xref: /openbmc/linux/fs/dlm/config.c (revision d2999e1b)
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 	strlcpy(dlm_config.ci_cluster_name, buf,
142 				sizeof(dlm_config.ci_cluster_name));
143 	strlcpy(cl->cl_cluster_name, buf, sizeof(cl->cl_cluster_name));
144 	return len;
145 }
146 
147 static struct cluster_attribute cluster_attr_cluster_name = {
148 	.attr   = { .ca_owner = THIS_MODULE,
149                     .ca_name = "cluster_name",
150                     .ca_mode = S_IRUGO | S_IWUSR },
151 	.show   = cluster_cluster_name_read,
152 	.store  = cluster_cluster_name_write,
153 };
154 
155 static ssize_t cluster_set(struct dlm_cluster *cl, unsigned int *cl_field,
156 			   int *info_field, int check_zero,
157 			   const char *buf, size_t len)
158 {
159 	unsigned int x;
160 	int rc;
161 
162 	if (!capable(CAP_SYS_ADMIN))
163 		return -EPERM;
164 	rc = kstrtouint(buf, 0, &x);
165 	if (rc)
166 		return rc;
167 
168 	if (check_zero && !x)
169 		return -EINVAL;
170 
171 	*cl_field = x;
172 	*info_field = x;
173 
174 	return len;
175 }
176 
177 #define CLUSTER_ATTR(name, check_zero)                                        \
178 static ssize_t name##_write(struct dlm_cluster *cl, const char *buf, size_t len) \
179 {                                                                             \
180 	return cluster_set(cl, &cl->cl_##name, &dlm_config.ci_##name,         \
181 			   check_zero, buf, len);                             \
182 }                                                                             \
183 static ssize_t name##_read(struct dlm_cluster *cl, char *buf)                 \
184 {                                                                             \
185 	return snprintf(buf, PAGE_SIZE, "%u\n", cl->cl_##name);               \
186 }                                                                             \
187 static struct cluster_attribute cluster_attr_##name =                         \
188 __CONFIGFS_ATTR(name, 0644, name##_read, name##_write)
189 
190 CLUSTER_ATTR(tcp_port, 1);
191 CLUSTER_ATTR(buffer_size, 1);
192 CLUSTER_ATTR(rsbtbl_size, 1);
193 CLUSTER_ATTR(recover_timer, 1);
194 CLUSTER_ATTR(toss_secs, 1);
195 CLUSTER_ATTR(scan_secs, 1);
196 CLUSTER_ATTR(log_debug, 0);
197 CLUSTER_ATTR(protocol, 0);
198 CLUSTER_ATTR(timewarn_cs, 1);
199 CLUSTER_ATTR(waitwarn_us, 0);
200 CLUSTER_ATTR(new_rsb_count, 0);
201 CLUSTER_ATTR(recover_callbacks, 0);
202 
203 static struct configfs_attribute *cluster_attrs[] = {
204 	[CLUSTER_ATTR_TCP_PORT] = &cluster_attr_tcp_port.attr,
205 	[CLUSTER_ATTR_BUFFER_SIZE] = &cluster_attr_buffer_size.attr,
206 	[CLUSTER_ATTR_RSBTBL_SIZE] = &cluster_attr_rsbtbl_size.attr,
207 	[CLUSTER_ATTR_RECOVER_TIMER] = &cluster_attr_recover_timer.attr,
208 	[CLUSTER_ATTR_TOSS_SECS] = &cluster_attr_toss_secs.attr,
209 	[CLUSTER_ATTR_SCAN_SECS] = &cluster_attr_scan_secs.attr,
210 	[CLUSTER_ATTR_LOG_DEBUG] = &cluster_attr_log_debug.attr,
211 	[CLUSTER_ATTR_PROTOCOL] = &cluster_attr_protocol.attr,
212 	[CLUSTER_ATTR_TIMEWARN_CS] = &cluster_attr_timewarn_cs.attr,
213 	[CLUSTER_ATTR_WAITWARN_US] = &cluster_attr_waitwarn_us.attr,
214 	[CLUSTER_ATTR_NEW_RSB_COUNT] = &cluster_attr_new_rsb_count.attr,
215 	[CLUSTER_ATTR_RECOVER_CALLBACKS] = &cluster_attr_recover_callbacks.attr,
