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31
32#define pr_fmt(fmt) "[TTM] " fmt
33
34#include <linux/sched.h>
35#include <linux/shmem_fs.h>
36#include <linux/file.h>
37#include <drm/drm_cache.h>
38#include <drm/ttm/ttm_bo_driver.h>
39
40#include "ttm_module.h"
41
42static unsigned long ttm_pages_limit;
43
44MODULE_PARM_DESC(pages_limit, "Limit for the allocated pages");
45module_param_named(pages_limit, ttm_pages_limit, ulong, 0644);
46
47static unsigned long ttm_dma32_pages_limit;
48
49MODULE_PARM_DESC(dma32_pages_limit, "Limit for the allocated DMA32 pages");
50module_param_named(dma32_pages_limit, ttm_dma32_pages_limit, ulong, 0644);
51
52static atomic_long_t ttm_pages_allocated;
53static atomic_long_t ttm_dma32_pages_allocated;
54
55
56
57
58int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc)
59{
60 struct ttm_device *bdev = bo->bdev;
61 uint32_t page_flags = 0;
62
63 dma_resv_assert_held(bo->base.resv);
64
65 if (bo->ttm)
66 return 0;
67
68 switch (bo->type) {
69 case ttm_bo_type_device:
70 if (zero_alloc)
71 page_flags |= TTM_PAGE_FLAG_ZERO_ALLOC;
72 break;
73 case ttm_bo_type_kernel:
74 break;
75 case ttm_bo_type_sg:
76 page_flags |= TTM_PAGE_FLAG_SG;
77 break;
78 default:
79 pr_err("Illegal buffer object type\n");
80 return -EINVAL;
81 }
82
83 bo->ttm = bdev->funcs->ttm_tt_create(bo, page_flags);
84 if (unlikely(bo->ttm == NULL))
85 return -ENOMEM;
86
87 return 0;
88}
89
90
91
92
93static int ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
94{
95 ttm->pages = kvmalloc_array(ttm->num_pages, sizeof(void*),
96 GFP_KERNEL | __GFP_ZERO);
97 if (!ttm->pages)
98 return -ENOMEM;
99 return 0;
100}
101
102static int ttm_dma_tt_alloc_page_directory(struct ttm_tt *ttm)
103{
104 ttm->pages = kvmalloc_array(ttm->num_pages,
105 sizeof(*ttm->pages) +
106 sizeof(*ttm->dma_address),
107 GFP_KERNEL | __GFP_ZERO);
108 if (!ttm->pages)
109 return -ENOMEM;
110
111 ttm->dma_address = (void *)(ttm->pages + ttm->num_pages);
112 return 0;
113}
114
115static int ttm_sg_tt_alloc_page_directory(struct ttm_tt *ttm)
116{
117 ttm->dma_address = kvmalloc_array(ttm->num_pages,
118 sizeof(*ttm->dma_address),
119 GFP_KERNEL | __GFP_ZERO);
120 if (!ttm->dma_address)
121 return -ENOMEM;
122 return 0;
123}
124
125void ttm_tt_destroy_common(struct ttm_device *bdev, struct ttm_tt *ttm)
126{
127 ttm_tt_unpopulate(bdev, ttm);
128
129 if (ttm->swap_storage)
130 fput(ttm->swap_storage);
131
132 ttm->swap_storage = NULL;
133}
134EXPORT_SYMBOL(ttm_tt_destroy_common);
135
136void ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *ttm)
137{
138 bdev->funcs->ttm_tt_destroy(bdev, ttm);
139}
140
141static void ttm_tt_init_fields(struct ttm_tt *ttm,
142 struct ttm_buffer_object *bo,
143 uint32_t page_flags,
144 enum ttm_caching caching)
145{
146 ttm->num_pages = PAGE_ALIGN(bo->base.size) >> PAGE_SHIFT;
147 ttm->caching = ttm_cached;
148 ttm->page_flags = page_flags;
149 ttm->dma_address = NULL;
150 ttm->swap_storage = NULL;
151 ttm->sg = bo->sg;
152 ttm->caching = caching;
153}
154
155int ttm_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
156 uint32_t page_flags, enum ttm_caching caching)
157{
158 ttm_tt_init_fields(ttm, bo, page_flags, caching);
159
160 if (ttm_tt_alloc_page_directory(ttm)) {
161 pr_err("Failed allocating page table\n");
162 return -ENOMEM;
163 }
164 return 0;
165}
166EXPORT_SYMBOL(ttm_tt_init);
167
168void ttm_tt_fini(struct ttm_tt *ttm)
169{
170 if (ttm->pages)
171 kvfree(ttm->pages);
172 else
173 kvfree(ttm->dma_address);
174 ttm->pages = NULL;
175 ttm->dma_address = NULL;
