xref: /linux/fs/dlm/config.c (revision b0148a98ec5151fec82064d95f11eb9efbc628ea)
1 /******************************************************************************
2 *******************************************************************************
3 **
4 **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
5 **  Copyright (C) 2004-2005 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 <net/sock.h>
18 
19 #include "config.h"
20 #include "lowcomms.h"
21 
22 /*
23  * /config/dlm/<cluster>/spaces/<space>/nodes/<node>/nodeid
24  * /config/dlm/<cluster>/spaces/<space>/nodes/<node>/weight
25  * /config/dlm/<cluster>/comms/<comm>/nodeid
26  * /config/dlm/<cluster>/comms/<comm>/local
27  * /config/dlm/<cluster>/comms/<comm>/addr
28  * The <cluster> level is useless, but I haven't figured out how to avoid it.
29  */
30 
31 static struct config_group *space_list;
32 static struct config_group *comm_list;
33 static struct comm *local_comm;
34 
35 struct clusters;
36 struct cluster;
37 struct spaces;
38 struct space;
39 struct comms;
40 struct comm;
41 struct nodes;
42 struct node;
43 
44 static struct config_group *make_cluster(struct config_group *, const char *);
45 static void drop_cluster(struct config_group *, struct config_item *);
46 static void release_cluster(struct config_item *);
47 static struct config_group *make_space(struct config_group *, const char *);
48 static void drop_space(struct config_group *, struct config_item *);
49 static void release_space(struct config_item *);
50 static struct config_item *make_comm(struct config_group *, const char *);
51 static void drop_comm(struct config_group *, struct config_item *);
52 static void release_comm(struct config_item *);
53 static struct config_item *make_node(struct config_group *, const char *);
54 static void drop_node(struct config_group *, struct config_item *);
55 static void release_node(struct config_item *);
56 
57 static ssize_t show_cluster(struct config_item *i, struct configfs_attribute *a,
58 			    char *buf);
59 static ssize_t store_cluster(struct config_item *i,
60 			     struct configfs_attribute *a,
61 			     const char *buf, size_t len);
62 static ssize_t show_comm(struct config_item *i, struct configfs_attribute *a,
63 			 char *buf);
64 static ssize_t store_comm(struct config_item *i, struct configfs_attribute *a,
65 			  const char *buf, size_t len);
66 static ssize_t show_node(struct config_item *i, struct configfs_attribute *a,
67 			 char *buf);
68 static ssize_t store_node(struct config_item *i, struct configfs_attribute *a,
69 			  const char *buf, size_t len);
70 
71 static ssize_t comm_nodeid_read(struct comm *cm, char *buf);
72 static ssize_t comm_nodeid_write(struct comm *cm, const char *buf, size_t len);
73 static ssize_t comm_local_read(struct comm *cm, char *buf);
74 static ssize_t comm_local_write(struct comm *cm, const char *buf, size_t len);
75 static ssize_t comm_addr_write(struct comm *cm, const char *buf, size_t len);
76 static ssize_t node_nodeid_read(struct node *nd, char *buf);
77 static ssize_t node_nodeid_write(struct node *nd, const char *buf, size_t len);
78 static ssize_t node_weight_read(struct node *nd, char *buf);
79 static ssize_t node_weight_write(struct node *nd, const char *buf, size_t len);
80 
81 struct cluster {
82 	struct config_group group;
