xref: /linux/drivers/gpu/drm/amd/amdkfd/kfd_svm.c (revision 5946dbe1c802efef3b12a4eecab1471f725f4ca9)
1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /*
3  * Copyright 2020-2021 Advanced Micro Devices, Inc.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be included in
13  * all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
19  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
20  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
21  * OTHER DEALINGS IN THE SOFTWARE.
22  */
23 
24 #include <linux/types.h>
25 #include <linux/sched/task.h>
26 #include <linux/dynamic_debug.h>
27 #include <drm/ttm/ttm_tt.h>
28 #include <drm/drm_exec.h>
29 
30 #include "amdgpu_sync.h"
31 #include "amdgpu_object.h"
32 #include "amdgpu_vm.h"
33 #include "amdgpu_hmm.h"
34 #include "amdgpu.h"
35 #include "amdgpu_xgmi.h"
36 #include "amdgpu_reset.h"
37 #include "kfd_priv.h"
38 #include "kfd_svm.h"
39 #include "kfd_migrate.h"
40 #include "kfd_smi_events.h"
41 
42 #ifdef dev_fmt
43 #undef dev_fmt
44 #endif
45 #define dev_fmt(fmt) "kfd_svm: %s: " fmt, __func__
46 
47 #define AMDGPU_SVM_RANGE_RESTORE_DELAY_MS 1
48 
49 /* Long enough to ensure no retry fault comes after svm range is restored and
50  * page table is updated.
51  */
52 #define AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING	(2UL * NSEC_PER_MSEC)
53 #if IS_ENABLED(CONFIG_DYNAMIC_DEBUG)
54 #define dynamic_svm_range_dump(svms) \
55 	_dynamic_func_call_no_desc("svm_range_dump", svm_range_debug_dump, svms)
56 #else
57 #define dynamic_svm_range_dump(svms) \
58 	do { if (0) svm_range_debug_dump(svms); } while (0)
59 #endif
60 
61 /* Giant svm range split into smaller ranges based on this, it is decided using
62  * minimum of all dGPU/APU 1/32 VRAM size, between 2MB to 1GB and alignment to
63  * power of 2MB.
64  */
65 static uint64_t max_svm_range_pages;
66 
67 struct criu_svm_metadata {
68 	struct list_head list;
69 	struct kfd_criu_svm_range_priv_data data;
70 };
71 
72 static void svm_range_evict_svm_bo_worker(struct work_struct *work);
73 static bool
74 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
75 				    const struct mmu_notifier_range *range,
76 				    unsigned long cur_seq);
77 static int
78 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
79 		   uint64_t *bo_s, uint64_t *bo_l);
80 static const struct mmu_interval_notifier_ops svm_range_mn_ops = {
81 	.invalidate = svm_range_cpu_invalidate_pagetables,
82 };
83 
84 /**
85  * svm_range_unlink - unlink svm_range from lists and interval tree
86  * @prange: svm range structure to be removed
87  *
88  * Remove the svm_range from the svms and svm_bo lists and the svms
89  * interval tree.
90  *
91  * Context: The caller must hold svms->lock
92  */
93 static void svm_range_unlink(struct svm_range *prange)
94 {
95 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
96 		 prange, prange->start, prange->last);
97 
98 	if (prange->svm_bo) {
99 		spin_lock(&prange->svm_bo->list_lock);
100 		list_del(&prange->svm_bo_list);
101 		spin_unlock(&prange->svm_bo->list_lock);
102 	}
103 
104 	list_del(&prange->list);
105 	if (prange->it_node.start != 0 && prange->it_node.last != 0)
106 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
107 }
108 
109 static void
110 svm_range_add_notifier_locked(struct mm_struct *mm, struct svm_range *prange)
111 {
112 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
113 		 prange, prange->start, prange->last);
114 
115 	mmu_interval_notifier_insert_locked(&prange->notifier, mm,
116 				     prange->start << PAGE_SHIFT,
117 				     prange->npages << PAGE_SHIFT,
118 				     &svm_range_mn_ops);
119 }
120 
121 /**
122  * svm_range_add_to_svms - add svm range to svms
123  * @prange: svm range structure to be added
124  *
125  * Add the svm range to svms interval tree and link list
126  *
127  * Context: The caller must hold svms->lock
128  */
129 static void svm_range_add_to_svms(struct svm_range *prange)
130 {
131 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms,
132 		 prange, prange->start, prange->last);
133 
134 	list_move_tail(&prange->list, &prange->svms->list);
135 	prange->it_node.start = prange->start;
136 	prange->it_node.last = prange->last;
137 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
138 }
139 
140 static void svm_range_remove_notifier(struct svm_range *prange)
141 {
142 	pr_debug("remove notifier svms 0x%p prange 0x%p [0x%lx 0x%lx]\n",
143 		 prange->svms, prange,
144 		 prange->notifier.interval_tree.start >> PAGE_SHIFT,
145 		 prange->notifier.interval_tree.last >> PAGE_SHIFT);
146 
147 	if (prange->notifier.interval_tree.start != 0 &&
148 	    prange->notifier.interval_tree.last != 0)
149 		mmu_interval_notifier_remove(&prange->notifier);
150 }
151 
152 static bool
153 svm_is_valid_dma_mapping_addr(struct device *dev, dma_addr_t dma_addr)
154 {
155 	return dma_addr && !dma_mapping_error(dev, dma_addr) &&
156 	       !(dma_addr & SVM_RANGE_VRAM_DOMAIN);
157 }
158 
159 static int
160 svm_range_dma_map_dev(struct amdgpu_device *adev, struct svm_range *prange,
161 		      unsigned long offset, unsigned long npages,
162 		      unsigned long *hmm_pfns, uint32_t gpuidx)
163 {
164 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
165 	dma_addr_t *addr = prange->dma_addr[gpuidx];
166 	struct device *dev = adev->dev;
167 	struct page *page;
168 	int i, r;
169 
170 	if (!addr) {
171 		addr = kvcalloc(prange->npages, sizeof(*addr), GFP_KERNEL);
172 		if (!addr)
173 			return -ENOMEM;
174 		prange->dma_addr[gpuidx] = addr;
175 	}
176 
177 	addr += offset;
178 	for (i = 0; i < npages; i++) {
179 		if (svm_is_valid_dma_mapping_addr(dev, addr[i]))
180 			dma_unmap_page(dev, addr[i], PAGE_SIZE, dir);
181 
182 		page = hmm_pfn_to_page(hmm_pfns[i]);
183 		if (is_zone_device_page(page)) {
184 			struct amdgpu_device *bo_adev = prange->svm_bo->node->adev;
185 
186 			addr[i] = (hmm_pfns[i] << PAGE_SHIFT) +
187 				   bo_adev->vm_manager.vram_base_offset -
188 				   bo_adev->kfd.pgmap.range.start;
189 			addr[i] |= SVM_RANGE_VRAM_DOMAIN;
190 			pr_debug_ratelimited("vram address: 0x%llx\n", addr[i]);
191 			continue;
192 		}
193 		addr[i] = dma_map_page(dev, page, 0, PAGE_SIZE, dir);
194 		r = dma_mapping_error(dev, addr[i]);
195 		if (r) {
196 			dev_err(dev, "failed %d dma_map_page\n", r);
197 			return r;
198 		}
199 		pr_debug_ratelimited("dma mapping 0x%llx for page addr 0x%lx\n",
200 				     addr[i] >> PAGE_SHIFT, page_to_pfn(page));
201 	}
202 
203 	return 0;
204 }
205 
206 static int
207 svm_range_dma_map(struct svm_range *prange, unsigned long *bitmap,
208 		  unsigned long offset, unsigned long npages,
209 		  unsigned long *hmm_pfns)
210 {
211 	struct kfd_process *p;
212 	uint32_t gpuidx;
213 	int r;
214 
215 	p = container_of(prange->svms, struct kfd_process, svms);
216 
217 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
218 		struct kfd_process_device *pdd;
219 
220 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
221 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
222 		if (!pdd) {
223 			pr_debug("failed to find device idx %d\n", gpuidx);
224 			return -EINVAL;
225 		}
226 
227 		r = svm_range_dma_map_dev(pdd->dev->adev, prange, offset, npages,
228 					  hmm_pfns, gpuidx);
229 		if (r)
230 			break;
231 	}
232 
233 	return r;
234 }
235 
236 void svm_range_dma_unmap_dev(struct device *dev, dma_addr_t *dma_addr,
237 			 unsigned long offset, unsigned long npages)
238 {
239 	enum dma_data_direction dir = DMA_BIDIRECTIONAL;
240 	int i;
241 
242 	if (!dma_addr)
243 		return;
244 
245 	for (i = offset; i < offset + npages; i++) {
246 		if (!svm_is_valid_dma_mapping_addr(dev, dma_addr[i]))
247 			continue;
248 		pr_debug_ratelimited("unmap 0x%llx\n", dma_addr[i] >> PAGE_SHIFT);
249 		dma_unmap_page(dev, dma_addr[i], PAGE_SIZE, dir);
250 		dma_addr[i] = 0;
251 	}
252 }
253 
254 void svm_range_dma_unmap(struct svm_range *prange)
255 {
256 	struct kfd_process_device *pdd;
257 	dma_addr_t *dma_addr;
258 	struct device *dev;
259 	struct kfd_process *p;
260 	uint32_t gpuidx;
261 
262 	p = container_of(prange->svms, struct kfd_process, svms);
263 
264 	for (gpuidx = 0; gpuidx < MAX_GPU_INSTANCE; gpuidx++) {
265 		dma_addr = prange->dma_addr[gpuidx];
266 		if (!dma_addr)
267 			continue;
268 
269 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
270 		if (!pdd) {
271 			pr_debug("failed to find device idx %d\n", gpuidx);
272 			continue;
273 		}
274 		dev = &pdd->dev->adev->pdev->dev;
275 
276 		svm_range_dma_unmap_dev(dev, dma_addr, 0, prange->npages);
277 	}
278 }
279 
280 static void svm_range_free(struct svm_range *prange, bool do_unmap)
281 {
282 	uint64_t size = (prange->last - prange->start + 1) << PAGE_SHIFT;
283 	struct kfd_process *p = container_of(prange->svms, struct kfd_process, svms);
284 	uint32_t gpuidx;
285 
286 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx]\n", prange->svms, prange,
287 		 prange->start, prange->last);
288 
289 	svm_range_vram_node_free(prange);
290 	if (do_unmap)
291 		svm_range_dma_unmap(prange);
292 
293 	if (do_unmap && !p->xnack_enabled) {
294 		pr_debug("unreserve prange 0x%p size: 0x%llx\n", prange, size);
295 		amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
296 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
297 	}
298 
299 	/* free dma_addr array for each gpu */
300 	for (gpuidx = 0; gpuidx < MAX_GPU_INSTANCE; gpuidx++) {
301 		if (prange->dma_addr[gpuidx]) {
302 			kvfree(prange->dma_addr[gpuidx]);
303 			prange->dma_addr[gpuidx] = NULL;
304 		}
305 	}
306 
307 	mutex_destroy(&prange->lock);
308 	mutex_destroy(&prange->migrate_mutex);
309 	kfree(prange);
310 }
311 
312 static void
313 svm_range_set_default_attributes(struct svm_range_list *svms, int32_t *location,
314 				 int32_t *prefetch_loc, uint8_t *granularity,
315 				 uint32_t *flags)
316 {
317 	*location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
318 	*prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
319 	*granularity = svms->default_granularity;
320 	*flags =
321 		KFD_IOCTL_SVM_FLAG_HOST_ACCESS | KFD_IOCTL_SVM_FLAG_COHERENT;
322 }
323 
324 static struct
325 svm_range *svm_range_new(struct svm_range_list *svms, uint64_t start,
326 			 uint64_t last, bool update_mem_usage)
327 {
328 	uint64_t size = last - start + 1;
329 	struct svm_range *prange;
330 	struct kfd_process *p;
331 
332 	prange = kzalloc(sizeof(*prange), GFP_KERNEL);
333 	if (!prange)
334 		return NULL;
335 
336 	p = container_of(svms, struct kfd_process, svms);
337 	if (!p->xnack_enabled && update_mem_usage &&
338 	    amdgpu_amdkfd_reserve_mem_limit(NULL, size << PAGE_SHIFT,
339 				    KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0)) {
340 		pr_info("SVM mapping failed, exceeds resident system memory limit\n");
341 		kfree(prange);
342 		return NULL;
343 	}
344 	prange->npages = size;
345 	prange->svms = svms;
346 	prange->start = start;
347 	prange->last = last;
348 	INIT_LIST_HEAD(&prange->list);
349 	INIT_LIST_HEAD(&prange->update_list);
350 	INIT_LIST_HEAD(&prange->svm_bo_list);
351 	INIT_LIST_HEAD(&prange->deferred_list);
352 	INIT_LIST_HEAD(&prange->child_list);
353 	atomic_set(&prange->invalid, 0);
354 	prange->validate_timestamp = 0;
355 	prange->vram_pages = 0;
356 	mutex_init(&prange->migrate_mutex);
357 	mutex_init(&prange->lock);
358 
359 	if (p->xnack_enabled)
360 		bitmap_copy(prange->bitmap_access, svms->bitmap_supported,
361 			    MAX_GPU_INSTANCE);
362 
363 	svm_range_set_default_attributes(svms, &prange->preferred_loc,
364 					 &prange->prefetch_loc,
365 					 &prange->granularity, &prange->flags);
366 
367 	pr_debug("svms 0x%p [0x%llx 0x%llx]\n", svms, start, last);
368 
369 	return prange;
370 }
371 
372 static bool svm_bo_ref_unless_zero(struct svm_range_bo *svm_bo)
373 {
374 	if (!svm_bo || !kref_get_unless_zero(&svm_bo->kref))
375 		return false;
376 
377 	return true;
378 }
379 
380 static void svm_range_bo_release(struct kref *kref)
381 {
382 	struct svm_range_bo *svm_bo;
383 
384 	svm_bo = container_of(kref, struct svm_range_bo, kref);
385 	pr_debug("svm_bo 0x%p\n", svm_bo);
386 
387 	spin_lock(&svm_bo->list_lock);
388 	while (!list_empty(&svm_bo->range_list)) {
389 		struct svm_range *prange =
390 				list_first_entry(&svm_bo->range_list,
391 						struct svm_range, svm_bo_list);
392 		/* list_del_init tells a concurrent svm_range_vram_node_new when
393 		 * it's safe to reuse the svm_bo pointer and svm_bo_list head.
394 		 */
395 		list_del_init(&prange->svm_bo_list);
396 		spin_unlock(&svm_bo->list_lock);
397 
398 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
399 			 prange->start, prange->last);
400 		mutex_lock(&prange->lock);
401 		prange->svm_bo = NULL;
402 		/* prange should not hold vram page now */
403 		WARN_ONCE(prange->actual_loc, "prange should not hold vram page");
404 		mutex_unlock(&prange->lock);
405 
406 		spin_lock(&svm_bo->list_lock);
407 	}
408 	spin_unlock(&svm_bo->list_lock);
409 
410 	if (mmget_not_zero(svm_bo->eviction_fence->mm)) {
411 		struct kfd_process_device *pdd;
412 		struct kfd_process *p;
413 		struct mm_struct *mm;
414 
415 		mm = svm_bo->eviction_fence->mm;
416 		/*
417 		 * The forked child process takes svm_bo device pages ref, svm_bo could be
418 		 * released after parent process is gone.
419 		 */
420 		p = kfd_lookup_process_by_mm(mm);
421 		if (p) {
422 			pdd = kfd_get_process_device_data(svm_bo->node, p);
423 			if (pdd)
424 				atomic64_sub(amdgpu_bo_size(svm_bo->bo), &pdd->vram_usage);
425 			kfd_unref_process(p);
426 		}
427 		mmput(mm);
428 	}
429 
430 	if (!dma_fence_is_signaled(&svm_bo->eviction_fence->base))
431 		/* We're not in the eviction worker. Signal the fence. */
432 		dma_fence_signal(&svm_bo->eviction_fence->base);
433 	dma_fence_put(&svm_bo->eviction_fence->base);
434 	amdgpu_bo_unref(&svm_bo->bo);
435 	kfree(svm_bo);
436 }
437 
438 static void svm_range_bo_wq_release(struct work_struct *work)
439 {
440 	struct svm_range_bo *svm_bo;
441 
442 	svm_bo = container_of(work, struct svm_range_bo, release_work);
443 	svm_range_bo_release(&svm_bo->kref);
444 }
445 
446 static void svm_range_bo_release_async(struct kref *kref)
447 {
448 	struct svm_range_bo *svm_bo;
449 
450 	svm_bo = container_of(kref, struct svm_range_bo, kref);
451 	pr_debug("svm_bo 0x%p\n", svm_bo);
452 	INIT_WORK(&svm_bo->release_work, svm_range_bo_wq_release);
453 	schedule_work(&svm_bo->release_work);
454 }
455 
456 void svm_range_bo_unref_async(struct svm_range_bo *svm_bo)
457 {
458 	kref_put(&svm_bo->kref, svm_range_bo_release_async);
459 }
460 
461 static void svm_range_bo_unref(struct svm_range_bo *svm_bo)
462 {
463 	if (svm_bo)
464 		kref_put(&svm_bo->kref, svm_range_bo_release);
465 }
466 
467 static bool
468 svm_range_validate_svm_bo(struct kfd_node *node, struct svm_range *prange)
469 {
470 	mutex_lock(&prange->lock);
471 	if (!prange->svm_bo) {
472 		mutex_unlock(&prange->lock);
473 		return false;
474 	}
475 	if (prange->ttm_res) {
476 		/* We still have a reference, all is well */
477 		mutex_unlock(&prange->lock);
478 		return true;
479 	}
480 	if (svm_bo_ref_unless_zero(prange->svm_bo)) {
481 		/*
482 		 * Migrate from GPU to GPU, remove range from source svm_bo->node
483 		 * range list, and return false to allocate svm_bo from destination
484 		 * node.
485 		 */
486 		if (prange->svm_bo->node != node) {
487 			mutex_unlock(&prange->lock);
488 
489 			spin_lock(&prange->svm_bo->list_lock);
490 			list_del_init(&prange->svm_bo_list);
491 			spin_unlock(&prange->svm_bo->list_lock);
492 
493 			svm_range_bo_unref(prange->svm_bo);
494 			return false;
495 		}
496 		if (READ_ONCE(prange->svm_bo->evicting)) {
497 			struct dma_fence *f;
498 			struct svm_range_bo *svm_bo;
499 			/* The BO is getting evicted,
500 			 * we need to get a new one
501 			 */
502 			mutex_unlock(&prange->lock);
503 			svm_bo = prange->svm_bo;
504 			f = dma_fence_get(&svm_bo->eviction_fence->base);
505 			svm_range_bo_unref(prange->svm_bo);
506 			/* wait for the fence to avoid long spin-loop
507 			 * at list_empty_careful
508 			 */
509 			dma_fence_wait(f, false);
510 			dma_fence_put(f);
511 		} else {
512 			/* The BO was still around and we got
513 			 * a new reference to it
514 			 */
515 			mutex_unlock(&prange->lock);
516 			pr_debug("reuse old bo svms 0x%p [0x%lx 0x%lx]\n",
517 				 prange->svms, prange->start, prange->last);
518 
519 			prange->ttm_res = prange->svm_bo->bo->tbo.resource;
520 			return true;
521 		}
522 
523 	} else {
524 		mutex_unlock(&prange->lock);
525 	}
526 
527 	/* We need a new svm_bo. Spin-loop to wait for concurrent
528 	 * svm_range_bo_release to finish removing this range from
529 	 * its range list and set prange->svm_bo to null. After this,
530 	 * it is safe to reuse the svm_bo pointer and svm_bo_list head.
