xref: /openbmc/linux/drivers/gpu/drm/ttm/ttm_tt.c (revision 20e2fc42) 
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 void ttm_tt_init_fields(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
227 			uint32_t page_flags)
228 {
229 	ttm->bdev = bo->bdev;
230 	ttm->num_pages = bo->num_pages;
231 	ttm->caching_state = tt_cached;
232 	ttm->page_flags = page_flags;
233 	ttm->state = tt_unpopulated;
234 	ttm->swap_storage = NULL;
235 	ttm->sg = bo->sg;
236 }
237 
238 int ttm_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
239 		uint32_t page_flags)
240 {
241 	ttm_tt_init_fields(ttm, bo, page_flags);
242 
243 	if (ttm_tt_alloc_page_directory(ttm)) {
244 		ttm_tt_destroy(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 		ttm_tt_destroy(ttm);
269 		pr_err("Failed allocating page table\n");
270 		return -ENOMEM;
271 	}
272 	return 0;
273 }
274 EXPORT_SYMBOL(ttm_dma_tt_init);
275 
276 int ttm_sg_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_buffer_object *bo,
277 		   uint32_t page_flags)
278 {
279 	struct ttm_tt *ttm = &ttm_dma->ttm;
280 	int ret;
281 
282 	ttm_tt_init_fields(ttm, bo, page_flags);
283 
284 	INIT_LIST_HEAD(&ttm_dma->pages_list);
285 	if (page_flags & TTM_PAGE_FLAG_SG)
286 		ret = ttm_sg_tt_alloc_page_directory(ttm_dma);
287 	else
288 		ret = ttm_dma_tt_alloc_page_directory(ttm_dma);
289 	if (ret) {
290 		ttm_tt_destroy(ttm);
291 		pr_err("Failed allocating page table\n");
292 		return -ENOMEM;
293 	}
294 	return 0;
295 }
296 EXPORT_SYMBOL(ttm_sg_tt_init);
297 
298 void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma)
299 {
300 	struct ttm_tt *ttm = &ttm_dma->ttm;
301 
302 	if (ttm->pages)
303 		kvfree(ttm->pages);
304 	else
305 		kvfree(ttm_dma->dma_address);
306 	ttm->pages = NULL;
307 	ttm_dma->dma_address = NULL;
308 }
309 EXPORT_SYMBOL(ttm_dma_tt_fini);
310 
311 void ttm_tt_unbind(struct ttm_tt *ttm)
312 {
313 	int ret;
314 
315 	if (ttm->state == tt_bound) {
316 		ret = ttm->func->unbind(ttm);
317 		BUG_ON(ret);
318 		ttm->state = tt_unbound;
319 	}
320 }
321 
322 int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem,
323 		struct ttm_operation_ctx *ctx)
324 {
325 	int ret = 0;
326 
327 	if (!ttm)
328 		return -EINVAL;
329 
330 	if (ttm->state == tt_bound)
331 		return 0;
332 
333 	ret = ttm_tt_populate(ttm, ctx);
334 	if (ret)
335 		return ret;
336 
337 	ret = ttm->func->bind(ttm, bo_mem);
338 	if (unlikely(ret != 0))
339 		return ret;
340 
341 	ttm->state = tt_bound;
342 
343 	return 0;
344 }
345 EXPORT_SYMBOL(ttm_tt_bind);
346 
347 int ttm_tt_swapin(struct ttm_tt *ttm)
348 {
349 	struct address_space *swap_space;
350 	struct file *swap_storage;
351 	struct page *from_page;
352 	struct page *to_page;
353 	int i;
354 	int ret = -ENOMEM;
355 
356 	swap_storage = ttm->swap_storage;
357 	BUG_ON(swap_storage == NULL);
358 
359 	swap_space = swap_storage->f_mapping;
360 
361 	for (i = 0; i < ttm->num_pages; ++i) {
362 		gfp_t gfp_mask = mapping_gfp_mask(swap_space);
363 
364 		gfp_mask |= (ttm->page_flags & TTM_PAGE_FLAG_NO_RETRY ? __GFP_RETRY_MAYFAIL : 0);
365 		from_page = shmem_read_mapping_page_gfp(swap_space, i, gfp_mask);
366 
367 		if (IS_ERR(from_page)) {
368 			ret = PTR_ERR(from_page);
369 			goto out_err;
370 		}
371 		to_page = ttm->pages[i];
372 		if (unlikely(to_page == NULL))