83 	unsigned int cl_tcp_port;
84 	unsigned int cl_buffer_size;
85 	unsigned int cl_rsbtbl_size;
86 	unsigned int cl_lkbtbl_size;
87 	unsigned int cl_dirtbl_size;
88 	unsigned int cl_recover_timer;
89 	unsigned int cl_toss_secs;
90 	unsigned int cl_scan_secs;
91 	unsigned int cl_log_debug;
92 };
93 
94 enum {
95 	CLUSTER_ATTR_TCP_PORT = 0,
96 	CLUSTER_ATTR_BUFFER_SIZE,
97 	CLUSTER_ATTR_RSBTBL_SIZE,
98 	CLUSTER_ATTR_LKBTBL_SIZE,
99 	CLUSTER_ATTR_DIRTBL_SIZE,
100 	CLUSTER_ATTR_RECOVER_TIMER,
101 	CLUSTER_ATTR_TOSS_SECS,
102 	CLUSTER_ATTR_SCAN_SECS,
103 	CLUSTER_ATTR_LOG_DEBUG,
104 };
105 
106 struct cluster_attribute {
107 	struct configfs_attribute attr;
108 	ssize_t (*show)(struct cluster *, char *);
109 	ssize_t (*store)(struct cluster *, const char *, size_t);
110 };
111 
112 static ssize_t cluster_set(struct cluster *cl, unsigned int *cl_field,
113 			   unsigned int *info_field, int check_zero,
114 			   const char *buf, size_t len)
115 {
116 	unsigned int x;
117 
118 	if (!capable(CAP_SYS_ADMIN))
119 		return -EACCES;
120 
121 	x = simple_strtoul(buf, NULL, 0);
122 
123 	if (check_zero && !x)
124 		return -EINVAL;
125 
126 	*cl_field = x;
127 	*info_field = x;
128 
129 	return len;
130 }
131 
132 #define __CONFIGFS_ATTR(_name,_mode,_read,_write) {                           \
133 	.attr   = { .ca_name = __stringify(_name),                            \
134 		    .ca_mode = _mode,                                         \
135 		    .ca_owner = THIS_MODULE },                                \
136 	.show   = _read,                                                      \
137 	.store  = _write,                                                     \
138 }
139 
140 #define CLUSTER_ATTR(name, check_zero)                                        \
141 static ssize_t name##_write(struct cluster *cl, const char *buf, size_t len)  \
142 {                                                                             \
143 	return cluster_set(cl, &cl->cl_##name, &dlm_config.ci_##name,         \
144 			   check_zero, buf, len);                             \
145 }                                                                             \
146 static ssize_t name##_read(struct cluster *cl, char *buf)                     \
147 {                                                                             \
148 	return snprintf(buf, PAGE_SIZE, "%u\n", cl->cl_##name);               \
149 }                                                                             \
150 static struct cluster_attribute cluster_attr_##name =                         \
151 __CONFIGFS_ATTR(name, 0644, name##_read, name##_write)
152 
153 CLUSTER_ATTR(tcp_port, 1);
154 CLUSTER_ATTR(buffer_size, 1);
155 CLUSTER_ATTR(rsbtbl_size, 1);
156 CLUSTER_ATTR(lkbtbl_size, 1);
157 CLUSTER_ATTR(dirtbl_size, 1);
158 CLUSTER_ATTR(recover_timer, 1);
159 CLUSTER_ATTR(toss_secs, 1);
160 CLUSTER_ATTR(scan_secs, 1);
161 CLUSTER_ATTR(log_debug, 0);
162 
163 static struct configfs_attribute *cluster_attrs[] = {
164 	[CLUSTER_ATTR_TCP_PORT] = &cluster_attr_tcp_port.attr,
165 	[CLUSTER_ATTR_BUFFER_SIZE] = &cluster_attr_buffer_size.attr,
166 	[CLUSTER_ATTR_RSBTBL_SIZE] = &cluster_attr_rsbtbl_size.attr,
167 	[CLUSTER_ATTR_LKBTBL_SIZE] = &cluster_attr_lkbtbl_size.attr,
168 	[CLUSTER_ATTR_DIRTBL_SIZE] = &cluster_attr_dirtbl_size.attr,
