]>
Commit | Line | Data |
---|---|---|
ba4e7d97 TH |
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 | ||
ba4e7d97 TH |
31 | #include <linux/vmalloc.h> |
32 | #include <linux/sched.h> | |
33 | #include <linux/highmem.h> | |
34 | #include <linux/pagemap.h> | |
35 | #include <linux/file.h> | |
36 | #include <linux/swap.h> | |
37 | #include "ttm/ttm_module.h" | |
38 | #include "ttm/ttm_bo_driver.h" | |
39 | #include "ttm/ttm_placement.h" | |
40 | ||
41 | static int ttm_tt_swapin(struct ttm_tt *ttm); | |
42 | ||
43 | #if defined(CONFIG_X86) | |
44 | static void ttm_tt_clflush_page(struct page *page) | |
45 | { | |
46 | uint8_t *page_virtual; | |
47 | unsigned int i; | |
48 | ||
49 | if (unlikely(page == NULL)) | |
50 | return; | |
51 | ||
52 | page_virtual = kmap_atomic(page, KM_USER0); | |
53 | ||
54 | for (i = 0; i < PAGE_SIZE; i += boot_cpu_data.x86_clflush_size) | |
55 | clflush(page_virtual + i); | |
56 | ||
57 | kunmap_atomic(page_virtual, KM_USER0); | |
58 | } | |
59 | ||
60 | static void ttm_tt_cache_flush_clflush(struct page *pages[], | |
61 | unsigned long num_pages) | |
62 | { | |
63 | unsigned long i; | |
64 | ||
65 | mb(); | |
66 | for (i = 0; i < num_pages; ++i) | |
67 | ttm_tt_clflush_page(*pages++); | |
68 | mb(); | |
69 | } | |
46f4b3ea | 70 | #elif !defined(__powerpc__) |
ba4e7d97 TH |
71 | static void ttm_tt_ipi_handler(void *null) |
72 | { | |
73 | ; | |
74 | } | |
75 | #endif | |
76 | ||
77 | void ttm_tt_cache_flush(struct page *pages[], unsigned long num_pages) | |
78 | { | |
79 | ||
80 | #if defined(CONFIG_X86) | |
81 | if (cpu_has_clflush) { | |
82 | ttm_tt_cache_flush_clflush(pages, num_pages); | |
83 | return; | |
84 | } | |
46f4b3ea MD |
85 | #elif defined(__powerpc__) |
86 | unsigned long i; | |
87 | ||
88 | for (i = 0; i < num_pages; ++i) { | |
89 | if (pages[i]) { | |
90 | unsigned long start = (unsigned long)page_address(pages[i]); | |
91 | flush_dcache_range(start, start + PAGE_SIZE); | |
92 | } | |
93 | } | |
ba4e7d97 TH |
94 | #else |
95 | if (on_each_cpu(ttm_tt_ipi_handler, NULL, 1) != 0) | |
96 | printk(KERN_ERR TTM_PFX | |
97 | "Timed out waiting for drm cache flush.\n"); | |
98 | #endif | |
99 | } | |
100 | ||
101 | /** | |
102 | * Allocates storage for pointers to the pages that back the ttm. | |
103 | * | |
104 | * Uses kmalloc if possible. Otherwise falls back to vmalloc. | |
105 | */ | |
106 | static void ttm_tt_alloc_page_directory(struct ttm_tt *ttm) | |
107 | { | |
108 | unsigned long size = ttm->num_pages * sizeof(*ttm->pages); | |
109 | ttm->pages = NULL; | |
110 | ||
111 | if (size <= PAGE_SIZE) | |
112 | ttm->pages = kzalloc(size, GFP_KERNEL); | |
113 | ||
114 | if (!ttm->pages) { | |
115 | ttm->pages = vmalloc_user(size); | |
116 | if (ttm->pages) | |
117 | ttm->page_flags |= TTM_PAGE_FLAG_VMALLOC; | |
118 | } | |
119 | } | |
120 | ||
121 | static void ttm_tt_free_page_directory(struct ttm_tt *ttm) | |
122 | { | |
123 | if (ttm->page_flags & TTM_PAGE_FLAG_VMALLOC) { | |
124 | vfree(ttm->pages); | |
125 | ttm->page_flags &= ~TTM_PAGE_FLAG_VMALLOC; | |
126 | } else { | |
127 | kfree(ttm->pages); | |
