// Init creates a driver with the given home and the set of options.
func Init(home string, options []string) (graphdriver.Driver, error) {
fsMagic, err := graphdriver.GetFSMagic(home)
if err != nil {
return nil, err
}
if fsName, ok := graphdriver.FsNames[fsMagic]; ok {
backingFs = fsName
}
deviceSet, err := NewDeviceSet(home, true, options)
if err != nil {
return nil, err
}
if err := mount.MakePrivate(home); err != nil {
return nil, err
}
d := &Driver{
DeviceSet: deviceSet,
home: home,
}
return graphdriver.NaiveDiffDriver(d), nil
}
// Init returns the NaiveDiffDriver, a native diff driver for overlay filesystem.
// If overlay filesystem is not supported on the host, graphdriver.ErrNotSupported is returned as error.
// If a overlay filesystem is not supported over a existing filesystem then error graphdriver.ErrIncompatibleFS is returned.
func Init(home string, options []string) (graphdriver.Driver, error) {
if err := supportsOverlay(); err != nil {
return nil, graphdriver.ErrNotSupported
}
fsMagic, err := graphdriver.GetFSMagic(home)
if err != nil {
return nil, err
}
if fsName, ok := graphdriver.FsNames[fsMagic]; ok {
backingFs = fsName
}
// check if they are running over btrfs or aufs
switch fsMagic {
case graphdriver.FsMagicBtrfs:
logrus.Error("'overlay' is not supported over btrfs.")
return nil, graphdriver.ErrIncompatibleFS
case graphdriver.FsMagicAufs:
logrus.Error("'overlay' is not supported over aufs.")
return nil, graphdriver.ErrIncompatibleFS
case graphdriver.FsMagicZfs:
logrus.Error("'overlay' is not supported over zfs.")
return nil, graphdriver.ErrIncompatibleFS
}
// Create the driver home dir
if err := os.MkdirAll(home, 0755); err != nil {
return nil, err
}
d := &Driver{
home: home,
active: make(map[string]*ActiveMount),
}
return NaiveDiffDriverWithApply(d), nil
}