xref: /openbmc/linux/drivers/gpu/drm/i915/i915_vma.c (revision 759426c7)
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_display.h"
30 #include "display/intel_frontbuffer.h"
31 #include "gem/i915_gem_lmem.h"
32 #include "gem/i915_gem_tiling.h"
33 #include "gt/intel_engine.h"
34 #include "gt/intel_engine_heartbeat.h"
35 #include "gt/intel_gt.h"
36 #include "gt/intel_gt_requests.h"
37 #include "gt/intel_tlb.h"
38 
39 #include "i915_drv.h"
40 #include "i915_gem_evict.h"
41 #include "i915_sw_fence_work.h"
42 #include "i915_trace.h"
43 #include "i915_vma.h"
44 #include "i915_vma_resource.h"
45 
46 static inline void assert_vma_held_evict(const struct i915_vma *vma)
47 {
48 	/*
49 	 * We may be forced to unbind when the vm is dead, to clean it up.
50 	 * This is the only exception to the requirement of the object lock
51 	 * being held.
52 	 */
53 	if (kref_read(&vma->vm->ref))
54 		assert_object_held_shared(vma->obj);
55 }
56 
57 static struct kmem_cache *slab_vmas;
58 
59 static struct i915_vma *i915_vma_alloc(void)
60 {
61 	return kmem_cache_zalloc(slab_vmas, GFP_KERNEL);
62 }
63 
64 static void i915_vma_free(struct i915_vma *vma)
65 {
66 	return kmem_cache_free(slab_vmas, vma);
67 }
68 
69 #if IS_ENABLED(CONFIG_DRM_I915_ERRLOG_GEM) && IS_ENABLED(CONFIG_DRM_DEBUG_MM)
70 
71 #include <linux/stackdepot.h>
72 
73 static void vma_print_allocator(struct i915_vma *vma, const char *reason)
74 {
75 	char buf[512];
76 
77 	if (!vma->node.stack) {
78 		drm_dbg(vma->obj->base.dev,
79 			"vma.node [%08llx + %08llx] %s: unknown owner\n",
80 			vma->node.start, vma->node.size, reason);
81 		return;
82 	}
83 
84 	stack_depot_snprint(vma->node.stack, buf, sizeof(buf), 0);
85 	drm_dbg(vma->obj->base.dev,
86 		"vma.node [%08llx + %08llx] %s: inserted at %s\n",
87 		vma->node.start, vma->node.size, reason, buf);
88 }
89 
90 #else
91 
92 static void vma_print_allocator(struct i915_vma *vma, const char *reason)
93 {
94 }
95 
96 #endif
97 
98 static inline struct i915_vma *active_to_vma(struct i915_active *ref)
99 {
100 	return container_of(ref, typeof(struct i915_vma), active);
101 }
102 
103 static int __i915_vma_active(struct i915_active *ref)
104 {
105 	return i915_vma_tryget(active_to_vma(ref)) ? 0 : -ENOENT;
106 }
107 
108 static void __i915_vma_retire(struct i915_active *ref)
109 {
110 	i915_vma_put(active_to_vma(ref));
111 }
112 
113 static struct i915_vma *
114 vma_create(struct drm_i915_gem_object *obj,
115 	   struct i915_address_space *vm,
116 	   const struct i915_gtt_view *view)
117 {
118 	struct i915_vma *pos = ERR_PTR(-E2BIG);
119 	struct i915_vma *vma;
120 	struct rb_node *rb, **p;
121 	int err;
122 
123 	/* The aliasing_ppgtt should never be used directly! */
124 	GEM_BUG_ON(vm == &vm->gt->ggtt->alias->vm);
125 
126 	vma = i915_vma_alloc();
127 	if (vma == NULL)
128 		return ERR_PTR(-ENOMEM);
129 
130 	vma->ops = &vm->vma_ops;
131 	vma->obj = obj;
132 	vma->size = obj->base.size;
133 	vma->display_alignment = I915_GTT_MIN_ALIGNMENT;
134 
135 	i915_active_init(&vma->active, __i915_vma_active, __i915_vma_retire, 0);
136 
137 	/* Declare ourselves safe for use inside shrinkers */
138 	if (IS_ENABLED(CONFIG_LOCKDEP)) {
139 		fs_reclaim_acquire(GFP_KERNEL);
140 		might_lock(&vma->active.mutex);
141 		fs_reclaim_release(GFP_KERNEL);
142 	}
143 
144 	INIT_LIST_HEAD(&vma->closed_link);
145 	INIT_LIST_HEAD(&vma->obj_link);
146 	RB_CLEAR_NODE(&vma->obj_node);
147 
148 	if (view && view->type != I915_GTT_VIEW_NORMAL) {
149 		vma->gtt_view = *view;
150 		if (view->type == I915_GTT_VIEW_PARTIAL) {
151 			GEM_BUG_ON(range_overflows_t(u64,
152 						     view->partial.offset,
153 						     view->partial.size,
154 						     obj->base.size >> PAGE_SHIFT));
155 			vma->size = view->partial.size;
156 			vma->size <<= PAGE_SHIFT;
157 			GEM_BUG_ON(vma->size > obj->base.size);
158 		} else if (view->type == I915_GTT_VIEW_ROTATED) {
159 			vma->size = intel_rotation_info_size(&view->rotated);
160 			vma->size <<= PAGE_SHIFT;
161 		} else if (view->type == I915_GTT_VIEW_REMAPPED) {
162 			vma->size = intel_remapped_info_size(&view->remapped);
163 			vma->size <<= PAGE_SHIFT;
164 		}
165 	}
166 
167 	if (unlikely(vma->size > vm->total))
168 		goto err_vma;
169 
170 	GEM_BUG_ON(!IS_ALIGNED(vma->size, I915_GTT_PAGE_SIZE));
171 
172 	err = mutex_lock_interruptible(&vm->mutex);
173 	if (err) {
174 		pos = ERR_PTR(err);
175 		goto err_vma;
176 	}
177 
178 	vma->vm = vm;
179 	list_add_tail(&vma->vm_link, &vm->unbound_list);
180 
181 	spin_lock(&obj->vma.lock);
182 	if (i915_is_ggtt(vm)) {
183 		if (unlikely(overflows_type(vma->size, u32)))
184 			goto err_unlock;
185 
186 		vma->fence_size = i915_gem_fence_size(vm->i915, vma->size,
187 						      i915_gem_object_get_tiling(obj),
188 						      i915_gem_object_get_stride(obj));
189 		if (unlikely(vma->fence_size < vma->size || /* overflow */
190 			     vma->fence_size > vm->total))
191 			goto err_unlock;
192 
193 		GEM_BUG_ON(!IS_ALIGNED(vma->fence_size, I915_GTT_MIN_ALIGNMENT));
194 
195 		vma->fence_alignment = i915_gem_fence_alignment(vm->i915, vma->size,
196 								i915_gem_object_get_tiling(obj),
197 								i915_gem_object_get_stride(obj));
198 		GEM_BUG_ON(!is_power_of_2(vma->fence_alignment));
199 
200 		__set_bit(I915_VMA_GGTT_BIT, __i915_vma_flags(vma));
201 	}
202 
203 	rb = NULL;
204 	p = &obj->vma.tree.rb_node;
205 	while (*p) {
206 		long cmp;
207 
208 		rb = *p;
209 		pos = rb_entry(rb, struct i915_vma, obj_node);
210 
211 		/*
212 		 * If the view already exists in the tree, another thread
213 		 * already created a matching vma, so return the older instance
214 		 * and dispose of ours.
215 		 */
216 		cmp = i915_vma_compare(pos, vm, view);
217 		if (cmp < 0)
218 			p = &rb->rb_right;
219 		else if (cmp > 0)
220 			p = &rb->rb_left;
221 		else
222 			goto err_unlock;
223 	}
224 	rb_link_node(&vma->obj_node, rb, p);
225 	rb_insert_color(&vma->obj_node, &obj->vma.tree);
226 
227 	if (i915_vma_is_ggtt(vma))
228 		/*
229 		 * We put the GGTT vma at the start of the vma-list, followed
230 		 * by the ppGGTT vma. This allows us to break early when
231 		 * iterating over only the GGTT vma for an object, see
232 		 * for_each_ggtt_vma()
233 		 */
234 		list_add(&vma->obj_link, &obj->vma.list);
235 	else
236 		list_add_tail(&vma->obj_link, &obj->vma.list);
237 
238 	spin_unlock(&obj->vma.lock);
239 	mutex_unlock(&vm->mutex);
240 
241 	return vma;
242 
243 err_unlock:
244 	spin_unlock(&obj->vma.lock);
245 	list_del_init(&vma->vm_link);
246 	mutex_unlock(&vm->mutex);
247 err_vma:
248 	i915_vma_free(vma);
249 	return pos;
250 }
251 
252 static struct i915_vma *
253 i915_vma_lookup(struct drm_i915_gem_object *obj,
254 	   struct i915_address_space *vm,
255 	   const struct i915_gtt_view *view)
256 {
257 	struct rb_node *rb;
258 
259 	rb = obj->vma.tree.rb_node;
260 	while (rb) {
261 		struct i915_vma *vma = rb_entry(rb, struct i915_vma, obj_node);
262 		long cmp;
263 
264 		cmp = i915_vma_compare(vma, vm, view);
265 		if (cmp == 0)
266 			return vma;
267 
268 		if (cmp < 0)
269 			rb = rb->rb_right;
270 		else
271 			rb = rb->rb_left;
272 	}
273 
274 	return NULL;
275 }
276 
277 /**
278  * i915_vma_instance - return the singleton instance of the VMA
279  * @obj: parent &struct drm_i915_gem_object to be mapped
280  * @vm: address space in which the mapping is located
281  * @view: additional mapping requirements
282  *
283  * i915_vma_instance() looks up an existing VMA of the @obj in the @vm with
284  * the same @view characteristics. If a match is not found, one is created.
285  * Once created, the VMA is kept until either the object is freed, or the
286  * address space is closed.
287  *
288  * Returns the vma, or an error pointer.
