xref: /linux/include/drm/drm_gpuvm.h (revision 1b78070aaef63512688aebfbc82365ef9d6660f1)
1 /* SPDX-License-Identifier: GPL-2.0-only OR MIT */
2 
3 #ifndef __DRM_GPUVM_H__
4 #define __DRM_GPUVM_H__
5 
6 /*
7  * Copyright (c) 2022 Red Hat.
8  *
9  * Permission is hereby granted, free of charge, to any person obtaining a
10  * copy of this software and associated documentation files (the "Software"),
11  * to deal in the Software without restriction, including without limitation
12  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
13  * and/or sell copies of the Software, and to permit persons to whom the
14  * Software is furnished to do so, subject to the following conditions:
15  *
16  * The above copyright notice and this permission notice shall be included in
17  * all copies or substantial portions of the Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
22  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
23  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
24  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
25  * OTHER DEALINGS IN THE SOFTWARE.
26  */
27 
28 #include <linux/dma-resv.h>
29 #include <linux/list.h>
30 #include <linux/llist.h>
31 #include <linux/rbtree.h>
32 #include <linux/types.h>
33 
34 #include <drm/drm_device.h>
35 #include <drm/drm_gem.h>
36 #include <drm/drm_exec.h>
37 
38 struct drm_gpuvm;
39 struct drm_gpuvm_bo;
40 struct drm_gpuvm_ops;
41 
42 /**
43  * enum drm_gpuva_flags - flags for struct drm_gpuva
44  */
45 enum drm_gpuva_flags {
46 	/**
47 	 * @DRM_GPUVA_INVALIDATED:
48 	 *
49 	 * Flag indicating that the &drm_gpuva's backing GEM is invalidated.
50 	 */
51 	DRM_GPUVA_INVALIDATED = (1 << 0),
52 
53 	/**
54 	 * @DRM_GPUVA_SPARSE:
55 	 *
56 	 * Flag indicating that the &drm_gpuva is a sparse mapping.
57 	 */
58 	DRM_GPUVA_SPARSE = (1 << 1),
59 
60 	/**
61 	 * @DRM_GPUVA_USERBITS: user defined bits
62 	 */
63 	DRM_GPUVA_USERBITS = (1 << 2),
64 };
65 
66 /**
67  * struct drm_gpuva - structure to track a GPU VA mapping
68  *
69  * This structure represents a GPU VA mapping and is associated with a
70  * &drm_gpuvm.
71  *
72  * Typically, this structure is embedded in bigger driver structures.
73  */
74 struct drm_gpuva {
75 	/**
76 	 * @vm: the &drm_gpuvm this object is associated with
77 	 */
78 	struct drm_gpuvm *vm;
79 
80 	/**
81 	 * @vm_bo: the &drm_gpuvm_bo abstraction for the mapped
82 	 * &drm_gem_object
83 	 */
84 	struct drm_gpuvm_bo *vm_bo;
85 
86 	/**
87 	 * @flags: the &drm_gpuva_flags for this mapping
88 	 */
89 	enum drm_gpuva_flags flags;
90 
91 	/**
92 	 * @va: structure containing the address and range of the &drm_gpuva
93 	 */
94 	struct {
95 		/**
96 		 * @va.addr: the start address
97 		 */
98 		u64 addr;
99 
100 		/*
101 		 * @range: the range
102 		 */
103 		u64 range;
104 	} va;
105 
106 	/**
107 	 * @gem: structure containing the &drm_gem_object and its offset
108 	 */
109 	struct {
110 		/**
111 		 * @gem.offset: the offset within the &drm_gem_object
112 		 */
113 		u64 offset;
114 
115 		/**
116 		 * @gem.obj: the mapped &drm_gem_object
117 		 */
118 		struct drm_gem_object *obj;
119 
120 		/**
121 		 * @gem.entry: the &list_head to attach this object to a &drm_gpuvm_bo
122 		 */
123 		struct list_head entry;
124 	} gem;
125 
126 	/**
127 	 * @rb: structure containing data to store &drm_gpuvas in a rb-tree
128 	 */
129 	struct {
130 		/**
131 		 * @rb.node: the rb-tree node
132 		 */
133 		struct rb_node node;
134 
135 		/**
136 		 * @rb.entry: The &list_head to additionally connect &drm_gpuvas
137 		 * in the same order they appear in the interval tree. This is
138 		 * useful to keep iterating &drm_gpuvas from a start node found
139 		 * through the rb-tree while doing modifications on the rb-tree
140 		 * itself.
141 		 */
142 		struct list_head entry;
143 
144 		/**
145 		 * @rb.__subtree_last: needed by the interval tree, holding last-in-subtree
146 		 */
147 		u64 __subtree_last;
148 	} rb;
149 };
150 
151 int drm_gpuva_insert(struct drm_gpuvm *gpuvm, struct drm_gpuva *va);
152 void drm_gpuva_remove(struct drm_gpuva *va);
153 
154 void drm_gpuva_link(struct drm_gpuva *va, struct drm_gpuvm_bo *vm_bo);
155 void drm_gpuva_unlink(struct drm_gpuva *va);
156 void drm_gpuva_unlink_defer(struct drm_gpuva *va);
157 
158 struct drm_gpuva *drm_gpuva_find(struct drm_gpuvm *gpuvm,
159 				 u64 addr, u64 range);
160 struct drm_gpuva *drm_gpuva_find_first(struct drm_gpuvm *gpuvm,
161 				       u64 addr, u64 range);
162 
163 /**
164  * drm_gpuva_invalidate() - sets whether the backing GEM of this &drm_gpuva is
165  * invalidated
166  * @va: the &drm_gpuva to set the invalidate flag for
167  * @invalidate: indicates whether the &drm_gpuva is invalidated
168  */
169 static inline void drm_gpuva_invalidate(struct drm_gpuva *va, bool invalidate)
170 {
171 	if (invalidate)
172 		va->flags |= DRM_GPUVA_INVALIDATED;
173 	else
174 		va->flags &= ~DRM_GPUVA_INVALIDATED;
175 }
176 
177 /**
178  * drm_gpuva_invalidated() - indicates whether the backing BO of this &drm_gpuva
179  * is invalidated
180  * @va: the &drm_gpuva to check
181  *
182  * Returns: %true if the GPU VA is invalidated, %false otherwise
183  */
184 static inline bool drm_gpuva_invalidated(struct drm_gpuva *va)
185 {
186 	return va->flags & DRM_GPUVA_INVALIDATED;
187 }
188 
189 /**
190  * enum drm_gpuvm_flags - flags for struct drm_gpuvm
191  */
192 enum drm_gpuvm_flags {
193 	/**
194 	 * @DRM_GPUVM_RESV_PROTECTED: GPUVM is protected externally by the
195 	 * GPUVM's &dma_resv lock
196 	 */
197 	DRM_GPUVM_RESV_PROTECTED = BIT(0),
198 
199 	/**
200 	 * @DRM_GPUVM_IMMEDIATE_MODE: use the locking scheme for GEMs designed
201 	 * for modifying the GPUVM during the fence signalling path
202 	 *
203 	 * When set, gpuva.lock is used to protect gpuva.list in all GEM
204 	 * objects associated with this GPUVM. Otherwise, the GEMs dma-resv is
205 	 * used.
