1/* 2 * Copyright (C) 2001 - 2003 Sistina Software (UK) Limited. 3 * Copyright (C) 2004 - 2009 Red Hat, Inc. All rights reserved. 4 * 5 * This file is released under the LGPL. 6 */ 7 8#ifndef _LINUX_DM_IOCTL_V4_H 9#define _LINUX_DM_IOCTL_V4_H 10 11#include <linux/types.h> 12 13#define DM_DIR "mapper" /* Slashes not supported */ 14#define DM_CONTROL_NODE "control" 15#define DM_MAX_TYPE_NAME 16 16#define DM_NAME_LEN 128 17#define DM_UUID_LEN 129 18 19/* 20 * A traditional ioctl interface for the device mapper. 21 * 22 * Each device can have two tables associated with it, an 23 * 'active' table which is the one currently used by io passing 24 * through the device, and an 'inactive' one which is a table 25 * that is being prepared as a replacement for the 'active' one. 26 * 27 * DM_VERSION: 28 * Just get the version information for the ioctl interface. 29 * 30 * DM_REMOVE_ALL: 31 * Remove all dm devices, destroy all tables. Only really used 32 * for debug. 33 * 34 * DM_LIST_DEVICES: 35 * Get a list of all the dm device names. 36 * 37 * DM_DEV_CREATE: 38 * Create a new device, neither the 'active' or 'inactive' table 39 * slots will be filled. The device will be in suspended state 40 * after creation, however any io to the device will get errored 41 * since it will be out-of-bounds. 42 * 43 * DM_DEV_REMOVE: 44 * Remove a device, destroy any tables. 45 * 46 * DM_DEV_RENAME: 47 * Rename a device or set its uuid if none was previously supplied. 48 * 49 * DM_SUSPEND: 50 * This performs both suspend and resume, depending which flag is 51 * passed in. 52 * Suspend: This command will not return until all pending io to 53 * the device has completed. Further io will be deferred until 54 * the device is resumed. 55 * Resume: It is no longer an error to issue this command on an 56 * unsuspended device. If a table is present in the 'inactive' 57 * slot, it will be moved to the active slot, then the old table 58 * from the active slot will be _destroyed_. Finally the device 59 * is resumed. 60 * 61 * DM_DEV_STATUS: 62 * Retrieves the status for the table in the 'active' slot. 63 * 64 * DM_DEV_WAIT: 65 * Wait for a significant event to occur to the device. This 66 * could either be caused by an event triggered by one of the 67 * targets of the table in the 'active' slot, or a table change. 68 * 69 * DM_TABLE_LOAD: 70 * Load a table into the 'inactive' slot for the device. The 71 * device does _not_ need to be suspended prior to this command. 72 * 73 * DM_TABLE_CLEAR: 74 * Destroy any table in the 'inactive' slot (ie. abort). 75 * 76 * DM_TABLE_DEPS: 77 * Return a set of device dependencies for the 'active' table. 78 * 79 * DM_TABLE_STATUS: 80 * Return the targets status for the 'active' table. 81 * 82 * DM_TARGET_MSG: 83 * Pass a message string to the target at a specific offset of a device. 84 * 85 * DM_DEV_SET_GEOMETRY: 86 * Set the geometry of a device by passing in a string in this format: 87 * 88 * "cylinders heads sectors_per_track start_sector" 89 * 90 * Beware that CHS geometry is nearly obsolete and only provided 91 * for compatibility with dm devices that can be booted by a PC 92 * BIOS. See struct hd_geometry for range limits. Also note that 93 * the geometry is erased if the device size changes. 94 */ 95 96/* 97 * All ioctl arguments consist of a single chunk of memory, with 98 * this structure at the start. If a uuid is specified any 99 * lookup (eg. for a DM_INFO) will be done on that, *not* the 100 * name. 101 */ 102struct dm_ioctl { 103 /* 104 * The version number is made up of three parts: 105 * major - no backward or forward compatibility, 106 * minor - only backwards compatible, 107 * patch - both backwards and forwards compatible. 