289  */
290 struct i915_vma *
291 i915_vma_instance(struct drm_i915_gem_object *obj,
292 		  struct i915_address_space *vm,
293 		  const struct i915_gtt_view *view)
294 {
295 	struct i915_vma *vma;
296 
297 	GEM_BUG_ON(view && !i915_is_ggtt_or_dpt(vm));
298 	GEM_BUG_ON(!kref_read(&vm->ref));
299 
300 	spin_lock(&obj->vma.lock);
301 	vma = i915_vma_lookup(obj, vm, view);
302 	spin_unlock(&obj->vma.lock);
303 
304 	/* vma_create() will resolve the race if another creates the vma */
305 	if (unlikely(!vma))
306 		vma = vma_create(obj, vm, view);
307 
308 	GEM_BUG_ON(!IS_ERR(vma) && i915_vma_compare(vma, vm, view));
309 	return vma;
310 }
311 
312 struct i915_vma_work {
313 	struct dma_fence_work base;
314 	struct i915_address_space *vm;
315 	struct i915_vm_pt_stash stash;
316 	struct i915_vma_resource *vma_res;
317 	struct drm_i915_gem_object *obj;
318 	struct i915_sw_dma_fence_cb cb;
319 	unsigned int pat_index;
320 	unsigned int flags;
321 };
322 
323 static void __vma_bind(struct dma_fence_work *work)
324 {
325 	struct i915_vma_work *vw = container_of(work, typeof(*vw), base);
326 	struct i915_vma_resource *vma_res = vw->vma_res;
327 
328 	/*
329 	 * We are about the bind the object, which must mean we have already
330 	 * signaled the work to potentially clear/move the pages underneath. If
331 	 * something went wrong at that stage then the object should have
332 	 * unknown_state set, in which case we need to skip the bind.
333 	 */
334 	if (i915_gem_object_has_unknown_state(vw->obj))
335 		return;
336 
337 	vma_res->ops->bind_vma(vma_res->vm, &vw->stash,
338 			       vma_res, vw->pat_index, vw->flags);
339 }
340 
341 static void __vma_release(struct dma_fence_work *work)
342 {
343 	struct i915_vma_work *vw = container_of(work, typeof(*vw), base);
344 
345 	if (vw->obj)
346 		i915_gem_object_put(vw->obj);
347 
348 	i915_vm_free_pt_stash(vw->vm, &vw->stash);
349 	if (vw->vma_res)
350 		i915_vma_resource_put(vw->vma_res);
351 }
352 
353 static const struct dma_fence_work_ops bind_ops = {
354 	.name = "bind",
355 	.work = __vma_bind,
356 	.release = __vma_release,
357 };
358 
359 struct i915_vma_work *i915_vma_work(void)
360 {
361 	struct i915_vma_work *vw;
362 
363 	vw = kzalloc(sizeof(*vw), GFP_KERNEL);
364 	if (!vw)
365 		return NULL;
366 
367 	dma_fence_work_init(&vw->base, &bind_ops);
368 	vw->base.dma.error = -EAGAIN; /* disable the worker by default */
369 
370 	return vw;
371 }
372 
373 int i915_vma_wait_for_bind(struct i915_vma *vma)
374 {
375 	int err = 0;
376 
377 	if (rcu_access_pointer(vma->active.excl.fence)) {
378 		struct dma_fence *fence;
379 
380 		rcu_read_lock();
381 		fence = dma_fence_get_rcu_safe(&vma->active.excl.fence);
382 		rcu_read_unlock();
383 		if (fence) {
384 			err = dma_fence_wait(fence, true);
385 			dma_fence_put(fence);
386 		}
387 	}
388 
389 	return err;
390 }
391 
392 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)
393 static int i915_vma_verify_bind_complete(struct i915_vma *vma)
394 {
395 	struct dma_fence *fence = i915_active_fence_get(&vma->active.excl);
396 	int err;
397 
398 	if (!fence)
399 		return 0;
400 
401 	if (dma_fence_is_signaled(fence))
402 		err = fence->error;
403 	else
404 		err = -EBUSY;
405 
406 	dma_fence_put(fence);
407 
408 	return err;
409 }
410 #else
411 #define i915_vma_verify_bind_complete(_vma) 0
412 #endif
413 
414 I915_SELFTEST_EXPORT void
415 i915_vma_resource_init_from_vma(struct i915_vma_resource *vma_res,
416 				struct i915_vma *vma)
417 {
418 	struct drm_i915_gem_object *obj = vma->obj;
419 
420 	i915_vma_resource_init(vma_res, vma->vm, vma->pages, &vma->page_sizes,
421 			       obj->mm.rsgt, i915_gem_object_is_readonly(obj),
422 			       i915_gem_object_is_lmem(obj), obj->mm.region,
423 			       vma->ops, vma->private, __i915_vma_offset(vma),
424 			       __i915_vma_size(vma), vma->size, vma->guard);
425 }
426 
427 /**
428  * i915_vma_bind - Sets up PTEs for an VMA in it's corresponding address space.
429  * @vma: VMA to map
430  * @pat_index: PAT index to set in PTE
431  * @flags: flags like global or local mapping
432  * @work: preallocated worker for allocating and binding the PTE
433  * @vma_res: pointer to a preallocated vma resource. The resource is either
434  * consumed or freed.
435  *
436  * DMA addresses are taken from the scatter-gather table of this object (or of
437  * this VMA in case of non-default GGTT views) and PTE entries set up.
438  * Note that DMA addresses are also the only part of the SG table we care about.
439  */
440 int i915_vma_bind(struct i915_vma *vma,
441 		  unsigned int pat_index,
442 		  u32 flags,
443 		  struct i915_vma_work *work,
444 		  struct i915_vma_resource *vma_res)
445 {
446 	u32 bind_flags;
447 	u32 vma_flags;
448 	int ret;
449 
450 	lockdep_assert_held(&vma->vm->mutex);
451 	GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
452 	GEM_BUG_ON(vma->size > i915_vma_size(vma));
453 
454 	if (GEM_DEBUG_WARN_ON(range_overflows(vma->node.start,
455 					      vma->node.size,
456 					      vma->vm->total))) {
457 		i915_vma_resource_free(vma_res);
458 		return -ENODEV;
459 	}
460 
461 	if (GEM_DEBUG_WARN_ON(!flags)) {
462 		i915_vma_resource_free(vma_res);
463 		return -EINVAL;
464 	}
465 
466 	bind_flags = flags;
467 	bind_flags &= I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND;
468 
469 	vma_flags = atomic_read(&vma->flags);
470 	vma_flags &= I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND;
471 
472 	bind_flags &= ~vma_flags;
473 	if (bind_flags == 0) {
474 		i915_vma_resource_free(vma_res);
475 		return 0;
476 	}
477 
478 	GEM_BUG_ON(!atomic_read(&vma->pages_count));
479 
480 	/* Wait for or await async unbinds touching our range */
481 	if (work && bind_flags & vma->vm->bind_async_flags)
482 		ret = i915_vma_resource_bind_dep_await(vma->vm,
483 						       &work->base.chain,
484 						       vma->node.start,
485 						       vma->node.size,
486 						       true,
487 						       GFP_NOWAIT |
488 						       __GFP_RETRY_MAYFAIL |
489 						       __GFP_NOWARN);
490 	else
491 		ret = i915_vma_resource_bind_dep_sync(vma->vm, vma->node.start,
492 						      vma->node.size, true);
493 	if (ret) {
494 		i915_vma_resource_free(vma_res);
495 		return ret;
496 	}
497 
498 	if (vma->resource || !vma_res) {
499 		/* Rebinding with an additional I915_VMA_*_BIND */
500 		GEM_WARN_ON(!vma_flags);
501 		i915_vma_resource_free(vma_res);
502 	} else {
503 		i915_vma_resource_init_from_vma(vma_res, vma);
504 		vma->resource = vma_res;
505 	}
506 	trace_i915_vma_bind(vma, bind_flags);
507 	if (work && bind_flags & vma->vm->bind_async_flags) {
508 		struct dma_fence *prev;
509 
510 		work->vma_res = i915_vma_resource_get(vma->resource);
511 		work->pat_index = pat_index;
512 		work->flags = bind_flags;
513 
514 		/*
515 		 * Note we only want to chain up to the migration fence on
516 		 * the pages (not the object itself). As we don't track that,
517 		 * yet, we have to use the exclusive fence instead.
518 		 *
519 		 * Also note that we do not want to track the async vma as
520 		 * part of the obj->resv->excl_fence as it only affects
521 		 * execution and not content or object's backing store lifetime.
522 		 */
523 		prev = i915_active_set_exclusive(&vma->active, &work->base.dma);
524 		if (prev) {
525 			__i915_sw_fence_await_dma_fence(&work->base.chain,
526 							prev,
527 							&work->cb);
528 			dma_fence_put(prev);
529 		}
530 
531 		work->base.dma.error = 0; /* enable the queue_work() */
532 		work->obj = i915_gem_object_get(vma->obj);
533 	} else {
534 		ret = i915_gem_object_wait_moving_fence(vma->obj, true);
535 		if (ret) {
536 			i915_vma_resource_free(vma->resource);
537 			vma->resource = NULL;
538 
539 			return ret;
540 		}
541 		vma->ops->bind_vma(vma->vm, NULL, vma->resource, pat_index,
542 				   bind_flags);
543 	}
544 
545 	atomic_or(bind_flags, &vma->flags);
546 	return 0;
547 }
548 
549 void __iomem *i915_vma_pin_iomap(struct i915_vma *vma)
550 {
551 	void __iomem *ptr;
552 	int err;
553 
554 	if (WARN_ON_ONCE(vma->obj->flags & I915_BO_ALLOC_GPU_ONLY))
555 		return IOMEM_ERR_PTR(-EINVAL);
556 
557 	GEM_BUG_ON(!i915_vma_is_ggtt(vma));
558 	GEM_BUG_ON(!i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND));
559 	GEM_BUG_ON(i915_vma_verify_bind_complete(vma));
560 
561 	ptr = READ_ONCE(vma->iomap);
562 	if (ptr == NULL) {
563 		/*
564 		 * TODO: consider just using i915_gem_object_pin_map() for lmem
565 		 * instead, which already supports mapping non-contiguous chunks
566 		 * of pages, that way we can also drop the
567 		 * I915_BO_ALLOC_CONTIGUOUS when allocating the object.
