xref: /openbmc/linux/fs/dlm/config.c (revision 9cdb81c7)
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_dirtbl_size;
100 	unsigned int cl_recover_timer;
101 	unsigned int cl_toss_secs;
102 	unsigned int cl_scan_secs;
103 	unsigned int cl_log_debug;
104 	unsigned int cl_protocol;
105 	unsigned int cl_timewarn_cs;
106 	unsigned int cl_waitwarn_us;
107 	unsigned int cl_new_rsb_count;
108 	unsigned int cl_recover_callbacks;
109 	char cl_cluster_name[DLM_LOCKSPACE_LEN];
110 };
111 
112 enum {
113 	CLUSTER_ATTR_TCP_PORT = 0,
114 	CLUSTER_ATTR_BUFFER_SIZE,
115 	CLUSTER_ATTR_RSBTBL_SIZE,
116 	CLUSTER_ATTR_DIRTBL_SIZE,
117 	CLUSTER_ATTR_RECOVER_TIMER,
118 	CLUSTER_ATTR_TOSS_SECS,
119 	CLUSTER_ATTR_SCAN_SECS,
120 	CLUSTER_ATTR_LOG_DEBUG,
121 	CLUSTER_ATTR_PROTOCOL,
122 	CLUSTER_ATTR_TIMEWARN_CS,
123 	CLUSTER_ATTR_WAITWARN_US,
124 	CLUSTER_ATTR_NEW_RSB_COUNT,
125 	CLUSTER_ATTR_RECOVER_CALLBACKS,
126 	CLUSTER_ATTR_CLUSTER_NAME,
127 };
128 
129 struct cluster_attribute {
130 	struct configfs_attribute attr;
131 	ssize_t (*show)(struct dlm_cluster *, char *);
132 	ssize_t (*store)(struct dlm_cluster *, const char *, size_t);
133 };
134 
135 static ssize_t cluster_cluster_name_read(struct dlm_cluster *cl, char *buf)
136 {
137 	return sprintf(buf, "%s\n", cl->cl_cluster_name);
138 }
139 
140 static ssize_t cluster_cluster_name_write(struct dlm_cluster *cl,
141 					  const char *buf, size_t len)
142 {
143 	strncpy(dlm_config.ci_cluster_name, buf, DLM_LOCKSPACE_LEN);
144 	strncpy(cl->cl_cluster_name, buf, DLM_LOCKSPACE_LEN);
145 	return len;
146 }
147 
148 static struct cluster_attribute cluster_attr_cluster_name = {
149 	.attr   = { .ca_owner = THIS_MODULE,
150                     .ca_name = "cluster_name",
151                     .ca_mode = S_IRUGO | S_IWUSR },
152 	.show   = cluster_cluster_name_read,
153 	.store  = cluster_cluster_name_write,
154 };
155 
156 static ssize_t cluster_set(struct dlm_cluster *cl, unsigned int *cl_field,
157 			   int *info_field, int check_zero,
158 			   const char *buf, size_t len)
159 {
160 	unsigned int x;
161 
162 	if (!capable(CAP_SYS_ADMIN))
163 		return -EACCES;
164 
165 	x = simple_strtoul(buf, NULL, 0);
166 
167 	if (check_zero && !x)
168 		return -EINVAL;
169 
170 	*cl_field = x;
171 	*info_field = x;
172 
173 	return len;
174 }
175 
176 #define CLUSTER_ATTR(name, check_zero)                                        \
177 static ssize_t name##_write(struct dlm_cluster *cl, const char *buf, size_t len) \
178 {                                                                             \
179 	return cluster_set(cl, &cl->cl_##name, &dlm_config.ci_##name,         \
180 			   check_zero, buf, len);                             \
181 }                                                                             \
182 static ssize_t name##_read(struct dlm_cluster *cl, char *buf)                 \
183 {                                                                             \
184 	return snprintf(buf, PAGE_SIZE, "%u\n", cl->cl_##name);               \
185 }                                                                             \
186 static struct cluster_attribute cluster_attr_##name =                         \
187 __CONFIGFS_ATTR(name, 0644, name##_read, name##_write)
188 
189 CLUSTER_ATTR(tcp_port, 1);
190 CLUSTER_ATTR(buffer_size, 1);
191 CLUSTER_ATTR(rsbtbl_size, 1);
192 CLUSTER_ATTR(dirtbl_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_DIRTBL_SIZE] = &cluster_attr_dirtbl_size.attr,
208 	[CLUSTER_ATTR_RECOVER_TIMER] = &cluster_attr_recover_timer.attr,
