xref: /linux/drivers/gpu/drm/amd/amdkfd/kfd_svm.c (revision 44343e8b250abb2f6bfd615493ca07a7f11f3cc2)
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(struct svm_range_list *svms, int32_t *location,
313 				 int32_t *prefetch_loc, uint8_t *granularity,
314 				 uint32_t *flags)
315 {
316 	*location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
317 	*prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
318 	*granularity = svms->default_granularity;
319 	*flags =
320 		KFD_IOCTL_SVM_FLAG_HOST_ACCESS | KFD_IOCTL_SVM_FLAG_COHERENT;
321 }
322 
323 static struct
324 svm_range *svm_range_new(struct svm_range_list *svms, uint64_t start,
325 			 uint64_t last, bool update_mem_usage)
326 {
327 	uint64_t size = last - start + 1;
328 	struct svm_range *prange;
329 	struct kfd_process *p;
330 
331 	prange = kzalloc(sizeof(*prange), GFP_KERNEL);
332 	if (!prange)
333 		return NULL;
334 
335 	p = container_of(svms, struct kfd_process, svms);
336 	if (!p->xnack_enabled && update_mem_usage &&
337 	    amdgpu_amdkfd_reserve_mem_limit(NULL, size << PAGE_SHIFT,
338 				    KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0)) {
339 		pr_info("SVM mapping failed, exceeds resident system memory limit\n");
340 		kfree(prange);
341 		return NULL;
342 	}
343 	prange->npages = size;
344 	prange->svms = svms;
345 	prange->start = start;
346 	prange->last = last;
347 	INIT_LIST_HEAD(&prange->list);
348 	INIT_LIST_HEAD(&prange->update_list);
349 	INIT_LIST_HEAD(&prange->svm_bo_list);
350 	INIT_LIST_HEAD(&prange->deferred_list);
351 	INIT_LIST_HEAD(&prange->child_list);
352 	atomic_set(&prange->invalid, 0);
353 	prange->validate_timestamp = 0;
354 	prange->vram_pages = 0;
355 	mutex_init(&prange->migrate_mutex);
356 	mutex_init(&prange->lock);
357 
358 	if (p->xnack_enabled)
359 		bitmap_copy(prange->bitmap_access, svms->bitmap_supported,
360 			    MAX_GPU_INSTANCE);
361 
362 	svm_range_set_default_attributes(svms, &prange->preferred_loc,
363 					 &prange->prefetch_loc,
364 					 &prange->granularity, &prange->flags);
365 
366 	pr_debug("svms 0x%p [0x%llx 0x%llx]\n", svms, start, last);
367 
368 	return prange;
369 }
370 
371 static bool svm_bo_ref_unless_zero(struct svm_range_bo *svm_bo)
372 {
373 	if (!svm_bo || !kref_get_unless_zero(&svm_bo->kref))
374 		return false;
375 
376 	return true;
377 }
378 
379 static void svm_range_bo_release(struct kref *kref)
380 {
381 	struct svm_range_bo *svm_bo;
382 
383 	svm_bo = container_of(kref, struct svm_range_bo, kref);
384 	pr_debug("svm_bo 0x%p\n", svm_bo);
385 
386 	spin_lock(&svm_bo->list_lock);
387 	while (!list_empty(&svm_bo->range_list)) {
388 		struct svm_range *prange =
389 				list_first_entry(&svm_bo->range_list,
390 						struct svm_range, svm_bo_list);
391 		/* list_del_init tells a concurrent svm_range_vram_node_new when
392 		 * it's safe to reuse the svm_bo pointer and svm_bo_list head.
393 		 */
394 		list_del_init(&prange->svm_bo_list);
395 		spin_unlock(&svm_bo->list_lock);
396 
397 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
398 			 prange->start, prange->last);
399 		mutex_lock(&prange->lock);
400 		prange->svm_bo = NULL;
401 		/* prange should not hold vram page now */
402 		WARN_ONCE(prange->actual_loc, "prange should not hold vram page");
403 		mutex_unlock(&prange->lock);
404 
405 		spin_lock(&svm_bo->list_lock);
406 	}
407 	spin_unlock(&svm_bo->list_lock);
408 
409 	if (mmget_not_zero(svm_bo->eviction_fence->mm)) {
410 		struct kfd_process_device *pdd;
411 		struct kfd_process *p;
412 		struct mm_struct *mm;
413 
414 		mm = svm_bo->eviction_fence->mm;
415 		/*
416 		 * The forked child process takes svm_bo device pages ref, svm_bo could be
417 		 * released after parent process is gone.
418 		 */
419 		p = kfd_lookup_process_by_mm(mm);
420 		if (p) {
421 			pdd = kfd_get_process_device_data(svm_bo->node, p);
422 			if (pdd)
423 				atomic64_sub(amdgpu_bo_size(svm_bo->bo), &pdd->vram_usage);
424 			kfd_unref_process(p);
425 		}
426 		mmput(mm);
427 	}
428 
429 	if (!dma_fence_is_signaled(&svm_bo->eviction_fence->base))
430 		/* We're not in the eviction worker. Signal the fence. */
431 		dma_fence_signal(&svm_bo->eviction_fence->base);
432 	dma_fence_put(&svm_bo->eviction_fence->base);
433 	amdgpu_bo_unref(&svm_bo->bo);
434 	kfree(svm_bo);
435 }
436 
437 static void svm_range_bo_wq_release(struct work_struct *work)
438 {
439 	struct svm_range_bo *svm_bo;
440 
441 	svm_bo = container_of(work, struct svm_range_bo, release_work);
442 	svm_range_bo_release(&svm_bo->kref);
443 }
444 
445 static void svm_range_bo_release_async(struct kref *kref)
446 {
447 	struct svm_range_bo *svm_bo;
448 
449 	svm_bo = container_of(kref, struct svm_range_bo, kref);
450 	pr_debug("svm_bo 0x%p\n", svm_bo);
451 	INIT_WORK(&svm_bo->release_work, svm_range_bo_wq_release);
452 	schedule_work(&svm_bo->release_work);
453 }
454 
455 void svm_range_bo_unref_async(struct svm_range_bo *svm_bo)
456 {
457 	kref_put(&svm_bo->kref, svm_range_bo_release_async);
458 }
459 
460 static void svm_range_bo_unref(struct svm_range_bo *svm_bo)
461 {
462 	if (svm_bo)
463 		kref_put(&svm_bo->kref, svm_range_bo_release);
464 }
465 
466 static bool
467 svm_range_validate_svm_bo(struct kfd_node *node, struct svm_range *prange)
468 {
469 	mutex_lock(&prange->lock);
470 	if (!prange->svm_bo) {
471 		mutex_unlock(&prange->lock);
472 		return false;
473 	}
474 	if (prange->ttm_res) {
475 		/* We still have a reference, all is well */
476 		mutex_unlock(&prange->lock);
477 		return true;
478 	}
479 	if (svm_bo_ref_unless_zero(prange->svm_bo)) {
480 		/*
481 		 * Migrate from GPU to GPU, remove range from source svm_bo->node
482 		 * range list, and return false to allocate svm_bo from destination
483 		 * node.
484 		 */
485 		if (prange->svm_bo->node != node) {
486 			mutex_unlock(&prange->lock);
487 
488 			spin_lock(&prange->svm_bo->list_lock);
489 			list_del_init(&prange->svm_bo_list);
490 			spin_unlock(&prange->svm_bo->list_lock);
491 
492 			svm_range_bo_unref(prange->svm_bo);
493 			return false;
494 		}
495 		if (READ_ONCE(prange->svm_bo->evicting)) {
496 			struct dma_fence *f;
497 			struct svm_range_bo *svm_bo;
498 			/* The BO is getting evicted,
499 			 * we need to get a new one
500 			 */
501 			mutex_unlock(&prange->lock);
502 			svm_bo = prange->svm_bo;
503 			f = dma_fence_get(&svm_bo->eviction_fence->base);
504 			svm_range_bo_unref(prange->svm_bo);
505 			/* wait for the fence to avoid long spin-loop
506 			 * at list_empty_careful
507 			 */
508 			dma_fence_wait(f, false);
509 			dma_fence_put(f);
510 		} else {
511 			/* The BO was still around and we got
512 			 * a new reference to it
513 			 */
514 			mutex_unlock(&prange->lock);
515 			pr_debug("reuse old bo svms 0x%p [0x%lx 0x%lx]\n",
516 				 prange->svms, prange->start, prange->last);
517 
518 			prange->ttm_res = prange->svm_bo->bo->tbo.resource;
519 			return true;
520 		}
521 
522 	} else {
523 		mutex_unlock(&prange->lock);
524 	}
525 
526 	/* We need a new svm_bo. Spin-loop to wait for concurrent
527 	 * svm_range_bo_release to finish removing this range from
528 	 * its range list and set prange->svm_bo to null. After this,
529 	 * it is safe to reuse the svm_bo pointer and svm_bo_list head.
530 	 */
531 	while (!list_empty_careful(&prange->svm_bo_list) || prange->svm_bo)
532 		cond_resched();
533 
534 	return false;
535 }
536 
537 static struct svm_range_bo *svm_range_bo_new(void)
538 {
539 	struct svm_range_bo *svm_bo;
540 
541 	svm_bo = kzalloc(sizeof(*svm_bo), GFP_KERNEL);
542 	if (!svm_bo)
543 		return NULL;
544 
545 	kref_init(&svm_bo->kref);
546 	INIT_LIST_HEAD(&svm_bo->range_list);
547 	spin_lock_init(&svm_bo->list_lock);
548 
549 	return svm_bo;
550 }
551 
552 int
553 svm_range_vram_node_new(struct kfd_node *node, struct svm_range *prange,
554 			bool clear)
555 {
556 	struct kfd_process_device *pdd;
557 	struct amdgpu_bo_param bp;
558 	struct svm_range_bo *svm_bo;
559 	struct amdgpu_bo_user *ubo;
560 	struct amdgpu_bo *bo;
561 	struct kfd_process *p;
562 	struct mm_struct *mm;
563 	int r;
564 
565 	p = container_of(prange->svms, struct kfd_process, svms);
566 	pr_debug("process pid: %d svms 0x%p [0x%lx 0x%lx]\n",
567 		 p->lead_thread->pid, prange->svms,
568 		 prange->start, prange->last);
569 
570 	if (svm_range_validate_svm_bo(node, prange))
571 		return 0;
572 
573 	svm_bo = svm_range_bo_new();
574 	if (!svm_bo) {
575 		pr_debug("failed to alloc svm bo\n");
576 		return -ENOMEM;
577 	}
578 	mm = get_task_mm(p->lead_thread);
579 	if (!mm) {
580 		pr_debug("failed to get mm\n");
581 		kfree(svm_bo);
582 		return -ESRCH;
583 	}
584 	svm_bo->node = node;
585 	svm_bo->eviction_fence =
586 		amdgpu_amdkfd_fence_create(dma_fence_context_alloc(1),
587 					   mm,
588 					   svm_bo);
589 	mmput(mm);
590 	INIT_WORK(&svm_bo->eviction_work, svm_range_evict_svm_bo_worker);
591 	svm_bo->evicting = 0;
592 	memset(&bp, 0, sizeof(bp));
593 	bp.size = prange->npages * PAGE_SIZE;
594 	bp.byte_align = PAGE_SIZE;
595 	bp.domain = AMDGPU_GEM_DOMAIN_VRAM;
596 	bp.flags = AMDGPU_GEM_CREATE_NO_CPU_ACCESS;
597 	bp.flags |= clear ? AMDGPU_GEM_CREATE_VRAM_CLEARED : 0;
598 	bp.flags |= AMDGPU_GEM_CREATE_DISCARDABLE;
599 	bp.type = ttm_bo_type_device;
600 	bp.resv = NULL;
601 	if (node->xcp)
602 		bp.xcp_id_plus1 = node->xcp->id + 1;
603 
604 	r = amdgpu_bo_create_user(node->adev, &bp, &ubo);
605 	if (r) {
606 		pr_debug("failed %d to create bo\n", r);
607 		goto create_bo_failed;
608 	}
609 	bo = &ubo->bo;
610 
611 	pr_debug("alloc bo at offset 0x%lx size 0x%lx on partition %d\n",
612 		 bo->tbo.resource->start << PAGE_SHIFT, bp.size,
613 		 bp.xcp_id_plus1 - 1);
614 
615 	r = amdgpu_bo_reserve(bo, true);
616 	if (r) {
617 		pr_debug("failed %d to reserve bo\n", r);
618 		goto reserve_bo_failed;
619 	}
620 
621 	if (clear) {
622 		r = amdgpu_bo_sync_wait(bo, AMDGPU_FENCE_OWNER_KFD, false);
623 		if (r) {
624 			pr_debug("failed %d to sync bo\n", r);
625 			amdgpu_bo_unreserve(bo);
626 			goto reserve_bo_failed;
627 		}
628 	}
629 
630 	r = dma_resv_reserve_fences(bo->tbo.base.resv, 1);
631 	if (r) {
632 		pr_debug("failed %d to reserve bo\n", r);
633 		amdgpu_bo_unreserve(bo);
634 		goto reserve_bo_failed;
635 	}
636 	amdgpu_bo_fence(bo, &svm_bo->eviction_fence->base, true);
637 
638 	amdgpu_bo_unreserve(bo);
639 
640 	svm_bo->bo = bo;
641 	prange->svm_bo = svm_bo;
642 	prange->ttm_res = bo->tbo.resource;
643 	prange->offset = 0;
644 
645 	spin_lock(&svm_bo->list_lock);
646 	list_add(&prange->svm_bo_list, &svm_bo->range_list);
647 	spin_unlock(&svm_bo->list_lock);
648 
649 	pdd = svm_range_get_pdd_by_node(prange, node);
650 	if (pdd)
651 		atomic64_add(amdgpu_bo_size(bo), &pdd->vram_usage);
652 
653 	return 0;
654 
655 reserve_bo_failed:
656 	amdgpu_bo_unref(&bo);
657 create_bo_failed:
658 	dma_fence_put(&svm_bo->eviction_fence->base);
659 	kfree(svm_bo);
660 	prange->ttm_res = NULL;
661 
662 	return r;
663 }
664 
665 void svm_range_vram_node_free(struct svm_range *prange)
666 {
667 	/* serialize prange->svm_bo unref */
668 	mutex_lock(&prange->lock);
669 	/* prange->svm_bo has not been unref */
670 	if (prange->ttm_res) {
671 		prange->ttm_res = NULL;
672 		mutex_unlock(&prange->lock);
673 		svm_range_bo_unref(prange->svm_bo);
674 	} else
675 		mutex_unlock(&prange->lock);
676 }
677 
678 struct kfd_node *
679 svm_range_get_node_by_id(struct svm_range *prange, uint32_t gpu_id)
680 {
681 	struct kfd_process *p;
682 	struct kfd_process_device *pdd;
683 
684 	p = container_of(prange->svms, struct kfd_process, svms);
685 	pdd = kfd_process_device_data_by_id(p, gpu_id);
686 	if (!pdd) {
687 		pr_debug("failed to get kfd process device by id 0x%x\n", gpu_id);
688 		return NULL;
689 	}
690 
691 	return pdd->dev;
692 }
693 
694 struct kfd_process_device *
695 svm_range_get_pdd_by_node(struct svm_range *prange, struct kfd_node *node)
696 {
697 	struct kfd_process *p;
698 
699 	p = container_of(prange->svms, struct kfd_process, svms);
700 
701 	return kfd_get_process_device_data(node, p);
702 }
703 
704 static int svm_range_bo_validate(void *param, struct amdgpu_bo *bo)
705 {
706 	struct ttm_operation_ctx ctx = { false, false };
707 
708 	amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_VRAM);
709 
710 	return ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
711 }
712 
713 static int
714 svm_range_check_attr(struct kfd_process *p,
715 		     uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
716 {
717 	uint32_t i;
718 
719 	for (i = 0; i < nattr; i++) {
720 		uint32_t val = attrs[i].value;
721 		int gpuidx = MAX_GPU_INSTANCE;
722 
723 		switch (attrs[i].type) {
724 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
725 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM &&
726 			    val != KFD_IOCTL_SVM_LOCATION_UNDEFINED)
727 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
728 			break;
729 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
730 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM)
731 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
732 			break;
733 		case KFD_IOCTL_SVM_ATTR_ACCESS:
734 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
735 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
736 			gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
737 			break;
738 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
739 			break;
740 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
741 			break;
742 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
743 			break;
744 		default:
745 			pr_debug("unknown attr type 0x%x\n", attrs[i].type);
746 			return -EINVAL;
747 		}
748 
749 		if (gpuidx < 0) {
750 			pr_debug("no GPU 0x%x found\n", val);
751 			return -EINVAL;
752 		} else if (gpuidx < MAX_GPU_INSTANCE &&
753 			   !test_bit(gpuidx, p->svms.bitmap_supported)) {
754 			pr_debug("GPU 0x%x not supported\n", val);
755 			return -EINVAL;
756 		}
757 	}
758 
759 	return 0;
760 }
761 
762 static void
763 svm_range_apply_attrs(struct kfd_process *p, struct svm_range *prange,
764 		      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
765 		      bool *update_mapping)
766 {
767 	uint32_t i;
768 	int gpuidx;
769 
770 	for (i = 0; i < nattr; i++) {
771 		switch (attrs[i].type) {
772 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
773 			prange->preferred_loc = attrs[i].value;
774 			break;
775 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
776 			prange->prefetch_loc = attrs[i].value;
777 			break;
778 		case KFD_IOCTL_SVM_ATTR_ACCESS:
779 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
780 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
781 			if (!p->xnack_enabled)
782 				*update_mapping = true;
783 
784 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
785 							       attrs[i].value);
786 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
787 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
788 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
789 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
790 				bitmap_set(prange->bitmap_access, gpuidx, 1);
791 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
792 			} else {
793 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
794 				bitmap_set(prange->bitmap_aip, gpuidx, 1);
795 			}
796 			break;
797 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
798 			*update_mapping = true;
799 			prange->flags |= attrs[i].value;
800 			break;
801 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
802 			*update_mapping = true;
803 			prange->flags &= ~attrs[i].value;
804 			break;
805 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
806 			prange->granularity = min_t(uint32_t, attrs[i].value, 0x3F);
807 			break;
808 		default:
809 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
810 		}
811 	}
812 }
813 
814 static bool
815 svm_range_is_same_attrs(struct kfd_process *p, struct svm_range *prange,
816 			uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
817 {
818 	uint32_t i;
819 	int gpuidx;
820 
821 	for (i = 0; i < nattr; i++) {
822 		switch (attrs[i].type) {
823 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
824 			if (prange->preferred_loc != attrs[i].value)
825 				return false;
826 			break;
827 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
828 			/* Prefetch should always trigger a migration even
829 			 * if the value of the attribute didn't change.
