Op 03-03-16 om 15:34 schreef Gustavo Padovan: > From: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxxxx> > > Change SYNC_IOC_FILE_INFO behaviour to avoid future API breaks and > optimize buffer > > Now num_fences can be filled by the caller to inform how many fences it > wants to retrieve from the kernel. If the num_fences passed is greater > than zero info->sync_fence_info should point to a buffer with enough space > to fit all fences. > > However if num_fences passed to the kernel is 0, the kernel will reply > with number of fences of the sync_file. > > Sending first an ioctl with num_fences = 0 can optimize buffer allocation, > in a first call with num_fences = 0 userspace will receive the actual > number of fences in the num_fences filed. > > Then it can allocate a buffer with the correct size on sync_fence_info and > call SYNC_IOC_FILE_INFO again, but now with the actual value of num_fences > in the sync_file. > > Also, info->sync_fence_info was converted to __u64 pointer to prevent > 32bit compatibility issues. For this patch and 6/6: Reviewed-by: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx> _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
