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path: root/drivers/gpu/drm/i915/i915_vma.c
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Diffstat (limited to 'drivers/gpu/drm/i915/i915_vma.c')
-rw-r--r--drivers/gpu/drm/i915/i915_vma.c706
1 files changed, 706 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
new file mode 100644
index 000000000000..df20e9bc1c0f
--- /dev/null
+++ b/drivers/gpu/drm/i915/i915_vma.c
@@ -0,0 +1,706 @@
+/*
+ * Copyright © 2016 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ */
+
+#include "i915_vma.h"
+
+#include "i915_drv.h"
+#include "intel_ringbuffer.h"
+#include "intel_frontbuffer.h"
+
+#include <drm/drm_gem.h>
+
+static void
+i915_vma_retire(struct i915_gem_active *active,
+ struct drm_i915_gem_request *rq)
+{
+ const unsigned int idx = rq->engine->id;
+ struct i915_vma *vma =
+ container_of(active, struct i915_vma, last_read[idx]);
+ struct drm_i915_gem_object *obj = vma->obj;
+
+ GEM_BUG_ON(!i915_vma_has_active_engine(vma, idx));
+
+ i915_vma_clear_active(vma, idx);
+ if (i915_vma_is_active(vma))
+ return;
+
+ GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
+ list_move_tail(&vma->vm_link, &vma->vm->inactive_list);
+ if (unlikely(i915_vma_is_closed(vma) && !i915_vma_is_pinned(vma)))
+ WARN_ON(i915_vma_unbind(vma));
+
+ GEM_BUG_ON(!i915_gem_object_is_active(obj));
+ if (--obj->active_count)
+ return;
+
+ /* Bump our place on the bound list to keep it roughly in LRU order
+ * so that we don't steal from recently used but inactive objects
+ * (unless we are forced to ofc!)
+ */
+ if (obj->bind_count)
+ list_move_tail(&obj->global_link, &rq->i915->mm.bound_list);
+
+ obj->mm.dirty = true; /* be paranoid */
+
+ if (i915_gem_object_has_active_reference(obj)) {
+ i915_gem_object_clear_active_reference(obj);
+ i915_gem_object_put(obj);
+ }
+}
+
+static struct i915_vma *
+vma_create(struct drm_i915_gem_object *obj,
+ struct i915_address_space *vm,
+ const struct i915_ggtt_view *view)
+{
+ struct i915_vma *vma;
+ struct rb_node *rb, **p;
+ int i;
+
+ vma = kmem_cache_zalloc(vm->i915->vmas, GFP_KERNEL);
+ if (vma == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ INIT_LIST_HEAD(&vma->exec_list);
+ for (i = 0; i < ARRAY_SIZE(vma->last_read); i++)
+ init_request_active(&vma->last_read[i], i915_vma_retire);
+ init_request_active(&vma->last_fence, NULL);
+ vma->vm = vm;
+ vma->obj = obj;
+ vma->size = obj->base.size;
+ vma->display_alignment = I915_GTT_MIN_ALIGNMENT;
+
+ if (view && view->type != I915_GGTT_VIEW_NORMAL) {
+ vma->ggtt_view = *view;
+ if (view->type == I915_GGTT_VIEW_PARTIAL) {
+ GEM_BUG_ON(range_overflows_t(u64,
+ view->partial.offset,
+ view->partial.size,
+ obj->base.size >> PAGE_SHIFT));
+ vma->size = view->partial.size;
+ vma->size <<= PAGE_SHIFT;
+ GEM_BUG_ON(vma->size >= obj->base.size);
+ } else if (view->type == I915_GGTT_VIEW_ROTATED) {
+ vma->size = intel_rotation_info_size(&view->rotated);
+ vma->size <<= PAGE_SHIFT;
+ }
+ }
+
+ if (unlikely(vma->size > vm->total))
+ goto err_vma;
+
+ GEM_BUG_ON(!IS_ALIGNED(vma->size, I915_GTT_PAGE_SIZE));
+
+ if (i915_is_ggtt(vm)) {
+ if (unlikely(overflows_type(vma->size, u32)))
+ goto err_vma;
+
