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
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
|
// Copyright (C) 2022 Luke Shumaker <lukeshu@lukeshu.com>
//
// SPDX-License-Identifier: GPL-2.0-or-later
package rebuildnodes
import (
"context"
"fmt"
"github.com/datawire/dlib/dlog"
"git.lukeshu.com/btrfs-progs-ng/lib/btrfs"
"git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfsitem"
"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/containers"
"git.lukeshu.com/btrfs-progs-ng/lib/maps"
)
type nodeData struct {
Level uint8
Generation btrfsprim.Generation
Owner btrfsprim.ObjID
NumItems uint32
MinItem btrfsprim.Key
MaxItem btrfsprim.Key
}
type kpData struct {
FromTree btrfsprim.ObjID
FromNode btrfsvol.LogicalAddr
FromItem int
ToNode btrfsvol.LogicalAddr
ToLevel uint8
ToKey btrfsprim.Key
ToGeneration btrfsprim.Generation
}
func (kp kpData) String() string {
return fmt.Sprintf(`{t:%v,n:%v}[%d]->{n:%v,l:%v,g:%v,k:(%d,%v,%d)}`,
kp.FromTree, kp.FromNode, kp.FromItem,
kp.ToNode, kp.ToLevel, kp.ToGeneration,
kp.ToKey.ObjectID,
kp.ToKey.ItemType,
kp.ToKey.Offset)
}
type nodeGraph struct {
Nodes map[btrfsvol.LogicalAddr]nodeData
BadNodes map[btrfsvol.LogicalAddr]error
EdgesFrom map[btrfsvol.LogicalAddr][]*kpData
EdgesTo map[btrfsvol.LogicalAddr][]*kpData
}
func (g nodeGraph) insertEdge(kp kpData) {
ptr := &kp
g.EdgesFrom[kp.FromNode] = append(g.EdgesFrom[kp.FromNode], ptr)
g.EdgesTo[kp.ToNode] = append(g.EdgesTo[kp.ToNode], ptr)
}
func (g nodeGraph) insertTreeRoot(sb btrfstree.Superblock, treeID btrfsprim.ObjID) {
treeInfo, _ := btrfstree.LookupTreeRoot(nil, sb, treeID)
g.insertEdge(kpData{
FromTree: treeID,
ToNode: treeInfo.RootNode,
ToLevel: treeInfo.Level,
ToGeneration: treeInfo.Generation,
})
}
type scanResult struct {
uuidMap
nodeGraph
}
func ScanDevices(ctx context.Context, fs *btrfs.FS, scanResults btrfsinspect.ScanDevicesResult) (*scanResult, error) {
dlog.Infof(ctx, "Reading node data from FS...")
sb, err := fs.Superblock()
if err != nil {
return nil, err
}
lastPct := -1
total := countNodes(scanResults)
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
}
}
ret := &scanResult{
uuidMap: uuidMap{
ObjID2UUID: make(map[btrfsprim.ObjID]btrfsprim.UUID),
UUID2ObjID: make(map[btrfsprim.UUID]btrfsprim.ObjID),
TreeParent: make(map[btrfsprim.ObjID]btrfsprim.UUID),
SeenTrees: make(containers.Set[btrfsprim.ObjID]),
},
nodeGraph: nodeGraph{
Nodes: make(map[btrfsvol.LogicalAddr]nodeData),
BadNodes: make(map[btrfsvol.LogicalAddr]error),
EdgesFrom: make(map[btrfsvol.LogicalAddr][]*kpData),
EdgesTo: make(map[btrfsvol.LogicalAddr][]*kpData),
},
}
// These 4 trees are mentioned directly in the superblock, so
// they are always seen.
