1 /* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * stack_o2cb.c
5 *
6 * Code which interfaces ocfs2 with the o2cb stack.
7 *
8 * Copyright (C) 2007 Oracle. All rights reserved.
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public
12 * License as published by the Free Software Foundation, version 2.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
18 */
19
20 #include <linux/crc32.h>
21 #include <linux/module.h>
22
23 /* Needed for AOP_TRUNCATED_PAGE in mlog_errno() */
24 #include <linux/fs.h>
25
26 #include "cluster/masklog.h"
27 #include "cluster/nodemanager.h"
28 #include "cluster/heartbeat.h"
29
30 #include "stackglue.h"
31
32 struct o2dlm_private {
33 struct dlm_eviction_cb op_eviction_cb;
34 };
35
36 static struct ocfs2_stack_plugin o2cb_stack;
37
38 /* These should be identical */
39 #if (DLM_LOCK_IV != LKM_IVMODE)
40 # error Lock modes do not match
41 #endif
42 #if (DLM_LOCK_NL != LKM_NLMODE)
43 # error Lock modes do not match
44 #endif
45 #if (DLM_LOCK_CR != LKM_CRMODE)
46 # error Lock modes do not match
47 #endif
48 #if (DLM_LOCK_CW != LKM_CWMODE)
49 # error Lock modes do not match
50 #endif
51 #if (DLM_LOCK_PR != LKM_PRMODE)
52 # error Lock modes do not match
53 #endif
54 #if (DLM_LOCK_PW != LKM_PWMODE)
55 # error Lock modes do not match
56 #endif
57 #if (DLM_LOCK_EX != LKM_EXMODE)
58 # error Lock modes do not match
59 #endif
mode_to_o2dlm(int mode)60 static inline int mode_to_o2dlm(int mode)
61 {
62 BUG_ON(mode > LKM_MAXMODE);
63
64 return mode;
65 }
66
67 #define map_flag(_generic, _o2dlm) \
68 if (flags & (_generic)) { \
69 flags &= ~(_generic); \
70 o2dlm_flags |= (_o2dlm); \
71 }
flags_to_o2dlm(u32 flags)72 static int flags_to_o2dlm(u32 flags)
73 {
74 int o2dlm_flags = 0;
75
76 map_flag(DLM_LKF_NOQUEUE, LKM_NOQUEUE);
77 map_flag(DLM_LKF_CANCEL, LKM_CANCEL);
78 map_flag(DLM_LKF_CONVERT, LKM_CONVERT);
79 map_flag(DLM_LKF_VALBLK, LKM_VALBLK);
80 map_flag(DLM_LKF_IVVALBLK, LKM_INVVALBLK);
81 map_flag(DLM_LKF_ORPHAN, LKM_ORPHAN);
82 map_flag(DLM_LKF_FORCEUNLOCK, LKM_FORCE);
83 map_flag(DLM_LKF_TIMEOUT, LKM_TIMEOUT);
84 map_flag(DLM_LKF_LOCAL, LKM_LOCAL);
85
86 /* map_flag() should have cleared every flag passed in */
87 BUG_ON(flags != 0);
88
89 return o2dlm_flags;
90 }
91 #undef map_flag
92
93 /*
94 * Map an o2dlm status to standard errno values.
95 *
96 * o2dlm only uses a handful of these, and returns even fewer to the
97 * caller. Still, we try to assign sane values to each error.
98 *
99 * The following value pairs have special meanings to dlmglue, thus
100 * the right hand side needs to stay unique - never duplicate the
101 * mapping elsewhere in the table!
