xref: /openbmc/linux/drivers/gpu/drm/amd/amdkfd/kfd_svm.c (revision 90cbee20)
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 = prange->svm_bo->node->adev;
174 
175 			addr[i] = (hmm_pfns[i] << PAGE_SHIFT) +
176 				   bo_adev->vm_manager.vram_base_offset -
177 				   bo_adev->kfd.dev->pgmap.range.start;
178 			addr[i] |= SVM_RANGE_VRAM_DOMAIN;
179 			pr_debug_ratelimited("vram address: 0x%llx\n", addr[i]);
180 			continue;
181 		}
182 		addr[i] = dma_map_page(dev, page, 0, PAGE_SIZE, dir);
183 		r = dma_mapping_error(dev, addr[i]);
184 		if (r) {
185 			dev_err(dev, "failed %d dma_map_page\n", r);
186 			return r;
187 		}
188 		pr_debug_ratelimited("dma mapping 0x%llx for page addr 0x%lx\n",
189 				     addr[i] >> PAGE_SHIFT, page_to_pfn(page));
190 	}
191 	return 0;
192 }
193 
194 static int
195 svm_range_dma_map(struct svm_range *prange, unsigned long *bitmap,
196 		  unsigned long offset, unsigned long npages,
197 		  unsigned long *hmm_pfns)
198 {
199 	struct kfd_process *p;
200 	uint32_t gpuidx;
201 	int r;
202 
203 	p = container_of(prange->svms, struct kfd_process, svms);
204 
205 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
206 		struct kfd_process_device *pdd;
207 
208 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
209 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
210 		if (!pdd) {
211 			pr_debug("failed to find device idx %d\n", gpuidx);
212 			return -EINVAL;
213 		}
214 
215 		r = svm_range_dma_map_dev(pdd->dev->adev, prange, offset, npages,
216 					  hmm_pfns, gpuidx);
217 		if (r)
218 			break;
219 	}
220 
221 	return r;
222 }
223 
224 void svm_range_dma_unmap(struct device *dev, dma_addr_t *dma_addr,
225 			 unsigned long offset, unsigned long npages)
226 {
227 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
228 	int i;
229 
230 	if (!dma_addr)
231 		return;
232 
233 	for (i = offset; i < offset + npages; i++) {
234 		if (!svm_is_valid_dma_mapping_addr(dev, dma_addr[i]))
235 			continue;
236 		pr_debug_ratelimited("unmap 0x%llx\n", dma_addr[i] >> PAGE_SHIFT);
237 		dma_unmap_page(dev, dma_addr[i], PAGE_SIZE, dir);
238 		dma_addr[i] = 0;
239 	}
240 }
241 
242 void svm_range_free_dma_mappings(struct svm_range *prange)
243 {
244 	struct kfd_process_device *pdd;
245 	dma_addr_t *dma_addr;
246 	struct device *dev;
247 	struct kfd_process *p;
248 	uint32_t gpuidx;
249 
250 	p = container_of(prange->svms, struct kfd_process, svms);
251 
252 	for (gpuidx = 0; gpuidx < MAX_GPU_INSTANCE; gpuidx++) {
253 		dma_addr = prange->dma_addr[gpuidx];
254 		if (!dma_addr)
255 			continue;
256 
257 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
258 		if (!pdd) {
259 			pr_debug("failed to find device idx %d\n", gpuidx);
260 			continue;
261 		}
262 		dev = &pdd->dev->adev->pdev->dev;
263 		svm_range_dma_unmap(dev, dma_addr, 0, prange->npages);
264 		kvfree(dma_addr);
265 		prange->dma_addr[gpuidx] = NULL;
266 	}
267 }
268 
269 static void svm_range_free(struct svm_range *prange, bool update_mem_usage)
270 {
271 	uint64_t size = (prange->last - prange->start + 1) << PAGE_SHIFT;
272 	struct kfd_process *p = container_of(prange->svms, struct kfd_process, svms);
273 
274 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms, prange,
275 		 prange->start, prange->last);
276 
277 	svm_range_vram_node_free(prange);
278 	svm_range_free_dma_mappings(prange);
279 
280 	if (update_mem_usage && !p->xnack_enabled) {
281 		pr_debug("unreserve prange 0x%p size: 0x%llx\n", prange, size);
282 		amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
283 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR);
284 	}
285 	mutex_destroy(&prange->lock);
286 	mutex_destroy(&prange->migrate_mutex);
287 	kfree(prange);
288 }
289 
290 static void
291 svm_range_set_default_attributes(int32_t *location, int32_t *prefetch_loc,
292 				 uint8_t *granularity, uint32_t *flags)
293 {
294 	*location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
295 	*prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
296 	*granularity = 9;
297 	*flags =
298 		KFD_IOCTL_SVM_FLAG_HOST_ACCESS | KFD_IOCTL_SVM_FLAG_COHERENT;
299 }
300 
301 static struct
302 svm_range *svm_range_new(struct svm_range_list *svms, uint64_t start,
303 			 uint64_t last, bool update_mem_usage)
304 {
305 	uint64_t size = last - start + 1;
306 	struct svm_range *prange;
307 	struct kfd_process *p;
308 
309 	prange = kzalloc(sizeof(*prange), GFP_KERNEL);
310 	if (!prange)
311 		return NULL;
312 
313 	p = container_of(svms, struct kfd_process, svms);
314 	if (!p->xnack_enabled && update_mem_usage &&
315 	    amdgpu_amdkfd_reserve_mem_limit(NULL, size << PAGE_SHIFT,
316 					    KFD_IOC_ALLOC_MEM_FLAGS_USERPTR)) {
317 		pr_info("SVM mapping failed, exceeds resident system memory limit\n");
318 		kfree(prange);
319 		return NULL;
320 	}
321 	prange->npages = size;
322 	prange->svms = svms;
323 	prange->start = start;
324 	prange->last = last;
325 	INIT_LIST_HEAD(&prange->list);
326 	INIT_LIST_HEAD(&prange->update_list);
327 	INIT_LIST_HEAD(&prange->svm_bo_list);
328 	INIT_LIST_HEAD(&prange->deferred_list);
329 	INIT_LIST_HEAD(&prange->child_list);
330 	atomic_set(&prange->invalid, 0);
331 	prange->validate_timestamp = 0;
332 	mutex_init(&prange->migrate_mutex);
333 	mutex_init(&prange->lock);
334 
335 	if (p->xnack_enabled)
336 		bitmap_copy(prange->bitmap_access, svms->bitmap_supported,
337 			    MAX_GPU_INSTANCE);
338 
339 	svm_range_set_default_attributes(&prange->preferred_loc,
340 					 &prange->prefetch_loc,
341 					 &prange->granularity, &prange->flags);
342 
343 	pr_debug("svms 0x%p [0x%llx 0x%llx]\n", svms, start, last);
344 
345 	return prange;
346 }
347 
348 static bool svm_bo_ref_unless_zero(struct svm_range_bo *svm_bo)
349 {
350 	if (!svm_bo || !kref_get_unless_zero(&svm_bo->kref))
351 		return false;
352 
353 	return true;
354 }
355 
356 static void svm_range_bo_release(struct kref *kref)
357 {
358 	struct svm_range_bo *svm_bo;
359 
360 	svm_bo = container_of(kref, struct svm_range_bo, kref);
361 	pr_debug("svm_bo 0x%p\n", svm_bo);
362 
363 	spin_lock(&svm_bo->list_lock);
364 	while (!list_empty(&svm_bo->range_list)) {
365 		struct svm_range *prange =
366 				list_first_entry(&svm_bo->range_list,
367 						struct svm_range, svm_bo_list);
368 		/* list_del_init tells a concurrent svm_range_vram_node_new when
369 		 * it's safe to reuse the svm_bo pointer and svm_bo_list head.
370 		 */
371 		list_del_init(&prange->svm_bo_list);
372 		spin_unlock(&svm_bo->list_lock);
373 
374 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
375 			 prange->start, prange->last);
376 		mutex_lock(&prange->lock);
377 		prange->svm_bo = NULL;
378 		mutex_unlock(&prange->lock);
379 
380 		spin_lock(&svm_bo->list_lock);
381 	}
382 	spin_unlock(&svm_bo->list_lock);
383 	if (!dma_fence_is_signaled(&svm_bo->eviction_fence->base)) {
384 		/* We're not in the eviction worker.
385 		 * Signal the fence and synchronize with any
386 		 * pending eviction work.
387 		 */
388 		dma_fence_signal(&svm_bo->eviction_fence->base);
389 		cancel_work_sync(&svm_bo->eviction_work);
390 	}
391 	dma_fence_put(&svm_bo->eviction_fence->base);
392 	amdgpu_bo_unref(&svm_bo->bo);
393 	kfree(svm_bo);
394 }
395 
396 static void svm_range_bo_wq_release(struct work_struct *work)
397 {
398 	struct svm_range_bo *svm_bo;
399 
400 	svm_bo = container_of(work, struct svm_range_bo, release_work);
401 	svm_range_bo_release(&svm_bo->kref);
402 }
403 
404 static void svm_range_bo_release_async(struct kref *kref)
405 {
406 	struct svm_range_bo *svm_bo;
407 
408 	svm_bo = container_of(kref, struct svm_range_bo, kref);
409 	pr_debug("svm_bo 0x%p\n", svm_bo);
410 	INIT_WORK(&svm_bo->release_work, svm_range_bo_wq_release);
411 	schedule_work(&svm_bo->release_work);
412 }
413 
414 void svm_range_bo_unref_async(struct svm_range_bo *svm_bo)
415 {
416 	kref_put(&svm_bo->kref, svm_range_bo_release_async);
417 }
418 
419 static void svm_range_bo_unref(struct svm_range_bo *svm_bo)
420 {
421 	if (svm_bo)
422 		kref_put(&svm_bo->kref, svm_range_bo_release);
423 }
424 
425 static bool
426 svm_range_validate_svm_bo(struct kfd_node *node, struct svm_range *prange)
427 {
428 	mutex_lock(&prange->lock);
429 	if (!prange->svm_bo) {
430 		mutex_unlock(&prange->lock);
431 		return false;
432 	}
433 	if (prange->ttm_res) {
434 		/* We still have a reference, all is well */
435 		mutex_unlock(&prange->lock);
436 		return true;
437 	}
438 	if (svm_bo_ref_unless_zero(prange->svm_bo)) {
439 		/*
440 		 * Migrate from GPU to GPU, remove range from source svm_bo->node
441 		 * range list, and return false to allocate svm_bo from destination
442 		 * node.
443 		 */
444 		if (prange->svm_bo->node != node) {
445 			mutex_unlock(&prange->lock);
446 
447 			spin_lock(&prange->svm_bo->list_lock);
448 			list_del_init(&prange->svm_bo_list);
449 			spin_unlock(&prange->svm_bo->list_lock);
450 
451 			svm_range_bo_unref(prange->svm_bo);
452 			return false;
453 		}
454 		if (READ_ONCE(prange->svm_bo->evicting)) {
455 			struct dma_fence *f;
456 			struct svm_range_bo *svm_bo;
457 			/* The BO is getting evicted,
458 			 * we need to get a new one
459 			 */
460 			mutex_unlock(&prange->lock);
461 			svm_bo = prange->svm_bo;
462 			f = dma_fence_get(&svm_bo->eviction_fence->base);
463 			svm_range_bo_unref(prange->svm_bo);
464 			/* wait for the fence to avoid long spin-loop
465 			 * at list_empty_careful
466 			 */
467 			dma_fence_wait(f, false);
468 			dma_fence_put(f);
469 		} else {
470 			/* The BO was still around and we got
471 			 * a new reference to it
472 			 */
473 			mutex_unlock(&prange->lock);
474 			pr_debug("reuse old bo svms 0x%p [0x%lx 0x%lx]\n",
475 				 prange->svms, prange->start, prange->last);
476 
477 			prange->ttm_res = prange->svm_bo->bo->tbo.resource;
478 			return true;
479 		}
480 
481 	} else {
482 		mutex_unlock(&prange->lock);
483 	}
484 
485 	/* We need a new svm_bo. Spin-loop to wait for concurrent
486 	 * svm_range_bo_release to finish removing this range from
487 	 * its range list. After this, it is safe to reuse the
488 	 * svm_bo pointer and svm_bo_list head.
489 	 */
490 	while (!list_empty_careful(&prange->svm_bo_list))
491 		;
492 
493 	return false;
494 }
495 
496 static struct svm_range_bo *svm_range_bo_new(void)
497 {
498 	struct svm_range_bo *svm_bo;
499 
500 	svm_bo = kzalloc(sizeof(*svm_bo), GFP_KERNEL);
501 	if (!svm_bo)
502 		return NULL;
503 
504 	kref_init(&svm_bo->kref);
505 	INIT_LIST_HEAD(&svm_bo->range_list);
506 	spin_lock_init(&svm_bo->list_lock);
507 
508 	return svm_bo;
509 }
510 
511 int
512 svm_range_vram_node_new(struct kfd_node *node, struct svm_range *prange,
513 			bool clear)
514 {
515 	struct amdgpu_bo_param bp;
516 	struct svm_range_bo *svm_bo;
517 	struct amdgpu_bo_user *ubo;
518 	struct amdgpu_bo *bo;
519 	struct kfd_process *p;
520 	struct mm_struct *mm;
521 	int r;
522 
523 	p = container_of(prange->svms, struct kfd_process, svms);
524 	pr_debug("pasid: %x svms 0x%p [0x%lx 0x%lx]\n", p->pasid, prange->svms,
525 		 prange->start, prange->last);
526 
527 	if (svm_range_validate_svm_bo(node, prange))
528 		return 0;
529 
530 	svm_bo = svm_range_bo_new();
531 	if (!svm_bo) {
532 		pr_debug("failed to alloc svm bo\n");
533 		return -ENOMEM;
534 	}
535 	mm = get_task_mm(p->lead_thread);
536 	if (!mm) {
537 		pr_debug("failed to get mm\n");
538 		kfree(svm_bo);
539 		return -ESRCH;
540 	}
541 	svm_bo->node = node;
542 	svm_bo->eviction_fence =
543 		amdgpu_amdkfd_fence_create(dma_fence_context_alloc(1),
544 					   mm,
545 					   svm_bo);
546 	mmput(mm);
547 	INIT_WORK(&svm_bo->eviction_work, svm_range_evict_svm_bo_worker);
548 	svm_bo->evicting = 0;
549 	memset(&bp, 0, sizeof(bp));
550 	bp.size = prange->npages * PAGE_SIZE;
551 	bp.byte_align = PAGE_SIZE;
552 	bp.domain = AMDGPU_GEM_DOMAIN_VRAM;
553 	bp.flags = AMDGPU_GEM_CREATE_NO_CPU_ACCESS;
554 	bp.flags |= clear ? AMDGPU_GEM_CREATE_VRAM_CLEARED : 0;
555 	bp.flags |= AMDGPU_GEM_CREATE_DISCARDABLE;
556 	bp.type = ttm_bo_type_device;
557 	bp.resv = NULL;
558 
559 	/* TODO: Allocate memory from the right memory partition. We can sort
560 	 * out the details later, once basic memory partitioning is working
561 	 */
562 	r = amdgpu_bo_create_user(node->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 kfd_node *
621 svm_range_get_node_by_id(struct svm_range *prange, uint32_t gpu_id)
622 {
623 	struct kfd_process *p;
624 	struct kfd_process_device *pdd;
625 
626 	p = container_of(prange->svms, struct kfd_process, svms);
627 	pdd = kfd_process_device_data_by_id(p, gpu_id);
628 	if (!pdd) {
629 		pr_debug("failed to get kfd process device by id 0x%x\n", gpu_id);
630 		return NULL;
631 	}
632 
633 	return pdd->dev;
634 }
635 
636 struct kfd_process_device *
637 svm_range_get_pdd_by_node(struct svm_range *prange, struct kfd_node *node)
638 {
639 	struct kfd_process *p;
640 
641 	p = container_of(prange->svms, struct kfd_process, svms);
642 
643 	return kfd_get_process_device_data(node, p);
644 }
645 
646 static int svm_range_bo_validate(void *param, struct amdgpu_bo *bo)
647 {
648 	struct ttm_operation_ctx ctx = { false, false };
649 
650 	amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_VRAM);
651 
652 	return ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
653 }
654 
655 static int
656 svm_range_check_attr(struct kfd_process *p,
657 		     uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
658 {
659 	uint32_t i;
660 
661 	for (i = 0; i < nattr; i++) {
662 		uint32_t val = attrs[i].value;
663 		int gpuidx = MAX_GPU_INSTANCE;
664 
665 		switch (attrs[i].type) {
666 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
667 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM &&
668 			    val != KFD_IOCTL_SVM_LOCATION_UNDEFINED)
669 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
670 			break;
671 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
672 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM)
673 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
674 			break;
675 		case KFD_IOCTL_SVM_ATTR_ACCESS:
676 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
677 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
678 			gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
679 			break;
680 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
681 			break;
682 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
683 			break;
684 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
685 			break;
686 		default:
687 			pr_debug("unknown attr type 0x%x\n", attrs[i].type);
688 			return -EINVAL;
689 		}
690 
691 		if (gpuidx < 0) {
692 			pr_debug("no GPU 0x%x found\n", val);
693 			return -EINVAL;
694 		} else if (gpuidx < MAX_GPU_INSTANCE &&
695 			   !test_bit(gpuidx, p->svms.bitmap_supported)) {
696 			pr_debug("GPU 0x%x not supported\n", val);
697 			return -EINVAL;
698 		}
699 	}
700 
701 	return 0;
702 }
703 
704 static void
705 svm_range_apply_attrs(struct kfd_process *p, struct svm_range *prange,
706 		      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
707 		      bool *update_mapping)
708 {
709 	uint32_t i;
710 	int gpuidx;
711 
712 	for (i = 0; i < nattr; i++) {
713 		switch (attrs[i].type) {
714 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
715 			prange->preferred_loc = attrs[i].value;
716 			break;
717 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
718 			prange->prefetch_loc = attrs[i].value;
719 			break;
720 		case KFD_IOCTL_SVM_ATTR_ACCESS:
721 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
722 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
723 			if (!p->xnack_enabled)
724 				*update_mapping = true;
725 
726 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
727 							       attrs[i].value);
728 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
729 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
730 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
731 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
732 				bitmap_set(prange->bitmap_access, gpuidx, 1);
733 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
734 			} else {
735 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
736 				bitmap_set(prange->bitmap_aip, gpuidx, 1);
737 			}
738 			break;
739 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
740 			*update_mapping = true;
741 			prange->flags |= attrs[i].value;
742 			break;
743 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
744 			*update_mapping = true;
745 			prange->flags &= ~attrs[i].value;
746 			break;
747 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
748 			prange->granularity = attrs[i].value;
749 			break;
750 		default:
751 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
752 		}
753 	}
754 }
755 
756 static bool
757 svm_range_is_same_attrs(struct kfd_process *p, struct svm_range *prange,
758 			uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
759 {
760 	uint32_t i;
761 	int gpuidx;
762 
763 	for (i = 0; i < nattr; i++) {
764 		switch (attrs[i].type) {
765 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
766 			if (prange->preferred_loc != attrs[i].value)
767 				return false;
768 			break;
769 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
770 			/* Prefetch should always trigger a migration even
771 			 * if the value of the attribute didn't change.