216 	[CLUSTER_ATTR_CLUSTER_NAME] = &cluster_attr_cluster_name.attr,
217 	NULL,
218 };
219 
220 enum {
221 	COMM_ATTR_NODEID = 0,
222 	COMM_ATTR_LOCAL,
223 	COMM_ATTR_ADDR,
224 	COMM_ATTR_ADDR_LIST,
225 };
226 
227 struct comm_attribute {
228 	struct configfs_attribute attr;
229 	ssize_t (*show)(struct dlm_comm *, char *);
230 	ssize_t (*store)(struct dlm_comm *, const char *, size_t);
231 };
232 
233 static struct comm_attribute comm_attr_nodeid = {
234 	.attr   = { .ca_owner = THIS_MODULE,
235                     .ca_name = "nodeid",
236                     .ca_mode = S_IRUGO | S_IWUSR },
237 	.show   = comm_nodeid_read,
238 	.store  = comm_nodeid_write,
239 };
240 
241 static struct comm_attribute comm_attr_local = {
242 	.attr   = { .ca_owner = THIS_MODULE,
243                     .ca_name = "local",
244                     .ca_mode = S_IRUGO | S_IWUSR },
245 	.show   = comm_local_read,
246 	.store  = comm_local_write,
247 };
248 
249 static struct comm_attribute comm_attr_addr = {
250 	.attr   = { .ca_owner = THIS_MODULE,
251                     .ca_name = "addr",
252                     .ca_mode = S_IWUSR },
253 	.store  = comm_addr_write,
254 };
255 
256 static struct comm_attribute comm_attr_addr_list = {
257 	.attr   = { .ca_owner = THIS_MODULE,
258                     .ca_name = "addr_list",
259                     .ca_mode = S_IRUGO },
260 	.show   = comm_addr_list_read,
261 };
262 
263 static struct configfs_attribute *comm_attrs[] = {
264 	[COMM_ATTR_NODEID] = &comm_attr_nodeid.attr,
265 	[COMM_ATTR_LOCAL] = &comm_attr_local.attr,
266 	[COMM_ATTR_ADDR] = &comm_attr_addr.attr,
267 	[COMM_ATTR_ADDR_LIST] = &comm_attr_addr_list.attr,
268 	NULL,
269 };
270 
271 enum {
272 	NODE_ATTR_NODEID = 0,
273 	NODE_ATTR_WEIGHT,
274 };
275 
276 struct node_attribute {
277 	struct configfs_attribute attr;
278 	ssize_t (*show)(struct dlm_node *, char *);
279 	ssize_t (*store)(struct dlm_node *, const char *, size_t);
280 };
281 
282 static struct node_attribute node_attr_nodeid = {
283 	.attr   = { .ca_owner = THIS_MODULE,
284                     .ca_name = "nodeid",
285                     .ca_mode = S_IRUGO | S_IWUSR },
286 	.show   = node_nodeid_read,
287 	.store  = node_nodeid_write,
288 };
289 
290 static struct node_attribute node_attr_weight = {
291 	.attr   = { .ca_owner = THIS_MODULE,
292                     .ca_name = "weight",
293                     .ca_mode = S_IRUGO | S_IWUSR },
294 	.show   = node_weight_read,
295 	.store  = node_weight_write,
296 };
297 
298 static struct configfs_attribute *node_attrs[] = {
299 	[NODE_ATTR_NODEID] = &node_attr_nodeid.attr,
300 	[NODE_ATTR_WEIGHT] = &node_attr_weight.attr,
301 	NULL,
302 };
303 
304 struct dlm_clusters {
305 	struct configfs_subsystem subsys;
306 };
307 
308 struct dlm_spaces {
309 	struct config_group ss_group;
310 };
311 
312 struct dlm_space {
313 	struct config_group group;
314 	struct list_head members;
315 	struct mutex members_lock;
316 	int members_count;
317 };
318 
319 struct dlm_comms {
320 	struct config_group cs_group;
321 };
322 
323 struct dlm_comm {
324 	struct config_item item;
325 	int seq;
326 	int nodeid;
327 	int local;
328 	int addr_count;
329 	struct sockaddr_storage *addr[DLM_MAX_ADDR_COUNT];
