xref: /linux/drivers/gpu/drm/amd/amdkfd/kfd_svm.c (revision 6ab4054fda924dabc88e78b13c76043d55d257e0)
1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /*
3  * Copyright 2020-2021 Advanced Micro Devices, Inc.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be included in
13  * all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
19  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
20  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
21  * OTHER DEALINGS IN THE SOFTWARE.
22  */
23 
24 #include <linux/types.h>
25 #include <linux/sched/task.h>
26 #include <linux/dynamic_debug.h>
27 #include <drm/ttm/ttm_tt.h>
28 #include <drm/drm_exec.h>
29 
30 #include "amdgpu_sync.h"
31 #include "amdgpu_object.h"
32 #include "amdgpu_vm.h"
33 #include "amdgpu_hmm.h"
34 #include "amdgpu.h"
35 #include "amdgpu_xgmi.h"
36 #include "amdgpu_reset.h"
37 #include "kfd_priv.h"
38 #include "kfd_svm.h"
39 #include "kfd_migrate.h"
40 #include "kfd_smi_events.h"
41 
42 #ifdef dev_fmt
43 #undef dev_fmt
44 #endif
45 #define dev_fmt(fmt) "kfd_svm: %s: " fmt, __func__
46 
47 #define AMDGPU_SVM_RANGE_RESTORE_DELAY_MS 1
48 
49 /* Long enough to ensure no retry fault comes after svm range is restored and
50  * page table is updated.
51  */
52 #define AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING	(2UL * NSEC_PER_MSEC)
53 #if IS_ENABLED(CONFIG_DYNAMIC_DEBUG)
54 #define dynamic_svm_range_dump(svms) \
55 	_dynamic_func_call_no_desc("svm_range_dump", svm_range_debug_dump, svms)
56 #else
57 #define dynamic_svm_range_dump(svms) \
58 	do { if (0) svm_range_debug_dump(svms); } while (0)
59 #endif
60 
61 /* Giant svm range split into smaller ranges based on this, it is decided using
62  * minimum of all dGPU/APU 1/32 VRAM size, between 2MB to 1GB and alignment to
63  * power of 2MB.
64  */
65 static uint64_t max_svm_range_pages;
66 
67 struct criu_svm_metadata {
68 	struct list_head list;
69 	struct kfd_criu_svm_range_priv_data data;
70 };
71 
72 static void svm_range_evict_svm_bo_worker(struct work_struct *work);
73 static bool
74 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
75 				    const struct mmu_notifier_range *range,
76 				    unsigned long cur_seq);
77 static int
78 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
79 		   uint64_t *bo_s, uint64_t *bo_l);
80 static const struct mmu_interval_notifier_ops svm_range_mn_ops = {
81 	.invalidate = svm_range_cpu_invalidate_pagetables,
82 };
83 
84 /**
85  * svm_range_unlink - unlink svm_range from lists and interval tree
86  * @prange: svm range structure to be removed
87  *
88  * Remove the svm_range from the svms and svm_bo lists and the svms
89  * interval tree.
90  *
91  * Context: The caller must hold svms->lock
92  */
93 static void svm_range_unlink(struct svm_range *prange)
94 {
95 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
96 		 prange, prange->start, prange->last);
97 
98 	if (prange->svm_bo) {
99 		spin_lock(&prange->svm_bo->list_lock);
100 		list_del(&prange->svm_bo_list);
101 		spin_unlock(&prange->svm_bo->list_lock);
102 	}
103 
104 	list_del(&prange->list);
105 	if (prange->it_node.start != 0 && prange->it_node.last != 0)
106 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
107 }
108 
109 static void
110 svm_range_add_notifier_locked(struct mm_struct *mm, struct svm_range *prange)
111 {
112 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
113 		 prange, prange->start, prange->last);
114 
115 	mmu_interval_notifier_insert_locked(&prange->notifier, mm,
116 				     prange->start << PAGE_SHIFT,
117 				     prange->npages << PAGE_SHIFT,
118 				     &svm_range_mn_ops);
119 }
120 
121 /**
122  * svm_range_add_to_svms - add svm range to svms
123  * @prange: svm range structure to be added
124  *
125  * Add the svm range to svms interval tree and link list
126  *
127  * Context: The caller must hold svms->lock
128  */
129 static void svm_range_add_to_svms(struct svm_range *prange)
130 {
131 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
132 		 prange, prange->start, prange->last);
133 
134 	list_move_tail(&prange->list, &prange->svms->list);
135 	prange->it_node.start = prange->start;
136 	prange->it_node.last = prange->last;
137 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
138 }
139 
140 static void svm_range_remove_notifier(struct svm_range *prange)
141 {
142 	pr_debug("remove notifier svms 0x%p prange 0x%p [0x%lx 0x%lx]\n",
143 		 prange->svms, prange,
144 		 prange->notifier.interval_tree.start >> PAGE_SHIFT,
145 		 prange->notifier.interval_tree.last >> PAGE_SHIFT);
146 
147 	if (prange->notifier.interval_tree.start != 0 &&
148 	    prange->notifier.interval_tree.last != 0)
149 		mmu_interval_notifier_remove(&prange->notifier);
150 }
151 
152 static bool
153 svm_is_valid_dma_mapping_addr(struct device *dev, dma_addr_t dma_addr)
154 {
155 	return dma_addr && !dma_mapping_error(dev, dma_addr) &&
156 	       !(dma_addr & SVM_RANGE_VRAM_DOMAIN);
157 }
158 
159 static int
160 svm_range_dma_map_dev(struct amdgpu_device *adev, struct svm_range *prange,
161 		      unsigned long offset, unsigned long npages,
162 		      unsigned long *hmm_pfns, uint32_t gpuidx)
163 {
164 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
165 	dma_addr_t *addr = prange->dma_addr[gpuidx];
166 	struct device *dev = adev->dev;
167 	struct page *page;
168 	int i, r;
169 
170 	if (!addr) {
171 		addr = kvzalloc_objs(*addr, prange->npages);
172 		if (!addr)
173 			return -ENOMEM;
174 		prange->dma_addr[gpuidx] = addr;
175 	}
176 
177 	addr += offset;
178 	for (i = 0; i < npages; i++) {
179 		if (svm_is_valid_dma_mapping_addr(dev, addr[i]))
180 			dma_unmap_page(dev, addr[i], PAGE_SIZE, dir);
181 
182 		page = hmm_pfn_to_page(hmm_pfns[i]);
183 		if (is_zone_device_page(page)) {
184 			struct amdgpu_device *bo_adev = prange->svm_bo->node->adev;
185 
186 			addr[i] = (hmm_pfns[i] << PAGE_SHIFT) +
187 				   bo_adev->vm_manager.vram_base_offset -
188 				   bo_adev->kfd.pgmap.range.start;
189 			addr[i] |= SVM_RANGE_VRAM_DOMAIN;
190 			pr_debug_ratelimited("vram address: 0x%llx\n", addr[i]);
191 			continue;
192 		}
193 		addr[i] = dma_map_page(dev, page, 0, PAGE_SIZE, dir);
194 		r = dma_mapping_error(dev, addr[i]);
195 		if (r) {
196 			dev_err(dev, "failed %d dma_map_page\n", r);
197 			return r;
198 		}
199 		pr_debug_ratelimited("dma mapping 0x%llx for page addr 0x%lx\n",
200 				     addr[i] >> PAGE_SHIFT, page_to_pfn(page));
201 	}
202 
203 	return 0;
204 }
205 
206 static int
207 svm_range_dma_map(struct svm_range *prange, unsigned long *bitmap,
208 		  unsigned long offset, unsigned long npages,
209 		  unsigned long *hmm_pfns)
210 {
211 	struct kfd_process *p;
212 	uint32_t gpuidx;
213 	int r;
214 
215 	p = container_of(prange->svms, struct kfd_process, svms);
216 
217 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
218 		struct kfd_process_device *pdd;
219 
220 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
221 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
222 		if (!pdd) {
223 			pr_debug("failed to find device idx %d\n", gpuidx);
224 			return -EINVAL;
225 		}
226 
227 		r = svm_range_dma_map_dev(pdd->dev->adev, prange, offset, npages,
228 					  hmm_pfns, gpuidx);
229 		if (r)
230 			break;
231 	}
232 
233 	return r;
234 }
235 
236 void svm_range_dma_unmap_dev(struct device *dev, dma_addr_t *dma_addr,
237 			 unsigned long offset, unsigned long npages)
238 {
239 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
240 	int i;
241 
242 	if (!dma_addr)
243 		return;
244 
245 	for (i = offset; i < offset + npages; i++) {
246 		if (!svm_is_valid_dma_mapping_addr(dev, dma_addr[i]))
247 			continue;
248 		pr_debug_ratelimited("unmap 0x%llx\n", dma_addr[i] >> PAGE_SHIFT);
249 		dma_unmap_page(dev, dma_addr[i], PAGE_SIZE, dir);
250 		dma_addr[i] = 0;
251 	}
252 }
253 
254 void svm_range_dma_unmap(struct svm_range *prange)
255 {
256 	struct kfd_process_device *pdd;
257 	dma_addr_t *dma_addr;
258 	struct device *dev;
259 	struct kfd_process *p;
260 	uint32_t gpuidx;
261 
262 	p = container_of(prange->svms, struct kfd_process, svms);
263 
264 	for (gpuidx = 0; gpuidx < MAX_GPU_INSTANCE; gpuidx++) {
265 		dma_addr = prange->dma_addr[gpuidx];
266 		if (!dma_addr)
267 			continue;
268 
269 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
270 		if (!pdd) {
271 			pr_debug("failed to find device idx %d\n", gpuidx);
272 			continue;
273 		}
274 		dev = &pdd->dev->adev->pdev->dev;
275 
276 		svm_range_dma_unmap_dev(dev, dma_addr, 0, prange->npages);
277 	}
278 }
279 
280 static void svm_range_free(struct svm_range *prange, bool do_unmap)
281 {
282 	uint64_t size = (prange->last - prange->start + 1) << PAGE_SHIFT;
283 	struct kfd_process *p = container_of(prange->svms, struct kfd_process, svms);
284 	uint32_t gpuidx;
285 
286 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms, prange,
287 		 prange->start, prange->last);
288 
289 	svm_range_vram_node_free(prange);
290 	if (do_unmap)
291 		svm_range_dma_unmap(prange);
292 
293 	if (do_unmap && !p->xnack_enabled) {
294 		pr_debug("unreserve prange 0x%p size: 0x%llx\n", prange, size);
295 		amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
296 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
297 	}
298 
299 	/* free dma_addr array for each gpu */
300 	for (gpuidx = 0; gpuidx < MAX_GPU_INSTANCE; gpuidx++) {
301 		if (prange->dma_addr[gpuidx]) {
302 			kvfree(prange->dma_addr[gpuidx]);
303 			prange->dma_addr[gpuidx] = NULL;
304 		}
305 	}
306 
307 	mutex_destroy(&prange->lock);
308 	mutex_destroy(&prange->migrate_mutex);
309 	kfree(prange);
310 }
311 
312 static void
313 svm_range_set_default_attributes(struct svm_range_list *svms, int32_t *location,
314 				 int32_t *prefetch_loc, uint8_t *granularity,
315 				 uint32_t *flags)
316 {
317 	*location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
318 	*prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
319 	*granularity = svms->default_granularity;
320 	*flags =
321 		KFD_IOCTL_SVM_FLAG_HOST_ACCESS | KFD_IOCTL_SVM_FLAG_COHERENT;
322 }
323 
324 static struct
325 svm_range *svm_range_new(struct svm_range_list *svms, uint64_t start,
326 			 uint64_t last, bool update_mem_usage)
327 {
328 	uint64_t size = last - start + 1;
329 	struct svm_range *prange;
330 	struct kfd_process *p;
331 
332 	prange = kzalloc_obj(*prange);
333 	if (!prange)
334 		return NULL;
335 
336 	p = container_of(svms, struct kfd_process, svms);
337 	if (!p->xnack_enabled && update_mem_usage &&
338 	    amdgpu_amdkfd_reserve_mem_limit(NULL, size << PAGE_SHIFT,
339 				    KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0)) {
340 		pr_info("SVM mapping failed, exceeds resident system memory limit\n");
341 		kfree(prange);
342 		return NULL;
343 	}
344 	prange->npages = size;
345 	prange->svms = svms;
346 	prange->start = start;
347 	prange->last = last;
348 	INIT_LIST_HEAD(&prange->list);
349 	INIT_LIST_HEAD(&prange->update_list);
350 	INIT_LIST_HEAD(&prange->svm_bo_list);
351 	INIT_LIST_HEAD(&prange->deferred_list);
352 	INIT_LIST_HEAD(&prange->child_list);
353 	atomic_set(&prange->invalid, 0);
354 	prange->validate_timestamp = 0;
355 	prange->vram_pages = 0;
356 	mutex_init(&prange->migrate_mutex);
357 	mutex_init(&prange->lock);
358 
359 	if (p->xnack_enabled)
360 		bitmap_copy(prange->bitmap_access, svms->bitmap_supported,
361 			    MAX_GPU_INSTANCE);
362 
363 	svm_range_set_default_attributes(svms, &prange->preferred_loc,
364 					 &prange->prefetch_loc,
365 					 &prange->granularity, &prange->flags);
366 
367 	pr_debug("svms 0x%p [0x%llx 0x%llx]\n", svms, start, last);
368 
369 	return prange;
370 }
371 
372 static bool svm_bo_ref_unless_zero(struct svm_range_bo *svm_bo)
373 {
374 	if (!svm_bo || !kref_get_unless_zero(&svm_bo->kref))
375 		return false;
376 
377 	return true;
378 }
379 
380 static void svm_range_bo_release(struct kref *kref)
381 {
382 	struct svm_range_bo *svm_bo;
383 
384 	svm_bo = container_of(kref, struct svm_range_bo, kref);
385 	pr_debug("svm_bo 0x%p\n", svm_bo);
386 
387 	spin_lock(&svm_bo->list_lock);
388 	while (!list_empty(&svm_bo->range_list)) {
389 		struct svm_range *prange =
390 				list_first_entry(&svm_bo->range_list,
391 						struct svm_range, svm_bo_list);
392 		/* list_del_init tells a concurrent svm_range_vram_node_new when
393 		 * it's safe to reuse the svm_bo pointer and svm_bo_list head.
394 		 */
395 		list_del_init(&prange->svm_bo_list);
396 		spin_unlock(&svm_bo->list_lock);
397 
398 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
399 			 prange->start, prange->last);
400 		mutex_lock(&prange->lock);
401 		prange->svm_bo = NULL;
402 		/* prange should not hold vram page now */
403 		WARN_ONCE(prange->actual_loc, "prange should not hold vram page");
404 		mutex_unlock(&prange->lock);
405 
406 		spin_lock(&svm_bo->list_lock);
407 	}
408 	spin_unlock(&svm_bo->list_lock);
409 
410 	if (mmget_not_zero(svm_bo->eviction_fence->mm)) {
411 		struct kfd_process_device *pdd;
412 		struct kfd_process *p;
413 		struct mm_struct *mm;
414 
415 		mm = svm_bo->eviction_fence->mm;
416 		/*
417 		 * The forked child process takes svm_bo device pages ref, svm_bo could be
418 		 * released after parent process is gone.
419 		 */
420 		p = kfd_lookup_process_by_mm(mm);
421 		if (p) {
422 			pdd = kfd_get_process_device_data(svm_bo->node, p);
423 			if (pdd)
424 				atomic64_sub(amdgpu_bo_size(svm_bo->bo), &pdd->vram_usage);
425 			kfd_unref_process(p);
426 		}
427 		mmput(mm);
428 	}
429 
430 	if (!dma_fence_is_signaled(&svm_bo->eviction_fence->base))
431 		/* We're not in the eviction worker. Signal the fence. */
432 		dma_fence_signal(&svm_bo->eviction_fence->base);
433 	dma_fence_put(&svm_bo->eviction_fence->base);
434 	amdgpu_bo_unref(&svm_bo->bo);
435 	kfree(svm_bo);
436 }
437 
438 static void svm_range_bo_wq_release(struct work_struct *work)
439 {
440 	struct svm_range_bo *svm_bo;
441 
442 	svm_bo = container_of(work, struct svm_range_bo, release_work);
443 	svm_range_bo_release(&svm_bo->kref);
444 }
445 
446 static void svm_range_bo_release_async(struct kref *kref)
447 {
448 	struct svm_range_bo *svm_bo;
449 
450 	svm_bo = container_of(kref, struct svm_range_bo, kref);
451 	pr_debug("svm_bo 0x%p\n", svm_bo);
452 	INIT_WORK(&svm_bo->release_work, svm_range_bo_wq_release);
453 	schedule_work(&svm_bo->release_work);
454 }
455 
456 void svm_range_bo_unref_async(struct svm_range_bo *svm_bo)
457 {
458 	kref_put(&svm_bo->kref, svm_range_bo_release_async);
459 }
460 
461 static void svm_range_bo_unref(struct svm_range_bo *svm_bo)
462 {
463 	if (svm_bo)
464 		kref_put(&svm_bo->kref, svm_range_bo_release);
465 }
466 
467 static bool
468 svm_range_validate_svm_bo(struct kfd_node *node, struct svm_range *prange)
469 {
470 	mutex_lock(&prange->lock);
471 	if (!prange->svm_bo) {
472 		mutex_unlock(&prange->lock);
473 		return false;
474 	}
475 	if (prange->ttm_res) {
476 		/* We still have a reference, all is well */
477 		mutex_unlock(&prange->lock);
478 		return true;
479 	}
480 	if (svm_bo_ref_unless_zero(prange->svm_bo)) {
481 		/*
482 		 * Migrate from GPU to GPU, remove range from source svm_bo->node
483 		 * range list, and return false to allocate svm_bo from destination
484 		 * node.
485 		 */
486 		if (prange->svm_bo->node != node) {
487 			mutex_unlock(&prange->lock);
488 
489 			spin_lock(&prange->svm_bo->list_lock);
490 			list_del_init(&prange->svm_bo_list);
491 			spin_unlock(&prange->svm_bo->list_lock);
492 
493 			svm_range_bo_unref(prange->svm_bo);
494 			return false;
495 		}
496 		if (READ_ONCE(prange->svm_bo->evicting)) {
497 			struct dma_fence *f;
498 			struct svm_range_bo *svm_bo;
499 			/* The BO is getting evicted,
500 			 * we need to get a new one
501 			 */
502 			mutex_unlock(&prange->lock);
503 			svm_bo = prange->svm_bo;
504 			f = dma_fence_get(&svm_bo->eviction_fence->base);
505 			svm_range_bo_unref(prange->svm_bo);
506 			/* wait for the fence to avoid long spin-loop
507 			 * at list_empty_careful
508 			 */
509 			dma_fence_wait(f, false);
510 			dma_fence_put(f);
511 		} else {
512 			/* The BO was still around and we got
513 			 * a new reference to it
514 			 */
515 			mutex_unlock(&prange->lock);
516 			pr_debug("reuse old bo svms 0x%p [0x%lx 0x%lx]\n",
517 				 prange->svms, prange->start, prange->last);
518 
519 			prange->ttm_res = prange->svm_bo->bo->tbo.resource;
520 			return true;
521 		}
522 
523 	} else {
524 		mutex_unlock(&prange->lock);
525 	}
526 
527 	/* We need a new svm_bo. Spin-loop to wait for concurrent
528 	 * svm_range_bo_release to finish removing this range from
529 	 * its range list and set prange->svm_bo to null. After this,
530 	 * it is safe to reuse the svm_bo pointer and svm_bo_list head.
