xref: /linux/drivers/gpu/drm/amd/amdkfd/kfd_svm.c (revision 00e08fb2e7ce88e2ae366cbc79997d71d014b0ac)
1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /*
3  * Copyright 2020-2021 Advanced Micro Devices, Inc.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be included in
13  * all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
19  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
20  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
21  * OTHER DEALINGS IN THE SOFTWARE.
22  */
23 
24 #include <linux/types.h>
25 #include <linux/sched/task.h>
26 #include <linux/dynamic_debug.h>
27 #include <drm/ttm/ttm_tt.h>
28 #include <drm/drm_exec.h>
29 
30 #include "amdgpu_sync.h"
31 #include "amdgpu_object.h"
32 #include "amdgpu_vm.h"
33 #include "amdgpu_hmm.h"
34 #include "amdgpu.h"
35 #include "amdgpu_xgmi.h"
36 #include "amdgpu_reset.h"
37 #include "kfd_priv.h"
38 #include "kfd_svm.h"
39 #include "kfd_migrate.h"
40 #include "kfd_smi_events.h"
41 
42 #ifdef dev_fmt
43 #undef dev_fmt
44 #endif
45 #define dev_fmt(fmt) "kfd_svm: %s: " fmt, __func__
46 
47 #define AMDGPU_SVM_RANGE_RESTORE_DELAY_MS 1
48 
49 /* Long enough to ensure no retry fault comes after svm range is restored and
50  * page table is updated.
51  */
52 #define AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING	(2UL * NSEC_PER_MSEC)
53 #if IS_ENABLED(CONFIG_DYNAMIC_DEBUG)
54 #define dynamic_svm_range_dump(svms) \
55 	_dynamic_func_call_no_desc("svm_range_dump", svm_range_debug_dump, svms)
56 #else
57 #define dynamic_svm_range_dump(svms) \
58 	do { if (0) svm_range_debug_dump(svms); } while (0)
59 #endif
60 
61 /* Giant svm range split into smaller ranges based on this, it is decided using
62  * minimum of all dGPU/APU 1/32 VRAM size, between 2MB to 1GB and alignment to
63  * power of 2MB.
64  */
65 static uint64_t max_svm_range_pages;
66 
67 struct criu_svm_metadata {
68 	struct list_head list;
69 	struct kfd_criu_svm_range_priv_data data;
70 };
71 
72 static void svm_range_evict_svm_bo_worker(struct work_struct *work);
73 static bool
74 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
75 				    const struct mmu_notifier_range *range,
76 				    unsigned long cur_seq);
77 static int
78 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
79 		   uint64_t *bo_s, uint64_t *bo_l);
80 static const struct mmu_interval_notifier_ops svm_range_mn_ops = {
81 	.invalidate = svm_range_cpu_invalidate_pagetables,
82 };
83 
84 /**
85  * svm_range_unlink - unlink svm_range from lists and interval tree
86  * @prange: svm range structure to be removed
87  *
88  * Remove the svm_range from the svms and svm_bo lists and the svms
89  * interval tree.
90  *
91  * Context: The caller must hold svms->lock
92  */
93 static void svm_range_unlink(struct svm_range *prange)
94 {
95 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
96 		 prange, prange->start, prange->last);
97 
98 	if (prange->svm_bo) {
99 		spin_lock(&prange->svm_bo->list_lock);
100 		list_del(&prange->svm_bo_list);
101 		spin_unlock(&prange->svm_bo->list_lock);
102 	}
103 
104 	list_del(&prange->list);
105 	if (prange->it_node.start != 0 && prange->it_node.last != 0)
106 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
107 }
108 
109 static void
110 svm_range_add_notifier_locked(struct mm_struct *mm, struct svm_range *prange)
111 {
112 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
113 		 prange, prange->start, prange->last);
114 
115 	mmu_interval_notifier_insert_locked(&prange->notifier, mm,
116 				     prange->start << PAGE_SHIFT,
117 				     prange->npages << PAGE_SHIFT,
118 				     &svm_range_mn_ops);
119 }
120 
121 /**
122  * svm_range_add_to_svms - add svm range to svms
123  * @prange: svm range structure to be added
124  *
125  * Add the svm range to svms interval tree and link list
126  *
127  * Context: The caller must hold svms->lock
128  */
129 static void svm_range_add_to_svms(struct svm_range *prange)
130 {
131 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
132 		 prange, prange->start, prange->last);
133 
134 	list_move_tail(&prange->list, &prange->svms->list);
135 	prange->it_node.start = prange->start;
136 	prange->it_node.last = prange->last;
137 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
138 }
139 
140 static void svm_range_remove_notifier(struct svm_range *prange)
141 {
142 	pr_debug("remove notifier svms 0x%p prange 0x%p [0x%lx 0x%lx]\n",
143 		 prange->svms, prange,
144 		 prange->notifier.interval_tree.start >> PAGE_SHIFT,
145 		 prange->notifier.interval_tree.last >> PAGE_SHIFT);
146 
147 	if (prange->notifier.interval_tree.start != 0 &&
148 	    prange->notifier.interval_tree.last != 0)
149 		mmu_interval_notifier_remove(&prange->notifier);
150 }
151 
152 static bool
153 svm_is_valid_dma_mapping_addr(struct device *dev, dma_addr_t dma_addr)
154 {
155 	return dma_addr && !dma_mapping_error(dev, dma_addr) &&
156 	       !(dma_addr & SVM_RANGE_VRAM_DOMAIN);
157 }
158 
159 static int
160 svm_range_dma_map_dev(struct amdgpu_device *adev, struct svm_range *prange,
161 		      unsigned long offset, unsigned long npages,
162 		      unsigned long *hmm_pfns, uint32_t gpuidx)
163 {
164 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
165 	dma_addr_t *addr = prange->dma_addr[gpuidx];
166 	struct device *dev = adev->dev;
167 	struct page *page;
168 	int i, r;
169 
170 	if (!addr) {
171 		addr = kvcalloc(prange->npages, sizeof(*addr), GFP_KERNEL);
172 		if (!addr)
173 			return -ENOMEM;
174 		prange->dma_addr[gpuidx] = addr;
175 	}
176 
177 	addr += offset;
178 	for (i = 0; i < npages; i++) {
179 		if (svm_is_valid_dma_mapping_addr(dev, addr[i]))
180 			dma_unmap_page(dev, addr[i], PAGE_SIZE, dir);
181 
182 		page = hmm_pfn_to_page(hmm_pfns[i]);
183 		if (is_zone_device_page(page)) {
184 			struct amdgpu_device *bo_adev = prange->svm_bo->node->adev;
185 
186 			addr[i] = (hmm_pfns[i] << PAGE_SHIFT) +
187 				   bo_adev->vm_manager.vram_base_offset -
188 				   bo_adev->kfd.pgmap.range.start;
189 			addr[i] |= SVM_RANGE_VRAM_DOMAIN;
190 			pr_debug_ratelimited("vram address: 0x%llx\n", addr[i]);
191 			continue;
192 		}
193 		addr[i] = dma_map_page(dev, page, 0, PAGE_SIZE, dir);
194 		r = dma_mapping_error(dev, addr[i]);
195 		if (r) {
196 			dev_err(dev, "failed %d dma_map_page\n", r);
197 			return r;
198 		}
199 		pr_debug_ratelimited("dma mapping 0x%llx for page addr 0x%lx\n",
200 				     addr[i] >> PAGE_SHIFT, page_to_pfn(page));
201 	}
202 
203 	return 0;
204 }
205 
206 static int
207 svm_range_dma_map(struct svm_range *prange, unsigned long *bitmap,
208 		  unsigned long offset, unsigned long npages,
209 		  unsigned long *hmm_pfns)
210 {
211 	struct kfd_process *p;
212 	uint32_t gpuidx;
213 	int r;
214 
215 	p = container_of(prange->svms, struct kfd_process, svms);
216 
217 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
218 		struct kfd_process_device *pdd;
219 
220 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
221 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
222 		if (!pdd) {
223 			pr_debug("failed to find device idx %d\n", gpuidx);
224 			return -EINVAL;
225 		}
226 
227 		r = svm_range_dma_map_dev(pdd->dev->adev, prange, offset, npages,
228 					  hmm_pfns, gpuidx);
229 		if (r)
230 			break;
231 	}
232 
233 	return r;
234 }
235 
236 void svm_range_dma_unmap_dev(struct device *dev, dma_addr_t *dma_addr,
237 			 unsigned long offset, unsigned long npages)
238 {
239 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
240 	int i;
241 
242 	if (!dma_addr)
243 		return;
244 
245 	for (i = offset; i < offset + npages; i++) {
246 		if (!svm_is_valid_dma_mapping_addr(dev, dma_addr[i]))
247 			continue;
248 		pr_debug_ratelimited("unmap 0x%llx\n", dma_addr[i] >> PAGE_SHIFT);
249 		dma_unmap_page(dev, dma_addr[i], PAGE_SIZE, dir);
250 		dma_addr[i] = 0;
251 	}
252 }
253 
254 void svm_range_dma_unmap(struct svm_range *prange)
255 {
256 	struct kfd_process_device *pdd;
257 	dma_addr_t *dma_addr;
258 	struct device *dev;
259 	struct kfd_process *p;
260 	uint32_t gpuidx;
261 
262 	p = container_of(prange->svms, struct kfd_process, svms);
263 
264 	for (gpuidx = 0; gpuidx < MAX_GPU_INSTANCE; gpuidx++) {
265 		dma_addr = prange->dma_addr[gpuidx];
266 		if (!dma_addr)
267 			continue;
268 
269 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
270 		if (!pdd) {
271 			pr_debug("failed to find device idx %d\n", gpuidx);
272 			continue;
273 		}
274 		dev = &pdd->dev->adev->pdev->dev;
275 
276 		svm_range_dma_unmap_dev(dev, dma_addr, 0, prange->npages);
277 	}
278 }
279 
280 static void svm_range_free(struct svm_range *prange, bool do_unmap)
281 {
282 	uint64_t size = (prange->last - prange->start + 1) << PAGE_SHIFT;
283 	struct kfd_process *p = container_of(prange->svms, struct kfd_process, svms);
284 	uint32_t gpuidx;
285 
286 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms, prange,
287 		 prange->start, prange->last);
288 
289 	svm_range_vram_node_free(prange);
290 	if (do_unmap)
291 		svm_range_dma_unmap(prange);
292 
293 	if (do_unmap && !p->xnack_enabled) {
294 		pr_debug("unreserve prange 0x%p size: 0x%llx\n", prange, size);
295 		amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
296 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
297 	}
298 
299 	/* free dma_addr array for each gpu */
300 	for (gpuidx = 0; gpuidx < MAX_GPU_INSTANCE; gpuidx++) {
301 		if (prange->dma_addr[gpuidx]) {
302 			kvfree(prange->dma_addr[gpuidx]);
303 			prange->dma_addr[gpuidx] = NULL;
304 		}
305 	}
306 
307 	mutex_destroy(&prange->lock);
308 	mutex_destroy(&prange->migrate_mutex);
309 	kfree(prange);
310 }
311 
312 static void
313 svm_range_set_default_attributes(struct svm_range_list *svms, int32_t *location,
314 				 int32_t *prefetch_loc, uint8_t *granularity,
315 				 uint32_t *flags)
316 {
317 	*location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
318 	*prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
319 	*granularity = svms->default_granularity;
320 	*flags =
321 		KFD_IOCTL_SVM_FLAG_HOST_ACCESS | KFD_IOCTL_SVM_FLAG_COHERENT;
322 }
323 
324 static struct
325 svm_range *svm_range_new(struct svm_range_list *svms, uint64_t start,
326 			 uint64_t last, bool update_mem_usage)
327 {
328 	uint64_t size = last - start + 1;
329 	struct svm_range *prange;
330 	struct kfd_process *p;
331 
332 	prange = kzalloc(sizeof(*prange), GFP_KERNEL);
333 	if (!prange)
334 		return NULL;
335 
336 	p = container_of(svms, struct kfd_process, svms);
337 	if (!p->xnack_enabled && update_mem_usage &&
338 	    amdgpu_amdkfd_reserve_mem_limit(NULL, size << PAGE_SHIFT,
339 				    KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0)) {
340 		pr_info("SVM mapping failed, exceeds resident system memory limit\n");
341 		kfree(prange);
342 		return NULL;
343 	}
344 	prange->npages = size;
345 	prange->svms = svms;
346 	prange->start = start;
347 	prange->last = last;
348 	INIT_LIST_HEAD(&prange->list);
349 	INIT_LIST_HEAD(&prange->update_list);
350 	INIT_LIST_HEAD(&prange->svm_bo_list);
351 	INIT_LIST_HEAD(&prange->deferred_list);
352 	INIT_LIST_HEAD(&prange->child_list);
353 	atomic_set(&prange->invalid, 0);
354 	prange->validate_timestamp = 0;
355 	prange->vram_pages = 0;
356 	mutex_init(&prange->migrate_mutex);
357 	mutex_init(&prange->lock);
358 
359 	if (p->xnack_enabled)
360 		bitmap_copy(prange->bitmap_access, svms->bitmap_supported,
361 			    MAX_GPU_INSTANCE);
362 
363 	svm_range_set_default_attributes(svms, &prange->preferred_loc,
364 					 &prange->prefetch_loc,
365 					 &prange->granularity, &prange->flags);
366 
367 	pr_debug("svms 0x%p [0x%llx 0x%llx]\n", svms, start, last);
368 
369 	return prange;
370 }
371 
372 static bool svm_bo_ref_unless_zero(struct svm_range_bo *svm_bo)
373 {
374 	if (!svm_bo || !kref_get_unless_zero(&svm_bo->kref))
375 		return false;
376 
377 	return true;
378 }
379 
380 static void svm_range_bo_release(struct kref *kref)
381 {
382 	struct svm_range_bo *svm_bo;
383 
384 	svm_bo = container_of(kref, struct svm_range_bo, kref);
385 	pr_debug("svm_bo 0x%p\n", svm_bo);
386 
387 	spin_lock(&svm_bo->list_lock);
388 	while (!list_empty(&svm_bo->range_list)) {
389 		struct svm_range *prange =
390 				list_first_entry(&svm_bo->range_list,
391 						struct svm_range, svm_bo_list);
392 		/* list_del_init tells a concurrent svm_range_vram_node_new when
393 		 * it's safe to reuse the svm_bo pointer and svm_bo_list head.
394 		 */
395 		list_del_init(&prange->svm_bo_list);
396 		spin_unlock(&svm_bo->list_lock);
397 
398 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
399 			 prange->start, prange->last);
400 		mutex_lock(&prange->lock);
401 		prange->svm_bo = NULL;
402 		/* prange should not hold vram page now */
403 		WARN_ONCE(prange->actual_loc, "prange should not hold vram page");
404 		mutex_unlock(&prange->lock);
405 
406 		spin_lock(&svm_bo->list_lock);
407 	}
408 	spin_unlock(&svm_bo->list_lock);
409 
410 	if (mmget_not_zero(svm_bo->eviction_fence->mm)) {
411 		struct kfd_process_device *pdd;
412 		struct kfd_process *p;
413 		struct mm_struct *mm;
414 
415 		mm = svm_bo->eviction_fence->mm;
416 		/*
417 		 * The forked child process takes svm_bo device pages ref, svm_bo could be
418 		 * released after parent process is gone.
419 		 */
420 		p = kfd_lookup_process_by_mm(mm);
421 		if (p) {
422 			pdd = kfd_get_process_device_data(svm_bo->node, p);
423 			if (pdd)
424 				atomic64_sub(amdgpu_bo_size(svm_bo->bo), &pdd->vram_usage);
425 			kfd_unref_process(p);
426 		}
427 		mmput(mm);
428 	}
429 
430 	if (!dma_fence_is_signaled(&svm_bo->eviction_fence->base))
431 		/* We're not in the eviction worker. Signal the fence. */
432 		dma_fence_signal(&svm_bo->eviction_fence->base);
433 	dma_fence_put(&svm_bo->eviction_fence->base);
434 	amdgpu_bo_unref(&svm_bo->bo);
435 	kfree(svm_bo);
436 }
437 
438 static void svm_range_bo_wq_release(struct work_struct *work)
439 {
440 	struct svm_range_bo *svm_bo;
441 
442 	svm_bo = container_of(work, struct svm_range_bo, release_work);
443 	svm_range_bo_release(&svm_bo->kref);
444 }
445 
446 static void svm_range_bo_release_async(struct kref *kref)
447 {
448 	struct svm_range_bo *svm_bo;
449 
450 	svm_bo = container_of(kref, struct svm_range_bo, kref);
451 	pr_debug("svm_bo 0x%p\n", svm_bo);
452 	INIT_WORK(&svm_bo->release_work, svm_range_bo_wq_release);
453 	schedule_work(&svm_bo->release_work);
454 }
455 
456 void svm_range_bo_unref_async(struct svm_range_bo *svm_bo)
457 {
458 	kref_put(&svm_bo->kref, svm_range_bo_release_async);
459 }
460 
461 static void svm_range_bo_unref(struct svm_range_bo *svm_bo)
462 {
463 	if (svm_bo)
464 		kref_put(&svm_bo->kref, svm_range_bo_release);
465 }
466 
467 static bool
468 svm_range_validate_svm_bo(struct kfd_node *node, struct svm_range *prange)
469 {
470 	mutex_lock(&prange->lock);
471 	if (!prange->svm_bo) {
472 		mutex_unlock(&prange->lock);
473 		return false;
474 	}
475 	if (prange->ttm_res) {
476 		/* We still have a reference, all is well */
477 		mutex_unlock(&prange->lock);
478 		return true;
479 	}
480 	if (svm_bo_ref_unless_zero(prange->svm_bo)) {
481 		/*
482 		 * Migrate from GPU to GPU, remove range from source svm_bo->node
483 		 * range list, and return false to allocate svm_bo from destination
484 		 * node.
485 		 */
486 		if (prange->svm_bo->node != node) {
487 			mutex_unlock(&prange->lock);
488 
489 			spin_lock(&prange->svm_bo->list_lock);
490 			list_del_init(&prange->svm_bo_list);
491 			spin_unlock(&prange->svm_bo->list_lock);
492 
493 			svm_range_bo_unref(prange->svm_bo);
494 			return false;
495 		}
496 		if (READ_ONCE(prange->svm_bo->evicting)) {
497 			struct dma_fence *f;
498 			struct svm_range_bo *svm_bo;
499 			/* The BO is getting evicted,
500 			 * we need to get a new one
501 			 */
502 			mutex_unlock(&prange->lock);
503 			svm_bo = prange->svm_bo;
504 			f = dma_fence_get(&svm_bo->eviction_fence->base);
505 			svm_range_bo_unref(prange->svm_bo);
506 			/* wait for the fence to avoid long spin-loop
507 			 * at list_empty_careful
508 			 */
509 			dma_fence_wait(f, false);
510 			dma_fence_put(f);
511 		} else {
512 			/* The BO was still around and we got
513 			 * a new reference to it
514 			 */
515 			mutex_unlock(&prange->lock);
516 			pr_debug("reuse old bo svms 0x%p [0x%lx 0x%lx]\n",
517 				 prange->svms, prange->start, prange->last);
518 
519 			prange->ttm_res = prange->svm_bo->bo->tbo.resource;
520 			return true;
521 		}
522 
523 	} else {
524 		mutex_unlock(&prange->lock);
525 	}
526 
527 	/* We need a new svm_bo. Spin-loop to wait for concurrent
528 	 * svm_range_bo_release to finish removing this range from
529 	 * its range list and set prange->svm_bo to null. After this,
530 	 * it is safe to reuse the svm_bo pointer and svm_bo_list head.
