diff mbox

[v2,2/5] drm/i915: Do not make assumptions on GGTT VMA sizes

Message ID 1430392771.1189.7.camel@jlahtine-mobl1 (mailing list archive)
State New, archived
Headers show

Commit Message

Joonas Lahtinen April 30, 2015, 11:19 a.m. UTC
GGTT VMA sizes might be smaller than the whole object size due to
different GGTT views.

v2:
- Separate GGTT view constraint calculations from normal view
  constraint calculations (Chris Wilson)
v3:
- Do not bother with debug wording. (Tvrtko Ursulin)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
---
 drivers/gpu/drm/i915/i915_gem.c     | 103 +++++++++++++++++++++++-------------
 drivers/gpu/drm/i915/i915_gem_gtt.c |  23 ++++++++
 drivers/gpu/drm/i915/i915_gem_gtt.h |   4 ++
 3 files changed, 92 insertions(+), 38 deletions(-)

Comments

Tvrtko Ursulin April 30, 2015, 12:03 p.m. UTC | #1
On 04/30/2015 12:19 PM, Joonas Lahtinen wrote:
>
> GGTT VMA sizes might be smaller than the whole object size due to
> different GGTT views.
>
> v2:
> - Separate GGTT view constraint calculations from normal view
>    constraint calculations (Chris Wilson)
> v3:
> - Do not bother with debug wording. (Tvrtko Ursulin)
>
> Cc: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
> Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
> ---
>   drivers/gpu/drm/i915/i915_gem.c     | 103 +++++++++++++++++++++++-------------
>   drivers/gpu/drm/i915/i915_gem_gtt.c |  23 ++++++++
>   drivers/gpu/drm/i915/i915_gem_gtt.h |   4 ++
>   3 files changed, 92 insertions(+), 38 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index e8f6f4c..9717c9d 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -3497,7 +3497,8 @@ static bool i915_gem_valid_gtt_space(struct i915_vma *vma,
>   }
>
>   /**
> - * Finds free space in the GTT aperture and binds the object there.
> + * Finds free space in the GTT aperture and binds the object or a view of it
> + * there.
>    */
>   static struct i915_vma *
>   i915_gem_object_bind_to_vm(struct drm_i915_gem_object *obj,
> @@ -3516,36 +3517,60 @@ i915_gem_object_bind_to_vm(struct drm_i915_gem_object *obj,
>   	struct i915_vma *vma;
>   	int ret;
>
> -	if(WARN_ON(i915_is_ggtt(vm) != !!ggtt_view))
> -		return ERR_PTR(-EINVAL);
> +	if (i915_is_ggtt(vm)) {
> +		u32 view_size;
> +
> +		if (WARN_ON(!ggtt_view))
> +			return ERR_PTR(-EINVAL);
>
> -	fence_size = i915_gem_get_gtt_size(dev,
> -					   obj->base.size,
> -					   obj->tiling_mode);
> -	fence_alignment = i915_gem_get_gtt_alignment(dev,
> -						     obj->base.size,
> -						     obj->tiling_mode, true);
> -	unfenced_alignment =
> -		i915_gem_get_gtt_alignment(dev,
> -					   obj->base.size,
> -					   obj->tiling_mode, false);
> +		view_size = i915_ggtt_view_size(obj, ggtt_view);
> +
> +		fence_size = i915_gem_get_gtt_size(dev,
> +						   view_size,
> +						   obj->tiling_mode);
> +		fence_alignment = i915_gem_get_gtt_alignment(dev,
> +							     view_size,
> +							     obj->tiling_mode,
> +							     true);
> +		unfenced_alignment = i915_gem_get_gtt_alignment(dev,
> +								view_size,
> +								obj->tiling_mode,
> +								false);
> +		size = flags & PIN_MAPPABLE ? fence_size : view_size;
> +	} else {
> +		fence_size = i915_gem_get_gtt_size(dev,
> +						   obj->base.size,
> +						   obj->tiling_mode);
> +		fence_alignment = i915_gem_get_gtt_alignment(dev,
> +							     obj->base.size,
> +							     obj->tiling_mode,
> +							     true);
> +		unfenced_alignment =
> +			i915_gem_get_gtt_alignment(dev,
> +						   obj->base.size,
> +						   obj->tiling_mode,
> +						   false);
> +		size = flags & PIN_MAPPABLE ? fence_size : obj->base.size;
> +	}

I do not like this almost identical branches - so I defer to Chris to 
okay that this is what he wanted.