206 	 */
207 	DRM_GPUVM_IMMEDIATE_MODE = BIT(1),
208 
209 	/**
210 	 * @DRM_GPUVM_USERBITS: user defined bits
211 	 */
212 	DRM_GPUVM_USERBITS = BIT(2),
213 };
214 
215 /**
216  * struct drm_gpuvm - DRM GPU VA Manager
217  *
218  * The DRM GPU VA Manager keeps track of a GPU's virtual address space by using
219  * &maple_tree structures. Typically, this structure is embedded in bigger
220  * driver structures.
221  *
222  * Drivers can pass addresses and ranges in an arbitrary unit, e.g. bytes or
223  * pages.
224  *
225  * There should be one manager instance per GPU virtual address space.
226  */
227 struct drm_gpuvm {
228 	/**
229 	 * @name: the name of the DRM GPU VA space
230 	 */
231 	const char *name;
232 
233 	/**
234 	 * @flags: the &drm_gpuvm_flags of this GPUVM
235 	 */
236 	enum drm_gpuvm_flags flags;
237 
238 	/**
239 	 * @drm: the &drm_device this VM lives in
240 	 */
241 	struct drm_device *drm;
242 
243 	/**
244 	 * @mm_start: start of the VA space
245 	 */
246 	u64 mm_start;
247 
248 	/**
249 	 * @mm_range: length of the VA space
250 	 */
251 	u64 mm_range;
252 
253 	/**
254 	 * @rb: structures to track &drm_gpuva entries
255 	 */
256 	struct {
257 		/**
258 		 * @rb.tree: the rb-tree to track GPU VA mappings
259 		 */
260 		struct rb_root_cached tree;
261 
262 		/**
263 		 * @rb.list: the &list_head to track GPU VA mappings
264 		 */
265 		struct list_head list;
266 	} rb;
267 
268 	/**
269 	 * @kref: reference count of this object
270 	 */
271 	struct kref kref;
272 
273 	/**
274 	 * @kernel_alloc_node:
275 	 *
276 	 * &drm_gpuva representing the address space cutout reserved for
277 	 * the kernel
278 	 */
279 	struct drm_gpuva kernel_alloc_node;
280 
281 	/**
282 	 * @ops: &drm_gpuvm_ops providing the split/merge steps to drivers
283 	 */
284 	const struct drm_gpuvm_ops *ops;
285 
286 	/**
287 	 * @r_obj: Resv GEM object; representing the GPUVM's common &dma_resv.
288 	 */
289 	struct drm_gem_object *r_obj;
290 
291 	/**
292 	 * @extobj: structure holding the extobj list
293 	 */
294 	struct {
295 		/**
296 		 * @extobj.list: &list_head storing &drm_gpuvm_bos serving as
297 		 * external object
298 		 */
299 		struct list_head list;
300 
301 		/**
302 		 * @extobj.local_list: pointer to the local list temporarily
303 		 * storing entries from the external object list
304 		 */
305 		struct list_head *local_list;
306 
307 		/**
308 		 * @extobj.lock: spinlock to protect the extobj list
309 		 */
310 		spinlock_t lock;
311 	} extobj;
312 
313 	/**
314 	 * @evict: structure holding the evict list and evict list lock
315 	 */
316 	struct {
317 		/**
318 		 * @evict.list: &list_head storing &drm_gpuvm_bos currently
319 		 * being evicted
320 		 */
321 		struct list_head list;
322 
323 		/**
324 		 * @evict.local_list: pointer to the local list temporarily
325 		 * storing entries from the evicted object list
326 		 */
327 		struct list_head *local_list;
328 
329 		/**
330 		 * @evict.lock: spinlock to protect the evict list
331 		 */
332 		spinlock_t lock;
333 	} evict;
334 
335 	/**
336 	 * @bo_defer: structure holding vm_bos that need to be destroyed
337 	 */
338 	struct llist_head bo_defer;
339 };
340 
341 void drm_gpuvm_init(struct drm_gpuvm *gpuvm, const char *name,
342 		    enum drm_gpuvm_flags flags,
343 		    struct drm_device *drm,
344 		    struct drm_gem_object *r_obj,
345 		    u64 start_offset, u64 range,
346 		    u64 reserve_offset, u64 reserve_range,
347 		    const struct drm_gpuvm_ops *ops);
348 
349 /**
350  * drm_gpuvm_get() - acquire a struct drm_gpuvm reference
351  * @gpuvm: the &drm_gpuvm to acquire the reference of
352  *
353  * This function acquires an additional reference to @gpuvm. It is illegal to
354  * call this without already holding a reference. No locks required.
355  *
356  * Returns: the &struct drm_gpuvm pointer
357  */
358 static inline struct drm_gpuvm *
359 drm_gpuvm_get(struct drm_gpuvm *gpuvm)
360 {
361 	kref_get(&gpuvm->kref);
362 
363 	return gpuvm;
364 }
365 
366 void drm_gpuvm_put(struct drm_gpuvm *gpuvm);
367 
368 bool drm_gpuvm_range_valid(struct drm_gpuvm *gpuvm, u64 addr, u64 range);
369 bool drm_gpuvm_interval_empty(struct drm_gpuvm *gpuvm, u64 addr, u64 range);
370 
371 struct drm_gem_object *
372 drm_gpuvm_resv_object_alloc(struct drm_device *drm);
373 
374 /**
375  * drm_gpuvm_resv_protected() - indicates whether &DRM_GPUVM_RESV_PROTECTED is
376  * set
377  * @gpuvm: the &drm_gpuvm
378  *
379  * Returns: true if &DRM_GPUVM_RESV_PROTECTED is set, false otherwise.