531 	 */
532 	while (!list_empty_careful(&prange->svm_bo_list) || prange->svm_bo)
533 		cond_resched();
534 
535 	return false;
536 }
537 
538 static struct svm_range_bo *svm_range_bo_new(void)
539 {
540 	struct svm_range_bo *svm_bo;
541 
542 	svm_bo = kzalloc(sizeof(*svm_bo), GFP_KERNEL);
543 	if (!svm_bo)
544 		return NULL;
545 
546 	kref_init(&svm_bo->kref);
547 	INIT_LIST_HEAD(&svm_bo->range_list);
548 	spin_lock_init(&svm_bo->list_lock);
549 
550 	return svm_bo;
551 }
552 
553 int
554 svm_range_vram_node_new(struct kfd_node *node, struct svm_range *prange,
555 			bool clear)
556 {
557 	struct kfd_process_device *pdd;
558 	struct amdgpu_bo_param bp;
559 	struct svm_range_bo *svm_bo;
560 	struct amdgpu_bo_user *ubo;
561 	struct amdgpu_bo *bo;
562 	struct kfd_process *p;
563 	struct mm_struct *mm;
564 	int r;
565 
566 	p = container_of(prange->svms, struct kfd_process, svms);
567 	pr_debug("process pid: %d svms 0x%p [0x%lx 0x%lx]\n",
568 		 p->lead_thread->pid, prange->svms,
569 		 prange->start, prange->last);
570 
571 	if (svm_range_validate_svm_bo(node, prange))
572 		return 0;
573 
574 	svm_bo = svm_range_bo_new();
575 	if (!svm_bo) {
576 		pr_debug("failed to alloc svm bo\n");
577 		return -ENOMEM;
578 	}
579 	mm = get_task_mm(p->lead_thread);
580 	if (!mm) {
581 		pr_debug("failed to get mm\n");
582 		kfree(svm_bo);
583 		return -ESRCH;
584 	}
585 	svm_bo->node = node;
586 	svm_bo->eviction_fence =
587 		amdgpu_amdkfd_fence_create(dma_fence_context_alloc(1),
588 					   mm,
589 					   svm_bo, p->context_id);
590 	mmput(mm);
591 	INIT_WORK(&svm_bo->eviction_work, svm_range_evict_svm_bo_worker);
592 	svm_bo->evicting = 0;
593 	memset(&bp, 0, sizeof(bp));
594 	bp.size = prange->npages * PAGE_SIZE;
595 	bp.byte_align = PAGE_SIZE;
596 	bp.domain = AMDGPU_GEM_DOMAIN_VRAM;
597 	bp.flags = AMDGPU_GEM_CREATE_NO_CPU_ACCESS;
598 	bp.flags |= clear ? AMDGPU_GEM_CREATE_VRAM_CLEARED : 0;
599 	bp.flags |= AMDGPU_GEM_CREATE_DISCARDABLE;
600 	bp.type = ttm_bo_type_device;
601 	bp.resv = NULL;
602 	if (node->xcp)
603 		bp.xcp_id_plus1 = node->xcp->id + 1;
604 
605 	r = amdgpu_bo_create_user(node->adev, &bp, &ubo);
606 	if (r) {
607 		pr_debug("failed %d to create bo\n", r);
608 		goto create_bo_failed;
609 	}
610 	bo = &ubo->bo;
611 
612 	pr_debug("alloc bo at offset 0x%lx size 0x%lx on partition %d\n",
613 		 bo->tbo.resource->start << PAGE_SHIFT, bp.size,
614 		 bp.xcp_id_plus1 - 1);
615 
616 	r = amdgpu_bo_reserve(bo, true);
617 	if (r) {
618 		pr_debug("failed %d to reserve bo\n", r);
619 		goto reserve_bo_failed;
620 	}
621 
622 	if (clear) {
623 		r = amdgpu_bo_sync_wait(bo, AMDGPU_FENCE_OWNER_KFD, false);
624 		if (r) {
625 			pr_debug("failed %d to sync bo\n", r);
626 			amdgpu_bo_unreserve(bo);
627 			goto reserve_bo_failed;
628 		}
629 	}
630 
631 	r = dma_resv_reserve_fences(bo->tbo.base.resv, 1);
632 	if (r) {
633 		pr_debug("failed %d to reserve bo\n", r);
634 		amdgpu_bo_unreserve(bo);
635 		goto reserve_bo_failed;
636 	}
637 	amdgpu_bo_fence(bo, &svm_bo->eviction_fence->base, true);
638 
639 	amdgpu_bo_unreserve(bo);
640 
641 	svm_bo->bo = bo;
642 	prange->svm_bo = svm_bo;
643 	prange->ttm_res = bo->tbo.resource;
644 	prange->offset = 0;
645 
646 	spin_lock(&svm_bo->list_lock);
647 	list_add(&prange->svm_bo_list, &svm_bo->range_list);
648 	spin_unlock(&svm_bo->list_lock);
649 
650 	pdd = svm_range_get_pdd_by_node(prange, node);
651 	if (pdd)
652 		atomic64_add(amdgpu_bo_size(bo), &pdd->vram_usage);
653 
654 	return 0;
655 
656 reserve_bo_failed:
657 	amdgpu_bo_unref(&bo);
658 create_bo_failed:
659 	dma_fence_put(&svm_bo->eviction_fence->base);
660 	kfree(svm_bo);
661 	prange->ttm_res = NULL;
662 
663 	return r;
664 }
665 
666 void svm_range_vram_node_free(struct svm_range *prange)
667 {
668 	/* serialize prange->svm_bo unref */
669 	mutex_lock(&prange->lock);
670 	/* prange->svm_bo has not been unref */
671 	if (prange->ttm_res) {
672 		prange->ttm_res = NULL;
673 		mutex_unlock(&prange->lock);
674 		svm_range_bo_unref(prange->svm_bo);
675 	} else
676 		mutex_unlock(&prange->lock);
677 }
678 
679 struct kfd_node *
680 svm_range_get_node_by_id(struct svm_range *prange, uint32_t gpu_id)
681 {
682 	struct kfd_process *p;
683 	struct kfd_process_device *pdd;
684 
685 	p = container_of(prange->svms, struct kfd_process, svms);
686 	pdd = kfd_process_device_data_by_id(p, gpu_id);
687 	if (!pdd) {
688 		pr_debug("failed to get kfd process device by id 0x%x\n", gpu_id);
689 		return NULL;
690 	}
691 
692 	return pdd->dev;
693 }
694 
695 struct kfd_process_device *
696 svm_range_get_pdd_by_node(struct svm_range *prange, struct kfd_node *node)
697 {
698 	struct kfd_process *p;
699 
700 	p = container_of(prange->svms, struct kfd_process, svms);
701 
702 	return kfd_get_process_device_data(node, p);
703 }
704 
705 static int svm_range_bo_validate(void *param, struct amdgpu_bo *bo)
706 {
707 	struct ttm_operation_ctx ctx = { false, false };
708 
709 	amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_VRAM);
710 
711 	return ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
712 }
713 
714 static int
715 svm_range_check_attr(struct kfd_process *p,
716 		     uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
717 {
718 	uint32_t i;
719 
720 	for (i = 0; i < nattr; i++) {
721 		uint32_t val = attrs[i].value;
722 		int gpuidx = MAX_GPU_INSTANCE;
723 
724 		switch (attrs[i].type) {
725 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
726 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM &&
727 			    val != KFD_IOCTL_SVM_LOCATION_UNDEFINED)
728 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
729 			break;
730 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
731 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM)
732 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
733 			break;
734 		case KFD_IOCTL_SVM_ATTR_ACCESS:
735 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
736 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
737 			gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
738 			break;
739 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
740 			break;
741 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
742 			break;
743 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
744 			break;
745 		default:
746 			pr_debug("unknown attr type 0x%x\n", attrs[i].type);
747 			return -EINVAL;
748 		}
749 
750 		if (gpuidx < 0) {
751 			pr_debug("no GPU 0x%x found\n", val);
752 			return -EINVAL;
753 		} else if (gpuidx < MAX_GPU_INSTANCE &&
754 			   !test_bit(gpuidx, p->svms.bitmap_supported)) {
755 			pr_debug("GPU 0x%x not supported\n", val);
756 			return -EINVAL;
757 		}
758 	}
759 
760 	return 0;
761 }
762 
763 static void
764 svm_range_apply_attrs(struct kfd_process *p, struct svm_range *prange,
765 		      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
766 		      bool *update_mapping)
767 {
768 	uint32_t i;
769 	int gpuidx;
770 
771 	for (i = 0; i < nattr; i++) {
772 		switch (attrs[i].type) {
773 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
774 			prange->preferred_loc = attrs[i].value;
775 			break;
776 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
777 			prange->prefetch_loc = attrs[i].value;
778 			break;
779 		case KFD_IOCTL_SVM_ATTR_ACCESS:
780 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
781 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
782 			if (!p->xnack_enabled)
783 				*update_mapping = true;
784 
785 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
786 							       attrs[i].value);
787 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
788 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
789 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
790 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
791 				bitmap_set(prange->bitmap_access, gpuidx, 1);
792 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
793 			} else {
794 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
795 				bitmap_set(prange->bitmap_aip, gpuidx, 1);
796 			}
797 			break;
798 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
799 			*update_mapping = true;
800 			prange->flags |= attrs[i].value;
801 			break;
802 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
803 			*update_mapping = true;
804 			prange->flags &= ~attrs[i].value;
805 			break;
806 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
807 			prange->granularity = min_t(uint32_t, attrs[i].value, 0x3F);
808 			break;
809 		default:
810 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
811 		}
812 	}
813 }
814 
815 static bool
816 svm_range_is_same_attrs(struct kfd_process *p, struct svm_range *prange,
817 			uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
818 {
819 	uint32_t i;
820 	int gpuidx;
821 
822 	for (i = 0; i < nattr; i++) {
823 		switch (attrs[i].type) {
824 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
825 			if (prange->preferred_loc != attrs[i].value)
826 				return false;
827 			break;
828 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
829 			/* Prefetch should always trigger a migration even
830 			 * if the value of the attribute didn't change.
831 			 */
832 			return false;
833 		case KFD_IOCTL_SVM_ATTR_ACCESS:
834 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
835 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
836 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
837 							       attrs[i].value);
838 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
839 				if (test_bit(gpuidx, prange->bitmap_access) ||
840 				    test_bit(gpuidx, prange->bitmap_aip))
841 					return false;
842 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
843 				if (!test_bit(gpuidx, prange->bitmap_access))
844 					return false;
845 			} else {
846 				if (!test_bit(gpuidx, prange->bitmap_aip))
847 					return false;
848 			}
849 			break;
850 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
851 			if ((prange->flags & attrs[i].value) != attrs[i].value)
852 				return false;
853 			break;
854 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
855 			if ((prange->flags & attrs[i].value) != 0)
856 				return false;
857 			break;
858 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
859 			if (prange->granularity != attrs[i].value)
860 				return false;
861 			break;
862 		default:
863 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
864 		}
865 	}
866 
867 	return true;
868 }
869 
870 /**
871  * svm_range_debug_dump - print all range information from svms
872  * @svms: svm range list header
873  *
874  * debug output svm range start, end, prefetch location from svms
875  * interval tree and link list
876  *
877  * Context: The caller must hold svms->lock
878  */
879 static void svm_range_debug_dump(struct svm_range_list *svms)
880 {
881 	struct interval_tree_node *node;
882 	struct svm_range *prange;
883 
884 	pr_debug("dump svms 0x%p list\n", svms);
885 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
886 
887 	list_for_each_entry(prange, &svms->list, list) {
888 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
889 			 prange, prange->start, prange->npages,
890 			 prange->start + prange->npages - 1,
891 			 prange->actual_loc);
892 	}
893 
894 	pr_debug("dump svms 0x%p interval tree\n", svms);
895 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
896 	node = interval_tree_iter_first(&svms->objects, 0, ~0ULL);
897 	while (node) {
898 		prange = container_of(node, struct svm_range, it_node);
899 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
900 			 prange, prange->start, prange->npages,
901 			 prange->start + prange->npages - 1,
902 			 prange->actual_loc);
903 		node = interval_tree_iter_next(node, 0, ~0ULL);
904 	}
905 }
906 
907 static void *
908 svm_range_copy_array(void *psrc, size_t size, uint64_t num_elements,
909 		     uint64_t offset, uint64_t *vram_pages)
910 {
911 	unsigned char *src = (unsigned char *)psrc + offset;
912 	unsigned char *dst;
913 	uint64_t i;
914 
915 	dst = kvmalloc_array(num_elements, size, GFP_KERNEL);
916 	if (!dst)
917 		return NULL;
918 
919 	if (!vram_pages) {
920 		memcpy(dst, src, num_elements * size);
921 		return (void *)dst;
922 	}
923 
924 	*vram_pages = 0;
925 	for (i = 0; i < num_elements; i++) {
926 		dma_addr_t *temp;
927 		temp = (dma_addr_t *)dst + i;
928 		*temp = *((dma_addr_t *)src + i);
929 		if (*temp&SVM_RANGE_VRAM_DOMAIN)
930 			(*vram_pages)++;
931 	}
932 
933 	return (void *)dst;
934 }
935 
936 static int
937 svm_range_copy_dma_addrs(struct svm_range *dst, struct svm_range *src)
938 {
939 	int i;
940 
941 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
942 		if (!src->dma_addr[i])
943 			continue;
944 		dst->dma_addr[i] = svm_range_copy_array(src->dma_addr[i],
945 					sizeof(*src->dma_addr[i]), src->npages, 0, NULL);
946 		if (!dst->dma_addr[i])
947 			return -ENOMEM;
948 	}
949 
950 	return 0;
951 }
952 
953 static int
954 svm_range_split_array(void *ppnew, void *ppold, size_t size,
955 		      uint64_t old_start, uint64_t old_n,
956 		      uint64_t new_start, uint64_t new_n, uint64_t *new_vram_pages)
957 {
958 	unsigned char *new, *old, *pold;
959 	uint64_t d;
960 
961 	if (!ppold)
962 		return 0;
963 	pold = *(unsigned char **)ppold;
964 	if (!pold)
965 		return 0;
966 
967 	d = (new_start - old_start) * size;
968 	/* get dma addr array for new range and calculte its vram page number */
969 	new = svm_range_copy_array(pold, size, new_n, d, new_vram_pages);
970 	if (!new)
971 		return -ENOMEM;
972 	d = (new_start == old_start) ? new_n * size : 0;
973 	old = svm_range_copy_array(pold, size, old_n, d, NULL);
974 	if (!old) {
975 		kvfree(new);
976 		return -ENOMEM;
977 	}
978 	kvfree(pold);
979 	*(void **)ppold = old;
980 	*(void **)ppnew = new;
981 
982 	return 0;
983 }
984 
985 static int
986 svm_range_split_pages(struct svm_range *new, struct svm_range *old,
987 		      uint64_t start, uint64_t last)
988 {
989 	uint64_t npages = last - start + 1;
990 	int i, r;
991 
992 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
993 		r = svm_range_split_array(&new->dma_addr[i], &old->dma_addr[i],
994 					  sizeof(*old->dma_addr[i]), old->start,
995 					  npages, new->start, new->npages,
996 					  old->actual_loc ? &new->vram_pages : NULL);
997 		if (r)
998 			return r;
999 	}
1000 	if (old->actual_loc)
1001 		old->vram_pages -= new->vram_pages;
1002 
1003 	return 0;
1004 }
1005 
1006 static int
1007 svm_range_split_nodes(struct svm_range *new, struct svm_range *old,
1008 		      uint64_t start, uint64_t last)
1009 {
1010 	uint64_t npages = last - start + 1;
1011 
1012 	pr_debug("svms 0x%p new prange 0x%p start 0x%lx [0x%llx 0x%llx]\n",
1013 		 new->svms, new, new->start, start, last);
1014 
1015 	if (new->start == old->start) {
1016 		new->offset = old->offset;
1017 		old->offset += new->npages;
1018 	} else {
1019 		new->offset = old->offset + npages;
1020 	}
1021 
1022 	new->svm_bo = svm_range_bo_ref(old->svm_bo);
1023 	new->ttm_res = old->ttm_res;
1024 
1025 	spin_lock(&new->svm_bo->list_lock);
1026 	list_add(&new->svm_bo_list, &new->svm_bo->range_list);
1027 	spin_unlock(&new->svm_bo->list_lock);
1028 
1029 	return 0;
1030 }
1031 
1032 /**
1033  * svm_range_split_adjust - split range and adjust
1034  *
1035  * @new: new range
1036  * @old: the old range
1037  * @start: the old range adjust to start address in pages
1038  * @last: the old range adjust to last address in pages
1039  *
1040  * Copy system memory dma_addr or vram ttm_res in old range to new
1041  * range from new_start up to size new->npages, the remaining old range is from
1042  * start to last
1043  *
1044  * Return:
1045  * 0 - OK, -ENOMEM - out of memory
1046  */
1047 static int
1048 svm_range_split_adjust(struct svm_range *new, struct svm_range *old,
1049 		      uint64_t start, uint64_t last)
1050 {
1051 	int r;
1052 
1053 	pr_debug("svms 0x%p new 0x%lx old [0x%lx 0x%lx] => [0x%llx 0x%llx]\n",
1054 		 new->svms, new->start, old->start, old->last, start, last);
1055 
1056 	if (new->start < old->start ||
1057 	    new->last > old->last) {
1058 		WARN_ONCE(1, "invalid new range start or last\n");
1059 		return -EINVAL;
1060 	}
1061 
1062 	r = svm_range_split_pages(new, old, start, last);
1063 	if (r)
1064 		return r;
1065 
1066 	if (old->actual_loc && old->ttm_res) {
1067 		r = svm_range_split_nodes(new, old, start, last);
1068 		if (r)
1069 			return r;
1070 	}
1071 
1072 	old->npages = last - start + 1;
1073 	old->start = start;
1074 	old->last = last;
1075 	new->flags = old->flags;
1076 	new->preferred_loc = old->preferred_loc;
1077 	new->prefetch_loc = old->prefetch_loc;
1078 	new->actual_loc = old->actual_loc;
1079 	new->granularity = old->granularity;
1080 	new->mapped_to_gpu = old->mapped_to_gpu;
1081 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
1082 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
1083 	atomic_set(&new->queue_refcount, atomic_read(&old->queue_refcount));
1084 
1085 	return 0;
1086 }
1087 
1088 /**
1089  * svm_range_split - split a range in 2 ranges
1090  *
1091  * @prange: the svm range to split
1092  * @start: the remaining range start address in pages
1093  * @last: the remaining range last address in pages
1094  * @new: the result new range generated
1095  *
1096  * Two cases only:
1097  * case 1: if start == prange->start
1098  *         prange ==> prange[start, last]
1099  *         new range [last + 1, prange->last]
1100  *
1101  * case 2: if last == prange->last
1102  *         prange ==> prange[start, last]
1103  *         new range [prange->start, start - 1]
1104  *
1105  * Return:
1106  * 0 - OK, -ENOMEM - out of memory, -EINVAL - invalid start, last
1107  */
1108 static int
1109 svm_range_split(struct svm_range *prange, uint64_t start, uint64_t last,
1110 		struct svm_range **new)
1111 {
1112 	uint64_t old_start = prange->start;
1113 	uint64_t old_last = prange->last;
1114 	struct svm_range_list *svms;
1115 	int r = 0;
1116 
1117 	pr_debug("svms 0x%p [0x%llx 0x%llx] to [0x%llx 0x%llx]\n", prange->svms,
1118 		 old_start, old_last, start, last);
1119 
1120 	if (old_start != start && old_last != last)
1121 		return -EINVAL;
1122 	if (start < old_start || last > old_last)
1123 		return -EINVAL;
1124 
1125 	svms = prange->svms;
1126 	if (old_start == start)
1127 		*new = svm_range_new(svms, last + 1, old_last, false);
1128 	else
1129 		*new = svm_range_new(svms, old_start, start - 1, false);
1130 	if (!*new)
1131 		return -ENOMEM;
1132 
1133 	r = svm_range_split_adjust(*new, prange, start, last);
1134 	if (r) {
1135 		pr_debug("failed %d split [0x%llx 0x%llx] to [0x%llx 0x%llx]\n",
1136 			 r, old_start, old_last, start, last);
1137 		svm_range_free(*new, false);
1138 		*new = NULL;
1139 	}
1140 
1141 	return r;
1142 }
1143 
1144 static int
1145 svm_range_split_tail(struct svm_range *prange, uint64_t new_last,
1146 		     struct list_head *insert_list, struct list_head *remap_list)
1147 {
1148 	unsigned long last_align_down = ALIGN_DOWN(prange->last, 512);
1149 	unsigned long start_align = ALIGN(prange->start, 512);
1150 	bool huge_page_mapping = last_align_down > start_align;
1151 	struct svm_range *tail = NULL;
1152 	int r;
1153 
1154 	r = svm_range_split(prange, prange->start, new_last, &tail);
1155 
1156 	if (r)
1157 		return r;
1158 
1159 	list_add(&tail->list, insert_list);
1160 
1161 	if (huge_page_mapping && tail->start > start_align &&
1162 	    tail->start < last_align_down && (!IS_ALIGNED(tail->start, 512)))
1163 		list_add(&tail->update_list, remap_list);
1164 
1165 	return 0;
1166 }
1167 
1168 static int
1169 svm_range_split_head(struct svm_range *prange, uint64_t new_start,
1170 		     struct list_head *insert_list, struct list_head *remap_list)
1171 {
1172 	unsigned long last_align_down = ALIGN_DOWN(prange->last, 512);
1173 	unsigned long start_align = ALIGN(prange->start, 512);
1174 	bool huge_page_mapping = last_align_down > start_align;
1175 	struct svm_range *head = NULL;
1176 	int r;
1177 
1178 	r = svm_range_split(prange, new_start, prange->last, &head);
1179 
1180 	if (r)
1181 		return r;
1182 
1183 	list_add(&head->list, insert_list);
1184 
1185 	if (huge_page_mapping && head->last + 1 > start_align &&
1186 	    head->last + 1 < last_align_down && (!IS_ALIGNED(head->last, 512)))
1187 		list_add(&head->update_list, remap_list);
1188 
1189 	return 0;
1190 }
1191 
1192 static void
1193 svm_range_add_child(struct svm_range *prange, struct svm_range *pchild, enum svm_work_list_ops op)
1194 {
1195 	pr_debug("add child 0x%p [0x%lx 0x%lx] to prange 0x%p child list %d\n",
1196 		 pchild, pchild->start, pchild->last, prange, op);
1197 
1198 	pchild->work_item.mm = NULL;
1199 	pchild->work_item.op = op;
1200 	list_add_tail(&pchild->child_list, &prange->child_list);
1201 }
1202 
1203 static bool
1204 svm_nodes_in_same_hive(struct kfd_node *node_a, struct kfd_node *node_b)
1205 {
1206 	return (node_a->adev == node_b->adev ||
1207 		amdgpu_xgmi_same_hive(node_a->adev, node_b->adev));
1208 }
1209 
1210 static uint64_t
1211 svm_range_get_pte_flags(struct kfd_node *node, struct amdgpu_vm *vm,
1212 			struct svm_range *prange, int domain)
1213 {
1214 	struct kfd_node *bo_node;
1215 	uint32_t flags = prange->flags;
1216 	uint32_t mapping_flags = 0;
1217 	uint32_t gc_ip_version = KFD_GC_VERSION(node);
1218 	uint64_t pte_flags;
1219 	bool snoop = (domain != SVM_RANGE_VRAM_DOMAIN);
1220 	bool coherent = flags & (KFD_IOCTL_SVM_FLAG_COHERENT | KFD_IOCTL_SVM_FLAG_EXT_COHERENT);
1221 	bool ext_coherent = flags & KFD_IOCTL_SVM_FLAG_EXT_COHERENT;
1222 	unsigned int mtype_local;
1223 
1224 	if (domain == SVM_RANGE_VRAM_DOMAIN)
1225 		bo_node = prange->svm_bo->node;
1226 
1227 	switch (gc_ip_version) {
1228 	case IP_VERSION(9, 4, 1):
1229 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1230 			if (bo_node == node) {
1231 				mapping_flags |= coherent ?
