blob: 284a5ece8d94deb6a2d42cbf47e48fcb125bff9c [file] [log] [blame]
David Teigland869d81d2006-01-17 08:47:12 +00001/*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved.
4 *
5 * This copyrighted material is made available to anyone wishing to use,
6 * modify, copy, or redistribute it subject to the terms and conditions
Steven Whitehousee9fc2aa2006-09-01 11:05:15 -04007 * of the GNU General Public License version 2.
David Teigland869d81d2006-01-17 08:47:12 +00008 */
David Teigland29b79982006-01-16 16:52:38 +00009
10#include <linux/module.h>
11#include <linux/slab.h>
David Teigland29b79982006-01-16 16:52:38 +000012#include <linux/init.h>
13#include <linux/types.h>
14#include <linux/fs.h>
Fabio Massimo Di Nitto7d308592006-09-19 07:56:29 +020015#include <linux/lm_interface.h>
David Teigland29b79982006-01-16 16:52:38 +000016
17struct nolock_lockspace {
18 unsigned int nl_lvb_size;
19};
20
Steven Whitehouse9b47c112006-09-08 10:17:58 -040021static const struct lm_lockops nolock_ops;
David Teigland29b79982006-01-16 16:52:38 +000022
David Teigland29b79982006-01-16 16:52:38 +000023static int nolock_mount(char *table_name, char *host_data,
Steven Whitehouse9b47c112006-09-08 10:17:58 -040024 lm_callback_t cb, void *cb_data,
David Teigland29b79982006-01-16 16:52:38 +000025 unsigned int min_lvb_size, int flags,
David Teigland869d81d2006-01-17 08:47:12 +000026 struct lm_lockstruct *lockstruct,
27 struct kobject *fskobj)
David Teigland29b79982006-01-16 16:52:38 +000028{
29 char *c;
30 unsigned int jid;
31 struct nolock_lockspace *nl;
32
David Teigland29b79982006-01-16 16:52:38 +000033 c = strstr(host_data, "jid=");
34 if (!c)
35 jid = 0;
36 else {
37 c += 4;
38 sscanf(c, "%u", &jid);
39 }
40
Steven Whitehoused92a8d42006-02-27 10:57:14 -050041 nl = kzalloc(sizeof(struct nolock_lockspace), GFP_KERNEL);
David Teigland29b79982006-01-16 16:52:38 +000042 if (!nl)
43 return -ENOMEM;
44
David Teigland29b79982006-01-16 16:52:38 +000045 nl->nl_lvb_size = min_lvb_size;
46
47 lockstruct->ls_jid = jid;
48 lockstruct->ls_first = 1;
49 lockstruct->ls_lvb_size = min_lvb_size;
Steven Whitehouse9b47c112006-09-08 10:17:58 -040050 lockstruct->ls_lockspace = nl;
David Teigland29b79982006-01-16 16:52:38 +000051 lockstruct->ls_ops = &nolock_ops;
52 lockstruct->ls_flags = LM_LSFLAG_LOCAL;
53
54 return 0;
55}
56
Steven Whitehouse9b47c112006-09-08 10:17:58 -040057static void nolock_others_may_mount(void *lockspace)
David Teigland29b79982006-01-16 16:52:38 +000058{
59}
60
Steven Whitehouse9b47c112006-09-08 10:17:58 -040061static void nolock_unmount(void *lockspace)
David Teigland29b79982006-01-16 16:52:38 +000062{
Steven Whitehouse9b47c112006-09-08 10:17:58 -040063 struct nolock_lockspace *nl = lockspace;
David Teigland29b79982006-01-16 16:52:38 +000064 kfree(nl);
65}
66
Steven Whitehouse9b47c112006-09-08 10:17:58 -040067static void nolock_withdraw(void *lockspace)
David Teigland29b79982006-01-16 16:52:38 +000068{
69}
70
71/**
72 * nolock_get_lock - get a lm_lock_t given a descripton of the lock
73 * @lockspace: the lockspace the lock lives in
