xref: /openbmc/linux/drivers/gpu/drm/amd/amdkfd/kfd_svm.c (revision 56b5b1c7)
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 struct criu_svm_metadata {
49 	struct list_head list;
50 	struct kfd_criu_svm_range_priv_data data;
51 };
52 
53 static void svm_range_evict_svm_bo_worker(struct work_struct *work);
54 static bool
55 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
56 				    const struct mmu_notifier_range *range,
57 				    unsigned long cur_seq);
58 static int
59 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
60 		   uint64_t *bo_s, uint64_t *bo_l);
61 static const struct mmu_interval_notifier_ops svm_range_mn_ops = {
62 	.invalidate = svm_range_cpu_invalidate_pagetables,
63 };
64 
65 /**
66  * svm_range_unlink - unlink svm_range from lists and interval tree
67  * @prange: svm range structure to be removed
68  *
69  * Remove the svm_range from the svms and svm_bo lists and the svms
70  * interval tree.
71  *
72  * Context: The caller must hold svms->lock
73  */
74 static void svm_range_unlink(struct svm_range *prange)
75 {
76 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
77 		 prange, prange->start, prange->last);
78 
79 	if (prange->svm_bo) {
80 		spin_lock(&prange->svm_bo->list_lock);
81 		list_del(&prange->svm_bo_list);
82 		spin_unlock(&prange->svm_bo->list_lock);
83 	}
84 
85 	list_del(&prange->list);
86 	if (prange->it_node.start != 0 && prange->it_node.last != 0)
87 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
88 }
89 
90 static void
91 svm_range_add_notifier_locked(struct mm_struct *mm, struct svm_range *prange)
92 {
93 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
94 		 prange, prange->start, prange->last);
95 
96 	mmu_interval_notifier_insert_locked(&prange->notifier, mm,
97 				     prange->start << PAGE_SHIFT,
98 				     prange->npages << PAGE_SHIFT,
99 				     &svm_range_mn_ops);
100 }
101 
102 /**
103  * svm_range_add_to_svms - add svm range to svms
104  * @prange: svm range structure to be added
105  *
106  * Add the svm range to svms interval tree and link list
107  *
108  * Context: The caller must hold svms->lock
109  */
110 static void svm_range_add_to_svms(struct svm_range *prange)
111 {
112 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
113 		 prange, prange->start, prange->last);
114 
115 	list_move_tail(&prange->list, &prange->svms->list);
116 	prange->it_node.start = prange->start;
117 	prange->it_node.last = prange->last;
118 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
119 }
120 
121 static void svm_range_remove_notifier(struct svm_range *prange)
122 {
123 	pr_debug("remove notifier svms 0x%p prange 0x%p [0x%lx 0x%lx]\n",
124 		 prange->svms, prange,
125 		 prange->notifier.interval_tree.start >> PAGE_SHIFT,
126 		 prange->notifier.interval_tree.last >> PAGE_SHIFT);
127 
128 	if (prange->notifier.interval_tree.start != 0 &&
129 	    prange->notifier.interval_tree.last != 0)
130 		mmu_interval_notifier_remove(&prange->notifier);
131 }
132 
133 static bool
134 svm_is_valid_dma_mapping_addr(struct device *dev, dma_addr_t dma_addr)
135 {
136 	return dma_addr && !dma_mapping_error(dev, dma_addr) &&
137 	       !(dma_addr & SVM_RANGE_VRAM_DOMAIN);
138 }
139 
140 static int
141 svm_range_dma_map_dev(struct amdgpu_device *adev, struct svm_range *prange,
142 		      unsigned long offset, unsigned long npages,
143 		      unsigned long *hmm_pfns, uint32_t gpuidx)
144 {
145 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
146 	dma_addr_t *addr = prange->dma_addr[gpuidx];
147 	struct device *dev = adev->dev;
148 	struct page *page;
149 	int i, r;
150 
151 	if (!addr) {
152 		addr = kvmalloc_array(prange->npages, sizeof(*addr),
153 				      GFP_KERNEL | __GFP_ZERO);
154 		if (!addr)
155 			return -ENOMEM;
156 		prange->dma_addr[gpuidx] = addr;
157 	}
158 
159 	addr += offset;
160 	for (i = 0; i < npages; i++) {
161 		if (svm_is_valid_dma_mapping_addr(dev, addr[i]))
162 			dma_unmap_page(dev, addr[i], PAGE_SIZE, dir);
163 
164 		page = hmm_pfn_to_page(hmm_pfns[i]);
165 		if (is_zone_device_page(page)) {
166 			struct amdgpu_device *bo_adev =
167 					amdgpu_ttm_adev(prange->svm_bo->bo->tbo.bdev);
168 
169 			addr[i] = (hmm_pfns[i] << PAGE_SHIFT) +
170 				   bo_adev->vm_manager.vram_base_offset -
171 				   bo_adev->kfd.dev->pgmap.range.start;
172 			addr[i] |= SVM_RANGE_VRAM_DOMAIN;
173 			pr_debug_ratelimited("vram address: 0x%llx\n", addr[i]);
174 			continue;
175 		}
176 		addr[i] = dma_map_page(dev, page, 0, PAGE_SIZE, dir);
177 		r = dma_mapping_error(dev, addr[i]);
178 		if (r) {
179 			dev_err(dev, "failed %d dma_map_page\n", r);
180 			return r;
181 		}
182 		pr_debug_ratelimited("dma mapping 0x%llx for page addr 0x%lx\n",
183 				     addr[i] >> PAGE_SHIFT, page_to_pfn(page));
184 	}
185 	return 0;
186 }
187 
188 static int
189 svm_range_dma_map(struct svm_range *prange, unsigned long *bitmap,
190 		  unsigned long offset, unsigned long npages,
191 		  unsigned long *hmm_pfns)
192 {
193 	struct kfd_process *p;
194 	uint32_t gpuidx;
195 	int r;
196 
197 	p = container_of(prange->svms, struct kfd_process, svms);
198 
199 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
200 		struct kfd_process_device *pdd;
201 
202 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
203 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
204 		if (!pdd) {
205 			pr_debug("failed to find device idx %d\n", gpuidx);
206 			return -EINVAL;
207 		}
208 
209 		r = svm_range_dma_map_dev(pdd->dev->adev, prange, offset, npages,
210 					  hmm_pfns, gpuidx);
211 		if (r)
212 			break;
213 	}
214 
215 	return r;
216 }
217 
218 void svm_range_dma_unmap(struct device *dev, dma_addr_t *dma_addr,
219 			 unsigned long offset, unsigned long npages)
220 {
221 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
222 	int i;
223 
224 	if (!dma_addr)
225 		return;
226 
227 	for (i = offset; i < offset + npages; i++) {
228 		if (!svm_is_valid_dma_mapping_addr(dev, dma_addr[i]))
229 			continue;
230 		pr_debug_ratelimited("unmap 0x%llx\n", dma_addr[i] >> PAGE_SHIFT);
231 		dma_unmap_page(dev, dma_addr[i], PAGE_SIZE, dir);
232 		dma_addr[i] = 0;
233 	}
234 }
235 
236 void svm_range_free_dma_mappings(struct svm_range *prange)
237 {
238 	struct kfd_process_device *pdd;
239 	dma_addr_t *dma_addr;
240 	struct device *dev;
241 	struct kfd_process *p;
242 	uint32_t gpuidx;
243 
244 	p = container_of(prange->svms, struct kfd_process, svms);
245 
246 	for (gpuidx = 0; gpuidx < MAX_GPU_INSTANCE; gpuidx++) {
247 		dma_addr = prange->dma_addr[gpuidx];
248 		if (!dma_addr)
249 			continue;
250 
251 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
252 		if (!pdd) {
253 			pr_debug("failed to find device idx %d\n", gpuidx);
254 			continue;
255 		}
256 		dev = &pdd->dev->pdev->dev;
257 		svm_range_dma_unmap(dev, dma_addr, 0, prange->npages);
258 		kvfree(dma_addr);
259 		prange->dma_addr[gpuidx] = NULL;
260 	}
261 }
262 
263 static void svm_range_free(struct svm_range *prange)
264 {
265 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms, prange,
266 		 prange->start, prange->last);
267 
268 	svm_range_vram_node_free(prange);
269 	svm_range_free_dma_mappings(prange);
270 	mutex_destroy(&prange->lock);
271 	mutex_destroy(&prange->migrate_mutex);
272 	kfree(prange);
273 }
274 
275 static void
276 svm_range_set_default_attributes(int32_t *location, int32_t *prefetch_loc,
277 				 uint8_t *granularity, uint32_t *flags)
278 {
279 	*location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
280 	*prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
281 	*granularity = 9;
282 	*flags =
283 		KFD_IOCTL_SVM_FLAG_HOST_ACCESS | KFD_IOCTL_SVM_FLAG_COHERENT;
284 }
285 
286 static struct
287 svm_range *svm_range_new(struct svm_range_list *svms, uint64_t start,
288 			 uint64_t last)
289 {
290 	uint64_t size = last - start + 1;
291 	struct svm_range *prange;
292 	struct kfd_process *p;
293 
294 	prange = kzalloc(sizeof(*prange), GFP_KERNEL);
295 	if (!prange)
296 		return NULL;
297 	prange->npages = size;
298 	prange->svms = svms;
299 	prange->start = start;
300 	prange->last = last;
301 	INIT_LIST_HEAD(&prange->list);
302 	INIT_LIST_HEAD(&prange->update_list);
303 	INIT_LIST_HEAD(&prange->svm_bo_list);
304 	INIT_LIST_HEAD(&prange->deferred_list);
305 	INIT_LIST_HEAD(&prange->child_list);
306 	atomic_set(&prange->invalid, 0);
307 	prange->validate_timestamp = 0;
308 	mutex_init(&prange->migrate_mutex);
309 	mutex_init(&prange->lock);
310 
311 	p = container_of(svms, struct kfd_process, svms);
312 	if (p->xnack_enabled)
313 		bitmap_copy(prange->bitmap_access, svms->bitmap_supported,
314 			    MAX_GPU_INSTANCE);
315 
316 	svm_range_set_default_attributes(&prange->preferred_loc,
317 					 &prange->prefetch_loc,
318 					 &prange->granularity, &prange->flags);
319 
320 	pr_debug("svms 0x%p [0x%llx 0x%llx]\n", svms, start, last);
321 
322 	return prange;
323 }
324 
325 static bool svm_bo_ref_unless_zero(struct svm_range_bo *svm_bo)
326 {
327 	if (!svm_bo || !kref_get_unless_zero(&svm_bo->kref))
328 		return false;
329 
330 	return true;
331 }
332 
333 static void svm_range_bo_release(struct kref *kref)
334 {
335 	struct svm_range_bo *svm_bo;
336 
337 	svm_bo = container_of(kref, struct svm_range_bo, kref);
338 	pr_debug("svm_bo 0x%p\n", svm_bo);
339 
340 	spin_lock(&svm_bo->list_lock);
341 	while (!list_empty(&svm_bo->range_list)) {
342 		struct svm_range *prange =
343 				list_first_entry(&svm_bo->range_list,
344 						struct svm_range, svm_bo_list);
345 		/* list_del_init tells a concurrent svm_range_vram_node_new when
346 		 * it's safe to reuse the svm_bo pointer and svm_bo_list head.
347 		 */
348 		list_del_init(&prange->svm_bo_list);
349 		spin_unlock(&svm_bo->list_lock);
350 
351 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
352 			 prange->start, prange->last);
353 		mutex_lock(&prange->lock);
354 		prange->svm_bo = NULL;
355 		mutex_unlock(&prange->lock);
356 
357 		spin_lock(&svm_bo->list_lock);
358 	}
359 	spin_unlock(&svm_bo->list_lock);
360 	if (!dma_fence_is_signaled(&svm_bo->eviction_fence->base)) {
361 		/* We're not in the eviction worker.
362 		 * Signal the fence and synchronize with any
363 		 * pending eviction work.
364 		 */
365 		dma_fence_signal(&svm_bo->eviction_fence->base);
366 		cancel_work_sync(&svm_bo->eviction_work);
367 	}
368 	dma_fence_put(&svm_bo->eviction_fence->base);
369 	amdgpu_bo_unref(&svm_bo->bo);
370 	kfree(svm_bo);
371 }
372 
373 static void svm_range_bo_wq_release(struct work_struct *work)
374 {
375 	struct svm_range_bo *svm_bo;
376 
377 	svm_bo = container_of(work, struct svm_range_bo, release_work);
378 	svm_range_bo_release(&svm_bo->kref);
379 }
380 
381 static void svm_range_bo_release_async(struct kref *kref)
382 {
383 	struct svm_range_bo *svm_bo;
384 
385 	svm_bo = container_of(kref, struct svm_range_bo, kref);
386 	pr_debug("svm_bo 0x%p\n", svm_bo);
387 	INIT_WORK(&svm_bo->release_work, svm_range_bo_wq_release);
388 	schedule_work(&svm_bo->release_work);
389 }
390 
391 void svm_range_bo_unref_async(struct svm_range_bo *svm_bo)
392 {
393 	kref_put(&svm_bo->kref, svm_range_bo_release_async);
394 }
395 
396 static void svm_range_bo_unref(struct svm_range_bo *svm_bo)
397 {
398 	if (svm_bo)
399 		kref_put(&svm_bo->kref, svm_range_bo_release);
400 }
401 
402 static bool
403 svm_range_validate_svm_bo(struct amdgpu_device *adev, struct svm_range *prange)
404 {
405 	struct amdgpu_device *bo_adev;
406 
407 	mutex_lock(&prange->lock);
408 	if (!prange->svm_bo) {
409 		mutex_unlock(&prange->lock);
410 		return false;
411 	}
412 	if (prange->ttm_res) {
413 		/* We still have a reference, all is well */
414 		mutex_unlock(&prange->lock);
415 		return true;
416 	}
417 	if (svm_bo_ref_unless_zero(prange->svm_bo)) {
418 		/*
419 		 * Migrate from GPU to GPU, remove range from source bo_adev
420 		 * svm_bo range list, and return false to allocate svm_bo from
421 		 * destination adev.
422 		 */
423 		bo_adev = amdgpu_ttm_adev(prange->svm_bo->bo->tbo.bdev);
424 		if (bo_adev != adev) {
425 			mutex_unlock(&prange->lock);
426 
427 			spin_lock(&prange->svm_bo->list_lock);
428 			list_del_init(&prange->svm_bo_list);
429 			spin_unlock(&prange->svm_bo->list_lock);
430 
431 			svm_range_bo_unref(prange->svm_bo);
432 			return false;
433 		}
434 		if (READ_ONCE(prange->svm_bo->evicting)) {
435 			struct dma_fence *f;
436 			struct svm_range_bo *svm_bo;
437 			/* The BO is getting evicted,
438 			 * we need to get a new one
439 			 */
440 			mutex_unlock(&prange->lock);
441 			svm_bo = prange->svm_bo;
442 			f = dma_fence_get(&svm_bo->eviction_fence->base);
443 			svm_range_bo_unref(prange->svm_bo);
444 			/* wait for the fence to avoid long spin-loop
445 			 * at list_empty_careful
446 			 */
447 			dma_fence_wait(f, false);
448 			dma_fence_put(f);
449 		} else {
450 			/* The BO was still around and we got
451 			 * a new reference to it
452 			 */
453 			mutex_unlock(&prange->lock);
454 			pr_debug("reuse old bo svms 0x%p [0x%lx 0x%lx]\n",
455 				 prange->svms, prange->start, prange->last);
456 
457 			prange->ttm_res = prange->svm_bo->bo->tbo.resource;
458 			return true;
459 		}
460 
461 	} else {
462 		mutex_unlock(&prange->lock);
463 	}
464 
465 	/* We need a new svm_bo. Spin-loop to wait for concurrent
466 	 * svm_range_bo_release to finish removing this range from
467 	 * its range list. After this, it is safe to reuse the
468 	 * svm_bo pointer and svm_bo_list head.