+ vma->fence_size = i915_gem_fence_size(vm->i915, vma->size,
+ i915_gem_object_get_tiling(obj),
+ i915_gem_object_get_stride(obj));
+ if (unlikely(vma->fence_size < vma->size || /* overflow */
+ vma->fence_size > vm->total))
+ goto err_vma;
+
+ GEM_BUG_ON(!IS_ALIGNED(vma->fence_size, I915_GTT_MIN_ALIGNMENT));
+
+ vma->fence_alignment = i915_gem_fence_alignment(vm->i915, vma->size,
+ i915_gem_object_get_tiling(obj),
+ i915_gem_object_get_stride(obj));
+ GEM_BUG_ON(!is_power_of_2(vma->fence_alignment));
+
+ vma->flags |= I915_VMA_GGTT;
+ list_add(&vma->obj_link, &obj->vma_list);
+ } else {
+ i915_ppgtt_get(i915_vm_to_ppgtt(vm));
+ list_add_tail(&vma->obj_link, &obj->vma_list);
+ }
+
+ rb = NULL;
+ p = &obj->vma_tree.rb_node;
+ while (*p) {
+ struct i915_vma *pos;
+
+ rb = *p;
+ pos = rb_entry(rb, struct i915_vma, obj_node);
+ if (i915_vma_compare(pos, vm, view) < 0)
+ p = &rb->rb_right;
+ else
+ p = &rb->rb_left;
+ }
+ rb_link_node(&vma->obj_node, rb, p);
+ rb_insert_color(&vma->obj_node, &obj->vma_tree);
+ list_add(&vma->vm_link, &vm->unbound_list);
+
+ return vma;
+
+err_vma:
+ kmem_cache_free(vm->i915->vmas, vma);
+ return ERR_PTR(-E2BIG);
+}
+
+static struct i915_vma *
+vma_lookup(struct drm_i915_gem_object *obj,
+ struct i915_address_space *vm,
+ const struct i915_ggtt_view *view)
+{
+ struct rb_node *rb;
+
+ rb = obj->vma_tree.rb_node;
+ while (rb) {
+ struct i915_vma *vma = rb_entry(rb, struct i915_vma, obj_node);
+ long cmp;
+
+ cmp = i915_vma_compare(vma, vm, view);
+ if (cmp == 0)
+ return vma;
+
+ if (cmp < 0)
+ rb = rb->rb_right;
+ else
+ rb = rb->rb_left;
+ }
+
+ return NULL;
+}
+
+/**
+ * i915_vma_instance - return the singleton instance of the VMA
+ * @obj: parent &struct drm_i915_gem_object to be mapped
+ * @vm: address space in which the mapping is located
+ * @view: additional mapping requirements
+ *
+ * i915_vma_instance() looks up an existing VMA of the @obj in the @vm with
+ * the same @view characteristics. If a match is not found, one is created.
+ * Once created, the VMA is kept until either the object is freed, or the
+ * address space is closed.
+ *
+ * Must be called with struct_mutex held.
+ *
+ * Returns the vma, or an error pointer.
+ */
+struct i915_vma *
+i915_vma_instance(struct drm_i915_gem_object *obj,
+ struct i915_address_space *vm,
+ const struct i915_ggtt_view *view)
+{
+ struct i915_vma *vma;
+
+ lockdep_assert_held(&obj->base.dev->struct_mutex);
+ GEM_BUG_ON(view && !i915_is_ggtt(vm));
+ GEM_BUG_ON(vm->closed);
+
+ vma = vma_lookup(obj, vm, view);
+ if (!vma)
+ vma = vma_create(obj, vm, view);
+
+ GEM_BUG_ON(!IS_ERR(vma) && i915_vma_is_closed(vma));
+ GEM_BUG_ON(!IS_ERR(vma) && i915_vma_compare(vma, vm, view));
+ GEM_BUG_ON(!IS_ERR(vma) && vma_lookup(obj, vm, view) != vma);
+ return vma;
+}
+
+/**
+ * i915_vma_bind - Sets up PTEs for an VMA in it's corresponding address space.
+ * @vma: VMA to map
+ * @cache_level: mapping cache level
+ * @flags: flags like global or local mapping
+ *
+ * DMA addresses are taken from the scatter-gather table of this object (or of
+ * this VMA in case of non-default GGTT views) and PTE entries set up.
+ * Note that DMA addresses are also the only part of the SG table we care about.