1232 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1233 			} else {
1234 				mapping_flags |= coherent ?
1235 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1236 				if (svm_nodes_in_same_hive(node, bo_node))
1237 					snoop = true;
1238 			}
1239 		} else {
1240 			mapping_flags |= coherent ?
1241 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1242 		}
1243 		break;
1244 	case IP_VERSION(9, 4, 2):
1245 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1246 			if (bo_node == node) {
1247 				mapping_flags |= coherent ?
1248 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1249 				if (node->adev->gmc.xgmi.connected_to_cpu)
1250 					snoop = true;
1251 			} else {
1252 				mapping_flags |= coherent ?
1253 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1254 				if (svm_nodes_in_same_hive(node, bo_node))
1255 					snoop = true;
1256 			}
1257 		} else {
1258 			mapping_flags |= coherent ?
1259 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1260 		}
1261 		break;
1262 	case IP_VERSION(9, 4, 3):
1263 	case IP_VERSION(9, 4, 4):
1264 	case IP_VERSION(9, 5, 0):
1265 		if (ext_coherent)
1266 			mtype_local = AMDGPU_VM_MTYPE_CC;
1267 		else
1268 			mtype_local = amdgpu_mtype_local == 1 ? AMDGPU_VM_MTYPE_NC :
1269 				amdgpu_mtype_local == 2 ? AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1270 		snoop = true;
1271 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1272 			/* local HBM region close to partition */
1273 			if (bo_node->adev == node->adev &&
1274 			    (!bo_node->xcp || !node->xcp || bo_node->xcp->mem_id == node->xcp->mem_id))
1275 				mapping_flags |= mtype_local;
1276 			/* local HBM region far from partition or remote XGMI GPU
1277 			 * with regular system scope coherence
1278 			 */
1279 			else if (svm_nodes_in_same_hive(bo_node, node) && !ext_coherent)
1280 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1281 			/* PCIe P2P on GPUs pre-9.5.0 */
1282 			else if (gc_ip_version < IP_VERSION(9, 5, 0) &&
1283 				 !svm_nodes_in_same_hive(bo_node, node))
1284 				mapping_flags |= AMDGPU_VM_MTYPE_UC;
1285 			/* Other remote memory */
1286 			else
1287 				mapping_flags |= ext_coherent ? AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1288 		/* system memory accessed by the APU */
1289 		} else if (node->adev->flags & AMD_IS_APU) {
1290 			/* On NUMA systems, locality is determined per-page
1291 			 * in amdgpu_gmc_override_vm_pte_flags
1292 			 */
1293 			if (num_possible_nodes() <= 1)
1294 				mapping_flags |= mtype_local;
1295 			else
1296 				mapping_flags |= ext_coherent ? AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1297 		/* system memory accessed by the dGPU */
1298 		} else {
1299 			if (gc_ip_version < IP_VERSION(9, 5, 0) || ext_coherent)
1300 				mapping_flags |= AMDGPU_VM_MTYPE_UC;
1301 			else
1302 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1303 		}
1304 		break;
1305 	case IP_VERSION(12, 0, 0):
1306 	case IP_VERSION(12, 0, 1):
1307 		mapping_flags |= AMDGPU_VM_MTYPE_NC;
1308 		break;
1309 	case IP_VERSION(12, 1, 0):
1310 		snoop = true;
1311 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1312 			/* local HBM  */
1313 			if (bo_node->adev == node->adev)
1314 				mapping_flags |= AMDGPU_VM_MTYPE_RW;
1315 			/* Remote GPU memory */
1316 			else
1317 				mapping_flags |= ext_coherent ? AMDGPU_VM_MTYPE_UC :
1318 								AMDGPU_VM_MTYPE_NC;
1319 		/* system memory accessed by the dGPU */
1320 		} else {
1321 			mapping_flags |= ext_coherent ? AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1322 		}
1323 		break;
1324 	default:
1325 		mapping_flags |= coherent ?
1326 			AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1327 	}
1328 
1329 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_EXEC)
1330 		mapping_flags |= AMDGPU_VM_PAGE_EXECUTABLE;
1331 
1332 	pte_flags = AMDGPU_PTE_VALID;
1333 	pte_flags |= (domain == SVM_RANGE_VRAM_DOMAIN) ? 0 : AMDGPU_PTE_SYSTEM;
1334 	pte_flags |= snoop ? AMDGPU_PTE_SNOOPED : 0;
1335 	if (gc_ip_version >= IP_VERSION(12, 0, 0))
1336 		pte_flags |= AMDGPU_PTE_IS_PTE;
1337 
1338 	amdgpu_gmc_get_vm_pte(node->adev, vm, NULL, mapping_flags, &pte_flags);
1339 	pte_flags |= AMDGPU_PTE_READABLE;
1340 	if (!(flags & KFD_IOCTL_SVM_FLAG_GPU_RO))
1341 		pte_flags |= AMDGPU_PTE_WRITEABLE;
1342 
1343 	if ((gc_ip_version == IP_VERSION(12, 1, 0)) &&
1344 	    node->adev->have_atomics_support)
1345 		pte_flags |= AMDGPU_PTE_BUS_ATOMICS;
1346 
1347 	return pte_flags;
1348 }
1349 
1350 static int
1351 svm_range_unmap_from_gpu(struct amdgpu_device *adev, struct amdgpu_vm *vm,
1352 			 uint64_t start, uint64_t last,
1353 			 struct dma_fence **fence)
1354 {
1355 	uint64_t init_pte_value = adev->gmc.init_pte_flags;
1356 
1357 	pr_debug("[0x%llx 0x%llx]\n", start, last);
1358 
1359 	return amdgpu_vm_update_range(adev, vm, false, true, true, false, NULL, start,
1360 				      last, init_pte_value, 0, 0, NULL, NULL,
1361 				      fence);
1362 }
1363 
1364 static int
1365 svm_range_unmap_from_gpus(struct svm_range *prange, unsigned long start,
1366 			  unsigned long last, uint32_t trigger)
1367 {
1368 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1369 	struct kfd_process_device *pdd;
1370 	struct dma_fence *fence = NULL;
1371 	struct kfd_process *p;
1372 	uint32_t gpuidx;
1373 	int r = 0;
1374 
1375 	if (!prange->mapped_to_gpu) {
1376 		pr_debug("prange 0x%p [0x%lx 0x%lx] not mapped to GPU\n",
1377 			 prange, prange->start, prange->last);
1378 		return 0;
1379 	}
1380 
1381 	if (prange->start == start && prange->last == last) {
1382 		pr_debug("unmap svms 0x%p prange 0x%p\n", prange->svms, prange);
1383 		prange->mapped_to_gpu = false;
1384 	}
1385 
1386 	bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
1387 		  MAX_GPU_INSTANCE);
1388 	p = container_of(prange->svms, struct kfd_process, svms);
1389 
1390 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1391 		pr_debug("unmap from gpu idx 0x%x\n", gpuidx);
1392 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1393 		if (!pdd) {
1394 			pr_debug("failed to find device idx %d\n", gpuidx);
1395 			return -EINVAL;
1396 		}
1397 
1398 		kfd_smi_event_unmap_from_gpu(pdd->dev, p->lead_thread->pid,
1399 					     start, last, trigger);
1400 
1401 		r = svm_range_unmap_from_gpu(pdd->dev->adev,
1402 					     drm_priv_to_vm(pdd->drm_priv),
1403 					     start, last, &fence);
1404 		if (r)
1405 			break;
1406 
1407 		if (fence) {
1408 			r = dma_fence_wait(fence, false);
1409 			dma_fence_put(fence);
1410 			fence = NULL;
1411 			if (r)
1412 				break;
1413 		}
1414 		kfd_flush_tlb(pdd, TLB_FLUSH_HEAVYWEIGHT);
1415 	}
1416 
1417 	return r;
1418 }
1419 
1420 static int
1421 svm_range_map_to_gpu(struct kfd_process_device *pdd, struct svm_range *prange,
1422 		     unsigned long offset, unsigned long npages, bool readonly,
1423 		     dma_addr_t *dma_addr, struct amdgpu_device *bo_adev,
1424 		     struct dma_fence **fence, bool flush_tlb)
1425 {
1426 	struct amdgpu_device *adev = pdd->dev->adev;
1427 	struct amdgpu_vm *vm = drm_priv_to_vm(pdd->drm_priv);
1428 	uint64_t pte_flags;
1429 	unsigned long last_start;
1430 	int last_domain;
1431 	int r = 0;
1432 	int64_t i, j;
1433 
1434 	last_start = prange->start + offset;
1435 
1436 	pr_debug("svms 0x%p [0x%lx 0x%lx] readonly %d\n", prange->svms,
1437 		 last_start, last_start + npages - 1, readonly);
1438 
1439 	for (i = offset; i < offset + npages; i++) {
1440 		last_domain = dma_addr[i] & SVM_RANGE_VRAM_DOMAIN;
1441 		dma_addr[i] &= ~SVM_RANGE_VRAM_DOMAIN;
1442 
1443 		/* Collect all pages in the same address range and memory domain
1444 		 * that can be mapped with a single call to update mapping.
1445 		 */
1446 		if (i < offset + npages - 1 &&
1447 		    last_domain == (dma_addr[i + 1] & SVM_RANGE_VRAM_DOMAIN))
1448 			continue;
1449 
1450 		pr_debug("Mapping range [0x%lx 0x%llx] on domain: %s\n",
1451 			 last_start, prange->start + i, last_domain ? "GPU" : "CPU");
1452 
1453 		pte_flags = svm_range_get_pte_flags(pdd->dev, vm, prange, last_domain);
1454 		if (readonly)
1455 			pte_flags &= ~AMDGPU_PTE_WRITEABLE;
1456 
1457 		pr_debug("svms 0x%p map [0x%lx 0x%llx] vram %d PTE 0x%llx\n",
1458 			 prange->svms, last_start, prange->start + i,
1459 			 (last_domain == SVM_RANGE_VRAM_DOMAIN) ? 1 : 0,
1460 			 pte_flags);
1461 
1462 		/* For dGPU mode, we use same vm_manager to allocate VRAM for
1463 		 * different memory partition based on fpfn/lpfn, we should use
1464 		 * same vm_manager.vram_base_offset regardless memory partition.
1465 		 */
1466 		r = amdgpu_vm_update_range(adev, vm, false, false, flush_tlb, true,
1467 					   NULL, last_start, prange->start + i,
1468 					   pte_flags,
1469 					   (last_start - prange->start) << PAGE_SHIFT,
1470 					   bo_adev ? bo_adev->vm_manager.vram_base_offset : 0,
1471 					   NULL, dma_addr, &vm->last_update);
1472 
1473 		for (j = last_start - prange->start; j <= i; j++)
1474 			dma_addr[j] |= last_domain;
1475 
1476 		if (r) {
1477 			pr_debug("failed %d to map to gpu 0x%lx\n", r, prange->start);
1478 			goto out;
1479 		}
1480 		last_start = prange->start + i + 1;
1481 	}
1482 
1483 	r = amdgpu_vm_update_pdes(adev, vm, false);
1484 	if (r) {
1485 		pr_debug("failed %d to update directories 0x%lx\n", r,
1486 			 prange->start);
1487 		goto out;
1488 	}
1489 
1490 	if (fence)
1491 		*fence = dma_fence_get(vm->last_update);
1492 
1493 out:
1494 	return r;
1495 }
1496 
1497 static int
1498 svm_range_map_to_gpus(struct svm_range *prange, unsigned long offset,
1499 		      unsigned long npages, bool readonly,
1500 		      unsigned long *bitmap, bool wait, bool flush_tlb)
1501 {
1502 	struct kfd_process_device *pdd;
1503 	struct amdgpu_device *bo_adev = NULL;
1504 	struct kfd_process *p;
1505 	struct dma_fence *fence = NULL;
1506 	uint32_t gpuidx;
1507 	int r = 0;
1508 
1509 	if (prange->svm_bo && prange->ttm_res)
1510 		bo_adev = prange->svm_bo->node->adev;
1511 
1512 	p = container_of(prange->svms, struct kfd_process, svms);
1513 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1514 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
1515 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1516 		if (!pdd) {
1517 			pr_debug("failed to find device idx %d\n", gpuidx);
1518 			return -EINVAL;
1519 		}
1520 
1521 		pdd = kfd_bind_process_to_device(pdd->dev, p);
1522 		if (IS_ERR(pdd))
1523 			return -EINVAL;
1524 
1525 		if (bo_adev && pdd->dev->adev != bo_adev &&
1526 		    !amdgpu_xgmi_same_hive(pdd->dev->adev, bo_adev)) {
1527 			pr_debug("cannot map to device idx %d\n", gpuidx);
1528 			continue;
1529 		}
1530 
1531 		r = svm_range_map_to_gpu(pdd, prange, offset, npages, readonly,
1532 					 prange->dma_addr[gpuidx],
1533 					 bo_adev, wait ? &fence : NULL,
1534 					 flush_tlb);
1535 		if (r)
1536 			break;
1537 
1538 		if (fence) {
1539 			r = dma_fence_wait(fence, false);
1540 			dma_fence_put(fence);
1541 			fence = NULL;
1542 			if (r) {
1543 				pr_debug("failed %d to dma fence wait\n", r);
1544 				break;
1545 			}
1546 		}
1547 
1548 		kfd_flush_tlb(pdd, TLB_FLUSH_LEGACY);
1549 	}
1550 
1551 	return r;
1552 }
1553 
1554 struct svm_validate_context {
1555 	struct kfd_process *process;
1556 	struct svm_range *prange;
1557 	bool intr;
1558 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1559 	struct drm_exec exec;
1560 };
1561 
1562 static int svm_range_reserve_bos(struct svm_validate_context *ctx, bool intr)
1563 {
1564 	struct kfd_process_device *pdd;
1565 	struct amdgpu_vm *vm;
1566 	uint32_t gpuidx;
1567 	int r;
1568 
1569 	drm_exec_init(&ctx->exec, intr ? DRM_EXEC_INTERRUPTIBLE_WAIT: 0, 0);
1570 	drm_exec_until_all_locked(&ctx->exec) {
1571 		for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1572 			pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1573 			if (!pdd) {
1574 				pr_debug("failed to find device idx %d\n", gpuidx);
1575 				r = -EINVAL;
1576 				goto unreserve_out;
1577 			}
1578 			vm = drm_priv_to_vm(pdd->drm_priv);
1579 
1580 			r = amdgpu_vm_lock_pd(vm, &ctx->exec, 2);
1581 			drm_exec_retry_on_contention(&ctx->exec);
1582 			if (unlikely(r)) {
1583 				pr_debug("failed %d to reserve bo\n", r);
1584 				goto unreserve_out;
1585 			}
1586 		}
1587 	}
1588 
1589 	for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1590 		pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1591 		if (!pdd) {
1592 			pr_debug("failed to find device idx %d\n", gpuidx);
1593 			r = -EINVAL;
1594 			goto unreserve_out;
1595 		}
1596 
1597 		r = amdgpu_vm_validate(pdd->dev->adev,
1598 				       drm_priv_to_vm(pdd->drm_priv), NULL,
1599 				       svm_range_bo_validate, NULL);
1600 		if (r) {
1601 			pr_debug("failed %d validate pt bos\n", r);
1602 			goto unreserve_out;
1603 		}
1604 	}
1605 
1606 	return 0;
1607 
1608 unreserve_out:
1609 	drm_exec_fini(&ctx->exec);
1610 	return r;
1611 }
1612 
1613 static void svm_range_unreserve_bos(struct svm_validate_context *ctx)
1614 {
1615 	drm_exec_fini(&ctx->exec);
1616 }
1617 
1618 static void *kfd_svm_page_owner(struct kfd_process *p, int32_t gpuidx)
1619 {
1620 	struct kfd_process_device *pdd;
1621 
1622 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1623 	if (!pdd)
1624 		return NULL;
1625 
1626 	return SVM_ADEV_PGMAP_OWNER(pdd->dev->adev);
1627 }
1628 
1629 /*
1630  * Validation+GPU mapping with concurrent invalidation (MMU notifiers)
1631  *
1632  * To prevent concurrent destruction or change of range attributes, the
1633  * svm_read_lock must be held. The caller must not hold the svm_write_lock
1634  * because that would block concurrent evictions and lead to deadlocks. To
1635  * serialize concurrent migrations or validations of the same range, the
1636  * prange->migrate_mutex must be held.
1637  *
1638  * For VRAM ranges, the SVM BO must be allocated and valid (protected by its
1639  * eviction fence.
1640  *
1641  * The following sequence ensures race-free validation and GPU mapping:
1642  *
1643  * 1. Reserve page table (and SVM BO if range is in VRAM)
1644  * 2. hmm_range_fault to get page addresses (if system memory)
1645  * 3. DMA-map pages (if system memory)
1646  * 4-a. Take notifier lock
1647  * 4-b. Check that pages still valid (mmu_interval_read_retry)
1648  * 4-c. Check that the range was not split or otherwise invalidated
1649  * 4-d. Update GPU page table
1650  * 4.e. Release notifier lock
1651  * 5. Release page table (and SVM BO) reservation
1652  */
1653 static int svm_range_validate_and_map(struct mm_struct *mm,
1654 				      unsigned long map_start, unsigned long map_last,
1655 				      struct svm_range *prange, int32_t gpuidx,
1656 				      bool intr, bool wait, bool flush_tlb)
1657 {
1658 	struct svm_validate_context *ctx;
1659 	unsigned long start, end, addr;
1660 	struct kfd_process *p;
1661 	void *owner;
1662 	int32_t idx;
1663 	int r = 0;
1664 
1665 	ctx = kzalloc(sizeof(struct svm_validate_context), GFP_KERNEL);
1666 	if (!ctx)
1667 		return -ENOMEM;
1668 	ctx->process = container_of(prange->svms, struct kfd_process, svms);
1669 	ctx->prange = prange;
1670 	ctx->intr = intr;
1671 
1672 	if (gpuidx < MAX_GPU_INSTANCE) {
1673 		bitmap_zero(ctx->bitmap, MAX_GPU_INSTANCE);
1674 		bitmap_set(ctx->bitmap, gpuidx, 1);
1675 	} else if (ctx->process->xnack_enabled) {
1676 		bitmap_copy(ctx->bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
1677 
1678 		/* If prefetch range to GPU, or GPU retry fault migrate range to
1679 		 * GPU, which has ACCESS attribute to the range, create mapping
1680 		 * on that GPU.