330 };
331 
332 struct dlm_nodes {
333 	struct config_group ns_group;
334 };
335 
336 struct dlm_node {
337 	struct config_item item;
338 	struct list_head list; /* space->members */
339 	int nodeid;
340 	int weight;
341 	int new;
342 	int comm_seq; /* copy of cm->seq when nd->nodeid is set */
343 };
344 
345 static struct configfs_group_operations clusters_ops = {
346 	.make_group = make_cluster,
347 	.drop_item = drop_cluster,
348 };
349 
350 static struct configfs_item_operations cluster_ops = {
351 	.release = release_cluster,
352 	.show_attribute = show_cluster,
353 	.store_attribute = store_cluster,
354 };
355 
356 static struct configfs_group_operations spaces_ops = {
357 	.make_group = make_space,
358 	.drop_item = drop_space,
359 };
360 
361 static struct configfs_item_operations space_ops = {
362 	.release = release_space,
363 };
364 
365 static struct configfs_group_operations comms_ops = {
366 	.make_item = make_comm,
367 	.drop_item = drop_comm,
368 };
369 
370 static struct configfs_item_operations comm_ops = {
371 	.release = release_comm,
372 	.show_attribute = show_comm,
373 	.store_attribute = store_comm,
374 };
375 
376 static struct configfs_group_operations nodes_ops = {
377 	.make_item = make_node,
378 	.drop_item = drop_node,
379 };
380 
381 static struct configfs_item_operations node_ops = {
382 	.release = release_node,
383 	.show_attribute = show_node,
384 	.store_attribute = store_node,
385 };
386 
387 static struct config_item_type clusters_type = {
388 	.ct_group_ops = &clusters_ops,
389 	.ct_owner = THIS_MODULE,
390 };
391 
392 static struct config_item_type cluster_type = {
393 	.ct_item_ops = &cluster_ops,
394 	.ct_attrs = cluster_attrs,
395 	.ct_owner = THIS_MODULE,
396 };
397 
398 static struct config_item_type spaces_type = {
399 	.ct_group_ops = &spaces_ops,
400 	.ct_owner = THIS_MODULE,
401 };
402 
403 static struct config_item_type space_type = {
404 	.ct_item_ops = &space_ops,
405 	.ct_owner = THIS_MODULE,
406 };
407 
408 static struct config_item_type comms_type = {
409 	.ct_group_ops = &comms_ops,
410 	.ct_owner = THIS_MODULE,
411 };
412 
413 static struct config_item_type comm_type = {
414 	.ct_item_ops = &comm_ops,
415 	.ct_attrs = comm_attrs,
416 	.ct_owner = THIS_MODULE,
417 };
418 
419 static struct config_item_type nodes_type = {
420 	.ct_group_ops = &nodes_ops,
421 	.ct_owner = THIS_MODULE,
422 };
423 
424 static struct config_item_type node_type = {
425 	.ct_item_ops = &node_ops,
426 	.ct_attrs = node_attrs,
427 	.ct_owner = THIS_MODULE,
428 };
429 
430 static struct dlm_cluster *config_item_to_cluster(struct config_item *i)
431 {
432 	return i ? container_of(to_config_group(i), struct dlm_cluster, group) :
433 		   NULL;
434 }
435 
436 static struct dlm_space *config_item_to_space(struct config_item *i)
437 {
438 	return i ? container_of(to_config_group(i), struct dlm_space, group) :
439 		   NULL;
440 }
441 
442 static struct dlm_comm *config_item_to_comm(struct config_item *i)
443 {
444 	return i ? container_of(i, struct dlm_comm, item) : NULL;
445 }
446 
447 static struct dlm_node *config_item_to_node(struct config_item *i)
448 {
449 	return i ? container_of(i, struct dlm_node, item) : NULL;
450 }
451 
