xref: /openbmc/linux/drivers/gpu/drm/amd/amdkfd/kfd_svm.c (revision f77d1a49)
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 #define dynamic_svm_range_dump(svms) \
52 	_dynamic_func_call_no_desc("svm_range_dump", svm_range_debug_dump, svms)
53 
54 /* Giant svm range split into smaller ranges based on this, it is decided using
55  * minimum of all dGPU/APU 1/32 VRAM size, between 2MB to 1GB and alignment to
56  * power of 2MB.
57  */
58 static uint64_t max_svm_range_pages;
59 
60 struct criu_svm_metadata {
61 	struct list_head list;
62 	struct kfd_criu_svm_range_priv_data data;
63 };
64 
65 static void svm_range_evict_svm_bo_worker(struct work_struct *work);
66 static bool
67 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
68 				    const struct mmu_notifier_range *range,
69 				    unsigned long cur_seq);
70 static int
71 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
72 		   uint64_t *bo_s, uint64_t *bo_l);
73 static const struct mmu_interval_notifier_ops svm_range_mn_ops = {
74 	.invalidate = svm_range_cpu_invalidate_pagetables,
75 };
76 
77 /**
78  * svm_range_unlink - unlink svm_range from lists and interval tree
79  * @prange: svm range structure to be removed
80  *
81  * Remove the svm_range from the svms and svm_bo lists and the svms
82  * interval tree.
83  *
84  * Context: The caller must hold svms->lock
85  */
86 static void svm_range_unlink(struct svm_range *prange)
87 {
88 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
89 		 prange, prange->start, prange->last);
90 
91 	if (prange->svm_bo) {
92 		spin_lock(&prange->svm_bo->list_lock);
93 		list_del(&prange->svm_bo_list);
94 		spin_unlock(&prange->svm_bo->list_lock);
95 	}
96 
97 	list_del(&prange->list);
98 	if (prange->it_node.start != 0 && prange->it_node.last != 0)
99 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
100 }
101 
102 static void
103 svm_range_add_notifier_locked(struct mm_struct *mm, struct svm_range *prange)
104 {
105 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
106 		 prange, prange->start, prange->last);
107 
108 	mmu_interval_notifier_insert_locked(&prange->notifier, mm,
109 				     prange->start << PAGE_SHIFT,
110 				     prange->npages << PAGE_SHIFT,
111 				     &svm_range_mn_ops);
112 }
113 
114 /**
115  * svm_range_add_to_svms - add svm range to svms
116  * @prange: svm range structure to be added
117  *
118  * Add the svm range to svms interval tree and link list
119  *
120  * Context: The caller must hold svms->lock
121  */
122 static void svm_range_add_to_svms(struct svm_range *prange)
123 {
124 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
125 		 prange, prange->start, prange->last);
126 
127 	list_move_tail(&prange->list, &prange->svms->list);
128 	prange->it_node.start = prange->start;
129 	prange->it_node.last = prange->last;
130 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
131 }
132 
133 static void svm_range_remove_notifier(struct svm_range *prange)
134 {
135 	pr_debug("remove notifier svms 0x%p prange 0x%p [0x%lx 0x%lx]\n",
136 		 prange->svms, prange,
137 		 prange->notifier.interval_tree.start >> PAGE_SHIFT,
138 		 prange->notifier.interval_tree.last >> PAGE_SHIFT);
139 
140 	if (prange->notifier.interval_tree.start != 0 &&
141 	    prange->notifier.interval_tree.last != 0)
142 		mmu_interval_notifier_remove(&prange->notifier);
143 }
144 
145 static bool
146 svm_is_valid_dma_mapping_addr(struct device *dev, dma_addr_t dma_addr)
147 {
148 	return dma_addr && !dma_mapping_error(dev, dma_addr) &&
149 	       !(dma_addr & SVM_RANGE_VRAM_DOMAIN);
150 }
151 
152 static int
153 svm_range_dma_map_dev(struct amdgpu_device *adev, struct svm_range *prange,
154 		      unsigned long offset, unsigned long npages,
155 		      unsigned long *hmm_pfns, uint32_t gpuidx)
156 {
157 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
158 	dma_addr_t *addr = prange->dma_addr[gpuidx];
159 	struct device *dev = adev->dev;
160 	struct page *page;
161 	int i, r;
162 
163 	if (!addr) {
164 		addr = kvcalloc(prange->npages, sizeof(*addr), GFP_KERNEL);
165 		if (!addr)
166 			return -ENOMEM;
167 		prange->dma_addr[gpuidx] = addr;
168 	}
169 
170 	addr += offset;
171 	for (i = 0; i < npages; i++) {
172 		if (svm_is_valid_dma_mapping_addr(dev, addr[i]))
173 			dma_unmap_page(dev, addr[i], PAGE_SIZE, dir);
174 
175 		page = hmm_pfn_to_page(hmm_pfns[i]);
176 		if (is_zone_device_page(page)) {
177 			struct amdgpu_device *bo_adev = prange->svm_bo->node->adev;
178 
179 			addr[i] = (hmm_pfns[i] << PAGE_SHIFT) +
180 				   bo_adev->vm_manager.vram_base_offset -
181 				   bo_adev->kfd.pgmap.range.start;
182 			addr[i] |= SVM_RANGE_VRAM_DOMAIN;
183 			pr_debug_ratelimited("vram address: 0x%llx\n", addr[i]);
184 			continue;
185 		}
186 		addr[i] = dma_map_page(dev, page, 0, PAGE_SIZE, dir);
187 		r = dma_mapping_error(dev, addr[i]);
188 		if (r) {
189 			dev_err(dev, "failed %d dma_map_page\n", r);
190 			return r;
191 		}
192 		pr_debug_ratelimited("dma mapping 0x%llx for page addr 0x%lx\n",
193 				     addr[i] >> PAGE_SHIFT, page_to_pfn(page));
194 	}
195 	return 0;
196 }
197 
198 static int
199 svm_range_dma_map(struct svm_range *prange, unsigned long *bitmap,
200 		  unsigned long offset, unsigned long npages,
201 		  unsigned long *hmm_pfns)
202 {
203 	struct kfd_process *p;
204 	uint32_t gpuidx;
205 	int r;
206 
207 	p = container_of(prange->svms, struct kfd_process, svms);
208 
209 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
210 		struct kfd_process_device *pdd;
211 
212 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
213 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
214 		if (!pdd) {
215 			pr_debug("failed to find device idx %d\n", gpuidx);
216 			return -EINVAL;
217 		}
218 
219 		r = svm_range_dma_map_dev(pdd->dev->adev, prange, offset, npages,
220 					  hmm_pfns, gpuidx);
221 		if (r)
222 			break;
223 	}
224 
225 	return r;
226 }
227 
228 void svm_range_dma_unmap(struct device *dev, dma_addr_t *dma_addr,
229 			 unsigned long offset, unsigned long npages)
230 {
231 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
232 	int i;
233 
234 	if (!dma_addr)
235 		return;
236 
237 	for (i = offset; i < offset + npages; i++) {
238 		if (!svm_is_valid_dma_mapping_addr(dev, dma_addr[i]))
239 			continue;
240 		pr_debug_ratelimited("unmap 0x%llx\n", dma_addr[i] >> PAGE_SHIFT);
241 		dma_unmap_page(dev, dma_addr[i], PAGE_SIZE, dir);
242 		dma_addr[i] = 0;
243 	}
244 }
245 
246 void svm_range_free_dma_mappings(struct svm_range *prange, bool unmap_dma)
247 {
248 	struct kfd_process_device *pdd;
249 	dma_addr_t *dma_addr;
250 	struct device *dev;
251 	struct kfd_process *p;
252 	uint32_t gpuidx;
253 
254 	p = container_of(prange->svms, struct kfd_process, svms);
255 
256 	for (gpuidx = 0; gpuidx < MAX_GPU_INSTANCE; gpuidx++) {
257 		dma_addr = prange->dma_addr[gpuidx];
258 		if (!dma_addr)
259 			continue;
260 
261 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
262 		if (!pdd) {
263 			pr_debug("failed to find device idx %d\n", gpuidx);
264 			continue;
265 		}
266 		dev = &pdd->dev->adev->pdev->dev;
267 		if (unmap_dma)
268 			svm_range_dma_unmap(dev, dma_addr, 0, prange->npages);
269 		kvfree(dma_addr);
270 		prange->dma_addr[gpuidx] = NULL;
271 	}
272 }
273 
274 static void svm_range_free(struct svm_range *prange, bool do_unmap)
275 {
276 	uint64_t size = (prange->last - prange->start + 1) << PAGE_SHIFT;
277 	struct kfd_process *p = container_of(prange->svms, struct kfd_process, svms);
278 
279 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms, prange,
280 		 prange->start, prange->last);
281 
282 	svm_range_vram_node_free(prange);
283 	svm_range_free_dma_mappings(prange, do_unmap);
284 
285 	if (do_unmap && !p->xnack_enabled) {
286 		pr_debug("unreserve prange 0x%p size: 0x%llx\n", prange, size);
287 		amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
288 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
289 	}
290 	mutex_destroy(&prange->lock);
291 	mutex_destroy(&prange->migrate_mutex);
292 	kfree(prange);
293 }
294 
295 static void
296 svm_range_set_default_attributes(int32_t *location, int32_t *prefetch_loc,
297 				 uint8_t *granularity, uint32_t *flags)
298 {
299 	*location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
300 	*prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
301 	*granularity = 9;
302 	*flags =
303 		KFD_IOCTL_SVM_FLAG_HOST_ACCESS | KFD_IOCTL_SVM_FLAG_COHERENT;
304 }
305 
306 static struct
307 svm_range *svm_range_new(struct svm_range_list *svms, uint64_t start,
308 			 uint64_t last, bool update_mem_usage)
309 {
310 	uint64_t size = last - start + 1;
311 	struct svm_range *prange;
312 	struct kfd_process *p;
313 
314 	prange = kzalloc(sizeof(*prange), GFP_KERNEL);
315 	if (!prange)
316 		return NULL;
317 
318 	p = container_of(svms, struct kfd_process, svms);
319 	if (!p->xnack_enabled && update_mem_usage &&
320 	    amdgpu_amdkfd_reserve_mem_limit(NULL, size << PAGE_SHIFT,
321 				    KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0)) {
322 		pr_info("SVM mapping failed, exceeds resident system memory limit\n");
323 		kfree(prange);
324 		return NULL;
325 	}
326 	prange->npages = size;
327 	prange->svms = svms;
328 	prange->start = start;
329 	prange->last = last;
330 	INIT_LIST_HEAD(&prange->list);
331 	INIT_LIST_HEAD(&prange->update_list);
332 	INIT_LIST_HEAD(&prange->svm_bo_list);
333 	INIT_LIST_HEAD(&prange->deferred_list);
334 	INIT_LIST_HEAD(&prange->child_list);
335 	atomic_set(&prange->invalid, 0);
336 	prange->validate_timestamp = 0;
337 	mutex_init(&prange->migrate_mutex);
338 	mutex_init(&prange->lock);
339 
340 	if (p->xnack_enabled)
341 		bitmap_copy(prange->bitmap_access, svms->bitmap_supported,
342 			    MAX_GPU_INSTANCE);
343 
344 	svm_range_set_default_attributes(&prange->preferred_loc,
345 					 &prange->prefetch_loc,
346 					 &prange->granularity, &prange->flags);
347 
348 	pr_debug("svms 0x%p [0x%llx 0x%llx]\n", svms, start, last);
349 
350 	return prange;
351 }
352 
353 static bool svm_bo_ref_unless_zero(struct svm_range_bo *svm_bo)
354 {
355 	if (!svm_bo || !kref_get_unless_zero(&svm_bo->kref))
356 		return false;
357 
358 	return true;
359 }
360 
361 static void svm_range_bo_release(struct kref *kref)
362 {
363 	struct svm_range_bo *svm_bo;
364 
365 	svm_bo = container_of(kref, struct svm_range_bo, kref);
366 	pr_debug("svm_bo 0x%p\n", svm_bo);
367 
368 	spin_lock(&svm_bo->list_lock);
369 	while (!list_empty(&svm_bo->range_list)) {
370 		struct svm_range *prange =
371 				list_first_entry(&svm_bo->range_list,
372 						struct svm_range, svm_bo_list);
373 		/* list_del_init tells a concurrent svm_range_vram_node_new when
374 		 * it's safe to reuse the svm_bo pointer and svm_bo_list head.
375 		 */
376 		list_del_init(&prange->svm_bo_list);
377 		spin_unlock(&svm_bo->list_lock);
378 
379 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
380 			 prange->start, prange->last);
381 		mutex_lock(&prange->lock);
382 		prange->svm_bo = NULL;
383 		mutex_unlock(&prange->lock);
384 
385 		spin_lock(&svm_bo->list_lock);
386 	}
387 	spin_unlock(&svm_bo->list_lock);
388 	if (!dma_fence_is_signaled(&svm_bo->eviction_fence->base)) {
389 		/* We're not in the eviction worker.
390 		 * Signal the fence and synchronize with any
391 		 * pending eviction work.
392 		 */
393 		dma_fence_signal(&svm_bo->eviction_fence->base);
394 		cancel_work_sync(&svm_bo->eviction_work);
395 	}
396 	dma_fence_put(&svm_bo->eviction_fence->base);
397 	amdgpu_bo_unref(&svm_bo->bo);
398 	kfree(svm_bo);
399 }
400 
401 static void svm_range_bo_wq_release(struct work_struct *work)
402 {
403 	struct svm_range_bo *svm_bo;
404 
405 	svm_bo = container_of(work, struct svm_range_bo, release_work);
406 	svm_range_bo_release(&svm_bo->kref);
407 }
408 
409 static void svm_range_bo_release_async(struct kref *kref)
410 {
411 	struct svm_range_bo *svm_bo;
412 
413 	svm_bo = container_of(kref, struct svm_range_bo, kref);
414 	pr_debug("svm_bo 0x%p\n", svm_bo);
415 	INIT_WORK(&svm_bo->release_work, svm_range_bo_wq_release);
416 	schedule_work(&svm_bo->release_work);
417 }
418 
419 void svm_range_bo_unref_async(struct svm_range_bo *svm_bo)
420 {
421 	kref_put(&svm_bo->kref, svm_range_bo_release_async);
422 }
423 
424 static void svm_range_bo_unref(struct svm_range_bo *svm_bo)
425 {
426 	if (svm_bo)
427 		kref_put(&svm_bo->kref, svm_range_bo_release);
428 }
429 
430 static bool
431 svm_range_validate_svm_bo(struct kfd_node *node, struct svm_range *prange)
432 {
433 	mutex_lock(&prange->lock);
434 	if (!prange->svm_bo) {
435 		mutex_unlock(&prange->lock);
436 		return false;
437 	}
438 	if (prange->ttm_res) {
439 		/* We still have a reference, all is well */
440 		mutex_unlock(&prange->lock);
441 		return true;
442 	}
443 	if (svm_bo_ref_unless_zero(prange->svm_bo)) {
444 		/*
445 		 * Migrate from GPU to GPU, remove range from source svm_bo->node
446 		 * range list, and return false to allocate svm_bo from destination
447 		 * node.
448 		 */
449 		if (prange->svm_bo->node != node) {
450 			mutex_unlock(&prange->lock);
451 
452 			spin_lock(&prange->svm_bo->list_lock);
453 			list_del_init(&prange->svm_bo_list);
454 			spin_unlock(&prange->svm_bo->list_lock);
455 
456 			svm_range_bo_unref(prange->svm_bo);
457 			return false;
458 		}
459 		if (READ_ONCE(prange->svm_bo->evicting)) {
460 			struct dma_fence *f;
461 			struct svm_range_bo *svm_bo;
462 			/* The BO is getting evicted,
463 			 * we need to get a new one
464 			 */
465 			mutex_unlock(&prange->lock);
466 			svm_bo = prange->svm_bo;
467 			f = dma_fence_get(&svm_bo->eviction_fence->base);
468 			svm_range_bo_unref(prange->svm_bo);
469 			/* wait for the fence to avoid long spin-loop
470 			 * at list_empty_careful
471 			 */
472 			dma_fence_wait(f, false);
473 			dma_fence_put(f);
474 		} else {
475 			/* The BO was still around and we got
476 			 * a new reference to it
477 			 */
478 			mutex_unlock(&prange->lock);
479 			pr_debug("reuse old bo svms 0x%p [0x%lx 0x%lx]\n",
480 				 prange->svms, prange->start, prange->last);
481 
482 			prange->ttm_res = prange->svm_bo->bo->tbo.resource;
483 			return true;
484 		}
485 
486 	} else {
487 		mutex_unlock(&prange->lock);
488 	}
489 
490 	/* We need a new svm_bo. Spin-loop to wait for concurrent
491 	 * svm_range_bo_release to finish removing this range from
492 	 * its range list. After this, it is safe to reuse the
493 	 * svm_bo pointer and svm_bo_list head.
