xref: /linux-6.15/drivers/gpu/drm/amd/amdkfd/kfd_svm.c (revision 78964fca)
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, uint64_t *vram_pages)
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 	uint64_t vram_pages_dev;
168 	int i, r;
169 
170 	if (!addr) {
171 		addr = kvcalloc(prange->npages, sizeof(*addr), GFP_KERNEL);
172 		if (!addr)
173 			return -ENOMEM;
174 		prange->dma_addr[gpuidx] = addr;
175 	}
176 
177 	vram_pages_dev = 0;
178 	addr += offset;
179 	for (i = 0; i < npages; i++) {
180 		if (svm_is_valid_dma_mapping_addr(dev, addr[i]))
181 			dma_unmap_page(dev, addr[i], PAGE_SIZE, dir);
182 
183 		page = hmm_pfn_to_page(hmm_pfns[i]);
184 		if (is_zone_device_page(page)) {
185 			struct amdgpu_device *bo_adev = prange->svm_bo->node->adev;
186 
187 			vram_pages_dev++;
188 			addr[i] = (hmm_pfns[i] << PAGE_SHIFT) +
189 				   bo_adev->vm_manager.vram_base_offset -
190 				   bo_adev->kfd.pgmap.range.start;
191 			addr[i] |= SVM_RANGE_VRAM_DOMAIN;
192 			pr_debug_ratelimited("vram address: 0x%llx\n", addr[i]);
193 			continue;
194 		}
195 		addr[i] = dma_map_page(dev, page, 0, PAGE_SIZE, dir);
196 		r = dma_mapping_error(dev, addr[i]);
197 		if (r) {
198 			dev_err(dev, "failed %d dma_map_page\n", r);
199 			return r;
200 		}
201 		pr_debug_ratelimited("dma mapping 0x%llx for page addr 0x%lx\n",
202 				     addr[i] >> PAGE_SHIFT, page_to_pfn(page));
203 	}
204 	*vram_pages = vram_pages_dev;
205 	return 0;
206 }
207 
208 static int
209 svm_range_dma_map(struct svm_range *prange, unsigned long *bitmap,
210 		  unsigned long offset, unsigned long npages,
211 		  unsigned long *hmm_pfns, uint64_t *vram_pages)
212 {
213 	struct kfd_process *p;
214 	uint32_t gpuidx;
215 	int r;
216 
217 	p = container_of(prange->svms, struct kfd_process, svms);
218 
219 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
220 		struct kfd_process_device *pdd;
221 
222 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
223 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
224 		if (!pdd) {
225 			pr_debug("failed to find device idx %d\n", gpuidx);
226 			return -EINVAL;
227 		}
228 
229 		r = svm_range_dma_map_dev(pdd->dev->adev, prange, offset, npages,
230 					  hmm_pfns, gpuidx, vram_pages);
231 		if (r)
232 			break;
233 	}
234 
235 	return r;
236 }
237 
238 void svm_range_dma_unmap_dev(struct device *dev, dma_addr_t *dma_addr,
239 			 unsigned long offset, unsigned long npages)
240 {
241 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
242 	int i;
243 
244 	if (!dma_addr)
245 		return;
246 
247 	for (i = offset; i < offset + npages; i++) {
248 		if (!svm_is_valid_dma_mapping_addr(dev, dma_addr[i]))
249 			continue;
250 		pr_debug_ratelimited("unmap 0x%llx\n", dma_addr[i] >> PAGE_SHIFT);
251 		dma_unmap_page(dev, dma_addr[i], PAGE_SIZE, dir);
252 		dma_addr[i] = 0;
253 	}
254 }
255 
256 void svm_range_dma_unmap(struct svm_range *prange)
257 {
258 	struct kfd_process_device *pdd;
259 	dma_addr_t *dma_addr;
260 	struct device *dev;
261 	struct kfd_process *p;
262 	uint32_t gpuidx;
263 
264 	p = container_of(prange->svms, struct kfd_process, svms);
265 
266 	for (gpuidx = 0; gpuidx < MAX_GPU_INSTANCE; gpuidx++) {
267 		dma_addr = prange->dma_addr[gpuidx];
268 		if (!dma_addr)
269 			continue;
270 
271 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
272 		if (!pdd) {
273 			pr_debug("failed to find device idx %d\n", gpuidx);
274 			continue;
275 		}
276 		dev = &pdd->dev->adev->pdev->dev;
277 
278 		svm_range_dma_unmap_dev(dev, dma_addr, 0, prange->npages);
279 	}
280 }
281 
282 static void svm_range_free(struct svm_range *prange, bool do_unmap)
283 {
284 	uint64_t size = (prange->last - prange->start + 1) << PAGE_SHIFT;
285 	struct kfd_process *p = container_of(prange->svms, struct kfd_process, svms);
286 	uint32_t gpuidx;
287 
288 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms, prange,
289 		 prange->start, prange->last);
290 
291 	svm_range_vram_node_free(prange);
292 	if (do_unmap)
293 		svm_range_dma_unmap(prange);
294 
295 	if (do_unmap && !p->xnack_enabled) {
296 		pr_debug("unreserve prange 0x%p size: 0x%llx\n", prange, size);
297 		amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
298 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
299 	}
300 
301 	/* free dma_addr array for each gpu */
302 	for (gpuidx = 0; gpuidx < MAX_GPU_INSTANCE; gpuidx++) {
303 		if (prange->dma_addr[gpuidx]) {
304 			kvfree(prange->dma_addr[gpuidx]);
305 			prange->dma_addr[gpuidx] = NULL;
306 		}
307 	}
308 
309 	mutex_destroy(&prange->lock);
310 	mutex_destroy(&prange->migrate_mutex);
311 	kfree(prange);
312 }
313 
314 static void
315 svm_range_set_default_attributes(int32_t *location, int32_t *prefetch_loc,
316 				 uint8_t *granularity, uint32_t *flags)
317 {
318 	*location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
319 	*prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
320 	*granularity = 9;
321 	*flags =
322 		KFD_IOCTL_SVM_FLAG_HOST_ACCESS | KFD_IOCTL_SVM_FLAG_COHERENT;
323 }
324 
325 static struct
326 svm_range *svm_range_new(struct svm_range_list *svms, uint64_t start,
327 			 uint64_t last, bool update_mem_usage)
328 {
329 	uint64_t size = last - start + 1;
330 	struct svm_range *prange;
331 	struct kfd_process *p;
332 
333 	prange = kzalloc(sizeof(*prange), GFP_KERNEL);
334 	if (!prange)
335 		return NULL;
336 
337 	p = container_of(svms, struct kfd_process, svms);
338 	if (!p->xnack_enabled && update_mem_usage &&
339 	    amdgpu_amdkfd_reserve_mem_limit(NULL, size << PAGE_SHIFT,
340 				    KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0)) {
341 		pr_info("SVM mapping failed, exceeds resident system memory limit\n");
342 		kfree(prange);
343 		return NULL;
344 	}
345 	prange->npages = size;
346 	prange->svms = svms;
347 	prange->start = start;
348 	prange->last = last;
349 	INIT_LIST_HEAD(&prange->list);
350 	INIT_LIST_HEAD(&prange->update_list);
351 	INIT_LIST_HEAD(&prange->svm_bo_list);
352 	INIT_LIST_HEAD(&prange->deferred_list);
353 	INIT_LIST_HEAD(&prange->child_list);
354 	atomic_set(&prange->invalid, 0);
355 	prange->validate_timestamp = 0;
356 	prange->vram_pages = 0;
357 	mutex_init(&prange->migrate_mutex);
358 	mutex_init(&prange->lock);
359 
360 	if (p->xnack_enabled)
361 		bitmap_copy(prange->bitmap_access, svms->bitmap_supported,
362 			    MAX_GPU_INSTANCE);
363 
364 	svm_range_set_default_attributes(&prange->preferred_loc,
365 					 &prange->prefetch_loc,
366 					 &prange->granularity, &prange->flags);
367 
368 	pr_debug("svms 0x%p [0x%llx 0x%llx]\n", svms, start, last);
369 
370 	return prange;
371 }
372 
373 static bool svm_bo_ref_unless_zero(struct svm_range_bo *svm_bo)
374 {
375 	if (!svm_bo || !kref_get_unless_zero(&svm_bo->kref))
376 		return false;
377 
378 	return true;
379 }
380 
381 static void svm_range_bo_release(struct kref *kref)
382 {
383 	struct svm_range_bo *svm_bo;
384 
385 	svm_bo = container_of(kref, struct svm_range_bo, kref);
386 	pr_debug("svm_bo 0x%p\n", svm_bo);
387 
388 	spin_lock(&svm_bo->list_lock);
389 	while (!list_empty(&svm_bo->range_list)) {
390 		struct svm_range *prange =
391 				list_first_entry(&svm_bo->range_list,
392 						struct svm_range, svm_bo_list);
393 		/* list_del_init tells a concurrent svm_range_vram_node_new when
394 		 * it's safe to reuse the svm_bo pointer and svm_bo_list head.
395 		 */
396 		list_del_init(&prange->svm_bo_list);
397 		spin_unlock(&svm_bo->list_lock);
398 
399 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
400 			 prange->start, prange->last);
401 		mutex_lock(&prange->lock);
402 		prange->svm_bo = NULL;
403 		/* prange should not hold vram page now */
404 		WARN_ON(prange->actual_loc);
405 		mutex_unlock(&prange->lock);
406 
407 		spin_lock(&svm_bo->list_lock);
408 	}
409 	spin_unlock(&svm_bo->list_lock);
410 	if (!dma_fence_is_signaled(&svm_bo->eviction_fence->base)) {
411 		/* We're not in the eviction worker.
412 		 * Signal the fence and synchronize with any
413 		 * pending eviction work.
414 		 */
415 		dma_fence_signal(&svm_bo->eviction_fence->base);
416 		cancel_work_sync(&svm_bo->eviction_work);
417 	}
418 	dma_fence_put(&svm_bo->eviction_fence->base);
419 	amdgpu_bo_unref(&svm_bo->bo);
420 	kfree(svm_bo);
421 }
422 
423 static void svm_range_bo_wq_release(struct work_struct *work)
424 {
425 	struct svm_range_bo *svm_bo;
426 
427 	svm_bo = container_of(work, struct svm_range_bo, release_work);
428 	svm_range_bo_release(&svm_bo->kref);
429 }
430 
431 static void svm_range_bo_release_async(struct kref *kref)
432 {
433 	struct svm_range_bo *svm_bo;
434 
435 	svm_bo = container_of(kref, struct svm_range_bo, kref);
436 	pr_debug("svm_bo 0x%p\n", svm_bo);
437 	INIT_WORK(&svm_bo->release_work, svm_range_bo_wq_release);
438 	schedule_work(&svm_bo->release_work);
439 }
440 
441 void svm_range_bo_unref_async(struct svm_range_bo *svm_bo)
442 {
443 	kref_put(&svm_bo->kref, svm_range_bo_release_async);
444 }
445 
446 static void svm_range_bo_unref(struct svm_range_bo *svm_bo)
447 {
448 	if (svm_bo)
449 		kref_put(&svm_bo->kref, svm_range_bo_release);
450 }
451 
452 static bool
453 svm_range_validate_svm_bo(struct kfd_node *node, struct svm_range *prange)
454 {
455 	mutex_lock(&prange->lock);
456 	if (!prange->svm_bo) {
457 		mutex_unlock(&prange->lock);
458 		return false;
459 	}
460 	if (prange->ttm_res) {
461 		/* We still have a reference, all is well */
462 		mutex_unlock(&prange->lock);
463 		return true;
464 	}
465 	if (svm_bo_ref_unless_zero(prange->svm_bo)) {
466 		/*
467 		 * Migrate from GPU to GPU, remove range from source svm_bo->node
468 		 * range list, and return false to allocate svm_bo from destination
469 		 * node.
470 		 */
471 		if (prange->svm_bo->node != node) {
472 			mutex_unlock(&prange->lock);
473 
474 			spin_lock(&prange->svm_bo->list_lock);
475 			list_del_init(&prange->svm_bo_list);
476 			spin_unlock(&prange->svm_bo->list_lock);
477 
478 			svm_range_bo_unref(prange->svm_bo);
479 			return false;
480 		}
481 		if (READ_ONCE(prange->svm_bo->evicting)) {
482 			struct dma_fence *f;
483 			struct svm_range_bo *svm_bo;
484 			/* The BO is getting evicted,
485 			 * we need to get a new one
486 			 */
487 			mutex_unlock(&prange->lock);
488 			svm_bo = prange->svm_bo;
489 			f = dma_fence_get(&svm_bo->eviction_fence->base);
490 			svm_range_bo_unref(prange->svm_bo);
491 			/* wait for the fence to avoid long spin-loop
492 			 * at list_empty_careful
493 			 */
494 			dma_fence_wait(f, false);
495 			dma_fence_put(f);
496 		} else {
497 			/* The BO was still around and we got
498 			 * a new reference to it
499 			 */
500 			mutex_unlock(&prange->lock);
501 			pr_debug("reuse old bo svms 0x%p [0x%lx 0x%lx]\n",
502 				 prange->svms, prange->start, prange->last);
503 
504 			prange->ttm_res = prange->svm_bo->bo->tbo.resource;
505 			return true;
506 		}
507 
508 	} else {
509 		mutex_unlock(&prange->lock);
510 	}
511 
512 	/* We need a new svm_bo. Spin-loop to wait for concurrent
513 	 * svm_range_bo_release to finish removing this range from
514 	 * its range list and set prange->svm_bo to null. After this,
515 	 * it is safe to reuse the svm_bo pointer and svm_bo_list head.
516 	 */
517 	while (!list_empty_careful(&prange->svm_bo_list) || prange->svm_bo)
518 		cond_resched();
519 
520 	return false;
521 }
522 
523 static struct svm_range_bo *svm_range_bo_new(void)
524 {
525 	struct svm_range_bo *svm_bo;
526 
527 	svm_bo = kzalloc(sizeof(*svm_bo), GFP_KERNEL);
528 	if (!svm_bo)
529 		return NULL;
530 
531 	kref_init(&svm_bo->kref);
532 	INIT_LIST_HEAD(&svm_bo->range_list);
533 	spin_lock_init(&svm_bo->list_lock);
534 
535 	return svm_bo;
536 }
537 
538 int
539 svm_range_vram_node_new(struct kfd_node *node, struct svm_range *prange,
540 			bool clear)
541 {
542 	struct amdgpu_bo_param bp;
543 	struct svm_range_bo *svm_bo;
544 	struct amdgpu_bo_user *ubo;
545 	struct amdgpu_bo *bo;
546 	struct kfd_process *p;
547 	struct mm_struct *mm;
548 	int r;
549 
550 	p = container_of(prange->svms, struct kfd_process, svms);
551 	pr_debug("pasid: %x svms 0x%p [0x%lx 0x%lx]\n", p->pasid, prange->svms,
552 		 prange->start, prange->last);
553 
554 	if (svm_range_validate_svm_bo(node, prange))
555 		return 0;
556 
557 	svm_bo = svm_range_bo_new();
558 	if (!svm_bo) {
559 		pr_debug("failed to alloc svm bo\n");
560 		return -ENOMEM;
561 	}
562 	mm = get_task_mm(p->lead_thread);
563 	if (!mm) {
564 		pr_debug("failed to get mm\n");
565 		kfree(svm_bo);
566 		return -ESRCH;
567 	}
568 	svm_bo->node = node;
569 	svm_bo->eviction_fence =
570 		amdgpu_amdkfd_fence_create(dma_fence_context_alloc(1),
571 					   mm,
572 					   svm_bo);
573 	mmput(mm);
574 	INIT_WORK(&svm_bo->eviction_work, svm_range_evict_svm_bo_worker);
575 	svm_bo->evicting = 0;
576 	memset(&bp, 0, sizeof(bp));
577 	bp.size = prange->npages * PAGE_SIZE;
578 	bp.byte_align = PAGE_SIZE;
579 	bp.domain = AMDGPU_GEM_DOMAIN_VRAM;
580 	bp.flags = AMDGPU_GEM_CREATE_NO_CPU_ACCESS;
581 	bp.flags |= clear ? AMDGPU_GEM_CREATE_VRAM_CLEARED : 0;
582 	bp.flags |= AMDGPU_GEM_CREATE_DISCARDABLE;
583 	bp.type = ttm_bo_type_device;
584 	bp.resv = NULL;
585 	if (node->xcp)
586 		bp.xcp_id_plus1 = node->xcp->id + 1;
587 
588 	r = amdgpu_bo_create_user(node->adev, &bp, &ubo);
589 	if (r) {
590 		pr_debug("failed %d to create bo\n", r);
591 		goto create_bo_failed;
592 	}
593 	bo = &ubo->bo;
594 
595 	pr_debug("alloc bo at offset 0x%lx size 0x%lx on partition %d\n",
596 		 bo->tbo.resource->start << PAGE_SHIFT, bp.size,
597 		 bp.xcp_id_plus1 - 1);
598 
599 	r = amdgpu_bo_reserve(bo, true);
600 	if (r) {
601 		pr_debug("failed %d to reserve bo\n", r);
602 		goto reserve_bo_failed;
603 	}
604 
605 	if (clear) {
606 		r = amdgpu_bo_sync_wait(bo, AMDGPU_FENCE_OWNER_KFD, false);
607 		if (r) {
608 			pr_debug("failed %d to sync bo\n", r);
609 			amdgpu_bo_unreserve(bo);
610 			goto reserve_bo_failed;
611 		}
612 	}
613 
614 	r = dma_resv_reserve_fences(bo->tbo.base.resv, 1);
615 	if (r) {
616 		pr_debug("failed %d to reserve bo\n", r);
617 		amdgpu_bo_unreserve(bo);
618 		goto reserve_bo_failed;
619 	}
620 	amdgpu_bo_fence(bo, &svm_bo->eviction_fence->base, true);
621 
622 	amdgpu_bo_unreserve(bo);
623 
624 	svm_bo->bo = bo;
625 	prange->svm_bo = svm_bo;
626 	prange->ttm_res = bo->tbo.resource;
627 	prange->offset = 0;
628 
629 	spin_lock(&svm_bo->list_lock);
630 	list_add(&prange->svm_bo_list, &svm_bo->range_list);
631 	spin_unlock(&svm_bo->list_lock);
632 
633 	return 0;
634 
635 reserve_bo_failed:
636 	amdgpu_bo_unref(&bo);
637 create_bo_failed:
638 	dma_fence_put(&svm_bo->eviction_fence->base);
639 	kfree(svm_bo);
640 	prange->ttm_res = NULL;
641 
642 	return r;
643 }
644 
645 void svm_range_vram_node_free(struct svm_range *prange)
646 {
647 	/* serialize prange->svm_bo unref */
648 	mutex_lock(&prange->lock);
649 	/* prange->svm_bo has not been unref */
650 	if (prange->ttm_res) {
651 		prange->ttm_res = NULL;
652 		mutex_unlock(&prange->lock);
653 		svm_range_bo_unref(prange->svm_bo);
654 	} else
655 		mutex_unlock(&prange->lock);
656 }
657 
658 struct kfd_node *
659 svm_range_get_node_by_id(struct svm_range *prange, uint32_t gpu_id)
660 {
661 	struct kfd_process *p;
662 	struct kfd_process_device *pdd;
663 
664 	p = container_of(prange->svms, struct kfd_process, svms);
665 	pdd = kfd_process_device_data_by_id(p, gpu_id);
666 	if (!pdd) {
667 		pr_debug("failed to get kfd process device by id 0x%x\n", gpu_id);
668 		return NULL;
669 	}
670 
671 	return pdd->dev;
672 }
673 
674 struct kfd_process_device *
675 svm_range_get_pdd_by_node(struct svm_range *prange, struct kfd_node *node)
676 {
677 	struct kfd_process *p;
678 
679 	p = container_of(prange->svms, struct kfd_process, svms);
680 
681 	return kfd_get_process_device_data(node, p);
682 }
683 
684 static int svm_range_bo_validate(void *param, struct amdgpu_bo *bo)
685 {
686 	struct ttm_operation_ctx ctx = { false, false };
687 
688 	amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_VRAM);
689 
690 	return ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
691 }
692 
693 static int
694 svm_range_check_attr(struct kfd_process *p,
695 		     uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
696 {
697 	uint32_t i;
698 
699 	for (i = 0; i < nattr; i++) {
700 		uint32_t val = attrs[i].value;
701 		int gpuidx = MAX_GPU_INSTANCE;
702 
703 		switch (attrs[i].type) {
704 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
705 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM &&
706 			    val != KFD_IOCTL_SVM_LOCATION_UNDEFINED)
707 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
708 			break;
709 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
710 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM)
711 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
712 			break;
713 		case KFD_IOCTL_SVM_ATTR_ACCESS:
714 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
715 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
716 			gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
717 			break;
718 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
719 			break;
720 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
721 			break;
722 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
723 			break;
724 		default:
725 			pr_debug("unknown attr type 0x%x\n", attrs[i].type);
726 			return -EINVAL;
727 		}
728 
729 		if (gpuidx < 0) {
730 			pr_debug("no GPU 0x%x found\n", val);
731 			return -EINVAL;
732 		} else if (gpuidx < MAX_GPU_INSTANCE &&
733 			   !test_bit(gpuidx, p->svms.bitmap_supported)) {
734 			pr_debug("GPU 0x%x not supported\n", val);
735 			return -EINVAL;
736 		}
737 	}
738 
739 	return 0;
740 }
741 
742 static void
743 svm_range_apply_attrs(struct kfd_process *p, struct svm_range *prange,
744 		      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
745 		      bool *update_mapping)
746 {
747 	uint32_t i;
748 	int gpuidx;
749 
750 	for (i = 0; i < nattr; i++) {
751 		switch (attrs[i].type) {
752 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
753 			prange->preferred_loc = attrs[i].value;
754 			break;
755 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
756 			prange->prefetch_loc = attrs[i].value;
757 			break;
758 		case KFD_IOCTL_SVM_ATTR_ACCESS:
759 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
760 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
761 			if (!p->xnack_enabled)
762 				*update_mapping = true;
763 
764 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
765 							       attrs[i].value);
766 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
767 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
768 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
769 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
770 				bitmap_set(prange->bitmap_access, gpuidx, 1);
771 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
772 			} else {
773 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
774 				bitmap_set(prange->bitmap_aip, gpuidx, 1);
775 			}
776 			break;
777 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
778 			*update_mapping = true;
779 			prange->flags |= attrs[i].value;
780 			break;
781 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
782 			*update_mapping = true;
783 			prange->flags &= ~attrs[i].value;
784 			break;
785 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
786 			prange->granularity = min_t(uint32_t, attrs[i].value, 0x3F);
787 			break;
788 		default:
789 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
790 		}
791 	}
792 }
793 
794 static bool
795 svm_range_is_same_attrs(struct kfd_process *p, struct svm_range *prange,
796 			uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
797 {
798 	uint32_t i;
799 	int gpuidx;
800 
801 	for (i = 0; i < nattr; i++) {
802 		switch (attrs[i].type) {
803 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
804 			if (prange->preferred_loc != attrs[i].value)
805 				return false;
806 			break;
807 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
808 			/* Prefetch should always trigger a migration even
809 			 * if the value of the attribute didn't change.
