Re: [PATCH v12 4/7] dm: enable synchronous dax

From: Mike Snitzer
Date: Tue Jun 11 2019 - 13:19:18 EST


On Tue, Jun 11 2019 at 12:37pm -0400,
Pankaj Gupta <pagupta@xxxxxxxxxx> wrote:

> This patch sets dax device 'DAXDEV_SYNC' flag if all the target
> devices of device mapper support synchrononous DAX. If device
> mapper consists of both synchronous and asynchronous dax devices,
> we don't set 'DAXDEV_SYNC' flag.
>
> 'dm_table_supports_dax' is refactored to pass 'iterate_devices_fn'
> as argument so that the callers can pass the appropriate functions.
>
> Suggested-by: Mike Snitzer <snitzer@xxxxxxxxxx>
> Signed-off-by: Pankaj Gupta <pagupta@xxxxxxxxxx>

Thanks, and for the benefit of others, passing function pointers like
this is perfectly fine IMHO because this code is _not_ in the fast
path. These methods are only for device creation.

Reviewed-by: Mike Snitzer <snitzer@xxxxxxxxxx>