176}
177EXPORT_SYMBOL(ttm_tt_fini);
178
179int ttm_sg_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
180 uint32_t page_flags, enum ttm_caching caching)
181{
182 int ret;
183
184 ttm_tt_init_fields(ttm, bo, page_flags, caching);
185
186 if (page_flags & TTM_PAGE_FLAG_SG)
187 ret = ttm_sg_tt_alloc_page_directory(ttm);
188 else
189 ret = ttm_dma_tt_alloc_page_directory(ttm);
190 if (ret) {
191 pr_err("Failed allocating page table\n");
192 return -ENOMEM;
193 }
194 return 0;
195}
196EXPORT_SYMBOL(ttm_sg_tt_init);
197
198int ttm_tt_swapin(struct ttm_tt *ttm)
199{
200 struct address_space *swap_space;
201 struct file *swap_storage;
202 struct page *from_page;
203 struct page *to_page;
204 gfp_t gfp_mask;
205 int i, ret;
206
207 swap_storage = ttm->swap_storage;
208 BUG_ON(swap_storage == NULL);
209
210 swap_space = swap_storage->f_mapping;
211 gfp_mask = mapping_gfp_mask(swap_space);
212
213 for (i = 0; i < ttm->num_pages; ++i) {
214 from_page = shmem_read_mapping_page_gfp(swap_space, i,
215 gfp_mask);
216 if (IS_ERR(from_page)) {
217 ret = PTR_ERR(from_page);
218 goto out_err;
219 }
220 to_page = ttm->pages[i];
221 if (unlikely(to_page == NULL)) {
222 ret = -ENOMEM;
223 goto out_err;
224 }
225
226 copy_highpage(to_page, from_page);
227 put_page(from_page);
228 }
229
230 fput(swap_storage);
231 ttm->swap_storage = NULL;
232 ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
233
234 return 0;
235
236out_err:
237 return ret;
238}
239
240
241
242
243
244
245
246
247
248
249
250int ttm_tt_swapout(struct ttm_device *bdev, struct ttm_tt *ttm,
251 gfp_t gfp_flags)
252{
253 loff_t size = (loff_t)ttm->num_pages << PAGE_SHIFT;
254 struct address_space *swap_space;
255 struct file *swap_storage;
256 struct page *from_page;
257 struct page *to_page;
258 int i, ret;
259
260 swap_storage = shmem_file_setup("ttm swap", size, 0);
261 if (IS_ERR(swap_storage)) {
262 pr_err("Failed allocating swap storage\n");
263 return PTR_ERR(swap_storage);
264 }
265
266 swap_space = swap_storage->f_mapping;
267 gfp_flags &= mapping_gfp_mask(swap_space);
268
269 for (i = 0; i < ttm->num_pages; ++i) {
270 from_page = ttm->pages[i];
271 if (unlikely(from_page == NULL))
272 continue;
273
274 to_page = shmem_read_mapping_page_gfp(swap_space, i, gfp_flags);
275 if (IS_ERR(to_page)) {
276 ret = PTR_ERR(to_page);
277 goto out_err;
278 }
279 copy_highpage(to_page, from_page);
280 set_page_dirty(to_page);
281 mark_page_accessed(to_page);
282 put_page(to_page);
283 }
284
285 ttm_tt_unpopulate(bdev, ttm);
286 ttm->swap_storage = swap_storage;
287 ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
288
289 return ttm->num_pages;
290
291out_err:
292 fput(swap_storage);
293
294 return ret;
295}
296
297static void ttm_tt_add_mapping(struct ttm_device *bdev, struct ttm_tt *ttm)
298{
299 pgoff_t i;
300
301 if (ttm->page_flags & TTM_PAGE_FLAG_SG)
302 return;
303
304 for (i = 0; i < ttm->num_pages; ++i)
305 ttm->pages[i]->mapping = bdev->dev_mapping;
306}
307
308int ttm_tt_populate(struct ttm_device *bdev,
309 struct ttm_tt *ttm, struct ttm_operation_ctx *ctx)
310{
311 int ret;
312
313 if (!ttm)
314 return -EINVAL;
315
316 if (ttm_tt_is_populated(ttm))
317 return 0;
318
319 if (!(ttm->page_flags & TTM_PAGE_FLAG_SG)) {
320 atomic_long_add(ttm->num_pages, &ttm_pages_allocated);
321 if (bdev->pool.use_dma32)
322 atomic_long_add(ttm->num_pages,
323 &ttm_dma32_pages_allocated);
324 }
325
326 while (atomic_long_read(&ttm_pages_allocated) > ttm_pages_limit ||
327 atomic_long_read(&ttm_dma32_pages_allocated) >
328 ttm_dma32_pages_limit) {
