xref: /linux/drivers/gpu/drm/amd/amdkfd/kfd_svm.c (revision 4492d54d59872bb72e119ff9f77969ab4d8a0e6b)
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 amdgpu_hmm_range *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 			range = amdgpu_hmm_range_alloc(NULL);
1741 			if (likely(range))
1742 				r = amdgpu_hmm_range_get_pages(&prange->notifier, addr, npages,
1743 							       readonly, owner, range);
1744 			else
1745 				r = -ENOMEM;
1746 			WRITE_ONCE(p->svms.faulting_task, NULL);
1747 			if (r) {
1748 				amdgpu_hmm_range_free(range);
1749 				range = NULL;
1750 				pr_debug("failed %d to get svm range pages\n", r);
1751 			}
1752 		} else {
1753 			r = -EFAULT;
1754 		}
1755 
1756 		if (!r) {
1757 			offset = (addr >> PAGE_SHIFT) - prange->start;
1758 			r = svm_range_dma_map(prange, ctx->bitmap, offset, npages,
1759 					      range->hmm_range.hmm_pfns);
1760 			if (r)
1761 				pr_debug("failed %d to dma map range\n", r);
1762 		}
1763 
1764 		svm_range_lock(prange);
1765 
1766 		/* Free backing memory of hmm_range if it was initialized
1767 		 * Override return value to TRY AGAIN only if prior returns
1768 		 * were successful
1769 		 */
1770 		if (range && !amdgpu_hmm_range_valid(range) && !r) {
1771 			pr_debug("hmm update the range, need validate again\n");
1772 			r = -EAGAIN;
1773 		}
1774 		/* Free the hmm range */
1775 		if (range)
1776 			amdgpu_hmm_range_free(range);
1777 
1778 
1779 		if (!r && !list_empty(&prange->child_list)) {
1780 			pr_debug("range split by unmap in parallel, validate again\n");
1781 			r = -EAGAIN;
1782 		}
1783 
1784 		if (!r) {
1785 			map_start_vma = max(map_start, prange->start + offset);
1786 			map_last_vma = min(map_last, prange->start + offset + npages - 1);
1787 			if (map_start_vma <= map_last_vma) {
1788 				offset = map_start_vma - prange->start;
1789 				npages = map_last_vma - map_start_vma + 1;
1790 				r = svm_range_map_to_gpus(prange, offset, npages, readonly,
1791 							  ctx->bitmap, wait, flush_tlb);
1792 			}
1793 		}
1794 
1795 		if (!r && next == end)
1796 			prange->mapped_to_gpu = true;
1797 
1798 		svm_range_unlock(prange);
1799 
1800 		addr = next;
1801 	}
1802 
1803 	svm_range_unreserve_bos(ctx);
1804 	if (!r)
1805 		prange->validate_timestamp = ktime_get_boottime();
1806 
1807 free_ctx:
1808 	kfree(ctx);
1809 
1810 	return r;
1811 }
1812 
1813 /**
1814  * svm_range_list_lock_and_flush_work - flush pending deferred work
1815  *
1816  * @svms: the svm range list
1817  * @mm: the mm structure
1818  *
1819  * Context: Returns with mmap write lock held, pending deferred work flushed
1820  *
1821  */
1822 void
1823 svm_range_list_lock_and_flush_work(struct svm_range_list *svms,
1824 				   struct mm_struct *mm)
1825 {
1826 retry_flush_work:
1827 	flush_work(&svms->deferred_list_work);
1828 	mmap_write_lock(mm);
1829 
1830 	if (list_empty(&svms->deferred_range_list))
1831 		return;
1832 	mmap_write_unlock(mm);
1833 	pr_debug("retry flush\n");
1834 	goto retry_flush_work;
1835 }
1836 
1837 static void svm_range_restore_work(struct work_struct *work)
1838 {
1839 	struct delayed_work *dwork = to_delayed_work(work);
1840 	struct amdkfd_process_info *process_info;
1841 	struct svm_range_list *svms;
1842 	struct svm_range *prange;
1843 	struct kfd_process *p;
1844 	struct mm_struct *mm;
1845 	int evicted_ranges;
1846 	int invalid;
1847 	int r;
1848 
1849 	svms = container_of(dwork, struct svm_range_list, restore_work);
1850 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1851 	if (!evicted_ranges)
1852 		return;
1853 
1854 	pr_debug("restore svm ranges\n");
1855 
1856 	p = container_of(svms, struct kfd_process, svms);
1857 	process_info = p->kgd_process_info;
1858 
1859 	/* Keep mm reference when svm_range_validate_and_map ranges */
1860 	mm = get_task_mm(p->lead_thread);
1861 	if (!mm) {
1862 		pr_debug("svms 0x%p process mm gone\n", svms);
1863 		return;
1864 	}
1865 
1866 	mutex_lock(&process_info->lock);
1867 	svm_range_list_lock_and_flush_work(svms, mm);
1868 	mutex_lock(&svms->lock);
1869 
1870 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1871 
1872 	list_for_each_entry(prange, &svms->list, list) {
1873 		invalid = atomic_read(&prange->invalid);
1874 		if (!invalid)
1875 			continue;
1876 
1877 		pr_debug("restoring svms 0x%p prange 0x%p [0x%lx %lx] inv %d\n",
1878 			 prange->svms, prange, prange->start, prange->last,
1879 			 invalid);
1880 
1881 		/*
1882 		 * If range is migrating, wait for migration is done.
1883 		 */
1884 		mutex_lock(&prange->migrate_mutex);
1885 
1886 		r = svm_range_validate_and_map(mm, prange->start, prange->last, prange,
1887 					       MAX_GPU_INSTANCE, false, true, false);
1888 		if (r)
1889 			pr_debug("failed %d to map 0x%lx to gpus\n", r,
1890 				 prange->start);
1891 
1892 		mutex_unlock(&prange->migrate_mutex);
1893 		if (r)
1894 			goto out_reschedule;
1895 
1896 		if (atomic_cmpxchg(&prange->invalid, invalid, 0) != invalid)
1897 			goto out_reschedule;
1898 	}
1899 
1900 	if (atomic_cmpxchg(&svms->evicted_ranges, evicted_ranges, 0) !=
1901 	    evicted_ranges)
1902 		goto out_reschedule;
1903 
1904 	evicted_ranges = 0;
1905 
1906 	r = kgd2kfd_resume_mm(mm);
1907 	if (r) {
1908 		/* No recovery from this failure. Probably the CP is
1909 		 * hanging. No point trying again.
1910 		 */
1911 		pr_debug("failed %d to resume KFD\n", r);
1912 	}
1913 
1914 	pr_debug("restore svm ranges successfully\n");
1915 
1916 out_reschedule:
1917 	mutex_unlock(&svms->lock);
1918 	mmap_write_unlock(mm);
1919 	mutex_unlock(&process_info->lock);
1920 
1921 	/* If validation failed, reschedule another attempt */
1922 	if (evicted_ranges) {
1923 		pr_debug("reschedule to restore svm range\n");
1924 		queue_delayed_work(system_freezable_wq, &svms->restore_work,
1925 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1926 
1927 		kfd_smi_event_queue_restore_rescheduled(mm);
1928 	}
1929 	mmput(mm);
1930 }
1931 
1932 /**
1933  * svm_range_evict - evict svm range
1934  * @prange: svm range structure
1935  * @mm: current process mm_struct
1936  * @start: starting process queue number
1937  * @last: last process queue number
1938  * @event: mmu notifier event when range is evicted or migrated
1939  *
1940  * Stop all queues of the process to ensure GPU doesn't access the memory, then
1941  * return to let CPU evict the buffer and proceed CPU pagetable update.
1942  *
1943  * Don't need use lock to sync cpu pagetable invalidation with GPU execution.
1944  * If invalidation happens while restore work is running, restore work will
1945  * restart to ensure to get the latest CPU pages mapping to GPU, then start
1946  * the queues.
1947  */
1948 static int
1949 svm_range_evict(struct svm_range *prange, struct mm_struct *mm,
1950 		unsigned long start, unsigned long last,
1951 		enum mmu_notifier_event event)
1952 {
1953 	struct svm_range_list *svms = prange->svms;
1954 	struct svm_range *pchild;
1955 	struct kfd_process *p;
1956 	int r = 0;
1957 
1958 	p = container_of(svms, struct kfd_process, svms);
1959 
1960 	pr_debug("invalidate svms 0x%p prange [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
1961 		 svms, prange->start, prange->last, start, last);
1962 
1963 	if (!p->xnack_enabled ||
1964 	    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) {
1965 		int evicted_ranges;
1966 		bool mapped = prange->mapped_to_gpu;
1967 
1968 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1969 			if (!pchild->mapped_to_gpu)
1970 				continue;
1971 			mapped = true;
1972 			mutex_lock_nested(&pchild->lock, 1);
1973 			if (pchild->start <= last && pchild->last >= start) {
1974 				pr_debug("increment pchild invalid [0x%lx 0x%lx]\n",
1975 					 pchild->start, pchild->last);
1976 				atomic_inc(&pchild->invalid);
1977 			}
1978 			mutex_unlock(&pchild->lock);
1979 		}
1980 
1981 		if (!mapped)
1982 			return r;
1983 
1984 		if (prange->start <= last && prange->last >= start)
1985 			atomic_inc(&prange->invalid);
1986 
1987 		evicted_ranges = atomic_inc_return(&svms->evicted_ranges);
1988 		if (evicted_ranges != 1)
1989 			return r;
1990 
1991 		pr_debug("evicting svms 0x%p range [0x%lx 0x%lx]\n",
1992 			 prange->svms, prange->start, prange->last);
1993 
1994 		/* First eviction, stop the queues */
1995 		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_SVM);
1996 		if (r)
1997 			pr_debug("failed to quiesce KFD\n");
1998 
1999 		pr_debug("schedule to restore svm %p ranges\n", svms);
2000 		queue_delayed_work(system_freezable_wq, &svms->restore_work,
2001 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
2002 	} else {
2003 		unsigned long s, l;
2004 		uint32_t trigger;
2005 
2006 		if (event == MMU_NOTIFY_MIGRATE)
2007 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY_MIGRATE;
2008 		else
2009 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY;
2010 
2011 		pr_debug("invalidate unmap svms 0x%p [0x%lx 0x%lx] from GPUs\n",
2012 			 prange->svms, start, last);
2013 		list_for_each_entry(pchild, &prange->child_list, child_list) {
2014 			mutex_lock_nested(&pchild->lock, 1);
2015 			s = max(start, pchild->start);
2016 			l = min(last, pchild->last);
2017 			if (l >= s)
2018 				svm_range_unmap_from_gpus(pchild, s, l, trigger);
2019 			mutex_unlock(&pchild->lock);
2020 		}
2021 		s = max(start, prange->start);
2022 		l = min(last, prange->last);
2023 		if (l >= s)
2024 			svm_range_unmap_from_gpus(prange, s, l, trigger);
2025 	}
2026 
2027 	return r;
2028 }
2029 
2030 static struct svm_range *svm_range_clone(struct svm_range *old)
2031 {
2032 	struct svm_range *new;
2033 
2034 	new = svm_range_new(old->svms, old->start, old->last, false);
2035 	if (!new)
2036 		return NULL;
2037 	if (svm_range_copy_dma_addrs(new, old)) {
2038 		svm_range_free(new, false);
2039 		return NULL;
2040 	}
2041 	if (old->svm_bo) {
2042 		new->ttm_res = old->ttm_res;
2043 		new->offset = old->offset;
2044 		new->svm_bo = svm_range_bo_ref(old->svm_bo);
2045 		spin_lock(&new->svm_bo->list_lock);
2046 		list_add(&new->svm_bo_list, &new->svm_bo->range_list);
2047 		spin_unlock(&new->svm_bo->list_lock);
2048 	}
2049 	new->flags = old->flags;
2050 	new->preferred_loc = old->preferred_loc;
2051 	new->prefetch_loc = old->prefetch_loc;
2052 	new->actual_loc = old->actual_loc;
2053 	new->granularity = old->granularity;
2054 	new->mapped_to_gpu = old->mapped_to_gpu;
2055 	new->vram_pages = old->vram_pages;
2056 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
2057 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
2058 	atomic_set(&new->queue_refcount, atomic_read(&old->queue_refcount));
2059 
2060 	return new;
2061 }
2062 
2063 void svm_range_set_max_pages(struct amdgpu_device *adev)
2064 {
2065 	uint64_t max_pages;
2066 	uint64_t pages, _pages;
2067 	uint64_t min_pages = 0;
2068 	int i, id;
2069 
2070 	for (i = 0; i < adev->kfd.dev->num_nodes; i++) {
2071 		if (adev->kfd.dev->nodes[i]->xcp)
2072 			id = adev->kfd.dev->nodes[i]->xcp->id;
2073 		else
2074 			id = -1;
2075 		pages = KFD_XCP_MEMORY_SIZE(adev, id) >> 17;
2076 		pages = clamp(pages, 1ULL << 9, 1ULL << 18);
2077 		pages = rounddown_pow_of_two(pages);
2078 		min_pages = min_not_zero(min_pages, pages);
2079 	}
2080 
2081 	do {
2082 		max_pages = READ_ONCE(max_svm_range_pages);
2083 		_pages = min_not_zero(max_pages, min_pages);
2084 	} while (cmpxchg(&max_svm_range_pages, max_pages, _pages) != max_pages);
2085 }
2086 
2087 static int
2088 svm_range_split_new(struct svm_range_list *svms, uint64_t start, uint64_t last,
2089 		    uint64_t max_pages, struct list_head *insert_list,
2090 		    struct list_head *update_list)
2091 {
2092 	struct svm_range *prange;
2093 	uint64_t l;
2094 
2095 	pr_debug("max_svm_range_pages 0x%llx adding [0x%llx 0x%llx]\n",
2096 		 max_pages, start, last);
2097 
2098 	while (last >= start) {
2099 		l = min(last, ALIGN_DOWN(start + max_pages, max_pages) - 1);
2100 
2101 		prange = svm_range_new(svms, start, l, true);
2102 		if (!prange)
2103 			return -ENOMEM;
2104 		list_add(&prange->list, insert_list);
2105 		list_add(&prange->update_list, update_list);
2106 
2107 		start = l + 1;
2108 	}
2109 	return 0;
2110 }
2111 
2112 /**
2113  * svm_range_add - add svm range and handle overlap
2114  * @p: the range add to this process svms
2115  * @start: page size aligned
2116  * @size: page size aligned
2117  * @nattr: number of attributes
2118  * @attrs: array of attributes
2119  * @update_list: output, the ranges need validate and update GPU mapping
2120  * @insert_list: output, the ranges need insert to svms
2121  * @remove_list: output, the ranges are replaced and need remove from svms
2122  * @remap_list: output, remap unaligned svm ranges
2123  *
2124  * Check if the virtual address range has overlap with any existing ranges,
2125  * split partly overlapping ranges and add new ranges in the gaps. All changes
2126  * should be applied to the range_list and interval tree transactionally. If
2127  * any range split or allocation fails, the entire update fails. Therefore any
2128  * existing overlapping svm_ranges are cloned and the original svm_ranges left
2129  * unchanged.
2130  *
2131  * If the transaction succeeds, the caller can update and insert clones and
2132  * new ranges, then free the originals.
2133  *
2134  * Otherwise the caller can free the clones and new ranges, while the old
2135  * svm_ranges remain unchanged.
2136  *
2137  * Context: Process context, caller must hold svms->lock
2138  *
2139  * Return:
2140  * 0 - OK, otherwise error code
2141  */
2142 static int
2143 svm_range_add(struct kfd_process *p, uint64_t start, uint64_t size,
2144 	      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
2145 	      struct list_head *update_list, struct list_head *insert_list,
2146 	      struct list_head *remove_list, struct list_head *remap_list)
2147 {
2148 	unsigned long last = start + size - 1UL;
2149 	struct svm_range_list *svms = &p->svms;
2150 	struct interval_tree_node *node;
2151 	struct svm_range *prange;
2152 	struct svm_range *tmp;
2153 	struct list_head new_list;
2154 	int r = 0;
2155 
2156 	pr_debug("svms 0x%p [0x%llx 0x%lx]\n", &p->svms, start, last);
2157 
2158 	INIT_LIST_HEAD(update_list);
2159 	INIT_LIST_HEAD(insert_list);
2160 	INIT_LIST_HEAD(remove_list);
2161 	INIT_LIST_HEAD(&new_list);
2162 	INIT_LIST_HEAD(remap_list);
2163 
2164 	node = interval_tree_iter_first(&svms->objects, start, last);
2165 	while (node) {
2166 		struct interval_tree_node *next;
2167 		unsigned long next_start;
2168 
2169 		pr_debug("found overlap node [0x%lx 0x%lx]\n", node->start,
2170 			 node->last);
2171 
2172 		prange = container_of(node, struct svm_range, it_node);
2173 		next = interval_tree_iter_next(node, start, last);
2174 		next_start = min(node->last, last) + 1;
2175 
2176 		if (svm_range_is_same_attrs(p, prange, nattr, attrs) &&
2177 		    prange->mapped_to_gpu) {
2178 			/* nothing to do */
2179 		} else if (node->start < start || node->last > last) {
2180 			/* node intersects the update range and its attributes
2181 			 * will change. Clone and split it, apply updates only
2182 			 * to the overlapping part
2183 			 */
2184 			struct svm_range *old = prange;
2185 
2186 			prange = svm_range_clone(old);
2187 			if (!prange) {
2188 				r = -ENOMEM;
2189 				goto out;
2190 			}
2191 
2192 			list_add(&old->update_list, remove_list);
2193 			list_add(&prange->list, insert_list);
2194 			list_add(&prange->update_list, update_list);
2195 
2196 			if (node->start < start) {
2197 				pr_debug("change old range start\n");
2198 				r = svm_range_split_head(prange, start,
2199 							 insert_list, remap_list);
2200 				if (r)
2201 					goto out;
2202 			}
2203 			if (node->last > last) {
2204 				pr_debug("change old range last\n");
2205 				r = svm_range_split_tail(prange, last,
2206 							 insert_list, remap_list);
2207 				if (r)
2208 					goto out;
2209 			}
2210 		} else {
2211 			/* The node is contained within start..last,
2212 			 * just update it
2213 			 */
2214 			list_add(&prange->update_list, update_list);
2215 		}
2216 
2217 		/* insert a new node if needed */
2218 		if (node->start > start) {
2219 			r = svm_range_split_new(svms, start, node->start - 1,
2220 						READ_ONCE(max_svm_range_pages),
2221 						&new_list, update_list);
2222 			if (r)
2223 				goto out;
2224 		}
2225 
2226 		node = next;
2227 		start = next_start;
2228 	}
2229 
2230 	/* add a final range at the end if needed */
2231 	if (start <= last)
2232 		r = svm_range_split_new(svms, start, last,
2233 					READ_ONCE(max_svm_range_pages),
2234 					&new_list, update_list);
2235 
2236 out:
2237 	if (r) {
2238 		list_for_each_entry_safe(prange, tmp, insert_list, list)
2239 			svm_range_free(prange, false);
2240 		list_for_each_entry_safe(prange, tmp, &new_list, list)
2241 			svm_range_free(prange, true);
2242 	} else {
2243 		list_splice(&new_list, insert_list);
2244 	}
2245 
2246 	return r;
2247 }
2248 
2249 static void
2250 svm_range_update_notifier_and_interval_tree(struct mm_struct *mm,
2251 					    struct svm_range *prange)
2252 {
2253 	unsigned long start;
2254 	unsigned long last;
2255 
2256 	start = prange->notifier.interval_tree.start >> PAGE_SHIFT;
2257 	last = prange->notifier.interval_tree.last >> PAGE_SHIFT;
2258 
2259 	if (prange->start == start && prange->last == last)
2260 		return;
2261 
2262 	pr_debug("up notifier 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
2263 		  prange->svms, prange, start, last, prange->start,
2264 		  prange->last);
2265 
2266 	if (start != 0 && last != 0) {
2267 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
2268 		svm_range_remove_notifier(prange);
2269 	}
2270 	prange->it_node.start = prange->start;
2271 	prange->it_node.last = prange->last;
2272 
2273 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
2274 	svm_range_add_notifier_locked(mm, prange);
2275 }
2276 
2277 static void
2278 svm_range_handle_list_op(struct svm_range_list *svms, struct svm_range *prange,
2279 			 struct mm_struct *mm)
2280 {
2281 	switch (prange->work_item.op) {
2282 	case SVM_OP_NULL:
2283 		pr_debug("NULL OP 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2284 			 svms, prange, prange->start, prange->last);
2285 		break;
2286 	case SVM_OP_UNMAP_RANGE:
2287 		pr_debug("remove 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2288 			 svms, prange, prange->start, prange->last);
2289 		svm_range_unlink(prange);
2290 		svm_range_remove_notifier(prange);
2291 		svm_range_free(prange, true);
2292 		break;
2293 	case SVM_OP_UPDATE_RANGE_NOTIFIER:
2294 		pr_debug("update notifier 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2295 			 svms, prange, prange->start, prange->last);
2296 		svm_range_update_notifier_and_interval_tree(mm, prange);
2297 		break;
2298 	case SVM_OP_UPDATE_RANGE_NOTIFIER_AND_MAP:
2299 		pr_debug("update and map 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2300 			 svms, prange, prange->start, prange->last);
2301 		svm_range_update_notifier_and_interval_tree(mm, prange);
2302 		/* TODO: implement deferred validation and mapping */
2303 		break;
2304 	case SVM_OP_ADD_RANGE:
2305 		pr_debug("add 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms, prange,
2306 			 prange->start, prange->last);
2307 		svm_range_add_to_svms(prange);
2308 		svm_range_add_notifier_locked(mm, prange);
2309 		break;
2310 	case SVM_OP_ADD_RANGE_AND_MAP:
2311 		pr_debug("add and map 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms,
2312 			 prange, prange->start, prange->last);
2313 		svm_range_add_to_svms(prange);
2314 		svm_range_add_notifier_locked(mm, prange);
2315 		/* TODO: implement deferred validation and mapping */
2316 		break;
2317 	default:
2318 		WARN_ONCE(1, "Unknown prange 0x%p work op %d\n", prange,
2319 			 prange->work_item.op);
2320 	}
2321 }
2322 
2323 static void svm_range_drain_retry_fault(struct svm_range_list *svms)
2324 {
2325 	struct kfd_process_device *pdd;
2326 	struct kfd_process *p;
2327 	uint32_t i;
2328 
2329 	p = container_of(svms, struct kfd_process, svms);
2330 
2331 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2332 		pdd = p->pdds[i];
2333 		if (!pdd)
2334 			continue;
2335 
2336 		pr_debug("drain retry fault gpu %d svms %p\n", i, svms);
2337 
2338 		amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2339 				pdd->dev->adev->irq.retry_cam_enabled ?
2340 				&pdd->dev->adev->irq.ih :
2341 				&pdd->dev->adev->irq.ih1);
2342 
2343 		if (pdd->dev->adev->irq.retry_cam_enabled)
2344 			amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2345 				&pdd->dev->adev->irq.ih_soft);
2346 
2347 
2348 		pr_debug("drain retry fault gpu %d svms 0x%p done\n", i, svms);
2349 	}
2350 }
2351 
2352 static void svm_range_deferred_list_work(struct work_struct *work)
2353 {
2354 	struct svm_range_list *svms;
2355 	struct svm_range *prange;
2356 	struct mm_struct *mm;
2357 
2358 	svms = container_of(work, struct svm_range_list, deferred_list_work);
2359 	pr_debug("enter svms 0x%p\n", svms);
2360 
2361 	spin_lock(&svms->deferred_list_lock);
2362 	while (!list_empty(&svms->deferred_range_list)) {
2363 		prange = list_first_entry(&svms->deferred_range_list,
2364 					  struct svm_range, deferred_list);
2365 		spin_unlock(&svms->deferred_list_lock);
2366 
2367 		pr_debug("prange 0x%p [0x%lx 0x%lx] op %d\n", prange,
2368 			 prange->start, prange->last, prange->work_item.op);
2369 
2370 		mm = prange->work_item.mm;
2371 
2372 		mmap_write_lock(mm);
2373 
2374 		/* Remove from deferred_list must be inside mmap write lock, for
2375 		 * two race cases:
2376 		 * 1. unmap_from_cpu may change work_item.op and add the range
2377 		 *    to deferred_list again, cause use after free bug.
2378 		 * 2. svm_range_list_lock_and_flush_work may hold mmap write
2379 		 *    lock and continue because deferred_list is empty, but
2380 		 *    deferred_list work is actually waiting for mmap lock.
