xref: /openbmc/linux/fs/ocfs2/stack_o2cb.c (revision d9fd5a71)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* -*- mode: c; c-basic-offset: 8; -*-
3  * vim: noexpandtab sw=8 ts=8 sts=0:
4  *
5  * stack_o2cb.c
6  *
7  * Code which interfaces ocfs2 with the o2cb stack.
8  *
9  * Copyright (C) 2007 Oracle.  All rights reserved.
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/crc32.h>
14 #include <linux/slab.h>
15 #include <linux/module.h>
16 
17 /* Needed for AOP_TRUNCATED_PAGE in mlog_errno() */
18 #include <linux/fs.h>
19 
20 #include "cluster/masklog.h"
21 #include "cluster/nodemanager.h"
22 #include "cluster/heartbeat.h"
23 #include "cluster/tcp.h"
24 
25 #include "stackglue.h"
26 
27 struct o2dlm_private {
28 	struct dlm_eviction_cb op_eviction_cb;
29 };
30 
31 static struct ocfs2_stack_plugin o2cb_stack;
32 
33 /* These should be identical */
34 #if (DLM_LOCK_IV != LKM_IVMODE)
35 # error Lock modes do not match
36 #endif
37 #if (DLM_LOCK_NL != LKM_NLMODE)
38 # error Lock modes do not match
39 #endif
40 #if (DLM_LOCK_CR != LKM_CRMODE)
41 # error Lock modes do not match
42 #endif
43 #if (DLM_LOCK_CW != LKM_CWMODE)
44 # error Lock modes do not match
45 #endif
46 #if (DLM_LOCK_PR != LKM_PRMODE)
47 # error Lock modes do not match
48 #endif
49 #if (DLM_LOCK_PW != LKM_PWMODE)
50 # error Lock modes do not match
51 #endif
52 #if (DLM_LOCK_EX != LKM_EXMODE)
53 # error Lock modes do not match
54 #endif
55 static inline int mode_to_o2dlm(int mode)
56 {
57 	BUG_ON(mode > LKM_MAXMODE);
58 
59 	return mode;
60 }
61 
62 #define map_flag(_generic, _o2dlm)		\
63 	if (flags & (_generic)) {		\
64 		flags &= ~(_generic);		\
65 		o2dlm_flags |= (_o2dlm);	\
66 	}
67 static int flags_to_o2dlm(u32 flags)
68 {
69 	int o2dlm_flags = 0;
70 
71 	map_flag(DLM_LKF_NOQUEUE, LKM_NOQUEUE);
72 	map_flag(DLM_LKF_CANCEL, LKM_CANCEL);
73 	map_flag(DLM_LKF_CONVERT, LKM_CONVERT);
74 	map_flag(DLM_LKF_VALBLK, LKM_VALBLK);
75 	map_flag(DLM_LKF_IVVALBLK, LKM_INVVALBLK);
76 	map_flag(DLM_LKF_ORPHAN, LKM_ORPHAN);
77 	map_flag(DLM_LKF_FORCEUNLOCK, LKM_FORCE);
78 	map_flag(DLM_LKF_TIMEOUT, LKM_TIMEOUT);
79 	map_flag(DLM_LKF_LOCAL, LKM_LOCAL);
80 
81 	/* map_flag() should have cleared every flag passed in */
82 	BUG_ON(flags != 0);
83 
84 	return o2dlm_flags;
85 }
86 #undef map_flag
87 
88 /*
89  * Map an o2dlm status to standard errno values.
90  *
91  * o2dlm only uses a handful of these, and returns even fewer to the
92  * caller. Still, we try to assign sane values to each error.
93  *
94  * The following value pairs have special meanings to dlmglue, thus
95  * the right hand side needs to stay unique - never duplicate the
96  * mapping elsewhere in the table!
