xref: /openbmc/linux/fs/dlm/config.c (revision 95e9fd10)
1 /******************************************************************************
2 *******************************************************************************
3 **
4 **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
5 **  Copyright (C) 2004-2011 Red Hat, Inc.  All rights reserved.
6 **
7 **  This copyrighted material is made available to anyone wishing to use,
8 **  modify, copy, or redistribute it subject to the terms and conditions
9 **  of the GNU General Public License v.2.
10 **
11 *******************************************************************************
12 ******************************************************************************/
13 
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/configfs.h>
17 #include <linux/slab.h>
18 #include <linux/in.h>
19 #include <linux/in6.h>
20 #include <linux/dlmconstants.h>
21 #include <net/ipv6.h>
22 #include <net/sock.h>
23 
24 #include "config.h"
25 #include "lowcomms.h"
26 
27 /*
28  * /config/dlm/<cluster>/spaces/<space>/nodes/<node>/nodeid
29  * /config/dlm/<cluster>/spaces/<space>/nodes/<node>/weight
30  * /config/dlm/<cluster>/comms/<comm>/nodeid
31  * /config/dlm/<cluster>/comms/<comm>/local
32  * /config/dlm/<cluster>/comms/<comm>/addr      (write only)
33  * /config/dlm/<cluster>/comms/<comm>/addr_list (read only)
34  * The <cluster> level is useless, but I haven't figured out how to avoid it.
35  */
36 
37 static struct config_group *space_list;
38 static struct config_group *comm_list;
39 static struct dlm_comm *local_comm;
40 static uint32_t dlm_comm_count;
41 
42 struct dlm_clusters;
43 struct dlm_cluster;
44 struct dlm_spaces;
45 struct dlm_space;
46 struct dlm_comms;
47 struct dlm_comm;
48 struct dlm_nodes;
49 struct dlm_node;
50 
51 static struct config_group *make_cluster(struct config_group *, const char *);
52 static void drop_cluster(struct config_group *, struct config_item *);
53 static void release_cluster(struct config_item *);
54 static struct config_group *make_space(struct config_group *, const char *);
55 static void drop_space(struct config_group *, struct config_item *);
56 static void release_space(struct config_item *);
57 static struct config_item *make_comm(struct config_group *, const char *);
58 static void drop_comm(struct config_group *, struct config_item *);
59 static void release_comm(struct config_item *);
60 static struct config_item *make_node(struct config_group *, const char *);
61 static void drop_node(struct config_group *, struct config_item *);
62 static void release_node(struct config_item *);
63 
64 static ssize_t show_cluster(struct config_item *i, struct configfs_attribute *a,
65 			    char *buf);
66 static ssize_t store_cluster(struct config_item *i,
67 			     struct configfs_attribute *a,
68 			     const char *buf, size_t len);
69 static ssize_t show_comm(struct config_item *i, struct configfs_attribute *a,
70 			 char *buf);
71 static ssize_t store_comm(struct config_item *i, struct configfs_attribute *a,
72 			  const char *buf, size_t len);
73 static ssize_t show_node(struct config_item *i, struct configfs_attribute *a,
74 			 char *buf);
75 static ssize_t store_node(struct config_item *i, struct configfs_attribute *a,
76 			  const char *buf, size_t len);
77 
78 static ssize_t comm_nodeid_read(struct dlm_comm *cm, char *buf);
79 static ssize_t comm_nodeid_write(struct dlm_comm *cm, const char *buf,
80 				size_t len);
81 static ssize_t comm_local_read(struct dlm_comm *cm, char *buf);
82 static ssize_t comm_local_write(struct dlm_comm *cm, const char *buf,
83 				size_t len);
84 static ssize_t comm_addr_write(struct dlm_comm *cm, const char *buf,
85 				size_t len);
86 static ssize_t comm_addr_list_read(struct dlm_comm *cm, char *buf);
87 static ssize_t node_nodeid_read(struct dlm_node *nd, char *buf);
88 static ssize_t node_nodeid_write(struct dlm_node *nd, const char *buf,
89 				size_t len);
90 static ssize_t node_weight_read(struct dlm_node *nd, char *buf);
91 static ssize_t node_weight_write(struct dlm_node *nd, const char *buf,
