xref: /openbmc/linux/drivers/gpu/drm/i915/i915_vma.c (revision ea15d3bd)
1 /*
2  * Copyright © 2016 Intel Corporation
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21  * IN THE SOFTWARE.
22  *
23  */
24 
25 #include <linux/sched/mm.h>
26 #include <linux/dma-fence-array.h>
27 #include <drm/drm_gem.h>
28 
29 #include "display/intel_frontbuffer.h"
30 #include "gem/i915_gem_lmem.h"
31 #include "gem/i915_gem_tiling.h"
32 #include "gt/intel_engine.h"
33 #include "gt/intel_engine_heartbeat.h"
34 #include "gt/intel_gt.h"
35 #include "gt/intel_gt_requests.h"
36 
37 #include "i915_drv.h"
38 #include "i915_gem_evict.h"
39 #include "i915_sw_fence_work.h"
40 #include "i915_trace.h"
41 #include "i915_vma.h"
42 #include "i915_vma_resource.h"
43 
44 static inline void assert_vma_held_evict(const struct i915_vma *vma)
45 {
46 	/*
47 	 * We may be forced to unbind when the vm is dead, to clean it up.
48 	 * This is the only exception to the requirement of the object lock
49 	 * being held.
50 	 */
51 	if (kref_read(&vma->vm->ref))
52 		assert_object_held_shared(vma->obj);
53 }
54 
55 static struct kmem_cache *slab_vmas;
56 
57 static struct i915_vma *i915_vma_alloc(void)
58 {
59 	return kmem_cache_zalloc(slab_vmas, GFP_KERNEL);
60 }
61 
62 static void i915_vma_free(struct i915_vma *vma)
63 {
64 	return kmem_cache_free(slab_vmas, vma);
65 }
66 
67 #if IS_ENABLED(CONFIG_DRM_I915_ERRLOG_GEM) && IS_ENABLED(CONFIG_DRM_DEBUG_MM)
68 
69 #include <linux/stackdepot.h>
70 
71 static void vma_print_allocator(struct i915_vma *vma, const char *reason)
72 {
73 	char buf[512];
74 
75 	if (!vma->node.stack) {
76 		DRM_DEBUG_DRIVER("vma.node [%08llx + %08llx] %s: unknown owner\n",
77 				 vma->node.start, vma->node.size, reason);
78 		return;
79 	}
80 
81 	stack_depot_snprint(vma->node.stack, buf, sizeof(buf), 0);
82 	DRM_DEBUG_DRIVER("vma.node [%08llx + %08llx] %s: inserted at %s\n",
83 			 vma->node.start, vma->node.size, reason, buf);
84 }
85 
86 #else
87 
88 static void vma_print_allocator(struct i915_vma *vma, const char *reason)
89 {
90 }
91 
92 #endif
93 
94 static inline struct i915_vma *active_to_vma(struct i915_active *ref)
95 {
96 	return container_of(ref, typeof(struct i915_vma), active);
97 }
98 
99 static int __i915_vma_active(struct i915_active *ref)
100 {
101 	return i915_vma_tryget(active_to_vma(ref)) ? 0 : -ENOENT;
102 }
103 
104 static void __i915_vma_retire(struct i915_active *ref)
105 {
106 	i915_vma_put(active_to_vma(ref));
107 }
108 
109 static struct i915_vma *
110 vma_create(struct drm_i915_gem_object *obj,
111 	   struct i915_address_space *vm,
112 	   const struct i915_ggtt_view *view)
113 {
114 	struct i915_vma *pos = ERR_PTR(-E2BIG);
115 	struct i915_vma *vma;
116 	struct rb_node *rb, **p;
117 	int err;
118 
119 	/* The aliasing_ppgtt should never be used directly! */
120 	GEM_BUG_ON(vm == &vm->gt->ggtt->alias->vm);
121 
122 	vma = i915_vma_alloc();
123 	if (vma == NULL)
124 		return ERR_PTR(-ENOMEM);
125 
126 	vma->ops = &vm->vma_ops;
127 	vma->obj = obj;
128 	vma->size = obj->base.size;
129 	vma->display_alignment = I915_GTT_MIN_ALIGNMENT;
130 
131 	i915_active_init(&vma->active, __i915_vma_active, __i915_vma_retire, 0);
132 
133 	/* Declare ourselves safe for use inside shrinkers */
134 	if (IS_ENABLED(CONFIG_LOCKDEP)) {
135 		fs_reclaim_acquire(GFP_KERNEL);
136 		might_lock(&vma->active.mutex);
137 		fs_reclaim_release(GFP_KERNEL);
138 	}
139 
140 	INIT_LIST_HEAD(&vma->closed_link);
141 	INIT_LIST_HEAD(&vma->obj_link);
142 	RB_CLEAR_NODE(&vma->obj_node);
143 
144 	if (view && view->type != I915_GGTT_VIEW_NORMAL) {
145 		vma->ggtt_view = *view;
146 		if (view->type == I915_GGTT_VIEW_PARTIAL) {
147 			GEM_BUG_ON(range_overflows_t(u64,
148 						     view->partial.offset,
149 						     view->partial.size,
150 						     obj->base.size >> PAGE_SHIFT));
151 			vma->size = view->partial.size;
152 			vma->size <<= PAGE_SHIFT;
153 			GEM_BUG_ON(vma->size > obj->base.size);
154 		} else if (view->type == I915_GGTT_VIEW_ROTATED) {
155 			vma->size = intel_rotation_info_size(&view->rotated);
156 			vma->size <<= PAGE_SHIFT;
157 		} else if (view->type == I915_GGTT_VIEW_REMAPPED) {
158 			vma->size = intel_remapped_info_size(&view->remapped);
159 			vma->size <<= PAGE_SHIFT;
160 		}
161 	}
162 
163 	if (unlikely(vma->size > vm->total))
164 		goto err_vma;
165 
166 	GEM_BUG_ON(!IS_ALIGNED(vma->size, I915_GTT_PAGE_SIZE));
167 
168 	err = mutex_lock_interruptible(&vm->mutex);
169 	if (err) {
170 		pos = ERR_PTR(err);
171 		goto err_vma;
172 	}
173 
174 	vma->vm = vm;
175 	list_add_tail(&vma->vm_link, &vm->unbound_list);
176 
177 	spin_lock(&obj->vma.lock);
178 	if (i915_is_ggtt(vm)) {
179 		if (unlikely(overflows_type(vma->size, u32)))
180 			goto err_unlock;
181 
182 		vma->fence_size = i915_gem_fence_size(vm->i915, vma->size,
183 						      i915_gem_object_get_tiling(obj),
184 						      i915_gem_object_get_stride(obj));
185 		if (unlikely(vma->fence_size < vma->size || /* overflow */
186 			     vma->fence_size > vm->total))
187 			goto err_unlock;
188 
189 		GEM_BUG_ON(!IS_ALIGNED(vma->fence_size, I915_GTT_MIN_ALIGNMENT));
190 
191 		vma->fence_alignment = i915_gem_fence_alignment(vm->i915, vma->size,
192 								i915_gem_object_get_tiling(obj),
193 								i915_gem_object_get_stride(obj));
194 		GEM_BUG_ON(!is_power_of_2(vma->fence_alignment));
195 
196 		__set_bit(I915_VMA_GGTT_BIT, __i915_vma_flags(vma));
197 	}
198 
199 	rb = NULL;
200 	p = &obj->vma.tree.rb_node;
201 	while (*p) {
202 		long cmp;
203 
204 		rb = *p;
205 		pos = rb_entry(rb, struct i915_vma, obj_node);
206 
207 		/*
208 		 * If the view already exists in the tree, another thread
209 		 * already created a matching vma, so return the older instance
210 		 * and dispose of ours.
211 		 */
212 		cmp = i915_vma_compare(pos, vm, view);
213 		if (cmp < 0)
214 			p = &rb->rb_right;
215 		else if (cmp > 0)
216 			p = &rb->rb_left;
217 		else
218 			goto err_unlock;
219 	}
220 	rb_link_node(&vma->obj_node, rb, p);
221 	rb_insert_color(&vma->obj_node, &obj->vma.tree);
222 
223 	if (i915_vma_is_ggtt(vma))
224 		/*
225 		 * We put the GGTT vma at the start of the vma-list, followed
226 		 * by the ppGGTT vma. This allows us to break early when
227 		 * iterating over only the GGTT vma for an object, see
228 		 * for_each_ggtt_vma()
229 		 */
230 		list_add(&vma->obj_link, &obj->vma.list);
231 	else
232 		list_add_tail(&vma->obj_link, &obj->vma.list);
233 
234 	spin_unlock(&obj->vma.lock);
235 	mutex_unlock(&vm->mutex);
236 
237 	return vma;
238 
239 err_unlock:
240 	spin_unlock(&obj->vma.lock);
241 	list_del_init(&vma->vm_link);
242 	mutex_unlock(&vm->mutex);
243 err_vma:
244 	i915_vma_free(vma);
245 	return pos;
246 }
247 
248 static struct i915_vma *
249 i915_vma_lookup(struct drm_i915_gem_object *obj,
250 	   struct i915_address_space *vm,
251 	   const struct i915_ggtt_view *view)
252 {
253 	struct rb_node *rb;
254 
255 	rb = obj->vma.tree.rb_node;
256 	while (rb) {
257 		struct i915_vma *vma = rb_entry(rb, struct i915_vma, obj_node);
258 		long cmp;
259 
260 		cmp = i915_vma_compare(vma, vm, view);
261 		if (cmp == 0)
262 			return vma;
263 
264 		if (cmp < 0)
265 			rb = rb->rb_right;
266 		else
267 			rb = rb->rb_left;
268 	}
269 
270 	return NULL;
271 }
272 
273 /**
274  * i915_vma_instance - return the singleton instance of the VMA
275  * @obj: parent &struct drm_i915_gem_object to be mapped
276  * @vm: address space in which the mapping is located
277  * @view: additional mapping requirements
278  *
279  * i915_vma_instance() looks up an existing VMA of the @obj in the @vm with
280  * the same @view characteristics. If a match is not found, one is created.
281  * Once created, the VMA is kept until either the object is freed, or the
282  * address space is closed.
283  *
284  * Returns the vma, or an error pointer.
