Because of some braindead hardware engineers, we need to map in some
high memory areas just to find out how much memory we have, and where it
is. (the e820 table doesn't cut it on this hardware)

I can't think of a good name for this.  It's earlier than bt_ioremap()
and super_mega_bt_ioremap() doesn't have much of a ring to it.

This is only intended for remapping while the boot-time pagetables are
still in use.  It was a pain to get the 2-level pgtable.h functions, so
I just undef'd CONFIG_X86_PAE for my file.  It looks awfully hackish,
but it works well.

Some of my colleagues prefer to steal ptes from some random source, then
replace them when the remapping is done, but I don't really like this
approach.  I prefer to know exactly where I'm stealing them from, which
is where boot_ioremap_area[] comes in.
-- 
Dave Hansen
haveblue@us.ibm.com