>   	if (alignment == 0)
>   		alignment = flags & PIN_MAPPABLE ? fence_alignment :
>   						unfenced_alignment;
>   	if (flags & PIN_MAPPABLE && alignment & (fence_alignment - 1)) {
> -		DRM_DEBUG("Invalid object alignment requested %u\n", alignment);
> +		DRM_DEBUG("Invalid object (view type=%u) alignment requested %u\n",
> +			  ggtt_view ? ggtt_view->type : 0,
> +			  alignment);
>   		return ERR_PTR(-EINVAL);
>   	}
>
> -	size = flags & PIN_MAPPABLE ? fence_size : obj->base.size;
> -
> -	/* If the object is bigger than the entire aperture, reject it early
> -	 * before evicting everything in a vain attempt to find space.
> +	/* 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 (obj->base.size > end) {
> -		DRM_DEBUG("Attempting to bind an object larger than the aperture: object=%zd > %s aperture=%lu\n",
> -			  obj->base.size,
> +	if (size > end) {
> +		DRM_DEBUG("Attempting to bind an object (view type=%u) larger than the aperture: size=%u > %s aperture=%lu\n",
> +			  ggtt_view ? ggtt_view->type : 0,
> +			  size,
>   			  flags & PIN_MAPPABLE ? "mappable" : "total",
>   			  end);
>   		return ERR_PTR(-E2BIG);
> @@ -4207,28 +4232,30 @@ i915_gem_object_do_pin(struct drm_i915_gem_object *obj,
>   			return ret;
>   	}
>
> -	if ((bound ^ vma->bound) & GLOBAL_BIND) {
> -		bool mappable, fenceable;
> -		u32 fence_size, fence_alignment;
> +	if (!ggtt_view || ggtt_view->type == I915_GGTT_VIEW_NORMAL) {
> +		if ((bound ^ vma->bound) & GLOBAL_BIND) {

I still don't get this. !ggtt_view means GLOBAL_BIND cannot be set, what 
am I missing? It wouldn't work if the condition was just the type check?

> +			bool mappable, fenceable;
> +			u32 fence_size, fence_alignment;
>
> -		fence_size = i915_gem_get_gtt_size(obj->base.dev,
> -						   obj->base.size,
> -						   obj->tiling_mode);
> -		fence_alignment = i915_gem_get_gtt_alignment(obj->base.dev,
> -							     obj->base.size,
> -							     obj->tiling_mode,
> -							     true);
> +			fence_size = i915_gem_get_gtt_size(obj->base.dev,
> +							   obj->base.size,
> +							   obj->tiling_mode);
> +			fence_alignment = i915_gem_get_gtt_alignment(obj->base.dev,
> +								     obj->base.size,
> +								     obj->tiling_mode,
> +								     true);
>
> -		fenceable = (vma->node.size == fence_size &&
> -			     (vma->node.start & (fence_alignment - 1)) == 0);
> +			fenceable = (vma->node.size == fence_size &&
> +				     (vma->node.start & (fence_alignment - 1)) == 0);
>
> -		mappable = (vma->node.start + fence_size <=
> -			    dev_priv->gtt.mappable_end);
> +			mappable = (vma->node.start + fence_size <=
> +				    dev_priv->gtt.mappable_end);
>
> -		obj->map_and_fenceable = mappable && fenceable;
> -	}
> +			obj->map_and_fenceable = mappable && fenceable;
> +		}
>
> -	WARN_ON(flags & PIN_MAPPABLE && !obj->map_and_fenceable);
> +		WARN_ON(flags & PIN_MAPPABLE && !obj->map_and_fenceable);
> +	}
>
>   	vma->pin_count++;
>   	return 0;
> diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
> index fc562c6..640584f 100644
> --- a/drivers/gpu/drm/i915/i915_gem_gtt.c
> +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
> @@ -2847,3 +2847,26 @@ int i915_vma_bind(struct i915_vma *vma, enum i915_cache_level cache_level,
>
>   	return 0;
>   }
> +
> +/**
> + * i915_ggtt_view_size - Get the size of a GGTT view.
> + * @obj: Object the view is of.
> + * @view: The view in question.
> + *
> + * @return The size of the GGTT view in bytes.
> + */
> +size_t
> +i915_ggtt_view_size(struct drm_i915_gem_object *obj,
> +		    const struct i915_ggtt_view *view)
> +{
> +	BUG_ON(!view);

It is a marginal point, but I wonder is size zero could be considered as 
a failure value and acted upon from the caller more gracefuly.