531 	 */
532 	while (!list_empty_careful(&prange->svm_bo_list) || prange->svm_bo)
533 		cond_resched();
534 
535 	return false;
536 }
537 
538 static struct svm_range_bo *svm_range_bo_new(void)
539 {
540 	struct svm_range_bo *svm_bo;
541 
542 	svm_bo = kzalloc(sizeof(*svm_bo), GFP_KERNEL);
543 	if (!svm_bo)
544 		return NULL;
545 
546 	kref_init(&svm_bo->kref);
547 	INIT_LIST_HEAD(&svm_bo->range_list);
548 	spin_lock_init(&svm_bo->list_lock);
549 
550 	return svm_bo;
551 }
552 
553 int
554 svm_range_vram_node_new(struct kfd_node *node, struct svm_range *prange,
555 			bool clear)
556 {
557 	struct kfd_process_device *pdd;
558 	struct amdgpu_bo_param bp;
559 	struct svm_range_bo *svm_bo;
560 	struct amdgpu_bo_user *ubo;
561 	struct amdgpu_bo *bo;
562 	struct kfd_process *p;
563 	struct mm_struct *mm;
564 	int r;
565 
566 	p = container_of(prange->svms, struct kfd_process, svms);
567 	pr_debug("process pid: %d svms 0x%p [0x%lx 0x%lx]\n",
568 		 p->lead_thread->pid, prange->svms,
569 		 prange->start, prange->last);
570 
571 	if (svm_range_validate_svm_bo(node, prange))
572 		return 0;
573 
574 	svm_bo = svm_range_bo_new();
575 	if (!svm_bo) {
576 		pr_debug("failed to alloc svm bo\n");
577 		return -ENOMEM;
578 	}
579 	mm = get_task_mm(p->lead_thread);
580 	if (!mm) {
581 		pr_debug("failed to get mm\n");
582 		kfree(svm_bo);
583 		return -ESRCH;
584 	}
585 	svm_bo->node = node;
586 	svm_bo->eviction_fence =
587 		amdgpu_amdkfd_fence_create(dma_fence_context_alloc(1),
588 					   mm,
589 					   svm_bo, p->context_id);
590 	mmput(mm);
591 	INIT_WORK(&svm_bo->eviction_work, svm_range_evict_svm_bo_worker);
592 	svm_bo->evicting = 0;
593 	memset(&bp, 0, sizeof(bp));
594 	bp.size = prange->npages * PAGE_SIZE;
595 	bp.byte_align = PAGE_SIZE;
596 	bp.domain = AMDGPU_GEM_DOMAIN_VRAM;
597 	bp.flags = AMDGPU_GEM_CREATE_NO_CPU_ACCESS;
598 	bp.flags |= clear ? AMDGPU_GEM_CREATE_VRAM_CLEARED : 0;
599 	bp.flags |= AMDGPU_GEM_CREATE_DISCARDABLE;
600 	bp.type = ttm_bo_type_device;
601 	bp.resv = NULL;
602 	if (node->xcp)
603 		bp.xcp_id_plus1 = node->xcp->id + 1;
604 
605 	r = amdgpu_bo_create_user(node->adev, &bp, &ubo);
606 	if (r) {
607 		pr_debug("failed %d to create bo\n", r);
608 		goto create_bo_failed;
609 	}
610 	bo = &ubo->bo;
611 
612 	pr_debug("alloc bo at offset 0x%lx size 0x%lx on partition %d\n",
613 		 bo->tbo.resource->start << PAGE_SHIFT, bp.size,
614 		 bp.xcp_id_plus1 - 1);
615 
616 	r = amdgpu_bo_reserve(bo, true);
617 	if (r) {
618 		pr_debug("failed %d to reserve bo\n", r);
619 		goto reserve_bo_failed;
620 	}
621 
622 	if (clear) {
623 		r = amdgpu_bo_sync_wait(bo, AMDGPU_FENCE_OWNER_KFD, false);
624 		if (r) {
625 			pr_debug("failed %d to sync bo\n", r);
626 			amdgpu_bo_unreserve(bo);
627 			goto reserve_bo_failed;
628 		}
629 	}
630 
631 	r = dma_resv_reserve_fences(bo->tbo.base.resv, 1);
632 	if (r) {
633 		pr_debug("failed %d to reserve bo\n", r);
634 		amdgpu_bo_unreserve(bo);
635 		goto reserve_bo_failed;
636 	}
637 	amdgpu_bo_fence(bo, &svm_bo->eviction_fence->base, true);
638 
639 	amdgpu_bo_unreserve(bo);
640 
641 	svm_bo->bo = bo;
642 	prange->svm_bo = svm_bo;
643 	prange->ttm_res = bo->tbo.resource;
644 	prange->offset = 0;
645 
646 	spin_lock(&svm_bo->list_lock);
647 	list_add(&prange->svm_bo_list, &svm_bo->range_list);
648 	spin_unlock(&svm_bo->list_lock);
649 
650 	pdd = svm_range_get_pdd_by_node(prange, node);
651 	if (pdd)
652 		atomic64_add(amdgpu_bo_size(bo), &pdd->vram_usage);
653 
654 	return 0;
655 
656 reserve_bo_failed:
657 	amdgpu_bo_unref(&bo);
658 create_bo_failed:
659 	dma_fence_put(&svm_bo->eviction_fence->base);
660 	kfree(svm_bo);
661 	prange->ttm_res = NULL;
662 
663 	return r;
664 }
665 
666 void svm_range_vram_node_free(struct svm_range *prange)
667 {
668 	/* serialize prange->svm_bo unref */
669 	mutex_lock(&prange->lock);
670 	/* prange->svm_bo has not been unref */
671 	if (prange->ttm_res) {
672 		prange->ttm_res = NULL;
673 		mutex_unlock(&prange->lock);
674 		svm_range_bo_unref(prange->svm_bo);
675 	} else
676 		mutex_unlock(&prange->lock);
677 }
678 
679 struct kfd_node *
680 svm_range_get_node_by_id(struct svm_range *prange, uint32_t gpu_id)
681 {
682 	struct kfd_process *p;
683 	struct kfd_process_device *pdd;
684 
685 	p = container_of(prange->svms, struct kfd_process, svms);
686 	pdd = kfd_process_device_data_by_id(p, gpu_id);
687 	if (!pdd) {
688 		pr_debug("failed to get kfd process device by id 0x%x\n", gpu_id);
689 		return NULL;
690 	}
691 
692 	return pdd->dev;
693 }
694 
695 struct kfd_process_device *
696 svm_range_get_pdd_by_node(struct svm_range *prange, struct kfd_node *node)
697 {
698 	struct kfd_process *p;
699 
700 	p = container_of(prange->svms, struct kfd_process, svms);
701 
702 	return kfd_get_process_device_data(node, p);
703 }
704 
705 static int svm_range_bo_validate(void *param, struct amdgpu_bo *bo)
706 {
707 	struct ttm_operation_ctx ctx = { false, false };
708 
709 	amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_VRAM);
710 
711 	return ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
712 }
713 
714 static int
715 svm_range_check_attr(struct kfd_process *p,
716 		     uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
717 {
718 	uint32_t i;
719 
720 	for (i = 0; i < nattr; i++) {
721 		uint32_t val = attrs[i].value;
722 		int gpuidx = MAX_GPU_INSTANCE;
723 
724 		switch (attrs[i].type) {
725 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
726 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM &&
727 			    val != KFD_IOCTL_SVM_LOCATION_UNDEFINED)
728 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
729 			break;
730 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
731 			if (val != KFD_IOCTL_SVM_LOCATION_SYSMEM)
732 				gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
733 			break;
734 		case KFD_IOCTL_SVM_ATTR_ACCESS:
735 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
736 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
737 			gpuidx = kfd_process_gpuidx_from_gpuid(p, val);
738 			break;
739 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
740 			break;
741 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
742 			break;
743 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
744 			break;
745 		default:
746 			pr_debug("unknown attr type 0x%x\n", attrs[i].type);
747 			return -EINVAL;
748 		}
749 
750 		if (gpuidx < 0) {
751 			pr_debug("no GPU 0x%x found\n", val);
752 			return -EINVAL;
753 		} else if (gpuidx < MAX_GPU_INSTANCE &&
754 			   !test_bit(gpuidx, p->svms.bitmap_supported)) {
755 			pr_debug("GPU 0x%x not supported\n", val);
756 			return -EINVAL;
757 		}
758 	}
759 
760 	return 0;
761 }
762 
763 static void
764 svm_range_apply_attrs(struct kfd_process *p, struct svm_range *prange,
765 		      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
766 		      bool *update_mapping)
767 {
768 	uint32_t i;
769 	int gpuidx;
770 
771 	for (i = 0; i < nattr; i++) {
772 		switch (attrs[i].type) {
773 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
774 			prange->preferred_loc = attrs[i].value;
775 			break;
776 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
777 			prange->prefetch_loc = attrs[i].value;
778 			break;
779 		case KFD_IOCTL_SVM_ATTR_ACCESS:
780 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
781 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
782 			if (!p->xnack_enabled)
783 				*update_mapping = true;
784 
785 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
786 							       attrs[i].value);
787 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
788 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
789 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
790 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
791 				bitmap_set(prange->bitmap_access, gpuidx, 1);
792 				bitmap_clear(prange->bitmap_aip, gpuidx, 1);
793 			} else {
794 				bitmap_clear(prange->bitmap_access, gpuidx, 1);
795 				bitmap_set(prange->bitmap_aip, gpuidx, 1);
796 			}
797 			break;
798 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
799 			*update_mapping = true;
800 			prange->flags |= attrs[i].value;
801 			break;
802 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
803 			*update_mapping = true;
804 			prange->flags &= ~attrs[i].value;
805 			break;
806 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
807 			prange->granularity = min_t(uint32_t, attrs[i].value, 0x3F);
808 			break;
809 		default:
810 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
811 		}
812 	}
813 }
814 
815 static bool
816 svm_range_is_same_attrs(struct kfd_process *p, struct svm_range *prange,
817 			uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs)
818 {
819 	uint32_t i;
820 	int gpuidx;
821 
822 	for (i = 0; i < nattr; i++) {
823 		switch (attrs[i].type) {
824 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
825 			if (prange->preferred_loc != attrs[i].value)
826 				return false;
827 			break;
828 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
829 			/* Prefetch should always trigger a migration even
830 			 * if the value of the attribute didn't change.
831 			 */
832 			return false;
833 		case KFD_IOCTL_SVM_ATTR_ACCESS:
834 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
835 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
836 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
837 							       attrs[i].value);
838 			if (attrs[i].type == KFD_IOCTL_SVM_ATTR_NO_ACCESS) {
839 				if (test_bit(gpuidx, prange->bitmap_access) ||
840 				    test_bit(gpuidx, prange->bitmap_aip))
841 					return false;
842 			} else if (attrs[i].type == KFD_IOCTL_SVM_ATTR_ACCESS) {
843 				if (!test_bit(gpuidx, prange->bitmap_access))
844 					return false;
845 			} else {
846 				if (!test_bit(gpuidx, prange->bitmap_aip))
847 					return false;
848 			}
849 			break;
850 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
851 			if ((prange->flags & attrs[i].value) != attrs[i].value)
852 				return false;
853 			break;
854 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
855 			if ((prange->flags & attrs[i].value) != 0)
856 				return false;
857 			break;
858 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
859 			if (prange->granularity != attrs[i].value)
860 				return false;
861 			break;
862 		default:
863 			WARN_ONCE(1, "svm_range_check_attrs wasn't called?");
864 		}
865 	}
866 
867 	return true;
868 }
869 
870 /**
871  * svm_range_debug_dump - print all range information from svms
872  * @svms: svm range list header
873  *
874  * debug output svm range start, end, prefetch location from svms
875  * interval tree and link list
876  *
877  * Context: The caller must hold svms->lock
878  */
879 static void svm_range_debug_dump(struct svm_range_list *svms)
880 {
881 	struct interval_tree_node *node;
882 	struct svm_range *prange;
883 
884 	pr_debug("dump svms 0x%p list\n", svms);
885 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
886 
887 	list_for_each_entry(prange, &svms->list, list) {
888 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
889 			 prange, prange->start, prange->npages,
890 			 prange->start + prange->npages - 1,
891 			 prange->actual_loc);
892 	}
893 
894 	pr_debug("dump svms 0x%p interval tree\n", svms);
895 	pr_debug("range\tstart\tpage\tend\t\tlocation\n");
896 	node = interval_tree_iter_first(&svms->objects, 0, ~0ULL);
897 	while (node) {
898 		prange = container_of(node, struct svm_range, it_node);
899 		pr_debug("0x%p 0x%lx\t0x%llx\t0x%llx\t0x%x\n",
900 			 prange, prange->start, prange->npages,
901 			 prange->start + prange->npages - 1,
902 			 prange->actual_loc);
903 		node = interval_tree_iter_next(node, 0, ~0ULL);
904 	}
905 }
906 
907 static void *
908 svm_range_copy_array(void *psrc, size_t size, uint64_t num_elements,
909 		     uint64_t offset, uint64_t *vram_pages)
910 {
911 	unsigned char *src = (unsigned char *)psrc + offset;
912 	unsigned char *dst;
913 	uint64_t i;
914 
915 	dst = kvmalloc_array(num_elements, size, GFP_KERNEL);
916 	if (!dst)
917 		return NULL;
918 
919 	if (!vram_pages) {
920 		memcpy(dst, src, num_elements * size);
921 		return (void *)dst;
922 	}
923 
924 	*vram_pages = 0;
925 	for (i = 0; i < num_elements; i++) {
926 		dma_addr_t *temp;
927 		temp = (dma_addr_t *)dst + i;
928 		*temp = *((dma_addr_t *)src + i);
929 		if (*temp&SVM_RANGE_VRAM_DOMAIN)
930 			(*vram_pages)++;
931 	}
932 
933 	return (void *)dst;
934 }
935 
936 static int
937 svm_range_copy_dma_addrs(struct svm_range *dst, struct svm_range *src)
938 {
939 	int i;
940 
941 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
942 		if (!src->dma_addr[i])
943 			continue;
944 		dst->dma_addr[i] = svm_range_copy_array(src->dma_addr[i],
945 					sizeof(*src->dma_addr[i]), src->npages, 0, NULL);
946 		if (!dst->dma_addr[i])
947 			return -ENOMEM;
948 	}
949 
950 	return 0;
951 }
952 
953 static int
954 svm_range_split_array(void *ppnew, void *ppold, size_t size,
955 		      uint64_t old_start, uint64_t old_n,
956 		      uint64_t new_start, uint64_t new_n, uint64_t *new_vram_pages)
957 {
958 	unsigned char *new, *old, *pold;
959 	uint64_t d;
960 
961 	if (!ppold)
962 		return 0;
963 	pold = *(unsigned char **)ppold;
964 	if (!pold)
965 		return 0;
966 
967 	d = (new_start - old_start) * size;
968 	/* get dma addr array for new range and calculte its vram page number */
969 	new = svm_range_copy_array(pold, size, new_n, d, new_vram_pages);
970 	if (!new)
971 		return -ENOMEM;
972 	d = (new_start == old_start) ? new_n * size : 0;
973 	old = svm_range_copy_array(pold, size, old_n, d, NULL);
974 	if (!old) {
975 		kvfree(new);
976 		return -ENOMEM;
977 	}
978 	kvfree(pold);
979 	*(void **)ppold = old;
980 	*(void **)ppnew = new;
981 
982 	return 0;
983 }
984 
985 static int
986 svm_range_split_pages(struct svm_range *new, struct svm_range *old,
987 		      uint64_t start, uint64_t last)
988 {
989 	uint64_t npages = last - start + 1;
990 	int i, r;
991 
992 	for (i = 0; i < MAX_GPU_INSTANCE; i++) {
993 		r = svm_range_split_array(&new->dma_addr[i], &old->dma_addr[i],
994 					  sizeof(*old->dma_addr[i]), old->start,
995 					  npages, new->start, new->npages,
996 					  old->actual_loc ? &new->vram_pages : NULL);
997 		if (r)
998 			return r;
999 	}
1000 	if (old->actual_loc)
1001 		old->vram_pages -= new->vram_pages;
1002 
1003 	return 0;
1004 }
1005 
1006 static int
1007 svm_range_split_nodes(struct svm_range *new, struct svm_range *old,
1008 		      uint64_t start, uint64_t last)
1009 {
1010 	uint64_t npages = last - start + 1;
1011 
1012 	pr_debug("svms 0x%p new prange 0x%p start 0x%lx [0x%llx 0x%llx]\n",
1013 		 new->svms, new, new->start, start, last);
1014 
1015 	if (new->start == old->start) {
1016 		new->offset = old->offset;
1017 		old->offset += new->npages;
1018 	} else {
1019 		new->offset = old->offset + npages;
1020 	}
1021 
1022 	new->svm_bo = svm_range_bo_ref(old->svm_bo);
1023 	new->ttm_res = old->ttm_res;
1024 
1025 	spin_lock(&new->svm_bo->list_lock);
1026 	list_add(&new->svm_bo_list, &new->svm_bo->range_list);
1027 	spin_unlock(&new->svm_bo->list_lock);
1028 
1029 	return 0;
1030 }
1031 
1032 /**
1033  * svm_range_split_adjust - split range and adjust
1034  *
1035  * @new: new range
1036  * @old: the old range
1037  * @start: the old range adjust to start address in pages
1038  * @last: the old range adjust to last address in pages
1039  *
1040  * Copy system memory dma_addr or vram ttm_res in old range to new
1041  * range from new_start up to size new->npages, the remaining old range is from
1042  * start to last
1043  *
1044  * Return:
1045  * 0 - OK, -ENOMEM - out of memory
1046  */
1047 static int
1048 svm_range_split_adjust(struct svm_range *new, struct svm_range *old,
1049 		      uint64_t start, uint64_t last)
1050 {
1051 	int r;
1052 
1053 	pr_debug("svms 0x%p new 0x%lx old [0x%lx 0x%lx] => [0x%llx 0x%llx]\n",
1054 		 new->svms, new->start, old->start, old->last, start, last);
1055 
1056 	if (new->start < old->start ||
1057 	    new->last > old->last) {
1058 		WARN_ONCE(1, "invalid new range start or last\n");
1059 		return -EINVAL;
1060 	}
1061 
1062 	r = svm_range_split_pages(new, old, start, last);
1063 	if (r)
1064 		return r;
1065 
1066 	if (old->actual_loc && old->ttm_res) {
1067 		r = svm_range_split_nodes(new, old, start, last);
1068 		if (r)
1069 			return r;
1070 	}
1071 
1072 	old->npages = last - start + 1;
1073 	old->start = start;
1074 	old->last = last;
1075 	new->flags = old->flags;
1076 	new->preferred_loc = old->preferred_loc;
1077 	new->prefetch_loc = old->prefetch_loc;
1078 	new->actual_loc = old->actual_loc;
1079 	new->granularity = old->granularity;
1080 	new->mapped_to_gpu = old->mapped_to_gpu;
1081 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
1082 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
1083 	atomic_set(&new->queue_refcount, atomic_read(&old->queue_refcount));
1084 
1085 	return 0;
1086 }
1087 
1088 /**
1089  * svm_range_split - split a range in 2 ranges
1090  *
1091  * @prange: the svm range to split
1092  * @start: the remaining range start address in pages
1093  * @last: the remaining range last address in pages
1094  * @new: the result new range generated
1095  *
1096  * Two cases only:
1097  * case 1: if start == prange->start
1098  *         prange ==> prange[start, last]
1099  *         new range [last + 1, prange->last]
1100  *
1101  * case 2: if last == prange->last
1102  *         prange ==> prange[start, last]
1103  *         new range [prange->start, start - 1]
1104  *
1105  * Return:
1106  * 0 - OK, -ENOMEM - out of memory, -EINVAL - invalid start, last
1107  */
1108 static int
1109 svm_range_split(struct svm_range *prange, uint64_t start, uint64_t last,
1110 		struct svm_range **new)
1111 {
1112 	uint64_t old_start = prange->start;
1113 	uint64_t old_last = prange->last;
1114 	struct svm_range_list *svms;
1115 	int r = 0;
1116 
1117 	pr_debug("svms 0x%p [0x%llx 0x%llx] to [0x%llx 0x%llx]\n", prange->svms,
1118 		 old_start, old_last, start, last);
1119 
1120 	if (old_start != start && old_last != last)
1121 		return -EINVAL;
1122 	if (start < old_start || last > old_last)
1123 		return -EINVAL;
1124 
1125 	svms = prange->svms;
1126 	if (old_start == start)
1127 		*new = svm_range_new(svms, last + 1, old_last, false);
1128 	else
1129 		*new = svm_range_new(svms, old_start, start - 1, false);
1130 	if (!*new)
1131 		return -ENOMEM;
1132 
1133 	r = svm_range_split_adjust(*new, prange, start, last);
1134 	if (r) {
1135 		pr_debug("failed %d split [0x%llx 0x%llx] to [0x%llx 0x%llx]\n",
1136 			 r, old_start, old_last, start, last);
1137 		svm_range_free(*new, false);
1138 		*new = NULL;
1139 	}
1140 
1141 	return r;
1142 }
1143 
1144 static int
1145 svm_range_split_tail(struct svm_range *prange, uint64_t new_last,
1146 		     struct list_head *insert_list, struct list_head *remap_list)
1147 {
1148 	unsigned long last_align_down = ALIGN_DOWN(prange->last, 512);
1149 	unsigned long start_align = ALIGN(prange->start, 512);
1150 	bool huge_page_mapping = last_align_down > start_align;
1151 	struct svm_range *tail = NULL;
1152 	int r;
1153 
1154 	r = svm_range_split(prange, prange->start, new_last, &tail);
1155 
1156 	if (r)
1157 		return r;
1158 
1159 	list_add(&tail->list, insert_list);
1160 
1161 	if (huge_page_mapping && tail->start > start_align &&
1162 	    tail->start < last_align_down && (!IS_ALIGNED(tail->start, 512)))
1163 		list_add(&tail->update_list, remap_list);
1164 
1165 	return 0;
1166 }
1167 
1168 static int
1169 svm_range_split_head(struct svm_range *prange, uint64_t new_start,
1170 		     struct list_head *insert_list, struct list_head *remap_list)
1171 {
1172 	unsigned long last_align_down = ALIGN_DOWN(prange->last, 512);
1173 	unsigned long start_align = ALIGN(prange->start, 512);
1174 	bool huge_page_mapping = last_align_down > start_align;
1175 	struct svm_range *head = NULL;
1176 	int r;
1177 
1178 	r = svm_range_split(prange, new_start, prange->last, &head);
1179 
1180 	if (r)
1181 		return r;
1182 
1183 	list_add(&head->list, insert_list);
1184 
1185 	if (huge_page_mapping && head->last + 1 > start_align &&
1186 	    head->last + 1 < last_align_down && (!IS_ALIGNED(head->last, 512)))
1187 		list_add(&head->update_list, remap_list);
1188 
1189 	return 0;
1190 }
1191 
1192 static void
1193 svm_range_add_child(struct svm_range *prange, struct svm_range *pchild, enum svm_work_list_ops op)
1194 {
1195 	pr_debug("add child 0x%p [0x%lx 0x%lx] to prange 0x%p child list %d\n",
1196 		 pchild, pchild->start, pchild->last, prange, op);
1197 
1198 	pchild->work_item.mm = NULL;
1199 	pchild->work_item.op = op;
1200 	list_add_tail(&pchild->child_list, &prange->child_list);
1201 }
1202 
1203 static bool
1204 svm_nodes_in_same_hive(struct kfd_node *node_a, struct kfd_node *node_b)
1205 {
1206 	return (node_a->adev == node_b->adev ||
1207 		amdgpu_xgmi_same_hive(node_a->adev, node_b->adev));
1208 }
1209 
1210 static uint64_t
1211 svm_range_get_pte_flags(struct kfd_node *node, struct amdgpu_vm *vm,
1212 			struct svm_range *prange, int domain)
1213 {
1214 	struct kfd_node *bo_node;
1215 	uint32_t flags = prange->flags;
1216 	uint32_t mapping_flags = 0;
1217 	uint32_t gc_ip_version = KFD_GC_VERSION(node);
1218 	uint64_t pte_flags;
1219 	bool snoop = (domain != SVM_RANGE_VRAM_DOMAIN);
1220 	bool coherent = flags & (KFD_IOCTL_SVM_FLAG_COHERENT | KFD_IOCTL_SVM_FLAG_EXT_COHERENT);
1221 	bool ext_coherent = flags & KFD_IOCTL_SVM_FLAG_EXT_COHERENT;
1222 	unsigned int mtype_local;
1223 
1224 	if (domain == SVM_RANGE_VRAM_DOMAIN)
1225 		bo_node = prange->svm_bo->node;
1226 
1227 	switch (gc_ip_version) {
1228 	case IP_VERSION(9, 4, 1):
1229 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1230 			if (bo_node == node) {
1231 				mapping_flags |= coherent ?
1232 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1233 			} else {
1234 				mapping_flags |= coherent ?
1235 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1236 				if (svm_nodes_in_same_hive(node, bo_node))
1237 					snoop = true;
1238 			}
1239 		} else {
1240 			mapping_flags |= coherent ?
1241 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1242 		}
1243 		break;
1244 	case IP_VERSION(9, 4, 2):
1245 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1246 			if (bo_node == node) {
1247 				mapping_flags |= coherent ?
1248 					AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1249 				if (node->adev->gmc.xgmi.connected_to_cpu)
1250 					snoop = true;
1251 			} else {
1252 				mapping_flags |= coherent ?
1253 					AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1254 				if (svm_nodes_in_same_hive(node, bo_node))
1255 					snoop = true;
1256 			}
1257 		} else {
1258 			mapping_flags |= coherent ?
1259 				AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1260 		}
1261 		break;
1262 	case IP_VERSION(9, 4, 3):
1263 	case IP_VERSION(9, 4, 4):
1264 	case IP_VERSION(9, 5, 0):
1265 		if (ext_coherent)
1266 			mtype_local = AMDGPU_VM_MTYPE_CC;
1267 		else
1268 			mtype_local = amdgpu_mtype_local == 1 ? AMDGPU_VM_MTYPE_NC :
1269 				amdgpu_mtype_local == 2 ? AMDGPU_VM_MTYPE_CC : AMDGPU_VM_MTYPE_RW;
1270 		snoop = true;
1271 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1272 			/* local HBM region close to partition */
1273 			if (bo_node->adev == node->adev &&
1274 			    (!bo_node->xcp || !node->xcp || bo_node->xcp->mem_id == node->xcp->mem_id))
1275 				mapping_flags |= mtype_local;
1276 			/* local HBM region far from partition or remote XGMI GPU
1277 			 * with regular system scope coherence
1278 			 */
1279 			else if (svm_nodes_in_same_hive(bo_node, node) && !ext_coherent)
1280 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1281 			/* PCIe P2P on GPUs pre-9.5.0 */
1282 			else if (gc_ip_version < IP_VERSION(9, 5, 0) &&
1283 				 !svm_nodes_in_same_hive(bo_node, node))
1284 				mapping_flags |= AMDGPU_VM_MTYPE_UC;
1285 			/* Other remote memory */
1286 			else
1287 				mapping_flags |= ext_coherent ? AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1288 		/* system memory accessed by the APU */
1289 		} else if (node->adev->flags & AMD_IS_APU) {
1290 			/* On NUMA systems, locality is determined per-page
1291 			 * in amdgpu_gmc_override_vm_pte_flags
1292 			 */
1293 			if (num_possible_nodes() <= 1)
1294 				mapping_flags |= mtype_local;
1295 			else
1296 				mapping_flags |= ext_coherent ? AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1297 		/* system memory accessed by the dGPU */
1298 		} else {
1299 			if (gc_ip_version < IP_VERSION(9, 5, 0) || ext_coherent)
1300 				mapping_flags |= AMDGPU_VM_MTYPE_UC;
1301 			else
1302 				mapping_flags |= AMDGPU_VM_MTYPE_NC;
1303 		}
1304 		break;
1305 	case IP_VERSION(12, 0, 0):
1306 	case IP_VERSION(12, 0, 1):
1307 		mapping_flags |= AMDGPU_VM_MTYPE_NC;
1308 		break;
1309 	case IP_VERSION(12, 1, 0):
1310 		snoop = true;
1311 		if (domain == SVM_RANGE_VRAM_DOMAIN) {
1312 			mtype_local = amdgpu_mtype_local == 1 ? AMDGPU_VM_MTYPE_NC :
1313 								AMDGPU_VM_MTYPE_RW;
1314 			/* local HBM  */
1315 			if (bo_node->adev == node->adev)
1316 				mapping_flags |= mtype_local;
1317 			/* Remote GPU memory */
1318 			else
1319 				mapping_flags |= ext_coherent ? AMDGPU_VM_MTYPE_UC :
1320 								AMDGPU_VM_MTYPE_NC;
1321 		/* system memory accessed by the dGPU */
1322 		} else {
1323 			mapping_flags |= ext_coherent ? AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1324 		}
1325 		break;
1326 	default:
1327 		mapping_flags |= coherent ?
1328 			AMDGPU_VM_MTYPE_UC : AMDGPU_VM_MTYPE_NC;
1329 	}
1330 
1331 	if (flags & KFD_IOCTL_SVM_FLAG_GPU_EXEC)
1332 		mapping_flags |= AMDGPU_VM_PAGE_EXECUTABLE;
1333 
1334 	pte_flags = AMDGPU_PTE_VALID;
1335 	pte_flags |= (domain == SVM_RANGE_VRAM_DOMAIN) ? 0 : AMDGPU_PTE_SYSTEM;
1336 	pte_flags |= snoop ? AMDGPU_PTE_SNOOPED : 0;
1337 	if (gc_ip_version >= IP_VERSION(12, 0, 0))
1338 		pte_flags |= AMDGPU_PTE_IS_PTE;
1339 
1340 	amdgpu_gmc_get_vm_pte(node->adev, vm, NULL, mapping_flags, &pte_flags);
1341 	pte_flags |= AMDGPU_PTE_READABLE;
1342 	if (!(flags & KFD_IOCTL_SVM_FLAG_GPU_RO))
1343 		pte_flags |= AMDGPU_PTE_WRITEABLE;
1344 
1345 	if ((gc_ip_version == IP_VERSION(12, 1, 0)) &&
1346 	    node->adev->have_atomics_support)
1347 		pte_flags |= AMDGPU_PTE_BUS_ATOMICS;
1348 
1349 	return pte_flags;
1350 }
1351 
1352 static int
1353 svm_range_unmap_from_gpu(struct amdgpu_device *adev, struct amdgpu_vm *vm,
1354 			 uint64_t start, uint64_t last,
1355 			 struct dma_fence **fence)
1356 {
1357 	uint64_t init_pte_value = adev->gmc.init_pte_flags;
1358 
1359 	pr_debug("[0x%llx 0x%llx]\n", start, last);
1360 
1361 	return amdgpu_vm_update_range(adev, vm, false, true, true, false, NULL, start,
1362 				      last, init_pte_value, 0, 0, NULL, NULL,
1363 				      fence);
1364 }
1365 
1366 static int
1367 svm_range_unmap_from_gpus(struct svm_range *prange, unsigned long start,
1368 			  unsigned long last, uint32_t trigger)
1369 {
1370 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1371 	struct kfd_process_device *pdd;
1372 	struct dma_fence *fence = NULL;
1373 	struct kfd_process *p;
1374 	uint32_t gpuidx;
1375 	int r = 0;
1376 
1377 	if (!prange->mapped_to_gpu) {
1378 		pr_debug("prange 0x%p [0x%lx 0x%lx] not mapped to GPU\n",
1379 			 prange, prange->start, prange->last);
1380 		return 0;
1381 	}
1382 
1383 	if (prange->start == start && prange->last == last) {
1384 		pr_debug("unmap svms 0x%p prange 0x%p\n", prange->svms, prange);
1385 		prange->mapped_to_gpu = false;
1386 	}
1387 
1388 	bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
1389 		  MAX_GPU_INSTANCE);
1390 	p = container_of(prange->svms, struct kfd_process, svms);
1391 
1392 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1393 		pr_debug("unmap from gpu idx 0x%x\n", gpuidx);
1394 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1395 		if (!pdd) {
1396 			pr_debug("failed to find device idx %d\n", gpuidx);
1397 			return -EINVAL;
1398 		}
1399 
1400 		kfd_smi_event_unmap_from_gpu(pdd->dev, p->lead_thread->pid,
1401 					     start, last, trigger);
1402 
1403 		r = svm_range_unmap_from_gpu(pdd->dev->adev,
1404 					     drm_priv_to_vm(pdd->drm_priv),
1405 					     start, last, &fence);
1406 		if (r)
1407 			break;
1408 
1409 		if (fence) {
1410 			r = dma_fence_wait(fence, false);
1411 			dma_fence_put(fence);
1412 			fence = NULL;
1413 			if (r)
1414 				break;
1415 		}
1416 		kfd_flush_tlb(pdd, TLB_FLUSH_HEAVYWEIGHT);
1417 	}
1418 
1419 	return r;
1420 }
1421 
1422 static int
1423 svm_range_map_to_gpu(struct kfd_process_device *pdd, struct svm_range *prange,
1424 		     unsigned long offset, unsigned long npages, bool readonly,
1425 		     dma_addr_t *dma_addr, struct amdgpu_device *bo_adev,
1426 		     struct dma_fence **fence, bool flush_tlb)
1427 {
1428 	struct amdgpu_device *adev = pdd->dev->adev;
1429 	struct amdgpu_vm *vm = drm_priv_to_vm(pdd->drm_priv);
1430 	uint64_t pte_flags;
1431 	unsigned long last_start;
1432 	int last_domain;
1433 	int r = 0;
1434 	int64_t i, j;
1435 
1436 	last_start = prange->start + offset;
1437 
1438 	pr_debug("svms 0x%p [0x%lx 0x%lx] readonly %d\n", prange->svms,
1439 		 last_start, last_start + npages - 1, readonly);
1440 
1441 	for (i = offset; i < offset + npages; i++) {
1442 		last_domain = dma_addr[i] & SVM_RANGE_VRAM_DOMAIN;
1443 		dma_addr[i] &= ~SVM_RANGE_VRAM_DOMAIN;
1444 
1445 		/* Collect all pages in the same address range and memory domain
1446 		 * that can be mapped with a single call to update mapping.
1447 		 */
1448 		if (i < offset + npages - 1 &&
1449 		    last_domain == (dma_addr[i + 1] & SVM_RANGE_VRAM_DOMAIN))
1450 			continue;
1451 
1452 		pr_debug("Mapping range [0x%lx 0x%llx] on domain: %s\n",
1453 			 last_start, prange->start + i, last_domain ? "GPU" : "CPU");
1454 
1455 		pte_flags = svm_range_get_pte_flags(pdd->dev, vm, prange, last_domain);
1456 		if (readonly)
1457 			pte_flags &= ~AMDGPU_PTE_WRITEABLE;
1458 
1459 		pr_debug("svms 0x%p map [0x%lx 0x%llx] vram %d PTE 0x%llx\n",
1460 			 prange->svms, last_start, prange->start + i,
1461 			 (last_domain == SVM_RANGE_VRAM_DOMAIN) ? 1 : 0,
1462 			 pte_flags);
1463 
1464 		/* For dGPU mode, we use same vm_manager to allocate VRAM for
1465 		 * different memory partition based on fpfn/lpfn, we should use
1466 		 * same vm_manager.vram_base_offset regardless memory partition.
1467 		 */
1468 		r = amdgpu_vm_update_range(adev, vm, false, false, flush_tlb, true,
1469 					   NULL, last_start, prange->start + i,
1470 					   pte_flags,
1471 					   (last_start - prange->start) << PAGE_SHIFT,
1472 					   bo_adev ? bo_adev->vm_manager.vram_base_offset : 0,
1473 					   NULL, dma_addr, &vm->last_update);
1474 
1475 		for (j = last_start - prange->start; j <= i; j++)
1476 			dma_addr[j] |= last_domain;
1477 
1478 		if (r) {
1479 			pr_debug("failed %d to map to gpu 0x%lx\n", r, prange->start);
1480 			goto out;
1481 		}
1482 		last_start = prange->start + i + 1;
1483 	}
1484 
1485 	r = amdgpu_vm_update_pdes(adev, vm, false);
1486 	if (r) {
1487 		pr_debug("failed %d to update directories 0x%lx\n", r,
1488 			 prange->start);
1489 		goto out;
1490 	}
1491 
1492 	if (fence)
1493 		*fence = dma_fence_get(vm->last_update);
1494 
1495 out:
1496 	return r;
1497 }
1498 
1499 static int
1500 svm_range_map_to_gpus(struct svm_range *prange, unsigned long offset,
1501 		      unsigned long npages, bool readonly,
1502 		      unsigned long *bitmap, bool wait, bool flush_tlb)
1503 {
1504 	struct kfd_process_device *pdd;
1505 	struct amdgpu_device *bo_adev = NULL;
1506 	struct kfd_process *p;
1507 	struct dma_fence *fence = NULL;
1508 	uint32_t gpuidx;
1509 	int r = 0;
1510 
1511 	if (prange->svm_bo && prange->ttm_res)
1512 		bo_adev = prange->svm_bo->node->adev;
1513 
1514 	p = container_of(prange->svms, struct kfd_process, svms);
1515 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
1516 		pr_debug("mapping to gpu idx 0x%x\n", gpuidx);
1517 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1518 		if (!pdd) {
1519 			pr_debug("failed to find device idx %d\n", gpuidx);
1520 			return -EINVAL;
1521 		}
1522 
1523 		pdd = kfd_bind_process_to_device(pdd->dev, p);
1524 		if (IS_ERR(pdd))
1525 			return -EINVAL;
1526 
1527 		if (bo_adev && pdd->dev->adev != bo_adev &&
1528 		    !amdgpu_xgmi_same_hive(pdd->dev->adev, bo_adev)) {
1529 			pr_debug("cannot map to device idx %d\n", gpuidx);
1530 			continue;
1531 		}
1532 
1533 		r = svm_range_map_to_gpu(pdd, prange, offset, npages, readonly,
1534 					 prange->dma_addr[gpuidx],
1535 					 bo_adev, wait ? &fence : NULL,
1536 					 flush_tlb);
1537 		if (r)
1538 			break;
1539 
1540 		if (fence) {
1541 			r = dma_fence_wait(fence, false);
1542 			dma_fence_put(fence);
1543 			fence = NULL;
1544 			if (r) {
1545 				pr_debug("failed %d to dma fence wait\n", r);
1546 				break;
1547 			}
1548 		}
1549 
1550 		kfd_flush_tlb(pdd, TLB_FLUSH_LEGACY);
1551 	}
1552 
1553 	return r;
1554 }
1555 
1556 struct svm_validate_context {
1557 	struct kfd_process *process;
1558 	struct svm_range *prange;
1559 	bool intr;
1560 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
1561 	struct drm_exec exec;
1562 };
1563 
1564 static int svm_range_reserve_bos(struct svm_validate_context *ctx, bool intr)
1565 {
1566 	struct kfd_process_device *pdd;
1567 	struct amdgpu_vm *vm;
1568 	uint32_t gpuidx;
1569 	int r;
1570 
1571 	drm_exec_init(&ctx->exec, intr ? DRM_EXEC_INTERRUPTIBLE_WAIT: 0, 0);
1572 	drm_exec_until_all_locked(&ctx->exec) {
1573 		for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1574 			pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1575 			if (!pdd) {
1576 				pr_debug("failed to find device idx %d\n", gpuidx);
1577 				r = -EINVAL;
1578 				goto unreserve_out;
1579 			}
1580 			vm = drm_priv_to_vm(pdd->drm_priv);
1581 
1582 			r = amdgpu_vm_lock_pd(vm, &ctx->exec, 2);
1583 			drm_exec_retry_on_contention(&ctx->exec);
1584 			if (unlikely(r)) {
1585 				pr_debug("failed %d to reserve bo\n", r);
1586 				goto unreserve_out;
1587 			}
1588 		}
1589 	}
1590 
1591 	for_each_set_bit(gpuidx, ctx->bitmap, MAX_GPU_INSTANCE) {
1592 		pdd = kfd_process_device_from_gpuidx(ctx->process, gpuidx);
1593 		if (!pdd) {
1594 			pr_debug("failed to find device idx %d\n", gpuidx);
1595 			r = -EINVAL;
1596 			goto unreserve_out;
1597 		}
1598 
1599 		r = amdgpu_vm_validate(pdd->dev->adev,
1600 				       drm_priv_to_vm(pdd->drm_priv), NULL,
1601 				       svm_range_bo_validate, NULL);
1602 		if (r) {
1603 			pr_debug("failed %d validate pt bos\n", r);
1604 			goto unreserve_out;
1605 		}
1606 	}
1607 
1608 	return 0;
1609 
1610 unreserve_out:
1611 	drm_exec_fini(&ctx->exec);
1612 	return r;
1613 }
1614 
1615 static void svm_range_unreserve_bos(struct svm_validate_context *ctx)
1616 {
1617 	drm_exec_fini(&ctx->exec);
1618 }
1619 
1620 static void *kfd_svm_page_owner(struct kfd_process *p, int32_t gpuidx)
1621 {
1622 	struct kfd_process_device *pdd;
1623 
1624 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
1625 	if (!pdd)
1626 		return NULL;
1627 
1628 	return SVM_ADEV_PGMAP_OWNER(pdd->dev->adev);
1629 }
1630 
1631 /*
1632  * Validation+GPU mapping with concurrent invalidation (MMU notifiers)
1633  *
1634  * To prevent concurrent destruction or change of range attributes, the
1635  * svm_read_lock must be held. The caller must not hold the svm_write_lock
1636  * because that would block concurrent evictions and lead to deadlocks. To
1637  * serialize concurrent migrations or validations of the same range, the
1638  * prange->migrate_mutex must be held.
1639  *
1640  * For VRAM ranges, the SVM BO must be allocated and valid (protected by its
1641  * eviction fence.
1642  *
1643  * The following sequence ensures race-free validation and GPU mapping:
1644  *
1645  * 1. Reserve page table (and SVM BO if range is in VRAM)
1646  * 2. hmm_range_fault to get page addresses (if system memory)
1647  * 3. DMA-map pages (if system memory)
1648  * 4-a. Take notifier lock
1649  * 4-b. Check that pages still valid (mmu_interval_read_retry)
1650  * 4-c. Check that the range was not split or otherwise invalidated
1651  * 4-d. Update GPU page table
1652  * 4.e. Release notifier lock
1653  * 5. Release page table (and SVM BO) reservation
1654  */
1655 static int svm_range_validate_and_map(struct mm_struct *mm,
1656 				      unsigned long map_start, unsigned long map_last,
1657 				      struct svm_range *prange, int32_t gpuidx,
1658 				      bool intr, bool wait, bool flush_tlb)
1659 {
1660 	struct svm_validate_context *ctx;
1661 	unsigned long start, end, addr;
1662 	struct kfd_process *p;
1663 	void *owner;
1664 	int32_t idx;
1665 	int r = 0;
1666 
1667 	ctx = kzalloc(sizeof(struct svm_validate_context), GFP_KERNEL);
1668 	if (!ctx)
1669 		return -ENOMEM;
1670 	ctx->process = container_of(prange->svms, struct kfd_process, svms);
1671 	ctx->prange = prange;
1672 	ctx->intr = intr;
1673 
1674 	if (gpuidx < MAX_GPU_INSTANCE) {
1675 		bitmap_zero(ctx->bitmap, MAX_GPU_INSTANCE);
1676 		bitmap_set(ctx->bitmap, gpuidx, 1);
1677 	} else if (ctx->process->xnack_enabled) {
1678 		bitmap_copy(ctx->bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
1679 
1680 		/* If prefetch range to GPU, or GPU retry fault migrate range to
1681 		 * GPU, which has ACCESS attribute to the range, create mapping
1682 		 * on that GPU.
