LXR linux/include/linux/drbd.h

   1/*
   2  drbd.h
   3  Kernel module for 2.6.x Kernels
   4
   5  This file is part of DRBD by Philipp Reisner and Lars Ellenberg.
   6
   7  Copyright (C) 2001-2008, LINBIT Information Technologies GmbH.
   8  Copyright (C) 2001-2008, Philipp Reisner <philipp.reisner@linbit.com>.
   9  Copyright (C) 2001-2008, Lars Ellenberg <lars.ellenberg@linbit.com>.
  10
  11  drbd is free software; you can redistribute it and/or modify
  12  it under the terms of the GNU General Public License as published by
  13  the Free Software Foundation; either version 2, or (at your option)
  14  any later version.
  15
  16  drbd is distributed in the hope that it will be useful,
  17  but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  GNU General Public License for more details.
  20
  21  You should have received a copy of the GNU General Public License
  22  along with drbd; see the file COPYING.  If not, write to
  23  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  24
  25*/
  26#ifndef DRBD_H
  27#define DRBD_H
  28#include <linux/connector.h>
  29#include <asm/types.h>
  30
  31#ifdef __KERNEL__
  32#include <linux/types.h>
  33#include <asm/byteorder.h>
  34#else
  35#include <sys/types.h>
  36#include <sys/wait.h>
  37#include <limits.h>
  38
  39/* Although the Linux source code makes a difference between
  40   generic endianness and the bitfields' endianness, there is no
  41   architecture as of Linux-2.6.24-rc4 where the bitfields' endianness
  42   does not match the generic endianness. */
  43
  44#if __BYTE_ORDER == __LITTLE_ENDIAN
  45#define __LITTLE_ENDIAN_BITFIELD
  46#elif __BYTE_ORDER == __BIG_ENDIAN
  47#define __BIG_ENDIAN_BITFIELD
  48#else
  49# error "sorry, weird endianness on this box"
  50#endif
  51
  52#endif
  53
  54extern const char *drbd_buildtag(void);
  55#define REL_VERSION "8.4.3"
  56#define API_VERSION 1
  57#define PRO_VERSION_MIN 86
  58#define PRO_VERSION_MAX 101
  59
  60
  61enum drbd_io_error_p {
  62        EP_PASS_ON, /* FIXME should the better be named "Ignore"? */
  63        EP_CALL_HELPER,
  64        EP_DETACH
  65};
  66
  67enum drbd_fencing_p {
  68        FP_NOT_AVAIL = -1, /* Not a policy */
  69        FP_DONT_CARE = 0,
  70        FP_RESOURCE,
  71        FP_STONITH
  72};
  73
  74enum drbd_disconnect_p {
  75        DP_RECONNECT,
  76        DP_DROP_NET_CONF,
  77        DP_FREEZE_IO
  78};
  79
  80enum drbd_after_sb_p {
  81        ASB_DISCONNECT,
  82        ASB_DISCARD_YOUNGER_PRI,
  83        ASB_DISCARD_OLDER_PRI,
  84        ASB_DISCARD_ZERO_CHG,
  85        ASB_DISCARD_LEAST_CHG,
  86        ASB_DISCARD_LOCAL,
  87        ASB_DISCARD_REMOTE,
  88        ASB_CONSENSUS,
  89        ASB_DISCARD_SECONDARY,
  90        ASB_CALL_HELPER,
  91        ASB_VIOLENTLY
  92};
  93
  94enum drbd_on_no_data {
  95        OND_IO_ERROR,
  96        OND_SUSPEND_IO
  97};
  98
  99enum drbd_on_congestion {
 100        OC_BLOCK,
 101        OC_PULL_AHEAD,
 102        OC_DISCONNECT,
 103};
 104
 105enum drbd_read_balancing {
 106        RB_PREFER_LOCAL,
 107        RB_PREFER_REMOTE,
 108        RB_ROUND_ROBIN,
 109        RB_LEAST_PENDING,
 110        RB_CONGESTED_REMOTE,
 111        RB_32K_STRIPING,
 112        RB_64K_STRIPING,
 113        RB_128K_STRIPING,
 114        RB_256K_STRIPING,
 115        RB_512K_STRIPING,
 116        RB_1M_STRIPING,
 117};
 118
 119/* KEEP the order, do not delete or insert. Only append. */
 120enum drbd_ret_code {
 121        ERR_CODE_BASE           = 100,