452 static struct config_group *make_cluster(struct config_group *g,
453 					 const char *name)
454 {
455 	struct dlm_cluster *cl = NULL;
456 	struct dlm_spaces *sps = NULL;
457 	struct dlm_comms *cms = NULL;
458 	void *gps = NULL;
459 
460 	cl = kzalloc(sizeof(struct dlm_cluster), GFP_NOFS);
461 	gps = kcalloc(3, sizeof(struct config_group *), GFP_NOFS);
462 	sps = kzalloc(sizeof(struct dlm_spaces), GFP_NOFS);
463 	cms = kzalloc(sizeof(struct dlm_comms), GFP_NOFS);
464 
465 	if (!cl || !gps || !sps || !cms)
466 		goto fail;
467 
468 	config_group_init_type_name(&cl->group, name, &cluster_type);
469 	config_group_init_type_name(&sps->ss_group, "spaces", &spaces_type);
470 	config_group_init_type_name(&cms->cs_group, "comms", &comms_type);
471 
472 	cl->group.default_groups = gps;
473 	cl->group.default_groups[0] = &sps->ss_group;
474 	cl->group.default_groups[1] = &cms->cs_group;
475 	cl->group.default_groups[2] = NULL;
476 
477 	cl->cl_tcp_port = dlm_config.ci_tcp_port;
478 	cl->cl_buffer_size = dlm_config.ci_buffer_size;
479 	cl->cl_rsbtbl_size = dlm_config.ci_rsbtbl_size;
480 	cl->cl_recover_timer = dlm_config.ci_recover_timer;
481 	cl->cl_toss_secs = dlm_config.ci_toss_secs;
482 	cl->cl_scan_secs = dlm_config.ci_scan_secs;
483 	cl->cl_log_debug = dlm_config.ci_log_debug;
484 	cl->cl_protocol = dlm_config.ci_protocol;
485 	cl->cl_timewarn_cs = dlm_config.ci_timewarn_cs;
486 	cl->cl_waitwarn_us = dlm_config.ci_waitwarn_us;
487 	cl->cl_new_rsb_count = dlm_config.ci_new_rsb_count;
488 	cl->cl_recover_callbacks = dlm_config.ci_recover_callbacks;
489 	memcpy(cl->cl_cluster_name, dlm_config.ci_cluster_name,
490 	       DLM_LOCKSPACE_LEN);
491 
492 	space_list = &sps->ss_group;
493 	comm_list = &cms->cs_group;
494 	return &cl->group;
495 
496  fail:
497 	kfree(cl);
498 	kfree(gps);
499 	kfree(sps);
500 	kfree(cms);
501 	return ERR_PTR(-ENOMEM);
502 }
503 
504 static void drop_cluster(struct config_group *g, struct config_item *i)
505 {
506 	struct dlm_cluster *cl = config_item_to_cluster(i);
507 	struct config_item *tmp;
508 	int j;
509 
510 	for (j = 0; cl->group.default_groups[j]; j++) {
511 		tmp = &cl->group.default_groups[j]->cg_item;
512 		cl->group.default_groups[j] = NULL;
513 		config_item_put(tmp);
514 	}
515 
516 	space_list = NULL;
517 	comm_list = NULL;
518 
519 	config_item_put(i);
520 }
521 
522 static void release_cluster(struct config_item *i)
523 {
524 	struct dlm_cluster *cl = config_item_to_cluster(i);
525 	kfree(cl->group.default_groups);
526 	kfree(cl);
527 }
528 
529 static struct config_group *make_space(struct config_group *g, const char *name)
530 {
531 	struct dlm_space *sp = NULL;
532 	struct dlm_nodes *nds = NULL;
533 	void *gps = NULL;
534 
535 	sp = kzalloc(sizeof(struct dlm_space), GFP_NOFS);
536 	gps = kcalloc(2, sizeof(struct config_group *), GFP_NOFS);
537 	nds = kzalloc(sizeof(struct dlm_nodes), GFP_NOFS);
538 
539 	if (!sp || !gps || !nds)
540 		goto fail;
541 
542 	config_group_init_type_name(&sp->group, name, &space_type);
543 	config_group_init_type_name(&nds->ns_group, "nodes", &nodes_type);
544 
545 	sp->group.default_groups = gps;
546 	sp->group.default_groups[0] = &nds->ns_group;
547 	sp->group.default_groups[1] = NULL;
548 
549 	INIT_LIST_HEAD(&sp->members);