810 			 */
811 			return false;
812 		case KFD_IOCTL_SVM_ATTR_ACCESS:
813 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
814 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
815 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
816 							       attrs[i].value);
817 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
818 				if (test_bit(gpuidx, prange->bitmap_access) ||
819 				    test_bit(gpuidx, prange->bitmap_aip))
820 					return false;
821 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
822 				if (!test_bit(gpuidx, prange->bitmap_access))
823 					return false;
824 			} else {
825 				if (!test_bit(gpuidx, prange->bitmap_aip))
826 					return false;
827 			}
828 			break;
829 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
830 			if ((prange->flags & attrs[i].value) != attrs[i].value)
831 				return false;
832 			break;
833 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
834 			if ((prange->flags & attrs[i].value) != 0)
835 				return false;
836 			break;
837 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
838 			if (prange->granularity != attrs[i].value)
839 				return false;
840 			break;
841 		default:
842 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
843 		}
844 	}
845 
846 	return true;
847 }
848 
849 /**
850  * svm_range_debug_dump - print all range information from svms
851  * @svms: svm range list header
852  *
853  * debug output svm range start, end, prefetch location from svms
854  * interval tree and link list
855  *
856  * Context: The caller must hold svms->lock
857  */
858 static void svm_range_debug_dump(struct svm_range_list *svms)
859 {
860 	struct interval_tree_node *node;
861 	struct svm_range *prange;
862 
863 	pr_debug("dump svms 0x%p list\n", svms);
864 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
865 
866 	list_for_each_entry(prange, &svms->list, list) {
867 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
868 			 prange, prange->start, prange->npages,
869 			 prange->start + prange->npages - 1,
870 			 prange->actual_loc);
871 	}
872 
873 	pr_debug("dump svms 0x%p interval tree\n", svms);
874 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
875 	node = interval_tree_iter_first(&svms->objects, 0, ~0ULL);
876 	while (node) {
877 		prange = container_of(node, struct svm_range, it_node);
878 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
879 			 prange, prange->start, prange->npages,
880 			 prange->start + prange->npages - 1,
881 			 prange->actual_loc);
882 		node = interval_tree_iter_next(node, 0, ~0ULL);
883 	}
884 }
885 
886 static void *
887 svm_range_copy_array(void *psrc, size_t size, uint64_t num_elements,
888 		     uint64_t offset)
889 {
890 	unsigned char *dst;
891 
892 	dst = kvmalloc_array(num_elements, size, GFP_KERNEL);
893 	if (!dst)
894 		return NULL;
895 	memcpy(dst, (unsigned char *)psrc + offset, num_elements * size);
896 
897 	return (void *)dst;
898 }
899 
900 static int
901 svm_range_copy_dma_addrs(struct svm_range *dst, struct svm_range *src)
902 {
903 	int i;
904 
905 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
906 		if (!src->dma_addr[i])
907 			continue;
908 		dst->dma_addr[i] = svm_range_copy_array(src->dma_addr[i],
909 					sizeof(*src->dma_addr[i]), src->npages, 0);
910 		if (!dst->dma_addr[i])
911 			return -ENOMEM;
912 	}
913 
914 	return 0;
915 }
916 
917 static int
918 svm_range_split_array(void *ppnew, void *ppold, size_t size,
919 		      uint64_t old_start, uint64_t old_n,
920 		      uint64_t new_start, uint64_t new_n)
921 {
922 	unsigned char *new, *old, *pold;
923 	uint64_t d;
924 
925 	if (!ppold)
926 		return 0;
927 	pold = *(unsigned char **)ppold;
928 	if (!pold)
929 		return 0;
930 
931 	d = (new_start - old_start) * size;
932 	new = svm_range_copy_array(pold, size, new_n, d);
933 	if (!new)
934 		return -ENOMEM;
935 	d = (new_start == old_start) ? new_n * size : 0;
936 	old = svm_range_copy_array(pold, size, old_n, d);
937 	if (!old) {
938 		kvfree(new);
939 		return -ENOMEM;
940 	}
941 	kvfree(pold);
942 	*(void **)ppold = old;
943 	*(void **)ppnew = new;
944 
945 	return 0;
946 }
947 
948 static int
949 svm_range_split_pages(struct svm_range *new, struct svm_range *old,
950 		      uint64_t start, uint64_t last)
951 {
952 	uint64_t npages = last - start + 1;
953 	int i, r;
954 
955 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
956 		r = svm_range_split_array(&new->dma_addr[i], &old->dma_addr[i],
957 					  sizeof(*old->dma_addr[i]), old->start,
958 					  npages, new->start, new->npages);
959 		if (r)
960 			return r;
961 	}
962 
963 	return 0;
964 }
965 
966 static int
967 svm_range_split_nodes(struct svm_range *new, struct svm_range *old,
968 		      uint64_t start, uint64_t last)
969 {
970 	uint64_t npages = last - start + 1;
971 
972 	pr_debug("svms 0x%p new prange 0x%p start 0x%lx [0x%llx 0x%llx]\n",
973 		 new->svms, new, new->start, start, last);
974 
975 	if (new->start == old->start) {
976 		new->offset = old->offset;
977 		old->offset += new->npages;
978 	} else {
979 		new->offset = old->offset + npages;
980 	}
981 
982 	new->svm_bo = svm_range_bo_ref(old->svm_bo);
983 	new->ttm_res = old->ttm_res;
984 
985 	/* set new's vram_pages as old range's now, the acurate vram_pages
986 	 * will be updated during mapping
987 	 */
988 	new->vram_pages = min(old->vram_pages, new->npages);
989 
990 	spin_lock(&new->svm_bo->list_lock);
991 	list_add(&new->svm_bo_list, &new->svm_bo->range_list);
992 	spin_unlock(&new->svm_bo->list_lock);
993 
994 	return 0;
995 }
996 
997 /**
998  * svm_range_split_adjust - split range and adjust
999  *
1000  * @new: new range
1001  * @old: the old range
1002  * @start: the old range adjust to start address in pages
1003  * @last: the old range adjust to last address in pages
1004  *
1005  * Copy system memory dma_addr or vram ttm_res in old range to new
1006  * range from new_start up to size new->npages, the remaining old range is from
1007  * start to last
1008  *
1009  * Return:
1010  * 0 - OK, -ENOMEM - out of memory
1011  */
1012 static int
1013 svm_range_split_adjust(struct svm_range *new, struct svm_range *old,
1014 		      uint64_t start, uint64_t last)
1015 {
1016 	int r;
1017 
1018 	pr_debug("svms 0x%p new 0x%lx old [0x%lx 0x%lx] => [0x%llx 0x%llx]\n",
1019 		 new->svms, new->start, old->start, old->last, start, last);
1020 
1021 	if (new->start < old->start ||
1022 	    new->last > old->last) {
1023 		WARN_ONCE(1, "invalid new range start or last\n");
1024 		return -EINVAL;
1025 	}
1026 
1027 	r = svm_range_split_pages(new, old, start, last);
1028 	if (r)
1029 		return r;
1030 
1031 	if (old->actual_loc && old->ttm_res) {
1032 		r = svm_range_split_nodes(new, old, start, last);
1033 		if (r)
1034 			return r;
1035 	}
1036 
1037 	old->npages = last - start + 1;
1038 	old->start = start;
1039 	old->last = last;
1040 	new->flags = old->flags;
1041 	new->preferred_loc = old->preferred_loc;
1042 	new->prefetch_loc = old->prefetch_loc;
1043 	new->actual_loc = old->actual_loc;
1044 	new->granularity = old->granularity;
1045 	new->mapped_to_gpu = old->mapped_to_gpu;
1046 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
1047 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
1048 
1049 	return 0;
1050 }
1051 
1052 /**
1053  * svm_range_split - split a range in 2 ranges
1054  *
1055  * @prange: the svm range to split
1056  * @start: the remaining range start address in pages
1057  * @last: the remaining range last address in pages
1058  * @new: the result new range generated
1059  *
1060  * Two cases only:
1061  * case 1: if start == prange->start
1062  *         prange ==> prange[start, last]
1063  *         new range [last + 1, prange->last]
1064  *
1065  * case 2: if last == prange->last
1066  *         prange ==> prange[start, last]
1067  *         new range [prange->start, start - 1]
1068  *
1069  * Return:
1070  * 0 - OK, -ENOMEM - out of memory, -EINVAL - invalid start, last
1071  */
1072 static int
1073 svm_range_split(struct svm_range *prange, uint64_t start, uint64_t last,
1074 		struct svm_range **new)
1075 {
1076 	uint64_t old_start = prange->start;
1077 	uint64_t old_last = prange->last;
1078 	struct svm_range_list *svms;
1079 	int r = 0;
1080 
1081 	pr_debug("svms 0x%p [0x%llx 0x%llx] to [0x%llx 0x%llx]\n", prange->svms,
1082 		 old_start, old_last, start, last);
1083 
1084 	if (old_start != start && old_last != last)
1085 		return -EINVAL;
1086 	if (start < old_start || last > old_last)
1087 		return -EINVAL;
1088 
1089 	svms = prange->svms;
1090 	if (old_start == start)
1091 		*new = svm_range_new(svms, last + 1, old_last, false);
1092 	else
1093 		*new = svm_range_new(svms, old_start, start - 1, false);
1094 	if (!*new)
1095 		return -ENOMEM;
1096 
1097 	r = svm_range_split_adjust(*new, prange, start, last);
1098 	if (r) {
1099 		pr_debug("failed %d split [0x%llx 0x%llx] to [0x%llx 0x%llx]\n",
1100 			 r, old_start, old_last, start, last);
1101 		svm_range_free(*new, false);
1102 		*new = NULL;
1103 	}
1104 
1105 	return r;
1106 }
1107 
1108 static int
1109 svm_range_split_tail(struct svm_range *prange, uint64_t new_last,
1110 		     struct list_head *insert_list, struct list_head *remap_list)
1111 {
1112 	struct svm_range *tail;
1113 	int r = svm_range_split(prange, prange->start, new_last, &tail);
1114 
1115 	if (!r) {
1116 		list_add(&tail->list, insert_list);
1117 		if (!IS_ALIGNED(new_last + 1, 1UL << prange->granularity))
1118 			list_add(&tail->update_list, remap_list);
1119 	}
1120 	return r;
1121 }
1122 
1123 static int
1124 svm_range_split_head(struct svm_range *prange, uint64_t new_start,
1125 		     struct list_head *insert_list, struct list_head *remap_list)
1126 {
1127 	struct svm_range *head;
1128 	int r = svm_range_split(prange, new_start, prange->last, &head);
1129 
1130 	if (!r) {
1131 		list_add(&head->list, insert_list);
1132 		if (!IS_ALIGNED(new_start, 1UL << prange->granularity))
1133 			list_add(&head->update_list, remap_list);
1134 	}
1135 	return r;
1136 }
1137 
1138 static void
1139 svm_range_add_child(struct svm_range *prange, struct mm_struct *mm,
1140 		    struct svm_range *pchild, enum svm_work_list_ops op)
1141 {
1142 	pr_debug("add child 0x%p [0x%lx 0x%lx] to prange 0x%p child list %d\n",
1143 		 pchild, pchild->start, pchild->last, prange, op);
1144 
1145 	pchild->work_item.mm = mm;
1146 	pchild->work_item.op = op;
1147 	list_add_tail(&pchild->child_list, &prange->child_list);
1148 }
1149 
1150 static bool
1151 svm_nodes_in_same_hive(struct kfd_node *node_a, struct kfd_node *node_b)
1152 {
1153 	return (node_a->adev == node_b->adev ||
1154 		amdgpu_xgmi_same_hive(node_a->adev, node_b->adev));
1155 }
1156 
1157 static uint64_t
1158 svm_range_get_pte_flags(struct kfd_node *node,
1159 			struct svm_range *prange, int domain)
1160 {
1161 	struct kfd_node *bo_node;
1162 	uint32_t flags = prange->flags;
1163 	uint32_t mapping_flags = 0;
1164 	uint64_t pte_flags;
1165 	bool snoop = (domain != SVM_RANGE_VRAM_DOMAIN);
1166 	bool coherent = flags & (KFD_IOCTL_SVM_FLAG_COHERENT | KFD_IOCTL_SVM_FLAG_EXT_COHERENT);
1167 	bool ext_coherent = flags & KFD_IOCTL_SVM_FLAG_EXT_COHERENT;
1168 	bool uncached = false; /*flags & KFD_IOCTL_SVM_FLAG_UNCACHED;*/
1169 	unsigned int mtype_local;
1170 
1171 	if (domain == SVM_RANGE_VRAM_DOMAIN)
1172 		bo_node = prange->svm_bo->node;
1173 
1174 	switch (amdgpu_ip_version(node->adev, GC_HWIP, 0)) {
1175 	case IP_VERSION(9, 4, 1):
1176 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1177 			if (bo_node == node) {
1178 				mapping_flags |= coherent ?
1179 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1180 			} else {
1181 				mapping_flags |= coherent ?
1182 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1183 				if (svm_nodes_in_same_hive(node, bo_node))
1184 					snoop = true;
1185 			}
1186 		} else {
1187 			mapping_flags |= coherent ?
1188 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1189 		}
1190 		break;
1191 	case IP_VERSION(9, 4, 2):
1192 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1193 			if (bo_node == node) {
1194 				mapping_flags |= coherent ?
1195 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1196 				if (node->adev->gmc.xgmi.connected_to_cpu)
1197 					snoop = true;
1198 			} else {
1199 				mapping_flags |= coherent ?
1200 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1201 				if (svm_nodes_in_same_hive(node, bo_node))
1202 					snoop = true;
1203 			}
1204 		} else {
1205 			mapping_flags |= coherent ?
1206 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1207 		}
1208 		break;
1209 	case IP_VERSION(9, 4, 3):
1210 		mtype_local = amdgpu_mtype_local == 1 ? AMDGPU_VM_MTYPE_NC :
1211 			      (amdgpu_mtype_local == 2 || ext_coherent ?
1212 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW);
1213 		snoop = true;
1214 		if (uncached) {
1215 			mapping_flags |= AMDGPU_VM_MTYPE_UC;
1216 		} else if (domain == SVM_RANGE_VRAM_DOMAIN) {
1217 			/* local HBM region close to partition */
1218 			if (bo_node->adev == node->adev &&
1219 			    (!bo_node->xcp || !node->xcp || bo_node->xcp->mem_id == node->xcp->mem_id))
1220 				mapping_flags |= mtype_local;
1221 			/* local HBM region far from partition or remote XGMI GPU
1222 			 * with regular system scope coherence
1223 			 */
1224 			else if (svm_nodes_in_same_hive(bo_node, node) && !ext_coherent)
1225 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1226 			/* PCIe P2P or extended system scope coherence */
1227 			else
1228 				mapping_flags |= AMDGPU_VM_MTYPE_UC;
1229 		/* system memory accessed by the APU */
1230 		} else if (node->adev->flags & AMD_IS_APU) {
1231 			/* On NUMA systems, locality is determined per-page
1232 			 * in amdgpu_gmc_override_vm_pte_flags
1233 			 */
1234 			if (num_possible_nodes() <= 1)
1235 				mapping_flags |= mtype_local;
1236 			else
1237 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1238 		/* system memory accessed by the dGPU */
1239 		} else {
1240 			mapping_flags |= AMDGPU_VM_MTYPE_UC;
1241 		}
1242 		break;
1243 	default:
1244 		mapping_flags |= coherent ?