108 * 109 * All clients of the ioctl interface should fill in the 110 * version number of the interface that they were 111 * compiled with. 112 * 113 * All recognised ioctl commands (ie. those that don't 114 * return -ENOTTY) fill out this field, even if the 115 * command failed. 116 */ 117 __u32 version[3]; /* in/out */ 118 __u32 data_size; /* total size of data passed in 119 * including this struct */ 120 121 __u32 data_start; /* offset to start of data 122 * relative to start of this struct */ 123 124 __u32 target_count; /* in/out */ 125 __s32 open_count; /* out */ 126 __u32 flags; /* in/out */ 127 128 /* 129 * event_nr holds either the event number (input and output) or the 130 * udev cookie value (input only). 131 * The DM_DEV_WAIT ioctl takes an event number as input. 132 * The DM_SUSPEND, DM_DEV_REMOVE and DM_DEV_RENAME ioctls 133 * use the field as a cookie to return in the DM_COOKIE 134 * variable with the uevents they issue. 135 * For output, the ioctls return the event number, not the cookie. 136 */ 137 __u32 event_nr; /* in/out */ 138 __u32 padding; 139 140 __u64 dev; /* in/out */ 141 142 char name[DM_NAME_LEN]; /* device name */ 143 char uuid[DM_UUID_LEN]; /* unique identifier for 144 * the block device */ 145 char data[7]; /* padding or data */ 146}; 147 148/* 149 * Used to specify tables. These structures appear after the 150 * dm_ioctl. 151 */ 152struct dm_target_spec { 153 __u64 sector_start; 154 __u64 length; 155 __s32 status; /* used when reading from kernel only */ 156 157 /* 158 * Location of the next dm_target_spec. 159 * - When specifying targets on a DM_TABLE_LOAD command, this value is 160 * the number of bytes from the start of the "current" dm_target_spec 161 * to the start of the "next" dm_target_spec. 162 * - When retrieving targets on a DM_TABLE_STATUS command, this value 163 * is the number of bytes from the start of the first dm_target_spec 164 * (that follows the dm_ioctl struct) to the start of the "next" 165 * dm_target_spec. 166 */ 167 __u32 next; 168 169 char target_type[DM_MAX_TYPE_NAME]; 170 171 /* 172 * Parameter string starts immediately after this object. 173 * Be careful to add padding after string to ensure correct 174 * alignment of subsequent dm_target_spec. 175 */ 176}; 177 178/* 179 * Used to retrieve the target dependencies. 180 */ 181struct dm_target_deps { 182 __u32 count; /* Array size */ 183 __u32 padding; /* unused */ 184 __u64 dev[0]; /* out */ 185}; 186 187/* 188 * Used to get a list of all dm devices. 189 */ 190struct dm_name_list { 191 __u64 dev; 192 __u32 next; /* offset to the next record from 193 the _start_ of this */ 194 char name[0]; 195}; 196 197/* 198 * Used to retrieve the target versions 199 */ 200struct dm_target_versions { 201 __u32 next; 202 __u32 version[3]; 203 204 char name[0]; 205}; 206 207/* 208 * Used to pass message to a target 209 */ 210struct dm_target_msg { 211 __u64 sector; /* Device sector */ 212 213 char message[0]; 214}; 215 216/* 217 * If you change this make sure you make the corresponding change 218 * to dm-ioctl.c:lookup_ioctl() 219 */ 220enum { 221 /* Top level cmds */ 222 DM_VERSION_CMD = 0, 223 DM_REMOVE_ALL_CMD, 224 DM_LIST_DEVICES_CMD, 225 226 /* device level cmds */ 227 DM_DEV_CREATE_CMD, 228 DM_DEV_REMOVE_CMD, 229 DM_DEV_RENAME_CMD, 230 DM_DEV_SUSPEND_CMD, 231 DM_DEV_STATUS_CMD, 232 DM_DEV_WAIT_CMD, 233 234 /* Table level cmds */ 235 DM_TABLE_LOAD_CMD, 236 DM_TABLE_CLEAR_CMD, 237 DM_TABLE_DEPS_CMD, 238 DM_TABLE_STATUS_CMD, 239 240 /* Added later */ 241 DM_LIST_VERSIONS_CMD, 242 DM_TARGET_MSG_CMD, 243 DM_DEV_SET_GEOMETRY_CMD 244}; 245 246#define DM_IOCTL 0xfd 247 248#define DM_VERSION _IOWR(DM_IOCTL, DM_VERSION_CMD, struct dm_ioctl) 249#define DM_REMOVE_ALL _IOWR(DM_IOCTL, DM_REMOVE_ALL_CMD, struct dm_ioctl) 250#define DM_LIST_DEVICES _IOWR(DM_IOCTL, DM_LIST_DEVICES_CMD, struct dm_ioctl) 251 252#define DM_DEV_CREATE _IOWR(DM_IOCTL, DM_DEV_CREATE_CMD, struct dm_ioctl) 253#define DM_DEV_REMOVE _IOWR(DM_IOCTL, DM_DEV_REMOVE_CMD, struct dm_ioctl) 254#define DM_DEV_RENAME _IOWR(DM_IOCTL, DM_DEV_RENAME_CMD, struct dm_ioctl) 255#define DM_DEV_SUSPEND _IOWR(DM_IOCTL, DM_DEV_SUSPEND_CMD, struct dm_ioctl) 256#define DM_DEV_STATUS _IOWR(DM_IOCTL, DM_DEV_STATUS_CMD, struct dm_ioctl) 257#define DM_DEV_WAIT _IOWR(DM_IOCTL, DM_DEV_WAIT_CMD, struct dm_ioctl) 258 259#define DM_TABLE_LOAD _IOWR(DM_IOCTL, DM_TABLE_LOAD_CMD, struct dm_ioctl) 260#define DM_TABLE_CLEAR _IOWR(DM_IOCTL, DM_TABLE_CLEAR_CMD, struct dm_ioctl) 261#define DM_TABLE_DEPS _IOWR(DM_IOCTL, DM_TABLE_DEPS_CMD, struct dm_ioctl) 262#define DM_TABLE_STATUS _IOWR(DM_IOCTL, DM_TABLE_STATUS_CMD, struct dm_ioctl) 263 264#define DM_LIST_VERSIONS _IOWR(DM_IOCTL, DM_LIST_VERSIONS_CMD, struct dm_ioctl) 265 266#define DM_TARGET_MSG _IOWR(DM_IOCTL, DM_TARGET_MSG_CMD, struct dm_ioctl) 267#define DM_DEV_SET_GEOMETRY _IOWR(DM_IOCTL, DM_DEV_SET_GEOMETRY_CMD, struct dm_ioctl) 268 269#define DM_VERSION_MAJOR 4 270#define DM_VERSION_MINOR 27 271#define DM_VERSION_PATCHLEVEL 0 272#define DM_VERSION_EXTRA "-ioctl (2013-10-30)" 273 274/* Status bits */ 275#define DM_READONLY_FLAG (1 << 0) /* In/Out */ 276#define DM_SUSPEND_FLAG (1 << 1) /* In/Out */ 277#define DM_PERSISTENT_DEV_FLAG (1 << 3) /* In */ 278 279/* 280 * Flag passed into ioctl STATUS command to get table information 281 * rather than current status. 282 */ 283#define DM_STATUS_TABLE_FLAG (1 << 4) /* In */ 284 285/* 286 * Flags that indicate whether a table is present in either of 287 * the two table slots that a device has. 288 */ 289#define DM_ACTIVE_PRESENT_FLAG (1 << 5) /* Out */ 290#define DM_INACTIVE_PRESENT_FLAG (1 << 6) /* Out */ 291 292/* 293 * Indicates that the buffer passed in wasn't big enough for the 294 * results. 295 */ 296#define DM_BUFFER_FULL_FLAG (1 << 8) /* Out */ 297 298/* 299 * This flag is now ignored. 300 */ 301#define DM_SKIP_BDGET_FLAG (1 << 9) /* In */ 302 303/* 304 * Set this to avoid attempting to freeze any filesystem when suspending. 305 */ 306#define DM_SKIP_LOCKFS_FLAG (1 << 10) /* In */ 307 308/* 309 * Set this to suspend without flushing queued ios. 310 * Also disables flushing uncommitted changes in the thin target before 311 * generating statistics for DM_TABLE_STATUS and DM_DEV_WAIT. 312 */ 313#define DM_NOFLUSH_FLAG (1 << 11) /* In */ 314 315/* 316 * If set, any table information returned will relate to the inactive 317 * table instead of the live one. Always check DM_INACTIVE_PRESENT_FLAG 318 * is set before using the data returned. 319 */ 320#define DM_QUERY_INACTIVE_TABLE_FLAG (1 << 12) /* In */ 321 322/* 323 * If set, a uevent was generated for which the caller may need to wait. 324 */ 325#define DM_UEVENT_GENERATED_FLAG (1 << 13) /* Out */ 326 327/* 328 * If set, rename changes the uuid not the name. Only permitted 329 * if no uuid was previously supplied: an existing uuid cannot be changed. 330 */ 331#define DM_UUID_FLAG (1 << 14) /* In */ 332 333/* 334 * If set, all buffers are wiped after use. Use when sending 335 * or requesting sensitive data such as an encryption key. 336 */ 337#define DM_SECURE_DATA_FLAG (1 << 15) /* In */ 338 339/* 340 * If set, a message generated output data. 341 */ 342#define DM_DATA_OUT_FLAG (1 << 16) /* Out */ 343 344/* 345 * If set with DM_DEV_REMOVE or DM_REMOVE_ALL this indicates that if 346 * the device cannot be removed immediately because it is still in use 347 * it should instead be scheduled for removal when it gets closed. 348 * 349 * On return from DM_DEV_REMOVE, DM_DEV_STATUS or other ioctls, this 350 * flag indicates that the device is scheduled to be removed when it 351 * gets closed. 352 */ 353#define DM_DEFERRED_REMOVE (1 << 17) /* In/Out */ 354 355#endif /* _LINUX_DM_IOCTL_H */ 356