285  */
286 struct i915_vma *
287 i915_vma_instance(struct drm_i915_gem_object *obj,
288 		  struct i915_address_space *vm,
289 		  const struct i915_ggtt_view *view)
290 {
291 	struct i915_vma *vma;
292 
293 	GEM_BUG_ON(view && !i915_is_ggtt_or_dpt(vm));
294 	GEM_BUG_ON(!kref_read(&vm->ref));
295 
296 	spin_lock(&obj->vma.lock);
297 	vma = i915_vma_lookup(obj, vm, view);
298 	spin_unlock(&obj->vma.lock);
299 
300 	/* vma_create() will resolve the race if another creates the vma */
301 	if (unlikely(!vma))
302 		vma = vma_create(obj, vm, view);
303 
304 	GEM_BUG_ON(!IS_ERR(vma) && i915_vma_compare(vma, vm, view));
305 	return vma;
306 }
307 
308 struct i915_vma_work {
309 	struct dma_fence_work base;
310 	struct i915_address_space *vm;
311 	struct i915_vm_pt_stash stash;
312 	struct i915_vma_resource *vma_res;
313 	struct drm_i915_gem_object *obj;
314 	struct i915_sw_dma_fence_cb cb;
315 	enum i915_cache_level cache_level;
316 	unsigned int flags;
317 };
318 
319 static void __vma_bind(struct dma_fence_work *work)
320 {
321 	struct i915_vma_work *vw = container_of(work, typeof(*vw), base);
322 	struct i915_vma_resource *vma_res = vw->vma_res;
323 
324 	/*
325 	 * We are about the bind the object, which must mean we have already
326 	 * signaled the work to potentially clear/move the pages underneath. If
327 	 * something went wrong at that stage then the object should have
328 	 * unknown_state set, in which case we need to skip the bind.
329 	 */
330 	if (i915_gem_object_has_unknown_state(vw->obj))
331 		return;
332 
333 	vma_res->ops->bind_vma(vma_res->vm, &vw->stash,
334 			       vma_res, vw->cache_level, vw->flags);
335 }
336 
337 static void __vma_release(struct dma_fence_work *work)
338 {
339 	struct i915_vma_work *vw = container_of(work, typeof(*vw), base);
340 
341 	if (vw->obj)
342 		i915_gem_object_put(vw->obj);
343 
344 	i915_vm_free_pt_stash(vw->vm, &vw->stash);
345 	if (vw->vma_res)
346 		i915_vma_resource_put(vw->vma_res);
347 }
348 
349 static const struct dma_fence_work_ops bind_ops = {
350 	.name = "bind",
351 	.work = __vma_bind,
352 	.release = __vma_release,
353 };
354 
355 struct i915_vma_work *i915_vma_work(void)
356 {
357 	struct i915_vma_work *vw;
358 
359 	vw = kzalloc(sizeof(*vw), GFP_KERNEL);
360 	if (!vw)
361 		return NULL;
362 
363 	dma_fence_work_init(&vw->base, &bind_ops);
364 	vw->base.dma.error = -EAGAIN; /* disable the worker by default */
365 
366 	return vw;
367 }
368 
369 int i915_vma_wait_for_bind(struct i915_vma *vma)
370 {
371 	int err = 0;
372 
373 	if (rcu_access_pointer(vma->active.excl.fence)) {
374 		struct dma_fence *fence;
375 
376 		rcu_read_lock();
377 		fence = dma_fence_get_rcu_safe(&vma->active.excl.fence);
378 		rcu_read_unlock();
379 		if (fence) {
380 			err = dma_fence_wait(fence, true);
381 			dma_fence_put(fence);
382 		}
383 	}
384 
385 	return err;
386 }
387 
388 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)
389 static int i915_vma_verify_bind_complete(struct i915_vma *vma)
390 {
391 	struct dma_fence *fence = i915_active_fence_get(&vma->active.excl);
392 	int err;
393 
394 	if (!fence)
395 		return 0;
396 
397 	if (dma_fence_is_signaled(fence))
398 		err = fence->error;
399 	else
400 		err = -EBUSY;
401 
402 	dma_fence_put(fence);
403 
404 	return err;
405 }
406 #else
407 #define i915_vma_verify_bind_complete(_vma) 0
408 #endif
409 
410 I915_SELFTEST_EXPORT void
411 i915_vma_resource_init_from_vma(struct i915_vma_resource *vma_res,
412 				struct i915_vma *vma)
413 {
414 	struct drm_i915_gem_object *obj = vma->obj;
415 
416 	i915_vma_resource_init(vma_res, vma->vm, vma->pages, &vma->page_sizes,
417 			       obj->mm.rsgt, i915_gem_object_is_readonly(obj),
418 			       i915_gem_object_is_lmem(obj), obj->mm.region,
419 			       vma->ops, vma->private, vma->node.start,
420 			       vma->node.size, vma->size);
421 }
422 
423 /**
424  * i915_vma_bind - Sets up PTEs for an VMA in it's corresponding address space.
425  * @vma: VMA to map
426  * @cache_level: mapping cache level
427  * @flags: flags like global or local mapping
428  * @work: preallocated worker for allocating and binding the PTE
429  * @vma_res: pointer to a preallocated vma resource. The resource is either
430  * consumed or freed.
431  *
432  * DMA addresses are taken from the scatter-gather table of this object (or of
433  * this VMA in case of non-default GGTT views) and PTE entries set up.
434  * Note that DMA addresses are also the only part of the SG table we care about.
435  */
436 int i915_vma_bind(struct i915_vma *vma,
437 		  enum i915_cache_level cache_level,
438 		  u32 flags,
439 		  struct i915_vma_work *work,
440 		  struct i915_vma_resource *vma_res)
441 {
442 	u32 bind_flags;
443 	u32 vma_flags;
444 	int ret;
445 
446 	lockdep_assert_held(&vma->vm->mutex);
447 	GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
448 	GEM_BUG_ON(vma->size > vma->node.size);
449 
450 	if (GEM_DEBUG_WARN_ON(range_overflows(vma->node.start,
451 					      vma->node.size,
452 					      vma->vm->total))) {
453 		i915_vma_resource_free(vma_res);
454 		return -ENODEV;
455 	}
456 
457 	if (GEM_DEBUG_WARN_ON(!flags)) {
458 		i915_vma_resource_free(vma_res);
459 		return -EINVAL;
460 	}
461 
462 	bind_flags = flags;
463 	bind_flags &= I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND;
464 
465 	vma_flags = atomic_read(&vma->flags);
466 	vma_flags &= I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND;
467 
468 	bind_flags &= ~vma_flags;
469 	if (bind_flags == 0) {
470 		i915_vma_resource_free(vma_res);
471 		return 0;
472 	}
473 
474 	GEM_BUG_ON(!atomic_read(&vma->pages_count));
475 
476 	/* Wait for or await async unbinds touching our range */
477 	if (work && bind_flags & vma->vm->bind_async_flags)
478 		ret = i915_vma_resource_bind_dep_await(vma->vm,
479 						       &work->base.chain,
480 						       vma->node.start,
481 						       vma->node.size,
482 						       true,
483 						       GFP_NOWAIT |
484 						       __GFP_RETRY_MAYFAIL |
485 						       __GFP_NOWARN);
486 	else
487 		ret = i915_vma_resource_bind_dep_sync(vma->vm, vma->node.start,
488 						      vma->node.size, true);
489 	if (ret) {
490 		i915_vma_resource_free(vma_res);
491 		return ret;
492 	}
493 
494 	if (vma->resource || !vma_res) {
495 		/* Rebinding with an additional I915_VMA_*_BIND */
496 		GEM_WARN_ON(!vma_flags);
497 		i915_vma_resource_free(vma_res);
498 	} else {
499 		i915_vma_resource_init_from_vma(vma_res, vma);
500 		vma->resource = vma_res;
501 	}
502 	trace_i915_vma_bind(vma, bind_flags);
503 	if (work && bind_flags & vma->vm->bind_async_flags) {
504 		struct dma_fence *prev;
505 
506 		work->vma_res = i915_vma_resource_get(vma->resource);
507 		work->cache_level = cache_level;
508 		work->flags = bind_flags;
509 
510 		/*
511 		 * Note we only want to chain up to the migration fence on
512 		 * the pages (not the object itself). As we don't track that,
513 		 * yet, we have to use the exclusive fence instead.
514 		 *
515 		 * Also note that we do not want to track the async vma as
516 		 * part of the obj->resv->excl_fence as it only affects
517 		 * execution and not content or object's backing store lifetime.
518 		 */
519 		prev = i915_active_set_exclusive(&vma->active, &work->base.dma);
520 		if (prev) {
521 			__i915_sw_fence_await_dma_fence(&work->base.chain,
522 							prev,
523 							&work->cb);
524 			dma_fence_put(prev);
525 		}
526 
527 		work->base.dma.error = 0; /* enable the queue_work() */
528 		work->obj = i915_gem_object_get(vma->obj);
529 	} else {
530 		ret = i915_gem_object_wait_moving_fence(vma->obj, true);
531 		if (ret) {
532 			i915_vma_resource_free(vma->resource);
533 			vma->resource = NULL;
534 
535 			return ret;
536 		}
537 		vma->ops->bind_vma(vma->vm, NULL, vma->resource, cache_level,
538 				   bind_flags);
539 	}
540 
541 	set_bit(I915_BO_WAS_BOUND_BIT, &vma->obj->flags);
542 
543 	atomic_or(bind_flags, &vma->flags);
544 	return 0;
545 }
546 
547 void __iomem *i915_vma_pin_iomap(struct i915_vma *vma)
548 {
549 	void __iomem *ptr;
550 	int err;
551 
552 	if (WARN_ON_ONCE(vma->obj->flags & I915_BO_ALLOC_GPU_ONLY))
553 		return IOMEM_ERR_PTR(-EINVAL);
554 
555 	GEM_BUG_ON(!i915_vma_is_ggtt(vma));
556 	GEM_BUG_ON(!i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND));
557 	GEM_BUG_ON(i915_vma_verify_bind_complete(vma));
558 
559 	ptr = READ_ONCE(vma->iomap);
560 	if (ptr == NULL) {
561 		/*
562 		 * TODO: consider just using i915_gem_object_pin_map() for lmem
563 		 * instead, which already supports mapping non-contiguous chunks
564 		 * of pages, that way we can also drop the
565 		 * I915_BO_ALLOC_CONTIGUOUS when allocating the object.