469 	 */
470 	while (!list_empty_careful(&prange->svm_bo_list))
471 		;
472 
473 	return false;
474 }
475 
476 static struct svm_range_bo *svm_range_bo_new(void)
477 {
478 	struct svm_range_bo *svm_bo;
479 
480 	svm_bo = kzalloc(sizeof(*svm_bo), GFP_KERNEL);
481 	if (!svm_bo)
482 		return NULL;
483 
484 	kref_init(&svm_bo->kref);
485 	INIT_LIST_HEAD(&svm_bo->range_list);
486 	spin_lock_init(&svm_bo->list_lock);
487 
488 	return svm_bo;
489 }
490 
491 int
492 svm_range_vram_node_new(struct amdgpu_device *adev, struct svm_range *prange,
493 			bool clear)
494 {
495 	struct amdgpu_bo_param bp;
496 	struct svm_range_bo *svm_bo;
497 	struct amdgpu_bo_user *ubo;
498 	struct amdgpu_bo *bo;
499 	struct kfd_process *p;
500 	struct mm_struct *mm;
501 	int r;
502 
503 	p = container_of(prange->svms, struct kfd_process, svms);
504 	pr_debug("pasid: %x svms 0x%p [0x%lx 0x%lx]\n", p->pasid, prange->svms,
505 		 prange->start, prange->last);
506 
507 	if (svm_range_validate_svm_bo(adev, prange))
508 		return 0;
509 
510 	svm_bo = svm_range_bo_new();
511 	if (!svm_bo) {
512 		pr_debug("failed to alloc svm bo\n");
513 		return -ENOMEM;
514 	}
515 	mm = get_task_mm(p->lead_thread);
516 	if (!mm) {
517 		pr_debug("failed to get mm\n");
518 		kfree(svm_bo);
519 		return -ESRCH;
520 	}
521 	svm_bo->svms = prange->svms;
522 	svm_bo->eviction_fence =
523 		amdgpu_amdkfd_fence_create(dma_fence_context_alloc(1),
524 					   mm,
525 					   svm_bo);
526 	mmput(mm);
527 	INIT_WORK(&svm_bo->eviction_work, svm_range_evict_svm_bo_worker);
528 	svm_bo->evicting = 0;
529 	memset(&bp, 0, sizeof(bp));
530 	bp.size = prange->npages * PAGE_SIZE;
531 	bp.byte_align = PAGE_SIZE;
532 	bp.domain = AMDGPU_GEM_DOMAIN_VRAM;
533 	bp.flags = AMDGPU_GEM_CREATE_NO_CPU_ACCESS;
534 	bp.flags |= clear ? AMDGPU_GEM_CREATE_VRAM_CLEARED : 0;
535 	bp.flags |= AMDGPU_AMDKFD_CREATE_SVM_BO;
536 	bp.type = ttm_bo_type_device;
537 	bp.resv = NULL;
538 
539 	r = amdgpu_bo_create_user(adev, &bp, &ubo);
540 	if (r) {
541 		pr_debug("failed %d to create bo\n", r);
542 		goto create_bo_failed;
543 	}
544 	bo = &ubo->bo;
545 	r = amdgpu_bo_reserve(bo, true);
546 	if (r) {
547 		pr_debug("failed %d to reserve bo\n", r);
548 		goto reserve_bo_failed;
549 	}
550 
551 	r = dma_resv_reserve_shared(bo->tbo.base.resv, 1);
552 	if (r) {
553 		pr_debug("failed %d to reserve bo\n", r);
554 		amdgpu_bo_unreserve(bo);
555 		goto reserve_bo_failed;
556 	}
557 	amdgpu_bo_fence(bo, &svm_bo->eviction_fence->base, true);
558 
559 	amdgpu_bo_unreserve(bo);
560 
561 	svm_bo->bo = bo;
562 	prange->svm_bo = svm_bo;
563 	prange->ttm_res = bo->tbo.resource;
564 	prange->offset = 0;
565 
566 	spin_lock(&svm_bo->list_lock);
567 	list_add(&prange->svm_bo_list, &svm_bo->range_list);
568 	spin_unlock(&svm_bo->list_lock);
569 
570 	return 0;
571 
572 reserve_bo_failed:
573 	amdgpu_bo_unref(&bo);
574 create_bo_failed:
575 	dma_fence_put(&svm_bo->eviction_fence->base);
576 	kfree(svm_bo);
577 	prange->ttm_res = NULL;
578 
579 	return r;
580 }
581 
582 void svm_range_vram_node_free(struct svm_range *prange)
583 {
584 	svm_range_bo_unref(prange->svm_bo);
585 	prange->ttm_res = NULL;
586 }
587 
588 struct amdgpu_device *
589 svm_range_get_adev_by_id(struct svm_range *prange, uint32_t gpu_id)
590 {
591 	struct kfd_process_device *pdd;
592 	struct kfd_process *p;
593 	int32_t gpu_idx;
594 
595 	p = container_of(prange->svms, struct kfd_process, svms);
596 
597 	gpu_idx = kfd_process_gpuidx_from_gpuid(p, gpu_id);
598 	if (gpu_idx < 0) {
599 		pr_debug("failed to get device by id 0x%x\n", gpu_id);
600 		return NULL;
601 	}
602 	pdd = kfd_process_device_from_gpuidx(p, gpu_idx);
603 	if (!pdd) {
604 		pr_debug("failed to get device by idx 0x%x\n", gpu_idx);
605 		return NULL;
606 	}
607 
608 	return pdd->dev->adev;
609 }
610 
611 struct kfd_process_device *
612 svm_range_get_pdd_by_adev(struct svm_range *prange, struct amdgpu_device *adev)
613 {
614 	struct kfd_process *p;
615 	int32_t gpu_idx, gpuid;
616 	int r;
617 
618 	p = container_of(prange->svms, struct kfd_process, svms);
619 
620 	r = kfd_process_gpuid_from_adev(p, adev, &gpuid, &gpu_idx);
621 	if (r) {
622 		pr_debug("failed to get device id by adev %p\n", adev);
623 		return NULL;
624 	}
625 
626 	return kfd_process_device_from_gpuidx(p, gpu_idx);
627 }
628 
629 static int svm_range_bo_validate(void *param, struct amdgpu_bo *bo)
630 {
631 	struct ttm_operation_ctx ctx = { false, false };
632 
633 	amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_VRAM);
634 
635 	return ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
636 }
637 
638 static int
639 svm_range_check_attr(struct kfd_process *p,
640 		     uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
641 {
642 	uint32_t i;
643 
644 	for (i = 0; i < nattr; i++) {
645 		uint32_t val = attrs[i].value;
646 		int gpuidx = MAX_GPU_INSTANCE;
647 
648 		switch (attrs[i].type) {
649 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
650 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM &&
651 			    val != KFD_IOCTL_SVM_LOCATION_UNDEFINED)
652 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
653 			break;
654 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
655 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM)
656 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
657 			break;
658 		case KFD_IOCTL_SVM_ATTR_ACCESS:
659 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
660 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
661 			gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
662 			break;
663 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
664 			break;
665 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
666 			break;
667 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
668 			break;
669 		default:
670 			pr_debug("unknown attr type 0x%x\n", attrs[i].type);
671 			return -EINVAL;
672 		}
673 
674 		if (gpuidx < 0) {
675 			pr_debug("no GPU 0x%x found\n", val);
676 			return -EINVAL;
677 		} else if (gpuidx < MAX_GPU_INSTANCE &&
678 			   !test_bit(gpuidx, p->svms.bitmap_supported)) {
679 			pr_debug("GPU 0x%x not supported\n", val);
680 			return -EINVAL;
681 		}
682 	}
683 
684 	return 0;
685 }
686 
687 static void
688 svm_range_apply_attrs(struct kfd_process *p, struct svm_range *prange,
689 		      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
690 {
691 	uint32_t i;
692 	int gpuidx;
693 
694 	for (i = 0; i < nattr; i++) {
695 		switch (attrs[i].type) {
696 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
697 			prange->preferred_loc = attrs[i].value;
698 			break;
699 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
700 			prange->prefetch_loc = attrs[i].value;
701 			break;
702 		case KFD_IOCTL_SVM_ATTR_ACCESS:
703 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
704 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
705 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
706 							       attrs[i].value);
707 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
708 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
709 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
710 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
711 				bitmap_set(prange->bitmap_access, gpuidx, 1);
712 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
713 			} else {
714 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
715 				bitmap_set(prange->bitmap_aip, gpuidx, 1);
716 			}
717 			break;
718 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
719 			prange->flags |= attrs[i].value;
720 			break;
721 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
722 			prange->flags &= ~attrs[i].value;
723 			break;
724 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
725 			prange->granularity = attrs[i].value;
726 			break;
727 		default:
728 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
729 		}
730 	}
731 }
732 
733 static bool
734 svm_range_is_same_attrs(struct kfd_process *p, struct svm_range *prange,
735 			uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
736 {
737 	uint32_t i;
738 	int gpuidx;
739 
740 	for (i = 0; i < nattr; i++) {
741 		switch (attrs[i].type) {
742 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
743 			if (prange->preferred_loc != attrs[i].value)
744 				return false;
745 			break;
746 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
747 			/* Prefetch should always trigger a migration even
748 			 * if the value of the attribute didn't change.
749 			 */
750 			return false;
751 		case KFD_IOCTL_SVM_ATTR_ACCESS:
752 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
753 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
754 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
755 							       attrs[i].value);
756 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
757 				if (test_bit(gpuidx, prange->bitmap_access) ||
758 				    test_bit(gpuidx, prange->bitmap_aip))
759 					return false;
760 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
761 				if (!test_bit(gpuidx, prange->bitmap_access))
762 					return false;
763 			} else {
764 				if (!test_bit(gpuidx, prange->bitmap_aip))
765 					return false;
766 			}
767 			break;
768 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
769 			if ((prange->flags & attrs[i].value) != attrs[i].value)
770 				return false;
771 			break;
772 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
773 			if ((prange->flags & attrs[i].value) != 0)
774 				return false;
775 			break;
776 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
777 			if (prange->granularity != attrs[i].value)
778 				return false;
779 			break;
780 		default:
781 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
782 		}
783 	}
784 
785 	return true;
786 }
787 
788 /**
789  * svm_range_debug_dump - print all range information from svms
790  * @svms: svm range list header
791  *
792  * debug output svm range start, end, prefetch location from svms
793  * interval tree and link list
794  *
795  * Context: The caller must hold svms->lock
796  */
797 static void svm_range_debug_dump(struct svm_range_list *svms)
798 {
799 	struct interval_tree_node *node;
800 	struct svm_range *prange;
801 
802 	pr_debug("dump svms 0x%p list\n", svms);
803 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
804 
805 	list_for_each_entry(prange, &svms->list, list) {
806 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
807 			 prange, prange->start, prange->npages,
808 			 prange->start + prange->npages - 1,
809 			 prange->actual_loc);
810 	}
811 
812 	pr_debug("dump svms 0x%p interval tree\n", svms);
813 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
814 	node = interval_tree_iter_first(&svms->objects, 0, ~0ULL);
815 	while (node) {
816 		prange = container_of(node, struct svm_range, it_node);
817 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
818 			 prange, prange->start, prange->npages,
819 			 prange->start + prange->npages - 1,
820 			 prange->actual_loc);
821 		node = interval_tree_iter_next(node, 0, ~0ULL);
822 	}
823 }
824 
825 static int
826 svm_range_split_array(void *ppnew, void *ppold, size_t size,
827 		      uint64_t old_start, uint64_t old_n,
828 		      uint64_t new_start, uint64_t new_n)
829 {
830 	unsigned char *new, *old, *pold;
831 	uint64_t d;
832 
833 	if (!ppold)
834 		return 0;
835 	pold = *(unsigned char **)ppold;
836 	if (!pold)
837 		return 0;
838 
839 	new = kvmalloc_array(new_n, size, GFP_KERNEL);
840 	if (!new)
841 		return -ENOMEM;
842 
843 	d = (new_start - old_start) * size;
844 	memcpy(new, pold + d, new_n * size);
845 
846 	old = kvmalloc_array(old_n, size, GFP_KERNEL);
847 	if (!old) {
848 		kvfree(new);
849 		return -ENOMEM;
850 	}
851 
852 	d = (new_start == old_start) ? new_n * size : 0;
853 	memcpy(old, pold + d, old_n * size);
854 
855 	kvfree(pold);
856 	*(void **)ppold = old;
857 	*(void **)ppnew = new;
858 
859 	return 0;
860 }
861 
862 static int
863 svm_range_split_pages(struct svm_range *new, struct svm_range *old,
864 		      uint64_t start, uint64_t last)
865 {
866 	uint64_t npages = last - start + 1;
867 	int i, r;
868 
869 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
870 		r = svm_range_split_array(&new->dma_addr[i], &old->dma_addr[i],
871 					  sizeof(*old->dma_addr[i]), old->start,
872 					  npages, new->start, new->npages);
873 		if (r)
874 			return r;
875 	}
876 
877 	return 0;
878 }
879 
880 static int
881 svm_range_split_nodes(struct svm_range *new, struct svm_range *old,
882 		      uint64_t start, uint64_t last)
883 {
884 	uint64_t npages = last - start + 1;
885 
886 	pr_debug("svms 0x%p new prange 0x%p start 0x%lx [0x%llx 0x%llx]\n",
887 		 new->svms, new, new->start, start, last);
888 
889 	if (new->start == old->start) {
890 		new->offset = old->offset;
891 		old->offset += new->npages;
892 	} else {
893 		new->offset = old->offset + npages;
894 	}
895 
896 	new->svm_bo = svm_range_bo_ref(old->svm_bo);
897 	new->ttm_res = old->ttm_res;
898 
899 	spin_lock(&new->svm_bo->list_lock);
900 	list_add(&new->svm_bo_list, &new->svm_bo->range_list);
901 	spin_unlock(&new->svm_bo->list_lock);
902 
903 	return 0;
904 }
905 
906 /**
907  * svm_range_split_adjust - split range and adjust
908  *
909  * @new: new range
910  * @old: the old range
911  * @start: the old range adjust to start address in pages
912  * @last: the old range adjust to last address in pages
913  *
914  * Copy system memory dma_addr or vram ttm_res in old range to new
915  * range from new_start up to size new->npages, the remaining old range is from
916  * start to last
917  *
918  * Return:
919  * 0 - OK, -ENOMEM - out of memory
920  */
921 static int
922 svm_range_split_adjust(struct svm_range *new, struct svm_range *old,
923 		      uint64_t start, uint64_t last)
924 {
925 	int r;
926 
927 	pr_debug("svms 0x%p new 0x%lx old [0x%lx 0x%lx] => [0x%llx 0x%llx]\n",
928 		 new->svms, new->start, old->start, old->last, start, last);
929 
930 	if (new->start < old->start ||
931 	    new->last > old->last) {
932 		WARN_ONCE(1, "invalid new range start or last\n");
933 		return -EINVAL;
934 	}
935 
936 	r = svm_range_split_pages(new, old, start, last);
937 	if (r)
938 		return r;
939 
940 	if (old->actual_loc && old->ttm_res) {
941 		r = svm_range_split_nodes(new, old, start, last);
942 		if (r)
943 			return r;
944 	}
945 
946 	old->npages = last - start + 1;
947 	old->start = start;
948 	old->last = last;
949 	new->flags = old->flags;
950 	new->preferred_loc = old->preferred_loc;
951 	new->prefetch_loc = old->prefetch_loc;
952 	new->actual_loc = old->actual_loc;
953 	new->granularity = old->granularity;
954 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
955 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
956 
957 	return 0;
958 }
959 
960 /**
961  * svm_range_split - split a range in 2 ranges
962  *
963  * @prange: the svm range to split
964  * @start: the remaining range start address in pages
965  * @last: the remaining range last address in pages
966  * @new: the result new range generated
967  *
968  * Two cases only:
969  * case 1: if start == prange->start
970  *         prange ==> prange[start, last]
971  *         new range [last + 1, prange->last]
972  *
973  * case 2: if last == prange->last
974  *         prange ==> prange[start, last]
975  *         new range [prange->start, start - 1]
976  *
977  * Return:
978  * 0 - OK, -ENOMEM - out of memory, -EINVAL - invalid start, last
979  */
980 static int
981 svm_range_split(struct svm_range *prange, uint64_t start, uint64_t last,
982 		struct svm_range **new)
983 {
984 	uint64_t old_start = prange->start;
985 	uint64_t old_last = prange->last;
986 	struct svm_range_list *svms;
987 	int r = 0;
988 
989 	pr_debug("svms 0x%p [0x%llx 0x%llx] to [0x%llx 0x%llx]\n", prange->svms,
990 		 old_start, old_last, start, last);
991 
992 	if (old_start != start && old_last != last)
993 		return -EINVAL;
994 	if (start < old_start || last > old_last)
995 		return -EINVAL;
996 
997 	svms = prange->svms;
998 	if (old_start == start)
999 		*new = svm_range_new(svms, last + 1, old_last);
1000 	else
1001 		*new = svm_range_new(svms, old_start, start - 1);
1002 	if (!*new)
1003 		return -ENOMEM;
1004 
1005 	r = svm_range_split_adjust(*new, prange, start, last);
1006 	if (r) {
1007 		pr_debug("failed %d split [0x%llx 0x%llx] to [0x%llx 0x%llx]\n",
1008 			 r, old_start, old_last, start, last);
1009 		svm_range_free(*new);
1010 		*new = NULL;
1011 	}
1012 
1013 	return r;
1014 }
1015 
1016 static int
1017 svm_range_split_tail(struct svm_range *prange,
1018 		     uint64_t new_last, struct list_head *insert_list)
1019 {
1020 	struct svm_range *tail;
1021 	int r = svm_range_split(prange, prange->start, new_last, &tail);
1022 
1023 	if (!r)
1024 		list_add(&tail->list, insert_list);
1025 	return r;
1026 }
1027 
1028 static int
1029 svm_range_split_head(struct svm_range *prange,
1030 		     uint64_t new_start, struct list_head *insert_list)
1031 {
1032 	struct svm_range *head;
1033 	int r = svm_range_split(prange, new_start, prange->last, &head);
1034 
1035 	if (!r)
1036 		list_add(&head->list, insert_list);
1037 	return r;
1038 }
1039 
1040 static void
1041 svm_range_add_child(struct svm_range *prange, struct mm_struct *mm,
1042 		    struct svm_range *pchild, enum svm_work_list_ops op)
1043 {
1044 	pr_debug("add child 0x%p [0x%lx 0x%lx] to prange 0x%p child list %d\n",
1045 		 pchild, pchild->start, pchild->last, prange, op);
1046 
1047 	pchild->work_item.mm = mm;
1048 	pchild->work_item.op = op;
1049 	list_add_tail(&pchild->child_list, &prange->child_list);
1050 }
1051 
1052 /**
1053  * svm_range_split_by_granularity - collect ranges within granularity boundary
1054  *
1055  * @p: the process with svms list
1056  * @mm: mm structure
1057  * @addr: the vm fault address in pages, to split the prange
1058  * @parent: parent range if prange is from child list
1059  * @prange: prange to split
1060  *
1061  * Trims @prange to be a single aligned block of prange->granularity if
1062  * possible. The head and tail are added to the child_list in @parent.
1063  *
1064  * Context: caller must hold mmap_read_lock and prange->lock
1065  *
1066  * Return:
1067  * 0 - OK, otherwise error code
1068  */
1069 int
1070 svm_range_split_by_granularity(struct kfd_process *p, struct mm_struct *mm,
1071 			       unsigned long addr, struct svm_range *parent,
1072 			       struct svm_range *prange)
1073 {
1074 	struct svm_range *head, *tail;
1075 	unsigned long start, last, size;
1076 	int r;
1077 
1078 	/* Align splited range start and size to granularity size, then a single
1079 	 * PTE will be used for whole range, this reduces the number of PTE
1080 	 * updated and the L1 TLB space used for translation.
