DeviceMapper: libblockdev Reference Manual for libblockdev 3.1.0.

## DeviceMapper DeviceMapper — plugin for basic operations with device mapper |

## Functions

void | bd_dm_close ()
gboolean | bd_dm_init ()
GQuark | bd_dm_error_quark ()
gboolean | bd_dm_create_linear ()
gboolean | bd_dm_remove ()
gchar * | bd_dm_name_from_node ()
gchar * | bd_dm_node_from_name ()
gboolean | bd_dm_map_exists ()
gchar * | bd_dm_get_subsystem_from_name ()
gboolean | bd_dm_is_tech_avail ()

## Types and Values

#define | BD_DM_ERROR
enum | BDDMError
enum | BDDMTech
enum | BDDMTechMode

## Includes

    #include <dm.h>

## Description

A plugin for basic operations with device mapper.

## Functions

### bd_dm_close ()

    void
    bd_dm_close (void);

Cleans up after the plugin. **This function is called automatically by the library's functions that unload it.**

### bd_dm_init ()

    gboolean
    bd_dm_init (void);

Initializes the plugin. **This function is called automatically by the library's initialization functions.**

### bd_dm_error_quark ()

    GQuark
    bd_dm_error_quark (void);

[skip]

### bd_dm_create_linear ()

    gboolean
    bd_dm_create_linear (const gchar *map_name,
                         const gchar *device,
                         guint64 length,
                         const gchar *uuid,
                         GError **error);

#### Parameters

map_name | name of the map |
device | device to create map for |
length | length of the mapping in sectors |
uuid | UUID for the new dev mapper device or `NULL` if not specified. | [nullable]
error | place to store error (if any). | [out][optional]

#### Returns

whether the new linear mapping `map_name` was successfully created for the `device` or not

Tech category: `BD_DM_TECH_MAP`-`BD_DM_TECH_MODE_CREATE_ACTIVATE`

### bd_dm_remove ()

    gboolean
    bd_dm_remove (const gchar *map_name,
                  GError **error);

#### Parameters

map_name | name of the map to remove |
error | place to store error (if any). | [out][optional]

#### Returns

whether the `map_name` map was successfully removed or not

Tech category: `BD_DM_TECH_MAP`-`BD_DM_TECH_MODE_REMOVE_DEACTIVATE`

### bd_dm_name_from_node ()

    gchar *
    bd_dm_name_from_node (const gchar *dm_node,
                          GError **error);

#### Parameters

dm_node | name of the DM node (e.g. "dm-0") |
error | place to store error (if any). | [out][optional]

#### Returns

map name of the map providing the `dm_node` device or `NULL` (`error` ) contains the error in such cases

Tech category: `BD_DM_TECH_MAP`-`BD_DM_TECH_MODE_QUERY`

### bd_dm_node_from_name ()

    gchar *
    bd_dm_node_from_name (const gchar *map_name,
                          GError **error);

#### Parameters

map_name | name of the queried DM map |
error | place to store error (if any). | [out][optional]

#### Returns

DM node name for the `map_name` map or `NULL` (`error` ) contains the error in such cases

Tech category: `BD_DM_TECH_MAP`-`BD_DM_TECH_MODE_QUERY`

### bd_dm_map_exists ()

    gboolean
    bd_dm_map_exists (const gchar *map_name,
                      gboolean live_only,
                      gboolean active_only,
                      GError **error);

#### Parameters

map_name | name of the queried map |
live_only | whether to go through the live maps only or not |
active_only | whether to ignore suspended maps or not |
error | place to store error (if any). | [out][optional]

#### Returns

whether the given `map_name` exists (and is live if `live_only` is `TRUE` (and is active if `active_only` is `TRUE`)).

Tech category: `BD_DM_TECH_MAP`-`BD_DM_TECH_MODE_QUERY`

### bd_dm_get_subsystem_from_name ()

    gchar *
    bd_dm_get_subsystem_from_name (const gchar *device_name,
                                   GError **error);

#### Parameters

device_name | name of the device |
error | place to store error (if any). | [out][optional]

#### Returns

subsystem of the given device

Tech category: `BD_DM_TECH_MAP`-`BD_DM_TECH_MODE_QUERY`

### bd_dm_is_tech_avail ()

    gboolean
    bd_dm_is_tech_avail (BDDMTech tech,
                         guint64 mode,
                         GError **error);

#### Parameters

tech | the queried tech |
mode | a bit mask of queried modes of operation (BDDMTechMode) for `tech` |
error | place to store error (details about why the `tech` -`mode` combination is not available). | [out][optional]

#### Returns

whether the `tech` -`mode` combination is available -- supported by the plugin implementation and having all the runtime dependencies available

## Types and Values

### BD_DM_ERROR

    #define             BD_DM_ERROR

### enum BDDMError

#### Members

BD_DM_ERROR_TECH_UNAVAIL |  |
BD_DM_ERROR_SYS |  |
BD_DM_ERROR_NOT_ROOT |  |
BD_DM_ERROR_TASK |  |
BD_DM_ERROR_RAID_FAIL |  |
BD_DM_ERROR_RAID_NO_DEVS |  |
BD_DM_ERROR_RAID_NO_EXIST |  |

### enum BDDMTech

#### Members

BD_DM_TECH_MAP |  |

### enum BDDMTechMode

#### Members

BD_DM_TECH_MODE_CREATE_ACTIVATE |  |
BD_DM_TECH_MODE_REMOVE_DEACTIVATE |  |
BD_DM_TECH_MODE_QUERY |  |