Clean-up made possible by btrfsutil.RebuiltForrest implementing btrfs.ReadableFS

 - rebuildtrees: Use .ForrestLookup instead of .RebuiltTree where possible

 - btrfsutil: noopRebuiltForrestCallbacks: Use only the generic
   btrfstree.Forrest API

 - btrfsutil: RebuiltForrest, RebuiltTree: Avoid unnecessarily
   reaching into forrest.inner

 - btrfsutil: RebuiltTree: Drop the .ReadItem() method; it duplicates
   .TreeLookup without benefit.

2 files changed, 9 insertions, 9 deletions

diff --git a/cmd/btrfs-rec/inspect/rebuildtrees/rebuild.go b/cmd/btrfs-rec/inspect/rebuildtrees/rebuild.go
index 7e2e49f..77d56ae 100644
--- a/cmd/btrfs-rec/inspect/rebuildtrees/rebuild.go
+++ b/cmd/btrfs-rec/inspect/rebuildtrees/rebuild.go
@@ -159,7 +159,7 @@ func (o *rebuilder) processTreeQueue(ctx context.Context) error {
 		}
 		// This will call o.AddedItem as nescessary, which
 		// inserts to o.addedItemQueue.
-		_, _ = o.rebuilt.RebuiltTree(ctx, o.curKey.TreeID)
+		_, _ = o.rebuilt.ForrestLookup(ctx, o.curKey.TreeID)
 	}
 
 	return nil
@@ -415,7 +415,7 @@ func (o *rebuilder) processSettledItemQueue(ctx context.Context) error {
 			ctx := dlog.WithField(ctx, "btrfs.inspect.rebuild-trees.rebuild.process.item", key)
 			item := keyAndBody{
 				itemToVisit: key,
-				Body:        discardErr(o.rebuilt.RebuiltTree(ctx, key.TreeID)).ReadItem(ctx, key.Key),
+				Body:        discardErr(discardErr(o.rebuilt.RebuiltTree(ctx, key.TreeID)).TreeLookup(ctx, key.Key)).Body,
 			}
 			if key.TreeID == btrfsprim.EXTENT_TREE_OBJECTID &&
 				(key.ItemType == btrfsprim.EXTENT_ITEM_KEY || key.ItemType == btrfsprim.METADATA_ITEM_KEY) {
diff --git a/cmd/btrfs-rec/inspect/rebuildtrees/rebuild_treecb.go b/cmd/btrfs-rec/inspect/rebuildtrees/rebuild_treecb.go
index e227cc7..15ad42c 100644
--- a/cmd/btrfs-rec/inspect/rebuildtrees/rebuild_treecb.go
+++ b/cmd/btrfs-rec/inspect/rebuildtrees/rebuild_treecb.go
@@ -36,7 +36,7 @@ func (o forrestCallbacks) AddedRoot(_ context.Context, tree btrfsprim.ObjID, _ b
 }
 
 // LookupRoot implements btrfsutil.RebuiltForrestCallbacks.
-func (o forrestCallbacks) LookupRoot(ctx context.Context, tree btrfsprim.ObjID) (offset btrfsprim.Generation, item btrfsitem.Root, ok bool) {
+func (o forrestCallbacks) LookupRoot(ctx context.Context, tree btrfsprim.ObjID) (offset btrfsprim.Generation, _item btrfsitem.Root, ok bool) {
 	wantKey := wantWithTree{
 		TreeID: btrfsprim.ROOT_TREE_OBJECTID,
 		Key: want{
@@ -51,9 +51,9 @@ func (o forrestCallbacks) LookupRoot(ctx context.Context, tree btrfsprim.ObjID)
 		o.enqueueRetry(btrfsprim.ROOT_TREE_OBJECTID)
 		return 0, btrfsitem.Root{}, false
 	}
-	itemBody := discardErr(o.rebuilt.RebuiltTree(ctx, wantKey.TreeID)).ReadItem(ctx, foundKey)
-	defer itemBody.Free()
-	switch itemBody := itemBody.(type) {
+	item, _ := discardErr(o.rebuilt.RebuiltTree(ctx, wantKey.TreeID)).TreeLookup(ctx, foundKey)
+	defer item.Body.Free()
+	switch itemBody := item.Body.(type) {
 	case *btrfsitem.Root:
 		return btrfsprim.Generation(foundKey.Offset), *itemBody, true
 	case *btrfsitem.Error:
@@ -77,9 +77,9 @@ func (o forrestCallbacks) LookupUUID(ctx context.Context, uuid btrfsprim.UUID) (
 		o.enqueueRetry(btrfsprim.UUID_TREE_OBJECTID)
 		return 0, false
 	}
-	itemBody := discardErr(o.rebuilt.RebuiltTree(ctx, wantKey.TreeID)).ReadItem(ctx, wantKey.Key.Key())
-	defer itemBody.Free()
-	switch itemBody := itemBody.(type) {
+	item, _ := discardErr(o.rebuilt.RebuiltTree(ctx, wantKey.TreeID)).TreeLookup(ctx, wantKey.Key.Key())
+	defer item.Body.Free()
+	switch itemBody := item.Body.(type) {
 	case *btrfsitem.UUIDMap:
 		return itemBody.ObjID, true
 	case *btrfsitem.Error: