drm/ttm: revert "add optional LRU removal callback v2"

Without the custom LRU management the callback is not used any more.

agd: fix trivial warning
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-and-Tested-by: Roger.He <Hongbo.He@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/ttm/ttm_bo.c

@@ -186,12 +186,8 @@ EXPORT_SYMBOL(ttm_bo_add_to_lru);
 
 int ttm_bo_del_from_lru(struct ttm_buffer_object *bo)
 {
-	struct ttm_bo_device *bdev = bo->bdev;
 	int put_count = 0;
 
-	if (bdev->driver->lru_removal)
-		bdev->driver->lru_removal(bo);
-
 	if (!list_empty(&bo->swap)) {
 		list_del_init(&bo->swap);
 		++put_count;
@@ -201,6 +197,11 @@ int ttm_bo_del_from_lru(struct ttm_buffer_object *bo)
 		++put_count;
 	}
 
+	/*
+	 * TODO: Add a driver hook to delete from
+	 * driver-specific LRU's here.
+	 */
+
 	return put_count;
 }
 
@@ -229,14 +230,10 @@ EXPORT_SYMBOL(ttm_bo_del_sub_from_lru);
 
 void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo)
 {
-	struct ttm_bo_device *bdev = bo->bdev;
 	int put_count = 0;
 
 	lockdep_assert_held(&bo->resv->lock.base);
 
-	if (bdev->driver->lru_removal)
-		bdev->driver->lru_removal(bo);
-
 	put_count = ttm_bo_del_from_lru(bo);
 	ttm_bo_list_ref_sub(bo, put_count, true);
 	ttm_bo_add_to_lru(bo);

include/drm/ttm/ttm_bo_driver.h

@@ -462,12 +462,6 @@ struct ttm_bo_driver {
 			      struct ttm_mem_reg *mem);
 	void (*io_mem_free)(struct ttm_bo_device *bdev,
 			    struct ttm_mem_reg *mem);
-
-	/**
-	 * Optional driver callback for when BO is removed from the LRU.
-	 * Called with LRU lock held immediately before the removal.
-	 */
-	void (*lru_removal)(struct ttm_buffer_object *bo);
 };
 
 /**