Btrfs: misc fixes for 4.5

here's a collection of patches from the mailinglist that do not appear in the integratin-4.5 branch. There are fixes or misc changes and improvements.

Please consider for 4.5. Thanks.

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The following changes since commit 4ef7675344d687a0ef5b0d7c0cee12da005870c0:

Linux 4.4-rc6 (2015-12-20 16:06:09 -0800)

are available in the git repository at:

git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux.git misc-for-4.5

for you to fetch changes up to ee592d07716139ef7c3ea8049936cbc3aafbc533:

Btrfs: Check metadata redundancy on balance (2016-01-07 15:20:56 +0100)

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Anand Jain (1):
Btrfs: add missing brelse when superblock checksum fails

David Sterba (17):
btrfs: put delayed item hook into inode
btrfs: better packing of btrfs_delayed_extent_op
btrfs: handle invalid num_stripes in sys_array
btrfs: verbose error when we find an unexpected item in sys_array
btrfs: drop duplicate prefix from scrub workqueues
btrfs: don't use slab cache for struct btrfs_delalloc_work btrfs tests: replace whole ops structure for free space tests
btrfs: constify remaining structs with function pointers
btrfs: constify static arrays
btrfs: cleanup, use enum values for btrfs_path reada
btrfs: use smaller type for btrfs_path reada
btrfs: use smaller type for btrfs_path lowest_level
btrfs: use smaller type for btrfs_path locks
btrfs: do an allocation earlier during snapshot creation
btrfs: allocate root item at snapshot ioctl time
btrfs: preallocate path for snapshot creation at ioctl time
btrfs: statfs: report zero available if metadata are exhausted

Josef Bacik (1):
Btrfs: igrab inode in writepage

Sam Tygier (1):
Btrfs: Check metadata redundancy on balance

Zhao Lei (1):
btrfs: Support convert to -d dup for btrfs-convert

 fs/btrfs/btrfs_inode.h            |   4 ++
 fs/btrfs/ctree.c                  |   9 ++--
 fs/btrfs/ctree.h                  |   9 ++--
 fs/btrfs/delayed-ref.c            |   4 +-
 fs/btrfs/delayed-ref.h            |   8 +--
 fs/btrfs/disk-io.c                |   1 +
 fs/btrfs/extent-tree.c            |  27 +++++-----
 fs/btrfs/extent-tree.h            |   0
 fs/btrfs/file-item.c              |   4 +-
 fs/btrfs/free-space-cache.c       |   2 +-
 fs/btrfs/free-space-cache.h       |   2 +-
 fs/btrfs/inode-map.c              |   6 +--
 fs/btrfs/inode.c                  | 101 ++++++++++++++++++--------------------
 fs/btrfs/ioctl.c                  |  35 ++++++++-----
 fs/btrfs/relocation.c             |  12 ++---
 fs/btrfs/scrub.c                  |  12 ++---
 fs/btrfs/super.c                  |  26 +++++++++-
 fs/btrfs/tests/free-space-tests.c |  14 +++---
 fs/btrfs/transaction.c            |  18 +++----
 fs/btrfs/transaction.h            |   2 +
 fs/btrfs/volumes.c                |  32 +++++++-----
 fs/btrfs/xattr.c                  |   2 +-
 22 files changed, 186 insertions(+), 144 deletions(-)
 delete mode 100644 fs/btrfs/extent-tree.h