xref: /linux/drivers/gpu/drm/amd/amdkfd/kfd_svm.c (revision c909a49128a31bced8cfbd2dfb0a4fe56e01a6d0)
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 "kfd_priv.h"
37 #include "kfd_svm.h"
38 #include "kfd_migrate.h"
39 #include "kfd_smi_events.h"
40 
41 #ifdef dev_fmt
42 #undef dev_fmt
43 #endif
44 #define dev_fmt(fmt) "kfd_svm: %s: " fmt, __func__
45 
46 #define AMDGPU_SVM_RANGE_RESTORE_DELAY_MS 1
47 
48 /* Long enough to ensure no retry fault comes after svm range is restored and
49  * page table is updated.
50  */
51 #define AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING	(2UL * NSEC_PER_MSEC)
52 #if IS_ENABLED(CONFIG_DYNAMIC_DEBUG)
53 #define dynamic_svm_range_dump(svms) \
54 	_dynamic_func_call_no_desc("svm_range_dump", svm_range_debug_dump, svms)
55 #else
56 #define dynamic_svm_range_dump(svms) \
57 	do { if (0) svm_range_debug_dump(svms); } while (0)
58 #endif
59 
60 /* Giant svm range split into smaller ranges based on this, it is decided using
61  * minimum of all dGPU/APU 1/32 VRAM size, between 2MB to 1GB and alignment to
62  * power of 2MB.
63  */
64 static uint64_t max_svm_range_pages;
65 
66 struct criu_svm_metadata {
67 	struct list_head list;
68 	struct kfd_criu_svm_range_priv_data data;
69 };
70 
71 static void svm_range_evict_svm_bo_worker(struct work_struct *work);
72 static bool
73 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
74 				    const struct mmu_notifier_range *range,
75 				    unsigned long cur_seq);
76 static int
77 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
78 		   uint64_t *bo_s, uint64_t *bo_l);
79 static const struct mmu_interval_notifier_ops svm_range_mn_ops = {
80 	.invalidate = svm_range_cpu_invalidate_pagetables,
81 };
82 
83 /**
84  * svm_range_unlink - unlink svm_range from lists and interval tree
85  * @prange: svm range structure to be removed
86  *
87  * Remove the svm_range from the svms and svm_bo lists and the svms
88  * interval tree.
89  *
90  * Context: The caller must hold svms->lock
91  */
92 static void svm_range_unlink(struct svm_range *prange)
93 {
94 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
95 		 prange, prange->start, prange->last);
96 
97 	if (prange->svm_bo) {
98 		spin_lock(&prange->svm_bo->list_lock);
99 		list_del(&prange->svm_bo_list);
100 		spin_unlock(&prange->svm_bo->list_lock);
101 	}
102 
103 	list_del(&prange->list);
104 	if (prange->it_node.start != 0 && prange->it_node.last != 0)
105 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
106 }
107 
108 static void
109 svm_range_add_notifier_locked(struct mm_struct *mm, struct svm_range *prange)
110 {
111 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
112 		 prange, prange->start, prange->last);
113 
114 	mmu_interval_notifier_insert_locked(&prange->notifier, mm,
115 				     prange->start << PAGE_SHIFT,
116 				     prange->npages << PAGE_SHIFT,
117 				     &svm_range_mn_ops);
118 }
119 
120 /**
121  * svm_range_add_to_svms - add svm range to svms
122  * @prange: svm range structure to be added
123  *
124  * Add the svm range to svms interval tree and link list
125  *
126  * Context: The caller must hold svms->lock
127  */
128 static void svm_range_add_to_svms(struct svm_range *prange)
129 {
130 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
131 		 prange, prange->start, prange->last);
132 
133 	list_move_tail(&prange->list, &prange->svms->list);
134 	prange->it_node.start = prange->start;
135 	prange->it_node.last = prange->last;
136 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
137 }
138 
139 static void svm_range_remove_notifier(struct svm_range *prange)
140 {
141 	pr_debug("remove notifier svms 0x%p prange 0x%p [0x%lx 0x%lx]\n",
142 		 prange->svms, prange,
143 		 prange->notifier.interval_tree.start >> PAGE_SHIFT,
144 		 prange->notifier.interval_tree.last >> PAGE_SHIFT);
145 
146 	if (prange->notifier.interval_tree.start != 0 &&
147 	    prange->notifier.interval_tree.last != 0)
148 		mmu_interval_notifier_remove(&prange->notifier);
149 }
150 
151 static bool
152 svm_is_valid_dma_mapping_addr(struct device *dev, dma_addr_t dma_addr)
153 {
154 	return dma_addr && !dma_mapping_error(dev, dma_addr) &&
155 	       !(dma_addr & SVM_RANGE_VRAM_DOMAIN);
156 }
157 
158 static int
159 svm_range_dma_map_dev(struct amdgpu_device *adev, struct svm_range *prange,
160 		      unsigned long offset, unsigned long npages,
161 		      unsigned long *hmm_pfns, uint32_t gpuidx)
162 {
163 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
164 	dma_addr_t *addr = prange->dma_addr[gpuidx];
165 	struct device *dev = adev->dev;
166 	struct page *page;
167 	int i, r;
168 
169 	if (!addr) {
170 		addr = kvcalloc(prange->npages, sizeof(*addr), GFP_KERNEL);
171 		if (!addr)
172 			return -ENOMEM;
173 		prange->dma_addr[gpuidx] = addr;
174 	}
175 
176 	addr += offset;
177 	for (i = 0; i < npages; i++) {
178 		if (svm_is_valid_dma_mapping_addr(dev, addr[i]))
179 			dma_unmap_page(dev, addr[i], PAGE_SIZE, dir);
180 
181 		page = hmm_pfn_to_page(hmm_pfns[i]);
182 		if (is_zone_device_page(page)) {
183 			struct amdgpu_device *bo_adev = prange->svm_bo->node->adev;
184 
185 			addr[i] = (hmm_pfns[i] << PAGE_SHIFT) +
186 				   bo_adev->vm_manager.vram_base_offset -
187 				   bo_adev->kfd.pgmap.range.start;
188 			addr[i] |= SVM_RANGE_VRAM_DOMAIN;
189 			pr_debug_ratelimited("vram address: 0x%llx\n", addr[i]);
190 			continue;
191 		}
192 		addr[i] = dma_map_page(dev, page, 0, PAGE_SIZE, dir);
193 		r = dma_mapping_error(dev, addr[i]);
194 		if (r) {
195 			dev_err(dev, "failed %d dma_map_page\n", r);
196 			return r;
197 		}
198 		pr_debug_ratelimited("dma mapping 0x%llx for page addr 0x%lx\n",
199 				     addr[i] >> PAGE_SHIFT, page_to_pfn(page));
200 	}
201 
202 	return 0;
203 }
204 
205 static int
206 svm_range_dma_map(struct svm_range *prange, unsigned long *bitmap,
207 		  unsigned long offset, unsigned long npages,
208 		  unsigned long *hmm_pfns)
209 {
210 	struct kfd_process *p;
211 	uint32_t gpuidx;
212 	int r;
213 
214 	p = container_of(prange->svms, struct kfd_process, svms);
215 
216 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
217 		struct kfd_process_device *pdd;
218 
219 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
220 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
221 		if (!pdd) {
222 			pr_debug("failed to find device idx %d\n", gpuidx);
223 			return -EINVAL;
224 		}
225 
226 		r = svm_range_dma_map_dev(pdd->dev->adev, prange, offset, npages,
227 					  hmm_pfns, gpuidx);
228 		if (r)
229 			break;
230 	}
231 
232 	return r;
233 }
234 
235 void svm_range_dma_unmap_dev(struct device *dev, dma_addr_t *dma_addr,
236 			 unsigned long offset, unsigned long npages)
237 {
238 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
239 	int i;
240 
241 	if (!dma_addr)
242 		return;
243 
244 	for (i = offset; i < offset + npages; i++) {
245 		if (!svm_is_valid_dma_mapping_addr(dev, dma_addr[i]))
246 			continue;
247 		pr_debug_ratelimited("unmap 0x%llx\n", dma_addr[i] >> PAGE_SHIFT);
248 		dma_unmap_page(dev, dma_addr[i], PAGE_SIZE, dir);
249 		dma_addr[i] = 0;
250 	}
251 }
252 
253 void svm_range_dma_unmap(struct svm_range *prange)
254 {
255 	struct kfd_process_device *pdd;
256 	dma_addr_t *dma_addr;
257 	struct device *dev;
258 	struct kfd_process *p;
259 	uint32_t gpuidx;
260 
261 	p = container_of(prange->svms, struct kfd_process, svms);
262 
263 	for (gpuidx = 0; gpuidx < MAX_GPU_INSTANCE; gpuidx++) {
264 		dma_addr = prange->dma_addr[gpuidx];
265 		if (!dma_addr)
266 			continue;
267 
268 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
269 		if (!pdd) {
270 			pr_debug("failed to find device idx %d\n", gpuidx);
271 			continue;
272 		}
273 		dev = &pdd->dev->adev->pdev->dev;
274 
275 		svm_range_dma_unmap_dev(dev, dma_addr, 0, prange->npages);
276 	}
277 }
278 
279 static void svm_range_free(struct svm_range *prange, bool do_unmap)
280 {
281 	uint64_t size = (prange->last - prange->start + 1) << PAGE_SHIFT;
282 	struct kfd_process *p = container_of(prange->svms, struct kfd_process, svms);
283 	uint32_t gpuidx;
284 
285 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms, prange,
286 		 prange->start, prange->last);
287 
288 	svm_range_vram_node_free(prange);
289 	if (do_unmap)
290 		svm_range_dma_unmap(prange);
291 
292 	if (do_unmap && !p->xnack_enabled) {
293 		pr_debug("unreserve prange 0x%p size: 0x%llx\n", prange, size);
294 		amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
295 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
296 	}
297 
298 	/* free dma_addr array for each gpu */
299 	for (gpuidx = 0; gpuidx < MAX_GPU_INSTANCE; gpuidx++) {
300 		if (prange->dma_addr[gpuidx]) {
301 			kvfree(prange->dma_addr[gpuidx]);
302 			prange->dma_addr[gpuidx] = NULL;
303 		}
304 	}
305 
306 	mutex_destroy(&prange->lock);
307 	mutex_destroy(&prange->migrate_mutex);
308 	kfree(prange);
309 }
310 
311 static void
312 svm_range_set_default_attributes(struct svm_range_list *svms, int32_t *location,
313 				 int32_t *prefetch_loc, uint8_t *granularity,
314 				 uint32_t *flags)
315 {
316 	*location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
317 	*prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
318 	*granularity = svms->default_granularity;
319 	*flags =
320 		KFD_IOCTL_SVM_FLAG_HOST_ACCESS | KFD_IOCTL_SVM_FLAG_COHERENT;
321 }
322 
323 static struct
324 svm_range *svm_range_new(struct svm_range_list *svms, uint64_t start,
325 			 uint64_t last, bool update_mem_usage)
326 {
327 	uint64_t size = last - start + 1;
328 	struct svm_range *prange;
329 	struct kfd_process *p;
330 
331 	prange = kzalloc(sizeof(*prange), GFP_KERNEL);
332 	if (!prange)
333 		return NULL;
334 
335 	p = container_of(svms, struct kfd_process, svms);
336 	if (!p->xnack_enabled && update_mem_usage &&
337 	    amdgpu_amdkfd_reserve_mem_limit(NULL, size << PAGE_SHIFT,
338 				    KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0)) {
339 		pr_info("SVM mapping failed, exceeds resident system memory limit\n");
340 		kfree(prange);
341 		return NULL;
342 	}
343 	prange->npages = size;
344 	prange->svms = svms;
345 	prange->start = start;
346 	prange->last = last;
347 	INIT_LIST_HEAD(&prange->list);
348 	INIT_LIST_HEAD(&prange->update_list);
349 	INIT_LIST_HEAD(&prange->svm_bo_list);
350 	INIT_LIST_HEAD(&prange->deferred_list);
351 	INIT_LIST_HEAD(&prange->child_list);
352 	atomic_set(&prange->invalid, 0);
353 	prange->validate_timestamp = 0;
354 	prange->vram_pages = 0;
355 	mutex_init(&prange->migrate_mutex);
356 	mutex_init(&prange->lock);
357 
358 	if (p->xnack_enabled)
359 		bitmap_copy(prange->bitmap_access, svms->bitmap_supported,
360 			    MAX_GPU_INSTANCE);
361 
362 	svm_range_set_default_attributes(svms, &prange->preferred_loc,
363 					 &prange->prefetch_loc,
364 					 &prange->granularity, &prange->flags);
365 
366 	pr_debug("svms 0x%p [0x%llx 0x%llx]\n", svms, start, last);
367 
368 	return prange;
369 }
370 
371 static bool svm_bo_ref_unless_zero(struct svm_range_bo *svm_bo)
372 {
373 	if (!svm_bo || !kref_get_unless_zero(&svm_bo->kref))
374 		return false;
375 
376 	return true;
377 }
378 
379 static void svm_range_bo_release(struct kref *kref)
380 {
381 	struct svm_range_bo *svm_bo;
382 
383 	svm_bo = container_of(kref, struct svm_range_bo, kref);
384 	pr_debug("svm_bo 0x%p\n", svm_bo);
385 
386 	spin_lock(&svm_bo->list_lock);
387 	while (!list_empty(&svm_bo->range_list)) {
388 		struct svm_range *prange =
389 				list_first_entry(&svm_bo->range_list,
390 						struct svm_range, svm_bo_list);
391 		/* list_del_init tells a concurrent svm_range_vram_node_new when
392 		 * it's safe to reuse the svm_bo pointer and svm_bo_list head.
393 		 */
394 		list_del_init(&prange->svm_bo_list);
395 		spin_unlock(&svm_bo->list_lock);
396 
397 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
398 			 prange->start, prange->last);
399 		mutex_lock(&prange->lock);
400 		prange->svm_bo = NULL;
401 		/* prange should not hold vram page now */
402 		WARN_ONCE(prange->actual_loc, "prange should not hold vram page");
403 		mutex_unlock(&prange->lock);
404 
405 		spin_lock(&svm_bo->list_lock);
406 	}
407 	spin_unlock(&svm_bo->list_lock);
408 
409 	if (mmget_not_zero(svm_bo->eviction_fence->mm)) {
410 		struct kfd_process_device *pdd;
411 		struct kfd_process *p;
412 		struct mm_struct *mm;
413 
414 		mm = svm_bo->eviction_fence->mm;
415 		/*
416 		 * The forked child process takes svm_bo device pages ref, svm_bo could be
417 		 * released after parent process is gone.
418 		 */
419 		p = kfd_lookup_process_by_mm(mm);
420 		if (p) {
421 			pdd = kfd_get_process_device_data(svm_bo->node, p);
422 			if (pdd)
423 				atomic64_sub(amdgpu_bo_size(svm_bo->bo), &pdd->vram_usage);
424 			kfd_unref_process(p);
425 		}
426 		mmput(mm);
427 	}
428 
429 	if (!dma_fence_is_signaled(&svm_bo->eviction_fence->base))
430 		/* We're not in the eviction worker. Signal the fence. */
431 		dma_fence_signal(&svm_bo->eviction_fence->base);
432 	dma_fence_put(&svm_bo->eviction_fence->base);
433 	amdgpu_bo_unref(&svm_bo->bo);
434 	kfree(svm_bo);
435 }
436 
437 static void svm_range_bo_wq_release(struct work_struct *work)
438 {
439 	struct svm_range_bo *svm_bo;
440 
441 	svm_bo = container_of(work, struct svm_range_bo, release_work);
442 	svm_range_bo_release(&svm_bo->kref);
443 }
444 
445 static void svm_range_bo_release_async(struct kref *kref)
446 {
447 	struct svm_range_bo *svm_bo;
448 
449 	svm_bo = container_of(kref, struct svm_range_bo, kref);
450 	pr_debug("svm_bo 0x%p\n", svm_bo);
451 	INIT_WORK(&svm_bo->release_work, svm_range_bo_wq_release);
452 	schedule_work(&svm_bo->release_work);
453 }
454 
455 void svm_range_bo_unref_async(struct svm_range_bo *svm_bo)
456 {
457 	kref_put(&svm_bo->kref, svm_range_bo_release_async);
458 }
459 
460 static void svm_range_bo_unref(struct svm_range_bo *svm_bo)
461 {
462 	if (svm_bo)
463 		kref_put(&svm_bo->kref, svm_range_bo_release);
464 }
465 
466 static bool
467 svm_range_validate_svm_bo(struct kfd_node *node, struct svm_range *prange)
468 {
469 	mutex_lock(&prange->lock);
470 	if (!prange->svm_bo) {
471 		mutex_unlock(&prange->lock);
472 		return false;
473 	}
474 	if (prange->ttm_res) {
475 		/* We still have a reference, all is well */
476 		mutex_unlock(&prange->lock);
477 		return true;
478 	}
479 	if (svm_bo_ref_unless_zero(prange->svm_bo)) {
480 		/*
481 		 * Migrate from GPU to GPU, remove range from source svm_bo->node
482 		 * range list, and return false to allocate svm_bo from destination
483 		 * node.
484 		 */
485 		if (prange->svm_bo->node != node) {
486 			mutex_unlock(&prange->lock);
487 
488 			spin_lock(&prange->svm_bo->list_lock);
489 			list_del_init(&prange->svm_bo_list);
490 			spin_unlock(&prange->svm_bo->list_lock);
491 
492 			svm_range_bo_unref(prange->svm_bo);
493 			return false;
494 		}
495 		if (READ_ONCE(prange->svm_bo->evicting)) {
496 			struct dma_fence *f;
497 			struct svm_range_bo *svm_bo;
498 			/* The BO is getting evicted,
499 			 * we need to get a new one
500 			 */
501 			mutex_unlock(&prange->lock);
502 			svm_bo = prange->svm_bo;
503 			f = dma_fence_get(&svm_bo->eviction_fence->base);
504 			svm_range_bo_unref(prange->svm_bo);
505 			/* wait for the fence to avoid long spin-loop
506 			 * at list_empty_careful
507 			 */
508 			dma_fence_wait(f, false);
509 			dma_fence_put(f);
510 		} else {
511 			/* The BO was still around and we got
512 			 * a new reference to it
513 			 */
514 			mutex_unlock(&prange->lock);
515 			pr_debug("reuse old bo svms 0x%p [0x%lx 0x%lx]\n",
516 				 prange->svms, prange->start, prange->last);
517 
518 			prange->ttm_res = prange->svm_bo->bo->tbo.resource;
519 			return true;
520 		}
521 
522 	} else {
523 		mutex_unlock(&prange->lock);
524 	}
525 
526 	/* We need a new svm_bo. Spin-loop to wait for concurrent
527 	 * svm_range_bo_release to finish removing this range from
528 	 * its range list and set prange->svm_bo to null. After this,
529 	 * it is safe to reuse the svm_bo pointer and svm_bo_list head.