494 	 */
495 	while (!list_empty_careful(&prange->svm_bo_list))
496 		;
497 
498 	return false;
499 }
500 
501 static struct svm_range_bo *svm_range_bo_new(void)
502 {
503 	struct svm_range_bo *svm_bo;
504 
505 	svm_bo = kzalloc(sizeof(*svm_bo), GFP_KERNEL);
506 	if (!svm_bo)
507 		return NULL;
508 
509 	kref_init(&svm_bo->kref);
510 	INIT_LIST_HEAD(&svm_bo->range_list);
511 	spin_lock_init(&svm_bo->list_lock);
512 
513 	return svm_bo;
514 }
515 
516 int
517 svm_range_vram_node_new(struct kfd_node *node, struct svm_range *prange,
518 			bool clear)
519 {
520 	struct amdgpu_bo_param bp;
521 	struct svm_range_bo *svm_bo;
522 	struct amdgpu_bo_user *ubo;
523 	struct amdgpu_bo *bo;
524 	struct kfd_process *p;
525 	struct mm_struct *mm;
526 	int r;
527 
528 	p = container_of(prange->svms, struct kfd_process, svms);
529 	pr_debug("pasid: %x svms 0x%p [0x%lx 0x%lx]\n", p->pasid, prange->svms,
530 		 prange->start, prange->last);
531 
532 	if (svm_range_validate_svm_bo(node, prange))
533 		return 0;
534 
535 	svm_bo = svm_range_bo_new();
536 	if (!svm_bo) {
537 		pr_debug("failed to alloc svm bo\n");
538 		return -ENOMEM;
539 	}
540 	mm = get_task_mm(p->lead_thread);
541 	if (!mm) {
542 		pr_debug("failed to get mm\n");
543 		kfree(svm_bo);
544 		return -ESRCH;
545 	}
546 	svm_bo->node = node;
547 	svm_bo->eviction_fence =
548 		amdgpu_amdkfd_fence_create(dma_fence_context_alloc(1),
549 					   mm,
550 					   svm_bo);
551 	mmput(mm);
552 	INIT_WORK(&svm_bo->eviction_work, svm_range_evict_svm_bo_worker);
553 	svm_bo->evicting = 0;
554 	memset(&bp, 0, sizeof(bp));
555 	bp.size = prange->npages * PAGE_SIZE;
556 	bp.byte_align = PAGE_SIZE;
557 	bp.domain = AMDGPU_GEM_DOMAIN_VRAM;
558 	bp.flags = AMDGPU_GEM_CREATE_NO_CPU_ACCESS;
559 	bp.flags |= clear ? AMDGPU_GEM_CREATE_VRAM_CLEARED : 0;
560 	bp.flags |= AMDGPU_GEM_CREATE_DISCARDABLE;
561 	bp.type = ttm_bo_type_device;
562 	bp.resv = NULL;
563 	if (node->xcp)
564 		bp.xcp_id_plus1 = node->xcp->id + 1;
565 
566 	r = amdgpu_bo_create_user(node->adev, &bp, &ubo);
567 	if (r) {
568 		pr_debug("failed %d to create bo\n", r);
569 		goto create_bo_failed;
570 	}
571 	bo = &ubo->bo;
572 
573 	pr_debug("alloc bo at offset 0x%lx size 0x%lx on partition %d\n",
574 		 bo->tbo.resource->start << PAGE_SHIFT, bp.size,
575 		 bp.xcp_id_plus1 - 1);
576 
577 	r = amdgpu_bo_reserve(bo, true);
578 	if (r) {
579 		pr_debug("failed %d to reserve bo\n", r);
580 		goto reserve_bo_failed;
581 	}
582 
583 	if (clear) {
584 		r = amdgpu_bo_sync_wait(bo, AMDGPU_FENCE_OWNER_KFD, false);
585 		if (r) {
586 			pr_debug("failed %d to sync bo\n", r);
587 			amdgpu_bo_unreserve(bo);
588 			goto reserve_bo_failed;
589 		}
590 	}
591 
592 	r = dma_resv_reserve_fences(bo->tbo.base.resv, 1);
593 	if (r) {
594 		pr_debug("failed %d to reserve bo\n", r);
595 		amdgpu_bo_unreserve(bo);
596 		goto reserve_bo_failed;
597 	}
598 	amdgpu_bo_fence(bo, &svm_bo->eviction_fence->base, true);
599 
600 	amdgpu_bo_unreserve(bo);
601 
602 	svm_bo->bo = bo;
603 	prange->svm_bo = svm_bo;
604 	prange->ttm_res = bo->tbo.resource;
605 	prange->offset = 0;
606 
607 	spin_lock(&svm_bo->list_lock);
608 	list_add(&prange->svm_bo_list, &svm_bo->range_list);
609 	spin_unlock(&svm_bo->list_lock);
610 
611 	return 0;
612 
613 reserve_bo_failed:
614 	amdgpu_bo_unref(&bo);
615 create_bo_failed:
616 	dma_fence_put(&svm_bo->eviction_fence->base);
617 	kfree(svm_bo);
618 	prange->ttm_res = NULL;
619 
620 	return r;
621 }
622 
623 void svm_range_vram_node_free(struct svm_range *prange)
624 {
625 	svm_range_bo_unref(prange->svm_bo);
626 	prange->ttm_res = NULL;
627 }
628 
629 struct kfd_node *
630 svm_range_get_node_by_id(struct svm_range *prange, uint32_t gpu_id)
631 {
632 	struct kfd_process *p;
633 	struct kfd_process_device *pdd;
634 
635 	p = container_of(prange->svms, struct kfd_process, svms);
636 	pdd = kfd_process_device_data_by_id(p, gpu_id);
637 	if (!pdd) {
638 		pr_debug("failed to get kfd process device by id 0x%x\n", gpu_id);
639 		return NULL;
640 	}
641 
642 	return pdd->dev;
643 }
644 
645 struct kfd_process_device *
646 svm_range_get_pdd_by_node(struct svm_range *prange, struct kfd_node *node)
647 {
648 	struct kfd_process *p;
649 
650 	p = container_of(prange->svms, struct kfd_process, svms);
651 
652 	return kfd_get_process_device_data(node, p);
653 }
654 
655 static int svm_range_bo_validate(void *param, struct amdgpu_bo *bo)
656 {
657 	struct ttm_operation_ctx ctx = { false, false };
658 
659 	amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_VRAM);
660 
661 	return ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
662 }
663 
664 static int
665 svm_range_check_attr(struct kfd_process *p,
666 		     uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
667 {
668 	uint32_t i;
669 
670 	for (i = 0; i < nattr; i++) {
671 		uint32_t val = attrs[i].value;
672 		int gpuidx = MAX_GPU_INSTANCE;
673 
674 		switch (attrs[i].type) {
675 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
676 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM &&
677 			    val != KFD_IOCTL_SVM_LOCATION_UNDEFINED)
678 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
679 			break;
680 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
681 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM)
682 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
683 			break;
684 		case KFD_IOCTL_SVM_ATTR_ACCESS:
685 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
686 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
687 			gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
688 			break;
689 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
690 			break;
691 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
692 			break;
693 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
694 			break;
695 		default:
696 			pr_debug("unknown attr type 0x%x\n", attrs[i].type);
697 			return -EINVAL;
698 		}
699 
700 		if (gpuidx < 0) {
701 			pr_debug("no GPU 0x%x found\n", val);
702 			return -EINVAL;
703 		} else if (gpuidx < MAX_GPU_INSTANCE &&
704 			   !test_bit(gpuidx, p->svms.bitmap_supported)) {
705 			pr_debug("GPU 0x%x not supported\n", val);
706 			return -EINVAL;
707 		}
708 	}
709 
710 	return 0;
711 }
712 
713 static void
714 svm_range_apply_attrs(struct kfd_process *p, struct svm_range *prange,
715 		      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
716 		      bool *update_mapping)
717 {
718 	uint32_t i;
719 	int gpuidx;
720 
721 	for (i = 0; i < nattr; i++) {
722 		switch (attrs[i].type) {
723 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
724 			prange->preferred_loc = attrs[i].value;
725 			break;
726 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
727 			prange->prefetch_loc = attrs[i].value;
728 			break;
729 		case KFD_IOCTL_SVM_ATTR_ACCESS:
730 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
731 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
732 			if (!p->xnack_enabled)
733 				*update_mapping = true;
734 
735 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
736 							       attrs[i].value);
737 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
738 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
739 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
740 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
741 				bitmap_set(prange->bitmap_access, gpuidx, 1);
742 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
743 			} else {
744 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
745 				bitmap_set(prange->bitmap_aip, gpuidx, 1);
746 			}
747 			break;
748 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
749 			*update_mapping = true;
750 			prange->flags |= attrs[i].value;
751 			break;
752 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
753 			*update_mapping = true;
754 			prange->flags &= ~attrs[i].value;
755 			break;
756 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
757 			prange->granularity = attrs[i].value;
758 			break;
759 		default:
760 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
761 		}
762 	}
763 }
764 
765 static bool
766 svm_range_is_same_attrs(struct kfd_process *p, struct svm_range *prange,
767 			uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
768 {
769 	uint32_t i;
770 	int gpuidx;
771 
772 	for (i = 0; i < nattr; i++) {
773 		switch (attrs[i].type) {
774 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
775 			if (prange->preferred_loc != attrs[i].value)
776 				return false;
777 			break;
778 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
779 			/* Prefetch should always trigger a migration even
780 			 * if the value of the attribute didn't change.
781 			 */
782 			return false;
783 		case KFD_IOCTL_SVM_ATTR_ACCESS:
784 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
785 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
786 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
787 							       attrs[i].value);
788 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
789 				if (test_bit(gpuidx, prange->bitmap_access) ||
790 				    test_bit(gpuidx, prange->bitmap_aip))
791 					return false;
792 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
793 				if (!test_bit(gpuidx, prange->bitmap_access))
794 					return false;
795 			} else {
796 				if (!test_bit(gpuidx, prange->bitmap_aip))
797 					return false;
798 			}
799 			break;
800 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
801 			if ((prange->flags & attrs[i].value) != attrs[i].value)
802 				return false;
803 			break;
804 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
805 			if ((prange->flags & attrs[i].value) != 0)
806 				return false;
807 			break;
808 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
809 			if (prange->granularity != attrs[i].value)
810 				return false;
811 			break;
812 		default:
813 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
814 		}
815 	}
816 
817 	return !prange->is_error_flag;
818 }
819 
820 /**
821  * svm_range_debug_dump - print all range information from svms
822  * @svms: svm range list header
823  *
824  * debug output svm range start, end, prefetch location from svms
825  * interval tree and link list
826  *
827  * Context: The caller must hold svms->lock
828  */
829 static void svm_range_debug_dump(struct svm_range_list *svms)
830 {
831 	struct interval_tree_node *node;
832 	struct svm_range *prange;
833 
834 	pr_debug("dump svms 0x%p list\n", svms);
835 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
836 
837 	list_for_each_entry(prange, &svms->list, list) {
838 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
839 			 prange, prange->start, prange->npages,
840 			 prange->start + prange->npages - 1,
841 			 prange->actual_loc);
842 	}
843 
844 	pr_debug("dump svms 0x%p interval tree\n", svms);
845 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
846 	node = interval_tree_iter_first(&svms->objects, 0, ~0ULL);
847 	while (node) {
848 		prange = container_of(node, struct svm_range, it_node);
849 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
850 			 prange, prange->start, prange->npages,
851 			 prange->start + prange->npages - 1,
852 			 prange->actual_loc);
853 		node = interval_tree_iter_next(node, 0, ~0ULL);
854 	}
855 }
856 
857 static void *
858 svm_range_copy_array(void *psrc, size_t size, uint64_t num_elements,
859 		     uint64_t offset)
860 {
861 	unsigned char *dst;
862 
863 	dst = kvmalloc_array(num_elements, size, GFP_KERNEL);
864 	if (!dst)
865 		return NULL;
866 	memcpy(dst, (unsigned char *)psrc + offset, num_elements * size);
867 
868 	return (void *)dst;
869 }
870 
871 static int
872 svm_range_copy_dma_addrs(struct svm_range *dst, struct svm_range *src)
873 {
874 	int i;
875 
876 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
877 		if (!src->dma_addr[i])
878 			continue;
879 		dst->dma_addr[i] = svm_range_copy_array(src->dma_addr[i],
880 					sizeof(*src->dma_addr[i]), src->npages, 0);
881 		if (!dst->dma_addr[i])
882 			return -ENOMEM;
883 	}
884 
885 	return 0;
886 }
887 
888 static int
889 svm_range_split_array(void *ppnew, void *ppold, size_t size,
890 		      uint64_t old_start, uint64_t old_n,
891 		      uint64_t new_start, uint64_t new_n)
892 {
893 	unsigned char *new, *old, *pold;
894 	uint64_t d;
895 
896 	if (!ppold)
897 		return 0;
898 	pold = *(unsigned char **)ppold;
899 	if (!pold)
900 		return 0;
901 
902 	d = (new_start - old_start) * size;
903 	new = svm_range_copy_array(pold, size, new_n, d);
904 	if (!new)
905 		return -ENOMEM;
906 	d = (new_start == old_start) ? new_n * size : 0;
907 	old = svm_range_copy_array(pold, size, old_n, d);
908 	if (!old) {
909 		kvfree(new);
910 		return -ENOMEM;
911 	}
912 	kvfree(pold);
913 	*(void **)ppold = old;
914 	*(void **)ppnew = new;
915 
916 	return 0;
917 }
918 
919 static int
920 svm_range_split_pages(struct svm_range *new, struct svm_range *old,
921 		      uint64_t start, uint64_t last)
922 {
923 	uint64_t npages = last - start + 1;
924 	int i, r;
925 
926 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
927 		r = svm_range_split_array(&new->dma_addr[i], &old->dma_addr[i],
928 					  sizeof(*old->dma_addr[i]), old->start,
929 					  npages, new->start, new->npages);
930 		if (r)
931 			return r;
932 	}
933 
934 	return 0;
935 }
936 
937 static int
938 svm_range_split_nodes(struct svm_range *new, struct svm_range *old,
939 		      uint64_t start, uint64_t last)
940 {
941 	uint64_t npages = last - start + 1;
942 
943 	pr_debug("svms 0x%p new prange 0x%p start 0x%lx [0x%llx 0x%llx]\n",
944 		 new->svms, new, new->start, start, last);
945 
946 	if (new->start == old->start) {
947 		new->offset = old->offset;
948 		old->offset += new->npages;
949 	} else {
950 		new->offset = old->offset + npages;
951 	}
952 
953 	new->svm_bo = svm_range_bo_ref(old->svm_bo);
954 	new->ttm_res = old->ttm_res;
955 
956 	spin_lock(&new->svm_bo->list_lock);
957 	list_add(&new->svm_bo_list, &new->svm_bo->range_list);
958 	spin_unlock(&new->svm_bo->list_lock);
959 
960 	return 0;
961 }
962 
963 /**
964  * svm_range_split_adjust - split range and adjust
965  *
966  * @new: new range
967  * @old: the old range
968  * @start: the old range adjust to start address in pages
969  * @last: the old range adjust to last address in pages
970  *
971  * Copy system memory dma_addr or vram ttm_res in old range to new
972  * range from new_start up to size new->npages, the remaining old range is from
973  * start to last
974  *
975  * Return:
976  * 0 - OK, -ENOMEM - out of memory
977  */
978 static int
979 svm_range_split_adjust(struct svm_range *new, struct svm_range *old,
980 		      uint64_t start, uint64_t last)
981 {
982 	int r;
983 
984 	pr_debug("svms 0x%p new 0x%lx old [0x%lx 0x%lx] => [0x%llx 0x%llx]\n",
985 		 new->svms, new->start, old->start, old->last, start, last);
986 
987 	if (new->start < old->start ||
988 	    new->last > old->last) {
989 		WARN_ONCE(1, "invalid new range start or last\n");
990 		return -EINVAL;
991 	}
992 
993 	r = svm_range_split_pages(new, old, start, last);
994 	if (r)
995 		return r;
996 
997 	if (old->actual_loc && old->ttm_res) {
998 		r = svm_range_split_nodes(new, old, start, last);
999 		if (r)
1000 			return r;
1001 	}
1002 
1003 	old->npages = last - start + 1;
1004 	old->start = start;
1005 	old->last = last;
1006 	new->flags = old->flags;
1007 	new->preferred_loc = old->preferred_loc;
1008 	new->prefetch_loc = old->prefetch_loc;
1009 	new->actual_loc = old->actual_loc;
1010 	new->granularity = old->granularity;
1011 	new->mapped_to_gpu = old->mapped_to_gpu;
1012 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
1013 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
1014 
1015 	return 0;
1016 }
1017 
1018 /**
1019  * svm_range_split - split a range in 2 ranges
1020  *
1021  * @prange: the svm range to split
1022  * @start: the remaining range start address in pages
1023  * @last: the remaining range last address in pages
1024  * @new: the result new range generated
1025  *
1026  * Two cases only:
1027  * case 1: if start == prange->start
1028  *         prange ==> prange[start, last]
1029  *         new range [last + 1, prange->last]
1030  *
1031  * case 2: if last == prange->last
1032  *         prange ==> prange[start, last]
1033  *         new range [prange->start, start - 1]
1034  *
1035  * Return:
1036  * 0 - OK, -ENOMEM - out of memory, -EINVAL - invalid start, last
1037  */
1038 static int
1039 svm_range_split(struct svm_range *prange, uint64_t start, uint64_t last,
1040 		struct svm_range **new)
1041 {
1042 	uint64_t old_start = prange->start;
1043 	uint64_t old_last = prange->last;
1044 	struct svm_range_list *svms;
1045 	int r = 0;
1046 
1047 	pr_debug("svms 0x%p [0x%llx 0x%llx] to [0x%llx 0x%llx]\n", prange->svms,
1048 		 old_start, old_last, start, last);
1049 
1050 	if (old_start != start && old_last != last)
1051 		return -EINVAL;
1052 	if (start < old_start || last > old_last)
1053 		return -EINVAL;
1054 
1055 	svms = prange->svms;
1056 	if (old_start == start)
1057 		*new = svm_range_new(svms, last + 1, old_last, false);
1058 	else
1059 		*new = svm_range_new(svms, old_start, start - 1, false);
1060 	if (!*new)
1061 		return -ENOMEM;
1062 
1063 	r = svm_range_split_adjust(*new, prange, start, last);
1064 	if (r) {
1065 		pr_debug("failed %d split [0x%llx 0x%llx] to [0x%llx 0x%llx]\n",
1066 			 r, old_start, old_last, start, last);
1067 		svm_range_free(*new, false);
1068 		*new = NULL;
1069 	}
1070 
1071 	return r;
1072 }
1073 
1074 static int
1075 svm_range_split_tail(struct svm_range *prange,
1076 		     uint64_t new_last, struct list_head *insert_list)
1077 {
1078 	struct svm_range *tail;
1079 	int r = svm_range_split(prange, prange->start, new_last, &tail);
1080 
1081 	if (!r)
1082 		list_add(&tail->list, insert_list);
1083 	return r;
1084 }
1085 
1086 static int
1087 svm_range_split_head(struct svm_range *prange,
1088 		     uint64_t new_start, struct list_head *insert_list)
1089 {
1090 	struct svm_range *head;
1091 	int r = svm_range_split(prange, new_start, prange->last, &head);
1092 
1093 	if (!r)
1094 		list_add(&head->list, insert_list);
1095 	return r;
1096 }
1097 
1098 static void
1099 svm_range_add_child(struct svm_range *prange, struct mm_struct *mm,
1100 		    struct svm_range *pchild, enum svm_work_list_ops op)
1101 {
1102 	pr_debug("add child 0x%p [0x%lx 0x%lx] to prange 0x%p child list %d\n",
1103 		 pchild, pchild->start, pchild->last, prange, op);
1104 
1105 	pchild->work_item.mm = mm;
1106 	pchild->work_item.op = op;
1107 	list_add_tail(&pchild->child_list, &prange->child_list);
1108 }
1109 
1110 /**
1111  * svm_range_split_by_granularity - collect ranges within granularity boundary
1112  *
1113  * @p: the process with svms list
1114  * @mm: mm structure
1115  * @addr: the vm fault address in pages, to split the prange
1116  * @parent: parent range if prange is from child list
1117  * @prange: prange to split
1118  *
1119  * Trims @prange to be a single aligned block of prange->granularity if
1120  * possible. The head and tail are added to the child_list in @parent.
1121  *
1122  * Context: caller must hold mmap_read_lock and prange->lock
1123  *
1124  * Return:
1125  * 0 - OK, otherwise error code
1126  */
1127 int
1128 svm_range_split_by_granularity(struct kfd_process *p, struct mm_struct *mm,
1129 			       unsigned long addr, struct svm_range *parent,
1130 			       struct svm_range *prange)
1131 {
1132 	struct svm_range *head, *tail;
1133 	unsigned long start, last, size;
1134 	int r;
1135 
1136 	/* Align splited range start and size to granularity size, then a single
1137 	 * PTE will be used for whole range, this reduces the number of PTE
1138 	 * updated and the L1 TLB space used for translation.
