1 /* $NetBSD: dm-ioctl.h,v 1.1.1.2 2009/12/02 00:26:09 haad Exp $ */ 2 3 /* 4 * Copyright (C) 2001 - 2003 Sistina Software (UK) Limited. 5 * Copyright (C) 2004 - 2009 Red Hat, Inc. All rights reserved. 6 * 7 * This file is released under the LGPL. 8 */ 9 10 #ifndef _LINUX_DM_IOCTL_V4_H 11 #define _LINUX_DM_IOCTL_V4_H 12 13 #ifdef linux 14 # include <linux/types.h> 15 #endif 16 17 #define DM_DIR "mapper" /* Slashes not supported */ 18 #define DM_MAX_TYPE_NAME 16 19 #define DM_NAME_LEN 128 20 #define DM_UUID_LEN 129 21 22 /* 23 * A traditional ioctl interface for the device mapper. 24 * 25 * Each device can have two tables associated with it, an 26 * 'active' table which is the one currently used by io passing 27 * through the device, and an 'inactive' one which is a table 28 * that is being prepared as a replacement for the 'active' one. 29 * 30 * DM_VERSION: 31 * Just get the version information for the ioctl interface. 32 * 33 * DM_REMOVE_ALL: 34 * Remove all dm devices, destroy all tables. Only really used 35 * for debug. 36 * 37 * DM_LIST_DEVICES: 38 * Get a list of all the dm device names. 39 * 40 * DM_DEV_CREATE: 41 * Create a new device, neither the 'active' or 'inactive' table 42 * slots will be filled. The device will be in suspended state 43 * after creation, however any io to the device will get errored 44 * since it will be out-of-bounds. 45 * 46 * DM_DEV_REMOVE: 47 * Remove a device, destroy any tables. 48 * 49 * DM_DEV_RENAME: 50 * Rename a device. 51 * 52 * DM_SUSPEND: 53 * This performs both suspend and resume, depending which flag is 54 * passed in. 55 * Suspend: This command will not return until all pending io to 56 * the device has completed. Further io will be deferred until 57 * the device is resumed. 58 * Resume: It is no longer an error to issue this command on an 59 * unsuspended device. If a table is present in the 'inactive' 60 * slot, it will be moved to the active slot, then the old table 61 * from the active slot will be _destroyed_. Finally the device 62 * is resumed. 63 * 64 * DM_DEV_STATUS: 65 * Retrieves the status for the table in the 'active' slot. 66 * 67 * DM_DEV_WAIT: 68 * Wait for a significant event to occur to the device. This 69 * could either be caused by an event triggered by one of the 70 * targets of the table in the 'active' slot, or a table change. 71 * 72 * DM_TABLE_LOAD: 73 * Load a table into the 'inactive' slot for the device. The 74 * device does _not_ need to be suspended prior to this command. 75 * 76 * DM_TABLE_CLEAR: 77 * Destroy any table in the 'inactive' slot (ie. abort). 78 * 79 * DM_TABLE_DEPS: 80 * Return a set of device dependencies for the 'active' table. 81 * 82 * DM_TABLE_STATUS: 83 * Return the targets status for the 'active' table. 84 * 85 * DM_TARGET_MSG: 86 * Pass a message string to the target at a specific offset of a device. 87 * 88 * DM_DEV_SET_GEOMETRY: 89 * Set the geometry of a device by passing in a string in this format: 90 * 91 * "cylinders heads sectors_per_track start_sector" 92 * 93 * Beware that CHS geometry is nearly obsolete and only provided 94 * for compatibility with dm devices that can be booted by a PC 95 * BIOS. See struct hd_geometry for range limits. Also note that 96 * the geometry is erased if the device size changes. 