xref: /linux/include/drm/drm_gem.h (revision 85502b2214d50ba0ddf2a5fb454e4d28a160d175)
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-buf.h>
39 #include <linux/dma-resv.h>
40 #include <linux/list.h>
41 #include <linux/mutex.h>
42 
43 #include <drm/drm_vma_manager.h>
44 
45 struct iosys_map;
46 struct drm_gem_object;
47 
48 /**
49  * enum drm_gem_object_status - bitmask of object state for fdinfo reporting
50  * @DRM_GEM_OBJECT_RESIDENT: object is resident in memory (ie. not unpinned)
51  * @DRM_GEM_OBJECT_PURGEABLE: object marked as purgeable by userspace
52  * @DRM_GEM_OBJECT_ACTIVE: object is currently used by an active submission
53  *
54  * Bitmask of status used for fdinfo memory stats, see &drm_gem_object_funcs.status
55  * and drm_show_fdinfo().  Note that an object can report DRM_GEM_OBJECT_PURGEABLE
56  * and be active or not resident, in which case drm_show_fdinfo() will not
57  * account for it as purgeable.  So drivers do not need to check if the buffer
58  * is idle and resident to return this bit, i.e. userspace can mark a buffer as
59  * purgeable even while it is still busy on the GPU. It will not get reported in
60  * the puregeable stats until it becomes idle.  The status gem object func does
61  * not need to consider this.
62  */
63 enum drm_gem_object_status {
64 	DRM_GEM_OBJECT_RESIDENT  = BIT(0),
65 	DRM_GEM_OBJECT_PURGEABLE = BIT(1),
66 	DRM_GEM_OBJECT_ACTIVE    = BIT(2),
67 };
68 
69 /**
70  * struct drm_gem_object_funcs - GEM object functions
71  */
72 struct drm_gem_object_funcs {
73 	/**
74 	 * @free:
75 	 *
76 	 * Deconstructor for drm_gem_objects.
77 	 *
78 	 * This callback is mandatory.
79 	 */
80 	void (*free)(struct drm_gem_object *obj);
81 
82 	/**
83 	 * @open:
84 	 *
85 	 * Called upon GEM handle creation.
86 	 *
87 	 * This callback is optional.
88 	 */
89 	int (*open)(struct drm_gem_object *obj, struct drm_file *file);
90 
91 	/**
92 	 * @close:
93 	 *
94 	 * Called upon GEM handle release.
95 	 *
96 	 * This callback is optional.
97 	 */
98 	void (*close)(struct drm_gem_object *obj, struct drm_file *file);
99 
100 	/**
101 	 * @print_info:
102 	 *
103 	 * If driver subclasses struct &drm_gem_object, it can implement this
104 	 * optional hook for printing additional driver specific info.
105 	 *
106 	 * drm_printf_indent() should be used in the callback passing it the
107 	 * indent argument.
108 	 *
109 	 * This callback is called from drm_gem_print_info().
110 	 *
111 	 * This callback is optional.
112 	 */
113 	void (*print_info)(struct drm_printer *p, unsigned int indent,
114 			   const struct drm_gem_object *obj);
115 
116 	/**
117 	 * @export:
118 	 *
119 	 * Export backing buffer as a &dma_buf.
120 	 * If this is not set drm_gem_prime_export() is used.
121 	 *
122 	 * This callback is optional.
123 	 */
124 	struct dma_buf *(*export)(struct drm_gem_object *obj, int flags);
125 
126 	/**
127 	 * @pin:
128 	 *
129 	 * Pin backing buffer in memory. Used by the drm_gem_map_attach() helper.
130 	 *
131 	 * This callback is optional.
132 	 */
133 	int (*pin)(struct drm_gem_object *obj);
134 
135 	/**
136 	 * @unpin:
137 	 *
138 	 * Unpin backing buffer. Used by the drm_gem_map_detach() helper.
139 	 *
140 	 * This callback is optional.
141 	 */
142 	void (*unpin)(struct drm_gem_object *obj);
143 
144 	/**
145 	 * @get_sg_table:
146 	 *
147 	 * Returns a Scatter-Gather table representation of the buffer.
