// Init returns the 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, uidMaps, gidMaps []idtools.IDMap) (graphdriver.Driver, error) {
opts, err := parseOptions(options)
if err != nil {
return nil, err
}
if err := supportsOverlay(); err != nil {
return nil, graphdriver.ErrNotSupported
}
// require kernel 4.0.0 to ensure multiple lower dirs are supported
v, err := kernel.GetKernelVersion()
if err != nil {
return nil, err
}
if kernel.CompareKernelVersion(*v, kernel.VersionInfo{Kernel: 4, Major: 0, Minor: 0}) < 0 {
if !opts.overrideKernelCheck {
return nil, graphdriver.ErrNotSupported
}
logrus.Warnf("Using pre-4.0.0 kernel for overlay2, mount failures may require kernel update")
}
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, aufs, zfs, overlay, or ecryptfs
switch fsMagic {
case graphdriver.FsMagicBtrfs, graphdriver.FsMagicAufs, graphdriver.FsMagicZfs, graphdriver.FsMagicOverlay, graphdriver.FsMagicEcryptfs:
logrus.Errorf("'overlay2' is not supported over %s", backingFs)
return nil, graphdriver.ErrIncompatibleFS
}
rootUID, rootGID, err := idtools.GetRootUIDGID(uidMaps, gidMaps)
if err != nil {
return nil, err
}
// Create the driver home dir
if err := idtools.MkdirAllAs(path.Join(home, linkDir), 0700, rootUID, rootGID); err != nil && !os.IsExist(err) {
return nil, err
}
if err := mount.MakePrivate(home); err != nil {
return nil, err
}
d := &Driver{
home: home,
uidMaps: uidMaps,
gidMaps: gidMaps,
ctr: graphdriver.NewRefCounter(graphdriver.NewFsChecker(graphdriver.FsMagicOverlay)),
}
return d, nil
}
func checkKernelVersion(k, major, minor int) bool {
if v, err := kernel.GetKernelVersion(); err != nil {
logrus.Warnf("%s", err)
} else {
if kernel.CompareKernelVersion(*v, kernel.VersionInfo{Kernel: k, Major: major, Minor: minor}) < 0 {
return false
}
}
return true
}
func overlay2Supported() bool {
if !overlayFSSupported() {
return false
}
daemonV, err := kernel.ParseRelease(daemonKernelVersion)
if err != nil {
return false
}
requiredV := kernel.VersionInfo{Kernel: 4}
return kernel.CompareKernelVersion(*daemonV, requiredV) > -1
}
func checkKernel(k, major, minor int) error {
leastVersionInfo := kernel.VersionInfo{
Kernel: k,
Major: major,
Minor: minor,
}
if v, err := kernel.GetKernelVersion(); err != nil {
return err
} else {
if kernel.CompareKernelVersion(*v, leastVersionInfo) < 0 {
msg := fmt.Sprintf("Your Linux kernel(%d.%d.%d) is too old to support Hyper daemon(%d.%d.%d+)",
v.Kernel, v.Major, v.Minor, k, major, minor)
return fmt.Errorf(msg)
}
return nil
}
}
func checkSystem() error {
// check OS version for compatibility, ensure running in global zone
var err error
var id C.zoneid_t
if id, err = C.getzoneid(); err != nil {
return fmt.Errorf("Exiting. Error getting zone id: %+v", err)
}
if int(id) != 0 {
return fmt.Errorf("Exiting because the Docker daemon is not running in the global zone")
}
v, err := kernel.GetKernelVersion()
if kernel.CompareKernelVersion(*v, kernel.VersionInfo{Kernel: 5, Major: 12, Minor: 0}) < 0 {
return fmt.Errorf("Your Solaris kernel version: %s doesn't support Docker. Please upgrade to 5.12.0", v.String())
}
return err
}
func checkKernel() error {
// Check for unsupported kernel versions
// FIXME: it would be cleaner to not test for specific versions, but rather
// test for specific functionalities.
// Unfortunately we can't test for the feature "does not cause a kernel panic"
// without actually causing a kernel panic, so we need this workaround until
// the circumstances of pre-3.10 crashes are clearer.
// For details see https://github.com/docker/docker/issues/407
if k, err := kernel.GetKernelVersion(); err != nil {
logrus.Warnf("%s", err)
} else {
if kernel.CompareKernelVersion(k, &kernel.KernelVersionInfo{Kernel: 3, Major: 10, Minor: 0}) < 0 {
if os.Getenv("DOCKER_NOWARN_KERNEL_VERSION") == "" {
logrus.Warnf("You are running linux kernel version %s, which might be unstable running docker. Please upgrade your kernel to 3.10.0.", k.String())
}
}
}
return nil
}
func checkKernelAndArch() error {
// Check for unsupported architectures
if runtime.GOARCH != "amd64" {
return fmt.Errorf("The Docker runtime currently only supports amd64 (not %s). This will change in the future. Aborting.", runtime.GOARCH)
}
// Check for unsupported kernel versions
// FIXME: it would be cleaner to not test for specific versions, but rather
// test for specific functionalities.
