[dm-devel] [RFC PATCH 0/4] add new block layer error values

[Mike Christie <michaelc cs wisc edu>]

The current -Exyz errors are not descriptive enough to allow upper
layers like DM and MD to decide how to handle IO errors. In many cases
all we get is a -EIO. The following patches introduce block layer error
values for use with the bio_endio and end_that_request* functions
(end_request keeps uptodate).

This is just as a RFC I am still testing and working on them and am
hoping to get some comments. All patches were made against the
scsi-misc-2.6 tree.