1 // SPDX-License-Identifier: GPL-2.0-only
2 /******************************************************************************
3 *******************************************************************************
4 **
5 **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
6 **  Copyright (C) 2004-2011 Red Hat, Inc.  All rights reserved.
7 **
8 **
9 *******************************************************************************
10 ******************************************************************************/
11 
12 #include <linux/kernel.h>
13 #include <linux/init.h>
14 #include <linux/configfs.h>
15 #include <linux/slab.h>
16 #include <linux/in.h>
17 #include <linux/in6.h>
18 #include <linux/dlmconstants.h>
19 #include <net/ipv6.h>
20 #include <net/sock.h>
21 
22 #include "config.h"
23 #include "midcomms.h"
24 #include "lowcomms.h"
25 
26 /*
27  * /config/dlm/<cluster>/spaces/<space>/nodes/<node>/nodeid (refers to <node>)
28  * /config/dlm/<cluster>/spaces/<space>/nodes/<node>/weight
29  * /config/dlm/<cluster>/comms/<comm>/nodeid (refers to <comm>)
30  * /config/dlm/<cluster>/comms/<comm>/local
31  * /config/dlm/<cluster>/comms/<comm>/addr      (write only)
32  * /config/dlm/<cluster>/comms/<comm>/addr_list (read only)
33  * The <cluster> level is useless, but I haven't figured out how to avoid it.
34  */
35 
36 static struct config_group *space_list;
37 static struct config_group *comm_list;
38 static struct dlm_comm *local_comm;
39 static uint32_t dlm_comm_count;
40 
41 struct dlm_clusters;
42 struct dlm_cluster;
43 struct dlm_spaces;
44 struct dlm_space;
45 struct dlm_comms;
46 struct dlm_comm;
47 struct dlm_nodes;
48 struct dlm_node;
49 
50 static struct config_group *make_cluster(struct config_group *, const char *);
51 static void drop_cluster(struct config_group *, struct config_item *);
52 static void release_cluster(struct config_item *);
53 static struct config_group *make_space(struct config_group *, const char *);
54 static void drop_space(struct config_group *, struct config_item *);
55 static void release_space(struct config_item *);
56 static struct config_item *make_comm(struct config_group *, const char *);
57 static void drop_comm(struct config_group *, struct config_item *);
58 static void release_comm(struct config_item *);
59 static struct config_item *make_node(struct config_group *, const char *);
60 static void drop_node(struct config_group *, struct config_item *);
61 static void release_node(struct config_item *);
62 
63 static struct configfs_attribute *comm_attrs[];
64 static struct configfs_attribute *node_attrs[];
65 
66 const struct rhashtable_params dlm_rhash_rsb_params = {
67 	.nelem_hint = 3, /* start small */
68 	.key_len = DLM_RESNAME_MAXLEN,
69 	.key_offset = offsetof(struct dlm_rsb, res_name),
70 	.head_offset = offsetof(struct dlm_rsb, res_node),
71 	.automatic_shrinking = true,
72 };
73 
74 struct dlm_cluster {
75 	struct config_group group;
76 	struct dlm_spaces *sps;
77 	struct dlm_comms *cms;
78 };
79 
80 static struct dlm_cluster *config_item_to_cluster(struct config_item *i)
81 {
82 	return i ? container_of(to_config_group(i), struct dlm_cluster, group) :
83 		   NULL;
84 }
85 
86 enum {
87 	CLUSTER_ATTR_TCP_PORT = 0,
88 	CLUSTER_ATTR_BUFFER_SIZE,
89 	CLUSTER_ATTR_RSBTBL_SIZE,
90 	CLUSTER_ATTR_RECOVER_TIMER,
91 	CLUSTER_ATTR_TOSS_SECS,