1683 		 */
1684 		if (prange->actual_loc) {
1685 			gpuidx = kfd_process_gpuidx_from_gpuid(ctx->process,
1686 							prange->actual_loc);
1687 			if (gpuidx < 0) {
1688 				WARN_ONCE(1, "failed get device by id 0x%x\n",
1689 					 prange->actual_loc);
1690 				r = -EINVAL;
1691 				goto free_ctx;
1692 			}
1693 			if (test_bit(gpuidx, prange->bitmap_access))
1694 				bitmap_set(ctx->bitmap, gpuidx, 1);
1695 		}
1696 
1697 		/*
1698 		 * If prange is already mapped or with always mapped flag,
1699 		 * update mapping on GPUs with ACCESS attribute
1700 		 */
1701 		if (bitmap_empty(ctx->bitmap, MAX_GPU_INSTANCE)) {
1702 			if (prange->mapped_to_gpu ||
1703 			    prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)
1704 				bitmap_copy(ctx->bitmap, prange->bitmap_access, MAX_GPU_INSTANCE);
1705 		}
1706 	} else {
1707 		bitmap_or(ctx->bitmap, prange->bitmap_access,
1708 			  prange->bitmap_aip, MAX_GPU_INSTANCE);
1709 	}
1710 
1711 	if (bitmap_empty(ctx->bitmap, MAX_GPU_INSTANCE)) {
1712 		r = 0;
1713 		goto free_ctx;
1714 	}
1715 
1716 	if (prange->actual_loc && !prange->ttm_res) {
1717 		/* This should never happen. actual_loc gets set by
1718 		 * svm_migrate_ram_to_vram after allocating a BO.
1719 		 */
1720 		WARN_ONCE(1, "VRAM BO missing during validation\n");
1721 		r = -EINVAL;
1722 		goto free_ctx;
1723 	}
1724 
1725 	r = svm_range_reserve_bos(ctx, intr);
1726 	if (r)
1727 		goto free_ctx;
1728 
1729 	p = container_of(prange->svms, struct kfd_process, svms);
1730 	owner = kfd_svm_page_owner(p, find_first_bit(ctx->bitmap,
1731 						MAX_GPU_INSTANCE));
1732 	for_each_set_bit(idx, ctx->bitmap, MAX_GPU_INSTANCE) {
1733 		if (kfd_svm_page_owner(p, idx) != owner) {
1734 			owner = NULL;
1735 			break;
1736 		}
1737 	}
1738 
1739 	start = map_start << PAGE_SHIFT;
1740 	end = (map_last + 1) << PAGE_SHIFT;
1741 	for (addr = start; !r && addr < end; ) {
1742 		struct amdgpu_hmm_range *range = NULL;
1743 		unsigned long map_start_vma;
1744 		unsigned long map_last_vma;
1745 		struct vm_area_struct *vma;
1746 		unsigned long next = 0;
1747 		unsigned long offset;
1748 		unsigned long npages;
1749 		bool readonly;
1750 
1751 		vma = vma_lookup(mm, addr);
1752 		if (vma) {
1753 			readonly = !(vma->vm_flags & VM_WRITE);
1754 
1755 			next = min(vma->vm_end, end);
1756 			npages = (next - addr) >> PAGE_SHIFT;
1757 			/* HMM requires at least READ permissions. If provided with PROT_NONE,
1758 			 * unmap the memory. If it's not already mapped, this is a no-op
1759 			 * If PROT_WRITE is provided without READ, warn first then unmap
1760 			 */
1761 			if (!(vma->vm_flags & VM_READ)) {
1762 				unsigned long e, s;
1763 
1764 				svm_range_lock(prange);
1765 				if (vma->vm_flags & VM_WRITE)
1766 					pr_debug("VM_WRITE without VM_READ is not supported");
1767 				s = max(start, prange->start);
1768 				e = min(end, prange->last);
1769 				if (e >= s)
1770 					r = svm_range_unmap_from_gpus(prange, s, e,
1771 						       KFD_SVM_UNMAP_TRIGGER_UNMAP_FROM_CPU);
1772 				svm_range_unlock(prange);
1773 				/* If unmap returns non-zero, we'll bail on the next for loop
1774 				 * iteration, so just leave r and continue
1775 				 */
1776 				addr = next;
1777 				continue;
1778 			}
1779 
1780 			WRITE_ONCE(p->svms.faulting_task, current);
1781 			range = amdgpu_hmm_range_alloc(NULL);
1782 			if (likely(range))
1783 				r = amdgpu_hmm_range_get_pages(&prange->notifier, addr, npages,
1784 							       readonly, owner, range);
1785 			else
1786 				r = -ENOMEM;
1787 			WRITE_ONCE(p->svms.faulting_task, NULL);
1788 			if (r)
1789 				pr_debug("failed %d to get svm range pages\n", r);
1790 		} else {
1791 			r = -EFAULT;
1792 		}
1793 
1794 		if (!r) {
1795 			offset = (addr >> PAGE_SHIFT) - prange->start;
1796 			r = svm_range_dma_map(prange, ctx->bitmap, offset, npages,
1797 					      range->hmm_range.hmm_pfns);
1798 			if (r)
1799 				pr_debug("failed %d to dma map range\n", r);
1800 		}
1801 
1802 		svm_range_lock(prange);
1803 
1804 		/* Free backing memory of hmm_range if it was initialized
1805 		 * Override return value to TRY AGAIN only if prior returns
1806 		 * were successful
1807 		 */
1808 		if (range && !amdgpu_hmm_range_valid(range) && !r) {
1809 			pr_debug("hmm update the range, need validate again\n");
1810 			r = -EAGAIN;
1811 		}
1812 
1813 		/* Free the hmm range */
1814 		amdgpu_hmm_range_free(range);
1815 
1816 		if (!r && !list_empty(&prange->child_list)) {
1817 			pr_debug("range split by unmap in parallel, validate again\n");
1818 			r = -EAGAIN;
1819 		}
1820 
1821 		if (!r) {
1822 			map_start_vma = max(map_start, prange->start + offset);
1823 			map_last_vma = min(map_last, prange->start + offset + npages - 1);
1824 			if (map_start_vma <= map_last_vma) {
1825 				offset = map_start_vma - prange->start;
1826 				npages = map_last_vma - map_start_vma + 1;
1827 				r = svm_range_map_to_gpus(prange, offset, npages, readonly,
1828 							  ctx->bitmap, wait, flush_tlb);
1829 			}
1830 		}
1831 
1832 		if (!r && next == end)
1833 			prange->mapped_to_gpu = true;
1834 
1835 		svm_range_unlock(prange);
1836 
1837 		addr = next;
1838 	}
1839 
1840 	svm_range_unreserve_bos(ctx);
1841 	if (!r)
1842 		prange->validate_timestamp = ktime_get_boottime();
1843 
1844 free_ctx:
1845 	kfree(ctx);
1846 
1847 	return r;
1848 }
1849 
1850 /**
1851  * svm_range_list_lock_and_flush_work - flush pending deferred work
1852  *
1853  * @svms: the svm range list
1854  * @mm: the mm structure
1855  *
1856  * Context: Returns with mmap write lock held, pending deferred work flushed
1857  *
1858  */
1859 void
1860 svm_range_list_lock_and_flush_work(struct svm_range_list *svms,
1861 				   struct mm_struct *mm)
1862 {
1863 retry_flush_work:
1864 	flush_work(&svms->deferred_list_work);
1865 	mmap_write_lock(mm);
1866 
1867 	if (list_empty(&svms->deferred_range_list))
1868 		return;
1869 	mmap_write_unlock(mm);
1870 	pr_debug("retry flush\n");
1871 	goto retry_flush_work;
1872 }
1873 
1874 static void svm_range_restore_work(struct work_struct *work)
1875 {
1876 	struct delayed_work *dwork = to_delayed_work(work);
1877 	struct amdkfd_process_info *process_info;
1878 	struct svm_range_list *svms;
1879 	struct svm_range *prange;
1880 	struct kfd_process *p;
1881 	struct mm_struct *mm;
1882 	int evicted_ranges;
1883 	int invalid;
1884 	int r;
1885 
1886 	svms = container_of(dwork, struct svm_range_list, restore_work);
1887 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1888 	if (!evicted_ranges)
1889 		return;
1890 
1891 	pr_debug("restore svm ranges\n");
1892 
1893 	p = container_of(svms, struct kfd_process, svms);
1894 	process_info = p->kgd_process_info;
1895 
1896 	/* Keep mm reference when svm_range_validate_and_map ranges */
1897 	mm = get_task_mm(p->lead_thread);
1898 	if (!mm) {
1899 		pr_debug("svms 0x%p process mm gone\n", svms);
1900 		return;
1901 	}
1902 
1903 	mutex_lock(&process_info->lock);
1904 	svm_range_list_lock_and_flush_work(svms, mm);
1905 	mutex_lock(&svms->lock);
1906 
1907 	evicted_ranges = atomic_read(&svms->evicted_ranges);
1908 
1909 	list_for_each_entry(prange, &svms->list, list) {
1910 		invalid = atomic_read(&prange->invalid);
1911 		if (!invalid)
1912 			continue;
1913 
1914 		pr_debug("restoring svms 0x%p prange 0x%p [0x%lx %lx] inv %d\n",
1915 			 prange->svms, prange, prange->start, prange->last,
1916 			 invalid);
1917 
1918 		/*
1919 		 * If range is migrating, wait for migration is done.
1920 		 */
1921 		mutex_lock(&prange->migrate_mutex);
1922 
1923 		r = svm_range_validate_and_map(mm, prange->start, prange->last, prange,
1924 					       MAX_GPU_INSTANCE, false, true, false);
1925 		if (r)
1926 			pr_debug("failed %d to map 0x%lx to gpus\n", r,
1927 				 prange->start);
1928 
1929 		mutex_unlock(&prange->migrate_mutex);
1930 		if (r)
1931 			goto out_reschedule;
1932 
1933 		if (atomic_cmpxchg(&prange->invalid, invalid, 0) != invalid)
1934 			goto out_reschedule;
1935 	}
1936 
1937 	if (atomic_cmpxchg(&svms->evicted_ranges, evicted_ranges, 0) !=
1938 	    evicted_ranges)
1939 		goto out_reschedule;
1940 
1941 	evicted_ranges = 0;
1942 
1943 	r = kgd2kfd_resume_mm(mm);
1944 	if (r) {
1945 		/* No recovery from this failure. Probably the CP is
1946 		 * hanging. No point trying again.
1947 		 */
1948 		pr_debug("failed %d to resume KFD\n", r);
1949 	}
1950 
1951 	pr_debug("restore svm ranges successfully\n");
1952 
1953 out_reschedule:
1954 	mutex_unlock(&svms->lock);
1955 	mmap_write_unlock(mm);
1956 	mutex_unlock(&process_info->lock);
1957 
1958 	/* If validation failed, reschedule another attempt */
1959 	if (evicted_ranges) {
1960 		pr_debug("reschedule to restore svm range\n");
1961 		queue_delayed_work(system_freezable_wq, &svms->restore_work,
1962 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
1963 
1964 		kfd_smi_event_queue_restore_rescheduled(mm);
1965 	}
1966 	mmput(mm);
1967 }
1968 
1969 /**
1970  * svm_range_evict - evict svm range
1971  * @prange: svm range structure
1972  * @mm: current process mm_struct
1973  * @start: starting process queue number
1974  * @last: last process queue number
1975  * @event: mmu notifier event when range is evicted or migrated
1976  *
1977  * Stop all queues of the process to ensure GPU doesn't access the memory, then
1978  * return to let CPU evict the buffer and proceed CPU pagetable update.
1979  *
1980  * Don't need use lock to sync cpu pagetable invalidation with GPU execution.
1981  * If invalidation happens while restore work is running, restore work will
1982  * restart to ensure to get the latest CPU pages mapping to GPU, then start
1983  * the queues.
1984  */
1985 static int
1986 svm_range_evict(struct svm_range *prange, struct mm_struct *mm,
1987 		unsigned long start, unsigned long last,
1988 		enum mmu_notifier_event event)
1989 {
1990 	struct svm_range_list *svms = prange->svms;
1991 	struct svm_range *pchild;
1992 	struct kfd_process *p;
1993 	int r = 0;
1994 
1995 	p = container_of(svms, struct kfd_process, svms);
1996 
1997 	pr_debug("invalidate svms 0x%p prange [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
1998 		 svms, prange->start, prange->last, start, last);
1999 
2000 	if (!p->xnack_enabled ||
2001 	    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) {
2002 		int evicted_ranges;
2003 		bool mapped = prange->mapped_to_gpu;
2004 
2005 		list_for_each_entry(pchild, &prange->child_list, child_list) {
2006 			if (!pchild->mapped_to_gpu)
2007 				continue;
2008 			mapped = true;
2009 			mutex_lock_nested(&pchild->lock, 1);
2010 			if (pchild->start <= last && pchild->last >= start) {
2011 				pr_debug("increment pchild invalid [0x%lx 0x%lx]\n",
2012 					 pchild->start, pchild->last);
2013 				atomic_inc(&pchild->invalid);
2014 			}
2015 			mutex_unlock(&pchild->lock);
2016 		}
2017 
2018 		if (!mapped)
2019 			return r;
2020 
2021 		if (prange->start <= last && prange->last >= start)
2022 			atomic_inc(&prange->invalid);
2023 
2024 		evicted_ranges = atomic_inc_return(&svms->evicted_ranges);
2025 		if (evicted_ranges != 1)
2026 			return r;
2027 
2028 		pr_debug("evicting svms 0x%p range [0x%lx 0x%lx]\n",
2029 			 prange->svms, prange->start, prange->last);
2030 
2031 		/* First eviction, stop the queues */
2032 		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_SVM);
2033 		if (r)
2034 			pr_debug("failed to quiesce KFD\n");
2035 
2036 		pr_debug("schedule to restore svm %p ranges\n", svms);
2037 		queue_delayed_work(system_freezable_wq, &svms->restore_work,
2038 			msecs_to_jiffies(AMDGPU_SVM_RANGE_RESTORE_DELAY_MS));
2039 	} else {
2040 		unsigned long s, l;
2041 		uint32_t trigger;
2042 
2043 		if (event == MMU_NOTIFY_MIGRATE)
2044 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY_MIGRATE;
2045 		else
2046 			trigger = KFD_SVM_UNMAP_TRIGGER_MMU_NOTIFY;
2047 
2048 		pr_debug("invalidate unmap svms 0x%p [0x%lx 0x%lx] from GPUs\n",
2049 			 prange->svms, start, last);
2050 		list_for_each_entry(pchild, &prange->child_list, child_list) {
2051 			mutex_lock_nested(&pchild->lock, 1);
2052 			s = max(start, pchild->start);
2053 			l = min(last, pchild->last);
2054 			if (l >= s)
2055 				svm_range_unmap_from_gpus(pchild, s, l, trigger);
2056 			mutex_unlock(&pchild->lock);
2057 		}
2058 		s = max(start, prange->start);
2059 		l = min(last, prange->last);
2060 		if (l >= s)
2061 			svm_range_unmap_from_gpus(prange, s, l, trigger);
2062 	}
2063 
2064 	return r;
2065 }
2066 
2067 static struct svm_range *svm_range_clone(struct svm_range *old)
2068 {
2069 	struct svm_range *new;
2070 
2071 	new = svm_range_new(old->svms, old->start, old->last, false);
2072 	if (!new)
2073 		return NULL;
2074 	if (svm_range_copy_dma_addrs(new, old)) {
2075 		svm_range_free(new, false);
2076 		return NULL;
2077 	}
2078 	if (old->svm_bo) {
2079 		new->ttm_res = old->ttm_res;
2080 		new->offset = old->offset;
2081 		new->svm_bo = svm_range_bo_ref(old->svm_bo);
2082 		spin_lock(&new->svm_bo->list_lock);
2083 		list_add(&new->svm_bo_list, &new->svm_bo->range_list);
2084 		spin_unlock(&new->svm_bo->list_lock);
2085 	}
2086 	new->flags = old->flags;
2087 	new->preferred_loc = old->preferred_loc;
2088 	new->prefetch_loc = old->prefetch_loc;
2089 	new->actual_loc = old->actual_loc;
2090 	new->granularity = old->granularity;
2091 	new->mapped_to_gpu = old->mapped_to_gpu;
2092 	new->vram_pages = old->vram_pages;
2093 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
2094 	bitmap_copy(new->bitmap_aip, old->bitmap_aip, MAX_GPU_INSTANCE);
2095 	atomic_set(&new->queue_refcount, atomic_read(&old->queue_refcount));
2096 
2097 	return new;
2098 }
2099 
2100 void svm_range_set_max_pages(struct amdgpu_device *adev)
2101 {
2102 	uint64_t max_pages;
2103 	uint64_t pages, _pages;
2104 	uint64_t min_pages = 0;
2105 	int i, id;
2106 
2107 	for (i = 0; i < adev->kfd.dev->num_nodes; i++) {
2108 		if (adev->kfd.dev->nodes[i]->xcp)
2109 			id = adev->kfd.dev->nodes[i]->xcp->id;
2110 		else
2111 			id = -1;
2112 		pages = KFD_XCP_MEMORY_SIZE(adev, id) >> 17;
2113 		pages = clamp(pages, 1ULL << 9, 1ULL << 18);
2114 		pages = rounddown_pow_of_two(pages);
2115 		min_pages = min_not_zero(min_pages, pages);
2116 	}
2117 
2118 	do {
2119 		max_pages = READ_ONCE(max_svm_range_pages);
2120 		_pages = min_not_zero(max_pages, min_pages);
2121 	} while (cmpxchg(&max_svm_range_pages, max_pages, _pages) != max_pages);
2122 }
2123 
2124 static int
2125 svm_range_split_new(struct svm_range_list *svms, uint64_t start, uint64_t last,
2126 		    uint64_t max_pages, struct list_head *insert_list,
2127 		    struct list_head *update_list)
2128 {
2129 	struct svm_range *prange;
2130 	uint64_t l;
2131 
2132 	pr_debug("max_svm_range_pages 0x%llx adding [0x%llx 0x%llx]\n",
2133 		 max_pages, start, last);
2134 
2135 	while (last >= start) {
2136 		l = min(last, ALIGN_DOWN(start + max_pages, max_pages) - 1);
2137 
2138 		prange = svm_range_new(svms, start, l, true);
2139 		if (!prange)
2140 			return -ENOMEM;
2141 		list_add(&prange->list, insert_list);
2142 		list_add(&prange->update_list, update_list);
2143 
2144 		start = l + 1;
2145 	}
2146 	return 0;
2147 }
2148 
2149 /**
2150  * svm_range_add - add svm range and handle overlap
2151  * @p: the range add to this process svms
2152  * @start: page size aligned
2153  * @size: page size aligned
2154  * @nattr: number of attributes
2155  * @attrs: array of attributes
2156  * @update_list: output, the ranges need validate and update GPU mapping
2157  * @insert_list: output, the ranges need insert to svms
2158  * @remove_list: output, the ranges are replaced and need remove from svms
2159  * @remap_list: output, remap unaligned svm ranges
2160  *
2161  * Check if the virtual address range has overlap with any existing ranges,
2162  * split partly overlapping ranges and add new ranges in the gaps. All changes
2163  * should be applied to the range_list and interval tree transactionally. If
2164  * any range split or allocation fails, the entire update fails. Therefore any
2165  * existing overlapping svm_ranges are cloned and the original svm_ranges left
2166  * unchanged.
2167  *
2168  * If the transaction succeeds, the caller can update and insert clones and
2169  * new ranges, then free the originals.
2170  *
2171  * Otherwise the caller can free the clones and new ranges, while the old
2172  * svm_ranges remain unchanged.