568 		 */
569 		if (i915_gem_object_is_lmem(vma->obj)) {
570 			ptr = i915_gem_object_lmem_io_map(vma->obj, 0,
571 							  vma->obj->base.size);
572 		} else if (i915_vma_is_map_and_fenceable(vma)) {
573 			ptr = io_mapping_map_wc(&i915_vm_to_ggtt(vma->vm)->iomap,
574 						i915_vma_offset(vma),
575 						i915_vma_size(vma));
576 		} else {
577 			ptr = (void __iomem *)
578 				i915_gem_object_pin_map(vma->obj, I915_MAP_WC);
579 			if (IS_ERR(ptr)) {
580 				err = PTR_ERR(ptr);
581 				goto err;
582 			}
583 			ptr = page_pack_bits(ptr, 1);
584 		}
585 
586 		if (ptr == NULL) {
587 			err = -ENOMEM;
588 			goto err;
589 		}
590 
591 		if (unlikely(cmpxchg(&vma->iomap, NULL, ptr))) {
592 			if (page_unmask_bits(ptr))
593 				__i915_gem_object_release_map(vma->obj);
594 			else
595 				io_mapping_unmap(ptr);
596 			ptr = vma->iomap;
597 		}
598 	}
599 
600 	__i915_vma_pin(vma);
601 
602 	err = i915_vma_pin_fence(vma);
603 	if (err)
604 		goto err_unpin;
605 
606 	i915_vma_set_ggtt_write(vma);
607 
608 	/* NB Access through the GTT requires the device to be awake. */
609 	return page_mask_bits(ptr);
610 
611 err_unpin:
612 	__i915_vma_unpin(vma);
613 err:
614 	return IOMEM_ERR_PTR(err);
615 }
616 
617 void i915_vma_flush_writes(struct i915_vma *vma)
618 {
619 	if (i915_vma_unset_ggtt_write(vma))
620 		intel_gt_flush_ggtt_writes(vma->vm->gt);
621 }
622 
623 void i915_vma_unpin_iomap(struct i915_vma *vma)
624 {
625 	GEM_BUG_ON(vma->iomap == NULL);
626 
627 	/* XXX We keep the mapping until __i915_vma_unbind()/evict() */
628 
629 	i915_vma_flush_writes(vma);
630 
631 	i915_vma_unpin_fence(vma);
632 	i915_vma_unpin(vma);
633 }
634 
635 void i915_vma_unpin_and_release(struct i915_vma **p_vma, unsigned int flags)
636 {
637 	struct i915_vma *vma;
638 	struct drm_i915_gem_object *obj;
639 
640 	vma = fetch_and_zero(p_vma);
641 	if (!vma)
642 		return;
643 
644 	obj = vma->obj;
645 	GEM_BUG_ON(!obj);
646 
647 	i915_vma_unpin(vma);
648 
649 	if (flags & I915_VMA_RELEASE_MAP)
650 		i915_gem_object_unpin_map(obj);
651 
652 	i915_gem_object_put(obj);
653 }
654 
655 bool i915_vma_misplaced(const struct i915_vma *vma,
656 			u64 size, u64 alignment, u64 flags)
657 {
658 	if (!drm_mm_node_allocated(&vma->node))
659 		return false;
660 
661 	if (test_bit(I915_VMA_ERROR_BIT, __i915_vma_flags(vma)))
662 		return true;
663 
664 	if (i915_vma_size(vma) < size)
665 		return true;
666 
667 	GEM_BUG_ON(alignment && !is_power_of_2(alignment));
668 	if (alignment && !IS_ALIGNED(i915_vma_offset(vma), alignment))
669 		return true;
670 
671 	if (flags & PIN_MAPPABLE && !i915_vma_is_map_and_fenceable(vma))
672 		return true;
673 
674 	if (flags & PIN_OFFSET_BIAS &&
675 	    i915_vma_offset(vma) < (flags & PIN_OFFSET_MASK))
676 		return true;
677 
678 	if (flags & PIN_OFFSET_FIXED &&
679 	    i915_vma_offset(vma) != (flags & PIN_OFFSET_MASK))
680 		return true;
681 
682 	if (flags & PIN_OFFSET_GUARD &&
683 	    vma->guard < (flags & PIN_OFFSET_MASK))
684 		return true;
685 
686 	return false;
687 }
688 
689 void __i915_vma_set_map_and_fenceable(struct i915_vma *vma)
690 {
691 	bool mappable, fenceable;
692 
693 	GEM_BUG_ON(!i915_vma_is_ggtt(vma));
694 	GEM_BUG_ON(!vma->fence_size);
695 
696 	fenceable = (i915_vma_size(vma) >= vma->fence_size &&
697 		     IS_ALIGNED(i915_vma_offset(vma), vma->fence_alignment));
698 
699 	mappable = i915_ggtt_offset(vma) + vma->fence_size <=
700 		   i915_vm_to_ggtt(vma->vm)->mappable_end;
701 
702 	if (mappable && fenceable)
703 		set_bit(I915_VMA_CAN_FENCE_BIT, __i915_vma_flags(vma));
704 	else
705 		clear_bit(I915_VMA_CAN_FENCE_BIT, __i915_vma_flags(vma));
706 }
707 
708 bool i915_gem_valid_gtt_space(struct i915_vma *vma, unsigned long color)
709 {
710 	struct drm_mm_node *node = &vma->node;
711 	struct drm_mm_node *other;
712 
713 	/*
714 	 * On some machines we have to be careful when putting differing types
715 	 * of snoopable memory together to avoid the prefetcher crossing memory
716 	 * domains and dying. During vm initialisation, we decide whether or not
717 	 * these constraints apply and set the drm_mm.color_adjust
718 	 * appropriately.
719 	 */
720 	if (!i915_vm_has_cache_coloring(vma->vm))
721 		return true;
722 
723 	/* Only valid to be called on an already inserted vma */
724 	GEM_BUG_ON(!drm_mm_node_allocated(node));
725 	GEM_BUG_ON(list_empty(&node->node_list));
726 
727 	other = list_prev_entry(node, node_list);
728 	if (i915_node_color_differs(other, color) &&
729 	    !drm_mm_hole_follows(other))
730 		return false;
731 
732 	other = list_next_entry(node, node_list);
733 	if (i915_node_color_differs(other, color) &&
734 	    !drm_mm_hole_follows(node))
735 		return false;
736 
737 	return true;
738 }
739 
740 /**
741  * i915_vma_insert - finds a slot for the vma in its address space
742  * @vma: the vma
743  * @ww: An optional struct i915_gem_ww_ctx
744  * @size: requested size in bytes (can be larger than the VMA)
745  * @alignment: required alignment
746  * @flags: mask of PIN_* flags to use
747  *
748  * First we try to allocate some free space that meets the requirements for
749  * the VMA. Failiing that, if the flags permit, it will evict an old VMA,
750  * preferrably the oldest idle entry to make room for the new VMA.
751  *
752  * Returns:
753  * 0 on success, negative error code otherwise.
754  */
755 static int
756 i915_vma_insert(struct i915_vma *vma, struct i915_gem_ww_ctx *ww,
757 		u64 size, u64 alignment, u64 flags)
758 {
759 	unsigned long color, guard;
760 	u64 start, end;
761 	int ret;
762 
763 	GEM_BUG_ON(i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND));
764 	GEM_BUG_ON(drm_mm_node_allocated(&vma->node));
765 	GEM_BUG_ON(hweight64(flags & (PIN_OFFSET_GUARD | PIN_OFFSET_FIXED | PIN_OFFSET_BIAS)) > 1);
766 
767 	size = max(size, vma->size);
768 	alignment = max_t(typeof(alignment), alignment, vma->display_alignment);
769 	if (flags & PIN_MAPPABLE) {
770 		size = max_t(typeof(size), size, vma->fence_size);
771 		alignment = max_t(typeof(alignment),
772 				  alignment, vma->fence_alignment);
773 	}
774 
775 	GEM_BUG_ON(!IS_ALIGNED(size, I915_GTT_PAGE_SIZE));
776 	GEM_BUG_ON(!IS_ALIGNED(alignment, I915_GTT_MIN_ALIGNMENT));
777 	GEM_BUG_ON(!is_power_of_2(alignment));
778 
779 	guard = vma->guard; /* retain guard across rebinds */
780 	if (flags & PIN_OFFSET_GUARD) {
781 		GEM_BUG_ON(overflows_type(flags & PIN_OFFSET_MASK, u32));
782 		guard = max_t(u32, guard, flags & PIN_OFFSET_MASK);
783 	}
784 	/*
785 	 * As we align the node upon insertion, but the hardware gets
786 	 * node.start + guard, the easiest way to make that work is
787 	 * to make the guard a multiple of the alignment size.
788 	 */
789 	guard = ALIGN(guard, alignment);
790 
791 	start = flags & PIN_OFFSET_BIAS ? flags & PIN_OFFSET_MASK : 0;
792 	GEM_BUG_ON(!IS_ALIGNED(start, I915_GTT_PAGE_SIZE));
793 
794 	end = vma->vm->total;
795 	if (flags & PIN_MAPPABLE)
796 		end = min_t(u64, end, i915_vm_to_ggtt(vma->vm)->mappable_end);
797 	if (flags & PIN_ZONE_4G)
798 		end = min_t(u64, end, (1ULL << 32) - I915_GTT_PAGE_SIZE);
799 	GEM_BUG_ON(!IS_ALIGNED(end, I915_GTT_PAGE_SIZE));
800 
801 	alignment = max(alignment, i915_vm_obj_min_alignment(vma->vm, vma->obj));
802 
803 	/*
804 	 * If binding the object/GGTT view requires more space than the entire
805 	 * aperture has, reject it early before evicting everything in a vain
806 	 * attempt to find space.
807 	 */
808 	if (size > end - 2 * guard) {
809 		drm_dbg(vma->obj->base.dev,
810 			"Attempting to bind an object larger than the aperture: request=%llu > %s aperture=%llu\n",
811 			size, flags & PIN_MAPPABLE ? "mappable" : "total", end);
812 		return -ENOSPC;
813 	}
814 
815 	color = 0;
816 
817 	if (i915_vm_has_cache_coloring(vma->vm))
818 		color = vma->obj->pat_index;
819 
820 	if (flags & PIN_OFFSET_FIXED) {
821 		u64 offset = flags & PIN_OFFSET_MASK;
822 		if (!IS_ALIGNED(offset, alignment) ||
823 		    range_overflows(offset, size, end))
824 			return -EINVAL;
825 		/*
826 		 * The caller knows not of the guard added by others and
827 		 * requests for the offset of the start of its buffer
828 		 * to be fixed, which may not be the same as the position
829 		 * of the vma->node due to the guard pages.
830 		 */
831 		if (offset < guard || offset + size > end - guard)
832 			return -ENOSPC;
833 
834 		ret = i915_gem_gtt_reserve(vma->vm, ww, &vma->node,
835 					   size + 2 * guard,
836 					   offset - guard,
837 					   color, flags);
838 		if (ret)
839 			return ret;
840 	} else {
841 		size += 2 * guard;
842 		/*
843 		 * We only support huge gtt pages through the 48b PPGTT,
844 		 * however we also don't want to force any alignment for
845 		 * objects which need to be tightly packed into the low 32bits.
846 		 *
847 		 * Note that we assume that GGTT are limited to 4GiB for the
848 		 * forseeable future. See also i915_ggtt_offset().
849 		 */
850 		if (upper_32_bits(end - 1) &&
851 		    vma->page_sizes.sg > I915_GTT_PAGE_SIZE &&
852 		    !HAS_64K_PAGES(vma->vm->i915)) {
853 			/*
854 			 * We can't mix 64K and 4K PTEs in the same page-table
855 			 * (2M block), and so to avoid the ugliness and
856 			 * complexity of coloring we opt for just aligning 64K
857 			 * objects to 2M.
858 			 */
859 			u64 page_alignment =
860 				rounddown_pow_of_two(vma->page_sizes.sg |
861 						     I915_GTT_PAGE_SIZE_2M);
862 
863 			/*
864 			 * Check we don't expand for the limited Global GTT
865 			 * (mappable aperture is even more precious!). This
866 			 * also checks that we exclude the aliasing-ppgtt.