1139 	 */
1140 	size = 1UL << prange->granularity;
1141 	start = ALIGN_DOWN(addr, size);
1142 	last = ALIGN(addr + 1, size) - 1;
1143 
1144 	pr_debug("svms 0x%p split [0x%lx 0x%lx] to [0x%lx 0x%lx] size 0x%lx\n",
1145 		 prange->svms, prange->start, prange->last, start, last, size);
1146 
1147 	if (start > prange->start) {
1148 		r = svm_range_split(prange, start, prange->last, &head);
1149 		if (r)
1150 			return r;
1151 		svm_range_add_child(parent, mm, head, SVM_OP_ADD_RANGE);
1152 	}
1153 
1154 	if (last < prange->last) {
1155 		r = svm_range_split(prange, prange->start, last, &tail);
1156 		if (r)
1157 			return r;
1158 		svm_range_add_child(parent, mm, tail, SVM_OP_ADD_RANGE);
1159 	}
1160 
1161 	/* xnack on, update mapping on GPUs with ACCESS_IN_PLACE */
1162 	if (p->xnack_enabled && prange->work_item.op == SVM_OP_ADD_RANGE) {
1163 		prange->work_item.op = SVM_OP_ADD_RANGE_AND_MAP;
1164 		pr_debug("change prange 0x%p [0x%lx 0x%lx] op %d\n",
1165 			 prange, prange->start, prange->last,
1166 			 SVM_OP_ADD_RANGE_AND_MAP);
1167 	}
1168 	return 0;
1169 }
1170 static bool
1171 svm_nodes_in_same_hive(struct kfd_node *node_a, struct kfd_node *node_b)
1172 {
1173 	return (node_a->adev == node_b->adev ||
1174 		amdgpu_xgmi_same_hive(node_a->adev, node_b->adev));
1175 }
1176 
1177 static uint64_t
1178 svm_range_get_pte_flags(struct kfd_node *node,
1179 			struct svm_range *prange, int domain)
1180 {
1181 	struct kfd_node *bo_node;
1182 	uint32_t flags = prange->flags;
1183 	uint32_t mapping_flags = 0;
1184 	uint64_t pte_flags;
1185 	bool snoop = (domain != SVM_RANGE_VRAM_DOMAIN);
1186 	bool coherent = flags & KFD_IOCTL_SVM_FLAG_COHERENT;
1187 	bool uncached = false; /*flags & KFD_IOCTL_SVM_FLAG_UNCACHED;*/
1188 	unsigned int mtype_local;
1189 
1190 	if (domain == SVM_RANGE_VRAM_DOMAIN)
1191 		bo_node = prange->svm_bo->node;
1192 
1193 	switch (node->adev->ip_versions[GC_HWIP][0]) {
1194 	case IP_VERSION(9, 4, 1):
1195 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1196 			if (bo_node == node) {
1197 				mapping_flags |= coherent ?
1198 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1199 			} else {
1200 				mapping_flags |= coherent ?
1201 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1202 				if (svm_nodes_in_same_hive(node, bo_node))
1203 					snoop = true;
1204 			}
1205 		} else {
1206 			mapping_flags |= coherent ?
1207 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1208 		}
1209 		break;
1210 	case IP_VERSION(9, 4, 2):
1211 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1212 			if (bo_node == node) {
1213 				mapping_flags |= coherent ?
1214 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1215 				if (node->adev->gmc.xgmi.connected_to_cpu)
1216 					snoop = true;
1217 			} else {
1218 				mapping_flags |= coherent ?
1219 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1220 				if (svm_nodes_in_same_hive(node, bo_node))
1221 					snoop = true;
1222 			}
1223 		} else {
1224 			mapping_flags |= coherent ?
1225 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1226 		}
1227 		break;
1228 	case IP_VERSION(9, 4, 3):
1229 		mtype_local = amdgpu_mtype_local == 1 ? AMDGPU_VM_MTYPE_NC :
1230 			     (amdgpu_mtype_local == 2 ? AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW);
1231 		snoop = true;
1232 		if (uncached) {
1233 			mapping_flags |= AMDGPU_VM_MTYPE_UC;
1234 		} else if (domain == SVM_RANGE_VRAM_DOMAIN) {
1235 			/* local HBM region close to partition */
1236 			if (bo_node->adev == node->adev &&
1237 			    (!bo_node->xcp || !node->xcp || bo_node->xcp->mem_id == node->xcp->mem_id))
1238 				mapping_flags |= mtype_local;
1239 			/* local HBM region far from partition or remote XGMI GPU */
1240 			else if (svm_nodes_in_same_hive(bo_node, node))
1241 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1242 			/* PCIe P2P */
1243 			else
1244 				mapping_flags |= AMDGPU_VM_MTYPE_UC;
1245 		/* system memory accessed by the APU */
1246 		} else if (node->adev->flags & AMD_IS_APU) {
1247 			/* On NUMA systems, locality is determined per-page
1248 			 * in amdgpu_gmc_override_vm_pte_flags
1249 			 */
1250 			if (num_possible_nodes() <= 1)
1251 				mapping_flags |= mtype_local;
1252 			else
1253 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1254 		/* system memory accessed by the dGPU */
1255 		} else {
1256 			mapping_flags |= AMDGPU_VM_MTYPE_UC;
1257 		}
1258 		break;
1259 	default:
1260 		mapping_flags |= coherent ?
1261 			AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1262 	}
1263 
1264 	mapping_flags |= AMDGPU_VM_PAGE_READABLE | AMDGPU_VM_PAGE_WRITEABLE;
1265 
1266 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_RO)
1267 		mapping_flags &= ~AMDGPU_VM_PAGE_WRITEABLE;
1268 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_EXEC)
1269 		mapping_flags |= AMDGPU_VM_PAGE_EXECUTABLE;
1270 
1271 	pte_flags = AMDGPU_PTE_VALID;
1272 	pte_flags |= (domain == SVM_RANGE_VRAM_DOMAIN) ? 0 : AMDGPU_PTE_SYSTEM;
1273 	pte_flags |= snoop ? AMDGPU_PTE_SNOOPED : 0;
1274 
1275 	pte_flags |= amdgpu_gem_va_map_flags(node->adev, mapping_flags);
1276 	return pte_flags;
1277 }
1278 
1279 static int
1280 svm_range_unmap_from_gpu(struct amdgpu_device *adev, struct amdgpu_vm *vm,
1281 			 uint64_t start, uint64_t last,
1282 			 struct dma_fence **fence)
1283 {
1284 	uint64_t init_pte_value = 0;
1285 
1286 	pr_debug("[0x%llx 0x%llx]\n", start, last);
1287 
1288 	return amdgpu_vm_update_range(adev, vm, false, true, true, NULL, start,
1289 				      last, init_pte_value, 0, 0, NULL, NULL,
1290 				      fence);
1291 }
1292 
1293 static int
1294 svm_range_unmap_from_gpus(struct svm_range *prange, unsigned long start,
1295 			  unsigned long last, uint32_t trigger)
1296 {
1297 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1298 	struct kfd_process_device *pdd;
1299 	struct dma_fence *fence = NULL;
1300 	struct kfd_process *p;
1301 	uint32_t gpuidx;
1302 	int r = 0;
1303 
1304 	if (!prange->mapped_to_gpu) {
1305 		pr_debug("prange 0x%p [0x%lx 0x%lx] not mapped to GPU\n",
1306 			 prange, prange->start, prange->last);
1307 		return 0;
1308 	}
1309 
1310 	if (prange->start == start && prange->last == last) {
1311 		pr_debug("unmap svms 0x%p prange 0x%p\n", prange->svms, prange);
1312 		prange->mapped_to_gpu = false;
1313 	}
1314 
1315 	bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
1316 		  MAX_GPU_INSTANCE);
1317 	p = container_of(prange->svms, struct kfd_process, svms);
1318 
1319 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1320 		pr_debug("unmap from gpu idx 0x%x\n", gpuidx);
1321 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1322 		if (!pdd) {
1323 			pr_debug("failed to find device idx %d\n", gpuidx);
1324 			return -EINVAL;
1325 		}
1326 
1327 		kfd_smi_event_unmap_from_gpu(pdd->dev, p->lead_thread->pid,
1328 					     start, last, trigger);
1329 
1330 		r = svm_range_unmap_from_gpu(pdd->dev->adev,
1331 					     drm_priv_to_vm(pdd->drm_priv),
1332 					     start, last, &fence);
1333 		if (r)
1334 			break;
1335 
1336 		if (fence) {
1337 			r = dma_fence_wait(fence, false);
1338 			dma_fence_put(fence);
1339 			fence = NULL;
1340 			if (r)
1341 				break;
1342 		}
1343 		kfd_flush_tlb(pdd, TLB_FLUSH_HEAVYWEIGHT);
1344 	}
1345 
1346 	return r;
1347 }
1348 
1349 static int
1350 svm_range_map_to_gpu(struct kfd_process_device *pdd, struct svm_range *prange,
1351 		     unsigned long offset, unsigned long npages, bool readonly,
1352 		     dma_addr_t *dma_addr, struct amdgpu_device *bo_adev,
1353 		     struct dma_fence **fence, bool flush_tlb)
1354 {
1355 	struct amdgpu_device *adev = pdd->dev->adev;
1356 	struct amdgpu_vm *vm = drm_priv_to_vm(pdd->drm_priv);
1357 	uint64_t pte_flags;
1358 	unsigned long last_start;
1359 	int last_domain;
1360 	int r = 0;
1361 	int64_t i, j;
1362 
1363 	last_start = prange->start + offset;
1364 
1365 	pr_debug("svms 0x%p [0x%lx 0x%lx] readonly %d\n", prange->svms,
1366 		 last_start, last_start + npages - 1, readonly);
1367 
1368 	for (i = offset; i < offset + npages; i++) {
1369 		last_domain = dma_addr[i] & SVM_RANGE_VRAM_DOMAIN;
1370 		dma_addr[i] &= ~SVM_RANGE_VRAM_DOMAIN;
1371 
1372 		/* Collect all pages in the same address range and memory domain
1373 		 * that can be mapped with a single call to update mapping.
1374 		 */
1375 		if (i < offset + npages - 1 &&
1376 		    last_domain == (dma_addr[i + 1] & SVM_RANGE_VRAM_DOMAIN))
1377 			continue;
1378 
1379 		pr_debug("Mapping range [0x%lx 0x%llx] on domain: %s\n",
1380 			 last_start, prange->start + i, last_domain ? "GPU" : "CPU");
1381 
1382 		pte_flags = svm_range_get_pte_flags(pdd->dev, prange, last_domain);
1383 		if (readonly)
1384 			pte_flags &= ~AMDGPU_PTE_WRITEABLE;
1385 
1386 		pr_debug("svms 0x%p map [0x%lx 0x%llx] vram %d PTE 0x%llx\n",
1387 			 prange->svms, last_start, prange->start + i,
1388 			 (last_domain == SVM_RANGE_VRAM_DOMAIN) ? 1 : 0,
1389 			 pte_flags);
1390 
1391 		/* For dGPU mode, we use same vm_manager to allocate VRAM for
1392 		 * different memory partition based on fpfn/lpfn, we should use
1393 		 * same vm_manager.vram_base_offset regardless memory partition.
1394 		 */
1395 		r = amdgpu_vm_update_range(adev, vm, false, false, flush_tlb, NULL,
1396 					   last_start, prange->start + i,
1397 					   pte_flags,
1398 					   (last_start - prange->start) << PAGE_SHIFT,
1399 					   bo_adev ? bo_adev->vm_manager.vram_base_offset : 0,
1400 					   NULL, dma_addr, &vm->last_update);
1401 
1402 		for (j = last_start - prange->start; j <= i; j++)
1403 			dma_addr[j] |= last_domain;
1404 
1405 		if (r) {
1406 			pr_debug("failed %d to map to gpu 0x%lx\n", r, prange->start);
1407 			goto out;
1408 		}
1409 		last_start = prange->start + i + 1;
1410 	}
1411 
1412 	r = amdgpu_vm_update_pdes(adev, vm, false);
1413 	if (r) {
1414 		pr_debug("failed %d to update directories 0x%lx\n", r,
1415 			 prange->start);
1416 		goto out;
1417 	}
1418 
1419 	if (fence)
1420 		*fence = dma_fence_get(vm->last_update);
1421 
1422 out:
1423 	return r;
1424 }
1425 
1426 static int
1427 svm_range_map_to_gpus(struct svm_range *prange, unsigned long offset,
1428 		      unsigned long npages, bool readonly,
1429 		      unsigned long *bitmap, bool wait, bool flush_tlb)
1430 {
1431 	struct kfd_process_device *pdd;
1432 	struct amdgpu_device *bo_adev = NULL;
1433 	struct kfd_process *p;
1434 	struct dma_fence *fence = NULL;
1435 	uint32_t gpuidx;
1436 	int r = 0;
1437 
1438 	if (prange->svm_bo && prange->ttm_res)
1439 		bo_adev = prange->svm_bo->node->adev;
1440 
1441 	p = container_of(prange->svms, struct kfd_process, svms);
1442 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1443 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
1444 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1445 		if (!pdd) {
1446 			pr_debug("failed to find device idx %d\n", gpuidx);
1447 			return -EINVAL;
1448 		}
1449 
1450 		pdd = kfd_bind_process_to_device(pdd->dev, p);
1451 		if (IS_ERR(pdd))
1452 			return -EINVAL;
1453 
1454 		if (bo_adev && pdd->dev->adev != bo_adev &&
1455 		    !amdgpu_xgmi_same_hive(pdd->dev->adev, bo_adev)) {
1456 			pr_debug("cannot map to device idx %d\n", gpuidx);
1457 			continue;
1458 		}
1459 
1460 		r = svm_range_map_to_gpu(pdd, prange, offset, npages, readonly,
1461 					 prange->dma_addr[gpuidx],
1462 					 bo_adev, wait ? &fence : NULL,
1463 					 flush_tlb);
1464 		if (r)
1465 			break;
1466 
1467 		if (fence) {
1468 			r = dma_fence_wait(fence, false);
1469 			dma_fence_put(fence);
1470 			fence = NULL;
1471 			if (r) {
1472 				pr_debug("failed %d to dma fence wait\n", r);
1473 				break;
1474 			}
1475 		}
1476 
1477 		kfd_flush_tlb(pdd, TLB_FLUSH_LEGACY);
1478 	}
1479 
1480 	return r;
1481 }
1482 
1483 struct svm_validate_context {
1484 	struct kfd_process *process;
1485 	struct svm_range *prange;
1486 	bool intr;
1487 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1488 	struct drm_exec exec;
1489 };
1490 
1491 static int svm_range_reserve_bos(struct svm_validate_context *ctx, bool intr)
1492 {
1493 	struct kfd_process_device *pdd;
1494 	struct amdgpu_vm *vm;
1495 	uint32_t gpuidx;
1496 	int r;
1497 
1498 	drm_exec_init(&ctx->exec, intr ? DRM_EXEC_INTERRUPTIBLE_WAIT: 0);
1499 	drm_exec_until_all_locked(&ctx->exec) {
1500 		for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1501 			pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1502 			if (!pdd) {
1503 				pr_debug("failed to find device idx %d\n", gpuidx);
1504 				r = -EINVAL;
1505 				goto unreserve_out;
1506 			}
1507 			vm = drm_priv_to_vm(pdd->drm_priv);
1508 
1509 			r = amdgpu_vm_lock_pd(vm, &ctx->exec, 2);
1510 			drm_exec_retry_on_contention(&ctx->exec);
1511 			if (unlikely(r)) {
1512 				pr_debug("failed %d to reserve bo\n", r);
1513 				goto unreserve_out;
1514 			}
1515 		}
1516 	}
1517 
1518 	for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1519 		pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1520 		if (!pdd) {
1521 			pr_debug("failed to find device idx %d\n", gpuidx);
1522 			r = -EINVAL;
1523 			goto unreserve_out;
1524 		}
1525 
1526 		r = amdgpu_vm_validate_pt_bos(pdd->dev->adev,
1527 					      drm_priv_to_vm(pdd->drm_priv),
1528 					      svm_range_bo_validate, NULL);
1529 		if (r) {
1530 			pr_debug("failed %d validate pt bos\n", r);
1531 			goto unreserve_out;
1532 		}
1533 	}
1534 
1535 	return 0;
1536 
1537 unreserve_out:
1538 	drm_exec_fini(&ctx->exec);
1539 	return r;
1540 }
1541 
1542 static void svm_range_unreserve_bos(struct svm_validate_context *ctx)
1543 {
1544 	drm_exec_fini(&ctx->exec);
1545 }
1546 
1547 static void *kfd_svm_page_owner(struct kfd_process *p, int32_t gpuidx)
1548 {
1549 	struct kfd_process_device *pdd;
1550 
1551 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1552 	if (!pdd)
1553 		return NULL;
1554 
1555 	return SVM_ADEV_PGMAP_OWNER(pdd->dev->adev);
1556 }
1557 
1558 /*
1559  * Validation+GPU mapping with concurrent invalidation (MMU notifiers)
1560  *
1561  * To prevent concurrent destruction or change of range attributes, the
1562  * svm_read_lock must be held. The caller must not hold the svm_write_lock
1563  * because that would block concurrent evictions and lead to deadlocks. To
1564  * serialize concurrent migrations or validations of the same range, the
1565  * prange->migrate_mutex must be held.
1566  *
1567  * For VRAM ranges, the SVM BO must be allocated and valid (protected by its
1568  * eviction fence.
1569  *
1570  * The following sequence ensures race-free validation and GPU mapping:
1571  *
1572  * 1. Reserve page table (and SVM BO if range is in VRAM)
1573  * 2. hmm_range_fault to get page addresses (if system memory)
1574  * 3. DMA-map pages (if system memory)
1575  * 4-a. Take notifier lock
1576  * 4-b. Check that pages still valid (mmu_interval_read_retry)
1577  * 4-c. Check that the range was not split or otherwise invalidated
1578  * 4-d. Update GPU page table
1579  * 4.e. Release notifier lock
1580  * 5. Release page table (and SVM BO) reservation
1581  */
1582 static int svm_range_validate_and_map(struct mm_struct *mm,
1583 				      struct svm_range *prange, int32_t gpuidx,
1584 				      bool intr, bool wait, bool flush_tlb)
1585 {
1586 	struct svm_validate_context *ctx;
1587 	unsigned long start, end, addr;
1588 	struct kfd_process *p;
1589 	void *owner;
1590 	int32_t idx;
1591 	int r = 0;
1592 
1593 	ctx = kzalloc(sizeof(struct svm_validate_context), GFP_KERNEL);
1594 	if (!ctx)
1595 		return -ENOMEM;
1596 	ctx->process = container_of(prange->svms, struct kfd_process, svms);
1597 	ctx->prange = prange;
1598 	ctx->intr = intr;
1599 
1600 	if (gpuidx < MAX_GPU_INSTANCE) {
1601 		bitmap_zero(ctx->bitmap, MAX_GPU_INSTANCE);
1602 		bitmap_set(ctx->bitmap, gpuidx, 1);
1603 	} else if (ctx->process->xnack_enabled) {
1604 		bitmap_copy(ctx->bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
1605 
1606 		/* If prefetch range to GPU, or GPU retry fault migrate range to
1607 		 * GPU, which has ACCESS attribute to the range, create mapping
1608 		 * on that GPU.
1609 		 */
1610 		if (prange->actual_loc) {
1611 			gpuidx = kfd_process_gpuidx_from_gpuid(ctx->process,
1612 							prange->actual_loc);
1613 			if (gpuidx < 0) {
1614 				WARN_ONCE(1, "failed get device by id 0x%x\n",
1615 					 prange->actual_loc);
1616 				r = -EINVAL;
1617 				goto free_ctx;
1618 			}
1619 			if (test_bit(gpuidx, prange->bitmap_access))
1620 				bitmap_set(ctx->bitmap, gpuidx, 1);
1621 		}
1622 	} else {
1623 		bitmap_or(ctx->bitmap, prange->bitmap_access,
1624 			  prange->bitmap_aip, MAX_GPU_INSTANCE);
1625 	}
1626 
1627 	if (bitmap_empty(ctx->bitmap, MAX_GPU_INSTANCE)) {
1628 		bitmap_copy(ctx->bitmap, prange->bitmap_access, MAX_GPU_INSTANCE);
1629 		if (!prange->mapped_to_gpu ||
1630 		    bitmap_empty(ctx->bitmap, MAX_GPU_INSTANCE)) {
1631 			r = 0;
1632 			goto free_ctx;
1633 		}
1634 	}
1635 
1636 	if (prange->actual_loc && !prange->ttm_res) {
1637 		/* This should never happen. actual_loc gets set by
1638 		 * svm_migrate_ram_to_vram after allocating a BO.