92 				size_t len);
93 
94 struct dlm_cluster {
95 	struct config_group group;
96 	unsigned int cl_tcp_port;
97 	unsigned int cl_buffer_size;
98 	unsigned int cl_rsbtbl_size;
99 	unsigned int cl_recover_timer;
100 	unsigned int cl_toss_secs;
101 	unsigned int cl_scan_secs;
102 	unsigned int cl_log_debug;
103 	unsigned int cl_protocol;
104 	unsigned int cl_timewarn_cs;
105 	unsigned int cl_waitwarn_us;
106 	unsigned int cl_new_rsb_count;
107 	unsigned int cl_recover_callbacks;
108 	char cl_cluster_name[DLM_LOCKSPACE_LEN];
109 };
110 
111 enum {
112 	CLUSTER_ATTR_TCP_PORT = 0,
113 	CLUSTER_ATTR_BUFFER_SIZE,
114 	CLUSTER_ATTR_RSBTBL_SIZE,
115 	CLUSTER_ATTR_RECOVER_TIMER,
116 	CLUSTER_ATTR_TOSS_SECS,
117 	CLUSTER_ATTR_SCAN_SECS,
118 	CLUSTER_ATTR_LOG_DEBUG,
119 	CLUSTER_ATTR_PROTOCOL,
120 	CLUSTER_ATTR_TIMEWARN_CS,
121 	CLUSTER_ATTR_WAITWARN_US,
122 	CLUSTER_ATTR_NEW_RSB_COUNT,
123 	CLUSTER_ATTR_RECOVER_CALLBACKS,
124 	CLUSTER_ATTR_CLUSTER_NAME,
125 };
126 
127 struct cluster_attribute {
128 	struct configfs_attribute attr;
129 	ssize_t (*show)(struct dlm_cluster *, char *);
130 	ssize_t (*store)(struct dlm_cluster *, const char *, size_t);
131 };
132 
133 static ssize_t cluster_cluster_name_read(struct dlm_cluster *cl, char *buf)
134 {
135 	return sprintf(buf, "%s\n", cl->cl_cluster_name);
136 }
137 
138 static ssize_t cluster_cluster_name_write(struct dlm_cluster *cl,
139 					  const char *buf, size_t len)
140 {
141 	strncpy(dlm_config.ci_cluster_name, buf, DLM_LOCKSPACE_LEN);
142 	strncpy(cl->cl_cluster_name, buf, DLM_LOCKSPACE_LEN);
143 	return len;
144 }
145 
146 static struct cluster_attribute cluster_attr_cluster_name = {
147 	.attr   = { .ca_owner = THIS_MODULE,
148                     .ca_name = "cluster_name",
149                     .ca_mode = S_IRUGO | S_IWUSR },
150 	.show   = cluster_cluster_name_read,
151 	.store  = cluster_cluster_name_write,
152 };
153 
154 static ssize_t cluster_set(struct dlm_cluster *cl, unsigned int *cl_field,
155 			   int *info_field, int check_zero,
156 			   const char *buf, size_t len)
157 {
158 	unsigned int x;
159 
160 	if (!capable(CAP_SYS_ADMIN))
161 		return -EACCES;
162 
163 	x = simple_strtoul(buf, NULL, 0);
164 
165 	if (check_zero && !x)
166 		return -EINVAL;
167 
168 	*cl_field = x;
169 	*info_field = x;
170 
171 	return len;
172 }
173 
174 #define CLUSTER_ATTR(name, check_zero)                                        \
175 static ssize_t name##_write(struct dlm_cluster *cl, const char *buf, size_t len) \
176 {                                                                             \
177 	return cluster_set(cl, &cl->cl_##name, &dlm_config.ci_##name,         \
178 			   check_zero, buf, len);                             \
179 }                                                                             \
180 static ssize_t name##_read(struct dlm_cluster *cl, char *buf)                 \
181 {                                                                             \
182 	return snprintf(buf, PAGE_SIZE, "%u\n", cl->cl_##name);               \
183 }                                                                             \
184 static struct cluster_attribute cluster_attr_##name =                         \
185 __CONFIGFS_ATTR(name, 0644, name##_read, name##_write)
186 
187 CLUSTER_ATTR(tcp_port, 1);
188 CLUSTER_ATTR(buffer_size, 1);
189 CLUSTER_ATTR(rsbtbl_size, 1);
190 CLUSTER_ATTR(recover_timer, 1);
191 CLUSTER_ATTR(toss_secs, 1);
192 CLUSTER_ATTR(scan_secs, 1);
193 CLUSTER_ATTR(log_debug, 0);
194 CLUSTER_ATTR(protocol, 0);
195 CLUSTER_ATTR(timewarn_cs, 1);
196 CLUSTER_ATTR(waitwarn_us, 0);
197 CLUSTER_ATTR(new_rsb_count, 0);
198 CLUSTER_ATTR(recover_callbacks, 0);
199 
200 static struct configfs_attribute *cluster_attrs[] = {
201 	[CLUSTER_ATTR_TCP_PORT] = &cluster_attr_tcp_port.attr,
202 	[CLUSTER_ATTR_BUFFER_SIZE] = &cluster_attr_buffer_size.attr,
203 	[CLUSTER_ATTR_RSBTBL_SIZE] = &cluster_attr_rsbtbl_size.attr,
204 	[CLUSTER_ATTR_RECOVER_TIMER] = &cluster_attr_recover_timer.attr,
205 	[CLUSTER_ATTR_TOSS_SECS] = &cluster_attr_toss_secs.attr,