1245 			AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1246 	}
1247 
1248 	mapping_flags |= AMDGPU_VM_PAGE_READABLE | AMDGPU_VM_PAGE_WRITEABLE;
1249 
1250 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_RO)
1251 		mapping_flags &= ~AMDGPU_VM_PAGE_WRITEABLE;
1252 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_EXEC)
1253 		mapping_flags |= AMDGPU_VM_PAGE_EXECUTABLE;
1254 
1255 	pte_flags = AMDGPU_PTE_VALID;
1256 	pte_flags |= (domain == SVM_RANGE_VRAM_DOMAIN) ? 0 : AMDGPU_PTE_SYSTEM;
1257 	pte_flags |= snoop ? AMDGPU_PTE_SNOOPED : 0;
1258 
1259 	pte_flags |= amdgpu_gem_va_map_flags(node->adev, mapping_flags);
1260 	return pte_flags;
1261 }
1262 
1263 static int
1264 svm_range_unmap_from_gpu(struct amdgpu_device *adev, struct amdgpu_vm *vm,
1265 			 uint64_t start, uint64_t last,
1266 			 struct dma_fence **fence)
1267 {
1268 	uint64_t init_pte_value = 0;
1269 
1270 	pr_debug("[0x%llx 0x%llx]\n", start, last);
1271 
1272 	return amdgpu_vm_update_range(adev, vm, false, true, true, NULL, start,
1273 				      last, init_pte_value, 0, 0, NULL, NULL,
1274 				      fence);
1275 }
1276 
1277 static int
1278 svm_range_unmap_from_gpus(struct svm_range *prange, unsigned long start,
1279 			  unsigned long last, uint32_t trigger)
1280 {
1281 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1282 	struct kfd_process_device *pdd;
1283 	struct dma_fence *fence = NULL;
1284 	struct kfd_process *p;
1285 	uint32_t gpuidx;
1286 	int r = 0;
1287 
1288 	if (!prange->mapped_to_gpu) {
1289 		pr_debug("prange 0x%p [0x%lx 0x%lx] not mapped to GPU\n",
1290 			 prange, prange->start, prange->last);
1291 		return 0;
1292 	}
1293 
1294 	if (prange->start == start && prange->last == last) {
1295 		pr_debug("unmap svms 0x%p prange 0x%p\n", prange->svms, prange);
1296 		prange->mapped_to_gpu = false;
1297 	}
1298 
1299 	bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
1300 		  MAX_GPU_INSTANCE);
1301 	p = container_of(prange->svms, struct kfd_process, svms);
1302 
1303 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1304 		pr_debug("unmap from gpu idx 0x%x\n", gpuidx);
1305 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1306 		if (!pdd) {
1307 			pr_debug("failed to find device idx %d\n", gpuidx);
1308 			return -EINVAL;
1309 		}
1310 
1311 		kfd_smi_event_unmap_from_gpu(pdd->dev, p->lead_thread->pid,
1312 					     start, last, trigger);
1313 
1314 		r = svm_range_unmap_from_gpu(pdd->dev->adev,
1315 					     drm_priv_to_vm(pdd->drm_priv),
1316 					     start, last, &fence);
1317 		if (r)
1318 			break;
1319 
1320 		if (fence) {
1321 			r = dma_fence_wait(fence, false);
1322 			dma_fence_put(fence);
1323 			fence = NULL;
1324 			if (r)
1325 				break;
1326 		}
1327 		kfd_flush_tlb(pdd, TLB_FLUSH_HEAVYWEIGHT);
1328 	}
1329 
1330 	return r;
1331 }
1332 
1333 static int
1334 svm_range_map_to_gpu(struct kfd_process_device *pdd, struct svm_range *prange,
1335 		     unsigned long offset, unsigned long npages, bool readonly,
1336 		     dma_addr_t *dma_addr, struct amdgpu_device *bo_adev,
1337 		     struct dma_fence **fence, bool flush_tlb)
1338 {
1339 	struct amdgpu_device *adev = pdd->dev->adev;
1340 	struct amdgpu_vm *vm = drm_priv_to_vm(pdd->drm_priv);
1341 	uint64_t pte_flags;
1342 	unsigned long last_start;
1343 	int last_domain;
1344 	int r = 0;
1345 	int64_t i, j;
1346 
1347 	last_start = prange->start + offset;
1348 
1349 	pr_debug("svms 0x%p [0x%lx 0x%lx] readonly %d\n", prange->svms,
1350 		 last_start, last_start + npages - 1, readonly);
1351 
1352 	for (i = offset; i < offset + npages; i++) {
1353 		last_domain = dma_addr[i] & SVM_RANGE_VRAM_DOMAIN;
1354 		dma_addr[i] &= ~SVM_RANGE_VRAM_DOMAIN;
1355 
1356 		/* Collect all pages in the same address range and memory domain
1357 		 * that can be mapped with a single call to update mapping.
1358 		 */
1359 		if (i < offset + npages - 1 &&
1360 		    last_domain == (dma_addr[i + 1] & SVM_RANGE_VRAM_DOMAIN))
1361 			continue;
1362 
1363 		pr_debug("Mapping range [0x%lx 0x%llx] on domain: %s\n",
1364 			 last_start, prange->start + i, last_domain ? "GPU" : "CPU");
1365 
1366 		pte_flags = svm_range_get_pte_flags(pdd->dev, prange, last_domain);
1367 		if (readonly)
1368 			pte_flags &= ~AMDGPU_PTE_WRITEABLE;
1369 
1370 		pr_debug("svms 0x%p map [0x%lx 0x%llx] vram %d PTE 0x%llx\n",
1371 			 prange->svms, last_start, prange->start + i,
1372 			 (last_domain == SVM_RANGE_VRAM_DOMAIN) ? 1 : 0,
1373 			 pte_flags);
1374 
1375 		/* For dGPU mode, we use same vm_manager to allocate VRAM for
1376 		 * different memory partition based on fpfn/lpfn, we should use
1377 		 * same vm_manager.vram_base_offset regardless memory partition.
1378 		 */
1379 		r = amdgpu_vm_update_range(adev, vm, false, false, flush_tlb, NULL,
1380 					   last_start, prange->start + i,
1381 					   pte_flags,
1382 					   (last_start - prange->start) << PAGE_SHIFT,
1383 					   bo_adev ? bo_adev->vm_manager.vram_base_offset : 0,
1384 					   NULL, dma_addr, &vm->last_update);
1385 
1386 		for (j = last_start - prange->start; j <= i; j++)
1387 			dma_addr[j] |= last_domain;
1388 
1389 		if (r) {
1390 			pr_debug("failed %d to map to gpu 0x%lx\n", r, prange->start);
1391 			goto out;
1392 		}
1393 		last_start = prange->start + i + 1;
1394 	}
1395 
1396 	r = amdgpu_vm_update_pdes(adev, vm, false);
1397 	if (r) {
1398 		pr_debug("failed %d to update directories 0x%lx\n", r,
1399 			 prange->start);
1400 		goto out;
1401 	}
1402 
1403 	if (fence)
1404 		*fence = dma_fence_get(vm->last_update);
1405 
1406 out:
1407 	return r;
1408 }
1409 
1410 static int
1411 svm_range_map_to_gpus(struct svm_range *prange, unsigned long offset,
1412 		      unsigned long npages, bool readonly,
1413 		      unsigned long *bitmap, bool wait, bool flush_tlb)
1414 {
1415 	struct kfd_process_device *pdd;
1416 	struct amdgpu_device *bo_adev = NULL;
1417 	struct kfd_process *p;
1418 	struct dma_fence *fence = NULL;
1419 	uint32_t gpuidx;
1420 	int r = 0;
1421 
1422 	if (prange->svm_bo && prange->ttm_res)
1423 		bo_adev = prange->svm_bo->node->adev;
1424 
1425 	p = container_of(prange->svms, struct kfd_process, svms);
1426 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1427 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
1428 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1429 		if (!pdd) {
1430 			pr_debug("failed to find device idx %d\n", gpuidx);
1431 			return -EINVAL;
1432 		}
1433 
1434 		pdd = kfd_bind_process_to_device(pdd->dev, p);
1435 		if (IS_ERR(pdd))
1436 			return -EINVAL;
1437 
1438 		if (bo_adev && pdd->dev->adev != bo_adev &&
1439 		    !amdgpu_xgmi_same_hive(pdd->dev->adev, bo_adev)) {
1440 			pr_debug("cannot map to device idx %d\n", gpuidx);
1441 			continue;
1442 		}
1443 
1444 		r = svm_range_map_to_gpu(pdd, prange, offset, npages, readonly,
1445 					 prange->dma_addr[gpuidx],
1446 					 bo_adev, wait ? &fence : NULL,
1447 					 flush_tlb);
1448 		if (r)
1449 			break;
1450 
1451 		if (fence) {
1452 			r = dma_fence_wait(fence, false);
1453 			dma_fence_put(fence);
1454 			fence = NULL;
1455 			if (r) {
1456 				pr_debug("failed %d to dma fence wait\n", r);
1457 				break;
1458 			}
1459 		}
1460 
1461 		kfd_flush_tlb(pdd, TLB_FLUSH_LEGACY);
1462 	}
1463 
1464 	return r;
1465 }
1466 
1467 struct svm_validate_context {
1468 	struct kfd_process *process;
1469 	struct svm_range *prange;
1470 	bool intr;
1471 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1472 	struct drm_exec exec;
1473 };
1474 
1475 static int svm_range_reserve_bos(struct svm_validate_context *ctx, bool intr)
1476 {
1477 	struct kfd_process_device *pdd;
1478 	struct amdgpu_vm *vm;
1479 	uint32_t gpuidx;
1480 	int r;
1481 
1482 	drm_exec_init(&ctx->exec, intr ? DRM_EXEC_INTERRUPTIBLE_WAIT: 0);
1483 	drm_exec_until_all_locked(&ctx->exec) {
1484 		for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1485 			pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1486 			if (!pdd) {
1487 				pr_debug("failed to find device idx %d\n", gpuidx);
1488 				r = -EINVAL;
1489 				goto unreserve_out;
1490 			}
1491 			vm = drm_priv_to_vm(pdd->drm_priv);
1492 
1493 			r = amdgpu_vm_lock_pd(vm, &ctx->exec, 2);
1494 			drm_exec_retry_on_contention(&ctx->exec);
1495 			if (unlikely(r)) {
1496 				pr_debug("failed %d to reserve bo\n", r);
1497 				goto unreserve_out;
1498 			}
1499 		}
1500 	}
1501 
1502 	for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1503 		pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1504 		if (!pdd) {
1505 			pr_debug("failed to find device idx %d\n", gpuidx);
1506 			r = -EINVAL;
1507 			goto unreserve_out;
1508 		}
1509 
1510 		r = amdgpu_vm_validate_pt_bos(pdd->dev->adev,
1511 					      drm_priv_to_vm(pdd->drm_priv),
1512 					      svm_range_bo_validate, NULL);
1513 		if (r) {
1514 			pr_debug("failed %d validate pt bos\n", r);
1515 			goto unreserve_out;
1516 		}
1517 	}
1518 
1519 	return 0;
1520 
1521 unreserve_out:
1522 	drm_exec_fini(&ctx->exec);
1523 	return r;
1524 }
1525 
1526 static void svm_range_unreserve_bos(struct svm_validate_context *ctx)
1527 {
1528 	drm_exec_fini(&ctx->exec);
1529 }
1530 
1531 static void *kfd_svm_page_owner(struct kfd_process *p, int32_t gpuidx)
1532 {
1533 	struct kfd_process_device *pdd;
1534 
1535 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1536 	if (!pdd)
1537 		return NULL;
1538 
1539 	return SVM_ADEV_PGMAP_OWNER(pdd->dev->adev);
1540 }
1541 
1542 /*
1543  * Validation+GPU mapping with concurrent invalidation (MMU notifiers)
1544  *
1545  * To prevent concurrent destruction or change of range attributes, the
1546  * svm_read_lock must be held. The caller must not hold the svm_write_lock
1547  * because that would block concurrent evictions and lead to deadlocks. To
1548  * serialize concurrent migrations or validations of the same range, the
1549  * prange->migrate_mutex must be held.
1550  *
1551  * For VRAM ranges, the SVM BO must be allocated and valid (protected by its
1552  * eviction fence.
1553  *
1554  * The following sequence ensures race-free validation and GPU mapping:
1555  *
1556  * 1. Reserve page table (and SVM BO if range is in VRAM)
1557  * 2. hmm_range_fault to get page addresses (if system memory)
1558  * 3. DMA-map pages (if system memory)
1559  * 4-a. Take notifier lock
1560  * 4-b. Check that pages still valid (mmu_interval_read_retry)
1561  * 4-c. Check that the range was not split or otherwise invalidated
1562  * 4-d. Update GPU page table
1563  * 4.e. Release notifier lock
1564  * 5. Release page table (and SVM BO) reservation
1565  */
1566 static int svm_range_validate_and_map(struct mm_struct *mm,
1567 				      struct svm_range *prange, int32_t gpuidx,
1568 				      bool intr, bool wait, bool flush_tlb)
1569 {
1570 	struct svm_validate_context *ctx;
1571 	unsigned long start, end, addr;
1572 	struct kfd_process *p;
1573 	uint64_t vram_pages;
1574 	void *owner;
1575 	int32_t idx;
1576 	int r = 0;
1577 
1578 	ctx = kzalloc(sizeof(struct svm_validate_context), GFP_KERNEL);
1579 	if (!ctx)
1580 		return -ENOMEM;
1581 	ctx->process = container_of(prange->svms, struct kfd_process, svms);
1582 	ctx->prange = prange;
1583 	ctx->intr = intr;
1584 
1585 	if (gpuidx < MAX_GPU_INSTANCE) {
1586 		bitmap_zero(ctx->bitmap, MAX_GPU_INSTANCE);
1587 		bitmap_set(ctx->bitmap, gpuidx, 1);
1588 	} else if (ctx->process->xnack_enabled) {
1589 		bitmap_copy(ctx->bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
1590 
1591 		/* If prefetch range to GPU, or GPU retry fault migrate range to
1592 		 * GPU, which has ACCESS attribute to the range, create mapping
1593 		 * on that GPU.
1594 		 */
1595 		if (prange->actual_loc) {
1596 			gpuidx = kfd_process_gpuidx_from_gpuid(ctx->process,
1597 							prange->actual_loc);
1598 			if (gpuidx < 0) {
1599 				WARN_ONCE(1, "failed get device by id 0x%x\n",
1600 					 prange->actual_loc);
1601 				r = -EINVAL;
1602 				goto free_ctx;
1603 			}
1604 			if (test_bit(gpuidx, prange->bitmap_access))
1605 				bitmap_set(ctx->bitmap, gpuidx, 1);
1606 		}
1607 	} else {
1608 		bitmap_or(ctx->bitmap, prange->bitmap_access,
1609 			  prange->bitmap_aip, MAX_GPU_INSTANCE);
1610 	}
1611 
1612 	if (bitmap_empty(ctx->bitmap, MAX_GPU_INSTANCE)) {
1613 		bitmap_copy(ctx->bitmap, prange->bitmap_access, MAX_GPU_INSTANCE);
1614 		if (!prange->mapped_to_gpu ||
1615 		    bitmap_empty(ctx->bitmap, MAX_GPU_INSTANCE)) {
1616 			r = 0;
1617 			goto free_ctx;
1618 		}
1619 	}
1620 
1621 	if (prange->actual_loc && !prange->ttm_res) {
1622 		/* This should never happen. actual_loc gets set by
1623 		 * svm_migrate_ram_to_vram after allocating a BO.
1624 		 */
1625 		WARN_ONCE(1, "VRAM BO missing during validation\n");
1626 		r = -EINVAL;
1627 		goto free_ctx;
1628 	}
1629 
1630 	svm_range_reserve_bos(ctx, intr);
1631 
1632 	p = container_of(prange->svms, struct kfd_process, svms);
1633 	owner = kfd_svm_page_owner(p, find_first_bit(ctx->bitmap,
1634 						MAX_GPU_INSTANCE));
1635 	for_each_set_bit(idx, ctx->bitmap, MAX_GPU_INSTANCE) {
1636 		if (kfd_svm_page_owner(p, idx) != owner) {
1637 			owner = NULL;
1638 			break;
1639 		}
1640 	}
1641 
1642 	vram_pages = 0;
1643 	start = prange->start << PAGE_SHIFT;
1644 	end = (prange->last + 1) << PAGE_SHIFT;
1645 	for (addr = start; !r && addr < end; ) {
1646 		struct hmm_range *hmm_range;
1647 		struct vm_area_struct *vma;
1648 		uint64_t vram_pages_vma;
1649 		unsigned long next = 0;
1650 		unsigned long offset;
1651 		unsigned long npages;
1652 		bool readonly;
1653 
1654 		vma = vma_lookup(mm, addr);
1655 		if (vma) {
1656 			readonly = !(vma->vm_flags & VM_WRITE);
1657 
1658 			next = min(vma->vm_end, end);
1659 			npages = (next - addr) >> PAGE_SHIFT;
1660 			WRITE_ONCE(p->svms.faulting_task, current);
1661 			r = amdgpu_hmm_range_get_pages(&prange->notifier, addr, npages,
1662 						       readonly, owner, NULL,
1663 						       &hmm_range);
1664 			WRITE_ONCE(p->svms.faulting_task, NULL);
1665 			if (r) {
1666 				pr_debug("failed %d to get svm range pages\n", r);
1667 				if (r == -EBUSY)
1668 					r = -EAGAIN;
1669 			}
1670 		} else {
1671 			r = -EFAULT;
1672 		}
1673 
1674 		if (!r) {
1675 			offset = (addr - start) >> PAGE_SHIFT;
1676 			r = svm_range_dma_map(prange, ctx->bitmap, offset, npages,
1677 					      hmm_range->hmm_pfns, &vram_pages_vma);
1678 			if (r)
1679 				pr_debug("failed %d to dma map range\n", r);
1680 			else
1681 				vram_pages += vram_pages_vma;
1682 		}
1683 
1684 		svm_range_lock(prange);
1685 		if (!r && amdgpu_hmm_range_get_pages_done(hmm_range)) {
1686 			pr_debug("hmm update the range, need validate again\n");
1687 			r = -EAGAIN;
1688 		}
1689 
1690 		if (!r && !list_empty(&prange->child_list)) {
1691 			pr_debug("range split by unmap in parallel, validate again\n");
1692 			r = -EAGAIN;
1693 		}
1694 
1695 		if (!r)
1696 			r = svm_range_map_to_gpus(prange, offset, npages, readonly,
1697 						  ctx->bitmap, wait, flush_tlb);
1698 
1699 		if (!r && next == end)
1700 			prange->mapped_to_gpu = true;
1701 
1702 		svm_range_unlock(prange);
1703 
1704 		addr = next;
1705 	}
1706 
1707 	if (addr == end) {
1708 		prange->vram_pages = vram_pages;
1709 
1710 		/* if prange does not include any vram page and it
1711 		 * has not released svm_bo drop its svm_bo reference
1712 		 * and set its actaul_loc to sys ram
1713 		 */
1714 		if (!vram_pages && prange->ttm_res) {
1715 			prange->actual_loc = 0;
1716 			svm_range_vram_node_free(prange);
1717 		}
1718 	}
1719 
1720 	svm_range_unreserve_bos(ctx);
1721 	if (!r)
1722 		prange->validate_timestamp = ktime_get_boottime();
1723 
1724 free_ctx:
1725 	kfree(ctx);
1726 
1727 	return r;
1728 }
1729 
1730 /**
1731  * svm_range_list_lock_and_flush_work - flush pending deferred work
1732  *
1733  * @svms: the svm range list
1734  * @mm: the mm structure
1735  *
1736  * Context: Returns with mmap write lock held, pending deferred work flushed
1737  *
1738  */
1739 void
1740 svm_range_list_lock_and_flush_work(struct svm_range_list *svms,
1741 				   struct mm_struct *mm)
1742 {
1743 retry_flush_work:
1744 	flush_work(&svms->deferred_list_work);
1745 	mmap_write_lock(mm);
1746 
1747 	if (list_empty(&svms->deferred_range_list))
1748 		return;
1749 	mmap_write_unlock(mm);
1750 	pr_debug("retry flush\n");
1751 	goto retry_flush_work;
1752 }
1753 
1754 static void svm_range_restore_work(struct work_struct *work)
1755 {
1756 	struct delayed_work *dwork = to_delayed_work(work);
1757 	struct amdkfd_process_info *process_info;
1758 	struct svm_range_list *svms;
1759 	struct svm_range *prange;
1760 	struct kfd_process *p;
1761 	struct mm_struct *mm;
1762 	int evicted_ranges;
1763 	int invalid;
1764 	int r;
1765 
1766 	svms = container_of(dwork, struct svm_range_list, restore_work);
1767 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1768 	if (!evicted_ranges)
1769 		return;
1770 
1771 	pr_debug("restore svm ranges\n");
1772 
1773 	p = container_of(svms, struct kfd_process, svms);
1774 	process_info = p->kgd_process_info;
1775 
1776 	/* Keep mm reference when svm_range_validate_and_map ranges */
1777 	mm = get_task_mm(p->lead_thread);
1778 	if (!mm) {
1779 		pr_debug("svms 0x%p process mm gone\n", svms);
1780 		return;
1781 	}
1782 
1783 	mutex_lock(&process_info->lock);
1784 	svm_range_list_lock_and_flush_work(svms, mm);
1785 	mutex_lock(&svms->lock);
1786 
1787 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1788 
1789 	list_for_each_entry(prange, &svms->list, list) {
1790 		invalid = atomic_read(&prange->invalid);
1791 		if (!invalid)
1792 			continue;
1793 
1794 		pr_debug("restoring svms 0x%p prange 0x%p [0x%lx %lx] inv %d\n",
1795 			 prange->svms, prange, prange->start, prange->last,
1796 			 invalid);
1797 
1798 		/*
1799 		 * If range is migrating, wait for migration is done.