867 			 */
868 			GEM_BUG_ON(i915_vma_is_ggtt(vma));
869 
870 			alignment = max(alignment, page_alignment);
871 
872 			if (vma->page_sizes.sg & I915_GTT_PAGE_SIZE_64K)
873 				size = round_up(size, I915_GTT_PAGE_SIZE_2M);
874 		}
875 
876 		ret = i915_gem_gtt_insert(vma->vm, ww, &vma->node,
877 					  size, alignment, color,
878 					  start, end, flags);
879 		if (ret)
880 			return ret;
881 
882 		GEM_BUG_ON(vma->node.start < start);
883 		GEM_BUG_ON(vma->node.start + vma->node.size > end);
884 	}
885 	GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
886 	GEM_BUG_ON(!i915_gem_valid_gtt_space(vma, color));
887 
888 	list_move_tail(&vma->vm_link, &vma->vm->bound_list);
889 	vma->guard = guard;
890 
891 	return 0;
892 }
893 
894 static void
895 i915_vma_detach(struct i915_vma *vma)
896 {
897 	GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
898 	GEM_BUG_ON(i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND));
899 
900 	/*
901 	 * And finally now the object is completely decoupled from this
902 	 * vma, we can drop its hold on the backing storage and allow
903 	 * it to be reaped by the shrinker.
904 	 */
905 	list_move_tail(&vma->vm_link, &vma->vm->unbound_list);
906 }
907 
908 static bool try_qad_pin(struct i915_vma *vma, unsigned int flags)
909 {
910 	unsigned int bound;
911 
912 	bound = atomic_read(&vma->flags);
913 
914 	if (flags & PIN_VALIDATE) {
915 		flags &= I915_VMA_BIND_MASK;
916 
917 		return (flags & bound) == flags;
918 	}
919 
920 	/* with the lock mandatory for unbind, we don't race here */
921 	flags &= I915_VMA_BIND_MASK;
922 	do {
923 		if (unlikely(flags & ~bound))
924 			return false;
925 
926 		if (unlikely(bound & (I915_VMA_OVERFLOW | I915_VMA_ERROR)))
927 			return false;
928 
929 		GEM_BUG_ON(((bound + 1) & I915_VMA_PIN_MASK) == 0);
930 	} while (!atomic_try_cmpxchg(&vma->flags, &bound, bound + 1));
931 
932 	return true;
933 }
934 
935 static struct scatterlist *
936 rotate_pages(struct drm_i915_gem_object *obj, unsigned int offset,
937 	     unsigned int width, unsigned int height,
938 	     unsigned int src_stride, unsigned int dst_stride,
939 	     struct sg_table *st, struct scatterlist *sg)
940 {
941 	unsigned int column, row;
942 	pgoff_t src_idx;
943 
944 	for (column = 0; column < width; column++) {
945 		unsigned int left;
946 
947 		src_idx = src_stride * (height - 1) + column + offset;
948 		for (row = 0; row < height; row++) {
949 			st->nents++;
950 			/*
951 			 * We don't need the pages, but need to initialize
952 			 * the entries so the sg list can be happily traversed.
953 			 * The only thing we need are DMA addresses.
954 			 */
955 			sg_set_page(sg, NULL, I915_GTT_PAGE_SIZE, 0);
956 			sg_dma_address(sg) =
957 				i915_gem_object_get_dma_address(obj, src_idx);
958 			sg_dma_len(sg) = I915_GTT_PAGE_SIZE;
959 			sg = sg_next(sg);
960 			src_idx -= src_stride;
961 		}
962 
963 		left = (dst_stride - height) * I915_GTT_PAGE_SIZE;
964 
965 		if (!left)
966 			continue;
967 
968 		st->nents++;
969 
970 		/*
971 		 * The DE ignores the PTEs for the padding tiles, the sg entry
972 		 * here is just a conenience to indicate how many padding PTEs
973 		 * to insert at this spot.
974 		 */
975 		sg_set_page(sg, NULL, left, 0);
976 		sg_dma_address(sg) = 0;
977 		sg_dma_len(sg) = left;
978 		sg = sg_next(sg);
979 	}
980 
981 	return sg;
982 }
983 
984 static noinline struct sg_table *
985 intel_rotate_pages(struct intel_rotation_info *rot_info,
986 		   struct drm_i915_gem_object *obj)
987 {
988 	unsigned int size = intel_rotation_info_size(rot_info);
989 	struct drm_i915_private *i915 = to_i915(obj->base.dev);
990 	struct sg_table *st;
991 	struct scatterlist *sg;
992 	int ret = -ENOMEM;
993 	int i;
994 
995 	/* Allocate target SG list. */
996 	st = kmalloc(sizeof(*st), GFP_KERNEL);
997 	if (!st)
998 		goto err_st_alloc;
999 
1000 	ret = sg_alloc_table(st, size, GFP_KERNEL);
1001 	if (ret)
1002 		goto err_sg_alloc;
1003 
1004 	st->nents = 0;
1005 	sg = st->sgl;
1006 
1007 	for (i = 0 ; i < ARRAY_SIZE(rot_info->plane); i++)
1008 		sg = rotate_pages(obj, rot_info->plane[i].offset,
1009 				  rot_info->plane[i].width, rot_info->plane[i].height,
1010 				  rot_info->plane[i].src_stride,
1011 				  rot_info->plane[i].dst_stride,
1012 				  st, sg);
1013 
1014 	return st;
1015 
1016 err_sg_alloc:
1017 	kfree(st);
1018 err_st_alloc:
1019 
1020 	drm_dbg(&i915->drm, "Failed to create rotated mapping for object size %zu! (%ux%u tiles, %u pages)\n",
1021 		obj->base.size, rot_info->plane[0].width,
1022 		rot_info->plane[0].height, size);
1023 
1024 	return ERR_PTR(ret);
1025 }
1026 
1027 static struct scatterlist *
1028 add_padding_pages(unsigned int count,
1029 		  struct sg_table *st, struct scatterlist *sg)
1030 {
1031 	st->nents++;
1032 
1033 	/*
1034 	 * The DE ignores the PTEs for the padding tiles, the sg entry
1035 	 * here is just a convenience to indicate how many padding PTEs
1036 	 * to insert at this spot.
1037 	 */
1038 	sg_set_page(sg, NULL, count * I915_GTT_PAGE_SIZE, 0);
1039 	sg_dma_address(sg) = 0;
1040 	sg_dma_len(sg) = count * I915_GTT_PAGE_SIZE;
1041 	sg = sg_next(sg);
1042 
1043 	return sg;
1044 }
1045 
1046 static struct scatterlist *
1047 remap_tiled_color_plane_pages(struct drm_i915_gem_object *obj,
1048 			      unsigned long offset, unsigned int alignment_pad,
1049 			      unsigned int width, unsigned int height,
1050 			      unsigned int src_stride, unsigned int dst_stride,
1051 			      struct sg_table *st, struct scatterlist *sg,
1052 			      unsigned int *gtt_offset)
1053 {
1054 	unsigned int row;
1055 
1056 	if (!width || !height)
1057 		return sg;
1058 
1059 	if (alignment_pad)
1060 		sg = add_padding_pages(alignment_pad, st, sg);
1061 
1062 	for (row = 0; row < height; row++) {
1063 		unsigned int left = width * I915_GTT_PAGE_SIZE;
1064 
1065 		while (left) {
1066 			dma_addr_t addr;
1067 			unsigned int length;
1068 
1069 			/*
1070 			 * We don't need the pages, but need to initialize
1071 			 * the entries so the sg list can be happily traversed.
1072 			 * The only thing we need are DMA addresses.