206 	[CLUSTER_ATTR_SCAN_SECS] = &cluster_attr_scan_secs.attr,
207 	[CLUSTER_ATTR_LOG_DEBUG] = &cluster_attr_log_debug.attr,
208 	[CLUSTER_ATTR_PROTOCOL] = &cluster_attr_protocol.attr,
209 	[CLUSTER_ATTR_TIMEWARN_CS] = &cluster_attr_timewarn_cs.attr,
210 	[CLUSTER_ATTR_WAITWARN_US] = &cluster_attr_waitwarn_us.attr,
211 	[CLUSTER_ATTR_NEW_RSB_COUNT] = &cluster_attr_new_rsb_count.attr,
212 	[CLUSTER_ATTR_RECOVER_CALLBACKS] = &cluster_attr_recover_callbacks.attr,
213 	[CLUSTER_ATTR_CLUSTER_NAME] = &cluster_attr_cluster_name.attr,
214 	NULL,
215 };
216 
217 enum {
218 	COMM_ATTR_NODEID = 0,
219 	COMM_ATTR_LOCAL,
220 	COMM_ATTR_ADDR,
221 	COMM_ATTR_ADDR_LIST,
222 };
223 
224 struct comm_attribute {
225 	struct configfs_attribute attr;
226 	ssize_t (*show)(struct dlm_comm *, char *);
227 	ssize_t (*store)(struct dlm_comm *, const char *, size_t);
228 };
229 
230 static struct comm_attribute comm_attr_nodeid = {
231 	.attr   = { .ca_owner = THIS_MODULE,
232                     .ca_name = "nodeid",
233                     .ca_mode = S_IRUGO | S_IWUSR },
234 	.show   = comm_nodeid_read,
235 	.store  = comm_nodeid_write,
236 };
237 
238 static struct comm_attribute comm_attr_local = {
239 	.attr   = { .ca_owner = THIS_MODULE,
240                     .ca_name = "local",
241                     .ca_mode = S_IRUGO | S_IWUSR },
242 	.show   = comm_local_read,
243 	.store  = comm_local_write,
244 };
245 
246 static struct comm_attribute comm_attr_addr = {
247 	.attr   = { .ca_owner = THIS_MODULE,
248                     .ca_name = "addr",
249                     .ca_mode = S_IWUSR },
250 	.store  = comm_addr_write,
251 };
252 
253 static struct comm_attribute comm_attr_addr_list = {
254 	.attr   = { .ca_owner = THIS_MODULE,
255                     .ca_name = "addr_list",
256                     .ca_mode = S_IRUGO },
257 	.show   = comm_addr_list_read,
258 };
259 
260 static struct configfs_attribute *comm_attrs[] = {
261 	[COMM_ATTR_NODEID] = &comm_attr_nodeid.attr,
262 	[COMM_ATTR_LOCAL] = &comm_attr_local.attr,
263 	[COMM_ATTR_ADDR] = &comm_attr_addr.attr,
264 	[COMM_ATTR_ADDR_LIST] = &comm_attr_addr_list.attr,
265 	NULL,
266 };
267 
268 enum {
269 	NODE_ATTR_NODEID = 0,
270 	NODE_ATTR_WEIGHT,
271 };
272 
273 struct node_attribute {
274 	struct configfs_attribute attr;
275 	ssize_t (*show)(struct dlm_node *, char *);
276 	ssize_t (*store)(struct dlm_node *, const char *, size_t);
277 };
278 
279 static struct node_attribute node_attr_nodeid = {
280 	.attr   = { .ca_owner = THIS_MODULE,
281                     .ca_name = "nodeid",
282                     .ca_mode = S_IRUGO | S_IWUSR },
283 	.show   = node_nodeid_read,
284 	.store  = node_nodeid_write,
285 };
286 
287 static struct node_attribute node_attr_weight = {
288 	.attr   = { .ca_owner = THIS_MODULE,
289                     .ca_name = "weight",
290                     .ca_mode = S_IRUGO | S_IWUSR },
291 	.show   = node_weight_read,
292 	.store  = node_weight_write,
293 };
294 
295 static struct configfs_attribute *node_attrs[] = {
296 	[NODE_ATTR_NODEID] = &node_attr_nodeid.attr,
297 	[NODE_ATTR_WEIGHT] = &node_attr_weight.attr,
298 	NULL,
299 };
300 
301 struct dlm_clusters {
302 	struct configfs_subsystem subsys;
303 };
304 
305 struct dlm_spaces {
306 	struct config_group ss_group;
307 };
308 
309 struct dlm_space {
310 	struct config_group group;
311 	struct list_head members;
312 	struct mutex members_lock;
313 	int members_count;
314 };
315 
316 struct dlm_comms {
317 	struct config_group cs_group;
318 };
319 
320 struct dlm_comm {
321 	struct config_item item;
322 	int seq;
323 	int nodeid;
324 	int local;
325 	int addr_count;
326 	struct sockaddr_storage *addr[DLM_MAX_ADDR_COUNT];
327 };
328 
329 struct dlm_nodes {
330 	struct config_group ns_group;
331 };
332 
333 struct dlm_node {
334 	struct config_item item;
335 	struct list_head list; /* space->members */
336 	int nodeid;
337 	int weight;
338 	int new;
339 	int comm_seq; /* copy of cm->seq when nd->nodeid is set */
340 };
341 
342 static struct configfs_group_operations clusters_ops = {