566 		 */
567 		if (i915_gem_object_is_lmem(vma->obj)) {
568 			ptr = i915_gem_object_lmem_io_map(vma->obj, 0,
569 							  vma->obj->base.size);
570 		} else if (i915_vma_is_map_and_fenceable(vma)) {
571 			ptr = io_mapping_map_wc(&i915_vm_to_ggtt(vma->vm)->iomap,
572 						vma->node.start,
573 						vma->node.size);
574 		} else {
575 			ptr = (void __iomem *)
576 				i915_gem_object_pin_map(vma->obj, I915_MAP_WC);
577 			if (IS_ERR(ptr)) {
578 				err = PTR_ERR(ptr);
579 				goto err;
580 			}
581 			ptr = page_pack_bits(ptr, 1);
582 		}
583 
584 		if (ptr == NULL) {
585 			err = -ENOMEM;
586 			goto err;
587 		}
588 
589 		if (unlikely(cmpxchg(&vma->iomap, NULL, ptr))) {
590 			if (page_unmask_bits(ptr))
591 				__i915_gem_object_release_map(vma->obj);
592 			else
593 				io_mapping_unmap(ptr);
594 			ptr = vma->iomap;
595 		}
596 	}
597 
598 	__i915_vma_pin(vma);
599 
600 	err = i915_vma_pin_fence(vma);
601 	if (err)
602 		goto err_unpin;
603 
604 	i915_vma_set_ggtt_write(vma);
605 
606 	/* NB Access through the GTT requires the device to be awake. */
607 	return page_mask_bits(ptr);
608 
609 err_unpin:
610 	__i915_vma_unpin(vma);
611 err:
612 	return IOMEM_ERR_PTR(err);
613 }
614 
615 void i915_vma_flush_writes(struct i915_vma *vma)
616 {
617 	if (i915_vma_unset_ggtt_write(vma))
618 		intel_gt_flush_ggtt_writes(vma->vm->gt);
619 }
620 
621 void i915_vma_unpin_iomap(struct i915_vma *vma)
622 {
623 	GEM_BUG_ON(vma->iomap == NULL);
624 
625 	/* XXX We keep the mapping until __i915_vma_unbind()/evict() */
626 
627 	i915_vma_flush_writes(vma);
628 
629 	i915_vma_unpin_fence(vma);
630 	i915_vma_unpin(vma);
631 }
632 
633 void i915_vma_unpin_and_release(struct i915_vma **p_vma, unsigned int flags)
634 {
635 	struct i915_vma *vma;
636 	struct drm_i915_gem_object *obj;
637 
638 	vma = fetch_and_zero(p_vma);
639 	if (!vma)
640 		return;
641 
642 	obj = vma->obj;
643 	GEM_BUG_ON(!obj);
644 
645 	i915_vma_unpin(vma);
646 
647 	if (flags & I915_VMA_RELEASE_MAP)
648 		i915_gem_object_unpin_map(obj);
649 
650 	i915_gem_object_put(obj);
651 }
652 
653 bool i915_vma_misplaced(const struct i915_vma *vma,
654 			u64 size, u64 alignment, u64 flags)
655 {
656 	if (!drm_mm_node_allocated(&vma->node))
657 		return false;
658 
659 	if (test_bit(I915_VMA_ERROR_BIT, __i915_vma_flags(vma)))
660 		return true;
661 
662 	if (vma->node.size < size)
663 		return true;
664 
665 	GEM_BUG_ON(alignment && !is_power_of_2(alignment));
666 	if (alignment && !IS_ALIGNED(vma->node.start, alignment))
667 		return true;
668 
669 	if (flags & PIN_MAPPABLE && !i915_vma_is_map_and_fenceable(vma))
670 		return true;
671 
672 	if (flags & PIN_OFFSET_BIAS &&
673 	    vma->node.start < (flags & PIN_OFFSET_MASK))
674 		return true;
675 
676 	if (flags & PIN_OFFSET_FIXED &&
677 	    vma->node.start != (flags & PIN_OFFSET_MASK))
678 		return true;
679 
680 	return false;
681 }
682 
683 void __i915_vma_set_map_and_fenceable(struct i915_vma *vma)
684 {
685 	bool mappable, fenceable;
686 
687 	GEM_BUG_ON(!i915_vma_is_ggtt(vma));
688 	GEM_BUG_ON(!vma->fence_size);
689 
690 	fenceable = (vma->node.size >= vma->fence_size &&
691 		     IS_ALIGNED(vma->node.start, vma->fence_alignment));
692 
693 	mappable = vma->node.start + vma->fence_size <= i915_vm_to_ggtt(vma->vm)->mappable_end;
694 
695 	if (mappable && fenceable)
696 		set_bit(I915_VMA_CAN_FENCE_BIT, __i915_vma_flags(vma));
697 	else
698 		clear_bit(I915_VMA_CAN_FENCE_BIT, __i915_vma_flags(vma));
699 }
700 
701 bool i915_gem_valid_gtt_space(struct i915_vma *vma, unsigned long color)
702 {
703 	struct drm_mm_node *node = &vma->node;
704 	struct drm_mm_node *other;
705 
706 	/*
707 	 * On some machines we have to be careful when putting differing types
708 	 * of snoopable memory together to avoid the prefetcher crossing memory
709 	 * domains and dying. During vm initialisation, we decide whether or not
710 	 * these constraints apply and set the drm_mm.color_adjust
711 	 * appropriately.
712 	 */
713 	if (!i915_vm_has_cache_coloring(vma->vm))
714 		return true;
715 
716 	/* Only valid to be called on an already inserted vma */
717 	GEM_BUG_ON(!drm_mm_node_allocated(node));
718 	GEM_BUG_ON(list_empty(&node->node_list));
719 
720 	other = list_prev_entry(node, node_list);
721 	if (i915_node_color_differs(other, color) &&
722 	    !drm_mm_hole_follows(other))
723 		return false;
724 
725 	other = list_next_entry(node, node_list);
726 	if (i915_node_color_differs(other, color) &&
727 	    !drm_mm_hole_follows(node))
728 		return false;
729 
730 	return true;
731 }
732 
733 /**
734  * i915_vma_insert - finds a slot for the vma in its address space
735  * @vma: the vma
736  * @size: requested size in bytes (can be larger than the VMA)
737  * @alignment: required alignment
738  * @flags: mask of PIN_* flags to use
739  *
740  * First we try to allocate some free space that meets the requirements for
741  * the VMA. Failiing that, if the flags permit, it will evict an old VMA,
742  * preferrably the oldest idle entry to make room for the new VMA.
743  *
744  * Returns:
745  * 0 on success, negative error code otherwise.
746  */
747 static int
748 i915_vma_insert(struct i915_vma *vma, struct i915_gem_ww_ctx *ww,
749 		u64 size, u64 alignment, u64 flags)
750 {
751 	unsigned long color;
752 	u64 start, end;
753 	int ret;
754 
755 	GEM_BUG_ON(i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND));
756 	GEM_BUG_ON(drm_mm_node_allocated(&vma->node));
757 
758 	size = max(size, vma->size);
759 	alignment = max(alignment, vma->display_alignment);
760 	if (flags & PIN_MAPPABLE) {
761 		size = max_t(typeof(size), size, vma->fence_size);
762 		alignment = max_t(typeof(alignment),
763 				  alignment, vma->fence_alignment);
764 	}
765 
766 	GEM_BUG_ON(!IS_ALIGNED(size, I915_GTT_PAGE_SIZE));
767 	GEM_BUG_ON(!IS_ALIGNED(alignment, I915_GTT_MIN_ALIGNMENT));
768 	GEM_BUG_ON(!is_power_of_2(alignment));
769 
770 	start = flags & PIN_OFFSET_BIAS ? flags & PIN_OFFSET_MASK : 0;
771 	GEM_BUG_ON(!IS_ALIGNED(start, I915_GTT_PAGE_SIZE));
772 
773 	end = vma->vm->total;
774 	if (flags & PIN_MAPPABLE)
775 		end = min_t(u64, end, i915_vm_to_ggtt(vma->vm)->mappable_end);
776 	if (flags & PIN_ZONE_4G)
777 		end = min_t(u64, end, (1ULL << 32) - I915_GTT_PAGE_SIZE);
778 	GEM_BUG_ON(!IS_ALIGNED(end, I915_GTT_PAGE_SIZE));
779 
780 	alignment = max(alignment, i915_vm_obj_min_alignment(vma->vm, vma->obj));
781 	/*
782 	 * for compact-pt we round up the reservation to prevent
783 	 * any smaller pages being used within the same PDE
784 	 */
785 	if (NEEDS_COMPACT_PT(vma->vm->i915))
786 		size = round_up(size, alignment);
787 
788 	/* If binding the object/GGTT view requires more space than the entire
789 	 * aperture has, reject it early before evicting everything in a vain
790 	 * attempt to find space.
791 	 */
792 	if (size > end) {
793 		DRM_DEBUG("Attempting to bind an object larger than the aperture: request=%llu > %s aperture=%llu\n",
794 			  size, flags & PIN_MAPPABLE ? "mappable" : "total",
795 			  end);
796 		return -ENOSPC;
797 	}
798 
799 	color = 0;
800 
801 	if (i915_vm_has_cache_coloring(vma->vm))
802 		color = vma->obj->cache_level;
803 
804 	if (flags & PIN_OFFSET_FIXED) {
805 		u64 offset = flags & PIN_OFFSET_MASK;
806 		if (!IS_ALIGNED(offset, alignment) ||
807 		    range_overflows(offset, size, end))
808 			return -EINVAL;
809 
810 		ret = i915_gem_gtt_reserve(vma->vm, ww, &vma->node,
811 					   size, offset, color,
812 					   flags);
813 		if (ret)
814 			return ret;
815 	} else {
816 		/*
817 		 * We only support huge gtt pages through the 48b PPGTT,
818 		 * however we also don't want to force any alignment for
819 		 * objects which need to be tightly packed into the low 32bits.
820 		 *
821 		 * Note that we assume that GGTT are limited to 4GiB for the
822 		 * forseeable future. See also i915_ggtt_offset().
823 		 */
824 		if (upper_32_bits(end - 1) &&
825 		    vma->page_sizes.sg > I915_GTT_PAGE_SIZE) {
826 			/*
827 			 * We can't mix 64K and 4K PTEs in the same page-table
828 			 * (2M block), and so to avoid the ugliness and
829 			 * complexity of coloring we opt for just aligning 64K
830 			 * objects to 2M.