+ */
+int i915_vma_bind(struct i915_vma *vma, enum i915_cache_level cache_level,
+ u32 flags)
+{
+ u32 bind_flags;
+ u32 vma_flags;
+ int ret;
+
+ if (WARN_ON(flags == 0))
+ return -EINVAL;
+
+ bind_flags = 0;
+ if (flags & PIN_GLOBAL)
+ bind_flags |= I915_VMA_GLOBAL_BIND;
+ if (flags & PIN_USER)
+ bind_flags |= I915_VMA_LOCAL_BIND;
+
+ vma_flags = vma->flags & (I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND);
+ if (flags & PIN_UPDATE)
+ bind_flags |= vma_flags;
+ else
+ bind_flags &= ~vma_flags;
+ if (bind_flags == 0)
+ return 0;
+
+ if (GEM_WARN_ON(range_overflows(vma->node.start,
+ vma->node.size,
+ vma->vm->total)))
+ return -ENODEV;
+
+ if (vma_flags == 0 && vma->vm->allocate_va_range) {
+ trace_i915_va_alloc(vma);
+ ret = vma->vm->allocate_va_range(vma->vm,
+ vma->node.start,
+ vma->node.size);
+ if (ret)
+ return ret;
+ }
+
+ trace_i915_vma_bind(vma, bind_flags);
+ ret = vma->vm->bind_vma(vma, cache_level, bind_flags);
+ if (ret)
+ return ret;
+
+ vma->flags |= bind_flags;
+ return 0;
+}
+
+void __iomem *i915_vma_pin_iomap(struct i915_vma *vma)
+{
+ void __iomem *ptr;
+
+ /* Access through the GTT requires the device to be awake. */
+ assert_rpm_wakelock_held(vma->vm->i915);
+
+ lockdep_assert_held(&vma->vm->i915->drm.struct_mutex);
+ if (WARN_ON(!i915_vma_is_map_and_fenceable(vma)))
+ return IO_ERR_PTR(-ENODEV);
+
+ GEM_BUG_ON(!i915_vma_is_ggtt(vma));
+ GEM_BUG_ON((vma->flags & I915_VMA_GLOBAL_BIND) == 0);
+
+ ptr = vma->iomap;
+ if (ptr == NULL) {
+ ptr = io_mapping_map_wc(&i915_vm_to_ggtt(vma->vm)->mappable,
+ vma->node.start,
+ vma->node.size);
+ if (ptr == NULL)
+ return IO_ERR_PTR(-ENOMEM);
+
+ vma->iomap = ptr;
+ }
+
+ __i915_vma_pin(vma);
+ return ptr;
+}
+
+void i915_vma_unpin_and_release(struct i915_vma **p_vma)
+{
+ struct i915_vma *vma;
+ struct drm_i915_gem_object *obj;
+
+ vma = fetch_and_zero(p_vma);
+ if (!vma)
+ return;
+
+ obj = vma->obj;
+
+ i915_vma_unpin(vma);
+ i915_vma_close(vma);
+
+ __i915_gem_object_release_unless_active(obj);
+}
+
+bool
+i915_vma_misplaced(struct i915_vma *vma, u64 size, u64 alignment, u64 flags)
+{
+ if (!drm_mm_node_allocated(&vma->node))
+ return false;
+
+ if (vma->node.size < size)
+ return true;
+
+ GEM_BUG_ON(alignment && !is_power_of_2(alignment));
+ if (alignment && !IS_ALIGNED(vma->node.start, alignment))
+ return true;
+
+ if (flags & PIN_MAPPABLE && !i915_vma_is_map_and_fenceable(vma))
+ return true;
+
+ if (flags & PIN_OFFSET_BIAS &&
+ vma->node.start < (flags & PIN_OFFSET_MASK))
+ return true;
+
+ if (flags & PIN_OFFSET_FIXED &&
+ vma->node.start != (flags & PIN_OFFSET_MASK))
+ return true;
+
+ return false;
+}
+
+void __i915_vma_set_map_and_fenceable(struct i915_vma *vma)
+{
+ bool mappable, fenceable;
+
+ GEM_BUG_ON(!i915_vma_is_ggtt(vma));
+ GEM_BUG_ON(!vma->fence_size);
+
+ /*
+ * Explicitly disable for rotated VMA since the display does not
+ * need the fence and the VMA is not accessible to other users.
