[DLM] add lock timeouts and warnings [2/6]
[linux-2.6.git] / fs / dlm / config.c
1 /******************************************************************************
2 *******************************************************************************
3 **
4 **  Copyright (C) Sistina Software, Inc.  1997-2003  All rights reserved.
5 **  Copyright (C) 2004-2007 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         unsigned int cl_protocol;
93         unsigned int cl_timewarn_cs;
94 };
95
96 enum {
97         CLUSTER_ATTR_TCP_PORT = 0,
98         CLUSTER_ATTR_BUFFER_SIZE,
99         CLUSTER_ATTR_RSBTBL_SIZE,
100         CLUSTER_ATTR_LKBTBL_SIZE,
101         CLUSTER_ATTR_DIRTBL_SIZE,
102         CLUSTER_ATTR_RECOVER_TIMER,
103         CLUSTER_ATTR_TOSS_SECS,
104         CLUSTER_ATTR_SCAN_SECS,
105         CLUSTER_ATTR_LOG_DEBUG,
106         CLUSTER_ATTR_PROTOCOL,
107         CLUSTER_ATTR_TIMEWARN_CS,
108 };
109
110 struct cluster_attribute {
111         struct configfs_attribute attr;
112         ssize_t (*show)(struct cluster *, char *);
113         ssize_t (*store)(struct cluster *, const char *, size_t);
114 };
115
116 static ssize_t cluster_set(struct cluster *cl, unsigned int *cl_field,
117                            unsigned int *info_field, int check_zero,
118                            const char *buf, size_t len)
119 {
120         unsigned int x;
121
122         if (!capable(CAP_SYS_ADMIN))
123                 return -EACCES;
124
125         x = simple_strtoul(buf, NULL, 0);
126
127         if (check_zero && !x)
128                 return -EINVAL;
129
130         *cl_field = x;
131         *info_field = x;
132
133         return len;
134 }
135
136 #define __CONFIGFS_ATTR(_name,_mode,_read,_write) {                           \
137         .attr   = { .ca_name = __stringify(_name),                            \
138                     .ca_mode = _mode,                                         \
139                     .ca_owner = THIS_MODULE },                                \
140         .show   = _read,                                                      \
141         .store  = _write,                                                     \
142 }
143
144 #define CLUSTER_ATTR(name, check_zero)                                        \
145 static ssize_t name##_write(struct cluster *cl, const char *buf, size_t len)  \
146 {                                                                             \
147         return cluster_set(cl, &cl->cl_##name, &dlm_config.ci_##name,         \
148                            check_zero, buf, len);                             \
149 }                                                                             \
150 static ssize_t name##_read(struct cluster *cl, char *buf)                     \
151 {                                                                             \
152         return snprintf(buf, PAGE_SIZE, "%u\n", cl->cl_##name);               \
153 }                                                                             \
154 static struct cluster_attribute cluster_attr_##name =                         \
155 __CONFIGFS_ATTR(name, 0644, name##_read, name##_write)
156
157 CLUSTER_ATTR(tcp_port, 1);
158 CLUSTER_ATTR(buffer_size, 1);
159 CLUSTER_ATTR(rsbtbl_size, 1);
160 CLUSTER_ATTR(lkbtbl_size, 1);
161 CLUSTER_ATTR(dirtbl_size, 1);
162 CLUSTER_ATTR(recover_timer, 1);
163 CLUSTER_ATTR(toss_secs, 1);
164 CLUSTER_ATTR(scan_secs, 1);
165 CLUSTER_ATTR(log_debug, 0);
166 CLUSTER_ATTR(protocol, 0);
167 CLUSTER_ATTR(timewarn_cs, 1);
168
169 static struct configfs_attribute *cluster_attrs[] = {
170         [CLUSTER_ATTR_TCP_PORT] = &cluster_attr_tcp_port.attr,
171         [CLUSTER_ATTR_BUFFER_SIZE] = &cluster_attr_buffer_size.attr,
172         [CLUSTER_ATTR_RSBTBL_SIZE] = &cluster_attr_rsbtbl_size.attr,
173         [CLUSTER_ATTR_LKBTBL_SIZE] = &cluster_attr_lkbtbl_size.attr,
174         [CLUSTER_ATTR_DIRTBL_SIZE] = &cluster_attr_dirtbl_size.attr,