772 			 */
773 			return false;
774 		case KFD_IOCTL_SVM_ATTR_ACCESS:
775 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
776 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
777 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
778 							       attrs[i].value);
779 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
780 				if (test_bit(gpuidx, prange->bitmap_access) ||
781 				    test_bit(gpuidx, prange->bitmap_aip))
782 					return false;
783 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
784 				if (!test_bit(gpuidx, prange->bitmap_access))
785 					return false;
786 			} else {
787 				if (!test_bit(gpuidx, prange->bitmap_aip))
788 					return false;
789 			}
790 			break;
791 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
792 			if ((prange->flags & attrs[i].value) != attrs[i].value)
793 				return false;
794 			break;
795 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
796 			if ((prange->flags & attrs[i].value) != 0)
797 				return false;
798 			break;
799 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
800 			if (prange->granularity != attrs[i].value)
801 				return false;
802 			break;
803 		default:
804 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
805 		}
806 	}
807 
808 	return true;
809 }
810 
811 /**
812  * svm_range_debug_dump - print all range information from svms
813  * @svms: svm range list header
814  *
815  * debug output svm range start, end, prefetch location from svms
816  * interval tree and link list
817  *
818  * Context: The caller must hold svms->lock
819  */
820 static void svm_range_debug_dump(struct svm_range_list *svms)
821 {
822 	struct interval_tree_node *node;
823 	struct svm_range *prange;
824 
825 	pr_debug("dump svms 0x%p list\n", svms);
826 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
827 
828 	list_for_each_entry(prange, &svms->list, list) {
829 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
830 			 prange, prange->start, prange->npages,
831 			 prange->start + prange->npages - 1,
832 			 prange->actual_loc);
833 	}
834 
835 	pr_debug("dump svms 0x%p interval tree\n", svms);
836 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
837 	node = interval_tree_iter_first(&svms->objects, 0, ~0ULL);
838 	while (node) {
839 		prange = container_of(node, struct svm_range, it_node);
840 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
841 			 prange, prange->start, prange->npages,
842 			 prange->start + prange->npages - 1,
843 			 prange->actual_loc);
844 		node = interval_tree_iter_next(node, 0, ~0ULL);
845 	}
846 }
847 
848 static int
849 svm_range_split_array(void *ppnew, void *ppold, size_t size,
850 		      uint64_t old_start, uint64_t old_n,
851 		      uint64_t new_start, uint64_t new_n)
852 {
853 	unsigned char *new, *old, *pold;
854 	uint64_t d;
855 
856 	if (!ppold)
857 		return 0;
858 	pold = *(unsigned char **)ppold;
859 	if (!pold)
860 		return 0;
861 
862 	new = kvmalloc_array(new_n, size, GFP_KERNEL);
863 	if (!new)
864 		return -ENOMEM;
865 
866 	d = (new_start - old_start) * size;
867 	memcpy(new, pold + d, new_n * size);
868 
869 	old = kvmalloc_array(old_n, size, GFP_KERNEL);
870 	if (!old) {
871 		kvfree(new);
872 		return -ENOMEM;
873 	}
874 
875 	d = (new_start == old_start) ? new_n * size : 0;
876 	memcpy(old, pold + d, old_n * size);
877 
878 	kvfree(pold);
879 	*(void **)ppold = old;
880 	*(void **)ppnew = new;
881 
882 	return 0;
883 }
884 
885 static int
886 svm_range_split_pages(struct svm_range *new, struct svm_range *old,
887 		      uint64_t start, uint64_t last)
888 {
889 	uint64_t npages = last - start + 1;
890 	int i, r;
891 
892 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
893 		r = svm_range_split_array(&new->dma_addr[i], &old->dma_addr[i],
894 					  sizeof(*old->dma_addr[i]), old->start,
895 					  npages, new->start, new->npages);
896 		if (r)
897 			return r;
898 	}
899 
900 	return 0;
901 }
902 
903 static int
904 svm_range_split_nodes(struct svm_range *new, struct svm_range *old,
905 		      uint64_t start, uint64_t last)
906 {
907 	uint64_t npages = last - start + 1;
908 
909 	pr_debug("svms 0x%p new prange 0x%p start 0x%lx [0x%llx 0x%llx]\n",
910 		 new->svms, new, new->start, start, last);
911 
912 	if (new->start == old->start) {
913 		new->offset = old->offset;
914 		old->offset += new->npages;
915 	} else {
916 		new->offset = old->offset + npages;
917 	}
918 
919 	new->svm_bo = svm_range_bo_ref(old->svm_bo);
920 	new->ttm_res = old->ttm_res;
921 
922 	spin_lock(&new->svm_bo->list_lock);
923 	list_add(&new->svm_bo_list, &new->svm_bo->range_list);
924 	spin_unlock(&new->svm_bo->list_lock);
925 
926 	return 0;
927 }
928 
929 /**
930  * svm_range_split_adjust - split range and adjust
931  *
932  * @new: new range
933  * @old: the old range
934  * @start: the old range adjust to start address in pages
935  * @last: the old range adjust to last address in pages
936  *
937  * Copy system memory dma_addr or vram ttm_res in old range to new
938  * range from new_start up to size new->npages, the remaining old range is from
939  * start to last
940  *
941  * Return:
942  * 0 - OK, -ENOMEM - out of memory
943  */
944 static int
945 svm_range_split_adjust(struct svm_range *new, struct svm_range *old,
946 		      uint64_t start, uint64_t last)
947 {
948 	int r;
949 
950 	pr_debug("svms 0x%p new 0x%lx old [0x%lx 0x%lx] => [0x%llx 0x%llx]\n",
951 		 new->svms, new->start, old->start, old->last, start, last);
952 
953 	if (new->start < old->start ||
954 	    new->last > old->last) {
955 		WARN_ONCE(1, "invalid new range start or last\n");
956 		return -EINVAL;
957 	}
958 
959 	r = svm_range_split_pages(new, old, start, last);
960 	if (r)
961 		return r;
962 
963 	if (old->actual_loc && old->ttm_res) {
964 		r = svm_range_split_nodes(new, old, start, last);
965 		if (r)
966 			return r;
967 	}
968 
969 	old->npages = last - start + 1;
970 	old->start = start;
971 	old->last = last;
972 	new->flags = old->flags;
973 	new->preferred_loc = old->preferred_loc;
974 	new->prefetch_loc = old->prefetch_loc;
975 	new->actual_loc = old->actual_loc;
976 	new->granularity = old->granularity;
977 	new->mapped_to_gpu = old->mapped_to_gpu;
978 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
979 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
980 
981 	return 0;
982 }
983 
984 /**
985  * svm_range_split - split a range in 2 ranges
986  *
987  * @prange: the svm range to split
988  * @start: the remaining range start address in pages
989  * @last: the remaining range last address in pages
990  * @new: the result new range generated
991  *
992  * Two cases only:
993  * case 1: if start == prange->start
994  *         prange ==> prange[start, last]
995  *         new range [last + 1, prange->last]
996  *
997  * case 2: if last == prange->last
998  *         prange ==> prange[start, last]
999  *         new range [prange->start, start - 1]
1000  *
1001  * Return:
1002  * 0 - OK, -ENOMEM - out of memory, -EINVAL - invalid start, last
1003  */
1004 static int
1005 svm_range_split(struct svm_range *prange, uint64_t start, uint64_t last,
1006 		struct svm_range **new)
1007 {
1008 	uint64_t old_start = prange->start;
1009 	uint64_t old_last = prange->last;
1010 	struct svm_range_list *svms;
1011 	int r = 0;
1012 
1013 	pr_debug("svms 0x%p [0x%llx 0x%llx] to [0x%llx 0x%llx]\n", prange->svms,
1014 		 old_start, old_last, start, last);
1015 
1016 	if (old_start != start && old_last != last)
1017 		return -EINVAL;
1018 	if (start < old_start || last > old_last)
1019 		return -EINVAL;
1020 
1021 	svms = prange->svms;
1022 	if (old_start == start)
1023 		*new = svm_range_new(svms, last + 1, old_last, false);
1024 	else
1025 		*new = svm_range_new(svms, old_start, start - 1, false);
1026 	if (!*new)
1027 		return -ENOMEM;
1028 
1029 	r = svm_range_split_adjust(*new, prange, start, last);
1030 	if (r) {
1031 		pr_debug("failed %d split [0x%llx 0x%llx] to [0x%llx 0x%llx]\n",
1032 			 r, old_start, old_last, start, last);
1033 		svm_range_free(*new, false);
1034 		*new = NULL;
1035 	}
1036 
1037 	return r;
1038 }
1039 
1040 static int
1041 svm_range_split_tail(struct svm_range *prange,
1042 		     uint64_t new_last, struct list_head *insert_list)
1043 {
1044 	struct svm_range *tail;
1045 	int r = svm_range_split(prange, prange->start, new_last, &tail);
1046 
1047 	if (!r)
1048 		list_add(&tail->list, insert_list);
1049 	return r;
1050 }
1051 
1052 static int
1053 svm_range_split_head(struct svm_range *prange,
1054 		     uint64_t new_start, struct list_head *insert_list)
1055 {
1056 	struct svm_range *head;
1057 	int r = svm_range_split(prange, new_start, prange->last, &head);
1058 
1059 	if (!r)
1060 		list_add(&head->list, insert_list);
1061 	return r;
1062 }
1063 
1064 static void
1065 svm_range_add_child(struct svm_range *prange, struct mm_struct *mm,
1066 		    struct svm_range *pchild, enum svm_work_list_ops op)
1067 {
1068 	pr_debug("add child 0x%p [0x%lx 0x%lx] to prange 0x%p child list %d\n",
1069 		 pchild, pchild->start, pchild->last, prange, op);
1070 
1071 	pchild->work_item.mm = mm;
1072 	pchild->work_item.op = op;
1073 	list_add_tail(&pchild->child_list, &prange->child_list);
1074 }
1075 
1076 /**
1077  * svm_range_split_by_granularity - collect ranges within granularity boundary
1078  *
1079  * @p: the process with svms list
1080  * @mm: mm structure
1081  * @addr: the vm fault address in pages, to split the prange
1082  * @parent: parent range if prange is from child list
1083  * @prange: prange to split
1084  *
1085  * Trims @prange to be a single aligned block of prange->granularity if
1086  * possible. The head and tail are added to the child_list in @parent.
1087  *
1088  * Context: caller must hold mmap_read_lock and prange->lock
1089  *
1090  * Return:
1091  * 0 - OK, otherwise error code
1092  */
1093 int
1094 svm_range_split_by_granularity(struct kfd_process *p, struct mm_struct *mm,
1095 			       unsigned long addr, struct svm_range *parent,
1096 			       struct svm_range *prange)
1097 {
1098 	struct svm_range *head, *tail;
1099 	unsigned long start, last, size;
1100 	int r;
1101 
1102 	/* Align splited range start and size to granularity size, then a single
1103 	 * PTE will be used for whole range, this reduces the number of PTE
1104 	 * updated and the L1 TLB space used for translation.
1105 	 */
1106 	size = 1UL << prange->granularity;
1107 	start = ALIGN_DOWN(addr, size);
1108 	last = ALIGN(addr + 1, size) - 1;
1109 
1110 	pr_debug("svms 0x%p split [0x%lx 0x%lx] to [0x%lx 0x%lx] size 0x%lx\n",
1111 		 prange->svms, prange->start, prange->last, start, last, size);
1112 
1113 	if (start > prange->start) {
1114 		r = svm_range_split(prange, start, prange->last, &head);
1115 		if (r)
1116 			return r;
1117 		svm_range_add_child(parent, mm, head, SVM_OP_ADD_RANGE);
1118 	}
1119 
1120 	if (last < prange->last) {
1121 		r = svm_range_split(prange, prange->start, last, &tail);
1122 		if (r)
1123 			return r;
1124 		svm_range_add_child(parent, mm, tail, SVM_OP_ADD_RANGE);
1125 	}
1126 
1127 	/* xnack on, update mapping on GPUs with ACCESS_IN_PLACE */
1128 	if (p->xnack_enabled && prange->work_item.op == SVM_OP_ADD_RANGE) {
1129 		prange->work_item.op = SVM_OP_ADD_RANGE_AND_MAP;
1130 		pr_debug("change prange 0x%p [0x%lx 0x%lx] op %d\n",
1131 			 prange, prange->start, prange->last,
1132 			 SVM_OP_ADD_RANGE_AND_MAP);
1133 	}
1134 	return 0;
1135 }
1136 static bool
1137 svm_nodes_in_same_hive(struct kfd_node *node_a, struct kfd_node *node_b)
1138 {
1139 	return (node_a->adev == node_b->adev ||
1140 		amdgpu_xgmi_same_hive(node_a->adev, node_b->adev));
1141 }
1142 
1143 static uint64_t
1144 svm_range_get_pte_flags(struct kfd_node *node,
1145 			struct svm_range *prange, int domain)
1146 {
1147 	struct kfd_node *bo_node;
1148 	uint32_t flags = prange->flags;
1149 	uint32_t mapping_flags = 0;
1150 	uint64_t pte_flags;
1151 	bool snoop = (domain != SVM_RANGE_VRAM_DOMAIN);
1152 	bool coherent = flags & KFD_IOCTL_SVM_FLAG_COHERENT;
1153 	bool uncached = flags & KFD_IOCTL_SVM_FLAG_UNCACHED;
1154 
1155 	if (domain == SVM_RANGE_VRAM_DOMAIN)
1156 		bo_node = prange->svm_bo->node;
1157 
1158 	switch (node->adev->ip_versions[GC_HWIP][0]) {
1159 	case IP_VERSION(9, 4, 1):
1160 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1161 			if (bo_node == node) {
1162 				mapping_flags |= coherent ?
1163 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1164 			} else {
1165 				mapping_flags |= coherent ?
1166 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1167 				if (svm_nodes_in_same_hive(node, bo_node))
1168 					snoop = true;
1169 			}
1170 		} else {
1171 			mapping_flags |= coherent ?
1172 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1173 		}
1174 		break;
1175 	case IP_VERSION(9, 4, 2):
1176 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1177 			if (bo_node == node) {
1178 				mapping_flags |= coherent ?
1179 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1180 				if (node->adev->gmc.xgmi.connected_to_cpu)
1181 					snoop = true;
1182 			} else {
1183 				mapping_flags |= coherent ?
1184 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1185 				if (svm_nodes_in_same_hive(node, bo_node))
1186 					snoop = true;
1187 			}
1188 		} else {
1189 			mapping_flags |= coherent ?
1190 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1191 		}
1192 		break;
1193 	case IP_VERSION(9, 4, 3):
1194 		//TODO: Need more work for handling multiple memory partitions
1195 		//e.g. NPS4. Current approch is only applicable without memory
1196 		//partitions.
1197 		snoop = true;
1198 		if (uncached) {
1199 			mapping_flags |= AMDGPU_VM_MTYPE_UC;
1200 		} else if (domain == SVM_RANGE_VRAM_DOMAIN) {
1201 			/* local HBM region close to partition */
1202 			if (bo_node == node)
1203 				mapping_flags |= AMDGPU_VM_MTYPE_RW;
1204 			/* local HBM region far from partition or remote XGMI GPU */
1205 			else if (svm_nodes_in_same_hive(bo_node, node))
1206 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1207 			/* PCIe P2P */
1208 			else
1209 				mapping_flags |= AMDGPU_VM_MTYPE_UC;
1210 		/* system memory accessed by the APU */
1211 		} else if (node->adev->flags & AMD_IS_APU) {
1212 			mapping_flags |= AMDGPU_VM_MTYPE_NC;
1213 		/* system memory accessed by the dGPU */
1214 		} else {
1215 			mapping_flags |= AMDGPU_VM_MTYPE_UC;
1216 		}
1217 		break;
1218 	default:
1219 		mapping_flags |= coherent ?
