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-rw-r--r--fs/gfs2/locking.c314
1 files changed, 0 insertions, 314 deletions
diff --git a/fs/gfs2/locking.c b/fs/gfs2/locking.c
deleted file mode 100644
index d3657bc7938a..000000000000
--- a/fs/gfs2/locking.c
+++ /dev/null
@@ -1,314 +0,0 @@
1/*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2006 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
7 * of the GNU General Public License version 2.
8 */
9
10#include <linux/module.h>
11#include <linux/init.h>
12#include <linux/string.h>
13#include <linux/slab.h>
14#include <linux/wait.h>
15#include <linux/sched.h>
16#include <linux/kmod.h>
17#include <linux/fs.h>
18#include <linux/delay.h>
19#include <linux/lm_interface.h>
20
21struct lmh_wrapper {
22 struct list_head lw_list;
23 const struct lm_lockops *lw_ops;
24};
25
26struct nolock_lockspace {
27 unsigned int nl_lvb_size;
28};
29
30/**
31 * nolock_get_lock - get a lm_lock_t given a descripton of the lock
32 * @lockspace: the lockspace the lock lives in
33 * @name: the name of the lock
34 * @lockp: return the lm_lock_t here
35 *
36 * Returns: 0 on success, -EXXX on failure
37 */
38
39static int nolock_get_lock(void *lockspace, struct lm_lockname *name,
40 void **lockp)
41{
42 *lockp = lockspace;
43 return 0;
44}
45
46/**
47 * nolock_put_lock - get rid of a lock structure
48 * @lock: the lock to throw away
49 *
50 */
51
52static void nolock_put_lock(void *lock)
53{
54}
55
56/**
57 * nolock_hold_lvb - hold on to a lock value block
58 * @lock: the lock the LVB is associated with
59 * @lvbp: return the lm_lvb_t here
60 *
61 * Returns: 0 on success, -EXXX on failure
62 */
63
64static int nolock_hold_lvb(void *lock, char **lvbp)
65{
66 struct nolock_lockspace *nl = lock;
67 int error = 0;
68
69 *lvbp = kzalloc(nl->nl_lvb_size, GFP_KERNEL);
70 if (!*lvbp)
71 error = -ENOMEM;
72
73 return error;
74}
75
76/**
77 * nolock_unhold_lvb - release a LVB
78 * @lock: the lock the LVB is associated with
79 * @lvb: the lock value block
80 *
81 */
82
83static void nolock_unhold_lvb(void *lock, char *lvb)
84{
85 kfree(lvb);
86}
87
88static int nolock_mount(char *table_name, char *host_data,
89 lm_callback_t cb, void *cb_data,
90 unsigned int min_lvb_size, int flags,
91 struct lm_lockstruct *lockstruct,
92 struct kobject *fskobj);
93static void nolock_unmount(void *lockspace);
94
95/* List of registered low-level locking protocols. A file system selects one
96 of them by name at mount time, e.g. lock_nolock, lock_dlm. */
97
98static const struct lm_lockops nolock_ops = {
99 .lm_proto_name = "lock_nolock",
100 .lm_mount = nolock_mount,
101 .lm_unmount = nolock_unmount,
102 .lm_get_lock = nolock_get_lock,
103 .lm_put_lock = nolock_put_lock,
104 .lm_hold_lvb = nolock_hold_lvb,
105 .lm_unhold_lvb = nolock_unhold_lvb,
106};
107
108static struct lmh_wrapper nolock_proto = {
109 .lw_list = LIST_HEAD_INIT(nolock_proto.lw_list),
110 .lw_ops = &nolock_ops,
111};
112
113static LIST_HEAD(lmh_list);
114static DEFINE_MUTEX(lmh_lock);
115
116static int nolock_mount(char *table_name, char *host_data,
117 lm_callback_t cb, void *cb_data,
118 unsigned int min_lvb_size, int flags,
119 struct lm_lockstruct *lockstruct,
120 struct kobject *fskobj)
121{
122 char *c;
123 unsigned int jid;
124 struct nolock_lockspace *nl;
125
126 c = strstr(host_data, "jid=");
127 if (!c)
128 jid = 0;
129 else {
130 c += 4;
131 sscanf(c, "%u", &jid);
132 }
133
134 nl = kzalloc(sizeof(struct nolock_lockspace), GFP_KERNEL);
135 if (!nl)
136 return -ENOMEM;
137
138 nl->nl_lvb_size = min_lvb_size;
139
140 lockstruct->ls_jid = jid;
141 lockstruct->ls_first = 1;
142 lockstruct->ls_lvb_size = min_lvb_size;
143 lockstruct->ls_lockspace = nl;
144 lockstruct->ls_ops = &nolock_ops;
145 lockstruct->ls_flags = LM_LSFLAG_LOCAL;
146
147 return 0;
148}
149
150static void nolock_unmount(void *lockspace)
151{
152 struct nolock_lockspace *nl = lockspace;
153 kfree(nl);
154}
155
156/**
157 * gfs2_register_lockproto - Register a low-level locking protocol
158 * @proto: the protocol definition
159 *
