-
Notifications
You must be signed in to change notification settings - Fork 39.2k
/
rbd_util.go
441 lines (395 loc) · 13.4 KB
/
rbd_util.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
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
/*
Copyright 2014 The Kubernetes Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
//
// utility functions to setup rbd volume
// mainly implement diskManager interface
//
package rbd
import (
"encoding/json"
"errors"
"fmt"
"io/ioutil"
"math/rand"
"os"
"path"
"regexp"
"strings"
"time"
"github.com/golang/glog"
"k8s.io/kubernetes/pkg/api/v1"
"k8s.io/kubernetes/pkg/util/exec"
"k8s.io/kubernetes/pkg/util/mount"
"k8s.io/kubernetes/pkg/util/node"
"k8s.io/kubernetes/pkg/volume"
)
const (
imageWatcherStr = "watcher="
kubeLockMagic = "kubelet_lock_magic_"
)
// search /sys/bus for rbd device that matches given pool and image
func getDevFromImageAndPool(pool, image string) (string, bool) {
// /sys/bus/rbd/devices/X/name and /sys/bus/rbd/devices/X/pool
sys_path := "/sys/bus/rbd/devices"
if dirs, err := ioutil.ReadDir(sys_path); err == nil {
for _, f := range dirs {
// pool and name format:
// see rbd_pool_show() and rbd_name_show() at
// https://github.com/torvalds/linux/blob/master/drivers/block/rbd.c
name := f.Name()
// first match pool, then match name
po := path.Join(sys_path, name, "pool")
img := path.Join(sys_path, name, "name")
exe := exec.New()
out, err := exe.Command("cat", po, img).CombinedOutput()
if err != nil {
continue
}
matched, err := regexp.MatchString("^"+pool+"\n"+image+"\n$", string(out))
if err != nil || !matched {
continue
}
// found a match, check if device exists
devicePath := "/dev/rbd" + name
if _, err := os.Lstat(devicePath); err == nil {
return devicePath, true
}
}
}
return "", false
}
// stat a path, if not exists, retry maxRetries times
func waitForPath(pool, image string, maxRetries int) (string, bool) {
for i := 0; i < maxRetries; i++ {
devicePath, found := getDevFromImageAndPool(pool, image)
if found {
return devicePath, true
}
if i == maxRetries-1 {
break
}
time.Sleep(time.Second)
}
return "", false
}
// make a directory like /var/lib/kubelet/plugins/kubernetes.io/pod/rbd/pool-image-image
func makePDNameInternal(host volume.VolumeHost, pool string, image string) string {
return path.Join(host.GetPluginDir(rbdPluginName), "rbd", pool+"-image-"+image)
}
type RBDUtil struct{}
func (util *RBDUtil) MakeGlobalPDName(rbd rbd) string {
return makePDNameInternal(rbd.plugin.host, rbd.Pool, rbd.Image)
}
func (util *RBDUtil) rbdLock(b rbdMounter, lock bool) error {
var err error
var output, locker string
var cmd []byte
var secret_opt []string
if b.Secret != "" {
secret_opt = []string{"--key=" + b.Secret}
} else {
secret_opt = []string{"-k", b.Keyring}
}
if len(b.adminId) == 0 {
b.adminId = b.Id
}
if len(b.adminSecret) == 0 {
b.adminSecret = b.Secret
}
// construct lock id using host name and a magic prefix
lock_id := kubeLockMagic + node.GetHostname("")
l := len(b.Mon)
// avoid mount storm, pick a host randomly
start := rand.Int() % l
// iterate all hosts until mount succeeds.
for i := start; i < start+l; i++ {
mon := b.Mon[i%l]
// cmd "rbd lock list" serves two purposes:
// for fencing, check if lock already held for this host
// this edge case happens if host crashes in the middle of acquiring lock and mounting rbd
// for defencing, get the locker name, something like "client.1234"
cmd, err = b.plugin.execCommand("rbd",
append([]string{"lock", "list", b.Image, "--pool", b.Pool, "--id", b.Id, "-m", mon}, secret_opt...))
output = string(cmd)
glog.Infof("lock list output %q", output)
if err != nil {
continue
}
if lock {
// check if lock is already held for this host by matching lock_id and rbd lock id
if strings.Contains(output, lock_id) {
// this host already holds the lock, exit
glog.V(1).Infof("rbd: lock already held for %s", lock_id)
return nil
}
// clean up orphaned lock if no watcher on the image
used, statusErr := util.rbdStatus(&b)
if statusErr == nil && !used {
re := regexp.MustCompile("client.* " + kubeLockMagic + ".*")
locks := re.FindAllStringSubmatch(output, -1)
for _, v := range locks {
if len(v) > 0 {
lockInfo := strings.Split(v[0], " ")
if len(lockInfo) > 2 {
cmd, err = b.plugin.execCommand("rbd",
append([]string{"lock", "remove", b.Image, lockInfo[1], lockInfo[0], "--pool", b.Pool, "--id", b.Id, "-m", mon}, secret_opt...))
glog.Infof("remove orphaned locker %s from client %s: err %v, output: %s", lockInfo[1], lockInfo[0], err, string(cmd))
}
}
}
}
// hold a lock: rbd lock add
cmd, err = b.plugin.execCommand("rbd",
append([]string{"lock", "add", b.Image, lock_id, "--pool", b.Pool, "--id", b.Id, "-m", mon}, secret_opt...))