102 *
103 * DLM_NORMAL: 0
104 * DLM_NOTQUEUED: -EAGAIN
105 * DLM_CANCELGRANT: -EBUSY
106 * DLM_CANCEL: -DLM_ECANCEL
107 */
108 /* Keep in sync with dlmapi.h */
109 static int status_map[] = {
110 [DLM_NORMAL] = 0, /* Success */
111 [DLM_GRANTED] = -EINVAL,
112 [DLM_DENIED] = -EACCES,
113 [DLM_DENIED_NOLOCKS] = -EACCES,
114 [DLM_WORKING] = -EACCES,
115 [DLM_BLOCKED] = -EINVAL,
116 [DLM_BLOCKED_ORPHAN] = -EINVAL,
117 [DLM_DENIED_GRACE_PERIOD] = -EACCES,
118 [DLM_SYSERR] = -ENOMEM, /* It is what it is */
119 [DLM_NOSUPPORT] = -EPROTO,
120 [DLM_CANCELGRANT] = -EBUSY, /* Cancel after grant */
121 [DLM_IVLOCKID] = -EINVAL,
122 [DLM_SYNC] = -EINVAL,
123 [DLM_BADTYPE] = -EINVAL,
124 [DLM_BADRESOURCE] = -EINVAL,
125 [DLM_MAXHANDLES] = -ENOMEM,
126 [DLM_NOCLINFO] = -EINVAL,
127 [DLM_NOLOCKMGR] = -EINVAL,
128 [DLM_NOPURGED] = -EINVAL,
129 [DLM_BADARGS] = -EINVAL,
130 [DLM_VOID] = -EINVAL,
131 [DLM_NOTQUEUED] = -EAGAIN, /* Trylock failed */
132 [DLM_IVBUFLEN] = -EINVAL,
133 [DLM_CVTUNGRANT] = -EPERM,
134 [DLM_BADPARAM] = -EINVAL,
135 [DLM_VALNOTVALID] = -EINVAL,
136 [DLM_REJECTED] = -EPERM,
137 [DLM_ABORT] = -EINVAL,
138 [DLM_CANCEL] = -DLM_ECANCEL, /* Successful cancel */
139 [DLM_IVRESHANDLE] = -EINVAL,
140 [DLM_DEADLOCK] = -EDEADLK,
141 [DLM_DENIED_NOASTS] = -EINVAL,
142 [DLM_FORWARD] = -EINVAL,
143 [DLM_TIMEOUT] = -ETIMEDOUT,
144 [DLM_IVGROUPID] = -EINVAL,
145 [DLM_VERS_CONFLICT] = -EOPNOTSUPP,
146 [DLM_BAD_DEVICE_PATH] = -ENOENT,
147 [DLM_NO_DEVICE_PERMISSION] = -EPERM,
148 [DLM_NO_CONTROL_DEVICE] = -ENOENT,
149 [DLM_RECOVERING] = -ENOTCONN,
150 [DLM_MIGRATING] = -ERESTART,
151 [DLM_MAXSTATS] = -EINVAL,
152 };
153
dlm_status_to_errno(enum dlm_status status)154 static int dlm_status_to_errno(enum dlm_status status)
155 {
156 BUG_ON(status > (sizeof(status_map) / sizeof(status_map[0])));
157
158 return status_map[status];
159 }
160
o2dlm_lock_ast_wrapper(void * astarg)161 static void o2dlm_lock_ast_wrapper(void *astarg)
162 {
163 BUG_ON(o2cb_stack.sp_proto == NULL);
164
165 o2cb_stack.sp_proto->lp_lock_ast(astarg);
166 }
167
o2dlm_blocking_ast_wrapper(void * astarg,int level)168 static void o2dlm_blocking_ast_wrapper(void *astarg, int level)
169 {
170 BUG_ON(o2cb_stack.sp_proto == NULL);
171
172 o2cb_stack.sp_proto->lp_blocking_ast(astarg, level);
173 }
174
o2dlm_unlock_ast_wrapper(void * astarg,enum dlm_status status)175 static void o2dlm_unlock_ast_wrapper(void *astarg, enum dlm_status status)
176 {
177 int error = dlm_status_to_errno(status);
178
179 BUG_ON(o2cb_stack.sp_proto == NULL);
180
181 /*
182 * In o2dlm, you can get both the lock_ast() for the lock being
183 * granted and the unlock_ast() for the CANCEL failing. A
184 * successful cancel sends DLM_NORMAL here. If the
185 * lock grant happened before the cancel arrived, you get
186 * DLM_CANCELGRANT.
