forked from hashicorp/nomad
-
Notifications
You must be signed in to change notification settings - Fork 1
/
qemu.go
398 lines (352 loc) · 11.1 KB
/
qemu.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
package driver
import (
"encoding/json"
"fmt"
"log"
"os/exec"
"path/filepath"
"regexp"
"runtime"
"strings"
"time"
"github.com/hashicorp/go-plugin"
"github.com/hashicorp/nomad/client/allocdir"
"github.com/hashicorp/nomad/client/config"
"github.com/hashicorp/nomad/client/driver/executor"
cstructs "github.com/hashicorp/nomad/client/driver/structs"
"github.com/hashicorp/nomad/client/fingerprint"
"github.com/hashicorp/nomad/helper/discover"
"github.com/hashicorp/nomad/helper/fields"
"github.com/hashicorp/nomad/nomad/structs"
"github.com/mitchellh/mapstructure"
)
var (
reQemuVersion = regexp.MustCompile(`version (\d[\.\d+]+)`)
)
const (
// The key populated in Node Attributes to indicate presence of the Qemu
// driver
qemuDriverAttr = "driver.qemu"
)
// QemuDriver is a driver for running images via Qemu
// We attempt to chose sane defaults for now, with more configuration available
// planned in the future
type QemuDriver struct {
DriverContext
fingerprint.StaticFingerprinter
}
type QemuDriverConfig struct {
ImagePath string `mapstructure:"image_path"`
Accelerator string `mapstructure:"accelerator"`
PortMap []map[string]int `mapstructure:"port_map"` // A map of host port labels and to guest ports.
}
// qemuHandle is returned from Start/Open as a handle to the PID
type qemuHandle struct {
pluginClient *plugin.Client
userPid int
executor executor.Executor
allocDir *allocdir.AllocDir
killTimeout time.Duration
maxKillTimeout time.Duration
logger *log.Logger
version string
waitCh chan *cstructs.WaitResult
doneCh chan struct{}
}
// NewQemuDriver is used to create a new exec driver
func NewQemuDriver(ctx *DriverContext) Driver {
return &QemuDriver{DriverContext: *ctx}
}
// Validate is used to validate the driver configuration
func (d *QemuDriver) Validate(config map[string]interface{}) error {
fd := &fields.FieldData{
Raw: config,
Schema: map[string]*fields.FieldSchema{
"image_path": &fields.FieldSchema{
Type: fields.TypeString,
Required: true,
},
"accelerator": &fields.FieldSchema{
Type: fields.TypeString,
},
"port_map": &fields.FieldSchema{
Type: fields.TypeArray,
},
},
}
if err := fd.Validate(); err != nil {
return err
}
return nil
}
func (d *QemuDriver) Fingerprint(cfg *config.Config, node *structs.Node) (bool, error) {
// Get the current status so that we can log any debug messages only if the
// state changes
_, currentlyEnabled := node.Attributes[qemuDriverAttr]
bin := "qemu-system-x86_64"
if runtime.GOOS == "windows" {
// On windows, the "qemu-system-x86_64" command does not respond to the
// version flag.
bin = "qemu-img"
}
outBytes, err := exec.Command(bin, "--version").Output()
if err != nil {
delete(node.Attributes, qemuDriverAttr)
return false, nil
}
out := strings.TrimSpace(string(outBytes))
matches := reQemuVersion.FindStringSubmatch(out)
if len(matches) != 2 {
delete(node.Attributes, qemuDriverAttr)
return false, fmt.Errorf("Unable to parse Qemu version string: %#v", matches)
}
if !currentlyEnabled {
d.logger.Printf("[DEBUG] driver.qemu: enabling driver")
}
node.Attributes[qemuDriverAttr] = "1"
node.Attributes["driver.qemu.version"] = matches[1]
return true, nil
}
// Run an existing Qemu image. Start() will pull down an existing, valid Qemu
// image and save it to the Drivers Allocation Dir
func (d *QemuDriver) Start(ctx *ExecContext, task *structs.Task) (DriverHandle, error) {
var driverConfig QemuDriverConfig
if err := mapstructure.WeakDecode(task.Config, &driverConfig); err != nil {
return nil, err
}
if len(driverConfig.PortMap) > 1 {
return nil, fmt.Errorf("Only one port_map block is allowed in the qemu driver config")
}
// Get the image source
vmPath := driverConfig.ImagePath
if vmPath == "" {
return nil, fmt.Errorf("image_path must be set")
}
vmID := filepath.Base(vmPath)
// Get the tasks local directory.
