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 <linux/printk.h>
42 #include <drm/drm_cache.h>
43 #include <drm/drm_mem_util.h>
44 #include <drm/ttm/ttm_module.h>
45 #include <drm/ttm/ttm_bo_driver.h>
46 #include <drm/ttm/ttm_placement.h>
47 #include <drm/ttm/ttm_page_alloc.h>
48 #include <drm/bus_dma_hacks.h>
49 
50 /**
51  * Allocates storage for pointers to the pages that back the ttm.
52  */
ttm_tt_alloc_page_directory(struct ttm_tt * ttm)53 static void ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
54 {
55 	ttm->pages = drm_calloc_large(ttm->num_pages, sizeof(void*));
56 }
57 
ttm_dma_tt_alloc_page_directory(struct ttm_dma_tt * ttm)58 static void ttm_dma_tt_alloc_page_directory(struct ttm_dma_tt *ttm)
59 {
60 	ttm->ttm.pages = drm_calloc_large(ttm->ttm.num_pages, sizeof(void*));
61 #ifndef __NetBSD__
62 	ttm->dma_address = drm_calloc_large(ttm->ttm.num_pages,
63 					    sizeof(*ttm->dma_address));
64 #endif
65 }
66 
67 #ifdef CONFIG_X86
ttm_tt_set_page_caching(struct page * p,enum ttm_caching_state c_old,enum ttm_caching_state c_new)68 static inline int ttm_tt_set_page_caching(struct page *p,
69 					  enum ttm_caching_state c_old,
70 					  enum ttm_caching_state c_new)
71 {
72 #ifdef __NetBSD__
73 	return 0;
74 #else
75 	int ret = 0;
76 
77 	if (PageHighMem(p))
78 		return 0;
79 
80 	if (c_old != tt_cached) {
81 		/* p isn't in the default caching state, set it to
82 		 * writeback first to free its current memtype. */
83 
84 		ret = set_pages_wb(p, 1);
85 		if (ret)
86 			return ret;
87 	}
88 
89 	if (c_new == tt_wc)
90 		ret = set_memory_wc((unsigned long) page_address(p), 1);
91 	else if (c_new == tt_uncached)
92 		ret = set_pages_uc(p, 1);
93 
94 	return ret;
95 #endif
96 }
97 #else /* CONFIG_X86 */
ttm_tt_set_page_caching(struct page * p,enum ttm_caching_state c_old,enum ttm_caching_state c_new)98 static inline int ttm_tt_set_page_caching(struct page *p,
99 					  enum ttm_caching_state c_old,
100 					  enum ttm_caching_state c_new)
101 {
102 	return 0;
103 }
104 #endif /* CONFIG_X86 */
105 
106 /*
107  * Change caching policy for the linear kernel map
108  * for range of pages in a ttm.
109  */
110 
ttm_tt_set_caching(struct ttm_tt * ttm,enum ttm_caching_state c_state)111 static int ttm_tt_set_caching(struct ttm_tt *ttm,
112 			      enum ttm_caching_state c_state)
113 {
114 	int i, j;
115 	struct page *cur_page;
116 	int ret;
117 
118 	if (ttm->caching_state == c_state)
119 		return 0;
120 
121 	if (ttm->state == tt_unpopulated) {
122 		/* Change caching but don't populate */
123 		ttm->caching_state = c_state;
124 		return 0;
125 	}
126 
127 	if (ttm->caching_state == tt_cached)
128 		drm_clflush_pages(ttm->pages, ttm->num_pages);
129 
130 	for (i = 0; i < ttm->num_pages; ++i) {
131 		cur_page = ttm->pages[i];
132 		if (likely(cur_page != NULL)) {
133 			ret = ttm_tt_set_page_caching(cur_page,
134 						      ttm->caching_state,
135 						      c_state);
136 			if (unlikely(ret != 0))
137 				goto out_err;
138 		}
139 	}
140 
141 	ttm->caching_state = c_state;
142 
143 	return 0;