187 *
188 * There's no need for the double-ast. If we see DLM_CANCELGRANT,
189 * we just ignore it. We expect the lock_ast() to handle the
190 * granted lock.
191 */
192 if (status == DLM_CANCELGRANT)
193 return;
194
195 o2cb_stack.sp_proto->lp_unlock_ast(astarg, error);
196 }
197
o2cb_dlm_lock(struct ocfs2_cluster_connection * conn,int mode,union ocfs2_dlm_lksb * lksb,u32 flags,void * name,unsigned int namelen,void * astarg)198 static int o2cb_dlm_lock(struct ocfs2_cluster_connection *conn,
199 int mode,
200 union ocfs2_dlm_lksb *lksb,
201 u32 flags,
202 void *name,
203 unsigned int namelen,
204 void *astarg)
205 {
206 enum dlm_status status;
207 int o2dlm_mode = mode_to_o2dlm(mode);
208 int o2dlm_flags = flags_to_o2dlm(flags);
209 int ret;
210
211 status = dlmlock(conn->cc_lockspace, o2dlm_mode, &lksb->lksb_o2dlm,
212 o2dlm_flags, name, namelen,
213 o2dlm_lock_ast_wrapper, astarg,
214 o2dlm_blocking_ast_wrapper);
215 ret = dlm_status_to_errno(status);
216 return ret;
217 }
218
o2cb_dlm_unlock(struct ocfs2_cluster_connection * conn,union ocfs2_dlm_lksb * lksb,u32 flags,void * astarg)219 static int o2cb_dlm_unlock(struct ocfs2_cluster_connection *conn,
220 union ocfs2_dlm_lksb *lksb,
221 u32 flags,
222 void *astarg)
223 {
224 enum dlm_status status;
225 int o2dlm_flags = flags_to_o2dlm(flags);
226 int ret;
227
228 status = dlmunlock(conn->cc_lockspace, &lksb->lksb_o2dlm,
229 o2dlm_flags, o2dlm_unlock_ast_wrapper, astarg);
230 ret = dlm_status_to_errno(status);
231 return ret;
232 }
233
o2cb_dlm_lock_status(union ocfs2_dlm_lksb * lksb)234 static int o2cb_dlm_lock_status(union ocfs2_dlm_lksb *lksb)
235 {
236 return dlm_status_to_errno(lksb->lksb_o2dlm.status);
237 }
238
o2cb_dlm_lvb(union ocfs2_dlm_lksb * lksb)239 static void *o2cb_dlm_lvb(union ocfs2_dlm_lksb *lksb)
240 {
241 return (void *)(lksb->lksb_o2dlm.lvb);
242 }
243
o2cb_dump_lksb(union ocfs2_dlm_lksb * lksb)244 static void o2cb_dump_lksb(union ocfs2_dlm_lksb *lksb)
245 {
246 dlm_print_one_lock(lksb->lksb_o2dlm.lockid);
247 }
248
249 /*
250 * Called from the dlm when it's about to evict a node. This is how the
251 * classic stack signals node death.