+ */
+ if (vma->ggtt_view.type == I915_GGTT_VIEW_ROTATED)
+ return;
+
+ fenceable = (vma->node.size >= vma->fence_size &&
+ IS_ALIGNED(vma->node.start, vma->fence_alignment));
+
+ mappable = vma->node.start + vma->fence_size <= i915_vm_to_ggtt(vma->vm)->mappable_end;
+
+ if (mappable && fenceable)
+ vma->flags |= I915_VMA_CAN_FENCE;
+ else
+ vma->flags &= ~I915_VMA_CAN_FENCE;
+}
+
+static bool color_differs(struct drm_mm_node *node, unsigned long color)
+{
+ return node->allocated && node->color != color;
+}
+
+bool i915_gem_valid_gtt_space(struct i915_vma *vma, unsigned long cache_level)
+{
+ struct drm_mm_node *node = &vma->node;
+ struct drm_mm_node *other;
+
+ /*
+ * On some machines we have to be careful when putting differing types
+ * of snoopable memory together to avoid the prefetcher crossing memory
+ * domains and dying. During vm initialisation, we decide whether or not
+ * these constraints apply and set the drm_mm.color_adjust
+ * appropriately.
+ */
+ if (vma->vm->mm.color_adjust == NULL)
+ return true;
+
+ /* Only valid to be called on an already inserted vma */
+ GEM_BUG_ON(!drm_mm_node_allocated(node));
+ GEM_BUG_ON(list_empty(&node->node_list));
+
+ other = list_prev_entry(node, node_list);
+ if (color_differs(other, cache_level) && !drm_mm_hole_follows(other))
+ return false;
+
+ other = list_next_entry(node, node_list);
+ if (color_differs(other, cache_level) && !drm_mm_hole_follows(node))
+ return false;
+
+ return true;
+}
+
+/**
+ * i915_vma_insert - finds a slot for the vma in its address space
+ * @vma: the vma
+ * @size: requested size in bytes (can be larger than the VMA)
+ * @alignment: required alignment
+ * @flags: mask of PIN_* flags to use
+ *
+ * First we try to allocate some free space that meets the requirements for
+ * the VMA. Failiing that, if the flags permit, it will evict an old VMA,
+ * preferrably the oldest idle entry to make room for the new VMA.
+ *
+ * Returns:
+ * 0 on success, negative error code otherwise.
+ */
+static int
+i915_vma_insert(struct i915_vma *vma, u64 size, u64 alignment, u64 flags)
+{
+ struct drm_i915_private *dev_priv = vma->vm->i915;
+ struct drm_i915_gem_object *obj = vma->obj;
+ u64 start, end;
+ int ret;
+
+ GEM_BUG_ON(vma->flags & (I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND));
+ GEM_BUG_ON(drm_mm_node_allocated(&vma->node));
+
+ size = max(size, vma->size);
+ alignment = max(alignment, vma->display_alignment);
+ if (flags & PIN_MAPPABLE) {
+ size = max_t(typeof(size), size, vma->fence_size);
+ alignment = max_t(typeof(alignment),
+ alignment, vma->fence_alignment);
+ }
+
+ GEM_BUG_ON(!IS_ALIGNED(size, I915_GTT_PAGE_SIZE));
+ GEM_BUG_ON(!IS_ALIGNED(alignment, I915_GTT_MIN_ALIGNMENT));
+ GEM_BUG_ON(!is_power_of_2(alignment));
+
+ start = flags & PIN_OFFSET_BIAS ? flags & PIN_OFFSET_MASK : 0;
+ GEM_BUG_ON(!IS_ALIGNED(start, I915_GTT_PAGE_SIZE));
+
+ end = vma->vm->total;
+ if (flags & PIN_MAPPABLE)
+ end = min_t(u64, end, dev_priv->ggtt.mappable_end);
+ if (flags & PIN_ZONE_4G)
+ end = min_t(u64, end, (1ULL << 32) - I915_GTT_PAGE_SIZE);
+ GEM_BUG_ON(!IS_ALIGNED(end, I915_GTT_PAGE_SIZE));
+
+ /* If binding the object/GGTT view requires more space than the entire
+ * aperture has, reject it early before evicting everything in a vain
+ * attempt to find space.
