xref: /linux/drivers/gpu/drm/amd/amdkfd/kfd_svm.c (revision a3a02a52bcfcbcc4a637d4b68bf1bc391c9fad02)
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 <linux/dynamic_debug.h>
27 #include <drm/ttm/ttm_tt.h>
28 #include <drm/drm_exec.h>
29 
30 #include "amdgpu_sync.h"
31 #include "amdgpu_object.h"
32 #include "amdgpu_vm.h"
33 #include "amdgpu_hmm.h"
34 #include "amdgpu.h"
35 #include "amdgpu_xgmi.h"
36 #include "kfd_priv.h"
37 #include "kfd_svm.h"
38 #include "kfd_migrate.h"
39 #include "kfd_smi_events.h"
40 
41 #ifdef dev_fmt
42 #undef dev_fmt
43 #endif
44 #define dev_fmt(fmt) "kfd_svm: %s: " fmt, __func__
45 
46 #define AMDGPU_SVM_RANGE_RESTORE_DELAY_MS 1
47 
48 /* Long enough to ensure no retry fault comes after svm range is restored and
49  * page table is updated.
50  */
51 #define AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING	(2UL * NSEC_PER_MSEC)
52 #if IS_ENABLED(CONFIG_DYNAMIC_DEBUG)
53 #define dynamic_svm_range_dump(svms) \
54 	_dynamic_func_call_no_desc("svm_range_dump", svm_range_debug_dump, svms)
55 #else
56 #define dynamic_svm_range_dump(svms) \
57 	do { if (0) svm_range_debug_dump(svms); } while (0)
58 #endif
59 
60 /* Giant svm range split into smaller ranges based on this, it is decided using
61  * minimum of all dGPU/APU 1/32 VRAM size, between 2MB to 1GB and alignment to
62  * power of 2MB.
63  */
64 static uint64_t max_svm_range_pages;
65 
66 struct criu_svm_metadata {
67 	struct list_head list;
68 	struct kfd_criu_svm_range_priv_data data;
69 };
70 
71 static void svm_range_evict_svm_bo_worker(struct work_struct *work);
72 static bool
73 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
74 				    const struct mmu_notifier_range *range,
75 				    unsigned long cur_seq);
76 static int
77 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
78 		   uint64_t *bo_s, uint64_t *bo_l);
79 static const struct mmu_interval_notifier_ops svm_range_mn_ops = {
80 	.invalidate = svm_range_cpu_invalidate_pagetables,
81 };
82 
83 /**
84  * svm_range_unlink - unlink svm_range from lists and interval tree
85  * @prange: svm range structure to be removed
86  *
87  * Remove the svm_range from the svms and svm_bo lists and the svms
88  * interval tree.
89  *
90  * Context: The caller must hold svms->lock
91  */
92 static void svm_range_unlink(struct svm_range *prange)
93 {
94 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
95 		 prange, prange->start, prange->last);
96 
97 	if (prange->svm_bo) {
98 		spin_lock(&prange->svm_bo->list_lock);
99 		list_del(&prange->svm_bo_list);
100 		spin_unlock(&prange->svm_bo->list_lock);
101 	}
102 
103 	list_del(&prange->list);
104 	if (prange->it_node.start != 0 && prange->it_node.last != 0)
105 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
106 }
107 
108 static void
109 svm_range_add_notifier_locked(struct mm_struct *mm, struct svm_range *prange)
110 {
111 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
112 		 prange, prange->start, prange->last);
113 
114 	mmu_interval_notifier_insert_locked(&prange->notifier, mm,
115 				     prange->start << PAGE_SHIFT,
116 				     prange->npages << PAGE_SHIFT,
117 				     &svm_range_mn_ops);
118 }
119 
120 /**
121  * svm_range_add_to_svms - add svm range to svms
122  * @prange: svm range structure to be added
123  *
124  * Add the svm range to svms interval tree and link list
125  *
126  * Context: The caller must hold svms->lock
127  */
128 static void svm_range_add_to_svms(struct svm_range *prange)
129 {
130 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
131 		 prange, prange->start, prange->last);
132 
133 	list_move_tail(&prange->list, &prange->svms->list);
134 	prange->it_node.start = prange->start;
135 	prange->it_node.last = prange->last;
136 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
137 }
138 
139 static void svm_range_remove_notifier(struct svm_range *prange)
140 {
141 	pr_debug("remove notifier svms 0x%p prange 0x%p [0x%lx 0x%lx]\n",
142 		 prange->svms, prange,
143 		 prange->notifier.interval_tree.start >> PAGE_SHIFT,
144 		 prange->notifier.interval_tree.last >> PAGE_SHIFT);
145 
146 	if (prange->notifier.interval_tree.start != 0 &&
147 	    prange->notifier.interval_tree.last != 0)
148 		mmu_interval_notifier_remove(&prange->notifier);
149 }
150 
151 static bool
152 svm_is_valid_dma_mapping_addr(struct device *dev, dma_addr_t dma_addr)
153 {
154 	return dma_addr && !dma_mapping_error(dev, dma_addr) &&
155 	       !(dma_addr & SVM_RANGE_VRAM_DOMAIN);
156 }
157 
158 static int
159 svm_range_dma_map_dev(struct amdgpu_device *adev, struct svm_range *prange,
160 		      unsigned long offset, unsigned long npages,
161 		      unsigned long *hmm_pfns, uint32_t gpuidx)
162 {
163 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
164 	dma_addr_t *addr = prange->dma_addr[gpuidx];
165 	struct device *dev = adev->dev;
166 	struct page *page;
167 	int i, r;
168 
169 	if (!addr) {
170 		addr = kvcalloc(prange->npages, sizeof(*addr), GFP_KERNEL);
171 		if (!addr)
172 			return -ENOMEM;
173 		prange->dma_addr[gpuidx] = addr;
174 	}
175 
176 	addr += offset;
177 	for (i = 0; i < npages; i++) {
178 		if (svm_is_valid_dma_mapping_addr(dev, addr[i]))
179 			dma_unmap_page(dev, addr[i], PAGE_SIZE, dir);
180 
181 		page = hmm_pfn_to_page(hmm_pfns[i]);
182 		if (is_zone_device_page(page)) {
183 			struct amdgpu_device *bo_adev = prange->svm_bo->node->adev;
184 
185 			addr[i] = (hmm_pfns[i] << PAGE_SHIFT) +
186 				   bo_adev->vm_manager.vram_base_offset -
187 				   bo_adev->kfd.pgmap.range.start;
188 			addr[i] |= SVM_RANGE_VRAM_DOMAIN;
189 			pr_debug_ratelimited("vram address: 0x%llx\n", addr[i]);
190 			continue;
191 		}
192 		addr[i] = dma_map_page(dev, page, 0, PAGE_SIZE, dir);
193 		r = dma_mapping_error(dev, addr[i]);
194 		if (r) {
195 			dev_err(dev, "failed %d dma_map_page\n", r);
196 			return r;
197 		}
198 		pr_debug_ratelimited("dma mapping 0x%llx for page addr 0x%lx\n",
199 				     addr[i] >> PAGE_SHIFT, page_to_pfn(page));
200 	}
201 
202 	return 0;
203 }
204 
205 static int
206 svm_range_dma_map(struct svm_range *prange, unsigned long *bitmap,
207 		  unsigned long offset, unsigned long npages,
208 		  unsigned long *hmm_pfns)
209 {
210 	struct kfd_process *p;
211 	uint32_t gpuidx;
212 	int r;
213 
214 	p = container_of(prange->svms, struct kfd_process, svms);
215 
216 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
217 		struct kfd_process_device *pdd;
218 
219 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
220 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
221 		if (!pdd) {
222 			pr_debug("failed to find device idx %d\n", gpuidx);
223 			return -EINVAL;
224 		}
225 
226 		r = svm_range_dma_map_dev(pdd->dev->adev, prange, offset, npages,
227 					  hmm_pfns, gpuidx);
228 		if (r)
229 			break;
230 	}
231 
232 	return r;
233 }
234 
235 void svm_range_dma_unmap_dev(struct device *dev, dma_addr_t *dma_addr,
236 			 unsigned long offset, unsigned long npages)
237 {
238 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
239 	int i;
240 
241 	if (!dma_addr)
242 		return;
243 
244 	for (i = offset; i < offset + npages; i++) {
245 		if (!svm_is_valid_dma_mapping_addr(dev, dma_addr[i]))
246 			continue;
247 		pr_debug_ratelimited("unmap 0x%llx\n", dma_addr[i] >> PAGE_SHIFT);
248 		dma_unmap_page(dev, dma_addr[i], PAGE_SIZE, dir);
249 		dma_addr[i] = 0;
250 	}
251 }
252 
253 void svm_range_dma_unmap(struct svm_range *prange)
254 {
255 	struct kfd_process_device *pdd;
256 	dma_addr_t *dma_addr;
257 	struct device *dev;
258 	struct kfd_process *p;
259 	uint32_t gpuidx;
260 
261 	p = container_of(prange->svms, struct kfd_process, svms);
262 
263 	for (gpuidx = 0; gpuidx < MAX_GPU_INSTANCE; gpuidx++) {
264 		dma_addr = prange->dma_addr[gpuidx];
265 		if (!dma_addr)
266 			continue;
267 
268 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
269 		if (!pdd) {
270 			pr_debug("failed to find device idx %d\n", gpuidx);
271 			continue;
272 		}
273 		dev = &pdd->dev->adev->pdev->dev;
274 
275 		svm_range_dma_unmap_dev(dev, dma_addr, 0, prange->npages);
276 	}
277 }
278 
279 static void svm_range_free(struct svm_range *prange, bool do_unmap)
280 {
281 	uint64_t size = (prange->last - prange->start + 1) << PAGE_SHIFT;
282 	struct kfd_process *p = container_of(prange->svms, struct kfd_process, svms);
283 	uint32_t gpuidx;
284 
285 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms, prange,
286 		 prange->start, prange->last);
287 
288 	svm_range_vram_node_free(prange);
289 	if (do_unmap)
290 		svm_range_dma_unmap(prange);
291 
292 	if (do_unmap && !p->xnack_enabled) {
293 		pr_debug("unreserve prange 0x%p size: 0x%llx\n", prange, size);
294 		amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
295 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
296 	}
297 
298 	/* free dma_addr array for each gpu */
299 	for (gpuidx = 0; gpuidx < MAX_GPU_INSTANCE; gpuidx++) {
300 		if (prange->dma_addr[gpuidx]) {
301 			kvfree(prange->dma_addr[gpuidx]);
302 			prange->dma_addr[gpuidx] = NULL;
303 		}
304 	}
305 
306 	mutex_destroy(&prange->lock);
307 	mutex_destroy(&prange->migrate_mutex);
308 	kfree(prange);
309 }
310 
311 static void
312 svm_range_set_default_attributes(int32_t *location, int32_t *prefetch_loc,
313 				 uint8_t *granularity, uint32_t *flags)
314 {
315 	*location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
316 	*prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
317 	*granularity = 9;
318 	*flags =
319 		KFD_IOCTL_SVM_FLAG_HOST_ACCESS | KFD_IOCTL_SVM_FLAG_COHERENT;
320 }
321 
322 static struct
323 svm_range *svm_range_new(struct svm_range_list *svms, uint64_t start,
324 			 uint64_t last, bool update_mem_usage)
325 {
326 	uint64_t size = last - start + 1;
327 	struct svm_range *prange;
328 	struct kfd_process *p;
329 
330 	prange = kzalloc(sizeof(*prange), GFP_KERNEL);
331 	if (!prange)
332 		return NULL;
333 
334 	p = container_of(svms, struct kfd_process, svms);
335 	if (!p->xnack_enabled && update_mem_usage &&
336 	    amdgpu_amdkfd_reserve_mem_limit(NULL, size << PAGE_SHIFT,
337 				    KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0)) {
338 		pr_info("SVM mapping failed, exceeds resident system memory limit\n");
339 		kfree(prange);
340 		return NULL;
341 	}
342 	prange->npages = size;
343 	prange->svms = svms;
344 	prange->start = start;
345 	prange->last = last;
346 	INIT_LIST_HEAD(&prange->list);
347 	INIT_LIST_HEAD(&prange->update_list);
348 	INIT_LIST_HEAD(&prange->svm_bo_list);
349 	INIT_LIST_HEAD(&prange->deferred_list);
350 	INIT_LIST_HEAD(&prange->child_list);
351 	atomic_set(&prange->invalid, 0);
352 	prange->validate_timestamp = 0;
353 	prange->vram_pages = 0;
354 	mutex_init(&prange->migrate_mutex);
355 	mutex_init(&prange->lock);
356 
357 	if (p->xnack_enabled)
358 		bitmap_copy(prange->bitmap_access, svms->bitmap_supported,
359 			    MAX_GPU_INSTANCE);
360 
361 	svm_range_set_default_attributes(&prange->preferred_loc,
362 					 &prange->prefetch_loc,
363 					 &prange->granularity, &prange->flags);
364 
365 	pr_debug("svms 0x%p [0x%llx 0x%llx]\n", svms, start, last);
366 
367 	return prange;
368 }
369 
370 static bool svm_bo_ref_unless_zero(struct svm_range_bo *svm_bo)
371 {
372 	if (!svm_bo || !kref_get_unless_zero(&svm_bo->kref))
373 		return false;
374 
375 	return true;
376 }
377 
378 static void svm_range_bo_release(struct kref *kref)
379 {
380 	struct svm_range_bo *svm_bo;
381 
382 	svm_bo = container_of(kref, struct svm_range_bo, kref);
383 	pr_debug("svm_bo 0x%p\n", svm_bo);
384 
385 	spin_lock(&svm_bo->list_lock);
386 	while (!list_empty(&svm_bo->range_list)) {
387 		struct svm_range *prange =
388 				list_first_entry(&svm_bo->range_list,
389 						struct svm_range, svm_bo_list);
390 		/* list_del_init tells a concurrent svm_range_vram_node_new when
391 		 * it's safe to reuse the svm_bo pointer and svm_bo_list head.
392 		 */
393 		list_del_init(&prange->svm_bo_list);
394 		spin_unlock(&svm_bo->list_lock);
395 
396 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
397 			 prange->start, prange->last);
398 		mutex_lock(&prange->lock);
399 		prange->svm_bo = NULL;
400 		/* prange should not hold vram page now */
401 		WARN_ONCE(prange->actual_loc, "prange should not hold vram page");
402 		mutex_unlock(&prange->lock);
403 
404 		spin_lock(&svm_bo->list_lock);
405 	}
406 	spin_unlock(&svm_bo->list_lock);
407 	if (!dma_fence_is_signaled(&svm_bo->eviction_fence->base))
408 		/* We're not in the eviction worker. Signal the fence. */
409 		dma_fence_signal(&svm_bo->eviction_fence->base);
410 	dma_fence_put(&svm_bo->eviction_fence->base);
411 	amdgpu_bo_unref(&svm_bo->bo);
412 	kfree(svm_bo);
413 }
414 
415 static void svm_range_bo_wq_release(struct work_struct *work)
416 {
417 	struct svm_range_bo *svm_bo;
418 
419 	svm_bo = container_of(work, struct svm_range_bo, release_work);
420 	svm_range_bo_release(&svm_bo->kref);
421 }
422 
423 static void svm_range_bo_release_async(struct kref *kref)
424 {
425 	struct svm_range_bo *svm_bo;
426 
427 	svm_bo = container_of(kref, struct svm_range_bo, kref);
428 	pr_debug("svm_bo 0x%p\n", svm_bo);
429 	INIT_WORK(&svm_bo->release_work, svm_range_bo_wq_release);
430 	schedule_work(&svm_bo->release_work);
431 }
432 
433 void svm_range_bo_unref_async(struct svm_range_bo *svm_bo)
434 {
435 	kref_put(&svm_bo->kref, svm_range_bo_release_async);
436 }
437 
438 static void svm_range_bo_unref(struct svm_range_bo *svm_bo)
439 {
440 	if (svm_bo)
441 		kref_put(&svm_bo->kref, svm_range_bo_release);
442 }
443 
444 static bool
445 svm_range_validate_svm_bo(struct kfd_node *node, struct svm_range *prange)
446 {
447 	mutex_lock(&prange->lock);
448 	if (!prange->svm_bo) {
449 		mutex_unlock(&prange->lock);
450 		return false;
451 	}
452 	if (prange->ttm_res) {
453 		/* We still have a reference, all is well */
454 		mutex_unlock(&prange->lock);
455 		return true;
456 	}
457 	if (svm_bo_ref_unless_zero(prange->svm_bo)) {
458 		/*
459 		 * Migrate from GPU to GPU, remove range from source svm_bo->node
460 		 * range list, and return false to allocate svm_bo from destination
461 		 * node.
462 		 */
463 		if (prange->svm_bo->node != node) {
464 			mutex_unlock(&prange->lock);
465 
466 			spin_lock(&prange->svm_bo->list_lock);
467 			list_del_init(&prange->svm_bo_list);
468 			spin_unlock(&prange->svm_bo->list_lock);
469 
470 			svm_range_bo_unref(prange->svm_bo);
471 			return false;
472 		}
473 		if (READ_ONCE(prange->svm_bo->evicting)) {
474 			struct dma_fence *f;
475 			struct svm_range_bo *svm_bo;
476 			/* The BO is getting evicted,
477 			 * we need to get a new one
478 			 */
479 			mutex_unlock(&prange->lock);
480 			svm_bo = prange->svm_bo;
481 			f = dma_fence_get(&svm_bo->eviction_fence->base);
482 			svm_range_bo_unref(prange->svm_bo);
483 			/* wait for the fence to avoid long spin-loop
484 			 * at list_empty_careful
485 			 */
486 			dma_fence_wait(f, false);
487 			dma_fence_put(f);
488 		} else {
489 			/* The BO was still around and we got
490 			 * a new reference to it
491 			 */
492 			mutex_unlock(&prange->lock);
493 			pr_debug("reuse old bo svms 0x%p [0x%lx 0x%lx]\n",
494 				 prange->svms, prange->start, prange->last);
495 
496 			prange->ttm_res = prange->svm_bo->bo->tbo.resource;
497 			return true;
498 		}
499 
500 	} else {
501 		mutex_unlock(&prange->lock);
502 	}
503 
504 	/* We need a new svm_bo. Spin-loop to wait for concurrent
505 	 * svm_range_bo_release to finish removing this range from
506 	 * its range list and set prange->svm_bo to null. After this,
507 	 * it is safe to reuse the svm_bo pointer and svm_bo_list head.