380  */
381 static inline bool
382 drm_gpuvm_resv_protected(struct drm_gpuvm *gpuvm)
383 {
384 	return gpuvm->flags & DRM_GPUVM_RESV_PROTECTED;
385 }
386 
387 /**
388  * drm_gpuvm_immediate_mode() - indicates whether &DRM_GPUVM_IMMEDIATE_MODE is
389  * set
390  * @gpuvm: the &drm_gpuvm
391  *
392  * Returns: true if &DRM_GPUVM_IMMEDIATE_MODE is set, false otherwise.
393  */
394 static inline bool
395 drm_gpuvm_immediate_mode(struct drm_gpuvm *gpuvm)
396 {
397 	return gpuvm->flags & DRM_GPUVM_IMMEDIATE_MODE;
398 }
399 
400 /**
401  * drm_gpuvm_resv() - returns the &drm_gpuvm's &dma_resv
402  * @gpuvm__: the &drm_gpuvm
403  *
404  * Returns: a pointer to the &drm_gpuvm's shared &dma_resv
405  */
406 #define drm_gpuvm_resv(gpuvm__) ((gpuvm__)->r_obj->resv)
407 
408 /**
409  * drm_gpuvm_resv_obj() - returns the &drm_gem_object holding the &drm_gpuvm's
410  * &dma_resv
411  * @gpuvm__: the &drm_gpuvm
412  *
413  * Returns: a pointer to the &drm_gem_object holding the &drm_gpuvm's shared
414  * &dma_resv
415  */
416 #define drm_gpuvm_resv_obj(gpuvm__) ((gpuvm__)->r_obj)
417 
418 #define drm_gpuvm_resv_held(gpuvm__) \
419 	dma_resv_held(drm_gpuvm_resv(gpuvm__))
420 
421 #define drm_gpuvm_resv_assert_held(gpuvm__) \
422 	dma_resv_assert_held(drm_gpuvm_resv(gpuvm__))
423 
424 #define drm_gpuvm_resv_held(gpuvm__) \
425 	dma_resv_held(drm_gpuvm_resv(gpuvm__))
426 
427 #define drm_gpuvm_resv_assert_held(gpuvm__) \
428 	dma_resv_assert_held(drm_gpuvm_resv(gpuvm__))
429 
430 /**
431  * drm_gpuvm_is_extobj() - indicates whether the given &drm_gem_object is an
432  * external object
433  * @gpuvm: the &drm_gpuvm to check
434  * @obj: the &drm_gem_object to check
435  *
436  * Returns: true if the &drm_gem_object &dma_resv differs from the
437  * &drm_gpuvms &dma_resv, false otherwise
438  */
439 static inline bool
440 drm_gpuvm_is_extobj(struct drm_gpuvm *gpuvm,
441 		    struct drm_gem_object *obj)
442 {
443 	return obj && obj->resv != drm_gpuvm_resv(gpuvm);
444 }
445 
446 static inline struct drm_gpuva *
447 __drm_gpuva_next(struct drm_gpuva *va)
448 {
449 	if (va && !list_is_last(&va->rb.entry, &va->vm->rb.list))
450 		return list_next_entry(va, rb.entry);
451 
452 	return NULL;
453 }
454 
455 /**
456  * drm_gpuvm_for_each_va_range() - iterate over a range of &drm_gpuvas
457  * @va__: &drm_gpuva structure to assign to in each iteration step
458  * @gpuvm__: &drm_gpuvm to walk over
459  * @start__: starting offset, the first gpuva will overlap this
460  * @end__: ending offset, the last gpuva will start before this (but may
461  * overlap)
462  *
463  * This iterator walks over all &drm_gpuvas in the &drm_gpuvm that lie
464  * between @start__ and @end__. It is implemented similarly to list_for_each(),
465  * but is using the &drm_gpuvm's internal interval tree to accelerate
466  * the search for the starting &drm_gpuva, and hence isn't safe against removal
467  * of elements. It assumes that @end__ is within (or is the upper limit of) the
468  * &drm_gpuvm. This iterator does not skip over the &drm_gpuvm's
469  * @kernel_alloc_node.
470  */
471 #define drm_gpuvm_for_each_va_range(va__, gpuvm__, start__, end__) \
472 	for (va__ = drm_gpuva_find_first((gpuvm__), (start__), (end__) - (start__)); \
473 	     va__ && (va__->va.addr < (end__)); \
474 	     va__ = __drm_gpuva_next(va__))
475 
476 /**
477  * drm_gpuvm_for_each_va_range_safe() - safely iterate over a range of
478  * &drm_gpuvas
479  * @va__: &drm_gpuva to assign to in each iteration step
480  * @next__: another &drm_gpuva to use as temporary storage
481  * @gpuvm__: &drm_gpuvm to walk over
482  * @start__: starting offset, the first gpuva will overlap this
483  * @end__: ending offset, the last gpuva will start before this (but may
484  * overlap)
485  *
486  * This iterator walks over all &drm_gpuvas in the &drm_gpuvm that lie
487  * between @start__ and @end__. It is implemented similarly to
488  * list_for_each_safe(), but is using the &drm_gpuvm's internal interval
489  * tree to accelerate the search for the starting &drm_gpuva, and hence is safe
490  * against removal of elements. It assumes that @end__ is within (or is the
491  * upper limit of) the &drm_gpuvm. This iterator does not skip over the
492  * &drm_gpuvm's @kernel_alloc_node.
493  */
494 #define drm_gpuvm_for_each_va_range_safe(va__, next__, gpuvm__, start__, end__) \
495 	for (va__ = drm_gpuva_find_first((gpuvm__), (start__), (end__) - (start__)), \
496 	     next__ = __drm_gpuva_next(va__); \
497 	     va__ && (va__->va.addr < (end__)); \
498 	     va__ = next__, next__ = __drm_gpuva_next(va__))
499 
500 /**
501  * drm_gpuvm_for_each_va() - iterate over all &drm_gpuvas
502  * @va__: &drm_gpuva to assign to in each iteration step
503  * @gpuvm__: &drm_gpuvm to walk over
504  *
505  * This iterator walks over all &drm_gpuva structures associated with the given
506  * &drm_gpuvm.
