recent disk-related breakage

[Roger Pau Monné]

El 11/01/16 a les 7.47, Colin Percival ha escrit:
> I'm rather suspicious of r292255 here -- royger, hps, kib, can any of you
> comment on whether it would be responsible for making non-page-aligned I/Os
> no longer get split on page boundaries?  The commit message is suggestive,
> but I don't know the code very well.

Hello,

This is caused by r291716, which re-introduced the broken mechanism
found in bus_dmamap_load_ma_triv. I've already notified ken about it,
and I have a patch that should solve it by reverting to the usage of
_bus_dmamap_load_ma in order to load an unmapped bio:

https://lists.freebsd.org/pipermail/svn-src-all/2016-January/116629.html

Roger.