Pull the minimal btrfs branch from Chris Mason:
 "We have a use-after-free in there, along with errors when mount -o
  discard is enabled, and a BUG_ON(we should compile with UP more
  often)."

* 'for-linus-min' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: use commit root when loading free space cache
  Btrfs: fix use-after-free in __btrfs_end_transaction
  Btrfs: check return value of bio_alloc() properly
  Btrfs: remove lock assert from get_restripe_target()
  Btrfs: fix eof while discarding extents
  Btrfs: fix uninit variable in repair_eb_io_failure
  Revert "Btrfs: increase the global block reserve estimates"