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
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
|
// Copyright (C) 2022 Luke Shumaker <lukeshu@lukeshu.com>
//
// SPDX-License-Identifier: GPL-2.0-or-later
package rebuildnodes
import (
"context"
"errors"
"fmt"
iofs "io/fs"
"reflect"
"strings"
"github.com/datawire/dlib/dlog"
"git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfsprim"
"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/containers"
"git.lukeshu.com/btrfs-progs-ng/lib/diskio"
"git.lukeshu.com/btrfs-progs-ng/lib/maps"
)
// classifyNodes returns
//
// 1. the set of nodes don't have another node claiming it as a child, and
// 2. the set of bad-nodes, with reconstructed headers filled in.
func classifyNodes(ctx context.Context, fs _FS, scanResults btrfsinspect.ScanDevicesResult) (
orphanedNodes map[btrfsvol.LogicalAddr]struct{},
rebuiltNodes map[btrfsvol.LogicalAddr]*RebuiltNode,
err error,
) {
dlog.Info(ctx, "Walking trees to identify orphan and broken nodes...")
sb, err := fs.Superblock()
if err != nil {
return nil, nil, err
}
chunkTreeUUID, ok := getChunkTreeUUID(ctx, fs)
if !ok {
return nil, nil, fmt.Errorf("could not look up chunk tree UUID")
}
lastPct := -1
total := countNodes(scanResults)
visitedNodes := make(map[btrfsvol.LogicalAddr]struct{})
progress := func() {
done := len(visitedNodes)
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)
walkHandler := btrfstree.TreeWalkHandler{
PreNode: func(path btrfstree.TreePath) 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
}
return nil
},
Node: func(path btrfstree.TreePath, _ *diskio.Ref[btrfsvol.LogicalAddr, btrfstree.Node]) error {
addr := path.Node(-1).ToNodeAddr
visitedNodes[addr] = struct{}{}
progress()
return nil
},
BadNode: func(path btrfstree.TreePath, _ *diskio.Ref[btrfsvol.LogicalAddr, btrfstree.Node], err error) error {
node := btrfstree.Node{
Size: sb.NodeSize,
ChecksumType: sb.ChecksumType,
Head: btrfstree.NodeHeader{
MetadataUUID: sb.EffectiveMetadataUUID(),
Addr: path.Node(-1).ToNodeAddr,
ChunkTreeUUID: chunkTreeUUID,
//Owner: TBD, // see RebuiltNode.InTrees
Generation: path.Node(-1).FromGeneration,
Level: path.Node(-1).ToNodeLevel,
},
}
min, max := spanOfTreePath(fs, path)
if other, ok := rebuiltNodes[path.Node(-1).ToNodeAddr]; ok {
if !reflect.DeepEqual(other.Node, node) {
dlog.Errorf(ctx, "... mismatch: %v != %v", node, other.Node)
return err
}
if min.Cmp(other.MinKey) > 0 { // if min > other.MinKey {
other.MinKey = min // take the max of the two
}
if max.Cmp(other.MaxKey) < 0 { // if max < other.MaxKey {
other.MaxKey = max // take the min of the two
}
other.InTrees.Insert(path.Node(-1).FromTree)
} else {
rebuiltNodes[path.Node(-1).ToNodeAddr] = &RebuiltNode{
Err: err.Error(),
MinKey: min,
MaxKey: max,
InTrees: containers.Set[btrfsprim.ObjID]{path.Node(-1).FromTree: struct{}{}},
Node: node,
}
}
return err
},
}
btrfsutil.WalkAllTrees(ctx, fs, btrfsutil.WalkAllTreesHandler{
TreeWalkHandler: walkHandler,
Err: func(err *btrfsutil.WalkError) {
// do nothing
if !errors.Is(err, btrfstree.ErrNotANode) && !strings.Contains(err.Error(), "read: could not map logical address") {
dlog.Errorf(ctx, "dbg walk err: %v", err)
}
},
})
// Start with 'orphanedRoots' as a complete set of all orphaned nodes, and then delete
// non-root entries from it.
orphanedNodes = make(map[btrfsvol.LogicalAddr]struct{})
for _, devResults := range scanResults {
for laddr := range devResults.FoundNodes {
if _, attached := visitedNodes[laddr]; !attached {
orphanedNodes[laddr] = struct{}{}
}
}
}
if len(visitedNodes)+len(orphanedNodes) != total {
panic("should not happen")
}
dlog.Infof(ctx,
"... (finished processing %v attached nodes, proceeding to process %v lost nodes, for a total of %v)",
len(visitedNodes), len(orphanedNodes), len(visitedNodes)+len(orphanedNodes))
for _, potentialRoot := range maps.SortedKeys(orphanedNodes) {
walkHandler.Node = func(path btrfstree.TreePath, _ *diskio.Ref[btrfsvol.LogicalAddr, btrfstree.Node]) error {
addr := path.Node(-1).ToNodeAddr
if addr != potentialRoot {
delete(orphanedNodes, addr)
}
visitedNodes[addr] = struct{}{}
progress()
return nil
}
walkFromNode(ctx, fs, potentialRoot,
func(err *btrfstree.TreeError) {
// do nothing
},
walkHandler,
)
}
if len(visitedNodes) != total {
panic("should not happen")
}
dlog.Infof(ctx, "... identified %d orphaned nodes and re-built %d nodes", len(orphanedNodes), len(rebuiltNodes))
return orphanedNodes, rebuiltNodes, nil
}
|
