include/linux/dm-ioctl.h

   1 /*
   2  * Copyright (C) 2001 - 2003 Sistina Software (UK) Limited.
   3  *
   4  * This file is released under the LGPL.
   5  */
   6
   7 #ifndef _LINUX_DM_IOCTL_V4_H
   8 #define _LINUX_DM_IOCTL_V4_H
   9
  10 #include <linux/types.h>
  11
  12 #define DM_DIR "mapper"         /* Slashes not supported */
  13 #define DM_MAX_TYPE_NAME 16
  14 #define DM_NAME_LEN 128
  15 #define DM_UUID_LEN 129
  16
  17 /*
  18  * A traditional ioctl interface for the device mapper.
  19  *
  20  * Each device can have two tables associated with it, an
  21  * 'active' table which is the one currently used by io passing
  22  * through the device, and an 'inactive' one which is a table
  23  * that is being prepared as a replacement for the 'active' one.
  24  *
  25  * DM_VERSION:
  26  * Just get the version information for the ioctl interface.
  27  *
  28  * DM_REMOVE_ALL:
  29  * Remove all dm devices, destroy all tables.  Only really used
  30  * for debug.
  31  *
  32  * DM_LIST_DEVICES:
  33  * Get a list of all the dm device names.
  34  *
  35  * DM_DEV_CREATE:
  36  * Create a new device, neither the 'active' or 'inactive' table
  37  * slots will be filled.  The device will be in suspended state
  38  * after creation, however any io to the device will get errored
  39  * since it will be out-of-bounds.
  40  *
  41  * DM_DEV_REMOVE:
  42  * Remove a device, destroy any tables.
  43  *
  44  * DM_DEV_RENAME:
  45  * Rename a device.
  46  *
  47  * DM_SUSPEND:
  48  * This performs both suspend and resume, depending which flag is
  49  * passed in.
  50  * Suspend: This command will not return until all pending io to
  51  * the device has completed.  Further io will be deferred until
  52  * the device is resumed.
  53  * Resume: It is no longer an error to issue this command on an
  54  * unsuspended device.  If a table is present in the 'inactive'
  55  * slot, it will be moved to the active slot, then the old table
  56  * from the active slot will be _destroyed_.  Finally the device
  57  * is resumed.
  58  *
  59  * DM_DEV_STATUS:
  60  * Retrieves the status for the table in the 'active' slot.
  61  *
  62  * DM_DEV_WAIT:
  63  * Wait for a significant event to occur to the device.  This
  64  * could either be caused by an event triggered by one of the
  65  * targets of the table in the 'active' slot, or a table change.
  66  *
  67  * DM_TABLE_LOAD:
  68  * Load a table into the 'inactive' slot for the device.  The
  69  * device does _not_ need to be suspended prior to this command.
  70  *
  71  * DM_TABLE_CLEAR:
  72  * Destroy any table in the 'inactive' slot (ie. abort).
  73  *
  74  * DM_TABLE_DEPS:
  75  * Return a set of device dependencies for the 'active' table.
  76  *
  77  * DM_TABLE_STATUS:
  78  * Return the targets status for the 'active' table.
  79  */
  80
  81 /*
  82  * All ioctl arguments consist of a single chunk of memory, with
  83  * this structure at the start.  If a uuid is specified any
  84  * lookup (eg. for a DM_INFO) will be done on that, *not* the
  85  * name.
  86  */
  87 struct dm_ioctl {
  88         /*
  89          * The version number is made up of three parts:
  90          * major - no backward or forward compatibility,
  91          * minor - only backwards compatible,
  92          * patch - both backwards and forwards compatible.
  93          *
  94          * All clients of the ioctl interface should fill in the
  95          * version number of the interface that they were
  96          * compiled with.
  97          *
  98          * All recognised ioctl commands (ie. those that don't
  99          * return -ENOTTY) fill out this field, even if the
 100          * command failed.
 101          */
 102         uint32_t version[3];    /* in/out */
 103         uint32_t data_size;     /* total size of data passed in
 104                                  * including this struct */
 105
 106         uint32_t data_start;    /* offset to start of data
 107                                  * relative to start of this struct */
 108
 109         uint32_t target_count;  /* in/out */
 110         int32_t open_count;     /* out */
 111         uint32_t flags;         /* in/out */
 112         uint32_t event_nr;              /* in/out */
 113         uint32_t padding;
 114
 115         uint64_t dev;           /* in/out */
 116
 117         char name[DM_NAME_LEN]; /* device name */
 118         char uuid[DM_UUID_LEN]; /* unique identifier for
 119                                  * the block device */
 120 };
 121
 122 /*
 123  * Used to specify tables.  These structures appear after the
 124  * dm_ioctl.
