xref: /openbmc/linux/drivers/gpu/drm/amd/amdkfd/kfd_svm.c (revision 1d8355ad922423c9f765a644ed04526a6273d9ee)
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 <drm/ttm/ttm_tt.h>
27 #include "amdgpu_sync.h"
28 #include "amdgpu_object.h"
29 #include "amdgpu_vm.h"
30 #include "amdgpu_hmm.h"
31 #include "amdgpu.h"
32 #include "amdgpu_xgmi.h"
33 #include "kfd_priv.h"
34 #include "kfd_svm.h"
35 #include "kfd_migrate.h"
36 #include "kfd_smi_events.h"
37 
38 #ifdef dev_fmt
39 #undef dev_fmt
40 #endif
41 #define dev_fmt(fmt) "kfd_svm: %s: " fmt, __func__
42 
43 #define AMDGPU_SVM_RANGE_RESTORE_DELAY_MS 1
44 
45 /* Long enough to ensure no retry fault comes after svm range is restored and
46  * page table is updated.
47  */
48 #define AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING	(2UL * NSEC_PER_MSEC)
49 
50 /* Giant svm range split into smaller ranges based on this, it is decided using
51  * minimum of all dGPU/APU 1/32 VRAM size, between 2MB to 1GB and alignment to
52  * power of 2MB.
53  */
54 static uint64_t max_svm_range_pages;
55 
56 struct criu_svm_metadata {
57 	struct list_head list;
58 	struct kfd_criu_svm_range_priv_data data;
59 };
60 
61 static void svm_range_evict_svm_bo_worker(struct work_struct *work);
62 static bool
63 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
64 				    const struct mmu_notifier_range *range,
65 				    unsigned long cur_seq);
66 static int
67 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
68 		   uint64_t *bo_s, uint64_t *bo_l);
69 static const struct mmu_interval_notifier_ops svm_range_mn_ops = {
70 	.invalidate = svm_range_cpu_invalidate_pagetables,
71 };
72 
73 /**
74  * svm_range_unlink - unlink svm_range from lists and interval tree
75  * @prange: svm range structure to be removed
76  *
77  * Remove the svm_range from the svms and svm_bo lists and the svms
78  * interval tree.
79  *
80  * Context: The caller must hold svms->lock
81  */
82 static void svm_range_unlink(struct svm_range *prange)
83 {
84 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
85 		 prange, prange->start, prange->last);
86 
87 	if (prange->svm_bo) {
88 		spin_lock(&prange->svm_bo->list_lock);
89 		list_del(&prange->svm_bo_list);
90 		spin_unlock(&prange->svm_bo->list_lock);
91 	}
92 
93 	list_del(&prange->list);
94 	if (prange->it_node.start != 0 && prange->it_node.last != 0)
95 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
96 }
97 
98 static void
99 svm_range_add_notifier_locked(struct mm_struct *mm, struct svm_range *prange)
100 {
101 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
102 		 prange, prange->start, prange->last);
103 
104 	mmu_interval_notifier_insert_locked(&prange->notifier, mm,
105 				     prange->start << PAGE_SHIFT,
106 				     prange->npages << PAGE_SHIFT,
107 				     &svm_range_mn_ops);
108 }
109 
110 /**
111  * svm_range_add_to_svms - add svm range to svms
112  * @prange: svm range structure to be added
113  *
114  * Add the svm range to svms interval tree and link list
115  *
116  * Context: The caller must hold svms->lock
117  */
118 static void svm_range_add_to_svms(struct svm_range *prange)
119 {
120 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
121 		 prange, prange->start, prange->last);
122 
123 	list_move_tail(&prange->list, &prange->svms->list);
124 	prange->it_node.start = prange->start;
125 	prange->it_node.last = prange->last;
126 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
127 }
128 
129 static void svm_range_remove_notifier(struct svm_range *prange)
130 {
131 	pr_debug("remove notifier svms 0x%p prange 0x%p [0x%lx 0x%lx]\n",
132 		 prange->svms, prange,
133 		 prange->notifier.interval_tree.start >> PAGE_SHIFT,
134 		 prange->notifier.interval_tree.last >> PAGE_SHIFT);
135 
136 	if (prange->notifier.interval_tree.start != 0 &&
137 	    prange->notifier.interval_tree.last != 0)
138 		mmu_interval_notifier_remove(&prange->notifier);
139 }
140 
141 static bool
142 svm_is_valid_dma_mapping_addr(struct device *dev, dma_addr_t dma_addr)
143 {
144 	return dma_addr && !dma_mapping_error(dev, dma_addr) &&
145 	       !(dma_addr & SVM_RANGE_VRAM_DOMAIN);
146 }
147 
148 static int
149 svm_range_dma_map_dev(struct amdgpu_device *adev, struct svm_range *prange,
150 		      unsigned long offset, unsigned long npages,
151 		      unsigned long *hmm_pfns, uint32_t gpuidx)
152 {
153 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
154 	dma_addr_t *addr = prange->dma_addr[gpuidx];
155 	struct device *dev = adev->dev;
156 	struct page *page;
157 	int i, r;
158 
159 	if (!addr) {
160 		addr = kvcalloc(prange->npages, sizeof(*addr), GFP_KERNEL);
161 		if (!addr)
162 			return -ENOMEM;
163 		prange->dma_addr[gpuidx] = addr;
164 	}
165 
166 	addr += offset;
167 	for (i = 0; i < npages; i++) {
168 		if (svm_is_valid_dma_mapping_addr(dev, addr[i]))
169 			dma_unmap_page(dev, addr[i], PAGE_SIZE, dir);
170 
171 		page = hmm_pfn_to_page(hmm_pfns[i]);
172 		if (is_zone_device_page(page)) {
173 			struct amdgpu_device *bo_adev =
174 					amdgpu_ttm_adev(prange->svm_bo->bo->tbo.bdev);
175 
176 			addr[i] = (hmm_pfns[i] << PAGE_SHIFT) +
177 				   bo_adev->vm_manager.vram_base_offset -
178 				   bo_adev->kfd.dev->pgmap.range.start;
179 			addr[i] |= SVM_RANGE_VRAM_DOMAIN;
180 			pr_debug_ratelimited("vram address: 0x%llx\n", addr[i]);
181 			continue;
182 		}
183 		addr[i] = dma_map_page(dev, page, 0, PAGE_SIZE, dir);
184 		r = dma_mapping_error(dev, addr[i]);
185 		if (r) {
186 			dev_err(dev, "failed %d dma_map_page\n", r);
187 			return r;
188 		}
189 		pr_debug_ratelimited("dma mapping 0x%llx for page addr 0x%lx\n",
190 				     addr[i] >> PAGE_SHIFT, page_to_pfn(page));
191 	}
192 	return 0;
193 }
194 
195 static int
196 svm_range_dma_map(struct svm_range *prange, unsigned long *bitmap,
197 		  unsigned long offset, unsigned long npages,
198 		  unsigned long *hmm_pfns)
199 {
200 	struct kfd_process *p;
201 	uint32_t gpuidx;
202 	int r;
203 
204 	p = container_of(prange->svms, struct kfd_process, svms);
205 
206 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
207 		struct kfd_process_device *pdd;
208 
209 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
210 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
211 		if (!pdd) {
212 			pr_debug("failed to find device idx %d\n", gpuidx);
213 			return -EINVAL;
214 		}
215 
216 		r = svm_range_dma_map_dev(pdd->dev->adev, prange, offset, npages,
217 					  hmm_pfns, gpuidx);
218 		if (r)
219 			break;
220 	}
221 
222 	return r;
223 }
224 
225 void svm_range_dma_unmap(struct device *dev, dma_addr_t *dma_addr,
226 			 unsigned long offset, unsigned long npages)
227 {
228 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
229 	int i;
230 
231 	if (!dma_addr)
232 		return;
233 
234 	for (i = offset; i < offset + npages; i++) {
235 		if (!svm_is_valid_dma_mapping_addr(dev, dma_addr[i]))
236 			continue;
237 		pr_debug_ratelimited("unmap 0x%llx\n", dma_addr[i] >> PAGE_SHIFT);
238 		dma_unmap_page(dev, dma_addr[i], PAGE_SIZE, dir);
239 		dma_addr[i] = 0;
240 	}
241 }
242 
243 void svm_range_free_dma_mappings(struct svm_range *prange)
244 {
245 	struct kfd_process_device *pdd;
246 	dma_addr_t *dma_addr;
247 	struct device *dev;
248 	struct kfd_process *p;
249 	uint32_t gpuidx;
250 
251 	p = container_of(prange->svms, struct kfd_process, svms);
252 
253 	for (gpuidx = 0; gpuidx < MAX_GPU_INSTANCE; gpuidx++) {
254 		dma_addr = prange->dma_addr[gpuidx];
255 		if (!dma_addr)
256 			continue;
257 
258 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
259 		if (!pdd) {
260 			pr_debug("failed to find device idx %d\n", gpuidx);
261 			continue;
262 		}
263 		dev = &pdd->dev->adev->pdev->dev;
264 		svm_range_dma_unmap(dev, dma_addr, 0, prange->npages);
265 		kvfree(dma_addr);
266 		prange->dma_addr[gpuidx] = NULL;
267 	}
268 }
269 
270 static void svm_range_free(struct svm_range *prange, bool update_mem_usage)
271 {
272 	uint64_t size = (prange->last - prange->start + 1) << PAGE_SHIFT;
273 	struct kfd_process *p = container_of(prange->svms, struct kfd_process, svms);
274 
275 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms, prange,
276 		 prange->start, prange->last);
277 
278 	svm_range_vram_node_free(prange);
279 	svm_range_free_dma_mappings(prange);
280 
281 	if (update_mem_usage && !p->xnack_enabled) {
282 		pr_debug("unreserve prange 0x%p size: 0x%llx\n", prange, size);
283 		amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
284 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR);
285 	}
286 	mutex_destroy(&prange->lock);
287 	mutex_destroy(&prange->migrate_mutex);
288 	kfree(prange);
289 }
290 
291 static void
292 svm_range_set_default_attributes(int32_t *location, int32_t *prefetch_loc,
293 				 uint8_t *granularity, uint32_t *flags)
294 {
295 	*location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
296 	*prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
297 	*granularity = 9;
298 	*flags =
299 		KFD_IOCTL_SVM_FLAG_HOST_ACCESS | KFD_IOCTL_SVM_FLAG_COHERENT;
300 }
301 
302 static struct
303 svm_range *svm_range_new(struct svm_range_list *svms, uint64_t start,
304 			 uint64_t last, bool update_mem_usage)
305 {
306 	uint64_t size = last - start + 1;
307 	struct svm_range *prange;
308 	struct kfd_process *p;
309 
310 	prange = kzalloc(sizeof(*prange), GFP_KERNEL);
311 	if (!prange)
312 		return NULL;
313 
314 	p = container_of(svms, struct kfd_process, svms);
315 	if (!p->xnack_enabled && update_mem_usage &&
316 	    amdgpu_amdkfd_reserve_mem_limit(NULL, size << PAGE_SHIFT,
317 					    KFD_IOC_ALLOC_MEM_FLAGS_USERPTR)) {
318 		pr_info("SVM mapping failed, exceeds resident system memory limit\n");
319 		kfree(prange);
320 		return NULL;
321 	}
322 	prange->npages = size;
323 	prange->svms = svms;
324 	prange->start = start;
325 	prange->last = last;
326 	INIT_LIST_HEAD(&prange->list);
327 	INIT_LIST_HEAD(&prange->update_list);
328 	INIT_LIST_HEAD(&prange->svm_bo_list);
329 	INIT_LIST_HEAD(&prange->deferred_list);
330 	INIT_LIST_HEAD(&prange->child_list);
331 	atomic_set(&prange->invalid, 0);
332 	prange->validate_timestamp = 0;
333 	mutex_init(&prange->migrate_mutex);
334 	mutex_init(&prange->lock);
335 
336 	if (p->xnack_enabled)
337 		bitmap_copy(prange->bitmap_access, svms->bitmap_supported,
338 			    MAX_GPU_INSTANCE);
339 
340 	svm_range_set_default_attributes(&prange->preferred_loc,
341 					 &prange->prefetch_loc,
342 					 &prange->granularity, &prange->flags);
343 
344 	pr_debug("svms 0x%p [0x%llx 0x%llx]\n", svms, start, last);
345 
346 	return prange;
347 }
348 
349 static bool svm_bo_ref_unless_zero(struct svm_range_bo *svm_bo)
350 {
351 	if (!svm_bo || !kref_get_unless_zero(&svm_bo->kref))
352 		return false;
353 
354 	return true;
355 }
356 
357 static void svm_range_bo_release(struct kref *kref)
358 {
359 	struct svm_range_bo *svm_bo;
360 
361 	svm_bo = container_of(kref, struct svm_range_bo, kref);
362 	pr_debug("svm_bo 0x%p\n", svm_bo);
363 
364 	spin_lock(&svm_bo->list_lock);
365 	while (!list_empty(&svm_bo->range_list)) {
366 		struct svm_range *prange =
367 				list_first_entry(&svm_bo->range_list,
368 						struct svm_range, svm_bo_list);
369 		/* list_del_init tells a concurrent svm_range_vram_node_new when
370 		 * it's safe to reuse the svm_bo pointer and svm_bo_list head.
371 		 */
372 		list_del_init(&prange->svm_bo_list);
373 		spin_unlock(&svm_bo->list_lock);
374 
375 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
376 			 prange->start, prange->last);
377 		mutex_lock(&prange->lock);
378 		prange->svm_bo = NULL;
379 		mutex_unlock(&prange->lock);
380 
381 		spin_lock(&svm_bo->list_lock);
382 	}
383 	spin_unlock(&svm_bo->list_lock);
384 	if (!dma_fence_is_signaled(&svm_bo->eviction_fence->base)) {
385 		/* We're not in the eviction worker.
386 		 * Signal the fence and synchronize with any
387 		 * pending eviction work.
388 		 */
389 		dma_fence_signal(&svm_bo->eviction_fence->base);
390 		cancel_work_sync(&svm_bo->eviction_work);
391 	}
392 	dma_fence_put(&svm_bo->eviction_fence->base);
393 	amdgpu_bo_unref(&svm_bo->bo);
394 	kfree(svm_bo);
395 }
396 
397 static void svm_range_bo_wq_release(struct work_struct *work)
398 {
399 	struct svm_range_bo *svm_bo;
400 
401 	svm_bo = container_of(work, struct svm_range_bo, release_work);
402 	svm_range_bo_release(&svm_bo->kref);
403 }
404 
405 static void svm_range_bo_release_async(struct kref *kref)
406 {
407 	struct svm_range_bo *svm_bo;
408 
409 	svm_bo = container_of(kref, struct svm_range_bo, kref);
410 	pr_debug("svm_bo 0x%p\n", svm_bo);
411 	INIT_WORK(&svm_bo->release_work, svm_range_bo_wq_release);
412 	schedule_work(&svm_bo->release_work);
413 }
414 
415 void svm_range_bo_unref_async(struct svm_range_bo *svm_bo)
416 {
417 	kref_put(&svm_bo->kref, svm_range_bo_release_async);
418 }
419 
420 static void svm_range_bo_unref(struct svm_range_bo *svm_bo)
421 {
422 	if (svm_bo)
423 		kref_put(&svm_bo->kref, svm_range_bo_release);
424 }
425 
426 static bool
427 svm_range_validate_svm_bo(struct amdgpu_device *adev, struct svm_range *prange)
428 {
429 	struct amdgpu_device *bo_adev;
430 
431 	mutex_lock(&prange->lock);
432 	if (!prange->svm_bo) {
433 		mutex_unlock(&prange->lock);
434 		return false;
435 	}
436 	if (prange->ttm_res) {
437 		/* We still have a reference, all is well */
438 		mutex_unlock(&prange->lock);
439 		return true;
440 	}
441 	if (svm_bo_ref_unless_zero(prange->svm_bo)) {
442 		/*
443 		 * Migrate from GPU to GPU, remove range from source bo_adev
444 		 * svm_bo range list, and return false to allocate svm_bo from
445 		 * destination adev.
446 		 */
447 		bo_adev = amdgpu_ttm_adev(prange->svm_bo->bo->tbo.bdev);
448 		if (bo_adev != adev) {
449 			mutex_unlock(&prange->lock);
450 
451 			spin_lock(&prange->svm_bo->list_lock);
452 			list_del_init(&prange->svm_bo_list);
453 			spin_unlock(&prange->svm_bo->list_lock);
454 
455 			svm_range_bo_unref(prange->svm_bo);
456 			return false;
457 		}
458 		if (READ_ONCE(prange->svm_bo->evicting)) {
459 			struct dma_fence *f;
460 			struct svm_range_bo *svm_bo;
461 			/* The BO is getting evicted,
462 			 * we need to get a new one
463 			 */
464 			mutex_unlock(&prange->lock);
465 			svm_bo = prange->svm_bo;
466 			f = dma_fence_get(&svm_bo->eviction_fence->base);
467 			svm_range_bo_unref(prange->svm_bo);
468 			/* wait for the fence to avoid long spin-loop
469 			 * at list_empty_careful
470 			 */
471 			dma_fence_wait(f, false);
472 			dma_fence_put(f);
473 		} else {
474 			/* The BO was still around and we got
475 			 * a new reference to it
476 			 */
477 			mutex_unlock(&prange->lock);
478 			pr_debug("reuse old bo svms 0x%p [0x%lx 0x%lx]\n",
479 				 prange->svms, prange->start, prange->last);
480 
481 			prange->ttm_res = prange->svm_bo->bo->tbo.resource;
482 			return true;
483 		}
484 
485 	} else {
486 		mutex_unlock(&prange->lock);
487 	}
488 
489 	/* We need a new svm_bo. Spin-loop to wait for concurrent
490 	 * svm_range_bo_release to finish removing this range from
491 	 * its range list. After this, it is safe to reuse the
492 	 * svm_bo pointer and svm_bo_list head.