343 	.make_group = make_cluster,
344 	.drop_item = drop_cluster,
345 };
346 
347 static struct configfs_item_operations cluster_ops = {
348 	.release = release_cluster,
349 	.show_attribute = show_cluster,
350 	.store_attribute = store_cluster,
351 };
352 
353 static struct configfs_group_operations spaces_ops = {
354 	.make_group = make_space,
355 	.drop_item = drop_space,
356 };
357 
358 static struct configfs_item_operations space_ops = {
359 	.release = release_space,
360 };
361 
362 static struct configfs_group_operations comms_ops = {
363 	.make_item = make_comm,
364 	.drop_item = drop_comm,
365 };
366 
367 static struct configfs_item_operations comm_ops = {
368 	.release = release_comm,
369 	.show_attribute = show_comm,
370 	.store_attribute = store_comm,
371 };
372 
373 static struct configfs_group_operations nodes_ops = {
374 	.make_item = make_node,
375 	.drop_item = drop_node,
376 };
377 
378 static struct configfs_item_operations node_ops = {
379 	.release = release_node,
380 	.show_attribute = show_node,
381 	.store_attribute = store_node,
382 };
383 
384 static struct config_item_type clusters_type = {
385 	.ct_group_ops = &clusters_ops,
386 	.ct_owner = THIS_MODULE,
387 };
388 
389 static struct config_item_type cluster_type = {
390 	.ct_item_ops = &cluster_ops,
391 	.ct_attrs = cluster_attrs,
392 	.ct_owner = THIS_MODULE,
393 };
394 
395 static struct config_item_type spaces_type = {
396 	.ct_group_ops = &spaces_ops,
397 	.ct_owner = THIS_MODULE,
398 };
399 
400 static struct config_item_type space_type = {
401 	.ct_item_ops = &space_ops,
402 	.ct_owner = THIS_MODULE,
403 };
404 
405 static struct config_item_type comms_type = {
406 	.ct_group_ops = &comms_ops,
407 	.ct_owner = THIS_MODULE,
408 };
409 
410 static struct config_item_type comm_type = {
411 	.ct_item_ops = &comm_ops,
412 	.ct_attrs = comm_attrs,
413 	.ct_owner = THIS_MODULE,
414 };
415 
416 static struct config_item_type nodes_type = {
417 	.ct_group_ops = &nodes_ops,
418 	.ct_owner = THIS_MODULE,
419 };
420 
421 static struct config_item_type node_type = {
422 	.ct_item_ops = &node_ops,
423 	.ct_attrs = node_attrs,
424 	.ct_owner = THIS_MODULE,
425 };
426 
427 static struct dlm_cluster *config_item_to_cluster(struct config_item *i)
428 {
429 	return i ? container_of(to_config_group(i), struct dlm_cluster, group) :
430 		   NULL;
431 }
432 
433 static struct dlm_space *config_item_to_space(struct config_item *i)
434 {
435 	return i ? container_of(to_config_group(i), struct dlm_space, group) :
436 		   NULL;
437 }
438 
439 static struct dlm_comm *config_item_to_comm(struct config_item *i)
440 {
441 	return i ? container_of(i, struct dlm_comm, item) : NULL;
442 }
443 
444 static struct dlm_node *config_item_to_node(struct config_item *i)
445 {
446 	return i ? container_of(i, struct dlm_node, item) : NULL;
447 }
448 
449 static struct config_group *make_cluster(struct config_group *g,
450 					 const char *name)
451 {
452 	struct dlm_cluster *cl = NULL;
453 	struct dlm_spaces *sps = NULL;
454 	struct dlm_comms *cms = NULL;
455 	void *gps = NULL;
456 
457 	cl = kzalloc(sizeof(struct dlm_cluster), GFP_NOFS);
458 	gps = kcalloc(3, sizeof(struct config_group *), GFP_NOFS);
459 	sps = kzalloc(sizeof(struct dlm_spaces), GFP_NOFS);
460 	cms = kzalloc(sizeof(struct dlm_comms), GFP_NOFS);
461 
462 	if (!cl || !gps || !sps || !cms)
463 		goto fail;
464 
465 	config_group_init_type_name(&cl->group, name, &cluster_type);
466 	config_group_init_type_name(&sps->ss_group, "spaces", &spaces_type);
467 	config_group_init_type_name(&cms->cs_group, "comms", &comms_type);
468 
469 	cl->group.default_groups = gps;
470 	cl->group.default_groups[0] = &sps->ss_group;
471 	cl->group.default_groups[1] = &cms->cs_group;
472 	cl->group.default_groups[2] = NULL;
473 
474 	cl->cl_tcp_port = dlm_config.ci_tcp_port;
475 	cl->cl_buffer_size = dlm_config.ci_buffer_size;
476 	cl->cl_rsbtbl_size = dlm_config.ci_rsbtbl_size;
477 	cl->cl_recover_timer = dlm_config.ci_recover_timer;
478 	cl->cl_toss_secs = dlm_config.ci_toss_secs;
479 	cl->cl_scan_secs = dlm_config.ci_scan_secs;