144 
145 out_err:
146 	for (j = 0; j < i; ++j) {
147 		cur_page = ttm->pages[j];
148 		if (likely(cur_page != NULL)) {
149 			(void)ttm_tt_set_page_caching(cur_page, c_state,
150 						      ttm->caching_state);
151 		}
152 	}
153 
154 	return ret;
155 }
156 
ttm_tt_set_placement_caching(struct ttm_tt * ttm,uint32_t placement)157 int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement)
158 {
159 	enum ttm_caching_state state;
160 
161 	if (placement & TTM_PL_FLAG_WC)
162 		state = tt_wc;
163 	else if (placement & TTM_PL_FLAG_UNCACHED)
164 		state = tt_uncached;
165 	else
166 		state = tt_cached;
167 
168 	return ttm_tt_set_caching(ttm, state);
169 }
170 EXPORT_SYMBOL(ttm_tt_set_placement_caching);
171 
ttm_tt_destroy(struct ttm_tt * ttm)172 void ttm_tt_destroy(struct ttm_tt *ttm)
173 {
174 	if (unlikely(ttm == NULL))
175 		return;
176 
177 	if (ttm->state == tt_bound) {
178 		ttm_tt_unbind(ttm);
179 	}
180 
181 	if (ttm->state == tt_unbound)
182 		ttm_tt_unpopulate(ttm);
183 
184 #ifndef __NetBSD__
185 	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP) &&
186 	    ttm->swap_storage)
187 		fput(ttm->swap_storage);
188 
189 	ttm->swap_storage = NULL;
190 #endif
191 	ttm->func->destroy(ttm);
192 }
193 
ttm_tt_init(struct ttm_tt * ttm,struct ttm_bo_device * bdev,unsigned long size,uint32_t page_flags,struct page * dummy_read_page)194 int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev,
195 		unsigned long size, uint32_t page_flags,
196 		struct page *dummy_read_page)
197 {
198 	ttm->bdev = bdev;
199 	ttm->glob = bdev->glob;
200 	ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
201 	ttm->caching_state = tt_cached;
202 	ttm->page_flags = page_flags;
203 	ttm->dummy_read_page = dummy_read_page;
204 	ttm->state = tt_unpopulated;
205 #ifdef __NetBSD__
206 	ttm->swap_storage = uao_create(roundup2(size, PAGE_SIZE), 0);
207 	uao_set_pgfl(ttm->swap_storage, bus_dmamem_pgfl(bdev->dmat));
208 #else
209 	ttm->swap_storage = NULL;
210 #endif
211 	TAILQ_INIT(&ttm->pglist);
212 
213 	ttm_tt_alloc_page_directory(ttm);
214 	if (!ttm->pages) {
215 		ttm_tt_destroy(ttm);
216 		pr_err("Failed allocating page table\n");
217 		return -ENOMEM;
218 	}
219 	return 0;
220 }
221 EXPORT_SYMBOL(ttm_tt_init);
222 
ttm_tt_fini(struct ttm_tt * ttm)223 void ttm_tt_fini(struct ttm_tt *ttm)
224 {
225 #ifdef __NetBSD__
226 	uao_detach(ttm->swap_storage);
227 	ttm->swap_storage = NULL;
228 #endif
229 	drm_free_large(ttm->pages);
230 	ttm->pages = NULL;
231 }
232 EXPORT_SYMBOL(ttm_tt_fini);
233 
ttm_dma_tt_init(struct ttm_dma_tt * ttm_dma,struct ttm_bo_device * bdev,unsigned long size,uint32_t page_flags,struct page * dummy_read_page)234 int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev,
235 		unsigned long size, uint32_t page_flags,
236 		struct page *dummy_read_page)
237 {
238 	struct ttm_tt *ttm = &ttm_dma->ttm;
239 
240 	ttm->bdev = bdev;
241 	ttm->glob = bdev->glob;
242 	ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
243 	ttm->caching_state = tt_cached;
244 	ttm->page_flags = page_flags;