2173  *
2174  * Context: Process context, caller must hold svms->lock
2175  *
2176  * Return:
2177  * 0 - OK, otherwise error code
2178  */
2179 static int
2180 svm_range_add(struct kfd_process *p, uint64_t start, uint64_t size,
2181 	      uint32_t nattr, struct kfd_ioctl_svm_attribute *attrs,
2182 	      struct list_head *update_list, struct list_head *insert_list,
2183 	      struct list_head *remove_list, struct list_head *remap_list)
2184 {
2185 	unsigned long last = start + size - 1UL;
2186 	struct svm_range_list *svms = &p->svms;
2187 	struct interval_tree_node *node;
2188 	struct svm_range *prange;
2189 	struct svm_range *tmp;
2190 	struct list_head new_list;
2191 	int r = 0;
2192 
2193 	pr_debug("svms 0x%p [0x%llx 0x%lx]\n", &p->svms, start, last);
2194 
2195 	INIT_LIST_HEAD(update_list);
2196 	INIT_LIST_HEAD(insert_list);
2197 	INIT_LIST_HEAD(remove_list);
2198 	INIT_LIST_HEAD(&new_list);
2199 	INIT_LIST_HEAD(remap_list);
2200 
2201 	node = interval_tree_iter_first(&svms->objects, start, last);
2202 	while (node) {
2203 		struct interval_tree_node *next;
2204 		unsigned long next_start;
2205 
2206 		pr_debug("found overlap node [0x%lx 0x%lx]\n", node->start,
2207 			 node->last);
2208 
2209 		prange = container_of(node, struct svm_range, it_node);
2210 		next = interval_tree_iter_next(node, start, last);
2211 		next_start = min(node->last, last) + 1;
2212 
2213 		if (svm_range_is_same_attrs(p, prange, nattr, attrs) &&
2214 		    prange->mapped_to_gpu) {
2215 			/* nothing to do */
2216 		} else if (node->start < start || node->last > last) {
2217 			/* node intersects the update range and its attributes
2218 			 * will change. Clone and split it, apply updates only
2219 			 * to the overlapping part
2220 			 */
2221 			struct svm_range *old = prange;
2222 
2223 			prange = svm_range_clone(old);
2224 			if (!prange) {
2225 				r = -ENOMEM;
2226 				goto out;
2227 			}
2228 
2229 			list_add(&old->update_list, remove_list);
2230 			list_add(&prange->list, insert_list);
2231 			list_add(&prange->update_list, update_list);
2232 
2233 			if (node->start < start) {
2234 				pr_debug("change old range start\n");
2235 				r = svm_range_split_head(prange, start,
2236 							 insert_list, remap_list);
2237 				if (r)
2238 					goto out;
2239 			}
2240 			if (node->last > last) {
2241 				pr_debug("change old range last\n");
2242 				r = svm_range_split_tail(prange, last,
2243 							 insert_list, remap_list);
2244 				if (r)
2245 					goto out;
2246 			}
2247 		} else {
2248 			/* The node is contained within start..last,
2249 			 * just update it
2250 			 */
2251 			list_add(&prange->update_list, update_list);
2252 		}
2253 
2254 		/* insert a new node if needed */
2255 		if (node->start > start) {
2256 			r = svm_range_split_new(svms, start, node->start - 1,
2257 						READ_ONCE(max_svm_range_pages),
2258 						&new_list, update_list);
2259 			if (r)
2260 				goto out;
2261 		}
2262 
2263 		node = next;
2264 		start = next_start;
2265 	}
2266 
2267 	/* add a final range at the end if needed */
2268 	if (start <= last)
2269 		r = svm_range_split_new(svms, start, last,
2270 					READ_ONCE(max_svm_range_pages),
2271 					&new_list, update_list);
2272 
2273 out:
2274 	if (r) {
2275 		list_for_each_entry_safe(prange, tmp, insert_list, list)
2276 			svm_range_free(prange, false);
2277 		list_for_each_entry_safe(prange, tmp, &new_list, list)
2278 			svm_range_free(prange, true);
2279 	} else {
2280 		list_splice(&new_list, insert_list);
2281 	}
2282 
2283 	return r;
2284 }
2285 
2286 static void
2287 svm_range_update_notifier_and_interval_tree(struct mm_struct *mm,
2288 					    struct svm_range *prange)
2289 {
2290 	unsigned long start;
2291 	unsigned long last;
2292 
2293 	start = prange->notifier.interval_tree.start >> PAGE_SHIFT;
2294 	last = prange->notifier.interval_tree.last >> PAGE_SHIFT;
2295 
2296 	if (prange->start == start && prange->last == last)
2297 		return;
2298 
2299 	pr_debug("up notifier 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n",
2300 		  prange->svms, prange, start, last, prange->start,
2301 		  prange->last);
2302 
2303 	if (start != 0 && last != 0) {
2304 		interval_tree_remove(&prange->it_node, &prange->svms->objects);
2305 		svm_range_remove_notifier(prange);
2306 	}
2307 	prange->it_node.start = prange->start;
2308 	prange->it_node.last = prange->last;
2309 
2310 	interval_tree_insert(&prange->it_node, &prange->svms->objects);
2311 	svm_range_add_notifier_locked(mm, prange);
2312 }
2313 
2314 static void
2315 svm_range_handle_list_op(struct svm_range_list *svms, struct svm_range *prange,
2316 			 struct mm_struct *mm)
2317 {
2318 	switch (prange->work_item.op) {
2319 	case SVM_OP_NULL:
2320 		pr_debug("NULL OP 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2321 			 svms, prange, prange->start, prange->last);
2322 		break;
2323 	case SVM_OP_UNMAP_RANGE:
2324 		pr_debug("remove 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2325 			 svms, prange, prange->start, prange->last);
2326 		svm_range_unlink(prange);
2327 		svm_range_remove_notifier(prange);
2328 		svm_range_free(prange, true);
2329 		break;
2330 	case SVM_OP_UPDATE_RANGE_NOTIFIER:
2331 		pr_debug("update notifier 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2332 			 svms, prange, prange->start, prange->last);
2333 		svm_range_update_notifier_and_interval_tree(mm, prange);
2334 		break;
2335 	case SVM_OP_UPDATE_RANGE_NOTIFIER_AND_MAP:
2336 		pr_debug("update and map 0x%p prange 0x%p [0x%lx 0x%lx]\n",
2337 			 svms, prange, prange->start, prange->last);
2338 		svm_range_update_notifier_and_interval_tree(mm, prange);
2339 		/* TODO: implement deferred validation and mapping */
2340 		break;
2341 	case SVM_OP_ADD_RANGE:
2342 		pr_debug("add 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms, prange,
2343 			 prange->start, prange->last);
2344 		svm_range_add_to_svms(prange);
2345 		svm_range_add_notifier_locked(mm, prange);
2346 		break;
2347 	case SVM_OP_ADD_RANGE_AND_MAP:
2348 		pr_debug("add and map 0x%p prange 0x%p [0x%lx 0x%lx]\n", svms,
2349 			 prange, prange->start, prange->last);
2350 		svm_range_add_to_svms(prange);
2351 		svm_range_add_notifier_locked(mm, prange);
2352 		/* TODO: implement deferred validation and mapping */
2353 		break;
2354 	default:
2355 		WARN_ONCE(1, "Unknown prange 0x%p work op %d\n", prange,
2356 			 prange->work_item.op);
2357 	}
2358 }
2359 
2360 static void svm_range_drain_retry_fault(struct svm_range_list *svms)
2361 {
2362 	struct kfd_process_device *pdd;
2363 	struct kfd_process *p;
2364 	uint32_t i;
2365 
2366 	p = container_of(svms, struct kfd_process, svms);
2367 
2368 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2369 		pdd = p->pdds[i];
2370 		if (!pdd)
2371 			continue;
2372 
2373 		pr_debug("drain retry fault gpu %d svms %p\n", i, svms);
2374 
2375 		if (!down_read_trylock(&pdd->dev->adev->reset_domain->sem))
2376 			continue;
2377 
2378 		amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2379 				pdd->dev->adev->irq.retry_cam_enabled ?
2380 				&pdd->dev->adev->irq.ih :
2381 				&pdd->dev->adev->irq.ih1);
2382 
2383 		if (pdd->dev->adev->irq.retry_cam_enabled)
2384 			amdgpu_ih_wait_on_checkpoint_process_ts(pdd->dev->adev,
2385 				&pdd->dev->adev->irq.ih_soft);
2386 
2387 		up_read(&pdd->dev->adev->reset_domain->sem);
2388 
2389 		pr_debug("drain retry fault gpu %d svms 0x%p done\n", i, svms);
2390 	}
2391 }
2392 
2393 static void svm_range_deferred_list_work(struct work_struct *work)
2394 {
2395 	struct svm_range_list *svms;
2396 	struct svm_range *prange;
2397 	struct mm_struct *mm;
2398 
2399 	svms = container_of(work, struct svm_range_list, deferred_list_work);
2400 	pr_debug("enter svms 0x%p\n", svms);
2401 
2402 	spin_lock(&svms->deferred_list_lock);
2403 	while (!list_empty(&svms->deferred_range_list)) {
2404 		prange = list_first_entry(&svms->deferred_range_list,
2405 					  struct svm_range, deferred_list);
2406 		spin_unlock(&svms->deferred_list_lock);
2407 
2408 		pr_debug("prange 0x%p [0x%lx 0x%lx] op %d\n", prange,
2409 			 prange->start, prange->last, prange->work_item.op);
2410 
2411 		mm = prange->work_item.mm;
2412 
2413 		mmap_write_lock(mm);
2414 
2415 		/* Remove from deferred_list must be inside mmap write lock, for
2416 		 * two race cases:
2417 		 * 1. unmap_from_cpu may change work_item.op and add the range
2418 		 *    to deferred_list again, cause use after free bug.
2419 		 * 2. svm_range_list_lock_and_flush_work may hold mmap write
2420 		 *    lock and continue because deferred_list is empty, but
2421 		 *    deferred_list work is actually waiting for mmap lock.
2422 		 */
2423 		spin_lock(&svms->deferred_list_lock);
2424 		list_del_init(&prange->deferred_list);
2425 		spin_unlock(&svms->deferred_list_lock);
2426 
2427 		mutex_lock(&svms->lock);
2428 		mutex_lock(&prange->migrate_mutex);
2429 		while (!list_empty(&prange->child_list)) {
2430 			struct svm_range *pchild;
2431 
2432 			pchild = list_first_entry(&prange->child_list,
2433 						struct svm_range, child_list);
2434 			pr_debug("child prange 0x%p op %d\n", pchild,
2435 				 pchild->work_item.op);
2436 			list_del_init(&pchild->child_list);
2437 			svm_range_handle_list_op(svms, pchild, mm);
2438 		}
2439 		mutex_unlock(&prange->migrate_mutex);
2440 
2441 		svm_range_handle_list_op(svms, prange, mm);
2442 		mutex_unlock(&svms->lock);
2443 		mmap_write_unlock(mm);
2444 
2445 		/* Pairs with mmget in svm_range_add_list_work. If dropping the
2446 		 * last mm refcount, schedule release work to avoid circular locking
2447 		 */
2448 		mmput_async(mm);
2449 
2450 		spin_lock(&svms->deferred_list_lock);
2451 	}
2452 	spin_unlock(&svms->deferred_list_lock);
2453 	pr_debug("exit svms 0x%p\n", svms);
2454 }
2455 
2456 void
2457 svm_range_add_list_work(struct svm_range_list *svms, struct svm_range *prange,
2458 			struct mm_struct *mm, enum svm_work_list_ops op)
2459 {
2460 	spin_lock(&svms->deferred_list_lock);
2461 	/* if prange is on the deferred list */
2462 	if (!list_empty(&prange->deferred_list)) {
2463 		pr_debug("update exist prange 0x%p work op %d\n", prange, op);
2464 		WARN_ONCE(prange->work_item.mm != mm, "unmatch mm\n");
2465 		if (op != SVM_OP_NULL &&
2466 		    prange->work_item.op != SVM_OP_UNMAP_RANGE)
2467 			prange->work_item.op = op;
2468 	} else {
2469 		/* Pairs with mmput in deferred_list_work.
2470 		 * If process is exiting and mm is gone, don't update mmu notifier.
2471 		 */
2472 		if (mmget_not_zero(mm)) {
2473 			prange->work_item.mm = mm;
2474 			prange->work_item.op = op;
2475 			list_add_tail(&prange->deferred_list,
2476 				      &prange->svms->deferred_range_list);
2477 			pr_debug("add prange 0x%p [0x%lx 0x%lx] to work list op %d\n",
2478 				 prange, prange->start, prange->last, op);
2479 		}
2480 	}
2481 	spin_unlock(&svms->deferred_list_lock);
2482 }
2483 
2484 void schedule_deferred_list_work(struct svm_range_list *svms)
2485 {
2486 	spin_lock(&svms->deferred_list_lock);
2487 	if (!list_empty(&svms->deferred_range_list))
2488 		schedule_work(&svms->deferred_list_work);
2489 	spin_unlock(&svms->deferred_list_lock);
2490 }
2491 
2492 static void
2493 svm_range_unmap_split(struct svm_range *parent, struct svm_range *prange, unsigned long start,
2494 		      unsigned long last)
2495 {
2496 	struct svm_range *head;
2497 	struct svm_range *tail;
2498 
2499 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2500 		pr_debug("prange 0x%p [0x%lx 0x%lx] is already freed\n", prange,
2501 			 prange->start, prange->last);
2502 		return;
2503 	}
2504 	if (start > prange->last || last < prange->start)
2505 		return;
2506 
2507 	head = tail = prange;
2508 	if (start > prange->start)
2509 		svm_range_split(prange, prange->start, start - 1, &tail);
2510 	if (last < tail->last)
2511 		svm_range_split(tail, last + 1, tail->last, &head);
2512 
2513 	if (head != prange && tail != prange) {
2514 		svm_range_add_child(parent, head, SVM_OP_UNMAP_RANGE);
2515 		svm_range_add_child(parent, tail, SVM_OP_ADD_RANGE);
2516 	} else if (tail != prange) {
2517 		svm_range_add_child(parent, tail, SVM_OP_UNMAP_RANGE);
2518 	} else if (head != prange) {
2519 		svm_range_add_child(parent, head, SVM_OP_UNMAP_RANGE);
2520 	} else if (parent != prange) {
2521 		prange->work_item.op = SVM_OP_UNMAP_RANGE;
2522 	}
2523 }
2524 
2525 static void
2526 svm_range_unmap_from_cpu(struct mm_struct *mm, struct svm_range *prange,
2527 			 unsigned long start, unsigned long last)
2528 {
2529 	uint32_t trigger = KFD_SVM_UNMAP_TRIGGER_UNMAP_FROM_CPU;
2530 	struct svm_range_list *svms;
2531 	struct svm_range *pchild;
2532 	struct kfd_process *p;
2533 	unsigned long s, l;
2534 	bool unmap_parent;
2535 	uint32_t i;
2536 
2537 	if (atomic_read(&prange->queue_refcount)) {
2538 		int r;
2539 
2540 		pr_warn("Freeing queue vital buffer 0x%lx, queue evicted\n",
2541 			prange->start << PAGE_SHIFT);
2542 		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_SVM);
2543 		if (r)
2544 			pr_debug("failed %d to quiesce KFD queues\n", r);
2545 	}
2546 
2547 	p = kfd_lookup_process_by_mm(mm);
2548 	if (!p)
2549 		return;
2550 	svms = &p->svms;
2551 
2552 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] [0x%lx 0x%lx]\n", svms,
2553 		 prange, prange->start, prange->last, start, last);
2554 
2555 	/* calculate time stamps that are used to decide which page faults need be
2556 	 * dropped or handled before unmap pages from gpu vm
2557 	 */
2558 	for_each_set_bit(i, svms->bitmap_supported, p->n_pdds) {
2559 		struct kfd_process_device *pdd;
2560 		struct amdgpu_device *adev;
2561 		struct amdgpu_ih_ring *ih;
2562 		uint32_t checkpoint_wptr;
2563 
2564 		pdd = p->pdds[i];
2565 		if (!pdd)
2566 			continue;
2567 
2568 		adev = pdd->dev->adev;
2569 
2570 		/* Check and drain ih1 ring if cam not available */
2571 		if (!adev->irq.retry_cam_enabled && adev->irq.ih1.ring_size) {
2572 			ih = &adev->irq.ih1;
2573 			checkpoint_wptr = amdgpu_ih_get_wptr(adev, ih);
2574 			if (ih->rptr != checkpoint_wptr) {
2575 				svms->checkpoint_ts[i] =
2576 					amdgpu_ih_decode_iv_ts(adev, ih, checkpoint_wptr, -1);
2577 				continue;
2578 			}
2579 		}
2580 
2581 		/* check if dev->irq.ih_soft is not empty */
2582 		ih = &adev->irq.ih_soft;
2583 		checkpoint_wptr = amdgpu_ih_get_wptr(adev, ih);
2584 		if (ih->rptr != checkpoint_wptr)
2585 			svms->checkpoint_ts[i] = amdgpu_ih_decode_iv_ts(adev, ih, checkpoint_wptr, -1);
2586 	}
2587 
2588 	unmap_parent = start <= prange->start && last >= prange->last;
2589 
2590 	list_for_each_entry(pchild, &prange->child_list, child_list) {
2591 		mutex_lock_nested(&pchild->lock, 1);
2592 		s = max(start, pchild->start);
2593 		l = min(last, pchild->last);
2594 		if (l >= s)
2595 			svm_range_unmap_from_gpus(pchild, s, l, trigger);
2596 		svm_range_unmap_split(prange, pchild, start, last);
2597 		mutex_unlock(&pchild->lock);
2598 	}
2599 	s = max(start, prange->start);
2600 	l = min(last, prange->last);
2601 	if (l >= s)
2602 		svm_range_unmap_from_gpus(prange, s, l, trigger);
2603 	svm_range_unmap_split(prange, prange, start, last);
2604 
2605 	if (unmap_parent)
2606 		svm_range_add_list_work(svms, prange, mm, SVM_OP_UNMAP_RANGE);
2607 	else
2608 		svm_range_add_list_work(svms, prange, mm,
2609 					SVM_OP_UPDATE_RANGE_NOTIFIER);
2610 	schedule_deferred_list_work(svms);
2611 
2612 	kfd_unref_process(p);
2613 }
2614 
2615 /**
2616  * svm_range_cpu_invalidate_pagetables - interval notifier callback
2617  * @mni: mmu_interval_notifier struct
2618  * @range: mmu_notifier_range struct
2619  * @cur_seq: value to pass to mmu_interval_set_seq()
2620  *
2621  * If event is MMU_NOTIFY_UNMAP, this is from CPU unmap range, otherwise, it
2622  * is from migration, or CPU page invalidation callback.
2623  *
2624  * For unmap event, unmap range from GPUs, remove prange from svms in a delayed
2625  * work thread, and split prange if only part of prange is unmapped.
2626  *
2627  * For invalidation event, if GPU retry fault is not enabled, evict the queues,
2628  * then schedule svm_range_restore_work to update GPU mapping and resume queues.
2629  * If GPU retry fault is enabled, unmap the svm range from GPU, retry fault will
2630  * update GPU mapping to recover.
2631  *
2632  * Context: mmap lock, notifier_invalidate_start lock are held
2633  *          for invalidate event, prange lock is held if this is from migration
2634  */
2635 static bool
2636 svm_range_cpu_invalidate_pagetables(struct mmu_interval_notifier *mni,
2637 				    const struct mmu_notifier_range *range,
2638 				    unsigned long cur_seq)
2639 {
2640 	struct svm_range *prange;
2641 	unsigned long start;
2642 	unsigned long last;
2643 
2644 	if (range->event == MMU_NOTIFY_RELEASE)
2645 		return true;
2646 
2647 	start = mni->interval_tree.start;
2648 	last = mni->interval_tree.last;
2649 	start = max(start, range->start) >> PAGE_SHIFT;
2650 	last = min(last, range->end - 1) >> PAGE_SHIFT;
2651 	pr_debug("[0x%lx 0x%lx] range[0x%lx 0x%lx] notifier[0x%lx 0x%lx] %d\n",
2652 		 start, last, range->start >> PAGE_SHIFT,
2653 		 (range->end - 1) >> PAGE_SHIFT,
2654 		 mni->interval_tree.start >> PAGE_SHIFT,
2655 		 mni->interval_tree.last >> PAGE_SHIFT, range->event);
2656 
2657 	prange = container_of(mni, struct svm_range, notifier);
2658 
2659 	svm_range_lock(prange);
2660 	mmu_interval_set_seq(mni, cur_seq);
2661 
2662 	switch (range->event) {
2663 	case MMU_NOTIFY_UNMAP:
2664 		svm_range_unmap_from_cpu(mni->mm, prange, start, last);
2665 		break;
2666 	default:
2667 		svm_range_evict(prange, mni->mm, start, last, range->event);
2668 		break;
2669 	}
2670 
2671 	svm_range_unlock(prange);
2672 
2673 	return true;
2674 }
2675 
2676 /**
2677  * svm_range_from_addr - find svm range from fault address
2678  * @svms: svm range list header
2679  * @addr: address to search range interval tree, in pages
2680  * @parent: parent range if range is on child list
2681  *
2682  * Context: The caller must hold svms->lock
2683  *
2684  * Return: the svm_range found or NULL
2685  */
2686 struct svm_range *
2687 svm_range_from_addr(struct svm_range_list *svms, unsigned long addr,
2688 		    struct svm_range **parent)
2689 {
2690 	struct interval_tree_node *node;
2691 	struct svm_range *prange;
2692 	struct svm_range *pchild;
2693 
2694 	node = interval_tree_iter_first(&svms->objects, addr, addr);
2695 	if (!node)
2696 		return NULL;
2697 
2698 	prange = container_of(node, struct svm_range, it_node);
2699 	pr_debug("address 0x%lx prange [0x%lx 0x%lx] node [0x%lx 0x%lx]\n",
2700 		 addr, prange->start, prange->last, node->start, node->last);
2701 
2702 	if (addr >= prange->start && addr <= prange->last) {
2703 		if (parent)
2704 			*parent = prange;
2705 		return prange;
2706 	}
2707 	list_for_each_entry(pchild, &prange->child_list, child_list)
2708 		if (addr >= pchild->start && addr <= pchild->last) {
2709 			pr_debug("found address 0x%lx pchild [0x%lx 0x%lx]\n",
2710 				 addr, pchild->start, pchild->last);
2711 			if (parent)
2712 				*parent = prange;
2713 			return pchild;
2714 		}
2715 
2716 	return NULL;
2717 }
2718 
2719 /* svm_range_best_restore_location - decide the best fault restore location
2720  * @prange: svm range structure
2721  * @adev: the GPU on which vm fault happened
2722  *
2723  * This is only called when xnack is on, to decide the best location to restore
2724  * the range mapping after GPU vm fault. Caller uses the best location to do
2725  * migration if actual loc is not best location, then update GPU page table
2726  * mapping to the best location.
2727  *
2728  * If the preferred loc is accessible by faulting GPU, use preferred loc.
2729  * If vm fault gpu idx is on range ACCESSIBLE bitmap, best_loc is vm fault gpu
2730  * If vm fault gpu idx is on range ACCESSIBLE_IN_PLACE bitmap, then
2731  *    if range actual loc is cpu, best_loc is cpu
2732  *    if vm fault gpu is on xgmi same hive of range actual loc gpu, best_loc is
2733  *    range actual loc.
2734  * Otherwise, GPU no access, best_loc is -1.