1220 			AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1221 	}
1222 
1223 	mapping_flags |= AMDGPU_VM_PAGE_READABLE | AMDGPU_VM_PAGE_WRITEABLE;
1224 
1225 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_RO)
1226 		mapping_flags &= ~AMDGPU_VM_PAGE_WRITEABLE;
1227 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_EXEC)
1228 		mapping_flags |= AMDGPU_VM_PAGE_EXECUTABLE;
1229 
1230 	pte_flags = AMDGPU_PTE_VALID;
1231 	pte_flags |= (domain == SVM_RANGE_VRAM_DOMAIN) ? 0 : AMDGPU_PTE_SYSTEM;
1232 	pte_flags |= snoop ? AMDGPU_PTE_SNOOPED : 0;
1233 
1234 	pte_flags |= amdgpu_gem_va_map_flags(node->adev, mapping_flags);
1235 	return pte_flags;
1236 }
1237 
1238 static int
1239 svm_range_unmap_from_gpu(struct amdgpu_device *adev, struct amdgpu_vm *vm,
1240 			 uint64_t start, uint64_t last,
1241 			 struct dma_fence **fence)
1242 {
1243 	uint64_t init_pte_value = 0;
1244 
1245 	pr_debug("[0x%llx 0x%llx]\n", start, last);
1246 
1247 	return amdgpu_vm_update_range(adev, vm, false, true, true, NULL, start,
1248 				      last, init_pte_value, 0, 0, NULL, NULL,
1249 				      fence);
1250 }
1251 
1252 static int
1253 svm_range_unmap_from_gpus(struct svm_range *prange, unsigned long start,
1254 			  unsigned long last, uint32_t trigger)
1255 {
1256 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1257 	struct kfd_process_device *pdd;
1258 	struct dma_fence *fence = NULL;
1259 	struct kfd_process *p;
1260 	uint32_t gpuidx;
1261 	int r = 0;
1262 
1263 	if (!prange->mapped_to_gpu) {
1264 		pr_debug("prange 0x%p [0x%lx 0x%lx] not mapped to GPU\n",
1265 			 prange, prange->start, prange->last);
1266 		return 0;
1267 	}
1268 
1269 	if (prange->start == start && prange->last == last) {
1270 		pr_debug("unmap svms 0x%p prange 0x%p\n", prange->svms, prange);
1271 		prange->mapped_to_gpu = false;
1272 	}
1273 
1274 	bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
1275 		  MAX_GPU_INSTANCE);
1276 	p = container_of(prange->svms, struct kfd_process, svms);
1277 
1278 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1279 		pr_debug("unmap from gpu idx 0x%x\n", gpuidx);
1280 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1281 		if (!pdd) {
1282 			pr_debug("failed to find device idx %d\n", gpuidx);
1283 			return -EINVAL;
1284 		}
1285 
1286 		kfd_smi_event_unmap_from_gpu(pdd->dev, p->lead_thread->pid,
1287 					     start, last, trigger);
1288 
1289 		r = svm_range_unmap_from_gpu(pdd->dev->adev,
1290 					     drm_priv_to_vm(pdd->drm_priv),
1291 					     start, last, &fence);
1292 		if (r)
1293 			break;
1294 
1295 		if (fence) {
1296 			r = dma_fence_wait(fence, false);
1297 			dma_fence_put(fence);
1298 			fence = NULL;
1299 			if (r)
1300 				break;
1301 		}
1302 		kfd_flush_tlb(pdd, TLB_FLUSH_HEAVYWEIGHT);
1303 	}
1304 
1305 	return r;
1306 }
1307 
1308 static int
1309 svm_range_map_to_gpu(struct kfd_process_device *pdd, struct svm_range *prange,
1310 		     unsigned long offset, unsigned long npages, bool readonly,
1311 		     dma_addr_t *dma_addr, struct amdgpu_device *bo_adev,
1312 		     struct dma_fence **fence, bool flush_tlb)
1313 {
1314 	struct amdgpu_device *adev = pdd->dev->adev;
1315 	struct amdgpu_vm *vm = drm_priv_to_vm(pdd->drm_priv);
1316 	uint64_t pte_flags;
1317 	unsigned long last_start;
1318 	int last_domain;
1319 	int r = 0;
1320 	int64_t i, j;
1321 
1322 	last_start = prange->start + offset;
1323 
1324 	pr_debug("svms 0x%p [0x%lx 0x%lx] readonly %d\n", prange->svms,
1325 		 last_start, last_start + npages - 1, readonly);
1326 
1327 	for (i = offset; i < offset + npages; i++) {
1328 		last_domain = dma_addr[i] & SVM_RANGE_VRAM_DOMAIN;
1329 		dma_addr[i] &= ~SVM_RANGE_VRAM_DOMAIN;
1330 
1331 		/* Collect all pages in the same address range and memory domain
1332 		 * that can be mapped with a single call to update mapping.
1333 		 */
1334 		if (i < offset + npages - 1 &&
1335 		    last_domain == (dma_addr[i + 1] & SVM_RANGE_VRAM_DOMAIN))
1336 			continue;
1337 
1338 		pr_debug("Mapping range [0x%lx 0x%llx] on domain: %s\n",
1339 			 last_start, prange->start + i, last_domain ? "GPU" : "CPU");
1340 
1341 		pte_flags = svm_range_get_pte_flags(pdd->dev, prange, last_domain);
1342 		if (readonly)
1343 			pte_flags &= ~AMDGPU_PTE_WRITEABLE;
1344 
1345 		pr_debug("svms 0x%p map [0x%lx 0x%llx] vram %d PTE 0x%llx\n",
1346 			 prange->svms, last_start, prange->start + i,
1347 			 (last_domain == SVM_RANGE_VRAM_DOMAIN) ? 1 : 0,
1348 			 pte_flags);
1349 
1350 		/* TODO: we still need to determine the vm_manager.vram_base_offset based on
1351 		 * the memory partition.
1352 		 */
1353 		r = amdgpu_vm_update_range(adev, vm, false, false, flush_tlb, NULL,
1354 					   last_start, prange->start + i,
1355 					   pte_flags,
1356 					   (last_start - prange->start) << PAGE_SHIFT,
1357 					   bo_adev ? bo_adev->vm_manager.vram_base_offset : 0,
1358 					   NULL, dma_addr, &vm->last_update);
1359 
1360 		for (j = last_start - prange->start; j <= i; j++)
1361 			dma_addr[j] |= last_domain;
1362 
1363 		if (r) {
1364 			pr_debug("failed %d to map to gpu 0x%lx\n", r, prange->start);
1365 			goto out;
1366 		}
1367 		last_start = prange->start + i + 1;
1368 	}
1369 
1370 	r = amdgpu_vm_update_pdes(adev, vm, false);
1371 	if (r) {
1372 		pr_debug("failed %d to update directories 0x%lx\n", r,
1373 			 prange->start);
1374 		goto out;
1375 	}
1376 
1377 	if (fence)
1378 		*fence = dma_fence_get(vm->last_update);
1379 
1380 out:
1381 	return r;
1382 }
1383 
1384 static int
1385 svm_range_map_to_gpus(struct svm_range *prange, unsigned long offset,
1386 		      unsigned long npages, bool readonly,
1387 		      unsigned long *bitmap, bool wait, bool flush_tlb)
1388 {
1389 	struct kfd_process_device *pdd;
1390 	struct amdgpu_device *bo_adev = NULL;
1391 	struct kfd_process *p;
1392 	struct dma_fence *fence = NULL;
1393 	uint32_t gpuidx;
1394 	int r = 0;
1395 
1396 	if (prange->svm_bo && prange->ttm_res)
1397 		bo_adev = prange->svm_bo->node->adev;
1398 
1399 	p = container_of(prange->svms, struct kfd_process, svms);
1400 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1401 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
1402 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1403 		if (!pdd) {
1404 			pr_debug("failed to find device idx %d\n", gpuidx);
1405 			return -EINVAL;
1406 		}
1407 
1408 		pdd = kfd_bind_process_to_device(pdd->dev, p);
1409 		if (IS_ERR(pdd))
1410 			return -EINVAL;
1411 
1412 		if (bo_adev && pdd->dev->adev != bo_adev &&
1413 		    !amdgpu_xgmi_same_hive(pdd->dev->adev, bo_adev)) {
1414 			pr_debug("cannot map to device idx %d\n", gpuidx);
1415 			continue;
1416 		}
1417 
1418 		r = svm_range_map_to_gpu(pdd, prange, offset, npages, readonly,
1419 					 prange->dma_addr[gpuidx],
1420 					 bo_adev, wait ? &fence : NULL,
1421 					 flush_tlb);
1422 		if (r)
1423 			break;
1424 
1425 		if (fence) {
1426 			r = dma_fence_wait(fence, false);
1427 			dma_fence_put(fence);
1428 			fence = NULL;
1429 			if (r) {
1430 				pr_debug("failed %d to dma fence wait\n", r);
1431 				break;
1432 			}
1433 		}
1434 
1435 		kfd_flush_tlb(pdd, TLB_FLUSH_LEGACY);
1436 	}
1437 
1438 	return r;
1439 }
1440 
1441 struct svm_validate_context {
1442 	struct kfd_process *process;
1443 	struct svm_range *prange;
1444 	bool intr;
1445 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1446 	struct ttm_validate_buffer tv[MAX_GPU_INSTANCE];
1447 	struct list_head validate_list;
1448 	struct ww_acquire_ctx ticket;
1449 };
1450 
1451 static int svm_range_reserve_bos(struct svm_validate_context *ctx)
1452 {
1453 	struct kfd_process_device *pdd;
1454 	struct amdgpu_vm *vm;
1455 	uint32_t gpuidx;
1456 	int r;
1457 
1458 	INIT_LIST_HEAD(&ctx->validate_list);
1459 	for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1460 		pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1461 		if (!pdd) {
1462 			pr_debug("failed to find device idx %d\n", gpuidx);
1463 			return -EINVAL;
1464 		}
1465 		vm = drm_priv_to_vm(pdd->drm_priv);
1466 
1467 		ctx->tv[gpuidx].bo = &vm->root.bo->tbo;
1468 		ctx->tv[gpuidx].num_shared = 4;
1469 		list_add(&ctx->tv[gpuidx].head, &ctx->validate_list);
1470 	}
1471 
1472 	r = ttm_eu_reserve_buffers(&ctx->ticket, &ctx->validate_list,
1473 				   ctx->intr, NULL);
1474 	if (r) {
1475 		pr_debug("failed %d to reserve bo\n", r);
1476 		return r;
1477 	}
1478 
1479 	for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1480 		pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1481 		if (!pdd) {
1482 			pr_debug("failed to find device idx %d\n", gpuidx);
1483 			r = -EINVAL;
1484 			goto unreserve_out;
1485 		}
1486 
1487 		r = amdgpu_vm_validate_pt_bos(pdd->dev->adev,
1488 					      drm_priv_to_vm(pdd->drm_priv),
1489 					      svm_range_bo_validate, NULL);
1490 		if (r) {
1491 			pr_debug("failed %d validate pt bos\n", r);
1492 			goto unreserve_out;
1493 		}
1494 	}
1495 
1496 	return 0;
1497 
1498 unreserve_out:
1499 	ttm_eu_backoff_reservation(&ctx->ticket, &ctx->validate_list);
1500 	return r;
1501 }
1502 
1503 static void svm_range_unreserve_bos(struct svm_validate_context *ctx)
1504 {
1505 	ttm_eu_backoff_reservation(&ctx->ticket, &ctx->validate_list);
1506 }
1507 
1508 static void *kfd_svm_page_owner(struct kfd_process *p, int32_t gpuidx)
1509 {
1510 	struct kfd_process_device *pdd;
1511 
1512 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1513 
1514 	return SVM_ADEV_PGMAP_OWNER(pdd->dev->adev);
1515 }
1516 
1517 /*
1518  * Validation+GPU mapping with concurrent invalidation (MMU notifiers)
1519  *
1520  * To prevent concurrent destruction or change of range attributes, the
1521  * svm_read_lock must be held. The caller must not hold the svm_write_lock
1522  * because that would block concurrent evictions and lead to deadlocks. To
1523  * serialize concurrent migrations or validations of the same range, the
1524  * prange->migrate_mutex must be held.
1525  *
1526  * For VRAM ranges, the SVM BO must be allocated and valid (protected by its
1527  * eviction fence.
1528  *
1529  * The following sequence ensures race-free validation and GPU mapping:
1530  *
1531  * 1. Reserve page table (and SVM BO if range is in VRAM)
1532  * 2. hmm_range_fault to get page addresses (if system memory)
1533  * 3. DMA-map pages (if system memory)
1534  * 4-a. Take notifier lock
1535  * 4-b. Check that pages still valid (mmu_interval_read_retry)
1536  * 4-c. Check that the range was not split or otherwise invalidated
1537  * 4-d. Update GPU page table
1538  * 4.e. Release notifier lock
1539  * 5. Release page table (and SVM BO) reservation
1540  */
1541 static int svm_range_validate_and_map(struct mm_struct *mm,
1542 				      struct svm_range *prange, int32_t gpuidx,
1543 				      bool intr, bool wait, bool flush_tlb)
1544 {
1545 	struct svm_validate_context ctx;
1546 	unsigned long start, end, addr;
1547 	struct kfd_process *p;
1548 	void *owner;
1549 	int32_t idx;
1550 	int r = 0;
1551 
1552 	ctx.process = container_of(prange->svms, struct kfd_process, svms);
1553 	ctx.prange = prange;
1554 	ctx.intr = intr;
1555 
1556 	if (gpuidx < MAX_GPU_INSTANCE) {
1557 		bitmap_zero(ctx.bitmap, MAX_GPU_INSTANCE);
1558 		bitmap_set(ctx.bitmap, gpuidx, 1);
1559 	} else if (ctx.process->xnack_enabled) {
1560 		bitmap_copy(ctx.bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
1561 
1562 		/* If prefetch range to GPU, or GPU retry fault migrate range to
1563 		 * GPU, which has ACCESS attribute to the range, create mapping
1564 		 * on that GPU.
1565 		 */
1566 		if (prange->actual_loc) {
1567 			gpuidx = kfd_process_gpuidx_from_gpuid(ctx.process,
1568 							prange->actual_loc);
1569 			if (gpuidx < 0) {
1570 				WARN_ONCE(1, "failed get device by id 0x%x\n",
1571 					 prange->actual_loc);
1572 				return -EINVAL;
1573 			}
1574 			if (test_bit(gpuidx, prange->bitmap_access))
1575 				bitmap_set(ctx.bitmap, gpuidx, 1);
1576 		}
1577 	} else {
1578 		bitmap_or(ctx.bitmap, prange->bitmap_access,
1579 			  prange->bitmap_aip, MAX_GPU_INSTANCE);
1580 	}
1581 
1582 	if (bitmap_empty(ctx.bitmap, MAX_GPU_INSTANCE)) {
1583 		if (!prange->mapped_to_gpu)
1584 			return 0;
1585 
1586 		bitmap_copy(ctx.bitmap, prange->bitmap_access, MAX_GPU_INSTANCE);
1587 	}
1588 
1589 	if (prange->actual_loc && !prange->ttm_res) {
1590 		/* This should never happen. actual_loc gets set by
1591 		 * svm_migrate_ram_to_vram after allocating a BO.
1592 		 */
1593 		WARN_ONCE(1, "VRAM BO missing during validation\n");
1594 		return -EINVAL;
1595 	}
1596 
1597 	svm_range_reserve_bos(&ctx);
1598 
1599 	p = container_of(prange->svms, struct kfd_process, svms);
1600 	owner = kfd_svm_page_owner(p, find_first_bit(ctx.bitmap,
1601 						MAX_GPU_INSTANCE));
1602 	for_each_set_bit(idx, ctx.bitmap, MAX_GPU_INSTANCE) {
1603 		if (kfd_svm_page_owner(p, idx) != owner) {
1604 			owner = NULL;
1605 			break;
1606 		}
1607 	}
1608 
1609 	start = prange->start << PAGE_SHIFT;
1610 	end = (prange->last + 1) << PAGE_SHIFT;
1611 	for (addr = start; addr < end && !r; ) {
1612 		struct hmm_range *hmm_range;
1613 		struct vm_area_struct *vma;
1614 		unsigned long next;
1615 		unsigned long offset;
1616 		unsigned long npages;
1617 		bool readonly;
1618 
1619 		vma = vma_lookup(mm, addr);
1620 		if (!vma) {
1621 			r = -EFAULT;
1622 			goto unreserve_out;
1623 		}
1624 		readonly = !(vma->vm_flags & VM_WRITE);
1625 
1626 		next = min(vma->vm_end, end);
1627 		npages = (next - addr) >> PAGE_SHIFT;
1628 		WRITE_ONCE(p->svms.faulting_task, current);
1629 		r = amdgpu_hmm_range_get_pages(&prange->notifier, addr, npages,
1630 					       readonly, owner, NULL,
1631 					       &hmm_range);
1632 		WRITE_ONCE(p->svms.faulting_task, NULL);
1633 		if (r) {
1634 			pr_debug("failed %d to get svm range pages\n", r);
1635 			goto unreserve_out;
1636 		}
1637 
1638 		offset = (addr - start) >> PAGE_SHIFT;
1639 		r = svm_range_dma_map(prange, ctx.bitmap, offset, npages,
1640 				      hmm_range->hmm_pfns);
1641 		if (r) {
1642 			pr_debug("failed %d to dma map range\n", r);
1643 			goto unreserve_out;
1644 		}
1645 
1646 		svm_range_lock(prange);
1647 		if (amdgpu_hmm_range_get_pages_done(hmm_range)) {
1648 			pr_debug("hmm update the range, need validate again\n");
1649 			r = -EAGAIN;
1650 			goto unlock_out;
1651 		}
1652 		if (!list_empty(&prange->child_list)) {
1653 			pr_debug("range split by unmap in parallel, validate again\n");
1654 			r = -EAGAIN;
1655 			goto unlock_out;
1656 		}
1657 
1658 		r = svm_range_map_to_gpus(prange, offset, npages, readonly,
1659 					  ctx.bitmap, wait, flush_tlb);
1660 
1661 unlock_out:
1662 		svm_range_unlock(prange);
1663 
1664 		addr = next;
1665 	}
1666 
1667 	if (addr == end) {
1668 		prange->validated_once = true;
1669 		prange->mapped_to_gpu = true;
1670 	}
1671 
1672 unreserve_out:
1673 	svm_range_unreserve_bos(&ctx);
1674 
1675 	if (!r)
1676 		prange->validate_timestamp = ktime_get_boottime();
1677 
1678 	return r;
1679 }
1680 
1681 /**
1682  * svm_range_list_lock_and_flush_work - flush pending deferred work
1683  *
1684  * @svms: the svm range list
1685  * @mm: the mm structure
1686  *
1687  * Context: Returns with mmap write lock held, pending deferred work flushed
1688  *
1689  */
1690 void
1691 svm_range_list_lock_and_flush_work(struct svm_range_list *svms,
1692 				   struct mm_struct *mm)
1693 {
1694 retry_flush_work:
1695 	flush_work(&svms->deferred_list_work);
1696 	mmap_write_lock(mm);
1697 
1698 	if (list_empty(&svms->deferred_range_list))
1699 		return;
1700 	mmap_write_unlock(mm);
1701 	pr_debug("retry flush\n");
1702 	goto retry_flush_work;
1703 }
1704 
1705 static void svm_range_restore_work(struct work_struct *work)
1706 {
1707 	struct delayed_work *dwork = to_delayed_work(work);
1708 	struct amdkfd_process_info *process_info;
1709 	struct svm_range_list *svms;
1710 	struct svm_range *prange;
1711 	struct kfd_process *p;
1712 	struct mm_struct *mm;
1713 	int evicted_ranges;
1714 	int invalid;
1715 	int r;
1716 
1717 	svms = container_of(dwork, struct svm_range_list, restore_work);
1718 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1719 	if (!evicted_ranges)
1720 		return;
1721 
1722 	pr_debug("restore svm ranges\n");
1723 
1724 	p = container_of(svms, struct kfd_process, svms);
1725 	process_info = p->kgd_process_info;
1726 
1727 	/* Keep mm reference when svm_range_validate_and_map ranges */
1728 	mm = get_task_mm(p->lead_thread);
1729 	if (!mm) {
1730 		pr_debug("svms 0x%p process mm gone\n", svms);
1731 		return;
1732 	}
1733 
1734 	mutex_lock(&process_info->lock);
1735 	svm_range_list_lock_and_flush_work(svms, mm);
1736 	mutex_lock(&svms->lock);
1737 
1738 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1739 
1740 	list_for_each_entry(prange, &svms->list, list) {
1741 		invalid = atomic_read(&prange->invalid);
1742 		if (!invalid)
1743 			continue;
1744 
1745 		pr_debug("restoring svms 0x%p prange 0x%p [0x%lx %lx] inv %d\n",
1746 			 prange->svms, prange, prange->start, prange->last,
1747 			 invalid);
1748 
1749 		/*
1750 		 * If range is migrating, wait for migration is done.
