[PATCH 3/9] xfs: rework xfs_buf_bio_endio error handling

[Christoph Hellwig]

On Fri, Aug 15, 2014 at 04:39:01PM +1000, Dave Chinner wrote:
> In doing so, allow xfs_buf_iorequest to return an error. That way,
> the caller can check for submission errors safely if required, and
> easily distinguish them from completion errors that come from
> xfs_buf_iowait().

While this looks correct to me it also looks confusing.  Why can't
we simply propagat the submission errors through error returns
and use ->b_error for completion errors instead?