97 */ 98 99 /* 100 * All ioctl arguments consist of a single chunk of memory, with 101 * this structure at the start. If a uuid is specified any 102 * lookup (eg. for a DM_INFO) will be done on that, *not* the 103 * name. 104 */ 105 struct dm_ioctl { 106 /* 107 * The version number is made up of three parts: 108 * major - no backward or forward compatibility, 109 * minor - only backwards compatible, 110 * patch - both backwards and forwards compatible. 111 * 112 * All clients of the ioctl interface should fill in the 113 * version number of the interface that they were 114 * compiled with. 115 * 116 * All recognised ioctl commands (ie. those that don't 117 * return -ENOTTY) fill out this field, even if the 118 * command failed. 119 */ 120 uint32_t version[3]; /* in/out */ 121 uint32_t data_size; /* total size of data passed in 122 * including this struct */ 123 124 uint32_t data_start; /* offset to start of data 125 * relative to start of this struct */ 126 127 uint32_t target_count; /* in/out */ 128 int32_t open_count; /* out */ 129 uint32_t flags; /* in/out */ 130 131 /* 132 * event_nr holds either the event number (input and output) or the 133 * udev cookie value (input only). 134 * The DM_DEV_WAIT ioctl takes an event number as input. 135 * The DM_SUSPEND, DM_DEV_REMOVE and DM_DEV_RENAME ioctls 136 * use the field as a cookie to return in the DM_COOKIE 137 * variable with the uevents they issue. 138 * For output, the ioctls return the event number, not the cookie. 139 */ 140 uint32_t event_nr; /* in/out */ 141 uint32_t padding; 142 143 uint64_t dev; /* in/out */ 144 145 char name[DM_NAME_LEN]; /* device name */ 146 char uuid[DM_UUID_LEN]; /* unique identifier for 147 * the block device */ 148 char data[7]; /* padding or data */ 149 }; 150 151 /* 152 * Used to specify tables. These structures appear after the 153 * dm_ioctl. 154 */ 155 struct dm_target_spec { 156 uint64_t sector_start; 157 uint64_t length; 158 int32_t status; /* used when reading from kernel only */ 159 160 /* 161 * Location of the next dm_target_spec. 162 * - When specifying targets on a DM_TABLE_LOAD command, this value is 163 * the number of bytes from the start of the "current" dm_target_spec 164 * to the start of the "next" dm_target_spec. 165 * - When retrieving targets on a DM_TABLE_STATUS command, this value 166 * is the number of bytes from the start of the first dm_target_spec 167 * (that follows the dm_ioctl struct) to the start of the "next" 168 * dm_target_spec. 169 */ 170 uint32_t next; 171 172 char target_type[DM_MAX_TYPE_NAME]; 173 174 /* 175 * Parameter string starts immediately after this object. 176 * Be careful to add padding after string to ensure correct 177 * alignment of subsequent dm_target_spec. 178 */ 179 }; 180 181 /* 182 * Used to retrieve the target dependencies. 183 */ 184 struct dm_target_deps { 185 uint32_t count; /* Array size */ 186 uint32_t padding; /* unused */ 187 uint64_t dev[0]; /* out */ 188 }; 189 190 /* 191 * Used to get a list of all dm devices. 192 */ 193 struct dm_name_list { 194 uint64_t dev; 195 uint32_t next; /* offset to the next record from 196 the _start_ of this */ 197 char name[0]; 198 }; 199 200 /* 201 * Used to retrieve the target versions 202 */ 203 struct dm_target_versions { 204 uint32_t next; 205 uint32_t version[3]; 206 207 char name[0]; 208 }; 209 210 /* 211 * Used to pass message to a target 212 */ 213 struct dm_target_msg { 214 uint64_t sector; /* Device sector */ 215 216 char message[0]; 217 }; 218 219 /* 220 * If you change this make sure you make the corresponding change 221 * to