1 /******************************************************************************
2 *******************************************************************************
4 ** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
5 ** Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
7 ** This copyrighted material is made available to anyone wishing to use,
8 ** modify, copy, or redistribute it subject to the terms and conditions
9 ** of the GNU General Public License v.2.
11 *******************************************************************************
12 ******************************************************************************/
18 * Interface to Distributed Lock Manager (DLM)
19 * routines and structures to use DLM lockspaces
22 /* Lock levels and flags are here */
23 #include <linux/dlmconstants.h>
25 typedef void dlm_lockspace_t;
30 * Use this structure to specify the contents of the lock value block. For a
31 * conversion request, this structure is used to specify the lock ID of the
32 * lock. DLM writes the status of the lock request and the lock ID assigned
33 * to the request in the lock status block.
35 * sb_lkid: the returned lock ID. It is set on new (non-conversion) requests.
36 * It is available when dlm_lock returns.
38 * sb_lvbptr: saves or returns the contents of the lock's LVB according to rules
39 * shown for the DLM_LKF_VALBLK flag.
41 * sb_flags: DLM_SBF_DEMOTED is returned if in the process of promoting a lock,
42 * it was first demoted to NL to avoid conversion deadlock.
43 * DLM_SBF_VALNOTVALID is returned if the resource's LVB is marked invalid.
45 * sb_status: the returned status of the lock request set prior to AST
46 * execution. Possible return values:
48 * 0 if lock request was successful
49 * -EAGAIN if request would block and is flagged DLM_LKF_NOQUEUE
50 * -ENOMEM if there is no memory to process request
51 * -EINVAL if there are invalid parameters
52 * -DLM_EUNLOCK if unlock request was successful
53 * -DLM_ECANCEL if a cancel completed successfully
56 #define DLM_SBF_DEMOTED 0x01
57 #define DLM_SBF_VALNOTVALID 0x02
58 #define DLM_SBF_ALTMODE 0x04
67 #define DLM_LSFL_NODIR 0x00000001
68 #define DLM_LSFL_TIMEWARN 0x00000002
69 #define DLM_LSFL_FS 0x00000004
76 * Starts a lockspace with the given name. If the named lockspace exists in
77 * the cluster, the calling node joins it.
80 int dlm_new_lockspace(char *name, int namelen, dlm_lockspace_t **lockspace,
81 uint32_t flags, int lvblen);
84 * dlm_release_lockspace
89 int dlm_release_lockspace(dlm_lockspace_t *lockspace, int force);
94 * Make an asyncronous request to acquire or convert a lock on a named
97 * lockspace: context for the request
98 * mode: the requested mode of the lock (DLM_LOCK_)
99 * lksb: lock status block for input and async return values
100 * flags: input flags (DLM_LKF_)
101 * name: name of the resource to lock, can be binary
102 * namelen: the length in bytes of the resource name (MAX_RESNAME_LEN)
103 * parent: the lock ID of a parent lock or 0 if none
104 * lockast: function DLM executes when it completes processing the request
105 * astarg: argument passed to lockast and bast functions
106 * bast: function DLM executes when this lock later blocks another request
109 * 0 if request is successfully queued for processing
110 * -EINVAL if any input parameters are invalid
111 * -EAGAIN if request would block and is flagged DLM_LKF_NOQUEUE
112 * -ENOMEM if there is no memory to process request
113 * -ENOTCONN if there is a communication error
115 * If the call to dlm_lock returns an error then the operation has failed and
116 * the AST routine will not be called. If dlm_lock returns 0 it is still
117 * possible that the lock operation will fail. The AST routine will be called
118 * when the locking is complete and the status is returned in the lksb.
120 * If the AST routines or parameter are passed to a conversion operation then
121 * they will overwrite those values that were passed to a previous dlm_lock
124 * AST routines should not block (at least not for long), but may make
125 * any locking calls they please.
128 int dlm_lock(dlm_lockspace_t *lockspace,
130 struct dlm_lksb *lksb,
133 unsigned int namelen,
134 uint32_t parent_lkid,
135 void (*lockast) (void *astarg),
137 void (*bast) (void *astarg, int mode));
142 * Asynchronously release a lock on a resource. The AST routine is called
143 * when the resource is successfully unlocked.
145 * lockspace: context for the request
146 * lkid: the lock ID as returned in the lksb
147 * flags: input flags (DLM_LKF_)
148 * lksb: if NULL the lksb parameter passed to last lock request is used
149 * astarg: the arg used with the completion ast for the unlock
152 * 0 if request is successfully queued for processing
153 * -EINVAL if any input parameters are invalid
154 * -ENOTEMPTY if the lock still has sublocks
155 * -EBUSY if the lock is waiting for a remote lock operation
156 * -ENOTCONN if there is a communication error
159 int dlm_unlock(dlm_lockspace_t *lockspace,
162 struct dlm_lksb *lksb,
165 #endif /* __KERNEL__ */
167 #endif /* __DLM_DOT_H__ */