| Current File : //usr/include/linux/dm-ioctl.h |
/*
* Copyright (C) 2001 - 2003 Sistina Software (UK) Limited.
* Copyright (C) 2004 - 2009 Red Hat, Inc. All rights reserved.
*
* This file is released under the LGPL.
*/
#ifndef _LINUX_DM_IOCTL_V4_H
#define _LINUX_DM_IOCTL_V4_H
#include <linux/types.h>
#define DM_DIR "mapper" /* Slashes not supported */
#define DM_CONTROL_NODE "control"
#define DM_MAX_TYPE_NAME 16
#define DM_NAME_LEN 128
#define DM_UUID_LEN 129
/*
* A traditional ioctl interface for the device mapper.
*
* Each device can have two tables associated with it, an
* 'active' table which is the one currently used by io passing
* through the device, and an 'inactive' one which is a table
* that is being prepared as a replacement for the 'active' one.
*
* DM_VERSION:
* Just get the version information for the ioctl interface.
*
* DM_REMOVE_ALL:
* Remove all dm devices, destroy all tables. Only really used
* for debug.
*
* DM_LIST_DEVICES:
* Get a list of all the dm device names.
*
* DM_DEV_CREATE:
* Create a new device, neither the 'active' or 'inactive' table
* slots will be filled. The device will be in suspended state
* after creation, however any io to the device will get errored
* since it will be out-of-bounds.
*
* DM_DEV_REMOVE:
* Remove a device, destroy any tables.
*
* DM_DEV_RENAME:
* Rename a device or set its uuid if none was previously supplied.
*
* DM_SUSPEND:
* This performs both suspend and resume, depending which flag is
* passed in.
* Suspend: This command will not return until all pending io to
* the device has completed. Further io will be deferred until
* the device is resumed.
* Resume: It is no longer an error to issue this command on an
* unsuspended device. If a table is present in the 'inactive'
* slot, it will be moved to the active slot, then the old table
* from the active slot will be _destroyed_. Finally the device
* is resumed.
*
* DM_DEV_STATUS:
* Retrieves the status for the table in the 'active' slot.
*
* DM_DEV_WAIT:
* Wait for a significant event to occur to the device. This
* could either be caused by an event triggered by one of the
* targets of the table in the 'active' slot, or a table change.
*
* DM_TABLE_LOAD:
* Load a table into the 'inactive' slot for the device. The
* device does _not_ need to be suspended prior to this command.
*
* DM_TABLE_CLEAR:
* Destroy any table in the 'inactive' slot (ie. abort).
*
* DM_TABLE_DEPS:
* Return a set of device dependencies for the 'active' table.
*
* DM_TABLE_STATUS:
* Return the targets status for the 'active' table.
*
* DM_TARGET_MSG:
* Pass a message string to the target at a specific offset of a device.
*
* DM_DEV_SET_GEOMETRY:
* Set the geometry of a device by passing in a string in this format:
*
* "cylinders heads sectors_per_track start_sector"
*
* Beware that CHS geometry is nearly obsolete and only provided
* for compatibility with dm devices that can be booted by a PC
* BIOS. See struct hd_geometry for range limits. Also note that
* the geometry is erased if the device size changes.
*/
/*
* All ioctl arguments consist of a single chunk of memory, with
* this structure at the start. If a uuid is specified any
* lookup (eg. for a DM_INFO) will be done on that, *not* the
* name.
*/
struct dm_ioctl {
/*
* The version number is made up of three parts:
* major - no backward or forward compatibility,
* minor - only backwards compatible,
* patch - both backwards and forwards compatible.
*
* All clients of the ioctl interface should fill in the
* version number of the interface that they were
* compiled with.
*
* All recognised ioctl commands (ie. those that don't
* return -ENOTTY) fill out this field, even if the
* command failed.
*/
__u32 version[3]; /* in/out */
__u32 data_size; /* total size of data passed in
* including this struct */
__u32 data_start; /* offset to start of data
* relative to start of this struct */
__u32 target_count; /* in/out */
__s32 open_count; /* out */
__u32 flags; /* in/out */
/*
* event_nr holds either the event number (input and output) or the
* udev cookie value (input only).
* The DM_DEV_WAIT ioctl takes an event number as input.