148 	 * Used when exporting a buffer by the drm_gem_map_dma_buf() helper.
149 	 * Releasing is done by calling dma_unmap_sg_attrs() and sg_free_table()
150 	 * in drm_gem_unmap_buf(), therefore these helpers and this callback
151 	 * here cannot be used for sg tables pointing at driver private memory
152 	 * ranges.
153 	 *
154 	 * See also drm_prime_pages_to_sg().
155 	 */
156 	struct sg_table *(*get_sg_table)(struct drm_gem_object *obj);
157 
158 	/**
159 	 * @vmap:
160 	 *
161 	 * Returns a virtual address for the buffer. Used by the
162 	 * drm_gem_dmabuf_vmap() helper. Called with a held GEM reservation
163 	 * lock.
164 	 *
165 	 * This callback is optional.
166 	 */
167 	int (*vmap)(struct drm_gem_object *obj, struct iosys_map *map);
168 
169 	/**
170 	 * @vunmap:
171 	 *
172 	 * Releases the address previously returned by @vmap. Used by the
173 	 * drm_gem_dmabuf_vunmap() helper. Called with a held GEM reservation
174 	 * lock.
175 	 *
176 	 * This callback is optional.
177 	 */
178 	void (*vunmap)(struct drm_gem_object *obj, struct iosys_map *map);
179 
180 	/**
181 	 * @mmap:
182 	 *
183 	 * Handle mmap() of the gem object, setup vma accordingly.
184 	 *
185 	 * This callback is optional.
186 	 *
187 	 * The callback is used by both drm_gem_mmap_obj() and
188 	 * drm_gem_prime_mmap().  When @mmap is present @vm_ops is not
189 	 * used, the @mmap callback must set vma->vm_ops instead.
190 	 */
191 	int (*mmap)(struct drm_gem_object *obj, struct vm_area_struct *vma);
192 
193 	/**
194 	 * @evict:
195 	 *
196 	 * Evicts gem object out from memory. Used by the drm_gem_object_evict()
197 	 * helper. Returns 0 on success, -errno otherwise. Called with a held
198 	 * GEM reservation lock.
199 	 *
200 	 * This callback is optional.
201 	 */
202 	int (*evict)(struct drm_gem_object *obj);
203 
204 	/**
205 	 * @status:
206 	 *
207 	 * The optional status callback can return additional object state
208 	 * which determines which stats the object is counted against.  The
209 	 * callback is called under table_lock.  Racing against object status
210 	 * change is "harmless", and the callback can expect to not race
211 	 * against object destruction.
212 	 *
213 	 * Called by drm_show_memory_stats().
214 	 */
215 	enum drm_gem_object_status (*status)(struct drm_gem_object *obj);
216 
217 	/**
218 	 * @rss:
219 	 *
220 	 * Return resident size of the object in physical memory.
221 	 *
222 	 * Called by drm_show_memory_stats().
223 	 */
224 	size_t (*rss)(struct drm_gem_object *obj);
225 
226 	/**
227 	 * @vm_ops:
228 	 *
229 	 * Virtual memory operations used with mmap.
230 	 *
231 	 * This is optional but necessary for mmap support.
232 	 */
233 	const struct vm_operations_struct *vm_ops;
234 };
235 
236 /**
237  * struct drm_gem_lru - A simple LRU helper
238  *
239  * A helper for tracking GEM objects in a given state, to aid in
240  * driver's shrinker implementation.  Tracks the count of pages
241  * for lockless &shrinker.count_objects, and provides
242  * &drm_gem_lru_scan for driver's &shrinker.scan_objects
243  * implementation.
244  */
245 struct drm_gem_lru {
246 	/**
247 	 * @lock:
248 	 *
249 	 * Lock protecting movement of GEM objects between LRUs.  All
250 	 * LRUs that the object can move between should be protected
251 	 * by the same lock.
252 	 */
253 	struct mutex *lock;
254 
255 	/**
256 	 * @count:
257 	 *
258 	 * The total number of backing pages of the GEM objects in
259 	 * this LRU.