530 	 */
531 	while (!list_empty_careful(&prange->svm_bo_list) || prange->svm_bo)
532 		cond_resched();
533 
534 	return false;
535 }
536 
537 static struct svm_range_bo *svm_range_bo_new(void)
538 {
539 	struct svm_range_bo *svm_bo;
540 
541 	svm_bo = kzalloc(sizeof(*svm_bo), GFP_KERNEL);
542 	if (!svm_bo)
543 		return NULL;
544 
545 	kref_init(&svm_bo->kref);
546 	INIT_LIST_HEAD(&svm_bo->range_list);
547 	spin_lock_init(&svm_bo->list_lock);
548 
549 	return svm_bo;
550 }
551 
552 int
553 svm_range_vram_node_new(struct kfd_node *node, struct svm_range *prange,
554 			bool clear)
555 {
556 	struct kfd_process_device *pdd;
557 	struct amdgpu_bo_param bp;
558 	struct svm_range_bo *svm_bo;
559 	struct amdgpu_bo_user *ubo;
560 	struct amdgpu_bo *bo;
561 	struct kfd_process *p;
562 	struct mm_struct *mm;
563 	int r;
564 
565 	p = container_of(prange->svms, struct kfd_process, svms);
566 	pr_debug("process pid: %d svms 0x%p [0x%lx 0x%lx]\n",
567 		 p->lead_thread->pid, prange->svms,
568 		 prange->start, prange->last);
569 
570 	if (svm_range_validate_svm_bo(node, prange))
571 		return 0;
572 
573 	svm_bo = svm_range_bo_new();
574 	if (!svm_bo) {
575 		pr_debug("failed to alloc svm bo\n");
576 		return -ENOMEM;
577 	}
578 	mm = get_task_mm(p->lead_thread);
579 	if (!mm) {
580 		pr_debug("failed to get mm\n");
581 		kfree(svm_bo);
582 		return -ESRCH;
583 	}
584 	svm_bo->node = node;
585 	svm_bo->eviction_fence =
586 		amdgpu_amdkfd_fence_create(dma_fence_context_alloc(1),
587 					   mm,
588 					   svm_bo);
589 	mmput(mm);
590 	INIT_WORK(&svm_bo->eviction_work, svm_range_evict_svm_bo_worker);
591 	svm_bo->evicting = 0;
592 	memset(&bp, 0, sizeof(bp));
593 	bp.size = prange->npages * PAGE_SIZE;
594 	bp.byte_align = PAGE_SIZE;
595 	bp.domain = AMDGPU_GEM_DOMAIN_VRAM;
596 	bp.flags = AMDGPU_GEM_CREATE_NO_CPU_ACCESS;
597 	bp.flags |= clear ? AMDGPU_GEM_CREATE_VRAM_CLEARED : 0;
598 	bp.flags |= AMDGPU_GEM_CREATE_DISCARDABLE;
599 	bp.type = ttm_bo_type_device;
600 	bp.resv = NULL;
601 	if (node->xcp)
602 		bp.xcp_id_plus1 = node->xcp->id + 1;
603 
604 	r = amdgpu_bo_create_user(node->adev, &bp, &ubo);
605 	if (r) {
606 		pr_debug("failed %d to create bo\n", r);
607 		goto create_bo_failed;
608 	}
609 	bo = &ubo->bo;
610 
611 	pr_debug("alloc bo at offset 0x%lx size 0x%lx on partition %d\n",
612 		 bo->tbo.resource->start << PAGE_SHIFT, bp.size,
613 		 bp.xcp_id_plus1 - 1);
614 
615 	r = amdgpu_bo_reserve(bo, true);
616 	if (r) {
617 		pr_debug("failed %d to reserve bo\n", r);
618 		goto reserve_bo_failed;
619 	}
620 
621 	if (clear) {
622 		r = amdgpu_bo_sync_wait(bo, AMDGPU_FENCE_OWNER_KFD, false);
623 		if (r) {
624 			pr_debug("failed %d to sync bo\n", r);
625 			amdgpu_bo_unreserve(bo);
626 			goto reserve_bo_failed;
627 		}
628 	}
629 
630 	r = dma_resv_reserve_fences(bo->tbo.base.resv, 1);
631 	if (r) {
632 		pr_debug("failed %d to reserve bo\n", r);
633 		amdgpu_bo_unreserve(bo);
634 		goto reserve_bo_failed;
635 	}
636 	amdgpu_bo_fence(bo, &svm_bo->eviction_fence->base, true);
637 
638 	amdgpu_bo_unreserve(bo);
639 
640 	svm_bo->bo = bo;
641 	prange->svm_bo = svm_bo;
642 	prange->ttm_res = bo->tbo.resource;
643 	prange->offset = 0;
644 
645 	spin_lock(&svm_bo->list_lock);
646 	list_add(&prange->svm_bo_list, &svm_bo->range_list);
647 	spin_unlock(&svm_bo->list_lock);
648 
649 	pdd = svm_range_get_pdd_by_node(prange, node);
650 	if (pdd)
651 		atomic64_add(amdgpu_bo_size(bo), &pdd->vram_usage);
652 
653 	return 0;
654 
655 reserve_bo_failed:
656 	amdgpu_bo_unref(&bo);
657 create_bo_failed:
658 	dma_fence_put(&svm_bo->eviction_fence->base);
659 	kfree(svm_bo);
660 	prange->ttm_res = NULL;
661 
662 	return r;
663 }
664 
665 void svm_range_vram_node_free(struct svm_range *prange)
666 {
667 	/* serialize prange->svm_bo unref */
668 	mutex_lock(&prange->lock);
669 	/* prange->svm_bo has not been unref */
670 	if (prange->ttm_res) {
671 		prange->ttm_res = NULL;
672 		mutex_unlock(&prange->lock);
673 		svm_range_bo_unref(prange->svm_bo);
674 	} else
675 		mutex_unlock(&prange->lock);
676 }
677 
678 struct kfd_node *
679 svm_range_get_node_by_id(struct svm_range *prange, uint32_t gpu_id)
680 {
681 	struct kfd_process *p;
682 	struct kfd_process_device *pdd;
683 
684 	p = container_of(prange->svms, struct kfd_process, svms);
685 	pdd = kfd_process_device_data_by_id(p, gpu_id);
686 	if (!pdd) {
687 		pr_debug("failed to get kfd process device by id 0x%x\n", gpu_id);
688 		return NULL;
689 	}
690 
691 	return pdd->dev;
692 }
693 
694 struct kfd_process_device *
695 svm_range_get_pdd_by_node(struct svm_range *prange, struct kfd_node *node)
696 {
697 	struct kfd_process *p;
698 
699 	p = container_of(prange->svms, struct kfd_process, svms);
700 
701 	return kfd_get_process_device_data(node, p);
702 }
703 
704 static int svm_range_bo_validate(void *param, struct amdgpu_bo *bo)
705 {
706 	struct ttm_operation_ctx ctx = { false, false };
707 
708 	amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_VRAM);
709 
710 	return ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
711 }
712 
713 static int
714 svm_range_check_attr(struct kfd_process *p,
715 		     uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
716 {
717 	uint32_t i;
718 
719 	for (i = 0; i < nattr; i++) {
720 		uint32_t val = attrs[i].value;
721 		int gpuidx = MAX_GPU_INSTANCE;
722 
723 		switch (attrs[i].type) {
724 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
725 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM &&
726 			    val != KFD_IOCTL_SVM_LOCATION_UNDEFINED)
727 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
728 			break;
729 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
730 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM)
731 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
732 			break;
733 		case KFD_IOCTL_SVM_ATTR_ACCESS:
734 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
735 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
736 			gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
737 			break;
738 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
739 			break;
740 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
741 			break;
742 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
743 			break;
744 		default:
745 			pr_debug("unknown attr type 0x%x\n", attrs[i].type);
746 			return -EINVAL;
747 		}
748 
749 		if (gpuidx < 0) {
750 			pr_debug("no GPU 0x%x found\n", val);
751 			return -EINVAL;
752 		} else if (gpuidx < MAX_GPU_INSTANCE &&
753 			   !test_bit(gpuidx, p->svms.bitmap_supported)) {
754 			pr_debug("GPU 0x%x not supported\n", val);
755 			return -EINVAL;
756 		}
757 	}
758 
759 	return 0;
760 }
761 
762 static void
763 svm_range_apply_attrs(struct kfd_process *p, struct svm_range *prange,
764 		      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
765 		      bool *update_mapping)
766 {
767 	uint32_t i;
768 	int gpuidx;
769 
770 	for (i = 0; i < nattr; i++) {
771 		switch (attrs[i].type) {
772 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
773 			prange->preferred_loc = attrs[i].value;
774 			break;
775 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
776 			prange->prefetch_loc = attrs[i].value;
777 			break;
778 		case KFD_IOCTL_SVM_ATTR_ACCESS:
779 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
780 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
781 			if (!p->xnack_enabled)
782 				*update_mapping = true;
783 
784 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
785 							       attrs[i].value);
786 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
787 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
788 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
789 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
790 				bitmap_set(prange->bitmap_access, gpuidx, 1);
791 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
792 			} else {
793 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
794 				bitmap_set(prange->bitmap_aip, gpuidx, 1);
795 			}
796 			break;
797 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
798 			*update_mapping = true;
799 			prange->flags |= attrs[i].value;
800 			break;
801 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
802 			*update_mapping = true;
803 			prange->flags &= ~attrs[i].value;
804 			break;
805 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
806 			prange->granularity = min_t(uint32_t, attrs[i].value, 0x3F);
807 			break;
808 		default:
809 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
810 		}
811 	}
812 }
813 
814 static bool
815 svm_range_is_same_attrs(struct kfd_process *p, struct svm_range *prange,
816 			uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
817 {
818 	uint32_t i;
819 	int gpuidx;
820 
821 	for (i = 0; i < nattr; i++) {
822 		switch (attrs[i].type) {
823 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
824 			if (prange->preferred_loc != attrs[i].value)
825 				return false;
826 			break;
827 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
828 			/* Prefetch should always trigger a migration even
829 			 * if the value of the attribute didn't change.
830 			 */
831 			return false;
832 		case KFD_IOCTL_SVM_ATTR_ACCESS:
833 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
834 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
835 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
836 							       attrs[i].value);
837 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
838 				if (test_bit(gpuidx, prange->bitmap_access) ||
839 				    test_bit(gpuidx, prange->bitmap_aip))
840 					return false;
841 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
842 				if (!test_bit(gpuidx, prange->bitmap_access))
843 					return false;
844 			} else {
845 				if (!test_bit(gpuidx, prange->bitmap_aip))
846 					return false;
847 			}
848 			break;
849 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
850 			if ((prange->flags & attrs[i].value) != attrs[i].value)
851 				return false;
852 			break;
853 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
854 			if ((prange->flags & attrs[i].value) != 0)
855 				return false;
856 			break;
857 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
858 			if (prange->granularity != attrs[i].value)
859 				return false;
860 			break;
861 		default:
862 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
863 		}
864 	}
865 
866 	return true;
867 }
868 
869 /**
870  * svm_range_debug_dump - print all range information from svms
871  * @svms: svm range list header
872  *
873  * debug output svm range start, end, prefetch location from svms
874  * interval tree and link list
875  *
876  * Context: The caller must hold svms->lock
877  */
878 static void svm_range_debug_dump(struct svm_range_list *svms)
879 {
880 	struct interval_tree_node *node;
881 	struct svm_range *prange;
882 
883 	pr_debug("dump svms 0x%p list\n", svms);
884 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
885 
886 	list_for_each_entry(prange, &svms->list, list) {
887 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
888 			 prange, prange->start, prange->npages,
889 			 prange->start + prange->npages - 1,
890 			 prange->actual_loc);
891 	}
892 
893 	pr_debug("dump svms 0x%p interval tree\n", svms);
894 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
895 	node = interval_tree_iter_first(&svms->objects, 0, ~0ULL);
896 	while (node) {
897 		prange = container_of(node, struct svm_range, it_node);
898 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
899 			 prange, prange->start, prange->npages,
900 			 prange->start + prange->npages - 1,
901 			 prange->actual_loc);
902 		node = interval_tree_iter_next(node, 0, ~0ULL);
903 	}
904 }
905 
906 static void *
907 svm_range_copy_array(void *psrc, size_t size, uint64_t num_elements,
908 		     uint64_t offset, uint64_t *vram_pages)
909 {
910 	unsigned char *src = (unsigned char *)psrc + offset;
911 	unsigned char *dst;
912 	uint64_t i;
913 
914 	dst = kvmalloc_array(num_elements, size, GFP_KERNEL);
915 	if (!dst)
916 		return NULL;
917 
918 	if (!vram_pages) {
919 		memcpy(dst, src, num_elements * size);
920 		return (void *)dst;
921 	}
922 
923 	*vram_pages = 0;
924 	for (i = 0; i < num_elements; i++) {
925 		dma_addr_t *temp;
926 		temp = (dma_addr_t *)dst + i;
927 		*temp = *((dma_addr_t *)src + i);
928 		if (*temp&SVM_RANGE_VRAM_DOMAIN)
929 			(*vram_pages)++;
930 	}
931 
932 	return (void *)dst;
933 }
934 
935 static int
936 svm_range_copy_dma_addrs(struct svm_range *dst, struct svm_range *src)
937 {
938 	int i;
939 
940 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
941 		if (!src->dma_addr[i])
942 			continue;
943 		dst->dma_addr[i] = svm_range_copy_array(src->dma_addr[i],
944 					sizeof(*src->dma_addr[i]), src->npages, 0, NULL);
945 		if (!dst->dma_addr[i])
946 			return -ENOMEM;
947 	}
948 
949 	return 0;
950 }
951 
952 static int
953 svm_range_split_array(void *ppnew, void *ppold, size_t size,
954 		      uint64_t old_start, uint64_t old_n,
955 		      uint64_t new_start, uint64_t new_n, uint64_t *new_vram_pages)
956 {
957 	unsigned char *new, *old, *pold;
958 	uint64_t d;
959 
960 	if (!ppold)
961 		return 0;
962 	pold = *(unsigned char **)ppold;
963 	if (!pold)
964 		return 0;
965 
966 	d = (new_start - old_start) * size;
967 	/* get dma addr array for new range and calculte its vram page number */
968 	new = svm_range_copy_array(pold, size, new_n, d, new_vram_pages);
969 	if (!new)
970 		return -ENOMEM;
971 	d = (new_start == old_start) ? new_n * size : 0;
972 	old = svm_range_copy_array(pold, size, old_n, d, NULL);
973 	if (!old) {
974 		kvfree(new);
975 		return -ENOMEM;
976 	}
977 	kvfree(pold);
978 	*(void **)ppold = old;
979 	*(void **)ppnew = new;
980 
981 	return 0;
982 }
983 
984 static int
985 svm_range_split_pages(struct svm_range *new, struct svm_range *old,
986 		      uint64_t start, uint64_t last)
987 {
988 	uint64_t npages = last - start + 1;
989 	int i, r;
990 
991 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
992 		r = svm_range_split_array(&new->dma_addr[i], &old->dma_addr[i],
993 					  sizeof(*old->dma_addr[i]), old->start,
994 					  npages, new->start, new->npages,
995 					  old->actual_loc ? &new->vram_pages : NULL);
996 		if (r)
997 			return r;
998 	}
999 	if (old->actual_loc)
1000 		old->vram_pages -= new->vram_pages;
1001 
1002 	return 0;
1003 }
1004 
1005 static int
1006 svm_range_split_nodes(struct svm_range *new, struct svm_range *old,
1007 		      uint64_t start, uint64_t last)
1008 {
1009 	uint64_t npages = last - start + 1;
1010 
1011 	pr_debug("svms 0x%p new prange 0x%p start 0x%lx [0x%llx 0x%llx]\n",
1012 		 new->svms, new, new->start, start, last);
1013 
1014 	if (new->start == old->start) {
1015 		new->offset = old->offset;
1016 		old->offset += new->npages;
1017 	} else {
1018 		new->offset = old->offset + npages;
1019 	}
1020 
1021 	new->svm_bo = svm_range_bo_ref(old->svm_bo);
1022 	new->ttm_res = old->ttm_res;
1023 
1024 	spin_lock(&new->svm_bo->list_lock);
1025 	list_add(&new->svm_bo_list, &new->svm_bo->range_list);
1026 	spin_unlock(&new->svm_bo->list_lock);
1027 
1028 	return 0;
1029 }
1030 
1031 /**
1032  * svm_range_split_adjust - split range and adjust
1033  *
1034  * @new: new range
1035  * @old: the old range
1036  * @start: the old range adjust to start address in pages
1037  * @last: the old range adjust to last address in pages
1038  *
1039  * Copy system memory dma_addr or vram ttm_res in old range to new
1040  * range from new_start up to size new->npages, the remaining old range is from
1041  * start to last
1042  *
1043  * Return:
1044  * 0 - OK, -ENOMEM - out of memory
1045  */
1046 static int
1047 svm_range_split_adjust(struct svm_range *new, struct svm_range *old,
1048 		      uint64_t start, uint64_t last)
1049 {
1050 	int r;
1051 
1052 	pr_debug("svms 0x%p new 0x%lx old [0x%lx 0x%lx] => [0x%llx 0x%llx]\n",
1053 		 new->svms, new->start, old->start, old->last, start, last);
1054 
1055 	if (new->start < old->start ||
1056 	    new->last > old->last) {
1057 		WARN_ONCE(1, "invalid new range start or last\n");
1058 		return -EINVAL;
1059 	}
1060 
1061 	r = svm_range_split_pages(new, old, start, last);
1062 	if (r)
1063 		return r;
1064 
1065 	if (old->actual_loc && old->ttm_res) {
1066 		r = svm_range_split_nodes(new, old, start, last);
1067 		if (r)
1068 			return r;
1069 	}
1070 
1071 	old->npages = last - start + 1;
1072 	old->start = start;
1073 	old->last = last;
1074 	new->flags = old->flags;
1075 	new->preferred_loc = old->preferred_loc;
1076 	new->prefetch_loc = old->prefetch_loc;
1077 	new->actual_loc = old->actual_loc;
1078 	new->granularity = old->granularity;
1079 	new->mapped_to_gpu = old->mapped_to_gpu;
1080 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
1081 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
1082 	atomic_set(&new->queue_refcount, atomic_read(&old->queue_refcount));
1083 
1084 	return 0;
1085 }
1086 
1087 /**
1088  * svm_range_split - split a range in 2 ranges
1089  *
1090  * @prange: the svm range to split
1091  * @start: the remaining range start address in pages
1092  * @last: the remaining range last address in pages
1093  * @new: the result new range generated
1094  *
1095  * Two cases only:
1096  * case 1: if start == prange->start
1097  *         prange ==> prange[start, last]
1098  *         new range [last + 1, prange->last]
1099  *
1100  * case 2: if last == prange->last
1101  *         prange ==> prange[start, last]
1102  *         new range [prange->start, start - 1]
1103  *
1104  * Return:
1105  * 0 - OK, -ENOMEM - out of memory, -EINVAL - invalid start, last
1106  */
1107 static int
1108 svm_range_split(struct svm_range *prange, uint64_t start, uint64_t last,
1109 		struct svm_range **new)
1110 {
1111 	uint64_t old_start = prange->start;
1112 	uint64_t old_last = prange->last;
1113 	struct svm_range_list *svms;
1114 	int r = 0;
1115 
1116 	pr_debug("svms 0x%p [0x%llx 0x%llx] to [0x%llx 0x%llx]\n", prange->svms,
1117 		 old_start, old_last, start, last);
1118 
1119 	if (old_start != start && old_last != last)
1120 		return -EINVAL;
1121 	if (start < old_start || last > old_last)
1122 		return -EINVAL;
1123 
1124 	svms = prange->svms;
1125 	if (old_start == start)
1126 		*new = svm_range_new(svms, last + 1, old_last, false);
1127 	else
1128 		*new = svm_range_new(svms, old_start, start - 1, false);
1129 	if (!*new)
1130 		return -ENOMEM;
1131 
1132 	r = svm_range_split_adjust(*new, prange, start, last);
1133 	if (r) {
1134 		pr_debug("failed %d split [0x%llx 0x%llx] to [0x%llx 0x%llx]\n",
1135 			 r, old_start, old_last, start, last);
1136 		svm_range_free(*new, false);
1137 		*new = NULL;
1138 	}
1139 
1140 	return r;
1141 }
1142 
1143 static int
1144 svm_range_split_tail(struct svm_range *prange, uint64_t new_last,
1145 		     struct list_head *insert_list, struct list_head *remap_list)
1146 {
1147 	struct svm_range *tail = NULL;
1148 	int r = svm_range_split(prange, prange->start, new_last, &tail);
1149 
1150 	if (!r) {
1151 		list_add(&tail->list, insert_list);
1152 		if (!IS_ALIGNED(new_last + 1, 1UL << prange->granularity))
1153 			list_add(&tail->update_list, remap_list);
1154 	}
1155 	return r;
1156 }
1157 
1158 static int
1159 svm_range_split_head(struct svm_range *prange, uint64_t new_start,
1160 		     struct list_head *insert_list, struct list_head *remap_list)
1161 {
1162 	struct svm_range *head = NULL;
1163 	int r = svm_range_split(prange, new_start, prange->last, &head);
1164 
1165 	if (!r) {
1166 		list_add(&head->list, insert_list);
1167 		if (!IS_ALIGNED(new_start, 1UL << prange->granularity))
1168 			list_add(&head->update_list, remap_list);
1169 	}
1170 	return r;
1171 }
1172 
1173 static void
1174 svm_range_add_child(struct svm_range *prange, struct mm_struct *mm,
1175 		    struct svm_range *pchild, enum svm_work_list_ops op)
1176 {
1177 	pr_debug("add child 0x%p [0x%lx 0x%lx] to prange 0x%p child list %d\n",
1178 		 pchild, pchild->start, pchild->last, prange, op);
1179 
1180 	pchild->work_item.mm = mm;
1181 	pchild->work_item.op = op;
1182 	list_add_tail(&pchild->child_list, &prange->child_list);
1183 }
1184 
1185 static bool
1186 svm_nodes_in_same_hive(struct kfd_node *node_a, struct kfd_node *node_b)
1187 {
1188 	return (node_a->adev == node_b->adev ||
1189 		amdgpu_xgmi_same_hive(node_a->adev, node_b->adev));
1190 }
1191 
1192 static uint64_t
1193 svm_range_get_pte_flags(struct kfd_node *node,
1194 			struct svm_range *prange, int domain)
1195 {
1196 	struct kfd_node *bo_node;
1197 	uint32_t flags = prange->flags;
1198 	uint32_t mapping_flags = 0;
1199 	uint32_t gc_ip_version = KFD_GC_VERSION(node);
1200 	uint64_t pte_flags;
1201 	bool snoop = (domain != SVM_RANGE_VRAM_DOMAIN);
1202 	bool coherent = flags & (KFD_IOCTL_SVM_FLAG_COHERENT | KFD_IOCTL_SVM_FLAG_EXT_COHERENT);
1203 	bool ext_coherent = flags & KFD_IOCTL_SVM_FLAG_EXT_COHERENT;
1204 	unsigned int mtype_local;
1205 
1206 	if (domain == SVM_RANGE_VRAM_DOMAIN)
1207 		bo_node = prange->svm_bo->node;
1208 
1209 	switch (gc_ip_version) {
1210 	case IP_VERSION(9, 4, 1):
1211 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1212 			if (bo_node == node) {
1213 				mapping_flags |= coherent ?