+ */
+ if (size > end) {
+ DRM_DEBUG("Attempting to bind an object larger than the aperture: request=%llu [object=%zd] > %s aperture=%llu\n",
+ size, obj->base.size,
+ flags & PIN_MAPPABLE ? "mappable" : "total",
+ end);
+ return -E2BIG;
+ }
+
+ ret = i915_gem_object_pin_pages(obj);
+ if (ret)
+ return ret;
+
+ if (flags & PIN_OFFSET_FIXED) {
+ u64 offset = flags & PIN_OFFSET_MASK;
+ if (!IS_ALIGNED(offset, alignment) ||
+ range_overflows(offset, size, end)) {
+ ret = -EINVAL;
+ goto err_unpin;
+ }
+
+ ret = i915_gem_gtt_reserve(vma->vm, &vma->node,
+ size, offset, obj->cache_level,
+ flags);
+ if (ret)
+ goto err_unpin;
+ } else {
+ ret = i915_gem_gtt_insert(vma->vm, &vma->node,
+ size, alignment, obj->cache_level,
+ start, end, flags);
+ if (ret)
+ goto err_unpin;
+
+ GEM_BUG_ON(vma->node.start < start);
+ GEM_BUG_ON(vma->node.start + vma->node.size > end);
+ }
+ GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
+ GEM_BUG_ON(!i915_gem_valid_gtt_space(vma, obj->cache_level));
+
+ list_move_tail(&obj->global_link, &dev_priv->mm.bound_list);
+ list_move_tail(&vma->vm_link, &vma->vm->inactive_list);
+ obj->bind_count++;
+ GEM_BUG_ON(atomic_read(&obj->mm.pages_pin_count) < obj->bind_count);
+
+ return 0;
+
+err_unpin:
+ i915_gem_object_unpin_pages(obj);
+ return ret;
+}
+
+static void
+i915_vma_remove(struct i915_vma *vma)
+{
+ struct drm_i915_gem_object *obj = vma->obj;
+
+ GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
+ GEM_BUG_ON(vma->flags & (I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND));
+
+ drm_mm_remove_node(&vma->node);
+ list_move_tail(&vma->vm_link, &vma->vm->unbound_list);
+
+ /* Since the unbound list is global, only move to that list if
+ * no more VMAs exist.
+ */
+ if (--obj->bind_count == 0)
+ list_move_tail(&obj->global_link,
+ &to_i915(obj->base.dev)->mm.unbound_list);
+
+ /* And finally now the object is completely decoupled from this vma,
+ * we can drop its hold on the backing storage and allow it to be
+ * reaped by the shrinker.
+ */
+ i915_gem_object_unpin_pages(obj);
+ GEM_BUG_ON(atomic_read(&obj->mm.pages_pin_count) < obj->bind_count);
+}
+
+int __i915_vma_do_pin(struct i915_vma *vma,
+ u64 size, u64 alignment, u64 flags)
+{
+ const unsigned int bound = vma->flags;
+ int ret;
+
+ lockdep_assert_held(&vma->vm->i915->drm.struct_mutex);
+ GEM_BUG_ON((flags & (PIN_GLOBAL | PIN_USER)) == 0);
+ GEM_BUG_ON((flags & PIN_GLOBAL) && !i915_vma_is_ggtt(vma));
+
+ if (WARN_ON(bound & I915_VMA_PIN_OVERFLOW)) {
+ ret = -EBUSY;
+ goto err_unpin;
+ }
+
+ if ((bound & I915_VMA_BIND_MASK) == 0) {
+ ret = i915_vma_insert(vma, size, alignment, flags);
+ if (ret)
+ goto err_unpin;
+ }
+
+ ret = i915_vma_bind(vma, vma->obj->cache_level, flags);
+ if (ret)
+ goto err_remove;
+
+ if ((bound ^ vma->flags) & I915_VMA_GLOBAL_BIND)
+ __i915_vma_set_map_and_fenceable(vma);
+
+ GEM_BUG_ON(!drm_mm_node_allocated(&vma->node));
+ GEM_BUG_ON(i915_vma_misplaced(vma, size, alignment, flags));
+ return 0;
+
+err_remove:
+ if ((bound & I915_VMA_BIND_MASK) == 0) {
+ GEM_BUG_ON(vma->pages);