} else {
// defencing, find locker name
ind := strings.LastIndex(output, lock_id) - 1
for i := ind; i >= 0; i-- {
if output[i] == '\n' {
locker = output[(i + 1):ind]
break
}
}
// remove a lock: rbd lock remove
cmd, err = b.plugin.execCommand("rbd",
append([]string{"lock", "remove", b.Image, lock_id, locker, "--pool", b.Pool, "--id", b.Id, "-m", mon}, secret_opt...))
}
if err == nil {
//lock is acquired
break
}
}
return err
}
func (util *RBDUtil) persistRBD(rbd rbdMounter, mnt string) error {
file := path.Join(mnt, "rbd.json")
fp, err := os.Create(file)
if err != nil {
return fmt.Errorf("rbd: create err %s/%s", file, err)
}
defer fp.Close()
encoder := json.NewEncoder(fp)
if err = encoder.Encode(rbd); err != nil {
return fmt.Errorf("rbd: encode err: %v.", err)
}
return nil
}
func (util *RBDUtil) loadRBD(mounter *rbdMounter, mnt string) error {
file := path.Join(mnt, "rbd.json")
fp, err := os.Open(file)
if err != nil {
return fmt.Errorf("rbd: open err %s/%s", file, err)
}
defer fp.Close()
decoder := json.NewDecoder(fp)
if err = decoder.Decode(mounter); err != nil {
return fmt.Errorf("rbd: decode err: %v.", err)
}
return nil
}
func (util *RBDUtil) fencing(b rbdMounter) error {
// no need to fence readOnly
if (&b).GetAttributes().ReadOnly {
return nil
}
return util.rbdLock(b, true)
}
func (util *RBDUtil) defencing(c rbdUnmounter) error {
// no need to fence readOnly
if c.ReadOnly {
return nil
}
return util.rbdLock(*c.rbdMounter, false)
}
func (util *RBDUtil) AttachDisk(b rbdMounter) error {
var err error
var output []byte
// create mount point
globalPDPath := b.manager.MakeGlobalPDName(*b.rbd)
notMnt, err := b.mounter.IsLikelyNotMountPoint(globalPDPath)
// in the first time, the path shouldn't exist and IsLikelyNotMountPoint is expected to get NotExist
if err != nil && !os.IsNotExist(err) {
return fmt.Errorf("rbd: %s failed to check mountpoint", globalPDPath)
}
if !notMnt {
return nil
}
if err = os.MkdirAll(globalPDPath, 0750); err != nil {
return fmt.Errorf("rbd: failed to mkdir %s, error", globalPDPath)
}
devicePath, found := waitForPath(b.Pool, b.Image, 1)
if !found {
// modprobe
_, err = b.plugin.execCommand("modprobe", []string{"rbd"})
if err != nil {
return fmt.Errorf("rbd: failed to modprobe rbd error:%v", err)
}
// fence off other mappers
if err = util.fencing(b); err != nil {
return fmt.Errorf("rbd: image %s is locked by other nodes", b.Image)
}
// rbd lock remove needs ceph and image config
// but kubelet doesn't get them from apiserver during teardown
// so persit rbd config so upon disk detach, rbd lock can be removed
// since rbd json is persisted in the same local directory that is used as rbd mountpoint later,
// the json file remains invisible during rbd mount and thus won't be removed accidentally.
util.persistRBD(b, globalPDPath)
// rbd map
l := len(b.Mon)
// avoid mount storm, pick a host randomly
start := rand.Int() % l
// iterate all hosts until mount succeeds.