508 	 */
509 	while (!list_empty_careful(&prange->svm_bo_list) || prange->svm_bo)
510 		cond_resched();
511 
512 	return false;
513 }
514 
515 static struct svm_range_bo *svm_range_bo_new(void)
516 {
517 	struct svm_range_bo *svm_bo;
518 
519 	svm_bo = kzalloc(sizeof(*svm_bo), GFP_KERNEL);
520 	if (!svm_bo)
521 		return NULL;
522 
523 	kref_init(&svm_bo->kref);
524 	INIT_LIST_HEAD(&svm_bo->range_list);
525 	spin_lock_init(&svm_bo->list_lock);
526 
527 	return svm_bo;
528 }
529 
530 int
531 svm_range_vram_node_new(struct kfd_node *node, struct svm_range *prange,
532 			bool clear)
533 {
534 	struct amdgpu_bo_param bp;
535 	struct svm_range_bo *svm_bo;
536 	struct amdgpu_bo_user *ubo;
537 	struct amdgpu_bo *bo;
538 	struct kfd_process *p;
539 	struct mm_struct *mm;
540 	int r;
541 
542 	p = container_of(prange->svms, struct kfd_process, svms);
543 	pr_debug("pasid: %x svms 0x%p [0x%lx 0x%lx]\n", p->pasid, prange->svms,
544 		 prange->start, prange->last);
545 
546 	if (svm_range_validate_svm_bo(node, prange))
547 		return 0;
548 
549 	svm_bo = svm_range_bo_new();
550 	if (!svm_bo) {
551 		pr_debug("failed to alloc svm bo\n");
552 		return -ENOMEM;
553 	}
554 	mm = get_task_mm(p->lead_thread);
555 	if (!mm) {
556 		pr_debug("failed to get mm\n");
557 		kfree(svm_bo);
558 		return -ESRCH;
559 	}
560 	svm_bo->node = node;
561 	svm_bo->eviction_fence =
562 		amdgpu_amdkfd_fence_create(dma_fence_context_alloc(1),
563 					   mm,
564 					   svm_bo);
565 	mmput(mm);
566 	INIT_WORK(&svm_bo->eviction_work, svm_range_evict_svm_bo_worker);
567 	svm_bo->evicting = 0;
568 	memset(&bp, 0, sizeof(bp));
569 	bp.size = prange->npages * PAGE_SIZE;
570 	bp.byte_align = PAGE_SIZE;
571 	bp.domain = AMDGPU_GEM_DOMAIN_VRAM;
572 	bp.flags = AMDGPU_GEM_CREATE_NO_CPU_ACCESS;
573 	bp.flags |= clear ? AMDGPU_GEM_CREATE_VRAM_CLEARED : 0;
574 	bp.flags |= AMDGPU_GEM_CREATE_DISCARDABLE;
575 	bp.type = ttm_bo_type_device;
576 	bp.resv = NULL;
577 	if (node->xcp)
578 		bp.xcp_id_plus1 = node->xcp->id + 1;
579 
580 	r = amdgpu_bo_create_user(node->adev, &bp, &ubo);
581 	if (r) {
582 		pr_debug("failed %d to create bo\n", r);
583 		goto create_bo_failed;
584 	}
585 	bo = &ubo->bo;
586 
587 	pr_debug("alloc bo at offset 0x%lx size 0x%lx on partition %d\n",
588 		 bo->tbo.resource->start << PAGE_SHIFT, bp.size,
589 		 bp.xcp_id_plus1 - 1);
590 
591 	r = amdgpu_bo_reserve(bo, true);
592 	if (r) {
593 		pr_debug("failed %d to reserve bo\n", r);
594 		goto reserve_bo_failed;
595 	}
596 
597 	if (clear) {
598 		r = amdgpu_bo_sync_wait(bo, AMDGPU_FENCE_OWNER_KFD, false);
599 		if (r) {
600 			pr_debug("failed %d to sync bo\n", r);
601 			amdgpu_bo_unreserve(bo);
602 			goto reserve_bo_failed;
603 		}
604 	}
605 
606 	r = dma_resv_reserve_fences(bo->tbo.base.resv, 1);
607 	if (r) {
608 		pr_debug("failed %d to reserve bo\n", r);
609 		amdgpu_bo_unreserve(bo);
610 		goto reserve_bo_failed;
611 	}
612 	amdgpu_bo_fence(bo, &svm_bo->eviction_fence->base, true);
613 
614 	amdgpu_bo_unreserve(bo);
615 
616 	svm_bo->bo = bo;
617 	prange->svm_bo = svm_bo;
618 	prange->ttm_res = bo->tbo.resource;
619 	prange->offset = 0;
620 
621 	spin_lock(&svm_bo->list_lock);
622 	list_add(&prange->svm_bo_list, &svm_bo->range_list);
623 	spin_unlock(&svm_bo->list_lock);
624 
625 	return 0;
626 
627 reserve_bo_failed:
628 	amdgpu_bo_unref(&bo);
629 create_bo_failed:
630 	dma_fence_put(&svm_bo->eviction_fence->base);
631 	kfree(svm_bo);
632 	prange->ttm_res = NULL;
633 
634 	return r;
635 }
636 
637 void svm_range_vram_node_free(struct svm_range *prange)
638 {
639 	/* serialize prange->svm_bo unref */
640 	mutex_lock(&prange->lock);
641 	/* prange->svm_bo has not been unref */
642 	if (prange->ttm_res) {
643 		prange->ttm_res = NULL;
644 		mutex_unlock(&prange->lock);
645 		svm_range_bo_unref(prange->svm_bo);
646 	} else
647 		mutex_unlock(&prange->lock);
648 }
649 
650 struct kfd_node *
651 svm_range_get_node_by_id(struct svm_range *prange, uint32_t gpu_id)
652 {
653 	struct kfd_process *p;
654 	struct kfd_process_device *pdd;
655 
656 	p = container_of(prange->svms, struct kfd_process, svms);
657 	pdd = kfd_process_device_data_by_id(p, gpu_id);
658 	if (!pdd) {
659 		pr_debug("failed to get kfd process device by id 0x%x\n", gpu_id);
660 		return NULL;
661 	}
662 
663 	return pdd->dev;
664 }
665 
666 struct kfd_process_device *
667 svm_range_get_pdd_by_node(struct svm_range *prange, struct kfd_node *node)
668 {
669 	struct kfd_process *p;
670 
671 	p = container_of(prange->svms, struct kfd_process, svms);
672 
673 	return kfd_get_process_device_data(node, p);
674 }
675 
676 static int svm_range_bo_validate(void *param, struct amdgpu_bo *bo)
677 {
678 	struct ttm_operation_ctx ctx = { false, false };
679 
680 	amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_VRAM);
681 
682 	return ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
683 }
684 
685 static int
686 svm_range_check_attr(struct kfd_process *p,
687 		     uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
688 {
689 	uint32_t i;
690 
691 	for (i = 0; i < nattr; i++) {
692 		uint32_t val = attrs[i].value;
693 		int gpuidx = MAX_GPU_INSTANCE;
694 
695 		switch (attrs[i].type) {
696 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
697 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM &&
698 			    val != KFD_IOCTL_SVM_LOCATION_UNDEFINED)
699 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
700 			break;
701 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
702 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM)
703 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
704 			break;
705 		case KFD_IOCTL_SVM_ATTR_ACCESS:
706 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
707 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
708 			gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
709 			break;
710 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
711 			break;
712 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
713 			break;
714 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
715 			break;
716 		default:
717 			pr_debug("unknown attr type 0x%x\n", attrs[i].type);
718 			return -EINVAL;
719 		}
720 
721 		if (gpuidx < 0) {
722 			pr_debug("no GPU 0x%x found\n", val);
723 			return -EINVAL;
724 		} else if (gpuidx < MAX_GPU_INSTANCE &&
725 			   !test_bit(gpuidx, p->svms.bitmap_supported)) {
726 			pr_debug("GPU 0x%x not supported\n", val);
727 			return -EINVAL;
728 		}
729 	}
730 
731 	return 0;
732 }
733 
734 static void
735 svm_range_apply_attrs(struct kfd_process *p, struct svm_range *prange,
736 		      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
737 		      bool *update_mapping)
738 {
739 	uint32_t i;
740 	int gpuidx;
741 
742 	for (i = 0; i < nattr; i++) {
743 		switch (attrs[i].type) {
744 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
745 			prange->preferred_loc = attrs[i].value;
746 			break;
747 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
748 			prange->prefetch_loc = attrs[i].value;
749 			break;
750 		case KFD_IOCTL_SVM_ATTR_ACCESS:
751 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
752 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
753 			if (!p->xnack_enabled)
754 				*update_mapping = true;
755 
756 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
757 							       attrs[i].value);
758 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
759 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
760 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
761 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
762 				bitmap_set(prange->bitmap_access, gpuidx, 1);
763 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
764 			} else {
765 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
766 				bitmap_set(prange->bitmap_aip, gpuidx, 1);
767 			}
768 			break;
769 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
770 			*update_mapping = true;
771 			prange->flags |= attrs[i].value;
772 			break;
773 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
774 			*update_mapping = true;
775 			prange->flags &= ~attrs[i].value;
776 			break;
777 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
778 			prange->granularity = min_t(uint32_t, attrs[i].value, 0x3F);
779 			break;
780 		default:
781 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
782 		}
783 	}
784 }
785 
786 static bool
787 svm_range_is_same_attrs(struct kfd_process *p, struct svm_range *prange,
788 			uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
789 {
790 	uint32_t i;
791 	int gpuidx;
792 
793 	for (i = 0; i < nattr; i++) {
794 		switch (attrs[i].type) {
795 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
796 			if (prange->preferred_loc != attrs[i].value)
797 				return false;
798 			break;
799 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
800 			/* Prefetch should always trigger a migration even
801 			 * if the value of the attribute didn't change.
802 			 */
803 			return false;
804 		case KFD_IOCTL_SVM_ATTR_ACCESS:
805 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
806 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
807 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
808 							       attrs[i].value);
809 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
810 				if (test_bit(gpuidx, prange->bitmap_access) ||
811 				    test_bit(gpuidx, prange->bitmap_aip))
812 					return false;
813 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
814 				if (!test_bit(gpuidx, prange->bitmap_access))
815 					return false;
816 			} else {
817 				if (!test_bit(gpuidx, prange->bitmap_aip))
818 					return false;
819 			}
820 			break;
821 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
822 			if ((prange->flags & attrs[i].value) != attrs[i].value)
823 				return false;
824 			break;
825 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
826 			if ((prange->flags & attrs[i].value) != 0)
827 				return false;
828 			break;
829 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
830 			if (prange->granularity != attrs[i].value)
831 				return false;
832 			break;
833 		default:
834 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
835 		}
836 	}
837 
838 	return true;
839 }
840 
841 /**
842  * svm_range_debug_dump - print all range information from svms
843  * @svms: svm range list header
844  *
845  * debug output svm range start, end, prefetch location from svms
846  * interval tree and link list
847  *
848  * Context: The caller must hold svms->lock
849  */
850 static void svm_range_debug_dump(struct svm_range_list *svms)
851 {
852 	struct interval_tree_node *node;
853 	struct svm_range *prange;
854 
855 	pr_debug("dump svms 0x%p list\n", svms);
856 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
857 
858 	list_for_each_entry(prange, &svms->list, list) {
859 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
860 			 prange, prange->start, prange->npages,
861 			 prange->start + prange->npages - 1,
862 			 prange->actual_loc);
863 	}
864 
865 	pr_debug("dump svms 0x%p interval tree\n", svms);
866 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
867 	node = interval_tree_iter_first(&svms->objects, 0, ~0ULL);
868 	while (node) {
869 		prange = container_of(node, struct svm_range, it_node);
870 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
871 			 prange, prange->start, prange->npages,
872 			 prange->start + prange->npages - 1,
873 			 prange->actual_loc);
874 		node = interval_tree_iter_next(node, 0, ~0ULL);
875 	}
876 }
877 
878 static void *
879 svm_range_copy_array(void *psrc, size_t size, uint64_t num_elements,
880 		     uint64_t offset, uint64_t *vram_pages)
881 {
882 	unsigned char *src = (unsigned char *)psrc + offset;
883 	unsigned char *dst;
884 	uint64_t i;
885 
886 	dst = kvmalloc_array(num_elements, size, GFP_KERNEL);
887 	if (!dst)
888 		return NULL;
889 
890 	if (!vram_pages) {
891 		memcpy(dst, src, num_elements * size);
892 		return (void *)dst;
893 	}
894 
895 	*vram_pages = 0;
896 	for (i = 0; i < num_elements; i++) {
897 		dma_addr_t *temp;
898 		temp = (dma_addr_t *)dst + i;
899 		*temp = *((dma_addr_t *)src + i);
900 		if (*temp&SVM_RANGE_VRAM_DOMAIN)
901 			(*vram_pages)++;
902 	}
903 
904 	return (void *)dst;
905 }
906 
907 static int
908 svm_range_copy_dma_addrs(struct svm_range *dst, struct svm_range *src)
909 {
910 	int i;
911 
912 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
913 		if (!src->dma_addr[i])
914 			continue;
915 		dst->dma_addr[i] = svm_range_copy_array(src->dma_addr[i],
916 					sizeof(*src->dma_addr[i]), src->npages, 0, NULL);
917 		if (!dst->dma_addr[i])
918 			return -ENOMEM;
919 	}
920 
921 	return 0;
922 }
923 
924 static int
925 svm_range_split_array(void *ppnew, void *ppold, size_t size,
926 		      uint64_t old_start, uint64_t old_n,
927 		      uint64_t new_start, uint64_t new_n, uint64_t *new_vram_pages)
928 {
929 	unsigned char *new, *old, *pold;
930 	uint64_t d;
931 
932 	if (!ppold)
933 		return 0;
934 	pold = *(unsigned char **)ppold;
935 	if (!pold)
936 		return 0;
937 
938 	d = (new_start - old_start) * size;
939 	/* get dma addr array for new range and calculte its vram page number */
940 	new = svm_range_copy_array(pold, size, new_n, d, new_vram_pages);
941 	if (!new)
942 		return -ENOMEM;
943 	d = (new_start == old_start) ? new_n * size : 0;
944 	old = svm_range_copy_array(pold, size, old_n, d, NULL);
945 	if (!old) {
946 		kvfree(new);
947 		return -ENOMEM;
948 	}
949 	kvfree(pold);
950 	*(void **)ppold = old;
951 	*(void **)ppnew = new;
952 
953 	return 0;
954 }
955 
956 static int
957 svm_range_split_pages(struct svm_range *new, struct svm_range *old,
958 		      uint64_t start, uint64_t last)
959 {
960 	uint64_t npages = last - start + 1;
961 	int i, r;
962 
963 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
964 		r = svm_range_split_array(&new->dma_addr[i], &old->dma_addr[i],
965 					  sizeof(*old->dma_addr[i]), old->start,
966 					  npages, new->start, new->npages,
967 					  old->actual_loc ? &new->vram_pages : NULL);
968 		if (r)
969 			return r;
970 	}
971 	if (old->actual_loc)
972 		old->vram_pages -= new->vram_pages;
973 
974 	return 0;
975 }
976 
977 static int
978 svm_range_split_nodes(struct svm_range *new, struct svm_range *old,
979 		      uint64_t start, uint64_t last)
980 {
981 	uint64_t npages = last - start + 1;
982 
983 	pr_debug("svms 0x%p new prange 0x%p start 0x%lx [0x%llx 0x%llx]\n",
984 		 new->svms, new, new->start, start, last);
985 
986 	if (new->start == old->start) {
987 		new->offset = old->offset;
988 		old->offset += new->npages;
989 	} else {
990 		new->offset = old->offset + npages;
991 	}
992 
993 	new->svm_bo = svm_range_bo_ref(old->svm_bo);
994 	new->ttm_res = old->ttm_res;
995 
996 	spin_lock(&new->svm_bo->list_lock);
997 	list_add(&new->svm_bo_list, &new->svm_bo->range_list);
998 	spin_unlock(&new->svm_bo->list_lock);
999 
1000 	return 0;
1001 }
1002 
1003 /**
1004  * svm_range_split_adjust - split range and adjust
1005  *
1006  * @new: new range
1007  * @old: the old range
1008  * @start: the old range adjust to start address in pages
1009  * @last: the old range adjust to last address in pages
1010  *
1011  * Copy system memory dma_addr or vram ttm_res in old range to new
1012  * range from new_start up to size new->npages, the remaining old range is from
1013  * start to last
1014  *
1015  * Return:
1016  * 0 - OK, -ENOMEM - out of memory
1017  */
1018 static int
1019 svm_range_split_adjust(struct svm_range *new, struct svm_range *old,
1020 		      uint64_t start, uint64_t last)
1021 {
1022 	int r;
1023 
1024 	pr_debug("svms 0x%p new 0x%lx old [0x%lx 0x%lx] => [0x%llx 0x%llx]\n",
1025 		 new->svms, new->start, old->start, old->last, start, last);
1026 
1027 	if (new->start < old->start ||
1028 	    new->last > old->last) {
1029 		WARN_ONCE(1, "invalid new range start or last\n");
1030 		return -EINVAL;
1031 	}
1032 
1033 	r = svm_range_split_pages(new, old, start, last);
1034 	if (r)
1035 		return r;
1036 
1037 	if (old->actual_loc && old->ttm_res) {
1038 		r = svm_range_split_nodes(new, old, start, last);
1039 		if (r)
1040 			return r;
1041 	}
1042 
1043 	old->npages = last - start + 1;
1044 	old->start = start;
1045 	old->last = last;
1046 	new->flags = old->flags;
1047 	new->preferred_loc = old->preferred_loc;
1048 	new->prefetch_loc = old->prefetch_loc;
1049 	new->actual_loc = old->actual_loc;
1050 	new->granularity = old->granularity;
1051 	new->mapped_to_gpu = old->mapped_to_gpu;
1052 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
1053 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
1054 
1055 	return 0;
1056 }
1057 
1058 /**
1059  * svm_range_split - split a range in 2 ranges
1060  *
1061  * @prange: the svm range to split
1062  * @start: the remaining range start address in pages
1063  * @last: the remaining range last address in pages
1064  * @new: the result new range generated
1065  *
1066  * Two cases only:
1067  * case 1: if start == prange->start
1068  *         prange ==> prange[start, last]
1069  *         new range [last + 1, prange->last]
1070  *
1071  * case 2: if last == prange->last
1072  *         prange ==> prange[start, last]
1073  *         new range [prange->start, start - 1]
1074  *
1075  * Return:
1076  * 0 - OK, -ENOMEM - out of memory, -EINVAL - invalid start, last
1077  */
1078 static int
1079 svm_range_split(struct svm_range *prange, uint64_t start, uint64_t last,
1080 		struct svm_range **new)
1081 {
1082 	uint64_t old_start = prange->start;
1083 	uint64_t old_last = prange->last;
1084 	struct svm_range_list *svms;
1085 	int r = 0;
1086 
1087 	pr_debug("svms 0x%p [0x%llx 0x%llx] to [0x%llx 0x%llx]\n", prange->svms,
1088 		 old_start, old_last, start, last);
1089 
1090 	if (old_start != start && old_last != last)
1091 		return -EINVAL;
1092 	if (start < old_start || last > old_last)
1093 		return -EINVAL;
1094 
1095 	svms = prange->svms;
1096 	if (old_start == start)
1097 		*new = svm_range_new(svms, last + 1, old_last, false);
1098 	else
1099 		*new = svm_range_new(svms, old_start, start - 1, false);
1100 	if (!*new)
1101 		return -ENOMEM;
1102 
1103 	r = svm_range_split_adjust(*new, prange, start, last);
1104 	if (r) {
1105 		pr_debug("failed %d split [0x%llx 0x%llx] to [0x%llx 0x%llx]\n",
1106 			 r, old_start, old_last, start, last);
1107 		svm_range_free(*new, false);
1108 		*new = NULL;
1109 	}
1110 
1111 	return r;
1112 }
1113 
1114 static int
1115 svm_range_split_tail(struct svm_range *prange, uint64_t new_last,
1116 		     struct list_head *insert_list, struct list_head *remap_list)
1117 {
1118 	struct svm_range *tail = NULL;
1119 	int r = svm_range_split(prange, prange->start, new_last, &tail);
1120 
1121 	if (!r) {
1122 		list_add(&tail->list, insert_list);
1123 		if (!IS_ALIGNED(new_last + 1, 1UL << prange->granularity))
1124 			list_add(&tail->update_list, remap_list);
1125 	}
1126 	return r;
1127 }
1128 
1129 static int
1130 svm_range_split_head(struct svm_range *prange, uint64_t new_start,
1131 		     struct list_head *insert_list, struct list_head *remap_list)
1132 {
1133 	struct svm_range *head = NULL;
1134 	int r = svm_range_split(prange, new_start, prange->last, &head);
1135 
1136 	if (!r) {
1137 		list_add(&head->list, insert_list);
1138 		if (!IS_ALIGNED(new_start, 1UL << prange->granularity))
1139 			list_add(&head->update_list, remap_list);
1140 	}
1141 	return r;
1142 }
1143 
1144 static void
1145 svm_range_add_child(struct svm_range *prange, struct mm_struct *mm,
1146 		    struct svm_range *pchild, enum svm_work_list_ops op)
1147 {
1148 	pr_debug("add child 0x%p [0x%lx 0x%lx] to prange 0x%p child list %d\n",
1149 		 pchild, pchild->start, pchild->last, prange, op);
1150 
1151 	pchild->work_item.mm = mm;
1152 	pchild->work_item.op = op;
1153 	list_add_tail(&pchild->child_list, &prange->child_list);
1154 }
1155 
1156 static bool
1157 svm_nodes_in_same_hive(struct kfd_node *node_a, struct kfd_node *node_b)
1158 {
1159 	return (node_a->adev == node_b->adev ||
1160 		amdgpu_xgmi_same_hive(node_a->adev, node_b->adev));
1161 }
1162 
1163 static uint64_t
1164 svm_range_get_pte_flags(struct kfd_node *node,
1165 			struct svm_range *prange, int domain)
1166 {
1167 	struct kfd_node *bo_node;
1168 	uint32_t flags = prange->flags;
1169 	uint32_t mapping_flags = 0;
1170 	uint64_t pte_flags;
1171 	bool snoop = (domain != SVM_RANGE_VRAM_DOMAIN);
1172 	bool coherent = flags & (KFD_IOCTL_SVM_FLAG_COHERENT | KFD_IOCTL_SVM_FLAG_EXT_COHERENT);
1173 	bool ext_coherent = flags & KFD_IOCTL_SVM_FLAG_EXT_COHERENT;
1174 	unsigned int mtype_local;
1175 
1176 	if (domain == SVM_RANGE_VRAM_DOMAIN)
1177 		bo_node = prange->svm_bo->node;
1178 
1179 	switch (amdgpu_ip_version(node->adev, GC_HWIP, 0)) {
1180 	case IP_VERSION(9, 4, 1):
1181 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1182 			if (bo_node == node) {
1183 				mapping_flags |= coherent ?