209 	[CLUSTER_ATTR_TOSS_SECS] = &cluster_attr_toss_secs.attr,
210 	[CLUSTER_ATTR_SCAN_SECS] = &cluster_attr_scan_secs.attr,
211 	[CLUSTER_ATTR_LOG_DEBUG] = &cluster_attr_log_debug.attr,
212 	[CLUSTER_ATTR_PROTOCOL] = &cluster_attr_protocol.attr,
213 	[CLUSTER_ATTR_TIMEWARN_CS] = &cluster_attr_timewarn_cs.attr,
214 	[CLUSTER_ATTR_WAITWARN_US] = &cluster_attr_waitwarn_us.attr,
215 	[CLUSTER_ATTR_NEW_RSB_COUNT] = &cluster_attr_new_rsb_count.attr,
216 	[CLUSTER_ATTR_RECOVER_CALLBACKS] = &cluster_attr_recover_callbacks.attr,
217 	[CLUSTER_ATTR_CLUSTER_NAME] = &cluster_attr_cluster_name.attr,
218 	NULL,
219 };
220 
221 enum {
222 	COMM_ATTR_NODEID = 0,
223 	COMM_ATTR_LOCAL,
224 	COMM_ATTR_ADDR,
225 	COMM_ATTR_ADDR_LIST,
226 };
227 
228 struct comm_attribute {
229 	struct configfs_attribute attr;
230 	ssize_t (*show)(struct dlm_comm *, char *);
231 	ssize_t (*store)(struct dlm_comm *, const char *, size_t);
232 };
233 
234 static struct comm_attribute comm_attr_nodeid = {
235 	.attr   = { .ca_owner = THIS_MODULE,
236                     .ca_name = "nodeid",
237                     .ca_mode = S_IRUGO | S_IWUSR },
238 	.show   = comm_nodeid_read,
239 	.store  = comm_nodeid_write,
240 };
241 
242 static struct comm_attribute comm_attr_local = {
243 	.attr   = { .ca_owner = THIS_MODULE,
244                     .ca_name = "local",
245                     .ca_mode = S_IRUGO | S_IWUSR },
246 	.show   = comm_local_read,
247 	.store  = comm_local_write,
248 };
249 
250 static struct comm_attribute comm_attr_addr = {
251 	.attr   = { .ca_owner = THIS_MODULE,
252                     .ca_name = "addr",
253                     .ca_mode = S_IWUSR },
254 	.store  = comm_addr_write,
255 };
256 
257 static struct comm_attribute comm_attr_addr_list = {
258 	.attr   = { .ca_owner = THIS_MODULE,
259                     .ca_name = "addr_list",
260                     .ca_mode = S_IRUGO },
261 	.show   = comm_addr_list_read,
262 };
263 
264 static struct configfs_attribute *comm_attrs[] = {
265 	[COMM_ATTR_NODEID] = &comm_attr_nodeid.attr,
266 	[COMM_ATTR_LOCAL] = &comm_attr_local.attr,
267 	[COMM_ATTR_ADDR] = &comm_attr_addr.attr,
268 	[COMM_ATTR_ADDR_LIST] = &comm_attr_addr_list.attr,
269 	NULL,
270 };
271 
272 enum {
273 	NODE_ATTR_NODEID = 0,
274 	NODE_ATTR_WEIGHT,
275 };
276 
277 struct node_attribute {
278 	struct configfs_attribute attr;
279 	ssize_t (*show)(struct dlm_node *, char *);
280 	ssize_t (*store)(struct dlm_node *, const char *, size_t);
281 };
282 
283 static struct node_attribute node_attr_nodeid = {
284 	.attr   = { .ca_owner = THIS_MODULE,
285                     .ca_name = "nodeid",
286                     .ca_mode = S_IRUGO | S_IWUSR },
287 	.show   = node_nodeid_read,
288 	.store  = node_nodeid_write,
289 };
290 
291 static struct node_attribute node_attr_weight = {
292 	.attr   = { .ca_owner = THIS_MODULE,
293                     .ca_name = "weight",
294                     .ca_mode = S_IRUGO | S_IWUSR },
295 	.show   = node_weight_read,
296 	.store  = node_weight_write,
297 };
298 
299 static struct configfs_attribute *node_attrs[] = {
300 	[NODE_ATTR_NODEID] = &node_attr_nodeid.attr,
301 	[NODE_ATTR_WEIGHT] = &node_attr_weight.attr,
302 	NULL,
303 };
304 
305 struct dlm_clusters {
306 	struct configfs_subsystem subsys;
307 };
308 
309 struct dlm_spaces {
310 	struct config_group ss_group;
311 };
312 
313 struct dlm_space {
314 	struct config_group group;
315 	struct list_head members;
316 	struct mutex members_lock;
317 	int members_count;
