Documentation

Overview

    Package mount defines an interface to mounting filesystems.

    TODO(thockin): This whole pkg is pretty linux-centric. As soon as we have an alternate platform, we will need to abstract further.

    Index

    Constants

    View Source
    const FakeActionMount = "mount"

      Values for FakeAction.Action

      View Source
      const FakeActionUnmount = "unmount"

      Variables

      This section is empty.

      Functions

      func CleanupMountPoint

      func CleanupMountPoint(mountPath string, mounter Interface, extensiveMountPointCheck bool) error

        CleanupMountPoint unmounts the given path and deletes the remaining directory if successful. if extensiveMountPointCheck is true IsNotMountPoint will be called instead of IsLikelyNotMountPoint. IsNotMountPoint is more expensive but properly handles bind mounts within the same fs.

        func GetDeviceNameFromMount

        func GetDeviceNameFromMount(mounter Interface, mountPath string) (string, int, error)

          GetDeviceNameFromMount: given a mnt point, find the device from /proc/mounts returns the device name, reference count, and error code

          func HasMountRefs

          func HasMountRefs(mountPath string, mountRefs []string) bool

          func IsCorruptedMnt

          func IsCorruptedMnt(err error) bool

            IsCorruptedMnt return true if err is about corrupted mount point

            func PathExists

            func PathExists(path string) (bool, error)

              TODO: clean this up to use pkg/util/file/FileExists PathExists returns true if the specified path exists.

              func PathWithinBase

              func PathWithinBase(fullPath, basePath string) bool

                PathWithinBase checks if give path is within given base directory.

                func StartsWithBackstep

                func StartsWithBackstep(rel string) bool

                  StartsWithBackstep checks if the given path starts with a backstep segment

                  Types

                  type Exec

                  type Exec interface {
                  	// Run executes a command and returns its stdout + stderr combined in one
                  	// stream.
                  	Run(cmd string, args ...string) ([]byte, error)
                  }

                    Exec executes command where mount utilities are. This can be either the host, container where kubelet runs or even a remote pod with mount utilities. Usual k8s.io/utils/exec interface is not used because kubelet.RunInContainer does not provide stdin/stdout/stderr streams.

                    func NewOsExec

                    func NewOsExec() Exec

                    type FakeAction

                    type FakeAction struct {
                    	Action string // "mount" or "unmount"
                    	Target string // applies to both mount and unmount actions
                    	Source string // applies only to "mount" actions
                    	FSType string // applies only to "mount" actions
                    }

                      FakeAction objects are logged every time a fake mount or unmount is called.

                      type FakeExec

                      type FakeExec struct {
                      	// contains filtered or unexported fields
                      }

                        Fake for testing.

                        func NewFakeExec

                        func NewFakeExec(run runHook) *FakeExec

                        func (*FakeExec) Run

                        func (f *FakeExec) Run(cmd string, args ...string) ([]byte, error)

                        type FakeMounter

                        type FakeMounter struct {
                        	MountPoints []MountPoint
                        	Log         []FakeAction
                        	Filesystem  map[string]FileType
                        	// Error to return for a path when calling IsLikelyNotMountPoint
                        	MountCheckErrors map[string]error
                        	// contains filtered or unexported fields
                        }

                          FakeMounter implements mount.Interface for tests.

                          func (*FakeMounter) DeviceOpened

                          func (f *FakeMounter) DeviceOpened(pathname string) (bool, error)
                          func (f *FakeMounter) EvalHostSymlinks(pathname string) (string, error)

                          func (*FakeMounter) ExistsPath

                          func (f *FakeMounter) ExistsPath(pathname string) (bool, error)

                          func (*FakeMounter) GetDeviceNameFromMount

                          func (f *FakeMounter) GetDeviceNameFromMount(mountPath, pluginDir string) (string, error)

                          func (*FakeMounter) GetFSGroup

                          func (f *FakeMounter) GetFSGroup(pathname string) (int64, error)

                          func (*FakeMounter) GetFileType

                          func (f *FakeMounter) GetFileType(pathname string) (FileType, error)