2381 		 */
2382 		spin_lock(&svms->deferred_list_lock);
2383 		list_del_init(&prange->deferred_list);
2384 		spin_unlock(&svms->deferred_list_lock);
2385 
2386 		mutex_lock(&svms->lock);
2387 		mutex_lock(&prange->migrate_mutex);
2388 		while (!list_empty(&prange->child_list)) {
2389 			struct svm_range *pchild;
2390 
2391 			pchild = list_first_entry(&prange->child_list,
2392 						struct svm_range, child_list);
2393 			pr_debug("child prange 0x%p op %d\n", pchild,
2394 				 pchild->work_item.op);
2395 			list_del_init(&pchild->child_list);
2396 			svm_range_handle_list_op(svms, pchild, mm);
2397 		}
2398 		mutex_unlock(&prange->migrate_mutex);
2399 
2400 		svm_range_handle_list_op(svms, prange, mm);
2401 		mutex_unlock(&svms->lock);
2402 		mmap_write_unlock(mm);
2403 
2404 		/* Pairs with mmget in svm_range_add_list_work. If dropping the
2405 		 * last mm refcount, schedule release work to avoid circular locking
2406 		 */
2407 		mmput_async(mm);
2408 
2409 		spin_lock(&svms->deferred_list_lock);
2410 	}
2411 	spin_unlock(&svms->deferred_list_lock);
2412 	pr_debug("exit svms 0x%p\n", svms);
2413 }
2414 
2415 void
2416 svm_range_add_list_work(struct svm_range_list *svms, struct svm_range *prange,
2417 			struct mm_struct *mm, enum svm_work_list_ops op)
2418 {
2419 	spin_lock(&svms->deferred_list_lock);
2420 	/* if prange is on the deferred list */
2421 	if (!list_empty(&prange->deferred_list)) {
2422 		pr_debug("update exist prange 0x%p work op %d\n", prange, op);
2423 		WARN_ONCE(prange->work_item.mm != mm, "unmatch mm\n");
2424 		if (op != SVM_OP_NULL &&
2425 		    prange->work_item.op != SVM_OP_UNMAP_RANGE)
2426 			prange->work_item.op = op;
2427 	} else {
2428 		/* Pairs with mmput in deferred_list_work.
2429 		 * If process is exiting and mm is gone, don't update mmu notifier.
2430 		 */
2431 		if (mmget_not_zero(mm)) {
2432 			prange->work_item.mm = mm;
2433 			prange->work_item.op = op;
2434 			list_add_tail(&prange->deferred_list,
2435 				      &prange->svms->deferred_range_list);
2436 			pr_debug("add prange 0x%p [0x%lx 0x%lx] to work list op %d\n",
2437 				 prange, prange->start, prange->last, op);
2438 		}
2439 	}
2440 	spin_unlock(&svms->deferred_list_lock);
2441 }
2442 
2443 void schedule_deferred_list_work(struct svm_range_list *svms)
2444 {
2445 	spin_lock(&svms->deferred_list_lock);
2446 	if (!list_empty(&svms->deferred_range_list))
2447 		schedule_work(&svms->deferred_list_work);
2448 	spin_unlock(&svms->deferred_list_lock);
2449 }
2450 
2451 static void
2452 svm_range_unmap_split(struct svm_range *parent, struct svm_range *prange, unsigned long start,
2453 		      unsigned long last)
2454 {
2455 	struct svm_range *head;
2456 	struct svm_range *tail;
2457 
2458 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2459 		pr_debug("prange 0x%p [0x%lx 0x%lx] is already freed\n", prange,
2460 			 prange->start, prange->last);
2461 		return;
2462 	}
2463 	if (start > prange->last || last < prange->start)
2464 		return;
2465 
2466 	head = tail = prange;
2467 	if (start > prange->start)
2468 		svm_range_split(prange, prange->start, start - 1, &tail);
2469 	if (last < tail->last)
2470 		svm_range_split(tail, last + 1, tail->last, &head);
2471 
2472 	if (head != prange && tail != prange) {
2473 		svm_range_add_child(parent, head, SVM_OP_UNMAP_RANGE);
2474 		svm_range_add_child(parent, tail, SVM_OP_ADD_RANGE);
2475 	} else if (tail != prange) {
2476 		svm_range_add_child(parent, tail, SVM_OP_UNMAP_RANGE);
2477 	} else if (head != prange) {
2478 		svm_range_add_child(parent, head, SVM_OP_UNMAP_RANGE);
2479 	} else if (parent != prange) {
2480 		prange->work_item.op = SVM_OP_UNMAP_RANGE;
2481 	}
2482 }
2483 
2484 static void
2485 svm_range_unmap_from_cpu(struct mm_struct *mm, struct svm_range *prange,
2486 			 unsigned long start, unsigned long last)
2487 {
2488 	uint32_t trigger = KFD_SVM_UNMAP_TRIGGER_UNMAP_FROM_CPU;
2489 	struct svm_range_list *svms;
2490 	struct svm_range *pchild;
2491 	struct kfd_process *p;
2492 	unsigned long s, l;
2493 	bool unmap_parent;
2494 	uint32_t i;
2495 
2496 	if (atomic_read(&prange->queue_refcount)) {
2497 		int r;
2498 
2499 		pr_warn("Freeing queue vital buffer 0x%lx, queue evicted\n",
2500 			prange->start << PAGE_SHIFT);
2501 		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_SVM);
2502 		if (r)
2503 			pr_debug("failed %d to quiesce KFD queues\n", r);
2504 	}
2505 
2506 	p = kfd_lookup_process_by_mm(mm);
2507 	if (!p)
2508 		return;
2509 	svms = &p->svms;
2510 
2511 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n", svms,
2512 		 prange, prange->start, prange->last, start, last);
2513 
2514 	/* calculate time stamps that are used to decide which page faults need be
2515 	 * dropped or handled before unmap pages from gpu vm
2516 	 */
2517 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2518 		struct kfd_process_device *pdd;
2519 		struct amdgpu_device *adev;
2520 		struct amdgpu_ih_ring *ih;
2521 		uint32_t checkpoint_wptr;
2522 
2523 		pdd = p->pdds[i];
2524 		if (!pdd)
2525 			continue;
2526 
2527 		adev = pdd->dev->adev;
2528 
2529 		/* Check and drain ih1 ring if cam not available */
2530 		if (adev->irq.ih1.ring_size) {
2531 			ih = &adev->irq.ih1;
2532 			checkpoint_wptr = amdgpu_ih_get_wptr(adev, ih);
2533 			if (ih->rptr != checkpoint_wptr) {
2534 				svms->checkpoint_ts[i] =
2535 					amdgpu_ih_decode_iv_ts(adev, ih, checkpoint_wptr, -1);
2536 				continue;
2537 			}
2538 		}
2539 
2540 		/* check if dev->irq.ih_soft is not empty */
2541 		ih = &adev->irq.ih_soft;
2542 		checkpoint_wptr = amdgpu_ih_get_wptr(adev, ih);
2543 		if (ih->rptr != checkpoint_wptr)
2544 			svms->checkpoint_ts[i] = amdgpu_ih_decode_iv_ts(adev, ih, checkpoint_wptr, -1);
2545 	}
2546 
2547 	unmap_parent = start <= prange->start && last >= prange->last;
2548 
2549 	list_for_each_entry(pchild, &prange->child_list, child_list) {
2550 		mutex_lock_nested(&pchild->lock, 1);
2551 		s = max(start, pchild->start);
2552 		l = min(last, pchild->last);
2553 		if (l >= s)
2554 			svm_range_unmap_from_gpus(pchild, s, l, trigger);
2555 		svm_range_unmap_split(prange, pchild, start, last);
2556 		mutex_unlock(&pchild->lock);
2557 	}
2558 	s = max(start, prange->start);
2559 	l = min(last, prange->last);
2560 	if (l >= s)
2561 		svm_range_unmap_from_gpus(prange, s, l, trigger);
2562 	svm_range_unmap_split(prange, prange, start, last);
2563 
2564 	if (unmap_parent)
2565 		svm_range_add_list_work(svms, prange, mm, SVM_OP_UNMAP_RANGE);
2566 	else
2567 		svm_range_add_list_work(svms, prange, mm,
2568 					SVM_OP_UPDATE_RANGE_NOTIFIER);
2569 	schedule_deferred_list_work(svms);
2570 
2571 	kfd_unref_process(p);
2572 }
2573 
2574 /**
2575  * svm_range_cpu_invalidate_pagetables - interval notifier callback
2576  * @mni: mmu_interval_notifier struct
2577  * @range: mmu_notifier_range struct
2578  * @cur_seq: value to pass to mmu_interval_set_seq()
2579  *
2580  * If event is MMU_NOTIFY_UNMAP, this is from CPU unmap range, otherwise, it
2581  * is from migration, or CPU page invalidation callback.
2582  *
2583  * For unmap event, unmap range from GPUs, remove prange from svms in a delayed
2584  * work thread, and split prange if only part of prange is unmapped.
2585  *
2586  * For invalidation event, if GPU retry fault is not enabled, evict the queues,
2587  * then schedule svm_range_restore_work to update GPU mapping and resume queues.
2588  * If GPU retry fault is enabled, unmap the svm range from GPU, retry fault will
2589  * update GPU mapping to recover.
2590  *
2591  * Context: mmap lock, notifier_invalidate_start lock are held
2592  *          for invalidate event, prange lock is held if this is from migration
2593  */
2594 static bool
2595 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
2596 				    const struct mmu_notifier_range *range,
2597 				    unsigned long cur_seq)
2598 {
2599 	struct svm_range *prange;
2600 	unsigned long start;
2601 	unsigned long last;
2602 
2603 	if (range->event == MMU_NOTIFY_RELEASE)
2604 		return true;
2605 
2606 	start = mni->interval_tree.start;
2607 	last = mni->interval_tree.last;
2608 	start = max(start, range->start) >> PAGE_SHIFT;
2609 	last = min(last, range->end - 1) >> PAGE_SHIFT;
2610 	pr_debug("[0x%lx 0x%lx] range[0x%lx 0x%lx] notifier[0x%lx 0x%lx] %d\n",
2611 		 start, last, range->start >> PAGE_SHIFT,
2612 		 (range->end - 1) >> PAGE_SHIFT,
2613 		 mni->interval_tree.start >> PAGE_SHIFT,
2614 		 mni->interval_tree.last >> PAGE_SHIFT, range->event);
2615 
2616 	prange = container_of(mni, struct svm_range, notifier);
2617 
2618 	svm_range_lock(prange);
2619 	mmu_interval_set_seq(mni, cur_seq);
2620 
2621 	switch (range->event) {
2622 	case MMU_NOTIFY_UNMAP:
2623 		svm_range_unmap_from_cpu(mni->mm, prange, start, last);
2624 		break;
2625 	default:
2626 		svm_range_evict(prange, mni->mm, start, last, range->event);
2627 		break;
2628 	}
2629 
2630 	svm_range_unlock(prange);
2631 
2632 	return true;
2633 }
2634 
2635 /**
2636  * svm_range_from_addr - find svm range from fault address
2637  * @svms: svm range list header
2638  * @addr: address to search range interval tree, in pages
2639  * @parent: parent range if range is on child list
2640  *
2641  * Context: The caller must hold svms->lock
2642  *
2643  * Return: the svm_range found or NULL
2644  */
2645 struct svm_range *
2646 svm_range_from_addr(struct svm_range_list *svms, unsigned long addr,
2647 		    struct svm_range **parent)
2648 {
2649 	struct interval_tree_node *node;
2650 	struct svm_range *prange;
2651 	struct svm_range *pchild;
2652 
2653 	node = interval_tree_iter_first(&svms->objects, addr, addr);
2654 	if (!node)
2655 		return NULL;
2656 
2657 	prange = container_of(node, struct svm_range, it_node);
2658 	pr_debug("address 0x%lx prange [0x%lx 0x%lx] node [0x%lx 0x%lx]\n",
2659 		 addr, prange->start, prange->last, node->start, node->last);
2660 
2661 	if (addr >= prange->start && addr <= prange->last) {
2662 		if (parent)
2663 			*parent = prange;
2664 		return prange;
2665 	}
2666 	list_for_each_entry(pchild, &prange->child_list, child_list)
2667 		if (addr >= pchild->start && addr <= pchild->last) {
2668 			pr_debug("found address 0x%lx pchild [0x%lx 0x%lx]\n",
2669 				 addr, pchild->start, pchild->last);
2670 			if (parent)
2671 				*parent = prange;
2672 			return pchild;
2673 		}
2674 
2675 	return NULL;
2676 }
2677 
2678 /* svm_range_best_restore_location - decide the best fault restore location
2679  * @prange: svm range structure
2680  * @adev: the GPU on which vm fault happened
2681  *
2682  * This is only called when xnack is on, to decide the best location to restore
2683  * the range mapping after GPU vm fault. Caller uses the best location to do
2684  * migration if actual loc is not best location, then update GPU page table
2685  * mapping to the best location.
2686  *
2687  * If the preferred loc is accessible by faulting GPU, use preferred loc.
2688  * If vm fault gpu idx is on range ACCESSIBLE bitmap, best_loc is vm fault gpu
2689  * If vm fault gpu idx is on range ACCESSIBLE_IN_PLACE bitmap, then
2690  *    if range actual loc is cpu, best_loc is cpu
2691  *    if vm fault gpu is on xgmi same hive of range actual loc gpu, best_loc is
2692  *    range actual loc.