2735  *
2736  * Return:
2737  * -1 means vm fault GPU no access
2738  * 0 for CPU or GPU id
2739  */
2740 static int32_t
2741 svm_range_best_restore_location(struct svm_range *prange,
2742 				struct kfd_node *node,
2743 				int32_t *gpuidx)
2744 {
2745 	struct kfd_node *bo_node, *preferred_node;
2746 	struct kfd_process *p;
2747 	uint32_t gpuid;
2748 	int r;
2749 
2750 	p = container_of(prange->svms, struct kfd_process, svms);
2751 
2752 	r = kfd_process_gpuid_from_node(p, node, &gpuid, gpuidx);
2753 	if (r < 0) {
2754 		pr_debug("failed to get gpuid from kgd\n");
2755 		return -1;
2756 	}
2757 
2758 	if (node->adev->apu_prefer_gtt)
2759 		return 0;
2760 
2761 	if (prange->preferred_loc == gpuid ||
2762 	    prange->preferred_loc == KFD_IOCTL_SVM_LOCATION_SYSMEM) {
2763 		return prange->preferred_loc;
2764 	} else if (prange->preferred_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
2765 		preferred_node = svm_range_get_node_by_id(prange, prange->preferred_loc);
2766 		if (preferred_node && svm_nodes_in_same_hive(node, preferred_node))
2767 			return prange->preferred_loc;
2768 		/* fall through */
2769 	}
2770 
2771 	if (test_bit(*gpuidx, prange->bitmap_access))
2772 		return gpuid;
2773 
2774 	if (test_bit(*gpuidx, prange->bitmap_aip)) {
2775 		if (!prange->actual_loc)
2776 			return 0;
2777 
2778 		bo_node = svm_range_get_node_by_id(prange, prange->actual_loc);
2779 		if (bo_node && svm_nodes_in_same_hive(node, bo_node))
2780 			return prange->actual_loc;
2781 		else
2782 			return 0;
2783 	}
2784 
2785 	return -1;
2786 }
2787 
2788 static int
2789 svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
2790 			       unsigned long *start, unsigned long *last,
2791 			       bool *is_heap_stack)
2792 {
2793 	struct vm_area_struct *vma;
2794 	struct interval_tree_node *node;
2795 	struct rb_node *rb_node;
2796 	unsigned long start_limit, end_limit;
2797 
2798 	vma = vma_lookup(p->mm, addr << PAGE_SHIFT);
2799 	if (!vma) {
2800 		pr_debug("VMA does not exist in address [0x%llx]\n", addr);
2801 		return -EFAULT;
2802 	}
2803 
2804 	*is_heap_stack = vma_is_initial_heap(vma) || vma_is_initial_stack(vma);
2805 
2806 	start_limit = max(vma->vm_start >> PAGE_SHIFT,
2807 		      (unsigned long)ALIGN_DOWN(addr, 1UL << p->svms.default_granularity));
2808 	end_limit = min(vma->vm_end >> PAGE_SHIFT,
2809 		    (unsigned long)ALIGN(addr + 1, 1UL << p->svms.default_granularity));
2810 
2811 	/* First range that starts after the fault address */
2812 	node = interval_tree_iter_first(&p->svms.objects, addr + 1, ULONG_MAX);
2813 	if (node) {
2814 		end_limit = min(end_limit, node->start);
2815 		/* Last range that ends before the fault address */
2816 		rb_node = rb_prev(&node->rb);
2817 	} else {
2818 		/* Last range must end before addr because
2819 		 * there was no range after addr
2820 		 */
2821 		rb_node = rb_last(&p->svms.objects.rb_root);
2822 	}
2823 	if (rb_node) {
2824 		node = container_of(rb_node, struct interval_tree_node, rb);
2825 		if (node->last >= addr) {
2826 			WARN(1, "Overlap with prev node and page fault addr\n");
2827 			return -EFAULT;
2828 		}
2829 		start_limit = max(start_limit, node->last + 1);
2830 	}
2831 
2832 	*start = start_limit;
2833 	*last = end_limit - 1;
2834 
2835 	pr_debug("vma [0x%lx 0x%lx] range [0x%lx 0x%lx] is_heap_stack %d\n",
2836 		 vma->vm_start >> PAGE_SHIFT, vma->vm_end >> PAGE_SHIFT,
2837 		 *start, *last, *is_heap_stack);
2838 
2839 	return 0;
2840 }
2841 
2842 static int
2843 svm_range_check_vm_userptr(struct kfd_process *p, uint64_t start, uint64_t last,
2844 			   uint64_t *bo_s, uint64_t *bo_l)
2845 {
2846 	struct amdgpu_bo_va_mapping *mapping;
2847 	struct interval_tree_node *node;
2848 	struct amdgpu_bo *bo = NULL;
2849 	unsigned long userptr;
2850 	uint32_t i;
2851 	int r;
2852 
2853 	for (i = 0; i < p->n_pdds; i++) {
2854 		struct amdgpu_vm *vm;
2855 
2856 		if (!p->pdds[i]->drm_priv)
2857 			continue;
2858 
2859 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
2860 		r = amdgpu_bo_reserve(vm->root.bo, false);
2861 		if (r)
2862 			return r;
2863 
2864 		/* Check userptr by searching entire vm->va interval tree */
2865 		node = interval_tree_iter_first(&vm->va, 0, ~0ULL);
2866 		while (node) {
2867 			mapping = container_of((struct rb_node *)node,
2868 					       struct amdgpu_bo_va_mapping, rb);
2869 			bo = mapping->bo_va->base.bo;
2870 
2871 			if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm,
2872 							 start << PAGE_SHIFT,
2873 							 last << PAGE_SHIFT,
2874 							 &userptr)) {
2875 				node = interval_tree_iter_next(node, 0, ~0ULL);
2876 				continue;
2877 			}
2878 
2879 			pr_debug("[0x%llx 0x%llx] already userptr mapped\n",
2880 				 start, last);
2881 			if (bo_s && bo_l) {
2882 				*bo_s = userptr >> PAGE_SHIFT;
2883 				*bo_l = *bo_s + bo->tbo.ttm->num_pages - 1;
2884 			}
2885 			amdgpu_bo_unreserve(vm->root.bo);
2886 			return -EADDRINUSE;
2887 		}
2888 		amdgpu_bo_unreserve(vm->root.bo);
2889 	}
2890 	return 0;
2891 }
2892 
2893 static struct
2894 svm_range *svm_range_create_unregistered_range(struct kfd_node *node,
2895 						struct kfd_process *p,
2896 						struct mm_struct *mm,
2897 						int64_t addr)
2898 {
2899 	struct svm_range *prange = NULL;
2900 	unsigned long start, last;
2901 	uint32_t gpuid, gpuidx;
2902 	bool is_heap_stack;
2903 	uint64_t bo_s = 0;
2904 	uint64_t bo_l = 0;
2905 	int r;
2906 
2907 	if (svm_range_get_range_boundaries(p, addr, &start, &last,
2908 					   &is_heap_stack))
2909 		return NULL;
2910 
2911 	r = svm_range_check_vm(p, start, last, &bo_s, &bo_l);
2912 	if (r != -EADDRINUSE)
2913 		r = svm_range_check_vm_userptr(p, start, last, &bo_s, &bo_l);
2914 
2915 	if (r == -EADDRINUSE) {
2916 		if (addr >= bo_s && addr <= bo_l)
2917 			return NULL;
2918 
2919 		/* Create one page svm range if 2MB range overlapping */
2920 		start = addr;
2921 		last = addr;
2922 	}
2923 
2924 	prange = svm_range_new(&p->svms, start, last, true);
2925 	if (!prange) {
2926 		pr_debug("Failed to create prange in address [0x%llx]\n", addr);
2927 		return NULL;
2928 	}
2929 	if (kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx)) {
2930 		pr_debug("failed to get gpuid from kgd\n");
2931 		svm_range_free(prange, true);
2932 		return NULL;
2933 	}
2934 
2935 	if (is_heap_stack)
2936 		prange->preferred_loc = KFD_IOCTL_SVM_LOCATION_SYSMEM;
2937 
2938 	svm_range_add_to_svms(prange);
2939 	svm_range_add_notifier_locked(mm, prange);
2940 
2941 	return prange;
2942 }
2943 
2944 /* svm_range_skip_recover - decide if prange can be recovered
2945  * @prange: svm range structure
2946  *
2947  * GPU vm retry fault handle skip recover the range for cases:
2948  * 1. prange is on deferred list to be removed after unmap, it is stale fault,
2949  *    deferred list work will drain the stale fault before free the prange.
2950  * 2. prange is on deferred list to add interval notifier after split, or
2951  * 3. prange is child range, it is split from parent prange, recover later
2952  *    after interval notifier is added.
2953  *
2954  * Return: true to skip recover, false to recover
2955  */
2956 static bool svm_range_skip_recover(struct svm_range *prange)
2957 {
2958 	struct svm_range_list *svms = prange->svms;
2959 
2960 	spin_lock(&svms->deferred_list_lock);
2961 	if (list_empty(&prange->deferred_list) &&
2962 	    list_empty(&prange->child_list)) {
2963 		spin_unlock(&svms->deferred_list_lock);
2964 		return false;
2965 	}
2966 	spin_unlock(&svms->deferred_list_lock);
2967 
2968 	if (prange->work_item.op == SVM_OP_UNMAP_RANGE) {
2969 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] unmapped\n",
2970 			 svms, prange, prange->start, prange->last);
2971 		return true;
2972 	}
2973 	if (prange->work_item.op == SVM_OP_ADD_RANGE_AND_MAP ||
2974 	    prange->work_item.op == SVM_OP_ADD_RANGE) {
2975 		pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] not added yet\n",
2976 			 svms, prange, prange->start, prange->last);
2977 		return true;
2978 	}
2979 	return false;
2980 }
2981 
2982 static void
2983 svm_range_count_fault(struct kfd_node *node, struct kfd_process *p,
2984 		      int32_t gpuidx)
2985 {
2986 	struct kfd_process_device *pdd;
2987 
2988 	/* fault is on different page of same range
2989 	 * or fault is skipped to recover later
2990 	 * or fault is on invalid virtual address
2991 	 */
2992 	if (gpuidx == MAX_GPU_INSTANCE) {
2993 		uint32_t gpuid;
2994 		int r;
2995 
2996 		r = kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx);
2997 		if (r < 0)
2998 			return;
2999 	}
3000 
3001 	/* fault is recovered
3002 	 * or fault cannot recover because GPU no access on the range
3003 	 */
3004 	pdd = kfd_process_device_from_gpuidx(p, gpuidx);
3005 	if (pdd)
3006 		WRITE_ONCE(pdd->faults, pdd->faults + 1);
3007 }
3008 
3009 static bool
3010 svm_fault_allowed(struct vm_area_struct *vma, bool write_fault)
3011 {
3012 	unsigned long requested = VM_READ;
3013 
3014 	if (write_fault)
3015 		requested |= VM_WRITE;
3016 
3017 	pr_debug("requested 0x%lx, vma permission flags 0x%lx\n", requested,
3018 		vma->vm_flags);
3019 	return (vma->vm_flags & requested) == requested;
3020 }
3021 
3022 int
3023 svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
3024 			uint32_t vmid, uint32_t node_id,
3025 			uint64_t addr, uint64_t ts, bool write_fault)
3026 {
3027 	unsigned long start, last, size;
3028 	struct mm_struct *mm = NULL;
3029 	struct svm_range_list *svms;
3030 	struct svm_range *prange;
3031 	struct kfd_process *p;
3032 	ktime_t timestamp = ktime_get_boottime();
3033 	struct kfd_node *node;
3034 	int32_t best_loc;
3035 	int32_t gpuid, gpuidx = MAX_GPU_INSTANCE;
3036 	bool write_locked = false;
3037 	struct vm_area_struct *vma;
3038 	bool migration = false;
3039 	int r = 0;
3040 
3041 	if (!KFD_IS_SVM_API_SUPPORTED(adev)) {
3042 		pr_debug("device does not support SVM\n");
3043 		return -EFAULT;
3044 	}
3045 
3046 	p = kfd_lookup_process_by_pasid(pasid, NULL);
3047 	if (!p) {
3048 		pr_debug("kfd process not founded pasid 0x%x\n", pasid);
3049 		return 0;
3050 	}
3051 	svms = &p->svms;
3052 
3053 	pr_debug("restoring svms 0x%p fault address 0x%llx\n", svms, addr);
3054 
3055 	if (atomic_read(&svms->drain_pagefaults)) {
3056 		pr_debug("page fault handling disabled, drop fault 0x%llx\n", addr);
3057 		r = 0;
3058 		goto out;
3059 	}
3060 
3061 	node = kfd_node_by_irq_ids(adev, node_id, vmid);
3062 	if (!node) {
3063 		pr_debug("kfd node does not exist node_id: %d, vmid: %d\n", node_id,
3064 			 vmid);
3065 		r = -EFAULT;
3066 		goto out;
3067 	}
3068 
3069 	if (kfd_process_gpuid_from_node(p, node, &gpuid, &gpuidx)) {
3070 		pr_debug("failed to get gpuid/gpuidex for node_id: %d\n", node_id);
3071 		r = -EFAULT;
3072 		goto out;
3073 	}
3074 
3075 	if (!p->xnack_enabled) {
3076 		pr_debug("XNACK not enabled for pasid 0x%x\n", pasid);
3077 		r = -EFAULT;
3078 		goto out;
3079 	}
3080 
3081 	/* p->lead_thread is available as kfd_process_wq_release flush the work
3082 	 * before releasing task ref.
3083 	 */
3084 	mm = get_task_mm(p->lead_thread);
3085 	if (!mm) {
3086 		pr_debug("svms 0x%p failed to get mm\n", svms);
3087 		r = 0;
3088 		goto out;
3089 	}
3090 
3091 	mmap_read_lock(mm);
3092 retry_write_locked:
3093 	mutex_lock(&svms->lock);
3094 
3095 	/* check if this page fault time stamp is before svms->checkpoint_ts */
3096 	if (svms->checkpoint_ts[gpuidx] != 0) {
3097 		if (amdgpu_ih_ts_after_or_equal(ts,  svms->checkpoint_ts[gpuidx])) {
3098 			pr_debug("draining retry fault, drop fault 0x%llx\n", addr);
3099 			if (write_locked)
3100 				mmap_write_downgrade(mm);
3101 			r = -EAGAIN;
3102 			goto out_unlock_svms;
3103 		} else {
3104 			/* ts is after svms->checkpoint_ts now, reset svms->checkpoint_ts
3105 			 * to zero to avoid following ts wrap around give wrong comparing
3106 			 */
3107 			svms->checkpoint_ts[gpuidx] = 0;
3108 		}
3109 	}
3110 
3111 	prange = svm_range_from_addr(svms, addr, NULL);
3112 	if (!prange) {
3113 		pr_debug("failed to find prange svms 0x%p address [0x%llx]\n",
3114 			 svms, addr);
3115 		if (!write_locked) {
3116 			/* Need the write lock to create new range with MMU notifier.
3117 			 * Also flush pending deferred work to make sure the interval
3118 			 * tree is up to date before we add a new range
3119 			 */
3120 			mutex_unlock(&svms->lock);
3121 			mmap_read_unlock(mm);
3122 			mmap_write_lock(mm);
3123 			write_locked = true;
3124 			goto retry_write_locked;
3125 		}
3126 		prange = svm_range_create_unregistered_range(node, p, mm, addr);
3127 		if (!prange) {
3128 			pr_debug("failed to create unregistered range svms 0x%p address [0x%llx]\n",
3129 				 svms, addr);
3130 			mmap_write_downgrade(mm);
3131 			r = -EFAULT;
3132 			goto out_unlock_svms;
3133 		}
3134 	}
3135 	if (write_locked)
3136 		mmap_write_downgrade(mm);
3137 
3138 	mutex_lock(&prange->migrate_mutex);
3139 
3140 	if (svm_range_skip_recover(prange)) {
3141 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
3142 		r = 0;
3143 		goto out_unlock_range;
3144 	}
3145 
3146 	/* skip duplicate vm fault on different pages of same range */
3147 	if (ktime_before(timestamp, ktime_add_ns(prange->validate_timestamp,
3148 				AMDGPU_SVM_RANGE_RETRY_FAULT_PENDING))) {
3149 		pr_debug("svms 0x%p [0x%lx %lx] already restored\n",
3150 			 svms, prange->start, prange->last);
3151 		r = 0;
3152 		goto out_unlock_range;
3153 	}
3154 
3155 	/* __do_munmap removed VMA, return success as we are handling stale
3156 	 * retry fault.
3157 	 */
3158 	vma = vma_lookup(mm, addr << PAGE_SHIFT);
3159 	if (!vma) {
3160 		pr_debug("address 0x%llx VMA is removed\n", addr);
3161 		r = 0;
3162 		goto out_unlock_range;
3163 	}
3164 
3165 	if (!svm_fault_allowed(vma, write_fault)) {
3166 		pr_debug("fault addr 0x%llx no %s permission\n", addr,
3167 			write_fault ? "write" : "read");
3168 		r = -EPERM;
3169 		goto out_unlock_range;
3170 	}
3171 
3172 	best_loc = svm_range_best_restore_location(prange, node, &gpuidx);
3173 	if (best_loc == -1) {
3174 		pr_debug("svms %p failed get best restore loc [0x%lx 0x%lx]\n",
3175 			 svms, prange->start, prange->last);
3176 		r = -EACCES;
3177 		goto out_unlock_range;
3178 	}
3179 
3180 	pr_debug("svms %p [0x%lx 0x%lx] best restore 0x%x, actual loc 0x%x\n",
3181 		 svms, prange->start, prange->last, best_loc,
3182 		 prange->actual_loc);
3183 
3184 	kfd_smi_event_page_fault_start(node, p->lead_thread->pid, addr,
3185 				       write_fault, timestamp);
3186 
3187 	/* Align migration range start and size to granularity size */
3188 	size = 1UL << prange->granularity;
3189 	start = max_t(unsigned long, ALIGN_DOWN(addr, size), prange->start);
3190 	last = min_t(unsigned long, ALIGN(addr + 1, size) - 1, prange->last);
3191 	if (prange->actual_loc != 0 || best_loc != 0) {
3192 		if (best_loc) {
3193 			r = svm_migrate_to_vram(prange, best_loc, start, last,
3194 					mm, KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU);
3195 			if (r) {
3196 				pr_debug("svm_migrate_to_vram failed (%d) at %llx, falling back to system memory\n",
3197 					 r, addr);
3198 				/* Fallback to system memory if migration to
3199 				 * VRAM failed
3200 				 */
3201 				if (prange->actual_loc && prange->actual_loc != best_loc)
3202 					r = svm_migrate_vram_to_ram(prange, mm, start, last,
3203 						KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU, NULL);
3204 				else
3205 					r = 0;
3206 			}
3207 		} else {
3208 			r = svm_migrate_vram_to_ram(prange, mm, start, last,
3209 					KFD_MIGRATE_TRIGGER_PAGEFAULT_GPU, NULL);
3210 		}
3211 		if (r) {
3212 			pr_debug("failed %d to migrate svms %p [0x%lx 0x%lx]\n",
3213 				 r, svms, start, last);
3214 			goto out_migrate_fail;
3215 		} else {
3216 			migration = true;
3217 		}
3218 	}
3219 
3220 	r = svm_range_validate_and_map(mm, start, last, prange, gpuidx, false,
3221 				       false, false);
3222 	if (r)
3223 		pr_debug("failed %d to map svms 0x%p [0x%lx 0x%lx] to gpus\n",
3224 			 r, svms, start, last);
3225 
3226 out_migrate_fail:
3227 	kfd_smi_event_page_fault_end(node, p->lead_thread->pid, addr,
3228 				     migration);
3229 
3230 out_unlock_range:
3231 	mutex_unlock(&prange->migrate_mutex);
3232 out_unlock_svms:
3233 	mutex_unlock(&svms->lock);
3234 	mmap_read_unlock(mm);
3235 
3236 	if (r != -EAGAIN)
3237 		svm_range_count_fault(node, p, gpuidx);
3238 
3239 	mmput(mm);
3240 out:
3241 	kfd_unref_process(p);
3242 
3243 	if (r == -EAGAIN) {
3244 		pr_debug("recover vm fault later\n");
3245 		amdgpu_gmc_filter_faults_remove(node->adev, addr, pasid);
3246 		r = 0;
3247 	}
3248 	return r;
3249 }
3250 
3251 int
3252 svm_range_switch_xnack_reserve_mem(struct kfd_process *p, bool xnack_enabled)
3253 {
3254 	struct svm_range *prange, *pchild;
3255 	uint64_t reserved_size = 0;
3256 	uint64_t size;
3257 	int r = 0;
3258 
3259 	pr_debug("switching xnack from %d to %d\n", p->xnack_enabled, xnack_enabled);
3260 
3261 	mutex_lock(&p->svms.lock);
3262 
3263 	list_for_each_entry(prange, &p->svms.list, list) {
3264 		svm_range_lock(prange);
3265 		list_for_each_entry(pchild, &prange->child_list, child_list) {
3266 			size = (pchild->last - pchild->start + 1) << PAGE_SHIFT;
3267 			if (xnack_enabled) {
3268 				amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
3269 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3270 			} else {
3271 				r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
3272 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3273 				if (r)
3274 					goto out_unlock;
3275 				reserved_size += size;
3276 			}
3277 		}
3278 
3279 		size = (prange->last - prange->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 out_unlock:
3291 		svm_range_unlock(prange);
3292 		if (r)
3293 			break;
3294 	}
3295 
3296 	if (r)
3297 		amdgpu_amdkfd_unreserve_mem_limit(NULL, reserved_size,
3298 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR, 0);
3299 	else
3300 		/* Change xnack mode must be inside svms lock, to avoid race with
3301 		 * svm_range_deferred_list_work unreserve memory in parallel.