550 	mutex_init(&sp->members_lock);
551 	sp->members_count = 0;
552 	return &sp->group;
553 
554  fail:
555 	kfree(sp);
556 	kfree(gps);
557 	kfree(nds);
558 	return ERR_PTR(-ENOMEM);
559 }
560 
561 static void drop_space(struct config_group *g, struct config_item *i)
562 {
563 	struct dlm_space *sp = config_item_to_space(i);
564 	struct config_item *tmp;
565 	int j;
566 
567 	/* assert list_empty(&sp->members) */
568 
569 	for (j = 0; sp->group.default_groups[j]; j++) {
570 		tmp = &sp->group.default_groups[j]->cg_item;
571 		sp->group.default_groups[j] = NULL;
572 		config_item_put(tmp);
573 	}
574 
575 	config_item_put(i);
576 }
577 
578 static void release_space(struct config_item *i)
579 {
580 	struct dlm_space *sp = config_item_to_space(i);
581 	kfree(sp->group.default_groups);
582 	kfree(sp);
583 }
584 
585 static struct config_item *make_comm(struct config_group *g, const char *name)
586 {
587 	struct dlm_comm *cm;
588 
589 	cm = kzalloc(sizeof(struct dlm_comm), GFP_NOFS);
590 	if (!cm)
591 		return ERR_PTR(-ENOMEM);
592 
593 	config_item_init_type_name(&cm->item, name, &comm_type);
594 
595 	cm->seq = dlm_comm_count++;
596 	if (!cm->seq)
597 		cm->seq = dlm_comm_count++;
598 
599 	cm->nodeid = -1;
600 	cm->local = 0;
601 	cm->addr_count = 0;
602 	return &cm->item;
603 }
604 
605 static void drop_comm(struct config_group *g, struct config_item *i)
606 {
607 	struct dlm_comm *cm = config_item_to_comm(i);
608 	if (local_comm == cm)
609 		local_comm = NULL;
610 	dlm_lowcomms_close(cm->nodeid);
611 	while (cm->addr_count--)
612 		kfree(cm->addr[cm->addr_count]);
613 	config_item_put(i);
614 }
615 
616 static void release_comm(struct config_item *i)
617 {
618 	struct dlm_comm *cm = config_item_to_comm(i);
619 	kfree(cm);
620 }
621 
622 static struct config_item *make_node(struct config_group *g, const char *name)
623 {
624 	struct dlm_space *sp = config_item_to_space(g->cg_item.ci_parent);
625 	struct dlm_node *nd;
626 
627 	nd = kzalloc(sizeof(struct dlm_node), GFP_NOFS);
628 	if (!nd)
629 		return ERR_PTR(-ENOMEM);
630 
631 	config_item_init_type_name(&nd->item, name, &node_type);
632 	nd->nodeid = -1;
633 	nd->weight = 1;  /* default weight of 1 if none is set */
634 	nd->new = 1;     /* set to 0 once it's been read by dlm_nodeid_list() */
635 
636 	mutex_lock(&sp->members_lock);
637 	list_add(&nd->list, &sp->members);
638 	sp->members_count++;
639 	mutex_unlock(&sp->members_lock);
640 
641 	return &nd->item;
642 }
643 
644 static void drop_node(struct config_group *g, struct config_item *i)
645 {
646 	struct dlm_space *sp = config_item_to_space(g->cg_item.ci_parent);
647 	struct dlm_node *nd = config_item_to_node(i);
648 
649 	mutex_lock(&sp->members_lock);
650 	list_del(&nd->list);
651 	sp->members_count--;
652 	mutex_unlock(&sp->members_lock);
653 
654 	config_item_put(i);
655 }
656 
657 static void release_node(struct config_item *i)
658 {
659 	struct dlm_node *nd = config_item_to_node(i);
660 	kfree(nd);
661 }
662 
663 static struct dlm_clusters clusters_root = {
664 	.subsys = {
665 		.su_group = {
666 			.cg_item = {
667 				.ci_namebuf = "dlm",
668 				.ci_type = &clusters_type,
669 			},
670 		},
671 	},
672 };
673 
674 int __init dlm_config_init(void)
675 {
676 	config_group_init(&clusters_root.subsys.su_group);