128 | } | |
129 | ttm->pages = NULL; | |
130 | } | |
131 | ||
132 | static struct page *ttm_tt_alloc_page(unsigned page_flags) | |
133 | { | |
134 | if (page_flags & TTM_PAGE_FLAG_ZERO_ALLOC) | |
135 | return alloc_page(GFP_HIGHUSER | __GFP_ZERO); | |
136 | ||
137 | return alloc_page(GFP_HIGHUSER); | |
138 | } | |
139 | ||
140 | static void ttm_tt_free_user_pages(struct ttm_tt *ttm) | |
141 | { | |
142 | int write; | |
143 | int dirty; | |
144 | struct page *page; | |
145 | int i; | |
146 | struct ttm_backend *be = ttm->be; | |
147 | ||
148 | BUG_ON(!(ttm->page_flags & TTM_PAGE_FLAG_USER)); | |
149 | write = ((ttm->page_flags & TTM_PAGE_FLAG_WRITE) != 0); | |
150 | dirty = ((ttm->page_flags & TTM_PAGE_FLAG_USER_DIRTY) != 0); | |
151 | ||
152 | if (be) | |
153 | be->func->clear(be); | |
154 | ||
155 | for (i = 0; i < ttm->num_pages; ++i) { | |
156 | page = ttm->pages[i]; | |
157 | if (page == NULL) | |
158 | continue; | |
159 | ||
160 | if (page == ttm->dummy_read_page) { | |
161 | BUG_ON(write); | |
162 | continue; | |
163 | } | |
164 | ||
165 | if (write && dirty && !PageReserved(page)) | |
166 | set_page_dirty_lock(page); | |
167 | ||
168 | ttm->pages[i] = NULL; | |
169 | ttm_mem_global_free(ttm->bdev->mem_glob, PAGE_SIZE, false); | |
170 | put_page(page); | |
171 | } | |
172 | ttm->state = tt_unpopulated; | |
173 | ttm->first_himem_page = ttm->num_pages; | |
174 | ttm->last_lomem_page = -1; | |
175 | } | |
176 | ||
177 | static struct page *__ttm_tt_get_page(struct ttm_tt *ttm, int index) | |
178 | { | |
179 | struct page *p; | |
180 | struct ttm_bo_device *bdev = ttm->bdev; | |
181 | struct ttm_mem_global *mem_glob = bdev->mem_glob; | |
182 | int ret; | |
183 | ||
184 | while (NULL == (p = ttm->pages[index])) { | |
185 | p = ttm_tt_alloc_page(ttm->page_flags); | |
186 | ||
187 | if (!p) | |
188 | return NULL; | |
189 | ||
190 | if (PageHighMem(p)) { | |
191 | ret = | |
192 | ttm_mem_global_alloc(mem_glob, PAGE_SIZE, | |
193 | false, false, true); | |
194 | if (unlikely(ret != 0)) | |
195 | goto out_err; | |
196 | ttm->pages[--ttm->first_himem_page] = p; | |
197 | } else { | |
198 | ret = | |
199 | ttm_mem_global_alloc(mem_glob, PAGE_SIZE, | |
200 | false, false, false); | |
201 | if (unlikely(ret != 0)) | |
202 | goto out_err; | |
203 | ttm->pages[++ttm->last_lomem_page] = p; | |
204 | } | |
205 | } | |
206 | return p; | |
207 | out_err: | |
208 | put_page(p); | |
209 | return NULL; | |
210 | } | |
211 | ||
212 | struct page *ttm_tt_get_page(struct ttm_tt *ttm, int index) | |
213 | { | |
214 | int ret; | |
215 | ||
216 | if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) { | |
217 | ret = ttm_tt_swapin(ttm); | |
218 | if (unlikely(ret != 0)) | |
219 | return NULL; | |
220 | } | |
221 | return __ttm_tt_get_page(ttm, index); | |
222 | } | |
223 | ||
224 | int ttm_tt_populate(struct ttm_tt *ttm) | |
225 | { | |
226 | struct page *page; | |
227 | unsigned long i; | |
228 | struct ttm_backend *be; | |
229 | int ret; | |
230 | ||
231 | if (ttm->state != tt_unpopulated) | |
232 | return 0; | |
233 | ||
234 | if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) { | |
