[dm-devel] [RFC] training mpath to discern between SCSI errors

[Sergei Shtylyov]

Hello.

Hannes Reinecke wrote:

> Actually, I think we have two separate issues here:
> 1) The need of having more detailed I/O errors even in the fs layer. This
>    we've already discussed at the LSF, consensus here is to allow other
>    errors than just 'EIO'.
>    Instead of Mike's approach I would rather use existing error codes here;
>    this will make the transition somewhat easier.
>    Initially I would propose to return 'ENOLINK' for a transport failure,
>    'EIO' for a non-retryable failure on the target, and 'ENODEV' for a
>    retryable failure on the target.

    Are you sure it's not vice versa: EIO for retryable and ENODEV for 
non-retryable failures. ENODEV looks more like permanent condition to me.

WBR, Sergei