-
Notifications
You must be signed in to change notification settings - Fork 18.6k
/
volumes.go
297 lines (255 loc) · 6.61 KB
/
volumes.go
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
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
package daemon
import (
"encoding/json"
"fmt"
"io/ioutil"
"os"
"path/filepath"
"strings"
"github.com/docker/docker/pkg/chrootarchive"
"github.com/docker/docker/runconfig"
"github.com/docker/docker/volume"
"github.com/docker/libcontainer/label"
)
type mountPoint struct {
Name string
Destination string
Driver string
RW bool
Volume volume.Volume `json:"-"`
Source string
Relabel string
}
func (m *mountPoint) Setup() (string, error) {
if m.Volume != nil {
return m.Volume.Mount()
}
if len(m.Source) > 0 {
if _, err := os.Stat(m.Source); err != nil {
if !os.IsNotExist(err) {
return "", err
}
if err := os.MkdirAll(m.Source, 0755); err != nil {
return "", err
}
}
return m.Source, nil
}
return "", fmt.Errorf("Unable to setup mount point, neither source nor volume defined")
}
func (m *mountPoint) Path() string {
if m.Volume != nil {
return m.Volume.Path()
}
return m.Source
}
func parseBindMount(spec string, mountLabel string, config *runconfig.Config) (*mountPoint, error) {
bind := &mountPoint{
RW: true,
}
arr := strings.Split(spec, ":")
switch len(arr) {
case 2:
bind.Destination = arr[1]
case 3:
bind.Destination = arr[1]
mode := arr[2]
if !validMountMode(mode) {
return nil, fmt.Errorf("invalid mode for volumes-from: %s", mode)
}
bind.RW = rwModes[mode]
// Relabel will apply a SELinux label, if necessary
bind.Relabel = mode
default:
return nil, fmt.Errorf("Invalid volume specification: %s", spec)
}
name, source, err := parseVolumeSource(arr[0], config)
if err != nil {
return nil, err
}
if len(source) == 0 {
bind.Driver = config.VolumeDriver
if len(bind.Driver) == 0 {
bind.Driver = volume.DefaultDriverName
}
} else {
bind.Source = filepath.Clean(source)
}
bind.Name = name
bind.Destination = filepath.Clean(bind.Destination)
return bind, nil
}
func parseVolumesFrom(spec string) (string, string, error) {
if len(spec) == 0 {
return "", "", fmt.Errorf("malformed volumes-from specification: %s", spec)
}
specParts := strings.SplitN(spec, ":", 2)
id := specParts[0]
mode := "rw"
if len(specParts) == 2 {
mode = specParts[1]
if !validMountMode(mode) {
return "", "", fmt.Errorf("invalid mode for volumes-from: %s", mode)
}
}
return id, mode, nil
}
// read-write modes
var rwModes = map[string]bool{
"rw": true,
"rw,Z": true,
"rw,z": true,
"z,rw": true,
"Z,rw": true,
"Z": true,
"z": true,
}
// read-only modes
var roModes = map[string]bool{
"ro": true,
"ro,Z": true,
"ro,z": true,
"z,ro": true,
"Z,ro": true,
}
func validMountMode(mode string) bool {
return roModes[mode] || rwModes[mode]
}
func copyExistingContents(source, destination string) error {
volList, err := ioutil.ReadDir(source)
if err != nil {
return err
}
if len(volList) > 0 {
srcList, err := ioutil.ReadDir(destination)
if err != nil {
return err
}
if len(srcList) == 0 {
// If the source volume is empty copy files from the root into the volume
if err := chrootarchive.CopyWithTar(source, destination); err != nil {
return err
}
}
}
return copyOwnership(source, destination)
}
// registerMountPoints initializes the container mount points with the configured volumes and bind mounts.
// It follows the next sequence to decide what to mount in each final destination:
//
// 1. Select the previously configured mount points for the containers, if any.
// 2. Select the volumes mounted from another containers. Overrides previously configured mount point destination.
// 3. Select the bind mounts set by the client. Overrides previously configured mount point destinations.
func (daemon *Daemon) registerMountPoints(container *Container, hostConfig *runconfig.HostConfig) error {
binds := map[string]bool{}
mountPoints := map[string]*mountPoint{}
// 1. Read already configured mount points.
for name, point := range container.MountPoints {
mountPoints[name] = point
}
// 2. Read volumes from other containers.
for _, v := range hostConfig.VolumesFrom {
containerID, mode, err := parseVolumesFrom(v)
if err != nil {
return err
}
c, err := daemon.Get(containerID)
if err != nil {
return err
}
for _, m := range c.MountPoints {
cp := m
cp.RW = m.RW && mode != "ro"
if len(m.Source) == 0 {
v, err := createVolume(m.Name, m.Driver)
if err != nil {
return err
}
cp.Volume = v
}
mountPoints[cp.Destination] = cp
}
}
// 3. Read bind mounts
for _, b := range hostConfig.Binds {
// #10618
bind, err := parseBindMount(b, container.MountLabel, container.Config)
if err != nil {
return err
}
if binds[bind.Destination] {
return fmt.Errorf("Duplicate bind mount %s", bind.Destination)
}
if len(bind.Name) > 0 && len(bind.Driver) > 0 {
// create the volume
v, err := createVolume(bind.Name, bind.Driver)
if err != nil {
return err
}
bind.Volume = v
bind.Source = v.Path()
// Since this is just a named volume and not a typical bind, set to shared mode `z`
if bind.Relabel == "" {
bind.Relabel = "z"
}
}
if err := label.Relabel(bind.Source, container.MountLabel, bind.Relabel); err != nil {
return err
}
binds[bind.Destination] = true
mountPoints[bind.Destination] = bind
}
container.Lock()
container.MountPoints = mountPoints
container.Unlock()
return nil
}
// verifyOldVolumesInfo ports volumes configured for the containers pre docker 1.7.
// It reads the container configuration and creates valid mount points for the old volumes.
func (daemon *Daemon) verifyOldVolumesInfo(container *Container) error {
jsonPath, err := container.jsonPath()
if err != nil {
return err
}
f, err := os.Open(jsonPath)
if err != nil {
if os.IsNotExist(err) {
return nil
}
return err
}
type oldContVolCfg struct {
Volumes map[string]string
VolumesRW map[string]bool
}
vols := oldContVolCfg{
Volumes: make(map[string]string),
VolumesRW: make(map[string]bool),
}
if err := json.NewDecoder(f).Decode(&vols); err != nil {
return err
}
for destination, hostPath := range vols.Volumes {
vfsPath := filepath.Join(daemon.root, "vfs", "dir")
if strings.HasPrefix(hostPath, vfsPath) {
id := filepath.Base(hostPath)
rw := vols.VolumesRW != nil && vols.VolumesRW[destination]
container.addLocalMountPoint(id, destination, rw)
}
}
return container.ToDisk()
}
func createVolume(name, driverName string) (volume.Volume, error) {
vd, err := getVolumeDriver(driverName)
if err != nil {
return nil, err
}
return vd.Create(name)
}
func removeVolume(v volume.Volume) error {
vd, err := getVolumeDriver(v.DriverName())
if err != nil {
return nil
}
return vd.Remove(v)
}