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