                          func (*FakeMounter) GetMode

                          func (f *FakeMounter) GetMode(pathname string) (os.FileMode, error)

                          func (*FakeMounter) GetMountRefs

                          func (f *FakeMounter) GetMountRefs(pathname string) ([]string, error)

                          func (*FakeMounter) GetSELinuxSupport

                          func (f *FakeMounter) GetSELinuxSupport(pathname string) (bool, error)

                          func (*FakeMounter) IsLikelyNotMountPoint

                          func (f *FakeMounter) IsLikelyNotMountPoint(file string) (bool, error)

                          func (*FakeMounter) IsMountPointMatch

                          func (f *FakeMounter) IsMountPointMatch(mp MountPoint, dir string) bool

                          func (*FakeMounter) IsNotMountPoint

                          func (f *FakeMounter) IsNotMountPoint(dir string) (bool, error)

                          func (*FakeMounter) List

                          func (f *FakeMounter) List() ([]MountPoint, error)

                          func (*FakeMounter) MakeDir

                          func (f *FakeMounter) MakeDir(pathname string) error

                          func (*FakeMounter) MakeFile

                          func (f *FakeMounter) MakeFile(pathname string) error

                          func (*FakeMounter) MakeRShared

                          func (f *FakeMounter) MakeRShared(path string) error

                          func (*FakeMounter) Mount

                          func (f *FakeMounter) Mount(source string, target string, fstype string, options []string) error

                          func (*FakeMounter) PathIsDevice

                          func (f *FakeMounter) PathIsDevice(pathname string) (bool, error)

                          func (*FakeMounter) ResetLog

                          func (f *FakeMounter) ResetLog()

                          func (*FakeMounter) Unmount

                          func (f *FakeMounter) Unmount(target string) error

                          type FileType

                          type FileType string
                          const (
                          	MountsInGlobalPDPath          = "mounts"
                          	FileTypeDirectory    FileType = "Directory"
                          	FileTypeFile         FileType = "File"
                          	FileTypeSocket       FileType = "Socket"
                          	FileTypeCharDev      FileType = "CharDevice"
                          	FileTypeBlockDev     FileType = "BlockDevice"
                          )