1184 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1185 			} else {
1186 				mapping_flags |= coherent ?
1187 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1188 				if (svm_nodes_in_same_hive(node, bo_node))
1189 					snoop = true;
1190 			}
1191 		} else {
1192 			mapping_flags |= coherent ?
1193 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1194 		}
1195 		break;
1196 	case IP_VERSION(9, 4, 2):
1197 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1198 			if (bo_node == node) {
1199 				mapping_flags |= coherent ?
1200 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1201 				if (node->adev->gmc.xgmi.connected_to_cpu)
1202 					snoop = true;
1203 			} else {
1204 				mapping_flags |= coherent ?
1205 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1206 				if (svm_nodes_in_same_hive(node, bo_node))
1207 					snoop = true;
1208 			}
1209 		} else {
1210 			mapping_flags |= coherent ?
1211 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1212 		}
1213 		break;
1214 	case IP_VERSION(9, 4, 3):
1215 	case IP_VERSION(9, 4, 4):
1216 		if (ext_coherent)
1217 			mtype_local = node->adev->rev_id ? AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_UC;
1218 		else
1219 			mtype_local = amdgpu_mtype_local == 1 ? AMDGPU_VM_MTYPE_NC :
1220 				amdgpu_mtype_local == 2 ? AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1221 		snoop = true;
1222 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1223 			/* local HBM region close to partition */
1224 			if (bo_node->adev == node->adev &&
1225 			    (!bo_node->xcp || !node->xcp || bo_node->xcp->mem_id == node->xcp->mem_id))
1226 				mapping_flags |= mtype_local;
1227 			/* local HBM region far from partition or remote XGMI GPU
1228 			 * with regular system scope coherence
1229 			 */
1230 			else if (svm_nodes_in_same_hive(bo_node, node) && !ext_coherent)
1231 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1232 			/* PCIe P2P or extended system scope coherence */
1233 			else
1234 				mapping_flags |= AMDGPU_VM_MTYPE_UC;
1235 		/* system memory accessed by the APU */
1236 		} else if (node->adev->flags & AMD_IS_APU) {
1237 			/* On NUMA systems, locality is determined per-page
1238 			 * in amdgpu_gmc_override_vm_pte_flags
1239 			 */
1240 			if (num_possible_nodes() <= 1)
1241 				mapping_flags |= mtype_local;
1242 			else
1243 				mapping_flags |= ext_coherent ? AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1244 		/* system memory accessed by the dGPU */
1245 		} else {
1246 			mapping_flags |= AMDGPU_VM_MTYPE_UC;
1247 		}
1248 		break;
1249 	case IP_VERSION(12, 0, 0):
1250 	case IP_VERSION(12, 0, 1):
1251 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1252 			if (bo_node != node)
1253 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1254 		} else {
1255 			mapping_flags |= coherent ?
1256 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1257 		}
1258 		break;
1259 	default:
1260 		mapping_flags |= coherent ?
1261 			AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1262 	}
1263 
1264 	mapping_flags |= AMDGPU_VM_PAGE_READABLE | AMDGPU_VM_PAGE_WRITEABLE;
1265 
1266 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_RO)
1267 		mapping_flags &= ~AMDGPU_VM_PAGE_WRITEABLE;
1268 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_EXEC)
1269 		mapping_flags |= AMDGPU_VM_PAGE_EXECUTABLE;
1270 
1271 	pte_flags = AMDGPU_PTE_VALID;
1272 	pte_flags |= (domain == SVM_RANGE_VRAM_DOMAIN) ? 0 : AMDGPU_PTE_SYSTEM;
1273 	pte_flags |= snoop ? AMDGPU_PTE_SNOOPED : 0;
1274 	if (KFD_GC_VERSION(node) >= IP_VERSION(12, 0, 0))
1275 		pte_flags |= AMDGPU_PTE_IS_PTE;
1276 
1277 	pte_flags |= amdgpu_gem_va_map_flags(node->adev, mapping_flags);
1278 	return pte_flags;
1279 }
1280 
1281 static int
1282 svm_range_unmap_from_gpu(struct amdgpu_device *adev, struct amdgpu_vm *vm,
1283 			 uint64_t start, uint64_t last,
1284 			 struct dma_fence **fence)
1285 {
1286 	uint64_t init_pte_value = 0;
1287 
1288 	pr_debug("[0x%llx 0x%llx]\n", start, last);
1289 
1290 	return amdgpu_vm_update_range(adev, vm, false, true, true, false, NULL, start,
1291 				      last, init_pte_value, 0, 0, NULL, NULL,
1292 				      fence);
1293 }
1294 
1295 static int
1296 svm_range_unmap_from_gpus(struct svm_range *prange, unsigned long start,
1297 			  unsigned long last, uint32_t trigger)
1298 {
1299 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1300 	struct kfd_process_device *pdd;
1301 	struct dma_fence *fence = NULL;
1302 	struct kfd_process *p;
1303 	uint32_t gpuidx;
1304 	int r = 0;
1305 
1306 	if (!prange->mapped_to_gpu) {
1307 		pr_debug("prange 0x%p [0x%lx 0x%lx] not mapped to GPU\n",
1308 			 prange, prange->start, prange->last);
1309 		return 0;
1310 	}
1311 
1312 	if (prange->start == start && prange->last == last) {
1313 		pr_debug("unmap svms 0x%p prange 0x%p\n", prange->svms, prange);
1314 		prange->mapped_to_gpu = false;
1315 	}
1316 
1317 	bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
1318 		  MAX_GPU_INSTANCE);
1319 	p = container_of(prange->svms, struct kfd_process, svms);
1320 
1321 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1322 		pr_debug("unmap from gpu idx 0x%x\n", gpuidx);
1323 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1324 		if (!pdd) {
1325 			pr_debug("failed to find device idx %d\n", gpuidx);
1326 			return -EINVAL;
1327 		}
1328 
1329 		kfd_smi_event_unmap_from_gpu(pdd->dev, p->lead_thread->pid,
1330 					     start, last, trigger);
1331 
1332 		r = svm_range_unmap_from_gpu(pdd->dev->adev,
1333 					     drm_priv_to_vm(pdd->drm_priv),
1334 					     start, last, &fence);
1335 		if (r)
1336 			break;
1337 
1338 		if (fence) {
1339 			r = dma_fence_wait(fence, false);
1340 			dma_fence_put(fence);
1341 			fence = NULL;
1342 			if (r)
1343 				break;
1344 		}
1345 		kfd_flush_tlb(pdd, TLB_FLUSH_HEAVYWEIGHT);
1346 	}
1347 
1348 	return r;
1349 }
1350 
1351 static int
1352 svm_range_map_to_gpu(struct kfd_process_device *pdd, struct svm_range *prange,
1353 		     unsigned long offset, unsigned long npages, bool readonly,
1354 		     dma_addr_t *dma_addr, struct amdgpu_device *bo_adev,
1355 		     struct dma_fence **fence, bool flush_tlb)
1356 {
1357 	struct amdgpu_device *adev = pdd->dev->adev;
1358 	struct amdgpu_vm *vm = drm_priv_to_vm(pdd->drm_priv);
1359 	uint64_t pte_flags;
1360 	unsigned long last_start;
1361 	int last_domain;
1362 	int r = 0;
1363 	int64_t i, j;
1364 
1365 	last_start = prange->start + offset;
1366 
1367 	pr_debug("svms 0x%p [0x%lx 0x%lx] readonly %d\n", prange->svms,
1368 		 last_start, last_start + npages - 1, readonly);
1369 
1370 	for (i = offset; i < offset + npages; i++) {
1371 		last_domain = dma_addr[i] & SVM_RANGE_VRAM_DOMAIN;
1372 		dma_addr[i] &= ~SVM_RANGE_VRAM_DOMAIN;
1373 
1374 		/* Collect all pages in the same address range and memory domain
1375 		 * that can be mapped with a single call to update mapping.
1376 		 */
1377 		if (i < offset + npages - 1 &&
1378 		    last_domain == (dma_addr[i + 1] & SVM_RANGE_VRAM_DOMAIN))
1379 			continue;
1380 
1381 		pr_debug("Mapping range [0x%lx 0x%llx] on domain: %s\n",
1382 			 last_start, prange->start + i, last_domain ? "GPU" : "CPU");
1383 
1384 		pte_flags = svm_range_get_pte_flags(pdd->dev, prange, last_domain);
1385 		if (readonly)
1386 			pte_flags &= ~AMDGPU_PTE_WRITEABLE;
1387 
1388 		pr_debug("svms 0x%p map [0x%lx 0x%llx] vram %d PTE 0x%llx\n",
1389 			 prange->svms, last_start, prange->start + i,
1390 			 (last_domain == SVM_RANGE_VRAM_DOMAIN) ? 1 : 0,
1391 			 pte_flags);
1392 
1393 		/* For dGPU mode, we use same vm_manager to allocate VRAM for
1394 		 * different memory partition based on fpfn/lpfn, we should use
1395 		 * same vm_manager.vram_base_offset regardless memory partition.
1396 		 */
1397 		r = amdgpu_vm_update_range(adev, vm, false, false, flush_tlb, true,
1398 					   NULL, last_start, prange->start + i,
1399 					   pte_flags,
1400 					   (last_start - prange->start) << PAGE_SHIFT,
1401 					   bo_adev ? bo_adev->vm_manager.vram_base_offset : 0,
1402 					   NULL, dma_addr, &vm->last_update);
1403 
1404 		for (j = last_start - prange->start; j <= i; j++)
1405 			dma_addr[j] |= last_domain;
1406 
1407 		if (r) {
1408 			pr_debug("failed %d to map to gpu 0x%lx\n", r, prange->start);
1409 			goto out;
1410 		}
1411 		last_start = prange->start + i + 1;
1412 	}
1413 
1414 	r = amdgpu_vm_update_pdes(adev, vm, false);
1415 	if (r) {
1416 		pr_debug("failed %d to update directories 0x%lx\n", r,
1417 			 prange->start);
1418 		goto out;
1419 	}
1420 
1421 	if (fence)
1422 		*fence = dma_fence_get(vm->last_update);
1423 
1424 out:
1425 	return r;
1426 }
1427 
1428 static int
1429 svm_range_map_to_gpus(struct svm_range *prange, unsigned long offset,
1430 		      unsigned long npages, bool readonly,
1431 		      unsigned long *bitmap, bool wait, bool flush_tlb)
1432 {
1433 	struct kfd_process_device *pdd;
1434 	struct amdgpu_device *bo_adev = NULL;
1435 	struct kfd_process *p;
1436 	struct dma_fence *fence = NULL;
1437 	uint32_t gpuidx;
1438 	int r = 0;
1439 
1440 	if (prange->svm_bo && prange->ttm_res)
1441 		bo_adev = prange->svm_bo->node->adev;
1442 
1443 	p = container_of(prange->svms, struct kfd_process, svms);
1444 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1445 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
1446 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1447 		if (!pdd) {
1448 			pr_debug("failed to find device idx %d\n", gpuidx);
1449 			return -EINVAL;
1450 		}
1451 
1452 		pdd = kfd_bind_process_to_device(pdd->dev, p);
1453 		if (IS_ERR(pdd))
1454 			return -EINVAL;
1455 
1456 		if (bo_adev && pdd->dev->adev != bo_adev &&
1457 		    !amdgpu_xgmi_same_hive(pdd->dev->adev, bo_adev)) {
1458 			pr_debug("cannot map to device idx %d\n", gpuidx);
1459 			continue;
1460 		}
1461 
1462 		r = svm_range_map_to_gpu(pdd, prange, offset, npages, readonly,
1463 					 prange->dma_addr[gpuidx],
1464 					 bo_adev, wait ? &fence : NULL,
1465 					 flush_tlb);
1466 		if (r)
1467 			break;
1468 
1469 		if (fence) {
1470 			r = dma_fence_wait(fence, false);
1471 			dma_fence_put(fence);
1472 			fence = NULL;
1473 			if (r) {
1474 				pr_debug("failed %d to dma fence wait\n", r);
1475 				break;
1476 			}
1477 		}
1478 
1479 		kfd_flush_tlb(pdd, TLB_FLUSH_LEGACY);
1480 	}
1481 
1482 	return r;
1483 }
1484 
1485 struct svm_validate_context {
1486 	struct kfd_process *process;
1487 	struct svm_range *prange;
1488 	bool intr;
1489 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1490 	struct drm_exec exec;
1491 };
1492 
1493 static int svm_range_reserve_bos(struct svm_validate_context *ctx, bool intr)
1494 {
1495 	struct kfd_process_device *pdd;
1496 	struct amdgpu_vm *vm;
1497 	uint32_t gpuidx;
1498 	int r;
1499 
1500 	drm_exec_init(&ctx->exec, intr ? DRM_EXEC_INTERRUPTIBLE_WAIT: 0, 0);
1501 	drm_exec_until_all_locked(&ctx->exec) {
1502 		for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1503 			pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1504 			if (!pdd) {
1505 				pr_debug("failed to find device idx %d\n", gpuidx);
1506 				r = -EINVAL;
1507 				goto unreserve_out;
1508 			}
1509 			vm = drm_priv_to_vm(pdd->drm_priv);
1510 
1511 			r = amdgpu_vm_lock_pd(vm, &ctx->exec, 2);
1512 			drm_exec_retry_on_contention(&ctx->exec);
1513 			if (unlikely(r)) {
1514 				pr_debug("failed %d to reserve bo\n", r);
1515 				goto unreserve_out;
1516 			}
1517 		}
1518 	}
1519 
1520 	for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1521 		pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1522 		if (!pdd) {
1523 			pr_debug("failed to find device idx %d\n", gpuidx);
1524 			r = -EINVAL;
1525 			goto unreserve_out;
1526 		}
1527 
1528 		r = amdgpu_vm_validate(pdd->dev->adev,
1529 				       drm_priv_to_vm(pdd->drm_priv), NULL,
1530 				       svm_range_bo_validate, NULL);
1531 		if (r) {
1532 			pr_debug("failed %d validate pt bos\n", r);
1533 			goto unreserve_out;
1534 		}
1535 	}
1536 
1537 	return 0;
1538 
1539 unreserve_out:
1540 	drm_exec_fini(&ctx->exec);
1541 	return r;
1542 }
1543 
1544 static void svm_range_unreserve_bos(struct svm_validate_context *ctx)
1545 {
1546 	drm_exec_fini(&ctx->exec);
1547 }
1548 
1549 static void *kfd_svm_page_owner(struct kfd_process *p, int32_t gpuidx)
1550 {
1551 	struct kfd_process_device *pdd;
1552 
1553 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1554 	if (!pdd)
1555 		return NULL;
1556 
1557 	return SVM_ADEV_PGMAP_OWNER(pdd->dev->adev);
1558 }
1559 
1560 /*
1561  * Validation+GPU mapping with concurrent invalidation (MMU notifiers)
1562  *
1563  * To prevent concurrent destruction or change of range attributes, the
1564  * svm_read_lock must be held. The caller must not hold the svm_write_lock
1565  * because that would block concurrent evictions and lead to deadlocks. To
1566  * serialize concurrent migrations or validations of the same range, the
1567  * prange->migrate_mutex must be held.
1568  *
1569  * For VRAM ranges, the SVM BO must be allocated and valid (protected by its
1570  * eviction fence.
1571  *
1572  * The following sequence ensures race-free validation and GPU mapping:
1573  *
1574  * 1. Reserve page table (and SVM BO if range is in VRAM)
1575  * 2. hmm_range_fault to get page addresses (if system memory)
1576  * 3. DMA-map pages (if system memory)
1577  * 4-a. Take notifier lock
1578  * 4-b. Check that pages still valid (mmu_interval_read_retry)
1579  * 4-c. Check that the range was not split or otherwise invalidated
1580  * 4-d. Update GPU page table
1581  * 4.e. Release notifier lock
1582  * 5. Release page table (and SVM BO) reservation
1583  */
1584 static int svm_range_validate_and_map(struct mm_struct *mm,
1585 				      unsigned long map_start, unsigned long map_last,
1586 				      struct svm_range *prange, int32_t gpuidx,
1587 				      bool intr, bool wait, bool flush_tlb)
1588 {
1589 	struct svm_validate_context *ctx;
1590 	unsigned long start, end, addr;
1591 	struct kfd_process *p;
1592 	void *owner;
1593 	int32_t idx;
1594 	int r = 0;
1595 
1596 	ctx = kzalloc(sizeof(struct svm_validate_context), GFP_KERNEL);
1597 	if (!ctx)
1598 		return -ENOMEM;
1599 	ctx->process = container_of(prange->svms, struct kfd_process, svms);
1600 	ctx->prange = prange;
1601 	ctx->intr = intr;
1602 
1603 	if (gpuidx < MAX_GPU_INSTANCE) {
1604 		bitmap_zero(ctx->bitmap, MAX_GPU_INSTANCE);
1605 		bitmap_set(ctx->bitmap, gpuidx, 1);
1606 	} else if (ctx->process->xnack_enabled) {
1607 		bitmap_copy(ctx->bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
1608 
1609 		/* If prefetch range to GPU, or GPU retry fault migrate range to
1610 		 * GPU, which has ACCESS attribute to the range, create mapping
1611 		 * on that GPU.
1612 		 */
1613 		if (prange->actual_loc) {
1614 			gpuidx = kfd_process_gpuidx_from_gpuid(ctx->process,
1615 							prange->actual_loc);
1616 			if (gpuidx < 0) {
1617 				WARN_ONCE(1, "failed get device by id 0x%x\n",
1618 					 prange->actual_loc);
1619 				r = -EINVAL;
1620 				goto free_ctx;
1621 			}
1622 			if (test_bit(gpuidx, prange->bitmap_access))
1623 				bitmap_set(ctx->bitmap, gpuidx, 1);
1624 		}
1625 
1626 		/*
1627 		 * If prange is already mapped or with always mapped flag,
1628 		 * update mapping on GPUs with ACCESS attribute
1629 		 */
1630 		if (bitmap_empty(ctx->bitmap, MAX_GPU_INSTANCE)) {
1631 			if (prange->mapped_to_gpu ||
1632 			    prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)
1633 				bitmap_copy(ctx->bitmap, prange->bitmap_access, MAX_GPU_INSTANCE);
1634 		}
1635 	} else {
1636 		bitmap_or(ctx->bitmap, prange->bitmap_access,
1637 			  prange->bitmap_aip, MAX_GPU_INSTANCE);
1638 	}
1639 
1640 	if (bitmap_empty(ctx->bitmap, MAX_GPU_INSTANCE)) {
1641 		r = 0;
1642 		goto free_ctx;
1643 	}
1644 
1645 	if (prange->actual_loc && !prange->ttm_res) {
1646 		/* This should never happen. actual_loc gets set by
1647 		 * svm_migrate_ram_to_vram after allocating a BO.