1214 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1215 			} else {
1216 				mapping_flags |= coherent ?
1217 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1218 				if (svm_nodes_in_same_hive(node, bo_node))
1219 					snoop = true;
1220 			}
1221 		} else {
1222 			mapping_flags |= coherent ?
1223 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1224 		}
1225 		break;
1226 	case IP_VERSION(9, 4, 2):
1227 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1228 			if (bo_node == node) {
1229 				mapping_flags |= coherent ?
1230 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1231 				if (node->adev->gmc.xgmi.connected_to_cpu)
1232 					snoop = true;
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, 3):
1245 	case IP_VERSION(9, 4, 4):
1246 	case IP_VERSION(9, 5, 0):
1247 		if (ext_coherent)
1248 			mtype_local = (gc_ip_version < IP_VERSION(9, 5, 0) && !node->adev->rev_id) ?
1249 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_CC;
1250 		else
1251 			mtype_local = amdgpu_mtype_local == 1 ? AMDGPU_VM_MTYPE_NC :
1252 				amdgpu_mtype_local == 2 ? AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1253 		snoop = true;
1254 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1255 			/* local HBM region close to partition */
1256 			if (bo_node->adev == node->adev &&
1257 			    (!bo_node->xcp || !node->xcp || bo_node->xcp->mem_id == node->xcp->mem_id))
1258 				mapping_flags |= mtype_local;
1259 			/* local HBM region far from partition or remote XGMI GPU
1260 			 * with regular system scope coherence
1261 			 */
1262 			else if (svm_nodes_in_same_hive(bo_node, node) && !ext_coherent)
1263 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1264 			/* PCIe P2P on GPUs pre-9.5.0 */
1265 			else if (gc_ip_version < IP_VERSION(9, 5, 0) &&
1266 				 !svm_nodes_in_same_hive(bo_node, node))
1267 				mapping_flags |= AMDGPU_VM_MTYPE_UC;
1268 			/* Other remote memory */
1269 			else
1270 				mapping_flags |= ext_coherent ? AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1271 		/* system memory accessed by the APU */
1272 		} else if (node->adev->flags & AMD_IS_APU) {
1273 			/* On NUMA systems, locality is determined per-page
1274 			 * in amdgpu_gmc_override_vm_pte_flags
1275 			 */
1276 			if (num_possible_nodes() <= 1)
1277 				mapping_flags |= mtype_local;
1278 			else
1279 				mapping_flags |= ext_coherent ? AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1280 		/* system memory accessed by the dGPU */
1281 		} else {
1282 			if (gc_ip_version < IP_VERSION(9, 5, 0))
1283 				mapping_flags |= AMDGPU_VM_MTYPE_UC;
1284 			else
1285 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1286 		}
1287 		break;
1288 	case IP_VERSION(12, 0, 0):
1289 	case IP_VERSION(12, 0, 1):
1290 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1291 			if (bo_node != node)
1292 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1293 		} else {
1294 			mapping_flags |= coherent ?
1295 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1296 		}
1297 		break;
1298 	default:
1299 		mapping_flags |= coherent ?
1300 			AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1301 	}
1302 
1303 	mapping_flags |= AMDGPU_VM_PAGE_READABLE | AMDGPU_VM_PAGE_WRITEABLE;
1304 
1305 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_RO)
1306 		mapping_flags &= ~AMDGPU_VM_PAGE_WRITEABLE;
1307 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_EXEC)
1308 		mapping_flags |= AMDGPU_VM_PAGE_EXECUTABLE;
1309 
1310 	pte_flags = AMDGPU_PTE_VALID;
1311 	pte_flags |= (domain == SVM_RANGE_VRAM_DOMAIN) ? 0 : AMDGPU_PTE_SYSTEM;
1312 	pte_flags |= snoop ? AMDGPU_PTE_SNOOPED : 0;
1313 	if (gc_ip_version >= IP_VERSION(12, 0, 0))
1314 		pte_flags |= AMDGPU_PTE_IS_PTE;
1315 
1316 	pte_flags |= amdgpu_gem_va_map_flags(node->adev, mapping_flags);
1317 	return pte_flags;
1318 }
1319 
1320 static int
1321 svm_range_unmap_from_gpu(struct amdgpu_device *adev, struct amdgpu_vm *vm,
1322 			 uint64_t start, uint64_t last,
1323 			 struct dma_fence **fence)
1324 {
1325 	uint64_t init_pte_value = 0;
1326 
1327 	pr_debug("[0x%llx 0x%llx]\n", start, last);
1328 
1329 	return amdgpu_vm_update_range(adev, vm, false, true, true, false, NULL, start,
1330 				      last, init_pte_value, 0, 0, NULL, NULL,
1331 				      fence);
1332 }
1333 
1334 static int
1335 svm_range_unmap_from_gpus(struct svm_range *prange, unsigned long start,
1336 			  unsigned long last, uint32_t trigger)
1337 {
1338 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1339 	struct kfd_process_device *pdd;
1340 	struct dma_fence *fence = NULL;
1341 	struct kfd_process *p;
1342 	uint32_t gpuidx;
1343 	int r = 0;
1344 
1345 	if (!prange->mapped_to_gpu) {
1346 		pr_debug("prange 0x%p [0x%lx 0x%lx] not mapped to GPU\n",
1347 			 prange, prange->start, prange->last);
1348 		return 0;
1349 	}
1350 
1351 	if (prange->start == start && prange->last == last) {
1352 		pr_debug("unmap svms 0x%p prange 0x%p\n", prange->svms, prange);
1353 		prange->mapped_to_gpu = false;
1354 	}
1355 
1356 	bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
1357 		  MAX_GPU_INSTANCE);
1358 	p = container_of(prange->svms, struct kfd_process, svms);
1359 
1360 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1361 		pr_debug("unmap from gpu idx 0x%x\n", gpuidx);
1362 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1363 		if (!pdd) {
1364 			pr_debug("failed to find device idx %d\n", gpuidx);
1365 			return -EINVAL;
1366 		}
1367 
1368 		kfd_smi_event_unmap_from_gpu(pdd->dev, p->lead_thread->pid,
1369 					     start, last, trigger);
1370 
1371 		r = svm_range_unmap_from_gpu(pdd->dev->adev,
1372 					     drm_priv_to_vm(pdd->drm_priv),
1373 					     start, last, &fence);
1374 		if (r)
1375 			break;
1376 
1377 		if (fence) {
1378 			r = dma_fence_wait(fence, false);
1379 			dma_fence_put(fence);
1380 			fence = NULL;
1381 			if (r)
1382 				break;
1383 		}
1384 		kfd_flush_tlb(pdd, TLB_FLUSH_HEAVYWEIGHT);
1385 	}
1386 
1387 	return r;
1388 }
1389 
1390 static int
1391 svm_range_map_to_gpu(struct kfd_process_device *pdd, struct svm_range *prange,
1392 		     unsigned long offset, unsigned long npages, bool readonly,
1393 		     dma_addr_t *dma_addr, struct amdgpu_device *bo_adev,
1394 		     struct dma_fence **fence, bool flush_tlb)
1395 {
1396 	struct amdgpu_device *adev = pdd->dev->adev;
1397 	struct amdgpu_vm *vm = drm_priv_to_vm(pdd->drm_priv);
1398 	uint64_t pte_flags;
1399 	unsigned long last_start;
1400 	int last_domain;
1401 	int r = 0;
1402 	int64_t i, j;
1403 
1404 	last_start = prange->start + offset;
1405 
1406 	pr_debug("svms 0x%p [0x%lx 0x%lx] readonly %d\n", prange->svms,
1407 		 last_start, last_start + npages - 1, readonly);
1408 
1409 	for (i = offset; i < offset + npages; i++) {
1410 		last_domain = dma_addr[i] & SVM_RANGE_VRAM_DOMAIN;
1411 		dma_addr[i] &= ~SVM_RANGE_VRAM_DOMAIN;
1412 
1413 		/* Collect all pages in the same address range and memory domain
1414 		 * that can be mapped with a single call to update mapping.
1415 		 */
1416 		if (i < offset + npages - 1 &&
1417 		    last_domain == (dma_addr[i + 1] & SVM_RANGE_VRAM_DOMAIN))
1418 			continue;
1419 
1420 		pr_debug("Mapping range [0x%lx 0x%llx] on domain: %s\n",
1421 			 last_start, prange->start + i, last_domain ? "GPU" : "CPU");
1422 
1423 		pte_flags = svm_range_get_pte_flags(pdd->dev, prange, last_domain);
1424 		if (readonly)
1425 			pte_flags &= ~AMDGPU_PTE_WRITEABLE;
1426 
1427 		pr_debug("svms 0x%p map [0x%lx 0x%llx] vram %d PTE 0x%llx\n",
1428 			 prange->svms, last_start, prange->start + i,
1429 			 (last_domain == SVM_RANGE_VRAM_DOMAIN) ? 1 : 0,
1430 			 pte_flags);
1431 
1432 		/* For dGPU mode, we use same vm_manager to allocate VRAM for
1433 		 * different memory partition based on fpfn/lpfn, we should use
1434 		 * same vm_manager.vram_base_offset regardless memory partition.
1435 		 */
1436 		r = amdgpu_vm_update_range(adev, vm, false, false, flush_tlb, true,
1437 					   NULL, last_start, prange->start + i,
1438 					   pte_flags,
1439 					   (last_start - prange->start) << PAGE_SHIFT,
1440 					   bo_adev ? bo_adev->vm_manager.vram_base_offset : 0,
1441 					   NULL, dma_addr, &vm->last_update);
1442 
1443 		for (j = last_start - prange->start; j <= i; j++)
1444 			dma_addr[j] |= last_domain;
1445 
1446 		if (r) {
1447 			pr_debug("failed %d to map to gpu 0x%lx\n", r, prange->start);
1448 			goto out;
1449 		}
1450 		last_start = prange->start + i + 1;
1451 	}
1452 
1453 	r = amdgpu_vm_update_pdes(adev, vm, false);
1454 	if (r) {
1455 		pr_debug("failed %d to update directories 0x%lx\n", r,
1456 			 prange->start);
1457 		goto out;
1458 	}
1459 
1460 	if (fence)
1461 		*fence = dma_fence_get(vm->last_update);
1462 
1463 out:
1464 	return r;
1465 }
1466 
1467 static int
1468 svm_range_map_to_gpus(struct svm_range *prange, unsigned long offset,
1469 		      unsigned long npages, bool readonly,
1470 		      unsigned long *bitmap, bool wait, bool flush_tlb)
1471 {
1472 	struct kfd_process_device *pdd;
1473 	struct amdgpu_device *bo_adev = NULL;
1474 	struct kfd_process *p;
1475 	struct dma_fence *fence = NULL;
1476 	uint32_t gpuidx;
1477 	int r = 0;
1478 
1479 	if (prange->svm_bo && prange->ttm_res)
1480 		bo_adev = prange->svm_bo->node->adev;
1481 
1482 	p = container_of(prange->svms, struct kfd_process, svms);
1483 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1484 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
1485 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1486 		if (!pdd) {
1487 			pr_debug("failed to find device idx %d\n", gpuidx);
1488 			return -EINVAL;
1489 		}
1490 
1491 		pdd = kfd_bind_process_to_device(pdd->dev, p);
1492 		if (IS_ERR(pdd))
1493 			return -EINVAL;
1494 
1495 		if (bo_adev && pdd->dev->adev != bo_adev &&
1496 		    !amdgpu_xgmi_same_hive(pdd->dev->adev, bo_adev)) {
1497 			pr_debug("cannot map to device idx %d\n", gpuidx);
1498 			continue;
1499 		}
1500 
1501 		r = svm_range_map_to_gpu(pdd, prange, offset, npages, readonly,
1502 					 prange->dma_addr[gpuidx],
1503 					 bo_adev, wait ? &fence : NULL,
1504 					 flush_tlb);
1505 		if (r)
1506 			break;
1507 
1508 		if (fence) {
1509 			r = dma_fence_wait(fence, false);
1510 			dma_fence_put(fence);
1511 			fence = NULL;
1512 			if (r) {
1513 				pr_debug("failed %d to dma fence wait\n", r);
1514 				break;
1515 			}
1516 		}
1517 
1518 		kfd_flush_tlb(pdd, TLB_FLUSH_LEGACY);
1519 	}
1520 
1521 	return r;
1522 }
1523 
1524 struct svm_validate_context {
1525 	struct kfd_process *process;
1526 	struct svm_range *prange;
1527 	bool intr;
1528 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1529 	struct drm_exec exec;
1530 };
1531 
1532 static int svm_range_reserve_bos(struct svm_validate_context *ctx, bool intr)
1533 {
1534 	struct kfd_process_device *pdd;
1535 	struct amdgpu_vm *vm;
1536 	uint32_t gpuidx;
1537 	int r;
1538 
1539 	drm_exec_init(&ctx->exec, intr ? DRM_EXEC_INTERRUPTIBLE_WAIT: 0, 0);
1540 	drm_exec_until_all_locked(&ctx->exec) {
1541 		for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1542 			pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1543 			if (!pdd) {
1544 				pr_debug("failed to find device idx %d\n", gpuidx);
1545 				r = -EINVAL;
1546 				goto unreserve_out;
1547 			}
1548 			vm = drm_priv_to_vm(pdd->drm_priv);
1549 
1550 			r = amdgpu_vm_lock_pd(vm, &ctx->exec, 2);
1551 			drm_exec_retry_on_contention(&ctx->exec);
1552 			if (unlikely(r)) {
1553 				pr_debug("failed %d to reserve bo\n", r);
1554 				goto unreserve_out;
1555 			}
1556 		}
1557 	}
1558 
1559 	for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1560 		pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1561 		if (!pdd) {
1562 			pr_debug("failed to find device idx %d\n", gpuidx);
1563 			r = -EINVAL;
1564 			goto unreserve_out;
1565 		}
1566 
1567 		r = amdgpu_vm_validate(pdd->dev->adev,
1568 				       drm_priv_to_vm(pdd->drm_priv), NULL,
1569 				       svm_range_bo_validate, NULL);
1570 		if (r) {
1571 			pr_debug("failed %d validate pt bos\n", r);
1572 			goto unreserve_out;
1573 		}
1574 	}
1575 
1576 	return 0;
1577 
1578 unreserve_out:
1579 	drm_exec_fini(&ctx->exec);
1580 	return r;
1581 }
1582 
1583 static void svm_range_unreserve_bos(struct svm_validate_context *ctx)
1584 {
1585 	drm_exec_fini(&ctx->exec);
1586 }
1587 
1588 static void *kfd_svm_page_owner(struct kfd_process *p, int32_t gpuidx)
1589 {
1590 	struct kfd_process_device *pdd;
1591 
1592 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1593 	if (!pdd)
1594 		return NULL;
1595 
1596 	return SVM_ADEV_PGMAP_OWNER(pdd->dev->adev);
1597 }
1598 
1599 /*
1600  * Validation+GPU mapping with concurrent invalidation (MMU notifiers)
1601  *
1602  * To prevent concurrent destruction or change of range attributes, the
1603  * svm_read_lock must be held. The caller must not hold the svm_write_lock
1604  * because that would block concurrent evictions and lead to deadlocks. To
1605  * serialize concurrent migrations or validations of the same range, the
1606  * prange->migrate_mutex must be held.
1607  *
1608  * For VRAM ranges, the SVM BO must be allocated and valid (protected by its
1609  * eviction fence.
1610  *
1611  * The following sequence ensures race-free validation and GPU mapping:
1612  *
1613  * 1. Reserve page table (and SVM BO if range is in VRAM)
1614  * 2. hmm_range_fault to get page addresses (if system memory)
1615  * 3. DMA-map pages (if system memory)
1616  * 4-a. Take notifier lock
1617  * 4-b. Check that pages still valid (mmu_interval_read_retry)
1618  * 4-c. Check that the range was not split or otherwise invalidated
1619  * 4-d. Update GPU page table
1620  * 4.e. Release notifier lock
1621  * 5. Release page table (and SVM BO) reservation
1622  */
1623 static int svm_range_validate_and_map(struct mm_struct *mm,
1624 				      unsigned long map_start, unsigned long map_last,
1625 				      struct svm_range *prange, int32_t gpuidx,
1626 				      bool intr, bool wait, bool flush_tlb)
1627 {
1628 	struct svm_validate_context *ctx;
1629 	unsigned long start, end, addr;
1630 	struct kfd_process *p;
1631 	void *owner;
1632 	int32_t idx;
1633 	int r = 0;
1634 
1635 	ctx = kzalloc(sizeof(struct svm_validate_context), GFP_KERNEL);
1636 	if (!ctx)
1637 		return -ENOMEM;
1638 	ctx->process = container_of(prange->svms, struct kfd_process, svms);
1639 	ctx->prange = prange;
1640 	ctx->intr = intr;
1641 
1642 	if (gpuidx < MAX_GPU_INSTANCE) {
1643 		bitmap_zero(ctx->bitmap, MAX_GPU_INSTANCE);
1644 		bitmap_set(ctx->bitmap, gpuidx, 1);
1645 	} else if (ctx->process->xnack_enabled) {
1646 		bitmap_copy(ctx->bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
1647 
1648 		/* If prefetch range to GPU, or GPU retry fault migrate range to
1649 		 * GPU, which has ACCESS attribute to the range, create mapping
1650 		 * on that GPU.
1651 		 */
1652 		if (prange->actual_loc) {
1653 			gpuidx = kfd_process_gpuidx_from_gpuid(ctx->process,
1654 							prange->actual_loc);
1655 			if (gpuidx < 0) {
1656 				WARN_ONCE(1, "failed get device by id 0x%x\n",
1657 					 prange->actual_loc);
1658 				r = -EINVAL;
1659 				goto free_ctx;
1660 			}
1661 			if (test_bit(gpuidx, prange->bitmap_access))
1662 				bitmap_set(ctx->bitmap, gpuidx, 1);
1663 		}
1664 
1665 		/*
1666 		 * If prange is already mapped or with always mapped flag,
1667 		 * update mapping on GPUs with ACCESS attribute
1668 		 */
1669 		if (bitmap_empty(ctx->bitmap, MAX_GPU_INSTANCE)) {
1670 			if (prange->mapped_to_gpu ||
1671 			    prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)
1672 				bitmap_copy(ctx->bitmap, prange->bitmap_access, MAX_GPU_INSTANCE);
1673 		}
1674 	} else {
1675 		bitmap_or(ctx->bitmap, prange->bitmap_access,
1676 			  prange->bitmap_aip, MAX_GPU_INSTANCE);
1677 	}
1678 
1679 	if (bitmap_empty(ctx->bitmap, MAX_GPU_INSTANCE)) {
1680 		r = 0;
1681 		goto free_ctx;
1682 	}
1683 
1684 	if (prange->actual_loc && !prange->ttm_res) {
1685 		/* This should never happen. actual_loc gets set by
1686 		 * svm_migrate_ram_to_vram after allocating a BO.