 122        NO_ERROR                = 101,
 123        ERR_LOCAL_ADDR          = 102,
 124        ERR_PEER_ADDR           = 103,
 125        ERR_OPEN_DISK           = 104,
 126        ERR_OPEN_MD_DISK        = 105,
 127        ERR_DISK_NOT_BDEV       = 107,
 128        ERR_MD_NOT_BDEV         = 108,
 129        ERR_DISK_TOO_SMALL      = 111,
 130        ERR_MD_DISK_TOO_SMALL   = 112,
 131        ERR_BDCLAIM_DISK        = 114,
 132        ERR_BDCLAIM_MD_DISK     = 115,
 133        ERR_MD_IDX_INVALID      = 116,
 134        ERR_IO_MD_DISK          = 118,
 135        ERR_MD_INVALID          = 119,
 136        ERR_AUTH_ALG            = 120,
 137        ERR_AUTH_ALG_ND         = 121,
 138        ERR_NOMEM               = 122,
 139        ERR_DISCARD_IMPOSSIBLE  = 123,
 140        ERR_DISK_CONFIGURED     = 124,
 141        ERR_NET_CONFIGURED      = 125,
 142        ERR_MANDATORY_TAG       = 126,
 143        ERR_MINOR_INVALID       = 127,
 144        ERR_INTR                = 129, /* EINTR */
 145        ERR_RESIZE_RESYNC       = 130,
 146        ERR_NO_PRIMARY          = 131,
 147        ERR_RESYNC_AFTER        = 132,
 148        ERR_RESYNC_AFTER_CYCLE  = 133,
 149        ERR_PAUSE_IS_SET        = 134,
 150        ERR_PAUSE_IS_CLEAR      = 135,
 151        ERR_PACKET_NR           = 137,
 152        ERR_NO_DISK             = 138,
 153        ERR_NOT_PROTO_C         = 139,
 154        ERR_NOMEM_BITMAP        = 140,
 155        ERR_INTEGRITY_ALG       = 141, /* DRBD 8.2 only */
 156        ERR_INTEGRITY_ALG_ND    = 142, /* DRBD 8.2 only */
 157        ERR_CPU_MASK_PARSE      = 143, /* DRBD 8.2 only */
 158        ERR_CSUMS_ALG           = 144, /* DRBD 8.2 only */
 159        ERR_CSUMS_ALG_ND        = 145, /* DRBD 8.2 only */
 160        ERR_VERIFY_ALG          = 146, /* DRBD 8.2 only */
 161        ERR_VERIFY_ALG_ND       = 147, /* DRBD 8.2 only */
 162        ERR_CSUMS_RESYNC_RUNNING= 148, /* DRBD 8.2 only */
 163        ERR_VERIFY_RUNNING      = 149, /* DRBD 8.2 only */
 164        ERR_DATA_NOT_CURRENT    = 150,
 165        ERR_CONNECTED           = 151, /* DRBD 8.3 only */
 166        ERR_PERM                = 152,
 167        ERR_NEED_APV_93         = 153,
 168        ERR_STONITH_AND_PROT_A  = 154,
 169        ERR_CONG_NOT_PROTO_A    = 155,
 170        ERR_PIC_AFTER_DEP       = 156,
 171        ERR_PIC_PEER_DEP        = 157,
 172        ERR_RES_NOT_KNOWN       = 158,
 173        ERR_RES_IN_USE          = 159,
 174        ERR_MINOR_CONFIGURED    = 160,
 175        ERR_MINOR_EXISTS        = 161,
 176        ERR_INVALID_REQUEST     = 162,
 177        ERR_NEED_APV_100        = 163,
 178        ERR_NEED_ALLOW_TWO_PRI  = 164,
 179        ERR_MD_UNCLEAN          = 165,
 180
 181        /* insert new ones above this line */
 182        AFTER_LAST_ERR_CODE
 183};
 184
 185#define DRBD_PROT_A   1
 186#define DRBD_PROT_B   2
 187#define DRBD_PROT_C   3
 188
 189enum drbd_role {
 190        R_UNKNOWN = 0,
 191        R_PRIMARY = 1,     /* role */
 192        R_SECONDARY = 2,   /* role */
 193        R_MASK = 3,
 194};
 195
 196/* The order of these constants is important.
 197 * The lower ones (<C_WF_REPORT_PARAMS) indicate
 198 * that there is no socket!
 199 * >=C_WF_REPORT_PARAMS ==> There is a socket
 200 */
 201enum drbd_conns {
 202        C_STANDALONE,
 203        C_DISCONNECTING,  /* Temporal state on the way to StandAlone. */
 204        C_UNCONNECTED,    /* >= C_UNCONNECTED -> inc_net() succeeds */
 205
 206        /* These temporal states are all used on the way
 207         * from >= C_CONNECTED to Unconnected.