318 };
319 
320 struct dlm_comms {
321 	struct config_group cs_group;
322 };
323 
324 struct dlm_comm {
325 	struct config_item item;
326 	int seq;
327 	int nodeid;
328 	int local;
329 	int addr_count;
330 	struct sockaddr_storage *addr[DLM_MAX_ADDR_COUNT];
331 };
332 
333 struct dlm_nodes {
334 	struct config_group ns_group;
335 };
336 
337 struct dlm_node {
338 	struct config_item item;
339 	struct list_head list; /* space->members */
340 	int nodeid;
341 	int weight;
342 	int new;
343 	int comm_seq; /* copy of cm->seq when nd->nodeid is set */
344 };
345 
346 static struct configfs_group_operations clusters_ops = {
347 	.make_group = make_cluster,
348 	.drop_item = drop_cluster,
349 };
350 
351 static struct configfs_item_operations cluster_ops = {
352 	.release = release_cluster,
353 	.show_attribute = show_cluster,
354 	.store_attribute = store_cluster,
355 };
356 
357 static struct configfs_group_operations spaces_ops = {
358 	.make_group = make_space,
359 	.drop_item = drop_space,
360 };
361 
362 static struct configfs_item_operations space_ops = {
363 	.release = release_space,
364 };
365 
366 static struct configfs_group_operations comms_ops = {
367 	.make_item = make_comm,
368 	.drop_item = drop_comm,
369 };
370 
371 static struct configfs_item_operations comm_ops = {
372 	.release = release_comm,
373 	.show_attribute = show_comm,
374 	.store_attribute = store_comm,
375 };
376 
377 static struct configfs_group_operations nodes_ops = {
378 	.make_item = make_node,
379 	.drop_item = drop_node,
380 };
381 
382 static struct configfs_item_operations node_ops = {
383 	.release = release_node,
384 	.show_attribute = show_node,
385 	.store_attribute = store_node,
386 };
387 
388 static struct config_item_type clusters_type = {
389 	.ct_group_ops = &clusters_ops,
390 	.ct_owner = THIS_MODULE,
391 };
392 
393 static struct config_item_type cluster_type = {
394 	.ct_item_ops = &cluster_ops,
395 	.ct_attrs = cluster_attrs,
396 	.ct_owner = THIS_MODULE,
397 };
398 
399 static struct config_item_type spaces_type = {
400 	.ct_group_ops = &spaces_ops,
401 	.ct_owner = THIS_MODULE,
402 };
403 
404 static struct config_item_type space_type = {
405 	.ct_item_ops = &space_ops,
406 	.ct_owner = THIS_MODULE,
407 };
408 
409 static struct config_item_type comms_type = {
410 	.ct_group_ops = &comms_ops,
411 	.ct_owner = THIS_MODULE,
412 };
413 
414 static struct config_item_type comm_type = {
415 	.ct_item_ops = &comm_ops,
416 	.ct_attrs = comm_attrs,
417 	.ct_owner = THIS_MODULE,
418 };
419 
420 static struct config_item_type nodes_type = {
421 	.ct_group_ops = &nodes_ops,
422 	.ct_owner = THIS_MODULE,
423 };
424 
425 static struct config_item_type node_type = {
426 	.ct_item_ops = &node_ops,
427 	.ct_attrs = node_attrs,
428 	.ct_owner = THIS_MODULE,
429 };
430 
431 static struct dlm_cluster *config_item_to_cluster(struct config_item *i)
432 {
433 	return i ? container_of(to_config_group(i), struct dlm_cluster, group) :
434 		   NULL;
435 }
436 
437 static struct dlm_space *config_item_to_space(struct config_item *i)
438 {
439 	return i ? container_of(to_config_group(i), struct dlm_space, group) :
440 		   NULL;
441 }
442 
443 static struct dlm_comm *config_item_to_comm(struct config_item *i)
444 {
445 	return i ? container_of(i, struct dlm_comm, item) : NULL;
446 }
447 
448 static struct dlm_node *config_item_to_node(struct config_item *i)
449 {
450 	return i ? container_of(i, struct dlm_node, item) : NULL;
451 }
452 
453 static struct config_group *make_cluster(struct config_group *g,