1687 		 */
1688 		WARN_ONCE(1, "VRAM BO missing during validation\n");
1689 		r = -EINVAL;
1690 		goto free_ctx;
1691 	}
1692 
1693 	r = svm_range_reserve_bos(ctx, intr);
1694 	if (r)
1695 		goto free_ctx;
1696 
1697 	p = container_of(prange->svms, struct kfd_process, svms);
1698 	owner = kfd_svm_page_owner(p, find_first_bit(ctx->bitmap,
1699 						MAX_GPU_INSTANCE));
1700 	for_each_set_bit(idx, ctx->bitmap, MAX_GPU_INSTANCE) {
1701 		if (kfd_svm_page_owner(p, idx) != owner) {
1702 			owner = NULL;
1703 			break;
1704 		}
1705 	}
1706 
1707 	start = map_start << PAGE_SHIFT;
1708 	end = (map_last + 1) << PAGE_SHIFT;
1709 	for (addr = start; !r && addr < end; ) {
1710 		struct hmm_range *hmm_range = NULL;
1711 		unsigned long map_start_vma;
1712 		unsigned long map_last_vma;
1713 		struct vm_area_struct *vma;
1714 		unsigned long next = 0;
1715 		unsigned long offset;
1716 		unsigned long npages;
1717 		bool readonly;
1718 
1719 		vma = vma_lookup(mm, addr);
1720 		if (vma) {
1721 			readonly = !(vma->vm_flags & VM_WRITE);
1722 
1723 			next = min(vma->vm_end, end);
1724 			npages = (next - addr) >> PAGE_SHIFT;
1725 			WRITE_ONCE(p->svms.faulting_task, current);
1726 			r = amdgpu_hmm_range_get_pages(&prange->notifier, addr, npages,
1727 						       readonly, owner, NULL,
1728 						       &hmm_range);
1729 			WRITE_ONCE(p->svms.faulting_task, NULL);
1730 			if (r)
1731 				pr_debug("failed %d to get svm range pages\n", r);
1732 		} else {
1733 			r = -EFAULT;
1734 		}
1735 
1736 		if (!r) {
1737 			offset = (addr >> PAGE_SHIFT) - prange->start;
1738 			r = svm_range_dma_map(prange, ctx->bitmap, offset, npages,
1739 					      hmm_range->hmm_pfns);
1740 			if (r)
1741 				pr_debug("failed %d to dma map range\n", r);
1742 		}
1743 
1744 		svm_range_lock(prange);
1745 
1746 		/* Free backing memory of hmm_range if it was initialized
1747 		 * Overrride return value to TRY AGAIN only if prior returns
1748 		 * were successful
1749 		 */
1750 		if (hmm_range && amdgpu_hmm_range_get_pages_done(hmm_range) && !r) {
1751 			pr_debug("hmm update the range, need validate again\n");
1752 			r = -EAGAIN;
1753 		}
1754 
1755 		if (!r && !list_empty(&prange->child_list)) {
1756 			pr_debug("range split by unmap in parallel, validate again\n");
1757 			r = -EAGAIN;
1758 		}
1759 
1760 		if (!r) {
1761 			map_start_vma = max(map_start, prange->start + offset);
1762 			map_last_vma = min(map_last, prange->start + offset + npages - 1);
1763 			if (map_start_vma <= map_last_vma) {
1764 				offset = map_start_vma - prange->start;
1765 				npages = map_last_vma - map_start_vma + 1;
1766 				r = svm_range_map_to_gpus(prange, offset, npages, readonly,
1767 							  ctx->bitmap, wait, flush_tlb);
1768 			}
1769 		}
1770 
1771 		if (!r && next == end)
1772 			prange->mapped_to_gpu = true;
1773 
1774 		svm_range_unlock(prange);
1775 
1776 		addr = next;
1777 	}
1778 
1779 	svm_range_unreserve_bos(ctx);
1780 	if (!r)
1781 		prange->validate_timestamp = ktime_get_boottime();
1782 
1783 free_ctx:
1784 	kfree(ctx);
1785 
1786 	return r;
1787 }
1788 
1789 /**
1790  * svm_range_list_lock_and_flush_work - flush pending deferred work
1791  *
1792  * @svms: the svm range list
1793  * @mm: the mm structure
1794  *
1795  * Context: Returns with mmap write lock held, pending deferred work flushed
1796  *
1797  */
1798 void
1799 svm_range_list_lock_and_flush_work(struct svm_range_list *svms,
1800 				   struct mm_struct *mm)
1801 {
1802 retry_flush_work:
1803 	flush_work(&svms->deferred_list_work);
1804 	mmap_write_lock(mm);
1805 
1806 	if (list_empty(&svms->deferred_range_list))
1807 		return;
1808 	mmap_write_unlock(mm);
1809 	pr_debug("retry flush\n");
1810 	goto retry_flush_work;
1811 }
1812 
1813 static void svm_range_restore_work(struct work_struct *work)
1814 {
1815 	struct delayed_work *dwork = to_delayed_work(work);
1816 	struct amdkfd_process_info *process_info;
1817 	struct svm_range_list *svms;
1818 	struct svm_range *prange;
1819 	struct kfd_process *p;
1820 	struct mm_struct *mm;
1821 	int evicted_ranges;
1822 	int invalid;
1823 	int r;
1824 
1825 	svms = container_of(dwork, struct svm_range_list, restore_work);
1826 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1827 	if (!evicted_ranges)
1828 		return;
1829 
1830 	pr_debug("restore svm ranges\n");
1831 
1832 	p = container_of(svms, struct kfd_process, svms);
1833 	process_info = p->kgd_process_info;
1834 
1835 	/* Keep mm reference when svm_range_validate_and_map ranges */
1836 	mm = get_task_mm(p->lead_thread);
1837 	if (!mm) {
1838 		pr_debug("svms 0x%p process mm gone\n", svms);
1839 		return;
1840 	}
1841 
1842 	mutex_lock(&process_info->lock);
1843 	svm_range_list_lock_and_flush_work(svms, mm);
1844 	mutex_lock(&svms->lock);
1845 
1846 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1847 
1848 	list_for_each_entry(prange, &svms->list, list) {
1849 		invalid = atomic_read(&prange->invalid);
1850 		if (!invalid)
1851 			continue;
1852 
1853 		pr_debug("restoring svms 0x%p prange 0x%p [0x%lx %lx] inv %d\n",
1854 			 prange->svms, prange, prange->start, prange->last,
1855 			 invalid);
1856 
1857 		/*
1858 		 * If range is migrating, wait for migration is done.
1859 		 */
1860 		mutex_lock(&prange->migrate_mutex);
1861 
1862 		r = svm_range_validate_and_map(mm, prange->start, prange->last, prange,
1863 					       MAX_GPU_INSTANCE, false, true, false);
1864 		if (r)
1865 			pr_debug("failed %d to map 0x%lx to gpus\n", r,
1866 				 prange->start);
1867 
1868 		mutex_unlock(&prange->migrate_mutex);
1869 		if (r)
1870 			goto out_reschedule;
1871 
1872 		if (atomic_cmpxchg(&prange->invalid, invalid, 0) != invalid)
1873 			goto out_reschedule;
1874 	}
1875 
1876 	if (atomic_cmpxchg(&svms->evicted_ranges, evicted_ranges, 0) !=
1877 	    evicted_ranges)
1878 		goto out_reschedule;
1879 
1880 	evicted_ranges = 0;
1881 
1882 	r = kgd2kfd_resume_mm(mm);
1883 	if (r) {
1884 		/* No recovery from this failure. Probably the CP is
1885 		 * hanging. No point trying again.
1886 		 */
1887 		pr_debug("failed %d to resume KFD\n", r);
1888 	}
1889 
1890 	pr_debug("restore svm ranges successfully\n");
1891 
1892 out_reschedule:
1893 	mutex_unlock(&svms->lock);
1894 	mmap_write_unlock(mm);
1895 	mutex_unlock(&process_info->lock);
1896 
1897 	/* If validation failed, reschedule another attempt */
1898 	if (evicted_ranges) {
1899 		pr_debug("reschedule to restore svm range\n");
1900 		queue_delayed_work(system_freezable_wq, &svms->restore_work,
1901 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1902 
1903 		kfd_smi_event_queue_restore_rescheduled(mm);
1904 	}
1905 	mmput(mm);
1906 }
1907 
1908 /**
1909  * svm_range_evict - evict svm range
1910  * @prange: svm range structure
1911  * @mm: current process mm_struct
1912  * @start: starting process queue number
1913  * @last: last process queue number
1914  * @event: mmu notifier event when range is evicted or migrated
1915  *
1916  * Stop all queues of the process to ensure GPU doesn't access the memory, then
1917  * return to let CPU evict the buffer and proceed CPU pagetable update.
1918  *
1919  * Don't need use lock to sync cpu pagetable invalidation with GPU execution.
1920  * If invalidation happens while restore work is running, restore work will
1921  * restart to ensure to get the latest CPU pages mapping to GPU, then start
1922  * the queues.
1923  */
1924 static int
1925 svm_range_evict(struct svm_range *prange, struct mm_struct *mm,
1926 		unsigned long start, unsigned long last,
1927 		enum mmu_notifier_event event)
1928 {
1929 	struct svm_range_list *svms = prange->svms;
1930 	struct svm_range *pchild;
1931 	struct kfd_process *p;
1932 	int r = 0;
1933 
1934 	p = container_of(svms, struct kfd_process, svms);
1935 
1936 	pr_debug("invalidate svms 0x%p prange [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
1937 		 svms, prange->start, prange->last, start, last);
1938 
1939 	if (!p->xnack_enabled ||
1940 	    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) {
1941 		int evicted_ranges;
1942 		bool mapped = prange->mapped_to_gpu;
1943 
1944 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1945 			if (!pchild->mapped_to_gpu)
1946 				continue;
1947 			mapped = true;
1948 			mutex_lock_nested(&pchild->lock, 1);
1949 			if (pchild->start <= last && pchild->last >= start) {
1950 				pr_debug("increment pchild invalid [0x%lx 0x%lx]\n",
1951 					 pchild->start, pchild->last);
1952 				atomic_inc(&pchild->invalid);
1953 			}
1954 			mutex_unlock(&pchild->lock);
1955 		}
1956 
1957 		if (!mapped)
1958 			return r;
1959 
1960 		if (prange->start <= last && prange->last >= start)
1961 			atomic_inc(&prange->invalid);
1962 
1963 		evicted_ranges = atomic_inc_return(&svms->evicted_ranges);
1964 		if (evicted_ranges != 1)
1965 			return r;
1966 
1967 		pr_debug("evicting svms 0x%p range [0x%lx 0x%lx]\n",
1968 			 prange->svms, prange->start, prange->last);
1969 
1970 		/* First eviction, stop the queues */
1971 		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_SVM);
1972 		if (r)
1973 			pr_debug("failed to quiesce KFD\n");
1974 
1975 		pr_debug("schedule to restore svm %p ranges\n", svms);
1976 		queue_delayed_work(system_freezable_wq, &svms->restore_work,
1977 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1978 	} else {
1979 		unsigned long s, l;
1980 		uint32_t trigger;
1981 
1982 		if (event == MMU_NOTIFY_MIGRATE)
1983 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY_MIGRATE;
1984 		else
1985 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY;
1986 
1987 		pr_debug("invalidate unmap svms 0x%p [0x%lx 0x%lx] from GPUs\n",
1988 			 prange->svms, start, last);
1989 		list_for_each_entry(pchild, &prange->child_list, child_list) {
1990 			mutex_lock_nested(&pchild->lock, 1);
1991 			s = max(start, pchild->start);
1992 			l = min(last, pchild->last);
1993 			if (l >= s)
1994 				svm_range_unmap_from_gpus(pchild, s, l, trigger);
1995 			mutex_unlock(&pchild->lock);
1996 		}
1997 		s = max(start, prange->start);
1998 		l = min(last, prange->last);
1999 		if (l >= s)
2000 			svm_range_unmap_from_gpus(prange, s, l, trigger);
2001 	}
2002 
2003 	return r;
2004 }
2005 
2006 static struct svm_range *svm_range_clone(struct svm_range *old)
2007 {
2008 	struct svm_range *new;
2009 
2010 	new = svm_range_new(old->svms, old->start, old->last, false);
2011 	if (!new)
2012 		return NULL;
2013 	if (svm_range_copy_dma_addrs(new, old)) {
2014 		svm_range_free(new, false);
2015 		return NULL;
2016 	}
2017 	if (old->svm_bo) {
2018 		new->ttm_res = old->ttm_res;
2019 		new->offset = old->offset;
2020 		new->svm_bo = svm_range_bo_ref(old->svm_bo);
2021 		spin_lock(&new->svm_bo->list_lock);
2022 		list_add(&new->svm_bo_list, &new->svm_bo->range_list);
2023 		spin_unlock(&new->svm_bo->list_lock);
2024 	}
2025 	new->flags = old->flags;
2026 	new->preferred_loc = old->preferred_loc;
2027 	new->prefetch_loc = old->prefetch_loc;
2028 	new->actual_loc = old->actual_loc;
2029 	new->granularity = old->granularity;
2030 	new->mapped_to_gpu = old->mapped_to_gpu;
2031 	new->vram_pages = old->vram_pages;
2032 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
2033 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
2034 	atomic_set(&new->queue_refcount, atomic_read(&old->queue_refcount));
2035 
2036 	return new;
2037 }
2038 
2039 void svm_range_set_max_pages(struct amdgpu_device *adev)
2040 {
2041 	uint64_t max_pages;
2042 	uint64_t pages, _pages;
2043 	uint64_t min_pages = 0;
2044 	int i, id;
2045 
2046 	for (i = 0; i < adev->kfd.dev->num_nodes; i++) {
2047 		if (adev->kfd.dev->nodes[i]->xcp)
2048 			id = adev->kfd.dev->nodes[i]->xcp->id;
2049 		else
2050 			id = -1;
2051 		pages = KFD_XCP_MEMORY_SIZE(adev, id) >> 17;
2052 		pages = clamp(pages, 1ULL << 9, 1ULL << 18);
2053 		pages = rounddown_pow_of_two(pages);
2054 		min_pages = min_not_zero(min_pages, pages);
2055 	}
2056 
2057 	do {
2058 		max_pages = READ_ONCE(max_svm_range_pages);
2059 		_pages = min_not_zero(max_pages, min_pages);
2060 	} while (cmpxchg(&max_svm_range_pages, max_pages, _pages) != max_pages);
2061 }
2062 
2063 static int
2064 svm_range_split_new(struct svm_range_list *svms, uint64_t start, uint64_t last,
2065 		    uint64_t max_pages, struct list_head *insert_list,
2066 		    struct list_head *update_list)
2067 {
2068 	struct svm_range *prange;
2069 	uint64_t l;
2070 
2071 	pr_debug("max_svm_range_pages 0x%llx adding [0x%llx 0x%llx]\n",
2072 		 max_pages, start, last);
2073 
2074 	while (last >= start) {
2075 		l = min(last, ALIGN_DOWN(start + max_pages, max_pages) - 1);
2076 
2077 		prange = svm_range_new(svms, start, l, true);
2078 		if (!prange)
2079 			return -ENOMEM;
2080 		list_add(&prange->list, insert_list);
2081 		list_add(&prange->update_list, update_list);
2082 
2083 		start = l + 1;
2084 	}
2085 	return 0;
2086 }
2087 
2088 /**
2089  * svm_range_add - add svm range and handle overlap
2090  * @p: the range add to this process svms
2091  * @start: page size aligned
2092  * @size: page size aligned
2093  * @nattr: number of attributes
2094  * @attrs: array of attributes
2095  * @update_list: output, the ranges need validate and update GPU mapping
2096  * @insert_list: output, the ranges need insert to svms
2097  * @remove_list: output, the ranges are replaced and need remove from svms
2098  * @remap_list: output, remap unaligned svm ranges
2099  *
2100  * Check if the virtual address range has overlap with any existing ranges,
2101  * split partly overlapping ranges and add new ranges in the gaps. All changes
2102  * should be applied to the range_list and interval tree transactionally. If
2103  * any range split or allocation fails, the entire update fails. Therefore any
2104  * existing overlapping svm_ranges are cloned and the original svm_ranges left
2105  * unchanged.
2106  *
2107  * If the transaction succeeds, the caller can update and insert clones and
2108  * new ranges, then free the originals.
2109  *
2110  * Otherwise the caller can free the clones and new ranges, while the old
2111  * svm_ranges remain unchanged.
2112  *
2113  * Context: Process context, caller must hold svms->lock
2114  *
2115  * Return:
2116  * 0 - OK, otherwise error code
2117  */
2118 static int
2119 svm_range_add(struct kfd_process *p, uint64_t start, uint64_t size,
2120 	      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
2121 	      struct list_head *update_list, struct list_head *insert_list,
2122 	      struct list_head *remove_list, struct list_head *remap_list)
2123 {
2124 	unsigned long last = start + size - 1UL;
2125 	struct svm_range_list *svms = &p->svms;
2126 	struct interval_tree_node *node;
2127 	struct svm_range *prange;
2128 	struct svm_range *tmp;
2129 	struct list_head new_list;
2130 	int r = 0;
2131 
2132 	pr_debug("svms 0x%p [0x%llx 0x%lx]\n", &p->svms, start, last);
2133 
2134 	INIT_LIST_HEAD(update_list);
2135 	INIT_LIST_HEAD(insert_list);
2136 	INIT_LIST_HEAD(remove_list);
2137 	INIT_LIST_HEAD(&new_list);
2138 	INIT_LIST_HEAD(remap_list);
2139 
2140 	node = interval_tree_iter_first(&svms->objects, start, last);
2141 	while (node) {
2142 		struct interval_tree_node *next;
2143 		unsigned long next_start;
2144 
2145 		pr_debug("found overlap node [0x%lx 0x%lx]\n", node->start,
2146 			 node->last);
2147 
2148 		prange = container_of(node, struct svm_range, it_node);
2149 		next = interval_tree_iter_next(node, start, last);
2150 		next_start = min(node->last, last) + 1;
2151 
2152 		if (svm_range_is_same_attrs(p, prange, nattr, attrs) &&
2153 		    prange->mapped_to_gpu) {
2154 			/* nothing to do */
2155 		} else if (node->start < start || node->last > last) {
2156 			/* node intersects the update range and its attributes
2157 			 * will change. Clone and split it, apply updates only
2158 			 * to the overlapping part
2159 			 */
2160 			struct svm_range *old = prange;
2161 
2162 			prange = svm_range_clone(old);
2163 			if (!prange) {
2164 				r = -ENOMEM;
2165 				goto out;
2166 			}
2167 
2168 			list_add(&old->update_list, remove_list);
2169 			list_add(&prange->list, insert_list);
2170 			list_add(&prange->update_list, update_list);
2171 
2172 			if (node->start < start) {
2173 				pr_debug("change old range start\n");
2174 				r = svm_range_split_head(prange, start,
2175 							 insert_list, remap_list);
2176 				if (r)
2177 					goto out;
2178 			}
2179 			if (node->last > last) {
2180 				pr_debug("change old range last\n");
2181 				r = svm_range_split_tail(prange, last,
2182 							 insert_list, remap_list);
2183 				if (r)
2184 					goto out;
2185 			}
2186 		} else {
2187 			/* The node is contained within start..last,
2188 			 * just update it
2189 			 */
2190 			list_add(&prange->update_list, update_list);
2191 		}
2192 
2193 		/* insert a new node if needed */
2194 		if (node->start > start) {
2195 			r = svm_range_split_new(svms, start, node->start - 1,
2196 						READ_ONCE(max_svm_range_pages),
2197 						&new_list, update_list);
2198 			if (r)
2199 				goto out;
2200 		}
2201 
2202 		node = next;
2203 		start = next_start;
2204 	}
2205 
2206 	/* add a final range at the end if needed */
2207 	if (start <= last)
2208 		r = svm_range_split_new(svms, start, last,
2209 					READ_ONCE(max_svm_range_pages),
2210 					&new_list, update_list);
2211 
2212 out:
2213 	if (r) {
2214 		list_for_each_entry_safe(prange, tmp, insert_list, list)
2215 			svm_range_free(prange, false);
2216 		list_for_each_entry_safe(prange, tmp, &new_list, list)
2217 			svm_range_free(prange, true);
2218 	} else {
2219 		list_splice(&new_list, insert_list);
2220 	}
2221 
2222 	return r;
2223 }
2224 
2225 static void
2226 svm_range_update_notifier_and_interval_tree(struct mm_struct *mm,
2227 					    struct svm_range *prange)
2228 {
2229 	unsigned long start;
2230 	unsigned long last;
2231 
2232 	start = prange->notifier.interval_tree.start >> PAGE_SHIFT;
2233 	last = prange->notifier.interval_tree.last >> PAGE_SHIFT;
2234 
2235 	if (prange->start == start && prange->last == last)
2236 		return;
2237 
2238 	pr_debug("up notifier 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
2239 		  prange->svms, prange, start, last, prange->start,
2240 		  prange->last);
2241 
2242 	if (start != 0 && last != 0) {
2243 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
2244 		svm_range_remove_notifier(prange);
2245 	}
2246 	prange->it_node.start = prange->start;
2247 	prange->it_node.last = prange->last;
2248 
2249 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
2250 	svm_range_add_notifier_locked(mm, prange);
2251 }
2252 
2253 static void
2254 svm_range_handle_list_op(struct svm_range_list *svms, struct svm_range *prange,
2255 			 struct mm_struct *mm)
2256 {
2257 	switch (prange->work_item.op) {
2258 	case SVM_OP_NULL:
2259 		pr_debug("NULL OP 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2260 			 svms, prange, prange->start, prange->last);
2261 		break;
2262 	case SVM_OP_UNMAP_RANGE:
2263 		pr_debug("remove 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2264 			 svms, prange, prange->start, prange->last);
2265 		svm_range_unlink(prange);
2266 		svm_range_remove_notifier(prange);
2267 		svm_range_free(prange, true);
2268 		break;
2269 	case SVM_OP_UPDATE_RANGE_NOTIFIER:
2270 		pr_debug("update notifier 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2271 			 svms, prange, prange->start, prange->last);
2272 		svm_range_update_notifier_and_interval_tree(mm, prange);
2273 		break;
2274 	case SVM_OP_UPDATE_RANGE_NOTIFIER_AND_MAP:
2275 		pr_debug("update and map 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2276 			 svms, prange, prange->start, prange->last);
2277 		svm_range_update_notifier_and_interval_tree(mm, prange);
2278 		/* TODO: implement deferred validation and mapping */
2279 		break;
2280 	case SVM_OP_ADD_RANGE:
2281 		pr_debug("add 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms, prange,
2282 			 prange->start, prange->last);
2283 		svm_range_add_to_svms(prange);
2284 		svm_range_add_notifier_locked(mm, prange);
2285 		break;
2286 	case SVM_OP_ADD_RANGE_AND_MAP:
2287 		pr_debug("add and map 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms,
2288 			 prange, prange->start, prange->last);
2289 		svm_range_add_to_svms(prange);
2290 		svm_range_add_notifier_locked(mm, prange);
2291 		/* TODO: implement deferred validation and mapping */
2292 		break;
2293 	default:
2294 		WARN_ONCE(1, "Unknown prange 0x%p work op %d\n", prange,
2295 			 prange->work_item.op);
2296 	}
2297 }
2298 
2299 static void svm_range_drain_retry_fault(struct svm_range_list *svms)
2300 {
2301 	struct kfd_process_device *pdd;
2302 	struct kfd_process *p;
2303 	uint32_t i;
2304 
2305 	p = container_of(svms, struct kfd_process, svms);
2306 
2307 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2308 		pdd = p->pdds[i];
2309 		if (!pdd)
2310 			continue;
2311 
2312 		pr_debug("drain retry fault gpu %d svms %p\n", i, svms);
2313 
2314 		amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2315 				pdd->dev->adev->irq.retry_cam_enabled ?