1681 		 */
1682 		if (prange->actual_loc) {
1683 			gpuidx = kfd_process_gpuidx_from_gpuid(ctx->process,
1684 							prange->actual_loc);
1685 			if (gpuidx < 0) {
1686 				WARN_ONCE(1, "failed get device by id 0x%x\n",
1687 					 prange->actual_loc);
1688 				r = -EINVAL;
1689 				goto free_ctx;
1690 			}
1691 			if (test_bit(gpuidx, prange->bitmap_access))
1692 				bitmap_set(ctx->bitmap, gpuidx, 1);
1693 		}
1694 
1695 		/*
1696 		 * If prange is already mapped or with always mapped flag,
1697 		 * update mapping on GPUs with ACCESS attribute
1698 		 */
1699 		if (bitmap_empty(ctx->bitmap, MAX_GPU_INSTANCE)) {
1700 			if (prange->mapped_to_gpu ||
1701 			    prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)
1702 				bitmap_copy(ctx->bitmap, prange->bitmap_access, MAX_GPU_INSTANCE);
1703 		}
1704 	} else {
1705 		bitmap_or(ctx->bitmap, prange->bitmap_access,
1706 			  prange->bitmap_aip, MAX_GPU_INSTANCE);
1707 	}
1708 
1709 	if (bitmap_empty(ctx->bitmap, MAX_GPU_INSTANCE)) {
1710 		r = 0;
1711 		goto free_ctx;
1712 	}
1713 
1714 	if (prange->actual_loc && !prange->ttm_res) {
1715 		/* This should never happen. actual_loc gets set by
1716 		 * svm_migrate_ram_to_vram after allocating a BO.
1717 		 */
1718 		WARN_ONCE(1, "VRAM BO missing during validation\n");
1719 		r = -EINVAL;
1720 		goto free_ctx;
1721 	}
1722 
1723 	r = svm_range_reserve_bos(ctx, intr);
1724 	if (r)
1725 		goto free_ctx;
1726 
1727 	p = container_of(prange->svms, struct kfd_process, svms);
1728 	owner = kfd_svm_page_owner(p, find_first_bit(ctx->bitmap,
1729 						MAX_GPU_INSTANCE));
1730 	for_each_set_bit(idx, ctx->bitmap, MAX_GPU_INSTANCE) {
1731 		if (kfd_svm_page_owner(p, idx) != owner) {
1732 			owner = NULL;
1733 			break;
1734 		}
1735 	}
1736 
1737 	start = map_start << PAGE_SHIFT;
1738 	end = (map_last + 1) << PAGE_SHIFT;
1739 	for (addr = start; !r && addr < end; ) {
1740 		struct amdgpu_hmm_range *range = NULL;
1741 		unsigned long map_start_vma;
1742 		unsigned long map_last_vma;
1743 		struct vm_area_struct *vma;
1744 		unsigned long next = 0;
1745 		unsigned long offset;
1746 		unsigned long npages;
1747 		bool readonly;
1748 
1749 		vma = vma_lookup(mm, addr);
1750 		if (vma) {
1751 			readonly = !(vma->vm_flags & VM_WRITE);
1752 
1753 			next = min(vma->vm_end, end);
1754 			npages = (next - addr) >> PAGE_SHIFT;
1755 			/* HMM requires at least READ permissions. If provided with PROT_NONE,
1756 			 * unmap the memory. If it's not already mapped, this is a no-op
1757 			 * If PROT_WRITE is provided without READ, warn first then unmap
1758 			 */
1759 			if (!(vma->vm_flags & VM_READ)) {
1760 				unsigned long e, s;
1761 
1762 				svm_range_lock(prange);
1763 				if (vma->vm_flags & VM_WRITE)
1764 					pr_debug("VM_WRITE without VM_READ is not supported");
1765 				s = max(start, prange->start);
1766 				e = min(end, prange->last);
1767 				if (e >= s)
1768 					r = svm_range_unmap_from_gpus(prange, s, e,
1769 						       KFD_SVM_UNMAP_TRIGGER_UNMAP_FROM_CPU);
1770 				svm_range_unlock(prange);
1771 				/* If unmap returns non-zero, we'll bail on the next for loop
1772 				 * iteration, so just leave r and continue
1773 				 */
1774 				addr = next;
1775 				continue;
1776 			}
1777 
1778 			WRITE_ONCE(p->svms.faulting_task, current);
1779 			range = amdgpu_hmm_range_alloc(NULL);
1780 			if (likely(range))
1781 				r = amdgpu_hmm_range_get_pages(&prange->notifier, addr, npages,
1782 							       readonly, owner, range);
1783 			else
1784 				r = -ENOMEM;
1785 			WRITE_ONCE(p->svms.faulting_task, NULL);
1786 			if (r)
1787 				pr_debug("failed %d to get svm range pages\n", r);
1788 		} else {
1789 			r = -EFAULT;
1790 		}
1791 
1792 		if (!r) {
1793 			offset = (addr >> PAGE_SHIFT) - prange->start;
1794 			r = svm_range_dma_map(prange, ctx->bitmap, offset, npages,
1795 					      range->hmm_range.hmm_pfns);
1796 			if (r)
1797 				pr_debug("failed %d to dma map range\n", r);
1798 		}
1799 
1800 		svm_range_lock(prange);
1801 
1802 		/* Free backing memory of hmm_range if it was initialized
1803 		 * Override return value to TRY AGAIN only if prior returns
1804 		 * were successful
1805 		 */
1806 		if (range && !amdgpu_hmm_range_valid(range) && !r) {
1807 			pr_debug("hmm update the range, need validate again\n");
1808 			r = -EAGAIN;
1809 		}
1810 
1811 		/* Free the hmm range */
1812 		amdgpu_hmm_range_free(range);
1813 
1814 		if (!r && !list_empty(&prange->child_list)) {
1815 			pr_debug("range split by unmap in parallel, validate again\n");
1816 			r = -EAGAIN;
1817 		}
1818 
1819 		if (!r) {
1820 			map_start_vma = max(map_start, prange->start + offset);
1821 			map_last_vma = min(map_last, prange->start + offset + npages - 1);
1822 			if (map_start_vma <= map_last_vma) {
1823 				offset = map_start_vma - prange->start;
1824 				npages = map_last_vma - map_start_vma + 1;
1825 				r = svm_range_map_to_gpus(prange, offset, npages, readonly,
1826 							  ctx->bitmap, wait, flush_tlb);
1827 			}
1828 		}
1829 
1830 		if (!r && next == end)
1831 			prange->mapped_to_gpu = true;
1832 
1833 		svm_range_unlock(prange);
1834 
1835 		addr = next;
1836 	}
1837 
1838 	svm_range_unreserve_bos(ctx);
1839 	if (!r)
1840 		prange->validate_timestamp = ktime_get_boottime();
1841 
1842 free_ctx:
1843 	kfree(ctx);
1844 
1845 	return r;
1846 }
1847 
1848 /**
1849  * svm_range_list_lock_and_flush_work - flush pending deferred work
1850  *
1851  * @svms: the svm range list
1852  * @mm: the mm structure
1853  *
1854  * Context: Returns with mmap write lock held, pending deferred work flushed
1855  *
1856  */
1857 void
1858 svm_range_list_lock_and_flush_work(struct svm_range_list *svms,
1859 				   struct mm_struct *mm)
1860 {
1861 retry_flush_work:
1862 	flush_work(&svms->deferred_list_work);
1863 	mmap_write_lock(mm);
1864 
1865 	if (list_empty(&svms->deferred_range_list))
1866 		return;
1867 	mmap_write_unlock(mm);
1868 	pr_debug("retry flush\n");
1869 	goto retry_flush_work;
1870 }
1871 
1872 static void svm_range_restore_work(struct work_struct *work)
1873 {
1874 	struct delayed_work *dwork = to_delayed_work(work);
1875 	struct amdkfd_process_info *process_info;
1876 	struct svm_range_list *svms;
1877 	struct svm_range *prange;
1878 	struct kfd_process *p;
1879 	struct mm_struct *mm;
1880 	int evicted_ranges;
1881 	int invalid;
1882 	int r;
1883 
1884 	svms = container_of(dwork, struct svm_range_list, restore_work);
1885 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1886 	if (!evicted_ranges)
1887 		return;
1888 
1889 	pr_debug("restore svm ranges\n");
1890 
1891 	p = container_of(svms, struct kfd_process, svms);
1892 	process_info = p->kgd_process_info;
1893 
1894 	/* Keep mm reference when svm_range_validate_and_map ranges */
1895 	mm = get_task_mm(p->lead_thread);
1896 	if (!mm) {
1897 		pr_debug("svms 0x%p process mm gone\n", svms);
1898 		return;
1899 	}
1900 
1901 	mutex_lock(&process_info->lock);
1902 	svm_range_list_lock_and_flush_work(svms, mm);
1903 	mutex_lock(&svms->lock);
1904 
1905 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1906 
1907 	list_for_each_entry(prange, &svms->list, list) {
1908 		invalid = atomic_read(&prange->invalid);
1909 		if (!invalid)
1910 			continue;
1911 
1912 		pr_debug("restoring svms 0x%p prange 0x%p [0x%lx %lx] inv %d\n",
1913 			 prange->svms, prange, prange->start, prange->last,
1914 			 invalid);
1915 
1916 		/*
1917 		 * If range is migrating, wait for migration is done.
1918 		 */
1919 		mutex_lock(&prange->migrate_mutex);
1920 
1921 		r = svm_range_validate_and_map(mm, prange->start, prange->last, prange,
1922 					       MAX_GPU_INSTANCE, false, true, false);
1923 		if (r)
1924 			pr_debug("failed %d to map 0x%lx to gpus\n", r,
1925 				 prange->start);
1926 
1927 		mutex_unlock(&prange->migrate_mutex);
1928 		if (r)
1929 			goto out_reschedule;
1930 
1931 		if (atomic_cmpxchg(&prange->invalid, invalid, 0) != invalid)
1932 			goto out_reschedule;
1933 	}
1934 
1935 	if (atomic_cmpxchg(&svms->evicted_ranges, evicted_ranges, 0) !=
1936 	    evicted_ranges)
1937 		goto out_reschedule;
1938 
1939 	evicted_ranges = 0;
1940 
1941 	r = kgd2kfd_resume_mm(mm);
1942 	if (r) {
1943 		/* No recovery from this failure. Probably the CP is
1944 		 * hanging. No point trying again.
1945 		 */
1946 		pr_debug("failed %d to resume KFD\n", r);
1947 	}
1948 
1949 	pr_debug("restore svm ranges successfully\n");
1950 
1951 out_reschedule:
1952 	mutex_unlock(&svms->lock);
1953 	mmap_write_unlock(mm);
1954 	mutex_unlock(&process_info->lock);
1955 
1956 	/* If validation failed, reschedule another attempt */
1957 	if (evicted_ranges) {
1958 		pr_debug("reschedule to restore svm range\n");
1959 		queue_delayed_work(system_freezable_wq, &svms->restore_work,
1960 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1961 
1962 		kfd_smi_event_queue_restore_rescheduled(mm);
1963 	}
1964 	mmput(mm);
1965 }
1966 
1967 /**
1968  * svm_range_evict - evict svm range
1969  * @prange: svm range structure
1970  * @mm: current process mm_struct
1971  * @start: starting process queue number
1972  * @last: last process queue number
1973  * @event: mmu notifier event when range is evicted or migrated
1974  *
1975  * Stop all queues of the process to ensure GPU doesn't access the memory, then
1976  * return to let CPU evict the buffer and proceed CPU pagetable update.
1977  *
1978  * Don't need use lock to sync cpu pagetable invalidation with GPU execution.
1979  * If invalidation happens while restore work is running, restore work will
1980  * restart to ensure to get the latest CPU pages mapping to GPU, then start
1981  * the queues.
1982  */
1983 static int
1984 svm_range_evict(struct svm_range *prange, struct mm_struct *mm,
1985 		unsigned long start, unsigned long last,
1986 		enum mmu_notifier_event event)
1987 {
1988 	struct svm_range_list *svms = prange->svms;
1989 	struct svm_range *pchild;
1990 	struct kfd_process *p;
1991 	int r = 0;
1992 
1993 	p = container_of(svms, struct kfd_process, svms);
1994 
1995 	pr_debug("invalidate svms 0x%p prange [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
1996 		 svms, prange->start, prange->last, start, last);
1997 
1998 	if (!p->xnack_enabled ||
1999 	    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) {
2000 		int evicted_ranges;
2001 		bool mapped = prange->mapped_to_gpu;
2002 
2003 		list_for_each_entry(pchild, &prange->child_list, child_list) {
2004 			if (!pchild->mapped_to_gpu)
2005 				continue;
2006 			mapped = true;
2007 			mutex_lock_nested(&pchild->lock, 1);
2008 			if (pchild->start <= last && pchild->last >= start) {
2009 				pr_debug("increment pchild invalid [0x%lx 0x%lx]\n",
2010 					 pchild->start, pchild->last);
2011 				atomic_inc(&pchild->invalid);
2012 			}
2013 			mutex_unlock(&pchild->lock);
2014 		}
2015 
2016 		if (!mapped)
2017 			return r;
2018 
2019 		if (prange->start <= last && prange->last >= start)
2020 			atomic_inc(&prange->invalid);
2021 
2022 		evicted_ranges = atomic_inc_return(&svms->evicted_ranges);
2023 		if (evicted_ranges != 1)
2024 			return r;
2025 
2026 		pr_debug("evicting svms 0x%p range [0x%lx 0x%lx]\n",
2027 			 prange->svms, prange->start, prange->last);
2028 
2029 		/* First eviction, stop the queues */
2030 		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_SVM);
2031 		if (r)
2032 			pr_debug("failed to quiesce KFD\n");
2033 
2034 		pr_debug("schedule to restore svm %p ranges\n", svms);
2035 		queue_delayed_work(system_freezable_wq, &svms->restore_work,
2036 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
2037 	} else {
2038 		unsigned long s, l;
2039 		uint32_t trigger;
2040 
2041 		if (event == MMU_NOTIFY_MIGRATE)
2042 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY_MIGRATE;
2043 		else
2044 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY;
2045 
2046 		pr_debug("invalidate unmap svms 0x%p [0x%lx 0x%lx] from GPUs\n",
2047 			 prange->svms, start, last);
2048 		list_for_each_entry(pchild, &prange->child_list, child_list) {
2049 			mutex_lock_nested(&pchild->lock, 1);
2050 			s = max(start, pchild->start);
2051 			l = min(last, pchild->last);
2052 			if (l >= s)
2053 				svm_range_unmap_from_gpus(pchild, s, l, trigger);
2054 			mutex_unlock(&pchild->lock);
2055 		}
2056 		s = max(start, prange->start);
2057 		l = min(last, prange->last);
2058 		if (l >= s)
2059 			svm_range_unmap_from_gpus(prange, s, l, trigger);
2060 	}
2061 
2062 	return r;
2063 }
2064 
2065 static struct svm_range *svm_range_clone(struct svm_range *old)
2066 {
2067 	struct svm_range *new;
2068 
2069 	new = svm_range_new(old->svms, old->start, old->last, false);
2070 	if (!new)
2071 		return NULL;
2072 	if (svm_range_copy_dma_addrs(new, old)) {
2073 		svm_range_free(new, false);
2074 		return NULL;
2075 	}
2076 	if (old->svm_bo) {
2077 		new->ttm_res = old->ttm_res;
2078 		new->offset = old->offset;
2079 		new->svm_bo = svm_range_bo_ref(old->svm_bo);
2080 		spin_lock(&new->svm_bo->list_lock);
2081 		list_add(&new->svm_bo_list, &new->svm_bo->range_list);
2082 		spin_unlock(&new->svm_bo->list_lock);
2083 	}
2084 	new->flags = old->flags;
2085 	new->preferred_loc = old->preferred_loc;
2086 	new->prefetch_loc = old->prefetch_loc;
2087 	new->actual_loc = old->actual_loc;
2088 	new->granularity = old->granularity;
2089 	new->mapped_to_gpu = old->mapped_to_gpu;
2090 	new->vram_pages = old->vram_pages;
2091 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
2092 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
2093 	atomic_set(&new->queue_refcount, atomic_read(&old->queue_refcount));
2094 
2095 	return new;
2096 }
2097 
2098 void svm_range_set_max_pages(struct amdgpu_device *adev)
2099 {
2100 	uint64_t max_pages;
2101 	uint64_t pages, _pages;
2102 	uint64_t min_pages = 0;
2103 	int i, id;
2104 
2105 	for (i = 0; i < adev->kfd.dev->num_nodes; i++) {
2106 		if (adev->kfd.dev->nodes[i]->xcp)
2107 			id = adev->kfd.dev->nodes[i]->xcp->id;
2108 		else
2109 			id = -1;
2110 		pages = KFD_XCP_MEMORY_SIZE(adev, id) >> 17;
2111 		pages = clamp(pages, 1ULL << 9, 1ULL << 18);
2112 		pages = rounddown_pow_of_two(pages);
2113 		min_pages = min_not_zero(min_pages, pages);
2114 	}
2115 
2116 	do {
2117 		max_pages = READ_ONCE(max_svm_range_pages);
2118 		_pages = min_not_zero(max_pages, min_pages);
2119 	} while (cmpxchg(&max_svm_range_pages, max_pages, _pages) != max_pages);
2120 }
2121 
2122 static int
2123 svm_range_split_new(struct svm_range_list *svms, uint64_t start, uint64_t last,
2124 		    uint64_t max_pages, struct list_head *insert_list,
2125 		    struct list_head *update_list)
2126 {
2127 	struct svm_range *prange;
2128 	uint64_t l;
2129 
2130 	pr_debug("max_svm_range_pages 0x%llx adding [0x%llx 0x%llx]\n",
2131 		 max_pages, start, last);
2132 
2133 	while (last >= start) {
2134 		l = min(last, ALIGN_DOWN(start + max_pages, max_pages) - 1);
2135 
2136 		prange = svm_range_new(svms, start, l, true);
2137 		if (!prange)
2138 			return -ENOMEM;
2139 		list_add(&prange->list, insert_list);
2140 		list_add(&prange->update_list, update_list);
2141 
2142 		start = l + 1;
2143 	}
2144 	return 0;
2145 }
2146 
2147 /**
2148  * svm_range_add - add svm range and handle overlap
2149  * @p: the range add to this process svms
2150  * @start: page size aligned
2151  * @size: page size aligned
2152  * @nattr: number of attributes
2153  * @attrs: array of attributes
2154  * @update_list: output, the ranges need validate and update GPU mapping
2155  * @insert_list: output, the ranges need insert to svms
2156  * @remove_list: output, the ranges are replaced and need remove from svms
2157  * @remap_list: output, remap unaligned svm ranges
2158  *
2159  * Check if the virtual address range has overlap with any existing ranges,
2160  * split partly overlapping ranges and add new ranges in the gaps. All changes
2161  * should be applied to the range_list and interval tree transactionally. If
2162  * any range split or allocation fails, the entire update fails. Therefore any
2163  * existing overlapping svm_ranges are cloned and the original svm_ranges left
2164  * unchanged.
2165  *
2166  * If the transaction succeeds, the caller can update and insert clones and
2167  * new ranges, then free the originals.
2168  *
2169  * Otherwise the caller can free the clones and new ranges, while the old
2170  * svm_ranges remain unchanged.