1648 		 */
1649 		WARN_ONCE(1, "VRAM BO missing during validation\n");
1650 		r = -EINVAL;
1651 		goto free_ctx;
1652 	}
1653 
1654 	r = svm_range_reserve_bos(ctx, intr);
1655 	if (r)
1656 		goto free_ctx;
1657 
1658 	p = container_of(prange->svms, struct kfd_process, svms);
1659 	owner = kfd_svm_page_owner(p, find_first_bit(ctx->bitmap,
1660 						MAX_GPU_INSTANCE));
1661 	for_each_set_bit(idx, ctx->bitmap, MAX_GPU_INSTANCE) {
1662 		if (kfd_svm_page_owner(p, idx) != owner) {
1663 			owner = NULL;
1664 			break;
1665 		}
1666 	}
1667 
1668 	start = map_start << PAGE_SHIFT;
1669 	end = (map_last + 1) << PAGE_SHIFT;
1670 	for (addr = start; !r && addr < end; ) {
1671 		struct hmm_range *hmm_range = NULL;
1672 		unsigned long map_start_vma;
1673 		unsigned long map_last_vma;
1674 		struct vm_area_struct *vma;
1675 		unsigned long next = 0;
1676 		unsigned long offset;
1677 		unsigned long npages;
1678 		bool readonly;
1679 
1680 		vma = vma_lookup(mm, addr);
1681 		if (vma) {
1682 			readonly = !(vma->vm_flags & VM_WRITE);
1683 
1684 			next = min(vma->vm_end, end);
1685 			npages = (next - addr) >> PAGE_SHIFT;
1686 			WRITE_ONCE(p->svms.faulting_task, current);
1687 			r = amdgpu_hmm_range_get_pages(&prange->notifier, addr, npages,
1688 						       readonly, owner, NULL,
1689 						       &hmm_range);
1690 			WRITE_ONCE(p->svms.faulting_task, NULL);
1691 			if (r)
1692 				pr_debug("failed %d to get svm range pages\n", r);
1693 		} else {
1694 			r = -EFAULT;
1695 		}
1696 
1697 		if (!r) {
1698 			offset = (addr >> PAGE_SHIFT) - prange->start;
1699 			r = svm_range_dma_map(prange, ctx->bitmap, offset, npages,
1700 					      hmm_range->hmm_pfns);
1701 			if (r)
1702 				pr_debug("failed %d to dma map range\n", r);
1703 		}
1704 
1705 		svm_range_lock(prange);
1706 
1707 		/* Free backing memory of hmm_range if it was initialized
1708 		 * Overrride return value to TRY AGAIN only if prior returns
1709 		 * were successful
1710 		 */
1711 		if (hmm_range && amdgpu_hmm_range_get_pages_done(hmm_range) && !r) {
1712 			pr_debug("hmm update the range, need validate again\n");
1713 			r = -EAGAIN;
1714 		}
1715 
1716 		if (!r && !list_empty(&prange->child_list)) {
1717 			pr_debug("range split by unmap in parallel, validate again\n");
1718 			r = -EAGAIN;
1719 		}
1720 
1721 		if (!r) {
1722 			map_start_vma = max(map_start, prange->start + offset);
1723 			map_last_vma = min(map_last, prange->start + offset + npages - 1);
1724 			if (map_start_vma <= map_last_vma) {
1725 				offset = map_start_vma - prange->start;
1726 				npages = map_last_vma - map_start_vma + 1;
1727 				r = svm_range_map_to_gpus(prange, offset, npages, readonly,
1728 							  ctx->bitmap, wait, flush_tlb);
1729 			}
1730 		}
1731 
1732 		if (!r && next == end)
1733 			prange->mapped_to_gpu = true;
1734 
1735 		svm_range_unlock(prange);
1736 
1737 		addr = next;
1738 	}
1739 
1740 	svm_range_unreserve_bos(ctx);
1741 	if (!r)
1742 		prange->validate_timestamp = ktime_get_boottime();
1743 
1744 free_ctx:
1745 	kfree(ctx);
1746 
1747 	return r;
1748 }
1749 
1750 /**
1751  * svm_range_list_lock_and_flush_work - flush pending deferred work
1752  *
1753  * @svms: the svm range list
1754  * @mm: the mm structure
1755  *
1756  * Context: Returns with mmap write lock held, pending deferred work flushed
1757  *
1758  */
1759 void
1760 svm_range_list_lock_and_flush_work(struct svm_range_list *svms,
1761 				   struct mm_struct *mm)
1762 {
1763 retry_flush_work:
1764 	flush_work(&svms->deferred_list_work);
1765 	mmap_write_lock(mm);
1766 
1767 	if (list_empty(&svms->deferred_range_list))
1768 		return;
1769 	mmap_write_unlock(mm);
1770 	pr_debug("retry flush\n");
1771 	goto retry_flush_work;
1772 }
1773 
1774 static void svm_range_restore_work(struct work_struct *work)
1775 {
1776 	struct delayed_work *dwork = to_delayed_work(work);
1777 	struct amdkfd_process_info *process_info;
1778 	struct svm_range_list *svms;
1779 	struct svm_range *prange;
1780 	struct kfd_process *p;
1781 	struct mm_struct *mm;
1782 	int evicted_ranges;
1783 	int invalid;
1784 	int r;
1785 
1786 	svms = container_of(dwork, struct svm_range_list, restore_work);
1787 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1788 	if (!evicted_ranges)
1789 		return;
1790 
1791 	pr_debug("restore svm ranges\n");
1792 
1793 	p = container_of(svms, struct kfd_process, svms);
1794 	process_info = p->kgd_process_info;
1795 
1796 	/* Keep mm reference when svm_range_validate_and_map ranges */
1797 	mm = get_task_mm(p->lead_thread);
1798 	if (!mm) {
1799 		pr_debug("svms 0x%p process mm gone\n", svms);
1800 		return;
1801 	}
1802 
1803 	mutex_lock(&process_info->lock);
1804 	svm_range_list_lock_and_flush_work(svms, mm);
1805 	mutex_lock(&svms->lock);
1806 
1807 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1808 
1809 	list_for_each_entry(prange, &svms->list, list) {
1810 		invalid = atomic_read(&prange->invalid);
1811 		if (!invalid)
1812 			continue;
1813 
1814 		pr_debug("restoring svms 0x%p prange 0x%p [0x%lx %lx] inv %d\n",
1815 			 prange->svms, prange, prange->start, prange->last,
1816 			 invalid);
1817 
1818 		/*
1819 		 * If range is migrating, wait for migration is done.
1820 		 */
1821 		mutex_lock(&prange->migrate_mutex);
1822 
1823 		r = svm_range_validate_and_map(mm, prange->start, prange->last, prange,
1824 					       MAX_GPU_INSTANCE, false, true, false);
1825 		if (r)
1826 			pr_debug("failed %d to map 0x%lx to gpus\n", r,
1827 				 prange->start);
1828 
1829 		mutex_unlock(&prange->migrate_mutex);
1830 		if (r)
1831 			goto out_reschedule;
1832 
1833 		if (atomic_cmpxchg(&prange->invalid, invalid, 0) != invalid)
1834 			goto out_reschedule;
1835 	}
1836 
1837 	if (atomic_cmpxchg(&svms->evicted_ranges, evicted_ranges, 0) !=
1838 	    evicted_ranges)
1839 		goto out_reschedule;
1840 
1841 	evicted_ranges = 0;
1842 
1843 	r = kgd2kfd_resume_mm(mm);
1844 	if (r) {
1845 		/* No recovery from this failure. Probably the CP is
1846 		 * hanging. No point trying again.
1847 		 */
1848 		pr_debug("failed %d to resume KFD\n", r);
1849 	}
1850 
1851 	pr_debug("restore svm ranges successfully\n");
1852 
1853 out_reschedule:
1854 	mutex_unlock(&svms->lock);
1855 	mmap_write_unlock(mm);
1856 	mutex_unlock(&process_info->lock);
1857 
1858 	/* If validation failed, reschedule another attempt */
1859 	if (evicted_ranges) {
1860 		pr_debug("reschedule to restore svm range\n");
1861 		queue_delayed_work(system_freezable_wq, &svms->restore_work,
1862 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1863 
1864 		kfd_smi_event_queue_restore_rescheduled(mm);
1865 	}
1866 	mmput(mm);
1867 }
1868 
1869 /**
1870  * svm_range_evict - evict svm range
1871  * @prange: svm range structure
1872  * @mm: current process mm_struct
1873  * @start: starting process queue number
1874  * @last: last process queue number
1875  * @event: mmu notifier event when range is evicted or migrated
1876  *
1877  * Stop all queues of the process to ensure GPU doesn't access the memory, then
1878  * return to let CPU evict the buffer and proceed CPU pagetable update.
1879  *
1880  * Don't need use lock to sync cpu pagetable invalidation with GPU execution.
1881  * If invalidation happens while restore work is running, restore work will
1882  * restart to ensure to get the latest CPU pages mapping to GPU, then start
1883  * the queues.
1884  */
1885 static int
1886 svm_range_evict(struct svm_range *prange, struct mm_struct *mm,
1887 		unsigned long start, unsigned long last,
1888 		enum mmu_notifier_event event)
1889 {
1890 	struct svm_range_list *svms = prange->svms;
1891 	struct svm_range *pchild;
1892 	struct kfd_process *p;
1893 	int r = 0;
1894 
1895 	p = container_of(svms, struct kfd_process, svms);
1896 
1897 	pr_debug("invalidate svms 0x%p prange [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
1898 		 svms, prange->start, prange->last, start, last);
1899 
1900 	if (!p->xnack_enabled ||
1901 	    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) {
1902 		int evicted_ranges;
1903 		bool mapped = prange->mapped_to_gpu;
1904 
1905 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1906 			if (!pchild->mapped_to_gpu)
1907 				continue;
1908 			mapped = true;
1909 			mutex_lock_nested(&pchild->lock, 1);
1910 			if (pchild->start <= last && pchild->last >= start) {
1911 				pr_debug("increment pchild invalid [0x%lx 0x%lx]\n",
1912 					 pchild->start, pchild->last);
1913 				atomic_inc(&pchild->invalid);
1914 			}
1915 			mutex_unlock(&pchild->lock);
1916 		}
1917 
1918 		if (!mapped)
1919 			return r;
1920 
1921 		if (prange->start <= last && prange->last >= start)
1922 			atomic_inc(&prange->invalid);
1923 
1924 		evicted_ranges = atomic_inc_return(&svms->evicted_ranges);
1925 		if (evicted_ranges != 1)
1926 			return r;
1927 
1928 		pr_debug("evicting svms 0x%p range [0x%lx 0x%lx]\n",
1929 			 prange->svms, prange->start, prange->last);
1930 
1931 		/* First eviction, stop the queues */
1932 		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_SVM);
1933 		if (r)
1934 			pr_debug("failed to quiesce KFD\n");
1935 
1936 		pr_debug("schedule to restore svm %p ranges\n", svms);
1937 		queue_delayed_work(system_freezable_wq, &svms->restore_work,
1938 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1939 	} else {
1940 		unsigned long s, l;
1941 		uint32_t trigger;
1942 
1943 		if (event == MMU_NOTIFY_MIGRATE)
1944 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY_MIGRATE;
1945 		else
1946 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY;
1947 
1948 		pr_debug("invalidate unmap svms 0x%p [0x%lx 0x%lx] from GPUs\n",
1949 			 prange->svms, start, last);
1950 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1951 			mutex_lock_nested(&pchild->lock, 1);
1952 			s = max(start, pchild->start);
1953 			l = min(last, pchild->last);
1954 			if (l >= s)
1955 				svm_range_unmap_from_gpus(pchild, s, l, trigger);
1956 			mutex_unlock(&pchild->lock);
1957 		}
1958 		s = max(start, prange->start);
1959 		l = min(last, prange->last);
1960 		if (l >= s)
1961 			svm_range_unmap_from_gpus(prange, s, l, trigger);
1962 	}
1963 
1964 	return r;
1965 }
1966 
1967 static struct svm_range *svm_range_clone(struct svm_range *old)
1968 {
1969 	struct svm_range *new;
1970 
1971 	new = svm_range_new(old->svms, old->start, old->last, false);
1972 	if (!new)
1973 		return NULL;
1974 	if (svm_range_copy_dma_addrs(new, old)) {
1975 		svm_range_free(new, false);
1976 		return NULL;
1977 	}
1978 	if (old->svm_bo) {
1979 		new->ttm_res = old->ttm_res;
1980 		new->offset = old->offset;
1981 		new->svm_bo = svm_range_bo_ref(old->svm_bo);
1982 		spin_lock(&new->svm_bo->list_lock);
1983 		list_add(&new->svm_bo_list, &new->svm_bo->range_list);
1984 		spin_unlock(&new->svm_bo->list_lock);
1985 	}
1986 	new->flags = old->flags;
1987 	new->preferred_loc = old->preferred_loc;
1988 	new->prefetch_loc = old->prefetch_loc;
1989 	new->actual_loc = old->actual_loc;
1990 	new->granularity = old->granularity;
1991 	new->mapped_to_gpu = old->mapped_to_gpu;
1992 	new->vram_pages = old->vram_pages;
1993 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
1994 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
1995 
1996 	return new;
1997 }
1998 
1999 void svm_range_set_max_pages(struct amdgpu_device *adev)
2000 {
2001 	uint64_t max_pages;
2002 	uint64_t pages, _pages;
2003 	uint64_t min_pages = 0;
2004 	int i, id;
2005 
2006 	for (i = 0; i < adev->kfd.dev->num_nodes; i++) {
2007 		if (adev->kfd.dev->nodes[i]->xcp)
2008 			id = adev->kfd.dev->nodes[i]->xcp->id;
2009 		else
2010 			id = -1;
2011 		pages = KFD_XCP_MEMORY_SIZE(adev, id) >> 17;
2012 		pages = clamp(pages, 1ULL << 9, 1ULL << 18);
2013 		pages = rounddown_pow_of_two(pages);
2014 		min_pages = min_not_zero(min_pages, pages);
2015 	}
2016 
2017 	do {
2018 		max_pages = READ_ONCE(max_svm_range_pages);
2019 		_pages = min_not_zero(max_pages, min_pages);
2020 	} while (cmpxchg(&max_svm_range_pages, max_pages, _pages) != max_pages);
2021 }
2022 
2023 static int
2024 svm_range_split_new(struct svm_range_list *svms, uint64_t start, uint64_t last,
2025 		    uint64_t max_pages, struct list_head *insert_list,
2026 		    struct list_head *update_list)
2027 {
2028 	struct svm_range *prange;
2029 	uint64_t l;
2030 
2031 	pr_debug("max_svm_range_pages 0x%llx adding [0x%llx 0x%llx]\n",
2032 		 max_pages, start, last);
2033 
2034 	while (last >= start) {
2035 		l = min(last, ALIGN_DOWN(start + max_pages, max_pages) - 1);
2036 
2037 		prange = svm_range_new(svms, start, l, true);
2038 		if (!prange)
2039 			return -ENOMEM;
2040 		list_add(&prange->list, insert_list);
2041 		list_add(&prange->update_list, update_list);
2042 
2043 		start = l + 1;
2044 	}
2045 	return 0;
2046 }
2047 
2048 /**
2049  * svm_range_add - add svm range and handle overlap
2050  * @p: the range add to this process svms
2051  * @start: page size aligned
2052  * @size: page size aligned
2053  * @nattr: number of attributes
2054  * @attrs: array of attributes
2055  * @update_list: output, the ranges need validate and update GPU mapping
2056  * @insert_list: output, the ranges need insert to svms
2057  * @remove_list: output, the ranges are replaced and need remove from svms
2058  * @remap_list: output, remap unaligned svm ranges
2059  *
2060  * Check if the virtual address range has overlap with any existing ranges,
2061  * split partly overlapping ranges and add new ranges in the gaps. All changes
2062  * should be applied to the range_list and interval tree transactionally. If
2063  * any range split or allocation fails, the entire update fails. Therefore any
2064  * existing overlapping svm_ranges are cloned and the original svm_ranges left
2065  * unchanged.
2066  *
2067  * If the transaction succeeds, the caller can update and insert clones and
2068  * new ranges, then free the originals.
2069  *
2070  * Otherwise the caller can free the clones and new ranges, while the old
2071  * svm_ranges remain unchanged.
