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/kernel.h>
21 #include <linux/crc32.h>
22 #include <linux/slab.h>
23 #include <linux/module.h>
24
25 /* Needed for AOP_TRUNCATED_PAGE in mlog_errno() */
26 #include <linux/fs.h>
27
28 #include "cluster/masklog.h"
29 #include "cluster/nodemanager.h"
30 #include "cluster/heartbeat.h"
31 #include "cluster/tcp.h"
32
33 #include "stackglue.h"
34
35 struct o2dlm_private {
36 struct dlm_eviction_cb op_eviction_cb;
37 };
38
39 static struct ocfs2_stack_plugin o2cb_stack;
40
41 /* These should be identical */
42 #if (DLM_LOCK_IV != LKM_IVMODE)
43 # error Lock modes do not match
44 #endif
45 #if (DLM_LOCK_NL != LKM_NLMODE)
46 # error Lock modes do not match
47 #endif
48 #if (DLM_LOCK_CR != LKM_CRMODE)
49 # error Lock modes do not match
50 #endif
51 #if (DLM_LOCK_CW != LKM_CWMODE)
52 # error Lock modes do not match
53 #endif
54 #if (DLM_LOCK_PR != LKM_PRMODE)
55 # error Lock modes do not match
56 #endif
57 #if (DLM_LOCK_PW != LKM_PWMODE)
58 # error Lock modes do not match
59 #endif
60 #if (DLM_LOCK_EX != LKM_EXMODE)
61 # error Lock modes do not match
62 #endif
mode_to_o2dlm(int mode)63 static inline int mode_to_o2dlm(int mode)
64 {
65 BUG_ON(mode > LKM_MAXMODE);
66
67 return mode;
68 }
69
70 #define map_flag(_generic, _o2dlm) \
71 if (flags & (_generic)) { \
72 flags &= ~(_generic); \
73 o2dlm_flags |= (_o2dlm); \
74 }
flags_to_o2dlm(u32 flags)75 static int flags_to_o2dlm(u32 flags)
76 {
77 int o2dlm_flags = 0;
78
79 map_flag(DLM_LKF_NOQUEUE, LKM_NOQUEUE);
80 map_flag(DLM_LKF_CANCEL, LKM_CANCEL);
81 map_flag(DLM_LKF_CONVERT, LKM_CONVERT);
82 map_flag(DLM_LKF_VALBLK, LKM_VALBLK);
83 map_flag(DLM_LKF_IVVALBLK, LKM_INVVALBLK);
84 map_flag(DLM_LKF_ORPHAN, LKM_ORPHAN);
85 map_flag(DLM_LKF_FORCEUNLOCK, LKM_FORCE);
86 map_flag(DLM_LKF_TIMEOUT, LKM_TIMEOUT);
87 map_flag(DLM_LKF_LOCAL, LKM_LOCAL);
88
89 /* map_flag() should have cleared every flag passed in */
90 BUG_ON(flags != 0);
91
92 return o2dlm_flags;
93 }
94 #undef map_flag
95
96 /*
97 * Map an o2dlm status to standard errno values.
98 *
99 * o2dlm only uses a handful of these, and returns even fewer to the
100 * caller. Still, we try to assign sane values to each error.
101 *
102 * The following value pairs have special meanings to dlmglue, thus
103 * the right hand side needs to stay unique - never duplicate the
104 * mapping elsewhere in the table!
