Re: [PATCH v2 01/11] dma-buf/sync_file: de-stage sync_file

From: Maarten Lankhorst
Date: Wed Jan 27 2016 - 09:31:14 EST


Op 27-01-16 om 14:30 schreef Gustavo Padovan:
> From: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxxxx>
> sync_file is useful to connect one or more fences to the file. The file is
> used by userspace to track fences.
> Signed-off-by: Gustavo Padovan <gustavo.padovan@xxxxxxxxxxxxxxx>
Is there a value in keeping the abi unchanged?
If not, then Documentation/ioctl/botching-up-ioctls.txt is worth a read.

Looking at the patch, it seems you kept SYNC_IOC_WAIT, won't it be better to remove it, and only support waiting with polling?
The code for polling should already work.

It's very unclear what format @driver_data has. I kept it for compatibility with android, but it's not clear to me how a userspace consumer would print it.
Is there a usecase for this, or could it be removed from fence and sync_file?