btrfs: qgroup: Make snapshot accounting work with new extent-oriented

qgroup.

Make snapshot accounting work with new extent-oriented mechanism by
skipping given root in new/old_roots in create_pending_snapshot().

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

1 files changed, 33 insertions, 20 deletions

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 3e3793dcb4c2..c0f18e7266b6 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -1295,6 +1295,12 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
         if (pending->error)
                 goto no_free_objectid;
 
+        /*
+         * Make qgroup to skip current new snapshot's qgroupid, as it is
+         * accounted by later btrfs_qgroup_inherit().
+         */
+        btrfs_set_skip_qgroup(trans, objectid);
+
         btrfs_reloc_pre_snapshot(trans, pending, &to_reserve);
 
         if (to_reserve > 0) {
@@ -1303,7 +1309,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
                                                      to_reserve,
                                                      BTRFS_RESERVE_NO_FLUSH);
                 if (pending->error)
-                        goto no_free_objectid;
+                        goto clear_skip_qgroup;
         }
 
         key.objectid = objectid;
@@ -1401,25 +1407,6 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
                 btrfs_abort_transaction(trans, root, ret);
                 goto fail;
         }
-
-        /*
-         * We need to flush delayed refs in order to make sure all of our quota
-         * operations have been done before we call btrfs_qgroup_inherit.
-         */
-        ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
-        if (ret) {
-                btrfs_abort_transaction(trans, root, ret);
-                goto fail;
-        }
-
-        ret = btrfs_qgroup_inherit(trans, fs_info,
-                                   root->root_key.objectid,
-                                   objectid, pending->inherit);
-        if (ret) {
-                btrfs_abort_transaction(trans, root, ret);
-                goto fail;
-        }
-
         /* see comments in should_cow_block() */
         set_bit(BTRFS_ROOT_FORCE_COW, &root->state);
         smp_wmb();
@@ -1502,11 +1489,37 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
                         goto fail;
                 }
         }
+
+        ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
+        if (ret) {
+                btrfs_abort_transaction(trans, root, ret);
+                goto fail;
+        }
+
+        /*
+         * account qgroup counters before qgroup_inherit()
+         */
+        ret = btrfs_qgroup_prepare_account_extents(trans, fs_info);
+        if (ret)
+                goto fail;
+        ret = btrfs_qgroup_account_extents(trans, fs_info);
+        if (ret)
+                goto fail;
+        ret = btrfs_qgroup_inherit(trans, fs_info,
+                                   root->root_key.objectid,
+                                   objectid, pending->inherit);
+        if (ret) {
+                btrfs_abort_transaction(trans, root, ret);
+                goto fail;
+        }
+
 fail:
         pending->error = ret;
 dir_item_existed:
         trans->block_rsv = rsv;
         trans->bytes_reserved = 0;
+clear_skip_qgroup:
+        btrfs_clear_skip_qgroup(trans);
 no_free_objectid:
         kfree(new_root_item);
 root_item_alloc_fail: