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      1 /*
      2  * Copyright (C) 2001 - 2003 Sistina Software (UK) Limited.
      3  * Copyright (C) 2004 - 2005 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_MAX_TYPE_NAME 16
     15 #define DM_NAME_LEN 128
     16 #define DM_UUID_LEN 129
     17 
     18 /*
     19  * A traditional ioctl interface for the device mapper.
     20  *
     21  * Each device can have two tables associated with it, an
     22  * 'active' table which is the one currently used by io passing
     23  * through the device, and an 'inactive' one which is a table
     24  * that is being prepared as a replacement for the 'active' one.
     25  *
     26  * DM_VERSION:
     27  * Just get the version information for the ioctl interface.
     28  *
     29  * DM_REMOVE_ALL:
     30  * Remove all dm devices, destroy all tables.  Only really used
     31  * for debug.
     32  *
     33  * DM_LIST_DEVICES:
     34  * Get a list of all the dm device names.
     35  *
     36  * DM_DEV_CREATE:
     37  * Create a new device, neither the 'active' or 'inactive' table
     38  * slots will be filled.  The device will be in suspended state
     39  * after creation, however any io to the device will get errored
     40  * since it will be out-of-bounds.
     41  *
     42  * DM_DEV_REMOVE:
     43  * Remove a device, destroy any tables.
     44  *
     45  * DM_DEV_RENAME:
     46  * Rename a device.
     47  *
     48  * DM_SUSPEND:
     49  * This performs both suspend and resume, depending which flag is
     50  * passed in.
     51  * Suspend: This command will not return until all pending io to
     52  * the device has completed.  Further io will be deferred until
     53  * the device is resumed.
     54  * Resume: It is no longer an error to issue this command on an
     55  * unsuspended device.  If a table is present in the 'inactive'
     56  * slot, it will be moved to the active slot, then the old table
     57  * from the active slot will be _destroyed_.  Finally the device
     58  * is resumed.
     59  *
     60  * DM_DEV_STATUS:
     61  * Retrieves the status for the table in the 'active' slot.
     62  *
     63  * DM_DEV_WAIT:
     64  * Wait for a significant event to occur to the device.  This
     65  * could either be caused by an event triggered by one of the
     66  * targets of the table in the 'active' slot, or a table change.
     67  *
     68  * DM_TABLE_LOAD:
     69  * Load a table into the 'inactive' slot for the device.  The
     70  * device does _not_ need to be suspended prior to this command.
     71  *
     72  * DM_TABLE_CLEAR:
     73  * Destroy any table in the 'inactive' slot (ie. abort).
     74  *
     75  * DM_TABLE_DEPS:
     76  * Return a set of device dependencies for the 'active' table.
     77  *
     78  * DM_TABLE_STATUS:
     79  * Return the targets status for the 'active' table.
     80  *
     81  * DM_TARGET_MSG:
     82  * Pass a message string to the target at a specific offset of a device.
     83  *
     84  * DM_DEV_SET_GEOMETRY:
     85  * Set the geometry of a device by passing in a string in this format:
     86  *
     87  * "cylinders heads sectors_per_track start_sector"
     88  *
     89  * Beware that CHS geometry is nearly obsolete and only provided
     90  * for compatibility with dm devices that can be booted by a PC
     91  * BIOS.  See struct hd_geometry for range limits.  Also note that
     92  * the geometry is erased if the device size changes.
     93  */
     94 
     95 /*
     96  * All ioctl arguments consist of a single chunk of memory, with
     97  * this structure at the start.  If a uuid is specified any
     98  * lookup (eg. for a DM_INFO) will be done on that, *not* the
     99  * name.
    100  */
    101 struct dm_ioctl {
    102 	/*
    103 	 * The version number is made up of three parts:
    104 	 * major - no backward or forward compatibility,
    105 	 * minor - only backwards compatible,
    106 	 * patch - both backwards and forwards compatible.
    107 	 *
    108 	 * All clients of the ioctl interface should fill in the
    109 	 * version number of the interface that they were
    110 	 * compiled with.
    111 	 *
    112 	 * All recognised ioctl commands (ie. those that don't
    113 	 * return -ENOTTY) fill out this field, even if the
    114 	 * command failed.
    115 	 */
    116 	uint32_t version[3];	/* in/out */
    117 	uint32_t data_size;	/* total size of data passed in
    118 				 * including this struct */
    119 
    120 	uint32_t data_start;	/* offset to start of data
    121 				 * relative to start of this struct */
    122 
    123 	uint32_t target_count;	/* in/out */
    124 	int32_t open_count;	/* out */
    125 	uint32_t flags;		/* in/out */
    126 	uint32_t event_nr;      	/* in/out */
    127 	uint32_t padding;
    128 
    129 	uint64_t dev;		/* in/out */
    130 
    131 	char name[DM_NAME_LEN];	/* device name */
    132 	char uuid[DM_UUID_LEN];	/* unique identifier for
    133 				 * the block device */
    134 	char data[7];		/* padding or data */
    135 };
    136 
    137 /*
    138  * Used to specify tables.  These structures appear after the
    139  * dm_ioctl.