169 	[CLUSTER_ATTR_RECOVER_TIMER] = &cluster_attr_recover_timer.attr,
170 	[CLUSTER_ATTR_TOSS_SECS] = &cluster_attr_toss_secs.attr,
171 	[CLUSTER_ATTR_SCAN_SECS] = &cluster_attr_scan_secs.attr,
172 	[CLUSTER_ATTR_LOG_DEBUG] = &cluster_attr_log_debug.attr,
173 	NULL,
174 };
175 
176 enum {
177 	COMM_ATTR_NODEID = 0,
178 	COMM_ATTR_LOCAL,
179 	COMM_ATTR_ADDR,
180 };
181 
182 struct comm_attribute {
183 	struct configfs_attribute attr;
184 	ssize_t (*show)(struct comm *, char *);
185 	ssize_t (*store)(struct comm *, const char *, size_t);
186 };
187 
188 static struct comm_attribute comm_attr_nodeid = {
189 	.attr   = { .ca_owner = THIS_MODULE,
190                     .ca_name = "nodeid",
191                     .ca_mode = S_IRUGO | S_IWUSR },
192 	.show   = comm_nodeid_read,
193 	.store  = comm_nodeid_write,
194 };
195 
196 static struct comm_attribute comm_attr_local = {
197 	.attr   = { .ca_owner = THIS_MODULE,
198                     .ca_name = "local",
199                     .ca_mode = S_IRUGO | S_IWUSR },
200 	.show   = comm_local_read,
201 	.store  = comm_local_write,
202 };
203 
204 static struct comm_attribute comm_attr_addr = {
205 	.attr   = { .ca_owner = THIS_MODULE,
206                     .ca_name = "addr",
207                     .ca_mode = S_IRUGO | S_IWUSR },
208 	.store  = comm_addr_write,
209 };
210 
211 static struct configfs_attribute *comm_attrs[] = {
212 	[COMM_ATTR_NODEID] = &comm_attr_nodeid.attr,
213 	[COMM_ATTR_LOCAL] = &comm_attr_local.attr,
214 	[COMM_ATTR_ADDR] = &comm_attr_addr.attr,
215 	NULL,
216 };
217 
218 enum {
219 	NODE_ATTR_NODEID = 0,
220 	NODE_ATTR_WEIGHT,
221 };
222 
223 struct node_attribute {
224 	struct configfs_attribute attr;
225 	ssize_t (*show)(struct node *, char *);
226 	ssize_t (*store)(struct node *, const char *, size_t);
227 };
228 
229 static struct node_attribute node_attr_nodeid = {
230 	.attr   = { .ca_owner = THIS_MODULE,
231                     .ca_name = "nodeid",
232                     .ca_mode = S_IRUGO | S_IWUSR },
233 	.show   = node_nodeid_read,
234 	.store  = node_nodeid_write,
235 };
236 
237 static struct node_attribute node_attr_weight = {
238 	.attr   = { .ca_owner = THIS_MODULE,
239                     .ca_name = "weight",
240                     .ca_mode = S_IRUGO | S_IWUSR },
241 	.show   = node_weight_read,
242 	.store  = node_weight_write,
243 };
244 
245 static struct configfs_attribute *node_attrs[] = {
246 	[NODE_ATTR_NODEID] = &node_attr_nodeid.attr,
247 	[NODE_ATTR_WEIGHT] = &node_attr_weight.attr,
248 	NULL,
249 };
250 
251 struct clusters {
252 	struct configfs_subsystem subsys;
253 };
254 
255 struct spaces {
256 	struct config_group ss_group;
257 };
258 
259 struct space {
260 	struct config_group group;
261 	struct list_head members;
262 	struct mutex members_lock;
263 	int members_count;
264 };
265 
266 struct comms {
267 	struct config_group cs_group;
268 };
269 
270 struct comm {
271 	struct config_item item;
272 	int nodeid;
273 	int local;
274 	int addr_count;
275 	struct sockaddr_storage *addr[DLM_MAX_ADDR_COUNT];
276 };
277 
278 struct nodes {
279 	struct config_group ns_group;
280 };
281 
282 struct node {
283 	struct config_item item;
284 	struct list_head list; /* space->members */
285 	int nodeid;
286 	int weight;
287 };
288 
289 static struct configfs_group_operations clusters_ops = {