260 	 */
261 	long count;
262 
263 	/**
264 	 * @list:
265 	 *
266 	 * The LRU list.
267 	 */
268 	struct list_head list;
269 };
270 
271 /**
272  * struct drm_gem_object - GEM buffer object
273  *
274  * This structure defines the generic parts for GEM buffer objects, which are
275  * mostly around handling mmap and userspace handles.
276  *
277  * Buffer objects are often abbreviated to BO.
278  */
279 struct drm_gem_object {
280 	/**
281 	 * @refcount:
282 	 *
283 	 * Reference count of this object
284 	 *
285 	 * Please use drm_gem_object_get() to acquire and drm_gem_object_put_locked()
286 	 * or drm_gem_object_put() to release a reference to a GEM
287 	 * buffer object.
288 	 */
289 	struct kref refcount;
290 
291 	/**
292 	 * @handle_count:
293 	 *
294 	 * This is the GEM file_priv handle count of this object.
295 	 *
296 	 * Each handle also holds a reference. Note that when the handle_count
297 	 * drops to 0 any global names (e.g. the id in the flink namespace) will
298 	 * be cleared.
299 	 *
300 	 * Protected by &drm_device.object_name_lock.
301 	 */
302 	unsigned handle_count;
303 
304 	/**
305 	 * @dev: DRM dev this object belongs to.
306 	 */
307 	struct drm_device *dev;
308 
309 	/**
310 	 * @filp:
311 	 *
312 	 * SHMEM file node used as backing storage for swappable buffer objects.
313 	 * GEM also supports driver private objects with driver-specific backing
314 	 * storage (contiguous DMA memory, special reserved blocks). In this
315 	 * case @filp is NULL.
316 	 */
317 	struct file *filp;
318 
319 	/**
320 	 * @vma_node:
321 	 *
322 	 * Mapping info for this object to support mmap. Drivers are supposed to
323 	 * allocate the mmap offset using drm_gem_create_mmap_offset(). The
324 	 * offset itself can be retrieved using drm_vma_node_offset_addr().
325 	 *
326 	 * Memory mapping itself is handled by drm_gem_mmap(), which also checks
327 	 * that userspace is allowed to access the object.
328 	 */
329 	struct drm_vma_offset_node vma_node;
330 
331 	/**
332 	 * @size:
333 	 *
334 	 * Size of the object, in bytes.  Immutable over the object's
335 	 * lifetime.
336 	 */
337 	size_t size;
338 
339 	/**
340 	 * @name:
341 	 *
342 	 * Global name for this object, starts at 1. 0 means unnamed.
343 	 * Access is covered by &drm_device.object_name_lock. This is used by
344 	 * the GEM_FLINK and GEM_OPEN ioctls.
345 	 */
346 	int name;
347 
348 	/**
349 	 * @dma_buf:
350 	 *
351 	 * dma-buf associated with this GEM object.
352 	 *
353 	 * Pointer to the dma-buf associated with this gem object (either
354 	 * through importing or exporting). We break the resulting reference
355 	 * loop when the last gem handle for this object is released.
356 	 *
357 	 * Protected by &drm_device.object_name_lock.
358 	 */
359 	struct dma_buf *dma_buf;
360 
361 	/**
362 	 * @import_attach:
363 	 *
364 	 * dma-buf attachment backing this object.
365 	 *
366 	 * Any foreign dma_buf imported as a gem object has this set to the
367 	 * attachment point for the device. This is invariant over the lifetime
368 	 * of a gem object.
369 	 *
370 	 * The &drm_gem_object_funcs.free callback is responsible for
371 	 * cleaning up the dma_buf attachment and references acquired at import
372 	 * time.
373 	 *
374 	 * Note that the drm gem/prime core does not depend upon drivers setting
375 	 * this field any more. So for drivers where this doesn't make sense
376 	 * (e.g. virtual devices or a displaylink behind an usb bus) they can
377 	 * simply leave it as NULL.
