SET_ATTR:
3432 		r = svm_range_set_attr(p, start, size, nattrs, attrs);
3433 		break;
3434 	case KFD_IOCTL_SVM_OP_GET_ATTR:
3435 		r = svm_range_get_attr(p, start, size, nattrs, attrs);
3436 		break;
3437 	default:
3438 		r = EINVAL;
3439 		break;
3440 	}
3441 
3442 	return r;
3443 }
3444