2693  * Otherwise, GPU no access, best_loc is -1.
2694  *
2695  * Return:
2696  * -1 means vm fault GPU no access
2697  * 0 for CPU or GPU id
2698  */
2699 static int32_t
2700 svm_range_best_restore_location(struct svm_range *prange,
2701 				struct kfd_node *node,
2702 				int32_t *gpuidx)
2703 {
2704 	struct kfd_node *bo_node, *preferred_node;
2705 	struct kfd_process *p;
2706 	uint32_t gpuid;
2707 	int r;
2708 
2709 	p = container_of(prange->svms, struct kfd_process, svms);
2710 
2711 	r = kfd_process_gpuid_from_node(p, node, &gpuid, gpuidx);
2712 	if (r < 0) {
2713 		pr_debug("failed to get gpuid from kgd\n");
2714 		return -1;
2715 	}
2716 
2717 	if (node->adev->apu_prefer_gtt)
2718 		return 0;
2719 
2720 	if (prange->preferred_loc == gpuid ||
2721 	    prange->preferred_loc == KFD_IOCTL_SVM_LOCATION_SYSMEM) {
2722 		return prange->preferred_loc;
2723 	} else if (prange->preferred_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
2724 		preferred_node = svm_range_get_node_by_id(prange, prange->preferred_loc);
2725 		if (preferred_node && svm_nodes_in_same_hive(node, preferred_node))
2726 			return prange->preferred_loc;
2727 		/* fall through */
2728 	}
2729 
2730 	if (test_bit(*gpuidx, prange->bitmap_access))
2731 		return gpuid;
2732 
2733 	if (test_bit(*gpuidx, prange->bitmap_aip)) {
2734 		if (!prange->actual_loc)
2735 			return 0;
2736 
2737 		bo_node = svm_range_get_node_by_id(prange, prange->actual_loc);
2738 		if (bo_node && svm_nodes_in_same_hive(node, bo_node))
2739 			return prange->actual_loc;
2740 		else
2741 			return 0;
2742 	}
2743 
2744 	return -1;
2745 }
2746 
2747 static int
2748 svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
2749 			       unsigned long *start, unsigned long *last,
2750 			       bool *is_heap_stack)
2751 {
2752 	struct vm_area_struct *vma;
2753 	struct interval_tree_node *node;
2754 	struct rb_node *rb_node;
2755 	unsigned long start_limit, end_limit;
2756 
2757 	vma = vma_lookup(p->mm, addr << PAGE_SHIFT);
2758 	if (!vma) {
2759 		pr_debug("VMA does not exist in address [0x%llx]\n", addr);
2760 		return -EFAULT;
2761 	}
2762 
2763 	*is_heap_stack = vma_is_initial_heap(vma) || vma_is_initial_stack(vma);
2764 
2765 	start_limit = max(vma->vm_start >> PAGE_SHIFT,
2766 		      (unsigned long)ALIGN_DOWN(addr, 1UL << p->svms.default_granularity));
2767 	end_limit = min(vma->vm_end >> PAGE_SHIFT,
2768 		    (unsigned long)ALIGN(addr + 1, 1UL << p->svms.default_granularity));
2769 
2770 	/* First range that starts after the fault address */
2771 	node = interval_tree_iter_first(&p->svms.objects, addr + 1, ULONG_MAX);
2772 	if (node) {
2773 		end_limit = min(end_limit, node->start);
2774 		/* Last range that ends before the fault address */
2775 		rb_node = rb_prev(&node->rb);
2776 	} else {
2777 		/* Last range must end before addr because
2778 		 * there was no range after addr
2779 		 */
2780 		rb_node = rb_last(&p->svms.objects.rb_root);
2781 	}
2782 	if (rb_node) {
2783 		node = container_of(rb_node, struct interval_tree_node, rb);
2784 		if (node->last >= addr) {
2785 			WARN(1, "Overlap with prev node and page fault addr\n");
2786 			return -EFAULT;
2787 		}
2788 		start_limit = max(start_limit, node->last + 1);
2789 	}
2790 
2791 	*start = start_limit;
2792 	*last = end_limit - 1;
2793 
2794 	pr_debug("vma [0x%lx 0x%lx] range [0x%lx 0x%lx] is_heap_stack %d\n",
2795 		 vma->vm_start >> PAGE_SHIFT, vma->vm_end >> PAGE_SHIFT,
2796 		 *start, *last, *is_heap_stack);
2797 
2798 	return 0;
2799 }
2800 
2801 static int
2802 svm_range_check_vm_userptr(struct kfd_process *p, uint64_t start, uint64_t last,
2803 			   uint64_t *bo_s, uint64_t *bo_l)
2804 {
2805 	struct amdgpu_bo_va_mapping *mapping;
2806 	struct interval_tree_node *node;
2807 	struct amdgpu_bo *bo = NULL;
2808 	unsigned long userptr;
2809 	uint32_t i;
2810 	int r;
2811 
2812 	for (i = 0; i < p->n_pdds; i++) {
2813 		struct amdgpu_vm *vm;
2814 
2815 		if (!p->pdds[i]->drm_priv)
2816 			continue;
2817 
2818 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
2819 		r = amdgpu_bo_reserve(vm->root.bo, false);
2820 		if (r)
2821 			return r;
2822 
2823 		/* Check userptr by searching entire vm->va interval tree */
2824 		node = interval_tree_iter_first(&vm->va, 0, ~0ULL);
2825 		while (node) {
2826 			mapping = container_of((struct rb_node *)node,
2827 					       struct amdgpu_bo_va_mapping, rb);
2828 			bo = mapping->bo_va->base.bo;
2829 
2830 			if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm,
2831 							 start << PAGE_SHIFT,
2832 							 last << PAGE_SHIFT,
2833 							 &userptr)) {
2834 				node = interval_tree_iter_next(node, 0, ~0ULL);
2835 				continue;
2836 			}
2837 
2838 			pr_debug("[0x%llx 0x%llx] already userptr mapped\n",
2839 				 start, last);
2840 			if (bo_s && bo_l) {
2841 				*bo_s = userptr >> PAGE_SHIFT;
2842 				*bo_l = *bo_s + bo->tbo.ttm->num_pages - 1;
2843 			}
2844 			amdgpu_bo_unreserve(vm->root.bo);
2845 			return -EADDRINUSE;
2846 		}
2847 		amdgpu_bo_unreserve(vm->root.bo);
2848 	}
2849 	return 0;
2850 }
2851 
2852 static struct
2853 svm_range *svm_range_create_unregistered_range(struct kfd_node *node,
2854 						struct kfd_process *p,
2855 						struct mm_struct *mm,
2856 						int64_t addr)
2857 {
2858 	struct svm_range *prange = NULL;
2859 	unsigned long start, last;
2860 	uint32_t gpuid, gpuidx;
2861 	bool is_heap_stack;
2862 	uint64_t bo_s = 0;
2863 	uint64_t bo_l = 0;
2864 	int r;
2865 
2866 	if (svm_range_get_range_boundaries(p, addr, &start, &last,
2867 					   &is_heap_stack))
2868 		return NULL;
2869 
2870 	r = svm_range_check_vm(p, start, last, &bo_s, &bo_l);
2871 	if (r != -EADDRINUSE)
2872 		r = svm_range_check_vm_userptr(p, start, last, &bo_s, &bo_l);
2873 
2874 	if (r == -EADDRINUSE) {
2875 		if (addr >= bo_s && addr <= bo_l)
2876 			return NULL;
2877 
2878 		/* Create one page svm range if 2MB range overlapping */
2879 		start = addr;
2880 		last = addr;
2881 	}
2882 
2883 	prange = svm_range_new(&p->svms, start, last, true);
2884 	if (!prange) {
2885 		pr_debug("Failed to create prange in address [0x%llx]\n", addr);
2886 		return NULL;
2887 	}
2888 	if (kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx)) {
2889 		pr_debug("failed to get gpuid from kgd\n");
2890 		svm_range_free(prange, true);
2891 		return NULL;
2892 	}
2893 
2894 	if (is_heap_stack)
2895 		prange->preferred_loc = KFD_IOCTL_SVM_LOCATION_SYSMEM;
2896 
2897 	svm_range_add_to_svms(prange);
2898 	svm_range_add_notifier_locked(mm, prange);
2899 
2900 	return prange;
2901 }
2902 
2903 /* svm_range_skip_recover - decide if prange can be recovered
2904  * @prange: svm range structure
2905  *
2906  * GPU vm retry fault handle skip recover the range for cases:
2907  * 1. prange is on deferred list to be removed after unmap, it is stale fault,
2908  *    deferred list work will drain the stale fault before free the prange.
2909  * 2. prange is on deferred list to add interval notifier after split, or
2910  * 3. prange is child range, it is split from parent prange, recover later
2911  *    after interval notifier is added.
2912  *
2913  * Return: true to skip recover, false to recover
2914  */
2915 static bool svm_range_skip_recover(struct svm_range *prange)
2916 {
2917 	struct svm_range_list *svms = prange->svms;
2918 
2919 	spin_lock(&svms->deferred_list_lock);
2920 	if (list_empty(&prange->deferred_list) &&
2921 	    list_empty(&prange->child_list)) {
2922 		spin_unlock(&svms->deferred_list_lock);
2923 		return false;
2924 	}
2925 	spin_unlock(&svms->deferred_list_lock);
2926 
2927 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2928 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] unmapped\n",
2929 			 svms, prange, prange->start, prange->last);
2930 		return true;
2931 	}
2932 	if (prange->work_item.op == SVM_OP_ADD_RANGE_AND_MAP ||
2933 	    prange->work_item.op == SVM_OP_ADD_RANGE) {
2934 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] not added yet\n",
2935 			 svms, prange, prange->start, prange->last);
2936 		return true;
2937 	}
2938 	return false;
2939 }
2940 
2941 static void
2942 svm_range_count_fault(struct kfd_node *node, struct kfd_process *p,
2943 		      int32_t gpuidx)
2944 {
2945 	struct kfd_process_device *pdd;
2946 
2947 	/* fault is on different page of same range
2948 	 * or fault is skipped to recover later
2949 	 * or fault is on invalid virtual address
2950 	 */
2951 	if (gpuidx == MAX_GPU_INSTANCE) {
2952 		uint32_t gpuid;
2953 		int r;
2954 
2955 		r = kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx);
2956 		if (r < 0)
2957 			return;
2958 	}
2959 
2960 	/* fault is recovered
2961 	 * or fault cannot recover because GPU no access on the range
2962 	 */
2963 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
2964 	if (pdd)
2965 		WRITE_ONCE(pdd->faults, pdd->faults + 1);
2966 }
2967 
2968 static bool
2969 svm_fault_allowed(struct vm_area_struct *vma, bool write_fault)
2970 {
2971 	unsigned long requested = VM_READ;
2972 
2973 	if (write_fault)
2974 		requested |= VM_WRITE;
2975 
2976 	pr_debug("requested 0x%lx, vma permission flags 0x%lx\n", requested,
2977 		vma->vm_flags);
2978 	return (vma->vm_flags & requested) == requested;
2979 }
2980 
2981 int
2982 svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
2983 			uint32_t vmid, uint32_t node_id,
2984 			uint64_t addr, uint64_t ts, bool write_fault)
2985 {
2986 	unsigned long start, last, size;
2987 	struct mm_struct *mm = NULL;
2988 	struct svm_range_list *svms;
2989 	struct svm_range *prange;
2990 	struct kfd_process *p;
2991 	ktime_t timestamp = ktime_get_boottime();
2992 	struct kfd_node *node;
2993 	int32_t best_loc;
2994 	int32_t gpuid, gpuidx = MAX_GPU_INSTANCE;
2995 	bool write_locked = false;
2996 	struct vm_area_struct *vma;
2997 	bool migration = false;
2998 	int r = 0;
2999 
3000 	if (!KFD_IS_SVM_API_SUPPORTED(adev)) {
3001 		pr_debug("device does not support SVM\n");
3002 		return -EFAULT;
3003 	}
3004 
3005 	p = kfd_lookup_process_by_pasid(pasid, NULL);
3006 	if (!p) {
3007 		pr_debug("kfd process not founded pasid 0x%x\n", pasid);
3008 		return 0;
3009 	}
3010 	svms = &p->svms;
3011 
3012 	pr_debug("restoring svms 0x%p fault address 0x%llx\n", svms, addr);
3013 
3014 	if (atomic_read(&svms->drain_pagefaults)) {
3015 		pr_debug("page fault handling disabled, drop fault 0x%llx\n", addr);
3016 		r = 0;
3017 		goto out;
3018 	}
3019 
3020 	node = kfd_node_by_irq_ids(adev, node_id, vmid);
3021 	if (!node) {
3022 		pr_debug("kfd node does not exist node_id: %d, vmid: %d\n", node_id,
3023 			 vmid);
3024 		r = -EFAULT;
3025 		goto out;
3026 	}
3027 
3028 	if (kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx)) {
3029 		pr_debug("failed to get gpuid/gpuidex for node_id: %d\n", node_id);
3030 		r = -EFAULT;
3031 		goto out;
3032 	}
3033 
3034 	if (!p->xnack_enabled) {
3035 		pr_debug("XNACK not enabled for pasid 0x%x\n", pasid);
3036 		r = -EFAULT;
3037 		goto out;
3038 	}
3039 
3040 	/* p->lead_thread is available as kfd_process_wq_release flush the work
3041 	 * before releasing task ref.