831 			 */
832 			u64 page_alignment =
833 				rounddown_pow_of_two(vma->page_sizes.sg |
834 						     I915_GTT_PAGE_SIZE_2M);
835 
836 			/*
837 			 * Check we don't expand for the limited Global GTT
838 			 * (mappable aperture is even more precious!). This
839 			 * also checks that we exclude the aliasing-ppgtt.
840 			 */
841 			GEM_BUG_ON(i915_vma_is_ggtt(vma));
842 
843 			alignment = max(alignment, page_alignment);
844 
845 			if (vma->page_sizes.sg & I915_GTT_PAGE_SIZE_64K)
846 				size = round_up(size, I915_GTT_PAGE_SIZE_2M);
847 		}
848 
849 		ret = i915_gem_gtt_insert(vma->vm, ww, &vma->node,
850 					  size, alignment, color,
851 					  start, end, flags);
852 		if (ret)
853 			return ret;
854 
855 		GEM_BUG_ON(vma->node.start < start);
856 		GEM_BUG_ON(vma->node.start + vma->node.size > end);
857 	}
858 	GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
859 	GEM_BUG_ON(!i915_gem_valid_gtt_space(vma, color));
860 
861 	list_move_tail(&vma->vm_link, &vma->vm->bound_list);
862 
863 	return 0;
864 }
865 
866 static void
867 i915_vma_detach(struct i915_vma *vma)
868 {
869 	GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
870 	GEM_BUG_ON(i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND));
871 
872 	/*
873 	 * And finally now the object is completely decoupled from this
874 	 * vma, we can drop its hold on the backing storage and allow
875 	 * it to be reaped by the shrinker.
876 	 */
877 	list_move_tail(&vma->vm_link, &vma->vm->unbound_list);
878 }
879 
880 static bool try_qad_pin(struct i915_vma *vma, unsigned int flags)
881 {
882 	unsigned int bound;
883 
884 	bound = atomic_read(&vma->flags);
885 
886 	if (flags & PIN_VALIDATE) {
887 		flags &= I915_VMA_BIND_MASK;
888 
889 		return (flags & bound) == flags;
890 	}
891 
892 	/* with the lock mandatory for unbind, we don't race here */
893 	flags &= I915_VMA_BIND_MASK;
894 	do {
895 		if (unlikely(flags & ~bound))
896 			return false;
897 
898 		if (unlikely(bound & (I915_VMA_OVERFLOW | I915_VMA_ERROR)))
899 			return false;
900 
901 		GEM_BUG_ON(((bound + 1) & I915_VMA_PIN_MASK) == 0);
902 	} while (!atomic_try_cmpxchg(&vma->flags, &bound, bound + 1));
903 
904 	return true;
905 }
906 
907 static struct scatterlist *
908 rotate_pages(struct drm_i915_gem_object *obj, unsigned int offset,
909 	     unsigned int width, unsigned int height,
910 	     unsigned int src_stride, unsigned int dst_stride,
911 	     struct sg_table *st, struct scatterlist *sg)
912 {
913 	unsigned int column, row;
914 	unsigned int src_idx;
915 
916 	for (column = 0; column < width; column++) {
917 		unsigned int left;
918 
919 		src_idx = src_stride * (height - 1) + column + offset;
920 		for (row = 0; row < height; row++) {
921 			st->nents++;
922 			/*
923 			 * We don't need the pages, but need to initialize
924 			 * the entries so the sg list can be happily traversed.
925 			 * The only thing we need are DMA addresses.
926 			 */
927 			sg_set_page(sg, NULL, I915_GTT_PAGE_SIZE, 0);
928 			sg_dma_address(sg) =
929 				i915_gem_object_get_dma_address(obj, src_idx);
930 			sg_dma_len(sg) = I915_GTT_PAGE_SIZE;
931 			sg = sg_next(sg);
932 			src_idx -= src_stride;
933 		}
934 
935 		left = (dst_stride - height) * I915_GTT_PAGE_SIZE;
936 
937 		if (!left)
938 			continue;
939 
940 		st->nents++;
941 
942 		/*
943 		 * The DE ignores the PTEs for the padding tiles, the sg entry
944 		 * here is just a conenience to indicate how many padding PTEs
945 		 * to insert at this spot.
946 		 */
947 		sg_set_page(sg, NULL, left, 0);
948 		sg_dma_address(sg) = 0;
949 		sg_dma_len(sg) = left;
950 		sg = sg_next(sg);
951 	}
952 
953 	return sg;
954 }
955 
956 static noinline struct sg_table *
957 intel_rotate_pages(struct intel_rotation_info *rot_info,
958 		   struct drm_i915_gem_object *obj)
959 {
960 	unsigned int size = intel_rotation_info_size(rot_info);
961 	struct drm_i915_private *i915 = to_i915(obj->base.dev);
962 	struct sg_table *st;
963 	struct scatterlist *sg;
964 	int ret = -ENOMEM;
965 	int i;
966 
967 	/* Allocate target SG list. */
968 	st = kmalloc(sizeof(*st), GFP_KERNEL);
969 	if (!st)
970 		goto err_st_alloc;
971 
972 	ret = sg_alloc_table(st, size, GFP_KERNEL);
973 	if (ret)
974 		goto err_sg_alloc;
975 
976 	st->nents = 0;
977 	sg = st->sgl;
978 
979 	for (i = 0 ; i < ARRAY_SIZE(rot_info->plane); i++)
980 		sg = rotate_pages(obj, rot_info->plane[i].offset,
981 				  rot_info->plane[i].width, rot_info->plane[i].height,
982 				  rot_info->plane[i].src_stride,
983 				  rot_info->plane[i].dst_stride,
984 				  st, sg);
985 
986 	return st;
987 
988 err_sg_alloc:
989 	kfree(st);
990 err_st_alloc:
991 
992 	drm_dbg(&i915->drm, "Failed to create rotated mapping for object size %zu! (%ux%u tiles, %u pages)\n",
993 		obj->base.size, rot_info->plane[0].width,
994 		rot_info->plane[0].height, size);
995 
996 	return ERR_PTR(ret);
997 }
998 
999 static struct scatterlist *
1000 add_padding_pages(unsigned int count,
1001 		  struct sg_table *st, struct scatterlist *sg)
1002 {
1003 	st->nents++;
1004 
1005 	/*
1006 	 * The DE ignores the PTEs for the padding tiles, the sg entry
1007 	 * here is just a convenience to indicate how many padding PTEs
1008 	 * to insert at this spot.
1009 	 */
1010 	sg_set_page(sg, NULL, count * I915_GTT_PAGE_SIZE, 0);
1011 	sg_dma_address(sg) = 0;
1012 	sg_dma_len(sg) = count * I915_GTT_PAGE_SIZE;
1013 	sg = sg_next(sg);
1014 
1015 	return sg;
1016 }
1017 
1018 static struct scatterlist *
1019 remap_tiled_color_plane_pages(struct drm_i915_gem_object *obj,
1020 			      unsigned int offset, unsigned int alignment_pad,
1021 			      unsigned int width, unsigned int height,
1022 			      unsigned int src_stride, unsigned int dst_stride,
1023 			      struct sg_table *st, struct scatterlist *sg,
1024 			      unsigned int *gtt_offset)
1025 {
1026 	unsigned int row;
1027 
1028 	if (!width || !height)
1029 		return sg;
1030 
1031 	if (alignment_pad)
1032 		sg = add_padding_pages(alignment_pad, st, sg);
1033 
1034 	for (row = 0; row < height; row++) {
1035 		unsigned int left = width * I915_GTT_PAGE_SIZE;
1036 
1037 		while (left) {
1038 			dma_addr_t addr;
1039 			unsigned int length;
1040 
1041 			/*
1042 			 * We don't need the pages, but need to initialize
1043 			 * the entries so the sg list can be happily traversed.
1044 			 * The only thing we need are DMA addresses.