507  */
508 #define drm_gpuvm_for_each_va(va__, gpuvm__) \
509 	list_for_each_entry(va__, &(gpuvm__)->rb.list, rb.entry)
510 
511 /**
512  * drm_gpuvm_for_each_va_safe() - safely iterate over all &drm_gpuvas
513  * @va__: &drm_gpuva to assign to in each iteration step
514  * @next__: another &drm_gpuva to use as temporary storage
515  * @gpuvm__: &drm_gpuvm to walk over
516  *
517  * This iterator walks over all &drm_gpuva structures associated with the given
518  * &drm_gpuvm. It is implemented with list_for_each_entry_safe(), and
519  * hence safe against the removal of elements.
520  */
521 #define drm_gpuvm_for_each_va_safe(va__, next__, gpuvm__) \
522 	list_for_each_entry_safe(va__, next__, &(gpuvm__)->rb.list, rb.entry)
523 
524 /**
525  * struct drm_gpuvm_exec - &drm_gpuvm abstraction of &drm_exec
526  *
527  * This structure should be created on the stack as &drm_exec should be.
528  *
529  * Optionally, @extra can be set in order to lock additional &drm_gem_objects.
530  */
531 struct drm_gpuvm_exec {
532 	/**
533 	 * @exec: the &drm_exec structure
534 	 */
535 	struct drm_exec exec;
536 
537 	/**
538 	 * @flags: the flags for the struct drm_exec
539 	 */
540 	u32 flags;
541 
542 	/**
543 	 * @vm: the &drm_gpuvm to lock its DMA reservations
544 	 */
545 	struct drm_gpuvm *vm;
546 
547 	/**
548 	 * @num_fences: the number of fences to reserve for the &dma_resv of the
549 	 * locked &drm_gem_objects
550 	 */
551 	unsigned int num_fences;
552 
553 	/**
554 	 * @extra: Callback and corresponding private data for the driver to
555 	 * lock arbitrary additional &drm_gem_objects.
556 	 */
557 	struct {
558 		/**
559 		 * @extra.fn: The driver callback to lock additional
560 		 * &drm_gem_objects.
561 		 */
562 		int (*fn)(struct drm_gpuvm_exec *vm_exec);
563 
564 		/**
565 		 * @extra.priv: driver private data for the @fn callback
566 		 */
567 		void *priv;
568 	} extra;
569 };
570 
571 int drm_gpuvm_prepare_vm(struct drm_gpuvm *gpuvm,
572 			 struct drm_exec *exec,
573 			 unsigned int num_fences);
574 
575 int drm_gpuvm_prepare_objects(struct drm_gpuvm *gpuvm,
576 			      struct drm_exec *exec,
577 			      unsigned int num_fences);
578 
579 int drm_gpuvm_prepare_range(struct drm_gpuvm *gpuvm,
580 			    struct drm_exec *exec,
581 			    u64 addr, u64 range,
582 			    unsigned int num_fences);
583 
584 int drm_gpuvm_exec_lock(struct drm_gpuvm_exec *vm_exec);
585 
586 int drm_gpuvm_exec_lock_array(struct drm_gpuvm_exec *vm_exec,
587 			      struct drm_gem_object **objs,
588 			      unsigned int num_objs);
589 
590 int drm_gpuvm_exec_lock_range(struct drm_gpuvm_exec *vm_exec,
591 			      u64 addr, u64 range);
592 
593 /**
594  * drm_gpuvm_exec_unlock() - lock all dma-resv of all assoiciated BOs
595  * @vm_exec: the &drm_gpuvm_exec wrapper
596  *
597  * Releases all dma-resv locks of all &drm_gem_objects previously acquired
598  * through drm_gpuvm_exec_lock() or its variants.
599  *
600  * Returns: 0 on success, negative error code on failure.
601  */
602 static inline void
603 drm_gpuvm_exec_unlock(struct drm_gpuvm_exec *vm_exec)
604 {
605 	drm_exec_fini(&vm_exec->exec);
606 }
607 
608 int drm_gpuvm_validate(struct drm_gpuvm *gpuvm, struct drm_exec *exec);
609 void drm_gpuvm_resv_add_fence(struct drm_gpuvm *gpuvm,
610 			      struct drm_exec *exec,
611 			      struct dma_fence *fence,
612 			      enum dma_resv_usage private_usage,
613 			      enum dma_resv_usage extobj_usage);
614 
615 /**
616  * drm_gpuvm_exec_resv_add_fence() - add fence to private and all extobj
617  * @vm_exec: the &drm_gpuvm_exec wrapper
618  * @fence: fence to add
619  * @private_usage: private dma-resv usage
620  * @extobj_usage: extobj dma-resv usage
621  *
622  * See drm_gpuvm_resv_add_fence().
623  */
624 static inline void
625 drm_gpuvm_exec_resv_add_fence(struct drm_gpuvm_exec *vm_exec,
626 			      struct dma_fence *fence,
627 			      enum dma_resv_usage private_usage,
628 			      enum dma_resv_usage extobj_usage)
629 {
630 	drm_gpuvm_resv_add_fence(vm_exec->vm, &vm_exec->exec, fence,
631 				 private_usage, extobj_usage);
632 }
633 
634 /**
635  * drm_gpuvm_exec_validate() - validate all BOs marked as evicted
636  * @vm_exec: the &drm_gpuvm_exec wrapper
637  *
638  * See drm_gpuvm_validate().
639  *
640  * Returns: 0 on success, negative error code on failure.
641  */
642 static inline int
643 drm_gpuvm_exec_validate(struct drm_gpuvm_exec *vm_exec)
644 {
645 	return drm_gpuvm_validate(vm_exec->vm, &vm_exec->exec);
646 }
647 
648 /**
649  * struct drm_gpuvm_bo - structure representing a &drm_gpuvm and
650  * &drm_gem_object combination
651  *
652  * This structure is an abstraction representing a &drm_gpuvm and
653  * &drm_gem_object combination. It serves as an indirection to accelerate
654  * iterating all &drm_gpuvas within a &drm_gpuvm backed by the same
655  * &drm_gem_object.
656  *
657  * Furthermore it is used cache evicted GEM objects for a certain GPU-VM to
658  * accelerate validation.
659  *
660  * Typically, drivers want to create an instance of a struct drm_gpuvm_bo once
661  * a GEM object is mapped first in a GPU-VM and release the instance once the
662  * last mapping of the GEM object in this GPU-VM is unmapped.
663  */
664 struct drm_gpuvm_bo {
665 	/**
666 	 * @vm: The &drm_gpuvm the @obj is mapped in. This is a reference
667 	 * counted pointer.
