GFS2: Various gfs2_logd improvements
[pandora-kernel.git] / fs / gfs2 / sys.c
1 /*
2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
3  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
4  *
5  * This copyrighted material is made available to anyone wishing to use,
6  * modify, copy, or redistribute it subject to the terms and conditions
7  * of the GNU General Public License version 2.
8  */
9
10 #include <linux/sched.h>
11 #include <linux/slab.h>
12 #include <linux/spinlock.h>
13 #include <linux/completion.h>
14 #include <linux/buffer_head.h>
15 #include <linux/module.h>
16 #include <linux/kobject.h>
17 #include <asm/uaccess.h>
18 #include <linux/gfs2_ondisk.h>
19 #include <linux/genhd.h>
20
21 #include "gfs2.h"
22 #include "incore.h"
23 #include "sys.h"
24 #include "super.h"
25 #include "glock.h"
26 #include "quota.h"
27 #include "util.h"
28 #include "glops.h"
29
30 struct gfs2_attr {
31         struct attribute attr;
32         ssize_t (*show)(struct gfs2_sbd *, char *);
33         ssize_t (*store)(struct gfs2_sbd *, const char *, size_t);
34 };
35
36 static ssize_t gfs2_attr_show(struct kobject *kobj, struct attribute *attr,
37                               char *buf)
38 {
39         struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
40         struct gfs2_attr *a = container_of(attr, struct gfs2_attr, attr);
41         return a->show ? a->show(sdp, buf) : 0;
42 }
43
44 static ssize_t gfs2_attr_store(struct kobject *kobj, struct attribute *attr,
45                                const char *buf, size_t len)
46 {
47         struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
48         struct gfs2_attr *a = container_of(attr, struct gfs2_attr, attr);
49         return a->store ? a->store(sdp, buf, len) : len;
50 }
51
52 static const struct sysfs_ops gfs2_attr_ops = {
53         .show  = gfs2_attr_show,
54         .store = gfs2_attr_store,
55 };
56
57
58 static struct kset *gfs2_kset;
59
60 static ssize_t id_show(struct gfs2_sbd *sdp, char *buf)
61 {
62         return snprintf(buf, PAGE_SIZE, "%u:%u\n",
63                         MAJOR(sdp->sd_vfs->s_dev), MINOR(sdp->sd_vfs->s_dev));
64 }
65
66 static ssize_t fsname_show(struct gfs2_sbd *sdp, char *buf)
67 {
68         return snprintf(buf, PAGE_SIZE, "%s\n", sdp->sd_fsname);
69 }
70
71 static int gfs2_uuid_valid(const u8 *uuid)
72 {
73         int i;
74
75         for (i = 0; i < 16; i++) {
76                 if (uuid[i])
77                         return 1;
78         }
79         return 0;
80 }
81
82 static ssize_t uuid_show(struct gfs2_sbd *sdp, char *buf)
83 {
84         const u8 *uuid = sdp->sd_sb.sb_uuid;
85         buf[0] = '\0';
86         if (!gfs2_uuid_valid(uuid))
87                 return 0;
88         return snprintf(buf, PAGE_SIZE, "%pUB\n", uuid);
89 }
90
91 static ssize_t freeze_show(struct gfs2_sbd *sdp, char *buf)
92 {
93         unsigned int count;
94
95         mutex_lock(&sdp->sd_freeze_lock);
96         count = sdp->sd_freeze_count;
97         mutex_unlock(&sdp->sd_freeze_lock);
98
99         return snprintf(buf, PAGE_SIZE, "%u\n", count);
100 }
101
102 static ssize_t freeze_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
103 {
104         ssize_t ret = len;
105         int error = 0;
106         int n = simple_strtol(buf, NULL, 0);
107
108         if (!capable(CAP_SYS_ADMIN))
109                 return -EACCES;
110
111         switch (n) {
112         case 0:
113                 gfs2_unfreeze_fs(sdp);
114                 break;
115         case 1:
116                 error = gfs2_freeze_fs(sdp);
117                 break;
118         default:
119                 ret = -EINVAL;
120         }
121
122         if (error)
123                 fs_warn(sdp, "freeze %d error %d", n, error);
124
125         return ret;
126 }
127
128 static ssize_t withdraw_show(struct gfs2_sbd *sdp, char *buf)
129 {
130         unsigned int b = test_bit(SDF_SHUTDOWN, &sdp->sd_flags);
131         return snprintf(buf, PAGE_SIZE, "%u\n", b);
