Please make sure you CC linux-block if you add block device ops. On Fri, Oct 25, 2019 at 01:21:42PM +0200, Michal Suchanek wrote: > Opening a block device may require a long operation such as waiting for > the cdrom tray to close. Performing this operation with locks held locks > out other attempts to open the device. These processes waiting to open > the device are not killable. > > To avoid this issue and still be able to perform time-consuming checks > at open() time the block device driver can provide open_finish(). If it > does opening the device proceeds even when an error is returned from > open(), bd_mutex is released and open_finish() is called. If > open_finish() succeeds the device is now open, if it fails release() is > called. > > When -ERESTARTSYS is returned from open() blkdev_get may loop without > calling open_finish(). On -ERESTARTSYS open_finish() is not called. > > Move a ret = 0 assignment up in the if/else branching to avoid returning > -ENXIO. Previously the return value was ignored on the unhandled branch. Still a complete nack for splitting a fundamental operation over two ops, especially just for working around a piece of buggy software.