677 	mutex_init(&clusters_root.subsys.su_mutex);
678 	return configfs_register_subsystem(&clusters_root.subsys);
679 }
680 
681 void dlm_config_exit(void)
682 {
683 	configfs_unregister_subsystem(&clusters_root.subsys);
684 }
685 
686 /*
687  * Functions for user space to read/write attributes
688  */
689 
690 static ssize_t show_cluster(struct config_item *i, struct configfs_attribute *a,
691 			    char *buf)
692 {
693 	struct dlm_cluster *cl = config_item_to_cluster(i);
694 	struct cluster_attribute *cla =
695 			container_of(a, struct cluster_attribute, attr);
696 	return cla->show ? cla->show(cl, buf) : 0;
697 }
698 
699 static ssize_t store_cluster(struct config_item *i,
700 			     struct configfs_attribute *a,
701 			     const char *buf, size_t len)
702 {
703 	struct dlm_cluster *cl = config_item_to_cluster(i);
704 	struct cluster_attribute *cla =
705 		container_of(a, struct cluster_attribute, attr);
706 	return cla->store ? cla->store(cl, buf, len) : -EINVAL;
707 }
708 
709 static ssize_t show_comm(struct config_item *i, struct configfs_attribute *a,
710 			 char *buf)
711 {
712 	struct dlm_comm *cm = config_item_to_comm(i);
713 	struct comm_attribute *cma =
714 			container_of(a, struct comm_attribute, attr);
715 	return cma->show ? cma->show(cm, buf) : 0;
716 }
717 
718 static ssize_t store_comm(struct config_item *i, struct configfs_attribute *a,
719 			  const char *buf, size_t len)
720 {
721 	struct dlm_comm *cm = config_item_to_comm(i);
722 	struct comm_attribute *cma =
723 		container_of(a, struct comm_attribute, attr);
724 	return cma->store ? cma->store(cm, buf, len) : -EINVAL;
725 }
726 
727 static ssize_t comm_nodeid_read(struct dlm_comm *cm, char *buf)
728 {
729 	return sprintf(buf, "%d\n", cm->nodeid);
730 }
731 
732 static ssize_t comm_nodeid_write(struct dlm_comm *cm, const char *buf,
733 				 size_t len)
734 {
735 	int rc = kstrtoint(buf, 0, &cm->nodeid);
736 
737 	if (rc)
738 		return rc;
739 	return len;
740 }
741 
742 static ssize_t comm_local_read(struct dlm_comm *cm, char *buf)
743 {
744 	return sprintf(buf, "%d\n", cm->local);
745 }
746 
747 static ssize_t comm_local_write(struct dlm_comm *cm, const char *buf,
748 				size_t len)
749 {
750 	int rc = kstrtoint(buf, 0, &cm->local);
751 
752 	if (rc)
753 		return rc;
754 	if (cm->local && !local_comm)
755 		local_comm = cm;
756 	return len;
757 }
758 
759 static ssize_t comm_addr_write(struct dlm_comm *cm, const char *buf, size_t len)
760 {
761 	struct sockaddr_storage *addr;
762 	int rv;
763 
764 	if (len != sizeof(struct sockaddr_storage))
765 		return -EINVAL;
766 
767 	if (cm->addr_count >= DLM_MAX_ADDR_COUNT)
768 		return -ENOSPC;
769 
770 	addr = kzalloc(sizeof(*addr), GFP_NOFS);
771 	if (!addr)
772 		return -ENOMEM;
773 
774 	memcpy(addr, buf, len);
775 
776 	rv = dlm_lowcomms_addr(cm->nodeid, addr, len);
777 	if (rv) {
778 		kfree(addr);
779 		return rv;
780 	}
781 
782 	cm->addr[cm->addr_count++] = addr;
783 	return len;
784 }
785 
786 static ssize_t comm_addr_list_read(struct dlm_comm *cm, char *buf)
787 {
788 	ssize_t s;
789 	ssize_t allowance;
790 	int i;
791 	struct sockaddr_storage *addr;
792 	struct sockaddr_in *addr_in;
793 	struct sockaddr_in6 *addr_in6;
794 