1751 		 */
1752 		mutex_lock(&prange->migrate_mutex);
1753 
1754 		r = svm_range_validate_and_map(mm, prange, MAX_GPU_INSTANCE,
1755 					       false, true, false);
1756 		if (r)
1757 			pr_debug("failed %d to map 0x%lx to gpus\n", r,
1758 				 prange->start);
1759 
1760 		mutex_unlock(&prange->migrate_mutex);
1761 		if (r)
1762 			goto out_reschedule;
1763 
1764 		if (atomic_cmpxchg(&prange->invalid, invalid, 0) != invalid)
1765 			goto out_reschedule;
1766 	}
1767 
1768 	if (atomic_cmpxchg(&svms->evicted_ranges, evicted_ranges, 0) !=
1769 	    evicted_ranges)
1770 		goto out_reschedule;
1771 
1772 	evicted_ranges = 0;
1773 
1774 	r = kgd2kfd_resume_mm(mm);
1775 	if (r) {
1776 		/* No recovery from this failure. Probably the CP is
1777 		 * hanging. No point trying again.
1778 		 */
1779 		pr_debug("failed %d to resume KFD\n", r);
1780 	}
1781 
1782 	pr_debug("restore svm ranges successfully\n");
1783 
1784 out_reschedule:
1785 	mutex_unlock(&svms->lock);
1786 	mmap_write_unlock(mm);
1787 	mutex_unlock(&process_info->lock);
1788 
1789 	/* If validation failed, reschedule another attempt */
1790 	if (evicted_ranges) {
1791 		pr_debug("reschedule to restore svm range\n");
1792 		schedule_delayed_work(&svms->restore_work,
1793 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1794 
1795 		kfd_smi_event_queue_restore_rescheduled(mm);
1796 	}
1797 	mmput(mm);
1798 }
1799 
1800 /**
1801  * svm_range_evict - evict svm range
1802  * @prange: svm range structure
1803  * @mm: current process mm_struct
1804  * @start: starting process queue number
1805  * @last: last process queue number
1806  *
1807  * Stop all queues of the process to ensure GPU doesn't access the memory, then
1808  * return to let CPU evict the buffer and proceed CPU pagetable update.
1809  *
1810  * Don't need use lock to sync cpu pagetable invalidation with GPU execution.
1811  * If invalidation happens while restore work is running, restore work will
1812  * restart to ensure to get the latest CPU pages mapping to GPU, then start
1813  * the queues.
1814  */
1815 static int
1816 svm_range_evict(struct svm_range *prange, struct mm_struct *mm,
1817 		unsigned long start, unsigned long last,
1818 		enum mmu_notifier_event event)
1819 {
1820 	struct svm_range_list *svms = prange->svms;
1821 	struct svm_range *pchild;
1822 	struct kfd_process *p;
1823 	int r = 0;
1824 
1825 	p = container_of(svms, struct kfd_process, svms);
1826 
1827 	pr_debug("invalidate svms 0x%p prange [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
1828 		 svms, prange->start, prange->last, start, last);
1829 
1830 	if (!p->xnack_enabled ||
1831 	    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) {
1832 		int evicted_ranges;
1833 		bool mapped = prange->mapped_to_gpu;
1834 
1835 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1836 			if (!pchild->mapped_to_gpu)
1837 				continue;
1838 			mapped = true;
1839 			mutex_lock_nested(&pchild->lock, 1);
1840 			if (pchild->start <= last && pchild->last >= start) {
1841 				pr_debug("increment pchild invalid [0x%lx 0x%lx]\n",
1842 					 pchild->start, pchild->last);
1843 				atomic_inc(&pchild->invalid);
1844 			}
1845 			mutex_unlock(&pchild->lock);
1846 		}
1847 
1848 		if (!mapped)
1849 			return r;
1850 
1851 		if (prange->start <= last && prange->last >= start)
1852 			atomic_inc(&prange->invalid);
1853 
1854 		evicted_ranges = atomic_inc_return(&svms->evicted_ranges);
1855 		if (evicted_ranges != 1)
1856 			return r;
1857 
1858 		pr_debug("evicting svms 0x%p range [0x%lx 0x%lx]\n",
1859 			 prange->svms, prange->start, prange->last);
1860 
1861 		/* First eviction, stop the queues */
1862 		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_SVM);
1863 		if (r)
1864 			pr_debug("failed to quiesce KFD\n");
1865 
1866 		pr_debug("schedule to restore svm %p ranges\n", svms);
1867 		schedule_delayed_work(&svms->restore_work,
1868 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1869 	} else {
1870 		unsigned long s, l;
1871 		uint32_t trigger;
1872 
1873 		if (event == MMU_NOTIFY_MIGRATE)
1874 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY_MIGRATE;
1875 		else
1876 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY;
1877 
1878 		pr_debug("invalidate unmap svms 0x%p [0x%lx 0x%lx] from GPUs\n",
1879 			 prange->svms, start, last);
1880 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1881 			mutex_lock_nested(&pchild->lock, 1);
1882 			s = max(start, pchild->start);
1883 			l = min(last, pchild->last);
1884 			if (l >= s)
1885 				svm_range_unmap_from_gpus(pchild, s, l, trigger);
1886 			mutex_unlock(&pchild->lock);
1887 		}
1888 		s = max(start, prange->start);
1889 		l = min(last, prange->last);
1890 		if (l >= s)
1891 			svm_range_unmap_from_gpus(prange, s, l, trigger);
1892 	}
1893 
1894 	return r;
1895 }
1896 
1897 static struct svm_range *svm_range_clone(struct svm_range *old)
1898 {
1899 	struct svm_range *new;
1900 
1901 	new = svm_range_new(old->svms, old->start, old->last, false);
1902 	if (!new)
1903 		return NULL;
1904 
1905 	if (old->svm_bo) {
1906 		new->ttm_res = old->ttm_res;
1907 		new->offset = old->offset;
1908 		new->svm_bo = svm_range_bo_ref(old->svm_bo);
1909 		spin_lock(&new->svm_bo->list_lock);
1910 		list_add(&new->svm_bo_list, &new->svm_bo->range_list);
1911 		spin_unlock(&new->svm_bo->list_lock);
1912 	}
1913 	new->flags = old->flags;
1914 	new->preferred_loc = old->preferred_loc;
1915 	new->prefetch_loc = old->prefetch_loc;
1916 	new->actual_loc = old->actual_loc;
1917 	new->granularity = old->granularity;
1918 	new->mapped_to_gpu = old->mapped_to_gpu;
1919 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
1920 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
1921 
1922 	return new;
1923 }
1924 
1925 void svm_range_set_max_pages(struct amdgpu_device *adev)
1926 {
1927 	uint64_t max_pages;
1928 	uint64_t pages, _pages;
1929 
1930 	/* 1/32 VRAM size in pages */
1931 	pages = adev->gmc.real_vram_size >> 17;
1932 	pages = clamp(pages, 1ULL << 9, 1ULL << 18);
1933 	pages = rounddown_pow_of_two(pages);
1934 	do {
1935 		max_pages = READ_ONCE(max_svm_range_pages);
1936 		_pages = min_not_zero(max_pages, pages);
1937 	} while (cmpxchg(&max_svm_range_pages, max_pages, _pages) != max_pages);
1938 }
1939 
1940 static int
1941 svm_range_split_new(struct svm_range_list *svms, uint64_t start, uint64_t last,
1942 		    uint64_t max_pages, struct list_head *insert_list,
1943 		    struct list_head *update_list)
1944 {
1945 	struct svm_range *prange;
1946 	uint64_t l;
1947 
1948 	pr_debug("max_svm_range_pages 0x%llx adding [0x%llx 0x%llx]\n",
1949 		 max_pages, start, last);
1950 
1951 	while (last >= start) {
1952 		l = min(last, ALIGN_DOWN(start + max_pages, max_pages) - 1);
1953 
1954 		prange = svm_range_new(svms, start, l, true);
1955 		if (!prange)
1956 			return -ENOMEM;
1957 		list_add(&prange->list, insert_list);
1958 		list_add(&prange->update_list, update_list);
1959 
1960 		start = l + 1;
1961 	}
1962 	return 0;
1963 }
1964 
1965 /**
1966  * svm_range_add - add svm range and handle overlap
1967  * @p: the range add to this process svms
1968  * @start: page size aligned
1969  * @size: page size aligned
1970  * @nattr: number of attributes
1971  * @attrs: array of attributes
1972  * @update_list: output, the ranges need validate and update GPU mapping
1973  * @insert_list: output, the ranges need insert to svms
1974  * @remove_list: output, the ranges are replaced and need remove from svms
1975  *
1976  * Check if the virtual address range has overlap with any existing ranges,
1977  * split partly overlapping ranges and add new ranges in the gaps. All changes
1978  * should be applied to the range_list and interval tree transactionally. If
1979  * any range split or allocation fails, the entire update fails. Therefore any
1980  * existing overlapping svm_ranges are cloned and the original svm_ranges left
1981  * unchanged.
1982  *
1983  * If the transaction succeeds, the caller can update and insert clones and
1984  * new ranges, then free the originals.
1985  *
1986  * Otherwise the caller can free the clones and new ranges, while the old
1987  * svm_ranges remain unchanged.
1988  *
1989  * Context: Process context, caller must hold svms->lock
1990  *
1991  * Return:
1992  * 0 - OK, otherwise error code
1993  */
1994 static int
1995 svm_range_add(struct kfd_process *p, uint64_t start, uint64_t size,
1996 	      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
1997 	      struct list_head *update_list, struct list_head *insert_list,
1998 	      struct list_head *remove_list)
1999 {
2000 	unsigned long last = start + size - 1UL;
2001 	struct svm_range_list *svms = &p->svms;
2002 	struct interval_tree_node *node;
2003 	struct svm_range *prange;
2004 	struct svm_range *tmp;
2005 	struct list_head new_list;
2006 	int r = 0;
2007 
2008 	pr_debug("svms 0x%p [0x%llx 0x%lx]\n", &p->svms, start, last);
2009 
2010 	INIT_LIST_HEAD(update_list);
2011 	INIT_LIST_HEAD(insert_list);
2012 	INIT_LIST_HEAD(remove_list);
2013 	INIT_LIST_HEAD(&new_list);
2014 
2015 	node = interval_tree_iter_first(&svms->objects, start, last);
2016 	while (node) {
2017 		struct interval_tree_node *next;
2018 		unsigned long next_start;
2019 
2020 		pr_debug("found overlap node [0x%lx 0x%lx]\n", node->start,
2021 			 node->last);
2022 
2023 		prange = container_of(node, struct svm_range, it_node);
2024 		next = interval_tree_iter_next(node, start, last);
2025 		next_start = min(node->last, last) + 1;
2026 
2027 		if (svm_range_is_same_attrs(p, prange, nattr, attrs)) {
2028 			/* nothing to do */
2029 		} else if (node->start < start || node->last > last) {
2030 			/* node intersects the update range and its attributes
2031 			 * will change. Clone and split it, apply updates only
2032 			 * to the overlapping part
2033 			 */
2034 			struct svm_range *old = prange;
2035 
2036 			prange = svm_range_clone(old);
2037 			if (!prange) {
2038 				r = -ENOMEM;
2039 				goto out;
2040 			}
2041 
2042 			list_add(&old->update_list, remove_list);
2043 			list_add(&prange->list, insert_list);
2044 			list_add(&prange->update_list, update_list);
2045 
2046 			if (node->start < start) {
2047 				pr_debug("change old range start\n");
2048 				r = svm_range_split_head(prange, start,
2049 							 insert_list);
2050 				if (r)
2051 					goto out;
2052 			}
2053 			if (node->last > last) {
2054 				pr_debug("change old range last\n");
2055 				r = svm_range_split_tail(prange, last,
2056 							 insert_list);
2057 				if (r)
2058 					goto out;
2059 			}
2060 		} else {
2061 			/* The node is contained within start..last,
2062 			 * just update it
2063 			 */
2064 			list_add(&prange->update_list, update_list);
2065 		}
2066 
2067 		/* insert a new node if needed */
2068 		if (node->start > start) {
2069 			r = svm_range_split_new(svms, start, node->start - 1,
2070 						READ_ONCE(max_svm_range_pages),
2071 						&new_list, update_list);
2072 			if (r)
2073 				goto out;
2074 		}
2075 
2076 		node = next;
2077 		start = next_start;
2078 	}
2079 
2080 	/* add a final range at the end if needed */
2081 	if (start <= last)
2082 		r = svm_range_split_new(svms, start, last,
2083 					READ_ONCE(max_svm_range_pages),
2084 					&new_list, update_list);
2085 
2086 out:
2087 	if (r) {
2088 		list_for_each_entry_safe(prange, tmp, insert_list, list)
2089 			svm_range_free(prange, false);
2090 		list_for_each_entry_safe(prange, tmp, &new_list, list)
2091 			svm_range_free(prange, true);
2092 	} else {
2093 		list_splice(&new_list, insert_list);
2094 	}
2095 
2096 	return r;
2097 }
2098 
2099 static void
2100 svm_range_update_notifier_and_interval_tree(struct mm_struct *mm,
2101 					    struct svm_range *prange)
2102 {
2103 	unsigned long start;
2104 	unsigned long last;
2105 
2106 	start = prange->notifier.interval_tree.start >> PAGE_SHIFT;
2107 	last = prange->notifier.interval_tree.last >> PAGE_SHIFT;
2108 
2109 	if (prange->start == start && prange->last == last)
2110 		return;
2111 
2112 	pr_debug("up notifier 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
2113 		  prange->svms, prange, start, last, prange->start,
2114 		  prange->last);
2115 
2116 	if (start != 0 && last != 0) {
2117 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
2118 		svm_range_remove_notifier(prange);
2119 	}
2120 	prange->it_node.start = prange->start;
2121 	prange->it_node.last = prange->last;
2122 
2123 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
2124 	svm_range_add_notifier_locked(mm, prange);
2125 }
2126 
2127 static void
2128 svm_range_handle_list_op(struct svm_range_list *svms, struct svm_range *prange,
2129 			 struct mm_struct *mm)
2130 {
2131 	switch (prange->work_item.op) {
2132 	case SVM_OP_NULL:
2133 		pr_debug("NULL OP 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2134 			 svms, prange, prange->start, prange->last);
2135 		break;
2136 	case SVM_OP_UNMAP_RANGE:
2137 		pr_debug("remove 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2138 			 svms, prange, prange->start, prange->last);
2139 		svm_range_unlink(prange);
2140 		svm_range_remove_notifier(prange);
2141 		svm_range_free(prange, true);
2142 		break;
2143 	case SVM_OP_UPDATE_RANGE_NOTIFIER:
2144 		pr_debug("update notifier 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2145 			 svms, prange, prange->start, prange->last);
2146 		svm_range_update_notifier_and_interval_tree(mm, prange);
2147 		break;
2148 	case SVM_OP_UPDATE_RANGE_NOTIFIER_AND_MAP:
2149 		pr_debug("update and map 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2150 			 svms, prange, prange->start, prange->last);
2151 		svm_range_update_notifier_and_interval_tree(mm, prange);
2152 		/* TODO: implement deferred validation and mapping */
2153 		break;
2154 	case SVM_OP_ADD_RANGE:
2155 		pr_debug("add 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms, prange,
2156 			 prange->start, prange->last);
2157 		svm_range_add_to_svms(prange);
2158 		svm_range_add_notifier_locked(mm, prange);
2159 		break;
2160 	case SVM_OP_ADD_RANGE_AND_MAP:
2161 		pr_debug("add and map 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms,
2162 			 prange, prange->start, prange->last);
2163 		svm_range_add_to_svms(prange);
2164 		svm_range_add_notifier_locked(mm, prange);
2165 		/* TODO: implement deferred validation and mapping */
2166 		break;
2167 	default:
2168 		WARN_ONCE(1, "Unknown prange 0x%p work op %d\n", prange,
2169 			 prange->work_item.op);
2170 	}
2171 }
2172 
2173 static void svm_range_drain_retry_fault(struct svm_range_list *svms)
2174 {
2175 	struct kfd_process_device *pdd;
2176 	struct kfd_process *p;
2177 	int drain;
2178 	uint32_t i;
2179 
2180 	p = container_of(svms, struct kfd_process, svms);
2181 
2182 restart:
2183 	drain = atomic_read(&svms->drain_pagefaults);
2184 	if (!drain)
2185 		return;
2186 
2187 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2188 		pdd = p->pdds[i];
2189 		if (!pdd)
2190 			continue;
2191 
2192 		pr_debug("drain retry fault gpu %d svms %p\n", i, svms);
2193 
2194 		amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2195 				pdd->dev->adev->irq.retry_cam_enabled ?
2196 				&pdd->dev->adev->irq.ih :
2197 				&pdd->dev->adev->irq.ih1);
2198 
2199 		if (pdd->dev->adev->irq.retry_cam_enabled)
2200 			amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2201 				&pdd->dev->adev->irq.ih_soft);
2202 
2203 
2204 		pr_debug("drain retry fault gpu %d svms 0x%p done\n", i, svms);
2205 	}
2206 	if (atomic_cmpxchg(&svms->drain_pagefaults, drain, 0) != drain)
2207 		goto restart;
2208 }
2209 
2210 static void svm_range_deferred_list_work(struct work_struct *work)
2211 {
2212 	struct svm_range_list *svms;
2213 	struct svm_range *prange;
2214 	struct mm_struct *mm;
2215 
2216 	svms = container_of(work, struct svm_range_list, deferred_list_work);
2217 	pr_debug("enter svms 0x%p\n", svms);
2218 
2219 	spin_lock(&svms->deferred_list_lock);
2220 	while (!list_empty(&svms->deferred_range_list)) {
2221 		prange = list_first_entry(&svms->deferred_range_list,
2222 					  struct svm_range, deferred_list);
2223 		spin_unlock(&svms->deferred_list_lock);
2224 
2225 		pr_debug("prange 0x%p [0x%lx 0x%lx] op %d\n", prange,
2226 			 prange->start, prange->last, prange->work_item.op);
2227 
2228 		mm = prange->work_item.mm;
2229 retry:
2230 		mmap_write_lock(mm);
2231 
2232 		/* Checking for the need to drain retry faults must be inside
2233 		 * mmap write lock to serialize with munmap notifiers.
2234 		 */
2235 		if (unlikely(atomic_read(&svms->drain_pagefaults))) {
2236 			mmap_write_unlock(mm);
2237 			svm_range_drain_retry_fault(svms);
2238 			goto retry;
2239 		}
2240 
2241 		/* Remove from deferred_list must be inside mmap write lock, for
2242 		 * two race cases:
2243 		 * 1. unmap_from_cpu may change work_item.op and add the range
2244 		 *    to deferred_list again, cause use after free bug.
2245 		 * 2. svm_range_list_lock_and_flush_work may hold mmap write
2246 		 *    lock and continue because deferred_list is empty, but
2247 		 *    deferred_list work is actually waiting for mmap lock.
2248 		 */
2249 		spin_lock(&svms->deferred_list_lock);
2250 		list_del_init(&prange->deferred_list);
2251 		spin_unlock(&svms->deferred_list_lock);
2252 
2253 		mutex_lock(&svms->lock);
2254 		mutex_lock(&prange->migrate_mutex);
2255 		while (!list_empty(&prange->child_list)) {
2256 			struct svm_range *pchild;
2257 
2258 			pchild = list_first_entry(&prange->child_list,
2259 						struct svm_range, child_list);
2260 			pr_debug("child prange 0x%p op %d\n", pchild,
2261 				 pchild->work_item.op);
2262 			list_del_init(&pchild->child_list);
2263 			svm_range_handle_list_op(svms, pchild, mm);
2264 		}
2265 		mutex_unlock(&prange->migrate_mutex);
2266 
2267 		svm_range_handle_list_op(svms, prange, mm);
2268 		mutex_unlock(&svms->lock);
2269 		mmap_write_unlock(mm);
2270 
2271 		/* Pairs with mmget in svm_range_add_list_work */
2272 		mmput(mm);
2273 
2274 		spin_lock(&svms->deferred_list_lock);
2275 	}
2276 	spin_unlock(&svms->deferred_list_lock);
2277 	pr_debug("exit svms 0x%p\n", svms);
2278 }
2279 
2280 void
2281 svm_range_add_list_work(struct svm_range_list *svms, struct svm_range *prange,
2282 			struct mm_struct *mm, enum svm_work_list_ops op)
2283 {
2284 	spin_lock(&svms->deferred_list_lock);
2285 	/* if prange is on the deferred list */
2286 	if (!list_empty(&prange->deferred_list)) {
2287 		pr_debug("update exist prange 0x%p work op %d\n", prange, op);
2288 		WARN_ONCE(prange->work_item.mm != mm, "unmatch mm\n");
2289 		if (op != SVM_OP_NULL &&
2290 		    prange->work_item.op != SVM_OP_UNMAP_RANGE)
2291 			prange->work_item.op = op;
2292 	} else {
2293 		prange->work_item.op = op;
2294 
2295 		/* Pairs with mmput in deferred_list_work */
2296 		mmget(mm);
2297 		prange->work_item.mm = mm;
2298 		list_add_tail(&prange->deferred_list,
2299 			      &prange->svms->deferred_range_list);
2300 		pr_debug("add prange 0x%p [0x%lx 0x%lx] to work list op %d\n",
2301 			 prange, prange->start, prange->last, op);
2302 	}
2303 	spin_unlock(&svms->deferred_list_lock);
2304 }
2305 
2306 void schedule_deferred_list_work(struct svm_range_list *svms)
2307 {
2308 	spin_lock(&svms->deferred_list_lock);
2309 	if (!list_empty(&svms->deferred_range_list))
2310 		schedule_work(&svms->deferred_list_work);
2311 	spin_unlock(&svms->deferred_list_lock);
2312 }
2313 
2314 static void
2315 svm_range_unmap_split(struct mm_struct *mm, struct svm_range *parent,
2316 		      struct svm_range *prange, unsigned long start,
2317 		      unsigned long last)
2318 {
2319 	struct svm_range *head;
2320 	struct svm_range *tail;
2321 
2322 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2323 		pr_debug("prange 0x%p [0x%lx 0x%lx] is already freed\n", prange,
2324 			 prange->start, prange->last);
2325 		return;
2326 	}
2327 	if (start > prange->last || last < prange->start)
2328 		return;
2329 
2330 	head = tail = prange;
2331 	if (start > prange->start)
2332 		svm_range_split(prange, prange->start, start - 1, &tail);
2333 	if (last < tail->last)
2334 		svm_range_split(tail, last + 1, tail->last, &head);
2335 
2336 	if (head != prange && tail != prange) {
2337 		svm_range_add_child(parent, mm, head, SVM_OP_UNMAP_RANGE);
2338 		svm_range_add_child(parent, mm, tail, SVM_OP_ADD_RANGE);
2339 	} else if (tail != prange) {
2340 		svm_range_add_child(parent, mm, tail, SVM_OP_UNMAP_RANGE);
2341 	} else if (head != prange) {
2342 		svm_range_add_child(parent, mm, head, SVM_OP_UNMAP_RANGE);
2343 	} else if (parent != prange) {
2344 		prange->work_item.op = SVM_OP_UNMAP_RANGE;
2345 	}
2346 }
2347 
2348 static void
2349 svm_range_unmap_from_cpu(struct mm_struct *mm, struct svm_range *prange,
2350 			 unsigned long start, unsigned long last)
2351 {
2352 	uint32_t trigger = KFD_SVM_UNMAP_TRIGGER_UNMAP_FROM_CPU;
2353 	struct svm_range_list *svms;
2354 	struct svm_range *pchild;
2355 	struct kfd_process *p;
2356 	unsigned long s, l;
2357 	bool unmap_parent;
2358 
2359 	p = kfd_lookup_process_by_mm(mm);
2360 	if (!p)
2361 		return;
2362 	svms = &p->svms;
2363 
2364 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n", svms,
2365 		 prange, prange->start, prange->last, start, last);
2366 
2367 	/* Make sure pending page faults are drained in the deferred worker
2368 	 * before the range is freed to avoid straggler interrupts on
2369 	 * unmapped memory causing "phantom faults".
2370 	 */
2371 	atomic_inc(&svms->drain_pagefaults);
2372 
2373 	unmap_parent = start <= prange->start && last >= prange->last;
2374 
2375 	list_for_each_entry(pchild, &prange->child_list, child_list) {
2376 		mutex_lock_nested(&pchild->lock, 1);
2377 		s = max(start, pchild->start);
2378 		l = min(last, pchild->last);
2379 		if (l >= s)
2380 			svm_range_unmap_from_gpus(pchild, s, l, trigger);
2381 		svm_range_unmap_split(mm, prange, pchild, start, last);
2382 		mutex_unlock(&pchild->lock);
2383 	}
2384 	s = max(start, prange->start);
2385 	l = min(last, prange->last);
2386 	if (l >= s)
2387 		svm_range_unmap_from_gpus(prange, s, l, trigger);
2388 	svm_range_unmap_split(mm, prange, prange, start, last);
2389 
2390 	if (unmap_parent)
2391 		svm_range_add_list_work(svms, prange, mm, SVM_OP_UNMAP_RANGE);
2392 	else
2393 		svm_range_add_list_work(svms, prange, mm,
2394 					SVM_OP_UPDATE_RANGE_NOTIFIER);
2395 	schedule_deferred_list_work(svms);
2396 
2397 	kfd_unref_process(p);
2398 }
2399 
2400 /**
2401  * svm_range_cpu_invalidate_pagetables - interval notifier callback
2402  * @mni: mmu_interval_notifier struct
2403  * @range: mmu_notifier_range struct
2404  * @cur_seq: value to pass to mmu_interval_set_seq()
2405  *
2406  * If event is MMU_NOTIFY_UNMAP, this is from CPU unmap range, otherwise, it
2407  * is from migration, or CPU page invalidation callback.
2408  *
2409  * For unmap event, unmap range from GPUs, remove prange from svms in a delayed
2410  * work thread, and split prange if only part of prange is unmapped.
2411  *
2412  * For invalidation event, if GPU retry fault is not enabled, evict the queues,
2413  * then schedule svm_range_restore_work to update GPU mapping and resume queues.
2414  * If GPU retry fault is enabled, unmap the svm range from GPU, retry fault will
2415  * update GPU mapping to recover.
2416  *
2417  * Context: mmap lock, notifier_invalidate_start lock are held
2418  *          for invalidate event, prange lock is held if this is from migration
2419  */
2420 static bool
2421 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
2422 				    const struct mmu_notifier_range *range,
2423 				    unsigned long cur_seq)
2424 {
2425 	struct svm_range *prange;
2426 	unsigned long start;
2427 	unsigned long last;
2428 
2429 	if (range->event == MMU_NOTIFY_RELEASE)
2430 		return true;
2431 	if (!mmget_not_zero(mni->mm))
2432 		return true;
2433 
2434 	start = mni->interval_tree.start;
2435 	last = mni->interval_tree.last;
2436 	start = max(start, range->start) >> PAGE_SHIFT;
2437 	last = min(last, range->end - 1) >> PAGE_SHIFT;
2438 	pr_debug("[0x%lx 0x%lx] range[0x%lx 0x%lx] notifier[0x%lx 0x%lx] %d\n",
2439 		 start, last, range->start >> PAGE_SHIFT,
2440 		 (range->end - 1) >> PAGE_SHIFT,
2441 		 mni->interval_tree.start >> PAGE_SHIFT,
2442 		 mni->interval_tree.last >> PAGE_SHIFT, range->event);
2443 
2444 	prange = container_of(mni, struct svm_range, notifier);
2445 
2446 	svm_range_lock(prange);
2447 	mmu_interval_set_seq(mni, cur_seq);
2448 
2449 	switch (range->event) {
2450 	case MMU_NOTIFY_UNMAP:
2451 		svm_range_unmap_from_cpu(mni->mm, prange, start, last);
2452 		break;
2453 	default:
2454 		svm_range_evict(prange, mni->mm, start, last, range->event);
2455 		break;
2456 	}
2457 
2458 	svm_range_unlock(prange);
2459 	mmput(mni->mm);
2460 
2461 	return true;
2462 }
2463 
2464 /**
2465  * svm_range_from_addr - find svm range from fault address
2466  * @svms: svm range list header
2467  * @addr: address to search range interval tree, in pages
2468  * @parent: parent range if range is on child list
2469  *
2470  * Context: The caller must hold svms->lock
2471  *
2472  * Return: the svm_range found or NULL
2473  */
2474 struct svm_range *
2475 svm_range_from_addr(struct svm_range_list *svms, unsigned long addr,
2476 		    struct svm_range **parent)
2477 {
2478 	struct interval_tree_node *node;
2479 	struct svm_range *prange;
2480 	struct svm_range *pchild;
2481 
2482 	node = interval_tree_iter_first(&svms->objects, addr, addr);
2483 	if (!node)
2484 		return NULL;
2485 
2486 	prange = container_of(node, struct svm_range, it_node);
2487 	pr_debug("address 0x%lx prange [0x%lx 0x%lx] node [0x%lx 0x%lx]\n",
2488 		 addr, prange->start, prange->last, node->start, node->last);
2489 
2490 	if (addr >= prange->start && addr <= prange->last) {
2491 		if (parent)
2492 			*parent = prange;
2493 		return prange;
2494 	}
2495 	list_for_each_entry(pchild, &prange->child_list, child_list)
2496 		if (addr >= pchild->start && addr <= pchild->last) {
2497 			pr_debug("found address 0x%lx pchild [0x%lx 0x%lx]\n",
2498 				 addr, pchild->start, pchild->last);
2499 			if (parent)
2500 				*parent = prange;
2501 			return pchild;
2502 		}
2503 
2504 	return NULL;
2505 }
2506 
2507 /* svm_range_best_restore_location - decide the best fault restore location
2508  * @prange: svm range structure
2509  * @adev: the GPU on which vm fault happened
2510  *
2511  * This is only called when xnack is on, to decide the best location to restore
2512  * the range mapping after GPU vm fault. Caller uses the best location to do
2513  * migration if actual loc is not best location, then update GPU page table
2514  * mapping to the best location.
2515  *
2516  * If the preferred loc is accessible by faulting GPU, use preferred loc.
2517  * If vm fault gpu idx is on range ACCESSIBLE bitmap, best_loc is vm fault gpu
2518  * If vm fault gpu idx is on range ACCESSIBLE_IN_PLACE bitmap, then
2519  *    if range actual loc is cpu, best_loc is cpu
2520  *    if vm fault gpu is on xgmi same hive of range actual loc gpu, best_loc is
2521  *    range actual loc.
2522  * Otherwise, GPU no access, best_loc is -1.
2523  *
2524  * Return:
2525  * -1 means vm fault GPU no access
2526  * 0 for CPU or GPU id
2527  */
2528 static int32_t
2529 svm_range_best_restore_location(struct svm_range *prange,
2530 				struct kfd_node *node,
2531 				int32_t *gpuidx)
2532 {
2533 	struct kfd_node *bo_node, *preferred_node;
2534 	struct kfd_process *p;
2535 	uint32_t gpuid;
2536 	int r;
2537 
2538 	p = container_of(prange->svms, struct kfd_process, svms);
2539 
2540 	r = kfd_process_gpuid_from_node(p, node, &gpuid, gpuidx);
2541 	if (r < 0) {
2542 		pr_debug("failed to get gpuid from kgd\n");
2543 		return -1;
2544 	}
2545 
2546 	if (prange->preferred_loc == gpuid ||
2547 	    prange->preferred_loc == KFD_IOCTL_SVM_LOCATION_SYSMEM) {
2548 		return prange->preferred_loc;
2549 	} else if (prange->preferred_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
2550 		preferred_node = svm_range_get_node_by_id(prange, prange->preferred_loc);
2551 		if (preferred_node && svm_nodes_in_same_hive(node, preferred_node))
2552 			return prange->preferred_loc;
2553 		/* fall through */
2554 	}
2555 
2556 	if (test_bit(*gpuidx, prange->bitmap_access))
2557 		return gpuid;
2558 
2559 	if (test_bit(*gpuidx, prange->bitmap_aip)) {
2560 		if (!prange->actual_loc)
2561 			return 0;
2562 
2563 		bo_node = svm_range_get_node_by_id(prange, prange->actual_loc);
2564 		if (bo_node && svm_nodes_in_same_hive(node, bo_node))
2565 			return prange->actual_loc;
2566 		else
2567 			return 0;
2568 	}
2569 
2570 	return -1;
2571 }
2572 
2573 static int
2574 svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
2575 			       unsigned long *start, unsigned long *last,
2576 			       bool *is_heap_stack)
2577 {
2578 	struct vm_area_struct *vma;
2579 	struct interval_tree_node *node;
2580 	unsigned long start_limit, end_limit;
2581 
2582 	vma = vma_lookup(p->mm, addr << PAGE_SHIFT);
2583 	if (!vma) {
2584 		pr_debug("VMA does not exist in address [0x%llx]\n", addr);
2585 		return -EFAULT;
2586 	}
2587 
2588 	*is_heap_stack = (vma->vm_start <= vma->vm_mm->brk &&
2589 			  vma->vm_end >= vma->vm_mm->start_brk) ||
2590 			 (vma->vm_start <= vma->vm_mm->start_stack &&
2591 			  vma->vm_end >= vma->vm_mm->start_stack);
2592 
2593 	start_limit = max(vma->vm_start >> PAGE_SHIFT,
2594 		      (unsigned long)ALIGN_DOWN(addr, 2UL << 8));
2595 	end_limit = min(vma->vm_end >> PAGE_SHIFT,
2596 		    (unsigned long)ALIGN(addr + 1, 2UL << 8));
2597 	/* First range that starts after the fault address */
2598 	node = interval_tree_iter_first(&p->svms.objects, addr + 1, ULONG_MAX);
2599 	if (node) {
2600 		end_limit = min(end_limit, node->start);
2601 		/* Last range that ends before the fault address */
2602 		node = container_of(rb_prev(&node->rb),
2603 				    struct interval_tree_node, rb);
2604 	} else {
2605 		/* Last range must end before addr because
2606 		 * there was no range after addr
2607 		 */
2608 		node = container_of(rb_last(&p->svms.objects.rb_root),
2609 				    struct interval_tree_node, rb);
2610 	}
2611 	if (node) {
2612 		if (node->last >= addr) {
2613 			WARN(1, "Overlap with prev node and page fault addr\n");
2614 			return -EFAULT;
2615 		}
2616 		start_limit = max(start_limit, node->last + 1);
2617 	}
2618 
2619 	*start = start_limit;
2620 	*last = end_limit - 1;
2621 
2622 	pr_debug("vma [0x%lx 0x%lx] range [0x%lx 0x%lx] is_heap_stack %d\n",
2623 		 vma->vm_start >> PAGE_SHIFT, vma->vm_end >> PAGE_SHIFT,
2624 		 *start, *last, *is_heap_stack);
2625 
2626 	return 0;
2627 }
2628 
2629 static int
2630 svm_range_check_vm_userptr(struct kfd_process *p, uint64_t start, uint64_t last,
2631 			   uint64_t *bo_s, uint64_t *bo_l)
2632 {
2633 	struct amdgpu_bo_va_mapping *mapping;
2634 	struct interval_tree_node *node;
2635 	struct amdgpu_bo *bo = NULL;
2636 	unsigned long userptr;
2637 	uint32_t i;
2638 	int r;
2639 
2640 	for (i = 0; i < p->n_pdds; i++) {
2641 		struct amdgpu_vm *vm;
2642 
2643 		if (!p->pdds[i]->drm_priv)
2644 			continue;
2645 
2646 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
2647 		r = amdgpu_bo_reserve(vm->root.bo, false);
2648 		if (r)
2649 			return r;
2650 
2651 		/* Check userptr by searching entire vm->va interval tree */
2652 		node = interval_tree_iter_first(&vm->va, 0, ~0ULL);
2653 		while (node) {
2654 			mapping = container_of((struct rb_node *)node,
2655 					       struct amdgpu_bo_va_mapping, rb);
2656 			bo = mapping->bo_va->base.bo;
2657 
2658 			if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm,
2659 							 start << PAGE_SHIFT,
2660 							 last << PAGE_SHIFT,
2661 							 &userptr)) {
2662 				node = interval_tree_iter_next(node, 0, ~0ULL);
2663 				continue;
2664 			}
2665 
2666 			pr_debug("[0x%llx 0x%llx] already userptr mapped\n",
2667 				 start, last);
2668 			if (bo_s && bo_l) {
2669 				*bo_s = userptr >> PAGE_SHIFT;
2670 				*bo_l = *bo_s + bo->tbo.ttm->num_pages - 1;
2671 			}
2672 			amdgpu_bo_unreserve(vm->root.bo);
2673 			return -EADDRINUSE;
2674 		}
2675 		amdgpu_bo_unreserve(vm->root.bo);
2676 	}
2677 	return 0;
2678 }
2679 
2680 static struct
2681 svm_range *svm_range_create_unregistered_range(struct kfd_node *node,
2682 						struct kfd_process *p,
2683 						struct mm_struct *mm,
2684 						int64_t addr)
2685 {
2686 	struct svm_range *prange = NULL;
2687 	unsigned long start, last;
2688 	uint32_t gpuid, gpuidx;
2689 	bool is_heap_stack;
2690 	uint64_t bo_s = 0;
2691 	uint64_t bo_l = 0;
2692 	int r;
2693 
2694 	if (svm_range_get_range_boundaries(p, addr, &start, &last,
2695 					   &is_heap_stack))
2696 		return NULL;
2697 
2698 	r = svm_range_check_vm(p, start, last, &bo_s, &bo_l);
2699 	if (r != -EADDRINUSE)
2700 		r = svm_range_check_vm_userptr(p, start, last, &bo_s, &bo_l);
2701 
2702 	if (r == -EADDRINUSE) {
2703 		if (addr >= bo_s && addr <= bo_l)
2704 			return NULL;
2705 
2706 		/* Create one page svm range if 2MB range overlapping */
2707 		start = addr;
2708 		last = addr;
2709 	}
2710 
2711 	prange = svm_range_new(&p->svms, start, last, true);
2712 	if (!prange) {
2713 		pr_debug("Failed to create prange in address [0x%llx]\n", addr);
2714 		return NULL;
2715 	}
2716 	if (kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx)) {
2717 		pr_debug("failed to get gpuid from kgd\n");
2718 		svm_range_free(prange, true);
2719 		return NULL;
2720 	}
2721 
2722 	if (is_heap_stack)
2723 		prange->preferred_loc = KFD_IOCTL_SVM_LOCATION_SYSMEM;
2724 
2725 	svm_range_add_to_svms(prange);
2726 	svm_range_add_notifier_locked(mm, prange);
2727 
2728 	return prange;
2729 }
2730 
2731 /* svm_range_skip_recover - decide if prange can be recovered
2732  * @prange: svm range structure
2733  *
2734  * GPU vm retry fault handle skip recover the range for cases:
2735  * 1. prange is on deferred list to be removed after unmap, it is stale fault,
2736  *    deferred list work will drain the stale fault before free the prange.