1045 			 */
1046 
1047 			addr = i915_gem_object_get_dma_address_len(obj, offset, &length);
1048 
1049 			length = min(left, length);
1050 
1051 			st->nents++;
1052 
1053 			sg_set_page(sg, NULL, length, 0);
1054 			sg_dma_address(sg) = addr;
1055 			sg_dma_len(sg) = length;
1056 			sg = sg_next(sg);
1057 
1058 			offset += length / I915_GTT_PAGE_SIZE;
1059 			left -= length;
1060 		}
1061 
1062 		offset += src_stride - width;
1063 
1064 		left = (dst_stride - width) * I915_GTT_PAGE_SIZE;
1065 
1066 		if (!left)
1067 			continue;
1068 
1069 		sg = add_padding_pages(left >> PAGE_SHIFT, st, sg);
1070 	}
1071 
1072 	*gtt_offset += alignment_pad + dst_stride * height;
1073 
1074 	return sg;
1075 }
1076 
1077 static struct scatterlist *
1078 remap_contiguous_pages(struct drm_i915_gem_object *obj,
1079 		       unsigned int obj_offset,
1080 		       unsigned int count,
1081 		       struct sg_table *st, struct scatterlist *sg)
1082 {
1083 	struct scatterlist *iter;
1084 	unsigned int offset;
1085 
1086 	iter = i915_gem_object_get_sg_dma(obj, obj_offset, &offset);
1087 	GEM_BUG_ON(!iter);
1088 
1089 	do {
1090 		unsigned int len;
1091 
1092 		len = min(sg_dma_len(iter) - (offset << PAGE_SHIFT),
1093 			  count << PAGE_SHIFT);
1094 		sg_set_page(sg, NULL, len, 0);
1095 		sg_dma_address(sg) =
1096 			sg_dma_address(iter) + (offset << PAGE_SHIFT);
1097 		sg_dma_len(sg) = len;
1098 
1099 		st->nents++;
1100 		count -= len >> PAGE_SHIFT;
1101 		if (count == 0)
1102 			return sg;
1103 
1104 		sg = __sg_next(sg);
1105 		iter = __sg_next(iter);
1106 		offset = 0;
1107 	} while (1);
1108 }
1109 
1110 static struct scatterlist *
1111 remap_linear_color_plane_pages(struct drm_i915_gem_object *obj,
1112 			       unsigned int obj_offset, unsigned int alignment_pad,
1113 			       unsigned int size,
1114 			       struct sg_table *st, struct scatterlist *sg,
1115 			       unsigned int *gtt_offset)
1116 {
1117 	if (!size)
1118 		return sg;
1119 
1120 	if (alignment_pad)
1121 		sg = add_padding_pages(alignment_pad, st, sg);
1122 
1123 	sg = remap_contiguous_pages(obj, obj_offset, size, st, sg);
1124 	sg = sg_next(sg);
1125 
1126 	*gtt_offset += alignment_pad + size;
1127 
1128 	return sg;
1129 }
1130 
1131 static struct scatterlist *
1132 remap_color_plane_pages(const struct intel_remapped_info *rem_info,
1133 			struct drm_i915_gem_object *obj,
1134 			int color_plane,
1135 			struct sg_table *st, struct scatterlist *sg,
1136 			unsigned int *gtt_offset)
1137 {
1138 	unsigned int alignment_pad = 0;
1139 
1140 	if (rem_info->plane_alignment)
1141 		alignment_pad = ALIGN(*gtt_offset, rem_info->plane_alignment) - *gtt_offset;
1142 
1143 	if (rem_info->plane[color_plane].linear)
1144 		sg = remap_linear_color_plane_pages(obj,
1145 						    rem_info->plane[color_plane].offset,
1146 						    alignment_pad,
1147 						    rem_info->plane[color_plane].size,
1148 						    st, sg,
1149 						    gtt_offset);
1150 
1151 	else
1152 		sg = remap_tiled_color_plane_pages(obj,
1153 						   rem_info->plane[color_plane].offset,
1154 						   alignment_pad,
1155 						   rem_info->plane[color_plane].width,
1156 						   rem_info->plane[color_plane].height,
1157 						   rem_info->plane[color_plane].src_stride,
1158 						   rem_info->plane[color_plane].dst_stride,
1159 						   st, sg,
1160 						   gtt_offset);
1161 
1162 	return sg;
1163 }
1164 
1165 static noinline struct sg_table *
1166 intel_remap_pages(struct intel_remapped_info *rem_info,
1167 		  struct drm_i915_gem_object *obj)
1168 {
1169 	unsigned int size = intel_remapped_info_size(rem_info);
1170 	struct drm_i915_private *i915 = to_i915(obj->base.dev);
1171 	struct sg_table *st;
1172 	struct scatterlist *sg;
1173 	unsigned int gtt_offset = 0;
1174 	int ret = -ENOMEM;
1175 	int i;
1176 
1177 	/* Allocate target SG list. */
1178 	st = kmalloc(sizeof(*st), GFP_KERNEL);
1179 	if (!st)
1180 		goto err_st_alloc;
1181 
1182 	ret = sg_alloc_table(st, size, GFP_KERNEL);
1183 	if (ret)
1184 		goto err_sg_alloc;
1185 
1186 	st->nents = 0;
1187 	sg = st->sgl;
1188 
1189 	for (i = 0 ; i < ARRAY_SIZE(rem_info->plane); i++)
1190 		sg = remap_color_plane_pages(rem_info, obj, i, st, sg, &gtt_offset);
1191 
1192 	i915_sg_trim(st);
1193 
1194 	return st;
1195 
1196 err_sg_alloc:
1197 	kfree(st);
1198 err_st_alloc:
1199 
1200 	drm_dbg(&i915->drm, "Failed to create remapped mapping for object size %zu! (%ux%u tiles, %u pages)\n",
1201 		obj->base.size, rem_info->plane[0].width,
1202 		rem_info->plane[0].height, size);
1203 
1204 	return ERR_PTR(ret);
1205 }
1206 
1207 static noinline struct sg_table *
1208 intel_partial_pages(const struct i915_ggtt_view *view,
1209 		    struct drm_i915_gem_object *obj)
1210 {
1211 	struct sg_table *st;
1212 	struct scatterlist *sg;
1213 	unsigned int count = view->partial.size;
1214 	int ret = -ENOMEM;
1215 
1216 	st = kmalloc(sizeof(*st), GFP_KERNEL);
1217 	if (!st)
1218 		goto err_st_alloc;
1219 
1220 	ret = sg_alloc_table(st, count, GFP_KERNEL);
1221 	if (ret)
1222 		goto err_sg_alloc;
1223 
1224 	st->nents = 0;
1225 
1226 	sg = remap_contiguous_pages(obj, view->partial.offset, count, st, st->sgl);
1227 
1228 	sg_mark_end(sg);
1229 	i915_sg_trim(st); /* Drop any unused tail entries. */
1230 
1231 	return st;
1232 
1233 err_sg_alloc:
1234 	kfree(st);
1235 err_st_alloc:
1236 	return ERR_PTR(ret);
1237 }
1238 
1239 static int
1240 __i915_vma_get_pages(struct i915_vma *vma)
1241 {
1242 	struct sg_table *pages;
1243 
1244 	/*
1245 	 * The vma->pages are only valid within the lifespan of the borrowed
1246 	 * obj->mm.pages. When the obj->mm.pages sg_table is regenerated, so
1247 	 * must be the vma->pages. A simple rule is that vma->pages must only
1248 	 * be accessed when the obj->mm.pages are pinned.
1249 	 */
1250 	GEM_BUG_ON(!i915_gem_object_has_pinned_pages(vma->obj));
1251 
1252 	switch (vma->ggtt_view.type) {
1253 	default:
1254 		GEM_BUG_ON(vma->ggtt_view.type);
1255 		fallthrough;
1256 	case I915_GGTT_VIEW_NORMAL:
1257 		pages = vma->obj->mm.pages;
1258 		break;
1259 
1260 	case I915_GGTT_VIEW_ROTATED:
1261 		pages =
1262 			intel_rotate_pages(&vma->ggtt_view.rotated, vma->obj);
1263 		break;
1264 
1265 	case I915_GGTT_VIEW_REMAPPED:
1266 		pages =
1267 			intel_remap_pages(&vma->ggtt_view.remapped, vma->obj);
1268 		break;
1269 
1270 	case I915_GGTT_VIEW_PARTIAL:
1271 		pages = intel_partial_pages(&vma->ggtt_view, vma->obj);
1272 		break;
1273 	}
1274 
1275 	if (IS_ERR(pages)) {
1276 		drm_err(&vma->vm->i915->drm,
1277 			"Failed to get pages for VMA view type %u (%ld)!\n",
1278 			vma->ggtt_view.type, PTR_ERR(pages));
1279 		return PTR_ERR(pages);
1280 	}
1281 
1282 	vma->pages = pages;
1283 
1284 	return 0;
1285 }
1286 
1287 I915_SELFTEST_EXPORT int i915_vma_get_pages(struct i915_vma *vma)
1288 {
1289 	int err;
1290 
1291 	if (atomic_add_unless(&vma->pages_count, 1, 0))
1292 		return 0;
1293 
1294 	err = i915_gem_object_pin_pages(vma->obj);
1295 	if (err)
1296 		return err;
1297 
1298 	err = __i915_vma_get_pages(vma);
1299 	if (err)
1300 		goto err_unpin;
1301 
1302 	vma->page_sizes = vma->obj->mm.page_sizes;
1303 	atomic_inc(&vma->pages_count);
1304 
1305 	return 0;
1306 
1307 err_unpin:
1308 	__i915_gem_object_unpin_pages(vma->obj);
1309 
1310 	return err;
1311 }
1312 
1313 static void __vma_put_pages(struct i915_vma *vma, unsigned int count)
1314 {
1315 	/* We allocate under vma_get_pages, so beware the shrinker */
1316 	GEM_BUG_ON(atomic_read(&vma->pages_count) < count);
1317 
1318 	if (atomic_sub_return(count, &vma->pages_count) == 0) {
1319 		if (vma->pages != vma->obj->mm.pages) {
1320 			sg_free_table(vma->pages);
1321 			kfree(vma->pages);
1322 		}
1323 		vma->pages = NULL;
1324 
1325 		i915_gem_object_unpin_pages(vma->obj);
1326 	}
1327 }
1328 
1329 I915_SELFTEST_EXPORT void i915_vma_put_pages(struct i915_vma *vma)
1330 {
1331 	if (atomic_add_unless(&vma->pages_count, -1, 1))
1332 		return;
1333 
1334 	__vma_put_pages(vma, 1);
1335 }
1336 
1337 static void vma_unbind_pages(struct i915_vma *vma)
1338 {
1339 	unsigned int count;
1340 
1341 	lockdep_assert_held(&vma->vm->mutex);
1342 
1343 	/* The upper portion of pages_count is the number of bindings */
1344 	count = atomic_read(&vma->pages_count);
1345 	count >>= I915_VMA_PAGES_BIAS;
1346 	GEM_BUG_ON(!count);
1347 
1348 	__vma_put_pages(vma, count | count << I915_VMA_PAGES_BIAS);
1349 }
1350 
1351 int i915_vma_pin_ww(struct i915_vma *vma, struct i915_gem_ww_ctx *ww,
1352 		    u64 size, u64 alignment, u64 flags)
1353 {
1354 	struct i915_vma_work *work = NULL;
1355 	struct dma_fence *moving = NULL;
1356 	struct i915_vma_resource *vma_res = NULL;
1357 	intel_wakeref_t wakeref = 0;
1358 	unsigned int bound;
1359 	int err;
1360 
1361 	assert_vma_held(vma);
1362 	GEM_BUG_ON(!ww);
1363 
1364 	BUILD_BUG_ON(PIN_GLOBAL != I915_VMA_GLOBAL_BIND);
1365 	BUILD_BUG_ON(PIN_USER != I915_VMA_LOCAL_BIND);
1366 
1367 	GEM_BUG_ON(!(flags & (PIN_USER | PIN_GLOBAL)));
1368 
1369 	/* First try and grab the pin without rebinding the vma */
1370 	if (try_qad_pin(vma, flags))
1371 		return 0;
1372 
1373 	err = i915_vma_get_pages(vma);
1374 	if (err)
1375 		return err;
1376 
1377 	if (flags & PIN_GLOBAL)
1378 		wakeref = intel_runtime_pm_get(&vma->vm->i915->runtime_pm);
1379 
1380 	if (flags & vma->vm->bind_async_flags) {
1381 		/* lock VM */
1382 		err = i915_vm_lock_objects(vma->vm, ww);
1383 		if (err)
1384 			goto err_rpm;
1385 
1386 		work = i915_vma_work();
1387 		if (!work) {
1388 			err = -ENOMEM;
1389 			goto err_rpm;
1390 		}
1391 
1392 		work->vm = vma->vm;
1393 
1394 		err = i915_gem_object_get_moving_fence(vma->obj, &moving);
1395 		if (err)
1396 			goto err_rpm;
1397 
1398 		dma_fence_work_chain(&work->base, moving);
1399 
1400 		/* Allocate enough page directories to used PTE */
1401 		if (vma->vm->allocate_va_range) {
1402 			err = i915_vm_alloc_pt_stash(vma->vm,
1403 						     &work->stash,
1404 						     vma->size);
1405 			if (err)
1406 				goto err_fence;
1407 
1408 			err = i915_vm_map_pt_stash(vma->vm, &work->stash);
1409 			if (err)
1410 				goto err_fence;
1411 		}
1412 	}
1413 
1414 	vma_res = i915_vma_resource_alloc();
1415 	if (IS_ERR(vma_res)) {
1416 		err = PTR_ERR(vma_res);
1417 		goto err_fence;
1418 	}
1419 
1420 	/*
1421 	 * Differentiate between user/kernel vma inside the aliasing-ppgtt.