493 	 */
494 	while (!list_empty_careful(&prange->svm_bo_list))
495 		;
496 
497 	return false;
498 }
499 
500 static struct svm_range_bo *svm_range_bo_new(void)
501 {
502 	struct svm_range_bo *svm_bo;
503 
504 	svm_bo = kzalloc(sizeof(*svm_bo), GFP_KERNEL);
505 	if (!svm_bo)
506 		return NULL;
507 
508 	kref_init(&svm_bo->kref);
509 	INIT_LIST_HEAD(&svm_bo->range_list);
510 	spin_lock_init(&svm_bo->list_lock);
511 
512 	return svm_bo;
513 }
514 
515 int
516 svm_range_vram_node_new(struct amdgpu_device *adev, struct svm_range *prange,
517 			bool clear)
518 {
519 	struct amdgpu_bo_param bp;
520 	struct svm_range_bo *svm_bo;
521 	struct amdgpu_bo_user *ubo;
522 	struct amdgpu_bo *bo;
523 	struct kfd_process *p;
524 	struct mm_struct *mm;
525 	int r;
526 
527 	p = container_of(prange->svms, struct kfd_process, svms);
528 	pr_debug("pasid: %x svms 0x%p [0x%lx 0x%lx]\n", p->pasid, prange->svms,
529 		 prange->start, prange->last);
530 
531 	if (svm_range_validate_svm_bo(adev, prange))
532 		return 0;
533 
534 	svm_bo = svm_range_bo_new();
535 	if (!svm_bo) {
536 		pr_debug("failed to alloc svm bo\n");
537 		return -ENOMEM;
538 	}
539 	mm = get_task_mm(p->lead_thread);
540 	if (!mm) {
541 		pr_debug("failed to get mm\n");
542 		kfree(svm_bo);
543 		return -ESRCH;
544 	}
545 	svm_bo->eviction_fence =
546 		amdgpu_amdkfd_fence_create(dma_fence_context_alloc(1),
547 					   mm,
548 					   svm_bo);
549 	mmput(mm);
550 	INIT_WORK(&svm_bo->eviction_work, svm_range_evict_svm_bo_worker);
551 	svm_bo->evicting = 0;
552 	memset(&bp, 0, sizeof(bp));
553 	bp.size = prange->npages * PAGE_SIZE;
554 	bp.byte_align = PAGE_SIZE;
555 	bp.domain = AMDGPU_GEM_DOMAIN_VRAM;
556 	bp.flags = AMDGPU_GEM_CREATE_NO_CPU_ACCESS;
557 	bp.flags |= clear ? AMDGPU_GEM_CREATE_VRAM_CLEARED : 0;
558 	bp.flags |= AMDGPU_GEM_CREATE_DISCARDABLE;
559 	bp.type = ttm_bo_type_device;
560 	bp.resv = NULL;
561 
562 	r = amdgpu_bo_create_user(adev, &bp, &ubo);
563 	if (r) {
564 		pr_debug("failed %d to create bo\n", r);
565 		goto create_bo_failed;
566 	}
567 	bo = &ubo->bo;
568 	r = amdgpu_bo_reserve(bo, true);
569 	if (r) {
570 		pr_debug("failed %d to reserve bo\n", r);
571 		goto reserve_bo_failed;
572 	}
573 
574 	if (clear) {
575 		r = amdgpu_bo_sync_wait(bo, AMDGPU_FENCE_OWNER_KFD, false);
576 		if (r) {
577 			pr_debug("failed %d to sync bo\n", r);
578 			amdgpu_bo_unreserve(bo);
579 			goto reserve_bo_failed;
580 		}
581 	}
582 
583 	r = dma_resv_reserve_fences(bo->tbo.base.resv, 1);
584 	if (r) {
585 		pr_debug("failed %d to reserve bo\n", r);
586 		amdgpu_bo_unreserve(bo);
587 		goto reserve_bo_failed;
588 	}
589 	amdgpu_bo_fence(bo, &svm_bo->eviction_fence->base, true);
590 
591 	amdgpu_bo_unreserve(bo);
592 
593 	svm_bo->bo = bo;
594 	prange->svm_bo = svm_bo;
595 	prange->ttm_res = bo->tbo.resource;
596 	prange->offset = 0;
597 
598 	spin_lock(&svm_bo->list_lock);
599 	list_add(&prange->svm_bo_list, &svm_bo->range_list);
600 	spin_unlock(&svm_bo->list_lock);
601 
602 	return 0;
603 
604 reserve_bo_failed:
605 	amdgpu_bo_unref(&bo);
606 create_bo_failed:
607 	dma_fence_put(&svm_bo->eviction_fence->base);
608 	kfree(svm_bo);
609 	prange->ttm_res = NULL;
610 
611 	return r;
612 }
613 
614 void svm_range_vram_node_free(struct svm_range *prange)
615 {
616 	svm_range_bo_unref(prange->svm_bo);
617 	prange->ttm_res = NULL;
618 }
619 
620 struct amdgpu_device *
621 svm_range_get_adev_by_id(struct svm_range *prange, uint32_t gpu_id)
622 {
623 	struct kfd_process_device *pdd;
624 	struct kfd_process *p;
625 	int32_t gpu_idx;
626 
627 	p = container_of(prange->svms, struct kfd_process, svms);
628 
629 	gpu_idx = kfd_process_gpuidx_from_gpuid(p, gpu_id);
630 	if (gpu_idx < 0) {
631 		pr_debug("failed to get device by id 0x%x\n", gpu_id);
632 		return NULL;
633 	}
634 	pdd = kfd_process_device_from_gpuidx(p, gpu_idx);
635 	if (!pdd) {
636 		pr_debug("failed to get device by idx 0x%x\n", gpu_idx);
637 		return NULL;
638 	}
639 
640 	return pdd->dev->adev;
641 }
642 
643 struct kfd_process_device *
644 svm_range_get_pdd_by_adev(struct svm_range *prange, struct amdgpu_device *adev)
645 {
646 	struct kfd_process *p;
647 	int32_t gpu_idx, gpuid;
648 	int r;
649 
650 	p = container_of(prange->svms, struct kfd_process, svms);
651 
652 	r = kfd_process_gpuid_from_adev(p, adev, &gpuid, &gpu_idx);
653 	if (r) {
654 		pr_debug("failed to get device id by adev %p\n", adev);
655 		return NULL;
656 	}
657 
658 	return kfd_process_device_from_gpuidx(p, gpu_idx);
659 }
660 
661 static int svm_range_bo_validate(void *param, struct amdgpu_bo *bo)
662 {
663 	struct ttm_operation_ctx ctx = { false, false };
664 
665 	amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_VRAM);
666 
667 	return ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
668 }
669 
670 static int
671 svm_range_check_attr(struct kfd_process *p,
672 		     uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
673 {
674 	uint32_t i;
675 
676 	for (i = 0; i < nattr; i++) {
677 		uint32_t val = attrs[i].value;
678 		int gpuidx = MAX_GPU_INSTANCE;
679 
680 		switch (attrs[i].type) {
681 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
682 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM &&
683 			    val != KFD_IOCTL_SVM_LOCATION_UNDEFINED)
684 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
685 			break;
686 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
687 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM)
688 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
689 			break;
690 		case KFD_IOCTL_SVM_ATTR_ACCESS:
691 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
692 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
693 			gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
694 			break;
695 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
696 			break;
697 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
698 			break;
699 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
700 			break;
701 		default:
702 			pr_debug("unknown attr type 0x%x\n", attrs[i].type);
703 			return -EINVAL;
704 		}
705 
706 		if (gpuidx < 0) {
707 			pr_debug("no GPU 0x%x found\n", val);
708 			return -EINVAL;
709 		} else if (gpuidx < MAX_GPU_INSTANCE &&
710 			   !test_bit(gpuidx, p->svms.bitmap_supported)) {
711 			pr_debug("GPU 0x%x not supported\n", val);
712 			return -EINVAL;
713 		}
714 	}
715 
716 	return 0;
717 }
718 
719 static void
720 svm_range_apply_attrs(struct kfd_process *p, struct svm_range *prange,
721 		      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
722 		      bool *update_mapping)
723 {
724 	uint32_t i;
725 	int gpuidx;
726 
727 	for (i = 0; i < nattr; i++) {
728 		switch (attrs[i].type) {
729 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
730 			prange->preferred_loc = attrs[i].value;
731 			break;
732 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
733 			prange->prefetch_loc = attrs[i].value;
734 			break;
735 		case KFD_IOCTL_SVM_ATTR_ACCESS:
736 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
737 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
738 			if (!p->xnack_enabled)
739 				*update_mapping = true;
740 
741 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
742 							       attrs[i].value);
743 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
744 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
745 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
746 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
747 				bitmap_set(prange->bitmap_access, gpuidx, 1);
748 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
749 			} else {
750 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
751 				bitmap_set(prange->bitmap_aip, gpuidx, 1);
752 			}
753 			break;
754 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
755 			*update_mapping = true;
756 			prange->flags |= attrs[i].value;
757 			break;
758 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
759 			*update_mapping = true;
760 			prange->flags &= ~attrs[i].value;
761 			break;
762 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
763 			prange->granularity = attrs[i].value;
764 			break;
765 		default:
766 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
767 		}
768 	}
769 }
770 
771 static bool
772 svm_range_is_same_attrs(struct kfd_process *p, struct svm_range *prange,
773 			uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
774 {
775 	uint32_t i;
776 	int gpuidx;
777 
778 	for (i = 0; i < nattr; i++) {
779 		switch (attrs[i].type) {
780 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
781 			if (prange->preferred_loc != attrs[i].value)
782 				return false;
783 			break;
784 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
785 			/* Prefetch should always trigger a migration even
786 			 * if the value of the attribute didn't change.
787 			 */
788 			return false;
789 		case KFD_IOCTL_SVM_ATTR_ACCESS:
790 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
791 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
792 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
793 							       attrs[i].value);
794 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
795 				if (test_bit(gpuidx, prange->bitmap_access) ||
796 				    test_bit(gpuidx, prange->bitmap_aip))
797 					return false;
798 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
799 				if (!test_bit(gpuidx, prange->bitmap_access))
800 					return false;
801 			} else {
802 				if (!test_bit(gpuidx, prange->bitmap_aip))
803 					return false;
804 			}
805 			break;
806 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
807 			if ((prange->flags & attrs[i].value) != attrs[i].value)
808 				return false;
809 			break;
810 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
811 			if ((prange->flags & attrs[i].value) != 0)
812 				return false;
813 			break;
814 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
815 			if (prange->granularity != attrs[i].value)
816 				return false;
817 			break;
818 		default:
819 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
820 		}
821 	}
822 
823 	return true;
824 }
825 
826 /**
827  * svm_range_debug_dump - print all range information from svms
828  * @svms: svm range list header
829  *
830  * debug output svm range start, end, prefetch location from svms
831  * interval tree and link list
832  *
833  * Context: The caller must hold svms->lock
834  */
835 static void svm_range_debug_dump(struct svm_range_list *svms)
836 {
837 	struct interval_tree_node *node;
838 	struct svm_range *prange;
839 
840 	pr_debug("dump svms 0x%p list\n", svms);
841 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
842 
843 	list_for_each_entry(prange, &svms->list, list) {
844 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
845 			 prange, prange->start, prange->npages,
846 			 prange->start + prange->npages - 1,
847 			 prange->actual_loc);
848 	}
849 
850 	pr_debug("dump svms 0x%p interval tree\n", svms);
851 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
852 	node = interval_tree_iter_first(&svms->objects, 0, ~0ULL);
853 	while (node) {
854 		prange = container_of(node, struct svm_range, it_node);
855 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
856 			 prange, prange->start, prange->npages,
857 			 prange->start + prange->npages - 1,
858 			 prange->actual_loc);
859 		node = interval_tree_iter_next(node, 0, ~0ULL);
860 	}
861 }
862 
863 static int
864 svm_range_split_array(void *ppnew, void *ppold, size_t size,
865 		      uint64_t old_start, uint64_t old_n,
866 		      uint64_t new_start, uint64_t new_n)
867 {
868 	unsigned char *new, *old, *pold;
869 	uint64_t d;
870 
871 	if (!ppold)
872 		return 0;
873 	pold = *(unsigned char **)ppold;
874 	if (!pold)
875 		return 0;
876 
877 	new = kvmalloc_array(new_n, size, GFP_KERNEL);
878 	if (!new)
879 		return -ENOMEM;
880 
881 	d = (new_start - old_start) * size;
882 	memcpy(new, pold + d, new_n * size);
883 
884 	old = kvmalloc_array(old_n, size, GFP_KERNEL);
885 	if (!old) {
886 		kvfree(new);
887 		return -ENOMEM;
888 	}
889 
890 	d = (new_start == old_start) ? new_n * size : 0;
891 	memcpy(old, pold + d, old_n * size);
892 
893 	kvfree(pold);
894 	*(void **)ppold = old;
895 	*(void **)ppnew = new;
896 
897 	return 0;
898 }
899 
900 static int
901 svm_range_split_pages(struct svm_range *new, struct svm_range *old,
902 		      uint64_t start, uint64_t last)
903 {
904 	uint64_t npages = last - start + 1;
905 	int i, r;
906 
907 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
908 		r = svm_range_split_array(&new->dma_addr[i], &old->dma_addr[i],
909 					  sizeof(*old->dma_addr[i]), old->start,
910 					  npages, new->start, new->npages);
911 		if (r)
912 			return r;
913 	}
914 
915 	return 0;
916 }
917 
918 static int
919 svm_range_split_nodes(struct svm_range *new, struct svm_range *old,
920 		      uint64_t start, uint64_t last)
921 {
922 	uint64_t npages = last - start + 1;
923 
924 	pr_debug("svms 0x%p new prange 0x%p start 0x%lx [0x%llx 0x%llx]\n",
925 		 new->svms, new, new->start, start, last);
926 
927 	if (new->start == old->start) {
928 		new->offset = old->offset;
929 		old->offset += new->npages;
930 	} else {
931 		new->offset = old->offset + npages;
932 	}
933 
934 	new->svm_bo = svm_range_bo_ref(old->svm_bo);
935 	new->ttm_res = old->ttm_res;
936 
937 	spin_lock(&new->svm_bo->list_lock);
938 	list_add(&new->svm_bo_list, &new->svm_bo->range_list);
939 	spin_unlock(&new->svm_bo->list_lock);
940 
941 	return 0;
942 }
943 
944 /**
945  * svm_range_split_adjust - split range and adjust
946  *
947  * @new: new range
948  * @old: the old range
949  * @start: the old range adjust to start address in pages
950  * @last: the old range adjust to last address in pages
951  *
952  * Copy system memory dma_addr or vram ttm_res in old range to new
953  * range from new_start up to size new->npages, the remaining old range is from
954  * start to last
955  *
956  * Return:
957  * 0 - OK, -ENOMEM - out of memory
958  */
959 static int
960 svm_range_split_adjust(struct svm_range *new, struct svm_range *old,
961 		      uint64_t start, uint64_t last)
962 {
963 	int r;
964 
965 	pr_debug("svms 0x%p new 0x%lx old [0x%lx 0x%lx] => [0x%llx 0x%llx]\n",
966 		 new->svms, new->start, old->start, old->last, start, last);
967 
968 	if (new->start < old->start ||
969 	    new->last > old->last) {
970 		WARN_ONCE(1, "invalid new range start or last\n");
971 		return -EINVAL;
972 	}
973 
974 	r = svm_range_split_pages(new, old, start, last);
975 	if (r)
976 		return r;
977 
978 	if (old->actual_loc && old->ttm_res) {
979 		r = svm_range_split_nodes(new, old, start, last);
980 		if (r)
981 			return r;
982 	}
983 
984 	old->npages = last - start + 1;
985 	old->start = start;
986 	old->last = last;
987 	new->flags = old->flags;
988 	new->preferred_loc = old->preferred_loc;
989 	new->prefetch_loc = old->prefetch_loc;
990 	new->actual_loc = old->actual_loc;
991 	new->granularity = old->granularity;
992 	new->mapped_to_gpu = old->mapped_to_gpu;
993 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
994 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
995 
996 	return 0;
997 }
998 
999 /**
1000  * svm_range_split - split a range in 2 ranges
1001  *
1002  * @prange: the svm range to split
1003  * @start: the remaining range start address in pages
1004  * @last: the remaining range last address in pages
1005  * @new: the result new range generated
1006  *
1007  * Two cases only:
1008  * case 1: if start == prange->start
1009  *         prange ==> prange[start, last]
1010  *         new range [last + 1, prange->last]
1011  *
1012  * case 2: if last == prange->last
1013  *         prange ==> prange[start, last]
1014  *         new range [prange->start, start - 1]
1015  *
1016  * Return:
1017  * 0 - OK, -ENOMEM - out of memory, -EINVAL - invalid start, last
1018  */
1019 static int
1020 svm_range_split(struct svm_range *prange, uint64_t start, uint64_t last,
1021 		struct svm_range **new)
1022 {
1023 	uint64_t old_start = prange->start;
1024 	uint64_t old_last = prange->last;
1025 	struct svm_range_list *svms;
1026 	int r = 0;
1027 
1028 	pr_debug("svms 0x%p [0x%llx 0x%llx] to [0x%llx 0x%llx]\n", prange->svms,
1029 		 old_start, old_last, start, last);
1030 
1031 	if (old_start != start && old_last != last)
1032 		return -EINVAL;
1033 	if (start < old_start || last > old_last)
1034 		return -EINVAL;
1035 
1036 	svms = prange->svms;
1037 	if (old_start == start)
1038 		*new = svm_range_new(svms, last + 1, old_last, false);
1039 	else
1040 		*new = svm_range_new(svms, old_start, start - 1, false);
1041 	if (!*new)
1042 		return -ENOMEM;
1043 
1044 	r = svm_range_split_adjust(*new, prange, start, last);
1045 	if (r) {
1046 		pr_debug("failed %d split [0x%llx 0x%llx] to [0x%llx 0x%llx]\n",
1047 			 r, old_start, old_last, start, last);
1048 		svm_range_free(*new, false);
1049 		*new = NULL;
1050 	}
1051 
1052 	return r;
1053 }
1054 
1055 static int
1056 svm_range_split_tail(struct svm_range *prange,
1057 		     uint64_t new_last, struct list_head *insert_list)
1058 {
1059 	struct svm_range *tail;
1060 	int r = svm_range_split(prange, prange->start, new_last, &tail);
1061 
1062 	if (!r)
1063 		list_add(&tail->list, insert_list);
1064 	return r;
1065 }
1066 
1067 static int
1068 svm_range_split_head(struct svm_range *prange,
1069 		     uint64_t new_start, struct list_head *insert_list)
1070 {
1071 	struct svm_range *head;
1072 	int r = svm_range_split(prange, new_start, prange->last, &head);
1073 
1074 	if (!r)
1075 		list_add(&head->list, insert_list);
1076 	return r;
1077 }
1078 
1079 static void
1080 svm_range_add_child(struct svm_range *prange, struct mm_struct *mm,
1081 		    struct svm_range *pchild, enum svm_work_list_ops op)
1082 {
1083 	pr_debug("add child 0x%p [0x%lx 0x%lx] to prange 0x%p child list %d\n",
1084 		 pchild, pchild->start, pchild->last, prange, op);
1085 
1086 	pchild->work_item.mm = mm;
1087 	pchild->work_item.op = op;
1088 	list_add_tail(&pchild->child_list, &prange->child_list);
1089 }
1090 
1091 /**
1092  * svm_range_split_by_granularity - collect ranges within granularity boundary
1093  *
1094  * @p: the process with svms list
1095  * @mm: mm structure
1096  * @addr: the vm fault address in pages, to split the prange
1097  * @parent: parent range if prange is from child list
1098  * @prange: prange to split
1099  *
1100  * Trims @prange to be a single aligned block of prange->granularity if
1101  * possible. The head and tail are added to the child_list in @parent.
1102  *
1103  * Context: caller must hold mmap_read_lock and prange->lock
1104  *
1105  * Return:
1106  * 0 - OK, otherwise error code
1107  */
1108 int
1109 svm_range_split_by_granularity(struct kfd_process *p, struct mm_struct *mm,
1110 			       unsigned long addr, struct svm_range *parent,
1111 			       struct svm_range *prange)
1112 {
1113 	struct svm_range *head, *tail;
1114 	unsigned long start, last, size;
1115 	int r;
1116 
1117 	/* Align splited range start and size to granularity size, then a single
1118 	 * PTE will be used for whole range, this reduces the number of PTE
1119 	 * updated and the L1 TLB space used for translation.