2737  * 2. prange is on deferred list to add interval notifier after split, or
2738  * 3. prange is child range, it is split from parent prange, recover later
2739  *    after interval notifier is added.
2740  *
2741  * Return: true to skip recover, false to recover
2742  */
2743 static bool svm_range_skip_recover(struct svm_range *prange)
2744 {
2745 	struct svm_range_list *svms = prange->svms;
2746 
2747 	spin_lock(&svms->deferred_list_lock);
2748 	if (list_empty(&prange->deferred_list) &&
2749 	    list_empty(&prange->child_list)) {
2750 		spin_unlock(&svms->deferred_list_lock);
2751 		return false;
2752 	}
2753 	spin_unlock(&svms->deferred_list_lock);
2754 
2755 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2756 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] unmapped\n",
2757 			 svms, prange, prange->start, prange->last);
2758 		return true;
2759 	}
2760 	if (prange->work_item.op == SVM_OP_ADD_RANGE_AND_MAP ||
2761 	    prange->work_item.op == SVM_OP_ADD_RANGE) {
2762 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] not added yet\n",
2763 			 svms, prange, prange->start, prange->last);
2764 		return true;
2765 	}
2766 	return false;
2767 }
2768 
2769 static void
2770 svm_range_count_fault(struct kfd_node *node, struct kfd_process *p,
2771 		      int32_t gpuidx)
2772 {
2773 	struct kfd_process_device *pdd;
2774 
2775 	/* fault is on different page of same range
2776 	 * or fault is skipped to recover later
2777 	 * or fault is on invalid virtual address
2778 	 */
2779 	if (gpuidx == MAX_GPU_INSTANCE) {
2780 		uint32_t gpuid;
2781 		int r;
2782 
2783 		r = kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx);
2784 		if (r < 0)
2785 			return;
2786 	}
2787 
2788 	/* fault is recovered
2789 	 * or fault cannot recover because GPU no access on the range
2790 	 */
2791 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
2792 	if (pdd)
2793 		WRITE_ONCE(pdd->faults, pdd->faults + 1);
2794 }
2795 
2796 static bool
2797 svm_fault_allowed(struct vm_area_struct *vma, bool write_fault)
2798 {
2799 	unsigned long requested = VM_READ;
2800 
2801 	if (write_fault)
2802 		requested |= VM_WRITE;
2803 
2804 	pr_debug("requested 0x%lx, vma permission flags 0x%lx\n", requested,
2805 		vma->vm_flags);
2806 	return (vma->vm_flags & requested) == requested;
2807 }
2808 
2809 int
2810 svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
2811 			uint32_t vmid, uint32_t node_id,
2812 			uint64_t addr, bool write_fault)
2813 {
2814 	struct mm_struct *mm = NULL;
2815 	struct svm_range_list *svms;
2816 	struct svm_range *prange;
2817 	struct kfd_process *p;
2818 	ktime_t timestamp = ktime_get_boottime();
2819 	struct kfd_node *node;
2820 	int32_t best_loc;
2821 	int32_t gpuidx = MAX_GPU_INSTANCE;
2822 	bool write_locked = false;
2823 	struct vm_area_struct *vma;
2824 	bool migration = false;
2825 	int r = 0;
2826 
2827 	if (!KFD_IS_SVM_API_SUPPORTED(adev->kfd.dev)) {
2828 		pr_debug("device does not support SVM\n");
2829 		return -EFAULT;
2830 	}
2831 
2832 	p = kfd_lookup_process_by_pasid(pasid);
2833 	if (!p) {
2834 		pr_debug("kfd process not founded pasid 0x%x\n", pasid);
2835 		return 0;
2836 	}
2837 	svms = &p->svms;
2838 
2839 	pr_debug("restoring svms 0x%p fault address 0x%llx\n", svms, addr);
2840 
2841 	if (atomic_read(&svms->drain_pagefaults)) {
2842 		pr_debug("draining retry fault, drop fault 0x%llx\n", addr);
2843 		r = 0;
2844 		goto out;
2845 	}
2846 
2847 	if (!p->xnack_enabled) {
2848 		pr_debug("XNACK not enabled for pasid 0x%x\n", pasid);
2849 		r = -EFAULT;
2850 		goto out;
2851 	}
2852 
2853 	/* p->lead_thread is available as kfd_process_wq_release flush the work
2854 	 * before releasing task ref.
2855 	 */
2856 	mm = get_task_mm(p->lead_thread);
2857 	if (!mm) {
2858 		pr_debug("svms 0x%p failed to get mm\n", svms);
2859 		r = 0;
2860 		goto out;
2861 	}
2862 
2863 	node = kfd_node_by_irq_ids(adev, node_id, vmid);
2864 	if (!node) {
2865 		pr_debug("kfd node does not exist node_id: %d, vmid: %d\n", node_id,
2866 			 vmid);
2867 		r = -EFAULT;
2868 		goto out;
2869 	}
2870 	mmap_read_lock(mm);
2871 retry_write_locked:
2872 	mutex_lock(&svms->lock);
2873 	prange = svm_range_from_addr(svms, addr, NULL);
2874 	if (!prange) {
2875 		pr_debug("failed to find prange svms 0x%p address [0x%llx]\n",
2876 			 svms, addr);
2877 		if (!write_locked) {
2878 			/* Need the write lock to create new range with MMU notifier.
2879 			 * Also flush pending deferred work to make sure the interval
2880 			 * tree is up to date before we add a new range
2881 			 */
2882 			mutex_unlock(&svms->lock);
2883 			mmap_read_unlock(mm);
2884 			mmap_write_lock(mm);
2885 			write_locked = true;
2886 			goto retry_write_locked;
2887 		}
2888 		prange = svm_range_create_unregistered_range(node, p, mm, addr);
2889 		if (!prange) {
2890 			pr_debug("failed to create unregistered range svms 0x%p address [0x%llx]\n",
2891 				 svms, addr);
2892 			mmap_write_downgrade(mm);
2893 			r = -EFAULT;
2894 			goto out_unlock_svms;
2895 		}
2896 	}
2897 	if (write_locked)
2898 		mmap_write_downgrade(mm);
2899 
2900 	mutex_lock(&prange->migrate_mutex);
2901 
2902 	if (svm_range_skip_recover(prange)) {
2903 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
2904 		r = 0;
2905 		goto out_unlock_range;
2906 	}
2907 
2908 	/* skip duplicate vm fault on different pages of same range */
2909 	if (ktime_before(timestamp, ktime_add_ns(prange->validate_timestamp,
2910 				AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING))) {
2911 		pr_debug("svms 0x%p [0x%lx %lx] already restored\n",
2912 			 svms, prange->start, prange->last);
2913 		r = 0;
2914 		goto out_unlock_range;
2915 	}
2916 
2917 	/* __do_munmap removed VMA, return success as we are handling stale
2918 	 * retry fault.
2919 	 */
2920 	vma = vma_lookup(mm, addr << PAGE_SHIFT);
2921 	if (!vma) {
2922 		pr_debug("address 0x%llx VMA is removed\n", addr);
2923 		r = 0;
2924 		goto out_unlock_range;
2925 	}
2926 
2927 	if (!svm_fault_allowed(vma, write_fault)) {
2928 		pr_debug("fault addr 0x%llx no %s permission\n", addr,
2929 			write_fault ? "write" : "read");
2930 		r = -EPERM;
2931 		goto out_unlock_range;
2932 	}
2933 
2934 	best_loc = svm_range_best_restore_location(prange, node, &gpuidx);
2935 	if (best_loc == -1) {
2936 		pr_debug("svms %p failed get best restore loc [0x%lx 0x%lx]\n",
2937 			 svms, prange->start, prange->last);
2938 		r = -EACCES;
2939 		goto out_unlock_range;
2940 	}
2941 
2942 	pr_debug("svms %p [0x%lx 0x%lx] best restore 0x%x, actual loc 0x%x\n",
2943 		 svms, prange->start, prange->last, best_loc,
2944 		 prange->actual_loc);
2945 
2946 	kfd_smi_event_page_fault_start(node, p->lead_thread->pid, addr,
2947 				       write_fault, timestamp);
2948 
2949 	if (prange->actual_loc != best_loc) {
2950 		migration = true;
2951 		if (best_loc) {
2952 			r = svm_migrate_to_vram(prange, best_loc, mm,
2953 					KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU);
2954 			if (r) {
2955 				pr_debug("svm_migrate_to_vram failed (%d) at %llx, falling back to system memory\n",
2956 					 r, addr);
2957 				/* Fallback to system memory if migration to
2958 				 * VRAM failed
2959 				 */
2960 				if (prange->actual_loc)
2961 					r = svm_migrate_vram_to_ram(prange, mm,
2962 					   KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU,
2963 					   NULL);
2964 				else
2965 					r = 0;
2966 			}
2967 		} else {
2968 			r = svm_migrate_vram_to_ram(prange, mm,
2969 					KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU,
2970 					NULL);
2971 		}
2972 		if (r) {
2973 			pr_debug("failed %d to migrate svms %p [0x%lx 0x%lx]\n",
2974 				 r, svms, prange->start, prange->last);
2975 			goto out_unlock_range;
2976 		}
2977 	}
2978 
2979 	r = svm_range_validate_and_map(mm, prange, gpuidx, false, false, false);
2980 	if (r)
2981 		pr_debug("failed %d to map svms 0x%p [0x%lx 0x%lx] to gpus\n",
2982 			 r, svms, prange->start, prange->last);
2983 
2984 	kfd_smi_event_page_fault_end(node, p->lead_thread->pid, addr,
2985 				     migration);
2986 
2987 out_unlock_range:
2988 	mutex_unlock(&prange->migrate_mutex);
2989 out_unlock_svms:
2990 	mutex_unlock(&svms->lock);
2991 	mmap_read_unlock(mm);
2992 
2993 	svm_range_count_fault(node, p, gpuidx);
2994 
2995 	mmput(mm);
2996 out:
2997 	kfd_unref_process(p);
2998 
2999 	if (r == -EAGAIN) {
3000 		pr_debug("recover vm fault later\n");
3001 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
3002 		r = 0;
3003 	}
3004 	return r;
3005 }
3006 
3007 int
3008 svm_range_switch_xnack_reserve_mem(struct kfd_process *p, bool xnack_enabled)
3009 {
3010 	struct svm_range *prange, *pchild;
3011 	uint64_t reserved_size = 0;
3012 	uint64_t size;
3013 	int r = 0;
3014 
3015 	pr_debug("switching xnack from %d to %d\n", p->xnack_enabled, xnack_enabled);
3016 
3017 	mutex_lock(&p->svms.lock);
3018 
3019 	list_for_each_entry(prange, &p->svms.list, list) {
3020 		svm_range_lock(prange);
3021 		list_for_each_entry(pchild, &prange->child_list, child_list) {
3022 			size = (pchild->last - pchild->start + 1) << PAGE_SHIFT;
3023 			if (xnack_enabled) {
3024 				amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3025 						KFD_IOC_ALLOC_MEM_FLAGS_USERPTR);
3026 			} else {
3027 				r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3028 						KFD_IOC_ALLOC_MEM_FLAGS_USERPTR);
3029 				if (r)
3030 					goto out_unlock;
3031 				reserved_size += size;
3032 			}
3033 		}
3034 
3035 		size = (prange->last - prange->start + 1) << PAGE_SHIFT;
3036 		if (xnack_enabled) {
3037 			amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3038 						KFD_IOC_ALLOC_MEM_FLAGS_USERPTR);
3039 		} else {
3040 			r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3041 						KFD_IOC_ALLOC_MEM_FLAGS_USERPTR);
3042 			if (r)
3043 				goto out_unlock;
3044 			reserved_size += size;
3045 		}
3046 out_unlock:
3047 		svm_range_unlock(prange);
3048 		if (r)
3049 			break;
3050 	}
3051 
3052 	if (r)
3053 		amdgpu_amdkfd_unreserve_mem_limit(NULL, reserved_size,
3054 						KFD_IOC_ALLOC_MEM_FLAGS_USERPTR);
3055 	else
3056 		/* Change xnack mode must be inside svms lock, to avoid race with
3057 		 * svm_range_deferred_list_work unreserve memory in parallel.
3058 		 */
3059 		p->xnack_enabled = xnack_enabled;
3060 
3061 	mutex_unlock(&p->svms.lock);
3062 	return r;
3063 }
3064 
3065 void svm_range_list_fini(struct kfd_process *p)
3066 {
3067 	struct svm_range *prange;
3068 	struct svm_range *next;
3069 
3070 	pr_debug("pasid 0x%x svms 0x%p\n", p->pasid, &p->svms);
3071 
3072 	cancel_delayed_work_sync(&p->svms.restore_work);
3073 
3074 	/* Ensure list work is finished before process is destroyed */
3075 	flush_work(&p->svms.deferred_list_work);
3076 
3077 	/*
3078 	 * Ensure no retry fault comes in afterwards, as page fault handler will
3079 	 * not find kfd process and take mm lock to recover fault.
3080 	 */
3081 	atomic_inc(&p->svms.drain_pagefaults);
3082 	svm_range_drain_retry_fault(&p->svms);
3083 
3084 	list_for_each_entry_safe(prange, next, &p->svms.list, list) {
3085 		svm_range_unlink(prange);
3086 		svm_range_remove_notifier(prange);
3087 		svm_range_free(prange, true);
3088 	}
3089 
3090 	mutex_destroy(&p->svms.lock);
3091 
3092 	pr_debug("pasid 0x%x svms 0x%p done\n", p->pasid, &p->svms);
3093 }
3094 
3095 int svm_range_list_init(struct kfd_process *p)
3096 {
3097 	struct svm_range_list *svms = &p->svms;
3098 	int i;
3099 
3100 	svms->objects = RB_ROOT_CACHED;
3101 	mutex_init(&svms->lock);
3102 	INIT_LIST_HEAD(&svms->list);
3103 	atomic_set(&svms->evicted_ranges, 0);
3104 	atomic_set(&svms->drain_pagefaults, 0);
3105 	INIT_DELAYED_WORK(&svms->restore_work, svm_range_restore_work);
3106 	INIT_WORK(&svms->deferred_list_work, svm_range_deferred_list_work);
3107 	INIT_LIST_HEAD(&svms->deferred_range_list);
3108 	INIT_LIST_HEAD(&svms->criu_svm_metadata_list);
3109 	spin_lock_init(&svms->deferred_list_lock);
3110 
3111 	for (i = 0; i < p->n_pdds; i++)
3112 		if (KFD_IS_SVM_API_SUPPORTED(p->pdds[i]->dev->kfd))
3113 			bitmap_set(svms->bitmap_supported, i, 1);
3114 
3115 	return 0;
3116 }
3117 
3118 /**
3119  * svm_range_check_vm - check if virtual address range mapped already
3120  * @p: current kfd_process
3121  * @start: range start address, in pages
3122  * @last: range last address, in pages
3123  * @bo_s: mapping start address in pages if address range already mapped
3124  * @bo_l: mapping last address in pages if address range already mapped
3125  *
3126  * The purpose is to avoid virtual address ranges already allocated by
3127  * kfd_ioctl_alloc_memory_of_gpu ioctl.