1639 		 */
1640 		WARN_ONCE(1, "VRAM BO missing during validation\n");
1641 		r = -EINVAL;
1642 		goto free_ctx;
1643 	}
1644 
1645 	svm_range_reserve_bos(ctx, intr);
1646 
1647 	p = container_of(prange->svms, struct kfd_process, svms);
1648 	owner = kfd_svm_page_owner(p, find_first_bit(ctx->bitmap,
1649 						MAX_GPU_INSTANCE));
1650 	for_each_set_bit(idx, ctx->bitmap, MAX_GPU_INSTANCE) {
1651 		if (kfd_svm_page_owner(p, idx) != owner) {
1652 			owner = NULL;
1653 			break;
1654 		}
1655 	}
1656 
1657 	start = prange->start << PAGE_SHIFT;
1658 	end = (prange->last + 1) << PAGE_SHIFT;
1659 	for (addr = start; addr < end && !r; ) {
1660 		struct hmm_range *hmm_range;
1661 		struct vm_area_struct *vma;
1662 		unsigned long next;
1663 		unsigned long offset;
1664 		unsigned long npages;
1665 		bool readonly;
1666 
1667 		vma = vma_lookup(mm, addr);
1668 		if (!vma) {
1669 			r = -EFAULT;
1670 			goto unreserve_out;
1671 		}
1672 		readonly = !(vma->vm_flags & VM_WRITE);
1673 
1674 		next = min(vma->vm_end, end);
1675 		npages = (next - addr) >> PAGE_SHIFT;
1676 		WRITE_ONCE(p->svms.faulting_task, current);
1677 		r = amdgpu_hmm_range_get_pages(&prange->notifier, addr, npages,
1678 					       readonly, owner, NULL,
1679 					       &hmm_range);
1680 		WRITE_ONCE(p->svms.faulting_task, NULL);
1681 		if (r) {
1682 			pr_debug("failed %d to get svm range pages\n", r);
1683 			goto unreserve_out;
1684 		}
1685 
1686 		offset = (addr - start) >> PAGE_SHIFT;
1687 		r = svm_range_dma_map(prange, ctx->bitmap, offset, npages,
1688 				      hmm_range->hmm_pfns);
1689 		if (r) {
1690 			pr_debug("failed %d to dma map range\n", r);
1691 			goto unreserve_out;
1692 		}
1693 
1694 		svm_range_lock(prange);
1695 		if (amdgpu_hmm_range_get_pages_done(hmm_range)) {
1696 			pr_debug("hmm update the range, need validate again\n");
1697 			r = -EAGAIN;
1698 			goto unlock_out;
1699 		}
1700 		if (!list_empty(&prange->child_list)) {
1701 			pr_debug("range split by unmap in parallel, validate again\n");
1702 			r = -EAGAIN;
1703 			goto unlock_out;
1704 		}
1705 
1706 		r = svm_range_map_to_gpus(prange, offset, npages, readonly,
1707 					  ctx->bitmap, wait, flush_tlb);
1708 
1709 unlock_out:
1710 		svm_range_unlock(prange);
1711 
1712 		addr = next;
1713 	}
1714 
1715 	if (addr == end) {
1716 		prange->validated_once = true;
1717 		prange->mapped_to_gpu = true;
1718 	}
1719 
1720 unreserve_out:
1721 	svm_range_unreserve_bos(ctx);
1722 
1723 	prange->is_error_flag = !!r;
1724 	if (!r)
1725 		prange->validate_timestamp = ktime_get_boottime();
1726 
1727 free_ctx:
1728 	kfree(ctx);
1729 
1730 	return r;
1731 }
1732 
1733 /**
1734  * svm_range_list_lock_and_flush_work - flush pending deferred work
1735  *
1736  * @svms: the svm range list
1737  * @mm: the mm structure
1738  *
1739  * Context: Returns with mmap write lock held, pending deferred work flushed
1740  *
1741  */
1742 void
1743 svm_range_list_lock_and_flush_work(struct svm_range_list *svms,
1744 				   struct mm_struct *mm)
1745 {
1746 retry_flush_work:
1747 	flush_work(&svms->deferred_list_work);
1748 	mmap_write_lock(mm);
1749 
1750 	if (list_empty(&svms->deferred_range_list))
1751 		return;
1752 	mmap_write_unlock(mm);
1753 	pr_debug("retry flush\n");
1754 	goto retry_flush_work;
1755 }
1756 
1757 static void svm_range_restore_work(struct work_struct *work)
1758 {
1759 	struct delayed_work *dwork = to_delayed_work(work);
1760 	struct amdkfd_process_info *process_info;
1761 	struct svm_range_list *svms;
1762 	struct svm_range *prange;
1763 	struct kfd_process *p;
1764 	struct mm_struct *mm;
1765 	int evicted_ranges;
1766 	int invalid;
1767 	int r;
1768 
1769 	svms = container_of(dwork, struct svm_range_list, restore_work);
1770 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1771 	if (!evicted_ranges)
1772 		return;
1773 
1774 	pr_debug("restore svm ranges\n");
1775 
1776 	p = container_of(svms, struct kfd_process, svms);
1777 	process_info = p->kgd_process_info;
1778 
1779 	/* Keep mm reference when svm_range_validate_and_map ranges */
1780 	mm = get_task_mm(p->lead_thread);
1781 	if (!mm) {
1782 		pr_debug("svms 0x%p process mm gone\n", svms);
1783 		return;
1784 	}
1785 
1786 	mutex_lock(&process_info->lock);
1787 	svm_range_list_lock_and_flush_work(svms, mm);
1788 	mutex_lock(&svms->lock);
1789 
1790 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1791 
1792 	list_for_each_entry(prange, &svms->list, list) {
1793 		invalid = atomic_read(&prange->invalid);
1794 		if (!invalid)
1795 			continue;
1796 
1797 		pr_debug("restoring svms 0x%p prange 0x%p [0x%lx %lx] inv %d\n",
1798 			 prange->svms, prange, prange->start, prange->last,
1799 			 invalid);
1800 
1801 		/*
1802 		 * If range is migrating, wait for migration is done.
1803 		 */
1804 		mutex_lock(&prange->migrate_mutex);
1805 
1806 		r = svm_range_validate_and_map(mm, prange, MAX_GPU_INSTANCE,
1807 					       false, true, false);
1808 		if (r)
1809 			pr_debug("failed %d to map 0x%lx to gpus\n", r,
1810 				 prange->start);
1811 
1812 		mutex_unlock(&prange->migrate_mutex);
1813 		if (r)
1814 			goto out_reschedule;
1815 
1816 		if (atomic_cmpxchg(&prange->invalid, invalid, 0) != invalid)
1817 			goto out_reschedule;
1818 	}
1819 
1820 	if (atomic_cmpxchg(&svms->evicted_ranges, evicted_ranges, 0) !=
1821 	    evicted_ranges)
1822 		goto out_reschedule;
1823 
1824 	evicted_ranges = 0;
1825 
1826 	r = kgd2kfd_resume_mm(mm);
1827 	if (r) {
1828 		/* No recovery from this failure. Probably the CP is
1829 		 * hanging. No point trying again.
1830 		 */
1831 		pr_debug("failed %d to resume KFD\n", r);
1832 	}
1833 
1834 	pr_debug("restore svm ranges successfully\n");
1835 
1836 out_reschedule:
1837 	mutex_unlock(&svms->lock);
1838 	mmap_write_unlock(mm);
1839 	mutex_unlock(&process_info->lock);
1840 
1841 	/* If validation failed, reschedule another attempt */
1842 	if (evicted_ranges) {
1843 		pr_debug("reschedule to restore svm range\n");
1844 		schedule_delayed_work(&svms->restore_work,
1845 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1846 
1847 		kfd_smi_event_queue_restore_rescheduled(mm);
1848 	}
1849 	mmput(mm);
1850 }
1851 
1852 /**
1853  * svm_range_evict - evict svm range
1854  * @prange: svm range structure
1855  * @mm: current process mm_struct
1856  * @start: starting process queue number
1857  * @last: last process queue number
1858  * @event: mmu notifier event when range is evicted or migrated
1859  *
1860  * Stop all queues of the process to ensure GPU doesn't access the memory, then
1861  * return to let CPU evict the buffer and proceed CPU pagetable update.
1862  *
1863  * Don't need use lock to sync cpu pagetable invalidation with GPU execution.
1864  * If invalidation happens while restore work is running, restore work will
1865  * restart to ensure to get the latest CPU pages mapping to GPU, then start
1866  * the queues.
1867  */
1868 static int
1869 svm_range_evict(struct svm_range *prange, struct mm_struct *mm,
1870 		unsigned long start, unsigned long last,
1871 		enum mmu_notifier_event event)
1872 {
1873 	struct svm_range_list *svms = prange->svms;
1874 	struct svm_range *pchild;
1875 	struct kfd_process *p;
1876 	int r = 0;
1877 
1878 	p = container_of(svms, struct kfd_process, svms);
1879 
1880 	pr_debug("invalidate svms 0x%p prange [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
1881 		 svms, prange->start, prange->last, start, last);
1882 
1883 	if (!p->xnack_enabled ||
1884 	    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) {
1885 		int evicted_ranges;
1886 		bool mapped = prange->mapped_to_gpu;
1887 
1888 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1889 			if (!pchild->mapped_to_gpu)
1890 				continue;
1891 			mapped = true;
1892 			mutex_lock_nested(&pchild->lock, 1);
1893 			if (pchild->start <= last && pchild->last >= start) {
1894 				pr_debug("increment pchild invalid [0x%lx 0x%lx]\n",
1895 					 pchild->start, pchild->last);
1896 				atomic_inc(&pchild->invalid);
1897 			}
1898 			mutex_unlock(&pchild->lock);
1899 		}
1900 
1901 		if (!mapped)
1902 			return r;
1903 
1904 		if (prange->start <= last && prange->last >= start)
1905 			atomic_inc(&prange->invalid);
1906 
1907 		evicted_ranges = atomic_inc_return(&svms->evicted_ranges);
1908 		if (evicted_ranges != 1)
1909 			return r;
1910 
1911 		pr_debug("evicting svms 0x%p range [0x%lx 0x%lx]\n",
1912 			 prange->svms, prange->start, prange->last);
1913 
1914 		/* First eviction, stop the queues */
1915 		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_SVM);
1916 		if (r)
1917 			pr_debug("failed to quiesce KFD\n");
1918 
1919 		pr_debug("schedule to restore svm %p ranges\n", svms);
1920 		schedule_delayed_work(&svms->restore_work,
1921 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1922 	} else {
1923 		unsigned long s, l;
1924 		uint32_t trigger;
1925 
1926 		if (event == MMU_NOTIFY_MIGRATE)
1927 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY_MIGRATE;
1928 		else
1929 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY;
1930 
1931 		pr_debug("invalidate unmap svms 0x%p [0x%lx 0x%lx] from GPUs\n",
1932 			 prange->svms, start, last);
1933 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1934 			mutex_lock_nested(&pchild->lock, 1);
1935 			s = max(start, pchild->start);
1936 			l = min(last, pchild->last);
1937 			if (l >= s)
1938 				svm_range_unmap_from_gpus(pchild, s, l, trigger);
1939 			mutex_unlock(&pchild->lock);
1940 		}
1941 		s = max(start, prange->start);
1942 		l = min(last, prange->last);
1943 		if (l >= s)
1944 			svm_range_unmap_from_gpus(prange, s, l, trigger);
1945 	}
1946 
1947 	return r;
1948 }
1949 
1950 static struct svm_range *svm_range_clone(struct svm_range *old)
1951 {
1952 	struct svm_range *new;
1953 
1954 	new = svm_range_new(old->svms, old->start, old->last, false);
1955 	if (!new)
1956 		return NULL;
1957 	if (svm_range_copy_dma_addrs(new, old)) {
1958 		svm_range_free(new, false);
1959 		return NULL;
1960 	}
1961 	if (old->svm_bo) {
1962 		new->ttm_res = old->ttm_res;
1963 		new->offset = old->offset;
1964 		new->svm_bo = svm_range_bo_ref(old->svm_bo);
1965 		spin_lock(&new->svm_bo->list_lock);
1966 		list_add(&new->svm_bo_list, &new->svm_bo->range_list);
1967 		spin_unlock(&new->svm_bo->list_lock);
1968 	}
1969 	new->flags = old->flags;
1970 	new->preferred_loc = old->preferred_loc;
1971 	new->prefetch_loc = old->prefetch_loc;
1972 	new->actual_loc = old->actual_loc;
1973 	new->granularity = old->granularity;
1974 	new->mapped_to_gpu = old->mapped_to_gpu;
1975 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
1976 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
1977 
1978 	return new;
1979 }
1980 
1981 void svm_range_set_max_pages(struct amdgpu_device *adev)
1982 {
1983 	uint64_t max_pages;
1984 	uint64_t pages, _pages;
1985 	uint64_t min_pages = 0;
1986 	int i, id;
1987 
1988 	for (i = 0; i < adev->kfd.dev->num_nodes; i++) {
1989 		if (adev->kfd.dev->nodes[i]->xcp)
1990 			id = adev->kfd.dev->nodes[i]->xcp->id;
1991 		else
1992 			id = -1;
1993 		pages = KFD_XCP_MEMORY_SIZE(adev, id) >> 17;
1994 		pages = clamp(pages, 1ULL << 9, 1ULL << 18);
1995 		pages = rounddown_pow_of_two(pages);
1996 		min_pages = min_not_zero(min_pages, pages);
1997 	}
1998 
1999 	do {
2000 		max_pages = READ_ONCE(max_svm_range_pages);
2001 		_pages = min_not_zero(max_pages, min_pages);
2002 	} while (cmpxchg(&max_svm_range_pages, max_pages, _pages) != max_pages);
2003 }
2004 
2005 static int
2006 svm_range_split_new(struct svm_range_list *svms, uint64_t start, uint64_t last,
2007 		    uint64_t max_pages, struct list_head *insert_list,
2008 		    struct list_head *update_list)
2009 {
2010 	struct svm_range *prange;
2011 	uint64_t l;
2012 
2013 	pr_debug("max_svm_range_pages 0x%llx adding [0x%llx 0x%llx]\n",
2014 		 max_pages, start, last);
2015 
2016 	while (last >= start) {
2017 		l = min(last, ALIGN_DOWN(start + max_pages, max_pages) - 1);
2018 
2019 		prange = svm_range_new(svms, start, l, true);
2020 		if (!prange)
2021 			return -ENOMEM;
2022 		list_add(&prange->list, insert_list);
2023 		list_add(&prange->update_list, update_list);
2024 
2025 		start = l + 1;
2026 	}
2027 	return 0;
2028 }
2029 
2030 /**
2031  * svm_range_add - add svm range and handle overlap
2032  * @p: the range add to this process svms
2033  * @start: page size aligned
2034  * @size: page size aligned
2035  * @nattr: number of attributes
2036  * @attrs: array of attributes
2037  * @update_list: output, the ranges need validate and update GPU mapping
2038  * @insert_list: output, the ranges need insert to svms
2039  * @remove_list: output, the ranges are replaced and need remove from svms
2040  *
2041  * Check if the virtual address range has overlap with any existing ranges,
2042  * split partly overlapping ranges and add new ranges in the gaps. All changes
2043  * should be applied to the range_list and interval tree transactionally. If
2044  * any range split or allocation fails, the entire update fails. Therefore any
2045  * existing overlapping svm_ranges are cloned and the original svm_ranges left
2046  * unchanged.
2047  *
2048  * If the transaction succeeds, the caller can update and insert clones and
2049  * new ranges, then free the originals.
2050  *
2051  * Otherwise the caller can free the clones and new ranges, while the old
2052  * svm_ranges remain unchanged.