1800 		 */
1801 		mutex_lock(&prange->migrate_mutex);
1802 
1803 		r = svm_range_validate_and_map(mm, prange, MAX_GPU_INSTANCE,
1804 					       false, true, false);
1805 		if (r)
1806 			pr_debug("failed %d to map 0x%lx to gpus\n", r,
1807 				 prange->start);
1808 
1809 		mutex_unlock(&prange->migrate_mutex);
1810 		if (r)
1811 			goto out_reschedule;
1812 
1813 		if (atomic_cmpxchg(&prange->invalid, invalid, 0) != invalid)
1814 			goto out_reschedule;
1815 	}
1816 
1817 	if (atomic_cmpxchg(&svms->evicted_ranges, evicted_ranges, 0) !=
1818 	    evicted_ranges)
1819 		goto out_reschedule;
1820 
1821 	evicted_ranges = 0;
1822 
1823 	r = kgd2kfd_resume_mm(mm);
1824 	if (r) {
1825 		/* No recovery from this failure. Probably the CP is
1826 		 * hanging. No point trying again.
1827 		 */
1828 		pr_debug("failed %d to resume KFD\n", r);
1829 	}
1830 
1831 	pr_debug("restore svm ranges successfully\n");
1832 
1833 out_reschedule:
1834 	mutex_unlock(&svms->lock);
1835 	mmap_write_unlock(mm);
1836 	mutex_unlock(&process_info->lock);
1837 
1838 	/* If validation failed, reschedule another attempt */
1839 	if (evicted_ranges) {
1840 		pr_debug("reschedule to restore svm range\n");
1841 		schedule_delayed_work(&svms->restore_work,
1842 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1843 
1844 		kfd_smi_event_queue_restore_rescheduled(mm);
1845 	}
1846 	mmput(mm);
1847 }
1848 
1849 /**
1850  * svm_range_evict - evict svm range
1851  * @prange: svm range structure
1852  * @mm: current process mm_struct
1853  * @start: starting process queue number
1854  * @last: last process queue number
1855  * @event: mmu notifier event when range is evicted or migrated
1856  *
1857  * Stop all queues of the process to ensure GPU doesn't access the memory, then
1858  * return to let CPU evict the buffer and proceed CPU pagetable update.
1859  *
1860  * Don't need use lock to sync cpu pagetable invalidation with GPU execution.
1861  * If invalidation happens while restore work is running, restore work will
1862  * restart to ensure to get the latest CPU pages mapping to GPU, then start
1863  * the queues.
1864  */
1865 static int
1866 svm_range_evict(struct svm_range *prange, struct mm_struct *mm,
1867 		unsigned long start, unsigned long last,
1868 		enum mmu_notifier_event event)
1869 {
1870 	struct svm_range_list *svms = prange->svms;
1871 	struct svm_range *pchild;
1872 	struct kfd_process *p;
1873 	int r = 0;
1874 
1875 	p = container_of(svms, struct kfd_process, svms);
1876 
1877 	pr_debug("invalidate svms 0x%p prange [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
1878 		 svms, prange->start, prange->last, start, last);
1879 
1880 	if (!p->xnack_enabled ||
1881 	    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) {
1882 		int evicted_ranges;
1883 		bool mapped = prange->mapped_to_gpu;
1884 
1885 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1886 			if (!pchild->mapped_to_gpu)
1887 				continue;
1888 			mapped = true;
1889 			mutex_lock_nested(&pchild->lock, 1);
1890 			if (pchild->start <= last && pchild->last >= start) {
1891 				pr_debug("increment pchild invalid [0x%lx 0x%lx]\n",
1892 					 pchild->start, pchild->last);
1893 				atomic_inc(&pchild->invalid);
1894 			}
1895 			mutex_unlock(&pchild->lock);
1896 		}
1897 
1898 		if (!mapped)
1899 			return r;
1900 
1901 		if (prange->start <= last && prange->last >= start)
1902 			atomic_inc(&prange->invalid);
1903 
1904 		evicted_ranges = atomic_inc_return(&svms->evicted_ranges);
1905 		if (evicted_ranges != 1)
1906 			return r;
1907 
1908 		pr_debug("evicting svms 0x%p range [0x%lx 0x%lx]\n",
1909 			 prange->svms, prange->start, prange->last);
1910 
1911 		/* First eviction, stop the queues */
1912 		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_SVM);
1913 		if (r)
1914 			pr_debug("failed to quiesce KFD\n");
1915 
1916 		pr_debug("schedule to restore svm %p ranges\n", svms);
1917 		schedule_delayed_work(&svms->restore_work,
1918 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1919 	} else {
1920 		unsigned long s, l;
1921 		uint32_t trigger;
1922 
1923 		if (event == MMU_NOTIFY_MIGRATE)
1924 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY_MIGRATE;
1925 		else
1926 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY;
1927 
1928 		pr_debug("invalidate unmap svms 0x%p [0x%lx 0x%lx] from GPUs\n",
1929 			 prange->svms, start, last);
1930 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1931 			mutex_lock_nested(&pchild->lock, 1);
1932 			s = max(start, pchild->start);
1933 			l = min(last, pchild->last);
1934 			if (l >= s)
1935 				svm_range_unmap_from_gpus(pchild, s, l, trigger);
1936 			mutex_unlock(&pchild->lock);
1937 		}
1938 		s = max(start, prange->start);
1939 		l = min(last, prange->last);
1940 		if (l >= s)
1941 			svm_range_unmap_from_gpus(prange, s, l, trigger);
1942 	}
1943 
1944 	return r;
1945 }
1946 
1947 static struct svm_range *svm_range_clone(struct svm_range *old)
1948 {
1949 	struct svm_range *new;
1950 
1951 	new = svm_range_new(old->svms, old->start, old->last, false);
1952 	if (!new)
1953 		return NULL;
1954 	if (svm_range_copy_dma_addrs(new, old)) {
1955 		svm_range_free(new, false);
1956 		return NULL;
1957 	}
1958 	if (old->svm_bo) {
1959 		new->ttm_res = old->ttm_res;
1960 		new->offset = old->offset;
1961 		new->svm_bo = svm_range_bo_ref(old->svm_bo);
1962 		spin_lock(&new->svm_bo->list_lock);
1963 		list_add(&new->svm_bo_list, &new->svm_bo->range_list);
1964 		spin_unlock(&new->svm_bo->list_lock);
1965 	}
1966 	new->flags = old->flags;
1967 	new->preferred_loc = old->preferred_loc;
1968 	new->prefetch_loc = old->prefetch_loc;
1969 	new->actual_loc = old->actual_loc;
1970 	new->granularity = old->granularity;
1971 	new->mapped_to_gpu = old->mapped_to_gpu;
1972 	new->vram_pages = old->vram_pages;
1973 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
1974 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
1975 
1976 	return new;
1977 }
1978 
1979 void svm_range_set_max_pages(struct amdgpu_device *adev)
1980 {
1981 	uint64_t max_pages;
1982 	uint64_t pages, _pages;
1983 	uint64_t min_pages = 0;
1984 	int i, id;
1985 
1986 	for (i = 0; i < adev->kfd.dev->num_nodes; i++) {
1987 		if (adev->kfd.dev->nodes[i]->xcp)
1988 			id = adev->kfd.dev->nodes[i]->xcp->id;
1989 		else
1990 			id = -1;
1991 		pages = KFD_XCP_MEMORY_SIZE(adev, id) >> 17;
1992 		pages = clamp(pages, 1ULL << 9, 1ULL << 18);
1993 		pages = rounddown_pow_of_two(pages);
1994 		min_pages = min_not_zero(min_pages, pages);
1995 	}
1996 
1997 	do {
1998 		max_pages = READ_ONCE(max_svm_range_pages);
1999 		_pages = min_not_zero(max_pages, min_pages);
2000 	} while (cmpxchg(&max_svm_range_pages, max_pages, _pages) != max_pages);
2001 }
2002 
2003 static int
2004 svm_range_split_new(struct svm_range_list *svms, uint64_t start, uint64_t last,
2005 		    uint64_t max_pages, struct list_head *insert_list,
2006 		    struct list_head *update_list)
2007 {
2008 	struct svm_range *prange;
2009 	uint64_t l;
2010 
2011 	pr_debug("max_svm_range_pages 0x%llx adding [0x%llx 0x%llx]\n",
2012 		 max_pages, start, last);
2013 
2014 	while (last >= start) {
2015 		l = min(last, ALIGN_DOWN(start + max_pages, max_pages) - 1);
2016 
2017 		prange = svm_range_new(svms, start, l, true);
2018 		if (!prange)
2019 			return -ENOMEM;
2020 		list_add(&prange->list, insert_list);
2021 		list_add(&prange->update_list, update_list);
2022 
2023 		start = l + 1;
2024 	}
2025 	return 0;
2026 }
2027 
2028 /**
2029  * svm_range_add - add svm range and handle overlap
2030  * @p: the range add to this process svms
2031  * @start: page size aligned
2032  * @size: page size aligned
2033  * @nattr: number of attributes
2034  * @attrs: array of attributes
2035  * @update_list: output, the ranges need validate and update GPU mapping
2036  * @insert_list: output, the ranges need insert to svms
2037  * @remove_list: output, the ranges are replaced and need remove from svms
2038  * @remap_list: output, remap unaligned svm ranges
2039  *
2040  * Check if the virtual address range has overlap with any existing ranges,
2041  * split partly overlapping ranges and add new ranges in the gaps. All changes
2042  * should be applied to the range_list and interval tree transactionally. If
2043  * any range split or allocation fails, the entire update fails. Therefore any
2044  * existing overlapping svm_ranges are cloned and the original svm_ranges left
2045  * unchanged.
2046  *
2047  * If the transaction succeeds, the caller can update and insert clones and
2048  * new ranges, then free the originals.
2049  *
2050  * Otherwise the caller can free the clones and new ranges, while the old
2051  * svm_ranges remain unchanged.
2052  *
2053  * Context: Process context, caller must hold svms->lock
2054  *
2055  * Return:
2056  * 0 - OK, otherwise error code
2057  */
2058 static int
2059 svm_range_add(struct kfd_process *p, uint64_t start, uint64_t size,
2060 	      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
2061 	      struct list_head *update_list, struct list_head *insert_list,
2062 	      struct list_head *remove_list, struct list_head *remap_list)
2063 {
2064 	unsigned long last = start + size - 1UL;
2065 	struct svm_range_list *svms = &p->svms;
2066 	struct interval_tree_node *node;
2067 	struct svm_range *prange;
2068 	struct svm_range *tmp;
2069 	struct list_head new_list;
2070 	int r = 0;
2071 
2072 	pr_debug("svms 0x%p [0x%llx 0x%lx]\n", &p->svms, start, last);
2073 
2074 	INIT_LIST_HEAD(update_list);
2075 	INIT_LIST_HEAD(insert_list);
2076 	INIT_LIST_HEAD(remove_list);
2077 	INIT_LIST_HEAD(&new_list);
2078 	INIT_LIST_HEAD(remap_list);
2079 
2080 	node = interval_tree_iter_first(&svms->objects, start, last);
2081 	while (node) {
2082 		struct interval_tree_node *next;
2083 		unsigned long next_start;
2084 
2085 		pr_debug("found overlap node [0x%lx 0x%lx]\n", node->start,
2086 			 node->last);
2087 
2088 		prange = container_of(node, struct svm_range, it_node);
2089 		next = interval_tree_iter_next(node, start, last);
2090 		next_start = min(node->last, last) + 1;
2091 
2092 		if (svm_range_is_same_attrs(p, prange, nattr, attrs) &&
2093 		    prange->mapped_to_gpu) {
2094 			/* nothing to do */
2095 		} else if (node->start < start || node->last > last) {
2096 			/* node intersects the update range and its attributes
2097 			 * will change. Clone and split it, apply updates only
2098 			 * to the overlapping part
2099 			 */
2100 			struct svm_range *old = prange;
2101 
2102 			prange = svm_range_clone(old);
2103 			if (!prange) {
2104 				r = -ENOMEM;
2105 				goto out;
2106 			}
2107 
2108 			list_add(&old->update_list, remove_list);
2109 			list_add(&prange->list, insert_list);
2110 			list_add(&prange->update_list, update_list);
2111 
2112 			if (node->start < start) {
2113 				pr_debug("change old range start\n");
2114 				r = svm_range_split_head(prange, start,
2115 							 insert_list, remap_list);
2116 				if (r)
2117 					goto out;
2118 			}
2119 			if (node->last > last) {
2120 				pr_debug("change old range last\n");
2121 				r = svm_range_split_tail(prange, last,
2122 							 insert_list, remap_list);
2123 				if (r)
2124 					goto out;
2125 			}
2126 		} else {
2127 			/* The node is contained within start..last,
2128 			 * just update it
2129 			 */
2130 			list_add(&prange->update_list, update_list);
2131 		}
2132 
2133 		/* insert a new node if needed */
2134 		if (node->start > start) {
2135 			r = svm_range_split_new(svms, start, node->start - 1,
2136 						READ_ONCE(max_svm_range_pages),
2137 						&new_list, update_list);
2138 			if (r)
2139 				goto out;
2140 		}
2141 
2142 		node = next;
2143 		start = next_start;
2144 	}
2145 
2146 	/* add a final range at the end if needed */
2147 	if (start <= last)
2148 		r = svm_range_split_new(svms, start, last,
2149 					READ_ONCE(max_svm_range_pages),
2150 					&new_list, update_list);
2151 
2152 out:
2153 	if (r) {
2154 		list_for_each_entry_safe(prange, tmp, insert_list, list)
2155 			svm_range_free(prange, false);
2156 		list_for_each_entry_safe(prange, tmp, &new_list, list)
2157 			svm_range_free(prange, true);
2158 	} else {
2159 		list_splice(&new_list, insert_list);
2160 	}
2161 
2162 	return r;
2163 }
2164 
2165 static void
2166 svm_range_update_notifier_and_interval_tree(struct mm_struct *mm,
2167 					    struct svm_range *prange)
2168 {
2169 	unsigned long start;
2170 	unsigned long last;
2171 
2172 	start = prange->notifier.interval_tree.start >> PAGE_SHIFT;
2173 	last = prange->notifier.interval_tree.last >> PAGE_SHIFT;
2174 
2175 	if (prange->start == start && prange->last == last)
2176 		return;
2177 
2178 	pr_debug("up notifier 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
2179 		  prange->svms, prange, start, last, prange->start,
2180 		  prange->last);
2181 
2182 	if (start != 0 && last != 0) {
2183 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
2184 		svm_range_remove_notifier(prange);
2185 	}
2186 	prange->it_node.start = prange->start;
2187 	prange->it_node.last = prange->last;
2188 
2189 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
2190 	svm_range_add_notifier_locked(mm, prange);
2191 }
2192 
2193 static void
2194 svm_range_handle_list_op(struct svm_range_list *svms, struct svm_range *prange,
2195 			 struct mm_struct *mm)
2196 {
2197 	switch (prange->work_item.op) {
2198 	case SVM_OP_NULL:
2199 		pr_debug("NULL OP 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2200 			 svms, prange, prange->start, prange->last);
2201 		break;
2202 	case SVM_OP_UNMAP_RANGE:
2203 		pr_debug("remove 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2204 			 svms, prange, prange->start, prange->last);
2205 		svm_range_unlink(prange);
2206 		svm_range_remove_notifier(prange);
2207 		svm_range_free(prange, true);
2208 		break;
2209 	case SVM_OP_UPDATE_RANGE_NOTIFIER:
2210 		pr_debug("update notifier 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2211 			 svms, prange, prange->start, prange->last);
2212 		svm_range_update_notifier_and_interval_tree(mm, prange);
2213 		break;
2214 	case SVM_OP_UPDATE_RANGE_NOTIFIER_AND_MAP:
2215 		pr_debug("update and map 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2216 			 svms, prange, prange->start, prange->last);
2217 		svm_range_update_notifier_and_interval_tree(mm, prange);
2218 		/* TODO: implement deferred validation and mapping */
2219 		break;
2220 	case SVM_OP_ADD_RANGE:
2221 		pr_debug("add 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms, prange,
2222 			 prange->start, prange->last);
2223 		svm_range_add_to_svms(prange);
2224 		svm_range_add_notifier_locked(mm, prange);
2225 		break;
2226 	case SVM_OP_ADD_RANGE_AND_MAP:
2227 		pr_debug("add and map 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms,
2228 			 prange, prange->start, prange->last);
2229 		svm_range_add_to_svms(prange);
2230 		svm_range_add_notifier_locked(mm, prange);
2231 		/* TODO: implement deferred validation and mapping */
2232 		break;
2233 	default:
2234 		WARN_ONCE(1, "Unknown prange 0x%p work op %d\n", prange,
2235 			 prange->work_item.op);
2236 	}
2237 }
2238 
2239 static void svm_range_drain_retry_fault(struct svm_range_list *svms)
2240 {
2241 	struct kfd_process_device *pdd;
2242 	struct kfd_process *p;
2243 	int drain;
2244 	uint32_t i;
2245 
2246 	p = container_of(svms, struct kfd_process, svms);
2247 
2248 restart:
2249 	drain = atomic_read(&svms->drain_pagefaults);
2250 	if (!drain)
2251 		return;
2252 
2253 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2254 		pdd = p->pdds[i];
2255 		if (!pdd)
2256 			continue;
2257 
2258 		pr_debug("drain retry fault gpu %d svms %p\n", i, svms);
2259 
2260 		amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2261 				pdd->dev->adev->irq.retry_cam_enabled ?