3128  * It looks for each pdd in the kfd_process.
3129  *
3130  * Context: Process context
3131  *
3132  * Return 0 - OK, if the range is not mapped.
3133  * Otherwise error code:
3134  * -EADDRINUSE - if address is mapped already by kfd_ioctl_alloc_memory_of_gpu
3135  * -ERESTARTSYS - A wait for the buffer to become unreserved was interrupted by
3136  * a signal. Release all buffer reservations and return to user-space.
3137  */
3138 static int
3139 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
3140 		   uint64_t *bo_s, uint64_t *bo_l)
3141 {
3142 	struct amdgpu_bo_va_mapping *mapping;
3143 	struct interval_tree_node *node;
3144 	uint32_t i;
3145 	int r;
3146 
3147 	for (i = 0; i < p->n_pdds; i++) {
3148 		struct amdgpu_vm *vm;
3149 
3150 		if (!p->pdds[i]->drm_priv)
3151 			continue;
3152 
3153 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
3154 		r = amdgpu_bo_reserve(vm->root.bo, false);
3155 		if (r)
3156 			return r;
3157 
3158 		node = interval_tree_iter_first(&vm->va, start, last);
3159 		if (node) {
3160 			pr_debug("range [0x%llx 0x%llx] already TTM mapped\n",
3161 				 start, last);
3162 			mapping = container_of((struct rb_node *)node,
3163 					       struct amdgpu_bo_va_mapping, rb);
3164 			if (bo_s && bo_l) {
3165 				*bo_s = mapping->start;
3166 				*bo_l = mapping->last;
3167 			}
3168 			amdgpu_bo_unreserve(vm->root.bo);
3169 			return -EADDRINUSE;
3170 		}
3171 		amdgpu_bo_unreserve(vm->root.bo);
3172 	}
3173 
3174 	return 0;
3175 }
3176 
3177 /**
3178  * svm_range_is_valid - check if virtual address range is valid
3179  * @p: current kfd_process
3180  * @start: range start address, in pages
3181  * @size: range size, in pages
3182  *
3183  * Valid virtual address range means it belongs to one or more VMAs
3184  *
3185  * Context: Process context
3186  *
3187  * Return:
3188  *  0 - OK, otherwise error code
3189  */
3190 static int
3191 svm_range_is_valid(struct kfd_process *p, uint64_t start, uint64_t size)
3192 {
3193 	const unsigned long device_vma = VM_IO | VM_PFNMAP | VM_MIXEDMAP;
3194 	struct vm_area_struct *vma;
3195 	unsigned long end;
3196 	unsigned long start_unchg = start;
3197 
3198 	start <<= PAGE_SHIFT;
3199 	end = start + (size << PAGE_SHIFT);
3200 	do {
3201 		vma = vma_lookup(p->mm, start);
3202 		if (!vma || (vma->vm_flags & device_vma))
3203 			return -EFAULT;
3204 		start = min(end, vma->vm_end);
3205 	} while (start < end);
3206 
3207 	return svm_range_check_vm(p, start_unchg, (end - 1) >> PAGE_SHIFT, NULL,
3208 				  NULL);
3209 }
3210 
3211 /**
3212  * svm_range_best_prefetch_location - decide the best prefetch location
3213  * @prange: svm range structure
3214  *
3215  * For xnack off:
3216  * If range map to single GPU, the best prefetch location is prefetch_loc, which
3217  * can be CPU or GPU.
3218  *
3219  * If range is ACCESS or ACCESS_IN_PLACE by mGPUs, only if mGPU connection on
3220  * XGMI same hive, the best prefetch location is prefetch_loc GPU, othervise
3221  * the best prefetch location is always CPU, because GPU can not have coherent
3222  * mapping VRAM of other GPUs even with large-BAR PCIe connection.
3223  *
3224  * For xnack on:
3225  * If range is not ACCESS_IN_PLACE by mGPUs, the best prefetch location is
3226  * prefetch_loc, other GPU access will generate vm fault and trigger migration.
3227  *
3228  * If range is ACCESS_IN_PLACE by mGPUs, only if mGPU connection on XGMI same
3229  * hive, the best prefetch location is prefetch_loc GPU, otherwise the best
3230  * prefetch location is always CPU.
3231  *
3232  * Context: Process context
3233  *
3234  * Return:
3235  * 0 for CPU or GPU id
3236  */
3237 static uint32_t
3238 svm_range_best_prefetch_location(struct svm_range *prange)
3239 {
3240 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
3241 	uint32_t best_loc = prange->prefetch_loc;
3242 	struct kfd_process_device *pdd;
3243 	struct kfd_node *bo_node;
3244 	struct kfd_process *p;
3245 	uint32_t gpuidx;
3246 
3247 	p = container_of(prange->svms, struct kfd_process, svms);
3248 
3249 	if (!best_loc || best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED)
3250 		goto out;
3251 
3252 	bo_node = svm_range_get_node_by_id(prange, best_loc);
3253 	if (!bo_node) {
3254 		WARN_ONCE(1, "failed to get valid kfd node at id%x\n", best_loc);
3255 		best_loc = 0;
3256 		goto out;
3257 	}
3258 
3259 	if (p->xnack_enabled)
3260 		bitmap_copy(bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
3261 	else
3262 		bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
3263 			  MAX_GPU_INSTANCE);
3264 
3265 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
3266 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
3267 		if (!pdd) {
3268 			pr_debug("failed to get device by idx 0x%x\n", gpuidx);
3269 			continue;
3270 		}
3271 
3272 		if (pdd->dev->adev == bo_node->adev)
3273 			continue;
3274 
3275 		if (!svm_nodes_in_same_hive(pdd->dev, bo_node)) {
3276 			best_loc = 0;
3277 			break;
3278 		}
3279 	}
3280 
3281 out:
3282 	pr_debug("xnack %d svms 0x%p [0x%lx 0x%lx] best loc 0x%x\n",
3283 		 p->xnack_enabled, &p->svms, prange->start, prange->last,
3284 		 best_loc);
3285 
3286 	return best_loc;
3287 }
3288 
3289 /* svm_range_trigger_migration - start page migration if prefetch loc changed
3290  * @mm: current process mm_struct
3291  * @prange: svm range structure
3292  * @migrated: output, true if migration is triggered
3293  *
3294  * If range perfetch_loc is GPU, actual loc is cpu 0, then migrate the range
3295  * from ram to vram.
3296  * If range prefetch_loc is cpu 0, actual loc is GPU, then migrate the range
3297  * from vram to ram.
3298  *
3299  * If GPU vm fault retry is not enabled, migration interact with MMU notifier
3300  * and restore work:
3301  * 1. migrate_vma_setup invalidate pages, MMU notifier callback svm_range_evict
3302  *    stops all queues, schedule restore work
3303  * 2. svm_range_restore_work wait for migration is done by
3304  *    a. svm_range_validate_vram takes prange->migrate_mutex
3305  *    b. svm_range_validate_ram HMM get pages wait for CPU fault handle returns
3306  * 3. restore work update mappings of GPU, resume all queues.
3307  *
3308  * Context: Process context
3309  *
3310  * Return:
3311  * 0 - OK, otherwise - error code of migration
3312  */
3313 static int
3314 svm_range_trigger_migration(struct mm_struct *mm, struct svm_range *prange,
3315 			    bool *migrated)
3316 {
3317 	uint32_t best_loc;
3318 	int r = 0;
3319 
3320 	*migrated = false;
3321 	best_loc = svm_range_best_prefetch_location(prange);
3322 
3323 	if (best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3324 	    best_loc == prange->actual_loc)
3325 		return 0;
3326 
3327 	if (!best_loc) {
3328 		r = svm_migrate_vram_to_ram(prange, mm,
3329 					KFD_MIGRATE_TRIGGER_PREFETCH, NULL);
3330 		*migrated = !r;
3331 		return r;
3332 	}
3333 
3334 	r = svm_migrate_to_vram(prange, best_loc, mm, KFD_MIGRATE_TRIGGER_PREFETCH);
3335 	*migrated = !r;
3336 
3337 	return r;
3338 }
3339 
3340 int svm_range_schedule_evict_svm_bo(struct amdgpu_amdkfd_fence *fence)
3341 {
3342 	if (!fence)
3343 		return -EINVAL;
3344 
3345 	if (dma_fence_is_signaled(&fence->base))
3346 		return 0;
3347 
3348 	if (fence->svm_bo) {
3349 		WRITE_ONCE(fence->svm_bo->evicting, 1);
3350 		schedule_work(&fence->svm_bo->eviction_work);
3351 	}
3352 
3353 	return 0;
3354 }
3355 
3356 static void svm_range_evict_svm_bo_worker(struct work_struct *work)
3357 {
3358 	struct svm_range_bo *svm_bo;
3359 	struct mm_struct *mm;
3360 	int r = 0;
3361 
3362 	svm_bo = container_of(work, struct svm_range_bo, eviction_work);
3363 	if (!svm_bo_ref_unless_zero(svm_bo))
3364 		return; /* svm_bo was freed while eviction was pending */
3365 
3366 	if (mmget_not_zero(svm_bo->eviction_fence->mm)) {
3367 		mm = svm_bo->eviction_fence->mm;
3368 	} else {
3369 		svm_range_bo_unref(svm_bo);
3370 		return;
3371 	}
3372 
3373 	mmap_read_lock(mm);
3374 	spin_lock(&svm_bo->list_lock);
3375 	while (!list_empty(&svm_bo->range_list) && !r) {
3376 		struct svm_range *prange =
3377 				list_first_entry(&svm_bo->range_list,
3378 						struct svm_range, svm_bo_list);
3379 		int retries = 3;
3380 
3381 		list_del_init(&prange->svm_bo_list);
3382 		spin_unlock(&svm_bo->list_lock);
3383 
3384 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
3385 			 prange->start, prange->last);
3386 
3387 		mutex_lock(&prange->migrate_mutex);
3388 		do {
3389 			r = svm_migrate_vram_to_ram(prange, mm,
3390 					KFD_MIGRATE_TRIGGER_TTM_EVICTION, NULL);
3391 		} while (!r && prange->actual_loc && --retries);
3392 
3393 		if (!r && prange->actual_loc)
3394 			pr_info_once("Migration failed during eviction");
3395 
3396 		if (!prange->actual_loc) {
3397 			mutex_lock(&prange->lock);
3398 			prange->svm_bo = NULL;
3399 			mutex_unlock(&prange->lock);
3400 		}
3401 		mutex_unlock(&prange->migrate_mutex);
3402 
3403 		spin_lock(&svm_bo->list_lock);
3404 	}
3405 	spin_unlock(&svm_bo->list_lock);
3406 	mmap_read_unlock(mm);
3407 	mmput(mm);
3408 
3409 	dma_fence_signal(&svm_bo->eviction_fence->base);
3410 
3411 	/* This is the last reference to svm_bo, after svm_range_vram_node_free
3412 	 * has been called in svm_migrate_vram_to_ram
3413 	 */
3414 	WARN_ONCE(!r && kref_read(&svm_bo->kref) != 1, "This was not the last reference\n");
3415 	svm_range_bo_unref(svm_bo);
3416 }
3417 
3418 static int
3419 svm_range_set_attr(struct kfd_process *p, struct mm_struct *mm,
3420 		   uint64_t start, uint64_t size, uint32_t nattr,
3421 		   struct kfd_ioctl_svm_attribute *attrs)
3422 {
3423 	struct amdkfd_process_info *process_info = p->kgd_process_info;
3424 	struct list_head update_list;
3425 	struct list_head insert_list;
3426 	struct list_head remove_list;
3427 	struct svm_range_list *svms;
3428 	struct svm_range *prange;
3429 	struct svm_range *next;
3430 	bool update_mapping = false;
3431 	bool flush_tlb;
3432 	int r = 0;
3433 
3434 	pr_debug("pasid 0x%x svms 0x%p [0x%llx 0x%llx] pages 0x%llx\n",
3435 		 p->pasid, &p->svms, start, start + size - 1, size);
3436 
3437 	r = svm_range_check_attr(p, nattr, attrs);
3438 	if (r)
3439 		return r;
3440 
3441 	svms = &p->svms;
3442 
3443 	mutex_lock(&process_info->lock);
3444 
3445 	svm_range_list_lock_and_flush_work(svms, mm);
3446 
3447 	r = svm_range_is_valid(p, start, size);
3448 	if (r) {
3449 		pr_debug("invalid range r=%d\n", r);
3450 		mmap_write_unlock(mm);
3451 		goto out;
3452 	}
3453 
3454 	mutex_lock(&svms->lock);
3455 
3456 	/* Add new range and split existing ranges as needed */
3457 	r = svm_range_add(p, start, size, nattr, attrs, &update_list,
3458 			  &insert_list, &remove_list);
3459 	if (r) {
3460 		mutex_unlock(&svms->lock);
3461 		mmap_write_unlock(mm);
3462 		goto out;
3463 	}
3464 	/* Apply changes as a transaction */
3465 	list_for_each_entry_safe(prange, next, &insert_list, list) {
3466 		svm_range_add_to_svms(prange);
3467 		svm_range_add_notifier_locked(mm, prange);
3468 	}
3469 	list_for_each_entry(prange, &update_list, update_list) {
3470 		svm_range_apply_attrs(p, prange, nattr, attrs, &update_mapping);
3471 		/* TODO: unmap ranges from GPU that lost access */
3472 	}
3473 	list_for_each_entry_safe(prange, next, &remove_list, update_list) {
3474 		pr_debug("unlink old 0x%p prange 0x%p [0x%lx 0x%lx]\n",
3475 			 prange->svms, prange, prange->start,
3476 			 prange->last);
3477 		svm_range_unlink(prange);
3478 		svm_range_remove_notifier(prange);
3479 		svm_range_free(prange, false);
3480 	}
3481 
3482 	mmap_write_downgrade(mm);
3483 	/* Trigger migrations and revalidate and map to GPUs as needed. If
3484 	 * this fails we may be left with partially completed actions. There
3485 	 * is no clean way of rolling back to the previous state in such a
3486 	 * case because the rollback wouldn't be guaranteed to work either.
3487 	 */
3488 	list_for_each_entry(prange, &update_list, update_list) {
3489 		bool migrated;
3490 
3491 		mutex_lock(&prange->migrate_mutex);
3492 
3493 		r = svm_range_trigger_migration(mm, prange, &migrated);
3494 		if (r)
3495 			goto out_unlock_range;
3496 
3497 		if (migrated && (!p->xnack_enabled ||
3498 		    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) &&
3499 		    prange->mapped_to_gpu) {
3500 			pr_debug("restore_work will update mappings of GPUs\n");
3501 			mutex_unlock(&prange->migrate_mutex);
3502 			continue;
3503 		}
3504 
3505 		if (!migrated && !update_mapping) {
3506 			mutex_unlock(&prange->migrate_mutex);
3507 			continue;
3508 		}
3509 
3510 		flush_tlb = !migrated && update_mapping && prange->mapped_to_gpu;
3511 
3512 		r = svm_range_validate_and_map(mm, prange, MAX_GPU_INSTANCE,
3513 					       true, true, flush_tlb);
3514 		if (r)
3515 			pr_debug("failed %d to map svm range\n", r);
3516 
3517 out_unlock_range:
3518 		mutex_unlock(&prange->migrate_mutex);
3519 		if (r)
3520 			break;
3521 	}
3522 
3523 	svm_range_debug_dump(svms);
3524 
3525 	mutex_unlock(&svms->lock);
3526 	mmap_read_unlock(mm);
3527 out:
3528 	mutex_unlock(&process_info->lock);
3529 
3530 	pr_debug("pasid 0x%x svms 0x%p [0x%llx 0x%llx] done, r=%d\n", p->pasid,
3531 		 &p->svms, start, start + size - 1, r);
3532 
3533 	return r;
3534 }
3535 
3536 static int
3537 svm_range_get_attr(struct kfd_process *p, struct mm_struct *mm,
3538 		   uint64_t start, uint64_t size, uint32_t nattr,
3539 		   struct kfd_ioctl_svm_attribute *attrs)
3540 {
3541 	DECLARE_BITMAP(bitmap_access, MAX_GPU_INSTANCE);
3542 	DECLARE_BITMAP(bitmap_aip, MAX_GPU_INSTANCE);
3543 	bool get_preferred_loc = false;
3544 	bool get_prefetch_loc = false;
3545 	bool get_granularity = false;
3546 	bool get_accessible = false;
3547 	bool get_flags = false;
3548 	uint64_t last = start + size - 1UL;
3549 	uint8_t granularity = 0xff;
3550 	struct interval_tree_node *node;
3551 	struct svm_range_list *svms;
3552 	struct svm_range *prange;
3553 	uint32_t prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3554 	uint32_t location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3555 	uint32_t flags_and = 0xffffffff;
3556 	uint32_t flags_or = 0;
3557 	int gpuidx;
3558 	uint32_t i;
3559 	int r = 0;
3560 
3561 	pr_debug("svms 0x%p [0x%llx 0x%llx] nattr 0x%x\n", &p->svms, start,
3562 		 start + size - 1, nattr);
3563 
3564 	/* Flush pending deferred work to avoid racing with deferred actions from
3565 	 * previous memory map changes (e.g. munmap). Concurrent memory map changes
3566 	 * can still race with get_attr because we don't hold the mmap lock. But that
3567 	 * would be a race condition in the application anyway, and undefined
3568 	 * behaviour is acceptable in that case.