373 			goto out_err;
374 
375 		copy_highpage(to_page, from_page);
376 		put_page(from_page);
377 	}
378 
379 	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP))
380 		fput(swap_storage);
381 	ttm->swap_storage = NULL;
382 	ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
383 
384 	return 0;
385 out_err:
386 	return ret;
387 }
388 
389 int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistent_swap_storage)
390 {
391 	struct address_space *swap_space;
392 	struct file *swap_storage;
393 	struct page *from_page;
394 	struct page *to_page;
395 	int i;
396 	int ret = -ENOMEM;
397 
398 	BUG_ON(ttm->state != tt_unbound && ttm->state != tt_unpopulated);
399 	BUG_ON(ttm->caching_state != tt_cached);
400 
401 	if (!persistent_swap_storage) {
402 		swap_storage = shmem_file_setup("ttm swap",
403 						ttm->num_pages << PAGE_SHIFT,
404 						0);
405 		if (IS_ERR(swap_storage)) {
406 			pr_err("Failed allocating swap storage\n");
407 			return PTR_ERR(swap_storage);
408 		}
409 	} else {
410 		swap_storage = persistent_swap_storage;
411 	}
412 
413 	swap_space = swap_storage->f_mapping;
414 
415 	for (i = 0; i < ttm->num_pages; ++i) {
416 		gfp_t gfp_mask = mapping_gfp_mask(swap_space);
417 
418 		gfp_mask |= (ttm->page_flags & TTM_PAGE_FLAG_NO_RETRY ? __GFP_RETRY_MAYFAIL : 0);
419 
420 		from_page = ttm->pages[i];
421 		if (unlikely(from_page == NULL))
422 			continue;
423 
424 		to_page = shmem_read_mapping_page_gfp(swap_space, i, gfp_mask);
425 		if (IS_ERR(to_page)) {
426 			ret = PTR_ERR(to_page);
427 			goto out_err;
428 		}
429 		copy_highpage(to_page, from_page);
430 		set_page_dirty(to_page);
431 		mark_page_accessed(to_page);
432 		put_page(to_page);
433 	}
434 
435 	ttm_tt_unpopulate(ttm);
436 	ttm->swap_storage = swap_storage;
437 	ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
438 	if (persistent_swap_storage)
439 		ttm->page_flags |= TTM_PAGE_FLAG_PERSISTENT_SWAP;
440 
441 	return 0;
442 out_err:
443 	if (!persistent_swap_storage)
444 		fput(swap_storage);
445 
446 	return ret;
447 }
448 
449 static void ttm_tt_add_mapping(struct ttm_tt *ttm)
450 {
451 	pgoff_t i;
452 
453 	if (ttm->page_flags & TTM_PAGE_FLAG_SG)
454 		return;
455 
456 	for (i = 0; i < ttm->num_pages; ++i)
457 		ttm->pages[i]->mapping = ttm->bdev->dev_mapping;
458 }
459 
460 int ttm_tt_populate(struct ttm_tt *ttm, struct ttm_operation_ctx *ctx)
461 {
462 	int ret;
463 
464 	if (ttm->state != tt_unpopulated)
465 		return 0;
466 
467 	if (ttm->bdev->driver->ttm_tt_populate)
468 		ret = ttm->bdev->driver->ttm_tt_populate(ttm, ctx);
469 	else
470 		ret = ttm_pool_populate(ttm, ctx);
471 	if (!ret)
472 		ttm_tt_add_mapping(ttm);
473 	return ret;
474 }
475 
476 static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
477 {
478 	pgoff_t i;
479 	struct page **page = ttm->pages;
480 
481 	if (ttm->page_flags & TTM_PAGE_FLAG_SG)
482 		return;
483 
484 	for (i = 0; i < ttm->num_pages; ++i) {
485 		(*page)->mapping = NULL;
486 		(*page++)->index = 0;
487 	}
488 }
489 
490 void ttm_tt_unpopulate(struct ttm_tt *ttm)
491 {
492 	if (ttm->state == tt_unpopulated)
493 		return;
494 
495 	ttm_tt_clear_mapping(ttm);
496 	if (ttm->bdev->driver->ttm_tt_unpopulate)
497 		ttm->bdev->driver->ttm_tt_unpopulate(ttm);
498 	else
499 		ttm_pool_unpopulate(ttm);
500 }
501