xfs: preserve DIFLAG2_NREXT64 when setting other inode attributes
[platform/kernel/linux-starfive.git] / drivers / gpu / drm / ttm / ttm_resource.c
1 /*
2  * Copyright 2020 Advanced Micro Devices, Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors: Christian König
23  */
24
25 #include <linux/iosys-map.h>
26 #include <linux/io-mapping.h>
27 #include <linux/scatterlist.h>
28
29 #include <drm/ttm/ttm_resource.h>
30 #include <drm/ttm/ttm_bo_driver.h>
31
32 /**
33  * ttm_lru_bulk_move_init - initialize a bulk move structure
34  * @bulk: the structure to init
35  *
36  * For now just memset the structure to zero.
37  */
38 void ttm_lru_bulk_move_init(struct ttm_lru_bulk_move *bulk)
39 {
40         memset(bulk, 0, sizeof(*bulk));
41 }
42 EXPORT_SYMBOL(ttm_lru_bulk_move_init);
43
44 /**
45  * ttm_lru_bulk_move_tail - bulk move range of resources to the LRU tail.
46  *
47  * @bulk: bulk move structure
48  *
49  * Bulk move BOs to the LRU tail, only valid to use when driver makes sure that
50  * resource order never changes. Should be called with &ttm_device.lru_lock held.
51  */
52 void ttm_lru_bulk_move_tail(struct ttm_lru_bulk_move *bulk)
53 {
54         unsigned i, j;
55
56         for (i = 0; i < TTM_NUM_MEM_TYPES; ++i) {
57                 for (j = 0; j < TTM_MAX_BO_PRIORITY; ++j) {
58                         struct ttm_lru_bulk_move_pos *pos = &bulk->pos[i][j];
59                         struct ttm_resource_manager *man;
60
61                         if (!pos->first)
62                                 continue;
63
64                         lockdep_assert_held(&pos->first->bo->bdev->lru_lock);
65                         dma_resv_assert_held(pos->first->bo->base.resv);
66                         dma_resv_assert_held(pos->last->bo->base.resv);
67
68                         man = ttm_manager_type(pos->first->bo->bdev, i);
69                         list_bulk_move_tail(&man->lru[j], &pos->first->lru,
70                                             &pos->last->lru);
71                 }
72         }
73 }
74 EXPORT_SYMBOL(ttm_lru_bulk_move_tail);
75
76 /* Return the bulk move pos object for this resource */
77 static struct ttm_lru_bulk_move_pos *
78 ttm_lru_bulk_move_pos(struct ttm_lru_bulk_move *bulk, struct ttm_resource *res)
79 {
80         return &bulk->pos[res->mem_type][res->bo->priority];
81 }
82
83 /* Move the resource to the tail of the bulk move range */
84 static void ttm_lru_bulk_move_pos_tail(struct ttm_lru_bulk_move_pos *pos,
85                                        struct ttm_resource *res)
86 {
87         if (pos->last != res) {
88                 list_move(&res->lru, &pos->last->lru);
89                 pos->last = res;
90         }
91 }
92
93 /* Add the resource to a bulk_move cursor */
94 void ttm_lru_bulk_move_add(struct ttm_lru_bulk_move *bulk,
95                            struct ttm_resource *res)
96 {
97         struct ttm_lru_bulk_move_pos *pos = ttm_lru_bulk_move_pos(bulk, res);
98
99         if (!pos->first) {
100                 pos->first = res;
101                 pos->last = res;
102         } else {
103                 ttm_lru_bulk_move_pos_tail(pos, res);
104         }
105 }
106
107 /* Remove the resource from a bulk_move range */
108 void ttm_lru_bulk_move_del(struct ttm_lru_bulk_move *bulk,
109                            struct ttm_resource *res)
110 {
111         struct ttm_lru_bulk_move_pos *pos = ttm_lru_bulk_move_pos(bulk, res);
112
113         if (unlikely(pos->first == res && pos->last == res)) {
114                 pos->first = NULL;
115                 pos->last = NULL;
116         } else if (pos->first == res) {
117                 pos->first = list_next_entry(res, lru);
118         } else if (pos->last == res) {
119                 pos->last = list_prev_entry(res, lru);
120         } else {
121                 list_move(&res->lru, &pos->last->lru);
122         }
123 }
124
125 /* Move a resource to the LRU or bulk tail */
126 void ttm_resource_move_to_lru_tail(struct ttm_resource *res)
127 {
128         struct ttm_buffer_object *bo = res->bo;
129         struct ttm_device *bdev = bo->bdev;
130
131         lockdep_assert_held(&bo->bdev->lru_lock);
132
133         if (bo->pin_count) {
134                 list_move_tail(&res->lru, &bdev->pinned);
135
136         } else  if (bo->bulk_move) {
137                 struct ttm_lru_bulk_move_pos *pos =
138                         ttm_lru_bulk_move_pos(bo->bulk_move, res);
139
140                 ttm_lru_bulk_move_pos_tail(pos, res);