235 | ret = ttm_tt_swapin(ttm); | |
236 | if (unlikely(ret != 0)) | |
237 | return ret; | |
238 | } | |
239 | ||
240 | be = ttm->be; | |
241 | ||
242 | for (i = 0; i < ttm->num_pages; ++i) { | |
243 | page = __ttm_tt_get_page(ttm, i); | |
244 | if (!page) | |
245 | return -ENOMEM; | |
246 | } | |
247 | ||
248 | be->func->populate(be, ttm->num_pages, ttm->pages, | |
249 | ttm->dummy_read_page); | |
250 | ttm->state = tt_unbound; | |
251 | return 0; | |
252 | } | |
253 | ||
254 | #ifdef CONFIG_X86 | |
255 | static inline int ttm_tt_set_page_caching(struct page *p, | |
256 | enum ttm_caching_state c_state) | |
257 | { | |
258 | if (PageHighMem(p)) | |
259 | return 0; | |
260 | ||
261 | switch (c_state) { | |
262 | case tt_cached: | |
263 | return set_pages_wb(p, 1); | |
264 | case tt_wc: | |
265 | return set_memory_wc((unsigned long) page_address(p), 1); | |
266 | default: | |
267 | return set_pages_uc(p, 1); | |
268 | } | |
269 | } | |
270 | #else /* CONFIG_X86 */ | |
271 | static inline int ttm_tt_set_page_caching(struct page *p, | |
272 | enum ttm_caching_state c_state) | |
273 | { | |
274 | return 0; | |
275 | } | |
276 | #endif /* CONFIG_X86 */ | |
277 | ||
278 | /* | |
279 | * Change caching policy for the linear kernel map | |
280 | * for range of pages in a ttm. | |
281 | */ | |
282 | ||
283 | static int ttm_tt_set_caching(struct ttm_tt *ttm, | |
284 | enum ttm_caching_state c_state) | |
285 | { | |
286 | int i, j; | |
287 | struct page *cur_page; | |
288 | int ret; | |
289 | ||
290 | if (ttm->caching_state == c_state) | |
291 | return 0; | |
292 | ||
293 | if (c_state != tt_cached) { | |
294 | ret = ttm_tt_populate(ttm); | |
295 | if (unlikely(ret != 0)) | |
296 | return ret; | |
297 | } | |
298 | ||
299 | if (ttm->caching_state == tt_cached) | |
300 | ttm_tt_cache_flush(ttm->pages, ttm->num_pages); | |
301 | ||
302 | for (i = 0; i < ttm->num_pages; ++i) { | |
303 | cur_page = ttm->pages[i]; | |
304 | if (likely(cur_page != NULL)) { | |
305 | ret = ttm_tt_set_page_caching(cur_page, c_state); | |
306 | if (unlikely(ret != 0)) | |
307 | goto out_err; | |
308 | } | |
309 | } | |
310 | ||
311 | ttm->caching_state = c_state; | |
312 | ||
313 | return 0; | |
314 | ||
315 | out_err: | |
316 | for (j = 0; j < i; ++j) { | |
317 | cur_page = ttm->pages[j]; | |
318 | if (likely(cur_page != NULL)) { | |
319 | (void)ttm_tt_set_page_caching(cur_page, | |
320 | ttm->caching_state); | |
321 | } | |
322 | } | |
323 | ||
324 | return ret; | |
325 | } | |
326 | ||
327 | int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement) | |
328 | { | |
329 | enum ttm_caching_state state; | |
330 | ||
331 | if (placement & TTM_PL_FLAG_WC) | |
332 | state = tt_wc; | |
333 | else if (placement & TTM_PL_FLAG_UNCACHED) | |
334 | state = tt_uncached; | |
335 | else | |
336 | state = tt_cached; | |
337 | ||
338 | return ttm_tt_set_caching(ttm, state); | |
339 | } | |
340 | ||
341 | static void ttm_tt_free_alloced_pages(struct ttm_tt *ttm) | |
342 | { | |
343 | int i; | |
344 | struct page *cur_page; | |
345 | struct ttm_backend *be = ttm->be; | |
346 | ||