668 	 */
669 	struct drm_gpuvm *vm;
670 
671 	/**
672 	 * @obj: The &drm_gem_object being mapped in @vm. This is a reference
673 	 * counted pointer.
674 	 */
675 	struct drm_gem_object *obj;
676 
677 	/**
678 	 * @evicted: Indicates whether the &drm_gem_object is evicted; field
679 	 * protected by the &drm_gem_object's dma-resv lock.
680 	 */
681 	bool evicted;
682 
683 	/**
684 	 * @kref: The reference count for this &drm_gpuvm_bo.
685 	 */
686 	struct kref kref;
687 
688 	/**
689 	 * @list: Structure containing all &list_heads.
690 	 */
691 	struct {
692 		/**
693 		 * @list.gpuva: The list of linked &drm_gpuvas.
694 		 *
695 		 * It is safe to access entries from this list as long as the
696 		 * GEM's gpuva lock is held. See also struct drm_gem_object.
697 		 */
698 		struct list_head gpuva;
699 
700 		/**
701 		 * @list.entry: Structure containing all &list_heads serving as
702 		 * entry.
703 		 */
704 		struct {
705 			/**
706 			 * @list.entry.gem: List entry to attach to the
707 			 * &drm_gem_objects gpuva list.
708 			 */
709 			struct list_head gem;
710 
711 			/**
712 			 * @list.entry.evict: List entry to attach to the
713 			 * &drm_gpuvms extobj list.
714 			 */
715 			struct list_head extobj;
716 
717 			/**
718 			 * @list.entry.evict: List entry to attach to the
719 			 * &drm_gpuvms evict list.
720 			 */
721 			struct list_head evict;
722 
723 			/**
724 			 * @list.entry.bo_defer: List entry to attach to
725 			 * the &drm_gpuvms bo_defer list.
726 			 */
727 			struct llist_node bo_defer;
728 		} entry;
729 	} list;
730 };
731 
732 struct drm_gpuvm_bo *
733 drm_gpuvm_bo_create(struct drm_gpuvm *gpuvm,
734 		    struct drm_gem_object *obj);
735 
736 struct drm_gpuvm_bo *
737 drm_gpuvm_bo_obtain_locked(struct drm_gpuvm *gpuvm,
738 			   struct drm_gem_object *obj);
739 struct drm_gpuvm_bo *
740 drm_gpuvm_bo_obtain_prealloc(struct drm_gpuvm_bo *vm_bo);
741 
742 /**
743  * drm_gpuvm_bo_get() - acquire a struct drm_gpuvm_bo reference
744  * @vm_bo: the &drm_gpuvm_bo to acquire the reference of
745  *
746  * This function acquires an additional reference to @vm_bo. It is illegal to
747  * call this without already holding a reference. No locks required.
748  *
749  * Returns: the &struct vm_bo pointer
750  */
751 static inline struct drm_gpuvm_bo *
752 drm_gpuvm_bo_get(struct drm_gpuvm_bo *vm_bo)
753 {
754 	kref_get(&vm_bo->kref);
755 	return vm_bo;
756 }
757 
758 bool drm_gpuvm_bo_put(struct drm_gpuvm_bo *vm_bo);
759 
760 bool drm_gpuvm_bo_put_deferred(struct drm_gpuvm_bo *vm_bo);
761 void drm_gpuvm_bo_deferred_cleanup(struct drm_gpuvm *gpuvm);
762 
763 struct drm_gpuvm_bo *
764 drm_gpuvm_bo_find(struct drm_gpuvm *gpuvm,
765 		  struct drm_gem_object *obj);
766 
767 void drm_gpuvm_bo_evict(struct drm_gpuvm_bo *vm_bo, bool evict);
768 
769 /**
770  * drm_gpuvm_bo_gem_evict() - add/remove all &drm_gpuvm_bo's in the list
771  * to/from the &drm_gpuvms evicted list
772  * @obj: the &drm_gem_object
773  * @evict: indicates whether @obj is evicted
774  *
775  * See drm_gpuvm_bo_evict().
776  */
777 static inline void
778 drm_gpuvm_bo_gem_evict(struct drm_gem_object *obj, bool evict)
779 {
780 	struct drm_gpuvm_bo *vm_bo;
781 
782 	drm_gem_for_each_gpuvm_bo(vm_bo, obj) {
783 		drm_gem_gpuva_assert_lock_held(vm_bo->vm, obj);
784 		drm_gpuvm_bo_evict(vm_bo, evict);
785 	}
786 }
787 
788 void drm_gpuvm_bo_extobj_add(struct drm_gpuvm_bo *vm_bo);
789 
790 /**
791  * drm_gpuvm_bo_for_each_va() - iterator to walk over a list of &drm_gpuva
792  * @va__: &drm_gpuva structure to assign to in each iteration step
793  * @vm_bo__: the &drm_gpuvm_bo the &drm_gpuva to walk are associated with
794  *
795  * This iterator walks over all &drm_gpuva structures associated with the
796  * &drm_gpuvm_bo.
797  *
798  * The caller must hold the GEM's gpuva lock.
799  */
800 #define drm_gpuvm_bo_for_each_va(va__, vm_bo__) \
801 	list_for_each_entry(va__, &(vm_bo)->list.gpuva, gem.entry)
802 
803 /**
804  * drm_gpuvm_bo_for_each_va_safe() - iterator to safely walk over a list of
805  * &drm_gpuva
806  * @va__: &drm_gpuva structure to assign to in each iteration step
807  * @next__: &next &drm_gpuva to store the next step
808  * @vm_bo__: the &drm_gpuvm_bo the &drm_gpuva to walk are associated with
809  *
810  * This iterator walks over all &drm_gpuva structures associated with the
811  * &drm_gpuvm_bo. It is implemented with list_for_each_entry_safe(), hence
812  * it is save against removal of elements.
813  *
814  * The caller must hold the GEM's gpuva lock.
815  */
816 #define drm_gpuvm_bo_for_each_va_safe(va__, next__, vm_bo__) \
817 	list_for_each_entry_safe(va__, next__, &(vm_bo)->list.gpuva, gem.entry)
818 
819 /**
820  * enum drm_gpuva_op_type - GPU VA operation type
821  *
822  * Operations to alter the GPU VA mappings tracked by the &drm_gpuvm.
