staging/android: remove driver_data from struct sync_fence_info

It is unclear in what situations driver_data should be used thus better do
not upstream it for now. If a need arises in the future a discussion can
be started to re-add it.
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/android/sw_sync.c

@@ -47,19 +47,6 @@ static int sw_sync_fence_has_signaled(struct fence *fence)
 	return (pt->value > obj->value) ? 0 : 1;
 }
 
-static int sw_sync_fill_driver_data(struct fence *fence,
-				    void *data, int size)
-{
-	struct sw_sync_pt *pt = (struct sw_sync_pt *)fence;
-
-	if (size < sizeof(pt->value))
-		return -ENOMEM;
-
-	memcpy(data, &pt->value, sizeof(pt->value));
-
-	return sizeof(pt->value);
-}
-
 static void sw_sync_timeline_value_str(struct sync_timeline *sync_timeline,
 				       char *str, int size)
 {
@@ -78,7 +65,6 @@ static void sw_sync_fence_value_str(struct fence *fence, char *str, int size)
 static struct sync_timeline_ops sw_sync_timeline_ops = {
 	.driver_name = "sw_sync",
 	.has_signaled = sw_sync_fence_has_signaled,
-	.fill_driver_data = sw_sync_fill_driver_data,
 	.timeline_value_str = sw_sync_timeline_value_str,
 	.fence_value_str = sw_sync_fence_value_str,
 };

drivers/staging/android/sync.c

@@ -351,16 +351,6 @@ static bool android_fence_enable_signaling(struct fence *fence)
 	return true;
 }
 
-static int android_fence_fill_driver_data(struct fence *fence,
-					  void *data, int size)
-{
-	struct sync_timeline *parent = fence_parent(fence);
-
-	if (!parent->ops->fill_driver_data)
-		return 0;
-	return parent->ops->fill_driver_data(fence, data, size);
-}
-
 static void android_fence_value_str(struct fence *fence,
 				    char *str, int size)
 {
@@ -394,7 +384,6 @@ static const struct fence_ops android_fence_ops = {
 	.signaled = android_fence_signaled,
 	.wait = fence_default_wait,
 	.release = android_fence_release,
-	.fill_driver_data = android_fence_fill_driver_data,
 	.fence_value_str = android_fence_value_str,
 	.timeline_value_str = android_fence_timeline_value_str,
 };
@@ -493,22 +482,12 @@ static long sync_file_ioctl_merge(struct sync_file *sync_file,
 static int sync_fill_fence_info(struct fence *fence, void *data, int size)
 {
 	struct sync_fence_info *info = data;
-	int ret;
 
 	if (size < sizeof(*info))
 		return -ENOMEM;
 
 	info->len = sizeof(*info);
 
-	if (fence->ops->fill_driver_data) {
-		ret = fence->ops->fill_driver_data(fence, info->driver_data,
-						   size - sizeof(*info));
-		if (ret < 0)
-			return ret;
-
-		info->len += ret;
-	}
-
 	strlcpy(info->obj_name, fence->ops->get_timeline_name(fence),
 		sizeof(info->obj_name));
 	strlcpy(info->driver_name, fence->ops->get_driver_name(fence),

drivers/staging/android/sync.h

@@ -32,10 +32,6 @@ struct sync_file;
  *			  1 if pt has signaled
  *			  0 if pt has not signaled
  *			 <0 on error
- * @fill_driver_data:	write implementation specific driver data to data.
- *			  should return an error if there is not enough room
- *			  as specified by size.  This information is returned
- *			  to userspace by SYNC_IOC_FENCE_INFO.
  * @timeline_value_str: fill str with the value of the sync_timeline's counter
  * @fence_value_str:	fill str with the value of the fence
  */
@@ -45,9 +41,6 @@ struct sync_timeline_ops {
 	/* required */
 	int (*has_signaled)(struct fence *fence);
 
-	/* optional */
-	int (*fill_driver_data)(struct fence *fence, void *data, int size);
-
 	/* optional */
 	void (*timeline_value_str)(struct sync_timeline *timeline, char *str,
 				   int size);

drivers/staging/android/uapi/sync.h

@@ -28,12 +28,11 @@ struct sync_merge_data {
 
 /**
  * struct sync_fence_info - detailed fence information
- * @len:		length of sync_fence_info including any driver_data
+ * @len:		length of sync_fence_info
  * @obj_name:		name of parent sync_timeline
  * @driver_name:	name of driver implementing the parent
  * @status:		status of the fence 0:active 1:signaled <0:error
  * @timestamp_ns:	timestamp of status change in nanoseconds
- * @driver_data:	any driver dependent data
  */
 struct sync_fence_info {
 	__u32	len;
@@ -41,8 +40,6 @@ struct sync_fence_info {
 	char	driver_name[32];
 	__s32	status;
 	__u64	timestamp_ns;
-
-	__u8	driver_data[0];
 };
 
 /**