1422 	 *
1423 	 * We conflate the Global GTT with the user's vma when using the
1424 	 * aliasing-ppgtt, but it is still vitally important to try and
1425 	 * keep the use cases distinct. For example, userptr objects are
1426 	 * not allowed inside the Global GTT as that will cause lock
1427 	 * inversions when we have to evict them the mmu_notifier callbacks -
1428 	 * but they are allowed to be part of the user ppGTT which can never
1429 	 * be mapped. As such we try to give the distinct users of the same
1430 	 * mutex, distinct lockclasses [equivalent to how we keep i915_ggtt
1431 	 * and i915_ppgtt separate].
1432 	 *
1433 	 * NB this may cause us to mask real lock inversions -- while the
1434 	 * code is safe today, lockdep may not be able to spot future
1435 	 * transgressions.
1436 	 */
1437 	err = mutex_lock_interruptible_nested(&vma->vm->mutex,
1438 					      !(flags & PIN_GLOBAL));
1439 	if (err)
1440 		goto err_vma_res;
1441 
1442 	/* No more allocations allowed now we hold vm->mutex */
1443 
1444 	if (unlikely(i915_vma_is_closed(vma))) {
1445 		err = -ENOENT;
1446 		goto err_unlock;
1447 	}
1448 
1449 	bound = atomic_read(&vma->flags);
1450 	if (unlikely(bound & I915_VMA_ERROR)) {
1451 		err = -ENOMEM;
1452 		goto err_unlock;
1453 	}
1454 
1455 	if (unlikely(!((bound + 1) & I915_VMA_PIN_MASK))) {
1456 		err = -EAGAIN; /* pins are meant to be fairly temporary */
1457 		goto err_unlock;
1458 	}
1459 
1460 	if (unlikely(!(flags & ~bound & I915_VMA_BIND_MASK))) {
1461 		if (!(flags & PIN_VALIDATE))
1462 			__i915_vma_pin(vma);
1463 		goto err_unlock;
1464 	}
1465 
1466 	err = i915_active_acquire(&vma->active);
1467 	if (err)
1468 		goto err_unlock;
1469 
1470 	if (!(bound & I915_VMA_BIND_MASK)) {
1471 		err = i915_vma_insert(vma, ww, size, alignment, flags);
1472 		if (err)
1473 			goto err_active;
1474 
1475 		if (i915_is_ggtt(vma->vm))
1476 			__i915_vma_set_map_and_fenceable(vma);
1477 	}
1478 
1479 	GEM_BUG_ON(!vma->pages);
1480 	err = i915_vma_bind(vma,
1481 			    vma->obj->cache_level,
1482 			    flags, work, vma_res);
1483 	vma_res = NULL;
1484 	if (err)
1485 		goto err_remove;
1486 
1487 	/* There should only be at most 2 active bindings (user, global) */
1488 	GEM_BUG_ON(bound + I915_VMA_PAGES_ACTIVE < bound);
1489 	atomic_add(I915_VMA_PAGES_ACTIVE, &vma->pages_count);
1490 	list_move_tail(&vma->vm_link, &vma->vm->bound_list);
1491 
1492 	if (!(flags & PIN_VALIDATE)) {
1493 		__i915_vma_pin(vma);
1494 		GEM_BUG_ON(!i915_vma_is_pinned(vma));
1495 	}
1496 	GEM_BUG_ON(!i915_vma_is_bound(vma, flags));
1497 	GEM_BUG_ON(i915_vma_misplaced(vma, size, alignment, flags));
1498 
1499 err_remove:
1500 	if (!i915_vma_is_bound(vma, I915_VMA_BIND_MASK)) {
1501 		i915_vma_detach(vma);
1502 		drm_mm_remove_node(&vma->node);
1503 	}
1504 err_active:
1505 	i915_active_release(&vma->active);
1506 err_unlock:
1507 	mutex_unlock(&vma->vm->mutex);
1508 err_vma_res:
1509 	i915_vma_resource_free(vma_res);
1510 err_fence:
1511 	if (work)
1512 		dma_fence_work_commit_imm(&work->base);
1513 err_rpm:
1514 	if (wakeref)
1515 		intel_runtime_pm_put(&vma->vm->i915->runtime_pm, wakeref);
1516 
1517 	if (moving)
1518 		dma_fence_put(moving);
1519 
1520 	i915_vma_put_pages(vma);
1521 	return err;
1522 }
1523 
1524 static void flush_idle_contexts(struct intel_gt *gt)
1525 {
1526 	struct intel_engine_cs *engine;
1527 	enum intel_engine_id id;
1528 
1529 	for_each_engine(engine, gt, id)
1530 		intel_engine_flush_barriers(engine);
1531 
1532 	intel_gt_wait_for_idle(gt, MAX_SCHEDULE_TIMEOUT);
1533 }
1534 
1535 static int __i915_ggtt_pin(struct i915_vma *vma, struct i915_gem_ww_ctx *ww,
1536 			   u32 align, unsigned int flags)
1537 {
1538 	struct i915_address_space *vm = vma->vm;
1539 	int err;
1540 
1541 	do {
1542 		err = i915_vma_pin_ww(vma, ww, 0, align, flags | PIN_GLOBAL);
1543 
1544 		if (err != -ENOSPC) {
1545 			if (!err) {
1546 				err = i915_vma_wait_for_bind(vma);
1547 				if (err)
1548 					i915_vma_unpin(vma);
1549 			}
1550 			return err;
1551 		}
1552 
1553 		/* Unlike i915_vma_pin, we don't take no for an answer! */
1554 		flush_idle_contexts(vm->gt);
1555 		if (mutex_lock_interruptible(&vm->mutex) == 0) {
1556 			/*
1557 			 * We pass NULL ww here, as we don't want to unbind
1558 			 * locked objects when called from execbuf when pinning
1559 			 * is removed. This would probably regress badly.
1560 			 */
1561 			i915_gem_evict_vm(vm, NULL);
1562 			mutex_unlock(&vm->mutex);
1563 		}
1564 	} while (1);
1565 }
1566 
1567 int i915_ggtt_pin(struct i915_vma *vma, struct i915_gem_ww_ctx *ww,
1568 		  u32 align, unsigned int flags)
1569 {
1570 	struct i915_gem_ww_ctx _ww;
1571 	int err;
1572 
1573 	GEM_BUG_ON(!i915_vma_is_ggtt(vma));
1574 
1575 	if (ww)
1576 		return __i915_ggtt_pin(vma, ww, align, flags);
1577 
1578 	lockdep_assert_not_held(&vma->obj->base.resv->lock.base);
1579 
1580 	for_i915_gem_ww(&_ww, err, true) {
1581 		err = i915_gem_object_lock(vma->obj, &_ww);
1582 		if (!err)
1583 			err = __i915_ggtt_pin(vma, &_ww, align, flags);
1584 	}
1585 
1586 	return err;
1587 }
1588 
1589 static void __vma_close(struct i915_vma *vma, struct intel_gt *gt)
1590 {
1591 	/*
1592 	 * We defer actually closing, unbinding and destroying the VMA until
1593 	 * the next idle point, or if the object is freed in the meantime. By
1594 	 * postponing the unbind, we allow for it to be resurrected by the
1595 	 * client, avoiding the work required to rebind the VMA. This is
1596 	 * advantageous for DRI, where the client/server pass objects
1597 	 * between themselves, temporarily opening a local VMA to the
1598 	 * object, and then closing it again. The same object is then reused
1599 	 * on the next frame (or two, depending on the depth of the swap queue)
1600 	 * causing us to rebind the VMA once more. This ends up being a lot
1601 	 * of wasted work for the steady state.
1602 	 */
1603 	GEM_BUG_ON(i915_vma_is_closed(vma));
1604 	list_add(&vma->closed_link, &gt->closed_vma);
1605 }
1606 
1607 void i915_vma_close(struct i915_vma *vma)
1608 {
1609 	struct intel_gt *gt = vma->vm->gt;
1610 	unsigned long flags;
1611 
1612 	if (i915_vma_is_ggtt(vma))
1613 		return;
1614 
1615 	GEM_BUG_ON(!atomic_read(&vma->open_count));
1616 	if (atomic_dec_and_lock_irqsave(&vma->open_count,
1617 					&gt->closed_lock,
1618 					flags)) {
1619 		__vma_close(vma, gt);
1620 		spin_unlock_irqrestore(&gt->closed_lock, flags);
1621 	}
1622 }
1623 
1624 static void __i915_vma_remove_closed(struct i915_vma *vma)
1625 {
1626 	list_del_init(&vma->closed_link);
1627 }
1628 
1629 void i915_vma_reopen(struct i915_vma *vma)
1630 {
1631 	struct intel_gt *gt = vma->vm->gt;
1632 
1633 	spin_lock_irq(&gt->closed_lock);
1634 	if (i915_vma_is_closed(vma))
1635 		__i915_vma_remove_closed(vma);
1636 	spin_unlock_irq(&gt->closed_lock);
1637 }
1638 
1639 static void force_unbind(struct i915_vma *vma)
1640 {
1641 	if (!drm_mm_node_allocated(&vma->node))
1642 		return;
1643 
1644 	atomic_and(~I915_VMA_PIN_MASK, &vma->flags);
1645 	WARN_ON(__i915_vma_unbind(vma));
1646 	GEM_BUG_ON(drm_mm_node_allocated(&vma->node));
1647 }
1648 
1649 static void release_references(struct i915_vma *vma, struct intel_gt *gt,
1650 			       bool vm_ddestroy)
1651 {
1652 	struct drm_i915_gem_object *obj = vma->obj;
1653 
1654 	GEM_BUG_ON(i915_vma_is_active(vma));
1655 
1656 	spin_lock(&obj->vma.lock);
1657 	list_del(&vma->obj_link);
1658 	if (!RB_EMPTY_NODE(&vma->obj_node))
1659 		rb_erase(&vma->obj_node, &obj->vma.tree);
1660 
1661 	spin_unlock(&obj->vma.lock);
1662 
1663 	spin_lock_irq(&gt->closed_lock);
1664 	__i915_vma_remove_closed(vma);
1665 	spin_unlock_irq(&gt->closed_lock);
1666 
1667 	if (vm_ddestroy)
1668 		i915_vm_resv_put(vma->vm);
1669 
1670 	i915_active_fini(&vma->active);
1671 	GEM_WARN_ON(vma->resource);
1672 	i915_vma_free(vma);
1673 }
1674 
1675 /**
1676  * i915_vma_destroy_locked - Remove all weak reference to the vma and put
1677  * the initial reference.