1120 	 */
1121 	size = 1UL << prange->granularity;
1122 	start = ALIGN_DOWN(addr, size);
1123 	last = ALIGN(addr + 1, size) - 1;
1124 
1125 	pr_debug("svms 0x%p split [0x%lx 0x%lx] to [0x%lx 0x%lx] size 0x%lx\n",
1126 		 prange->svms, prange->start, prange->last, start, last, size);
1127 
1128 	if (start > prange->start) {
1129 		r = svm_range_split(prange, start, prange->last, &head);
1130 		if (r)
1131 			return r;
1132 		svm_range_add_child(parent, mm, head, SVM_OP_ADD_RANGE);
1133 	}
1134 
1135 	if (last < prange->last) {
1136 		r = svm_range_split(prange, prange->start, last, &tail);
1137 		if (r)
1138 			return r;
1139 		svm_range_add_child(parent, mm, tail, SVM_OP_ADD_RANGE);
1140 	}
1141 
1142 	/* xnack on, update mapping on GPUs with ACCESS_IN_PLACE */
1143 	if (p->xnack_enabled && prange->work_item.op == SVM_OP_ADD_RANGE) {
1144 		prange->work_item.op = SVM_OP_ADD_RANGE_AND_MAP;
1145 		pr_debug("change prange 0x%p [0x%lx 0x%lx] op %d\n",
1146 			 prange, prange->start, prange->last,
1147 			 SVM_OP_ADD_RANGE_AND_MAP);
1148 	}
1149 	return 0;
1150 }
1151 
1152 static uint64_t
1153 svm_range_get_pte_flags(struct amdgpu_device *adev, struct svm_range *prange,
1154 			int domain)
1155 {
1156 	struct amdgpu_device *bo_adev;
1157 	uint32_t flags = prange->flags;
1158 	uint32_t mapping_flags = 0;
1159 	uint64_t pte_flags;
1160 	bool snoop = (domain != SVM_RANGE_VRAM_DOMAIN);
1161 	bool coherent = flags & KFD_IOCTL_SVM_FLAG_COHERENT;
1162 
1163 	if (domain == SVM_RANGE_VRAM_DOMAIN)
1164 		bo_adev = amdgpu_ttm_adev(prange->svm_bo->bo->tbo.bdev);
1165 
1166 	switch (KFD_GC_VERSION(adev->kfd.dev)) {
1167 	case IP_VERSION(9, 4, 1):
1168 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1169 			if (bo_adev == adev) {
1170 				mapping_flags |= coherent ?
1171 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1172 			} else {
1173 				mapping_flags |= coherent ?
1174 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1175 				if (amdgpu_xgmi_same_hive(adev, bo_adev))
1176 					snoop = true;
1177 			}
1178 		} else {
1179 			mapping_flags |= coherent ?
1180 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1181 		}
1182 		break;
1183 	case IP_VERSION(9, 4, 2):
1184 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1185 			if (bo_adev == adev) {
1186 				mapping_flags |= coherent ?
1187 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1188 				if (adev->gmc.xgmi.connected_to_cpu)
1189 					snoop = true;
1190 			} else {
1191 				mapping_flags |= coherent ?
1192 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1193 				if (amdgpu_xgmi_same_hive(adev, bo_adev))
1194 					snoop = true;
1195 			}
1196 		} else {
1197 			mapping_flags |= coherent ?
1198 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1199 		}
1200 		break;
1201 	default:
1202 		mapping_flags |= coherent ?
1203 			AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1204 	}
1205 
1206 	mapping_flags |= AMDGPU_VM_PAGE_READABLE | AMDGPU_VM_PAGE_WRITEABLE;
1207 
1208 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_RO)
1209 		mapping_flags &= ~AMDGPU_VM_PAGE_WRITEABLE;
1210 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_EXEC)
1211 		mapping_flags |= AMDGPU_VM_PAGE_EXECUTABLE;
1212 
1213 	pte_flags = AMDGPU_PTE_VALID;
1214 	pte_flags |= (domain == SVM_RANGE_VRAM_DOMAIN) ? 0 : AMDGPU_PTE_SYSTEM;
1215 	pte_flags |= snoop ? AMDGPU_PTE_SNOOPED : 0;
1216 
1217 	pte_flags |= amdgpu_gem_va_map_flags(adev, mapping_flags);
1218 	return pte_flags;
1219 }
1220 
1221 static int
1222 svm_range_unmap_from_gpu(struct amdgpu_device *adev, struct amdgpu_vm *vm,
1223 			 uint64_t start, uint64_t last,
1224 			 struct dma_fence **fence)
1225 {
1226 	uint64_t init_pte_value = 0;
1227 
1228 	pr_debug("[0x%llx 0x%llx]\n", start, last);
1229 
1230 	return amdgpu_vm_update_range(adev, vm, false, true, true, NULL, start,
1231 				      last, init_pte_value, 0, 0, NULL, NULL,
1232 				      fence);
1233 }
1234 
1235 static int
1236 svm_range_unmap_from_gpus(struct svm_range *prange, unsigned long start,
1237 			  unsigned long last, uint32_t trigger)
1238 {
1239 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1240 	struct kfd_process_device *pdd;
1241 	struct dma_fence *fence = NULL;
1242 	struct kfd_process *p;
1243 	uint32_t gpuidx;
1244 	int r = 0;
1245 
1246 	if (!prange->mapped_to_gpu) {
1247 		pr_debug("prange 0x%p [0x%lx 0x%lx] not mapped to GPU\n",
1248 			 prange, prange->start, prange->last);
1249 		return 0;
1250 	}
1251 
1252 	if (prange->start == start && prange->last == last) {
1253 		pr_debug("unmap svms 0x%p prange 0x%p\n", prange->svms, prange);
1254 		prange->mapped_to_gpu = false;
1255 	}
1256 
1257 	bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
1258 		  MAX_GPU_INSTANCE);
1259 	p = container_of(prange->svms, struct kfd_process, svms);
1260 
1261 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1262 		pr_debug("unmap from gpu idx 0x%x\n", gpuidx);
1263 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1264 		if (!pdd) {
1265 			pr_debug("failed to find device idx %d\n", gpuidx);
1266 			return -EINVAL;
1267 		}
1268 
1269 		kfd_smi_event_unmap_from_gpu(pdd->dev, p->lead_thread->pid,
1270 					     start, last, trigger);
1271 
1272 		r = svm_range_unmap_from_gpu(pdd->dev->adev,
1273 					     drm_priv_to_vm(pdd->drm_priv),
1274 					     start, last, &fence);
1275 		if (r)
1276 			break;
1277 
1278 		if (fence) {
1279 			r = dma_fence_wait(fence, false);
1280 			dma_fence_put(fence);
1281 			fence = NULL;
1282 			if (r)
1283 				break;
1284 		}
1285 		kfd_flush_tlb(pdd, TLB_FLUSH_HEAVYWEIGHT);
1286 	}
1287 
1288 	return r;
1289 }
1290 
1291 static int
1292 svm_range_map_to_gpu(struct kfd_process_device *pdd, struct svm_range *prange,
1293 		     unsigned long offset, unsigned long npages, bool readonly,
1294 		     dma_addr_t *dma_addr, struct amdgpu_device *bo_adev,
1295 		     struct dma_fence **fence, bool flush_tlb)
1296 {
1297 	struct amdgpu_device *adev = pdd->dev->adev;
1298 	struct amdgpu_vm *vm = drm_priv_to_vm(pdd->drm_priv);
1299 	uint64_t pte_flags;
1300 	unsigned long last_start;
1301 	int last_domain;
1302 	int r = 0;
1303 	int64_t i, j;
1304 
1305 	last_start = prange->start + offset;
1306 
1307 	pr_debug("svms 0x%p [0x%lx 0x%lx] readonly %d\n", prange->svms,
1308 		 last_start, last_start + npages - 1, readonly);
1309 
1310 	for (i = offset; i < offset + npages; i++) {
1311 		last_domain = dma_addr[i] & SVM_RANGE_VRAM_DOMAIN;
1312 		dma_addr[i] &= ~SVM_RANGE_VRAM_DOMAIN;
1313 
1314 		/* Collect all pages in the same address range and memory domain
1315 		 * that can be mapped with a single call to update mapping.
1316 		 */
1317 		if (i < offset + npages - 1 &&
1318 		    last_domain == (dma_addr[i + 1] & SVM_RANGE_VRAM_DOMAIN))
1319 			continue;
1320 
1321 		pr_debug("Mapping range [0x%lx 0x%llx] on domain: %s\n",
1322 			 last_start, prange->start + i, last_domain ? "GPU" : "CPU");
1323 
1324 		pte_flags = svm_range_get_pte_flags(adev, prange, last_domain);
1325 		if (readonly)
1326 			pte_flags &= ~AMDGPU_PTE_WRITEABLE;
1327 
1328 		pr_debug("svms 0x%p map [0x%lx 0x%llx] vram %d PTE 0x%llx\n",
1329 			 prange->svms, last_start, prange->start + i,
1330 			 (last_domain == SVM_RANGE_VRAM_DOMAIN) ? 1 : 0,
1331 			 pte_flags);
1332 
1333 		r = amdgpu_vm_update_range(adev, vm, false, false, flush_tlb, NULL,
1334 					   last_start, prange->start + i,
1335 					   pte_flags,
1336 					   (last_start - prange->start) << PAGE_SHIFT,
1337 					   bo_adev ? bo_adev->vm_manager.vram_base_offset : 0,
1338 					   NULL, dma_addr, &vm->last_update);
1339 
1340 		for (j = last_start - prange->start; j <= i; j++)
1341 			dma_addr[j] |= last_domain;
1342 
1343 		if (r) {
1344 			pr_debug("failed %d to map to gpu 0x%lx\n", r, prange->start);
1345 			goto out;
1346 		}
1347 		last_start = prange->start + i + 1;
1348 	}
1349 
1350 	r = amdgpu_vm_update_pdes(adev, vm, false);
1351 	if (r) {
1352 		pr_debug("failed %d to update directories 0x%lx\n", r,
1353 			 prange->start);
1354 		goto out;
1355 	}
1356 
1357 	if (fence)
1358 		*fence = dma_fence_get(vm->last_update);
1359 
1360 out:
1361 	return r;
1362 }
1363 
1364 static int
1365 svm_range_map_to_gpus(struct svm_range *prange, unsigned long offset,
1366 		      unsigned long npages, bool readonly,
1367 		      unsigned long *bitmap, bool wait, bool flush_tlb)
1368 {
1369 	struct kfd_process_device *pdd;
1370 	struct amdgpu_device *bo_adev;
1371 	struct kfd_process *p;
1372 	struct dma_fence *fence = NULL;
1373 	uint32_t gpuidx;
1374 	int r = 0;
1375 
1376 	if (prange->svm_bo && prange->ttm_res)
1377 		bo_adev = amdgpu_ttm_adev(prange->svm_bo->bo->tbo.bdev);
1378 	else
1379 		bo_adev = NULL;
1380 
1381 	p = container_of(prange->svms, struct kfd_process, svms);
1382 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1383 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
1384 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1385 		if (!pdd) {
1386 			pr_debug("failed to find device idx %d\n", gpuidx);
1387 			return -EINVAL;
1388 		}
1389 
1390 		pdd = kfd_bind_process_to_device(pdd->dev, p);
1391 		if (IS_ERR(pdd))
1392 			return -EINVAL;
1393 
1394 		if (bo_adev && pdd->dev->adev != bo_adev &&
1395 		    !amdgpu_xgmi_same_hive(pdd->dev->adev, bo_adev)) {
1396 			pr_debug("cannot map to device idx %d\n", gpuidx);
1397 			continue;
1398 		}
1399 
1400 		r = svm_range_map_to_gpu(pdd, prange, offset, npages, readonly,
1401 					 prange->dma_addr[gpuidx],
1402 					 bo_adev, wait ? &fence : NULL,
1403 					 flush_tlb);
1404 		if (r)
1405 			break;
1406 
1407 		if (fence) {
1408 			r = dma_fence_wait(fence, false);
1409 			dma_fence_put(fence);
1410 			fence = NULL;
1411 			if (r) {
1412 				pr_debug("failed %d to dma fence wait\n", r);
1413 				break;
1414 			}
1415 		}
1416 
1417 		kfd_flush_tlb(pdd, TLB_FLUSH_LEGACY);
1418 	}
1419 
1420 	return r;
1421 }
1422 
1423 struct svm_validate_context {
1424 	struct kfd_process *process;
1425 	struct svm_range *prange;
1426 	bool intr;
1427 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1428 	struct ttm_validate_buffer tv[MAX_GPU_INSTANCE];
1429 	struct list_head validate_list;
1430 	struct ww_acquire_ctx ticket;
1431 };
1432 
1433 static int svm_range_reserve_bos(struct svm_validate_context *ctx)
1434 {
1435 	struct kfd_process_device *pdd;
1436 	struct amdgpu_vm *vm;
1437 	uint32_t gpuidx;
1438 	int r;
1439 
1440 	INIT_LIST_HEAD(&ctx->validate_list);
1441 	for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1442 		pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1443 		if (!pdd) {
1444 			pr_debug("failed to find device idx %d\n", gpuidx);
1445 			return -EINVAL;
1446 		}
1447 		vm = drm_priv_to_vm(pdd->drm_priv);
1448 
1449 		ctx->tv[gpuidx].bo = &vm->root.bo->tbo;
1450 		ctx->tv[gpuidx].num_shared = 4;
1451 		list_add(&ctx->tv[gpuidx].head, &ctx->validate_list);
1452 	}
1453 
1454 	r = ttm_eu_reserve_buffers(&ctx->ticket, &ctx->validate_list,
1455 				   ctx->intr, NULL);
1456 	if (r) {
1457 		pr_debug("failed %d to reserve bo\n", r);
1458 		return r;
1459 	}
1460 
1461 	for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1462 		pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1463 		if (!pdd) {
1464 			pr_debug("failed to find device idx %d\n", gpuidx);
1465 			r = -EINVAL;
1466 			goto unreserve_out;
1467 		}
1468 
1469 		r = amdgpu_vm_validate_pt_bos(pdd->dev->adev,
1470 					      drm_priv_to_vm(pdd->drm_priv),
1471 					      svm_range_bo_validate, NULL);
1472 		if (r) {
1473 			pr_debug("failed %d validate pt bos\n", r);
1474 			goto unreserve_out;
1475 		}
1476 	}
1477 
1478 	return 0;
1479 
1480 unreserve_out:
1481 	ttm_eu_backoff_reservation(&ctx->ticket, &ctx->validate_list);
1482 	return r;
1483 }
1484 
1485 static void svm_range_unreserve_bos(struct svm_validate_context *ctx)
1486 {
1487 	ttm_eu_backoff_reservation(&ctx->ticket, &ctx->validate_list);
1488 }
1489 
1490 static void *kfd_svm_page_owner(struct kfd_process *p, int32_t gpuidx)
1491 {
1492 	struct kfd_process_device *pdd;
1493 
1494 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1495 
1496 	return SVM_ADEV_PGMAP_OWNER(pdd->dev->adev);
1497 }
1498 
1499 /*
1500  * Validation+GPU mapping with concurrent invalidation (MMU notifiers)
1501  *
1502  * To prevent concurrent destruction or change of range attributes, the
1503  * svm_read_lock must be held. The caller must not hold the svm_write_lock
1504  * because that would block concurrent evictions and lead to deadlocks. To
1505  * serialize concurrent migrations or validations of the same range, the
1506  * prange->migrate_mutex must be held.
1507  *
1508  * For VRAM ranges, the SVM BO must be allocated and valid (protected by its
1509  * eviction fence.
1510  *
1511  * The following sequence ensures race-free validation and GPU mapping:
1512  *
1513  * 1. Reserve page table (and SVM BO if range is in VRAM)
1514  * 2. hmm_range_fault to get page addresses (if system memory)
1515  * 3. DMA-map pages (if system memory)
1516  * 4-a. Take notifier lock
1517  * 4-b. Check that pages still valid (mmu_interval_read_retry)
1518  * 4-c. Check that the range was not split or otherwise invalidated
1519  * 4-d. Update GPU page table
1520  * 4.e. Release notifier lock
1521  * 5. Release page table (and SVM BO) reservation
1522  */
1523 static int svm_range_validate_and_map(struct mm_struct *mm,
1524 				      struct svm_range *prange, int32_t gpuidx,
1525 				      bool intr, bool wait, bool flush_tlb)
1526 {
1527 	struct svm_validate_context ctx;
1528 	unsigned long start, end, addr;
1529 	struct kfd_process *p;
1530 	void *owner;
1531 	int32_t idx;
1532 	int r = 0;
1533 
1534 	ctx.process = container_of(prange->svms, struct kfd_process, svms);
1535 	ctx.prange = prange;
1536 	ctx.intr = intr;
1537 
1538 	if (gpuidx < MAX_GPU_INSTANCE) {
1539 		bitmap_zero(ctx.bitmap, MAX_GPU_INSTANCE);
1540 		bitmap_set(ctx.bitmap, gpuidx, 1);
1541 	} else if (ctx.process->xnack_enabled) {
1542 		bitmap_copy(ctx.bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
1543 
1544 		/* If prefetch range to GPU, or GPU retry fault migrate range to
1545 		 * GPU, which has ACCESS attribute to the range, create mapping
1546 		 * on that GPU.
1547 		 */
1548 		if (prange->actual_loc) {
1549 			gpuidx = kfd_process_gpuidx_from_gpuid(ctx.process,
1550 							prange->actual_loc);
1551 			if (gpuidx < 0) {
1552 				WARN_ONCE(1, "failed get device by id 0x%x\n",
1553 					 prange->actual_loc);
1554 				return -EINVAL;
1555 			}
1556 			if (test_bit(gpuidx, prange->bitmap_access))
1557 				bitmap_set(ctx.bitmap, gpuidx, 1);
1558 		}
1559 	} else {
1560 		bitmap_or(ctx.bitmap, prange->bitmap_access,
1561 			  prange->bitmap_aip, MAX_GPU_INSTANCE);
1562 	}
1563 
1564 	if (bitmap_empty(ctx.bitmap, MAX_GPU_INSTANCE)) {
1565 		if (!prange->mapped_to_gpu)
1566 			return 0;
1567 
1568 		bitmap_copy(ctx.bitmap, prange->bitmap_access, MAX_GPU_INSTANCE);
1569 	}
1570 
1571 	if (prange->actual_loc && !prange->ttm_res) {
1572 		/* This should never happen. actual_loc gets set by
1573 		 * svm_migrate_ram_to_vram after allocating a BO.
