ttm_tt.c revision 1.8 
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 <linux/export.h>
39#include <drm/drm_cache.h>
40#include <drm/ttm/ttm_bo_driver.h>
41#include <drm/ttm/ttm_page_alloc.h>
42#include <drm/ttm/ttm_set_memory.h>
43
44/**
45 * Allocates a ttm structure for the given BO.
46 */
47int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc)
48{
49	struct ttm_bo_device *bdev = bo->bdev;
50	uint32_t page_flags = 0;
51
52	reservation_object_assert_held(bo->resv);
53
54	if (bdev->need_dma32)
55		page_flags |= TTM_PAGE_FLAG_DMA32;
56
57	if (bdev->no_retry)
58		page_flags |= TTM_PAGE_FLAG_NO_RETRY;
59
60	switch (bo->type) {
61	case ttm_bo_type_device:
62		if (zero_alloc)
63			page_flags |= TTM_PAGE_FLAG_ZERO_ALLOC;
64		break;
65	case ttm_bo_type_kernel:
66		break;
67	case ttm_bo_type_sg:
68		page_flags |= TTM_PAGE_FLAG_SG;
69		break;
70	default:
71		bo->ttm = NULL;
72		pr_err("Illegal buffer object type\n");
73		return -EINVAL;
74	}
75
76	bo->ttm = bdev->driver->ttm_tt_create(bo, page_flags);
77	if (unlikely(bo->ttm == NULL))
78		return -ENOMEM;
79
80	return 0;
81}
82
83/**
84 * Allocates storage for pointers to the pages that back the ttm.
85 */
86static int ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
87{
88	ttm->pages = kvmalloc_array(ttm->num_pages, sizeof(void*),
89			GFP_KERNEL | __GFP_ZERO);
90	if (!ttm->pages)
91		return -ENOMEM;
92	return 0;
93}
94
95static int ttm_dma_tt_alloc_page_directory(struct ttm_dma_tt *ttm)
96{
97	ttm->ttm.pages = kvmalloc_array(ttm->ttm.num_pages,
98					  sizeof(*ttm->ttm.pages) +
99					  sizeof(*ttm->dma_address),
100					  GFP_KERNEL | __GFP_ZERO);
101	if (!ttm->ttm.pages)
102		return -ENOMEM;
103	ttm->dma_address = (void *) (ttm->ttm.pages + ttm->ttm.num_pages);
104	return 0;
105}
106
107static int ttm_sg_tt_alloc_page_directory(struct ttm_dma_tt *ttm)
108{
109	ttm->dma_address = kvmalloc_array(ttm->ttm.num_pages,
110					  sizeof(*ttm->dma_address),
111					  GFP_KERNEL | __GFP_ZERO);
112	if (!ttm->dma_address)
113		return -ENOMEM;
114	return 0;
115}
116
117static int ttm_tt_set_page_caching(struct vm_page *p,
118				   enum ttm_caching_state c_old,
119				   enum ttm_caching_state c_new)
120{
121	int ret = 0;
122
123	if (PageHighMem(p))
124		return 0;
125
126	if (c_old != tt_cached) {
127		/* p isn't in the default caching state, set it to
128		 * writeback first to free its current memtype. */
129
130		ret = ttm_set_pages_wb(p, 1);
131		if (ret)
132			return ret;
133	}
134
135	if (c_new == tt_wc)
136		ret = ttm_set_pages_wc(p, 1);
137	else if (c_new == tt_uncached)
138		ret = ttm_set_pages_uc(p, 1);
139
140	return ret;
141}
142
143/*
144 * Change caching policy for the linear kernel map
145 * for range of pages in a ttm.
