In the past there were a few kernel panics related to block reservation
tree operations failure (insert/remove etc).  It would be very useful to
get the block allocation reservation map info when such error happens.
Signed-off-by: NMingming Cao <cmm@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>