Files
kata-containers/virtcontainers/device/drivers/vhost_user_blk.go
Wei Zhang 26a9b72c34 refactor: improve readability of bumpAttachCount
Fixes #1392

Improve code readability of function `device.bumpAttachCount`

Signed-off-by: Wei Zhang <zhangwei555@huawei.com>
2019-03-20 11:38:49 +08:00

76 lines
2.0 KiB
Go

// Copyright (c) 2017-2018 Intel Corporation
// Copyright (c) 2018 Huawei Corporation
//
// SPDX-License-Identifier: Apache-2.0
//
package drivers
import (
"encoding/hex"
"github.com/kata-containers/runtime/virtcontainers/device/api"
"github.com/kata-containers/runtime/virtcontainers/device/config"
"github.com/kata-containers/runtime/virtcontainers/utils"
)
// VhostUserBlkDevice is a block vhost-user based device
type VhostUserBlkDevice struct {
*GenericDevice
config.VhostUserDeviceAttrs
}
//
// VhostUserBlkDevice's implementation of the device interface:
//
// Attach is standard interface of api.Device, it's used to add device to some
// DeviceReceiver
func (device *VhostUserBlkDevice) Attach(devReceiver api.DeviceReceiver) (err error) {
skip, err := device.bumpAttachCount(true)
if err != nil {
return err
}
if skip {
return nil
}
defer func() {
if err != nil {
device.bumpAttachCount(false)
}
}()
// generate a unique ID to be used for hypervisor commandline fields
randBytes, err := utils.GenerateRandomBytes(8)
if err != nil {
return err
}
id := hex.EncodeToString(randBytes)
device.DevID = id
device.Type = device.DeviceType()
return devReceiver.AppendDevice(device)
}
// Detach is standard interface of api.Device, it's used to remove device from some
// DeviceReceiver
func (device *VhostUserBlkDevice) Detach(devReceiver api.DeviceReceiver) error {
_, err := device.bumpAttachCount(false)
return err
}
// DeviceType is standard interface of api.Device, it returns device type
func (device *VhostUserBlkDevice) DeviceType() config.DeviceType {
return config.VhostUserBlk
}
// GetDeviceInfo returns device information used for creating
func (device *VhostUserBlkDevice) GetDeviceInfo() interface{} {
device.Type = device.DeviceType()
return &device.VhostUserDeviceAttrs
}
// It should implement GetAttachCount() and DeviceID() as api.Device implementation
// here it shares function from *GenericDevice so we don't need duplicate codes