1081 	 */
1082 	size = 1UL << prange->granularity;
1083 	start = ALIGN_DOWN(addr, size);
1084 	last = ALIGN(addr + 1, size) - 1;
1085 
1086 	pr_debug("svms 0x%p split [0x%lx 0x%lx] to [0x%lx 0x%lx] size 0x%lx\n",
1087 		 prange->svms, prange->start, prange->last, start, last, size);
1088 
1089 	if (start > prange->start) {
1090 		r = svm_range_split(prange, start, prange->last, &head);
1091 		if (r)
1092 			return r;
1093 		svm_range_add_child(parent, mm, head, SVM_OP_ADD_RANGE);
1094 	}
1095 
1096 	if (last < prange->last) {
1097 		r = svm_range_split(prange, prange->start, last, &tail);
1098 		if (r)
1099 			return r;
1100 		svm_range_add_child(parent, mm, tail, SVM_OP_ADD_RANGE);
1101 	}
1102 
1103 	/* xnack on, update mapping on GPUs with ACCESS_IN_PLACE */
1104 	if (p->xnack_enabled && prange->work_item.op == SVM_OP_ADD_RANGE) {
1105 		prange->work_item.op = SVM_OP_ADD_RANGE_AND_MAP;
1106 		pr_debug("change prange 0x%p [0x%lx 0x%lx] op %d\n",
1107 			 prange, prange->start, prange->last,
1108 			 SVM_OP_ADD_RANGE_AND_MAP);
1109 	}
1110 	return 0;
1111 }
1112 
1113 static uint64_t
1114 svm_range_get_pte_flags(struct amdgpu_device *adev, struct svm_range *prange,
1115 			int domain)
1116 {
1117 	struct amdgpu_device *bo_adev;
1118 	uint32_t flags = prange->flags;
1119 	uint32_t mapping_flags = 0;
1120 	uint64_t pte_flags;
1121 	bool snoop = (domain != SVM_RANGE_VRAM_DOMAIN);
1122 	bool coherent = flags & KFD_IOCTL_SVM_FLAG_COHERENT;
1123 
1124 	if (domain == SVM_RANGE_VRAM_DOMAIN)
1125 		bo_adev = amdgpu_ttm_adev(prange->svm_bo->bo->tbo.bdev);
1126 
1127 	switch (KFD_GC_VERSION(adev->kfd.dev)) {
1128 	case IP_VERSION(9, 4, 1):
1129 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1130 			if (bo_adev == adev) {
1131 				mapping_flags |= coherent ?
1132 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1133 			} else {
1134 				mapping_flags |= coherent ?
1135 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1136 				if (amdgpu_xgmi_same_hive(adev, bo_adev))
1137 					snoop = true;
1138 			}
1139 		} else {
1140 			mapping_flags |= coherent ?
1141 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1142 		}
1143 		break;
1144 	case IP_VERSION(9, 4, 2):
1145 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1146 			if (bo_adev == adev) {
1147 				mapping_flags |= coherent ?
1148 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1149 				if (adev->gmc.xgmi.connected_to_cpu)
1150 					snoop = true;
1151 			} else {
1152 				mapping_flags |= coherent ?
1153 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1154 				if (amdgpu_xgmi_same_hive(adev, bo_adev))
1155 					snoop = true;
1156 			}
1157 		} else {
1158 			mapping_flags |= coherent ?
1159 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1160 		}
1161 		break;
1162 	default:
1163 		mapping_flags |= coherent ?
1164 			AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1165 	}
1166 
1167 	mapping_flags |= AMDGPU_VM_PAGE_READABLE | AMDGPU_VM_PAGE_WRITEABLE;
1168 
1169 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_RO)
1170 		mapping_flags &= ~AMDGPU_VM_PAGE_WRITEABLE;
1171 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_EXEC)
1172 		mapping_flags |= AMDGPU_VM_PAGE_EXECUTABLE;
1173 
1174 	pte_flags = AMDGPU_PTE_VALID;
1175 	pte_flags |= (domain == SVM_RANGE_VRAM_DOMAIN) ? 0 : AMDGPU_PTE_SYSTEM;
1176 	pte_flags |= snoop ? AMDGPU_PTE_SNOOPED : 0;
1177 
1178 	pte_flags |= amdgpu_gem_va_map_flags(adev, mapping_flags);
1179 	return pte_flags;
1180 }
1181 
1182 static int
1183 svm_range_unmap_from_gpu(struct amdgpu_device *adev, struct amdgpu_vm *vm,
1184 			 uint64_t start, uint64_t last,
1185 			 struct dma_fence **fence)
1186 {
1187 	uint64_t init_pte_value = 0;
1188 
1189 	pr_debug("[0x%llx 0x%llx]\n", start, last);
1190 
1191 	return amdgpu_vm_update_range(adev, vm, false, true, true, NULL, start,
1192 				      last, init_pte_value, 0, 0, NULL, NULL,
1193 				      fence);
1194 }
1195 
1196 static int
1197 svm_range_unmap_from_gpus(struct svm_range *prange, unsigned long start,
1198 			  unsigned long last)
1199 {
1200 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1201 	struct kfd_process_device *pdd;
1202 	struct dma_fence *fence = NULL;
1203 	struct kfd_process *p;
1204 	uint32_t gpuidx;
1205 	int r = 0;
1206 
1207 	bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
1208 		  MAX_GPU_INSTANCE);
1209 	p = container_of(prange->svms, struct kfd_process, svms);
1210 
1211 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1212 		pr_debug("unmap from gpu idx 0x%x\n", gpuidx);
1213 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1214 		if (!pdd) {
1215 			pr_debug("failed to find device idx %d\n", gpuidx);
1216 			return -EINVAL;
1217 		}
1218 
1219 		r = svm_range_unmap_from_gpu(pdd->dev->adev,
1220 					     drm_priv_to_vm(pdd->drm_priv),
1221 					     start, last, &fence);
1222 		if (r)
1223 			break;
1224 
1225 		if (fence) {
1226 			r = dma_fence_wait(fence, false);
1227 			dma_fence_put(fence);
1228 			fence = NULL;
1229 			if (r)
1230 				break;
1231 		}
1232 		kfd_flush_tlb(pdd, TLB_FLUSH_HEAVYWEIGHT);
1233 	}
1234 
1235 	return r;
1236 }
1237 
1238 static int
1239 svm_range_map_to_gpu(struct kfd_process_device *pdd, struct svm_range *prange,
1240 		     unsigned long offset, unsigned long npages, bool readonly,
1241 		     dma_addr_t *dma_addr, struct amdgpu_device *bo_adev,
1242 		     struct dma_fence **fence)
1243 {
1244 	struct amdgpu_device *adev = pdd->dev->adev;
1245 	struct amdgpu_vm *vm = drm_priv_to_vm(pdd->drm_priv);
1246 	uint64_t pte_flags;
1247 	unsigned long last_start;
1248 	int last_domain;
1249 	int r = 0;
1250 	int64_t i, j;
1251 
1252 	last_start = prange->start + offset;
1253 
1254 	pr_debug("svms 0x%p [0x%lx 0x%lx] readonly %d\n", prange->svms,
1255 		 last_start, last_start + npages - 1, readonly);
1256 
1257 	for (i = offset; i < offset + npages; i++) {
1258 		last_domain = dma_addr[i] & SVM_RANGE_VRAM_DOMAIN;
1259 		dma_addr[i] &= ~SVM_RANGE_VRAM_DOMAIN;
1260 
1261 		/* Collect all pages in the same address range and memory domain
1262 		 * that can be mapped with a single call to update mapping.
1263 		 */
1264 		if (i < offset + npages - 1 &&
1265 		    last_domain == (dma_addr[i + 1] & SVM_RANGE_VRAM_DOMAIN))
1266 			continue;
1267 
1268 		pr_debug("Mapping range [0x%lx 0x%llx] on domain: %s\n",
1269 			 last_start, prange->start + i, last_domain ? "GPU" : "CPU");
1270 
1271 		pte_flags = svm_range_get_pte_flags(adev, prange, last_domain);
1272 		if (readonly)
1273 			pte_flags &= ~AMDGPU_PTE_WRITEABLE;
1274 
1275 		pr_debug("svms 0x%p map [0x%lx 0x%llx] vram %d PTE 0x%llx\n",
1276 			 prange->svms, last_start, prange->start + i,
1277 			 (last_domain == SVM_RANGE_VRAM_DOMAIN) ? 1 : 0,
1278 			 pte_flags);
1279 
1280 		r = amdgpu_vm_update_range(adev, vm, false, false, false, NULL,
1281 					   last_start, prange->start + i,
1282 					   pte_flags,
1283 					   last_start - prange->start,
1284 					   bo_adev ? bo_adev->vm_manager.vram_base_offset : 0,
1285 					   NULL, dma_addr, &vm->last_update);
1286 
1287 		for (j = last_start - prange->start; j <= i; j++)
1288 			dma_addr[j] |= last_domain;
1289 
1290 		if (r) {
1291 			pr_debug("failed %d to map to gpu 0x%lx\n", r, prange->start);
1292 			goto out;
1293 		}
1294 		last_start = prange->start + i + 1;
1295 	}
1296 
1297 	r = amdgpu_vm_update_pdes(adev, vm, false);
1298 	if (r) {
1299 		pr_debug("failed %d to update directories 0x%lx\n", r,
1300 			 prange->start);
1301 		goto out;
1302 	}
1303 
1304 	if (fence)
1305 		*fence = dma_fence_get(vm->last_update);
1306 
1307 out:
1308 	return r;
1309 }
1310 
1311 static int
1312 svm_range_map_to_gpus(struct svm_range *prange, unsigned long offset,
1313 		      unsigned long npages, bool readonly,
1314 		      unsigned long *bitmap, bool wait)
1315 {
1316 	struct kfd_process_device *pdd;
1317 	struct amdgpu_device *bo_adev;
1318 	struct kfd_process *p;
1319 	struct dma_fence *fence = NULL;
1320 	uint32_t gpuidx;
1321 	int r = 0;
1322 
1323 	if (prange->svm_bo && prange->ttm_res)
1324 		bo_adev = amdgpu_ttm_adev(prange->svm_bo->bo->tbo.bdev);
1325 	else
1326 		bo_adev = NULL;
1327 
1328 	p = container_of(prange->svms, struct kfd_process, svms);
1329 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1330 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
1331 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1332 		if (!pdd) {
1333 			pr_debug("failed to find device idx %d\n", gpuidx);
1334 			return -EINVAL;
1335 		}
1336 
1337 		pdd = kfd_bind_process_to_device(pdd->dev, p);
1338 		if (IS_ERR(pdd))
1339 			return -EINVAL;
1340 
1341 		if (bo_adev && pdd->dev->adev != bo_adev &&
1342 		    !amdgpu_xgmi_same_hive(pdd->dev->adev, bo_adev)) {
1343 			pr_debug("cannot map to device idx %d\n", gpuidx);
1344 			continue;
1345 		}
1346 
1347 		r = svm_range_map_to_gpu(pdd, prange, offset, npages, readonly,
1348 					 prange->dma_addr[gpuidx],
1349 					 bo_adev, wait ? &fence : NULL);
1350 		if (r)
1351 			break;
1352 
1353 		if (fence) {
1354 			r = dma_fence_wait(fence, false);
1355 			dma_fence_put(fence);
1356 			fence = NULL;
1357 			if (r) {
1358 				pr_debug("failed %d to dma fence wait\n", r);
1359 				break;
1360 			}
1361 		}
1362 
1363 		kfd_flush_tlb(pdd, TLB_FLUSH_LEGACY);
1364 	}
1365 
1366 	return r;
1367 }
1368 
1369 struct svm_validate_context {
1370 	struct kfd_process *process;
1371 	struct svm_range *prange;
1372 	bool intr;
1373 	unsigned long bitmap[MAX_GPU_INSTANCE];
1374 	struct ttm_validate_buffer tv[MAX_GPU_INSTANCE];
1375 	struct list_head validate_list;
1376 	struct ww_acquire_ctx ticket;
1377 };
1378 
1379 static int svm_range_reserve_bos(struct svm_validate_context *ctx)
1380 {
1381 	struct kfd_process_device *pdd;
1382 	struct amdgpu_vm *vm;
1383 	uint32_t gpuidx;
1384 	int r;
1385 
1386 	INIT_LIST_HEAD(&ctx->validate_list);
1387 	for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1388 		pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1389 		if (!pdd) {
1390 			pr_debug("failed to find device idx %d\n", gpuidx);
1391 			return -EINVAL;
1392 		}
1393 		vm = drm_priv_to_vm(pdd->drm_priv);
1394 
1395 		ctx->tv[gpuidx].bo = &vm->root.bo->tbo;
1396 		ctx->tv[gpuidx].num_shared = 4;
1397 		list_add(&ctx->tv[gpuidx].head, &ctx->validate_list);
1398 	}
1399 
1400 	r = ttm_eu_reserve_buffers(&ctx->ticket, &ctx->validate_list,
1401 				   ctx->intr, NULL);
1402 	if (r) {
1403 		pr_debug("failed %d to reserve bo\n", r);
1404 		return r;
1405 	}
1406 
1407 	for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1408 		pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1409 		if (!pdd) {
1410 			pr_debug("failed to find device idx %d\n", gpuidx);
1411 			r = -EINVAL;
1412 			goto unreserve_out;
1413 		}
1414 
1415 		r = amdgpu_vm_validate_pt_bos(pdd->dev->adev,
1416 					      drm_priv_to_vm(pdd->drm_priv),
1417 					      svm_range_bo_validate, NULL);
1418 		if (r) {
1419 			pr_debug("failed %d validate pt bos\n", r);
1420 			goto unreserve_out;
1421 		}
1422 	}
1423 
1424 	return 0;
1425 
1426 unreserve_out:
1427 	ttm_eu_backoff_reservation(&ctx->ticket, &ctx->validate_list);
1428 	return r;
1429 }
1430 
1431 static void svm_range_unreserve_bos(struct svm_validate_context *ctx)
1432 {
1433 	ttm_eu_backoff_reservation(&ctx->ticket, &ctx->validate_list);
1434 }
1435 
1436 static void *kfd_svm_page_owner(struct kfd_process *p, int32_t gpuidx)
1437 {
1438 	struct kfd_process_device *pdd;
1439 
1440 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1441 
1442 	return SVM_ADEV_PGMAP_OWNER(pdd->dev->adev);
1443 }
1444 
1445 /*
1446  * Validation+GPU mapping with concurrent invalidation (MMU notifiers)
1447  *
1448  * To prevent concurrent destruction or change of range attributes, the
1449  * svm_read_lock must be held. The caller must not hold the svm_write_lock
1450  * because that would block concurrent evictions and lead to deadlocks. To
1451  * serialize concurrent migrations or validations of the same range, the
1452  * prange->migrate_mutex must be held.
1453  *
1454  * For VRAM ranges, the SVM BO must be allocated and valid (protected by its
1455  * eviction fence.
1456  *
1457  * The following sequence ensures race-free validation and GPU mapping:
1458  *
1459  * 1. Reserve page table (and SVM BO if range is in VRAM)
1460  * 2. hmm_range_fault to get page addresses (if system memory)
1461  * 3. DMA-map pages (if system memory)
1462  * 4-a. Take notifier lock
1463  * 4-b. Check that pages still valid (mmu_interval_read_retry)
1464  * 4-c. Check that the range was not split or otherwise invalidated
1465  * 4-d. Update GPU page table
1466  * 4.e. Release notifier lock
1467  * 5. Release page table (and SVM BO) reservation
1468  */
1469 static int svm_range_validate_and_map(struct mm_struct *mm,
1470 				      struct svm_range *prange,
1471 				      int32_t gpuidx, bool intr, bool wait)
1472 {
1473 	struct svm_validate_context ctx;
1474 	unsigned long start, end, addr;
1475 	struct kfd_process *p;
1476 	void *owner;
1477 	int32_t idx;
1478 	int r = 0;
1479 
1480 	ctx.process = container_of(prange->svms, struct kfd_process, svms);
1481 	ctx.prange = prange;
1482 	ctx.intr = intr;
1483 
1484 	if (gpuidx < MAX_GPU_INSTANCE) {
1485 		bitmap_zero(ctx.bitmap, MAX_GPU_INSTANCE);
1486 		bitmap_set(ctx.bitmap, gpuidx, 1);
1487 	} else if (ctx.process->xnack_enabled) {
1488 		bitmap_copy(ctx.bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
1489 
1490 		/* If prefetch range to GPU, or GPU retry fault migrate range to
1491 		 * GPU, which has ACCESS attribute to the range, create mapping
1492 		 * on that GPU.
1493 		 */
1494 		if (prange->actual_loc) {
1495 			gpuidx = kfd_process_gpuidx_from_gpuid(ctx.process,
1496 							prange->actual_loc);
1497 			if (gpuidx < 0) {
1498 				WARN_ONCE(1, "failed get device by id 0x%x\n",
1499 					 prange->actual_loc);
1500 				return -EINVAL;
1501 			}
1502 			if (test_bit(gpuidx, prange->bitmap_access))
1503 				bitmap_set(ctx.bitmap, gpuidx, 1);
1504 		}
1505 	} else {
1506 		bitmap_or(ctx.bitmap, prange->bitmap_access,
1507 			  prange->bitmap_aip, MAX_GPU_INSTANCE);
1508 	}
1509 
1510 	if (bitmap_empty(ctx.bitmap, MAX_GPU_INSTANCE))
1511 		return 0;
1512 
1513 	if (prange->actual_loc && !prange->ttm_res) {
1514 		/* This should never happen. actual_loc gets set by
1515 		 * svm_migrate_ram_to_vram after allocating a BO.