2053  *
2054  * Context: Process context, caller must hold svms->lock
2055  *
2056  * Return:
2057  * 0 - OK, otherwise error code
2058  */
2059 static int
2060 svm_range_add(struct kfd_process *p, uint64_t start, uint64_t size,
2061 	      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
2062 	      struct list_head *update_list, struct list_head *insert_list,
2063 	      struct list_head *remove_list)
2064 {
2065 	unsigned long last = start + size - 1UL;
2066 	struct svm_range_list *svms = &p->svms;
2067 	struct interval_tree_node *node;
2068 	struct svm_range *prange;
2069 	struct svm_range *tmp;
2070 	struct list_head new_list;
2071 	int r = 0;
2072 
2073 	pr_debug("svms 0x%p [0x%llx 0x%lx]\n", &p->svms, start, last);
2074 
2075 	INIT_LIST_HEAD(update_list);
2076 	INIT_LIST_HEAD(insert_list);
2077 	INIT_LIST_HEAD(remove_list);
2078 	INIT_LIST_HEAD(&new_list);
2079 
2080 	node = interval_tree_iter_first(&svms->objects, start, last);
2081 	while (node) {
2082 		struct interval_tree_node *next;
2083 		unsigned long next_start;
2084 
2085 		pr_debug("found overlap node [0x%lx 0x%lx]\n", node->start,
2086 			 node->last);
2087 
2088 		prange = container_of(node, struct svm_range, it_node);
2089 		next = interval_tree_iter_next(node, start, last);
2090 		next_start = min(node->last, last) + 1;
2091 
2092 		if (svm_range_is_same_attrs(p, prange, nattr, attrs)) {
2093 			/* nothing to do */
2094 		} else if (node->start < start || node->last > last) {
2095 			/* node intersects the update range and its attributes
2096 			 * will change. Clone and split it, apply updates only
2097 			 * to the overlapping part
2098 			 */
2099 			struct svm_range *old = prange;
2100 
2101 			prange = svm_range_clone(old);
2102 			if (!prange) {
2103 				r = -ENOMEM;
2104 				goto out;
2105 			}
2106 
2107 			list_add(&old->update_list, remove_list);
2108 			list_add(&prange->list, insert_list);
2109 			list_add(&prange->update_list, update_list);
2110 
2111 			if (node->start < start) {
2112 				pr_debug("change old range start\n");
2113 				r = svm_range_split_head(prange, start,
2114 							 insert_list);
2115 				if (r)
2116 					goto out;
2117 			}
2118 			if (node->last > last) {
2119 				pr_debug("change old range last\n");
2120 				r = svm_range_split_tail(prange, last,
2121 							 insert_list);
2122 				if (r)
2123 					goto out;
2124 			}
2125 		} else {
2126 			/* The node is contained within start..last,
2127 			 * just update it
2128 			 */
2129 			list_add(&prange->update_list, update_list);
2130 		}
2131 
2132 		/* insert a new node if needed */
2133 		if (node->start > start) {
2134 			r = svm_range_split_new(svms, start, node->start - 1,
2135 						READ_ONCE(max_svm_range_pages),
2136 						&new_list, update_list);
2137 			if (r)
2138 				goto out;
2139 		}
2140 
2141 		node = next;
2142 		start = next_start;
2143 	}
2144 
2145 	/* add a final range at the end if needed */
2146 	if (start <= last)
2147 		r = svm_range_split_new(svms, start, last,
2148 					READ_ONCE(max_svm_range_pages),
2149 					&new_list, update_list);
2150 
2151 out:
2152 	if (r) {
2153 		list_for_each_entry_safe(prange, tmp, insert_list, list)
2154 			svm_range_free(prange, false);
2155 		list_for_each_entry_safe(prange, tmp, &new_list, list)
2156 			svm_range_free(prange, true);
2157 	} else {
2158 		list_splice(&new_list, insert_list);
2159 	}
2160 
2161 	return r;
2162 }
2163 
2164 static void
2165 svm_range_update_notifier_and_interval_tree(struct mm_struct *mm,
2166 					    struct svm_range *prange)
2167 {
2168 	unsigned long start;
2169 	unsigned long last;
2170 
2171 	start = prange->notifier.interval_tree.start >> PAGE_SHIFT;
2172 	last = prange->notifier.interval_tree.last >> PAGE_SHIFT;
2173 
2174 	if (prange->start == start && prange->last == last)
2175 		return;
2176 
2177 	pr_debug("up notifier 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
2178 		  prange->svms, prange, start, last, prange->start,
2179 		  prange->last);
2180 
2181 	if (start != 0 && last != 0) {
2182 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
2183 		svm_range_remove_notifier(prange);
2184 	}
2185 	prange->it_node.start = prange->start;
2186 	prange->it_node.last = prange->last;
2187 
2188 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
2189 	svm_range_add_notifier_locked(mm, prange);
2190 }
2191 
2192 static void
2193 svm_range_handle_list_op(struct svm_range_list *svms, struct svm_range *prange,
2194 			 struct mm_struct *mm)
2195 {
2196 	switch (prange->work_item.op) {
2197 	case SVM_OP_NULL:
2198 		pr_debug("NULL OP 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2199 			 svms, prange, prange->start, prange->last);
2200 		break;
2201 	case SVM_OP_UNMAP_RANGE:
2202 		pr_debug("remove 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2203 			 svms, prange, prange->start, prange->last);
2204 		svm_range_unlink(prange);
2205 		svm_range_remove_notifier(prange);
2206 		svm_range_free(prange, true);
2207 		break;
2208 	case SVM_OP_UPDATE_RANGE_NOTIFIER:
2209 		pr_debug("update notifier 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2210 			 svms, prange, prange->start, prange->last);
2211 		svm_range_update_notifier_and_interval_tree(mm, prange);
2212 		break;
2213 	case SVM_OP_UPDATE_RANGE_NOTIFIER_AND_MAP:
2214 		pr_debug("update and map 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2215 			 svms, prange, prange->start, prange->last);
2216 		svm_range_update_notifier_and_interval_tree(mm, prange);
2217 		/* TODO: implement deferred validation and mapping */
2218 		break;
2219 	case SVM_OP_ADD_RANGE:
2220 		pr_debug("add 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms, prange,
2221 			 prange->start, prange->last);
2222 		svm_range_add_to_svms(prange);
2223 		svm_range_add_notifier_locked(mm, prange);
2224 		break;
2225 	case SVM_OP_ADD_RANGE_AND_MAP:
2226 		pr_debug("add and map 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms,
2227 			 prange, prange->start, prange->last);
2228 		svm_range_add_to_svms(prange);
2229 		svm_range_add_notifier_locked(mm, prange);
2230 		/* TODO: implement deferred validation and mapping */
2231 		break;
2232 	default:
2233 		WARN_ONCE(1, "Unknown prange 0x%p work op %d\n", prange,
2234 			 prange->work_item.op);
2235 	}
2236 }
2237 
2238 static void svm_range_drain_retry_fault(struct svm_range_list *svms)
2239 {
2240 	struct kfd_process_device *pdd;
2241 	struct kfd_process *p;
2242 	int drain;
2243 	uint32_t i;
2244 
2245 	p = container_of(svms, struct kfd_process, svms);
2246 
2247 restart:
2248 	drain = atomic_read(&svms->drain_pagefaults);
2249 	if (!drain)
2250 		return;
2251 
2252 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2253 		pdd = p->pdds[i];
2254 		if (!pdd)
2255 			continue;
2256 
2257 		pr_debug("drain retry fault gpu %d svms %p\n", i, svms);
2258 
2259 		amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2260 				pdd->dev->adev->irq.retry_cam_enabled ?
2261 				&pdd->dev->adev->irq.ih :
2262 				&pdd->dev->adev->irq.ih1);
2263 
2264 		if (pdd->dev->adev->irq.retry_cam_enabled)
2265 			amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2266 				&pdd->dev->adev->irq.ih_soft);
2267 
2268 
2269 		pr_debug("drain retry fault gpu %d svms 0x%p done\n", i, svms);
2270 	}
2271 	if (atomic_cmpxchg(&svms->drain_pagefaults, drain, 0) != drain)
2272 		goto restart;
2273 }
2274 
2275 static void svm_range_deferred_list_work(struct work_struct *work)
2276 {
2277 	struct svm_range_list *svms;
2278 	struct svm_range *prange;
2279 	struct mm_struct *mm;
2280 
2281 	svms = container_of(work, struct svm_range_list, deferred_list_work);
2282 	pr_debug("enter svms 0x%p\n", svms);
2283 
2284 	spin_lock(&svms->deferred_list_lock);
2285 	while (!list_empty(&svms->deferred_range_list)) {
2286 		prange = list_first_entry(&svms->deferred_range_list,
2287 					  struct svm_range, deferred_list);
2288 		spin_unlock(&svms->deferred_list_lock);
2289 
2290 		pr_debug("prange 0x%p [0x%lx 0x%lx] op %d\n", prange,
2291 			 prange->start, prange->last, prange->work_item.op);
2292 
2293 		mm = prange->work_item.mm;
2294 retry:
2295 		mmap_write_lock(mm);
2296 
2297 		/* Checking for the need to drain retry faults must be inside
2298 		 * mmap write lock to serialize with munmap notifiers.
2299 		 */
2300 		if (unlikely(atomic_read(&svms->drain_pagefaults))) {
2301 			mmap_write_unlock(mm);
2302 			svm_range_drain_retry_fault(svms);
2303 			goto retry;
2304 		}
2305 
2306 		/* Remove from deferred_list must be inside mmap write lock, for
2307 		 * two race cases:
2308 		 * 1. unmap_from_cpu may change work_item.op and add the range
2309 		 *    to deferred_list again, cause use after free bug.
2310 		 * 2. svm_range_list_lock_and_flush_work may hold mmap write
2311 		 *    lock and continue because deferred_list is empty, but
2312 		 *    deferred_list work is actually waiting for mmap lock.
2313 		 */
2314 		spin_lock(&svms->deferred_list_lock);
2315 		list_del_init(&prange->deferred_list);
2316 		spin_unlock(&svms->deferred_list_lock);
2317 
2318 		mutex_lock(&svms->lock);
2319 		mutex_lock(&prange->migrate_mutex);
2320 		while (!list_empty(&prange->child_list)) {
2321 			struct svm_range *pchild;
2322 
2323 			pchild = list_first_entry(&prange->child_list,
2324 						struct svm_range, child_list);
2325 			pr_debug("child prange 0x%p op %d\n", pchild,
2326 				 pchild->work_item.op);
2327 			list_del_init(&pchild->child_list);
2328 			svm_range_handle_list_op(svms, pchild, mm);
2329 		}
2330 		mutex_unlock(&prange->migrate_mutex);
2331 
2332 		svm_range_handle_list_op(svms, prange, mm);
2333 		mutex_unlock(&svms->lock);
2334 		mmap_write_unlock(mm);
2335 
2336 		/* Pairs with mmget in svm_range_add_list_work */
2337 		mmput(mm);
2338 
2339 		spin_lock(&svms->deferred_list_lock);
2340 	}
2341 	spin_unlock(&svms->deferred_list_lock);
2342 	pr_debug("exit svms 0x%p\n", svms);
2343 }
2344 
2345 void
2346 svm_range_add_list_work(struct svm_range_list *svms, struct svm_range *prange,
2347 			struct mm_struct *mm, enum svm_work_list_ops op)
2348 {
2349 	spin_lock(&svms->deferred_list_lock);
2350 	/* if prange is on the deferred list */
2351 	if (!list_empty(&prange->deferred_list)) {
2352 		pr_debug("update exist prange 0x%p work op %d\n", prange, op);
2353 		WARN_ONCE(prange->work_item.mm != mm, "unmatch mm\n");
2354 		if (op != SVM_OP_NULL &&
2355 		    prange->work_item.op != SVM_OP_UNMAP_RANGE)
2356 			prange->work_item.op = op;
2357 	} else {
2358 		prange->work_item.op = op;
2359 
2360 		/* Pairs with mmput in deferred_list_work */
2361 		mmget(mm);
2362 		prange->work_item.mm = mm;
2363 		list_add_tail(&prange->deferred_list,
2364 			      &prange->svms->deferred_range_list);
2365 		pr_debug("add prange 0x%p [0x%lx 0x%lx] to work list op %d\n",
2366 			 prange, prange->start, prange->last, op);
2367 	}
2368 	spin_unlock(&svms->deferred_list_lock);
2369 }
2370 
2371 void schedule_deferred_list_work(struct svm_range_list *svms)
2372 {
2373 	spin_lock(&svms->deferred_list_lock);
2374 	if (!list_empty(&svms->deferred_range_list))
2375 		schedule_work(&svms->deferred_list_work);
2376 	spin_unlock(&svms->deferred_list_lock);
2377 }
2378 
2379 static void
2380 svm_range_unmap_split(struct mm_struct *mm, struct svm_range *parent,
2381 		      struct svm_range *prange, unsigned long start,
2382 		      unsigned long last)
2383 {
2384 	struct svm_range *head;
2385 	struct svm_range *tail;
2386 
2387 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2388 		pr_debug("prange 0x%p [0x%lx 0x%lx] is already freed\n", prange,
2389 			 prange->start, prange->last);
2390 		return;
2391 	}
2392 	if (start > prange->last || last < prange->start)
2393 		return;
2394 
2395 	head = tail = prange;
2396 	if (start > prange->start)
2397 		svm_range_split(prange, prange->start, start - 1, &tail);
2398 	if (last < tail->last)
2399 		svm_range_split(tail, last + 1, tail->last, &head);
2400 
2401 	if (head != prange && tail != prange) {
2402 		svm_range_add_child(parent, mm, head, SVM_OP_UNMAP_RANGE);
2403 		svm_range_add_child(parent, mm, tail, SVM_OP_ADD_RANGE);
2404 	} else if (tail != prange) {
2405 		svm_range_add_child(parent, mm, tail, SVM_OP_UNMAP_RANGE);
2406 	} else if (head != prange) {
2407 		svm_range_add_child(parent, mm, head, SVM_OP_UNMAP_RANGE);
2408 	} else if (parent != prange) {
2409 		prange->work_item.op = SVM_OP_UNMAP_RANGE;
2410 	}
2411 }
2412 
2413 static void
2414 svm_range_unmap_from_cpu(struct mm_struct *mm, struct svm_range *prange,
2415 			 unsigned long start, unsigned long last)
2416 {
2417 	uint32_t trigger = KFD_SVM_UNMAP_TRIGGER_UNMAP_FROM_CPU;
2418 	struct svm_range_list *svms;
2419 	struct svm_range *pchild;
2420 	struct kfd_process *p;
2421 	unsigned long s, l;
2422 	bool unmap_parent;
2423 
2424 	p = kfd_lookup_process_by_mm(mm);
2425 	if (!p)
2426 		return;
2427 	svms = &p->svms;
2428 
2429 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n", svms,
2430 		 prange, prange->start, prange->last, start, last);
2431 
2432 	/* Make sure pending page faults are drained in the deferred worker
2433 	 * before the range is freed to avoid straggler interrupts on
2434 	 * unmapped memory causing "phantom faults".
2435 	 */
2436 	atomic_inc(&svms->drain_pagefaults);
2437 
2438 	unmap_parent = start <= prange->start && last >= prange->last;
2439 
2440 	list_for_each_entry(pchild, &prange->child_list, child_list) {
2441 		mutex_lock_nested(&pchild->lock, 1);
2442 		s = max(start, pchild->start);
2443 		l = min(last, pchild->last);
2444 		if (l >= s)
2445 			svm_range_unmap_from_gpus(pchild, s, l, trigger);
2446 		svm_range_unmap_split(mm, prange, pchild, start, last);
2447 		mutex_unlock(&pchild->lock);
2448 	}
2449 	s = max(start, prange->start);
2450 	l = min(last, prange->last);
2451 	if (l >= s)
2452 		svm_range_unmap_from_gpus(prange, s, l, trigger);
2453 	svm_range_unmap_split(mm, prange, prange, start, last);
2454 
2455 	if (unmap_parent)
2456 		svm_range_add_list_work(svms, prange, mm, SVM_OP_UNMAP_RANGE);
2457 	else
2458 		svm_range_add_list_work(svms, prange, mm,
2459 					SVM_OP_UPDATE_RANGE_NOTIFIER);
2460 	schedule_deferred_list_work(svms);
2461 
2462 	kfd_unref_process(p);
2463 }
2464 
2465 /**
2466  * svm_range_cpu_invalidate_pagetables - interval notifier callback
2467  * @mni: mmu_interval_notifier struct
2468  * @range: mmu_notifier_range struct
2469  * @cur_seq: value to pass to mmu_interval_set_seq()
2470  *
2471  * If event is MMU_NOTIFY_UNMAP, this is from CPU unmap range, otherwise, it
2472  * is from migration, or CPU page invalidation callback.
2473  *
2474  * For unmap event, unmap range from GPUs, remove prange from svms in a delayed
2475  * work thread, and split prange if only part of prange is unmapped.
2476  *
2477  * For invalidation event, if GPU retry fault is not enabled, evict the queues,
2478  * then schedule svm_range_restore_work to update GPU mapping and resume queues.
2479  * If GPU retry fault is enabled, unmap the svm range from GPU, retry fault will
2480  * update GPU mapping to recover.
2481  *
2482  * Context: mmap lock, notifier_invalidate_start lock are held
2483  *          for invalidate event, prange lock is held if this is from migration
2484  */
2485 static bool
2486 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
2487 				    const struct mmu_notifier_range *range,
2488 				    unsigned long cur_seq)
2489 {
2490 	struct svm_range *prange;
2491 	unsigned long start;
2492 	unsigned long last;
2493 
2494 	if (range->event == MMU_NOTIFY_RELEASE)
2495 		return true;
2496 	if (!mmget_not_zero(mni->mm))
2497 		return true;
2498 
2499 	start = mni->interval_tree.start;
2500 	last = mni->interval_tree.last;
2501 	start = max(start, range->start) >> PAGE_SHIFT;
2502 	last = min(last, range->end - 1) >> PAGE_SHIFT;
2503 	pr_debug("[0x%lx 0x%lx] range[0x%lx 0x%lx] notifier[0x%lx 0x%lx] %d\n",
2504 		 start, last, range->start >> PAGE_SHIFT,
2505 		 (range->end - 1) >> PAGE_SHIFT,
2506 		 mni->interval_tree.start >> PAGE_SHIFT,
2507 		 mni->interval_tree.last >> PAGE_SHIFT, range->event);
2508 
2509 	prange = container_of(mni, struct svm_range, notifier);
2510 
2511 	svm_range_lock(prange);
2512 	mmu_interval_set_seq(mni, cur_seq);
2513 
2514 	switch (range->event) {
2515 	case MMU_NOTIFY_UNMAP:
2516 		svm_range_unmap_from_cpu(mni->mm, prange, start, last);
2517 		break;
2518 	default:
2519 		svm_range_evict(prange, mni->mm, start, last, range->event);
2520 		break;
2521 	}
2522 
2523 	svm_range_unlock(prange);
2524 	mmput(mni->mm);
2525 
2526 	return true;
2527 }
2528 
2529 /**
2530  * svm_range_from_addr - find svm range from fault address
2531  * @svms: svm range list header
2532  * @addr: address to search range interval tree, in pages
2533  * @parent: parent range if range is on child list
2534  *
2535  * Context: The caller must hold svms->lock
2536  *
2537  * Return: the svm_range found or NULL
2538  */
2539 struct svm_range *
2540 svm_range_from_addr(struct svm_range_list *svms, unsigned long addr,
2541 		    struct svm_range **parent)
2542 {
2543 	struct interval_tree_node *node;
2544 	struct svm_range *prange;
2545 	struct svm_range *pchild;
2546 
2547 	node = interval_tree_iter_first(&svms->objects, addr, addr);
2548 	if (!node)
2549 		return NULL;
2550 
2551 	prange = container_of(node, struct svm_range, it_node);
2552 	pr_debug("address 0x%lx prange [0x%lx 0x%lx] node [0x%lx 0x%lx]\n",
2553 		 addr, prange->start, prange->last, node->start, node->last);
2554 
2555 	if (addr >= prange->start && addr <= prange->last) {
2556 		if (parent)
2557 			*parent = prange;
2558 		return prange;
2559 	}
2560 	list_for_each_entry(pchild, &prange->child_list, child_list)
2561 		if (addr >= pchild->start && addr <= pchild->last) {
2562 			pr_debug("found address 0x%lx pchild [0x%lx 0x%lx]\n",
2563 				 addr, pchild->start, pchild->last);
2564 			if (parent)
2565 				*parent = prange;
2566 			return pchild;
2567 		}
2568 
2569 	return NULL;
2570 }
2571 
2572 /* svm_range_best_restore_location - decide the best fault restore location
2573  * @prange: svm range structure
2574  * @adev: the GPU on which vm fault happened
2575  *
2576  * This is only called when xnack is on, to decide the best location to restore
2577  * the range mapping after GPU vm fault. Caller uses the best location to do
2578  * migration if actual loc is not best location, then update GPU page table
2579  * mapping to the best location.
2580  *
2581  * If the preferred loc is accessible by faulting GPU, use preferred loc.
2582  * If vm fault gpu idx is on range ACCESSIBLE bitmap, best_loc is vm fault gpu
2583  * If vm fault gpu idx is on range ACCESSIBLE_IN_PLACE bitmap, then
2584  *    if range actual loc is cpu, best_loc is cpu
2585  *    if vm fault gpu is on xgmi same hive of range actual loc gpu, best_loc is
2586  *    range actual loc.
2587  * Otherwise, GPU no access, best_loc is -1.