2171  *
2172  * Context: Process context, caller must hold svms->lock
2173  *
2174  * Return:
2175  * 0 - OK, otherwise error code
2176  */
2177 static int
2178 svm_range_add(struct kfd_process *p, uint64_t start, uint64_t size,
2179 	      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
2180 	      struct list_head *update_list, struct list_head *insert_list,
2181 	      struct list_head *remove_list, struct list_head *remap_list)
2182 {
2183 	unsigned long last = start + size - 1UL;
2184 	struct svm_range_list *svms = &p->svms;
2185 	struct interval_tree_node *node;
2186 	struct svm_range *prange;
2187 	struct svm_range *tmp;
2188 	struct list_head new_list;
2189 	int r = 0;
2190 
2191 	pr_debug("svms 0x%p [0x%llx 0x%lx]\n", &p->svms, start, last);
2192 
2193 	INIT_LIST_HEAD(update_list);
2194 	INIT_LIST_HEAD(insert_list);
2195 	INIT_LIST_HEAD(remove_list);
2196 	INIT_LIST_HEAD(&new_list);
2197 	INIT_LIST_HEAD(remap_list);
2198 
2199 	node = interval_tree_iter_first(&svms->objects, start, last);
2200 	while (node) {
2201 		struct interval_tree_node *next;
2202 		unsigned long next_start;
2203 
2204 		pr_debug("found overlap node [0x%lx 0x%lx]\n", node->start,
2205 			 node->last);
2206 
2207 		prange = container_of(node, struct svm_range, it_node);
2208 		next = interval_tree_iter_next(node, start, last);
2209 		next_start = min(node->last, last) + 1;
2210 
2211 		if (svm_range_is_same_attrs(p, prange, nattr, attrs) &&
2212 		    prange->mapped_to_gpu) {
2213 			/* nothing to do */
2214 		} else if (node->start < start || node->last > last) {
2215 			/* node intersects the update range and its attributes
2216 			 * will change. Clone and split it, apply updates only
2217 			 * to the overlapping part
2218 			 */
2219 			struct svm_range *old = prange;
2220 
2221 			prange = svm_range_clone(old);
2222 			if (!prange) {
2223 				r = -ENOMEM;
2224 				goto out;
2225 			}
2226 
2227 			list_add(&old->update_list, remove_list);
2228 			list_add(&prange->list, insert_list);
2229 			list_add(&prange->update_list, update_list);
2230 
2231 			if (node->start < start) {
2232 				pr_debug("change old range start\n");
2233 				r = svm_range_split_head(prange, start,
2234 							 insert_list, remap_list);
2235 				if (r)
2236 					goto out;
2237 			}
2238 			if (node->last > last) {
2239 				pr_debug("change old range last\n");
2240 				r = svm_range_split_tail(prange, last,
2241 							 insert_list, remap_list);
2242 				if (r)
2243 					goto out;
2244 			}
2245 		} else {
2246 			/* The node is contained within start..last,
2247 			 * just update it
2248 			 */
2249 			list_add(&prange->update_list, update_list);
2250 		}
2251 
2252 		/* insert a new node if needed */
2253 		if (node->start > start) {
2254 			r = svm_range_split_new(svms, start, node->start - 1,
2255 						READ_ONCE(max_svm_range_pages),
2256 						&new_list, update_list);
2257 			if (r)
2258 				goto out;
2259 		}
2260 
2261 		node = next;
2262 		start = next_start;
2263 	}
2264 
2265 	/* add a final range at the end if needed */
2266 	if (start <= last)
2267 		r = svm_range_split_new(svms, start, last,
2268 					READ_ONCE(max_svm_range_pages),
2269 					&new_list, update_list);
2270 
2271 out:
2272 	if (r) {
2273 		list_for_each_entry_safe(prange, tmp, insert_list, list)
2274 			svm_range_free(prange, false);
2275 		list_for_each_entry_safe(prange, tmp, &new_list, list)
2276 			svm_range_free(prange, true);
2277 	} else {
2278 		list_splice(&new_list, insert_list);
2279 	}
2280 
2281 	return r;
2282 }
2283 
2284 static void
2285 svm_range_update_notifier_and_interval_tree(struct mm_struct *mm,
2286 					    struct svm_range *prange)
2287 {
2288 	unsigned long start;
2289 	unsigned long last;
2290 
2291 	start = prange->notifier.interval_tree.start >> PAGE_SHIFT;
2292 	last = prange->notifier.interval_tree.last >> PAGE_SHIFT;
2293 
2294 	if (prange->start == start && prange->last == last)
2295 		return;
2296 
2297 	pr_debug("up notifier 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
2298 		  prange->svms, prange, start, last, prange->start,
2299 		  prange->last);
2300 
2301 	if (start != 0 && last != 0) {
2302 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
2303 		svm_range_remove_notifier(prange);
2304 	}
2305 	prange->it_node.start = prange->start;
2306 	prange->it_node.last = prange->last;
2307 
2308 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
2309 	svm_range_add_notifier_locked(mm, prange);
2310 }
2311 
2312 static void
2313 svm_range_handle_list_op(struct svm_range_list *svms, struct svm_range *prange,
2314 			 struct mm_struct *mm)
2315 {
2316 	switch (prange->work_item.op) {
2317 	case SVM_OP_NULL:
2318 		pr_debug("NULL OP 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2319 			 svms, prange, prange->start, prange->last);
2320 		break;
2321 	case SVM_OP_UNMAP_RANGE:
2322 		pr_debug("remove 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2323 			 svms, prange, prange->start, prange->last);
2324 		svm_range_unlink(prange);
2325 		svm_range_remove_notifier(prange);
2326 		svm_range_free(prange, true);
2327 		break;
2328 	case SVM_OP_UPDATE_RANGE_NOTIFIER:
2329 		pr_debug("update notifier 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2330 			 svms, prange, prange->start, prange->last);
2331 		svm_range_update_notifier_and_interval_tree(mm, prange);
2332 		break;
2333 	case SVM_OP_UPDATE_RANGE_NOTIFIER_AND_MAP:
2334 		pr_debug("update and map 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2335 			 svms, prange, prange->start, prange->last);
2336 		svm_range_update_notifier_and_interval_tree(mm, prange);
2337 		/* TODO: implement deferred validation and mapping */
2338 		break;
2339 	case SVM_OP_ADD_RANGE:
2340 		pr_debug("add 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms, prange,
2341 			 prange->start, prange->last);
2342 		svm_range_add_to_svms(prange);
2343 		svm_range_add_notifier_locked(mm, prange);
2344 		break;
2345 	case SVM_OP_ADD_RANGE_AND_MAP:
2346 		pr_debug("add and map 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms,
2347 			 prange, prange->start, prange->last);
2348 		svm_range_add_to_svms(prange);
2349 		svm_range_add_notifier_locked(mm, prange);
2350 		/* TODO: implement deferred validation and mapping */
2351 		break;
2352 	default:
2353 		WARN_ONCE(1, "Unknown prange 0x%p work op %d\n", prange,
2354 			 prange->work_item.op);
2355 	}
2356 }
2357 
2358 static void svm_range_drain_retry_fault(struct svm_range_list *svms)
2359 {
2360 	struct kfd_process_device *pdd;
2361 	struct kfd_process *p;
2362 	uint32_t i;
2363 
2364 	p = container_of(svms, struct kfd_process, svms);
2365 
2366 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2367 		pdd = p->pdds[i];
2368 		if (!pdd)
2369 			continue;
2370 
2371 		pr_debug("drain retry fault gpu %d svms %p\n", i, svms);
2372 
2373 		if (!down_read_trylock(&pdd->dev->adev->reset_domain->sem))
2374 			continue;
2375 
2376 		amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2377 				pdd->dev->adev->irq.retry_cam_enabled ?
2378 				&pdd->dev->adev->irq.ih :
2379 				&pdd->dev->adev->irq.ih1);
2380 
2381 		if (pdd->dev->adev->irq.retry_cam_enabled)
2382 			amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2383 				&pdd->dev->adev->irq.ih_soft);
2384 
2385 		up_read(&pdd->dev->adev->reset_domain->sem);
2386 
2387 		pr_debug("drain retry fault gpu %d svms 0x%p done\n", i, svms);
2388 	}
2389 }
2390 
2391 static void svm_range_deferred_list_work(struct work_struct *work)
2392 {
2393 	struct svm_range_list *svms;
2394 	struct svm_range *prange;
2395 	struct mm_struct *mm;
2396 
2397 	svms = container_of(work, struct svm_range_list, deferred_list_work);
2398 	pr_debug("enter svms 0x%p\n", svms);
2399 
2400 	spin_lock(&svms->deferred_list_lock);
2401 	while (!list_empty(&svms->deferred_range_list)) {
2402 		prange = list_first_entry(&svms->deferred_range_list,
2403 					  struct svm_range, deferred_list);
2404 		spin_unlock(&svms->deferred_list_lock);
2405 
2406 		pr_debug("prange 0x%p [0x%lx 0x%lx] op %d\n", prange,
2407 			 prange->start, prange->last, prange->work_item.op);
2408 
2409 		mm = prange->work_item.mm;
2410 
2411 		mmap_write_lock(mm);
2412 
2413 		/* Remove from deferred_list must be inside mmap write lock, for
2414 		 * two race cases:
2415 		 * 1. unmap_from_cpu may change work_item.op and add the range
2416 		 *    to deferred_list again, cause use after free bug.
2417 		 * 2. svm_range_list_lock_and_flush_work may hold mmap write
2418 		 *    lock and continue because deferred_list is empty, but
2419 		 *    deferred_list work is actually waiting for mmap lock.
2420 		 */
2421 		spin_lock(&svms->deferred_list_lock);
2422 		list_del_init(&prange->deferred_list);
2423 		spin_unlock(&svms->deferred_list_lock);
2424 
2425 		mutex_lock(&svms->lock);
2426 		mutex_lock(&prange->migrate_mutex);
2427 		while (!list_empty(&prange->child_list)) {
2428 			struct svm_range *pchild;
2429 
2430 			pchild = list_first_entry(&prange->child_list,
2431 						struct svm_range, child_list);
2432 			pr_debug("child prange 0x%p op %d\n", pchild,
2433 				 pchild->work_item.op);
2434 			list_del_init(&pchild->child_list);
2435 			svm_range_handle_list_op(svms, pchild, mm);
2436 		}
2437 		mutex_unlock(&prange->migrate_mutex);
2438 
2439 		svm_range_handle_list_op(svms, prange, mm);
2440 		mutex_unlock(&svms->lock);
2441 		mmap_write_unlock(mm);
2442 
2443 		/* Pairs with mmget in svm_range_add_list_work. If dropping the
2444 		 * last mm refcount, schedule release work to avoid circular locking
2445 		 */
2446 		mmput_async(mm);
2447 
2448 		spin_lock(&svms->deferred_list_lock);
2449 	}
2450 	spin_unlock(&svms->deferred_list_lock);
2451 	pr_debug("exit svms 0x%p\n", svms);
2452 }
2453 
2454 void
2455 svm_range_add_list_work(struct svm_range_list *svms, struct svm_range *prange,
2456 			struct mm_struct *mm, enum svm_work_list_ops op)
2457 {
2458 	spin_lock(&svms->deferred_list_lock);
2459 	/* if prange is on the deferred list */
2460 	if (!list_empty(&prange->deferred_list)) {
2461 		pr_debug("update exist prange 0x%p work op %d\n", prange, op);
2462 		WARN_ONCE(prange->work_item.mm != mm, "unmatch mm\n");
2463 		if (op != SVM_OP_NULL &&
2464 		    prange->work_item.op != SVM_OP_UNMAP_RANGE)
2465 			prange->work_item.op = op;
2466 	} else {
2467 		/* Pairs with mmput in deferred_list_work.
2468 		 * If process is exiting and mm is gone, don't update mmu notifier.
2469 		 */
2470 		if (mmget_not_zero(mm)) {
2471 			prange->work_item.mm = mm;
2472 			prange->work_item.op = op;
2473 			list_add_tail(&prange->deferred_list,
2474 				      &prange->svms->deferred_range_list);
2475 			pr_debug("add prange 0x%p [0x%lx 0x%lx] to work list op %d\n",
2476 				 prange, prange->start, prange->last, op);
2477 		}
2478 	}
2479 	spin_unlock(&svms->deferred_list_lock);
2480 }
2481 
2482 void schedule_deferred_list_work(struct svm_range_list *svms)
2483 {
2484 	spin_lock(&svms->deferred_list_lock);
2485 	if (!list_empty(&svms->deferred_range_list))
2486 		schedule_work(&svms->deferred_list_work);
2487 	spin_unlock(&svms->deferred_list_lock);
2488 }
2489 
2490 static void
2491 svm_range_unmap_split(struct svm_range *parent, struct svm_range *prange, unsigned long start,
2492 		      unsigned long last)
2493 {
2494 	struct svm_range *head;
2495 	struct svm_range *tail;
2496 
2497 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2498 		pr_debug("prange 0x%p [0x%lx 0x%lx] is already freed\n", prange,
2499 			 prange->start, prange->last);
2500 		return;
2501 	}
2502 	if (start > prange->last || last < prange->start)
2503 		return;
2504 
2505 	head = tail = prange;
2506 	if (start > prange->start)
2507 		svm_range_split(prange, prange->start, start - 1, &tail);
2508 	if (last < tail->last)
2509 		svm_range_split(tail, last + 1, tail->last, &head);
2510 
2511 	if (head != prange && tail != prange) {
2512 		svm_range_add_child(parent, head, SVM_OP_UNMAP_RANGE);
2513 		svm_range_add_child(parent, tail, SVM_OP_ADD_RANGE);
2514 	} else if (tail != prange) {
2515 		svm_range_add_child(parent, tail, SVM_OP_UNMAP_RANGE);
2516 	} else if (head != prange) {
2517 		svm_range_add_child(parent, head, SVM_OP_UNMAP_RANGE);
2518 	} else if (parent != prange) {
2519 		prange->work_item.op = SVM_OP_UNMAP_RANGE;
2520 	}
2521 }
2522 
2523 static void
2524 svm_range_unmap_from_cpu(struct mm_struct *mm, struct svm_range *prange,
2525 			 unsigned long start, unsigned long last)
2526 {
2527 	uint32_t trigger = KFD_SVM_UNMAP_TRIGGER_UNMAP_FROM_CPU;
2528 	struct svm_range_list *svms;
2529 	struct svm_range *pchild;
2530 	struct kfd_process *p;
2531 	unsigned long s, l;
2532 	bool unmap_parent;
2533 	uint32_t i;
2534 
2535 	if (atomic_read(&prange->queue_refcount)) {
2536 		int r;
2537 
2538 		pr_warn("Freeing queue vital buffer 0x%lx, queue evicted\n",
2539 			prange->start << PAGE_SHIFT);
2540 		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_SVM);
2541 		if (r)
2542 			pr_debug("failed %d to quiesce KFD queues\n", r);
2543 	}
2544 
2545 	p = kfd_lookup_process_by_mm(mm);
2546 	if (!p)
2547 		return;
2548 	svms = &p->svms;
2549 
2550 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n", svms,
2551 		 prange, prange->start, prange->last, start, last);
2552 
2553 	/* calculate time stamps that are used to decide which page faults need be
2554 	 * dropped or handled before unmap pages from gpu vm
2555 	 */
2556 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2557 		struct kfd_process_device *pdd;
2558 		struct amdgpu_device *adev;
2559 		struct amdgpu_ih_ring *ih;
2560 		uint32_t checkpoint_wptr;
2561 
2562 		pdd = p->pdds[i];
2563 		if (!pdd)
2564 			continue;
2565 
2566 		adev = pdd->dev->adev;
2567 
2568 		/* Check and drain ih1 ring if cam not available */
2569 		if (!adev->irq.retry_cam_enabled && adev->irq.ih1.ring_size) {
2570 			ih = &adev->irq.ih1;
2571 			checkpoint_wptr = amdgpu_ih_get_wptr(adev, ih);
2572 			if (ih->rptr != checkpoint_wptr) {
2573 				svms->checkpoint_ts[i] =
2574 					amdgpu_ih_decode_iv_ts(adev, ih, checkpoint_wptr, -1);
2575 				continue;
2576 			}
2577 		}
2578 
2579 		/* check if dev->irq.ih_soft is not empty */
2580 		ih = &adev->irq.ih_soft;
2581 		checkpoint_wptr = amdgpu_ih_get_wptr(adev, ih);
2582 		if (ih->rptr != checkpoint_wptr)
2583 			svms->checkpoint_ts[i] = amdgpu_ih_decode_iv_ts(adev, ih, checkpoint_wptr, -1);
2584 	}
2585 
2586 	unmap_parent = start <= prange->start && last >= prange->last;
2587 
2588 	list_for_each_entry(pchild, &prange->child_list, child_list) {
2589 		mutex_lock_nested(&pchild->lock, 1);
2590 		s = max(start, pchild->start);
2591 		l = min(last, pchild->last);
2592 		if (l >= s)
2593 			svm_range_unmap_from_gpus(pchild, s, l, trigger);
2594 		svm_range_unmap_split(prange, pchild, start, last);
2595 		mutex_unlock(&pchild->lock);
2596 	}
2597 	s = max(start, prange->start);
2598 	l = min(last, prange->last);
2599 	if (l >= s)
2600 		svm_range_unmap_from_gpus(prange, s, l, trigger);
2601 	svm_range_unmap_split(prange, prange, start, last);
2602 
2603 	if (unmap_parent)
2604 		svm_range_add_list_work(svms, prange, mm, SVM_OP_UNMAP_RANGE);
2605 	else
2606 		svm_range_add_list_work(svms, prange, mm,
2607 					SVM_OP_UPDATE_RANGE_NOTIFIER);
2608 	schedule_deferred_list_work(svms);
2609 
2610 	kfd_unref_process(p);
2611 }
2612 
2613 /**
2614  * svm_range_cpu_invalidate_pagetables - interval notifier callback
2615  * @mni: mmu_interval_notifier struct
2616  * @range: mmu_notifier_range struct
2617  * @cur_seq: value to pass to mmu_interval_set_seq()
2618  *
2619  * If event is MMU_NOTIFY_UNMAP, this is from CPU unmap range, otherwise, it
2620  * is from migration, or CPU page invalidation callback.
2621  *
2622  * For unmap event, unmap range from GPUs, remove prange from svms in a delayed
2623  * work thread, and split prange if only part of prange is unmapped.
2624  *
2625  * For invalidation event, if GPU retry fault is not enabled, evict the queues,
2626  * then schedule svm_range_restore_work to update GPU mapping and resume queues.
2627  * If GPU retry fault is enabled, unmap the svm range from GPU, retry fault will
2628  * update GPU mapping to recover.
2629  *
2630  * Context: mmap lock, notifier_invalidate_start lock are held
2631  *          for invalidate event, prange lock is held if this is from migration
2632  */
2633 static bool
2634 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
2635 				    const struct mmu_notifier_range *range,
2636 				    unsigned long cur_seq)
2637 {
2638 	struct svm_range *prange;
2639 	unsigned long start;
2640 	unsigned long last;
2641 
2642 	if (range->event == MMU_NOTIFY_RELEASE)
2643 		return true;
2644 
2645 	start = mni->interval_tree.start;
2646 	last = mni->interval_tree.last;
2647 	start = max(start, range->start) >> PAGE_SHIFT;
2648 	last = min(last, range->end - 1) >> PAGE_SHIFT;
2649 	pr_debug("[0x%lx 0x%lx] range[0x%lx 0x%lx] notifier[0x%lx 0x%lx] %d\n",
2650 		 start, last, range->start >> PAGE_SHIFT,
2651 		 (range->end - 1) >> PAGE_SHIFT,
2652 		 mni->interval_tree.start >> PAGE_SHIFT,
2653 		 mni->interval_tree.last >> PAGE_SHIFT, range->event);
2654 
2655 	prange = container_of(mni, struct svm_range, notifier);
2656 
2657 	svm_range_lock(prange);
2658 	mmu_interval_set_seq(mni, cur_seq);
2659 
2660 	switch (range->event) {
2661 	case MMU_NOTIFY_UNMAP:
2662 		svm_range_unmap_from_cpu(mni->mm, prange, start, last);
2663 		break;
2664 	default:
2665 		svm_range_evict(prange, mni->mm, start, last, range->event);
2666 		break;
2667 	}
2668 
2669 	svm_range_unlock(prange);
2670 
2671 	return true;
2672 }
2673 
2674 /**
2675  * svm_range_from_addr - find svm range from fault address
2676  * @svms: svm range list header
2677  * @addr: address to search range interval tree, in pages
2678  * @parent: parent range if range is on child list
2679  *
2680  * Context: The caller must hold svms->lock
2681  *
2682  * Return: the svm_range found or NULL
2683  */
2684 struct svm_range *
2685 svm_range_from_addr(struct svm_range_list *svms, unsigned long addr,
2686 		    struct svm_range **parent)
2687 {
2688 	struct interval_tree_node *node;
2689 	struct svm_range *prange;
2690 	struct svm_range *pchild;
2691 
2692 	node = interval_tree_iter_first(&svms->objects, addr, addr);
2693 	if (!node)
2694 		return NULL;
2695 
2696 	prange = container_of(node, struct svm_range, it_node);
2697 	pr_debug("address 0x%lx prange [0x%lx 0x%lx] node [0x%lx 0x%lx]\n",
2698 		 addr, prange->start, prange->last, node->start, node->last);
2699 
2700 	if (addr >= prange->start && addr <= prange->last) {
2701 		if (parent)
2702 			*parent = prange;
2703 		return prange;
2704 	}
2705 	list_for_each_entry(pchild, &prange->child_list, child_list)
2706 		if (addr >= pchild->start && addr <= pchild->last) {
2707 			pr_debug("found address 0x%lx pchild [0x%lx 0x%lx]\n",
2708 				 addr, pchild->start, pchild->last);
2709 			if (parent)
2710 				*parent = prange;
2711 			return pchild;
2712 		}
2713 
2714 	return NULL;
2715 }
2716 
2717 /* svm_range_best_restore_location - decide the best fault restore location
2718  * @prange: svm range structure
2719  * @adev: the GPU on which vm fault happened
2720  *
2721  * This is only called when xnack is on, to decide the best location to restore
2722  * the range mapping after GPU vm fault. Caller uses the best location to do
2723  * migration if actual loc is not best location, then update GPU page table
2724  * mapping to the best location.
2725  *
2726  * If the preferred loc is accessible by faulting GPU, use preferred loc.
2727  * If vm fault gpu idx is on range ACCESSIBLE bitmap, best_loc is vm fault gpu
2728  * If vm fault gpu idx is on range ACCESSIBLE_IN_PLACE bitmap, then
2729  *    if range actual loc is cpu, best_loc is cpu
2730  *    if vm fault gpu is on xgmi same hive of range actual loc gpu, best_loc is
2731  *    range actual loc.
2732  * Otherwise, GPU no access, best_loc is -1.
