external/gpl2/lvm2/dist/include/dm-ioctl.h

   1 /*      $NetBSD: dm-ioctl.h,v 1.4 2009/12/02 00:58:02 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        6
 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 */