2588  *
2589  * Return:
2590  * -1 means vm fault GPU no access
2591  * 0 for CPU or GPU id
2592  */
2593 static int32_t
2594 svm_range_best_restore_location(struct svm_range *prange,
2595 				struct kfd_node *node,
2596 				int32_t *gpuidx)
2597 {
2598 	struct kfd_node *bo_node, *preferred_node;
2599 	struct kfd_process *p;
2600 	uint32_t gpuid;
2601 	int r;
2602 
2603 	p = container_of(prange->svms, struct kfd_process, svms);
2604 
2605 	r = kfd_process_gpuid_from_node(p, node, &gpuid, gpuidx);
2606 	if (r < 0) {
2607 		pr_debug("failed to get gpuid from kgd\n");
2608 		return -1;
2609 	}
2610 
2611 	if (node->adev->gmc.is_app_apu)
2612 		return 0;
2613 
2614 	if (prange->preferred_loc == gpuid ||
2615 	    prange->preferred_loc == KFD_IOCTL_SVM_LOCATION_SYSMEM) {
2616 		return prange->preferred_loc;
2617 	} else if (prange->preferred_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
2618 		preferred_node = svm_range_get_node_by_id(prange, prange->preferred_loc);
2619 		if (preferred_node && svm_nodes_in_same_hive(node, preferred_node))
2620 			return prange->preferred_loc;
2621 		/* fall through */
2622 	}
2623 
2624 	if (test_bit(*gpuidx, prange->bitmap_access))
2625 		return gpuid;
2626 
2627 	if (test_bit(*gpuidx, prange->bitmap_aip)) {
2628 		if (!prange->actual_loc)
2629 			return 0;
2630 
2631 		bo_node = svm_range_get_node_by_id(prange, prange->actual_loc);
2632 		if (bo_node && svm_nodes_in_same_hive(node, bo_node))
2633 			return prange->actual_loc;
2634 		else
2635 			return 0;
2636 	}
2637 
2638 	return -1;
2639 }
2640 
2641 static int
2642 svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
2643 			       unsigned long *start, unsigned long *last,
2644 			       bool *is_heap_stack)
2645 {
2646 	struct vm_area_struct *vma;
2647 	struct interval_tree_node *node;
2648 	unsigned long start_limit, end_limit;
2649 
2650 	vma = vma_lookup(p->mm, addr << PAGE_SHIFT);
2651 	if (!vma) {
2652 		pr_debug("VMA does not exist in address [0x%llx]\n", addr);
2653 		return -EFAULT;
2654 	}
2655 
2656 	*is_heap_stack = (vma->vm_start <= vma->vm_mm->brk &&
2657 			  vma->vm_end >= vma->vm_mm->start_brk) ||
2658 			 (vma->vm_start <= vma->vm_mm->start_stack &&
2659 			  vma->vm_end >= vma->vm_mm->start_stack);
2660 
2661 	start_limit = max(vma->vm_start >> PAGE_SHIFT,
2662 		      (unsigned long)ALIGN_DOWN(addr, 2UL << 8));
2663 	end_limit = min(vma->vm_end >> PAGE_SHIFT,
2664 		    (unsigned long)ALIGN(addr + 1, 2UL << 8));
2665 	/* First range that starts after the fault address */
2666 	node = interval_tree_iter_first(&p->svms.objects, addr + 1, ULONG_MAX);
2667 	if (node) {
2668 		end_limit = min(end_limit, node->start);
2669 		/* Last range that ends before the fault address */
2670 		node = container_of(rb_prev(&node->rb),
2671 				    struct interval_tree_node, rb);
2672 	} else {
2673 		/* Last range must end before addr because
2674 		 * there was no range after addr
2675 		 */
2676 		node = container_of(rb_last(&p->svms.objects.rb_root),
2677 				    struct interval_tree_node, rb);
2678 	}
2679 	if (node) {
2680 		if (node->last >= addr) {
2681 			WARN(1, "Overlap with prev node and page fault addr\n");
2682 			return -EFAULT;
2683 		}
2684 		start_limit = max(start_limit, node->last + 1);
2685 	}
2686 
2687 	*start = start_limit;
2688 	*last = end_limit - 1;
2689 
2690 	pr_debug("vma [0x%lx 0x%lx] range [0x%lx 0x%lx] is_heap_stack %d\n",
2691 		 vma->vm_start >> PAGE_SHIFT, vma->vm_end >> PAGE_SHIFT,
2692 		 *start, *last, *is_heap_stack);
2693 
2694 	return 0;
2695 }
2696 
2697 static int
2698 svm_range_check_vm_userptr(struct kfd_process *p, uint64_t start, uint64_t last,
2699 			   uint64_t *bo_s, uint64_t *bo_l)
2700 {
2701 	struct amdgpu_bo_va_mapping *mapping;
2702 	struct interval_tree_node *node;
2703 	struct amdgpu_bo *bo = NULL;
2704 	unsigned long userptr;
2705 	uint32_t i;
2706 	int r;
2707 
2708 	for (i = 0; i < p->n_pdds; i++) {
2709 		struct amdgpu_vm *vm;
2710 
2711 		if (!p->pdds[i]->drm_priv)
2712 			continue;
2713 
2714 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
2715 		r = amdgpu_bo_reserve(vm->root.bo, false);
2716 		if (r)
2717 			return r;
2718 
2719 		/* Check userptr by searching entire vm->va interval tree */
2720 		node = interval_tree_iter_first(&vm->va, 0, ~0ULL);
2721 		while (node) {
2722 			mapping = container_of((struct rb_node *)node,
2723 					       struct amdgpu_bo_va_mapping, rb);
2724 			bo = mapping->bo_va->base.bo;
2725 
2726 			if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm,
2727 							 start << PAGE_SHIFT,
2728 							 last << PAGE_SHIFT,
2729 							 &userptr)) {
2730 				node = interval_tree_iter_next(node, 0, ~0ULL);
2731 				continue;
2732 			}
2733 
2734 			pr_debug("[0x%llx 0x%llx] already userptr mapped\n",
2735 				 start, last);
2736 			if (bo_s && bo_l) {
2737 				*bo_s = userptr >> PAGE_SHIFT;
2738 				*bo_l = *bo_s + bo->tbo.ttm->num_pages - 1;
2739 			}
2740 			amdgpu_bo_unreserve(vm->root.bo);
2741 			return -EADDRINUSE;
2742 		}
2743 		amdgpu_bo_unreserve(vm->root.bo);
2744 	}
2745 	return 0;
2746 }
2747 
2748 static struct
2749 svm_range *svm_range_create_unregistered_range(struct kfd_node *node,
2750 						struct kfd_process *p,
2751 						struct mm_struct *mm,
2752 						int64_t addr)
2753 {
2754 	struct svm_range *prange = NULL;
2755 	unsigned long start, last;
2756 	uint32_t gpuid, gpuidx;
2757 	bool is_heap_stack;
2758 	uint64_t bo_s = 0;
2759 	uint64_t bo_l = 0;
2760 	int r;
2761 
2762 	if (svm_range_get_range_boundaries(p, addr, &start, &last,
2763 					   &is_heap_stack))
2764 		return NULL;
2765 
2766 	r = svm_range_check_vm(p, start, last, &bo_s, &bo_l);
2767 	if (r != -EADDRINUSE)
2768 		r = svm_range_check_vm_userptr(p, start, last, &bo_s, &bo_l);
2769 
2770 	if (r == -EADDRINUSE) {
2771 		if (addr >= bo_s && addr <= bo_l)
2772 			return NULL;
2773 
2774 		/* Create one page svm range if 2MB range overlapping */
2775 		start = addr;
2776 		last = addr;
2777 	}
2778 
2779 	prange = svm_range_new(&p->svms, start, last, true);
2780 	if (!prange) {
2781 		pr_debug("Failed to create prange in address [0x%llx]\n", addr);
2782 		return NULL;
2783 	}
2784 	if (kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx)) {
2785 		pr_debug("failed to get gpuid from kgd\n");
2786 		svm_range_free(prange, true);
2787 		return NULL;
2788 	}
2789 
2790 	if (is_heap_stack)
2791 		prange->preferred_loc = KFD_IOCTL_SVM_LOCATION_SYSMEM;
2792 
2793 	svm_range_add_to_svms(prange);
2794 	svm_range_add_notifier_locked(mm, prange);
2795 
2796 	return prange;
2797 }
2798 
2799 /* svm_range_skip_recover - decide if prange can be recovered
2800  * @prange: svm range structure
2801  *
2802  * GPU vm retry fault handle skip recover the range for cases:
2803  * 1. prange is on deferred list to be removed after unmap, it is stale fault,
2804  *    deferred list work will drain the stale fault before free the prange.
2805  * 2. prange is on deferred list to add interval notifier after split, or
2806  * 3. prange is child range, it is split from parent prange, recover later
2807  *    after interval notifier is added.
2808  *
2809  * Return: true to skip recover, false to recover
2810  */
2811 static bool svm_range_skip_recover(struct svm_range *prange)
2812 {
2813 	struct svm_range_list *svms = prange->svms;
2814 
2815 	spin_lock(&svms->deferred_list_lock);
2816 	if (list_empty(&prange->deferred_list) &&
2817 	    list_empty(&prange->child_list)) {
2818 		spin_unlock(&svms->deferred_list_lock);
2819 		return false;
2820 	}
2821 	spin_unlock(&svms->deferred_list_lock);
2822 
2823 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2824 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] unmapped\n",
2825 			 svms, prange, prange->start, prange->last);
2826 		return true;
2827 	}
2828 	if (prange->work_item.op == SVM_OP_ADD_RANGE_AND_MAP ||
2829 	    prange->work_item.op == SVM_OP_ADD_RANGE) {
2830 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] not added yet\n",
2831 			 svms, prange, prange->start, prange->last);
2832 		return true;
2833 	}
2834 	return false;
2835 }
2836 
2837 static void
2838 svm_range_count_fault(struct kfd_node *node, struct kfd_process *p,
2839 		      int32_t gpuidx)
2840 {
2841 	struct kfd_process_device *pdd;
2842 
2843 	/* fault is on different page of same range
2844 	 * or fault is skipped to recover later
2845 	 * or fault is on invalid virtual address
2846 	 */
2847 	if (gpuidx == MAX_GPU_INSTANCE) {
2848 		uint32_t gpuid;
2849 		int r;
2850 
2851 		r = kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx);
2852 		if (r < 0)
2853 			return;
2854 	}
2855 
2856 	/* fault is recovered
2857 	 * or fault cannot recover because GPU no access on the range
2858 	 */
2859 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
2860 	if (pdd)
2861 		WRITE_ONCE(pdd->faults, pdd->faults + 1);
2862 }
2863 
2864 static bool
2865 svm_fault_allowed(struct vm_area_struct *vma, bool write_fault)
2866 {
2867 	unsigned long requested = VM_READ;
2868 
2869 	if (write_fault)
2870 		requested |= VM_WRITE;
2871 
2872 	pr_debug("requested 0x%lx, vma permission flags 0x%lx\n", requested,
2873 		vma->vm_flags);
2874 	return (vma->vm_flags & requested) == requested;
2875 }
2876 
2877 int
2878 svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
2879 			uint32_t vmid, uint32_t node_id,
2880 			uint64_t addr, bool write_fault)
2881 {
2882 	struct mm_struct *mm = NULL;
2883 	struct svm_range_list *svms;
2884 	struct svm_range *prange;
2885 	struct kfd_process *p;
2886 	ktime_t timestamp = ktime_get_boottime();
2887 	struct kfd_node *node;
2888 	int32_t best_loc;
2889 	int32_t gpuidx = MAX_GPU_INSTANCE;
2890 	bool write_locked = false;
2891 	struct vm_area_struct *vma;
2892 	bool migration = false;
2893 	int r = 0;
2894 
2895 	if (!KFD_IS_SVM_API_SUPPORTED(adev)) {
2896 		pr_debug("device does not support SVM\n");
2897 		return -EFAULT;
2898 	}
2899 
2900 	p = kfd_lookup_process_by_pasid(pasid);
2901 	if (!p) {
2902 		pr_debug("kfd process not founded pasid 0x%x\n", pasid);
2903 		return 0;
2904 	}
2905 	svms = &p->svms;
2906 
2907 	pr_debug("restoring svms 0x%p fault address 0x%llx\n", svms, addr);
2908 
2909 	if (atomic_read(&svms->drain_pagefaults)) {
2910 		pr_debug("draining retry fault, drop fault 0x%llx\n", addr);
2911 		r = 0;
2912 		goto out;
2913 	}
2914 
2915 	if (!p->xnack_enabled) {
2916 		pr_debug("XNACK not enabled for pasid 0x%x\n", pasid);
2917 		r = -EFAULT;
2918 		goto out;
2919 	}
2920 
2921 	/* p->lead_thread is available as kfd_process_wq_release flush the work
2922 	 * before releasing task ref.
2923 	 */
2924 	mm = get_task_mm(p->lead_thread);
2925 	if (!mm) {
2926 		pr_debug("svms 0x%p failed to get mm\n", svms);
2927 		r = 0;
2928 		goto out;
2929 	}
2930 
2931 	node = kfd_node_by_irq_ids(adev, node_id, vmid);
2932 	if (!node) {
2933 		pr_debug("kfd node does not exist node_id: %d, vmid: %d\n", node_id,
2934 			 vmid);
2935 		r = -EFAULT;
2936 		goto out;
2937 	}
2938 	mmap_read_lock(mm);
2939 retry_write_locked:
2940 	mutex_lock(&svms->lock);
2941 	prange = svm_range_from_addr(svms, addr, NULL);
2942 	if (!prange) {
2943 		pr_debug("failed to find prange svms 0x%p address [0x%llx]\n",
2944 			 svms, addr);
2945 		if (!write_locked) {
2946 			/* Need the write lock to create new range with MMU notifier.
2947 			 * Also flush pending deferred work to make sure the interval
2948 			 * tree is up to date before we add a new range
2949 			 */
2950 			mutex_unlock(&svms->lock);
2951 			mmap_read_unlock(mm);
2952 			mmap_write_lock(mm);
2953 			write_locked = true;
2954 			goto retry_write_locked;
2955 		}
2956 		prange = svm_range_create_unregistered_range(node, p, mm, addr);
2957 		if (!prange) {
2958 			pr_debug("failed to create unregistered range svms 0x%p address [0x%llx]\n",
2959 				 svms, addr);
2960 			mmap_write_downgrade(mm);
2961 			r = -EFAULT;
2962 			goto out_unlock_svms;
2963 		}
2964 	}
2965 	if (write_locked)
2966 		mmap_write_downgrade(mm);
2967 
2968 	mutex_lock(&prange->migrate_mutex);
2969 
2970 	if (svm_range_skip_recover(prange)) {
2971 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
2972 		r = 0;
2973 		goto out_unlock_range;
2974 	}
2975 
2976 	/* skip duplicate vm fault on different pages of same range */
2977 	if (ktime_before(timestamp, ktime_add_ns(prange->validate_timestamp,
2978 				AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING))) {
2979 		pr_debug("svms 0x%p [0x%lx %lx] already restored\n",
2980 			 svms, prange->start, prange->last);
2981 		r = 0;
2982 		goto out_unlock_range;
2983 	}
2984 
2985 	/* __do_munmap removed VMA, return success as we are handling stale
2986 	 * retry fault.
2987 	 */
2988 	vma = vma_lookup(mm, addr << PAGE_SHIFT);
2989 	if (!vma) {
2990 		pr_debug("address 0x%llx VMA is removed\n", addr);
2991 		r = 0;
2992 		goto out_unlock_range;
2993 	}
2994 
2995 	if (!svm_fault_allowed(vma, write_fault)) {
2996 		pr_debug("fault addr 0x%llx no %s permission\n", addr,
2997 			write_fault ? "write" : "read");
2998 		r = -EPERM;
2999 		goto out_unlock_range;
3000 	}
3001 
3002 	best_loc = svm_range_best_restore_location(prange, node, &gpuidx);
3003 	if (best_loc == -1) {
3004 		pr_debug("svms %p failed get best restore loc [0x%lx 0x%lx]\n",
3005 			 svms, prange->start, prange->last);
3006 		r = -EACCES;
3007 		goto out_unlock_range;
3008 	}
3009 
3010 	pr_debug("svms %p [0x%lx 0x%lx] best restore 0x%x, actual loc 0x%x\n",
3011 		 svms, prange->start, prange->last, best_loc,
3012 		 prange->actual_loc);
3013 
3014 	kfd_smi_event_page_fault_start(node, p->lead_thread->pid, addr,
3015 				       write_fault, timestamp);
3016 
3017 	if (prange->actual_loc != best_loc) {
3018 		migration = true;
3019 		if (best_loc) {
3020 			r = svm_migrate_to_vram(prange, best_loc, mm,
3021 					KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU);
3022 			if (r) {
3023 				pr_debug("svm_migrate_to_vram failed (%d) at %llx, falling back to system memory\n",
3024 					 r, addr);
3025 				/* Fallback to system memory if migration to
3026 				 * VRAM failed
3027 				 */
3028 				if (prange->actual_loc)
3029 					r = svm_migrate_vram_to_ram(prange, mm,
3030 					   KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU,
3031 					   NULL);
3032 				else
3033 					r = 0;
3034 			}
3035 		} else {
3036 			r = svm_migrate_vram_to_ram(prange, mm,
3037 					KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU,
3038 					NULL);
3039 		}
3040 		if (r) {
3041 			pr_debug("failed %d to migrate svms %p [0x%lx 0x%lx]\n",
3042 				 r, svms, prange->start, prange->last);
3043 			goto out_unlock_range;
3044 		}
3045 	}
3046 
3047 	r = svm_range_validate_and_map(mm, prange, gpuidx, false, false, false);
3048 	if (r)
3049 		pr_debug("failed %d to map svms 0x%p [0x%lx 0x%lx] to gpus\n",
3050 			 r, svms, prange->start, prange->last);
3051 
3052 	kfd_smi_event_page_fault_end(node, p->lead_thread->pid, addr,
3053 				     migration);
3054 
3055 out_unlock_range:
3056 	mutex_unlock(&prange->migrate_mutex);
3057 out_unlock_svms:
3058 	mutex_unlock(&svms->lock);
3059 	mmap_read_unlock(mm);
3060 
3061 	svm_range_count_fault(node, p, gpuidx);
3062 
3063 	mmput(mm);
3064 out:
3065 	kfd_unref_process(p);
3066 
3067 	if (r == -EAGAIN) {
3068 		pr_debug("recover vm fault later\n");
3069 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
3070 		r = 0;
3071 	}
3072 	return r;
3073 }
3074 
3075 int
3076 svm_range_switch_xnack_reserve_mem(struct kfd_process *p, bool xnack_enabled)
3077 {
3078 	struct svm_range *prange, *pchild;
3079 	uint64_t reserved_size = 0;
3080 	uint64_t size;
3081 	int r = 0;
3082 
3083 	pr_debug("switching xnack from %d to %d\n", p->xnack_enabled, xnack_enabled);
3084 
3085 	mutex_lock(&p->svms.lock);
3086 
3087 	list_for_each_entry(prange, &p->svms.list, list) {
3088 		svm_range_lock(prange);
3089 		list_for_each_entry(pchild, &prange->child_list, child_list) {
3090 			size = (pchild->last - pchild->start + 1) << PAGE_SHIFT;
3091 			if (xnack_enabled) {
3092 				amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3093 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3094 			} else {
3095 				r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3096 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3097 				if (r)
3098 					goto out_unlock;
3099 				reserved_size += size;
3100 			}
3101 		}
3102 
3103 		size = (prange->last - prange->start + 1) << PAGE_SHIFT;
3104 		if (xnack_enabled) {
3105 			amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3106 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3107 		} else {
3108 			r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3109 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3110 			if (r)
3111 				goto out_unlock;
3112 			reserved_size += size;
3113 		}
3114 out_unlock:
3115 		svm_range_unlock(prange);
3116 		if (r)
3117 			break;
3118 	}
3119 
3120 	if (r)
3121 		amdgpu_amdkfd_unreserve_mem_limit(NULL, reserved_size,
3122 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3123 	else
3124 		/* Change xnack mode must be inside svms lock, to avoid race with
3125 		 * svm_range_deferred_list_work unreserve memory in parallel.
3126 		 */
3127 		p->xnack_enabled = xnack_enabled;
3128 
3129 	mutex_unlock(&p->svms.lock);
3130 	return r;
3131 }
3132 
3133 void svm_range_list_fini(struct kfd_process *p)
3134 {
3135 	struct svm_range *prange;
3136 	struct svm_range *next;
3137 
3138 	pr_debug("pasid 0x%x svms 0x%p\n", p->pasid, &p->svms);
3139 
3140 	cancel_delayed_work_sync(&p->svms.restore_work);
3141 
3142 	/* Ensure list work is finished before process is destroyed */
3143 	flush_work(&p->svms.deferred_list_work);
3144 
3145 	/*
3146 	 * Ensure no retry fault comes in afterwards, as page fault handler will
3147 	 * not find kfd process and take mm lock to recover fault.