175         [CLUSTER_ATTR_RECOVER_TIMER] = &cluster_attr_recover_timer.attr,
176         [CLUSTER_ATTR_TOSS_SECS] = &cluster_attr_toss_secs.attr,
177         [CLUSTER_ATTR_SCAN_SECS] = &cluster_attr_scan_secs.attr,
178         [CLUSTER_ATTR_LOG_DEBUG] = &cluster_attr_log_debug.attr,
179         [CLUSTER_ATTR_PROTOCOL] = &cluster_attr_protocol.attr,
180         [CLUSTER_ATTR_TIMEWARN_CS] = &cluster_attr_timewarn_cs.attr,
181         NULL,
182 };
183
184 enum {
185         COMM_ATTR_NODEID = 0,
186         COMM_ATTR_LOCAL,
187         COMM_ATTR_ADDR,
188 };
189
190 struct comm_attribute {
191         struct configfs_attribute attr;
192         ssize_t (*show)(struct comm *, char *);
193         ssize_t (*store)(struct comm *, const char *, size_t);
194 };
195
196 static struct comm_attribute comm_attr_nodeid = {
197         .attr   = { .ca_owner = THIS_MODULE,
198                     .ca_name = "nodeid",
199                     .ca_mode = S_IRUGO | S_IWUSR },
200         .show   = comm_nodeid_read,
201         .store  = comm_nodeid_write,
202 };
203
204 static struct comm_attribute comm_attr_local = {
205         .attr   = { .ca_owner = THIS_MODULE,
206                     .ca_name = "local",
207                     .ca_mode = S_IRUGO | S_IWUSR },
208         .show   = comm_local_read,
209         .store  = comm_local_write,
210 };
211
212 static struct comm_attribute comm_attr_addr = {
213         .attr   = { .ca_owner = THIS_MODULE,
214                     .ca_name = "addr",
215                     .ca_mode = S_IRUGO | S_IWUSR },
216         .store  = comm_addr_write,
217 };
218
219 static struct configfs_attribute *comm_attrs[] = {
220         [COMM_ATTR_NODEID] = &comm_attr_nodeid.attr,
221         [COMM_ATTR_LOCAL] = &comm_attr_local.attr,
222         [COMM_ATTR_ADDR] = &comm_attr_addr.attr,
223         NULL,
224 };
225
226 enum {
227         NODE_ATTR_NODEID = 0,
228         NODE_ATTR_WEIGHT,
229 };
230
231 struct node_attribute {
232         struct configfs_attribute attr;
233         ssize_t (*show)(struct node *, char *);
234         ssize_t (*store)(struct node *, const char *, size_t);
235 };
236
237 static struct node_attribute node_attr_nodeid = {
238         .attr   = { .ca_owner = THIS_MODULE,
239                     .ca_name = "nodeid",
240                     .ca_mode = S_IRUGO | S_IWUSR },
241         .show   = node_nodeid_read,
242         .store  = node_nodeid_write,
243 };
244
245 static struct node_attribute node_attr_weight = {
246         .attr   = { .ca_owner = THIS_MODULE,
247                     .ca_name = "weight",
248                     .ca_mode = S_IRUGO | S_IWUSR },
249         .show   = node_weight_read,
250         .store  = node_weight_write,
251 };
252
253 static struct configfs_attribute *node_attrs[] = {
254         [NODE_ATTR_NODEID] = &node_attr_nodeid.attr,
255         [NODE_ATTR_WEIGHT] = &node_attr_weight.attr,
256         NULL,
257 };
258
259 struct clusters {
260         struct configfs_subsystem subsys;
261 };
262
263 struct spaces {
264         struct config_group ss_group;
265 };
266
267 struct space {
268         struct config_group group;
269         struct list_head members;
270         struct mutex members_lock;
271         int members_count;
272 };
273
274 struct comms {
275         struct config_group cs_group;
276 };
277
278 struct comm {
279         struct config_item item;
280         int nodeid;
281         int local;
282         int addr_count;
283         struct sockaddr_storage *addr[DLM_MAX_ADDR_COUNT];
284 };
285
286 struct nodes {
287         struct config_group ns_group;
288 };
289
290 struct node {
291         struct config_item item;
292         struct list_head list; /* space->members */
293         int nodeid;
294         int weight;
295 };
296
297 static struct configfs_group_operations clusters_ops = {
298         .make_group = make_cluster,
299         .drop_item = drop_cluster,
300 };
301
302 static struct configfs_item_operations cluster_ops = {
303         .release = release_cluster,
304         .show_attribute = show_cluster,
305         .store_attribute = store_cluster,
306 };
307
308 static struct configfs_group_operations spaces_ops = {
309         .make_group = make_space,
310         .drop_item = drop_space,
311 };
312
313 static struct configfs_item_operations space_ops = {
314         .release = release_space,
315 };
316
317 static struct configfs_group_operations comms_ops = {
318         .make_item = make_comm,
319         .drop_item = drop_comm,
320 };
321
322 static struct configfs_item_operations comm_ops = {
323         .release = release_comm,
324         .show_attribute = show_comm,
325         .store_attribute = store_comm,
326 };
327
328 static struct configfs_group_operations nodes_ops = {
329         .make_item = make_node,
330         .drop_item = drop_node,
331 };
332
333 static struct configfs_item_operations node_ops = {
334         .release = release_node,
335         .show_attribute = show_node,
336         .store_attribute = store_node,
337 };
338
339 static struct config_item_type clusters_type = {
340         .ct_group_ops = &clusters_ops,
341         .ct_owner = THIS_MODULE,
342 };
343
344 static struct config_item_type cluster_type = {
345         .ct_item_ops = &cluster_ops,
346         .ct_attrs = cluster_attrs,
347         .ct_owner = THIS_MODULE,
348 };
349
350 static struct config_item_type spaces_type = {
351         .ct_group_ops = &spaces_ops,
352         .ct_owner = THIS_MODULE,
353 };
354
355 static struct config_item_type space_type = {
356         .ct_item_ops = &space_ops,
357         .ct_owner = THIS_MODULE,
358 };
359
360 static struct config_item_type comms_type = {
361         .ct_group_ops = &comms_ops,
362         .ct_owner = THIS_MODULE,
363 };
364
365 static struct config_item_type comm_type = {
366         .ct_item_ops = &comm_ops,
367         .ct_attrs = comm_attrs,
368         .ct_owner = THIS_MODULE,
369 };
370
371 static struct config_item_type nodes_type = {
372         .ct_group_ops = &nodes_ops,
373         .ct_owner = THIS_MODULE,
374 };
375
376 static struct config_item_type node_type = {
377         .ct_item_ops = &node_ops,
378         .ct_attrs = node_attrs,
379         .ct_owner = THIS_MODULE,
380 };
381
382 static struct cluster *to_cluster(struct config_item *i)
383 {
384         return i ? container_of(to_config_group(i), struct cluster, group):NULL;
385 }
386
387 static struct space *to_space(struct config_item *i)
388 {
389         return i ? container_of(to_config_group(i), struct space, group) : NULL;
390 }
391
392 static struct comm *to_comm(struct config_item *i)
393 {
394         return i ? container_of(i, struct comm, item) : NULL;
395 }
396
397 static struct node *to_node(struct config_item *i)
398 {
399         return i ? container_of(i, struct node, item) : NULL;
400 }
401
402 static struct config_group *make_cluster(struct config_group *g,
403                                          const char *name)
404 {
405         struct cluster *cl = NULL;
406         struct spaces *sps = NULL;
407         struct comms *cms = NULL;
408         void *gps = NULL;
409
410         cl = kzalloc(sizeof(struct cluster), GFP_KERNEL);
411         gps = kcalloc(3, sizeof(struct config_group *), GFP_KERNEL);
412         sps = kzalloc(sizeof(struct spaces), GFP_KERNEL);
413         cms = kzalloc(sizeof(struct comms), GFP_KERNEL);
414
415         if (!cl || !gps || !sps || !cms)
416                 goto fail;
417
418         config_group_init_type_name(&cl->group, name, &cluster_type);
419         config_group_init_type_name(&sps->ss_group, "spaces", &spaces_type);
420         config_group_init_type_name(&cms->cs_group, "comms", &comms_type);
421
422         cl->group.default_groups = gps;
423         cl->group.default_groups[0] = &sps->ss_group;
424         cl->group.default_groups[1] = &cms->cs_group;
425         cl->group.default_groups[2] = NULL;
426
427         cl->cl_tcp_port = dlm_config.ci_tcp_port;
428         cl->cl_buffer_size = dlm_config.ci_buffer_size;
429         cl->cl_rsbtbl_size = dlm_config.ci_rsbtbl_size;
430         cl->cl_lkbtbl_size = dlm_config.ci_lkbtbl_size;
431         cl->cl_dirtbl_size = dlm_config.ci_dirtbl_size;
432         cl->cl_recover_timer = dlm_config.ci_recover_timer;
433         cl->cl_toss_secs = dlm_config.ci_toss_secs;
434         cl->cl_scan_secs = dlm_config.ci_scan_secs;
435         cl->cl_log_debug = dlm_config.ci_log_debug;
436
437         space_list = &sps->ss_group;
438         comm_list = &cms->cs_group;
439         return &cl->group;
440
441  fail:
442         kfree(cl);
443         kfree(gps);
444         kfree(sps);
445         kfree(cms);
446         return NULL;
447 }
448
449 static void drop_cluster(struct config_group *g, struct config_item *i)
450 {
451         struct cluster *cl = to_cluster(i);
452         struct config_item *tmp;
453         int j;
454
455         for (j = 0; cl->group.default_groups[j]; j++) {
456                 tmp = &cl->group.default_groups[j]->cg_item;
457                 cl->group.default_groups[j] = NULL;
458                 config_item_put(tmp);
459         }
460
461         space_list = NULL;
462         comm_list = NULL;
463
464         config_item_put(i);
465 }
466
467 static void release_cluster(struct config_item *i)
468 {
469         struct cluster *cl = to_cluster(i);
470         kfree(cl->group.default_groups);
471         kfree(cl);
472 }
473
474 static struct config_group *make_space(struct config_group *g, const char *name)
475 {
476         struct space *sp = NULL;
477         struct nodes *nds = NULL;
478         void *gps = NULL;
479
480         sp = kzalloc(sizeof(struct space), GFP_KERNEL);
481         gps = kcalloc(2, sizeof(struct config_group *), GFP_KERNEL);
482         nds = kzalloc(sizeof(struct nodes), GFP_KERNEL);
483
484         if (!sp || !gps || !nds)
485                 goto fail;
486
487         config_group_init_type_name(&sp->group, name, &space_type);
488         config_group_init_type_name(&nds->ns_group, "nodes", &nodes_type);
489
490         sp->group.default_groups = gps;
491         sp->group.default_groups[0] = &nds->ns_group;
492         sp->group.default_groups[1] = NULL;
493
494         INIT_LIST_HEAD(&sp->members);
495         mutex_init(&sp->members_lock);
496         sp->members_count = 0;
497         return &sp->group;
498
499  fail:
500         kfree(sp);
501         kfree(gps);
502         kfree(nds);
503         return NULL;
504 }
505
506 static void drop_space(struct config_group *g, struct config_item *i)
507 {
508         struct space *sp = to_space(i);
509         struct config_item *tmp;
510         int j;
511
512         /* assert list_empty(&sp->members) */
513
514         for (j = 0; sp->group.default_groups[j]; j++) {
515                 tmp = &sp->group.default_groups[j]->cg_item;
516                 sp->group.default_groups[j] = NULL;
517                 config_item_put(tmp);
518         }
519
520         config_item_put(i);
521 }
522
523 static void release_space(struct config_item *i)
524 {
525         struct space *sp = to_space(i);
526         kfree(sp->group.default_groups);
527         kfree(sp);
528 }
529
530 static struct config_item *make_comm(struct config_group *g, const char *name)
531 {
532         struct comm *cm;
533
534         cm = kzalloc(sizeof(struct comm), GFP_KERNEL);
535         if (!cm)
536                 return NULL;
537
538         config_item_init_type_name(&cm->item, name, &comm_type);
539         cm->nodeid = -1;
540         cm->local = 0;
541         cm->addr_count = 0;
542         return &cm->item;
543 }
544
545 static void drop_comm(struct config_group *g, struct config_item *i)
546 {
547         struct comm *cm = to_comm(i);
548         if (local_comm == cm)
549                 local_comm = NULL;
550         dlm_lowcomms_close(cm->nodeid);
551         while (cm->addr_count--)
552                 kfree(cm->addr[cm->addr_count]);
