xref: /linux/include/uapi/linux/dlmconstants.h (revision 1ac731c529cd4d6adbce134754b51ff7d822b145)
1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 /******************************************************************************
3 *******************************************************************************
4 **
5 **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
6 **  Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
7 **
8 **  This copyrighted material is made available to anyone wishing to use,
9 **  modify, copy, or redistribute it subject to the terms and conditions
10 **  of the GNU General Public License v.2.
11 **
12 *******************************************************************************
13 ******************************************************************************/
14 
15 #ifndef __DLMCONSTANTS_DOT_H__
16 #define __DLMCONSTANTS_DOT_H__
17 
18 /*
19  * Constants used by DLM interface.
20  */
21 
22 #define DLM_LOCKSPACE_LEN       64
23 #define DLM_RESNAME_MAXLEN      64
24 
25 
26 /*
27  * Lock Modes
28  */
29 
30 #define DLM_LOCK_IV		(-1)	/* invalid */
31 #define DLM_LOCK_NL		0	/* null */
32 #define DLM_LOCK_CR		1	/* concurrent read */
33 #define DLM_LOCK_CW		2	/* concurrent write */
34 #define DLM_LOCK_PR		3	/* protected read */
35 #define DLM_LOCK_PW		4	/* protected write */
36 #define DLM_LOCK_EX		5	/* exclusive */
37 
38 
39 /*
40  * Flags to dlm_lock
41  *
42  * DLM_LKF_NOQUEUE
43  *
44  * Do not queue the lock request on the wait queue if it cannot be granted
45  * immediately.  If the lock cannot be granted because of this flag, DLM will
46  * either return -EAGAIN from the dlm_lock call or will return 0 from
47  * dlm_lock and -EAGAIN in the lock status block when the AST is executed.
48  *
49  * DLM_LKF_CANCEL
50  *
51  * Used to cancel a pending lock request or conversion.  A converting lock is
52  * returned to its previously granted mode.
53  *
54  * DLM_LKF_CONVERT
55  *
56  * Indicates a lock conversion request.  For conversions the name and namelen
57  * are ignored and the lock ID in the LKSB is used to identify the lock.
58  *
59  * DLM_LKF_VALBLK
60  *
61  * Requests DLM to return the current contents of the lock value block in the
62  * lock status block.  When this flag is set in a lock conversion from PW or EX
63  * modes, DLM assigns the value specified in the lock status block to the lock
64  * value block of the lock resource.  The LVB is a DLM_LVB_LEN size array
65  * containing application-specific information.
66  *
67  * DLM_LKF_QUECVT
68  *
69  * Force a conversion request to be queued, even if it is compatible with
70  * the granted modes of other locks on the same resource.
71  *
72  * DLM_LKF_IVVALBLK
73  *
74  * Invalidate the lock value block.
75  *
76  * DLM_LKF_CONVDEADLK
77  *
78  * Allows the dlm to resolve conversion deadlocks internally by demoting the
79  * granted mode of a converting lock to NL.  The DLM_SBF_DEMOTED flag is
80  * returned for a conversion that's been effected by this.
81  *
82  * DLM_LKF_PERSISTENT
83  *
84  * Only relevant to locks originating in userspace.  A persistent lock will not
85  * be removed if the process holding the lock exits.
86  *
87  * DLM_LKF_NODLCKWT
88  *
89  * Do not cancel the lock if it gets into conversion deadlock.
90  *
91  * DLM_LKF_NODLCKBLK
92  *
93  * net yet implemented
94  *
95  * DLM_LKF_EXPEDITE
96  *
97  * Used only with new requests for NL mode locks.  Tells the lock manager
98  * to grant the lock, ignoring other locks in convert and wait queues.
99  *
100  * DLM_LKF_NOQUEUEBAST
101  *
102  * Send blocking AST's before returning -EAGAIN to the caller.  It is only
103  * used along with the NOQUEUE flag.  Blocking AST's are not sent for failed
104  * NOQUEUE requests otherwise.
105  *
106  * DLM_LKF_HEADQUE
107  *
108  * Add a lock to the head of the convert or wait queue rather than the tail.
109  *
110  * DLM_LKF_NOORDER
111  *
112  * Disregard the standard grant order rules and grant a lock as soon as it
113  * is compatible with other granted locks.
114  *
115  * DLM_LKF_ORPHAN
116  *
117  * Acquire an orphan lock.
118  *
119  * DLM_LKF_ALTPR
120  *
121  * If the requested mode cannot be granted immediately, try to grant the lock
122  * in PR mode instead.  If this alternate mode is granted instead of the
123  * requested mode, DLM_SBF_ALTMODE is returned in the lksb.
124  *
125  * DLM_LKF_ALTCW
126  *
127  * The same as ALTPR, but the alternate mode is CW.
128  *
129  * DLM_LKF_FORCEUNLOCK
130  *
131  * Unlock the lock even if it is converting or waiting or has sublocks.
132  * Only really for use by the userland device.c code.
133  *
134  * DLM_LKF_TIMEOUT
135  *
136  * This value is deprecated and reserved. DO NOT USE!
137  *
138  */
139 
140 #define DLM_LKF_NOQUEUE		0x00000001
141 #define DLM_LKF_CANCEL		0x00000002
142 #define DLM_LKF_CONVERT		0x00000004
143 #define DLM_LKF_VALBLK		0x00000008
144 #define DLM_LKF_QUECVT		0x00000010
145 #define DLM_LKF_IVVALBLK	0x00000020
146 #define DLM_LKF_CONVDEADLK	0x00000040
147 #define DLM_LKF_PERSISTENT	0x00000080
148 #define DLM_LKF_NODLCKWT	0x00000100
149 #define DLM_LKF_NODLCKBLK	0x00000200
150 #define DLM_LKF_EXPEDITE	0x00000400
151 #define DLM_LKF_NOQUEUEBAST	0x00000800
152 #define DLM_LKF_HEADQUE		0x00001000
153 #define DLM_LKF_NOORDER		0x00002000
154 #define DLM_LKF_ORPHAN		0x00004000
155 #define DLM_LKF_ALTPR		0x00008000
156 #define DLM_LKF_ALTCW		0x00010000
157 #define DLM_LKF_FORCEUNLOCK	0x00020000
158 #define DLM_LKF_TIMEOUT		0x00040000
159 
160 /*
161  * Some return codes that are not in errno.h
162  */
163 
164 #define DLM_ECANCEL		0x10001
165 #define DLM_EUNLOCK		0x10002
166 
167 #endif  /* __DLMCONSTANTS_DOT_H__ */
168