xref: /openbmc/linux/drivers/gpu/drm/amd/amdkfd/kfd_svm.c (revision 078b39c9)
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 <drm/drm_exec.h>
28 
29 #include "amdgpu_sync.h"
30 #include "amdgpu_object.h"
31 #include "amdgpu_vm.h"
32 #include "amdgpu_hmm.h"
33 #include "amdgpu.h"
34 #include "amdgpu_xgmi.h"
35 #include "kfd_priv.h"
36 #include "kfd_svm.h"
37 #include "kfd_migrate.h"
38 #include "kfd_smi_events.h"
39 
40 #ifdef dev_fmt
41 #undef dev_fmt
42 #endif
43 #define dev_fmt(fmt) "kfd_svm: %s: " fmt, __func__
44 
45 #define AMDGPU_SVM_RANGE_RESTORE_DELAY_MS 1
46 
47 /* Long enough to ensure no retry fault comes after svm range is restored and
48  * page table is updated.
49  */
50 #define AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING	(2UL * NSEC_PER_MSEC)
51 
52 /* Giant svm range split into smaller ranges based on this, it is decided using
53  * minimum of all dGPU/APU 1/32 VRAM size, between 2MB to 1GB and alignment to
54  * power of 2MB.
55  */
56 static uint64_t max_svm_range_pages;
57 
58 struct criu_svm_metadata {
59 	struct list_head list;
60 	struct kfd_criu_svm_range_priv_data data;
61 };
62 
63 static void svm_range_evict_svm_bo_worker(struct work_struct *work);
64 static bool
65 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
66 				    const struct mmu_notifier_range *range,
67 				    unsigned long cur_seq);
68 static int
69 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
70 		   uint64_t *bo_s, uint64_t *bo_l);
71 static const struct mmu_interval_notifier_ops svm_range_mn_ops = {
72 	.invalidate = svm_range_cpu_invalidate_pagetables,
73 };
74 
75 /**
76  * svm_range_unlink - unlink svm_range from lists and interval tree
77  * @prange: svm range structure to be removed
78  *
79  * Remove the svm_range from the svms and svm_bo lists and the svms
80  * interval tree.
81  *
82  * Context: The caller must hold svms->lock
83  */
84 static void svm_range_unlink(struct svm_range *prange)
85 {
86 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
87 		 prange, prange->start, prange->last);
88 
89 	if (prange->svm_bo) {
90 		spin_lock(&prange->svm_bo->list_lock);
91 		list_del(&prange->svm_bo_list);
92 		spin_unlock(&prange->svm_bo->list_lock);
93 	}
94 
95 	list_del(&prange->list);
96 	if (prange->it_node.start != 0 && prange->it_node.last != 0)
97 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
98 }
99 
100 static void
101 svm_range_add_notifier_locked(struct mm_struct *mm, struct svm_range *prange)
102 {
103 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
104 		 prange, prange->start, prange->last);
105 
106 	mmu_interval_notifier_insert_locked(&prange->notifier, mm,
107 				     prange->start << PAGE_SHIFT,
108 				     prange->npages << PAGE_SHIFT,
109 				     &svm_range_mn_ops);
110 }
111 
112 /**
113  * svm_range_add_to_svms - add svm range to svms
114  * @prange: svm range structure to be added
115  *
116  * Add the svm range to svms interval tree and link list
117  *
118  * Context: The caller must hold svms->lock
119  */
120 static void svm_range_add_to_svms(struct svm_range *prange)
121 {
122 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
123 		 prange, prange->start, prange->last);
124 
125 	list_move_tail(&prange->list, &prange->svms->list);
126 	prange->it_node.start = prange->start;
127 	prange->it_node.last = prange->last;
128 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
129 }
130 
131 static void svm_range_remove_notifier(struct svm_range *prange)
132 {
133 	pr_debug("remove notifier svms 0x%p prange 0x%p [0x%lx 0x%lx]\n",
134 		 prange->svms, prange,
135 		 prange->notifier.interval_tree.start >> PAGE_SHIFT,
136 		 prange->notifier.interval_tree.last >> PAGE_SHIFT);
137 
138 	if (prange->notifier.interval_tree.start != 0 &&
139 	    prange->notifier.interval_tree.last != 0)
140 		mmu_interval_notifier_remove(&prange->notifier);
141 }
142 
143 static bool
144 svm_is_valid_dma_mapping_addr(struct device *dev, dma_addr_t dma_addr)
145 {
146 	return dma_addr && !dma_mapping_error(dev, dma_addr) &&
147 	       !(dma_addr & SVM_RANGE_VRAM_DOMAIN);
148 }
149 
150 static int
151 svm_range_dma_map_dev(struct amdgpu_device *adev, struct svm_range *prange,
152 		      unsigned long offset, unsigned long npages,
153 		      unsigned long *hmm_pfns, uint32_t gpuidx)
154 {
155 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
156 	dma_addr_t *addr = prange->dma_addr[gpuidx];
157 	struct device *dev = adev->dev;
158 	struct page *page;
159 	int i, r;
160 
161 	if (!addr) {
162 		addr = kvcalloc(prange->npages, sizeof(*addr), GFP_KERNEL);
163 		if (!addr)
164 			return -ENOMEM;
165 		prange->dma_addr[gpuidx] = addr;
166 	}
167 
168 	addr += offset;
169 	for (i = 0; i < npages; i++) {
170 		if (svm_is_valid_dma_mapping_addr(dev, addr[i]))
171 			dma_unmap_page(dev, addr[i], PAGE_SIZE, dir);
172 
173 		page = hmm_pfn_to_page(hmm_pfns[i]);
174 		if (is_zone_device_page(page)) {
175 			struct amdgpu_device *bo_adev = prange->svm_bo->node->adev;
176 
177 			addr[i] = (hmm_pfns[i] << PAGE_SHIFT) +
178 				   bo_adev->vm_manager.vram_base_offset -
179 				   bo_adev->kfd.pgmap.range.start;
180 			addr[i] |= SVM_RANGE_VRAM_DOMAIN;
181 			pr_debug_ratelimited("vram address: 0x%llx\n", addr[i]);
182 			continue;
183 		}
184 		addr[i] = dma_map_page(dev, page, 0, PAGE_SIZE, dir);
185 		r = dma_mapping_error(dev, addr[i]);
186 		if (r) {
187 			dev_err(dev, "failed %d dma_map_page\n", r);
188 			return r;
189 		}
190 		pr_debug_ratelimited("dma mapping 0x%llx for page addr 0x%lx\n",
191 				     addr[i] >> PAGE_SHIFT, page_to_pfn(page));
192 	}
193 	return 0;
194 }
195 
196 static int
197 svm_range_dma_map(struct svm_range *prange, unsigned long *bitmap,
198 		  unsigned long offset, unsigned long npages,
199 		  unsigned long *hmm_pfns)
200 {
201 	struct kfd_process *p;
202 	uint32_t gpuidx;
203 	int r;
204 
205 	p = container_of(prange->svms, struct kfd_process, svms);
206 
207 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
208 		struct kfd_process_device *pdd;
209 
210 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
211 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
212 		if (!pdd) {
213 			pr_debug("failed to find device idx %d\n", gpuidx);
214 			return -EINVAL;
215 		}
216 
217 		r = svm_range_dma_map_dev(pdd->dev->adev, prange, offset, npages,
218 					  hmm_pfns, gpuidx);
219 		if (r)
220 			break;
221 	}
222 
223 	return r;
224 }
225 
226 void svm_range_dma_unmap(struct device *dev, dma_addr_t *dma_addr,
227 			 unsigned long offset, unsigned long npages)
228 {
229 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
230 	int i;
231 
232 	if (!dma_addr)
233 		return;
234 
235 	for (i = offset; i < offset + npages; i++) {
236 		if (!svm_is_valid_dma_mapping_addr(dev, dma_addr[i]))
237 			continue;
238 		pr_debug_ratelimited("unmap 0x%llx\n", dma_addr[i] >> PAGE_SHIFT);
239 		dma_unmap_page(dev, dma_addr[i], PAGE_SIZE, dir);
240 		dma_addr[i] = 0;
241 	}
242 }
243 
244 void svm_range_free_dma_mappings(struct svm_range *prange)
245 {
246 	struct kfd_process_device *pdd;
247 	dma_addr_t *dma_addr;
248 	struct device *dev;
249 	struct kfd_process *p;
250 	uint32_t gpuidx;
251 
252 	p = container_of(prange->svms, struct kfd_process, svms);
253 
254 	for (gpuidx = 0; gpuidx < MAX_GPU_INSTANCE; gpuidx++) {
255 		dma_addr = prange->dma_addr[gpuidx];
256 		if (!dma_addr)
257 			continue;
258 
259 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
260 		if (!pdd) {
261 			pr_debug("failed to find device idx %d\n", gpuidx);
262 			continue;
263 		}
264 		dev = &pdd->dev->adev->pdev->dev;
265 		svm_range_dma_unmap(dev, dma_addr, 0, prange->npages);
266 		kvfree(dma_addr);
267 		prange->dma_addr[gpuidx] = NULL;
268 	}
269 }
270 
271 static void svm_range_free(struct svm_range *prange, bool update_mem_usage)
272 {
273 	uint64_t size = (prange->last - prange->start + 1) << PAGE_SHIFT;
274 	struct kfd_process *p = container_of(prange->svms, struct kfd_process, svms);
275 
276 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms, prange,
277 		 prange->start, prange->last);
278 
279 	svm_range_vram_node_free(prange);
280 	svm_range_free_dma_mappings(prange);
281 
282 	if (update_mem_usage && !p->xnack_enabled) {
283 		pr_debug("unreserve prange 0x%p size: 0x%llx\n", prange, size);
284 		amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
285 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
286 	}
287 	mutex_destroy(&prange->lock);
288 	mutex_destroy(&prange->migrate_mutex);
289 	kfree(prange);
290 }
291 
292 static void
293 svm_range_set_default_attributes(int32_t *location, int32_t *prefetch_loc,
294 				 uint8_t *granularity, uint32_t *flags)
295 {
296 	*location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
297 	*prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
298 	*granularity = 9;
299 	*flags =
300 		KFD_IOCTL_SVM_FLAG_HOST_ACCESS | KFD_IOCTL_SVM_FLAG_COHERENT;
301 }
302 
303 static struct
304 svm_range *svm_range_new(struct svm_range_list *svms, uint64_t start,
305 			 uint64_t last, bool update_mem_usage)
306 {
307 	uint64_t size = last - start + 1;
308 	struct svm_range *prange;
309 	struct kfd_process *p;
310 
311 	prange = kzalloc(sizeof(*prange), GFP_KERNEL);
312 	if (!prange)
313 		return NULL;
314 
315 	p = container_of(svms, struct kfd_process, svms);
316 	if (!p->xnack_enabled && update_mem_usage &&
317 	    amdgpu_amdkfd_reserve_mem_limit(NULL, size << PAGE_SHIFT,
318 				    KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0)) {
319 		pr_info("SVM mapping failed, exceeds resident system memory limit\n");
320 		kfree(prange);
321 		return NULL;
322 	}
323 	prange->npages = size;
324 	prange->svms = svms;
325 	prange->start = start;
326 	prange->last = last;
327 	INIT_LIST_HEAD(&prange->list);
328 	INIT_LIST_HEAD(&prange->update_list);
329 	INIT_LIST_HEAD(&prange->svm_bo_list);
330 	INIT_LIST_HEAD(&prange->deferred_list);
331 	INIT_LIST_HEAD(&prange->child_list);
332 	atomic_set(&prange->invalid, 0);
333 	prange->validate_timestamp = 0;
334 	mutex_init(&prange->migrate_mutex);
335 	mutex_init(&prange->lock);
336 
337 	if (p->xnack_enabled)
338 		bitmap_copy(prange->bitmap_access, svms->bitmap_supported,
339 			    MAX_GPU_INSTANCE);
340 
341 	svm_range_set_default_attributes(&prange->preferred_loc,
342 					 &prange->prefetch_loc,
343 					 &prange->granularity, &prange->flags);
344 
345 	pr_debug("svms 0x%p [0x%llx 0x%llx]\n", svms, start, last);
346 
347 	return prange;
348 }
349 
350 static bool svm_bo_ref_unless_zero(struct svm_range_bo *svm_bo)
351 {
352 	if (!svm_bo || !kref_get_unless_zero(&svm_bo->kref))
353 		return false;
354 
355 	return true;
356 }
357 
358 static void svm_range_bo_release(struct kref *kref)
359 {
360 	struct svm_range_bo *svm_bo;
361 
362 	svm_bo = container_of(kref, struct svm_range_bo, kref);
363 	pr_debug("svm_bo 0x%p\n", svm_bo);
364 
365 	spin_lock(&svm_bo->list_lock);
366 	while (!list_empty(&svm_bo->range_list)) {
367 		struct svm_range *prange =
368 				list_first_entry(&svm_bo->range_list,
369 						struct svm_range, svm_bo_list);
370 		/* list_del_init tells a concurrent svm_range_vram_node_new when
371 		 * it's safe to reuse the svm_bo pointer and svm_bo_list head.
372 		 */
373 		list_del_init(&prange->svm_bo_list);
374 		spin_unlock(&svm_bo->list_lock);
375 
376 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
377 			 prange->start, prange->last);
378 		mutex_lock(&prange->lock);
379 		prange->svm_bo = NULL;
380 		mutex_unlock(&prange->lock);
381 
382 		spin_lock(&svm_bo->list_lock);
383 	}
384 	spin_unlock(&svm_bo->list_lock);
385 	if (!dma_fence_is_signaled(&svm_bo->eviction_fence->base)) {
386 		/* We're not in the eviction worker.
387 		 * Signal the fence and synchronize with any
388 		 * pending eviction work.
389 		 */
390 		dma_fence_signal(&svm_bo->eviction_fence->base);
391 		cancel_work_sync(&svm_bo->eviction_work);
392 	}
393 	dma_fence_put(&svm_bo->eviction_fence->base);
394 	amdgpu_bo_unref(&svm_bo->bo);
395 	kfree(svm_bo);
396 }
397 
398 static void svm_range_bo_wq_release(struct work_struct *work)
399 {
400 	struct svm_range_bo *svm_bo;
401 
402 	svm_bo = container_of(work, struct svm_range_bo, release_work);
403 	svm_range_bo_release(&svm_bo->kref);
404 }
405 
406 static void svm_range_bo_release_async(struct kref *kref)
407 {
408 	struct svm_range_bo *svm_bo;
409 
410 	svm_bo = container_of(kref, struct svm_range_bo, kref);
411 	pr_debug("svm_bo 0x%p\n", svm_bo);
412 	INIT_WORK(&svm_bo->release_work, svm_range_bo_wq_release);
413 	schedule_work(&svm_bo->release_work);
414 }
415 
416 void svm_range_bo_unref_async(struct svm_range_bo *svm_bo)
417 {
418 	kref_put(&svm_bo->kref, svm_range_bo_release_async);
419 }
420 
421 static void svm_range_bo_unref(struct svm_range_bo *svm_bo)
422 {
423 	if (svm_bo)
424 		kref_put(&svm_bo->kref, svm_range_bo_release);
425 }
426 
427 static bool
428 svm_range_validate_svm_bo(struct kfd_node *node, struct svm_range *prange)
429 {
430 	mutex_lock(&prange->lock);
431 	if (!prange->svm_bo) {
432 		mutex_unlock(&prange->lock);
433 		return false;
434 	}
435 	if (prange->ttm_res) {
436 		/* We still have a reference, all is well */
437 		mutex_unlock(&prange->lock);
438 		return true;
439 	}
440 	if (svm_bo_ref_unless_zero(prange->svm_bo)) {
441 		/*
442 		 * Migrate from GPU to GPU, remove range from source svm_bo->node
443 		 * range list, and return false to allocate svm_bo from destination
444 		 * node.
445 		 */
446 		if (prange->svm_bo->node != node) {
447 			mutex_unlock(&prange->lock);
448 
449 			spin_lock(&prange->svm_bo->list_lock);
450 			list_del_init(&prange->svm_bo_list);
451 			spin_unlock(&prange->svm_bo->list_lock);
452 
453 			svm_range_bo_unref(prange->svm_bo);
454 			return false;
455 		}
456 		if (READ_ONCE(prange->svm_bo->evicting)) {
457 			struct dma_fence *f;
458 			struct svm_range_bo *svm_bo;
459 			/* The BO is getting evicted,
460 			 * we need to get a new one
461 			 */
462 			mutex_unlock(&prange->lock);
463 			svm_bo = prange->svm_bo;
464 			f = dma_fence_get(&svm_bo->eviction_fence->base);
465 			svm_range_bo_unref(prange->svm_bo);
466 			/* wait for the fence to avoid long spin-loop
467 			 * at list_empty_careful
468 			 */
469 			dma_fence_wait(f, false);
470 			dma_fence_put(f);
471 		} else {
472 			/* The BO was still around and we got
473 			 * a new reference to it
474 			 */
475 			mutex_unlock(&prange->lock);
476 			pr_debug("reuse old bo svms 0x%p [0x%lx 0x%lx]\n",
477 				 prange->svms, prange->start, prange->last);
478 
479 			prange->ttm_res = prange->svm_bo->bo->tbo.resource;
480 			return true;
481 		}
482 
483 	} else {
484 		mutex_unlock(&prange->lock);
485 	}
486 
487 	/* We need a new svm_bo. Spin-loop to wait for concurrent
488 	 * svm_range_bo_release to finish removing this range from
489 	 * its range list. After this, it is safe to reuse the
490 	 * svm_bo pointer and svm_bo_list head.