795 	/* Taken from ip6_addr_string() defined in lib/vsprintf.c */
796 	char buf0[sizeof("AF_INET6	xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255\n")];
797 
798 
799 	/* Derived from SIMPLE_ATTR_SIZE of fs/configfs/file.c */
800 	allowance = 4096;
801 	buf[0] = '\0';
802 
803 	for (i = 0; i < cm->addr_count; i++) {
804 		addr = cm->addr[i];
805 
806 		switch(addr->ss_family) {
807 		case AF_INET:
808 			addr_in = (struct sockaddr_in *)addr;
809 			s = sprintf(buf0, "AF_INET	%pI4\n", &addr_in->sin_addr.s_addr);
810 			break;
811 		case AF_INET6:
812 			addr_in6 = (struct sockaddr_in6 *)addr;
813 			s = sprintf(buf0, "AF_INET6	%pI6\n", &addr_in6->sin6_addr);
814 			break;
815 		default:
816 			s = sprintf(buf0, "%s\n", "<UNKNOWN>");
817 			break;
818 		}
819 		allowance -= s;
820 		if (allowance >= 0)
821 			strcat(buf, buf0);
822 		else {
823 			allowance += s;
824 			break;
825 		}
826 	}
827 	return 4096 - allowance;
828 }
829 
830 static ssize_t show_node(struct config_item *i, struct configfs_attribute *a,
831 			 char *buf)
832 {
833 	struct dlm_node *nd = config_item_to_node(i);
834 	struct node_attribute *nda =
835 			container_of(a, struct node_attribute, attr);
836 	return nda->show ? nda->show(nd, buf) : 0;
837 }
838 
839 static ssize_t store_node(struct config_item *i, struct configfs_attribute *a,
840 			  const char *buf, size_t len)
841 {
842 	struct dlm_node *nd = config_item_to_node(i);
843 	struct node_attribute *nda =
844 		container_of(a, struct node_attribute, attr);
845 	return nda->store ? nda->store(nd, buf, len) : -EINVAL;
846 }
847 
848 static ssize_t node_nodeid_read(struct dlm_node *nd, char *buf)
849 {
850 	return sprintf(buf, "%d\n", nd->nodeid);
851 }
852 
853 static ssize_t node_nodeid_write(struct dlm_node *nd, const char *buf,
854 				 size_t len)
855 {
856 	uint32_t seq = 0;
857 	int rc = kstrtoint(buf, 0, &nd->nodeid);
858 
859 	if (rc)
860 		return rc;
861 	dlm_comm_seq(nd->nodeid, &seq);
862 	nd->comm_seq = seq;
863 	return len;
864 }
865 
866 static ssize_t node_weight_read(struct dlm_node *nd, char *buf)
867 {
868 	return sprintf(buf, "%d\n", nd->weight);
869 }
870 
871 static ssize_t node_weight_write(struct dlm_node *nd, const char *buf,
872 				 size_t len)
873 {
874 	int rc = kstrtoint(buf, 0, &nd->weight);
875 
876 	if (rc)
877 		return rc;
878 	return len;
879 }
880 
881 /*
882  * Functions for the dlm to get the info that's been configured
883  */
884 
885 static struct dlm_space *get_space(char *name)
886 {
887 	struct config_item *i;
888 
889 	if (!space_list)
890 		return NULL;
891 
892 	mutex_lock(&space_list->cg_subsys->su_mutex);
893 	i = config_group_find_item(space_list, name);
894 	mutex_unlock(&space_list->cg_subsys->su_mutex);
895 
896 	return config_item_to_space(i);
897 }
898 
899 static void put_space(struct dlm_space *sp)
900 {
901 	config_item_put(&sp->group.cg_item);
902 }
903 
904 static struct dlm_comm *get_comm(int nodeid)
905 {
906 	struct config_item *i;
907 	struct dlm_comm *cm = NULL;
908 	int found = 0;
909 
910 	if (!comm_list)
911 		return NULL;
912 
913 	mutex_lock(&clusters_root.subsys.su_mutex);
914 
915 	list_for_each_entry(i, &comm_list->cg_children, ci_entry) {
916 		cm = config_item_to_comm(i);
917 
