Re: [PATCH 04/15] brd: remove dax support

[Jens Axboe]

On 10/31/2017 05:21 PM, Dan Williams wrote:
> DAX support in brd is awkward because its backing page frames are
> distinct from the ones provided by pmem, dcssblk, or axonram. We need
> pfn_t_devmap() entries to fully support DAX, and the limited DAX support
> for pfn_t_special() page frames is not interesting for brd when pmem is
> already a superset of brd.  Lastly, brd is the only dax capable driver
> that may sleep in its ->direct_access() implementation. So it causes a
> global burden with no net gain of kernel functionality.
> 
> For all these reasons, remove DAX support.

Reviewed-by: Jens Axboe <axboe@xxxxxxxxx>

-- 
Jens Axboe