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 */
46int 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 (bo->ttm)
54		return 0;
55
56	if (bdev->need_dma32)
57		page_flags |= TTM_PAGE_FLAG_DMA32;
58
59	if (bdev->no_retry)
60		page_flags |= TTM_PAGE_FLAG_NO_RETRY;
61
62	switch (bo->type) {
63	case ttm_bo_type_device:
64		if (zero_alloc)
65			page_flags |= TTM_PAGE_FLAG_ZERO_ALLOC;
66		break;
67	case ttm_bo_type_kernel:
68		break;
69	case ttm_bo_type_sg:
70		page_flags |= TTM_PAGE_FLAG_SG;
71		break;
72	default:
73		pr_err("Illegal buffer object type\n");
74		return -EINVAL;
75	}
76
77	bo->ttm = bdev->driver->ttm_tt_create(bo, page_flags);
78	if (unlikely(bo->ttm == NULL))
79		return -ENOMEM;
80
81	return 0;
82}
83
84/**
85 * Allocates storage for pointers to the pages that back the ttm.
86 */
87static int ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
88{
89	ttm->pages = kvmalloc_array(ttm->num_pages, sizeof(void*),
90			GFP_KERNEL | __GFP_ZERO);
91	if (!ttm->pages)
92		return -ENOMEM;
93	return 0;
94}
95
96static int ttm_dma_tt_alloc_page_directory(struct ttm_dma_tt *ttm)
97{
98	ttm->ttm.pages = kvmalloc_array(ttm->ttm.num_pages,
99					  sizeof(*ttm->ttm.pages) +
100					  sizeof(*ttm->dma_address),
101					  GFP_KERNEL | __GFP_ZERO);
102	if (!ttm->ttm.pages)
103		return -ENOMEM;
104	ttm->dma_address = (void *) (ttm->ttm.pages + ttm->ttm.num_pages);
105	return 0;
106}
107
108static int ttm_sg_tt_alloc_page_directory(struct ttm_dma_tt *ttm)
109{
110	ttm->dma_address = kvmalloc_array(ttm->ttm.num_pages,
111					  sizeof(*ttm->dma_address),
112					  GFP_KERNEL | __GFP_ZERO);
113	if (!ttm->dma_address)
114		return -ENOMEM;
115	return 0;
116}
117
118static int ttm_tt_set_page_caching(struct page *p,
119				   enum ttm_caching_state c_old,
120				   enum ttm_caching_state c_new)
121{
122	int ret = 0;
123
124	if (PageHighMem(p))
125		return 0;
126
127	if (c_old != tt_cached) {
128		/* p isn't in the default caching state, set it to
129		 * writeback first to free its current memtype. */
130
131		ret = ttm_set_pages_wb(p, 1);
132		if (ret)
133			return ret;
134	}
135
136	if (c_new == tt_wc)
137		ret = ttm_set_pages_wc(p, 1);
138	else if (c_new == tt_uncached)
139		ret = ttm_set_pages_uc(p, 1);
140
141	return ret;
142}
143
144/*
145 * Change caching policy for the linear kernel map
146 * for range of pages in a ttm.