92 	CLUSTER_ATTR_SCAN_SECS,
93 	CLUSTER_ATTR_LOG_DEBUG,
94 	CLUSTER_ATTR_LOG_INFO,
95 	CLUSTER_ATTR_PROTOCOL,
96 	CLUSTER_ATTR_MARK,
97 	CLUSTER_ATTR_NEW_RSB_COUNT,
98 	CLUSTER_ATTR_RECOVER_CALLBACKS,
99 	CLUSTER_ATTR_CLUSTER_NAME,
100 };
101 
102 static ssize_t cluster_cluster_name_show(struct config_item *item, char *buf)
103 {
104 	return sprintf(buf, "%s\n", dlm_config.ci_cluster_name);
105 }
106 
107 static ssize_t cluster_cluster_name_store(struct config_item *item,
108 					  const char *buf, size_t len)
109 {
110 	strscpy(dlm_config.ci_cluster_name, buf,
111 		sizeof(dlm_config.ci_cluster_name));
112 	return len;
113 }
114 
115 CONFIGFS_ATTR(cluster_, cluster_name);
116 
117 static ssize_t cluster_tcp_port_show(struct config_item *item, char *buf)
118 {
119 	return sprintf(buf, "%u\n", be16_to_cpu(dlm_config.ci_tcp_port));
120 }
121 
122 static int dlm_check_zero_and_dlm_running(unsigned int x)
123 {
124 	if (!x)
125 		return -EINVAL;
126 
127 	if (dlm_lowcomms_is_running())
128 		return -EBUSY;
129 
130 	return 0;
131 }
132 
133 static ssize_t cluster_tcp_port_store(struct config_item *item,
134 				      const char *buf, size_t len)
135 {
136 	int rc;
137 	u16 x;
138 
139 	if (!capable(CAP_SYS_ADMIN))
140 		return -EPERM;
141 
142 	rc = kstrtou16(buf, 0, &x);
143 	if (rc)
144 		return rc;
145 
146 	rc = dlm_check_zero_and_dlm_running(x);
147 	if (rc)
148 		return rc;
149 
150 	dlm_config.ci_tcp_port = cpu_to_be16(x);
151 	return len;
152 }
153 
154 CONFIGFS_ATTR(cluster_, tcp_port);
155 
156 static ssize_t cluster_set(unsigned int *info_field,
157 			   int (*check_cb)(unsigned int x),
158 			   const char *buf, size_t len)
159 {
160 	unsigned int x;
161 	int rc;
162 
163 	if (!capable(CAP_SYS_ADMIN))
164 		return -EPERM;
165 	rc = kstrtouint(buf, 0, &x);
166 	if (rc)
167 		return rc;
168 
169 	if (check_cb) {
170 		rc = check_cb(x);
171 		if (rc)
172 			return rc;
173 	}
174 
175 	*info_field = x;
176 
177 	return len;
178 }
179 
180 #define CLUSTER_ATTR(name, check_cb)                                          \
181 static ssize_t cluster_##name##_store(struct config_item *item, \
182 		const char *buf, size_t len) \
183 {                                                                             \
184 	return cluster_set(&dlm_config.ci_##name, check_cb, buf, len);        \
185 }                                                                             \
186 static ssize_t cluster_##name##_show(struct config_item *item, char *buf)     \
187 {                                                                             \
188 	return snprintf(buf, PAGE_SIZE, "%u\n", dlm_config.ci_##name);        \
189 }                                                                             \
190 CONFIGFS_ATTR(cluster_, name);
191 
192 static int dlm_check_protocol_and_dlm_running(unsigned int x)
193 {
194 	switch (x) {
195 	case 0:
196 		/* TCP */
197 		break;
198 	case 1:
199 		/* SCTP */
200 		if (!IS_ENABLED(CONFIG_IP_SCTP))
201 			return -EOPNOTSUPP;
202 
203 		break;
204 	default:
205 		return -EINVAL;
206 	}
207 
208 	if (dlm_lowcomms_is_running())
209 		return -EBUSY;
210 
211 	return 0;
212 }
213 
214 static int dlm_check_zero(unsigned int x)
215 {
216 	if (!x)
217 		return -EINVAL;
218 
219 	return 0;
220 }
221 
222 static int dlm_check_buffer_size(unsigned int x)
223 {
224 	if (x < DLM_MAX_SOCKET_BUFSIZE)
225 		return -EINVAL;
226 
227 	return 0;
228 }
229 
230 CLUSTER_ATTR(buffer_size, dlm_check_buffer_size);
231 CLUSTER_ATTR(rsbtbl_size, dlm_check_zero);
232 CLUSTER_ATTR(recover_timer, dlm_check_zero);
233 CLUSTER_ATTR(toss_secs, dlm_check_zero);
234 CLUSTER_ATTR(scan_secs, dlm_check_zero);
235 CLUSTER_ATTR(log_debug, NULL);
236 CLUSTER_ATTR(log_info, NULL);
237 CLUSTER_ATTR(protocol, dlm_check_protocol_and_dlm_running);
238 CLUSTER_ATTR(mark, NULL);
239 CLUSTER_ATTR(new_rsb_count, NULL);
240 CLUSTER_ATTR(recover_callbacks, NULL);
241 
242 static struct configfs_attribute *cluster_attrs[] = {
243 	[CLUSTER_ATTR_TCP_PORT] = &cluster_attr_tcp_port,
244 	[CLUSTER_ATTR_BUFFER_SIZE] = &cluster_attr_buffer_size,
245 	[CLUSTER_ATTR_RSBTBL_SIZE] = &cluster_attr_rsbtbl_size,
246 	[CLUSTER_ATTR_RECOVER_TIMER] = &cluster_attr_recover_timer,
247 	[CLUSTER_ATTR_TOSS_SECS] = &cluster_attr_toss_secs,
248 	[CLUSTER_ATTR_SCAN_SECS] = &cluster_attr_scan_secs,
249 	[CLUSTER_ATTR_LOG_DEBUG] = &cluster_attr_log_debug,
250 	[CLUSTER_ATTR_LOG_INFO] = &cluster_attr_log_info,
251 	[CLUSTER_ATTR_PROTOCOL] = &cluster_attr_protocol,
252 	[CLUSTER_ATTR_MARK] = &cluster_attr_mark,
253 	[CLUSTER_ATTR_NEW_RSB_COUNT] = &cluster_attr_new_rsb_count,
254 	[CLUSTER_ATTR_RECOVER_CALLBACKS] = &cluster_attr_recover_callbacks,
255 	[CLUSTER_ATTR_CLUSTER_NAME] = &cluster_attr_cluster_name,
256 	NULL,
257 };
258 
259 enum {
260 	COMM_ATTR_NODEID = 0,
261 	COMM_ATTR_LOCAL,
262 	COMM_ATTR_ADDR,
263 	COMM_ATTR_ADDR_LIST,
264 	COMM_ATTR_MARK,
265 };
266 
267 enum {
268 	NODE_ATTR_NODEID = 0,
269 	NODE_ATTR_WEIGHT,
270 };
271 
272 struct dlm_clusters {
273 	struct configfs_subsystem subsys;
274 };
275 
276 struct dlm_spaces {
277 	struct config_group ss_group;
278 };
279 
280 struct dlm_space {
281 	struct config_group group;
282 	struct list_head members;
283 	struct mutex members_lock;
284 	int members_count;
285 	struct dlm_nodes *nds;
286 };
287 
288 struct dlm_comms {
289 	struct config_group cs_group;
290 };
291 
292 struct dlm_comm {
293 	struct config_item item;
294 	int seq;
295 	int nodeid;
296 	int local;
297 	int addr_count;
298 	unsigned int mark;
299 	struct sockaddr_storage *addr[DLM_MAX_ADDR_COUNT];
300 };
301 
302 struct dlm_nodes {
303 	struct config_group ns_group;
304 };
305 
306 struct dlm_node {
307 	struct config_item item;
308 	struct list_head list; /* space->members */
309 	int nodeid;
310 	int weight;
311 	int new;
312 	int comm_seq; /* copy of cm->seq when nd->nodeid is set */
313 };
314 
315 static struct configfs_group_operations clusters_ops = {
316 	.make_group = make_cluster,
317 	.drop_item = drop_cluster,
318 };
319 
320 static struct configfs_item_operations cluster_ops = {
321 	.release = release_cluster,
322 };
323 
324 static struct configfs_group_operations spaces_ops = {
325 	.make_group = make_space,
326 	.drop_item = drop_space,
327 };
328 
329 static struct configfs_item_operations space_ops = {
330 	.release = release_space,
331 };
332 
333 static struct configfs_group_operations comms_ops = {
334 	.make_item = make_comm,
335 	.drop_item = drop_comm,
336 };
337 
338 static struct configfs_item_operations comm_ops = {
339 	.release = release_comm,
340 };
341 
342 static struct configfs_group_operations nodes_ops = {
343 	.make_item = make_node,
344 	.drop_item = drop_node,
345 };