491 	 */
492 	while (!list_empty_careful(&prange->svm_bo_list))
493 		;
494 
495 	return false;
496 }
497 
498 static struct svm_range_bo *svm_range_bo_new(void)
499 {
500 	struct svm_range_bo *svm_bo;
501 
502 	svm_bo = kzalloc(sizeof(*svm_bo), GFP_KERNEL);
503 	if (!svm_bo)
504 		return NULL;
505 
506 	kref_init(&svm_bo->kref);
507 	INIT_LIST_HEAD(&svm_bo->range_list);
508 	spin_lock_init(&svm_bo->list_lock);
509 
510 	return svm_bo;
511 }
512 
513 int
514 svm_range_vram_node_new(struct kfd_node *node, struct svm_range *prange,
515 			bool clear)
516 {
517 	struct amdgpu_bo_param bp;
518 	struct svm_range_bo *svm_bo;
519 	struct amdgpu_bo_user *ubo;
520 	struct amdgpu_bo *bo;
521 	struct kfd_process *p;
522 	struct mm_struct *mm;
523 	int r;
524 
525 	p = container_of(prange->svms, struct kfd_process, svms);
526 	pr_debug("pasid: %x svms 0x%p [0x%lx 0x%lx]\n", p->pasid, prange->svms,
527 		 prange->start, prange->last);
528 
529 	if (svm_range_validate_svm_bo(node, prange))
530 		return 0;
531 
532 	svm_bo = svm_range_bo_new();
533 	if (!svm_bo) {
534 		pr_debug("failed to alloc svm bo\n");
535 		return -ENOMEM;
536 	}
537 	mm = get_task_mm(p->lead_thread);
538 	if (!mm) {
539 		pr_debug("failed to get mm\n");
540 		kfree(svm_bo);
541 		return -ESRCH;
542 	}
543 	svm_bo->node = node;
544 	svm_bo->eviction_fence =
545 		amdgpu_amdkfd_fence_create(dma_fence_context_alloc(1),
546 					   mm,
547 					   svm_bo);
548 	mmput(mm);
549 	INIT_WORK(&svm_bo->eviction_work, svm_range_evict_svm_bo_worker);
550 	svm_bo->evicting = 0;
551 	memset(&bp, 0, sizeof(bp));
552 	bp.size = prange->npages * PAGE_SIZE;
553 	bp.byte_align = PAGE_SIZE;
554 	bp.domain = AMDGPU_GEM_DOMAIN_VRAM;
555 	bp.flags = AMDGPU_GEM_CREATE_NO_CPU_ACCESS;
556 	bp.flags |= clear ? AMDGPU_GEM_CREATE_VRAM_CLEARED : 0;
557 	bp.flags |= AMDGPU_GEM_CREATE_DISCARDABLE;
558 	bp.type = ttm_bo_type_device;
559 	bp.resv = NULL;
560 	if (node->xcp)
561 		bp.xcp_id_plus1 = node->xcp->id + 1;
562 
563 	r = amdgpu_bo_create_user(node->adev, &bp, &ubo);
564 	if (r) {
565 		pr_debug("failed %d to create bo\n", r);
566 		goto create_bo_failed;
567 	}
568 	bo = &ubo->bo;
569 
570 	pr_debug("alloc bo at offset 0x%lx size 0x%lx on partition %d\n",
571 		 bo->tbo.resource->start << PAGE_SHIFT, bp.size,
572 		 bp.xcp_id_plus1 - 1);
573 
574 	r = amdgpu_bo_reserve(bo, true);
575 	if (r) {
576 		pr_debug("failed %d to reserve bo\n", r);
577 		goto reserve_bo_failed;
578 	}
579 
580 	if (clear) {
581 		r = amdgpu_bo_sync_wait(bo, AMDGPU_FENCE_OWNER_KFD, false);
582 		if (r) {
583 			pr_debug("failed %d to sync bo\n", r);
584 			amdgpu_bo_unreserve(bo);
585 			goto reserve_bo_failed;
586 		}
587 	}
588 
589 	r = dma_resv_reserve_fences(bo->tbo.base.resv, 1);
590 	if (r) {
591 		pr_debug("failed %d to reserve bo\n", r);
592 		amdgpu_bo_unreserve(bo);
593 		goto reserve_bo_failed;
594 	}
595 	amdgpu_bo_fence(bo, &svm_bo->eviction_fence->base, true);
596 
597 	amdgpu_bo_unreserve(bo);
598 
599 	svm_bo->bo = bo;
600 	prange->svm_bo = svm_bo;
601 	prange->ttm_res = bo->tbo.resource;
602 	prange->offset = 0;
603 
604 	spin_lock(&svm_bo->list_lock);
605 	list_add(&prange->svm_bo_list, &svm_bo->range_list);
606 	spin_unlock(&svm_bo->list_lock);
607 
608 	return 0;
609 
610 reserve_bo_failed:
611 	amdgpu_bo_unref(&bo);
612 create_bo_failed:
613 	dma_fence_put(&svm_bo->eviction_fence->base);
614 	kfree(svm_bo);
615 	prange->ttm_res = NULL;
616 
617 	return r;
618 }
619 
620 void svm_range_vram_node_free(struct svm_range *prange)
621 {
622 	svm_range_bo_unref(prange->svm_bo);
623 	prange->ttm_res = NULL;
624 }
625 
626 struct kfd_node *
627 svm_range_get_node_by_id(struct svm_range *prange, uint32_t gpu_id)
628 {
629 	struct kfd_process *p;
630 	struct kfd_process_device *pdd;
631 
632 	p = container_of(prange->svms, struct kfd_process, svms);
633 	pdd = kfd_process_device_data_by_id(p, gpu_id);
634 	if (!pdd) {
635 		pr_debug("failed to get kfd process device by id 0x%x\n", gpu_id);
636 		return NULL;
637 	}
638 
639 	return pdd->dev;
640 }
641 
642 struct kfd_process_device *
643 svm_range_get_pdd_by_node(struct svm_range *prange, struct kfd_node *node)
644 {
645 	struct kfd_process *p;
646 
647 	p = container_of(prange->svms, struct kfd_process, svms);
648 
649 	return kfd_get_process_device_data(node, p);
650 }
651 
652 static int svm_range_bo_validate(void *param, struct amdgpu_bo *bo)
653 {
654 	struct ttm_operation_ctx ctx = { false, false };
655 
656 	amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_VRAM);
657 
658 	return ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
659 }
660 
661 static int
662 svm_range_check_attr(struct kfd_process *p,
663 		     uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
664 {
665 	uint32_t i;
666 
667 	for (i = 0; i < nattr; i++) {
668 		uint32_t val = attrs[i].value;
669 		int gpuidx = MAX_GPU_INSTANCE;
670 
671 		switch (attrs[i].type) {
672 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
673 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM &&
674 			    val != KFD_IOCTL_SVM_LOCATION_UNDEFINED)
675 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
676 			break;
677 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
678 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM)
679 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
680 			break;
681 		case KFD_IOCTL_SVM_ATTR_ACCESS:
682 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
683 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
684 			gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
685 			break;
686 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
687 			break;
688 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
689 			break;
690 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
691 			break;
692 		default:
693 			pr_debug("unknown attr type 0x%x\n", attrs[i].type);
694 			return -EINVAL;
695 		}
696 
697 		if (gpuidx < 0) {
698 			pr_debug("no GPU 0x%x found\n", val);
699 			return -EINVAL;
700 		} else if (gpuidx < MAX_GPU_INSTANCE &&
701 			   !test_bit(gpuidx, p->svms.bitmap_supported)) {
702 			pr_debug("GPU 0x%x not supported\n", val);
703 			return -EINVAL;
704 		}
705 	}
706 
707 	return 0;
708 }
709 
710 static void
711 svm_range_apply_attrs(struct kfd_process *p, struct svm_range *prange,
712 		      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
713 		      bool *update_mapping)
714 {
715 	uint32_t i;
716 	int gpuidx;
717 
718 	for (i = 0; i < nattr; i++) {
719 		switch (attrs[i].type) {
720 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
721 			prange->preferred_loc = attrs[i].value;
722 			break;
723 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
724 			prange->prefetch_loc = attrs[i].value;
725 			break;
726 		case KFD_IOCTL_SVM_ATTR_ACCESS:
727 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
728 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
729 			if (!p->xnack_enabled)
730 				*update_mapping = true;
731 
732 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
733 							       attrs[i].value);
734 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
735 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
736 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
737 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
738 				bitmap_set(prange->bitmap_access, gpuidx, 1);
739 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
740 			} else {
741 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
742 				bitmap_set(prange->bitmap_aip, gpuidx, 1);
743 			}
744 			break;
745 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
746 			*update_mapping = true;
747 			prange->flags |= attrs[i].value;
748 			break;
749 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
750 			*update_mapping = true;
751 			prange->flags &= ~attrs[i].value;
752 			break;
753 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
754 			prange->granularity = attrs[i].value;
755 			break;
756 		default:
757 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
758 		}
759 	}
760 }
761 
762 static bool
763 svm_range_is_same_attrs(struct kfd_process *p, struct svm_range *prange,
764 			uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
765 {
766 	uint32_t i;
767 	int gpuidx;
768 
769 	for (i = 0; i < nattr; i++) {
770 		switch (attrs[i].type) {
771 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
772 			if (prange->preferred_loc != attrs[i].value)
773 				return false;
774 			break;
775 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
776 			/* Prefetch should always trigger a migration even
777 			 * if the value of the attribute didn't change.
778 			 */
779 			return false;
780 		case KFD_IOCTL_SVM_ATTR_ACCESS:
781 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
782 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
783 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
784 							       attrs[i].value);
785 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
786 				if (test_bit(gpuidx, prange->bitmap_access) ||
787 				    test_bit(gpuidx, prange->bitmap_aip))
788 					return false;
789 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
790 				if (!test_bit(gpuidx, prange->bitmap_access))
791 					return false;
792 			} else {
793 				if (!test_bit(gpuidx, prange->bitmap_aip))
794 					return false;
795 			}
796 			break;
797 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
798 			if ((prange->flags & attrs[i].value) != attrs[i].value)
799 				return false;
800 			break;
801 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
802 			if ((prange->flags & attrs[i].value) != 0)
803 				return false;
804 			break;
805 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
806 			if (prange->granularity != attrs[i].value)
807 				return false;
808 			break;
809 		default:
810 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
811 		}
812 	}
813 
814 	return !prange->is_error_flag;
815 }
816 
817 /**
818  * svm_range_debug_dump - print all range information from svms
819  * @svms: svm range list header
820  *
821  * debug output svm range start, end, prefetch location from svms
822  * interval tree and link list
823  *
824  * Context: The caller must hold svms->lock
825  */
826 static void svm_range_debug_dump(struct svm_range_list *svms)
827 {
828 	struct interval_tree_node *node;
829 	struct svm_range *prange;
830 
831 	pr_debug("dump svms 0x%p list\n", svms);
832 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
833 
834 	list_for_each_entry(prange, &svms->list, list) {
835 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
836 			 prange, prange->start, prange->npages,
837 			 prange->start + prange->npages - 1,
838 			 prange->actual_loc);
839 	}
840 
841 	pr_debug("dump svms 0x%p interval tree\n", svms);
842 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
843 	node = interval_tree_iter_first(&svms->objects, 0, ~0ULL);
844 	while (node) {
845 		prange = container_of(node, struct svm_range, it_node);
846 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
847 			 prange, prange->start, prange->npages,
848 			 prange->start + prange->npages - 1,
849 			 prange->actual_loc);
850 		node = interval_tree_iter_next(node, 0, ~0ULL);
851 	}
852 }
853 
854 static int
855 svm_range_split_array(void *ppnew, void *ppold, size_t size,
856 		      uint64_t old_start, uint64_t old_n,
857 		      uint64_t new_start, uint64_t new_n)
858 {
859 	unsigned char *new, *old, *pold;
860 	uint64_t d;
861 
862 	if (!ppold)
863 		return 0;
864 	pold = *(unsigned char **)ppold;
865 	if (!pold)
866 		return 0;
867 
868 	new = kvmalloc_array(new_n, size, GFP_KERNEL);
869 	if (!new)
870 		return -ENOMEM;
871 
872 	d = (new_start - old_start) * size;
873 	memcpy(new, pold + d, new_n * size);
874 
875 	old = kvmalloc_array(old_n, size, GFP_KERNEL);
876 	if (!old) {
877 		kvfree(new);
878 		return -ENOMEM;
879 	}
880 
881 	d = (new_start == old_start) ? new_n * size : 0;
882 	memcpy(old, pold + d, old_n * size);
883 
884 	kvfree(pold);
885 	*(void **)ppold = old;
886 	*(void **)ppnew = new;
887 
888 	return 0;
889 }
890 
891 static int
892 svm_range_split_pages(struct svm_range *new, struct svm_range *old,
893 		      uint64_t start, uint64_t last)
894 {
895 	uint64_t npages = last - start + 1;
896 	int i, r;
897 
898 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
899 		r = svm_range_split_array(&new->dma_addr[i], &old->dma_addr[i],
900 					  sizeof(*old->dma_addr[i]), old->start,
901 					  npages, new->start, new->npages);
902 		if (r)
903 			return r;
904 	}
905 
906 	return 0;
907 }
908 
909 static int
910 svm_range_split_nodes(struct svm_range *new, struct svm_range *old,
911 		      uint64_t start, uint64_t last)
912 {
913 	uint64_t npages = last - start + 1;
914 
915 	pr_debug("svms 0x%p new prange 0x%p start 0x%lx [0x%llx 0x%llx]\n",
916 		 new->svms, new, new->start, start, last);
917 
918 	if (new->start == old->start) {
919 		new->offset = old->offset;
920 		old->offset += new->npages;
921 	} else {
922 		new->offset = old->offset + npages;
923 	}
924 
925 	new->svm_bo = svm_range_bo_ref(old->svm_bo);
926 	new->ttm_res = old->ttm_res;
927 
928 	spin_lock(&new->svm_bo->list_lock);
929 	list_add(&new->svm_bo_list, &new->svm_bo->range_list);
930 	spin_unlock(&new->svm_bo->list_lock);
931 
932 	return 0;
933 }
934 
935 /**
936  * svm_range_split_adjust - split range and adjust
937  *
938  * @new: new range
939  * @old: the old range
940  * @start: the old range adjust to start address in pages
941  * @last: the old range adjust to last address in pages
942  *
943  * Copy system memory dma_addr or vram ttm_res in old range to new
944  * range from new_start up to size new->npages, the remaining old range is from
945  * start to last
946  *
947  * Return:
948  * 0 - OK, -ENOMEM - out of memory
949  */
950 static int
951 svm_range_split_adjust(struct svm_range *new, struct svm_range *old,
952 		      uint64_t start, uint64_t last)
953 {
954 	int r;
955 
956 	pr_debug("svms 0x%p new 0x%lx old [0x%lx 0x%lx] => [0x%llx 0x%llx]\n",
957 		 new->svms, new->start, old->start, old->last, start, last);
958 
959 	if (new->start < old->start ||
960 	    new->last > old->last) {
961 		WARN_ONCE(1, "invalid new range start or last\n");
962 		return -EINVAL;
963 	}
964 
965 	r = svm_range_split_pages(new, old, start, last);
966 	if (r)
967 		return r;
968 
969 	if (old->actual_loc && old->ttm_res) {
970 		r = svm_range_split_nodes(new, old, start, last);
971 		if (r)
972 			return r;
973 	}
974 
975 	old->npages = last - start + 1;
976 	old->start = start;
977 	old->last = last;
978 	new->flags = old->flags;
979 	new->preferred_loc = old->preferred_loc;
980 	new->prefetch_loc = old->prefetch_loc;
981 	new->actual_loc = old->actual_loc;
982 	new->granularity = old->granularity;
983 	new->mapped_to_gpu = old->mapped_to_gpu;
984 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
985 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
986 
987 	return 0;
988 }
989 
990 /**
991  * svm_range_split - split a range in 2 ranges
992  *
993  * @prange: the svm range to split
994  * @start: the remaining range start address in pages
995  * @last: the remaining range last address in pages
996  * @new: the result new range generated
997  *
998  * Two cases only:
999  * case 1: if start == prange->start
1000  *         prange ==> prange[start, last]
1001  *         new range [last + 1, prange->last]
1002  *
1003  * case 2: if last == prange->last
1004  *         prange ==> prange[start, last]
1005  *         new range [prange->start, start - 1]
1006  *
1007  * Return:
1008  * 0 - OK, -ENOMEM - out of memory, -EINVAL - invalid start, last
1009  */
1010 static int
1011 svm_range_split(struct svm_range *prange, uint64_t start, uint64_t last,
1012 		struct svm_range **new)
1013 {
1014 	uint64_t old_start = prange->start;
1015 	uint64_t old_last = prange->last;
1016 	struct svm_range_list *svms;
1017 	int r = 0;
1018 
1019 	pr_debug("svms 0x%p [0x%llx 0x%llx] to [0x%llx 0x%llx]\n", prange->svms,
1020 		 old_start, old_last, start, last);
1021 
1022 	if (old_start != start && old_last != last)
1023 		return -EINVAL;
1024 	if (start < old_start || last > old_last)
1025 		return -EINVAL;
1026 
1027 	svms = prange->svms;
1028 	if (old_start == start)
1029 		*new = svm_range_new(svms, last + 1, old_last, false);
1030 	else
1031 		*new = svm_range_new(svms, old_start, start - 1, false);
1032 	if (!*new)
1033 		return -ENOMEM;
1034 
1035 	r = svm_range_split_adjust(*new, prange, start, last);
1036 	if (r) {
1037 		pr_debug("failed %d split [0x%llx 0x%llx] to [0x%llx 0x%llx]\n",
1038 			 r, old_start, old_last, start, last);
1039 		svm_range_free(*new, false);
1040 		*new = NULL;
1041 	}
1042 
1043 	return r;
1044 }
1045 
1046 static int
1047 svm_range_split_tail(struct svm_range *prange,
1048 		     uint64_t new_last, struct list_head *insert_list)
1049 {
1050 	struct svm_range *tail;
1051 	int r = svm_range_split(prange, prange->start, new_last, &tail);
1052 
1053 	if (!r)
1054 		list_add(&tail->list, insert_list);
1055 	return r;
1056 }
1057 
1058 static int
1059 svm_range_split_head(struct svm_range *prange,
1060 		     uint64_t new_start, struct list_head *insert_list)
1061 {
1062 	struct svm_range *head;
1063 	int r = svm_range_split(prange, new_start, prange->last, &head);
1064 
1065 	if (!r)
1066 		list_add(&head->list, insert_list);
1067 	return r;
1068 }
1069 
1070 static void
1071 svm_range_add_child(struct svm_range *prange, struct mm_struct *mm,
1072 		    struct svm_range *pchild, enum svm_work_list_ops op)
1073 {
1074 	pr_debug("add child 0x%p [0x%lx 0x%lx] to prange 0x%p child list %d\n",
1075 		 pchild, pchild->start, pchild->last, prange, op);
1076 
1077 	pchild->work_item.mm = mm;
1078 	pchild->work_item.op = op;
1079 	list_add_tail(&pchild->child_list, &prange->child_list);
1080 }
1081 
1082 /**
1083  * svm_range_split_by_granularity - collect ranges within granularity boundary
1084  *
1085  * @p: the process with svms list
1086  * @mm: mm structure
1087  * @addr: the vm fault address in pages, to split the prange
1088  * @parent: parent range if prange is from child list
1089  * @prange: prange to split
1090  *
1091  * Trims @prange to be a single aligned block of prange->granularity if
1092  * possible. The head and tail are added to the child_list in @parent.
1093  *
1094  * Context: caller must hold mmap_read_lock and prange->lock
1095  *
1096  * Return:
1097  * 0 - OK, otherwise error code
1098  */
1099 int
1100 svm_range_split_by_granularity(struct kfd_process *p, struct mm_struct *mm,
1101 			       unsigned long addr, struct svm_range *parent,
1102 			       struct svm_range *prange)
1103 {
1104 	struct svm_range *head, *tail;
1105 	unsigned long start, last, size;
1106 	int r;
1107 
1108 	/* Align splited range start and size to granularity size, then a single
1109 	 * PTE will be used for whole range, this reduces the number of PTE
1110 	 * updated and the L1 TLB space used for translation.