2733  *
2734  * Return:
2735  * -1 means vm fault GPU no access
2736  * 0 for CPU or GPU id
2737  */
2738 static int32_t
2739 svm_range_best_restore_location(struct svm_range *prange,
2740 				struct kfd_node *node,
2741 				int32_t *gpuidx)
2742 {
2743 	struct kfd_node *bo_node, *preferred_node;
2744 	struct kfd_process *p;
2745 	uint32_t gpuid;
2746 	int r;
2747 
2748 	p = container_of(prange->svms, struct kfd_process, svms);
2749 
2750 	r = kfd_process_gpuid_from_node(p, node, &gpuid, gpuidx);
2751 	if (r < 0) {
2752 		pr_debug("failed to get gpuid from kgd\n");
2753 		return -1;
2754 	}
2755 
2756 	if (node->adev->apu_prefer_gtt)
2757 		return 0;
2758 
2759 	if (prange->preferred_loc == gpuid ||
2760 	    prange->preferred_loc == KFD_IOCTL_SVM_LOCATION_SYSMEM) {
2761 		return prange->preferred_loc;
2762 	} else if (prange->preferred_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
2763 		preferred_node = svm_range_get_node_by_id(prange, prange->preferred_loc);
2764 		if (preferred_node && svm_nodes_in_same_hive(node, preferred_node))
2765 			return prange->preferred_loc;
2766 		/* fall through */
2767 	}
2768 
2769 	if (test_bit(*gpuidx, prange->bitmap_access))
2770 		return gpuid;
2771 
2772 	if (test_bit(*gpuidx, prange->bitmap_aip)) {
2773 		if (!prange->actual_loc)
2774 			return 0;
2775 
2776 		bo_node = svm_range_get_node_by_id(prange, prange->actual_loc);
2777 		if (bo_node && svm_nodes_in_same_hive(node, bo_node))
2778 			return prange->actual_loc;
2779 		else
2780 			return 0;
2781 	}
2782 
2783 	return -1;
2784 }
2785 
2786 static int
2787 svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
2788 			       unsigned long *start, unsigned long *last,
2789 			       bool *is_heap_stack)
2790 {
2791 	struct vm_area_struct *vma;
2792 	struct interval_tree_node *node;
2793 	struct rb_node *rb_node;
2794 	unsigned long start_limit, end_limit;
2795 
2796 	vma = vma_lookup(p->mm, addr << PAGE_SHIFT);
2797 	if (!vma) {
2798 		pr_debug("VMA does not exist in address [0x%llx]\n", addr);
2799 		return -EFAULT;
2800 	}
2801 
2802 	*is_heap_stack = vma_is_initial_heap(vma) || vma_is_initial_stack(vma);
2803 
2804 	start_limit = max(vma->vm_start >> PAGE_SHIFT,
2805 		      (unsigned long)ALIGN_DOWN(addr, 1UL << p->svms.default_granularity));
2806 	end_limit = min(vma->vm_end >> PAGE_SHIFT,
2807 		    (unsigned long)ALIGN(addr + 1, 1UL << p->svms.default_granularity));
2808 
2809 	/* First range that starts after the fault address */
2810 	node = interval_tree_iter_first(&p->svms.objects, addr + 1, ULONG_MAX);
2811 	if (node) {
2812 		end_limit = min(end_limit, node->start);
2813 		/* Last range that ends before the fault address */
2814 		rb_node = rb_prev(&node->rb);
2815 	} else {
2816 		/* Last range must end before addr because
2817 		 * there was no range after addr
2818 		 */
2819 		rb_node = rb_last(&p->svms.objects.rb_root);
2820 	}
2821 	if (rb_node) {
2822 		node = container_of(rb_node, struct interval_tree_node, rb);
2823 		if (node->last >= addr) {
2824 			WARN(1, "Overlap with prev node and page fault addr\n");
2825 			return -EFAULT;
2826 		}
2827 		start_limit = max(start_limit, node->last + 1);
2828 	}
2829 
2830 	*start = start_limit;
2831 	*last = end_limit - 1;
2832 
2833 	pr_debug("vma [0x%lx 0x%lx] range [0x%lx 0x%lx] is_heap_stack %d\n",
2834 		 vma->vm_start >> PAGE_SHIFT, vma->vm_end >> PAGE_SHIFT,
2835 		 *start, *last, *is_heap_stack);
2836 
2837 	return 0;
2838 }
2839 
2840 static int
2841 svm_range_check_vm_userptr(struct kfd_process *p, uint64_t start, uint64_t last,
2842 			   uint64_t *bo_s, uint64_t *bo_l)
2843 {
2844 	struct amdgpu_bo_va_mapping *mapping;
2845 	struct interval_tree_node *node;
2846 	struct amdgpu_bo *bo = NULL;
2847 	unsigned long userptr;
2848 	uint32_t i;
2849 	int r;
2850 
2851 	for (i = 0; i < p->n_pdds; i++) {
2852 		struct amdgpu_vm *vm;
2853 
2854 		if (!p->pdds[i]->drm_priv)
2855 			continue;
2856 
2857 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
2858 		r = amdgpu_bo_reserve(vm->root.bo, false);
2859 		if (r)
2860 			return r;
2861 
2862 		/* Check userptr by searching entire vm->va interval tree */
2863 		node = interval_tree_iter_first(&vm->va, 0, ~0ULL);
2864 		while (node) {
2865 			mapping = container_of((struct rb_node *)node,
2866 					       struct amdgpu_bo_va_mapping, rb);
2867 			bo = mapping->bo_va->base.bo;
2868 
2869 			if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm,
2870 							 start << PAGE_SHIFT,
2871 							 last << PAGE_SHIFT,
2872 							 &userptr)) {
2873 				node = interval_tree_iter_next(node, 0, ~0ULL);
2874 				continue;
2875 			}
2876 
2877 			pr_debug("[0x%llx 0x%llx] already userptr mapped\n",
2878 				 start, last);
2879 			if (bo_s && bo_l) {
2880 				*bo_s = userptr >> PAGE_SHIFT;
2881 				*bo_l = *bo_s + bo->tbo.ttm->num_pages - 1;
2882 			}
2883 			amdgpu_bo_unreserve(vm->root.bo);
2884 			return -EADDRINUSE;
2885 		}
2886 		amdgpu_bo_unreserve(vm->root.bo);
2887 	}
2888 	return 0;
2889 }
2890 
2891 static struct
2892 svm_range *svm_range_create_unregistered_range(struct kfd_node *node,
2893 						struct kfd_process *p,
2894 						struct mm_struct *mm,
2895 						int64_t addr)
2896 {
2897 	struct svm_range *prange = NULL;
2898 	unsigned long start, last;
2899 	uint32_t gpuid, gpuidx;
2900 	bool is_heap_stack;
2901 	uint64_t bo_s = 0;
2902 	uint64_t bo_l = 0;
2903 	int r;
2904 
2905 	if (svm_range_get_range_boundaries(p, addr, &start, &last,
2906 					   &is_heap_stack))
2907 		return NULL;
2908 
2909 	r = svm_range_check_vm(p, start, last, &bo_s, &bo_l);
2910 	if (r != -EADDRINUSE)
2911 		r = svm_range_check_vm_userptr(p, start, last, &bo_s, &bo_l);
2912 
2913 	if (r == -EADDRINUSE) {
2914 		if (addr >= bo_s && addr <= bo_l)
2915 			return NULL;
2916 
2917 		/* Create one page svm range if 2MB range overlapping */
2918 		start = addr;
2919 		last = addr;
2920 	}
2921 
2922 	prange = svm_range_new(&p->svms, start, last, true);
2923 	if (!prange) {
2924 		pr_debug("Failed to create prange in address [0x%llx]\n", addr);
2925 		return NULL;
2926 	}
2927 	if (kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx)) {
2928 		pr_debug("failed to get gpuid from kgd\n");
2929 		svm_range_free(prange, true);
2930 		return NULL;
2931 	}
2932 
2933 	if (is_heap_stack)
2934 		prange->preferred_loc = KFD_IOCTL_SVM_LOCATION_SYSMEM;
2935 
2936 	svm_range_add_to_svms(prange);
2937 	svm_range_add_notifier_locked(mm, prange);
2938 
2939 	return prange;
2940 }
2941 
2942 /* svm_range_skip_recover - decide if prange can be recovered
2943  * @prange: svm range structure
2944  *
2945  * GPU vm retry fault handle skip recover the range for cases:
2946  * 1. prange is on deferred list to be removed after unmap, it is stale fault,
2947  *    deferred list work will drain the stale fault before free the prange.
2948  * 2. prange is on deferred list to add interval notifier after split, or
2949  * 3. prange is child range, it is split from parent prange, recover later
2950  *    after interval notifier is added.
2951  *
2952  * Return: true to skip recover, false to recover
2953  */
2954 static bool svm_range_skip_recover(struct svm_range *prange)
2955 {
2956 	struct svm_range_list *svms = prange->svms;
2957 
2958 	spin_lock(&svms->deferred_list_lock);
2959 	if (list_empty(&prange->deferred_list) &&
2960 	    list_empty(&prange->child_list)) {
2961 		spin_unlock(&svms->deferred_list_lock);
2962 		return false;
2963 	}
2964 	spin_unlock(&svms->deferred_list_lock);
2965 
2966 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2967 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] unmapped\n",
2968 			 svms, prange, prange->start, prange->last);
2969 		return true;
2970 	}
2971 	if (prange->work_item.op == SVM_OP_ADD_RANGE_AND_MAP ||
2972 	    prange->work_item.op == SVM_OP_ADD_RANGE) {
2973 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] not added yet\n",
2974 			 svms, prange, prange->start, prange->last);
2975 		return true;
2976 	}
2977 	return false;
2978 }
2979 
2980 static void
2981 svm_range_count_fault(struct kfd_node *node, struct kfd_process *p,
2982 		      int32_t gpuidx)
2983 {
2984 	struct kfd_process_device *pdd;
2985 
2986 	/* fault is on different page of same range
2987 	 * or fault is skipped to recover later
2988 	 * or fault is on invalid virtual address
2989 	 */
2990 	if (gpuidx == MAX_GPU_INSTANCE) {
2991 		uint32_t gpuid;
2992 		int r;
2993 
2994 		r = kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx);
2995 		if (r < 0)
2996 			return;
2997 	}
2998 
2999 	/* fault is recovered
3000 	 * or fault cannot recover because GPU no access on the range
3001 	 */
3002 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
3003 	if (pdd)
3004 		WRITE_ONCE(pdd->faults, pdd->faults + 1);
3005 }
3006 
3007 static bool
3008 svm_fault_allowed(struct vm_area_struct *vma, bool write_fault)
3009 {
3010 	unsigned long requested = VM_READ;
3011 
3012 	if (write_fault)
3013 		requested |= VM_WRITE;
3014 
3015 	pr_debug("requested 0x%lx, vma permission flags 0x%lx\n", requested,
3016 		vma->vm_flags);
3017 	return (vma->vm_flags & requested) == requested;
3018 }
3019 
3020 int
3021 svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
3022 			uint32_t vmid, uint32_t node_id,
3023 			uint64_t addr, uint64_t ts, bool write_fault)
3024 {
3025 	unsigned long start, last, size;
3026 	struct mm_struct *mm = NULL;
3027 	struct svm_range_list *svms;
3028 	struct svm_range *prange;
3029 	struct kfd_process *p;
3030 	ktime_t timestamp = ktime_get_boottime();
3031 	struct kfd_node *node;
3032 	int32_t best_loc;
3033 	int32_t gpuid, gpuidx = MAX_GPU_INSTANCE;
3034 	bool write_locked = false;
3035 	struct vm_area_struct *vma;
3036 	bool migration = false;
3037 	int r = 0;
3038 
3039 	if (!KFD_IS_SVM_API_SUPPORTED(adev)) {
3040 		pr_debug("device does not support SVM\n");
3041 		return -EFAULT;
3042 	}
3043 
3044 	p = kfd_lookup_process_by_pasid(pasid, NULL);
3045 	if (!p) {
3046 		pr_debug("kfd process not founded pasid 0x%x\n", pasid);
3047 		return 0;
3048 	}
3049 	svms = &p->svms;
3050 
3051 	pr_debug("restoring svms 0x%p fault address 0x%llx\n", svms, addr);
3052 
3053 	if (atomic_read(&svms->drain_pagefaults)) {
3054 		pr_debug("page fault handling disabled, drop fault 0x%llx\n", addr);
3055 		r = 0;
3056 		goto out;
3057 	}
3058 
3059 	node = kfd_node_by_irq_ids(adev, node_id, vmid);
3060 	if (!node) {
3061 		pr_debug("kfd node does not exist node_id: %d, vmid: %d\n", node_id,
3062 			 vmid);
3063 		r = -EFAULT;
3064 		goto out;
3065 	}
3066 
3067 	if (kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx)) {
3068 		pr_debug("failed to get gpuid/gpuidex for node_id: %d\n", node_id);
3069 		r = -EFAULT;
3070 		goto out;
3071 	}
3072 
3073 	if (!p->xnack_enabled) {
3074 		pr_debug("XNACK not enabled for pasid 0x%x\n", pasid);
3075 		r = -EFAULT;
3076 		goto out;
3077 	}
3078 
3079 	/* p->lead_thread is available as kfd_process_wq_release flush the work
3080 	 * before releasing task ref.
3081 	 */
3082 	mm = get_task_mm(p->lead_thread);
3083 	if (!mm) {
3084 		pr_debug("svms 0x%p failed to get mm\n", svms);
3085 		r = 0;
3086 		goto out;
3087 	}
3088 
3089 	mmap_read_lock(mm);
3090 retry_write_locked:
3091 	mutex_lock(&svms->lock);
3092 
3093 	/* check if this page fault time stamp is before svms->checkpoint_ts */
3094 	if (svms->checkpoint_ts[gpuidx] != 0) {
3095 		if (amdgpu_ih_ts_after_or_equal(ts,  svms->checkpoint_ts[gpuidx])) {
3096 			pr_debug("draining retry fault, drop fault 0x%llx\n", addr);
3097 			if (write_locked)
3098 				mmap_write_downgrade(mm);
3099 			r = -EAGAIN;
3100 			goto out_unlock_svms;
3101 		} else {
3102 			/* ts is after svms->checkpoint_ts now, reset svms->checkpoint_ts
3103 			 * to zero to avoid following ts wrap around give wrong comparing
3104 			 */
3105 			svms->checkpoint_ts[gpuidx] = 0;
3106 		}
3107 	}
3108 
3109 	prange = svm_range_from_addr(svms, addr, NULL);
3110 	if (!prange) {
3111 		pr_debug("failed to find prange svms 0x%p address [0x%llx]\n",
3112 			 svms, addr);
3113 		if (!write_locked) {
3114 			/* Need the write lock to create new range with MMU notifier.
3115 			 * Also flush pending deferred work to make sure the interval
3116 			 * tree is up to date before we add a new range
3117 			 */
3118 			mutex_unlock(&svms->lock);
3119 			mmap_read_unlock(mm);
3120 			mmap_write_lock(mm);
3121 			write_locked = true;
3122 			goto retry_write_locked;
3123 		}
3124 		prange = svm_range_create_unregistered_range(node, p, mm, addr);
3125 		if (!prange) {
3126 			pr_debug("failed to create unregistered range svms 0x%p address [0x%llx]\n",
3127 				 svms, addr);
3128 			mmap_write_downgrade(mm);
3129 			r = -EFAULT;
3130 			goto out_unlock_svms;
3131 		}
3132 	}
3133 	if (write_locked)
3134 		mmap_write_downgrade(mm);
3135 
3136 	mutex_lock(&prange->migrate_mutex);
3137 
3138 	if (svm_range_skip_recover(prange)) {
3139 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
3140 		r = 0;
3141 		goto out_unlock_range;
3142 	}
3143 
3144 	/* skip duplicate vm fault on different pages of same range */
3145 	if (ktime_before(timestamp, ktime_add_ns(prange->validate_timestamp,
3146 				AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING))) {
3147 		pr_debug("svms 0x%p [0x%lx %lx] already restored\n",
3148 			 svms, prange->start, prange->last);
3149 		r = 0;
3150 		goto out_unlock_range;
3151 	}
3152 
3153 	/* __do_munmap removed VMA, return success as we are handling stale
3154 	 * retry fault.
3155 	 */
3156 	vma = vma_lookup(mm, addr << PAGE_SHIFT);
3157 	if (!vma) {
3158 		pr_debug("address 0x%llx VMA is removed\n", addr);
3159 		r = 0;
3160 		goto out_unlock_range;
3161 	}
3162 
3163 	if (!svm_fault_allowed(vma, write_fault)) {
3164 		pr_debug("fault addr 0x%llx no %s permission\n", addr,
3165 			write_fault ? "write" : "read");
3166 		r = -EPERM;
3167 		goto out_unlock_range;
3168 	}
3169 
3170 	best_loc = svm_range_best_restore_location(prange, node, &gpuidx);
3171 	if (best_loc == -1) {
3172 		pr_debug("svms %p failed get best restore loc [0x%lx 0x%lx]\n",
3173 			 svms, prange->start, prange->last);
3174 		r = -EACCES;
3175 		goto out_unlock_range;
3176 	}
3177 
3178 	pr_debug("svms %p [0x%lx 0x%lx] best restore 0x%x, actual loc 0x%x\n",
3179 		 svms, prange->start, prange->last, best_loc,
3180 		 prange->actual_loc);
3181 
3182 	kfd_smi_event_page_fault_start(node, p->lead_thread->pid, addr,
3183 				       write_fault, timestamp);
3184 
3185 	/* Align migration range start and size to granularity size */
3186 	size = 1UL << prange->granularity;
3187 	start = max_t(unsigned long, ALIGN_DOWN(addr, size), prange->start);
3188 	last = min_t(unsigned long, ALIGN(addr + 1, size) - 1, prange->last);
3189 	if (prange->actual_loc != 0 || best_loc != 0) {
3190 		if (best_loc) {
3191 			r = svm_migrate_to_vram(prange, best_loc, start, last,
3192 					mm, KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU);
3193 			if (r) {
3194 				pr_debug("svm_migrate_to_vram failed (%d) at %llx, falling back to system memory\n",
3195 					 r, addr);
3196 				/* Fallback to system memory if migration to
3197 				 * VRAM failed
3198 				 */
3199 				if (prange->actual_loc && prange->actual_loc != best_loc)
3200 					r = svm_migrate_vram_to_ram(prange, mm, start, last,
3201 						KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU, NULL);
3202 				else
3203 					r = 0;
3204 			}
3205 		} else {
3206 			r = svm_migrate_vram_to_ram(prange, mm, start, last,
3207 					KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU, NULL);
3208 		}
3209 		if (r) {
3210 			pr_debug("failed %d to migrate svms %p [0x%lx 0x%lx]\n",
3211 				 r, svms, start, last);
3212 			goto out_migrate_fail;
3213 		} else {
3214 			migration = true;
3215 		}
3216 	}
3217 
3218 	r = svm_range_validate_and_map(mm, start, last, prange, gpuidx, false,
3219 				       false, false);
3220 	if (r)
3221 		pr_debug("failed %d to map svms 0x%p [0x%lx 0x%lx] to gpus\n",
3222 			 r, svms, start, last);
3223 
3224 out_migrate_fail:
3225 	kfd_smi_event_page_fault_end(node, p->lead_thread->pid, addr,
3226 				     migration);
3227 
3228 out_unlock_range:
3229 	mutex_unlock(&prange->migrate_mutex);
3230 out_unlock_svms:
3231 	mutex_unlock(&svms->lock);
3232 	mmap_read_unlock(mm);
3233 
3234 	if (r != -EAGAIN)
3235 		svm_range_count_fault(node, p, gpuidx);
3236 
3237 	mmput(mm);
3238 out:
3239 	kfd_unref_process(p);
3240 
3241 	if (r == -EAGAIN) {
3242 		pr_debug("recover vm fault later\n");
3243 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
3244 		r = 0;
3245 	}
3246 	return r;
3247 }
3248 
3249 int
3250 svm_range_switch_xnack_reserve_mem(struct kfd_process *p, bool xnack_enabled)
3251 {
3252 	struct svm_range *prange, *pchild;
3253 	uint64_t reserved_size = 0;
3254 	uint64_t size;
3255 	int r = 0;
3256 
3257 	pr_debug("switching xnack from %d to %d\n", p->xnack_enabled, xnack_enabled);
3258 
3259 	mutex_lock(&p->svms.lock);
3260 
3261 	list_for_each_entry(prange, &p->svms.list, list) {
3262 		svm_range_lock(prange);
3263 		list_for_each_entry(pchild, &prange->child_list, child_list) {
3264 			size = (pchild->last - pchild->start + 1) << PAGE_SHIFT;
3265 			if (xnack_enabled) {
3266 				amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3267 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3268 			} else {
3269 				r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3270 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3271 				if (r)
3272 					goto out_unlock;
3273 				reserved_size += size;
3274 			}
3275 		}
3276 
3277 		size = (prange->last - prange->start + 1) << PAGE_SHIFT;
3278 		if (xnack_enabled) {
3279 			amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3280 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3281 		} else {
3282 			r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3283 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3284 			if (r)
3285 				goto out_unlock;
3286 			reserved_size += size;
3287 		}
3288 out_unlock:
3289 		svm_range_unlock(prange);
3290 		if (r)
3291 			break;
3292 	}
3293 
3294 	if (r)
3295 		amdgpu_amdkfd_unreserve_mem_limit(NULL, reserved_size,
3296 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3297 	else
3298 		/* Change xnack mode must be inside svms lock, to avoid race with
3299 		 * svm_range_deferred_list_work unreserve memory in parallel.