And in general I wonder if something like I915_BUG_ON which would 
re-route fops to fail-all and grab struct_mutex, or something, would 
maybe be an option.

Regards,

Tvrtko
Joonas Lahtinen May 6, 2015, 11:43 a.m. UTC | #2
On to, 2015-04-30 at 13:03 +0100, Tvrtko Ursulin wrote:
> On 04/30/2015 12:19 PM, Joonas Lahtinen wrote:
> >
> > GGTT VMA sizes might be smaller than the whole object size due to
> > different GGTT views.
> >
> > v2:
> > - Separate GGTT view constraint calculations from normal view
> >    constraint calculations (Chris Wilson)
> > v3:
> > - Do not bother with debug wording. (Tvrtko Ursulin)
> >
> > Cc: Chris Wilson <chris@chris-wilson.co.uk>
> > Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
> > Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
> > ---
> >   drivers/gpu/drm/i915/i915_gem.c     | 103 +++++++++++++++++++++++-------------
> >   drivers/gpu/drm/i915/i915_gem_gtt.c |  23 ++++++++
> >   drivers/gpu/drm/i915/i915_gem_gtt.h |   4 ++
> >   3 files changed, 92 insertions(+), 38 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> > index e8f6f4c..9717c9d 100644
> > --- a/drivers/gpu/drm/i915/i915_gem.c
> > +++ b/drivers/gpu/drm/i915/i915_gem.c
> > @@ -3497,7 +3497,8 @@ static bool i915_gem_valid_gtt_space(struct i915_vma *vma,
> >   }
> >
> >   /**
> > - * Finds free space in the GTT aperture and binds the object there.
> > + * Finds free space in the GTT aperture and binds the object or a view of it
> > + * there.
> >    */
> >   static struct i915_vma *
> >   i915_gem_object_bind_to_vm(struct drm_i915_gem_object *obj,
> > @@ -3516,36 +3517,60 @@ i915_gem_object_bind_to_vm(struct drm_i915_gem_object *obj,
> >   	struct i915_vma *vma;
> >   	int ret;
> >
> > -	if(WARN_ON(i915_is_ggtt(vm) != !!ggtt_view))
> > -		return ERR_PTR(-EINVAL);
> > +	if (i915_is_ggtt(vm)) {
> > +		u32 view_size;
> > +
> > +		if (WARN_ON(!ggtt_view))
> > +			return ERR_PTR(-EINVAL);
> >
> > -	fence_size = i915_gem_get_gtt_size(dev,
> > -					   obj->base.size,
> > -					   obj->tiling_mode);
> > -	fence_alignment = i915_gem_get_gtt_alignment(dev,
> > -						     obj->base.size,
> > -						     obj->tiling_mode, true);
> > -	unfenced_alignment =
> > -		i915_gem_get_gtt_alignment(dev,
> > -					   obj->base.size,
> > -					   obj->tiling_mode, false);
> > +		view_size = i915_ggtt_view_size(obj, ggtt_view);
> > +
> > +		fence_size = i915_gem_get_gtt_size(dev,
> > +						   view_size,
> > +						   obj->tiling_mode);
> > +		fence_alignment = i915_gem_get_gtt_alignment(dev,
> > +							     view_size,
> > +							     obj->tiling_mode,
> > +							     true);
> > +		unfenced_alignment = i915_gem_get_gtt_alignment(dev,
> > +								view_size,
> > +								obj->tiling_mode,
> > +								false);
> > +		size = flags & PIN_MAPPABLE ? fence_size : view_size;
> > +	} else {
> > +		fence_size = i915_gem_get_gtt_size(dev,
> > +						   obj->base.size,
> > +						   obj->tiling_mode);
> > +		fence_alignment = i915_gem_get_gtt_alignment(dev,
> > +							     obj->base.size,
> > +							     obj->tiling_mode,
> > +							     true);
> > +		unfenced_alignment =
> > +			i915_gem_get_gtt_alignment(dev,
> > +						   obj->base.size,
> > +						   obj->tiling_mode,
> > +						   false);
> > +		size = flags & PIN_MAPPABLE ? fence_size : obj->base.size;
> > +	}
> 
> I do not like this almost identical branches - so I defer to Chris to 
> okay that this is what he wanted.
> 

Confirmed in IRC that the above is according to what Chris meant.