97  *
98  * DLM_NORMAL:		0
99  * DLM_NOTQUEUED:	-EAGAIN
100  * DLM_CANCELGRANT:	-EBUSY
101  * DLM_CANCEL:		-DLM_ECANCEL
102  */
103 /* Keep in sync with dlmapi.h */
104 static int status_map[] = {
105 	[DLM_NORMAL]			= 0,		/* Success */
106 	[DLM_GRANTED]			= -EINVAL,
107 	[DLM_DENIED]			= -EACCES,
108 	[DLM_DENIED_NOLOCKS]		= -EACCES,
109 	[DLM_WORKING]			= -EACCES,
110 	[DLM_BLOCKED]			= -EINVAL,
111 	[DLM_BLOCKED_ORPHAN]		= -EINVAL,
112 	[DLM_DENIED_GRACE_PERIOD]	= -EACCES,
113 	[DLM_SYSERR]			= -ENOMEM,	/* It is what it is */
114 	[DLM_NOSUPPORT]			= -EPROTO,
115 	[DLM_CANCELGRANT]		= -EBUSY,	/* Cancel after grant */
116 	[DLM_IVLOCKID]			= -EINVAL,
117 	[DLM_SYNC]			= -EINVAL,
118 	[DLM_BADTYPE]			= -EINVAL,
119 	[DLM_BADRESOURCE]		= -EINVAL,
120 	[DLM_MAXHANDLES]		= -ENOMEM,
121 	[DLM_NOCLINFO]			= -EINVAL,
122 	[DLM_NOLOCKMGR]			= -EINVAL,
123 	[DLM_NOPURGED]			= -EINVAL,
124 	[DLM_BADARGS]			= -EINVAL,
125 	[DLM_VOID]			= -EINVAL,
126 	[DLM_NOTQUEUED]			= -EAGAIN,	/* Trylock failed */
127 	[DLM_IVBUFLEN]			= -EINVAL,
128 	[DLM_CVTUNGRANT]		= -EPERM,
129 	[DLM_BADPARAM]			= -EINVAL,
130 	[DLM_VALNOTVALID]		= -EINVAL,
131 	[DLM_REJECTED]			= -EPERM,
132 	[DLM_ABORT]			= -EINVAL,
133 	[DLM_CANCEL]			= -DLM_ECANCEL,	/* Successful cancel */
134 	[DLM_IVRESHANDLE]		= -EINVAL,
135 	[DLM_DEADLOCK]			= -EDEADLK,
136 	[DLM_DENIED_NOASTS]		= -EINVAL,
137 	[DLM_FORWARD]			= -EINVAL,
138 	[DLM_TIMEOUT]			= -ETIMEDOUT,
139 	[DLM_IVGROUPID]			= -EINVAL,
140 	[DLM_VERS_CONFLICT]		= -EOPNOTSUPP,
141 	[DLM_BAD_DEVICE_PATH]		= -ENOENT,
142 	[DLM_NO_DEVICE_PERMISSION]	= -EPERM,
143 	[DLM_NO_CONTROL_DEVICE]		= -ENOENT,
144 	[DLM_RECOVERING]		= -ENOTCONN,
145 	[DLM_MIGRATING]			= -ERESTART,
146 	[DLM_MAXSTATS]			= -EINVAL,
147 };
148 
149 static int dlm_status_to_errno(enum dlm_status status)
150 {
151 	BUG_ON(status < 0 || status >= ARRAY_SIZE(status_map));
152 
153 	return status_map[status];
154 }
155 
156 static void o2dlm_lock_ast_wrapper(void *astarg)
157 {
158 	struct ocfs2_dlm_lksb *lksb = astarg;
159 
160 	lksb->lksb_conn->cc_proto->lp_lock_ast(lksb);
161 }
162 
163 static void o2dlm_blocking_ast_wrapper(void *astarg, int level)
164 {
165 	struct ocfs2_dlm_lksb *lksb = astarg;
166 
167 	lksb->lksb_conn->cc_proto->lp_blocking_ast(lksb, level);
168 }
169 
170 static void o2dlm_unlock_ast_wrapper(void *astarg, enum dlm_status status)
171 {
172 	struct ocfs2_dlm_lksb *lksb = astarg;
173 	int error = dlm_status_to_errno(status);
174 
175 	/*
176 	 * In o2dlm, you can get both the lock_ast() for the lock being
177 	 * granted and the unlock_ast() for the CANCEL failing.  A
178 	 * successful cancel sends DLM_NORMAL here.  If the
179 	 * lock grant happened before the cancel arrived, you get
180 	 * DLM_CANCELGRANT.
181 	 *
182 	 * There's no need for the double-ast.  If we see DLM_CANCELGRANT,
183 	 * we just ignore it.  We expect the lock_ast() to handle the
184 	 * granted lock.
