ttm: Introduce a placeholder for DMA (bus) addresses.
[linux-2.6.git] / drivers / gpu / drm / ttm / ttm_tt.c
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
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12  * the following conditions:
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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
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26  **************************************************************************/
27 /*
28  * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29  */
30
31 #include <linux/sched.h>
32 #include <linux/highmem.h>
33 #include <linux/pagemap.h>
34 #include <linux/file.h>
35 #include <linux/swap.h>
36 #include <linux/slab.h>
37 #include "drm_cache.h"
38 #include "drm_mem_util.h"
39 #include "ttm/ttm_module.h"
40 #include "ttm/ttm_bo_driver.h"
41 #include "ttm/ttm_placement.h"
42 #include "ttm/ttm_page_alloc.h"
43
44 static int ttm_tt_swapin(struct ttm_tt *ttm);
45
46 /**
47  * Allocates storage for pointers to the pages that back the ttm.
48  */
49 static void ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
50 {
51         ttm->pages = drm_calloc_large(ttm->num_pages, sizeof(*ttm->pages));
52         ttm->dma_address = drm_calloc_large(ttm->num_pages,
53                                             sizeof(*ttm->dma_address));
54 }
55
56 static void ttm_tt_free_page_directory(struct ttm_tt *ttm)
57 {
58         drm_free_large(ttm->pages);
59         ttm->pages = NULL;
60         drm_free_large(ttm->dma_address);
61         ttm->dma_address = NULL;
62 }
63
64 static void ttm_tt_free_user_pages(struct ttm_tt *ttm)
65 {
66         int write;
67         int dirty;
68         struct page *page;
69         int i;
70         struct ttm_backend *be = ttm->be;
71
72         BUG_ON(!(ttm->page_flags & TTM_PAGE_FLAG_USER));
73         write = ((ttm->page_flags & TTM_PAGE_FLAG_WRITE) != 0);
74         dirty = ((ttm->page_flags & TTM_PAGE_FLAG_USER_DIRTY) != 0);
75
76         if (be)
77                 be->func->clear(be);
78
79         for (i = 0; i < ttm->num_pages; ++i) {
80                 page = ttm->pages[i];
81                 if (page == NULL)
82                         continue;
83
84                 if (page == ttm->dummy_read_page) {
85                         BUG_ON(write);
86                         continue;
87                 }
88
89                 if (write && dirty && !PageReserved(page))
90                         set_page_dirty_lock(page);
91
92                 ttm->pages[i] = NULL;
93                 ttm_mem_global_free(ttm->glob->mem_glob, PAGE_SIZE);
94                 put_page(page);
95         }
96         ttm->state = tt_unpopulated;
97         ttm->first_himem_page = ttm->num_pages;
98         ttm->last_lomem_page = -1;
99 }
100
101 static struct page *__ttm_tt_get_page(struct ttm_tt *ttm, int index)
102 {
103         struct page *p;
104         struct list_head h;
105         struct ttm_mem_global *mem_glob = ttm->glob->mem_glob;
106         int ret;
107
108         while (NULL == (p = ttm->pages[index])) {
109
110                 INIT_LIST_HEAD(&h);
111
112                 ret = ttm_get_pages(&h, ttm->page_flags, ttm->caching_state, 1,
113                                     &ttm->dma_address[index]);
114
115                 if (ret != 0)
116                         return NULL;
117
118                 p = list_first_entry(&h, struct page, lru);
119
120                 ret = ttm_mem_global_alloc_page(mem_glob, p, false, false);
121                 if (unlikely(ret != 0))
122                         goto out_err;
123
124                 if (PageHighMem(p))
125                         ttm->pages[--ttm->first_himem_page] = p;
126                 else
127                         ttm->pages[++ttm->last_lomem_page] = p;
128         }
129         return p;
130 out_err:
131         put_page(p);
132         return NULL;
133 }
134
135 struct page *ttm_tt_get_page(struct ttm_tt *ttm, int index)
136 {
137         int ret;
138
139         if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
140                 ret = ttm_tt_swapin(ttm);
141                 if (unlikely(ret != 0))
142                         return NULL;
143         }
144         return __ttm_tt_get_page(ttm, index);
145 }
146
147 int ttm_tt_populate(struct ttm_tt *ttm)
148 {
149         struct page *page;
150         unsigned long i;
151         struct ttm_backend *be;
152         int ret;
153
154         if (ttm->state != tt_unpopulated)
155                 return 0;
156
157         if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
158                 ret = ttm_tt_swapin(ttm);
159                 if (unlikely(ret != 0))
160                         return ret;
161         }
162
163         be = ttm->be;
164
165         for (i = 0; i < ttm->num_pages; ++i) {
166                 page = __ttm_tt_get_page(ttm, i);