252 */
o2dlm_eviction_cb(int node_num,void * data)253 static void o2dlm_eviction_cb(int node_num, void *data)
254 {
255 struct ocfs2_cluster_connection *conn = data;
256
257 mlog(ML_NOTICE, "o2dlm has evicted node %d from group %.*s\n",
258 node_num, conn->cc_namelen, conn->cc_name);
259
260 conn->cc_recovery_handler(node_num, conn->cc_recovery_data);
261 }
262
o2cb_cluster_connect(struct ocfs2_cluster_connection * conn)263 static int o2cb_cluster_connect(struct ocfs2_cluster_connection *conn)
264 {
265 int rc = 0;
266 u32 dlm_key;
267 struct dlm_ctxt *dlm;
268 struct o2dlm_private *priv;
269 struct dlm_protocol_version dlm_version;
270
271 BUG_ON(conn == NULL);
272 BUG_ON(o2cb_stack.sp_proto == NULL);
273
274 /* for now we only have one cluster/node, make sure we see it
275 * in the heartbeat universe */
276 if (!o2hb_check_local_node_heartbeating()) {
277 rc = -EINVAL;
278 goto out;
279 }
280
281 priv = kzalloc(sizeof(struct o2dlm_private), GFP_KERNEL);
282 if (!priv) {
283 rc = -ENOMEM;
284 goto out_free;
285 }
286
287 /* This just fills the structure in. It is safe to pass conn. */
288 dlm_setup_eviction_cb(&priv->op_eviction_cb, o2dlm_eviction_cb,
289 conn);
290
291 conn->cc_private = priv;
292
293 /* used by the dlm code to make message headers unique, each
294 * node in this domain must agree on this. */
295 dlm_key = crc32_le(0, conn->cc_name, conn->cc_namelen);
296 dlm_version.pv_major = conn->cc_version.pv_major;
297 dlm_version.pv_minor = conn->cc_version.pv_minor;
298
299 dlm = dlm_register_domain(conn->cc_name, dlm_key, &dlm_version);
300 if (IS_ERR(dlm)) {
301 rc = PTR_ERR(dlm);
302 mlog_errno(rc);
303 goto out_free;
304 }
305
306 conn->cc_version.pv_major = dlm_version.pv_major;
307 conn->cc_version.pv_minor = dlm_version.pv_minor;
308 conn->cc_lockspace = dlm;
309
310 dlm_register_eviction_cb(dlm, &priv->op_eviction_cb);
311
312 out_free:
313 if (rc && conn->cc_private)
314 kfree(conn->cc_private);
315
316 out:
317 return rc;
318 }
319
o2cb_cluster_disconnect(struct ocfs2_cluster_connection * conn)320 static int o2cb_cluster_disconnect(struct ocfs2_cluster_connection *conn)
321 {
322 struct dlm_ctxt *dlm = conn->cc_lockspace;
323 struct o2dlm_private *priv = conn->cc_private;
324
325 dlm_unregister_eviction_cb(&priv->op_eviction_cb);
326 conn->cc_private = NULL;
327 kfree(priv);
328
329 dlm_unregister_domain(dlm);
330 conn->cc_lockspace = NULL;
331
332 return 0;
333 }
334
o2cb_cluster_this_node(unsigned int * node)335 static int o2cb_cluster_this_node(unsigned int *node)
336 {
337 int node_num;
338
339 node_num = o2nm_this_node();
340 if (node_num == O2NM_INVALID_NODE_NUM)
341 return -ENOENT;
342
343 if (node_num >= O2NM_MAX_NODES)
344 return -EOVERFLOW;
345
346 *node = node_num;
347 return 0;
348 }
349
350 static struct ocfs2_stack_operations o2cb_stack_ops = {
351 .connect = o2cb_cluster_connect,
352 .disconnect = o2cb_cluster_disconnect,
353 .this_node = o2cb_cluster_this_node,
354 .dlm_lock = o2cb_dlm_lock,
355 .dlm_unlock = o2cb_dlm_unlock,
356 .lock_status = o2cb_dlm_lock_status,
357 .lock_lvb = o2cb_dlm_lvb,
358 .dump_lksb = o2cb_dump_lksb,
359 };
360
361 static struct ocfs2_stack_plugin o2cb_stack = {
362 .sp_name = "o2cb",
363 .sp_ops = &o2cb_stack_ops,
364 .sp_owner = THIS_MODULE,
365 };
366
o2cb_stack_init(void)367 static int __init o2cb_stack_init(void)
368 {
369 return ocfs2_stack_glue_register(&o2cb_stack);
370 }
371
o2cb_stack_exit(void)372 static void __exit o2cb_stack_exit(void)
373 {
374 ocfs2_stack_glue_unregister(&o2cb_stack);
375 }
376
377 MODULE_AUTHOR("Oracle");
378 MODULE_DESCRIPTION("ocfs2 driver for the classic o2cb stack");
379 MODULE_LICENSE("GPL");
380 module_init(o2cb_stack_init);
381 module_exit(o2cb_stack_exit);
382