454 					 const char *name)
455 {
456 	struct dlm_cluster *cl = NULL;
457 	struct dlm_spaces *sps = NULL;
458 	struct dlm_comms *cms = NULL;
459 	void *gps = NULL;
460 
461 	cl = kzalloc(sizeof(struct dlm_cluster), GFP_NOFS);
462 	gps = kcalloc(3, sizeof(struct config_group *), GFP_NOFS);
463 	sps = kzalloc(sizeof(struct dlm_spaces), GFP_NOFS);
464 	cms = kzalloc(sizeof(struct dlm_comms), GFP_NOFS);
465 
466 	if (!cl || !gps || !sps || !cms)
467 		goto fail;
468 
469 	config_group_init_type_name(&cl->group, name, &cluster_type);
470 	config_group_init_type_name(&sps->ss_group, "spaces", &spaces_type);
471 	config_group_init_type_name(&cms->cs_group, "comms", &comms_type);
472 
473 	cl->group.default_groups = gps;
474 	cl->group.default_groups[0] = &sps->ss_group;
475 	cl->group.default_groups[1] = &cms->cs_group;
476 	cl->group.default_groups[2] = NULL;
477 
478 	cl->cl_tcp_port = dlm_config.ci_tcp_port;
479 	cl->cl_buffer_size = dlm_config.ci_buffer_size;
480 	cl->cl_rsbtbl_size = dlm_config.ci_rsbtbl_size;
481 	cl->cl_dirtbl_size = dlm_config.ci_dirtbl_size;
482 	cl->cl_recover_timer = dlm_config.ci_recover_timer;
483 	cl->cl_toss_secs = dlm_config.ci_toss_secs;
484 	cl->cl_scan_secs = dlm_config.ci_scan_secs;
485 	cl->cl_log_debug = dlm_config.ci_log_debug;
486 	cl->cl_protocol = dlm_config.ci_protocol;
487 	cl->cl_timewarn_cs = dlm_config.ci_timewarn_cs;
488 	cl->cl_waitwarn_us = dlm_config.ci_waitwarn_us;
489 	cl->cl_new_rsb_count = dlm_config.ci_new_rsb_count;
490 	cl->cl_recover_callbacks = dlm_config.ci_recover_callbacks;
491 	memcpy(cl->cl_cluster_name, dlm_config.ci_cluster_name,
492 	       DLM_LOCKSPACE_LEN);
493 
494 	space_list = &sps->ss_group;
495 	comm_list = &cms->cs_group;
496 	return &cl->group;
497 
498  fail:
499 	kfree(cl);
500 	kfree(gps);
501 	kfree(sps);
502 	kfree(cms);
503 	return ERR_PTR(-ENOMEM);
504 }
505 
506 static void drop_cluster(struct config_group *g, struct config_item *i)
507 {
508 	struct dlm_cluster *cl = config_item_to_cluster(i);
509 	struct config_item *tmp;
510 	int j;
511 
512 	for (j = 0; cl->group.default_groups[j]; j++) {
513 		tmp = &cl->group.default_groups[j]->cg_item;
514 		cl->group.default_groups[j] = NULL;
515 		config_item_put(tmp);
516 	}
517 
518 	space_list = NULL;
519 	comm_list = NULL;
520 
521 	config_item_put(i);
522 }
523 
524 static void release_cluster(struct config_item *i)
525 {
526 	struct dlm_cluster *cl = config_item_to_cluster(i);
527 	kfree(cl->group.default_groups);
528 	kfree(cl);
529 }
530 
531 static struct config_group *make_space(struct config_group *g, const char *name)
532 {
533 	struct dlm_space *sp = NULL;
534 	struct dlm_nodes *nds = NULL;
535 	void *gps = NULL;
536 
537 	sp = kzalloc(sizeof(struct dlm_space), GFP_NOFS);
538 	gps = kcalloc(2, sizeof(struct config_group *), GFP_NOFS);
539 	nds = kzalloc(sizeof(struct dlm_nodes), GFP_NOFS);
540 
541 	if (!sp || !gps || !nds)
542 		goto fail;
543 
544 	config_group_init_type_name(&sp->group, name, &space_type);
545 	config_group_init_type_name(&nds->ns_group, "nodes", &nodes_type);
546 
547 	sp->group.default_groups = gps;
548 	sp->group.default_groups[0] = &nds->ns_group;
549 	sp->group.default_groups[1] = NULL;
550 
551 	INIT_LIST_HEAD(&sp->members);
552 	mutex_init(&sp->members_lock);
553 	sp->members_count = 0;
554 	return &sp->group;
555 
556  fail:
557 	kfree(sp);
558 	kfree(gps);
559 	kfree(nds);
560 	return ERR_PTR(-ENOMEM);
561 }
562 
563 static void drop_space(struct config_group *g, struct config_item *i)
564 {