dm-ioctl.c:lookup_ioctl() 222 */ 223 enum { 224 /* Top level cmds */ 225 DM_VERSION_CMD = 0, 226 DM_REMOVE_ALL_CMD, 227 DM_LIST_DEVICES_CMD, 228 229 /* device level cmds */ 230 DM_DEV_CREATE_CMD, 231 DM_DEV_REMOVE_CMD, 232 DM_DEV_RENAME_CMD, 233 DM_DEV_SUSPEND_CMD, 234 DM_DEV_STATUS_CMD, 235 DM_DEV_WAIT_CMD, 236 237 /* Table level cmds */ 238 DM_TABLE_LOAD_CMD, 239 DM_TABLE_CLEAR_CMD, 240 DM_TABLE_DEPS_CMD, 241 DM_TABLE_STATUS_CMD, 242 243 /* Added later */ 244 DM_LIST_VERSIONS_CMD, 245 DM_TARGET_MSG_CMD, 246 DM_DEV_SET_GEOMETRY_CMD 247 }; 248 249 #define DM_IOCTL 0xfd 250 251 #define DM_VERSION _IOWR(DM_IOCTL, DM_VERSION_CMD, struct dm_ioctl) 252 #define DM_REMOVE_ALL _IOWR(DM_IOCTL, DM_REMOVE_ALL_CMD, struct dm_ioctl) 253 #define DM_LIST_DEVICES _IOWR(DM_IOCTL, DM_LIST_DEVICES_CMD, struct dm_ioctl) 254 255 #define DM_DEV_CREATE _IOWR(DM_IOCTL, DM_DEV_CREATE_CMD, struct dm_ioctl) 256 #define DM_DEV_REMOVE _IOWR(DM_IOCTL, DM_DEV_REMOVE_CMD, struct dm_ioctl) 257 #define DM_DEV_RENAME _IOWR(DM_IOCTL, DM_DEV_RENAME_CMD, struct dm_ioctl) 258 #define DM_DEV_SUSPEND _IOWR(DM_IOCTL, DM_DEV_SUSPEND_CMD, struct dm_ioctl) 259 #define DM_DEV_STATUS _IOWR(DM_IOCTL, DM_DEV_STATUS_CMD, struct dm_ioctl) 260 #define DM_DEV_WAIT _IOWR(DM_IOCTL, DM_DEV_WAIT_CMD, struct dm_ioctl) 261 262 #define DM_TABLE_LOAD _IOWR(DM_IOCTL, DM_TABLE_LOAD_CMD, struct dm_ioctl) 263 #define DM_TABLE_CLEAR _IOWR(DM_IOCTL, DM_TABLE_CLEAR_CMD, struct dm_ioctl) 264 #define DM_TABLE_DEPS _IOWR(DM_IOCTL, DM_TABLE_DEPS_CMD, struct dm_ioctl) 265 #define DM_TABLE_STATUS _IOWR(DM_IOCTL, DM_TABLE_STATUS_CMD, struct dm_ioctl) 266 267 #define DM_LIST_VERSIONS _IOWR(DM_IOCTL, DM_LIST_VERSIONS_CMD, struct dm_ioctl) 268 269 #define DM_TARGET_MSG _IOWR(DM_IOCTL, DM_TARGET_MSG_CMD, struct dm_ioctl) 270 #define DM_DEV_SET_GEOMETRY _IOWR(DM_IOCTL, DM_DEV_SET_GEOMETRY_CMD, struct dm_ioctl) 271 272 #define DM_VERSION_MAJOR 4 273 #define DM_VERSION_MINOR 16 274 #define DM_VERSION_PATCHLEVEL 0 275 #define DM_VERSION_EXTRA "-ioctl (2009-11-05)" 276 277 /* Status bits */ 278 #define DM_READONLY_FLAG (1 << 0) /* In/Out */ 279 #define DM_SUSPEND_FLAG (1 << 1) /* In/Out */ 280 #define DM_PERSISTENT_DEV_FLAG (1 << 3) /* In */ 281 282 /* 283 * Flag passed into ioctl STATUS command to get table information 284 * rather than current status. 285 */ 286 #define DM_STATUS_TABLE_FLAG (1 << 4) /* In */ 287 288 /* 289 * Flags that indicate whether a table is present in either of 290 * the two table slots that a device has. 291 */ 292 #define DM_ACTIVE_PRESENT_FLAG (1 << 5) /* Out */ 293 #define DM_INACTIVE_PRESENT_FLAG (1 << 6) /* Out */ 294 295 /* 296 * Indicates that the buffer passed in wasn't big enough for the 297 * results. 298 */ 299 #define DM_BUFFER_FULL_FLAG (1 << 8) /* Out */ 300 301 /* 302 * This flag is now ignored. 303 */ 304 #define DM_SKIP_BDGET_FLAG (1 << 9) /* In */ 305 306 /* 307 * Set this to avoid attempting to freeze any filesystem when suspending. 308 */ 309 #define DM_SKIP_LOCKFS_FLAG (1 << 10) /* In */ 310 311 /* 312 * Set this to suspend without flushing queued ios. 313 */ 314 #define DM_NOFLUSH_FLAG (1 << 11) /* In */ 315 316 /* 317 * If set, any table information returned will relate to the inactive 318 * table instead of the live one. Always check DM_INACTIVE_PRESENT_FLAG 319 * is set before using the data returned. 320 */ 321 #define DM_QUERY_INACTIVE_TABLE_FLAG (1 << 12) /* In */ 322 323 #endif /* _LINUX_DM_IOCTL_H */ 324