diff options
Diffstat (limited to 'src/shared/linux/dm-ioctl.h')
| -rw-r--r-- | src/shared/linux/dm-ioctl.h | 385 |
1 files changed, 385 insertions, 0 deletions
diff --git a/src/shared/linux/dm-ioctl.h b/src/shared/linux/dm-ioctl.h new file mode 100644 index 0000000..19a64fc --- /dev/null +++ b/src/shared/linux/dm-ioctl.h @@ -0,0 +1,385 @@ +/* SPDX-License-Identifier: LGPL-2.0+ WITH Linux-syscall-note */ +/* + * 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[]; /* 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[]; + + /* + * The following members can be accessed by taking a pointer that + * points immediately after the terminating zero character in "name" + * and aligning this pointer to next 8-byte boundary. + * Uuid is present if the flag DM_NAME_LIST_FLAG_HAS_UUID is set. + * + * __u32 event_nr; + * __u32 flags; + * char uuid[0]; + */ +}; + +#define DM_NAME_LIST_FLAG_HAS_UUID 1 +#define DM_NAME_LIST_FLAG_DOESNT_HAVE_UUID 2 + +/* + * Used to retrieve the target versions + */ +struct dm_target_versions { + __u32 next; + __u32 version[3]; + + char name[]; +}; + +/* + * Used to pass message to a target + */ +struct dm_target_msg { + __u64 sector; /* Device sector */ + + char message[]; +}; + +/* + * 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, + DM_GET_TARGET_VERSION_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_GET_TARGET_VERSION _IOWR(DM_IOCTL, DM_GET_TARGET_VERSION_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 27 +#define DM_VERSION_PATCHLEVEL 0 +#define DM_VERSION_EXTRA "-ioctl (2022-02-22)" + +/* 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 */ + +/* + * If set, returns in the in buffer passed by UM, the raw table information + * that would be measured by IMA subsystem on device state change. + */ +#define DM_IMA_MEASUREMENT_FLAG (1 << 19) /* In */ + +#endif /* _LINUX_DM_IOCTL_H */ |