[PATCH 2/4] drm/i915: Add intersect callback function

[Arunpravin Paneer Selvam]

Add a new intersect callback function fetching
start offset from backend drm buddy allocator.

Signed-off-by: Christian König <christian.koenig at amd.com>
Signed-off-by: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam at amd.com>
---
 drivers/gpu/drm/i915/i915_ttm_buddy_manager.c | 23 +++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c
index a5109548abc0..30bb8ade67a9 100644
--- a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c
+++ b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c
@@ -178,6 +178,28 @@ static void i915_ttm_buddy_man_free(struct ttm_resource_manager *man,
 	kfree(bman_res);
 }
 
+static bool i915_ttm_buddy_man_intersect(struct ttm_resource_manager *man,
+					 struct ttm_resource *res,
+					 const struct ttm_place *place,
+					 size_t size)
+{
+	struct i915_ttm_buddy_resource *bman_res = to_ttm_buddy_resource(res);
+	struct list_head *list = &bman_res->blocks;
+	struct drm_buddy_block *block;
+	u32 num_pages = PFN_UP(size);
+	u32 start;
+
+	/* Check each drm buddy block individually */
+	list_for_each_entry(block, list, link) {
+		start = drm_buddy_block_offset(block) >> PAGE_SHIFT;
+		if (start < place->fpfn ||
+		    (place->lpfn && (start + num_pages) > place->lpfn))
+			return false;
+	}
+
+	return true;
+}
+
 static void i915_ttm_buddy_man_debug(struct ttm_resource_manager *man,
 				     struct drm_printer *printer)
 {
@@ -205,6 +227,7 @@ static void i915_ttm_buddy_man_debug(struct ttm_resource_manager *man,
 static const struct ttm_resource_manager_func i915_ttm_buddy_manager_func = {
 	.alloc = i915_ttm_buddy_man_alloc,
 	.free = i915_ttm_buddy_man_free,
+	.intersect = i915_ttm_buddy_man_intersect,
 	.debug = i915_ttm_buddy_man_debug,
 };
 
-- 
2.25.1