Re: [dm-devel] [PATCH] multipath: Evaluate request result and sense code

[Hannes Reinecke <hare suse de>]

Mike Christie wrote:
> Hannes Reinecke wrote:
>>  /*
>> + * Evaluate scsi return code
>> + */
>> +static int eval_scsi_error(int result, char *sense, int sense_len)
>> +{
>> +    struct scsi_sense_hdr sshdr;
>> +    int r = DM_ENDIO_REQUEUE;
>> +
>> +    if (host_byte(result) != DID_OK)
> 
> 
> For values like DID_NO_CONNECT or DID_TRANSPORT FAILFAST, I think it
> makes sense to fail the path. Not in this patch, but a new one, would we
> want to modify dm-mpath so that we do not fail the path for errors like
> DID_ABORT or DID_SOFT_ERROR, DID_RESET or DID_ERROR?
Yeah, well, this patch was made to model the existing behaviour closely
so as the patch submission was not blocked by irrelevant side discussions ...

But yes, of course we should be a bit more selective on how to respond
to the various error codes. But this requires some more discussion with
the various vendors as things like 'DID_ERROR' have different meanings
for different HBAs ...

But this should be done once we agreed on the principle, ie on _how_
to pass the error codes up the the multipathing layer.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		      zSeries & Storage
hare suse de			      +49 911 74053 688
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