From 997e91885e700a7b175c98f0e64670ed4fd57bc0 Mon Sep 17 00:00:00 2001
From: Eric Anholt <eric@anholt.net>
Date: Wed, 19 Nov 2014 12:06:38 -0800
Subject: [PATCH] drm: Put an optional field in the driver struct for GEM obj
 struct size.

This allows a driver to derive from the CMA object without copying all
of the code.

Signed-off-by: Eric Anholt <eric@anholt.net>
---
 drivers/gpu/drm/drm_gem_cma_helper.c | 5 ++++-
 include/drm/drmP.h                   | 1 +
 2 files changed, 5 insertions(+), 1 deletion(-)

--- a/drivers/gpu/drm/drm_gem_cma_helper.c
+++ b/drivers/gpu/drm/drm_gem_cma_helper.c
@@ -58,8 +58,11 @@ __drm_gem_cma_create(struct drm_device *
 	struct drm_gem_cma_object *cma_obj;
 	struct drm_gem_object *gem_obj;
 	int ret;
+	size_t obj_size = (drm->driver->gem_obj_size ?
+			   drm->driver->gem_obj_size :
+			   sizeof(*cma_obj));
 
-	cma_obj = kzalloc(sizeof(*cma_obj), GFP_KERNEL);
+	cma_obj = kzalloc(obj_size, GFP_KERNEL);
 	if (!cma_obj)
 		return ERR_PTR(-ENOMEM);
 
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -653,6 +653,7 @@ struct drm_driver {
 
 	u32 driver_features;
 	int dev_priv_size;
+	size_t gem_obj_size;
 	const struct drm_ioctl_desc *ioctls;
 	int num_ioctls;
 	const struct file_operations *fops;
