xref: /linux/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c (revision 2c1ed907520c50326b8f604907a8478b27881a2e)
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 #include <linux/types.h>
24 #include <linux/hmm.h>
25 #include <linux/dma-direction.h>
26 #include <linux/dma-mapping.h>
27 #include <linux/migrate.h>
28 #include "amdgpu_sync.h"
29 #include "amdgpu_object.h"
30 #include "amdgpu_vm.h"
31 #include "amdgpu_res_cursor.h"
32 #include "kfd_priv.h"
33 #include "kfd_svm.h"
34 #include "kfd_migrate.h"
35 #include "kfd_smi_events.h"
36 
37 #ifdef dev_fmt
38 #undef dev_fmt
39 #endif
40 #define dev_fmt(fmt) "kfd_migrate: " fmt
41 
42 static uint64_t
svm_migrate_direct_mapping_addr(struct amdgpu_device * adev,uint64_t addr)43 svm_migrate_direct_mapping_addr(struct amdgpu_device *adev, uint64_t addr)
44 {
45 	return addr + amdgpu_ttm_domain_start(adev, TTM_PL_VRAM);
46 }
47 
48 static int
svm_migrate_gart_map(struct amdgpu_ring * ring,uint64_t npages,dma_addr_t * addr,uint64_t * gart_addr,uint64_t flags)49 svm_migrate_gart_map(struct amdgpu_ring *ring, uint64_t npages,
50 		     dma_addr_t *addr, uint64_t *gart_addr, uint64_t flags)
51 {
52 	struct amdgpu_device *adev = ring->adev;
53 	struct amdgpu_job *job;
54 	unsigned int num_dw, num_bytes;
55 	struct dma_fence *fence;
56 	uint64_t src_addr, dst_addr;
57 	uint64_t pte_flags;
58 	void *cpu_addr;
59 	int r;
60 
61 	/* use gart window 0 */
62 	*gart_addr = adev->gmc.gart_start;
63 
64 	num_dw = ALIGN(adev->mman.buffer_funcs->copy_num_dw, 8);
65 	num_bytes = npages * 8;
66 
67 	r = amdgpu_job_alloc_with_ib(adev, &adev->mman.high_pr,
68 				     AMDGPU_FENCE_OWNER_UNDEFINED,
69 				     num_dw * 4 + num_bytes,
70 				     AMDGPU_IB_POOL_DELAYED,
71 				     &job);
72 	if (r)
73 		return r;
74 
75 	src_addr = num_dw * 4;
76 	src_addr += job->ibs[0].gpu_addr;
77 
78 	dst_addr = amdgpu_bo_gpu_offset(adev->gart.bo);
79 	amdgpu_emit_copy_buffer(adev, &job->ibs[0], src_addr,
80 				dst_addr, num_bytes, 0);
81 
82 	amdgpu_ring_pad_ib(ring, &job->ibs[0]);
83 	WARN_ON(job->ibs[0].length_dw > num_dw);
84 
85 	pte_flags = AMDGPU_PTE_VALID | AMDGPU_PTE_READABLE;
86 	pte_flags |= AMDGPU_PTE_SYSTEM | AMDGPU_PTE_SNOOPED;
87 	if (!(flags & KFD_IOCTL_SVM_FLAG_GPU_RO))
88 		pte_flags |= AMDGPU_PTE_WRITEABLE;
89 	pte_flags |= adev->gart.gart_pte_flags;
90 
91 	cpu_addr = &job->ibs[0].ptr[num_dw];
92 
93 	amdgpu_gart_map(adev, 0, npages, addr, pte_flags, cpu_addr);
94 	fence = amdgpu_job_submit(job);
95 	dma_fence_put(fence);
96 
97 	return r;
98 }
99 
100 /**
101  * svm_migrate_copy_memory_gart - sdma copy data between ram and vram
102  *
103  * @adev: amdgpu device the sdma ring running
104  * @sys: system DMA pointer to be copied
105  * @vram: vram destination DMA pointer
106  * @npages: number of pages to copy
107  * @direction: enum MIGRATION_COPY_DIR
108  * @mfence: output, sdma fence to signal after sdma is done
109  *
110  * ram address uses GART table continuous entries mapping to ram pages,
111  * vram address uses direct mapping of vram pages, which must have npages
112  * number of continuous pages.
113  * GART update and sdma uses same buf copy function ring, sdma is splited to
114  * multiple GTT_MAX_PAGES transfer, all sdma operations are serialized, wait for
115  * the last sdma finish fence which is returned to check copy memory is done.