347 | if (be) | |
348 | be->func->clear(be); | |
349 | (void)ttm_tt_set_caching(ttm, tt_cached); | |
350 | for (i = 0; i < ttm->num_pages; ++i) { | |
351 | cur_page = ttm->pages[i]; | |
352 | ttm->pages[i] = NULL; | |
353 | if (cur_page) { | |
354 | if (page_count(cur_page) != 1) | |
355 | printk(KERN_ERR TTM_PFX | |
356 | "Erroneous page count. " | |
357 | "Leaking pages.\n"); | |
358 | ttm_mem_global_free(ttm->bdev->mem_glob, PAGE_SIZE, | |
359 | PageHighMem(cur_page)); | |
360 | __free_page(cur_page); | |
361 | } | |
362 | } | |
363 | ttm->state = tt_unpopulated; | |
364 | ttm->first_himem_page = ttm->num_pages; | |
365 | ttm->last_lomem_page = -1; | |
366 | } | |
367 | ||
368 | void ttm_tt_destroy(struct ttm_tt *ttm) | |
369 | { | |
370 | struct ttm_backend *be; | |
371 | ||
372 | if (unlikely(ttm == NULL)) | |
373 | return; | |
374 | ||
375 | be = ttm->be; | |
376 | if (likely(be != NULL)) { | |
377 | be->func->destroy(be); | |
378 | ttm->be = NULL; | |
379 | } | |
380 | ||
381 | if (likely(ttm->pages != NULL)) { | |
382 | if (ttm->page_flags & TTM_PAGE_FLAG_USER) | |
383 | ttm_tt_free_user_pages(ttm); | |
384 | else | |
385 | ttm_tt_free_alloced_pages(ttm); | |
386 | ||
387 | ttm_tt_free_page_directory(ttm); | |
388 | } | |
389 | ||
390 | if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTANT_SWAP) && | |
391 | ttm->swap_storage) | |
392 | fput(ttm->swap_storage); | |
393 | ||
394 | kfree(ttm); | |
395 | } | |
396 | ||
397 | int ttm_tt_set_user(struct ttm_tt *ttm, | |
398 | struct task_struct *tsk, | |
399 | unsigned long start, unsigned long num_pages) | |
400 | { | |
401 | struct mm_struct *mm = tsk->mm; | |
402 | int ret; | |
403 | int write = (ttm->page_flags & TTM_PAGE_FLAG_WRITE) != 0; | |
404 | struct ttm_mem_global *mem_glob = ttm->bdev->mem_glob; | |
405 | ||
406 | BUG_ON(num_pages != ttm->num_pages); | |
407 | BUG_ON((ttm->page_flags & TTM_PAGE_FLAG_USER) == 0); | |
408 | ||
409 | /** | |
410 | * Account user pages as lowmem pages for now. | |
411 | */ | |
412 | ||
413 | ret = ttm_mem_global_alloc(mem_glob, num_pages * PAGE_SIZE, | |
414 | false, false, false); | |
415 | if (unlikely(ret != 0)) | |
416 | return ret; | |
417 | ||
418 | down_read(&mm->mmap_sem); | |
419 | ret = get_user_pages(tsk, mm, start, num_pages, | |
420 | write, 0, ttm->pages, NULL); | |
421 | up_read(&mm->mmap_sem); | |
422 | ||
423 | if (ret != num_pages && write) { | |
424 | ttm_tt_free_user_pages(ttm); | |
425 | ttm_mem_global_free(mem_glob, num_pages * PAGE_SIZE, false); | |
426 | return -ENOMEM; | |
427 | } | |
428 | ||
429 | ttm->tsk = tsk; | |
430 | ttm->start = start; | |
431 | ttm->state = tt_unbound; | |
432 | ||
433 | return 0; | |
434 | } | |
435 | ||
436 | struct ttm_tt *ttm_tt_create(struct ttm_bo_device *bdev, unsigned long size, | |
437 | uint32_t page_flags, struct page *dummy_read_page) | |
438 | { | |
439 | struct ttm_bo_driver *bo_driver = bdev->driver; | |
440 | struct ttm_tt *ttm; | |
441 | ||
442 | if (!bo_driver) | |
443 | return NULL; | |
444 | ||
445 | ttm = kzalloc(sizeof(*ttm), GFP_KERNEL); | |
446 | if (!ttm) | |
447 | return NULL; | |
448 | ||