346 
347 static struct configfs_item_operations node_ops = {
348 	.release = release_node,
349 };
350 
351 static const struct config_item_type clusters_type = {
352 	.ct_group_ops = &clusters_ops,
353 	.ct_owner = THIS_MODULE,
354 };
355 
356 static const struct config_item_type cluster_type = {
357 	.ct_item_ops = &cluster_ops,
358 	.ct_attrs = cluster_attrs,
359 	.ct_owner = THIS_MODULE,
360 };
361 
362 static const struct config_item_type spaces_type = {
363 	.ct_group_ops = &spaces_ops,
364 	.ct_owner = THIS_MODULE,
365 };
366 
367 static const struct config_item_type space_type = {
368 	.ct_item_ops = &space_ops,
369 	.ct_owner = THIS_MODULE,
370 };
371 
372 static const struct config_item_type comms_type = {
373 	.ct_group_ops = &comms_ops,
374 	.ct_owner = THIS_MODULE,
375 };
376 
377 static const struct config_item_type comm_type = {
378 	.ct_item_ops = &comm_ops,
379 	.ct_attrs = comm_attrs,
380 	.ct_owner = THIS_MODULE,
381 };
382 
383 static const struct config_item_type nodes_type = {
384 	.ct_group_ops = &nodes_ops,
385 	.ct_owner = THIS_MODULE,
386 };
387 
388 static const struct config_item_type node_type = {
389 	.ct_item_ops = &node_ops,
390 	.ct_attrs = node_attrs,
391 	.ct_owner = THIS_MODULE,
392 };
393 
394 static struct dlm_space *config_item_to_space(struct config_item *i)
395 {
396 	return i ? container_of(to_config_group(i), struct dlm_space, group) :
397 		   NULL;
398 }
399 
400 static struct dlm_comm *config_item_to_comm(struct config_item *i)
401 {
402 	return i ? container_of(i, struct dlm_comm, item) : NULL;
403 }
404 
405 static struct dlm_node *config_item_to_node(struct config_item *i)
406 {
407 	return i ? container_of(i, struct dlm_node, item) : NULL;
408 }
409 
410 static struct config_group *make_cluster(struct config_group *g,
411 					 const char *name)
412 {
413 	struct dlm_cluster *cl = NULL;
414 	struct dlm_spaces *sps = NULL;
415 	struct dlm_comms *cms = NULL;
416 
417 	cl = kzalloc(sizeof(struct dlm_cluster), GFP_NOFS);
418 	sps = kzalloc(sizeof(struct dlm_spaces), GFP_NOFS);
419 	cms = kzalloc(sizeof(struct dlm_comms), GFP_NOFS);
420 
421 	if (!cl || !sps || !cms)
422 		goto fail;
423 
424 	cl->sps = sps;
425 	cl->cms = cms;
426 
427 	config_group_init_type_name(&cl->group, name, &cluster_type);
428 	config_group_init_type_name(&sps->ss_group, "spaces", &spaces_type);
429 	config_group_init_type_name(&cms->cs_group, "comms", &comms_type);
430 
431 	configfs_add_default_group(&sps->ss_group, &cl->group);
432 	configfs_add_default_group(&cms->cs_group, &cl->group);
433 
434 	space_list = &sps->ss_group;
435 	comm_list = &cms->cs_group;
436 	return &cl->group;
437 
438  fail:
439 	kfree(cl);
440 	kfree(sps);
441 	kfree(cms);
442 	return ERR_PTR(-ENOMEM);
443 }
444 
445 static void drop_cluster(struct config_group *g, struct config_item *i)
446 {
447 	struct dlm_cluster *cl = config_item_to_cluster(i);
448 
449 	configfs_remove_default_groups(&cl->group);
450 
451 	space_list = NULL;
452 	comm_list = NULL;
453 
454 	config_item_put(i);
455 }
456 
457 static void release_cluster(struct config_item *i)
458 {
459 	struct dlm_cluster *cl = config_item_to_cluster(i);
460 
461 	kfree(cl->sps);
462 	kfree(cl->cms);
463 	kfree(cl);
464 }
465 
466 static struct config_group *make_space(struct config_group *g, const char *name)
467 {
468 	struct dlm_space *sp = NULL;