3148 	 */
3149 	atomic_inc(&p->svms.drain_pagefaults);
3150 	svm_range_drain_retry_fault(&p->svms);
3151 
3152 	list_for_each_entry_safe(prange, next, &p->svms.list, list) {
3153 		svm_range_unlink(prange);
3154 		svm_range_remove_notifier(prange);
3155 		svm_range_free(prange, true);
3156 	}
3157 
3158 	mutex_destroy(&p->svms.lock);
3159 
3160 	pr_debug("pasid 0x%x svms 0x%p done\n", p->pasid, &p->svms);
3161 }
3162 
3163 int svm_range_list_init(struct kfd_process *p)
3164 {
3165 	struct svm_range_list *svms = &p->svms;
3166 	int i;
3167 
3168 	svms->objects = RB_ROOT_CACHED;
3169 	mutex_init(&svms->lock);
3170 	INIT_LIST_HEAD(&svms->list);
3171 	atomic_set(&svms->evicted_ranges, 0);
3172 	atomic_set(&svms->drain_pagefaults, 0);
3173 	INIT_DELAYED_WORK(&svms->restore_work, svm_range_restore_work);
3174 	INIT_WORK(&svms->deferred_list_work, svm_range_deferred_list_work);
3175 	INIT_LIST_HEAD(&svms->deferred_range_list);
3176 	INIT_LIST_HEAD(&svms->criu_svm_metadata_list);
3177 	spin_lock_init(&svms->deferred_list_lock);
3178 
3179 	for (i = 0; i < p->n_pdds; i++)
3180 		if (KFD_IS_SVM_API_SUPPORTED(p->pdds[i]->dev->adev))
3181 			bitmap_set(svms->bitmap_supported, i, 1);
3182 
3183 	return 0;
3184 }
3185 
3186 /**
3187  * svm_range_check_vm - check if virtual address range mapped already
3188  * @p: current kfd_process
3189  * @start: range start address, in pages
3190  * @last: range last address, in pages
3191  * @bo_s: mapping start address in pages if address range already mapped
3192  * @bo_l: mapping last address in pages if address range already mapped
3193  *
3194  * The purpose is to avoid virtual address ranges already allocated by
3195  * kfd_ioctl_alloc_memory_of_gpu ioctl.
3196  * It looks for each pdd in the kfd_process.
3197  *
3198  * Context: Process context
3199  *
3200  * Return 0 - OK, if the range is not mapped.
3201  * Otherwise error code:
3202  * -EADDRINUSE - if address is mapped already by kfd_ioctl_alloc_memory_of_gpu
3203  * -ERESTARTSYS - A wait for the buffer to become unreserved was interrupted by
3204  * a signal. Release all buffer reservations and return to user-space.
3205  */
3206 static int
3207 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
3208 		   uint64_t *bo_s, uint64_t *bo_l)
3209 {
3210 	struct amdgpu_bo_va_mapping *mapping;
3211 	struct interval_tree_node *node;
3212 	uint32_t i;
3213 	int r;
3214 
3215 	for (i = 0; i < p->n_pdds; i++) {
3216 		struct amdgpu_vm *vm;
3217 
3218 		if (!p->pdds[i]->drm_priv)
3219 			continue;
3220 
3221 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
3222 		r = amdgpu_bo_reserve(vm->root.bo, false);
3223 		if (r)
3224 			return r;
3225 
3226 		node = interval_tree_iter_first(&vm->va, start, last);
3227 		if (node) {
3228 			pr_debug("range [0x%llx 0x%llx] already TTM mapped\n",
3229 				 start, last);
3230 			mapping = container_of((struct rb_node *)node,
3231 					       struct amdgpu_bo_va_mapping, rb);
3232 			if (bo_s && bo_l) {
3233 				*bo_s = mapping->start;
3234 				*bo_l = mapping->last;
3235 			}
3236 			amdgpu_bo_unreserve(vm->root.bo);
3237 			return -EADDRINUSE;
3238 		}
3239 		amdgpu_bo_unreserve(vm->root.bo);
3240 	}
3241 
3242 	return 0;
3243 }
3244 
3245 /**
3246  * svm_range_is_valid - check if virtual address range is valid
3247  * @p: current kfd_process
3248  * @start: range start address, in pages
3249  * @size: range size, in pages
3250  *
3251  * Valid virtual address range means it belongs to one or more VMAs
3252  *
3253  * Context: Process context
3254  *
3255  * Return:
3256  *  0 - OK, otherwise error code
3257  */
3258 static int
3259 svm_range_is_valid(struct kfd_process *p, uint64_t start, uint64_t size)
3260 {
3261 	const unsigned long device_vma = VM_IO | VM_PFNMAP | VM_MIXEDMAP;
3262 	struct vm_area_struct *vma;
3263 	unsigned long end;
3264 	unsigned long start_unchg = start;
3265 
3266 	start <<= PAGE_SHIFT;
3267 	end = start + (size << PAGE_SHIFT);
3268 	do {
3269 		vma = vma_lookup(p->mm, start);
3270 		if (!vma || (vma->vm_flags & device_vma))
3271 			return -EFAULT;
3272 		start = min(end, vma->vm_end);
3273 	} while (start < end);
3274 
3275 	return svm_range_check_vm(p, start_unchg, (end - 1) >> PAGE_SHIFT, NULL,
3276 				  NULL);
3277 }
3278 
3279 /**
3280  * svm_range_best_prefetch_location - decide the best prefetch location
3281  * @prange: svm range structure
3282  *
3283  * For xnack off:
3284  * If range map to single GPU, the best prefetch location is prefetch_loc, which
3285  * can be CPU or GPU.
3286  *
3287  * If range is ACCESS or ACCESS_IN_PLACE by mGPUs, only if mGPU connection on
3288  * XGMI same hive, the best prefetch location is prefetch_loc GPU, othervise
3289  * the best prefetch location is always CPU, because GPU can not have coherent
3290  * mapping VRAM of other GPUs even with large-BAR PCIe connection.
3291  *
3292  * For xnack on:
3293  * If range is not ACCESS_IN_PLACE by mGPUs, the best prefetch location is
3294  * prefetch_loc, other GPU access will generate vm fault and trigger migration.
3295  *
3296  * If range is ACCESS_IN_PLACE by mGPUs, only if mGPU connection on XGMI same
3297  * hive, the best prefetch location is prefetch_loc GPU, otherwise the best
3298  * prefetch location is always CPU.
3299  *
3300  * Context: Process context
3301  *
3302  * Return:
3303  * 0 for CPU or GPU id
3304  */
3305 static uint32_t
3306 svm_range_best_prefetch_location(struct svm_range *prange)
3307 {
3308 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
3309 	uint32_t best_loc = prange->prefetch_loc;
3310 	struct kfd_process_device *pdd;
3311 	struct kfd_node *bo_node;
3312 	struct kfd_process *p;
3313 	uint32_t gpuidx;
3314 
3315 	p = container_of(prange->svms, struct kfd_process, svms);
3316 
3317 	if (!best_loc || best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED)
3318 		goto out;
3319 
3320 	bo_node = svm_range_get_node_by_id(prange, best_loc);
3321 	if (!bo_node) {
3322 		WARN_ONCE(1, "failed to get valid kfd node at id%x\n", best_loc);
3323 		best_loc = 0;
3324 		goto out;
3325 	}
3326 
3327 	if (bo_node->adev->gmc.is_app_apu) {
3328 		best_loc = 0;
3329 		goto out;
3330 	}
3331 
3332 	if (p->xnack_enabled)
3333 		bitmap_copy(bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
3334 	else
3335 		bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
3336 			  MAX_GPU_INSTANCE);
3337 
3338 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
3339 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
3340 		if (!pdd) {
3341 			pr_debug("failed to get device by idx 0x%x\n", gpuidx);
3342 			continue;
3343 		}
3344 
3345 		if (pdd->dev->adev == bo_node->adev)
3346 			continue;
3347 
3348 		if (!svm_nodes_in_same_hive(pdd->dev, bo_node)) {
3349 			best_loc = 0;
3350 			break;
3351 		}
3352 	}
3353 
3354 out:
3355 	pr_debug("xnack %d svms 0x%p [0x%lx 0x%lx] best loc 0x%x\n",
3356 		 p->xnack_enabled, &p->svms, prange->start, prange->last,
3357 		 best_loc);
3358 
3359 	return best_loc;
3360 }
3361 
3362 /* svm_range_trigger_migration - start page migration if prefetch loc changed
3363  * @mm: current process mm_struct
3364  * @prange: svm range structure
3365  * @migrated: output, true if migration is triggered
3366  *
3367  * If range perfetch_loc is GPU, actual loc is cpu 0, then migrate the range
3368  * from ram to vram.
3369  * If range prefetch_loc is cpu 0, actual loc is GPU, then migrate the range
3370  * from vram to ram.
3371  *
3372  * If GPU vm fault retry is not enabled, migration interact with MMU notifier
3373  * and restore work:
3374  * 1. migrate_vma_setup invalidate pages, MMU notifier callback svm_range_evict
3375  *    stops all queues, schedule restore work
3376  * 2. svm_range_restore_work wait for migration is done by
3377  *    a. svm_range_validate_vram takes prange->migrate_mutex
3378  *    b. svm_range_validate_ram HMM get pages wait for CPU fault handle returns
3379  * 3. restore work update mappings of GPU, resume all queues.
3380  *
3381  * Context: Process context
3382  *
3383  * Return:
3384  * 0 - OK, otherwise - error code of migration
3385  */
3386 static int
3387 svm_range_trigger_migration(struct mm_struct *mm, struct svm_range *prange,
3388 			    bool *migrated)
3389 {
3390 	uint32_t best_loc;
3391 	int r = 0;
3392 
3393 	*migrated = false;
3394 	best_loc = svm_range_best_prefetch_location(prange);
3395 
3396 	if (best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3397 	    best_loc == prange->actual_loc)
3398 		return 0;
3399 
3400 	if (!best_loc) {
3401 		r = svm_migrate_vram_to_ram(prange, mm,
3402 					KFD_MIGRATE_TRIGGER_PREFETCH, NULL);
3403 		*migrated = !r;
3404 		return r;
3405 	}
3406 
3407 	r = svm_migrate_to_vram(prange, best_loc, mm, KFD_MIGRATE_TRIGGER_PREFETCH);
3408 	*migrated = !r;
3409 
3410 	return r;
3411 }
3412 
3413 int svm_range_schedule_evict_svm_bo(struct amdgpu_amdkfd_fence *fence)
3414 {
3415 	if (!fence)
3416 		return -EINVAL;
3417 
3418 	if (dma_fence_is_signaled(&fence->base))
3419 		return 0;
3420 
3421 	if (fence->svm_bo) {
3422 		WRITE_ONCE(fence->svm_bo->evicting, 1);
3423 		schedule_work(&fence->svm_bo->eviction_work);
3424 	}
3425 
3426 	return 0;
3427 }
3428 
3429 static void svm_range_evict_svm_bo_worker(struct work_struct *work)
3430 {
3431 	struct svm_range_bo *svm_bo;
3432 	struct mm_struct *mm;
3433 	int r = 0;
3434 
3435 	svm_bo = container_of(work, struct svm_range_bo, eviction_work);
3436 	if (!svm_bo_ref_unless_zero(svm_bo))
3437 		return; /* svm_bo was freed while eviction was pending */
3438 
3439 	if (mmget_not_zero(svm_bo->eviction_fence->mm)) {
3440 		mm = svm_bo->eviction_fence->mm;
3441 	} else {
3442 		svm_range_bo_unref(svm_bo);
3443 		return;
3444 	}
3445 
3446 	mmap_read_lock(mm);
3447 	spin_lock(&svm_bo->list_lock);
3448 	while (!list_empty(&svm_bo->range_list) && !r) {
3449 		struct svm_range *prange =
3450 				list_first_entry(&svm_bo->range_list,
3451 						struct svm_range, svm_bo_list);
3452 		int retries = 3;
3453 
3454 		list_del_init(&prange->svm_bo_list);
3455 		spin_unlock(&svm_bo->list_lock);
3456 
3457 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
3458 			 prange->start, prange->last);
3459 
3460 		mutex_lock(&prange->migrate_mutex);
3461 		do {
3462 			r = svm_migrate_vram_to_ram(prange, mm,
3463 					KFD_MIGRATE_TRIGGER_TTM_EVICTION, NULL);
3464 		} while (!r && prange->actual_loc && --retries);
3465 
3466 		if (!r && prange->actual_loc)
3467 			pr_info_once("Migration failed during eviction");
3468 
3469 		if (!prange->actual_loc) {
3470 			mutex_lock(&prange->lock);
3471 			prange->svm_bo = NULL;
3472 			mutex_unlock(&prange->lock);
3473 		}
3474 		mutex_unlock(&prange->migrate_mutex);
3475 
3476 		spin_lock(&svm_bo->list_lock);
3477 	}
3478 	spin_unlock(&svm_bo->list_lock);
3479 	mmap_read_unlock(mm);
3480 	mmput(mm);
3481 
3482 	dma_fence_signal(&svm_bo->eviction_fence->base);
3483 
3484 	/* This is the last reference to svm_bo, after svm_range_vram_node_free
3485 	 * has been called in svm_migrate_vram_to_ram
3486 	 */
3487 	WARN_ONCE(!r && kref_read(&svm_bo->kref) != 1, "This was not the last reference\n");
3488 	svm_range_bo_unref(svm_bo);
3489 }
3490 
3491 static int
3492 svm_range_set_attr(struct kfd_process *p, struct mm_struct *mm,
3493 		   uint64_t start, uint64_t size, uint32_t nattr,
3494 		   struct kfd_ioctl_svm_attribute *attrs)
3495 {
3496 	struct amdkfd_process_info *process_info = p->kgd_process_info;
3497 	struct list_head update_list;
3498 	struct list_head insert_list;
3499 	struct list_head remove_list;
3500 	struct svm_range_list *svms;
3501 	struct svm_range *prange;
3502 	struct svm_range *next;
3503 	bool update_mapping = false;
3504 	bool flush_tlb;
3505 	int r = 0;
3506 
3507 	pr_debug("pasid 0x%x svms 0x%p [0x%llx 0x%llx] pages 0x%llx\n",
3508 		 p->pasid, &p->svms, start, start + size - 1, size);
3509 
3510 	r = svm_range_check_attr(p, nattr, attrs);
3511 	if (r)
3512 		return r;
3513 
3514 	svms = &p->svms;
3515 
3516 	mutex_lock(&process_info->lock);
3517 
3518 	svm_range_list_lock_and_flush_work(svms, mm);
3519 
3520 	r = svm_range_is_valid(p, start, size);
3521 	if (r) {
3522 		pr_debug("invalid range r=%d\n", r);
3523 		mmap_write_unlock(mm);
3524 		goto out;
3525 	}
3526 
3527 	mutex_lock(&svms->lock);
3528 
3529 	/* Add new range and split existing ranges as needed */
3530 	r = svm_range_add(p, start, size, nattr, attrs, &update_list,
3531 			  &insert_list, &remove_list);
3532 	if (r) {
3533 		mutex_unlock(&svms->lock);
3534 		mmap_write_unlock(mm);
3535 		goto out;
3536 	}
3537 	/* Apply changes as a transaction */
3538 	list_for_each_entry_safe(prange, next, &insert_list, list) {
3539 		svm_range_add_to_svms(prange);
3540 		svm_range_add_notifier_locked(mm, prange);
3541 	}
3542 	list_for_each_entry(prange, &update_list, update_list) {
3543 		svm_range_apply_attrs(p, prange, nattr, attrs, &update_mapping);
3544 		/* TODO: unmap ranges from GPU that lost access */
3545 	}
3546 	list_for_each_entry_safe(prange, next, &remove_list, update_list) {
3547 		pr_debug("unlink old 0x%p prange 0x%p [0x%lx 0x%lx]\n",
3548 			 prange->svms, prange, prange->start,
3549 			 prange->last);
3550 		svm_range_unlink(prange);
3551 		svm_range_remove_notifier(prange);
3552 		svm_range_free(prange, false);
3553 	}
3554 
3555 	mmap_write_downgrade(mm);
3556 	/* Trigger migrations and revalidate and map to GPUs as needed. If
3557 	 * this fails we may be left with partially completed actions. There
3558 	 * is no clean way of rolling back to the previous state in such a
3559 	 * case because the rollback wouldn't be guaranteed to work either.
3560 	 */
3561 	list_for_each_entry(prange, &update_list, update_list) {
3562 		bool migrated;
3563 
3564 		mutex_lock(&prange->migrate_mutex);
3565 
3566 		r = svm_range_trigger_migration(mm, prange, &migrated);
3567 		if (r)
3568 			goto out_unlock_range;
3569 
3570 		if (migrated && (!p->xnack_enabled ||
3571 		    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) &&
3572 		    prange->mapped_to_gpu) {
3573 			pr_debug("restore_work will update mappings of GPUs\n");
3574 			mutex_unlock(&prange->migrate_mutex);
3575 			continue;
3576 		}
3577 
3578 		if (!migrated && !update_mapping) {
3579 			mutex_unlock(&prange->migrate_mutex);
3580 			continue;
3581 		}
3582 
3583 		flush_tlb = !migrated && update_mapping && prange->mapped_to_gpu;
3584 
3585 		r = svm_range_validate_and_map(mm, prange, MAX_GPU_INSTANCE,
3586 					       true, true, flush_tlb);
3587 		if (r)
3588 			pr_debug("failed %d to map svm range\n", r);
3589 
3590 out_unlock_range:
3591 		mutex_unlock(&prange->migrate_mutex);
3592 		if (r)
3593 			break;
3594 	}
3595 
3596 	dynamic_svm_range_dump(svms);
3597 
3598 	mutex_unlock(&svms->lock);
3599 	mmap_read_unlock(mm);
3600 out:
3601 	mutex_unlock(&process_info->lock);
3602 
3603 	pr_debug("pasid 0x%x svms 0x%p [0x%llx 0x%llx] done, r=%d\n", p->pasid,
3604 		 &p->svms, start, start + size - 1, r);
3605 
3606 	return r;
3607 }
3608 
3609 static int
3610 svm_range_get_attr(struct kfd_process *p, struct mm_struct *mm,
3611 		   uint64_t start, uint64_t size, uint32_t nattr,
3612 		   struct kfd_ioctl_svm_attribute *attrs)
3613 {
3614 	DECLARE_BITMAP(bitmap_access, MAX_GPU_INSTANCE);
3615 	DECLARE_BITMAP(bitmap_aip, MAX_GPU_INSTANCE);
3616 	bool get_preferred_loc = false;
3617 	bool get_prefetch_loc = false;
3618 	bool get_granularity = false;
3619 	bool get_accessible = false;
3620 	bool get_flags = false;
3621 	uint64_t last = start + size - 1UL;
3622 	uint8_t granularity = 0xff;
3623 	struct interval_tree_node *node;
3624 	struct svm_range_list *svms;
3625 	struct svm_range *prange;
3626 	uint32_t prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3627 	uint32_t location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3628 	uint32_t flags_and = 0xffffffff;
3629 	uint32_t flags_or = 0;
3630 	int gpuidx;
3631 	uint32_t i;
3632 	int r = 0;
3633 
3634 	pr_debug("svms 0x%p [0x%llx 0x%llx] nattr 0x%x\n", &p->svms, start,
3635 		 start + size - 1, nattr);
3636 
3637 	/* Flush pending deferred work to avoid racing with deferred actions from
3638 	 * previous memory map changes (e.g. munmap). Concurrent memory map changes
3639 	 * can still race with get_attr because we don't hold the mmap lock. But that
3640 	 * would be a race condition in the application anyway, and undefined
3641 	 * behaviour is acceptable in that case.