531 	 */
532 	while (!list_empty_careful(&prange->svm_bo_list) || prange->svm_bo)
533 		cond_resched();
534 
535 	return false;
536 }
537 
538 static struct svm_range_bo *svm_range_bo_new(void)
539 {
540 	struct svm_range_bo *svm_bo;
541 
542 	svm_bo = kzalloc_obj(*svm_bo);
543 	if (!svm_bo)
544 		return NULL;
545 
546 	kref_init(&svm_bo->kref);
547 	INIT_LIST_HEAD(&svm_bo->range_list);
548 	spin_lock_init(&svm_bo->list_lock);
549 
550 	return svm_bo;
551 }
552 
553 int
554 svm_range_vram_node_new(struct kfd_node *node, struct svm_range *prange,
555 			bool clear)
556 {
557 	struct kfd_process_device *pdd;
558 	struct amdgpu_bo_param bp;
559 	struct svm_range_bo *svm_bo;
560 	struct amdgpu_bo_user *ubo;
561 	struct amdgpu_bo *bo;
562 	struct kfd_process *p;
563 	struct mm_struct *mm;
564 	int r;
565 
566 	p = container_of(prange->svms, struct kfd_process, svms);
567 	pr_debug("process pid: %d svms 0x%p [0x%lx 0x%lx]\n",
568 		 p->lead_thread->pid, prange->svms,
569 		 prange->start, prange->last);
570 
571 	if (svm_range_validate_svm_bo(node, prange))
572 		return 0;
573 
574 	svm_bo = svm_range_bo_new();
575 	if (!svm_bo) {
576 		pr_debug("failed to alloc svm bo\n");
577 		return -ENOMEM;
578 	}
579 	mm = get_task_mm(p->lead_thread);
580 	if (!mm) {
581 		pr_debug("failed to get mm\n");
582 		kfree(svm_bo);
583 		return -ESRCH;
584 	}
585 	svm_bo->node = node;
586 	svm_bo->eviction_fence =
587 		amdgpu_amdkfd_fence_create(dma_fence_context_alloc(1),
588 					   mm,
589 					   svm_bo, p->context_id);
590 	mmput(mm);
591 	INIT_WORK(&svm_bo->eviction_work, svm_range_evict_svm_bo_worker);
592 	svm_bo->evicting = 0;
593 	memset(&bp, 0, sizeof(bp));
594 	bp.size = prange->npages * PAGE_SIZE;
595 	bp.byte_align = PAGE_SIZE;
596 	bp.domain = AMDGPU_GEM_DOMAIN_VRAM;
597 	bp.flags = AMDGPU_GEM_CREATE_NO_CPU_ACCESS;
598 	bp.flags |= clear ? AMDGPU_GEM_CREATE_VRAM_CLEARED : 0;
599 	bp.flags |= AMDGPU_GEM_CREATE_DISCARDABLE;
600 	bp.type = ttm_bo_type_device;
601 	bp.resv = NULL;
602 	if (node->xcp)
603 		bp.xcp_id_plus1 = node->xcp->id + 1;
604 
605 	r = amdgpu_bo_create_user(node->adev, &bp, &ubo);
606 	if (r) {
607 		pr_debug("failed %d to create bo\n", r);
608 		goto create_bo_failed;
609 	}
610 	bo = &ubo->bo;
611 
612 	pr_debug("alloc bo at offset 0x%lx size 0x%lx on partition %d\n",
613 		 bo->tbo.resource->start << PAGE_SHIFT, bp.size,
614 		 bp.xcp_id_plus1 - 1);
615 
616 	r = amdgpu_bo_reserve(bo, true);
617 	if (r) {
618 		pr_debug("failed %d to reserve bo\n", r);
619 		goto reserve_bo_failed;
620 	}
621 
622 	if (clear) {
623 		r = amdgpu_bo_sync_wait(bo, AMDGPU_FENCE_OWNER_KFD, false);
624 		if (r) {
625 			pr_debug("failed %d to sync bo\n", r);
626 			amdgpu_bo_unreserve(bo);
627 			goto reserve_bo_failed;
628 		}
629 	}
630 
631 	r = dma_resv_reserve_fences(bo->tbo.base.resv, TTM_NUM_MOVE_FENCES);
632 	if (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 	unsigned long last_align_down = ALIGN_DOWN(prange->last, 512);
1148 	unsigned long start_align = ALIGN(prange->start, 512);
1149 	bool huge_page_mapping = last_align_down > start_align;
1150 	struct svm_range *tail = NULL;
1151 	int r;
1152 
1153 	r = svm_range_split(prange, prange->start, new_last, &tail);
1154 
1155 	if (r)
1156 		return r;
1157 
1158 	list_add(&tail->list, insert_list);
1159 
1160 	if (huge_page_mapping && tail->start > start_align &&
1161 	    tail->start < last_align_down && (!IS_ALIGNED(tail->start, 512)))
1162 		list_add(&tail->update_list, remap_list);
1163 
1164 	return 0;
1165 }
1166 
1167 static int
1168 svm_range_split_head(struct svm_range *prange, uint64_t new_start,
1169 		     struct list_head *insert_list, struct list_head *remap_list)
1170 {
1171 	unsigned long last_align_down = ALIGN_DOWN(prange->last, 512);
1172 	unsigned long start_align = ALIGN(prange->start, 512);
1173 	bool huge_page_mapping = last_align_down > start_align;
1174 	struct svm_range *head = NULL;
1175 	int r;
1176 
1177 	r = svm_range_split(prange, new_start, prange->last, &head);
1178 
1179 	if (r)
1180 		return r;
1181 
1182 	list_add(&head->list, insert_list);
1183 
1184 	if (huge_page_mapping && head->last + 1 > start_align &&
1185 	    head->last + 1 < last_align_down && (!IS_ALIGNED(head->last, 512)))
1186 		list_add(&head->update_list, remap_list);
1187 
1188 	return 0;
1189 }
1190 
1191 static void
1192 svm_range_add_child(struct svm_range *prange, struct svm_range *pchild, enum svm_work_list_ops op)
1193 {
1194 	pr_debug("add child 0x%p [0x%lx 0x%lx] to prange 0x%p child list %d\n",
1195 		 pchild, pchild->start, pchild->last, prange, op);
1196 
1197 	pchild->work_item.mm = NULL;
1198 	pchild->work_item.op = op;
1199 	list_add_tail(&pchild->child_list, &prange->child_list);
1200 }
1201 
1202 static bool
1203 svm_nodes_in_same_hive(struct kfd_node *node_a, struct kfd_node *node_b)
1204 {
1205 	return (node_a->adev == node_b->adev ||
1206 		amdgpu_xgmi_same_hive(node_a->adev, node_b->adev));
1207 }
1208 
1209 static uint64_t
1210 svm_range_get_pte_flags(struct kfd_node *node, struct amdgpu_vm *vm,
1211 			struct svm_range *prange, int domain)
1212 {
1213 	struct kfd_node *bo_node;
1214 	uint32_t flags = prange->flags;
1215 	uint32_t mapping_flags = 0;
1216 	uint32_t gc_ip_version = KFD_GC_VERSION(node);
1217 	uint64_t pte_flags;
1218 	bool snoop = (domain != SVM_RANGE_VRAM_DOMAIN);
1219 	bool coherent = flags & (KFD_IOCTL_SVM_FLAG_COHERENT | KFD_IOCTL_SVM_FLAG_EXT_COHERENT);
1220 	bool ext_coherent = flags & KFD_IOCTL_SVM_FLAG_EXT_COHERENT;
1221 	unsigned int mtype_local, mtype_remote;
1222 	bool is_aid_a1, is_local;
1223 
1224 	if (domain == SVM_RANGE_VRAM_DOMAIN)
1225 		bo_node = prange->svm_bo->node;
1226 
1227 	switch (gc_ip_version) {
1228 	case IP_VERSION(9, 4, 1):
1229 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1230 			if (bo_node == node) {
1231 				mapping_flags |= coherent ?
1232 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1233 			} else {
1234 				mapping_flags |= coherent ?
1235 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1236 				if (svm_nodes_in_same_hive(node, bo_node))
1237 					snoop = true;
1238 			}
1239 		} else {
1240 			mapping_flags |= coherent ?
1241 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1242 		}
1243 		break;
1244 	case IP_VERSION(9, 4, 2):
1245 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1246 			if (bo_node == node) {
1247 				mapping_flags |= coherent ?
1248 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1249 				if (node->adev->gmc.xgmi.connected_to_cpu)
1250 					snoop = true;
1251 			} else {
1252 				mapping_flags |= coherent ?
1253 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1254 				if (svm_nodes_in_same_hive(node, bo_node))
1255 					snoop = true;
1256 			}
1257 		} else {
1258 			mapping_flags |= coherent ?
1259 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1260 		}
1261 		break;
1262 	case IP_VERSION(9, 4, 3):
1263 	case IP_VERSION(9, 4, 4):
1264 	case IP_VERSION(9, 5, 0):
1265 		if (ext_coherent)
1266 			mtype_local = AMDGPU_VM_MTYPE_CC;
1267 		else
1268 			mtype_local = amdgpu_mtype_local == 1 ? AMDGPU_VM_MTYPE_NC :
1269 				amdgpu_mtype_local == 2 ? AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1270 		snoop = true;
1271 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1272 			/* local HBM region close to partition */
1273 			if (bo_node->adev == node->adev &&
1274 			    (!bo_node->xcp || !node->xcp || bo_node->xcp->mem_id == node->xcp->mem_id))
1275 				mapping_flags |= mtype_local;
1276 			/* local HBM region far from partition or remote XGMI GPU
1277 			 * with regular system scope coherence
1278 			 */
1279 			else if (svm_nodes_in_same_hive(bo_node, node) && !ext_coherent)
1280 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1281 			/* PCIe P2P on GPUs pre-9.5.0 */
1282 			else if (gc_ip_version < IP_VERSION(9, 5, 0) &&
1283 				 !svm_nodes_in_same_hive(bo_node, node))
1284 				mapping_flags |= AMDGPU_VM_MTYPE_UC;
1285 			/* Other remote memory */
1286 			else
1287 				mapping_flags |= ext_coherent ? AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1288 		/* system memory accessed by the APU */
1289 		} else if (node->adev->flags & AMD_IS_APU) {
1290 			/* On NUMA systems, locality is determined per-page
1291 			 * in amdgpu_gmc_override_vm_pte_flags
1292 			 */
1293 			if (num_possible_nodes() <= 1)
1294 				mapping_flags |= mtype_local;
1295 			else
1296 				mapping_flags |= ext_coherent ? AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1297 		/* system memory accessed by the dGPU */
1298 		} else {
1299 			if (gc_ip_version < IP_VERSION(9, 5, 0) || ext_coherent)
1300 				mapping_flags |= AMDGPU_VM_MTYPE_UC;
1301 			else
1302 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1303 		}
1304 		break;
1305 	case IP_VERSION(12, 0, 0):
1306 	case IP_VERSION(12, 0, 1):
1307 		mapping_flags |= AMDGPU_VM_MTYPE_NC;
1308 		break;
1309 	case IP_VERSION(12, 1, 0):
1310 		is_aid_a1 = (node->adev->rev_id & 0x10);
1311 		is_local = (domain == SVM_RANGE_VRAM_DOMAIN) &&
1312 				(bo_node->adev == node->adev);
1313 
1314 		mtype_local = amdgpu_mtype_local == 0 ? AMDGPU_VM_MTYPE_RW :
1315 				amdgpu_mtype_local == 1 ? AMDGPU_VM_MTYPE_NC :
1316 				is_aid_a1 ? AMDGPU_VM_MTYPE_RW : AMDGPU_VM_MTYPE_NC;
1317 		mtype_remote = is_aid_a1 ? AMDGPU_VM_MTYPE_NC : AMDGPU_VM_MTYPE_UC;
1318 		snoop = true;
1319 
1320 		if (is_local) /* local HBM  */ {
1321 			mapping_flags |= mtype_local;
1322 		} else if (ext_coherent) {
1323 			mapping_flags |= AMDGPU_VM_MTYPE_UC;
1324 		} else {
1325 			/* system memory or remote VRAM */
1326 			mapping_flags |= mtype_remote;
1327 		}
1328 		break;
1329 	default:
1330 		mapping_flags |= coherent ?
1331 			AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1332 	}
1333 
1334 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_EXEC)
1335 		mapping_flags |= AMDGPU_VM_PAGE_EXECUTABLE;
1336 
1337 	pte_flags = AMDGPU_PTE_VALID;
1338 	pte_flags |= (domain == SVM_RANGE_VRAM_DOMAIN) ? 0 : AMDGPU_PTE_SYSTEM;
1339 	pte_flags |= snoop ? AMDGPU_PTE_SNOOPED : 0;
1340 	if (gc_ip_version >= IP_VERSION(12, 0, 0))
1341 		pte_flags |= AMDGPU_PTE_IS_PTE;
1342 
1343 	amdgpu_gmc_get_vm_pte(node->adev, vm, NULL, mapping_flags, &pte_flags);
1344 	pte_flags |= AMDGPU_PTE_READABLE;
1345 	if (!(flags & KFD_IOCTL_SVM_FLAG_GPU_RO))
1346 		pte_flags |= AMDGPU_PTE_WRITEABLE;
1347 
1348 	if ((gc_ip_version == IP_VERSION(12, 1, 0)) &&
1349 	    node->adev->have_atomics_support)
1350 		pte_flags |= AMDGPU_PTE_BUS_ATOMICS;
1351 
1352 	return pte_flags;
1353 }
1354 
1355 static int
1356 svm_range_unmap_from_gpu(struct amdgpu_device *adev, struct amdgpu_vm *vm,
1357 			 uint64_t start, uint64_t last,
1358 			 struct dma_fence **fence)
1359 {
1360 	uint64_t init_pte_value = adev->gmc.init_pte_flags;
1361 	uint64_t gpu_start, gpu_end;
1362 
1363 	/* Convert CPU page range to GPU page range */
1364 	gpu_start = start * AMDGPU_GPU_PAGES_IN_CPU_PAGE;
1365 	gpu_end = (last + 1) * AMDGPU_GPU_PAGES_IN_CPU_PAGE - 1;
1366 
1367 	pr_debug("CPU[0x%llx 0x%llx] -> GPU[0x%llx 0x%llx]\n", start, last,
1368 		gpu_start, gpu_end);
1369 	return amdgpu_vm_update_range(adev, vm, false, true, true, false, NULL, gpu_start,
1370 				      gpu_end, init_pte_value, 0, 0, NULL, NULL,
1371 				      fence);
1372 }
1373 
1374 static int
1375 svm_range_unmap_from_gpus(struct svm_range *prange, unsigned long start,
1376 			  unsigned long last, uint32_t trigger)
1377 {
1378 	struct kfd_process_device *pdd;
1379 	struct dma_fence *fence = NULL;
1380 	struct kfd_process *p;
1381 	uint32_t gpuidx;
1382 	int r = 0;
1383 
1384 	if (!prange->mapped_to_gpu) {
1385 		pr_debug("prange 0x%p [0x%lx 0x%lx] not mapped to GPU\n",
1386 			 prange, prange->start, prange->last);
1387 		return 0;
1388 	}
1389 
1390 	if (prange->start == start && prange->last == last) {
1391 		pr_debug("unmap svms 0x%p prange 0x%p\n", prange->svms, prange);
1392 		prange->mapped_to_gpu = false;
1393 	}
1394 
1395 	p = container_of(prange->svms, struct kfd_process, svms);
1396 
1397 	for_each_or_bit(gpuidx, prange->bitmap_access, prange->bitmap_aip, MAX_GPU_INSTANCE) {
1398 		pr_debug("unmap from gpu idx 0x%x\n", gpuidx);
1399 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1400 		if (!pdd) {
1401 			pr_debug("failed to find device idx %d\n", gpuidx);
1402 			return -EINVAL;
1403 		}
1404 
1405 		kfd_smi_event_unmap_from_gpu(pdd->dev, p->lead_thread->pid,
1406 					     start, last, trigger);
1407 
1408 		r = svm_range_unmap_from_gpu(pdd->dev->adev,
1409 					     drm_priv_to_vm(pdd->drm_priv),
1410 					     start, last, &fence);
1411 		if (r)
1412 			break;
1413 
1414 		if (fence) {
1415 			r = dma_fence_wait(fence, false);
1416 			dma_fence_put(fence);
1417 			fence = NULL;
1418 			if (r)
1419 				break;
1420 		}
1421 		kfd_flush_tlb(pdd, TLB_FLUSH_HEAVYWEIGHT);
1422 	}
1423 
1424 	return r;
1425 }
1426 
1427 static int
1428 svm_range_map_to_gpu(struct kfd_process_device *pdd, struct svm_range *prange,
1429 		     unsigned long offset, unsigned long npages, bool readonly,
1430 		     dma_addr_t *dma_addr, struct amdgpu_device *bo_adev,
1431 		     struct dma_fence **fence, bool flush_tlb)
1432 {
1433 	struct amdgpu_device *adev = pdd->dev->adev;
1434 	struct amdgpu_vm *vm = drm_priv_to_vm(pdd->drm_priv);
1435 	uint64_t pte_flags;
1436 	unsigned long last_start;
1437 	int last_domain;
1438 	int r = 0;
1439 	int64_t i, j;
1440 
1441 	last_start = prange->start + offset;
1442 
1443 	pr_debug("svms 0x%p [0x%lx 0x%lx] readonly %d\n", prange->svms,
1444 		 last_start, last_start + npages - 1, readonly);
1445 
1446 	for (i = offset; i < offset + npages; i++) {
1447 		uint64_t gpu_start;
1448 		uint64_t gpu_end;
1449 
1450 		last_domain = dma_addr[i] & SVM_RANGE_VRAM_DOMAIN;
1451 		dma_addr[i] &= ~SVM_RANGE_VRAM_DOMAIN;
1452 
1453 		/* Collect all pages in the same address range and memory domain
1454 		 * that can be mapped with a single call to update mapping.
1455 		 */
1456 		if (i < offset + npages - 1 &&
1457 		    last_domain == (dma_addr[i + 1] & SVM_RANGE_VRAM_DOMAIN))
1458 			continue;
1459 
1460 		pr_debug("Mapping range [0x%lx 0x%llx] on domain: %s\n",
1461 			 last_start, prange->start + i, last_domain ? "GPU" : "CPU");
1462 
1463 		pte_flags = svm_range_get_pte_flags(pdd->dev, vm, prange, last_domain);
1464 		if (readonly)
1465 			pte_flags &= ~AMDGPU_PTE_WRITEABLE;
1466 
1467 
1468 		/* For dGPU mode, we use same vm_manager to allocate VRAM for
1469 		 * different memory partition based on fpfn/lpfn, we should use
1470 		 * same vm_manager.vram_base_offset regardless memory partition.
