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1/**************************************************************************
2 *
3 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24 * USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27/*
28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29 */
30
31#define pr_fmt(fmt) "[TTM] " fmt
32
33#include <linux/sched.h>
34#include <linux/highmem.h>
35#include <linux/pagemap.h>
36#include <linux/shmem_fs.h>
37#include <linux/file.h>
38#include <linux/swap.h>
39#include <linux/slab.h>
40#include <linux/export.h>
41#include <drm/drm_cache.h>
42#include <drm/drm_mem_util.h>
43#include <drm/ttm/ttm_module.h>
44#include <drm/ttm/ttm_bo_driver.h>
45#include <drm/ttm/ttm_placement.h>
46#include <drm/ttm/ttm_page_alloc.h>
47
48/**
49 * Allocates storage for pointers to the pages that back the ttm.
50 */
51static void ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
52{
53 ttm->pages = drm_calloc_large(ttm->num_pages, sizeof(void*));
54}
55
56static void ttm_dma_tt_alloc_page_directory(struct ttm_dma_tt *ttm)
57{
58 ttm->ttm.pages = drm_calloc_large(ttm->ttm.num_pages,
59 sizeof(*ttm->ttm.pages) +
60 sizeof(*ttm->dma_address));
61 ttm->dma_address = (void *) (ttm->ttm.pages + ttm->ttm.num_pages);
62}
63
64#ifdef CONFIG_X86
65static inline int ttm_tt_set_page_caching(struct page *p,
66 enum ttm_caching_state c_old,
67 enum ttm_caching_state c_new)
68{
69 int ret = 0;
70
71 if (PageHighMem(p))
72 return 0;
73
74 if (c_old != tt_cached) {
75 /* p isn't in the default caching state, set it to
76 * writeback first to free its current memtype. */
77
78 ret = set_pages_wb(p, 1);
79 if (ret)
80 return ret;
81 }
82
83 if (c_new == tt_wc)
84 ret = set_memory_wc((unsigned long) page_address(p), 1);
85 else if (c_new == tt_uncached)
86 ret = set_pages_uc(p, 1);
87
88 return ret;
89}
90#else /* CONFIG_X86 */
91static inline int ttm_tt_set_page_caching(struct page *p,
92 enum ttm_caching_state c_old,
93 enum ttm_caching_state c_new)
94{
95 return 0;
96}
97#endif /* CONFIG_X86 */
98
99/*
100 * Change caching policy for the linear kernel map
101 * for range of pages in a ttm.
102 */
103
104static int ttm_tt_set_caching(struct ttm_tt *ttm,
105 enum ttm_caching_state c_state)
106{
107 int i, j;
108 struct page *cur_page;
109 int ret;
110
111 if (ttm->caching_state == c_state)
112 return 0;
113
114 if (ttm->state == tt_unpopulated) {
115 /* Change caching but don't populate */
116 ttm->caching_state = c_state;
117 return 0;
118 }
119
120 if (ttm->caching_state == tt_cached)
121 drm_clflush_pages(ttm->pages, ttm->num_pages);
122
123 for (i = 0; i < ttm->num_pages; ++i) {
124 cur_page = ttm->pages[i];
125 if (likely(cur_page != NULL)) {
126 ret = ttm_tt_set_page_caching(cur_page,
127 ttm->caching_state,
128 c_state);
129 if (unlikely(ret != 0))
130 goto out_err;
131 }
132 }
133
134 ttm->caching_state = c_state;
135
136 return 0;
137
138out_err:
139 for (j = 0; j < i; ++j) {
140 cur_page = ttm->pages[j];
141 if (likely(cur_page != NULL)) {
142 (void)ttm_tt_set_page_caching(cur_page, c_state,
143 ttm->caching_state);
144 }
145 }
146
147 return ret;
148}
149
150int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement)
151{
152 enum ttm_caching_state state;
153
154 if (placement & TTM_PL_FLAG_WC)
155 state = tt_wc;
156 else if (placement & TTM_PL_FLAG_UNCACHED)
157 state = tt_uncached;
158 else
159 state = tt_cached;
160
161 return ttm_tt_set_caching(ttm, state);
162}
163EXPORT_SYMBOL(ttm_tt_set_placement_caching);
164
165void ttm_tt_destroy(struct ttm_tt *ttm)
166{
167 if (ttm == NULL)
168 return;
169
170 ttm_tt_unbind(ttm);
171
172 if (ttm->state == tt_unbound)
173 ttm_tt_unpopulate(ttm);
174