290 	.make_group = make_cluster,
291 	.drop_item = drop_cluster,
292 };
293 
294 static struct configfs_item_operations cluster_ops = {
295 	.release = release_cluster,
296 	.show_attribute = show_cluster,
297 	.store_attribute = store_cluster,
298 };
299 
300 static struct configfs_group_operations spaces_ops = {
301 	.make_group = make_space,
302 	.drop_item = drop_space,
303 };
304 
305 static struct configfs_item_operations space_ops = {
306 	.release = release_space,
307 };
308 
309 static struct configfs_group_operations comms_ops = {
310 	.make_item = make_comm,
311 	.drop_item = drop_comm,
312 };
313 
314 static struct configfs_item_operations comm_ops = {
315 	.release = release_comm,
316 	.show_attribute = show_comm,
317 	.store_attribute = store_comm,
318 };
319 
320 static struct configfs_group_operations nodes_ops = {
321 	.make_item = make_node,
322 	.drop_item = drop_node,
323 };
324 
325 static struct configfs_item_operations node_ops = {
326 	.release = release_node,
327 	.show_attribute = show_node,
328 	.store_attribute = store_node,
329 };
330 
331 static struct config_item_type clusters_type = {
332 	.ct_group_ops = &clusters_ops,
333 	.ct_owner = THIS_MODULE,
334 };
335 
336 static struct config_item_type cluster_type = {
337 	.ct_item_ops = &cluster_ops,
338 	.ct_attrs = cluster_attrs,
339 	.ct_owner = THIS_MODULE,
340 };
341 
342 static struct config_item_type spaces_type = {
343 	.ct_group_ops = &spaces_ops,
344 	.ct_owner = THIS_MODULE,
345 };
346 
347 static struct config_item_type space_type = {
348 	.ct_item_ops = &space_ops,
349 	.ct_owner = THIS_MODULE,
350 };
351 
352 static struct config_item_type comms_type = {
353 	.ct_group_ops = &comms_ops,
354 	.ct_owner = THIS_MODULE,
355 };
356 
357 static struct config_item_type comm_type = {
358 	.ct_item_ops = &comm_ops,
359 	.ct_attrs = comm_attrs,
360 	.ct_owner = THIS_MODULE,
361 };
362 
363 static struct config_item_type nodes_type = {
364 	.ct_group_ops = &nodes_ops,
365 	.ct_owner = THIS_MODULE,
366 };
367 
368 static struct config_item_type node_type = {
369 	.ct_item_ops = &node_ops,
370 	.ct_attrs = node_attrs,
371 	.ct_owner = THIS_MODULE,
372 };
373 
374 static struct cluster *to_cluster(struct config_item *i)
375 {
376 	return i ? container_of(to_config_group(i), struct cluster, group):NULL;
377 }
378 
379 static struct space *to_space(struct config_item *i)
380 {
381 	return i ? container_of(to_config_group(i), struct space, group) : NULL;
382 }
383 
384 static struct comm *to_comm(struct config_item *i)
385 {
386 	return i ? container_of(i, struct comm, item) : NULL;
387 }
388 
389 static struct node *to_node(struct config_item *i)
390 {
391 	return i ? container_of(i, struct node, item) : NULL;
392 }
393 
394 static struct config_group *make_cluster(struct config_group *g,
395 					 const char *name)
396 {
397 	struct cluster *cl = NULL;
398 	struct spaces *sps = NULL;
399 	struct comms *cms = NULL;
400 	void *gps = NULL;
401 
402 	cl = kzalloc(sizeof(struct cluster), GFP_KERNEL);
403 	gps = kcalloc(3, sizeof(struct config_group *), GFP_KERNEL);
404 	sps = kzalloc(sizeof(struct spaces), GFP_KERNEL);
405 	cms = kzalloc(sizeof(struct comms), GFP_KERNEL);
406 
407 	if (!cl || !gps || !sps || !cms)
408 		goto fail;
409 
410 	config_group_init_type_name(&cl->group, name, &cluster_type);