1111 	 */
1112 	size = 1UL << prange->granularity;
1113 	start = ALIGN_DOWN(addr, size);
1114 	last = ALIGN(addr + 1, size) - 1;
1115 
1116 	pr_debug("svms 0x%p split [0x%lx 0x%lx] to [0x%lx 0x%lx] size 0x%lx\n",
1117 		 prange->svms, prange->start, prange->last, start, last, size);
1118 
1119 	if (start > prange->start) {
1120 		r = svm_range_split(prange, start, prange->last, &head);
1121 		if (r)
1122 			return r;
1123 		svm_range_add_child(parent, mm, head, SVM_OP_ADD_RANGE);
1124 	}
1125 
1126 	if (last < prange->last) {
1127 		r = svm_range_split(prange, prange->start, last, &tail);
1128 		if (r)
1129 			return r;
1130 		svm_range_add_child(parent, mm, tail, SVM_OP_ADD_RANGE);
1131 	}
1132 
1133 	/* xnack on, update mapping on GPUs with ACCESS_IN_PLACE */
1134 	if (p->xnack_enabled && prange->work_item.op == SVM_OP_ADD_RANGE) {
1135 		prange->work_item.op = SVM_OP_ADD_RANGE_AND_MAP;
1136 		pr_debug("change prange 0x%p [0x%lx 0x%lx] op %d\n",
1137 			 prange, prange->start, prange->last,
1138 			 SVM_OP_ADD_RANGE_AND_MAP);
1139 	}
1140 	return 0;
1141 }
1142 static bool
1143 svm_nodes_in_same_hive(struct kfd_node *node_a, struct kfd_node *node_b)
1144 {
1145 	return (node_a->adev == node_b->adev ||
1146 		amdgpu_xgmi_same_hive(node_a->adev, node_b->adev));
1147 }
1148 
1149 static uint64_t
1150 svm_range_get_pte_flags(struct kfd_node *node,
1151 			struct svm_range *prange, int domain)
1152 {
1153 	struct kfd_node *bo_node;
1154 	uint32_t flags = prange->flags;
1155 	uint32_t mapping_flags = 0;
1156 	uint64_t pte_flags;
1157 	bool snoop = (domain != SVM_RANGE_VRAM_DOMAIN);
1158 	bool coherent = flags & KFD_IOCTL_SVM_FLAG_COHERENT;
1159 	bool uncached = false; /*flags & KFD_IOCTL_SVM_FLAG_UNCACHED;*/
1160 	unsigned int mtype_local;
1161 
1162 	if (domain == SVM_RANGE_VRAM_DOMAIN)
1163 		bo_node = prange->svm_bo->node;
1164 
1165 	switch (node->adev->ip_versions[GC_HWIP][0]) {
1166 	case IP_VERSION(9, 4, 1):
1167 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1168 			if (bo_node == node) {
1169 				mapping_flags |= coherent ?
1170 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1171 			} else {
1172 				mapping_flags |= coherent ?
1173 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1174 				if (svm_nodes_in_same_hive(node, bo_node))
1175 					snoop = true;
1176 			}
1177 		} else {
1178 			mapping_flags |= coherent ?
1179 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1180 		}
1181 		break;
1182 	case IP_VERSION(9, 4, 2):
1183 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1184 			if (bo_node == node) {
1185 				mapping_flags |= coherent ?
1186 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1187 				if (node->adev->gmc.xgmi.connected_to_cpu)
1188 					snoop = true;
1189 			} else {
1190 				mapping_flags |= coherent ?
1191 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1192 				if (svm_nodes_in_same_hive(node, bo_node))
1193 					snoop = true;
1194 			}
1195 		} else {
1196 			mapping_flags |= coherent ?
1197 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1198 		}
1199 		break;
1200 	case IP_VERSION(9, 4, 3):
1201 		mtype_local = amdgpu_mtype_local == 1 ? AMDGPU_VM_MTYPE_NC :
1202 			     (amdgpu_mtype_local == 2 ? AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW);
1203 		snoop = true;
1204 		if (uncached) {
1205 			mapping_flags |= AMDGPU_VM_MTYPE_UC;
1206 		} else if (domain == SVM_RANGE_VRAM_DOMAIN) {
1207 			/* local HBM region close to partition */
1208 			if (bo_node->adev == node->adev &&
1209 			    (!bo_node->xcp || !node->xcp || bo_node->xcp->mem_id == node->xcp->mem_id))
1210 				mapping_flags |= mtype_local;
1211 			/* local HBM region far from partition or remote XGMI GPU */
1212 			else if (svm_nodes_in_same_hive(bo_node, node))
1213 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1214 			/* PCIe P2P */
1215 			else
1216 				mapping_flags |= AMDGPU_VM_MTYPE_UC;
1217 		/* system memory accessed by the APU */
1218 		} else if (node->adev->flags & AMD_IS_APU) {
1219 			/* On NUMA systems, locality is determined per-page
1220 			 * in amdgpu_gmc_override_vm_pte_flags
1221 			 */
1222 			if (num_possible_nodes() <= 1)
1223 				mapping_flags |= mtype_local;
1224 			else
1225 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1226 		/* system memory accessed by the dGPU */
1227 		} else {
1228 			mapping_flags |= AMDGPU_VM_MTYPE_UC;
1229 		}
1230 		break;
1231 	default:
1232 		mapping_flags |= coherent ?
1233 			AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1234 	}
1235 
1236 	mapping_flags |= AMDGPU_VM_PAGE_READABLE | AMDGPU_VM_PAGE_WRITEABLE;
1237 
1238 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_RO)
1239 		mapping_flags &= ~AMDGPU_VM_PAGE_WRITEABLE;
1240 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_EXEC)
1241 		mapping_flags |= AMDGPU_VM_PAGE_EXECUTABLE;
1242 
1243 	pte_flags = AMDGPU_PTE_VALID;
1244 	pte_flags |= (domain == SVM_RANGE_VRAM_DOMAIN) ? 0 : AMDGPU_PTE_SYSTEM;
1245 	pte_flags |= snoop ? AMDGPU_PTE_SNOOPED : 0;
1246 
1247 	pte_flags |= amdgpu_gem_va_map_flags(node->adev, mapping_flags);
1248 	return pte_flags;
1249 }
1250 
1251 static int
1252 svm_range_unmap_from_gpu(struct amdgpu_device *adev, struct amdgpu_vm *vm,
1253 			 uint64_t start, uint64_t last,
1254 			 struct dma_fence **fence)
1255 {
1256 	uint64_t init_pte_value = 0;
1257 
1258 	pr_debug("[0x%llx 0x%llx]\n", start, last);
1259 
1260 	return amdgpu_vm_update_range(adev, vm, false, true, true, NULL, start,
1261 				      last, init_pte_value, 0, 0, NULL, NULL,
1262 				      fence);
1263 }
1264 
1265 static int
1266 svm_range_unmap_from_gpus(struct svm_range *prange, unsigned long start,
1267 			  unsigned long last, uint32_t trigger)
1268 {
1269 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1270 	struct kfd_process_device *pdd;
1271 	struct dma_fence *fence = NULL;
1272 	struct kfd_process *p;
1273 	uint32_t gpuidx;
1274 	int r = 0;
1275 
1276 	if (!prange->mapped_to_gpu) {
1277 		pr_debug("prange 0x%p [0x%lx 0x%lx] not mapped to GPU\n",
1278 			 prange, prange->start, prange->last);
1279 		return 0;
1280 	}
1281 
1282 	if (prange->start == start && prange->last == last) {
1283 		pr_debug("unmap svms 0x%p prange 0x%p\n", prange->svms, prange);
1284 		prange->mapped_to_gpu = false;
1285 	}
1286 
1287 	bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
1288 		  MAX_GPU_INSTANCE);
1289 	p = container_of(prange->svms, struct kfd_process, svms);
1290 
1291 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1292 		pr_debug("unmap from gpu idx 0x%x\n", gpuidx);
1293 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1294 		if (!pdd) {
1295 			pr_debug("failed to find device idx %d\n", gpuidx);
1296 			return -EINVAL;
1297 		}
1298 
1299 		kfd_smi_event_unmap_from_gpu(pdd->dev, p->lead_thread->pid,
1300 					     start, last, trigger);
1301 
1302 		r = svm_range_unmap_from_gpu(pdd->dev->adev,
1303 					     drm_priv_to_vm(pdd->drm_priv),
1304 					     start, last, &fence);
1305 		if (r)
1306 			break;
1307 
1308 		if (fence) {
1309 			r = dma_fence_wait(fence, false);
1310 			dma_fence_put(fence);
1311 			fence = NULL;
1312 			if (r)
1313 				break;
1314 		}
1315 		kfd_flush_tlb(pdd, TLB_FLUSH_HEAVYWEIGHT);
1316 	}
1317 
1318 	return r;
1319 }
1320 
1321 static int
1322 svm_range_map_to_gpu(struct kfd_process_device *pdd, struct svm_range *prange,
1323 		     unsigned long offset, unsigned long npages, bool readonly,
1324 		     dma_addr_t *dma_addr, struct amdgpu_device *bo_adev,
1325 		     struct dma_fence **fence, bool flush_tlb)
1326 {
1327 	struct amdgpu_device *adev = pdd->dev->adev;
1328 	struct amdgpu_vm *vm = drm_priv_to_vm(pdd->drm_priv);
1329 	uint64_t pte_flags;
1330 	unsigned long last_start;
1331 	int last_domain;
1332 	int r = 0;
1333 	int64_t i, j;
1334 
1335 	last_start = prange->start + offset;
1336 
1337 	pr_debug("svms 0x%p [0x%lx 0x%lx] readonly %d\n", prange->svms,
1338 		 last_start, last_start + npages - 1, readonly);
1339 
1340 	for (i = offset; i < offset + npages; i++) {
1341 		last_domain = dma_addr[i] & SVM_RANGE_VRAM_DOMAIN;
1342 		dma_addr[i] &= ~SVM_RANGE_VRAM_DOMAIN;
1343 
1344 		/* Collect all pages in the same address range and memory domain
1345 		 * that can be mapped with a single call to update mapping.
1346 		 */
1347 		if (i < offset + npages - 1 &&
1348 		    last_domain == (dma_addr[i + 1] & SVM_RANGE_VRAM_DOMAIN))
1349 			continue;
1350 
1351 		pr_debug("Mapping range [0x%lx 0x%llx] on domain: %s\n",
1352 			 last_start, prange->start + i, last_domain ? "GPU" : "CPU");
1353 
1354 		pte_flags = svm_range_get_pte_flags(pdd->dev, prange, last_domain);
1355 		if (readonly)
1356 			pte_flags &= ~AMDGPU_PTE_WRITEABLE;
1357 
1358 		pr_debug("svms 0x%p map [0x%lx 0x%llx] vram %d PTE 0x%llx\n",
1359 			 prange->svms, last_start, prange->start + i,
1360 			 (last_domain == SVM_RANGE_VRAM_DOMAIN) ? 1 : 0,
1361 			 pte_flags);
1362 
1363 		/* For dGPU mode, we use same vm_manager to allocate VRAM for
1364 		 * different memory partition based on fpfn/lpfn, we should use
1365 		 * same vm_manager.vram_base_offset regardless memory partition.
1366 		 */
1367 		r = amdgpu_vm_update_range(adev, vm, false, false, flush_tlb, NULL,
1368 					   last_start, prange->start + i,
1369 					   pte_flags,
1370 					   (last_start - prange->start) << PAGE_SHIFT,
1371 					   bo_adev ? bo_adev->vm_manager.vram_base_offset : 0,
1372 					   NULL, dma_addr, &vm->last_update);
1373 
1374 		for (j = last_start - prange->start; j <= i; j++)
1375 			dma_addr[j] |= last_domain;
1376 
1377 		if (r) {
1378 			pr_debug("failed %d to map to gpu 0x%lx\n", r, prange->start);
1379 			goto out;
1380 		}
1381 		last_start = prange->start + i + 1;
1382 	}
1383 
1384 	r = amdgpu_vm_update_pdes(adev, vm, false);
1385 	if (r) {
1386 		pr_debug("failed %d to update directories 0x%lx\n", r,
1387 			 prange->start);
1388 		goto out;
1389 	}
1390 
1391 	if (fence)
1392 		*fence = dma_fence_get(vm->last_update);
1393 
1394 out:
1395 	return r;
1396 }
1397 
1398 static int
1399 svm_range_map_to_gpus(struct svm_range *prange, unsigned long offset,
1400 		      unsigned long npages, bool readonly,
1401 		      unsigned long *bitmap, bool wait, bool flush_tlb)
1402 {
1403 	struct kfd_process_device *pdd;
1404 	struct amdgpu_device *bo_adev = NULL;
1405 	struct kfd_process *p;
1406 	struct dma_fence *fence = NULL;
1407 	uint32_t gpuidx;
1408 	int r = 0;
1409 
1410 	if (prange->svm_bo && prange->ttm_res)
1411 		bo_adev = prange->svm_bo->node->adev;
1412 
1413 	p = container_of(prange->svms, struct kfd_process, svms);
1414 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1415 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
1416 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1417 		if (!pdd) {
1418 			pr_debug("failed to find device idx %d\n", gpuidx);
1419 			return -EINVAL;
1420 		}
1421 
1422 		pdd = kfd_bind_process_to_device(pdd->dev, p);
1423 		if (IS_ERR(pdd))
1424 			return -EINVAL;
1425 
1426 		if (bo_adev && pdd->dev->adev != bo_adev &&
1427 		    !amdgpu_xgmi_same_hive(pdd->dev->adev, bo_adev)) {
1428 			pr_debug("cannot map to device idx %d\n", gpuidx);
1429 			continue;
1430 		}
1431 
1432 		r = svm_range_map_to_gpu(pdd, prange, offset, npages, readonly,
1433 					 prange->dma_addr[gpuidx],
1434 					 bo_adev, wait ? &fence : NULL,
1435 					 flush_tlb);
1436 		if (r)
1437 			break;
1438 
1439 		if (fence) {
1440 			r = dma_fence_wait(fence, false);
1441 			dma_fence_put(fence);
1442 			fence = NULL;
1443 			if (r) {
1444 				pr_debug("failed %d to dma fence wait\n", r);
1445 				break;
1446 			}
1447 		}
1448 
1449 		kfd_flush_tlb(pdd, TLB_FLUSH_LEGACY);
1450 	}
1451 
1452 	return r;
1453 }
1454 
1455 struct svm_validate_context {
1456 	struct kfd_process *process;
1457 	struct svm_range *prange;
1458 	bool intr;
1459 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1460 	struct drm_exec exec;
1461 };
1462 
1463 static int svm_range_reserve_bos(struct svm_validate_context *ctx, bool intr)
1464 {
1465 	struct kfd_process_device *pdd;
1466 	struct amdgpu_vm *vm;
1467 	uint32_t gpuidx;
1468 	int r;
1469 
1470 	drm_exec_init(&ctx->exec, intr ? DRM_EXEC_INTERRUPTIBLE_WAIT: 0);
1471 	drm_exec_until_all_locked(&ctx->exec) {
1472 		for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1473 			pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1474 			if (!pdd) {
1475 				pr_debug("failed to find device idx %d\n", gpuidx);
1476 				r = -EINVAL;
1477 				goto unreserve_out;
1478 			}
1479 			vm = drm_priv_to_vm(pdd->drm_priv);
1480 
1481 			r = amdgpu_vm_lock_pd(vm, &ctx->exec, 2);
1482 			drm_exec_retry_on_contention(&ctx->exec);
1483 			if (unlikely(r)) {
1484 				pr_debug("failed %d to reserve bo\n", r);
1485 				goto unreserve_out;
1486 			}
1487 		}
1488 	}
1489 
1490 	for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1491 		pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1492 		if (!pdd) {
1493 			pr_debug("failed to find device idx %d\n", gpuidx);
1494 			r = -EINVAL;
1495 			goto unreserve_out;
1496 		}
1497 
1498 		r = amdgpu_vm_validate_pt_bos(pdd->dev->adev,
1499 					      drm_priv_to_vm(pdd->drm_priv),
1500 					      svm_range_bo_validate, NULL);
1501 		if (r) {
1502 			pr_debug("failed %d validate pt bos\n", r);
1503 			goto unreserve_out;
1504 		}
1505 	}
1506 
1507 	return 0;
1508 
1509 unreserve_out:
1510 	drm_exec_fini(&ctx->exec);
1511 	return r;
1512 }
1513 
1514 static void svm_range_unreserve_bos(struct svm_validate_context *ctx)
1515 {
1516 	drm_exec_fini(&ctx->exec);
1517 }
1518 
1519 static void *kfd_svm_page_owner(struct kfd_process *p, int32_t gpuidx)
1520 {
1521 	struct kfd_process_device *pdd;
1522 
1523 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1524 
1525 	return SVM_ADEV_PGMAP_OWNER(pdd->dev->adev);
1526 }
1527 
1528 /*
1529  * Validation+GPU mapping with concurrent invalidation (MMU notifiers)
1530  *
1531  * To prevent concurrent destruction or change of range attributes, the
1532  * svm_read_lock must be held. The caller must not hold the svm_write_lock
1533  * because that would block concurrent evictions and lead to deadlocks. To
1534  * serialize concurrent migrations or validations of the same range, the
1535  * prange->migrate_mutex must be held.
1536  *
1537  * For VRAM ranges, the SVM BO must be allocated and valid (protected by its
1538  * eviction fence.
1539  *
1540  * The following sequence ensures race-free validation and GPU mapping:
1541  *
1542  * 1. Reserve page table (and SVM BO if range is in VRAM)
1543  * 2. hmm_range_fault to get page addresses (if system memory)
1544  * 3. DMA-map pages (if system memory)
1545  * 4-a. Take notifier lock
1546  * 4-b. Check that pages still valid (mmu_interval_read_retry)
1547  * 4-c. Check that the range was not split or otherwise invalidated
1548  * 4-d. Update GPU page table
1549  * 4.e. Release notifier lock
1550  * 5. Release page table (and SVM BO) reservation
1551  */
1552 static int svm_range_validate_and_map(struct mm_struct *mm,
1553 				      struct svm_range *prange, int32_t gpuidx,
1554 				      bool intr, bool wait, bool flush_tlb)
1555 {
1556 	struct svm_validate_context *ctx;
1557 	unsigned long start, end, addr;
1558 	struct kfd_process *p;
1559 	void *owner;
1560 	int32_t idx;
1561 	int r = 0;
1562 
1563 	ctx = kzalloc(sizeof(struct svm_validate_context), GFP_KERNEL);
1564 	if (!ctx)
1565 		return -ENOMEM;
1566 	ctx->process = container_of(prange->svms, struct kfd_process, svms);
1567 	ctx->prange = prange;
1568 	ctx->intr = intr;
1569 
1570 	if (gpuidx < MAX_GPU_INSTANCE) {
1571 		bitmap_zero(ctx->bitmap, MAX_GPU_INSTANCE);
1572 		bitmap_set(ctx->bitmap, gpuidx, 1);
1573 	} else if (ctx->process->xnack_enabled) {
1574 		bitmap_copy(ctx->bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
1575 
1576 		/* If prefetch range to GPU, or GPU retry fault migrate range to
1577 		 * GPU, which has ACCESS attribute to the range, create mapping
1578 		 * on that GPU.
1579 		 */
1580 		if (prange->actual_loc) {
1581 			gpuidx = kfd_process_gpuidx_from_gpuid(ctx->process,
1582 							prange->actual_loc);
1583 			if (gpuidx < 0) {
1584 				WARN_ONCE(1, "failed get device by id 0x%x\n",
1585 					 prange->actual_loc);
1586 				r = -EINVAL;
1587 				goto free_ctx;
1588 			}
1589 			if (test_bit(gpuidx, prange->bitmap_access))
1590 				bitmap_set(ctx->bitmap, gpuidx, 1);
1591 		}
1592 	} else {
1593 		bitmap_or(ctx->bitmap, prange->bitmap_access,
1594 			  prange->bitmap_aip, MAX_GPU_INSTANCE);
1595 	}
1596 
1597 	if (bitmap_empty(ctx->bitmap, MAX_GPU_INSTANCE)) {
1598 		if (!prange->mapped_to_gpu) {
1599 			r = 0;
1600 			goto free_ctx;
1601 		}
1602 
1603 		bitmap_copy(ctx->bitmap, prange->bitmap_access, MAX_GPU_INSTANCE);
1604 	}
1605 
1606 	if (prange->actual_loc && !prange->ttm_res) {
1607 		/* This should never happen. actual_loc gets set by
1608 		 * svm_migrate_ram_to_vram after allocating a BO.
