Documentation
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Overview ¶
Package loop implements an interface to configure Linux loop devices.
This package requires Linux 5.8 or higher because it uses the newer LOOP_CONFIGURE ioctl, which is better-behaved and twice as fast as the old approach. It doesn't support all of the cryptloop functionality as it has been superseded by dm-crypt and has known vulnerabilities. It also doesn't support on-the-fly reconfiguration of loop devices as this is rather unusual, works only under very specific circumstances and would make the API less clean.
Index ¶
Constants ¶
const ( // Makes the loop device read-only even if the backing file is read-write. FlagReadOnly = 1 // Unbinds the backing file as soon as the last user is gone. Useful for // unbinding after unmount. FlagAutoclear = 4 // Enables kernel-side partition scanning on the loop device. Needed if you // want to access specific partitions on a loop device. FlagPartscan = 8 // Enables direct IO for the loop device, bypassing caches and buffer // copying. FlagDirectIO = 16 )
All from @linux//include/uapi/linux:loop.h
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Config ¶
type Config struct {
// Block size of the loop device in bytes. Power of 2 between 512 and page
// size. Zero defaults to an reasonable block size.
BlockSize uint32
// Combination of flags from the Flag constants in this package.
Flags uint32
// Offset in bytes from the start of the file to the first byte of the
// device. Usually zero.
Offset uint64
// Maximum size of the loop device in bytes. Zero defaults to the whole
// file.
SizeLimit uint64
}
type Device ¶
type Device struct {
// contains filtered or unexported fields
}
Device represents a loop device.
func Open ¶
Open opens a loop device at the given path. It returns an error if the path is not a loop device.
func (*Device) BackingFilePath ¶
BackingFilePath returns the path of the backing file
func (*Device) Close ¶
Close closes all file descriptors open to the device. Does not remove the device itself or alter its configuration.
func (*Device) RefreshSize ¶
RefreshSize recalculates the size of the loop device based on the config and the size of the backing file.
Source Files