1 #ifndef __DRM_GEM_H__
2 #define __DRM_GEM_H__
3
4 /*
5 * GEM Graphics Execution Manager Driver Interfaces
6 *
7 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
8 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
9 * Copyright (c) 2009-2010, Code Aurora Forum.
10 * All rights reserved.
11 * Copyright © 2014 Intel Corporation
12 * Daniel Vetter <daniel.vetter@ffwll.ch>
13 *
14 * Author: Rickard E. (Rik) Faith <faith@valinux.com>
15 * Author: Gareth Hughes <gareth@valinux.com>
16 *
17 * Permission is hereby granted, free of charge, to any person obtaining a
18 * copy of this software and associated documentation files (the "Software"),
19 * to deal in the Software without restriction, including without limitation
20 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
21 * and/or sell copies of the Software, and to permit persons to whom the
22 * Software is furnished to do so, subject to the following conditions:
23 *
24 * The above copyright notice and this permission notice (including the next
25 * paragraph) shall be included in all copies or substantial portions of the
26 * Software.
27 *
28 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
29 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
30 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
31 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
32 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
33 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
34 * OTHER DEALINGS IN THE SOFTWARE.
35 */
36
37 #include <linux/kref.h>
38 #include <linux/dma-resv.h>
39 #include <linux/list.h>
40 #include <linux/mutex.h>
41
42 #include <drm/drm_vma_manager.h>
43
44 struct iosys_map;
45 struct drm_gem_object;
46
47 /**
48 * enum drm_gem_object_status - bitmask of object state for fdinfo reporting
49 * @DRM_GEM_OBJECT_RESIDENT: object is resident in memory (ie. not unpinned)
50 * @DRM_GEM_OBJECT_PURGEABLE: object marked as purgeable by userspace
51 *
52 * Bitmask of status used for fdinfo memory stats, see &drm_gem_object_funcs.status
53 * and drm_show_fdinfo(). Note that an object can DRM_GEM_OBJECT_PURGEABLE if
54 * it still active or not resident, in which case drm_show_fdinfo() will not
55 * account for it as purgeable. So drivers do not need to check if the buffer
56 * is idle and resident to return this bit. (Ie. userspace can mark a buffer
57 * as purgeable even while it is still busy on the GPU.. it does not _actually_
58 * become puregeable until it becomes idle. The status gem object func does
59 * not need to consider this.)
60 */
61 enum drm_gem_object_status {
62 DRM_GEM_OBJECT_RESIDENT = BIT(0),
63 DRM_GEM_OBJECT_PURGEABLE = BIT(1),
64 };
65
66 /**
67 * struct drm_gem_object_funcs - GEM object functions
68 */
69 struct drm_gem_object_funcs {
70 /**
71 * @free:
72 *
73 * Deconstructor for drm_gem_objects.
74 *
75 * This callback is mandatory.
76 */
77 void (*free)(struct drm_gem_object *obj);
78
79 /**
80 * @open:
81 *
82 * Called upon GEM handle creation.
83 *
84 * This callback is optional.
85 */
86 int (*open)(struct drm_gem_object *obj, struct drm_file *file);
87
88 /**
89 * @close:
90 *
91 * Called upon GEM handle release.
92 *
93 * This callback is optional.
94 */
95 void (*close)(struct drm_gem_object *obj, struct drm_file *file);
96
97 /**
98 * @print_info:
99 *
100 * If driver subclasses struct &drm_gem_object, it can implement this
101 * optional hook for printing additional driver specific info.
102 *
103 * drm_printf_indent() should be used in the callback passing it the
104 * indent argument.
105 *
106 * This callback is called from drm_gem_print_info().
107 *
108 * This callback is optional.
109 */
110 void (*print_info)(struct drm_printer *p, unsigned int indent,
111 const struct drm_gem_object *obj);
112
113 /**
114 * @export:
115 *
116 * Export backing buffer as a &dma_buf.
117 * If this is not set drm_gem_prime_export() is used.
118 *
119 * This callback is optional.
120 */
121 struct dma_buf *(*export)(struct drm_gem_object *obj, int flags);
122
123 /**
124 * @pin:
125 *
126 * Pin backing buffer in memory. Used by the drm_gem_map_attach() helper.
127 *
128 * This callback is optional.
129 */
130 int (*pin)(struct drm_gem_object *obj);
131
132 /**
133 * @unpin:
134 *
135 * Unpin backing buffer. Used by the drm_gem_map_detach() helper.