167                 if (!page)
168                         return -ENOMEM;
169         }
170
171         be->func->populate(be, ttm->num_pages, ttm->pages,
172                            ttm->dummy_read_page);
173         ttm->state = tt_unbound;
174         return 0;
175 }
176 EXPORT_SYMBOL(ttm_tt_populate);
177
178 #ifdef CONFIG_X86
179 static inline int ttm_tt_set_page_caching(struct page *p,
180                                           enum ttm_caching_state c_old,
181                                           enum ttm_caching_state c_new)
182 {
183         int ret = 0;
184
185         if (PageHighMem(p))
186                 return 0;
187
188         if (c_old != tt_cached) {
189                 /* p isn't in the default caching state, set it to
190                  * writeback first to free its current memtype. */
191
192                 ret = set_pages_wb(p, 1);
193                 if (ret)
194                         return ret;
195         }
196
197         if (c_new == tt_wc)
198                 ret = set_memory_wc((unsigned long) page_address(p), 1);
199         else if (c_new == tt_uncached)
200                 ret = set_pages_uc(p, 1);
201
202         return ret;
203 }
204 #else /* CONFIG_X86 */
205 static inline int ttm_tt_set_page_caching(struct page *p,
206                                           enum ttm_caching_state c_old,
207                                           enum ttm_caching_state c_new)
208 {
209         return 0;
210 }
211 #endif /* CONFIG_X86 */
212
213 /*
214  * Change caching policy for the linear kernel map
215  * for range of pages in a ttm.
216  */
217
218 static int ttm_tt_set_caching(struct ttm_tt *ttm,
219                               enum ttm_caching_state c_state)
220 {
221         int i, j;
222         struct page *cur_page;
223         int ret;
224
225         if (ttm->caching_state == c_state)
226                 return 0;
227
228         if (ttm->state == tt_unpopulated) {
229                 /* Change caching but don't populate */
230                 ttm->caching_state = c_state;
231                 return 0;
232         }
233
234         if (ttm->caching_state == tt_cached)
235                 drm_clflush_pages(ttm->pages, ttm->num_pages);
236
237         for (i = 0; i < ttm->num_pages; ++i) {
238                 cur_page = ttm->pages[i];
239                 if (likely(cur_page != NULL)) {
240                         ret = ttm_tt_set_page_caching(cur_page,
241                                                       ttm->caching_state,
242                                                       c_state);
243                         if (unlikely(ret != 0))
244                                 goto out_err;
245                 }
246         }
247
248         ttm->caching_state = c_state;
249
250         return 0;
251
252 out_err:
253         for (j = 0; j < i; ++j) {
254                 cur_page = ttm->pages[j];
255                 if (likely(cur_page != NULL)) {
256                         (void)ttm_tt_set_page_caching(cur_page, c_state,
257                                                       ttm->caching_state);
258                 }
259         }
260
261         return ret;
262 }
263
264 int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement)
265 {
266         enum ttm_caching_state state;
267
268         if (placement & TTM_PL_FLAG_WC)
269                 state = tt_wc;
270         else if (placement & TTM_PL_FLAG_UNCACHED)
271                 state = tt_uncached;
272         else
273                 state = tt_cached;
274
275         return ttm_tt_set_caching(ttm, state);
276 }
277 EXPORT_SYMBOL(ttm_tt_set_placement_caching);
278
279 static void ttm_tt_free_alloced_pages(struct ttm_tt *ttm)
280 {
281         int i;
282         unsigned count = 0;
283         struct list_head h;
284         struct page *cur_page;
285         struct ttm_backend *be = ttm->be;
286
287         INIT_LIST_HEAD(&h);
288
289         if (be)
290                 be->func->clear(be);
291         for (i = 0; i < ttm->num_pages; ++i) {
292
293                 cur_page = ttm->pages[i];
294                 ttm->pages[i] = NULL;
295                 if (cur_page) {
296                         if (page_count(cur_page) != 1)
297                                 printk(KERN_ERR TTM_PFX
298                                        "Erroneous page count. "
299                                        "Leaking pages.\n");
300                         ttm_mem_global_free_page(ttm->glob->mem_glob,
301                                                  cur_page);
302                         list_add(&cur_page->lru, &h);
303                         count++;
304                 }
305         }
306         ttm_put_pages(&h, count, ttm->page_flags, ttm->caching_state,
307                       ttm->dma_address);
308         ttm->state = tt_unpopulated;
