I2O subsystem has been broken in mainstream several months ago (after
2.6.18).  Commit 4aff5e23

 from Jens
Axboe split struct request ->flags into two parts: cmd_type and
cmd_flags.

In i2o layer this patch has replaced flag REQ_SPECIAL by the according
cmd_type.  However i2o has used REQ_SPECIAL not as command type but as
driver-specific flag for the debug purposes.  As result all i2o requests
have type "special" now, are not processed to the hardware and fail with
I/O error:

   i2o/hda:<3>Buffer I/O error on device i2o/hda, logical block 0
  Buffer I/O error on device i2o/hda, logical block 0
  Buffer I/O error on device i2o/hda, logical block 0
   unable to read partition table
  block-osm: device added (TID: 207): i2o/hda

The following patch removes the extra debug checks without any drawbacks and
restores the normal driver's work.

Signed-off-by: Vasily Averin <vvs@sw.ru>
Acked-by: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>