xref: /openbmc/linux/drivers/gpu/drm/ttm/ttm_tt.c (revision 55fd7e02) 
1 /* SPDX-License-Identifier: GPL-2.0 OR MIT */
2 /**************************************************************************
3  *
4  * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
5  * All Rights Reserved.
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a
8  * copy of this software and associated documentation files (the
9  * "Software"), to deal in the Software without restriction, including
10  * without limitation the rights to use, copy, modify, merge, publish,
11  * distribute, sub license, and/or sell copies of the Software, and to
12  * permit persons to whom the Software is furnished to do so, subject to
13  * the following conditions:
14  *
15  * The above copyright notice and this permission notice (including the
16  * next paragraph) shall be included in all copies or substantial portions
17  * of the Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
22  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
23  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
24  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
25  * USE OR OTHER DEALINGS IN THE SOFTWARE.
26  *
27  **************************************************************************/
28 /*
29  * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
30  */
31 
32 #define pr_fmt(fmt) "[TTM] " fmt
33 
34 #include <linux/sched.h>
35 #include <linux/pagemap.h>
36 #include <linux/shmem_fs.h>
37 #include <linux/file.h>
38 #include <drm/drm_cache.h>
39 #include <drm/ttm/ttm_bo_driver.h>
40 #include <drm/ttm/ttm_page_alloc.h>
41 #include <drm/ttm/ttm_set_memory.h>
42 
43 /**
44  * Allocates a ttm structure for the given BO.
45  */
46 int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc)
47 {
48 	struct ttm_bo_device *bdev = bo->bdev;
49 	uint32_t page_flags = 0;
50 
51 	dma_resv_assert_held(bo->base.resv);
52 
53 	if (bdev->need_dma32)
54 		page_flags |= TTM_PAGE_FLAG_DMA32;
55 
56 	if (bdev->no_retry)
57 		page_flags |= TTM_PAGE_FLAG_NO_RETRY;
58 
59 	switch (bo->type) {
60 	case ttm_bo_type_device:
61 		if (zero_alloc)
62 			page_flags |= TTM_PAGE_FLAG_ZERO_ALLOC;
63 		break;
64 	case ttm_bo_type_kernel:
65 		break;
66 	case ttm_bo_type_sg:
67 		page_flags |= TTM_PAGE_FLAG_SG;
68 		break;
69 	default:
70 		bo->ttm = NULL;
71 		pr_err("Illegal buffer object type\n");
72 		return -EINVAL;
73 	}
74 
75 	bo->ttm = bdev->driver->ttm_tt_create(bo, page_flags);
76 	if (unlikely(bo->ttm == NULL))
77 		return -ENOMEM;
78 
79 	return 0;
80 }
81 
82 /**
83  * Allocates storage for pointers to the pages that back the ttm.
84  */
85 static int ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
86 {
87 	ttm->pages = kvmalloc_array(ttm->num_pages, sizeof(void*),
88 			GFP_KERNEL | __GFP_ZERO);
89 	if (!ttm->pages)
90 		return -ENOMEM;
91 	return 0;
92 }
93 
94 static int ttm_dma_tt_alloc_page_directory(struct ttm_dma_tt *ttm)
95 {
96 	ttm->ttm.pages = kvmalloc_array(ttm->ttm.num_pages,
97 					  sizeof(*ttm->ttm.pages) +
98 					  sizeof(*ttm->dma_address),
99 					  GFP_KERNEL | __GFP_ZERO);
100 	if (!ttm->ttm.pages)
101 		return -ENOMEM;
102 	ttm->dma_address = (void *) (ttm->ttm.pages + ttm->ttm.num_pages);
103 	return 0;
104 }
105 
106 static int ttm_sg_tt_alloc_page_directory(struct ttm_dma_tt *ttm)
107 {
108 	ttm->dma_address = kvmalloc_array(ttm->ttm.num_pages,
109 					  sizeof(*ttm->dma_address),
110 					  GFP_KERNEL | __GFP_ZERO);
111 	if (!ttm->dma_address)
112 		return -ENOMEM;
113 	return 0;
114 }
115 
116 static int ttm_tt_set_page_caching(struct page *p,
117 				   enum ttm_caching_state c_old,
118 				   enum ttm_caching_state c_new)
119 {
120 	int ret = 0;
121 
122 	if (PageHighMem(p))
123 		return 0;
124 
125 	if (c_old != tt_cached) {
126 		/* p isn't in the default caching state, set it to
127 		 * writeback first to free its current memtype. */
128 
129 		ret = ttm_set_pages_wb(p, 1);
130 		if (ret)
131 			return ret;
132 	}
133 
134 	if (c_new == tt_wc)
135 		ret = ttm_set_pages_wc(p, 1);
136 	else if (c_new == tt_uncached)
137 		ret = ttm_set_pages_uc(p, 1);
138 
139 	return ret;
140 }
141 
142 /*
143  * Change caching policy for the linear kernel map
144  * for range of pages in a ttm.