2072  *
2073  * Context: Process context, caller must hold svms->lock
2074  *
2075  * Return:
2076  * 0 - OK, otherwise error code
2077  */
2078 static int
2079 svm_range_add(struct kfd_process *p, uint64_t start, uint64_t size,
2080 	      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
2081 	      struct list_head *update_list, struct list_head *insert_list,
2082 	      struct list_head *remove_list, struct list_head *remap_list)
2083 {
2084 	unsigned long last = start + size - 1UL;
2085 	struct svm_range_list *svms = &p->svms;
2086 	struct interval_tree_node *node;
2087 	struct svm_range *prange;
2088 	struct svm_range *tmp;
2089 	struct list_head new_list;
2090 	int r = 0;
2091 
2092 	pr_debug("svms 0x%p [0x%llx 0x%lx]\n", &p->svms, start, last);
2093 
2094 	INIT_LIST_HEAD(update_list);
2095 	INIT_LIST_HEAD(insert_list);
2096 	INIT_LIST_HEAD(remove_list);
2097 	INIT_LIST_HEAD(&new_list);
2098 	INIT_LIST_HEAD(remap_list);
2099 
2100 	node = interval_tree_iter_first(&svms->objects, start, last);
2101 	while (node) {
2102 		struct interval_tree_node *next;
2103 		unsigned long next_start;
2104 
2105 		pr_debug("found overlap node [0x%lx 0x%lx]\n", node->start,
2106 			 node->last);
2107 
2108 		prange = container_of(node, struct svm_range, it_node);
2109 		next = interval_tree_iter_next(node, start, last);
2110 		next_start = min(node->last, last) + 1;
2111 
2112 		if (svm_range_is_same_attrs(p, prange, nattr, attrs) &&
2113 		    prange->mapped_to_gpu) {
2114 			/* nothing to do */
2115 		} else if (node->start < start || node->last > last) {
2116 			/* node intersects the update range and its attributes
2117 			 * will change. Clone and split it, apply updates only
2118 			 * to the overlapping part
2119 			 */
2120 			struct svm_range *old = prange;
2121 
2122 			prange = svm_range_clone(old);
2123 			if (!prange) {
2124 				r = -ENOMEM;
2125 				goto out;
2126 			}
2127 
2128 			list_add(&old->update_list, remove_list);
2129 			list_add(&prange->list, insert_list);
2130 			list_add(&prange->update_list, update_list);
2131 
2132 			if (node->start < start) {
2133 				pr_debug("change old range start\n");
2134 				r = svm_range_split_head(prange, start,
2135 							 insert_list, remap_list);
2136 				if (r)
2137 					goto out;
2138 			}
2139 			if (node->last > last) {
2140 				pr_debug("change old range last\n");
2141 				r = svm_range_split_tail(prange, last,
2142 							 insert_list, remap_list);
2143 				if (r)
2144 					goto out;
2145 			}
2146 		} else {
2147 			/* The node is contained within start..last,
2148 			 * just update it
2149 			 */
2150 			list_add(&prange->update_list, update_list);
2151 		}
2152 
2153 		/* insert a new node if needed */
2154 		if (node->start > start) {
2155 			r = svm_range_split_new(svms, start, node->start - 1,
2156 						READ_ONCE(max_svm_range_pages),
2157 						&new_list, update_list);
2158 			if (r)
2159 				goto out;
2160 		}
2161 
2162 		node = next;
2163 		start = next_start;
2164 	}
2165 
2166 	/* add a final range at the end if needed */
2167 	if (start <= last)
2168 		r = svm_range_split_new(svms, start, last,
2169 					READ_ONCE(max_svm_range_pages),
2170 					&new_list, update_list);
2171 
2172 out:
2173 	if (r) {
2174 		list_for_each_entry_safe(prange, tmp, insert_list, list)
2175 			svm_range_free(prange, false);
2176 		list_for_each_entry_safe(prange, tmp, &new_list, list)
2177 			svm_range_free(prange, true);
2178 	} else {
2179 		list_splice(&new_list, insert_list);
2180 	}
2181 
2182 	return r;
2183 }
2184 
2185 static void
2186 svm_range_update_notifier_and_interval_tree(struct mm_struct *mm,
2187 					    struct svm_range *prange)
2188 {
2189 	unsigned long start;
2190 	unsigned long last;
2191 
2192 	start = prange->notifier.interval_tree.start >> PAGE_SHIFT;
2193 	last = prange->notifier.interval_tree.last >> PAGE_SHIFT;
2194 
2195 	if (prange->start == start && prange->last == last)
2196 		return;
2197 
2198 	pr_debug("up notifier 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
2199 		  prange->svms, prange, start, last, prange->start,
2200 		  prange->last);
2201 
2202 	if (start != 0 && last != 0) {
2203 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
2204 		svm_range_remove_notifier(prange);
2205 	}
2206 	prange->it_node.start = prange->start;
2207 	prange->it_node.last = prange->last;
2208 
2209 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
2210 	svm_range_add_notifier_locked(mm, prange);
2211 }
2212 
2213 static void
2214 svm_range_handle_list_op(struct svm_range_list *svms, struct svm_range *prange,
2215 			 struct mm_struct *mm)
2216 {
2217 	switch (prange->work_item.op) {
2218 	case SVM_OP_NULL:
2219 		pr_debug("NULL OP 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2220 			 svms, prange, prange->start, prange->last);
2221 		break;
2222 	case SVM_OP_UNMAP_RANGE:
2223 		pr_debug("remove 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2224 			 svms, prange, prange->start, prange->last);
2225 		svm_range_unlink(prange);
2226 		svm_range_remove_notifier(prange);
2227 		svm_range_free(prange, true);
2228 		break;
2229 	case SVM_OP_UPDATE_RANGE_NOTIFIER:
2230 		pr_debug("update notifier 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2231 			 svms, prange, prange->start, prange->last);
2232 		svm_range_update_notifier_and_interval_tree(mm, prange);
2233 		break;
2234 	case SVM_OP_UPDATE_RANGE_NOTIFIER_AND_MAP:
2235 		pr_debug("update and map 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2236 			 svms, prange, prange->start, prange->last);
2237 		svm_range_update_notifier_and_interval_tree(mm, prange);
2238 		/* TODO: implement deferred validation and mapping */
2239 		break;
2240 	case SVM_OP_ADD_RANGE:
2241 		pr_debug("add 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms, prange,
2242 			 prange->start, prange->last);
2243 		svm_range_add_to_svms(prange);
2244 		svm_range_add_notifier_locked(mm, prange);
2245 		break;
2246 	case SVM_OP_ADD_RANGE_AND_MAP:
2247 		pr_debug("add and map 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms,
2248 			 prange, prange->start, prange->last);
2249 		svm_range_add_to_svms(prange);
2250 		svm_range_add_notifier_locked(mm, prange);
2251 		/* TODO: implement deferred validation and mapping */
2252 		break;
2253 	default:
2254 		WARN_ONCE(1, "Unknown prange 0x%p work op %d\n", prange,
2255 			 prange->work_item.op);
2256 	}
2257 }
2258 
2259 static void svm_range_drain_retry_fault(struct svm_range_list *svms)
2260 {
2261 	struct kfd_process_device *pdd;
2262 	struct kfd_process *p;
2263 	int drain;
2264 	uint32_t i;
2265 
2266 	p = container_of(svms, struct kfd_process, svms);
2267 
2268 restart:
2269 	drain = atomic_read(&svms->drain_pagefaults);
2270 	if (!drain)
2271 		return;
2272 
2273 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2274 		pdd = p->pdds[i];
2275 		if (!pdd)
2276 			continue;
2277 
2278 		pr_debug("drain retry fault gpu %d svms %p\n", i, svms);
2279 
2280 		amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2281 				pdd->dev->adev->irq.retry_cam_enabled ?
2282 				&pdd->dev->adev->irq.ih :
2283 				&pdd->dev->adev->irq.ih1);
2284 
2285 		if (pdd->dev->adev->irq.retry_cam_enabled)
2286 			amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2287 				&pdd->dev->adev->irq.ih_soft);
2288 
2289 
2290 		pr_debug("drain retry fault gpu %d svms 0x%p done\n", i, svms);
2291 	}
2292 	if (atomic_cmpxchg(&svms->drain_pagefaults, drain, 0) != drain)
2293 		goto restart;
2294 }
2295 
2296 static void svm_range_deferred_list_work(struct work_struct *work)
2297 {
2298 	struct svm_range_list *svms;
2299 	struct svm_range *prange;
2300 	struct mm_struct *mm;
2301 
2302 	svms = container_of(work, struct svm_range_list, deferred_list_work);
2303 	pr_debug("enter svms 0x%p\n", svms);
2304 
2305 	spin_lock(&svms->deferred_list_lock);
2306 	while (!list_empty(&svms->deferred_range_list)) {
2307 		prange = list_first_entry(&svms->deferred_range_list,
2308 					  struct svm_range, deferred_list);
2309 		spin_unlock(&svms->deferred_list_lock);
2310 
2311 		pr_debug("prange 0x%p [0x%lx 0x%lx] op %d\n", prange,
2312 			 prange->start, prange->last, prange->work_item.op);
2313 
2314 		mm = prange->work_item.mm;
2315 retry:
2316 		mmap_write_lock(mm);
2317 
2318 		/* Checking for the need to drain retry faults must be inside
2319 		 * mmap write lock to serialize with munmap notifiers.
2320 		 */
2321 		if (unlikely(atomic_read(&svms->drain_pagefaults))) {
2322 			mmap_write_unlock(mm);
2323 			svm_range_drain_retry_fault(svms);
2324 			goto retry;
2325 		}
2326 
2327 		/* Remove from deferred_list must be inside mmap write lock, for
2328 		 * two race cases:
2329 		 * 1. unmap_from_cpu may change work_item.op and add the range
2330 		 *    to deferred_list again, cause use after free bug.
2331 		 * 2. svm_range_list_lock_and_flush_work may hold mmap write
2332 		 *    lock and continue because deferred_list is empty, but
2333 		 *    deferred_list work is actually waiting for mmap lock.
2334 		 */
2335 		spin_lock(&svms->deferred_list_lock);
2336 		list_del_init(&prange->deferred_list);
2337 		spin_unlock(&svms->deferred_list_lock);
2338 
2339 		mutex_lock(&svms->lock);
2340 		mutex_lock(&prange->migrate_mutex);
2341 		while (!list_empty(&prange->child_list)) {
2342 			struct svm_range *pchild;
2343 
2344 			pchild = list_first_entry(&prange->child_list,
2345 						struct svm_range, child_list);
2346 			pr_debug("child prange 0x%p op %d\n", pchild,
2347 				 pchild->work_item.op);
2348 			list_del_init(&pchild->child_list);
2349 			svm_range_handle_list_op(svms, pchild, mm);
2350 		}
2351 		mutex_unlock(&prange->migrate_mutex);
2352 
2353 		svm_range_handle_list_op(svms, prange, mm);
2354 		mutex_unlock(&svms->lock);
2355 		mmap_write_unlock(mm);
2356 
2357 		/* Pairs with mmget in svm_range_add_list_work. If dropping the
2358 		 * last mm refcount, schedule release work to avoid circular locking
2359 		 */
2360 		mmput_async(mm);
2361 
2362 		spin_lock(&svms->deferred_list_lock);
2363 	}
2364 	spin_unlock(&svms->deferred_list_lock);
2365 	pr_debug("exit svms 0x%p\n", svms);
2366 }
2367 
2368 void
2369 svm_range_add_list_work(struct svm_range_list *svms, struct svm_range *prange,
2370 			struct mm_struct *mm, enum svm_work_list_ops op)
2371 {
2372 	spin_lock(&svms->deferred_list_lock);
2373 	/* if prange is on the deferred list */
2374 	if (!list_empty(&prange->deferred_list)) {
2375 		pr_debug("update exist prange 0x%p work op %d\n", prange, op);
2376 		WARN_ONCE(prange->work_item.mm != mm, "unmatch mm\n");
2377 		if (op != SVM_OP_NULL &&
2378 		    prange->work_item.op != SVM_OP_UNMAP_RANGE)
2379 			prange->work_item.op = op;
2380 	} else {
2381 		prange->work_item.op = op;
2382 
2383 		/* Pairs with mmput in deferred_list_work */
2384 		mmget(mm);
2385 		prange->work_item.mm = mm;
2386 		list_add_tail(&prange->deferred_list,
2387 			      &prange->svms->deferred_range_list);
2388 		pr_debug("add prange 0x%p [0x%lx 0x%lx] to work list op %d\n",
2389 			 prange, prange->start, prange->last, op);
2390 	}
2391 	spin_unlock(&svms->deferred_list_lock);
2392 }
2393 
2394 void schedule_deferred_list_work(struct svm_range_list *svms)
2395 {
2396 	spin_lock(&svms->deferred_list_lock);
2397 	if (!list_empty(&svms->deferred_range_list))
2398 		schedule_work(&svms->deferred_list_work);
2399 	spin_unlock(&svms->deferred_list_lock);
2400 }
2401 
2402 static void
2403 svm_range_unmap_split(struct mm_struct *mm, struct svm_range *parent,
2404 		      struct svm_range *prange, unsigned long start,
2405 		      unsigned long last)
2406 {
2407 	struct svm_range *head;
2408 	struct svm_range *tail;
2409 
2410 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2411 		pr_debug("prange 0x%p [0x%lx 0x%lx] is already freed\n", prange,
2412 			 prange->start, prange->last);
2413 		return;
2414 	}
2415 	if (start > prange->last || last < prange->start)
2416 		return;
2417 
2418 	head = tail = prange;
2419 	if (start > prange->start)
2420 		svm_range_split(prange, prange->start, start - 1, &tail);
2421 	if (last < tail->last)
2422 		svm_range_split(tail, last + 1, tail->last, &head);
2423 
2424 	if (head != prange && tail != prange) {
2425 		svm_range_add_child(parent, mm, head, SVM_OP_UNMAP_RANGE);
2426 		svm_range_add_child(parent, mm, tail, SVM_OP_ADD_RANGE);
2427 	} else if (tail != prange) {
2428 		svm_range_add_child(parent, mm, tail, SVM_OP_UNMAP_RANGE);
2429 	} else if (head != prange) {
2430 		svm_range_add_child(parent, mm, head, SVM_OP_UNMAP_RANGE);
2431 	} else if (parent != prange) {
2432 		prange->work_item.op = SVM_OP_UNMAP_RANGE;
2433 	}
2434 }
2435 
2436 static void
2437 svm_range_unmap_from_cpu(struct mm_struct *mm, struct svm_range *prange,
2438 			 unsigned long start, unsigned long last)
2439 {
2440 	uint32_t trigger = KFD_SVM_UNMAP_TRIGGER_UNMAP_FROM_CPU;
2441 	struct svm_range_list *svms;
2442 	struct svm_range *pchild;
2443 	struct kfd_process *p;
2444 	unsigned long s, l;
2445 	bool unmap_parent;
2446 
2447 	p = kfd_lookup_process_by_mm(mm);
2448 	if (!p)
2449 		return;
2450 	svms = &p->svms;
2451 
2452 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n", svms,
2453 		 prange, prange->start, prange->last, start, last);
2454 
2455 	/* Make sure pending page faults are drained in the deferred worker
2456 	 * before the range is freed to avoid straggler interrupts on
2457 	 * unmapped memory causing "phantom faults".
2458 	 */
2459 	atomic_inc(&svms->drain_pagefaults);
2460 
2461 	unmap_parent = start <= prange->start && last >= prange->last;
2462 
2463 	list_for_each_entry(pchild, &prange->child_list, child_list) {
2464 		mutex_lock_nested(&pchild->lock, 1);
2465 		s = max(start, pchild->start);
2466 		l = min(last, pchild->last);
2467 		if (l >= s)
2468 			svm_range_unmap_from_gpus(pchild, s, l, trigger);
2469 		svm_range_unmap_split(mm, prange, pchild, start, last);
2470 		mutex_unlock(&pchild->lock);
2471 	}
2472 	s = max(start, prange->start);
2473 	l = min(last, prange->last);
2474 	if (l >= s)
2475 		svm_range_unmap_from_gpus(prange, s, l, trigger);
2476 	svm_range_unmap_split(mm, prange, prange, start, last);
2477 
2478 	if (unmap_parent)
2479 		svm_range_add_list_work(svms, prange, mm, SVM_OP_UNMAP_RANGE);
2480 	else
2481 		svm_range_add_list_work(svms, prange, mm,
2482 					SVM_OP_UPDATE_RANGE_NOTIFIER);
2483 	schedule_deferred_list_work(svms);
2484 
2485 	kfd_unref_process(p);
2486 }
2487 
2488 /**
2489  * svm_range_cpu_invalidate_pagetables - interval notifier callback
2490  * @mni: mmu_interval_notifier struct
2491  * @range: mmu_notifier_range struct
2492  * @cur_seq: value to pass to mmu_interval_set_seq()
2493  *
2494  * If event is MMU_NOTIFY_UNMAP, this is from CPU unmap range, otherwise, it
2495  * is from migration, or CPU page invalidation callback.
2496  *
2497  * For unmap event, unmap range from GPUs, remove prange from svms in a delayed
2498  * work thread, and split prange if only part of prange is unmapped.
2499  *
2500  * For invalidation event, if GPU retry fault is not enabled, evict the queues,
2501  * then schedule svm_range_restore_work to update GPU mapping and resume queues.
2502  * If GPU retry fault is enabled, unmap the svm range from GPU, retry fault will
2503  * update GPU mapping to recover.
2504  *
2505  * Context: mmap lock, notifier_invalidate_start lock are held
2506  *          for invalidate event, prange lock is held if this is from migration
2507  */
2508 static bool
2509 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
2510 				    const struct mmu_notifier_range *range,
2511 				    unsigned long cur_seq)
2512 {
2513 	struct svm_range *prange;
2514 	unsigned long start;
2515 	unsigned long last;
2516 
2517 	if (range->event == MMU_NOTIFY_RELEASE)
2518 		return true;
2519 	if (!mmget_not_zero(mni->mm))
2520 		return true;
2521 
2522 	start = mni->interval_tree.start;
2523 	last = mni->interval_tree.last;
2524 	start = max(start, range->start) >> PAGE_SHIFT;
2525 	last = min(last, range->end - 1) >> PAGE_SHIFT;
2526 	pr_debug("[0x%lx 0x%lx] range[0x%lx 0x%lx] notifier[0x%lx 0x%lx] %d\n",
2527 		 start, last, range->start >> PAGE_SHIFT,
2528 		 (range->end - 1) >> PAGE_SHIFT,
2529 		 mni->interval_tree.start >> PAGE_SHIFT,
2530 		 mni->interval_tree.last >> PAGE_SHIFT, range->event);
2531 
2532 	prange = container_of(mni, struct svm_range, notifier);
2533 
2534 	svm_range_lock(prange);
2535 	mmu_interval_set_seq(mni, cur_seq);
2536 
2537 	switch (range->event) {
2538 	case MMU_NOTIFY_UNMAP:
2539 		svm_range_unmap_from_cpu(mni->mm, prange, start, last);
2540 		break;
2541 	default:
2542 		svm_range_evict(prange, mni->mm, start, last, range->event);
2543 		break;
2544 	}
2545 
2546 	svm_range_unlock(prange);
2547 	mmput(mni->mm);
2548 
2549 	return true;
2550 }
2551 
2552 /**
2553  * svm_range_from_addr - find svm range from fault address
2554  * @svms: svm range list header
2555  * @addr: address to search range interval tree, in pages
2556  * @parent: parent range if range is on child list
2557  *
2558  * Context: The caller must hold svms->lock
2559  *
2560  * Return: the svm_range found or NULL
2561  */
2562 struct svm_range *
2563 svm_range_from_addr(struct svm_range_list *svms, unsigned long addr,
2564 		    struct svm_range **parent)
2565 {
2566 	struct interval_tree_node *node;
2567 	struct svm_range *prange;
2568 	struct svm_range *pchild;
2569 
2570 	node = interval_tree_iter_first(&svms->objects, addr, addr);
2571 	if (!node)
2572 		return NULL;
2573 
2574 	prange = container_of(node, struct svm_range, it_node);
2575 	pr_debug("address 0x%lx prange [0x%lx 0x%lx] node [0x%lx 0x%lx]\n",
2576 		 addr, prange->start, prange->last, node->start, node->last);
2577 
2578 	if (addr >= prange->start && addr <= prange->last) {
2579 		if (parent)
2580 			*parent = prange;
2581 		return prange;
2582 	}
2583 	list_for_each_entry(pchild, &prange->child_list, child_list)
2584 		if (addr >= pchild->start && addr <= pchild->last) {
2585 			pr_debug("found address 0x%lx pchild [0x%lx 0x%lx]\n",
2586 				 addr, pchild->start, pchild->last);
2587 			if (parent)
2588 				*parent = prange;
2589 			return pchild;
2590 		}
2591 
2592 	return NULL;
2593 }
2594 
2595 /* svm_range_best_restore_location - decide the best fault restore location
2596  * @prange: svm range structure
2597  * @adev: the GPU on which vm fault happened
2598  *
2599  * This is only called when xnack is on, to decide the best location to restore
2600  * the range mapping after GPU vm fault. Caller uses the best location to do
2601  * migration if actual loc is not best location, then update GPU page table
2602  * mapping to the best location.
2603  *
2604  * If the preferred loc is accessible by faulting GPU, use preferred loc.
2605  * If vm fault gpu idx is on range ACCESSIBLE bitmap, best_loc is vm fault gpu
2606  * If vm fault gpu idx is on range ACCESSIBLE_IN_PLACE bitmap, then
2607  *    if range actual loc is cpu, best_loc is cpu
2608  *    if vm fault gpu is on xgmi same hive of range actual loc gpu, best_loc is
2609  *    range actual loc.
2610  * Otherwise, GPU no access, best_loc is -1.