136 *
137 * This callback is optional.
138 */
139 void (*unpin)(struct drm_gem_object *obj);
140
141 /**
142 * @get_sg_table:
143 *
144 * Returns a Scatter-Gather table representation of the buffer.
145 * Used when exporting a buffer by the drm_gem_map_dma_buf() helper.
146 * Releasing is done by calling dma_unmap_sg_attrs() and sg_free_table()
147 * in drm_gem_unmap_buf(), therefore these helpers and this callback
148 * here cannot be used for sg tables pointing at driver private memory
149 * ranges.
150 *
151 * See also drm_prime_pages_to_sg().
152 */
153 struct sg_table *(*get_sg_table)(struct drm_gem_object *obj);
154
155 /**
156 * @vmap:
157 *
158 * Returns a virtual address for the buffer. Used by the
159 * drm_gem_dmabuf_vmap() helper.
160 *
161 * This callback is optional.
162 */
163 int (*vmap)(struct drm_gem_object *obj, struct iosys_map *map);
164
165 /**
166 * @vunmap:
167 *
168 * Releases the address previously returned by @vmap. Used by the
169 * drm_gem_dmabuf_vunmap() helper.
170 *
171 * This callback is optional.
172 */
173 void (*vunmap)(struct drm_gem_object *obj, struct iosys_map *map);
174
175 /**
176 * @mmap:
177 *
178 * Handle mmap() of the gem object, setup vma accordingly.
179 *
180 * This callback is optional.
181 *
182 * The callback is used by both drm_gem_mmap_obj() and
183 * drm_gem_prime_mmap(). When @mmap is present @vm_ops is not
184 * used, the @mmap callback must set vma->vm_ops instead.
185 */
186 int (*mmap)(struct drm_gem_object *obj, struct vm_area_struct *vma);
187
188 /**
189 * @evict:
190 *
191 * Evicts gem object out from memory. Used by the drm_gem_object_evict()
192 * helper. Returns 0 on success, -errno otherwise.
193 *
194 * This callback is optional.
195 */
196 int (*evict)(struct drm_gem_object *obj);
197
198 /**
199 * @status:
200 *
201 * The optional status callback can return additional object state
202 * which determines which stats the object is counted against. The
203 * callback is called under table_lock. Racing against object status
204 * change is "harmless", and the callback can expect to not race
205 * against object destruction.
206 *
207 * Called by drm_show_memory_stats().
208 */
209 enum drm_gem_object_status (*status)(struct drm_gem_object *obj);
210
211 /**
212 * @vm_ops:
213 *
214 * Virtual memory operations used with mmap.
215 *
216 * This is optional but necessary for mmap support.
217 */
218 const struct vm_operations_struct *vm_ops;
219 };
220
221 /**
222 * struct drm_gem_lru - A simple LRU helper
223 *
224 * A helper for tracking GEM objects in a given state, to aid in
225 * driver's shrinker implementation. Tracks the count of pages
226 * for lockless &shrinker.count_objects, and provides
227 * &drm_gem_lru_scan for driver's &shrinker.scan_objects
228 * implementation.
229 */
230 struct drm_gem_lru {
231 /**
232 * @lock:
233 *
234 * Lock protecting movement of GEM objects between LRUs. All
235 * LRUs that the object can move between should be protected
236 * by the same lock.
237 */
238 struct mutex *lock;
239
240 /**
241 * @count:
242 *
243 * The total number of backing pages of the GEM objects in
244 * this LRU.
245 */
246 long count;
247
248 /**
249 * @list:
250 *
251 * The LRU list.
252 */
253 struct list_head list;
254 };
255
256 /**
257 * struct drm_gem_object - GEM buffer object
258 *
259 * This structure defines the generic parts for GEM buffer objects, which are
260 * mostly around handling mmap and userspace handles.
261 *
262 * Buffer objects are often abbreviated to BO.
263 */
264 struct drm_gem_object {
265 /**
266 * @refcount:
267 *
268 * Reference count of this object
269 *
270 * Please use drm_gem_object_get() to acquire and drm_gem_object_put_locked()
271 * or drm_gem_object_put() to release a reference to a GEM
272 * buffer object.
273 */
274 struct kref refcount;
275
276 /**
277 * @handle_count:
278 *
279 * This is the GEM file_priv handle count of this object.
280 *
281 * Each handle also holds a reference. Note that when the handle_count
282 * drops to 0 any global names (e.g. the id in the flink namespace) will
283 * be cleared.
