Here's a set of patches that do some tidying in the btree remove code and
fix an issue that caused under populated nodes.
Tested on my system, more testing required before pushing upstream.
Joe Thornber (5):
[dm-thin] Remove redundant arg from value_ptr()
[dm-thin] Remove 2 BUG_ONs from btree_remove code.
[dm-thin] [btree-remove] break up __rebalance3 function.
[dm-thin] [btree-remove] Fix bug that allowed the nr of entries in a
btree node to drop below 1/3.
[dm-thin] [space-map-common] Remove entries from the ref_count tree
if they're no longer needed.