2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved.
5 * This copyrighted material is made available to anyone wishing to use,
6 * modify, copy, or redistribute it subject to the terms and conditions
7 * of the GNU General Public License version 2.
10 #include <linux/module.h>
11 #include <linux/slab.h>
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/types.h>
16 #include <linux/smp_lock.h>
17 #include <linux/lm_interface.h>
19 struct nolock_lockspace {
20 unsigned int nl_lvb_size;
23 static const struct lm_lockops nolock_ops;
25 static int nolock_mount(char *table_name, char *host_data,
26 lm_callback_t cb, void *cb_data,
27 unsigned int min_lvb_size, int flags,
28 struct lm_lockstruct *lockstruct,
29 struct kobject *fskobj)
33 struct nolock_lockspace *nl;
35 c = strstr(host_data, "jid=");
40 sscanf(c, "%u", &jid);
43 nl = kzalloc(sizeof(struct nolock_lockspace), GFP_KERNEL);
47 nl->nl_lvb_size = min_lvb_size;
49 lockstruct->ls_jid = jid;
50 lockstruct->ls_first = 1;
51 lockstruct->ls_lvb_size = min_lvb_size;
52 lockstruct->ls_lockspace = nl;
53 lockstruct->ls_ops = &nolock_ops;
54 lockstruct->ls_flags = LM_LSFLAG_LOCAL;
59 static void nolock_others_may_mount(void *lockspace)
63 static void nolock_unmount(void *lockspace)
65 struct nolock_lockspace *nl = lockspace;
69 static void nolock_withdraw(void *lockspace)
74 * nolock_get_lock - get a lm_lock_t given a descripton of the lock
75 * @lockspace: the lockspace the lock lives in
76 * @name: the name of the lock
77 * @lockp: return the lm_lock_t here
79 * Returns: 0 on success, -EXXX on failure
82 static int nolock_get_lock(void *lockspace, struct lm_lockname *name,
90 * nolock_put_lock - get rid of a lock structure
91 * @lock: the lock to throw away
95 static void nolock_put_lock(void *lock)
100 * nolock_lock - acquire a lock
101 * @lock: the lock to manipulate
102 * @cur_state: the current state
103 * @req_state: the requested state
104 * @flags: modifier flags
106 * Returns: A bitmap of LM_OUT_*
109 static unsigned int nolock_lock(void *lock, unsigned int cur_state,
110 unsigned int req_state, unsigned int flags)
112 return req_state | LM_OUT_CACHEABLE;
116 * nolock_unlock - unlock a lock
117 * @lock: the lock to manipulate
118 * @cur_state: the current state
123 static unsigned int nolock_unlock(void *lock, unsigned int cur_state)
128 static void nolock_cancel(void *lock)
133 * nolock_hold_lvb - hold on to a lock value block
134 * @lock: the lock the LVB is associated with
135 * @lvbp: return the lm_lvb_t here
137 * Returns: 0 on success, -EXXX on failure
140 static int nolock_hold_lvb(void *lock, char **lvbp)
142 struct nolock_lockspace *nl = lock;
145 *lvbp = kzalloc(nl->nl_lvb_size, GFP_KERNEL);
153 * nolock_unhold_lvb - release a LVB
154 * @lock: the lock the LVB is associated with
155 * @lvb: the lock value block
159 static void nolock_unhold_lvb(void *lock, char *lvb)
164 static int nolock_plock_get(void *lockspace, struct lm_lockname *name,
165 struct file *file, struct file_lock *fl)
167 struct file_lock tmp;
170 ret = posix_test_lock(file, fl, &tmp);
171 fl->fl_type = F_UNLCK;
173 memcpy(fl, &tmp, sizeof(struct file_lock));
178 static int nolock_plock(void *lockspace, struct lm_lockname *name,
179 struct file *file, int cmd, struct file_lock *fl)
182 error = posix_lock_file_wait(file, fl);
186 static int nolock_punlock(void *lockspace, struct lm_lockname *name,
187 struct file *file, struct file_lock *fl)
190 error = posix_lock_file_wait(file, fl);
194 static void nolock_recovery_done(void *lockspace, unsigned int jid,
195 unsigned int message)
199 static const struct lm_lockops nolock_ops = {
200 .lm_proto_name = "lock_nolock",
201 .lm_mount = nolock_mount,
202 .lm_others_may_mount = nolock_others_may_mount,
203 .lm_unmount = nolock_unmount,
204 .lm_withdraw = nolock_withdraw,
205 .lm_get_lock = nolock_get_lock,
206 .lm_put_lock = nolock_put_lock,
207 .lm_lock = nolock_lock,
208 .lm_unlock = nolock_unlock,
209 .lm_cancel = nolock_cancel,
210 .lm_hold_lvb = nolock_hold_lvb,
211 .lm_unhold_lvb = nolock_unhold_lvb,
212 .lm_plock_get = nolock_plock_get,
213 .lm_plock = nolock_plock,
214 .lm_punlock = nolock_punlock,
215 .lm_recovery_done = nolock_recovery_done,
216 .lm_owner = THIS_MODULE,
219 static int __init init_nolock(void)
223 error = gfs2_register_lockproto(&nolock_ops);
226 "lock_nolock: can't register protocol: %d\n", error);
231 "Lock_Nolock (built %s %s) installed\n", __DATE__, __TIME__);
235 static void __exit exit_nolock(void)
237 gfs2_unregister_lockproto(&nolock_ops);
240 module_init(init_nolock);
241 module_exit(exit_nolock);
243 MODULE_DESCRIPTION("GFS Nolock Locking Module");
244 MODULE_AUTHOR("Red Hat, Inc.");
245 MODULE_LICENSE("GPL");