This reverts commit 0c0b3ae6.

Quoth David:

  "Jeff, please revert

   It's wrong.  We had a lengthy analysis of this piece of code
   several months ago, and it is correct.

   Consider, if we run the loop and we get an error
   the following happens:

   1) attempt of ifb_init_one(i) fails, therefore we should
      not try to "ifb_free_one()" on "i" since it failed
   2) the loop iteration first increments "i", then it
      check for error

   Therefore we must decrement "i" twice before the first
   free during the cleanup.  One to "undo" the for() loop
   increment, and one to "skip" the ifb_init_one() case which
   failed."
Reported-by: David Miller <davem@davemloft.net>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Cc: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>