411 	config_group_init_type_name(&sps->ss_group, "spaces", &spaces_type);
412 	config_group_init_type_name(&cms->cs_group, "comms", &comms_type);
413 
414 	cl->group.default_groups = gps;
415 	cl->group.default_groups[0] = &sps->ss_group;
416 	cl->group.default_groups[1] = &cms->cs_group;
417 	cl->group.default_groups[2] = NULL;
418 
419 	cl->cl_tcp_port = dlm_config.ci_tcp_port;
420 	cl->cl_buffer_size = dlm_config.ci_buffer_size;
421 	cl->cl_rsbtbl_size = dlm_config.ci_rsbtbl_size;
422 	cl->cl_lkbtbl_size = dlm_config.ci_lkbtbl_size;
423 	cl->cl_dirtbl_size = dlm_config.ci_dirtbl_size;
424 	cl->cl_recover_timer = dlm_config.ci_recover_timer;
425 	cl->cl_toss_secs = dlm_config.ci_toss_secs;
426 	cl->cl_scan_secs = dlm_config.ci_scan_secs;
427 	cl->cl_log_debug = dlm_config.ci_log_debug;
428 
429 	space_list = &sps->ss_group;
430 	comm_list = &cms->cs_group;
431 	return &cl->group;
432 
433  fail:
434 	kfree(cl);
435 	kfree(gps);
436 	kfree(sps);
437 	kfree(cms);
438 	return NULL;
439 }
440 
441 static void drop_cluster(struct config_group *g, struct config_item *i)
442 {
443 	struct cluster *cl = to_cluster(i);
444 	struct config_item *tmp;
445 	int j;
446 
447 	for (j = 0; cl->group.default_groups[j]; j++) {
448 		tmp = &cl->group.default_groups[j]->cg_item;
449 		cl->group.default_groups[j] = NULL;
450 		config_item_put(tmp);
451 	}
452 
453 	space_list = NULL;
454 	comm_list = NULL;
455 
456 	config_item_put(i);
457 }
458 
459 static void release_cluster(struct config_item *i)
460 {
461 	struct cluster *cl = to_cluster(i);
462 	kfree(cl->group.default_groups);
463 	kfree(cl);
464 }
465 
466 static struct config_group *make_space(struct config_group *g, const char *name)
467 {
468 	struct space *sp = NULL;
469 	struct nodes *nds = NULL;
470 	void *gps = NULL;
471 
472 	sp = kzalloc(sizeof(struct space), GFP_KERNEL);
473 	gps = kcalloc(2, sizeof(struct config_group *), GFP_KERNEL);
474 	nds = kzalloc(sizeof(struct nodes), GFP_KERNEL);
475 
476 	if (!sp || !gps || !nds)
477 		goto fail;
478 
479 	config_group_init_type_name(&sp->group, name, &space_type);
480 	config_group_init_type_name(&nds->ns_group, "nodes", &nodes_type);
481 
482 	sp->group.default_groups = gps;
483 	sp->group.default_groups[0] = &nds->ns_group;
484 	sp->group.default_groups[1] = NULL;
485 
486 	INIT_LIST_HEAD(&sp->members);
487 	mutex_init(&sp->members_lock);
488 	sp->members_count = 0;
489 	return &sp->group;
490 
491  fail:
492 	kfree(sp);
493 	kfree(gps);
494 	kfree(nds);
495 	return NULL;
496 }
497 
498 static void drop_space(struct config_group *g, struct config_item *i)
499 {
500 	struct space *sp = to_space(i);
501 	struct config_item *tmp;
502 	int j;
503 
504 	/* assert list_empty(&sp->members) */
505 
506 	for (j = 0; sp->group.default_groups[j]; j++) {
507 		tmp = &sp->group.default_groups[j]->cg_item;
508 		sp->group.default_groups[j] = NULL;
509 		config_item_put(tmp);
510 	}
511 
512 	config_item_put(i);
513 }
514 
515 static void release_space(struct config_item *i)
516 {
517 	struct space *sp = to_space(i);
518 	kfree(sp->group.default_groups);
519 	kfree(sp);
520 }
521 
522 static struct config_item *make_comm(struct config_group *g, const char *name)
523 {
524 	struct comm *cm;
525 
526 	cm = kzalloc(sizeof(struct comm), GFP_KERNEL);
527 	if (!cm)
528 		return NULL;
529 