132 }
133
134 static ssize_t withdraw_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
135 {
136         if (!capable(CAP_SYS_ADMIN))
137                 return -EACCES;
138
139         if (simple_strtol(buf, NULL, 0) != 1)
140                 return -EINVAL;
141
142         gfs2_lm_withdraw(sdp,
143                 "GFS2: fsid=%s: withdrawing from cluster at user's request\n",
144                 sdp->sd_fsname);
145         return len;
146 }
147
148 static ssize_t statfs_sync_store(struct gfs2_sbd *sdp, const char *buf,
149                                  size_t len)
150 {
151         if (!capable(CAP_SYS_ADMIN))
152                 return -EACCES;
153
154         if (simple_strtol(buf, NULL, 0) != 1)
155                 return -EINVAL;
156
157         gfs2_statfs_sync(sdp->sd_vfs, 0);
158         return len;
159 }
160
161 static ssize_t quota_sync_store(struct gfs2_sbd *sdp, const char *buf,
162                                 size_t len)
163 {
164         if (!capable(CAP_SYS_ADMIN))
165                 return -EACCES;
166
167         if (simple_strtol(buf, NULL, 0) != 1)
168                 return -EINVAL;
169
170         gfs2_quota_sync(sdp->sd_vfs, 0, 1);
171         return len;
172 }
173
174 static ssize_t quota_refresh_user_store(struct gfs2_sbd *sdp, const char *buf,
175                                         size_t len)
176 {
177         int error;
178         u32 id;
179
180         if (!capable(CAP_SYS_ADMIN))
181                 return -EACCES;
182
183         id = simple_strtoul(buf, NULL, 0);
184
185         error = gfs2_quota_refresh(sdp, 1, id);
186         return error ? error : len;
187 }
188
189 static ssize_t quota_refresh_group_store(struct gfs2_sbd *sdp, const char *buf,
190                                          size_t len)
191 {
192         int error;
193         u32 id;
194
195         if (!capable(CAP_SYS_ADMIN))
196                 return -EACCES;
197
198         id = simple_strtoul(buf, NULL, 0);
199
200         error = gfs2_quota_refresh(sdp, 0, id);
201         return error ? error : len;
202 }
203
204 static ssize_t demote_rq_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
205 {
206         struct gfs2_glock *gl;
207         const struct gfs2_glock_operations *glops;
208         unsigned int glmode;
209         unsigned int gltype;
210         unsigned long long glnum;
211         char mode[16];
212         int rv;
213
214         if (!capable(CAP_SYS_ADMIN))
215                 return -EACCES;
216
217         rv = sscanf(buf, "%u:%llu %15s", &gltype, &glnum,
218                     mode);
219         if (rv != 3)
220                 return -EINVAL;
221
222         if (strcmp(mode, "EX") == 0)
223                 glmode = LM_ST_UNLOCKED;
224         else if ((strcmp(mode, "CW") == 0) || (strcmp(mode, "DF") == 0))
225                 glmode = LM_ST_DEFERRED;
226         else if ((strcmp(mode, "PR") == 0) || (strcmp(mode, "SH") == 0))
227                 glmode = LM_ST_SHARED;
228         else
229                 return -EINVAL;
230
231         if (gltype > LM_TYPE_JOURNAL)
232                 return -EINVAL;
233         glops = gfs2_glops_list[gltype];
234         if (glops == NULL)
235                 return -EINVAL;
236         rv = gfs2_glock_get(sdp, glnum, glops, 0, &gl);
237         if (rv)
238                 return rv;
239         gfs2_glock_cb(gl, glmode);
240         gfs2_glock_put(gl);
241         return len;
242 }
243
244
245 #define GFS2_ATTR(name, mode, show, store) \
246 static struct gfs2_attr gfs2_attr_##name = __ATTR(name, mode, show, store)
247
248 GFS2_ATTR(id,                  0444, id_show,       NULL);
249 GFS2_ATTR(fsname,              0444, fsname_show,   NULL);
250 GFS2_ATTR(uuid,                0444, uuid_show,     NULL);
251 GFS2_ATTR(freeze,              0644, freeze_show,   freeze_store);
252 GFS2_ATTR(withdraw,            0644, withdraw_show, withdraw_store);
253 GFS2_ATTR(statfs_sync,         0200, NULL,          statfs_sync_store);
