drm/i915: Add kerneldoc to describe i915_gem_object.vma_list

Add kerneldoc for the vma_list stored on the i915_gem_object, in
particular, documenting the expected ordering of elements -- i.e. that
we do expect GGTT VMA first followed by the ppGTT VMA.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170525204818.12044-1-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
This commit is contained in:
Chris Wilson 2017-05-25 21:48:18 +01:00
parent 630d30a4ee
commit b5a824250e
1 changed files with 16 additions and 1 deletions

View File

@ -68,8 +68,23 @@ struct drm_i915_gem_object {
const struct drm_i915_gem_object_ops *ops;
/** List of VMAs backed by this object */
/**
* @vma_list: List of VMAs backed by this object
*
* The VMA on this list are ordered by type, all GGTT vma are placed
* at the head and all ppGTT vma are placed at the tail. The different
* types of GGTT vma are unordered between themselves, use the
* @vma_tree (which has a defined order between all VMA) to find an
* exact match.
*/
struct list_head vma_list;
/**
* @vma_tree: Ordered tree of VMAs backed by this object
*
* All VMA created for this object are placed in the @vma_tree for
* fast retrieval via a binary search in i915_vma_instance().
* They are also added to @vma_list for easy iteration.
*/
struct rb_root vma_tree;
/** Stolen memory for this object, instead of being backed by shmem. */