xref: /openbmc/linux/drivers/gpu/drm/ttm/ttm_tt.c (revision f5b8b297) 
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 		pr_err("Failed allocating page table\n");
246 		return -ENOMEM;
247 	}
248 	return 0;
249 }
250 EXPORT_SYMBOL(ttm_tt_init);
251 
252 void ttm_tt_fini(struct ttm_tt *ttm)
253 {
254 	kvfree(ttm->pages);
255 	ttm->pages = NULL;
256 }
257 EXPORT_SYMBOL(ttm_tt_fini);
258 
259 int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_buffer_object *bo,
260 		    uint32_t page_flags)
261 {
262 	struct ttm_tt *ttm = &ttm_dma->ttm;
263 
264 	ttm_tt_init_fields(ttm, bo, page_flags);
265 
266 	INIT_LIST_HEAD(&ttm_dma->pages_list);
267 	if (ttm_dma_tt_alloc_page_directory(ttm_dma)) {
268 		pr_err("Failed allocating page table\n");
269 		return -ENOMEM;
270 	}
271 	return 0;
272 }
273 EXPORT_SYMBOL(ttm_dma_tt_init);
274 
275 int ttm_sg_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_buffer_object *bo,
276 		   uint32_t page_flags)
277 {
278 	struct ttm_tt *ttm = &ttm_dma->ttm;
279 	int ret;
280 
281 	ttm_tt_init_fields(ttm, bo, page_flags);
282 
283 	INIT_LIST_HEAD(&ttm_dma->pages_list);
284 	if (page_flags & TTM_PAGE_FLAG_SG)
285 		ret = ttm_sg_tt_alloc_page_directory(ttm_dma);
286 	else
287 		ret = ttm_dma_tt_alloc_page_directory(ttm_dma);
288 	if (ret) {
289 		pr_err("Failed allocating page table\n");
290 		return -ENOMEM;
291 	}
292 	return 0;
293 }
294 EXPORT_SYMBOL(ttm_sg_tt_init);
295 
296 void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma)
297 {
298 	struct ttm_tt *ttm = &ttm_dma->ttm;
299 
300 	if (ttm->pages)
301 		kvfree(ttm->pages);
302 	else
303 		kvfree(ttm_dma->dma_address);
304 	ttm->pages = NULL;
305 	ttm_dma->dma_address = NULL;
306 }
307 EXPORT_SYMBOL(ttm_dma_tt_fini);
308 
309 void ttm_tt_unbind(struct ttm_tt *ttm)
310 {
311 	if (ttm->state == tt_bound) {
312 		ttm->func->unbind(ttm);
313 		ttm->state = tt_unbound;
314 	}
315 }
316 
317 int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem,
318 		struct ttm_operation_ctx *ctx)
319 {
320 	int ret = 0;
321 
322 	if (!ttm)
323 		return -EINVAL;
324 
325 	if (ttm->state == tt_bound)
326 		return 0;
327 
328 	ret = ttm_tt_populate(ttm, ctx);
329 	if (ret)
330 		return ret;
331 
332 	ret = ttm->func->bind(ttm, bo_mem);
333 	if (unlikely(ret != 0))
334 		return ret;
335 
336 	ttm->state = tt_bound;
337 
338 	return 0;
339 }
340 EXPORT_SYMBOL(ttm_tt_bind);
341 
342 int ttm_tt_swapin(struct ttm_tt *ttm)
343 {
344 	struct address_space *swap_space;
345 	struct file *swap_storage;
346 	struct page *from_page;
347 	struct page *to_page;
348 	int i;
349 	int ret = -ENOMEM;
350 
351 	swap_storage = ttm->swap_storage;
352 	BUG_ON(swap_storage == NULL);
353 
354 	swap_space = swap_storage->f_mapping;
355 
356 	for (i = 0; i < ttm->num_pages; ++i) {
357 		gfp_t gfp_mask = mapping_gfp_mask(swap_space);
358 
359 		gfp_mask |= (ttm->page_flags & TTM_PAGE_FLAG_NO_RETRY ? __GFP_RETRY_MAYFAIL : 0);
360 		from_page = shmem_read_mapping_page_gfp(swap_space, i, gfp_mask);
361 
362 		if (IS_ERR(from_page)) {
363 			ret = PTR_ERR(from_page);
364 			goto out_err;
365 		}
366 		to_page = ttm->pages[i];
367 		if (unlikely(to_page == NULL))
368 			goto out_err;
369 
370 		copy_highpage(to_page, from_page);