74 * @name: the name of the lock
75 * @lockp: return the lm_lock_t here
76 *
77 * Returns: 0 on success, -EXXX on failure
78 */
79
Steven Whitehouse9b47c112006-09-08 10:17:58 -040080static int nolock_get_lock(void *lockspace, struct lm_lockname *name,
81 void **lockp)
David Teigland29b79982006-01-16 16:52:38 +000082{
Steven Whitehouse9b47c112006-09-08 10:17:58 -040083 *lockp = lockspace;
David Teigland29b79982006-01-16 16:52:38 +000084 return 0;
85}
86
87/**
88 * nolock_put_lock - get rid of a lock structure
89 * @lock: the lock to throw away
90 *
91 */
92
Steven Whitehouse9b47c112006-09-08 10:17:58 -040093static void nolock_put_lock(void *lock)
David Teigland29b79982006-01-16 16:52:38 +000094{
95}
96
97/**
98 * nolock_lock - acquire a lock
99 * @lock: the lock to manipulate
100 * @cur_state: the current state
101 * @req_state: the requested state
102 * @flags: modifier flags
103 *
104 * Returns: A bitmap of LM_OUT_*
105 */
106
Steven Whitehouse9b47c112006-09-08 10:17:58 -0400107static unsigned int nolock_lock(void *lock, unsigned int cur_state,
David Teigland29b79982006-01-16 16:52:38 +0000108 unsigned int req_state, unsigned int flags)
109{
110 return req_state | LM_OUT_CACHEABLE;
111}
112
113/**
114 * nolock_unlock - unlock a lock
115 * @lock: the lock to manipulate
116 * @cur_state: the current state
117 *
118 * Returns: 0
119 */
120
Steven Whitehouse9b47c112006-09-08 10:17:58 -0400121static unsigned int nolock_unlock(void *lock, unsigned int cur_state)
David Teigland29b79982006-01-16 16:52:38 +0000122{
123 return 0;
124}
125
Steven Whitehouse9b47c112006-09-08 10:17:58 -0400126static void nolock_cancel(void *lock)
David Teigland29b79982006-01-16 16:52:38 +0000127{
128}
129
130/**
131 * nolock_hold_lvb - hold on to a lock value block
132 * @lock: the lock the LVB is associated with
133 * @lvbp: return the lm_lvb_t here
134 *
135 * Returns: 0 on success, -EXXX on failure
136 */
137
Steven Whitehouse9b47c112006-09-08 10:17:58 -0400138static int nolock_hold_lvb(void *lock, char **lvbp)
David Teigland29b79982006-01-16 16:52:38 +0000139{
Steven Whitehouse9b47c112006-09-08 10:17:58 -0400140 struct nolock_lockspace *nl = lock;
David Teigland29b79982006-01-16 16:52:38 +0000141 int error = 0;
142
Josef Bacik16c5f062008-04-09 09:33:41 -0400143 *lvbp = kzalloc(nl->nl_lvb_size, GFP_NOFS);
Steven Whitehoused92a8d42006-02-27 10:57:14 -0500144 if (!*lvbp)
David Teigland29b79982006-01-16 16:52:38 +0000145 error = -ENOMEM;
146
147 return error;
148}
149
150/**
151 * nolock_unhold_lvb - release a LVB
152 * @lock: the lock the LVB is associated with
153 * @lvb: the lock value block
154 *
155 */
156
Steven Whitehouse9b47c112006-09-08 10:17:58 -0400157static void nolock_unhold_lvb(void *lock, char *lvb)
David Teigland29b79982006-01-16 16:52:38 +0000158{
159 kfree(lvb);
160}
161
Steven Whitehouse9b47c112006-09-08 10:17:58 -0400162static int nolock_plock_get(void *lockspace, struct lm_lockname *name,
David Teigland29b79982006-01-16 16:52:38 +0000163 struct file *file, struct file_lock *fl)
164{
Marc Eshel9d6a8c52007-02-21 00:55:18 -0500165 posix_test_lock(file, fl);