116  *
117  * Context: Process context, takes and releases gtt_window_lock
118  *
119  * Return:
120  * 0 - OK, otherwise error code
121  */
122 
123 static int
svm_migrate_copy_memory_gart(struct amdgpu_device * adev,dma_addr_t * sys,uint64_t * vram,uint64_t npages,enum MIGRATION_COPY_DIR direction,struct dma_fence ** mfence)124 svm_migrate_copy_memory_gart(struct amdgpu_device *adev, dma_addr_t *sys,
125 			     uint64_t *vram, uint64_t npages,
126 			     enum MIGRATION_COPY_DIR direction,
127 			     struct dma_fence **mfence)
128 {
129 	const uint64_t GTT_MAX_PAGES = AMDGPU_GTT_MAX_TRANSFER_SIZE;
130 	struct amdgpu_ring *ring = adev->mman.buffer_funcs_ring;
131 	uint64_t gart_s, gart_d;
132 	struct dma_fence *next;
133 	uint64_t size;
134 	int r;
135 
136 	mutex_lock(&adev->mman.gtt_window_lock);
137 
138 	while (npages) {
139 		size = min(GTT_MAX_PAGES, npages);
140 
141 		if (direction == FROM_VRAM_TO_RAM) {
142 			gart_s = svm_migrate_direct_mapping_addr(adev, *vram);
143 			r = svm_migrate_gart_map(ring, size, sys, &gart_d, 0);
144 
145 		} else if (direction == FROM_RAM_TO_VRAM) {
146 			r = svm_migrate_gart_map(ring, size, sys, &gart_s,
147 						 KFD_IOCTL_SVM_FLAG_GPU_RO);
148 			gart_d = svm_migrate_direct_mapping_addr(adev, *vram);
149 		}
150 		if (r) {
151 			dev_err(adev->dev, "fail %d create gart mapping\n", r);
152 			goto out_unlock;
153 		}
154 
155 		r = amdgpu_copy_buffer(ring, gart_s, gart_d, size * PAGE_SIZE,
156 				       NULL, &next, false, true, 0);
157 		if (r) {
158 			dev_err(adev->dev, "fail %d to copy memory\n", r);
159 			goto out_unlock;
160 		}
161 
162 		dma_fence_put(*mfence);
163 		*mfence = next;
164 		npages -= size;
165 		if (npages) {
166 			sys += size;
167 			vram += size;
168 		}
169 	}
170 
171 out_unlock:
172 	mutex_unlock(&adev->mman.gtt_window_lock);
173 
174 	return r;
175 }
176 
177 /**
178  * svm_migrate_copy_done - wait for memory copy sdma is done
179  *
180  * @adev: amdgpu device the sdma memory copy is executing on
181  * @mfence: migrate fence
182  *
183  * Wait for dma fence is signaled, if the copy ssplit into multiple sdma
184  * operations, this is the last sdma operation fence.
185  *
186  * Context: called after svm_migrate_copy_memory
187  *
188  * Return:
189  * 0		- success
190  * otherwise	- error code from dma fence signal
191  */
192 static int
svm_migrate_copy_done(struct amdgpu_device * adev,struct dma_fence * mfence)193 svm_migrate_copy_done(struct amdgpu_device *adev, struct dma_fence *mfence)
194 {
195 	int r = 0;
196 
197 	if (mfence) {
198 		r = dma_fence_wait(mfence, false);
199 		dma_fence_put(mfence);
200 		pr_debug("sdma copy memory fence done\n");
201 	}
202 
203 	return r;
204 }
205 
206 unsigned long
svm_migrate_addr_to_pfn(struct amdgpu_device * adev,unsigned long addr)207 svm_migrate_addr_to_pfn(struct amdgpu_device *adev, unsigned long addr)
208 {
209 	return (addr + adev->kfd.pgmap.range.start) >> PAGE_SHIFT;
210 }
211 
212 static void
svm_migrate_get_vram_page(struct svm_range * prange,unsigned long pfn)213 svm_migrate_get_vram_page(struct svm_range *prange, unsigned long pfn)
214 {
215 	struct page *page;
216 
217 	page = pfn_to_page(pfn);
218 	svm_range_bo_ref(prange->svm_bo);
219 	page->zone_device_data = prange->svm_bo;
220 	zone_device_page_init(page);
221 }
222 
223 static void
svm_migrate_put_vram_page(struct amdgpu_device * adev,unsigned long addr)224 svm_migrate_put_vram_page(struct amdgpu_device *adev, unsigned long addr)
225 {
226 	struct page *page;
227 
228 	page = pfn_to_page(svm_migrate_addr_to_pfn(adev, addr));
229 	unlock_page(page);
230 	put_page(page);
231 }
232 
233 static unsigned long
svm_migrate_addr(struct amdgpu_device * adev,struct page * page)234 svm_migrate_addr(struct amdgpu_device *adev, struct page *page)
235 {
236 	unsigned long addr;
237 
238 	addr = page_to_pfn(page) << PAGE_SHIFT;
239 	return (addr - adev->kfd.pgmap.range.start);
240 }
241 
242 static struct page *
svm_migrate_get_sys_page(struct vm_area_struct * vma,unsigned long addr)243 svm_migrate_get_sys_page(struct vm_area_struct *vma, unsigned long addr)
244 {
245 	struct page *page;
246 
247 	page = alloc_page_vma(GFP_HIGHUSER, vma, addr);
248 	if (page)
249 		lock_page(page);
250 
251 	return page;
252 }
253 
svm_migrate_put_sys_page(unsigned long addr)254 static void svm_migrate_put_sys_page(unsigned long addr)
255 {
256 	struct page *page;
257 
258 	page = pfn_to_page(addr >> PAGE_SHIFT);
259 	unlock_page(page);
260 	put_page(page);
261 }
262 