2611  *
2612  * Return:
2613  * -1 means vm fault GPU no access
2614  * 0 for CPU or GPU id
2615  */
2616 static int32_t
2617 svm_range_best_restore_location(struct svm_range *prange,
2618 				struct kfd_node *node,
2619 				int32_t *gpuidx)
2620 {
2621 	struct kfd_node *bo_node, *preferred_node;
2622 	struct kfd_process *p;
2623 	uint32_t gpuid;
2624 	int r;
2625 
2626 	p = container_of(prange->svms, struct kfd_process, svms);
2627 
2628 	r = kfd_process_gpuid_from_node(p, node, &gpuid, gpuidx);
2629 	if (r < 0) {
2630 		pr_debug("failed to get gpuid from kgd\n");
2631 		return -1;
2632 	}
2633 
2634 	if (node->adev->flags & AMD_IS_APU)
2635 		return 0;
2636 
2637 	if (prange->preferred_loc == gpuid ||
2638 	    prange->preferred_loc == KFD_IOCTL_SVM_LOCATION_SYSMEM) {
2639 		return prange->preferred_loc;
2640 	} else if (prange->preferred_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
2641 		preferred_node = svm_range_get_node_by_id(prange, prange->preferred_loc);
2642 		if (preferred_node && svm_nodes_in_same_hive(node, preferred_node))
2643 			return prange->preferred_loc;
2644 		/* fall through */
2645 	}
2646 
2647 	if (test_bit(*gpuidx, prange->bitmap_access))
2648 		return gpuid;
2649 
2650 	if (test_bit(*gpuidx, prange->bitmap_aip)) {
2651 		if (!prange->actual_loc)
2652 			return 0;
2653 
2654 		bo_node = svm_range_get_node_by_id(prange, prange->actual_loc);
2655 		if (bo_node && svm_nodes_in_same_hive(node, bo_node))
2656 			return prange->actual_loc;
2657 		else
2658 			return 0;
2659 	}
2660 
2661 	return -1;
2662 }
2663 
2664 static int
2665 svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
2666 			       unsigned long *start, unsigned long *last,
2667 			       bool *is_heap_stack)
2668 {
2669 	struct vm_area_struct *vma;
2670 	struct interval_tree_node *node;
2671 	struct rb_node *rb_node;
2672 	unsigned long start_limit, end_limit;
2673 
2674 	vma = vma_lookup(p->mm, addr << PAGE_SHIFT);
2675 	if (!vma) {
2676 		pr_debug("VMA does not exist in address [0x%llx]\n", addr);
2677 		return -EFAULT;
2678 	}
2679 
2680 	*is_heap_stack = vma_is_initial_heap(vma) || vma_is_initial_stack(vma);
2681 
2682 	start_limit = max(vma->vm_start >> PAGE_SHIFT,
2683 		      (unsigned long)ALIGN_DOWN(addr, 2UL << 8));
2684 	end_limit = min(vma->vm_end >> PAGE_SHIFT,
2685 		    (unsigned long)ALIGN(addr + 1, 2UL << 8));
2686 	/* First range that starts after the fault address */
2687 	node = interval_tree_iter_first(&p->svms.objects, addr + 1, ULONG_MAX);
2688 	if (node) {
2689 		end_limit = min(end_limit, node->start);
2690 		/* Last range that ends before the fault address */
2691 		rb_node = rb_prev(&node->rb);
2692 	} else {
2693 		/* Last range must end before addr because
2694 		 * there was no range after addr
2695 		 */
2696 		rb_node = rb_last(&p->svms.objects.rb_root);
2697 	}
2698 	if (rb_node) {
2699 		node = container_of(rb_node, struct interval_tree_node, rb);
2700 		if (node->last >= addr) {
2701 			WARN(1, "Overlap with prev node and page fault addr\n");
2702 			return -EFAULT;
2703 		}
2704 		start_limit = max(start_limit, node->last + 1);
2705 	}
2706 
2707 	*start = start_limit;
2708 	*last = end_limit - 1;
2709 
2710 	pr_debug("vma [0x%lx 0x%lx] range [0x%lx 0x%lx] is_heap_stack %d\n",
2711 		 vma->vm_start >> PAGE_SHIFT, vma->vm_end >> PAGE_SHIFT,
2712 		 *start, *last, *is_heap_stack);
2713 
2714 	return 0;
2715 }
2716 
2717 static int
2718 svm_range_check_vm_userptr(struct kfd_process *p, uint64_t start, uint64_t last,
2719 			   uint64_t *bo_s, uint64_t *bo_l)
2720 {
2721 	struct amdgpu_bo_va_mapping *mapping;
2722 	struct interval_tree_node *node;
2723 	struct amdgpu_bo *bo = NULL;
2724 	unsigned long userptr;
2725 	uint32_t i;
2726 	int r;
2727 
2728 	for (i = 0; i < p->n_pdds; i++) {
2729 		struct amdgpu_vm *vm;
2730 
2731 		if (!p->pdds[i]->drm_priv)
2732 			continue;
2733 
2734 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
2735 		r = amdgpu_bo_reserve(vm->root.bo, false);
2736 		if (r)
2737 			return r;
2738 
2739 		/* Check userptr by searching entire vm->va interval tree */
2740 		node = interval_tree_iter_first(&vm->va, 0, ~0ULL);
2741 		while (node) {
2742 			mapping = container_of((struct rb_node *)node,
2743 					       struct amdgpu_bo_va_mapping, rb);
2744 			bo = mapping->bo_va->base.bo;
2745 
2746 			if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm,
2747 							 start << PAGE_SHIFT,
2748 							 last << PAGE_SHIFT,
2749 							 &userptr)) {
2750 				node = interval_tree_iter_next(node, 0, ~0ULL);
2751 				continue;
2752 			}
2753 
2754 			pr_debug("[0x%llx 0x%llx] already userptr mapped\n",
2755 				 start, last);
2756 			if (bo_s && bo_l) {
2757 				*bo_s = userptr >> PAGE_SHIFT;
2758 				*bo_l = *bo_s + bo->tbo.ttm->num_pages - 1;
2759 			}
2760 			amdgpu_bo_unreserve(vm->root.bo);
2761 			return -EADDRINUSE;
2762 		}
2763 		amdgpu_bo_unreserve(vm->root.bo);
2764 	}
2765 	return 0;
2766 }
2767 
2768 static struct
2769 svm_range *svm_range_create_unregistered_range(struct kfd_node *node,
2770 						struct kfd_process *p,
2771 						struct mm_struct *mm,
2772 						int64_t addr)
2773 {
2774 	struct svm_range *prange = NULL;
2775 	unsigned long start, last;
2776 	uint32_t gpuid, gpuidx;
2777 	bool is_heap_stack;
2778 	uint64_t bo_s = 0;
2779 	uint64_t bo_l = 0;
2780 	int r;
2781 
2782 	if (svm_range_get_range_boundaries(p, addr, &start, &last,
2783 					   &is_heap_stack))
2784 		return NULL;
2785 
2786 	r = svm_range_check_vm(p, start, last, &bo_s, &bo_l);
2787 	if (r != -EADDRINUSE)
2788 		r = svm_range_check_vm_userptr(p, start, last, &bo_s, &bo_l);
2789 
2790 	if (r == -EADDRINUSE) {
2791 		if (addr >= bo_s && addr <= bo_l)
2792 			return NULL;
2793 
2794 		/* Create one page svm range if 2MB range overlapping */
2795 		start = addr;
2796 		last = addr;
2797 	}
2798 
2799 	prange = svm_range_new(&p->svms, start, last, true);
2800 	if (!prange) {
2801 		pr_debug("Failed to create prange in address [0x%llx]\n", addr);
2802 		return NULL;
2803 	}
2804 	if (kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx)) {
2805 		pr_debug("failed to get gpuid from kgd\n");
2806 		svm_range_free(prange, true);
2807 		return NULL;
2808 	}
2809 
2810 	if (is_heap_stack)
2811 		prange->preferred_loc = KFD_IOCTL_SVM_LOCATION_SYSMEM;
2812 
2813 	svm_range_add_to_svms(prange);
2814 	svm_range_add_notifier_locked(mm, prange);
2815 
2816 	return prange;
2817 }
2818 
2819 /* svm_range_skip_recover - decide if prange can be recovered
2820  * @prange: svm range structure
2821  *
2822  * GPU vm retry fault handle skip recover the range for cases:
2823  * 1. prange is on deferred list to be removed after unmap, it is stale fault,
2824  *    deferred list work will drain the stale fault before free the prange.
2825  * 2. prange is on deferred list to add interval notifier after split, or
2826  * 3. prange is child range, it is split from parent prange, recover later
2827  *    after interval notifier is added.
2828  *
2829  * Return: true to skip recover, false to recover
2830  */
2831 static bool svm_range_skip_recover(struct svm_range *prange)
2832 {
2833 	struct svm_range_list *svms = prange->svms;
2834 
2835 	spin_lock(&svms->deferred_list_lock);
2836 	if (list_empty(&prange->deferred_list) &&
2837 	    list_empty(&prange->child_list)) {
2838 		spin_unlock(&svms->deferred_list_lock);
2839 		return false;
2840 	}
2841 	spin_unlock(&svms->deferred_list_lock);
2842 
2843 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2844 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] unmapped\n",
2845 			 svms, prange, prange->start, prange->last);
2846 		return true;
2847 	}
2848 	if (prange->work_item.op == SVM_OP_ADD_RANGE_AND_MAP ||
2849 	    prange->work_item.op == SVM_OP_ADD_RANGE) {
2850 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] not added yet\n",
2851 			 svms, prange, prange->start, prange->last);
2852 		return true;
2853 	}
2854 	return false;
2855 }
2856 
2857 static void
2858 svm_range_count_fault(struct kfd_node *node, struct kfd_process *p,
2859 		      int32_t gpuidx)
2860 {
2861 	struct kfd_process_device *pdd;
2862 
2863 	/* fault is on different page of same range
2864 	 * or fault is skipped to recover later
2865 	 * or fault is on invalid virtual address
2866 	 */
2867 	if (gpuidx == MAX_GPU_INSTANCE) {
2868 		uint32_t gpuid;
2869 		int r;
2870 
2871 		r = kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx);
2872 		if (r < 0)
2873 			return;
2874 	}
2875 
2876 	/* fault is recovered
2877 	 * or fault cannot recover because GPU no access on the range
2878 	 */
2879 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
2880 	if (pdd)
2881 		WRITE_ONCE(pdd->faults, pdd->faults + 1);
2882 }
2883 
2884 static bool
2885 svm_fault_allowed(struct vm_area_struct *vma, bool write_fault)
2886 {
2887 	unsigned long requested = VM_READ;
2888 
2889 	if (write_fault)
2890 		requested |= VM_WRITE;
2891 
2892 	pr_debug("requested 0x%lx, vma permission flags 0x%lx\n", requested,
2893 		vma->vm_flags);
2894 	return (vma->vm_flags & requested) == requested;
2895 }
2896 
2897 int
2898 svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
2899 			uint32_t vmid, uint32_t node_id,
2900 			uint64_t addr, bool write_fault)
2901 {
2902 	unsigned long start, last, size;
2903 	struct mm_struct *mm = NULL;
2904 	struct svm_range_list *svms;
2905 	struct svm_range *prange;
2906 	struct kfd_process *p;
2907 	ktime_t timestamp = ktime_get_boottime();
2908 	struct kfd_node *node;
2909 	int32_t best_loc;
2910 	int32_t gpuidx = MAX_GPU_INSTANCE;
2911 	bool write_locked = false;
2912 	struct vm_area_struct *vma;
2913 	bool migration = false;
2914 	int r = 0;
2915 
2916 	if (!KFD_IS_SVM_API_SUPPORTED(adev)) {
2917 		pr_debug("device does not support SVM\n");
2918 		return -EFAULT;
2919 	}
2920 
2921 	p = kfd_lookup_process_by_pasid(pasid);
2922 	if (!p) {
2923 		pr_debug("kfd process not founded pasid 0x%x\n", pasid);
2924 		return 0;
2925 	}
2926 	svms = &p->svms;
2927 
2928 	pr_debug("restoring svms 0x%p fault address 0x%llx\n", svms, addr);
2929 
2930 	if (atomic_read(&svms->drain_pagefaults)) {
2931 		pr_debug("draining retry fault, drop fault 0x%llx\n", addr);
2932 		r = 0;
2933 		goto out;
2934 	}
2935 
2936 	if (!p->xnack_enabled) {
2937 		pr_debug("XNACK not enabled for pasid 0x%x\n", pasid);
2938 		r = -EFAULT;
2939 		goto out;
2940 	}
2941 
2942 	/* p->lead_thread is available as kfd_process_wq_release flush the work
2943 	 * before releasing task ref.
2944 	 */
2945 	mm = get_task_mm(p->lead_thread);
2946 	if (!mm) {
2947 		pr_debug("svms 0x%p failed to get mm\n", svms);
2948 		r = 0;
2949 		goto out;
2950 	}
2951 
2952 	node = kfd_node_by_irq_ids(adev, node_id, vmid);
2953 	if (!node) {
2954 		pr_debug("kfd node does not exist node_id: %d, vmid: %d\n", node_id,
2955 			 vmid);
2956 		r = -EFAULT;
2957 		goto out;
2958 	}
2959 	mmap_read_lock(mm);
2960 retry_write_locked:
2961 	mutex_lock(&svms->lock);
2962 	prange = svm_range_from_addr(svms, addr, NULL);
2963 	if (!prange) {
2964 		pr_debug("failed to find prange svms 0x%p address [0x%llx]\n",
2965 			 svms, addr);
2966 		if (!write_locked) {
2967 			/* Need the write lock to create new range with MMU notifier.
2968 			 * Also flush pending deferred work to make sure the interval
2969 			 * tree is up to date before we add a new range
2970 			 */
2971 			mutex_unlock(&svms->lock);
2972 			mmap_read_unlock(mm);
2973 			mmap_write_lock(mm);
2974 			write_locked = true;
2975 			goto retry_write_locked;
2976 		}
2977 		prange = svm_range_create_unregistered_range(node, p, mm, addr);
2978 		if (!prange) {
2979 			pr_debug("failed to create unregistered range svms 0x%p address [0x%llx]\n",
2980 				 svms, addr);
2981 			mmap_write_downgrade(mm);
2982 			r = -EFAULT;
2983 			goto out_unlock_svms;
2984 		}
2985 	}
2986 	if (write_locked)
2987 		mmap_write_downgrade(mm);
2988 
2989 	mutex_lock(&prange->migrate_mutex);
2990 
2991 	if (svm_range_skip_recover(prange)) {
2992 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
2993 		r = 0;
2994 		goto out_unlock_range;
2995 	}
2996 
2997 	/* skip duplicate vm fault on different pages of same range */
2998 	if (ktime_before(timestamp, ktime_add_ns(prange->validate_timestamp,
2999 				AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING))) {
3000 		pr_debug("svms 0x%p [0x%lx %lx] already restored\n",
3001 			 svms, prange->start, prange->last);
3002 		r = 0;
3003 		goto out_unlock_range;
3004 	}
3005 
3006 	/* __do_munmap removed VMA, return success as we are handling stale
3007 	 * retry fault.
3008 	 */
3009 	vma = vma_lookup(mm, addr << PAGE_SHIFT);
3010 	if (!vma) {
3011 		pr_debug("address 0x%llx VMA is removed\n", addr);
3012 		r = 0;
3013 		goto out_unlock_range;
3014 	}
3015 
3016 	if (!svm_fault_allowed(vma, write_fault)) {
3017 		pr_debug("fault addr 0x%llx no %s permission\n", addr,
3018 			write_fault ? "write" : "read");
3019 		r = -EPERM;
3020 		goto out_unlock_range;
3021 	}
3022 
3023 	best_loc = svm_range_best_restore_location(prange, node, &gpuidx);
3024 	if (best_loc == -1) {
3025 		pr_debug("svms %p failed get best restore loc [0x%lx 0x%lx]\n",
3026 			 svms, prange->start, prange->last);
3027 		r = -EACCES;
3028 		goto out_unlock_range;
3029 	}
3030 
3031 	pr_debug("svms %p [0x%lx 0x%lx] best restore 0x%x, actual loc 0x%x\n",
3032 		 svms, prange->start, prange->last, best_loc,
3033 		 prange->actual_loc);
3034 
3035 	kfd_smi_event_page_fault_start(node, p->lead_thread->pid, addr,
3036 				       write_fault, timestamp);
3037 
3038 	/* Align migration range start and size to granularity size */
3039 	size = 1UL << prange->granularity;
3040 	start = max_t(unsigned long, ALIGN_DOWN(addr, size), prange->start);
3041 	last = min_t(unsigned long, ALIGN(addr + 1, size) - 1, prange->last);
3042 	if (prange->actual_loc != 0 || best_loc != 0) {
3043 		migration = true;
3044 
3045 		if (best_loc) {
3046 			r = svm_migrate_to_vram(prange, best_loc, start, last,
3047 					mm, KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU);
3048 			if (r) {
3049 				pr_debug("svm_migrate_to_vram failed (%d) at %llx, falling back to system memory\n",
3050 					 r, addr);
3051 				/* Fallback to system memory if migration to
3052 				 * VRAM failed
3053 				 */
3054 				if (prange->actual_loc && prange->actual_loc != best_loc)
3055 					r = svm_migrate_vram_to_ram(prange, mm, start, last,
3056 						KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU, NULL);
3057 				else
3058 					r = 0;
3059 			}
3060 		} else {
3061 			r = svm_migrate_vram_to_ram(prange, mm, start, last,
3062 					KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU, NULL);
3063 		}
3064 		if (r) {
3065 			pr_debug("failed %d to migrate svms %p [0x%lx 0x%lx]\n",
3066 				 r, svms, start, last);
3067 			goto out_unlock_range;
3068 		}
3069 	}
3070 
3071 	r = svm_range_validate_and_map(mm, start, last, prange, gpuidx, false,
3072 				       false, false);
3073 	if (r)
3074 		pr_debug("failed %d to map svms 0x%p [0x%lx 0x%lx] to gpus\n",
3075 			 r, svms, start, last);
3076 
3077 	kfd_smi_event_page_fault_end(node, p->lead_thread->pid, addr,
3078 				     migration);
3079 
3080 out_unlock_range:
3081 	mutex_unlock(&prange->migrate_mutex);
3082 out_unlock_svms:
3083 	mutex_unlock(&svms->lock);
3084 	mmap_read_unlock(mm);
3085 
3086 	svm_range_count_fault(node, p, gpuidx);
3087 
3088 	mmput(mm);
3089 out:
3090 	kfd_unref_process(p);
3091 
3092 	if (r == -EAGAIN) {
3093 		pr_debug("recover vm fault later\n");
3094 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
3095 		r = 0;
3096 	}
3097 	return r;
3098 }
3099 
3100 int
3101 svm_range_switch_xnack_reserve_mem(struct kfd_process *p, bool xnack_enabled)
3102 {
3103 	struct svm_range *prange, *pchild;
3104 	uint64_t reserved_size = 0;
3105 	uint64_t size;
3106 	int r = 0;
3107 
3108 	pr_debug("switching xnack from %d to %d\n", p->xnack_enabled, xnack_enabled);
3109 
3110 	mutex_lock(&p->svms.lock);
3111 
3112 	list_for_each_entry(prange, &p->svms.list, list) {
3113 		svm_range_lock(prange);
3114 		list_for_each_entry(pchild, &prange->child_list, child_list) {
3115 			size = (pchild->last - pchild->start + 1) << PAGE_SHIFT;
3116 			if (xnack_enabled) {
3117 				amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3118 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3119 			} else {
3120 				r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3121 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3122 				if (r)
3123 					goto out_unlock;
3124 				reserved_size += size;
3125 			}
3126 		}
3127 
3128 		size = (prange->last - prange->start + 1) << PAGE_SHIFT;
3129 		if (xnack_enabled) {
3130 			amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3131 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3132 		} else {
3133 			r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3134 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3135 			if (r)
3136 				goto out_unlock;
3137 			reserved_size += size;
3138 		}
3139 out_unlock:
3140 		svm_range_unlock(prange);
3141 		if (r)
3142 			break;
3143 	}
3144 
3145 	if (r)
3146 		amdgpu_amdkfd_unreserve_mem_limit(NULL, reserved_size,
3147 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3148 	else
3149 		/* Change xnack mode must be inside svms lock, to avoid race with
3150 		 * svm_range_deferred_list_work unreserve memory in parallel.
3151 		 */
3152 		p->xnack_enabled = xnack_enabled;
3153 
3154 	mutex_unlock(&p->svms.lock);
3155 	return r;
3156 }
3157 
3158 void svm_range_list_fini(struct kfd_process *p)
3159 {
3160 	struct svm_range *prange;
3161 	struct svm_range *next;
3162 
3163 	pr_debug("pasid 0x%x svms 0x%p\n", p->pasid, &p->svms);
3164 
3165 	cancel_delayed_work_sync(&p->svms.restore_work);
3166 
3167 	/* Ensure list work is finished before process is destroyed */
3168 	flush_work(&p->svms.deferred_list_work);
3169 
3170 	/*
3171 	 * Ensure no retry fault comes in afterwards, as page fault handler will
3172 	 * not find kfd process and take mm lock to recover fault.
