this is a re-send of the max-sectors patch against 2.6.9-rc1-bk14.

the attached patch introduces two new /sys/block values:

  /sys/block/*/queue/max_hw_sectors_kb
  /sys/block/*/queue/max_sectors_kb

max_hw_sectors_kb is the maximum that the driver can handle and is
readonly. max_sectors_kb is the current max_sectors value and can be
tuned by root. PAGE_SIZE granularity is enforced.

It's all locking-safe and all affected layered drivers have been updated
as well. The patch has been in testing for a couple of weeks already as
part of the voluntary-preempt patches and it works just fine - people
use it to reduce IDE IRQ handling latencies. Please apply.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

	Ingo