1073 			 */
1074 
1075 			addr = i915_gem_object_get_dma_address_len(obj, offset, &length);
1076 
1077 			length = min(left, length);
1078 
1079 			st->nents++;
1080 
1081 			sg_set_page(sg, NULL, length, 0);
1082 			sg_dma_address(sg) = addr;
1083 			sg_dma_len(sg) = length;
1084 			sg = sg_next(sg);
1085 
1086 			offset += length / I915_GTT_PAGE_SIZE;
1087 			left -= length;
1088 		}
1089 
1090 		offset += src_stride - width;
1091 
1092 		left = (dst_stride - width) * I915_GTT_PAGE_SIZE;
1093 
1094 		if (!left)
1095 			continue;
1096 
1097 		sg = add_padding_pages(left >> PAGE_SHIFT, st, sg);
1098 	}
1099 
1100 	*gtt_offset += alignment_pad + dst_stride * height;
1101 
1102 	return sg;
1103 }
1104 
1105 static struct scatterlist *
1106 remap_contiguous_pages(struct drm_i915_gem_object *obj,
1107 		       pgoff_t obj_offset,
1108 		       unsigned int count,
1109 		       struct sg_table *st, struct scatterlist *sg)
1110 {
1111 	struct scatterlist *iter;
1112 	unsigned int offset;
1113 
1114 	iter = i915_gem_object_get_sg_dma(obj, obj_offset, &offset);
1115 	GEM_BUG_ON(!iter);
1116 
1117 	do {
1118 		unsigned int len;
1119 
1120 		len = min(sg_dma_len(iter) - (offset << PAGE_SHIFT),
1121 			  count << PAGE_SHIFT);
1122 		sg_set_page(sg, NULL, len, 0);
1123 		sg_dma_address(sg) =
1124 			sg_dma_address(iter) + (offset << PAGE_SHIFT);
1125 		sg_dma_len(sg) = len;
1126 
1127 		st->nents++;
1128 		count -= len >> PAGE_SHIFT;
1129 		if (count == 0)
1130 			return sg;
1131 
1132 		sg = __sg_next(sg);
1133 		iter = __sg_next(iter);
1134 		offset = 0;
1135 	} while (1);
1136 }
1137 
1138 static struct scatterlist *
1139 remap_linear_color_plane_pages(struct drm_i915_gem_object *obj,
1140 			       pgoff_t obj_offset, unsigned int alignment_pad,
1141 			       unsigned int size,
1142 			       struct sg_table *st, struct scatterlist *sg,
1143 			       unsigned int *gtt_offset)
1144 {
1145 	if (!size)
1146 		return sg;
1147 
1148 	if (alignment_pad)
1149 		sg = add_padding_pages(alignment_pad, st, sg);
1150 
1151 	sg = remap_contiguous_pages(obj, obj_offset, size, st, sg);
1152 	sg = sg_next(sg);
1153 
1154 	*gtt_offset += alignment_pad + size;
1155 
1156 	return sg;
1157 }
1158 
1159 static struct scatterlist *
1160 remap_color_plane_pages(const struct intel_remapped_info *rem_info,
1161 			struct drm_i915_gem_object *obj,
1162 			int color_plane,
1163 			struct sg_table *st, struct scatterlist *sg,
1164 			unsigned int *gtt_offset)
1165 {
1166 	unsigned int alignment_pad = 0;
1167 
1168 	if (rem_info->plane_alignment)
1169 		alignment_pad = ALIGN(*gtt_offset, rem_info->plane_alignment) - *gtt_offset;
1170 
1171 	if (rem_info->plane[color_plane].linear)
1172 		sg = remap_linear_color_plane_pages(obj,
1173 						    rem_info->plane[color_plane].offset,
1174 						    alignment_pad,
1175 						    rem_info->plane[color_plane].size,
1176 						    st, sg,
1177 						    gtt_offset);
1178 
1179 	else
1180 		sg = remap_tiled_color_plane_pages(obj,
1181 						   rem_info->plane[color_plane].offset,
1182 						   alignment_pad,
1183 						   rem_info->plane[color_plane].width,
1184 						   rem_info->plane[color_plane].height,
1185 						   rem_info->plane[color_plane].src_stride,
1186 						   rem_info->plane[color_plane].dst_stride,
1187 						   st, sg,
1188 						   gtt_offset);
1189 
1190 	return sg;
1191 }
1192 
1193 static noinline struct sg_table *
1194 intel_remap_pages(struct intel_remapped_info *rem_info,
1195 		  struct drm_i915_gem_object *obj)
1196 {
1197 	unsigned int size = intel_remapped_info_size(rem_info);
1198 	struct drm_i915_private *i915 = to_i915(obj->base.dev);
1199 	struct sg_table *st;
1200 	struct scatterlist *sg;
1201 	unsigned int gtt_offset = 0;
1202 	int ret = -ENOMEM;
1203 	int i;
1204 
1205 	/* Allocate target SG list. */
1206 	st = kmalloc(sizeof(*st), GFP_KERNEL);
1207 	if (!st)
1208 		goto err_st_alloc;
1209 
1210 	ret = sg_alloc_table(st, size, GFP_KERNEL);
1211 	if (ret)
1212 		goto err_sg_alloc;
1213 
1214 	st->nents = 0;
1215 	sg = st->sgl;
1216 
1217 	for (i = 0 ; i < ARRAY_SIZE(rem_info->plane); i++)
1218 		sg = remap_color_plane_pages(rem_info, obj, i, st, sg, &gtt_offset);
1219 
1220 	i915_sg_trim(st);
1221 
1222 	return st;
1223 
1224 err_sg_alloc:
1225 	kfree(st);
1226 err_st_alloc:
1227 
1228 	drm_dbg(&i915->drm, "Failed to create remapped mapping for object size %zu! (%ux%u tiles, %u pages)\n",
1229 		obj->base.size, rem_info->plane[0].width,
1230 		rem_info->plane[0].height, size);
1231 
1232 	return ERR_PTR(ret);
1233 }
1234 
1235 static noinline struct sg_table *
1236 intel_partial_pages(const struct i915_gtt_view *view,
1237 		    struct drm_i915_gem_object *obj)
1238 {
1239 	struct sg_table *st;
1240 	struct scatterlist *sg;
1241 	unsigned int count = view->partial.size;
1242 	int ret = -ENOMEM;
1243 
1244 	st = kmalloc(sizeof(*st), GFP_KERNEL);
1245 	if (!st)
1246 		goto err_st_alloc;
1247 
1248 	ret = sg_alloc_table(st, count, GFP_KERNEL);
1249 	if (ret)
1250 		goto err_sg_alloc;
1251 
1252 	st->nents = 0;
1253 
1254 	sg = remap_contiguous_pages(obj, view->partial.offset, count, st, st->sgl);
1255 
1256 	sg_mark_end(sg);
1257 	i915_sg_trim(st); /* Drop any unused tail entries. */
1258 
1259 	return st;
1260 
1261 err_sg_alloc:
1262 	kfree(st);
1263 err_st_alloc:
1264 	return ERR_PTR(ret);
1265 }
1266 
1267 static int
1268 __i915_vma_get_pages(struct i915_vma *vma)
1269 {
1270 	struct sg_table *pages;
1271 
1272 	/*
1273 	 * The vma->pages are only valid within the lifespan of the borrowed
1274 	 * obj->mm.pages. When the obj->mm.pages sg_table is regenerated, so
1275 	 * must be the vma->pages. A simple rule is that vma->pages must only
1276 	 * be accessed when the obj->mm.pages are pinned.
1277 	 */
1278 	GEM_BUG_ON(!i915_gem_object_has_pinned_pages(vma->obj));
1279 
1280 	switch (vma->gtt_view.type) {
1281 	default:
1282 		GEM_BUG_ON(vma->gtt_view.type);
1283 		fallthrough;
1284 	case I915_GTT_VIEW_NORMAL:
1285 		pages = vma->obj->mm.pages;
1286 		break;
1287 
1288 	case I915_GTT_VIEW_ROTATED:
1289 		pages =
1290 			intel_rotate_pages(&vma->gtt_view.rotated, vma->obj);
1291 		break;
1292 
1293 	case I915_GTT_VIEW_REMAPPED:
1294 		pages =
1295 			intel_remap_pages(&vma->gtt_view.remapped, vma->obj);
1296 		break;
1297 
1298 	case I915_GTT_VIEW_PARTIAL:
1299 		pages = intel_partial_pages(&vma->gtt_view, vma->obj);
1300 		break;
1301 	}
1302 
1303 	if (IS_ERR(pages)) {
1304 		drm_err(&vma->vm->i915->drm,
1305 			"Failed to get pages for VMA view type %u (%ld)!\n",
1306 			vma->gtt_view.type, PTR_ERR(pages));
1307 		return PTR_ERR(pages);
1308 	}
1309 
1310 	vma->pages = pages;
1311 
1312 	return 0;
1313 }
1314 
1315 I915_SELFTEST_EXPORT int i915_vma_get_pages(struct i915_vma *vma)
1316 {
1317 	int err;
1318 
1319 	if (atomic_add_unless(&vma->pages_count, 1, 0))
1320 		return 0;
1321 
1322 	err = i915_gem_object_pin_pages(vma->obj);
1323 	if (err)
1324 		return err;
1325 
1326 	err = __i915_vma_get_pages(vma);
1327 	if (err)
1328 		goto err_unpin;
1329 
1330 	vma->page_sizes = vma->obj->mm.page_sizes;
1331 	atomic_inc(&vma->pages_count);
1332 
1333 	return 0;
1334 
1335 err_unpin:
1336 	__i915_gem_object_unpin_pages(vma->obj);
1337 
1338 	return err;
1339 }
1340 
1341 void vma_invalidate_tlb(struct i915_address_space *vm, u32 *tlb)
1342 {
1343 	struct intel_gt *gt;
1344 	int id;
1345 
1346 	if (!tlb)
1347 		return;
1348 
1349 	/*
1350 	 * Before we release the pages that were bound by this vma, we
1351 	 * must invalidate all the TLBs that may still have a reference
1352 	 * back to our physical address. It only needs to be done once,
1353 	 * so after updating the PTE to point away from the pages, record
1354 	 * the most recent TLB invalidation seqno, and if we have not yet
1355 	 * flushed the TLBs upon release, perform a full invalidation.
1356 	 */
1357 	for_each_gt(gt, vm->i915, id)
1358 		WRITE_ONCE(tlb[id],
1359 			   intel_gt_next_invalidate_tlb_full(gt));
1360 }
1361 
1362 static void __vma_put_pages(struct i915_vma *vma, unsigned int count)
1363 {
1364 	/* We allocate under vma_get_pages, so beware the shrinker */
1365 	GEM_BUG_ON(atomic_read(&vma->pages_count) < count);
1366 
1367 	if (atomic_sub_return(count, &vma->pages_count) == 0) {
1368 		if (vma->pages != vma->obj->mm.pages) {
1369 			sg_free_table(vma->pages);
1370 			kfree(vma->pages);
1371 		}
1372 		vma->pages = NULL;
1373 
1374 		i915_gem_object_unpin_pages(vma->obj);
1375 	}
1376 }
1377 
1378 I915_SELFTEST_EXPORT void i915_vma_put_pages(struct i915_vma *vma)
1379 {
1380 	if (atomic_add_unless(&vma->pages_count, -1, 1))
1381 		return;
1382 
1383 	__vma_put_pages(vma, 1);
1384 }
1385 
1386 static void vma_unbind_pages(struct i915_vma *vma)
1387 {
1388 	unsigned int count;
1389 
1390 	lockdep_assert_held(&vma->vm->mutex);
1391 
1392 	/* The upper portion of pages_count is the number of bindings */
1393 	count = atomic_read(&vma->pages_count);
1394 	count >>= I915_VMA_PAGES_BIAS;
1395 	GEM_BUG_ON(!count);
1396 
1397 	__vma_put_pages(vma, count | count << I915_VMA_PAGES_BIAS);
1398 }
1399 
1400 int i915_vma_pin_ww(struct i915_vma *vma, struct i915_gem_ww_ctx *ww,
1401 		    u64 size, u64 alignment, u64 flags)
1402 {
1403 	struct i915_vma_work *work = NULL;
1404 	struct dma_fence *moving = NULL;
1405 	struct i915_vma_resource *vma_res = NULL;
1406 	intel_wakeref_t wakeref = 0;
1407 	unsigned int bound;
1408 	int err;
1409 
1410 	assert_vma_held(vma);
1411 	GEM_BUG_ON(!ww);
1412 
1413 	BUILD_BUG_ON(PIN_GLOBAL != I915_VMA_GLOBAL_BIND);
1414 	BUILD_BUG_ON(PIN_USER != I915_VMA_LOCAL_BIND);
1415 
1416 	GEM_BUG_ON(!(flags & (PIN_USER | PIN_GLOBAL)));
1417 
1418 	/* First try and grab the pin without rebinding the vma */
1419 	if (try_qad_pin(vma, flags))
1420 		return 0;
1421 
1422 	err = i915_vma_get_pages(vma);
1423 	if (err)
1424 		return err;
1425 
1426 	if (flags & PIN_GLOBAL)
1427 		wakeref = intel_runtime_pm_get(&vma->vm->i915->runtime_pm);
1428 
1429 	if (flags & vma->vm->bind_async_flags) {
1430 		/* lock VM */
1431 		err = i915_vm_lock_objects(vma->vm, ww);
1432 		if (err)
1433 			goto err_rpm;
1434 
1435 		work = i915_vma_work();
1436 		if (!work) {
1437 			err = -ENOMEM;
1438 			goto err_rpm;
1439 		}
1440 
1441 		work->vm = vma->vm;
1442 
1443 		err = i915_gem_object_get_moving_fence(vma->obj, &moving);
1444 		if (err)
1445 			goto err_rpm;
1446 
1447 		dma_fence_work_chain(&work->base, moving);
1448 
1449 		/* Allocate enough page directories to used PTE */
1450 		if (vma->vm->allocate_va_range) {
1451 			err = i915_vm_alloc_pt_stash(vma->vm,
1452 						     &work->stash,
1453 						     vma->size);
1454 			if (err)
1455 				goto err_fence;
1456 
1457 			err = i915_vm_map_pt_stash(vma->vm, &work->stash);
1458 			if (err)
1459 				goto err_fence;
1460 		}
1461 	}
1462 
1463 	vma_res = i915_vma_resource_alloc();
1464 	if (IS_ERR(vma_res)) {
1465 		err = PTR_ERR(vma_res);
1466 		goto err_fence;
1467 	}
1468 
1469 	/*
1470 	 * Differentiate between user/kernel vma inside the aliasing-ppgtt.