2316 				&pdd->dev->adev->irq.ih :
2317 				&pdd->dev->adev->irq.ih1);
2318 
2319 		if (pdd->dev->adev->irq.retry_cam_enabled)
2320 			amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2321 				&pdd->dev->adev->irq.ih_soft);
2322 
2323 
2324 		pr_debug("drain retry fault gpu %d svms 0x%p done\n", i, svms);
2325 	}
2326 }
2327 
2328 static void svm_range_deferred_list_work(struct work_struct *work)
2329 {
2330 	struct svm_range_list *svms;
2331 	struct svm_range *prange;
2332 	struct mm_struct *mm;
2333 
2334 	svms = container_of(work, struct svm_range_list, deferred_list_work);
2335 	pr_debug("enter svms 0x%p\n", svms);
2336 
2337 	spin_lock(&svms->deferred_list_lock);
2338 	while (!list_empty(&svms->deferred_range_list)) {
2339 		prange = list_first_entry(&svms->deferred_range_list,
2340 					  struct svm_range, deferred_list);
2341 		spin_unlock(&svms->deferred_list_lock);
2342 
2343 		pr_debug("prange 0x%p [0x%lx 0x%lx] op %d\n", prange,
2344 			 prange->start, prange->last, prange->work_item.op);
2345 
2346 		mm = prange->work_item.mm;
2347 
2348 		mmap_write_lock(mm);
2349 
2350 		/* Remove from deferred_list must be inside mmap write lock, for
2351 		 * two race cases:
2352 		 * 1. unmap_from_cpu may change work_item.op and add the range
2353 		 *    to deferred_list again, cause use after free bug.
2354 		 * 2. svm_range_list_lock_and_flush_work may hold mmap write
2355 		 *    lock and continue because deferred_list is empty, but
2356 		 *    deferred_list work is actually waiting for mmap lock.
2357 		 */
2358 		spin_lock(&svms->deferred_list_lock);
2359 		list_del_init(&prange->deferred_list);
2360 		spin_unlock(&svms->deferred_list_lock);
2361 
2362 		mutex_lock(&svms->lock);
2363 		mutex_lock(&prange->migrate_mutex);
2364 		while (!list_empty(&prange->child_list)) {
2365 			struct svm_range *pchild;
2366 
2367 			pchild = list_first_entry(&prange->child_list,
2368 						struct svm_range, child_list);
2369 			pr_debug("child prange 0x%p op %d\n", pchild,
2370 				 pchild->work_item.op);
2371 			list_del_init(&pchild->child_list);
2372 			svm_range_handle_list_op(svms, pchild, mm);
2373 		}
2374 		mutex_unlock(&prange->migrate_mutex);
2375 
2376 		svm_range_handle_list_op(svms, prange, mm);
2377 		mutex_unlock(&svms->lock);
2378 		mmap_write_unlock(mm);
2379 
2380 		/* Pairs with mmget in svm_range_add_list_work. If dropping the
2381 		 * last mm refcount, schedule release work to avoid circular locking
2382 		 */
2383 		mmput_async(mm);
2384 
2385 		spin_lock(&svms->deferred_list_lock);
2386 	}
2387 	spin_unlock(&svms->deferred_list_lock);
2388 	pr_debug("exit svms 0x%p\n", svms);
2389 }
2390 
2391 void
2392 svm_range_add_list_work(struct svm_range_list *svms, struct svm_range *prange,
2393 			struct mm_struct *mm, enum svm_work_list_ops op)
2394 {
2395 	spin_lock(&svms->deferred_list_lock);
2396 	/* if prange is on the deferred list */
2397 	if (!list_empty(&prange->deferred_list)) {
2398 		pr_debug("update exist prange 0x%p work op %d\n", prange, op);
2399 		WARN_ONCE(prange->work_item.mm != mm, "unmatch mm\n");
2400 		if (op != SVM_OP_NULL &&
2401 		    prange->work_item.op != SVM_OP_UNMAP_RANGE)
2402 			prange->work_item.op = op;
2403 	} else {
2404 		prange->work_item.op = op;
2405 
2406 		/* Pairs with mmput in deferred_list_work */
2407 		mmget(mm);
2408 		prange->work_item.mm = mm;
2409 		list_add_tail(&prange->deferred_list,
2410 			      &prange->svms->deferred_range_list);
2411 		pr_debug("add prange 0x%p [0x%lx 0x%lx] to work list op %d\n",
2412 			 prange, prange->start, prange->last, op);
2413 	}
2414 	spin_unlock(&svms->deferred_list_lock);
2415 }
2416 
2417 void schedule_deferred_list_work(struct svm_range_list *svms)
2418 {
2419 	spin_lock(&svms->deferred_list_lock);
2420 	if (!list_empty(&svms->deferred_range_list))
2421 		schedule_work(&svms->deferred_list_work);
2422 	spin_unlock(&svms->deferred_list_lock);
2423 }
2424 
2425 static void
2426 svm_range_unmap_split(struct mm_struct *mm, struct svm_range *parent,
2427 		      struct svm_range *prange, unsigned long start,
2428 		      unsigned long last)
2429 {
2430 	struct svm_range *head;
2431 	struct svm_range *tail;
2432 
2433 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2434 		pr_debug("prange 0x%p [0x%lx 0x%lx] is already freed\n", prange,
2435 			 prange->start, prange->last);
2436 		return;
2437 	}
2438 	if (start > prange->last || last < prange->start)
2439 		return;
2440 
2441 	head = tail = prange;
2442 	if (start > prange->start)
2443 		svm_range_split(prange, prange->start, start - 1, &tail);
2444 	if (last < tail->last)
2445 		svm_range_split(tail, last + 1, tail->last, &head);
2446 
2447 	if (head != prange && tail != prange) {
2448 		svm_range_add_child(parent, mm, head, SVM_OP_UNMAP_RANGE);
2449 		svm_range_add_child(parent, mm, tail, SVM_OP_ADD_RANGE);
2450 	} else if (tail != prange) {
2451 		svm_range_add_child(parent, mm, tail, SVM_OP_UNMAP_RANGE);
2452 	} else if (head != prange) {
2453 		svm_range_add_child(parent, mm, head, SVM_OP_UNMAP_RANGE);
2454 	} else if (parent != prange) {
2455 		prange->work_item.op = SVM_OP_UNMAP_RANGE;
2456 	}
2457 }
2458 
2459 static void
2460 svm_range_unmap_from_cpu(struct mm_struct *mm, struct svm_range *prange,
2461 			 unsigned long start, unsigned long last)
2462 {
2463 	uint32_t trigger = KFD_SVM_UNMAP_TRIGGER_UNMAP_FROM_CPU;
2464 	struct svm_range_list *svms;
2465 	struct svm_range *pchild;
2466 	struct kfd_process *p;
2467 	unsigned long s, l;
2468 	bool unmap_parent;
2469 	uint32_t i;
2470 
2471 	if (atomic_read(&prange->queue_refcount)) {
2472 		int r;
2473 
2474 		pr_warn("Freeing queue vital buffer 0x%lx, queue evicted\n",
2475 			prange->start << PAGE_SHIFT);
2476 		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_SVM);
2477 		if (r)
2478 			pr_debug("failed %d to quiesce KFD queues\n", r);
2479 	}
2480 
2481 	p = kfd_lookup_process_by_mm(mm);
2482 	if (!p)
2483 		return;
2484 	svms = &p->svms;
2485 
2486 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n", svms,
2487 		 prange, prange->start, prange->last, start, last);
2488 
2489 	/* calculate time stamps that are used to decide which page faults need be
2490 	 * dropped or handled before unmap pages from gpu vm
2491 	 */
2492 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2493 		struct kfd_process_device *pdd;
2494 		struct amdgpu_device *adev;
2495 		struct amdgpu_ih_ring *ih;
2496 		uint32_t checkpoint_wptr;
2497 
2498 		pdd = p->pdds[i];
2499 		if (!pdd)
2500 			continue;
2501 
2502 		adev = pdd->dev->adev;
2503 
2504 		/* Check and drain ih1 ring if cam not available */
2505 		if (adev->irq.ih1.ring_size) {
2506 			ih = &adev->irq.ih1;
2507 			checkpoint_wptr = amdgpu_ih_get_wptr(adev, ih);
2508 			if (ih->rptr != checkpoint_wptr) {
2509 				svms->checkpoint_ts[i] =
2510 					amdgpu_ih_decode_iv_ts(adev, ih, checkpoint_wptr, -1);
2511 				continue;
2512 			}
2513 		}
2514 
2515 		/* check if dev->irq.ih_soft is not empty */
2516 		ih = &adev->irq.ih_soft;
2517 		checkpoint_wptr = amdgpu_ih_get_wptr(adev, ih);
2518 		if (ih->rptr != checkpoint_wptr)
2519 			svms->checkpoint_ts[i] = amdgpu_ih_decode_iv_ts(adev, ih, checkpoint_wptr, -1);
2520 	}
2521 
2522 	unmap_parent = start <= prange->start && last >= prange->last;
2523 
2524 	list_for_each_entry(pchild, &prange->child_list, child_list) {
2525 		mutex_lock_nested(&pchild->lock, 1);
2526 		s = max(start, pchild->start);
2527 		l = min(last, pchild->last);
2528 		if (l >= s)
2529 			svm_range_unmap_from_gpus(pchild, s, l, trigger);
2530 		svm_range_unmap_split(mm, prange, pchild, start, last);
2531 		mutex_unlock(&pchild->lock);
2532 	}
2533 	s = max(start, prange->start);
2534 	l = min(last, prange->last);
2535 	if (l >= s)
2536 		svm_range_unmap_from_gpus(prange, s, l, trigger);
2537 	svm_range_unmap_split(mm, prange, prange, start, last);
2538 
2539 	if (unmap_parent)
2540 		svm_range_add_list_work(svms, prange, mm, SVM_OP_UNMAP_RANGE);
2541 	else
2542 		svm_range_add_list_work(svms, prange, mm,
2543 					SVM_OP_UPDATE_RANGE_NOTIFIER);
2544 	schedule_deferred_list_work(svms);
2545 
2546 	kfd_unref_process(p);
2547 }
2548 
2549 /**
2550  * svm_range_cpu_invalidate_pagetables - interval notifier callback
2551  * @mni: mmu_interval_notifier struct
2552  * @range: mmu_notifier_range struct
2553  * @cur_seq: value to pass to mmu_interval_set_seq()
2554  *
2555  * If event is MMU_NOTIFY_UNMAP, this is from CPU unmap range, otherwise, it
2556  * is from migration, or CPU page invalidation callback.
2557  *
2558  * For unmap event, unmap range from GPUs, remove prange from svms in a delayed
2559  * work thread, and split prange if only part of prange is unmapped.
2560  *
2561  * For invalidation event, if GPU retry fault is not enabled, evict the queues,
2562  * then schedule svm_range_restore_work to update GPU mapping and resume queues.
2563  * If GPU retry fault is enabled, unmap the svm range from GPU, retry fault will
2564  * update GPU mapping to recover.
2565  *
2566  * Context: mmap lock, notifier_invalidate_start lock are held
2567  *          for invalidate event, prange lock is held if this is from migration
2568  */
2569 static bool
2570 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
2571 				    const struct mmu_notifier_range *range,
2572 				    unsigned long cur_seq)
2573 {
2574 	struct svm_range *prange;
2575 	unsigned long start;
2576 	unsigned long last;
2577 
2578 	if (range->event == MMU_NOTIFY_RELEASE)
2579 		return true;
2580 	if (!mmget_not_zero(mni->mm))
2581 		return true;
2582 
2583 	start = mni->interval_tree.start;
2584 	last = mni->interval_tree.last;
2585 	start = max(start, range->start) >> PAGE_SHIFT;
2586 	last = min(last, range->end - 1) >> PAGE_SHIFT;
2587 	pr_debug("[0x%lx 0x%lx] range[0x%lx 0x%lx] notifier[0x%lx 0x%lx] %d\n",
2588 		 start, last, range->start >> PAGE_SHIFT,
2589 		 (range->end - 1) >> PAGE_SHIFT,
2590 		 mni->interval_tree.start >> PAGE_SHIFT,
2591 		 mni->interval_tree.last >> PAGE_SHIFT, range->event);
2592 
2593 	prange = container_of(mni, struct svm_range, notifier);
2594 
2595 	svm_range_lock(prange);
2596 	mmu_interval_set_seq(mni, cur_seq);
2597 
2598 	switch (range->event) {
2599 	case MMU_NOTIFY_UNMAP:
2600 		svm_range_unmap_from_cpu(mni->mm, prange, start, last);
2601 		break;
2602 	default:
2603 		svm_range_evict(prange, mni->mm, start, last, range->event);
2604 		break;
2605 	}
2606 
2607 	svm_range_unlock(prange);
2608 	mmput(mni->mm);
2609 
2610 	return true;
2611 }
2612 
2613 /**
2614  * svm_range_from_addr - find svm range from fault address
2615  * @svms: svm range list header
2616  * @addr: address to search range interval tree, in pages
2617  * @parent: parent range if range is on child list
2618  *
2619  * Context: The caller must hold svms->lock
2620  *
2621  * Return: the svm_range found or NULL
2622  */
2623 struct svm_range *
2624 svm_range_from_addr(struct svm_range_list *svms, unsigned long addr,
2625 		    struct svm_range **parent)
2626 {
2627 	struct interval_tree_node *node;
2628 	struct svm_range *prange;
2629 	struct svm_range *pchild;
2630 
2631 	node = interval_tree_iter_first(&svms->objects, addr, addr);
2632 	if (!node)
2633 		return NULL;
2634 
2635 	prange = container_of(node, struct svm_range, it_node);
2636 	pr_debug("address 0x%lx prange [0x%lx 0x%lx] node [0x%lx 0x%lx]\n",
2637 		 addr, prange->start, prange->last, node->start, node->last);
2638 
2639 	if (addr >= prange->start && addr <= prange->last) {
2640 		if (parent)
2641 			*parent = prange;
2642 		return prange;
2643 	}
2644 	list_for_each_entry(pchild, &prange->child_list, child_list)
2645 		if (addr >= pchild->start && addr <= pchild->last) {
2646 			pr_debug("found address 0x%lx pchild [0x%lx 0x%lx]\n",
2647 				 addr, pchild->start, pchild->last);
2648 			if (parent)
2649 				*parent = prange;
2650 			return pchild;
2651 		}
2652 
2653 	return NULL;
2654 }
2655 
2656 /* svm_range_best_restore_location - decide the best fault restore location
2657  * @prange: svm range structure
2658  * @adev: the GPU on which vm fault happened
2659  *
2660  * This is only called when xnack is on, to decide the best location to restore
2661  * the range mapping after GPU vm fault. Caller uses the best location to do
2662  * migration if actual loc is not best location, then update GPU page table
2663  * mapping to the best location.
2664  *
2665  * If the preferred loc is accessible by faulting GPU, use preferred loc.
2666  * If vm fault gpu idx is on range ACCESSIBLE bitmap, best_loc is vm fault gpu
2667  * If vm fault gpu idx is on range ACCESSIBLE_IN_PLACE bitmap, then
2668  *    if range actual loc is cpu, best_loc is cpu
2669  *    if vm fault gpu is on xgmi same hive of range actual loc gpu, best_loc is
2670  *    range actual loc.
2671  * Otherwise, GPU no access, best_loc is -1.