284 *
285 * Protected by &drm_device.object_name_lock.
286 */
287 unsigned handle_count;
288
289 /**
290 * @dev: DRM dev this object belongs to.
291 */
292 struct drm_device *dev;
293
294 /**
295 * @filp:
296 *
297 * SHMEM file node used as backing storage for swappable buffer objects.
298 * GEM also supports driver private objects with driver-specific backing
299 * storage (contiguous DMA memory, special reserved blocks). In this
300 * case @filp is NULL.
301 */
302 struct file *filp;
303
304 /**
305 * @vma_node:
306 *
307 * Mapping info for this object to support mmap. Drivers are supposed to
308 * allocate the mmap offset using drm_gem_create_mmap_offset(). The
309 * offset itself can be retrieved using drm_vma_node_offset_addr().
310 *
311 * Memory mapping itself is handled by drm_gem_mmap(), which also checks
312 * that userspace is allowed to access the object.
313 */
314 struct drm_vma_offset_node vma_node;
315
316 /**
317 * @size:
318 *
319 * Size of the object, in bytes. Immutable over the object's
320 * lifetime.
321 */
322 size_t size;
323
324 /**
325 * @name:
326 *
327 * Global name for this object, starts at 1. 0 means unnamed.
328 * Access is covered by &drm_device.object_name_lock. This is used by
329 * the GEM_FLINK and GEM_OPEN ioctls.
330 */
331 int name;
332
333 /**
334 * @dma_buf:
335 *
336 * dma-buf associated with this GEM object.
337 *
338 * Pointer to the dma-buf associated with this gem object (either
339 * through importing or exporting). We break the resulting reference
340 * loop when the last gem handle for this object is released.
341 *
342 * Protected by &drm_device.object_name_lock.
343 */
344 struct dma_buf *dma_buf;
345
346 /**
347 * @import_attach:
348 *
349 * dma-buf attachment backing this object.
350 *
351 * Any foreign dma_buf imported as a gem object has this set to the
352 * attachment point for the device. This is invariant over the lifetime
353 * of a gem object.
354 *
355 * The &drm_gem_object_funcs.free callback is responsible for
356 * cleaning up the dma_buf attachment and references acquired at import
357 * time.
358 *
359 * Note that the drm gem/prime core does not depend upon drivers setting
360 * this field any more. So for drivers where this doesn't make sense
361 * (e.g. virtual devices or a displaylink behind an usb bus) they can
362 * simply leave it as NULL.
363 */
364 struct dma_buf_attachment *import_attach;
365
366 /**
367 * @resv:
368 *
369 * Pointer to reservation object associated with the this GEM object.
370 *
371 * Normally (@resv == &@_resv) except for imported GEM objects.
372 */
373 struct dma_resv *resv;
374
375 /**
376 * @_resv:
377 *
378 * A reservation object for this GEM object.
379 *
380 * This is unused for imported GEM objects.
381 */
382 struct dma_resv _resv;
383
384 /**
385 * @gpuva:
386 *
387 * Provides the list of GPU VAs attached to this GEM object.
388 *
389 * Drivers should lock list accesses with the GEMs &dma_resv lock
390 * (&drm_gem_object.resv) or a custom lock if one is provided.
391 */
392 struct {
393 struct list_head list;
394
395 #ifdef CONFIG_LOCKDEP
396 struct lockdep_map *lock_dep_map;
397 #endif
398 } gpuva;
399
400 /**
401 * @funcs:
402 *
403 * Optional GEM object functions. If this is set, it will be used instead of the
404 * corresponding &drm_driver GEM callbacks.
405 *
406 * New drivers should use this.
407 *
408 */
409 const struct drm_gem_object_funcs *funcs;
410
411 /**
412 * @lru_node:
413 *
414 * List node in a &drm_gem_lru.
415 */
416 struct list_head lru_node;
417
418 /**
419 * @lru:
420 *
421 * The current LRU list that the GEM object is on.
422 */
423 struct drm_gem_lru *lru;
424 };
425
426 /**
427 * DRM_GEM_FOPS - Default drm GEM file operations
428 *
429 * This macro provides a shorthand for setting the GEM file ops in the
430 * &file_operations structure. If all you need are the default ops, use
431 * DEFINE_DRM_GEM_FOPS instead.