918 		if (cm->nodeid != nodeid)
919 			continue;
920 		found = 1;
921 		config_item_get(i);
922 		break;
923 	}
924 	mutex_unlock(&clusters_root.subsys.su_mutex);
925 
926 	if (!found)
927 		cm = NULL;
928 	return cm;
929 }
930 
931 static void put_comm(struct dlm_comm *cm)
932 {
933 	config_item_put(&cm->item);
934 }
935 
936 /* caller must free mem */
937 int dlm_config_nodes(char *lsname, struct dlm_config_node **nodes_out,
938 		     int *count_out)
939 {
940 	struct dlm_space *sp;
941 	struct dlm_node *nd;
942 	struct dlm_config_node *nodes, *node;
943 	int rv, count;
944 
945 	sp = get_space(lsname);
946 	if (!sp)
947 		return -EEXIST;
948 
949 	mutex_lock(&sp->members_lock);
950 	if (!sp->members_count) {
951 		rv = -EINVAL;
952 		printk(KERN_ERR "dlm: zero members_count\n");
953 		goto out;
954 	}
955 
956 	count = sp->members_count;
957 
958 	nodes = kcalloc(count, sizeof(struct dlm_config_node), GFP_NOFS);
959 	if (!nodes) {
960 		rv = -ENOMEM;
961 		goto out;
962 	}
963 
964 	node = nodes;
965 	list_for_each_entry(nd, &sp->members, list) {
966 		node->nodeid = nd->nodeid;
967 		node->weight = nd->weight;
968 		node->new = nd->new;
969 		node->comm_seq = nd->comm_seq;
970 		node++;
971 
972 		nd->new = 0;
973 	}
974 
975 	*count_out = count;
976 	*nodes_out = nodes;
977 	rv = 0;
978  out:
979 	mutex_unlock(&sp->members_lock);
980 	put_space(sp);
981 	return rv;
982 }
983 
984 int dlm_comm_seq(int nodeid, uint32_t *seq)
985 {
986 	struct dlm_comm *cm = get_comm(nodeid);
987 	if (!cm)
988 		return -EEXIST;
989 	*seq = cm->seq;
990 	put_comm(cm);
991 	return 0;
992 }
993 
994 int dlm_our_nodeid(void)
995 {
996 	return local_comm ? local_comm->nodeid : 0;
997 }
998 
999 /* num 0 is first addr, num 1 is second addr */
1000 int dlm_our_addr(struct sockaddr_storage *addr, int num)
1001 {
1002 	if (!local_comm)
1003 		return -1;
1004 	if (num + 1 > local_comm->addr_count)
1005 		return -1;
1006 	memcpy(addr, local_comm->addr[num], sizeof(*addr));
1007 	return 0;
1008 }
1009 
1010 /* Config file defaults */
1011 #define DEFAULT_TCP_PORT       21064
1012 #define DEFAULT_BUFFER_SIZE     4096
1013 #define DEFAULT_RSBTBL_SIZE     1024
1014 #define DEFAULT_RECOVER_TIMER      5
1015 #define DEFAULT_TOSS_SECS         10
1016 #define DEFAULT_SCAN_SECS          5
1017 #define DEFAULT_LOG_DEBUG          0
1018 #define DEFAULT_PROTOCOL           0
1019 #define DEFAULT_TIMEWARN_CS      500 /* 5 sec = 500 centiseconds */
1020 #define DEFAULT_WAITWARN_US	   0
1021 #define DEFAULT_NEW_RSB_COUNT    128
1022 #define DEFAULT_RECOVER_CALLBACKS  0
1023 #define DEFAULT_CLUSTER_NAME      ""
1024 
1025 struct dlm_config_info dlm_config = {
1026 	.ci_tcp_port = DEFAULT_TCP_PORT,
1027 	.ci_buffer_size = DEFAULT_BUFFER_SIZE,
1028 	.ci_rsbtbl_size = DEFAULT_RSBTBL_SIZE,
1029 	.ci_recover_timer = DEFAULT_RECOVER_TIMER,
1030 	.ci_toss_secs = DEFAULT_TOSS_SECS,
1031 	.ci_scan_secs = DEFAULT_SCAN_SECS,
1032 	.ci_log_debug = DEFAULT_LOG_DEBUG,
1033 	.ci_protocol = DEFAULT_PROTOCOL,
1034 	.ci_timewarn_cs = DEFAULT_TIMEWARN_CS,
1035 	.ci_waitwarn_us = DEFAULT_WAITWARN_US,
1036 	.ci_new_rsb_count = DEFAULT_NEW_RSB_COUNT,
1037 	.ci_recover_callbacks = DEFAULT_RECOVER_CALLBACKS,
1038 	.ci_cluster_name = DEFAULT_CLUSTER_NAME
1039 };
1040 
1041