105 *
106 * DLM_NORMAL: 0
107 * DLM_NOTQUEUED: -EAGAIN
108 * DLM_CANCELGRANT: -EBUSY
109 * DLM_CANCEL: -DLM_ECANCEL
110 */
111 /* Keep in sync with dlmapi.h */
112 static int status_map[] = {
113 [DLM_NORMAL] = 0, /* Success */
114 [DLM_GRANTED] = -EINVAL,
115 [DLM_DENIED] = -EACCES,
116 [DLM_DENIED_NOLOCKS] = -EACCES,
117 [DLM_WORKING] = -EACCES,
118 [DLM_BLOCKED] = -EINVAL,
119 [DLM_BLOCKED_ORPHAN] = -EINVAL,
120 [DLM_DENIED_GRACE_PERIOD] = -EACCES,
121 [DLM_SYSERR] = -ENOMEM, /* It is what it is */
122 [DLM_NOSUPPORT] = -EPROTO,
123 [DLM_CANCELGRANT] = -EBUSY, /* Cancel after grant */
124 [DLM_IVLOCKID] = -EINVAL,
125 [DLM_SYNC] = -EINVAL,
126 [DLM_BADTYPE] = -EINVAL,
127 [DLM_BADRESOURCE] = -EINVAL,
128 [DLM_MAXHANDLES] = -ENOMEM,
129 [DLM_NOCLINFO] = -EINVAL,
130 [DLM_NOLOCKMGR] = -EINVAL,
131 [DLM_NOPURGED] = -EINVAL,
132 [DLM_BADARGS] = -EINVAL,
133 [DLM_VOID] = -EINVAL,
134 [DLM_NOTQUEUED] = -EAGAIN, /* Trylock failed */
135 [DLM_IVBUFLEN] = -EINVAL,
136 [DLM_CVTUNGRANT] = -EPERM,
137 [DLM_BADPARAM] = -EINVAL,
138 [DLM_VALNOTVALID] = -EINVAL,
139 [DLM_REJECTED] = -EPERM,
140 [DLM_ABORT] = -EINVAL,
141 [DLM_CANCEL] = -DLM_ECANCEL, /* Successful cancel */
142 [DLM_IVRESHANDLE] = -EINVAL,
143 [DLM_DEADLOCK] = -EDEADLK,
144 [DLM_DENIED_NOASTS] = -EINVAL,
145 [DLM_FORWARD] = -EINVAL,
146 [DLM_TIMEOUT] = -ETIMEDOUT,
147 [DLM_IVGROUPID] = -EINVAL,
148 [DLM_VERS_CONFLICT] = -EOPNOTSUPP,
149 [DLM_BAD_DEVICE_PATH] = -ENOENT,
150 [DLM_NO_DEVICE_PERMISSION] = -EPERM,
151 [DLM_NO_CONTROL_DEVICE] = -ENOENT,
152 [DLM_RECOVERING] = -ENOTCONN,
153 [DLM_MIGRATING] = -ERESTART,
154 [DLM_MAXSTATS] = -EINVAL,
155 };
156
dlm_status_to_errno(enum dlm_status status)157 static int dlm_status_to_errno(enum dlm_status status)
158 {
159 BUG_ON(status < 0 || status >= ARRAY_SIZE(status_map));
160
161 return status_map[status];
162 }
163
o2dlm_lock_ast_wrapper(void * astarg)164 static void o2dlm_lock_ast_wrapper(void *astarg)
165 {
166 struct ocfs2_dlm_lksb *lksb = astarg;
167
168 lksb->lksb_conn->cc_proto->lp_lock_ast(lksb);
169 }
170
o2dlm_blocking_ast_wrapper(void * astarg,int level)171 static void o2dlm_blocking_ast_wrapper(void *astarg, int level)
172 {
173 struct ocfs2_dlm_lksb *lksb = astarg;
174
175 lksb->lksb_conn->cc_proto->lp_blocking_ast(lksb, level);
176 }
177
o2dlm_unlock_ast_wrapper(void * astarg,enum dlm_status status)178 static void o2dlm_unlock_ast_wrapper(void *astarg, enum dlm_status status)
179 {
180 struct ocfs2_dlm_lksb *lksb = astarg;
181 int error = dlm_status_to_errno(status);
182
183 /*
184 * In o2dlm, you can get both the lock_ast() for the lock being
185 * granted and the unlock_ast() for the CANCEL failing. A
186 * successful cancel sends DLM_NORMAL here. If the
187 * lock grant happened before the cancel arrived, you get
188 * DLM_CANCELGRANT.
189 *
190 * There's no need for the double-ast. If we see DLM_CANCELGRANT,
191 * we just ignore it. We expect the lock_ast() to handle the
192 * granted lock.
193 */
194 if (status == DLM_CANCELGRANT)
195 return;
196
197 lksb->lksb_conn->cc_proto->lp_unlock_ast(lksb, error);
198 }
199
o2cb_dlm_lock(struct ocfs2_cluster_connection * conn,int mode,struct ocfs2_dlm_lksb * lksb,u32 flags,void * name,unsigned int namelen)200 static int o2cb_dlm_lock(struct ocfs2_cluster_connection *conn,
201 int mode,
202 struct ocfs2_dlm_lksb *lksb,
203 u32 flags,
204 void *name,
205 unsigned int namelen)
206 {
207 enum dlm_status status;
208 int o2dlm_mode = mode_to_o2dlm(mode);
209 int o2dlm_flags = flags_to_o2dlm(flags);
210 int ret;
211
212 status = dlmlock(conn->cc_lockspace, o2dlm_mode, &lksb->lksb_o2dlm,
213 o2dlm_flags, name, namelen,
214 o2dlm_lock_ast_wrapper, lksb,
215 o2dlm_blocking_ast_wrapper);
216 ret = dlm_status_to_errno(status);
217 return ret;
218 }
219
o2cb_dlm_unlock(struct ocfs2_cluster_connection * conn,struct ocfs2_dlm_lksb * lksb,u32 flags)220 static int o2cb_dlm_unlock(struct ocfs2_cluster_connection *conn,
221 struct ocfs2_dlm_lksb *lksb,
222 u32 flags)
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, lksb);
230 ret = dlm_status_to_errno(status);
231 return ret;
232 }
233
o2cb_dlm_lock_status(struct ocfs2_dlm_lksb * lksb)234 static int o2cb_dlm_lock_status(struct ocfs2_dlm_lksb *lksb)
235 {
236 return dlm_status_to_errno(lksb->lksb_o2dlm.status);
237 }
238
239 /*
240 * o2dlm aways has a "valid" LVB. If the dlm loses track of the LVB
241 * contents, it will zero out the LVB. Thus the caller can always trust
242 * the contents.