565 	struct dlm_space *sp = config_item_to_space(i);
566 	struct config_item *tmp;
567 	int j;
568 
569 	/* assert list_empty(&sp->members) */
570 
571 	for (j = 0; sp->group.default_groups[j]; j++) {
572 		tmp = &sp->group.default_groups[j]->cg_item;
573 		sp->group.default_groups[j] = NULL;
574 		config_item_put(tmp);
575 	}
576 
577 	config_item_put(i);
578 }
579 
580 static void release_space(struct config_item *i)
581 {
582 	struct dlm_space *sp = config_item_to_space(i);
583 	kfree(sp->group.default_groups);
584 	kfree(sp);
585 }
586 
587 static struct config_item *make_comm(struct config_group *g, const char *name)
588 {
589 	struct dlm_comm *cm;
590 
591 	cm = kzalloc(sizeof(struct dlm_comm), GFP_NOFS);
592 	if (!cm)
593 		return ERR_PTR(-ENOMEM);
594 
595 	config_item_init_type_name(&cm->item, name, &comm_type);
596 
597 	cm->seq = dlm_comm_count++;
598 	if (!cm->seq)
599 		cm->seq = dlm_comm_count++;
600 
601 	cm->nodeid = -1;
602 	cm->local = 0;
603 	cm->addr_count = 0;
604 	return &cm->item;
605 }
606 
607 static void drop_comm(struct config_group *g, struct config_item *i)
608 {
609 	struct dlm_comm *cm = config_item_to_comm(i);
610 	if (local_comm == cm)
611 		local_comm = NULL;
612 	dlm_lowcomms_close(cm->nodeid);
613 	while (cm->addr_count--)
614 		kfree(cm->addr[cm->addr_count]);
615 	config_item_put(i);
616 }
617 
618 static void release_comm(struct config_item *i)
619 {
620 	struct dlm_comm *cm = config_item_to_comm(i);
621 	kfree(cm);
622 }
623 
624 static struct config_item *make_node(struct config_group *g, const char *name)
625 {
626 	struct dlm_space *sp = config_item_to_space(g->cg_item.ci_parent);
627 	struct dlm_node *nd;
628 
629 	nd = kzalloc(sizeof(struct dlm_node), GFP_NOFS);
630 	if (!nd)
631 		return ERR_PTR(-ENOMEM);
632 
633 	config_item_init_type_name(&nd->item, name, &node_type);
634 	nd->nodeid = -1;
635 	nd->weight = 1;  /* default weight of 1 if none is set */
636 	nd->new = 1;     /* set to 0 once it's been read by dlm_nodeid_list() */
637 
638 	mutex_lock(&sp->members_lock);
639 	list_add(&nd->list, &sp->members);
640 	sp->members_count++;
641 	mutex_unlock(&sp->members_lock);
642 
643 	return &nd->item;
644 }
645 
646 static void drop_node(struct config_group *g, struct config_item *i)
647 {
648 	struct dlm_space *sp = config_item_to_space(g->cg_item.ci_parent);
649 	struct dlm_node *nd = config_item_to_node(i);
650 
651 	mutex_lock(&sp->members_lock);
652 	list_del(&nd->list);
653 	sp->members_count--;
654 	mutex_unlock(&sp->members_lock);
655 
656 	config_item_put(i);
657 }
658 
659 static void release_node(struct config_item *i)
660 {
661 	struct dlm_node *nd = config_item_to_node(i);
662 	kfree(nd);
663 }
664 
665 static struct dlm_clusters clusters_root = {
666 	.subsys = {
667 		.su_group = {
668 			.cg_item = {
669 				.ci_namebuf = "dlm",
670 				.ci_type = &clusters_type,
671 			},
672 		},
673 	},
674 };
675 
676 int __init dlm_config_init(void)
677 {
678 	config_group_init(&clusters_root.subsys.su_group);
679 	mutex_init(&clusters_root.subsys.su_mutex);
680 	return configfs_register_subsystem(&clusters_root.subsys);
681 }
682 
683 void dlm_config_exit(void)
684 {
685 	configfs_unregister_subsystem(&clusters_root.subsys);
686 }
687 
688 /*
689  * Functions for user space to read/write attributes
690  */
691 
692 static ssize_t show_cluster(struct config_item *i, struct configfs_attribute *a,
693 			    char *buf)
694 {
695 	struct dlm_cluster *cl = config_item_to_cluster(i);
696 	struct cluster_attribute *cla =