3042 	 */
3043 	mm = get_task_mm(p->lead_thread);
3044 	if (!mm) {
3045 		pr_debug("svms 0x%p failed to get mm\n", svms);
3046 		r = 0;
3047 		goto out;
3048 	}
3049 
3050 	mmap_read_lock(mm);
3051 retry_write_locked:
3052 	mutex_lock(&svms->lock);
3053 
3054 	/* check if this page fault time stamp is before svms->checkpoint_ts */
3055 	if (svms->checkpoint_ts[gpuidx] != 0) {
3056 		if (amdgpu_ih_ts_after_or_equal(ts,  svms->checkpoint_ts[gpuidx])) {
3057 			pr_debug("draining retry fault, drop fault 0x%llx\n", addr);
3058 			if (write_locked)
3059 				mmap_write_downgrade(mm);
3060 			r = -EAGAIN;
3061 			goto out_unlock_svms;
3062 		} else {
3063 			/* ts is after svms->checkpoint_ts now, reset svms->checkpoint_ts
3064 			 * to zero to avoid following ts wrap around give wrong comparing
3065 			 */
3066 			svms->checkpoint_ts[gpuidx] = 0;
3067 		}
3068 	}
3069 
3070 	prange = svm_range_from_addr(svms, addr, NULL);
3071 	if (!prange) {
3072 		pr_debug("failed to find prange svms 0x%p address [0x%llx]\n",
3073 			 svms, addr);
3074 		if (!write_locked) {
3075 			/* Need the write lock to create new range with MMU notifier.
3076 			 * Also flush pending deferred work to make sure the interval
3077 			 * tree is up to date before we add a new range
3078 			 */
3079 			mutex_unlock(&svms->lock);
3080 			mmap_read_unlock(mm);
3081 			mmap_write_lock(mm);
3082 			write_locked = true;
3083 			goto retry_write_locked;
3084 		}
3085 		prange = svm_range_create_unregistered_range(node, p, mm, addr);
3086 		if (!prange) {
3087 			pr_debug("failed to create unregistered range svms 0x%p address [0x%llx]\n",
3088 				 svms, addr);
3089 			mmap_write_downgrade(mm);
3090 			r = -EFAULT;
3091 			goto out_unlock_svms;
3092 		}
3093 	}
3094 	if (write_locked)
3095 		mmap_write_downgrade(mm);
3096 
3097 	mutex_lock(&prange->migrate_mutex);
3098 
3099 	if (svm_range_skip_recover(prange)) {
3100 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
3101 		r = 0;
3102 		goto out_unlock_range;
3103 	}
3104 
3105 	/* skip duplicate vm fault on different pages of same range */
3106 	if (ktime_before(timestamp, ktime_add_ns(prange->validate_timestamp,
3107 				AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING))) {
3108 		pr_debug("svms 0x%p [0x%lx %lx] already restored\n",
3109 			 svms, prange->start, prange->last);
3110 		r = 0;
3111 		goto out_unlock_range;
3112 	}
3113 
3114 	/* __do_munmap removed VMA, return success as we are handling stale
3115 	 * retry fault.
3116 	 */
3117 	vma = vma_lookup(mm, addr << PAGE_SHIFT);
3118 	if (!vma) {
3119 		pr_debug("address 0x%llx VMA is removed\n", addr);
3120 		r = 0;
3121 		goto out_unlock_range;
3122 	}
3123 
3124 	if (!svm_fault_allowed(vma, write_fault)) {
3125 		pr_debug("fault addr 0x%llx no %s permission\n", addr,
3126 			write_fault ? "write" : "read");
3127 		r = -EPERM;
3128 		goto out_unlock_range;
3129 	}
3130 
3131 	best_loc = svm_range_best_restore_location(prange, node, &gpuidx);
3132 	if (best_loc == -1) {
3133 		pr_debug("svms %p failed get best restore loc [0x%lx 0x%lx]\n",
3134 			 svms, prange->start, prange->last);
3135 		r = -EACCES;
3136 		goto out_unlock_range;
3137 	}
3138 
3139 	pr_debug("svms %p [0x%lx 0x%lx] best restore 0x%x, actual loc 0x%x\n",
3140 		 svms, prange->start, prange->last, best_loc,
3141 		 prange->actual_loc);
3142 
3143 	kfd_smi_event_page_fault_start(node, p->lead_thread->pid, addr,
3144 				       write_fault, timestamp);
3145 
3146 	/* Align migration range start and size to granularity size */
3147 	size = 1UL << prange->granularity;
3148 	start = max_t(unsigned long, ALIGN_DOWN(addr, size), prange->start);
3149 	last = min_t(unsigned long, ALIGN(addr + 1, size) - 1, prange->last);
3150 	if (prange->actual_loc != 0 || best_loc != 0) {
3151 		if (best_loc) {
3152 			r = svm_migrate_to_vram(prange, best_loc, start, last,
3153 					mm, KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU);
3154 			if (r) {
3155 				pr_debug("svm_migrate_to_vram failed (%d) at %llx, falling back to system memory\n",
3156 					 r, addr);
3157 				/* Fallback to system memory if migration to
3158 				 * VRAM failed
3159 				 */
3160 				if (prange->actual_loc && prange->actual_loc != best_loc)
3161 					r = svm_migrate_vram_to_ram(prange, mm, start, last,
3162 						KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU, NULL);
3163 				else
3164 					r = 0;
3165 			}
3166 		} else {
3167 			r = svm_migrate_vram_to_ram(prange, mm, start, last,
3168 					KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU, NULL);
3169 		}
3170 		if (r) {
3171 			pr_debug("failed %d to migrate svms %p [0x%lx 0x%lx]\n",
3172 				 r, svms, start, last);
3173 			goto out_migrate_fail;
3174 		} else {
3175 			migration = true;
3176 		}
3177 	}
3178 
3179 	r = svm_range_validate_and_map(mm, start, last, prange, gpuidx, false,
3180 				       false, false);
3181 	if (r)
3182 		pr_debug("failed %d to map svms 0x%p [0x%lx 0x%lx] to gpus\n",
3183 			 r, svms, start, last);
3184 
3185 out_migrate_fail:
3186 	kfd_smi_event_page_fault_end(node, p->lead_thread->pid, addr,
3187 				     migration);
3188 
3189 out_unlock_range:
3190 	mutex_unlock(&prange->migrate_mutex);
3191 out_unlock_svms:
3192 	mutex_unlock(&svms->lock);
3193 	mmap_read_unlock(mm);
3194 
3195 	if (r != -EAGAIN)
3196 		svm_range_count_fault(node, p, gpuidx);
3197 
3198 	mmput(mm);
3199 out:
3200 	kfd_unref_process(p);
3201 
3202 	if (r == -EAGAIN) {
3203 		pr_debug("recover vm fault later\n");
3204 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
3205 		r = 0;
3206 	}
3207 	return r;
3208 }
3209 
3210 int
3211 svm_range_switch_xnack_reserve_mem(struct kfd_process *p, bool xnack_enabled)
3212 {
3213 	struct svm_range *prange, *pchild;
3214 	uint64_t reserved_size = 0;
3215 	uint64_t size;
3216 	int r = 0;
3217 
3218 	pr_debug("switching xnack from %d to %d\n", p->xnack_enabled, xnack_enabled);
3219 
3220 	mutex_lock(&p->svms.lock);
3221 
3222 	list_for_each_entry(prange, &p->svms.list, list) {
3223 		svm_range_lock(prange);
3224 		list_for_each_entry(pchild, &prange->child_list, child_list) {
3225 			size = (pchild->last - pchild->start + 1) << PAGE_SHIFT;
3226 			if (xnack_enabled) {
3227 				amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3228 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3229 			} else {
3230 				r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3231 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3232 				if (r)
3233 					goto out_unlock;
3234 				reserved_size += size;
3235 			}
3236 		}
3237 
3238 		size = (prange->last - prange->start + 1) << PAGE_SHIFT;
3239 		if (xnack_enabled) {
3240 			amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3241 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3242 		} else {
3243 			r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3244 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3245 			if (r)
3246 				goto out_unlock;
3247 			reserved_size += size;
3248 		}
3249 out_unlock:
3250 		svm_range_unlock(prange);
3251 		if (r)
3252 			break;
3253 	}
3254 
3255 	if (r)
3256 		amdgpu_amdkfd_unreserve_mem_limit(NULL, reserved_size,
3257 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3258 	else
3259 		/* Change xnack mode must be inside svms lock, to avoid race with
3260 		 * svm_range_deferred_list_work unreserve memory in parallel.
3261 		 */
3262 		p->xnack_enabled = xnack_enabled;
3263 
3264 	mutex_unlock(&p->svms.lock);
3265 	return r;
3266 }
3267 
3268 void svm_range_list_fini(struct kfd_process *p)
3269 {
3270 	struct svm_range *prange;
3271 	struct svm_range *next;
3272 
3273 	pr_debug("process pid %d svms 0x%p\n", p->lead_thread->pid,
3274 		 &p->svms);
3275 
3276 	cancel_delayed_work_sync(&p->svms.restore_work);
3277 
3278 	/* Ensure list work is finished before process is destroyed */
3279 	flush_work(&p->svms.deferred_list_work);
3280 
3281 	/*
3282 	 * Ensure no retry fault comes in afterwards, as page fault handler will
3283 	 * not find kfd process and take mm lock to recover fault.
3284 	 * stop kfd page fault handing, then wait pending page faults got drained
3285 	 */
3286 	atomic_set(&p->svms.drain_pagefaults, 1);
3287 	svm_range_drain_retry_fault(&p->svms);
3288 
3289 	list_for_each_entry_safe(prange, next, &p->svms.list, list) {
3290 		svm_range_unlink(prange);
3291 		svm_range_remove_notifier(prange);
3292 		svm_range_free(prange, true);
3293 	}
3294 
3295 	mutex_destroy(&p->svms.lock);
3296 
3297 	pr_debug("process pid %d svms 0x%p done\n",
3298 		p->lead_thread->pid, &p->svms);
3299 }
3300 
3301 int svm_range_list_init(struct kfd_process *p)
3302 {
3303 	struct svm_range_list *svms = &p->svms;
3304 	int i;
3305 
3306 	svms->objects = RB_ROOT_CACHED;
3307 	mutex_init(&svms->lock);
3308 	INIT_LIST_HEAD(&svms->list);
3309 	atomic_set(&svms->evicted_ranges, 0);
3310 	atomic_set(&svms->drain_pagefaults, 0);
3311 	INIT_DELAYED_WORK(&svms->restore_work, svm_range_restore_work);
3312 	INIT_WORK(&svms->deferred_list_work, svm_range_deferred_list_work);
3313 	INIT_LIST_HEAD(&svms->deferred_range_list);
3314 	INIT_LIST_HEAD(&svms->criu_svm_metadata_list);
3315 	spin_lock_init(&svms->deferred_list_lock);
3316 
3317 	for (i = 0; i < p->n_pdds; i++)
3318 		if (KFD_IS_SVM_API_SUPPORTED(p->pdds[i]->dev->adev))
3319 			bitmap_set(svms->bitmap_supported, i, 1);
3320 
3321 	 /* Value of default granularity cannot exceed 0x1B, the
3322 	  * number of pages supported by a 4-level paging table
3323 	  */
3324 	svms->default_granularity = min_t(u8, amdgpu_svm_default_granularity, 0x1B);
3325 	pr_debug("Default SVM Granularity to use: %d\n", svms->default_granularity);
3326 
3327 	return 0;
3328 }
3329 
3330 /**
3331  * svm_range_check_vm - check if virtual address range mapped already
3332  * @p: current kfd_process
3333  * @start: range start address, in pages
3334  * @last: range last address, in pages
3335  * @bo_s: mapping start address in pages if address range already mapped
3336  * @bo_l: mapping last address in pages if address range already mapped
3337  *
3338  * The purpose is to avoid virtual address ranges already allocated by
3339  * kfd_ioctl_alloc_memory_of_gpu ioctl.
3340  * It looks for each pdd in the kfd_process.