3300 		 */
3301 		p->xnack_enabled = xnack_enabled;
3302 
3303 	mutex_unlock(&p->svms.lock);
3304 	return r;
3305 }
3306 
3307 void svm_range_list_fini(struct kfd_process *p)
3308 {
3309 	struct svm_range *prange;
3310 	struct svm_range *next;
3311 
3312 	pr_debug("process pid %d svms 0x%p\n", p->lead_thread->pid,
3313 		 &p->svms);
3314 
3315 	cancel_delayed_work_sync(&p->svms.restore_work);
3316 
3317 	/* Ensure list work is finished before process is destroyed */
3318 	flush_work(&p->svms.deferred_list_work);
3319 
3320 	/*
3321 	 * Ensure no retry fault comes in afterwards, as page fault handler will
3322 	 * not find kfd process and take mm lock to recover fault.
3323 	 * stop kfd page fault handing, then wait pending page faults got drained
3324 	 */
3325 	atomic_set(&p->svms.drain_pagefaults, 1);
3326 	svm_range_drain_retry_fault(&p->svms);
3327 
3328 	list_for_each_entry_safe(prange, next, &p->svms.list, list) {
3329 		svm_range_unlink(prange);
3330 		svm_range_remove_notifier(prange);
3331 		svm_range_free(prange, true);
3332 	}
3333 
3334 	mutex_destroy(&p->svms.lock);
3335 
3336 	pr_debug("process pid %d svms 0x%p done\n",
3337 		p->lead_thread->pid, &p->svms);
3338 }
3339 
3340 int svm_range_list_init(struct kfd_process *p)
3341 {
3342 	struct svm_range_list *svms = &p->svms;
3343 	int i;
3344 
3345 	svms->objects = RB_ROOT_CACHED;
3346 	mutex_init(&svms->lock);
3347 	INIT_LIST_HEAD(&svms->list);
3348 	atomic_set(&svms->evicted_ranges, 0);
3349 	atomic_set(&svms->drain_pagefaults, 0);
3350 	INIT_DELAYED_WORK(&svms->restore_work, svm_range_restore_work);
3351 	INIT_WORK(&svms->deferred_list_work, svm_range_deferred_list_work);
3352 	INIT_LIST_HEAD(&svms->deferred_range_list);
3353 	INIT_LIST_HEAD(&svms->criu_svm_metadata_list);
3354 	spin_lock_init(&svms->deferred_list_lock);
3355 
3356 	for (i = 0; i < p->n_pdds; i++)
3357 		if (KFD_IS_SVM_API_SUPPORTED(p->pdds[i]->dev->adev))
3358 			bitmap_set(svms->bitmap_supported, i, 1);
3359 
3360 	 /* Value of default granularity cannot exceed 0x1B, the
3361 	  * number of pages supported by a 4-level paging table
3362 	  */
3363 	svms->default_granularity = min_t(u8, amdgpu_svm_default_granularity, 0x1B);
3364 	pr_debug("Default SVM Granularity to use: %d\n", svms->default_granularity);
3365 
3366 	return 0;
3367 }
3368 
3369 /**
3370  * svm_range_check_vm - check if virtual address range mapped already
3371  * @p: current kfd_process
3372  * @start: range start address, in pages
3373  * @last: range last address, in pages
3374  * @bo_s: mapping start address in pages if address range already mapped
3375  * @bo_l: mapping last address in pages if address range already mapped
3376  *
3377  * The purpose is to avoid virtual address ranges already allocated by
3378  * kfd_ioctl_alloc_memory_of_gpu ioctl.
3379  * It looks for each pdd in the kfd_process.
3380  *
3381  * Context: Process context
3382  *
3383  * Return 0 - OK, if the range is not mapped.
3384  * Otherwise error code:
3385  * -EADDRINUSE - if address is mapped already by kfd_ioctl_alloc_memory_of_gpu
3386  * -ERESTARTSYS - A wait for the buffer to become unreserved was interrupted by
3387  * a signal. Release all buffer reservations and return to user-space.
3388  */
3389 static int
3390 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
3391 		   uint64_t *bo_s, uint64_t *bo_l)
3392 {
3393 	struct amdgpu_bo_va_mapping *mapping;
3394 	struct interval_tree_node *node;
3395 	uint32_t i;
3396 	int r;
3397 
3398 	for (i = 0; i < p->n_pdds; i++) {
3399 		struct amdgpu_vm *vm;
3400 
3401 		if (!p->pdds[i]->drm_priv)
3402 			continue;
3403 
3404 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
3405 		r = amdgpu_bo_reserve(vm->root.bo, false);
3406 		if (r)
3407 			return r;
3408 
3409 		node = interval_tree_iter_first(&vm->va, start, last);
3410 		if (node) {
3411 			pr_debug("range [0x%llx 0x%llx] already TTM mapped\n",
3412 				 start, last);
3413 			mapping = container_of((struct rb_node *)node,
3414 					       struct amdgpu_bo_va_mapping, rb);
3415 			if (bo_s && bo_l) {
3416 				*bo_s = mapping->start;
3417 				*bo_l = mapping->last;
3418 			}
3419 			amdgpu_bo_unreserve(vm->root.bo);
3420 			return -EADDRINUSE;
3421 		}
3422 		amdgpu_bo_unreserve(vm->root.bo);
3423 	}
3424 
3425 	return 0;
3426 }
3427 
3428 /**
3429  * svm_range_is_valid - check if virtual address range is valid
3430  * @p: current kfd_process
3431  * @start: range start address, in pages
3432  * @size: range size, in pages
3433  *
3434  * Valid virtual address range means it belongs to one or more VMAs
3435  *
3436  * Context: Process context
3437  *
3438  * Return:
3439  *  0 - OK, otherwise error code
3440  */
3441 static int
3442 svm_range_is_valid(struct kfd_process *p, uint64_t start, uint64_t size)
3443 {
3444 	const unsigned long device_vma = VM_IO | VM_PFNMAP | VM_MIXEDMAP;
3445 	struct vm_area_struct *vma;
3446 	unsigned long end;
3447 	unsigned long start_unchg = start;
3448 
3449 	start <<= PAGE_SHIFT;
3450 	end = start + (size << PAGE_SHIFT);
3451 	do {
3452 		vma = vma_lookup(p->mm, start);
3453 		if (!vma || (vma->vm_flags & device_vma))
3454 			return -EFAULT;
3455 		start = min(end, vma->vm_end);
3456 	} while (start < end);
3457 
3458 	return svm_range_check_vm(p, start_unchg, (end - 1) >> PAGE_SHIFT, NULL,
3459 				  NULL);
3460 }
3461 
3462 /**
3463  * svm_range_best_prefetch_location - decide the best prefetch location
3464  * @prange: svm range structure
3465  *
3466  * For xnack off:
3467  * If range map to single GPU, the best prefetch location is prefetch_loc, which
3468  * can be CPU or GPU.
3469  *
3470  * If range is ACCESS or ACCESS_IN_PLACE by mGPUs, only if mGPU connection on
3471  * XGMI same hive, the best prefetch location is prefetch_loc GPU, othervise
3472  * the best prefetch location is always CPU, because GPU can not have coherent
3473  * mapping VRAM of other GPUs even with large-BAR PCIe connection.
3474  *
3475  * For xnack on:
3476  * If range is not ACCESS_IN_PLACE by mGPUs, the best prefetch location is
3477  * prefetch_loc, other GPU access will generate vm fault and trigger migration.
3478  *
3479  * If range is ACCESS_IN_PLACE by mGPUs, only if mGPU connection on XGMI same
3480  * hive, the best prefetch location is prefetch_loc GPU, otherwise the best
3481  * prefetch location is always CPU.
3482  *
3483  * Context: Process context
3484  *
3485  * Return:
3486  * 0 for CPU or GPU id
3487  */
3488 static uint32_t
3489 svm_range_best_prefetch_location(struct svm_range *prange)
3490 {
3491 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
3492 	uint32_t best_loc = prange->prefetch_loc;
3493 	struct kfd_process_device *pdd;
3494 	struct kfd_node *bo_node;
3495 	struct kfd_process *p;
3496 	uint32_t gpuidx;
3497 
3498 	p = container_of(prange->svms, struct kfd_process, svms);
3499 
3500 	if (!best_loc || best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED)
3501 		goto out;
3502 
3503 	bo_node = svm_range_get_node_by_id(prange, best_loc);
3504 	if (!bo_node) {
3505 		WARN_ONCE(1, "failed to get valid kfd node at id%x\n", best_loc);
3506 		best_loc = 0;
3507 		goto out;
3508 	}
3509 
3510 	if (bo_node->adev->apu_prefer_gtt) {
3511 		best_loc = 0;
3512 		goto out;
3513 	}
3514 
3515 	if (p->xnack_enabled)
3516 		bitmap_copy(bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
3517 	else
3518 		bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
3519 			  MAX_GPU_INSTANCE);
3520 
3521 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
3522 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
3523 		if (!pdd) {
3524 			pr_debug("failed to get device by idx 0x%x\n", gpuidx);
3525 			continue;
3526 		}
3527 
3528 		if (pdd->dev->adev == bo_node->adev)
3529 			continue;
3530 
3531 		if (!svm_nodes_in_same_hive(pdd->dev, bo_node)) {
3532 			best_loc = 0;
3533 			break;
3534 		}
3535 	}
3536 
3537 out:
3538 	pr_debug("xnack %d svms 0x%p [0x%lx 0x%lx] best loc 0x%x\n",
3539 		 p->xnack_enabled, &p->svms, prange->start, prange->last,
3540 		 best_loc);
3541 
3542 	return best_loc;
3543 }
3544 
3545 /* svm_range_trigger_migration - start page migration if prefetch loc changed
3546  * @mm: current process mm_struct
3547  * @prange: svm range structure
3548  * @migrated: output, true if migration is triggered
3549  *
3550  * If range perfetch_loc is GPU, actual loc is cpu 0, then migrate the range
3551  * from ram to vram.
3552  * If range prefetch_loc is cpu 0, actual loc is GPU, then migrate the range
3553  * from vram to ram.
3554  *
3555  * If GPU vm fault retry is not enabled, migration interact with MMU notifier
3556  * and restore work:
3557  * 1. migrate_vma_setup invalidate pages, MMU notifier callback svm_range_evict
3558  *    stops all queues, schedule restore work
3559  * 2. svm_range_restore_work wait for migration is done by
3560  *    a. svm_range_validate_vram takes prange->migrate_mutex
3561  *    b. svm_range_validate_ram HMM get pages wait for CPU fault handle returns
3562  * 3. restore work update mappings of GPU, resume all queues.
3563  *
3564  * Context: Process context
3565  *
3566  * Return:
3567  * 0 - OK, otherwise - error code of migration
3568  */
3569 static int
3570 svm_range_trigger_migration(struct mm_struct *mm, struct svm_range *prange,
3571 			    bool *migrated)
3572 {
3573 	uint32_t best_loc;
3574 	int r = 0;
3575 
3576 	*migrated = false;
3577 	best_loc = svm_range_best_prefetch_location(prange);
3578 
3579 	/* when best_loc is a gpu node and same as prange->actual_loc
3580 	 * we still need do migration as prange->actual_loc !=0 does
3581 	 * not mean all pages in prange are vram. hmm migrate will pick
3582 	 * up right pages during migration.
3583 	 */
3584 	if ((best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED) ||
3585 	    (best_loc == 0 && prange->actual_loc == 0))
3586 		return 0;
3587 
3588 	if (!best_loc) {
3589 		r = svm_migrate_vram_to_ram(prange, mm, prange->start, prange->last,
3590 					KFD_MIGRATE_TRIGGER_PREFETCH, NULL);
3591 		*migrated = !r;
3592 		return r;
3593 	}
3594 
3595 	r = svm_migrate_to_vram(prange, best_loc, prange->start, prange->last,
3596 				mm, KFD_MIGRATE_TRIGGER_PREFETCH);
3597 	*migrated = !r;
3598 
3599 	return 0;
3600 }
3601 
3602 int svm_range_schedule_evict_svm_bo(struct amdgpu_amdkfd_fence *fence)
3603 {
3604 	/* Dereferencing fence->svm_bo is safe here because the fence hasn't
3605 	 * signaled yet and we're under the protection of the fence->lock.
3606 	 * After the fence is signaled in svm_range_bo_release, we cannot get
3607 	 * here any more.
3608 	 *
3609 	 * Reference is dropped in svm_range_evict_svm_bo_worker.
3610 	 */
3611 	if (svm_bo_ref_unless_zero(fence->svm_bo)) {
3612 		WRITE_ONCE(fence->svm_bo->evicting, 1);
3613 		schedule_work(&fence->svm_bo->eviction_work);
3614 	}
3615 
3616 	return 0;
3617 }
3618 
3619 static void svm_range_evict_svm_bo_worker(struct work_struct *work)
3620 {
3621 	struct svm_range_bo *svm_bo;
3622 	struct mm_struct *mm;
3623 	int r = 0;
3624 
3625 	svm_bo = container_of(work, struct svm_range_bo, eviction_work);
3626 
3627 	if (mmget_not_zero(svm_bo->eviction_fence->mm)) {
3628 		mm = svm_bo->eviction_fence->mm;
3629 	} else {
3630 		svm_range_bo_unref(svm_bo);
3631 		return;
3632 	}
3633 
3634 	mmap_read_lock(mm);
3635 	spin_lock(&svm_bo->list_lock);
3636 	while (!list_empty(&svm_bo->range_list) && !r) {
3637 		struct svm_range *prange =
3638 				list_first_entry(&svm_bo->range_list,
3639 						struct svm_range, svm_bo_list);
3640 		int retries = 3;
3641 
3642 		list_del_init(&prange->svm_bo_list);
3643 		spin_unlock(&svm_bo->list_lock);
3644 
3645 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
3646 			 prange->start, prange->last);
3647 
3648 		mutex_lock(&prange->migrate_mutex);
3649 		do {
3650 			/* migrate all vram pages in this prange to sys ram
3651 			 * after that prange->actual_loc should be zero
3652 			 */
3653 			r = svm_migrate_vram_to_ram(prange, mm,
3654 					prange->start, prange->last,
3655 					KFD_MIGRATE_TRIGGER_TTM_EVICTION, NULL);
3656 		} while (!r && prange->actual_loc && --retries);
3657 
3658 		if (!r && prange->actual_loc)
3659 			pr_info_once("Migration failed during eviction");
3660 
3661 		if (!prange->actual_loc) {
3662 			mutex_lock(&prange->lock);
3663 			prange->svm_bo = NULL;
3664 			mutex_unlock(&prange->lock);
3665 		}
3666 		mutex_unlock(&prange->migrate_mutex);
3667 
3668 		spin_lock(&svm_bo->list_lock);
3669 	}
3670 	spin_unlock(&svm_bo->list_lock);
3671 	mmap_read_unlock(mm);
3672 	mmput(mm);
3673 
3674 	dma_fence_signal(&svm_bo->eviction_fence->base);
3675 
3676 	/* This is the last reference to svm_bo, after svm_range_vram_node_free
3677 	 * has been called in svm_migrate_vram_to_ram
3678 	 */
3679 	WARN_ONCE(!r && kref_read(&svm_bo->kref) != 1, "This was not the last reference\n");
3680 	svm_range_bo_unref(svm_bo);
3681 }
3682 
3683 static int
3684 svm_range_set_attr(struct kfd_process *p, struct mm_struct *mm,
3685 		   uint64_t start, uint64_t size, uint32_t nattr,
3686 		   struct kfd_ioctl_svm_attribute *attrs)
3687 {
3688 	struct amdkfd_process_info *process_info = p->kgd_process_info;
3689 	struct list_head update_list;
3690 	struct list_head insert_list;
3691 	struct list_head remove_list;
3692 	struct list_head remap_list;
3693 	struct svm_range_list *svms;
3694 	struct svm_range *prange;
3695 	struct svm_range *next;
3696 	bool update_mapping = false;
3697 	bool flush_tlb;
3698 	int r, ret = 0;
3699 
3700 	pr_debug("process pid %d svms 0x%p [0x%llx 0x%llx] pages 0x%llx\n",
3701 		 p->lead_thread->pid, &p->svms, start, start + size - 1, size);
3702 
3703 	r = svm_range_check_attr(p, nattr, attrs);
3704 	if (r)
3705 		return r;
3706 
3707 	svms = &p->svms;
3708 
3709 	mutex_lock(&process_info->lock);
3710 
3711 	svm_range_list_lock_and_flush_work(svms, mm);
3712 
3713 	r = svm_range_is_valid(p, start, size);
3714 	if (r) {
3715 		pr_debug("invalid range r=%d\n", r);
3716 		mmap_write_unlock(mm);
3717 		goto out;
3718 	}
3719 
3720 	mutex_lock(&svms->lock);
3721 
3722 	/* Add new range and split existing ranges as needed */
3723 	r = svm_range_add(p, start, size, nattr, attrs, &update_list,
3724 			  &insert_list, &remove_list, &remap_list);
3725 	if (r) {
3726 		mutex_unlock(&svms->lock);
3727 		mmap_write_unlock(mm);
3728 		goto out;
3729 	}
3730 	/* Apply changes as a transaction */
3731 	list_for_each_entry_safe(prange, next, &insert_list, list) {
3732 		svm_range_add_to_svms(prange);
3733 		svm_range_add_notifier_locked(mm, prange);
3734 	}
3735 	list_for_each_entry(prange, &update_list, update_list) {
3736 		svm_range_apply_attrs(p, prange, nattr, attrs, &update_mapping);
3737 		/* TODO: unmap ranges from GPU that lost access */
3738 	}
3739 	update_mapping |= !p->xnack_enabled && !list_empty(&remap_list);
3740 
3741 	list_for_each_entry_safe(prange, next, &remove_list, update_list) {
3742 		pr_debug("unlink old 0x%p prange 0x%p [0x%lx 0x%lx]\n",
3743 			 prange->svms, prange, prange->start,
3744 			 prange->last);
3745 		svm_range_unlink(prange);
3746 		svm_range_remove_notifier(prange);
3747 		svm_range_free(prange, false);
3748 	}
3749 
3750 	mmap_write_downgrade(mm);
3751 	/* Trigger migrations and revalidate and map to GPUs as needed. If
3752 	 * this fails we may be left with partially completed actions. There
3753 	 * is no clean way of rolling back to the previous state in such a
3754 	 * case because the rollback wouldn't be guaranteed to work either.
3755 	 */
3756 	list_for_each_entry(prange, &update_list, update_list) {
3757 		bool migrated;
3758 
3759 		mutex_lock(&prange->migrate_mutex);
3760 
3761 		r = svm_range_trigger_migration(mm, prange, &migrated);
3762 		if (r)
3763 			goto out_unlock_range;
3764 
3765 		if (migrated && (!p->xnack_enabled ||
3766 		    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) &&
3767 		    prange->mapped_to_gpu) {
3768 			pr_debug("restore_work will update mappings of GPUs\n");
3769 			mutex_unlock(&prange->migrate_mutex);
3770 			continue;
3771 		}
3772 
3773 		if (!migrated && !update_mapping) {
3774 			mutex_unlock(&prange->migrate_mutex);
3775 			continue;
3776 		}
3777 
3778 		flush_tlb = !migrated && update_mapping && prange->mapped_to_gpu;
3779 
3780 		r = svm_range_validate_and_map(mm, prange->start, prange->last, prange,
3781 					       MAX_GPU_INSTANCE, true, true, flush_tlb);
3782 		if (r)
3783 			pr_debug("failed %d to map svm range\n", r);
3784 
3785 out_unlock_range:
3786 		mutex_unlock(&prange->migrate_mutex);
3787 		if (r)
3788 			ret = r;
3789 	}
3790 
3791 	list_for_each_entry(prange, &remap_list, update_list) {
3792 		pr_debug("Remapping prange 0x%p [0x%lx 0x%lx]\n",
3793 			 prange, prange->start, prange->last);
3794 		mutex_lock(&prange->migrate_mutex);
3795 		r = svm_range_validate_and_map(mm,  prange->start, prange->last, prange,
3796 					       MAX_GPU_INSTANCE, true, true, prange->mapped_to_gpu);
3797 		if (r)
3798 			pr_debug("failed %d on remap svm range\n", r);
3799 		mutex_unlock(&prange->migrate_mutex);
3800 		if (r)
3801 			ret = r;
3802 	}
3803 
3804 	dynamic_svm_range_dump(svms);
3805 
3806 	mutex_unlock(&svms->lock);
3807 	mmap_read_unlock(mm);
3808 out:
3809 	mutex_unlock(&process_info->lock);
3810 
3811 	pr_debug("process pid %d svms 0x%p [0x%llx 0x%llx] done, r=%d\n",
3812 		 p->lead_thread->pid, &p->svms, start, start + size - 1, r);
3813 
3814 	return ret ? ret : r;
3815 }
3816 
3817 static int
3818 svm_range_get_attr(struct kfd_process *p, struct mm_struct *mm,
3819 		   uint64_t start, uint64_t size, uint32_t nattr,
3820 		   struct kfd_ioctl_svm_attribute *attrs)
3821 {
3822 	DECLARE_BITMAP(bitmap_access, MAX_GPU_INSTANCE);
3823 	DECLARE_BITMAP(bitmap_aip, MAX_GPU_INSTANCE);
3824 	bool get_preferred_loc = false;
3825 	bool get_prefetch_loc = false;
3826 	bool get_granularity = false;
3827 	bool get_accessible = false;
3828 	bool get_flags = false;
3829 	uint64_t last = start + size - 1UL;
3830 	uint8_t granularity = 0xff;
3831 	struct interval_tree_node *node;
3832 	struct svm_range_list *svms;
3833 	struct svm_range *prange;
3834 	uint32_t prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3835 	uint32_t location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3836 	uint32_t flags_and = 0xffffffff;
3837 	uint32_t flags_or = 0;
3838 	int gpuidx;
3839 	uint32_t i;
3840 	int r = 0;
3841 
3842 	pr_debug("svms 0x%p [0x%llx 0x%llx] nattr 0x%x\n", &p->svms, start,
3843 		 start + size - 1, nattr);
3844 
3845 	/* Flush pending deferred work to avoid racing with deferred actions from
3846 	 * previous memory map changes (e.g. munmap). Concurrent memory map changes
3847 	 * can still race with get_attr because we don't hold the mmap lock. But that
3848 	 * would be a race condition in the application anyway, and undefined
3849 	 * behaviour is acceptable in that case.
