btrfs: qgroup: Add new function to record old_roots.
Add function btrfs_qgroup_prepare_account_extents() to get old_roots
which are needed for qgroup.
We do it in commit_transaction() and before switch_roots(), and only
search commit_root, so it gives a quite accurate view for previous
transaction.
With old_roots from previous transaction, we can use it to do accurate
account with current transaction.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 55465d5..7b18fff 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -1553,6 +1553,33 @@
return 0;
}
+int btrfs_qgroup_prepare_account_extents(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_qgroup_extent_record *record;
+ struct btrfs_delayed_ref_root *delayed_refs;
+ struct rb_node *node;
+ int ret = 0;
+
+ delayed_refs = &trans->transaction->delayed_refs;
+
+ /*
+ * No need to do lock, since this function will only be called in
+ * btrfs_commmit_transaction().
+ */
+ node = rb_first(&delayed_refs->dirty_extent_root);
+ while (node) {
+ record = rb_entry(node, struct btrfs_qgroup_extent_record,
+ node);
+ ret = btrfs_find_all_roots(NULL, fs_info, record->bytenr, 0,
+ &record->old_roots);
+ if (ret < 0)
+ break;
+ node = rb_next(node);
+ }
+ return ret;
+}
+
struct btrfs_qgroup_extent_record
*btrfs_qgroup_insert_dirty_extent(struct btrfs_delayed_ref_root *delayed_refs,
struct btrfs_qgroup_extent_record *record)
diff --git a/fs/btrfs/qgroup.h b/fs/btrfs/qgroup.h
index e58155d0..6fe249f 100644
--- a/fs/btrfs/qgroup.h
+++ b/fs/btrfs/qgroup.h
@@ -98,6 +98,8 @@
u64 bytenr, u64 num_bytes,
enum btrfs_qgroup_operation_type type,
int mod_seq);
+int btrfs_qgroup_prepare_account_extents(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info);
struct btrfs_qgroup_extent_record
*btrfs_qgroup_insert_dirty_extent(struct btrfs_delayed_ref_root *delayed_refs,
struct btrfs_qgroup_extent_record *record);