243 */
o2cb_dlm_lvb_valid(struct ocfs2_dlm_lksb * lksb)244 static int o2cb_dlm_lvb_valid(struct ocfs2_dlm_lksb *lksb)
245 {
246 return 1;
247 }
248
o2cb_dlm_lvb(struct ocfs2_dlm_lksb * lksb)249 static void *o2cb_dlm_lvb(struct ocfs2_dlm_lksb *lksb)
250 {
251 return (void *)(lksb->lksb_o2dlm.lvb);
252 }
253
o2cb_dump_lksb(struct ocfs2_dlm_lksb * lksb)254 static void o2cb_dump_lksb(struct ocfs2_dlm_lksb *lksb)
255 {
256 dlm_print_one_lock(lksb->lksb_o2dlm.lockid);
257 }
258
259 /*
260 * Check if this node is heartbeating and is connected to all other
261 * heartbeating nodes.
262 */
o2cb_cluster_check(void)263 static int o2cb_cluster_check(void)
264 {
265 u8 node_num;
266 int i;
267 unsigned long hbmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
268 unsigned long netmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
269
270 node_num = o2nm_this_node();
271 if (node_num == O2NM_MAX_NODES) {
272 printk(KERN_ERR "o2cb: This node has not been configured.\n");
273 return -EINVAL;
274 }
275
276 /*
277 * o2dlm expects o2net sockets to be created. If not, then
278 * dlm_join_domain() fails with a stack of errors which are both cryptic
279 * and incomplete. The idea here is to detect upfront whether we have
280 * managed to connect to all nodes or not. If not, then list the nodes
281 * to allow the user to check the configuration (incorrect IP, firewall,
282 * etc.) Yes, this is racy. But its not the end of the world.
283 */
284 #define O2CB_MAP_STABILIZE_COUNT 60
285 for (i = 0; i < O2CB_MAP_STABILIZE_COUNT; ++i) {
286 o2hb_fill_node_map(hbmap, sizeof(hbmap));
287 if (!test_bit(node_num, hbmap)) {
288 printk(KERN_ERR "o2cb: %s heartbeat has not been "
289 "started.\n", (o2hb_global_heartbeat_active() ?
290 "Global" : "Local"));
291 return -EINVAL;
292 }
293 o2net_fill_node_map(netmap, sizeof(netmap));
294 /* Force set the current node to allow easy compare */
295 set_bit(node_num, netmap);
296 if (!memcmp(hbmap, netmap, sizeof(hbmap)))
297 return 0;
298 if (i < O2CB_MAP_STABILIZE_COUNT)
299 msleep(1000);
300 }
301
302 printk(KERN_ERR "o2cb: This node could not connect to nodes:");
303 i = -1;
304 while ((i = find_next_bit(hbmap, O2NM_MAX_NODES,
305 i + 1)) < O2NM_MAX_NODES) {
306 if (!test_bit(i, netmap))
307 printk(" %u", i);
308 }
309 printk(".\n");
310
311 return -ENOTCONN;
312 }
313
314 /*
315 * Called from the dlm when it's about to evict a node. This is how the
316 * classic stack signals node death.