160 * Returns: 0 on success, -EXXX on failure
161 */
162
163int gfs2_register_lockproto(const struct lm_lockops *proto)
164{
165 struct lmh_wrapper *lw;
166
167 mutex_lock(&lmh_lock);
168
169 list_for_each_entry(lw, &lmh_list, lw_list) {
170 if (!strcmp(lw->lw_ops->lm_proto_name, proto->lm_proto_name)) {
171 mutex_unlock(&lmh_lock);
172 printk(KERN_INFO "GFS2: protocol %s already exists\n",
173 proto->lm_proto_name);
174 return -EEXIST;
175 }
176 }
177
178 lw = kzalloc(sizeof(struct lmh_wrapper), GFP_KERNEL);
179 if (!lw) {
180 mutex_unlock(&lmh_lock);
181 return -ENOMEM;
182 }
183
184 lw->lw_ops = proto;
185 list_add(&lw->lw_list, &lmh_list);
186
187 mutex_unlock(&lmh_lock);
188
189 return 0;
190}
191
192/**
193 * gfs2_unregister_lockproto - Unregister a low-level locking protocol
194 * @proto: the protocol definition
195 *
196 */
197
198void gfs2_unregister_lockproto(const struct lm_lockops *proto)
199{
200 struct lmh_wrapper *lw;
201
202 mutex_lock(&lmh_lock);
203
204 list_for_each_entry(lw, &lmh_list, lw_list) {
205 if (!strcmp(lw->lw_ops->lm_proto_name, proto->lm_proto_name)) {
206 list_del(&lw->lw_list);
207 mutex_unlock(&lmh_lock);
208 kfree(lw);
209 return;
210 }
211 }
212
213 mutex_unlock(&lmh_lock);
214
215 printk(KERN_WARNING "GFS2: can't unregister lock protocol %s\n",
216 proto->lm_proto_name);
217}
218
219/**
220 * gfs2_mount_lockproto - Mount a lock protocol
221 * @proto_name - the name of the protocol
222 * @table_name - the name of the lock space
223 * @host_data - data specific to this host
224 * @cb - the callback to the code using the lock module
225 * @sdp - The GFS2 superblock
226 * @min_lvb_size - the mininum LVB size that the caller can deal with
227 * @flags - LM_MFLAG_*
228 * @lockstruct - a structure returned describing the mount
229 *
230 * Returns: 0 on success, -EXXX on failure
231 */
232
233int gfs2_mount_lockproto(char *proto_name, char *table_name, char *host_data,
234 lm_callback_t cb, void *cb_data,
235 unsigned int min_lvb_size, int flags,
236 struct lm_lockstruct *lockstruct,
237 struct kobject *fskobj)
238{
239 struct lmh_wrapper *lw = NULL;
240 int try = 0;
241 int error, found;
242
243
244retry:
245 mutex_lock(&lmh_lock);
246
247 if (list_empty(&nolock_proto.lw_list))
248 list_add(&nolock_proto.lw_list, &lmh_list);
249
250 found = 0;
251 list_for_each_entry(lw, &lmh_list, lw_list) {
252 if (!strcmp(lw->lw_ops->lm_proto_name, proto_name)) {
253 found = 1;
254 break;
255 }
256 }
257
258 if (!found) {
259 if (!try && capable(CAP_SYS_MODULE)) {
260 try = 1;
261 mutex_unlock(&lmh_lock);
262 request_module(proto_name);
263 goto retry;
264 }
265 printk(KERN_INFO "GFS2: can't find protocol %s\n", proto_name);
266 error = -ENOENT;
267 goto out;
268 }
269
270 if (lw->lw_ops->lm_owner &&
271 !try_module_get(lw->lw_ops->lm_owner)) {
272 try = 0;
273 mutex_unlock(&lmh_lock);
274 msleep(1000);
275 goto retry;
276 }
277
278 error = lw->lw_ops->lm_mount(table_name, host_data, cb, cb_data,
279 min_lvb_size, flags, lockstruct, fskobj);
280 if (error)
281 module_put(lw->lw_ops->lm_owner);
282out:
283 mutex_unlock(&lmh_lock);
284 return error;
285}
286
287void gfs2_unmount_lockproto(struct lm_lockstruct *lockstruct)
288{
289 mutex_lock(&lmh_lock);
290 if (lockstruct->ls_ops->lm_unmount)
291 lockstruct->ls_ops->lm_unmount(lockstruct->ls_lockspace);
292 if (lockstruct->ls_ops->lm_owner)
293 module_put(lockstruct->ls_ops->lm_owner);
294 mutex_unlock(&lmh_lock);
295}
296
297/**
298 * gfs2_withdraw_lockproto - abnormally unmount a lock module
299 * @lockstruct: the lockstruct passed into mount
300 *
301 */
302
303void gfs2_withdraw_lockproto(struct lm_lockstruct *lockstruct)
304{
305 mutex_lock(&lmh_lock);
306 lockstruct->ls_ops->lm_withdraw(lockstruct->ls_lockspace);
307 if (lockstruct->ls_ops->lm_owner)
308 module_put(lockstruct->ls_ops->lm_owner);
309 mutex_unlock(&lmh_lock);
310}
311
312EXPORT_SYMBOL_GPL(gfs2_register_lockproto);
313EXPORT_SYMBOL_GPL(gfs2_unregister_lockproto);
314
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-08 17:22:18 -0500