1471 		 */
1472 		gpu_start = last_start * AMDGPU_GPU_PAGES_IN_CPU_PAGE;
1473 		gpu_end = (prange->start + i + 1) * AMDGPU_GPU_PAGES_IN_CPU_PAGE - 1;
1474 
1475 		pr_debug("svms 0x%p map CPU[0x%lx 0x%llx] GPU[0x%llx 0x%llx] vram %d PTE 0x%llx\n",
1476 			 prange->svms, last_start, prange->start + i,
1477 			 gpu_start, gpu_end,
1478 			 (last_domain == SVM_RANGE_VRAM_DOMAIN) ? 1 : 0,
1479 			 pte_flags);
1480 
1481 		r = amdgpu_vm_update_range(adev, vm, false, false, flush_tlb, true,
1482 					   NULL, gpu_start, gpu_end,
1483 					   pte_flags,
1484 					   (last_start - prange->start) << PAGE_SHIFT,
1485 					   bo_adev ? bo_adev->vm_manager.vram_base_offset : 0,
1486 					   NULL, dma_addr, &vm->last_update);
1487 
1488 		for (j = last_start - prange->start; j <= i; j++)
1489 			dma_addr[j] |= last_domain;
1490 
1491 		if (r) {
1492 			pr_debug("failed %d to map to gpu 0x%lx\n", r, prange->start);
1493 			goto out;
1494 		}
1495 		last_start = prange->start + i + 1;
1496 	}
1497 
1498 	r = amdgpu_vm_update_pdes(adev, vm, false);
1499 	if (r) {
1500 		pr_debug("failed %d to update directories 0x%lx\n", r,
1501 			 prange->start);
1502 		goto out;
1503 	}
1504 
1505 	if (fence)
1506 		*fence = dma_fence_get(vm->last_update);
1507 
1508 out:
1509 	return r;
1510 }
1511 
1512 static int
1513 svm_range_map_to_gpus(struct svm_range *prange, unsigned long offset,
1514 		      unsigned long npages, bool readonly,
1515 		      unsigned long *bitmap, bool wait, bool flush_tlb)
1516 {
1517 	struct kfd_process_device *pdd;
1518 	struct amdgpu_device *bo_adev = NULL;
1519 	struct kfd_process *p;
1520 	struct dma_fence *fence = NULL;
1521 	uint32_t gpuidx;
1522 	int r = 0;
1523 
1524 	if (prange->svm_bo && prange->ttm_res)
1525 		bo_adev = prange->svm_bo->node->adev;
1526 
1527 	p = container_of(prange->svms, struct kfd_process, svms);
1528 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1529 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
1530 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1531 		if (!pdd) {
1532 			pr_debug("failed to find device idx %d\n", gpuidx);
1533 			return -EINVAL;
1534 		}
1535 
1536 		pdd = kfd_bind_process_to_device(pdd->dev, p);
1537 		if (IS_ERR(pdd))
1538 			return -EINVAL;
1539 
1540 		if (bo_adev && pdd->dev->adev != bo_adev &&
1541 		    !amdgpu_xgmi_same_hive(pdd->dev->adev, bo_adev)) {
1542 			pr_debug("cannot map to device idx %d\n", gpuidx);
1543 			continue;
1544 		}
1545 
1546 		r = svm_range_map_to_gpu(pdd, prange, offset, npages, readonly,
1547 					 prange->dma_addr[gpuidx],
1548 					 bo_adev, wait ? &fence : NULL,
1549 					 flush_tlb);
1550 		if (r)
1551 			break;
1552 
1553 		if (fence) {
1554 			r = dma_fence_wait(fence, false);
1555 			dma_fence_put(fence);
1556 			fence = NULL;
1557 			if (r) {
1558 				pr_debug("failed %d to dma fence wait\n", r);
1559 				break;
1560 			}
1561 		}
1562 
1563 		kfd_flush_tlb(pdd, TLB_FLUSH_LEGACY);
1564 	}
1565 
1566 	return r;
1567 }
1568 
1569 struct svm_validate_context {
1570 	struct kfd_process *process;
1571 	struct svm_range *prange;
1572 	bool intr;
1573 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1574 	struct drm_exec exec;
1575 };
1576 
1577 static int svm_range_reserve_bos(struct svm_validate_context *ctx, bool intr)
1578 {
1579 	struct kfd_process_device *pdd;
1580 	struct amdgpu_vm *vm;
1581 	uint32_t gpuidx;
1582 	int r;
1583 
1584 	drm_exec_init(&ctx->exec, intr ? DRM_EXEC_INTERRUPTIBLE_WAIT: 0, 0);
1585 	drm_exec_until_all_locked(&ctx->exec) {
1586 		for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1587 			pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1588 			if (!pdd) {
1589 				pr_debug("failed to find device idx %d\n", gpuidx);
1590 				r = -EINVAL;
1591 				goto unreserve_out;
1592 			}
1593 			vm = drm_priv_to_vm(pdd->drm_priv);
1594 
1595 			r = amdgpu_vm_lock_pd(vm, &ctx->exec, 2);
1596 			drm_exec_retry_on_contention(&ctx->exec);
1597 			if (unlikely(r)) {
1598 				pr_debug("failed %d to reserve bo\n", r);
1599 				goto unreserve_out;
1600 			}
1601 		}
1602 	}
1603 
1604 	for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1605 		pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1606 		if (!pdd) {
1607 			pr_debug("failed to find device idx %d\n", gpuidx);
1608 			r = -EINVAL;
1609 			goto unreserve_out;
1610 		}
1611 
1612 		r = amdgpu_vm_validate(pdd->dev->adev,
1613 				       drm_priv_to_vm(pdd->drm_priv), NULL,
1614 				       svm_range_bo_validate, NULL);
1615 		if (r) {
1616 			pr_debug("failed %d validate pt bos\n", r);
1617 			goto unreserve_out;
1618 		}
1619 	}
1620 
1621 	return 0;
1622 
1623 unreserve_out:
1624 	drm_exec_fini(&ctx->exec);
1625 	return r;
1626 }
1627 
1628 static void svm_range_unreserve_bos(struct svm_validate_context *ctx)
1629 {
1630 	drm_exec_fini(&ctx->exec);
1631 }
1632 
1633 static void *kfd_svm_page_owner(struct kfd_process *p, int32_t gpuidx)
1634 {
1635 	struct kfd_process_device *pdd;
1636 
1637 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1638 	if (!pdd)
1639 		return NULL;
1640 
1641 	return SVM_ADEV_PGMAP_OWNER(pdd->dev->adev);
1642 }
1643 
1644 /*
1645  * Validation+GPU mapping with concurrent invalidation (MMU notifiers)
1646  *
1647  * To prevent concurrent destruction or change of range attributes, the
1648  * svm_read_lock must be held. The caller must not hold the svm_write_lock
1649  * because that would block concurrent evictions and lead to deadlocks. To
1650  * serialize concurrent migrations or validations of the same range, the
1651  * prange->migrate_mutex must be held.
1652  *
1653  * For VRAM ranges, the SVM BO must be allocated and valid (protected by its
1654  * eviction fence.
1655  *
1656  * The following sequence ensures race-free validation and GPU mapping:
1657  *
1658  * 1. Reserve page table (and SVM BO if range is in VRAM)
1659  * 2. hmm_range_fault to get page addresses (if system memory)
1660  * 3. DMA-map pages (if system memory)
1661  * 4-a. Take notifier lock
1662  * 4-b. Check that pages still valid (mmu_interval_read_retry)
1663  * 4-c. Check that the range was not split or otherwise invalidated
1664  * 4-d. Update GPU page table
1665  * 4.e. Release notifier lock
1666  * 5. Release page table (and SVM BO) reservation
1667  */
1668 static int svm_range_validate_and_map(struct mm_struct *mm,
1669 				      unsigned long map_start, unsigned long map_last,
1670 				      struct svm_range *prange, int32_t gpuidx,
1671 				      bool intr, bool wait, bool flush_tlb)
1672 {
1673 	struct svm_validate_context *ctx;
1674 	unsigned long start, end, addr;
1675 	struct kfd_process *p;
1676 	void *owner;
1677 	int32_t idx;
1678 	int r = 0;
1679 
1680 	ctx = kzalloc_obj(struct svm_validate_context);
1681 	if (!ctx)
1682 		return -ENOMEM;
1683 	ctx->process = container_of(prange->svms, struct kfd_process, svms);
1684 	ctx->prange = prange;
1685 	ctx->intr = intr;
1686 
1687 	if (gpuidx < MAX_GPU_INSTANCE) {
1688 		bitmap_zero(ctx->bitmap, MAX_GPU_INSTANCE);
1689 		bitmap_set(ctx->bitmap, gpuidx, 1);
1690 	} else if (ctx->process->xnack_enabled) {
1691 		bitmap_copy(ctx->bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
1692 
1693 		/* If prefetch range to GPU, or GPU retry fault migrate range to
1694 		 * GPU, which has ACCESS attribute to the range, create mapping
1695 		 * on that GPU.
1696 		 */
1697 		if (prange->actual_loc) {
1698 			gpuidx = kfd_process_gpuidx_from_gpuid(ctx->process,
1699 							prange->actual_loc);
1700 			if (gpuidx < 0) {
1701 				WARN_ONCE(1, "failed get device by id 0x%x\n",
1702 					 prange->actual_loc);
1703 				r = -EINVAL;
1704 				goto free_ctx;
1705 			}
1706 			if (test_bit(gpuidx, prange->bitmap_access))
1707 				bitmap_set(ctx->bitmap, gpuidx, 1);
1708 		}
1709 
1710 		/*
1711 		 * If prange is already mapped or with always mapped flag,
1712 		 * update mapping on GPUs with ACCESS attribute
1713 		 */
1714 		if (bitmap_empty(ctx->bitmap, MAX_GPU_INSTANCE)) {
1715 			if (prange->mapped_to_gpu ||
1716 			    prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)
1717 				bitmap_copy(ctx->bitmap, prange->bitmap_access, MAX_GPU_INSTANCE);
1718 		}
1719 	} else {
1720 		bitmap_or(ctx->bitmap, prange->bitmap_access,
1721 			  prange->bitmap_aip, MAX_GPU_INSTANCE);
1722 	}
1723 
1724 	if (bitmap_empty(ctx->bitmap, MAX_GPU_INSTANCE)) {
1725 		r = 0;
1726 		goto free_ctx;
1727 	}
1728 
1729 	if (prange->actual_loc && !prange->ttm_res) {
1730 		/* This should never happen. actual_loc gets set by
1731 		 * svm_migrate_ram_to_vram after allocating a BO.
1732 		 */
1733 		WARN_ONCE(1, "VRAM BO missing during validation\n");
1734 		r = -EINVAL;
1735 		goto free_ctx;
1736 	}
1737 
1738 	r = svm_range_reserve_bos(ctx, intr);
1739 	if (r)
1740 		goto free_ctx;
1741 
1742 	p = container_of(prange->svms, struct kfd_process, svms);
1743 	owner = kfd_svm_page_owner(p, find_first_bit(ctx->bitmap,
1744 						MAX_GPU_INSTANCE));
1745 	for_each_set_bit(idx, ctx->bitmap, MAX_GPU_INSTANCE) {
1746 		if (kfd_svm_page_owner(p, idx) != owner) {
1747 			owner = NULL;
1748 			break;
1749 		}
1750 	}
1751 
1752 	start = map_start << PAGE_SHIFT;
1753 	end = (map_last + 1) << PAGE_SHIFT;
1754 	for (addr = start; !r && addr < end; ) {
1755 		struct amdgpu_hmm_range *range = NULL;
1756 		unsigned long map_start_vma;
1757 		unsigned long map_last_vma;
1758 		struct vm_area_struct *vma;
1759 		unsigned long next = 0;
1760 		unsigned long offset;
1761 		unsigned long npages;
1762 		bool readonly;
1763 
1764 		vma = vma_lookup(mm, addr);
1765 		if (vma) {
1766 			readonly = !(vma->vm_flags & VM_WRITE);
1767 
1768 			next = min(vma->vm_end, end);
1769 			npages = (next - addr) >> PAGE_SHIFT;
1770 			/* HMM requires at least READ permissions. If provided with PROT_NONE,
1771 			 * unmap the memory. If it's not already mapped, this is a no-op
1772 			 * If PROT_WRITE is provided without READ, warn first then unmap
1773 			 */
1774 			if (!(vma->vm_flags & VM_READ)) {
1775 				unsigned long e, s;
1776 
1777 				svm_range_lock(prange);
1778 				if (vma->vm_flags & VM_WRITE)
1779 					pr_debug("VM_WRITE without VM_READ is not supported");
1780 				s = max(start, prange->start);
1781 				e = min(end, prange->last);
1782 				if (e >= s)
1783 					r = svm_range_unmap_from_gpus(prange, s, e,
1784 						       KFD_SVM_UNMAP_TRIGGER_UNMAP_FROM_CPU);
1785 				svm_range_unlock(prange);
1786 				/* If unmap returns non-zero, we'll bail on the next for loop
1787 				 * iteration, so just leave r and continue
1788 				 */
1789 				addr = next;
1790 				continue;
1791 			}
1792 
1793 			WRITE_ONCE(p->svms.faulting_task, current);
1794 			range = amdgpu_hmm_range_alloc(NULL);
1795 			if (likely(range))
1796 				r = amdgpu_hmm_range_get_pages(&prange->notifier, addr, npages,
1797 							       readonly, owner, range);
1798 			else
1799 				r = -ENOMEM;
1800 			WRITE_ONCE(p->svms.faulting_task, NULL);
1801 			if (r)
1802 				pr_debug("failed %d to get svm range pages\n", r);
1803 		} else {
1804 			r = -EFAULT;
1805 		}
1806 
1807 		if (!r) {
1808 			offset = (addr >> PAGE_SHIFT) - prange->start;
1809 			r = svm_range_dma_map(prange, ctx->bitmap, offset, npages,
1810 					      range->hmm_range.hmm_pfns);
1811 			if (r)
1812 				pr_debug("failed %d to dma map range\n", r);
1813 		}
1814 
1815 		svm_range_lock(prange);
1816 
1817 		/* Free backing memory of hmm_range if it was initialized
1818 		 * Override return value to TRY AGAIN only if prior returns
1819 		 * were successful
1820 		 */
1821 		if (range && !amdgpu_hmm_range_valid(range) && !r) {
1822 			pr_debug("hmm update the range, need validate again\n");
1823 			r = -EAGAIN;
1824 		}
1825 
1826 		/* Free the hmm range */
1827 		amdgpu_hmm_range_free(range);
1828 
1829 		if (!r && !list_empty(&prange->child_list)) {
1830 			pr_debug("range split by unmap in parallel, validate again\n");
1831 			r = -EAGAIN;
1832 		}
1833 
1834 		if (!r) {
1835 			map_start_vma = max(map_start, prange->start + offset);
1836 			map_last_vma = min(map_last, prange->start + offset + npages - 1);
1837 			if (map_start_vma <= map_last_vma) {
1838 				offset = map_start_vma - prange->start;
1839 				npages = map_last_vma - map_start_vma + 1;
1840 				r = svm_range_map_to_gpus(prange, offset, npages, readonly,
1841 							  ctx->bitmap, wait, flush_tlb);
1842 			}
1843 		}
1844 
1845 		if (!r && next == end)
1846 			prange->mapped_to_gpu = true;
1847 
1848 		svm_range_unlock(prange);
1849 
1850 		addr = next;
1851 	}
1852 
1853 	svm_range_unreserve_bos(ctx);
1854 	if (!r)
1855 		prange->validate_timestamp = ktime_get_boottime();
1856 
1857 free_ctx:
1858 	kfree(ctx);
1859 
1860 	return r;
1861 }
1862 
1863 /**
1864  * svm_range_list_lock_and_flush_work - flush pending deferred work
1865  *
1866  * @svms: the svm range list
1867  * @mm: the mm structure
1868  *
1869  * Context: Returns with mmap write lock held, pending deferred work flushed
1870  *
1871  */
1872 void
1873 svm_range_list_lock_and_flush_work(struct svm_range_list *svms,
1874 				   struct mm_struct *mm)
1875 {
1876 retry_flush_work:
1877 	flush_work(&svms->deferred_list_work);
1878 	mmap_write_lock(mm);
1879 
1880 	if (list_empty(&svms->deferred_range_list))
1881 		return;
1882 	mmap_write_unlock(mm);
1883 	pr_debug("retry flush\n");
1884 	goto retry_flush_work;
1885 }
1886 
1887 static void svm_range_restore_work(struct work_struct *work)
1888 {
1889 	struct delayed_work *dwork = to_delayed_work(work);
1890 	struct amdkfd_process_info *process_info;
1891 	struct svm_range_list *svms;
1892 	struct svm_range *prange;
1893 	struct kfd_process *p;
1894 	struct mm_struct *mm;
1895 	int evicted_ranges;
1896 	int invalid;
1897 	int r;
1898 
1899 	svms = container_of(dwork, struct svm_range_list, restore_work);
1900 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1901 	if (!evicted_ranges)
1902 		return;
1903 
1904 	pr_debug("restore svm ranges\n");
1905 
1906 	p = container_of(svms, struct kfd_process, svms);
1907 	process_info = p->kgd_process_info;
1908 
1909 	/* Keep mm reference when svm_range_validate_and_map ranges */
1910 	mm = get_task_mm(p->lead_thread);
1911 	if (!mm) {
1912 		pr_debug("svms 0x%p process mm gone\n", svms);
1913 		return;
1914 	}
1915 
1916 	mutex_lock(&process_info->lock);
1917 	svm_range_list_lock_and_flush_work(svms, mm);
1918 	mutex_lock(&svms->lock);
1919 
1920 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1921 
1922 	list_for_each_entry(prange, &svms->list, list) {
1923 		invalid = atomic_read(&prange->invalid);
1924 		if (!invalid)
1925 			continue;
1926 
1927 		pr_debug("restoring svms 0x%p prange 0x%p [0x%lx %lx] inv %d\n",
1928 			 prange->svms, prange, prange->start, prange->last,
1929 			 invalid);
1930 
1931 		/*
1932 		 * If range is migrating, wait for migration is done.
1933 		 */
1934 		mutex_lock(&prange->migrate_mutex);
1935 
1936 		r = svm_range_validate_and_map(mm, prange->start, prange->last, prange,
1937 					       MAX_GPU_INSTANCE, false, true, false);
1938 		if (r)
1939 			pr_debug("failed %d to map 0x%lx to gpus\n", r,
1940 				 prange->start);
1941 
1942 		mutex_unlock(&prange->migrate_mutex);
1943 		if (r)
1944 			goto out_reschedule;
1945 
1946 		if (atomic_cmpxchg(&prange->invalid, invalid, 0) != invalid)
1947 			goto out_reschedule;
1948 	}
1949 
1950 	if (atomic_cmpxchg(&svms->evicted_ranges, evicted_ranges, 0) !=
1951 	    evicted_ranges)
1952 		goto out_reschedule;
1953 
1954 	evicted_ranges = 0;
1955 
1956 	r = kgd2kfd_resume_mm(mm);
1957 	if (r) {
1958 		/* No recovery from this failure. Probably the CP is
1959 		 * hanging. No point trying again.