1574 		 */
1575 		WARN_ONCE(1, "VRAM BO missing during validation\n");
1576 		return -EINVAL;
1577 	}
1578 
1579 	svm_range_reserve_bos(&ctx);
1580 
1581 	p = container_of(prange->svms, struct kfd_process, svms);
1582 	owner = kfd_svm_page_owner(p, find_first_bit(ctx.bitmap,
1583 						MAX_GPU_INSTANCE));
1584 	for_each_set_bit(idx, ctx.bitmap, MAX_GPU_INSTANCE) {
1585 		if (kfd_svm_page_owner(p, idx) != owner) {
1586 			owner = NULL;
1587 			break;
1588 		}
1589 	}
1590 
1591 	start = prange->start << PAGE_SHIFT;
1592 	end = (prange->last + 1) << PAGE_SHIFT;
1593 	for (addr = start; addr < end && !r; ) {
1594 		struct hmm_range *hmm_range;
1595 		struct vm_area_struct *vma;
1596 		unsigned long next;
1597 		unsigned long offset;
1598 		unsigned long npages;
1599 		bool readonly;
1600 
1601 		vma = vma_lookup(mm, addr);
1602 		if (!vma) {
1603 			r = -EFAULT;
1604 			goto unreserve_out;
1605 		}
1606 		readonly = !(vma->vm_flags & VM_WRITE);
1607 
1608 		next = min(vma->vm_end, end);
1609 		npages = (next - addr) >> PAGE_SHIFT;
1610 		WRITE_ONCE(p->svms.faulting_task, current);
1611 		r = amdgpu_hmm_range_get_pages(&prange->notifier, addr, npages,
1612 					       readonly, owner, NULL,
1613 					       &hmm_range);
1614 		WRITE_ONCE(p->svms.faulting_task, NULL);
1615 		if (r) {
1616 			pr_debug("failed %d to get svm range pages\n", r);
1617 			goto unreserve_out;
1618 		}
1619 
1620 		offset = (addr - start) >> PAGE_SHIFT;
1621 		r = svm_range_dma_map(prange, ctx.bitmap, offset, npages,
1622 				      hmm_range->hmm_pfns);
1623 		if (r) {
1624 			pr_debug("failed %d to dma map range\n", r);
1625 			goto unreserve_out;
1626 		}
1627 
1628 		svm_range_lock(prange);
1629 		if (amdgpu_hmm_range_get_pages_done(hmm_range)) {
1630 			pr_debug("hmm update the range, need validate again\n");
1631 			r = -EAGAIN;
1632 			goto unlock_out;
1633 		}
1634 		if (!list_empty(&prange->child_list)) {
1635 			pr_debug("range split by unmap in parallel, validate again\n");
1636 			r = -EAGAIN;
1637 			goto unlock_out;
1638 		}
1639 
1640 		r = svm_range_map_to_gpus(prange, offset, npages, readonly,
1641 					  ctx.bitmap, wait, flush_tlb);
1642 
1643 unlock_out:
1644 		svm_range_unlock(prange);
1645 
1646 		addr = next;
1647 	}
1648 
1649 	if (addr == end) {
1650 		prange->validated_once = true;
1651 		prange->mapped_to_gpu = true;
1652 	}
1653 
1654 unreserve_out:
1655 	svm_range_unreserve_bos(&ctx);
1656 
1657 	if (!r)
1658 		prange->validate_timestamp = ktime_get_boottime();
1659 
1660 	return r;
1661 }
1662 
1663 /**
1664  * svm_range_list_lock_and_flush_work - flush pending deferred work
1665  *
1666  * @svms: the svm range list
1667  * @mm: the mm structure
1668  *
1669  * Context: Returns with mmap write lock held, pending deferred work flushed
1670  *
1671  */
1672 void
1673 svm_range_list_lock_and_flush_work(struct svm_range_list *svms,
1674 				   struct mm_struct *mm)
1675 {
1676 retry_flush_work:
1677 	flush_work(&svms->deferred_list_work);
1678 	mmap_write_lock(mm);
1679 
1680 	if (list_empty(&svms->deferred_range_list))
1681 		return;
1682 	mmap_write_unlock(mm);
1683 	pr_debug("retry flush\n");
1684 	goto retry_flush_work;
1685 }
1686 
1687 static void svm_range_restore_work(struct work_struct *work)
1688 {
1689 	struct delayed_work *dwork = to_delayed_work(work);
1690 	struct amdkfd_process_info *process_info;
1691 	struct svm_range_list *svms;
1692 	struct svm_range *prange;
1693 	struct kfd_process *p;
1694 	struct mm_struct *mm;
1695 	int evicted_ranges;
1696 	int invalid;
1697 	int r;
1698 
1699 	svms = container_of(dwork, struct svm_range_list, restore_work);
1700 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1701 	if (!evicted_ranges)
1702 		return;
1703 
1704 	pr_debug("restore svm ranges\n");
1705 
1706 	p = container_of(svms, struct kfd_process, svms);
1707 	process_info = p->kgd_process_info;
1708 
1709 	/* Keep mm reference when svm_range_validate_and_map ranges */
1710 	mm = get_task_mm(p->lead_thread);
1711 	if (!mm) {
1712 		pr_debug("svms 0x%p process mm gone\n", svms);
1713 		return;
1714 	}
1715 
1716 	mutex_lock(&process_info->lock);
1717 	svm_range_list_lock_and_flush_work(svms, mm);
1718 	mutex_lock(&svms->lock);
1719 
1720 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1721 
1722 	list_for_each_entry(prange, &svms->list, list) {
1723 		invalid = atomic_read(&prange->invalid);
1724 		if (!invalid)
1725 			continue;
1726 
1727 		pr_debug("restoring svms 0x%p prange 0x%p [0x%lx %lx] inv %d\n",
1728 			 prange->svms, prange, prange->start, prange->last,
1729 			 invalid);
1730 
1731 		/*
1732 		 * If range is migrating, wait for migration is done.
1733 		 */
1734 		mutex_lock(&prange->migrate_mutex);
1735 
1736 		r = svm_range_validate_and_map(mm, prange, MAX_GPU_INSTANCE,
1737 					       false, true, false);
1738 		if (r)
1739 			pr_debug("failed %d to map 0x%lx to gpus\n", r,
1740 				 prange->start);
1741 
1742 		mutex_unlock(&prange->migrate_mutex);
1743 		if (r)
1744 			goto out_reschedule;
1745 
1746 		if (atomic_cmpxchg(&prange->invalid, invalid, 0) != invalid)
1747 			goto out_reschedule;
1748 	}
1749 
1750 	if (atomic_cmpxchg(&svms->evicted_ranges, evicted_ranges, 0) !=
1751 	    evicted_ranges)
1752 		goto out_reschedule;
1753 
1754 	evicted_ranges = 0;
1755 
1756 	r = kgd2kfd_resume_mm(mm);
1757 	if (r) {
1758 		/* No recovery from this failure. Probably the CP is
1759 		 * hanging. No point trying again.
1760 		 */
1761 		pr_debug("failed %d to resume KFD\n", r);
1762 	}
1763 
1764 	pr_debug("restore svm ranges successfully\n");
1765 
1766 out_reschedule:
1767 	mutex_unlock(&svms->lock);
1768 	mmap_write_unlock(mm);
1769 	mutex_unlock(&process_info->lock);
1770 
1771 	/* If validation failed, reschedule another attempt */
1772 	if (evicted_ranges) {
1773 		pr_debug("reschedule to restore svm range\n");
1774 		schedule_delayed_work(&svms->restore_work,
1775 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1776 
1777 		kfd_smi_event_queue_restore_rescheduled(mm);
1778 	}
1779 	mmput(mm);
1780 }
1781 
1782 /**
1783  * svm_range_evict - evict svm range
1784  * @prange: svm range structure
1785  * @mm: current process mm_struct
1786  * @start: starting process queue number
1787  * @last: last process queue number
1788  *
1789  * Stop all queues of the process to ensure GPU doesn't access the memory, then
1790  * return to let CPU evict the buffer and proceed CPU pagetable update.
1791  *
1792  * Don't need use lock to sync cpu pagetable invalidation with GPU execution.
1793  * If invalidation happens while restore work is running, restore work will
1794  * restart to ensure to get the latest CPU pages mapping to GPU, then start
1795  * the queues.
1796  */
1797 static int
1798 svm_range_evict(struct svm_range *prange, struct mm_struct *mm,
1799 		unsigned long start, unsigned long last,
1800 		enum mmu_notifier_event event)
1801 {
1802 	struct svm_range_list *svms = prange->svms;
1803 	struct svm_range *pchild;
1804 	struct kfd_process *p;
1805 	int r = 0;
1806 
1807 	p = container_of(svms, struct kfd_process, svms);
1808 
1809 	pr_debug("invalidate svms 0x%p prange [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
1810 		 svms, prange->start, prange->last, start, last);
1811 
1812 	if (!p->xnack_enabled ||
1813 	    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) {
1814 		int evicted_ranges;
1815 		bool mapped = prange->mapped_to_gpu;
1816 
1817 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1818 			if (!pchild->mapped_to_gpu)
1819 				continue;
1820 			mapped = true;
1821 			mutex_lock_nested(&pchild->lock, 1);
1822 			if (pchild->start <= last && pchild->last >= start) {
1823 				pr_debug("increment pchild invalid [0x%lx 0x%lx]\n",
1824 					 pchild->start, pchild->last);
1825 				atomic_inc(&pchild->invalid);
1826 			}
1827 			mutex_unlock(&pchild->lock);
1828 		}
1829 
1830 		if (!mapped)
1831 			return r;
1832 
1833 		if (prange->start <= last && prange->last >= start)
1834 			atomic_inc(&prange->invalid);
1835 
1836 		evicted_ranges = atomic_inc_return(&svms->evicted_ranges);
1837 		if (evicted_ranges != 1)
1838 			return r;
1839 
1840 		pr_debug("evicting svms 0x%p range [0x%lx 0x%lx]\n",
1841 			 prange->svms, prange->start, prange->last);
1842 
1843 		/* First eviction, stop the queues */
1844 		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_SVM);
1845 		if (r)
1846 			pr_debug("failed to quiesce KFD\n");
1847 
1848 		pr_debug("schedule to restore svm %p ranges\n", svms);
1849 		schedule_delayed_work(&svms->restore_work,
1850 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1851 	} else {
1852 		unsigned long s, l;
1853 		uint32_t trigger;
1854 
1855 		if (event == MMU_NOTIFY_MIGRATE)
1856 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY_MIGRATE;
1857 		else
1858 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY;
1859 
1860 		pr_debug("invalidate unmap svms 0x%p [0x%lx 0x%lx] from GPUs\n",
1861 			 prange->svms, start, last);
1862 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1863 			mutex_lock_nested(&pchild->lock, 1);
1864 			s = max(start, pchild->start);
1865 			l = min(last, pchild->last);
1866 			if (l >= s)
1867 				svm_range_unmap_from_gpus(pchild, s, l, trigger);
1868 			mutex_unlock(&pchild->lock);
1869 		}
1870 		s = max(start, prange->start);
1871 		l = min(last, prange->last);
1872 		if (l >= s)
1873 			svm_range_unmap_from_gpus(prange, s, l, trigger);
1874 	}
1875 
1876 	return r;
1877 }
1878 
1879 static struct svm_range *svm_range_clone(struct svm_range *old)
1880 {
1881 	struct svm_range *new;
1882 
1883 	new = svm_range_new(old->svms, old->start, old->last, false);
1884 	if (!new)
1885 		return NULL;
1886 
1887 	if (old->svm_bo) {
1888 		new->ttm_res = old->ttm_res;
1889 		new->offset = old->offset;
1890 		new->svm_bo = svm_range_bo_ref(old->svm_bo);
1891 		spin_lock(&new->svm_bo->list_lock);
1892 		list_add(&new->svm_bo_list, &new->svm_bo->range_list);
1893 		spin_unlock(&new->svm_bo->list_lock);
1894 	}
1895 	new->flags = old->flags;
1896 	new->preferred_loc = old->preferred_loc;
1897 	new->prefetch_loc = old->prefetch_loc;
1898 	new->actual_loc = old->actual_loc;
1899 	new->granularity = old->granularity;
1900 	new->mapped_to_gpu = old->mapped_to_gpu;
1901 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
1902 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
1903 
1904 	return new;
1905 }
1906 
1907 void svm_range_set_max_pages(struct amdgpu_device *adev)
1908 {
1909 	uint64_t max_pages;
1910 	uint64_t pages, _pages;
1911 
1912 	/* 1/32 VRAM size in pages */
1913 	pages = adev->gmc.real_vram_size >> 17;
1914 	pages = clamp(pages, 1ULL << 9, 1ULL << 18);
1915 	pages = rounddown_pow_of_two(pages);
1916 	do {
1917 		max_pages = READ_ONCE(max_svm_range_pages);
1918 		_pages = min_not_zero(max_pages, pages);
1919 	} while (cmpxchg(&max_svm_range_pages, max_pages, _pages) != max_pages);
1920 }
1921 
1922 static int
1923 svm_range_split_new(struct svm_range_list *svms, uint64_t start, uint64_t last,
1924 		    uint64_t max_pages, struct list_head *insert_list,
1925 		    struct list_head *update_list)
1926 {
1927 	struct svm_range *prange;
1928 	uint64_t l;
1929 
1930 	pr_debug("max_svm_range_pages 0x%llx adding [0x%llx 0x%llx]\n",
1931 		 max_pages, start, last);
1932 
1933 	while (last >= start) {
1934 		l = min(last, ALIGN_DOWN(start + max_pages, max_pages) - 1);
1935 
1936 		prange = svm_range_new(svms, start, l, true);
1937 		if (!prange)
1938 			return -ENOMEM;
1939 		list_add(&prange->list, insert_list);
1940 		list_add(&prange->update_list, update_list);
1941 
1942 		start = l + 1;
1943 	}
1944 	return 0;
1945 }
1946 
1947 /**
1948  * svm_range_add - add svm range and handle overlap
1949  * @p: the range add to this process svms
1950  * @start: page size aligned
1951  * @size: page size aligned
1952  * @nattr: number of attributes
1953  * @attrs: array of attributes
1954  * @update_list: output, the ranges need validate and update GPU mapping
1955  * @insert_list: output, the ranges need insert to svms
1956  * @remove_list: output, the ranges are replaced and need remove from svms
1957  *
1958  * Check if the virtual address range has overlap with any existing ranges,
1959  * split partly overlapping ranges and add new ranges in the gaps. All changes
1960  * should be applied to the range_list and interval tree transactionally. If
1961  * any range split or allocation fails, the entire update fails. Therefore any
1962  * existing overlapping svm_ranges are cloned and the original svm_ranges left
1963  * unchanged.
1964  *
1965  * If the transaction succeeds, the caller can update and insert clones and
1966  * new ranges, then free the originals.
1967  *
1968  * Otherwise the caller can free the clones and new ranges, while the old
1969  * svm_ranges remain unchanged.
1970  *
1971  * Context: Process context, caller must hold svms->lock
1972  *
1973  * Return:
1974  * 0 - OK, otherwise error code
1975  */
1976 static int
1977 svm_range_add(struct kfd_process *p, uint64_t start, uint64_t size,
1978 	      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
1979 	      struct list_head *update_list, struct list_head *insert_list,
1980 	      struct list_head *remove_list)
1981 {
1982 	unsigned long last = start + size - 1UL;
1983 	struct svm_range_list *svms = &p->svms;
1984 	struct interval_tree_node *node;
1985 	struct svm_range *prange;
1986 	struct svm_range *tmp;
1987 	struct list_head new_list;
1988 	int r = 0;
1989 
1990 	pr_debug("svms 0x%p [0x%llx 0x%lx]\n", &p->svms, start, last);
1991 
1992 	INIT_LIST_HEAD(update_list);
1993 	INIT_LIST_HEAD(insert_list);
1994 	INIT_LIST_HEAD(remove_list);
1995 	INIT_LIST_HEAD(&new_list);
1996 
1997 	node = interval_tree_iter_first(&svms->objects, start, last);
1998 	while (node) {
1999 		struct interval_tree_node *next;
2000 		unsigned long next_start;
2001 
2002 		pr_debug("found overlap node [0x%lx 0x%lx]\n", node->start,
2003 			 node->last);
2004 
2005 		prange = container_of(node, struct svm_range, it_node);
2006 		next = interval_tree_iter_next(node, start, last);
2007 		next_start = min(node->last, last) + 1;
2008 
2009 		if (svm_range_is_same_attrs(p, prange, nattr, attrs)) {
2010 			/* nothing to do */
2011 		} else if (node->start < start || node->last > last) {
2012 			/* node intersects the update range and its attributes
2013 			 * will change. Clone and split it, apply updates only
2014 			 * to the overlapping part
2015 			 */
2016 			struct svm_range *old = prange;
2017 
2018 			prange = svm_range_clone(old);
2019 			if (!prange) {
2020 				r = -ENOMEM;
2021 				goto out;
2022 			}
2023 
2024 			list_add(&old->update_list, remove_list);
2025 			list_add(&prange->list, insert_list);
2026 			list_add(&prange->update_list, update_list);
2027 
2028 			if (node->start < start) {
2029 				pr_debug("change old range start\n");
2030 				r = svm_range_split_head(prange, start,
2031 							 insert_list);
2032 				if (r)
2033 					goto out;
2034 			}
2035 			if (node->last > last) {
2036 				pr_debug("change old range last\n");
2037 				r = svm_range_split_tail(prange, last,
2038 							 insert_list);
2039 				if (r)
2040 					goto out;
2041 			}
2042 		} else {
2043 			/* The node is contained within start..last,
2044 			 * just update it
2045 			 */
2046 			list_add(&prange->update_list, update_list);
2047 		}
2048 
2049 		/* insert a new node if needed */
2050 		if (node->start > start) {
2051 			r = svm_range_split_new(svms, start, node->start - 1,
2052 						READ_ONCE(max_svm_range_pages),
2053 						&new_list, update_list);
2054 			if (r)
2055 				goto out;
2056 		}
2057 
2058 		node = next;
2059 		start = next_start;
2060 	}
2061 
2062 	/* add a final range at the end if needed */
2063 	if (start <= last)
2064 		r = svm_range_split_new(svms, start, last,
2065 					READ_ONCE(max_svm_range_pages),
2066 					&new_list, update_list);
2067 
2068 out:
2069 	if (r) {
2070 		list_for_each_entry_safe(prange, tmp, insert_list, list)
2071 			svm_range_free(prange, false);
2072 		list_for_each_entry_safe(prange, tmp, &new_list, list)
2073 			svm_range_free(prange, true);
2074 	} else {
2075 		list_splice(&new_list, insert_list);
2076 	}
2077 
2078 	return r;
2079 }
2080 
2081 static void
2082 svm_range_update_notifier_and_interval_tree(struct mm_struct *mm,
2083 					    struct svm_range *prange)
2084 {
2085 	unsigned long start;
2086 	unsigned long last;
2087 
2088 	start = prange->notifier.interval_tree.start >> PAGE_SHIFT;
2089 	last = prange->notifier.interval_tree.last >> PAGE_SHIFT;
2090 
2091 	if (prange->start == start && prange->last == last)
2092 		return;
2093 
2094 	pr_debug("up notifier 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
2095 		  prange->svms, prange, start, last, prange->start,
2096 		  prange->last);
2097 
2098 	if (start != 0 && last != 0) {
2099 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
2100 		svm_range_remove_notifier(prange);
2101 	}
2102 	prange->it_node.start = prange->start;
2103 	prange->it_node.last = prange->last;
2104 
2105 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
2106 	svm_range_add_notifier_locked(mm, prange);
2107 }
2108 
2109 static void
2110 svm_range_handle_list_op(struct svm_range_list *svms, struct svm_range *prange,
2111 			 struct mm_struct *mm)
2112 {
2113 	switch (prange->work_item.op) {
2114 	case SVM_OP_NULL:
2115 		pr_debug("NULL OP 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2116 			 svms, prange, prange->start, prange->last);
2117 		break;
2118 	case SVM_OP_UNMAP_RANGE:
2119 		pr_debug("remove 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2120 			 svms, prange, prange->start, prange->last);
2121 		svm_range_unlink(prange);
2122 		svm_range_remove_notifier(prange);
2123 		svm_range_free(prange, true);
2124 		break;
2125 	case SVM_OP_UPDATE_RANGE_NOTIFIER:
2126 		pr_debug("update notifier 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2127 			 svms, prange, prange->start, prange->last);
2128 		svm_range_update_notifier_and_interval_tree(mm, prange);
2129 		break;
2130 	case SVM_OP_UPDATE_RANGE_NOTIFIER_AND_MAP:
2131 		pr_debug("update and map 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2132 			 svms, prange, prange->start, prange->last);
2133 		svm_range_update_notifier_and_interval_tree(mm, prange);
2134 		/* TODO: implement deferred validation and mapping */
2135 		break;
2136 	case SVM_OP_ADD_RANGE:
2137 		pr_debug("add 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms, prange,
2138 			 prange->start, prange->last);
2139 		svm_range_add_to_svms(prange);
2140 		svm_range_add_notifier_locked(mm, prange);
2141 		break;
2142 	case SVM_OP_ADD_RANGE_AND_MAP:
2143 		pr_debug("add and map 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms,
2144 			 prange, prange->start, prange->last);
2145 		svm_range_add_to_svms(prange);
2146 		svm_range_add_notifier_locked(mm, prange);
2147 		/* TODO: implement deferred validation and mapping */
2148 		break;
2149 	default:
2150 		WARN_ONCE(1, "Unknown prange 0x%p work op %d\n", prange,
2151 			 prange->work_item.op);
2152 	}
2153 }
2154 
2155 static void svm_range_drain_retry_fault(struct svm_range_list *svms)
2156 {
2157 	struct kfd_process_device *pdd;
2158 	struct kfd_process *p;
2159 	int drain;
2160 	uint32_t i;
2161 
2162 	p = container_of(svms, struct kfd_process, svms);
2163 
2164 restart:
2165 	drain = atomic_read(&svms->drain_pagefaults);
2166 	if (!drain)
2167 		return;
2168 
2169 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2170 		pdd = p->pdds[i];
2171 		if (!pdd)
2172 			continue;
2173 
2174 		pr_debug("drain retry fault gpu %d svms %p\n", i, svms);
2175 
2176 		amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2177 				pdd->dev->adev->irq.retry_cam_enabled ?