469 	struct dlm_nodes *nds = NULL;
470 
471 	sp = kzalloc(sizeof(struct dlm_space), GFP_NOFS);
472 	nds = kzalloc(sizeof(struct dlm_nodes), GFP_NOFS);
473 
474 	if (!sp || !nds)
475 		goto fail;
476 
477 	config_group_init_type_name(&sp->group, name, &space_type);
478 
479 	config_group_init_type_name(&nds->ns_group, "nodes", &nodes_type);
480 	configfs_add_default_group(&nds->ns_group, &sp->group);
481 
482 	INIT_LIST_HEAD(&sp->members);
483 	mutex_init(&sp->members_lock);
484 	sp->members_count = 0;
485 	sp->nds = nds;
486 	return &sp->group;
487 
488  fail:
489 	kfree(sp);
490 	kfree(nds);
491 	return ERR_PTR(-ENOMEM);
492 }
493 
494 static void drop_space(struct config_group *g, struct config_item *i)
495 {
496 	struct dlm_space *sp = config_item_to_space(i);
497 
498 	/* assert list_empty(&sp->members) */
499 
500 	configfs_remove_default_groups(&sp->group);
501 	config_item_put(i);
502 }
503 
504 static void release_space(struct config_item *i)
505 {
506 	struct dlm_space *sp = config_item_to_space(i);
507 	kfree(sp->nds);
508 	kfree(sp);
509 }
510 
511 static struct config_item *make_comm(struct config_group *g, const char *name)
512 {
513 	struct dlm_comm *cm;
514 	unsigned int nodeid;
515 	int rv;
516 
517 	rv = kstrtouint(name, 0, &nodeid);
518 	if (rv)
519 		return ERR_PTR(rv);
520 
521 	cm = kzalloc(sizeof(struct dlm_comm), GFP_NOFS);
522 	if (!cm)
523 		return ERR_PTR(-ENOMEM);
524 
525 	config_item_init_type_name(&cm->item, name, &comm_type);
526 
527 	cm->seq = dlm_comm_count++;
528 	if (!cm->seq)
529 		cm->seq = dlm_comm_count++;
530 
531 	cm->nodeid = nodeid;
532 	cm->local = 0;
533 	cm->addr_count = 0;
534 	cm->mark = 0;
535 	return &cm->item;
536 }
537 
538 static void drop_comm(struct config_group *g, struct config_item *i)
539 {
540 	struct dlm_comm *cm = config_item_to_comm(i);
541 	if (local_comm == cm)
542 		local_comm = NULL;
543 	dlm_midcomms_close(cm->nodeid);
544 	while (cm->addr_count--)
545 		kfree(cm->addr[cm->addr_count]);
546 	config_item_put(i);
547 }
548 
549 static void release_comm(struct config_item *i)
550 {
551 	struct dlm_comm *cm = config_item_to_comm(i);
552 	kfree(cm);
553 }
554 
555 static struct config_item *make_node(struct config_group *g, const char *name)
556 {
557 	struct dlm_space *sp = config_item_to_space(g->cg_item.ci_parent);
558 	unsigned int nodeid;
559 	struct dlm_node *nd;
560 	uint32_t seq = 0;
561 	int rv;
562 
563 	rv = kstrtouint(name, 0, &nodeid);
564 	if (rv)
565 		return ERR_PTR(rv);
566 
567 	nd = kzalloc(sizeof(struct dlm_node), GFP_NOFS);
568 	if (!nd)
569 		return ERR_PTR(-ENOMEM);
570 
571 	config_item_init_type_name(&nd->item, name, &node_type);
572 	nd->nodeid = nodeid;
573 	nd->weight = 1;  /* default weight of 1 if none is set */
574 	nd->new = 1;     /* set to 0 once it's been read by dlm_nodeid_list() */
575 	dlm_comm_seq(nodeid, &seq, true);
576 	nd->comm_seq = seq;
577 
578 	mutex_lock(&sp->members_lock);
579 	list_add(&nd->list, &sp->members);
580 	sp->members_count++;
581 	mutex_unlock(&sp->members_lock);
582 
583 	return &nd->item;
584 }
585 
586 static void drop_node(struct config_group *g, struct config_item *i)
587 {
588 	struct dlm_space *sp = config_item_to_space(g->cg_item.ci_parent);
589 	struct dlm_node *nd = config_item_to_node(i);
590 
591 	mutex_lock(&sp->members_lock);
592 	list_del(&nd->list);