3341  *
3342  * Context: Process context
3343  *
3344  * Return 0 - OK, if the range is not mapped.
3345  * Otherwise error code:
3346  * -EADDRINUSE - if address is mapped already by kfd_ioctl_alloc_memory_of_gpu
3347  * -ERESTARTSYS - A wait for the buffer to become unreserved was interrupted by
3348  * a signal. Release all buffer reservations and return to user-space.
3349  */
3350 static int
3351 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
3352 		   uint64_t *bo_s, uint64_t *bo_l)
3353 {
3354 	struct amdgpu_bo_va_mapping *mapping;
3355 	struct interval_tree_node *node;
3356 	uint32_t i;
3357 	int r;
3358 
3359 	for (i = 0; i < p->n_pdds; i++) {
3360 		struct amdgpu_vm *vm;
3361 
3362 		if (!p->pdds[i]->drm_priv)
3363 			continue;
3364 
3365 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
3366 		r = amdgpu_bo_reserve(vm->root.bo, false);
3367 		if (r)
3368 			return r;
3369 
3370 		node = interval_tree_iter_first(&vm->va, start, last);
3371 		if (node) {
3372 			pr_debug("range [0x%llx 0x%llx] already TTM mapped\n",
3373 				 start, last);
3374 			mapping = container_of((struct rb_node *)node,
3375 					       struct amdgpu_bo_va_mapping, rb);
3376 			if (bo_s && bo_l) {
3377 				*bo_s = mapping->start;
3378 				*bo_l = mapping->last;
3379 			}
3380 			amdgpu_bo_unreserve(vm->root.bo);
3381 			return -EADDRINUSE;
3382 		}
3383 		amdgpu_bo_unreserve(vm->root.bo);
3384 	}
3385 
3386 	return 0;
3387 }
3388 
3389 /**
3390  * svm_range_is_valid - check if virtual address range is valid
3391  * @p: current kfd_process
3392  * @start: range start address, in pages
3393  * @size: range size, in pages
3394  *
3395  * Valid virtual address range means it belongs to one or more VMAs
3396  *
3397  * Context: Process context
3398  *
3399  * Return:
3400  *  0 - OK, otherwise error code
3401  */
3402 static int
3403 svm_range_is_valid(struct kfd_process *p, uint64_t start, uint64_t size)
3404 {
3405 	const unsigned long device_vma = VM_IO | VM_PFNMAP | VM_MIXEDMAP;
3406 	struct vm_area_struct *vma;
3407 	unsigned long end;
3408 	unsigned long start_unchg = start;
3409 
3410 	start <<= PAGE_SHIFT;
3411 	end = start + (size << PAGE_SHIFT);
3412 	do {
3413 		vma = vma_lookup(p->mm, start);
3414 		if (!vma || (vma->vm_flags & device_vma))
3415 			return -EFAULT;
3416 		start = min(end, vma->vm_end);
3417 	} while (start < end);
3418 
3419 	return svm_range_check_vm(p, start_unchg, (end - 1) >> PAGE_SHIFT, NULL,
3420 				  NULL);
3421 }
3422 
3423 /**
3424  * svm_range_best_prefetch_location - decide the best prefetch location
3425  * @prange: svm range structure
3426  *
3427  * For xnack off:
3428  * If range map to single GPU, the best prefetch location is prefetch_loc, which
3429  * can be CPU or GPU.
3430  *
3431  * If range is ACCESS or ACCESS_IN_PLACE by mGPUs, only if mGPU connection on
3432  * XGMI same hive, the best prefetch location is prefetch_loc GPU, othervise
3433  * the best prefetch location is always CPU, because GPU can not have coherent
3434  * mapping VRAM of other GPUs even with large-BAR PCIe connection.
3435  *
3436  * For xnack on:
3437  * If range is not ACCESS_IN_PLACE by mGPUs, the best prefetch location is
3438  * prefetch_loc, other GPU access will generate vm fault and trigger migration.
3439  *
3440  * If range is ACCESS_IN_PLACE by mGPUs, only if mGPU connection on XGMI same
3441  * hive, the best prefetch location is prefetch_loc GPU, otherwise the best
3442  * prefetch location is always CPU.
3443  *
3444  * Context: Process context
3445  *
3446  * Return:
3447  * 0 for CPU or GPU id
3448  */
3449 static uint32_t
3450 svm_range_best_prefetch_location(struct svm_range *prange)
3451 {
3452 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
3453 	uint32_t best_loc = prange->prefetch_loc;
3454 	struct kfd_process_device *pdd;
3455 	struct kfd_node *bo_node;
3456 	struct kfd_process *p;
3457 	uint32_t gpuidx;
3458 
3459 	p = container_of(prange->svms, struct kfd_process, svms);
3460 
3461 	if (!best_loc || best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED)
3462 		goto out;
3463 
3464 	bo_node = svm_range_get_node_by_id(prange, best_loc);
3465 	if (!bo_node) {
3466 		WARN_ONCE(1, "failed to get valid kfd node at id%x\n", best_loc);
3467 		best_loc = 0;
3468 		goto out;
3469 	}
3470 
3471 	if (bo_node->adev->apu_prefer_gtt) {
3472 		best_loc = 0;
3473 		goto out;
3474 	}
3475 
3476 	if (p->xnack_enabled)
3477 		bitmap_copy(bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
3478 	else
3479 		bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
3480 			  MAX_GPU_INSTANCE);
3481 
3482 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
3483 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
3484 		if (!pdd) {
3485 			pr_debug("failed to get device by idx 0x%x\n", gpuidx);
3486 			continue;
3487 		}
3488 
3489 		if (pdd->dev->adev == bo_node->adev)
3490 			continue;
3491 
3492 		if (!svm_nodes_in_same_hive(pdd->dev, bo_node)) {
3493 			best_loc = 0;
3494 			break;
3495 		}
3496 	}
3497 
3498 out:
3499 	pr_debug("xnack %d svms 0x%p [0x%lx 0x%lx] best loc 0x%x\n",
3500 		 p->xnack_enabled, &p->svms, prange->start, prange->last,
3501 		 best_loc);
3502 
3503 	return best_loc;
3504 }
3505 
3506 /* svm_range_trigger_migration - start page migration if prefetch loc changed
3507  * @mm: current process mm_struct
3508  * @prange: svm range structure
3509  * @migrated: output, true if migration is triggered
3510  *
3511  * If range perfetch_loc is GPU, actual loc is cpu 0, then migrate the range
3512  * from ram to vram.
3513  * If range prefetch_loc is cpu 0, actual loc is GPU, then migrate the range
3514  * from vram to ram.
3515  *
3516  * If GPU vm fault retry is not enabled, migration interact with MMU notifier
3517  * and restore work:
3518  * 1. migrate_vma_setup invalidate pages, MMU notifier callback svm_range_evict
3519  *    stops all queues, schedule restore work
3520  * 2. svm_range_restore_work wait for migration is done by
3521  *    a. svm_range_validate_vram takes prange->migrate_mutex
3522  *    b. svm_range_validate_ram HMM get pages wait for CPU fault handle returns
3523  * 3. restore work update mappings of GPU, resume all queues.
3524  *
3525  * Context: Process context
3526  *
3527  * Return:
3528  * 0 - OK, otherwise - error code of migration
3529  */
3530 static int
3531 svm_range_trigger_migration(struct mm_struct *mm, struct svm_range *prange,
3532 			    bool *migrated)
3533 {
3534 	uint32_t best_loc;
3535 	int r = 0;
3536 
3537 	*migrated = false;
3538 	best_loc = svm_range_best_prefetch_location(prange);
3539 
3540 	/* when best_loc is a gpu node and same as prange->actual_loc
3541 	 * we still need do migration as prange->actual_loc !=0 does
3542 	 * not mean all pages in prange are vram. hmm migrate will pick
3543 	 * up right pages during migration.
3544 	 */
3545 	if ((best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED) ||
3546 	    (best_loc == 0 && prange->actual_loc == 0))
3547 		return 0;
3548 
3549 	if (!best_loc) {
3550 		r = svm_migrate_vram_to_ram(prange, mm, prange->start, prange->last,
3551 					KFD_MIGRATE_TRIGGER_PREFETCH, NULL);
3552 		*migrated = !r;
3553 		return r;
3554 	}
3555 
3556 	r = svm_migrate_to_vram(prange, best_loc, prange->start, prange->last,
3557 				mm, KFD_MIGRATE_TRIGGER_PREFETCH);
3558 	*migrated = !r;
3559 
3560 	return 0;
3561 }
3562 
3563 int svm_range_schedule_evict_svm_bo(struct amdgpu_amdkfd_fence *fence)
3564 {
3565 	/* Dereferencing fence->svm_bo is safe here because the fence hasn't
3566 	 * signaled yet and we're under the protection of the fence->lock.
3567 	 * After the fence is signaled in svm_range_bo_release, we cannot get
3568 	 * here any more.
3569 	 *
3570 	 * Reference is dropped in svm_range_evict_svm_bo_worker.
3571 	 */
3572 	if (svm_bo_ref_unless_zero(fence->svm_bo)) {
3573 		WRITE_ONCE(fence->svm_bo->evicting, 1);
3574 		schedule_work(&fence->svm_bo->eviction_work);
3575 	}
3576 
3577 	return 0;
3578 }
3579 
3580 static void svm_range_evict_svm_bo_worker(struct work_struct *work)
3581 {
3582 	struct svm_range_bo *svm_bo;
3583 	struct mm_struct *mm;
3584 	int r = 0;
3585 
3586 	svm_bo = container_of(work, struct svm_range_bo, eviction_work);
3587 
3588 	if (mmget_not_zero(svm_bo->eviction_fence->mm)) {
3589 		mm = svm_bo->eviction_fence->mm;
3590 	} else {
3591 		svm_range_bo_unref(svm_bo);
3592 		return;
3593 	}
3594 
3595 	mmap_read_lock(mm);
3596 	spin_lock(&svm_bo->list_lock);
3597 	while (!list_empty(&svm_bo->range_list) && !r) {
3598 		struct svm_range *prange =
3599 				list_first_entry(&svm_bo->range_list,
3600 						struct svm_range, svm_bo_list);
3601 		int retries = 3;
3602 
3603 		list_del_init(&prange->svm_bo_list);
3604 		spin_unlock(&svm_bo->list_lock);
3605 
3606 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
3607 			 prange->start, prange->last);
3608 
3609 		mutex_lock(&prange->migrate_mutex);
3610 		do {
3611 			/* migrate all vram pages in this prange to sys ram
3612 			 * after that prange->actual_loc should be zero
3613 			 */
3614 			r = svm_migrate_vram_to_ram(prange, mm,
3615 					prange->start, prange->last,
3616 					KFD_MIGRATE_TRIGGER_TTM_EVICTION, NULL);
3617 		} while (!r && prange->actual_loc && --retries);
3618 
3619 		if (!r && prange->actual_loc)
3620 			pr_info_once("Migration failed during eviction");
3621 
3622 		if (!prange->actual_loc) {
3623 			mutex_lock(&prange->lock);
3624 			prange->svm_bo = NULL;
3625 			mutex_unlock(&prange->lock);
3626 		}
3627 		mutex_unlock(&prange->migrate_mutex);
3628 
3629 		spin_lock(&svm_bo->list_lock);
3630 	}
3631 	spin_unlock(&svm_bo->list_lock);
3632 	mmap_read_unlock(mm);
3633 	mmput(mm);
3634 
3635 	dma_fence_signal(&svm_bo->eviction_fence->base);
3636 
3637 	/* This is the last reference to svm_bo, after svm_range_vram_node_free
3638 	 * has been called in svm_migrate_vram_to_ram
3639 	 */
3640 	WARN_ONCE(!r && kref_read(&svm_bo->kref) != 1, "This was not the last reference\n");
3641 	svm_range_bo_unref(svm_bo);
3642 }
3643 
3644 static int
3645 svm_range_set_attr(struct kfd_process *p, struct mm_struct *mm,
3646 		   uint64_t start, uint64_t size, uint32_t nattr,
3647 		   struct kfd_ioctl_svm_attribute *attrs)
3648 {
3649 	struct amdkfd_process_info *process_info = p->kgd_process_info;
3650 	struct list_head update_list;
3651 	struct list_head insert_list;
3652 	struct list_head remove_list;
3653 	struct list_head remap_list;
3654 	struct svm_range_list *svms;
3655 	struct svm_range *prange;
3656 	struct svm_range *next;
3657 	bool update_mapping = false;
3658 	bool flush_tlb;
3659 	int r, ret = 0;
3660 
3661 	pr_debug("process pid %d svms 0x%p [0x%llx 0x%llx] pages 0x%llx\n",
3662 		 p->lead_thread->pid, &p->svms, start, start + size - 1, size);
3663 
3664 	r = svm_range_check_attr(p, nattr, attrs);
3665 	if (r)
3666 		return r;
3667 
3668 	svms = &p->svms;
3669 
3670 	mutex_lock(&process_info->lock);
3671 
3672 	svm_range_list_lock_and_flush_work(svms, mm);
3673 
3674 	r = svm_range_is_valid(p, start, size);
3675 	if (r) {
3676 		pr_debug("invalid range r=%d\n", r);
3677 		mmap_write_unlock(mm);
3678 		goto out;
3679 	}
3680 
3681 	mutex_lock(&svms->lock);
3682 
3683 	/* Add new range and split existing ranges as needed */
3684 	r = svm_range_add(p, start, size, nattr, attrs, &update_list,
3685 			  &insert_list, &remove_list, &remap_list);
3686 	if (r) {
3687 		mutex_unlock(&svms->lock);
3688 		mmap_write_unlock(mm);
3689 		goto out;
3690 	}
3691 	/* Apply changes as a transaction */
3692 	list_for_each_entry_safe(prange, next, &insert_list, list) {
3693 		svm_range_add_to_svms(prange);
3694 		svm_range_add_notifier_locked(mm, prange);
3695 	}
3696 	list_for_each_entry(prange, &update_list, update_list) {
3697 		svm_range_apply_attrs(p, prange, nattr, attrs, &update_mapping);
3698 		/* TODO: unmap ranges from GPU that lost access */
3699 	}
3700 	list_for_each_entry_safe(prange, next, &remove_list, update_list) {
3701 		pr_debug("unlink old 0x%p prange 0x%p [0x%lx 0x%lx]\n",
3702 			 prange->svms, prange, prange->start,
3703 			 prange->last);
3704 		svm_range_unlink(prange);
3705 		svm_range_remove_notifier(prange);
3706 		svm_range_free(prange, false);
3707 	}
3708 
3709 	mmap_write_downgrade(mm);
3710 	/* Trigger migrations and revalidate and map to GPUs as needed. If
3711 	 * this fails we may be left with partially completed actions. There
3712 	 * is no clean way of rolling back to the previous state in such a
3713 	 * case because the rollback wouldn't be guaranteed to work either.