1960 		 */
1961 		pr_debug("failed %d to resume KFD\n", r);
1962 	}
1963 
1964 	pr_debug("restore svm ranges successfully\n");
1965 
1966 out_reschedule:
1967 	mutex_unlock(&svms->lock);
1968 	mmap_write_unlock(mm);
1969 	mutex_unlock(&process_info->lock);
1970 
1971 	/* If validation failed, reschedule another attempt */
1972 	if (evicted_ranges) {
1973 		pr_debug("reschedule to restore svm range\n");
1974 		queue_delayed_work(system_freezable_wq, &svms->restore_work,
1975 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1976 
1977 		kfd_smi_event_queue_restore_rescheduled(mm);
1978 	}
1979 	mmput(mm);
1980 }
1981 
1982 /**
1983  * svm_range_evict - evict svm range
1984  * @prange: svm range structure
1985  * @mm: current process mm_struct
1986  * @start: starting process queue number
1987  * @last: last process queue number
1988  * @event: mmu notifier event when range is evicted or migrated
1989  *
1990  * Stop all queues of the process to ensure GPU doesn't access the memory, then
1991  * return to let CPU evict the buffer and proceed CPU pagetable update.
1992  *
1993  * Don't need use lock to sync cpu pagetable invalidation with GPU execution.
1994  * If invalidation happens while restore work is running, restore work will
1995  * restart to ensure to get the latest CPU pages mapping to GPU, then start
1996  * the queues.
1997  */
1998 static int
1999 svm_range_evict(struct svm_range *prange, struct mm_struct *mm,
2000 		unsigned long start, unsigned long last,
2001 		enum mmu_notifier_event event)
2002 {
2003 	struct svm_range_list *svms = prange->svms;
2004 	struct svm_range *pchild;
2005 	struct kfd_process *p;
2006 	int r = 0;
2007 
2008 	p = container_of(svms, struct kfd_process, svms);
2009 
2010 	pr_debug("invalidate svms 0x%p prange [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
2011 		 svms, prange->start, prange->last, start, last);
2012 
2013 	if (!p->xnack_enabled ||
2014 	    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) {
2015 		int evicted_ranges;
2016 		bool mapped = prange->mapped_to_gpu;
2017 
2018 		list_for_each_entry(pchild, &prange->child_list, child_list) {
2019 			if (!pchild->mapped_to_gpu)
2020 				continue;
2021 			mapped = true;
2022 			mutex_lock_nested(&pchild->lock, 1);
2023 			if (pchild->start <= last && pchild->last >= start) {
2024 				pr_debug("increment pchild invalid [0x%lx 0x%lx]\n",
2025 					 pchild->start, pchild->last);
2026 				atomic_inc(&pchild->invalid);
2027 			}
2028 			mutex_unlock(&pchild->lock);
2029 		}
2030 
2031 		if (!mapped)
2032 			return r;
2033 
2034 		if (prange->start <= last && prange->last >= start)
2035 			atomic_inc(&prange->invalid);
2036 
2037 		evicted_ranges = atomic_inc_return(&svms->evicted_ranges);
2038 		if (evicted_ranges != 1)
2039 			return r;
2040 
2041 		pr_debug("evicting svms 0x%p range [0x%lx 0x%lx]\n",
2042 			 prange->svms, prange->start, prange->last);
2043 
2044 		/* First eviction, stop the queues */
2045 		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_SVM);
2046 		if (r)
2047 			pr_debug("failed to quiesce KFD\n");
2048 
2049 		pr_debug("schedule to restore svm %p ranges\n", svms);
2050 		queue_delayed_work(system_freezable_wq, &svms->restore_work,
2051 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
2052 	} else {
2053 		unsigned long s, l;
2054 		uint32_t trigger;
2055 
2056 		if (event == MMU_NOTIFY_MIGRATE)
2057 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY_MIGRATE;
2058 		else
2059 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY;
2060 
2061 		pr_debug("invalidate unmap svms 0x%p [0x%lx 0x%lx] from GPUs\n",
2062 			 prange->svms, start, last);
2063 		list_for_each_entry(pchild, &prange->child_list, child_list) {
2064 			mutex_lock_nested(&pchild->lock, 1);
2065 			s = max(start, pchild->start);
2066 			l = min(last, pchild->last);
2067 			if (l >= s)
2068 				svm_range_unmap_from_gpus(pchild, s, l, trigger);
2069 			mutex_unlock(&pchild->lock);
2070 		}
2071 		s = max(start, prange->start);
2072 		l = min(last, prange->last);
2073 		if (l >= s)
2074 			svm_range_unmap_from_gpus(prange, s, l, trigger);
2075 	}
2076 
2077 	return r;
2078 }
2079 
2080 static struct svm_range *svm_range_clone(struct svm_range *old)
2081 {
2082 	struct svm_range *new;
2083 
2084 	new = svm_range_new(old->svms, old->start, old->last, false);
2085 	if (!new)
2086 		return NULL;
2087 	if (svm_range_copy_dma_addrs(new, old)) {
2088 		svm_range_free(new, false);
2089 		return NULL;
2090 	}
2091 	if (old->svm_bo) {
2092 		new->ttm_res = old->ttm_res;
2093 		new->offset = old->offset;
2094 		new->svm_bo = svm_range_bo_ref(old->svm_bo);
2095 		spin_lock(&new->svm_bo->list_lock);
2096 		list_add(&new->svm_bo_list, &new->svm_bo->range_list);
2097 		spin_unlock(&new->svm_bo->list_lock);
2098 	}
2099 	new->flags = old->flags;
2100 	new->preferred_loc = old->preferred_loc;
2101 	new->prefetch_loc = old->prefetch_loc;
2102 	new->actual_loc = old->actual_loc;
2103 	new->granularity = old->granularity;
2104 	new->mapped_to_gpu = old->mapped_to_gpu;
2105 	new->vram_pages = old->vram_pages;
2106 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
2107 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
2108 	atomic_set(&new->queue_refcount, atomic_read(&old->queue_refcount));
2109 
2110 	return new;
2111 }
2112 
2113 void svm_range_set_max_pages(struct amdgpu_device *adev)
2114 {
2115 	uint64_t max_pages;
2116 	uint64_t pages, _pages;
2117 	uint64_t min_pages = 0;
2118 	int i, id;
2119 
2120 	for (i = 0; i < adev->kfd.dev->num_nodes; i++) {
2121 		if (adev->kfd.dev->nodes[i]->xcp)
2122 			id = adev->kfd.dev->nodes[i]->xcp->id;
2123 		else
2124 			id = -1;
2125 		pages = KFD_XCP_MEMORY_SIZE(adev, id) >> 17;
2126 		pages = clamp(pages, 1ULL << 9, 1ULL << 18);
2127 		pages = rounddown_pow_of_two(pages);
2128 		min_pages = min_not_zero(min_pages, pages);
2129 	}
2130 
2131 	do {
2132 		max_pages = READ_ONCE(max_svm_range_pages);
2133 		_pages = min_not_zero(max_pages, min_pages);
2134 	} while (cmpxchg(&max_svm_range_pages, max_pages, _pages) != max_pages);
2135 }
2136 
2137 static int
2138 svm_range_split_new(struct svm_range_list *svms, uint64_t start, uint64_t last,
2139 		    uint64_t max_pages, struct list_head *insert_list,
2140 		    struct list_head *update_list)
2141 {
2142 	struct svm_range *prange;
2143 	uint64_t l;
2144 
2145 	pr_debug("max_svm_range_pages 0x%llx adding [0x%llx 0x%llx]\n",
2146 		 max_pages, start, last);
2147 
2148 	while (last >= start) {
2149 		l = min(last, ALIGN_DOWN(start + max_pages, max_pages) - 1);
2150 
2151 		prange = svm_range_new(svms, start, l, true);
2152 		if (!prange)
2153 			return -ENOMEM;
2154 		list_add(&prange->list, insert_list);
2155 		list_add(&prange->update_list, update_list);
2156 
2157 		start = l + 1;
2158 	}
2159 	return 0;
2160 }
2161 
2162 /**
2163  * svm_range_add - add svm range and handle overlap
2164  * @p: the range add to this process svms
2165  * @start: page size aligned
2166  * @size: page size aligned
2167  * @nattr: number of attributes
2168  * @attrs: array of attributes
2169  * @update_list: output, the ranges need validate and update GPU mapping
2170  * @insert_list: output, the ranges need insert to svms
2171  * @remove_list: output, the ranges are replaced and need remove from svms
2172  * @remap_list: output, remap unaligned svm ranges
2173  *
2174  * Check if the virtual address range has overlap with any existing ranges,
2175  * split partly overlapping ranges and add new ranges in the gaps. All changes
2176  * should be applied to the range_list and interval tree transactionally. If
2177  * any range split or allocation fails, the entire update fails. Therefore any
2178  * existing overlapping svm_ranges are cloned and the original svm_ranges left
2179  * unchanged.
2180  *
2181  * If the transaction succeeds, the caller can update and insert clones and
2182  * new ranges, then free the originals.
2183  *
2184  * Otherwise the caller can free the clones and new ranges, while the old
2185  * svm_ranges remain unchanged.
2186  *
2187  * Context: Process context, caller must hold svms->lock
2188  *
2189  * Return:
2190  * 0 - OK, otherwise error code
2191  */
2192 static int
2193 svm_range_add(struct kfd_process *p, uint64_t start, uint64_t size,
2194 	      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
2195 	      struct list_head *update_list, struct list_head *insert_list,
2196 	      struct list_head *remove_list, struct list_head *remap_list)
2197 {
2198 	unsigned long last = start + size - 1UL;
2199 	struct svm_range_list *svms = &p->svms;
2200 	struct interval_tree_node *node;
2201 	struct svm_range *prange;
2202 	struct svm_range *tmp;
2203 	struct list_head new_list;
2204 	int r = 0;
2205 
2206 	pr_debug("svms 0x%p [0x%llx 0x%lx]\n", &p->svms, start, last);
2207 
2208 	INIT_LIST_HEAD(update_list);
2209 	INIT_LIST_HEAD(insert_list);
2210 	INIT_LIST_HEAD(remove_list);
2211 	INIT_LIST_HEAD(&new_list);
2212 	INIT_LIST_HEAD(remap_list);
2213 
2214 	node = interval_tree_iter_first(&svms->objects, start, last);
2215 	while (node) {
2216 		struct interval_tree_node *next;
2217 		unsigned long next_start;
2218 
2219 		pr_debug("found overlap node [0x%lx 0x%lx]\n", node->start,
2220 			 node->last);
2221 
2222 		prange = container_of(node, struct svm_range, it_node);
2223 		next = interval_tree_iter_next(node, start, last);
2224 		next_start = min(node->last, last) + 1;
2225 
2226 		if (svm_range_is_same_attrs(p, prange, nattr, attrs) &&
2227 		    prange->mapped_to_gpu) {
2228 			/* nothing to do */
2229 		} else if (node->start < start || node->last > last) {
2230 			/* node intersects the update range and its attributes
2231 			 * will change. Clone and split it, apply updates only
2232 			 * to the overlapping part
2233 			 */
2234 			struct svm_range *old = prange;
2235 
2236 			prange = svm_range_clone(old);
2237 			if (!prange) {
2238 				r = -ENOMEM;
2239 				goto out;
2240 			}
2241 
2242 			list_add(&old->update_list, remove_list);
2243 			list_add(&prange->list, insert_list);
2244 			list_add(&prange->update_list, update_list);
2245 
2246 			if (node->start < start) {
2247 				pr_debug("change old range start\n");
2248 				r = svm_range_split_head(prange, start,
2249 							 insert_list, remap_list);
2250 				if (r)
2251 					goto out;
2252 			}
2253 			if (node->last > last) {
2254 				pr_debug("change old range last\n");
2255 				r = svm_range_split_tail(prange, last,
2256 							 insert_list, remap_list);
2257 				if (r)
2258 					goto out;
2259 			}
2260 		} else {
2261 			/* The node is contained within start..last,
2262 			 * just update it
2263 			 */
2264 			list_add(&prange->update_list, update_list);
2265 		}
2266 
2267 		/* insert a new node if needed */
2268 		if (node->start > start) {
2269 			r = svm_range_split_new(svms, start, node->start - 1,
2270 						READ_ONCE(max_svm_range_pages),
2271 						&new_list, update_list);
2272 			if (r)
2273 				goto out;
2274 		}
2275 
2276 		node = next;
2277 		start = next_start;
2278 	}
2279 
2280 	/* add a final range at the end if needed */
2281 	if (start <= last)
2282 		r = svm_range_split_new(svms, start, last,
2283 					READ_ONCE(max_svm_range_pages),
2284 					&new_list, update_list);
2285 
2286 out:
2287 	if (r) {
2288 		list_for_each_entry_safe(prange, tmp, insert_list, list)
2289 			svm_range_free(prange, false);
2290 		list_for_each_entry_safe(prange, tmp, &new_list, list)
2291 			svm_range_free(prange, true);
2292 	} else {
2293 		list_splice(&new_list, insert_list);
2294 	}
2295 
2296 	return r;
2297 }
2298 
2299 static void
2300 svm_range_update_notifier_and_interval_tree(struct mm_struct *mm,
2301 					    struct svm_range *prange)
2302 {
2303 	unsigned long start;
2304 	unsigned long last;
2305 
2306 	start = prange->notifier.interval_tree.start >> PAGE_SHIFT;
2307 	last = prange->notifier.interval_tree.last >> PAGE_SHIFT;
2308 
2309 	if (prange->start == start && prange->last == last)
2310 		return;
2311 
2312 	pr_debug("up notifier 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
2313 		  prange->svms, prange, start, last, prange->start,
2314 		  prange->last);
2315 
2316 	if (start != 0 && last != 0) {
2317 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
2318 		svm_range_remove_notifier(prange);
2319 	}
2320 	prange->it_node.start = prange->start;
2321 	prange->it_node.last = prange->last;
2322 
2323 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
2324 	svm_range_add_notifier_locked(mm, prange);
2325 }
2326 
2327 static void
2328 svm_range_handle_list_op(struct svm_range_list *svms, struct svm_range *prange,
2329 			 struct mm_struct *mm)
2330 {
2331 	switch (prange->work_item.op) {
2332 	case SVM_OP_NULL:
2333 		pr_debug("NULL OP 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2334 			 svms, prange, prange->start, prange->last);
2335 		break;
2336 	case SVM_OP_UNMAP_RANGE:
2337 		pr_debug("remove 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2338 			 svms, prange, prange->start, prange->last);
2339 		svm_range_unlink(prange);
2340 		svm_range_remove_notifier(prange);
2341 		svm_range_free(prange, true);
2342 		break;
2343 	case SVM_OP_UPDATE_RANGE_NOTIFIER:
2344 		pr_debug("update notifier 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2345 			 svms, prange, prange->start, prange->last);
2346 		svm_range_update_notifier_and_interval_tree(mm, prange);
2347 		break;
2348 	case SVM_OP_UPDATE_RANGE_NOTIFIER_AND_MAP:
2349 		pr_debug("update and map 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2350 			 svms, prange, prange->start, prange->last);
2351 		svm_range_update_notifier_and_interval_tree(mm, prange);
2352 		/* TODO: implement deferred validation and mapping */
2353 		break;
2354 	case SVM_OP_ADD_RANGE:
2355 		pr_debug("add 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms, prange,
2356 			 prange->start, prange->last);
2357 		svm_range_add_to_svms(prange);
2358 		svm_range_add_notifier_locked(mm, prange);
2359 		break;
2360 	case SVM_OP_ADD_RANGE_AND_MAP:
2361 		pr_debug("add and map 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms,
2362 			 prange, prange->start, prange->last);
2363 		svm_range_add_to_svms(prange);
2364 		svm_range_add_notifier_locked(mm, prange);
2365 		/* TODO: implement deferred validation and mapping */
2366 		break;
2367 	default:
2368 		WARN_ONCE(1, "Unknown prange 0x%p work op %d\n", prange,
2369 			 prange->work_item.op);
2370 	}
2371 }
2372 
2373 static void svm_range_drain_retry_fault(struct svm_range_list *svms)
2374 {
2375 	struct kfd_process_device *pdd;
2376 	struct kfd_process *p;
2377 	uint32_t i;
2378 
2379 	p = container_of(svms, struct kfd_process, svms);
2380 
2381 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2382 		pdd = p->pdds[i];
2383 		if (!pdd)
2384 			continue;
2385 
2386 		pr_debug("drain retry fault gpu %d svms %p\n", i, svms);
2387 
2388 		if (!down_read_trylock(&pdd->dev->adev->reset_domain->sem))
2389 			continue;
2390 
2391 		amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2392 				pdd->dev->adev->irq.retry_cam_enabled ?
2393 				&pdd->dev->adev->irq.ih :
2394 				&pdd->dev->adev->irq.ih1);
2395 
2396 		if (pdd->dev->adev->irq.retry_cam_enabled)
2397 			amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2398 				&pdd->dev->adev->irq.ih_soft);
2399 
2400 		up_read(&pdd->dev->adev->reset_domain->sem);
2401 
2402 		pr_debug("drain retry fault gpu %d svms 0x%p done\n", i, svms);
2403 	}
2404 }
2405 
2406 static void svm_range_deferred_list_work(struct work_struct *work)
2407 {
2408 	struct svm_range_list *svms;
2409 	struct svm_range *prange;
2410 	struct mm_struct *mm;
2411 
2412 	svms = container_of(work, struct svm_range_list, deferred_list_work);
2413 	pr_debug("enter svms 0x%p\n", svms);
2414 
2415 	spin_lock(&svms->deferred_list_lock);
2416 	while (!list_empty(&svms->deferred_range_list)) {
2417 		prange = list_first_entry(&svms->deferred_range_list,
2418 					  struct svm_range, deferred_list);
2419 		spin_unlock(&svms->deferred_list_lock);
2420 
2421 		pr_debug("prange 0x%p [0x%lx 0x%lx] op %d\n", prange,
2422 			 prange->start, prange->last, prange->work_item.op);
2423 
2424 		mm = prange->work_item.mm;
2425 
2426 		mmap_write_lock(mm);
2427 
2428 		/* Remove from deferred_list must be inside mmap write lock, for
2429 		 * two race cases:
2430 		 * 1. unmap_from_cpu may change work_item.op and add the range
2431 		 *    to deferred_list again, cause use after free bug.
2432 		 * 2. svm_range_list_lock_and_flush_work may hold mmap write
2433 		 *    lock and continue because deferred_list is empty, but
2434 		 *    deferred_list work is actually waiting for mmap lock.