1678  *
1679  * This function should be called when it's decided the vma isn't needed
1680  * anymore. The caller must assure that it doesn't race with another lookup
1681  * plus destroy, typically by taking an appropriate reference.
1682  *
1683  * Current callsites are
1684  * - __i915_gem_object_pages_fini()
1685  * - __i915_vm_close() - Blocks the above function by taking a reference on
1686  * the object.
1687  * - __i915_vma_parked() - Blocks the above functions by taking a reference
1688  * on the vm and a reference on the object. Also takes the object lock so
1689  * destruction from __i915_vma_parked() can be blocked by holding the
1690  * object lock. Since the object lock is only allowed from within i915 with
1691  * an object refcount, holding the object lock also implicitly blocks the
1692  * vma freeing from __i915_gem_object_pages_fini().
1693  *
1694  * Because of locks taken during destruction, a vma is also guaranteed to
1695  * stay alive while the following locks are held if it was looked up while
1696  * holding one of the locks:
1697  * - vm->mutex
1698  * - obj->vma.lock
1699  * - gt->closed_lock
1700  */
1701 void i915_vma_destroy_locked(struct i915_vma *vma)
1702 {
1703 	lockdep_assert_held(&vma->vm->mutex);
1704 
1705 	force_unbind(vma);
1706 	list_del_init(&vma->vm_link);
1707 	release_references(vma, vma->vm->gt, false);
1708 }
1709 
1710 void i915_vma_destroy(struct i915_vma *vma)
1711 {
1712 	struct intel_gt *gt;
1713 	bool vm_ddestroy;
1714 
1715 	mutex_lock(&vma->vm->mutex);
1716 	force_unbind(vma);
1717 	list_del_init(&vma->vm_link);
1718 	vm_ddestroy = vma->vm_ddestroy;
1719 	vma->vm_ddestroy = false;
1720 
1721 	/* vma->vm may be freed when releasing vma->vm->mutex. */
1722 	gt = vma->vm->gt;
1723 	mutex_unlock(&vma->vm->mutex);
1724 	release_references(vma, gt, vm_ddestroy);
1725 }
1726 
1727 void i915_vma_parked(struct intel_gt *gt)
1728 {
1729 	struct i915_vma *vma, *next;
1730 	LIST_HEAD(closed);
1731 
1732 	spin_lock_irq(&gt->closed_lock);
1733 	list_for_each_entry_safe(vma, next, &gt->closed_vma, closed_link) {
1734 		struct drm_i915_gem_object *obj = vma->obj;
1735 		struct i915_address_space *vm = vma->vm;
1736 
1737 		/* XXX All to avoid keeping a reference on i915_vma itself */
1738 
1739 		if (!kref_get_unless_zero(&obj->base.refcount))
1740 			continue;
1741 
1742 		if (!i915_vm_tryget(vm)) {
1743 			i915_gem_object_put(obj);
1744 			continue;
1745 		}
1746 
1747 		list_move(&vma->closed_link, &closed);
1748 	}
1749 	spin_unlock_irq(&gt->closed_lock);
1750 
1751 	/* As the GT is held idle, no vma can be reopened as we destroy them */
1752 	list_for_each_entry_safe(vma, next, &closed, closed_link) {
1753 		struct drm_i915_gem_object *obj = vma->obj;
1754 		struct i915_address_space *vm = vma->vm;
1755 
1756 		if (i915_gem_object_trylock(obj, NULL)) {
1757 			INIT_LIST_HEAD(&vma->closed_link);
1758 			i915_vma_destroy(vma);
1759 			i915_gem_object_unlock(obj);
1760 		} else {
1761 			/* back you go.. */
1762 			spin_lock_irq(&gt->closed_lock);
1763 			list_add(&vma->closed_link, &gt->closed_vma);
1764 			spin_unlock_irq(&gt->closed_lock);
1765 		}
1766 
1767 		i915_gem_object_put(obj);
1768 		i915_vm_put(vm);
1769 	}
1770 }
1771 
1772 static void __i915_vma_iounmap(struct i915_vma *vma)
1773 {
1774 	GEM_BUG_ON(i915_vma_is_pinned(vma));
1775 
1776 	if (vma->iomap == NULL)
1777 		return;
1778 
1779 	if (page_unmask_bits(vma->iomap))
1780 		__i915_gem_object_release_map(vma->obj);
1781 	else
1782 		io_mapping_unmap(vma->iomap);
1783 	vma->iomap = NULL;
1784 }
1785 
1786 void i915_vma_revoke_mmap(struct i915_vma *vma)
1787 {
1788 	struct drm_vma_offset_node *node;
1789 	u64 vma_offset;
1790 
1791 	if (!i915_vma_has_userfault(vma))
1792 		return;
1793 
1794 	GEM_BUG_ON(!i915_vma_is_map_and_fenceable(vma));
1795 	GEM_BUG_ON(!vma->obj->userfault_count);
1796 
1797 	node = &vma->mmo->vma_node;
1798 	vma_offset = vma->ggtt_view.partial.offset << PAGE_SHIFT;
1799 	unmap_mapping_range(vma->vm->i915->drm.anon_inode->i_mapping,
1800 			    drm_vma_node_offset_addr(node) + vma_offset,
1801 			    vma->size,
1802 			    1);
1803 
1804 	i915_vma_unset_userfault(vma);
1805 	if (!--vma->obj->userfault_count)
1806 		list_del(&vma->obj->userfault_link);
1807 }
1808 
1809 static int
1810 __i915_request_await_bind(struct i915_request *rq, struct i915_vma *vma)
1811 {
1812 	return __i915_request_await_exclusive(rq, &vma->active);
1813 }
1814 
1815 static int __i915_vma_move_to_active(struct i915_vma *vma, struct i915_request *rq)
1816 {
1817 	int err;
1818 
1819 	/* Wait for the vma to be bound before we start! */
1820 	err = __i915_request_await_bind(rq, vma);
1821 	if (err)
1822 		return err;
1823 
1824 	return i915_active_add_request(&vma->active, rq);
1825 }
1826 
1827 int _i915_vma_move_to_active(struct i915_vma *vma,
1828 			     struct i915_request *rq,
1829 			     struct dma_fence *fence,
1830 			     unsigned int flags)
1831 {
1832 	struct drm_i915_gem_object *obj = vma->obj;
1833 	int err;
1834 
1835 	assert_object_held(obj);
1836 
1837 	GEM_BUG_ON(!vma->pages);
1838 
1839 	err = __i915_vma_move_to_active(vma, rq);
1840 	if (unlikely(err))
1841 		return err;
1842 
1843 	/*
1844 	 * Reserve fences slot early to prevent an allocation after preparing
1845 	 * the workload and associating fences with dma_resv.
1846 	 */
1847 	if (fence && !(flags & __EXEC_OBJECT_NO_RESERVE)) {
1848 		struct dma_fence *curr;
1849 		int idx;
1850 
1851 		dma_fence_array_for_each(curr, idx, fence)
1852 			;
1853 		err = dma_resv_reserve_fences(vma->obj->base.resv, idx);
1854 		if (unlikely(err))
1855 			return err;
1856 	}
1857 
1858 	if (flags & EXEC_OBJECT_WRITE) {
1859 		struct intel_frontbuffer *front;
1860 
1861 		front = __intel_frontbuffer_get(obj);
1862 		if (unlikely(front)) {
1863 			if (intel_frontbuffer_invalidate(front, ORIGIN_CS))
1864 				i915_active_add_request(&front->write, rq);
1865 			intel_frontbuffer_put(front);
1866 		}
1867 	}
1868 
1869 	if (fence) {
1870 		struct dma_fence *curr;
1871 		enum dma_resv_usage usage;
1872 		int idx;
1873 
1874 		obj->read_domains = 0;
1875 		if (flags & EXEC_OBJECT_WRITE) {
1876 			usage = DMA_RESV_USAGE_WRITE;
1877 			obj->write_domain = I915_GEM_DOMAIN_RENDER;
1878 		} else {
1879 			usage = DMA_RESV_USAGE_READ;
1880 		}
1881 
1882 		dma_fence_array_for_each(curr, idx, fence)
1883 			dma_resv_add_fence(vma->obj->base.resv, curr, usage);
1884 	}
1885 
1886 	if (flags & EXEC_OBJECT_NEEDS_FENCE && vma->fence)
1887 		i915_active_add_request(&vma->fence->active, rq);
1888 
1889 	obj->read_domains |= I915_GEM_GPU_DOMAINS;
1890 	obj->mm.dirty = true;
1891 
1892 	GEM_BUG_ON(!i915_vma_is_active(vma));
1893 	return 0;
1894 }
1895 
1896 struct dma_fence *__i915_vma_evict(struct i915_vma *vma, bool async)
1897 {
1898 	struct i915_vma_resource *vma_res = vma->resource;
1899 	struct dma_fence *unbind_fence;
1900 
1901 	GEM_BUG_ON(i915_vma_is_pinned(vma));
1902 	assert_vma_held_evict(vma);
1903 
1904 	if (i915_vma_is_map_and_fenceable(vma)) {
1905 		/* Force a pagefault for domain tracking on next user access */
1906 		i915_vma_revoke_mmap(vma);
1907 
1908 		/*
1909 		 * Check that we have flushed all writes through the GGTT
1910 		 * before the unbind, other due to non-strict nature of those
1911 		 * indirect writes they may end up referencing the GGTT PTE
1912 		 * after the unbind.
