[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.koe...@amd.com>
Signed-off-by: Arunpravin Paneer Selvam <arunpravin.paneersel...@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