btrfs: qgroup: correctly model root qgroup rsv in convert

commit 141fb8cd20 upstream.

We use add_root_meta_rsv and sub_root_meta_rsv to track prealloc and
pertrans reservations for subvolumes when quotas are enabled. The
convert function does not properly increment pertrans after decrementing
prealloc, so the count is not accurate.

Note: we check that the fs is not read-only to mirror the logic in
qgroup_convert_meta, which checks that before adding to the pertrans rsv.

Fixes: 8287475a20 ("btrfs: qgroup: Use root::qgroup_meta_rsv_* to record qgroup meta reserved space")
CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Boris Burkov 2024-03-19 10:54:22 -07:00 committed by Greg Kroah-Hartman
parent 23b57c5566
commit 773d38f42b
1 changed files with 2 additions and 0 deletions

View File

@ -4080,6 +4080,8 @@ void btrfs_qgroup_convert_reserved_meta(struct btrfs_root *root, int num_bytes)
BTRFS_QGROUP_RSV_META_PREALLOC);
trace_qgroup_meta_convert(root, num_bytes);
qgroup_convert_meta(fs_info, root->root_key.objectid, num_bytes);
if (!sb_rdonly(fs_info->sb))
add_root_meta_rsv(root, num_bytes, BTRFS_QGROUP_RSV_META_PERTRANS);
}
/*