141         } else {
142                 struct ttm_resource_manager *man;
143
144                 man = ttm_manager_type(bdev, res->mem_type);
145                 list_move_tail(&res->lru, &man->lru[bo->priority]);
146         }
147 }
148
149 /**
150  * ttm_resource_init - resource object constructure
151  * @bo: buffer object this resources is allocated for
152  * @place: placement of the resource
153  * @res: the resource object to inistilize
154  *
155  * Initialize a new resource object. Counterpart of ttm_resource_fini().
156  */
157 void ttm_resource_init(struct ttm_buffer_object *bo,
158                        const struct ttm_place *place,
159                        struct ttm_resource *res)
160 {
161         struct ttm_resource_manager *man;
162
163         res->start = 0;
164         res->num_pages = PFN_UP(bo->base.size);
165         res->mem_type = place->mem_type;
166         res->placement = place->flags;
167         res->bus.addr = NULL;
168         res->bus.offset = 0;
169         res->bus.is_iomem = false;
170         res->bus.caching = ttm_cached;
171         res->bo = bo;
172         INIT_LIST_HEAD(&res->lru);
173
174         man = ttm_manager_type(bo->bdev, place->mem_type);
175         spin_lock(&bo->bdev->lru_lock);
176         man->usage += res->num_pages << PAGE_SHIFT;
177         if (bo->bulk_move)
178                 ttm_lru_bulk_move_add(bo->bulk_move, res);
179         else
180                 ttm_resource_move_to_lru_tail(res);
181         spin_unlock(&bo->bdev->lru_lock);
182 }
183 EXPORT_SYMBOL(ttm_resource_init);
184
185 /**
186  * ttm_resource_fini - resource destructor
187  * @man: the resource manager this resource belongs to
188  * @res: the resource to clean up
189  *
190  * Should be used by resource manager backends to clean up the TTM resource
191  * objects before freeing the underlying structure. Makes sure the resource is
192  * removed from the LRU before destruction.
193  * Counterpart of ttm_resource_init().
194  */
195 void ttm_resource_fini(struct ttm_resource_manager *man,
196                        struct ttm_resource *res)
197 {
198         struct ttm_device *bdev = man->bdev;
199
200         spin_lock(&bdev->lru_lock);
201         list_del_init(&res->lru);
202         man->usage -= res->num_pages << PAGE_SHIFT;
203         spin_unlock(&bdev->lru_lock);
204 }
205 EXPORT_SYMBOL(ttm_resource_fini);
206
207 int ttm_resource_alloc(struct ttm_buffer_object *bo,
208                        const struct ttm_place *place,
209                        struct ttm_resource **res_ptr)
210 {
211         struct ttm_resource_manager *man =
212                 ttm_manager_type(bo->bdev, place->mem_type);
213
214         return man->func->alloc(man, bo, place, res_ptr);
215 }
216
217 void ttm_resource_free(struct ttm_buffer_object *bo, struct ttm_resource **res)
218 {
219         struct ttm_resource_manager *man;
220
221         if (!*res)
222                 return;
223
224         if (bo->bulk_move) {
225                 spin_lock(&bo->bdev->lru_lock);
226                 ttm_lru_bulk_move_del(bo->bulk_move, *res);
227                 spin_unlock(&bo->bdev->lru_lock);
228         }
229
230         man = ttm_manager_type(bo->bdev, (*res)->mem_type);
231         man->func->free(man, *res);
232         *res = NULL;
233 }
234 EXPORT_SYMBOL(ttm_resource_free);
235
236 static bool ttm_resource_places_compat(struct ttm_resource *res,
237                                        const struct ttm_place *places,
238                                        unsigned num_placement)
239 {
240         unsigned i;
241
242         if (res->placement & TTM_PL_FLAG_TEMPORARY)
243                 return false;
244
245         for (i = 0; i < num_placement; i++) {
246                 const struct ttm_place *heap = &places[i];
247
248                 if (res->start < heap->fpfn || (heap->lpfn &&
249                     (res->start + res->num_pages) > heap->lpfn))
250                         continue;
251
252                 if ((res->mem_type == heap->mem_type) &&
253                     (!(heap->flags & TTM_PL_FLAG_CONTIGUOUS) ||
254                      (res->placement & TTM_PL_FLAG_CONTIGUOUS)))
255                         return true;
256         }
257         return false;
258 }
259
260 /**
261  * ttm_resource_compat - check if resource is compatible with placement
262  *
263  * @res: the resource to check
264  * @placement: the placement to check against
265  *
266  * Returns true if the placement is compatible.
