Merge branch 'viafb-next' of git://git.lwn.net/linux-2.6
[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/spinlock.h>
12 #include <linux/completion.h>
13 #include <linux/buffer_head.h>
14 #include <linux/module.h>
15 #include <linux/kobject.h>
16 #include <asm/uaccess.h>
17 #include <linux/gfs2_ondisk.h>
18 #include <linux/genhd.h>
19
20 #include "gfs2.h"
21 #include "incore.h"
22 #include "sys.h"
23 #include "super.h"
24 #include "glock.h"
25 #include "quota.h"
26 #include "util.h"
27 #include "glops.h"
28
29 struct gfs2_attr {
30         struct attribute attr;
31         ssize_t (*show)(struct gfs2_sbd *, char *);
32         ssize_t (*store)(struct gfs2_sbd *, const char *, size_t);
33 };
34
35 static ssize_t gfs2_attr_show(struct kobject *kobj, struct attribute *attr,
36                               char *buf)
37 {
38         struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
39         struct gfs2_attr *a = container_of(attr, struct gfs2_attr, attr);
40         return a->show ? a->show(sdp, buf) : 0;
41 }
42
43 static ssize_t gfs2_attr_store(struct kobject *kobj, struct attribute *attr,
44                                const char *buf, size_t len)
45 {
46         struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
47         struct gfs2_attr *a = container_of(attr, struct gfs2_attr, attr);
48         return a->store ? a->store(sdp, buf, len) : len;
49 }
50
51 static const struct sysfs_ops gfs2_attr_ops = {
52         .show  = gfs2_attr_show,
53         .store = gfs2_attr_store,
54 };
55
56
57 static struct kset *gfs2_kset;
58
59 static ssize_t id_show(struct gfs2_sbd *sdp, char *buf)
60 {
61         return snprintf(buf, PAGE_SIZE, "%u:%u\n",
62                         MAJOR(sdp->sd_vfs->s_dev), MINOR(sdp->sd_vfs->s_dev));
63 }
64
65 static ssize_t fsname_show(struct gfs2_sbd *sdp, char *buf)
66 {
67         return snprintf(buf, PAGE_SIZE, "%s\n", sdp->sd_fsname);
68 }
69
70 static int gfs2_uuid_valid(const u8 *uuid)
71 {
72         int i;
73
74         for (i = 0; i < 16; i++) {
75                 if (uuid[i])
76                         return 1;
77         }
78         return 0;
79 }
80
81 static ssize_t uuid_show(struct gfs2_sbd *sdp, char *buf)
82 {
83         const u8 *uuid = sdp->sd_sb.sb_uuid;
84         buf[0] = '\0';
85         if (!gfs2_uuid_valid(uuid))
86                 return 0;
87         return snprintf(buf, PAGE_SIZE, "%pUB\n", uuid);
88 }
89
90 static ssize_t freeze_show(struct gfs2_sbd *sdp, char *buf)
91 {
92         unsigned int count;
93
94         mutex_lock(&sdp->sd_freeze_lock);
95         count = sdp->sd_freeze_count;
96         mutex_unlock(&sdp->sd_freeze_lock);
97
98         return snprintf(buf, PAGE_SIZE, "%u\n", count);
99 }
100
101 static ssize_t freeze_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
102 {
103         ssize_t ret = len;
104         int error = 0;
105         int n = simple_strtol(buf, NULL, 0);
106
107         if (!capable(CAP_SYS_ADMIN))
108                 return -EACCES;
109
110         switch (n) {
111         case 0:
112                 gfs2_unfreeze_fs(sdp);
113                 break;
114         case 1:
115                 error = gfs2_freeze_fs(sdp);
116                 break;
117         default:
118                 ret = -EINVAL;
119         }
120
121         if (error)
122                 fs_warn(sdp, "freeze %d error %d", n, error);
123
124         return ret;
125 }
126
127 static ssize_t withdraw_show(struct gfs2_sbd *sdp, char *buf)
128 {
129         unsigned int b = test_bit(SDF_SHUTDOWN, &sdp->sd_flags);
130         return snprintf(buf, PAGE_SIZE, "%u\n", b);
131 }
132
