diff --git a/components/engine/daemon/graphdriver/devmapper/deviceset.go b/components/engine/daemon/graphdriver/devmapper/deviceset.go index a2cb0c330e..31e5042292 100644 --- a/components/engine/daemon/graphdriver/devmapper/deviceset.go +++ b/components/engine/daemon/graphdriver/devmapper/deviceset.go @@ -528,7 +528,7 @@ func (devices *DeviceSet) activateDeviceIfNeeded(info *devInfo, ignoreDeleted bo // Make sure deferred removal on device is canceled, if one was // scheduled. - if err := devices.cancelDeferredRemoval(info); err != nil { + if err := devices.cancelDeferredRemovalIfNeeded(info); err != nil { return fmt.Errorf("devmapper: Device Deferred Removal Cancellation Failed: %s", err) } @@ -841,11 +841,56 @@ func (devices *DeviceSet) createRegisterDevice(hash string) (*devInfo, error) { return info, nil } -func (devices *DeviceSet) createRegisterSnapDevice(hash string, baseInfo *devInfo, size uint64) error { - if err := devices.poolHasFreeSpace(); err != nil { +func (devices *DeviceSet) takeSnapshot(hash string, baseInfo *devInfo, size uint64) error { + var ( + devinfo *devicemapper.Info + err error + ) + + if err = devices.poolHasFreeSpace(); err != nil { return err } + if devices.deferredRemove { + devinfo, err = devicemapper.GetInfoWithDeferred(baseInfo.Name()) + if err != nil { + return err + } + if devinfo != nil && devinfo.DeferredRemove != 0 { + err = devices.cancelDeferredRemoval(baseInfo) + if err != nil { + // If Error is ErrEnxio. Device is probably already gone. Continue. + if err != devicemapper.ErrEnxio { + return err + } + } else { + defer devices.deactivateDevice(baseInfo) + } + } + } else { + devinfo, err = devicemapper.GetInfo(baseInfo.Name()) + if err != nil { + return err + } + } + + doSuspend := devinfo != nil && devinfo.Exists != 0 + + if doSuspend { + if err = devicemapper.SuspendDevice(baseInfo.Name()); err != nil { + return err + } + defer devicemapper.ResumeDevice(baseInfo.Name()) + } + + if err = devices.createRegisterSnapDevice(hash, baseInfo, size); err != nil { + return err + } + + return nil +} + +func (devices *DeviceSet) createRegisterSnapDevice(hash string, baseInfo *devInfo, size uint64) error { deviceID, err := devices.getNextFreeDeviceID() if err != nil { return err @@ -858,7 +903,7 @@ func (devices *DeviceSet) createRegisterSnapDevice(hash string, baseInfo *devInf } for { - if err := devicemapper.CreateSnapDevice(devices.getPoolDevName(), deviceID, baseInfo.Name(), baseInfo.DeviceID); err != nil { + if err := devicemapper.CreateSnapDeviceRaw(devices.getPoolDevName(), deviceID, baseInfo.DeviceID); err != nil { if devicemapper.DeviceIDExists(err) { // Device ID already exists. This should not // happen. Now we have a mechanism to find @@ -1886,7 +1931,7 @@ func (devices *DeviceSet) AddDevice(hash, baseHash string, storageOpt map[string return fmt.Errorf("devmapper: Container size cannot be smaller than %s", units.HumanSize(float64(baseInfo.Size))) } - if err := devices.createRegisterSnapDevice(hash, baseInfo, size); err != nil { + if err := devices.takeSnapshot(hash, baseInfo, size); err != nil { return err } @@ -2128,41 +2173,53 @@ func (devices *DeviceSet) removeDevice(devname string) error { return err } -func (devices *DeviceSet) cancelDeferredRemoval(info *devInfo) error { +func (devices *DeviceSet) cancelDeferredRemovalIfNeeded(info *devInfo) error { if !devices.deferredRemove { return nil } - logrus.Debugf("devmapper: cancelDeferredRemoval START(%s)", info.Name()) - defer logrus.Debugf("devmapper: cancelDeferredRemoval END(%s)", info.Name()) + logrus.Debugf("devmapper: cancelDeferredRemovalIfNeeded START(%s)", info.Name()) + defer logrus.Debugf("devmapper: cancelDeferredRemovalIfNeeded END(%s)", info.Name()) devinfo, err := devicemapper.GetInfoWithDeferred(info.Name()) + if err != nil { + return err + } if devinfo != nil && devinfo.DeferredRemove == 0 { return nil } // Cancel deferred remove - for i := 0; i < 100; i++ { - err = devicemapper.CancelDeferredRemove(info.Name()) - if