823  */
824 enum drm_gpuva_op_type {
825 	/**
826 	 * @DRM_GPUVA_OP_MAP: the map op type
827 	 */
828 	DRM_GPUVA_OP_MAP,
829 
830 	/**
831 	 * @DRM_GPUVA_OP_REMAP: the remap op type
832 	 */
833 	DRM_GPUVA_OP_REMAP,
834 
835 	/**
836 	 * @DRM_GPUVA_OP_UNMAP: the unmap op type
837 	 */
838 	DRM_GPUVA_OP_UNMAP,
839 
840 	/**
841 	 * @DRM_GPUVA_OP_PREFETCH: the prefetch op type
842 	 */
843 	DRM_GPUVA_OP_PREFETCH,
844 
845 	/**
846 	 * @DRM_GPUVA_OP_DRIVER: the driver defined op type
847 	 */
848 	DRM_GPUVA_OP_DRIVER,
849 };
850 
851 /**
852  * struct drm_gpuva_op_map - GPU VA map operation
853  *
854  * This structure represents a single map operation generated by the
855  * DRM GPU VA manager.
856  */
857 struct drm_gpuva_op_map {
858 	/**
859 	 * @va: structure containing address and range of a map
860 	 * operation
861 	 */
862 	struct {
863 		/**
864 		 * @va.addr: the base address of the new mapping
865 		 */
866 		u64 addr;
867 
868 		/**
869 		 * @va.range: the range of the new mapping
870 		 */
871 		u64 range;
872 	} va;
873 
874 	/**
875 	 * @gem: structure containing the &drm_gem_object and its offset
876 	 */
877 	struct {
878 		/**
879 		 * @gem.offset: the offset within the &drm_gem_object
880 		 */
881 		u64 offset;
882 
883 		/**
884 		 * @gem.obj: the &drm_gem_object to map
885 		 */
886 		struct drm_gem_object *obj;
887 	} gem;
888 };
889 
890 /**
891  * struct drm_gpuva_op_unmap - GPU VA unmap operation
892  *
893  * This structure represents a single unmap operation generated by the
894  * DRM GPU VA manager.
895  */
896 struct drm_gpuva_op_unmap {
897 	/**
898 	 * @va: the &drm_gpuva to unmap
899 	 */
900 	struct drm_gpuva *va;
901 
902 	/**
903 	 * @keep:
904 	 *
905 	 * Indicates whether this &drm_gpuva is physically contiguous with the
906 	 * original mapping request.
907 	 *
908 	 * Optionally, if &keep is set, drivers may keep the actual page table
909 	 * mappings for this &drm_gpuva, adding the missing page table entries
910 	 * only and update the &drm_gpuvm accordingly.
911 	 */
912 	bool keep;
913 };
914 
915 /**
916  * struct drm_gpuva_op_remap - GPU VA remap operation
917  *
918  * This represents a single remap operation generated by the DRM GPU VA manager.
919  *
920  * A remap operation is generated when an existing GPU VA mmapping is split up
921  * by inserting a new GPU VA mapping or by partially unmapping existent
922  * mapping(s), hence it consists of a maximum of two map and one unmap
923  * operation.
924  *
925  * The @unmap operation takes care of removing the original existing mapping.
926  * @prev is used to remap the preceding part, @next the subsequent part.
927  *
928  * If either a new mapping's start address is aligned with the start address
929  * of the old mapping or the new mapping's end address is aligned with the
930  * end address of the old mapping, either @prev or @next is NULL.
931  * This will also be the case when the requested mapping begins before the
932  * old mapping's start address or stretches beyond its end address.
933  *
934  * Note, the reason for a dedicated remap operation, rather than arbitrary
935  * unmap and map operations, is to give drivers the chance of extracting driver
936  * specific data for creating the new mappings from the unmap operations's
937  * &drm_gpuva structure which typically is embedded in larger driver specific
938  * structures.
939  */
940 struct drm_gpuva_op_remap {
941 	/**
942 	 * @prev: the preceding part of a split mapping
943 	 */
944 	struct drm_gpuva_op_map *prev;
945 
946 	/**
947 	 * @next: the subsequent part of a split mapping
948 	 */
949 	struct drm_gpuva_op_map *next;
950 
951 	/**
952 	 * @unmap: the unmap operation for the original existing mapping
953 	 */
954 	struct drm_gpuva_op_unmap *unmap;
955 };
956 
957 /**
958  * struct drm_gpuva_op_prefetch - GPU VA prefetch operation
959  *
960  * This structure represents a single prefetch operation generated by the
961  * DRM GPU VA manager.
962  */
963 struct drm_gpuva_op_prefetch {
964 	/**
965 	 * @va: the &drm_gpuva to prefetch
966 	 */
967 	struct drm_gpuva *va;
968 };
969 
970 /**
971  * struct drm_gpuva_op - GPU VA operation
972  *
973  * This structure represents a single generic operation.
974  *
975  * The particular type of the operation is defined by @op.
976  */
977 struct drm_gpuva_op {
978 	/**
979 	 * @entry:
980 	 *
981 	 * The &list_head used to distribute instances of this struct within
982 	 * &drm_gpuva_ops.
983 	 */
984 	struct list_head entry;
985 
986 	/**
987 	 * @op: the type of the operation
988 	 */
989 	enum drm_gpuva_op_type op;
990 
991 	union {
992 		/**
993 		 * @map: the map operation
994 		 */
995 		struct drm_gpuva_op_map map;
996 
997 		/**
998 		 * @remap: the remap operation
999 		 */
1000 		struct drm_gpuva_op_remap remap;
1001 
1002 		/**
1003 		 * @unmap: the unmap operation
1004 		 */
1005 		struct drm_gpuva_op_unmap unmap;
1006 
1007 		/**
1008 		 * @prefetch: the prefetch operation
1009 		 */
1010 		struct drm_gpuva_op_prefetch prefetch;
1011 	};
1012 };
1013 
1014 /**
1015  * struct drm_gpuva_ops - wraps a list of &drm_gpuva_op
1016  */
1017 struct drm_gpuva_ops {
1018 	/**
1019 	 * @list: the &list_head
1020 	 */
1021 	struct list_head list;
1022 };
1023 
1024 /**
1025  * drm_gpuva_for_each_op() - iterator to walk over &drm_gpuva_ops
1026  * @op: &drm_gpuva_op to assign in each iteration step
1027  * @ops: &drm_gpuva_ops to walk
1028  *
1029  * This iterator walks over all ops within a given list of operations.