3302 		 */
3303 		p->xnack_enabled = xnack_enabled;
3304 
3305 	mutex_unlock(&p->svms.lock);
3306 	return r;
3307 }
3308 
3309 void svm_range_list_fini(struct kfd_process *p)
3310 {
3311 	struct svm_range *prange;
3312 	struct svm_range *next;
3313 
3314 	pr_debug("process pid %d svms 0x%p\n", p->lead_thread->pid,
3315 		 &p->svms);
3316 
3317 	cancel_delayed_work_sync(&p->svms.restore_work);
3318 
3319 	/* Ensure list work is finished before process is destroyed */
3320 	flush_work(&p->svms.deferred_list_work);
3321 
3322 	/*
3323 	 * Ensure no retry fault comes in afterwards, as page fault handler will
3324 	 * not find kfd process and take mm lock to recover fault.
3325 	 * stop kfd page fault handing, then wait pending page faults got drained
3326 	 */
3327 	atomic_set(&p->svms.drain_pagefaults, 1);
3328 	svm_range_drain_retry_fault(&p->svms);
3329 
3330 	list_for_each_entry_safe(prange, next, &p->svms.list, list) {
3331 		svm_range_unlink(prange);
3332 		svm_range_remove_notifier(prange);
3333 		svm_range_free(prange, true);
3334 	}
3335 
3336 	mutex_destroy(&p->svms.lock);
3337 
3338 	pr_debug("process pid %d svms 0x%p done\n",
3339 		p->lead_thread->pid, &p->svms);
3340 }
3341 
3342 int svm_range_list_init(struct kfd_process *p)
3343 {
3344 	struct svm_range_list *svms = &p->svms;
3345 	int i;
3346 
3347 	svms->objects = RB_ROOT_CACHED;
3348 	mutex_init(&svms->lock);
3349 	INIT_LIST_HEAD(&svms->list);
3350 	atomic_set(&svms->evicted_ranges, 0);
3351 	atomic_set(&svms->drain_pagefaults, 0);
3352 	INIT_DELAYED_WORK(&svms->restore_work, svm_range_restore_work);
3353 	INIT_WORK(&svms->deferred_list_work, svm_range_deferred_list_work);
3354 	INIT_LIST_HEAD(&svms->deferred_range_list);
3355 	INIT_LIST_HEAD(&svms->criu_svm_metadata_list);
3356 	spin_lock_init(&svms->deferred_list_lock);
3357 
3358 	for (i = 0; i < p->n_pdds; i++)
3359 		if (KFD_IS_SVM_API_SUPPORTED(p->pdds[i]->dev->adev))
3360 			bitmap_set(svms->bitmap_supported, i, 1);
3361 
3362 	 /* Value of default granularity cannot exceed 0x1B, the
3363 	  * number of pages supported by a 4-level paging table
3364 	  */
3365 	svms->default_granularity = min_t(u8, amdgpu_svm_default_granularity, 0x1B);
3366 	pr_debug("Default SVM Granularity to use: %d\n", svms->default_granularity);
3367 
3368 	return 0;
3369 }
3370 
3371 /**
3372  * svm_range_check_vm - check if virtual address range mapped already
3373  * @p: current kfd_process
3374  * @start: range start address, in pages
3375  * @last: range last address, in pages
3376  * @bo_s: mapping start address in pages if address range already mapped
3377  * @bo_l: mapping last address in pages if address range already mapped
3378  *
3379  * The purpose is to avoid virtual address ranges already allocated by
3380  * kfd_ioctl_alloc_memory_of_gpu ioctl.
3381  * It looks for each pdd in the kfd_process.
3382  *
3383  * Context: Process context
3384  *
3385  * Return 0 - OK, if the range is not mapped.
3386  * Otherwise error code:
3387  * -EADDRINUSE - if address is mapped already by kfd_ioctl_alloc_memory_of_gpu
3388  * -ERESTARTSYS - A wait for the buffer to become unreserved was interrupted by
3389  * a signal. Release all buffer reservations and return to user-space.
3390  */
3391 static int
3392 svm_range_check_vm(struct kfd_process *p, uint64_t start, uint64_t last,
3393 		   uint64_t *bo_s, uint64_t *bo_l)
3394 {
3395 	struct amdgpu_bo_va_mapping *mapping;
3396 	struct interval_tree_node *node;
3397 	uint32_t i;
3398 	int r;
3399 
3400 	for (i = 0; i < p->n_pdds; i++) {
3401 		struct amdgpu_vm *vm;
3402 
3403 		if (!p->pdds[i]->drm_priv)
3404 			continue;
3405 
3406 		vm = drm_priv_to_vm(p->pdds[i]->drm_priv);
3407 		r = amdgpu_bo_reserve(vm->root.bo, false);
3408 		if (r)
3409 			return r;
3410 
3411 		node = interval_tree_iter_first(&vm->va, start, last);
3412 		if (node) {
3413 			pr_debug("range [0x%llx 0x%llx] already TTM mapped\n",
3414 				 start, last);
3415 			mapping = container_of((struct rb_node *)node,
3416 					       struct amdgpu_bo_va_mapping, rb);
3417 			if (bo_s && bo_l) {
3418 				*bo_s = mapping->start;
3419 				*bo_l = mapping->last;
3420 			}
3421 			amdgpu_bo_unreserve(vm->root.bo);
3422 			return -EADDRINUSE;
3423 		}
3424 		amdgpu_bo_unreserve(vm->root.bo);
3425 	}
3426 
3427 	return 0;
3428 }
3429 
3430 /**
3431  * svm_range_is_valid - check if virtual address range is valid
3432  * @p: current kfd_process
3433  * @start: range start address, in pages
3434  * @size: range size, in pages
3435  *
3436  * Valid virtual address range means it belongs to one or more VMAs
3437  *
3438  * Context: Process context
3439  *
3440  * Return:
3441  *  0 - OK, otherwise error code
3442  */
3443 static int
3444 svm_range_is_valid(struct kfd_process *p, uint64_t start, uint64_t size)
3445 {
3446 	const unsigned long device_vma = VM_IO | VM_PFNMAP | VM_MIXEDMAP;
3447 	struct vm_area_struct *vma;
3448 	unsigned long end;
3449 	unsigned long start_unchg = start;
3450 
3451 	start <<= PAGE_SHIFT;
3452 	end = start + (size << PAGE_SHIFT);
3453 	do {
3454 		vma = vma_lookup(p->mm, start);
3455 		if (!vma || (vma->vm_flags & device_vma))
3456 			return -EFAULT;
3457 		start = min(end, vma->vm_end);
3458 	} while (start < end);
3459 
3460 	return svm_range_check_vm(p, start_unchg, (end - 1) >> PAGE_SHIFT, NULL,
3461 				  NULL);
3462 }
3463 
3464 /**
3465  * svm_range_best_prefetch_location - decide the best prefetch location
3466  * @prange: svm range structure
3467  *
3468  * For xnack off:
3469  * If range map to single GPU, the best prefetch location is prefetch_loc, which
3470  * can be CPU or GPU.
3471  *
3472  * If range is ACCESS or ACCESS_IN_PLACE by mGPUs, only if mGPU connection on
3473  * XGMI same hive, the best prefetch location is prefetch_loc GPU, othervise
3474  * the best prefetch location is always CPU, because GPU can not have coherent
3475  * mapping VRAM of other GPUs even with large-BAR PCIe connection.
3476  *
3477  * For xnack on:
3478  * If range is not ACCESS_IN_PLACE by mGPUs, the best prefetch location is
3479  * prefetch_loc, other GPU access will generate vm fault and trigger migration.
3480  *
3481  * If range is ACCESS_IN_PLACE by mGPUs, only if mGPU connection on XGMI same
3482  * hive, the best prefetch location is prefetch_loc GPU, otherwise the best
3483  * prefetch location is always CPU.
3484  *
3485  * Context: Process context
3486  *
3487  * Return:
3488  * 0 for CPU or GPU id
3489  */
3490 static uint32_t
3491 svm_range_best_prefetch_location(struct svm_range *prange)
3492 {
3493 	DECLARE_BITMAP(bitmap, MAX_GPU_INSTANCE);
3494 	uint32_t best_loc = prange->prefetch_loc;
3495 	struct kfd_process_device *pdd;
3496 	struct kfd_node *bo_node;
3497 	struct kfd_process *p;
3498 	uint32_t gpuidx;
3499 
3500 	p = container_of(prange->svms, struct kfd_process, svms);
3501 
3502 	if (!best_loc || best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED)
3503 		goto out;
3504 
3505 	bo_node = svm_range_get_node_by_id(prange, best_loc);
3506 	if (!bo_node) {
3507 		WARN_ONCE(1, "failed to get valid kfd node at id%x\n", best_loc);
3508 		best_loc = 0;
3509 		goto out;
3510 	}
3511 
3512 	if (bo_node->adev->apu_prefer_gtt) {
3513 		best_loc = 0;
3514 		goto out;
3515 	}
3516 
3517 	if (p->xnack_enabled)
3518 		bitmap_copy(bitmap, prange->bitmap_aip, MAX_GPU_INSTANCE);
3519 	else
3520 		bitmap_or(bitmap, prange->bitmap_access, prange->bitmap_aip,
3521 			  MAX_GPU_INSTANCE);
3522 
3523 	for_each_set_bit(gpuidx, bitmap, MAX_GPU_INSTANCE) {
3524 		pdd = kfd_process_device_from_gpuidx(p, gpuidx);
3525 		if (!pdd) {
3526 			pr_debug("failed to get device by idx 0x%x\n", gpuidx);
3527 			continue;
3528 		}
3529 
3530 		if (pdd->dev->adev == bo_node->adev)
3531 			continue;
3532 
3533 		if (!svm_nodes_in_same_hive(pdd->dev, bo_node)) {
3534 			best_loc = 0;
3535 			break;
3536 		}
3537 	}
3538 
3539 out:
3540 	pr_debug("xnack %d svms 0x%p [0x%lx 0x%lx] best loc 0x%x\n",
3541 		 p->xnack_enabled, &p->svms, prange->start, prange->last,
3542 		 best_loc);
3543 
3544 	return best_loc;
3545 }
3546 
3547 /* svm_range_trigger_migration - start page migration if prefetch loc changed
3548  * @mm: current process mm_struct
3549  * @prange: svm range structure
3550  * @migrated: output, true if migration is triggered
3551  *
3552  * If range perfetch_loc is GPU, actual loc is cpu 0, then migrate the range
3553  * from ram to vram.
3554  * If range prefetch_loc is cpu 0, actual loc is GPU, then migrate the range
3555  * from vram to ram.
3556  *
3557  * If GPU vm fault retry is not enabled, migration interact with MMU notifier
3558  * and restore work:
3559  * 1. migrate_vma_setup invalidate pages, MMU notifier callback svm_range_evict
3560  *    stops all queues, schedule restore work
3561  * 2. svm_range_restore_work wait for migration is done by
3562  *    a. svm_range_validate_vram takes prange->migrate_mutex
3563  *    b. svm_range_validate_ram HMM get pages wait for CPU fault handle returns
3564  * 3. restore work update mappings of GPU, resume all queues.
3565  *
3566  * Context: Process context
3567  *
3568  * Return:
3569  * 0 - OK, otherwise - error code of migration
3570  */
3571 static int
3572 svm_range_trigger_migration(struct mm_struct *mm, struct svm_range *prange,
3573 			    bool *migrated)
3574 {
3575 	uint32_t best_loc;
3576 	int r = 0;
3577 
3578 	*migrated = false;
3579 	best_loc = svm_range_best_prefetch_location(prange);
3580 
3581 	/* when best_loc is a gpu node and same as prange->actual_loc
3582 	 * we still need do migration as prange->actual_loc !=0 does
3583 	 * not mean all pages in prange are vram. hmm migrate will pick
3584 	 * up right pages during migration.
3585 	 */
3586 	if ((best_loc == KFD_IOCTL_SVM_LOCATION_UNDEFINED) ||
3587 	    (best_loc == 0 && prange->actual_loc == 0))
3588 		return 0;
3589 
3590 	if (!best_loc) {
3591 		r = svm_migrate_vram_to_ram(prange, mm, prange->start, prange->last,
3592 					KFD_MIGRATE_TRIGGER_PREFETCH, NULL);
3593 		*migrated = !r;
3594 		return r;
3595 	}
3596 
3597 	r = svm_migrate_to_vram(prange, best_loc, prange->start, prange->last,
3598 				mm, KFD_MIGRATE_TRIGGER_PREFETCH);
3599 	*migrated = !r;
3600 
3601 	return 0;
3602 }
3603 
3604 int svm_range_schedule_evict_svm_bo(struct amdgpu_amdkfd_fence *fence)
3605 {
3606 	/* Dereferencing fence->svm_bo is safe here because the fence hasn't
3607 	 * signaled yet and we're under the protection of the fence->lock.
3608 	 * After the fence is signaled in svm_range_bo_release, we cannot get
3609 	 * here any more.
3610 	 *
3611 	 * Reference is dropped in svm_range_evict_svm_bo_worker.
3612 	 */
3613 	if (svm_bo_ref_unless_zero(fence->svm_bo)) {
3614 		WRITE_ONCE(fence->svm_bo->evicting, 1);
3615 		schedule_work(&fence->svm_bo->eviction_work);
3616 	}
3617 
3618 	return 0;
3619 }
3620 
3621 static void svm_range_evict_svm_bo_worker(struct work_struct *work)
3622 {
3623 	struct svm_range_bo *svm_bo;
3624 	struct mm_struct *mm;
3625 	int r = 0;
3626 
3627 	svm_bo = container_of(work, struct svm_range_bo, eviction_work);
3628 
3629 	if (mmget_not_zero(svm_bo->eviction_fence->mm)) {
3630 		mm = svm_bo->eviction_fence->mm;
3631 	} else {
3632 		svm_range_bo_unref(svm_bo);
3633 		return;
3634 	}
3635 
3636 	mmap_read_lock(mm);
3637 	spin_lock(&svm_bo->list_lock);
3638 	while (!list_empty(&svm_bo->range_list) && !r) {
3639 		struct svm_range *prange =
3640 				list_first_entry(&svm_bo->range_list,
3641 						struct svm_range, svm_bo_list);
3642 		int retries = 3;
3643 
3644 		list_del_init(&prange->svm_bo_list);
3645 		spin_unlock(&svm_bo->list_lock);
3646 
3647 		pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms,
3648 			 prange->start, prange->last);
3649 
3650 		mutex_lock(&prange->migrate_mutex);
3651 		do {
3652 			/* migrate all vram pages in this prange to sys ram
3653 			 * after that prange->actual_loc should be zero
3654 			 */
3655 			r = svm_migrate_vram_to_ram(prange, mm,
3656 					prange->start, prange->last,
3657 					KFD_MIGRATE_TRIGGER_TTM_EVICTION, NULL);
3658 		} while (!r && prange->actual_loc && --retries);
3659 
3660 		if (!r && prange->actual_loc)
3661 			pr_info_once("Migration failed during eviction");
3662 
3663 		if (!prange->actual_loc) {
3664 			mutex_lock(&prange->lock);
3665 			prange->svm_bo = NULL;
3666 			mutex_unlock(&prange->lock);
3667 		}
3668 		mutex_unlock(&prange->migrate_mutex);
3669 
3670 		spin_lock(&svm_bo->list_lock);
3671 	}
3672 	spin_unlock(&svm_bo->list_lock);
3673 	mmap_read_unlock(mm);
3674 	mmput(mm);
3675 
3676 	dma_fence_signal(&svm_bo->eviction_fence->base);
3677 
3678 	/* This is the last reference to svm_bo, after svm_range_vram_node_free
3679 	 * has been called in svm_migrate_vram_to_ram
3680 	 */
3681 	WARN_ONCE(!r && kref_read(&svm_bo->kref) != 1, "This was not the last reference\n");
3682 	svm_range_bo_unref(svm_bo);
3683 }
3684 
3685 static int
3686 svm_range_set_attr(struct kfd_process *p, struct mm_struct *mm,
3687 		   uint64_t start, uint64_t size, uint32_t nattr,
3688 		   struct kfd_ioctl_svm_attribute *attrs)
3689 {
3690 	struct amdkfd_process_info *process_info = p->kgd_process_info;
3691 	struct list_head update_list;
3692 	struct list_head insert_list;
3693 	struct list_head remove_list;
3694 	struct list_head remap_list;
3695 	struct svm_range_list *svms;
3696 	struct svm_range *prange;
3697 	struct svm_range *next;
3698 	bool update_mapping = false;
3699 	bool flush_tlb;
3700 	int r, ret = 0;
3701 
3702 	pr_debug("process pid %d svms 0x%p [0x%llx 0x%llx] pages 0x%llx\n",
3703 		 p->lead_thread->pid, &p->svms, start, start + size - 1, size);
3704 
3705 	r = svm_range_check_attr(p, nattr, attrs);
3706 	if (r)
3707 		return r;
3708 
3709 	svms = &p->svms;
3710 
3711 	mutex_lock(&process_info->lock);
3712 
3713 	svm_range_list_lock_and_flush_work(svms, mm);
3714 
3715 	r = svm_range_is_valid(p, start, size);
3716 	if (r) {
3717 		pr_debug("invalid range r=%d\n", r);
3718 		mmap_write_unlock(mm);
3719 		goto out;
3720 	}
3721 
3722 	mutex_lock(&svms->lock);
3723 
3724 	/* Add new range and split existing ranges as needed */
3725 	r = svm_range_add(p, start, size, nattr, attrs, &update_list,
3726 			  &insert_list, &remove_list, &remap_list);
3727 	if (r) {
3728 		mutex_unlock(&svms->lock);
3729 		mmap_write_unlock(mm);
3730 		goto out;
3731 	}
3732 	/* Apply changes as a transaction */
3733 	list_for_each_entry_safe(prange, next, &insert_list, list) {
3734 		svm_range_add_to_svms(prange);
3735 		svm_range_add_notifier_locked(mm, prange);
3736 	}
3737 	list_for_each_entry(prange, &update_list, update_list) {
3738 		svm_range_apply_attrs(p, prange, nattr, attrs, &update_mapping);
3739 		/* TODO: unmap ranges from GPU that lost access */
3740 	}
3741 	update_mapping |= !p->xnack_enabled && !list_empty(&remap_list);
3742 
3743 	list_for_each_entry_safe(prange, next, &remove_list, update_list) {
3744 		pr_debug("unlink old 0x%p prange 0x%p [0x%lx 0x%lx]\n",
3745 			 prange->svms, prange, prange->start,
3746 			 prange->last);
3747 		svm_range_unlink(prange);
3748 		svm_range_remove_notifier(prange);
3749 		svm_range_free(prange, false);
3750 	}
3751 
3752 	mmap_write_downgrade(mm);
3753 	/* Trigger migrations and revalidate and map to GPUs as needed. If
3754 	 * this fails we may be left with partially completed actions. There
3755 	 * is no clean way of rolling back to the previous state in such a
3756 	 * case because the rollback wouldn't be guaranteed to work either.
3757 	 */
3758 	list_for_each_entry(prange, &update_list, update_list) {
3759 		bool migrated;
3760 
3761 		mutex_lock(&prange->migrate_mutex);
3762 
3763 		r = svm_range_trigger_migration(mm, prange, &migrated);
3764 		if (r)
3765 			goto out_unlock_range;
3766 
3767 		if (migrated && (!p->xnack_enabled ||
3768 		    (prange->flags & KFD_IOCTL_SVM_FLAG_GPU_ALWAYS_MAPPED)) &&
3769 		    prange->mapped_to_gpu) {
3770 			pr_debug("restore_work will update mappings of GPUs\n");
3771 			mutex_unlock(&prange->migrate_mutex);
3772 			continue;
3773 		}
3774 
3775 		if (!migrated && !update_mapping) {
3776 			mutex_unlock(&prange->migrate_mutex);
3777 			continue;
3778 		}
3779 
3780 		flush_tlb = !migrated && update_mapping && prange->mapped_to_gpu;
3781 
3782 		r = svm_range_validate_and_map(mm, prange->start, prange->last, prange,
3783 					       MAX_GPU_INSTANCE, true, true, flush_tlb);
3784 		if (r)
3785 			pr_debug("failed %d to map svm range\n", r);
3786 
3787 out_unlock_range:
3788 		mutex_unlock(&prange->migrate_mutex);
3789 		if (r)
3790 			ret = r;
3791 	}
3792 
3793 	list_for_each_entry(prange, &remap_list, update_list) {
3794 		pr_debug("Remapping prange 0x%p [0x%lx 0x%lx]\n",
3795 			 prange, prange->start, prange->last);
3796 		mutex_lock(&prange->migrate_mutex);
3797 		r = svm_range_validate_and_map(mm,  prange->start, prange->last, prange,
3798 					       MAX_GPU_INSTANCE, true, true, prange->mapped_to_gpu);
3799 		if (r)
3800 			pr_debug("failed %d on remap svm range\n", r);
3801 		mutex_unlock(&prange->migrate_mutex);
3802 		if (r)
3803 			ret = r;
3804 	}
3805 
3806 	dynamic_svm_range_dump(svms);
3807 
3808 	mutex_unlock(&svms->lock);
3809 	mmap_read_unlock(mm);
3810 out:
3811 	mutex_unlock(&process_info->lock);
3812 
3813 	pr_debug("process pid %d svms 0x%p [0x%llx 0x%llx] done, r=%d\n",
3814 		 p->lead_thread->pid, &p->svms, start, start + size - 1, r);
3815 
3816 	return ret ? ret : r;
3817 }
3818 
3819 static int
3820 svm_range_get_attr(struct kfd_process *p, struct mm_struct *mm,
3821 		   uint64_t start, uint64_t size, uint32_t nattr,
3822 		   struct kfd_ioctl_svm_attribute *attrs)
3823 {
3824 	DECLARE_BITMAP(bitmap_access, MAX_GPU_INSTANCE);
3825 	DECLARE_BITMAP(bitmap_aip, MAX_GPU_INSTANCE);
3826 	bool get_preferred_loc = false;
3827 	bool get_prefetch_loc = false;
3828 	bool get_granularity = false;
3829 	bool get_accessible = false;
3830 	bool get_flags = false;
3831 	uint64_t last = start + size - 1UL;
3832 	uint8_t granularity = 0xff;
3833 	struct interval_tree_node *node;
3834 	struct svm_range_list *svms;
3835 	struct svm_range *prange;
3836 	uint32_t prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3837 	uint32_t location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3838 	uint32_t flags_and = 0xffffffff;
3839 	uint32_t flags_or = 0;
3840 	int gpuidx;
3841 	uint32_t i;
3842 	int r = 0;
3843 
3844 	pr_debug("svms 0x%p [0x%llx 0x%llx] nattr 0x%x\n", &p->svms, start,
3845 		 start + size - 1, nattr);
3846 
3847 	/* Flush pending deferred work to avoid racing with deferred actions from
3848 	 * previous memory map changes (e.g. munmap). Concurrent memory map changes
3849 	 * can still race with get_attr because we don't hold the mmap lock. But that
3850 	 * would be a race condition in the application anyway, and undefined
3851 	 * behaviour is acceptable in that case.