378 	 */
379 	struct dma_buf_attachment *import_attach;
380 
381 	/**
382 	 * @resv:
383 	 *
384 	 * Pointer to reservation object associated with the this GEM object.
385 	 *
386 	 * Normally (@resv == &@_resv) except for imported GEM objects.
387 	 */
388 	struct dma_resv *resv;
389 
390 	/**
391 	 * @_resv:
392 	 *
393 	 * A reservation object for this GEM object.
394 	 *
395 	 * This is unused for imported GEM objects.
396 	 */
397 	struct dma_resv _resv;
398 
399 	/**
400 	 * @gpuva:
401 	 *
402 	 * Provides the list of GPU VAs attached to this GEM object.
403 	 *
404 	 * Drivers should lock list accesses with the GEMs &dma_resv lock
405 	 * (&drm_gem_object.resv) or a custom lock if one is provided.
406 	 */
407 	struct {
408 		struct list_head list;
409 
410 #ifdef CONFIG_LOCKDEP
411 		struct lockdep_map *lock_dep_map;
412 #endif
413 	} gpuva;
414 
415 	/**
416 	 * @funcs:
417 	 *
418 	 * Optional GEM object functions. If this is set, it will be used instead of the
419 	 * corresponding &drm_driver GEM callbacks.
420 	 *
421 	 * New drivers should use this.
422 	 *
423 	 */
424 	const struct drm_gem_object_funcs *funcs;
425 
426 	/**
427 	 * @lru_node:
428 	 *
429 	 * List node in a &drm_gem_lru.
430 	 */
431 	struct list_head lru_node;
432 
433 	/**
434 	 * @lru:
435 	 *
436 	 * The current LRU list that the GEM object is on.
437 	 */
438 	struct drm_gem_lru *lru;
439 };
440 
441 /**
442  * DRM_GEM_FOPS - Default drm GEM file operations
443  *
444  * This macro provides a shorthand for setting the GEM file ops in the
445  * &file_operations structure.  If all you need are the default ops, use
446  * DEFINE_DRM_GEM_FOPS instead.
447  */
448 #define DRM_GEM_FOPS \
449 	.open		= drm_open,\
450 	.release	= drm_release,\
451 	.unlocked_ioctl	= drm_ioctl,\
452 	.compat_ioctl	= drm_compat_ioctl,\
453 	.poll		= drm_poll,\
454 	.read		= drm_read,\
455 	.llseek		= noop_llseek,\
456 	.mmap		= drm_gem_mmap, \
457 	.fop_flags	= FOP_UNSIGNED_OFFSET
458 
459 /**
460  * DEFINE_DRM_GEM_FOPS() - macro to generate file operations for GEM drivers
461  * @name: name for the generated structure
462  *
463  * This macro autogenerates a suitable &struct file_operations for GEM based
464  * drivers, which can be assigned to &drm_driver.fops. Note that this structure
465  * cannot be shared between drivers, because it contains a reference to the
466  * current module using THIS_MODULE.
467  *
468  * Note that the declaration is already marked as static - if you need a
469  * non-static version of this you're probably doing it wrong and will break the
470  * THIS_MODULE reference by accident.
471  */
472 #define DEFINE_DRM_GEM_FOPS(name) \
473 	static const struct file_operations name = {\
474 		.owner		= THIS_MODULE,\
475 		DRM_GEM_FOPS,\
476 	}
477 
478 void drm_gem_object_release(struct drm_gem_object *obj);
479 void drm_gem_object_free(struct kref *kref);
480 int drm_gem_object_init(struct drm_device *dev,
481 			struct drm_gem_object *obj, size_t size);
482 int drm_gem_object_init_with_mnt(struct drm_device *dev,
483 				 struct drm_gem_object *obj, size_t size,
484 				 struct vfsmount *gemfs);
485 void drm_gem_private_object_init(struct drm_device *dev,
486 				 struct drm_gem_object *obj, size_t size);
487 void drm_gem_private_object_fini(struct drm_gem_object *obj);
488 void drm_gem_vm_open(struct vm_area_struct *vma);
489 void drm_gem_vm_close(struct vm_area_struct *vma);
490 int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size,
491 		     struct vm_area_struct *vma);
492 int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma);
493 
494 /**
495  * drm_gem_object_get - acquire a GEM buffer object reference
496  * @obj: GEM buffer object
497  *
498  * This function acquires an additional reference to @obj. It is illegal to
499  * call this without already holding a reference. No locks required.
