drbd.h

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/*
  drbd.h
  Kernel module for 2.6.x Kernels

  This file is part of DRBD by Philipp Reisner and Lars Ellenberg.

  Copyright (C) 2001-2008, LINBIT Information Technologies GmbH.
  Copyright (C) 2001-2008, Philipp Reisner <[email protected]>.
  Copyright (C) 2001-2008, Lars Ellenberg <[email protected]>.

  drbd is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2, or (at your option)
  any later version.

  drbd is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with drbd; see the file COPYING.  If not, write to
  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.

*/
#ifndef DRBD_H
#define DRBD_H
#include <linux/connector.h>
#include <asm/types.h>

#ifdef __KERNEL__
#include <linux/types.h>
#include <asm/byteorder.h>
#else
#include <sys/types.h>
#include <sys/wait.h>
#include <limits.h>

/* Although the Linux source code makes a difference between
   generic endianness and the bitfields' endianness, there is no
   architecture as of Linux-2.6.24-rc4 where the bitfields' endianness
   does not match the generic endianness. */

#if __BYTE_ORDER == __LITTLE_ENDIAN
#define __LITTLE_ENDIAN_BITFIELD
#elif __BYTE_ORDER == __BIG_ENDIAN
#define __BIG_ENDIAN_BITFIELD
#else
# error "sorry, weird endianness on this box"
#endif

#endif


extern const char *drbd_buildtag(void);
#define REL_VERSION "8.3.13"
#define API_VERSION 88
#define PRO_VERSION_MIN 86
#define PRO_VERSION_MAX 96


enum drbd_io_error_p {
    EP_PASS_ON, /* FIXME should the better be named "Ignore"? */
    EP_CALL_HELPER,
    EP_DETACH
};

enum drbd_fencing_p {
    FP_DONT_CARE,
    FP_RESOURCE,
    FP_STONITH
};

enum drbd_disconnect_p {
    DP_RECONNECT,
    DP_DROP_NET_CONF,
    DP_FREEZE_IO
};

enum drbd_after_sb_p {
    ASB_DISCONNECT,
    ASB_DISCARD_YOUNGER_PRI,
    ASB_DISCARD_OLDER_PRI,
    ASB_DISCARD_ZERO_CHG,
    ASB_DISCARD_LEAST_CHG,
    ASB_DISCARD_LOCAL,
    ASB_DISCARD_REMOTE,
    ASB_CONSENSUS,
    ASB_DISCARD_SECONDARY,
    ASB_CALL_HELPER,
    ASB_VIOLENTLY
};

enum drbd_on_no_data {
    OND_IO_ERROR,
    OND_SUSPEND_IO
};

enum drbd_on_congestion {
    OC_BLOCK,
    OC_PULL_AHEAD,
    OC_DISCONNECT,
};

/* KEEP the order, do not delete or insert. Only append. */
enum drbd_ret_code {
    ERR_CODE_BASE       = 100,
    NO_ERROR        = 101,
    ERR_LOCAL_ADDR      = 102,
    ERR_PEER_ADDR       = 103,
    ERR_OPEN_DISK       = 104,
    ERR_OPEN_MD_DISK    = 105,
    ERR_DISK_NOT_BDEV   = 107,
    ERR_MD_NOT_BDEV     = 108,
    ERR_DISK_TOO_SMALL  = 111,
    ERR_MD_DISK_TOO_SMALL   = 112,
    ERR_BDCLAIM_DISK    = 114,
    ERR_BDCLAIM_MD_DISK = 115,
    ERR_MD_IDX_INVALID  = 116,
    ERR_IO_MD_DISK      = 118,
    ERR_MD_INVALID          = 119,
    ERR_AUTH_ALG        = 120,
    ERR_AUTH_ALG_ND     = 121,
    ERR_NOMEM       = 122,
    ERR_DISCARD     = 123,
    ERR_DISK_CONFIGURED = 124,
    ERR_NET_CONFIGURED  = 125,
    ERR_MANDATORY_TAG   = 126,
    ERR_MINOR_INVALID   = 127,
    ERR_INTR        = 129, /* EINTR */
    ERR_RESIZE_RESYNC   = 130,
    ERR_NO_PRIMARY      = 131,
    ERR_SYNC_AFTER      = 132,
    ERR_SYNC_AFTER_CYCLE    = 133,
    ERR_PAUSE_IS_SET    = 134,
    ERR_PAUSE_IS_CLEAR  = 135,
    ERR_PACKET_NR       = 137,
    ERR_NO_DISK     = 138,
    ERR_NOT_PROTO_C     = 139,
    ERR_NOMEM_BITMAP    = 140,
    ERR_INTEGRITY_ALG   = 141, /* DRBD 8.2 only */
    ERR_INTEGRITY_ALG_ND    = 142, /* DRBD 8.2 only */
    ERR_CPU_MASK_PARSE  = 143, /* DRBD 8.2 only */
    ERR_CSUMS_ALG       = 144, /* DRBD 8.2 only */
    ERR_CSUMS_ALG_ND    = 145, /* DRBD 8.2 only */
    ERR_VERIFY_ALG      = 146, /* DRBD 8.2 only */
    ERR_VERIFY_ALG_ND   = 147, /* DRBD 8.2 only */
    ERR_CSUMS_RESYNC_RUNNING= 148, /* DRBD 8.2 only */
    ERR_VERIFY_RUNNING  = 149, /* DRBD 8.2 only */
    ERR_DATA_NOT_CURRENT    = 150,
    ERR_CONNECTED       = 151, /* DRBD 8.3 only */
    ERR_PERM        = 152,
    ERR_NEED_APV_93     = 153,
    ERR_STONITH_AND_PROT_A  = 154,
    ERR_CONG_NOT_PROTO_A    = 155,
    ERR_PIC_AFTER_DEP   = 156,
    ERR_PIC_PEER_DEP    = 157,

