Merge tag 'for-5.6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Merge tag 'for-5.6-tag' of git://git./linux/kernel/git/kdave/linux

Pull more btrfs updates from David Sterba:
 "Fixes that arrived after the merge window freeze, mostly stable
  material.

   - fix race in tree-mod-log element tracking

   - fix bio flushing inside extent writepages

   - fix assertion when in-memory tracking of discarded extents finds an
     empty tree (eg. after adding a new device)

   - update logic of temporary read-only block groups to take into
     account overcommit

   - fix some fixup worker corner cases:
       - page could not go through proper COW cycle and the dirty status
         is lost due to page migration
       - deadlock if delayed allocation is performed under page lock

   - fix send emitting invalid clones within the same file

   - fix statfs reporting 0 free space when global block reserve size is
     larger than remaining free space but there is still space for new
     chunks"

* tag 'for-5.6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: do not zero f_bavail if we have available space
  Btrfs: send, fix emission of invalid clone operations within the same file
  btrfs: do not do delalloc reservation under page lock
  btrfs: drop the -EBUSY case in __extent_writepage_io
  Btrfs: keep pages dirty when using btrfs_writepage_fixup_worker
  btrfs: take overcommit into account in inc_block_group_ro
  btrfs: fix force usage in inc_block_group_ro
  btrfs: Correctly handle empty trees in find_first_clear_extent_bit
  btrfs: flush write bio if we loop in extent_write_cache_pages
  Btrfs: fix race between adding and putting tree mod seq elements and nodes