Pull btrfs update frm Chris Mason:
"This is our usual merge window set of bug fixes, performance
improvements and cleanups. Miao Xie has some really nice
optimizations for writeback.
Josef also expanded our sanity checks quite a bit; these make up a big
chunk of the new lines"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (98 commits)
Btrfs: rename btrfs_start_all_delalloc_inodes
Btrfs: don't wait for the completion of all the ordered extents
Btrfs: don't wait for all the async delalloc when shrinking delalloc
Btrfs: fix the confusion between delalloc bytes and metadata bytes
Btrfs: pick up the code for the item number calculation in flush_space()
Btrfs: wait for the ordered extent only when we want
Btrfs: remove unnecessary initialization and memory barrior in shrink_delalloc()
Btrfs: avoid unnecessary scrub workers allocation
Btrfs: check file extent type before anything else
btrfs: Remove useless variable in write_ctree_super()
btrfs: Fix checkpatch.pl warning of spacing issues
btrfs: Replace kmalloc with kmalloc_array
btrfs: Enclose macros with complex values within parenthesis
btrfs: Use WARN_ON()'s return value in place of WARN_ON(1)
btrfs: Remove redundant local zero structure
btrfs: Pack struct btrfs_device
btrfs: Replace multiple atomic_inc() with atomic_add()
btrfs: Add helper function for free_root_pointers()
Btrfs: fix a crash when running balance and defrag concurrently
Btrfs: do not run snapshot-aware defragment on error
...