 208         * The 'disconnect reason' states
 209         * I do not allow to change between them. */
 210        C_TIMEOUT,
 211        C_BROKEN_PIPE,
 212        C_NETWORK_FAILURE,
 213        C_PROTOCOL_ERROR,
 214        C_TEAR_DOWN,
 215
 216        C_WF_CONNECTION,
 217        C_WF_REPORT_PARAMS, /* we have a socket */
 218        C_CONNECTED,      /* we have introduced each other */
 219        C_STARTING_SYNC_S,  /* starting full sync by admin request. */
 220        C_STARTING_SYNC_T,  /* starting full sync by admin request. */
 221        C_WF_BITMAP_S,
 222        C_WF_BITMAP_T,
 223        C_WF_SYNC_UUID,
 224
 225        /* All SyncStates are tested with this comparison
 226         * xx >= C_SYNC_SOURCE && xx <= C_PAUSED_SYNC_T */
 227        C_SYNC_SOURCE,
 228        C_SYNC_TARGET,
 229        C_VERIFY_S,
 230        C_VERIFY_T,
 231        C_PAUSED_SYNC_S,
 232        C_PAUSED_SYNC_T,
 233
 234        C_AHEAD,
 235        C_BEHIND,
 236
 237        C_MASK = 31
 238};
 239
 240enum drbd_disk_state {
 241        D_DISKLESS,
 242        D_ATTACHING,      /* In the process of reading the meta-data */
 243        D_FAILED,         /* Becomes D_DISKLESS as soon as we told it the peer */
 244                        /* when >= D_FAILED it is legal to access mdev->bc */
 245        D_NEGOTIATING,    /* Late attaching state, we need to talk to the peer */
 246        D_INCONSISTENT,
 247        D_OUTDATED,
 248        D_UNKNOWN,       /* Only used for the peer, never for myself */
 249        D_CONSISTENT,     /* Might be D_OUTDATED, might be D_UP_TO_DATE ... */
 250        D_UP_TO_DATE,       /* Only this disk state allows applications' IO ! */
 251        D_MASK = 15
 252};
 253
 254union drbd_state {
 255/* According to gcc's docs is the ...
 256 * The order of allocation of bit-fields within a unit (C90 6.5.2.1, C99 6.7.2.1).
 257 * Determined by ABI.
 258 * pointed out by Maxim Uvarov q<muvarov@ru.mvista.com>
 259 * even though we transmit as "cpu_to_be32(state)",
 260 * the offsets of the bitfields still need to be swapped
 261 * on different endianness.
 262 */
 263        struct {
 264#if defined(__LITTLE_ENDIAN_BITFIELD)
 265                unsigned role:2 ;   /* 3/4       primary/secondary/unknown */
 266                unsigned peer:2 ;   /* 3/4       primary/secondary/unknown */
 267                unsigned conn:5 ;   /* 17/32     cstates */
 268                unsigned disk:4 ;   /* 8/16      from D_DISKLESS to D_UP_TO_DATE */
 269                unsigned pdsk:4 ;   /* 8/16      from D_DISKLESS to D_UP_TO_DATE */
 270                unsigned susp:1 ;   /* 2/2       IO suspended no/yes (by user) */
 271                unsigned aftr_isp:1 ; /* isp .. imposed sync pause */
 272                unsigned peer_isp:1 ;
 273                unsigned user_isp:1 ;
 274                unsigned susp_nod:1 ; /* IO suspended because no data */
 275                unsigned susp_fen:1 ; /* IO suspended because fence peer handler runs*/
 276                unsigned _pad:9;   /* 0  unused */
 277#elif defined(__BIG_ENDIAN_BITFIELD)
 278                unsigned _pad:9;
 279                unsigned susp_fen:1 ;
 280                unsigned susp_nod:1 ;
 281                unsigned user_isp:1 ;
 282                unsigned peer_isp:1 ;
 283                unsigned aftr_isp:1 ; /* isp .. imposed sync pause */
 284                unsigned susp:1 ;   /* 2/2       IO suspended  no/yes */
 285                unsigned pdsk:4 ;   /* 8/16      from D_DISKLESS to D_UP_TO_DATE */