//
// 1
ret.SeenTrees.Insert(btrfsprim.ROOT_TREE_OBJECTID)
ret.insertTreeRoot(*sb, btrfsprim.ROOT_TREE_OBJECTID)
// 2
ret.SeenTrees.Insert(btrfsprim.CHUNK_TREE_OBJECTID)
ret.insertTreeRoot(*sb, btrfsprim.CHUNK_TREE_OBJECTID)
// 3
ret.SeenTrees.Insert(btrfsprim.TREE_LOG_OBJECTID)
ret.insertTreeRoot(*sb, btrfsprim.TREE_LOG_OBJECTID)
// 4
ret.SeenTrees.Insert(btrfsprim.BLOCK_GROUP_TREE_OBJECTID)
ret.insertTreeRoot(*sb, btrfsprim.BLOCK_GROUP_TREE_OBJECTID)
progress()
for _, devResults := range scanResults {
for laddr := range devResults.FoundNodes {
nodeRef, err := btrfstree.ReadNode[btrfsvol.LogicalAddr](fs, *sb, laddr, btrfstree.NodeExpectations{
LAddr: containers.Optional[btrfsvol.LogicalAddr]{OK: true, Val: laddr},
})
if err != nil {
return nil, err
}
// UUID map rebuilding
for _, item := range nodeRef.Data.BodyLeaf {
switch itemBody := item.Body.(type) {
case btrfsitem.Root:
if err := maybeSet("ObjID2UUID", ret.ObjID2UUID, item.Key.ObjectID, itemBody.UUID); err != nil {
return nil, err
}
if itemBody.UUID != (btrfsprim.UUID{}) {
if err := maybeSet("UUID2ObjID", ret.UUID2ObjID, itemBody.UUID, item.Key.ObjectID); err != nil {
return nil, err
}
}
if err := maybeSet("ParentUUID", ret.TreeParent, item.Key.ObjectID, itemBody.ParentUUID); err != nil {
return nil, err
}
ret.SeenTrees.Insert(item.Key.ObjectID)
// graph building
ret.insertEdge(kpData{
FromTree: item.Key.ObjectID,
ToNode: itemBody.ByteNr,
ToLevel: itemBody.Level,
ToGeneration: itemBody.Generation,
})
case btrfsitem.UUIDMap:
uuid := btrfsitem.KeyToUUID(item.Key)
if err := maybeSet("ObjID2UUID", ret.ObjID2UUID, itemBody.ObjID, uuid); err != nil {
return nil, err
}
if err := maybeSet("UUID2ObjID", ret.UUID2ObjID, uuid, itemBody.ObjID); err != nil {
return nil, err
}
}
}
ret.SeenTrees.Insert(nodeRef.Data.Head.Owner)
// graph building
ret.Nodes[laddr] = nodeData{
Level: nodeRef.Data.Head.Level,
Generation: nodeRef.Data.Head.Generation,
Owner: nodeRef.Data.Head.Owner,
NumItems: nodeRef.Data.Head.NumItems,
MinItem: func() btrfsprim.Key { k, _ := nodeRef.Data.MinItem(); return k }(),
MaxItem: func() btrfsprim.Key { k, _ := nodeRef.Data.MaxItem(); return k }(),
}
for i, kp := range nodeRef.Data.BodyInternal {
ret.insertEdge(kpData{
FromTree: nodeRef.Data.Head.Owner,
FromNode: laddr,
FromItem: i,
ToNode: kp.BlockPtr,
ToLevel: nodeRef.Data.Head.Level - 1,
ToKey: kp.Key,
ToGeneration: kp.Generation,
})
}
done++
progress()
}
}
if done != total {
panic("should not happen")
}
missing := ret.missingRootItems()
if len(missing) > 0 {
dlog.Errorf(ctx, "... could not find root items for %d trees: %v", len(missing), maps.SortedKeys(missing))
}
dlog.Info(ctx, "... done reading node data")
dlog.Infof(ctx, "Checking keypointers for dead-ends...")
total = len(ret.EdgesTo)
done = 0
progress()
for laddr := range ret.EdgesTo {
if _, ok := ret.Nodes[laddr]; !ok {
_, err := btrfstree.ReadNode[btrfsvol.LogicalAddr](fs, *sb, laddr, btrfstree.NodeExpectations{
LAddr: containers.Optional[btrfsvol.LogicalAddr]{OK: true, Val: laddr},
})
if err == nil {
return nil, fmt.Errorf("node@%v exists but was not in node scan results", laddr)
}
ret.BadNodes[laddr] = err
}
done++
progress()
}
dlog.Info(ctx, "... done checking keypointers")
return ret, nil
}
|