1516 		 */
1517 		WARN_ONCE(1, "VRAM BO missing during validation\n");
1518 		return -EINVAL;
1519 	}
1520 
1521 	svm_range_reserve_bos(&ctx);
1522 
1523 	p = container_of(prange->svms, struct kfd_process, svms);
1524 	owner = kfd_svm_page_owner(p, find_first_bit(ctx.bitmap,
1525 						MAX_GPU_INSTANCE));
1526 	for_each_set_bit(idx, ctx.bitmap, MAX_GPU_INSTANCE) {
1527 		if (kfd_svm_page_owner(p, idx) != owner) {
1528 			owner = NULL;
1529 			break;
1530 		}
1531 	}
1532 
1533 	start = prange->start << PAGE_SHIFT;
1534 	end = (prange->last + 1) << PAGE_SHIFT;
1535 	for (addr = start; addr < end && !r; ) {
1536 		struct hmm_range *hmm_range;
1537 		struct vm_area_struct *vma;
1538 		unsigned long next;
1539 		unsigned long offset;
1540 		unsigned long npages;
1541 		bool readonly;
1542 
1543 		vma = find_vma(mm, addr);
1544 		if (!vma || addr < vma->vm_start) {
1545 			r = -EFAULT;
1546 			goto unreserve_out;
1547 		}
1548 		readonly = !(vma->vm_flags & VM_WRITE);
1549 
1550 		next = min(vma->vm_end, end);
1551 		npages = (next - addr) >> PAGE_SHIFT;
1552 		WRITE_ONCE(p->svms.faulting_task, current);
1553 		r = amdgpu_hmm_range_get_pages(&prange->notifier, mm, NULL,
1554 					       addr, npages, &hmm_range,
1555 					       readonly, true, owner);
1556 		WRITE_ONCE(p->svms.faulting_task, NULL);
1557 		if (r) {
1558 			pr_debug("failed %d to get svm range pages\n", r);
1559 			goto unreserve_out;
1560 		}
1561 
1562 		offset = (addr - start) >> PAGE_SHIFT;
1563 		r = svm_range_dma_map(prange, ctx.bitmap, offset, npages,
1564 				      hmm_range->hmm_pfns);
1565 		if (r) {
1566 			pr_debug("failed %d to dma map range\n", r);
1567 			goto unreserve_out;
1568 		}
1569 
1570 		svm_range_lock(prange);
1571 		if (amdgpu_hmm_range_get_pages_done(hmm_range)) {
1572 			pr_debug("hmm update the range, need validate again\n");
1573 			r = -EAGAIN;
1574 			goto unlock_out;
1575 		}
1576 		if (!list_empty(&prange->child_list)) {
1577 			pr_debug("range split by unmap in parallel, validate again\n");
1578 			r = -EAGAIN;
1579 			goto unlock_out;
1580 		}
1581 
1582 		r = svm_range_map_to_gpus(prange, offset, npages, readonly,
1583 					  ctx.bitmap, wait);
1584 
1585 unlock_out:
1586 		svm_range_unlock(prange);
1587 
1588 		addr = next;
1589 	}
1590 
1591 	if (addr == end)
1592 		prange->validated_once = true;
1593 
1594 unreserve_out:
1595 	svm_range_unreserve_bos(&ctx);
1596 
1597 	if (!r)
1598 		prange->validate_timestamp = ktime_to_us(ktime_get());
1599 
1600 	return r;
1601 }
1602 
1603 /**
1604  * svm_range_list_lock_and_flush_work - flush pending deferred work
1605  *
1606  * @svms: the svm range list
1607  * @mm: the mm structure
1608  *
1609  * Context: Returns with mmap write lock held, pending deferred work flushed
1610  *
1611  */
1612 void
1613 svm_range_list_lock_and_flush_work(struct svm_range_list *svms,
1614 				   struct mm_struct *mm)
1615 {
1616 retry_flush_work:
1617 	flush_work(&svms->deferred_list_work);
1618 	mmap_write_lock(mm);
1619 
1620 	if (list_empty(&svms->deferred_range_list))
1621 		return;
1622 	mmap_write_unlock(mm);
1623 	pr_debug("retry flush\n");
1624 	goto retry_flush_work;
1625 }
1626 
1627 static void svm_range_restore_work(struct work_struct *work)
1628 {
1629 	struct delayed_work *dwork = to_delayed_work(work);
1630 	struct amdkfd_process_info *process_info;
1631 	struct svm_range_list *svms;
1632 	struct svm_range *prange;
1633 	struct kfd_process *p;
1634 	struct mm_struct *mm;
1635 	int evicted_ranges;
1636 	int invalid;
1637 	int r;
1638 
1639 	svms = container_of(dwork, struct svm_range_list, restore_work);
1640 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1641 	if (!evicted_ranges)
1642 		return;
1643 
1644 	pr_debug("restore svm ranges\n");
1645 
1646 	p = container_of(svms, struct kfd_process, svms);
1647 	process_info = p->kgd_process_info;
1648 
1649 	/* Keep mm reference when svm_range_validate_and_map ranges */
1650 	mm = get_task_mm(p->lead_thread);
1651 	if (!mm) {
1652 		pr_debug("svms 0x%p process mm gone\n", svms);
1653 		return;
1654 	}
1655 
1656 	mutex_lock(&process_info->lock);
1657 	svm_range_list_lock_and_flush_work(svms, mm);
1658 	mutex_lock(&svms->lock);
1659 
1660 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1661 
1662 	list_for_each_entry(prange, &svms->list, list) {
1663 		invalid = atomic_read(&prange->invalid);
1664 		if (!invalid)
1665 			continue;
1666 
1667 		pr_debug("restoring svms 0x%p prange 0x%p [0x%lx %lx] inv %d\n",
1668 			 prange->svms, prange, prange->start, prange->last,
1669 			 invalid);
1670 
1671 		/*
1672 		 * If range is migrating, wait for migration is done.
1673 		 */
1674 		mutex_lock(&prange->migrate_mutex);
1675 
1676 		r = svm_range_validate_and_map(mm, prange, MAX_GPU_INSTANCE,
1677 					       false, true);
1678 		if (r)
1679 			pr_debug("failed %d to map 0x%lx to gpus\n", r,
1680 				 prange->start);
1681 
1682 		mutex_unlock(&prange->migrate_mutex);
1683 		if (r)
1684 			goto out_reschedule;
1685 
1686 		if (atomic_cmpxchg(&prange->invalid, invalid, 0) != invalid)
1687 			goto out_reschedule;
1688 	}
1689 
1690 	if (atomic_cmpxchg(&svms->evicted_ranges, evicted_ranges, 0) !=
1691 	    evicted_ranges)
1692 		goto out_reschedule;
1693 
1694 	evicted_ranges = 0;
1695 
1696 	r = kgd2kfd_resume_mm(mm);
1697 	if (r) {
1698 		/* No recovery from this failure. Probably the CP is
1699 		 * hanging. No point trying again.
1700 		 */
1701 		pr_debug("failed %d to resume KFD\n", r);
1702 	}
1703 
1704 	pr_debug("restore svm ranges successfully\n");
1705 
1706 out_reschedule:
1707 	mutex_unlock(&svms->lock);
1708 	mmap_write_unlock(mm);
1709 	mutex_unlock(&process_info->lock);
1710 	mmput(mm);
1711 
1712 	/* If validation failed, reschedule another attempt */
1713 	if (evicted_ranges) {
1714 		pr_debug("reschedule to restore svm range\n");
1715 		schedule_delayed_work(&svms->restore_work,
1716 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1717 	}
1718 }
1719 
1720 /**
1721  * svm_range_evict - evict svm range
1722  * @prange: svm range structure
1723  * @mm: current process mm_struct
1724  * @start: starting process queue number
1725  * @last: last process queue number
1726  *
1727  * Stop all queues of the process to ensure GPU doesn't access the memory, then
1728  * return to let CPU evict the buffer and proceed CPU pagetable update.
1729  *
1730  * Don't need use lock to sync cpu pagetable invalidation with GPU execution.
1731  * If invalidation happens while restore work is running, restore work will
1732  * restart to ensure to get the latest CPU pages mapping to GPU, then start
1733  * the queues.
1734  */
1735 static int
1736 svm_range_evict(struct svm_range *prange, struct mm_struct *mm,
1737 		unsigned long start, unsigned long last)
1738 {
1739 	struct svm_range_list *svms = prange->svms;
1740 	struct svm_range *pchild;
1741 	struct kfd_process *p;
1742 	int r = 0;
1743 
1744 	p = container_of(svms, struct kfd_process, svms);
1745 
1746 	pr_debug("invalidate svms 0x%p prange [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
1747 		 svms, prange->start, prange->last, start, last);
1748 
1749 	if (!p->xnack_enabled) {
1750 		int evicted_ranges;
1751 
1752 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1753 			mutex_lock_nested(&pchild->lock, 1);
1754 			if (pchild->start <= last && pchild->last >= start) {
1755 				pr_debug("increment pchild invalid [0x%lx 0x%lx]\n",
1756 					 pchild->start, pchild->last);
1757 				atomic_inc(&pchild->invalid);
1758 			}
1759 			mutex_unlock(&pchild->lock);
1760 		}
1761 
1762 		if (prange->start <= last && prange->last >= start)
1763 			atomic_inc(&prange->invalid);
1764 
1765 		evicted_ranges = atomic_inc_return(&svms->evicted_ranges);
1766 		if (evicted_ranges != 1)
1767 			return r;
1768 
1769 		pr_debug("evicting svms 0x%p range [0x%lx 0x%lx]\n",
1770 			 prange->svms, prange->start, prange->last);
1771 
1772 		/* First eviction, stop the queues */
1773 		r = kgd2kfd_quiesce_mm(mm);
1774 		if (r)
1775 			pr_debug("failed to quiesce KFD\n");
1776 
1777 		pr_debug("schedule to restore svm %p ranges\n", svms);
1778 		schedule_delayed_work(&svms->restore_work,
1779 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1780 	} else {
1781 		unsigned long s, l;
1782 
1783 		pr_debug("invalidate unmap svms 0x%p [0x%lx 0x%lx] from GPUs\n",
1784 			 prange->svms, start, last);
1785 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1786 			mutex_lock_nested(&pchild->lock, 1);
1787 			s = max(start, pchild->start);
1788 			l = min(last, pchild->last);
1789 			if (l >= s)
1790 				svm_range_unmap_from_gpus(pchild, s, l);
1791 			mutex_unlock(&pchild->lock);
1792 		}
1793 		s = max(start, prange->start);
1794 		l = min(last, prange->last);
1795 		if (l >= s)
1796 			svm_range_unmap_from_gpus(prange, s, l);
1797 	}
1798 
1799 	return r;
1800 }
1801 
1802 static struct svm_range *svm_range_clone(struct svm_range *old)
1803 {
1804 	struct svm_range *new;
1805 
1806 	new = svm_range_new(old->svms, old->start, old->last);
1807 	if (!new)
1808 		return NULL;
1809 
1810 	if (old->svm_bo) {
1811 		new->ttm_res = old->ttm_res;
1812 		new->offset = old->offset;
1813 		new->svm_bo = svm_range_bo_ref(old->svm_bo);
1814 		spin_lock(&new->svm_bo->list_lock);
1815 		list_add(&new->svm_bo_list, &new->svm_bo->range_list);
1816 		spin_unlock(&new->svm_bo->list_lock);
1817 	}
1818 	new->flags = old->flags;
1819 	new->preferred_loc = old->preferred_loc;
1820 	new->prefetch_loc = old->prefetch_loc;
1821 	new->actual_loc = old->actual_loc;
1822 	new->granularity = old->granularity;
1823 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
1824 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
1825 
1826 	return new;
1827 }
1828 
1829 /**
1830  * svm_range_add - add svm range and handle overlap
1831  * @p: the range add to this process svms
1832  * @start: page size aligned
1833  * @size: page size aligned
1834  * @nattr: number of attributes
1835  * @attrs: array of attributes
1836  * @update_list: output, the ranges need validate and update GPU mapping
1837  * @insert_list: output, the ranges need insert to svms
1838  * @remove_list: output, the ranges are replaced and need remove from svms
1839  *
1840  * Check if the virtual address range has overlap with any existing ranges,
1841  * split partly overlapping ranges and add new ranges in the gaps. All changes
1842  * should be applied to the range_list and interval tree transactionally. If
1843  * any range split or allocation fails, the entire update fails. Therefore any
1844  * existing overlapping svm_ranges are cloned and the original svm_ranges left
1845  * unchanged.
1846  *
1847  * If the transaction succeeds, the caller can update and insert clones and
1848  * new ranges, then free the originals.
1849  *
1850  * Otherwise the caller can free the clones and new ranges, while the old
1851  * svm_ranges remain unchanged.
1852  *
1853  * Context: Process context, caller must hold svms->lock
1854  *
1855  * Return:
1856  * 0 - OK, otherwise error code
1857  */
1858 static int
1859 svm_range_add(struct kfd_process *p, uint64_t start, uint64_t size,
1860 	      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
1861 	      struct list_head *update_list, struct list_head *insert_list,
1862 	      struct list_head *remove_list)
1863 {
1864 	unsigned long last = start + size - 1UL;
1865 	struct svm_range_list *svms = &p->svms;
1866 	struct interval_tree_node *node;
1867 	struct svm_range *prange;
1868 	struct svm_range *tmp;
1869 	int r = 0;
1870 
1871 	pr_debug("svms 0x%p [0x%llx 0x%lx]\n", &p->svms, start, last);
1872 
1873 	INIT_LIST_HEAD(update_list);
1874 	INIT_LIST_HEAD(insert_list);
1875 	INIT_LIST_HEAD(remove_list);
1876 
1877 	node = interval_tree_iter_first(&svms->objects, start, last);
1878 	while (node) {
1879 		struct interval_tree_node *next;
1880 		unsigned long next_start;
1881 
1882 		pr_debug("found overlap node [0x%lx 0x%lx]\n", node->start,
1883 			 node->last);
1884 
1885 		prange = container_of(node, struct svm_range, it_node);
1886 		next = interval_tree_iter_next(node, start, last);
1887 		next_start = min(node->last, last) + 1;
1888 
1889 		if (svm_range_is_same_attrs(p, prange, nattr, attrs)) {
1890 			/* nothing to do */
1891 		} else if (node->start < start || node->last > last) {
1892 			/* node intersects the update range and its attributes
1893 			 * will change. Clone and split it, apply updates only
1894 			 * to the overlapping part
1895 			 */
1896 			struct svm_range *old = prange;
1897 
1898 			prange = svm_range_clone(old);
1899 			if (!prange) {
1900 				r = -ENOMEM;
1901 				goto out;
1902 			}
1903 
1904 			list_add(&old->update_list, remove_list);
1905 			list_add(&prange->list, insert_list);
1906 			list_add(&prange->update_list, update_list);
1907 
1908 			if (node->start < start) {
1909 				pr_debug("change old range start\n");
1910 				r = svm_range_split_head(prange, start,
1911 							 insert_list);
1912 				if (r)
1913 					goto out;
1914 			}
1915 			if (node->last > last) {
1916 				pr_debug("change old range last\n");
1917 				r = svm_range_split_tail(prange, last,
1918 							 insert_list);
1919 				if (r)
1920 					goto out;
1921 			}
1922 		} else {
1923 			/* The node is contained within start..last,
1924 			 * just update it
1925 			 */
1926 			list_add(&prange->update_list, update_list);
1927 		}
1928 
1929 		/* insert a new node if needed */
1930 		if (node->start > start) {
1931 			prange = svm_range_new(svms, start, node->start - 1);
1932 			if (!prange) {
1933 				r = -ENOMEM;
1934 				goto out;
1935 			}
1936 
1937 			list_add(&prange->list, insert_list);
1938 			list_add(&prange->update_list, update_list);
1939 		}
1940 
1941 		node = next;
1942 		start = next_start;
1943 	}
1944 
1945 	/* add a final range at the end if needed */
1946 	if (start <= last) {
1947 		prange = svm_range_new(svms, start, last);
1948 		if (!prange) {
1949 			r = -ENOMEM;
1950 			goto out;
1951 		}
1952 		list_add(&prange->list, insert_list);
1953 		list_add(&prange->update_list, update_list);
1954 	}
1955 
1956 out:
1957 	if (r)
1958 		list_for_each_entry_safe(prange, tmp, insert_list, list)
1959 			svm_range_free(prange);
1960 
1961 	return r;
1962 }
1963 
1964 static void
1965 svm_range_update_notifier_and_interval_tree(struct mm_struct *mm,
1966 					    struct svm_range *prange)
1967 {
1968 	unsigned long start;
1969 	unsigned long last;
1970 
1971 	start = prange->notifier.interval_tree.start >> PAGE_SHIFT;
1972 	last = prange->notifier.interval_tree.last >> PAGE_SHIFT;
1973 
1974 	if (prange->start == start && prange->last == last)
1975 		return;
1976 
1977 	pr_debug("up notifier 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
1978 		  prange->svms, prange, start, last, prange->start,
1979 		  prange->last);
1980 
1981 	if (start != 0 && last != 0) {
1982 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
1983 		svm_range_remove_notifier(prange);
1984 	}
1985 	prange->it_node.start = prange->start;
1986 	prange->it_node.last = prange->last;
1987 
1988 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
1989 	svm_range_add_notifier_locked(mm, prange);
1990 }
1991 
1992 static void
1993 svm_range_handle_list_op(struct svm_range_list *svms, struct svm_range *prange,
1994 			 struct mm_struct *mm)
1995 {
1996 	switch (prange->work_item.op) {
1997 	case SVM_OP_NULL:
1998 		pr_debug("NULL OP 0x%p prange 0x%p [0x%lx 0x%lx]\n",
1999 			 svms, prange, prange->start, prange->last);
2000 		break;
2001 	case SVM_OP_UNMAP_RANGE:
2002 		pr_debug("remove 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2003 			 svms, prange, prange->start, prange->last);
2004 		svm_range_unlink(prange);
2005 		svm_range_remove_notifier(prange);
2006 		svm_range_free(prange);
2007 		break;
2008 	case SVM_OP_UPDATE_RANGE_NOTIFIER:
2009 		pr_debug("update notifier 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2010 			 svms, prange, prange->start, prange->last);
2011 		svm_range_update_notifier_and_interval_tree(mm, prange);
2012 		break;
2013 	case SVM_OP_UPDATE_RANGE_NOTIFIER_AND_MAP:
2014 		pr_debug("update and map 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2015 			 svms, prange, prange->start, prange->last);
2016 		svm_range_update_notifier_and_interval_tree(mm, prange);
2017 		/* TODO: implement deferred validation and mapping */
2018 		break;
2019 	case SVM_OP_ADD_RANGE:
2020 		pr_debug("add 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms, prange,
2021 			 prange->start, prange->last);
2022 		svm_range_add_to_svms(prange);
2023 		svm_range_add_notifier_locked(mm, prange);
2024 		break;
2025 	case SVM_OP_ADD_RANGE_AND_MAP:
2026 		pr_debug("add and map 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms,
2027 			 prange, prange->start, prange->last);
2028 		svm_range_add_to_svms(prange);
2029 		svm_range_add_notifier_locked(mm, prange);
2030 		/* TODO: implement deferred validation and mapping */
2031 		break;
2032 	default:
2033 		WARN_ONCE(1, "Unknown prange 0x%p work op %d\n", prange,
2034 			 prange->work_item.op);
2035 	}
2036 }
2037 
2038 static void svm_range_drain_retry_fault(struct svm_range_list *svms)
2039 {
2040 	struct kfd_process_device *pdd;
2041 	struct kfd_process *p;
2042 	int drain;
2043 	uint32_t i;
2044 
2045 	p = container_of(svms, struct kfd_process, svms);
2046 
2047 restart:
2048 	drain = atomic_read(&svms->drain_pagefaults);
2049 	if (!drain)
2050 		return;
2051 
2052 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2053 		pdd = p->pdds[i];
2054 		if (!pdd)
2055 			continue;
2056 
2057 		pr_debug("drain retry fault gpu %d svms %p\n", i, svms);
2058 
2059 		amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2060 						     &pdd->dev->adev->irq.ih1);
2061 		pr_debug("drain retry fault gpu %d svms 0x%p done\n", i, svms);
2062 	}
2063 	if (atomic_cmpxchg(&svms->drain_pagefaults, drain, 0) != drain)
2064 		goto restart;
2065 }
2066 
2067 static void svm_range_deferred_list_work(struct work_struct *work)
2068 {
2069 	struct svm_range_list *svms;
2070 	struct svm_range *prange;
2071 	struct mm_struct *mm;
2072 
2073 	svms = container_of(work, struct svm_range_list, deferred_list_work);
2074 	pr_debug("enter svms 0x%p\n", svms);
2075 
2076 	spin_lock(&svms->deferred_list_lock);
2077 	while (!list_empty(&svms->deferred_range_list)) {
2078 		prange = list_first_entry(&svms->deferred_range_list,
2079 					  struct svm_range, deferred_list);
2080 		spin_unlock(&svms->deferred_list_lock);
2081 
2082 		pr_debug("prange 0x%p [0x%lx 0x%lx] op %d\n", prange,
2083 			 prange->start, prange->last, prange->work_item.op);
2084 
2085 		mm = prange->work_item.mm;
2086 retry:
2087 		mmap_write_lock(mm);
2088 
2089 		/* Checking for the need to drain retry faults must be inside
2090 		 * mmap write lock to serialize with munmap notifiers.