2672  *
2673  * Return:
2674  * -1 means vm fault GPU no access
2675  * 0 for CPU or GPU id
2676  */
2677 static int32_t
2678 svm_range_best_restore_location(struct svm_range *prange,
2679 				struct kfd_node *node,
2680 				int32_t *gpuidx)
2681 {
2682 	struct kfd_node *bo_node, *preferred_node;
2683 	struct kfd_process *p;
2684 	uint32_t gpuid;
2685 	int r;
2686 
2687 	p = container_of(prange->svms, struct kfd_process, svms);
2688 
2689 	r = kfd_process_gpuid_from_node(p, node, &gpuid, gpuidx);
2690 	if (r < 0) {
2691 		pr_debug("failed to get gpuid from kgd\n");
2692 		return -1;
2693 	}
2694 
2695 	if (node->adev->flags & AMD_IS_APU)
2696 		return 0;
2697 
2698 	if (prange->preferred_loc == gpuid ||
2699 	    prange->preferred_loc == KFD_IOCTL_SVM_LOCATION_SYSMEM) {
2700 		return prange->preferred_loc;
2701 	} else if (prange->preferred_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
2702 		preferred_node = svm_range_get_node_by_id(prange, prange->preferred_loc);
2703 		if (preferred_node && svm_nodes_in_same_hive(node, preferred_node))
2704 			return prange->preferred_loc;
2705 		/* fall through */
2706 	}
2707 
2708 	if (test_bit(*gpuidx, prange->bitmap_access))
2709 		return gpuid;
2710 
2711 	if (test_bit(*gpuidx, prange->bitmap_aip)) {
2712 		if (!prange->actual_loc)
2713 			return 0;
2714 
2715 		bo_node = svm_range_get_node_by_id(prange, prange->actual_loc);
2716 		if (bo_node && svm_nodes_in_same_hive(node, bo_node))
2717 			return prange->actual_loc;
2718 		else
2719 			return 0;
2720 	}
2721 
2722 	return -1;
2723 }
2724 
2725 static int
2726 svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
2727 			       unsigned long *start, unsigned long *last,
2728 			       bool *is_heap_stack)
2729 {
2730 	struct vm_area_struct *vma;
2731 	struct interval_tree_node *node;
2732 	struct rb_node *rb_node;
2733 	unsigned long start_limit, end_limit;
2734 
2735 	vma = vma_lookup(p->mm, addr << PAGE_SHIFT);
2736 	if (!vma) {
2737 		pr_debug("VMA does not exist in address [0x%llx]\n", addr);
2738 		return -EFAULT;
2739 	}
2740 
2741 	*is_heap_stack = vma_is_initial_heap(vma) || vma_is_initial_stack(vma);
2742 
2743 	start_limit = max(vma->vm_start >> PAGE_SHIFT,
2744 		      (unsigned long)ALIGN_DOWN(addr, 1UL << p->svms.default_granularity));
2745 	end_limit = min(vma->vm_end >> PAGE_SHIFT,
2746 		    (unsigned long)ALIGN(addr + 1, 1UL << p->svms.default_granularity));
2747 
2748 	/* First range that starts after the fault address */
2749 	node = interval_tree_iter_first(&p->svms.objects, addr + 1, ULONG_MAX);
2750 	if (node) {
2751 		end_limit = min(end_limit, node->start);
2752 		/* Last range that ends before the fault address */
2753 		rb_node = rb_prev(&node->rb);
2754 	} else {
2755 		/* Last range must end before addr because
2756 		 * there was no range after addr
2757 		 */
2758 		rb_node = rb_last(&p->svms.objects.rb_root);
2759 	}
2760 	if (rb_node) {
2761 		node = container_of(rb_node, struct interval_tree_node, rb);
2762 		if (node->last >= addr) {
2763 			WARN(1, "Overlap with prev node and page fault addr\n");
2764 			return -EFAULT;
2765 		}
2766 		start_limit = max(start_limit, node->last + 1);
2767 	}
2768 
2769 	*start = start_limit;
2770 	*last = end_limit - 1;
2771 
2772 	pr_debug("vma [0x%lx 0x%lx] range [0x%lx 0x%lx] is_heap_stack %d\n",
2773 		 vma->vm_start >> PAGE_SHIFT, vma->vm_end >> PAGE_SHIFT,
2774 		 *start, *last, *is_heap_stack);
2775 
2776 	return 0;
2777 }
2778 
2779 static int
2780 svm_range_check_vm_userptr(struct kfd_process *p, uint64_t start, uint64_t last,
2781 			   uint64_t *bo_s, uint64_t *bo_l)
2782 {
2783 	struct amdgpu_bo_va_mapping *mapping;
2784 	struct interval_tree_node *node;
2785 	struct amdgpu_bo *bo = NULL;
2786 	unsigned long userptr;
2787 	uint32_t i;
2788 	int r;
2789 
2790 	for (i = 0; i < p->n_pdds; i++) {
2791 		struct amdgpu_vm *vm;
2792 
2793 		if (!p->pdds[i]->drm_priv)
2794 			continue;
2795 
2796 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
2797 		r = amdgpu_bo_reserve(vm->root.bo, false);
2798 		if (r)
2799 			return r;
2800 
2801 		/* Check userptr by searching entire vm->va interval tree */
2802 		node = interval_tree_iter_first(&vm->va, 0, ~0ULL);
2803 		while (node) {
2804 			mapping = container_of((struct rb_node *)node,
2805 					       struct amdgpu_bo_va_mapping, rb);
2806 			bo = mapping->bo_va->base.bo;
2807 
2808 			if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm,
2809 							 start << PAGE_SHIFT,
2810 							 last << PAGE_SHIFT,
2811 							 &userptr)) {
2812 				node = interval_tree_iter_next(node, 0, ~0ULL);
2813 				continue;
2814 			}
2815 
2816 			pr_debug("[0x%llx 0x%llx] already userptr mapped\n",
2817 				 start, last);
2818 			if (bo_s && bo_l) {
2819 				*bo_s = userptr >> PAGE_SHIFT;
2820 				*bo_l = *bo_s + bo->tbo.ttm->num_pages - 1;
2821 			}
2822 			amdgpu_bo_unreserve(vm->root.bo);
2823 			return -EADDRINUSE;
2824 		}
2825 		amdgpu_bo_unreserve(vm->root.bo);
2826 	}
2827 	return 0;
2828 }
2829 
2830 static struct
2831 svm_range *svm_range_create_unregistered_range(struct kfd_node *node,
2832 						struct kfd_process *p,
2833 						struct mm_struct *mm,
2834 						int64_t addr)
2835 {
2836 	struct svm_range *prange = NULL;
2837 	unsigned long start, last;
2838 	uint32_t gpuid, gpuidx;
2839 	bool is_heap_stack;
2840 	uint64_t bo_s = 0;
2841 	uint64_t bo_l = 0;
2842 	int r;
2843 
2844 	if (svm_range_get_range_boundaries(p, addr, &start, &last,
2845 					   &is_heap_stack))
2846 		return NULL;
2847 
2848 	r = svm_range_check_vm(p, start, last, &bo_s, &bo_l);
2849 	if (r != -EADDRINUSE)
2850 		r = svm_range_check_vm_userptr(p, start, last, &bo_s, &bo_l);
2851 
2852 	if (r == -EADDRINUSE) {
2853 		if (addr >= bo_s && addr <= bo_l)
2854 			return NULL;
2855 
2856 		/* Create one page svm range if 2MB range overlapping */
2857 		start = addr;
2858 		last = addr;
2859 	}
2860 
2861 	prange = svm_range_new(&p->svms, start, last, true);
2862 	if (!prange) {
2863 		pr_debug("Failed to create prange in address [0x%llx]\n", addr);
2864 		return NULL;
2865 	}
2866 	if (kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx)) {
2867 		pr_debug("failed to get gpuid from kgd\n");
2868 		svm_range_free(prange, true);
2869 		return NULL;
2870 	}
2871 
2872 	if (is_heap_stack)
2873 		prange->preferred_loc = KFD_IOCTL_SVM_LOCATION_SYSMEM;
2874 
2875 	svm_range_add_to_svms(prange);
2876 	svm_range_add_notifier_locked(mm, prange);
2877 
2878 	return prange;
2879 }
2880 
2881 /* svm_range_skip_recover - decide if prange can be recovered
2882  * @prange: svm range structure
2883  *
2884  * GPU vm retry fault handle skip recover the range for cases:
2885  * 1. prange is on deferred list to be removed after unmap, it is stale fault,
2886  *    deferred list work will drain the stale fault before free the prange.
2887  * 2. prange is on deferred list to add interval notifier after split, or
2888  * 3. prange is child range, it is split from parent prange, recover later
2889  *    after interval notifier is added.
2890  *
2891  * Return: true to skip recover, false to recover
2892  */
2893 static bool svm_range_skip_recover(struct svm_range *prange)
2894 {
2895 	struct svm_range_list *svms = prange->svms;
2896 
2897 	spin_lock(&svms->deferred_list_lock);
2898 	if (list_empty(&prange->deferred_list) &&
2899 	    list_empty(&prange->child_list)) {
2900 		spin_unlock(&svms->deferred_list_lock);
2901 		return false;
2902 	}
2903 	spin_unlock(&svms->deferred_list_lock);
2904 
2905 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2906 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] unmapped\n",
2907 			 svms, prange, prange->start, prange->last);
2908 		return true;
2909 	}
2910 	if (prange->work_item.op == SVM_OP_ADD_RANGE_AND_MAP ||
2911 	    prange->work_item.op == SVM_OP_ADD_RANGE) {
2912 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] not added yet\n",
2913 			 svms, prange, prange->start, prange->last);
2914 		return true;
2915 	}
2916 	return false;
2917 }
2918 
2919 static void
2920 svm_range_count_fault(struct kfd_node *node, struct kfd_process *p,
2921 		      int32_t gpuidx)
2922 {
2923 	struct kfd_process_device *pdd;
2924 
2925 	/* fault is on different page of same range
2926 	 * or fault is skipped to recover later
2927 	 * or fault is on invalid virtual address
2928 	 */
2929 	if (gpuidx == MAX_GPU_INSTANCE) {
2930 		uint32_t gpuid;
2931 		int r;
2932 
2933 		r = kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx);
2934 		if (r < 0)
2935 			return;
2936 	}
2937 
2938 	/* fault is recovered
2939 	 * or fault cannot recover because GPU no access on the range
2940 	 */
2941 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
2942 	if (pdd)
2943 		WRITE_ONCE(pdd->faults, pdd->faults + 1);
2944 }
2945 
2946 static bool
2947 svm_fault_allowed(struct vm_area_struct *vma, bool write_fault)
2948 {
2949 	unsigned long requested = VM_READ;
2950 
2951 	if (write_fault)
2952 		requested |= VM_WRITE;
2953 
2954 	pr_debug("requested 0x%lx, vma permission flags 0x%lx\n", requested,
2955 		vma->vm_flags);
2956 	return (vma->vm_flags & requested) == requested;
2957 }
2958 
2959 int
2960 svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
2961 			uint32_t vmid, uint32_t node_id,
2962 			uint64_t addr, uint64_t ts, bool write_fault)
2963 {
2964 	unsigned long start, last, size;
2965 	struct mm_struct *mm = NULL;
2966 	struct svm_range_list *svms;
2967 	struct svm_range *prange;
2968 	struct kfd_process *p;
2969 	ktime_t timestamp = ktime_get_boottime();
2970 	struct kfd_node *node;
2971 	int32_t best_loc;
2972 	int32_t gpuid, gpuidx = MAX_GPU_INSTANCE;
2973 	bool write_locked = false;
2974 	struct vm_area_struct *vma;
2975 	bool migration = false;
2976 	int r = 0;
2977 
2978 	if (!KFD_IS_SVM_API_SUPPORTED(adev)) {
2979 		pr_debug("device does not support SVM\n");
2980 		return -EFAULT;
2981 	}
2982 
2983 	p = kfd_lookup_process_by_pasid(pasid, NULL);
2984 	if (!p) {
2985 		pr_debug("kfd process not founded pasid 0x%x\n", pasid);
2986 		return 0;
2987 	}
2988 	svms = &p->svms;
2989 
2990 	pr_debug("restoring svms 0x%p fault address 0x%llx\n", svms, addr);
2991 
2992 	if (atomic_read(&svms->drain_pagefaults)) {
2993 		pr_debug("page fault handling disabled, drop fault 0x%llx\n", addr);
2994 		r = 0;
2995 		goto out;
2996 	}
2997 
2998 	node = kfd_node_by_irq_ids(adev, node_id, vmid);
2999 	if (!node) {
3000 		pr_debug("kfd node does not exist node_id: %d, vmid: %d\n", node_id,
3001 			 vmid);
3002 		r = -EFAULT;
3003 		goto out;
3004 	}
3005 
3006 	if (kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx)) {
3007 		pr_debug("failed to get gpuid/gpuidex for node_id: %d\n", node_id);
3008 		r = -EFAULT;
3009 		goto out;
3010 	}
3011 
3012 	/* check if this page fault time stamp is before svms->checkpoint_ts */
3013 	if (svms->checkpoint_ts[gpuidx] != 0) {
3014 		if (amdgpu_ih_ts_after(ts,  svms->checkpoint_ts[gpuidx])) {
3015 			pr_debug("draining retry fault, drop fault 0x%llx\n", addr);
3016 			r = 0;
3017 			goto out;
3018 		} else
3019 			/* ts is after svms->checkpoint_ts now, reset svms->checkpoint_ts
3020 			 * to zero to avoid following ts wrap around give wrong comparing
3021 			 */
3022 			svms->checkpoint_ts[gpuidx] = 0;
3023 	}
3024 
3025 	if (!p->xnack_enabled) {
3026 		pr_debug("XNACK not enabled for pasid 0x%x\n", pasid);
3027 		r = -EFAULT;
3028 		goto out;
3029 	}
3030 
3031 	/* p->lead_thread is available as kfd_process_wq_release flush the work
3032 	 * before releasing task ref.
3033 	 */
3034 	mm = get_task_mm(p->lead_thread);
3035 	if (!mm) {
3036 		pr_debug("svms 0x%p failed to get mm\n", svms);
3037 		r = 0;
3038 		goto out;
3039 	}
3040 
3041 	mmap_read_lock(mm);
3042 retry_write_locked:
3043 	mutex_lock(&svms->lock);
3044 	prange = svm_range_from_addr(svms, addr, NULL);
3045 	if (!prange) {
3046 		pr_debug("failed to find prange svms 0x%p address [0x%llx]\n",
3047 			 svms, addr);
3048 		if (!write_locked) {
3049 			/* Need the write lock to create new range with MMU notifier.
3050 			 * Also flush pending deferred work to make sure the interval
3051 			 * tree is up to date before we add a new range
3052 			 */
3053 			mutex_unlock(&svms->lock);
3054 			mmap_read_unlock(mm);
3055 			mmap_write_lock(mm);
3056 			write_locked = true;
3057 			goto retry_write_locked;
3058 		}
3059 		prange = svm_range_create_unregistered_range(node, p, mm, addr);
3060 		if (!prange) {
3061 			pr_debug("failed to create unregistered range svms 0x%p address [0x%llx]\n",
3062 				 svms, addr);
3063 			mmap_write_downgrade(mm);
3064 			r = -EFAULT;
3065 			goto out_unlock_svms;
3066 		}
3067 	}
3068 	if (write_locked)
3069 		mmap_write_downgrade(mm);
3070 
3071 	mutex_lock(&prange->migrate_mutex);
3072 
3073 	if (svm_range_skip_recover(prange)) {
3074 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
3075 		r = 0;
3076 		goto out_unlock_range;
3077 	}
3078 
3079 	/* skip duplicate vm fault on different pages of same range */
3080 	if (ktime_before(timestamp, ktime_add_ns(prange->validate_timestamp,
3081 				AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING))) {
3082 		pr_debug("svms 0x%p [0x%lx %lx] already restored\n",
3083 			 svms, prange->start, prange->last);
3084 		r = 0;
3085 		goto out_unlock_range;
3086 	}
3087 
3088 	/* __do_munmap removed VMA, return success as we are handling stale
3089 	 * retry fault.
3090 	 */
3091 	vma = vma_lookup(mm, addr << PAGE_SHIFT);
3092 	if (!vma) {
3093 		pr_debug("address 0x%llx VMA is removed\n", addr);
3094 		r = 0;
3095 		goto out_unlock_range;
3096 	}
3097 
3098 	if (!svm_fault_allowed(vma, write_fault)) {
3099 		pr_debug("fault addr 0x%llx no %s permission\n", addr,
3100 			write_fault ? "write" : "read");
3101 		r = -EPERM;
3102 		goto out_unlock_range;
3103 	}
3104 
3105 	best_loc = svm_range_best_restore_location(prange, node, &gpuidx);
3106 	if (best_loc == -1) {
3107 		pr_debug("svms %p failed get best restore loc [0x%lx 0x%lx]\n",
3108 			 svms, prange->start, prange->last);
3109 		r = -EACCES;
3110 		goto out_unlock_range;
3111 	}
3112 
3113 	pr_debug("svms %p [0x%lx 0x%lx] best restore 0x%x, actual loc 0x%x\n",
3114 		 svms, prange->start, prange->last, best_loc,
3115 		 prange->actual_loc);
3116 
3117 	kfd_smi_event_page_fault_start(node, p->lead_thread->pid, addr,
3118 				       write_fault, timestamp);
3119 
3120 	/* Align migration range start and size to granularity size */
3121 	size = 1UL << prange->granularity;
3122 	start = max_t(unsigned long, ALIGN_DOWN(addr, size), prange->start);
3123 	last = min_t(unsigned long, ALIGN(addr + 1, size) - 1, prange->last);
3124 	if (prange->actual_loc != 0 || best_loc != 0) {
3125 		if (best_loc) {
3126 			r = svm_migrate_to_vram(prange, best_loc, start, last,
3127 					mm, KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU);
3128 			if (r) {
3129 				pr_debug("svm_migrate_to_vram failed (%d) at %llx, falling back to system memory\n",
3130 					 r, addr);
3131 				/* Fallback to system memory if migration to
3132 				 * VRAM failed
3133 				 */
3134 				if (prange->actual_loc && prange->actual_loc != best_loc)
3135 					r = svm_migrate_vram_to_ram(prange, mm, start, last,
3136 						KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU, NULL);
3137 				else
3138 					r = 0;
3139 			}
3140 		} else {
3141 			r = svm_migrate_vram_to_ram(prange, mm, start, last,
3142 					KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU, NULL);
3143 		}
3144 		if (r) {
3145 			pr_debug("failed %d to migrate svms %p [0x%lx 0x%lx]\n",
3146 				 r, svms, start, last);
3147 			goto out_migrate_fail;
3148 		} else {
3149 			migration = true;
3150 		}
3151 	}
3152 
3153 	r = svm_range_validate_and_map(mm, start, last, prange, gpuidx, false,
3154 				       false, false);
3155 	if (r)
3156 		pr_debug("failed %d to map svms 0x%p [0x%lx 0x%lx] to gpus\n",
3157 			 r, svms, start, last);
3158 
3159 out_migrate_fail:
3160 	kfd_smi_event_page_fault_end(node, p->lead_thread->pid, addr,
3161 				     migration);
3162 
3163 out_unlock_range:
3164 	mutex_unlock(&prange->migrate_mutex);
3165 out_unlock_svms:
3166 	mutex_unlock(&svms->lock);
3167 	mmap_read_unlock(mm);
3168 
3169 	svm_range_count_fault(node, p, gpuidx);
3170 
3171 	mmput(mm);
3172 out:
3173 	kfd_unref_process(p);
3174 
3175 	if (r == -EAGAIN) {
3176 		pr_debug("recover vm fault later\n");
3177 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
3178 		r = 0;
3179 	}
3180 	return r;
3181 }
3182 
3183 int
3184 svm_range_switch_xnack_reserve_mem(struct kfd_process *p, bool xnack_enabled)
3185 {
3186 	struct svm_range *prange, *pchild;
3187 	uint64_t reserved_size = 0;
3188 	uint64_t size;
3189 	int r = 0;
3190 
3191 	pr_debug("switching xnack from %d to %d\n", p->xnack_enabled, xnack_enabled);
3192 
3193 	mutex_lock(&p->svms.lock);
3194 
3195 	list_for_each_entry(prange, &p->svms.list, list) {
3196 		svm_range_lock(prange);
3197 		list_for_each_entry(pchild, &prange->child_list, child_list) {
3198 			size = (pchild->last - pchild->start + 1) << PAGE_SHIFT;
3199 			if (xnack_enabled) {
3200 				amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3201 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3202 			} else {
3203 				r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3204 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3205 				if (r)
3206 					goto out_unlock;
3207 				reserved_size += size;
3208 			}
3209 		}
3210 
3211 		size = (prange->last - prange->start + 1) << PAGE_SHIFT;
3212 		if (xnack_enabled) {
3213 			amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3214 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3215 		} else {
3216 			r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3217 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3218 			if (r)
3219 				goto out_unlock;
3220 			reserved_size += size;
3221 		}
3222 out_unlock:
3223 		svm_range_unlock(prange);
3224 		if (r)
3225 			break;
3226 	}
3227 
3228 	if (r)
3229 		amdgpu_amdkfd_unreserve_mem_limit(NULL, reserved_size,
3230 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3231 	else
3232 		/* Change xnack mode must be inside svms lock, to avoid race with
3233 		 * svm_range_deferred_list_work unreserve memory in parallel.
3234 		 */
3235 		p->xnack_enabled = xnack_enabled;
3236 
3237 	mutex_unlock(&p->svms.lock);
3238 	return r;
3239 }
3240 
3241 void svm_range_list_fini(struct kfd_process *p)
3242 {
3243 	struct svm_range *prange;
3244 	struct svm_range *next;
3245 
3246 	pr_debug("process pid %d svms 0x%p\n", p->lead_thread->pid,
3247 		 &p->svms);
3248 
3249 	cancel_delayed_work_sync(&p->svms.restore_work);
3250 
3251 	/* Ensure list work is finished before process is destroyed */
3252 	flush_work(&p->svms.deferred_list_work);
3253 
3254 	/*
3255 	 * Ensure no retry fault comes in afterwards, as page fault handler will
3256 	 * not find kfd process and take mm lock to recover fault.