David Teigland29b79982006-01-16 16:52:38 +0000166
167 return 0;
168}
169
Steven Whitehouse9b47c112006-09-08 10:17:58 -0400170static int nolock_plock(void *lockspace, struct lm_lockname *name,
David Teigland29b79982006-01-16 16:52:38 +0000171 struct file *file, int cmd, struct file_lock *fl)
172{
173 int error;
David Teigland29b79982006-01-16 16:52:38 +0000174 error = posix_lock_file_wait(file, fl);
David Teigland29b79982006-01-16 16:52:38 +0000175 return error;
176}
177
Steven Whitehouse9b47c112006-09-08 10:17:58 -0400178static int nolock_punlock(void *lockspace, struct lm_lockname *name,
David Teigland29b79982006-01-16 16:52:38 +0000179 struct file *file, struct file_lock *fl)
180{
181 int error;
David Teigland29b79982006-01-16 16:52:38 +0000182 error = posix_lock_file_wait(file, fl);
David Teigland29b79982006-01-16 16:52:38 +0000183 return error;
184}
185
Steven Whitehouse9b47c112006-09-08 10:17:58 -0400186static void nolock_recovery_done(void *lockspace, unsigned int jid,
David Teigland29b79982006-01-16 16:52:38 +0000187 unsigned int message)
188{
189}
190
Steven Whitehouse9b47c112006-09-08 10:17:58 -0400191static const struct lm_lockops nolock_ops = {
David Teigland29b79982006-01-16 16:52:38 +0000192 .lm_proto_name = "lock_nolock",
193 .lm_mount = nolock_mount,
194 .lm_others_may_mount = nolock_others_may_mount,
195 .lm_unmount = nolock_unmount,
196 .lm_withdraw = nolock_withdraw,
197 .lm_get_lock = nolock_get_lock,
198 .lm_put_lock = nolock_put_lock,
199 .lm_lock = nolock_lock,
200 .lm_unlock = nolock_unlock,
201 .lm_cancel = nolock_cancel,
202 .lm_hold_lvb = nolock_hold_lvb,
203 .lm_unhold_lvb = nolock_unhold_lvb,
David Teigland29b79982006-01-16 16:52:38 +0000204 .lm_plock_get = nolock_plock_get,
205 .lm_plock = nolock_plock,
206 .lm_punlock = nolock_punlock,
207 .lm_recovery_done = nolock_recovery_done,
208 .lm_owner = THIS_MODULE,
209};
210
Adrian Bunk08bc2db2006-04-28 10:59:12 -0400211static int __init init_nolock(void)
David Teigland29b79982006-01-16 16:52:38 +0000212{
213 int error;
214
David Teigland3120ec52006-08-04 13:14:50 -0500215 error = gfs2_register_lockproto(&nolock_ops);
David Teigland29b79982006-01-16 16:52:38 +0000216 if (error) {
Steven Whitehousef3828942006-02-27 12:07:05 -0500217 printk(KERN_WARNING
218 "lock_nolock: can't register protocol: %d\n", error);
David Teigland29b79982006-01-16 16:52:38 +0000219 return error;
220 }
221
Steven Whitehousef3828942006-02-27 12:07:05 -0500222 printk(KERN_INFO
223 "Lock_Nolock (built %s %s) installed\n", __DATE__, __TIME__);
David Teigland29b79982006-01-16 16:52:38 +0000224 return 0;
225}
226
Adrian Bunk08bc2db2006-04-28 10:59:12 -0400227static void __exit exit_nolock(void)
David Teigland29b79982006-01-16 16:52:38 +0000228{
David Teigland3120ec52006-08-04 13:14:50 -0500229 gfs2_unregister_lockproto(&nolock_ops);
David Teigland29b79982006-01-16 16:52:38 +0000230}
231
232module_init(init_nolock);
233module_exit(exit_nolock);
234
235MODULE_DESCRIPTION("GFS Nolock Locking Module");
236MODULE_AUTHOR("Red Hat, Inc.");
237MODULE_LICENSE("GPL");
238