480 	cl->cl_log_debug = dlm_config.ci_log_debug;
481 	cl->cl_protocol = dlm_config.ci_protocol;
482 	cl->cl_timewarn_cs = dlm_config.ci_timewarn_cs;
483 	cl->cl_waitwarn_us = dlm_config.ci_waitwarn_us;
484 	cl->cl_new_rsb_count = dlm_config.ci_new_rsb_count;
485 	cl->cl_recover_callbacks = dlm_config.ci_recover_callbacks;
486 	memcpy(cl->cl_cluster_name, dlm_config.ci_cluster_name,
487 	       DLM_LOCKSPACE_LEN);
488 
489 	space_list = &sps->ss_group;
490 	comm_list = &cms->cs_group;
491 	return &cl->group;
492 
493  fail:
494 	kfree(cl);
495 	kfree(gps);
496 	kfree(sps);
497 	kfree(cms);
498 	return ERR_PTR(-ENOMEM);
499 }
500 
501 static void drop_cluster(struct config_group *g, struct config_item *i)
502 {
503 	struct dlm_cluster *cl = config_item_to_cluster(i);
504 	struct config_item *tmp;
505 	int j;
506 
507 	for (j = 0; cl->group.default_groups[j]; j++) {
508 		tmp = &cl->group.default_groups[j]->cg_item;
509 		cl->group.default_groups[j] = NULL;
510 		config_item_put(tmp);
511 	}
512 
513 	space_list = NULL;
514 	comm_list = NULL;
515 
516 	config_item_put(i);
517 }
518 
519 static void release_cluster(struct config_item *i)
520 {
521 	struct dlm_cluster *cl = config_item_to_cluster(i);
522 	kfree(cl->group.default_groups);
523 	kfree(cl);
524 }
525 
526 static struct config_group *make_space(struct config_group *g, const char *name)
527 {
528 	struct dlm_space *sp = NULL;
529 	struct dlm_nodes *nds = NULL;
530 	void *gps = NULL;
531 
532 	sp = kzalloc(sizeof(struct dlm_space), GFP_NOFS);
533 	gps = kcalloc(2, sizeof(struct config_group *), GFP_NOFS);
534 	nds = kzalloc(sizeof(struct dlm_nodes), GFP_NOFS);
535 
536 	if (!sp || !gps || !nds)
537 		goto fail;
538 
539 	config_group_init_type_name(&sp->group, name, &space_type);
540 	config_group_init_type_name(&nds->ns_group, "nodes", &nodes_type);
541 
542 	sp->group.default_groups = gps;
543 	sp->group.default_groups[0] = &nds->ns_group;
544 	sp->group.default_groups[1] = NULL;
545 
546 	INIT_LIST_HEAD(&sp->members);
547 	mutex_init(&sp->members_lock);
548 	sp->members_count = 0;
549 	return &sp->group;
550 
551  fail:
552 	kfree(sp);
553 	kfree(gps);
554 	kfree(nds);
555 	return ERR_PTR(-ENOMEM);
556 }
557 
558 static void drop_space(struct config_group *g, struct config_item *i)
559 {
560 	struct dlm_space *sp = config_item_to_space(i);
561 	struct config_item *tmp;
562 	int j;
563 
564 	/* assert list_empty(&sp->members) */
565 
566 	for (j = 0; sp->group.default_groups[j]; j++) {
567 		tmp = &sp->group.default_groups[j]->cg_item;
568 		sp->group.default_groups[j] = NULL;
569 		config_item_put(tmp);
570 	}
571 
572 	config_item_put(i);
573 }
574 
575 static void release_space(struct config_item *i)
576 {
577 	struct dlm_space *sp = config_item_to_space(i);
578 	kfree(sp->group.default_groups);
579 	kfree(sp);
580 }
581 
582 static struct config_item *make_comm(struct config_group *g, const char *name)
583 {
584 	struct dlm_comm *cm;
585 
586 	cm = kzalloc(sizeof(struct dlm_comm), GFP_NOFS);
587 	if (!cm)
588 		return ERR_PTR(-ENOMEM);
589 
590 	config_item_init_type_name(&cm->item, name, &comm_type);
591 
592 	cm->seq = dlm_comm_count++;
593 	if (!cm->seq)
594 		cm->seq = dlm_comm_count++;
595 
596 	cm->nodeid = -1;
597 	cm->local = 0;
598 	cm->addr_count = 0;
599 	return &cm->item;
600 }
601 
602 static void drop_comm(struct config_group *g, struct config_item *i)
603 {
604 	struct dlm_comm *cm = config_item_to_comm(i);
605 	if (local_comm == cm)
606 		local_comm = NULL;
607 	dlm_lowcomms_close(cm->nodeid);
608 	while (cm->addr_count--)
609 		kfree(cm->addr[cm->addr_count]);
610 	config_item_put(i);
611 }
612 
613 static void release_comm(struct config_item *i)
614 {
615 	struct dlm_comm *cm = config_item_to_comm(i);
616 	kfree(cm);
617 }
618 
619 static struct config_item *make_node(struct config_group *g, const char *name)
620 {
621 	struct dlm_space *sp = config_item_to_space(g->cg_item.ci_parent);
622 	struct dlm_node *nd;
623 
624 	nd = kzalloc(sizeof(struct dlm_node), GFP_NOFS);
625 	if (!nd)
626 		return ERR_PTR(-ENOMEM);
627 