3850 	 */
3851 	flush_work(&p->svms.deferred_list_work);
3852 
3853 	mmap_read_lock(mm);
3854 	r = svm_range_is_valid(p, start, size);
3855 	mmap_read_unlock(mm);
3856 	if (r) {
3857 		pr_debug("invalid range r=%d\n", r);
3858 		return r;
3859 	}
3860 
3861 	for (i = 0; i < nattr; i++) {
3862 		switch (attrs[i].type) {
3863 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3864 			get_preferred_loc = true;
3865 			break;
3866 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3867 			get_prefetch_loc = true;
3868 			break;
3869 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3870 			get_accessible = true;
3871 			break;
3872 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3873 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3874 			get_flags = true;
3875 			break;
3876 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3877 			get_granularity = true;
3878 			break;
3879 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
3880 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
3881 			fallthrough;
3882 		default:
3883 			pr_debug("get invalid attr type 0x%x\n", attrs[i].type);
3884 			return -EINVAL;
3885 		}
3886 	}
3887 
3888 	svms = &p->svms;
3889 
3890 	mutex_lock(&svms->lock);
3891 
3892 	node = interval_tree_iter_first(&svms->objects, start, last);
3893 	if (!node) {
3894 		pr_debug("range attrs not found return default values\n");
3895 		svm_range_set_default_attributes(svms, &location, &prefetch_loc,
3896 						 &granularity, &flags_and);
3897 		flags_or = flags_and;
3898 		if (p->xnack_enabled)
3899 			bitmap_copy(bitmap_access, svms->bitmap_supported,
3900 				    MAX_GPU_INSTANCE);
3901 		else
3902 			bitmap_zero(bitmap_access, MAX_GPU_INSTANCE);
3903 		bitmap_zero(bitmap_aip, MAX_GPU_INSTANCE);
3904 		goto fill_values;
3905 	}
3906 	bitmap_copy(bitmap_access, svms->bitmap_supported, MAX_GPU_INSTANCE);
3907 	bitmap_copy(bitmap_aip, svms->bitmap_supported, MAX_GPU_INSTANCE);
3908 
3909 	while (node) {
3910 		struct interval_tree_node *next;
3911 
3912 		prange = container_of(node, struct svm_range, it_node);
3913 		next = interval_tree_iter_next(node, start, last);
3914 
3915 		if (get_preferred_loc) {
3916 			if (prange->preferred_loc ==
3917 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3918 			    (location != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3919 			     location != prange->preferred_loc)) {
3920 				location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3921 				get_preferred_loc = false;
3922 			} else {
3923 				location = prange->preferred_loc;
3924 			}
3925 		}
3926 		if (get_prefetch_loc) {
3927 			if (prange->prefetch_loc ==
3928 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3929 			    (prefetch_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3930 			     prefetch_loc != prange->prefetch_loc)) {
3931 				prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3932 				get_prefetch_loc = false;
3933 			} else {
3934 				prefetch_loc = prange->prefetch_loc;
3935 			}
3936 		}
3937 		if (get_accessible) {
3938 			bitmap_and(bitmap_access, bitmap_access,
3939 				   prange->bitmap_access, MAX_GPU_INSTANCE);
3940 			bitmap_and(bitmap_aip, bitmap_aip,
3941 				   prange->bitmap_aip, MAX_GPU_INSTANCE);
3942 		}
3943 		if (get_flags) {
3944 			flags_and &= prange->flags;
3945 			flags_or |= prange->flags;
3946 		}
3947 
3948 		if (get_granularity && prange->granularity < granularity)
3949 			granularity = prange->granularity;
3950 
3951 		node = next;
3952 	}
3953 fill_values:
3954 	mutex_unlock(&svms->lock);
3955 
3956 	for (i = 0; i < nattr; i++) {
3957 		switch (attrs[i].type) {
3958 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3959 			attrs[i].value = location;
3960 			break;
3961 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3962 			attrs[i].value = prefetch_loc;
3963 			break;
3964 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3965 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
3966 							       attrs[i].value);
3967 			if (gpuidx < 0) {
3968 				pr_debug("invalid gpuid %x\n", attrs[i].value);
3969 				return -EINVAL;
3970 			}
3971 			if (test_bit(gpuidx, bitmap_access))
3972 				attrs[i].type = KFD_IOCTL_SVM_ATTR_ACCESS;
3973 			else if (test_bit(gpuidx, bitmap_aip))
3974 				attrs[i].type =
3975 					KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE;
3976 			else
3977 				attrs[i].type = KFD_IOCTL_SVM_ATTR_NO_ACCESS;
3978 			break;
3979 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3980 			attrs[i].value = flags_and;
3981 			break;
3982 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3983 			attrs[i].value = ~flags_or;
3984 			break;
3985 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3986 			attrs[i].value = (uint32_t)granularity;
3987 			break;
3988 		}
3989 	}
3990 
3991 	return 0;
3992 }
3993 
3994 int kfd_criu_resume_svm(struct kfd_process *p)
3995 {
3996 	struct kfd_ioctl_svm_attribute *set_attr_new, *set_attr = NULL;
3997 	int nattr_common = 4, nattr_accessibility = 1;
3998 	struct criu_svm_metadata *criu_svm_md = NULL;
3999 	struct svm_range_list *svms = &p->svms;
4000 	struct criu_svm_metadata *next = NULL;
4001 	uint32_t set_flags = 0xffffffff;
4002 	int i, j, num_attrs, ret = 0;
4003 	uint64_t set_attr_size;
4004 	struct mm_struct *mm;
4005 
4006 	if (list_empty(&svms->criu_svm_metadata_list)) {
4007 		pr_debug("No SVM data from CRIU restore stage 2\n");
4008 		return ret;
4009 	}
4010 
4011 	mm = get_task_mm(p->lead_thread);
4012 	if (!mm) {
4013 		pr_err("failed to get mm for the target process\n");
4014 		return -ESRCH;
4015 	}
4016 
4017 	num_attrs = nattr_common + (nattr_accessibility * p->n_pdds);
4018 
4019 	i = j = 0;
4020 	list_for_each_entry(criu_svm_md, &svms->criu_svm_metadata_list, list) {
4021 		pr_debug("criu_svm_md[%d]\n\tstart: 0x%llx size: 0x%llx (npages)\n",
4022 			 i, criu_svm_md->data.start_addr, criu_svm_md->data.size);
4023 
4024 		for (j = 0; j < num_attrs; j++) {
4025 			pr_debug("\ncriu_svm_md[%d]->attrs[%d].type : 0x%x\ncriu_svm_md[%d]->attrs[%d].value : 0x%x\n",
4026 				 i, j, criu_svm_md->data.attrs[j].type,
4027 				 i, j, criu_svm_md->data.attrs[j].value);
4028 			switch (criu_svm_md->data.attrs[j].type) {
4029 			/* During Checkpoint operation, the query for
4030 			 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC attribute might
4031 			 * return KFD_IOCTL_SVM_LOCATION_UNDEFINED if they were
4032 			 * not used by the range which was checkpointed. Care
4033 			 * must be taken to not restore with an invalid value
4034 			 * otherwise the gpuidx value will be invalid and
4035 			 * set_attr would eventually fail so just replace those
4036 			 * with another dummy attribute such as
4037 			 * KFD_IOCTL_SVM_ATTR_SET_FLAGS.
4038 			 */
4039 			case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
4040 				if (criu_svm_md->data.attrs[j].value ==
4041 				    KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
4042 					criu_svm_md->data.attrs[j].type =
4043 						KFD_IOCTL_SVM_ATTR_SET_FLAGS;
4044 					criu_svm_md->data.attrs[j].value = 0;
4045 				}
4046 				break;
4047 			case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
4048 				set_flags = criu_svm_md->data.attrs[j].value;
4049 				break;
4050 			default:
4051 				break;
4052 			}
4053 		}
4054 
4055 		/* CLR_FLAGS is not available via get_attr during checkpoint but
4056 		 * it needs to be inserted before restoring the ranges so
4057 		 * allocate extra space for it before calling set_attr
4058 		 */
4059 		set_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4060 						(num_attrs + 1);
4061 		set_attr_new = krealloc(set_attr, set_attr_size,
4062 					    GFP_KERNEL);
4063 		if (!set_attr_new) {
4064 			ret = -ENOMEM;
4065 			goto exit;
4066 		}
4067 		set_attr = set_attr_new;
4068 
4069 		memcpy(set_attr, criu_svm_md->data.attrs, num_attrs *
4070 					sizeof(struct kfd_ioctl_svm_attribute));
4071 		set_attr[num_attrs].type = KFD_IOCTL_SVM_ATTR_CLR_FLAGS;
4072 		set_attr[num_attrs].value = ~set_flags;
4073 
4074 		ret = svm_range_set_attr(p, mm, criu_svm_md->data.start_addr,
4075 					 criu_svm_md->data.size, num_attrs + 1,
4076 					 set_attr);
4077 		if (ret) {
4078 			pr_err("CRIU: failed to set range attributes\n");
4079 			goto exit;
4080 		}
4081 
4082 		i++;
4083 	}
4084 exit:
4085 	kfree(set_attr);
4086 	list_for_each_entry_safe(criu_svm_md, next, &svms->criu_svm_metadata_list, list) {
4087 		pr_debug("freeing criu_svm_md[]\n\tstart: 0x%llx\n",
4088 						criu_svm_md->data.start_addr);
4089 		kfree(criu_svm_md);
4090 	}
4091 
4092 	mmput(mm);
4093 	return ret;
4094 
4095 }
4096 
4097 int kfd_criu_restore_svm(struct kfd_process *p,
4098 			 uint8_t __user *user_priv_ptr,
4099 			 uint64_t *priv_data_offset,
4100 			 uint64_t max_priv_data_size)
4101 {
4102 	uint64_t svm_priv_data_size, svm_object_md_size, svm_attrs_size;
4103 	int nattr_common = 4, nattr_accessibility = 1;
4104 	struct criu_svm_metadata *criu_svm_md = NULL;
4105 	struct svm_range_list *svms = &p->svms;
4106 	uint32_t num_devices;
4107 	int ret = 0;
4108 
4109 	num_devices = p->n_pdds;
4110 	/* Handle one SVM range object at a time, also the number of gpus are
4111 	 * assumed to be same on the restore node, checking must be done while
4112 	 * evaluating the topology earlier
4113 	 */
4114 
4115 	svm_attrs_size = sizeof(struct kfd_ioctl_svm_attribute) *
4116 		(nattr_common + nattr_accessibility * num_devices);
4117 	svm_object_md_size = sizeof(struct criu_svm_metadata) + svm_attrs_size;
4118 
4119 	svm_priv_data_size = sizeof(struct kfd_criu_svm_range_priv_data) +
4120 								svm_attrs_size;
4121 
4122 	criu_svm_md = kzalloc(svm_object_md_size, GFP_KERNEL);
4123 	if (!criu_svm_md) {
4124 		pr_err("failed to allocate memory to store svm metadata\n");
4125 		return -ENOMEM;
4126 	}
4127 	if (*priv_data_offset + svm_priv_data_size > max_priv_data_size) {
4128 		ret = -EINVAL;
4129 		goto exit;
4130 	}
4131 
4132 	ret = copy_from_user(&criu_svm_md->data, user_priv_ptr + *priv_data_offset,
4133 			     svm_priv_data_size);
4134 	if (ret) {
4135 		ret = -EFAULT;
4136 		goto exit;
4137 	}
4138 	*priv_data_offset += svm_priv_data_size;
4139 
4140 	list_add_tail(&criu_svm_md->list, &svms->criu_svm_metadata_list);
4141 
4142 	return 0;
4143 
4144 
4145 exit:
4146 	kfree(criu_svm_md);
4147 	return ret;
4148 }
4149 
4150 void svm_range_get_info(struct kfd_process *p, uint32_t *num_svm_ranges,
4151 			uint64_t *svm_priv_data_size)
4152 {
4153 	uint64_t total_size, accessibility_size, common_attr_size;
4154 	int nattr_common = 4, nattr_accessibility = 1;
4155 	int num_devices = p->n_pdds;
4156 	struct svm_range_list *svms;
4157 	struct svm_range *prange;
4158 	uint32_t count = 0;
4159 
4160 	*svm_priv_data_size = 0;
4161 
4162 	svms = &p->svms;
4163 
4164 	mutex_lock(&svms->lock);
4165 	list_for_each_entry(prange, &svms->list, list) {
4166 		pr_debug("prange: 0x%p start: 0x%lx\t npages: 0x%llx\t end: 0x%llx\n",
4167 			 prange, prange->start, prange->npages,
4168 			 prange->start + prange->npages - 1);
4169 		count++;
4170 	}
4171 	mutex_unlock(&svms->lock);
4172 
4173 	*num_svm_ranges = count;
4174 	/* Only the accessbility attributes need to be queried for all the gpus
4175 	 * individually, remaining ones are spanned across the entire process
4176 	 * regardless of the various gpu nodes. Of the remaining attributes,
4177 	 * KFD_IOCTL_SVM_ATTR_CLR_FLAGS need not be saved.
4178 	 *
4179 	 * KFD_IOCTL_SVM_ATTR_PREFERRED_LOC
4180 	 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC
4181 	 * KFD_IOCTL_SVM_ATTR_SET_FLAGS
4182 	 * KFD_IOCTL_SVM_ATTR_GRANULARITY
4183 	 *
4184 	 * ** ACCESSBILITY ATTRIBUTES **
4185 	 * (Considered as one, type is altered during query, value is gpuid)
4186 	 * KFD_IOCTL_SVM_ATTR_ACCESS
4187 	 * KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE
4188 	 * KFD_IOCTL_SVM_ATTR_NO_ACCESS
4189 	 */
4190 	if (*num_svm_ranges > 0) {
4191 		common_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4192 			nattr_common;
4193 		accessibility_size = sizeof(struct kfd_ioctl_svm_attribute) *
4194 			nattr_accessibility * num_devices;
4195 
4196 		total_size = sizeof(struct kfd_criu_svm_range_priv_data) +
4197 			common_attr_size + accessibility_size;
4198 
4199 		*svm_priv_data_size = *num_svm_ranges * total_size;
4200 	}
4201 
4202 	pr_debug("num_svm_ranges %u total_priv_size %llu\n", *num_svm_ranges,
4203 		 *svm_priv_data_size);
4204 }
4205 
4206 int kfd_criu_checkpoint_svm(struct kfd_process *p,
4207 			    uint8_t __user *user_priv_data,
4208 			    uint64_t *priv_data_offset)
4209 {
4210 	struct kfd_criu_svm_range_priv_data *svm_priv = NULL;
4211 	struct kfd_ioctl_svm_attribute *query_attr = NULL;
4212 	uint64_t svm_priv_data_size, query_attr_size = 0;
4213 	int index, nattr_common = 4, ret = 0;
4214 	struct svm_range_list *svms;
4215 	int num_devices = p->n_pdds;
4216 	struct svm_range *prange;
4217 	struct mm_struct *mm;
4218 
4219 	svms = &p->svms;
4220 
4221 	mm = get_task_mm(p->lead_thread);
4222 	if (!mm) {
4223 		pr_err("failed to get mm for the target process\n");
4224 		return -ESRCH;
4225 	}
4226 
4227 	query_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4228 				(nattr_common + num_devices);
4229 
4230 	query_attr = kzalloc(query_attr_size, GFP_KERNEL);
4231 	if (!query_attr) {
4232 		ret = -ENOMEM;
4233 		goto exit;
4234 	}
4235 
4236 	query_attr[0].type = KFD_IOCTL_SVM_ATTR_PREFERRED_LOC;
4237 	query_attr[1].type = KFD_IOCTL_SVM_ATTR_PREFETCH_LOC;
4238 	query_attr[2].type = KFD_IOCTL_SVM_ATTR_SET_FLAGS;
4239 	query_attr[3].type = KFD_IOCTL_SVM_ATTR_GRANULARITY;
4240 
4241 	for (index = 0; index < num_devices; index++) {
4242 		struct kfd_process_device *pdd = p->pdds[index];
4243 
4244 		query_attr[index + nattr_common].type =
4245 			KFD_IOCTL_SVM_ATTR_ACCESS;
4246 		query_attr[index + nattr_common].value = pdd->user_gpu_id;
4247 	}
4248 
4249 	svm_priv_data_size = sizeof(*svm_priv) + query_attr_size;
4250 
4251 	svm_priv = kzalloc(svm_priv_data_size, GFP_KERNEL);
4252 	if (!svm_priv) {
4253 		ret = -ENOMEM;
4254 		goto exit_query;
4255 	}
4256 
4257 	index = 0;
4258 	list_for_each_entry(prange, &svms->list, list) {
4259 
4260 		svm_priv->object_type = KFD_CRIU_OBJECT_TYPE_SVM_RANGE;
4261 		svm_priv->start_addr = prange->start;
4262 		svm_priv->size = prange->npages;
4263 		memcpy(&svm_priv->attrs, query_attr, query_attr_size);
4264 		pr_debug("CRIU: prange: 0x%p start: 0x%lx\t npages: 0x%llx end: 0x%llx\t size: 0x%llx\n",
4265 			 prange, prange->start, prange->npages,
4266 			 prange->start + prange->npages - 1,
4267 			 prange->npages * PAGE_SIZE);
4268 
4269 		ret = svm_range_get_attr(p, mm, svm_priv->start_addr,
4270 					 svm_priv->size,
4271 					 (nattr_common + num_devices),
4272 					 svm_priv->attrs);
4273 		if (ret) {
4274 			pr_err("CRIU: failed to obtain range attributes\n");
4275 			goto exit_priv;
4276 		}
4277 
4278 		if (copy_to_user(user_priv_data + *priv_data_offset, svm_priv,
4279 				 svm_priv_data_size)) {
4280 			pr_err("Failed to copy svm priv to user\n");
4281 			ret = -EFAULT;
4282 			goto exit_priv;
4283 		}
4284 
4285 		*priv_data_offset += svm_priv_data_size;
4286 
4287 	}
4288 
4289 
4290 exit_priv:
4291 	kfree(svm_priv);
4292 exit_query:
4293 	kfree(query_attr);
4294 exit:
4295 	mmput(mm);
4296 	return ret;
4297 }
4298 
4299 int
4300 svm_ioctl(struct kfd_process *p, enum kfd_ioctl_svm_op op, uint64_t start,
4301 	  uint64_t size, uint32_t nattrs, struct kfd_ioctl_svm_attribute *attrs)
4302 {
4303 	struct mm_struct *mm = current->mm;
4304 	int r;
4305 
4306 	start >>= PAGE_SHIFT;
4307 	size >>= PAGE_SHIFT;
4308 
4309 	switch (op) {
4310 	case KFD_IOCTL_SVM_OP_SET_ATTR:
4311 		r = svm_range_set_attr(p, mm, start, size, nattrs, attrs);
4312 		break;
4313 	case KFD_IOCTL_SVM_OP_GET_ATTR:
4314 		r = svm_range_get_attr(p, mm, start, size, nattrs, attrs);
4315 		break;
4316 	default:
4317 		r = -EINVAL;
4318 		break;
4319 	}
4320 
4321 	return r;
4322 }
4323