    140  */
    141 struct dm_target_spec {
    142 	uint64_t sector_start;
    143 	uint64_t length;
    144 	int32_t status;		/* used when reading from kernel only */
    145 
    146 	/*
    147 	 * Location of the next dm_target_spec.
    148 	 * - When specifying targets on a DM_TABLE_LOAD command, this value is
    149 	 *   the number of bytes from the start of the "current" dm_target_spec
    150 	 *   to the start of the "next" dm_target_spec.
    151 	 * - When retrieving targets on a DM_TABLE_STATUS command, this value
    152 	 *   is the number of bytes from the start of the first dm_target_spec
    153 	 *   (that follows the dm_ioctl struct) to the start of the "next"
    154 	 *   dm_target_spec.
    155 	 */
    156 	uint32_t next;
    157 
    158 	char target_type[DM_MAX_TYPE_NAME];
    159 
    160 	/*
    161 	 * Parameter string starts immediately after this object.
    162 	 * Be careful to add padding after string to ensure correct
    163 	 * alignment of subsequent dm_target_spec.
    164 	 */
    165 };
    166 
    167 /*
    168  * Used to retrieve the target dependencies.
    169  */
    170 struct dm_target_deps {
    171 	uint32_t count;	/* Array size */
    172 	uint32_t padding;	/* unused */
    173 	uint64_t dev[0];	/* out */
    174 };
    175 
    176 /*
    177  * Used to get a list of all dm devices.
    178  */
    179 struct dm_name_list {
    180 	uint64_t dev;
    181 	uint32_t next;		/* offset to the next record from
    182 				   the _start_ of this */
    183 	char name[0];
    184 };
    185 
    186 /*
    187  * Used to retrieve the target versions
    188  */
    189 struct dm_target_versions {
    190         uint32_t next;
    191         uint32_t version[3];
    192 
    193         char name[0];
    194 };
    195 
    196 /*
    197  * Used to pass message to a target
    198  */
    199 struct dm_target_msg {
    200 	uint64_t sector;	/* Device sector */
    201 
    202 	char message[0];
    203 };
    204 
    205 /*
    206  * If you change this make sure you make the corresponding change
    207  * to dm-ioctl.c:lookup_ioctl()
    208  */
    209 enum {
    210 	/* Top level cmds */
    211 	DM_VERSION_CMD = 0,
    212 	DM_REMOVE_ALL_CMD,
    213 	DM_LIST_DEVICES_CMD,
    214 
    215 	/* device level cmds */
    216 	DM_DEV_CREATE_CMD,
    217 	DM_DEV_REMOVE_CMD,
    218 	DM_DEV_RENAME_CMD,
    219 	DM_DEV_SUSPEND_CMD,
    220 	DM_DEV_STATUS_CMD,
    221 	DM_DEV_WAIT_CMD,
    222 
    223 	/* Table level cmds */
    224 	DM_TABLE_LOAD_CMD,
    225 	DM_TABLE_CLEAR_CMD,
    226 	DM_TABLE_DEPS_CMD,
    227 	DM_TABLE_STATUS_CMD,
    228 
    229 	/* Added later */
    230 	DM_LIST_VERSIONS_CMD,
    231 	DM_TARGET_MSG_CMD,
    232 	DM_DEV_SET_GEOMETRY_CMD
    233 };
    234 
    235 /*
    236  * The dm_ioctl struct passed into the ioctl is just the header
    237  * on a larger chunk of memory.  On x86-64 and other
    238  * architectures the dm-ioctl struct will be padded to an 8 byte
    239  * boundary so the size will be different, which would change the
    240  * ioctl code - yes I really messed up.  This hack forces these
    241  * architectures to have the correct ioctl code.