175 if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP) &&
176 ttm->swap_storage)
177 fput(ttm->swap_storage);
178
179 ttm->swap_storage = NULL;
180 ttm->func->destroy(ttm);
181}
182
183int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev,
184 unsigned long size, uint32_t page_flags,
185 struct page *dummy_read_page)
186{
187 ttm->bdev = bdev;
188 ttm->glob = bdev->glob;
189 ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
190 ttm->caching_state = tt_cached;
191 ttm->page_flags = page_flags;
192 ttm->dummy_read_page = dummy_read_page;
193 ttm->state = tt_unpopulated;
194 ttm->swap_storage = NULL;
195
196 ttm_tt_alloc_page_directory(ttm);
197 if (!ttm->pages) {
198 ttm_tt_destroy(ttm);
199 pr_err("Failed allocating page table\n");
200 return -ENOMEM;
201 }
202 return 0;
203}
204EXPORT_SYMBOL(ttm_tt_init);
205
206void ttm_tt_fini(struct ttm_tt *ttm)
207{
208 drm_free_large(ttm->pages);
209 ttm->pages = NULL;
210}
211EXPORT_SYMBOL(ttm_tt_fini);
212
213int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev,
214 unsigned long size, uint32_t page_flags,
215 struct page *dummy_read_page)
216{
217 struct ttm_tt *ttm = &ttm_dma->ttm;
218
219 ttm->bdev = bdev;
220 ttm->glob = bdev->glob;
221 ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
222 ttm->caching_state = tt_cached;
223 ttm->page_flags = page_flags;
224 ttm->dummy_read_page = dummy_read_page;
225 ttm->state = tt_unpopulated;
226 ttm->swap_storage = NULL;
227
228 INIT_LIST_HEAD(&ttm_dma->pages_list);
229 ttm_dma_tt_alloc_page_directory(ttm_dma);
230 if (!ttm->pages) {
231 ttm_tt_destroy(ttm);
232 pr_err("Failed allocating page table\n");
233 return -ENOMEM;
234 }
235 return 0;
236}
237EXPORT_SYMBOL(ttm_dma_tt_init);
238
239void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma)
240{
241 struct ttm_tt *ttm = &ttm_dma->ttm;
242
243 drm_free_large(ttm->pages);
244 ttm->pages = NULL;
245 ttm_dma->dma_address = NULL;
246}
247EXPORT_SYMBOL(ttm_dma_tt_fini);
248
249void ttm_tt_unbind(struct ttm_tt *ttm)
250{
251 int ret;
252
253 if (ttm->state == tt_bound) {
254 ret = ttm->func->unbind(ttm);
255 BUG_ON(ret);
256 ttm->state = tt_unbound;
257 }
258}
259
260int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem)
261{
262 int ret = 0;
263
264 if (!ttm)
265 return -EINVAL;
266
267 if (ttm->state == tt_bound)
268 return 0;
269
270 ret = ttm->bdev->driver->ttm_tt_populate(ttm);
271 if (ret)
272 return ret;
273
274 ret = ttm->func->bind(ttm, bo_mem);
275 if (unlikely(ret != 0))
276 return ret;
277
278 ttm->state = tt_bound;
279
280 return 0;
281}
282EXPORT_SYMBOL(ttm_tt_bind);
283
284int ttm_tt_swapin(struct ttm_tt *ttm)
285{
286 struct address_space *swap_space;
287 struct file *swap_storage;
288 struct page *from_page;
289 struct page *to_page;
290 int i;
291 int ret = -ENOMEM;
292
293 swap_storage = ttm->swap_storage;
294 BUG_ON(swap_storage == NULL);
295
296 swap_space = swap_storage->f_mapping;
297
298 for (i = 0; i < ttm->num_pages; ++i) {
299 from_page = shmem_read_mapping_page(swap_space, i);
300 if (IS_ERR(from_page)) {
301 ret = PTR_ERR(from_page);
302 goto out_err;
303 }
304 to_page = ttm->pages[i];
305 if (unlikely(to_page == NULL))
306 goto out_err;
307
308 copy_highpage(to_page, from_page);
309 put_page(from_page);
310 }
311
312 if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP))
313 fput(swap_storage);
314 ttm->swap_storage = NULL;
315 ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
316
317 return 0;
318out_err:
319 return ret;
320}
321
322int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistent_swap_storage)
323{
324 struct address_space *swap_space;
325 struct file *swap_storage;
326 struct page *from_page;
327 struct page *to_page;
328 int i;
329 int ret = -ENOMEM;
330