449 | ttm->bdev = bdev; | |
450 | ||
451 | ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
452 | ttm->first_himem_page = ttm->num_pages; | |
453 | ttm->last_lomem_page = -1; | |
454 | ttm->caching_state = tt_cached; | |
455 | ttm->page_flags = page_flags; | |
456 | ||
457 | ttm->dummy_read_page = dummy_read_page; | |
458 | ||
459 | ttm_tt_alloc_page_directory(ttm); | |
460 | if (!ttm->pages) { | |
461 | ttm_tt_destroy(ttm); | |
462 | printk(KERN_ERR TTM_PFX "Failed allocating page table\n"); | |
463 | return NULL; | |
464 | } | |
465 | ttm->be = bo_driver->create_ttm_backend_entry(bdev); | |
466 | if (!ttm->be) { | |
467 | ttm_tt_destroy(ttm); | |
468 | printk(KERN_ERR TTM_PFX "Failed creating ttm backend entry\n"); | |
469 | return NULL; | |
470 | } | |
471 | ttm->state = tt_unpopulated; | |
472 | return ttm; | |
473 | } | |
474 | ||
475 | void ttm_tt_unbind(struct ttm_tt *ttm) | |
476 | { | |
477 | int ret; | |
478 | struct ttm_backend *be = ttm->be; | |
479 | ||
480 | if (ttm->state == tt_bound) { | |
481 | ret = be->func->unbind(be); | |
482 | BUG_ON(ret); | |
483 | ttm->state = tt_unbound; | |
484 | } | |
485 | } | |
486 | ||
487 | int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem) | |
488 | { | |
489 | int ret = 0; | |
490 | struct ttm_backend *be; | |
491 | ||
492 | if (!ttm) | |
493 | return -EINVAL; | |
494 | ||
495 | if (ttm->state == tt_bound) | |
496 | return 0; | |
497 | ||
498 | be = ttm->be; | |
499 | ||
500 | ret = ttm_tt_populate(ttm); | |
501 | if (ret) | |
502 | return ret; | |
503 | ||
504 | ret = be->func->bind(be, bo_mem); | |
505 | if (ret) { | |
506 | printk(KERN_ERR TTM_PFX "Couldn't bind backend.\n"); | |
507 | return ret; | |
508 | } | |
509 | ||
510 | ttm->state = tt_bound; | |
511 | ||
512 | if (ttm->page_flags & TTM_PAGE_FLAG_USER) | |
513 | ttm->page_flags |= TTM_PAGE_FLAG_USER_DIRTY; | |
514 | return 0; | |
515 | } | |
516 | EXPORT_SYMBOL(ttm_tt_bind); | |
517 | ||
518 | static int ttm_tt_swapin(struct ttm_tt *ttm) | |
519 | { | |
520 | struct address_space *swap_space; | |
521 | struct file *swap_storage; | |
522 | struct page *from_page; | |
523 | struct page *to_page; | |
524 | void *from_virtual; | |
525 | void *to_virtual; | |
526 | int i; | |
527 | int ret; | |
528 | ||
529 | if (ttm->page_flags & TTM_PAGE_FLAG_USER) { | |
530 | ret = ttm_tt_set_user(ttm, ttm->tsk, ttm->start, | |
531 | ttm->num_pages); | |
532 | if (unlikely(ret != 0)) | |
533 | return ret; | |
534 | ||
535 | ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED; | |
536 | return 0; | |
537 | } | |
538 | ||
539 | swap_storage = ttm->swap_storage; | |
540 | BUG_ON(swap_storage == NULL); | |
541 | ||
542 | swap_space = swap_storage->f_path.dentry->d_inode->i_mapping; | |
543 | ||
544 | for (i = 0; i < ttm->num_pages; ++i) { | |
545 | from_page = read_mapping_page(swap_space, i, NULL); | |
546 | if (IS_ERR(from_page)) | |
547 | goto out_err; | |
548 | to_page = __ttm_tt_get_page(ttm, i); | |
549 | if (unlikely(to_page == NULL)) | |
550 | goto out_err; | |
551 | ||
552 | preempt_disable(); | |
553 | from_virtual = kmap_atomic(from_page, KM_USER0); | |