3714 	 */
3715 	list_for_each_entry(prange, &update_list, update_list) {
3716 		bool migrated;
3717 
3718 		mutex_lock(&prange->migrate_mutex);
3719 
3720 		r = svm_range_trigger_migration(mm, prange, &migrated);
3721 		if (r)
3722 			goto out_unlock_range;
3723 
3724 		if (migrated && (!p->xnack_enabled ||
3725 		    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) &&
3726 		    prange->mapped_to_gpu) {
3727 			pr_debug("restore_work will update mappings of GPUs\n");
3728 			mutex_unlock(&prange->migrate_mutex);
3729 			continue;
3730 		}
3731 
3732 		if (!migrated && !update_mapping) {
3733 			mutex_unlock(&prange->migrate_mutex);
3734 			continue;
3735 		}
3736 
3737 		flush_tlb = !migrated && update_mapping && prange->mapped_to_gpu;
3738 
3739 		r = svm_range_validate_and_map(mm, prange->start, prange->last, prange,
3740 					       MAX_GPU_INSTANCE, true, true, flush_tlb);
3741 		if (r)
3742 			pr_debug("failed %d to map svm range\n", r);
3743 
3744 out_unlock_range:
3745 		mutex_unlock(&prange->migrate_mutex);
3746 		if (r)
3747 			ret = r;
3748 	}
3749 
3750 	list_for_each_entry(prange, &remap_list, update_list) {
3751 		pr_debug("Remapping prange 0x%p [0x%lx 0x%lx]\n",
3752 			 prange, prange->start, prange->last);
3753 		mutex_lock(&prange->migrate_mutex);
3754 		r = svm_range_validate_and_map(mm,  prange->start, prange->last, prange,
3755 					       MAX_GPU_INSTANCE, true, true, prange->mapped_to_gpu);
3756 		if (r)
3757 			pr_debug("failed %d on remap svm range\n", r);
3758 		mutex_unlock(&prange->migrate_mutex);
3759 		if (r)
3760 			ret = r;
3761 	}
3762 
3763 	dynamic_svm_range_dump(svms);
3764 
3765 	mutex_unlock(&svms->lock);
3766 	mmap_read_unlock(mm);
3767 out:
3768 	mutex_unlock(&process_info->lock);
3769 
3770 	pr_debug("process pid %d svms 0x%p [0x%llx 0x%llx] done, r=%d\n",
3771 		 p->lead_thread->pid, &p->svms, start, start + size - 1, r);
3772 
3773 	return ret ? ret : r;
3774 }
3775 
3776 static int
3777 svm_range_get_attr(struct kfd_process *p, struct mm_struct *mm,
3778 		   uint64_t start, uint64_t size, uint32_t nattr,
3779 		   struct kfd_ioctl_svm_attribute *attrs)
3780 {
3781 	DECLARE_BITMAP(bitmap_access, MAX_GPU_INSTANCE);
3782 	DECLARE_BITMAP(bitmap_aip, MAX_GPU_INSTANCE);
3783 	bool get_preferred_loc = false;
3784 	bool get_prefetch_loc = false;
3785 	bool get_granularity = false;
3786 	bool get_accessible = false;
3787 	bool get_flags = false;
3788 	uint64_t last = start + size - 1UL;
3789 	uint8_t granularity = 0xff;
3790 	struct interval_tree_node *node;
3791 	struct svm_range_list *svms;
3792 	struct svm_range *prange;
3793 	uint32_t prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3794 	uint32_t location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3795 	uint32_t flags_and = 0xffffffff;
3796 	uint32_t flags_or = 0;
3797 	int gpuidx;
3798 	uint32_t i;
3799 	int r = 0;
3800 
3801 	pr_debug("svms 0x%p [0x%llx 0x%llx] nattr 0x%x\n", &p->svms, start,
3802 		 start + size - 1, nattr);
3803 
3804 	/* Flush pending deferred work to avoid racing with deferred actions from
3805 	 * previous memory map changes (e.g. munmap). Concurrent memory map changes
3806 	 * can still race with get_attr because we don't hold the mmap lock. But that
3807 	 * would be a race condition in the application anyway, and undefined
3808 	 * behaviour is acceptable in that case.
3809 	 */
3810 	flush_work(&p->svms.deferred_list_work);
3811 
3812 	mmap_read_lock(mm);
3813 	r = svm_range_is_valid(p, start, size);
3814 	mmap_read_unlock(mm);
3815 	if (r) {
3816 		pr_debug("invalid range r=%d\n", r);
3817 		return r;
3818 	}
3819 
3820 	for (i = 0; i < nattr; i++) {
3821 		switch (attrs[i].type) {
3822 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3823 			get_preferred_loc = true;
3824 			break;
3825 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3826 			get_prefetch_loc = true;
3827 			break;
3828 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3829 			get_accessible = true;
3830 			break;
3831 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3832 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3833 			get_flags = true;
3834 			break;
3835 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3836 			get_granularity = true;
3837 			break;
3838 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
3839 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
3840 			fallthrough;
3841 		default:
3842 			pr_debug("get invalid attr type 0x%x\n", attrs[i].type);
3843 			return -EINVAL;
3844 		}
3845 	}
3846 
3847 	svms = &p->svms;
3848 
3849 	mutex_lock(&svms->lock);
3850 
3851 	node = interval_tree_iter_first(&svms->objects, start, last);
3852 	if (!node) {
3853 		pr_debug("range attrs not found return default values\n");
3854 		svm_range_set_default_attributes(svms, &location, &prefetch_loc,
3855 						 &granularity, &flags_and);
3856 		flags_or = flags_and;
3857 		if (p->xnack_enabled)
3858 			bitmap_copy(bitmap_access, svms->bitmap_supported,
3859 				    MAX_GPU_INSTANCE);
3860 		else
3861 			bitmap_zero(bitmap_access, MAX_GPU_INSTANCE);
3862 		bitmap_zero(bitmap_aip, MAX_GPU_INSTANCE);
3863 		goto fill_values;
3864 	}
3865 	bitmap_copy(bitmap_access, svms->bitmap_supported, MAX_GPU_INSTANCE);
3866 	bitmap_copy(bitmap_aip, svms->bitmap_supported, MAX_GPU_INSTANCE);
3867 
3868 	while (node) {
3869 		struct interval_tree_node *next;
3870 
3871 		prange = container_of(node, struct svm_range, it_node);
3872 		next = interval_tree_iter_next(node, start, last);
3873 
3874 		if (get_preferred_loc) {
3875 			if (prange->preferred_loc ==
3876 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3877 			    (location != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3878 			     location != prange->preferred_loc)) {
3879 				location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3880 				get_preferred_loc = false;
3881 			} else {
3882 				location = prange->preferred_loc;
3883 			}
3884 		}
3885 		if (get_prefetch_loc) {
3886 			if (prange->prefetch_loc ==
3887 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3888 			    (prefetch_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3889 			     prefetch_loc != prange->prefetch_loc)) {
3890 				prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3891 				get_prefetch_loc = false;
3892 			} else {
3893 				prefetch_loc = prange->prefetch_loc;
3894 			}
3895 		}
3896 		if (get_accessible) {
3897 			bitmap_and(bitmap_access, bitmap_access,
3898 				   prange->bitmap_access, MAX_GPU_INSTANCE);
3899 			bitmap_and(bitmap_aip, bitmap_aip,
3900 				   prange->bitmap_aip, MAX_GPU_INSTANCE);
3901 		}
3902 		if (get_flags) {
3903 			flags_and &= prange->flags;
3904 			flags_or |= prange->flags;
3905 		}
3906 
3907 		if (get_granularity && prange->granularity < granularity)
3908 			granularity = prange->granularity;
3909 
3910 		node = next;
3911 	}
3912 fill_values:
3913 	mutex_unlock(&svms->lock);
3914 
3915 	for (i = 0; i < nattr; i++) {
3916 		switch (attrs[i].type) {
3917 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3918 			attrs[i].value = location;
3919 			break;
3920 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3921 			attrs[i].value = prefetch_loc;
3922 			break;
3923 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3924 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
3925 							       attrs[i].value);
3926 			if (gpuidx < 0) {
3927 				pr_debug("invalid gpuid %x\n", attrs[i].value);
3928 				return -EINVAL;
3929 			}
3930 			if (test_bit(gpuidx, bitmap_access))
3931 				attrs[i].type = KFD_IOCTL_SVM_ATTR_ACCESS;
3932 			else if (test_bit(gpuidx, bitmap_aip))
3933 				attrs[i].type =
3934 					KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE;
3935 			else
3936 				attrs[i].type = KFD_IOCTL_SVM_ATTR_NO_ACCESS;
3937 			break;
3938 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3939 			attrs[i].value = flags_and;
3940 			break;
3941 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3942 			attrs[i].value = ~flags_or;
3943 			break;
3944 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3945 			attrs[i].value = (uint32_t)granularity;
3946 			break;
3947 		}
3948 	}
3949 
3950 	return 0;
3951 }
3952 
3953 int kfd_criu_resume_svm(struct kfd_process *p)
3954 {
3955 	struct kfd_ioctl_svm_attribute *set_attr_new, *set_attr = NULL;
3956 	int nattr_common = 4, nattr_accessibility = 1;
3957 	struct criu_svm_metadata *criu_svm_md = NULL;
3958 	struct svm_range_list *svms = &p->svms;
3959 	struct criu_svm_metadata *next = NULL;
3960 	uint32_t set_flags = 0xffffffff;
3961 	int i, j, num_attrs, ret = 0;
3962 	uint64_t set_attr_size;
3963 	struct mm_struct *mm;
3964 
3965 	if (list_empty(&svms->criu_svm_metadata_list)) {
3966 		pr_debug("No SVM data from CRIU restore stage 2\n");
3967 		return ret;
3968 	}
3969 
3970 	mm = get_task_mm(p->lead_thread);
3971 	if (!mm) {
3972 		pr_err("failed to get mm for the target process\n");
3973 		return -ESRCH;
3974 	}
3975 
3976 	num_attrs = nattr_common + (nattr_accessibility * p->n_pdds);
3977 
3978 	i = j = 0;
3979 	list_for_each_entry(criu_svm_md, &svms->criu_svm_metadata_list, list) {
3980 		pr_debug("criu_svm_md[%d]\n\tstart: 0x%llx size: 0x%llx (npages)\n",
3981 			 i, criu_svm_md->data.start_addr, criu_svm_md->data.size);
3982 
3983 		for (j = 0; j < num_attrs; j++) {
3984 			pr_debug("\ncriu_svm_md[%d]->attrs[%d].type : 0x%x\ncriu_svm_md[%d]->attrs[%d].value : 0x%x\n",
3985 				 i, j, criu_svm_md->data.attrs[j].type,
3986 				 i, j, criu_svm_md->data.attrs[j].value);
3987 			switch (criu_svm_md->data.attrs[j].type) {
3988 			/* During Checkpoint operation, the query for
3989 			 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC attribute might
3990 			 * return KFD_IOCTL_SVM_LOCATION_UNDEFINED if they were
3991 			 * not used by the range which was checkpointed. Care
3992 			 * must be taken to not restore with an invalid value
3993 			 * otherwise the gpuidx value will be invalid and
3994 			 * set_attr would eventually fail so just replace those
3995 			 * with another dummy attribute such as
3996 			 * KFD_IOCTL_SVM_ATTR_SET_FLAGS.