svm_migrate_unsuccessful_pages(struct migrate_vma * migrate)263 static unsigned long svm_migrate_unsuccessful_pages(struct migrate_vma *migrate)
264 {
265 	unsigned long upages = 0;
266 	unsigned long i;
267 
268 	for (i = 0; i < migrate->npages; i++) {
269 		if (migrate->src[i] & MIGRATE_PFN_VALID &&
270 		    !(migrate->src[i] & MIGRATE_PFN_MIGRATE))
271 			upages++;
272 	}
273 	return upages;
274 }
275 
276 static int
svm_migrate_copy_to_vram(struct kfd_node * node,struct svm_range * prange,struct migrate_vma * migrate,struct dma_fence ** mfence,dma_addr_t * scratch,uint64_t ttm_res_offset)277 svm_migrate_copy_to_vram(struct kfd_node *node, struct svm_range *prange,
278 			 struct migrate_vma *migrate, struct dma_fence **mfence,
279 			 dma_addr_t *scratch, uint64_t ttm_res_offset)
280 {
281 	uint64_t npages = migrate->npages;
282 	struct amdgpu_device *adev = node->adev;
283 	struct device *dev = adev->dev;
284 	struct amdgpu_res_cursor cursor;
285 	uint64_t mpages = 0;
286 	dma_addr_t *src;
287 	uint64_t *dst;
288 	uint64_t i, j;
289 	int r;
290 
291 	pr_debug("svms 0x%p [0x%lx 0x%lx 0x%llx]\n", prange->svms, prange->start,
292 		 prange->last, ttm_res_offset);
293 
294 	src = scratch;
295 	dst = (uint64_t *)(scratch + npages);
296 
297 	amdgpu_res_first(prange->ttm_res, ttm_res_offset,
298 			 npages << PAGE_SHIFT, &cursor);
299 	for (i = j = 0; (i < npages) && (mpages < migrate->cpages); i++) {
300 		struct page *spage;
301 
302 		if (migrate->src[i] & MIGRATE_PFN_MIGRATE) {
303 			dst[i] = cursor.start + (j << PAGE_SHIFT);
304 			migrate->dst[i] = svm_migrate_addr_to_pfn(adev, dst[i]);
305 			svm_migrate_get_vram_page(prange, migrate->dst[i]);
306 			migrate->dst[i] = migrate_pfn(migrate->dst[i]);
307 			mpages++;
308 		}
309 		spage = migrate_pfn_to_page(migrate->src[i]);
310 		if (spage && !is_zone_device_page(spage)) {
311 			src[i] = dma_map_page(dev, spage, 0, PAGE_SIZE,
312 					      DMA_BIDIRECTIONAL);
313 			r = dma_mapping_error(dev, src[i]);
314 			if (r) {
315 				dev_err(dev, "%s: fail %d dma_map_page\n",
316 					__func__, r);
317 				goto out_free_vram_pages;
318 			}
319 		} else {
320 			if (j) {
321 				r = svm_migrate_copy_memory_gart(
322 						adev, src + i - j,
323 						dst + i - j, j,
324 						FROM_RAM_TO_VRAM,
325 						mfence);
326 				if (r)
327 					goto out_free_vram_pages;
328 				amdgpu_res_next(&cursor, (j + 1) << PAGE_SHIFT);
329 				j = 0;
330 			} else {
331 				amdgpu_res_next(&cursor, PAGE_SIZE);
332 			}
333 			continue;
334 		}
335 
336 		pr_debug_ratelimited("dma mapping src to 0x%llx, pfn 0x%lx\n",
337 				     src[i] >> PAGE_SHIFT, page_to_pfn(spage));
338 
339 		if (j >= (cursor.size >> PAGE_SHIFT) - 1 && i < npages - 1) {
340 			r = svm_migrate_copy_memory_gart(adev, src + i - j,
341 							 dst + i - j, j + 1,
342 							 FROM_RAM_TO_VRAM,
343 							 mfence);
344 			if (r)
345 				goto out_free_vram_pages;
346 			amdgpu_res_next(&cursor, (j + 1) * PAGE_SIZE);
347 			j = 0;
348 		} else {
349 			j++;
350 		}
351 	}
352 
353 	r = svm_migrate_copy_memory_gart(adev, src + i - j, dst + i - j, j,
354 					 FROM_RAM_TO_VRAM, mfence);
355 
356 out_free_vram_pages:
357 	if (r) {
358 		pr_debug("failed %d to copy memory to vram\n", r);
359 		for (i = 0; i < npages && mpages; i++) {
360 			if (!dst[i])
361 				continue;
362 			svm_migrate_put_vram_page(adev, dst[i]);
363 			migrate->dst[i] = 0;
364 			mpages--;
365 		}
366 	}
367 
368 #ifdef DEBUG_FORCE_MIXED_DOMAINS
369 	for (i = 0, j = 0; i < npages; i += 4, j++) {
370 		if (j & 1)
371 			continue;
372 		svm_migrate_put_vram_page(adev, dst[i]);
373 		migrate->dst[i] = 0;
374 		svm_migrate_put_vram_page(adev, dst[i + 1]);
375 		migrate->dst[i + 1] = 0;
376 		svm_migrate_put_vram_page(adev, dst[i + 2]);
377 		migrate->dst[i + 2] = 0;
378 		svm_migrate_put_vram_page(adev, dst[i + 3]);
379 		migrate->dst[i + 3] = 0;
380 	}
381 #endif
382 
383 	return r;
384 }
385 
386 static long
svm_migrate_vma_to_vram(struct kfd_node * node,struct svm_range * prange,struct vm_area_struct * vma,uint64_t start,uint64_t end,uint32_t trigger,uint64_t ttm_res_offset)387 svm_migrate_vma_to_vram(struct kfd_node *node, struct svm_range *prange,
388 			struct vm_area_struct *vma, uint64_t start,
389 			uint64_t end, uint32_t trigger, uint64_t ttm_res_offset)
390 {
391 	struct kfd_process *p = container_of(prange->svms, struct kfd_process, svms);
392 	uint64_t npages = (end - start) >> PAGE_SHIFT;
393 	struct amdgpu_device *adev = node->adev;
394 	struct kfd_process_device *pdd;
395 	struct dma_fence *mfence = NULL;