2178 				&pdd->dev->adev->irq.ih :
2179 				&pdd->dev->adev->irq.ih1);
2180 
2181 		if (pdd->dev->adev->irq.retry_cam_enabled)
2182 			amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2183 				&pdd->dev->adev->irq.ih_soft);
2184 
2185 
2186 		pr_debug("drain retry fault gpu %d svms 0x%p done\n", i, svms);
2187 	}
2188 	if (atomic_cmpxchg(&svms->drain_pagefaults, drain, 0) != drain)
2189 		goto restart;
2190 }
2191 
2192 static void svm_range_deferred_list_work(struct work_struct *work)
2193 {
2194 	struct svm_range_list *svms;
2195 	struct svm_range *prange;
2196 	struct mm_struct *mm;
2197 
2198 	svms = container_of(work, struct svm_range_list, deferred_list_work);
2199 	pr_debug("enter svms 0x%p\n", svms);
2200 
2201 	spin_lock(&svms->deferred_list_lock);
2202 	while (!list_empty(&svms->deferred_range_list)) {
2203 		prange = list_first_entry(&svms->deferred_range_list,
2204 					  struct svm_range, deferred_list);
2205 		spin_unlock(&svms->deferred_list_lock);
2206 
2207 		pr_debug("prange 0x%p [0x%lx 0x%lx] op %d\n", prange,
2208 			 prange->start, prange->last, prange->work_item.op);
2209 
2210 		mm = prange->work_item.mm;
2211 retry:
2212 		mmap_write_lock(mm);
2213 
2214 		/* Checking for the need to drain retry faults must be inside
2215 		 * mmap write lock to serialize with munmap notifiers.
2216 		 */
2217 		if (unlikely(atomic_read(&svms->drain_pagefaults))) {
2218 			mmap_write_unlock(mm);
2219 			svm_range_drain_retry_fault(svms);
2220 			goto retry;
2221 		}
2222 
2223 		/* Remove from deferred_list must be inside mmap write lock, for
2224 		 * two race cases:
2225 		 * 1. unmap_from_cpu may change work_item.op and add the range
2226 		 *    to deferred_list again, cause use after free bug.
2227 		 * 2. svm_range_list_lock_and_flush_work may hold mmap write
2228 		 *    lock and continue because deferred_list is empty, but
2229 		 *    deferred_list work is actually waiting for mmap lock.
2230 		 */
2231 		spin_lock(&svms->deferred_list_lock);
2232 		list_del_init(&prange->deferred_list);
2233 		spin_unlock(&svms->deferred_list_lock);
2234 
2235 		mutex_lock(&svms->lock);
2236 		mutex_lock(&prange->migrate_mutex);
2237 		while (!list_empty(&prange->child_list)) {
2238 			struct svm_range *pchild;
2239 
2240 			pchild = list_first_entry(&prange->child_list,
2241 						struct svm_range, child_list);
2242 			pr_debug("child prange 0x%p op %d\n", pchild,
2243 				 pchild->work_item.op);
2244 			list_del_init(&pchild->child_list);
2245 			svm_range_handle_list_op(svms, pchild, mm);
2246 		}
2247 		mutex_unlock(&prange->migrate_mutex);
2248 
2249 		svm_range_handle_list_op(svms, prange, mm);
2250 		mutex_unlock(&svms->lock);
2251 		mmap_write_unlock(mm);
2252 
2253 		/* Pairs with mmget in svm_range_add_list_work */
2254 		mmput(mm);
2255 
2256 		spin_lock(&svms->deferred_list_lock);
2257 	}
2258 	spin_unlock(&svms->deferred_list_lock);
2259 	pr_debug("exit svms 0x%p\n", svms);
2260 }
2261 
2262 void
2263 svm_range_add_list_work(struct svm_range_list *svms, struct svm_range *prange,
2264 			struct mm_struct *mm, enum svm_work_list_ops op)
2265 {
2266 	spin_lock(&svms->deferred_list_lock);
2267 	/* if prange is on the deferred list */
2268 	if (!list_empty(&prange->deferred_list)) {
2269 		pr_debug("update exist prange 0x%p work op %d\n", prange, op);
2270 		WARN_ONCE(prange->work_item.mm != mm, "unmatch mm\n");
2271 		if (op != SVM_OP_NULL &&
2272 		    prange->work_item.op != SVM_OP_UNMAP_RANGE)
2273 			prange->work_item.op = op;
2274 	} else {
2275 		prange->work_item.op = op;
2276 
2277 		/* Pairs with mmput in deferred_list_work */
2278 		mmget(mm);
2279 		prange->work_item.mm = mm;
2280 		list_add_tail(&prange->deferred_list,
2281 			      &prange->svms->deferred_range_list);
2282 		pr_debug("add prange 0x%p [0x%lx 0x%lx] to work list op %d\n",
2283 			 prange, prange->start, prange->last, op);
2284 	}
2285 	spin_unlock(&svms->deferred_list_lock);
2286 }
2287 
2288 void schedule_deferred_list_work(struct svm_range_list *svms)
2289 {
2290 	spin_lock(&svms->deferred_list_lock);
2291 	if (!list_empty(&svms->deferred_range_list))
2292 		schedule_work(&svms->deferred_list_work);
2293 	spin_unlock(&svms->deferred_list_lock);
2294 }
2295 
2296 static void
2297 svm_range_unmap_split(struct mm_struct *mm, struct svm_range *parent,
2298 		      struct svm_range *prange, unsigned long start,
2299 		      unsigned long last)
2300 {
2301 	struct svm_range *head;
2302 	struct svm_range *tail;
2303 
2304 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2305 		pr_debug("prange 0x%p [0x%lx 0x%lx] is already freed\n", prange,
2306 			 prange->start, prange->last);
2307 		return;
2308 	}
2309 	if (start > prange->last || last < prange->start)
2310 		return;
2311 
2312 	head = tail = prange;
2313 	if (start > prange->start)
2314 		svm_range_split(prange, prange->start, start - 1, &tail);
2315 	if (last < tail->last)
2316 		svm_range_split(tail, last + 1, tail->last, &head);
2317 
2318 	if (head != prange && tail != prange) {
2319 		svm_range_add_child(parent, mm, head, SVM_OP_UNMAP_RANGE);
2320 		svm_range_add_child(parent, mm, tail, SVM_OP_ADD_RANGE);
2321 	} else if (tail != prange) {
2322 		svm_range_add_child(parent, mm, tail, SVM_OP_UNMAP_RANGE);
2323 	} else if (head != prange) {
2324 		svm_range_add_child(parent, mm, head, SVM_OP_UNMAP_RANGE);
2325 	} else if (parent != prange) {
2326 		prange->work_item.op = SVM_OP_UNMAP_RANGE;
2327 	}
2328 }
2329 
2330 static void
2331 svm_range_unmap_from_cpu(struct mm_struct *mm, struct svm_range *prange,
2332 			 unsigned long start, unsigned long last)
2333 {
2334 	uint32_t trigger = KFD_SVM_UNMAP_TRIGGER_UNMAP_FROM_CPU;
2335 	struct svm_range_list *svms;
2336 	struct svm_range *pchild;
2337 	struct kfd_process *p;
2338 	unsigned long s, l;
2339 	bool unmap_parent;
2340 
2341 	p = kfd_lookup_process_by_mm(mm);
2342 	if (!p)
2343 		return;
2344 	svms = &p->svms;
2345 
2346 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n", svms,
2347 		 prange, prange->start, prange->last, start, last);
2348 
2349 	/* Make sure pending page faults are drained in the deferred worker
2350 	 * before the range is freed to avoid straggler interrupts on
2351 	 * unmapped memory causing "phantom faults".
2352 	 */
2353 	atomic_inc(&svms->drain_pagefaults);
2354 
2355 	unmap_parent = start <= prange->start && last >= prange->last;
2356 
2357 	list_for_each_entry(pchild, &prange->child_list, child_list) {
2358 		mutex_lock_nested(&pchild->lock, 1);
2359 		s = max(start, pchild->start);
2360 		l = min(last, pchild->last);
2361 		if (l >= s)
2362 			svm_range_unmap_from_gpus(pchild, s, l, trigger);
2363 		svm_range_unmap_split(mm, prange, pchild, start, last);
2364 		mutex_unlock(&pchild->lock);
2365 	}
2366 	s = max(start, prange->start);
2367 	l = min(last, prange->last);
2368 	if (l >= s)
2369 		svm_range_unmap_from_gpus(prange, s, l, trigger);
2370 	svm_range_unmap_split(mm, prange, prange, start, last);
2371 
2372 	if (unmap_parent)
2373 		svm_range_add_list_work(svms, prange, mm, SVM_OP_UNMAP_RANGE);
2374 	else
2375 		svm_range_add_list_work(svms, prange, mm,
2376 					SVM_OP_UPDATE_RANGE_NOTIFIER);
2377 	schedule_deferred_list_work(svms);
2378 
2379 	kfd_unref_process(p);
2380 }
2381 
2382 /**
2383  * svm_range_cpu_invalidate_pagetables - interval notifier callback
2384  * @mni: mmu_interval_notifier struct
2385  * @range: mmu_notifier_range struct
2386  * @cur_seq: value to pass to mmu_interval_set_seq()
2387  *
2388  * If event is MMU_NOTIFY_UNMAP, this is from CPU unmap range, otherwise, it
2389  * is from migration, or CPU page invalidation callback.
2390  *
2391  * For unmap event, unmap range from GPUs, remove prange from svms in a delayed
2392  * work thread, and split prange if only part of prange is unmapped.
2393  *
2394  * For invalidation event, if GPU retry fault is not enabled, evict the queues,
2395  * then schedule svm_range_restore_work to update GPU mapping and resume queues.
2396  * If GPU retry fault is enabled, unmap the svm range from GPU, retry fault will
2397  * update GPU mapping to recover.
2398  *
2399  * Context: mmap lock, notifier_invalidate_start lock are held
2400  *          for invalidate event, prange lock is held if this is from migration
2401  */
2402 static bool
2403 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
2404 				    const struct mmu_notifier_range *range,
2405 				    unsigned long cur_seq)
2406 {
2407 	struct svm_range *prange;
2408 	unsigned long start;
2409 	unsigned long last;
2410 
2411 	if (range->event == MMU_NOTIFY_RELEASE)
2412 		return true;
2413 	if (!mmget_not_zero(mni->mm))
2414 		return true;
2415 
2416 	start = mni->interval_tree.start;
2417 	last = mni->interval_tree.last;
2418 	start = max(start, range->start) >> PAGE_SHIFT;
2419 	last = min(last, range->end - 1) >> PAGE_SHIFT;
2420 	pr_debug("[0x%lx 0x%lx] range[0x%lx 0x%lx] notifier[0x%lx 0x%lx] %d\n",
2421 		 start, last, range->start >> PAGE_SHIFT,
2422 		 (range->end - 1) >> PAGE_SHIFT,
2423 		 mni->interval_tree.start >> PAGE_SHIFT,
2424 		 mni->interval_tree.last >> PAGE_SHIFT, range->event);
2425 
2426 	prange = container_of(mni, struct svm_range, notifier);
2427 
2428 	svm_range_lock(prange);
2429 	mmu_interval_set_seq(mni, cur_seq);
2430 
2431 	switch (range->event) {
2432 	case MMU_NOTIFY_UNMAP:
2433 		svm_range_unmap_from_cpu(mni->mm, prange, start, last);
2434 		break;
2435 	default:
2436 		svm_range_evict(prange, mni->mm, start, last, range->event);
2437 		break;
2438 	}
2439 
2440 	svm_range_unlock(prange);
2441 	mmput(mni->mm);
2442 
2443 	return true;
2444 }
2445 
2446 /**
2447  * svm_range_from_addr - find svm range from fault address
2448  * @svms: svm range list header
2449  * @addr: address to search range interval tree, in pages
2450  * @parent: parent range if range is on child list
2451  *
2452  * Context: The caller must hold svms->lock
2453  *
2454  * Return: the svm_range found or NULL
2455  */
2456 struct svm_range *
2457 svm_range_from_addr(struct svm_range_list *svms, unsigned long addr,
2458 		    struct svm_range **parent)
2459 {
2460 	struct interval_tree_node *node;
2461 	struct svm_range *prange;
2462 	struct svm_range *pchild;
2463 
2464 	node = interval_tree_iter_first(&svms->objects, addr, addr);
2465 	if (!node)
2466 		return NULL;
2467 
2468 	prange = container_of(node, struct svm_range, it_node);
2469 	pr_debug("address 0x%lx prange [0x%lx 0x%lx] node [0x%lx 0x%lx]\n",
2470 		 addr, prange->start, prange->last, node->start, node->last);
2471 
2472 	if (addr >= prange->start && addr <= prange->last) {
2473 		if (parent)
2474 			*parent = prange;
2475 		return prange;
2476 	}
2477 	list_for_each_entry(pchild, &prange->child_list, child_list)
2478 		if (addr >= pchild->start && addr <= pchild->last) {
2479 			pr_debug("found address 0x%lx pchild [0x%lx 0x%lx]\n",
2480 				 addr, pchild->start, pchild->last);
2481 			if (parent)
2482 				*parent = prange;
2483 			return pchild;
2484 		}
2485 
2486 	return NULL;
2487 }
2488 
2489 /* svm_range_best_restore_location - decide the best fault restore location
2490  * @prange: svm range structure
2491  * @adev: the GPU on which vm fault happened
2492  *
2493  * This is only called when xnack is on, to decide the best location to restore
2494  * the range mapping after GPU vm fault. Caller uses the best location to do
2495  * migration if actual loc is not best location, then update GPU page table
2496  * mapping to the best location.
2497  *
2498  * If the preferred loc is accessible by faulting GPU, use preferred loc.
2499  * If vm fault gpu idx is on range ACCESSIBLE bitmap, best_loc is vm fault gpu
2500  * If vm fault gpu idx is on range ACCESSIBLE_IN_PLACE bitmap, then
2501  *    if range actual loc is cpu, best_loc is cpu
2502  *    if vm fault gpu is on xgmi same hive of range actual loc gpu, best_loc is
2503  *    range actual loc.
2504  * Otherwise, GPU no access, best_loc is -1.