830 			 */
831 			return false;
832 		case KFD_IOCTL_SVM_ATTR_ACCESS:
833 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
834 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
835 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
836 							       attrs[i].value);
837 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
838 				if (test_bit(gpuidx, prange->bitmap_access) ||
839 				    test_bit(gpuidx, prange->bitmap_aip))
840 					return false;
841 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
842 				if (!test_bit(gpuidx, prange->bitmap_access))
843 					return false;
844 			} else {
845 				if (!test_bit(gpuidx, prange->bitmap_aip))
846 					return false;
847 			}
848 			break;
849 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
850 			if ((prange->flags & attrs[i].value) != attrs[i].value)
851 				return false;
852 			break;
853 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
854 			if ((prange->flags & attrs[i].value) != 0)
855 				return false;
856 			break;
857 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
858 			if (prange->granularity != attrs[i].value)
859 				return false;
860 			break;
861 		default:
862 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
863 		}
864 	}
865 
866 	return true;
867 }
868 
869 /**
870  * svm_range_debug_dump - print all range information from svms
871  * @svms: svm range list header
872  *
873  * debug output svm range start, end, prefetch location from svms
874  * interval tree and link list
875  *
876  * Context: The caller must hold svms->lock
877  */
878 static void svm_range_debug_dump(struct svm_range_list *svms)
879 {
880 	struct interval_tree_node *node;
881 	struct svm_range *prange;
882 
883 	pr_debug("dump svms 0x%p list\n", svms);
884 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
885 
886 	list_for_each_entry(prange, &svms->list, list) {
887 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
888 			 prange, prange->start, prange->npages,
889 			 prange->start + prange->npages - 1,
890 			 prange->actual_loc);
891 	}
892 
893 	pr_debug("dump svms 0x%p interval tree\n", svms);
894 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
895 	node = interval_tree_iter_first(&svms->objects, 0, ~0ULL);
896 	while (node) {
897 		prange = container_of(node, struct svm_range, it_node);
898 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
899 			 prange, prange->start, prange->npages,
900 			 prange->start + prange->npages - 1,
901 			 prange->actual_loc);
902 		node = interval_tree_iter_next(node, 0, ~0ULL);
903 	}
904 }
905 
906 static void *
907 svm_range_copy_array(void *psrc, size_t size, uint64_t num_elements,
908 		     uint64_t offset, uint64_t *vram_pages)
909 {
910 	unsigned char *src = (unsigned char *)psrc + offset;
911 	unsigned char *dst;
912 	uint64_t i;
913 
914 	dst = kvmalloc_array(num_elements, size, GFP_KERNEL);
915 	if (!dst)
916 		return NULL;
917 
918 	if (!vram_pages) {
919 		memcpy(dst, src, num_elements * size);
920 		return (void *)dst;
921 	}
922 
923 	*vram_pages = 0;
924 	for (i = 0; i < num_elements; i++) {
925 		dma_addr_t *temp;
926 		temp = (dma_addr_t *)dst + i;
927 		*temp = *((dma_addr_t *)src + i);
928 		if (*temp&SVM_RANGE_VRAM_DOMAIN)
929 			(*vram_pages)++;
930 	}
931 
932 	return (void *)dst;
933 }
934 
935 static int
936 svm_range_copy_dma_addrs(struct svm_range *dst, struct svm_range *src)
937 {
938 	int i;
939 
940 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
941 		if (!src->dma_addr[i])
942 			continue;
943 		dst->dma_addr[i] = svm_range_copy_array(src->dma_addr[i],
944 					sizeof(*src->dma_addr[i]), src->npages, 0, NULL);
945 		if (!dst->dma_addr[i])
946 			return -ENOMEM;
947 	}
948 
949 	return 0;
950 }
951 
952 static int
953 svm_range_split_array(void *ppnew, void *ppold, size_t size,
954 		      uint64_t old_start, uint64_t old_n,
955 		      uint64_t new_start, uint64_t new_n, uint64_t *new_vram_pages)
956 {
957 	unsigned char *new, *old, *pold;
958 	uint64_t d;
959 
960 	if (!ppold)
961 		return 0;
962 	pold = *(unsigned char **)ppold;
963 	if (!pold)
964 		return 0;
965 
966 	d = (new_start - old_start) * size;
967 	/* get dma addr array for new range and calculte its vram page number */
968 	new = svm_range_copy_array(pold, size, new_n, d, new_vram_pages);
969 	if (!new)
970 		return -ENOMEM;
971 	d = (new_start == old_start) ? new_n * size : 0;
972 	old = svm_range_copy_array(pold, size, old_n, d, NULL);
973 	if (!old) {
974 		kvfree(new);
975 		return -ENOMEM;
976 	}
977 	kvfree(pold);
978 	*(void **)ppold = old;
979 	*(void **)ppnew = new;
980 
981 	return 0;
982 }
983 
984 static int
985 svm_range_split_pages(struct svm_range *new, struct svm_range *old,
986 		      uint64_t start, uint64_t last)
987 {
988 	uint64_t npages = last - start + 1;
989 	int i, r;
990 
991 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
992 		r = svm_range_split_array(&new->dma_addr[i], &old->dma_addr[i],
993 					  sizeof(*old->dma_addr[i]), old->start,
994 					  npages, new->start, new->npages,
995 					  old->actual_loc ? &new->vram_pages : NULL);
996 		if (r)
997 			return r;
998 	}
999 	if (old->actual_loc)
1000 		old->vram_pages -= new->vram_pages;
1001 
1002 	return 0;
1003 }
1004 
1005 static int
1006 svm_range_split_nodes(struct svm_range *new, struct svm_range *old,
1007 		      uint64_t start, uint64_t last)
1008 {
1009 	uint64_t npages = last - start + 1;
1010 
1011 	pr_debug("svms 0x%p new prange 0x%p start 0x%lx [0x%llx 0x%llx]\n",
1012 		 new->svms, new, new->start, start, last);
1013 
1014 	if (new->start == old->start) {
1015 		new->offset = old->offset;
1016 		old->offset += new->npages;
1017 	} else {
1018 		new->offset = old->offset + npages;
1019 	}
1020 
1021 	new->svm_bo = svm_range_bo_ref(old->svm_bo);
1022 	new->ttm_res = old->ttm_res;
1023 
1024 	spin_lock(&new->svm_bo->list_lock);
1025 	list_add(&new->svm_bo_list, &new->svm_bo->range_list);
1026 	spin_unlock(&new->svm_bo->list_lock);
1027 
1028 	return 0;
1029 }
1030 
1031 /**
1032  * svm_range_split_adjust - split range and adjust
1033  *
1034  * @new: new range
1035  * @old: the old range
1036  * @start: the old range adjust to start address in pages
1037  * @last: the old range adjust to last address in pages
1038  *
1039  * Copy system memory dma_addr or vram ttm_res in old range to new
1040  * range from new_start up to size new->npages, the remaining old range is from
1041  * start to last
1042  *
1043  * Return:
1044  * 0 - OK, -ENOMEM - out of memory
1045  */
1046 static int
1047 svm_range_split_adjust(struct svm_range *new, struct svm_range *old,
1048 		      uint64_t start, uint64_t last)
1049 {
1050 	int r;
1051 
1052 	pr_debug("svms 0x%p new 0x%lx old [0x%lx 0x%lx] => [0x%llx 0x%llx]\n",
1053 		 new->svms, new->start, old->start, old->last, start, last);
1054 
1055 	if (new->start < old->start ||
1056 	    new->last > old->last) {
1057 		WARN_ONCE(1, "invalid new range start or last\n");
1058 		return -EINVAL;
1059 	}
1060 
1061 	r = svm_range_split_pages(new, old, start, last);
1062 	if (r)
1063 		return r;
1064 
1065 	if (old->actual_loc && old->ttm_res) {
1066 		r = svm_range_split_nodes(new, old, start, last);
1067 		if (r)
1068 			return r;
1069 	}
1070 
1071 	old->npages = last - start + 1;
1072 	old->start = start;
1073 	old->last = last;
1074 	new->flags = old->flags;
1075 	new->preferred_loc = old->preferred_loc;
1076 	new->prefetch_loc = old->prefetch_loc;
1077 	new->actual_loc = old->actual_loc;
1078 	new->granularity = old->granularity;
1079 	new->mapped_to_gpu = old->mapped_to_gpu;
1080 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
1081 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
1082 	atomic_set(&new->queue_refcount, atomic_read(&old->queue_refcount));
1083 
1084 	return 0;
1085 }
1086 
1087 /**
1088  * svm_range_split - split a range in 2 ranges
1089  *
1090  * @prange: the svm range to split
1091  * @start: the remaining range start address in pages
1092  * @last: the remaining range last address in pages
1093  * @new: the result new range generated
1094  *
1095  * Two cases only:
1096  * case 1: if start == prange->start
1097  *         prange ==> prange[start, last]
1098  *         new range [last + 1, prange->last]
1099  *
1100  * case 2: if last == prange->last
1101  *         prange ==> prange[start, last]
1102  *         new range [prange->start, start - 1]
1103  *
1104  * Return:
1105  * 0 - OK, -ENOMEM - out of memory, -EINVAL - invalid start, last
1106  */
1107 static int
1108 svm_range_split(struct svm_range *prange, uint64_t start, uint64_t last,
1109 		struct svm_range **new)
1110 {
1111 	uint64_t old_start = prange->start;
1112 	uint64_t old_last = prange->last;
1113 	struct svm_range_list *svms;
1114 	int r = 0;
1115 
1116 	pr_debug("svms 0x%p [0x%llx 0x%llx] to [0x%llx 0x%llx]\n", prange->svms,
1117 		 old_start, old_last, start, last);
1118 
1119 	if (old_start != start && old_last != last)
1120 		return -EINVAL;
1121 	if (start < old_start || last > old_last)
1122 		return -EINVAL;
1123 
1124 	svms = prange->svms;
1125 	if (old_start == start)
1126 		*new = svm_range_new(svms, last + 1, old_last, false);
1127 	else
1128 		*new = svm_range_new(svms, old_start, start - 1, false);
1129 	if (!*new)
1130 		return -ENOMEM;
1131 
1132 	r = svm_range_split_adjust(*new, prange, start, last);
1133 	if (r) {
1134 		pr_debug("failed %d split [0x%llx 0x%llx] to [0x%llx 0x%llx]\n",
1135 			 r, old_start, old_last, start, last);
1136 		svm_range_free(*new, false);
1137 		*new = NULL;
1138 	}
1139 
1140 	return r;
1141 }
1142 
1143 static int
1144 svm_range_split_tail(struct svm_range *prange, uint64_t new_last,
1145 		     struct list_head *insert_list, struct list_head *remap_list)
1146 {
1147 	struct svm_range *tail = NULL;
1148 	int r = svm_range_split(prange, prange->start, new_last, &tail);
1149 
1150 	if (!r) {
1151 		list_add(&tail->list, insert_list);
1152 		if (!IS_ALIGNED(new_last + 1, 1UL << prange->granularity))
1153 			list_add(&tail->update_list, remap_list);
1154 	}
1155 	return r;
1156 }
1157 
1158 static int
1159 svm_range_split_head(struct svm_range *prange, uint64_t new_start,
1160 		     struct list_head *insert_list, struct list_head *remap_list)
1161 {
1162 	struct svm_range *head = NULL;
1163 	int r = svm_range_split(prange, new_start, prange->last, &head);
1164 
1165 	if (!r) {
1166 		list_add(&head->list, insert_list);
1167 		if (!IS_ALIGNED(new_start, 1UL << prange->granularity))
1168 			list_add(&head->update_list, remap_list);
1169 	}
1170 	return r;
1171 }
1172 
1173 static void
1174 svm_range_add_child(struct svm_range *prange, struct svm_range *pchild, enum svm_work_list_ops op)
1175 {
1176 	pr_debug("add child 0x%p [0x%lx 0x%lx] to prange 0x%p child list %d\n",
1177 		 pchild, pchild->start, pchild->last, prange, op);
1178 
1179 	pchild->work_item.mm = NULL;
1180 	pchild->work_item.op = op;
1181 	list_add_tail(&pchild->child_list, &prange->child_list);
1182 }
1183 
1184 static bool
1185 svm_nodes_in_same_hive(struct kfd_node *node_a, struct kfd_node *node_b)
1186 {
1187 	return (node_a->adev == node_b->adev ||
1188 		amdgpu_xgmi_same_hive(node_a->adev, node_b->adev));
1189 }
1190 
1191 static uint64_t
1192 svm_range_get_pte_flags(struct kfd_node *node, struct amdgpu_vm *vm,
1193 			struct svm_range *prange, int domain)
1194 {
1195 	struct kfd_node *bo_node;
1196 	uint32_t flags = prange->flags;
1197 	uint32_t mapping_flags = 0;
1198 	uint32_t gc_ip_version = KFD_GC_VERSION(node);
1199 	uint64_t pte_flags;
1200 	bool snoop = (domain != SVM_RANGE_VRAM_DOMAIN);
1201 	bool coherent = flags & (KFD_IOCTL_SVM_FLAG_COHERENT | KFD_IOCTL_SVM_FLAG_EXT_COHERENT);
1202 	bool ext_coherent = flags & KFD_IOCTL_SVM_FLAG_EXT_COHERENT;
1203 	unsigned int mtype_local;
1204 
1205 	if (domain == SVM_RANGE_VRAM_DOMAIN)
1206 		bo_node = prange->svm_bo->node;
1207 
1208 	switch (gc_ip_version) {
1209 	case IP_VERSION(9, 4, 1):
1210 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1211 			if (bo_node == node) {
1212 				mapping_flags |= coherent ?
1213 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1214 			} else {
1215 				mapping_flags |= coherent ?
1216 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1217 				if (svm_nodes_in_same_hive(node, bo_node))
1218 					snoop = true;
1219 			}
1220 		} else {
1221 			mapping_flags |= coherent ?
1222 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1223 		}
1224 		break;
1225 	case IP_VERSION(9, 4, 2):
1226 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1227 			if (bo_node == node) {
1228 				mapping_flags |= coherent ?
1229 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1230 				if (node->adev->gmc.xgmi.connected_to_cpu)
1231 					snoop = true;
1232 			} else {
1233 				mapping_flags |= coherent ?
1234 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1235 				if (svm_nodes_in_same_hive(node, bo_node))
1236 					snoop = true;
1237 			}
1238 		} else {
1239 			mapping_flags |= coherent ?
1240 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1241 		}
1242 		break;
1243 	case IP_VERSION(9, 4, 3):
1244 	case IP_VERSION(9, 4, 4):
1245 	case IP_VERSION(9, 5, 0):
1246 		if (ext_coherent)
1247 			mtype_local = AMDGPU_VM_MTYPE_CC;
1248 		else
1249 			mtype_local = amdgpu_mtype_local == 1 ? AMDGPU_VM_MTYPE_NC :
1250 				amdgpu_mtype_local == 2 ? AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1251 		snoop = true;
1252 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1253 			/* local HBM region close to partition */
1254 			if (bo_node->adev == node->adev &&
1255 			    (!bo_node->xcp || !node->xcp || bo_node->xcp->mem_id == node->xcp->mem_id))
1256 				mapping_flags |= mtype_local;
1257 			/* local HBM region far from partition or remote XGMI GPU
1258 			 * with regular system scope coherence
1259 			 */
1260 			else if (svm_nodes_in_same_hive(bo_node, node) && !ext_coherent)
1261 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1262 			/* PCIe P2P on GPUs pre-9.5.0 */
1263 			else if (gc_ip_version < IP_VERSION(9, 5, 0) &&
1264 				 !svm_nodes_in_same_hive(bo_node, node))
1265 				mapping_flags |= AMDGPU_VM_MTYPE_UC;
1266 			/* Other remote memory */
1267 			else
1268 				mapping_flags |= ext_coherent ? AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1269 		/* system memory accessed by the APU */
1270 		} else if (node->adev->flags & AMD_IS_APU) {
1271 			/* On NUMA systems, locality is determined per-page
1272 			 * in amdgpu_gmc_override_vm_pte_flags
1273 			 */
1274 			if (num_possible_nodes() <= 1)
1275 				mapping_flags |= mtype_local;
1276 			else
1277 				mapping_flags |= ext_coherent ? AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1278 		/* system memory accessed by the dGPU */
1279 		} else {
1280 			if (gc_ip_version < IP_VERSION(9, 5, 0) || ext_coherent)
1281 				mapping_flags |= AMDGPU_VM_MTYPE_UC;
1282 			else
1283 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1284 		}
1285 		break;
1286 	case IP_VERSION(12, 0, 0):
1287 	case IP_VERSION(12, 0, 1):
1288 		mapping_flags |= AMDGPU_VM_MTYPE_NC;
1289 		break;
1290 	default:
1291 		mapping_flags |= coherent ?
1292 			AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1293 	}
1294 
1295 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_EXEC)
1296 		mapping_flags |= AMDGPU_VM_PAGE_EXECUTABLE;
1297 
1298 	pte_flags = AMDGPU_PTE_VALID;
1299 	pte_flags |= (domain == SVM_RANGE_VRAM_DOMAIN) ? 0 : AMDGPU_PTE_SYSTEM;
1300 	pte_flags |= snoop ? AMDGPU_PTE_SNOOPED : 0;
1301 	if (gc_ip_version >= IP_VERSION(12, 0, 0))
1302 		pte_flags |= AMDGPU_PTE_IS_PTE;
1303 
1304 	amdgpu_gmc_get_vm_pte(node->adev, vm, NULL, mapping_flags, &pte_flags);
1305 	pte_flags |= AMDGPU_PTE_READABLE;
1306 	if (!(flags & KFD_IOCTL_SVM_FLAG_GPU_RO))
1307 		pte_flags |= AMDGPU_PTE_WRITEABLE;
1308 	return pte_flags;
1309 }
1310 
1311 static int
1312 svm_range_unmap_from_gpu(struct amdgpu_device *adev, struct amdgpu_vm *vm,
1313 			 uint64_t start, uint64_t last,
1314 			 struct dma_fence **fence)
1315 {
1316 	uint64_t init_pte_value = 0;
1317 
1318 	pr_debug("[0x%llx 0x%llx]\n", start, last);
1319 
1320 	return amdgpu_vm_update_range(adev, vm, false, true, true, false, NULL, start,
1321 				      last, init_pte_value, 0, 0, NULL, NULL,
1322 				      fence);
1323 }
1324 
1325 static int
1326 svm_range_unmap_from_gpus(struct svm_range *prange, unsigned long start,
1327 			  unsigned long last, uint32_t trigger)
1328 {
1329 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1330 	struct kfd_process_device *pdd;
1331 	struct dma_fence *fence = NULL;
1332 	struct kfd_process *p;
1333 	uint32_t gpuidx;
1334 	int r = 0;
1335 
1336 	if (!prange->mapped_to_gpu) {
1337 		pr_debug("prange 0x%p [0x%lx 0x%lx] not mapped to GPU\n",
1338 			 prange, prange->start, prange->last);
1339 		return 0;
1340 	}
1341 
1342 	if (prange->start == start && prange->last == last) {
1343 		pr_debug("unmap svms 0x%p prange 0x%p\n", prange->svms, prange);
1344 		prange->mapped_to_gpu = false;
1345 	}
1346 
1347 	bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
1348 		  MAX_GPU_INSTANCE);
1349 	p = container_of(prange->svms, struct kfd_process, svms);
1350 
1351 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1352 		pr_debug("unmap from gpu idx 0x%x\n", gpuidx);
1353 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1354 		if (!pdd) {
1355 			pr_debug("failed to find device idx %d\n", gpuidx);
1356 			return -EINVAL;
1357 		}
1358 
1359 		kfd_smi_event_unmap_from_gpu(pdd->dev, p->lead_thread->pid,
1360 					     start, last, trigger);
1361 
1362 		r = svm_range_unmap_from_gpu(pdd->dev->adev,
1363 					     drm_priv_to_vm(pdd->drm_priv),
1364 					     start, last, &fence);
1365 		if (r)
1366 			break;
1367 
1368 		if (fence) {
1369 			r = dma_fence_wait(fence, false);
1370 			dma_fence_put(fence);
1371 			fence = NULL;
1372 			if (r)
1373 				break;
1374 		}
1375 		kfd_flush_tlb(pdd, TLB_FLUSH_HEAVYWEIGHT);
1376 	}
1377 
1378 	return r;
1379 }
1380 
1381 static int
1382 svm_range_map_to_gpu(struct kfd_process_device *pdd, struct svm_range *prange,
1383 		     unsigned long offset, unsigned long npages, bool readonly,
1384 		     dma_addr_t *dma_addr, struct amdgpu_device *bo_adev,
1385 		     struct dma_fence **fence, bool flush_tlb)
1386 {
1387 	struct amdgpu_device *adev = pdd->dev->adev;
1388 	struct amdgpu_vm *vm = drm_priv_to_vm(pdd->drm_priv);
1389 	uint64_t pte_flags;
1390 	unsigned long last_start;
1391 	int last_domain;
1392 	int r = 0;
1393 	int64_t i, j;
1394 
1395 	last_start = prange->start + offset;
1396 
1397 	pr_debug("svms 0x%p [0x%lx 0x%lx] readonly %d\n", prange->svms,
1398 		 last_start, last_start + npages - 1, readonly);
1399 
1400 	for (i = offset; i < offset + npages; i++) {
1401 		last_domain = dma_addr[i] & SVM_RANGE_VRAM_DOMAIN;
1402 		dma_addr[i] &= ~SVM_RANGE_VRAM_DOMAIN;
1403 
1404 		/* Collect all pages in the same address range and memory domain
1405 		 * that can be mapped with a single call to update mapping.