                          type Interface

                          type Interface interface {
                          	// Mount mounts source to target as fstype with given options.
                          	Mount(source string, target string, fstype string, options []string) error
                          	// Unmount unmounts given target.
                          	Unmount(target string) error
                          	// List returns a list of all mounted filesystems.  This can be large.
                          	// On some platforms, reading mounts is not guaranteed consistent (i.e.
                          	// it could change between chunked reads). This is guaranteed to be
                          	// consistent.
                          	List() ([]MountPoint, error)
                          	// IsMountPointMatch determines if the mountpoint matches the dir
                          	IsMountPointMatch(mp MountPoint, dir string) bool
                          	// IsNotMountPoint determines if a directory is a mountpoint.
                          	// It should return ErrNotExist when the directory does not exist.
                          	// IsNotMountPoint is more expensive than IsLikelyNotMountPoint.
                          	// IsNotMountPoint detects bind mounts in linux.
                          	// IsNotMountPoint enumerates all the mountpoints using List() and
                          	// the list of mountpoints may be large, then it uses
                          	// IsMountPointMatch to evaluate whether the directory is a mountpoint
                          	IsNotMountPoint(file string) (bool, error)
                          	// IsLikelyNotMountPoint uses heuristics to determine if a directory
                          	// is a mountpoint.
                          	// It should return ErrNotExist when the directory does not exist.
                          	// IsLikelyNotMountPoint does NOT properly detect all mountpoint types
                          	// most notably linux bind mounts.
                          	IsLikelyNotMountPoint(file string) (bool, error)
                          	// DeviceOpened determines if the device is in use elsewhere
                          	// on the system, i.e. still mounted.
                          	DeviceOpened(pathname string) (bool, error)
                          	// PathIsDevice determines if a path is a device.
                          	PathIsDevice(pathname string) (bool, error)
                          	// GetDeviceNameFromMount finds the device name by checking the mount path
                          	// to get the global mount path which matches its plugin directory
                          	GetDeviceNameFromMount(mountPath, pluginDir string) (string, error)
                          	// MakeRShared checks that given path is on a mount with 'rshared' mount
                          	// propagation. If not, it bind-mounts the path as rshared.
                          	MakeRShared(path string) error
                          	// GetFileType checks for file/directory/socket/block/character devices.
                          	// Will operate in the host mount namespace if kubelet is running in a container
                          	GetFileType(pathname string) (FileType, error)
                          	// MakeFile creates an empty file.
                          	// Will operate in the host mount namespace if kubelet is running in a container
                          	MakeFile(pathname string) error
                          	// MakeDir creates a new directory.
                          	// Will operate in the host mount namespace if kubelet is running in a container
                          	MakeDir(pathname string) error
                          	// Will operate in the host mount namespace if kubelet is running in a container.
                          	// Error is returned on any other error than "file not found".
                          	ExistsPath(pathname string) (bool, error)
                          	// EvalHostSymlinks returns the path name after evaluating symlinks.
                          	// Will operate in the host mount namespace if kubelet is running in a container.
                          	EvalHostSymlinks(pathname string) (string, error)
                          	// GetMountRefs finds all mount references to the path, returns a
                          	// list of paths. Path could be a mountpoint path, device or a normal
                          	// directory (for bind mount).
                          	GetMountRefs(pathname string) ([]string, error)
                          	// GetFSGroup returns FSGroup of the path.
                          	GetFSGroup(pathname string) (int64, error)
                          	// GetSELinuxSupport returns true if given path is on a mount that supports
                          	// SELinux.
                          	GetSELinuxSupport(pathname string) (bool, error)
                          	// GetMode returns permissions of the path.
                          	GetMode(pathname string) (os.FileMode, error)
                          }

                          func New

                          func New(mounterPath string) Interface

                            New returns a mount.Interface for the current system. It provides options to override the default mounter behavior. mounterPath allows using an alternative to `/bin/mount` for mounting.

                            func NewExecMounter

                            func NewExecMounter(exec Exec, wrapped Interface) Interface

                            type MountPoint

                            type MountPoint struct {
                            	Device string
                            	Path   string
                            	Type   string
                            	Opts   []string
                            	Freq   int
                            	Pass   int
                            }

                              This represents a single line in /proc/mounts or /etc/fstab.

                              type Mounter

                              type Mounter struct {
                              	// contains filtered or unexported fields
                              }

                                Mounter provides the default implementation of mount.Interface for the linux platform. This implementation assumes that the kubelet is running in the host's root mount namespace.

                                func (*Mounter) DeviceOpened

                                func (mounter *Mounter) DeviceOpened(pathname string) (bool, error)

                                  DeviceOpened checks if block device in use by calling Open with O_EXCL flag. If pathname is not a device, log and return false with nil error. If open returns errno EBUSY, return true with nil error. If open returns nil, return false with nil error. Otherwise, return false with error

                                  func (mounter *Mounter) EvalHostSymlinks(pathname string) (string, error)

                                  func (*Mounter) ExistsPath

                                  func (mounter *Mounter) ExistsPath(pathname string) (bool, error)

                                  func (*Mounter) GetDeviceNameFromMount

                                  func (mounter *Mounter) GetDeviceNameFromMount(mountPath, pluginDir string) (string, error)

                                    GetDeviceNameFromMount: given a mount point, find the device name from its global mount point

                                    func (*Mounter) GetFSGroup

                                    func (mounter *Mounter) GetFSGroup(pathname string) (int64, error)

                                    func (*Mounter) GetFileType

                                    func (mounter *Mounter) GetFileType(pathname string) (FileType, error)

                                    func (*Mounter) GetMode

                                    func (mounter *Mounter) GetMode(pathname string) (os.FileMode, error)

                                    func (*Mounter) GetMountRefs

                                    func (mounter *Mounter) GetMountRefs(pathname string) ([]string, error)