> >   	if (alignment == 0)
> >   		alignment = flags & PIN_MAPPABLE ? fence_alignment :
> >   						unfenced_alignment;
> >   	if (flags & PIN_MAPPABLE && alignment & (fence_alignment - 1)) {
> > -		DRM_DEBUG("Invalid object alignment requested %u\n", alignment);
> > +		DRM_DEBUG("Invalid object (view type=%u) alignment requested %u\n",
> > +			  ggtt_view ? ggtt_view->type : 0,
> > +			  alignment);
> >   		return ERR_PTR(-EINVAL);
> >   	}
> >
> > -	size = flags & PIN_MAPPABLE ? fence_size : obj->base.size;
> > -
> > -	/* If the object is bigger than the entire aperture, reject it early
> > -	 * before evicting everything in a vain attempt to find space.
> > +	/* 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 (obj->base.size > end) {
> > -		DRM_DEBUG("Attempting to bind an object larger than the aperture: object=%zd > %s aperture=%lu\n",
> > -			  obj->base.size,
> > +	if (size > end) {
> > +		DRM_DEBUG("Attempting to bind an object (view type=%u) larger than the aperture: size=%u > %s aperture=%lu\n",
> > +			  ggtt_view ? ggtt_view->type : 0,
> > +			  size,
> >   			  flags & PIN_MAPPABLE ? "mappable" : "total",
> >   			  end);
> >   		return ERR_PTR(-E2BIG);
> > @@ -4207,28 +4232,30 @@ i915_gem_object_do_pin(struct drm_i915_gem_object *obj,
> >   			return ret;
> >   	}
> >
> > -	if ((bound ^ vma->bound) & GLOBAL_BIND) {
> > -		bool mappable, fenceable;
> > -		u32 fence_size, fence_alignment;
> > +	if (!ggtt_view || ggtt_view->type == I915_GGTT_VIEW_NORMAL) {
> > +		if ((bound ^ vma->bound) & GLOBAL_BIND) {
> 
> I still don't get this. !ggtt_view means GLOBAL_BIND cannot be set, what 
> am I missing? It wouldn't work if the condition was just the type check?
> 

Clarified this.

> > +			bool mappable, fenceable;
> > +			u32 fence_size, fence_alignment;
> >
> > -		fence_size = i915_gem_get_gtt_size(obj->base.dev,
> > -						   obj->base.size,
> > -						   obj->tiling_mode);
> > -		fence_alignment = i915_gem_get_gtt_alignment(obj->base.dev,
> > -							     obj->base.size,
> > -							     obj->tiling_mode,
> > -							     true);
> > +			fence_size = i915_gem_get_gtt_size(obj->base.dev,
> > +							   obj->base.size,
> > +							   obj->tiling_mode);
> > +			fence_alignment = i915_gem_get_gtt_alignment(obj->base.dev,
> > +								     obj->base.size,
> > +								     obj->tiling_mode,
> > +								     true);
> >
> > -		fenceable = (vma->node.size == fence_size &&
> > -			     (vma->node.start & (fence_alignment - 1)) == 0);
> > +			fenceable = (vma->node.size == fence_size &&
> > +				     (vma->node.start & (fence_alignment - 1)) == 0);
> >
> > -		mappable = (vma->node.start + fence_size <=
> > -			    dev_priv->gtt.mappable_end);
> > +			mappable = (vma->node.start + fence_size <=
> > +				    dev_priv->gtt.mappable_end);
> >
> > -		obj->map_and_fenceable = mappable && fenceable;
> > -	}
> > +			obj->map_and_fenceable = mappable && fenceable;
> > +		}
> >
> > -	WARN_ON(flags & PIN_MAPPABLE && !obj->map_and_fenceable);
> > +		WARN_ON(flags & PIN_MAPPABLE && !obj->map_and_fenceable);
> > +	}
> >
> >   	vma->pin_count++;
> >   	return 0;
> > diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
> > index fc562c6..640584f 100644
> > --- a/drivers/gpu/drm/i915/i915_gem_gtt.c
> > +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
> > @@ -2847,3 +2847,26 @@ int i915_vma_bind(struct i915_vma *vma, enum i915_cache_level cache_level,
> >
> >   	return 0;
> >   }
> > +
> > +/**
> > + * i915_ggtt_view_size - Get the size of a GGTT view.
> > + * @obj: Object the view is of.
> > + * @view: The view in question.
> > + *
> > + * @return The size of the GGTT view in bytes.
> > + */
> > +size_t
> > +i915_ggtt_view_size(struct drm_i915_gem_object *obj,
> > +		    const struct i915_ggtt_view *view)
> > +{
> > +	BUG_ON(!view);
> 
> It is a marginal point, but I wonder is size zero could be considered as 
> a failure value and acted upon from the caller more gracefuly.
> 
> And in general I wonder if something like I915_BUG_ON which would 
> re-route fops to fail-all and grab struct_mutex, or something, would 
> maybe be an option.
> 

