drm/i915: Tidy i915_gem_valid_gtt_space()

We can replace a couple of tests with an assertion that the passed in
node is already allocated (as matches the existing call convention) and
by a small bit of refactoring we can bring the line lengths to under
80cols.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161205142941.21965-3-chris@chris-wilson.co.uk

diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
index bc077e51b3e70048f11c48f942fb43844e33e453..37c3eebe8316a7c249e14396f90709a099222ebc 100644 (file)
--- a/drivers/gpu/drm/i915/i915_vma.c
+++ b/drivers/gpu/drm/i915/i915_vma.c
@@ -297,10 +297,14 @@ void __i915_vma_set_map_and_fenceable(struct i915_vma *vma)
                vma->flags &= ~I915_VMA_CAN_FENCE;
 }
 
-bool i915_gem_valid_gtt_space(struct i915_vma *vma,
-                             unsigned long cache_level)
+static bool color_differs(struct drm_mm_node *node, unsigned long color)
 {
-       struct drm_mm_node *gtt_space = &vma->node;
+       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;
 
        /*
@@ -313,18 +317,16 @@ bool i915_gem_valid_gtt_space(struct i915_vma *vma,
        if (vma->vm->mm.color_adjust == NULL)
                return true;
 
-       if (!drm_mm_node_allocated(gtt_space))
-               return true;
-
-       if (list_empty(&gtt_space->node_list))
-               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_entry(gtt_space->node_list.prev, struct drm_mm_node, node_list);
-       if (other->allocated && !other->hole_follows && other->color != cache_level)
+       other = list_prev_entry(node, node_list);
+       if (color_differs(other, cache_level) && !other->hole_follows)
                return false;
 
-       other = list_entry(gtt_space->node_list.next, struct drm_mm_node, node_list);
-       if (other->allocated && !gtt_space->hole_follows && other->color != cache_level)
+       other = list_next_entry(node, node_list);
+       if (color_differs(other, cache_level) && !node->hole_follows)
                return false;
 
        return true;