 125  */
 126 struct dm_target_spec {
 127         uint64_t sector_start;
 128         uint64_t length;
 129         int32_t status;         /* used when reading from kernel only */
 130
 131         /*
 132          * Location of the next dm_target_spec.
 133          * - When specifying targets on a DM_TABLE_LOAD command, this value is
 134          *   the number of bytes from the start of the "current" dm_target_spec
 135          *   to the start of the "next" dm_target_spec.
 136          * - When retrieving targets on a DM_TABLE_STATUS command, this value
 137          *   is the number of bytes from the start of the first dm_target_spec
 138          *   (that follows the dm_ioctl struct) to the start of the "next"
 139          *   dm_target_spec.
 140          */
 141         uint32_t next;
 142
 143         char target_type[DM_MAX_TYPE_NAME];
 144
 145         /*
 146          * Parameter string starts immediately after this object.
 147          * Be careful to add padding after string to ensure correct
 148          * alignment of subsequent dm_target_spec.
 149          */
 150 };
 151
 152 /*
 153  * Used to retrieve the target dependencies.
 154  */
 155 struct dm_target_deps {
 156         uint32_t count; /* Array size */
 157         uint32_t padding;       /* unused */
 158         uint64_t dev[0];        /* out */
 159 };
 160
 161 /*
 162  * Used to get a list of all dm devices.
 163  */
 164 struct dm_name_list {
 165         uint64_t dev;
 166         uint32_t next;          /* offset to the next record from
 167                                    the _start_ of this */
 168         char name[0];
 169 };
 170
 171 /*
 172  * Used to retrieve the target versions
 173  */
 174 struct dm_target_versions {
 175         uint32_t next;
 176         uint32_t version[3];
 177
 178         char name[0];
 179 };
 180
 181 /*
 182  * If you change this make sure you make the corresponding change
 183  * to dm-ioctl.c:lookup_ioctl()
 184  */
 185 enum {
 186         /* Top level cmds */
 187         DM_VERSION_CMD = 0,
 188         DM_REMOVE_ALL_CMD,
 189         DM_LIST_DEVICES_CMD,
 190
 191         /* device level cmds */
 192         DM_DEV_CREATE_CMD,
 193         DM_DEV_REMOVE_CMD,
 194         DM_DEV_RENAME_CMD,
 195         DM_DEV_SUSPEND_CMD,
 196         DM_DEV_STATUS_CMD,
 197         DM_DEV_WAIT_CMD,
 198
 199         /* Table level cmds */
 200         DM_TABLE_LOAD_CMD,
 201         DM_TABLE_CLEAR_CMD,
 202         DM_TABLE_DEPS_CMD,
 203         DM_TABLE_STATUS_CMD,
 204
 205         /* Added later */
 206         DM_LIST_VERSIONS_CMD,
 207 };
 208
 209 /*
 210  * The dm_ioctl struct passed into the ioctl is just the header
 211  * on a larger chunk of memory.  On x86-64 and other
 212  * architectures the dm-ioctl struct will be padded to an 8 byte
 213  * boundary so the size will be different, which would change the
 214  * ioctl code - yes I really messed up.  This hack forces these
 215  * architectures to have the correct ioctl code.