1406 		 */
1407 		if (i < offset + npages - 1 &&
1408 		    last_domain == (dma_addr[i + 1] & SVM_RANGE_VRAM_DOMAIN))
1409 			continue;
1410 
1411 		pr_debug("Mapping range [0x%lx 0x%llx] on domain: %s\n",
1412 			 last_start, prange->start + i, last_domain ? "GPU" : "CPU");
1413 
1414 		pte_flags = svm_range_get_pte_flags(pdd->dev, vm, prange, last_domain);
1415 		if (readonly)
1416 			pte_flags &= ~AMDGPU_PTE_WRITEABLE;
1417 
1418 		pr_debug("svms 0x%p map [0x%lx 0x%llx] vram %d PTE 0x%llx\n",
1419 			 prange->svms, last_start, prange->start + i,
1420 			 (last_domain == SVM_RANGE_VRAM_DOMAIN) ? 1 : 0,
1421 			 pte_flags);
1422 
1423 		/* For dGPU mode, we use same vm_manager to allocate VRAM for
1424 		 * different memory partition based on fpfn/lpfn, we should use
1425 		 * same vm_manager.vram_base_offset regardless memory partition.
1426 		 */
1427 		r = amdgpu_vm_update_range(adev, vm, false, false, flush_tlb, true,
1428 					   NULL, last_start, prange->start + i,
1429 					   pte_flags,
1430 					   (last_start - prange->start) << PAGE_SHIFT,
1431 					   bo_adev ? bo_adev->vm_manager.vram_base_offset : 0,
1432 					   NULL, dma_addr, &vm->last_update);
1433 
1434 		for (j = last_start - prange->start; j <= i; j++)
1435 			dma_addr[j] |= last_domain;
1436 
1437 		if (r) {
1438 			pr_debug("failed %d to map to gpu 0x%lx\n", r, prange->start);
1439 			goto out;
1440 		}
1441 		last_start = prange->start + i + 1;
1442 	}
1443 
1444 	r = amdgpu_vm_update_pdes(adev, vm, false);
1445 	if (r) {
1446 		pr_debug("failed %d to update directories 0x%lx\n", r,
1447 			 prange->start);
1448 		goto out;
1449 	}
1450 
1451 	if (fence)
1452 		*fence = dma_fence_get(vm->last_update);
1453 
1454 out:
1455 	return r;
1456 }
1457 
1458 static int
1459 svm_range_map_to_gpus(struct svm_range *prange, unsigned long offset,
1460 		      unsigned long npages, bool readonly,
1461 		      unsigned long *bitmap, bool wait, bool flush_tlb)
1462 {
1463 	struct kfd_process_device *pdd;
1464 	struct amdgpu_device *bo_adev = NULL;
1465 	struct kfd_process *p;
1466 	struct dma_fence *fence = NULL;
1467 	uint32_t gpuidx;
1468 	int r = 0;
1469 
1470 	if (prange->svm_bo && prange->ttm_res)
1471 		bo_adev = prange->svm_bo->node->adev;
1472 
1473 	p = container_of(prange->svms, struct kfd_process, svms);
1474 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1475 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
1476 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1477 		if (!pdd) {
1478 			pr_debug("failed to find device idx %d\n", gpuidx);
1479 			return -EINVAL;
1480 		}
1481 
1482 		pdd = kfd_bind_process_to_device(pdd->dev, p);
1483 		if (IS_ERR(pdd))
1484 			return -EINVAL;
1485 
1486 		if (bo_adev && pdd->dev->adev != bo_adev &&
1487 		    !amdgpu_xgmi_same_hive(pdd->dev->adev, bo_adev)) {
1488 			pr_debug("cannot map to device idx %d\n", gpuidx);
1489 			continue;
1490 		}
1491 
1492 		r = svm_range_map_to_gpu(pdd, prange, offset, npages, readonly,
1493 					 prange->dma_addr[gpuidx],
1494 					 bo_adev, wait ? &fence : NULL,
1495 					 flush_tlb);
1496 		if (r)
1497 			break;
1498 
1499 		if (fence) {
1500 			r = dma_fence_wait(fence, false);
1501 			dma_fence_put(fence);
1502 			fence = NULL;
1503 			if (r) {
1504 				pr_debug("failed %d to dma fence wait\n", r);
1505 				break;
1506 			}
1507 		}
1508 
1509 		kfd_flush_tlb(pdd, TLB_FLUSH_LEGACY);
1510 	}
1511 
1512 	return r;
1513 }
1514 
1515 struct svm_validate_context {
1516 	struct kfd_process *process;
1517 	struct svm_range *prange;
1518 	bool intr;
1519 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1520 	struct drm_exec exec;
1521 };
1522 
1523 static int svm_range_reserve_bos(struct svm_validate_context *ctx, bool intr)
1524 {
1525 	struct kfd_process_device *pdd;
1526 	struct amdgpu_vm *vm;
1527 	uint32_t gpuidx;
1528 	int r;
1529 
1530 	drm_exec_init(&ctx->exec, intr ? DRM_EXEC_INTERRUPTIBLE_WAIT: 0, 0);
1531 	drm_exec_until_all_locked(&ctx->exec) {
1532 		for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1533 			pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1534 			if (!pdd) {
1535 				pr_debug("failed to find device idx %d\n", gpuidx);
1536 				r = -EINVAL;
1537 				goto unreserve_out;
1538 			}
1539 			vm = drm_priv_to_vm(pdd->drm_priv);
1540 
1541 			r = amdgpu_vm_lock_pd(vm, &ctx->exec, 2);
1542 			drm_exec_retry_on_contention(&ctx->exec);
1543 			if (unlikely(r)) {
1544 				pr_debug("failed %d to reserve bo\n", r);
1545 				goto unreserve_out;
1546 			}
1547 		}
1548 	}
1549 
1550 	for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1551 		pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1552 		if (!pdd) {
1553 			pr_debug("failed to find device idx %d\n", gpuidx);
1554 			r = -EINVAL;
1555 			goto unreserve_out;
1556 		}
1557 
1558 		r = amdgpu_vm_validate(pdd->dev->adev,
1559 				       drm_priv_to_vm(pdd->drm_priv), NULL,
1560 				       svm_range_bo_validate, NULL);
1561 		if (r) {
1562 			pr_debug("failed %d validate pt bos\n", r);
1563 			goto unreserve_out;
1564 		}
1565 	}
1566 
1567 	return 0;
1568 
1569 unreserve_out:
1570 	drm_exec_fini(&ctx->exec);
1571 	return r;
1572 }
1573 
1574 static void svm_range_unreserve_bos(struct svm_validate_context *ctx)
1575 {
1576 	drm_exec_fini(&ctx->exec);
1577 }
1578 
1579 static void *kfd_svm_page_owner(struct kfd_process *p, int32_t gpuidx)
1580 {
1581 	struct kfd_process_device *pdd;
1582 
1583 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1584 	if (!pdd)
1585 		return NULL;
1586 
1587 	return SVM_ADEV_PGMAP_OWNER(pdd->dev->adev);
1588 }
1589 
1590 /*
1591  * Validation+GPU mapping with concurrent invalidation (MMU notifiers)
1592  *
1593  * To prevent concurrent destruction or change of range attributes, the
1594  * svm_read_lock must be held. The caller must not hold the svm_write_lock
1595  * because that would block concurrent evictions and lead to deadlocks. To
1596  * serialize concurrent migrations or validations of the same range, the
1597  * prange->migrate_mutex must be held.
1598  *
1599  * For VRAM ranges, the SVM BO must be allocated and valid (protected by its
1600  * eviction fence.
1601  *
1602  * The following sequence ensures race-free validation and GPU mapping:
1603  *
1604  * 1. Reserve page table (and SVM BO if range is in VRAM)
1605  * 2. hmm_range_fault to get page addresses (if system memory)
1606  * 3. DMA-map pages (if system memory)
1607  * 4-a. Take notifier lock
1608  * 4-b. Check that pages still valid (mmu_interval_read_retry)
1609  * 4-c. Check that the range was not split or otherwise invalidated
1610  * 4-d. Update GPU page table
1611  * 4.e. Release notifier lock
1612  * 5. Release page table (and SVM BO) reservation
1613  */
1614 static int svm_range_validate_and_map(struct mm_struct *mm,
1615 				      unsigned long map_start, unsigned long map_last,
1616 				      struct svm_range *prange, int32_t gpuidx,
1617 				      bool intr, bool wait, bool flush_tlb)
1618 {
1619 	struct svm_validate_context *ctx;
1620 	unsigned long start, end, addr;
1621 	struct kfd_process *p;
1622 	void *owner;
1623 	int32_t idx;
1624 	int r = 0;
1625 
1626 	ctx = kzalloc(sizeof(struct svm_validate_context), GFP_KERNEL);
1627 	if (!ctx)
1628 		return -ENOMEM;
1629 	ctx->process = container_of(prange->svms, struct kfd_process, svms);
1630 	ctx->prange = prange;
1631 	ctx->intr = intr;
1632 
1633 	if (gpuidx < MAX_GPU_INSTANCE) {
1634 		bitmap_zero(ctx->bitmap, MAX_GPU_INSTANCE);
1635 		bitmap_set(ctx->bitmap, gpuidx, 1);
1636 	} else if (ctx->process->xnack_enabled) {
1637 		bitmap_copy(ctx->bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
1638 
1639 		/* If prefetch range to GPU, or GPU retry fault migrate range to
1640 		 * GPU, which has ACCESS attribute to the range, create mapping
1641 		 * on that GPU.
1642 		 */
1643 		if (prange->actual_loc) {
1644 			gpuidx = kfd_process_gpuidx_from_gpuid(ctx->process,
1645 							prange->actual_loc);
1646 			if (gpuidx < 0) {
1647 				WARN_ONCE(1, "failed get device by id 0x%x\n",
1648 					 prange->actual_loc);
1649 				r = -EINVAL;
1650 				goto free_ctx;
1651 			}
1652 			if (test_bit(gpuidx, prange->bitmap_access))
1653 				bitmap_set(ctx->bitmap, gpuidx, 1);
1654 		}
1655 
1656 		/*
1657 		 * If prange is already mapped or with always mapped flag,
1658 		 * update mapping on GPUs with ACCESS attribute
1659 		 */
1660 		if (bitmap_empty(ctx->bitmap, MAX_GPU_INSTANCE)) {
1661 			if (prange->mapped_to_gpu ||
1662 			    prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)
1663 				bitmap_copy(ctx->bitmap, prange->bitmap_access, MAX_GPU_INSTANCE);
1664 		}
1665 	} else {
1666 		bitmap_or(ctx->bitmap, prange->bitmap_access,
1667 			  prange->bitmap_aip, MAX_GPU_INSTANCE);
1668 	}
1669 
1670 	if (bitmap_empty(ctx->bitmap, MAX_GPU_INSTANCE)) {
1671 		r = 0;
1672 		goto free_ctx;
1673 	}
1674 
1675 	if (prange->actual_loc && !prange->ttm_res) {
1676 		/* This should never happen. actual_loc gets set by
1677 		 * svm_migrate_ram_to_vram after allocating a BO.
1678 		 */
1679 		WARN_ONCE(1, "VRAM BO missing during validation\n");
1680 		r = -EINVAL;
1681 		goto free_ctx;
1682 	}
1683 
1684 	r = svm_range_reserve_bos(ctx, intr);
1685 	if (r)
1686 		goto free_ctx;
1687 
1688 	p = container_of(prange->svms, struct kfd_process, svms);
1689 	owner = kfd_svm_page_owner(p, find_first_bit(ctx->bitmap,
1690 						MAX_GPU_INSTANCE));
1691 	for_each_set_bit(idx, ctx->bitmap, MAX_GPU_INSTANCE) {
1692 		if (kfd_svm_page_owner(p, idx) != owner) {
1693 			owner = NULL;
1694 			break;
1695 		}
1696 	}
1697 
1698 	start = map_start << PAGE_SHIFT;
1699 	end = (map_last + 1) << PAGE_SHIFT;
1700 	for (addr = start; !r && addr < end; ) {
1701 		struct hmm_range *hmm_range = NULL;
1702 		unsigned long map_start_vma;
1703 		unsigned long map_last_vma;
1704 		struct vm_area_struct *vma;
1705 		unsigned long next = 0;
1706 		unsigned long offset;
1707 		unsigned long npages;
1708 		bool readonly;
1709 
1710 		vma = vma_lookup(mm, addr);
1711 		if (vma) {
1712 			readonly = !(vma->vm_flags & VM_WRITE);
1713 
1714 			next = min(vma->vm_end, end);
1715 			npages = (next - addr) >> PAGE_SHIFT;
1716 			/* HMM requires at least READ permissions. If provided with PROT_NONE,
1717 			 * unmap the memory. If it's not already mapped, this is a no-op
1718 			 * If PROT_WRITE is provided without READ, warn first then unmap
1719 			 */
1720 			if (!(vma->vm_flags & VM_READ)) {
1721 				unsigned long e, s;
1722 
1723 				svm_range_lock(prange);
1724 				if (vma->vm_flags & VM_WRITE)
1725 					pr_debug("VM_WRITE without VM_READ is not supported");
1726 				s = max(start, prange->start);
1727 				e = min(end, prange->last);
1728 				if (e >= s)
1729 					r = svm_range_unmap_from_gpus(prange, s, e,
1730 						       KFD_SVM_UNMAP_TRIGGER_UNMAP_FROM_CPU);
1731 				svm_range_unlock(prange);
1732 				/* If unmap returns non-zero, we'll bail on the next for loop
1733 				 * iteration, so just leave r and continue
1734 				 */
1735 				addr = next;
1736 				continue;
1737 			}
1738 
1739 			WRITE_ONCE(p->svms.faulting_task, current);
1740 			r = amdgpu_hmm_range_get_pages(&prange->notifier, addr, npages,
1741 						       readonly, owner, NULL,
1742 						       &hmm_range);
1743 			WRITE_ONCE(p->svms.faulting_task, NULL);
1744 			if (r)
1745 				pr_debug("failed %d to get svm range pages\n", r);
1746 		} else {
1747 			r = -EFAULT;
1748 		}
1749 
1750 		if (!r) {
1751 			offset = (addr >> PAGE_SHIFT) - prange->start;
1752 			r = svm_range_dma_map(prange, ctx->bitmap, offset, npages,
1753 					      hmm_range->hmm_pfns);
1754 			if (r)
1755 				pr_debug("failed %d to dma map range\n", r);
1756 		}
1757 
1758 		svm_range_lock(prange);
1759 
1760 		/* Free backing memory of hmm_range if it was initialized
1761 		 * Overrride return value to TRY AGAIN only if prior returns
1762 		 * were successful
1763 		 */
1764 		if (hmm_range && amdgpu_hmm_range_get_pages_done(hmm_range) && !r) {
1765 			pr_debug("hmm update the range, need validate again\n");
1766 			r = -EAGAIN;
1767 		}
1768 
1769 		if (!r && !list_empty(&prange->child_list)) {
1770 			pr_debug("range split by unmap in parallel, validate again\n");
1771 			r = -EAGAIN;
1772 		}
1773 
1774 		if (!r) {
1775 			map_start_vma = max(map_start, prange->start + offset);
1776 			map_last_vma = min(map_last, prange->start + offset + npages - 1);
1777 			if (map_start_vma <= map_last_vma) {
1778 				offset = map_start_vma - prange->start;
1779 				npages = map_last_vma - map_start_vma + 1;
1780 				r = svm_range_map_to_gpus(prange, offset, npages, readonly,
1781 							  ctx->bitmap, wait, flush_tlb);
1782 			}
1783 		}
1784 
1785 		if (!r && next == end)
1786 			prange->mapped_to_gpu = true;
1787 
1788 		svm_range_unlock(prange);
1789 
1790 		addr = next;
1791 	}
1792 
1793 	svm_range_unreserve_bos(ctx);
1794 	if (!r)
1795 		prange->validate_timestamp = ktime_get_boottime();
1796 
1797 free_ctx:
1798 	kfree(ctx);
1799 
1800 	return r;
1801 }
1802 
1803 /**
1804  * svm_range_list_lock_and_flush_work - flush pending deferred work
1805  *
1806  * @svms: the svm range list
1807  * @mm: the mm structure
1808  *
1809  * Context: Returns with mmap write lock held, pending deferred work flushed
1810  *
1811  */
1812 void
1813 svm_range_list_lock_and_flush_work(struct svm_range_list *svms,
1814 				   struct mm_struct *mm)
1815 {
1816 retry_flush_work:
1817 	flush_work(&svms->deferred_list_work);
1818 	mmap_write_lock(mm);
1819 
1820 	if (list_empty(&svms->deferred_range_list))
1821 		return;
1822 	mmap_write_unlock(mm);
1823 	pr_debug("retry flush\n");
1824 	goto retry_flush_work;
1825 }
1826 
1827 static void svm_range_restore_work(struct work_struct *work)
1828 {
1829 	struct delayed_work *dwork = to_delayed_work(work);
1830 	struct amdkfd_process_info *process_info;
1831 	struct svm_range_list *svms;
1832 	struct svm_range *prange;
1833 	struct kfd_process *p;
1834 	struct mm_struct *mm;
1835 	int evicted_ranges;
1836 	int invalid;
1837 	int r;
1838 
1839 	svms = container_of(dwork, struct svm_range_list, restore_work);
1840 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1841 	if (!evicted_ranges)
1842 		return;
1843 
1844 	pr_debug("restore svm ranges\n");
1845 
1846 	p = container_of(svms, struct kfd_process, svms);
1847 	process_info = p->kgd_process_info;
1848 
1849 	/* Keep mm reference when svm_range_validate_and_map ranges */
1850 	mm = get_task_mm(p->lead_thread);
1851 	if (!mm) {
1852 		pr_debug("svms 0x%p process mm gone\n", svms);
1853 		return;
1854 	}
1855 
1856 	mutex_lock(&process_info->lock);
1857 	svm_range_list_lock_and_flush_work(svms, mm);
1858 	mutex_lock(&svms->lock);
1859 
1860 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1861 
1862 	list_for_each_entry(prange, &svms->list, list) {
1863 		invalid = atomic_read(&prange->invalid);
1864 		if (!invalid)
1865 			continue;
1866 
1867 		pr_debug("restoring svms 0x%p prange 0x%p [0x%lx %lx] inv %d\n",
1868 			 prange->svms, prange, prange->start, prange->last,
1869 			 invalid);
1870 
1871 		/*
1872 		 * If range is migrating, wait for migration is done.