396 	struct migrate_vma migrate = { 0 };
397 	unsigned long cpages = 0;
398 	unsigned long mpages = 0;
399 	dma_addr_t *scratch;
400 	void *buf;
401 	int r = -ENOMEM;
402 
403 	memset(&migrate, 0, sizeof(migrate));
404 	migrate.vma = vma;
405 	migrate.start = start;
406 	migrate.end = end;
407 	migrate.flags = MIGRATE_VMA_SELECT_SYSTEM;
408 	migrate.pgmap_owner = SVM_ADEV_PGMAP_OWNER(adev);
409 
410 	buf = kvcalloc(npages,
411 		       2 * sizeof(*migrate.src) + sizeof(uint64_t) + sizeof(dma_addr_t),
412 		       GFP_KERNEL);
413 	if (!buf)
414 		goto out;
415 
416 	migrate.src = buf;
417 	migrate.dst = migrate.src + npages;
418 	scratch = (dma_addr_t *)(migrate.dst + npages);
419 
420 	kfd_smi_event_migration_start(node, p->lead_thread->pid,
421 				      start >> PAGE_SHIFT, end >> PAGE_SHIFT,
422 				      0, node->id, prange->prefetch_loc,
423 				      prange->preferred_loc, trigger);
424 
425 	r = migrate_vma_setup(&migrate);
426 	if (r) {
427 		dev_err(adev->dev, "%s: vma setup fail %d range [0x%lx 0x%lx]\n",
428 			__func__, r, prange->start, prange->last);
429 		goto out_free;
430 	}
431 
432 	cpages = migrate.cpages;
433 	if (!cpages) {
434 		pr_debug("failed collect migrate sys pages [0x%lx 0x%lx]\n",
435 			 prange->start, prange->last);
436 		goto out_free;
437 	}
438 	if (cpages != npages)
439 		pr_debug("partial migration, 0x%lx/0x%llx pages collected\n",
440 			 cpages, npages);
441 	else
442 		pr_debug("0x%lx pages collected\n", cpages);
443 
444 	r = svm_migrate_copy_to_vram(node, prange, &migrate, &mfence, scratch, ttm_res_offset);
445 	migrate_vma_pages(&migrate);
446 
447 	svm_migrate_copy_done(adev, mfence);
448 	migrate_vma_finalize(&migrate);
449 
450 	mpages = cpages - svm_migrate_unsuccessful_pages(&migrate);
451 	pr_debug("successful/cpages/npages 0x%lx/0x%lx/0x%lx\n",
452 			 mpages, cpages, migrate.npages);
453 
454 	svm_range_dma_unmap_dev(adev->dev, scratch, 0, npages);
455 
456 out_free:
457 	kvfree(buf);
458 	kfd_smi_event_migration_end(node, p->lead_thread->pid,
459 				    start >> PAGE_SHIFT, end >> PAGE_SHIFT,
460 				    0, node->id, trigger, r);
461 out:
462 	if (!r && mpages) {
463 		pdd = svm_range_get_pdd_by_node(prange, node);
464 		if (pdd)
465 			WRITE_ONCE(pdd->page_in, pdd->page_in + mpages);
466 
467 		return mpages;
468 	}
469 	return r;
470 }
471 
472 /**
473  * svm_migrate_ram_to_vram - migrate svm range from system to device
474  * @prange: range structure
475  * @best_loc: the device to migrate to
476  * @start_mgr: start page to migrate
477  * @last_mgr: last page to migrate
478  * @mm: the process mm structure
479  * @trigger: reason of migration
480  *
481  * Context: Process context, caller hold mmap read lock, svms lock, prange lock
482  *
483  * Return:
484  * 0 - OK, otherwise error code
485  */
486 static int
svm_migrate_ram_to_vram(struct svm_range * prange,uint32_t best_loc,unsigned long start_mgr,unsigned long last_mgr,struct mm_struct * mm,uint32_t trigger)487 svm_migrate_ram_to_vram(struct svm_range *prange, uint32_t best_loc,
488 			unsigned long start_mgr, unsigned long last_mgr,
489 			struct mm_struct *mm, uint32_t trigger)
490 {
491 	unsigned long addr, start, end;
492 	struct vm_area_struct *vma;
493 	uint64_t ttm_res_offset;
494 	struct kfd_node *node;
495 	unsigned long mpages = 0;
496 	long r = 0;
497 
498 	if (start_mgr < prange->start || last_mgr > prange->last) {
499 		pr_debug("range [0x%lx 0x%lx] out prange [0x%lx 0x%lx]\n",
500 			 start_mgr, last_mgr, prange->start, prange->last);
501 		return -EFAULT;
502 	}
503 
504 	node = svm_range_get_node_by_id(prange, best_loc);
505 	if (!node) {
506 		pr_debug("failed to get kfd node by id 0x%x\n", best_loc);
507 		return -ENODEV;
508 	}
509 
510 	pr_debug("svms 0x%p [0x%lx 0x%lx] in [0x%lx 0x%lx] to gpu 0x%x\n",
511 		prange->svms, start_mgr, last_mgr, prange->start, prange->last,
512 		best_loc);
513 
514 	start = start_mgr << PAGE_SHIFT;
515 	end = (last_mgr + 1) << PAGE_SHIFT;
516 
517 	r = amdgpu_amdkfd_reserve_mem_limit(node->adev,
518 					prange->npages * PAGE_SIZE,
519 					KFD_IOC_ALLOC_MEM_FLAGS_VRAM,
520 					node->xcp ? node->xcp->id : 0);
521 	if (r) {
522 		dev_dbg(node->adev->dev, "failed to reserve VRAM, r: %ld\n", r);
523 		return -ENOSPC;
524 	}
525 
526 	r = svm_range_vram_node_new(node, prange, true);
527 	if (r) {
528 		dev_dbg(node->adev->dev, "fail %ld to alloc vram\n", r);
529 		goto out;
530 	}
531 	ttm_res_offset = (start_mgr - prange->start + prange->offset) << PAGE_SHIFT;
532 
533 	for (addr = start; addr < end;) {