331 BUG_ON(ttm->state != tt_unbound && ttm->state != tt_unpopulated);
332 BUG_ON(ttm->caching_state != tt_cached);
333
334 if (!persistent_swap_storage) {
335 swap_storage = shmem_file_setup("ttm swap",
336 ttm->num_pages << PAGE_SHIFT,
337 0);
338 if (IS_ERR(swap_storage)) {
339 pr_err("Failed allocating swap storage\n");
340 return PTR_ERR(swap_storage);
341 }
342 } else
343 swap_storage = persistent_swap_storage;
344
345 swap_space = swap_storage->f_mapping;
346
347 for (i = 0; i < ttm->num_pages; ++i) {
348 from_page = ttm->pages[i];
349 if (unlikely(from_page == NULL))
350 continue;
351 to_page = shmem_read_mapping_page(swap_space, i);
352 if (IS_ERR(to_page)) {
353 ret = PTR_ERR(to_page);
354 goto out_err;
355 }
356 copy_highpage(to_page, from_page);
357 set_page_dirty(to_page);
358 mark_page_accessed(to_page);
359 put_page(to_page);
360 }
361
362 ttm_tt_unpopulate(ttm);
363 ttm->swap_storage = swap_storage;
364 ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
365 if (persistent_swap_storage)
366 ttm->page_flags |= TTM_PAGE_FLAG_PERSISTENT_SWAP;
367
368 return 0;
369out_err:
370 if (!persistent_swap_storage)
371 fput(swap_storage);
372
373 return ret;
374}
375
376static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
377{
378 pgoff_t i;
379 struct page **page = ttm->pages;
380
381 if (ttm->page_flags & TTM_PAGE_FLAG_SG)
382 return;
383
384 for (i = 0; i < ttm->num_pages; ++i) {
385 (*page)->mapping = NULL;
386 (*page++)->index = 0;
387 }
388}
389
390void ttm_tt_unpopulate(struct ttm_tt *ttm)
391{
392 if (ttm->state == tt_unpopulated)
393 return;
394
395 ttm_tt_clear_mapping(ttm);
396 ttm->bdev->driver->ttm_tt_unpopulate(ttm);
397}
1/**************************************************************************
2 *
3 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24 * USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27/*
28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29 */
30
31#define pr_fmt(fmt) "[TTM] " fmt
32
33#include <linux/sched.h>
34#include <linux/highmem.h>
35#include <linux/pagemap.h>
36#include <linux/shmem_fs.h>
37#include <linux/file.h>
38#include <linux/swap.h>
39#include <linux/slab.h>
40#include <linux/export.h>
41#include <drm/drm_cache.h>
42#include <drm/drm_mem_util.h>
43#include <drm/ttm/ttm_module.h>
44#include <drm/ttm/ttm_bo_driver.h>
45#include <drm/ttm/ttm_placement.h>
46#include <drm/ttm/ttm_page_alloc.h>
47
48/**
49 * Allocates storage for pointers to the pages that back the ttm.
50 */
51static void ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
52{
53 ttm->pages = drm_calloc_large(ttm->num_pages, sizeof(void*));
54}
55
56static void ttm_dma_tt_alloc_page_directory(struct ttm_dma_tt *ttm)
57{
58 ttm->ttm.pages = drm_calloc_large(ttm->ttm.num_pages, sizeof(void*));
59 ttm->dma_address = drm_calloc_large(ttm->ttm.num_pages,
60 sizeof(*ttm->dma_address));
61}
62
63#ifdef CONFIG_X86
64static inline int ttm_tt_set_page_caching(struct page *p,
65 enum ttm_caching_state c_old,
66 enum ttm_caching_state c_new)
67{
68 int ret = 0;
69
70 if (PageHighMem(p))
71 return 0;
72
73 if (c_old != tt_cached) {
74 /* p isn't in the default caching state, set it to
75 * writeback first to free its current memtype. */
76
77 ret = set_pages_wb(p, 1);
78 if (ret)
79 return ret;
80 }
81
82 if (c_new == tt_wc)
83 ret = set_memory_wc((unsigned long) page_address(p), 1);
84 else if (c_new == tt_uncached)
85 ret = set_pages_uc(p, 1);
86
87 return ret;
88}
89#else /* CONFIG_X86 */
90static inline int ttm_tt_set_page_caching(struct page *p,
91 enum ttm_caching_state c_old,
92 enum ttm_caching_state c_new)
93{
94 return 0;
95}
96#endif /* CONFIG_X86 */
97
98/*
99 * Change caching policy for the linear kernel map
100 * for range of pages in a ttm.