1873 		 */
1874 		mutex_lock(&prange->migrate_mutex);
1875 
1876 		r = svm_range_validate_and_map(mm, prange->start, prange->last, prange,
1877 					       MAX_GPU_INSTANCE, false, true, false);
1878 		if (r)
1879 			pr_debug("failed %d to map 0x%lx to gpus\n", r,
1880 				 prange->start);
1881 
1882 		mutex_unlock(&prange->migrate_mutex);
1883 		if (r)
1884 			goto out_reschedule;
1885 
1886 		if (atomic_cmpxchg(&prange->invalid, invalid, 0) != invalid)
1887 			goto out_reschedule;
1888 	}
1889 
1890 	if (atomic_cmpxchg(&svms->evicted_ranges, evicted_ranges, 0) !=
1891 	    evicted_ranges)
1892 		goto out_reschedule;
1893 
1894 	evicted_ranges = 0;
1895 
1896 	r = kgd2kfd_resume_mm(mm);
1897 	if (r) {
1898 		/* No recovery from this failure. Probably the CP is
1899 		 * hanging. No point trying again.
1900 		 */
1901 		pr_debug("failed %d to resume KFD\n", r);
1902 	}
1903 
1904 	pr_debug("restore svm ranges successfully\n");
1905 
1906 out_reschedule:
1907 	mutex_unlock(&svms->lock);
1908 	mmap_write_unlock(mm);
1909 	mutex_unlock(&process_info->lock);
1910 
1911 	/* If validation failed, reschedule another attempt */
1912 	if (evicted_ranges) {
1913 		pr_debug("reschedule to restore svm range\n");
1914 		queue_delayed_work(system_freezable_wq, &svms->restore_work,
1915 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1916 
1917 		kfd_smi_event_queue_restore_rescheduled(mm);
1918 	}
1919 	mmput(mm);
1920 }
1921 
1922 /**
1923  * svm_range_evict - evict svm range
1924  * @prange: svm range structure
1925  * @mm: current process mm_struct
1926  * @start: starting process queue number
1927  * @last: last process queue number
1928  * @event: mmu notifier event when range is evicted or migrated
1929  *
1930  * Stop all queues of the process to ensure GPU doesn't access the memory, then
1931  * return to let CPU evict the buffer and proceed CPU pagetable update.
1932  *
1933  * Don't need use lock to sync cpu pagetable invalidation with GPU execution.
1934  * If invalidation happens while restore work is running, restore work will
1935  * restart to ensure to get the latest CPU pages mapping to GPU, then start
1936  * the queues.
1937  */
1938 static int
1939 svm_range_evict(struct svm_range *prange, struct mm_struct *mm,
1940 		unsigned long start, unsigned long last,
1941 		enum mmu_notifier_event event)
1942 {
1943 	struct svm_range_list *svms = prange->svms;
1944 	struct svm_range *pchild;
1945 	struct kfd_process *p;
1946 	int r = 0;
1947 
1948 	p = container_of(svms, struct kfd_process, svms);
1949 
1950 	pr_debug("invalidate svms 0x%p prange [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
1951 		 svms, prange->start, prange->last, start, last);
1952 
1953 	if (!p->xnack_enabled ||
1954 	    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) {
1955 		int evicted_ranges;
1956 		bool mapped = prange->mapped_to_gpu;
1957 
1958 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1959 			if (!pchild->mapped_to_gpu)
1960 				continue;
1961 			mapped = true;
1962 			mutex_lock_nested(&pchild->lock, 1);
1963 			if (pchild->start <= last && pchild->last >= start) {
1964 				pr_debug("increment pchild invalid [0x%lx 0x%lx]\n",
1965 					 pchild->start, pchild->last);
1966 				atomic_inc(&pchild->invalid);
1967 			}
1968 			mutex_unlock(&pchild->lock);
1969 		}
1970 
1971 		if (!mapped)
1972 			return r;
1973 
1974 		if (prange->start <= last && prange->last >= start)
1975 			atomic_inc(&prange->invalid);
1976 
1977 		evicted_ranges = atomic_inc_return(&svms->evicted_ranges);
1978 		if (evicted_ranges != 1)
1979 			return r;
1980 
1981 		pr_debug("evicting svms 0x%p range [0x%lx 0x%lx]\n",
1982 			 prange->svms, prange->start, prange->last);
1983 
1984 		/* First eviction, stop the queues */
1985 		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_SVM);
1986 		if (r)
1987 			pr_debug("failed to quiesce KFD\n");
1988 
1989 		pr_debug("schedule to restore svm %p ranges\n", svms);
1990 		queue_delayed_work(system_freezable_wq, &svms->restore_work,
1991 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1992 	} else {
1993 		unsigned long s, l;
1994 		uint32_t trigger;
1995 
1996 		if (event == MMU_NOTIFY_MIGRATE)
1997 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY_MIGRATE;
1998 		else
1999 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY;
2000 
2001 		pr_debug("invalidate unmap svms 0x%p [0x%lx 0x%lx] from GPUs\n",
2002 			 prange->svms, start, last);
2003 		list_for_each_entry(pchild, &prange->child_list, child_list) {
2004 			mutex_lock_nested(&pchild->lock, 1);
2005 			s = max(start, pchild->start);
2006 			l = min(last, pchild->last);
2007 			if (l >= s)
2008 				svm_range_unmap_from_gpus(pchild, s, l, trigger);
2009 			mutex_unlock(&pchild->lock);
2010 		}
2011 		s = max(start, prange->start);
2012 		l = min(last, prange->last);
2013 		if (l >= s)
2014 			svm_range_unmap_from_gpus(prange, s, l, trigger);
2015 	}
2016 
2017 	return r;
2018 }
2019 
2020 static struct svm_range *svm_range_clone(struct svm_range *old)
2021 {
2022 	struct svm_range *new;
2023 
2024 	new = svm_range_new(old->svms, old->start, old->last, false);
2025 	if (!new)
2026 		return NULL;
2027 	if (svm_range_copy_dma_addrs(new, old)) {
2028 		svm_range_free(new, false);
2029 		return NULL;
2030 	}
2031 	if (old->svm_bo) {
2032 		new->ttm_res = old->ttm_res;
2033 		new->offset = old->offset;
2034 		new->svm_bo = svm_range_bo_ref(old->svm_bo);
2035 		spin_lock(&new->svm_bo->list_lock);
2036 		list_add(&new->svm_bo_list, &new->svm_bo->range_list);
2037 		spin_unlock(&new->svm_bo->list_lock);
2038 	}
2039 	new->flags = old->flags;
2040 	new->preferred_loc = old->preferred_loc;
2041 	new->prefetch_loc = old->prefetch_loc;
2042 	new->actual_loc = old->actual_loc;
2043 	new->granularity = old->granularity;
2044 	new->mapped_to_gpu = old->mapped_to_gpu;
2045 	new->vram_pages = old->vram_pages;
2046 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
2047 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
2048 	atomic_set(&new->queue_refcount, atomic_read(&old->queue_refcount));
2049 
2050 	return new;
2051 }
2052 
2053 void svm_range_set_max_pages(struct amdgpu_device *adev)
2054 {
2055 	uint64_t max_pages;
2056 	uint64_t pages, _pages;
2057 	uint64_t min_pages = 0;
2058 	int i, id;
2059 
2060 	for (i = 0; i < adev->kfd.dev->num_nodes; i++) {
2061 		if (adev->kfd.dev->nodes[i]->xcp)
2062 			id = adev->kfd.dev->nodes[i]->xcp->id;
2063 		else
2064 			id = -1;
2065 		pages = KFD_XCP_MEMORY_SIZE(adev, id) >> 17;
2066 		pages = clamp(pages, 1ULL << 9, 1ULL << 18);
2067 		pages = rounddown_pow_of_two(pages);
2068 		min_pages = min_not_zero(min_pages, pages);
2069 	}
2070 
2071 	do {
2072 		max_pages = READ_ONCE(max_svm_range_pages);
2073 		_pages = min_not_zero(max_pages, min_pages);
2074 	} while (cmpxchg(&max_svm_range_pages, max_pages, _pages) != max_pages);
2075 }
2076 
2077 static int
2078 svm_range_split_new(struct svm_range_list *svms, uint64_t start, uint64_t last,
2079 		    uint64_t max_pages, struct list_head *insert_list,
2080 		    struct list_head *update_list)
2081 {
2082 	struct svm_range *prange;
2083 	uint64_t l;
2084 
2085 	pr_debug("max_svm_range_pages 0x%llx adding [0x%llx 0x%llx]\n",
2086 		 max_pages, start, last);
2087 
2088 	while (last >= start) {
2089 		l = min(last, ALIGN_DOWN(start + max_pages, max_pages) - 1);
2090 
2091 		prange = svm_range_new(svms, start, l, true);
2092 		if (!prange)
2093 			return -ENOMEM;
2094 		list_add(&prange->list, insert_list);
2095 		list_add(&prange->update_list, update_list);
2096 
2097 		start = l + 1;
2098 	}
2099 	return 0;
2100 }
2101 
2102 /**
2103  * svm_range_add - add svm range and handle overlap
2104  * @p: the range add to this process svms
2105  * @start: page size aligned
2106  * @size: page size aligned
2107  * @nattr: number of attributes
2108  * @attrs: array of attributes
2109  * @update_list: output, the ranges need validate and update GPU mapping
2110  * @insert_list: output, the ranges need insert to svms
2111  * @remove_list: output, the ranges are replaced and need remove from svms
2112  * @remap_list: output, remap unaligned svm ranges
2113  *
2114  * Check if the virtual address range has overlap with any existing ranges,
2115  * split partly overlapping ranges and add new ranges in the gaps. All changes
2116  * should be applied to the range_list and interval tree transactionally. If
2117  * any range split or allocation fails, the entire update fails. Therefore any
2118  * existing overlapping svm_ranges are cloned and the original svm_ranges left
2119  * unchanged.
2120  *
2121  * If the transaction succeeds, the caller can update and insert clones and
2122  * new ranges, then free the originals.
2123  *
2124  * Otherwise the caller can free the clones and new ranges, while the old
2125  * svm_ranges remain unchanged.
2126  *
2127  * Context: Process context, caller must hold svms->lock
2128  *
2129  * Return:
2130  * 0 - OK, otherwise error code
2131  */
2132 static int
2133 svm_range_add(struct kfd_process *p, uint64_t start, uint64_t size,
2134 	      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
2135 	      struct list_head *update_list, struct list_head *insert_list,
2136 	      struct list_head *remove_list, struct list_head *remap_list)
2137 {
2138 	unsigned long last = start + size - 1UL;
2139 	struct svm_range_list *svms = &p->svms;
2140 	struct interval_tree_node *node;
2141 	struct svm_range *prange;
2142 	struct svm_range *tmp;
2143 	struct list_head new_list;
2144 	int r = 0;
2145 
2146 	pr_debug("svms 0x%p [0x%llx 0x%lx]\n", &p->svms, start, last);
2147 
2148 	INIT_LIST_HEAD(update_list);
2149 	INIT_LIST_HEAD(insert_list);
2150 	INIT_LIST_HEAD(remove_list);
2151 	INIT_LIST_HEAD(&new_list);
2152 	INIT_LIST_HEAD(remap_list);
2153 
2154 	node = interval_tree_iter_first(&svms->objects, start, last);
2155 	while (node) {
2156 		struct interval_tree_node *next;
2157 		unsigned long next_start;
2158 
2159 		pr_debug("found overlap node [0x%lx 0x%lx]\n", node->start,
2160 			 node->last);
2161 
2162 		prange = container_of(node, struct svm_range, it_node);
2163 		next = interval_tree_iter_next(node, start, last);
2164 		next_start = min(node->last, last) + 1;
2165 
2166 		if (svm_range_is_same_attrs(p, prange, nattr, attrs) &&
2167 		    prange->mapped_to_gpu) {
2168 			/* nothing to do */
2169 		} else if (node->start < start || node->last > last) {
2170 			/* node intersects the update range and its attributes
2171 			 * will change. Clone and split it, apply updates only
2172 			 * to the overlapping part
2173 			 */
2174 			struct svm_range *old = prange;
2175 
2176 			prange = svm_range_clone(old);
2177 			if (!prange) {
2178 				r = -ENOMEM;
2179 				goto out;
2180 			}
2181 
2182 			list_add(&old->update_list, remove_list);
2183 			list_add(&prange->list, insert_list);
2184 			list_add(&prange->update_list, update_list);
2185 
2186 			if (node->start < start) {
2187 				pr_debug("change old range start\n");
2188 				r = svm_range_split_head(prange, start,
2189 							 insert_list, remap_list);
2190 				if (r)
2191 					goto out;
2192 			}
2193 			if (node->last > last) {
2194 				pr_debug("change old range last\n");
2195 				r = svm_range_split_tail(prange, last,
2196 							 insert_list, remap_list);
2197 				if (r)
2198 					goto out;
2199 			}
2200 		} else {
2201 			/* The node is contained within start..last,
2202 			 * just update it
2203 			 */
2204 			list_add(&prange->update_list, update_list);
2205 		}
2206 
2207 		/* insert a new node if needed */
2208 		if (node->start > start) {
2209 			r = svm_range_split_new(svms, start, node->start - 1,
2210 						READ_ONCE(max_svm_range_pages),
2211 						&new_list, update_list);
2212 			if (r)
2213 				goto out;
2214 		}
2215 
2216 		node = next;
2217 		start = next_start;
2218 	}
2219 
2220 	/* add a final range at the end if needed */
2221 	if (start <= last)
2222 		r = svm_range_split_new(svms, start, last,
2223 					READ_ONCE(max_svm_range_pages),
2224 					&new_list, update_list);
2225 
2226 out:
2227 	if (r) {
2228 		list_for_each_entry_safe(prange, tmp, insert_list, list)
2229 			svm_range_free(prange, false);
2230 		list_for_each_entry_safe(prange, tmp, &new_list, list)
2231 			svm_range_free(prange, true);
2232 	} else {
2233 		list_splice(&new_list, insert_list);
2234 	}
2235 
2236 	return r;
2237 }
2238 
2239 static void
2240 svm_range_update_notifier_and_interval_tree(struct mm_struct *mm,
2241 					    struct svm_range *prange)
2242 {
2243 	unsigned long start;
2244 	unsigned long last;
2245 
2246 	start = prange->notifier.interval_tree.start >> PAGE_SHIFT;
2247 	last = prange->notifier.interval_tree.last >> PAGE_SHIFT;
2248 
2249 	if (prange->start == start && prange->last == last)
2250 		return;
2251 
2252 	pr_debug("up notifier 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
2253 		  prange->svms, prange, start, last, prange->start,
2254 		  prange->last);
2255 
2256 	if (start != 0 && last != 0) {
2257 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
2258 		svm_range_remove_notifier(prange);
2259 	}
2260 	prange->it_node.start = prange->start;
2261 	prange->it_node.last = prange->last;
2262 
2263 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
2264 	svm_range_add_notifier_locked(mm, prange);
2265 }
2266 
2267 static void
2268 svm_range_handle_list_op(struct svm_range_list *svms, struct svm_range *prange,
2269 			 struct mm_struct *mm)
2270 {
2271 	switch (prange->work_item.op) {
2272 	case SVM_OP_NULL:
2273 		pr_debug("NULL OP 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2274 			 svms, prange, prange->start, prange->last);
2275 		break;
2276 	case SVM_OP_UNMAP_RANGE:
2277 		pr_debug("remove 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2278 			 svms, prange, prange->start, prange->last);
2279 		svm_range_unlink(prange);
2280 		svm_range_remove_notifier(prange);
2281 		svm_range_free(prange, true);
2282 		break;
2283 	case SVM_OP_UPDATE_RANGE_NOTIFIER:
2284 		pr_debug("update notifier 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2285 			 svms, prange, prange->start, prange->last);
2286 		svm_range_update_notifier_and_interval_tree(mm, prange);
2287 		break;
2288 	case SVM_OP_UPDATE_RANGE_NOTIFIER_AND_MAP:
2289 		pr_debug("update and map 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2290 			 svms, prange, prange->start, prange->last);
2291 		svm_range_update_notifier_and_interval_tree(mm, prange);
2292 		/* TODO: implement deferred validation and mapping */
2293 		break;
2294 	case SVM_OP_ADD_RANGE:
2295 		pr_debug("add 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms, prange,
2296 			 prange->start, prange->last);
2297 		svm_range_add_to_svms(prange);
2298 		svm_range_add_notifier_locked(mm, prange);
2299 		break;
2300 	case SVM_OP_ADD_RANGE_AND_MAP:
2301 		pr_debug("add and map 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms,
2302 			 prange, prange->start, prange->last);
2303 		svm_range_add_to_svms(prange);
2304 		svm_range_add_notifier_locked(mm, prange);
2305 		/* TODO: implement deferred validation and mapping */
2306 		break;
2307 	default:
2308 		WARN_ONCE(1, "Unknown prange 0x%p work op %d\n", prange,
2309 			 prange->work_item.op);
2310 	}
2311 }
2312 
2313 static void svm_range_drain_retry_fault(struct svm_range_list *svms)
2314 {
2315 	struct kfd_process_device *pdd;
2316 	struct kfd_process *p;
2317 	uint32_t i;
2318 
2319 	p = container_of(svms, struct kfd_process, svms);
2320 
2321 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2322 		pdd = p->pdds[i];
2323 		if (!pdd)
2324 			continue;
2325 
2326 		pr_debug("drain retry fault gpu %d svms %p\n", i, svms);
2327 
2328 		amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2329 				pdd->dev->adev->irq.retry_cam_enabled ?
2330 				&pdd->dev->adev->irq.ih :
2331 				&pdd->dev->adev->irq.ih1);
2332 
2333 		if (pdd->dev->adev->irq.retry_cam_enabled)
2334 			amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2335 				&pdd->dev->adev->irq.ih_soft);
2336 
2337 
2338 		pr_debug("drain retry fault gpu %d svms 0x%p done\n", i, svms);
2339 	}
2340 }
2341 
2342 static void svm_range_deferred_list_work(struct work_struct *work)
2343 {
2344 	struct svm_range_list *svms;
2345 	struct svm_range *prange;
2346 	struct mm_struct *mm;
2347 
2348 	svms = container_of(work, struct svm_range_list, deferred_list_work);
2349 	pr_debug("enter svms 0x%p\n", svms);
2350 
2351 	spin_lock(&svms->deferred_list_lock);
2352 	while (!list_empty(&svms->deferred_range_list)) {
2353 		prange = list_first_entry(&svms->deferred_range_list,
2354 					  struct svm_range, deferred_list);
2355 		spin_unlock(&svms->deferred_list_lock);
2356 
2357 		pr_debug("prange 0x%p [0x%lx 0x%lx] op %d\n", prange,
2358 			 prange->start, prange->last, prange->work_item.op);
2359 
2360 		mm = prange->work_item.mm;
2361 
2362 		mmap_write_lock(mm);
2363 
2364 		/* Remove from deferred_list must be inside mmap write lock, for
2365 		 * two race cases:
2366 		 * 1. unmap_from_cpu may change work_item.op and add the range
2367 		 *    to deferred_list again, cause use after free bug.