2435 		 */
2436 		spin_lock(&svms->deferred_list_lock);
2437 		list_del_init(&prange->deferred_list);
2438 		spin_unlock(&svms->deferred_list_lock);
2439 
2440 		mutex_lock(&svms->lock);
2441 		mutex_lock(&prange->migrate_mutex);
2442 		while (!list_empty(&prange->child_list)) {
2443 			struct svm_range *pchild;
2444 
2445 			pchild = list_first_entry(&prange->child_list,
2446 						struct svm_range, child_list);
2447 			pr_debug("child prange 0x%p op %d\n", pchild,
2448 				 pchild->work_item.op);
2449 			list_del_init(&pchild->child_list);
2450 			svm_range_handle_list_op(svms, pchild, mm);
2451 		}
2452 		mutex_unlock(&prange->migrate_mutex);
2453 
2454 		svm_range_handle_list_op(svms, prange, mm);
2455 		mutex_unlock(&svms->lock);
2456 		mmap_write_unlock(mm);
2457 
2458 		/* Pairs with mmget in svm_range_add_list_work. If dropping the
2459 		 * last mm refcount, schedule release work to avoid circular locking
2460 		 */
2461 		mmput_async(mm);
2462 
2463 		spin_lock(&svms->deferred_list_lock);
2464 	}
2465 	spin_unlock(&svms->deferred_list_lock);
2466 	pr_debug("exit svms 0x%p\n", svms);
2467 }
2468 
2469 void
2470 svm_range_add_list_work(struct svm_range_list *svms, struct svm_range *prange,
2471 			struct mm_struct *mm, enum svm_work_list_ops op)
2472 {
2473 	spin_lock(&svms->deferred_list_lock);
2474 	/* if prange is on the deferred list */
2475 	if (!list_empty(&prange->deferred_list)) {
2476 		pr_debug("update exist prange 0x%p work op %d\n", prange, op);
2477 		WARN_ONCE(prange->work_item.mm != mm, "unmatch mm\n");
2478 		if (op != SVM_OP_NULL &&
2479 		    prange->work_item.op != SVM_OP_UNMAP_RANGE)
2480 			prange->work_item.op = op;
2481 	} else {
2482 		/* Pairs with mmput in deferred_list_work.
2483 		 * If process is exiting and mm is gone, don't update mmu notifier.
2484 		 */
2485 		if (mmget_not_zero(mm)) {
2486 			prange->work_item.mm = mm;
2487 			prange->work_item.op = op;
2488 			list_add_tail(&prange->deferred_list,
2489 				      &prange->svms->deferred_range_list);
2490 			pr_debug("add prange 0x%p [0x%lx 0x%lx] to work list op %d\n",
2491 				 prange, prange->start, prange->last, op);
2492 		}
2493 	}
2494 	spin_unlock(&svms->deferred_list_lock);
2495 }
2496 
2497 void schedule_deferred_list_work(struct svm_range_list *svms)
2498 {
2499 	spin_lock(&svms->deferred_list_lock);
2500 	if (!list_empty(&svms->deferred_range_list))
2501 		schedule_work(&svms->deferred_list_work);
2502 	spin_unlock(&svms->deferred_list_lock);
2503 }
2504 
2505 static void
2506 svm_range_unmap_split(struct svm_range *parent, struct svm_range *prange, unsigned long start,
2507 		      unsigned long last)
2508 {
2509 	struct svm_range *head;
2510 	struct svm_range *tail;
2511 
2512 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2513 		pr_debug("prange 0x%p [0x%lx 0x%lx] is already freed\n", prange,
2514 			 prange->start, prange->last);
2515 		return;
2516 	}
2517 	if (start > prange->last || last < prange->start)
2518 		return;
2519 
2520 	head = tail = prange;
2521 	if (start > prange->start)
2522 		svm_range_split(prange, prange->start, start - 1, &tail);
2523 	if (last < tail->last)
2524 		svm_range_split(tail, last + 1, tail->last, &head);
2525 
2526 	if (head != prange && tail != prange) {
2527 		svm_range_add_child(parent, head, SVM_OP_UNMAP_RANGE);
2528 		svm_range_add_child(parent, tail, SVM_OP_ADD_RANGE);
2529 	} else if (tail != prange) {
2530 		svm_range_add_child(parent, tail, SVM_OP_UNMAP_RANGE);
2531 	} else if (head != prange) {
2532 		svm_range_add_child(parent, head, SVM_OP_UNMAP_RANGE);
2533 	} else if (parent != prange) {
2534 		prange->work_item.op = SVM_OP_UNMAP_RANGE;
2535 	}
2536 }
2537 
2538 static void
2539 svm_range_unmap_from_cpu(struct mm_struct *mm, struct svm_range *prange,
2540 			 unsigned long start, unsigned long last)
2541 {
2542 	uint32_t trigger = KFD_SVM_UNMAP_TRIGGER_UNMAP_FROM_CPU;
2543 	struct svm_range_list *svms;
2544 	struct svm_range *pchild;
2545 	struct kfd_process *p;
2546 	unsigned long s, l;
2547 	bool unmap_parent;
2548 	uint32_t i;
2549 
2550 	if (atomic_read(&prange->queue_refcount)) {
2551 		int r;
2552 
2553 		pr_warn("Freeing queue vital buffer 0x%lx, queue evicted\n",
2554 			prange->start << PAGE_SHIFT);
2555 		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_SVM);
2556 		if (r)
2557 			pr_debug("failed %d to quiesce KFD queues\n", r);
2558 	}
2559 
2560 	p = kfd_lookup_process_by_mm(mm);
2561 	if (!p)
2562 		return;
2563 	svms = &p->svms;
2564 
2565 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n", svms,
2566 		 prange, prange->start, prange->last, start, last);
2567 
2568 	/* calculate time stamps that are used to decide which page faults need be
2569 	 * dropped or handled before unmap pages from gpu vm
2570 	 */
2571 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2572 		struct kfd_process_device *pdd;
2573 		struct amdgpu_device *adev;
2574 		struct amdgpu_ih_ring *ih;
2575 		uint32_t checkpoint_wptr;
2576 
2577 		pdd = p->pdds[i];
2578 		if (!pdd)
2579 			continue;
2580 
2581 		adev = pdd->dev->adev;
2582 
2583 		/* Check and drain ih1 ring if cam not available */
2584 		if (!adev->irq.retry_cam_enabled && adev->irq.ih1.ring_size) {
2585 			ih = &adev->irq.ih1;
2586 			checkpoint_wptr = amdgpu_ih_get_wptr(adev, ih);
2587 			if (ih->rptr != checkpoint_wptr) {
2588 				svms->checkpoint_ts[i] =
2589 					amdgpu_ih_decode_iv_ts(adev, ih, checkpoint_wptr, -1);
2590 				continue;
2591 			}
2592 		}
2593 
2594 		/* check if dev->irq.ih_soft is not empty */
2595 		ih = &adev->irq.ih_soft;
2596 		checkpoint_wptr = amdgpu_ih_get_wptr(adev, ih);
2597 		if (ih->rptr != checkpoint_wptr)
2598 			svms->checkpoint_ts[i] = amdgpu_ih_decode_iv_ts(adev, ih, checkpoint_wptr, -1);
2599 	}
2600 
2601 	unmap_parent = start <= prange->start && last >= prange->last;
2602 
2603 	list_for_each_entry(pchild, &prange->child_list, child_list) {
2604 		mutex_lock_nested(&pchild->lock, 1);
2605 		s = max(start, pchild->start);
2606 		l = min(last, pchild->last);
2607 		if (l >= s)
2608 			svm_range_unmap_from_gpus(pchild, s, l, trigger);
2609 		svm_range_unmap_split(prange, pchild, start, last);
2610 		mutex_unlock(&pchild->lock);
2611 	}
2612 	s = max(start, prange->start);
2613 	l = min(last, prange->last);
2614 	if (l >= s)
2615 		svm_range_unmap_from_gpus(prange, s, l, trigger);
2616 	svm_range_unmap_split(prange, prange, start, last);
2617 
2618 	if (unmap_parent)
2619 		svm_range_add_list_work(svms, prange, mm, SVM_OP_UNMAP_RANGE);
2620 	else
2621 		svm_range_add_list_work(svms, prange, mm,
2622 					SVM_OP_UPDATE_RANGE_NOTIFIER);
2623 	schedule_deferred_list_work(svms);
2624 
2625 	kfd_unref_process(p);
2626 }
2627 
2628 /**
2629  * svm_range_cpu_invalidate_pagetables - interval notifier callback
2630  * @mni: mmu_interval_notifier struct
2631  * @range: mmu_notifier_range struct
2632  * @cur_seq: value to pass to mmu_interval_set_seq()
2633  *
2634  * If event is MMU_NOTIFY_UNMAP, this is from CPU unmap range, otherwise, it
2635  * is from migration, or CPU page invalidation callback.
2636  *
2637  * For unmap event, unmap range from GPUs, remove prange from svms in a delayed
2638  * work thread, and split prange if only part of prange is unmapped.
2639  *
2640  * For invalidation event, if GPU retry fault is not enabled, evict the queues,
2641  * then schedule svm_range_restore_work to update GPU mapping and resume queues.
2642  * If GPU retry fault is enabled, unmap the svm range from GPU, retry fault will
2643  * update GPU mapping to recover.
2644  *
2645  * Context: mmap lock, notifier_invalidate_start lock are held
2646  *          for invalidate event, prange lock is held if this is from migration
2647  */
2648 static bool
2649 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
2650 				    const struct mmu_notifier_range *range,
2651 				    unsigned long cur_seq)
2652 {
2653 	struct svm_range *prange;
2654 	unsigned long start;
2655 	unsigned long last;
2656 
2657 	if (range->event == MMU_NOTIFY_RELEASE)
2658 		return true;
2659 
2660 	start = mni->interval_tree.start;
2661 	last = mni->interval_tree.last;
2662 	start = max(start, range->start) >> PAGE_SHIFT;
2663 	last = min(last, range->end - 1) >> PAGE_SHIFT;
2664 	pr_debug("[0x%lx 0x%lx] range[0x%lx 0x%lx] notifier[0x%lx 0x%lx] %d\n",
2665 		 start, last, range->start >> PAGE_SHIFT,
2666 		 (range->end - 1) >> PAGE_SHIFT,
2667 		 mni->interval_tree.start >> PAGE_SHIFT,
2668 		 mni->interval_tree.last >> PAGE_SHIFT, range->event);
2669 
2670 	prange = container_of(mni, struct svm_range, notifier);
2671 
2672 	svm_range_lock(prange);
2673 	mmu_interval_set_seq(mni, cur_seq);
2674 
2675 	switch (range->event) {
2676 	case MMU_NOTIFY_UNMAP:
2677 		svm_range_unmap_from_cpu(mni->mm, prange, start, last);
2678 		break;
2679 	default:
2680 		svm_range_evict(prange, mni->mm, start, last, range->event);
2681 		break;
2682 	}
2683 
2684 	svm_range_unlock(prange);
2685 
2686 	return true;
2687 }
2688 
2689 /**
2690  * svm_range_from_addr - find svm range from fault address
2691  * @svms: svm range list header
2692  * @addr: address to search range interval tree, in pages
2693  * @parent: parent range if range is on child list
2694  *
2695  * Context: The caller must hold svms->lock
2696  *
2697  * Return: the svm_range found or NULL
2698  */
2699 struct svm_range *
2700 svm_range_from_addr(struct svm_range_list *svms, unsigned long addr,
2701 		    struct svm_range **parent)
2702 {
2703 	struct interval_tree_node *node;
2704 	struct svm_range *prange;
2705 	struct svm_range *pchild;
2706 
2707 	node = interval_tree_iter_first(&svms->objects, addr, addr);
2708 	if (!node)
2709 		return NULL;
2710 
2711 	prange = container_of(node, struct svm_range, it_node);
2712 	pr_debug("address 0x%lx prange [0x%lx 0x%lx] node [0x%lx 0x%lx]\n",
2713 		 addr, prange->start, prange->last, node->start, node->last);
2714 
2715 	if (addr >= prange->start && addr <= prange->last) {
2716 		if (parent)
2717 			*parent = prange;
2718 		return prange;
2719 	}
2720 	list_for_each_entry(pchild, &prange->child_list, child_list)
2721 		if (addr >= pchild->start && addr <= pchild->last) {
2722 			pr_debug("found address 0x%lx pchild [0x%lx 0x%lx]\n",
2723 				 addr, pchild->start, pchild->last);
2724 			if (parent)
2725 				*parent = prange;
2726 			return pchild;
2727 		}
2728 
2729 	return NULL;
2730 }
2731 
2732 /* svm_range_best_restore_location - decide the best fault restore location
2733  * @prange: svm range structure
2734  * @adev: the GPU on which vm fault happened
2735  *
2736  * This is only called when xnack is on, to decide the best location to restore
2737  * the range mapping after GPU vm fault. Caller uses the best location to do
2738  * migration if actual loc is not best location, then update GPU page table
2739  * mapping to the best location.
2740  *
2741  * If the preferred loc is accessible by faulting GPU, use preferred loc.
2742  * If vm fault gpu idx is on range ACCESSIBLE bitmap, best_loc is vm fault gpu
2743  * If vm fault gpu idx is on range ACCESSIBLE_IN_PLACE bitmap, then
2744  *    if range actual loc is cpu, best_loc is cpu
2745  *    if vm fault gpu is on xgmi same hive of range actual loc gpu, best_loc is
2746  *    range actual loc.
2747  * Otherwise, GPU no access, best_loc is -1.
2748  *
2749  * Return:
2750  * -1 means vm fault GPU no access
2751  * 0 for CPU or GPU id
2752  */
2753 static int32_t
2754 svm_range_best_restore_location(struct svm_range *prange,
2755 				struct kfd_node *node,
2756 				int32_t *gpuidx)
2757 {
2758 	struct kfd_node *bo_node, *preferred_node;
2759 	struct kfd_process *p;
2760 	uint32_t gpuid;
2761 	int r;
2762 
2763 	p = container_of(prange->svms, struct kfd_process, svms);
2764 
2765 	r = kfd_process_gpuid_from_node(p, node, &gpuid, gpuidx);
2766 	if (r < 0) {
2767 		pr_debug("failed to get gpuid from kgd\n");
2768 		return -1;
2769 	}
2770 
2771 	if (node->adev->apu_prefer_gtt)
2772 		return 0;
2773 
2774 	if (prange->preferred_loc == gpuid ||
2775 	    prange->preferred_loc == KFD_IOCTL_SVM_LOCATION_SYSMEM) {
2776 		return prange->preferred_loc;
2777 	} else if (prange->preferred_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
2778 		preferred_node = svm_range_get_node_by_id(prange, prange->preferred_loc);
2779 		if (preferred_node && svm_nodes_in_same_hive(node, preferred_node))
2780 			return prange->preferred_loc;
2781 		/* fall through */
2782 	}
2783 
2784 	if (test_bit(*gpuidx, prange->bitmap_access))
2785 		return gpuid;
2786 
2787 	if (test_bit(*gpuidx, prange->bitmap_aip)) {
2788 		if (!prange->actual_loc)
2789 			return 0;
2790 
2791 		bo_node = svm_range_get_node_by_id(prange, prange->actual_loc);
2792 		if (bo_node && svm_nodes_in_same_hive(node, bo_node))
2793 			return prange->actual_loc;
2794 		else
2795 			return 0;
2796 	}
2797 
2798 	return -1;
2799 }
2800 
2801 static int
2802 svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
2803 			       unsigned long *start, unsigned long *last,
2804 			       bool *is_heap_stack)
2805 {
2806 	struct vm_area_struct *vma;
2807 	struct interval_tree_node *node;
2808 	struct rb_node *rb_node;
2809 	unsigned long start_limit, end_limit;
2810 
2811 	vma = vma_lookup(p->mm, addr << PAGE_SHIFT);
2812 	if (!vma) {
2813 		pr_debug("VMA does not exist in address [0x%llx]\n", addr);
2814 		return -EFAULT;
2815 	}
2816 
2817 	*is_heap_stack = vma_is_initial_heap(vma) || vma_is_initial_stack(vma);
2818 
2819 	start_limit = max(vma->vm_start >> PAGE_SHIFT,
2820 		      (unsigned long)ALIGN_DOWN(addr, 1UL << p->svms.default_granularity));
2821 	end_limit = min(vma->vm_end >> PAGE_SHIFT,
2822 		    (unsigned long)ALIGN(addr + 1, 1UL << p->svms.default_granularity));
2823 
2824 	/* First range that starts after the fault address */
2825 	node = interval_tree_iter_first(&p->svms.objects, addr + 1, ULONG_MAX);
2826 	if (node) {
2827 		end_limit = min(end_limit, node->start);
2828 		/* Last range that ends before the fault address */
2829 		rb_node = rb_prev(&node->rb);
2830 	} else {
2831 		/* Last range must end before addr because
2832 		 * there was no range after addr
2833 		 */
2834 		rb_node = rb_last(&p->svms.objects.rb_root);
2835 	}
2836 	if (rb_node) {
2837 		node = container_of(rb_node, struct interval_tree_node, rb);
2838 		if (node->last >= addr) {
2839 			WARN(1, "Overlap with prev node and page fault addr\n");
2840 			return -EFAULT;
2841 		}
2842 		start_limit = max(start_limit, node->last + 1);
2843 	}
2844 
2845 	*start = start_limit;
2846 	*last = end_limit - 1;
2847 
2848 	pr_debug("vma [0x%lx 0x%lx] range [0x%lx 0x%lx] is_heap_stack %d\n",
2849 		 vma->vm_start >> PAGE_SHIFT, vma->vm_end >> PAGE_SHIFT,
2850 		 *start, *last, *is_heap_stack);
2851 
2852 	return 0;
2853 }
2854 
2855 static int
2856 svm_range_check_vm_userptr(struct kfd_process *p, uint64_t start, uint64_t last,
2857 			   uint64_t *bo_s, uint64_t *bo_l)
2858 {
2859 	struct amdgpu_bo_va_mapping *mapping;
2860 	struct interval_tree_node *node;
2861 	struct amdgpu_bo *bo = NULL;
2862 	unsigned long userptr;
2863 	uint32_t i;
2864 	int r;
2865 
2866 	for (i = 0; i < p->n_pdds; i++) {
2867 		struct amdgpu_vm *vm;
2868 
2869 		if (!p->pdds[i]->drm_priv)
2870 			continue;
2871 
2872 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
2873 		r = amdgpu_bo_reserve(vm->root.bo, false);
2874 		if (r)
2875 			return r;
2876 
2877 		/* Check userptr by searching entire vm->va interval tree */
2878 		node = interval_tree_iter_first(&vm->va, 0, ~0ULL);
2879 		while (node) {
2880 			mapping = container_of((struct rb_node *)node,
2881 					       struct amdgpu_bo_va_mapping, rb);
2882 			bo = mapping->bo_va->base.bo;
2883 
2884 			if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm,
2885 							 start << PAGE_SHIFT,
2886 							 last << PAGE_SHIFT,
2887 							 &userptr)) {
2888 				node = interval_tree_iter_next(node, 0, ~0ULL);
2889 				continue;
2890 			}
2891 
2892 			pr_debug("[0x%llx 0x%llx] already userptr mapped\n",
2893 				 start, last);
2894 			if (bo_s && bo_l) {
2895 				*bo_s = userptr >> PAGE_SHIFT;
2896 				*bo_l = *bo_s + bo->tbo.ttm->num_pages - 1;
2897 			}
2898 			amdgpu_bo_unreserve(vm->root.bo);
2899 			return -EADDRINUSE;
2900 		}
2901 		amdgpu_bo_unreserve(vm->root.bo);
2902 	}
2903 	return 0;
2904 }
2905 
2906 static struct
2907 svm_range *svm_range_create_unregistered_range(struct kfd_node *node,
2908 						struct kfd_process *p,
2909 						struct mm_struct *mm,
2910 						int64_t addr)
2911 {
2912 	struct svm_range *prange = NULL;
2913 	unsigned long start, last;
2914 	uint32_t gpuid, gpuidx;
2915 	bool is_heap_stack;
2916 	uint64_t bo_s = 0;
2917 	uint64_t bo_l = 0;
2918 	int r;
2919 
2920 	if (svm_range_get_range_boundaries(p, addr, &start, &last,
2921 					   &is_heap_stack))
2922 		return NULL;
2923 
2924 	r = svm_range_check_vm(p, start, last, &bo_s, &bo_l);
2925 	if (r != -EADDRINUSE)
2926 		r = svm_range_check_vm_userptr(p, start, last, &bo_s, &bo_l);
2927 
2928 	if (r == -EADDRINUSE) {
2929 		if (addr >= bo_s && addr <= bo_l)
2930 			return NULL;
2931 
2932 		/* Create one page svm range if 2MB range overlapping */
2933 		start = addr;
2934 		last = addr;
2935 	}
2936 
2937 	prange = svm_range_new(&p->svms, start, last, true);
2938 	if (!prange) {
2939 		pr_debug("Failed to create prange in address [0x%llx]\n", addr);
2940 		return NULL;
2941 	}
2942 	if (kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx)) {
2943 		pr_debug("failed to get gpuid from kgd\n");
2944 		svm_range_free(prange, true);
2945 		return NULL;
2946 	}
2947 
2948 	if (is_heap_stack)
2949 		prange->preferred_loc = KFD_IOCTL_SVM_LOCATION_SYSMEM;
2950 
2951 	svm_range_add_to_svms(prange);
2952 	svm_range_add_notifier_locked(mm, prange);
2953 
2954 	return prange;
2955 }
2956 
2957 /* svm_range_skip_recover - decide if prange can be recovered
2958  * @prange: svm range structure
2959  *
2960  * GPU vm retry fault handle skip recover the range for cases:
2961  * 1. prange is on deferred list to be removed after unmap, it is stale fault,
2962  *    deferred list work will drain the stale fault before free the prange.