267  */
268 bool ttm_resource_compat(struct ttm_resource *res,
269                          struct ttm_placement *placement)
270 {
271         if (ttm_resource_places_compat(res, placement->placement,
272                                        placement->num_placement))
273                 return true;
274
275         if ((placement->busy_placement != placement->placement ||
276              placement->num_busy_placement > placement->num_placement) &&
277             ttm_resource_places_compat(res, placement->busy_placement,
278                                        placement->num_busy_placement))
279                 return true;
280
281         return false;
282 }
283 EXPORT_SYMBOL(ttm_resource_compat);
284
285 void ttm_resource_set_bo(struct ttm_resource *res,
286                          struct ttm_buffer_object *bo)
287 {
288         spin_lock(&bo->bdev->lru_lock);
289         res->bo = bo;
290         spin_unlock(&bo->bdev->lru_lock);
291 }
292
293 /**
294  * ttm_resource_manager_init
295  *
296  * @man: memory manager object to init
297  * @bdev: ttm device this manager belongs to
298  * @size: size of managed resources in arbitrary units
299  *
300  * Initialise core parts of a manager object.
301  */
302 void ttm_resource_manager_init(struct ttm_resource_manager *man,
303                                struct ttm_device *bdev,
304                                uint64_t size)
305 {
306         unsigned i;
307
308         spin_lock_init(&man->move_lock);
309         man->bdev = bdev;
310         man->size = size;
311         man->usage = 0;
312
313         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i)
314                 INIT_LIST_HEAD(&man->lru[i]);
315         man->move = NULL;
316 }
317 EXPORT_SYMBOL(ttm_resource_manager_init);
318
319 /*
320  * ttm_resource_manager_evict_all
321  *
322  * @bdev - device to use
323  * @man - manager to use
324  *
325  * Evict all the objects out of a memory manager until it is empty.
326  * Part of memory manager cleanup sequence.
327  */
328 int ttm_resource_manager_evict_all(struct ttm_device *bdev,
329                                    struct ttm_resource_manager *man)
330 {
331         struct ttm_operation_ctx ctx = {
332                 .interruptible = false,
333                 .no_wait_gpu = false,
334                 .force_alloc = true
335         };
336         struct dma_fence *fence;
337         int ret;
338         unsigned i;
339
340         /*
341          * Can't use standard list traversal since we're unlocking.
342          */
343
344         spin_lock(&bdev->lru_lock);
345         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
346                 while (!list_empty(&man->lru[i])) {
347                         spin_unlock(&bdev->lru_lock);
348                         ret = ttm_mem_evict_first(bdev, man, NULL, &ctx,
349                                                   NULL);
350                         if (ret)
351                                 return ret;
352                         spin_lock(&bdev->lru_lock);
353                 }
354         }
355         spin_unlock(&bdev->lru_lock);
356
357         spin_lock(&man->move_lock);
358         fence = dma_fence_get(man->move);
359         spin_unlock(&man->move_lock);
360
361         if (fence) {
362                 ret = dma_fence_wait(fence, false);
363                 dma_fence_put(fence);
364                 if (ret)
365                         return ret;
366         }
367
368         return 0;
369 }
370 EXPORT_SYMBOL(ttm_resource_manager_evict_all);
371
372 /**
373  * ttm_resource_manager_usage
374  *
375  * @man: A memory manager object.