245 	ttm->dummy_read_page = dummy_read_page;
246 	ttm->state = tt_unpopulated;
247 #ifdef __NetBSD__
248 	ttm->swap_storage = uao_create(roundup2(size, PAGE_SIZE), 0);
249 	uao_set_pgfl(ttm->swap_storage, bus_dmamem_pgfl(bdev->dmat));
250 #else
251 	ttm->swap_storage = NULL;
252 #endif
253 	TAILQ_INIT(&ttm->pglist);
254 
255 	INIT_LIST_HEAD(&ttm_dma->pages_list);
256 	ttm_dma_tt_alloc_page_directory(ttm_dma);
257 #ifdef __NetBSD__
258     {
259 	int error;
260 
261 	if (ttm->num_pages > (SIZE_MAX /
262 		MIN(sizeof(ttm_dma->dma_segs[0]), PAGE_SIZE))) {
263 		error = ENOMEM;
264 		goto fail0;
265 	}
266 	ttm_dma->dma_segs = kmem_alloc((ttm->num_pages *
267 		sizeof(ttm_dma->dma_segs[0])), KM_SLEEP);
268 	error = bus_dmamap_create(ttm->bdev->dmat,
269 	    (ttm->num_pages * PAGE_SIZE), ttm->num_pages, PAGE_SIZE, 0,
270 	    BUS_DMA_WAITOK, &ttm_dma->dma_address);
271 	if (error)
272 		goto fail1;
273 
274 	return 0;
275 
276 fail2: __unused
277 	bus_dmamap_destroy(ttm->bdev->dmat, ttm_dma->dma_address);
278 fail1:	kmem_free(ttm_dma->dma_segs, (ttm->num_pages *
279 		sizeof(ttm_dma->dma_segs[0])));
280 fail0:	KASSERT(error);
281 	ttm_tt_destroy(ttm);
282 	/* XXX errno NetBSD->Linux */
283 	return -error;
284     }
285 #else
286 	if (!ttm->pages || !ttm_dma->dma_address) {
287 		ttm_tt_destroy(ttm);
288 		pr_err("Failed allocating page table\n");
289 		return -ENOMEM;
290 	}
291 	return 0;
292 #endif
293 }
294 EXPORT_SYMBOL(ttm_dma_tt_init);
295 
ttm_dma_tt_fini(struct ttm_dma_tt * ttm_dma)296 void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma)
297 {
298 	struct ttm_tt *ttm = &ttm_dma->ttm;
299 
300 #ifdef __NetBSD__
301 	uao_detach(ttm->swap_storage);
302 	ttm->swap_storage = NULL;
303 #endif
304 	drm_free_large(ttm->pages);
305 	ttm->pages = NULL;
306 #ifdef __NetBSD__
307 	bus_dmamap_destroy(ttm->bdev->dmat, ttm_dma->dma_address);
308 	kmem_free(ttm_dma->dma_segs, (ttm->num_pages *
309 		sizeof(ttm_dma->dma_segs[0])));
310 #else
311 	drm_free_large(ttm_dma->dma_address);
312 	ttm_dma->dma_address = NULL;
313 #endif
314 }
315 EXPORT_SYMBOL(ttm_dma_tt_fini);
316 
ttm_tt_unbind(struct ttm_tt * ttm)317 void ttm_tt_unbind(struct ttm_tt *ttm)
318 {
319 	int ret __diagused;
320 
321 	if (ttm->state == tt_bound) {
322 		ret = ttm->func->unbind(ttm);
323 		BUG_ON(ret);
324 		ttm->state = tt_unbound;
325 	}
326 }
327 
ttm_tt_bind(struct ttm_tt * ttm,struct ttm_mem_reg * bo_mem)328 int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem)
329 {
330 	int ret = 0;
331 
332 	if (!ttm)
333 		return -EINVAL;
334 
335 	if (ttm->state == tt_bound)
336 		return 0;
337 
338 	ret = ttm->bdev->driver->ttm_tt_populate(ttm);
339 	if (ret)
340 		return ret;
341 
342 	ret = ttm->func->bind(ttm, bo_mem);
343 	if (unlikely(ret != 0))
344 		return ret;
345 
346 	ttm->state = tt_bound;
347 
348 	return 0;
349 }
350 EXPORT_SYMBOL(ttm_tt_bind);
351 
352 #ifdef __NetBSD__
353 /*
354  * ttm_tt_wire(ttm)
355  *
356  *	Wire the uvm pages of ttm and fill the ttm page array.  ttm
357  *	must be unpopulated or unbound, and must be marked swapped.
