ocfs2/dlm/dlmapi.h

0001 /* SPDX-License-Identifier: GPL-2.0-or-later */
0002 /*
0003  * dlmapi.h
0004  *
0005  * externally exported dlm interfaces
0006  *
0007  * Copyright (C) 2004 Oracle.  All rights reserved.
0008  */
0009
0010 #ifndef DLMAPI_H
0011 #define DLMAPI_H
0012
0013 struct dlm_lock;
0014 struct dlm_ctxt;
0015
0016 /* NOTE: changes made to this enum should be reflected in dlmdebug.c */
0017 enum dlm_status {
0018     DLM_NORMAL = 0,           /*  0: request in progress */
0019     DLM_GRANTED,              /*  1: request granted */
0020     DLM_DENIED,               /*  2: request denied */
0021     DLM_DENIED_NOLOCKS,       /*  3: request denied, out of system resources */
0022     DLM_WORKING,              /*  4: async request in progress */
0023     DLM_BLOCKED,              /*  5: lock request blocked */
0024     DLM_BLOCKED_ORPHAN,       /*  6: lock request blocked by a orphan lock*/
0025     DLM_DENIED_GRACE_PERIOD,  /*  7: topological change in progress */
0026     DLM_SYSERR,               /*  8: system error */
0027     DLM_NOSUPPORT,            /*  9: unsupported */
0028     DLM_CANCELGRANT,          /* 10: can't cancel convert: already granted */
0029     DLM_IVLOCKID,             /* 11: bad lockid */
0030     DLM_SYNC,                 /* 12: synchronous request granted */
0031     DLM_BADTYPE,              /* 13: bad resource type */
0032     DLM_BADRESOURCE,          /* 14: bad resource handle */
0033     DLM_MAXHANDLES,           /* 15: no more resource handles */
0034     DLM_NOCLINFO,             /* 16: can't contact cluster manager */
0035     DLM_NOLOCKMGR,            /* 17: can't contact lock manager */
0036     DLM_NOPURGED,             /* 18: can't contact purge daemon */
0037     DLM_BADARGS,              /* 19: bad api args */
0038     DLM_VOID,                 /* 20: no status */
0039     DLM_NOTQUEUED,            /* 21: NOQUEUE was specified and request failed */
0040     DLM_IVBUFLEN,             /* 22: invalid resource name length */
0041     DLM_CVTUNGRANT,           /* 23: attempted to convert ungranted lock */
0042     DLM_BADPARAM,             /* 24: invalid lock mode specified */
0043     DLM_VALNOTVALID,          /* 25: value block has been invalidated */
0044     DLM_REJECTED,             /* 26: request rejected, unrecognized client */
0045     DLM_ABORT,                /* 27: blocked lock request cancelled */
0046     DLM_CANCEL,               /* 28: conversion request cancelled */
0047     DLM_IVRESHANDLE,          /* 29: invalid resource handle */
0048     DLM_DEADLOCK,             /* 30: deadlock recovery refused this request */
0049     DLM_DENIED_NOASTS,        /* 31: failed to allocate AST */
0050     DLM_FORWARD,              /* 32: request must wait for primary's response */
0051     DLM_TIMEOUT,              /* 33: timeout value for lock has expired */
0052     DLM_IVGROUPID,            /* 34: invalid group specification */
0053     DLM_VERS_CONFLICT,        /* 35: version conflicts prevent request handling */
0054     DLM_BAD_DEVICE_PATH,      /* 36: Locks device does not exist or path wrong */
0055     DLM_NO_DEVICE_PERMISSION, /* 37: Client has insufficient pers for device */
0056     DLM_NO_CONTROL_DEVICE,    /* 38: Cannot set options on opened device */
0057
0058     DLM_RECOVERING,           /* 39: extension, allows caller to fail a lock
0059                      request if it is being recovered */
0060     DLM_MIGRATING,            /* 40: extension, allows caller to fail a lock
0061                      request if it is being migrated */
0062     DLM_MAXSTATS,             /* 41: upper limit for return code validation */
0063 };
0064
0065 /* for pretty-printing dlm_status error messages */
0066 const char *dlm_errmsg(enum dlm_status err);
0067 /* for pretty-printing dlm_status error names */
0068 const char *dlm_errname(enum dlm_status err);
0069
0070 /* Eventually the DLM will use standard errno values, but in the
0071  * meantime this lets us track dlm errors as they bubble up. When we
0072  * bring its error reporting into line with the rest of the stack,
0073  * these can just be replaced with calls to mlog_errno. */
0074 #define dlm_error(st) do {                      \
0075     if ((st) != DLM_RECOVERING &&                   \
0076         (st) != DLM_MIGRATING &&                    \
0077         (st) != DLM_FORWARD)                    \
0078         mlog(ML_ERROR, "dlm status = %s\n", dlm_errname((st))); \
0079 } while (0)
0080
0081 #define DLM_LKSB_UNUSED1           0x01
0082 #define DLM_LKSB_PUT_LVB           0x02
0083 #define DLM_LKSB_GET_LVB           0x04
0084 #define DLM_LKSB_UNUSED2           0x08
0085 #define DLM_LKSB_UNUSED3           0x10
0086 #define DLM_LKSB_UNUSED4           0x20
0087 #define DLM_LKSB_UNUSED5           0x40
0088 #define DLM_LKSB_UNUSED6           0x80
0089
0090 #define DLM_LVB_LEN  64
0091
0092 /* Callers are only allowed access to the lvb and status members of
0093  * this struct. */
0094 struct dlm_lockstatus {
0095     enum dlm_status status;
0096     u32 flags;
0097     struct dlm_lock *lockid;
0098     char lvb[DLM_LVB_LEN];