147 */
148
149static int ttm_tt_set_caching(struct ttm_tt *ttm,
150			      enum ttm_caching_state c_state)
151{
152	int i, j;
153	struct page *cur_page;
154	int ret;
155
156	if (ttm->caching_state == c_state)
157		return 0;
158
159	if (!ttm_tt_is_populated(ttm)) {
160		/* Change caching but don't populate */
161		ttm->caching_state = c_state;
162		return 0;
163	}
164
165	if (ttm->caching_state == tt_cached)
166		drm_clflush_pages(ttm->pages, ttm->num_pages);
167
168	for (i = 0; i < ttm->num_pages; ++i) {
169		cur_page = ttm->pages[i];
170		if (likely(cur_page != NULL)) {
171			ret = ttm_tt_set_page_caching(cur_page,
172						      ttm->caching_state,
173						      c_state);
174			if (unlikely(ret != 0))
175				goto out_err;
176		}
177	}
178
179	ttm->caching_state = c_state;
180
181	return 0;
182
183out_err:
184	for (j = 0; j < i; ++j) {
185		cur_page = ttm->pages[j];
186		if (likely(cur_page != NULL)) {
187			(void)ttm_tt_set_page_caching(cur_page, c_state,
188						      ttm->caching_state);
189		}
190	}
191
192	return ret;
193}
194
195int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement)
196{
197	enum ttm_caching_state state;
198
199	if (placement & TTM_PL_FLAG_WC)
200		state = tt_wc;
201	else if (placement & TTM_PL_FLAG_UNCACHED)
202		state = tt_uncached;
203	else
204		state = tt_cached;
205
206	return ttm_tt_set_caching(ttm, state);
207}
208EXPORT_SYMBOL(ttm_tt_set_placement_caching);
209
210void ttm_tt_destroy_common(struct ttm_bo_device *bdev, struct ttm_tt *ttm)
211{
212	ttm_tt_unpopulate(bdev, ttm);
213
214	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP) &&
215	    ttm->swap_storage)
216		fput(ttm->swap_storage);
217
218	ttm->swap_storage = NULL;
219}
220EXPORT_SYMBOL(ttm_tt_destroy_common);
221
222void ttm_tt_destroy(struct ttm_bo_device *bdev, struct ttm_tt *ttm)
223{
224	bdev->driver->ttm_tt_destroy(bdev, ttm);
225}
226
227static void ttm_tt_init_fields(struct ttm_tt *ttm,
228			       struct ttm_buffer_object *bo,
229			       uint32_t page_flags)
230{
231	ttm->num_pages = bo->num_pages;
232	ttm->caching_state = tt_cached;
233	ttm->page_flags = page_flags;
234	ttm_tt_set_unpopulated(ttm);
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		pr_err("Failed allocating page table\n");
246		return -ENOMEM;
247	}
248	return 0;
249}
250EXPORT_SYMBOL(ttm_tt_init);
251
252void ttm_tt_fini(struct ttm_tt *ttm)
253{
254	kvfree(ttm->pages);
255	ttm->pages = NULL;
256}
257EXPORT_SYMBOL(ttm_tt_fini);
258
259int 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}
273EXPORT_SYMBOL(ttm_dma_tt_init);
274
275int 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}
294EXPORT_SYMBOL(ttm_sg_tt_init);
295
296void 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}
307EXPORT_SYMBOL(ttm_dma_tt_fini);
308
309int ttm_tt_swapin(struct ttm_tt *ttm)
310{
311	struct address_space *swap_space;
312	struct file *swap_storage;
313	struct page *from_page;
314	struct page *to_page;
315	int i;
316	int ret = -ENOMEM;
317
318	swap_storage = ttm->swap_storage;
319	BUG_ON(swap_storage == NULL);
320
321	swap_space = swap_storage->f_mapping;
322
323	for (i = 0; i < ttm->num_pages; ++i) {
324		gfp_t gfp_mask = mapping_gfp_mask(swap_space);
325
326		gfp_mask |= (ttm->page_flags & TTM_PAGE_FLAG_NO_RETRY ? __GFP_RETRY_MAYFAIL : 0);
327		from_page = shmem_read_mapping_page_gfp(swap_space, i, gfp_mask);
328
329		if (IS_ERR(from_page)) {
330			ret = PTR_ERR(from_page);