1609 		 */
1610 		WARN_ONCE(1, "VRAM BO missing during validation\n");
1611 		r = -EINVAL;
1612 		goto free_ctx;
1613 	}
1614 
1615 	svm_range_reserve_bos(ctx, intr);
1616 
1617 	p = container_of(prange->svms, struct kfd_process, svms);
1618 	owner = kfd_svm_page_owner(p, find_first_bit(ctx->bitmap,
1619 						MAX_GPU_INSTANCE));
1620 	for_each_set_bit(idx, ctx->bitmap, MAX_GPU_INSTANCE) {
1621 		if (kfd_svm_page_owner(p, idx) != owner) {
1622 			owner = NULL;
1623 			break;
1624 		}
1625 	}
1626 
1627 	start = prange->start << PAGE_SHIFT;
1628 	end = (prange->last + 1) << PAGE_SHIFT;
1629 	for (addr = start; addr < end && !r; ) {
1630 		struct hmm_range *hmm_range;
1631 		struct vm_area_struct *vma;
1632 		unsigned long next;
1633 		unsigned long offset;
1634 		unsigned long npages;
1635 		bool readonly;
1636 
1637 		vma = vma_lookup(mm, addr);
1638 		if (!vma) {
1639 			r = -EFAULT;
1640 			goto unreserve_out;
1641 		}
1642 		readonly = !(vma->vm_flags & VM_WRITE);
1643 
1644 		next = min(vma->vm_end, end);
1645 		npages = (next - addr) >> PAGE_SHIFT;
1646 		WRITE_ONCE(p->svms.faulting_task, current);
1647 		r = amdgpu_hmm_range_get_pages(&prange->notifier, addr, npages,
1648 					       readonly, owner, NULL,
1649 					       &hmm_range);
1650 		WRITE_ONCE(p->svms.faulting_task, NULL);
1651 		if (r) {
1652 			pr_debug("failed %d to get svm range pages\n", r);
1653 			goto unreserve_out;
1654 		}
1655 
1656 		offset = (addr - start) >> PAGE_SHIFT;
1657 		r = svm_range_dma_map(prange, ctx->bitmap, offset, npages,
1658 				      hmm_range->hmm_pfns);
1659 		if (r) {
1660 			pr_debug("failed %d to dma map range\n", r);
1661 			goto unreserve_out;
1662 		}
1663 
1664 		svm_range_lock(prange);
1665 		if (amdgpu_hmm_range_get_pages_done(hmm_range)) {
1666 			pr_debug("hmm update the range, need validate again\n");
1667 			r = -EAGAIN;
1668 			goto unlock_out;
1669 		}
1670 		if (!list_empty(&prange->child_list)) {
1671 			pr_debug("range split by unmap in parallel, validate again\n");
1672 			r = -EAGAIN;
1673 			goto unlock_out;
1674 		}
1675 
1676 		r = svm_range_map_to_gpus(prange, offset, npages, readonly,
1677 					  ctx->bitmap, wait, flush_tlb);
1678 
1679 unlock_out:
1680 		svm_range_unlock(prange);
1681 
1682 		addr = next;
1683 	}
1684 
1685 	if (addr == end) {
1686 		prange->validated_once = true;
1687 		prange->mapped_to_gpu = true;
1688 	}
1689 
1690 unreserve_out:
1691 	svm_range_unreserve_bos(ctx);
1692 
1693 	prange->is_error_flag = !!r;
1694 	if (!r)
1695 		prange->validate_timestamp = ktime_get_boottime();
1696 
1697 free_ctx:
1698 	kfree(ctx);
1699 
1700 	return r;
1701 }
1702 
1703 /**
1704  * svm_range_list_lock_and_flush_work - flush pending deferred work
1705  *
1706  * @svms: the svm range list
1707  * @mm: the mm structure
1708  *
1709  * Context: Returns with mmap write lock held, pending deferred work flushed
1710  *
1711  */
1712 void
1713 svm_range_list_lock_and_flush_work(struct svm_range_list *svms,
1714 				   struct mm_struct *mm)
1715 {
1716 retry_flush_work:
1717 	flush_work(&svms->deferred_list_work);
1718 	mmap_write_lock(mm);
1719 
1720 	if (list_empty(&svms->deferred_range_list))
1721 		return;
1722 	mmap_write_unlock(mm);
1723 	pr_debug("retry flush\n");
1724 	goto retry_flush_work;
1725 }
1726 
1727 static void svm_range_restore_work(struct work_struct *work)
1728 {
1729 	struct delayed_work *dwork = to_delayed_work(work);
1730 	struct amdkfd_process_info *process_info;
1731 	struct svm_range_list *svms;
1732 	struct svm_range *prange;
1733 	struct kfd_process *p;
1734 	struct mm_struct *mm;
1735 	int evicted_ranges;
1736 	int invalid;
1737 	int r;
1738 
1739 	svms = container_of(dwork, struct svm_range_list, restore_work);
1740 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1741 	if (!evicted_ranges)
1742 		return;
1743 
1744 	pr_debug("restore svm ranges\n");
1745 
1746 	p = container_of(svms, struct kfd_process, svms);
1747 	process_info = p->kgd_process_info;
1748 
1749 	/* Keep mm reference when svm_range_validate_and_map ranges */
1750 	mm = get_task_mm(p->lead_thread);
1751 	if (!mm) {
1752 		pr_debug("svms 0x%p process mm gone\n", svms);
1753 		return;
1754 	}
1755 
1756 	mutex_lock(&process_info->lock);
1757 	svm_range_list_lock_and_flush_work(svms, mm);
1758 	mutex_lock(&svms->lock);
1759 
1760 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1761 
1762 	list_for_each_entry(prange, &svms->list, list) {
1763 		invalid = atomic_read(&prange->invalid);
1764 		if (!invalid)
1765 			continue;
1766 
1767 		pr_debug("restoring svms 0x%p prange 0x%p [0x%lx %lx] inv %d\n",
1768 			 prange->svms, prange, prange->start, prange->last,
1769 			 invalid);
1770 
1771 		/*
1772 		 * If range is migrating, wait for migration is done.
1773 		 */
1774 		mutex_lock(&prange->migrate_mutex);
1775 
1776 		r = svm_range_validate_and_map(mm, prange, MAX_GPU_INSTANCE,
1777 					       false, true, false);
1778 		if (r)
1779 			pr_debug("failed %d to map 0x%lx to gpus\n", r,
1780 				 prange->start);
1781 
1782 		mutex_unlock(&prange->migrate_mutex);
1783 		if (r)
1784 			goto out_reschedule;
1785 
1786 		if (atomic_cmpxchg(&prange->invalid, invalid, 0) != invalid)
1787 			goto out_reschedule;
1788 	}
1789 
1790 	if (atomic_cmpxchg(&svms->evicted_ranges, evicted_ranges, 0) !=
1791 	    evicted_ranges)
1792 		goto out_reschedule;
1793 
1794 	evicted_ranges = 0;
1795 
1796 	r = kgd2kfd_resume_mm(mm);
1797 	if (r) {
1798 		/* No recovery from this failure. Probably the CP is
1799 		 * hanging. No point trying again.
1800 		 */
1801 		pr_debug("failed %d to resume KFD\n", r);
1802 	}
1803 
1804 	pr_debug("restore svm ranges successfully\n");
1805 
1806 out_reschedule:
1807 	mutex_unlock(&svms->lock);
1808 	mmap_write_unlock(mm);
1809 	mutex_unlock(&process_info->lock);
1810 
1811 	/* If validation failed, reschedule another attempt */
1812 	if (evicted_ranges) {
1813 		pr_debug("reschedule to restore svm range\n");
1814 		schedule_delayed_work(&svms->restore_work,
1815 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1816 
1817 		kfd_smi_event_queue_restore_rescheduled(mm);
1818 	}
1819 	mmput(mm);
1820 }
1821 
1822 /**
1823  * svm_range_evict - evict svm range
1824  * @prange: svm range structure
1825  * @mm: current process mm_struct
1826  * @start: starting process queue number
1827  * @last: last process queue number
1828  * @event: mmu notifier event when range is evicted or migrated
1829  *
1830  * Stop all queues of the process to ensure GPU doesn't access the memory, then
1831  * return to let CPU evict the buffer and proceed CPU pagetable update.
1832  *
1833  * Don't need use lock to sync cpu pagetable invalidation with GPU execution.
1834  * If invalidation happens while restore work is running, restore work will
1835  * restart to ensure to get the latest CPU pages mapping to GPU, then start
1836  * the queues.
1837  */
1838 static int
1839 svm_range_evict(struct svm_range *prange, struct mm_struct *mm,
1840 		unsigned long start, unsigned long last,
1841 		enum mmu_notifier_event event)
1842 {
1843 	struct svm_range_list *svms = prange->svms;
1844 	struct svm_range *pchild;
1845 	struct kfd_process *p;
1846 	int r = 0;
1847 
1848 	p = container_of(svms, struct kfd_process, svms);
1849 
1850 	pr_debug("invalidate svms 0x%p prange [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
1851 		 svms, prange->start, prange->last, start, last);
1852 
1853 	if (!p->xnack_enabled ||
1854 	    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) {
1855 		int evicted_ranges;
1856 		bool mapped = prange->mapped_to_gpu;
1857 
1858 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1859 			if (!pchild->mapped_to_gpu)
1860 				continue;
1861 			mapped = true;
1862 			mutex_lock_nested(&pchild->lock, 1);
1863 			if (pchild->start <= last && pchild->last >= start) {
1864 				pr_debug("increment pchild invalid [0x%lx 0x%lx]\n",
1865 					 pchild->start, pchild->last);
1866 				atomic_inc(&pchild->invalid);
1867 			}
1868 			mutex_unlock(&pchild->lock);
1869 		}
1870 
1871 		if (!mapped)
1872 			return r;
1873 
1874 		if (prange->start <= last && prange->last >= start)
1875 			atomic_inc(&prange->invalid);
1876 
1877 		evicted_ranges = atomic_inc_return(&svms->evicted_ranges);
1878 		if (evicted_ranges != 1)
1879 			return r;
1880 
1881 		pr_debug("evicting svms 0x%p range [0x%lx 0x%lx]\n",
1882 			 prange->svms, prange->start, prange->last);
1883 
1884 		/* First eviction, stop the queues */
1885 		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_SVM);
1886 		if (r)
1887 			pr_debug("failed to quiesce KFD\n");
1888 
1889 		pr_debug("schedule to restore svm %p ranges\n", svms);
1890 		schedule_delayed_work(&svms->restore_work,
1891 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1892 	} else {
1893 		unsigned long s, l;
1894 		uint32_t trigger;
1895 
1896 		if (event == MMU_NOTIFY_MIGRATE)
1897 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY_MIGRATE;
1898 		else
1899 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY;
1900 
1901 		pr_debug("invalidate unmap svms 0x%p [0x%lx 0x%lx] from GPUs\n",
1902 			 prange->svms, start, last);
1903 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1904 			mutex_lock_nested(&pchild->lock, 1);
1905 			s = max(start, pchild->start);
1906 			l = min(last, pchild->last);
1907 			if (l >= s)
1908 				svm_range_unmap_from_gpus(pchild, s, l, trigger);
1909 			mutex_unlock(&pchild->lock);
1910 		}
1911 		s = max(start, prange->start);
1912 		l = min(last, prange->last);
1913 		if (l >= s)
1914 			svm_range_unmap_from_gpus(prange, s, l, trigger);
1915 	}
1916 
1917 	return r;
1918 }
1919 
1920 static struct svm_range *svm_range_clone(struct svm_range *old)
1921 {
1922 	struct svm_range *new;
1923 
1924 	new = svm_range_new(old->svms, old->start, old->last, false);
1925 	if (!new)
1926 		return NULL;
1927 
1928 	if (old->svm_bo) {
1929 		new->ttm_res = old->ttm_res;
1930 		new->offset = old->offset;
1931 		new->svm_bo = svm_range_bo_ref(old->svm_bo);
1932 		spin_lock(&new->svm_bo->list_lock);
1933 		list_add(&new->svm_bo_list, &new->svm_bo->range_list);
1934 		spin_unlock(&new->svm_bo->list_lock);
1935 	}
1936 	new->flags = old->flags;
1937 	new->preferred_loc = old->preferred_loc;
1938 	new->prefetch_loc = old->prefetch_loc;
1939 	new->actual_loc = old->actual_loc;
1940 	new->granularity = old->granularity;
1941 	new->mapped_to_gpu = old->mapped_to_gpu;
1942 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
1943 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
1944 
1945 	return new;
1946 }
1947 
1948 void svm_range_set_max_pages(struct amdgpu_device *adev)
1949 {
1950 	uint64_t max_pages;
1951 	uint64_t pages, _pages;
1952 	uint64_t min_pages = 0;
1953 	int i, id;
1954 
1955 	for (i = 0; i < adev->kfd.dev->num_nodes; i++) {
1956 		if (adev->kfd.dev->nodes[i]->xcp)
1957 			id = adev->kfd.dev->nodes[i]->xcp->id;
1958 		else
1959 			id = -1;
1960 		pages = KFD_XCP_MEMORY_SIZE(adev, id) >> 17;
1961 		pages = clamp(pages, 1ULL << 9, 1ULL << 18);
1962 		pages = rounddown_pow_of_two(pages);
1963 		min_pages = min_not_zero(min_pages, pages);
1964 	}
1965 
1966 	do {
1967 		max_pages = READ_ONCE(max_svm_range_pages);
1968 		_pages = min_not_zero(max_pages, min_pages);
1969 	} while (cmpxchg(&max_svm_range_pages, max_pages, _pages) != max_pages);
1970 }
1971 
1972 static int
1973 svm_range_split_new(struct svm_range_list *svms, uint64_t start, uint64_t last,
1974 		    uint64_t max_pages, struct list_head *insert_list,
1975 		    struct list_head *update_list)
1976 {
1977 	struct svm_range *prange;
1978 	uint64_t l;
1979 
1980 	pr_debug("max_svm_range_pages 0x%llx adding [0x%llx 0x%llx]\n",
1981 		 max_pages, start, last);
1982 
1983 	while (last >= start) {
1984 		l = min(last, ALIGN_DOWN(start + max_pages, max_pages) - 1);
1985 
1986 		prange = svm_range_new(svms, start, l, true);
1987 		if (!prange)
1988 			return -ENOMEM;
1989 		list_add(&prange->list, insert_list);
1990 		list_add(&prange->update_list, update_list);
1991 
1992 		start = l + 1;
1993 	}
1994 	return 0;
1995 }
1996 
1997 /**
1998  * svm_range_add - add svm range and handle overlap
1999  * @p: the range add to this process svms
2000  * @start: page size aligned
2001  * @size: page size aligned
2002  * @nattr: number of attributes
2003  * @attrs: array of attributes
2004  * @update_list: output, the ranges need validate and update GPU mapping
2005  * @insert_list: output, the ranges need insert to svms
2006  * @remove_list: output, the ranges are replaced and need remove from svms
2007  *
2008  * Check if the virtual address range has overlap with any existing ranges,
2009  * split partly overlapping ranges and add new ranges in the gaps. All changes
2010  * should be applied to the range_list and interval tree transactionally. If
2011  * any range split or allocation fails, the entire update fails. Therefore any
2012  * existing overlapping svm_ranges are cloned and the original svm_ranges left
2013  * unchanged.
2014  *
2015  * If the transaction succeeds, the caller can update and insert clones and
2016  * new ranges, then free the originals.
2017  *
2018  * Otherwise the caller can free the clones and new ranges, while the old
2019  * svm_ranges remain unchanged.
2020  *
2021  * Context: Process context, caller must hold svms->lock
2022  *
2023  * Return:
2024  * 0 - OK, otherwise error code
2025  */
2026 static int
2027 svm_range_add(struct kfd_process *p, uint64_t start, uint64_t size,
2028 	      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
2029 	      struct list_head *update_list, struct list_head *insert_list,
2030 	      struct list_head *remove_list)
2031 {
2032 	unsigned long last = start + size - 1UL;
2033 	struct svm_range_list *svms = &p->svms;
2034 	struct interval_tree_node *node;
2035 	struct svm_range *prange;
2036 	struct svm_range *tmp;
2037 	struct list_head new_list;
2038 	int r = 0;
2039 
2040 	pr_debug("svms 0x%p [0x%llx 0x%lx]\n", &p->svms, start, last);
2041 
2042 	INIT_LIST_HEAD(update_list);
2043 	INIT_LIST_HEAD(insert_list);
2044 	INIT_LIST_HEAD(remove_list);
2045 	INIT_LIST_HEAD(&new_list);
2046 
2047 	node = interval_tree_iter_first(&svms->objects, start, last);
2048 	while (node) {
2049 		struct interval_tree_node *next;
2050 		unsigned long next_start;
2051 
2052 		pr_debug("found overlap node [0x%lx 0x%lx]\n", node->start,
2053 			 node->last);
2054 
2055 		prange = container_of(node, struct svm_range, it_node);
2056 		next = interval_tree_iter_next(node, start, last);
2057 		next_start = min(node->last, last) + 1;
2058 
2059 		if (svm_range_is_same_attrs(p, prange, nattr, attrs)) {
2060 			/* nothing to do */
2061 		} else if (node->start < start || node->last > last) {
2062 			/* node intersects the update range and its attributes
2063 			 * will change. Clone and split it, apply updates only
2064 			 * to the overlapping part
2065 			 */
2066 			struct svm_range *old = prange;
2067 
2068 			prange = svm_range_clone(old);
2069 			if (!prange) {
2070 				r = -ENOMEM;
2071 				goto out;
2072 			}
2073 
2074 			list_add(&old->update_list, remove_list);
2075 			list_add(&prange->list, insert_list);
2076 			list_add(&prange->update_list, update_list);
2077 
2078 			if (node->start < start) {
2079 				pr_debug("change old range start\n");
2080 				r = svm_range_split_head(prange, start,
2081 							 insert_list);
2082 				if (r)
2083 					goto out;
2084 			}
2085 			if (node->last > last) {
2086 				pr_debug("change old range last\n");
2087 				r = svm_range_split_tail(prange, last,
2088 							 insert_list);
2089 				if (r)
2090 					goto out;
2091 			}
2092 		} else {
2093 			/* The node is contained within start..last,
2094 			 * just update it
2095 			 */
2096 			list_add(&prange->update_list, update_list);
2097 		}
2098 
2099 		/* insert a new node if needed */
2100 		if (node->start > start) {
2101 			r = svm_range_split_new(svms, start, node->start - 1,
2102 						READ_ONCE(max_svm_range_pages),
2103 						&new_list, update_list);
2104 			if (r)
2105 				goto out;
2106 		}
2107 
2108 		node = next;
2109 		start = next_start;
2110 	}
2111 
2112 	/* add a final range at the end if needed */
2113 	if (start <= last)
2114 		r = svm_range_split_new(svms, start, last,
2115 					READ_ONCE(max_svm_range_pages),
2116 					&new_list, update_list);
2117 
2118 out:
2119 	if (r) {
2120 		list_for_each_entry_safe(prange, tmp, insert_list, list)
2121 			svm_range_free(prange, false);
2122 		list_for_each_entry_safe(prange, tmp, &new_list, list)
2123 			svm_range_free(prange, true);
2124 	} else {
2125 		list_splice(&new_list, insert_list);
2126 	}
2127 
2128 	return r;
2129 }
2130 
2131 static void
2132 svm_range_update_notifier_and_interval_tree(struct mm_struct *mm,
2133 					    struct svm_range *prange)
2134 {
2135 	unsigned long start;
2136 	unsigned long last;
2137 
2138 	start = prange->notifier.interval_tree.start >> PAGE_SHIFT;
2139 	last = prange->notifier.interval_tree.last >> PAGE_SHIFT;
2140 
2141 	if (prange->start == start && prange->last == last)
2142 		return;
2143 
2144 	pr_debug("up notifier 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
2145 		  prange->svms, prange, start, last, prange->start,
2146 		  prange->last);
2147 
2148 	if (start != 0 && last != 0) {
2149 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
2150 		svm_range_remove_notifier(prange);
2151 	}
2152 	prange->it_node.start = prange->start;
2153 	prange->it_node.last = prange->last;
2154 
2155 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
2156 	svm_range_add_notifier_locked(mm, prange);
2157 }
2158 
2159 static void
2160 svm_range_handle_list_op(struct svm_range_list *svms, struct svm_range *prange,
2161 			 struct mm_struct *mm)
2162 {
2163 	switch (prange->work_item.op) {
2164 	case SVM_OP_NULL:
2165 		pr_debug("NULL OP 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2166 			 svms, prange, prange->start, prange->last);
2167 		break;
2168 	case SVM_OP_UNMAP_RANGE:
2169 		pr_debug("remove 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2170 			 svms, prange, prange->start, prange->last);
2171 		svm_range_unlink(prange);
2172 		svm_range_remove_notifier(prange);
2173 		svm_range_free(prange, true);
2174 		break;
2175 	case SVM_OP_UPDATE_RANGE_NOTIFIER:
2176 		pr_debug("update notifier 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2177 			 svms, prange, prange->start, prange->last);
2178 		svm_range_update_notifier_and_interval_tree(mm, prange);
2179 		break;
2180 	case SVM_OP_UPDATE_RANGE_NOTIFIER_AND_MAP:
2181 		pr_debug("update and map 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2182 			 svms, prange, prange->start, prange->last);
2183 		svm_range_update_notifier_and_interval_tree(mm, prange);
2184 		/* TODO: implement deferred validation and mapping */
2185 		break;
2186 	case SVM_OP_ADD_RANGE:
2187 		pr_debug("add 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms, prange,
2188 			 prange->start, prange->last);
2189 		svm_range_add_to_svms(prange);
2190 		svm_range_add_notifier_locked(mm, prange);
2191 		break;
2192 	case SVM_OP_ADD_RANGE_AND_MAP:
2193 		pr_debug("add and map 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms,
2194 			 prange, prange->start, prange->last);
2195 		svm_range_add_to_svms(prange);
2196 		svm_range_add_notifier_locked(mm, prange);
2197 		/* TODO: implement deferred validation and mapping */
2198 		break;
2199 	default:
2200 		WARN_ONCE(1, "Unknown prange 0x%p work op %d\n", prange,
2201 			 prange->work_item.op);
2202 	}
2203 }
2204 
2205 static void svm_range_drain_retry_fault(struct svm_range_list *svms)
2206 {
2207 	struct kfd_process_device *pdd;
2208 	struct kfd_process *p;
2209 	int drain;
2210 	uint32_t i;
2211 
2212 	p = container_of(svms, struct kfd_process, svms);
2213 
2214 restart:
2215 	drain = atomic_read(&svms->drain_pagefaults);
2216 	if (!drain)
2217 		return;
2218 
2219 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2220 		pdd = p->pdds[i];
2221 		if (!pdd)
2222 			continue;
2223 
2224 		pr_debug("drain retry fault gpu %d svms %p\n", i, svms);
2225 
2226 		amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2227 				pdd->dev->adev->irq.retry_cam_enabled ?