2262 				&pdd->dev->adev->irq.ih :
2263 				&pdd->dev->adev->irq.ih1);
2264 
2265 		if (pdd->dev->adev->irq.retry_cam_enabled)
2266 			amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2267 				&pdd->dev->adev->irq.ih_soft);
2268 
2269 
2270 		pr_debug("drain retry fault gpu %d svms 0x%p done\n", i, svms);
2271 	}
2272 	if (atomic_cmpxchg(&svms->drain_pagefaults, drain, 0) != drain)
2273 		goto restart;
2274 }
2275 
2276 static void svm_range_deferred_list_work(struct work_struct *work)
2277 {
2278 	struct svm_range_list *svms;
2279 	struct svm_range *prange;
2280 	struct mm_struct *mm;
2281 
2282 	svms = container_of(work, struct svm_range_list, deferred_list_work);
2283 	pr_debug("enter svms 0x%p\n", svms);
2284 
2285 	spin_lock(&svms->deferred_list_lock);
2286 	while (!list_empty(&svms->deferred_range_list)) {
2287 		prange = list_first_entry(&svms->deferred_range_list,
2288 					  struct svm_range, deferred_list);
2289 		spin_unlock(&svms->deferred_list_lock);
2290 
2291 		pr_debug("prange 0x%p [0x%lx 0x%lx] op %d\n", prange,
2292 			 prange->start, prange->last, prange->work_item.op);
2293 
2294 		mm = prange->work_item.mm;
2295 retry:
2296 		mmap_write_lock(mm);
2297 
2298 		/* Checking for the need to drain retry faults must be inside
2299 		 * mmap write lock to serialize with munmap notifiers.
2300 		 */
2301 		if (unlikely(atomic_read(&svms->drain_pagefaults))) {
2302 			mmap_write_unlock(mm);
2303 			svm_range_drain_retry_fault(svms);
2304 			goto retry;
2305 		}
2306 
2307 		/* Remove from deferred_list must be inside mmap write lock, for
2308 		 * two race cases:
2309 		 * 1. unmap_from_cpu may change work_item.op and add the range
2310 		 *    to deferred_list again, cause use after free bug.
2311 		 * 2. svm_range_list_lock_and_flush_work may hold mmap write
2312 		 *    lock and continue because deferred_list is empty, but
2313 		 *    deferred_list work is actually waiting for mmap lock.
2314 		 */
2315 		spin_lock(&svms->deferred_list_lock);
2316 		list_del_init(&prange->deferred_list);
2317 		spin_unlock(&svms->deferred_list_lock);
2318 
2319 		mutex_lock(&svms->lock);
2320 		mutex_lock(&prange->migrate_mutex);
2321 		while (!list_empty(&prange->child_list)) {
2322 			struct svm_range *pchild;
2323 
2324 			pchild = list_first_entry(&prange->child_list,
2325 						struct svm_range, child_list);
2326 			pr_debug("child prange 0x%p op %d\n", pchild,
2327 				 pchild->work_item.op);
2328 			list_del_init(&pchild->child_list);
2329 			svm_range_handle_list_op(svms, pchild, mm);
2330 		}
2331 		mutex_unlock(&prange->migrate_mutex);
2332 
2333 		svm_range_handle_list_op(svms, prange, mm);
2334 		mutex_unlock(&svms->lock);
2335 		mmap_write_unlock(mm);
2336 
2337 		/* Pairs with mmget in svm_range_add_list_work */
2338 		mmput(mm);
2339 
2340 		spin_lock(&svms->deferred_list_lock);
2341 	}
2342 	spin_unlock(&svms->deferred_list_lock);
2343 	pr_debug("exit svms 0x%p\n", svms);
2344 }
2345 
2346 void
2347 svm_range_add_list_work(struct svm_range_list *svms, struct svm_range *prange,
2348 			struct mm_struct *mm, enum svm_work_list_ops op)
2349 {
2350 	spin_lock(&svms->deferred_list_lock);
2351 	/* if prange is on the deferred list */
2352 	if (!list_empty(&prange->deferred_list)) {
2353 		pr_debug("update exist prange 0x%p work op %d\n", prange, op);
2354 		WARN_ONCE(prange->work_item.mm != mm, "unmatch mm\n");
2355 		if (op != SVM_OP_NULL &&
2356 		    prange->work_item.op != SVM_OP_UNMAP_RANGE)
2357 			prange->work_item.op = op;
2358 	} else {
2359 		prange->work_item.op = op;
2360 
2361 		/* Pairs with mmput in deferred_list_work */
2362 		mmget(mm);
2363 		prange->work_item.mm = mm;
2364 		list_add_tail(&prange->deferred_list,
2365 			      &prange->svms->deferred_range_list);
2366 		pr_debug("add prange 0x%p [0x%lx 0x%lx] to work list op %d\n",
2367 			 prange, prange->start, prange->last, op);
2368 	}
2369 	spin_unlock(&svms->deferred_list_lock);
2370 }
2371 
2372 void schedule_deferred_list_work(struct svm_range_list *svms)
2373 {
2374 	spin_lock(&svms->deferred_list_lock);
2375 	if (!list_empty(&svms->deferred_range_list))
2376 		schedule_work(&svms->deferred_list_work);
2377 	spin_unlock(&svms->deferred_list_lock);
2378 }
2379 
2380 static void
2381 svm_range_unmap_split(struct mm_struct *mm, struct svm_range *parent,
2382 		      struct svm_range *prange, unsigned long start,
2383 		      unsigned long last)
2384 {
2385 	struct svm_range *head;
2386 	struct svm_range *tail;
2387 
2388 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2389 		pr_debug("prange 0x%p [0x%lx 0x%lx] is already freed\n", prange,
2390 			 prange->start, prange->last);
2391 		return;
2392 	}
2393 	if (start > prange->last || last < prange->start)
2394 		return;
2395 
2396 	head = tail = prange;
2397 	if (start > prange->start)
2398 		svm_range_split(prange, prange->start, start - 1, &tail);
2399 	if (last < tail->last)
2400 		svm_range_split(tail, last + 1, tail->last, &head);
2401 
2402 	if (head != prange && tail != prange) {
2403 		svm_range_add_child(parent, mm, head, SVM_OP_UNMAP_RANGE);
2404 		svm_range_add_child(parent, mm, tail, SVM_OP_ADD_RANGE);
2405 	} else if (tail != prange) {
2406 		svm_range_add_child(parent, mm, tail, SVM_OP_UNMAP_RANGE);
2407 	} else if (head != prange) {
2408 		svm_range_add_child(parent, mm, head, SVM_OP_UNMAP_RANGE);
2409 	} else if (parent != prange) {
2410 		prange->work_item.op = SVM_OP_UNMAP_RANGE;
2411 	}
2412 }
2413 
2414 static void
2415 svm_range_unmap_from_cpu(struct mm_struct *mm, struct svm_range *prange,
2416 			 unsigned long start, unsigned long last)
2417 {
2418 	uint32_t trigger = KFD_SVM_UNMAP_TRIGGER_UNMAP_FROM_CPU;
2419 	struct svm_range_list *svms;
2420 	struct svm_range *pchild;
2421 	struct kfd_process *p;
2422 	unsigned long s, l;
2423 	bool unmap_parent;
2424 
2425 	p = kfd_lookup_process_by_mm(mm);
2426 	if (!p)
2427 		return;
2428 	svms = &p->svms;
2429 
2430 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n", svms,
2431 		 prange, prange->start, prange->last, start, last);
2432 
2433 	/* Make sure pending page faults are drained in the deferred worker
2434 	 * before the range is freed to avoid straggler interrupts on
2435 	 * unmapped memory causing "phantom faults".
2436 	 */
2437 	atomic_inc(&svms->drain_pagefaults);
2438 
2439 	unmap_parent = start <= prange->start && last >= prange->last;
2440 
2441 	list_for_each_entry(pchild, &prange->child_list, child_list) {
2442 		mutex_lock_nested(&pchild->lock, 1);
2443 		s = max(start, pchild->start);
2444 		l = min(last, pchild->last);
2445 		if (l >= s)
2446 			svm_range_unmap_from_gpus(pchild, s, l, trigger);
2447 		svm_range_unmap_split(mm, prange, pchild, start, last);
2448 		mutex_unlock(&pchild->lock);
2449 	}
2450 	s = max(start, prange->start);
2451 	l = min(last, prange->last);
2452 	if (l >= s)
2453 		svm_range_unmap_from_gpus(prange, s, l, trigger);
2454 	svm_range_unmap_split(mm, prange, prange, start, last);
2455 
2456 	if (unmap_parent)
2457 		svm_range_add_list_work(svms, prange, mm, SVM_OP_UNMAP_RANGE);
2458 	else
2459 		svm_range_add_list_work(svms, prange, mm,
2460 					SVM_OP_UPDATE_RANGE_NOTIFIER);
2461 	schedule_deferred_list_work(svms);
2462 
2463 	kfd_unref_process(p);
2464 }
2465 
2466 /**
2467  * svm_range_cpu_invalidate_pagetables - interval notifier callback
2468  * @mni: mmu_interval_notifier struct
2469  * @range: mmu_notifier_range struct
2470  * @cur_seq: value to pass to mmu_interval_set_seq()
2471  *
2472  * If event is MMU_NOTIFY_UNMAP, this is from CPU unmap range, otherwise, it
2473  * is from migration, or CPU page invalidation callback.
2474  *
2475  * For unmap event, unmap range from GPUs, remove prange from svms in a delayed
2476  * work thread, and split prange if only part of prange is unmapped.
2477  *
2478  * For invalidation event, if GPU retry fault is not enabled, evict the queues,
2479  * then schedule svm_range_restore_work to update GPU mapping and resume queues.
2480  * If GPU retry fault is enabled, unmap the svm range from GPU, retry fault will
2481  * update GPU mapping to recover.
2482  *
2483  * Context: mmap lock, notifier_invalidate_start lock are held
2484  *          for invalidate event, prange lock is held if this is from migration
2485  */
2486 static bool
2487 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
2488 				    const struct mmu_notifier_range *range,
2489 				    unsigned long cur_seq)
2490 {
2491 	struct svm_range *prange;
2492 	unsigned long start;
2493 	unsigned long last;
2494 
2495 	if (range->event == MMU_NOTIFY_RELEASE)
2496 		return true;
2497 	if (!mmget_not_zero(mni->mm))
2498 		return true;
2499 
2500 	start = mni->interval_tree.start;
2501 	last = mni->interval_tree.last;
2502 	start = max(start, range->start) >> PAGE_SHIFT;
2503 	last = min(last, range->end - 1) >> PAGE_SHIFT;
2504 	pr_debug("[0x%lx 0x%lx] range[0x%lx 0x%lx] notifier[0x%lx 0x%lx] %d\n",
2505 		 start, last, range->start >> PAGE_SHIFT,
2506 		 (range->end - 1) >> PAGE_SHIFT,
2507 		 mni->interval_tree.start >> PAGE_SHIFT,
2508 		 mni->interval_tree.last >> PAGE_SHIFT, range->event);
2509 
2510 	prange = container_of(mni, struct svm_range, notifier);
2511 
2512 	svm_range_lock(prange);
2513 	mmu_interval_set_seq(mni, cur_seq);
2514 
2515 	switch (range->event) {
2516 	case MMU_NOTIFY_UNMAP:
2517 		svm_range_unmap_from_cpu(mni->mm, prange, start, last);
2518 		break;
2519 	default:
2520 		svm_range_evict(prange, mni->mm, start, last, range->event);
2521 		break;
2522 	}
2523 
2524 	svm_range_unlock(prange);
2525 	mmput(mni->mm);
2526 
2527 	return true;
2528 }
2529 
2530 /**
2531  * svm_range_from_addr - find svm range from fault address
2532  * @svms: svm range list header
2533  * @addr: address to search range interval tree, in pages
2534  * @parent: parent range if range is on child list
2535  *
2536  * Context: The caller must hold svms->lock
2537  *
2538  * Return: the svm_range found or NULL
2539  */
2540 struct svm_range *
2541 svm_range_from_addr(struct svm_range_list *svms, unsigned long addr,
2542 		    struct svm_range **parent)
2543 {
2544 	struct interval_tree_node *node;
2545 	struct svm_range *prange;
2546 	struct svm_range *pchild;
2547 
2548 	node = interval_tree_iter_first(&svms->objects, addr, addr);
2549 	if (!node)
2550 		return NULL;
2551 
2552 	prange = container_of(node, struct svm_range, it_node);
2553 	pr_debug("address 0x%lx prange [0x%lx 0x%lx] node [0x%lx 0x%lx]\n",
2554 		 addr, prange->start, prange->last, node->start, node->last);
2555 
2556 	if (addr >= prange->start && addr <= prange->last) {
2557 		if (parent)
2558 			*parent = prange;
2559 		return prange;
2560 	}
2561 	list_for_each_entry(pchild, &prange->child_list, child_list)
2562 		if (addr >= pchild->start && addr <= pchild->last) {
2563 			pr_debug("found address 0x%lx pchild [0x%lx 0x%lx]\n",
2564 				 addr, pchild->start, pchild->last);
2565 			if (parent)
2566 				*parent = prange;
2567 			return pchild;
2568 		}
2569 
2570 	return NULL;
2571 }
2572 
2573 /* svm_range_best_restore_location - decide the best fault restore location
2574  * @prange: svm range structure
2575  * @adev: the GPU on which vm fault happened
2576  *
2577  * This is only called when xnack is on, to decide the best location to restore
2578  * the range mapping after GPU vm fault. Caller uses the best location to do
2579  * migration if actual loc is not best location, then update GPU page table
2580  * mapping to the best location.
2581  *
2582  * If the preferred loc is accessible by faulting GPU, use preferred loc.
2583  * If vm fault gpu idx is on range ACCESSIBLE bitmap, best_loc is vm fault gpu
2584  * If vm fault gpu idx is on range ACCESSIBLE_IN_PLACE bitmap, then
2585  *    if range actual loc is cpu, best_loc is cpu
2586  *    if vm fault gpu is on xgmi same hive of range actual loc gpu, best_loc is
2587  *    range actual loc.
2588  * Otherwise, GPU no access, best_loc is -1.
