drm/i915: Create VMAs

Formerly: "drm/i915: Create VMAs (part 1)"

In a previous patch, the notion of a VM was introduced. A VMA describes
an area of part of the VM address space. A VMA is similar to the concept
in the linux mm. However, instead of representing regular memory, a VMA
is backed by a GEM BO. There may be many VMAs for a given object, one
for each VM the object is to be used in. This may occur through flink,
dma-buf, or a number of other transient states.

Currently the code depends on only 1 VMA per object, for the global GTT
(and aliasing PPGTT). The following patches will address this and make
the rest of the infrastructure more suited

v2: s/i915_obj/i915_gem_obj (Chris)

v3: Only move an object to the now global unbound list if there are no
more VMAs for the object which are bound into a VM (ie. the list is
empty).

v4: killed obj->gtt_space
some reworks due to rebase

v5: Free vma on error path (Imre)

v6: Another missed vma free in i915_gem_object_bind_to_gtt error path
(Imre)
Fixed vma freeing in stolen preallocation (Imre)

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Imre Deak <imre.deak@intel.com>
[danvet: Squash in fixup from Ben to not deref a non-existing vma in
set_cache_level, reported by Chris.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 11 insertions, 4 deletions

diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
index cb527e7930ad..fc894f7d32e1 100644
--- a/drivers/gpu/drm/i915/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
@@ -351,6 +351,7 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
 	struct i915_address_space *vm = &dev_priv->gtt.base;
 	struct drm_i915_gem_object *obj;
 	struct drm_mm_node *stolen;
+	struct i915_vma *vma;
 	int ret;
 
 	if (dev_priv->mm.stolen_base == 0)
@@ -390,18 +391,24 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
 	if (gtt_offset == I915_GTT_OFFSET_NONE)
 		return obj;
 
+	vma = i915_gem_vma_create(obj, &dev_priv->gtt.base);
+	if (!vma) {
+		ret = -ENOMEM;
+		goto err_out;
+	}
+
 	/* To simplify the initialisation sequence between KMS and GTT,
 	 * we allow construction of the stolen object prior to
 	 * setting up the GTT space. The actual reservation will occur
 	 * later.
 	 */
-	obj->gtt_space.start = gtt_offset;
-	obj->gtt_space.size = size;
+	vma->node.start = gtt_offset;
+	vma->node.size = size;
 	if (drm_mm_initialized(&dev_priv->gtt.base.mm)) {
-		ret = drm_mm_reserve_node(&dev_priv->gtt.base.mm,
-					  &obj->gtt_space);
+		ret = drm_mm_reserve_node(&dev_priv->gtt.base.mm, &vma->node);
 		if (ret) {
 			DRM_DEBUG_KMS("failed to allocate stolen GTT space\n");
+			i915_gem_vma_destroy(vma);
 			goto err_out;
 		}
 	}