376  *
377  * Return how many resources are currently used.
378  */
379 uint64_t ttm_resource_manager_usage(struct ttm_resource_manager *man)
380 {
381         uint64_t usage;
382
383         spin_lock(&man->bdev->lru_lock);
384         usage = man->usage;
385         spin_unlock(&man->bdev->lru_lock);
386         return usage;
387 }
388 EXPORT_SYMBOL(ttm_resource_manager_usage);
389
390 /**
391  * ttm_resource_manager_debug
392  *
393  * @man: manager type to dump.
394  * @p: printer to use for debug.
395  */
396 void ttm_resource_manager_debug(struct ttm_resource_manager *man,
397                                 struct drm_printer *p)
398 {
399         drm_printf(p, "  use_type: %d\n", man->use_type);
400         drm_printf(p, "  use_tt: %d\n", man->use_tt);
401         drm_printf(p, "  size: %llu\n", man->size);
402         drm_printf(p, "  usage: %llu\n", ttm_resource_manager_usage(man));
403         if (man->func->debug)
404                 man->func->debug(man, p);
405 }
406 EXPORT_SYMBOL(ttm_resource_manager_debug);
407
408 /**
409  * ttm_resource_manager_first
410  *
411  * @man: resource manager to iterate over
412  * @cursor: cursor to record the position
413  *
414  * Returns the first resource from the resource manager.
415  */
416 struct ttm_resource *
417 ttm_resource_manager_first(struct ttm_resource_manager *man,
418                            struct ttm_resource_cursor *cursor)
419 {
420         struct ttm_resource *res;
421
422         lockdep_assert_held(&man->bdev->lru_lock);
423
424         for (cursor->priority = 0; cursor->priority < TTM_MAX_BO_PRIORITY;
425              ++cursor->priority)
426                 list_for_each_entry(res, &man->lru[cursor->priority], lru)
427                         return res;
428
429         return NULL;
430 }
431
432 /**
433  * ttm_resource_manager_next
434  *
435  * @man: resource manager to iterate over
436  * @cursor: cursor to record the position
437  * @res: the current resource pointer
438  *
439  * Returns the next resource from the resource manager.
440  */
441 struct ttm_resource *
442 ttm_resource_manager_next(struct ttm_resource_manager *man,
443                           struct ttm_resource_cursor *cursor,
444                           struct ttm_resource *res)
445 {
446         lockdep_assert_held(&man->bdev->lru_lock);
447
448         list_for_each_entry_continue(res, &man->lru[cursor->priority], lru)
449                 return res;
450
451         for (++cursor->priority; cursor->priority < TTM_MAX_BO_PRIORITY;
452              ++cursor->priority)
453                 list_for_each_entry(res, &man->lru[cursor->priority], lru)
454                         return res;
455
456         return NULL;
457 }
458
459 static void ttm_kmap_iter_iomap_map_local(struct ttm_kmap_iter *iter,
460                                           struct iosys_map *dmap,
461                                           pgoff_t i)
462 {
463         struct ttm_kmap_iter_iomap *iter_io =
464                 container_of(iter, typeof(*iter_io), base);
465         void __iomem *addr;
466
467 retry:
468         while (i >= iter_io->cache.end) {
469                 iter_io->cache.sg = iter_io->cache.sg ?
