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1/* SPDX-License-Identifier: LGPL-2.0+ WITH Linux-syscall-note */2/*3 * Copyright (C) 2001 - 2003 Sistina Software (UK) Limited.4 * Copyright (C) 2004 - 2009 Red Hat, Inc. All rights reserved.5 *6 * This file is released under the LGPL.7 */8 9#ifndef _LINUX_DM_IOCTL_V4_H10#define _LINUX_DM_IOCTL_V4_H11 12#include <linux/types.h>13 14#define DM_DIR "mapper" /* Slashes not supported */15#define DM_CONTROL_NODE "control"16#define DM_MAX_TYPE_NAME 1617#define DM_NAME_LEN 12818#define DM_UUID_LEN 12919 20/*21 * A traditional ioctl interface for the device mapper.22 *23 * Each device can have two tables associated with it, an24 * 'active' table which is the one currently used by io passing25 * through the device, and an 'inactive' one which is a table26 * that is being prepared as a replacement for the 'active' one.27 *28 * DM_VERSION:29 * Just get the version information for the ioctl interface.30 *31 * DM_REMOVE_ALL:32 * Remove all dm devices, destroy all tables. Only really used33 * for debug.34 *35 * DM_LIST_DEVICES:36 * Get a list of all the dm device names.37 *38 * DM_DEV_CREATE:39 * Create a new device, neither the 'active' or 'inactive' table40 * slots will be filled. The device will be in suspended state41 * after creation, however any io to the device will get errored42 * since it will be out-of-bounds.43 *44 * DM_DEV_REMOVE:45 * Remove a device, destroy any tables.46 *47 * DM_DEV_RENAME:48 * Rename a device or set its uuid if none was previously supplied.49 *50 * DM_SUSPEND:51 * This performs both suspend and resume, depending which flag is52 * passed in.53 * Suspend: This command will not return until all pending io to54 * the device has completed. Further io will be deferred until55 * the device is resumed.56 * Resume: It is no longer an error to issue this command on an57 * unsuspended device. If a table is present in the 'inactive'58 * slot, it will be moved to the active slot, then the old table59 * from the active slot will be _destroyed_. Finally the device60 * is resumed.61 *62 * DM_DEV_STATUS:63 * Retrieves the status for the table in the 'active' slot.64 *65 * DM_DEV_WAIT:66 * Wait for a significant event to occur to the device. This67 * could either be caused by an event triggered by one of the68 * targets of the table in the 'active' slot, or a table change.69 *70 * DM_TABLE_LOAD:71 * Load a table into the 'inactive' slot for the device. The72 * device does _not_ need to be suspended prior to this command.73 *74 * DM_TABLE_CLEAR:75 * Destroy any table in the 'inactive' slot (ie. abort).76 *77 * DM_TABLE_DEPS:78 * Return a set of device dependencies for the 'active' table.79 *80 * DM_TABLE_STATUS:81 * Return the targets status for the 'active' table.82 *83 * DM_TARGET_MSG:84 * Pass a message string to the target at a specific offset of a device.85 *86 * DM_DEV_SET_GEOMETRY:87 * Set the geometry of a device by passing in a string in this format:88 *89 * "cylinders heads sectors_per_track start_sector"90 *91 * Beware that CHS geometry is nearly obsolete and only provided92 * for compatibility with dm devices that can be booted by a PC93 * BIOS. See struct hd_geometry for range limits. Also note that94 * the geometry is erased if the device size changes.95 */96 97/*98 * All ioctl arguments consist of a single chunk of memory, with99 * this structure at the start. If a uuid is specified any100 * lookup (eg. for a DM_INFO) will be done on that, *not* the101 * name.102 */103struct dm_ioctl {104 /*105 * The version number is made up of three parts:106 * major - no backward or forward compatibility,107 * minor - only backwards compatible,108 * patch - both backwards and forwards compatible.109 *110 * All clients of the ioctl interface should fill in the111 * version number of the interface that they were112 * compiled with.113 *114 * All recognised ioctl commands (ie. those that don't115 * return -ENOTTY) fill out this field, even if the116 * command failed.117 */118 __u32 version[3]; /* in/out */119 __u32 data_size; /* total size