* The DM_SUSPEND, DM_DEV_REMOVE and DM_DEV_RENAME ioctls
* use the field as a cookie to return in the DM_COOKIE
* variable with the uevents they issue.
* For output, the ioctls return the event number, not the cookie.
*/
__u32 event_nr; /* in/out */
__u32 padding;
__u64 dev; /* in/out */
char name[DM_NAME_LEN]; /* device name */
char uuid[DM_UUID_LEN]; /* unique identifier for
* the block device */
char data[7]; /* padding or data */
};
/*
* Used to specify tables. These structures appear after the
* dm_ioctl.
*/
struct dm_target_spec {
__u64 sector_start;
__u64 length;
__s32 status; /* used when reading from kernel only */
/*
* Location of the next dm_target_spec.
* - When specifying targets on a DM_TABLE_LOAD command, this value is
* the number of bytes from the start of the "current" dm_target_spec
* to the start of the "next" dm_target_spec.
* - When retrieving targets on a DM_TABLE_STATUS command, this value
* is the number of bytes from the start of the first dm_target_spec
* (that follows the dm_ioctl struct) to the start of the "next"
* dm_target_spec.
*/
__u32 next;
char target_type[DM_MAX_TYPE_NAME];
/*
* Parameter string starts immediately after this object.
* Be careful to add padding after string to ensure correct
* alignment of subsequent dm_target_spec.
*/
};
/*
* Used to retrieve the target dependencies.
*/
struct dm_target_deps {
__u32 count; /* Array size */
__u32 padding; /* unused */
__u64 dev[0]; /* out */
};
/*
* Used to get a list of all dm devices.
*/
struct dm_name_list {
__u64 dev;
__u32 next; /* offset to the next record from
the _start_ of this */
char name[0];
};
/*
* Used to retrieve the target versions
*/
struct dm_target_versions {
__u32 next;
__u32 version[3];
char name[0];
};
/*
* Used to pass message to a target
*/
struct dm_target_msg {
__u64 sector; /* Device sector */
char message[0];
};
/*
* If you change this make sure you make the corresponding change
* to dm-ioctl.c:lookup_ioctl()
*/
enum {
/* Top level cmds */
DM_VERSION_CMD = 0,
DM_REMOVE_ALL_CMD,
DM_LIST_DEVICES_CMD,
/* device level cmds */
DM_DEV_CREATE_CMD,
DM_DEV_REMOVE_CMD,
DM_DEV_RENAME_CMD,
DM_DEV_SUSPEND_CMD,
DM_DEV_STATUS_CMD,
DM_DEV_WAIT_CMD,
/* Table level cmds */
DM_TABLE_LOAD_CMD,
DM_TABLE_CLEAR_CMD,
DM_TABLE_DEPS_CMD,
DM_TABLE_STATUS_CMD,
/* Added later */
DM_LIST_VERSIONS_CMD,
DM_TARGET_MSG_CMD,
DM_DEV_SET_GEOMETRY_CMD,
DM_DEV_ARM_POLL_CMD,
};
#define DM_IOCTL 0xfd
#define DM_VERSION _IOWR(DM_IOCTL, DM_VERSION_CMD, struct dm_ioctl)
#define DM_REMOVE_ALL _IOWR(DM_IOCTL, DM_REMOVE_ALL_CMD, struct dm_ioctl)
#define DM_LIST_DEVICES _IOWR(DM_IOCTL, DM_LIST_DEVICES_CMD, struct dm_ioctl)
#define DM_DEV_CREATE _IOWR(DM_IOCTL, DM_DEV_CREATE_CMD, struct dm_ioctl)
#define DM_DEV_REMOVE _IOWR(DM_IOCTL, DM_DEV_REMOVE_CMD, struct dm_ioctl)
#define DM_DEV_RENAME _IOWR(DM_IOCTL, DM_DEV_RENAME_CMD, struct dm_ioctl)
#define DM_DEV_SUSPEND _IOWR(DM_IOCTL, DM_DEV_SUSPEND_CMD, struct dm_ioctl)
#define DM_DEV_STATUS _IOWR(DM_IOCTL, DM_DEV_STATUS_CMD, struct dm_ioctl)
#define DM_DEV_WAIT _IOWR(DM_IOCTL, DM_DEV_WAIT_CMD, struct dm_ioctl)
#define DM_DEV_ARM_POLL _IOWR(DM_IOCTL, DM_DEV_ARM_POLL_CMD, struct dm_ioctl)