taskDir, ok := ctx.AllocDir.TaskDirs[d.DriverContext.taskName]
if !ok {
return nil, fmt.Errorf("Could not find task directory for task: %v", d.DriverContext.taskName)
}
// Parse configuration arguments
// Create the base arguments
accelerator := "tcg"
if driverConfig.Accelerator != "" {
accelerator = driverConfig.Accelerator
}
// TODO: Check a lower bounds, e.g. the default 128 of Qemu
mem := fmt.Sprintf("%dM", task.Resources.MemoryMB)
absPath, err := GetAbsolutePath("qemu-system-x86_64")
if err != nil {
return nil, err
}
args := []string{
absPath,
"-machine", "type=pc,accel=" + accelerator,
"-name", vmID,
"-m", mem,
"-drive", "file=" + vmPath,
"-nodefconfig",
"-nodefaults",
"-nographic",
}
// Check the Resources required Networks to add port mappings. If no resources
// are required, we assume the VM is a purely compute job and does not require
// the outside world to be able to reach it. VMs ran without port mappings can
// still reach out to the world, but without port mappings it is effectively
// firewalled
protocols := []string{"udp", "tcp"}
if len(task.Resources.Networks) > 0 && len(driverConfig.PortMap) == 1 {
// Loop through the port map and construct the hostfwd string, to map
// reserved ports to the ports listenting in the VM
// Ex: hostfwd=tcp::22000-:22,hostfwd=tcp::80-:8080
var forwarding []string
taskPorts := task.Resources.Networks[0].MapLabelToValues(nil)
for label, guest := range driverConfig.PortMap[0] {
host, ok := taskPorts[label]
if !ok {
return nil, fmt.Errorf("Unknown port label %q", label)
}
for _, p := range protocols {
forwarding = append(forwarding, fmt.Sprintf("hostfwd=%s::%d-:%d", p, host, guest))
}
}
if len(forwarding) != 0 {
args = append(args,
"-netdev",
fmt.Sprintf("user,id=user.0,%s", strings.Join(forwarding, ",")),
"-device", "virtio-net,netdev=user.0",
)
}
}
// If using KVM, add optimization args
if accelerator == "kvm" {
args = append(args,
"-enable-kvm",
"-cpu", "host",
// Do we have cores information available to the Driver?
// "-smp", fmt.Sprintf("%d", cores),
)
}
d.logger.Printf("[DEBUG] Starting QemuVM command: %q", strings.Join(args, " "))
bin, err := discover.NomadExecutable()
if err != nil {
return nil, fmt.Errorf("unable to find the nomad binary: %v", err)
}
pluginLogFile := filepath.Join(taskDir, fmt.Sprintf("%s-executor.out", task.Name))
pluginConfig := &plugin.ClientConfig{
Cmd: exec.Command(bin, "executor", pluginLogFile),
}
exec, pluginClient, err := createExecutor(pluginConfig, d.config.LogOutput, d.config)
if err != nil {
return nil, err
}
executorCtx := &executor.ExecutorContext{
TaskEnv: d.taskEnv,
Driver: "qemu",
AllocDir: ctx.AllocDir,
AllocID: ctx.AllocID,
Task: task,
}
ps, err := exec.LaunchCmd(&executor.ExecCommand{
Cmd: args[0],
Args: args[1:],
User: task.User,
}, executorCtx)
if err != nil {
pluginClient.Kill()
return nil, err
}
d.logger.Printf("[INFO] Started new QemuVM: %s", vmID)
// Create and Return Handle
maxKill := d.DriverContext.config.MaxKillTimeout
h := &qemuHandle{
pluginClient: pluginClient,
executor: exec,
userPid: ps.Pid,
allocDir: ctx.AllocDir,
killTimeout: GetKillTimeout(task.KillTimeout, maxKill),
maxKillTimeout: maxKill,
version: d.config.Version,
logger: d.logger,
doneCh: make(chan struct{}),
waitCh: make(chan *cstructs.WaitResult, 1),
}
if err := h.executor.SyncServices(consulContext(d.config, "")); err != nil {
h.logger.Printf("[ERR] driver.qemu: error registering services for task: %q: %v", task.Name, err)