432 */
433 #define DRM_GEM_FOPS \
434 .open = drm_open,\
435 .release = drm_release,\
436 .unlocked_ioctl = drm_ioctl,\
437 .compat_ioctl = drm_compat_ioctl,\
438 .poll = drm_poll,\
439 .read = drm_read,\
440 .llseek = noop_llseek,\
441 .mmap = drm_gem_mmap
442
443 /**
444 * DEFINE_DRM_GEM_FOPS() - macro to generate file operations for GEM drivers
445 * @name: name for the generated structure
446 *
447 * This macro autogenerates a suitable &struct file_operations for GEM based
448 * drivers, which can be assigned to &drm_driver.fops. Note that this structure
449 * cannot be shared between drivers, because it contains a reference to the
450 * current module using THIS_MODULE.
451 *
452 * Note that the declaration is already marked as static - if you need a
453 * non-static version of this you're probably doing it wrong and will break the
454 * THIS_MODULE reference by accident.
455 */
456 #define DEFINE_DRM_GEM_FOPS(name) \
457 static const struct file_operations name = {\
458 .owner = THIS_MODULE,\
459 DRM_GEM_FOPS,\
460 }
461
462 void drm_gem_object_release(struct drm_gem_object *obj);
463 void drm_gem_object_free(struct kref *kref);
464 int drm_gem_object_init(struct drm_device *dev,
465 struct drm_gem_object *obj, size_t size);
466 void drm_gem_private_object_init(struct drm_device *dev,
467 struct drm_gem_object *obj, size_t size);
468 void drm_gem_private_object_fini(struct drm_gem_object *obj);
469 void drm_gem_vm_open(struct vm_area_struct *vma);
470 void drm_gem_vm_close(struct vm_area_struct *vma);
471 int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size,
472 struct vm_area_struct *vma);
473 int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma);
474
475 /**
476 * drm_gem_object_get - acquire a GEM buffer object reference
477 * @obj: GEM buffer object
478 *
479 * This function acquires an additional reference to @obj. It is illegal to
480 * call this without already holding a reference. No locks required.
481 */
drm_gem_object_get(struct drm_gem_object * obj)482 static inline void drm_gem_object_get(struct drm_gem_object *obj)
483 {
484 kref_get(&obj->refcount);
485 }
486
487 __attribute__((nonnull))
488 static inline void
__drm_gem_object_put(struct drm_gem_object * obj)489 __drm_gem_object_put(struct drm_gem_object *obj)
490 {
491 kref_put(&obj->refcount, drm_gem_object_free);
492 }
493
494 /**
495 * drm_gem_object_put - drop a GEM buffer object reference
496 * @obj: GEM buffer object
497 *
498 * This releases a reference to @obj.
499 */
500 static inline void
drm_gem_object_put(struct drm_gem_object * obj)501 drm_gem_object_put(struct drm_gem_object *obj)
502 {
503 if (obj)
504 __drm_gem_object_put(obj);
505 }
506
507 int drm_gem_handle_create(struct drm_file *file_priv,
508 struct drm_gem_object *obj,
509 u32 *handlep);
510 int drm_gem_handle_delete(struct drm_file *filp, u32 handle);
511
512
513 void drm_gem_free_mmap_offset(struct drm_gem_object *obj);
514 int drm_gem_create_mmap_offset(struct drm_gem_object *obj);
515 int drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size);
516
517 struct page **drm_gem_get_pages(struct drm_gem_object *obj);
518 void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
519 bool dirty, bool accessed);
520
521 int drm_gem_vmap_unlocked(struct drm_gem_object *obj, struct iosys_map *map);
522 void drm_gem_vunmap_unlocked(struct drm_gem_object *obj, struct iosys_map *map);
523
524 int drm_gem_objects_lookup(struct drm_file *filp, void __user *bo_handles,
525 int count, struct drm_gem_object ***objs_out);
526 struct drm_gem_object *drm_gem_object_lookup(struct drm_file *filp, u32 handle);
527 long drm_gem_dma_resv_wait(struct drm_file *filep, u32 handle,
528 bool wait_all, unsigned long timeout);
529 int drm_gem_lock_reservations(struct drm_gem_object **objs, int count,
530 struct ww_acquire_ctx *acquire_ctx);
531 void drm_gem_unlock_reservations(struct drm_gem_object **objs, int count,
532 struct ww_acquire_ctx *acquire_ctx);
533 int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
534 u32 handle, u64 *offset);
535
536 void drm_gem_lru_init(struct drm_gem_lru *lru, struct mutex *lock);
537 void drm_gem_lru_remove(struct drm_gem_object *obj);
538 void drm_gem_lru_move_tail_locked(struct drm_gem_lru *lru, struct drm_gem_object *obj);
539 void drm_gem_lru_move_tail(struct drm_gem_lru *lru, struct drm_gem_object *obj);
540 unsigned long drm_gem_lru_scan(struct drm_gem_lru *lru,
541 unsigned int nr_to_scan,
542 unsigned long *remaining,
543 bool (*shrink)(struct drm_gem_object *obj));
544
545 int drm_gem_evict(struct drm_gem_object *obj);
546
547 /**
548 * drm_gem_object_is_shared_for_memory_stats - helper for shared memory stats
549 *
550 * This helper should only be used for fdinfo shared memory stats to determine
551 * if a GEM object is shared.