+ i915_vma_remove(vma);
+ }
+err_unpin:
+ __i915_vma_unpin(vma);
+ return ret;
+}
+
+void i915_vma_destroy(struct i915_vma *vma)
+{
+ GEM_BUG_ON(vma->node.allocated);
+ GEM_BUG_ON(i915_vma_is_active(vma));
+ GEM_BUG_ON(!i915_vma_is_closed(vma));
+ GEM_BUG_ON(vma->fence);
+
+ list_del(&vma->vm_link);
+ if (!i915_vma_is_ggtt(vma))
+ i915_ppgtt_put(i915_vm_to_ppgtt(vma->vm));
+
+ kmem_cache_free(to_i915(vma->obj->base.dev)->vmas, vma);
+}
+
+void i915_vma_close(struct i915_vma *vma)
+{
+ GEM_BUG_ON(i915_vma_is_closed(vma));
+ vma->flags |= I915_VMA_CLOSED;
+
+ list_del(&vma->obj_link);
+ rb_erase(&vma->obj_node, &vma->obj->vma_tree);
+
+ if (!i915_vma_is_active(vma) && !i915_vma_is_pinned(vma))
+ WARN_ON(i915_vma_unbind(vma));
+}
+
+static void __i915_vma_iounmap(struct i915_vma *vma)
+{
+ GEM_BUG_ON(i915_vma_is_pinned(vma));
+
+ if (vma->iomap == NULL)
+ return;
+
+ io_mapping_unmap(vma->iomap);
+ vma->iomap = NULL;
+}
+
+int i915_vma_unbind(struct i915_vma *vma)
+{
+ struct drm_i915_gem_object *obj = vma->obj;
+ unsigned long active;
+ int ret;
+
+ lockdep_assert_held(&obj->base.dev->struct_mutex);
+
+ /* First wait upon any activity as retiring the request may
+ * have side-effects such as unpinning or even unbinding this vma.
+ */
+ active = i915_vma_get_active(vma);
+ if (active) {
+ int idx;
+
+ /* When a closed VMA is retired, it is unbound - eek.
+ * In order to prevent it from being recursively closed,
+ * take a pin on the vma so that the second unbind is
+ * aborted.
+ *
+ * Even more scary is that the retire callback may free
+ * the object (last active vma). To prevent the explosion
+ * we defer the actual object free to a worker that can
+ * only proceed once it acquires the struct_mutex (which
+ * we currently hold, therefore it cannot free this object
+ * before we are finished).
+ */
+ __i915_vma_pin(vma);
+
+ for_each_active(active, idx) {
+ ret = i915_gem_active_retire(&vma->last_read[idx],
+ &vma->vm->i915->drm.struct_mutex);
+ if (ret)
+ break;
+ }
+
+ __i915_vma_unpin(vma);
+ if (ret)
+ return ret;
+
+ GEM_BUG_ON(i915_vma_is_active(vma));
+ }
+
+ if (i915_vma_is_pinned(vma))
+ return -EBUSY;
+
+ if (!drm_mm_node_allocated(&vma->node))
+ goto destroy;
+
+ GEM_BUG_ON(obj->bind_count == 0);
+ GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj));
+
+ if (i915_vma_is_map_and_fenceable(vma)) {
+ /* release the fence reg _after_ flushing */
+ ret = i915_vma_put_fence(vma);
+ if (ret)
+ return ret;
+
+ /* Force a pagefault for domain tracking on next user access */
+ i915_gem_release_mmap(obj);
+
+ __i915_vma_iounmap(vma);
+ vma->flags &= ~I915_VMA_CAN_FENCE;
+ }
+
+ if (likely(!vma->vm->closed)) {
+ trace_i915_vma_unbind(vma);
+ vma->vm->unbind_vma(vma);
+ }
+ vma->flags &= ~(I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND);
+
+ if (vma->pages != obj->mm.pages) {
+ GEM_BUG_ON(!vma->pages);
+ sg_free_table(vma->pages);
+ kfree(vma->pages);
+ }
+ vma->pages = NULL;
+
+ i915_vma_remove(vma);
+
+destroy:
+ if (unlikely(i915_vma_is_closed(vma)))
+ i915_vma_destroy(vma);
+
+ return 0;
+}
+