254 GFS2_ATTR(quota_sync,          0200, NULL,          quota_sync_store);
255 GFS2_ATTR(quota_refresh_user,  0200, NULL,          quota_refresh_user_store);
256 GFS2_ATTR(quota_refresh_group, 0200, NULL,          quota_refresh_group_store);
257 GFS2_ATTR(demote_rq,           0200, NULL,          demote_rq_store);
258
259 static struct attribute *gfs2_attrs[] = {
260         &gfs2_attr_id.attr,
261         &gfs2_attr_fsname.attr,
262         &gfs2_attr_uuid.attr,
263         &gfs2_attr_freeze.attr,
264         &gfs2_attr_withdraw.attr,
265         &gfs2_attr_statfs_sync.attr,
266         &gfs2_attr_quota_sync.attr,
267         &gfs2_attr_quota_refresh_user.attr,
268         &gfs2_attr_quota_refresh_group.attr,
269         &gfs2_attr_demote_rq.attr,
270         NULL,
271 };
272
273 static struct kobj_type gfs2_ktype = {
274         .default_attrs = gfs2_attrs,
275         .sysfs_ops     = &gfs2_attr_ops,
276 };
277
278
279 /*
280  * lock_module. Originally from lock_dlm
281  */
282
283 static ssize_t proto_name_show(struct gfs2_sbd *sdp, char *buf)
284 {
285         const struct lm_lockops *ops = sdp->sd_lockstruct.ls_ops;
286         return sprintf(buf, "%s\n", ops->lm_proto_name);
287 }
288
289 static ssize_t block_show(struct gfs2_sbd *sdp, char *buf)
290 {
291         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
292         ssize_t ret;
293         int val = 0;
294
295         if (test_bit(DFL_BLOCK_LOCKS, &ls->ls_flags))
296                 val = 1;
297         ret = sprintf(buf, "%d\n", val);
298         return ret;
299 }
300
301 static ssize_t block_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
302 {
303         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
304         ssize_t ret = len;
305         int val;
306
307         val = simple_strtol(buf, NULL, 0);
308
309         if (val == 1)
310                 set_bit(DFL_BLOCK_LOCKS, &ls->ls_flags);
311         else if (val == 0) {
312                 clear_bit(DFL_BLOCK_LOCKS, &ls->ls_flags);
313                 smp_mb__after_clear_bit();
314                 gfs2_glock_thaw(sdp);
315         } else {
316                 ret = -EINVAL;
317         }
318         return ret;
319 }
320
321 static ssize_t lkfirst_show(struct gfs2_sbd *sdp, char *buf)
322 {
323         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
324         return sprintf(buf, "%d\n", ls->ls_first);
325 }
326
327 static ssize_t first_done_show(struct gfs2_sbd *sdp, char *buf)
328 {
329         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
330         return sprintf(buf, "%d\n", ls->ls_first_done);
331 }
332
333 static ssize_t recover_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
334 {
335         unsigned jid;
336         struct gfs2_jdesc *jd;
337         int rv;
338
339         rv = sscanf(buf, "%u", &jid);
340         if (rv != 1)
341                 return -EINVAL;
342
343         rv = -ESHUTDOWN;
344         spin_lock(&sdp->sd_jindex_spin);
345         if (test_bit(SDF_NORECOVERY, &sdp->sd_flags))
346                 goto out;
347         rv = -EBUSY;
348         if (sdp->sd_jdesc->jd_jid == jid)
349                 goto out;
350         rv = -ENOENT;
351         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
352                 if (jd->jd_jid != jid)
353                         continue;
354                 rv = slow_work_enqueue(&jd->jd_work);
355                 break;
356         }
357 out:
358         spin_unlock(&sdp->sd_jindex_spin);
359         return rv ? rv : len;
360 }
361
362 static ssize_t recover_done_show(struct gfs2_sbd *sdp, char *buf)
363 {
364         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
365         return sprintf(buf, "%d\n", ls->ls_recover_jid_done);
366 }
367
368 static ssize_t recover_status_show(struct gfs2_sbd *sdp, char *buf)
369 {
370         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
371         return sprintf(buf, "%d\n", ls->ls_recover_jid_status);
372 }
373