3997 			 */
3998 			case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3999 				if (criu_svm_md->data.attrs[j].value ==
4000 				    KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
4001 					criu_svm_md->data.attrs[j].type =
4002 						KFD_IOCTL_SVM_ATTR_SET_FLAGS;
4003 					criu_svm_md->data.attrs[j].value = 0;
4004 				}
4005 				break;
4006 			case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
4007 				set_flags = criu_svm_md->data.attrs[j].value;
4008 				break;
4009 			default:
4010 				break;
4011 			}
4012 		}
4013 
4014 		/* CLR_FLAGS is not available via get_attr during checkpoint but
4015 		 * it needs to be inserted before restoring the ranges so
4016 		 * allocate extra space for it before calling set_attr
4017 		 */
4018 		set_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4019 						(num_attrs + 1);
4020 		set_attr_new = krealloc(set_attr, set_attr_size,
4021 					    GFP_KERNEL);
4022 		if (!set_attr_new) {
4023 			ret = -ENOMEM;
4024 			goto exit;
4025 		}
4026 		set_attr = set_attr_new;
4027 
4028 		memcpy(set_attr, criu_svm_md->data.attrs, num_attrs *
4029 					sizeof(struct kfd_ioctl_svm_attribute));
4030 		set_attr[num_attrs].type = KFD_IOCTL_SVM_ATTR_CLR_FLAGS;
4031 		set_attr[num_attrs].value = ~set_flags;
4032 
4033 		ret = svm_range_set_attr(p, mm, criu_svm_md->data.start_addr,
4034 					 criu_svm_md->data.size, num_attrs + 1,
4035 					 set_attr);
4036 		if (ret) {
4037 			pr_err("CRIU: failed to set range attributes\n");
4038 			goto exit;
4039 		}
4040 
4041 		i++;
4042 	}
4043 exit:
4044 	kfree(set_attr);
4045 	list_for_each_entry_safe(criu_svm_md, next, &svms->criu_svm_metadata_list, list) {
4046 		pr_debug("freeing criu_svm_md[]\n\tstart: 0x%llx\n",
4047 						criu_svm_md->data.start_addr);
4048 		kfree(criu_svm_md);
4049 	}
4050 
4051 	mmput(mm);
4052 	return ret;
4053 
4054 }
4055 
4056 int kfd_criu_restore_svm(struct kfd_process *p,
4057 			 uint8_t __user *user_priv_ptr,
4058 			 uint64_t *priv_data_offset,
4059 			 uint64_t max_priv_data_size)
4060 {
4061 	uint64_t svm_priv_data_size, svm_object_md_size, svm_attrs_size;
4062 	int nattr_common = 4, nattr_accessibility = 1;
4063 	struct criu_svm_metadata *criu_svm_md = NULL;
4064 	struct svm_range_list *svms = &p->svms;
4065 	uint32_t num_devices;
4066 	int ret = 0;
4067 
4068 	num_devices = p->n_pdds;
4069 	/* Handle one SVM range object at a time, also the number of gpus are
4070 	 * assumed to be same on the restore node, checking must be done while
4071 	 * evaluating the topology earlier
4072 	 */
4073 
4074 	svm_attrs_size = sizeof(struct kfd_ioctl_svm_attribute) *
4075 		(nattr_common + nattr_accessibility * num_devices);
4076 	svm_object_md_size = sizeof(struct criu_svm_metadata) + svm_attrs_size;
4077 
4078 	svm_priv_data_size = sizeof(struct kfd_criu_svm_range_priv_data) +
4079 								svm_attrs_size;
4080 
4081 	criu_svm_md = kzalloc(svm_object_md_size, GFP_KERNEL);
4082 	if (!criu_svm_md) {
4083 		pr_err("failed to allocate memory to store svm metadata\n");
4084 		return -ENOMEM;
4085 	}
4086 	if (*priv_data_offset + svm_priv_data_size > max_priv_data_size) {
4087 		ret = -EINVAL;
4088 		goto exit;
4089 	}
4090 
4091 	ret = copy_from_user(&criu_svm_md->data, user_priv_ptr + *priv_data_offset,
4092 			     svm_priv_data_size);
4093 	if (ret) {
4094 		ret = -EFAULT;
4095 		goto exit;
4096 	}
4097 	*priv_data_offset += svm_priv_data_size;
4098 
4099 	list_add_tail(&criu_svm_md->list, &svms->criu_svm_metadata_list);
4100 
4101 	return 0;
4102 
4103 
4104 exit:
4105 	kfree(criu_svm_md);
4106 	return ret;
4107 }
4108 
4109 void svm_range_get_info(struct kfd_process *p, uint32_t *num_svm_ranges,
4110 			uint64_t *svm_priv_data_size)
4111 {
4112 	uint64_t total_size, accessibility_size, common_attr_size;
4113 	int nattr_common = 4, nattr_accessibility = 1;
4114 	int num_devices = p->n_pdds;
4115 	struct svm_range_list *svms;
4116 	struct svm_range *prange;
4117 	uint32_t count = 0;
4118 
4119 	*svm_priv_data_size = 0;
4120 
4121 	svms = &p->svms;
4122 
4123 	mutex_lock(&svms->lock);
4124 	list_for_each_entry(prange, &svms->list, list) {
4125 		pr_debug("prange: 0x%p start: 0x%lx\t npages: 0x%llx\t end: 0x%llx\n",
4126 			 prange, prange->start, prange->npages,
4127 			 prange->start + prange->npages - 1);
4128 		count++;
4129 	}
4130 	mutex_unlock(&svms->lock);
4131 
4132 	*num_svm_ranges = count;
4133 	/* Only the accessbility attributes need to be queried for all the gpus
4134 	 * individually, remaining ones are spanned across the entire process
4135 	 * regardless of the various gpu nodes. Of the remaining attributes,
4136 	 * KFD_IOCTL_SVM_ATTR_CLR_FLAGS need not be saved.
4137 	 *
4138 	 * KFD_IOCTL_SVM_ATTR_PREFERRED_LOC
4139 	 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC
4140 	 * KFD_IOCTL_SVM_ATTR_SET_FLAGS
4141 	 * KFD_IOCTL_SVM_ATTR_GRANULARITY
4142 	 *
4143 	 * ** ACCESSBILITY ATTRIBUTES **
4144 	 * (Considered as one, type is altered during query, value is gpuid)
4145 	 * KFD_IOCTL_SVM_ATTR_ACCESS
4146 	 * KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE
4147 	 * KFD_IOCTL_SVM_ATTR_NO_ACCESS
4148 	 */
4149 	if (*num_svm_ranges > 0) {
4150 		common_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4151 			nattr_common;
4152 		accessibility_size = sizeof(struct kfd_ioctl_svm_attribute) *
4153 			nattr_accessibility * num_devices;
4154 
4155 		total_size = sizeof(struct kfd_criu_svm_range_priv_data) +
4156 			common_attr_size + accessibility_size;
4157 
4158 		*svm_priv_data_size = *num_svm_ranges * total_size;
4159 	}
4160 
4161 	pr_debug("num_svm_ranges %u total_priv_size %llu\n", *num_svm_ranges,
4162 		 *svm_priv_data_size);
4163 }
4164 
4165 int kfd_criu_checkpoint_svm(struct kfd_process *p,
4166 			    uint8_t __user *user_priv_data,
4167 			    uint64_t *priv_data_offset)
4168 {
4169 	struct kfd_criu_svm_range_priv_data *svm_priv = NULL;
4170 	struct kfd_ioctl_svm_attribute *query_attr = NULL;
4171 	uint64_t svm_priv_data_size, query_attr_size = 0;
4172 	int index, nattr_common = 4, ret = 0;
4173 	struct svm_range_list *svms;
4174 	int num_devices = p->n_pdds;
4175 	struct svm_range *prange;
4176 	struct mm_struct *mm;
4177 
4178 	svms = &p->svms;
4179 
4180 	mm = get_task_mm(p->lead_thread);
4181 	if (!mm) {
4182 		pr_err("failed to get mm for the target process\n");
4183 		return -ESRCH;
4184 	}
4185 
4186 	query_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4187 				(nattr_common + num_devices);
4188 
4189 	query_attr = kzalloc(query_attr_size, GFP_KERNEL);
4190 	if (!query_attr) {
4191 		ret = -ENOMEM;
4192 		goto exit;
4193 	}
4194 
4195 	query_attr[0].type = KFD_IOCTL_SVM_ATTR_PREFERRED_LOC;
4196 	query_attr[1].type = KFD_IOCTL_SVM_ATTR_PREFETCH_LOC;
4197 	query_attr[2].type = KFD_IOCTL_SVM_ATTR_SET_FLAGS;
4198 	query_attr[3].type = KFD_IOCTL_SVM_ATTR_GRANULARITY;
4199 
4200 	for (index = 0; index < num_devices; index++) {
4201 		struct kfd_process_device *pdd = p->pdds[index];
4202 
4203 		query_attr[index + nattr_common].type =
4204 			KFD_IOCTL_SVM_ATTR_ACCESS;
4205 		query_attr[index + nattr_common].value = pdd->user_gpu_id;
4206 	}
4207 
4208 	svm_priv_data_size = sizeof(*svm_priv) + query_attr_size;
4209 
4210 	svm_priv = kzalloc(svm_priv_data_size, GFP_KERNEL);
4211 	if (!svm_priv) {
4212 		ret = -ENOMEM;
4213 		goto exit_query;
4214 	}
4215 
4216 	index = 0;
4217 	list_for_each_entry(prange, &svms->list, list) {
4218 
4219 		svm_priv->object_type = KFD_CRIU_OBJECT_TYPE_SVM_RANGE;
4220 		svm_priv->start_addr = prange->start;
4221 		svm_priv->size = prange->npages;
4222 		memcpy(&svm_priv->attrs, query_attr, query_attr_size);
4223 		pr_debug("CRIU: prange: 0x%p start: 0x%lx\t npages: 0x%llx end: 0x%llx\t size: 0x%llx\n",
4224 			 prange, prange->start, prange->npages,
4225 			 prange->start + prange->npages - 1,
4226 			 prange->npages * PAGE_SIZE);
4227 
4228 		ret = svm_range_get_attr(p, mm, svm_priv->start_addr,
4229 					 svm_priv->size,
4230 					 (nattr_common + num_devices),
4231 					 svm_priv->attrs);
4232 		if (ret) {
4233 			pr_err("CRIU: failed to obtain range attributes\n");
4234 			goto exit_priv;
4235 		}
4236 
4237 		if (copy_to_user(user_priv_data + *priv_data_offset, svm_priv,
4238 				 svm_priv_data_size)) {
4239 			pr_err("Failed to copy svm priv to user\n");
4240 			ret = -EFAULT;
4241 			goto exit_priv;
4242 		}
4243 
4244 		*priv_data_offset += svm_priv_data_size;
4245 
4246 	}
4247 
4248 
4249 exit_priv:
4250 	kfree(svm_priv);
4251 exit_query:
4252 	kfree(query_attr);
4253 exit:
4254 	mmput(mm);
4255 	return ret;
4256 }
4257 
4258 int
4259 svm_ioctl(struct kfd_process *p, enum kfd_ioctl_svm_op op, uint64_t start,
4260 	  uint64_t size, uint32_t nattrs, struct kfd_ioctl_svm_attribute *attrs)
4261 {
4262 	struct mm_struct *mm = current->mm;
4263 	int r;
4264 
4265 	start >>= PAGE_SHIFT;
4266 	size >>= PAGE_SHIFT;
4267 
4268 	switch (op) {
4269 	case KFD_IOCTL_SVM_OP_SET_ATTR:
4270 		r = svm_range_set_attr(p, mm, start, size, nattrs, attrs);
4271 		break;
4272 	case KFD_IOCTL_SVM_OP_GET_ATTR:
4273 		r = svm_range_get_attr(p, mm, start, size, nattrs, attrs);
4274 		break;
4275 	default:
4276 		r = -EINVAL;
4277 		break;
4278 	}
4279 
4280 	return r;
4281 }
4282