[PATCH] OCFS2: The Second Oracle Cluster Filesystem

A distributed lock manager built with the cluster file system use case
in mind. The OCFS2 dlm exposes a VMS style API, though things have
been simplified internally. The only lock levels implemented currently
are NLMODE, PRMODE and EXMODE.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Kurt Hackel <kurt.hackel@oracle.com>

1 files changed, 214 insertions, 0 deletions

diff --git a/fs/ocfs2/dlm/dlmapi.h b/fs/ocfs2/dlm/dlmapi.h
new file mode 100644
index 000000000000..53652f51c0e1
--- /dev/null
+++ b/fs/ocfs2/dlm/dlmapi.h
@@ -0,0 +1,214 @@
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * dlmapi.h
+ *
+ * externally exported dlm interfaces
+ *
+ * Copyright (C) 2004 Oracle.  All rights reserved.
+ *
+ * This program 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 of the License, or (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ *
+ */
+
+#ifndef DLMAPI_H
+#define DLMAPI_H
+
+struct dlm_lock;
+struct dlm_ctxt;
+
+/* NOTE: changes made to this enum should be reflected in dlmdebug.c */
+enum dlm_status {
+        DLM_NORMAL = 0,           /*  0: request in progress */
+        DLM_GRANTED,              /*  1: request granted */
+        DLM_DENIED,               /*  2: request denied */
+        DLM_DENIED_NOLOCKS,       /*  3: request denied, out of system resources */
+        DLM_WORKING,              /*  4: async request in progress */
+        DLM_BLOCKED,              /*  5: lock request blocked */
+        DLM_BLOCKED_ORPHAN,       /*  6: lock request blocked by a orphan lock*/
+        DLM_DENIED_GRACE_PERIOD,  /*  7: topological change in progress */
+        DLM_SYSERR,               /*  8: system error */
+        DLM_NOSUPPORT,            /*  9: unsupported */
+        DLM_CANCELGRANT,          /* 10: can't cancel convert: already granted */
+        DLM_IVLOCKID,             /* 11: bad lockid */
+        DLM_SYNC,                 /* 12: synchronous request granted */
+        DLM_BADTYPE,              /* 13: bad resource type */
+        DLM_BADRESOURCE,          /* 14: bad resource handle */
+        DLM_MAXHANDLES,           /* 15: no more resource handles */
+        DLM_NOCLINFO,             /* 16: can't contact cluster manager */
+        DLM_NOLOCKMGR,            /* 17: can't contact lock manager */
+        DLM_NOPURGED,             /* 18: can't contact purge daemon */
+        DLM_BADARGS,              /* 19: bad api args */
+        DLM_VOID,                 /* 20: no status */
+        DLM_NOTQUEUED,            /* 21: NOQUEUE was specified and request failed */
+        DLM_IVBUFLEN,             /* 22: invalid resource name length */
+        DLM_CVTUNGRANT,           /* 23: attempted to convert ungranted lock */
+        DLM_BADPARAM,             /* 24: invalid lock mode specified */
+        DLM_VALNOTVALID,          /* 25: value block has been invalidated */
+        DLM_REJECTED,             /* 26: request rejected, unrecognized client */
+        DLM_ABORT,                /* 27: blocked lock request cancelled */
+        DLM_CANCEL,               /* 28: conversion request cancelled */
+        DLM_IVRESHANDLE,          /* 29: invalid resource handle */
+        DLM_DEADLOCK,             /* 30: deadlock recovery refused this request */
+        DLM_DENIED_NOASTS,        /* 31: failed to allocate AST */
+        DLM_FORWARD,              /* 32: request must wait for primary's response */
+        DLM_TIMEOUT,              /* 33: timeout value for lock has expired */
+        DLM_IVGROUPID,            /* 34: invalid group specification */
+        DLM_VERS_CONFLICT,        /* 35: version conflicts prevent request handling */
+        DLM_BAD_DEVICE_PATH,      /* 36: Locks device does not exist or path wrong */
+        DLM_NO_DEVICE_PERMISSION, /* 37: Client has insufficient pers for device */
+        DLM_NO_CONTROL_DEVICE,    /* 38: Cannot set options on opened device */
+
+        DLM_RECOVERING,           /* 39: extension, allows caller to fail a lock
+                                     request if it is being recovered */
+        DLM_MIGRATING,            /* 40: extension, allows caller to fail a lock
+                                     request if it is being migrated */
+        DLM_MAXSTATS,             /* 41: upper limit for return code validation */
+};
+
+/* for pretty-printing dlm_status error messages */
+const char *dlm_errmsg(enum dlm_status err);
+/* for pretty-printing dlm_status error names */
+const char *dlm_errname(enum dlm_status err);
+
+/* Eventually the DLM will use standard errno values, but in the
+ * meantime this lets us track dlm errors as they bubble up. When we
+ * bring its error reporting into line with the rest of the stack,
+ * these can just be replaced with calls to mlog_errno. */
+#define dlm_error(st) do {                                              \
+        if ((st) != DLM_RECOVERING &&                                   \
+            (st) != DLM_MIGRATING &&                                    \
+            (st) != DLM_FORWARD)                                        \
+                mlog(ML_ERROR, "dlm status = %s\n", dlm_errname((st))); \
+} while (0)
+
+#define DLM_LKSB_UNUSED1           0x01  
+#define DLM_LKSB_PUT_LVB           0x02