// Unfortunately we can't test for the feature "does not cause a kernel panic"
// without actually causing a kernel panic, so we need this workaround until
// the circumstances of pre-3.8 crashes are clearer.
// For details see http://github.com/docker/docker/issues/407
if k, err := kernel.GetKernelVersion(); err != nil {
log.Infof("WARNING: %s", err)
} else {
if kernel.CompareKernelVersion(k, &kernel.KernelVersionInfo{Kernel: 3, Major: 8, Minor: 0}) < 0 {
if os.Getenv("DOCKER_NOWARN_KERNEL_VERSION") == "" {
log.Infof("WARNING: You are running linux kernel version %s, which might be unstable running docker. Please upgrade your kernel to 3.8.0.", k.String())
}
}
}
return nil
}
cmd := exec.Command(dockerBinary, "run", "--rm", "busybox", "/bin/sh", "-c", "cat /proc/filesystems")
out, err := cmd.CombinedOutput()
if err != nil {
return false
}
return bytes.Contains(out, []byte("overlay\n"))
},
"Test cannot be run without suppport for overlayfs",
}
overlay2Supported = testRequirement{
func() bool {
if !overlayFSSupported.Condition() {
return false
}
daemonV, err := kernel.ParseRelease(daemonKernelVersion)
if err != nil {
return false
}
requiredV := kernel.VersionInfo{Kernel: 4}
return kernel.CompareKernelVersion(*daemonV, requiredV) > -1
},
"Test cannot be run without overlay2 support (kernel 4.0+)",
}
)
func init() {
SysInfo = sysinfo.New(true)
}
// Init returns the a native diff driver for overlay filesystem.
// If overlay filesystem is not supported on the host, graphdriver.ErrNotSupported is returned as error.
// If an overlay filesystem is not supported over an existing filesystem then error graphdriver.ErrIncompatibleFS is returned.
func Init(home string, options []string, uidMaps, gidMaps []idtools.IDMap) (graphdriver.Driver, error) {
opts, err := parseOptions(options)
if err != nil {
return nil, err
}
if err := supportsOverlay(); err != nil {
return nil, graphdriver.ErrNotSupported
}
// require kernel 4.0.0 to ensure multiple lower dirs are supported
v, err := kernel.GetKernelVersion()
if err != nil {
return nil, err
}
if kernel.CompareKernelVersion(*v, kernel.VersionInfo{Kernel: 4, Major: 0, Minor: 0}) < 0 {
if !opts.overrideKernelCheck {
return nil, graphdriver.ErrNotSupported
}
logrus.Warn("Using pre-4.0.0 kernel for overlay2, mount failures may require kernel update")
}
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, aufs, zfs, overlay, or ecryptfs
switch fsMagic {
case graphdriver.FsMagicBtrfs, graphdriver.FsMagicAufs, graphdriver.FsMagicZfs, graphdriver.FsMagicOverlay, graphdriver.FsMagicEcryptfs:
logrus.Errorf("'overlay2' is not supported over %s", backingFs)
return nil, graphdriver.ErrIncompatibleFS
}
rootUID, rootGID, err := idtools.GetRootUIDGID(uidMaps, gidMaps)
if err != nil {
return nil, err
}
// Create the driver home dir
if err := idtools.MkdirAllAs(path.Join(home, linkDir), 0700, rootUID, rootGID); err != nil && !os.IsExist(err) {
return nil, err
}
if err := mount.MakePrivate(home); err != nil {
return nil, err
}
supportsDType, err := fsutils.SupportsDType(home)
if err != nil {
return nil, err
}
if !supportsDType {
// not a fatal error until v1.16 (#27443)
logrus.Warn(overlayutils.ErrDTypeNotSupported("overlay2", backingFs))
}
d := &Driver{
home: home,
uidMaps: uidMaps,
gidMaps: gidMaps,
ctr: graphdriver.NewRefCounter(graphdriver.NewFsChecker(graphdriver.FsMagicOverlay)),
supportsDType: supportsDType,
}
d.naiveDiff = graphdriver.NewNaiveDiffDriver(d, uidMaps, gidMaps)
if backingFs == "xfs" {
// Try to enable project quota support over xfs.
if d.quotaCtl, err = quota.NewControl(home); err == nil {
projectQuotaSupported = true
}
}
logrus.Debugf("backingFs=%s, projectQuotaSupported=%v", backingFs, projectQuotaSupported)
return d, nil
}