697 			container_of(a, struct cluster_attribute, attr);
698 	return cla->show ? cla->show(cl, buf) : 0;
699 }
700 
701 static ssize_t store_cluster(struct config_item *i,
702 			     struct configfs_attribute *a,
703 			     const char *buf, size_t len)
704 {
705 	struct dlm_cluster *cl = config_item_to_cluster(i);
706 	struct cluster_attribute *cla =
707 		container_of(a, struct cluster_attribute, attr);
708 	return cla->store ? cla->store(cl, buf, len) : -EINVAL;
709 }
710 
711 static ssize_t show_comm(struct config_item *i, struct configfs_attribute *a,
712 			 char *buf)
713 {
714 	struct dlm_comm *cm = config_item_to_comm(i);
715 	struct comm_attribute *cma =
716 			container_of(a, struct comm_attribute, attr);
717 	return cma->show ? cma->show(cm, buf) : 0;
718 }
719 
720 static ssize_t store_comm(struct config_item *i, struct configfs_attribute *a,
721 			  const char *buf, size_t len)
722 {
723 	struct dlm_comm *cm = config_item_to_comm(i);
724 	struct comm_attribute *cma =
725 		container_of(a, struct comm_attribute, attr);
726 	return cma->store ? cma->store(cm, buf, len) : -EINVAL;
727 }
728 
729 static ssize_t comm_nodeid_read(struct dlm_comm *cm, char *buf)
730 {
731 	return sprintf(buf, "%d\n", cm->nodeid);
732 }
733 
734 static ssize_t comm_nodeid_write(struct dlm_comm *cm, const char *buf,
735 				 size_t len)
736 {
737 	cm->nodeid = simple_strtol(buf, NULL, 0);
738 	return len;
739 }
740 
741 static ssize_t comm_local_read(struct dlm_comm *cm, char *buf)
742 {
743 	return sprintf(buf, "%d\n", cm->local);
744 }
745 
746 static ssize_t comm_local_write(struct dlm_comm *cm, const char *buf,
747 				size_t len)
748 {
749 	cm->local= simple_strtol(buf, NULL, 0);
750 	if (cm->local && !local_comm)
751 		local_comm = cm;
752 	return len;
753 }
754 
755 static ssize_t comm_addr_write(struct dlm_comm *cm, const char *buf, size_t len)
756 {
757 	struct sockaddr_storage *addr;
758 
759 	if (len != sizeof(struct sockaddr_storage))
760 		return -EINVAL;
761 
762 	if (cm->addr_count >= DLM_MAX_ADDR_COUNT)
763 		return -ENOSPC;
764 
765 	addr = kzalloc(sizeof(*addr), GFP_NOFS);
766 	if (!addr)
767 		return -ENOMEM;
768 
769 	memcpy(addr, buf, len);
770 	cm->addr[cm->addr_count++] = addr;
771 	return len;
772 }
773 
774 static ssize_t comm_addr_list_read(struct dlm_comm *cm, char *buf)
775 {
776 	ssize_t s;
777 	ssize_t allowance;
778 	int i;
779 	struct sockaddr_storage *addr;
780 	struct sockaddr_in *addr_in;
781 	struct sockaddr_in6 *addr_in6;
782 
783 	/* Taken from ip6_addr_string() defined in lib/vsprintf.c */
784 	char buf0[sizeof("AF_INET6	xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255\n")];
785 
786 
787 	/* Derived from SIMPLE_ATTR_SIZE of fs/configfs/file.c */
788 	allowance = 4096;
789 	buf[0] = '\0';
790 
791 	for (i = 0; i < cm->addr_count; i++) {
792 		addr = cm->addr[i];
793 
794 		switch(addr->ss_family) {
795 		case AF_INET:
796 			addr_in = (struct sockaddr_in *)addr;
797 			s = sprintf(buf0, "AF_INET	%pI4\n", &addr_in->sin_addr.s_addr);
798 			break;
799 		case AF_INET6:
800 			addr_in6 = (struct sockaddr_in6 *)addr;
801 			s = sprintf(buf0, "AF_INET6	%pI6\n", &addr_in6->sin6_addr);
802 			break;
803 		default:
804 			s = sprintf(buf0, "%s\n", "<UNKNOWN>");
805 			break;
806 		}
807 		allowance -= s;
808 		if (allowance >= 0)
809 			strcat(buf, buf0);
810 		else {
811 			allowance += s;
812 			break;
813 		}
814 	}
815 	return 4096 - allowance;
816 }
817 
818 static ssize_t show_node(struct config_item *i, struct configfs_attribute *a,
819 			 char *buf)
