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
|
// Copyright (C) 2022 Luke Shumaker <lukeshu@lukeshu.com>
//
// SPDX-License-Identifier: GPL-2.0-or-later
package main
import (
"bufio"
"fmt"
"os"
"strings"
"git.lukeshu.com/go/lowmemjson"
"github.com/datawire/dlib/dlog"
"github.com/datawire/ocibuild/pkg/cliutil"
"github.com/spf13/cobra"
"git.lukeshu.com/btrfs-progs-ng/lib/btrfs"
"git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfssum"
"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/maps"
)
func init() {
inspectors = append(inspectors, subcommand{
Command: cobra.Command{
Use: "dbgsums SCAN_RESULT.json",
Args: cliutil.WrapPositionalArgs(cobra.ExactArgs(1)),
},
RunE: func(fs *btrfs.FS, cmd *cobra.Command, args []string) (err error) {
maybeSetErr := func(_err error) {
if err == nil && _err != nil {
err = _err
}
}
ctx := cmd.Context()
dlog.Infof(ctx, "Reading %q...", args[0])
scanResults, err := func() (btrfsinspect.ScanDevicesResult, error) {
fh, err := os.Open(args[0])
if err != nil {
return nil, err
}
var scanResults btrfsinspect.ScanDevicesResult
if err := lowmemjson.DecodeThenEOF(fh, &scanResults); err != nil {
return nil, err
}
_ = fh.Close()
return scanResults, nil
}()
dlog.Infof(ctx, "... done reading %q", args[0])
dlog.Info(ctx, "Mapping the logical address space...")
type record struct {
Gen btrfs.Generation
Sum btrfssum.ShortSum
}
addrspace := make(map[btrfsvol.LogicalAddr]record)
var sumSize int
for _, devResults := range scanResults {
sumSize = devResults.Checksums.ChecksumSize
for _, sumItem := range devResults.FoundExtentCSums {
_ = sumItem.Sums.Walk(ctx, func(pos btrfsvol.LogicalAddr, sum btrfssum.ShortSum) error {
new := record{
Gen: sumItem.Generation,
Sum: sum,
}
if old, ok := addrspace[pos]; ok {
switch {
case old.Gen > new.Gen:
// do nothing
case old.Gen < new.Gen:
addrspace[pos] = new
case old.Gen == new.Gen:
if old != new {
dlog.Errorf(ctx, "mismatch of laddr=%v sum: %v != %v", pos, old, new)
}
}
} else {
addrspace[pos] = new
}
return nil
})
}
}
if len(addrspace) == 0 {
return fmt.Errorf("no checksums were found in the scan")
}
dlog.Info(ctx, "... done mapping")
dlog.Info(ctx, "Flattening the map ...")
var flattened btrfssum.SumRunWithGaps[btrfsvol.LogicalAddr]
var curAddr btrfsvol.LogicalAddr
var curSums strings.Builder
for _, laddr := range maps.SortedKeys(addrspace) {
if laddr != curAddr+(btrfsvol.LogicalAddr(curSums.Len()/sumSize)*btrfssum.BlockSize) {
if curSums.Len() > 0 {
flattened.Runs = append(flattened.Runs, btrfssum.SumRun[btrfsvol.LogicalAddr]{
ChecksumSize: sumSize,
Addr: curAddr,
Sums: btrfssum.ShortSum(curSums.String()),
})
}
curAddr = laddr
curSums.Reset()
}
curSums.WriteString(string(addrspace[laddr].Sum))
}
if curSums.Len() > 0 {
flattened.Runs = append(flattened.Runs, btrfssum.SumRun[btrfsvol.LogicalAddr]{
ChecksumSize: sumSize,
Addr: curAddr,
Sums: btrfssum.ShortSum(curSums.String()),
})
}
flattened.Addr = flattened.Runs[0].Addr
last := flattened.Runs[len(flattened.Runs)-1]
end := last.Addr.Add(last.Size())
flattened.Size = end.Sub(flattened.Addr)
dlog.Info(ctx, "... done flattening")
dlog.Info(ctx, "Writing addrspace sums to stdout...")
buffer := bufio.NewWriter(os.Stdout)
defer func() {
maybeSetErr(buffer.Flush())
}()
return lowmemjson.Encode(&lowmemjson.ReEncoder{
Out: buffer,
Indent: "\t",
ForceTrailingNewlines: true,
}, flattened)
},
})
}
|
