New subject: [Intel-gfx] [PATCH 01/11] drm: Export drm_dev_init() for subclassing

27 May 2016

In order to allow drivers to pack their privates and drm_device into one
struct (e.g. for subclassing), export the initialisation routines for
struct drm_device.
Signed-off-by: Chris Wilson chris@chris-wilson.co.uk
Cc: Daniel Vetter daniel.vetter@ffwll.ch
Cc: dri-devel@lists.freedesktop.org
---
 drivers/gpu/drm/drm_drv.c | 63 ++++++++++++++++++++++++++++++++++++-----------
 include/drm/drmP.h        |  3 +++
 2 files changed, 52 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index bff89226a344..ceb85e611a07 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -549,11 +549,12 @@ static void drm_fs_inode_free(struct inode *inode)
 }
/**
- * drm_dev_alloc - Allocate new DRM device
- * @driver: DRM driver to allocate device for
+ * drm_dev_init - Initialise new DRM device
+ * @dev: DRM device
+ * @driver: DRM driver
  * @parent: Parent device object
  *
- * Allocate and initialize a new DRM device. No device registration is done.
+ * Initialize a new DRM device. No device registration is done.
  * Call drm_dev_register() to advertice the device to user space and register it
  * with other core subsystems. This should be done last in the device
  * initialization sequence to make sure userspace can't access an inconsistent
@@ -565,18 +566,14 @@ static void drm_fs_inode_free(struct inode *inode)
  * Note that for purely virtual devices @parent can be NULL.
  *
  * RETURNS:
- * Pointer to new DRM device, or NULL if out of memory.
+ * 0 on success, or error code on failure.
  */
-struct drm_device *drm_dev_alloc(struct drm_driver *driver,
-				 struct device *parent)
+int drm_dev_init(struct drm_device *dev,
+		 struct drm_driver *driver,
+		 struct device *parent)
 {
-	struct drm_device *dev;
    int ret;
-	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
-	if (!dev)
-		return NULL;
-
    kref_init(&dev->ref);
    dev->dev = parent;
    dev->driver = driver;
@@ -638,7 +635,7 @@ struct drm_device *drm_dev_alloc(struct drm_driver *driver,
    		goto err_setunique;
    }
-	return dev;
+	return 0;
err_setunique:
    if (drm_core_check_feature(dev, DRIVER_GEM))
@@ -653,8 +650,46 @@ err_minors:
    drm_fs_inode_free(dev->anon_inode);
 err_free:
    mutex_destroy(&dev->master_mutex);
-	kfree(dev);
-	return NULL;
+	return 0;
+}
+EXPORT_SYMBOL(drm_dev_init);
+
+/**
+ * drm_dev_alloc - Allocate new DRM device
+ * @driver: DRM driver to allocate device for
+ * @parent: Parent device object
+ *
+ * Allocate and initialize a new DRM device. No device registration is done.
+ * Call drm_dev_register() to advertice the device to user space and register it
+ * with other core subsystems. This should be done last in the device
+ * initialization sequence to make sure userspace can't access an inconsistent
+ * state.
+ *
+ * The initial ref-count of the object is 1. Use drm_dev_ref() and
+ * drm_dev_unref() to take and drop further ref-counts.
+ *
+ * Note that for purely virtual devices @parent can be NULL.
+ *
+ * RETURNS:
+ * Pointer to new DRM device, or NULL if out of memory.
+ */
+struct drm_device *drm_dev_alloc(struct drm_driver *driver,
+				 struct device *parent)
+{
+	struct drm_device *dev;
+	int ret;
+
+	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+	if (!dev)
+		return NULL;
+
+	ret = drm_dev_init(dev, driver, parent);
+	if (ret) {
+		kfree(dev);
+		return NULL;
+	}
+
+	return dev;
 }
 EXPORT_SYMBOL(drm_dev_alloc);
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index c5d29505f937..12dc5f9cad89 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -1075,6 +1075,9 @@ extern void drm_sysfs_hotplug_event(struct drm_device *dev);
struct drm_device *drm_dev_alloc(struct drm_driver *driver,
    			 struct device *parent);
+int drm_dev_init(struct drm_device *dev,
+		 struct drm_driver *driver,
+		 struct device *parent);
 void drm_dev_ref(struct drm_device *dev);
 void drm_dev_unref(struct drm_device *dev);
 int drm_dev_register(struct drm_device *dev, unsigned long flags);
-- 
2.8.1


    