Ingo chamged it again 8)

Looks like they escaped your notice

Yes this is big but 2.4 has been indented, updated and there wasnt a
sane way to deal with it

There are some bits left to do but this folds in all the main stuff from
2.4 and 2.5 including Al's recent change

This doesnt fix all the isdn code but it sorts out the tqueue stuff so we
are no worse than before

Linus, this has been tested by some people in the field to not break
things, and it's the start of some other changes I'm making, so please put
this in your tree so I'm not merging huge patches but instead am merging a
little as I go.

This enables tagged command queueing support in the ide layer again and
marks it as an experimental feature.

This changes the way we do pool lookups when freeing a bio.  Right now
we use bi_max as a handle into bvec_array[], to find the pool where it
came from.  This used to be just fine, because if you had a private bio,
you could specify your own destructor.  But now we have bio_add_page()
which also needs to know where the bio came from, or more precisely, it
needs to know how many entries the bio can hold.

So I've changed bi_max to bi_max_vecs, it now contains the number of vec
entries in the bio. Privately allocated bio's (or on stack) can now just
set bio->bi_max_vecs to reflect the max size. The pool index for the
default destructor is stored in the top bits of bi_flags.

Make things static, and remove hardcoded value

As per comment..

Hide ISA only drivers during configuration..

From Pavel Machek. Without these two lines,
the throttling limits are never reached, and a machine
will happily cook itself.