358  *	This does not change either state -- the caller is expected to
359  *	include it among other operations for such a state transition.
360  */
361 int
ttm_tt_wire(struct ttm_tt * ttm)362 ttm_tt_wire(struct ttm_tt *ttm)
363 {
364 	struct uvm_object *uobj = ttm->swap_storage;
365 	struct vm_page *page;
366 	unsigned i;
367 	int error;
368 
369 	KASSERTMSG((ttm->state == tt_unpopulated || ttm->state == tt_unbound),
370 	    "ttm_tt %p must be unpopulated or unbound for wiring,"
371 	    " but state=%d",
372 	    ttm, (int)ttm->state);
373 	KASSERT(ISSET(ttm->page_flags, TTM_PAGE_FLAG_SWAPPED));
374 	KASSERT(uobj != NULL);
375 
376 	error = uvm_obj_wirepages(uobj, 0, (ttm->num_pages << PAGE_SHIFT),
377 	    &ttm->pglist);
378 	if (error)
379 		/* XXX errno NetBSD->Linux */
380 		return -error;
381 
382 	i = 0;
383 	TAILQ_FOREACH(page, &ttm->pglist, pageq.queue) {
384 		KASSERT(i < ttm->num_pages);
385 		KASSERT(ttm->pages[i] == NULL);
386 		ttm->pages[i] = container_of(page, struct page, p_vmp);
387 		i++;
388 	}
389 	KASSERT(i == ttm->num_pages);
390 
391 	/* Success!  */
392 	return 0;
393 }
394 
395 /*
396  * ttm_tt_unwire(ttm)
397  *
398  *	Nullify the ttm page array and unwire the uvm pages of ttm.
399  *	ttm must be unbound and must be marked swapped.  This does not
400  *	change either state -- the caller is expected to include it
401  *	among other operations for such a state transition.
402  */
403 void
ttm_tt_unwire(struct ttm_tt * ttm)404 ttm_tt_unwire(struct ttm_tt *ttm)
405 {
406 	struct uvm_object *uobj = ttm->swap_storage;
407 	unsigned i;
408 
409 	KASSERTMSG((ttm->state == tt_unbound),
410 	    "ttm_tt %p must be unbound for unwiring, but state=%d",
411 	    ttm, (int)ttm->state);
412 	KASSERT(!ISSET(ttm->page_flags, TTM_PAGE_FLAG_SWAPPED));
413 	KASSERT(uobj != NULL);
414 
415 	uvm_obj_unwirepages(uobj, 0, (ttm->num_pages << PAGE_SHIFT));
416 	for (i = 0; i < ttm->num_pages; i++)
417 		ttm->pages[i] = NULL;
418 }
419 #endif
420 
421 #ifndef __NetBSD__
ttm_tt_swapin(struct ttm_tt * ttm)422 int ttm_tt_swapin(struct ttm_tt *ttm)
423 {
424 	struct address_space *swap_space;
425 	struct file *swap_storage;
426 	struct page *from_page;
427 	struct page *to_page;
428 	int i;
429 	int ret = -ENOMEM;
430 
431 	swap_storage = ttm->swap_storage;
432 	BUG_ON(swap_storage == NULL);
433 
434 	swap_space = file_inode(swap_storage)->i_mapping;
435 
436 	for (i = 0; i < ttm->num_pages; ++i) {
437 		from_page = shmem_read_mapping_page(swap_space, i);
438 		if (IS_ERR(from_page)) {
439 			ret = PTR_ERR(from_page);
440 			goto out_err;
441 		}
442 		to_page = ttm->pages[i];
443 		if (unlikely(to_page == NULL))
444 			goto out_err;
445 
446 		copy_highpage(to_page, from_page);
447 		page_cache_release(from_page);
448 	}
449 
450 	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP))
451 		fput(swap_storage);
452 	ttm->swap_storage = NULL;