534 		unsigned long next;
535 
536 		vma = vma_lookup(mm, addr);
537 		if (!vma)
538 			break;
539 
540 		next = min(vma->vm_end, end);
541 		r = svm_migrate_vma_to_vram(node, prange, vma, addr, next, trigger, ttm_res_offset);
542 		if (r < 0) {
543 			pr_debug("failed %ld to migrate\n", r);
544 			break;
545 		} else {
546 			mpages += r;
547 		}
548 		ttm_res_offset += next - addr;
549 		addr = next;
550 	}
551 
552 	if (mpages) {
553 		prange->actual_loc = best_loc;
554 		prange->vram_pages += mpages;
555 	} else if (!prange->actual_loc) {
556 		/* if no page migrated and all pages from prange are at
557 		 * sys ram drop svm_bo got from svm_range_vram_node_new
558 		 */
559 		svm_range_vram_node_free(prange);
560 	}
561 
562 out:
563 	amdgpu_amdkfd_unreserve_mem_limit(node->adev,
564 					prange->npages * PAGE_SIZE,
565 					KFD_IOC_ALLOC_MEM_FLAGS_VRAM,
566 					node->xcp ? node->xcp->id : 0);
567 	return r < 0 ? r : 0;
568 }
569 
svm_migrate_page_free(struct page * page)570 static void svm_migrate_page_free(struct page *page)
571 {
572 	struct svm_range_bo *svm_bo = page->zone_device_data;
573 
574 	if (svm_bo) {
575 		pr_debug_ratelimited("ref: %d\n", kref_read(&svm_bo->kref));
576 		svm_range_bo_unref_async(svm_bo);
577 	}
578 }
579 
580 static int
svm_migrate_copy_to_ram(struct amdgpu_device * adev,struct svm_range * prange,struct migrate_vma * migrate,struct dma_fence ** mfence,dma_addr_t * scratch,uint64_t npages)581 svm_migrate_copy_to_ram(struct amdgpu_device *adev, struct svm_range *prange,
582 			struct migrate_vma *migrate, struct dma_fence **mfence,
583 			dma_addr_t *scratch, uint64_t npages)
584 {
585 	struct device *dev = adev->dev;
586 	uint64_t *src;
587 	dma_addr_t *dst;
588 	struct page *dpage;
589 	uint64_t i = 0, j;
590 	uint64_t addr;
591 	int r = 0;
592 
593 	pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms, prange->start,
594 		 prange->last);
595 
596 	addr = migrate->start;
597 
598 	src = (uint64_t *)(scratch + npages);
599 	dst = scratch;
600 
601 	for (i = 0, j = 0; i < npages; i++, addr += PAGE_SIZE) {
602 		struct page *spage;
603 
604 		spage = migrate_pfn_to_page(migrate->src[i]);
605 		if (!spage || !is_zone_device_page(spage)) {
606 			pr_debug("invalid page. Could be in CPU already svms 0x%p [0x%lx 0x%lx]\n",
607 				 prange->svms, prange->start, prange->last);
608 			if (j) {
609 				r = svm_migrate_copy_memory_gart(adev, dst + i - j,
610 								 src + i - j, j,
611 								 FROM_VRAM_TO_RAM,
612 								 mfence);
613 				if (r)
614 					goto out_oom;
615 				j = 0;
616 			}
617 			continue;
618 		}
619 		src[i] = svm_migrate_addr(adev, spage);
620 		if (j > 0 && src[i] != src[i - 1] + PAGE_SIZE) {
621 			r = svm_migrate_copy_memory_gart(adev, dst + i - j,
622 							 src + i - j, j,
623 							 FROM_VRAM_TO_RAM,
624 							 mfence);
625 			if (r)
626 				goto out_oom;
627 			j = 0;
628 		}
629 
630 		dpage = svm_migrate_get_sys_page(migrate->vma, addr);
631 		if (!dpage) {
632 			pr_debug("failed get page svms 0x%p [0x%lx 0x%lx]\n",
633 				 prange->svms, prange->start, prange->last);
634 			r = -ENOMEM;
635 			goto out_oom;
636 		}
637 
638 		dst[i] = dma_map_page(dev, dpage, 0, PAGE_SIZE, DMA_BIDIRECTIONAL);
639 		r = dma_mapping_error(dev, dst[i]);
640 		if (r) {
641 			dev_err(adev->dev, "%s: fail %d dma_map_page\n", __func__, r);
642 			goto out_oom;
643 		}
644 
645 		pr_debug_ratelimited("dma mapping dst to 0x%llx, pfn 0x%lx\n",
646 				     dst[i] >> PAGE_SHIFT, page_to_pfn(dpage));
647 
648 		migrate->dst[i] = migrate_pfn(page_to_pfn(dpage));
649 		j++;
650 	}
651 
652 	r = svm_migrate_copy_memory_gart(adev, dst + i - j, src + i - j, j,
653 					 FROM_VRAM_TO_RAM, mfence);
654 
655 out_oom:
656 	if (r) {
657 		pr_debug("failed %d copy to ram\n", r);
658 		while (i--) {
659 			svm_migrate_put_sys_page(dst[i]);
660 			migrate->dst[i] = 0;
661 		}
662 	}
663 
664 	return r;
665 }
666 
667 /**
668  * svm_migrate_vma_to_ram - migrate range inside one vma from device to system
669  *
670  * @prange: svm range structure
671  * @vma: vm_area_struct that range [start, end] belongs to
672  * @start: range start virtual address in pages
673  * @end: range end virtual address in pages
674  * @node: kfd node device to migrate from
675  * @trigger: reason of migration
676  * @fault_page: is from vmf->page, svm_migrate_to_ram(), this is CPU page fault callback
677  *
678  * Context: Process context, caller hold mmap read lock, prange->migrate_mutex
679  *
680  * Return:
681  *   negative values - indicate error