530 	config_item_init_type_name(&cm->item, name, &comm_type);
531 	cm->nodeid = -1;
532 	cm->local = 0;
533 	cm->addr_count = 0;
534 	return &cm->item;
535 }
536 
537 static void drop_comm(struct config_group *g, struct config_item *i)
538 {
539 	struct comm *cm = to_comm(i);
540 	if (local_comm == cm)
541 		local_comm = NULL;
542 	dlm_lowcomms_close(cm->nodeid);
543 	while (cm->addr_count--)
544 		kfree(cm->addr[cm->addr_count]);
545 	config_item_put(i);
546 }
547 
548 static void release_comm(struct config_item *i)
549 {
550 	struct comm *cm = to_comm(i);
551 	kfree(cm);
552 }
553 
554 static struct config_item *make_node(struct config_group *g, const char *name)
555 {
556 	struct space *sp = to_space(g->cg_item.ci_parent);
557 	struct node *nd;
558 
559 	nd = kzalloc(sizeof(struct node), GFP_KERNEL);
560 	if (!nd)
561 		return NULL;
562 
563 	config_item_init_type_name(&nd->item, name, &node_type);
564 	nd->nodeid = -1;
565 	nd->weight = 1;  /* default weight of 1 if none is set */
566 
567 	mutex_lock(&sp->members_lock);
568 	list_add(&nd->list, &sp->members);
569 	sp->members_count++;
570 	mutex_unlock(&sp->members_lock);
571 
572 	return &nd->item;
573 }
574 
575 static void drop_node(struct config_group *g, struct config_item *i)
576 {
577 	struct space *sp = to_space(g->cg_item.ci_parent);
578 	struct node *nd = to_node(i);
579 
580 	mutex_lock(&sp->members_lock);
581 	list_del(&nd->list);
582 	sp->members_count--;
583 	mutex_unlock(&sp->members_lock);
584 
585 	config_item_put(i);
586 }
587 
588 static void release_node(struct config_item *i)
589 {
590 	struct node *nd = to_node(i);
591 	kfree(nd);
592 }
593 
594 static struct clusters clusters_root = {
595 	.subsys = {
596 		.su_group = {
597 			.cg_item = {
598 				.ci_namebuf = "dlm",
599 				.ci_type = &clusters_type,
600 			},
601 		},
602 	},
603 };
604 
605 int dlm_config_init(void)
606 {
607 	config_group_init(&clusters_root.subsys.su_group);
608 	init_MUTEX(&clusters_root.subsys.su_sem);
609 	return configfs_register_subsystem(&clusters_root.subsys);
610 }
611 
612 void dlm_config_exit(void)
613 {
614 	configfs_unregister_subsystem(&clusters_root.subsys);
615 }
616 
617 /*
618  * Functions for user space to read/write attributes
619  */
620 
621 static ssize_t show_cluster(struct config_item *i, struct configfs_attribute *a,
622 			    char *buf)
623 {
624 	struct cluster *cl = to_cluster(i);
625 	struct cluster_attribute *cla =
626 			container_of(a, struct cluster_attribute, attr);
627 	return cla->show ? cla->show(cl, buf) : 0;
628 }
629 
630 static ssize_t store_cluster(struct config_item *i,
631 			     struct configfs_attribute *a,
632 			     const char *buf, size_t len)
633 {
634 	struct cluster *cl = to_cluster(i);
635 	struct cluster_attribute *cla =
636 		container_of(a, struct cluster_attribute, attr);
637 	return cla->store ? cla->store(cl, buf, len) : -EINVAL;
638 }
639 
640 static ssize_t show_comm(struct config_item *i, struct configfs_attribute *a,
641 			 char *buf)
642 {
643 	struct comm *cm = to_comm(i);
644 	struct comm_attribute *cma =
645 			container_of(a, struct comm_attribute, attr);
646 	return cma->show ? cma->show(cm, buf) : 0;
647 }
648 
649 static ssize_t store_comm(struct config_item *i, struct configfs_attribute *a,
650 			  const char *buf, size_t len)
651 {
652 	struct comm *cm = to_comm(i);