1471 	 *
1472 	 * We conflate the Global GTT with the user's vma when using the
1473 	 * aliasing-ppgtt, but it is still vitally important to try and
1474 	 * keep the use cases distinct. For example, userptr objects are
1475 	 * not allowed inside the Global GTT as that will cause lock
1476 	 * inversions when we have to evict them the mmu_notifier callbacks -
1477 	 * but they are allowed to be part of the user ppGTT which can never
1478 	 * be mapped. As such we try to give the distinct users of the same
1479 	 * mutex, distinct lockclasses [equivalent to how we keep i915_ggtt
1480 	 * and i915_ppgtt separate].
1481 	 *
1482 	 * NB this may cause us to mask real lock inversions -- while the
1483 	 * code is safe today, lockdep may not be able to spot future
1484 	 * transgressions.
1485 	 */
1486 	err = mutex_lock_interruptible_nested(&vma->vm->mutex,
1487 					      !(flags & PIN_GLOBAL));
1488 	if (err)
1489 		goto err_vma_res;
1490 
1491 	/* No more allocations allowed now we hold vm->mutex */
1492 
1493 	if (unlikely(i915_vma_is_closed(vma))) {
1494 		err = -ENOENT;
1495 		goto err_unlock;
1496 	}
1497 
1498 	bound = atomic_read(&vma->flags);
1499 	if (unlikely(bound & I915_VMA_ERROR)) {
1500 		err = -ENOMEM;
1501 		goto err_unlock;
1502 	}
1503 
1504 	if (unlikely(!((bound + 1) & I915_VMA_PIN_MASK))) {
1505 		err = -EAGAIN; /* pins are meant to be fairly temporary */
1506 		goto err_unlock;
1507 	}
1508 
1509 	if (unlikely(!(flags & ~bound & I915_VMA_BIND_MASK))) {
1510 		if (!(flags & PIN_VALIDATE))
1511 			__i915_vma_pin(vma);
1512 		goto err_unlock;
1513 	}
1514 
1515 	err = i915_active_acquire(&vma->active);
1516 	if (err)
1517 		goto err_unlock;
1518 
1519 	if (!(bound & I915_VMA_BIND_MASK)) {
1520 		err = i915_vma_insert(vma, ww, size, alignment, flags);
1521 		if (err)
1522 			goto err_active;
1523 
1524 		if (i915_is_ggtt(vma->vm))
1525 			__i915_vma_set_map_and_fenceable(vma);
1526 	}
1527 
1528 	GEM_BUG_ON(!vma->pages);
1529 	err = i915_vma_bind(vma,
1530 			    vma->obj->pat_index,
1531 			    flags, work, vma_res);
1532 	vma_res = NULL;
1533 	if (err)
1534 		goto err_remove;
1535 
1536 	/* There should only be at most 2 active bindings (user, global) */
1537 	GEM_BUG_ON(bound + I915_VMA_PAGES_ACTIVE < bound);
1538 	atomic_add(I915_VMA_PAGES_ACTIVE, &vma->pages_count);
1539 	list_move_tail(&vma->vm_link, &vma->vm->bound_list);
1540 
1541 	if (!(flags & PIN_VALIDATE)) {
1542 		__i915_vma_pin(vma);
1543 		GEM_BUG_ON(!i915_vma_is_pinned(vma));
1544 	}
1545 	GEM_BUG_ON(!i915_vma_is_bound(vma, flags));
1546 	GEM_BUG_ON(i915_vma_misplaced(vma, size, alignment, flags));
1547 
1548 err_remove:
1549 	if (!i915_vma_is_bound(vma, I915_VMA_BIND_MASK)) {
1550 		i915_vma_detach(vma);
1551 		drm_mm_remove_node(&vma->node);
1552 	}
1553 err_active:
1554 	i915_active_release(&vma->active);
1555 err_unlock:
1556 	mutex_unlock(&vma->vm->mutex);
1557 err_vma_res:
1558 	i915_vma_resource_free(vma_res);
1559 err_fence:
1560 	if (work)
1561 		dma_fence_work_commit_imm(&work->base);
1562 err_rpm:
1563 	if (wakeref)
1564 		intel_runtime_pm_put(&vma->vm->i915->runtime_pm, wakeref);
1565 
1566 	if (moving)
1567 		dma_fence_put(moving);
1568 
1569 	i915_vma_put_pages(vma);
1570 	return err;
1571 }
1572 
1573 static void flush_idle_contexts(struct intel_gt *gt)
1574 {
1575 	struct intel_engine_cs *engine;
1576 	enum intel_engine_id id;
1577 
1578 	for_each_engine(engine, gt, id)
1579 		intel_engine_flush_barriers(engine);
1580 
1581 	intel_gt_wait_for_idle(gt, MAX_SCHEDULE_TIMEOUT);
1582 }
1583 
1584 static int __i915_ggtt_pin(struct i915_vma *vma, struct i915_gem_ww_ctx *ww,
1585 			   u32 align, unsigned int flags)
1586 {
1587 	struct i915_address_space *vm = vma->vm;
1588 	struct intel_gt *gt;
1589 	struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
1590 	int err;
1591 
1592 	do {
1593 		err = i915_vma_pin_ww(vma, ww, 0, align, flags | PIN_GLOBAL);
1594 
1595 		if (err != -ENOSPC) {
1596 			if (!err) {
1597 				err = i915_vma_wait_for_bind(vma);
1598 				if (err)
1599 					i915_vma_unpin(vma);
1600 			}
1601 			return err;
1602 		}
1603 
1604 		/* Unlike i915_vma_pin, we don't take no for an answer! */
1605 		list_for_each_entry(gt, &ggtt->gt_list, ggtt_link)
1606 			flush_idle_contexts(gt);
1607 		if (mutex_lock_interruptible(&vm->mutex) == 0) {
1608 			/*
1609 			 * We pass NULL ww here, as we don't want to unbind
1610 			 * locked objects when called from execbuf when pinning
1611 			 * is removed. This would probably regress badly.
1612 			 */
1613 			i915_gem_evict_vm(vm, NULL, NULL);
1614 			mutex_unlock(&vm->mutex);
1615 		}
1616 	} while (1);
1617 }
1618 
1619 int i915_ggtt_pin(struct i915_vma *vma, struct i915_gem_ww_ctx *ww,
1620 		  u32 align, unsigned int flags)
1621 {
1622 	struct i915_gem_ww_ctx _ww;
1623 	int err;
1624 
1625 	GEM_BUG_ON(!i915_vma_is_ggtt(vma));
1626 
1627 	if (ww)
1628 		return __i915_ggtt_pin(vma, ww, align, flags);
1629 
1630 	lockdep_assert_not_held(&vma->obj->base.resv->lock.base);
1631 
1632 	for_i915_gem_ww(&_ww, err, true) {
1633 		err = i915_gem_object_lock(vma->obj, &_ww);
1634 		if (!err)
1635 			err = __i915_ggtt_pin(vma, &_ww, align, flags);
1636 	}
1637 
1638 	return err;
1639 }
1640 
1641 /**
1642  * i915_ggtt_clear_scanout - Clear scanout flag for all objects ggtt vmas
1643  * @obj: i915 GEM object
1644  * This function clears scanout flags for objects ggtt vmas. These flags are set
1645  * when object is pinned for display use and this function to clear them all is
1646  * targeted to be called by frontbuffer tracking code when the frontbuffer is
1647  * about to be released.
1648  */
1649 void i915_ggtt_clear_scanout(struct drm_i915_gem_object *obj)
1650 {
1651 	struct i915_vma *vma;
1652 
1653 	spin_lock(&obj->vma.lock);
1654 	for_each_ggtt_vma(vma, obj) {
1655 		i915_vma_clear_scanout(vma);
1656 		vma->display_alignment = I915_GTT_MIN_ALIGNMENT;
1657 	}
1658 	spin_unlock(&obj->vma.lock);
1659 }
1660 
1661 static void __vma_close(struct i915_vma *vma, struct intel_gt *gt)
1662 {
1663 	/*
1664 	 * We defer actually closing, unbinding and destroying the VMA until
1665 	 * the next idle point, or if the object is freed in the meantime. By
1666 	 * postponing the unbind, we allow for it to be resurrected by the
1667 	 * client, avoiding the work required to rebind the VMA. This is
1668 	 * advantageous for DRI, where the client/server pass objects
1669 	 * between themselves, temporarily opening a local VMA to the
1670 	 * object, and then closing it again. The same object is then reused
1671 	 * on the next frame (or two, depending on the depth of the swap queue)
1672 	 * causing us to rebind the VMA once more. This ends up being a lot
1673 	 * of wasted work for the steady state.