145  */
146 
147 static int ttm_tt_set_caching(struct ttm_tt *ttm,
148 			      enum ttm_caching_state c_state)
149 {
150 	int i, j;
151 	struct page *cur_page;
152 	int ret;
153 
154 	if (ttm->caching_state == c_state)
155 		return 0;
156 
157 	if (ttm->state == tt_unpopulated) {
158 		/* Change caching but don't populate */
159 		ttm->caching_state = c_state;
160 		return 0;
161 	}
162 
163 	if (ttm->caching_state == tt_cached)
164 		drm_clflush_pages(ttm->pages, ttm->num_pages);
165 
166 	for (i = 0; i < ttm->num_pages; ++i) {
167 		cur_page = ttm->pages[i];
168 		if (likely(cur_page != NULL)) {
169 			ret = ttm_tt_set_page_caching(cur_page,
170 						      ttm->caching_state,
171 						      c_state);
172 			if (unlikely(ret != 0))
173 				goto out_err;
174 		}
175 	}
176 
177 	ttm->caching_state = c_state;
178 
179 	return 0;
180 
181 out_err:
182 	for (j = 0; j < i; ++j) {
183 		cur_page = ttm->pages[j];
184 		if (likely(cur_page != NULL)) {
185 			(void)ttm_tt_set_page_caching(cur_page, c_state,
186 						      ttm->caching_state);
187 		}
188 	}
189 
190 	return ret;
191 }
192 
193 int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement)
194 {
195 	enum ttm_caching_state state;
196 
197 	if (placement & TTM_PL_FLAG_WC)
198 		state = tt_wc;
199 	else if (placement & TTM_PL_FLAG_UNCACHED)
200 		state = tt_uncached;
201 	else
202 		state = tt_cached;
203 
204 	return ttm_tt_set_caching(ttm, state);
205 }
206 EXPORT_SYMBOL(ttm_tt_set_placement_caching);
207 
208 void ttm_tt_destroy(struct ttm_tt *ttm)
209 {
210 	if (ttm == NULL)
211 		return;
212 
213 	ttm_tt_unbind(ttm);
214 
215 	if (ttm->state == tt_unbound)
216 		ttm_tt_unpopulate(ttm);
217 
218 	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP) &&
219 	    ttm->swap_storage)
220 		fput(ttm->swap_storage);
221 
222 	ttm->swap_storage = NULL;
223 	ttm->func->destroy(ttm);
224 }
225 
226 static void ttm_tt_init_fields(struct ttm_tt *ttm,
227 			       struct ttm_buffer_object *bo,
228 			       uint32_t page_flags)
229 {
230 	ttm->bdev = bo->bdev;
231 	ttm->num_pages = bo->num_pages;
232 	ttm->caching_state = tt_cached;
233 	ttm->page_flags = page_flags;
234 	ttm->state = tt_unpopulated;
235 	ttm->swap_storage = NULL;
236 	ttm->sg = bo->sg;
237 }
238 
239 int ttm_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
240 		uint32_t page_flags)
241 {
242 	ttm_tt_init_fields(ttm, bo, page_flags);
243 
244 	if (ttm_tt_alloc_page_directory(ttm)) {
245 		ttm_tt_destroy(ttm);
246 		pr_err("Failed allocating page table\n");
247 		return -ENOMEM;
248 	}
249 	return 0;
250 }
251 EXPORT_SYMBOL(ttm_tt_init);
252 
253 void ttm_tt_fini(struct ttm_tt *ttm)
254 {
255 	kvfree(ttm->pages);
256 	ttm->pages = NULL;
257 }
258 EXPORT_SYMBOL(ttm_tt_fini);
259 
260 int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_buffer_object *bo,
261 		    uint32_t page_flags)
262 {
263 	struct ttm_tt *ttm = &ttm_dma->ttm;
264 
265 	ttm_tt_init_fields(ttm, bo, page_flags);
266 