of data passed in120 * including this struct */121 122 __u32 data_start; /* offset to start of data123 * relative to start of this struct */124 125 __u32 target_count; /* in/out */126 __s32 open_count; /* out */127 __u32 flags; /* in/out */128 129 /*130 * event_nr holds either the event number (input and output) or the131 * udev cookie value (input only).132 * The DM_DEV_WAIT ioctl takes an event number as input.133 * The DM_SUSPEND, DM_DEV_REMOVE and DM_DEV_RENAME ioctls134 * use the field as a cookie to return in the DM_COOKIE135 * variable with the uevents they issue.136 * For output, the ioctls return the event number, not the cookie.137 */138 __u32 event_nr; /* in/out */139 __u32 padding;140 141 __u64 dev; /* in/out */142 143 char name[DM_NAME_LEN]; /* device name */144 char uuid[DM_UUID_LEN]; /* unique identifier for145 * the block device */146 char data[7]; /* padding or data */147};148 149/*150 * Used to specify tables. These structures appear after the151 * dm_ioctl.152 */153struct dm_target_spec {154 __u64 sector_start;155 __u64 length;156 __s32 status; /* used when reading from kernel only */157 158 /*159 * Location of the next dm_target_spec.160 * - When specifying targets on a DM_TABLE_LOAD command, this value is161 * the number of bytes from the start of the "current" dm_target_spec162 * to the start of the "next" dm_target_spec.163 * - When retrieving targets on a DM_TABLE_STATUS command, this value164 * is the number of bytes from the start of the first dm_target_spec165 * (that follows the dm_ioctl struct) to the start of the "next"166 * dm_target_spec.167 */168 __u32 next;169 170 char target_type[DM_MAX_TYPE_NAME];171 172 /*173 * Parameter string starts immediately after this object.174 * Be careful to add padding after string to ensure correct175 * alignment of subsequent dm_target_spec.176 */177};178 179/*180 * Used to retrieve the target dependencies.181 */182struct dm_target_deps {183 __u32 count; /* Array size */184 __u32 padding; /* unused */185 __u64 dev[]; /* out */186};187 188/*189 * Used to get a list of all dm devices.190 */191struct dm_name_list {192 __u64 dev;193 __u32 next; /* offset to the next record from194 the _start_ of this */195 char name[];196 197 /*198 * The following members can be accessed by taking a pointer that199 * points immediately after the terminating zero character in "name"200 * and aligning this pointer to next 8-byte boundary.201 * Uuid is present if the flag DM_NAME_LIST_FLAG_HAS_UUID is set.202 *203 * __u32 event_nr;204 * __u32 flags;205 * char uuid[0];206 */207};208 209#define DM_NAME_LIST_FLAG_HAS_UUID 1210#define DM_NAME_LIST_FLAG_DOESNT_HAVE_UUID 2211 212/*213 * Used to retrieve the target versions214 */215struct dm_target_versions {216 __u32 next;217 __u32 version[3];218 219 char name[];220};221 222/*223 * Used to pass message to a target224 */225struct dm_target_msg {226 __u64 sector; /* Device sector */227 228 char message[];229};230 231/*232 * If you change this make sure you make the corresponding change233 * to dm-ioctl.c:lookup_ioctl()234 */235enum {236 /* Top level cmds */237 DM_VERSION_CMD = 0,238 DM_REMOVE_ALL_CMD,239 DM_LIST_DEVICES_CMD,240 241 /* device level cmds */242 DM_DEV_CREATE_CMD,243 DM_DEV_REMOVE_CMD,244 DM_DEV_RENAME_CMD,245 DM_DEV_SUSPEND_CMD,246 DM_DEV_STATUS_CMD,247 DM_DEV_WAIT_CMD,248 249 /* Table level cmds */250 DM_TABLE_LOAD_CMD,251 DM_TABLE_CLEAR_CMD,252 DM_TABLE_DEPS_CMD,253 DM_TABLE_STATUS_CMD,254 255 /* Added later */256 DM_LIST_VERSIONS_CMD,257 DM_TARGET_MSG_CMD,258 DM_DEV_SET_GEOMETRY_CMD,259 DM_DEV_ARM_POLL_CMD,260 DM_GET_TARGET_VERSION_CMD,261};262 263#define DM_IOCTL 0xfd264 265#define DM_VERSION _IOWR(DM_IOCTL, DM_VERSION_CMD, struct dm_ioctl)266#define DM_REMOVE_ALL _IOWR(DM_IOCTL, DM_REMOVE_ALL_CMD, struct dm_ioctl)267#define DM_LIST_DEVICES _IOWR(DM_IOCTL, DM_LIST_DEVICES_CMD, struct dm_ioctl)268 269#define DM_DEV_CREATE _IOWR(DM_IOCTL, DM_DEV_CREATE_CMD, struct dm_ioctl)270#define DM_DEV_REMOVE _IOWR(DM_IOCTL, DM_DEV_REMOVE_CMD, struct dm_ioctl)271#define DM_DEV_RENAME _IOWR(DM_IOCTL, DM_DEV_RENAME_CMD, struct dm_ioctl)272#define DM_DEV_SUSPEND _IOWR(DM_IOCTL, DM_DEV_SUSPEND_CMD, struct dm_ioctl)273#define DM_DEV_STATUS _IOWR(DM_IOCTL, DM_DEV_STATUS_CMD, struct dm_ioctl)274#define DM_DEV_WAIT _IOWR(DM_IOCTL, DM_DEV_WAIT_CMD, struct dm_ioctl)275#define DM_DEV_ARM_POLL _IOWR(DM_IOCTL, DM_DEV_ARM_POLL_CMD, struct dm_ioctl)276 277#define DM_TABLE_LOAD _IOWR(DM_IOCTL, DM_TABLE_LOAD_CMD, struct dm_ioctl)278#define DM_TABLE_CLEAR _IOWR(DM_IOCTL, DM_TABLE_CLEAR_CMD, struct dm_ioctl)279#define DM_TABLE_DEPS _IOWR(DM_IOCTL, DM_TABLE_DEPS_CMD, struct dm_ioctl)280#define DM_TABLE_STATUS _IOWR(DM_IOCTL, DM_TABLE_STATUS_CMD, struct dm_ioctl)281 282#define DM_LIST_VERSIONS _IOWR(DM_IOCTL, DM_LIST_VERSIONS_CMD, struct dm_ioctl)283#define DM_GET_TARGET_VERSION _IOWR(DM_IOCTL, DM_GET_TARGET_VERSION_CMD, struct dm_ioctl)284 285#define DM_TARGET_MSG _IOWR(DM_IOCTL, DM_TARGET_MSG_CMD, struct dm_ioctl)286#define DM_DEV_SET_GEOMETRY _IOWR(DM_IOCTL, DM_DEV_SET_GEOMETRY_CMD, struct dm_ioctl)287 288#define DM_VERSION_MAJOR 4289#define DM_VERSION_MINOR 48290#define DM_VERSION_PATCHLEVEL 0291#define DM_VERSION_EXTRA "-ioctl (2023-03-01)"292 293/* Status bits */294#define DM_READONLY_FLAG (1 << 0) /* In/Out */295#define DM_SUSPEND_FLAG (1 << 1) /* In/Out */296#define DM_PERSISTENT_DEV_FLAG (1 << 3) /* In */297 298/*299 * Flag passed into ioctl STATUS command to get table information300 * rather than current status.301 */302#define DM_STATUS_TABLE_FLAG (1 << 4) /* In */303 304/*305 * Flags that indicate whether a table is present in either of306 * the two table slots that a device has.307 */308#define DM_ACTIVE_PRESENT_FLAG (1 << 5) /* Out */309#define DM_INACTIVE_PRESENT_FLAG (1 << 6) /* Out */310 311/*312 * Indicates that the buffer passed in wasn't big enough for the313 * results.314 */315#define DM_BUFFER_FULL_FLAG (1 << 8) /* Out */316 317/*318 * This flag is now ignored.319 */320#define DM_SKIP_BDGET_FLAG (1 << 9) /* In */321 322/*323 * Set this to avoid attempting to freeze any filesystem when suspending.324 */325#define DM_SKIP_LOCKFS_FLAG (1 << 10) /* In */326 327/*328 * Set this to suspend without flushing queued ios.329 * Also disables flushing uncommitted changes in the thin target before330 * generating statistics for DM_TABLE_STATUS and DM_DEV_WAIT.331 */332#define DM_NOFLUSH_FLAG (1 << 11) /* In */333 334/*335 * If set, any table information returned will relate to the inactive336 * table instead of the live one. Always check DM_INACTIVE_PRESENT_FLAG337 * is set before using the data returned.338 */339#define DM_QUERY_INACTIVE_TABLE_FLAG (1 << 12) /* In */340 341/*342 * If set, a uevent was generated for which the caller may need to wait.343 */344#define DM_UEVENT_GENERATED_FLAG (1 << 13) /* Out */345 346/*347 * If set, rename changes the uuid not the name. Only permitted348 * if no uuid was previously supplied: an existing uuid cannot be changed.349 */350#define DM_UUID_FLAG (1 << 14) /* In */351 352/*353 * If set, all buffers are wiped after use. Use when sending354 * or requesting sensitive data such as an encryption key.355 */356#define DM_SECURE_DATA_FLAG (1 << 15) /* In */357 358/*359 * If set, a message generated output data.360 */361#define DM_DATA_OUT_FLAG (1 << 16) /* Out */362 363/*364 * If set with DM_DEV_REMOVE or DM_REMOVE_ALL this indicates that if365 * the device cannot be removed immediately because it is still in use366 * it should instead be scheduled for removal when it gets closed.367 *368 * On return from DM_DEV_REMOVE, DM_DEV_STATUS or other ioctls, this369 * flag indicates that the device is scheduled to be removed when it370 * gets closed.371 */372#define DM_DEFERRED_REMOVE (1 << 17) /* In/Out */373 374/*375 * If set, the device is suspended internally.376 */377#define DM_INTERNAL_SUSPEND_FLAG (1 << 18) /* Out */378 379/*380 * If set, returns in the in buffer passed by UM, the raw table information381 * that would be measured by IMA subsystem on device state change.382 */383#define DM_IMA_MEASUREMENT_FLAG (1 << 19) /* In */384 385#endif /* _LINUX_DM_IOCTL_H */386