tree b03fb64eb4567d1d1320a43f5d2142bc65193c18
parent 4a09675279674041862d2210635b0cc1f60be28e
author Chris Mason <chris.mason@oracle.com> 1216739887 -0400
committer Chris Mason <chris.mason@oracle.com> 1222355045 -0400

Btrfs: Index extent buffers in an rbtree

Before, extent buffers were a temporary object, meant to map a number of pages
at once and collect operations on them.

But, a few extra fields have crept in, and they are also the best place to
store a per-tree block lock field as well.  This commit puts the extent
buffers into an rbtree, and ensures a single extent buffer for each
tree block.

Signed-off-by: Chris Mason <chris.mason@oracle.com>