 216  */
 217 #ifdef CONFIG_COMPAT
 218 typedef char ioctl_struct[308];
 219 #define DM_VERSION_32       _IOWR(DM_IOCTL, DM_VERSION_CMD, ioctl_struct)
 220 #define DM_REMOVE_ALL_32    _IOWR(DM_IOCTL, DM_REMOVE_ALL_CMD, ioctl_struct)
 221 #define DM_LIST_DEVICES_32  _IOWR(DM_IOCTL, DM_LIST_DEVICES_CMD, ioctl_struct)
 222
 223 #define DM_DEV_CREATE_32    _IOWR(DM_IOCTL, DM_DEV_CREATE_CMD, ioctl_struct)
 224 #define DM_DEV_REMOVE_32    _IOWR(DM_IOCTL, DM_DEV_REMOVE_CMD, ioctl_struct)
 225 #define DM_DEV_RENAME_32    _IOWR(DM_IOCTL, DM_DEV_RENAME_CMD, ioctl_struct)
 226 #define DM_DEV_SUSPEND_32   _IOWR(DM_IOCTL, DM_DEV_SUSPEND_CMD, ioctl_struct)
 227 #define DM_DEV_STATUS_32    _IOWR(DM_IOCTL, DM_DEV_STATUS_CMD, ioctl_struct)
 228 #define DM_DEV_WAIT_32      _IOWR(DM_IOCTL, DM_DEV_WAIT_CMD, ioctl_struct)
 229
 230 #define DM_TABLE_LOAD_32    _IOWR(DM_IOCTL, DM_TABLE_LOAD_CMD, ioctl_struct)
 231 #define DM_TABLE_CLEAR_32   _IOWR(DM_IOCTL, DM_TABLE_CLEAR_CMD, ioctl_struct)
 232 #define DM_TABLE_DEPS_32    _IOWR(DM_IOCTL, DM_TABLE_DEPS_CMD, ioctl_struct)
 233 #define DM_TABLE_STATUS_32  _IOWR(DM_IOCTL, DM_TABLE_STATUS_CMD, ioctl_struct)
 234 #define DM_LIST_VERSIONS_32 _IOWR(DM_IOCTL, DM_LIST_VERSIONS_CMD, ioctl_struct)
 235 #endif
 236
 237 #define DM_IOCTL 0xfd
 238
 239 #define DM_VERSION       _IOWR(DM_IOCTL, DM_VERSION_CMD, struct dm_ioctl)
 240 #define DM_REMOVE_ALL    _IOWR(DM_IOCTL, DM_REMOVE_ALL_CMD, struct dm_ioctl)
 241 #define DM_LIST_DEVICES  _IOWR(DM_IOCTL, DM_LIST_DEVICES_CMD, struct dm_ioctl)
 242
 243 #define DM_DEV_CREATE    _IOWR(DM_IOCTL, DM_DEV_CREATE_CMD, struct dm_ioctl)
 244 #define DM_DEV_REMOVE    _IOWR(DM_IOCTL, DM_DEV_REMOVE_CMD, struct dm_ioctl)
 245 #define DM_DEV_RENAME    _IOWR(DM_IOCTL, DM_DEV_RENAME_CMD, struct dm_ioctl)
 246 #define DM_DEV_SUSPEND   _IOWR(DM_IOCTL, DM_DEV_SUSPEND_CMD, struct dm_ioctl)
 247 #define DM_DEV_STATUS    _IOWR(DM_IOCTL, DM_DEV_STATUS_CMD, struct dm_ioctl)
 248 #define DM_DEV_WAIT      _IOWR(DM_IOCTL, DM_DEV_WAIT_CMD, struct dm_ioctl)
 249
 250 #define DM_TABLE_LOAD    _IOWR(DM_IOCTL, DM_TABLE_LOAD_CMD, struct dm_ioctl)
 251 #define DM_TABLE_CLEAR   _IOWR(DM_IOCTL, DM_TABLE_CLEAR_CMD, struct dm_ioctl)
 252 #define DM_TABLE_DEPS    _IOWR(DM_IOCTL, DM_TABLE_DEPS_CMD, struct dm_ioctl)
 253 #define DM_TABLE_STATUS  _IOWR(DM_IOCTL, DM_TABLE_STATUS_CMD, struct dm_ioctl)
 254
 255 #define DM_LIST_VERSIONS _IOWR(DM_IOCTL, DM_LIST_VERSIONS_CMD, struct dm_ioctl)
 256
 257 #define DM_VERSION_MAJOR        4
 258 #define DM_VERSION_MINOR        1
 259 #define DM_VERSION_PATCHLEVEL   0
 260 #define DM_VERSION_EXTRA        "-ioctl (2003-12-10)"
 261
 262 /* Status bits */
 263 #define DM_READONLY_FLAG        (1 << 0) /* In/Out */
 264 #define DM_SUSPEND_FLAG         (1 << 1) /* In/Out */
 265 #define DM_PERSISTENT_DEV_FLAG  (1 << 3) /* In */
 266
 267 /*
 268  * Flag passed into ioctl STATUS command to get table information
 269  * rather than current status.
 270  */
 271 #define DM_STATUS_TABLE_FLAG    (1 << 4) /* In */
 272
 273 /*
 274  * Flags that indicate whether a table is present in either of
 275  * the two table slots that a device has.
 276  */
 277 #define DM_ACTIVE_PRESENT_FLAG   (1 << 5) /* Out */
 278 #define DM_INACTIVE_PRESENT_FLAG (1 << 6) /* Out */
 279
 280 /*
 281  * Indicates that the buffer passed in wasn't big enough for the
 282  * results.
 283  */
 284 #define DM_BUFFER_FULL_FLAG     (1 << 8) /* Out */
 285
 286 #endif                          /* _LINUX_DM_IOCTL_H */