682  *   positive values or zero - number of pages got migrated
683  */
684 static long
svm_migrate_vma_to_ram(struct kfd_node * node,struct svm_range * prange,struct vm_area_struct * vma,uint64_t start,uint64_t end,uint32_t trigger,struct page * fault_page)685 svm_migrate_vma_to_ram(struct kfd_node *node, struct svm_range *prange,
686 		       struct vm_area_struct *vma, uint64_t start, uint64_t end,
687 		       uint32_t trigger, struct page *fault_page)
688 {
689 	struct kfd_process *p = container_of(prange->svms, struct kfd_process, svms);
690 	uint64_t npages = (end - start) >> PAGE_SHIFT;
691 	unsigned long upages = npages;
692 	unsigned long cpages = 0;
693 	unsigned long mpages = 0;
694 	struct amdgpu_device *adev = node->adev;
695 	struct kfd_process_device *pdd;
696 	struct dma_fence *mfence = NULL;
697 	struct migrate_vma migrate = { 0 };
698 	dma_addr_t *scratch;
699 	void *buf;
700 	int r = -ENOMEM;
701 
702 	memset(&migrate, 0, sizeof(migrate));
703 	migrate.vma = vma;
704 	migrate.start = start;
705 	migrate.end = end;
706 	migrate.pgmap_owner = SVM_ADEV_PGMAP_OWNER(adev);
707 	if (adev->gmc.xgmi.connected_to_cpu)
708 		migrate.flags = MIGRATE_VMA_SELECT_DEVICE_COHERENT;
709 	else
710 		migrate.flags = MIGRATE_VMA_SELECT_DEVICE_PRIVATE;
711 
712 	buf = kvcalloc(npages,
713 		       2 * sizeof(*migrate.src) + sizeof(uint64_t) + sizeof(dma_addr_t),
714 		       GFP_KERNEL);
715 	if (!buf)
716 		goto out;
717 
718 	migrate.src = buf;
719 	migrate.dst = migrate.src + npages;
720 	migrate.fault_page = fault_page;
721 	scratch = (dma_addr_t *)(migrate.dst + npages);
722 
723 	kfd_smi_event_migration_start(node, p->lead_thread->pid,
724 				      start >> PAGE_SHIFT, end >> PAGE_SHIFT,
725 				      node->id, 0, prange->prefetch_loc,
726 				      prange->preferred_loc, trigger);
727 
728 	r = migrate_vma_setup(&migrate);
729 	if (r) {
730 		dev_err(adev->dev, "%s: vma setup fail %d range [0x%lx 0x%lx]\n",
731 			__func__, r, prange->start, prange->last);
732 		goto out_free;
733 	}
734 
735 	cpages = migrate.cpages;
736 	if (!cpages) {
737 		pr_debug("failed collect migrate device pages [0x%lx 0x%lx]\n",
738 			 prange->start, prange->last);
739 		upages = svm_migrate_unsuccessful_pages(&migrate);
740 		goto out_free;
741 	}
742 	if (cpages != npages)
743 		pr_debug("partial migration, 0x%lx/0x%llx pages collected\n",
744 			 cpages, npages);
745 	else
746 		pr_debug("0x%lx pages collected\n", cpages);
747 
748 	r = svm_migrate_copy_to_ram(adev, prange, &migrate, &mfence,
749 				    scratch, npages);
750 	migrate_vma_pages(&migrate);
751 
752 	upages = svm_migrate_unsuccessful_pages(&migrate);
753 	pr_debug("unsuccessful/cpages/npages 0x%lx/0x%lx/0x%lx\n",
754 		 upages, cpages, migrate.npages);
755 
756 	svm_migrate_copy_done(adev, mfence);
757 	migrate_vma_finalize(&migrate);
758 
759 	svm_range_dma_unmap_dev(adev->dev, scratch, 0, npages);
760 
761 out_free:
762 	kvfree(buf);
763 	kfd_smi_event_migration_end(node, p->lead_thread->pid,
764 				    start >> PAGE_SHIFT, end >> PAGE_SHIFT,
765 				    node->id, 0, trigger, r);
766 out:
767 	if (!r && cpages) {
768 		mpages = cpages - upages;
769 		pdd = svm_range_get_pdd_by_node(prange, node);
770 		if (pdd)
771 			WRITE_ONCE(pdd->page_out, pdd->page_out + mpages);
772 	}
773 
774 	return r ? r : mpages;
775 }
776 
777 /**
778  * svm_migrate_vram_to_ram - migrate svm range from device to system
779  * @prange: range structure
780  * @mm: process mm, use current->mm if NULL
781  * @start_mgr: start page need be migrated to sys ram
782  * @last_mgr: last page need be migrated to sys ram
783  * @trigger: reason of migration
784  * @fault_page: is from vmf->page, svm_migrate_to_ram(), this is CPU page fault callback
785  *
786  * Context: Process context, caller hold mmap read lock, prange->migrate_mutex
787  *
788  * Return:
789  * 0 - OK, otherwise error code
790  */
svm_migrate_vram_to_ram(struct svm_range * prange,struct mm_struct * mm,unsigned long start_mgr,unsigned long last_mgr,uint32_t trigger,struct page * fault_page)791 int svm_migrate_vram_to_ram(struct svm_range *prange, struct mm_struct *mm,
792 			    unsigned long start_mgr, unsigned long last_mgr,
793 			    uint32_t trigger, struct page *fault_page)
794 {
795 	struct kfd_node *node;
796 	struct vm_area_struct *vma;
797 	unsigned long addr;
798 	unsigned long start;
799 	unsigned long end;
800 	unsigned long mpages = 0;
801 	long r = 0;
802 
803 	/* this pragne has no any vram page to migrate to sys ram */