+#define DLM_LKSB_GET_LVB           0x04
+#define DLM_LKSB_UNUSED2           0x08
+#define DLM_LKSB_UNUSED3           0x10
+#define DLM_LKSB_UNUSED4           0x20
+#define DLM_LKSB_UNUSED5           0x40
+#define DLM_LKSB_UNUSED6           0x80
+
+#define DLM_LVB_LEN  64
+
+/* Callers are only allowed access to the lvb and status members of
+ * this struct. */
+struct dlm_lockstatus {
+        enum dlm_status status;
+        u32 flags;
+        struct dlm_lock *lockid;
+        char lvb[DLM_LVB_LEN];
+};
+
+/* Valid lock modes. */
+#define LKM_IVMODE      (-1)            /* invalid mode */
+#define LKM_NLMODE      0               /* null lock */
+#define LKM_CRMODE      1               /* concurrent read    unsupported */
+#define LKM_CWMODE      2               /* concurrent write   unsupported */
+#define LKM_PRMODE      3               /* protected read */
+#define LKM_PWMODE      4               /* protected write    unsupported */
+#define LKM_EXMODE      5               /* exclusive */
+#define LKM_MAXMODE     5
+#define LKM_MODEMASK    0xff
+
+/* Flags passed to dlmlock and dlmunlock:
+ * reserved: flags used by the "real" dlm
+ * only a few are supported by this dlm
+ * (U) = unsupported by ocfs2 dlm */
+#define LKM_ORPHAN       0x00000010  /* this lock is orphanable (U) */
+#define LKM_PARENTABLE   0x00000020  /* this lock was orphaned (U) */
+#define LKM_BLOCK        0x00000040  /* blocking lock request (U) */
+#define LKM_LOCAL        0x00000080  /* local lock request */
+#define LKM_VALBLK       0x00000100  /* lock value block request */
+#define LKM_NOQUEUE      0x00000200  /* non blocking request */
+#define LKM_CONVERT      0x00000400  /* conversion request */
+#define LKM_NODLCKWT     0x00000800  /* this lock wont deadlock (U) */
+#define LKM_UNLOCK       0x00001000  /* deallocate this lock */
+#define LKM_CANCEL       0x00002000  /* cancel conversion request */
+#define LKM_DEQALL       0x00004000  /* remove all locks held by proc (U) */
+#define LKM_INVVALBLK    0x00008000  /* invalidate lock value block */
+#define LKM_SYNCSTS      0x00010000  /* return synchronous status if poss (U) */
+#define LKM_TIMEOUT      0x00020000  /* lock request contains timeout (U) */
+#define LKM_SNGLDLCK     0x00040000  /* request can self-deadlock (U) */
+#define LKM_FINDLOCAL    0x00080000  /* find local lock request (U) */
+#define LKM_PROC_OWNED   0x00100000  /* owned by process, not group (U) */
+#define LKM_XID          0x00200000  /* use transaction id for deadlock (U) */
+#define LKM_XID_CONFLICT 0x00400000  /* do not allow lock inheritance (U) */
+#define LKM_FORCE        0x00800000  /* force unlock flag */
+#define LKM_REVVALBLK    0x01000000  /* temporary solution: re-validate
+                                        lock value block (U) */
+/* unused */
+#define LKM_UNUSED1      0x00000001  /* unused */
+#define LKM_UNUSED2      0x00000002  /* unused */
+#define LKM_UNUSED3      0x00000004  /* unused */
+#define LKM_UNUSED4      0x00000008  /* unused */
+#define LKM_UNUSED5      0x02000000  /* unused */
+#define LKM_UNUSED6      0x04000000  /* unused */
+#define LKM_UNUSED7      0x08000000  /* unused */
+
+/* ocfs2 extensions: internal only
+ * should never be used by caller */
+#define LKM_MIGRATION    0x10000000  /* extension: lockres is to be migrated
+                                        to another node */
+#define LKM_PUT_LVB      0x20000000  /* extension: lvb is being passed
+                                        should be applied to lockres */
+#define LKM_GET_LVB      0x40000000  /* extension: lvb should be copied
+                                        from lockres when lock is granted */
+#define LKM_RECOVERY     0x80000000  /* extension: flag for recovery lock
+                                        used to avoid recovery rwsem */
+
+
+typedef void (dlm_astlockfunc_t)(void *);
+typedef void (dlm_bastlockfunc_t)(void *, int);
+typedef void (dlm_astunlockfunc_t)(void *, enum dlm_status);
+
+enum dlm_status dlmlock(struct dlm_ctxt *dlm,
+                        int mode,
+                        struct dlm_lockstatus *lksb,
+                        int flags,
+                        const char *name,
+                        dlm_astlockfunc_t *ast,
+                        void *data,
+                        dlm_bastlockfunc_t *bast);
+
+enum dlm_status dlmunlock(struct dlm_ctxt *dlm,
+                          struct dlm_lockstatus *lksb,
+                          int flags,
+                          dlm_astunlockfunc_t *unlockast,
+                          void *data);
+
+struct dlm_ctxt * dlm_register_domain(const char *domain, u32 key);
+
+void dlm_unregister_domain(struct dlm_ctxt *dlm);
+
+void dlm_print_one_lock(struct dlm_lock *lockid);
+
+typedef void (dlm_eviction_func)(int, void *);
+struct dlm_eviction_cb {
+        struct list_head        ec_item;
+        dlm_eviction_func       *ec_func;
+        void                    *ec_data;
+};
+void dlm_setup_eviction_cb(struct dlm_eviction_cb *cb,
+                           dlm_eviction_func *f,
+                           void *data);
+void dlm_register_eviction_cb(struct dlm_ctxt *dlm,
+                              struct dlm_eviction_cb *cb);
+void dlm_unregister_eviction_cb(struct dlm_eviction_cb *cb);
+
+#endif /* DLMAPI_H */