From e3f0e61282d0190b9744c69ce69dcaeea22e6a3e Mon Sep 17 00:00:00 2001
From: Luke Shumaker <lukeshu@lukeshu.com>
Date: Thu, 30 Mar 2023 15:11:31 -0600
Subject: btrfs: ReadableFS: Also embed btrfstree.NodeSource

---
 lib/btrfs/io3_btree.go               |  8 +++++---
 lib/btrfsutil/old_rebuilt_forrest.go | 10 ++++++++++
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/lib/btrfs/io3_btree.go b/lib/btrfs/io3_btree.go
index 01797df..50736cf 100644
--- a/lib/btrfs/io3_btree.go
+++ b/lib/btrfs/io3_btree.go
@@ -92,11 +92,13 @@ var _ btrfstree.Forrest = (*FS)(nil)
 // ReadableFS //////////////////////////////////////////////////////////////////
 
 type ReadableFS interface {
-	btrfstree.Forrest
+	Name() string
 
-	Superblock() (*btrfstree.Superblock, error)
+	// For reading btrees.
+	btrfstree.Forrest
 
-	Name() string
+	// For reading the superblock and raw nodes.
+	btrfstree.NodeSource
 
 	// For reading file contents.
 	diskio.ReaderAt[btrfsvol.LogicalAddr]
diff --git a/lib/btrfsutil/old_rebuilt_forrest.go b/lib/btrfsutil/old_rebuilt_forrest.go
index 91fa275..535aa94 100644
--- a/lib/btrfsutil/old_rebuilt_forrest.go
+++ b/lib/btrfsutil/old_rebuilt_forrest.go
@@ -461,6 +461,16 @@ func (bt *OldRebuiltForrest) Superblock() (*btrfstree.Superblock, error) {
 	return bt.inner.Superblock()
 }
 
+// AcquireNode implements btrfstree.NodeSource (and btrfs.ReadableFS).
+func (bt *OldRebuiltForrest) AcquireNode(ctx context.Context, addr btrfsvol.LogicalAddr, exp btrfstree.NodeExpectations) (*btrfstree.Node, error) {
+	return bt.inner.AcquireNode(ctx, addr, exp)
+}
+
+// ReleaseNode implements btrfstree.NodeSource (and btrfs.ReadableFS).
+func (bt *OldRebuiltForrest) ReleaseNode(node *btrfstree.Node) {
+	bt.inner.ReleaseNode(node)
+}
+
 // ReadAt implements diskio.ReaderAt[btrfsvol.LogicalAddr] (and btrfs.ReadableFS).
 func (bt *OldRebuiltForrest) ReadAt(p []byte, off btrfsvol.LogicalAddr) (int, error) {
 	return bt.inner.ReadAt(p, off)
-- 
cgit v1.1-4-g5e80