2228 				&pdd->dev->adev->irq.ih :
2229 				&pdd->dev->adev->irq.ih1);
2230 
2231 		if (pdd->dev->adev->irq.retry_cam_enabled)
2232 			amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2233 				&pdd->dev->adev->irq.ih_soft);
2234 
2235 
2236 		pr_debug("drain retry fault gpu %d svms 0x%p done\n", i, svms);
2237 	}
2238 	if (atomic_cmpxchg(&svms->drain_pagefaults, drain, 0) != drain)
2239 		goto restart;
2240 }
2241 
2242 static void svm_range_deferred_list_work(struct work_struct *work)
2243 {
2244 	struct svm_range_list *svms;
2245 	struct svm_range *prange;
2246 	struct mm_struct *mm;
2247 
2248 	svms = container_of(work, struct svm_range_list, deferred_list_work);
2249 	pr_debug("enter svms 0x%p\n", svms);
2250 
2251 	spin_lock(&svms->deferred_list_lock);
2252 	while (!list_empty(&svms->deferred_range_list)) {
2253 		prange = list_first_entry(&svms->deferred_range_list,
2254 					  struct svm_range, deferred_list);
2255 		spin_unlock(&svms->deferred_list_lock);
2256 
2257 		pr_debug("prange 0x%p [0x%lx 0x%lx] op %d\n", prange,
2258 			 prange->start, prange->last, prange->work_item.op);
2259 
2260 		mm = prange->work_item.mm;
2261 retry:
2262 		mmap_write_lock(mm);
2263 
2264 		/* Checking for the need to drain retry faults must be inside
2265 		 * mmap write lock to serialize with munmap notifiers.
2266 		 */
2267 		if (unlikely(atomic_read(&svms->drain_pagefaults))) {
2268 			mmap_write_unlock(mm);
2269 			svm_range_drain_retry_fault(svms);
2270 			goto retry;
2271 		}
2272 
2273 		/* Remove from deferred_list must be inside mmap write lock, for
2274 		 * two race cases:
2275 		 * 1. unmap_from_cpu may change work_item.op and add the range
2276 		 *    to deferred_list again, cause use after free bug.
2277 		 * 2. svm_range_list_lock_and_flush_work may hold mmap write
2278 		 *    lock and continue because deferred_list is empty, but
2279 		 *    deferred_list work is actually waiting for mmap lock.
2280 		 */
2281 		spin_lock(&svms->deferred_list_lock);
2282 		list_del_init(&prange->deferred_list);
2283 		spin_unlock(&svms->deferred_list_lock);
2284 
2285 		mutex_lock(&svms->lock);
2286 		mutex_lock(&prange->migrate_mutex);
2287 		while (!list_empty(&prange->child_list)) {
2288 			struct svm_range *pchild;
2289 
2290 			pchild = list_first_entry(&prange->child_list,
2291 						struct svm_range, child_list);
2292 			pr_debug("child prange 0x%p op %d\n", pchild,
2293 				 pchild->work_item.op);
2294 			list_del_init(&pchild->child_list);
2295 			svm_range_handle_list_op(svms, pchild, mm);
2296 		}
2297 		mutex_unlock(&prange->migrate_mutex);
2298 
2299 		svm_range_handle_list_op(svms, prange, mm);
2300 		mutex_unlock(&svms->lock);
2301 		mmap_write_unlock(mm);
2302 
2303 		/* Pairs with mmget in svm_range_add_list_work */
2304 		mmput(mm);
2305 
2306 		spin_lock(&svms->deferred_list_lock);
2307 	}
2308 	spin_unlock(&svms->deferred_list_lock);
2309 	pr_debug("exit svms 0x%p\n", svms);
2310 }
2311 
2312 void
2313 svm_range_add_list_work(struct svm_range_list *svms, struct svm_range *prange,
2314 			struct mm_struct *mm, enum svm_work_list_ops op)
2315 {
2316 	spin_lock(&svms->deferred_list_lock);
2317 	/* if prange is on the deferred list */
2318 	if (!list_empty(&prange->deferred_list)) {
2319 		pr_debug("update exist prange 0x%p work op %d\n", prange, op);
2320 		WARN_ONCE(prange->work_item.mm != mm, "unmatch mm\n");
2321 		if (op != SVM_OP_NULL &&
2322 		    prange->work_item.op != SVM_OP_UNMAP_RANGE)
2323 			prange->work_item.op = op;
2324 	} else {
2325 		prange->work_item.op = op;
2326 
2327 		/* Pairs with mmput in deferred_list_work */
2328 		mmget(mm);
2329 		prange->work_item.mm = mm;
2330 		list_add_tail(&prange->deferred_list,
2331 			      &prange->svms->deferred_range_list);
2332 		pr_debug("add prange 0x%p [0x%lx 0x%lx] to work list op %d\n",
2333 			 prange, prange->start, prange->last, op);
2334 	}
2335 	spin_unlock(&svms->deferred_list_lock);
2336 }
2337 
2338 void schedule_deferred_list_work(struct svm_range_list *svms)
2339 {
2340 	spin_lock(&svms->deferred_list_lock);
2341 	if (!list_empty(&svms->deferred_range_list))
2342 		schedule_work(&svms->deferred_list_work);
2343 	spin_unlock(&svms->deferred_list_lock);
2344 }
2345 
2346 static void
2347 svm_range_unmap_split(struct mm_struct *mm, struct svm_range *parent,
2348 		      struct svm_range *prange, unsigned long start,
2349 		      unsigned long last)
2350 {
2351 	struct svm_range *head;
2352 	struct svm_range *tail;
2353 
2354 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2355 		pr_debug("prange 0x%p [0x%lx 0x%lx] is already freed\n", prange,
2356 			 prange->start, prange->last);
2357 		return;
2358 	}
2359 	if (start > prange->last || last < prange->start)
2360 		return;
2361 
2362 	head = tail = prange;
2363 	if (start > prange->start)
2364 		svm_range_split(prange, prange->start, start - 1, &tail);
2365 	if (last < tail->last)
2366 		svm_range_split(tail, last + 1, tail->last, &head);
2367 
2368 	if (head != prange && tail != prange) {
2369 		svm_range_add_child(parent, mm, head, SVM_OP_UNMAP_RANGE);
2370 		svm_range_add_child(parent, mm, tail, SVM_OP_ADD_RANGE);
2371 	} else if (tail != prange) {
2372 		svm_range_add_child(parent, mm, tail, SVM_OP_UNMAP_RANGE);
2373 	} else if (head != prange) {
2374 		svm_range_add_child(parent, mm, head, SVM_OP_UNMAP_RANGE);
2375 	} else if (parent != prange) {
2376 		prange->work_item.op = SVM_OP_UNMAP_RANGE;
2377 	}
2378 }
2379 
2380 static void
2381 svm_range_unmap_from_cpu(struct mm_struct *mm, struct svm_range *prange,
2382 			 unsigned long start, unsigned long last)
2383 {
2384 	uint32_t trigger = KFD_SVM_UNMAP_TRIGGER_UNMAP_FROM_CPU;
2385 	struct svm_range_list *svms;
2386 	struct svm_range *pchild;
2387 	struct kfd_process *p;
2388 	unsigned long s, l;
2389 	bool unmap_parent;
2390 
2391 	p = kfd_lookup_process_by_mm(mm);
2392 	if (!p)
2393 		return;
2394 	svms = &p->svms;
2395 
2396 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n", svms,
2397 		 prange, prange->start, prange->last, start, last);
2398 
2399 	/* Make sure pending page faults are drained in the deferred worker
2400 	 * before the range is freed to avoid straggler interrupts on
2401 	 * unmapped memory causing "phantom faults".
2402 	 */
2403 	atomic_inc(&svms->drain_pagefaults);
2404 
2405 	unmap_parent = start <= prange->start && last >= prange->last;
2406 
2407 	list_for_each_entry(pchild, &prange->child_list, child_list) {
2408 		mutex_lock_nested(&pchild->lock, 1);
2409 		s = max(start, pchild->start);
2410 		l = min(last, pchild->last);
2411 		if (l >= s)
2412 			svm_range_unmap_from_gpus(pchild, s, l, trigger);
2413 		svm_range_unmap_split(mm, prange, pchild, start, last);
2414 		mutex_unlock(&pchild->lock);
2415 	}
2416 	s = max(start, prange->start);
2417 	l = min(last, prange->last);
2418 	if (l >= s)
2419 		svm_range_unmap_from_gpus(prange, s, l, trigger);
2420 	svm_range_unmap_split(mm, prange, prange, start, last);
2421 
2422 	if (unmap_parent)
2423 		svm_range_add_list_work(svms, prange, mm, SVM_OP_UNMAP_RANGE);
2424 	else
2425 		svm_range_add_list_work(svms, prange, mm,
2426 					SVM_OP_UPDATE_RANGE_NOTIFIER);
2427 	schedule_deferred_list_work(svms);
2428 
2429 	kfd_unref_process(p);
2430 }
2431 
2432 /**
2433  * svm_range_cpu_invalidate_pagetables - interval notifier callback
2434  * @mni: mmu_interval_notifier struct
2435  * @range: mmu_notifier_range struct
2436  * @cur_seq: value to pass to mmu_interval_set_seq()
2437  *
2438  * If event is MMU_NOTIFY_UNMAP, this is from CPU unmap range, otherwise, it
2439  * is from migration, or CPU page invalidation callback.
2440  *
2441  * For unmap event, unmap range from GPUs, remove prange from svms in a delayed
2442  * work thread, and split prange if only part of prange is unmapped.
2443  *
2444  * For invalidation event, if GPU retry fault is not enabled, evict the queues,
2445  * then schedule svm_range_restore_work to update GPU mapping and resume queues.
2446  * If GPU retry fault is enabled, unmap the svm range from GPU, retry fault will
2447  * update GPU mapping to recover.
2448  *
2449  * Context: mmap lock, notifier_invalidate_start lock are held
2450  *          for invalidate event, prange lock is held if this is from migration
2451  */
2452 static bool
2453 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
2454 				    const struct mmu_notifier_range *range,
2455 				    unsigned long cur_seq)
2456 {
2457 	struct svm_range *prange;
2458 	unsigned long start;
2459 	unsigned long last;
2460 
2461 	if (range->event == MMU_NOTIFY_RELEASE)
2462 		return true;
2463 	if (!mmget_not_zero(mni->mm))
2464 		return true;
2465 
2466 	start = mni->interval_tree.start;
2467 	last = mni->interval_tree.last;
2468 	start = max(start, range->start) >> PAGE_SHIFT;
2469 	last = min(last, range->end - 1) >> PAGE_SHIFT;
2470 	pr_debug("[0x%lx 0x%lx] range[0x%lx 0x%lx] notifier[0x%lx 0x%lx] %d\n",
2471 		 start, last, range->start >> PAGE_SHIFT,
2472 		 (range->end - 1) >> PAGE_SHIFT,
2473 		 mni->interval_tree.start >> PAGE_SHIFT,
2474 		 mni->interval_tree.last >> PAGE_SHIFT, range->event);
2475 
2476 	prange = container_of(mni, struct svm_range, notifier);
2477 
2478 	svm_range_lock(prange);
2479 	mmu_interval_set_seq(mni, cur_seq);
2480 
2481 	switch (range->event) {
2482 	case MMU_NOTIFY_UNMAP:
2483 		svm_range_unmap_from_cpu(mni->mm, prange, start, last);
2484 		break;
2485 	default:
2486 		svm_range_evict(prange, mni->mm, start, last, range->event);
2487 		break;
2488 	}
2489 
2490 	svm_range_unlock(prange);
2491 	mmput(mni->mm);
2492 
2493 	return true;
2494 }
2495 
2496 /**
2497  * svm_range_from_addr - find svm range from fault address
2498  * @svms: svm range list header
2499  * @addr: address to search range interval tree, in pages
2500  * @parent: parent range if range is on child list
2501  *
2502  * Context: The caller must hold svms->lock
2503  *
2504  * Return: the svm_range found or NULL
2505  */
2506 struct svm_range *
2507 svm_range_from_addr(struct svm_range_list *svms, unsigned long addr,
2508 		    struct svm_range **parent)
2509 {
2510 	struct interval_tree_node *node;
2511 	struct svm_range *prange;
2512 	struct svm_range *pchild;
2513 
2514 	node = interval_tree_iter_first(&svms->objects, addr, addr);
2515 	if (!node)
2516 		return NULL;
2517 
2518 	prange = container_of(node, struct svm_range, it_node);
2519 	pr_debug("address 0x%lx prange [0x%lx 0x%lx] node [0x%lx 0x%lx]\n",
2520 		 addr, prange->start, prange->last, node->start, node->last);
2521 
2522 	if (addr >= prange->start && addr <= prange->last) {
2523 		if (parent)
2524 			*parent = prange;
2525 		return prange;
2526 	}
2527 	list_for_each_entry(pchild, &prange->child_list, child_list)
2528 		if (addr >= pchild->start && addr <= pchild->last) {
2529 			pr_debug("found address 0x%lx pchild [0x%lx 0x%lx]\n",
2530 				 addr, pchild->start, pchild->last);
2531 			if (parent)
2532 				*parent = prange;
2533 			return pchild;
2534 		}
2535 
2536 	return NULL;
2537 }
2538 
2539 /* svm_range_best_restore_location - decide the best fault restore location
2540  * @prange: svm range structure
2541  * @adev: the GPU on which vm fault happened
2542  *
2543  * This is only called when xnack is on, to decide the best location to restore
2544  * the range mapping after GPU vm fault. Caller uses the best location to do
2545  * migration if actual loc is not best location, then update GPU page table
2546  * mapping to the best location.
2547  *
2548  * If the preferred loc is accessible by faulting GPU, use preferred loc.
2549  * If vm fault gpu idx is on range ACCESSIBLE bitmap, best_loc is vm fault gpu
2550  * If vm fault gpu idx is on range ACCESSIBLE_IN_PLACE bitmap, then
2551  *    if range actual loc is cpu, best_loc is cpu
2552  *    if vm fault gpu is on xgmi same hive of range actual loc gpu, best_loc is
2553  *    range actual loc.
2554  * Otherwise, GPU no access, best_loc is -1.
2555  *
2556  * Return:
2557  * -1 means vm fault GPU no access
2558  * 0 for CPU or GPU id
2559  */
2560 static int32_t
2561 svm_range_best_restore_location(struct svm_range *prange,
2562 				struct kfd_node *node,
2563 				int32_t *gpuidx)
2564 {
2565 	struct kfd_node *bo_node, *preferred_node;
2566 	struct kfd_process *p;
2567 	uint32_t gpuid;
2568 	int r;
2569 
2570 	p = container_of(prange->svms, struct kfd_process, svms);
2571 
2572 	r = kfd_process_gpuid_from_node(p, node, &gpuid, gpuidx);
2573 	if (r < 0) {
2574 		pr_debug("failed to get gpuid from kgd\n");
2575 		return -1;
2576 	}
2577 
2578 	if (node->adev->gmc.is_app_apu)
2579 		return 0;
2580 
2581 	if (prange->preferred_loc == gpuid ||
2582 	    prange->preferred_loc == KFD_IOCTL_SVM_LOCATION_SYSMEM) {
2583 		return prange->preferred_loc;
2584 	} else if (prange->preferred_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
2585 		preferred_node = svm_range_get_node_by_id(prange, prange->preferred_loc);
2586 		if (preferred_node && svm_nodes_in_same_hive(node, preferred_node))
2587 			return prange->preferred_loc;
2588 		/* fall through */
2589 	}
2590 
2591 	if (test_bit(*gpuidx, prange->bitmap_access))
2592 		return gpuid;
2593 
2594 	if (test_bit(*gpuidx, prange->bitmap_aip)) {
2595 		if (!prange->actual_loc)
2596 			return 0;
2597 
2598 		bo_node = svm_range_get_node_by_id(prange, prange->actual_loc);
2599 		if (bo_node && svm_nodes_in_same_hive(node, bo_node))
2600 			return prange->actual_loc;
2601 		else
2602 			return 0;
2603 	}
2604 
2605 	return -1;
2606 }
2607 
2608 static int
2609 svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
2610 			       unsigned long *start, unsigned long *last,
2611 			       bool *is_heap_stack)
2612 {
2613 	struct vm_area_struct *vma;
2614 	struct interval_tree_node *node;
2615 	unsigned long start_limit, end_limit;
2616 
2617 	vma = vma_lookup(p->mm, addr << PAGE_SHIFT);
2618 	if (!vma) {
2619 		pr_debug("VMA does not exist in address [0x%llx]\n", addr);
2620 		return -EFAULT;
2621 	}
2622 
2623 	*is_heap_stack = (vma->vm_start <= vma->vm_mm->brk &&
2624 			  vma->vm_end >= vma->vm_mm->start_brk) ||
2625 			 (vma->vm_start <= vma->vm_mm->start_stack &&
2626 			  vma->vm_end >= vma->vm_mm->start_stack);
2627 
2628 	start_limit = max(vma->vm_start >> PAGE_SHIFT,
2629 		      (unsigned long)ALIGN_DOWN(addr, 2UL << 8));
2630 	end_limit = min(vma->vm_end >> PAGE_SHIFT,
2631 		    (unsigned long)ALIGN(addr + 1, 2UL << 8));
2632 	/* First range that starts after the fault address */
2633 	node = interval_tree_iter_first(&p->svms.objects, addr + 1, ULONG_MAX);
2634 	if (node) {
2635 		end_limit = min(end_limit, node->start);
2636 		/* Last range that ends before the fault address */
2637 		node = container_of(rb_prev(&node->rb),
2638 				    struct interval_tree_node, rb);
2639 	} else {
2640 		/* Last range must end before addr because
2641 		 * there was no range after addr
2642 		 */
2643 		node = container_of(rb_last(&p->svms.objects.rb_root),
2644 				    struct interval_tree_node, rb);
2645 	}
2646 	if (node) {
2647 		if (node->last >= addr) {
2648 			WARN(1, "Overlap with prev node and page fault addr\n");
2649 			return -EFAULT;
2650 		}
2651 		start_limit = max(start_limit, node->last + 1);
2652 	}
2653 
2654 	*start = start_limit;
2655 	*last = end_limit - 1;
2656 
2657 	pr_debug("vma [0x%lx 0x%lx] range [0x%lx 0x%lx] is_heap_stack %d\n",
2658 		 vma->vm_start >> PAGE_SHIFT, vma->vm_end >> PAGE_SHIFT,
2659 		 *start, *last, *is_heap_stack);
2660 
2661 	return 0;
2662 }
2663 
2664 static int
2665 svm_range_check_vm_userptr(struct kfd_process *p, uint64_t start, uint64_t last,
2666 			   uint64_t *bo_s, uint64_t *bo_l)
2667 {
2668 	struct amdgpu_bo_va_mapping *mapping;
2669 	struct interval_tree_node *node;
2670 	struct amdgpu_bo *bo = NULL;
2671 	unsigned long userptr;
2672 	uint32_t i;
2673 	int r;
2674 
2675 	for (i = 0; i < p->n_pdds; i++) {
2676 		struct amdgpu_vm *vm;
2677 
2678 		if (!p->pdds[i]->drm_priv)
2679 			continue;
2680 
2681 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
2682 		r = amdgpu_bo_reserve(vm->root.bo, false);
2683 		if (r)
2684 			return r;
2685 
2686 		/* Check userptr by searching entire vm->va interval tree */
2687 		node = interval_tree_iter_first(&vm->va, 0, ~0ULL);
2688 		while (node) {
2689 			mapping = container_of((struct rb_node *)node,
2690 					       struct amdgpu_bo_va_mapping, rb);
2691 			bo = mapping->bo_va->base.bo;
2692 
2693 			if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm,
2694 							 start << PAGE_SHIFT,
2695 							 last << PAGE_SHIFT,
2696 							 &userptr)) {
2697 				node = interval_tree_iter_next(node, 0, ~0ULL);
2698 				continue;
2699 			}
2700 
2701 			pr_debug("[0x%llx 0x%llx] already userptr mapped\n",
2702 				 start, last);
2703 			if (bo_s && bo_l) {
2704 				*bo_s = userptr >> PAGE_SHIFT;
2705 				*bo_l = *bo_s + bo->tbo.ttm->num_pages - 1;
2706 			}
2707 			amdgpu_bo_unreserve(vm->root.bo);
2708 			return -EADDRINUSE;
2709 		}
2710 		amdgpu_bo_unreserve(vm->root.bo);
2711 	}
2712 	return 0;
2713 }
2714 
2715 static struct
2716 svm_range *svm_range_create_unregistered_range(struct kfd_node *node,
2717 						struct kfd_process *p,
2718 						struct mm_struct *mm,
2719 						int64_t addr)
2720 {
2721 	struct svm_range *prange = NULL;
2722 	unsigned long start, last;
2723 	uint32_t gpuid, gpuidx;
2724 	bool is_heap_stack;
2725 	uint64_t bo_s = 0;
2726 	uint64_t bo_l = 0;
2727 	int r;
2728 
2729 	if (svm_range_get_range_boundaries(p, addr, &start, &last,
2730 					   &is_heap_stack))
2731 		return NULL;
2732 
2733 	r = svm_range_check_vm(p, start, last, &bo_s, &bo_l);
2734 	if (r != -EADDRINUSE)
2735 		r = svm_range_check_vm_userptr(p, start, last, &bo_s, &bo_l);
2736 
2737 	if (r == -EADDRINUSE) {
2738 		if (addr >= bo_s && addr <= bo_l)
2739 			return NULL;
2740 
2741 		/* Create one page svm range if 2MB range overlapping */
2742 		start = addr;
2743 		last = addr;
2744 	}
2745 
2746 	prange = svm_range_new(&p->svms, start, last, true);
2747 	if (!prange) {
2748 		pr_debug("Failed to create prange in address [0x%llx]\n", addr);
2749 		return NULL;
2750 	}
2751 	if (kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx)) {
2752 		pr_debug("failed to get gpuid from kgd\n");
2753 		svm_range_free(prange, true);
2754 		return NULL;
2755 	}
2756 
2757 	if (is_heap_stack)
2758 		prange->preferred_loc = KFD_IOCTL_SVM_LOCATION_SYSMEM;
2759 
2760 	svm_range_add_to_svms(prange);
2761 	svm_range_add_notifier_locked(mm, prange);
2762 
2763 	return prange;
2764 }
2765 
2766 /* svm_range_skip_recover - decide if prange can be recovered
2767  * @prange: svm range structure
2768  *
2769  * GPU vm retry fault handle skip recover the range for cases:
2770  * 1. prange is on deferred list to be removed after unmap, it is stale fault,
2771  *    deferred list work will drain the stale fault before free the prange.
2772  * 2. prange is on deferred list to add interval notifier after split, or
2773  * 3. prange is child range, it is split from parent prange, recover later
2774  *    after interval notifier is added.
2775  *
2776  * Return: true to skip recover, false to recover
2777  */
2778 static bool svm_range_skip_recover(struct svm_range *prange)
2779 {
2780 	struct svm_range_list *svms = prange->svms;
2781 
2782 	spin_lock(&svms->deferred_list_lock);
2783 	if (list_empty(&prange->deferred_list) &&
2784 	    list_empty(&prange->child_list)) {
2785 		spin_unlock(&svms->deferred_list_lock);
2786 		return false;
2787 	}
2788 	spin_unlock(&svms->deferred_list_lock);
2789 
2790 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2791 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] unmapped\n",
2792 			 svms, prange, prange->start, prange->last);
2793 		return true;
2794 	}
2795 	if (prange->work_item.op == SVM_OP_ADD_RANGE_AND_MAP ||
2796 	    prange->work_item.op == SVM_OP_ADD_RANGE) {
2797 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] not added yet\n",
2798 			 svms, prange, prange->start, prange->last);
2799 		return true;
2800 	}
2801 	return false;
2802 }
2803 
2804 static void
2805 svm_range_count_fault(struct kfd_node *node, struct kfd_process *p,
2806 		      int32_t gpuidx)
2807 {
2808 	struct kfd_process_device *pdd;
2809 
2810 	/* fault is on different page of same range
2811 	 * or fault is skipped to recover later
2812 	 * or fault is on invalid virtual address
2813 	 */
2814 	if (gpuidx == MAX_GPU_INSTANCE) {
2815 		uint32_t gpuid;
2816 		int r;
2817 
2818 		r = kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx);
2819 		if (r < 0)
2820 			return;
2821 	}
2822 
2823 	/* fault is recovered
2824 	 * or fault cannot recover because GPU no access on the range
2825 	 */
2826 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
2827 	if (pdd)
2828 		WRITE_ONCE(pdd->faults, pdd->faults + 1);
2829 }
2830 
2831 static bool
2832 svm_fault_allowed(struct vm_area_struct *vma, bool write_fault)
2833 {
2834 	unsigned long requested = VM_READ;
2835 
2836 	if (write_fault)
2837 		requested |= VM_WRITE;
2838 
2839 	pr_debug("requested 0x%lx, vma permission flags 0x%lx\n", requested,
2840 		vma->vm_flags);
2841 	return (vma->vm_flags & requested) == requested;
2842 }
2843 
2844 int
2845 svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
2846 			uint32_t vmid, uint32_t node_id,
2847 			uint64_t addr, bool write_fault)
2848 {
2849 	struct mm_struct *mm = NULL;
2850 	struct svm_range_list *svms;
2851 	struct svm_range *prange;
2852 	struct kfd_process *p;
2853 	ktime_t timestamp = ktime_get_boottime();
2854 	struct kfd_node *node;
2855 	int32_t best_loc;
2856 	int32_t gpuidx = MAX_GPU_INSTANCE;
2857 	bool write_locked = false;
2858 	struct vm_area_struct *vma;
2859 	bool migration = false;
2860 	int r = 0;
2861 
2862 	if (!KFD_IS_SVM_API_SUPPORTED(adev)) {
2863 		pr_debug("device does not support SVM\n");
2864 		return -EFAULT;
2865 	}
2866 
2867 	p = kfd_lookup_process_by_pasid(pasid);
2868 	if (!p) {
2869 		pr_debug("kfd process not founded pasid 0x%x\n", pasid);
2870 		return 0;
2871 	}
2872 	svms = &p->svms;
2873 
2874 	pr_debug("restoring svms 0x%p fault address 0x%llx\n", svms, addr);
2875 
2876 	if (atomic_read(&svms->drain_pagefaults)) {
2877 		pr_debug("draining retry fault, drop fault 0x%llx\n", addr);
2878 		r = 0;
2879 		goto out;
2880 	}
2881 
2882 	if (!p->xnack_enabled) {
2883 		pr_debug("XNACK not enabled for pasid 0x%x\n", pasid);
2884 		r = -EFAULT;
2885 		goto out;
2886 	}
2887 
2888 	/* p->lead_thread is available as kfd_process_wq_release flush the work
2889 	 * before releasing task ref.
2890 	 */
2891 	mm = get_task_mm(p->lead_thread);
2892 	if (!mm) {
2893 		pr_debug("svms 0x%p failed to get mm\n", svms);
2894 		r = 0;
2895 		goto out;
2896 	}
2897 
2898 	node = kfd_node_by_irq_ids(adev, node_id, vmid);
2899 	if (!node) {
2900 		pr_debug("kfd node does not exist node_id: %d, vmid: %d\n", node_id,
2901 			 vmid);
2902 		r = -EFAULT;
2903 		goto out;
2904 	}
2905 	mmap_read_lock(mm);
2906 retry_write_locked:
2907 	mutex_lock(&svms->lock);
2908 	prange = svm_range_from_addr(svms, addr, NULL);
2909 	if (!prange) {
2910 		pr_debug("failed to find prange svms 0x%p address [0x%llx]\n",
2911 			 svms, addr);
2912 		if (!write_locked) {
2913 			/* Need the write lock to create new range with MMU notifier.
2914 			 * Also flush pending deferred work to make sure the interval
2915 			 * tree is up to date before we add a new range
2916 			 */
2917 			mutex_unlock(&svms->lock);
2918 			mmap_read_unlock(mm);
2919 			mmap_write_lock(mm);
2920 			write_locked = true;
2921 			goto retry_write_locked;
2922 		}
2923 		prange = svm_range_create_unregistered_range(node, p, mm, addr);
2924 		if (!prange) {
2925 			pr_debug("failed to create unregistered range svms 0x%p address [0x%llx]\n",
2926 				 svms, addr);
2927 			mmap_write_downgrade(mm);
2928 			r = -EFAULT;
2929 			goto out_unlock_svms;
2930 		}
2931 	}
2932 	if (write_locked)
2933 		mmap_write_downgrade(mm);
2934 
2935 	mutex_lock(&prange->migrate_mutex);
2936 
2937 	if (svm_range_skip_recover(prange)) {
2938 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
2939 		r = 0;
2940 		goto out_unlock_range;
2941 	}
2942 
2943 	/* skip duplicate vm fault on different pages of same range */
2944 	if (ktime_before(timestamp, ktime_add_ns(prange->validate_timestamp,
2945 				AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING))) {
2946 		pr_debug("svms 0x%p [0x%lx %lx] already restored\n",
2947 			 svms, prange->start, prange->last);
2948 		r = 0;
2949 		goto out_unlock_range;
2950 	}
2951 
2952 	/* __do_munmap removed VMA, return success as we are handling stale
2953 	 * retry fault.
2954 	 */
2955 	vma = vma_lookup(mm, addr << PAGE_SHIFT);
2956 	if (!vma) {
2957 		pr_debug("address 0x%llx VMA is removed\n", addr);
2958 		r = 0;
2959 		goto out_unlock_range;
2960 	}
2961 
2962 	if (!svm_fault_allowed(vma, write_fault)) {
2963 		pr_debug("fault addr 0x%llx no %s permission\n", addr,
2964 			write_fault ? "write" : "read");
2965 		r = -EPERM;
2966 		goto out_unlock_range;
2967 	}
2968 
2969 	best_loc = svm_range_best_restore_location(prange, node, &gpuidx);
2970 	if (best_loc == -1) {
2971 		pr_debug("svms %p failed get best restore loc [0x%lx 0x%lx]\n",
2972 			 svms, prange->start, prange->last);
2973 		r = -EACCES;
2974 		goto out_unlock_range;
2975 	}
2976 
2977 	pr_debug("svms %p [0x%lx 0x%lx] best restore 0x%x, actual loc 0x%x\n",
2978 		 svms, prange->start, prange->last, best_loc,
2979 		 prange->actual_loc);
2980 
2981 	kfd_smi_event_page_fault_start(node, p->lead_thread->pid, addr,
2982 				       write_fault, timestamp);
2983 
2984 	if (prange->actual_loc != best_loc) {
2985 		migration = true;
2986 		if (best_loc) {
2987 			r = svm_migrate_to_vram(prange, best_loc, mm,
2988 					KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU);
2989 			if (r) {
2990 				pr_debug("svm_migrate_to_vram failed (%d) at %llx, falling back to system memory\n",
2991 					 r, addr);
2992 				/* Fallback to system memory if migration to
2993 				 * VRAM failed
2994 				 */
2995 				if (prange->actual_loc)
2996 					r = svm_migrate_vram_to_ram(prange, mm,
2997 					   KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU,
2998 					   NULL);
2999 				else
3000 					r = 0;
3001 			}
3002 		} else {
3003 			r = svm_migrate_vram_to_ram(prange, mm,
3004 					KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU,
3005 					NULL);
3006 		}
3007 		if (r) {
3008 			pr_debug("failed %d to migrate svms %p [0x%lx 0x%lx]\n",
3009 				 r, svms, prange->start, prange->last);
3010 			goto out_unlock_range;
3011 		}
3012 	}
3013 
3014 	r = svm_range_validate_and_map(mm, prange, gpuidx, false, false, false);
3015 	if (r)
3016 		pr_debug("failed %d to map svms 0x%p [0x%lx 0x%lx] to gpus\n",
3017 			 r, svms, prange->start, prange->last);
3018 
3019 	kfd_smi_event_page_fault_end(node, p->lead_thread->pid, addr,
3020 				     migration);
3021 
3022 out_unlock_range:
3023 	mutex_unlock(&prange->migrate_mutex);
3024 out_unlock_svms:
3025 	mutex_unlock(&svms->lock);
3026 	mmap_read_unlock(mm);
3027 
3028 	svm_range_count_fault(node, p, gpuidx);
3029 
3030 	mmput(mm);
3031 out:
3032 	kfd_unref_process(p);
3033 
3034 	if (r == -EAGAIN) {
3035 		pr_debug("recover vm fault later\n");
3036 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
3037 		r = 0;
3038 	}
3039 	return r;
3040 }
3041 
3042 int
3043 svm_range_switch_xnack_reserve_mem(struct kfd_process *p, bool xnack_enabled)
3044 {
3045 	struct svm_range *prange, *pchild;
3046 	uint64_t reserved_size = 0;
3047 	uint64_t size;
3048 	int r = 0;
3049 
3050 	pr_debug("switching xnack from %d to %d\n", p->xnack_enabled, xnack_enabled);
3051 
3052 	mutex_lock(&p->svms.lock);
3053 
3054 	list_for_each_entry(prange, &p->svms.list, list) {
3055 		svm_range_lock(prange);
3056 		list_for_each_entry(pchild, &prange->child_list, child_list) {
3057 			size = (pchild->last - pchild->start + 1) << PAGE_SHIFT;
3058 			if (xnack_enabled) {
3059 				amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3060 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3061 			} else {
3062 				r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3063 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3064 				if (r)
3065 					goto out_unlock;
3066 				reserved_size += size;
3067 			}
3068 		}
3069 
3070 		size = (prange->last - prange->start + 1) << PAGE_SHIFT;
3071 		if (xnack_enabled) {
3072 			amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3073 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3074 		} else {
3075 			r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3076 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3077 			if (r)
3078 				goto out_unlock;
3079 			reserved_size += size;
3080 		}
3081 out_unlock:
3082 		svm_range_unlock(prange);
3083 		if (r)
3084 			break;
3085 	}
3086 
3087 	if (r)
3088 		amdgpu_amdkfd_unreserve_mem_limit(NULL, reserved_size,
3089 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3090 	else
3091 		/* Change xnack mode must be inside svms lock, to avoid race with
3092 		 * svm_range_deferred_list_work unreserve memory in parallel.
3093 		 */
3094 		p->xnack_enabled = xnack_enabled;
3095 
3096 	mutex_unlock(&p->svms.lock);
3097 	return r;
3098 }
3099 
3100 void svm_range_list_fini(struct kfd_process *p)
3101 {
3102 	struct svm_range *prange;
3103 	struct svm_range *next;
3104 
3105 	pr_debug("pasid 0x%x svms 0x%p\n", p->pasid, &p->svms);
3106 
3107 	cancel_delayed_work_sync(&p->svms.restore_work);
3108 
3109 	/* Ensure list work is finished before process is destroyed */
3110 	flush_work(&p->svms.deferred_list_work);
3111 
3112 	/*
3113 	 * Ensure no retry fault comes in afterwards, as page fault handler will
3114 	 * not find kfd process and take mm lock to recover fault.