    /* insert new ones above this line */
    AFTER_LAST_ERR_CODE
};

#define DRBD_PROT_A   1
#define DRBD_PROT_B   2
#define DRBD_PROT_C   3

enum drbd_role {
    R_UNKNOWN = 0,
    R_PRIMARY = 1,     /* role */
    R_SECONDARY = 2,   /* role */
    R_MASK = 3,
};

/* The order of these constants is important.
 * The lower ones (<C_WF_REPORT_PARAMS) indicate
 * that there is no socket!
 * >=C_WF_REPORT_PARAMS ==> There is a socket
 */
enum drbd_conns {
    C_STANDALONE,
    C_DISCONNECTING,  /* Temporal state on the way to StandAlone. */
    C_UNCONNECTED,    /* >= C_UNCONNECTED -> inc_net() succeeds */

    /* These temporal states are all used on the way
     * from >= C_CONNECTED to Unconnected.
     * The 'disconnect reason' states
     * I do not allow to change between them. */
    C_TIMEOUT,
    C_BROKEN_PIPE,
    C_NETWORK_FAILURE,
    C_PROTOCOL_ERROR,
    C_TEAR_DOWN,

    C_WF_CONNECTION,
    C_WF_REPORT_PARAMS, /* we have a socket */
    C_CONNECTED,      /* we have introduced each other */
    C_STARTING_SYNC_S,  /* starting full sync by admin request. */
    C_STARTING_SYNC_T,  /* starting full sync by admin request. */
    C_WF_BITMAP_S,
    C_WF_BITMAP_T,
    C_WF_SYNC_UUID,

    /* All SyncStates are tested with this comparison
     * xx >= C_SYNC_SOURCE && xx <= C_PAUSED_SYNC_T */
    C_SYNC_SOURCE,
    C_SYNC_TARGET,
    C_VERIFY_S,
    C_VERIFY_T,
    C_PAUSED_SYNC_S,
    C_PAUSED_SYNC_T,

    C_AHEAD,
    C_BEHIND,

    C_MASK = 31
};

enum drbd_disk_state {
    D_DISKLESS,
    D_ATTACHING,      /* In the process of reading the meta-data */
    D_FAILED,         /* Becomes D_DISKLESS as soon as we told it the peer */
            /* when >= D_FAILED it is legal to access mdev->bc */
    D_NEGOTIATING,    /* Late attaching state, we need to talk to the peer */
    D_INCONSISTENT,
    D_OUTDATED,
    D_UNKNOWN,       /* Only used for the peer, never for myself */
    D_CONSISTENT,     /* Might be D_OUTDATED, might be D_UP_TO_DATE ... */
    D_UP_TO_DATE,       /* Only this disk state allows applications' IO ! */
    D_MASK = 15
};

union drbd_state {
/* According to gcc's docs is the ...
 * The order of allocation of bit-fields within a unit (C90 6.5.2.1, C99 6.7.2.1).
 * Determined by ABI.
 * pointed out by Maxim Uvarov q<[email protected]>
 * even though we transmit as "cpu_to_be32(state)",
 * the offsets of the bitfields still need to be swapped
 * on different endianness.
 */
    struct {
#if defined(__LITTLE_ENDIAN_BITFIELD)
        unsigned role:2 ;   /* 3/4   primary/secondary/unknown */
        unsigned peer:2 ;   /* 3/4   primary/secondary/unknown */
        unsigned conn:5 ;   /* 17/32     cstates */
        unsigned disk:4 ;   /* 8/16  from D_DISKLESS to D_UP_TO_DATE */
        unsigned pdsk:4 ;   /* 8/16  from D_DISKLESS to D_UP_TO_DATE */
        unsigned susp:1 ;   /* 2/2   IO suspended no/yes (by user) */
        unsigned aftr_isp:1 ; /* isp .. imposed sync pause */
        unsigned peer_isp:1 ;
        unsigned user_isp:1 ;
        unsigned susp_nod:1 ; /* IO suspended because no data */
        unsigned susp_fen:1 ; /* IO suspended because fence peer handler runs*/
        unsigned _pad:9;   /* 0  unused */
#elif defined(__BIG_ENDIAN_BITFIELD)
        unsigned _pad:9;
        unsigned susp_fen:1 ;
        unsigned susp_nod:1 ;
        unsigned user_isp:1 ;
        unsigned peer_isp:1 ;
        unsigned aftr_isp:1 ; /* isp .. imposed sync pause */
        unsigned susp:1 ;   /* 2/2   IO suspended  no/yes */
        unsigned pdsk:4 ;   /* 8/16  from D_DISKLESS to D_UP_TO_DATE */
        unsigned disk:4 ;   /* 8/16  from D_DISKLESS to D_UP_TO_DATE */
        unsigned conn:5 ;   /* 17/32     cstates */
        unsigned peer:2 ;   /* 3/4   primary/secondary/unknown */
        unsigned role:2 ;   /* 3/4   primary/secondary/unknown */
#else
# error "this endianness is not supported"
#endif
    };
    unsigned int i;
};