553         config_item_put(i);
554 }
555
556 static void release_comm(struct config_item *i)
557 {
558         struct comm *cm = to_comm(i);
559         kfree(cm);
560 }
561
562 static struct config_item *make_node(struct config_group *g, const char *name)
563 {
564         struct space *sp = to_space(g->cg_item.ci_parent);
565         struct node *nd;
566
567         nd = kzalloc(sizeof(struct node), GFP_KERNEL);
568         if (!nd)
569                 return NULL;
570
571         config_item_init_type_name(&nd->item, name, &node_type);
572         nd->nodeid = -1;
573         nd->weight = 1;  /* default weight of 1 if none is set */
574
575         mutex_lock(&sp->members_lock);
576         list_add(&nd->list, &sp->members);
577         sp->members_count++;
578         mutex_unlock(&sp->members_lock);
579
580         return &nd->item;
581 }
582
583 static void drop_node(struct config_group *g, struct config_item *i)
584 {
585         struct space *sp = to_space(g->cg_item.ci_parent);
586         struct node *nd = to_node(i);
587
588         mutex_lock(&sp->members_lock);
589         list_del(&nd->list);
590         sp->members_count--;
591         mutex_unlock(&sp->members_lock);
592
593         config_item_put(i);
594 }
595
596 static void release_node(struct config_item *i)
597 {
598         struct node *nd = to_node(i);
599         kfree(nd);
600 }
601
602 static struct clusters clusters_root = {
603         .subsys = {
604                 .su_group = {
605                         .cg_item = {
606                                 .ci_namebuf = "dlm",
607                                 .ci_type = &clusters_type,
608                         },
609                 },
610         },
611 };
612
613 int dlm_config_init(void)
614 {
615         config_group_init(&clusters_root.subsys.su_group);
616         init_MUTEX(&clusters_root.subsys.su_sem);
617         return configfs_register_subsystem(&clusters_root.subsys);
618 }
619
620 void dlm_config_exit(void)
621 {
622         configfs_unregister_subsystem(&clusters_root.subsys);
623 }
624
625 /*
626  * Functions for user space to read/write attributes
627  */
628
629 static ssize_t show_cluster(struct config_item *i, struct configfs_attribute *a,
630                             char *buf)
631 {
632         struct cluster *cl = to_cluster(i);
633         struct cluster_attribute *cla =
634                         container_of(a, struct cluster_attribute, attr);
635         return cla->show ? cla->show(cl, buf) : 0;
636 }
637
638 static ssize_t store_cluster(struct config_item *i,
639                              struct configfs_attribute *a,
640                              const char *buf, size_t len)
641 {
642         struct cluster *cl = to_cluster(i);
643         struct cluster_attribute *cla =
644                 container_of(a, struct cluster_attribute, attr);
645         return cla->store ? cla->store(cl, buf, len) : -EINVAL;
646 }
647
648 static ssize_t show_comm(struct config_item *i, struct configfs_attribute *a,
649                          char *buf)
650 {
651         struct comm *cm = to_comm(i);
652         struct comm_attribute *cma =
653                         container_of(a, struct comm_attribute, attr);
654         return cma->show ? cma->show(cm, buf) : 0;
655 }
656
657 static ssize_t store_comm(struct config_item *i, struct configfs_attribute *a,
658                           const char *buf, size_t len)
659 {
660         struct comm *cm = to_comm(i);
661         struct comm_attribute *cma =
662                 container_of(a, struct comm_attribute, attr);
663         return cma->store ? cma->store(cm, buf, len) : -EINVAL;
664 }
665
666 static ssize_t comm_nodeid_read(struct comm *cm, char *buf)
667 {
668         return sprintf(buf, "%d\n", cm->nodeid);
669 }
670
671 static ssize_t comm_nodeid_write(struct comm *cm, const char *buf, size_t len)
672 {
673         cm->nodeid = simple_strtol(buf, NULL, 0);
674         return len;
