Why does this matter? From my understanding, v4l2_fh is meant to be embed it in a device specific structure. If it is the first member in the device specific structure, then the pointer to v4l2_fh is the same as the one to the device specific structure. Otherwise, a simple container_of can be used to calculate the appropriate address of the container. In either case, the pointer calculation method is always going to be faster than executing a call, and de-referencing multiple pointers to retrieve the same information. filp->private data is there for a reason, why not use it as intended and avoid the additional overhead added by this patch? Regards, David Ellingsworth -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html