2963  * 2. prange is on deferred list to add interval notifier after split, or
2964  * 3. prange is child range, it is split from parent prange, recover later
2965  *    after interval notifier is added.
2966  *
2967  * Return: true to skip recover, false to recover
2968  */
2969 static bool svm_range_skip_recover(struct svm_range *prange)
2970 {
2971 	struct svm_range_list *svms = prange->svms;
2972 
2973 	spin_lock(&svms->deferred_list_lock);
2974 	if (list_empty(&prange->deferred_list) &&
2975 	    list_empty(&prange->child_list)) {
2976 		spin_unlock(&svms->deferred_list_lock);
2977 		return false;
2978 	}
2979 	spin_unlock(&svms->deferred_list_lock);
2980 
2981 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2982 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] unmapped\n",
2983 			 svms, prange, prange->start, prange->last);
2984 		return true;
2985 	}
2986 	if (prange->work_item.op == SVM_OP_ADD_RANGE_AND_MAP ||
2987 	    prange->work_item.op == SVM_OP_ADD_RANGE) {
2988 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] not added yet\n",
2989 			 svms, prange, prange->start, prange->last);
2990 		return true;
2991 	}
2992 	return false;
2993 }
2994 
2995 static void
2996 svm_range_count_fault(struct kfd_node *node, struct kfd_process *p,
2997 		      int32_t gpuidx)
2998 {
2999 	struct kfd_process_device *pdd;
3000 
3001 	/* fault is on different page of same range
3002 	 * or fault is skipped to recover later
3003 	 * or fault is on invalid virtual address
3004 	 */
3005 	if (gpuidx == MAX_GPU_INSTANCE) {
3006 		uint32_t gpuid;
3007 		int r;
3008 
3009 		r = kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx);
3010 		if (r < 0)
3011 			return;
3012 	}
3013 
3014 	/* fault is recovered
3015 	 * or fault cannot recover because GPU no access on the range
3016 	 */
3017 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
3018 	if (pdd)
3019 		WRITE_ONCE(pdd->faults, pdd->faults + 1);
3020 }
3021 
3022 static bool
3023 svm_fault_allowed(struct vm_area_struct *vma, bool write_fault)
3024 {
3025 	unsigned long requested = VM_READ;
3026 
3027 	if (write_fault)
3028 		requested |= VM_WRITE;
3029 
3030 	pr_debug("requested 0x%lx, vma permission flags 0x%lx\n", requested,
3031 		vma->vm_flags);
3032 	return (vma->vm_flags & requested) == requested;
3033 }
3034 
3035 int
3036 svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
3037 			uint32_t vmid, uint32_t node_id,
3038 			uint64_t addr, uint64_t ts, bool write_fault)
3039 {
3040 	unsigned long start, last, size;
3041 	struct mm_struct *mm = NULL;
3042 	struct svm_range_list *svms;
3043 	struct svm_range *prange;
3044 	struct kfd_process *p;
3045 	ktime_t timestamp = ktime_get_boottime();
3046 	struct kfd_node *node;
3047 	int32_t best_loc;
3048 	int32_t gpuid, gpuidx = MAX_GPU_INSTANCE;
3049 	bool write_locked = false;
3050 	struct vm_area_struct *vma;
3051 	bool migration = false;
3052 	int r = 0;
3053 
3054 	if (!KFD_IS_SVM_API_SUPPORTED(adev)) {
3055 		pr_debug("device does not support SVM\n");
3056 		return -EFAULT;
3057 	}
3058 
3059 	p = kfd_lookup_process_by_pasid(pasid, NULL);
3060 	if (!p) {
3061 		pr_debug("kfd process not founded pasid 0x%x\n", pasid);
3062 		return 0;
3063 	}
3064 	svms = &p->svms;
3065 
3066 	pr_debug("restoring svms 0x%p fault address 0x%llx\n", svms, addr);
3067 
3068 	if (atomic_read(&svms->drain_pagefaults)) {
3069 		pr_debug("page fault handling disabled, drop fault 0x%llx\n", addr);
3070 		r = 0;
3071 		goto out;
3072 	}
3073 
3074 	node = kfd_node_by_irq_ids(adev, node_id, vmid);
3075 	if (!node) {
3076 		pr_debug("kfd node does not exist node_id: %d, vmid: %d\n", node_id,
3077 			 vmid);
3078 		r = -EFAULT;
3079 		goto out;
3080 	}
3081 
3082 	if (kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx)) {
3083 		pr_debug("failed to get gpuid/gpuidex for node_id: %d\n", node_id);
3084 		r = -EFAULT;
3085 		goto out;
3086 	}
3087 
3088 	if (!p->xnack_enabled) {
3089 		pr_debug("XNACK not enabled for pasid 0x%x\n", pasid);
3090 		r = -EFAULT;
3091 		goto out;
3092 	}
3093 
3094 	/* p->lead_thread is available as kfd_process_wq_release flush the work
3095 	 * before releasing task ref.
3096 	 */
3097 	mm = get_task_mm(p->lead_thread);
3098 	if (!mm) {
3099 		pr_debug("svms 0x%p failed to get mm\n", svms);
3100 		r = 0;
3101 		goto out;
3102 	}
3103 
3104 	mmap_read_lock(mm);
3105 retry_write_locked:
3106 	mutex_lock(&svms->lock);
3107 
3108 	/* check if this page fault time stamp is before svms->checkpoint_ts */
3109 	if (svms->checkpoint_ts[gpuidx] != 0) {
3110 		if (amdgpu_ih_ts_after_or_equal(ts,  svms->checkpoint_ts[gpuidx])) {
3111 			pr_debug("draining retry fault, drop fault 0x%llx\n", addr);
3112 			if (write_locked)
3113 				mmap_write_downgrade(mm);
3114 			r = -EAGAIN;
3115 			goto out_unlock_svms;
3116 		} else {
3117 			/* ts is after svms->checkpoint_ts now, reset svms->checkpoint_ts
3118 			 * to zero to avoid following ts wrap around give wrong comparing
3119 			 */
3120 			svms->checkpoint_ts[gpuidx] = 0;
3121 		}
3122 	}
3123 
3124 	prange = svm_range_from_addr(svms, addr, NULL);
3125 	if (!prange) {
3126 		pr_debug("failed to find prange svms 0x%p address [0x%llx]\n",
3127 			 svms, addr);
3128 		if (!write_locked) {
3129 			/* Need the write lock to create new range with MMU notifier.
3130 			 * Also flush pending deferred work to make sure the interval
3131 			 * tree is up to date before we add a new range
3132 			 */
3133 			mutex_unlock(&svms->lock);
3134 			mmap_read_unlock(mm);
3135 			mmap_write_lock(mm);
3136 			write_locked = true;
3137 			goto retry_write_locked;
3138 		}
3139 		prange = svm_range_create_unregistered_range(node, p, mm, addr);
3140 		if (!prange) {
3141 			pr_debug("failed to create unregistered range svms 0x%p address [0x%llx]\n",
3142 				 svms, addr);
3143 			mmap_write_downgrade(mm);
3144 			r = -EFAULT;
3145 			goto out_unlock_svms;
3146 		}
3147 	}
3148 	if (write_locked)
3149 		mmap_write_downgrade(mm);
3150 
3151 	mutex_lock(&prange->migrate_mutex);
3152 
3153 	if (svm_range_skip_recover(prange)) {
3154 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
3155 		r = 0;
3156 		goto out_unlock_range;
3157 	}
3158 
3159 	/* skip duplicate vm fault on different pages of same range */
3160 	if (ktime_before(timestamp, ktime_add_ns(prange->validate_timestamp,
3161 				AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING))) {
3162 		pr_debug("svms 0x%p [0x%lx %lx] already restored\n",
3163 			 svms, prange->start, prange->last);
3164 		r = 0;
3165 		goto out_unlock_range;
3166 	}
3167 
3168 	/* __do_munmap removed VMA, return success as we are handling stale
3169 	 * retry fault.
3170 	 */
3171 	vma = vma_lookup(mm, addr << PAGE_SHIFT);
3172 	if (!vma) {
3173 		pr_debug("address 0x%llx VMA is removed\n", addr);
3174 		r = 0;
3175 		goto out_unlock_range;
3176 	}
3177 
3178 	if (!svm_fault_allowed(vma, write_fault)) {
3179 		pr_debug("fault addr 0x%llx no %s permission\n", addr,
3180 			write_fault ? "write" : "read");
3181 		r = -EPERM;
3182 		goto out_unlock_range;
3183 	}
3184 
3185 	best_loc = svm_range_best_restore_location(prange, node, &gpuidx);
3186 	if (best_loc == -1) {
3187 		pr_debug("svms %p failed get best restore loc [0x%lx 0x%lx]\n",
3188 			 svms, prange->start, prange->last);
3189 		r = -EACCES;
3190 		goto out_unlock_range;
3191 	}
3192 
3193 	pr_debug("svms %p [0x%lx 0x%lx] best restore 0x%x, actual loc 0x%x\n",
3194 		 svms, prange->start, prange->last, best_loc,
3195 		 prange->actual_loc);
3196 
3197 	kfd_smi_event_page_fault_start(node, p->lead_thread->pid, addr,
3198 				       write_fault, timestamp);
3199 
3200 	/* Align migration range start and size to granularity size */
3201 	size = 1UL << prange->granularity;
3202 	start = max_t(unsigned long, ALIGN_DOWN(addr, size), prange->start);
3203 	last = min_t(unsigned long, ALIGN(addr + 1, size) - 1, prange->last);
3204 	if (prange->actual_loc != 0 || best_loc != 0) {
3205 		if (best_loc) {
3206 			r = svm_migrate_to_vram(prange, best_loc, start, last,
3207 					mm, KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU);
3208 			if (r) {
3209 				pr_debug("svm_migrate_to_vram failed (%d) at %llx, falling back to system memory\n",
3210 					 r, addr);
3211 				/* Fallback to system memory if migration to
3212 				 * VRAM failed
3213 				 */
3214 				if (prange->actual_loc && prange->actual_loc != best_loc)
3215 					r = svm_migrate_vram_to_ram(prange, mm, start, last,
3216 						KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU, NULL);
3217 				else
3218 					r = 0;
3219 			}
3220 		} else {
3221 			r = svm_migrate_vram_to_ram(prange, mm, start, last,
3222 					KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU, NULL);
3223 		}
3224 		if (r) {
3225 			pr_debug("failed %d to migrate svms %p [0x%lx 0x%lx]\n",
3226 				 r, svms, start, last);
3227 			goto out_migrate_fail;
3228 		} else {
3229 			migration = true;
3230 		}
3231 	}
3232 
3233 	r = svm_range_validate_and_map(mm, start, last, prange, gpuidx, false,
3234 				       false, false);
3235 	if (r)
3236 		pr_debug("failed %d to map svms 0x%p [0x%lx 0x%lx] to gpus\n",
3237 			 r, svms, start, last);
3238 
3239 out_migrate_fail:
3240 	kfd_smi_event_page_fault_end(node, p->lead_thread->pid, addr,
3241 				     migration);
3242 
3243 out_unlock_range:
3244 	mutex_unlock(&prange->migrate_mutex);
3245 out_unlock_svms:
3246 	mutex_unlock(&svms->lock);
3247 	mmap_read_unlock(mm);
3248 
3249 	if (r != -EAGAIN)
3250 		svm_range_count_fault(node, p, gpuidx);
3251 
3252 	mmput(mm);
3253 out:
3254 	kfd_unref_process(p);
3255 
3256 	if (r == -EAGAIN) {
3257 		pr_debug("recover vm fault later\n");
3258 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
3259 		r = 0;
3260 	}
3261 	return r;
3262 }
3263 
3264 int
3265 svm_range_switch_xnack_reserve_mem(struct kfd_process *p, bool xnack_enabled)
3266 {
3267 	struct svm_range *prange, *pchild;
3268 	uint64_t reserved_size = 0;
3269 	uint64_t size;
3270 	int r = 0;
3271 
3272 	pr_debug("switching xnack from %d to %d\n", p->xnack_enabled, xnack_enabled);
3273 
3274 	mutex_lock(&p->svms.lock);
3275 
3276 	list_for_each_entry(prange, &p->svms.list, list) {
3277 		svm_range_lock(prange);
3278 		list_for_each_entry(pchild, &prange->child_list, child_list) {
3279 			size = (pchild->last - pchild->start + 1) << PAGE_SHIFT;
3280 			if (xnack_enabled) {
3281 				amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3282 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3283 			} else {
3284 				r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3285 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3286 				if (r)
3287 					goto out_unlock;
3288 				reserved_size += size;
3289 			}
3290 		}
3291 
3292 		size = (prange->last - prange->start + 1) << PAGE_SHIFT;
3293 		if (xnack_enabled) {
3294 			amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3295 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3296 		} else {
3297 			r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3298 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3299 			if (r)
3300 				goto out_unlock;
3301 			reserved_size += size;
3302 		}
3303 out_unlock:
3304 		svm_range_unlock(prange);
3305 		if (r)
3306 			break;
3307 	}
3308 
3309 	if (r)
3310 		amdgpu_amdkfd_unreserve_mem_limit(NULL, reserved_size,
3311 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3312 	else
3313 		/* Change xnack mode must be inside svms lock, to avoid race with
3314 		 * svm_range_deferred_list_work unreserve memory in parallel.
3315 		 */
3316 		p->xnack_enabled = xnack_enabled;
3317 
3318 	mutex_unlock(&p->svms.lock);
3319 	return r;
3320 }
3321 
3322 void svm_range_list_fini(struct kfd_process *p)
3323 {
3324 	struct svm_range *prange;
3325 	struct svm_range *next;
3326 
3327 	pr_debug("process pid %d svms 0x%p\n", p->lead_thread->pid,
3328 		 &p->svms);
3329 
3330 	cancel_delayed_work_sync(&p->svms.restore_work);
3331 
3332 	/* Ensure list work is finished before process is destroyed */
3333 	flush_work(&p->svms.deferred_list_work);
3334 
3335 	/*
3336 	 * Ensure no retry fault comes in afterwards, as page fault handler will
3337 	 * not find kfd process and take mm lock to recover fault.
3338 	 * stop kfd page fault handing, then wait pending page faults got drained
3339 	 */
3340 	atomic_set(&p->svms.drain_pagefaults, 1);
3341 	svm_range_drain_retry_fault(&p->svms);
3342 
3343 	list_for_each_entry_safe(prange, next, &p->svms.list, list) {
3344 		svm_range_unlink(prange);
3345 		svm_range_remove_notifier(prange);
3346 		svm_range_free(prange, true);
3347 	}
3348 
3349 	mutex_destroy(&p->svms.lock);
3350 
3351 	pr_debug("process pid %d svms 0x%p done\n",
3352 		p->lead_thread->pid, &p->svms);
3353 }
3354 
3355 int svm_range_list_init(struct kfd_process *p)
3356 {
3357 	struct svm_range_list *svms = &p->svms;
3358 	int i;
3359 
3360 	svms->objects = RB_ROOT_CACHED;
3361 	mutex_init(&svms->lock);
3362 	INIT_LIST_HEAD(&svms->list);
3363 	atomic_set(&svms->evicted_ranges, 0);
3364 	atomic_set(&svms->drain_pagefaults, 0);
3365 	INIT_DELAYED_WORK(&svms->restore_work, svm_range_restore_work);
3366 	INIT_WORK(&svms->deferred_list_work, svm_range_deferred_list_work);
3367 	INIT_LIST_HEAD(&svms->deferred_range_list);
3368 	INIT_LIST_HEAD(&svms->criu_svm_metadata_list);
3369 	spin_lock_init(&svms->deferred_list_lock);
3370 
3371 	for (i = 0; i < p->n_pdds; i++)
3372 		if (KFD_IS_SVM_API_SUPPORTED(p->pdds[i]->dev->adev))
3373 			bitmap_set(svms->bitmap_supported, i, 1);
3374 
3375 	 /* Value of default granularity cannot exceed 0x1B, the
3376 	  * number of pages supported by a 4-level paging table
3377 	  */
3378 	svms->default_granularity = min_t(u8, amdgpu_svm_default_granularity, 0x1B);
3379 	pr_debug("Default SVM Granularity to use: %d\n", svms->default_granularity);
3380 
3381 	return 0;
3382 }
3383 
3384 /**
3385  * svm_range_check_vm - check if virtual address range mapped already
3386  * @p: current kfd_process
3387  * @start: range start address, in pages
3388  * @last: range last address, in pages
3389  * @bo_s: mapping start address in pages if address range already mapped
3390  * @bo_l: mapping last address in pages if address range already mapped
3391  *
3392  * The purpose is to avoid virtual address ranges already allocated by
3393  * kfd_ioctl_alloc_memory_of_gpu ioctl.