3115 	 */
3116 	atomic_inc(&p->svms.drain_pagefaults);
3117 	svm_range_drain_retry_fault(&p->svms);
3118 
3119 	list_for_each_entry_safe(prange, next, &p->svms.list, list) {
3120 		svm_range_unlink(prange);
3121 		svm_range_remove_notifier(prange);
3122 		svm_range_free(prange, true);
3123 	}
3124 
3125 	mutex_destroy(&p->svms.lock);
3126 
3127 	pr_debug("pasid 0x%x svms 0x%p done\n", p->pasid, &p->svms);
3128 }
3129 
3130 int svm_range_list_init(struct kfd_process *p)
3131 {
3132 	struct svm_range_list *svms = &p->svms;
3133 	int i;
3134 
3135 	svms->objects = RB_ROOT_CACHED;
3136 	mutex_init(&svms->lock);
3137 	INIT_LIST_HEAD(&svms->list);
3138 	atomic_set(&svms->evicted_ranges, 0);
3139 	atomic_set(&svms->drain_pagefaults, 0);
3140 	INIT_DELAYED_WORK(&svms->restore_work, svm_range_restore_work);
3141 	INIT_WORK(&svms->deferred_list_work, svm_range_deferred_list_work);
3142 	INIT_LIST_HEAD(&svms->deferred_range_list);
3143 	INIT_LIST_HEAD(&svms->criu_svm_metadata_list);
3144 	spin_lock_init(&svms->deferred_list_lock);
3145 
3146 	for (i = 0; i < p->n_pdds; i++)
3147 		if (KFD_IS_SVM_API_SUPPORTED(p->pdds[i]->dev->adev))
3148 			bitmap_set(svms->bitmap_supported, i, 1);
3149 
3150 	return 0;
3151 }
3152 
3153 /**
3154  * svm_range_check_vm - check if virtual address range mapped already
3155  * @p: current kfd_process
3156  * @start: range start address, in pages
3157  * @last: range last address, in pages
3158  * @bo_s: mapping start address in pages if address range already mapped
3159  * @bo_l: mapping last address in pages if address range already mapped
3160  *
3161  * The purpose is to avoid virtual address ranges already allocated by
3162  * kfd_ioctl_alloc_memory_of_gpu ioctl.
3163  * It looks for each pdd in the kfd_process.
3164  *
3165  * Context: Process context
3166  *
3167  * Return 0 - OK, if the range is not mapped.
3168  * Otherwise error code:
3169  * -EADDRINUSE - if address is mapped already by kfd_ioctl_alloc_memory_of_gpu
3170  * -ERESTARTSYS - A wait for the buffer to become unreserved was interrupted by
3171  * a signal. Release all buffer reservations and return to user-space.
3172  */
3173 static int
3174 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
3175 		   uint64_t *bo_s, uint64_t *bo_l)
3176 {
3177 	struct amdgpu_bo_va_mapping *mapping;
3178 	struct interval_tree_node *node;
3179 	uint32_t i;
3180 	int r;
3181 
3182 	for (i = 0; i < p->n_pdds; i++) {
3183 		struct amdgpu_vm *vm;
3184 
3185 		if (!p->pdds[i]->drm_priv)
3186 			continue;
3187 
3188 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
3189 		r = amdgpu_bo_reserve(vm->root.bo, false);
3190 		if (r)
3191 			return r;
3192 
3193 		node = interval_tree_iter_first(&vm->va, start, last);
3194 		if (node) {
3195 			pr_debug("range [0x%llx 0x%llx] already TTM mapped\n",
3196 				 start, last);
3197 			mapping = container_of((struct rb_node *)node,
3198 					       struct amdgpu_bo_va_mapping, rb);
3199 			if (bo_s && bo_l) {
3200 				*bo_s = mapping->start;
3201 				*bo_l = mapping->last;
3202 			}
3203 			amdgpu_bo_unreserve(vm->root.bo);
3204 			return -EADDRINUSE;
3205 		}
3206 		amdgpu_bo_unreserve(vm->root.bo);
3207 	}
3208 
3209 	return 0;
3210 }
3211 
3212 /**
3213  * svm_range_is_valid - check if virtual address range is valid
3214  * @p: current kfd_process
3215  * @start: range start address, in pages
3216  * @size: range size, in pages
3217  *
3218  * Valid virtual address range means it belongs to one or more VMAs
3219  *
3220  * Context: Process context
3221  *
3222  * Return:
3223  *  0 - OK, otherwise error code
3224  */
3225 static int
3226 svm_range_is_valid(struct kfd_process *p, uint64_t start, uint64_t size)
3227 {
3228 	const unsigned long device_vma = VM_IO | VM_PFNMAP | VM_MIXEDMAP;
3229 	struct vm_area_struct *vma;
3230 	unsigned long end;
3231 	unsigned long start_unchg = start;
3232 
3233 	start <<= PAGE_SHIFT;
3234 	end = start + (size << PAGE_SHIFT);
3235 	do {
3236 		vma = vma_lookup(p->mm, start);
3237 		if (!vma || (vma->vm_flags & device_vma))
3238 			return -EFAULT;
3239 		start = min(end, vma->vm_end);
3240 	} while (start < end);
3241 
3242 	return svm_range_check_vm(p, start_unchg, (end - 1) >> PAGE_SHIFT, NULL,
3243 				  NULL);
3244 }
3245 
3246 /**
3247  * svm_range_best_prefetch_location - decide the best prefetch location
3248  * @prange: svm range structure
3249  *
3250  * For xnack off:
3251  * If range map to single GPU, the best prefetch location is prefetch_loc, which
3252  * can be CPU or GPU.
3253  *
3254  * If range is ACCESS or ACCESS_IN_PLACE by mGPUs, only if mGPU connection on
3255  * XGMI same hive, the best prefetch location is prefetch_loc GPU, othervise
3256  * the best prefetch location is always CPU, because GPU can not have coherent
3257  * mapping VRAM of other GPUs even with large-BAR PCIe connection.
3258  *
3259  * For xnack on:
3260  * If range is not ACCESS_IN_PLACE by mGPUs, the best prefetch location is
3261  * prefetch_loc, other GPU access will generate vm fault and trigger migration.
3262  *
3263  * If range is ACCESS_IN_PLACE by mGPUs, only if mGPU connection on XGMI same
3264  * hive, the best prefetch location is prefetch_loc GPU, otherwise the best
3265  * prefetch location is always CPU.
3266  *
3267  * Context: Process context
3268  *
3269  * Return:
3270  * 0 for CPU or GPU id
3271  */
3272 static uint32_t
3273 svm_range_best_prefetch_location(struct svm_range *prange)
3274 {
3275 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
3276 	uint32_t best_loc = prange->prefetch_loc;
3277 	struct kfd_process_device *pdd;
3278 	struct kfd_node *bo_node;
3279 	struct kfd_process *p;
3280 	uint32_t gpuidx;
3281 
3282 	p = container_of(prange->svms, struct kfd_process, svms);
3283 
3284 	if (!best_loc || best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED)
3285 		goto out;
3286 
3287 	bo_node = svm_range_get_node_by_id(prange, best_loc);
3288 	if (!bo_node) {
3289 		WARN_ONCE(1, "failed to get valid kfd node at id%x\n", best_loc);
3290 		best_loc = 0;
3291 		goto out;
3292 	}
3293 
3294 	if (bo_node->adev->gmc.is_app_apu) {
3295 		best_loc = 0;
3296 		goto out;
3297 	}
3298 
3299 	if (p->xnack_enabled)
3300 		bitmap_copy(bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
3301 	else
3302 		bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
3303 			  MAX_GPU_INSTANCE);
3304 
3305 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
3306 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
3307 		if (!pdd) {
3308 			pr_debug("failed to get device by idx 0x%x\n", gpuidx);
3309 			continue;
3310 		}
3311 
3312 		if (pdd->dev->adev == bo_node->adev)
3313 			continue;
3314 
3315 		if (!svm_nodes_in_same_hive(pdd->dev, bo_node)) {
3316 			best_loc = 0;
3317 			break;
3318 		}
3319 	}
3320 
3321 out:
3322 	pr_debug("xnack %d svms 0x%p [0x%lx 0x%lx] best loc 0x%x\n",
3323 		 p->xnack_enabled, &p->svms, prange->start, prange->last,
3324 		 best_loc);
3325 
3326 	return best_loc;
3327 }
3328 
3329 /* svm_range_trigger_migration - start page migration if prefetch loc changed
3330  * @mm: current process mm_struct
3331  * @prange: svm range structure
3332  * @migrated: output, true if migration is triggered
3333  *
3334  * If range perfetch_loc is GPU, actual loc is cpu 0, then migrate the range
3335  * from ram to vram.
3336  * If range prefetch_loc is cpu 0, actual loc is GPU, then migrate the range
3337  * from vram to ram.
3338  *
3339  * If GPU vm fault retry is not enabled, migration interact with MMU notifier
3340  * and restore work:
3341  * 1. migrate_vma_setup invalidate pages, MMU notifier callback svm_range_evict
3342  *    stops all queues, schedule restore work
3343  * 2. svm_range_restore_work wait for migration is done by
3344  *    a. svm_range_validate_vram takes prange->migrate_mutex
3345  *    b. svm_range_validate_ram HMM get pages wait for CPU fault handle returns
3346  * 3. restore work update mappings of GPU, resume all queues.
3347  *
3348  * Context: Process context
3349  *
3350  * Return:
3351  * 0 - OK, otherwise - error code of migration
3352  */
3353 static int
3354 svm_range_trigger_migration(struct mm_struct *mm, struct svm_range *prange,
3355 			    bool *migrated)
3356 {
3357 	uint32_t best_loc;
3358 	int r = 0;
3359 
3360 	*migrated = false;
3361 	best_loc = svm_range_best_prefetch_location(prange);
3362 
3363 	if (best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3364 	    best_loc == prange->actual_loc)
3365 		return 0;
3366 
3367 	if (!best_loc) {
3368 		r = svm_migrate_vram_to_ram(prange, mm,
3369 					KFD_MIGRATE_TRIGGER_PREFETCH, NULL);
3370 		*migrated = !r;
3371 		return r;
3372 	}
3373 
3374 	r = svm_migrate_to_vram(prange, best_loc, mm, KFD_MIGRATE_TRIGGER_PREFETCH);
3375 	*migrated = !r;
3376 
3377 	return r;
3378 }
3379 
3380 int svm_range_schedule_evict_svm_bo(struct amdgpu_amdkfd_fence *fence)
3381 {
3382 	if (!fence)
3383 		return -EINVAL;
3384 
3385 	if (dma_fence_is_signaled(&fence->base))
3386 		return 0;
3387 
3388 	if (fence->svm_bo) {
3389 		WRITE_ONCE(fence->svm_bo->evicting, 1);
3390 		schedule_work(&fence->svm_bo->eviction_work);
3391 	}
3392 
3393 	return 0;
3394 }
3395 
3396 static void svm_range_evict_svm_bo_worker(struct work_struct *work)
3397 {
3398 	struct svm_range_bo *svm_bo;
3399 	struct mm_struct *mm;
3400 	int r = 0;
3401 
3402 	svm_bo = container_of(work, struct svm_range_bo, eviction_work);
3403 	if (!svm_bo_ref_unless_zero(svm_bo))
3404 		return; /* svm_bo was freed while eviction was pending */
3405 
3406 	if (mmget_not_zero(svm_bo->eviction_fence->mm)) {
3407 		mm = svm_bo->eviction_fence->mm;
3408 	} else {
3409 		svm_range_bo_unref(svm_bo);
3410 		return;
3411 	}
3412 
3413 	mmap_read_lock(mm);
3414 	spin_lock(&svm_bo->list_lock);
3415 	while (!list_empty(&svm_bo->range_list) && !r) {
3416 		struct svm_range *prange =
3417 				list_first_entry(&svm_bo->range_list,
3418 						struct svm_range, svm_bo_list);
3419 		int retries = 3;
3420 
3421 		list_del_init(&prange->svm_bo_list);
3422 		spin_unlock(&svm_bo->list_lock);
3423 
3424 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
3425 			 prange->start, prange->last);
3426 
3427 		mutex_lock(&prange->migrate_mutex);
3428 		do {
3429 			r = svm_migrate_vram_to_ram(prange, mm,
3430 					KFD_MIGRATE_TRIGGER_TTM_EVICTION, NULL);
3431 		} while (!r && prange->actual_loc && --retries);
3432 
3433 		if (!r && prange->actual_loc)
3434 			pr_info_once("Migration failed during eviction");
3435 
3436 		if (!prange->actual_loc) {
3437 			mutex_lock(&prange->lock);
3438 			prange->svm_bo = NULL;
3439 			mutex_unlock(&prange->lock);
3440 		}
3441 		mutex_unlock(&prange->migrate_mutex);
3442 
3443 		spin_lock(&svm_bo->list_lock);
3444 	}
3445 	spin_unlock(&svm_bo->list_lock);
3446 	mmap_read_unlock(mm);
3447 	mmput(mm);
3448 
3449 	dma_fence_signal(&svm_bo->eviction_fence->base);
3450 
3451 	/* This is the last reference to svm_bo, after svm_range_vram_node_free
3452 	 * has been called in svm_migrate_vram_to_ram
3453 	 */
3454 	WARN_ONCE(!r && kref_read(&svm_bo->kref) != 1, "This was not the last reference\n");
3455 	svm_range_bo_unref(svm_bo);
3456 }
3457 
3458 static int
3459 svm_range_set_attr(struct kfd_process *p, struct mm_struct *mm,
3460 		   uint64_t start, uint64_t size, uint32_t nattr,
3461 		   struct kfd_ioctl_svm_attribute *attrs)
3462 {
3463 	struct amdkfd_process_info *process_info = p->kgd_process_info;
3464 	struct list_head update_list;
3465 	struct list_head insert_list;
3466 	struct list_head remove_list;
3467 	struct svm_range_list *svms;
3468 	struct svm_range *prange;
3469 	struct svm_range *next;
3470 	bool update_mapping = false;
3471 	bool flush_tlb;
3472 	int r = 0;
3473 
3474 	pr_debug("pasid 0x%x svms 0x%p [0x%llx 0x%llx] pages 0x%llx\n",
3475 		 p->pasid, &p->svms, start, start + size - 1, size);
3476 
3477 	r = svm_range_check_attr(p, nattr, attrs);
3478 	if (r)
3479 		return r;
3480 
3481 	svms = &p->svms;
3482 
3483 	mutex_lock(&process_info->lock);
3484 
3485 	svm_range_list_lock_and_flush_work(svms, mm);
3486 
3487 	r = svm_range_is_valid(p, start, size);
3488 	if (r) {
3489 		pr_debug("invalid range r=%d\n", r);
3490 		mmap_write_unlock(mm);
3491 		goto out;
3492 	}
3493 
3494 	mutex_lock(&svms->lock);
3495 
3496 	/* Add new range and split existing ranges as needed */
3497 	r = svm_range_add(p, start, size, nattr, attrs, &update_list,
3498 			  &insert_list, &remove_list);
3499 	if (r) {
3500 		mutex_unlock(&svms->lock);
3501 		mmap_write_unlock(mm);
3502 		goto out;
3503 	}
3504 	/* Apply changes as a transaction */
3505 	list_for_each_entry_safe(prange, next, &insert_list, list) {
3506 		svm_range_add_to_svms(prange);
3507 		svm_range_add_notifier_locked(mm, prange);
3508 	}
3509 	list_for_each_entry(prange, &update_list, update_list) {
3510 		svm_range_apply_attrs(p, prange, nattr, attrs, &update_mapping);
3511 		/* TODO: unmap ranges from GPU that lost access */
3512 	}
3513 	list_for_each_entry_safe(prange, next, &remove_list, update_list) {
3514 		pr_debug("unlink old 0x%p prange 0x%p [0x%lx 0x%lx]\n",
3515 			 prange->svms, prange, prange->start,
3516 			 prange->last);
3517 		svm_range_unlink(prange);
3518 		svm_range_remove_notifier(prange);
3519 		svm_range_free(prange, false);
3520 	}
3521 
3522 	mmap_write_downgrade(mm);
3523 	/* Trigger migrations and revalidate and map to GPUs as needed. If
3524 	 * this fails we may be left with partially completed actions. There
3525 	 * is no clean way of rolling back to the previous state in such a
3526 	 * case because the rollback wouldn't be guaranteed to work either.
3527 	 */
3528 	list_for_each_entry(prange, &update_list, update_list) {
3529 		bool migrated;
3530 
3531 		mutex_lock(&prange->migrate_mutex);
3532 
3533 		r = svm_range_trigger_migration(mm, prange, &migrated);
3534 		if (r)
3535 			goto out_unlock_range;
3536 
3537 		if (migrated && (!p->xnack_enabled ||
3538 		    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) &&
3539 		    prange->mapped_to_gpu) {
3540 			pr_debug("restore_work will update mappings of GPUs\n");
3541 			mutex_unlock(&prange->migrate_mutex);
3542 			continue;
3543 		}
3544 
3545 		if (!migrated && !update_mapping) {
3546 			mutex_unlock(&prange->migrate_mutex);
3547 			continue;
3548 		}
3549 
3550 		flush_tlb = !migrated && update_mapping && prange->mapped_to_gpu;
3551 
3552 		r = svm_range_validate_and_map(mm, prange, MAX_GPU_INSTANCE,
3553 					       true, true, flush_tlb);
3554 		if (r)
3555 			pr_debug("failed %d to map svm range\n", r);
3556 
3557 out_unlock_range:
3558 		mutex_unlock(&prange->migrate_mutex);
3559 		if (r)
3560 			break;
3561 	}
3562 
3563 	svm_range_debug_dump(svms);
3564 
3565 	mutex_unlock(&svms->lock);
3566 	mmap_read_unlock(mm);
3567 out:
3568 	mutex_unlock(&process_info->lock);
3569 
3570 	pr_debug("pasid 0x%x svms 0x%p [0x%llx 0x%llx] done, r=%d\n", p->pasid,
3571 		 &p->svms, start, start + size - 1, r);
3572 
3573 	return r;
3574 }
3575 
3576 static int
3577 svm_range_get_attr(struct kfd_process *p, struct mm_struct *mm,
3578 		   uint64_t start, uint64_t size, uint32_t nattr,
3579 		   struct kfd_ioctl_svm_attribute *attrs)
3580 {
3581 	DECLARE_BITMAP(bitmap_access, MAX_GPU_INSTANCE);
3582 	DECLARE_BITMAP(bitmap_aip, MAX_GPU_INSTANCE);
3583 	bool get_preferred_loc = false;
3584 	bool get_prefetch_loc = false;
3585 	bool get_granularity = false;
3586 	bool get_accessible = false;
3587 	bool get_flags = false;
3588 	uint64_t last = start + size - 1UL;
3589 	uint8_t granularity = 0xff;
3590 	struct interval_tree_node *node;
3591 	struct svm_range_list *svms;
3592 	struct svm_range *prange;
3593 	uint32_t prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3594 	uint32_t location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3595 	uint32_t flags_and = 0xffffffff;
3596 	uint32_t flags_or = 0;
3597 	int gpuidx;
3598 	uint32_t i;
3599 	int r = 0;
3600 
3601 	pr_debug("svms 0x%p [0x%llx 0x%llx] nattr 0x%x\n", &p->svms, start,
3602 		 start + size - 1, nattr);
3603 
3604 	/* Flush pending deferred work to avoid racing with deferred actions from
3605 	 * previous memory map changes (e.g. munmap). Concurrent memory map changes
3606 	 * can still race with get_attr because we don't hold the mmap lock. But that
3607 	 * would be a race condition in the application anyway, and undefined
3608 	 * behaviour is acceptable in that case.
