tree c9f062c00713267ecd5e2e62fc1dd41063fa1426
parent 1e144fb8f4a4d6d6d88c58f87e4366e3cd02ab72
author Omar Sandoval <osandov@fb.com> 1443585038 -0700
committer Chris Mason <clm@fb.com> 1450383407 -0800

Btrfs: add free space tree mount option

Now we can finally hook up everything so we can actually use free space
tree. The free space tree is enabled by passing the space_cache=v2 mount
option. On the first mount with the this option set, the free space tree
will be created and the FREE_SPACE_TREE read-only compat bit will be
set. Any time the filesystem is mounted from then on, we must use the
free space tree. The clear_cache option will also clear the free space
tree.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>