552 *
553 * @obj: obj in question
554 */
drm_gem_object_is_shared_for_memory_stats(struct drm_gem_object * obj)555 static inline bool drm_gem_object_is_shared_for_memory_stats(struct drm_gem_object *obj)
556 {
557 return (obj->handle_count > 1) || obj->dma_buf;
558 }
559
560 #ifdef CONFIG_LOCKDEP
561 /**
562 * drm_gem_gpuva_set_lock() - Set the lock protecting accesses to the gpuva list.
563 * @obj: the &drm_gem_object
564 * @lock: the lock used to protect the gpuva list. The locking primitive
565 * must contain a dep_map field.
566 *
567 * Call this if you're not proctecting access to the gpuva list with the
568 * dma-resv lock, but with a custom lock.
569 */
570 #define drm_gem_gpuva_set_lock(obj, lock) \
571 if (!WARN((obj)->gpuva.lock_dep_map, \
572 "GEM GPUVA lock should be set only once.")) \
573 (obj)->gpuva.lock_dep_map = &(lock)->dep_map
574 #define drm_gem_gpuva_assert_lock_held(obj) \
575 lockdep_assert((obj)->gpuva.lock_dep_map ? \
576 lock_is_held((obj)->gpuva.lock_dep_map) : \
577 dma_resv_held((obj)->resv))
578 #else
579 #define drm_gem_gpuva_set_lock(obj, lock) do {} while (0)
580 #define drm_gem_gpuva_assert_lock_held(obj) do {} while (0)
581 #endif
582
583 /**
584 * drm_gem_gpuva_init() - initialize the gpuva list of a GEM object
585 * @obj: the &drm_gem_object
586 *
587 * This initializes the &drm_gem_object's &drm_gpuva list.
588 *
589 * Calling this function is only necessary for drivers intending to support the
590 * &drm_driver_feature DRIVER_GEM_GPUVA.
591 *
592 * See also drm_gem_gpuva_set_lock().
593 */
drm_gem_gpuva_init(struct drm_gem_object * obj)594 static inline void drm_gem_gpuva_init(struct drm_gem_object *obj)
595 {
596 INIT_LIST_HEAD(&obj->gpuva.list);
597 }
598
599 /**
600 * drm_gem_for_each_gpuva() - iternator to walk over a list of gpuvas
601 * @entry__: &drm_gpuva structure to assign to in each iteration step
602 * @obj__: the &drm_gem_object the &drm_gpuvas to walk are associated with
603 *
604 * This iterator walks over all &drm_gpuva structures associated with the
605 * &drm_gpuva_manager.
606 */
607 #define drm_gem_for_each_gpuva(entry__, obj__) \
608 list_for_each_entry(entry__, &(obj__)->gpuva.list, gem.entry)
609
610 /**
611 * drm_gem_for_each_gpuva_safe() - iternator to safely walk over a list of
612 * gpuvas
613 * @entry__: &drm_gpuva structure to assign to in each iteration step
614 * @next__: &next &drm_gpuva to store the next step
615 * @obj__: the &drm_gem_object the &drm_gpuvas to walk are associated with
616 *
617 * This iterator walks over all &drm_gpuva structures associated with the
618 * &drm_gem_object. It is implemented with list_for_each_entry_safe(), hence
619 * it is save against removal of elements.
620 */
621 #define drm_gem_for_each_gpuva_safe(entry__, next__, obj__) \
622 list_for_each_entry_safe(entry__, next__, &(obj__)->gpuva.list, gem.entry)
623
624 #endif /* __DRM_GEM_H__ */
625