tree 1116ac2cb55448e8ababe86ce1535c2d376723b4
parent 524725537023bb25a371722b1329446e5a2adcdb
author Qu Wenruo <quwenruo@cn.fujitsu.com> 1444638486 +0800
committer Chris Mason <clm@fb.com> 1445477866 -0700

btrfs: qgroup: Introduce functions to release/free qgroup reserve data
space

Introduce functions btrfs_qgroup_release/free_data() to release/free
reserved data range.

Release means, just remove the data range from io_tree, but doesn't
free the reserved space.
This is for normal buffered write case, when data is written into disc
and its metadata is added into tree, its reserved space should still be
kept until commit_trans().
So in that case, we only release dirty range, but keep the reserved
space recorded some other place until commit_tran().

Free means not only remove data range, but also free reserved space.
This is used for case for cleanup and invalidate page.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>