#define DM_TABLE_LOAD _IOWR(DM_IOCTL, DM_TABLE_LOAD_CMD, struct dm_ioctl)
#define DM_TABLE_CLEAR _IOWR(DM_IOCTL, DM_TABLE_CLEAR_CMD, struct dm_ioctl)
#define DM_TABLE_DEPS _IOWR(DM_IOCTL, DM_TABLE_DEPS_CMD, struct dm_ioctl)
#define DM_TABLE_STATUS _IOWR(DM_IOCTL, DM_TABLE_STATUS_CMD, struct dm_ioctl)
#define DM_LIST_VERSIONS _IOWR(DM_IOCTL, DM_LIST_VERSIONS_CMD, struct dm_ioctl)
#define DM_TARGET_MSG _IOWR(DM_IOCTL, DM_TARGET_MSG_CMD, struct dm_ioctl)
#define DM_DEV_SET_GEOMETRY _IOWR(DM_IOCTL, DM_DEV_SET_GEOMETRY_CMD, struct dm_ioctl)
#define DM_VERSION_MAJOR 4
#define DM_VERSION_MINOR 37
#define DM_VERSION_PATCHLEVEL 1
#define DM_VERSION_EXTRA "-ioctl (2018-04-03)"
/* Status bits */
#define DM_READONLY_FLAG (1 << 0) /* In/Out */
#define DM_SUSPEND_FLAG (1 << 1) /* In/Out */
#define DM_PERSISTENT_DEV_FLAG (1 << 3) /* In */
/*
* Flag passed into ioctl STATUS command to get table information
* rather than current status.
*/
#define DM_STATUS_TABLE_FLAG (1 << 4) /* In */
/*
* Flags that indicate whether a table is present in either of
* the two table slots that a device has.
*/
#define DM_ACTIVE_PRESENT_FLAG (1 << 5) /* Out */
#define DM_INACTIVE_PRESENT_FLAG (1 << 6) /* Out */
/*
* Indicates that the buffer passed in wasn't big enough for the
* results.
*/
#define DM_BUFFER_FULL_FLAG (1 << 8) /* Out */
/*
* This flag is now ignored.
*/
#define DM_SKIP_BDGET_FLAG (1 << 9) /* In */
/*
* Set this to avoid attempting to freeze any filesystem when suspending.
*/
#define DM_SKIP_LOCKFS_FLAG (1 << 10) /* In */
/*
* Set this to suspend without flushing queued ios.
* Also disables flushing uncommitted changes in the thin target before
* generating statistics for DM_TABLE_STATUS and DM_DEV_WAIT.
*/
#define DM_NOFLUSH_FLAG (1 << 11) /* In */
/*
* If set, any table information returned will relate to the inactive
* table instead of the live one. Always check DM_INACTIVE_PRESENT_FLAG
* is set before using the data returned.
*/
#define DM_QUERY_INACTIVE_TABLE_FLAG (1 << 12) /* In */
/*
* If set, a uevent was generated for which the caller may need to wait.
*/
#define DM_UEVENT_GENERATED_FLAG (1 << 13) /* Out */
/*
* If set, rename changes the uuid not the name. Only permitted
* if no uuid was previously supplied: an existing uuid cannot be changed.
*/
#define DM_UUID_FLAG (1 << 14) /* In */
/*
* If set, all buffers are wiped after use. Use when sending
* or requesting sensitive data such as an encryption key.
*/
#define DM_SECURE_DATA_FLAG (1 << 15) /* In */
/*
* If set, a message generated output data.
*/
#define DM_DATA_OUT_FLAG (1 << 16) /* Out */
/*
* If set with DM_DEV_REMOVE or DM_REMOVE_ALL this indicates that if
* the device cannot be removed immediately because it is still in use
* it should instead be scheduled for removal when it gets closed.
*
* On return from DM_DEV_REMOVE, DM_DEV_STATUS or other ioctls, this
* flag indicates that the device is scheduled to be removed when it
* gets closed.
*/
#define DM_DEFERRED_REMOVE (1 << 17) /* In/Out */
/*
* If set, the device is suspended internally.
*/
#define DM_INTERNAL_SUSPEND_FLAG (1 << 18) /* Out */
#endif /* _LINUX_DM_IOCTL_H */