371 		put_page(from_page);
372 	}
373 
374 	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP))
375 		fput(swap_storage);
376 	ttm->swap_storage = NULL;
377 	ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
378 
379 	return 0;
380 out_err:
381 	return ret;
382 }
383 
384 int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistent_swap_storage)
385 {
386 	struct address_space *swap_space;
387 	struct file *swap_storage;
388 	struct page *from_page;
389 	struct page *to_page;
390 	int i;
391 	int ret = -ENOMEM;
392 
393 	BUG_ON(ttm->state != tt_unbound && ttm->state != tt_unpopulated);
394 	BUG_ON(ttm->caching_state != tt_cached);
395 
396 	if (!persistent_swap_storage) {
397 		swap_storage = shmem_file_setup("ttm swap",
398 						ttm->num_pages << PAGE_SHIFT,
399 						0);
400 		if (IS_ERR(swap_storage)) {
401 			pr_err("Failed allocating swap storage\n");
402 			return PTR_ERR(swap_storage);
403 		}
404 	} else {
405 		swap_storage = persistent_swap_storage;
406 	}
407 
408 	swap_space = swap_storage->f_mapping;
409 
410 	for (i = 0; i < ttm->num_pages; ++i) {
411 		gfp_t gfp_mask = mapping_gfp_mask(swap_space);
412 
413 		gfp_mask |= (ttm->page_flags & TTM_PAGE_FLAG_NO_RETRY ? __GFP_RETRY_MAYFAIL : 0);
414 
415 		from_page = ttm->pages[i];
416 		if (unlikely(from_page == NULL))
417 			continue;
418 
419 		to_page = shmem_read_mapping_page_gfp(swap_space, i, gfp_mask);
420 		if (IS_ERR(to_page)) {
421 			ret = PTR_ERR(to_page);
422 			goto out_err;
423 		}
424 		copy_highpage(to_page, from_page);
425 		set_page_dirty(to_page);
426 		mark_page_accessed(to_page);
427 		put_page(to_page);
428 	}
429 
430 	ttm_tt_unpopulate(ttm);
431 	ttm->swap_storage = swap_storage;
432 	ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
433 	if (persistent_swap_storage)
434 		ttm->page_flags |= TTM_PAGE_FLAG_PERSISTENT_SWAP;
435 
436 	return 0;
437 out_err:
438 	if (!persistent_swap_storage)
439 		fput(swap_storage);
440 
441 	return ret;
442 }
443 
444 static void ttm_tt_add_mapping(struct ttm_tt *ttm)
445 {
446 	pgoff_t i;
447 
448 	if (ttm->page_flags & TTM_PAGE_FLAG_SG)
449 		return;
450 
451 	for (i = 0; i < ttm->num_pages; ++i)
452 		ttm->pages[i]->mapping = ttm->bdev->dev_mapping;
453 }
454 
455 int ttm_tt_populate(struct ttm_tt *ttm, struct ttm_operation_ctx *ctx)
456 {
457 	int ret;
458 
459 	if (ttm->state != tt_unpopulated)
460 		return 0;
461 
462 	if (ttm->bdev->driver->ttm_tt_populate)
463 		ret = ttm->bdev->driver->ttm_tt_populate(ttm, ctx);
464 	else
465 		ret = ttm_pool_populate(ttm, ctx);
466 	if (!ret)
467 		ttm_tt_add_mapping(ttm);
468 	return ret;
469 }
470 
471 static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
472 {
473 	pgoff_t i;
474 	struct page **page = ttm->pages;
475 
476 	if (ttm->page_flags & TTM_PAGE_FLAG_SG)
477 		return;
478 
479 	for (i = 0; i < ttm->num_pages; ++i) {
480 		(*page)->mapping = NULL;
481 		(*page++)->index = 0;
482 	}
483 }
484 
485 void ttm_tt_unpopulate(struct ttm_tt *ttm)
486 {
487 	if (ttm->state == tt_unpopulated)
488 		return;
489 
490 	ttm_tt_clear_mapping(ttm);
491 	if (ttm->bdev->driver->ttm_tt_unpopulate)
492 		ttm->bdev->driver->ttm_tt_unpopulate(ttm);
493 	else
494 		ttm_pool_unpopulate(ttm);
495 }
496