309         ttm->first_himem_page = ttm->num_pages;
310         ttm->last_lomem_page = -1;
311 }
312
313 void ttm_tt_destroy(struct ttm_tt *ttm)
314 {
315         struct ttm_backend *be;
316
317         if (unlikely(ttm == NULL))
318                 return;
319
320         be = ttm->be;
321         if (likely(be != NULL)) {
322                 be->func->destroy(be);
323                 ttm->be = NULL;
324         }
325
326         if (likely(ttm->pages != NULL)) {
327                 if (ttm->page_flags & TTM_PAGE_FLAG_USER)
328                         ttm_tt_free_user_pages(ttm);
329                 else
330                         ttm_tt_free_alloced_pages(ttm);
331
332                 ttm_tt_free_page_directory(ttm);
333         }
334
335         if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTANT_SWAP) &&
336             ttm->swap_storage)
337                 fput(ttm->swap_storage);
338
339         kfree(ttm);
340 }
341
342 int ttm_tt_set_user(struct ttm_tt *ttm,
343                     struct task_struct *tsk,
344                     unsigned long start, unsigned long num_pages)
345 {
346         struct mm_struct *mm = tsk->mm;
347         int ret;
348         int write = (ttm->page_flags & TTM_PAGE_FLAG_WRITE) != 0;
349         struct ttm_mem_global *mem_glob = ttm->glob->mem_glob;
350
351         BUG_ON(num_pages != ttm->num_pages);
352         BUG_ON((ttm->page_flags & TTM_PAGE_FLAG_USER) == 0);
353
354         /**
355          * Account user pages as lowmem pages for now.
356          */
357
358         ret = ttm_mem_global_alloc(mem_glob, num_pages * PAGE_SIZE,
359                                    false, false);
360         if (unlikely(ret != 0))
361                 return ret;
362
363         down_read(&mm->mmap_sem);
364         ret = get_user_pages(tsk, mm, start, num_pages,
365                              write, 0, ttm->pages, NULL);
366         up_read(&mm->mmap_sem);
367
368         if (ret != num_pages && write) {
369                 ttm_tt_free_user_pages(ttm);
370                 ttm_mem_global_free(mem_glob, num_pages * PAGE_SIZE);
371                 return -ENOMEM;
372         }
373
374         ttm->tsk = tsk;
375         ttm->start = start;
376         ttm->state = tt_unbound;
377
378         return 0;
379 }
380
381 struct ttm_tt *ttm_tt_create(struct ttm_bo_device *bdev, unsigned long size,
382                              uint32_t page_flags, struct page *dummy_read_page)
383 {
384         struct ttm_bo_driver *bo_driver = bdev->driver;
385         struct ttm_tt *ttm;
386
387         if (!bo_driver)
388                 return NULL;
389
390         ttm = kzalloc(sizeof(*ttm), GFP_KERNEL);
391         if (!ttm)
392                 return NULL;
393
394         ttm->glob = bdev->glob;
395         ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
396         ttm->first_himem_page = ttm->num_pages;
397         ttm->last_lomem_page = -1;
398         ttm->caching_state = tt_cached;
399         ttm->page_flags = page_flags;
400
401         ttm->dummy_read_page = dummy_read_page;
402
403         ttm_tt_alloc_page_directory(ttm);
404         if (!ttm->pages) {
405                 ttm_tt_destroy(ttm);
406                 printk(KERN_ERR TTM_PFX "Failed allocating page table\n");
407                 return NULL;
408         }
409         ttm->be = bo_driver->create_ttm_backend_entry(bdev);
410         if (!ttm->be) {
411                 ttm_tt_destroy(ttm);
412                 printk(KERN_ERR TTM_PFX "Failed creating ttm backend entry\n");
413                 return NULL;
414         }
415         ttm->state = tt_unpopulated;
416         return ttm;
417 }
418
419 void ttm_tt_unbind(struct ttm_tt *ttm)
420 {
421         int ret;
422         struct ttm_backend *be = ttm->be;
423
424         if (ttm->state == tt_bound) {
425                 ret = be->func->unbind(be);
426                 BUG_ON(ret);
427                 ttm->state = tt_unbound;
428         }
429 }
430
431 int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem)
432 {
433         int ret = 0;
434         struct ttm_backend *be;
435
436         if (!ttm)
437                 return -EINVAL;
438
439         if (ttm->state == tt_bound)
440                 return 0;
441
442         be = ttm->be;
443
444         ret = ttm_tt_populate(ttm);
445         if (ret)
446                 return ret;
447
448         ret = be->func->bind(be, bo_mem);
449         if (unlikely(ret != 0))
450                 return ret;
451
452         ttm->state = tt_bound;
453
454         if (ttm->page_flags & TTM_PAGE_FLAG_USER)
455                 ttm->page_flags |= TTM_PAGE_FLAG_USER_DIRTY;
456         return 0;
457 }
458 EXPORT_SYMBOL(ttm_tt_bind);
459
460 static int ttm_tt_swapin(struct ttm_tt *ttm)
461 {
462         struct address_space *swap_space;
463         struct file *swap_storage;
464         struct page *from_page;