470                         sg_next(iter_io->cache.sg) : iter_io->st->sgl;
471                 iter_io->cache.i = iter_io->cache.end;
472                 iter_io->cache.end += sg_dma_len(iter_io->cache.sg) >>
473                         PAGE_SHIFT;
474                 iter_io->cache.offs = sg_dma_address(iter_io->cache.sg) -
475                         iter_io->start;
476         }
477
478         if (i < iter_io->cache.i) {
479                 iter_io->cache.end = 0;
480                 iter_io->cache.sg = NULL;
481                 goto retry;
482         }
483
484         addr = io_mapping_map_local_wc(iter_io->iomap, iter_io->cache.offs +
485                                        (((resource_size_t)i - iter_io->cache.i)
486                                         << PAGE_SHIFT));
487         iosys_map_set_vaddr_iomem(dmap, addr);
488 }
489
490 static void ttm_kmap_iter_iomap_unmap_local(struct ttm_kmap_iter *iter,
491                                             struct iosys_map *map)
492 {
493         io_mapping_unmap_local(map->vaddr_iomem);
494 }
495
496 static const struct ttm_kmap_iter_ops ttm_kmap_iter_io_ops = {
497         .map_local =  ttm_kmap_iter_iomap_map_local,
498         .unmap_local = ttm_kmap_iter_iomap_unmap_local,
499         .maps_tt = false,
500 };
501
502 /**
503  * ttm_kmap_iter_iomap_init - Initialize a struct ttm_kmap_iter_iomap
504  * @iter_io: The struct ttm_kmap_iter_iomap to initialize.
505  * @iomap: The struct io_mapping representing the underlying linear io_memory.
506  * @st: sg_table into @iomap, representing the memory of the struct
507  * ttm_resource.
508  * @start: Offset that needs to be subtracted from @st to make
509  * sg_dma_address(st->sgl) - @start == 0 for @iomap start.
510  *
511  * Return: Pointer to the embedded struct ttm_kmap_iter.
512  */
513 struct ttm_kmap_iter *
514 ttm_kmap_iter_iomap_init(struct ttm_kmap_iter_iomap *iter_io,
515                          struct io_mapping *iomap,
516                          struct sg_table *st,
517                          resource_size_t start)
518 {
519         iter_io->base.ops = &ttm_kmap_iter_io_ops;
520         iter_io->iomap = iomap;
521         iter_io->st = st;
522         iter_io->start = start;
523         memset(&iter_io->cache, 0, sizeof(iter_io->cache));
524
525         return &iter_io->base;
526 }
527 EXPORT_SYMBOL(ttm_kmap_iter_iomap_init);
528
529 /**
530  * DOC: Linear io iterator
531  *
532  * This code should die in the not too near future. Best would be if we could
533  * make io-mapping use memremap for all io memory, and have memremap
534  * implement a kmap_local functionality. We could then strip a huge amount of
535  * code. These linear io iterators are implemented to mimic old functionality,
536  * and they don't use kmap_local semantics at all internally. Rather ioremap or
537  * friends, and at least on 32-bit they add global TLB flushes and points
538  * of failure.
539  */
540
541 static void ttm_kmap_iter_linear_io_map_local(struct ttm_kmap_iter *iter,
542                                               struct iosys_map *dmap,
543                                               pgoff_t i)
544 {
545         struct ttm_kmap_iter_linear_io *iter_io =
546                 container_of(iter, typeof(*iter_io), base);
547
548         *dmap = iter_io->dmap;
549         iosys_map_incr(dmap, i * PAGE_SIZE);
550 }
551
552 static const struct ttm_kmap_iter_ops ttm_kmap_iter_linear_io_ops = {
553         .map_local =  ttm_kmap_iter_linear_io_map_local,
554         .maps_tt = false,
555 };
556
557 /**
558  * ttm_kmap_iter_linear_io_init - Initialize an iterator for linear io memory
559  * @iter_io: The iterator to initialize
560  * @bdev: The TTM device
561  * @mem: The ttm resource representing the iomap.
562  *
563  * This function is for internal TTM use only. It sets up a memcpy kmap iterator
564  * pointing at a linear chunk of io memory.
565  *
566  * Return: A pointer to the embedded struct ttm_kmap_iter or error pointer on
567  * failure.