374 static ssize_t jid_show(struct gfs2_sbd *sdp, char *buf)
375 {
376         return sprintf(buf, "%u\n", sdp->sd_lockstruct.ls_jid);
377 }
378
379 #define GDLM_ATTR(_name,_mode,_show,_store) \
380 static struct gfs2_attr gdlm_attr_##_name = __ATTR(_name,_mode,_show,_store)
381
382 GDLM_ATTR(proto_name,           0444, proto_name_show,          NULL);
383 GDLM_ATTR(block,                0644, block_show,               block_store);
384 GDLM_ATTR(withdraw,             0644, withdraw_show,            withdraw_store);
385 GDLM_ATTR(jid,                  0444, jid_show,                 NULL);
386 GDLM_ATTR(first,                0444, lkfirst_show,             NULL);
387 GDLM_ATTR(first_done,           0444, first_done_show,          NULL);
388 GDLM_ATTR(recover,              0600, NULL,                     recover_store);
389 GDLM_ATTR(recover_done,         0444, recover_done_show,        NULL);
390 GDLM_ATTR(recover_status,       0444, recover_status_show,      NULL);
391
392 static struct attribute *lock_module_attrs[] = {
393         &gdlm_attr_proto_name.attr,
394         &gdlm_attr_block.attr,
395         &gdlm_attr_withdraw.attr,
396         &gdlm_attr_jid.attr,
397         &gdlm_attr_first.attr,
398         &gdlm_attr_first_done.attr,
399         &gdlm_attr_recover.attr,
400         &gdlm_attr_recover_done.attr,
401         &gdlm_attr_recover_status.attr,
402         NULL,
403 };
404
405 /*
406  * get and set struct gfs2_tune fields
407  */
408
409 static ssize_t quota_scale_show(struct gfs2_sbd *sdp, char *buf)
410 {
411         return snprintf(buf, PAGE_SIZE, "%u %u\n",
412                         sdp->sd_tune.gt_quota_scale_num,
413                         sdp->sd_tune.gt_quota_scale_den);
414 }
415
416 static ssize_t quota_scale_store(struct gfs2_sbd *sdp, const char *buf,
417                                  size_t len)
418 {
419         struct gfs2_tune *gt = &sdp->sd_tune;
420         unsigned int x, y;
421
422         if (!capable(CAP_SYS_ADMIN))
423                 return -EACCES;
424
425         if (sscanf(buf, "%u %u", &x, &y) != 2 || !y)
426                 return -EINVAL;
427
428         spin_lock(&gt->gt_spin);
429         gt->gt_quota_scale_num = x;
430         gt->gt_quota_scale_den = y;
431         spin_unlock(&gt->gt_spin);
432         return len;
433 }
434
435 static ssize_t tune_set(struct gfs2_sbd *sdp, unsigned int *field,
436                         int check_zero, const char *buf, size_t len)
437 {
438         struct gfs2_tune *gt = &sdp->sd_tune;
439         unsigned int x;
440
441         if (!capable(CAP_SYS_ADMIN))
442                 return -EACCES;
443
444         x = simple_strtoul(buf, NULL, 0);
445
446         if (check_zero && !x)
447                 return -EINVAL;
448
449         spin_lock(&gt->gt_spin);
450         *field = x;
451         spin_unlock(&gt->gt_spin);
452         return len;
453 }
454
455 #define TUNE_ATTR_3(name, show, store)                                        \
456 static struct gfs2_attr tune_attr_##name = __ATTR(name, 0644, show, store)
457
458 #define TUNE_ATTR_2(name, store)                                              \
459 static ssize_t name##_show(struct gfs2_sbd *sdp, char *buf)                   \
460 {                                                                             \
461         return snprintf(buf, PAGE_SIZE, "%u\n", sdp->sd_tune.gt_##name);      \
462 }                                                                             \
463 TUNE_ATTR_3(name, name##_show, store)
464
465 #define TUNE_ATTR(name, check_zero)                                           \
466 static ssize_t name##_store(struct gfs2_sbd *sdp, const char *buf, size_t len)\
467 {                                                                             \
468         return tune_set(sdp, &sdp->sd_tune.gt_##name, check_zero, buf, len);  \
469 }                                                                             \
470 TUNE_ATTR_2(name, name##_store)
471