3173 	 */
3174 	atomic_inc(&p->svms.drain_pagefaults);
3175 	svm_range_drain_retry_fault(&p->svms);
3176 
3177 	list_for_each_entry_safe(prange, next, &p->svms.list, list) {
3178 		svm_range_unlink(prange);
3179 		svm_range_remove_notifier(prange);
3180 		svm_range_free(prange, true);
3181 	}
3182 
3183 	mutex_destroy(&p->svms.lock);
3184 
3185 	pr_debug("pasid 0x%x svms 0x%p done\n", p->pasid, &p->svms);
3186 }
3187 
3188 int svm_range_list_init(struct kfd_process *p)
3189 {
3190 	struct svm_range_list *svms = &p->svms;
3191 	int i;
3192 
3193 	svms->objects = RB_ROOT_CACHED;
3194 	mutex_init(&svms->lock);
3195 	INIT_LIST_HEAD(&svms->list);
3196 	atomic_set(&svms->evicted_ranges, 0);
3197 	atomic_set(&svms->drain_pagefaults, 0);
3198 	INIT_DELAYED_WORK(&svms->restore_work, svm_range_restore_work);
3199 	INIT_WORK(&svms->deferred_list_work, svm_range_deferred_list_work);
3200 	INIT_LIST_HEAD(&svms->deferred_range_list);
3201 	INIT_LIST_HEAD(&svms->criu_svm_metadata_list);
3202 	spin_lock_init(&svms->deferred_list_lock);
3203 
3204 	for (i = 0; i < p->n_pdds; i++)
3205 		if (KFD_IS_SVM_API_SUPPORTED(p->pdds[i]->dev->adev))
3206 			bitmap_set(svms->bitmap_supported, i, 1);
3207 
3208 	return 0;
3209 }
3210 
3211 /**
3212  * svm_range_check_vm - check if virtual address range mapped already
3213  * @p: current kfd_process
3214  * @start: range start address, in pages
3215  * @last: range last address, in pages
3216  * @bo_s: mapping start address in pages if address range already mapped
3217  * @bo_l: mapping last address in pages if address range already mapped
3218  *
3219  * The purpose is to avoid virtual address ranges already allocated by
3220  * kfd_ioctl_alloc_memory_of_gpu ioctl.
3221  * It looks for each pdd in the kfd_process.
3222  *
3223  * Context: Process context
3224  *
3225  * Return 0 - OK, if the range is not mapped.
3226  * Otherwise error code:
3227  * -EADDRINUSE - if address is mapped already by kfd_ioctl_alloc_memory_of_gpu
3228  * -ERESTARTSYS - A wait for the buffer to become unreserved was interrupted by
3229  * a signal. Release all buffer reservations and return to user-space.
3230  */
3231 static int
3232 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
3233 		   uint64_t *bo_s, uint64_t *bo_l)
3234 {
3235 	struct amdgpu_bo_va_mapping *mapping;
3236 	struct interval_tree_node *node;
3237 	uint32_t i;
3238 	int r;
3239 
3240 	for (i = 0; i < p->n_pdds; i++) {
3241 		struct amdgpu_vm *vm;
3242 
3243 		if (!p->pdds[i]->drm_priv)
3244 			continue;
3245 
3246 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
3247 		r = amdgpu_bo_reserve(vm->root.bo, false);
3248 		if (r)
3249 			return r;
3250 
3251 		node = interval_tree_iter_first(&vm->va, start, last);
3252 		if (node) {
3253 			pr_debug("range [0x%llx 0x%llx] already TTM mapped\n",
3254 				 start, last);
3255 			mapping = container_of((struct rb_node *)node,
3256 					       struct amdgpu_bo_va_mapping, rb);
3257 			if (bo_s && bo_l) {
3258 				*bo_s = mapping->start;
3259 				*bo_l = mapping->last;
3260 			}
3261 			amdgpu_bo_unreserve(vm->root.bo);
3262 			return -EADDRINUSE;
3263 		}
3264 		amdgpu_bo_unreserve(vm->root.bo);
3265 	}
3266 
3267 	return 0;
3268 }
3269 
3270 /**
3271  * svm_range_is_valid - check if virtual address range is valid
3272  * @p: current kfd_process
3273  * @start: range start address, in pages
3274  * @size: range size, in pages
3275  *
3276  * Valid virtual address range means it belongs to one or more VMAs
3277  *
3278  * Context: Process context
3279  *
3280  * Return:
3281  *  0 - OK, otherwise error code
3282  */
3283 static int
3284 svm_range_is_valid(struct kfd_process *p, uint64_t start, uint64_t size)
3285 {
3286 	const unsigned long device_vma = VM_IO | VM_PFNMAP | VM_MIXEDMAP;
3287 	struct vm_area_struct *vma;
3288 	unsigned long end;
3289 	unsigned long start_unchg = start;
3290 
3291 	start <<= PAGE_SHIFT;
3292 	end = start + (size << PAGE_SHIFT);
3293 	do {
3294 		vma = vma_lookup(p->mm, start);
3295 		if (!vma || (vma->vm_flags & device_vma))
3296 			return -EFAULT;
3297 		start = min(end, vma->vm_end);
3298 	} while (start < end);
3299 
3300 	return svm_range_check_vm(p, start_unchg, (end - 1) >> PAGE_SHIFT, NULL,
3301 				  NULL);
3302 }
3303 
3304 /**
3305  * svm_range_best_prefetch_location - decide the best prefetch location
3306  * @prange: svm range structure
3307  *
3308  * For xnack off:
3309  * If range map to single GPU, the best prefetch location is prefetch_loc, which
3310  * can be CPU or GPU.
3311  *
3312  * If range is ACCESS or ACCESS_IN_PLACE by mGPUs, only if mGPU connection on
3313  * XGMI same hive, the best prefetch location is prefetch_loc GPU, othervise
3314  * the best prefetch location is always CPU, because GPU can not have coherent
3315  * mapping VRAM of other GPUs even with large-BAR PCIe connection.
3316  *
3317  * For xnack on:
3318  * If range is not ACCESS_IN_PLACE by mGPUs, the best prefetch location is
3319  * prefetch_loc, other GPU access will generate vm fault and trigger migration.
3320  *
3321  * If range is ACCESS_IN_PLACE by mGPUs, only if mGPU connection on XGMI same
3322  * hive, the best prefetch location is prefetch_loc GPU, otherwise the best
3323  * prefetch location is always CPU.
3324  *
3325  * Context: Process context
3326  *
3327  * Return:
3328  * 0 for CPU or GPU id
3329  */
3330 static uint32_t
3331 svm_range_best_prefetch_location(struct svm_range *prange)
3332 {
3333 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
3334 	uint32_t best_loc = prange->prefetch_loc;
3335 	struct kfd_process_device *pdd;
3336 	struct kfd_node *bo_node;
3337 	struct kfd_process *p;
3338 	uint32_t gpuidx;
3339 
3340 	p = container_of(prange->svms, struct kfd_process, svms);
3341 
3342 	if (!best_loc || best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED)
3343 		goto out;
3344 
3345 	bo_node = svm_range_get_node_by_id(prange, best_loc);
3346 	if (!bo_node) {
3347 		WARN_ONCE(1, "failed to get valid kfd node at id%x\n", best_loc);
3348 		best_loc = 0;
3349 		goto out;
3350 	}
3351 
3352 	if (bo_node->adev->flags & AMD_IS_APU) {
3353 		best_loc = 0;
3354 		goto out;
3355 	}
3356 
3357 	if (p->xnack_enabled)
3358 		bitmap_copy(bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
3359 	else
3360 		bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
3361 			  MAX_GPU_INSTANCE);
3362 
3363 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
3364 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
3365 		if (!pdd) {
3366 			pr_debug("failed to get device by idx 0x%x\n", gpuidx);
3367 			continue;
3368 		}
3369 
3370 		if (pdd->dev->adev == bo_node->adev)
3371 			continue;
3372 
3373 		if (!svm_nodes_in_same_hive(pdd->dev, bo_node)) {
3374 			best_loc = 0;
3375 			break;
3376 		}
3377 	}
3378 
3379 out:
3380 	pr_debug("xnack %d svms 0x%p [0x%lx 0x%lx] best loc 0x%x\n",
3381 		 p->xnack_enabled, &p->svms, prange->start, prange->last,
3382 		 best_loc);
3383 
3384 	return best_loc;
3385 }
3386 
3387 /* svm_range_trigger_migration - start page migration if prefetch loc changed
3388  * @mm: current process mm_struct
3389  * @prange: svm range structure
3390  * @migrated: output, true if migration is triggered
3391  *
3392  * If range perfetch_loc is GPU, actual loc is cpu 0, then migrate the range
3393  * from ram to vram.
3394  * If range prefetch_loc is cpu 0, actual loc is GPU, then migrate the range
3395  * from vram to ram.
3396  *
3397  * If GPU vm fault retry is not enabled, migration interact with MMU notifier
3398  * and restore work:
3399  * 1. migrate_vma_setup invalidate pages, MMU notifier callback svm_range_evict
3400  *    stops all queues, schedule restore work
3401  * 2. svm_range_restore_work wait for migration is done by
3402  *    a. svm_range_validate_vram takes prange->migrate_mutex
3403  *    b. svm_range_validate_ram HMM get pages wait for CPU fault handle returns
3404  * 3. restore work update mappings of GPU, resume all queues.
3405  *
3406  * Context: Process context
3407  *
3408  * Return:
3409  * 0 - OK, otherwise - error code of migration
3410  */
3411 static int
3412 svm_range_trigger_migration(struct mm_struct *mm, struct svm_range *prange,
3413 			    bool *migrated)
3414 {
3415 	uint32_t best_loc;
3416 	int r = 0;
3417 
3418 	*migrated = false;
3419 	best_loc = svm_range_best_prefetch_location(prange);
3420 
3421 	/* when best_loc is a gpu node and same as prange->actual_loc
3422 	 * we still need do migration as prange->actual_loc !=0 does
3423 	 * not mean all pages in prange are vram. hmm migrate will pick
3424 	 * up right pages during migration.
3425 	 */
3426 	if ((best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED) ||
3427 	    (best_loc == 0 && prange->actual_loc == 0))
3428 		return 0;
3429 
3430 	if (!best_loc) {
3431 		r = svm_migrate_vram_to_ram(prange, mm, prange->start, prange->last,
3432 					KFD_MIGRATE_TRIGGER_PREFETCH, NULL);
3433 		*migrated = !r;
3434 		return r;
3435 	}
3436 
3437 	r = svm_migrate_to_vram(prange, best_loc, prange->start, prange->last,
3438 				mm, KFD_MIGRATE_TRIGGER_PREFETCH);
3439 	*migrated = !r;
3440 
3441 	return 0;
3442 }
3443 
3444 int svm_range_schedule_evict_svm_bo(struct amdgpu_amdkfd_fence *fence)
3445 {
3446 	/* Dereferencing fence->svm_bo is safe here because the fence hasn't
3447 	 * signaled yet and we're under the protection of the fence->lock.
3448 	 * After the fence is signaled in svm_range_bo_release, we cannot get
3449 	 * here any more.
3450 	 *
3451 	 * Reference is dropped in svm_range_evict_svm_bo_worker.
3452 	 */
3453 	if (svm_bo_ref_unless_zero(fence->svm_bo)) {
3454 		WRITE_ONCE(fence->svm_bo->evicting, 1);
3455 		schedule_work(&fence->svm_bo->eviction_work);
3456 	}
3457 
3458 	return 0;
3459 }
3460 
3461 static void svm_range_evict_svm_bo_worker(struct work_struct *work)
3462 {
3463 	struct svm_range_bo *svm_bo;
3464 	struct mm_struct *mm;
3465 	int r = 0;
3466 
3467 	svm_bo = container_of(work, struct svm_range_bo, eviction_work);
3468 
3469 	if (mmget_not_zero(svm_bo->eviction_fence->mm)) {
3470 		mm = svm_bo->eviction_fence->mm;
3471 	} else {
3472 		svm_range_bo_unref(svm_bo);
3473 		return;
3474 	}
3475 
3476 	mmap_read_lock(mm);
3477 	spin_lock(&svm_bo->list_lock);
3478 	while (!list_empty(&svm_bo->range_list) && !r) {
3479 		struct svm_range *prange =
3480 				list_first_entry(&svm_bo->range_list,
3481 						struct svm_range, svm_bo_list);
3482 		int retries = 3;
3483 
3484 		list_del_init(&prange->svm_bo_list);
3485 		spin_unlock(&svm_bo->list_lock);
3486 
3487 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
3488 			 prange->start, prange->last);
3489 
3490 		mutex_lock(&prange->migrate_mutex);
3491 		do {
3492 			/* migrate all vram pages in this prange to sys ram
3493 			 * after that prange->actual_loc should be zero
3494 			 */
3495 			r = svm_migrate_vram_to_ram(prange, mm,
3496 					prange->start, prange->last,
3497 					KFD_MIGRATE_TRIGGER_TTM_EVICTION, NULL);
3498 		} while (!r && prange->actual_loc && --retries);
3499 
3500 		if (!r && prange->actual_loc)
3501 			pr_info_once("Migration failed during eviction");
3502 
3503 		if (!prange->actual_loc) {
3504 			mutex_lock(&prange->lock);
3505 			prange->svm_bo = NULL;
3506 			mutex_unlock(&prange->lock);
3507 		}
3508 		mutex_unlock(&prange->migrate_mutex);
3509 
3510 		spin_lock(&svm_bo->list_lock);
3511 	}
3512 	spin_unlock(&svm_bo->list_lock);
3513 	mmap_read_unlock(mm);
3514 	mmput(mm);
3515 
3516 	dma_fence_signal(&svm_bo->eviction_fence->base);
3517 
3518 	/* This is the last reference to svm_bo, after svm_range_vram_node_free
3519 	 * has been called in svm_migrate_vram_to_ram
3520 	 */
3521 	WARN_ONCE(!r && kref_read(&svm_bo->kref) != 1, "This was not the last reference\n");
3522 	svm_range_bo_unref(svm_bo);
3523 }
3524 
3525 static int
3526 svm_range_set_attr(struct kfd_process *p, struct mm_struct *mm,
3527 		   uint64_t start, uint64_t size, uint32_t nattr,
3528 		   struct kfd_ioctl_svm_attribute *attrs)
3529 {
3530 	struct amdkfd_process_info *process_info = p->kgd_process_info;
3531 	struct list_head update_list;
3532 	struct list_head insert_list;
3533 	struct list_head remove_list;
3534 	struct list_head remap_list;
3535 	struct svm_range_list *svms;
3536 	struct svm_range *prange;
3537 	struct svm_range *next;
3538 	bool update_mapping = false;
3539 	bool flush_tlb;
3540 	int r, ret = 0;
3541 
3542 	pr_debug("pasid 0x%x svms 0x%p [0x%llx 0x%llx] pages 0x%llx\n",
3543 		 p->pasid, &p->svms, start, start + size - 1, size);
3544 
3545 	r = svm_range_check_attr(p, nattr, attrs);
3546 	if (r)
3547 		return r;
3548 
3549 	svms = &p->svms;
3550 
3551 	mutex_lock(&process_info->lock);
3552 
3553 	svm_range_list_lock_and_flush_work(svms, mm);
3554 
3555 	r = svm_range_is_valid(p, start, size);
3556 	if (r) {
3557 		pr_debug("invalid range r=%d\n", r);
3558 		mmap_write_unlock(mm);
3559 		goto out;
3560 	}
3561 
3562 	mutex_lock(&svms->lock);
3563 
3564 	/* Add new range and split existing ranges as needed */
3565 	r = svm_range_add(p, start, size, nattr, attrs, &update_list,
3566 			  &insert_list, &remove_list, &remap_list);
3567 	if (r) {
3568 		mutex_unlock(&svms->lock);
3569 		mmap_write_unlock(mm);
3570 		goto out;
3571 	}
3572 	/* Apply changes as a transaction */
3573 	list_for_each_entry_safe(prange, next, &insert_list, list) {
3574 		svm_range_add_to_svms(prange);
3575 		svm_range_add_notifier_locked(mm, prange);
3576 	}
3577 	list_for_each_entry(prange, &update_list, update_list) {
3578 		svm_range_apply_attrs(p, prange, nattr, attrs, &update_mapping);
3579 		/* TODO: unmap ranges from GPU that lost access */
3580 	}
3581 	list_for_each_entry_safe(prange, next, &remove_list, update_list) {
3582 		pr_debug("unlink old 0x%p prange 0x%p [0x%lx 0x%lx]\n",
3583 			 prange->svms, prange, prange->start,
3584 			 prange->last);
3585 		svm_range_unlink(prange);
3586 		svm_range_remove_notifier(prange);
3587 		svm_range_free(prange, false);
3588 	}
3589 
3590 	mmap_write_downgrade(mm);
3591 	/* Trigger migrations and revalidate and map to GPUs as needed. If
3592 	 * this fails we may be left with partially completed actions. There
3593 	 * is no clean way of rolling back to the previous state in such a
3594 	 * case because the rollback wouldn't be guaranteed to work either.
3595 	 */
3596 	list_for_each_entry(prange, &update_list, update_list) {
3597 		bool migrated;
3598 
3599 		mutex_lock(&prange->migrate_mutex);
3600 
3601 		r = svm_range_trigger_migration(mm, prange, &migrated);
3602 		if (r)
3603 			goto out_unlock_range;
3604 
3605 		if (migrated && (!p->xnack_enabled ||
3606 		    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) &&
3607 		    prange->mapped_to_gpu) {
3608 			pr_debug("restore_work will update mappings of GPUs\n");
3609 			mutex_unlock(&prange->migrate_mutex);
3610 			continue;
3611 		}
3612 
3613 		if (!migrated && !update_mapping) {
3614 			mutex_unlock(&prange->migrate_mutex);
3615 			continue;
3616 		}
3617 
3618 		flush_tlb = !migrated && update_mapping && prange->mapped_to_gpu;
3619 
3620 		r = svm_range_validate_and_map(mm, prange->start, prange->last, prange,
3621 					       MAX_GPU_INSTANCE, true, true, flush_tlb);
3622 		if (r)
3623 			pr_debug("failed %d to map svm range\n", r);
3624 
3625 out_unlock_range:
3626 		mutex_unlock(&prange->migrate_mutex);
3627 		if (r)
3628 			ret = r;
3629 	}
3630 
3631 	list_for_each_entry(prange, &remap_list, update_list) {
3632 		pr_debug("Remapping prange 0x%p [0x%lx 0x%lx]\n",
3633 			 prange, prange->start, prange->last);
3634 		mutex_lock(&prange->migrate_mutex);
3635 		r = svm_range_validate_and_map(mm,  prange->start, prange->last, prange,
3636 					       MAX_GPU_INSTANCE, true, true, prange->mapped_to_gpu);
3637 		if (r)
3638 			pr_debug("failed %d on remap svm range\n", r);
3639 		mutex_unlock(&prange->migrate_mutex);
3640 		if (r)
3641 			ret = r;
3642 	}
3643 
3644 	dynamic_svm_range_dump(svms);
3645 
3646 	mutex_unlock(&svms->lock);
3647 	mmap_read_unlock(mm);
3648 out:
3649 	mutex_unlock(&process_info->lock);
3650 
3651 	pr_debug("pasid 0x%x svms 0x%p [0x%llx 0x%llx] done, r=%d\n", p->pasid,
3652 		 &p->svms, start, start + size - 1, r);
3653 
3654 	return ret ? ret : r;
3655 }
3656 
3657 static int
3658 svm_range_get_attr(struct kfd_process *p, struct mm_struct *mm,
3659 		   uint64_t start, uint64_t size, uint32_t nattr,
3660 		   struct kfd_ioctl_svm_attribute *attrs)
3661 {
3662 	DECLARE_BITMAP(bitmap_access, MAX_GPU_INSTANCE);
3663 	DECLARE_BITMAP(bitmap_aip, MAX_GPU_INSTANCE);
3664 	bool get_preferred_loc = false;
3665 	bool get_prefetch_loc = false;
3666 	bool get_granularity = false;
3667 	bool get_accessible = false;
3668 	bool get_flags = false;
3669 	uint64_t last = start + size - 1UL;
3670 	uint8_t granularity = 0xff;
3671 	struct interval_tree_node *node;
3672 	struct svm_range_list *svms;
3673 	struct svm_range *prange;
3674 	uint32_t prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3675 	uint32_t location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3676 	uint32_t flags_and = 0xffffffff;
3677 	uint32_t flags_or = 0;
3678 	int gpuidx;
3679 	uint32_t i;
3680 	int r = 0;
3681 
3682 	pr_debug("svms 0x%p [0x%llx 0x%llx] nattr 0x%x\n", &p->svms, start,
3683 		 start + size - 1, nattr);
3684 
3685 	/* Flush pending deferred work to avoid racing with deferred actions from
3686 	 * previous memory map changes (e.g. munmap). Concurrent memory map changes
3687 	 * can still race with get_attr because we don't hold the mmap lock. But that
3688 	 * would be a race condition in the application anyway, and undefined
3689 	 * behaviour is acceptable in that case.