653 	struct comm_attribute *cma =
654 		container_of(a, struct comm_attribute, attr);
655 	return cma->store ? cma->store(cm, buf, len) : -EINVAL;
656 }
657 
658 static ssize_t comm_nodeid_read(struct comm *cm, char *buf)
659 {
660 	return sprintf(buf, "%d\n", cm->nodeid);
661 }
662 
663 static ssize_t comm_nodeid_write(struct comm *cm, const char *buf, size_t len)
664 {
665 	cm->nodeid = simple_strtol(buf, NULL, 0);
666 	return len;
667 }
668 
669 static ssize_t comm_local_read(struct comm *cm, char *buf)
670 {
671 	return sprintf(buf, "%d\n", cm->local);
672 }
673 
674 static ssize_t comm_local_write(struct comm *cm, const char *buf, size_t len)
675 {
676 	cm->local= simple_strtol(buf, NULL, 0);
677 	if (cm->local && !local_comm)
678 		local_comm = cm;
679 	return len;
680 }
681 
682 static ssize_t comm_addr_write(struct comm *cm, const char *buf, size_t len)
683 {
684 	struct sockaddr_storage *addr;
685 
686 	if (len != sizeof(struct sockaddr_storage))
687 		return -EINVAL;
688 
689 	if (cm->addr_count >= DLM_MAX_ADDR_COUNT)
690 		return -ENOSPC;
691 
692 	addr = kzalloc(sizeof(*addr), GFP_KERNEL);
693 	if (!addr)
694 		return -ENOMEM;
695 
696 	memcpy(addr, buf, len);
697 	cm->addr[cm->addr_count++] = addr;
698 	return len;
699 }
700 
701 static ssize_t show_node(struct config_item *i, struct configfs_attribute *a,
702 			 char *buf)
703 {
704 	struct node *nd = to_node(i);
705 	struct node_attribute *nda =
706 			container_of(a, struct node_attribute, attr);
707 	return nda->show ? nda->show(nd, buf) : 0;
708 }
709 
710 static ssize_t store_node(struct config_item *i, struct configfs_attribute *a,
711 			  const char *buf, size_t len)
712 {
713 	struct node *nd = to_node(i);
714 	struct node_attribute *nda =
715 		container_of(a, struct node_attribute, attr);
716 	return nda->store ? nda->store(nd, buf, len) : -EINVAL;
717 }
718 
719 static ssize_t node_nodeid_read(struct node *nd, char *buf)
720 {
721 	return sprintf(buf, "%d\n", nd->nodeid);
722 }
723 
724 static ssize_t node_nodeid_write(struct node *nd, const char *buf, size_t len)
725 {
726 	nd->nodeid = simple_strtol(buf, NULL, 0);
727 	return len;
728 }
729 
730 static ssize_t node_weight_read(struct node *nd, char *buf)
731 {
732 	return sprintf(buf, "%d\n", nd->weight);
733 }
734 
735 static ssize_t node_weight_write(struct node *nd, const char *buf, size_t len)
736 {
737 	nd->weight = simple_strtol(buf, NULL, 0);
738 	return len;
739 }
740 
741 /*
742  * Functions for the dlm to get the info that's been configured
743  */
744 
745 static struct space *get_space(char *name)
746 {
747 	if (!space_list)
748 		return NULL;
749 	return to_space(config_group_find_obj(space_list, name));
750 }
751 
752 static void put_space(struct space *sp)
753 {
754 	config_item_put(&sp->group.cg_item);
755 }
756 
757 static struct comm *get_comm(int nodeid, struct sockaddr_storage *addr)
758 {
759 	struct config_item *i;
760 	struct comm *cm = NULL;
761 	int found = 0;
762 
763 	if (!comm_list)
764 		return NULL;
765 
766 	down(&clusters_root.subsys.su_sem);
767 
768 	list_for_each_entry(i, &comm_list->cg_children, ci_entry) {
769 		cm = to_comm(i);
770 
771 		if (nodeid) {
772 			if (cm->nodeid != nodeid)
773 				continue;
774 			found = 1;
775 			break;
776 		} else {
777 			if (!cm->addr_count ||
778 			    memcmp(cm->addr[0], addr, sizeof(*addr)))