804 	if (!prange->actual_loc) {
805 		pr_debug("[0x%lx 0x%lx] already migrated to ram\n",
806 			 prange->start, prange->last);
807 		return 0;
808 	}
809 
810 	if (start_mgr < prange->start || last_mgr > prange->last) {
811 		pr_debug("range [0x%lx 0x%lx] out prange [0x%lx 0x%lx]\n",
812 			 start_mgr, last_mgr, prange->start, prange->last);
813 		return -EFAULT;
814 	}
815 
816 	node = svm_range_get_node_by_id(prange, prange->actual_loc);
817 	if (!node) {
818 		pr_debug("failed to get kfd node by id 0x%x\n", prange->actual_loc);
819 		return -ENODEV;
820 	}
821 	pr_debug("svms 0x%p prange 0x%p [0x%lx 0x%lx] from gpu 0x%x to ram\n",
822 		 prange->svms, prange, start_mgr, last_mgr,
823 		 prange->actual_loc);
824 
825 	start = start_mgr << PAGE_SHIFT;
826 	end = (last_mgr + 1) << PAGE_SHIFT;
827 
828 	for (addr = start; addr < end;) {
829 		unsigned long next;
830 
831 		vma = vma_lookup(mm, addr);
832 		if (!vma) {
833 			pr_debug("failed to find vma for prange %p\n", prange);
834 			r = -EFAULT;
835 			break;
836 		}
837 
838 		next = min(vma->vm_end, end);
839 		r = svm_migrate_vma_to_ram(node, prange, vma, addr, next, trigger,
840 			fault_page);
841 		if (r < 0) {
842 			pr_debug("failed %ld to migrate prange %p\n", r, prange);
843 			break;
844 		} else {
845 			mpages += r;
846 		}
847 		addr = next;
848 	}
849 
850 	if (r >= 0) {
851 		prange->vram_pages -= mpages;
852 
853 		/* prange does not have vram page set its actual_loc to system
854 		 * and drop its svm_bo ref
855 		 */
856 		if (prange->vram_pages == 0 && prange->ttm_res) {
857 			prange->actual_loc = 0;
858 			svm_range_vram_node_free(prange);
859 		}
860 	}
861 
862 	return r < 0 ? r : 0;
863 }
864 
865 /**
866  * svm_migrate_vram_to_vram - migrate svm range from device to device
867  * @prange: range structure
868  * @best_loc: the device to migrate to
869  * @start: start page need be migrated to sys ram
870  * @last: last page need be migrated to sys ram
871  * @mm: process mm, use current->mm if NULL
872  * @trigger: reason of migration
873  *
874  * Context: Process context, caller hold mmap read lock, svms lock, prange lock
875  *
876  * migrate all vram pages in prange to sys ram, then migrate
877  * [start, last] pages from sys ram to gpu node best_loc.
878  *
879  * Return:
880  * 0 - OK, otherwise error code
881  */
882 static int
svm_migrate_vram_to_vram(struct svm_range * prange,uint32_t best_loc,unsigned long start,unsigned long last,struct mm_struct * mm,uint32_t trigger)883 svm_migrate_vram_to_vram(struct svm_range *prange, uint32_t best_loc,
884 			unsigned long start, unsigned long last,
885 			struct mm_struct *mm, uint32_t trigger)
886 {
887 	int r, retries = 3;
888 
889 	/*
890 	 * TODO: for both devices with PCIe large bar or on same xgmi hive, skip
891 	 * system memory as migration bridge
892 	 */
893 
894 	pr_debug("from gpu 0x%x to gpu 0x%x\n", prange->actual_loc, best_loc);
895 
896 	do {
897 		r = svm_migrate_vram_to_ram(prange, mm, prange->start, prange->last,
898 					    trigger, NULL);
899 		if (r)
900 			return r;
901 	} while (prange->actual_loc && --retries);
902 
903 	if (prange->actual_loc)
904 		return -EDEADLK;
905 
906 	return svm_migrate_ram_to_vram(prange, best_loc, start, last, mm, trigger);
907 }
908 
909 int
svm_migrate_to_vram(struct svm_range * prange,uint32_t best_loc,unsigned long start,unsigned long last,struct mm_struct * mm,uint32_t trigger)910 svm_migrate_to_vram(struct svm_range *prange, uint32_t best_loc,
911 		    unsigned long start, unsigned long last,
912 		    struct mm_struct *mm, uint32_t trigger)
913 {
914 	if  (!prange->actual_loc || prange->actual_loc == best_loc)
915 		return svm_migrate_ram_to_vram(prange, best_loc, start, last,
916 					       mm, trigger);
917 
918 	else
919 		return svm_migrate_vram_to_vram(prange, best_loc, start, last,
920 						mm, trigger);
921 
922 }
923 
924 /**
925  * svm_migrate_to_ram - CPU page fault handler
926  * @vmf: CPU vm fault vma, address
927  *
928  * Context: vm fault handler, caller holds the mmap read lock
929  *
930  * Return:
931  * 0 - OK
932  * VM_FAULT_SIGBUS - notice application to have SIGBUS page fault
933  */
svm_migrate_to_ram(struct vm_fault * vmf)934 static vm_fault_t svm_migrate_to_ram(struct vm_fault *vmf)
935 {
936 	unsigned long start, last, size;
937 	unsigned long addr = vmf->address;
938 	struct svm_range_bo *svm_bo;
939 	struct svm_range *prange;
940 	struct kfd_process *p;
941 	struct mm_struct *mm;
942 	int r = 0;
943 
944 	svm_bo = vmf->page->zone_device_data;