3690 	 */
3691 	flush_work(&p->svms.deferred_list_work);
3692 
3693 	mmap_read_lock(mm);
3694 	r = svm_range_is_valid(p, start, size);
3695 	mmap_read_unlock(mm);
3696 	if (r) {
3697 		pr_debug("invalid range r=%d\n", r);
3698 		return r;
3699 	}
3700 
3701 	for (i = 0; i < nattr; i++) {
3702 		switch (attrs[i].type) {
3703 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3704 			get_preferred_loc = true;
3705 			break;
3706 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3707 			get_prefetch_loc = true;
3708 			break;
3709 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3710 			get_accessible = true;
3711 			break;
3712 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3713 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3714 			get_flags = true;
3715 			break;
3716 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3717 			get_granularity = true;
3718 			break;
3719 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
3720 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
3721 			fallthrough;
3722 		default:
3723 			pr_debug("get invalid attr type 0x%x\n", attrs[i].type);
3724 			return -EINVAL;
3725 		}
3726 	}
3727 
3728 	svms = &p->svms;
3729 
3730 	mutex_lock(&svms->lock);
3731 
3732 	node = interval_tree_iter_first(&svms->objects, start, last);
3733 	if (!node) {
3734 		pr_debug("range attrs not found return default values\n");
3735 		svm_range_set_default_attributes(&location, &prefetch_loc,
3736 						 &granularity, &flags_and);
3737 		flags_or = flags_and;
3738 		if (p->xnack_enabled)
3739 			bitmap_copy(bitmap_access, svms->bitmap_supported,
3740 				    MAX_GPU_INSTANCE);
3741 		else
3742 			bitmap_zero(bitmap_access, MAX_GPU_INSTANCE);
3743 		bitmap_zero(bitmap_aip, MAX_GPU_INSTANCE);
3744 		goto fill_values;
3745 	}
3746 	bitmap_copy(bitmap_access, svms->bitmap_supported, MAX_GPU_INSTANCE);
3747 	bitmap_copy(bitmap_aip, svms->bitmap_supported, MAX_GPU_INSTANCE);
3748 
3749 	while (node) {
3750 		struct interval_tree_node *next;
3751 
3752 		prange = container_of(node, struct svm_range, it_node);
3753 		next = interval_tree_iter_next(node, start, last);
3754 
3755 		if (get_preferred_loc) {
3756 			if (prange->preferred_loc ==
3757 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3758 			    (location != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3759 			     location != prange->preferred_loc)) {
3760 				location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3761 				get_preferred_loc = false;
3762 			} else {
3763 				location = prange->preferred_loc;
3764 			}
3765 		}
3766 		if (get_prefetch_loc) {
3767 			if (prange->prefetch_loc ==
3768 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3769 			    (prefetch_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3770 			     prefetch_loc != prange->prefetch_loc)) {
3771 				prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3772 				get_prefetch_loc = false;
3773 			} else {
3774 				prefetch_loc = prange->prefetch_loc;
3775 			}
3776 		}
3777 		if (get_accessible) {
3778 			bitmap_and(bitmap_access, bitmap_access,
3779 				   prange->bitmap_access, MAX_GPU_INSTANCE);
3780 			bitmap_and(bitmap_aip, bitmap_aip,
3781 				   prange->bitmap_aip, MAX_GPU_INSTANCE);
3782 		}
3783 		if (get_flags) {
3784 			flags_and &= prange->flags;
3785 			flags_or |= prange->flags;
3786 		}
3787 
3788 		if (get_granularity && prange->granularity < granularity)
3789 			granularity = prange->granularity;
3790 
3791 		node = next;
3792 	}
3793 fill_values:
3794 	mutex_unlock(&svms->lock);
3795 
3796 	for (i = 0; i < nattr; i++) {
3797 		switch (attrs[i].type) {
3798 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3799 			attrs[i].value = location;
3800 			break;
3801 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3802 			attrs[i].value = prefetch_loc;
3803 			break;
3804 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3805 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
3806 							       attrs[i].value);
3807 			if (gpuidx < 0) {
3808 				pr_debug("invalid gpuid %x\n", attrs[i].value);
3809 				return -EINVAL;
3810 			}
3811 			if (test_bit(gpuidx, bitmap_access))
3812 				attrs[i].type = KFD_IOCTL_SVM_ATTR_ACCESS;
3813 			else if (test_bit(gpuidx, bitmap_aip))
3814 				attrs[i].type =
3815 					KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE;
3816 			else
3817 				attrs[i].type = KFD_IOCTL_SVM_ATTR_NO_ACCESS;
3818 			break;
3819 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3820 			attrs[i].value = flags_and;
3821 			break;
3822 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3823 			attrs[i].value = ~flags_or;
3824 			break;
3825 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3826 			attrs[i].value = (uint32_t)granularity;
3827 			break;
3828 		}
3829 	}
3830 
3831 	return 0;
3832 }
3833 
3834 int kfd_criu_resume_svm(struct kfd_process *p)
3835 {
3836 	struct kfd_ioctl_svm_attribute *set_attr_new, *set_attr = NULL;
3837 	int nattr_common = 4, nattr_accessibility = 1;
3838 	struct criu_svm_metadata *criu_svm_md = NULL;
3839 	struct svm_range_list *svms = &p->svms;
3840 	struct criu_svm_metadata *next = NULL;
3841 	uint32_t set_flags = 0xffffffff;
3842 	int i, j, num_attrs, ret = 0;
3843 	uint64_t set_attr_size;
3844 	struct mm_struct *mm;
3845 
3846 	if (list_empty(&svms->criu_svm_metadata_list)) {
3847 		pr_debug("No SVM data from CRIU restore stage 2\n");
3848 		return ret;
3849 	}
3850 
3851 	mm = get_task_mm(p->lead_thread);
3852 	if (!mm) {
3853 		pr_err("failed to get mm for the target process\n");
3854 		return -ESRCH;
3855 	}
3856 
3857 	num_attrs = nattr_common + (nattr_accessibility * p->n_pdds);
3858 
3859 	i = j = 0;
3860 	list_for_each_entry(criu_svm_md, &svms->criu_svm_metadata_list, list) {
3861 		pr_debug("criu_svm_md[%d]\n\tstart: 0x%llx size: 0x%llx (npages)\n",
3862 			 i, criu_svm_md->data.start_addr, criu_svm_md->data.size);
3863 
3864 		for (j = 0; j < num_attrs; j++) {
3865 			pr_debug("\ncriu_svm_md[%d]->attrs[%d].type : 0x%x\ncriu_svm_md[%d]->attrs[%d].value : 0x%x\n",
3866 				 i, j, criu_svm_md->data.attrs[j].type,
3867 				 i, j, criu_svm_md->data.attrs[j].value);
3868 			switch (criu_svm_md->data.attrs[j].type) {
3869 			/* During Checkpoint operation, the query for
3870 			 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC attribute might
3871 			 * return KFD_IOCTL_SVM_LOCATION_UNDEFINED if they were
3872 			 * not used by the range which was checkpointed. Care
3873 			 * must be taken to not restore with an invalid value
3874 			 * otherwise the gpuidx value will be invalid and
3875 			 * set_attr would eventually fail so just replace those
3876 			 * with another dummy attribute such as
3877 			 * KFD_IOCTL_SVM_ATTR_SET_FLAGS.
3878 			 */
3879 			case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3880 				if (criu_svm_md->data.attrs[j].value ==
3881 				    KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
3882 					criu_svm_md->data.attrs[j].type =
3883 						KFD_IOCTL_SVM_ATTR_SET_FLAGS;
3884 					criu_svm_md->data.attrs[j].value = 0;
3885 				}
3886 				break;
3887 			case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3888 				set_flags = criu_svm_md->data.attrs[j].value;
3889 				break;
3890 			default:
3891 				break;
3892 			}
3893 		}
3894 
3895 		/* CLR_FLAGS is not available via get_attr during checkpoint but
3896 		 * it needs to be inserted before restoring the ranges so
3897 		 * allocate extra space for it before calling set_attr
3898 		 */
3899 		set_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
3900 						(num_attrs + 1);
3901 		set_attr_new = krealloc(set_attr, set_attr_size,
3902 					    GFP_KERNEL);
3903 		if (!set_attr_new) {
3904 			ret = -ENOMEM;
3905 			goto exit;
3906 		}
3907 		set_attr = set_attr_new;
3908 
3909 		memcpy(set_attr, criu_svm_md->data.attrs, num_attrs *
3910 					sizeof(struct kfd_ioctl_svm_attribute));
3911 		set_attr[num_attrs].type = KFD_IOCTL_SVM_ATTR_CLR_FLAGS;
3912 		set_attr[num_attrs].value = ~set_flags;
3913 
3914 		ret = svm_range_set_attr(p, mm, criu_svm_md->data.start_addr,
3915 					 criu_svm_md->data.size, num_attrs + 1,
3916 					 set_attr);
3917 		if (ret) {
3918 			pr_err("CRIU: failed to set range attributes\n");
3919 			goto exit;
3920 		}
3921 
3922 		i++;
3923 	}
3924 exit:
3925 	kfree(set_attr);
3926 	list_for_each_entry_safe(criu_svm_md, next, &svms->criu_svm_metadata_list, list) {
3927 		pr_debug("freeing criu_svm_md[]\n\tstart: 0x%llx\n",
3928 						criu_svm_md->data.start_addr);
3929 		kfree(criu_svm_md);
3930 	}
3931 
3932 	mmput(mm);
3933 	return ret;
3934 
3935 }
3936 
3937 int kfd_criu_restore_svm(struct kfd_process *p,
3938 			 uint8_t __user *user_priv_ptr,
3939 			 uint64_t *priv_data_offset,
3940 			 uint64_t max_priv_data_size)
3941 {
3942 	uint64_t svm_priv_data_size, svm_object_md_size, svm_attrs_size;
3943 	int nattr_common = 4, nattr_accessibility = 1;
3944 	struct criu_svm_metadata *criu_svm_md = NULL;
3945 	struct svm_range_list *svms = &p->svms;
3946 	uint32_t num_devices;
3947 	int ret = 0;
3948 
3949 	num_devices = p->n_pdds;
3950 	/* Handle one SVM range object at a time, also the number of gpus are
3951 	 * assumed to be same on the restore node, checking must be done while
3952 	 * evaluating the topology earlier
3953 	 */
3954 
3955 	svm_attrs_size = sizeof(struct kfd_ioctl_svm_attribute) *
3956 		(nattr_common + nattr_accessibility * num_devices);
3957 	svm_object_md_size = sizeof(struct criu_svm_metadata) + svm_attrs_size;
3958 
3959 	svm_priv_data_size = sizeof(struct kfd_criu_svm_range_priv_data) +
3960 								svm_attrs_size;
3961 
3962 	criu_svm_md = kzalloc(svm_object_md_size, GFP_KERNEL);
3963 	if (!criu_svm_md) {
3964 		pr_err("failed to allocate memory to store svm metadata\n");
3965 		return -ENOMEM;
3966 	}
3967 	if (*priv_data_offset + svm_priv_data_size > max_priv_data_size) {
3968 		ret = -EINVAL;
3969 		goto exit;
3970 	}
3971 
3972 	ret = copy_from_user(&criu_svm_md->data, user_priv_ptr + *priv_data_offset,
3973 			     svm_priv_data_size);
3974 	if (ret) {
3975 		ret = -EFAULT;
3976 		goto exit;
3977 	}
3978 	*priv_data_offset += svm_priv_data_size;
3979 
3980 	list_add_tail(&criu_svm_md->list, &svms->criu_svm_metadata_list);
3981 
3982 	return 0;
3983 
3984 
3985 exit:
3986 	kfree(criu_svm_md);
3987 	return ret;
3988 }
3989 
3990 int svm_range_get_info(struct kfd_process *p, uint32_t *num_svm_ranges,
3991 		       uint64_t *svm_priv_data_size)
3992 {
3993 	uint64_t total_size, accessibility_size, common_attr_size;
3994 	int nattr_common = 4, nattr_accessibility = 1;
3995 	int num_devices = p->n_pdds;
3996 	struct svm_range_list *svms;
3997 	struct svm_range *prange;
3998 	uint32_t count = 0;
3999 
4000 	*svm_priv_data_size = 0;
4001 
4002 	svms = &p->svms;
4003 	if (!svms)
4004 		return -EINVAL;
4005 
4006 	mutex_lock(&svms->lock);
4007 	list_for_each_entry(prange, &svms->list, list) {
4008 		pr_debug("prange: 0x%p start: 0x%lx\t npages: 0x%llx\t end: 0x%llx\n",
4009 			 prange, prange->start, prange->npages,
4010 			 prange->start + prange->npages - 1);
4011 		count++;
4012 	}
4013 	mutex_unlock(&svms->lock);
4014 
4015 	*num_svm_ranges = count;
4016 	/* Only the accessbility attributes need to be queried for all the gpus
4017 	 * individually, remaining ones are spanned across the entire process
4018 	 * regardless of the various gpu nodes. Of the remaining attributes,
4019 	 * KFD_IOCTL_SVM_ATTR_CLR_FLAGS need not be saved.
4020 	 *
4021 	 * KFD_IOCTL_SVM_ATTR_PREFERRED_LOC
4022 	 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC
4023 	 * KFD_IOCTL_SVM_ATTR_SET_FLAGS
4024 	 * KFD_IOCTL_SVM_ATTR_GRANULARITY
4025 	 *
4026 	 * ** ACCESSBILITY ATTRIBUTES **
4027 	 * (Considered as one, type is altered during query, value is gpuid)
4028 	 * KFD_IOCTL_SVM_ATTR_ACCESS
4029 	 * KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE
4030 	 * KFD_IOCTL_SVM_ATTR_NO_ACCESS
4031 	 */
4032 	if (*num_svm_ranges > 0) {
4033 		common_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4034 			nattr_common;
4035 		accessibility_size = sizeof(struct kfd_ioctl_svm_attribute) *
4036 			nattr_accessibility * num_devices;
4037 
4038 		total_size = sizeof(struct kfd_criu_svm_range_priv_data) +
4039 			common_attr_size + accessibility_size;
4040 
4041 		*svm_priv_data_size = *num_svm_ranges * total_size;
4042 	}
4043 
4044 	pr_debug("num_svm_ranges %u total_priv_size %llu\n", *num_svm_ranges,
4045 		 *svm_priv_data_size);
4046 	return 0;
4047 }
4048 
4049 int kfd_criu_checkpoint_svm(struct kfd_process *p,
4050 			    uint8_t __user *user_priv_data,
4051 			    uint64_t *priv_data_offset)
4052 {
4053 	struct kfd_criu_svm_range_priv_data *svm_priv = NULL;
4054 	struct kfd_ioctl_svm_attribute *query_attr = NULL;
4055 	uint64_t svm_priv_data_size, query_attr_size = 0;
4056 	int index, nattr_common = 4, ret = 0;
4057 	struct svm_range_list *svms;
4058 	int num_devices = p->n_pdds;
4059 	struct svm_range *prange;
4060 	struct mm_struct *mm;
4061 
4062 	svms = &p->svms;
4063 	if (!svms)
4064 		return -EINVAL;
4065 
4066 	mm = get_task_mm(p->lead_thread);
4067 	if (!mm) {
4068 		pr_err("failed to get mm for the target process\n");
4069 		return -ESRCH;
4070 	}
4071 
4072 	query_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4073 				(nattr_common + num_devices);
4074 
4075 	query_attr = kzalloc(query_attr_size, GFP_KERNEL);
4076 	if (!query_attr) {
4077 		ret = -ENOMEM;
4078 		goto exit;
4079 	}
4080 
4081 	query_attr[0].type = KFD_IOCTL_SVM_ATTR_PREFERRED_LOC;
4082 	query_attr[1].type = KFD_IOCTL_SVM_ATTR_PREFETCH_LOC;
4083 	query_attr[2].type = KFD_IOCTL_SVM_ATTR_SET_FLAGS;
4084 	query_attr[3].type = KFD_IOCTL_SVM_ATTR_GRANULARITY;
4085 
4086 	for (index = 0; index < num_devices; index++) {
4087 		struct kfd_process_device *pdd = p->pdds[index];
4088 
4089 		query_attr[index + nattr_common].type =
4090 			KFD_IOCTL_SVM_ATTR_ACCESS;
4091 		query_attr[index + nattr_common].value = pdd->user_gpu_id;
4092 	}
4093 
4094 	svm_priv_data_size = sizeof(*svm_priv) + query_attr_size;
4095 
4096 	svm_priv = kzalloc(svm_priv_data_size, GFP_KERNEL);
4097 	if (!svm_priv) {
4098 		ret = -ENOMEM;
4099 		goto exit_query;
4100 	}
4101 
4102 	index = 0;
4103 	list_for_each_entry(prange, &svms->list, list) {
4104 
4105 		svm_priv->object_type = KFD_CRIU_OBJECT_TYPE_SVM_RANGE;
4106 		svm_priv->start_addr = prange->start;
4107 		svm_priv->size = prange->npages;
4108 		memcpy(&svm_priv->attrs, query_attr, query_attr_size);
4109 		pr_debug("CRIU: prange: 0x%p start: 0x%lx\t npages: 0x%llx end: 0x%llx\t size: 0x%llx\n",
4110 			 prange, prange->start, prange->npages,
4111 			 prange->start + prange->npages - 1,
4112 			 prange->npages * PAGE_SIZE);
4113 
4114 		ret = svm_range_get_attr(p, mm, svm_priv->start_addr,
4115 					 svm_priv->size,
4116 					 (nattr_common + num_devices),
4117 					 svm_priv->attrs);
4118 		if (ret) {
4119 			pr_err("CRIU: failed to obtain range attributes\n");
4120 			goto exit_priv;
4121 		}
4122 
4123 		if (copy_to_user(user_priv_data + *priv_data_offset, svm_priv,
4124 				 svm_priv_data_size)) {
4125 			pr_err("Failed to copy svm priv to user\n");
4126 			ret = -EFAULT;
4127 			goto exit_priv;
4128 		}
4129 
4130 		*priv_data_offset += svm_priv_data_size;
4131 
4132 	}
4133 
4134 
4135 exit_priv:
4136 	kfree(svm_priv);
4137 exit_query:
4138 	kfree(query_attr);
4139 exit:
4140 	mmput(mm);
4141 	return ret;
4142 }
4143 
4144 int
4145 svm_ioctl(struct kfd_process *p, enum kfd_ioctl_svm_op op, uint64_t start,
4146 	  uint64_t size, uint32_t nattrs, struct kfd_ioctl_svm_attribute *attrs)
4147 {
4148 	struct mm_struct *mm = current->mm;
4149 	int r;
4150 
4151 	start >>= PAGE_SHIFT;
4152 	size >>= PAGE_SHIFT;
4153 
4154 	switch (op) {
4155 	case KFD_IOCTL_SVM_OP_SET_ATTR:
4156 		r = svm_range_set_attr(p, mm, start, size, nattrs, attrs);
4157 		break;
4158 	case KFD_IOCTL_SVM_OP_GET_ATTR:
4159 		r = svm_range_get_attr(p, mm, start, size, nattrs, attrs);
4160 		break;
4161 	default:
4162 		r = EINVAL;
4163 		break;
4164 	}
4165 
4166 	return r;
4167 }
4168