675 }
676
677 static ssize_t comm_local_read(struct comm *cm, char *buf)
678 {
679         return sprintf(buf, "%d\n", cm->local);
680 }
681
682 static ssize_t comm_local_write(struct comm *cm, const char *buf, size_t len)
683 {
684         cm->local= simple_strtol(buf, NULL, 0);
685         if (cm->local && !local_comm)
686                 local_comm = cm;
687         return len;
688 }
689
690 static ssize_t comm_addr_write(struct comm *cm, const char *buf, size_t len)
691 {
692         struct sockaddr_storage *addr;
693
694         if (len != sizeof(struct sockaddr_storage))
695                 return -EINVAL;
696
697         if (cm->addr_count >= DLM_MAX_ADDR_COUNT)
698                 return -ENOSPC;
699
700         addr = kzalloc(sizeof(*addr), GFP_KERNEL);
701         if (!addr)
702                 return -ENOMEM;
703
704         memcpy(addr, buf, len);
705         cm->addr[cm->addr_count++] = addr;
706         return len;
707 }
708
709 static ssize_t show_node(struct config_item *i, struct configfs_attribute *a,
710                          char *buf)
711 {
712         struct node *nd = to_node(i);
713         struct node_attribute *nda =
714                         container_of(a, struct node_attribute, attr);
715         return nda->show ? nda->show(nd, buf) : 0;
716 }
717
718 static ssize_t store_node(struct config_item *i, struct configfs_attribute *a,
719                           const char *buf, size_t len)
720 {
721         struct node *nd = to_node(i);
722         struct node_attribute *nda =
723                 container_of(a, struct node_attribute, attr);
724         return nda->store ? nda->store(nd, buf, len) : -EINVAL;
725 }
726
727 static ssize_t node_nodeid_read(struct node *nd, char *buf)
728 {
729         return sprintf(buf, "%d\n", nd->nodeid);
730 }
731
732 static ssize_t node_nodeid_write(struct node *nd, const char *buf, size_t len)
733 {
734         nd->nodeid = simple_strtol(buf, NULL, 0);
735         return len;
736 }
737
738 static ssize_t node_weight_read(struct node *nd, char *buf)
739 {
740         return sprintf(buf, "%d\n", nd->weight);
741 }
742
743 static ssize_t node_weight_write(struct node *nd, const char *buf, size_t len)
744 {
745         nd->weight = simple_strtol(buf, NULL, 0);
746         return len;
747 }
748
749 /*
750  * Functions for the dlm to get the info that's been configured
751  */
752
753 static struct space *get_space(char *name)
754 {
755         struct config_item *i;
756
757         if (!space_list)
758                 return NULL;
759
760         down(&space_list->cg_subsys->su_sem);
761         i = config_group_find_obj(space_list, name);
762         up(&space_list->cg_subsys->su_sem);
763
764         return to_space(i);
765 }
766
767 static void put_space(struct space *sp)
768 {
769         config_item_put(&sp->group.cg_item);
770 }
771
772 static struct comm *get_comm(int nodeid, struct sockaddr_storage *addr)
773 {
774         struct config_item *i;
775         struct comm *cm = NULL;
776         int found = 0;
777
778         if (!comm_list)
779                 return NULL;
780
781         down(&clusters_root.subsys.su_sem);
782
783         list_for_each_entry(i, &comm_list->cg_children, ci_entry) {
784                 cm = to_comm(i);
785
786                 if (nodeid) {
787                         if (cm->nodeid != nodeid)
788                                 continue;
789                         found = 1;
790                         config_item_get(i);
791                         break;
792                 } else {
793                         if (!cm->addr_count ||
794                             memcmp(cm->addr[0], addr, sizeof(*addr)))
795                                 continue;
796                         found = 1;
797                         config_item_get(i);
798                         break;
799                 }
800         }
801         up(&clusters_root.subsys.su_sem);
802
803         if (!found)
804                 cm = NULL;
