Struct devicemapper::ThinPoolDev

pub struct ThinPoolDev { /* fields omitted */ }

DM construct to contain thin provisioned devices

Methods

impl ThinPoolDev

Use DM to create a "thin-pool". A "thin-pool" is shared space for other thin provisioned devices to use.

See section "Setting up a fresh pool device": https://www.kernel.org/doc/Documentation/device-mapper/thin-provisioning.txt

fn new(
    dm: &DM,
    name: &DmName,
    uuid: Option<&DmUuid>,
    meta: LinearDev,
    data: LinearDev,
    data_block_size: Sectors,
    low_water_mark: DataBlocks
) -> DmResult<ThinPoolDev>

Construct a new ThinPoolDev with the given data and meta devs. Returns an error if the device is already known to the kernel. Returns an error if data_block_size is not within required range. Precondition: the metadata device does not contain any pool metadata.

fn meta_dev(&self) -> &LinearDev

Obtain the meta device that backs this thin pool device.

fn data_dev(&self) -> &LinearDev

Obtain the data device that backs this thin pool device.

fn data_block_size(&self) -> Sectors

Obtain the data block size for this thin pool device.

fn setup(
    dm: &DM,
    name: &DmName,
    uuid: Option<&DmUuid>,
    meta: LinearDev,
    data: LinearDev,
    data_block_size: Sectors,
    low_water_mark: DataBlocks
) -> DmResult<ThinPoolDev>

Set up a thin pool from the given metadata and data device. Returns an error if data_block_size is not within required range. Precondition: There is existing metadata for this thinpool device on the metadata device. If the metadata is corrupted, subsequent errors will result, so it is expected that the metadata is well-formed and consistent with the data on the data device.

fn status(&self, dm: &DM) -> DmResult<ThinPoolStatus>

Get the current status of the thinpool. Returns an error if there was an error getting the status value. Panics if there is an error parsing the status value. Note: Kernel docs show the ordering of the discard_passdown and the summary field opposite to the code below. But this code couldn't pass tests unless it were correct and the kernel docs wrong.

fn set_meta_table(
    &mut self,
    dm: &DM,
    table: Vec<TargetLine<LinearDevTargetParams>>
) -> DmResult<()>

Set the table for the existing metadata device. Warning: It is the client's responsibility to make sure the designated table is compatible with the device's existing table. If are not, this function will still succeed, but some kind of data corruption will be the inevitable result.

fn set_data_table(
    &mut self,
    dm: &DM,
    table: Vec<TargetLine<LinearDevTargetParams>>
) -> DmResult<()>

Set the data device's existing table. Warning: It is the client's responsibility to make sure the designated table is compatible with the device's existing table. If not, this function will still succeed, but some kind of data corruption will be the inevitable result.

Trait Implementations

impl Debug for ThinPoolDev

fn fmt(&self, __arg_0: &mut Formatter) -> Result

Formats the value using the given formatter.

impl DmDevice<ThinPoolDevTargetTable> for ThinPoolDev

fn device(&self) -> Device

The device.

fn devnode(&self) -> PathBuf

The device's device node.

fn equivalent_tables(
    left: &ThinPoolDevTargetTable,
    right: &ThinPoolDevTargetTable
) -> DmResult<bool>

Check if tables indicate an equivalent device.

fn name(&self) -> &DmName

The device's name.

fn size(&self) -> Sectors

The number of sectors available for user data.

fn table(&self) -> &ThinPoolDevTargetTable

What the device thinks its table is.

fn teardown(self, dm: &DM) -> DmResult<()>

Erase the kernel's memory of this device.

fn uuid(&self) -> Option<&DmUuid>

The device's UUID, if available. Note that the UUID is not any standard UUID format.

fn load_table(dm: &DM, id: &DevId) -> DmResult<T>

The devicemapper table