1674 	 */
1675 	GEM_BUG_ON(i915_vma_is_closed(vma));
1676 	list_add(&vma->closed_link, &gt->closed_vma);
1677 }
1678 
1679 void i915_vma_close(struct i915_vma *vma)
1680 {
1681 	struct intel_gt *gt = vma->vm->gt;
1682 	unsigned long flags;
1683 
1684 	if (i915_vma_is_ggtt(vma))
1685 		return;
1686 
1687 	GEM_BUG_ON(!atomic_read(&vma->open_count));
1688 	if (atomic_dec_and_lock_irqsave(&vma->open_count,
1689 					&gt->closed_lock,
1690 					flags)) {
1691 		__vma_close(vma, gt);
1692 		spin_unlock_irqrestore(&gt->closed_lock, flags);
1693 	}
1694 }
1695 
1696 static void __i915_vma_remove_closed(struct i915_vma *vma)
1697 {
1698 	list_del_init(&vma->closed_link);
1699 }
1700 
1701 void i915_vma_reopen(struct i915_vma *vma)
1702 {
1703 	struct intel_gt *gt = vma->vm->gt;
1704 
1705 	spin_lock_irq(&gt->closed_lock);
1706 	if (i915_vma_is_closed(vma))
1707 		__i915_vma_remove_closed(vma);
1708 	spin_unlock_irq(&gt->closed_lock);
1709 }
1710 
1711 static void force_unbind(struct i915_vma *vma)
1712 {
1713 	if (!drm_mm_node_allocated(&vma->node))
1714 		return;
1715 
1716 	atomic_and(~I915_VMA_PIN_MASK, &vma->flags);
1717 	WARN_ON(__i915_vma_unbind(vma));
1718 	GEM_BUG_ON(drm_mm_node_allocated(&vma->node));
1719 }
1720 
1721 static void release_references(struct i915_vma *vma, struct intel_gt *gt,
1722 			       bool vm_ddestroy)
1723 {
1724 	struct drm_i915_gem_object *obj = vma->obj;
1725 
1726 	GEM_BUG_ON(i915_vma_is_active(vma));
1727 
1728 	spin_lock(&obj->vma.lock);
1729 	list_del(&vma->obj_link);
1730 	if (!RB_EMPTY_NODE(&vma->obj_node))
1731 		rb_erase(&vma->obj_node, &obj->vma.tree);
1732 
1733 	spin_unlock(&obj->vma.lock);
1734 
1735 	spin_lock_irq(&gt->closed_lock);
1736 	__i915_vma_remove_closed(vma);
1737 	spin_unlock_irq(&gt->closed_lock);
1738 
1739 	if (vm_ddestroy)
1740 		i915_vm_resv_put(vma->vm);
1741 
1742 	/* Wait for async active retire */
1743 	i915_active_wait(&vma->active);
1744 	i915_active_fini(&vma->active);
1745 	GEM_WARN_ON(vma->resource);
1746 	i915_vma_free(vma);
1747 }
1748 
1749 /*
1750  * i915_vma_destroy_locked - Remove all weak reference to the vma and put
1751  * the initial reference.
1752  *
1753  * This function should be called when it's decided the vma isn't needed
1754  * anymore. The caller must assure that it doesn't race with another lookup
1755  * plus destroy, typically by taking an appropriate reference.
1756  *
1757  * Current callsites are
1758  * - __i915_gem_object_pages_fini()
1759  * - __i915_vm_close() - Blocks the above function by taking a reference on
1760  * the object.
1761  * - __i915_vma_parked() - Blocks the above functions by taking a reference
1762  * on the vm and a reference on the object. Also takes the object lock so
1763  * destruction from __i915_vma_parked() can be blocked by holding the
1764  * object lock. Since the object lock is only allowed from within i915 with
1765  * an object refcount, holding the object lock also implicitly blocks the
1766  * vma freeing from __i915_gem_object_pages_fini().
1767  *
1768  * Because of locks taken during destruction, a vma is also guaranteed to
1769  * stay alive while the following locks are held if it was looked up while
1770  * holding one of the locks:
1771  * - vm->mutex
1772  * - obj->vma.lock
1773  * - gt->closed_lock
1774  */
1775 void i915_vma_destroy_locked(struct i915_vma *vma)
1776 {
1777 	lockdep_assert_held(&vma->vm->mutex);
1778 
1779 	force_unbind(vma);
1780 	list_del_init(&vma->vm_link);
1781 	release_references(vma, vma->vm->gt, false);
1782 }
1783 
1784 void i915_vma_destroy(struct i915_vma *vma)
1785 {
1786 	struct intel_gt *gt;
1787 	bool vm_ddestroy;
1788 
1789 	mutex_lock(&vma->vm->mutex);
1790 	force_unbind(vma);
1791 	list_del_init(&vma->vm_link);
1792 	vm_ddestroy = vma->vm_ddestroy;
1793 	vma->vm_ddestroy = false;
1794 
1795 	/* vma->vm may be freed when releasing vma->vm->mutex. */
1796 	gt = vma->vm->gt;
1797 	mutex_unlock(&vma->vm->mutex);
1798 	release_references(vma, gt, vm_ddestroy);
1799 }
1800 
1801 void i915_vma_parked(struct intel_gt *gt)
1802 {
1803 	struct i915_vma *vma, *next;
1804 	LIST_HEAD(closed);
1805 
1806 	spin_lock_irq(&gt->closed_lock);
1807 	list_for_each_entry_safe(vma, next, &gt->closed_vma, closed_link) {
1808 		struct drm_i915_gem_object *obj = vma->obj;
1809 		struct i915_address_space *vm = vma->vm;
1810 
1811 		/* XXX All to avoid keeping a reference on i915_vma itself */
1812 
1813 		if (!kref_get_unless_zero(&obj->base.refcount))
1814 			continue;
1815 
1816 		if (!i915_vm_tryget(vm)) {
1817 			i915_gem_object_put(obj);
1818 			continue;
1819 		}
1820 
1821 		list_move(&vma->closed_link, &closed);
1822 	}
1823 	spin_unlock_irq(&gt->closed_lock);
1824 
1825 	/* As the GT is held idle, no vma can be reopened as we destroy them */
1826 	list_for_each_entry_safe(vma, next, &closed, closed_link) {
1827 		struct drm_i915_gem_object *obj = vma->obj;
1828 		struct i915_address_space *vm = vma->vm;
1829 
1830 		if (i915_gem_object_trylock(obj, NULL)) {
1831 			INIT_LIST_HEAD(&vma->closed_link);
1832 			i915_vma_destroy(vma);
1833 			i915_gem_object_unlock(obj);
1834 		} else {
1835 			/* back you go.. */
1836 			spin_lock_irq(&gt->closed_lock);
1837 			list_add(&vma->closed_link, &gt->closed_vma);
1838 			spin_unlock_irq(&gt->closed_lock);
1839 		}
1840 
1841 		i915_gem_object_put(obj);
1842 		i915_vm_put(vm);
1843 	}
1844 }
1845 
1846 static void __i915_vma_iounmap(struct i915_vma *vma)
1847 {
1848 	GEM_BUG_ON(i915_vma_is_pinned(vma));
1849 
1850 	if (vma->iomap == NULL)
1851 		return;
1852 
1853 	if (page_unmask_bits(vma->iomap))
1854 		__i915_gem_object_release_map(vma->obj);
1855 	else
1856 		io_mapping_unmap(vma->iomap);
1857 	vma->iomap = NULL;
1858 }
1859 
1860 void i915_vma_revoke_mmap(struct i915_vma *vma)
1861 {
1862 	struct drm_vma_offset_node *node;
1863 	u64 vma_offset;
1864 
1865 	if (!i915_vma_has_userfault(vma))
1866 		return;
1867 
1868 	GEM_BUG_ON(!i915_vma_is_map_and_fenceable(vma));
1869 	GEM_BUG_ON(!vma->obj->userfault_count);
1870 
1871 	node = &vma->mmo->vma_node;
1872 	vma_offset = vma->gtt_view.partial.offset << PAGE_SHIFT;
1873 	unmap_mapping_range(vma->vm->i915->drm.anon_inode->i_mapping,
1874 			    drm_vma_node_offset_addr(node) + vma_offset,
1875 			    vma->size,
1876 			    1);
1877 
1878 	i915_vma_unset_userfault(vma);
1879 	if (!--vma->obj->userfault_count)
1880 		list_del(&vma->obj->userfault_link);
1881 }
1882 
1883 static int
1884 __i915_request_await_bind(struct i915_request *rq, struct i915_vma *vma)
1885 {
1886 	return __i915_request_await_exclusive(rq, &vma->active);
1887 }
1888 
1889 static int __i915_vma_move_to_active(struct i915_vma *vma, struct i915_request *rq)
1890 {
1891 	int err;
1892 
1893 	/* Wait for the vma to be bound before we start! */
1894 	err = __i915_request_await_bind(rq, vma);
1895 	if (err)
1896 		return err;
1897 
1898 	return i915_active_add_request(&vma->active, rq);
1899 }
1900 
1901 int _i915_vma_move_to_active(struct i915_vma *vma,
1902 			     struct i915_request *rq,
1903 			     struct dma_fence *fence,
1904 			     unsigned int flags)
1905 {
1906 	struct drm_i915_gem_object *obj = vma->obj;
1907 	int err;
1908 
1909 	assert_object_held(obj);
1910 
1911 	GEM_BUG_ON(!vma->pages);
1912 
1913 	if (!(flags & __EXEC_OBJECT_NO_REQUEST_AWAIT)) {
1914 		err = i915_request_await_object(rq, vma->obj, flags & EXEC_OBJECT_WRITE);
1915 		if (unlikely(err))
1916 			return err;
1917 	}
1918 	err = __i915_vma_move_to_active(vma, rq);
1919 	if (unlikely(err))
1920 		return err;
1921 
1922 	/*
1923 	 * Reserve fences slot early to prevent an allocation after preparing
1924 	 * the workload and associating fences with dma_resv.
1925 	 */
1926 	if (fence && !(flags & __EXEC_OBJECT_NO_RESERVE)) {
1927 		struct dma_fence *curr;
1928 		int idx;
1929 
1930 		dma_fence_array_for_each(curr, idx, fence)
1931 			;
1932 		err = dma_resv_reserve_fences(vma->obj->base.resv, idx);
1933 		if (unlikely(err))
1934 			return err;
1935 	}
1936 
1937 	if (flags & EXEC_OBJECT_WRITE) {
1938 		struct intel_frontbuffer *front;
1939 
1940 		front = i915_gem_object_get_frontbuffer(obj);
1941 		if (unlikely(front)) {
1942 			if (intel_frontbuffer_invalidate(front, ORIGIN_CS))
1943 				i915_active_add_request(&front->write, rq);
1944 			intel_frontbuffer_put(front);
1945 		}
1946 	}
1947 
1948 	if (fence) {
1949 		struct dma_fence *curr;
1950 		enum dma_resv_usage usage;
1951 		int idx;
1952 
1953 		if (flags & EXEC_OBJECT_WRITE) {
1954 			usage = DMA_RESV_USAGE_WRITE;
1955 			obj->write_domain = I915_GEM_DOMAIN_RENDER;
1956 			obj->read_domains = 0;
1957 		} else {
1958 			usage = DMA_RESV_USAGE_READ;
1959 			obj->write_domain = 0;
1960 		}
1961 
1962 		dma_fence_array_for_each(curr, idx, fence)
1963 			dma_resv_add_fence(vma->obj->base.resv, curr, usage);
1964 	}
1965 
1966 	if (flags & EXEC_OBJECT_NEEDS_FENCE && vma->fence)
1967 		i915_active_add_request(&vma->fence->active, rq);
1968 
1969 	obj->read_domains |= I915_GEM_GPU_DOMAINS;
1970 	obj->mm.dirty = true;
1971 
1972 	GEM_BUG_ON(!i915_vma_is_active(vma));
1973 	return 0;
1974 }
1975 
1976 struct dma_fence *__i915_vma_evict(struct i915_vma *vma, bool async)
1977 {
1978 	struct i915_vma_resource *vma_res = vma->resource;
1979 	struct dma_fence *unbind_fence;
1980 
1981 	GEM_BUG_ON(i915_vma_is_pinned(vma));
1982 	assert_vma_held_evict(vma);
1983 
1984 	if (i915_vma_is_map_and_fenceable(vma)) {
1985 		/* Force a pagefault for domain tracking on next user access */
1986 		i915_vma_revoke_mmap(vma);
1987 
1988 		/*
1989 		 * Check that we have flushed all writes through the GGTT
1990 		 * before the unbind, other due to non-strict nature of those
1991 		 * indirect writes they may end up referencing the GGTT PTE
1992 		 * after the unbind.