805         return cm;
806 }
807
808 static void put_comm(struct comm *cm)
809 {
810         config_item_put(&cm->item);
811 }
812
813 /* caller must free mem */
814 int dlm_nodeid_list(char *lsname, int **ids_out)
815 {
816         struct space *sp;
817         struct node *nd;
818         int i = 0, rv = 0;
819         int *ids;
820
821         sp = get_space(lsname);
822         if (!sp)
823                 return -EEXIST;
824
825         mutex_lock(&sp->members_lock);
826         if (!sp->members_count) {
827                 rv = 0;
828                 goto out;
829         }
830
831         ids = kcalloc(sp->members_count, sizeof(int), GFP_KERNEL);
832         if (!ids) {
833                 rv = -ENOMEM;
834                 goto out;
835         }
836
837         rv = sp->members_count;
838         list_for_each_entry(nd, &sp->members, list)
839                 ids[i++] = nd->nodeid;
840
841         if (rv != i)
842                 printk("bad nodeid count %d %d\n", rv, i);
843
844         *ids_out = ids;
845  out:
846         mutex_unlock(&sp->members_lock);
847         put_space(sp);
848         return rv;
849 }
850
851 int dlm_node_weight(char *lsname, int nodeid)
852 {
853         struct space *sp;
854         struct node *nd;
855         int w = -EEXIST;
856
857         sp = get_space(lsname);
858         if (!sp)
859                 goto out;
860
861         mutex_lock(&sp->members_lock);
862         list_for_each_entry(nd, &sp->members, list) {
863                 if (nd->nodeid != nodeid)
864                         continue;
865                 w = nd->weight;
866                 break;
867         }
868         mutex_unlock(&sp->members_lock);
869         put_space(sp);
870  out:
871         return w;
872 }
873
874 int dlm_nodeid_to_addr(int nodeid, struct sockaddr_storage *addr)
875 {
876         struct comm *cm = get_comm(nodeid, NULL);
877         if (!cm)
878                 return -EEXIST;
879         if (!cm->addr_count)
880                 return -ENOENT;
881         memcpy(addr, cm->addr[0], sizeof(*addr));
882         put_comm(cm);
883         return 0;
884 }
885
886 int dlm_addr_to_nodeid(struct sockaddr_storage *addr, int *nodeid)
887 {
888         struct comm *cm = get_comm(0, addr);
889         if (!cm)
890                 return -EEXIST;
891         *nodeid = cm->nodeid;
892         put_comm(cm);
893         return 0;
894 }
895
896 int dlm_our_nodeid(void)
897 {
898         return local_comm ? local_comm->nodeid : 0;
899 }
900
901 /* num 0 is first addr, num 1 is second addr */
902 int dlm_our_addr(struct sockaddr_storage *addr, int num)
903 {
904         if (!local_comm)
905                 return -1;
906         if (num + 1 > local_comm->addr_count)
907                 return -1;
908         memcpy(addr, local_comm->addr[num], sizeof(*addr));
909         return 0;
910 }
911
912 /* Config file defaults */
913 #define DEFAULT_TCP_PORT       21064
914 #define DEFAULT_BUFFER_SIZE     4096
915 #define DEFAULT_RSBTBL_SIZE      256
916 #define DEFAULT_LKBTBL_SIZE     1024
917 #define DEFAULT_DIRTBL_SIZE      512
918 #define DEFAULT_RECOVER_TIMER      5
919 #define DEFAULT_TOSS_SECS         10
920 #define DEFAULT_SCAN_SECS          5
921 #define DEFAULT_LOG_DEBUG          0
922 #define DEFAULT_PROTOCOL           0
923 #define DEFAULT_TIMEWARN_CS      500 /* 5 sec = 500 centiseconds */
924
925 struct dlm_config_info dlm_config = {
926         .ci_tcp_port = DEFAULT_TCP_PORT,
927         .ci_buffer_size = DEFAULT_BUFFER_SIZE,
928         .ci_rsbtbl_size = DEFAULT_RSBTBL_SIZE,
929         .ci_lkbtbl_size = DEFAULT_LKBTBL_SIZE,
930         .ci_dirtbl_size = DEFAULT_DIRTBL_SIZE,
931         .ci_recover_timer = DEFAULT_RECOVER_TIMER,
932         .ci_toss_secs = DEFAULT_TOSS_SECS,
933         .ci_scan_secs = DEFAULT_SCAN_SECS,
934         .ci_log_debug = DEFAULT_LOG_DEBUG,
935         .ci_protocol = DEFAULT_PROTOCOL,
936         .ci_timewarn_cs = DEFAULT_TIMEWARN_CS
937 };
938