593 	sp->members_count--;
594 	mutex_unlock(&sp->members_lock);
595 
596 	config_item_put(i);
597 }
598 
599 static void release_node(struct config_item *i)
600 {
601 	struct dlm_node *nd = config_item_to_node(i);
602 	kfree(nd);
603 }
604 
605 static struct dlm_clusters clusters_root = {
606 	.subsys = {
607 		.su_group = {
608 			.cg_item = {
609 				.ci_namebuf = "dlm",
610 				.ci_type = &clusters_type,
611 			},
612 		},
613 	},
614 };
615 
616 int __init dlm_config_init(void)
617 {
618 	config_group_init(&clusters_root.subsys.su_group);
619 	mutex_init(&clusters_root.subsys.su_mutex);
620 	return configfs_register_subsystem(&clusters_root.subsys);
621 }
622 
623 void dlm_config_exit(void)
624 {
625 	configfs_unregister_subsystem(&clusters_root.subsys);
626 }
627 
628 /*
629  * Functions for user space to read/write attributes
630  */
631 
632 static ssize_t comm_nodeid_show(struct config_item *item, char *buf)
633 {
634 	unsigned int nodeid;
635 	int rv;
636 
637 	rv = kstrtouint(config_item_name(item), 0, &nodeid);
638 	if (WARN_ON(rv))
639 		return rv;
640 
641 	return sprintf(buf, "%u\n", nodeid);
642 }
643 
644 static ssize_t comm_nodeid_store(struct config_item *item, const char *buf,
645 				 size_t len)
646 {
647 	return len;
648 }
649 
650 static ssize_t comm_local_show(struct config_item *item, char *buf)
651 {
652 	return sprintf(buf, "%d\n", config_item_to_comm(item)->local);
653 }
654 
655 static ssize_t comm_local_store(struct config_item *item, const char *buf,
656 				size_t len)
657 {
658 	struct dlm_comm *cm = config_item_to_comm(item);
659 	int rc = kstrtoint(buf, 0, &cm->local);
660 
661 	if (rc)
662 		return rc;
663 	if (cm->local && !local_comm)
664 		local_comm = cm;
665 	return len;
666 }
667 
668 static ssize_t comm_addr_store(struct config_item *item, const char *buf,
669 		size_t len)
670 {
671 	struct dlm_comm *cm = config_item_to_comm(item);
672 	struct sockaddr_storage *addr;
673 	int rv;
674 
675 	if (len != sizeof(struct sockaddr_storage))
676 		return -EINVAL;
677 
678 	if (cm->addr_count >= DLM_MAX_ADDR_COUNT)
679 		return -ENOSPC;
680 
681 	addr = kzalloc(sizeof(*addr), GFP_NOFS);
682 	if (!addr)
683 		return -ENOMEM;
684 
685 	memcpy(addr, buf, len);
686 
687 	rv = dlm_midcomms_addr(cm->nodeid, addr);
688 	if (rv) {
689 		kfree(addr);
690 		return rv;
691 	}
692 
693 	cm->addr[cm->addr_count++] = addr;
694 	return len;
695 }
696 
697 static ssize_t comm_addr_list_show(struct config_item *item, char *buf)
698 {
699 	struct dlm_comm *cm = config_item_to_comm(item);
700 	ssize_t s;
701 	ssize_t allowance;
702 	int i;
703 	struct sockaddr_storage *addr;
704 	struct sockaddr_in *addr_in;
705 	struct sockaddr_in6 *addr_in6;
706 
707 	/* Taken from ip6_addr_string() defined in lib/vsprintf.c */
708 	char buf0[sizeof("AF_INET6	xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255\n")];
709 
710 
711 	/* Derived from SIMPLE_ATTR_SIZE of fs/configfs/file.c */
712 	allowance = 4096;
713 	buf[0] = '\0';
714 
715 	for (i = 0; i < cm->addr_count; i++) {
716 		addr = cm->addr[i];
717 
718 		switch(addr->ss_family) {
719 		case AF_INET:
720 			addr_in = (struct sockaddr_in *)addr;
721 			s = sprintf(buf0, "AF_INET	%pI4\n", &addr_in->sin_addr.s_addr);
722 			break;
723 		case AF_INET6:
724 			addr_in6 = (struct sockaddr_in6 *)addr;
