[dm-devel] Re: [RFC PATCH 1/4] convert block layer drivers to blkerr error values
Mike Christie
michaelc at cs.wisc.edu
Wed Aug 24 20:50:45 UTC 2005
James Bottomley wrote:
> On Wed, 2005-08-24 at 12:21 -0700, Patrick Mansfield wrote:
>
>>On Wed, Aug 24, 2005 at 04:03:58AM -0500, Mike Christie wrote:
>>
>>
>>>-#define end_io_error(uptodate) (unlikely((uptodate) <= 0))
>>>+enum {
>>>+ BLK_SUCCESS = 0, /* Must be zero for compat with old usage */
>>>+ BLKERR_IO, /* Generic I/O error */
>>>+ BLKERR_NOTSUPP, /* Operation is not supported */
>>>+ BLKERR_WOULDBLOCK, /* Operation would block */
>>>+ BLKERR_FATAL_DRV, /* Fatal driver error */
>>>+ BLKERR_FATAL_DEV, /* Fatal device error */
>>>+ BLKERR_FATAL_XPT, /* Fatal transport error */
>>>+ BLKERR_RETRY_DRV, /* Driver error, I/O may be retried */
>>>+ BLKERR_RETRY_DEV, /* Device error, I/O may be retried */
>>>+ BLKERR_RETRY_XPT, /* Transport error, I/O may retried */
>>>+};
>
>
> Actually, I'd really be happier if these were a bitmap rather than an
> enumeration. That way we can divide them easily into cause (Driver,
> Device or Transport) and severity (fatal or retryable), so something
> like dm-multipath would only be interested in errors it made sense for a
> path to be failed over for (i.e. all transport and driver errors).
>
Would it be good then to also extend the fail fast flag to a bit map so
dm-multipath can tell scsi that scsi should handle device errors?
More information about the dm-devel
mailing list