185 	 */
186 	if (status == DLM_CANCELGRANT)
187 		return;
188 
189 	lksb->lksb_conn->cc_proto->lp_unlock_ast(lksb, error);
190 }
191 
192 static int o2cb_dlm_lock(struct ocfs2_cluster_connection *conn,
193 			 int mode,
194 			 struct ocfs2_dlm_lksb *lksb,
195 			 u32 flags,
196 			 void *name,
197 			 unsigned int namelen)
198 {
199 	enum dlm_status status;
200 	int o2dlm_mode = mode_to_o2dlm(mode);
201 	int o2dlm_flags = flags_to_o2dlm(flags);
202 	int ret;
203 
204 	status = dlmlock(conn->cc_lockspace, o2dlm_mode, &lksb->lksb_o2dlm,
205 			 o2dlm_flags, name, namelen,
206 			 o2dlm_lock_ast_wrapper, lksb,
207 			 o2dlm_blocking_ast_wrapper);
208 	ret = dlm_status_to_errno(status);
209 	return ret;
210 }
211 
212 static int o2cb_dlm_unlock(struct ocfs2_cluster_connection *conn,
213 			   struct ocfs2_dlm_lksb *lksb,
214 			   u32 flags)
215 {
216 	enum dlm_status status;
217 	int o2dlm_flags = flags_to_o2dlm(flags);
218 	int ret;
219 
220 	status = dlmunlock(conn->cc_lockspace, &lksb->lksb_o2dlm,
221 			   o2dlm_flags, o2dlm_unlock_ast_wrapper, lksb);
222 	ret = dlm_status_to_errno(status);
223 	return ret;
224 }
225 
226 static int o2cb_dlm_lock_status(struct ocfs2_dlm_lksb *lksb)
227 {
228 	return dlm_status_to_errno(lksb->lksb_o2dlm.status);
229 }
230 
231 /*
232  * o2dlm aways has a "valid" LVB. If the dlm loses track of the LVB
233  * contents, it will zero out the LVB.  Thus the caller can always trust
234  * the contents.
235  */
236 static int o2cb_dlm_lvb_valid(struct ocfs2_dlm_lksb *lksb)
237 {
238 	return 1;
239 }
240 
241 static void *o2cb_dlm_lvb(struct ocfs2_dlm_lksb *lksb)
242 {
243 	return (void *)(lksb->lksb_o2dlm.lvb);
244 }
245 
246 static void o2cb_dump_lksb(struct ocfs2_dlm_lksb *lksb)
247 {
248 	dlm_print_one_lock(lksb->lksb_o2dlm.lockid);
249 }
250 
251 /*
252  * Check if this node is heartbeating and is connected to all other
253  * heartbeating nodes.
254  */
255 static int o2cb_cluster_check(void)
256 {
257 	u8 node_num;
258 	int i;
259 	unsigned long hbmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
260 	unsigned long netmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
261 
262 	node_num = o2nm_this_node();
263 	if (node_num == O2NM_MAX_NODES) {
264 		printk(KERN_ERR "o2cb: This node has not been configured.\n");
265 		return -EINVAL;
266 	}
267 
268 	/*
269 	 * o2dlm expects o2net sockets to be created. If not, then
270 	 * dlm_join_domain() fails with a stack of errors which are both cryptic
271 	 * and incomplete. The idea here is to detect upfront whether we have
272 	 * managed to connect to all nodes or not. If not, then list the nodes
273 	 * to allow the user to check the configuration (incorrect IP, firewall,
274 	 * etc.) Yes, this is racy. But its not the end of the world.
275 	 */
276 #define	O2CB_MAP_STABILIZE_COUNT	60
277 	for (i = 0; i < O2CB_MAP_STABILIZE_COUNT; ++i) {
278 		o2hb_fill_node_map(hbmap, sizeof(hbmap));
279 		if (!test_bit(node_num, hbmap)) {
280 			printk(KERN_ERR "o2cb: %s heartbeat has not been "
281 			       "started.\n", (o2hb_global_heartbeat_active() ?
282 					      "Global" : "Local"));
283 			return -EINVAL;
284 		}
285 		o2net_fill_node_map(netmap, sizeof(netmap));
286 		/* Force set the current node to allow easy compare */
287 		set_bit(node_num, netmap);
288 		if (!memcmp(hbmap, netmap, sizeof(hbmap)))
289 			return 0;
290 		if (i < O2CB_MAP_STABILIZE_COUNT - 1)
291 			msleep(1000);
292 	}
293 
294 	printk(KERN_ERR "o2cb: This node could not connect to nodes:");
295 	i = -1;
296 	while ((i = find_next_bit(hbmap, O2NM_MAX_NODES,
297 				  i + 1)) < O2NM_MAX_NODES) {
298 		if (!test_bit(i, netmap))
299 			printk(" %u", i);
300 	}
301 	printk(".\n");
302 
303 	return -ENOTCONN;
304 }
305 
306 /*
307  * Called from the dlm when it's about to evict a node. This is how the
308  * classic stack signals node death.