2091 		 */
2092 		if (unlikely(atomic_read(&svms->drain_pagefaults))) {
2093 			mmap_write_unlock(mm);
2094 			svm_range_drain_retry_fault(svms);
2095 			goto retry;
2096 		}
2097 
2098 		/* Remove from deferred_list must be inside mmap write lock, for
2099 		 * two race cases:
2100 		 * 1. unmap_from_cpu may change work_item.op and add the range
2101 		 *    to deferred_list again, cause use after free bug.
2102 		 * 2. svm_range_list_lock_and_flush_work may hold mmap write
2103 		 *    lock and continue because deferred_list is empty, but
2104 		 *    deferred_list work is actually waiting for mmap lock.
2105 		 */
2106 		spin_lock(&svms->deferred_list_lock);
2107 		list_del_init(&prange->deferred_list);
2108 		spin_unlock(&svms->deferred_list_lock);
2109 
2110 		mutex_lock(&svms->lock);
2111 		mutex_lock(&prange->migrate_mutex);
2112 		while (!list_empty(&prange->child_list)) {
2113 			struct svm_range *pchild;
2114 
2115 			pchild = list_first_entry(&prange->child_list,
2116 						struct svm_range, child_list);
2117 			pr_debug("child prange 0x%p op %d\n", pchild,
2118 				 pchild->work_item.op);
2119 			list_del_init(&pchild->child_list);
2120 			svm_range_handle_list_op(svms, pchild, mm);
2121 		}
2122 		mutex_unlock(&prange->migrate_mutex);
2123 
2124 		svm_range_handle_list_op(svms, prange, mm);
2125 		mutex_unlock(&svms->lock);
2126 		mmap_write_unlock(mm);
2127 
2128 		/* Pairs with mmget in svm_range_add_list_work */
2129 		mmput(mm);
2130 
2131 		spin_lock(&svms->deferred_list_lock);
2132 	}
2133 	spin_unlock(&svms->deferred_list_lock);
2134 	pr_debug("exit svms 0x%p\n", svms);
2135 }
2136 
2137 void
2138 svm_range_add_list_work(struct svm_range_list *svms, struct svm_range *prange,
2139 			struct mm_struct *mm, enum svm_work_list_ops op)
2140 {
2141 	spin_lock(&svms->deferred_list_lock);
2142 	/* if prange is on the deferred list */
2143 	if (!list_empty(&prange->deferred_list)) {
2144 		pr_debug("update exist prange 0x%p work op %d\n", prange, op);
2145 		WARN_ONCE(prange->work_item.mm != mm, "unmatch mm\n");
2146 		if (op != SVM_OP_NULL &&
2147 		    prange->work_item.op != SVM_OP_UNMAP_RANGE)
2148 			prange->work_item.op = op;
2149 	} else {
2150 		prange->work_item.op = op;
2151 
2152 		/* Pairs with mmput in deferred_list_work */
2153 		mmget(mm);
2154 		prange->work_item.mm = mm;
2155 		list_add_tail(&prange->deferred_list,
2156 			      &prange->svms->deferred_range_list);
2157 		pr_debug("add prange 0x%p [0x%lx 0x%lx] to work list op %d\n",
2158 			 prange, prange->start, prange->last, op);
2159 	}
2160 	spin_unlock(&svms->deferred_list_lock);
2161 }
2162 
2163 void schedule_deferred_list_work(struct svm_range_list *svms)
2164 {
2165 	spin_lock(&svms->deferred_list_lock);
2166 	if (!list_empty(&svms->deferred_range_list))
2167 		schedule_work(&svms->deferred_list_work);
2168 	spin_unlock(&svms->deferred_list_lock);
2169 }
2170 
2171 static void
2172 svm_range_unmap_split(struct mm_struct *mm, struct svm_range *parent,
2173 		      struct svm_range *prange, unsigned long start,
2174 		      unsigned long last)
2175 {
2176 	struct svm_range *head;
2177 	struct svm_range *tail;
2178 
2179 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2180 		pr_debug("prange 0x%p [0x%lx 0x%lx] is already freed\n", prange,
2181 			 prange->start, prange->last);
2182 		return;
2183 	}
2184 	if (start > prange->last || last < prange->start)
2185 		return;
2186 
2187 	head = tail = prange;
2188 	if (start > prange->start)
2189 		svm_range_split(prange, prange->start, start - 1, &tail);
2190 	if (last < tail->last)
2191 		svm_range_split(tail, last + 1, tail->last, &head);
2192 
2193 	if (head != prange && tail != prange) {
2194 		svm_range_add_child(parent, mm, head, SVM_OP_UNMAP_RANGE);
2195 		svm_range_add_child(parent, mm, tail, SVM_OP_ADD_RANGE);
2196 	} else if (tail != prange) {
2197 		svm_range_add_child(parent, mm, tail, SVM_OP_UNMAP_RANGE);
2198 	} else if (head != prange) {
2199 		svm_range_add_child(parent, mm, head, SVM_OP_UNMAP_RANGE);
2200 	} else if (parent != prange) {
2201 		prange->work_item.op = SVM_OP_UNMAP_RANGE;
2202 	}
2203 }
2204 
2205 static void
2206 svm_range_unmap_from_cpu(struct mm_struct *mm, struct svm_range *prange,
2207 			 unsigned long start, unsigned long last)
2208 {
2209 	struct svm_range_list *svms;
2210 	struct svm_range *pchild;
2211 	struct kfd_process *p;
2212 	unsigned long s, l;
2213 	bool unmap_parent;
2214 
2215 	p = kfd_lookup_process_by_mm(mm);
2216 	if (!p)
2217 		return;
2218 	svms = &p->svms;
2219 
2220 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n", svms,
2221 		 prange, prange->start, prange->last, start, last);
2222 
2223 	/* Make sure pending page faults are drained in the deferred worker
2224 	 * before the range is freed to avoid straggler interrupts on
2225 	 * unmapped memory causing "phantom faults".
2226 	 */
2227 	atomic_inc(&svms->drain_pagefaults);
2228 
2229 	unmap_parent = start <= prange->start && last >= prange->last;
2230 
2231 	list_for_each_entry(pchild, &prange->child_list, child_list) {
2232 		mutex_lock_nested(&pchild->lock, 1);
2233 		s = max(start, pchild->start);
2234 		l = min(last, pchild->last);
2235 		if (l >= s)
2236 			svm_range_unmap_from_gpus(pchild, s, l);
2237 		svm_range_unmap_split(mm, prange, pchild, start, last);
2238 		mutex_unlock(&pchild->lock);
2239 	}
2240 	s = max(start, prange->start);
2241 	l = min(last, prange->last);
2242 	if (l >= s)
2243 		svm_range_unmap_from_gpus(prange, s, l);
2244 	svm_range_unmap_split(mm, prange, prange, start, last);
2245 
2246 	if (unmap_parent)
2247 		svm_range_add_list_work(svms, prange, mm, SVM_OP_UNMAP_RANGE);
2248 	else
2249 		svm_range_add_list_work(svms, prange, mm,
2250 					SVM_OP_UPDATE_RANGE_NOTIFIER);
2251 	schedule_deferred_list_work(svms);
2252 
2253 	kfd_unref_process(p);
2254 }
2255 
2256 /**
2257  * svm_range_cpu_invalidate_pagetables - interval notifier callback
2258  * @mni: mmu_interval_notifier struct
2259  * @range: mmu_notifier_range struct
2260  * @cur_seq: value to pass to mmu_interval_set_seq()
2261  *
2262  * If event is MMU_NOTIFY_UNMAP, this is from CPU unmap range, otherwise, it
2263  * is from migration, or CPU page invalidation callback.
2264  *
2265  * For unmap event, unmap range from GPUs, remove prange from svms in a delayed
2266  * work thread, and split prange if only part of prange is unmapped.
2267  *
2268  * For invalidation event, if GPU retry fault is not enabled, evict the queues,
2269  * then schedule svm_range_restore_work to update GPU mapping and resume queues.
2270  * If GPU retry fault is enabled, unmap the svm range from GPU, retry fault will
2271  * update GPU mapping to recover.
2272  *
2273  * Context: mmap lock, notifier_invalidate_start lock are held
2274  *          for invalidate event, prange lock is held if this is from migration
2275  */
2276 static bool
2277 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
2278 				    const struct mmu_notifier_range *range,
2279 				    unsigned long cur_seq)
2280 {
2281 	struct svm_range *prange;
2282 	unsigned long start;
2283 	unsigned long last;
2284 
2285 	if (range->event == MMU_NOTIFY_RELEASE)
2286 		return true;
2287 
2288 	start = mni->interval_tree.start;
2289 	last = mni->interval_tree.last;
2290 	start = max(start, range->start) >> PAGE_SHIFT;
2291 	last = min(last, range->end - 1) >> PAGE_SHIFT;
2292 	pr_debug("[0x%lx 0x%lx] range[0x%lx 0x%lx] notifier[0x%lx 0x%lx] %d\n",
2293 		 start, last, range->start >> PAGE_SHIFT,
2294 		 (range->end - 1) >> PAGE_SHIFT,
2295 		 mni->interval_tree.start >> PAGE_SHIFT,
2296 		 mni->interval_tree.last >> PAGE_SHIFT, range->event);
2297 
2298 	prange = container_of(mni, struct svm_range, notifier);
2299 
2300 	svm_range_lock(prange);
2301 	mmu_interval_set_seq(mni, cur_seq);
2302 
2303 	switch (range->event) {
2304 	case MMU_NOTIFY_UNMAP:
2305 		svm_range_unmap_from_cpu(mni->mm, prange, start, last);
2306 		break;
2307 	default:
2308 		svm_range_evict(prange, mni->mm, start, last);
2309 		break;
2310 	}
2311 
2312 	svm_range_unlock(prange);
2313 
2314 	return true;
2315 }
2316 
2317 /**
2318  * svm_range_from_addr - find svm range from fault address
2319  * @svms: svm range list header
2320  * @addr: address to search range interval tree, in pages
2321  * @parent: parent range if range is on child list
2322  *
2323  * Context: The caller must hold svms->lock
2324  *
2325  * Return: the svm_range found or NULL
2326  */
2327 struct svm_range *
2328 svm_range_from_addr(struct svm_range_list *svms, unsigned long addr,
2329 		    struct svm_range **parent)
2330 {
2331 	struct interval_tree_node *node;
2332 	struct svm_range *prange;
2333 	struct svm_range *pchild;
2334 
2335 	node = interval_tree_iter_first(&svms->objects, addr, addr);
2336 	if (!node)
2337 		return NULL;
2338 
2339 	prange = container_of(node, struct svm_range, it_node);
2340 	pr_debug("address 0x%lx prange [0x%lx 0x%lx] node [0x%lx 0x%lx]\n",
2341 		 addr, prange->start, prange->last, node->start, node->last);
2342 
2343 	if (addr >= prange->start && addr <= prange->last) {
2344 		if (parent)
2345 			*parent = prange;
2346 		return prange;
2347 	}
2348 	list_for_each_entry(pchild, &prange->child_list, child_list)
2349 		if (addr >= pchild->start && addr <= pchild->last) {
2350 			pr_debug("found address 0x%lx pchild [0x%lx 0x%lx]\n",
2351 				 addr, pchild->start, pchild->last);
2352 			if (parent)
2353 				*parent = prange;
2354 			return pchild;
2355 		}
2356 
2357 	return NULL;
2358 }
2359 
2360 /* svm_range_best_restore_location - decide the best fault restore location
2361  * @prange: svm range structure
2362  * @adev: the GPU on which vm fault happened
2363  *
2364  * This is only called when xnack is on, to decide the best location to restore
2365  * the range mapping after GPU vm fault. Caller uses the best location to do
2366  * migration if actual loc is not best location, then update GPU page table
2367  * mapping to the best location.
2368  *
2369  * If the preferred loc is accessible by faulting GPU, use preferred loc.
2370  * If vm fault gpu idx is on range ACCESSIBLE bitmap, best_loc is vm fault gpu
2371  * If vm fault gpu idx is on range ACCESSIBLE_IN_PLACE bitmap, then
2372  *    if range actual loc is cpu, best_loc is cpu
2373  *    if vm fault gpu is on xgmi same hive of range actual loc gpu, best_loc is
2374  *    range actual loc.
2375  * Otherwise, GPU no access, best_loc is -1.