331			goto out_err;
332		}
333		to_page = ttm->pages[i];
334		if (unlikely(to_page == NULL))
335			goto out_err;
336
337		copy_highpage(to_page, from_page);
338		put_page(from_page);
339	}
340
341	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP))
342		fput(swap_storage);
343	ttm->swap_storage = NULL;
344	ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
345
346	return 0;
347out_err:
348	return ret;
349}
350
351int ttm_tt_swapout(struct ttm_bo_device *bdev,
352		   struct ttm_tt *ttm, struct file *persistent_swap_storage)
353{
354	struct address_space *swap_space;
355	struct file *swap_storage;
356	struct page *from_page;
357	struct page *to_page;
358	int i;
359	int ret = -ENOMEM;
360
361	BUG_ON(ttm->caching_state != tt_cached);
362
363	if (!persistent_swap_storage) {
364		swap_storage = shmem_file_setup("ttm swap",
365						ttm->num_pages << PAGE_SHIFT,
366						0);
367		if (IS_ERR(swap_storage)) {
368			pr_err("Failed allocating swap storage\n");
369			return PTR_ERR(swap_storage);
370		}
371	} else {
372		swap_storage = persistent_swap_storage;
373	}
374
375	swap_space = swap_storage->f_mapping;
376
377	for (i = 0; i < ttm->num_pages; ++i) {
378		gfp_t gfp_mask = mapping_gfp_mask(swap_space);
379
380		gfp_mask |= (ttm->page_flags & TTM_PAGE_FLAG_NO_RETRY ? __GFP_RETRY_MAYFAIL : 0);
381
382		from_page = ttm->pages[i];
383		if (unlikely(from_page == NULL))
384			continue;
385
386		to_page = shmem_read_mapping_page_gfp(swap_space, i, gfp_mask);
387		if (IS_ERR(to_page)) {
388			ret = PTR_ERR(to_page);
389			goto out_err;
390		}
391		copy_highpage(to_page, from_page);
392		set_page_dirty(to_page);
393		mark_page_accessed(to_page);
394		put_page(to_page);
395	}
396
397	ttm_tt_unpopulate(bdev, ttm);
398	ttm->swap_storage = swap_storage;
399	ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
400	if (persistent_swap_storage)
401		ttm->page_flags |= TTM_PAGE_FLAG_PERSISTENT_SWAP;
402
403	return 0;
404out_err:
405	if (!persistent_swap_storage)
406		fput(swap_storage);
407
408	return ret;
409}
410
411static void ttm_tt_add_mapping(struct ttm_bo_device *bdev, struct ttm_tt *ttm)
412{
413	pgoff_t i;
414
415	if (ttm->page_flags & TTM_PAGE_FLAG_SG)
416		return;
417
418	for (i = 0; i < ttm->num_pages; ++i)
419		ttm->pages[i]->mapping = bdev->dev_mapping;
420}
421
422int ttm_tt_populate(struct ttm_bo_device *bdev,
423		    struct ttm_tt *ttm, struct ttm_operation_ctx *ctx)
424{
425	int ret;
426
427	if (!ttm)
428		return -EINVAL;
429
430	if (ttm_tt_is_populated(ttm))
431		return 0;
432
433	if (bdev->driver->ttm_tt_populate)
434		ret = bdev->driver->ttm_tt_populate(bdev, ttm, ctx);
435	else
436		ret = ttm_pool_populate(ttm, ctx);
437	if (!ret)
438		ttm_tt_add_mapping(bdev, ttm);
439	return ret;
440}
441EXPORT_SYMBOL(ttm_tt_populate);
442
443static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
444{
445	pgoff_t i;
446	struct page **page = ttm->pages;
447
448	if (ttm->page_flags & TTM_PAGE_FLAG_SG)
449		return;
450
451	for (i = 0; i < ttm->num_pages; ++i) {
452		(*page)->mapping = NULL;
453		(*page++)->index = 0;
454	}
455}
456
457void ttm_tt_unpopulate(struct ttm_bo_device *bdev,
458		       struct ttm_tt *ttm)
459{
460	if (!ttm_tt_is_populated(ttm))
461		return;
462
463	ttm_tt_clear_mapping(ttm);
464	if (bdev->driver->ttm_tt_unpopulate)
465		bdev->driver->ttm_tt_unpopulate(bdev, ttm);
466	else
467		ttm_pool_unpopulate(ttm);
468}
469