500  */
drm_gem_object_get(struct drm_gem_object * obj)501 static inline void drm_gem_object_get(struct drm_gem_object *obj)
502 {
503 	kref_get(&obj->refcount);
504 }
505 
506 __attribute__((nonnull))
507 static inline void
__drm_gem_object_put(struct drm_gem_object * obj)508 __drm_gem_object_put(struct drm_gem_object *obj)
509 {
510 	kref_put(&obj->refcount, drm_gem_object_free);
511 }
512 
513 /**
514  * drm_gem_object_put - drop a GEM buffer object reference
515  * @obj: GEM buffer object
516  *
517  * This releases a reference to @obj.
518  */
519 static inline void
drm_gem_object_put(struct drm_gem_object * obj)520 drm_gem_object_put(struct drm_gem_object *obj)
521 {
522 	if (obj)
523 		__drm_gem_object_put(obj);
524 }
525 
526 int drm_gem_handle_create(struct drm_file *file_priv,
527 			  struct drm_gem_object *obj,
528 			  u32 *handlep);
529 int drm_gem_handle_delete(struct drm_file *filp, u32 handle);
530 
531 
532 void drm_gem_free_mmap_offset(struct drm_gem_object *obj);
533 int drm_gem_create_mmap_offset(struct drm_gem_object *obj);
534 int drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size);
535 
536 struct page **drm_gem_get_pages(struct drm_gem_object *obj);
537 void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
538 		bool dirty, bool accessed);
539 
540 void drm_gem_lock(struct drm_gem_object *obj);
541 void drm_gem_unlock(struct drm_gem_object *obj);
542 
543 int drm_gem_vmap(struct drm_gem_object *obj, struct iosys_map *map);
544 void drm_gem_vunmap(struct drm_gem_object *obj, struct iosys_map *map);
545 
546 int drm_gem_objects_lookup(struct drm_file *filp, void __user *bo_handles,
547 			   int count, struct drm_gem_object ***objs_out);
548 struct drm_gem_object *drm_gem_object_lookup(struct drm_file *filp, u32 handle);
549 long drm_gem_dma_resv_wait(struct drm_file *filep, u32 handle,
550 				    bool wait_all, unsigned long timeout);
551 int drm_gem_lock_reservations(struct drm_gem_object **objs, int count,
552 			      struct ww_acquire_ctx *acquire_ctx);
553 void drm_gem_unlock_reservations(struct drm_gem_object **objs, int count,
554 				 struct ww_acquire_ctx *acquire_ctx);
555 int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
556 			    u32 handle, u64 *offset);
557 
558 void drm_gem_lru_init(struct drm_gem_lru *lru, struct mutex *lock);
559 void drm_gem_lru_remove(struct drm_gem_object *obj);
560 void drm_gem_lru_move_tail_locked(struct drm_gem_lru *lru, struct drm_gem_object *obj);
561 void drm_gem_lru_move_tail(struct drm_gem_lru *lru, struct drm_gem_object *obj);
562 unsigned long drm_gem_lru_scan(struct drm_gem_lru *lru,
563 			       unsigned int nr_to_scan,
564 			       unsigned long *remaining,
565 			       bool (*shrink)(struct drm_gem_object *obj));
566 
567 int drm_gem_evict_locked(struct drm_gem_object *obj);
568 
569 /**
570  * drm_gem_object_is_shared_for_memory_stats - helper for shared memory stats
571  *
572  * This helper should only be used for fdinfo shared memory stats to determine
573  * if a GEM object is shared.
