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

[Christoph Hellwig]

On Mon, Jun 28, 2021 at 04:57:33PM +0200, Martin Wilck wrote:
> 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?

Not by exporting random crap from the SCSI code.