1030  */
1031 #define drm_gpuva_for_each_op(op, ops) list_for_each_entry(op, &(ops)->list, entry)
1032 
1033 /**
1034  * drm_gpuva_for_each_op_safe() - iterator to safely walk over &drm_gpuva_ops
1035  * @op: &drm_gpuva_op to assign in each iteration step
1036  * @next: &next &drm_gpuva_op to store the next step
1037  * @ops: &drm_gpuva_ops to walk
1038  *
1039  * This iterator walks over all ops within a given list of operations. It is
1040  * implemented with list_for_each_safe(), so save against removal of elements.
1041  */
1042 #define drm_gpuva_for_each_op_safe(op, next, ops) \
1043 	list_for_each_entry_safe(op, next, &(ops)->list, entry)
1044 
1045 /**
1046  * drm_gpuva_for_each_op_from_reverse() - iterate backwards from the given point
1047  * @op: &drm_gpuva_op to assign in each iteration step
1048  * @ops: &drm_gpuva_ops to walk
1049  *
1050  * This iterator walks over all ops within a given list of operations beginning
1051  * from the given operation in reverse order.
1052  */
1053 #define drm_gpuva_for_each_op_from_reverse(op, ops) \
1054 	list_for_each_entry_from_reverse(op, &(ops)->list, entry)
1055 
1056 /**
1057  * drm_gpuva_for_each_op_reverse - iterator to walk over &drm_gpuva_ops in reverse
1058  * @op: &drm_gpuva_op to assign in each iteration step
1059  * @ops: &drm_gpuva_ops to walk
1060  *
1061  * This iterator walks over all ops within a given list of operations in reverse
1062  */
1063 #define drm_gpuva_for_each_op_reverse(op, ops) \
1064 	list_for_each_entry_reverse(op, &(ops)->list, entry)
1065 
1066 /**
1067  * drm_gpuva_first_op() - returns the first &drm_gpuva_op from &drm_gpuva_ops
1068  * @ops: the &drm_gpuva_ops to get the fist &drm_gpuva_op from
1069  */
1070 #define drm_gpuva_first_op(ops) \
1071 	list_first_entry(&(ops)->list, struct drm_gpuva_op, entry)
1072 
1073 /**
1074  * drm_gpuva_last_op() - returns the last &drm_gpuva_op from &drm_gpuva_ops
1075  * @ops: the &drm_gpuva_ops to get the last &drm_gpuva_op from
1076  */
1077 #define drm_gpuva_last_op(ops) \
1078 	list_last_entry(&(ops)->list, struct drm_gpuva_op, entry)
1079 
1080 /**
1081  * drm_gpuva_prev_op() - previous &drm_gpuva_op in the list
1082  * @op: the current &drm_gpuva_op
1083  */
1084 #define drm_gpuva_prev_op(op) list_prev_entry(op, entry)
1085 
1086 /**
1087  * drm_gpuva_next_op() - next &drm_gpuva_op in the list
1088  * @op: the current &drm_gpuva_op
1089  */
1090 #define drm_gpuva_next_op(op) list_next_entry(op, entry)
1091 
1092 /**
1093  * struct drm_gpuvm_map_req - arguments passed to drm_gpuvm_sm_map[_ops_create]()
1094  */
1095 struct drm_gpuvm_map_req {
1096 	/**
1097 	 * @map: struct drm_gpuva_op_map
1098 	 */
1099 	struct drm_gpuva_op_map map;
1100 };
1101 
1102 struct drm_gpuva_ops *
1103 drm_gpuvm_sm_map_ops_create(struct drm_gpuvm *gpuvm,
1104 			    const struct drm_gpuvm_map_req *req);
1105 struct drm_gpuva_ops *
1106 drm_gpuvm_madvise_ops_create(struct drm_gpuvm *gpuvm,
1107 			     const struct drm_gpuvm_map_req *req);
1108 
1109 struct drm_gpuva_ops *
1110 drm_gpuvm_sm_unmap_ops_create(struct drm_gpuvm *gpuvm,
1111 			      u64 addr, u64 range);
1112 
1113 struct drm_gpuva_ops *
1114 drm_gpuvm_prefetch_ops_create(struct drm_gpuvm *gpuvm,
1115 				 u64 addr, u64 range);
1116 
1117 struct drm_gpuva_ops *
1118 drm_gpuvm_bo_unmap_ops_create(struct drm_gpuvm_bo *vm_bo);
1119 
1120 void drm_gpuva_ops_free(struct drm_gpuvm *gpuvm,
1121 			struct drm_gpuva_ops *ops);
1122 
1123 static inline void drm_gpuva_init_from_op(struct drm_gpuva *va,
1124 					  const struct drm_gpuva_op_map *op)
1125 {
1126 	va->va.addr = op->va.addr;
1127 	va->va.range = op->va.range;
1128 	va->gem.obj = op->gem.obj;
1129 	va->gem.offset = op->gem.offset;
1130 }
1131 
1132 /**
1133  * struct drm_gpuvm_ops - callbacks for split/merge steps
1134  *
1135  * This structure defines the callbacks used by &drm_gpuvm_sm_map and
1136  * &drm_gpuvm_sm_unmap to provide the split/merge steps for map and unmap
1137  * operations to drivers.
1138  */
1139 struct drm_gpuvm_ops {
1140 	/**
1141 	 * @vm_free: called when the last reference of a struct drm_gpuvm is
1142 	 * dropped
1143 	 *
1144 	 * This callback is mandatory.
1145 	 */
1146 	void (*vm_free)(struct drm_gpuvm *gpuvm);
1147 
1148 	/**
1149 	 * @op_alloc: called when the &drm_gpuvm allocates
1150 	 * a struct drm_gpuva_op
1151 	 *
1152 	 * Some drivers may want to embed struct drm_gpuva_op into driver
1153 	 * specific structures. By implementing this callback drivers can
1154 	 * allocate memory accordingly.
1155 	 *
1156 	 * This callback is optional.
1157 	 */
1158 	struct drm_gpuva_op *(*op_alloc)(void);
1159 
1160 	/**
1161 	 * @op_free: called when the &drm_gpuvm frees a
1162 	 * struct drm_gpuva_op
1163 	 *
1164 	 * Some drivers may want to embed struct drm_gpuva_op into driver
1165 	 * specific structures. By implementing this callback drivers can
1166 	 * free the previously allocated memory accordingly.
1167 	 *
1168 	 * This callback is optional.
