LXR linux/fs/ocfs2/dlm/dlmapi.h

   1/* SPDX-License-Identifier: GPL-2.0-or-later */
   2/* -*- mode: c; c-basic-offset: 8; -*-
   3 * vim: noexpandtab sw=8 ts=8 sts=0:
   4 *
   5 * dlmapi.h
   6 *
   7 * externally exported dlm interfaces
   8 *
   9 * Copyright (C) 2004 Oracle.  All rights reserved.
  10 */
  11
  12#ifndef DLMAPI_H
  13#define DLMAPI_H
  14
  15struct dlm_lock;
  16struct dlm_ctxt;
  17
  18/* NOTE: changes made to this enum should be reflected in dlmdebug.c */
  19enum dlm_status {
  20        DLM_NORMAL = 0,           /*  0: request in progress */
  21        DLM_GRANTED,              /*  1: request granted */
  22        DLM_DENIED,               /*  2: request denied */
  23        DLM_DENIED_NOLOCKS,       /*  3: request denied, out of system resources */
  24        DLM_WORKING,              /*  4: async request in progress */
  25        DLM_BLOCKED,              /*  5: lock request blocked */
  26        DLM_BLOCKED_ORPHAN,       /*  6: lock request blocked by a orphan lock*/
  27        DLM_DENIED_GRACE_PERIOD,  /*  7: topological change in progress */
  28        DLM_SYSERR,               /*  8: system error */
  29        DLM_NOSUPPORT,            /*  9: unsupported */
  30        DLM_CANCELGRANT,          /* 10: can't cancel convert: already granted */
  31        DLM_IVLOCKID,             /* 11: bad lockid */
  32        DLM_SYNC,                 /* 12: synchronous request granted */
  33        DLM_BADTYPE,              /* 13: bad resource type */
  34        DLM_BADRESOURCE,          /* 14: bad resource handle */
  35        DLM_MAXHANDLES,           /* 15: no more resource handles */
  36        DLM_NOCLINFO,             /* 16: can't contact cluster manager */
  37        DLM_NOLOCKMGR,            /* 17: can't contact lock manager */
  38        DLM_NOPURGED,             /* 18: can't contact purge daemon */
  39        DLM_BADARGS,              /* 19: bad api args */
  40        DLM_VOID,                 /* 20: no status */
  41        DLM_NOTQUEUED,            /* 21: NOQUEUE was specified and request failed */
  42        DLM_IVBUFLEN,             /* 22: invalid resource name length */
  43        DLM_CVTUNGRANT,           /* 23: attempted to convert ungranted lock */
  44        DLM_BADPARAM,             /* 24: invalid lock mode specified */
  45        DLM_VALNOTVALID,          /* 25: value block has been invalidated */
  46        DLM_REJECTED,             /* 26: request rejected, unrecognized client */
  47        DLM_ABORT,                /* 27: blocked lock request cancelled */
  48        DLM_CANCEL,               /* 28: conversion request cancelled */
  49        DLM_IVRESHANDLE,          /* 29: invalid resource handle */
  50        DLM_DEADLOCK,             /* 30: deadlock recovery refused this request */
  51        DLM_DENIED_NOASTS,        /* 31: failed to allocate AST */
  52        DLM_FORWARD,              /* 32: request must wait for primary's response */
  53        DLM_TIMEOUT,              /* 33: timeout value for lock has expired */
  54        DLM_IVGROUPID,            /* 34: invalid group specification */
  55        DLM_VERS_CONFLICT,        /* 35: version conflicts prevent request handling */
  56        DLM_BAD_DEVICE_PATH,      /* 36: Locks device does not exist or path wrong */
  57        DLM_NO_DEVICE_PERMISSION, /* 37: Client has insufficient pers for device */
  58        DLM_NO_CONTROL_DEVICE,    /* 38: Cannot set options on opened device */
  59
  60        DLM_RECOVERING,           /* 39: extension, allows caller to fail a lock
  61                                     request if it is being recovered */
  62        DLM_MIGRATING,            /* 40: extension, allows caller to fail a lock
  63                                     request if it is being migrated */
  64        DLM_MAXSTATS,             /* 41: upper limit for return code validation */
  65};
  66
  67/* for pretty-printing dlm_status error messages */
  68const char *dlm_errmsg(enum dlm_status err);
  69/* for pretty-printing dlm_status error names */
  70const char *dlm_errname(enum dlm_status err);
  71
  72/* Eventually the DLM will use standard errno values, but in the
  73 * meantime this lets us track dlm errors as they bubble up. When we
  74 * bring its error reporting into line with the rest of the stack,
  75 * these can just be replaced with calls to mlog_errno. */
  76#define dlm_error(st) do {                                              \
  77        if ((st) != DLM_RECOVERING &&                                   \
  78            (st) != DLM_MIGRATING &&                                    \
  79            (st) != DLM_FORWARD)                                        \
  80                mlog(ML_ERROR, "dlm status = %s\n", dlm_errname((st))); \
  81} while (0)
  82
  83#define DLM_LKSB_UNUSED1           0x01
  84#define DLM_LKSB_PUT_LVB           0x02
  85#define DLM_LKSB_GET_LVB           0x04
  86#define DLM_LKSB_UNUSED2           0x08
  87#define DLM_LKSB_UNUSED3           0x10
  88#define DLM_LKSB_UNUSED4           0x20
  89#define DLM_LKSB_UNUSED5           0x40
  90#define DLM_LKSB_UNUSED6           0x80
  91
  92#define DLM_LVB_LEN  64
  93
  94/* Callers are only allowed access to the lvb and status members of
  95 * this struct. */
  96struct dlm_lockstatus {
  97        enum dlm_status status;
  98        u32 flags;
