4.14-stable review patch. If anyone has any objections, please let me know.
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From: Justin Maggard jmaggard10@gmail.com
[ Upstream commit b430b7751286b3acff2d324553c8cec4f1e87764 ]
Commit c6887cd11149 ("Btrfs: don't do nocow check unless we have to") changed the behavior of __btrfs_buffered_write() so that it first tries to get a data space reservation, and then skips the relatively expensive nocow check if the reservation succeeded.
If we have quotas enabled, the data space reservation also includes a quota reservation. But in the rewrite case, the space has already been accounted for in qgroups. So btrfs_check_data_free_space() increases the quota reservation, but it never gets decreased when the data actually gets written and overwrites the pre-existing data. So we're left with both the qgroup and qgroup reservation accounting for the same space.
This commit adds the missing btrfs_qgroup_free_data() call in the case of BTRFS_ORDERED_PREALLOC extents.
Fixes: c6887cd11149 ("Btrfs: don't do nocow check unless we have to") Signed-off-by: Justin Maggard jmaggard@netgear.com Reviewed-by: Qu Wenruo wqu@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/btrfs/inode.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -3016,6 +3016,8 @@ static int btrfs_finish_ordered_io(struc compress_type = ordered_extent->compress_type; if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) { BUG_ON(compress_type); + btrfs_qgroup_free_data(inode, NULL, ordered_extent->file_offset, + ordered_extent->len); ret = btrfs_mark_extent_written(trans, BTRFS_I(inode), ordered_extent->file_offset, ordered_extent->file_offset +