btrfs-progs: check: lowmem: introduce try_force_cow_in_new_chunk

Introduce create_chunk_and_block_block_group() to allocate a new chunk
and corresponding block group.

The new function force_cow_in_new_chunk() firstly allocates new chunk
and records its start.
Then it modifies all metadata block groups cached and full.
Finally it marks the new block group uncached and unfree.
In the next COW, extents states will be updated automatically by
cache_block_group().

New function try_to_force_cow_in_new_chunk() will try to mark block
groups full, allocate a new chunk and records the start.
If the last allocated chunk is almost full, a new chunk will be
allocated.

Suggested-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>

0 files changed, 0 insertions, 0 deletions