                                    func (*Mounter) GetSELinuxSupport

                                    func (mounter *Mounter) GetSELinuxSupport(pathname string) (bool, error)

                                    func (*Mounter) IsLikelyNotMountPoint

                                    func (mounter *Mounter) IsLikelyNotMountPoint(file string) (bool, error)

                                      IsLikelyNotMountPoint determines if a directory is not a mountpoint. It is fast but not necessarily ALWAYS correct. If the path is in fact a bind mount from one part of a mount to another it will not be detected. mkdir /tmp/a /tmp/b; mount --bin /tmp/a /tmp/b; IsLikelyNotMountPoint("/tmp/b") will return true. When in fact /tmp/b is a mount point. If this situation if of interest to you, don't use this function...

                                      func (*Mounter) IsMountPointMatch

                                      func (mounter *Mounter) IsMountPointMatch(mp MountPoint, dir string) bool

                                      func (*Mounter) IsNotMountPoint

                                      func (mounter *Mounter) IsNotMountPoint(dir string) (bool, error)

                                      func (*Mounter) List

                                      func (*Mounter) List() ([]MountPoint, error)

                                        List returns a list of all mounted filesystems.

                                        func (*Mounter) MakeDir

                                        func (mounter *Mounter) MakeDir(pathname string) error

                                        func (*Mounter) MakeFile

                                        func (mounter *Mounter) MakeFile(pathname string) error

                                        func (*Mounter) MakeRShared

                                        func (mounter *Mounter) MakeRShared(path string) error

                                        func (*Mounter) Mount

                                        func (mounter *Mounter) Mount(source string, target string, fstype string, options []string) error

                                          Mount mounts source to target as fstype with given options. 'source' and 'fstype' must be an empty string in case it's not required, e.g. for remount, or for auto filesystem type, where kernel handles fstype for you. The mount 'options' is a list of options, currently come from mount(8), e.g. "ro", "remount", "bind", etc. If no more option is required, call Mount with an empty string list or nil.

                                          func (*Mounter) PathIsDevice

                                          func (mounter *Mounter) PathIsDevice(pathname string) (bool, error)

                                            PathIsDevice uses FileInfo returned from os.Stat to check if path refers to a device.

                                            func (*Mounter) Unmount

                                            func (mounter *Mounter) Unmount(target string) error

                                              Unmount unmounts the target.

                                              type NsenterMounter

                                              type NsenterMounter struct {
                                              	// contains filtered or unexported fields
                                              }

                                                Currently, all docker containers receive their own mount namespaces. NsenterMounter works by executing nsenter to run commands in the host's mount namespace.

                                                func NewNsenterMounter

                                                func NewNsenterMounter(rootDir string, ne *nsenter.Nsenter) *NsenterMounter

                                                  NewNsenterMounter creates a new mounter for kubelet that runs as a container.

                                                  func (*NsenterMounter) DeviceOpened

                                                  func (n *NsenterMounter) DeviceOpened(pathname string) (bool, error)

                                                    DeviceOpened checks if block device in use by calling Open with O_EXCL flag. Returns true if open returns errno EBUSY, and false if errno is nil. Returns an error if errno is any error other than EBUSY. Returns with error if pathname is not a device.

                                                    func (mounter *NsenterMounter) EvalHostSymlinks(pathname string) (string, error)

                                                    func (*NsenterMounter) ExistsPath

                                                    func (mounter *NsenterMounter) ExistsPath(pathname string) (bool, error)

                                                    func (*NsenterMounter) GetDeviceNameFromMount

                                                    func (n *NsenterMounter) GetDeviceNameFromMount(mountPath, pluginDir string) (string, error)

                                                      GetDeviceNameFromMount given a mount point, find the volume id from checking /proc/mounts

                                                      func (*NsenterMounter) GetFSGroup

                                                      func (mounter *NsenterMounter) GetFSGroup(pathname string) (int64, error)

                                                      func (*NsenterMounter) GetFileType

                                                      func (mounter *NsenterMounter) GetFileType(pathname string) (FileType, error)