2589  *
2590  * Return:
2591  * -1 means vm fault GPU no access
2592  * 0 for CPU or GPU id
2593  */
2594 static int32_t
2595 svm_range_best_restore_location(struct svm_range *prange,
2596 				struct kfd_node *node,
2597 				int32_t *gpuidx)
2598 {
2599 	struct kfd_node *bo_node, *preferred_node;
2600 	struct kfd_process *p;
2601 	uint32_t gpuid;
2602 	int r;
2603 
2604 	p = container_of(prange->svms, struct kfd_process, svms);
2605 
2606 	r = kfd_process_gpuid_from_node(p, node, &gpuid, gpuidx);
2607 	if (r < 0) {
2608 		pr_debug("failed to get gpuid from kgd\n");
2609 		return -1;
2610 	}
2611 
2612 	if (node->adev->gmc.is_app_apu)
2613 		return 0;
2614 
2615 	if (prange->preferred_loc == gpuid ||
2616 	    prange->preferred_loc == KFD_IOCTL_SVM_LOCATION_SYSMEM) {
2617 		return prange->preferred_loc;
2618 	} else if (prange->preferred_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
2619 		preferred_node = svm_range_get_node_by_id(prange, prange->preferred_loc);
2620 		if (preferred_node && svm_nodes_in_same_hive(node, preferred_node))
2621 			return prange->preferred_loc;
2622 		/* fall through */
2623 	}
2624 
2625 	if (test_bit(*gpuidx, prange->bitmap_access))
2626 		return gpuid;
2627 
2628 	if (test_bit(*gpuidx, prange->bitmap_aip)) {
2629 		if (!prange->actual_loc)
2630 			return 0;
2631 
2632 		bo_node = svm_range_get_node_by_id(prange, prange->actual_loc);
2633 		if (bo_node && svm_nodes_in_same_hive(node, bo_node))
2634 			return prange->actual_loc;
2635 		else
2636 			return 0;
2637 	}
2638 
2639 	return -1;
2640 }
2641 
2642 static int
2643 svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
2644 			       unsigned long *start, unsigned long *last,
2645 			       bool *is_heap_stack)
2646 {
2647 	struct vm_area_struct *vma;
2648 	struct interval_tree_node *node;
2649 	unsigned long start_limit, end_limit;
2650 
2651 	vma = vma_lookup(p->mm, addr << PAGE_SHIFT);
2652 	if (!vma) {
2653 		pr_debug("VMA does not exist in address [0x%llx]\n", addr);
2654 		return -EFAULT;
2655 	}
2656 
2657 	*is_heap_stack = vma_is_initial_heap(vma) || vma_is_initial_stack(vma);
2658 
2659 	start_limit = max(vma->vm_start >> PAGE_SHIFT,
2660 		      (unsigned long)ALIGN_DOWN(addr, 2UL << 8));
2661 	end_limit = min(vma->vm_end >> PAGE_SHIFT,
2662 		    (unsigned long)ALIGN(addr + 1, 2UL << 8));
2663 	/* First range that starts after the fault address */
2664 	node = interval_tree_iter_first(&p->svms.objects, addr + 1, ULONG_MAX);
2665 	if (node) {
2666 		end_limit = min(end_limit, node->start);
2667 		/* Last range that ends before the fault address */
2668 		node = container_of(rb_prev(&node->rb),
2669 				    struct interval_tree_node, rb);
2670 	} else {
2671 		/* Last range must end before addr because
2672 		 * there was no range after addr
2673 		 */
2674 		node = container_of(rb_last(&p->svms.objects.rb_root),
2675 				    struct interval_tree_node, rb);
2676 	}
2677 	if (node) {
2678 		if (node->last >= addr) {
2679 			WARN(1, "Overlap with prev node and page fault addr\n");
2680 			return -EFAULT;
2681 		}
2682 		start_limit = max(start_limit, node->last + 1);
2683 	}
2684 
2685 	*start = start_limit;
2686 	*last = end_limit - 1;
2687 
2688 	pr_debug("vma [0x%lx 0x%lx] range [0x%lx 0x%lx] is_heap_stack %d\n",
2689 		 vma->vm_start >> PAGE_SHIFT, vma->vm_end >> PAGE_SHIFT,
2690 		 *start, *last, *is_heap_stack);
2691 
2692 	return 0;
2693 }
2694 
2695 static int
2696 svm_range_check_vm_userptr(struct kfd_process *p, uint64_t start, uint64_t last,
2697 			   uint64_t *bo_s, uint64_t *bo_l)
2698 {
2699 	struct amdgpu_bo_va_mapping *mapping;
2700 	struct interval_tree_node *node;
2701 	struct amdgpu_bo *bo = NULL;
2702 	unsigned long userptr;
2703 	uint32_t i;
2704 	int r;
2705 
2706 	for (i = 0; i < p->n_pdds; i++) {
2707 		struct amdgpu_vm *vm;
2708 
2709 		if (!p->pdds[i]->drm_priv)
2710 			continue;
2711 
2712 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
2713 		r = amdgpu_bo_reserve(vm->root.bo, false);
2714 		if (r)
2715 			return r;
2716 
2717 		/* Check userptr by searching entire vm->va interval tree */
2718 		node = interval_tree_iter_first(&vm->va, 0, ~0ULL);
2719 		while (node) {
2720 			mapping = container_of((struct rb_node *)node,
2721 					       struct amdgpu_bo_va_mapping, rb);
2722 			bo = mapping->bo_va->base.bo;
2723 
2724 			if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm,
2725 							 start << PAGE_SHIFT,
2726 							 last << PAGE_SHIFT,
2727 							 &userptr)) {
2728 				node = interval_tree_iter_next(node, 0, ~0ULL);
2729 				continue;
2730 			}
2731 
2732 			pr_debug("[0x%llx 0x%llx] already userptr mapped\n",
2733 				 start, last);
2734 			if (bo_s && bo_l) {
2735 				*bo_s = userptr >> PAGE_SHIFT;
2736 				*bo_l = *bo_s + bo->tbo.ttm->num_pages - 1;
2737 			}
2738 			amdgpu_bo_unreserve(vm->root.bo);
2739 			return -EADDRINUSE;
2740 		}
2741 		amdgpu_bo_unreserve(vm->root.bo);
2742 	}
2743 	return 0;
2744 }
2745 
2746 static struct
2747 svm_range *svm_range_create_unregistered_range(struct kfd_node *node,
2748 						struct kfd_process *p,
2749 						struct mm_struct *mm,
2750 						int64_t addr)
2751 {
2752 	struct svm_range *prange = NULL;
2753 	unsigned long start, last;
2754 	uint32_t gpuid, gpuidx;
2755 	bool is_heap_stack;
2756 	uint64_t bo_s = 0;
2757 	uint64_t bo_l = 0;
2758 	int r;
2759 
2760 	if (svm_range_get_range_boundaries(p, addr, &start, &last,
2761 					   &is_heap_stack))
2762 		return NULL;
2763 
2764 	r = svm_range_check_vm(p, start, last, &bo_s, &bo_l);
2765 	if (r != -EADDRINUSE)
2766 		r = svm_range_check_vm_userptr(p, start, last, &bo_s, &bo_l);
2767 
2768 	if (r == -EADDRINUSE) {
2769 		if (addr >= bo_s && addr <= bo_l)
2770 			return NULL;
2771 
2772 		/* Create one page svm range if 2MB range overlapping */
2773 		start = addr;
2774 		last = addr;
2775 	}
2776 
2777 	prange = svm_range_new(&p->svms, start, last, true);
2778 	if (!prange) {
2779 		pr_debug("Failed to create prange in address [0x%llx]\n", addr);
2780 		return NULL;
2781 	}
2782 	if (kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx)) {
2783 		pr_debug("failed to get gpuid from kgd\n");
2784 		svm_range_free(prange, true);
2785 		return NULL;
2786 	}
2787 
2788 	if (is_heap_stack)
2789 		prange->preferred_loc = KFD_IOCTL_SVM_LOCATION_SYSMEM;
2790 
2791 	svm_range_add_to_svms(prange);
2792 	svm_range_add_notifier_locked(mm, prange);
2793 
2794 	return prange;
2795 }
2796 
2797 /* svm_range_skip_recover - decide if prange can be recovered
2798  * @prange: svm range structure
2799  *
2800  * GPU vm retry fault handle skip recover the range for cases:
2801  * 1. prange is on deferred list to be removed after unmap, it is stale fault,
2802  *    deferred list work will drain the stale fault before free the prange.
2803  * 2. prange is on deferred list to add interval notifier after split, or
2804  * 3. prange is child range, it is split from parent prange, recover later
2805  *    after interval notifier is added.
2806  *
2807  * Return: true to skip recover, false to recover
2808  */
2809 static bool svm_range_skip_recover(struct svm_range *prange)
2810 {
2811 	struct svm_range_list *svms = prange->svms;
2812 
2813 	spin_lock(&svms->deferred_list_lock);
2814 	if (list_empty(&prange->deferred_list) &&
2815 	    list_empty(&prange->child_list)) {
2816 		spin_unlock(&svms->deferred_list_lock);
2817 		return false;
2818 	}
2819 	spin_unlock(&svms->deferred_list_lock);
2820 
2821 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2822 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] unmapped\n",
2823 			 svms, prange, prange->start, prange->last);
2824 		return true;
2825 	}
2826 	if (prange->work_item.op == SVM_OP_ADD_RANGE_AND_MAP ||
2827 	    prange->work_item.op == SVM_OP_ADD_RANGE) {
2828 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] not added yet\n",
2829 			 svms, prange, prange->start, prange->last);
2830 		return true;
2831 	}
2832 	return false;
2833 }
2834 
2835 static void
2836 svm_range_count_fault(struct kfd_node *node, struct kfd_process *p,
2837 		      int32_t gpuidx)
2838 {
2839 	struct kfd_process_device *pdd;
2840 
2841 	/* fault is on different page of same range
2842 	 * or fault is skipped to recover later
2843 	 * or fault is on invalid virtual address
2844 	 */
2845 	if (gpuidx == MAX_GPU_INSTANCE) {
2846 		uint32_t gpuid;
2847 		int r;
2848 
2849 		r = kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx);
2850 		if (r < 0)
2851 			return;
2852 	}
2853 
2854 	/* fault is recovered
2855 	 * or fault cannot recover because GPU no access on the range
2856 	 */
2857 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
2858 	if (pdd)
2859 		WRITE_ONCE(pdd->faults, pdd->faults + 1);
2860 }
2861 
2862 static bool
2863 svm_fault_allowed(struct vm_area_struct *vma, bool write_fault)
2864 {
2865 	unsigned long requested = VM_READ;
2866 
2867 	if (write_fault)
2868 		requested |= VM_WRITE;
2869 
2870 	pr_debug("requested 0x%lx, vma permission flags 0x%lx\n", requested,
2871 		vma->vm_flags);
2872 	return (vma->vm_flags & requested) == requested;
2873 }
2874 
2875 int
2876 svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
2877 			uint32_t vmid, uint32_t node_id,
2878 			uint64_t addr, bool write_fault)
2879 {
2880 	unsigned long start, last, size;
2881 	struct mm_struct *mm = NULL;
2882 	struct svm_range_list *svms;
2883 	struct svm_range *prange;
2884 	struct kfd_process *p;
2885 	ktime_t timestamp = ktime_get_boottime();
2886 	struct kfd_node *node;
2887 	int32_t best_loc;
2888 	int32_t gpuidx = MAX_GPU_INSTANCE;
2889 	bool write_locked = false;
2890 	struct vm_area_struct *vma;
2891 	bool migration = false;
2892 	int r = 0;
2893 
2894 	if (!KFD_IS_SVM_API_SUPPORTED(adev)) {
2895 		pr_debug("device does not support SVM\n");
2896 		return -EFAULT;
2897 	}
2898 
2899 	p = kfd_lookup_process_by_pasid(pasid);
2900 	if (!p) {
2901 		pr_debug("kfd process not founded pasid 0x%x\n", pasid);
2902 		return 0;
2903 	}
2904 	svms = &p->svms;
2905 
2906 	pr_debug("restoring svms 0x%p fault address 0x%llx\n", svms, addr);
2907 
2908 	if (atomic_read(&svms->drain_pagefaults)) {
2909 		pr_debug("draining retry fault, drop fault 0x%llx\n", addr);
2910 		r = 0;
2911 		goto out;
2912 	}
2913 
2914 	if (!p->xnack_enabled) {
2915 		pr_debug("XNACK not enabled for pasid 0x%x\n", pasid);
2916 		r = -EFAULT;
2917 		goto out;
2918 	}
2919 
2920 	/* p->lead_thread is available as kfd_process_wq_release flush the work
2921 	 * before releasing task ref.
2922 	 */
2923 	mm = get_task_mm(p->lead_thread);
2924 	if (!mm) {
2925 		pr_debug("svms 0x%p failed to get mm\n", svms);
2926 		r = 0;
2927 		goto out;
2928 	}
2929 
2930 	node = kfd_node_by_irq_ids(adev, node_id, vmid);
2931 	if (!node) {
2932 		pr_debug("kfd node does not exist node_id: %d, vmid: %d\n", node_id,
2933 			 vmid);
2934 		r = -EFAULT;
2935 		goto out;
2936 	}
2937 	mmap_read_lock(mm);
2938 retry_write_locked:
2939 	mutex_lock(&svms->lock);
2940 	prange = svm_range_from_addr(svms, addr, NULL);
2941 	if (!prange) {
2942 		pr_debug("failed to find prange svms 0x%p address [0x%llx]\n",
2943 			 svms, addr);
2944 		if (!write_locked) {
2945 			/* Need the write lock to create new range with MMU notifier.
2946 			 * Also flush pending deferred work to make sure the interval
2947 			 * tree is up to date before we add a new range
2948 			 */
2949 			mutex_unlock(&svms->lock);
2950 			mmap_read_unlock(mm);
2951 			mmap_write_lock(mm);
2952 			write_locked = true;
2953 			goto retry_write_locked;
2954 		}
2955 		prange = svm_range_create_unregistered_range(node, p, mm, addr);
2956 		if (!prange) {
2957 			pr_debug("failed to create unregistered range svms 0x%p address [0x%llx]\n",
2958 				 svms, addr);
2959 			mmap_write_downgrade(mm);
2960 			r = -EFAULT;
2961 			goto out_unlock_svms;
2962 		}
2963 	}
2964 	if (write_locked)
2965 		mmap_write_downgrade(mm);
2966 
2967 	mutex_lock(&prange->migrate_mutex);
2968 
2969 	if (svm_range_skip_recover(prange)) {
2970 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
2971 		r = 0;
2972 		goto out_unlock_range;
2973 	}
2974 
2975 	/* skip duplicate vm fault on different pages of same range */
2976 	if (ktime_before(timestamp, ktime_add_ns(prange->validate_timestamp,
2977 				AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING))) {
2978 		pr_debug("svms 0x%p [0x%lx %lx] already restored\n",
2979 			 svms, prange->start, prange->last);
2980 		r = 0;
2981 		goto out_unlock_range;
2982 	}
2983 
2984 	/* __do_munmap removed VMA, return success as we are handling stale
2985 	 * retry fault.
2986 	 */
2987 	vma = vma_lookup(mm, addr << PAGE_SHIFT);
2988 	if (!vma) {
2989 		pr_debug("address 0x%llx VMA is removed\n", addr);
2990 		r = 0;
2991 		goto out_unlock_range;
2992 	}
2993 
2994 	if (!svm_fault_allowed(vma, write_fault)) {
2995 		pr_debug("fault addr 0x%llx no %s permission\n", addr,
2996 			write_fault ? "write" : "read");
2997 		r = -EPERM;
2998 		goto out_unlock_range;
2999 	}
3000 
3001 	best_loc = svm_range_best_restore_location(prange, node, &gpuidx);
3002 	if (best_loc == -1) {
3003 		pr_debug("svms %p failed get best restore loc [0x%lx 0x%lx]\n",
3004 			 svms, prange->start, prange->last);
3005 		r = -EACCES;
3006 		goto out_unlock_range;
3007 	}
3008 
3009 	pr_debug("svms %p [0x%lx 0x%lx] best restore 0x%x, actual loc 0x%x\n",
3010 		 svms, prange->start, prange->last, best_loc,
3011 		 prange->actual_loc);
3012 
3013 	kfd_smi_event_page_fault_start(node, p->lead_thread->pid, addr,
3014 				       write_fault, timestamp);
3015 
3016 	if (prange->actual_loc != 0 || best_loc != 0) {
3017 		migration = true;
3018 		/* Align migration range start and size to granularity size */
3019 		size = 1UL << prange->granularity;
3020 		start = max_t(unsigned long, ALIGN_DOWN(addr, size), prange->start);
3021 		last = min_t(unsigned long, ALIGN(addr + 1, size) - 1, prange->last);
3022 
3023 		if (best_loc) {
3024 			r = svm_migrate_to_vram(prange, best_loc, start, last,
3025 					mm, KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU);
3026 			if (r) {
3027 				pr_debug("svm_migrate_to_vram failed (%d) at %llx, falling back to system memory\n",
3028 					 r, addr);
3029 				/* Fallback to system memory if migration to
3030 				 * VRAM failed
3031 				 */
3032 				if (prange->actual_loc && prange->actual_loc != best_loc)
3033 					r = svm_migrate_vram_to_ram(prange, mm, start, last,
3034 						KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU, NULL);
3035 				else
3036 					r = 0;
3037 			}
3038 		} else {
3039 			r = svm_migrate_vram_to_ram(prange, mm, start, last,
3040 					KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU, NULL);
3041 		}
3042 		if (r) {
3043 			pr_debug("failed %d to migrate svms %p [0x%lx 0x%lx]\n",
3044 				 r, svms, start, last);
3045 			goto out_unlock_range;
3046 		}
3047 	}
3048 
3049 	r = svm_range_validate_and_map(mm, prange, gpuidx, false, false, false);
3050 	if (r)
3051 		pr_debug("failed %d to map svms 0x%p [0x%lx 0x%lx] to gpus\n",
3052 			 r, svms, prange->start, prange->last);
3053 
3054 	kfd_smi_event_page_fault_end(node, p->lead_thread->pid, addr,
3055 				     migration);
3056 
3057 out_unlock_range:
3058 	mutex_unlock(&prange->migrate_mutex);
3059 out_unlock_svms:
3060 	mutex_unlock(&svms->lock);
3061 	mmap_read_unlock(mm);
3062 
3063 	svm_range_count_fault(node, p, gpuidx);
3064 
3065 	mmput(mm);
3066 out:
3067 	kfd_unref_process(p);
3068 
3069 	if (r == -EAGAIN) {
3070 		pr_debug("recover vm fault later\n");
3071 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
3072 		r = 0;
3073 	}
3074 	return r;
3075 }
3076 
3077 int
3078 svm_range_switch_xnack_reserve_mem(struct kfd_process *p, bool xnack_enabled)
3079 {
3080 	struct svm_range *prange, *pchild;
3081 	uint64_t reserved_size = 0;
3082 	uint64_t size;
3083 	int r = 0;
3084 
3085 	pr_debug("switching xnack from %d to %d\n", p->xnack_enabled, xnack_enabled);
3086 
3087 	mutex_lock(&p->svms.lock);
3088 
3089 	list_for_each_entry(prange, &p->svms.list, list) {
3090 		svm_range_lock(prange);
3091 		list_for_each_entry(pchild, &prange->child_list, child_list) {
3092 			size = (pchild->last - pchild->start + 1) << PAGE_SHIFT;
3093 			if (xnack_enabled) {
3094 				amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3095 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3096 			} else {
3097 				r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3098 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3099 				if (r)
3100 					goto out_unlock;
3101 				reserved_size += size;
3102 			}
3103 		}
3104 
3105 		size = (prange->last - prange->start + 1) << PAGE_SHIFT;
3106 		if (xnack_enabled) {
3107 			amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3108 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3109 		} else {
3110 			r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3111 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3112 			if (r)
3113 				goto out_unlock;
3114 			reserved_size += size;
3115 		}
3116 out_unlock:
3117 		svm_range_unlock(prange);
3118 		if (r)
3119 			break;
3120 	}
3121 
3122 	if (r)
3123 		amdgpu_amdkfd_unreserve_mem_limit(NULL, reserved_size,
3124 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3125 	else
3126 		/* Change xnack mode must be inside svms lock, to avoid race with
3127 		 * svm_range_deferred_list_work unreserve memory in parallel.
3128 		 */
3129 		p->xnack_enabled = xnack_enabled;
3130 
3131 	mutex_unlock(&p->svms.lock);
3132 	return r;
3133 }
3134 
3135 void svm_range_list_fini(struct kfd_process *p)
3136 {
3137 	struct svm_range *prange;
3138 	struct svm_range *next;
3139 
3140 	pr_debug("pasid 0x%x svms 0x%p\n", p->pasid, &p->svms);
3141 
3142 	cancel_delayed_work_sync(&p->svms.restore_work);
3143 
3144 	/* Ensure list work is finished before process is destroyed */
3145 	flush_work(&p->svms.deferred_list_work);
3146 
3147 	/*
3148 	 * Ensure no retry fault comes in afterwards, as page fault handler will
3149 	 * not find kfd process and take mm lock to recover fault.
3150 	 */
3151 	atomic_inc(&p->svms.drain_pagefaults);
3152 	svm_range_drain_retry_fault(&p->svms);
3153 
3154 	list_for_each_entry_safe(prange, next, &p->svms.list, list) {
3155 		svm_range_unlink(prange);
3156 		svm_range_remove_notifier(prange);
3157 		svm_range_free(prange, true);
3158 	}
3159 
3160 	mutex_destroy(&p->svms.lock);
3161 
3162 	pr_debug("pasid 0x%x svms 0x%p done\n", p->pasid, &p->svms);
3163 }
3164 
3165 int svm_range_list_init(struct kfd_process *p)
3166 {
3167 	struct svm_range_list *svms = &p->svms;
3168 	int i;
3169 
3170 	svms->objects = RB_ROOT_CACHED;
3171 	mutex_init(&svms->lock);
3172 	INIT_LIST_HEAD(&svms->list);
3173 	atomic_set(&svms->evicted_ranges, 0);
3174 	atomic_set(&svms->drain_pagefaults, 0);
3175 	INIT_DELAYED_WORK(&svms->restore_work, svm_range_restore_work);
3176 	INIT_WORK(&svms->deferred_list_work, svm_range_deferred_list_work);
3177 	INIT_LIST_HEAD(&svms->deferred_range_list);
3178 	INIT_LIST_HEAD(&svms->criu_svm_metadata_list);
3179 	spin_lock_init(&svms->deferred_list_lock);
3180 
3181 	for (i = 0; i < p->n_pdds; i++)
3182 		if (KFD_IS_SVM_API_SUPPORTED(p->pdds[i]->dev->adev))
3183 			bitmap_set(svms->bitmap_supported, i, 1);
3184 
3185 	return 0;
3186 }
3187 
3188 /**
3189  * svm_range_check_vm - check if virtual address range mapped already
3190  * @p: current kfd_process
3191  * @start: range start address, in pages
3192  * @last: range last address, in pages
3193  * @bo_s: mapping start address in pages if address range already mapped
3194  * @bo_l: mapping last address in pages if address range already mapped
3195  *
3196  * The purpose is to avoid virtual address ranges already allocated by
3197  * kfd_ioctl_alloc_memory_of_gpu ioctl.
3198  * It looks for each pdd in the kfd_process.
3199  *
3200  * Context: Process context
3201  *
3202  * Return 0 - OK, if the range is not mapped.
3203  * Otherwise error code:
3204  * -EADDRINUSE - if address is mapped already by kfd_ioctl_alloc_memory_of_gpu
3205  * -ERESTARTSYS - A wait for the buffer to become unreserved was interrupted by
3206  * a signal. Release all buffer reservations and return to user-space.
3207  */
3208 static int
3209 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
3210 		   uint64_t *bo_s, uint64_t *bo_l)
3211 {
3212 	struct amdgpu_bo_va_mapping *mapping;
3213 	struct interval_tree_node *node;
3214 	uint32_t i;
3215 	int r;
3216 
3217 	for (i = 0; i < p->n_pdds; i++) {
3218 		struct amdgpu_vm *vm;
3219 
3220 		if (!p->pdds[i]->drm_priv)
3221 			continue;
3222 
3223 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
3224 		r = amdgpu_bo_reserve(vm->root.bo, false);
3225 		if (r)
3226 			return r;
3227 
3228 		node = interval_tree_iter_first(&vm->va, start, last);
3229 		if (node) {
3230 			pr_debug("range [0x%llx 0x%llx] already TTM mapped\n",
3231 				 start, last);
3232 			mapping = container_of((struct rb_node *)node,
3233 					       struct amdgpu_bo_va_mapping, rb);
3234 			if (bo_s && bo_l) {
3235 				*bo_s = mapping->start;
3236 				*bo_l = mapping->last;
3237 			}
3238 			amdgpu_bo_unreserve(vm->root.bo);
3239 			return -EADDRINUSE;
3240 		}
3241 		amdgpu_bo_unreserve(vm->root.bo);
3242 	}
3243 
3244 	return 0;
3245 }
3246 
3247 /**
3248  * svm_range_is_valid - check if virtual address range is valid
3249  * @p: current kfd_process
3250  * @start: range start address, in pages
3251  * @size: range size, in pages
3252  *
3253  * Valid virtual address range means it belongs to one or more VMAs
3254  *
3255  * Context: Process context
3256  *
3257  * Return:
3258  *  0 - OK, otherwise error code
3259  */
3260 static int
3261 svm_range_is_valid(struct kfd_process *p, uint64_t start, uint64_t size)
3262 {
3263 	const unsigned long device_vma = VM_IO | VM_PFNMAP | VM_MIXEDMAP;
3264 	struct vm_area_struct *vma;
3265 	unsigned long end;
3266 	unsigned long start_unchg = start;
3267 
3268 	start <<= PAGE_SHIFT;
3269 	end = start + (size << PAGE_SHIFT);
3270 	do {
3271 		vma = vma_lookup(p->mm, start);
3272 		if (!vma || (vma->vm_flags & device_vma))
3273 			return -EFAULT;
3274 		start = min(end, vma->vm_end);
3275 	} while (start < end);
3276 
3277 	return svm_range_check_vm(p, start_unchg, (end - 1) >> PAGE_SHIFT, NULL,
3278 				  NULL);
3279 }
3280 
3281 /**
3282  * svm_range_best_prefetch_location - decide the best prefetch location
3283  * @prange: svm range structure
3284  *
3285  * For xnack off:
3286  * If range map to single GPU, the best prefetch location is prefetch_loc, which
3287  * can be CPU or GPU.
3288  *
3289  * If range is ACCESS or ACCESS_IN_PLACE by mGPUs, only if mGPU connection on
3290  * XGMI same hive, the best prefetch location is prefetch_loc GPU, othervise
3291  * the best prefetch location is always CPU, because GPU can not have coherent
3292  * mapping VRAM of other GPUs even with large-BAR PCIe connection.
3293  *
3294  * For xnack on:
3295  * If range is not ACCESS_IN_PLACE by mGPUs, the best prefetch location is
3296  * prefetch_loc, other GPU access will generate vm fault and trigger migration.
3297  *
3298  * If range is ACCESS_IN_PLACE by mGPUs, only if mGPU connection on XGMI same
3299  * hive, the best prefetch location is prefetch_loc GPU, otherwise the best
3300  * prefetch location is always CPU.
3301  *
3302  * Context: Process context
3303  *
3304  * Return:
3305  * 0 for CPU or GPU id
3306  */
3307 static uint32_t
3308 svm_range_best_prefetch_location(struct svm_range *prange)
3309 {
3310 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
3311 	uint32_t best_loc = prange->prefetch_loc;
3312 	struct kfd_process_device *pdd;
3313 	struct kfd_node *bo_node;
3314 	struct kfd_process *p;
3315 	uint32_t gpuidx;
3316 
3317 	p = container_of(prange->svms, struct kfd_process, svms);
3318 
3319 	if (!best_loc || best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED)
3320 		goto out;
3321 
3322 	bo_node = svm_range_get_node_by_id(prange, best_loc);
3323 	if (!bo_node) {
3324 		WARN_ONCE(1, "failed to get valid kfd node at id%x\n", best_loc);
3325 		best_loc = 0;
3326 		goto out;
3327 	}
3328 
3329 	if (bo_node->adev->gmc.is_app_apu) {
3330 		best_loc = 0;
3331 		goto out;
3332 	}
3333 
3334 	if (p->xnack_enabled)
3335 		bitmap_copy(bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
3336 	else
3337 		bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
3338 			  MAX_GPU_INSTANCE);
3339 
3340 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
3341 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
3342 		if (!pdd) {
3343 			pr_debug("failed to get device by idx 0x%x\n", gpuidx);
3344 			continue;
3345 		}
3346 
3347 		if (pdd->dev->adev == bo_node->adev)
3348 			continue;
3349 
3350 		if (!svm_nodes_in_same_hive(pdd->dev, bo_node)) {
3351 			best_loc = 0;
3352 			break;
3353 		}
3354 	}
3355 
3356 out:
3357 	pr_debug("xnack %d svms 0x%p [0x%lx 0x%lx] best loc 0x%x\n",
3358 		 p->xnack_enabled, &p->svms, prange->start, prange->last,
3359 		 best_loc);
3360 
3361 	return best_loc;
3362 }
3363 
3364 /* svm_range_trigger_migration - start page migration if prefetch loc changed
3365  * @mm: current process mm_struct
3366  * @prange: svm range structure
3367  * @migrated: output, true if migration is triggered
3368  *
3369  * If range perfetch_loc is GPU, actual loc is cpu 0, then migrate the range
3370  * from ram to vram.
3371  * If range prefetch_loc is cpu 0, actual loc is GPU, then migrate the range
3372  * from vram to ram.
3373  *
3374  * If GPU vm fault retry is not enabled, migration interact with MMU notifier
3375  * and restore work:
3376  * 1. migrate_vma_setup invalidate pages, MMU notifier callback svm_range_evict
3377  *    stops all queues, schedule restore work
3378  * 2. svm_range_restore_work wait for migration is done by
3379  *    a. svm_range_validate_vram takes prange->migrate_mutex
3380  *    b. svm_range_validate_ram HMM get pages wait for CPU fault handle returns
3381  * 3. restore work update mappings of GPU, resume all queues.
3382  *
3383  * Context: Process context
3384  *
3385  * Return:
3386  * 0 - OK, otherwise - error code of migration
3387  */
3388 static int
3389 svm_range_trigger_migration(struct mm_struct *mm, struct svm_range *prange,
3390 			    bool *migrated)
3391 {
3392 	uint32_t best_loc;
3393 	int r = 0;
3394 
3395 	*migrated = false;
3396 	best_loc = svm_range_best_prefetch_location(prange);
3397 
3398 	/* when best_loc is a gpu node and same as prange->actual_loc
3399 	 * we still need do migration as prange->actual_loc !=0 does
3400 	 * not mean all pages in prange are vram. hmm migrate will pick
3401 	 * up right pages during migration.
3402 	 */
3403 	if ((best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED) ||
3404 	    (best_loc == 0 && prange->actual_loc == 0))
3405 		return 0;
3406 
3407 	if (!best_loc) {
3408 		r = svm_migrate_vram_to_ram(prange, mm, prange->start, prange->last,
3409 					KFD_MIGRATE_TRIGGER_PREFETCH, NULL);
3410 		*migrated = !r;
3411 		return r;
3412 	}
3413 
3414 	r = svm_migrate_to_vram(prange, best_loc, prange->start, prange->last,
3415 				mm, KFD_MIGRATE_TRIGGER_PREFETCH);
3416 	*migrated = !r;
3417 
3418 	return r;
3419 }
3420 
3421 int svm_range_schedule_evict_svm_bo(struct amdgpu_amdkfd_fence *fence)
3422 {
3423 	if (!fence)
3424 		return -EINVAL;
3425 
3426 	if (dma_fence_is_signaled(&fence->base))
3427 		return 0;
3428 
3429 	if (fence->svm_bo) {
3430 		WRITE_ONCE(fence->svm_bo->evicting, 1);
3431 		schedule_work(&fence->svm_bo->eviction_work);
3432 	}
3433 
3434 	return 0;
3435 }
3436 
3437 static void svm_range_evict_svm_bo_worker(struct work_struct *work)
3438 {
3439 	struct svm_range_bo *svm_bo;
3440 	struct mm_struct *mm;
3441 	int r = 0;
3442 
3443 	svm_bo = container_of(work, struct svm_range_bo, eviction_work);
3444 	if (!svm_bo_ref_unless_zero(svm_bo))
3445 		return; /* svm_bo was freed while eviction was pending */
3446 
3447 	if (mmget_not_zero(svm_bo->eviction_fence->mm)) {
3448 		mm = svm_bo->eviction_fence->mm;
3449 	} else {
3450 		svm_range_bo_unref(svm_bo);
3451 		return;
3452 	}
3453 
3454 	mmap_read_lock(mm);
3455 	spin_lock(&svm_bo->list_lock);
3456 	while (!list_empty(&svm_bo->range_list) && !r) {
3457 		struct svm_range *prange =
3458 				list_first_entry(&svm_bo->range_list,
3459 						struct svm_range, svm_bo_list);
3460 		int retries = 3;
3461 
3462 		list_del_init(&prange->svm_bo_list);
3463 		spin_unlock(&svm_bo->list_lock);
3464 
3465 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
3466 			 prange->start, prange->last);
3467 
3468 		mutex_lock(&prange->migrate_mutex);
3469 		do {
3470 			/* migrate all vram pages in this prange to sys ram
3471 			 * after that prange->actual_loc should be zero
3472 			 */
3473 			r = svm_migrate_vram_to_ram(prange, mm,
3474 					prange->start, prange->last,
3475 					KFD_MIGRATE_TRIGGER_TTM_EVICTION, NULL);
3476 		} while (!r && prange->actual_loc && --retries);
3477 
3478 		if (!r && prange->actual_loc)
3479 			pr_info_once("Migration failed during eviction");
3480 
3481 		if (!prange->actual_loc) {
3482 			mutex_lock(&prange->lock);
3483 			prange->svm_bo = NULL;
3484 			mutex_unlock(&prange->lock);
3485 		}
3486 		mutex_unlock(&prange->migrate_mutex);
3487 
3488 		spin_lock(&svm_bo->list_lock);
3489 	}
3490 	spin_unlock(&svm_bo->list_lock);
3491 	mmap_read_unlock(mm);
3492 	mmput(mm);
3493 
3494 	dma_fence_signal(&svm_bo->eviction_fence->base);
3495 
3496 	/* This is the last reference to svm_bo, after svm_range_vram_node_free
3497 	 * has been called in svm_migrate_vram_to_ram
3498 	 */
3499 	WARN_ONCE(!r && kref_read(&svm_bo->kref) != 1, "This was not the last reference\n");
3500 	svm_range_bo_unref(svm_bo);
3501 }
3502 
3503 static int
3504 svm_range_set_attr(struct kfd_process *p, struct mm_struct *mm,
3505 		   uint64_t start, uint64_t size, uint32_t nattr,
3506 		   struct kfd_ioctl_svm_attribute *attrs)
3507 {
3508 	struct amdkfd_process_info *process_info = p->kgd_process_info;
3509 	struct list_head update_list;
3510 	struct list_head insert_list;
3511 	struct list_head remove_list;
3512 	struct list_head remap_list;
3513 	struct svm_range_list *svms;
3514 	struct svm_range *prange;
3515 	struct svm_range *next;
3516 	bool update_mapping = false;
3517 	bool flush_tlb;
3518 	int r, ret = 0;
3519 
3520 	pr_debug("pasid 0x%x svms 0x%p [0x%llx 0x%llx] pages 0x%llx\n",
3521 		 p->pasid, &p->svms, start, start + size - 1, size);
3522 
3523 	r = svm_range_check_attr(p, nattr, attrs);
3524 	if (r)
3525 		return r;
3526 
3527 	svms = &p->svms;
3528 
3529 	mutex_lock(&process_info->lock);
3530 
3531 	svm_range_list_lock_and_flush_work(svms, mm);
3532 
3533 	r = svm_range_is_valid(p, start, size);
3534 	if (r) {
3535 		pr_debug("invalid range r=%d\n", r);
3536 		mmap_write_unlock(mm);
3537 		goto out;
3538 	}
3539 
3540 	mutex_lock(&svms->lock);
3541 
3542 	/* Add new range and split existing ranges as needed */
3543 	r = svm_range_add(p, start, size, nattr, attrs, &update_list,
3544 			  &insert_list, &remove_list, &remap_list);
3545 	if (r) {
3546 		mutex_unlock(&svms->lock);
3547 		mmap_write_unlock(mm);
3548 		goto out;
3549 	}
3550 	/* Apply changes as a transaction */
3551 	list_for_each_entry_safe(prange, next, &insert_list, list) {
3552 		svm_range_add_to_svms(prange);
3553 		svm_range_add_notifier_locked(mm, prange);
3554 	}
3555 	list_for_each_entry(prange, &update_list, update_list) {
3556 		svm_range_apply_attrs(p, prange, nattr, attrs, &update_mapping);
3557 		/* TODO: unmap ranges from GPU that lost access */
3558 	}
3559 	list_for_each_entry_safe(prange, next, &remove_list, update_list) {
3560 		pr_debug("unlink old 0x%p prange 0x%p [0x%lx 0x%lx]\n",
3561 			 prange->svms, prange, prange->start,
3562 			 prange->last);
3563 		svm_range_unlink(prange);
3564 		svm_range_remove_notifier(prange);
3565 		svm_range_free(prange, false);
3566 	}
3567 
3568 	mmap_write_downgrade(mm);
3569 	/* Trigger migrations and revalidate and map to GPUs as needed. If
3570 	 * this fails we may be left with partially completed actions. There
3571 	 * is no clean way of rolling back to the previous state in such a
3572 	 * case because the rollback wouldn't be guaranteed to work either.
3573 	 */
3574 	list_for_each_entry(prange, &update_list, update_list) {
3575 		bool migrated;
3576 
3577 		mutex_lock(&prange->migrate_mutex);
3578 
3579 		r = svm_range_trigger_migration(mm, prange, &migrated);
3580 		if (r)
3581 			goto out_unlock_range;
3582 
3583 		if (migrated && (!p->xnack_enabled ||
3584 		    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) &&
3585 		    prange->mapped_to_gpu) {
3586 			pr_debug("restore_work will update mappings of GPUs\n");
3587 			mutex_unlock(&prange->migrate_mutex);
3588 			continue;
3589 		}
3590 
3591 		if (!migrated && !update_mapping) {
3592 			mutex_unlock(&prange->migrate_mutex);
3593 			continue;
3594 		}
3595 
3596 		flush_tlb = !migrated && update_mapping && prange->mapped_to_gpu;
3597 
3598 		r = svm_range_validate_and_map(mm, prange, MAX_GPU_INSTANCE,
3599 					       true, true, flush_tlb);
3600 		if (r)
3601 			pr_debug("failed %d to map svm range\n", r);
3602 
3603 out_unlock_range:
3604 		mutex_unlock(&prange->migrate_mutex);
3605 		if (r)
3606 			ret = r;
3607 	}
3608 
3609 	list_for_each_entry(prange, &remap_list, update_list) {
3610 		pr_debug("Remapping prange 0x%p [0x%lx 0x%lx]\n",
3611 			 prange, prange->start, prange->last);
3612 		mutex_lock(&prange->migrate_mutex);
3613 		r = svm_range_validate_and_map(mm, prange, MAX_GPU_INSTANCE,
3614 					       true, true, prange->mapped_to_gpu);
3615 		if (r)
3616 			pr_debug("failed %d on remap svm range\n", r);
3617 		mutex_unlock(&prange->migrate_mutex);
3618 		if (r)
3619 			ret = r;
3620 	}
3621 
3622 	dynamic_svm_range_dump(svms);
3623 
3624 	mutex_unlock(&svms->lock);
3625 	mmap_read_unlock(mm);
3626 out:
3627 	mutex_unlock(&process_info->lock);
3628 
3629 	pr_debug("pasid 0x%x svms 0x%p [0x%llx 0x%llx] done, r=%d\n", p->pasid,
3630 		 &p->svms, start, start + size - 1, r);
3631 
3632 	return ret ? ret : r;
3633 }
3634 
3635 static int
3636 svm_range_get_attr(struct kfd_process *p, struct mm_struct *mm,
3637 		   uint64_t start, uint64_t size, uint32_t nattr,
3638 		   struct kfd_ioctl_svm_attribute *attrs)
3639 {
3640 	DECLARE_BITMAP(bitmap_access, MAX_GPU_INSTANCE);
3641 	DECLARE_BITMAP(bitmap_aip, MAX_GPU_INSTANCE);
3642 	bool get_preferred_loc = false;
3643 	bool get_prefetch_loc = false;
3644 	bool get_granularity = false;
3645 	bool get_accessible = false;
3646 	bool get_flags = false;
3647 	uint64_t last = start + size - 1UL;
3648 	uint8_t granularity = 0xff;
3649 	struct interval_tree_node *node;
3650 	struct svm_range_list *svms;
3651 	struct svm_range *prange;
3652 	uint32_t prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3653 	uint32_t location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3654 	uint32_t flags_and = 0xffffffff;
3655 	uint32_t flags_or = 0;
3656 	int gpuidx;
3657 	uint32_t i;
3658 	int r = 0;
3659 
3660 	pr_debug("svms 0x%p [0x%llx 0x%llx] nattr 0x%x\n", &p->svms, start,
3661 		 start + size - 1, nattr);
3662 
3663 	/* Flush pending deferred work to avoid racing with deferred actions from
3664 	 * previous memory map changes (e.g. munmap). Concurrent memory map changes
3665 	 * can still race with get_attr because we don't hold the mmap lock. But that
3666 	 * would be a race condition in the application anyway, and undefined
3667 	 * behaviour is acceptable in that case.