329
330 ret = ttm_global_swapout(ctx, GFP_KERNEL);
331 if (ret == 0)
332 break;
333 if (ret < 0)
334 goto error;
335 }
336
337 if (bdev->funcs->ttm_tt_populate)
338 ret = bdev->funcs->ttm_tt_populate(bdev, ttm, ctx);
339 else
340 ret = ttm_pool_alloc(&bdev->pool, ttm, ctx);
341 if (ret)
342 goto error;
343
344 ttm_tt_add_mapping(bdev, ttm);
345 ttm->page_flags |= TTM_PAGE_FLAG_PRIV_POPULATED;
346 if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
347 ret = ttm_tt_swapin(ttm);
348 if (unlikely(ret != 0)) {
349 ttm_tt_unpopulate(bdev, ttm);
350 return ret;
351 }
352 }
353
354 return 0;
355
356error:
357 if (!(ttm->page_flags & TTM_PAGE_FLAG_SG)) {
358 atomic_long_sub(ttm->num_pages, &ttm_pages_allocated);
359 if (bdev->pool.use_dma32)
360 atomic_long_sub(ttm->num_pages,
361 &ttm_dma32_pages_allocated);
362 }
363 return ret;
364}
365EXPORT_SYMBOL(ttm_tt_populate);
366
367static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
368{
369 pgoff_t i;
370 struct page **page = ttm->pages;
371
372 if (ttm->page_flags & TTM_PAGE_FLAG_SG)
373 return;
374
375 for (i = 0; i < ttm->num_pages; ++i) {
376 (*page)->mapping = NULL;
377 (*page++)->index = 0;
378 }
379}
380
381void ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm)
382{
383 if (!ttm_tt_is_populated(ttm))
384 return;
385
386 ttm_tt_clear_mapping(ttm);
387 if (bdev->funcs->ttm_tt_unpopulate)
388 bdev->funcs->ttm_tt_unpopulate(bdev, ttm);
389 else
390 ttm_pool_free(&bdev->pool, ttm);
391
392 if (!(ttm->page_flags & TTM_PAGE_FLAG_SG)) {
393 atomic_long_sub(ttm->num_pages, &ttm_pages_allocated);
394 if (bdev->pool.use_dma32)
395 atomic_long_sub(ttm->num_pages,
396 &ttm_dma32_pages_allocated);
397 }
398
399 ttm->page_flags &= ~TTM_PAGE_FLAG_PRIV_POPULATED;
400}
401
402#ifdef CONFIG_DEBUG_FS
403
404
405static int ttm_tt_debugfs_shrink_show(struct seq_file *m, void *data)
406{
407 struct ttm_operation_ctx ctx = { false, false };
408
409 seq_printf(m, "%d\n", ttm_global_swapout(&ctx, GFP_KERNEL));
410 return 0;
411}
412DEFINE_SHOW_ATTRIBUTE(ttm_tt_debugfs_shrink);
413
414#endif
415
416
417
418
419
420
421
422void ttm_tt_mgr_init(unsigned long num_pages, unsigned long num_dma32_pages)
423{
424#ifdef CONFIG_DEBUG_FS
425 debugfs_create_file("tt_shrink", 0400, ttm_debugfs_root, NULL,
426 &ttm_tt_debugfs_shrink_fops);
427#endif
428
429 if (!ttm_pages_limit)
430 ttm_pages_limit = num_pages;
431
432 if (!ttm_dma32_pages_limit)
433 ttm_dma32_pages_limit = num_dma32_pages;
434}
435
436static void ttm_kmap_iter_tt_map_local(struct ttm_kmap_iter *iter,
437 struct dma_buf_map *dmap,
438 pgoff_t i)
439{
440 struct ttm_kmap_iter_tt *iter_tt =
441 container_of(iter, typeof(*iter_tt), base);
442
443 dma_buf_map_set_vaddr(dmap, kmap_local_page_prot(iter_tt->tt->pages[i],
444 iter_tt->prot));
445}
446
447static void ttm_kmap_iter_tt_unmap_local(struct ttm_kmap_iter *iter,
448 struct dma_buf_map *map)
449{
450 kunmap_local(map->vaddr);
451}
452
453static const struct ttm_kmap_iter_ops ttm_kmap_iter_tt_ops = {
454 .map_local = ttm_kmap_iter_tt_map_local,
455 .unmap_local = ttm_kmap_iter_tt_unmap_local,
456 .maps_tt = true,
457};
458
459
460
461
462
463
464
465
466struct ttm_kmap_iter *
467ttm_kmap_iter_tt_init(struct ttm_kmap_iter_tt *iter_tt,
468 struct ttm_tt *tt)
469{
470 iter_tt->base.ops = &ttm_kmap_iter_tt_ops;
471 iter_tt->tt = tt;
472 if (tt)
473 iter_tt->prot = ttm_prot_from_caching(tt->caching, PAGE_KERNEL);
474 else
475 iter_tt->prot = PAGE_KERNEL;
476
477 return &iter_tt->base;
478}
479EXPORT_SYMBOL(ttm_kmap_iter_tt_init);
480