3569 	 */
3570 	flush_work(&p->svms.deferred_list_work);
3571 
3572 	mmap_read_lock(mm);
3573 	r = svm_range_is_valid(p, start, size);
3574 	mmap_read_unlock(mm);
3575 	if (r) {
3576 		pr_debug("invalid range r=%d\n", r);
3577 		return r;
3578 	}
3579 
3580 	for (i = 0; i < nattr; i++) {
3581 		switch (attrs[i].type) {
3582 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3583 			get_preferred_loc = true;
3584 			break;
3585 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3586 			get_prefetch_loc = true;
3587 			break;
3588 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3589 			get_accessible = true;
3590 			break;
3591 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3592 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3593 			get_flags = true;
3594 			break;
3595 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3596 			get_granularity = true;
3597 			break;
3598 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
3599 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
3600 			fallthrough;
3601 		default:
3602 			pr_debug("get invalid attr type 0x%x\n", attrs[i].type);
3603 			return -EINVAL;
3604 		}
3605 	}
3606 
3607 	svms = &p->svms;
3608 
3609 	mutex_lock(&svms->lock);
3610 
3611 	node = interval_tree_iter_first(&svms->objects, start, last);
3612 	if (!node) {
3613 		pr_debug("range attrs not found return default values\n");
3614 		svm_range_set_default_attributes(&location, &prefetch_loc,
3615 						 &granularity, &flags_and);
3616 		flags_or = flags_and;
3617 		if (p->xnack_enabled)
3618 			bitmap_copy(bitmap_access, svms->bitmap_supported,
3619 				    MAX_GPU_INSTANCE);
3620 		else
3621 			bitmap_zero(bitmap_access, MAX_GPU_INSTANCE);
3622 		bitmap_zero(bitmap_aip, MAX_GPU_INSTANCE);
3623 		goto fill_values;
3624 	}
3625 	bitmap_copy(bitmap_access, svms->bitmap_supported, MAX_GPU_INSTANCE);
3626 	bitmap_copy(bitmap_aip, svms->bitmap_supported, MAX_GPU_INSTANCE);
3627 
3628 	while (node) {
3629 		struct interval_tree_node *next;
3630 
3631 		prange = container_of(node, struct svm_range, it_node);
3632 		next = interval_tree_iter_next(node, start, last);
3633 
3634 		if (get_preferred_loc) {
3635 			if (prange->preferred_loc ==
3636 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3637 			    (location != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3638 			     location != prange->preferred_loc)) {
3639 				location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3640 				get_preferred_loc = false;
3641 			} else {
3642 				location = prange->preferred_loc;
3643 			}
3644 		}
3645 		if (get_prefetch_loc) {
3646 			if (prange->prefetch_loc ==
3647 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3648 			    (prefetch_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3649 			     prefetch_loc != prange->prefetch_loc)) {
3650 				prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3651 				get_prefetch_loc = false;
3652 			} else {
3653 				prefetch_loc = prange->prefetch_loc;
3654 			}
3655 		}
3656 		if (get_accessible) {
3657 			bitmap_and(bitmap_access, bitmap_access,
3658 				   prange->bitmap_access, MAX_GPU_INSTANCE);
3659 			bitmap_and(bitmap_aip, bitmap_aip,
3660 				   prange->bitmap_aip, MAX_GPU_INSTANCE);
3661 		}
3662 		if (get_flags) {
3663 			flags_and &= prange->flags;
3664 			flags_or |= prange->flags;
3665 		}
3666 
3667 		if (get_granularity && prange->granularity < granularity)
3668 			granularity = prange->granularity;
3669 
3670 		node = next;
3671 	}
3672 fill_values:
3673 	mutex_unlock(&svms->lock);
3674 
3675 	for (i = 0; i < nattr; i++) {
3676 		switch (attrs[i].type) {
3677 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3678 			attrs[i].value = location;
3679 			break;
3680 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3681 			attrs[i].value = prefetch_loc;
3682 			break;
3683 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3684 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
3685 							       attrs[i].value);
3686 			if (gpuidx < 0) {
3687 				pr_debug("invalid gpuid %x\n", attrs[i].value);
3688 				return -EINVAL;
3689 			}
3690 			if (test_bit(gpuidx, bitmap_access))
3691 				attrs[i].type = KFD_IOCTL_SVM_ATTR_ACCESS;
3692 			else if (test_bit(gpuidx, bitmap_aip))
3693 				attrs[i].type =
3694 					KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE;
3695 			else
3696 				attrs[i].type = KFD_IOCTL_SVM_ATTR_NO_ACCESS;
3697 			break;
3698 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3699 			attrs[i].value = flags_and;
3700 			break;
3701 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3702 			attrs[i].value = ~flags_or;
3703 			break;
3704 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3705 			attrs[i].value = (uint32_t)granularity;
3706 			break;
3707 		}
3708 	}
3709 
3710 	return 0;
3711 }
3712 
3713 int kfd_criu_resume_svm(struct kfd_process *p)
3714 {
3715 	struct kfd_ioctl_svm_attribute *set_attr_new, *set_attr = NULL;
3716 	int nattr_common = 4, nattr_accessibility = 1;
3717 	struct criu_svm_metadata *criu_svm_md = NULL;
3718 	struct svm_range_list *svms = &p->svms;
3719 	struct criu_svm_metadata *next = NULL;
3720 	uint32_t set_flags = 0xffffffff;
3721 	int i, j, num_attrs, ret = 0;
3722 	uint64_t set_attr_size;
3723 	struct mm_struct *mm;
3724 
3725 	if (list_empty(&svms->criu_svm_metadata_list)) {
3726 		pr_debug("No SVM data from CRIU restore stage 2\n");
3727 		return ret;
3728 	}
3729 
3730 	mm = get_task_mm(p->lead_thread);
3731 	if (!mm) {
3732 		pr_err("failed to get mm for the target process\n");
3733 		return -ESRCH;
3734 	}
3735 
3736 	num_attrs = nattr_common + (nattr_accessibility * p->n_pdds);
3737 
3738 	i = j = 0;
3739 	list_for_each_entry(criu_svm_md, &svms->criu_svm_metadata_list, list) {
3740 		pr_debug("criu_svm_md[%d]\n\tstart: 0x%llx size: 0x%llx (npages)\n",
3741 			 i, criu_svm_md->data.start_addr, criu_svm_md->data.size);
3742 
3743 		for (j = 0; j < num_attrs; j++) {
3744 			pr_debug("\ncriu_svm_md[%d]->attrs[%d].type : 0x%x\ncriu_svm_md[%d]->attrs[%d].value : 0x%x\n",
3745 				 i, j, criu_svm_md->data.attrs[j].type,
3746 				 i, j, criu_svm_md->data.attrs[j].value);
3747 			switch (criu_svm_md->data.attrs[j].type) {
3748 			/* During Checkpoint operation, the query for
3749 			 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC attribute might
3750 			 * return KFD_IOCTL_SVM_LOCATION_UNDEFINED if they were
3751 			 * not used by the range which was checkpointed. Care
3752 			 * must be taken to not restore with an invalid value
3753 			 * otherwise the gpuidx value will be invalid and
3754 			 * set_attr would eventually fail so just replace those
3755 			 * with another dummy attribute such as
3756 			 * KFD_IOCTL_SVM_ATTR_SET_FLAGS.
3757 			 */
3758 			case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3759 				if (criu_svm_md->data.attrs[j].value ==
3760 				    KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
3761 					criu_svm_md->data.attrs[j].type =
3762 						KFD_IOCTL_SVM_ATTR_SET_FLAGS;
3763 					criu_svm_md->data.attrs[j].value = 0;
3764 				}
3765 				break;
3766 			case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3767 				set_flags = criu_svm_md->data.attrs[j].value;
3768 				break;
3769 			default:
3770 				break;
3771 			}
3772 		}
3773 
3774 		/* CLR_FLAGS is not available via get_attr during checkpoint but
3775 		 * it needs to be inserted before restoring the ranges so
3776 		 * allocate extra space for it before calling set_attr
3777 		 */
3778 		set_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
3779 						(num_attrs + 1);
3780 		set_attr_new = krealloc(set_attr, set_attr_size,
3781 					    GFP_KERNEL);
3782 		if (!set_attr_new) {
3783 			ret = -ENOMEM;
3784 			goto exit;
3785 		}
3786 		set_attr = set_attr_new;
3787 
3788 		memcpy(set_attr, criu_svm_md->data.attrs, num_attrs *
3789 					sizeof(struct kfd_ioctl_svm_attribute));
3790 		set_attr[num_attrs].type = KFD_IOCTL_SVM_ATTR_CLR_FLAGS;
3791 		set_attr[num_attrs].value = ~set_flags;
3792 
3793 		ret = svm_range_set_attr(p, mm, criu_svm_md->data.start_addr,
3794 					 criu_svm_md->data.size, num_attrs + 1,
3795 					 set_attr);
3796 		if (ret) {
3797 			pr_err("CRIU: failed to set range attributes\n");
3798 			goto exit;
3799 		}
3800 
3801 		i++;
3802 	}
3803 exit:
3804 	kfree(set_attr);
3805 	list_for_each_entry_safe(criu_svm_md, next, &svms->criu_svm_metadata_list, list) {
3806 		pr_debug("freeing criu_svm_md[]\n\tstart: 0x%llx\n",
3807 						criu_svm_md->data.start_addr);
3808 		kfree(criu_svm_md);
3809 	}
3810 
3811 	mmput(mm);
3812 	return ret;
3813 
3814 }
3815 
3816 int kfd_criu_restore_svm(struct kfd_process *p,
3817 			 uint8_t __user *user_priv_ptr,
3818 			 uint64_t *priv_data_offset,
3819 			 uint64_t max_priv_data_size)
3820 {
3821 	uint64_t svm_priv_data_size, svm_object_md_size, svm_attrs_size;
3822 	int nattr_common = 4, nattr_accessibility = 1;
3823 	struct criu_svm_metadata *criu_svm_md = NULL;
3824 	struct svm_range_list *svms = &p->svms;
3825 	uint32_t num_devices;
3826 	int ret = 0;
3827 
3828 	num_devices = p->n_pdds;
3829 	/* Handle one SVM range object at a time, also the number of gpus are
3830 	 * assumed to be same on the restore node, checking must be done while
3831 	 * evaluating the topology earlier
3832 	 */
3833 
3834 	svm_attrs_size = sizeof(struct kfd_ioctl_svm_attribute) *
3835 		(nattr_common + nattr_accessibility * num_devices);
3836 	svm_object_md_size = sizeof(struct criu_svm_metadata) + svm_attrs_size;
3837 
3838 	svm_priv_data_size = sizeof(struct kfd_criu_svm_range_priv_data) +
3839 								svm_attrs_size;
3840 
3841 	criu_svm_md = kzalloc(svm_object_md_size, GFP_KERNEL);
3842 	if (!criu_svm_md) {
3843 		pr_err("failed to allocate memory to store svm metadata\n");
3844 		return -ENOMEM;
3845 	}
3846 	if (*priv_data_offset + svm_priv_data_size > max_priv_data_size) {
3847 		ret = -EINVAL;
3848 		goto exit;
3849 	}
3850 
3851 	ret = copy_from_user(&criu_svm_md->data, user_priv_ptr + *priv_data_offset,
3852 			     svm_priv_data_size);
3853 	if (ret) {
3854 		ret = -EFAULT;
3855 		goto exit;
3856 	}
3857 	*priv_data_offset += svm_priv_data_size;
3858 
3859 	list_add_tail(&criu_svm_md->list, &svms->criu_svm_metadata_list);
3860 
3861 	return 0;
3862 
3863 
3864 exit:
3865 	kfree(criu_svm_md);
3866 	return ret;
3867 }
3868 
3869 int svm_range_get_info(struct kfd_process *p, uint32_t *num_svm_ranges,
3870 		       uint64_t *svm_priv_data_size)
3871 {
3872 	uint64_t total_size, accessibility_size, common_attr_size;
3873 	int nattr_common = 4, nattr_accessibility = 1;
3874 	int num_devices = p->n_pdds;
3875 	struct svm_range_list *svms;
3876 	struct svm_range *prange;
3877 	uint32_t count = 0;
3878 
3879 	*svm_priv_data_size = 0;
3880 
3881 	svms = &p->svms;
3882 	if (!svms)
3883 		return -EINVAL;
3884 
3885 	mutex_lock(&svms->lock);
3886 	list_for_each_entry(prange, &svms->list, list) {
3887 		pr_debug("prange: 0x%p start: 0x%lx\t npages: 0x%llx\t end: 0x%llx\n",
3888 			 prange, prange->start, prange->npages,
3889 			 prange->start + prange->npages - 1);
3890 		count++;
3891 	}
3892 	mutex_unlock(&svms->lock);
3893 
3894 	*num_svm_ranges = count;
3895 	/* Only the accessbility attributes need to be queried for all the gpus
3896 	 * individually, remaining ones are spanned across the entire process
3897 	 * regardless of the various gpu nodes. Of the remaining attributes,
3898 	 * KFD_IOCTL_SVM_ATTR_CLR_FLAGS need not be saved.
3899 	 *
3900 	 * KFD_IOCTL_SVM_ATTR_PREFERRED_LOC
3901 	 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC
3902 	 * KFD_IOCTL_SVM_ATTR_SET_FLAGS
3903 	 * KFD_IOCTL_SVM_ATTR_GRANULARITY
3904 	 *
3905 	 * ** ACCESSBILITY ATTRIBUTES **
3906 	 * (Considered as one, type is altered during query, value is gpuid)
3907 	 * KFD_IOCTL_SVM_ATTR_ACCESS
3908 	 * KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE
3909 	 * KFD_IOCTL_SVM_ATTR_NO_ACCESS
3910 	 */
3911 	if (*num_svm_ranges > 0) {
3912 		common_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
3913 			nattr_common;
3914 		accessibility_size = sizeof(struct kfd_ioctl_svm_attribute) *
3915 			nattr_accessibility * num_devices;
3916 
3917 		total_size = sizeof(struct kfd_criu_svm_range_priv_data) +
3918 			common_attr_size + accessibility_size;
3919 
3920 		*svm_priv_data_size = *num_svm_ranges * total_size;
3921 	}
3922 
3923 	pr_debug("num_svm_ranges %u total_priv_size %llu\n", *num_svm_ranges,
3924 		 *svm_priv_data_size);
3925 	return 0;
3926 }
3927 
3928 int kfd_criu_checkpoint_svm(struct kfd_process *p,
3929 			    uint8_t __user *user_priv_data,
3930 			    uint64_t *priv_data_offset)
3931 {
3932 	struct kfd_criu_svm_range_priv_data *svm_priv = NULL;
3933 	struct kfd_ioctl_svm_attribute *query_attr = NULL;
3934 	uint64_t svm_priv_data_size, query_attr_size = 0;
3935 	int index, nattr_common = 4, ret = 0;
3936 	struct svm_range_list *svms;
3937 	int num_devices = p->n_pdds;
3938 	struct svm_range *prange;
3939 	struct mm_struct *mm;
3940 
3941 	svms = &p->svms;
3942 	if (!svms)
3943 		return -EINVAL;
3944 
3945 	mm = get_task_mm(p->lead_thread);
3946 	if (!mm) {
3947 		pr_err("failed to get mm for the target process\n");
3948 		return -ESRCH;
3949 	}
3950 
3951 	query_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
3952 				(nattr_common + num_devices);
3953 
3954 	query_attr = kzalloc(query_attr_size, GFP_KERNEL);
3955 	if (!query_attr) {
3956 		ret = -ENOMEM;
3957 		goto exit;
3958 	}
3959 
3960 	query_attr[0].type = KFD_IOCTL_SVM_ATTR_PREFERRED_LOC;
3961 	query_attr[1].type = KFD_IOCTL_SVM_ATTR_PREFETCH_LOC;
3962 	query_attr[2].type = KFD_IOCTL_SVM_ATTR_SET_FLAGS;
3963 	query_attr[3].type = KFD_IOCTL_SVM_ATTR_GRANULARITY;
3964 
3965 	for (index = 0; index < num_devices; index++) {
3966 		struct kfd_process_device *pdd = p->pdds[index];
3967 
3968 		query_attr[index + nattr_common].type =
3969 			KFD_IOCTL_SVM_ATTR_ACCESS;
3970 		query_attr[index + nattr_common].value = pdd->user_gpu_id;
3971 	}
3972 
3973 	svm_priv_data_size = sizeof(*svm_priv) + query_attr_size;
3974 
3975 	svm_priv = kzalloc(svm_priv_data_size, GFP_KERNEL);
3976 	if (!svm_priv) {
3977 		ret = -ENOMEM;
3978 		goto exit_query;
3979 	}
3980 
3981 	index = 0;
3982 	list_for_each_entry(prange, &svms->list, list) {
3983 
3984 		svm_priv->object_type = KFD_CRIU_OBJECT_TYPE_SVM_RANGE;
3985 		svm_priv->start_addr = prange->start;
3986 		svm_priv->size = prange->npages;
3987 		memcpy(&svm_priv->attrs, query_attr, query_attr_size);
3988 		pr_debug("CRIU: prange: 0x%p start: 0x%lx\t npages: 0x%llx end: 0x%llx\t size: 0x%llx\n",
3989 			 prange, prange->start, prange->npages,
3990 			 prange->start + prange->npages - 1,
3991 			 prange->npages * PAGE_SIZE);
3992 
3993 		ret = svm_range_get_attr(p, mm, svm_priv->start_addr,
3994 					 svm_priv->size,
3995 					 (nattr_common + num_devices),
3996 					 svm_priv->attrs);
3997 		if (ret) {
3998 			pr_err("CRIU: failed to obtain range attributes\n");
3999 			goto exit_priv;
4000 		}
4001 
4002 		if (copy_to_user(user_priv_data + *priv_data_offset, svm_priv,
4003 				 svm_priv_data_size)) {
4004 			pr_err("Failed to copy svm priv to user\n");
4005 			ret = -EFAULT;
4006 			goto exit_priv;
4007 		}
4008 
4009 		*priv_data_offset += svm_priv_data_size;
4010 
4011 	}
4012 
4013 
4014 exit_priv:
4015 	kfree(svm_priv);
4016 exit_query:
4017 	kfree(query_attr);
4018 exit:
4019 	mmput(mm);
4020 	return ret;
4021 }
4022 
4023 int
4024 svm_ioctl(struct kfd_process *p, enum kfd_ioctl_svm_op op, uint64_t start,
4025 	  uint64_t size, uint32_t nattrs, struct kfd_ioctl_svm_attribute *attrs)
4026 {
4027 	struct mm_struct *mm = current->mm;
4028 	int r;
4029 
4030 	start >>= PAGE_SHIFT;
4031 	size >>= PAGE_SHIFT;
4032 
4033 	switch (op) {
4034 	case KFD_IOCTL_SVM_OP_SET_ATTR:
4035 		r = svm_range_set_attr(p, mm, start, size, nattrs, attrs);
4036 		break;
4037 	case KFD_IOCTL_SVM_OP_GET_ATTR:
4038 		r = svm_range_get_attr(p, mm, start, size, nattrs, attrs);
4039 		break;
4040 	default:
4041 		r = EINVAL;
4042 		break;
4043 	}
4044 
4045 	return r;
4046 }
4047