for i := start; i < start+l; i++ {
mon := b.Mon[i%l]
glog.V(1).Infof("rbd: map mon %s", mon)
if b.Secret != "" {
output, err = b.plugin.execCommand("rbd",
[]string{"map", b.Image, "--pool", b.Pool, "--id", b.Id, "-m", mon, "--key=" + b.Secret})
} else {
output, err = b.plugin.execCommand("rbd",
[]string{"map", b.Image, "--pool", b.Pool, "--id", b.Id, "-m", mon, "-k", b.Keyring})
}
if err == nil {
break
}
glog.V(1).Infof("rbd: map error %v %s", err, string(output))
}
if err != nil {
return fmt.Errorf("rbd: map failed %v %s", err, string(output))
}
devicePath, found = waitForPath(b.Pool, b.Image, 10)
if !found {
return errors.New("Could not map image: Timeout after 10s")
}
}
// mount it
if err = b.mounter.FormatAndMount(devicePath, globalPDPath, b.fsType, nil); err != nil {
err = fmt.Errorf("rbd: failed to mount rbd volume %s [%s] to %s, error %v", devicePath, b.fsType, globalPDPath, err)
}
return err
}
func (util *RBDUtil) DetachDisk(c rbdUnmounter, mntPath string) error {
device, cnt, err := mount.GetDeviceNameFromMount(c.mounter, mntPath)
if err != nil {
return fmt.Errorf("rbd detach disk: failed to get device from mnt: %s\nError: %v", mntPath, err)
}
if err = c.mounter.Unmount(mntPath); err != nil {
return fmt.Errorf("rbd detach disk: failed to umount: %s\nError: %v", mntPath, err)
}
// if device is no longer used, see if can unmap
if cnt <= 1 {
// rbd unmap
_, err = c.plugin.execCommand("rbd", []string{"unmap", device})
if err != nil {
return fmt.Errorf("rbd: failed to unmap device %s:Error: %v", device, err)
}
// load ceph and image/pool info to remove fencing
if err := util.loadRBD(c.rbdMounter, mntPath); err == nil {
// remove rbd lock
util.defencing(c)
}
glog.Infof("rbd: successfully unmap device %s", device)
}
return nil
}
func (util *RBDUtil) CreateImage(p *rbdVolumeProvisioner) (r *v1.RBDVolumeSource, size int, err error) {
var output []byte
capacity := p.options.PVC.Spec.Resources.Requests[v1.ResourceName(v1.ResourceStorage)]
volSizeBytes := capacity.Value()
// convert to MB that rbd defaults on
sz := int(volume.RoundUpSize(volSizeBytes, 1024*1024))
volSz := fmt.Sprintf("%d", sz)
// rbd create
l := len(p.rbdMounter.Mon)
// pick a mon randomly
start := rand.Int() % l
// iterate all monitors until create succeeds.
for i := start; i < start+l; i++ {
mon := p.Mon[i%l]
glog.V(4).Infof("rbd: create %s size %s using mon %s, pool %s id %s key %s", p.rbdMounter.Image, volSz, mon, p.rbdMounter.Pool, p.rbdMounter.adminId, p.rbdMounter.adminSecret)
output, err = p.rbdMounter.plugin.execCommand("rbd",
[]string{"create", p.rbdMounter.Image, "--size", volSz, "--pool", p.rbdMounter.Pool, "--id", p.rbdMounter.adminId, "-m", mon, "--key=" + p.rbdMounter.adminSecret, "--image-format", "1"})
if err == nil {
break
} else {
glog.Warningf("failed to create rbd image, output %v", string(output))
}
}
if err != nil {
return nil, 0, fmt.Errorf("failed to create rbd image: %v, command output: %s", err, string(output))
}
return &v1.RBDVolumeSource{
CephMonitors: p.rbdMounter.Mon,
RBDImage: p.rbdMounter.Image,
RBDPool: p.rbdMounter.Pool,
}, sz, nil
}
func (util *RBDUtil) DeleteImage(p *rbdVolumeDeleter) error {
var output []byte
found, err := util.rbdStatus(p.rbdMounter)
if err != nil {
return err
}
if found {
glog.Info("rbd is still being used ", p.rbdMounter.Image)
return fmt.Errorf("rbd %s is still being used", p.rbdMounter.Image)
}
// rbd rm
l := len(p.rbdMounter.Mon)
// pick a mon randomly
start := rand.Int() % l
// iterate all monitors until rm succeeds.
for i := start; i < start+l; i++ {
mon := p.rbdMounter.Mon[i%l]
glog.V(4).Infof("rbd: rm %s using mon %s, pool %s id %s key %s", p.rbdMounter.Image, mon, p.rbdMounter.Pool, p.rbdMounter.adminId, p.rbdMounter.adminSecret)
output, err = p.plugin.execCommand("rbd",
[]string{"rm", p.rbdMounter.Image, "--pool", p.rbdMounter.Pool, "--id", p.rbdMounter.adminId, "-m", mon, "--key=" + p.rbdMounter.adminSecret})
if err == nil {
return nil
} else {
glog.Errorf("failed to delete rbd image: %v, command output: %s", err, string(output))
}
}
return err
}
// run rbd status command to check if there is watcher on the image
func (util *RBDUtil) rbdStatus(b *rbdMounter) (bool, error) {
var err error
var output string
var cmd []byte
l := len(b.Mon)
start := rand.Int() % l
// iterate all hosts until mount succeeds.
for i := start; i < start+l; i++ {
mon := b.Mon[i%l]
// cmd "rbd status" list the rbd client watch with the following output:
// Watchers:
// watcher=10.16.153.105:0/710245699 client.14163 cookie=1
glog.V(4).Infof("rbd: status %s using mon %s, pool %s id %s key %s", b.Image, mon, b.Pool, b.adminId, b.adminSecret)
cmd, err = b.plugin.execCommand("rbd",
[]string{"status", b.Image, "--pool", b.Pool, "-m", mon, "--id", b.adminId, "--key=" + b.adminSecret})
output = string(cmd)
if err != nil {
// ignore error code, just checkout output for watcher string
glog.Warningf("failed to execute rbd status on mon %s", mon)
}
if strings.Contains(output, imageWatcherStr) {
glog.V(4).Infof("rbd: watchers on %s: %s", b.Image, output)
return true, nil
} else {
glog.Warningf("rbd: no watchers on %s", b.Image)
return false, nil
}
}
return false, nil
}