628 	config_item_init_type_name(&nd->item, name, &node_type);
629 	nd->nodeid = -1;
630 	nd->weight = 1;  /* default weight of 1 if none is set */
631 	nd->new = 1;     /* set to 0 once it's been read by dlm_nodeid_list() */
632 
633 	mutex_lock(&sp->members_lock);
634 	list_add(&nd->list, &sp->members);
635 	sp->members_count++;
636 	mutex_unlock(&sp->members_lock);
637 
638 	return &nd->item;
639 }
640 
641 static void drop_node(struct config_group *g, struct config_item *i)
642 {
643 	struct dlm_space *sp = config_item_to_space(g->cg_item.ci_parent);
644 	struct dlm_node *nd = config_item_to_node(i);
645 
646 	mutex_lock(&sp->members_lock);
647 	list_del(&nd->list);
648 	sp->members_count--;
649 	mutex_unlock(&sp->members_lock);
650 
651 	config_item_put(i);
652 }
653 
654 static void release_node(struct config_item *i)
655 {
656 	struct dlm_node *nd = config_item_to_node(i);
657 	kfree(nd);
658 }
659 
660 static struct dlm_clusters clusters_root = {
661 	.subsys = {
662 		.su_group = {
663 			.cg_item = {
664 				.ci_namebuf = "dlm",
665 				.ci_type = &clusters_type,
666 			},
667 		},
668 	},
669 };
670 
671 int __init dlm_config_init(void)
672 {
673 	config_group_init(&clusters_root.subsys.su_group);
674 	mutex_init(&clusters_root.subsys.su_mutex);
675 	return configfs_register_subsystem(&clusters_root.subsys);
676 }
677 
678 void dlm_config_exit(void)
679 {
680 	configfs_unregister_subsystem(&clusters_root.subsys);
681 }
682 
683 /*
684  * Functions for user space to read/write attributes
685  */
686 
687 static ssize_t show_cluster(struct config_item *i, struct configfs_attribute *a,
688 			    char *buf)
689 {
690 	struct dlm_cluster *cl = config_item_to_cluster(i);
691 	struct cluster_attribute *cla =
692 			container_of(a, struct cluster_attribute, attr);
693 	return cla->show ? cla->show(cl, buf) : 0;
694 }
695 
696 static ssize_t store_cluster(struct config_item *i,
697 			     struct configfs_attribute *a,
698 			     const char *buf, size_t len)
699 {
700 	struct dlm_cluster *cl = config_item_to_cluster(i);
701 	struct cluster_attribute *cla =
702 		container_of(a, struct cluster_attribute, attr);
703 	return cla->store ? cla->store(cl, buf, len) : -EINVAL;
704 }
705 
706 static ssize_t show_comm(struct config_item *i, struct configfs_attribute *a,
707 			 char *buf)
708 {
709 	struct dlm_comm *cm = config_item_to_comm(i);
710 	struct comm_attribute *cma =
711 			container_of(a, struct comm_attribute, attr);
712 	return cma->show ? cma->show(cm, buf) : 0;
713 }
714 
715 static ssize_t store_comm(struct config_item *i, struct configfs_attribute *a,
716 			  const char *buf, size_t len)
717 {
718 	struct dlm_comm *cm = config_item_to_comm(i);
719 	struct comm_attribute *cma =
720 		container_of(a, struct comm_attribute, attr);
721 	return cma->store ? cma->store(cm, buf, len) : -EINVAL;
722 }
723 
724 static ssize_t comm_nodeid_read(struct dlm_comm *cm, char *buf)
725 {
726 	return sprintf(buf, "%d\n", cm->nodeid);
727 }
728 
729 static ssize_t comm_nodeid_write(struct dlm_comm *cm, const char *buf,
730 				 size_t len)
731 {
732 	cm->nodeid = simple_strtol(buf, NULL, 0);
733 	return len;
734 }
735 
736 static ssize_t comm_local_read(struct dlm_comm *cm, char *buf)
737 {
738 	return sprintf(buf, "%d\n", cm->local);
739 }
740 
741 static ssize_t comm_local_write(struct dlm_comm *cm, const char *buf,
742 				size_t len)
743 {
744 	cm->local= simple_strtol(buf, NULL, 0);
745 	if (cm->local && !local_comm)
746 		local_comm = cm;
747 	return len;
748 }
749 
750 static ssize_t comm_addr_write(struct dlm_comm *cm, const char *buf, size_t len)
751 {
752 	struct sockaddr_storage *addr;
753 
754 	if (len != sizeof(struct sockaddr_storage))
755 		return -EINVAL;
756 
757 	if (cm->addr_count >= DLM_MAX_ADDR_COUNT)
758 		return -ENOSPC;
759 
760 	addr = kzalloc(sizeof(*addr), GFP_NOFS);
761 	if (!addr)
762 		return -ENOMEM;
763 
764 	memcpy(addr, buf, len);
765 	cm->addr[cm->addr_count++] = addr;
766 	return len;
767 }
768 
769 static ssize_t comm_addr_list_read(struct dlm_comm *cm, char *buf)
770 {
771 	ssize_t s;
