1 files changed, 101 insertions, 0 deletions
diff --git a/lib/btrfsprogs/btrfsinspect/rebuildnodes/s3_reinit.go b/lib/btrfsprogs/btrfsinspect/rebuildnodes/s3_reinit.go
new file mode 100644
index 0000000..343956c
--- /dev/null
+++ b/lib/btrfsprogs/btrfsinspect/rebuildnodes/s3_reinit.go
@@ -0,0 +1,101 @@
+// Copyright (C) 2022  Luke Shumaker <lukeshu@lukeshu.com>
+//
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+package rebuildnodes
+
+import (
+	"context"
+	"fmt"
+	iofs "io/fs"
+
+	"github.com/datawire/dlib/dlog"
+
+	"git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfstree"
+	"git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfsvol"
+	"git.lukeshu.com/btrfs-progs-ng/lib/btrfsprogs/btrfsinspect"
+	"git.lukeshu.com/btrfs-progs-ng/lib/btrfsprogs/btrfsutil"
+	"git.lukeshu.com/btrfs-progs-ng/lib/diskio"
+)
+
+func reInitBrokenNodes(ctx context.Context, fs _FS, nodeScanResults btrfsinspect.ScanDevicesResult, foundRoots map[btrfsvol.LogicalAddr]struct{}) (map[btrfsvol.LogicalAddr]*RebuiltNode, error) {
+	sb, err := fs.Superblock()
+	if err != nil {
+		return nil, err
+	}
+
+	chunkTreeUUID, ok := getChunkTreeUUID(ctx, fs)
+	if !ok {
+		return nil, fmt.Errorf("could not look up chunk tree UUID")
+	}
+
+	lastPct := -1
+	total := countNodes(nodeScanResults)
+	done := 0
+	progress := func() {
+		pct := int(100 * float64(done) / float64(total))
+		if pct != lastPct || done == total {
+			dlog.Infof(ctx, "... %v%% (%v/%v)",
+				pct, done, total)
+			lastPct = pct
+		}
+	}
+
+	rebuiltNodes := make(map[btrfsvol.LogicalAddr]*RebuiltNode)
+	visitedNodes := make(map[btrfsvol.LogicalAddr]struct{})
+	walkHandler := btrfstree.TreeWalkHandler{
+		Node: func(path btrfstree.TreePath, _ *diskio.Ref[btrfsvol.LogicalAddr, btrfstree.Node]) error {
+			addr := path.Node(-1).ToNodeAddr
+			if _, alreadyVisited := visitedNodes[addr]; alreadyVisited {
+				// Can happen because of COW subvolumes;
+				// this is really a DAG not a tree.
+				return iofs.SkipDir
+			}
+			visitedNodes[addr] = struct{}{}
+			done++
+			progress()
+			return nil
+		},
+		BadNode: func(path btrfstree.TreePath, node *diskio.Ref[btrfsvol.LogicalAddr, btrfstree.Node], err error) error {
+			min, max := spanOfTreePath(fs, path)
+			rebuiltNodes[path.Node(-1).ToNodeAddr] = &RebuiltNode{
+				Err:    err,
+				MinKey: min,
+				MaxKey: max,
+				Node: btrfstree.Node{
+					Head: btrfstree.NodeHeader{
+						MetadataUUID:  sb.EffectiveMetadataUUID(),
+						Addr:          path.Node(-1).ToNodeAddr,
+						ChunkTreeUUID: chunkTreeUUID,
+						Owner:         path.Node(-1).FromTree,
+						Generation:    path.Node(-1).FromGeneration,
+						Level:         path.Node(-1).ToNodeLevel,
+					},
+				},
+			}
+			return err
+		},
+	}
+
+	// We use WalkAllTrees instead of just iterating over
+	// nodeScanResults so that we don't need to specifically check
+	// if any of the root nodes referenced directly by the
+	// superblock are dead.
+	progress()
+	btrfsutil.WalkAllTrees(ctx, fs, btrfsutil.WalkAllTreesHandler{
+		Err: func(err *btrfsutil.WalkError) {
+			// do nothing
+		},
+		TreeWalkHandler: walkHandler,
+	})
+	for foundRoot := range foundRoots {
+		walkFromNode(ctx, fs, foundRoot,
+			func(err *btrfstree.TreeError) {
+				// do nothing
+			},
+			walkHandler)
+	}
+	progress()
+
+	return rebuiltNodes, nil
+}