Re: [PATCH v3 1/2] ext4: Pass in DIO_SKIP_DIO_COUNT flag if inode_dio_begin() called

[Waiman Long]

On 04/20/2016 04:58 PM, Christoph Hellwig wrote:
> FYI, none of the Dax code even needs to ever touch the dio_count,
> as dax I/O can't be asynchronous, and we thus don't need it to protect
> against truncate.  I'd suggest to remove it and then end_io callback
> from the DAX code entirely as a start and then move from there.

Yes, it seems like we may not need to change the dio_count in 
dax_do_io() after all. BTW, what do mean by using end_io callback as a 
start?

Cheers,
Longman