1913 		 *
1914 		 * Note that we may be concurrently poking at the GGTT_WRITE
1915 		 * bit from set-domain, as we mark all GGTT vma associated
1916 		 * with an object. We know this is for another vma, as we
1917 		 * are currently unbinding this one -- so if this vma will be
1918 		 * reused, it will be refaulted and have its dirty bit set
1919 		 * before the next write.
1920 		 */
1921 		i915_vma_flush_writes(vma);
1922 
1923 		/* release the fence reg _after_ flushing */
1924 		i915_vma_revoke_fence(vma);
1925 
1926 		clear_bit(I915_VMA_CAN_FENCE_BIT, __i915_vma_flags(vma));
1927 	}
1928 
1929 	__i915_vma_iounmap(vma);
1930 
1931 	GEM_BUG_ON(vma->fence);
1932 	GEM_BUG_ON(i915_vma_has_userfault(vma));
1933 
1934 	/* Object backend must be async capable. */
1935 	GEM_WARN_ON(async && !vma->resource->bi.pages_rsgt);
1936 
1937 	/* If vm is not open, unbind is a nop. */
1938 	vma_res->needs_wakeref = i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND) &&
1939 		kref_read(&vma->vm->ref);
1940 	vma_res->skip_pte_rewrite = !kref_read(&vma->vm->ref) ||
1941 		vma->vm->skip_pte_rewrite;
1942 	trace_i915_vma_unbind(vma);
1943 
1944 	unbind_fence = i915_vma_resource_unbind(vma_res);
1945 	vma->resource = NULL;
1946 
1947 	atomic_and(~(I915_VMA_BIND_MASK | I915_VMA_ERROR | I915_VMA_GGTT_WRITE),
1948 		   &vma->flags);
1949 
1950 	i915_vma_detach(vma);
1951 
1952 	if (!async && unbind_fence) {
1953 		dma_fence_wait(unbind_fence, false);
1954 		dma_fence_put(unbind_fence);
1955 		unbind_fence = NULL;
1956 	}
1957 
1958 	/*
1959 	 * Binding itself may not have completed until the unbind fence signals,
1960 	 * so don't drop the pages until that happens, unless the resource is
1961 	 * async_capable.
1962 	 */
1963 
1964 	vma_unbind_pages(vma);
1965 	return unbind_fence;
1966 }
1967 
1968 int __i915_vma_unbind(struct i915_vma *vma)
1969 {
1970 	int ret;
1971 
1972 	lockdep_assert_held(&vma->vm->mutex);
1973 	assert_vma_held_evict(vma);
1974 
1975 	if (!drm_mm_node_allocated(&vma->node))
1976 		return 0;
1977 
1978 	if (i915_vma_is_pinned(vma)) {
1979 		vma_print_allocator(vma, "is pinned");
1980 		return -EAGAIN;
1981 	}
1982 
1983 	/*
1984 	 * After confirming that no one else is pinning this vma, wait for
1985 	 * any laggards who may have crept in during the wait (through
1986 	 * a residual pin skipping the vm->mutex) to complete.
1987 	 */
1988 	ret = i915_vma_sync(vma);
1989 	if (ret)
1990 		return ret;
1991 
1992 	GEM_BUG_ON(i915_vma_is_active(vma));
1993 	__i915_vma_evict(vma, false);
1994 
1995 	drm_mm_remove_node(&vma->node); /* pairs with i915_vma_release() */
1996 	return 0;
1997 }
1998 
1999 static struct dma_fence *__i915_vma_unbind_async(struct i915_vma *vma)
2000 {
2001 	struct dma_fence *fence;
2002 
2003 	lockdep_assert_held(&vma->vm->mutex);
2004 
2005 	if (!drm_mm_node_allocated(&vma->node))
2006 		return NULL;
2007 
2008 	if (i915_vma_is_pinned(vma) ||
2009 	    &vma->obj->mm.rsgt->table != vma->resource->bi.pages)
2010 		return ERR_PTR(-EAGAIN);
2011 
2012 	/*
2013 	 * We probably need to replace this with awaiting the fences of the
2014 	 * object's dma_resv when the vma active goes away. When doing that
2015 	 * we need to be careful to not add the vma_resource unbind fence
2016 	 * immediately to the object's dma_resv, because then unbinding
2017 	 * the next vma from the object, in case there are many, will
2018 	 * actually await the unbinding of the previous vmas, which is
2019 	 * undesirable.
2020 	 */
2021 	if (i915_sw_fence_await_active(&vma->resource->chain, &vma->active,
2022 				       I915_ACTIVE_AWAIT_EXCL |
2023 				       I915_ACTIVE_AWAIT_ACTIVE) < 0) {
2024 		return ERR_PTR(-EBUSY);
2025 	}
2026 
2027 	fence = __i915_vma_evict(vma, true);
2028 
2029 	drm_mm_remove_node(&vma->node); /* pairs with i915_vma_release() */
2030 
2031 	return fence;
2032 }
2033 
2034 int i915_vma_unbind(struct i915_vma *vma)
2035 {
2036 	struct i915_address_space *vm = vma->vm;
2037 	intel_wakeref_t wakeref = 0;
2038 	int err;
2039 
2040 	assert_object_held_shared(vma->obj);
2041 
2042 	/* Optimistic wait before taking the mutex */
2043 	err = i915_vma_sync(vma);
2044 	if (err)
2045 		return err;
2046 
2047 	if (!drm_mm_node_allocated(&vma->node))
2048 		return 0;
2049 
2050 	if (i915_vma_is_pinned(vma)) {
2051 		vma_print_allocator(vma, "is pinned");
2052 		return -EAGAIN;
2053 	}
2054 
2055 	if (i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND))
2056 		/* XXX not always required: nop_clear_range */
2057 		wakeref = intel_runtime_pm_get(&vm->i915->runtime_pm);
2058 
2059 	err = mutex_lock_interruptible_nested(&vma->vm->mutex, !wakeref);
2060 	if (err)
2061 		goto out_rpm;
2062 
2063 	err = __i915_vma_unbind(vma);
2064 	mutex_unlock(&vm->mutex);
2065 
2066 out_rpm:
2067 	if (wakeref)
2068 		intel_runtime_pm_put(&vm->i915->runtime_pm, wakeref);
2069 	return err;
2070 }
2071 
2072 int i915_vma_unbind_async(struct i915_vma *vma, bool trylock_vm)
2073 {
2074 	struct drm_i915_gem_object *obj = vma->obj;
2075 	struct i915_address_space *vm = vma->vm;
2076 	intel_wakeref_t wakeref = 0;
2077 	struct dma_fence *fence;
2078 	int err;
2079 
2080 	/*
2081 	 * We need the dma-resv lock since we add the
2082 	 * unbind fence to the dma-resv object.
2083 	 */
2084 	assert_object_held(obj);
2085 
2086 	if (!drm_mm_node_allocated(&vma->node))
2087 		return 0;
2088 
2089 	if (i915_vma_is_pinned(vma)) {
2090 		vma_print_allocator(vma, "is pinned");
2091 		return -EAGAIN;
2092 	}
2093 
2094 	if (!obj->mm.rsgt)
2095 		return -EBUSY;
2096 
2097 	err = dma_resv_reserve_fences(obj->base.resv, 1);
2098 	if (err)
2099 		return -EBUSY;
2100 
2101 	/*
2102 	 * It would be great if we could grab this wakeref from the
2103 	 * async unbind work if needed, but we can't because it uses
2104 	 * kmalloc and it's in the dma-fence signalling critical path.
2105 	 */
2106 	if (i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND))
2107 		wakeref = intel_runtime_pm_get(&vm->i915->runtime_pm);
2108 
2109 	if (trylock_vm && !mutex_trylock(&vm->mutex)) {
2110 		err = -EBUSY;
2111 		goto out_rpm;
2112 	} else if (!trylock_vm) {
2113 		err = mutex_lock_interruptible_nested(&vm->mutex, !wakeref);
2114 		if (err)
2115 			goto out_rpm;
2116 	}
2117 
2118 	fence = __i915_vma_unbind_async(vma);
2119 	mutex_unlock(&vm->mutex);
2120 	if (IS_ERR_OR_NULL(fence)) {
2121 		err = PTR_ERR_OR_ZERO(fence);
2122 		goto out_rpm;
2123 	}
2124 
2125 	dma_resv_add_fence(obj->base.resv, fence, DMA_RESV_USAGE_READ);
2126 	dma_fence_put(fence);
2127 
2128 out_rpm:
2129 	if (wakeref)
2130 		intel_runtime_pm_put(&vm->i915->runtime_pm, wakeref);
2131 	return err;
2132 }
2133 
2134 int i915_vma_unbind_unlocked(struct i915_vma *vma)
2135 {
2136 	int err;
2137 
2138 	i915_gem_object_lock(vma->obj, NULL);
2139 	err = i915_vma_unbind(vma);
2140 	i915_gem_object_unlock(vma->obj);
2141 
2142 	return err;
2143 }
2144 
2145 struct i915_vma *i915_vma_make_unshrinkable(struct i915_vma *vma)
2146 {
2147 	i915_gem_object_make_unshrinkable(vma->obj);
2148 	return vma;
2149 }
2150 
2151 void i915_vma_make_shrinkable(struct i915_vma *vma)
2152 {
2153 	i915_gem_object_make_shrinkable(vma->obj);
2154 }
2155 
2156 void i915_vma_make_purgeable(struct i915_vma *vma)
2157 {
2158 	i915_gem_object_make_purgeable(vma->obj);
2159 }
2160 
2161 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
2162 #include "selftests/i915_vma.c"
2163 #endif
2164 
2165 void i915_vma_module_exit(void)
2166 {
2167 	kmem_cache_destroy(slab_vmas);
2168 }
2169 
2170 int __init i915_vma_module_init(void)
2171 {
2172 	slab_vmas = KMEM_CACHE(i915_vma, SLAB_HWCACHE_ALIGN);
2173 	if (!slab_vmas)
2174 		return -ENOMEM;
2175 
2176 	return 0;
2177 }
2178