820 {
821 	struct dlm_node *nd = config_item_to_node(i);
822 	struct node_attribute *nda =
823 			container_of(a, struct node_attribute, attr);
824 	return nda->show ? nda->show(nd, buf) : 0;
825 }
826 
827 static ssize_t store_node(struct config_item *i, struct configfs_attribute *a,
828 			  const char *buf, size_t len)
829 {
830 	struct dlm_node *nd = config_item_to_node(i);
831 	struct node_attribute *nda =
832 		container_of(a, struct node_attribute, attr);
833 	return nda->store ? nda->store(nd, buf, len) : -EINVAL;
834 }
835 
836 static ssize_t node_nodeid_read(struct dlm_node *nd, char *buf)
837 {
838 	return sprintf(buf, "%d\n", nd->nodeid);
839 }
840 
841 static ssize_t node_nodeid_write(struct dlm_node *nd, const char *buf,
842 				 size_t len)
843 {
844 	uint32_t seq = 0;
845 	nd->nodeid = simple_strtol(buf, NULL, 0);
846 	dlm_comm_seq(nd->nodeid, &seq);
847 	nd->comm_seq = seq;
848 	return len;
849 }
850 
851 static ssize_t node_weight_read(struct dlm_node *nd, char *buf)
852 {
853 	return sprintf(buf, "%d\n", nd->weight);
854 }
855 
856 static ssize_t node_weight_write(struct dlm_node *nd, const char *buf,
857 				 size_t len)
858 {
859 	nd->weight = simple_strtol(buf, NULL, 0);
860 	return len;
861 }
862 
863 /*
864  * Functions for the dlm to get the info that's been configured
865  */
866 
867 static struct dlm_space *get_space(char *name)
868 {
869 	struct config_item *i;
870 
871 	if (!space_list)
872 		return NULL;
873 
874 	mutex_lock(&space_list->cg_subsys->su_mutex);
875 	i = config_group_find_item(space_list, name);
876 	mutex_unlock(&space_list->cg_subsys->su_mutex);
877 
878 	return config_item_to_space(i);
879 }
880 
881 static void put_space(struct dlm_space *sp)
882 {
883 	config_item_put(&sp->group.cg_item);
884 }
885 
886 static int addr_compare(struct sockaddr_storage *x, struct sockaddr_storage *y)
887 {
888 	switch (x->ss_family) {
889 	case AF_INET: {
890 		struct sockaddr_in *sinx = (struct sockaddr_in *)x;
891 		struct sockaddr_in *siny = (struct sockaddr_in *)y;
892 		if (sinx->sin_addr.s_addr != siny->sin_addr.s_addr)
893 			return 0;
894 		if (sinx->sin_port != siny->sin_port)
895 			return 0;
896 		break;
897 	}
898 	case AF_INET6: {
899 		struct sockaddr_in6 *sinx = (struct sockaddr_in6 *)x;
900 		struct sockaddr_in6 *siny = (struct sockaddr_in6 *)y;
901 		if (!ipv6_addr_equal(&sinx->sin6_addr, &siny->sin6_addr))
902 			return 0;
903 		if (sinx->sin6_port != siny->sin6_port)
904 			return 0;
905 		break;
906 	}
907 	default:
908 		return 0;
909 	}
910 	return 1;
911 }
912 
913 static struct dlm_comm *get_comm(int nodeid, struct sockaddr_storage *addr)
914 {
915 	struct config_item *i;
916 	struct dlm_comm *cm = NULL;
917 	int found = 0;
918 
919 	if (!comm_list)
920 		return NULL;
921 
922 	mutex_lock(&clusters_root.subsys.su_mutex);
923 
924 	list_for_each_entry(i, &comm_list->cg_children, ci_entry) {
925 		cm = config_item_to_comm(i);
926 
927 		if (nodeid) {
928 			if (cm->nodeid != nodeid)
929 				continue;
930 			found = 1;
931 			config_item_get(i);
932 			break;
933 		} else {
934 			if (!cm->addr_count || !addr_compare(cm->addr[0], addr))
935 				continue;
936 			found = 1;
937 			config_item_get(i);
938 			break;
939 		}
940 	}
941 	mutex_unlock(&clusters_root.subsys.su_mutex);
942 
943 	if (!found)
944 		cm = NULL;
945 	return cm;
946 }
947 
948 static void put_comm(struct dlm_comm *cm)
949 {
950 	config_item_put(&cm->item);
951 }
952 
953 /* caller must free mem */
954 int dlm_config_nodes(char *lsname, struct dlm_config_node **nodes_out,