554 | to_virtual = kmap_atomic(to_page, KM_USER1); | |
555 | memcpy(to_virtual, from_virtual, PAGE_SIZE); | |
556 | kunmap_atomic(to_virtual, KM_USER1); | |
557 | kunmap_atomic(from_virtual, KM_USER0); | |
558 | preempt_enable(); | |
559 | page_cache_release(from_page); | |
560 | } | |
561 | ||
562 | if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTANT_SWAP)) | |
563 | fput(swap_storage); | |
564 | ttm->swap_storage = NULL; | |
565 | ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED; | |
566 | ||
567 | return 0; | |
568 | out_err: | |
569 | ttm_tt_free_alloced_pages(ttm); | |
570 | return -ENOMEM; | |
571 | } | |
572 | ||
573 | int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistant_swap_storage) | |
574 | { | |
575 | struct address_space *swap_space; | |
576 | struct file *swap_storage; | |
577 | struct page *from_page; | |
578 | struct page *to_page; | |
579 | void *from_virtual; | |
580 | void *to_virtual; | |
581 | int i; | |
582 | ||
583 | BUG_ON(ttm->state != tt_unbound && ttm->state != tt_unpopulated); | |
584 | BUG_ON(ttm->caching_state != tt_cached); | |
585 | ||
586 | /* | |
587 | * For user buffers, just unpin the pages, as there should be | |
588 | * vma references. | |
589 | */ | |
590 | ||
591 | if (ttm->page_flags & TTM_PAGE_FLAG_USER) { | |
592 | ttm_tt_free_user_pages(ttm); | |
593 | ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED; | |
594 | ttm->swap_storage = NULL; | |
595 | return 0; | |
596 | } | |
597 | ||
598 | if (!persistant_swap_storage) { | |
599 | swap_storage = shmem_file_setup("ttm swap", | |
600 | ttm->num_pages << PAGE_SHIFT, | |
601 | 0); | |
602 | if (unlikely(IS_ERR(swap_storage))) { | |
603 | printk(KERN_ERR "Failed allocating swap storage.\n"); | |
604 | return -ENOMEM; | |
605 | } | |
606 | } else | |
607 | swap_storage = persistant_swap_storage; | |
608 | ||
609 | swap_space = swap_storage->f_path.dentry->d_inode->i_mapping; | |
610 | ||
611 | for (i = 0; i < ttm->num_pages; ++i) { | |
612 | from_page = ttm->pages[i]; | |
613 | if (unlikely(from_page == NULL)) | |
614 | continue; | |
615 | to_page = read_mapping_page(swap_space, i, NULL); | |
616 | if (unlikely(to_page == NULL)) | |
617 | goto out_err; | |
618 | ||
619 | preempt_disable(); | |
620 | from_virtual = kmap_atomic(from_page, KM_USER0); | |
621 | to_virtual = kmap_atomic(to_page, KM_USER1); | |
622 | memcpy(to_virtual, from_virtual, PAGE_SIZE); | |
623 | kunmap_atomic(to_virtual, KM_USER1); | |
624 | kunmap_atomic(from_virtual, KM_USER0); | |
625 | preempt_enable(); | |
626 | set_page_dirty(to_page); | |
627 | mark_page_accessed(to_page); | |
628 | page_cache_release(to_page); | |
629 | } | |
630 | ||
631 | ttm_tt_free_alloced_pages(ttm); | |
632 | ttm->swap_storage = swap_storage; | |
633 | ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED; | |
634 | if (persistant_swap_storage) | |
635 | ttm->page_flags |= TTM_PAGE_FLAG_PERSISTANT_SWAP; | |
636 | ||
637 | return 0; | |
638 | out_err: | |
639 | if (!persistant_swap_storage) | |
640 | fput(swap_storage); | |
641 | ||
642 | return -ENOMEM; | |
643 | } |