472 TUNE_ATTR(quota_warn_period, 0);
473 TUNE_ATTR(quota_quantum, 0);
474 TUNE_ATTR(max_readahead, 0);
475 TUNE_ATTR(complain_secs, 0);
476 TUNE_ATTR(statfs_slow, 0);
477 TUNE_ATTR(new_files_jdata, 0);
478 TUNE_ATTR(quota_simul_sync, 1);
479 TUNE_ATTR(statfs_quantum, 1);
480 TUNE_ATTR_3(quota_scale, quota_scale_show, quota_scale_store);
481
482 static struct attribute *tune_attrs[] = {
483         &tune_attr_quota_warn_period.attr,
484         &tune_attr_quota_quantum.attr,
485         &tune_attr_max_readahead.attr,
486         &tune_attr_complain_secs.attr,
487         &tune_attr_statfs_slow.attr,
488         &tune_attr_quota_simul_sync.attr,
489         &tune_attr_statfs_quantum.attr,
490         &tune_attr_quota_scale.attr,
491         &tune_attr_new_files_jdata.attr,
492         NULL,
493 };
494
495 static struct attribute_group tune_group = {
496         .name = "tune",
497         .attrs = tune_attrs,
498 };
499
500 static struct attribute_group lock_module_group = {
501         .name = "lock_module",
502         .attrs = lock_module_attrs,
503 };
504
505 int gfs2_sys_fs_add(struct gfs2_sbd *sdp)
506 {
507         struct super_block *sb = sdp->sd_vfs;
508         int error;
509         char ro[20];
510         char spectator[20];
511         char *envp[] = { ro, spectator, NULL };
512
513         sprintf(ro, "RDONLY=%d", (sb->s_flags & MS_RDONLY) ? 1 : 0);
514         sprintf(spectator, "SPECTATOR=%d", sdp->sd_args.ar_spectator ? 1 : 0);
515
516         sdp->sd_kobj.kset = gfs2_kset;
517         error = kobject_init_and_add(&sdp->sd_kobj, &gfs2_ktype, NULL,
518                                      "%s", sdp->sd_table_name);
519         if (error)
520                 goto fail;
521
522         error = sysfs_create_group(&sdp->sd_kobj, &tune_group);
523         if (error)
524                 goto fail_reg;
525
526         error = sysfs_create_group(&sdp->sd_kobj, &lock_module_group);
527         if (error)
528                 goto fail_tune;
529
530         error = sysfs_create_link(&sdp->sd_kobj,
531                                   &disk_to_dev(sb->s_bdev->bd_disk)->kobj,
532                                   "device");
533         if (error)
534                 goto fail_lock_module;
535
536         kobject_uevent_env(&sdp->sd_kobj, KOBJ_ADD, envp);
537         return 0;
538
539 fail_lock_module:
540         sysfs_remove_group(&sdp->sd_kobj, &lock_module_group);
541 fail_tune:
542         sysfs_remove_group(&sdp->sd_kobj, &tune_group);
543 fail_reg:
544         kobject_put(&sdp->sd_kobj);
545 fail:
546         fs_err(sdp, "error %d adding sysfs files", error);
547         return error;
548 }
549
550 void gfs2_sys_fs_del(struct gfs2_sbd *sdp)
551 {
552         sysfs_remove_link(&sdp->sd_kobj, "device");
553         sysfs_remove_group(&sdp->sd_kobj, &tune_group);
554         sysfs_remove_group(&sdp->sd_kobj, &lock_module_group);
555         kobject_put(&sdp->sd_kobj);
556 }
557
558 static int gfs2_uevent(struct kset *kset, struct kobject *kobj,
559                        struct kobj_uevent_env *env)
560 {
561         struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
562         const u8 *uuid = sdp->sd_sb.sb_uuid;
563
564         add_uevent_var(env, "LOCKTABLE=%s", sdp->sd_table_name);
565         add_uevent_var(env, "LOCKPROTO=%s", sdp->sd_proto_name);
566         if (!sdp->sd_args.ar_spectator)
567                 add_uevent_var(env, "JOURNALID=%u", sdp->sd_lockstruct.ls_jid);
568         if (gfs2_uuid_valid(uuid))
569                 add_uevent_var(env, "UUID=%pUB", uuid);
570         return 0;
571 }
572
573 static const struct kset_uevent_ops gfs2_uevent_ops = {
574         .uevent = gfs2_uevent,
575 };
576
577 int gfs2_sys_init(void)
578 {
579         gfs2_kset = kset_create_and_add("gfs2", &gfs2_uevent_ops, fs_kobj);
580         if (!gfs2_kset)
581                 return -ENOMEM;
582         return 0;
583 }
584
585 void gfs2_sys_uninit(void)
586 {
587         kset_unregister(gfs2_kset);
588 }
589