[dm-devel] [PATCH v4 1/3] scsi: scsi_ioctl: export __scsi_result_to_blk_status()

[Martin Wilck]

Hello Christoph,

On Mo, 2021-06-28 at 11:53 +0200, Christoph Hellwig wrote:
> On Mon, Jun 28, 2021 at 11:52:08AM +0200, mwilck at suse.com wrote:
> > From: Martin Wilck <mwilck at suse.com>
> > 
> > This makes it possible to use scsi_result_to_blk_status() from
> > code that shouldn't depend on scsi_mod (e.g. device mapper).
> 
> This really has no business being used outside of low-level SCSI
> code.

And this is where my patch set uses it. Can you recommend a better
way how to access this algorithm, without making dm_mod.ko or dm-
mpath.ko depend on scsi_mod.ko, and without open-coding it
independently in a different code path?

The sg_io-on-multipath code needs to answer the question "is this a
path or a target error?". Therefore it calls blk_path_error(), which
requires obtaining a blk_status_t first. But that's not available in
the sg_io code path. So how should I deal with this situation?

The first approach - inlining scsi_result_to_blk_status() - has been
rejected before.

Regards,
Martin