                                                      func (*NsenterMounter) GetMode

                                                      func (mounter *NsenterMounter) GetMode(pathname string) (os.FileMode, error)

                                                      func (*NsenterMounter) GetMountRefs

                                                      func (mounter *NsenterMounter) GetMountRefs(pathname string) ([]string, error)

                                                      func (*NsenterMounter) GetSELinuxSupport

                                                      func (mounter *NsenterMounter) GetSELinuxSupport(pathname string) (bool, error)

                                                      func (*NsenterMounter) IsLikelyNotMountPoint

                                                      func (n *NsenterMounter) IsLikelyNotMountPoint(file string) (bool, error)

                                                        IsLikelyNotMountPoint determines whether a path is a mountpoint by calling findmnt in the host's root mount namespace.

                                                        func (*NsenterMounter) IsMountPointMatch

                                                        func (*NsenterMounter) IsMountPointMatch(mp MountPoint, dir string) bool

                                                        func (*NsenterMounter) IsNotMountPoint

                                                        func (m *NsenterMounter) IsNotMountPoint(dir string) (bool, error)

                                                        func (*NsenterMounter) List

                                                        func (*NsenterMounter) List() ([]MountPoint, error)

                                                          List returns a list of all mounted filesystems in the host's mount namespace.

                                                          func (*NsenterMounter) MakeDir

                                                          func (mounter *NsenterMounter) MakeDir(pathname string) error

                                                          func (*NsenterMounter) MakeFile

                                                          func (mounter *NsenterMounter) MakeFile(pathname string) error

                                                          func (*NsenterMounter) MakeRShared

                                                          func (n *NsenterMounter) MakeRShared(path string) error

                                                          func (*NsenterMounter) Mount

                                                          func (n *NsenterMounter) Mount(source string, target string, fstype string, options []string) error

                                                            Mount runs mount(8) in the host's root mount namespace. Aside from this aspect, Mount has the same semantics as the mounter returned by mount.New()

                                                            func (*NsenterMounter) PathIsDevice

                                                            func (n *NsenterMounter) PathIsDevice(pathname string) (bool, error)

                                                              PathIsDevice uses FileInfo returned from os.Stat to check if path refers to a device.

                                                              func (*NsenterMounter) Unmount

                                                              func (n *NsenterMounter) Unmount(target string) error

                                                                Unmount runs umount(8) in the host's mount namespace.

                                                                type SafeFormatAndMount

                                                                type SafeFormatAndMount struct {
                                                                	Interface
                                                                	Exec
                                                                }

                                                                  SafeFormatAndMount probes a device to see if it is formatted. Namely it checks to see if a file system is present. If so it mounts it otherwise the device is formatted first then mounted.

                                                                  func (*SafeFormatAndMount) FormatAndMount

                                                                  func (mounter *SafeFormatAndMount) FormatAndMount(source string, target string, fstype string, options []string) error

                                                                    FormatAndMount formats the given disk, if needed, and mounts it. That is if the disk is not formatted and it is not being mounted as read-only it will format it first then mount it. Otherwise, if the disk is already formatted or it is being mounted as read-only, it will be mounted without formatting.

                                                                    func (*SafeFormatAndMount) GetDiskFormat

                                                                    func (mounter *SafeFormatAndMount) GetDiskFormat(disk string) (string, error)

                                                                      GetDiskFormat uses 'blkid' to see if the given disk is unformated

                                                                      type Subpath

                                                                      type Subpath struct {
                                                                      	// index of the VolumeMount for this container
                                                                      	VolumeMountIndex int
                                                                      	// Full path to the subpath directory on the host
                                                                      	Path string
                                                                      	// name of the volume that is a valid directory name.
                                                                      	VolumeName string
                                                                      	// Full path to the volume path
                                                                      	VolumePath string
                                                                      	// Path to the pod's directory, including pod UID
                                                                      	PodDir string
                                                                      	// Name of the container
                                                                      	ContainerName string
                                                                      }