3257 	 * stop kfd page fault handing, then wait pending page faults got drained
3258 	 */
3259 	atomic_set(&p->svms.drain_pagefaults, 1);
3260 	svm_range_drain_retry_fault(&p->svms);
3261 
3262 	list_for_each_entry_safe(prange, next, &p->svms.list, list) {
3263 		svm_range_unlink(prange);
3264 		svm_range_remove_notifier(prange);
3265 		svm_range_free(prange, true);
3266 	}
3267 
3268 	mutex_destroy(&p->svms.lock);
3269 
3270 	pr_debug("process pid %d svms 0x%p done\n",
3271 		p->lead_thread->pid, &p->svms);
3272 }
3273 
3274 int svm_range_list_init(struct kfd_process *p)
3275 {
3276 	struct svm_range_list *svms = &p->svms;
3277 	int i;
3278 
3279 	svms->objects = RB_ROOT_CACHED;
3280 	mutex_init(&svms->lock);
3281 	INIT_LIST_HEAD(&svms->list);
3282 	atomic_set(&svms->evicted_ranges, 0);
3283 	atomic_set(&svms->drain_pagefaults, 0);
3284 	INIT_DELAYED_WORK(&svms->restore_work, svm_range_restore_work);
3285 	INIT_WORK(&svms->deferred_list_work, svm_range_deferred_list_work);
3286 	INIT_LIST_HEAD(&svms->deferred_range_list);
3287 	INIT_LIST_HEAD(&svms->criu_svm_metadata_list);
3288 	spin_lock_init(&svms->deferred_list_lock);
3289 
3290 	for (i = 0; i < p->n_pdds; i++)
3291 		if (KFD_IS_SVM_API_SUPPORTED(p->pdds[i]->dev->adev))
3292 			bitmap_set(svms->bitmap_supported, i, 1);
3293 
3294 	 /* Value of default granularity cannot exceed 0x1B, the
3295 	  * number of pages supported by a 4-level paging table
3296 	  */
3297 	svms->default_granularity = min_t(u8, amdgpu_svm_default_granularity, 0x1B);
3298 	pr_debug("Default SVM Granularity to use: %d\n", svms->default_granularity);
3299 
3300 	return 0;
3301 }
3302 
3303 /**
3304  * svm_range_check_vm - check if virtual address range mapped already
3305  * @p: current kfd_process
3306  * @start: range start address, in pages
3307  * @last: range last address, in pages
3308  * @bo_s: mapping start address in pages if address range already mapped
3309  * @bo_l: mapping last address in pages if address range already mapped
3310  *
3311  * The purpose is to avoid virtual address ranges already allocated by
3312  * kfd_ioctl_alloc_memory_of_gpu ioctl.
3313  * It looks for each pdd in the kfd_process.
3314  *
3315  * Context: Process context
3316  *
3317  * Return 0 - OK, if the range is not mapped.
3318  * Otherwise error code:
3319  * -EADDRINUSE - if address is mapped already by kfd_ioctl_alloc_memory_of_gpu
3320  * -ERESTARTSYS - A wait for the buffer to become unreserved was interrupted by
3321  * a signal. Release all buffer reservations and return to user-space.
3322  */
3323 static int
3324 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
3325 		   uint64_t *bo_s, uint64_t *bo_l)
3326 {
3327 	struct amdgpu_bo_va_mapping *mapping;
3328 	struct interval_tree_node *node;
3329 	uint32_t i;
3330 	int r;
3331 
3332 	for (i = 0; i < p->n_pdds; i++) {
3333 		struct amdgpu_vm *vm;
3334 
3335 		if (!p->pdds[i]->drm_priv)
3336 			continue;
3337 
3338 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
3339 		r = amdgpu_bo_reserve(vm->root.bo, false);
3340 		if (r)
3341 			return r;
3342 
3343 		node = interval_tree_iter_first(&vm->va, start, last);
3344 		if (node) {
3345 			pr_debug("range [0x%llx 0x%llx] already TTM mapped\n",
3346 				 start, last);
3347 			mapping = container_of((struct rb_node *)node,
3348 					       struct amdgpu_bo_va_mapping, rb);
3349 			if (bo_s && bo_l) {
3350 				*bo_s = mapping->start;
3351 				*bo_l = mapping->last;
3352 			}
3353 			amdgpu_bo_unreserve(vm->root.bo);
3354 			return -EADDRINUSE;
3355 		}
3356 		amdgpu_bo_unreserve(vm->root.bo);
3357 	}
3358 
3359 	return 0;
3360 }
3361 
3362 /**
3363  * svm_range_is_valid - check if virtual address range is valid
3364  * @p: current kfd_process
3365  * @start: range start address, in pages
3366  * @size: range size, in pages
3367  *
3368  * Valid virtual address range means it belongs to one or more VMAs
3369  *
3370  * Context: Process context
3371  *
3372  * Return:
3373  *  0 - OK, otherwise error code
3374  */
3375 static int
3376 svm_range_is_valid(struct kfd_process *p, uint64_t start, uint64_t size)
3377 {
3378 	const unsigned long device_vma = VM_IO | VM_PFNMAP | VM_MIXEDMAP;
3379 	struct vm_area_struct *vma;
3380 	unsigned long end;
3381 	unsigned long start_unchg = start;
3382 
3383 	start <<= PAGE_SHIFT;
3384 	end = start + (size << PAGE_SHIFT);
3385 	do {
3386 		vma = vma_lookup(p->mm, start);
3387 		if (!vma || (vma->vm_flags & device_vma))
3388 			return -EFAULT;
3389 		start = min(end, vma->vm_end);
3390 	} while (start < end);
3391 
3392 	return svm_range_check_vm(p, start_unchg, (end - 1) >> PAGE_SHIFT, NULL,
3393 				  NULL);
3394 }
3395 
3396 /**
3397  * svm_range_best_prefetch_location - decide the best prefetch location
3398  * @prange: svm range structure
3399  *
3400  * For xnack off:
3401  * If range map to single GPU, the best prefetch location is prefetch_loc, which
3402  * can be CPU or GPU.
3403  *
3404  * If range is ACCESS or ACCESS_IN_PLACE by mGPUs, only if mGPU connection on
3405  * XGMI same hive, the best prefetch location is prefetch_loc GPU, othervise
3406  * the best prefetch location is always CPU, because GPU can not have coherent
3407  * mapping VRAM of other GPUs even with large-BAR PCIe connection.
3408  *
3409  * For xnack on:
3410  * If range is not ACCESS_IN_PLACE by mGPUs, the best prefetch location is
3411  * prefetch_loc, other GPU access will generate vm fault and trigger migration.
3412  *
3413  * If range is ACCESS_IN_PLACE by mGPUs, only if mGPU connection on XGMI same
3414  * hive, the best prefetch location is prefetch_loc GPU, otherwise the best
3415  * prefetch location is always CPU.
3416  *
3417  * Context: Process context
3418  *
3419  * Return:
3420  * 0 for CPU or GPU id
3421  */
3422 static uint32_t
3423 svm_range_best_prefetch_location(struct svm_range *prange)
3424 {
3425 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
3426 	uint32_t best_loc = prange->prefetch_loc;
3427 	struct kfd_process_device *pdd;
3428 	struct kfd_node *bo_node;
3429 	struct kfd_process *p;
3430 	uint32_t gpuidx;
3431 
3432 	p = container_of(prange->svms, struct kfd_process, svms);
3433 
3434 	if (!best_loc || best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED)
3435 		goto out;
3436 
3437 	bo_node = svm_range_get_node_by_id(prange, best_loc);
3438 	if (!bo_node) {
3439 		WARN_ONCE(1, "failed to get valid kfd node at id%x\n", best_loc);
3440 		best_loc = 0;
3441 		goto out;
3442 	}
3443 
3444 	if (bo_node->adev->flags & AMD_IS_APU) {
3445 		best_loc = 0;
3446 		goto out;
3447 	}
3448 
3449 	if (p->xnack_enabled)
3450 		bitmap_copy(bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
3451 	else
3452 		bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
3453 			  MAX_GPU_INSTANCE);
3454 
3455 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
3456 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
3457 		if (!pdd) {
3458 			pr_debug("failed to get device by idx 0x%x\n", gpuidx);
3459 			continue;
3460 		}
3461 
3462 		if (pdd->dev->adev == bo_node->adev)
3463 			continue;
3464 
3465 		if (!svm_nodes_in_same_hive(pdd->dev, bo_node)) {
3466 			best_loc = 0;
3467 			break;
3468 		}
3469 	}
3470 
3471 out:
3472 	pr_debug("xnack %d svms 0x%p [0x%lx 0x%lx] best loc 0x%x\n",
3473 		 p->xnack_enabled, &p->svms, prange->start, prange->last,
3474 		 best_loc);
3475 
3476 	return best_loc;
3477 }
3478 
3479 /* svm_range_trigger_migration - start page migration if prefetch loc changed
3480  * @mm: current process mm_struct
3481  * @prange: svm range structure
3482  * @migrated: output, true if migration is triggered
3483  *
3484  * If range perfetch_loc is GPU, actual loc is cpu 0, then migrate the range
3485  * from ram to vram.
3486  * If range prefetch_loc is cpu 0, actual loc is GPU, then migrate the range
3487  * from vram to ram.
3488  *
3489  * If GPU vm fault retry is not enabled, migration interact with MMU notifier
3490  * and restore work:
3491  * 1. migrate_vma_setup invalidate pages, MMU notifier callback svm_range_evict
3492  *    stops all queues, schedule restore work
3493  * 2. svm_range_restore_work wait for migration is done by
3494  *    a. svm_range_validate_vram takes prange->migrate_mutex
3495  *    b. svm_range_validate_ram HMM get pages wait for CPU fault handle returns
3496  * 3. restore work update mappings of GPU, resume all queues.
3497  *
3498  * Context: Process context
3499  *
3500  * Return:
3501  * 0 - OK, otherwise - error code of migration
3502  */
3503 static int
3504 svm_range_trigger_migration(struct mm_struct *mm, struct svm_range *prange,
3505 			    bool *migrated)
3506 {
3507 	uint32_t best_loc;
3508 	int r = 0;
3509 
3510 	*migrated = false;
3511 	best_loc = svm_range_best_prefetch_location(prange);
3512 
3513 	/* when best_loc is a gpu node and same as prange->actual_loc
3514 	 * we still need do migration as prange->actual_loc !=0 does
3515 	 * not mean all pages in prange are vram. hmm migrate will pick
3516 	 * up right pages during migration.
3517 	 */
3518 	if ((best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED) ||
3519 	    (best_loc == 0 && prange->actual_loc == 0))
3520 		return 0;
3521 
3522 	if (!best_loc) {
3523 		r = svm_migrate_vram_to_ram(prange, mm, prange->start, prange->last,
3524 					KFD_MIGRATE_TRIGGER_PREFETCH, NULL);
3525 		*migrated = !r;
3526 		return r;
3527 	}
3528 
3529 	r = svm_migrate_to_vram(prange, best_loc, prange->start, prange->last,
3530 				mm, KFD_MIGRATE_TRIGGER_PREFETCH);
3531 	*migrated = !r;
3532 
3533 	return 0;
3534 }
3535 
3536 int svm_range_schedule_evict_svm_bo(struct amdgpu_amdkfd_fence *fence)
3537 {
3538 	/* Dereferencing fence->svm_bo is safe here because the fence hasn't
3539 	 * signaled yet and we're under the protection of the fence->lock.
3540 	 * After the fence is signaled in svm_range_bo_release, we cannot get
3541 	 * here any more.
3542 	 *
3543 	 * Reference is dropped in svm_range_evict_svm_bo_worker.
3544 	 */
3545 	if (svm_bo_ref_unless_zero(fence->svm_bo)) {
3546 		WRITE_ONCE(fence->svm_bo->evicting, 1);
3547 		schedule_work(&fence->svm_bo->eviction_work);
3548 	}
3549 
3550 	return 0;
3551 }
3552 
3553 static void svm_range_evict_svm_bo_worker(struct work_struct *work)
3554 {
3555 	struct svm_range_bo *svm_bo;
3556 	struct mm_struct *mm;
3557 	int r = 0;
3558 
3559 	svm_bo = container_of(work, struct svm_range_bo, eviction_work);
3560 
3561 	if (mmget_not_zero(svm_bo->eviction_fence->mm)) {
3562 		mm = svm_bo->eviction_fence->mm;
3563 	} else {
3564 		svm_range_bo_unref(svm_bo);
3565 		return;
3566 	}
3567 
3568 	mmap_read_lock(mm);
3569 	spin_lock(&svm_bo->list_lock);
3570 	while (!list_empty(&svm_bo->range_list) && !r) {
3571 		struct svm_range *prange =
3572 				list_first_entry(&svm_bo->range_list,
3573 						struct svm_range, svm_bo_list);
3574 		int retries = 3;
3575 
3576 		list_del_init(&prange->svm_bo_list);
3577 		spin_unlock(&svm_bo->list_lock);
3578 
3579 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
3580 			 prange->start, prange->last);
3581 
3582 		mutex_lock(&prange->migrate_mutex);
3583 		do {
3584 			/* migrate all vram pages in this prange to sys ram
3585 			 * after that prange->actual_loc should be zero
3586 			 */
3587 			r = svm_migrate_vram_to_ram(prange, mm,
3588 					prange->start, prange->last,
3589 					KFD_MIGRATE_TRIGGER_TTM_EVICTION, NULL);
3590 		} while (!r && prange->actual_loc && --retries);
3591 
3592 		if (!r && prange->actual_loc)
3593 			pr_info_once("Migration failed during eviction");
3594 
3595 		if (!prange->actual_loc) {
3596 			mutex_lock(&prange->lock);
3597 			prange->svm_bo = NULL;
3598 			mutex_unlock(&prange->lock);
3599 		}
3600 		mutex_unlock(&prange->migrate_mutex);
3601 
3602 		spin_lock(&svm_bo->list_lock);
3603 	}
3604 	spin_unlock(&svm_bo->list_lock);
3605 	mmap_read_unlock(mm);
3606 	mmput(mm);
3607 
3608 	dma_fence_signal(&svm_bo->eviction_fence->base);
3609 
3610 	/* This is the last reference to svm_bo, after svm_range_vram_node_free
3611 	 * has been called in svm_migrate_vram_to_ram
3612 	 */
3613 	WARN_ONCE(!r && kref_read(&svm_bo->kref) != 1, "This was not the last reference\n");
3614 	svm_range_bo_unref(svm_bo);
3615 }
3616 
3617 static int
3618 svm_range_set_attr(struct kfd_process *p, struct mm_struct *mm,
3619 		   uint64_t start, uint64_t size, uint32_t nattr,
3620 		   struct kfd_ioctl_svm_attribute *attrs)
3621 {
3622 	struct amdkfd_process_info *process_info = p->kgd_process_info;
3623 	struct list_head update_list;
3624 	struct list_head insert_list;
3625 	struct list_head remove_list;
3626 	struct list_head remap_list;
3627 	struct svm_range_list *svms;
3628 	struct svm_range *prange;
3629 	struct svm_range *next;
3630 	bool update_mapping = false;
3631 	bool flush_tlb;
3632 	int r, ret = 0;
3633 
3634 	pr_debug("process pid %d svms 0x%p [0x%llx 0x%llx] pages 0x%llx\n",
3635 		 p->lead_thread->pid, &p->svms, start, start + size - 1, size);
3636 
3637 	r = svm_range_check_attr(p, nattr, attrs);
3638 	if (r)
3639 		return r;
3640 
3641 	svms = &p->svms;
3642 
3643 	mutex_lock(&process_info->lock);
3644 
3645 	svm_range_list_lock_and_flush_work(svms, mm);
3646 
3647 	r = svm_range_is_valid(p, start, size);
3648 	if (r) {
3649 		pr_debug("invalid range r=%d\n", r);
3650 		mmap_write_unlock(mm);
3651 		goto out;
3652 	}
3653 
3654 	mutex_lock(&svms->lock);
3655 
3656 	/* Add new range and split existing ranges as needed */
3657 	r = svm_range_add(p, start, size, nattr, attrs, &update_list,
3658 			  &insert_list, &remove_list, &remap_list);
3659 	if (r) {
3660 		mutex_unlock(&svms->lock);
3661 		mmap_write_unlock(mm);
3662 		goto out;
3663 	}
3664 	/* Apply changes as a transaction */
3665 	list_for_each_entry_safe(prange, next, &insert_list, list) {
3666 		svm_range_add_to_svms(prange);
3667 		svm_range_add_notifier_locked(mm, prange);
3668 	}
3669 	list_for_each_entry(prange, &update_list, update_list) {
3670 		svm_range_apply_attrs(p, prange, nattr, attrs, &update_mapping);
3671 		/* TODO: unmap ranges from GPU that lost access */
3672 	}
3673 	list_for_each_entry_safe(prange, next, &remove_list, update_list) {
3674 		pr_debug("unlink old 0x%p prange 0x%p [0x%lx 0x%lx]\n",
3675 			 prange->svms, prange, prange->start,
3676 			 prange->last);
3677 		svm_range_unlink(prange);
3678 		svm_range_remove_notifier(prange);
3679 		svm_range_free(prange, false);
3680 	}
3681 
3682 	mmap_write_downgrade(mm);
3683 	/* Trigger migrations and revalidate and map to GPUs as needed. If
3684 	 * this fails we may be left with partially completed actions. There
3685 	 * is no clean way of rolling back to the previous state in such a
3686 	 * case because the rollback wouldn't be guaranteed to work either.
3687 	 */
3688 	list_for_each_entry(prange, &update_list, update_list) {
3689 		bool migrated;
3690 
3691 		mutex_lock(&prange->migrate_mutex);
3692 
3693 		r = svm_range_trigger_migration(mm, prange, &migrated);
3694 		if (r)
3695 			goto out_unlock_range;
3696 
3697 		if (migrated && (!p->xnack_enabled ||
3698 		    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) &&
3699 		    prange->mapped_to_gpu) {
3700 			pr_debug("restore_work will update mappings of GPUs\n");
3701 			mutex_unlock(&prange->migrate_mutex);
3702 			continue;
3703 		}
3704 
3705 		if (!migrated && !update_mapping) {
3706 			mutex_unlock(&prange->migrate_mutex);
3707 			continue;
3708 		}
3709 
3710 		flush_tlb = !migrated && update_mapping && prange->mapped_to_gpu;
3711 
3712 		r = svm_range_validate_and_map(mm, prange->start, prange->last, prange,
3713 					       MAX_GPU_INSTANCE, true, true, flush_tlb);
3714 		if (r)
3715 			pr_debug("failed %d to map svm range\n", r);
3716 
3717 out_unlock_range:
3718 		mutex_unlock(&prange->migrate_mutex);
3719 		if (r)
3720 			ret = r;
3721 	}
3722 
3723 	list_for_each_entry(prange, &remap_list, update_list) {
3724 		pr_debug("Remapping prange 0x%p [0x%lx 0x%lx]\n",
3725 			 prange, prange->start, prange->last);
3726 		mutex_lock(&prange->migrate_mutex);
3727 		r = svm_range_validate_and_map(mm,  prange->start, prange->last, prange,
3728 					       MAX_GPU_INSTANCE, true, true, prange->mapped_to_gpu);
3729 		if (r)
3730 			pr_debug("failed %d on remap svm range\n", r);
3731 		mutex_unlock(&prange->migrate_mutex);
3732 		if (r)
3733 			ret = r;
3734 	}
3735 
3736 	dynamic_svm_range_dump(svms);
3737 
3738 	mutex_unlock(&svms->lock);
3739 	mmap_read_unlock(mm);
3740 out:
3741 	mutex_unlock(&process_info->lock);
3742 
3743 	pr_debug("process pid %d svms 0x%p [0x%llx 0x%llx] done, r=%d\n",
3744 		 p->lead_thread->pid, &p->svms, start, start + size - 1, r);
3745 
3746 	return ret ? ret : r;
3747 }
3748 
3749 static int
3750 svm_range_get_attr(struct kfd_process *p, struct mm_struct *mm,
3751 		   uint64_t start, uint64_t size, uint32_t nattr,
3752 		   struct kfd_ioctl_svm_attribute *attrs)
3753 {
3754 	DECLARE_BITMAP(bitmap_access, MAX_GPU_INSTANCE);
3755 	DECLARE_BITMAP(bitmap_aip, MAX_GPU_INSTANCE);
3756 	bool get_preferred_loc = false;
3757 	bool get_prefetch_loc = false;
3758 	bool get_granularity = false;
3759 	bool get_accessible = false;
3760 	bool get_flags = false;
3761 	uint64_t last = start + size - 1UL;
3762 	uint8_t granularity = 0xff;
3763 	struct interval_tree_node *node;
3764 	struct svm_range_list *svms;
3765 	struct svm_range *prange;
3766 	uint32_t prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3767 	uint32_t location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3768 	uint32_t flags_and = 0xffffffff;
3769 	uint32_t flags_or = 0;
3770 	int gpuidx;
3771 	uint32_t i;
3772 	int r = 0;
3773 
3774 	pr_debug("svms 0x%p [0x%llx 0x%llx] nattr 0x%x\n", &p->svms, start,
3775 		 start + size - 1, nattr);
3776 
3777 	/* Flush pending deferred work to avoid racing with deferred actions from
3778 	 * previous memory map changes (e.g. munmap). Concurrent memory map changes
3779 	 * can still race with get_attr because we don't hold the mmap lock. But that
3780 	 * would be a race condition in the application anyway, and undefined
3781 	 * behaviour is acceptable in that case.
