Btrfs: reduce stack usage in some crucial tree balancing functions

Many of the tree balancing functions follow the same pattern.

1) cow a block
2) do something to the result

This commit breaks them up into two functions so the variables and
code required for part two don't suck down stack during part one.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Chris Mason 2009-03-13 10:04:31 -04:00
commit 44871b1b24