1993 		 *
1994 		 * Note that we may be concurrently poking at the GGTT_WRITE
1995 		 * bit from set-domain, as we mark all GGTT vma associated
1996 		 * with an object. We know this is for another vma, as we
1997 		 * are currently unbinding this one -- so if this vma will be
1998 		 * reused, it will be refaulted and have its dirty bit set
1999 		 * before the next write.
2000 		 */
2001 		i915_vma_flush_writes(vma);
2002 
2003 		/* release the fence reg _after_ flushing */
2004 		i915_vma_revoke_fence(vma);
2005 
2006 		clear_bit(I915_VMA_CAN_FENCE_BIT, __i915_vma_flags(vma));
2007 	}
2008 
2009 	__i915_vma_iounmap(vma);
2010 
2011 	GEM_BUG_ON(vma->fence);
2012 	GEM_BUG_ON(i915_vma_has_userfault(vma));
2013 
2014 	/* Object backend must be async capable. */
2015 	GEM_WARN_ON(async && !vma->resource->bi.pages_rsgt);
2016 
2017 	/* If vm is not open, unbind is a nop. */
2018 	vma_res->needs_wakeref = i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND) &&
2019 		kref_read(&vma->vm->ref);
2020 	vma_res->skip_pte_rewrite = !kref_read(&vma->vm->ref) ||
2021 		vma->vm->skip_pte_rewrite;
2022 	trace_i915_vma_unbind(vma);
2023 
2024 	if (async)
2025 		unbind_fence = i915_vma_resource_unbind(vma_res,
2026 							vma->obj->mm.tlb);
2027 	else
2028 		unbind_fence = i915_vma_resource_unbind(vma_res, NULL);
2029 
2030 	vma->resource = NULL;
2031 
2032 	atomic_and(~(I915_VMA_BIND_MASK | I915_VMA_ERROR | I915_VMA_GGTT_WRITE),
2033 		   &vma->flags);
2034 
2035 	i915_vma_detach(vma);
2036 
2037 	if (!async) {
2038 		if (unbind_fence) {
2039 			dma_fence_wait(unbind_fence, false);
2040 			dma_fence_put(unbind_fence);
2041 			unbind_fence = NULL;
2042 		}
2043 		vma_invalidate_tlb(vma->vm, vma->obj->mm.tlb);
2044 	}
2045 
2046 	/*
2047 	 * Binding itself may not have completed until the unbind fence signals,
2048 	 * so don't drop the pages until that happens, unless the resource is
2049 	 * async_capable.
2050 	 */
2051 
2052 	vma_unbind_pages(vma);
2053 	return unbind_fence;
2054 }
2055 
2056 int __i915_vma_unbind(struct i915_vma *vma)
2057 {
2058 	int ret;
2059 
2060 	lockdep_assert_held(&vma->vm->mutex);
2061 	assert_vma_held_evict(vma);
2062 
2063 	if (!drm_mm_node_allocated(&vma->node))
2064 		return 0;
2065 
2066 	if (i915_vma_is_pinned(vma)) {
2067 		vma_print_allocator(vma, "is pinned");
2068 		return -EAGAIN;
2069 	}
2070 
2071 	/*
2072 	 * After confirming that no one else is pinning this vma, wait for
2073 	 * any laggards who may have crept in during the wait (through
2074 	 * a residual pin skipping the vm->mutex) to complete.
2075 	 */
2076 	ret = i915_vma_sync(vma);
2077 	if (ret)
2078 		return ret;
2079 
2080 	GEM_BUG_ON(i915_vma_is_active(vma));
2081 	__i915_vma_evict(vma, false);
2082 
2083 	drm_mm_remove_node(&vma->node); /* pairs with i915_vma_release() */
2084 	return 0;
2085 }
2086 
2087 static struct dma_fence *__i915_vma_unbind_async(struct i915_vma *vma)
2088 {
2089 	struct dma_fence *fence;
2090 
2091 	lockdep_assert_held(&vma->vm->mutex);
2092 
2093 	if (!drm_mm_node_allocated(&vma->node))
2094 		return NULL;
2095 
2096 	if (i915_vma_is_pinned(vma) ||
2097 	    &vma->obj->mm.rsgt->table != vma->resource->bi.pages)
2098 		return ERR_PTR(-EAGAIN);
2099 
2100 	/*
2101 	 * We probably need to replace this with awaiting the fences of the
2102 	 * object's dma_resv when the vma active goes away. When doing that
2103 	 * we need to be careful to not add the vma_resource unbind fence
2104 	 * immediately to the object's dma_resv, because then unbinding
2105 	 * the next vma from the object, in case there are many, will
2106 	 * actually await the unbinding of the previous vmas, which is
2107 	 * undesirable.
2108 	 */
2109 	if (i915_sw_fence_await_active(&vma->resource->chain, &vma->active,
2110 				       I915_ACTIVE_AWAIT_EXCL |
2111 				       I915_ACTIVE_AWAIT_ACTIVE) < 0) {
2112 		return ERR_PTR(-EBUSY);
2113 	}
2114 
2115 	fence = __i915_vma_evict(vma, true);
2116 
2117 	drm_mm_remove_node(&vma->node); /* pairs with i915_vma_release() */
2118 
2119 	return fence;
2120 }
2121 
2122 int i915_vma_unbind(struct i915_vma *vma)
2123 {
2124 	struct i915_address_space *vm = vma->vm;
2125 	intel_wakeref_t wakeref = 0;
2126 	int err;
2127 
2128 	assert_object_held_shared(vma->obj);
2129 
2130 	/* Optimistic wait before taking the mutex */
2131 	err = i915_vma_sync(vma);
2132 	if (err)
2133 		return err;
2134 
2135 	if (!drm_mm_node_allocated(&vma->node))
2136 		return 0;
2137 
2138 	if (i915_vma_is_pinned(vma)) {
2139 		vma_print_allocator(vma, "is pinned");
2140 		return -EAGAIN;
2141 	}
2142 
2143 	if (i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND))
2144 		/* XXX not always required: nop_clear_range */
2145 		wakeref = intel_runtime_pm_get(&vm->i915->runtime_pm);
2146 
2147 	err = mutex_lock_interruptible_nested(&vma->vm->mutex, !wakeref);
2148 	if (err)
2149 		goto out_rpm;
2150 
2151 	err = __i915_vma_unbind(vma);
2152 	mutex_unlock(&vm->mutex);
2153 
2154 out_rpm:
2155 	if (wakeref)
2156 		intel_runtime_pm_put(&vm->i915->runtime_pm, wakeref);
2157 	return err;
2158 }
2159 
2160 int i915_vma_unbind_async(struct i915_vma *vma, bool trylock_vm)
2161 {
2162 	struct drm_i915_gem_object *obj = vma->obj;
2163 	struct i915_address_space *vm = vma->vm;
2164 	intel_wakeref_t wakeref = 0;
2165 	struct dma_fence *fence;
2166 	int err;
2167 
2168 	/*
2169 	 * We need the dma-resv lock since we add the
2170 	 * unbind fence to the dma-resv object.
2171 	 */
2172 	assert_object_held(obj);
2173 
2174 	if (!drm_mm_node_allocated(&vma->node))
2175 		return 0;
2176 
2177 	if (i915_vma_is_pinned(vma)) {
2178 		vma_print_allocator(vma, "is pinned");
2179 		return -EAGAIN;
2180 	}
2181 
2182 	if (!obj->mm.rsgt)
2183 		return -EBUSY;
2184 
2185 	err = dma_resv_reserve_fences(obj->base.resv, 2);
2186 	if (err)
2187 		return -EBUSY;
2188 
2189 	/*
2190 	 * It would be great if we could grab this wakeref from the
2191 	 * async unbind work if needed, but we can't because it uses
2192 	 * kmalloc and it's in the dma-fence signalling critical path.
2193 	 */
2194 	if (i915_vma_is_bound(vma, I915_VMA_GLOBAL_BIND))
2195 		wakeref = intel_runtime_pm_get(&vm->i915->runtime_pm);
2196 
2197 	if (trylock_vm && !mutex_trylock(&vm->mutex)) {
2198 		err = -EBUSY;
2199 		goto out_rpm;
2200 	} else if (!trylock_vm) {
2201 		err = mutex_lock_interruptible_nested(&vm->mutex, !wakeref);
2202 		if (err)
2203 			goto out_rpm;
2204 	}
2205 
2206 	fence = __i915_vma_unbind_async(vma);
2207 	mutex_unlock(&vm->mutex);
2208 	if (IS_ERR_OR_NULL(fence)) {
2209 		err = PTR_ERR_OR_ZERO(fence);
2210 		goto out_rpm;
2211 	}
2212 
2213 	dma_resv_add_fence(obj->base.resv, fence, DMA_RESV_USAGE_READ);
2214 	dma_fence_put(fence);
2215 
2216 out_rpm:
2217 	if (wakeref)
2218 		intel_runtime_pm_put(&vm->i915->runtime_pm, wakeref);
2219 	return err;
2220 }
2221 
2222 int i915_vma_unbind_unlocked(struct i915_vma *vma)
2223 {
2224 	int err;
2225 
2226 	i915_gem_object_lock(vma->obj, NULL);
2227 	err = i915_vma_unbind(vma);
2228 	i915_gem_object_unlock(vma->obj);
2229 
2230 	return err;
2231 }
2232 
2233 struct i915_vma *i915_vma_make_unshrinkable(struct i915_vma *vma)
2234 {
2235 	i915_gem_object_make_unshrinkable(vma->obj);
2236 	return vma;
2237 }
2238 
2239 void i915_vma_make_shrinkable(struct i915_vma *vma)
2240 {
2241 	i915_gem_object_make_shrinkable(vma->obj);
2242 }
2243 
2244 void i915_vma_make_purgeable(struct i915_vma *vma)
2245 {
2246 	i915_gem_object_make_purgeable(vma->obj);
2247 }
2248 
2249 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
2250 #include "selftests/i915_vma.c"
2251 #endif
2252 
2253 void i915_vma_module_exit(void)
2254 {
2255 	kmem_cache_destroy(slab_vmas);
2256 }
2257 
2258 int __init i915_vma_module_init(void)
2259 {
2260 	slab_vmas = KMEM_CACHE(i915_vma, SLAB_HWCACHE_ALIGN);
2261 	if (!slab_vmas)
2262 		return -ENOMEM;
2263 
2264 	return 0;
2265 }
2266