3394  * It looks for each pdd in the kfd_process.
3395  *
3396  * Context: Process context
3397  *
3398  * Return 0 - OK, if the range is not mapped.
3399  * Otherwise error code:
3400  * -EADDRINUSE - if address is mapped already by kfd_ioctl_alloc_memory_of_gpu
3401  * -ERESTARTSYS - A wait for the buffer to become unreserved was interrupted by
3402  * a signal. Release all buffer reservations and return to user-space.
3403  */
3404 static int
3405 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
3406 		   uint64_t *bo_s, uint64_t *bo_l)
3407 {
3408 	struct amdgpu_bo_va_mapping *mapping;
3409 	struct interval_tree_node *node;
3410 	uint32_t i;
3411 	int r;
3412 
3413 	for (i = 0; i < p->n_pdds; i++) {
3414 		struct amdgpu_vm *vm;
3415 
3416 		if (!p->pdds[i]->drm_priv)
3417 			continue;
3418 
3419 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
3420 		r = amdgpu_bo_reserve(vm->root.bo, false);
3421 		if (r)
3422 			return r;
3423 
3424 		node = interval_tree_iter_first(&vm->va, start, last);
3425 		if (node) {
3426 			pr_debug("range [0x%llx 0x%llx] already TTM mapped\n",
3427 				 start, last);
3428 			mapping = container_of((struct rb_node *)node,
3429 					       struct amdgpu_bo_va_mapping, rb);
3430 			if (bo_s && bo_l) {
3431 				*bo_s = mapping->start;
3432 				*bo_l = mapping->last;
3433 			}
3434 			amdgpu_bo_unreserve(vm->root.bo);
3435 			return -EADDRINUSE;
3436 		}
3437 		amdgpu_bo_unreserve(vm->root.bo);
3438 	}
3439 
3440 	return 0;
3441 }
3442 
3443 /**
3444  * svm_range_is_valid - check if virtual address range is valid
3445  * @p: current kfd_process
3446  * @start: range start address, in pages
3447  * @size: range size, in pages
3448  *
3449  * Valid virtual address range means it belongs to one or more VMAs
3450  *
3451  * Context: Process context
3452  *
3453  * Return:
3454  *  0 - OK, otherwise error code
3455  */
3456 static int
3457 svm_range_is_valid(struct kfd_process *p, uint64_t start, uint64_t size)
3458 {
3459 	const unsigned long device_vma = VM_IO | VM_PFNMAP | VM_MIXEDMAP;
3460 	struct vm_area_struct *vma;
3461 	unsigned long end;
3462 	unsigned long start_unchg = start;
3463 
3464 	start <<= PAGE_SHIFT;
3465 	end = start + (size << PAGE_SHIFT);
3466 	do {
3467 		vma = vma_lookup(p->mm, start);
3468 		if (!vma || (vma->vm_flags & device_vma))
3469 			return -EFAULT;
3470 		start = min(end, vma->vm_end);
3471 	} while (start < end);
3472 
3473 	return svm_range_check_vm(p, start_unchg, (end - 1) >> PAGE_SHIFT, NULL,
3474 				  NULL);
3475 }
3476 
3477 /**
3478  * svm_range_best_prefetch_location - decide the best prefetch location
3479  * @prange: svm range structure
3480  *
3481  * For xnack off:
3482  * If range map to single GPU, the best prefetch location is prefetch_loc, which
3483  * can be CPU or GPU.
3484  *
3485  * If range is ACCESS or ACCESS_IN_PLACE by mGPUs, only if mGPU connection on
3486  * XGMI same hive, the best prefetch location is prefetch_loc GPU, othervise
3487  * the best prefetch location is always CPU, because GPU can not have coherent
3488  * mapping VRAM of other GPUs even with large-BAR PCIe connection.
3489  *
3490  * For xnack on:
3491  * If range is not ACCESS_IN_PLACE by mGPUs, the best prefetch location is
3492  * prefetch_loc, other GPU access will generate vm fault and trigger migration.
3493  *
3494  * If range is ACCESS_IN_PLACE by mGPUs, only if mGPU connection on XGMI same
3495  * hive, the best prefetch location is prefetch_loc GPU, otherwise the best
3496  * prefetch location is always CPU.
3497  *
3498  * Context: Process context
3499  *
3500  * Return:
3501  * 0 for CPU or GPU id
3502  */
3503 static uint32_t
3504 svm_range_best_prefetch_location(struct svm_range *prange)
3505 {
3506 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
3507 	uint32_t best_loc = prange->prefetch_loc;
3508 	struct kfd_process_device *pdd;
3509 	struct kfd_node *bo_node;
3510 	struct kfd_process *p;
3511 	uint32_t gpuidx;
3512 
3513 	p = container_of(prange->svms, struct kfd_process, svms);
3514 
3515 	if (!best_loc || best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED)
3516 		goto out;
3517 
3518 	bo_node = svm_range_get_node_by_id(prange, best_loc);
3519 	if (!bo_node) {
3520 		WARN_ONCE(1, "failed to get valid kfd node at id%x\n", best_loc);
3521 		best_loc = 0;
3522 		goto out;
3523 	}
3524 
3525 	if (bo_node->adev->apu_prefer_gtt) {
3526 		best_loc = 0;
3527 		goto out;
3528 	}
3529 
3530 	if (p->xnack_enabled)
3531 		bitmap_copy(bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
3532 	else
3533 		bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
3534 			  MAX_GPU_INSTANCE);
3535 
3536 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
3537 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
3538 		if (!pdd) {
3539 			pr_debug("failed to get device by idx 0x%x\n", gpuidx);
3540 			continue;
3541 		}
3542 
3543 		if (pdd->dev->adev == bo_node->adev)
3544 			continue;
3545 
3546 		if (!svm_nodes_in_same_hive(pdd->dev, bo_node)) {
3547 			best_loc = 0;
3548 			break;
3549 		}
3550 	}
3551 
3552 out:
3553 	pr_debug("xnack %d svms 0x%p [0x%lx 0x%lx] best loc 0x%x\n",
3554 		 p->xnack_enabled, &p->svms, prange->start, prange->last,
3555 		 best_loc);
3556 
3557 	return best_loc;
3558 }
3559 
3560 /* svm_range_trigger_migration - start page migration if prefetch loc changed
3561  * @mm: current process mm_struct
3562  * @prange: svm range structure
3563  * @migrated: output, true if migration is triggered
3564  *
3565  * If range perfetch_loc is GPU, actual loc is cpu 0, then migrate the range
3566  * from ram to vram.
3567  * If range prefetch_loc is cpu 0, actual loc is GPU, then migrate the range
3568  * from vram to ram.
3569  *
3570  * If GPU vm fault retry is not enabled, migration interact with MMU notifier
3571  * and restore work:
3572  * 1. migrate_vma_setup invalidate pages, MMU notifier callback svm_range_evict
3573  *    stops all queues, schedule restore work
3574  * 2. svm_range_restore_work wait for migration is done by
3575  *    a. svm_range_validate_vram takes prange->migrate_mutex
3576  *    b. svm_range_validate_ram HMM get pages wait for CPU fault handle returns
3577  * 3. restore work update mappings of GPU, resume all queues.
3578  *
3579  * Context: Process context
3580  *
3581  * Return:
3582  * 0 - OK, otherwise - error code of migration
3583  */
3584 static int
3585 svm_range_trigger_migration(struct mm_struct *mm, struct svm_range *prange,
3586 			    bool *migrated)
3587 {
3588 	uint32_t best_loc;
3589 	int r = 0;
3590 
3591 	*migrated = false;
3592 	best_loc = svm_range_best_prefetch_location(prange);
3593 
3594 	/* when best_loc is a gpu node and same as prange->actual_loc
3595 	 * we still need do migration as prange->actual_loc !=0 does
3596 	 * not mean all pages in prange are vram. hmm migrate will pick
3597 	 * up right pages during migration.
3598 	 */
3599 	if ((best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED) ||
3600 	    (best_loc == 0 && prange->actual_loc == 0))
3601 		return 0;
3602 
3603 	if (!best_loc) {
3604 		r = svm_migrate_vram_to_ram(prange, mm, prange->start, prange->last,
3605 					KFD_MIGRATE_TRIGGER_PREFETCH, NULL);
3606 		*migrated = !r;
3607 		return r;
3608 	}
3609 
3610 	r = svm_migrate_to_vram(prange, best_loc, prange->start, prange->last,
3611 				mm, KFD_MIGRATE_TRIGGER_PREFETCH);
3612 	*migrated = !r;
3613 
3614 	return 0;
3615 }
3616 
3617 int svm_range_schedule_evict_svm_bo(struct amdgpu_amdkfd_fence *fence)
3618 {
3619 	/* Dereferencing fence->svm_bo is safe here because the fence hasn't
3620 	 * signaled yet and we're under the protection of the fence->lock.
3621 	 * After the fence is signaled in svm_range_bo_release, we cannot get
3622 	 * here any more.
3623 	 *
3624 	 * Reference is dropped in svm_range_evict_svm_bo_worker.
3625 	 */
3626 	if (svm_bo_ref_unless_zero(fence->svm_bo)) {
3627 		WRITE_ONCE(fence->svm_bo->evicting, 1);
3628 		schedule_work(&fence->svm_bo->eviction_work);
3629 	}
3630 
3631 	return 0;
3632 }
3633 
3634 static void svm_range_evict_svm_bo_worker(struct work_struct *work)
3635 {
3636 	struct svm_range_bo *svm_bo;
3637 	struct mm_struct *mm;
3638 	int r = 0;
3639 
3640 	svm_bo = container_of(work, struct svm_range_bo, eviction_work);
3641 
3642 	if (mmget_not_zero(svm_bo->eviction_fence->mm)) {
3643 		mm = svm_bo->eviction_fence->mm;
3644 	} else {
3645 		svm_range_bo_unref(svm_bo);
3646 		return;
3647 	}
3648 
3649 	mmap_read_lock(mm);
3650 	spin_lock(&svm_bo->list_lock);
3651 	while (!list_empty(&svm_bo->range_list) && !r) {
3652 		struct svm_range *prange =
3653 				list_first_entry(&svm_bo->range_list,
3654 						struct svm_range, svm_bo_list);
3655 		int retries = 3;
3656 
3657 		list_del_init(&prange->svm_bo_list);
3658 		spin_unlock(&svm_bo->list_lock);
3659 
3660 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
3661 			 prange->start, prange->last);
3662 
3663 		mutex_lock(&prange->migrate_mutex);
3664 		do {
3665 			/* migrate all vram pages in this prange to sys ram
3666 			 * after that prange->actual_loc should be zero
3667 			 */
3668 			r = svm_migrate_vram_to_ram(prange, mm,
3669 					prange->start, prange->last,
3670 					KFD_MIGRATE_TRIGGER_TTM_EVICTION, NULL);
3671 		} while (!r && prange->actual_loc && --retries);
3672 
3673 		if (!r && prange->actual_loc)
3674 			pr_info_once("Migration failed during eviction");
3675 
3676 		if (!prange->actual_loc) {
3677 			mutex_lock(&prange->lock);
3678 			prange->svm_bo = NULL;
3679 			mutex_unlock(&prange->lock);
3680 		}
3681 		mutex_unlock(&prange->migrate_mutex);
3682 
3683 		spin_lock(&svm_bo->list_lock);
3684 	}
3685 	spin_unlock(&svm_bo->list_lock);
3686 	mmap_read_unlock(mm);
3687 	mmput(mm);
3688 
3689 	dma_fence_signal(&svm_bo->eviction_fence->base);
3690 
3691 	/* This is the last reference to svm_bo, after svm_range_vram_node_free
3692 	 * has been called in svm_migrate_vram_to_ram
3693 	 */
3694 	WARN_ONCE(!r && kref_read(&svm_bo->kref) != 1, "This was not the last reference\n");
3695 	svm_range_bo_unref(svm_bo);
3696 }
3697 
3698 static int
3699 svm_range_set_attr(struct kfd_process *p, struct mm_struct *mm,
3700 		   uint64_t start, uint64_t size, uint32_t nattr,
3701 		   struct kfd_ioctl_svm_attribute *attrs)
3702 {
3703 	struct amdkfd_process_info *process_info = p->kgd_process_info;
3704 	struct list_head update_list;
3705 	struct list_head insert_list;
3706 	struct list_head remove_list;
3707 	struct list_head remap_list;
3708 	struct svm_range_list *svms;
3709 	struct svm_range *prange;
3710 	struct svm_range *next;
3711 	bool update_mapping = false;
3712 	bool flush_tlb;
3713 	int r, ret = 0;
3714 
3715 	pr_debug("process pid %d svms 0x%p [0x%llx 0x%llx] pages 0x%llx\n",
3716 		 p->lead_thread->pid, &p->svms, start, start + size - 1, size);
3717 
3718 	r = svm_range_check_attr(p, nattr, attrs);
3719 	if (r)
3720 		return r;
3721 
3722 	svms = &p->svms;
3723 
3724 	mutex_lock(&process_info->lock);
3725 
3726 	svm_range_list_lock_and_flush_work(svms, mm);
3727 
3728 	r = svm_range_is_valid(p, start, size);
3729 	if (r) {
3730 		pr_debug("invalid range r=%d\n", r);
3731 		mmap_write_unlock(mm);
3732 		goto out;
3733 	}
3734 
3735 	mutex_lock(&svms->lock);
3736 
3737 	/* Add new range and split existing ranges as needed */
3738 	r = svm_range_add(p, start, size, nattr, attrs, &update_list,
3739 			  &insert_list, &remove_list, &remap_list);
3740 	if (r) {
3741 		mutex_unlock(&svms->lock);
3742 		mmap_write_unlock(mm);
3743 		goto out;
3744 	}
3745 	/* Apply changes as a transaction */
3746 	list_for_each_entry_safe(prange, next, &insert_list, list) {
3747 		svm_range_add_to_svms(prange);
3748 		svm_range_add_notifier_locked(mm, prange);
3749 	}
3750 	list_for_each_entry(prange, &update_list, update_list) {
3751 		svm_range_apply_attrs(p, prange, nattr, attrs, &update_mapping);
3752 		/* TODO: unmap ranges from GPU that lost access */
3753 	}
3754 	update_mapping |= !p->xnack_enabled && !list_empty(&remap_list);
3755 
3756 	list_for_each_entry_safe(prange, next, &remove_list, update_list) {
3757 		pr_debug("unlink old 0x%p prange 0x%p [0x%lx 0x%lx]\n",
3758 			 prange->svms, prange, prange->start,
3759 			 prange->last);
3760 		svm_range_unlink(prange);
3761 		svm_range_remove_notifier(prange);
3762 		svm_range_free(prange, false);
3763 	}
3764 
3765 	mmap_write_downgrade(mm);
3766 	/* Trigger migrations and revalidate and map to GPUs as needed. If
3767 	 * this fails we may be left with partially completed actions. There
3768 	 * is no clean way of rolling back to the previous state in such a
3769 	 * case because the rollback wouldn't be guaranteed to work either.
3770 	 */
3771 	list_for_each_entry(prange, &update_list, update_list) {
3772 		bool migrated;
3773 
3774 		mutex_lock(&prange->migrate_mutex);
3775 
3776 		r = svm_range_trigger_migration(mm, prange, &migrated);
3777 		if (r)
3778 			goto out_unlock_range;
3779 
3780 		if (migrated && (!p->xnack_enabled ||
3781 		    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) &&
3782 		    prange->mapped_to_gpu) {
3783 			pr_debug("restore_work will update mappings of GPUs\n");
3784 			mutex_unlock(&prange->migrate_mutex);
3785 			continue;
3786 		}
3787 
3788 		if (!migrated && !update_mapping) {
3789 			mutex_unlock(&prange->migrate_mutex);
3790 			continue;
3791 		}
3792 
3793 		flush_tlb = !migrated && update_mapping && prange->mapped_to_gpu;
3794 
3795 		r = svm_range_validate_and_map(mm, prange->start, prange->last, prange,
3796 					       MAX_GPU_INSTANCE, true, true, flush_tlb);
3797 		if (r)
3798 			pr_debug("failed %d to map svm range\n", r);
3799 
3800 out_unlock_range:
3801 		mutex_unlock(&prange->migrate_mutex);
3802 		if (r)
3803 			ret = r;
3804 	}
3805 
3806 	list_for_each_entry(prange, &remap_list, update_list) {
3807 		pr_debug("Remapping prange 0x%p [0x%lx 0x%lx]\n",
3808 			 prange, prange->start, prange->last);
3809 		mutex_lock(&prange->migrate_mutex);
3810 		r = svm_range_validate_and_map(mm,  prange->start, prange->last, prange,
3811 					       MAX_GPU_INSTANCE, true, true, prange->mapped_to_gpu);
3812 		if (r)
3813 			pr_debug("failed %d on remap svm range\n", r);
3814 		mutex_unlock(&prange->migrate_mutex);
3815 		if (r)
3816 			ret = r;
3817 	}
3818 
3819 	dynamic_svm_range_dump(svms);
3820 
3821 	mutex_unlock(&svms->lock);
3822 	mmap_read_unlock(mm);
3823 out:
3824 	mutex_unlock(&process_info->lock);
3825 
3826 	pr_debug("process pid %d svms 0x%p [0x%llx 0x%llx] done, r=%d\n",
3827 		 p->lead_thread->pid, &p->svms, start, start + size - 1, r);
3828 
3829 	return ret ? ret : r;
3830 }
3831 
3832 static int
3833 svm_range_get_attr(struct kfd_process *p, struct mm_struct *mm,
3834 		   uint64_t start, uint64_t size, uint32_t nattr,
3835 		   struct kfd_ioctl_svm_attribute *attrs)
3836 {
3837 	DECLARE_BITMAP(bitmap_access, MAX_GPU_INSTANCE);
3838 	DECLARE_BITMAP(bitmap_aip, MAX_GPU_INSTANCE);
3839 	bool get_preferred_loc = false;
3840 	bool get_prefetch_loc = false;
3841 	bool get_granularity = false;
3842 	bool get_accessible = false;
3843 	bool get_flags = false;
3844 	uint64_t last = start + size - 1UL;
3845 	uint8_t granularity = 0xff;
3846 	struct interval_tree_node *node;
3847 	struct svm_range_list *svms;
3848 	struct svm_range *prange;
3849 	uint32_t prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3850 	uint32_t location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3851 	uint32_t flags_and = 0xffffffff;
3852 	uint32_t flags_or = 0;
3853 	int gpuidx;
3854 	uint32_t i;
3855 	int r = 0;
3856 
3857 	pr_debug("svms 0x%p [0x%llx 0x%llx] nattr 0x%x\n", &p->svms, start,
3858 		 start + size - 1, nattr);
3859 
3860 	/* Flush pending deferred work to avoid racing with deferred actions from
3861 	 * previous memory map changes (e.g. munmap). Concurrent memory map changes
3862 	 * can still race with get_attr because we don't hold the mmap lock. But that
3863 	 * would be a race condition in the application anyway, and undefined
3864 	 * behaviour is acceptable in that case.