3852 	 */
3853 	flush_work(&p->svms.deferred_list_work);
3854 
3855 	mmap_read_lock(mm);
3856 	r = svm_range_is_valid(p, start, size);
3857 	mmap_read_unlock(mm);
3858 	if (r) {
3859 		pr_debug("invalid range r=%d\n", r);
3860 		return r;
3861 	}
3862 
3863 	for (i = 0; i < nattr; i++) {
3864 		switch (attrs[i].type) {
3865 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3866 			get_preferred_loc = true;
3867 			break;
3868 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3869 			get_prefetch_loc = true;
3870 			break;
3871 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3872 			get_accessible = true;
3873 			break;
3874 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3875 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3876 			get_flags = true;
3877 			break;
3878 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3879 			get_granularity = true;
3880 			break;
3881 		case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE:
3882 		case KFD_IOCTL_SVM_ATTR_NO_ACCESS:
3883 			fallthrough;
3884 		default:
3885 			pr_debug("get invalid attr type 0x%x\n", attrs[i].type);
3886 			return -EINVAL;
3887 		}
3888 	}
3889 
3890 	svms = &p->svms;
3891 
3892 	mutex_lock(&svms->lock);
3893 
3894 	node = interval_tree_iter_first(&svms->objects, start, last);
3895 	if (!node) {
3896 		pr_debug("range attrs not found return default values\n");
3897 		svm_range_set_default_attributes(svms, &location, &prefetch_loc,
3898 						 &granularity, &flags_and);
3899 		flags_or = flags_and;
3900 		if (p->xnack_enabled)
3901 			bitmap_copy(bitmap_access, svms->bitmap_supported,
3902 				    MAX_GPU_INSTANCE);
3903 		else
3904 			bitmap_zero(bitmap_access, MAX_GPU_INSTANCE);
3905 		bitmap_zero(bitmap_aip, MAX_GPU_INSTANCE);
3906 		goto fill_values;
3907 	}
3908 	bitmap_copy(bitmap_access, svms->bitmap_supported, MAX_GPU_INSTANCE);
3909 	bitmap_copy(bitmap_aip, svms->bitmap_supported, MAX_GPU_INSTANCE);
3910 
3911 	while (node) {
3912 		struct interval_tree_node *next;
3913 
3914 		prange = container_of(node, struct svm_range, it_node);
3915 		next = interval_tree_iter_next(node, start, last);
3916 
3917 		if (get_preferred_loc) {
3918 			if (prange->preferred_loc ==
3919 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3920 			    (location != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3921 			     location != prange->preferred_loc)) {
3922 				location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3923 				get_preferred_loc = false;
3924 			} else {
3925 				location = prange->preferred_loc;
3926 			}
3927 		}
3928 		if (get_prefetch_loc) {
3929 			if (prange->prefetch_loc ==
3930 					KFD_IOCTL_SVM_LOCATION_UNDEFINED ||
3931 			    (prefetch_loc != KFD_IOCTL_SVM_LOCATION_UNDEFINED &&
3932 			     prefetch_loc != prange->prefetch_loc)) {
3933 				prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
3934 				get_prefetch_loc = false;
3935 			} else {
3936 				prefetch_loc = prange->prefetch_loc;
3937 			}
3938 		}
3939 		if (get_accessible) {
3940 			bitmap_and(bitmap_access, bitmap_access,
3941 				   prange->bitmap_access, MAX_GPU_INSTANCE);
3942 			bitmap_and(bitmap_aip, bitmap_aip,
3943 				   prange->bitmap_aip, MAX_GPU_INSTANCE);
3944 		}
3945 		if (get_flags) {
3946 			flags_and &= prange->flags;
3947 			flags_or |= prange->flags;
3948 		}
3949 
3950 		if (get_granularity && prange->granularity < granularity)
3951 			granularity = prange->granularity;
3952 
3953 		node = next;
3954 	}
3955 fill_values:
3956 	mutex_unlock(&svms->lock);
3957 
3958 	for (i = 0; i < nattr; i++) {
3959 		switch (attrs[i].type) {
3960 		case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC:
3961 			attrs[i].value = location;
3962 			break;
3963 		case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
3964 			attrs[i].value = prefetch_loc;
3965 			break;
3966 		case KFD_IOCTL_SVM_ATTR_ACCESS:
3967 			gpuidx = kfd_process_gpuidx_from_gpuid(p,
3968 							       attrs[i].value);
3969 			if (gpuidx < 0) {
3970 				pr_debug("invalid gpuid %x\n", attrs[i].value);
3971 				return -EINVAL;
3972 			}
3973 			if (test_bit(gpuidx, bitmap_access))
3974 				attrs[i].type = KFD_IOCTL_SVM_ATTR_ACCESS;
3975 			else if (test_bit(gpuidx, bitmap_aip))
3976 				attrs[i].type =
3977 					KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE;
3978 			else
3979 				attrs[i].type = KFD_IOCTL_SVM_ATTR_NO_ACCESS;
3980 			break;
3981 		case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
3982 			attrs[i].value = flags_and;
3983 			break;
3984 		case KFD_IOCTL_SVM_ATTR_CLR_FLAGS:
3985 			attrs[i].value = ~flags_or;
3986 			break;
3987 		case KFD_IOCTL_SVM_ATTR_GRANULARITY:
3988 			attrs[i].value = (uint32_t)granularity;
3989 			break;
3990 		}
3991 	}
3992 
3993 	return 0;
3994 }
3995 
3996 int kfd_criu_resume_svm(struct kfd_process *p)
3997 {
3998 	struct kfd_ioctl_svm_attribute *set_attr_new, *set_attr = NULL;
3999 	int nattr_common = 4, nattr_accessibility = 1;
4000 	struct criu_svm_metadata *criu_svm_md = NULL;
4001 	struct svm_range_list *svms = &p->svms;
4002 	struct criu_svm_metadata *next = NULL;
4003 	uint32_t set_flags = 0xffffffff;
4004 	int i, j, num_attrs, ret = 0;
4005 	uint64_t set_attr_size;
4006 	struct mm_struct *mm;
4007 
4008 	if (list_empty(&svms->criu_svm_metadata_list)) {
4009 		pr_debug("No SVM data from CRIU restore stage 2\n");
4010 		return ret;
4011 	}
4012 
4013 	mm = get_task_mm(p->lead_thread);
4014 	if (!mm) {
4015 		pr_err("failed to get mm for the target process\n");
4016 		return -ESRCH;
4017 	}
4018 
4019 	num_attrs = nattr_common + (nattr_accessibility * p->n_pdds);
4020 
4021 	i = j = 0;
4022 	list_for_each_entry(criu_svm_md, &svms->criu_svm_metadata_list, list) {
4023 		pr_debug("criu_svm_md[%d]\n\tstart: 0x%llx size: 0x%llx (npages)\n",
4024 			 i, criu_svm_md->data.start_addr, criu_svm_md->data.size);
4025 
4026 		for (j = 0; j < num_attrs; j++) {
4027 			pr_debug("\ncriu_svm_md[%d]->attrs[%d].type : 0x%x\ncriu_svm_md[%d]->attrs[%d].value : 0x%x\n",
4028 				 i, j, criu_svm_md->data.attrs[j].type,
4029 				 i, j, criu_svm_md->data.attrs[j].value);
4030 			switch (criu_svm_md->data.attrs[j].type) {
4031 			/* During Checkpoint operation, the query for
4032 			 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC attribute might
4033 			 * return KFD_IOCTL_SVM_LOCATION_UNDEFINED if they were
4034 			 * not used by the range which was checkpointed. Care
4035 			 * must be taken to not restore with an invalid value
4036 			 * otherwise the gpuidx value will be invalid and
4037 			 * set_attr would eventually fail so just replace those
4038 			 * with another dummy attribute such as
4039 			 * KFD_IOCTL_SVM_ATTR_SET_FLAGS.
4040 			 */
4041 			case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC:
4042 				if (criu_svm_md->data.attrs[j].value ==
4043 				    KFD_IOCTL_SVM_LOCATION_UNDEFINED) {
4044 					criu_svm_md->data.attrs[j].type =
4045 						KFD_IOCTL_SVM_ATTR_SET_FLAGS;
4046 					criu_svm_md->data.attrs[j].value = 0;
4047 				}
4048 				break;
4049 			case KFD_IOCTL_SVM_ATTR_SET_FLAGS:
4050 				set_flags = criu_svm_md->data.attrs[j].value;
4051 				break;
4052 			default:
4053 				break;
4054 			}
4055 		}
4056 
4057 		/* CLR_FLAGS is not available via get_attr during checkpoint but
4058 		 * it needs to be inserted before restoring the ranges so
4059 		 * allocate extra space for it before calling set_attr
4060 		 */
4061 		set_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4062 						(num_attrs + 1);
4063 		set_attr_new = krealloc(set_attr, set_attr_size,
4064 					    GFP_KERNEL);
4065 		if (!set_attr_new) {
4066 			ret = -ENOMEM;
4067 			goto exit;
4068 		}
4069 		set_attr = set_attr_new;
4070 
4071 		memcpy(set_attr, criu_svm_md->data.attrs, num_attrs *
4072 					sizeof(struct kfd_ioctl_svm_attribute));
4073 		set_attr[num_attrs].type = KFD_IOCTL_SVM_ATTR_CLR_FLAGS;
4074 		set_attr[num_attrs].value = ~set_flags;
4075 
4076 		ret = svm_range_set_attr(p, mm, criu_svm_md->data.start_addr,
4077 					 criu_svm_md->data.size, num_attrs + 1,
4078 					 set_attr);
4079 		if (ret) {
4080 			pr_err("CRIU: failed to set range attributes\n");
4081 			goto exit;
4082 		}
4083 
4084 		i++;
4085 	}
4086 exit:
4087 	kfree(set_attr);
4088 	list_for_each_entry_safe(criu_svm_md, next, &svms->criu_svm_metadata_list, list) {
4089 		pr_debug("freeing criu_svm_md[]\n\tstart: 0x%llx\n",
4090 						criu_svm_md->data.start_addr);
4091 		kfree(criu_svm_md);
4092 	}
4093 
4094 	mmput(mm);
4095 	return ret;
4096 
4097 }
4098 
4099 int kfd_criu_restore_svm(struct kfd_process *p,
4100 			 uint8_t __user *user_priv_ptr,
4101 			 uint64_t *priv_data_offset,
4102 			 uint64_t max_priv_data_size)
4103 {
4104 	uint64_t svm_priv_data_size, svm_object_md_size, svm_attrs_size;
4105 	int nattr_common = 4, nattr_accessibility = 1;
4106 	struct criu_svm_metadata *criu_svm_md = NULL;
4107 	struct svm_range_list *svms = &p->svms;
4108 	uint32_t num_devices;
4109 	int ret = 0;
4110 
4111 	num_devices = p->n_pdds;
4112 	/* Handle one SVM range object at a time, also the number of gpus are
4113 	 * assumed to be same on the restore node, checking must be done while
4114 	 * evaluating the topology earlier
4115 	 */
4116 
4117 	svm_attrs_size = sizeof(struct kfd_ioctl_svm_attribute) *
4118 		(nattr_common + nattr_accessibility * num_devices);
4119 	svm_object_md_size = sizeof(struct criu_svm_metadata) + svm_attrs_size;
4120 
4121 	svm_priv_data_size = sizeof(struct kfd_criu_svm_range_priv_data) +
4122 								svm_attrs_size;
4123 
4124 	criu_svm_md = kzalloc(svm_object_md_size, GFP_KERNEL);
4125 	if (!criu_svm_md) {
4126 		pr_err("failed to allocate memory to store svm metadata\n");
4127 		return -ENOMEM;
4128 	}
4129 	if (*priv_data_offset + svm_priv_data_size > max_priv_data_size) {
4130 		ret = -EINVAL;
4131 		goto exit;
4132 	}
4133 
4134 	ret = copy_from_user(&criu_svm_md->data, user_priv_ptr + *priv_data_offset,
4135 			     svm_priv_data_size);
4136 	if (ret) {
4137 		ret = -EFAULT;
4138 		goto exit;
4139 	}
4140 	*priv_data_offset += svm_priv_data_size;
4141 
4142 	list_add_tail(&criu_svm_md->list, &svms->criu_svm_metadata_list);
4143 
4144 	return 0;
4145 
4146 
4147 exit:
4148 	kfree(criu_svm_md);
4149 	return ret;
4150 }
4151 
4152 void svm_range_get_info(struct kfd_process *p, uint32_t *num_svm_ranges,
4153 			uint64_t *svm_priv_data_size)
4154 {
4155 	uint64_t total_size, accessibility_size, common_attr_size;
4156 	int nattr_common = 4, nattr_accessibility = 1;
4157 	int num_devices = p->n_pdds;
4158 	struct svm_range_list *svms;
4159 	struct svm_range *prange;
4160 	uint32_t count = 0;
4161 
4162 	*svm_priv_data_size = 0;
4163 
4164 	svms = &p->svms;
4165 
4166 	mutex_lock(&svms->lock);
4167 	list_for_each_entry(prange, &svms->list, list) {
4168 		pr_debug("prange: 0x%p start: 0x%lx\t npages: 0x%llx\t end: 0x%llx\n",
4169 			 prange, prange->start, prange->npages,
4170 			 prange->start + prange->npages - 1);
4171 		count++;
4172 	}
4173 	mutex_unlock(&svms->lock);
4174 
4175 	*num_svm_ranges = count;
4176 	/* Only the accessbility attributes need to be queried for all the gpus
4177 	 * individually, remaining ones are spanned across the entire process
4178 	 * regardless of the various gpu nodes. Of the remaining attributes,
4179 	 * KFD_IOCTL_SVM_ATTR_CLR_FLAGS need not be saved.
4180 	 *
4181 	 * KFD_IOCTL_SVM_ATTR_PREFERRED_LOC
4182 	 * KFD_IOCTL_SVM_ATTR_PREFETCH_LOC
4183 	 * KFD_IOCTL_SVM_ATTR_SET_FLAGS
4184 	 * KFD_IOCTL_SVM_ATTR_GRANULARITY
4185 	 *
4186 	 * ** ACCESSBILITY ATTRIBUTES **
4187 	 * (Considered as one, type is altered during query, value is gpuid)
4188 	 * KFD_IOCTL_SVM_ATTR_ACCESS
4189 	 * KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE
4190 	 * KFD_IOCTL_SVM_ATTR_NO_ACCESS
4191 	 */
4192 	if (*num_svm_ranges > 0) {
4193 		common_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4194 			nattr_common;
4195 		accessibility_size = sizeof(struct kfd_ioctl_svm_attribute) *
4196 			nattr_accessibility * num_devices;
4197 
4198 		total_size = sizeof(struct kfd_criu_svm_range_priv_data) +
4199 			common_attr_size + accessibility_size;
4200 
4201 		*svm_priv_data_size = *num_svm_ranges * total_size;
4202 	}
4203 
4204 	pr_debug("num_svm_ranges %u total_priv_size %llu\n", *num_svm_ranges,
4205 		 *svm_priv_data_size);
4206 }
4207 
4208 int kfd_criu_checkpoint_svm(struct kfd_process *p,
4209 			    uint8_t __user *user_priv_data,
4210 			    uint64_t *priv_data_offset)
4211 {
4212 	struct kfd_criu_svm_range_priv_data *svm_priv = NULL;
4213 	struct kfd_ioctl_svm_attribute *query_attr = NULL;
4214 	uint64_t svm_priv_data_size, query_attr_size = 0;
4215 	int index, nattr_common = 4, ret = 0;
4216 	struct svm_range_list *svms;
4217 	int num_devices = p->n_pdds;
4218 	struct svm_range *prange;
4219 	struct mm_struct *mm;
4220 
4221 	svms = &p->svms;
4222 
4223 	mm = get_task_mm(p->lead_thread);
4224 	if (!mm) {
4225 		pr_err("failed to get mm for the target process\n");
4226 		return -ESRCH;
4227 	}
4228 
4229 	query_attr_size = sizeof(struct kfd_ioctl_svm_attribute) *
4230 				(nattr_common + num_devices);
4231 
4232 	query_attr = kzalloc(query_attr_size, GFP_KERNEL);
4233 	if (!query_attr) {
4234 		ret = -ENOMEM;
4235 		goto exit;
4236 	}
4237 
4238 	query_attr[0].type = KFD_IOCTL_SVM_ATTR_PREFERRED_LOC;
4239 	query_attr[1].type = KFD_IOCTL_SVM_ATTR_PREFETCH_LOC;
4240 	query_attr[2].type = KFD_IOCTL_SVM_ATTR_SET_FLAGS;
4241 	query_attr[3].type = KFD_IOCTL_SVM_ATTR_GRANULARITY;
4242 
4243 	for (index = 0; index < num_devices; index++) {
4244 		struct kfd_process_device *pdd = p->pdds[index];
4245 
4246 		query_attr[index + nattr_common].type =
4247 			KFD_IOCTL_SVM_ATTR_ACCESS;
4248 		query_attr[index + nattr_common].value = pdd->user_gpu_id;
4249 	}
4250 
4251 	svm_priv_data_size = sizeof(*svm_priv) + query_attr_size;
4252 
4253 	svm_priv = kzalloc(svm_priv_data_size, GFP_KERNEL);
4254 	if (!svm_priv) {
4255 		ret = -ENOMEM;
4256 		goto exit_query;
4257 	}
4258 
4259 	index = 0;
4260 	list_for_each_entry(prange, &svms->list, list) {
4261 
4262 		svm_priv->object_type = KFD_CRIU_OBJECT_TYPE_SVM_RANGE;
4263 		svm_priv->start_addr = prange->start;
4264 		svm_priv->size = prange->npages;
4265 		memcpy(&svm_priv->attrs, query_attr, query_attr_size);
4266 		pr_debug("CRIU: prange: 0x%p start: 0x%lx\t npages: 0x%llx end: 0x%llx\t size: 0x%llx\n",
4267 			 prange, prange->start, prange->npages,
4268 			 prange->start + prange->npages - 1,
4269 			 prange->npages * PAGE_SIZE);
4270 
4271 		ret = svm_range_get_attr(p, mm, svm_priv->start_addr,
4272 					 svm_priv->size,
4273 					 (nattr_common + num_devices),
4274 					 svm_priv->attrs);
4275 		if (ret) {
4276 			pr_err("CRIU: failed to obtain range attributes\n");
4277 			goto exit_priv;
4278 		}
4279 
4280 		if (copy_to_user(user_priv_data + *priv_data_offset, svm_priv,
4281 				 svm_priv_data_size)) {
4282 			pr_err("Failed to copy svm priv to user\n");
4283 			ret = -EFAULT;
4284 			goto exit_priv;
4285 		}
4286 
4287 		*priv_data_offset += svm_priv_data_size;
4288 
4289 	}
4290 
4291 
4292 exit_priv:
4293 	kfree(svm_priv);
4294 exit_query:
4295 	kfree(query_attr);
4296 exit:
4297 	mmput(mm);
4298 	return ret;
4299 }
4300 
4301 int
4302 svm_ioctl(struct kfd_process *p, enum kfd_ioctl_svm_op op, uint64_t start,
4303 	  uint64_t size, uint32_t nattrs, struct kfd_ioctl_svm_attribute *attrs)
4304 {
4305 	struct mm_struct *mm = current->mm;
4306 	int r;
4307 
4308 	start >>= PAGE_SHIFT;
4309 	size >>= PAGE_SHIFT;
4310 
4311 	switch (op) {
4312 	case KFD_IOCTL_SVM_OP_SET_ATTR:
4313 		r = svm_range_set_attr(p, mm, start, size, nattrs, attrs);
4314 		break;
4315 	case KFD_IOCTL_SVM_OP_GET_ATTR:
4316 		r = svm_range_get_attr(p, mm, start, size, nattrs, attrs);
4317 		break;
4318 	default:
4319 		r = -EINVAL;
4320 		break;
4321 	}
4322 
4323 	return r;
4324 }
4325