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/******************************************************************************
*******************************************************************************
**
** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
** Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
**
** This copyrighted material is made available to anyone wishing to use,
** modify, copy, or redistribute it subject to the terms and conditions
** of the GNU General Public License v.2.
**
*******************************************************************************
******************************************************************************/
#ifndef __DLM_DOT_H__
#define __DLM_DOT_H__
/*
* Interface to Distributed Lock Manager (DLM)
* routines and structures to use DLM lockspaces
*/
/*
* Lock Modes
*/
#define DLM_LOCK_IV -1 /* invalid */
#define DLM_LOCK_NL 0 /* null */
#define DLM_LOCK_CR 1 /* concurrent read */
#define DLM_LOCK_CW 2 /* concurrent write */
#define DLM_LOCK_PR 3 /* protected read */
#define DLM_LOCK_PW 4 /* protected write */
#define DLM_LOCK_EX 5 /* exclusive */
/*
* Maximum size in bytes of a dlm_lock name
*/
#define DLM_RESNAME_MAXLEN 64
/*
* Flags to dlm_lock
*
* DLM_LKF_NOQUEUE
*
* Do not queue the lock request on the wait queue if it cannot be granted
* immediately. If the lock cannot be granted because of this flag, DLM will
* either return -EAGAIN from the dlm_lock call or will return 0 from
* dlm_lock and -EAGAIN in the lock status block when the AST is executed.
*
* DLM_LKF_CANCEL
*
* Used to cancel a pending lock request or conversion. A converting lock is
* returned to its previously granted mode.
*
* DLM_LKF_CONVERT
*
* Indicates a lock conversion request. For conversions the name and namelen
* are ignored and the lock ID in the LKSB is used to identify the lock.
*
* DLM_LKF_VALBLK
*
* Requests DLM to return the current contents of the lock value block in the
* lock status block. When this flag is set in a lock conversion from PW or EX
* modes, DLM assigns the value specified in the lock status block to the lock
* value block of the lock resource. The LVB is a DLM_LVB_LEN size array
* containing application-specific information.
*
* DLM_LKF_QUECVT
*
* Force a conversion request to be queued, even if it is compatible with
* the granted modes of other locks on the same resource.
*
* DLM_LKF_IVVALBLK
*
* Invalidate the lock value block.
*
* DLM_LKF_CONVDEADLK
*
* Allows the dlm to resolve conversion deadlocks internally by demoting the
* granted mode of a converting lock to NL. The DLM_SBF_DEMOTED flag is
* returned for a conversion that's been effected by this.
*
* DLM_LKF_PERSISTENT
*
* Only relevant to locks originating in userspace. A persistent lock will not
* be removed if the process holding the lock exits.
*
* DLM_LKF_NODLCKWT
*
* Do not cancel the lock if it gets into conversion deadlock.
* Exclude this lock from being monitored due to DLM_LSFL_TIMEWARN.
*
* DLM_LKF_NODLCKBLK
*
* net yet implemented
*
* DLM_LKF_EXPEDITE
*
* Used only with new requests for NL mode locks. Tells the lock manager
* to grant the lock, ignoring other locks in convert and wait queues.
*
* DLM_LKF_NOQUEUEBAST
*
* Send blocking AST's before returning -EAGAIN to the caller. It is only
* used along with the NOQUEUE flag. Blocking AST's are not sent for failed
* NOQUEUE requests otherwise.
*
* DLM_LKF_HEADQUE
*
* Add a lock to the head of the convert or wait queue rather than the tail.
*
* DLM_LKF_NOORDER
*
* Disregard the standard grant order rules and grant a lock as soon as it
* is compatible with other granted locks.
*
* DLM_LKF_ORPHAN
*
* not yet implemented
*
* DLM_LKF_ALTPR
*
* If the requested mode cannot be granted immediately, try to grant the lock
* in PR mode instead. If this alternate mode is granted instead of the
* requested mode, DLM_SBF_ALTMODE is returned in the lksb.
*
* DLM_LKF_ALTCW
*
* The same as ALTPR, but the alternate mode is CW.
*
* DLM_LKF_FORCEUNLOCK
*
* Unlock the lock even if it is converting or waiting or has sublocks.
* Only really for use by the userland device.c code.
*
*/
#define DLM_LKF_NOQUEUE 0x00000001
#define DLM_LKF_CANCEL 0x00000002
#define DLM_LKF_CONVERT 0x00000004
#define DLM_LKF_VALBLK 0x00000008
#define DLM_LKF_QUECVT 0x00000010
#define DLM_LKF_IVVALBLK 0x00000020
#define DLM_LKF_CONVDEADLK 0x00000040
#define DLM_LKF_PERSISTENT 0x00000080
#define DLM_LKF_NODLCKWT 0x00000100
#define DLM_LKF_NODLCKBLK 0x00000200
#define DLM_LKF_EXPEDITE 0x00000400
#define DLM_LKF_NOQUEUEBAST 0x00000800
#define DLM_LKF_HEADQUE 0x00001000
#define DLM_LKF_NOORDER 0x00002000
#define DLM_LKF_ORPHAN 0x00004000
#define DLM_LKF_ALTPR 0x00008000
#define DLM_LKF_ALTCW 0x00010000
#define DLM_LKF_FORCEUNLOCK 0x00020000
#define DLM_LKF_TIMEOUT 0x00040000
/*
* Some return codes that are not in errno.h
*/
#define DLM_ECANCEL 0x10001
#define DLM_EUNLOCK 0x10002
typedef void dlm_lockspace_t;
/*
* Lock status block
*
* Use this structure to specify the contents of the lock value block. For a
* conversion request, this structure is used to specify the lock ID of the
* lock. DLM writes the status of the lock request and the lock ID assigned
* to the request in the lock status block.
*
* sb_lkid: the returned lock ID. It is set on new (non-conversion) requests.
* It is available when dlm_lock returns.
*
* sb_lvbptr: saves or returns the contents of the lock's LVB according to rules
* shown for the DLM_LKF_VALBLK flag.
*
* sb_flags: DLM_SBF_DEMOTED is returned if in the process of promoting a lock,
* it was first demoted to NL to avoid conversion deadlock.
* DLM_SBF_VALNOTVALID is returned if the resource's LVB is marked invalid.
*
* sb_status: the returned status of the lock request set prior to AST
* execution. Possible return values:
*
* 0 if lock request was successful
* -EAGAIN if request would block and is flagged DLM_LKF_NOQUEUE
* -ENOMEM if there is no memory to process request
* -EINVAL if there are invalid parameters
* -DLM_EUNLOCK if unlock request was successful
* -DLM_ECANCEL if a cancel completed successfully
*/
#define DLM_SBF_DEMOTED 0x01
#define DLM_SBF_VALNOTVALID 0x02
#define DLM_SBF_ALTMODE 0x04
struct dlm_lksb {
int sb_status;
uint32_t sb_lkid;
char sb_flags;
char * sb_lvbptr;
};
#define DLM_LSFL_NODIR 0x00000001
#define DLM_LSFL_TIMEWARN 0x00000002
#define DLM_LSFL_FS 0x00000004
#endif /* __DLM_DOT_H__ */
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