0099 };
0100
0101 /* Valid lock modes. */
0102 #define LKM_IVMODE      (-1)            /* invalid mode */
0103 #define LKM_NLMODE      0               /* null lock */
0104 #define LKM_CRMODE      1               /* concurrent read    unsupported */
0105 #define LKM_CWMODE      2               /* concurrent write   unsupported */
0106 #define LKM_PRMODE      3               /* protected read */
0107 #define LKM_PWMODE      4               /* protected write    unsupported */
0108 #define LKM_EXMODE      5               /* exclusive */
0109 #define LKM_MAXMODE     5
0110 #define LKM_MODEMASK    0xff
0111
0112 /* Flags passed to dlmlock and dlmunlock:
0113  * reserved: flags used by the "real" dlm
0114  * only a few are supported by this dlm
0115  * (U) = unsupported by ocfs2 dlm */
0116 #define LKM_ORPHAN       0x00000010  /* this lock is orphanable (U) */
0117 #define LKM_PARENTABLE   0x00000020  /* this lock was orphaned (U) */
0118 #define LKM_BLOCK        0x00000040  /* blocking lock request (U) */
0119 #define LKM_LOCAL        0x00000080  /* local lock request */
0120 #define LKM_VALBLK       0x00000100  /* lock value block request */
0121 #define LKM_NOQUEUE      0x00000200  /* non blocking request */
0122 #define LKM_CONVERT      0x00000400  /* conversion request */
0123 #define LKM_NODLCKWT     0x00000800  /* this lock wont deadlock (U) */
0124 #define LKM_UNLOCK       0x00001000  /* deallocate this lock */
0125 #define LKM_CANCEL       0x00002000  /* cancel conversion request */
0126 #define LKM_DEQALL       0x00004000  /* remove all locks held by proc (U) */
0127 #define LKM_INVVALBLK    0x00008000  /* invalidate lock value block */
0128 #define LKM_SYNCSTS      0x00010000  /* return synchronous status if poss (U) */
0129 #define LKM_TIMEOUT      0x00020000  /* lock request contains timeout (U) */
0130 #define LKM_SNGLDLCK     0x00040000  /* request can self-deadlock (U) */
0131 #define LKM_FINDLOCAL    0x00080000  /* find local lock request (U) */
0132 #define LKM_PROC_OWNED   0x00100000  /* owned by process, not group (U) */
0133 #define LKM_XID          0x00200000  /* use transaction id for deadlock (U) */
0134 #define LKM_XID_CONFLICT 0x00400000  /* do not allow lock inheritance (U) */
0135 #define LKM_FORCE        0x00800000  /* force unlock flag */
0136 #define LKM_REVVALBLK    0x01000000  /* temporary solution: re-validate
0137                     lock value block (U) */
0138 /* unused */
0139 #define LKM_UNUSED1      0x00000001  /* unused */
0140 #define LKM_UNUSED2      0x00000002  /* unused */
0141 #define LKM_UNUSED3      0x00000004  /* unused */
0142 #define LKM_UNUSED4      0x00000008  /* unused */
0143 #define LKM_UNUSED5      0x02000000  /* unused */
0144 #define LKM_UNUSED6      0x04000000  /* unused */
0145 #define LKM_UNUSED7      0x08000000  /* unused */
0146
0147 /* ocfs2 extensions: internal only
0148  * should never be used by caller */
0149 #define LKM_MIGRATION    0x10000000  /* extension: lockres is to be migrated
0150                     to another node */
0151 #define LKM_PUT_LVB      0x20000000  /* extension: lvb is being passed
0152                     should be applied to lockres */
0153 #define LKM_GET_LVB      0x40000000  /* extension: lvb should be copied
0154                     from lockres when lock is granted */
0155 #define LKM_RECOVERY     0x80000000  /* extension: flag for recovery lock
0156                     used to avoid recovery rwsem */
0157
0158
0159 typedef void (dlm_astlockfunc_t)(void *);
0160 typedef void (dlm_bastlockfunc_t)(void *, int);
0161 typedef void (dlm_astunlockfunc_t)(void *, enum dlm_status);
0162
0163 enum dlm_status dlmlock(struct dlm_ctxt *dlm,
0164             int mode,
0165             struct dlm_lockstatus *lksb,
0166             int flags,
0167             const char *name,
0168             int namelen,
0169             dlm_astlockfunc_t *ast,
0170             void *data,
0171             dlm_bastlockfunc_t *bast);
0172
0173 enum dlm_status dlmunlock(struct dlm_ctxt *dlm,
0174               struct dlm_lockstatus *lksb,
0175               int flags,
0176               dlm_astunlockfunc_t *unlockast,
0177               void *data);
0178
0179 struct dlm_protocol_version {
0180     u8 pv_major;
0181     u8 pv_minor;
0182 };
0183 struct dlm_ctxt * dlm_register_domain(const char *domain, u32 key,
0184                       struct dlm_protocol_version *fs_proto);
0185
0186 void dlm_unregister_domain(struct dlm_ctxt *dlm);
0187
0188 void dlm_print_one_lock(struct dlm_lock *lockid);
0189
0190 typedef void (dlm_eviction_func)(int, void *);
0191 struct dlm_eviction_cb {
0192     struct list_head        ec_item;
0193     dlm_eviction_func       *ec_func;
0194     void                    *ec_data;
0195 };
0196 void dlm_setup_eviction_cb(struct dlm_eviction_cb *cb,
0197                dlm_eviction_func *f,
0198                void *data);
0199 void dlm_register_eviction_cb(struct dlm_ctxt *dlm,
0200                   struct dlm_eviction_cb *cb);
0201 void dlm_unregister_eviction_cb(struct dlm_eviction_cb *cb);
0202
0203 #endif /* DLMAPI_H */