3782 	 */
3783 	flush_work(&p->svms.deferred_list_work);
3784 
3785 	mmap_read_lock(mm);
3786 	r = svm_range_is_valid(p, start, size);
3787 	mmap_read_unlock(mm);
3788 	if (r) {
3789 		pr_debug("invalid range r=%d\n", r);
3790 		return r;
3791 	}
3792 
3793 	for (i = 0; i < nattr; i++) {
3794 		switch (attrs[i].type) {
3795 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3796 			get_preferred_loc = true;
3797 			break;
3798 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3799 			get_prefetch_loc = true;
3800 			break;
3801 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3802 			get_accessible = true;
3803 			break;
3804 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3805 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3806 			get_flags = true;
3807 			break;
3808 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3809 			get_granularity = true;
3810 			break;
3811 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
3812 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
3813 			fallthrough;
3814 		default:
3815 			pr_debug("get invalid attr type 0x%x\n", attrs[i].type);
3816 			return -EINVAL;
3817 		}
3818 	}
3819 
3820 	svms = &p->svms;
3821 
3822 	mutex_lock(&svms->lock);
3823 
3824 	node = interval_tree_iter_first(&svms->objects, start, last);
3825 	if (!node) {
3826 		pr_debug("range attrs not found return default values\n");
3827 		svm_range_set_default_attributes(svms, &location, &prefetch_loc,
3828 						 &granularity, &flags_and);
3829 		flags_or = flags_and;
3830 		if (p->xnack_enabled)
3831 			bitmap_copy(bitmap_access, svms->bitmap_supported,
3832 				    MAX_GPU_INSTANCE);
3833 		else
3834 			bitmap_zero(bitmap_access, MAX_GPU_INSTANCE);
3835 		bitmap_zero(bitmap_aip, MAX_GPU_INSTANCE);
3836 		goto fill_values;
3837 	}
3838 	bitmap_copy(bitmap_access, svms->bitmap_supported, MAX_GPU_INSTANCE);
3839 	bitmap_copy(bitmap_aip, svms->bitmap_supported, MAX_GPU_INSTANCE);
3840 
3841 	while (node) {
3842 		struct interval_tree_node *next;
3843 
3844 		prange = container_of(node, struct svm_range, it_node);
3845 		next = interval_tree_iter_next(node, start, last);
3846 
3847 		if (get_preferred_loc) {
3848 			if (prange->preferred_loc ==
3849 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3850 			    (location != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3851 			     location != prange->preferred_loc)) {
3852 				location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3853 				get_preferred_loc = false;
3854 			} else {
3855 				location = prange->preferred_loc;
3856 			}
3857 		}
3858 		if (get_prefetch_loc) {
3859 			if (prange->prefetch_loc ==
3860 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3861 			    (prefetch_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3862 			     prefetch_loc != prange->prefetch_loc)) {
3863 				prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3864 				get_prefetch_loc = false;
3865 			} else {
3866 				prefetch_loc = prange->prefetch_loc;
3867 			}
3868 		}
3869 		if (get_accessible) {
3870 			bitmap_and(bitmap_access, bitmap_access,
3871 				   prange->bitmap_access, MAX_GPU_INSTANCE);
3872 			bitmap_and(bitmap_aip, bitmap_aip,
3873 				   prange->bitmap_aip, MAX_GPU_INSTANCE);
3874 		}
3875 		if (get_flags) {
3876 			flags_and &= prange->flags;
3877 			flags_or |= prange->flags;
3878 		}
3879 
3880 		if (get_granularity && prange->granularity < granularity)
3881 			granularity = prange->granularity;
3882 
3883 		node = next;
3884 	}
3885 fill_values:
3886 	mutex_unlock(&svms->lock);
3887 
3888 	for (i = 0; i < nattr; i++) {
3889 		switch (attrs[i].type) {
3890 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3891 			attrs[i].value = location;
3892 			break;
3893 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3894 			attrs[i].value = prefetch_loc;
3895 			break;
3896 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3897 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
3898 							       attrs[i].value);
3899 			if (gpuidx < 0) {
3900 				pr_debug("invalid gpuid %x\n", attrs[i].value);
3901 				return -EINVAL;
3902 			}
3903 			if (test_bit(gpuidx, bitmap_access))
3904 				attrs[i].type = KFD_IOCTL_SVM_ATTR_ACCESS;
3905 			else if (test_bit(gpuidx, bitmap_aip))
3906 				attrs[i].type =
3907 					KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE;
3908 			else
3909 				attrs[i].type = KFD_IOCTL_SVM_ATTR_NO_ACCESS;
3910 			break;
3911 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3912 			attrs[i].value = flags_and;
3913 			break;
3914 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3915 			attrs[i].value = ~flags_or;
3916 			break;
3917 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3918 			attrs[i].value = (uint32_t)granularity;
3919 			break;
3920 		}
3921 	}
3922 
3923 	return 0;
3924 }
3925 
3926 int kfd_criu_resume_svm(struct kfd_process *p)
3927 {
3928 	struct kfd_ioctl_svm_attribute *set_attr_new, *set_attr = NULL;
3929 	int nattr_common = 4, nattr_accessibility = 1;
3930 	struct criu_svm_metadata *criu_svm_md = NULL;
3931 	struct svm_range_list *svms = &p->svms;
3932 	struct criu_svm_metadata *next = NULL;
3933 	uint32_t set_flags = 0xffffffff;
3934 	int i, j, num_attrs, ret = 0;
3935 	uint64_t set_attr_size;
3936 	struct mm_struct *mm;
3937 
3938 	if (list_empty(&svms->criu_svm_metadata_list)) {
3939 		pr_debug("No SVM data from CRIU restore stage 2\n");
3940 		return ret;
3941 	}
3942 
3943 	mm = get_task_mm(p->lead_thread);
3944 	if (!mm) {
3945 		pr_err("failed to get mm for the target process\n");
3946 		return -ESRCH;
3947 	}
3948 
3949 	num_attrs = nattr_common + (nattr_accessibility * p->n_pdds);
3950 
3951 	i = j = 0;
3952 	list_for_each_entry(criu_svm_md, &svms->criu_svm_metadata_list, list) {
3953 		pr_debug("criu_svm_md[%d]\n\tstart: 0x%llx size: 0x%llx (npages)\n",
3954 			 i, criu_svm_md->data.start_addr, criu_svm_md->data.size);
3955 
3956 		for (j = 0; j < num_attrs; j++) {
3957 			pr_debug("\ncriu_svm_md[%d]->attrs[%d].type : 0x%x\ncriu_svm_md[%d]->attrs[%d].value : 0x%x\n",
3958 				 i, j, criu_svm_md->data.attrs[j].type,
3959 				 i, j, criu_svm_md->data.attrs[j].value);
3960 			switch (criu_svm_md->data.attrs[j].type) {
3961 			/* During Checkpoint operation, the query for
3962 			 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC attribute might
3963 			 * return KFD_IOCTL_SVM_LOCATION_UNDEFINED if they were
3964 			 * not used by the range which was checkpointed. Care
3965 			 * must be taken to not restore with an invalid value
3966 			 * otherwise the gpuidx value will be invalid and
3967 			 * set_attr would eventually fail so just replace those
3968 			 * with another dummy attribute such as
3969 			 * KFD_IOCTL_SVM_ATTR_SET_FLAGS.
3970 			 */
3971 			case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3972 				if (criu_svm_md->data.attrs[j].value ==
3973 				    KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
3974 					criu_svm_md->data.attrs[j].type =
3975 						KFD_IOCTL_SVM_ATTR_SET_FLAGS;
3976 					criu_svm_md->data.attrs[j].value = 0;
3977 				}
3978 				break;
3979 			case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3980 				set_flags = criu_svm_md->data.attrs[j].value;
3981 				break;
3982 			default:
3983 				break;
3984 			}
3985 		}
3986 
3987 		/* CLR_FLAGS is not available via get_attr during checkpoint but
3988 		 * it needs to be inserted before restoring the ranges so
3989 		 * allocate extra space for it before calling set_attr
3990 		 */
3991 		set_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
3992 						(num_attrs + 1);
3993 		set_attr_new = krealloc(set_attr, set_attr_size,
3994 					    GFP_KERNEL);
3995 		if (!set_attr_new) {
3996 			ret = -ENOMEM;
3997 			goto exit;
3998 		}
3999 		set_attr = set_attr_new;
4000 
4001 		memcpy(set_attr, criu_svm_md->data.attrs, num_attrs *
4002 					sizeof(struct kfd_ioctl_svm_attribute));
4003 		set_attr[num_attrs].type = KFD_IOCTL_SVM_ATTR_CLR_FLAGS;
4004 		set_attr[num_attrs].value = ~set_flags;
4005 
4006 		ret = svm_range_set_attr(p, mm, criu_svm_md->data.start_addr,
4007 					 criu_svm_md->data.size, num_attrs + 1,
4008 					 set_attr);
4009 		if (ret) {
4010 			pr_err("CRIU: failed to set range attributes\n");
4011 			goto exit;
4012 		}
4013 
4014 		i++;
4015 	}
4016 exit:
4017 	kfree(set_attr);
4018 	list_for_each_entry_safe(criu_svm_md, next, &svms->criu_svm_metadata_list, list) {
4019 		pr_debug("freeing criu_svm_md[]\n\tstart: 0x%llx\n",
4020 						criu_svm_md->data.start_addr);
4021 		kfree(criu_svm_md);
4022 	}
4023 
4024 	mmput(mm);
4025 	return ret;
4026 
4027 }
4028 
4029 int kfd_criu_restore_svm(struct kfd_process *p,
4030 			 uint8_t __user *user_priv_ptr,
4031 			 uint64_t *priv_data_offset,
4032 			 uint64_t max_priv_data_size)
4033 {
4034 	uint64_t svm_priv_data_size, svm_object_md_size, svm_attrs_size;
4035 	int nattr_common = 4, nattr_accessibility = 1;
4036 	struct criu_svm_metadata *criu_svm_md = NULL;
4037 	struct svm_range_list *svms = &p->svms;
4038 	uint32_t num_devices;
4039 	int ret = 0;
4040 
4041 	num_devices = p->n_pdds;
4042 	/* Handle one SVM range object at a time, also the number of gpus are
4043 	 * assumed to be same on the restore node, checking must be done while
4044 	 * evaluating the topology earlier
4045 	 */
4046 
4047 	svm_attrs_size = sizeof(struct kfd_ioctl_svm_attribute) *
4048 		(nattr_common + nattr_accessibility * num_devices);
4049 	svm_object_md_size = sizeof(struct criu_svm_metadata) + svm_attrs_size;
4050 
4051 	svm_priv_data_size = sizeof(struct kfd_criu_svm_range_priv_data) +
4052 								svm_attrs_size;
4053 
4054 	criu_svm_md = kzalloc(svm_object_md_size, GFP_KERNEL);
4055 	if (!criu_svm_md) {
4056 		pr_err("failed to allocate memory to store svm metadata\n");
4057 		return -ENOMEM;
4058 	}
4059 	if (*priv_data_offset + svm_priv_data_size > max_priv_data_size) {
4060 		ret = -EINVAL;
4061 		goto exit;
4062 	}
4063 
4064 	ret = copy_from_user(&criu_svm_md->data, user_priv_ptr + *priv_data_offset,
4065 			     svm_priv_data_size);
4066 	if (ret) {
4067 		ret = -EFAULT;
4068 		goto exit;
4069 	}
4070 	*priv_data_offset += svm_priv_data_size;
4071 
4072 	list_add_tail(&criu_svm_md->list, &svms->criu_svm_metadata_list);
4073 
4074 	return 0;
4075 
4076 
4077 exit:
4078 	kfree(criu_svm_md);
4079 	return ret;
4080 }
4081 
4082 int svm_range_get_info(struct kfd_process *p, uint32_t *num_svm_ranges,
4083 		       uint64_t *svm_priv_data_size)
4084 {
4085 	uint64_t total_size, accessibility_size, common_attr_size;
4086 	int nattr_common = 4, nattr_accessibility = 1;
4087 	int num_devices = p->n_pdds;
4088 	struct svm_range_list *svms;
4089 	struct svm_range *prange;
4090 	uint32_t count = 0;
4091 
4092 	*svm_priv_data_size = 0;
4093 
4094 	svms = &p->svms;
4095 	if (!svms)
4096 		return -EINVAL;
4097 
4098 	mutex_lock(&svms->lock);
4099 	list_for_each_entry(prange, &svms->list, list) {
4100 		pr_debug("prange: 0x%p start: 0x%lx\t npages: 0x%llx\t end: 0x%llx\n",
4101 			 prange, prange->start, prange->npages,
4102 			 prange->start + prange->npages - 1);
4103 		count++;
4104 	}
4105 	mutex_unlock(&svms->lock);
4106 
4107 	*num_svm_ranges = count;
4108 	/* Only the accessbility attributes need to be queried for all the gpus
4109 	 * individually, remaining ones are spanned across the entire process
4110 	 * regardless of the various gpu nodes. Of the remaining attributes,
4111 	 * KFD_IOCTL_SVM_ATTR_CLR_FLAGS need not be saved.
4112 	 *
4113 	 * KFD_IOCTL_SVM_ATTR_PREFERRED_LOC
4114 	 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC
4115 	 * KFD_IOCTL_SVM_ATTR_SET_FLAGS
4116 	 * KFD_IOCTL_SVM_ATTR_GRANULARITY
4117 	 *
4118 	 * ** ACCESSBILITY ATTRIBUTES **
4119 	 * (Considered as one, type is altered during query, value is gpuid)
4120 	 * KFD_IOCTL_SVM_ATTR_ACCESS
4121 	 * KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE
4122 	 * KFD_IOCTL_SVM_ATTR_NO_ACCESS
4123 	 */
4124 	if (*num_svm_ranges > 0) {
4125 		common_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4126 			nattr_common;
4127 		accessibility_size = sizeof(struct kfd_ioctl_svm_attribute) *
4128 			nattr_accessibility * num_devices;
4129 
4130 		total_size = sizeof(struct kfd_criu_svm_range_priv_data) +
4131 			common_attr_size + accessibility_size;
4132 
4133 		*svm_priv_data_size = *num_svm_ranges * total_size;
4134 	}
4135 
4136 	pr_debug("num_svm_ranges %u total_priv_size %llu\n", *num_svm_ranges,
4137 		 *svm_priv_data_size);
4138 	return 0;
4139 }
4140 
4141 int kfd_criu_checkpoint_svm(struct kfd_process *p,
4142 			    uint8_t __user *user_priv_data,
4143 			    uint64_t *priv_data_offset)
4144 {
4145 	struct kfd_criu_svm_range_priv_data *svm_priv = NULL;
4146 	struct kfd_ioctl_svm_attribute *query_attr = NULL;
4147 	uint64_t svm_priv_data_size, query_attr_size = 0;
4148 	int index, nattr_common = 4, ret = 0;
4149 	struct svm_range_list *svms;
4150 	int num_devices = p->n_pdds;
4151 	struct svm_range *prange;
4152 	struct mm_struct *mm;
4153 
4154 	svms = &p->svms;
4155 	if (!svms)
4156 		return -EINVAL;
4157 
4158 	mm = get_task_mm(p->lead_thread);
4159 	if (!mm) {
4160 		pr_err("failed to get mm for the target process\n");
4161 		return -ESRCH;
4162 	}
4163 
4164 	query_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4165 				(nattr_common + num_devices);
4166 
4167 	query_attr = kzalloc(query_attr_size, GFP_KERNEL);
4168 	if (!query_attr) {
4169 		ret = -ENOMEM;
4170 		goto exit;
4171 	}
4172 
4173 	query_attr[0].type = KFD_IOCTL_SVM_ATTR_PREFERRED_LOC;
4174 	query_attr[1].type = KFD_IOCTL_SVM_ATTR_PREFETCH_LOC;
4175 	query_attr[2].type = KFD_IOCTL_SVM_ATTR_SET_FLAGS;
4176 	query_attr[3].type = KFD_IOCTL_SVM_ATTR_GRANULARITY;
4177 
4178 	for (index = 0; index < num_devices; index++) {
4179 		struct kfd_process_device *pdd = p->pdds[index];
4180 
4181 		query_attr[index + nattr_common].type =
4182 			KFD_IOCTL_SVM_ATTR_ACCESS;
4183 		query_attr[index + nattr_common].value = pdd->user_gpu_id;
4184 	}
4185 
4186 	svm_priv_data_size = sizeof(*svm_priv) + query_attr_size;
4187 
4188 	svm_priv = kzalloc(svm_priv_data_size, GFP_KERNEL);
4189 	if (!svm_priv) {
4190 		ret = -ENOMEM;
4191 		goto exit_query;
4192 	}
4193 
4194 	index = 0;
4195 	list_for_each_entry(prange, &svms->list, list) {
4196 
4197 		svm_priv->object_type = KFD_CRIU_OBJECT_TYPE_SVM_RANGE;
4198 		svm_priv->start_addr = prange->start;
4199 		svm_priv->size = prange->npages;
4200 		memcpy(&svm_priv->attrs, query_attr, query_attr_size);
4201 		pr_debug("CRIU: prange: 0x%p start: 0x%lx\t npages: 0x%llx end: 0x%llx\t size: 0x%llx\n",
4202 			 prange, prange->start, prange->npages,
4203 			 prange->start + prange->npages - 1,
4204 			 prange->npages * PAGE_SIZE);
4205 
4206 		ret = svm_range_get_attr(p, mm, svm_priv->start_addr,
4207 					 svm_priv->size,
4208 					 (nattr_common + num_devices),
4209 					 svm_priv->attrs);
4210 		if (ret) {
4211 			pr_err("CRIU: failed to obtain range attributes\n");
4212 			goto exit_priv;
4213 		}
4214 
4215 		if (copy_to_user(user_priv_data + *priv_data_offset, svm_priv,
4216 				 svm_priv_data_size)) {
4217 			pr_err("Failed to copy svm priv to user\n");
4218 			ret = -EFAULT;
4219 			goto exit_priv;
4220 		}
4221 
4222 		*priv_data_offset += svm_priv_data_size;
4223 
4224 	}
4225 
4226 
4227 exit_priv:
4228 	kfree(svm_priv);
4229 exit_query:
4230 	kfree(query_attr);
4231 exit:
4232 	mmput(mm);
4233 	return ret;
4234 }
4235 
4236 int
4237 svm_ioctl(struct kfd_process *p, enum kfd_ioctl_svm_op op, uint64_t start,
4238 	  uint64_t size, uint32_t nattrs, struct kfd_ioctl_svm_attribute *attrs)
4239 {
4240 	struct mm_struct *mm = current->mm;
4241 	int r;
4242 
4243 	start >>= PAGE_SHIFT;
4244 	size >>= PAGE_SHIFT;
4245 
4246 	switch (op) {
4247 	case KFD_IOCTL_SVM_OP_SET_ATTR:
4248 		r = svm_range_set_attr(p, mm, start, size, nattrs, attrs);
4249 		break;
4250 	case KFD_IOCTL_SVM_OP_GET_ATTR:
4251 		r = svm_range_get_attr(p, mm, start, size, nattrs, attrs);
4252 		break;
4253 	default:
4254 		r = EINVAL;
4255 		break;
4256 	}
4257 
4258 	return r;
4259 }
4260