 286                unsigned disk:4 ;   /* 8/16      from D_DISKLESS to D_UP_TO_DATE */
 287                unsigned conn:5 ;   /* 17/32     cstates */
 288                unsigned peer:2 ;   /* 3/4       primary/secondary/unknown */
 289                unsigned role:2 ;   /* 3/4       primary/secondary/unknown */
 290#else
 291# error "this endianness is not supported"
 292#endif
 293        };
 294        unsigned int i;
 295};
 296
 297enum drbd_state_rv {
 298        SS_CW_NO_NEED = 4,
 299        SS_CW_SUCCESS = 3,
 300        SS_NOTHING_TO_DO = 2,
 301        SS_SUCCESS = 1,
 302        SS_UNKNOWN_ERROR = 0, /* Used to sleep longer in _drbd_request_state */
 303        SS_TWO_PRIMARIES = -1,
 304        SS_NO_UP_TO_DATE_DISK = -2,
 305        SS_NO_LOCAL_DISK = -4,
 306        SS_NO_REMOTE_DISK = -5,
 307        SS_CONNECTED_OUTDATES = -6,
 308        SS_PRIMARY_NOP = -7,
 309        SS_RESYNC_RUNNING = -8,
 310        SS_ALREADY_STANDALONE = -9,
 311        SS_CW_FAILED_BY_PEER = -10,
 312        SS_IS_DISKLESS = -11,
 313        SS_DEVICE_IN_USE = -12,
 314        SS_NO_NET_CONFIG = -13,
 315        SS_NO_VERIFY_ALG = -14,       /* drbd-8.2 only */
 316        SS_NEED_CONNECTION = -15,    /* drbd-8.2 only */
 317        SS_LOWER_THAN_OUTDATED = -16,
 318        SS_NOT_SUPPORTED = -17,      /* drbd-8.2 only */
 319        SS_IN_TRANSIENT_STATE = -18,  /* Retry after the next state change */
 320        SS_CONCURRENT_ST_CHG = -19,   /* Concurrent cluster side state change! */
 321        SS_O_VOL_PEER_PRI = -20,
 322        SS_OUTDATE_WO_CONN = -21,
 323        SS_AFTER_LAST_ERROR = -22,    /* Keep this at bottom */
 324};
 325
 326/* from drbd_strings.c */
 327extern const char *drbd_conn_str(enum drbd_conns);
 328extern const char *drbd_role_str(enum drbd_role);
 329extern const char *drbd_disk_str(enum drbd_disk_state);
 330extern const char *drbd_set_st_err_str(enum drbd_state_rv);
 331
 332#define SHARED_SECRET_MAX 64
 333
 334#define MDF_CONSISTENT          (1 << 0)
 335#define MDF_PRIMARY_IND         (1 << 1)
 336#define MDF_CONNECTED_IND       (1 << 2)
 337#define MDF_FULL_SYNC           (1 << 3)
 338#define MDF_WAS_UP_TO_DATE      (1 << 4)
 339#define MDF_PEER_OUT_DATED      (1 << 5)
 340#define MDF_CRASHED_PRIMARY     (1 << 6)
 341#define MDF_AL_CLEAN            (1 << 7)
 342#define MDF_AL_DISABLED         (1 << 8)
 343
 344enum drbd_uuid_index {
 345        UI_CURRENT,
 346        UI_BITMAP,
 347        UI_HISTORY_START,
 348        UI_HISTORY_END,
 349        UI_SIZE,      /* nl-packet: number of dirty bits */
 350        UI_FLAGS,     /* nl-packet: flags */
 351        UI_EXTENDED_SIZE   /* Everything. */
 352};
 353
 354enum drbd_timeout_flag {
 355        UT_DEFAULT      = 0,
 356        UT_DEGRADED     = 1,
 357        UT_PEER_OUTDATED = 2,
 358};
 359
 360#define UUID_JUST_CREATED ((__u64)4)
 361
 362/* magic numbers used in meta data and network packets */
 363#define DRBD_MAGIC 0x83740267
 364#define DRBD_MAGIC_BIG 0x835a
 365#define DRBD_MAGIC_100 0x8620ec20
 366
 367#define DRBD_MD_MAGIC_07   (DRBD_MAGIC+3)
 368#define DRBD_MD_MAGIC_08   (DRBD_MAGIC+4)
 369#define DRBD_MD_MAGIC_84_UNCLEAN        (DRBD_MAGIC+5)
 370
 371
 372/* how I came up with this magic?
 373 * base64 decode "actlog==" ;) */
 374#define DRBD_AL_MAGIC 0x69cb65a2
 375
 376/* these are of type "int" */
 377#define DRBD_MD_INDEX_INTERNAL -1
 378#define DRBD_MD_INDEX_FLEX_EXT -2
 379#define DRBD_MD_INDEX_FLEX_INT -3
 380
 381#endif
 382