568  */
569 struct ttm_kmap_iter *
570 ttm_kmap_iter_linear_io_init(struct ttm_kmap_iter_linear_io *iter_io,
571                              struct ttm_device *bdev,
572                              struct ttm_resource *mem)
573 {
574         int ret;
575
576         ret = ttm_mem_io_reserve(bdev, mem);
577         if (ret)
578                 goto out_err;
579         if (!mem->bus.is_iomem) {
580                 ret = -EINVAL;
581                 goto out_io_free;
582         }
583
584         if (mem->bus.addr) {
585                 iosys_map_set_vaddr(&iter_io->dmap, mem->bus.addr);
586                 iter_io->needs_unmap = false;
587         } else {
588                 size_t bus_size = (size_t)mem->num_pages << PAGE_SHIFT;
589
590                 iter_io->needs_unmap = true;
591                 memset(&iter_io->dmap, 0, sizeof(iter_io->dmap));
592                 if (mem->bus.caching == ttm_write_combined)
593                         iosys_map_set_vaddr_iomem(&iter_io->dmap,
594                                                   ioremap_wc(mem->bus.offset,
595                                                              bus_size));
596                 else if (mem->bus.caching == ttm_cached)
597                         iosys_map_set_vaddr(&iter_io->dmap,
598                                             memremap(mem->bus.offset, bus_size,
599                                                      MEMREMAP_WB |
600                                                      MEMREMAP_WT |
601                                                      MEMREMAP_WC));
602
603                 /* If uncached requested or if mapping cached or wc failed */
604                 if (iosys_map_is_null(&iter_io->dmap))
605                         iosys_map_set_vaddr_iomem(&iter_io->dmap,
606                                                   ioremap(mem->bus.offset,
607                                                           bus_size));
608
609                 if (iosys_map_is_null(&iter_io->dmap)) {
610                         ret = -ENOMEM;
611                         goto out_io_free;
612                 }
613         }
614
615         iter_io->base.ops = &ttm_kmap_iter_linear_io_ops;
616         return &iter_io->base;
617
618 out_io_free:
619         ttm_mem_io_free(bdev, mem);
620 out_err:
621         return ERR_PTR(ret);
622 }
623
624 /**
625  * ttm_kmap_iter_linear_io_fini - Clean up an iterator for linear io memory
626  * @iter_io: The iterator to initialize
627  * @bdev: The TTM device
628  * @mem: The ttm resource representing the iomap.
629  *
630  * This function is for internal TTM use only. It cleans up a memcpy kmap
631  * iterator initialized by ttm_kmap_iter_linear_io_init.
632  */
633 void
634 ttm_kmap_iter_linear_io_fini(struct ttm_kmap_iter_linear_io *iter_io,
635                              struct ttm_device *bdev,
636                              struct ttm_resource *mem)
637 {
638         if (iter_io->needs_unmap && iosys_map_is_set(&iter_io->dmap)) {
639                 if (iter_io->dmap.is_iomem)
640                         iounmap(iter_io->dmap.vaddr_iomem);
641                 else
642                         memunmap(iter_io->dmap.vaddr);
643         }
644
645         ttm_mem_io_free(bdev, mem);
646 }
647
648 #if defined(CONFIG_DEBUG_FS)
649
650 static int ttm_resource_manager_show(struct seq_file *m, void *unused)
651 {
652         struct ttm_resource_manager *man =
653                 (struct ttm_resource_manager *)m->private;
654         struct drm_printer p = drm_seq_file_printer(m);
655         ttm_resource_manager_debug(man, &p);
656         return 0;
657 }
658 DEFINE_SHOW_ATTRIBUTE(ttm_resource_manager);
659
660 #endif
661
662 /**
663  * ttm_resource_manager_create_debugfs - Create debugfs entry for specified
664  * resource manager.
665  * @man: The TTM resource manager for which the debugfs stats file be creates
666  * @parent: debugfs directory in which the file will reside
667  * @name: The filename to create.
668  *
669  * This function setups up a debugfs file that can be used to look
670  * at debug statistics of the specified ttm_resource_manager.
671  */
672 void ttm_resource_manager_create_debugfs(struct ttm_resource_manager *man,
673                                          struct dentry * parent,
674                                          const char *name)
675 {
676 #if defined(CONFIG_DEBUG_FS)
677         debugfs_create_file(name, 0444, parent, man, &ttm_resource_manager_fops);
678 #endif
679 }
680 EXPORT_SYMBOL(ttm_resource_manager_create_debugfs);