enum drbd_state_rv {
    SS_CW_NO_NEED = 4,
    SS_CW_SUCCESS = 3,
    SS_NOTHING_TO_DO = 2,
    SS_SUCCESS = 1,
    SS_UNKNOWN_ERROR = 0, /* Used to sleep longer in _drbd_request_state */
    SS_TWO_PRIMARIES = -1,
    SS_NO_UP_TO_DATE_DISK = -2,
    SS_NO_LOCAL_DISK = -4,
    SS_NO_REMOTE_DISK = -5,
    SS_CONNECTED_OUTDATES = -6,
    SS_PRIMARY_NOP = -7,
    SS_RESYNC_RUNNING = -8,
    SS_ALREADY_STANDALONE = -9,
    SS_CW_FAILED_BY_PEER = -10,
    SS_IS_DISKLESS = -11,
    SS_DEVICE_IN_USE = -12,
    SS_NO_NET_CONFIG = -13,
    SS_NO_VERIFY_ALG = -14,       /* drbd-8.2 only */
    SS_NEED_CONNECTION = -15,    /* drbd-8.2 only */
    SS_LOWER_THAN_OUTDATED = -16,
    SS_NOT_SUPPORTED = -17,      /* drbd-8.2 only */
    SS_IN_TRANSIENT_STATE = -18,  /* Retry after the next state change */
    SS_CONCURRENT_ST_CHG = -19,   /* Concurrent cluster side state change! */
    SS_AFTER_LAST_ERROR = -20,    /* Keep this at bottom */
};

/* from drbd_strings.c */
extern const char *drbd_conn_str(enum drbd_conns);
extern const char *drbd_role_str(enum drbd_role);
extern const char *drbd_disk_str(enum drbd_disk_state);
extern const char *drbd_set_st_err_str(enum drbd_state_rv);

#define SHARED_SECRET_MAX 64

#define MDF_CONSISTENT      (1 << 0)
#define MDF_PRIMARY_IND     (1 << 1)
#define MDF_CONNECTED_IND   (1 << 2)
#define MDF_FULL_SYNC       (1 << 3)
#define MDF_WAS_UP_TO_DATE  (1 << 4)
#define MDF_PEER_OUT_DATED  (1 << 5)
#define MDF_CRASHED_PRIMARY     (1 << 6)

enum drbd_uuid_index {
    UI_CURRENT,
    UI_BITMAP,
    UI_HISTORY_START,
    UI_HISTORY_END,
    UI_SIZE,      /* nl-packet: number of dirty bits */
    UI_FLAGS,     /* nl-packet: flags */
    UI_EXTENDED_SIZE   /* Everything. */
};

enum drbd_timeout_flag {
    UT_DEFAULT      = 0,
    UT_DEGRADED     = 1,
    UT_PEER_OUTDATED = 2,
};

#define UUID_JUST_CREATED ((__u64)4)

#define DRBD_MAGIC 0x83740267
#define BE_DRBD_MAGIC __constant_cpu_to_be32(DRBD_MAGIC)
#define DRBD_MAGIC_BIG 0x835a
#define BE_DRBD_MAGIC_BIG __constant_cpu_to_be16(DRBD_MAGIC_BIG)

/* these are of type "int" */
#define DRBD_MD_INDEX_INTERNAL -1
#define DRBD_MD_INDEX_FLEX_EXT -2
#define DRBD_MD_INDEX_FLEX_INT -3

/* Start of the new netlink/connector stuff */

#define DRBD_NL_CREATE_DEVICE 0x01
#define DRBD_NL_SET_DEFAULTS  0x02


/* For searching a vacant cn_idx value */
#define CN_IDX_STEP         6977

struct drbd_nl_cfg_req {
    int packet_type;
    unsigned int drbd_minor;
    int flags;
    unsigned short tag_list[];
};

struct drbd_nl_cfg_reply {
    int packet_type;
    unsigned int minor;
    int ret_code; /* enum ret_code or set_st_err_t */
    unsigned short tag_list[]; /* only used with get_* calls */
};

#endif