Git tree updates

[Matthew Wilcox]

Hey, just wanted to let people know that Linus pulled the fixes that I
asked him to last week.  They're in 3.9-rc4.

I had some time on an aeroplane today, and I merged two major features;
the discard support and SCSI emulation.  Those are available in the public
git tree now.  I have some more time on an aeroplane this evening, so I'll
be looking at merging some more patches and pushing those out tomorrow.