779 				continue;
780 			found = 1;
781 			break;
782 		}
783 	}
784 	up(&clusters_root.subsys.su_sem);
785 
786 	if (found)
787 		config_item_get(i);
788 	else
789 		cm = NULL;
790 	return cm;
791 }
792 
793 static void put_comm(struct comm *cm)
794 {
795 	config_item_put(&cm->item);
796 }
797 
798 /* caller must free mem */
799 int dlm_nodeid_list(char *lsname, int **ids_out)
800 {
801 	struct space *sp;
802 	struct node *nd;
803 	int i = 0, rv = 0;
804 	int *ids;
805 
806 	sp = get_space(lsname);
807 	if (!sp)
808 		return -EEXIST;
809 
810 	mutex_lock(&sp->members_lock);
811 	if (!sp->members_count) {
812 		rv = 0;
813 		goto out;
814 	}
815 
816 	ids = kcalloc(sp->members_count, sizeof(int), GFP_KERNEL);
817 	if (!ids) {
818 		rv = -ENOMEM;
819 		goto out;
820 	}
821 
822 	rv = sp->members_count;
823 	list_for_each_entry(nd, &sp->members, list)
824 		ids[i++] = nd->nodeid;
825 
826 	if (rv != i)
827 		printk("bad nodeid count %d %d\n", rv, i);
828 
829 	*ids_out = ids;
830  out:
831 	mutex_unlock(&sp->members_lock);
832 	put_space(sp);
833 	return rv;
834 }
835 
836 int dlm_node_weight(char *lsname, int nodeid)
837 {
838 	struct space *sp;
839 	struct node *nd;
840 	int w = -EEXIST;
841 
842 	sp = get_space(lsname);
843 	if (!sp)
844 		goto out;
845 
846 	mutex_lock(&sp->members_lock);
847 	list_for_each_entry(nd, &sp->members, list) {
848 		if (nd->nodeid != nodeid)
849 			continue;
850 		w = nd->weight;
851 		break;
852 	}
853 	mutex_unlock(&sp->members_lock);
854 	put_space(sp);
855  out:
856 	return w;
857 }
858 
859 int dlm_nodeid_to_addr(int nodeid, struct sockaddr_storage *addr)
860 {
861 	struct comm *cm = get_comm(nodeid, NULL);
862 	if (!cm)
863 		return -EEXIST;
864 	if (!cm->addr_count)
865 		return -ENOENT;
866 	memcpy(addr, cm->addr[0], sizeof(*addr));
867 	put_comm(cm);
868 	return 0;
869 }
870 
871 int dlm_addr_to_nodeid(struct sockaddr_storage *addr, int *nodeid)
872 {
873 	struct comm *cm = get_comm(0, addr);
874 	if (!cm)
875 		return -EEXIST;
876 	*nodeid = cm->nodeid;
877 	put_comm(cm);
878 	return 0;
879 }
880 
881 int dlm_our_nodeid(void)
882 {
883 	return local_comm ? local_comm->nodeid : 0;
884 }
885 
886 /* num 0 is first addr, num 1 is second addr */
887 int dlm_our_addr(struct sockaddr_storage *addr, int num)
888 {
889 	if (!local_comm)
890 		return -1;
891 	if (num + 1 > local_comm->addr_count)
892 		return -1;
893 	memcpy(addr, local_comm->addr[num], sizeof(*addr));
894 	return 0;
895 }
896 
897 /* Config file defaults */
898 #define DEFAULT_TCP_PORT       21064
899 #define DEFAULT_BUFFER_SIZE     4096
900 #define DEFAULT_RSBTBL_SIZE      256
901 #define DEFAULT_LKBTBL_SIZE     1024
902 #define DEFAULT_DIRTBL_SIZE      512
903 #define DEFAULT_RECOVER_TIMER      5
904 #define DEFAULT_TOSS_SECS         10
905 #define DEFAULT_SCAN_SECS          5
906 #define DEFAULT_LOG_DEBUG          0
907 
908 struct dlm_config_info dlm_config = {
909 	.ci_tcp_port = DEFAULT_TCP_PORT,
910 	.ci_buffer_size = DEFAULT_BUFFER_SIZE,
911 	.ci_rsbtbl_size = DEFAULT_RSBTBL_SIZE,
912 	.ci_lkbtbl_size = DEFAULT_LKBTBL_SIZE,
913 	.ci_dirtbl_size = DEFAULT_DIRTBL_SIZE,
914 	.ci_recover_timer = DEFAULT_RECOVER_TIMER,
915 	.ci_toss_secs = DEFAULT_TOSS_SECS,
916 	.ci_scan_secs = DEFAULT_SCAN_SECS,
917 	.ci_log_debug = DEFAULT_LOG_DEBUG
918 };
919 
920