I wouldn't like to overcomplicate the error handling for for imaginary
or promille use cases, so I think it is a good rule of thumb that bug on
if the kernel would OOPS anyway (which holds here).

Regards, Joonas

> Regards,
> 
> Tvrtko
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index e8f6f4c..9717c9d 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -3497,7 +3497,8 @@  static bool i915_gem_valid_gtt_space(struct i915_vma *vma,
 }
 
 /**
- * Finds free space in the GTT aperture and binds the object there.
+ * Finds free space in the GTT aperture and binds the object or a view of it
+ * there.
  */
 static struct i915_vma *
 i915_gem_object_bind_to_vm(struct drm_i915_gem_object *obj,
@@ -3516,36 +3517,60 @@  i915_gem_object_bind_to_vm(struct drm_i915_gem_object *obj,
 	struct i915_vma *vma;
 	int ret;
 
-	if(WARN_ON(i915_is_ggtt(vm) != !!ggtt_view))
-		return ERR_PTR(-EINVAL);
+	if (i915_is_ggtt(vm)) {
+		u32 view_size;
+
+		if (WARN_ON(!ggtt_view))
+			return ERR_PTR(-EINVAL);
 
-	fence_size = i915_gem_get_gtt_size(dev,
-					   obj->base.size,
-					   obj->tiling_mode);
-	fence_alignment = i915_gem_get_gtt_alignment(dev,
-						     obj->base.size,
-						     obj->tiling_mode, true);
-	unfenced_alignment =
-		i915_gem_get_gtt_alignment(dev,
-					   obj->base.size,
-					   obj->tiling_mode, false);
+		view_size = i915_ggtt_view_size(obj, ggtt_view);
+
+		fence_size = i915_gem_get_gtt_size(dev,
+						   view_size,
+						   obj->tiling_mode);
+		fence_alignment = i915_gem_get_gtt_alignment(dev,
+							     view_size,
+							     obj->tiling_mode,
+							     true);
+		unfenced_alignment = i915_gem_get_gtt_alignment(dev,
+								view_size,
+								obj->tiling_mode,
+								false);
+		size = flags & PIN_MAPPABLE ? fence_size : view_size;
+	} else {
+		fence_size = i915_gem_get_gtt_size(dev,
+						   obj->base.size,
+						   obj->tiling_mode);
+		fence_alignment = i915_gem_get_gtt_alignment(dev,
+							     obj->base.size,
+							     obj->tiling_mode,
+							     true);
+		unfenced_alignment =
+			i915_gem_get_gtt_alignment(dev,
+						   obj->base.size,
+						   obj->tiling_mode,
+						   false);
+		size = flags & PIN_MAPPABLE ? fence_size : obj->base.size;
+	}
 
 	if (alignment == 0)
 		alignment = flags & PIN_MAPPABLE ? fence_alignment :
 						unfenced_alignment;
 	if (flags & PIN_MAPPABLE && alignment & (fence_alignment - 1)) {
-		DRM_DEBUG("Invalid object alignment requested %u\n", alignment);
+		DRM_DEBUG("Invalid object (view type=%u) alignment requested %u\n",
+			  ggtt_view ? ggtt_view->type : 0,
+			  alignment);
 		return ERR_PTR(-EINVAL);
 	}
 
-	size = flags & PIN_MAPPABLE ? fence_size : obj->base.size;
-
-	/* If the object is bigger than the entire aperture, reject it early
-	 * before evicting everything in a vain attempt to find space.
+	/* 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 (obj->base.size > end) {
-		DRM_DEBUG("Attempting to bind an object larger than the aperture: object=%zd > %s aperture=%lu\n",
-			  obj->base.size,
+	if (size > end) {
+		DRM_DEBUG("Attempting to bind an object (view type=%u) larger than the aperture: size=%u > %s aperture=%lu\n",
+			  ggtt_view ? ggtt_view->type : 0,
+			  size,
 			  flags & PIN_MAPPABLE ? "mappable" : "total",
 			  end);
 		return ERR_PTR(-E2BIG);
@@ -4207,28 +4232,30 @@  i915_gem_object_do_pin(struct drm_i915_gem_object *obj,
 			return ret;
 	}
 
-	if ((bound ^ vma->bound) & GLOBAL_BIND) {
-		bool mappable, fenceable;
-		u32 fence_size, fence_alignment;
+	if (!ggtt_view || ggtt_view->type == I915_GGTT_VIEW_NORMAL) {
+		if ((bound ^ vma->bound) & GLOBAL_BIND) {
+			bool mappable, fenceable;
+			u32 fence_size, fence_alignment;
 
-		fence_size = i915_gem_get_gtt_size(obj->base.dev,
-						   obj->base.size,
-						   obj->tiling_mode);
-		fence_alignment = i915_gem_get_gtt_alignment(obj->base.dev,
-							     obj->base.size,
-							     obj->tiling_mode,
-							     true);
+			fence_size = i915_gem_get_gtt_size(obj->base.dev,
+							   obj->base.size,
+							   obj->tiling_mode);
+			fence_alignment = i915_gem_get_gtt_alignment(obj->base.dev,
+								     obj->base.size,
+								     obj->tiling_mode,
+								     true);
 
-		fenceable = (vma->node.size == fence_size &&
-			     (vma->node.start & (fence_alignment - 1)) == 0);
+			fenceable = (vma->node.size == fence_size &&
+				     (vma->node.start & (fence_alignment - 1)) == 0);
 
-		mappable = (vma->node.start + fence_size <=
-			    dev_priv->gtt.mappable_end);
+			mappable = (vma->node.start + fence_size <=
+				    dev_priv->gtt.mappable_end);
 
-		obj->map_and_fenceable = mappable && fenceable;
-	}
+			obj->map_and_fenceable = mappable && fenceable;
+		}
 
-	WARN_ON(flags & PIN_MAPPABLE && !obj->map_and_fenceable);
+		WARN_ON(flags & PIN_MAPPABLE && !obj->map_and_fenceable);
+	}
 
 	vma->pin_count++;
 	return 0;
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index fc562c6..640584f 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -2847,3 +2847,26 @@  int i915_vma_bind(struct i915_vma *vma, enum i915_cache_level cache_level,
 
 	return 0;
 }
+
+/**
+ * i915_ggtt_view_size - Get the size of a GGTT view.
+ * @obj: Object the view is of.
+ * @view: The view in question.
+ *
+ * @return The size of the GGTT view in bytes.
+ */
+size_t
+i915_ggtt_view_size(struct drm_i915_gem_object *obj,
+		    const struct i915_ggtt_view *view)
+{
+	BUG_ON(!view);
+
+	if (view->type == I915_GGTT_VIEW_NORMAL ||
+	    view->type == I915_GGTT_VIEW_ROTATED) {
+		return obj->base.size;
+	} else {
+		WARN_ONCE(1, "GGTT view %u not implemented!\n", view->type);
+		return obj->base.size;
+	}
+}
+
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h
index 4e6cac5..34b7cca 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.h
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
@@ -498,4 +498,8 @@  i915_ggtt_view_equal(const struct i915_ggtt_view *a,
 	return a->type == b->type;
 }
 
+size_t
+i915_ggtt_view_size(struct drm_i915_gem_object *obj,
+		    const struct i915_ggtt_view *view);
+
 #endif