2505  *
2506  * Return:
2507  * -1 means vm fault GPU no access
2508  * 0 for CPU or GPU id
2509  */
2510 static int32_t
2511 svm_range_best_restore_location(struct svm_range *prange,
2512 				struct amdgpu_device *adev,
2513 				int32_t *gpuidx)
2514 {
2515 	struct amdgpu_device *bo_adev, *preferred_adev;
2516 	struct kfd_process *p;
2517 	uint32_t gpuid;
2518 	int r;
2519 
2520 	p = container_of(prange->svms, struct kfd_process, svms);
2521 
2522 	r = kfd_process_gpuid_from_adev(p, adev, &gpuid, gpuidx);
2523 	if (r < 0) {
2524 		pr_debug("failed to get gpuid from kgd\n");
2525 		return -1;
2526 	}
2527 
2528 	if (prange->preferred_loc == gpuid ||
2529 	    prange->preferred_loc == KFD_IOCTL_SVM_LOCATION_SYSMEM) {
2530 		return prange->preferred_loc;
2531 	} else if (prange->preferred_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
2532 		preferred_adev = svm_range_get_adev_by_id(prange,
2533 							prange->preferred_loc);
2534 		if (amdgpu_xgmi_same_hive(adev, preferred_adev))
2535 			return prange->preferred_loc;
2536 		/* fall through */
2537 	}
2538 
2539 	if (test_bit(*gpuidx, prange->bitmap_access))
2540 		return gpuid;
2541 
2542 	if (test_bit(*gpuidx, prange->bitmap_aip)) {
2543 		if (!prange->actual_loc)
2544 			return 0;
2545 
2546 		bo_adev = svm_range_get_adev_by_id(prange, prange->actual_loc);
2547 		if (amdgpu_xgmi_same_hive(adev, bo_adev))
2548 			return prange->actual_loc;
2549 		else
2550 			return 0;
2551 	}
2552 
2553 	return -1;
2554 }
2555 
2556 static int
2557 svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
2558 			       unsigned long *start, unsigned long *last,
2559 			       bool *is_heap_stack)
2560 {
2561 	struct vm_area_struct *vma;
2562 	struct interval_tree_node *node;
2563 	unsigned long start_limit, end_limit;
2564 
2565 	vma = vma_lookup(p->mm, addr << PAGE_SHIFT);
2566 	if (!vma) {
2567 		pr_debug("VMA does not exist in address [0x%llx]\n", addr);
2568 		return -EFAULT;
2569 	}
2570 
2571 	*is_heap_stack = (vma->vm_start <= vma->vm_mm->brk &&
2572 			  vma->vm_end >= vma->vm_mm->start_brk) ||
2573 			 (vma->vm_start <= vma->vm_mm->start_stack &&
2574 			  vma->vm_end >= vma->vm_mm->start_stack);
2575 
2576 	start_limit = max(vma->vm_start >> PAGE_SHIFT,
2577 		      (unsigned long)ALIGN_DOWN(addr, 2UL << 8));
2578 	end_limit = min(vma->vm_end >> PAGE_SHIFT,
2579 		    (unsigned long)ALIGN(addr + 1, 2UL << 8));
2580 	/* First range that starts after the fault address */
2581 	node = interval_tree_iter_first(&p->svms.objects, addr + 1, ULONG_MAX);
2582 	if (node) {
2583 		end_limit = min(end_limit, node->start);
2584 		/* Last range that ends before the fault address */
2585 		node = container_of(rb_prev(&node->rb),
2586 				    struct interval_tree_node, rb);
2587 	} else {
2588 		/* Last range must end before addr because
2589 		 * there was no range after addr
2590 		 */
2591 		node = container_of(rb_last(&p->svms.objects.rb_root),
2592 				    struct interval_tree_node, rb);
2593 	}
2594 	if (node) {
2595 		if (node->last >= addr) {
2596 			WARN(1, "Overlap with prev node and page fault addr\n");
2597 			return -EFAULT;
2598 		}
2599 		start_limit = max(start_limit, node->last + 1);
2600 	}
2601 
2602 	*start = start_limit;
2603 	*last = end_limit - 1;
2604 
2605 	pr_debug("vma [0x%lx 0x%lx] range [0x%lx 0x%lx] is_heap_stack %d\n",
2606 		 vma->vm_start >> PAGE_SHIFT, vma->vm_end >> PAGE_SHIFT,
2607 		 *start, *last, *is_heap_stack);
2608 
2609 	return 0;
2610 }
2611 
2612 static int
2613 svm_range_check_vm_userptr(struct kfd_process *p, uint64_t start, uint64_t last,
2614 			   uint64_t *bo_s, uint64_t *bo_l)
2615 {
2616 	struct amdgpu_bo_va_mapping *mapping;
2617 	struct interval_tree_node *node;
2618 	struct amdgpu_bo *bo = NULL;
2619 	unsigned long userptr;
2620 	uint32_t i;
2621 	int r;
2622 
2623 	for (i = 0; i < p->n_pdds; i++) {
2624 		struct amdgpu_vm *vm;
2625 
2626 		if (!p->pdds[i]->drm_priv)
2627 			continue;
2628 
2629 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
2630 		r = amdgpu_bo_reserve(vm->root.bo, false);
2631 		if (r)
2632 			return r;
2633 
2634 		/* Check userptr by searching entire vm->va interval tree */
2635 		node = interval_tree_iter_first(&vm->va, 0, ~0ULL);
2636 		while (node) {
2637 			mapping = container_of((struct rb_node *)node,
2638 					       struct amdgpu_bo_va_mapping, rb);
2639 			bo = mapping->bo_va->base.bo;
2640 
2641 			if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm,
2642 							 start << PAGE_SHIFT,
2643 							 last << PAGE_SHIFT,
2644 							 &userptr)) {
2645 				node = interval_tree_iter_next(node, 0, ~0ULL);
2646 				continue;
2647 			}
2648 
2649 			pr_debug("[0x%llx 0x%llx] already userptr mapped\n",
2650 				 start, last);
2651 			if (bo_s && bo_l) {
2652 				*bo_s = userptr >> PAGE_SHIFT;
2653 				*bo_l = *bo_s + bo->tbo.ttm->num_pages - 1;
2654 			}
2655 			amdgpu_bo_unreserve(vm->root.bo);
2656 			return -EADDRINUSE;
2657 		}
2658 		amdgpu_bo_unreserve(vm->root.bo);
2659 	}
2660 	return 0;
2661 }
2662 
2663 static struct
2664 svm_range *svm_range_create_unregistered_range(struct amdgpu_device *adev,
2665 						struct kfd_process *p,
2666 						struct mm_struct *mm,
2667 						int64_t addr)
2668 {
2669 	struct svm_range *prange = NULL;
2670 	unsigned long start, last;
2671 	uint32_t gpuid, gpuidx;
2672 	bool is_heap_stack;
2673 	uint64_t bo_s = 0;
2674 	uint64_t bo_l = 0;
2675 	int r;
2676 
2677 	if (svm_range_get_range_boundaries(p, addr, &start, &last,
2678 					   &is_heap_stack))
2679 		return NULL;
2680 
2681 	r = svm_range_check_vm(p, start, last, &bo_s, &bo_l);
2682 	if (r != -EADDRINUSE)
2683 		r = svm_range_check_vm_userptr(p, start, last, &bo_s, &bo_l);
2684 
2685 	if (r == -EADDRINUSE) {
2686 		if (addr >= bo_s && addr <= bo_l)
2687 			return NULL;
2688 
2689 		/* Create one page svm range if 2MB range overlapping */
2690 		start = addr;
2691 		last = addr;
2692 	}
2693 
2694 	prange = svm_range_new(&p->svms, start, last, true);
2695 	if (!prange) {
2696 		pr_debug("Failed to create prange in address [0x%llx]\n", addr);
2697 		return NULL;
2698 	}
2699 	if (kfd_process_gpuid_from_adev(p, adev, &gpuid, &gpuidx)) {
2700 		pr_debug("failed to get gpuid from kgd\n");
2701 		svm_range_free(prange, true);
2702 		return NULL;
2703 	}
2704 
2705 	if (is_heap_stack)
2706 		prange->preferred_loc = KFD_IOCTL_SVM_LOCATION_SYSMEM;
2707 
2708 	svm_range_add_to_svms(prange);
2709 	svm_range_add_notifier_locked(mm, prange);
2710 
2711 	return prange;
2712 }
2713 
2714 /* svm_range_skip_recover - decide if prange can be recovered
2715  * @prange: svm range structure
2716  *
2717  * GPU vm retry fault handle skip recover the range for cases:
2718  * 1. prange is on deferred list to be removed after unmap, it is stale fault,
2719  *    deferred list work will drain the stale fault before free the prange.
2720  * 2. prange is on deferred list to add interval notifier after split, or
2721  * 3. prange is child range, it is split from parent prange, recover later
2722  *    after interval notifier is added.
2723  *
2724  * Return: true to skip recover, false to recover
2725  */
2726 static bool svm_range_skip_recover(struct svm_range *prange)
2727 {
2728 	struct svm_range_list *svms = prange->svms;
2729 
2730 	spin_lock(&svms->deferred_list_lock);
2731 	if (list_empty(&prange->deferred_list) &&
2732 	    list_empty(&prange->child_list)) {
2733 		spin_unlock(&svms->deferred_list_lock);
2734 		return false;
2735 	}
2736 	spin_unlock(&svms->deferred_list_lock);
2737 
2738 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2739 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] unmapped\n",
2740 			 svms, prange, prange->start, prange->last);
2741 		return true;
2742 	}
2743 	if (prange->work_item.op == SVM_OP_ADD_RANGE_AND_MAP ||
2744 	    prange->work_item.op == SVM_OP_ADD_RANGE) {
2745 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] not added yet\n",
2746 			 svms, prange, prange->start, prange->last);
2747 		return true;
2748 	}
2749 	return false;
2750 }
2751 
2752 static void
2753 svm_range_count_fault(struct amdgpu_device *adev, struct kfd_process *p,
2754 		      int32_t gpuidx)
2755 {
2756 	struct kfd_process_device *pdd;
2757 
2758 	/* fault is on different page of same range
2759 	 * or fault is skipped to recover later
2760 	 * or fault is on invalid virtual address
2761 	 */
2762 	if (gpuidx == MAX_GPU_INSTANCE) {
2763 		uint32_t gpuid;
2764 		int r;
2765 
2766 		r = kfd_process_gpuid_from_adev(p, adev, &gpuid, &gpuidx);
2767 		if (r < 0)
2768 			return;
2769 	}
2770 
2771 	/* fault is recovered
2772 	 * or fault cannot recover because GPU no access on the range
2773 	 */
2774 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
2775 	if (pdd)
2776 		WRITE_ONCE(pdd->faults, pdd->faults + 1);
2777 }
2778 
2779 static bool
2780 svm_fault_allowed(struct vm_area_struct *vma, bool write_fault)
2781 {
2782 	unsigned long requested = VM_READ;
2783 
2784 	if (write_fault)
2785 		requested |= VM_WRITE;
2786 
2787 	pr_debug("requested 0x%lx, vma permission flags 0x%lx\n", requested,
2788 		vma->vm_flags);
2789 	return (vma->vm_flags & requested) == requested;
2790 }
2791 
2792 int
2793 svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
2794 			uint64_t addr, bool write_fault)
2795 {
2796 	struct mm_struct *mm = NULL;
2797 	struct svm_range_list *svms;
2798 	struct svm_range *prange;
2799 	struct kfd_process *p;
2800 	ktime_t timestamp = ktime_get_boottime();
2801 	int32_t best_loc;
2802 	int32_t gpuidx = MAX_GPU_INSTANCE;
2803 	bool write_locked = false;
2804 	struct vm_area_struct *vma;
2805 	bool migration = false;
2806 	int r = 0;
2807 
2808 	if (!KFD_IS_SVM_API_SUPPORTED(adev->kfd.dev)) {
2809 		pr_debug("device does not support SVM\n");
2810 		return -EFAULT;
2811 	}
2812 
2813 	p = kfd_lookup_process_by_pasid(pasid);
2814 	if (!p) {
2815 		pr_debug("kfd process not founded pasid 0x%x\n", pasid);
2816 		return 0;
2817 	}
2818 	svms = &p->svms;
2819 
2820 	pr_debug("restoring svms 0x%p fault address 0x%llx\n", svms, addr);
2821 
2822 	if (atomic_read(&svms->drain_pagefaults)) {
2823 		pr_debug("draining retry fault, drop fault 0x%llx\n", addr);
2824 		r = 0;
2825 		goto out;
2826 	}
2827 
2828 	if (!p->xnack_enabled) {
2829 		pr_debug("XNACK not enabled for pasid 0x%x\n", pasid);
2830 		r = -EFAULT;
2831 		goto out;
2832 	}
2833 
2834 	/* p->lead_thread is available as kfd_process_wq_release flush the work
2835 	 * before releasing task ref.
2836 	 */
2837 	mm = get_task_mm(p->lead_thread);
2838 	if (!mm) {
2839 		pr_debug("svms 0x%p failed to get mm\n", svms);
2840 		r = 0;
2841 		goto out;
2842 	}
2843 
2844 	mmap_read_lock(mm);
2845 retry_write_locked:
2846 	mutex_lock(&svms->lock);
2847 	prange = svm_range_from_addr(svms, addr, NULL);
2848 	if (!prange) {
2849 		pr_debug("failed to find prange svms 0x%p address [0x%llx]\n",
2850 			 svms, addr);
2851 		if (!write_locked) {
2852 			/* Need the write lock to create new range with MMU notifier.
2853 			 * Also flush pending deferred work to make sure the interval
2854 			 * tree is up to date before we add a new range
2855 			 */
2856 			mutex_unlock(&svms->lock);
2857 			mmap_read_unlock(mm);
2858 			mmap_write_lock(mm);
2859 			write_locked = true;
2860 			goto retry_write_locked;
2861 		}
2862 		prange = svm_range_create_unregistered_range(adev, p, mm, addr);
2863 		if (!prange) {
2864 			pr_debug("failed to create unregistered range svms 0x%p address [0x%llx]\n",
2865 				 svms, addr);
2866 			mmap_write_downgrade(mm);
2867 			r = -EFAULT;
2868 			goto out_unlock_svms;
2869 		}
2870 	}
2871 	if (write_locked)
2872 		mmap_write_downgrade(mm);
2873 
2874 	mutex_lock(&prange->migrate_mutex);
2875 
2876 	if (svm_range_skip_recover(prange)) {
2877 		amdgpu_gmc_filter_faults_remove(adev, addr, pasid);
2878 		r = 0;
2879 		goto out_unlock_range;
2880 	}
2881 
2882 	/* skip duplicate vm fault on different pages of same range */
2883 	if (ktime_before(timestamp, ktime_add_ns(prange->validate_timestamp,
2884 				AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING))) {
2885 		pr_debug("svms 0x%p [0x%lx %lx] already restored\n",
2886 			 svms, prange->start, prange->last);
2887 		r = 0;
2888 		goto out_unlock_range;
2889 	}
2890 
2891 	/* __do_munmap removed VMA, return success as we are handling stale
2892 	 * retry fault.
2893 	 */
2894 	vma = vma_lookup(mm, addr << PAGE_SHIFT);
2895 	if (!vma) {
2896 		pr_debug("address 0x%llx VMA is removed\n", addr);
2897 		r = 0;
2898 		goto out_unlock_range;
2899 	}
2900 
2901 	if (!svm_fault_allowed(vma, write_fault)) {
2902 		pr_debug("fault addr 0x%llx no %s permission\n", addr,
2903 			write_fault ? "write" : "read");
2904 		r = -EPERM;
2905 		goto out_unlock_range;
2906 	}
2907 
2908 	best_loc = svm_range_best_restore_location(prange, adev, &gpuidx);
2909 	if (best_loc == -1) {
2910 		pr_debug("svms %p failed get best restore loc [0x%lx 0x%lx]\n",
2911 			 svms, prange->start, prange->last);
2912 		r = -EACCES;
2913 		goto out_unlock_range;
2914 	}
2915 
2916 	pr_debug("svms %p [0x%lx 0x%lx] best restore 0x%x, actual loc 0x%x\n",
2917 		 svms, prange->start, prange->last, best_loc,
2918 		 prange->actual_loc);
2919 
2920 	kfd_smi_event_page_fault_start(adev->kfd.dev, p->lead_thread->pid, addr,
2921 				       write_fault, timestamp);
2922 
2923 	if (prange->actual_loc != best_loc) {
2924 		migration = true;
2925 		if (best_loc) {
2926 			r = svm_migrate_to_vram(prange, best_loc, mm,
2927 					KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU);
2928 			if (r) {
2929 				pr_debug("svm_migrate_to_vram failed (%d) at %llx, falling back to system memory\n",
2930 					 r, addr);
2931 				/* Fallback to system memory if migration to
2932 				 * VRAM failed
2933 				 */
2934 				if (prange->actual_loc)
2935 					r = svm_migrate_vram_to_ram(prange, mm,
2936 					   KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU,
2937 					   NULL);
2938 				else
2939 					r = 0;
2940 			}
2941 		} else {
2942 			r = svm_migrate_vram_to_ram(prange, mm,
2943 					KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU,
2944 					NULL);
2945 		}
2946 		if (r) {
2947 			pr_debug("failed %d to migrate svms %p [0x%lx 0x%lx]\n",
2948 				 r, svms, prange->start, prange->last);
2949 			goto out_unlock_range;
2950 		}
2951 	}
2952 
2953 	r = svm_range_validate_and_map(mm, prange, gpuidx, false, false, false);
2954 	if (r)
2955 		pr_debug("failed %d to map svms 0x%p [0x%lx 0x%lx] to gpus\n",
2956 			 r, svms, prange->start, prange->last);
2957 
2958 	kfd_smi_event_page_fault_end(adev->kfd.dev, p->lead_thread->pid, addr,
2959 				     migration);
2960 
2961 out_unlock_range:
2962 	mutex_unlock(&prange->migrate_mutex);
2963 out_unlock_svms:
2964 	mutex_unlock(&svms->lock);
2965 	mmap_read_unlock(mm);
2966 
2967 	svm_range_count_fault(adev, p, gpuidx);
2968 
2969 	mmput(mm);
2970 out:
2971 	kfd_unref_process(p);
2972 
2973 	if (r == -EAGAIN) {
2974 		pr_debug("recover vm fault later\n");
2975 		amdgpu_gmc_filter_faults_remove(adev, addr, pasid);
2976 		r = 0;
2977 	}
2978 	return r;
2979 }
2980 
2981 int
2982 svm_range_switch_xnack_reserve_mem(struct kfd_process *p, bool xnack_enabled)
2983 {
2984 	struct svm_range *prange, *pchild;
2985 	uint64_t reserved_size = 0;
2986 	uint64_t size;
2987 	int r = 0;
2988 
2989 	pr_debug("switching xnack from %d to %d\n", p->xnack_enabled, xnack_enabled);
2990 
2991 	mutex_lock(&p->svms.lock);
2992 
2993 	list_for_each_entry(prange, &p->svms.list, list) {
2994 		svm_range_lock(prange);
2995 		list_for_each_entry(pchild, &prange->child_list, child_list) {
2996 			size = (pchild->last - pchild->start + 1) << PAGE_SHIFT;
2997 			if (xnack_enabled) {
2998 				amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
2999 						KFD_IOC_ALLOC_MEM_FLAGS_USERPTR);
3000 			} else {
3001 				r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3002 						KFD_IOC_ALLOC_MEM_FLAGS_USERPTR);
3003 				if (r)
3004 					goto out_unlock;
3005 				reserved_size += size;
3006 			}
3007 		}
3008 
3009 		size = (prange->last - prange->start + 1) << PAGE_SHIFT;
3010 		if (xnack_enabled) {
3011 			amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3012 						KFD_IOC_ALLOC_MEM_FLAGS_USERPTR);
3013 		} else {
3014 			r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3015 						KFD_IOC_ALLOC_MEM_FLAGS_USERPTR);
3016 			if (r)
3017 				goto out_unlock;
3018 			reserved_size += size;
3019 		}
3020 out_unlock:
3021 		svm_range_unlock(prange);
3022 		if (r)
3023 			break;
3024 	}
3025 
3026 	if (r)
3027 		amdgpu_amdkfd_unreserve_mem_limit(NULL, reserved_size,
3028 						KFD_IOC_ALLOC_MEM_FLAGS_USERPTR);
3029 	else
3030 		/* Change xnack mode must be inside svms lock, to avoid race with
3031 		 * svm_range_deferred_list_work unreserve memory in parallel.
3032 		 */
3033 		p->xnack_enabled = xnack_enabled;
3034 
3035 	mutex_unlock(&p->svms.lock);
3036 	return r;
3037 }
3038 
3039 void svm_range_list_fini(struct kfd_process *p)
3040 {
3041 	struct svm_range *prange;
3042 	struct svm_range *next;
3043 
3044 	pr_debug("pasid 0x%x svms 0x%p\n", p->pasid, &p->svms);
3045 
3046 	cancel_delayed_work_sync(&p->svms.restore_work);
3047 
3048 	/* Ensure list work is finished before process is destroyed */
3049 	flush_work(&p->svms.deferred_list_work);
3050 
3051 	/*
3052 	 * Ensure no retry fault comes in afterwards, as page fault handler will
3053 	 * not find kfd process and take mm lock to recover fault.