}
go h.run()
return h, nil
}
type qemuId struct {
Version string
KillTimeout time.Duration
MaxKillTimeout time.Duration
UserPid int
PluginConfig *PluginReattachConfig
AllocDir *allocdir.AllocDir
}
func (d *QemuDriver) Open(ctx *ExecContext, handleID string) (DriverHandle, error) {
id := &qemuId{}
if err := json.Unmarshal([]byte(handleID), id); err != nil {
return nil, fmt.Errorf("Failed to parse handle '%s': %v", handleID, err)
}
pluginConfig := &plugin.ClientConfig{
Reattach: id.PluginConfig.PluginConfig(),
}
exec, pluginClient, err := createExecutor(pluginConfig, d.config.LogOutput, d.config)
if err != nil {
d.logger.Println("[ERR] driver.qemu: error connecting to plugin so destroying plugin pid and user pid")
if e := destroyPlugin(id.PluginConfig.Pid, id.UserPid); e != nil {
d.logger.Printf("[ERR] driver.qemu: error destroying plugin and userpid: %v", e)
}
return nil, fmt.Errorf("error connecting to plugin: %v", err)
}
ver, _ := exec.Version()
d.logger.Printf("[DEBUG] driver.qemu: version of executor: %v", ver.Version)
// Return a driver handle
h := &qemuHandle{
pluginClient: pluginClient,
executor: exec,
userPid: id.UserPid,
allocDir: id.AllocDir,
logger: d.logger,
killTimeout: id.KillTimeout,
maxKillTimeout: id.MaxKillTimeout,
version: id.Version,
doneCh: make(chan struct{}),
waitCh: make(chan *cstructs.WaitResult, 1),
}
if err := h.executor.SyncServices(consulContext(d.config, "")); err != nil {
h.logger.Printf("[ERR] driver.qemu: error registering services: %v", err)
}
go h.run()
return h, nil
}
func (h *qemuHandle) ID() string {
id := qemuId{
Version: h.version,
KillTimeout: h.killTimeout,
MaxKillTimeout: h.maxKillTimeout,
PluginConfig: NewPluginReattachConfig(h.pluginClient.ReattachConfig()),
UserPid: h.userPid,
AllocDir: h.allocDir,
}
data, err := json.Marshal(id)
if err != nil {
h.logger.Printf("[ERR] driver.qemu: failed to marshal ID to JSON: %s", err)
}
return string(data)
}
func (h *qemuHandle) WaitCh() chan *cstructs.WaitResult {
return h.waitCh
}
func (h *qemuHandle) Update(task *structs.Task) error {
// Store the updated kill timeout.
h.killTimeout = GetKillTimeout(task.KillTimeout, h.maxKillTimeout)
h.executor.UpdateTask(task)
// Update is not possible
return nil
}
// TODO: allow a 'shutdown_command' that can be executed over a ssh connection
// to the VM
func (h *qemuHandle) Kill() error {
if err := h.executor.ShutDown(); err != nil {
if h.pluginClient.Exited() {
return nil
}
return fmt.Errorf("executor Shutdown failed: %v", err)
}
select {
case <-h.doneCh:
return nil
case <-time.After(h.killTimeout):
if h.pluginClient.Exited() {
return nil
}
if err := h.executor.Exit(); err != nil {
return fmt.Errorf("executor Exit failed: %v", err)
}
return nil
}
}
func (h *qemuHandle) run() {
ps, err := h.executor.Wait()
if ps.ExitCode == 0 && err != nil {
if e := killProcess(h.userPid); e != nil {
h.logger.Printf("[ERR] driver.qemu: error killing user process: %v", e)
}
if e := h.allocDir.UnmountAll(); e != nil {
h.logger.Printf("[ERR] driver.qemu: unmounting dev,proc and alloc dirs failed: %v", e)
}
}
close(h.doneCh)
h.waitCh <- &cstructs.WaitResult{ExitCode: ps.ExitCode, Signal: ps.Signal, Err: err}
close(h.waitCh)
// Remove services
if err := h.executor.DeregisterServices(); err != nil {
h.logger.Printf("[ERR] driver.qemu: failed to deregister services: %v", err)
}
h.executor.Exit()
h.pluginClient.Kill()
}