2376  *
2377  * Return:
2378  * -1 means vm fault GPU no access
2379  * 0 for CPU or GPU id
2380  */
2381 static int32_t
2382 svm_range_best_restore_location(struct svm_range *prange,
2383 				struct amdgpu_device *adev,
2384 				int32_t *gpuidx)
2385 {
2386 	struct amdgpu_device *bo_adev, *preferred_adev;
2387 	struct kfd_process *p;
2388 	uint32_t gpuid;
2389 	int r;
2390 
2391 	p = container_of(prange->svms, struct kfd_process, svms);
2392 
2393 	r = kfd_process_gpuid_from_adev(p, adev, &gpuid, gpuidx);
2394 	if (r < 0) {
2395 		pr_debug("failed to get gpuid from kgd\n");
2396 		return -1;
2397 	}
2398 
2399 	if (prange->preferred_loc == gpuid ||
2400 	    prange->preferred_loc == KFD_IOCTL_SVM_LOCATION_SYSMEM) {
2401 		return prange->preferred_loc;
2402 	} else if (prange->preferred_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
2403 		preferred_adev = svm_range_get_adev_by_id(prange,
2404 							prange->preferred_loc);
2405 		if (amdgpu_xgmi_same_hive(adev, preferred_adev))
2406 			return prange->preferred_loc;
2407 		/* fall through */
2408 	}
2409 
2410 	if (test_bit(*gpuidx, prange->bitmap_access))
2411 		return gpuid;
2412 
2413 	if (test_bit(*gpuidx, prange->bitmap_aip)) {
2414 		if (!prange->actual_loc)
2415 			return 0;
2416 
2417 		bo_adev = svm_range_get_adev_by_id(prange, prange->actual_loc);
2418 		if (amdgpu_xgmi_same_hive(adev, bo_adev))
2419 			return prange->actual_loc;
2420 		else
2421 			return 0;
2422 	}
2423 
2424 	return -1;
2425 }
2426 
2427 static int
2428 svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
2429 			       unsigned long *start, unsigned long *last,
2430 			       bool *is_heap_stack)
2431 {
2432 	struct vm_area_struct *vma;
2433 	struct interval_tree_node *node;
2434 	unsigned long start_limit, end_limit;
2435 
2436 	vma = find_vma(p->mm, addr << PAGE_SHIFT);
2437 	if (!vma || (addr << PAGE_SHIFT) < vma->vm_start) {
2438 		pr_debug("VMA does not exist in address [0x%llx]\n", addr);
2439 		return -EFAULT;
2440 	}
2441 
2442 	*is_heap_stack = (vma->vm_start <= vma->vm_mm->brk &&
2443 			  vma->vm_end >= vma->vm_mm->start_brk) ||
2444 			 (vma->vm_start <= vma->vm_mm->start_stack &&
2445 			  vma->vm_end >= vma->vm_mm->start_stack);
2446 
2447 	start_limit = max(vma->vm_start >> PAGE_SHIFT,
2448 		      (unsigned long)ALIGN_DOWN(addr, 2UL << 8));
2449 	end_limit = min(vma->vm_end >> PAGE_SHIFT,
2450 		    (unsigned long)ALIGN(addr + 1, 2UL << 8));
2451 	/* First range that starts after the fault address */
2452 	node = interval_tree_iter_first(&p->svms.objects, addr + 1, ULONG_MAX);
2453 	if (node) {
2454 		end_limit = min(end_limit, node->start);
2455 		/* Last range that ends before the fault address */
2456 		node = container_of(rb_prev(&node->rb),
2457 				    struct interval_tree_node, rb);
2458 	} else {
2459 		/* Last range must end before addr because
2460 		 * there was no range after addr
2461 		 */
2462 		node = container_of(rb_last(&p->svms.objects.rb_root),
2463 				    struct interval_tree_node, rb);
2464 	}
2465 	if (node) {
2466 		if (node->last >= addr) {
2467 			WARN(1, "Overlap with prev node and page fault addr\n");
2468 			return -EFAULT;
2469 		}
2470 		start_limit = max(start_limit, node->last + 1);
2471 	}
2472 
2473 	*start = start_limit;
2474 	*last = end_limit - 1;
2475 
2476 	pr_debug("vma [0x%lx 0x%lx] range [0x%lx 0x%lx] is_heap_stack %d\n",
2477 		 vma->vm_start >> PAGE_SHIFT, vma->vm_end >> PAGE_SHIFT,
2478 		 *start, *last, *is_heap_stack);
2479 
2480 	return 0;
2481 }
2482 
2483 static int
2484 svm_range_check_vm_userptr(struct kfd_process *p, uint64_t start, uint64_t last,
2485 			   uint64_t *bo_s, uint64_t *bo_l)
2486 {
2487 	struct amdgpu_bo_va_mapping *mapping;
2488 	struct interval_tree_node *node;
2489 	struct amdgpu_bo *bo = NULL;
2490 	unsigned long userptr;
2491 	uint32_t i;
2492 	int r;
2493 
2494 	for (i = 0; i < p->n_pdds; i++) {
2495 		struct amdgpu_vm *vm;
2496 
2497 		if (!p->pdds[i]->drm_priv)
2498 			continue;
2499 
2500 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
2501 		r = amdgpu_bo_reserve(vm->root.bo, false);
2502 		if (r)
2503 			return r;
2504 
2505 		/* Check userptr by searching entire vm->va interval tree */
2506 		node = interval_tree_iter_first(&vm->va, 0, ~0ULL);
2507 		while (node) {
2508 			mapping = container_of((struct rb_node *)node,
2509 					       struct amdgpu_bo_va_mapping, rb);
2510 			bo = mapping->bo_va->base.bo;
2511 
2512 			if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm,
2513 							 start << PAGE_SHIFT,
2514 							 last << PAGE_SHIFT,
2515 							 &userptr)) {
2516 				node = interval_tree_iter_next(node, 0, ~0ULL);
2517 				continue;
2518 			}
2519 
2520 			pr_debug("[0x%llx 0x%llx] already userptr mapped\n",
2521 				 start, last);
2522 			if (bo_s && bo_l) {
2523 				*bo_s = userptr >> PAGE_SHIFT;
2524 				*bo_l = *bo_s + bo->tbo.ttm->num_pages - 1;
2525 			}
2526 			amdgpu_bo_unreserve(vm->root.bo);
2527 			return -EADDRINUSE;
2528 		}
2529 		amdgpu_bo_unreserve(vm->root.bo);
2530 	}
2531 	return 0;
2532 }
2533 
2534 static struct
2535 svm_range *svm_range_create_unregistered_range(struct amdgpu_device *adev,
2536 						struct kfd_process *p,
2537 						struct mm_struct *mm,
2538 						int64_t addr)
2539 {
2540 	struct svm_range *prange = NULL;
2541 	unsigned long start, last;
2542 	uint32_t gpuid, gpuidx;
2543 	bool is_heap_stack;
2544 	uint64_t bo_s = 0;
2545 	uint64_t bo_l = 0;
2546 	int r;
2547 
2548 	if (svm_range_get_range_boundaries(p, addr, &start, &last,
2549 					   &is_heap_stack))
2550 		return NULL;
2551 
2552 	r = svm_range_check_vm(p, start, last, &bo_s, &bo_l);
2553 	if (r != -EADDRINUSE)
2554 		r = svm_range_check_vm_userptr(p, start, last, &bo_s, &bo_l);
2555 
2556 	if (r == -EADDRINUSE) {
2557 		if (addr >= bo_s && addr <= bo_l)
2558 			return NULL;
2559 
2560 		/* Create one page svm range if 2MB range overlapping */
2561 		start = addr;
2562 		last = addr;
2563 	}
2564 
2565 	prange = svm_range_new(&p->svms, start, last);
2566 	if (!prange) {
2567 		pr_debug("Failed to create prange in address [0x%llx]\n", addr);
2568 		return NULL;
2569 	}
2570 	if (kfd_process_gpuid_from_adev(p, adev, &gpuid, &gpuidx)) {
2571 		pr_debug("failed to get gpuid from kgd\n");
2572 		svm_range_free(prange);
2573 		return NULL;
2574 	}
2575 
2576 	if (is_heap_stack)
2577 		prange->preferred_loc = KFD_IOCTL_SVM_LOCATION_SYSMEM;
2578 
2579 	svm_range_add_to_svms(prange);
2580 	svm_range_add_notifier_locked(mm, prange);
2581 
2582 	return prange;
2583 }
2584 
2585 /* svm_range_skip_recover - decide if prange can be recovered
2586  * @prange: svm range structure
2587  *
2588  * GPU vm retry fault handle skip recover the range for cases:
2589  * 1. prange is on deferred list to be removed after unmap, it is stale fault,
2590  *    deferred list work will drain the stale fault before free the prange.
2591  * 2. prange is on deferred list to add interval notifier after split, or
2592  * 3. prange is child range, it is split from parent prange, recover later
2593  *    after interval notifier is added.
2594  *
2595  * Return: true to skip recover, false to recover
2596  */
2597 static bool svm_range_skip_recover(struct svm_range *prange)
2598 {
2599 	struct svm_range_list *svms = prange->svms;
2600 
2601 	spin_lock(&svms->deferred_list_lock);
2602 	if (list_empty(&prange->deferred_list) &&
2603 	    list_empty(&prange->child_list)) {
2604 		spin_unlock(&svms->deferred_list_lock);
2605 		return false;
2606 	}
2607 	spin_unlock(&svms->deferred_list_lock);
2608 
2609 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2610 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] unmapped\n",
2611 			 svms, prange, prange->start, prange->last);
2612 		return true;
2613 	}
2614 	if (prange->work_item.op == SVM_OP_ADD_RANGE_AND_MAP ||
2615 	    prange->work_item.op == SVM_OP_ADD_RANGE) {
2616 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] not added yet\n",
2617 			 svms, prange, prange->start, prange->last);
2618 		return true;
2619 	}
2620 	return false;
2621 }
2622 
2623 static void
2624 svm_range_count_fault(struct amdgpu_device *adev, struct kfd_process *p,
2625 		      int32_t gpuidx)
2626 {
2627 	struct kfd_process_device *pdd;
2628 
2629 	/* fault is on different page of same range
2630 	 * or fault is skipped to recover later
2631 	 * or fault is on invalid virtual address
2632 	 */
2633 	if (gpuidx == MAX_GPU_INSTANCE) {
2634 		uint32_t gpuid;
2635 		int r;
2636 
2637 		r = kfd_process_gpuid_from_adev(p, adev, &gpuid, &gpuidx);
2638 		if (r < 0)
2639 			return;
2640 	}
2641 
2642 	/* fault is recovered
2643 	 * or fault cannot recover because GPU no access on the range
2644 	 */
2645 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
2646 	if (pdd)
2647 		WRITE_ONCE(pdd->faults, pdd->faults + 1);
2648 }
2649 
2650 static bool
2651 svm_fault_allowed(struct vm_area_struct *vma, bool write_fault)
2652 {
2653 	unsigned long requested = VM_READ;
2654 
2655 	if (write_fault)
2656 		requested |= VM_WRITE;
2657 
2658 	pr_debug("requested 0x%lx, vma permission flags 0x%lx\n", requested,
2659 		vma->vm_flags);
2660 	return (vma->vm_flags & requested) == requested;
2661 }
2662 
2663 int
2664 svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
2665 			uint64_t addr, bool write_fault)
2666 {
2667 	struct mm_struct *mm = NULL;
2668 	struct svm_range_list *svms;
2669 	struct svm_range *prange;
2670 	struct kfd_process *p;
2671 	uint64_t timestamp;
2672 	int32_t best_loc;
2673 	int32_t gpuidx = MAX_GPU_INSTANCE;
2674 	bool write_locked = false;
2675 	struct vm_area_struct *vma;
2676 	int r = 0;
2677 
2678 	if (!KFD_IS_SVM_API_SUPPORTED(adev->kfd.dev)) {
2679 		pr_debug("device does not support SVM\n");
2680 		return -EFAULT;
2681 	}
2682 
2683 	p = kfd_lookup_process_by_pasid(pasid);
2684 	if (!p) {
2685 		pr_debug("kfd process not founded pasid 0x%x\n", pasid);
2686 		return 0;
2687 	}
2688 	svms = &p->svms;
2689 
2690 	pr_debug("restoring svms 0x%p fault address 0x%llx\n", svms, addr);
2691 
2692 	if (atomic_read(&svms->drain_pagefaults)) {
2693 		pr_debug("draining retry fault, drop fault 0x%llx\n", addr);
2694 		r = 0;
2695 		goto out;
2696 	}
2697 
2698 	if (!p->xnack_enabled) {
2699 		pr_debug("XNACK not enabled for pasid 0x%x\n", pasid);
2700 		r = -EFAULT;
2701 		goto out;
2702 	}
2703 
2704 	/* p->lead_thread is available as kfd_process_wq_release flush the work
2705 	 * before releasing task ref.
2706 	 */
2707 	mm = get_task_mm(p->lead_thread);
2708 	if (!mm) {
2709 		pr_debug("svms 0x%p failed to get mm\n", svms);
2710 		r = 0;
2711 		goto out;
2712 	}
2713 
2714 	mmap_read_lock(mm);
2715 retry_write_locked:
2716 	mutex_lock(&svms->lock);
2717 	prange = svm_range_from_addr(svms, addr, NULL);
2718 	if (!prange) {
2719 		pr_debug("failed to find prange svms 0x%p address [0x%llx]\n",
2720 			 svms, addr);
2721 		if (!write_locked) {
2722 			/* Need the write lock to create new range with MMU notifier.
2723 			 * Also flush pending deferred work to make sure the interval
2724 			 * tree is up to date before we add a new range
2725 			 */
2726 			mutex_unlock(&svms->lock);
2727 			mmap_read_unlock(mm);
2728 			mmap_write_lock(mm);
2729 			write_locked = true;
2730 			goto retry_write_locked;
2731 		}
2732 		prange = svm_range_create_unregistered_range(adev, p, mm, addr);
2733 		if (!prange) {
2734 			pr_debug("failed to create unregistered range svms 0x%p address [0x%llx]\n",
2735 				 svms, addr);
2736 			mmap_write_downgrade(mm);
2737 			r = -EFAULT;
2738 			goto out_unlock_svms;
2739 		}
2740 	}
2741 	if (write_locked)
2742 		mmap_write_downgrade(mm);
2743 
2744 	mutex_lock(&prange->migrate_mutex);
2745 
2746 	if (svm_range_skip_recover(prange)) {
2747 		amdgpu_gmc_filter_faults_remove(adev, addr, pasid);
2748 		r = 0;
2749 		goto out_unlock_range;
2750 	}
2751 
2752 	timestamp = ktime_to_us(ktime_get()) - prange->validate_timestamp;
2753 	/* skip duplicate vm fault on different pages of same range */
2754 	if (timestamp < AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING) {
2755 		pr_debug("svms 0x%p [0x%lx %lx] already restored\n",
2756 			 svms, prange->start, prange->last);
2757 		r = 0;
2758 		goto out_unlock_range;
2759 	}
2760 
2761 	/* __do_munmap removed VMA, return success as we are handling stale
2762 	 * retry fault.
2763 	 */
2764 	vma = find_vma(mm, addr << PAGE_SHIFT);
2765 	if (!vma || (addr << PAGE_SHIFT) < vma->vm_start) {
2766 		pr_debug("address 0x%llx VMA is removed\n", addr);
2767 		r = 0;
2768 		goto out_unlock_range;
2769 	}
2770 
2771 	if (!svm_fault_allowed(vma, write_fault)) {
2772 		pr_debug("fault addr 0x%llx no %s permission\n", addr,
2773 			write_fault ? "write" : "read");
2774 		r = -EPERM;
2775 		goto out_unlock_range;
2776 	}
2777 
2778 	best_loc = svm_range_best_restore_location(prange, adev, &gpuidx);
2779 	if (best_loc == -1) {
2780 		pr_debug("svms %p failed get best restore loc [0x%lx 0x%lx]\n",
2781 			 svms, prange->start, prange->last);
2782 		r = -EACCES;
2783 		goto out_unlock_range;
2784 	}
2785 
2786 	pr_debug("svms %p [0x%lx 0x%lx] best restore 0x%x, actual loc 0x%x\n",
2787 		 svms, prange->start, prange->last, best_loc,
2788 		 prange->actual_loc);
2789 
2790 	if (prange->actual_loc != best_loc) {
2791 		if (best_loc) {
2792 			r = svm_migrate_to_vram(prange, best_loc, mm);
2793 			if (r) {
2794 				pr_debug("svm_migrate_to_vram failed (%d) at %llx, falling back to system memory\n",
2795 					 r, addr);
2796 				/* Fallback to system memory if migration to
2797 				 * VRAM failed
2798 				 */
2799 				if (prange->actual_loc)
2800 					r = svm_migrate_vram_to_ram(prange, mm);
2801 				else
2802 					r = 0;
2803 			}
2804 		} else {
2805 			r = svm_migrate_vram_to_ram(prange, mm);
2806 		}
2807 		if (r) {
2808 			pr_debug("failed %d to migrate svms %p [0x%lx 0x%lx]\n",
2809 				 r, svms, prange->start, prange->last);
2810 			goto out_unlock_range;
2811 		}
2812 	}
2813 
2814 	r = svm_range_validate_and_map(mm, prange, gpuidx, false, false);
2815 	if (r)
2816 		pr_debug("failed %d to map svms 0x%p [0x%lx 0x%lx] to gpus\n",
2817 			 r, svms, prange->start, prange->last);
2818 
2819 out_unlock_range:
2820 	mutex_unlock(&prange->migrate_mutex);
2821 out_unlock_svms:
2822 	mutex_unlock(&svms->lock);
2823 	mmap_read_unlock(mm);
2824 
2825 	svm_range_count_fault(adev, p, gpuidx);
2826 
2827 	mmput(mm);
2828 out:
2829 	kfd_unref_process(p);
2830 
2831 	if (r == -EAGAIN) {
2832 		pr_debug("recover vm fault later\n");
2833 		amdgpu_gmc_filter_faults_remove(adev, addr, pasid);
2834 		r = 0;
2835 	}
2836 	return r;
2837 }
2838 
2839 void svm_range_list_fini(struct kfd_process *p)
2840 {
2841 	struct svm_range *prange;
2842 	struct svm_range *next;
2843 
2844 	pr_debug("pasid 0x%x svms 0x%p\n", p->pasid, &p->svms);
2845 
2846 	cancel_delayed_work_sync(&p->svms.restore_work);
2847 
2848 	/* Ensure list work is finished before process is destroyed */
2849 	flush_work(&p->svms.deferred_list_work);
2850 
2851 	/*
2852 	 * Ensure no retry fault comes in afterwards, as page fault handler will
2853 	 * not find kfd process and take mm lock to recover fault.
2854 	 */
2855 	atomic_inc(&p->svms.drain_pagefaults);
2856 	svm_range_drain_retry_fault(&p->svms);
2857 
2858 	list_for_each_entry_safe(prange, next, &p->svms.list, list) {
2859 		svm_range_unlink(prange);
2860 		svm_range_remove_notifier(prange);
2861 		svm_range_free(prange);
2862 	}
2863 
2864 	mutex_destroy(&p->svms.lock);
2865 
2866 	pr_debug("pasid 0x%x svms 0x%p done\n", p->pasid, &p->svms);
2867 }
2868 
2869 int svm_range_list_init(struct kfd_process *p)
2870 {
2871 	struct svm_range_list *svms = &p->svms;
2872 	int i;
2873 
2874 	svms->objects = RB_ROOT_CACHED;
2875 	mutex_init(&svms->lock);
2876 	INIT_LIST_HEAD(&svms->list);
2877 	atomic_set(&svms->evicted_ranges, 0);
2878 	atomic_set(&svms->drain_pagefaults, 0);
2879 	INIT_DELAYED_WORK(&svms->restore_work, svm_range_restore_work);
2880 	INIT_WORK(&svms->deferred_list_work, svm_range_deferred_list_work);
2881 	INIT_LIST_HEAD(&svms->deferred_range_list);
2882 	INIT_LIST_HEAD(&svms->criu_svm_metadata_list);
2883 	spin_lock_init(&svms->deferred_list_lock);
2884 
2885 	for (i = 0; i < p->n_pdds; i++)
2886 		if (KFD_IS_SVM_API_SUPPORTED(p->pdds[i]->dev))
2887 			bitmap_set(svms->bitmap_supported, i, 1);
2888 
2889 	return 0;
2890 }
2891 
2892 /**
2893  * svm_range_check_vm - check if virtual address range mapped already
2894  * @p: current kfd_process
2895  * @start: range start address, in pages
2896  * @last: range last address, in pages
2897  * @bo_s: mapping start address in pages if address range already mapped
2898  * @bo_l: mapping last address in pages if address range already mapped
2899  *
2900  * The purpose is to avoid virtual address ranges already allocated by
2901  * kfd_ioctl_alloc_memory_of_gpu ioctl.
2902  * It looks for each pdd in the kfd_process.
2903  *
2904  * Context: Process context
2905  *
2906  * Return 0 - OK, if the range is not mapped.
2907  * Otherwise error code:
2908  * -EADDRINUSE - if address is mapped already by kfd_ioctl_alloc_memory_of_gpu
2909  * -ERESTARTSYS - A wait for the buffer to become unreserved was interrupted by
2910  * a signal. Release all buffer reservations and return to user-space.