945 	if (!svm_bo) {
946 		pr_debug("failed get device page at addr 0x%lx\n", addr);
947 		return VM_FAULT_SIGBUS;
948 	}
949 	if (!mmget_not_zero(svm_bo->eviction_fence->mm)) {
950 		pr_debug("addr 0x%lx of process mm is destroyed\n", addr);
951 		return VM_FAULT_SIGBUS;
952 	}
953 
954 	mm = svm_bo->eviction_fence->mm;
955 	if (mm != vmf->vma->vm_mm)
956 		pr_debug("addr 0x%lx is COW mapping in child process\n", addr);
957 
958 	p = kfd_lookup_process_by_mm(mm);
959 	if (!p) {
960 		pr_debug("failed find process at fault address 0x%lx\n", addr);
961 		r = VM_FAULT_SIGBUS;
962 		goto out_mmput;
963 	}
964 	if (READ_ONCE(p->svms.faulting_task) == current) {
965 		pr_debug("skipping ram migration\n");
966 		r = 0;
967 		goto out_unref_process;
968 	}
969 
970 	pr_debug("CPU page fault svms 0x%p address 0x%lx\n", &p->svms, addr);
971 	addr >>= PAGE_SHIFT;
972 
973 	mutex_lock(&p->svms.lock);
974 
975 	prange = svm_range_from_addr(&p->svms, addr, NULL);
976 	if (!prange) {
977 		pr_debug("failed get range svms 0x%p addr 0x%lx\n", &p->svms, addr);
978 		r = -EFAULT;
979 		goto out_unlock_svms;
980 	}
981 
982 	mutex_lock(&prange->migrate_mutex);
983 
984 	if (!prange->actual_loc)
985 		goto out_unlock_prange;
986 
987 	/* Align migration range start and size to granularity size */
988 	size = 1UL << prange->granularity;
989 	start = max(ALIGN_DOWN(addr, size), prange->start);
990 	last = min(ALIGN(addr + 1, size) - 1, prange->last);
991 
992 	r = svm_migrate_vram_to_ram(prange, vmf->vma->vm_mm, start, last,
993 				    KFD_MIGRATE_TRIGGER_PAGEFAULT_CPU, vmf->page);
994 	if (r)
995 		pr_debug("failed %d migrate svms 0x%p range 0x%p [0x%lx 0x%lx]\n",
996 			r, prange->svms, prange, start, last);
997 
998 out_unlock_prange:
999 	mutex_unlock(&prange->migrate_mutex);
1000 out_unlock_svms:
1001 	mutex_unlock(&p->svms.lock);
1002 out_unref_process:
1003 	pr_debug("CPU fault svms 0x%p address 0x%lx done\n", &p->svms, addr);
1004 	kfd_unref_process(p);
1005 out_mmput:
1006 	mmput(mm);
1007 	return r ? VM_FAULT_SIGBUS : 0;
1008 }
1009 
1010 static const struct dev_pagemap_ops svm_migrate_pgmap_ops = {
1011 	.page_free		= svm_migrate_page_free,
1012 	.migrate_to_ram		= svm_migrate_to_ram,
1013 };
1014 
1015 /* Each VRAM page uses sizeof(struct page) on system memory */
1016 #define SVM_HMM_PAGE_STRUCT_SIZE(size) ((size)/PAGE_SIZE * sizeof(struct page))
1017 
kgd2kfd_init_zone_device(struct amdgpu_device * adev)1018 int kgd2kfd_init_zone_device(struct amdgpu_device *adev)
1019 {
1020 	struct amdgpu_kfd_dev *kfddev = &adev->kfd;
1021 	struct dev_pagemap *pgmap;
1022 	struct resource *res = NULL;
1023 	unsigned long size;
1024 	void *r;
1025 
1026 	/* Page migration works on gfx9 or newer */
1027 	if (amdgpu_ip_version(adev, GC_HWIP, 0) < IP_VERSION(9, 0, 1))
1028 		return -EINVAL;
1029 
1030 	if (adev->flags & AMD_IS_APU)
1031 		return 0;
1032 
1033 	pgmap = &kfddev->pgmap;
1034 	memset(pgmap, 0, sizeof(*pgmap));
1035 
1036 	/* TODO: register all vram to HMM for now.
1037 	 * should remove reserved size
1038 	 */
1039 	size = ALIGN(adev->gmc.real_vram_size, 2ULL << 20);
1040 	if (adev->gmc.xgmi.connected_to_cpu) {
1041 		pgmap->range.start = adev->gmc.aper_base;
1042 		pgmap->range.end = adev->gmc.aper_base + adev->gmc.aper_size - 1;
1043 		pgmap->type = MEMORY_DEVICE_COHERENT;
1044 	} else {
1045 		res = devm_request_free_mem_region(adev->dev, &iomem_resource, size);
1046 		if (IS_ERR(res))
1047 			return PTR_ERR(res);
1048 		pgmap->range.start = res->start;
1049 		pgmap->range.end = res->end;
1050 		pgmap->type = MEMORY_DEVICE_PRIVATE;
1051 	}
1052 
1053 	pgmap->nr_range = 1;
1054 	pgmap->ops = &svm_migrate_pgmap_ops;
1055 	pgmap->owner = SVM_ADEV_PGMAP_OWNER(adev);
1056 	pgmap->flags = 0;
1057 	/* Device manager releases device-specific resources, memory region and
1058 	 * pgmap when driver disconnects from device.
1059 	 */
1060 	r = devm_memremap_pages(adev->dev, pgmap);
1061 	if (IS_ERR(r)) {
1062 		pr_err("failed to register HMM device memory\n");
1063 		if (pgmap->type == MEMORY_DEVICE_PRIVATE)
1064 			devm_release_mem_region(adev->dev, res->start, resource_size(res));
1065 		/* Disable SVM support capability */
1066 		pgmap->type = 0;
1067 		return PTR_ERR(r);
1068 	}
1069 
1070 	pr_debug("reserve %ldMB system memory for VRAM pages struct\n",
1071 		 SVM_HMM_PAGE_STRUCT_SIZE(size) >> 20);
1072 
1073 	amdgpu_amdkfd_reserve_system_mem(SVM_HMM_PAGE_STRUCT_SIZE(size));
1074 
1075 	pr_info("HMM registered %ldMB device memory\n", size >> 20);
1076 
1077 	return 0;
1078 }
1079