Btrfs changes from vfs.git

Hi Linus,

This is pull request #2 of 2, and it's actually for a branch off Al's tree.

git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git btrfs

There's one minor conflict in the ioctl.c, which I've resolved here:

git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs.git viro

I did the split pull like this because Al's changes are on 3.3-pre-rc and the rest of my stuff is on 3.2. But I did test Al's code against the your current master.

Al Viro (16) commits:

    btrfs: kill pointless reassignment of ->s_fs_info in btrfs_fill_super() (+2/-5)
    btrfs: make free_fs_info() call ->kill_sb() unconditional (+2/-6)
    btrfs: take allocation of ->tree_root into open_ctree() (+5/-10)
    btrfs: consolidate failure exits in btrfs_mount() a bit (+5/-16)
    btrfs: merge free_fs_info() calls on fill_super failures (+1/-3)
    btrfs: let ->s_fs_info point to fs_info, not root... (+45/-45)
    btrfs: fix a deadlock in btrfs_scan_one_device() (+2/-3)
    btrfs: preparation to fixing mount/umount race (+6/-3)
    btrfs: make open_ctree() return int (+13/-13)
    btrfs: sanitizing ->fs_info, part 5 (+11/-11)
    btrfs: sanitizing ->fs_info, part 4 (+18/-20)
    btrfs: sanitizing ->fs_info, part 3 (+5/-7)
    btrfs: sanitizing ->fs_info, part 2 (+4/-1)
    btrfs: sanitizing ->fs_info, part 1 (+6/-1)
    btrfs: get ->kill_sb() of its own (+18/-9)
    btrfs: fix mount/umount race (+4/-9)

Total: (16) commits (+110/-125)

 fs/btrfs/ctree.h   |    2 +-
 fs/btrfs/disk-io.c |   70 +++++++++++++------------
 fs/btrfs/disk-io.h |    6 +-
 fs/btrfs/export.c  |    2 +-
 fs/btrfs/ioctl.c   |    7 +--
 fs/btrfs/super.c   |  143 +++++++++++++++++++++++-----------------------------
 fs/btrfs/volumes.c |    5 +-
 7 files changed, 110 insertions(+), 125 deletions(-)