3642 	 */
3643 	flush_work(&p->svms.deferred_list_work);
3644 
3645 	mmap_read_lock(mm);
3646 	r = svm_range_is_valid(p, start, size);
3647 	mmap_read_unlock(mm);
3648 	if (r) {
3649 		pr_debug("invalid range r=%d\n", r);
3650 		return r;
3651 	}
3652 
3653 	for (i = 0; i < nattr; i++) {
3654 		switch (attrs[i].type) {
3655 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3656 			get_preferred_loc = true;
3657 			break;
3658 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3659 			get_prefetch_loc = true;
3660 			break;
3661 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3662 			get_accessible = true;
3663 			break;
3664 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3665 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3666 			get_flags = true;
3667 			break;
3668 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3669 			get_granularity = true;
3670 			break;
3671 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
3672 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
3673 			fallthrough;
3674 		default:
3675 			pr_debug("get invalid attr type 0x%x\n", attrs[i].type);
3676 			return -EINVAL;
3677 		}
3678 	}
3679 
3680 	svms = &p->svms;
3681 
3682 	mutex_lock(&svms->lock);
3683 
3684 	node = interval_tree_iter_first(&svms->objects, start, last);
3685 	if (!node) {
3686 		pr_debug("range attrs not found return default values\n");
3687 		svm_range_set_default_attributes(&location, &prefetch_loc,
3688 						 &granularity, &flags_and);
3689 		flags_or = flags_and;
3690 		if (p->xnack_enabled)
3691 			bitmap_copy(bitmap_access, svms->bitmap_supported,
3692 				    MAX_GPU_INSTANCE);
3693 		else
3694 			bitmap_zero(bitmap_access, MAX_GPU_INSTANCE);
3695 		bitmap_zero(bitmap_aip, MAX_GPU_INSTANCE);
3696 		goto fill_values;
3697 	}
3698 	bitmap_copy(bitmap_access, svms->bitmap_supported, MAX_GPU_INSTANCE);
3699 	bitmap_copy(bitmap_aip, svms->bitmap_supported, MAX_GPU_INSTANCE);
3700 
3701 	while (node) {
3702 		struct interval_tree_node *next;
3703 
3704 		prange = container_of(node, struct svm_range, it_node);
3705 		next = interval_tree_iter_next(node, start, last);
3706 
3707 		if (get_preferred_loc) {
3708 			if (prange->preferred_loc ==
3709 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3710 			    (location != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3711 			     location != prange->preferred_loc)) {
3712 				location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3713 				get_preferred_loc = false;
3714 			} else {
3715 				location = prange->preferred_loc;
3716 			}
3717 		}
3718 		if (get_prefetch_loc) {
3719 			if (prange->prefetch_loc ==
3720 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3721 			    (prefetch_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3722 			     prefetch_loc != prange->prefetch_loc)) {
3723 				prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3724 				get_prefetch_loc = false;
3725 			} else {
3726 				prefetch_loc = prange->prefetch_loc;
3727 			}
3728 		}
3729 		if (get_accessible) {
3730 			bitmap_and(bitmap_access, bitmap_access,
3731 				   prange->bitmap_access, MAX_GPU_INSTANCE);
3732 			bitmap_and(bitmap_aip, bitmap_aip,
3733 				   prange->bitmap_aip, MAX_GPU_INSTANCE);
3734 		}
3735 		if (get_flags) {
3736 			flags_and &= prange->flags;
3737 			flags_or |= prange->flags;
3738 		}
3739 
3740 		if (get_granularity && prange->granularity < granularity)
3741 			granularity = prange->granularity;
3742 
3743 		node = next;
3744 	}
3745 fill_values:
3746 	mutex_unlock(&svms->lock);
3747 
3748 	for (i = 0; i < nattr; i++) {
3749 		switch (attrs[i].type) {
3750 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3751 			attrs[i].value = location;
3752 			break;
3753 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3754 			attrs[i].value = prefetch_loc;
3755 			break;
3756 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3757 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
3758 							       attrs[i].value);
3759 			if (gpuidx < 0) {
3760 				pr_debug("invalid gpuid %x\n", attrs[i].value);
3761 				return -EINVAL;
3762 			}
3763 			if (test_bit(gpuidx, bitmap_access))
3764 				attrs[i].type = KFD_IOCTL_SVM_ATTR_ACCESS;
3765 			else if (test_bit(gpuidx, bitmap_aip))
3766 				attrs[i].type =
3767 					KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE;
3768 			else
3769 				attrs[i].type = KFD_IOCTL_SVM_ATTR_NO_ACCESS;
3770 			break;
3771 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3772 			attrs[i].value = flags_and;
3773 			break;
3774 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3775 			attrs[i].value = ~flags_or;
3776 			break;
3777 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3778 			attrs[i].value = (uint32_t)granularity;
3779 			break;
3780 		}
3781 	}
3782 
3783 	return 0;
3784 }
3785 
3786 int kfd_criu_resume_svm(struct kfd_process *p)
3787 {
3788 	struct kfd_ioctl_svm_attribute *set_attr_new, *set_attr = NULL;
3789 	int nattr_common = 4, nattr_accessibility = 1;
3790 	struct criu_svm_metadata *criu_svm_md = NULL;
3791 	struct svm_range_list *svms = &p->svms;
3792 	struct criu_svm_metadata *next = NULL;
3793 	uint32_t set_flags = 0xffffffff;
3794 	int i, j, num_attrs, ret = 0;
3795 	uint64_t set_attr_size;
3796 	struct mm_struct *mm;
3797 
3798 	if (list_empty(&svms->criu_svm_metadata_list)) {
3799 		pr_debug("No SVM data from CRIU restore stage 2\n");
3800 		return ret;
3801 	}
3802 
3803 	mm = get_task_mm(p->lead_thread);
3804 	if (!mm) {
3805 		pr_err("failed to get mm for the target process\n");
3806 		return -ESRCH;
3807 	}
3808 
3809 	num_attrs = nattr_common + (nattr_accessibility * p->n_pdds);
3810 
3811 	i = j = 0;
3812 	list_for_each_entry(criu_svm_md, &svms->criu_svm_metadata_list, list) {
3813 		pr_debug("criu_svm_md[%d]\n\tstart: 0x%llx size: 0x%llx (npages)\n",
3814 			 i, criu_svm_md->data.start_addr, criu_svm_md->data.size);
3815 
3816 		for (j = 0; j < num_attrs; j++) {
3817 			pr_debug("\ncriu_svm_md[%d]->attrs[%d].type : 0x%x\ncriu_svm_md[%d]->attrs[%d].value : 0x%x\n",
3818 				 i, j, criu_svm_md->data.attrs[j].type,
3819 				 i, j, criu_svm_md->data.attrs[j].value);
3820 			switch (criu_svm_md->data.attrs[j].type) {
3821 			/* During Checkpoint operation, the query for
3822 			 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC attribute might
3823 			 * return KFD_IOCTL_SVM_LOCATION_UNDEFINED if they were
3824 			 * not used by the range which was checkpointed. Care
3825 			 * must be taken to not restore with an invalid value
3826 			 * otherwise the gpuidx value will be invalid and
3827 			 * set_attr would eventually fail so just replace those
3828 			 * with another dummy attribute such as
3829 			 * KFD_IOCTL_SVM_ATTR_SET_FLAGS.
3830 			 */
3831 			case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3832 				if (criu_svm_md->data.attrs[j].value ==
3833 				    KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
3834 					criu_svm_md->data.attrs[j].type =
3835 						KFD_IOCTL_SVM_ATTR_SET_FLAGS;
3836 					criu_svm_md->data.attrs[j].value = 0;
3837 				}
3838 				break;
3839 			case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3840 				set_flags = criu_svm_md->data.attrs[j].value;
3841 				break;
3842 			default:
3843 				break;
3844 			}
3845 		}
3846 
3847 		/* CLR_FLAGS is not available via get_attr during checkpoint but
3848 		 * it needs to be inserted before restoring the ranges so
3849 		 * allocate extra space for it before calling set_attr
3850 		 */
3851 		set_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
3852 						(num_attrs + 1);
3853 		set_attr_new = krealloc(set_attr, set_attr_size,
3854 					    GFP_KERNEL);
3855 		if (!set_attr_new) {
3856 			ret = -ENOMEM;
3857 			goto exit;
3858 		}
3859 		set_attr = set_attr_new;
3860 
3861 		memcpy(set_attr, criu_svm_md->data.attrs, num_attrs *
3862 					sizeof(struct kfd_ioctl_svm_attribute));
3863 		set_attr[num_attrs].type = KFD_IOCTL_SVM_ATTR_CLR_FLAGS;
3864 		set_attr[num_attrs].value = ~set_flags;
3865 
3866 		ret = svm_range_set_attr(p, mm, criu_svm_md->data.start_addr,
3867 					 criu_svm_md->data.size, num_attrs + 1,
3868 					 set_attr);
3869 		if (ret) {
3870 			pr_err("CRIU: failed to set range attributes\n");
3871 			goto exit;
3872 		}
3873 
3874 		i++;
3875 	}
3876 exit:
3877 	kfree(set_attr);
3878 	list_for_each_entry_safe(criu_svm_md, next, &svms->criu_svm_metadata_list, list) {
3879 		pr_debug("freeing criu_svm_md[]\n\tstart: 0x%llx\n",
3880 						criu_svm_md->data.start_addr);
3881 		kfree(criu_svm_md);
3882 	}
3883 
3884 	mmput(mm);
3885 	return ret;
3886 
3887 }
3888 
3889 int kfd_criu_restore_svm(struct kfd_process *p,
3890 			 uint8_t __user *user_priv_ptr,
3891 			 uint64_t *priv_data_offset,
3892 			 uint64_t max_priv_data_size)
3893 {
3894 	uint64_t svm_priv_data_size, svm_object_md_size, svm_attrs_size;
3895 	int nattr_common = 4, nattr_accessibility = 1;
3896 	struct criu_svm_metadata *criu_svm_md = NULL;
3897 	struct svm_range_list *svms = &p->svms;
3898 	uint32_t num_devices;
3899 	int ret = 0;
3900 
3901 	num_devices = p->n_pdds;
3902 	/* Handle one SVM range object at a time, also the number of gpus are
3903 	 * assumed to be same on the restore node, checking must be done while
3904 	 * evaluating the topology earlier
3905 	 */
3906 
3907 	svm_attrs_size = sizeof(struct kfd_ioctl_svm_attribute) *
3908 		(nattr_common + nattr_accessibility * num_devices);
3909 	svm_object_md_size = sizeof(struct criu_svm_metadata) + svm_attrs_size;
3910 
3911 	svm_priv_data_size = sizeof(struct kfd_criu_svm_range_priv_data) +
3912 								svm_attrs_size;
3913 
3914 	criu_svm_md = kzalloc(svm_object_md_size, GFP_KERNEL);
3915 	if (!criu_svm_md) {
3916 		pr_err("failed to allocate memory to store svm metadata\n");
3917 		return -ENOMEM;
3918 	}
3919 	if (*priv_data_offset + svm_priv_data_size > max_priv_data_size) {
3920 		ret = -EINVAL;
3921 		goto exit;
3922 	}
3923 
3924 	ret = copy_from_user(&criu_svm_md->data, user_priv_ptr + *priv_data_offset,
3925 			     svm_priv_data_size);
3926 	if (ret) {
3927 		ret = -EFAULT;
3928 		goto exit;
3929 	}
3930 	*priv_data_offset += svm_priv_data_size;
3931 
3932 	list_add_tail(&criu_svm_md->list, &svms->criu_svm_metadata_list);
3933 
3934 	return 0;
3935 
3936 
3937 exit:
3938 	kfree(criu_svm_md);
3939 	return ret;
3940 }
3941 
3942 int svm_range_get_info(struct kfd_process *p, uint32_t *num_svm_ranges,
3943 		       uint64_t *svm_priv_data_size)
3944 {
3945 	uint64_t total_size, accessibility_size, common_attr_size;
3946 	int nattr_common = 4, nattr_accessibility = 1;
3947 	int num_devices = p->n_pdds;
3948 	struct svm_range_list *svms;
3949 	struct svm_range *prange;
3950 	uint32_t count = 0;
3951 
3952 	*svm_priv_data_size = 0;
3953 
3954 	svms = &p->svms;
3955 	if (!svms)
3956 		return -EINVAL;
3957 
3958 	mutex_lock(&svms->lock);
3959 	list_for_each_entry(prange, &svms->list, list) {
3960 		pr_debug("prange: 0x%p start: 0x%lx\t npages: 0x%llx\t end: 0x%llx\n",
3961 			 prange, prange->start, prange->npages,
3962 			 prange->start + prange->npages - 1);
3963 		count++;
3964 	}
3965 	mutex_unlock(&svms->lock);
3966 
3967 	*num_svm_ranges = count;
3968 	/* Only the accessbility attributes need to be queried for all the gpus
3969 	 * individually, remaining ones are spanned across the entire process
3970 	 * regardless of the various gpu nodes. Of the remaining attributes,
3971 	 * KFD_IOCTL_SVM_ATTR_CLR_FLAGS need not be saved.
3972 	 *
3973 	 * KFD_IOCTL_SVM_ATTR_PREFERRED_LOC
3974 	 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC
3975 	 * KFD_IOCTL_SVM_ATTR_SET_FLAGS
3976 	 * KFD_IOCTL_SVM_ATTR_GRANULARITY
3977 	 *
3978 	 * ** ACCESSBILITY ATTRIBUTES **
3979 	 * (Considered as one, type is altered during query, value is gpuid)
3980 	 * KFD_IOCTL_SVM_ATTR_ACCESS
3981 	 * KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE
3982 	 * KFD_IOCTL_SVM_ATTR_NO_ACCESS
3983 	 */
3984 	if (*num_svm_ranges > 0) {
3985 		common_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
3986 			nattr_common;
3987 		accessibility_size = sizeof(struct kfd_ioctl_svm_attribute) *
3988 			nattr_accessibility * num_devices;
3989 
3990 		total_size = sizeof(struct kfd_criu_svm_range_priv_data) +
3991 			common_attr_size + accessibility_size;
3992 
3993 		*svm_priv_data_size = *num_svm_ranges * total_size;
3994 	}
3995 
3996 	pr_debug("num_svm_ranges %u total_priv_size %llu\n", *num_svm_ranges,
3997 		 *svm_priv_data_size);
3998 	return 0;
3999 }
4000 
4001 int kfd_criu_checkpoint_svm(struct kfd_process *p,
4002 			    uint8_t __user *user_priv_data,
4003 			    uint64_t *priv_data_offset)
4004 {
4005 	struct kfd_criu_svm_range_priv_data *svm_priv = NULL;
4006 	struct kfd_ioctl_svm_attribute *query_attr = NULL;
4007 	uint64_t svm_priv_data_size, query_attr_size = 0;
4008 	int index, nattr_common = 4, ret = 0;
4009 	struct svm_range_list *svms;
4010 	int num_devices = p->n_pdds;
4011 	struct svm_range *prange;
4012 	struct mm_struct *mm;
4013 
4014 	svms = &p->svms;
4015 	if (!svms)
4016 		return -EINVAL;
4017 
4018 	mm = get_task_mm(p->lead_thread);
4019 	if (!mm) {
4020 		pr_err("failed to get mm for the target process\n");
4021 		return -ESRCH;
4022 	}
4023 
4024 	query_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4025 				(nattr_common + num_devices);
4026 
4027 	query_attr = kzalloc(query_attr_size, GFP_KERNEL);
4028 	if (!query_attr) {
4029 		ret = -ENOMEM;
4030 		goto exit;
4031 	}
4032 
4033 	query_attr[0].type = KFD_IOCTL_SVM_ATTR_PREFERRED_LOC;
4034 	query_attr[1].type = KFD_IOCTL_SVM_ATTR_PREFETCH_LOC;
4035 	query_attr[2].type = KFD_IOCTL_SVM_ATTR_SET_FLAGS;
4036 	query_attr[3].type = KFD_IOCTL_SVM_ATTR_GRANULARITY;
4037 
4038 	for (index = 0; index < num_devices; index++) {
4039 		struct kfd_process_device *pdd = p->pdds[index];
4040 
4041 		query_attr[index + nattr_common].type =
4042 			KFD_IOCTL_SVM_ATTR_ACCESS;
4043 		query_attr[index + nattr_common].value = pdd->user_gpu_id;
4044 	}
4045 
4046 	svm_priv_data_size = sizeof(*svm_priv) + query_attr_size;
4047 
4048 	svm_priv = kzalloc(svm_priv_data_size, GFP_KERNEL);
4049 	if (!svm_priv) {
4050 		ret = -ENOMEM;
4051 		goto exit_query;
4052 	}
4053 
4054 	index = 0;
4055 	list_for_each_entry(prange, &svms->list, list) {
4056 
4057 		svm_priv->object_type = KFD_CRIU_OBJECT_TYPE_SVM_RANGE;
4058 		svm_priv->start_addr = prange->start;
4059 		svm_priv->size = prange->npages;
4060 		memcpy(&svm_priv->attrs, query_attr, query_attr_size);
4061 		pr_debug("CRIU: prange: 0x%p start: 0x%lx\t npages: 0x%llx end: 0x%llx\t size: 0x%llx\n",
4062 			 prange, prange->start, prange->npages,
4063 			 prange->start + prange->npages - 1,
4064 			 prange->npages * PAGE_SIZE);
4065 
4066 		ret = svm_range_get_attr(p, mm, svm_priv->start_addr,
4067 					 svm_priv->size,
4068 					 (nattr_common + num_devices),
4069 					 svm_priv->attrs);
4070 		if (ret) {
4071 			pr_err("CRIU: failed to obtain range attributes\n");
4072 			goto exit_priv;
4073 		}
4074 
4075 		if (copy_to_user(user_priv_data + *priv_data_offset, svm_priv,
4076 				 svm_priv_data_size)) {
4077 			pr_err("Failed to copy svm priv to user\n");
4078 			ret = -EFAULT;
4079 			goto exit_priv;
4080 		}
4081 
4082 		*priv_data_offset += svm_priv_data_size;
4083 
4084 	}
4085 
4086 
4087 exit_priv:
4088 	kfree(svm_priv);
4089 exit_query:
4090 	kfree(query_attr);
4091 exit:
4092 	mmput(mm);
4093 	return ret;
4094 }
4095 
4096 int
4097 svm_ioctl(struct kfd_process *p, enum kfd_ioctl_svm_op op, uint64_t start,
4098 	  uint64_t size, uint32_t nattrs, struct kfd_ioctl_svm_attribute *attrs)
4099 {
4100 	struct mm_struct *mm = current->mm;
4101 	int r;
4102 
4103 	start >>= PAGE_SHIFT;
4104 	size >>= PAGE_SHIFT;
4105 
4106 	switch (op) {
4107 	case KFD_IOCTL_SVM_OP_SET_ATTR:
4108 		r = svm_range_set_attr(p, mm, start, size, nattrs, attrs);
4109 		break;
4110 	case KFD_IOCTL_SVM_OP_GET_ATTR:
4111 		r = svm_range_get_attr(p, mm, start, size, nattrs, attrs);
4112 		break;
4113 	default:
4114 		r = EINVAL;
4115 		break;
4116 	}
4117 
4118 	return r;
4119 }
4120