453 	ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
454 
455 	return 0;
456 out_err:
457 	return ret;
458 }
459 #endif
460 
ttm_tt_swapout(struct ttm_tt * ttm,struct file * persistent_swap_storage)461 int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistent_swap_storage)
462 {
463 #ifdef __NetBSD__
464 
465 	KASSERTMSG((ttm->state == tt_unpopulated || ttm->state == tt_unbound),
466 	    "ttm_tt %p must be unpopulated or unbound for swapout,"
467 	    " but state=%d",
468 	    ttm, (int)ttm->state);
469 	KASSERTMSG((ttm->caching_state == tt_cached),
470 	    "ttm_tt %p must be cached for swapout, but caching_state=%d",
471 	    ttm, (int)ttm->caching_state);
472 	KASSERT(persistent_swap_storage == NULL);
473 
474 	ttm->bdev->driver->ttm_tt_swapout(ttm);
475 	return 0;
476 #else
477 	struct address_space *swap_space;
478 	struct file *swap_storage;
479 	struct page *from_page;
480 	struct page *to_page;
481 	int i;
482 	int ret = -ENOMEM;
483 
484 	BUG_ON(ttm->state != tt_unbound && ttm->state != tt_unpopulated);
485 	BUG_ON(ttm->caching_state != tt_cached);
486 
487 	if (!persistent_swap_storage) {
488 		swap_storage = shmem_file_setup("ttm swap",
489 						ttm->num_pages << PAGE_SHIFT,
490 						0);
491 		if (unlikely(IS_ERR(swap_storage))) {
492 			pr_err("Failed allocating swap storage\n");
493 			return PTR_ERR(swap_storage);
494 		}
495 	} else
496 		swap_storage = persistent_swap_storage;
497 
498 	swap_space = file_inode(swap_storage)->i_mapping;
499 
500 	for (i = 0; i < ttm->num_pages; ++i) {
501 		from_page = ttm->pages[i];
502 		if (unlikely(from_page == NULL))
503 			continue;
504 		to_page = shmem_read_mapping_page(swap_space, i);
505 		if (unlikely(IS_ERR(to_page))) {
506 			ret = PTR_ERR(to_page);
507 			goto out_err;
508 		}
509 		copy_highpage(to_page, from_page);
510 		set_page_dirty(to_page);
511 		mark_page_accessed(to_page);
512 		page_cache_release(to_page);
513 	}
514 
515 	ttm_tt_unpopulate(ttm);
516 	ttm->swap_storage = swap_storage;
517 	ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
518 	if (persistent_swap_storage)
519 		ttm->page_flags |= TTM_PAGE_FLAG_PERSISTENT_SWAP;
520 
521 	return 0;
522 out_err:
523 	if (!persistent_swap_storage)
524 		fput(swap_storage);
525 
526 	return ret;
527 #endif
528 }
529 
ttm_tt_clear_mapping(struct ttm_tt * ttm)530 static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
531 {
532 #ifndef __NetBSD__
533 	pgoff_t i;
534 	struct page **page = ttm->pages;
535 
536 	if (ttm->page_flags & TTM_PAGE_FLAG_SG)
537 		return;
538 
539 	for (i = 0; i < ttm->num_pages; ++i) {
540 		(*page)->mapping = NULL;
541 		(*page++)->index = 0;
542 	}
543 #endif
544 }
545 
ttm_tt_unpopulate(struct ttm_tt * ttm)546 void ttm_tt_unpopulate(struct ttm_tt *ttm)
547 {
548 	if (ttm->state == tt_unpopulated)
549 		return;
550 
551 	ttm_tt_clear_mapping(ttm);
552 	ttm->bdev->driver->ttm_tt_unpopulate(ttm);
553 }
554