2368 		 * 2. svm_range_list_lock_and_flush_work may hold mmap write
2369 		 *    lock and continue because deferred_list is empty, but
2370 		 *    deferred_list work is actually waiting for mmap lock.
2371 		 */
2372 		spin_lock(&svms->deferred_list_lock);
2373 		list_del_init(&prange->deferred_list);
2374 		spin_unlock(&svms->deferred_list_lock);
2375 
2376 		mutex_lock(&svms->lock);
2377 		mutex_lock(&prange->migrate_mutex);
2378 		while (!list_empty(&prange->child_list)) {
2379 			struct svm_range *pchild;
2380 
2381 			pchild = list_first_entry(&prange->child_list,
2382 						struct svm_range, child_list);
2383 			pr_debug("child prange 0x%p op %d\n", pchild,
2384 				 pchild->work_item.op);
2385 			list_del_init(&pchild->child_list);
2386 			svm_range_handle_list_op(svms, pchild, mm);
2387 		}
2388 		mutex_unlock(&prange->migrate_mutex);
2389 
2390 		svm_range_handle_list_op(svms, prange, mm);
2391 		mutex_unlock(&svms->lock);
2392 		mmap_write_unlock(mm);
2393 
2394 		/* Pairs with mmget in svm_range_add_list_work. If dropping the
2395 		 * last mm refcount, schedule release work to avoid circular locking
2396 		 */
2397 		mmput_async(mm);
2398 
2399 		spin_lock(&svms->deferred_list_lock);
2400 	}
2401 	spin_unlock(&svms->deferred_list_lock);
2402 	pr_debug("exit svms 0x%p\n", svms);
2403 }
2404 
2405 void
2406 svm_range_add_list_work(struct svm_range_list *svms, struct svm_range *prange,
2407 			struct mm_struct *mm, enum svm_work_list_ops op)
2408 {
2409 	spin_lock(&svms->deferred_list_lock);
2410 	/* if prange is on the deferred list */
2411 	if (!list_empty(&prange->deferred_list)) {
2412 		pr_debug("update exist prange 0x%p work op %d\n", prange, op);
2413 		WARN_ONCE(prange->work_item.mm != mm, "unmatch mm\n");
2414 		if (op != SVM_OP_NULL &&
2415 		    prange->work_item.op != SVM_OP_UNMAP_RANGE)
2416 			prange->work_item.op = op;
2417 	} else {
2418 		/* Pairs with mmput in deferred_list_work.
2419 		 * If process is exiting and mm is gone, don't update mmu notifier.
2420 		 */
2421 		if (mmget_not_zero(mm)) {
2422 			prange->work_item.mm = mm;
2423 			prange->work_item.op = op;
2424 			list_add_tail(&prange->deferred_list,
2425 				      &prange->svms->deferred_range_list);
2426 			pr_debug("add prange 0x%p [0x%lx 0x%lx] to work list op %d\n",
2427 				 prange, prange->start, prange->last, op);
2428 		}
2429 	}
2430 	spin_unlock(&svms->deferred_list_lock);
2431 }
2432 
2433 void schedule_deferred_list_work(struct svm_range_list *svms)
2434 {
2435 	spin_lock(&svms->deferred_list_lock);
2436 	if (!list_empty(&svms->deferred_range_list))
2437 		schedule_work(&svms->deferred_list_work);
2438 	spin_unlock(&svms->deferred_list_lock);
2439 }
2440 
2441 static void
2442 svm_range_unmap_split(struct svm_range *parent, struct svm_range *prange, unsigned long start,
2443 		      unsigned long last)
2444 {
2445 	struct svm_range *head;
2446 	struct svm_range *tail;
2447 
2448 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2449 		pr_debug("prange 0x%p [0x%lx 0x%lx] is already freed\n", prange,
2450 			 prange->start, prange->last);
2451 		return;
2452 	}
2453 	if (start > prange->last || last < prange->start)
2454 		return;
2455 
2456 	head = tail = prange;
2457 	if (start > prange->start)
2458 		svm_range_split(prange, prange->start, start - 1, &tail);
2459 	if (last < tail->last)
2460 		svm_range_split(tail, last + 1, tail->last, &head);
2461 
2462 	if (head != prange && tail != prange) {
2463 		svm_range_add_child(parent, head, SVM_OP_UNMAP_RANGE);
2464 		svm_range_add_child(parent, tail, SVM_OP_ADD_RANGE);
2465 	} else if (tail != prange) {
2466 		svm_range_add_child(parent, tail, SVM_OP_UNMAP_RANGE);
2467 	} else if (head != prange) {
2468 		svm_range_add_child(parent, head, SVM_OP_UNMAP_RANGE);
2469 	} else if (parent != prange) {
2470 		prange->work_item.op = SVM_OP_UNMAP_RANGE;
2471 	}
2472 }
2473 
2474 static void
2475 svm_range_unmap_from_cpu(struct mm_struct *mm, struct svm_range *prange,
2476 			 unsigned long start, unsigned long last)
2477 {
2478 	uint32_t trigger = KFD_SVM_UNMAP_TRIGGER_UNMAP_FROM_CPU;
2479 	struct svm_range_list *svms;
2480 	struct svm_range *pchild;
2481 	struct kfd_process *p;
2482 	unsigned long s, l;
2483 	bool unmap_parent;
2484 	uint32_t i;
2485 
2486 	if (atomic_read(&prange->queue_refcount)) {
2487 		int r;
2488 
2489 		pr_warn("Freeing queue vital buffer 0x%lx, queue evicted\n",
2490 			prange->start << PAGE_SHIFT);
2491 		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_SVM);
2492 		if (r)
2493 			pr_debug("failed %d to quiesce KFD queues\n", r);
2494 	}
2495 
2496 	p = kfd_lookup_process_by_mm(mm);
2497 	if (!p)
2498 		return;
2499 	svms = &p->svms;
2500 
2501 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n", svms,
2502 		 prange, prange->start, prange->last, start, last);
2503 
2504 	/* calculate time stamps that are used to decide which page faults need be
2505 	 * dropped or handled before unmap pages from gpu vm
2506 	 */
2507 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2508 		struct kfd_process_device *pdd;
2509 		struct amdgpu_device *adev;
2510 		struct amdgpu_ih_ring *ih;
2511 		uint32_t checkpoint_wptr;
2512 
2513 		pdd = p->pdds[i];
2514 		if (!pdd)
2515 			continue;
2516 
2517 		adev = pdd->dev->adev;
2518 
2519 		/* Check and drain ih1 ring if cam not available */
2520 		if (adev->irq.ih1.ring_size) {
2521 			ih = &adev->irq.ih1;
2522 			checkpoint_wptr = amdgpu_ih_get_wptr(adev, ih);
2523 			if (ih->rptr != checkpoint_wptr) {
2524 				svms->checkpoint_ts[i] =
2525 					amdgpu_ih_decode_iv_ts(adev, ih, checkpoint_wptr, -1);
2526 				continue;
2527 			}
2528 		}
2529 
2530 		/* check if dev->irq.ih_soft is not empty */
2531 		ih = &adev->irq.ih_soft;
2532 		checkpoint_wptr = amdgpu_ih_get_wptr(adev, ih);
2533 		if (ih->rptr != checkpoint_wptr)
2534 			svms->checkpoint_ts[i] = amdgpu_ih_decode_iv_ts(adev, ih, checkpoint_wptr, -1);
2535 	}
2536 
2537 	unmap_parent = start <= prange->start && last >= prange->last;
2538 
2539 	list_for_each_entry(pchild, &prange->child_list, child_list) {
2540 		mutex_lock_nested(&pchild->lock, 1);
2541 		s = max(start, pchild->start);
2542 		l = min(last, pchild->last);
2543 		if (l >= s)
2544 			svm_range_unmap_from_gpus(pchild, s, l, trigger);
2545 		svm_range_unmap_split(prange, pchild, start, last);
2546 		mutex_unlock(&pchild->lock);
2547 	}
2548 	s = max(start, prange->start);
2549 	l = min(last, prange->last);
2550 	if (l >= s)
2551 		svm_range_unmap_from_gpus(prange, s, l, trigger);
2552 	svm_range_unmap_split(prange, prange, start, last);
2553 
2554 	if (unmap_parent)
2555 		svm_range_add_list_work(svms, prange, mm, SVM_OP_UNMAP_RANGE);
2556 	else
2557 		svm_range_add_list_work(svms, prange, mm,
2558 					SVM_OP_UPDATE_RANGE_NOTIFIER);
2559 	schedule_deferred_list_work(svms);
2560 
2561 	kfd_unref_process(p);
2562 }
2563 
2564 /**
2565  * svm_range_cpu_invalidate_pagetables - interval notifier callback
2566  * @mni: mmu_interval_notifier struct
2567  * @range: mmu_notifier_range struct
2568  * @cur_seq: value to pass to mmu_interval_set_seq()
2569  *
2570  * If event is MMU_NOTIFY_UNMAP, this is from CPU unmap range, otherwise, it
2571  * is from migration, or CPU page invalidation callback.
2572  *
2573  * For unmap event, unmap range from GPUs, remove prange from svms in a delayed
2574  * work thread, and split prange if only part of prange is unmapped.
2575  *
2576  * For invalidation event, if GPU retry fault is not enabled, evict the queues,
2577  * then schedule svm_range_restore_work to update GPU mapping and resume queues.
2578  * If GPU retry fault is enabled, unmap the svm range from GPU, retry fault will
2579  * update GPU mapping to recover.
2580  *
2581  * Context: mmap lock, notifier_invalidate_start lock are held
2582  *          for invalidate event, prange lock is held if this is from migration
2583  */
2584 static bool
2585 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
2586 				    const struct mmu_notifier_range *range,
2587 				    unsigned long cur_seq)
2588 {
2589 	struct svm_range *prange;
2590 	unsigned long start;
2591 	unsigned long last;
2592 
2593 	if (range->event == MMU_NOTIFY_RELEASE)
2594 		return true;
2595 
2596 	start = mni->interval_tree.start;
2597 	last = mni->interval_tree.last;
2598 	start = max(start, range->start) >> PAGE_SHIFT;
2599 	last = min(last, range->end - 1) >> PAGE_SHIFT;
2600 	pr_debug("[0x%lx 0x%lx] range[0x%lx 0x%lx] notifier[0x%lx 0x%lx] %d\n",
2601 		 start, last, range->start >> PAGE_SHIFT,
2602 		 (range->end - 1) >> PAGE_SHIFT,
2603 		 mni->interval_tree.start >> PAGE_SHIFT,
2604 		 mni->interval_tree.last >> PAGE_SHIFT, range->event);
2605 
2606 	prange = container_of(mni, struct svm_range, notifier);
2607 
2608 	svm_range_lock(prange);
2609 	mmu_interval_set_seq(mni, cur_seq);
2610 
2611 	switch (range->event) {
2612 	case MMU_NOTIFY_UNMAP:
2613 		svm_range_unmap_from_cpu(mni->mm, prange, start, last);
2614 		break;
2615 	default:
2616 		svm_range_evict(prange, mni->mm, start, last, range->event);
2617 		break;
2618 	}
2619 
2620 	svm_range_unlock(prange);
2621 
2622 	return true;
2623 }
2624 
2625 /**
2626  * svm_range_from_addr - find svm range from fault address
2627  * @svms: svm range list header
2628  * @addr: address to search range interval tree, in pages
2629  * @parent: parent range if range is on child list
2630  *
2631  * Context: The caller must hold svms->lock
2632  *
2633  * Return: the svm_range found or NULL
2634  */
2635 struct svm_range *
2636 svm_range_from_addr(struct svm_range_list *svms, unsigned long addr,
2637 		    struct svm_range **parent)
2638 {
2639 	struct interval_tree_node *node;
2640 	struct svm_range *prange;
2641 	struct svm_range *pchild;
2642 
2643 	node = interval_tree_iter_first(&svms->objects, addr, addr);
2644 	if (!node)
2645 		return NULL;
2646 
2647 	prange = container_of(node, struct svm_range, it_node);
2648 	pr_debug("address 0x%lx prange [0x%lx 0x%lx] node [0x%lx 0x%lx]\n",
2649 		 addr, prange->start, prange->last, node->start, node->last);
2650 
2651 	if (addr >= prange->start && addr <= prange->last) {
2652 		if (parent)
2653 			*parent = prange;
2654 		return prange;
2655 	}
2656 	list_for_each_entry(pchild, &prange->child_list, child_list)
2657 		if (addr >= pchild->start && addr <= pchild->last) {
2658 			pr_debug("found address 0x%lx pchild [0x%lx 0x%lx]\n",
2659 				 addr, pchild->start, pchild->last);
2660 			if (parent)
2661 				*parent = prange;
2662 			return pchild;
2663 		}
2664 
2665 	return NULL;
2666 }
2667 
2668 /* svm_range_best_restore_location - decide the best fault restore location
2669  * @prange: svm range structure
2670  * @adev: the GPU on which vm fault happened
2671  *
2672  * This is only called when xnack is on, to decide the best location to restore
2673  * the range mapping after GPU vm fault. Caller uses the best location to do
2674  * migration if actual loc is not best location, then update GPU page table
2675  * mapping to the best location.
2676  *
2677  * If the preferred loc is accessible by faulting GPU, use preferred loc.
2678  * If vm fault gpu idx is on range ACCESSIBLE bitmap, best_loc is vm fault gpu
2679  * If vm fault gpu idx is on range ACCESSIBLE_IN_PLACE bitmap, then
2680  *    if range actual loc is cpu, best_loc is cpu
2681  *    if vm fault gpu is on xgmi same hive of range actual loc gpu, best_loc is
2682  *    range actual loc.
2683  * Otherwise, GPU no access, best_loc is -1.
2684  *
2685  * Return:
2686  * -1 means vm fault GPU no access
2687  * 0 for CPU or GPU id
2688  */
2689 static int32_t
2690 svm_range_best_restore_location(struct svm_range *prange,
2691 				struct kfd_node *node,
2692 				int32_t *gpuidx)
2693 {
2694 	struct kfd_node *bo_node, *preferred_node;
2695 	struct kfd_process *p;
2696 	uint32_t gpuid;
2697 	int r;
2698 
2699 	p = container_of(prange->svms, struct kfd_process, svms);
2700 
2701 	r = kfd_process_gpuid_from_node(p, node, &gpuid, gpuidx);
2702 	if (r < 0) {
2703 		pr_debug("failed to get gpuid from kgd\n");
2704 		return -1;
2705 	}
2706 
2707 	if (node->adev->apu_prefer_gtt)
2708 		return 0;
2709 
2710 	if (prange->preferred_loc == gpuid ||
2711 	    prange->preferred_loc == KFD_IOCTL_SVM_LOCATION_SYSMEM) {
2712 		return prange->preferred_loc;
2713 	} else if (prange->preferred_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
2714 		preferred_node = svm_range_get_node_by_id(prange, prange->preferred_loc);
2715 		if (preferred_node && svm_nodes_in_same_hive(node, preferred_node))
2716 			return prange->preferred_loc;
2717 		/* fall through */
2718 	}
2719 
2720 	if (test_bit(*gpuidx, prange->bitmap_access))
2721 		return gpuid;
2722 
2723 	if (test_bit(*gpuidx, prange->bitmap_aip)) {
2724 		if (!prange->actual_loc)
2725 			return 0;
2726 
2727 		bo_node = svm_range_get_node_by_id(prange, prange->actual_loc);
2728 		if (bo_node && svm_nodes_in_same_hive(node, bo_node))
2729 			return prange->actual_loc;
2730 		else
2731 			return 0;
2732 	}
2733 
2734 	return -1;
2735 }
2736 
2737 static int
2738 svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
2739 			       unsigned long *start, unsigned long *last,
2740 			       bool *is_heap_stack)
2741 {
2742 	struct vm_area_struct *vma;
2743 	struct interval_tree_node *node;
2744 	struct rb_node *rb_node;
2745 	unsigned long start_limit, end_limit;
2746 
2747 	vma = vma_lookup(p->mm, addr << PAGE_SHIFT);
2748 	if (!vma) {
2749 		pr_debug("VMA does not exist in address [0x%llx]\n", addr);
2750 		return -EFAULT;
2751 	}
2752 
2753 	*is_heap_stack = vma_is_initial_heap(vma) || vma_is_initial_stack(vma);
2754 
2755 	start_limit = max(vma->vm_start >> PAGE_SHIFT,
2756 		      (unsigned long)ALIGN_DOWN(addr, 1UL << p->svms.default_granularity));
2757 	end_limit = min(vma->vm_end >> PAGE_SHIFT,
2758 		    (unsigned long)ALIGN(addr + 1, 1UL << p->svms.default_granularity));
2759 
2760 	/* First range that starts after the fault address */
2761 	node = interval_tree_iter_first(&p->svms.objects, addr + 1, ULONG_MAX);
2762 	if (node) {
2763 		end_limit = min(end_limit, node->start);
2764 		/* Last range that ends before the fault address */
2765 		rb_node = rb_prev(&node->rb);
2766 	} else {
2767 		/* Last range must end before addr because
2768 		 * there was no range after addr
2769 		 */
2770 		rb_node = rb_last(&p->svms.objects.rb_root);
2771 	}
2772 	if (rb_node) {
2773 		node = container_of(rb_node, struct interval_tree_node, rb);
2774 		if (node->last >= addr) {
2775 			WARN(1, "Overlap with prev node and page fault addr\n");
2776 			return -EFAULT;
2777 		}
2778 		start_limit = max(start_limit, node->last + 1);
2779 	}
2780 
2781 	*start = start_limit;
2782 	*last = end_limit - 1;
2783 
2784 	pr_debug("vma [0x%lx 0x%lx] range [0x%lx 0x%lx] is_heap_stack %d\n",
2785 		 vma->vm_start >> PAGE_SHIFT, vma->vm_end >> PAGE_SHIFT,
2786 		 *start, *last, *is_heap_stack);
2787 
2788 	return 0;
2789 }
2790 
2791 static int
2792 svm_range_check_vm_userptr(struct kfd_process *p, uint64_t start, uint64_t last,
2793 			   uint64_t *bo_s, uint64_t *bo_l)
2794 {
2795 	struct amdgpu_bo_va_mapping *mapping;
2796 	struct interval_tree_node *node;
2797 	struct amdgpu_bo *bo = NULL;
2798 	unsigned long userptr;
2799 	uint32_t i;
2800 	int r;
2801 
2802 	for (i = 0; i < p->n_pdds; i++) {
2803 		struct amdgpu_vm *vm;
2804 
2805 		if (!p->pdds[i]->drm_priv)
2806 			continue;
2807 
2808 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
2809 		r = amdgpu_bo_reserve(vm->root.bo, false);
2810 		if (r)
2811 			return r;
2812 
2813 		/* Check userptr by searching entire vm->va interval tree */
2814 		node = interval_tree_iter_first(&vm->va, 0, ~0ULL);
2815 		while (node) {
2816 			mapping = container_of((struct rb_node *)node,
2817 					       struct amdgpu_bo_va_mapping, rb);
2818 			bo = mapping->bo_va->base.bo;
2819 
2820 			if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm,
2821 							 start << PAGE_SHIFT,
2822 							 last << PAGE_SHIFT,
2823 							 &userptr)) {
2824 				node = interval_tree_iter_next(node, 0, ~0ULL);
2825 				continue;
2826 			}
2827 
2828 			pr_debug("[0x%llx 0x%llx] already userptr mapped\n",
2829 				 start, last);
2830 			if (bo_s && bo_l) {
2831 				*bo_s = userptr >> PAGE_SHIFT;
2832 				*bo_l = *bo_s + bo->tbo.ttm->num_pages - 1;
2833 			}
2834 			amdgpu_bo_unreserve(vm->root.bo);
2835 			return -EADDRINUSE;
2836 		}
2837 		amdgpu_bo_unreserve(vm->root.bo);
2838 	}
2839 	return 0;
2840 }
2841 
2842 static struct
2843 svm_range *svm_range_create_unregistered_range(struct kfd_node *node,
2844 						struct kfd_process *p,
2845 						struct mm_struct *mm,
2846 						int64_t addr)
2847 {
2848 	struct svm_range *prange = NULL;
2849 	unsigned long start, last;
2850 	uint32_t gpuid, gpuidx;
2851 	bool is_heap_stack;
2852 	uint64_t bo_s = 0;
2853 	uint64_t bo_l = 0;
2854 	int r;
2855 
2856 	if (svm_range_get_range_boundaries(p, addr, &start, &last,
2857 					   &is_heap_stack))
2858 		return NULL;
2859 
2860 	r = svm_range_check_vm(p, start, last, &bo_s, &bo_l);
2861 	if (r != -EADDRINUSE)
2862 		r = svm_range_check_vm_userptr(p, start, last, &bo_s, &bo_l);
2863 
2864 	if (r == -EADDRINUSE) {
2865 		if (addr >= bo_s && addr <= bo_l)
2866 			return NULL;
2867 
2868 		/* Create one page svm range if 2MB range overlapping */
2869 		start = addr;
2870 		last = addr;
2871 	}
2872 
2873 	prange = svm_range_new(&p->svms, start, last, true);
2874 	if (!prange) {
2875 		pr_debug("Failed to create prange in address [0x%llx]\n", addr);
2876 		return NULL;
2877 	}
2878 	if (kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx)) {
2879 		pr_debug("failed to get gpuid from kgd\n");
2880 		svm_range_free(prange, true);
2881 		return NULL;
2882 	}
2883 
2884 	if (is_heap_stack)
2885 		prange->preferred_loc = KFD_IOCTL_SVM_LOCATION_SYSMEM;
2886 
2887 	svm_range_add_to_svms(prange);
2888 	svm_range_add_notifier_locked(mm, prange);
2889 
2890 	return prange;
2891 }
2892 
2893 /* svm_range_skip_recover - decide if prange can be recovered
2894  * @prange: svm range structure
2895  *
2896  * GPU vm retry fault handle skip recover the range for cases:
2897  * 1. prange is on deferred list to be removed after unmap, it is stale fault,
2898  *    deferred list work will drain the stale fault before free the prange.