3609 	 */
3610 	flush_work(&p->svms.deferred_list_work);
3611 
3612 	mmap_read_lock(mm);
3613 	r = svm_range_is_valid(p, start, size);
3614 	mmap_read_unlock(mm);
3615 	if (r) {
3616 		pr_debug("invalid range r=%d\n", r);
3617 		return r;
3618 	}
3619 
3620 	for (i = 0; i < nattr; i++) {
3621 		switch (attrs[i].type) {
3622 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3623 			get_preferred_loc = true;
3624 			break;
3625 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3626 			get_prefetch_loc = true;
3627 			break;
3628 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3629 			get_accessible = true;
3630 			break;
3631 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3632 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3633 			get_flags = true;
3634 			break;
3635 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3636 			get_granularity = true;
3637 			break;
3638 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
3639 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
3640 			fallthrough;
3641 		default:
3642 			pr_debug("get invalid attr type 0x%x\n", attrs[i].type);
3643 			return -EINVAL;
3644 		}
3645 	}
3646 
3647 	svms = &p->svms;
3648 
3649 	mutex_lock(&svms->lock);
3650 
3651 	node = interval_tree_iter_first(&svms->objects, start, last);
3652 	if (!node) {
3653 		pr_debug("range attrs not found return default values\n");
3654 		svm_range_set_default_attributes(&location, &prefetch_loc,
3655 						 &granularity, &flags_and);
3656 		flags_or = flags_and;
3657 		if (p->xnack_enabled)
3658 			bitmap_copy(bitmap_access, svms->bitmap_supported,
3659 				    MAX_GPU_INSTANCE);
3660 		else
3661 			bitmap_zero(bitmap_access, MAX_GPU_INSTANCE);
3662 		bitmap_zero(bitmap_aip, MAX_GPU_INSTANCE);
3663 		goto fill_values;
3664 	}
3665 	bitmap_copy(bitmap_access, svms->bitmap_supported, MAX_GPU_INSTANCE);
3666 	bitmap_copy(bitmap_aip, svms->bitmap_supported, MAX_GPU_INSTANCE);
3667 
3668 	while (node) {
3669 		struct interval_tree_node *next;
3670 
3671 		prange = container_of(node, struct svm_range, it_node);
3672 		next = interval_tree_iter_next(node, start, last);
3673 
3674 		if (get_preferred_loc) {
3675 			if (prange->preferred_loc ==
3676 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3677 			    (location != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3678 			     location != prange->preferred_loc)) {
3679 				location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3680 				get_preferred_loc = false;
3681 			} else {
3682 				location = prange->preferred_loc;
3683 			}
3684 		}
3685 		if (get_prefetch_loc) {
3686 			if (prange->prefetch_loc ==
3687 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3688 			    (prefetch_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3689 			     prefetch_loc != prange->prefetch_loc)) {
3690 				prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3691 				get_prefetch_loc = false;
3692 			} else {
3693 				prefetch_loc = prange->prefetch_loc;
3694 			}
3695 		}
3696 		if (get_accessible) {
3697 			bitmap_and(bitmap_access, bitmap_access,
3698 				   prange->bitmap_access, MAX_GPU_INSTANCE);
3699 			bitmap_and(bitmap_aip, bitmap_aip,
3700 				   prange->bitmap_aip, MAX_GPU_INSTANCE);
3701 		}
3702 		if (get_flags) {
3703 			flags_and &= prange->flags;
3704 			flags_or |= prange->flags;
3705 		}
3706 
3707 		if (get_granularity && prange->granularity < granularity)
3708 			granularity = prange->granularity;
3709 
3710 		node = next;
3711 	}
3712 fill_values:
3713 	mutex_unlock(&svms->lock);
3714 
3715 	for (i = 0; i < nattr; i++) {
3716 		switch (attrs[i].type) {
3717 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3718 			attrs[i].value = location;
3719 			break;
3720 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3721 			attrs[i].value = prefetch_loc;
3722 			break;
3723 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3724 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
3725 							       attrs[i].value);
3726 			if (gpuidx < 0) {
3727 				pr_debug("invalid gpuid %x\n", attrs[i].value);
3728 				return -EINVAL;
3729 			}
3730 			if (test_bit(gpuidx, bitmap_access))
3731 				attrs[i].type = KFD_IOCTL_SVM_ATTR_ACCESS;
3732 			else if (test_bit(gpuidx, bitmap_aip))
3733 				attrs[i].type =
3734 					KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE;
3735 			else
3736 				attrs[i].type = KFD_IOCTL_SVM_ATTR_NO_ACCESS;
3737 			break;
3738 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3739 			attrs[i].value = flags_and;
3740 			break;
3741 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3742 			attrs[i].value = ~flags_or;
3743 			break;
3744 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3745 			attrs[i].value = (uint32_t)granularity;
3746 			break;
3747 		}
3748 	}
3749 
3750 	return 0;
3751 }
3752 
3753 int kfd_criu_resume_svm(struct kfd_process *p)
3754 {
3755 	struct kfd_ioctl_svm_attribute *set_attr_new, *set_attr = NULL;
3756 	int nattr_common = 4, nattr_accessibility = 1;
3757 	struct criu_svm_metadata *criu_svm_md = NULL;
3758 	struct svm_range_list *svms = &p->svms;
3759 	struct criu_svm_metadata *next = NULL;
3760 	uint32_t set_flags = 0xffffffff;
3761 	int i, j, num_attrs, ret = 0;
3762 	uint64_t set_attr_size;
3763 	struct mm_struct *mm;
3764 
3765 	if (list_empty(&svms->criu_svm_metadata_list)) {
3766 		pr_debug("No SVM data from CRIU restore stage 2\n");
3767 		return ret;
3768 	}
3769 
3770 	mm = get_task_mm(p->lead_thread);
3771 	if (!mm) {
3772 		pr_err("failed to get mm for the target process\n");
3773 		return -ESRCH;
3774 	}
3775 
3776 	num_attrs = nattr_common + (nattr_accessibility * p->n_pdds);
3777 
3778 	i = j = 0;
3779 	list_for_each_entry(criu_svm_md, &svms->criu_svm_metadata_list, list) {
3780 		pr_debug("criu_svm_md[%d]\n\tstart: 0x%llx size: 0x%llx (npages)\n",
3781 			 i, criu_svm_md->data.start_addr, criu_svm_md->data.size);
3782 
3783 		for (j = 0; j < num_attrs; j++) {
3784 			pr_debug("\ncriu_svm_md[%d]->attrs[%d].type : 0x%x\ncriu_svm_md[%d]->attrs[%d].value : 0x%x\n",
3785 				 i, j, criu_svm_md->data.attrs[j].type,
3786 				 i, j, criu_svm_md->data.attrs[j].value);
3787 			switch (criu_svm_md->data.attrs[j].type) {
3788 			/* During Checkpoint operation, the query for
3789 			 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC attribute might
3790 			 * return KFD_IOCTL_SVM_LOCATION_UNDEFINED if they were
3791 			 * not used by the range which was checkpointed. Care
3792 			 * must be taken to not restore with an invalid value
3793 			 * otherwise the gpuidx value will be invalid and
3794 			 * set_attr would eventually fail so just replace those
3795 			 * with another dummy attribute such as
3796 			 * KFD_IOCTL_SVM_ATTR_SET_FLAGS.
3797 			 */
3798 			case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3799 				if (criu_svm_md->data.attrs[j].value ==
3800 				    KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
3801 					criu_svm_md->data.attrs[j].type =
3802 						KFD_IOCTL_SVM_ATTR_SET_FLAGS;
3803 					criu_svm_md->data.attrs[j].value = 0;
3804 				}
3805 				break;
3806 			case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3807 				set_flags = criu_svm_md->data.attrs[j].value;
3808 				break;
3809 			default:
3810 				break;
3811 			}
3812 		}
3813 
3814 		/* CLR_FLAGS is not available via get_attr during checkpoint but
3815 		 * it needs to be inserted before restoring the ranges so
3816 		 * allocate extra space for it before calling set_attr
3817 		 */
3818 		set_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
3819 						(num_attrs + 1);
3820 		set_attr_new = krealloc(set_attr, set_attr_size,
3821 					    GFP_KERNEL);
3822 		if (!set_attr_new) {
3823 			ret = -ENOMEM;
3824 			goto exit;
3825 		}
3826 		set_attr = set_attr_new;
3827 
3828 		memcpy(set_attr, criu_svm_md->data.attrs, num_attrs *
3829 					sizeof(struct kfd_ioctl_svm_attribute));
3830 		set_attr[num_attrs].type = KFD_IOCTL_SVM_ATTR_CLR_FLAGS;
3831 		set_attr[num_attrs].value = ~set_flags;
3832 
3833 		ret = svm_range_set_attr(p, mm, criu_svm_md->data.start_addr,
3834 					 criu_svm_md->data.size, num_attrs + 1,
3835 					 set_attr);
3836 		if (ret) {
3837 			pr_err("CRIU: failed to set range attributes\n");
3838 			goto exit;
3839 		}
3840 
3841 		i++;
3842 	}
3843 exit:
3844 	kfree(set_attr);
3845 	list_for_each_entry_safe(criu_svm_md, next, &svms->criu_svm_metadata_list, list) {
3846 		pr_debug("freeing criu_svm_md[]\n\tstart: 0x%llx\n",
3847 						criu_svm_md->data.start_addr);
3848 		kfree(criu_svm_md);
3849 	}
3850 
3851 	mmput(mm);
3852 	return ret;
3853 
3854 }
3855 
3856 int kfd_criu_restore_svm(struct kfd_process *p,
3857 			 uint8_t __user *user_priv_ptr,
3858 			 uint64_t *priv_data_offset,
3859 			 uint64_t max_priv_data_size)
3860 {
3861 	uint64_t svm_priv_data_size, svm_object_md_size, svm_attrs_size;
3862 	int nattr_common = 4, nattr_accessibility = 1;
3863 	struct criu_svm_metadata *criu_svm_md = NULL;
3864 	struct svm_range_list *svms = &p->svms;
3865 	uint32_t num_devices;
3866 	int ret = 0;
3867 
3868 	num_devices = p->n_pdds;
3869 	/* Handle one SVM range object at a time, also the number of gpus are
3870 	 * assumed to be same on the restore node, checking must be done while
3871 	 * evaluating the topology earlier
3872 	 */
3873 
3874 	svm_attrs_size = sizeof(struct kfd_ioctl_svm_attribute) *
3875 		(nattr_common + nattr_accessibility * num_devices);
3876 	svm_object_md_size = sizeof(struct criu_svm_metadata) + svm_attrs_size;
3877 
3878 	svm_priv_data_size = sizeof(struct kfd_criu_svm_range_priv_data) +
3879 								svm_attrs_size;
3880 
3881 	criu_svm_md = kzalloc(svm_object_md_size, GFP_KERNEL);
3882 	if (!criu_svm_md) {
3883 		pr_err("failed to allocate memory to store svm metadata\n");
3884 		return -ENOMEM;
3885 	}
3886 	if (*priv_data_offset + svm_priv_data_size > max_priv_data_size) {
3887 		ret = -EINVAL;
3888 		goto exit;
3889 	}
3890 
3891 	ret = copy_from_user(&criu_svm_md->data, user_priv_ptr + *priv_data_offset,
3892 			     svm_priv_data_size);
3893 	if (ret) {
3894 		ret = -EFAULT;
3895 		goto exit;
3896 	}
3897 	*priv_data_offset += svm_priv_data_size;
3898 
3899 	list_add_tail(&criu_svm_md->list, &svms->criu_svm_metadata_list);
3900 
3901 	return 0;
3902 
3903 
3904 exit:
3905 	kfree(criu_svm_md);
3906 	return ret;
3907 }
3908 
3909 int svm_range_get_info(struct kfd_process *p, uint32_t *num_svm_ranges,
3910 		       uint64_t *svm_priv_data_size)
3911 {
3912 	uint64_t total_size, accessibility_size, common_attr_size;
3913 	int nattr_common = 4, nattr_accessibility = 1;
3914 	int num_devices = p->n_pdds;
3915 	struct svm_range_list *svms;
3916 	struct svm_range *prange;
3917 	uint32_t count = 0;
3918 
3919 	*svm_priv_data_size = 0;
3920 
3921 	svms = &p->svms;
3922 	if (!svms)
3923 		return -EINVAL;
3924 
3925 	mutex_lock(&svms->lock);
3926 	list_for_each_entry(prange, &svms->list, list) {
3927 		pr_debug("prange: 0x%p start: 0x%lx\t npages: 0x%llx\t end: 0x%llx\n",
3928 			 prange, prange->start, prange->npages,
3929 			 prange->start + prange->npages - 1);
3930 		count++;
3931 	}
3932 	mutex_unlock(&svms->lock);
3933 
3934 	*num_svm_ranges = count;
3935 	/* Only the accessbility attributes need to be queried for all the gpus
3936 	 * individually, remaining ones are spanned across the entire process
3937 	 * regardless of the various gpu nodes. Of the remaining attributes,
3938 	 * KFD_IOCTL_SVM_ATTR_CLR_FLAGS need not be saved.
3939 	 *
3940 	 * KFD_IOCTL_SVM_ATTR_PREFERRED_LOC
3941 	 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC
3942 	 * KFD_IOCTL_SVM_ATTR_SET_FLAGS
3943 	 * KFD_IOCTL_SVM_ATTR_GRANULARITY
3944 	 *
3945 	 * ** ACCESSBILITY ATTRIBUTES **
3946 	 * (Considered as one, type is altered during query, value is gpuid)
3947 	 * KFD_IOCTL_SVM_ATTR_ACCESS
3948 	 * KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE
3949 	 * KFD_IOCTL_SVM_ATTR_NO_ACCESS
3950 	 */
3951 	if (*num_svm_ranges > 0) {
3952 		common_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
3953 			nattr_common;
3954 		accessibility_size = sizeof(struct kfd_ioctl_svm_attribute) *
3955 			nattr_accessibility * num_devices;
3956 
3957 		total_size = sizeof(struct kfd_criu_svm_range_priv_data) +
3958 			common_attr_size + accessibility_size;
3959 
3960 		*svm_priv_data_size = *num_svm_ranges * total_size;
3961 	}
3962 
3963 	pr_debug("num_svm_ranges %u total_priv_size %llu\n", *num_svm_ranges,
3964 		 *svm_priv_data_size);
3965 	return 0;
3966 }
3967 
3968 int kfd_criu_checkpoint_svm(struct kfd_process *p,
3969 			    uint8_t __user *user_priv_data,
3970 			    uint64_t *priv_data_offset)
3971 {
3972 	struct kfd_criu_svm_range_priv_data *svm_priv = NULL;
3973 	struct kfd_ioctl_svm_attribute *query_attr = NULL;
3974 	uint64_t svm_priv_data_size, query_attr_size = 0;
3975 	int index, nattr_common = 4, ret = 0;
3976 	struct svm_range_list *svms;
3977 	int num_devices = p->n_pdds;
3978 	struct svm_range *prange;
3979 	struct mm_struct *mm;
3980 
3981 	svms = &p->svms;
3982 	if (!svms)
3983 		return -EINVAL;
3984 
3985 	mm = get_task_mm(p->lead_thread);
3986 	if (!mm) {
3987 		pr_err("failed to get mm for the target process\n");
3988 		return -ESRCH;
3989 	}
3990 
3991 	query_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
3992 				(nattr_common + num_devices);
3993 
3994 	query_attr = kzalloc(query_attr_size, GFP_KERNEL);
3995 	if (!query_attr) {
3996 		ret = -ENOMEM;
3997 		goto exit;
3998 	}
3999 
4000 	query_attr[0].type = KFD_IOCTL_SVM_ATTR_PREFERRED_LOC;
4001 	query_attr[1].type = KFD_IOCTL_SVM_ATTR_PREFETCH_LOC;
4002 	query_attr[2].type = KFD_IOCTL_SVM_ATTR_SET_FLAGS;
4003 	query_attr[3].type = KFD_IOCTL_SVM_ATTR_GRANULARITY;
4004 
4005 	for (index = 0; index < num_devices; index++) {
4006 		struct kfd_process_device *pdd = p->pdds[index];
4007 
4008 		query_attr[index + nattr_common].type =
4009 			KFD_IOCTL_SVM_ATTR_ACCESS;
4010 		query_attr[index + nattr_common].value = pdd->user_gpu_id;
4011 	}
4012 
4013 	svm_priv_data_size = sizeof(*svm_priv) + query_attr_size;
4014 
4015 	svm_priv = kzalloc(svm_priv_data_size, GFP_KERNEL);
4016 	if (!svm_priv) {
4017 		ret = -ENOMEM;
4018 		goto exit_query;
4019 	}
4020 
4021 	index = 0;
4022 	list_for_each_entry(prange, &svms->list, list) {
4023 
4024 		svm_priv->object_type = KFD_CRIU_OBJECT_TYPE_SVM_RANGE;
4025 		svm_priv->start_addr = prange->start;
4026 		svm_priv->size = prange->npages;
4027 		memcpy(&svm_priv->attrs, query_attr, query_attr_size);
4028 		pr_debug("CRIU: prange: 0x%p start: 0x%lx\t npages: 0x%llx end: 0x%llx\t size: 0x%llx\n",
4029 			 prange, prange->start, prange->npages,
4030 			 prange->start + prange->npages - 1,
4031 			 prange->npages * PAGE_SIZE);
4032 
4033 		ret = svm_range_get_attr(p, mm, svm_priv->start_addr,
4034 					 svm_priv->size,
4035 					 (nattr_common + num_devices),
4036 					 svm_priv->attrs);
4037 		if (ret) {
4038 			pr_err("CRIU: failed to obtain range attributes\n");
4039 			goto exit_priv;
4040 		}
4041 
4042 		if (copy_to_user(user_priv_data + *priv_data_offset, svm_priv,
4043 				 svm_priv_data_size)) {
4044 			pr_err("Failed to copy svm priv to user\n");
4045 			ret = -EFAULT;
4046 			goto exit_priv;
4047 		}
4048 
4049 		*priv_data_offset += svm_priv_data_size;
4050 
4051 	}
4052 
4053 
4054 exit_priv:
4055 	kfree(svm_priv);
4056 exit_query:
4057 	kfree(query_attr);
4058 exit:
4059 	mmput(mm);
4060 	return ret;
4061 }
4062 
4063 int
4064 svm_ioctl(struct kfd_process *p, enum kfd_ioctl_svm_op op, uint64_t start,
4065 	  uint64_t size, uint32_t nattrs, struct kfd_ioctl_svm_attribute *attrs)
4066 {
4067 	struct mm_struct *mm = current->mm;
4068 	int r;
4069 
4070 	start >>= PAGE_SHIFT;
4071 	size >>= PAGE_SHIFT;
4072 
4073 	switch (op) {
4074 	case KFD_IOCTL_SVM_OP_SET_ATTR:
4075 		r = svm_range_set_attr(p, mm, start, size, nattrs, attrs);
4076 		break;
4077 	case KFD_IOCTL_SVM_OP_GET_ATTR:
4078 		r = svm_range_get_attr(p, mm, start, size, nattrs, attrs);
4079 		break;
4080 	default:
4081 		r = EINVAL;
4082 		break;
4083 	}
4084 
4085 	return r;
4086 }
4087