2911  */
2912 static int
2913 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
2914 		   uint64_t *bo_s, uint64_t *bo_l)
2915 {
2916 	struct amdgpu_bo_va_mapping *mapping;
2917 	struct interval_tree_node *node;
2918 	uint32_t i;
2919 	int r;
2920 
2921 	for (i = 0; i < p->n_pdds; i++) {
2922 		struct amdgpu_vm *vm;
2923 
2924 		if (!p->pdds[i]->drm_priv)
2925 			continue;
2926 
2927 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
2928 		r = amdgpu_bo_reserve(vm->root.bo, false);
2929 		if (r)
2930 			return r;
2931 
2932 		node = interval_tree_iter_first(&vm->va, start, last);
2933 		if (node) {
2934 			pr_debug("range [0x%llx 0x%llx] already TTM mapped\n",
2935 				 start, last);
2936 			mapping = container_of((struct rb_node *)node,
2937 					       struct amdgpu_bo_va_mapping, rb);
2938 			if (bo_s && bo_l) {
2939 				*bo_s = mapping->start;
2940 				*bo_l = mapping->last;
2941 			}
2942 			amdgpu_bo_unreserve(vm->root.bo);
2943 			return -EADDRINUSE;
2944 		}
2945 		amdgpu_bo_unreserve(vm->root.bo);
2946 	}
2947 
2948 	return 0;
2949 }
2950 
2951 /**
2952  * svm_range_is_valid - check if virtual address range is valid
2953  * @p: current kfd_process
2954  * @start: range start address, in pages
2955  * @size: range size, in pages
2956  *
2957  * Valid virtual address range means it belongs to one or more VMAs
2958  *
2959  * Context: Process context
2960  *
2961  * Return:
2962  *  0 - OK, otherwise error code
2963  */
2964 static int
2965 svm_range_is_valid(struct kfd_process *p, uint64_t start, uint64_t size)
2966 {
2967 	const unsigned long device_vma = VM_IO | VM_PFNMAP | VM_MIXEDMAP;
2968 	struct vm_area_struct *vma;
2969 	unsigned long end;
2970 	unsigned long start_unchg = start;
2971 
2972 	start <<= PAGE_SHIFT;
2973 	end = start + (size << PAGE_SHIFT);
2974 	do {
2975 		vma = find_vma(p->mm, start);
2976 		if (!vma || start < vma->vm_start ||
2977 		    (vma->vm_flags & device_vma))
2978 			return -EFAULT;
2979 		start = min(end, vma->vm_end);
2980 	} while (start < end);
2981 
2982 	return svm_range_check_vm(p, start_unchg, (end - 1) >> PAGE_SHIFT, NULL,
2983 				  NULL);
2984 }
2985 
2986 /**
2987  * svm_range_best_prefetch_location - decide the best prefetch location
2988  * @prange: svm range structure
2989  *
2990  * For xnack off:
2991  * If range map to single GPU, the best prefetch location is prefetch_loc, which
2992  * can be CPU or GPU.
2993  *
2994  * If range is ACCESS or ACCESS_IN_PLACE by mGPUs, only if mGPU connection on
2995  * XGMI same hive, the best prefetch location is prefetch_loc GPU, othervise
2996  * the best prefetch location is always CPU, because GPU can not have coherent
2997  * mapping VRAM of other GPUs even with large-BAR PCIe connection.
2998  *
2999  * For xnack on:
3000  * If range is not ACCESS_IN_PLACE by mGPUs, the best prefetch location is
3001  * prefetch_loc, other GPU access will generate vm fault and trigger migration.
3002  *
3003  * If range is ACCESS_IN_PLACE by mGPUs, only if mGPU connection on XGMI same
3004  * hive, the best prefetch location is prefetch_loc GPU, otherwise the best
3005  * prefetch location is always CPU.
3006  *
3007  * Context: Process context
3008  *
3009  * Return:
3010  * 0 for CPU or GPU id
3011  */
3012 static uint32_t
3013 svm_range_best_prefetch_location(struct svm_range *prange)
3014 {
3015 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
3016 	uint32_t best_loc = prange->prefetch_loc;
3017 	struct kfd_process_device *pdd;
3018 	struct amdgpu_device *bo_adev;
3019 	struct kfd_process *p;
3020 	uint32_t gpuidx;
3021 
3022 	p = container_of(prange->svms, struct kfd_process, svms);
3023 
3024 	if (!best_loc || best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED)
3025 		goto out;
3026 
3027 	bo_adev = svm_range_get_adev_by_id(prange, best_loc);
3028 	if (!bo_adev) {
3029 		WARN_ONCE(1, "failed to get device by id 0x%x\n", best_loc);
3030 		best_loc = 0;
3031 		goto out;
3032 	}
3033 
3034 	if (p->xnack_enabled)
3035 		bitmap_copy(bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
3036 	else
3037 		bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
3038 			  MAX_GPU_INSTANCE);
3039 
3040 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
3041 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
3042 		if (!pdd) {
3043 			pr_debug("failed to get device by idx 0x%x\n", gpuidx);
3044 			continue;
3045 		}
3046 
3047 		if (pdd->dev->adev == bo_adev)
3048 			continue;
3049 
3050 		if (!amdgpu_xgmi_same_hive(pdd->dev->adev, bo_adev)) {
3051 			best_loc = 0;
3052 			break;
3053 		}
3054 	}
3055 
3056 out:
3057 	pr_debug("xnack %d svms 0x%p [0x%lx 0x%lx] best loc 0x%x\n",
3058 		 p->xnack_enabled, &p->svms, prange->start, prange->last,
3059 		 best_loc);
3060 
3061 	return best_loc;
3062 }
3063 
3064 /* FIXME: This is a workaround for page locking bug when some pages are
3065  * invalid during migration to VRAM
3066  */
3067 void svm_range_prefault(struct svm_range *prange, struct mm_struct *mm,
3068 			void *owner)
3069 {
3070 	struct hmm_range *hmm_range;
3071 	int r;
3072 
3073 	if (prange->validated_once)
3074 		return;
3075 
3076 	r = amdgpu_hmm_range_get_pages(&prange->notifier, mm, NULL,
3077 				       prange->start << PAGE_SHIFT,
3078 				       prange->npages, &hmm_range,
3079 				       false, true, owner);
3080 	if (!r) {
3081 		amdgpu_hmm_range_get_pages_done(hmm_range);
3082 		prange->validated_once = true;
3083 	}
3084 }
3085 
3086 /* svm_range_trigger_migration - start page migration if prefetch loc changed
3087  * @mm: current process mm_struct
3088  * @prange: svm range structure
3089  * @migrated: output, true if migration is triggered
3090  *
3091  * If range perfetch_loc is GPU, actual loc is cpu 0, then migrate the range
3092  * from ram to vram.
3093  * If range prefetch_loc is cpu 0, actual loc is GPU, then migrate the range
3094  * from vram to ram.
3095  *
3096  * If GPU vm fault retry is not enabled, migration interact with MMU notifier
3097  * and restore work:
3098  * 1. migrate_vma_setup invalidate pages, MMU notifier callback svm_range_evict
3099  *    stops all queues, schedule restore work
3100  * 2. svm_range_restore_work wait for migration is done by
3101  *    a. svm_range_validate_vram takes prange->migrate_mutex
3102  *    b. svm_range_validate_ram HMM get pages wait for CPU fault handle returns
3103  * 3. restore work update mappings of GPU, resume all queues.
3104  *
3105  * Context: Process context
3106  *
3107  * Return:
3108  * 0 - OK, otherwise - error code of migration
3109  */
3110 static int
3111 svm_range_trigger_migration(struct mm_struct *mm, struct svm_range *prange,
3112 			    bool *migrated)
3113 {
3114 	uint32_t best_loc;
3115 	int r = 0;
3116 
3117 	*migrated = false;
3118 	best_loc = svm_range_best_prefetch_location(prange);
3119 
3120 	if (best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3121 	    best_loc == prange->actual_loc)
3122 		return 0;
3123 
3124 	if (!best_loc) {
3125 		r = svm_migrate_vram_to_ram(prange, mm);
3126 		*migrated = !r;
3127 		return r;
3128 	}
3129 
3130 	r = svm_migrate_to_vram(prange, best_loc, mm);
3131 	*migrated = !r;
3132 
3133 	return r;
3134 }
3135 
3136 int svm_range_schedule_evict_svm_bo(struct amdgpu_amdkfd_fence *fence)
3137 {
3138 	if (!fence)
3139 		return -EINVAL;
3140 
3141 	if (dma_fence_is_signaled(&fence->base))
3142 		return 0;
3143 
3144 	if (fence->svm_bo) {
3145 		WRITE_ONCE(fence->svm_bo->evicting, 1);
3146 		schedule_work(&fence->svm_bo->eviction_work);
3147 	}
3148 
3149 	return 0;
3150 }
3151 
3152 static void svm_range_evict_svm_bo_worker(struct work_struct *work)
3153 {
3154 	struct svm_range_bo *svm_bo;
3155 	struct kfd_process *p;
3156 	struct mm_struct *mm;
3157 	int r = 0;
3158 
3159 	svm_bo = container_of(work, struct svm_range_bo, eviction_work);
3160 	if (!svm_bo_ref_unless_zero(svm_bo))
3161 		return; /* svm_bo was freed while eviction was pending */
3162 
3163 	/* svm_range_bo_release destroys this worker thread. So during
3164 	 * the lifetime of this thread, kfd_process and mm will be valid.
3165 	 */
3166 	p = container_of(svm_bo->svms, struct kfd_process, svms);
3167 	mm = p->mm;
3168 	if (!mm)
3169 		return;
3170 
3171 	mmap_read_lock(mm);
3172 	spin_lock(&svm_bo->list_lock);
3173 	while (!list_empty(&svm_bo->range_list) && !r) {
3174 		struct svm_range *prange =
3175 				list_first_entry(&svm_bo->range_list,
3176 						struct svm_range, svm_bo_list);
3177 		int retries = 3;
3178 
3179 		list_del_init(&prange->svm_bo_list);
3180 		spin_unlock(&svm_bo->list_lock);
3181 
3182 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
3183 			 prange->start, prange->last);
3184 
3185 		mutex_lock(&prange->migrate_mutex);
3186 		do {
3187 			r = svm_migrate_vram_to_ram(prange,
3188 						svm_bo->eviction_fence->mm);
3189 		} while (!r && prange->actual_loc && --retries);
3190 
3191 		if (!r && prange->actual_loc)
3192 			pr_info_once("Migration failed during eviction");
3193 
3194 		if (!prange->actual_loc) {
3195 			mutex_lock(&prange->lock);
3196 			prange->svm_bo = NULL;
3197 			mutex_unlock(&prange->lock);
3198 		}
3199 		mutex_unlock(&prange->migrate_mutex);
3200 
3201 		spin_lock(&svm_bo->list_lock);
3202 	}
3203 	spin_unlock(&svm_bo->list_lock);
3204 	mmap_read_unlock(mm);
3205 
3206 	dma_fence_signal(&svm_bo->eviction_fence->base);
3207 
3208 	/* This is the last reference to svm_bo, after svm_range_vram_node_free
3209 	 * has been called in svm_migrate_vram_to_ram
3210 	 */
3211 	WARN_ONCE(!r && kref_read(&svm_bo->kref) != 1, "This was not the last reference\n");
3212 	svm_range_bo_unref(svm_bo);
3213 }
3214 
3215 static int
3216 svm_range_set_attr(struct kfd_process *p, struct mm_struct *mm,
3217 		   uint64_t start, uint64_t size, uint32_t nattr,
3218 		   struct kfd_ioctl_svm_attribute *attrs)
3219 {
3220 	struct amdkfd_process_info *process_info = p->kgd_process_info;
3221 	struct list_head update_list;
3222 	struct list_head insert_list;
3223 	struct list_head remove_list;
3224 	struct svm_range_list *svms;
3225 	struct svm_range *prange;
3226 	struct svm_range *next;
3227 	int r = 0;
3228 
3229 	pr_debug("pasid 0x%x svms 0x%p [0x%llx 0x%llx] pages 0x%llx\n",
3230 		 p->pasid, &p->svms, start, start + size - 1, size);
3231 
3232 	r = svm_range_check_attr(p, nattr, attrs);
3233 	if (r)
3234 		return r;
3235 
3236 	svms = &p->svms;
3237 
3238 	mutex_lock(&process_info->lock);
3239 
3240 	svm_range_list_lock_and_flush_work(svms, mm);
3241 
3242 	r = svm_range_is_valid(p, start, size);
3243 	if (r) {
3244 		pr_debug("invalid range r=%d\n", r);
3245 		mmap_write_unlock(mm);
3246 		goto out;
3247 	}
3248 
3249 	mutex_lock(&svms->lock);
3250 
3251 	/* Add new range and split existing ranges as needed */
3252 	r = svm_range_add(p, start, size, nattr, attrs, &update_list,
3253 			  &insert_list, &remove_list);
3254 	if (r) {
3255 		mutex_unlock(&svms->lock);
3256 		mmap_write_unlock(mm);
3257 		goto out;
3258 	}
3259 	/* Apply changes as a transaction */
3260 	list_for_each_entry_safe(prange, next, &insert_list, list) {
3261 		svm_range_add_to_svms(prange);
3262 		svm_range_add_notifier_locked(mm, prange);
3263 	}
3264 	list_for_each_entry(prange, &update_list, update_list) {
3265 		svm_range_apply_attrs(p, prange, nattr, attrs);
3266 		/* TODO: unmap ranges from GPU that lost access */
3267 	}
3268 	list_for_each_entry_safe(prange, next, &remove_list, update_list) {
3269 		pr_debug("unlink old 0x%p prange 0x%p [0x%lx 0x%lx]\n",
3270 			 prange->svms, prange, prange->start,
3271 			 prange->last);
3272 		svm_range_unlink(prange);
3273 		svm_range_remove_notifier(prange);
3274 		svm_range_free(prange);
3275 	}
3276 
3277 	mmap_write_downgrade(mm);
3278 	/* Trigger migrations and revalidate and map to GPUs as needed. If
3279 	 * this fails we may be left with partially completed actions. There
3280 	 * is no clean way of rolling back to the previous state in such a
3281 	 * case because the rollback wouldn't be guaranteed to work either.
3282 	 */
3283 	list_for_each_entry(prange, &update_list, update_list) {
3284 		bool migrated;
3285 
3286 		mutex_lock(&prange->migrate_mutex);
3287 
3288 		r = svm_range_trigger_migration(mm, prange, &migrated);
3289 		if (r)
3290 			goto out_unlock_range;
3291 
3292 		if (migrated && !p->xnack_enabled) {
3293 			pr_debug("restore_work will update mappings of GPUs\n");
3294 			mutex_unlock(&prange->migrate_mutex);
3295 			continue;
3296 		}
3297 
3298 		r = svm_range_validate_and_map(mm, prange, MAX_GPU_INSTANCE,
3299 					       true, true);
3300 		if (r)
3301 			pr_debug("failed %d to map svm range\n", r);
3302 
3303 out_unlock_range:
3304 		mutex_unlock(&prange->migrate_mutex);
3305 		if (r)
3306 			break;
3307 	}
3308 
3309 	svm_range_debug_dump(svms);
3310 
3311 	mutex_unlock(&svms->lock);
3312 	mmap_read_unlock(mm);
3313 out:
3314 	mutex_unlock(&process_info->lock);
3315 
3316 	pr_debug("pasid 0x%x svms 0x%p [0x%llx 0x%llx] done, r=%d\n", p->pasid,
3317 		 &p->svms, start, start + size - 1, r);
3318 
3319 	return r;
3320 }
3321 
3322 static int
3323 svm_range_get_attr(struct kfd_process *p, struct mm_struct *mm,
3324 		   uint64_t start, uint64_t size, uint32_t nattr,
3325 		   struct kfd_ioctl_svm_attribute *attrs)
3326 {
3327 	DECLARE_BITMAP(bitmap_access, MAX_GPU_INSTANCE);
3328 	DECLARE_BITMAP(bitmap_aip, MAX_GPU_INSTANCE);
3329 	bool get_preferred_loc = false;
3330 	bool get_prefetch_loc = false;
3331 	bool get_granularity = false;
3332 	bool get_accessible = false;
3333 	bool get_flags = false;
3334 	uint64_t last = start + size - 1UL;
3335 	uint8_t granularity = 0xff;
3336 	struct interval_tree_node *node;
3337 	struct svm_range_list *svms;
3338 	struct svm_range *prange;
3339 	uint32_t prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3340 	uint32_t location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3341 	uint32_t flags_and = 0xffffffff;
3342 	uint32_t flags_or = 0;
3343 	int gpuidx;
3344 	uint32_t i;
3345 	int r = 0;
3346 
3347 	pr_debug("svms 0x%p [0x%llx 0x%llx] nattr 0x%x\n", &p->svms, start,
3348 		 start + size - 1, nattr);
3349 
3350 	/* Flush pending deferred work to avoid racing with deferred actions from
3351 	 * previous memory map changes (e.g. munmap). Concurrent memory map changes
3352 	 * can still race with get_attr because we don't hold the mmap lock. But that
3353 	 * would be a race condition in the application anyway, and undefined
3354 	 * behaviour is acceptable in that case.