146 */
147
148static int ttm_tt_set_caching(struct ttm_tt *ttm,
149			      enum ttm_caching_state c_state)
150{
151	int i, j;
152	struct vm_page *cur_page;
153	int ret;
154
155	if (ttm->caching_state == c_state)
156		return 0;
157
158	if (ttm->state == tt_unpopulated) {
159		/* Change caching but don't populate */
160		ttm->caching_state = c_state;
161		return 0;
162	}
163
164	if (ttm->caching_state == tt_cached)
165		drm_clflush_pages(ttm->pages, ttm->num_pages);
166
167	for (i = 0; i < ttm->num_pages; ++i) {
168		cur_page = ttm->pages[i];
169		if (likely(cur_page != NULL)) {
170			ret = ttm_tt_set_page_caching(cur_page,
171						      ttm->caching_state,
172						      c_state);
173			if (unlikely(ret != 0))
174				goto out_err;
175		}
176	}
177
178	ttm->caching_state = c_state;
179
180	return 0;
181
182out_err:
183	for (j = 0; j < i; ++j) {
184		cur_page = ttm->pages[j];
185		if (likely(cur_page != NULL)) {
186			(void)ttm_tt_set_page_caching(cur_page, c_state,
187						      ttm->caching_state);
188		}
189	}
190
191	return ret;
192}
193
194int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement)
195{
196	enum ttm_caching_state state;
197
198	if (placement & TTM_PL_FLAG_WC)
199		state = tt_wc;
200	else if (placement & TTM_PL_FLAG_UNCACHED)
201		state = tt_uncached;
202	else
203		state = tt_cached;
204
205	return ttm_tt_set_caching(ttm, state);
206}
207EXPORT_SYMBOL(ttm_tt_set_placement_caching);
208
209void ttm_tt_destroy(struct ttm_tt *ttm)
210{
211	if (ttm == NULL)
212		return;
213
214	ttm_tt_unbind(ttm);
215
216	if (ttm->state == tt_unbound)
217		ttm_tt_unpopulate(ttm);
218
219	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP) &&
220	    ttm->swap_storage)
221		uao_detach(ttm->swap_storage);
222
223	ttm->swap_storage = NULL;
224	ttm->func->destroy(ttm);
225}
226
227void ttm_tt_init_fields(struct ttm_tt *ttm, 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
239int 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}
251EXPORT_SYMBOL(ttm_tt_init);
252
253void ttm_tt_fini(struct ttm_tt *ttm)
254{
255	kvfree(ttm->pages);
256	ttm->pages = NULL;
257}
258EXPORT_SYMBOL(ttm_tt_fini);
259
260int 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
274	ttm_dma->segs =  mallocarray(ttm->num_pages,
275	    sizeof(bus_dma_segment_t), M_DRM, M_WAITOK | M_ZERO);
276
277	ttm_dma->dmat = bo->bdev->dmat;
278
279	if (bus_dmamap_create(ttm_dma->dmat, ttm->num_pages << PAGE_SHIFT,
280	    ttm->num_pages, ttm->num_pages << PAGE_SHIFT, 0, BUS_DMA_WAITOK,
281	    &ttm_dma->map)) {
282		free(ttm_dma->segs, M_DRM, 0);
283		ttm_tt_destroy(ttm);
284		pr_err("Failed allocating page table\n");
285		return -ENOMEM;
286	}
287
288	return 0;
289}
290EXPORT_SYMBOL(ttm_dma_tt_init);
291
292int ttm_sg_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_buffer_object *bo,
293		   uint32_t page_flags)
294{
295	struct ttm_tt *ttm = &ttm_dma->ttm;
296	int ret;
297
298	ttm_tt_init_fields(ttm, bo, page_flags);
299
300	INIT_LIST_HEAD(&ttm_dma->pages_list);
301	if (page_flags & TTM_PAGE_FLAG_SG)
302		ret = ttm_sg_tt_alloc_page_directory(ttm_dma);
303	else
304		ret = ttm_dma_tt_alloc_page_directory(ttm_dma);
305	if (ret) {
306		ttm_tt_destroy(ttm);
307		pr_err("Failed allocating page table\n");
308		return -ENOMEM;
309	}
310
311	ttm_dma->segs =  mallocarray(ttm->num_pages,
312	    sizeof(bus_dma_segment_t), M_DRM, M_WAITOK | M_ZERO);
313
314	ttm_dma->dmat = bo->bdev->dmat;
315
316	if (bus_dmamap_create(ttm_dma->dmat, ttm->num_pages << PAGE_SHIFT,
317	    ttm->num_pages, ttm->num_pages << PAGE_SHIFT, 0, BUS_DMA_WAITOK,
318	    &ttm_dma->map)) {
319		free(ttm_dma->segs, M_DRM, 0);
320		ttm_tt_destroy(ttm);
321		pr_err("Failed allocating page table\n");
322		return -ENOMEM;
323	}
324
325	return 0;
326}
327EXPORT_SYMBOL(ttm_sg_tt_init);
328
329void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma)
330{
331	struct ttm_tt *ttm = &ttm_dma->ttm;
332
333	if (ttm->pages)
334		kvfree(ttm->pages);
335	else
336		kvfree(ttm_dma->dma_address);
337	ttm->pages = NULL;
338	ttm_dma->dma_address = NULL;
339
340	bus_dmamap_destroy(ttm_dma->dmat, ttm_dma->map);
341	free(ttm_dma->segs, M_DRM, 0);
342}
343EXPORT_SYMBOL(ttm_dma_tt_fini);
344
345void ttm_tt_unbind(struct ttm_tt *ttm)
346{
347	int ret;
348
349	if (ttm->state == tt_bound) {
350		ret = ttm->func->unbind(ttm);
351		BUG_ON(ret);