267 	INIT_LIST_HEAD(&ttm_dma->pages_list);
268 	if (ttm_dma_tt_alloc_page_directory(ttm_dma)) {
269 		ttm_tt_destroy(ttm);
270 		pr_err("Failed allocating page table\n");
271 		return -ENOMEM;
272 	}
273 	return 0;
274 }
275 EXPORT_SYMBOL(ttm_dma_tt_init);
276 
277 int ttm_sg_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_buffer_object *bo,
278 		   uint32_t page_flags)
279 {
280 	struct ttm_tt *ttm = &ttm_dma->ttm;
281 	int ret;
282 
283 	ttm_tt_init_fields(ttm, bo, page_flags);
284 
285 	INIT_LIST_HEAD(&ttm_dma->pages_list);
286 	if (page_flags & TTM_PAGE_FLAG_SG)
287 		ret = ttm_sg_tt_alloc_page_directory(ttm_dma);
288 	else
289 		ret = ttm_dma_tt_alloc_page_directory(ttm_dma);
290 	if (ret) {
291 		ttm_tt_destroy(ttm);
292 		pr_err("Failed allocating page table\n");
293 		return -ENOMEM;
294 	}
295 	return 0;
296 }
297 EXPORT_SYMBOL(ttm_sg_tt_init);
298 
299 void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma)
300 {
301 	struct ttm_tt *ttm = &ttm_dma->ttm;
302 
303 	if (ttm->pages)
304 		kvfree(ttm->pages);
305 	else
306 		kvfree(ttm_dma->dma_address);
307 	ttm->pages = NULL;
308 	ttm_dma->dma_address = NULL;
309 }
310 EXPORT_SYMBOL(ttm_dma_tt_fini);
311 
312 void ttm_tt_unbind(struct ttm_tt *ttm)
313 {
314 	int ret;
315 
316 	if (ttm->state == tt_bound) {
317 		ret = ttm->func->unbind(ttm);
318 		BUG_ON(ret);
319 		ttm->state = tt_unbound;
320 	}
321 }
322 
323 int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem,
324 		struct ttm_operation_ctx *ctx)
325 {
326 	int ret = 0;
327 
328 	if (!ttm)
329 		return -EINVAL;
330 
331 	if (ttm->state == tt_bound)
332 		return 0;
333 
334 	ret = ttm_tt_populate(ttm, ctx);
335 	if (ret)
336 		return ret;
337 
338 	ret = ttm->func->bind(ttm, bo_mem);
339 	if (unlikely(ret != 0))
340 		return ret;
341 
342 	ttm->state = tt_bound;
343 
344 	return 0;
345 }
346 EXPORT_SYMBOL(ttm_tt_bind);
347 
348 int ttm_tt_swapin(struct ttm_tt *ttm)
349 {
350 	struct address_space *swap_space;
351 	struct file *swap_storage;
352 	struct page *from_page;
353 	struct page *to_page;
354 	int i;
355 	int ret = -ENOMEM;
356 
357 	swap_storage = ttm->swap_storage;
358 	BUG_ON(swap_storage == NULL);
359 
360 	swap_space = swap_storage->f_mapping;
361 
362 	for (i = 0; i < ttm->num_pages; ++i) {
363 		gfp_t gfp_mask = mapping_gfp_mask(swap_space);
364 
365 		gfp_mask |= (ttm->page_flags & TTM_PAGE_FLAG_NO_RETRY ? __GFP_RETRY_MAYFAIL : 0);
366 		from_page = shmem_read_mapping_page_gfp(swap_space, i, gfp_mask);
367 
368 		if (IS_ERR(from_page)) {
369 			ret = PTR_ERR(from_page);
370 			goto out_err;
371 		}
372 		to_page = ttm->pages[i];
373 		if (unlikely(to_page == NULL))
374 			goto out_err;
375 
376 		copy_highpage(to_page, from_page);
377 		put_page(from_page);
378 	}
379 
380 	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP))
381 		fput(swap_storage);
382 	ttm->swap_storage = NULL;
383 	ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
384 
385 	return 0;
386 out_err:
387 	return ret;
388 }
389 
390 int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistent_swap_storage)
391 {
392 	struct address_space *swap_space;
393 	struct file *swap_storage;
394 	struct page *from_page;
395 	struct page *to_page;
396 	int i;
397 	int ret = -ENOMEM;
398 
399 	BUG_ON(ttm->state != tt_unbound && ttm->state != tt_unpopulated);
400 	BUG_ON(ttm->caching_state != tt_cached);
401 
402 	if (!persistent_swap_storage) {
403 		swap_storage = shmem_file_setup("ttm swap",
404 						ttm->num_pages << PAGE_SHIFT,
405 						0);
406 		if (IS_ERR(swap_storage)) {
407 			pr_err("Failed allocating swap storage\n");
408 			return PTR_ERR(swap_storage);
409 		}
410 	} else {
411 		swap_storage = persistent_swap_storage;
412 	}
413 
414 	swap_space = swap_storage->f_mapping;
415 
416 	for (i = 0; i < ttm->num_pages; ++i) {
417 		gfp_t gfp_mask = mapping_gfp_mask(swap_space);
418 
419 		gfp_mask |= (ttm->page_flags & TTM_PAGE_FLAG_NO_RETRY ? __GFP_RETRY_MAYFAIL : 0);
420 
421 		from_page = ttm->pages[i];
422 		if (unlikely(from_page == NULL))
423 			continue;
424 
425 		to_page = shmem_read_mapping_page_gfp(swap_space, i, gfp_mask);
426 		if (IS_ERR(to_page)) {
427 			ret = PTR_ERR(to_page);
428 			goto out_err;
429 		}
430 		copy_highpage(to_page, from_page);
431 		set_page_dirty(to_page);
432 		mark_page_accessed(to_page);
433 		put_page(to_page);
434 	}
435 
436 	ttm_tt_unpopulate(ttm);
437 	ttm->swap_storage = swap_storage;
438 	ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
439 	if (persistent_swap_storage)
440 		ttm->page_flags |= TTM_PAGE_FLAG_PERSISTENT_SWAP;
441 
442 	return 0;
443 out_err:
444 	if (!persistent_swap_storage)
445 		fput(swap_storage);
446 
447 	return ret;
448 }
449 
450 static void ttm_tt_add_mapping(struct ttm_tt *ttm)
451 {
452 	pgoff_t i;
453 
454 	if (ttm->page_flags & TTM_PAGE_FLAG_SG)
455 		return;
456 
457 	for (i = 0; i < ttm->num_pages; ++i)
458 		ttm->pages[i]->mapping = ttm->bdev->dev_mapping;
459 }
460 
461 int ttm_tt_populate(struct ttm_tt *ttm, struct ttm_operation_ctx *ctx)
462 {
463 	int ret;
464 
465 	if (ttm->state != tt_unpopulated)
466 		return 0;
467 
468 	if (ttm->bdev->driver->ttm_tt_populate)
469 		ret = ttm->bdev->driver->ttm_tt_populate(ttm, ctx);
470 	else
471 		ret = ttm_pool_populate(ttm, ctx);
472 	if (!ret)
473 		ttm_tt_add_mapping(ttm);
474 	return ret;
475 }
476 
477 static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
478 {
479 	pgoff_t i;
480 	struct page **page = ttm->pages;
481 
482 	if (ttm->page_flags & TTM_PAGE_FLAG_SG)
483 		return;
484 
485 	for (i = 0; i < ttm->num_pages; ++i) {
486 		(*page)->mapping = NULL;
487 		(*page++)->index = 0;
488 	}
489 }
490 
491 void ttm_tt_unpopulate(struct ttm_tt *ttm)
492 {
493 	if (ttm->state == tt_unpopulated)
494 		return;
495 
496 	ttm_tt_clear_mapping(ttm);
497 	if (ttm->bdev->driver->ttm_tt_unpopulate)
498 		ttm->bdev->driver->ttm_tt_unpopulate(ttm);
499 	else
500 		ttm_pool_unpopulate(ttm);
501 }
502