[Cluster-devel] RFC: use the iomap writepage path in gfs2

[Dave Chinner <david@fromorbit.com>]

On Mon, Jul 01, 2019 at 11:54:24PM +0200, Christoph Hellwig wrote:
> Hi all,
> 
> in this straight from the jetplane edition I present the series to
> convert gfs2 to full iomap usage for the ordered and writeback mode,
> that is we use iomap_page everywhere and entirely get rid of
> buffer_heads in the data path.  This has only seen basic testing
> which ensured neither 4k or 1k blocksize in ordered mode regressed
> vs the xfstests baseline, although that baseline tends to look
> pretty bleak.
> 
> The series is to be applied on top of my "lift the xfs writepage code
> into iomap v2" series.

Ok, this doesn't look too bad from the iomap perspective, though it
does raise more questions. :)

gfs2 now has two iopaths, right? One that uses bufferheads for
journalled data, and the other that uses iomap? That seems like it's
only a partial conversion - what needs to be done to iomap and gfs2
to support the journalled data path so there's a single data IO
path?

Cheers,

Dave.
-- 
Dave Chinner
david at fromorbit.com