    242  */
    243 #ifdef CONFIG_COMPAT
    244 typedef char ioctl_struct[308];
    245 #define DM_VERSION_32       _IOWR(DM_IOCTL, DM_VERSION_CMD, ioctl_struct)
    246 #define DM_REMOVE_ALL_32    _IOWR(DM_IOCTL, DM_REMOVE_ALL_CMD, ioctl_struct)
    247 #define DM_LIST_DEVICES_32  _IOWR(DM_IOCTL, DM_LIST_DEVICES_CMD, ioctl_struct)
    248 
    249 #define DM_DEV_CREATE_32    _IOWR(DM_IOCTL, DM_DEV_CREATE_CMD, ioctl_struct)
    250 #define DM_DEV_REMOVE_32    _IOWR(DM_IOCTL, DM_DEV_REMOVE_CMD, ioctl_struct)
    251 #define DM_DEV_RENAME_32    _IOWR(DM_IOCTL, DM_DEV_RENAME_CMD, ioctl_struct)
    252 #define DM_DEV_SUSPEND_32   _IOWR(DM_IOCTL, DM_DEV_SUSPEND_CMD, ioctl_struct)
    253 #define DM_DEV_STATUS_32    _IOWR(DM_IOCTL, DM_DEV_STATUS_CMD, ioctl_struct)
    254 #define DM_DEV_WAIT_32      _IOWR(DM_IOCTL, DM_DEV_WAIT_CMD, ioctl_struct)
    255 
    256 #define DM_TABLE_LOAD_32    _IOWR(DM_IOCTL, DM_TABLE_LOAD_CMD, ioctl_struct)
    257 #define DM_TABLE_CLEAR_32   _IOWR(DM_IOCTL, DM_TABLE_CLEAR_CMD, ioctl_struct)
    258 #define DM_TABLE_DEPS_32    _IOWR(DM_IOCTL, DM_TABLE_DEPS_CMD, ioctl_struct)
    259 #define DM_TABLE_STATUS_32  _IOWR(DM_IOCTL, DM_TABLE_STATUS_CMD, ioctl_struct)
    260 #define DM_LIST_VERSIONS_32 _IOWR(DM_IOCTL, DM_LIST_VERSIONS_CMD, ioctl_struct)
    261 #define DM_TARGET_MSG_32    _IOWR(DM_IOCTL, DM_TARGET_MSG_CMD, ioctl_struct)
    262 #define DM_DEV_SET_GEOMETRY_32	_IOWR(DM_IOCTL, DM_DEV_SET_GEOMETRY_CMD, ioctl_struct)
    263 #endif
    264 
    265 #define DM_IOCTL 0xfd
    266 
    267 #define DM_VERSION       _IOWR(DM_IOCTL, DM_VERSION_CMD, struct dm_ioctl)
    268 #define DM_REMOVE_ALL    _IOWR(DM_IOCTL, DM_REMOVE_ALL_CMD, struct dm_ioctl)
    269 #define DM_LIST_DEVICES  _IOWR(DM_IOCTL, DM_LIST_DEVICES_CMD, struct dm_ioctl)
    270 
    271 #define DM_DEV_CREATE    _IOWR(DM_IOCTL, DM_DEV_CREATE_CMD, struct dm_ioctl)
    272 #define DM_DEV_REMOVE    _IOWR(DM_IOCTL, DM_DEV_REMOVE_CMD, struct dm_ioctl)
    273 #define DM_DEV_RENAME    _IOWR(DM_IOCTL, DM_DEV_RENAME_CMD, struct dm_ioctl)
    274 #define DM_DEV_SUSPEND   _IOWR(DM_IOCTL, DM_DEV_SUSPEND_CMD, struct dm_ioctl)
    275 #define DM_DEV_STATUS    _IOWR(DM_IOCTL, DM_DEV_STATUS_CMD, struct dm_ioctl)
    276 #define DM_DEV_WAIT      _IOWR(DM_IOCTL, DM_DEV_WAIT_CMD, struct dm_ioctl)
    277 
    278 #define DM_TABLE_LOAD    _IOWR(DM_IOCTL, DM_TABLE_LOAD_CMD, struct dm_ioctl)
    279 #define DM_TABLE_CLEAR   _IOWR(DM_IOCTL, DM_TABLE_CLEAR_CMD, struct dm_ioctl)
    280 #define DM_TABLE_DEPS    _IOWR(DM_IOCTL, DM_TABLE_DEPS_CMD, struct dm_ioctl)
    281 #define DM_TABLE_STATUS  _IOWR(DM_IOCTL, DM_TABLE_STATUS_CMD, struct dm_ioctl)
    282 
    283 #define DM_LIST_VERSIONS _IOWR(DM_IOCTL, DM_LIST_VERSIONS_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	4
    289 #define DM_VERSION_MINOR	12
    290 #define DM_VERSION_PATCHLEVEL	0
    291 #define DM_VERSION_EXTRA	"-ioctl (2007-10-02)"
    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 information
    300  * 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 of
    306  * 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 the
    313  * 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  */
    330 #define DM_NOFLUSH_FLAG		(1 << 11) /* In */
    331 
    332 #endif				/* _LINUX_DM_IOCTL_H */
    333