mount

Documentation

Overview

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
• func GetDeviceNameFromMount(mounter Interface, mountPath string) (string, int, error)
• func GetMountRefs(mounter Interface, mountPath string) ([]string, error)
• func IsNotMountPoint(file string) (bool, error)
• func PathExists(path string) (bool, error)
• func UnmountPath(mountPath string, mounter Interface) error
• type Interface
  • func New(mounterPath string) Interface
• type MountPoint
• type Mounter
  • func (mounter *Mounter) DeviceOpened(pathname string) (bool, error)
  • func (mounter *Mounter) GetDeviceNameFromMount(mountPath, pluginDir string) (string, error)
  • func (mounter *Mounter) IsLikelyNotMountPoint(file string) (bool, error)
  • func (*Mounter) List() ([]MountPoint, error)
  • func (mounter *Mounter) Mount(source string, target string, fstype string, options []string) error
  • func (mounter *Mounter) PathIsDevice(pathname string) (bool, error)
  • func (mounter *Mounter) Unmount(target string) error
• type SafeFormatAndMount
  • func (mounter *SafeFormatAndMount) FormatAndMount(source string, target string, fstype string, options []string) error

Constants

const (
	MountsInGlobalPDPath = "mounts"
)

Functions

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 GetMountRefs

func GetMountRefs(mounter Interface, mountPath string) ([]string, error)

GetMountRefs finds all other references to the device referenced by mountPath; returns a list of paths.

func IsNotMountPoint

func IsNotMountPoint(file string) (bool, error)

func PathExists

func PathExists(path string) (bool, error)

PathExists returns true if the specified path exists.

func UnmountPath

func UnmountPath(mountPath string, mounter Interface) error

UnmountPath is a common unmount routine that unmounts the given path and deletes the remaining directory if successful.

Types

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)
	// IsLikelyNotMountPoint determines if a directory is a mountpoint.
	// It should return ErrNotExist when the directory does not exist.
	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)
}

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.

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) 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) 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) List

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

List returns a list of all mounted filesystems.

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 emtpy string in case it's not required, e.g. for remount, or for auto filesystem type, where kernel handles fs type 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 SafeFormatAndMount

type SafeFormatAndMount struct {
	Interface
	Runner exec.Interface
}

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.