309  */
310 static void o2dlm_eviction_cb(int node_num, void *data)
311 {
312 	struct ocfs2_cluster_connection *conn = data;
313 
314 	printk(KERN_NOTICE "o2cb: o2dlm has evicted node %d from domain %.*s\n",
315 	       node_num, conn->cc_namelen, conn->cc_name);
316 
317 	conn->cc_recovery_handler(node_num, conn->cc_recovery_data);
318 }
319 
320 static int o2cb_cluster_connect(struct ocfs2_cluster_connection *conn)
321 {
322 	int rc = 0;
323 	u32 dlm_key;
324 	struct dlm_ctxt *dlm;
325 	struct o2dlm_private *priv;
326 	struct dlm_protocol_version fs_version;
327 
328 	BUG_ON(conn == NULL);
329 	BUG_ON(conn->cc_proto == NULL);
330 
331 	/* Ensure cluster stack is up and all nodes are connected */
332 	rc = o2cb_cluster_check();
333 	if (rc) {
334 		printk(KERN_ERR "o2cb: Cluster check failed. Fix errors "
335 		       "before retrying.\n");
336 		goto out;
337 	}
338 
339 	priv = kzalloc(sizeof(struct o2dlm_private), GFP_KERNEL);
340 	if (!priv) {
341 		rc = -ENOMEM;
342 		goto out_free;
343 	}
344 
345 	/* This just fills the structure in.  It is safe to pass conn. */
346 	dlm_setup_eviction_cb(&priv->op_eviction_cb, o2dlm_eviction_cb,
347 			      conn);
348 
349 	conn->cc_private = priv;
350 
351 	/* used by the dlm code to make message headers unique, each
352 	 * node in this domain must agree on this. */
353 	dlm_key = crc32_le(0, conn->cc_name, conn->cc_namelen);
354 	fs_version.pv_major = conn->cc_version.pv_major;
355 	fs_version.pv_minor = conn->cc_version.pv_minor;
356 
357 	dlm = dlm_register_domain(conn->cc_name, dlm_key, &fs_version);
358 	if (IS_ERR(dlm)) {
359 		rc = PTR_ERR(dlm);
360 		mlog_errno(rc);
361 		goto out_free;
362 	}
363 
364 	conn->cc_version.pv_major = fs_version.pv_major;
365 	conn->cc_version.pv_minor = fs_version.pv_minor;
366 	conn->cc_lockspace = dlm;
367 
368 	dlm_register_eviction_cb(dlm, &priv->op_eviction_cb);
369 
370 out_free:
371 	if (rc)
372 		kfree(conn->cc_private);
373 
374 out:
375 	return rc;
376 }
377 
378 static int o2cb_cluster_disconnect(struct ocfs2_cluster_connection *conn)
379 {
380 	struct dlm_ctxt *dlm = conn->cc_lockspace;
381 	struct o2dlm_private *priv = conn->cc_private;
382 
383 	dlm_unregister_eviction_cb(&priv->op_eviction_cb);
384 	conn->cc_private = NULL;
385 	kfree(priv);
386 
387 	dlm_unregister_domain(dlm);
388 	conn->cc_lockspace = NULL;
389 
390 	return 0;
391 }
392 
393 static int o2cb_cluster_this_node(struct ocfs2_cluster_connection *conn,
394 				  unsigned int *node)
395 {
396 	int node_num;
397 
398 	node_num = o2nm_this_node();
399 	if (node_num == O2NM_INVALID_NODE_NUM)
400 		return -ENOENT;
401 
402 	if (node_num >= O2NM_MAX_NODES)
403 		return -EOVERFLOW;
404 
405 	*node = node_num;
406 	return 0;
407 }
408 
409 static struct ocfs2_stack_operations o2cb_stack_ops = {
410 	.connect	= o2cb_cluster_connect,
411 	.disconnect	= o2cb_cluster_disconnect,
412 	.this_node	= o2cb_cluster_this_node,
413 	.dlm_lock	= o2cb_dlm_lock,
414 	.dlm_unlock	= o2cb_dlm_unlock,
415 	.lock_status	= o2cb_dlm_lock_status,
416 	.lvb_valid	= o2cb_dlm_lvb_valid,
417 	.lock_lvb	= o2cb_dlm_lvb,
418 	.dump_lksb	= o2cb_dump_lksb,
419 };
420 
421 static struct ocfs2_stack_plugin o2cb_stack = {
422 	.sp_name	= "o2cb",
423 	.sp_ops		= &o2cb_stack_ops,
424 	.sp_owner	= THIS_MODULE,
425 };
426 
427 static int __init o2cb_stack_init(void)
428 {
429 	return ocfs2_stack_glue_register(&o2cb_stack);
430 }
431 
432 static void __exit o2cb_stack_exit(void)
433 {
434 	ocfs2_stack_glue_unregister(&o2cb_stack);
435 }
436 
437 MODULE_AUTHOR("Oracle");
438 MODULE_DESCRIPTION("ocfs2 driver for the classic o2cb stack");
439 MODULE_LICENSE("GPL");
440 module_init(o2cb_stack_init);
441 module_exit(o2cb_stack_exit);
442