725 			s = sprintf(buf0, "AF_INET6	%pI6\n", &addr_in6->sin6_addr);
726 			break;
727 		default:
728 			s = sprintf(buf0, "%s\n", "<UNKNOWN>");
729 			break;
730 		}
731 		allowance -= s;
732 		if (allowance >= 0)
733 			strcat(buf, buf0);
734 		else {
735 			allowance += s;
736 			break;
737 		}
738 	}
739 	return 4096 - allowance;
740 }
741 
742 static ssize_t comm_mark_show(struct config_item *item, char *buf)
743 {
744 	return sprintf(buf, "%u\n", config_item_to_comm(item)->mark);
745 }
746 
747 static ssize_t comm_mark_store(struct config_item *item, const char *buf,
748 			       size_t len)
749 {
750 	struct dlm_comm *comm;
751 	unsigned int mark;
752 	int rc;
753 
754 	rc = kstrtouint(buf, 0, &mark);
755 	if (rc)
756 		return rc;
757 
758 	if (mark == 0)
759 		mark = dlm_config.ci_mark;
760 
761 	comm = config_item_to_comm(item);
762 	rc = dlm_lowcomms_nodes_set_mark(comm->nodeid, mark);
763 	if (rc)
764 		return rc;
765 
766 	comm->mark = mark;
767 	return len;
768 }
769 
770 CONFIGFS_ATTR(comm_, nodeid);
771 CONFIGFS_ATTR(comm_, local);
772 CONFIGFS_ATTR(comm_, mark);
773 CONFIGFS_ATTR_WO(comm_, addr);
774 CONFIGFS_ATTR_RO(comm_, addr_list);
775 
776 static struct configfs_attribute *comm_attrs[] = {
777 	[COMM_ATTR_NODEID] = &comm_attr_nodeid,
778 	[COMM_ATTR_LOCAL] = &comm_attr_local,
779 	[COMM_ATTR_ADDR] = &comm_attr_addr,
780 	[COMM_ATTR_ADDR_LIST] = &comm_attr_addr_list,
781 	[COMM_ATTR_MARK] = &comm_attr_mark,
782 	NULL,
783 };
784 
785 static ssize_t node_nodeid_show(struct config_item *item, char *buf)
786 {
787 	unsigned int nodeid;
788 	int rv;
789 
790 	rv = kstrtouint(config_item_name(item), 0, &nodeid);
791 	if (WARN_ON(rv))
792 		return rv;
793 
794 	return sprintf(buf, "%u\n", nodeid);
795 }
796 
797 static ssize_t node_nodeid_store(struct config_item *item, const char *buf,
798 				 size_t len)
799 {
800 	return len;
801 }
802 
803 static ssize_t node_weight_show(struct config_item *item, char *buf)
804 {
805 	return sprintf(buf, "%d\n", config_item_to_node(item)->weight);
806 }
807 
808 static ssize_t node_weight_store(struct config_item *item, const char *buf,
809 				 size_t len)
810 {
811 	int rc = kstrtoint(buf, 0, &config_item_to_node(item)->weight);
812 
813 	if (rc)
814 		return rc;
815 	return len;
816 }
817 
818 CONFIGFS_ATTR(node_, nodeid);
819 CONFIGFS_ATTR(node_, weight);
820 
821 static struct configfs_attribute *node_attrs[] = {
822 	[NODE_ATTR_NODEID] = &node_attr_nodeid,
823 	[NODE_ATTR_WEIGHT] = &node_attr_weight,
824 	NULL,
825 };
826 
827 /*
828  * Functions for the dlm to get the info that's been configured
829  */
830 
831 static struct dlm_space *get_space(char *name)
832 {
833 	struct config_item *i;
834 
835 	if (!space_list)
836 		return NULL;
837 
838 	mutex_lock(&space_list->cg_subsys->su_mutex);
839 	i = config_group_find_item(space_list, name);
840 	mutex_unlock(&space_list->cg_subsys->su_mutex);
841 
842 	return config_item_to_space(i);
843 }
844 
845 static void put_space(struct dlm_space *sp)
846 {
847 	config_item_put(&sp->group.cg_item);
848 }
849 
850 static struct dlm_comm *get_comm(int nodeid)
851 {
852 	struct config_item *i;
853 	struct dlm_comm *cm = NULL;
854 	int found = 0;
855 
856 	if (!comm_list)
857 		return NULL;
858 
859 	WARN_ON_ONCE(!mutex_is_locked(&clusters_root.subsys.su_mutex));
860 
861 	list_for_each_entry(i, &comm_list->cg_children, ci_entry) {