955 		     int *count_out)
956 {
957 	struct dlm_space *sp;
958 	struct dlm_node *nd;
959 	struct dlm_config_node *nodes, *node;
960 	int rv, count;
961 
962 	sp = get_space(lsname);
963 	if (!sp)
964 		return -EEXIST;
965 
966 	mutex_lock(&sp->members_lock);
967 	if (!sp->members_count) {
968 		rv = -EINVAL;
969 		printk(KERN_ERR "dlm: zero members_count\n");
970 		goto out;
971 	}
972 
973 	count = sp->members_count;
974 
975 	nodes = kcalloc(count, sizeof(struct dlm_config_node), GFP_NOFS);
976 	if (!nodes) {
977 		rv = -ENOMEM;
978 		goto out;
979 	}
980 
981 	node = nodes;
982 	list_for_each_entry(nd, &sp->members, list) {
983 		node->nodeid = nd->nodeid;
984 		node->weight = nd->weight;
985 		node->new = nd->new;
986 		node->comm_seq = nd->comm_seq;
987 		node++;
988 
989 		nd->new = 0;
990 	}
991 
992 	*count_out = count;
993 	*nodes_out = nodes;
994 	rv = 0;
995  out:
996 	mutex_unlock(&sp->members_lock);
997 	put_space(sp);
998 	return rv;
999 }
1000 
1001 int dlm_comm_seq(int nodeid, uint32_t *seq)
1002 {
1003 	struct dlm_comm *cm = get_comm(nodeid, NULL);
1004 	if (!cm)
1005 		return -EEXIST;
1006 	*seq = cm->seq;
1007 	put_comm(cm);
1008 	return 0;
1009 }
1010 
1011 int dlm_nodeid_to_addr(int nodeid, struct sockaddr_storage *addr)
1012 {
1013 	struct dlm_comm *cm = get_comm(nodeid, NULL);
1014 	if (!cm)
1015 		return -EEXIST;
1016 	if (!cm->addr_count)
1017 		return -ENOENT;
1018 	memcpy(addr, cm->addr[0], sizeof(*addr));
1019 	put_comm(cm);
1020 	return 0;
1021 }
1022 
1023 int dlm_addr_to_nodeid(struct sockaddr_storage *addr, int *nodeid)
1024 {
1025 	struct dlm_comm *cm = get_comm(0, addr);
1026 	if (!cm)
1027 		return -EEXIST;
1028 	*nodeid = cm->nodeid;
1029 	put_comm(cm);
1030 	return 0;
1031 }
1032 
1033 int dlm_our_nodeid(void)
1034 {
1035 	return local_comm ? local_comm->nodeid : 0;
1036 }
1037 
1038 /* num 0 is first addr, num 1 is second addr */
1039 int dlm_our_addr(struct sockaddr_storage *addr, int num)
1040 {
1041 	if (!local_comm)
1042 		return -1;
1043 	if (num + 1 > local_comm->addr_count)
1044 		return -1;
1045 	memcpy(addr, local_comm->addr[num], sizeof(*addr));
1046 	return 0;
1047 }
1048 
1049 /* Config file defaults */
1050 #define DEFAULT_TCP_PORT       21064
1051 #define DEFAULT_BUFFER_SIZE     4096
1052 #define DEFAULT_RSBTBL_SIZE     1024
1053 #define DEFAULT_DIRTBL_SIZE     1024
1054 #define DEFAULT_RECOVER_TIMER      5
1055 #define DEFAULT_TOSS_SECS         10
1056 #define DEFAULT_SCAN_SECS          5
1057 #define DEFAULT_LOG_DEBUG          0
1058 #define DEFAULT_PROTOCOL           0
1059 #define DEFAULT_TIMEWARN_CS      500 /* 5 sec = 500 centiseconds */
1060 #define DEFAULT_WAITWARN_US	   0
1061 #define DEFAULT_NEW_RSB_COUNT    128
1062 #define DEFAULT_RECOVER_CALLBACKS  0
1063 #define DEFAULT_CLUSTER_NAME      ""
1064 
1065 struct dlm_config_info dlm_config = {
1066 	.ci_tcp_port = DEFAULT_TCP_PORT,
1067 	.ci_buffer_size = DEFAULT_BUFFER_SIZE,
1068 	.ci_rsbtbl_size = DEFAULT_RSBTBL_SIZE,
1069 	.ci_dirtbl_size = DEFAULT_DIRTBL_SIZE,
1070 	.ci_recover_timer = DEFAULT_RECOVER_TIMER,
1071 	.ci_toss_secs = DEFAULT_TOSS_SECS,
1072 	.ci_scan_secs = DEFAULT_SCAN_SECS,
1073 	.ci_log_debug = DEFAULT_LOG_DEBUG,
1074 	.ci_protocol = DEFAULT_PROTOCOL,
1075 	.ci_timewarn_cs = DEFAULT_TIMEWARN_CS,
1076 	.ci_waitwarn_us = DEFAULT_WAITWARN_US,
1077 	.ci_new_rsb_count = DEFAULT_NEW_RSB_COUNT,
1078 	.ci_recover_callbacks = DEFAULT_RECOVER_CALLBACKS,
1079 	.ci_cluster_name = DEFAULT_CLUSTER_NAME
1080 };
1081 
1082