352		ttm->state = tt_unbound;
353	}
354}
355
356int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem,
357		struct ttm_operation_ctx *ctx)
358{
359	int ret = 0;
360
361	if (!ttm)
362		return -EINVAL;
363
364	if (ttm->state == tt_bound)
365		return 0;
366
367	ret = ttm_tt_populate(ttm, ctx);
368	if (ret)
369		return ret;
370
371	ret = ttm->func->bind(ttm, bo_mem);
372	if (unlikely(ret != 0))
373		return ret;
374
375	ttm->state = tt_bound;
376
377	return 0;
378}
379EXPORT_SYMBOL(ttm_tt_bind);
380
381int ttm_tt_swapin(struct ttm_tt *ttm)
382{
383	struct uvm_object *swap_storage;
384	struct vm_page *from_page;
385	struct vm_page *to_page;
386	struct pglist plist;
387	int i;
388	int ret = -ENOMEM;
389
390	swap_storage = ttm->swap_storage;
391	BUG_ON(swap_storage == NULL);
392
393	TAILQ_INIT(&plist);
394	if (uvm_objwire(swap_storage, 0, ttm->num_pages << PAGE_SHIFT, &plist))
395		goto out_err;
396
397	from_page = TAILQ_FIRST(&plist);
398	for (i = 0; i < ttm->num_pages; ++i) {
399		to_page = ttm->pages[i];
400		if (unlikely(to_page == NULL))
401			goto out_err;
402
403		uvm_pagecopy(from_page, to_page);
404		from_page = TAILQ_NEXT(from_page, pageq);
405	}
406
407	uvm_objunwire(swap_storage, 0, ttm->num_pages << PAGE_SHIFT);
408
409	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP))
410		uao_detach(swap_storage);
411	ttm->swap_storage = NULL;
412	ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
413
414	return 0;
415out_err:
416	return ret;
417}
418
419int ttm_tt_swapout(struct ttm_tt *ttm, struct uvm_object *persistent_swap_storage)
420{
421	struct uvm_object *swap_storage;
422	struct vm_page *from_page;
423	struct vm_page *to_page;
424	struct pglist plist;
425	int i;
426	int ret = -ENOMEM;
427
428	BUG_ON(ttm->state != tt_unbound && ttm->state != tt_unpopulated);
429	BUG_ON(ttm->caching_state != tt_cached);
430
431	if (!persistent_swap_storage) {
432		swap_storage = uao_create(ttm->num_pages << PAGE_SHIFT, 0);
433#ifdef notyet
434		if (IS_ERR(swap_storage)) {
435			pr_err("Failed allocating swap storage\n");
436			return PTR_ERR(swap_storage);
437		}
438#endif
439	} else {
440		swap_storage = persistent_swap_storage;
441	}
442
443	TAILQ_INIT(&plist);
444	if (uvm_objwire(swap_storage, 0, ttm->num_pages << PAGE_SHIFT, &plist))
445		goto out_err;
446
447	to_page = TAILQ_FIRST(&plist);
448	for (i = 0; i < ttm->num_pages; ++i) {
449		from_page = ttm->pages[i];
450		if (unlikely(from_page == NULL))
451			continue;
452
453		uvm_pagecopy(from_page, to_page);
454#ifdef notyet
455		set_page_dirty(to_page);
456		mark_page_accessed(to_page);
457#endif
458		to_page = TAILQ_NEXT(to_page, pageq);
459	}
460
461	uvm_objunwire(swap_storage, 0, ttm->num_pages << PAGE_SHIFT);
462
463	ttm->bdev->driver->ttm_tt_unpopulate(ttm);
464	ttm->swap_storage = swap_storage;
465	ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
466	if (persistent_swap_storage)
467		ttm->page_flags |= TTM_PAGE_FLAG_PERSISTENT_SWAP;
468
469	return 0;
470out_err:
471	if (!persistent_swap_storage)
472		uao_detach(swap_storage);
473
474	return ret;
475}
476
477static void ttm_tt_add_mapping(struct ttm_tt *ttm)
478{
479#ifdef __linux__
480	pgoff_t i;
481
482	if (ttm->page_flags & TTM_PAGE_FLAG_SG)
483		return;
484
485	for (i = 0; i < ttm->num_pages; ++i)
486		ttm->pages[i]->mapping = ttm->bdev->dev_mapping;
487#endif
488}
489
490int ttm_tt_populate(struct ttm_tt *ttm, struct ttm_operation_ctx *ctx)
491{
492	int ret;
493
494	if (ttm->state != tt_unpopulated)
495		return 0;
496
497	if (ttm->bdev->driver->ttm_tt_populate)
498		ret = ttm->bdev->driver->ttm_tt_populate(ttm, ctx);
499	else
500		ret = ttm_pool_populate(ttm, ctx);
501	if (!ret)
502		ttm_tt_add_mapping(ttm);
503	return ret;
504}
505
506static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
507{
508	int i;
509	struct vm_page *page;
510
511	if (ttm->page_flags & TTM_PAGE_FLAG_SG)
512		return;
513
514	for (i = 0; i < ttm->num_pages; ++i) {
515		page = ttm->pages[i];
516		if (unlikely(page == NULL))
517			continue;
518		pmap_page_protect(page, PROT_NONE);
519	}
520}
521
522void ttm_tt_unpopulate(struct ttm_tt *ttm)
523{
524	if (ttm->state == tt_unpopulated)
525		return;
526
527	ttm_tt_clear_mapping(ttm);
528	if (ttm->bdev->driver->ttm_tt_unpopulate)
529		ttm->bdev->driver->ttm_tt_unpopulate(ttm);
530	else
531		ttm_pool_unpopulate(ttm);
532}
533