btrfs: qgroup: Add function qgroup_update_refcnt().

This function is used to update refcnt for qgroups.
And is one of the two core functions used in the new qgroup implement.

This is based on the old update_old/new_refcnt, but provides a unified
logic and behavior.

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 26f9da26e17e15251d988b34e15dc377de2d0b37..81773176d01f6b90db1b8ac1279d764d775b7ee5 100644 (file)
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -1806,6 +1806,64 @@ static int qgroup_calc_new_refcnt(struct btrfs_fs_info *fs_info,
        return 0;
 }
 
+#define UPDATE_NEW     0
+#define UPDATE_OLD     1
+/*
+ * Walk all of the roots that points to the bytenr and adjust their refcnts.
+ */
+static int qgroup_update_refcnt(struct btrfs_fs_info *fs_info,
+                               struct ulist *roots, struct ulist *tmp,
+                               struct ulist *qgroups, u64 seq, int update_old)
+{
+       struct ulist_node *unode;
+       struct ulist_iterator uiter;
+       struct ulist_node *tmp_unode;
+       struct ulist_iterator tmp_uiter;
+       struct btrfs_qgroup *qg;
+       int ret = 0;
+
+       if (!roots)
+               return 0;
+       ULIST_ITER_INIT(&uiter);
+       while ((unode = ulist_next(roots, &uiter))) {
+               qg = find_qgroup_rb(fs_info, unode->val);
+               if (!qg)
+                       continue;
+
+               ulist_reinit(tmp);
+               ret = ulist_add(qgroups, qg->qgroupid, ptr_to_u64(qg),
+                               GFP_ATOMIC);
+               if (ret < 0)
+                       return ret;
+               ret = ulist_add(tmp, qg->qgroupid, ptr_to_u64(qg), GFP_ATOMIC);
+               if (ret < 0)
+                       return ret;
+               ULIST_ITER_INIT(&tmp_uiter);
+               while ((tmp_unode = ulist_next(tmp, &tmp_uiter))) {
+                       struct btrfs_qgroup_list *glist;
+
+                       qg = u64_to_ptr(tmp_unode->aux);
+                       if (update_old)
+                               btrfs_qgroup_update_old_refcnt(qg, seq, 1);
+                       else
+                               btrfs_qgroup_update_new_refcnt(qg, seq, 1);
+                       list_for_each_entry(glist, &qg->groups, next_group) {
+                               ret = ulist_add(qgroups, glist->group->qgroupid,
+                                               ptr_to_u64(glist->group),
+                                               GFP_ATOMIC);
+                               if (ret < 0)
+                                       return ret;
+                               ret = ulist_add(tmp, glist->group->qgroupid,
+                                               ptr_to_u64(glist->group),
+                                               GFP_ATOMIC);
+                               if (ret < 0)
+                                       return ret;
+                       }
+               }
+       }
+       return 0;
+}
+
 /*
  * This adjusts the counters for all referenced qgroups if need be.
  */