3355 	 */
3356 	flush_work(&p->svms.deferred_list_work);
3357 
3358 	mmap_read_lock(mm);
3359 	r = svm_range_is_valid(p, start, size);
3360 	mmap_read_unlock(mm);
3361 	if (r) {
3362 		pr_debug("invalid range r=%d\n", r);
3363 		return r;
3364 	}
3365 
3366 	for (i = 0; i < nattr; i++) {
3367 		switch (attrs[i].type) {
3368 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3369 			get_preferred_loc = true;
3370 			break;
3371 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3372 			get_prefetch_loc = true;
3373 			break;
3374 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3375 			get_accessible = true;
3376 			break;
3377 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3378 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3379 			get_flags = true;
3380 			break;
3381 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3382 			get_granularity = true;
3383 			break;
3384 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
3385 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
3386 			fallthrough;
3387 		default:
3388 			pr_debug("get invalid attr type 0x%x\n", attrs[i].type);
3389 			return -EINVAL;
3390 		}
3391 	}
3392 
3393 	svms = &p->svms;
3394 
3395 	mutex_lock(&svms->lock);
3396 
3397 	node = interval_tree_iter_first(&svms->objects, start, last);
3398 	if (!node) {
3399 		pr_debug("range attrs not found return default values\n");
3400 		svm_range_set_default_attributes(&location, &prefetch_loc,
3401 						 &granularity, &flags_and);
3402 		flags_or = flags_and;
3403 		if (p->xnack_enabled)
3404 			bitmap_copy(bitmap_access, svms->bitmap_supported,
3405 				    MAX_GPU_INSTANCE);
3406 		else
3407 			bitmap_zero(bitmap_access, MAX_GPU_INSTANCE);
3408 		bitmap_zero(bitmap_aip, MAX_GPU_INSTANCE);
3409 		goto fill_values;
3410 	}
3411 	bitmap_copy(bitmap_access, svms->bitmap_supported, MAX_GPU_INSTANCE);
3412 	bitmap_copy(bitmap_aip, svms->bitmap_supported, MAX_GPU_INSTANCE);
3413 
3414 	while (node) {
3415 		struct interval_tree_node *next;
3416 
3417 		prange = container_of(node, struct svm_range, it_node);
3418 		next = interval_tree_iter_next(node, start, last);
3419 
3420 		if (get_preferred_loc) {
3421 			if (prange->preferred_loc ==
3422 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3423 			    (location != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3424 			     location != prange->preferred_loc)) {
3425 				location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3426 				get_preferred_loc = false;
3427 			} else {
3428 				location = prange->preferred_loc;
3429 			}
3430 		}
3431 		if (get_prefetch_loc) {
3432 			if (prange->prefetch_loc ==
3433 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3434 			    (prefetch_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3435 			     prefetch_loc != prange->prefetch_loc)) {
3436 				prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3437 				get_prefetch_loc = false;
3438 			} else {
3439 				prefetch_loc = prange->prefetch_loc;
3440 			}
3441 		}
3442 		if (get_accessible) {
3443 			bitmap_and(bitmap_access, bitmap_access,
3444 				   prange->bitmap_access, MAX_GPU_INSTANCE);
3445 			bitmap_and(bitmap_aip, bitmap_aip,
3446 				   prange->bitmap_aip, MAX_GPU_INSTANCE);
3447 		}
3448 		if (get_flags) {
3449 			flags_and &= prange->flags;
3450 			flags_or |= prange->flags;
3451 		}
3452 
3453 		if (get_granularity && prange->granularity < granularity)
3454 			granularity = prange->granularity;
3455 
3456 		node = next;
3457 	}
3458 fill_values:
3459 	mutex_unlock(&svms->lock);
3460 
3461 	for (i = 0; i < nattr; i++) {
3462 		switch (attrs[i].type) {
3463 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3464 			attrs[i].value = location;
3465 			break;
3466 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3467 			attrs[i].value = prefetch_loc;
3468 			break;
3469 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3470 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
3471 							       attrs[i].value);
3472 			if (gpuidx < 0) {
3473 				pr_debug("invalid gpuid %x\n", attrs[i].value);
3474 				return -EINVAL;
3475 			}
3476 			if (test_bit(gpuidx, bitmap_access))
3477 				attrs[i].type = KFD_IOCTL_SVM_ATTR_ACCESS;
3478 			else if (test_bit(gpuidx, bitmap_aip))
3479 				attrs[i].type =
3480 					KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE;
3481 			else
3482 				attrs[i].type = KFD_IOCTL_SVM_ATTR_NO_ACCESS;
3483 			break;
3484 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3485 			attrs[i].value = flags_and;
3486 			break;
3487 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3488 			attrs[i].value = ~flags_or;
3489 			break;
3490 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3491 			attrs[i].value = (uint32_t)granularity;
3492 			break;
3493 		}
3494 	}
3495 
3496 	return 0;
3497 }
3498 
3499 int kfd_criu_resume_svm(struct kfd_process *p)
3500 {
3501 	struct kfd_ioctl_svm_attribute *set_attr_new, *set_attr = NULL;
3502 	int nattr_common = 4, nattr_accessibility = 1;
3503 	struct criu_svm_metadata *criu_svm_md = NULL;
3504 	struct svm_range_list *svms = &p->svms;
3505 	struct criu_svm_metadata *next = NULL;
3506 	uint32_t set_flags = 0xffffffff;
3507 	int i, j, num_attrs, ret = 0;
3508 	uint64_t set_attr_size;
3509 	struct mm_struct *mm;
3510 
3511 	if (list_empty(&svms->criu_svm_metadata_list)) {
3512 		pr_debug("No SVM data from CRIU restore stage 2\n");
3513 		return ret;
3514 	}
3515 
3516 	mm = get_task_mm(p->lead_thread);
3517 	if (!mm) {
3518 		pr_err("failed to get mm for the target process\n");
3519 		return -ESRCH;
3520 	}
3521 
3522 	num_attrs = nattr_common + (nattr_accessibility * p->n_pdds);
3523 
3524 	i = j = 0;
3525 	list_for_each_entry(criu_svm_md, &svms->criu_svm_metadata_list, list) {
3526 		pr_debug("criu_svm_md[%d]\n\tstart: 0x%llx size: 0x%llx (npages)\n",
3527 			 i, criu_svm_md->data.start_addr, criu_svm_md->data.size);
3528 
3529 		for (j = 0; j < num_attrs; j++) {
3530 			pr_debug("\ncriu_svm_md[%d]->attrs[%d].type : 0x%x\ncriu_svm_md[%d]->attrs[%d].value : 0x%x\n",
3531 				 i, j, criu_svm_md->data.attrs[j].type,
3532 				 i, j, criu_svm_md->data.attrs[j].value);
3533 			switch (criu_svm_md->data.attrs[j].type) {
3534 			/* During Checkpoint operation, the query for
3535 			 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC attribute might
3536 			 * return KFD_IOCTL_SVM_LOCATION_UNDEFINED if they were
3537 			 * not used by the range which was checkpointed. Care
3538 			 * must be taken to not restore with an invalid value
3539 			 * otherwise the gpuidx value will be invalid and
3540 			 * set_attr would eventually fail so just replace those
3541 			 * with another dummy attribute such as
3542 			 * KFD_IOCTL_SVM_ATTR_SET_FLAGS.
3543 			 */
3544 			case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3545 				if (criu_svm_md->data.attrs[j].value ==
3546 				    KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
3547 					criu_svm_md->data.attrs[j].type =
3548 						KFD_IOCTL_SVM_ATTR_SET_FLAGS;
3549 					criu_svm_md->data.attrs[j].value = 0;
3550 				}
3551 				break;
3552 			case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3553 				set_flags = criu_svm_md->data.attrs[j].value;
3554 				break;
3555 			default:
3556 				break;
3557 			}
3558 		}
3559 
3560 		/* CLR_FLAGS is not available via get_attr during checkpoint but
3561 		 * it needs to be inserted before restoring the ranges so
3562 		 * allocate extra space for it before calling set_attr
3563 		 */
3564 		set_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
3565 						(num_attrs + 1);
3566 		set_attr_new = krealloc(set_attr, set_attr_size,
3567 					    GFP_KERNEL);
3568 		if (!set_attr_new) {
3569 			ret = -ENOMEM;
3570 			goto exit;
3571 		}
3572 		set_attr = set_attr_new;
3573 
3574 		memcpy(set_attr, criu_svm_md->data.attrs, num_attrs *
3575 					sizeof(struct kfd_ioctl_svm_attribute));
3576 		set_attr[num_attrs].type = KFD_IOCTL_SVM_ATTR_CLR_FLAGS;
3577 		set_attr[num_attrs].value = ~set_flags;
3578 
3579 		ret = svm_range_set_attr(p, mm, criu_svm_md->data.start_addr,
3580 					 criu_svm_md->data.size, num_attrs + 1,
3581 					 set_attr);
3582 		if (ret) {
3583 			pr_err("CRIU: failed to set range attributes\n");
3584 			goto exit;
3585 		}
3586 
3587 		i++;
3588 	}
3589 exit:
3590 	kfree(set_attr);
3591 	list_for_each_entry_safe(criu_svm_md, next, &svms->criu_svm_metadata_list, list) {
3592 		pr_debug("freeing criu_svm_md[]\n\tstart: 0x%llx\n",
3593 						criu_svm_md->data.start_addr);
3594 		kfree(criu_svm_md);
3595 	}
3596 
3597 	mmput(mm);
3598 	return ret;
3599 
3600 }
3601 
3602 int kfd_criu_restore_svm(struct kfd_process *p,
3603 			 uint8_t __user *user_priv_ptr,
3604 			 uint64_t *priv_data_offset,
3605 			 uint64_t max_priv_data_size)
3606 {
3607 	uint64_t svm_priv_data_size, svm_object_md_size, svm_attrs_size;
3608 	int nattr_common = 4, nattr_accessibility = 1;
3609 	struct criu_svm_metadata *criu_svm_md = NULL;
3610 	struct svm_range_list *svms = &p->svms;
3611 	uint32_t num_devices;
3612 	int ret = 0;
3613 
3614 	num_devices = p->n_pdds;
3615 	/* Handle one SVM range object at a time, also the number of gpus are
3616 	 * assumed to be same on the restore node, checking must be done while
3617 	 * evaluating the topology earlier
3618 	 */
3619 
3620 	svm_attrs_size = sizeof(struct kfd_ioctl_svm_attribute) *
3621 		(nattr_common + nattr_accessibility * num_devices);
3622 	svm_object_md_size = sizeof(struct criu_svm_metadata) + svm_attrs_size;
3623 
3624 	svm_priv_data_size = sizeof(struct kfd_criu_svm_range_priv_data) +
3625 								svm_attrs_size;
3626 
3627 	criu_svm_md = kzalloc(svm_object_md_size, GFP_KERNEL);
3628 	if (!criu_svm_md) {
3629 		pr_err("failed to allocate memory to store svm metadata\n");
3630 		return -ENOMEM;
3631 	}
3632 	if (*priv_data_offset + svm_priv_data_size > max_priv_data_size) {
3633 		ret = -EINVAL;
3634 		goto exit;
3635 	}
3636 
3637 	ret = copy_from_user(&criu_svm_md->data, user_priv_ptr + *priv_data_offset,
3638 			     svm_priv_data_size);
3639 	if (ret) {
3640 		ret = -EFAULT;
3641 		goto exit;
3642 	}
3643 	*priv_data_offset += svm_priv_data_size;
3644 
3645 	list_add_tail(&criu_svm_md->list, &svms->criu_svm_metadata_list);
3646 
3647 	return 0;
3648 
3649 
3650 exit:
3651 	kfree(criu_svm_md);
3652 	return ret;
3653 }
3654 
3655 int svm_range_get_info(struct kfd_process *p, uint32_t *num_svm_ranges,
3656 		       uint64_t *svm_priv_data_size)
3657 {
3658 	uint64_t total_size, accessibility_size, common_attr_size;
3659 	int nattr_common = 4, nattr_accessibility = 1;
3660 	int num_devices = p->n_pdds;
3661 	struct svm_range_list *svms;
3662 	struct svm_range *prange;
3663 	uint32_t count = 0;
3664 
3665 	*svm_priv_data_size = 0;
3666 
3667 	svms = &p->svms;
3668 	if (!svms)
3669 		return -EINVAL;
3670 
3671 	mutex_lock(&svms->lock);
3672 	list_for_each_entry(prange, &svms->list, list) {
3673 		pr_debug("prange: 0x%p start: 0x%lx\t npages: 0x%llx\t end: 0x%llx\n",
3674 			 prange, prange->start, prange->npages,
3675 			 prange->start + prange->npages - 1);
3676 		count++;
3677 	}
3678 	mutex_unlock(&svms->lock);
3679 
3680 	*num_svm_ranges = count;
3681 	/* Only the accessbility attributes need to be queried for all the gpus
3682 	 * individually, remaining ones are spanned across the entire process
3683 	 * regardless of the various gpu nodes. Of the remaining attributes,
3684 	 * KFD_IOCTL_SVM_ATTR_CLR_FLAGS need not be saved.
3685 	 *
3686 	 * KFD_IOCTL_SVM_ATTR_PREFERRED_LOC
3687 	 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC
3688 	 * KFD_IOCTL_SVM_ATTR_SET_FLAGS
3689 	 * KFD_IOCTL_SVM_ATTR_GRANULARITY
3690 	 *
3691 	 * ** ACCESSBILITY ATTRIBUTES **
3692 	 * (Considered as one, type is altered during query, value is gpuid)
3693 	 * KFD_IOCTL_SVM_ATTR_ACCESS
3694 	 * KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE
3695 	 * KFD_IOCTL_SVM_ATTR_NO_ACCESS
3696 	 */
3697 	if (*num_svm_ranges > 0) {
3698 		common_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
3699 			nattr_common;
3700 		accessibility_size = sizeof(struct kfd_ioctl_svm_attribute) *
3701 			nattr_accessibility * num_devices;
3702 
3703 		total_size = sizeof(struct kfd_criu_svm_range_priv_data) +
3704 			common_attr_size + accessibility_size;
3705 
3706 		*svm_priv_data_size = *num_svm_ranges * total_size;
3707 	}
3708 
3709 	pr_debug("num_svm_ranges %u total_priv_size %llu\n", *num_svm_ranges,
3710 		 *svm_priv_data_size);
3711 	return 0;
3712 }
3713 
3714 int kfd_criu_checkpoint_svm(struct kfd_process *p,
3715 			    uint8_t __user *user_priv_data,
3716 			    uint64_t *priv_data_offset)
3717 {
3718 	struct kfd_criu_svm_range_priv_data *svm_priv = NULL;
3719 	struct kfd_ioctl_svm_attribute *query_attr = NULL;
3720 	uint64_t svm_priv_data_size, query_attr_size = 0;
3721 	int index, nattr_common = 4, ret = 0;
3722 	struct svm_range_list *svms;
3723 	int num_devices = p->n_pdds;
3724 	struct svm_range *prange;
3725 	struct mm_struct *mm;
3726 
3727 	svms = &p->svms;
3728 	if (!svms)
3729 		return -EINVAL;
3730 
3731 	mm = get_task_mm(p->lead_thread);
3732 	if (!mm) {
3733 		pr_err("failed to get mm for the target process\n");
3734 		return -ESRCH;
3735 	}
3736 
3737 	query_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
3738 				(nattr_common + num_devices);
3739 
3740 	query_attr = kzalloc(query_attr_size, GFP_KERNEL);
3741 	if (!query_attr) {
3742 		ret = -ENOMEM;
3743 		goto exit;
3744 	}
3745 
3746 	query_attr[0].type = KFD_IOCTL_SVM_ATTR_PREFERRED_LOC;
3747 	query_attr[1].type = KFD_IOCTL_SVM_ATTR_PREFETCH_LOC;
3748 	query_attr[2].type = KFD_IOCTL_SVM_ATTR_SET_FLAGS;
3749 	query_attr[3].type = KFD_IOCTL_SVM_ATTR_GRANULARITY;
3750 
3751 	for (index = 0; index < num_devices; index++) {
3752 		struct kfd_process_device *pdd = p->pdds[index];
3753 
3754 		query_attr[index + nattr_common].type =
3755 			KFD_IOCTL_SVM_ATTR_ACCESS;
3756 		query_attr[index + nattr_common].value = pdd->user_gpu_id;
3757 	}
3758 
3759 	svm_priv_data_size = sizeof(*svm_priv) + query_attr_size;
3760 
3761 	svm_priv = kzalloc(svm_priv_data_size, GFP_KERNEL);
3762 	if (!svm_priv) {
3763 		ret = -ENOMEM;
3764 		goto exit_query;
3765 	}
3766 
3767 	index = 0;
3768 	list_for_each_entry(prange, &svms->list, list) {
3769 
3770 		svm_priv->object_type = KFD_CRIU_OBJECT_TYPE_SVM_RANGE;
3771 		svm_priv->start_addr = prange->start;
3772 		svm_priv->size = prange->npages;
3773 		memcpy(&svm_priv->attrs, query_attr, query_attr_size);
3774 		pr_debug("CRIU: prange: 0x%p start: 0x%lx\t npages: 0x%llx end: 0x%llx\t size: 0x%llx\n",
3775 			 prange, prange->start, prange->npages,
3776 			 prange->start + prange->npages - 1,
3777 			 prange->npages * PAGE_SIZE);
3778 
3779 		ret = svm_range_get_attr(p, mm, svm_priv->start_addr,
3780 					 svm_priv->size,
3781 					 (nattr_common + num_devices),
3782 					 svm_priv->attrs);
3783 		if (ret) {
3784 			pr_err("CRIU: failed to obtain range attributes\n");
3785 			goto exit_priv;
3786 		}
3787 
3788 		if (copy_to_user(user_priv_data + *priv_data_offset, svm_priv,
3789 				 svm_priv_data_size)) {
3790 			pr_err("Failed to copy svm priv to user\n");
3791 			ret = -EFAULT;
3792 			goto exit_priv;
3793 		}
3794 
3795 		*priv_data_offset += svm_priv_data_size;
3796 
3797 	}
3798 
3799 
3800 exit_priv:
3801 	kfree(svm_priv);
3802 exit_query:
3803 	kfree(query_attr);
3804 exit:
3805 	mmput(mm);
3806 	return ret;
3807 }
3808 
3809 int
3810 svm_ioctl(struct kfd_process *p, enum kfd_ioctl_svm_op op, uint64_t start,
3811 	  uint64_t size, uint32_t nattrs, struct kfd_ioctl_svm_attribute *attrs)
3812 {
3813 	struct mm_struct *mm = current->mm;
3814 	int r;
3815 
3816 	start >>= PAGE_SHIFT;
3817 	size >>= PAGE_SHIFT;
3818 
3819 	switch (op) {
3820 	case KFD_IOCTL_SVM_OP_SET_ATTR:
3821 		r = svm_range_set_attr(p, mm, start, size, nattrs, attrs);
3822 		break;
3823 	case KFD_IOCTL_SVM_OP_GET_ATTR:
3824 		r = svm_range_get_attr(p, mm, start, size, nattrs, attrs);
3825 		break;
3826 	default:
3827 		r = EINVAL;
3828 		break;
3829 	}
3830 
3831 	return r;
3832 }
3833