772 	ssize_t allowance;
773 	int i;
774 	struct sockaddr_storage *addr;
775 	struct sockaddr_in *addr_in;
776 	struct sockaddr_in6 *addr_in6;
777 
778 	/* Taken from ip6_addr_string() defined in lib/vsprintf.c */
779 	char buf0[sizeof("AF_INET6	xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255\n")];
780 
781 
782 	/* Derived from SIMPLE_ATTR_SIZE of fs/configfs/file.c */
783 	allowance = 4096;
784 	buf[0] = '\0';
785 
786 	for (i = 0; i < cm->addr_count; i++) {
787 		addr = cm->addr[i];
788 
789 		switch(addr->ss_family) {
790 		case AF_INET:
791 			addr_in = (struct sockaddr_in *)addr;
792 			s = sprintf(buf0, "AF_INET	%pI4\n", &addr_in->sin_addr.s_addr);
793 			break;
794 		case AF_INET6:
795 			addr_in6 = (struct sockaddr_in6 *)addr;
796 			s = sprintf(buf0, "AF_INET6	%pI6\n", &addr_in6->sin6_addr);
797 			break;
798 		default:
799 			s = sprintf(buf0, "%s\n", "<UNKNOWN>");
800 			break;
801 		}
802 		allowance -= s;
803 		if (allowance >= 0)
804 			strcat(buf, buf0);
805 		else {
806 			allowance += s;
807 			break;
808 		}
809 	}
810 	return 4096 - allowance;
811 }
812 
813 static ssize_t show_node(struct config_item *i, struct configfs_attribute *a,
814 			 char *buf)
815 {
816 	struct dlm_node *nd = config_item_to_node(i);
817 	struct node_attribute *nda =
818 			container_of(a, struct node_attribute, attr);
819 	return nda->show ? nda->show(nd, buf) : 0;
820 }
821 
822 static ssize_t store_node(struct config_item *i, struct configfs_attribute *a,
823 			  const char *buf, size_t len)
824 {
825 	struct dlm_node *nd = config_item_to_node(i);
826 	struct node_attribute *nda =
827 		container_of(a, struct node_attribute, attr);
828 	return nda->store ? nda->store(nd, buf, len) : -EINVAL;
829 }
830 
831 static ssize_t node_nodeid_read(struct dlm_node *nd, char *buf)
832 {
833 	return sprintf(buf, "%d\n", nd->nodeid);
834 }
835 
836 static ssize_t node_nodeid_write(struct dlm_node *nd, const char *buf,
837 				 size_t len)
838 {
839 	uint32_t seq = 0;
840 	nd->nodeid = simple_strtol(buf, NULL, 0);
841 	dlm_comm_seq(nd->nodeid, &seq);
842 	nd->comm_seq = seq;
843 	return len;
844 }
845 
846 static ssize_t node_weight_read(struct dlm_node *nd, char *buf)
847 {
848 	return sprintf(buf, "%d\n", nd->weight);
849 }
850 
851 static ssize_t node_weight_write(struct dlm_node *nd, const char *buf,
852 				 size_t len)
853 {
854 	nd->weight = simple_strtol(buf, NULL, 0);
855 	return len;
856 }
857 
858 /*
859  * Functions for the dlm to get the info that's been configured
860  */
861 
862 static struct dlm_space *get_space(char *name)
863 {
864 	struct config_item *i;
865 
866 	if (!space_list)
867 		return NULL;
868 
869 	mutex_lock(&space_list->cg_subsys->su_mutex);
870 	i = config_group_find_item(space_list, name);
871 	mutex_unlock(&space_list->cg_subsys->su_mutex);
872 
873 	return config_item_to_space(i);
874 }
875 
876 static void put_space(struct dlm_space *sp)
877 {
878 	config_item_put(&sp->group.cg_item);
879 }
880 
881 static int addr_compare(struct sockaddr_storage *x, struct sockaddr_storage *y)
882 {
883 	switch (x->ss_family) {
884 	case AF_INET: {
885 		struct sockaddr_in *sinx = (struct sockaddr_in *)x;
886 		struct sockaddr_in *siny = (struct sockaddr_in *)y;
887 		if (sinx->sin_addr.s_addr != siny->sin_addr.s_addr)
888 			return 0;
889 		if (sinx->sin_port != siny->sin_port)
890 			return 0;
891 		break;
892 	}
893 	case AF_INET6: {
894 		struct sockaddr_in6 *sinx = (struct sockaddr_in6 *)x;
895 		struct sockaddr_in6 *siny = (struct sockaddr_in6 *)y;
896 		if (!ipv6_addr_equal(&sinx->sin6_addr, &siny->sin6_addr))
897 			return 0;
898 		if (sinx->sin6_port != siny->sin6_port)
899 			return 0;
900 		break;
901 	}
902 	default:
903 		return 0;
904 	}
905 	return 1;
906 }
907 
908 static struct dlm_comm *get_comm(int nodeid, struct sockaddr_storage *addr)
909 {
910 	struct config_item *i;
911 	struct dlm_comm *cm = NULL;
912 	int found = 0;
913 
914 	if (!comm_list)
915 		return NULL;
916 
917 	mutex_lock(&clusters_root.subsys.su_mutex);
918 
919 	list_for_each_entry(i, &comm_list->cg_children, ci_entry) {