862 		cm = config_item_to_comm(i);
863 
864 		if (cm->nodeid != nodeid)
865 			continue;
866 		found = 1;
867 		config_item_get(i);
868 		break;
869 	}
870 
871 	if (!found)
872 		cm = NULL;
873 	return cm;
874 }
875 
876 static void put_comm(struct dlm_comm *cm)
877 {
878 	config_item_put(&cm->item);
879 }
880 
881 /* caller must free mem */
882 int dlm_config_nodes(char *lsname, struct dlm_config_node **nodes_out,
883 		     int *count_out)
884 {
885 	struct dlm_space *sp;
886 	struct dlm_node *nd;
887 	struct dlm_config_node *nodes, *node;
888 	int rv, count;
889 
890 	sp = get_space(lsname);
891 	if (!sp)
892 		return -EEXIST;
893 
894 	mutex_lock(&sp->members_lock);
895 	if (!sp->members_count) {
896 		rv = -EINVAL;
897 		printk(KERN_ERR "dlm: zero members_count\n");
898 		goto out;
899 	}
900 
901 	count = sp->members_count;
902 
903 	nodes = kcalloc(count, sizeof(struct dlm_config_node), GFP_NOFS);
904 	if (!nodes) {
905 		rv = -ENOMEM;
906 		goto out;
907 	}
908 
909 	node = nodes;
910 	list_for_each_entry(nd, &sp->members, list) {
911 		node->nodeid = nd->nodeid;
912 		node->weight = nd->weight;
913 		node->new = nd->new;
914 		node->comm_seq = nd->comm_seq;
915 		node++;
916 
917 		nd->new = 0;
918 	}
919 
920 	*count_out = count;
921 	*nodes_out = nodes;
922 	rv = 0;
923  out:
924 	mutex_unlock(&sp->members_lock);
925 	put_space(sp);
926 	return rv;
927 }
928 
929 int dlm_comm_seq(int nodeid, uint32_t *seq, bool locked)
930 {
931 	struct dlm_comm *cm;
932 
933 	if (locked) {
934 		cm = get_comm(nodeid);
935 	} else {
936 		mutex_lock(&clusters_root.subsys.su_mutex);
937 		cm = get_comm(nodeid);
938 		mutex_unlock(&clusters_root.subsys.su_mutex);
939 	}
940 	if (!cm)
941 		return -ENOENT;
942 
943 	*seq = cm->seq;
944 	put_comm(cm);
945 	return 0;
946 }
947 
948 int dlm_our_nodeid(void)
949 {
950 	return local_comm->nodeid;
951 }
952 
953 /* num 0 is first addr, num 1 is second addr */
954 int dlm_our_addr(struct sockaddr_storage *addr, int num)
955 {
956 	if (!local_comm)
957 		return -1;
958 	if (num + 1 > local_comm->addr_count)
959 		return -1;
960 	memcpy(addr, local_comm->addr[num], sizeof(*addr));
961 	return 0;
962 }
963 
964 /* Config file defaults */
965 #define DEFAULT_TCP_PORT       21064
966 #define DEFAULT_RSBTBL_SIZE     1024
967 #define DEFAULT_RECOVER_TIMER      5
968 #define DEFAULT_TOSS_SECS         10
969 #define DEFAULT_SCAN_SECS          5
970 #define DEFAULT_LOG_DEBUG          0
971 #define DEFAULT_LOG_INFO           1
972 #define DEFAULT_PROTOCOL           DLM_PROTO_TCP
973 #define DEFAULT_MARK               0
974 #define DEFAULT_NEW_RSB_COUNT    128
975 #define DEFAULT_RECOVER_CALLBACKS  0
976 #define DEFAULT_CLUSTER_NAME      ""
977 
978 struct dlm_config_info dlm_config = {
979 	.ci_tcp_port = cpu_to_be16(DEFAULT_TCP_PORT),
980 	.ci_buffer_size = DLM_MAX_SOCKET_BUFSIZE,
981 	.ci_rsbtbl_size = DEFAULT_RSBTBL_SIZE,
982 	.ci_recover_timer = DEFAULT_RECOVER_TIMER,
983 	.ci_toss_secs = DEFAULT_TOSS_SECS,
984 	.ci_scan_secs = DEFAULT_SCAN_SECS,
985 	.ci_log_debug = DEFAULT_LOG_DEBUG,
986 	.ci_log_info = DEFAULT_LOG_INFO,
987 	.ci_protocol = DEFAULT_PROTOCOL,
988 	.ci_mark = DEFAULT_MARK,
989 	.ci_new_rsb_count = DEFAULT_NEW_RSB_COUNT,
990 	.ci_recover_callbacks = DEFAULT_RECOVER_CALLBACKS,
991 	.ci_cluster_name = DEFAULT_CLUSTER_NAME
992 };
993 
994