summaryrefslogtreecommitdiff
path: root/cmd/btrfs-clear-bad-nodes/main.go
blob: 098d862982b25b8c88305cc28b8f61d633899ca0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
package main

import (
	"fmt"
	"os"

	"lukeshu.com/btrfs-tools/pkg/btrfs"
	"lukeshu.com/btrfs-tools/pkg/btrfs/btrfsitem"
	"lukeshu.com/btrfs-tools/pkg/btrfs/btrfsvol"
	"lukeshu.com/btrfs-tools/pkg/btrfsmisc"
	"lukeshu.com/btrfs-tools/pkg/util"
)

func main() {
	if err := Main(os.Args[1:]...); err != nil {
		fmt.Fprintf(os.Stderr, "%v: error: %v\n", os.Args[0], err)
		os.Exit(1)
	}
}

func Main(imgfilenames ...string) (err error) {
	maybeSetErr := func(_err error) {
		if _err != nil && err == nil {
			err = _err
		}
	}

	fs, err := btrfsmisc.Open(os.O_RDWR, imgfilenames...)
	if err != nil {
		return err
	}
	defer func() {
		maybeSetErr(fs.Close())
	}()

	var treeName string
	var treeID btrfs.ObjID
	btrfsmisc.WalkFS(fs, btrfsmisc.WalkFSHandler{
		PreTree: func(name string, id btrfs.ObjID, _ btrfsvol.LogicalAddr) {
			treeName = name
			treeID = id
		},
		Err: func(err error) {
			fmt.Printf("error: %v\n", err)
		},
		UnsafeNodes: true,
		TreeWalkHandler: btrfs.TreeWalkHandler{
			Node: func(path btrfs.TreePath, node *util.Ref[btrfsvol.LogicalAddr, btrfs.Node], err error) error {
				if node == nil || err == nil {
					return nil
				}
				origErr := err
				if len(path) < 2 {
					sb, err := fs.Superblock()
					if err != nil {
						return err
					}
					chunkRoot, err := fs.TreeLookup(sb.Data.RootTree, btrfs.Key{
						ObjectID: btrfs.CHUNK_TREE_OBJECTID,
						ItemType: btrfsitem.ROOT_ITEM_KEY,
						Offset:   0,
					})
					if err != nil {
						return err
					}
					chunkRootBody, ok := chunkRoot.Body.(btrfsitem.Root)
					if !ok {
						return fmt.Errorf("CHUNK_TREE_OBJECTID ROOT_ITEM has malformed body")
					}
					node.Data = btrfs.Node{
						Size:         node.Data.Size,
						ChecksumType: node.Data.ChecksumType,
						Head: btrfs.NodeHeader{
							//Checksum:   filled below,
							MetadataUUID:  sb.Data.EffectiveMetadataUUID(),
							Addr:          node.Addr,
							Flags:         btrfs.NodeWritten,
							BackrefRev:    btrfs.MixedBackrefRev,
							ChunkTreeUUID: chunkRootBody.UUID,
							Generation:    0,
							Owner:         treeID,
							NumItems:      0,
							Level:         0,
						},
					}
				} else {
					parentNode, err := fs.ReadNode(path[len(path)-2].NodeAddr)
					if err != nil {
						return err
					}
					node.Data = btrfs.Node{
						Size:         node.Data.Size,
						ChecksumType: node.Data.ChecksumType,
						Head: btrfs.NodeHeader{
							//Checksum:   filled below,
							MetadataUUID:  parentNode.Data.Head.MetadataUUID,
							Addr:          node.Addr,
							Flags:         btrfs.NodeWritten,
							BackrefRev:    parentNode.Data.Head.BackrefRev,
							ChunkTreeUUID: parentNode.Data.Head.ChunkTreeUUID,
							Generation:    0,
							Owner:         parentNode.Data.Head.Owner,
							NumItems:      0,
							Level:         parentNode.Data.Head.Level - 1,
						},
					}
				}
				node.Data.Head.Checksum, err = node.Data.CalculateChecksum()
				if err != nil {
					return btrfsmisc.WalkErr{
						TreeName: treeName,
						Path:     path,
						Err:      err,
					}
				}
				if err := node.Write(); err != nil {
					return err
				}

				fmt.Printf("fixed node@%v (err was %v)\n", node.Addr, origErr)
				return nil
			},
		},
	})

	return nil
}