3054 	 */
3055 	atomic_inc(&p->svms.drain_pagefaults);
3056 	svm_range_drain_retry_fault(&p->svms);
3057 
3058 	list_for_each_entry_safe(prange, next, &p->svms.list, list) {
3059 		svm_range_unlink(prange);
3060 		svm_range_remove_notifier(prange);
3061 		svm_range_free(prange, true);
3062 	}
3063 
3064 	mutex_destroy(&p->svms.lock);
3065 
3066 	pr_debug("pasid 0x%x svms 0x%p done\n", p->pasid, &p->svms);
3067 }
3068 
3069 int svm_range_list_init(struct kfd_process *p)
3070 {
3071 	struct svm_range_list *svms = &p->svms;
3072 	int i;
3073 
3074 	svms->objects = RB_ROOT_CACHED;
3075 	mutex_init(&svms->lock);
3076 	INIT_LIST_HEAD(&svms->list);
3077 	atomic_set(&svms->evicted_ranges, 0);
3078 	atomic_set(&svms->drain_pagefaults, 0);
3079 	INIT_DELAYED_WORK(&svms->restore_work, svm_range_restore_work);
3080 	INIT_WORK(&svms->deferred_list_work, svm_range_deferred_list_work);
3081 	INIT_LIST_HEAD(&svms->deferred_range_list);
3082 	INIT_LIST_HEAD(&svms->criu_svm_metadata_list);
3083 	spin_lock_init(&svms->deferred_list_lock);
3084 
3085 	for (i = 0; i < p->n_pdds; i++)
3086 		if (KFD_IS_SVM_API_SUPPORTED(p->pdds[i]->dev))
3087 			bitmap_set(svms->bitmap_supported, i, 1);
3088 
3089 	return 0;
3090 }
3091 
3092 /**
3093  * svm_range_check_vm - check if virtual address range mapped already
3094  * @p: current kfd_process
3095  * @start: range start address, in pages
3096  * @last: range last address, in pages
3097  * @bo_s: mapping start address in pages if address range already mapped
3098  * @bo_l: mapping last address in pages if address range already mapped
3099  *
3100  * The purpose is to avoid virtual address ranges already allocated by
3101  * kfd_ioctl_alloc_memory_of_gpu ioctl.
3102  * It looks for each pdd in the kfd_process.
3103  *
3104  * Context: Process context
3105  *
3106  * Return 0 - OK, if the range is not mapped.
3107  * Otherwise error code:
3108  * -EADDRINUSE - if address is mapped already by kfd_ioctl_alloc_memory_of_gpu
3109  * -ERESTARTSYS - A wait for the buffer to become unreserved was interrupted by
3110  * a signal. Release all buffer reservations and return to user-space.
3111  */
3112 static int
3113 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
3114 		   uint64_t *bo_s, uint64_t *bo_l)
3115 {
3116 	struct amdgpu_bo_va_mapping *mapping;
3117 	struct interval_tree_node *node;
3118 	uint32_t i;
3119 	int r;
3120 
3121 	for (i = 0; i < p->n_pdds; i++) {
3122 		struct amdgpu_vm *vm;
3123 
3124 		if (!p->pdds[i]->drm_priv)
3125 			continue;
3126 
3127 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
3128 		r = amdgpu_bo_reserve(vm->root.bo, false);
3129 		if (r)
3130 			return r;
3131 
3132 		node = interval_tree_iter_first(&vm->va, start, last);
3133 		if (node) {
3134 			pr_debug("range [0x%llx 0x%llx] already TTM mapped\n",
3135 				 start, last);
3136 			mapping = container_of((struct rb_node *)node,
3137 					       struct amdgpu_bo_va_mapping, rb);
3138 			if (bo_s && bo_l) {
3139 				*bo_s = mapping->start;
3140 				*bo_l = mapping->last;
3141 			}
3142 			amdgpu_bo_unreserve(vm->root.bo);
3143 			return -EADDRINUSE;
3144 		}
3145 		amdgpu_bo_unreserve(vm->root.bo);
3146 	}
3147 
3148 	return 0;
3149 }
3150 
3151 /**
3152  * svm_range_is_valid - check if virtual address range is valid
3153  * @p: current kfd_process
3154  * @start: range start address, in pages
3155  * @size: range size, in pages
3156  *
3157  * Valid virtual address range means it belongs to one or more VMAs
3158  *
3159  * Context: Process context
3160  *
3161  * Return:
3162  *  0 - OK, otherwise error code
3163  */
3164 static int
3165 svm_range_is_valid(struct kfd_process *p, uint64_t start, uint64_t size)
3166 {
3167 	const unsigned long device_vma = VM_IO | VM_PFNMAP | VM_MIXEDMAP;
3168 	struct vm_area_struct *vma;
3169 	unsigned long end;
3170 	unsigned long start_unchg = start;
3171 
3172 	start <<= PAGE_SHIFT;
3173 	end = start + (size << PAGE_SHIFT);
3174 	do {
3175 		vma = vma_lookup(p->mm, start);
3176 		if (!vma || (vma->vm_flags & device_vma))
3177 			return -EFAULT;
3178 		start = min(end, vma->vm_end);
3179 	} while (start < end);
3180 
3181 	return svm_range_check_vm(p, start_unchg, (end - 1) >> PAGE_SHIFT, NULL,
3182 				  NULL);
3183 }
3184 
3185 /**
3186  * svm_range_best_prefetch_location - decide the best prefetch location
3187  * @prange: svm range structure
3188  *
3189  * For xnack off:
3190  * If range map to single GPU, the best prefetch location is prefetch_loc, which
3191  * can be CPU or GPU.
3192  *
3193  * If range is ACCESS or ACCESS_IN_PLACE by mGPUs, only if mGPU connection on
3194  * XGMI same hive, the best prefetch location is prefetch_loc GPU, othervise
3195  * the best prefetch location is always CPU, because GPU can not have coherent
3196  * mapping VRAM of other GPUs even with large-BAR PCIe connection.
3197  *
3198  * For xnack on:
3199  * If range is not ACCESS_IN_PLACE by mGPUs, the best prefetch location is
3200  * prefetch_loc, other GPU access will generate vm fault and trigger migration.
3201  *
3202  * If range is ACCESS_IN_PLACE by mGPUs, only if mGPU connection on XGMI same
3203  * hive, the best prefetch location is prefetch_loc GPU, otherwise the best
3204  * prefetch location is always CPU.
3205  *
3206  * Context: Process context
3207  *
3208  * Return:
3209  * 0 for CPU or GPU id
3210  */
3211 static uint32_t
3212 svm_range_best_prefetch_location(struct svm_range *prange)
3213 {
3214 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
3215 	uint32_t best_loc = prange->prefetch_loc;
3216 	struct kfd_process_device *pdd;
3217 	struct amdgpu_device *bo_adev;
3218 	struct kfd_process *p;
3219 	uint32_t gpuidx;
3220 
3221 	p = container_of(prange->svms, struct kfd_process, svms);
3222 
3223 	if (!best_loc || best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED)
3224 		goto out;
3225 
3226 	bo_adev = svm_range_get_adev_by_id(prange, best_loc);
3227 	if (!bo_adev) {
3228 		WARN_ONCE(1, "failed to get device by id 0x%x\n", best_loc);
3229 		best_loc = 0;
3230 		goto out;
3231 	}
3232 
3233 	if (p->xnack_enabled)
3234 		bitmap_copy(bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
3235 	else
3236 		bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
3237 			  MAX_GPU_INSTANCE);
3238 
3239 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
3240 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
3241 		if (!pdd) {
3242 			pr_debug("failed to get device by idx 0x%x\n", gpuidx);
3243 			continue;
3244 		}
3245 
3246 		if (pdd->dev->adev == bo_adev)
3247 			continue;
3248 
3249 		if (!amdgpu_xgmi_same_hive(pdd->dev->adev, bo_adev)) {
3250 			best_loc = 0;
3251 			break;
3252 		}
3253 	}
3254 
3255 out:
3256 	pr_debug("xnack %d svms 0x%p [0x%lx 0x%lx] best loc 0x%x\n",
3257 		 p->xnack_enabled, &p->svms, prange->start, prange->last,
3258 		 best_loc);
3259 
3260 	return best_loc;
3261 }
3262 
3263 /* svm_range_trigger_migration - start page migration if prefetch loc changed
3264  * @mm: current process mm_struct
3265  * @prange: svm range structure
3266  * @migrated: output, true if migration is triggered
3267  *
3268  * If range perfetch_loc is GPU, actual loc is cpu 0, then migrate the range
3269  * from ram to vram.
3270  * If range prefetch_loc is cpu 0, actual loc is GPU, then migrate the range
3271  * from vram to ram.
3272  *
3273  * If GPU vm fault retry is not enabled, migration interact with MMU notifier
3274  * and restore work:
3275  * 1. migrate_vma_setup invalidate pages, MMU notifier callback svm_range_evict
3276  *    stops all queues, schedule restore work
3277  * 2. svm_range_restore_work wait for migration is done by
3278  *    a. svm_range_validate_vram takes prange->migrate_mutex
3279  *    b. svm_range_validate_ram HMM get pages wait for CPU fault handle returns
3280  * 3. restore work update mappings of GPU, resume all queues.
3281  *
3282  * Context: Process context
3283  *
3284  * Return:
3285  * 0 - OK, otherwise - error code of migration
3286  */
3287 static int
3288 svm_range_trigger_migration(struct mm_struct *mm, struct svm_range *prange,
3289 			    bool *migrated)
3290 {
3291 	uint32_t best_loc;
3292 	int r = 0;
3293 
3294 	*migrated = false;
3295 	best_loc = svm_range_best_prefetch_location(prange);
3296 
3297 	if (best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3298 	    best_loc == prange->actual_loc)
3299 		return 0;
3300 
3301 	if (!best_loc) {
3302 		r = svm_migrate_vram_to_ram(prange, mm,
3303 					KFD_MIGRATE_TRIGGER_PREFETCH, NULL);
3304 		*migrated = !r;
3305 		return r;
3306 	}
3307 
3308 	r = svm_migrate_to_vram(prange, best_loc, mm, KFD_MIGRATE_TRIGGER_PREFETCH);
3309 	*migrated = !r;
3310 
3311 	return r;
3312 }
3313 
3314 int svm_range_schedule_evict_svm_bo(struct amdgpu_amdkfd_fence *fence)
3315 {
3316 	if (!fence)
3317 		return -EINVAL;
3318 
3319 	if (dma_fence_is_signaled(&fence->base))
3320 		return 0;
3321 
3322 	if (fence->svm_bo) {
3323 		WRITE_ONCE(fence->svm_bo->evicting, 1);
3324 		schedule_work(&fence->svm_bo->eviction_work);
3325 	}
3326 
3327 	return 0;
3328 }
3329 
3330 static void svm_range_evict_svm_bo_worker(struct work_struct *work)
3331 {
3332 	struct svm_range_bo *svm_bo;
3333 	struct mm_struct *mm;
3334 	int r = 0;
3335 
3336 	svm_bo = container_of(work, struct svm_range_bo, eviction_work);
3337 	if (!svm_bo_ref_unless_zero(svm_bo))
3338 		return; /* svm_bo was freed while eviction was pending */
3339 
3340 	if (mmget_not_zero(svm_bo->eviction_fence->mm)) {
3341 		mm = svm_bo->eviction_fence->mm;
3342 	} else {
3343 		svm_range_bo_unref(svm_bo);
3344 		return;
3345 	}
3346 
3347 	mmap_read_lock(mm);
3348 	spin_lock(&svm_bo->list_lock);
3349 	while (!list_empty(&svm_bo->range_list) && !r) {
3350 		struct svm_range *prange =
3351 				list_first_entry(&svm_bo->range_list,
3352 						struct svm_range, svm_bo_list);
3353 		int retries = 3;
3354 
3355 		list_del_init(&prange->svm_bo_list);
3356 		spin_unlock(&svm_bo->list_lock);
3357 
3358 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
3359 			 prange->start, prange->last);
3360 
3361 		mutex_lock(&prange->migrate_mutex);
3362 		do {
3363 			r = svm_migrate_vram_to_ram(prange, mm,
3364 					KFD_MIGRATE_TRIGGER_TTM_EVICTION, NULL);
3365 		} while (!r && prange->actual_loc && --retries);
3366 
3367 		if (!r && prange->actual_loc)
3368 			pr_info_once("Migration failed during eviction");
3369 
3370 		if (!prange->actual_loc) {
3371 			mutex_lock(&prange->lock);
3372 			prange->svm_bo = NULL;
3373 			mutex_unlock(&prange->lock);
3374 		}
3375 		mutex_unlock(&prange->migrate_mutex);
3376 
3377 		spin_lock(&svm_bo->list_lock);
3378 	}
3379 	spin_unlock(&svm_bo->list_lock);
3380 	mmap_read_unlock(mm);
3381 	mmput(mm);
3382 
3383 	dma_fence_signal(&svm_bo->eviction_fence->base);
3384 
3385 	/* This is the last reference to svm_bo, after svm_range_vram_node_free
3386 	 * has been called in svm_migrate_vram_to_ram
3387 	 */
3388 	WARN_ONCE(!r && kref_read(&svm_bo->kref) != 1, "This was not the last reference\n");
3389 	svm_range_bo_unref(svm_bo);
3390 }
3391 
3392 static int
3393 svm_range_set_attr(struct kfd_process *p, struct mm_struct *mm,
3394 		   uint64_t start, uint64_t size, uint32_t nattr,
3395 		   struct kfd_ioctl_svm_attribute *attrs)
3396 {
3397 	struct amdkfd_process_info *process_info = p->kgd_process_info;
3398 	struct list_head update_list;
3399 	struct list_head insert_list;
3400 	struct list_head remove_list;
3401 	struct svm_range_list *svms;
3402 	struct svm_range *prange;
3403 	struct svm_range *next;
3404 	bool update_mapping = false;
3405 	bool flush_tlb;
3406 	int r = 0;
3407 
3408 	pr_debug("pasid 0x%x svms 0x%p [0x%llx 0x%llx] pages 0x%llx\n",
3409 		 p->pasid, &p->svms, start, start + size - 1, size);
3410 
3411 	r = svm_range_check_attr(p, nattr, attrs);
3412 	if (r)
3413 		return r;
3414 
3415 	svms = &p->svms;
3416 
3417 	mutex_lock(&process_info->lock);
3418 
3419 	svm_range_list_lock_and_flush_work(svms, mm);
3420 
3421 	r = svm_range_is_valid(p, start, size);
3422 	if (r) {
3423 		pr_debug("invalid range r=%d\n", r);
3424 		mmap_write_unlock(mm);
3425 		goto out;
3426 	}
3427 
3428 	mutex_lock(&svms->lock);
3429 
3430 	/* Add new range and split existing ranges as needed */
3431 	r = svm_range_add(p, start, size, nattr, attrs, &update_list,
3432 			  &insert_list, &remove_list);
3433 	if (r) {
3434 		mutex_unlock(&svms->lock);
3435 		mmap_write_unlock(mm);
3436 		goto out;
3437 	}
3438 	/* Apply changes as a transaction */
3439 	list_for_each_entry_safe(prange, next, &insert_list, list) {
3440 		svm_range_add_to_svms(prange);
3441 		svm_range_add_notifier_locked(mm, prange);
3442 	}
3443 	list_for_each_entry(prange, &update_list, update_list) {
3444 		svm_range_apply_attrs(p, prange, nattr, attrs, &update_mapping);
3445 		/* TODO: unmap ranges from GPU that lost access */
3446 	}
3447 	list_for_each_entry_safe(prange, next, &remove_list, update_list) {
3448 		pr_debug("unlink old 0x%p prange 0x%p [0x%lx 0x%lx]\n",
3449 			 prange->svms, prange, prange->start,
3450 			 prange->last);
3451 		svm_range_unlink(prange);
3452 		svm_range_remove_notifier(prange);
3453 		svm_range_free(prange, false);
3454 	}
3455 
3456 	mmap_write_downgrade(mm);
3457 	/* Trigger migrations and revalidate and map to GPUs as needed. If
3458 	 * this fails we may be left with partially completed actions. There
3459 	 * is no clean way of rolling back to the previous state in such a
3460 	 * case because the rollback wouldn't be guaranteed to work either.
3461 	 */
3462 	list_for_each_entry(prange, &update_list, update_list) {
3463 		bool migrated;
3464 
3465 		mutex_lock(&prange->migrate_mutex);
3466 
3467 		r = svm_range_trigger_migration(mm, prange, &migrated);
3468 		if (r)
3469 			goto out_unlock_range;
3470 
3471 		if (migrated && (!p->xnack_enabled ||
3472 		    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) &&
3473 		    prange->mapped_to_gpu) {
3474 			pr_debug("restore_work will update mappings of GPUs\n");
3475 			mutex_unlock(&prange->migrate_mutex);
3476 			continue;
3477 		}
3478 
3479 		if (!migrated && !update_mapping) {
3480 			mutex_unlock(&prange->migrate_mutex);
3481 			continue;
3482 		}
3483 
3484 		flush_tlb = !migrated && update_mapping && prange->mapped_to_gpu;
3485 
3486 		r = svm_range_validate_and_map(mm, prange, MAX_GPU_INSTANCE,
3487 					       true, true, flush_tlb);
3488 		if (r)
3489 			pr_debug("failed %d to map svm range\n", r);
3490 
3491 out_unlock_range:
3492 		mutex_unlock(&prange->migrate_mutex);
3493 		if (r)
3494 			break;
3495 	}
3496 
3497 	svm_range_debug_dump(svms);
3498 
3499 	mutex_unlock(&svms->lock);
3500 	mmap_read_unlock(mm);
3501 out:
3502 	mutex_unlock(&process_info->lock);
3503 
3504 	pr_debug("pasid 0x%x svms 0x%p [0x%llx 0x%llx] done, r=%d\n", p->pasid,
3505 		 &p->svms, start, start + size - 1, r);
3506 
3507 	return r;
3508 }
3509 
3510 static int
3511 svm_range_get_attr(struct kfd_process *p, struct mm_struct *mm,
3512 		   uint64_t start, uint64_t size, uint32_t nattr,
3513 		   struct kfd_ioctl_svm_attribute *attrs)
3514 {
3515 	DECLARE_BITMAP(bitmap_access, MAX_GPU_INSTANCE);
3516 	DECLARE_BITMAP(bitmap_aip, MAX_GPU_INSTANCE);
3517 	bool get_preferred_loc = false;
3518 	bool get_prefetch_loc = false;
3519 	bool get_granularity = false;
3520 	bool get_accessible = false;
3521 	bool get_flags = false;
3522 	uint64_t last = start + size - 1UL;
3523 	uint8_t granularity = 0xff;
3524 	struct interval_tree_node *node;
3525 	struct svm_range_list *svms;
3526 	struct svm_range *prange;
3527 	uint32_t prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3528 	uint32_t location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3529 	uint32_t flags_and = 0xffffffff;
3530 	uint32_t flags_or = 0;
3531 	int gpuidx;
3532 	uint32_t i;
3533 	int r = 0;
3534 
3535 	pr_debug("svms 0x%p [0x%llx 0x%llx] nattr 0x%x\n", &p->svms, start,
3536 		 start + size - 1, nattr);
3537 
3538 	/* Flush pending deferred work to avoid racing with deferred actions from
3539 	 * previous memory map changes (e.g. munmap). Concurrent memory map changes
3540 	 * can still race with get_attr because we don't hold the mmap lock. But that
3541 	 * would be a race condition in the application anyway, and undefined
3542 	 * behaviour is acceptable in that case.
3543 	 */
3544 	flush_work(&p->svms.deferred_list_work);
3545 
3546 	mmap_read_lock(mm);
3547 	r = svm_range_is_valid(p, start, size);
3548 	mmap_read_unlock(mm);
3549 	if (r) {
3550 		pr_debug("invalid range r=%d\n", r);
3551 		return r;
3552 	}
3553 
3554 	for (i = 0; i < nattr; i++) {
3555 		switch (attrs[i].type) {
3556 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3557 			get_preferred_loc = true;
3558 			break;
3559 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3560 			get_prefetch_loc = true;
3561 			break;
3562 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3563 			get_accessible = true;
3564 			break;
3565 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3566 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3567 			get_flags = true;
3568 			break;
3569 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3570 			get_granularity = true;
3571 			break;
3572 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
3573 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
3574 			fallthrough;
3575 		default:
3576 			pr_debug("get invalid attr type 0x%x\n", attrs[i].type);
3577 			return -EINVAL;
3578 		}
3579 	}
3580 
3581 	svms = &p->svms;
3582 
3583 	mutex_lock(&svms->lock);
3584 
3585 	node = interval_tree_iter_first(&svms->objects, start, last);
3586 	if (!node) {
3587 		pr_debug("range attrs not found return default values\n");
3588 		svm_range_set_default_attributes(&location, &prefetch_loc,
3589 						 &granularity, &flags_and);
3590 		flags_or = flags_and;
3591 		if (p->xnack_enabled)
3592 			bitmap_copy(bitmap_access, svms->bitmap_supported,
3593 				    MAX_GPU_INSTANCE);
3594 		else
3595 			bitmap_zero(bitmap_access, MAX_GPU_INSTANCE);
3596 		bitmap_zero(bitmap_aip, MAX_GPU_INSTANCE);
3597 		goto fill_values;
3598 	}
3599 	bitmap_copy(bitmap_access, svms->bitmap_supported, MAX_GPU_INSTANCE);
3600 	bitmap_copy(bitmap_aip, svms->bitmap_supported, MAX_GPU_INSTANCE);
3601 
3602 	while (node) {
3603 		struct interval_tree_node *next;
3604 
3605 		prange = container_of(node, struct svm_range, it_node);
3606 		next = interval_tree_iter_next(node, start, last);
3607 
3608 		if (get_preferred_loc) {
3609 			if (prange->preferred_loc ==
3610 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3611 			    (location != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3612 			     location != prange->preferred_loc)) {
3613 				location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3614 				get_preferred_loc = false;
3615 			} else {
3616 				location = prange->preferred_loc;
3617 			}
3618 		}
3619 		if (get_prefetch_loc) {
3620 			if (prange->prefetch_loc ==
3621 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3622 			    (prefetch_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3623 			     prefetch_loc != prange->prefetch_loc)) {
3624 				prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3625 				get_prefetch_loc = false;
3626 			} else {
3627 				prefetch_loc = prange->prefetch_loc;
3628 			}
3629 		}
3630 		if (get_accessible) {
3631 			bitmap_and(bitmap_access, bitmap_access,
3632 				   prange->bitmap_access, MAX_GPU_INSTANCE);
3633 			bitmap_and(bitmap_aip, bitmap_aip,
3634 				   prange->bitmap_aip, MAX_GPU_INSTANCE);
3635 		}
3636 		if (get_flags) {
3637 			flags_and &= prange->flags;
3638 			flags_or |= prange->flags;
3639 		}
3640 
3641 		if (get_granularity && prange->granularity < granularity)
3642 			granularity = prange->granularity;
3643 
3644 		node = next;
3645 	}
3646 fill_values:
3647 	mutex_unlock(&svms->lock);
3648 
3649 	for (i = 0; i < nattr; i++) {
3650 		switch (attrs[i].type) {
3651 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3652 			attrs[i].value = location;
3653 			break;
3654 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3655 			attrs[i].value = prefetch_loc;
3656 			break;
3657 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3658 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
3659 							       attrs[i].value);
3660 			if (gpuidx < 0) {
3661 				pr_debug("invalid gpuid %x\n", attrs[i].value);
3662 				return -EINVAL;
3663 			}
3664 			if (test_bit(gpuidx, bitmap_access))
3665 				attrs[i].type = KFD_IOCTL_SVM_ATTR_ACCESS;
3666 			else if (test_bit(gpuidx, bitmap_aip))
3667 				attrs[i].type =
3668 					KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE;
3669 			else
3670 				attrs[i].type = KFD_IOCTL_SVM_ATTR_NO_ACCESS;
3671 			break;
3672 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3673 			attrs[i].value = flags_and;
3674 			break;
3675 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3676 			attrs[i].value = ~flags_or;
3677 			break;
3678 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3679 			attrs[i].value = (uint32_t)granularity;
3680 			break;
3681 		}
3682 	}
3683 
3684 	return 0;
3685 }
3686 
3687 int kfd_criu_resume_svm(struct kfd_process *p)
3688 {
3689 	struct kfd_ioctl_svm_attribute *set_attr_new, *set_attr = NULL;
3690 	int nattr_common = 4, nattr_accessibility = 1;
3691 	struct criu_svm_metadata *criu_svm_md = NULL;
3692 	struct svm_range_list *svms = &p->svms;
3693 	struct criu_svm_metadata *next = NULL;
3694 	uint32_t set_flags = 0xffffffff;
3695 	int i, j, num_attrs, ret = 0;
3696 	uint64_t set_attr_size;
3697 	struct mm_struct *mm;
3698 
3699 	if (list_empty(&svms->criu_svm_metadata_list)) {
3700 		pr_debug("No SVM data from CRIU restore stage 2\n");
3701 		return ret;
3702 	}
3703 
3704 	mm = get_task_mm(p->lead_thread);
3705 	if (!mm) {
3706 		pr_err("failed to get mm for the target process\n");
3707 		return -ESRCH;
3708 	}
3709 
3710 	num_attrs = nattr_common + (nattr_accessibility * p->n_pdds);
3711 
3712 	i = j = 0;
3713 	list_for_each_entry(criu_svm_md, &svms->criu_svm_metadata_list, list) {
3714 		pr_debug("criu_svm_md[%d]\n\tstart: 0x%llx size: 0x%llx (npages)\n",
3715 			 i, criu_svm_md->data.start_addr, criu_svm_md->data.size);
3716 
3717 		for (j = 0; j < num_attrs; j++) {
3718 			pr_debug("\ncriu_svm_md[%d]->attrs[%d].type : 0x%x\ncriu_svm_md[%d]->attrs[%d].value : 0x%x\n",
3719 				 i, j, criu_svm_md->data.attrs[j].type,
3720 				 i, j, criu_svm_md->data.attrs[j].value);
3721 			switch (criu_svm_md->data.attrs[j].type) {
3722 			/* During Checkpoint operation, the query for
3723 			 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC attribute might
3724 			 * return KFD_IOCTL_SVM_LOCATION_UNDEFINED if they were
3725 			 * not used by the range which was checkpointed. Care
3726 			 * must be taken to not restore with an invalid value
3727 			 * otherwise the gpuidx value will be invalid and
3728 			 * set_attr would eventually fail so just replace those
3729 			 * with another dummy attribute such as
3730 			 * KFD_IOCTL_SVM_ATTR_SET_FLAGS.
3731 			 */
3732 			case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3733 				if (criu_svm_md->data.attrs[j].value ==
3734 				    KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
3735 					criu_svm_md->data.attrs[j].type =
3736 						KFD_IOCTL_SVM_ATTR_SET_FLAGS;
3737 					criu_svm_md->data.attrs[j].value = 0;
3738 				}
3739 				break;
3740 			case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3741 				set_flags = criu_svm_md->data.attrs[j].value;
3742 				break;
3743 			default:
3744 				break;
3745 			}
3746 		}
3747 
3748 		/* CLR_FLAGS is not available via get_attr during checkpoint but
3749 		 * it needs to be inserted before restoring the ranges so
3750 		 * allocate extra space for it before calling set_attr
3751 		 */
3752 		set_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
3753 						(num_attrs + 1);
3754 		set_attr_new = krealloc(set_attr, set_attr_size,
3755 					    GFP_KERNEL);
3756 		if (!set_attr_new) {
3757 			ret = -ENOMEM;
3758 			goto exit;
3759 		}
3760 		set_attr = set_attr_new;
3761 
3762 		memcpy(set_attr, criu_svm_md->data.attrs, num_attrs *
3763 					sizeof(struct kfd_ioctl_svm_attribute));
3764 		set_attr[num_attrs].type = KFD_IOCTL_SVM_ATTR_CLR_FLAGS;
3765 		set_attr[num_attrs].value = ~set_flags;
3766 
3767 		ret = svm_range_set_attr(p, mm, criu_svm_md->data.start_addr,
3768 					 criu_svm_md->data.size, num_attrs + 1,
3769 					 set_attr);
3770 		if (ret) {
3771 			pr_err("CRIU: failed to set range attributes\n");
3772 			goto exit;
3773 		}
3774 
3775 		i++;
3776 	}
3777 exit:
3778 	kfree(set_attr);
3779 	list_for_each_entry_safe(criu_svm_md, next, &svms->criu_svm_metadata_list, list) {
3780 		pr_debug("freeing criu_svm_md[]\n\tstart: 0x%llx\n",
3781 						criu_svm_md->data.start_addr);
3782 		kfree(criu_svm_md);
3783 	}
3784 
3785 	mmput(mm);
3786 	return ret;
3787 
3788 }
3789 
3790 int kfd_criu_restore_svm(struct kfd_process *p,
3791 			 uint8_t __user *user_priv_ptr,
3792 			 uint64_t *priv_data_offset,
3793 			 uint64_t max_priv_data_size)
3794 {
3795 	uint64_t svm_priv_data_size, svm_object_md_size, svm_attrs_size;
3796 	int nattr_common = 4, nattr_accessibility = 1;
3797 	struct criu_svm_metadata *criu_svm_md = NULL;
3798 	struct svm_range_list *svms = &p->svms;
3799 	uint32_t num_devices;
3800 	int ret = 0;
3801 
3802 	num_devices = p->n_pdds;
3803 	/* Handle one SVM range object at a time, also the number of gpus are
3804 	 * assumed to be same on the restore node, checking must be done while
3805 	 * evaluating the topology earlier
3806 	 */
3807 
3808 	svm_attrs_size = sizeof(struct kfd_ioctl_svm_attribute) *
3809 		(nattr_common + nattr_accessibility * num_devices);
3810 	svm_object_md_size = sizeof(struct criu_svm_metadata) + svm_attrs_size;
3811 
3812 	svm_priv_data_size = sizeof(struct kfd_criu_svm_range_priv_data) +
3813 								svm_attrs_size;
3814 
3815 	criu_svm_md = kzalloc(svm_object_md_size, GFP_KERNEL);
3816 	if (!criu_svm_md) {
3817 		pr_err("failed to allocate memory to store svm metadata\n");
3818 		return -ENOMEM;
3819 	}
3820 	if (*priv_data_offset + svm_priv_data_size > max_priv_data_size) {
3821 		ret = -EINVAL;
3822 		goto exit;
3823 	}
3824 
3825 	ret = copy_from_user(&criu_svm_md->data, user_priv_ptr + *priv_data_offset,
3826 			     svm_priv_data_size);
3827 	if (ret) {
3828 		ret = -EFAULT;
3829 		goto exit;
3830 	}
3831 	*priv_data_offset += svm_priv_data_size;
3832 
3833 	list_add_tail(&criu_svm_md->list, &svms->criu_svm_metadata_list);
3834 
3835 	return 0;
3836 
3837 
3838 exit:
3839 	kfree(criu_svm_md);
3840 	return ret;
3841 }
3842 
3843 int svm_range_get_info(struct kfd_process *p, uint32_t *num_svm_ranges,
3844 		       uint64_t *svm_priv_data_size)
3845 {
3846 	uint64_t total_size, accessibility_size, common_attr_size;
3847 	int nattr_common = 4, nattr_accessibility = 1;
3848 	int num_devices = p->n_pdds;
3849 	struct svm_range_list *svms;
3850 	struct svm_range *prange;
3851 	uint32_t count = 0;
3852 
3853 	*svm_priv_data_size = 0;
3854 
3855 	svms = &p->svms;
3856 	if (!svms)
3857 		return -EINVAL;
3858 
3859 	mutex_lock(&svms->lock);
3860 	list_for_each_entry(prange, &svms->list, list) {
3861 		pr_debug("prange: 0x%p start: 0x%lx\t npages: 0x%llx\t end: 0x%llx\n",
3862 			 prange, prange->start, prange->npages,
3863 			 prange->start + prange->npages - 1);
3864 		count++;
3865 	}
3866 	mutex_unlock(&svms->lock);
3867 
3868 	*num_svm_ranges = count;
3869 	/* Only the accessbility attributes need to be queried for all the gpus
3870 	 * individually, remaining ones are spanned across the entire process
3871 	 * regardless of the various gpu nodes. Of the remaining attributes,
3872 	 * KFD_IOCTL_SVM_ATTR_CLR_FLAGS need not be saved.
3873 	 *
3874 	 * KFD_IOCTL_SVM_ATTR_PREFERRED_LOC
3875 	 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC
3876 	 * KFD_IOCTL_SVM_ATTR_SET_FLAGS
3877 	 * KFD_IOCTL_SVM_ATTR_GRANULARITY
3878 	 *
3879 	 * ** ACCESSBILITY ATTRIBUTES **
3880 	 * (Considered as one, type is altered during query, value is gpuid)
3881 	 * KFD_IOCTL_SVM_ATTR_ACCESS
3882 	 * KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE
3883 	 * KFD_IOCTL_SVM_ATTR_NO_ACCESS
3884 	 */
3885 	if (*num_svm_ranges > 0) {
3886 		common_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
3887 			nattr_common;
3888 		accessibility_size = sizeof(struct kfd_ioctl_svm_attribute) *
3889 			nattr_accessibility * num_devices;
3890 
3891 		total_size = sizeof(struct kfd_criu_svm_range_priv_data) +
3892 			common_attr_size + accessibility_size;
3893 
3894 		*svm_priv_data_size = *num_svm_ranges * total_size;
3895 	}
3896 
3897 	pr_debug("num_svm_ranges %u total_priv_size %llu\n", *num_svm_ranges,
3898 		 *svm_priv_data_size);
3899 	return 0;
3900 }
3901 
3902 int kfd_criu_checkpoint_svm(struct kfd_process *p,
3903 			    uint8_t __user *user_priv_data,
3904 			    uint64_t *priv_data_offset)
3905 {
3906 	struct kfd_criu_svm_range_priv_data *svm_priv = NULL;
3907 	struct kfd_ioctl_svm_attribute *query_attr = NULL;
3908 	uint64_t svm_priv_data_size, query_attr_size = 0;
3909 	int index, nattr_common = 4, ret = 0;
3910 	struct svm_range_list *svms;
3911 	int num_devices = p->n_pdds;
3912 	struct svm_range *prange;
3913 	struct mm_struct *mm;
3914 
3915 	svms = &p->svms;
3916 	if (!svms)
3917 		return -EINVAL;
3918 
3919 	mm = get_task_mm(p->lead_thread);
3920 	if (!mm) {
3921 		pr_err("failed to get mm for the target process\n");
3922 		return -ESRCH;
3923 	}
3924 
3925 	query_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
3926 				(nattr_common + num_devices);
3927 
3928 	query_attr = kzalloc(query_attr_size, GFP_KERNEL);
3929 	if (!query_attr) {
3930 		ret = -ENOMEM;
3931 		goto exit;
3932 	}
3933 
3934 	query_attr[0].type = KFD_IOCTL_SVM_ATTR_PREFERRED_LOC;
3935 	query_attr[1].type = KFD_IOCTL_SVM_ATTR_PREFETCH_LOC;
3936 	query_attr[2].type = KFD_IOCTL_SVM_ATTR_SET_FLAGS;
3937 	query_attr[3].type = KFD_IOCTL_SVM_ATTR_GRANULARITY;
3938 
3939 	for (index = 0; index < num_devices; index++) {
3940 		struct kfd_process_device *pdd = p->pdds[index];
3941 
3942 		query_attr[index + nattr_common].type =
3943 			KFD_IOCTL_SVM_ATTR_ACCESS;
3944 		query_attr[index + nattr_common].value = pdd->user_gpu_id;
3945 	}
3946 
3947 	svm_priv_data_size = sizeof(*svm_priv) + query_attr_size;
3948 
3949 	svm_priv = kzalloc(svm_priv_data_size, GFP_KERNEL);
3950 	if (!svm_priv) {
3951 		ret = -ENOMEM;
3952 		goto exit_query;
3953 	}
3954 
3955 	index = 0;
3956 	list_for_each_entry(prange, &svms->list, list) {
3957 
3958 		svm_priv->object_type = KFD_CRIU_OBJECT_TYPE_SVM_RANGE;
3959 		svm_priv->start_addr = prange->start;
3960 		svm_priv->size = prange->npages;
3961 		memcpy(&svm_priv->attrs, query_attr, query_attr_size);
3962 		pr_debug("CRIU: prange: 0x%p start: 0x%lx\t npages: 0x%llx end: 0x%llx\t size: 0x%llx\n",
3963 			 prange, prange->start, prange->npages,
3964 			 prange->start + prange->npages - 1,
3965 			 prange->npages * PAGE_SIZE);
3966 
3967 		ret = svm_range_get_attr(p, mm, svm_priv->start_addr,
3968 					 svm_priv->size,
3969 					 (nattr_common + num_devices),
3970 					 svm_priv->attrs);
3971 		if (ret) {
3972 			pr_err("CRIU: failed to obtain range attributes\n");
3973 			goto exit_priv;
3974 		}
3975 
3976 		if (copy_to_user(user_priv_data + *priv_data_offset, svm_priv,
3977 				 svm_priv_data_size)) {
3978 			pr_err("Failed to copy svm priv to user\n");
3979 			ret = -EFAULT;
3980 			goto exit_priv;
3981 		}
3982 
3983 		*priv_data_offset += svm_priv_data_size;
3984 
3985 	}
3986 
3987 
3988 exit_priv:
3989 	kfree(svm_priv);
3990 exit_query:
3991 	kfree(query_attr);
3992 exit:
3993 	mmput(mm);
3994 	return ret;
3995 }
3996 
3997 int
3998 svm_ioctl(struct kfd_process *p, enum kfd_ioctl_svm_op op, uint64_t start,
3999 	  uint64_t size, uint32_t nattrs, struct kfd_ioctl_svm_attribute *attrs)
4000 {
4001 	struct mm_struct *mm = current->mm;
4002 	int r;
4003 
4004 	start >>= PAGE_SHIFT;
4005 	size >>= PAGE_SHIFT;
4006 
4007 	switch (op) {
4008 	case KFD_IOCTL_SVM_OP_SET_ATTR:
4009 		r = svm_range_set_attr(p, mm, start, size, nattrs, attrs);
4010 		break;
4011 	case KFD_IOCTL_SVM_OP_GET_ATTR:
4012 		r = svm_range_get_attr(p, mm, start, size, nattrs, attrs);
4013 		break;
4014 	default:
4015 		r = EINVAL;
4016 		break;
4017 	}
4018 
4019 	return r;
4020 }
4021