  99        struct dlm_lock *lockid;
 100        char lvb[DLM_LVB_LEN];
 101};
 102
 103/* Valid lock modes. */
 104#define LKM_IVMODE      (-1)            /* invalid mode */
 105#define LKM_NLMODE      0               /* null lock */
 106#define LKM_CRMODE      1               /* concurrent read    unsupported */
 107#define LKM_CWMODE      2               /* concurrent write   unsupported */
 108#define LKM_PRMODE      3               /* protected read */
 109#define LKM_PWMODE      4               /* protected write    unsupported */
 110#define LKM_EXMODE      5               /* exclusive */
 111#define LKM_MAXMODE     5
 112#define LKM_MODEMASK    0xff
 113
 114/* Flags passed to dlmlock and dlmunlock:
 115 * reserved: flags used by the "real" dlm
 116 * only a few are supported by this dlm
 117 * (U) = unsupported by ocfs2 dlm */
 118#define LKM_ORPHAN       0x00000010  /* this lock is orphanable (U) */
 119#define LKM_PARENTABLE   0x00000020  /* this lock was orphaned (U) */
 120#define LKM_BLOCK        0x00000040  /* blocking lock request (U) */
 121#define LKM_LOCAL        0x00000080  /* local lock request */
 122#define LKM_VALBLK       0x00000100  /* lock value block request */
 123#define LKM_NOQUEUE      0x00000200  /* non blocking request */
 124#define LKM_CONVERT      0x00000400  /* conversion request */
 125#define LKM_NODLCKWT     0x00000800  /* this lock wont deadlock (U) */
 126#define LKM_UNLOCK       0x00001000  /* deallocate this lock */
 127#define LKM_CANCEL       0x00002000  /* cancel conversion request */
 128#define LKM_DEQALL       0x00004000  /* remove all locks held by proc (U) */
 129#define LKM_INVVALBLK    0x00008000  /* invalidate lock value block */
 130#define LKM_SYNCSTS      0x00010000  /* return synchronous status if poss (U) */
 131#define LKM_TIMEOUT      0x00020000  /* lock request contains timeout (U) */
 132#define LKM_SNGLDLCK     0x00040000  /* request can self-deadlock (U) */
 133#define LKM_FINDLOCAL    0x00080000  /* find local lock request (U) */
 134#define LKM_PROC_OWNED   0x00100000  /* owned by process, not group (U) */
 135#define LKM_XID          0x00200000  /* use transaction id for deadlock (U) */
 136#define LKM_XID_CONFLICT 0x00400000  /* do not allow lock inheritance (U) */
 137#define LKM_FORCE        0x00800000  /* force unlock flag */
 138#define LKM_REVVALBLK    0x01000000  /* temporary solution: re-validate
 139                                        lock value block (U) */
 140/* unused */
 141#define LKM_UNUSED1      0x00000001  /* unused */
 142#define LKM_UNUSED2      0x00000002  /* unused */
 143#define LKM_UNUSED3      0x00000004  /* unused */
 144#define LKM_UNUSED4      0x00000008  /* unused */
 145#define LKM_UNUSED5      0x02000000  /* unused */
 146#define LKM_UNUSED6      0x04000000  /* unused */
 147#define LKM_UNUSED7      0x08000000  /* unused */
 148
 149/* ocfs2 extensions: internal only
 150 * should never be used by caller */
 151#define LKM_MIGRATION    0x10000000  /* extension: lockres is to be migrated
 152                                        to another node */
 153#define LKM_PUT_LVB      0x20000000  /* extension: lvb is being passed
 154                                        should be applied to lockres */
 155#define LKM_GET_LVB      0x40000000  /* extension: lvb should be copied
 156                                        from lockres when lock is granted */
 157#define LKM_RECOVERY     0x80000000  /* extension: flag for recovery lock
 158                                        used to avoid recovery rwsem */
 159
 160
 161typedef void (dlm_astlockfunc_t)(void *);
 162typedef void (dlm_bastlockfunc_t)(void *, int);
 163typedef void (dlm_astunlockfunc_t)(void *, enum dlm_status);
 164
 165enum dlm_status dlmlock(struct dlm_ctxt *dlm,
 166                        int mode,
 167                        struct dlm_lockstatus *lksb,
 168                        int flags,
 169                        const char *name,
 170                        int namelen,
 171                        dlm_astlockfunc_t *ast,
 172                        void *data,
 173                        dlm_bastlockfunc_t *bast);
 174
 175enum dlm_status dlmunlock(struct dlm_ctxt *dlm,
 176                          struct dlm_lockstatus *lksb,
 177                          int flags,
 178                          dlm_astunlockfunc_t *unlockast,
 179                          void *data);
 180
 181struct dlm_protocol_version {
 182        u8 pv_major;
 183        u8 pv_minor;
 184};
 185struct dlm_ctxt * dlm_register_domain(const char *domain, u32 key,
 186                                      struct dlm_protocol_version *fs_proto);
 187
 188void dlm_unregister_domain(struct dlm_ctxt *dlm);
 189
 190void dlm_print_one_lock(struct dlm_lock *lockid);
 191
 192typedef void (dlm_eviction_func)(int, void *);
 193struct dlm_eviction_cb {
 194        struct list_head        ec_item;
 195        dlm_eviction_func       *ec_func;
 196        void                    *ec_data;
 197};
 198void dlm_setup_eviction_cb(struct dlm_eviction_cb *cb,
 199                           dlm_eviction_func *f,
 200                           void *data);
 201void dlm_register_eviction_cb(struct dlm_ctxt *dlm,
 202                              struct dlm_eviction_cb *cb);
 203void dlm_unregister_eviction_cb(struct dlm_eviction_cb *cb);
 204
 205#endif /* DLMAPI_H */
 206