101 */
102
103static int ttm_tt_set_caching(struct ttm_tt *ttm,
104 enum ttm_caching_state c_state)
105{
106 int i, j;
107 struct page *cur_page;
108 int ret;
109
110 if (ttm->caching_state == c_state)
111 return 0;
112
113 if (ttm->state == tt_unpopulated) {
114 /* Change caching but don't populate */
115 ttm->caching_state = c_state;
116 return 0;
117 }
118
119 if (ttm->caching_state == tt_cached)
120 drm_clflush_pages(ttm->pages, ttm->num_pages);
121
122 for (i = 0; i < ttm->num_pages; ++i) {
123 cur_page = ttm->pages[i];
124 if (likely(cur_page != NULL)) {
125 ret = ttm_tt_set_page_caching(cur_page,
126 ttm->caching_state,
127 c_state);
128 if (unlikely(ret != 0))
129 goto out_err;
130 }
131 }
132
133 ttm->caching_state = c_state;
134
135 return 0;
136
137out_err:
138 for (j = 0; j < i; ++j) {
139 cur_page = ttm->pages[j];
140 if (likely(cur_page != NULL)) {
141 (void)ttm_tt_set_page_caching(cur_page, c_state,
142 ttm->caching_state);
143 }
144 }
145
146 return ret;
147}
148
149int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement)
150{
151 enum ttm_caching_state state;
152
153 if (placement & TTM_PL_FLAG_WC)
154 state = tt_wc;
155 else if (placement & TTM_PL_FLAG_UNCACHED)
156 state = tt_uncached;
157 else
158 state = tt_cached;
159
160 return ttm_tt_set_caching(ttm, state);
161}
162EXPORT_SYMBOL(ttm_tt_set_placement_caching);
163
164void ttm_tt_destroy(struct ttm_tt *ttm)
165{
166 if (unlikely(ttm == NULL))
167 return;
168
169 if (ttm->state == tt_bound) {
170 ttm_tt_unbind(ttm);
171 }
172
173 if (ttm->state == tt_unbound)
174 ttm_tt_unpopulate(ttm);
175
176 if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP) &&
177 ttm->swap_storage)
178 fput(ttm->swap_storage);
179
180 ttm->swap_storage = NULL;
181 ttm->func->destroy(ttm);
182}
183
184int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev,
185 unsigned long size, uint32_t page_flags,
186 struct page *dummy_read_page)
187{
188 ttm->bdev = bdev;
189 ttm->glob = bdev->glob;
190 ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
191 ttm->caching_state = tt_cached;
192 ttm->page_flags = page_flags;
193 ttm->dummy_read_page = dummy_read_page;
194 ttm->state = tt_unpopulated;
195 ttm->swap_storage = NULL;
196
197 ttm_tt_alloc_page_directory(ttm);
198 if (!ttm->pages) {
199 ttm_tt_destroy(ttm);
200 pr_err("Failed allocating page table\n");
201 return -ENOMEM;
202 }
203 return 0;
204}
205EXPORT_SYMBOL(ttm_tt_init);
206
207void ttm_tt_fini(struct ttm_tt *ttm)
208{
209 drm_free_large(ttm->pages);
210 ttm->pages = NULL;
211}
212EXPORT_SYMBOL(ttm_tt_fini);
213
214int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev,
215 unsigned long size, uint32_t page_flags,
216 struct page *dummy_read_page)
217{
218 struct ttm_tt *ttm = &ttm_dma->ttm;
219
220 ttm->bdev = bdev;
221 ttm->glob = bdev->glob;
222 ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
223 ttm->caching_state = tt_cached;
224 ttm->page_flags = page_flags;
225 ttm->dummy_read_page = dummy_read_page;
226 ttm->state = tt_unpopulated;
227 ttm->swap_storage = NULL;
228
229 INIT_LIST_HEAD(&ttm_dma->pages_list);
230 ttm_dma_tt_alloc_page_directory(ttm_dma);
231 if (!ttm->pages || !ttm_dma->dma_address) {
232 ttm_tt_destroy(ttm);
233 pr_err("Failed allocating page table\n");
234 return -ENOMEM;
235 }
236 return 0;
237}
238EXPORT_SYMBOL(ttm_dma_tt_init);
239
240void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma)
241{
242 struct ttm_tt *ttm = &ttm_dma->ttm;
243
244 drm_free_large(ttm->pages);
245 ttm->pages = NULL;
246 drm_free_large(ttm_dma->dma_address);
247 ttm_dma->dma_address = NULL;