3668 	 */
3669 	flush_work(&p->svms.deferred_list_work);
3670 
3671 	mmap_read_lock(mm);
3672 	r = svm_range_is_valid(p, start, size);
3673 	mmap_read_unlock(mm);
3674 	if (r) {
3675 		pr_debug("invalid range r=%d\n", r);
3676 		return r;
3677 	}
3678 
3679 	for (i = 0; i < nattr; i++) {
3680 		switch (attrs[i].type) {
3681 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3682 			get_preferred_loc = true;
3683 			break;
3684 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3685 			get_prefetch_loc = true;
3686 			break;
3687 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3688 			get_accessible = true;
3689 			break;
3690 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3691 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3692 			get_flags = true;
3693 			break;
3694 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3695 			get_granularity = true;
3696 			break;
3697 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
3698 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
3699 			fallthrough;
3700 		default:
3701 			pr_debug("get invalid attr type 0x%x\n", attrs[i].type);
3702 			return -EINVAL;
3703 		}
3704 	}
3705 
3706 	svms = &p->svms;
3707 
3708 	mutex_lock(&svms->lock);
3709 
3710 	node = interval_tree_iter_first(&svms->objects, start, last);
3711 	if (!node) {
3712 		pr_debug("range attrs not found return default values\n");
3713 		svm_range_set_default_attributes(&location, &prefetch_loc,
3714 						 &granularity, &flags_and);
3715 		flags_or = flags_and;
3716 		if (p->xnack_enabled)
3717 			bitmap_copy(bitmap_access, svms->bitmap_supported,
3718 				    MAX_GPU_INSTANCE);
3719 		else
3720 			bitmap_zero(bitmap_access, MAX_GPU_INSTANCE);
3721 		bitmap_zero(bitmap_aip, MAX_GPU_INSTANCE);
3722 		goto fill_values;
3723 	}
3724 	bitmap_copy(bitmap_access, svms->bitmap_supported, MAX_GPU_INSTANCE);
3725 	bitmap_copy(bitmap_aip, svms->bitmap_supported, MAX_GPU_INSTANCE);
3726 
3727 	while (node) {
3728 		struct interval_tree_node *next;
3729 
3730 		prange = container_of(node, struct svm_range, it_node);
3731 		next = interval_tree_iter_next(node, start, last);
3732 
3733 		if (get_preferred_loc) {
3734 			if (prange->preferred_loc ==
3735 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3736 			    (location != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3737 			     location != prange->preferred_loc)) {
3738 				location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3739 				get_preferred_loc = false;
3740 			} else {
3741 				location = prange->preferred_loc;
3742 			}
3743 		}
3744 		if (get_prefetch_loc) {
3745 			if (prange->prefetch_loc ==
3746 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3747 			    (prefetch_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3748 			     prefetch_loc != prange->prefetch_loc)) {
3749 				prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3750 				get_prefetch_loc = false;
3751 			} else {
3752 				prefetch_loc = prange->prefetch_loc;
3753 			}
3754 		}
3755 		if (get_accessible) {
3756 			bitmap_and(bitmap_access, bitmap_access,
3757 				   prange->bitmap_access, MAX_GPU_INSTANCE);
3758 			bitmap_and(bitmap_aip, bitmap_aip,
3759 				   prange->bitmap_aip, MAX_GPU_INSTANCE);
3760 		}
3761 		if (get_flags) {
3762 			flags_and &= prange->flags;
3763 			flags_or |= prange->flags;
3764 		}
3765 
3766 		if (get_granularity && prange->granularity < granularity)
3767 			granularity = prange->granularity;
3768 
3769 		node = next;
3770 	}
3771 fill_values:
3772 	mutex_unlock(&svms->lock);
3773 
3774 	for (i = 0; i < nattr; i++) {
3775 		switch (attrs[i].type) {
3776 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3777 			attrs[i].value = location;
3778 			break;
3779 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3780 			attrs[i].value = prefetch_loc;
3781 			break;
3782 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3783 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
3784 							       attrs[i].value);
3785 			if (gpuidx < 0) {
3786 				pr_debug("invalid gpuid %x\n", attrs[i].value);
3787 				return -EINVAL;
3788 			}
3789 			if (test_bit(gpuidx, bitmap_access))
3790 				attrs[i].type = KFD_IOCTL_SVM_ATTR_ACCESS;
3791 			else if (test_bit(gpuidx, bitmap_aip))
3792 				attrs[i].type =
3793 					KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE;
3794 			else
3795 				attrs[i].type = KFD_IOCTL_SVM_ATTR_NO_ACCESS;
3796 			break;
3797 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3798 			attrs[i].value = flags_and;
3799 			break;
3800 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3801 			attrs[i].value = ~flags_or;
3802 			break;
3803 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3804 			attrs[i].value = (uint32_t)granularity;
3805 			break;
3806 		}
3807 	}
3808 
3809 	return 0;
3810 }
3811 
3812 int kfd_criu_resume_svm(struct kfd_process *p)
3813 {
3814 	struct kfd_ioctl_svm_attribute *set_attr_new, *set_attr = NULL;
3815 	int nattr_common = 4, nattr_accessibility = 1;
3816 	struct criu_svm_metadata *criu_svm_md = NULL;
3817 	struct svm_range_list *svms = &p->svms;
3818 	struct criu_svm_metadata *next = NULL;
3819 	uint32_t set_flags = 0xffffffff;
3820 	int i, j, num_attrs, ret = 0;
3821 	uint64_t set_attr_size;
3822 	struct mm_struct *mm;
3823 
3824 	if (list_empty(&svms->criu_svm_metadata_list)) {
3825 		pr_debug("No SVM data from CRIU restore stage 2\n");
3826 		return ret;
3827 	}
3828 
3829 	mm = get_task_mm(p->lead_thread);
3830 	if (!mm) {
3831 		pr_err("failed to get mm for the target process\n");
3832 		return -ESRCH;
3833 	}
3834 
3835 	num_attrs = nattr_common + (nattr_accessibility * p->n_pdds);
3836 
3837 	i = j = 0;
3838 	list_for_each_entry(criu_svm_md, &svms->criu_svm_metadata_list, list) {
3839 		pr_debug("criu_svm_md[%d]\n\tstart: 0x%llx size: 0x%llx (npages)\n",
3840 			 i, criu_svm_md->data.start_addr, criu_svm_md->data.size);
3841 
3842 		for (j = 0; j < num_attrs; j++) {
3843 			pr_debug("\ncriu_svm_md[%d]->attrs[%d].type : 0x%x\ncriu_svm_md[%d]->attrs[%d].value : 0x%x\n",
3844 				 i, j, criu_svm_md->data.attrs[j].type,
3845 				 i, j, criu_svm_md->data.attrs[j].value);
3846 			switch (criu_svm_md->data.attrs[j].type) {
3847 			/* During Checkpoint operation, the query for
3848 			 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC attribute might
3849 			 * return KFD_IOCTL_SVM_LOCATION_UNDEFINED if they were
3850 			 * not used by the range which was checkpointed. Care
3851 			 * must be taken to not restore with an invalid value
3852 			 * otherwise the gpuidx value will be invalid and
3853 			 * set_attr would eventually fail so just replace those
3854 			 * with another dummy attribute such as
3855 			 * KFD_IOCTL_SVM_ATTR_SET_FLAGS.
3856 			 */
3857 			case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3858 				if (criu_svm_md->data.attrs[j].value ==
3859 				    KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
3860 					criu_svm_md->data.attrs[j].type =
3861 						KFD_IOCTL_SVM_ATTR_SET_FLAGS;
3862 					criu_svm_md->data.attrs[j].value = 0;
3863 				}
3864 				break;
3865 			case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3866 				set_flags = criu_svm_md->data.attrs[j].value;
3867 				break;
3868 			default:
3869 				break;
3870 			}
3871 		}
3872 
3873 		/* CLR_FLAGS is not available via get_attr during checkpoint but
3874 		 * it needs to be inserted before restoring the ranges so
3875 		 * allocate extra space for it before calling set_attr
3876 		 */
3877 		set_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
3878 						(num_attrs + 1);
3879 		set_attr_new = krealloc(set_attr, set_attr_size,
3880 					    GFP_KERNEL);
3881 		if (!set_attr_new) {
3882 			ret = -ENOMEM;
3883 			goto exit;
3884 		}
3885 		set_attr = set_attr_new;
3886 
3887 		memcpy(set_attr, criu_svm_md->data.attrs, num_attrs *
3888 					sizeof(struct kfd_ioctl_svm_attribute));
3889 		set_attr[num_attrs].type = KFD_IOCTL_SVM_ATTR_CLR_FLAGS;
3890 		set_attr[num_attrs].value = ~set_flags;
3891 
3892 		ret = svm_range_set_attr(p, mm, criu_svm_md->data.start_addr,
3893 					 criu_svm_md->data.size, num_attrs + 1,
3894 					 set_attr);
3895 		if (ret) {
3896 			pr_err("CRIU: failed to set range attributes\n");
3897 			goto exit;
3898 		}
3899 
3900 		i++;
3901 	}
3902 exit:
3903 	kfree(set_attr);
3904 	list_for_each_entry_safe(criu_svm_md, next, &svms->criu_svm_metadata_list, list) {
3905 		pr_debug("freeing criu_svm_md[]\n\tstart: 0x%llx\n",
3906 						criu_svm_md->data.start_addr);
3907 		kfree(criu_svm_md);
3908 	}
3909 
3910 	mmput(mm);
3911 	return ret;
3912 
3913 }
3914 
3915 int kfd_criu_restore_svm(struct kfd_process *p,
3916 			 uint8_t __user *user_priv_ptr,
3917 			 uint64_t *priv_data_offset,
3918 			 uint64_t max_priv_data_size)
3919 {
3920 	uint64_t svm_priv_data_size, svm_object_md_size, svm_attrs_size;
3921 	int nattr_common = 4, nattr_accessibility = 1;
3922 	struct criu_svm_metadata *criu_svm_md = NULL;
3923 	struct svm_range_list *svms = &p->svms;
3924 	uint32_t num_devices;
3925 	int ret = 0;
3926 
3927 	num_devices = p->n_pdds;
3928 	/* Handle one SVM range object at a time, also the number of gpus are
3929 	 * assumed to be same on the restore node, checking must be done while
3930 	 * evaluating the topology earlier
3931 	 */
3932 
3933 	svm_attrs_size = sizeof(struct kfd_ioctl_svm_attribute) *
3934 		(nattr_common + nattr_accessibility * num_devices);
3935 	svm_object_md_size = sizeof(struct criu_svm_metadata) + svm_attrs_size;
3936 
3937 	svm_priv_data_size = sizeof(struct kfd_criu_svm_range_priv_data) +
3938 								svm_attrs_size;
3939 
3940 	criu_svm_md = kzalloc(svm_object_md_size, GFP_KERNEL);
3941 	if (!criu_svm_md) {
3942 		pr_err("failed to allocate memory to store svm metadata\n");
3943 		return -ENOMEM;
3944 	}
3945 	if (*priv_data_offset + svm_priv_data_size > max_priv_data_size) {
3946 		ret = -EINVAL;
3947 		goto exit;
3948 	}
3949 
3950 	ret = copy_from_user(&criu_svm_md->data, user_priv_ptr + *priv_data_offset,
3951 			     svm_priv_data_size);
3952 	if (ret) {
3953 		ret = -EFAULT;
3954 		goto exit;
3955 	}
3956 	*priv_data_offset += svm_priv_data_size;
3957 
3958 	list_add_tail(&criu_svm_md->list, &svms->criu_svm_metadata_list);
3959 
3960 	return 0;
3961 
3962 
3963 exit:
3964 	kfree(criu_svm_md);
3965 	return ret;
3966 }
3967 
3968 int svm_range_get_info(struct kfd_process *p, uint32_t *num_svm_ranges,
3969 		       uint64_t *svm_priv_data_size)
3970 {
3971 	uint64_t total_size, accessibility_size, common_attr_size;
3972 	int nattr_common = 4, nattr_accessibility = 1;
3973 	int num_devices = p->n_pdds;
3974 	struct svm_range_list *svms;
3975 	struct svm_range *prange;
3976 	uint32_t count = 0;
3977 
3978 	*svm_priv_data_size = 0;
3979 
3980 	svms = &p->svms;
3981 	if (!svms)
3982 		return -EINVAL;
3983 
3984 	mutex_lock(&svms->lock);
3985 	list_for_each_entry(prange, &svms->list, list) {
3986 		pr_debug("prange: 0x%p start: 0x%lx\t npages: 0x%llx\t end: 0x%llx\n",
3987 			 prange, prange->start, prange->npages,
3988 			 prange->start + prange->npages - 1);
3989 		count++;
3990 	}
3991 	mutex_unlock(&svms->lock);
3992 
3993 	*num_svm_ranges = count;
3994 	/* Only the accessbility attributes need to be queried for all the gpus
3995 	 * individually, remaining ones are spanned across the entire process
3996 	 * regardless of the various gpu nodes. Of the remaining attributes,
3997 	 * KFD_IOCTL_SVM_ATTR_CLR_FLAGS need not be saved.
3998 	 *
3999 	 * KFD_IOCTL_SVM_ATTR_PREFERRED_LOC
4000 	 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC
4001 	 * KFD_IOCTL_SVM_ATTR_SET_FLAGS
4002 	 * KFD_IOCTL_SVM_ATTR_GRANULARITY
4003 	 *
4004 	 * ** ACCESSBILITY ATTRIBUTES **
4005 	 * (Considered as one, type is altered during query, value is gpuid)
4006 	 * KFD_IOCTL_SVM_ATTR_ACCESS
4007 	 * KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE
4008 	 * KFD_IOCTL_SVM_ATTR_NO_ACCESS
4009 	 */
4010 	if (*num_svm_ranges > 0) {
4011 		common_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4012 			nattr_common;
4013 		accessibility_size = sizeof(struct kfd_ioctl_svm_attribute) *
4014 			nattr_accessibility * num_devices;
4015 
4016 		total_size = sizeof(struct kfd_criu_svm_range_priv_data) +
4017 			common_attr_size + accessibility_size;
4018 
4019 		*svm_priv_data_size = *num_svm_ranges * total_size;
4020 	}
4021 
4022 	pr_debug("num_svm_ranges %u total_priv_size %llu\n", *num_svm_ranges,
4023 		 *svm_priv_data_size);
4024 	return 0;
4025 }
4026 
4027 int kfd_criu_checkpoint_svm(struct kfd_process *p,
4028 			    uint8_t __user *user_priv_data,
4029 			    uint64_t *priv_data_offset)
4030 {
4031 	struct kfd_criu_svm_range_priv_data *svm_priv = NULL;
4032 	struct kfd_ioctl_svm_attribute *query_attr = NULL;
4033 	uint64_t svm_priv_data_size, query_attr_size = 0;
4034 	int index, nattr_common = 4, ret = 0;
4035 	struct svm_range_list *svms;
4036 	int num_devices = p->n_pdds;
4037 	struct svm_range *prange;
4038 	struct mm_struct *mm;
4039 
4040 	svms = &p->svms;
4041 	if (!svms)
4042 		return -EINVAL;
4043 
4044 	mm = get_task_mm(p->lead_thread);
4045 	if (!mm) {
4046 		pr_err("failed to get mm for the target process\n");
4047 		return -ESRCH;
4048 	}
4049 
4050 	query_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4051 				(nattr_common + num_devices);
4052 
4053 	query_attr = kzalloc(query_attr_size, GFP_KERNEL);
4054 	if (!query_attr) {
4055 		ret = -ENOMEM;
4056 		goto exit;
4057 	}
4058 
4059 	query_attr[0].type = KFD_IOCTL_SVM_ATTR_PREFERRED_LOC;
4060 	query_attr[1].type = KFD_IOCTL_SVM_ATTR_PREFETCH_LOC;
4061 	query_attr[2].type = KFD_IOCTL_SVM_ATTR_SET_FLAGS;
4062 	query_attr[3].type = KFD_IOCTL_SVM_ATTR_GRANULARITY;
4063 
4064 	for (index = 0; index < num_devices; index++) {
4065 		struct kfd_process_device *pdd = p->pdds[index];
4066 
4067 		query_attr[index + nattr_common].type =
4068 			KFD_IOCTL_SVM_ATTR_ACCESS;
4069 		query_attr[index + nattr_common].value = pdd->user_gpu_id;
4070 	}
4071 
4072 	svm_priv_data_size = sizeof(*svm_priv) + query_attr_size;
4073 
4074 	svm_priv = kzalloc(svm_priv_data_size, GFP_KERNEL);
4075 	if (!svm_priv) {
4076 		ret = -ENOMEM;
4077 		goto exit_query;
4078 	}
4079 
4080 	index = 0;
4081 	list_for_each_entry(prange, &svms->list, list) {
4082 
4083 		svm_priv->object_type = KFD_CRIU_OBJECT_TYPE_SVM_RANGE;
4084 		svm_priv->start_addr = prange->start;
4085 		svm_priv->size = prange->npages;
4086 		memcpy(&svm_priv->attrs, query_attr, query_attr_size);
4087 		pr_debug("CRIU: prange: 0x%p start: 0x%lx\t npages: 0x%llx end: 0x%llx\t size: 0x%llx\n",
4088 			 prange, prange->start, prange->npages,
4089 			 prange->start + prange->npages - 1,
4090 			 prange->npages * PAGE_SIZE);
4091 
4092 		ret = svm_range_get_attr(p, mm, svm_priv->start_addr,
4093 					 svm_priv->size,
4094 					 (nattr_common + num_devices),
4095 					 svm_priv->attrs);
4096 		if (ret) {
4097 			pr_err("CRIU: failed to obtain range attributes\n");
4098 			goto exit_priv;
4099 		}
4100 
4101 		if (copy_to_user(user_priv_data + *priv_data_offset, svm_priv,
4102 				 svm_priv_data_size)) {
4103 			pr_err("Failed to copy svm priv to user\n");
4104 			ret = -EFAULT;
4105 			goto exit_priv;
4106 		}
4107 
4108 		*priv_data_offset += svm_priv_data_size;
4109 
4110 	}
4111 
4112 
4113 exit_priv:
4114 	kfree(svm_priv);
4115 exit_query:
4116 	kfree(query_attr);
4117 exit:
4118 	mmput(mm);
4119 	return ret;
4120 }
4121 
4122 int
4123 svm_ioctl(struct kfd_process *p, enum kfd_ioctl_svm_op op, uint64_t start,
4124 	  uint64_t size, uint32_t nattrs, struct kfd_ioctl_svm_attribute *attrs)
4125 {
4126 	struct mm_struct *mm = current->mm;
4127 	int r;
4128 
4129 	start >>= PAGE_SHIFT;
4130 	size >>= PAGE_SHIFT;
4131 
4132 	switch (op) {
4133 	case KFD_IOCTL_SVM_OP_SET_ATTR:
4134 		r = svm_range_set_attr(p, mm, start, size, nattrs, attrs);
4135 		break;
4136 	case KFD_IOCTL_SVM_OP_GET_ATTR:
4137 		r = svm_range_get_attr(p, mm, start, size, nattrs, attrs);
4138 		break;
4139 	default:
4140 		r = EINVAL;
4141 		break;
4142 	}
4143 
4144 	return r;
4145 }
4146