920 		cm = config_item_to_comm(i);
921 
922 		if (nodeid) {
923 			if (cm->nodeid != nodeid)
924 				continue;
925 			found = 1;
926 			config_item_get(i);
927 			break;
928 		} else {
929 			if (!cm->addr_count || !addr_compare(cm->addr[0], addr))
930 				continue;
931 			found = 1;
932 			config_item_get(i);
933 			break;
934 		}
935 	}
936 	mutex_unlock(&clusters_root.subsys.su_mutex);
937 
938 	if (!found)
939 		cm = NULL;
940 	return cm;
941 }
942 
943 static void put_comm(struct dlm_comm *cm)
944 {
945 	config_item_put(&cm->item);
946 }
947 
948 /* caller must free mem */
949 int dlm_config_nodes(char *lsname, struct dlm_config_node **nodes_out,
950 		     int *count_out)
951 {
952 	struct dlm_space *sp;
953 	struct dlm_node *nd;
954 	struct dlm_config_node *nodes, *node;
955 	int rv, count;
956 
957 	sp = get_space(lsname);
958 	if (!sp)
959 		return -EEXIST;
960 
961 	mutex_lock(&sp->members_lock);
962 	if (!sp->members_count) {
963 		rv = -EINVAL;
964 		printk(KERN_ERR "dlm: zero members_count\n");
965 		goto out;
966 	}
967 
968 	count = sp->members_count;
969 
970 	nodes = kcalloc(count, sizeof(struct dlm_config_node), GFP_NOFS);
971 	if (!nodes) {
972 		rv = -ENOMEM;
973 		goto out;
974 	}
975 
976 	node = nodes;
977 	list_for_each_entry(nd, &sp->members, list) {
978 		node->nodeid = nd->nodeid;
979 		node->weight = nd->weight;
980 		node->new = nd->new;
981 		node->comm_seq = nd->comm_seq;
982 		node++;
983 
984 		nd->new = 0;
985 	}
986 
987 	*count_out = count;
988 	*nodes_out = nodes;
989 	rv = 0;
990  out:
991 	mutex_unlock(&sp->members_lock);
992 	put_space(sp);
993 	return rv;
994 }
995 
996 int dlm_comm_seq(int nodeid, uint32_t *seq)
997 {
998 	struct dlm_comm *cm = get_comm(nodeid, NULL);
999 	if (!cm)
1000 		return -EEXIST;
1001 	*seq = cm->seq;
1002 	put_comm(cm);
1003 	return 0;
1004 }
1005 
1006 int dlm_nodeid_to_addr(int nodeid, struct sockaddr_storage *addr)
1007 {
1008 	struct dlm_comm *cm = get_comm(nodeid, NULL);
1009 	if (!cm)
1010 		return -EEXIST;
1011 	if (!cm->addr_count)
1012 		return -ENOENT;
1013 	memcpy(addr, cm->addr[0], sizeof(*addr));
1014 	put_comm(cm);
1015 	return 0;
1016 }
1017 
1018 int dlm_addr_to_nodeid(struct sockaddr_storage *addr, int *nodeid)
1019 {
1020 	struct dlm_comm *cm = get_comm(0, addr);
1021 	if (!cm)
1022 		return -EEXIST;
1023 	*nodeid = cm->nodeid;
1024 	put_comm(cm);
1025 	return 0;
1026 }
1027 
1028 int dlm_our_nodeid(void)
1029 {
1030 	return local_comm ? local_comm->nodeid : 0;
1031 }
1032 
1033 /* num 0 is first addr, num 1 is second addr */
1034 int dlm_our_addr(struct sockaddr_storage *addr, int num)
1035 {
1036 	if (!local_comm)
1037 		return -1;
1038 	if (num + 1 > local_comm->addr_count)
1039 		return -1;
1040 	memcpy(addr, local_comm->addr[num], sizeof(*addr));
1041 	return 0;
1042 }
1043 
1044 /* Config file defaults */
1045 #define DEFAULT_TCP_PORT       21064
1046 #define DEFAULT_BUFFER_SIZE     4096
1047 #define DEFAULT_RSBTBL_SIZE     1024
1048 #define DEFAULT_RECOVER_TIMER      5
1049 #define DEFAULT_TOSS_SECS         10
1050 #define DEFAULT_SCAN_SECS          5
1051 #define DEFAULT_LOG_DEBUG          0
1052 #define DEFAULT_PROTOCOL           0
1053 #define DEFAULT_TIMEWARN_CS      500 /* 5 sec = 500 centiseconds */
1054 #define DEFAULT_WAITWARN_US	   0
1055 #define DEFAULT_NEW_RSB_COUNT    128
1056 #define DEFAULT_RECOVER_CALLBACKS  0
1057 #define DEFAULT_CLUSTER_NAME      ""
1058 
1059 struct dlm_config_info dlm_config = {
1060 	.ci_tcp_port = DEFAULT_TCP_PORT,
1061 	.ci_buffer_size = DEFAULT_BUFFER_SIZE,
1062 	.ci_rsbtbl_size = DEFAULT_RSBTBL_SIZE,
1063 	.ci_recover_timer = DEFAULT_RECOVER_TIMER,
1064 	.ci_toss_secs = DEFAULT_TOSS_SECS,
1065 	.ci_scan_secs = DEFAULT_SCAN_SECS,
1066 	.ci_log_debug = DEFAULT_LOG_DEBUG,
1067 	.ci_protocol = DEFAULT_PROTOCOL,
1068 	.ci_timewarn_cs = DEFAULT_TIMEWARN_CS,
1069 	.ci_waitwarn_us = DEFAULT_WAITWARN_US,
1070 	.ci_new_rsb_count = DEFAULT_NEW_RSB_COUNT,
1071 	.ci_recover_callbacks = DEFAULT_RECOVER_CALLBACKS,
1072 	.ci_cluster_name = DEFAULT_CLUSTER_NAME
1073 };
1074 
1075