574  *
575  * @obj: obj in question
576  */
drm_gem_object_is_shared_for_memory_stats(struct drm_gem_object * obj)577 static inline bool drm_gem_object_is_shared_for_memory_stats(struct drm_gem_object *obj)
578 {
579 	return (obj->handle_count > 1) || obj->dma_buf;
580 }
581 
582 /**
583  * drm_gem_is_imported() - Tests if GEM object's buffer has been imported
584  * @obj: the GEM object
585  *
586  * Returns:
587  * True if the GEM object's buffer has been imported, false otherwise
588  */
drm_gem_is_imported(const struct drm_gem_object * obj)589 static inline bool drm_gem_is_imported(const struct drm_gem_object *obj)
590 {
591 	return !!obj->import_attach;
592 }
593 
594 #ifdef CONFIG_LOCKDEP
595 /**
596  * drm_gem_gpuva_set_lock() - Set the lock protecting accesses to the gpuva list.
597  * @obj: the &drm_gem_object
598  * @lock: the lock used to protect the gpuva list. The locking primitive
599  * must contain a dep_map field.
600  *
601  * Call this if you're not proctecting access to the gpuva list with the
602  * dma-resv lock, but with a custom lock.
603  */
604 #define drm_gem_gpuva_set_lock(obj, lock) \
605 	if (!WARN((obj)->gpuva.lock_dep_map, \
606 		  "GEM GPUVA lock should be set only once.")) \
607 		(obj)->gpuva.lock_dep_map = &(lock)->dep_map
608 #define drm_gem_gpuva_assert_lock_held(obj) \
609 	lockdep_assert((obj)->gpuva.lock_dep_map ? \
610 		       lock_is_held((obj)->gpuva.lock_dep_map) : \
611 		       dma_resv_held((obj)->resv))
612 #else
613 #define drm_gem_gpuva_set_lock(obj, lock) do {} while (0)
614 #define drm_gem_gpuva_assert_lock_held(obj) do {} while (0)
615 #endif
616 
617 /**
618  * drm_gem_gpuva_init() - initialize the gpuva list of a GEM object
619  * @obj: the &drm_gem_object
620  *
621  * This initializes the &drm_gem_object's &drm_gpuvm_bo list.
622  *
623  * Calling this function is only necessary for drivers intending to support the
624  * &drm_driver_feature DRIVER_GEM_GPUVA.
625  *
626  * See also drm_gem_gpuva_set_lock().
627  */
drm_gem_gpuva_init(struct drm_gem_object * obj)628 static inline void drm_gem_gpuva_init(struct drm_gem_object *obj)
629 {
630 	INIT_LIST_HEAD(&obj->gpuva.list);
631 }
632 
633 /**
634  * drm_gem_for_each_gpuvm_bo() - iterator to walk over a list of &drm_gpuvm_bo
635  * @entry__: &drm_gpuvm_bo structure to assign to in each iteration step
636  * @obj__: the &drm_gem_object the &drm_gpuvm_bo to walk are associated with
637  *
638  * This iterator walks over all &drm_gpuvm_bo structures associated with the
639  * &drm_gem_object.
640  */
641 #define drm_gem_for_each_gpuvm_bo(entry__, obj__) \
642 	list_for_each_entry(entry__, &(obj__)->gpuva.list, list.entry.gem)
643 
644 /**
645  * drm_gem_for_each_gpuvm_bo_safe() - iterator to safely walk over a list of
646  * &drm_gpuvm_bo
647  * @entry__: &drm_gpuvm_bostructure to assign to in each iteration step
648  * @next__: &next &drm_gpuvm_bo to store the next step
649  * @obj__: the &drm_gem_object the &drm_gpuvm_bo to walk are associated with
650  *
651  * This iterator walks over all &drm_gpuvm_bo structures associated with the
652  * &drm_gem_object. It is implemented with list_for_each_entry_safe(), hence
653  * it is save against removal of elements.
654  */
655 #define drm_gem_for_each_gpuvm_bo_safe(entry__, next__, obj__) \
656 	list_for_each_entry_safe(entry__, next__, &(obj__)->gpuva.list, list.entry.gem)
657 
658 #endif /* __DRM_GEM_H__ */
659