err == nil { - break - } - - if err == devicemapper.ErrEnxio { - // Device is probably already gone. Return success. - return nil - } - - if err != devicemapper.ErrBusy { + if err := devices.cancelDeferredRemoval(info); err != nil { + // If Error is ErrEnxio. Device is probably already gone. Continue. + if err != devicemapper.ErrEnxio { return err } + } + return nil +} - // If we see EBUSY it may be a transient error, - // sleep a bit a retry a few times. - devices.Unlock() - time.Sleep(100 * time.Millisecond) - devices.Lock() +func (devices *DeviceSet) cancelDeferredRemoval(info *devInfo) error { + logrus.Debugf("devmapper: cancelDeferredRemoval START(%s)", info.Name()) + defer logrus.Debugf("devmapper: cancelDeferredRemoval END(%s)", info.Name()) + + var err error + + // Cancel deferred remove + for i := 0; i < 100; i++ { + err = devicemapper.CancelDeferredRemove(info.Name()) + if err != nil { + if err == devicemapper.ErrBusy { + // If we see EBUSY it may be a transient error, + // sleep a bit a retry a few times. + devices.Unlock() + time.Sleep(100 * time.Millisecond) + devices.Lock() + continue + } + } + break } return err } diff --git a/components/engine/pkg/devicemapper/devmapper.go b/components/engine/pkg/devicemapper/devmapper.go index 838b06af40..d6b17ad976 100644 --- a/components/engine/pkg/devicemapper/devmapper.go +++ b/components/engine/pkg/devicemapper/devmapper.go @@ -750,6 +750,33 @@ func activateDevice(poolName string, name string, deviceID int, size uint64, ext return nil } +// CreateSnapDeviceRaw creates a snapshot device. Caller needs to suspend and resume the origin device if it is active. +func CreateSnapDeviceRaw(poolName string, deviceID int, baseDeviceID int) error { + task, err := TaskCreateNamed(deviceTargetMsg, poolName) + if task == nil { + return err + } + + if err := task.setSector(0); err != nil { + return fmt.Errorf("devicemapper: Can't set sector %s", err) + } + + if err := task.setMessage(fmt.Sprintf("create_snap %d %d", deviceID, baseDeviceID)); err != nil { + return fmt.Errorf("devicemapper: Can't set message %s", err) + } + + dmSawExist = false // reset before the task is run + if err := task.run(); err != nil { + // Caller wants to know about ErrDeviceIDExists so that it can try with a different device id. + if dmSawExist { + return ErrDeviceIDExists + } + return fmt.Errorf("devicemapper: Error running deviceCreate (createSnapDevice) %s", err) + } + + return nil +} + // CreateSnapDevice creates a snapshot based on the device identified by the baseName and baseDeviceId, func CreateSnapDevice(poolName string, deviceID int, baseName string, baseDeviceID int) error { devinfo, _ := GetInfo(baseName) @@ -761,42 +788,15 @@ func CreateSnapDevice(poolName string, deviceID int, baseName string, baseDevice } } - task, err := TaskCreateNamed(deviceTargetMsg, poolName) - if task == nil { + if err := CreateSnapDeviceRaw(poolName, deviceID, baseDeviceID); err != nil { if doSuspend { - ResumeDevice(baseName) + if err2 := ResumeDevice(baseName); err2 != nil { + return fmt.Errorf("CreateSnapDeviceRaw Error: (%v): ResumeDevice Error: (%v)", err, err2) + } } return err } - if err := task.setSector(0); err != nil { - if doSuspend { - ResumeDevice(baseName) - } - return fmt.Errorf("devicemapper: Can't set sector %s", err) - } - - if err := task.setMessage(fmt.Sprintf("create_snap %d %d", deviceID, baseDeviceID)); err != nil { - if doSuspend { - ResumeDevice(baseName) - } - return fmt.Errorf("devicemapper: Can't set message %s", err) - } - - dmSawExist = false // reset before the task is run - if err := task.run(); err != nil { - if doSuspend { - ResumeDevice(baseName) - } - // Caller wants to know about ErrDeviceIDExists so that it can try with a different device id. - if dmSawExist { - return ErrDeviceIDExists - } - - return fmt.Errorf("devicemapper: Error running deviceCreate (createSnapDevice) %s", err) - - } - if doSuspend { if err := ResumeDevice(baseName); err != nil { return err