2899  * 2. prange is on deferred list to add interval notifier after split, or
2900  * 3. prange is child range, it is split from parent prange, recover later
2901  *    after interval notifier is added.
2902  *
2903  * Return: true to skip recover, false to recover
2904  */
2905 static bool svm_range_skip_recover(struct svm_range *prange)
2906 {
2907 	struct svm_range_list *svms = prange->svms;
2908 
2909 	spin_lock(&svms->deferred_list_lock);
2910 	if (list_empty(&prange->deferred_list) &&
2911 	    list_empty(&prange->child_list)) {
2912 		spin_unlock(&svms->deferred_list_lock);
2913 		return false;
2914 	}
2915 	spin_unlock(&svms->deferred_list_lock);
2916 
2917 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2918 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] unmapped\n",
2919 			 svms, prange, prange->start, prange->last);
2920 		return true;
2921 	}
2922 	if (prange->work_item.op == SVM_OP_ADD_RANGE_AND_MAP ||
2923 	    prange->work_item.op == SVM_OP_ADD_RANGE) {
2924 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] not added yet\n",
2925 			 svms, prange, prange->start, prange->last);
2926 		return true;
2927 	}
2928 	return false;
2929 }
2930 
2931 static void
2932 svm_range_count_fault(struct kfd_node *node, struct kfd_process *p,
2933 		      int32_t gpuidx)
2934 {
2935 	struct kfd_process_device *pdd;
2936 
2937 	/* fault is on different page of same range
2938 	 * or fault is skipped to recover later
2939 	 * or fault is on invalid virtual address
2940 	 */
2941 	if (gpuidx == MAX_GPU_INSTANCE) {
2942 		uint32_t gpuid;
2943 		int r;
2944 
2945 		r = kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx);
2946 		if (r < 0)
2947 			return;
2948 	}
2949 
2950 	/* fault is recovered
2951 	 * or fault cannot recover because GPU no access on the range
2952 	 */
2953 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
2954 	if (pdd)
2955 		WRITE_ONCE(pdd->faults, pdd->faults + 1);
2956 }
2957 
2958 static bool
2959 svm_fault_allowed(struct vm_area_struct *vma, bool write_fault)
2960 {
2961 	unsigned long requested = VM_READ;
2962 
2963 	if (write_fault)
2964 		requested |= VM_WRITE;
2965 
2966 	pr_debug("requested 0x%lx, vma permission flags 0x%lx\n", requested,
2967 		vma->vm_flags);
2968 	return (vma->vm_flags & requested) == requested;
2969 }
2970 
2971 int
2972 svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
2973 			uint32_t vmid, uint32_t node_id,
2974 			uint64_t addr, uint64_t ts, bool write_fault)
2975 {
2976 	unsigned long start, last, size;
2977 	struct mm_struct *mm = NULL;
2978 	struct svm_range_list *svms;
2979 	struct svm_range *prange;
2980 	struct kfd_process *p;
2981 	ktime_t timestamp = ktime_get_boottime();
2982 	struct kfd_node *node;
2983 	int32_t best_loc;
2984 	int32_t gpuid, gpuidx = MAX_GPU_INSTANCE;
2985 	bool write_locked = false;
2986 	struct vm_area_struct *vma;
2987 	bool migration = false;
2988 	int r = 0;
2989 
2990 	if (!KFD_IS_SVM_API_SUPPORTED(adev)) {
2991 		pr_debug("device does not support SVM\n");
2992 		return -EFAULT;
2993 	}
2994 
2995 	p = kfd_lookup_process_by_pasid(pasid, NULL);
2996 	if (!p) {
2997 		pr_debug("kfd process not founded pasid 0x%x\n", pasid);
2998 		return 0;
2999 	}
3000 	svms = &p->svms;
3001 
3002 	pr_debug("restoring svms 0x%p fault address 0x%llx\n", svms, addr);
3003 
3004 	if (atomic_read(&svms->drain_pagefaults)) {
3005 		pr_debug("page fault handling disabled, drop fault 0x%llx\n", addr);
3006 		r = 0;
3007 		goto out;
3008 	}
3009 
3010 	node = kfd_node_by_irq_ids(adev, node_id, vmid);
3011 	if (!node) {
3012 		pr_debug("kfd node does not exist node_id: %d, vmid: %d\n", node_id,
3013 			 vmid);
3014 		r = -EFAULT;
3015 		goto out;
3016 	}
3017 
3018 	if (kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx)) {
3019 		pr_debug("failed to get gpuid/gpuidex for node_id: %d\n", node_id);
3020 		r = -EFAULT;
3021 		goto out;
3022 	}
3023 
3024 	if (!p->xnack_enabled) {
3025 		pr_debug("XNACK not enabled for pasid 0x%x\n", pasid);
3026 		r = -EFAULT;
3027 		goto out;
3028 	}
3029 
3030 	/* p->lead_thread is available as kfd_process_wq_release flush the work
3031 	 * before releasing task ref.
3032 	 */
3033 	mm = get_task_mm(p->lead_thread);
3034 	if (!mm) {
3035 		pr_debug("svms 0x%p failed to get mm\n", svms);
3036 		r = 0;
3037 		goto out;
3038 	}
3039 
3040 	mmap_read_lock(mm);
3041 retry_write_locked:
3042 	mutex_lock(&svms->lock);
3043 
3044 	/* check if this page fault time stamp is before svms->checkpoint_ts */
3045 	if (svms->checkpoint_ts[gpuidx] != 0) {
3046 		if (amdgpu_ih_ts_after_or_equal(ts,  svms->checkpoint_ts[gpuidx])) {
3047 			pr_debug("draining retry fault, drop fault 0x%llx\n", addr);
3048 			r = -EAGAIN;
3049 			goto out_unlock_svms;
3050 		} else {
3051 			/* ts is after svms->checkpoint_ts now, reset svms->checkpoint_ts
3052 			 * to zero to avoid following ts wrap around give wrong comparing
3053 			 */
3054 			svms->checkpoint_ts[gpuidx] = 0;
3055 		}
3056 	}
3057 
3058 	prange = svm_range_from_addr(svms, addr, NULL);
3059 	if (!prange) {
3060 		pr_debug("failed to find prange svms 0x%p address [0x%llx]\n",
3061 			 svms, addr);
3062 		if (!write_locked) {
3063 			/* Need the write lock to create new range with MMU notifier.
3064 			 * Also flush pending deferred work to make sure the interval
3065 			 * tree is up to date before we add a new range
3066 			 */
3067 			mutex_unlock(&svms->lock);
3068 			mmap_read_unlock(mm);
3069 			mmap_write_lock(mm);
3070 			write_locked = true;
3071 			goto retry_write_locked;
3072 		}
3073 		prange = svm_range_create_unregistered_range(node, p, mm, addr);
3074 		if (!prange) {
3075 			pr_debug("failed to create unregistered range svms 0x%p address [0x%llx]\n",
3076 				 svms, addr);
3077 			mmap_write_downgrade(mm);
3078 			r = -EFAULT;
3079 			goto out_unlock_svms;
3080 		}
3081 	}
3082 	if (write_locked)
3083 		mmap_write_downgrade(mm);
3084 
3085 	mutex_lock(&prange->migrate_mutex);
3086 
3087 	if (svm_range_skip_recover(prange)) {
3088 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
3089 		r = 0;
3090 		goto out_unlock_range;
3091 	}
3092 
3093 	/* skip duplicate vm fault on different pages of same range */
3094 	if (ktime_before(timestamp, ktime_add_ns(prange->validate_timestamp,
3095 				AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING))) {
3096 		pr_debug("svms 0x%p [0x%lx %lx] already restored\n",
3097 			 svms, prange->start, prange->last);
3098 		r = 0;
3099 		goto out_unlock_range;
3100 	}
3101 
3102 	/* __do_munmap removed VMA, return success as we are handling stale
3103 	 * retry fault.
3104 	 */
3105 	vma = vma_lookup(mm, addr << PAGE_SHIFT);
3106 	if (!vma) {
3107 		pr_debug("address 0x%llx VMA is removed\n", addr);
3108 		r = 0;
3109 		goto out_unlock_range;
3110 	}
3111 
3112 	if (!svm_fault_allowed(vma, write_fault)) {
3113 		pr_debug("fault addr 0x%llx no %s permission\n", addr,
3114 			write_fault ? "write" : "read");
3115 		r = -EPERM;
3116 		goto out_unlock_range;
3117 	}
3118 
3119 	best_loc = svm_range_best_restore_location(prange, node, &gpuidx);
3120 	if (best_loc == -1) {
3121 		pr_debug("svms %p failed get best restore loc [0x%lx 0x%lx]\n",
3122 			 svms, prange->start, prange->last);
3123 		r = -EACCES;
3124 		goto out_unlock_range;
3125 	}
3126 
3127 	pr_debug("svms %p [0x%lx 0x%lx] best restore 0x%x, actual loc 0x%x\n",
3128 		 svms, prange->start, prange->last, best_loc,
3129 		 prange->actual_loc);
3130 
3131 	kfd_smi_event_page_fault_start(node, p->lead_thread->pid, addr,
3132 				       write_fault, timestamp);
3133 
3134 	/* Align migration range start and size to granularity size */
3135 	size = 1UL << prange->granularity;
3136 	start = max_t(unsigned long, ALIGN_DOWN(addr, size), prange->start);
3137 	last = min_t(unsigned long, ALIGN(addr + 1, size) - 1, prange->last);
3138 	if (prange->actual_loc != 0 || best_loc != 0) {
3139 		if (best_loc) {
3140 			r = svm_migrate_to_vram(prange, best_loc, start, last,
3141 					mm, KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU);
3142 			if (r) {
3143 				pr_debug("svm_migrate_to_vram failed (%d) at %llx, falling back to system memory\n",
3144 					 r, addr);
3145 				/* Fallback to system memory if migration to
3146 				 * VRAM failed
3147 				 */
3148 				if (prange->actual_loc && prange->actual_loc != best_loc)
3149 					r = svm_migrate_vram_to_ram(prange, mm, start, last,
3150 						KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU, NULL);
3151 				else
3152 					r = 0;
3153 			}
3154 		} else {
3155 			r = svm_migrate_vram_to_ram(prange, mm, start, last,
3156 					KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU, NULL);
3157 		}
3158 		if (r) {
3159 			pr_debug("failed %d to migrate svms %p [0x%lx 0x%lx]\n",
3160 				 r, svms, start, last);
3161 			goto out_migrate_fail;
3162 		} else {
3163 			migration = true;
3164 		}
3165 	}
3166 
3167 	r = svm_range_validate_and_map(mm, start, last, prange, gpuidx, false,
3168 				       false, false);
3169 	if (r)
3170 		pr_debug("failed %d to map svms 0x%p [0x%lx 0x%lx] to gpus\n",
3171 			 r, svms, start, last);
3172 
3173 out_migrate_fail:
3174 	kfd_smi_event_page_fault_end(node, p->lead_thread->pid, addr,
3175 				     migration);
3176 
3177 out_unlock_range:
3178 	mutex_unlock(&prange->migrate_mutex);
3179 out_unlock_svms:
3180 	mutex_unlock(&svms->lock);
3181 	mmap_read_unlock(mm);
3182 
3183 	if (r != -EAGAIN)
3184 		svm_range_count_fault(node, p, gpuidx);
3185 
3186 	mmput(mm);
3187 out:
3188 	kfd_unref_process(p);
3189 
3190 	if (r == -EAGAIN) {
3191 		pr_debug("recover vm fault later\n");
3192 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
3193 		r = 0;
3194 	}
3195 	return r;
3196 }
3197 
3198 int
3199 svm_range_switch_xnack_reserve_mem(struct kfd_process *p, bool xnack_enabled)
3200 {
3201 	struct svm_range *prange, *pchild;
3202 	uint64_t reserved_size = 0;
3203 	uint64_t size;
3204 	int r = 0;
3205 
3206 	pr_debug("switching xnack from %d to %d\n", p->xnack_enabled, xnack_enabled);
3207 
3208 	mutex_lock(&p->svms.lock);
3209 
3210 	list_for_each_entry(prange, &p->svms.list, list) {
3211 		svm_range_lock(prange);
3212 		list_for_each_entry(pchild, &prange->child_list, child_list) {
3213 			size = (pchild->last - pchild->start + 1) << PAGE_SHIFT;
3214 			if (xnack_enabled) {
3215 				amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3216 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3217 			} else {
3218 				r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3219 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3220 				if (r)
3221 					goto out_unlock;
3222 				reserved_size += size;
3223 			}
3224 		}
3225 
3226 		size = (prange->last - prange->start + 1) << PAGE_SHIFT;
3227 		if (xnack_enabled) {
3228 			amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3229 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3230 		} else {
3231 			r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3232 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3233 			if (r)
3234 				goto out_unlock;
3235 			reserved_size += size;
3236 		}
3237 out_unlock:
3238 		svm_range_unlock(prange);
3239 		if (r)
3240 			break;
3241 	}
3242 
3243 	if (r)
3244 		amdgpu_amdkfd_unreserve_mem_limit(NULL, reserved_size,
3245 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3246 	else
3247 		/* Change xnack mode must be inside svms lock, to avoid race with
3248 		 * svm_range_deferred_list_work unreserve memory in parallel.
3249 		 */
3250 		p->xnack_enabled = xnack_enabled;
3251 
3252 	mutex_unlock(&p->svms.lock);
3253 	return r;
3254 }
3255 
3256 void svm_range_list_fini(struct kfd_process *p)
3257 {
3258 	struct svm_range *prange;
3259 	struct svm_range *next;
3260 
3261 	pr_debug("process pid %d svms 0x%p\n", p->lead_thread->pid,
3262 		 &p->svms);
3263 
3264 	cancel_delayed_work_sync(&p->svms.restore_work);
3265 
3266 	/* Ensure list work is finished before process is destroyed */
3267 	flush_work(&p->svms.deferred_list_work);
3268 
3269 	/*
3270 	 * Ensure no retry fault comes in afterwards, as page fault handler will
3271 	 * not find kfd process and take mm lock to recover fault.
3272 	 * stop kfd page fault handing, then wait pending page faults got drained
3273 	 */
3274 	atomic_set(&p->svms.drain_pagefaults, 1);
3275 	svm_range_drain_retry_fault(&p->svms);
3276 
3277 	list_for_each_entry_safe(prange, next, &p->svms.list, list) {
3278 		svm_range_unlink(prange);
3279 		svm_range_remove_notifier(prange);
3280 		svm_range_free(prange, true);
3281 	}
3282 
3283 	mutex_destroy(&p->svms.lock);
3284 
3285 	pr_debug("process pid %d svms 0x%p done\n",
3286 		p->lead_thread->pid, &p->svms);
3287 }
3288 
3289 int svm_range_list_init(struct kfd_process *p)
3290 {
3291 	struct svm_range_list *svms = &p->svms;
3292 	int i;
3293 
3294 	svms->objects = RB_ROOT_CACHED;
3295 	mutex_init(&svms->lock);
3296 	INIT_LIST_HEAD(&svms->list);
3297 	atomic_set(&svms->evicted_ranges, 0);
3298 	atomic_set(&svms->drain_pagefaults, 0);
3299 	INIT_DELAYED_WORK(&svms->restore_work, svm_range_restore_work);
3300 	INIT_WORK(&svms->deferred_list_work, svm_range_deferred_list_work);
3301 	INIT_LIST_HEAD(&svms->deferred_range_list);
3302 	INIT_LIST_HEAD(&svms->criu_svm_metadata_list);
3303 	spin_lock_init(&svms->deferred_list_lock);
3304 
3305 	for (i = 0; i < p->n_pdds; i++)
3306 		if (KFD_IS_SVM_API_SUPPORTED(p->pdds[i]->dev->adev))
3307 			bitmap_set(svms->bitmap_supported, i, 1);
3308 
3309 	 /* Value of default granularity cannot exceed 0x1B, the
3310 	  * number of pages supported by a 4-level paging table
3311 	  */
3312 	svms->default_granularity = min_t(u8, amdgpu_svm_default_granularity, 0x1B);
3313 	pr_debug("Default SVM Granularity to use: %d\n", svms->default_granularity);
3314 
3315 	return 0;
3316 }
3317 
3318 /**
3319  * svm_range_check_vm - check if virtual address range mapped already
3320  * @p: current kfd_process
3321  * @start: range start address, in pages
3322  * @last: range last address, in pages
3323  * @bo_s: mapping start address in pages if address range already mapped
3324  * @bo_l: mapping last address in pages if address range already mapped
3325  *
3326  * The purpose is to avoid virtual address ranges already allocated by
3327  * kfd_ioctl_alloc_memory_of_gpu ioctl.