465         struct page *to_page;
466         void *from_virtual;
467         void *to_virtual;
468         int i;
469         int ret = -ENOMEM;
470
471         if (ttm->page_flags & TTM_PAGE_FLAG_USER) {
472                 ret = ttm_tt_set_user(ttm, ttm->tsk, ttm->start,
473                                       ttm->num_pages);
474                 if (unlikely(ret != 0))
475                         return ret;
476
477                 ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
478                 return 0;
479         }
480
481         swap_storage = ttm->swap_storage;
482         BUG_ON(swap_storage == NULL);
483
484         swap_space = swap_storage->f_path.dentry->d_inode->i_mapping;
485
486         for (i = 0; i < ttm->num_pages; ++i) {
487                 from_page = read_mapping_page(swap_space, i, NULL);
488                 if (IS_ERR(from_page)) {
489                         ret = PTR_ERR(from_page);
490                         goto out_err;
491                 }
492                 to_page = __ttm_tt_get_page(ttm, i);
493                 if (unlikely(to_page == NULL))
494                         goto out_err;
495
496                 preempt_disable();
497                 from_virtual = kmap_atomic(from_page, KM_USER0);
498                 to_virtual = kmap_atomic(to_page, KM_USER1);
499                 memcpy(to_virtual, from_virtual, PAGE_SIZE);
500                 kunmap_atomic(to_virtual, KM_USER1);
501                 kunmap_atomic(from_virtual, KM_USER0);
502                 preempt_enable();
503                 page_cache_release(from_page);
504         }
505
506         if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTANT_SWAP))
507                 fput(swap_storage);
508         ttm->swap_storage = NULL;
509         ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
510
511         return 0;
512 out_err:
513         ttm_tt_free_alloced_pages(ttm);
514         return ret;
515 }
516
517 int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistant_swap_storage)
518 {
519         struct address_space *swap_space;
520         struct file *swap_storage;
521         struct page *from_page;
522         struct page *to_page;
523         void *from_virtual;
524         void *to_virtual;
525         int i;
526         int ret = -ENOMEM;
527
528         BUG_ON(ttm->state != tt_unbound && ttm->state != tt_unpopulated);
529         BUG_ON(ttm->caching_state != tt_cached);
530
531         /*
532          * For user buffers, just unpin the pages, as there should be
533          * vma references.
534          */
535
536         if (ttm->page_flags & TTM_PAGE_FLAG_USER) {
537                 ttm_tt_free_user_pages(ttm);
538                 ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
539                 ttm->swap_storage = NULL;
540                 return 0;
541         }
542
543         if (!persistant_swap_storage) {
544                 swap_storage = shmem_file_setup("ttm swap",
545                                                 ttm->num_pages << PAGE_SHIFT,
546                                                 0);
547                 if (unlikely(IS_ERR(swap_storage))) {
548                         printk(KERN_ERR "Failed allocating swap storage.\n");
549                         return PTR_ERR(swap_storage);
550                 }
551         } else
552                 swap_storage = persistant_swap_storage;
553
554         swap_space = swap_storage->f_path.dentry->d_inode->i_mapping;
555
556         for (i = 0; i < ttm->num_pages; ++i) {
557                 from_page = ttm->pages[i];
558                 if (unlikely(from_page == NULL))
559                         continue;
560                 to_page = read_mapping_page(swap_space, i, NULL);
561                 if (unlikely(IS_ERR(to_page))) {
562                         ret = PTR_ERR(to_page);
563                         goto out_err;
564                 }
565                 preempt_disable();
566                 from_virtual = kmap_atomic(from_page, KM_USER0);
567                 to_virtual = kmap_atomic(to_page, KM_USER1);
568                 memcpy(to_virtual, from_virtual, PAGE_SIZE);
569                 kunmap_atomic(to_virtual, KM_USER1);
570                 kunmap_atomic(from_virtual, KM_USER0);
571                 preempt_enable();
572                 set_page_dirty(to_page);
573                 mark_page_accessed(to_page);
574                 page_cache_release(to_page);
575         }
576
577         ttm_tt_free_alloced_pages(ttm);
578         ttm->swap_storage = swap_storage;
579         ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
580         if (persistant_swap_storage)
581                 ttm->page_flags |= TTM_PAGE_FLAG_PERSISTANT_SWAP;
582
583         return 0;
584 out_err:
585         if (!persistant_swap_storage)
586                 fput(swap_storage);
587
588         return ret;
589 }