248}
249EXPORT_SYMBOL(ttm_dma_tt_fini);
250
251void ttm_tt_unbind(struct ttm_tt *ttm)
252{
253 int ret;
254
255 if (ttm->state == tt_bound) {
256 ret = ttm->func->unbind(ttm);
257 BUG_ON(ret);
258 ttm->state = tt_unbound;
259 }
260}
261
262int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem)
263{
264 int ret = 0;
265
266 if (!ttm)
267 return -EINVAL;
268
269 if (ttm->state == tt_bound)
270 return 0;
271
272 ret = ttm->bdev->driver->ttm_tt_populate(ttm);
273 if (ret)
274 return ret;
275
276 ret = ttm->func->bind(ttm, bo_mem);
277 if (unlikely(ret != 0))
278 return ret;
279
280 ttm->state = tt_bound;
281
282 return 0;
283}
284EXPORT_SYMBOL(ttm_tt_bind);
285
286int ttm_tt_swapin(struct ttm_tt *ttm)
287{
288 struct address_space *swap_space;
289 struct file *swap_storage;
290 struct page *from_page;
291 struct page *to_page;
292 int i;
293 int ret = -ENOMEM;
294
295 swap_storage = ttm->swap_storage;
296 BUG_ON(swap_storage == NULL);
297
298 swap_space = file_inode(swap_storage)->i_mapping;
299
300 for (i = 0; i < ttm->num_pages; ++i) {
301 from_page = shmem_read_mapping_page(swap_space, i);
302 if (IS_ERR(from_page)) {
303 ret = PTR_ERR(from_page);
304 goto out_err;
305 }
306 to_page = ttm->pages[i];
307 if (unlikely(to_page == NULL))
308 goto out_err;
309
310 copy_highpage(to_page, from_page);
311 page_cache_release(from_page);
312 }
313
314 if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP))
315 fput(swap_storage);
316 ttm->swap_storage = NULL;
317 ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
318
319 return 0;
320out_err:
321 return ret;
322}
323
324int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistent_swap_storage)
325{
326 struct address_space *swap_space;
327 struct file *swap_storage;
328 struct page *from_page;
329 struct page *to_page;
330 int i;
331 int ret = -ENOMEM;
332
333 BUG_ON(ttm->state != tt_unbound && ttm->state != tt_unpopulated);
334 BUG_ON(ttm->caching_state != tt_cached);
335
336 if (!persistent_swap_storage) {
337 swap_storage = shmem_file_setup("ttm swap",
338 ttm->num_pages << PAGE_SHIFT,
339 0);
340 if (unlikely(IS_ERR(swap_storage))) {
341 pr_err("Failed allocating swap storage\n");
342 return PTR_ERR(swap_storage);
343 }
344 } else
345 swap_storage = persistent_swap_storage;
346
347 swap_space = file_inode(swap_storage)->i_mapping;
348
349 for (i = 0; i < ttm->num_pages; ++i) {
350 from_page = ttm->pages[i];
351 if (unlikely(from_page == NULL))
352 continue;
353 to_page = shmem_read_mapping_page(swap_space, i);
354 if (unlikely(IS_ERR(to_page))) {
355 ret = PTR_ERR(to_page);
356 goto out_err;
357 }
358 copy_highpage(to_page, from_page);
359 set_page_dirty(to_page);
360 mark_page_accessed(to_page);
361 page_cache_release(to_page);
362 }
363
364 ttm_tt_unpopulate(ttm);
365 ttm->swap_storage = swap_storage;
366 ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
367 if (persistent_swap_storage)
368 ttm->page_flags |= TTM_PAGE_FLAG_PERSISTENT_SWAP;
369
370 return 0;
371out_err:
372 if (!persistent_swap_storage)
373 fput(swap_storage);
374
375 return ret;
376}
377
378static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
379{
380 pgoff_t i;
381 struct page **page = ttm->pages;
382
383 if (ttm->page_flags & TTM_PAGE_FLAG_SG)
384 return;
385
386 for (i = 0; i < ttm->num_pages; ++i) {
387 (*page)->mapping = NULL;
388 (*page++)->index = 0;
389 }
390}
391
392void ttm_tt_unpopulate(struct ttm_tt *ttm)
393{
394 if (ttm->state == tt_unpopulated)
395 return;
396
397 ttm_tt_clear_mapping(ttm);
398 ttm->bdev->driver->ttm_tt_unpopulate(ttm);
399}