3328  * It looks for each pdd in the kfd_process.
3329  *
3330  * Context: Process context
3331  *
3332  * Return 0 - OK, if the range is not mapped.
3333  * Otherwise error code:
3334  * -EADDRINUSE - if address is mapped already by kfd_ioctl_alloc_memory_of_gpu
3335  * -ERESTARTSYS - A wait for the buffer to become unreserved was interrupted by
3336  * a signal. Release all buffer reservations and return to user-space.
3337  */
3338 static int
3339 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
3340 		   uint64_t *bo_s, uint64_t *bo_l)
3341 {
3342 	struct amdgpu_bo_va_mapping *mapping;
3343 	struct interval_tree_node *node;
3344 	uint32_t i;
3345 	int r;
3346 
3347 	for (i = 0; i < p->n_pdds; i++) {
3348 		struct amdgpu_vm *vm;
3349 
3350 		if (!p->pdds[i]->drm_priv)
3351 			continue;
3352 
3353 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
3354 		r = amdgpu_bo_reserve(vm->root.bo, false);
3355 		if (r)
3356 			return r;
3357 
3358 		node = interval_tree_iter_first(&vm->va, start, last);
3359 		if (node) {
3360 			pr_debug("range [0x%llx 0x%llx] already TTM mapped\n",
3361 				 start, last);
3362 			mapping = container_of((struct rb_node *)node,
3363 					       struct amdgpu_bo_va_mapping, rb);
3364 			if (bo_s && bo_l) {
3365 				*bo_s = mapping->start;
3366 				*bo_l = mapping->last;
3367 			}
3368 			amdgpu_bo_unreserve(vm->root.bo);
3369 			return -EADDRINUSE;
3370 		}
3371 		amdgpu_bo_unreserve(vm->root.bo);
3372 	}
3373 
3374 	return 0;
3375 }
3376 
3377 /**
3378  * svm_range_is_valid - check if virtual address range is valid
3379  * @p: current kfd_process
3380  * @start: range start address, in pages
3381  * @size: range size, in pages
3382  *
3383  * Valid virtual address range means it belongs to one or more VMAs
3384  *
3385  * Context: Process context
3386  *
3387  * Return:
3388  *  0 - OK, otherwise error code
3389  */
3390 static int
3391 svm_range_is_valid(struct kfd_process *p, uint64_t start, uint64_t size)
3392 {
3393 	const unsigned long device_vma = VM_IO | VM_PFNMAP | VM_MIXEDMAP;
3394 	struct vm_area_struct *vma;
3395 	unsigned long end;
3396 	unsigned long start_unchg = start;
3397 
3398 	start <<= PAGE_SHIFT;
3399 	end = start + (size << PAGE_SHIFT);
3400 	do {
3401 		vma = vma_lookup(p->mm, start);
3402 		if (!vma || (vma->vm_flags & device_vma))
3403 			return -EFAULT;
3404 		start = min(end, vma->vm_end);
3405 	} while (start < end);
3406 
3407 	return svm_range_check_vm(p, start_unchg, (end - 1) >> PAGE_SHIFT, NULL,
3408 				  NULL);
3409 }
3410 
3411 /**
3412  * svm_range_best_prefetch_location - decide the best prefetch location
3413  * @prange: svm range structure
3414  *
3415  * For xnack off:
3416  * If range map to single GPU, the best prefetch location is prefetch_loc, which
3417  * can be CPU or GPU.
3418  *
3419  * If range is ACCESS or ACCESS_IN_PLACE by mGPUs, only if mGPU connection on
3420  * XGMI same hive, the best prefetch location is prefetch_loc GPU, othervise
3421  * the best prefetch location is always CPU, because GPU can not have coherent
3422  * mapping VRAM of other GPUs even with large-BAR PCIe connection.
3423  *
3424  * For xnack on:
3425  * If range is not ACCESS_IN_PLACE by mGPUs, the best prefetch location is
3426  * prefetch_loc, other GPU access will generate vm fault and trigger migration.
3427  *
3428  * If range is ACCESS_IN_PLACE by mGPUs, only if mGPU connection on XGMI same
3429  * hive, the best prefetch location is prefetch_loc GPU, otherwise the best
3430  * prefetch location is always CPU.
3431  *
3432  * Context: Process context
3433  *
3434  * Return:
3435  * 0 for CPU or GPU id
3436  */
3437 static uint32_t
3438 svm_range_best_prefetch_location(struct svm_range *prange)
3439 {
3440 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
3441 	uint32_t best_loc = prange->prefetch_loc;
3442 	struct kfd_process_device *pdd;
3443 	struct kfd_node *bo_node;
3444 	struct kfd_process *p;
3445 	uint32_t gpuidx;
3446 
3447 	p = container_of(prange->svms, struct kfd_process, svms);
3448 
3449 	if (!best_loc || best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED)
3450 		goto out;
3451 
3452 	bo_node = svm_range_get_node_by_id(prange, best_loc);
3453 	if (!bo_node) {
3454 		WARN_ONCE(1, "failed to get valid kfd node at id%x\n", best_loc);
3455 		best_loc = 0;
3456 		goto out;
3457 	}
3458 
3459 	if (bo_node->adev->apu_prefer_gtt) {
3460 		best_loc = 0;
3461 		goto out;
3462 	}
3463 
3464 	if (p->xnack_enabled)
3465 		bitmap_copy(bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
3466 	else
3467 		bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
3468 			  MAX_GPU_INSTANCE);
3469 
3470 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
3471 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
3472 		if (!pdd) {
3473 			pr_debug("failed to get device by idx 0x%x\n", gpuidx);
3474 			continue;
3475 		}
3476 
3477 		if (pdd->dev->adev == bo_node->adev)
3478 			continue;
3479 
3480 		if (!svm_nodes_in_same_hive(pdd->dev, bo_node)) {
3481 			best_loc = 0;
3482 			break;
3483 		}
3484 	}
3485 
3486 out:
3487 	pr_debug("xnack %d svms 0x%p [0x%lx 0x%lx] best loc 0x%x\n",
3488 		 p->xnack_enabled, &p->svms, prange->start, prange->last,
3489 		 best_loc);
3490 
3491 	return best_loc;
3492 }
3493 
3494 /* svm_range_trigger_migration - start page migration if prefetch loc changed
3495  * @mm: current process mm_struct
3496  * @prange: svm range structure
3497  * @migrated: output, true if migration is triggered
3498  *
3499  * If range perfetch_loc is GPU, actual loc is cpu 0, then migrate the range
3500  * from ram to vram.
3501  * If range prefetch_loc is cpu 0, actual loc is GPU, then migrate the range
3502  * from vram to ram.
3503  *
3504  * If GPU vm fault retry is not enabled, migration interact with MMU notifier
3505  * and restore work:
3506  * 1. migrate_vma_setup invalidate pages, MMU notifier callback svm_range_evict
3507  *    stops all queues, schedule restore work
3508  * 2. svm_range_restore_work wait for migration is done by
3509  *    a. svm_range_validate_vram takes prange->migrate_mutex
3510  *    b. svm_range_validate_ram HMM get pages wait for CPU fault handle returns
3511  * 3. restore work update mappings of GPU, resume all queues.
3512  *
3513  * Context: Process context
3514  *
3515  * Return:
3516  * 0 - OK, otherwise - error code of migration
3517  */
3518 static int
3519 svm_range_trigger_migration(struct mm_struct *mm, struct svm_range *prange,
3520 			    bool *migrated)
3521 {
3522 	uint32_t best_loc;
3523 	int r = 0;
3524 
3525 	*migrated = false;
3526 	best_loc = svm_range_best_prefetch_location(prange);
3527 
3528 	/* when best_loc is a gpu node and same as prange->actual_loc
3529 	 * we still need do migration as prange->actual_loc !=0 does
3530 	 * not mean all pages in prange are vram. hmm migrate will pick
3531 	 * up right pages during migration.
3532 	 */
3533 	if ((best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED) ||
3534 	    (best_loc == 0 && prange->actual_loc == 0))
3535 		return 0;
3536 
3537 	if (!best_loc) {
3538 		r = svm_migrate_vram_to_ram(prange, mm, prange->start, prange->last,
3539 					KFD_MIGRATE_TRIGGER_PREFETCH, NULL);
3540 		*migrated = !r;
3541 		return r;
3542 	}
3543 
3544 	r = svm_migrate_to_vram(prange, best_loc, prange->start, prange->last,
3545 				mm, KFD_MIGRATE_TRIGGER_PREFETCH);
3546 	*migrated = !r;
3547 
3548 	return 0;
3549 }
3550 
3551 int svm_range_schedule_evict_svm_bo(struct amdgpu_amdkfd_fence *fence)
3552 {
3553 	/* Dereferencing fence->svm_bo is safe here because the fence hasn't
3554 	 * signaled yet and we're under the protection of the fence->lock.
3555 	 * After the fence is signaled in svm_range_bo_release, we cannot get
3556 	 * here any more.
3557 	 *
3558 	 * Reference is dropped in svm_range_evict_svm_bo_worker.
3559 	 */
3560 	if (svm_bo_ref_unless_zero(fence->svm_bo)) {
3561 		WRITE_ONCE(fence->svm_bo->evicting, 1);
3562 		schedule_work(&fence->svm_bo->eviction_work);
3563 	}
3564 
3565 	return 0;
3566 }
3567 
3568 static void svm_range_evict_svm_bo_worker(struct work_struct *work)
3569 {
3570 	struct svm_range_bo *svm_bo;
3571 	struct mm_struct *mm;
3572 	int r = 0;
3573 
3574 	svm_bo = container_of(work, struct svm_range_bo, eviction_work);
3575 
3576 	if (mmget_not_zero(svm_bo->eviction_fence->mm)) {
3577 		mm = svm_bo->eviction_fence->mm;
3578 	} else {
3579 		svm_range_bo_unref(svm_bo);
3580 		return;
3581 	}
3582 
3583 	mmap_read_lock(mm);
3584 	spin_lock(&svm_bo->list_lock);
3585 	while (!list_empty(&svm_bo->range_list) && !r) {
3586 		struct svm_range *prange =
3587 				list_first_entry(&svm_bo->range_list,
3588 						struct svm_range, svm_bo_list);
3589 		int retries = 3;
3590 
3591 		list_del_init(&prange->svm_bo_list);
3592 		spin_unlock(&svm_bo->list_lock);
3593 
3594 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
3595 			 prange->start, prange->last);
3596 
3597 		mutex_lock(&prange->migrate_mutex);
3598 		do {
3599 			/* migrate all vram pages in this prange to sys ram
3600 			 * after that prange->actual_loc should be zero
3601 			 */
3602 			r = svm_migrate_vram_to_ram(prange, mm,
3603 					prange->start, prange->last,
3604 					KFD_MIGRATE_TRIGGER_TTM_EVICTION, NULL);
3605 		} while (!r && prange->actual_loc && --retries);
3606 
3607 		if (!r && prange->actual_loc)
3608 			pr_info_once("Migration failed during eviction");
3609 
3610 		if (!prange->actual_loc) {
3611 			mutex_lock(&prange->lock);
3612 			prange->svm_bo = NULL;
3613 			mutex_unlock(&prange->lock);
3614 		}
3615 		mutex_unlock(&prange->migrate_mutex);
3616 
3617 		spin_lock(&svm_bo->list_lock);
3618 	}
3619 	spin_unlock(&svm_bo->list_lock);
3620 	mmap_read_unlock(mm);
3621 	mmput(mm);
3622 
3623 	dma_fence_signal(&svm_bo->eviction_fence->base);
3624 
3625 	/* This is the last reference to svm_bo, after svm_range_vram_node_free
3626 	 * has been called in svm_migrate_vram_to_ram
3627 	 */
3628 	WARN_ONCE(!r && kref_read(&svm_bo->kref) != 1, "This was not the last reference\n");
3629 	svm_range_bo_unref(svm_bo);
3630 }
3631 
3632 static int
3633 svm_range_set_attr(struct kfd_process *p, struct mm_struct *mm,
3634 		   uint64_t start, uint64_t size, uint32_t nattr,
3635 		   struct kfd_ioctl_svm_attribute *attrs)
3636 {
3637 	struct amdkfd_process_info *process_info = p->kgd_process_info;
3638 	struct list_head update_list;
3639 	struct list_head insert_list;
3640 	struct list_head remove_list;
3641 	struct list_head remap_list;
3642 	struct svm_range_list *svms;
3643 	struct svm_range *prange;
3644 	struct svm_range *next;
3645 	bool update_mapping = false;
3646 	bool flush_tlb;
3647 	int r, ret = 0;
3648 
3649 	pr_debug("process pid %d svms 0x%p [0x%llx 0x%llx] pages 0x%llx\n",
3650 		 p->lead_thread->pid, &p->svms, start, start + size - 1, size);
3651 
3652 	r = svm_range_check_attr(p, nattr, attrs);
3653 	if (r)
3654 		return r;
3655 
3656 	svms = &p->svms;
3657 
3658 	mutex_lock(&process_info->lock);
3659 
3660 	svm_range_list_lock_and_flush_work(svms, mm);
3661 
3662 	r = svm_range_is_valid(p, start, size);
3663 	if (r) {
3664 		pr_debug("invalid range r=%d\n", r);
3665 		mmap_write_unlock(mm);
3666 		goto out;
3667 	}
3668 
3669 	mutex_lock(&svms->lock);
3670 
3671 	/* Add new range and split existing ranges as needed */
3672 	r = svm_range_add(p, start, size, nattr, attrs, &update_list,
3673 			  &insert_list, &remove_list, &remap_list);
3674 	if (r) {
3675 		mutex_unlock(&svms->lock);
3676 		mmap_write_unlock(mm);
3677 		goto out;
3678 	}
3679 	/* Apply changes as a transaction */
3680 	list_for_each_entry_safe(prange, next, &insert_list, list) {
3681 		svm_range_add_to_svms(prange);
3682 		svm_range_add_notifier_locked(mm, prange);
3683 	}
3684 	list_for_each_entry(prange, &update_list, update_list) {
3685 		svm_range_apply_attrs(p, prange, nattr, attrs, &update_mapping);
3686 		/* TODO: unmap ranges from GPU that lost access */
3687 	}
3688 	list_for_each_entry_safe(prange, next, &remove_list, update_list) {
3689 		pr_debug("unlink old 0x%p prange 0x%p [0x%lx 0x%lx]\n",
3690 			 prange->svms, prange, prange->start,
3691 			 prange->last);
3692 		svm_range_unlink(prange);
3693 		svm_range_remove_notifier(prange);
3694 		svm_range_free(prange, false);
3695 	}
3696 
3697 	mmap_write_downgrade(mm);
3698 	/* Trigger migrations and revalidate and map to GPUs as needed. If
3699 	 * this fails we may be left with partially completed actions. There
3700 	 * is no clean way of rolling back to the previous state in such a
3701 	 * case because the rollback wouldn't be guaranteed to work either.
3702 	 */
3703 	list_for_each_entry(prange, &update_list, update_list) {
3704 		bool migrated;
3705 
3706 		mutex_lock(&prange->migrate_mutex);
3707 
3708 		r = svm_range_trigger_migration(mm, prange, &migrated);
3709 		if (r)
3710 			goto out_unlock_range;
3711 
3712 		if (migrated && (!p->xnack_enabled ||
3713 		    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) &&
3714 		    prange->mapped_to_gpu) {
3715 			pr_debug("restore_work will update mappings of GPUs\n");
3716 			mutex_unlock(&prange->migrate_mutex);
3717 			continue;
3718 		}
3719 
3720 		if (!migrated && !update_mapping) {
3721 			mutex_unlock(&prange->migrate_mutex);
3722 			continue;
3723 		}
3724 
3725 		flush_tlb = !migrated && update_mapping && prange->mapped_to_gpu;
3726 
3727 		r = svm_range_validate_and_map(mm, prange->start, prange->last, prange,
3728 					       MAX_GPU_INSTANCE, true, true, flush_tlb);
3729 		if (r)
3730 			pr_debug("failed %d to map svm range\n", r);
3731 
3732 out_unlock_range:
3733 		mutex_unlock(&prange->migrate_mutex);
3734 		if (r)
3735 			ret = r;
3736 	}
3737 
3738 	list_for_each_entry(prange, &remap_list, update_list) {
3739 		pr_debug("Remapping prange 0x%p [0x%lx 0x%lx]\n",
3740 			 prange, prange->start, prange->last);
3741 		mutex_lock(&prange->migrate_mutex);
3742 		r = svm_range_validate_and_map(mm,  prange->start, prange->last, prange,
3743 					       MAX_GPU_INSTANCE, true, true, prange->mapped_to_gpu);
3744 		if (r)
3745 			pr_debug("failed %d on remap svm range\n", r);
3746 		mutex_unlock(&prange->migrate_mutex);
3747 		if (r)
3748 			ret = r;
3749 	}
3750 
3751 	dynamic_svm_range_dump(svms);
3752 
3753 	mutex_unlock(&svms->lock);
3754 	mmap_read_unlock(mm);
3755 out:
3756 	mutex_unlock(&process_info->lock);
3757 
3758 	pr_debug("process pid %d svms 0x%p [0x%llx 0x%llx] done, r=%d\n",
3759 		 p->lead_thread->pid, &p->svms, start, start + size - 1, r);
3760 
3761 	return ret ? ret : r;
3762 }
3763 
3764 static int
3765 svm_range_get_attr(struct kfd_process *p, struct mm_struct *mm,
3766 		   uint64_t start, uint64_t size, uint32_t nattr,
3767 		   struct kfd_ioctl_svm_attribute *attrs)
3768 {
3769 	DECLARE_BITMAP(bitmap_access, MAX_GPU_INSTANCE);
3770 	DECLARE_BITMAP(bitmap_aip, MAX_GPU_INSTANCE);
3771 	bool get_preferred_loc = false;
3772 	bool get_prefetch_loc = false;
3773 	bool get_granularity = false;
3774 	bool get_accessible = false;
3775 	bool get_flags = false;
3776 	uint64_t last = start + size - 1UL;
3777 	uint8_t granularity = 0xff;
3778 	struct interval_tree_node *node;
3779 	struct svm_range_list *svms;
3780 	struct svm_range *prange;
3781 	uint32_t prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3782 	uint32_t location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3783 	uint32_t flags_and = 0xffffffff;
3784 	uint32_t flags_or = 0;
3785 	int gpuidx;
3786 	uint32_t i;
3787 	int r = 0;
3788 
3789 	pr_debug("svms 0x%p [0x%llx 0x%llx] nattr 0x%x\n", &p->svms, start,
3790 		 start + size - 1, nattr);
3791 
3792 	/* Flush pending deferred work to avoid racing with deferred actions from
3793 	 * previous memory map changes (e.g. munmap). Concurrent memory map changes
3794 	 * can still race with get_attr because we don't hold the mmap lock. But that
3795 	 * would be a race condition in the application anyway, and undefined
3796 	 * behaviour is acceptable in that case.