3865 	 */
3866 	flush_work(&p->svms.deferred_list_work);
3867 
3868 	mmap_read_lock(mm);
3869 	r = svm_range_is_valid(p, start, size);
3870 	mmap_read_unlock(mm);
3871 	if (r) {
3872 		pr_debug("invalid range r=%d\n", r);
3873 		return r;
3874 	}
3875 
3876 	for (i = 0; i < nattr; i++) {
3877 		switch (attrs[i].type) {
3878 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3879 			get_preferred_loc = true;
3880 			break;
3881 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3882 			get_prefetch_loc = true;
3883 			break;
3884 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3885 			get_accessible = true;
3886 			break;
3887 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3888 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3889 			get_flags = true;
3890 			break;
3891 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3892 			get_granularity = true;
3893 			break;
3894 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
3895 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
3896 			fallthrough;
3897 		default:
3898 			pr_debug("get invalid attr type 0x%x\n", attrs[i].type);
3899 			return -EINVAL;
3900 		}
3901 	}
3902 
3903 	svms = &p->svms;
3904 
3905 	mutex_lock(&svms->lock);
3906 
3907 	node = interval_tree_iter_first(&svms->objects, start, last);
3908 	if (!node) {
3909 		pr_debug("range attrs not found return default values\n");
3910 		svm_range_set_default_attributes(svms, &location, &prefetch_loc,
3911 						 &granularity, &flags_and);
3912 		flags_or = flags_and;
3913 		if (p->xnack_enabled)
3914 			bitmap_copy(bitmap_access, svms->bitmap_supported,
3915 				    MAX_GPU_INSTANCE);
3916 		else
3917 			bitmap_zero(bitmap_access, MAX_GPU_INSTANCE);
3918 		bitmap_zero(bitmap_aip, MAX_GPU_INSTANCE);
3919 		goto fill_values;
3920 	}
3921 	bitmap_copy(bitmap_access, svms->bitmap_supported, MAX_GPU_INSTANCE);
3922 	bitmap_copy(bitmap_aip, svms->bitmap_supported, MAX_GPU_INSTANCE);
3923 
3924 	while (node) {
3925 		struct interval_tree_node *next;
3926 
3927 		prange = container_of(node, struct svm_range, it_node);
3928 		next = interval_tree_iter_next(node, start, last);
3929 
3930 		if (get_preferred_loc) {
3931 			if (prange->preferred_loc ==
3932 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3933 			    (location != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3934 			     location != prange->preferred_loc)) {
3935 				location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3936 				get_preferred_loc = false;
3937 			} else {
3938 				location = prange->preferred_loc;
3939 			}
3940 		}
3941 		if (get_prefetch_loc) {
3942 			if (prange->prefetch_loc ==
3943 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3944 			    (prefetch_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3945 			     prefetch_loc != prange->prefetch_loc)) {
3946 				prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3947 				get_prefetch_loc = false;
3948 			} else {
3949 				prefetch_loc = prange->prefetch_loc;
3950 			}
3951 		}
3952 		if (get_accessible) {
3953 			bitmap_and(bitmap_access, bitmap_access,
3954 				   prange->bitmap_access, MAX_GPU_INSTANCE);
3955 			bitmap_and(bitmap_aip, bitmap_aip,
3956 				   prange->bitmap_aip, MAX_GPU_INSTANCE);
3957 		}
3958 		if (get_flags) {
3959 			flags_and &= prange->flags;
3960 			flags_or |= prange->flags;
3961 		}
3962 
3963 		if (get_granularity && prange->granularity < granularity)
3964 			granularity = prange->granularity;
3965 
3966 		node = next;
3967 	}
3968 fill_values:
3969 	mutex_unlock(&svms->lock);
3970 
3971 	for (i = 0; i < nattr; i++) {
3972 		switch (attrs[i].type) {
3973 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3974 			attrs[i].value = location;
3975 			break;
3976 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3977 			attrs[i].value = prefetch_loc;
3978 			break;
3979 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3980 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
3981 							       attrs[i].value);
3982 			if (gpuidx < 0) {
3983 				pr_debug("invalid gpuid %x\n", attrs[i].value);
3984 				return -EINVAL;
3985 			}
3986 			if (test_bit(gpuidx, bitmap_access))
3987 				attrs[i].type = KFD_IOCTL_SVM_ATTR_ACCESS;
3988 			else if (test_bit(gpuidx, bitmap_aip))
3989 				attrs[i].type =
3990 					KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE;
3991 			else
3992 				attrs[i].type = KFD_IOCTL_SVM_ATTR_NO_ACCESS;
3993 			break;
3994 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3995 			attrs[i].value = flags_and;
3996 			break;
3997 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3998 			attrs[i].value = ~flags_or;
3999 			break;
4000 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
4001 			attrs[i].value = (uint32_t)granularity;
4002 			break;
4003 		}
4004 	}
4005 
4006 	return 0;
4007 }
4008 
4009 int kfd_criu_resume_svm(struct kfd_process *p)
4010 {
4011 	struct kfd_ioctl_svm_attribute *set_attr_new, *set_attr = NULL;
4012 	int nattr_common = 4, nattr_accessibility = 1;
4013 	struct criu_svm_metadata *criu_svm_md = NULL;
4014 	struct svm_range_list *svms = &p->svms;
4015 	struct criu_svm_metadata *next = NULL;
4016 	uint32_t set_flags = 0xffffffff;
4017 	int i, j, num_attrs, ret = 0;
4018 	uint64_t set_attr_size;
4019 	struct mm_struct *mm;
4020 
4021 	if (list_empty(&svms->criu_svm_metadata_list)) {
4022 		pr_debug("No SVM data from CRIU restore stage 2\n");
4023 		return ret;
4024 	}
4025 
4026 	mm = get_task_mm(p->lead_thread);
4027 	if (!mm) {
4028 		pr_err("failed to get mm for the target process\n");
4029 		return -ESRCH;
4030 	}
4031 
4032 	num_attrs = nattr_common + (nattr_accessibility * p->n_pdds);
4033 
4034 	i = j = 0;
4035 	list_for_each_entry(criu_svm_md, &svms->criu_svm_metadata_list, list) {
4036 		pr_debug("criu_svm_md[%d]\n\tstart: 0x%llx size: 0x%llx (npages)\n",
4037 			 i, criu_svm_md->data.start_addr, criu_svm_md->data.size);
4038 
4039 		for (j = 0; j < num_attrs; j++) {
4040 			pr_debug("\ncriu_svm_md[%d]->attrs[%d].type : 0x%x\ncriu_svm_md[%d]->attrs[%d].value : 0x%x\n",
4041 				 i, j, criu_svm_md->data.attrs[j].type,
4042 				 i, j, criu_svm_md->data.attrs[j].value);
4043 			switch (criu_svm_md->data.attrs[j].type) {
4044 			/* During Checkpoint operation, the query for
4045 			 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC attribute might
4046 			 * return KFD_IOCTL_SVM_LOCATION_UNDEFINED if they were
4047 			 * not used by the range which was checkpointed. Care
4048 			 * must be taken to not restore with an invalid value
4049 			 * otherwise the gpuidx value will be invalid and
4050 			 * set_attr would eventually fail so just replace those
4051 			 * with another dummy attribute such as
4052 			 * KFD_IOCTL_SVM_ATTR_SET_FLAGS.
4053 			 */
4054 			case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
4055 				if (criu_svm_md->data.attrs[j].value ==
4056 				    KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
4057 					criu_svm_md->data.attrs[j].type =
4058 						KFD_IOCTL_SVM_ATTR_SET_FLAGS;
4059 					criu_svm_md->data.attrs[j].value = 0;
4060 				}
4061 				break;
4062 			case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
4063 				set_flags = criu_svm_md->data.attrs[j].value;
4064 				break;
4065 			default:
4066 				break;
4067 			}
4068 		}
4069 
4070 		/* CLR_FLAGS is not available via get_attr during checkpoint but
4071 		 * it needs to be inserted before restoring the ranges so
4072 		 * allocate extra space for it before calling set_attr
4073 		 */
4074 		set_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4075 						(num_attrs + 1);
4076 		set_attr_new = krealloc(set_attr, set_attr_size,
4077 					    GFP_KERNEL);
4078 		if (!set_attr_new) {
4079 			ret = -ENOMEM;
4080 			goto exit;
4081 		}
4082 		set_attr = set_attr_new;
4083 
4084 		memcpy(set_attr, criu_svm_md->data.attrs, num_attrs *
4085 					sizeof(struct kfd_ioctl_svm_attribute));
4086 		set_attr[num_attrs].type = KFD_IOCTL_SVM_ATTR_CLR_FLAGS;
4087 		set_attr[num_attrs].value = ~set_flags;
4088 
4089 		ret = svm_range_set_attr(p, mm, criu_svm_md->data.start_addr,
4090 					 criu_svm_md->data.size, num_attrs + 1,
4091 					 set_attr);
4092 		if (ret) {
4093 			pr_err("CRIU: failed to set range attributes\n");
4094 			goto exit;
4095 		}
4096 
4097 		i++;
4098 	}
4099 exit:
4100 	kfree(set_attr);
4101 	list_for_each_entry_safe(criu_svm_md, next, &svms->criu_svm_metadata_list, list) {
4102 		pr_debug("freeing criu_svm_md[]\n\tstart: 0x%llx\n",
4103 						criu_svm_md->data.start_addr);
4104 		kfree(criu_svm_md);
4105 	}
4106 
4107 	mmput(mm);
4108 	return ret;
4109 
4110 }
4111 
4112 int kfd_criu_restore_svm(struct kfd_process *p,
4113 			 uint8_t __user *user_priv_ptr,
4114 			 uint64_t *priv_data_offset,
4115 			 uint64_t max_priv_data_size)
4116 {
4117 	uint64_t svm_priv_data_size, svm_object_md_size, svm_attrs_size;
4118 	int nattr_common = 4, nattr_accessibility = 1;
4119 	struct criu_svm_metadata *criu_svm_md = NULL;
4120 	struct svm_range_list *svms = &p->svms;
4121 	uint32_t num_devices;
4122 	int ret = 0;
4123 
4124 	num_devices = p->n_pdds;
4125 	/* Handle one SVM range object at a time, also the number of gpus are
4126 	 * assumed to be same on the restore node, checking must be done while
4127 	 * evaluating the topology earlier
4128 	 */
4129 
4130 	svm_attrs_size = sizeof(struct kfd_ioctl_svm_attribute) *
4131 		(nattr_common + nattr_accessibility * num_devices);
4132 	svm_object_md_size = sizeof(struct criu_svm_metadata) + svm_attrs_size;
4133 
4134 	svm_priv_data_size = sizeof(struct kfd_criu_svm_range_priv_data) +
4135 								svm_attrs_size;
4136 
4137 	criu_svm_md = kzalloc(svm_object_md_size, GFP_KERNEL);
4138 	if (!criu_svm_md) {
4139 		pr_err("failed to allocate memory to store svm metadata\n");
4140 		return -ENOMEM;
4141 	}
4142 	if (*priv_data_offset + svm_priv_data_size > max_priv_data_size) {
4143 		ret = -EINVAL;
4144 		goto exit;
4145 	}
4146 
4147 	ret = copy_from_user(&criu_svm_md->data, user_priv_ptr + *priv_data_offset,
4148 			     svm_priv_data_size);
4149 	if (ret) {
4150 		ret = -EFAULT;
4151 		goto exit;
4152 	}
4153 	*priv_data_offset += svm_priv_data_size;
4154 
4155 	list_add_tail(&criu_svm_md->list, &svms->criu_svm_metadata_list);
4156 
4157 	return 0;
4158 
4159 
4160 exit:
4161 	kfree(criu_svm_md);
4162 	return ret;
4163 }
4164 
4165 void svm_range_get_info(struct kfd_process *p, uint32_t *num_svm_ranges,
4166 			uint64_t *svm_priv_data_size)
4167 {
4168 	uint64_t total_size, accessibility_size, common_attr_size;
4169 	int nattr_common = 4, nattr_accessibility = 1;
4170 	int num_devices = p->n_pdds;
4171 	struct svm_range_list *svms;
4172 	struct svm_range *prange;
4173 	uint32_t count = 0;
4174 
4175 	*svm_priv_data_size = 0;
4176 
4177 	svms = &p->svms;
4178 
4179 	mutex_lock(&svms->lock);
4180 	list_for_each_entry(prange, &svms->list, list) {
4181 		pr_debug("prange: 0x%p start: 0x%lx\t npages: 0x%llx\t end: 0x%llx\n",
4182 			 prange, prange->start, prange->npages,
4183 			 prange->start + prange->npages - 1);
4184 		count++;
4185 	}
4186 	mutex_unlock(&svms->lock);
4187 
4188 	*num_svm_ranges = count;
4189 	/* Only the accessbility attributes need to be queried for all the gpus
4190 	 * individually, remaining ones are spanned across the entire process
4191 	 * regardless of the various gpu nodes. Of the remaining attributes,
4192 	 * KFD_IOCTL_SVM_ATTR_CLR_FLAGS need not be saved.
4193 	 *
4194 	 * KFD_IOCTL_SVM_ATTR_PREFERRED_LOC
4195 	 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC
4196 	 * KFD_IOCTL_SVM_ATTR_SET_FLAGS
4197 	 * KFD_IOCTL_SVM_ATTR_GRANULARITY
4198 	 *
4199 	 * ** ACCESSBILITY ATTRIBUTES **
4200 	 * (Considered as one, type is altered during query, value is gpuid)
4201 	 * KFD_IOCTL_SVM_ATTR_ACCESS
4202 	 * KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE
4203 	 * KFD_IOCTL_SVM_ATTR_NO_ACCESS
4204 	 */
4205 	if (*num_svm_ranges > 0) {
4206 		common_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4207 			nattr_common;
4208 		accessibility_size = sizeof(struct kfd_ioctl_svm_attribute) *
4209 			nattr_accessibility * num_devices;
4210 
4211 		total_size = sizeof(struct kfd_criu_svm_range_priv_data) +
4212 			common_attr_size + accessibility_size;
4213 
4214 		*svm_priv_data_size = *num_svm_ranges * total_size;
4215 	}
4216 
4217 	pr_debug("num_svm_ranges %u total_priv_size %llu\n", *num_svm_ranges,
4218 		 *svm_priv_data_size);
4219 }
4220 
4221 int kfd_criu_checkpoint_svm(struct kfd_process *p,
4222 			    uint8_t __user *user_priv_data,
4223 			    uint64_t *priv_data_offset)
4224 {
4225 	struct kfd_criu_svm_range_priv_data *svm_priv = NULL;
4226 	struct kfd_ioctl_svm_attribute *query_attr = NULL;
4227 	uint64_t svm_priv_data_size, query_attr_size = 0;
4228 	int index, nattr_common = 4, ret = 0;
4229 	struct svm_range_list *svms;
4230 	int num_devices = p->n_pdds;
4231 	struct svm_range *prange;
4232 	struct mm_struct *mm;
4233 
4234 	svms = &p->svms;
4235 
4236 	mm = get_task_mm(p->lead_thread);
4237 	if (!mm) {
4238 		pr_err("failed to get mm for the target process\n");
4239 		return -ESRCH;
4240 	}
4241 
4242 	query_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4243 				(nattr_common + num_devices);
4244 
4245 	query_attr = kzalloc(query_attr_size, GFP_KERNEL);
4246 	if (!query_attr) {
4247 		ret = -ENOMEM;
4248 		goto exit;
4249 	}
4250 
4251 	query_attr[0].type = KFD_IOCTL_SVM_ATTR_PREFERRED_LOC;
4252 	query_attr[1].type = KFD_IOCTL_SVM_ATTR_PREFETCH_LOC;
4253 	query_attr[2].type = KFD_IOCTL_SVM_ATTR_SET_FLAGS;
4254 	query_attr[3].type = KFD_IOCTL_SVM_ATTR_GRANULARITY;
4255 
4256 	for (index = 0; index < num_devices; index++) {
4257 		struct kfd_process_device *pdd = p->pdds[index];
4258 
4259 		query_attr[index + nattr_common].type =
4260 			KFD_IOCTL_SVM_ATTR_ACCESS;
4261 		query_attr[index + nattr_common].value = pdd->user_gpu_id;
4262 	}
4263 
4264 	svm_priv_data_size = sizeof(*svm_priv) + query_attr_size;
4265 
4266 	svm_priv = kzalloc(svm_priv_data_size, GFP_KERNEL);
4267 	if (!svm_priv) {
4268 		ret = -ENOMEM;
4269 		goto exit_query;
4270 	}
4271 
4272 	index = 0;
4273 	list_for_each_entry(prange, &svms->list, list) {
4274 
4275 		svm_priv->object_type = KFD_CRIU_OBJECT_TYPE_SVM_RANGE;
4276 		svm_priv->start_addr = prange->start;
4277 		svm_priv->size = prange->npages;
4278 		memcpy(&svm_priv->attrs, query_attr, query_attr_size);
4279 		pr_debug("CRIU: prange: 0x%p start: 0x%lx\t npages: 0x%llx end: 0x%llx\t size: 0x%llx\n",
4280 			 prange, prange->start, prange->npages,
4281 			 prange->start + prange->npages - 1,
4282 			 prange->npages * PAGE_SIZE);
4283 
4284 		ret = svm_range_get_attr(p, mm, svm_priv->start_addr,
4285 					 svm_priv->size,
4286 					 (nattr_common + num_devices),
4287 					 svm_priv->attrs);
4288 		if (ret) {
4289 			pr_err("CRIU: failed to obtain range attributes\n");
4290 			goto exit_priv;
4291 		}
4292 
4293 		if (copy_to_user(user_priv_data + *priv_data_offset, svm_priv,
4294 				 svm_priv_data_size)) {
4295 			pr_err("Failed to copy svm priv to user\n");
4296 			ret = -EFAULT;
4297 			goto exit_priv;
4298 		}
4299 
4300 		*priv_data_offset += svm_priv_data_size;
4301 
4302 	}
4303 
4304 
4305 exit_priv:
4306 	kfree(svm_priv);
4307 exit_query:
4308 	kfree(query_attr);
4309 exit:
4310 	mmput(mm);
4311 	return ret;
4312 }
4313 
4314 int
4315 svm_ioctl(struct kfd_process *p, enum kfd_ioctl_svm_op op, uint64_t start,
4316 	  uint64_t size, uint32_t nattrs, struct kfd_ioctl_svm_attribute *attrs)
4317 {
4318 	struct mm_struct *mm = current->mm;
4319 	int r;
4320 
4321 	start >>= PAGE_SHIFT;
4322 	size >>= PAGE_SHIFT;
4323 
4324 	switch (op) {
4325 	case KFD_IOCTL_SVM_OP_SET_ATTR:
4326 		r = svm_range_set_attr(p, mm, start, size, nattrs, attrs);
4327 		break;
4328 	case KFD_IOCTL_SVM_OP_GET_ATTR:
4329 		r = svm_range_get_attr(p, mm, start, size, nattrs, attrs);
4330 		break;
4331 	default:
4332 		r = -EINVAL;
4333 		break;
4334 	}
4335 
4336 	return r;
4337 }
4338