1169 	 */
1170 	void (*op_free)(struct drm_gpuva_op *op);
1171 
1172 	/**
1173 	 * @vm_bo_alloc: called when the &drm_gpuvm allocates
1174 	 * a struct drm_gpuvm_bo
1175 	 *
1176 	 * Some drivers may want to embed struct drm_gpuvm_bo into driver
1177 	 * specific structures. By implementing this callback drivers can
1178 	 * allocate memory accordingly.
1179 	 *
1180 	 * This callback is optional.
1181 	 */
1182 	struct drm_gpuvm_bo *(*vm_bo_alloc)(void);
1183 
1184 	/**
1185 	 * @vm_bo_free: called when the &drm_gpuvm frees a
1186 	 * struct drm_gpuvm_bo
1187 	 *
1188 	 * Some drivers may want to embed struct drm_gpuvm_bo into driver
1189 	 * specific structures. By implementing this callback drivers can
1190 	 * free the previously allocated memory accordingly.
1191 	 *
1192 	 * This callback is optional.
1193 	 */
1194 	void (*vm_bo_free)(struct drm_gpuvm_bo *vm_bo);
1195 
1196 	/**
1197 	 * @vm_bo_validate: called from drm_gpuvm_validate()
1198 	 *
1199 	 * Drivers receive this callback for every evicted &drm_gem_object being
1200 	 * mapped in the corresponding &drm_gpuvm.
1201 	 *
1202 	 * Typically, drivers would call their driver specific variant of
1203 	 * ttm_bo_validate() from within this callback.
1204 	 */
1205 	int (*vm_bo_validate)(struct drm_gpuvm_bo *vm_bo,
1206 			      struct drm_exec *exec);
1207 
1208 	/**
1209 	 * @sm_step_map: called from &drm_gpuvm_sm_map to finally insert the
1210 	 * mapping once all previous steps were completed
1211 	 *
1212 	 * The &priv pointer matches the one the driver passed to
1213 	 * &drm_gpuvm_sm_map or &drm_gpuvm_sm_unmap, respectively.
1214 	 *
1215 	 * Can be NULL if &drm_gpuvm_sm_map is used.
1216 	 */
1217 	int (*sm_step_map)(struct drm_gpuva_op *op, void *priv);
1218 
1219 	/**
1220 	 * @sm_step_remap: called from &drm_gpuvm_sm_map and
1221 	 * &drm_gpuvm_sm_unmap to split up an existent mapping
1222 	 *
1223 	 * This callback is called when existent mapping needs to be split up.
1224 	 * This is the case when either a newly requested mapping overlaps or
1225 	 * is enclosed by an existent mapping or a partial unmap of an existent
1226 	 * mapping is requested.
1227 	 *
1228 	 * The &priv pointer matches the one the driver passed to
1229 	 * &drm_gpuvm_sm_map or &drm_gpuvm_sm_unmap, respectively.
1230 	 *
1231 	 * Can be NULL if neither &drm_gpuvm_sm_map nor &drm_gpuvm_sm_unmap is
1232 	 * used.
1233 	 */
1234 	int (*sm_step_remap)(struct drm_gpuva_op *op, void *priv);
1235 
1236 	/**
1237 	 * @sm_step_unmap: called from &drm_gpuvm_sm_map and
1238 	 * &drm_gpuvm_sm_unmap to unmap an existing mapping
1239 	 *
1240 	 * This callback is called when existing mapping needs to be unmapped.
1241 	 * This is the case when either a newly requested mapping encloses an
1242 	 * existing mapping or an unmap of an existing mapping is requested.
1243 	 *
1244 	 * The &priv pointer matches the one the driver passed to
1245 	 * &drm_gpuvm_sm_map or &drm_gpuvm_sm_unmap, respectively.
1246 	 *
1247 	 * Can be NULL if neither &drm_gpuvm_sm_map nor &drm_gpuvm_sm_unmap is
1248 	 * used.
1249 	 */
1250 	int (*sm_step_unmap)(struct drm_gpuva_op *op, void *priv);
1251 };
1252 
1253 int drm_gpuvm_sm_map(struct drm_gpuvm *gpuvm, void *priv,
1254 		     const struct drm_gpuvm_map_req *req);
1255 
1256 int drm_gpuvm_sm_unmap(struct drm_gpuvm *gpuvm, void *priv,
1257 		       u64 addr, u64 range);
1258 
1259 int drm_gpuvm_sm_map_exec_lock(struct drm_gpuvm *gpuvm,
1260 			  struct drm_exec *exec, unsigned int num_fences,
1261 			  struct drm_gpuvm_map_req *req);
1262 
1263 int drm_gpuvm_sm_unmap_exec_lock(struct drm_gpuvm *gpuvm, struct drm_exec *exec,
1264 				 u64 req_addr, u64 req_range);
1265 
1266 void drm_gpuva_map(struct drm_gpuvm *gpuvm,
1267 		   struct drm_gpuva *va,
1268 		   const struct drm_gpuva_op_map *op);
1269 
1270 void drm_gpuva_remap(struct drm_gpuva *prev,
1271 		     struct drm_gpuva *next,
1272 		     const struct drm_gpuva_op_remap *op);
1273 
1274 void drm_gpuva_unmap(const struct drm_gpuva_op_unmap *op);
1275 
1276 /**
1277  * drm_gpuva_op_remap_to_unmap_range() - Helper to get the start and range of
1278  * the unmap stage of a remap op.
1279  * @op: Remap op.
1280  * @start_addr: Output pointer for the start of the required unmap.
1281  * @range: Output pointer for the length of the required unmap.
1282  *
1283  * The given start address and range will be set such that they represent the
1284  * range of the address space that was previously covered by the mapping being
1285  * re-mapped, but is now empty.
1286  */
1287 static inline void
1288 drm_gpuva_op_remap_to_unmap_range(const struct drm_gpuva_op_remap *op,
1289 				  u64 *start_addr, u64 *range)
1290 {
1291 	const u64 va_start = op->prev ?
1292 			     op->prev->va.addr + op->prev->va.range :
1293 			     op->unmap->va->va.addr;
1294 	const u64 va_end = op->next ?
1295 			   op->next->va.addr :
1296 			   op->unmap->va->va.addr + op->unmap->va->va.range;
1297 
1298 	if (start_addr)
1299 		*start_addr = va_start;
1300 	if (range)
1301 		*range = va_end - va_start;
1302 }
1303 
1304 #endif /* __DRM_GPUVM_H__ */
1305