3797 	 */
3798 	flush_work(&p->svms.deferred_list_work);
3799 
3800 	mmap_read_lock(mm);
3801 	r = svm_range_is_valid(p, start, size);
3802 	mmap_read_unlock(mm);
3803 	if (r) {
3804 		pr_debug("invalid range r=%d\n", r);
3805 		return r;
3806 	}
3807 
3808 	for (i = 0; i < nattr; i++) {
3809 		switch (attrs[i].type) {
3810 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3811 			get_preferred_loc = true;
3812 			break;
3813 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3814 			get_prefetch_loc = true;
3815 			break;
3816 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3817 			get_accessible = true;
3818 			break;
3819 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3820 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3821 			get_flags = true;
3822 			break;
3823 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3824 			get_granularity = true;
3825 			break;
3826 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
3827 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
3828 			fallthrough;
3829 		default:
3830 			pr_debug("get invalid attr type 0x%x\n", attrs[i].type);
3831 			return -EINVAL;
3832 		}
3833 	}
3834 
3835 	svms = &p->svms;
3836 
3837 	mutex_lock(&svms->lock);
3838 
3839 	node = interval_tree_iter_first(&svms->objects, start, last);
3840 	if (!node) {
3841 		pr_debug("range attrs not found return default values\n");
3842 		svm_range_set_default_attributes(svms, &location, &prefetch_loc,
3843 						 &granularity, &flags_and);
3844 		flags_or = flags_and;
3845 		if (p->xnack_enabled)
3846 			bitmap_copy(bitmap_access, svms->bitmap_supported,
3847 				    MAX_GPU_INSTANCE);
3848 		else
3849 			bitmap_zero(bitmap_access, MAX_GPU_INSTANCE);
3850 		bitmap_zero(bitmap_aip, MAX_GPU_INSTANCE);
3851 		goto fill_values;
3852 	}
3853 	bitmap_copy(bitmap_access, svms->bitmap_supported, MAX_GPU_INSTANCE);
3854 	bitmap_copy(bitmap_aip, svms->bitmap_supported, MAX_GPU_INSTANCE);
3855 
3856 	while (node) {
3857 		struct interval_tree_node *next;
3858 
3859 		prange = container_of(node, struct svm_range, it_node);
3860 		next = interval_tree_iter_next(node, start, last);
3861 
3862 		if (get_preferred_loc) {
3863 			if (prange->preferred_loc ==
3864 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3865 			    (location != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3866 			     location != prange->preferred_loc)) {
3867 				location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3868 				get_preferred_loc = false;
3869 			} else {
3870 				location = prange->preferred_loc;
3871 			}
3872 		}
3873 		if (get_prefetch_loc) {
3874 			if (prange->prefetch_loc ==
3875 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3876 			    (prefetch_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3877 			     prefetch_loc != prange->prefetch_loc)) {
3878 				prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3879 				get_prefetch_loc = false;
3880 			} else {
3881 				prefetch_loc = prange->prefetch_loc;
3882 			}
3883 		}
3884 		if (get_accessible) {
3885 			bitmap_and(bitmap_access, bitmap_access,
3886 				   prange->bitmap_access, MAX_GPU_INSTANCE);
3887 			bitmap_and(bitmap_aip, bitmap_aip,
3888 				   prange->bitmap_aip, MAX_GPU_INSTANCE);
3889 		}
3890 		if (get_flags) {
3891 			flags_and &= prange->flags;
3892 			flags_or |= prange->flags;
3893 		}
3894 
3895 		if (get_granularity && prange->granularity < granularity)
3896 			granularity = prange->granularity;
3897 
3898 		node = next;
3899 	}
3900 fill_values:
3901 	mutex_unlock(&svms->lock);
3902 
3903 	for (i = 0; i < nattr; i++) {
3904 		switch (attrs[i].type) {
3905 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3906 			attrs[i].value = location;
3907 			break;
3908 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3909 			attrs[i].value = prefetch_loc;
3910 			break;
3911 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3912 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
3913 							       attrs[i].value);
3914 			if (gpuidx < 0) {
3915 				pr_debug("invalid gpuid %x\n", attrs[i].value);
3916 				return -EINVAL;
3917 			}
3918 			if (test_bit(gpuidx, bitmap_access))
3919 				attrs[i].type = KFD_IOCTL_SVM_ATTR_ACCESS;
3920 			else if (test_bit(gpuidx, bitmap_aip))
3921 				attrs[i].type =
3922 					KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE;
3923 			else
3924 				attrs[i].type = KFD_IOCTL_SVM_ATTR_NO_ACCESS;
3925 			break;
3926 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3927 			attrs[i].value = flags_and;
3928 			break;
3929 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3930 			attrs[i].value = ~flags_or;
3931 			break;
3932 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3933 			attrs[i].value = (uint32_t)granularity;
3934 			break;
3935 		}
3936 	}
3937 
3938 	return 0;
3939 }
3940 
3941 int kfd_criu_resume_svm(struct kfd_process *p)
3942 {
3943 	struct kfd_ioctl_svm_attribute *set_attr_new, *set_attr = NULL;
3944 	int nattr_common = 4, nattr_accessibility = 1;
3945 	struct criu_svm_metadata *criu_svm_md = NULL;
3946 	struct svm_range_list *svms = &p->svms;
3947 	struct criu_svm_metadata *next = NULL;
3948 	uint32_t set_flags = 0xffffffff;
3949 	int i, j, num_attrs, ret = 0;
3950 	uint64_t set_attr_size;
3951 	struct mm_struct *mm;
3952 
3953 	if (list_empty(&svms->criu_svm_metadata_list)) {
3954 		pr_debug("No SVM data from CRIU restore stage 2\n");
3955 		return ret;
3956 	}
3957 
3958 	mm = get_task_mm(p->lead_thread);
3959 	if (!mm) {
3960 		pr_err("failed to get mm for the target process\n");
3961 		return -ESRCH;
3962 	}
3963 
3964 	num_attrs = nattr_common + (nattr_accessibility * p->n_pdds);
3965 
3966 	i = j = 0;
3967 	list_for_each_entry(criu_svm_md, &svms->criu_svm_metadata_list, list) {
3968 		pr_debug("criu_svm_md[%d]\n\tstart: 0x%llx size: 0x%llx (npages)\n",
3969 			 i, criu_svm_md->data.start_addr, criu_svm_md->data.size);
3970 
3971 		for (j = 0; j < num_attrs; j++) {
3972 			pr_debug("\ncriu_svm_md[%d]->attrs[%d].type : 0x%x\ncriu_svm_md[%d]->attrs[%d].value : 0x%x\n",
3973 				 i, j, criu_svm_md->data.attrs[j].type,
3974 				 i, j, criu_svm_md->data.attrs[j].value);
3975 			switch (criu_svm_md->data.attrs[j].type) {
3976 			/* During Checkpoint operation, the query for
3977 			 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC attribute might
3978 			 * return KFD_IOCTL_SVM_LOCATION_UNDEFINED if they were
3979 			 * not used by the range which was checkpointed. Care
3980 			 * must be taken to not restore with an invalid value
3981 			 * otherwise the gpuidx value will be invalid and
3982 			 * set_attr would eventually fail so just replace those
3983 			 * with another dummy attribute such as
3984 			 * KFD_IOCTL_SVM_ATTR_SET_FLAGS.
3985 			 */
3986 			case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3987 				if (criu_svm_md->data.attrs[j].value ==
3988 				    KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
3989 					criu_svm_md->data.attrs[j].type =
3990 						KFD_IOCTL_SVM_ATTR_SET_FLAGS;
3991 					criu_svm_md->data.attrs[j].value = 0;
3992 				}
3993 				break;
3994 			case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3995 				set_flags = criu_svm_md->data.attrs[j].value;
3996 				break;
3997 			default:
3998 				break;
3999 			}
4000 		}
4001 
4002 		/* CLR_FLAGS is not available via get_attr during checkpoint but
4003 		 * it needs to be inserted before restoring the ranges so
4004 		 * allocate extra space for it before calling set_attr
4005 		 */
4006 		set_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4007 						(num_attrs + 1);
4008 		set_attr_new = krealloc(set_attr, set_attr_size,
4009 					    GFP_KERNEL);
4010 		if (!set_attr_new) {
4011 			ret = -ENOMEM;
4012 			goto exit;
4013 		}
4014 		set_attr = set_attr_new;
4015 
4016 		memcpy(set_attr, criu_svm_md->data.attrs, num_attrs *
4017 					sizeof(struct kfd_ioctl_svm_attribute));
4018 		set_attr[num_attrs].type = KFD_IOCTL_SVM_ATTR_CLR_FLAGS;
4019 		set_attr[num_attrs].value = ~set_flags;
4020 
4021 		ret = svm_range_set_attr(p, mm, criu_svm_md->data.start_addr,
4022 					 criu_svm_md->data.size, num_attrs + 1,
4023 					 set_attr);
4024 		if (ret) {
4025 			pr_err("CRIU: failed to set range attributes\n");
4026 			goto exit;
4027 		}
4028 
4029 		i++;
4030 	}
4031 exit:
4032 	kfree(set_attr);
4033 	list_for_each_entry_safe(criu_svm_md, next, &svms->criu_svm_metadata_list, list) {
4034 		pr_debug("freeing criu_svm_md[]\n\tstart: 0x%llx\n",
4035 						criu_svm_md->data.start_addr);
4036 		kfree(criu_svm_md);
4037 	}
4038 
4039 	mmput(mm);
4040 	return ret;
4041 
4042 }
4043 
4044 int kfd_criu_restore_svm(struct kfd_process *p,
4045 			 uint8_t __user *user_priv_ptr,
4046 			 uint64_t *priv_data_offset,
4047 			 uint64_t max_priv_data_size)
4048 {
4049 	uint64_t svm_priv_data_size, svm_object_md_size, svm_attrs_size;
4050 	int nattr_common = 4, nattr_accessibility = 1;
4051 	struct criu_svm_metadata *criu_svm_md = NULL;
4052 	struct svm_range_list *svms = &p->svms;
4053 	uint32_t num_devices;
4054 	int ret = 0;
4055 
4056 	num_devices = p->n_pdds;
4057 	/* Handle one SVM range object at a time, also the number of gpus are
4058 	 * assumed to be same on the restore node, checking must be done while
4059 	 * evaluating the topology earlier
4060 	 */
4061 
4062 	svm_attrs_size = sizeof(struct kfd_ioctl_svm_attribute) *
4063 		(nattr_common + nattr_accessibility * num_devices);
4064 	svm_object_md_size = sizeof(struct criu_svm_metadata) + svm_attrs_size;
4065 
4066 	svm_priv_data_size = sizeof(struct kfd_criu_svm_range_priv_data) +
4067 								svm_attrs_size;
4068 
4069 	criu_svm_md = kzalloc(svm_object_md_size, GFP_KERNEL);
4070 	if (!criu_svm_md) {
4071 		pr_err("failed to allocate memory to store svm metadata\n");
4072 		return -ENOMEM;
4073 	}
4074 	if (*priv_data_offset + svm_priv_data_size > max_priv_data_size) {
4075 		ret = -EINVAL;
4076 		goto exit;
4077 	}
4078 
4079 	ret = copy_from_user(&criu_svm_md->data, user_priv_ptr + *priv_data_offset,
4080 			     svm_priv_data_size);
4081 	if (ret) {
4082 		ret = -EFAULT;
4083 		goto exit;
4084 	}
4085 	*priv_data_offset += svm_priv_data_size;
4086 
4087 	list_add_tail(&criu_svm_md->list, &svms->criu_svm_metadata_list);
4088 
4089 	return 0;
4090 
4091 
4092 exit:
4093 	kfree(criu_svm_md);
4094 	return ret;
4095 }
4096 
4097 void svm_range_get_info(struct kfd_process *p, uint32_t *num_svm_ranges,
4098 			uint64_t *svm_priv_data_size)
4099 {
4100 	uint64_t total_size, accessibility_size, common_attr_size;
4101 	int nattr_common = 4, nattr_accessibility = 1;
4102 	int num_devices = p->n_pdds;
4103 	struct svm_range_list *svms;
4104 	struct svm_range *prange;
4105 	uint32_t count = 0;
4106 
4107 	*svm_priv_data_size = 0;
4108 
4109 	svms = &p->svms;
4110 
4111 	mutex_lock(&svms->lock);
4112 	list_for_each_entry(prange, &svms->list, list) {
4113 		pr_debug("prange: 0x%p start: 0x%lx\t npages: 0x%llx\t end: 0x%llx\n",
4114 			 prange, prange->start, prange->npages,
4115 			 prange->start + prange->npages - 1);
4116 		count++;
4117 	}
4118 	mutex_unlock(&svms->lock);
4119 
4120 	*num_svm_ranges = count;
4121 	/* Only the accessbility attributes need to be queried for all the gpus
4122 	 * individually, remaining ones are spanned across the entire process
4123 	 * regardless of the various gpu nodes. Of the remaining attributes,
4124 	 * KFD_IOCTL_SVM_ATTR_CLR_FLAGS need not be saved.
4125 	 *
4126 	 * KFD_IOCTL_SVM_ATTR_PREFERRED_LOC
4127 	 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC
4128 	 * KFD_IOCTL_SVM_ATTR_SET_FLAGS
4129 	 * KFD_IOCTL_SVM_ATTR_GRANULARITY
4130 	 *
4131 	 * ** ACCESSBILITY ATTRIBUTES **
4132 	 * (Considered as one, type is altered during query, value is gpuid)
4133 	 * KFD_IOCTL_SVM_ATTR_ACCESS
4134 	 * KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE
4135 	 * KFD_IOCTL_SVM_ATTR_NO_ACCESS
4136 	 */
4137 	if (*num_svm_ranges > 0) {
4138 		common_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4139 			nattr_common;
4140 		accessibility_size = sizeof(struct kfd_ioctl_svm_attribute) *
4141 			nattr_accessibility * num_devices;
4142 
4143 		total_size = sizeof(struct kfd_criu_svm_range_priv_data) +
4144 			common_attr_size + accessibility_size;
4145 
4146 		*svm_priv_data_size = *num_svm_ranges * total_size;
4147 	}
4148 
4149 	pr_debug("num_svm_ranges %u total_priv_size %llu\n", *num_svm_ranges,
4150 		 *svm_priv_data_size);
4151 }
4152 
4153 int kfd_criu_checkpoint_svm(struct kfd_process *p,
4154 			    uint8_t __user *user_priv_data,
4155 			    uint64_t *priv_data_offset)
4156 {
4157 	struct kfd_criu_svm_range_priv_data *svm_priv = NULL;
4158 	struct kfd_ioctl_svm_attribute *query_attr = NULL;
4159 	uint64_t svm_priv_data_size, query_attr_size = 0;
4160 	int index, nattr_common = 4, ret = 0;
4161 	struct svm_range_list *svms;
4162 	int num_devices = p->n_pdds;
4163 	struct svm_range *prange;
4164 	struct mm_struct *mm;
4165 
4166 	svms = &p->svms;
4167 
4168 	mm = get_task_mm(p->lead_thread);
4169 	if (!mm) {
4170 		pr_err("failed to get mm for the target process\n");
4171 		return -ESRCH;
4172 	}
4173 
4174 	query_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4175 				(nattr_common + num_devices);
4176 
4177 	query_attr = kzalloc(query_attr_size, GFP_KERNEL);
4178 	if (!query_attr) {
4179 		ret = -ENOMEM;
4180 		goto exit;
4181 	}
4182 
4183 	query_attr[0].type = KFD_IOCTL_SVM_ATTR_PREFERRED_LOC;
4184 	query_attr[1].type = KFD_IOCTL_SVM_ATTR_PREFETCH_LOC;
4185 	query_attr[2].type = KFD_IOCTL_SVM_ATTR_SET_FLAGS;
4186 	query_attr[3].type = KFD_IOCTL_SVM_ATTR_GRANULARITY;
4187 
4188 	for (index = 0; index < num_devices; index++) {
4189 		struct kfd_process_device *pdd = p->pdds[index];
4190 
4191 		query_attr[index + nattr_common].type =
4192 			KFD_IOCTL_SVM_ATTR_ACCESS;
4193 		query_attr[index + nattr_common].value = pdd->user_gpu_id;
4194 	}
4195 
4196 	svm_priv_data_size = sizeof(*svm_priv) + query_attr_size;
4197 
4198 	svm_priv = kzalloc(svm_priv_data_size, GFP_KERNEL);
4199 	if (!svm_priv) {
4200 		ret = -ENOMEM;
4201 		goto exit_query;
4202 	}
4203 
4204 	index = 0;
4205 	list_for_each_entry(prange, &svms->list, list) {
4206 
4207 		svm_priv->object_type = KFD_CRIU_OBJECT_TYPE_SVM_RANGE;
4208 		svm_priv->start_addr = prange->start;
4209 		svm_priv->size = prange->npages;
4210 		memcpy(&svm_priv->attrs, query_attr, query_attr_size);
4211 		pr_debug("CRIU: prange: 0x%p start: 0x%lx\t npages: 0x%llx end: 0x%llx\t size: 0x%llx\n",
4212 			 prange, prange->start, prange->npages,
4213 			 prange->start + prange->npages - 1,
4214 			 prange->npages * PAGE_SIZE);
4215 
4216 		ret = svm_range_get_attr(p, mm, svm_priv->start_addr,
4217 					 svm_priv->size,
4218 					 (nattr_common + num_devices),
4219 					 svm_priv->attrs);
4220 		if (ret) {
4221 			pr_err("CRIU: failed to obtain range attributes\n");
4222 			goto exit_priv;
4223 		}
4224 
4225 		if (copy_to_user(user_priv_data + *priv_data_offset, svm_priv,
4226 				 svm_priv_data_size)) {
4227 			pr_err("Failed to copy svm priv to user\n");
4228 			ret = -EFAULT;
4229 			goto exit_priv;
4230 		}
4231 
4232 		*priv_data_offset += svm_priv_data_size;
4233 
4234 	}
4235 
4236 
4237 exit_priv:
4238 	kfree(svm_priv);
4239 exit_query:
4240 	kfree(query_attr);
4241 exit:
4242 	mmput(mm);
4243 	return ret;
4244 }
4245 
4246 int
4247 svm_ioctl(struct kfd_process *p, enum kfd_ioctl_svm_op op, uint64_t start,
4248 	  uint64_t size, uint32_t nattrs, struct kfd_ioctl_svm_attribute *attrs)
4249 {
4250 	struct mm_struct *mm = current->mm;
4251 	int r;
4252 
4253 	start >>= PAGE_SHIFT;
4254 	size >>= PAGE_SHIFT;
4255 
4256 	switch (op) {
4257 	case KFD_IOCTL_SVM_OP_SET_ATTR:
4258 		r = svm_range_set_attr(p, mm, start, size, nattrs, attrs);
4259 		break;
4260 	case KFD_IOCTL_SVM_OP_GET_ATTR:
4261 		r = svm_range_get_attr(p, mm, start, size, nattrs, attrs);
4262 		break;
4263 	default:
4264 		r = -EINVAL;
4265 		break;
4266 	}
4267 
4268 	return r;
4269 }
4270