317 */
o2dlm_eviction_cb(int node_num,void * data)318 static void o2dlm_eviction_cb(int node_num, void *data)
319 {
320 struct ocfs2_cluster_connection *conn = data;
321
322 printk(KERN_NOTICE "o2cb: o2dlm has evicted node %d from domain %.*s\n",
323 node_num, conn->cc_namelen, conn->cc_name);
324
325 conn->cc_recovery_handler(node_num, conn->cc_recovery_data);
326 }
327
o2cb_cluster_connect(struct ocfs2_cluster_connection * conn)328 static int o2cb_cluster_connect(struct ocfs2_cluster_connection *conn)
329 {
330 int rc = 0;
331 u32 dlm_key;
332 struct dlm_ctxt *dlm;
333 struct o2dlm_private *priv;
334 struct dlm_protocol_version fs_version;
335
336 BUG_ON(conn == NULL);
337 BUG_ON(conn->cc_proto == NULL);
338
339 /* Ensure cluster stack is up and all nodes are connected */
340 rc = o2cb_cluster_check();
341 if (rc) {
342 printk(KERN_ERR "o2cb: Cluster check failed. Fix errors "
343 "before retrying.\n");
344 goto out;
345 }
346
347 priv = kzalloc(sizeof(struct o2dlm_private), GFP_KERNEL);
348 if (!priv) {
349 rc = -ENOMEM;
350 goto out_free;
351 }
352
353 /* This just fills the structure in. It is safe to pass conn. */
354 dlm_setup_eviction_cb(&priv->op_eviction_cb, o2dlm_eviction_cb,
355 conn);
356
357 conn->cc_private = priv;
358
359 /* used by the dlm code to make message headers unique, each
360 * node in this domain must agree on this. */
361 dlm_key = crc32_le(0, conn->cc_name, conn->cc_namelen);
362 fs_version.pv_major = conn->cc_version.pv_major;
363 fs_version.pv_minor = conn->cc_version.pv_minor;
364
365 dlm = dlm_register_domain(conn->cc_name, dlm_key, &fs_version);
366 if (IS_ERR(dlm)) {
367 rc = PTR_ERR(dlm);
368 mlog_errno(rc);
369 goto out_free;
370 }
371
372 conn->cc_version.pv_major = fs_version.pv_major;
373 conn->cc_version.pv_minor = fs_version.pv_minor;
374 conn->cc_lockspace = dlm;
375
376 dlm_register_eviction_cb(dlm, &priv->op_eviction_cb);
377
378 out_free:
379 if (rc && conn->cc_private)
380 kfree(conn->cc_private);
381
382 out:
383 return rc;
384 }
385
o2cb_cluster_disconnect(struct ocfs2_cluster_connection * conn)386 static int o2cb_cluster_disconnect(struct ocfs2_cluster_connection *conn)
387 {
388 struct dlm_ctxt *dlm = conn->cc_lockspace;
389 struct o2dlm_private *priv = conn->cc_private;
390
391 dlm_unregister_eviction_cb(&priv->op_eviction_cb);
392 conn->cc_private = NULL;
393 kfree(priv);
394
395 dlm_unregister_domain(dlm);
396 conn->cc_lockspace = NULL;
397
398 return 0;
399 }
400
o2cb_cluster_this_node(unsigned int * node)401 static int o2cb_cluster_this_node(unsigned int *node)
402 {
403 int node_num;
404
405 node_num = o2nm_this_node();
406 if (node_num == O2NM_INVALID_NODE_NUM)
407 return -ENOENT;
408
409 if (node_num >= O2NM_MAX_NODES)
410 return -EOVERFLOW;
411
412 *node = node_num;
413 return 0;
414 }
415
416 static struct ocfs2_stack_operations o2cb_stack_ops = {
417 .connect = o2cb_cluster_connect,
418 .disconnect = o2cb_cluster_disconnect,
419 .this_node = o2cb_cluster_this_node,
420 .dlm_lock = o2cb_dlm_lock,
421 .dlm_unlock = o2cb_dlm_unlock,
422 .lock_status = o2cb_dlm_lock_status,
423 .lvb_valid = o2cb_dlm_lvb_valid,
424 .lock_lvb = o2cb_dlm_lvb,
425 .dump_lksb = o2cb_dump_lksb,
426 };
427
428 static struct ocfs2_stack_plugin o2cb_stack = {
429 .sp_name = "o2cb",
430 .sp_ops = &o2cb_stack_ops,
431 .sp_owner = THIS_MODULE,
432 };
433
o2cb_stack_init(void)434 static int __init o2cb_stack_init(void)
435 {
436 return ocfs2_stack_glue_register(&o2cb_stack);
437 }
438
o2cb_stack_exit(void)439 static void __exit o2cb_stack_exit(void)
440 {
441 ocfs2_stack_glue_unregister(&o2cb_stack);
442 }
443
444 MODULE_AUTHOR("Oracle");
445 MODULE_DESCRIPTION("ocfs2 driver for the classic o2cb stack");
446 MODULE_LICENSE("GPL");
447 module_init(o2cb_stack_init);
448 module_exit(o2cb_stack_exit);
449