133 static ssize_t withdraw_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
134 {
135         if (!capable(CAP_SYS_ADMIN))
136                 return -EACCES;
137
138         if (simple_strtol(buf, NULL, 0) != 1)
139                 return -EINVAL;
140
141         gfs2_lm_withdraw(sdp,
142                 "GFS2: fsid=%s: withdrawing from cluster at user's request\n",
143                 sdp->sd_fsname);
144         return len;
145 }
146
147 static ssize_t statfs_sync_store(struct gfs2_sbd *sdp, const char *buf,
148                                  size_t len)
149 {
150         if (!capable(CAP_SYS_ADMIN))
151                 return -EACCES;
152
153         if (simple_strtol(buf, NULL, 0) != 1)
154                 return -EINVAL;
155
156         gfs2_statfs_sync(sdp->sd_vfs, 0);
157         return len;
158 }
159
160 static ssize_t quota_sync_store(struct gfs2_sbd *sdp, const char *buf,
161                                 size_t len)
162 {
163         if (!capable(CAP_SYS_ADMIN))
164                 return -EACCES;
165
166         if (simple_strtol(buf, NULL, 0) != 1)
167                 return -EINVAL;
168
169         gfs2_quota_sync(sdp->sd_vfs, 0, 1);
170         return len;
171 }
172
173 static ssize_t quota_refresh_user_store(struct gfs2_sbd *sdp, const char *buf,
174                                         size_t len)
175 {
176         int error;
177         u32 id;
178
179         if (!capable(CAP_SYS_ADMIN))
180                 return -EACCES;
181
182         id = simple_strtoul(buf, NULL, 0);
183
184         error = gfs2_quota_refresh(sdp, 1, id);
185         return error ? error : len;
186 }
187
188 static ssize_t quota_refresh_group_store(struct gfs2_sbd *sdp, const char *buf,
189                                          size_t len)
190 {
191         int error;
192         u32 id;
193
194         if (!capable(CAP_SYS_ADMIN))
195                 return -EACCES;
196
197         id = simple_strtoul(buf, NULL, 0);
198
199         error = gfs2_quota_refresh(sdp, 0, id);
200         return error ? error : len;
201 }
202
203 static ssize_t demote_rq_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
204 {
205         struct gfs2_glock *gl;
206         const struct gfs2_glock_operations *glops;
207         unsigned int glmode;
208         unsigned int gltype;
209         unsigned long long glnum;
210         char mode[16];
211         int rv;
212
213         if (!capable(CAP_SYS_ADMIN))
214                 return -EACCES;
215
216         rv = sscanf(buf, "%u:%llu %15s", &gltype, &glnum,
217                     mode);
218         if (rv != 3)
219                 return -EINVAL;
220
221         if (strcmp(mode, "EX") == 0)
222                 glmode = LM_ST_UNLOCKED;
223         else if ((strcmp(mode, "CW") == 0) || (strcmp(mode, "DF") == 0))
224                 glmode = LM_ST_DEFERRED;
225         else if ((strcmp(mode, "PR") == 0) || (strcmp(mode, "SH") == 0))
226                 glmode = LM_ST_SHARED;
227         else
228                 return -EINVAL;
229
230         if (gltype > LM_TYPE_JOURNAL)
231                 return -EINVAL;
232         glops = gfs2_glops_list[gltype];
233         if (glops == NULL)
234                 return -EINVAL;
235         rv = gfs2_glock_get(sdp, glnum, glops, 0, &gl);
236         if (rv)
237                 return rv;
238         gfs2_glock_cb(gl, glmode);
239         gfs2_glock_put(gl);
240         return len;
241 }
242
243
244 #define GFS2_ATTR(name, mode, show, store) \
245 static struct gfs2_attr gfs2_attr_##name = __ATTR(name, mode, show, store)
246
247 GFS2_ATTR(id,                  0444, id_show,       NULL);
248 GFS2_ATTR(fsname,              0444, fsname_show,   NULL);
249 GFS2_ATTR(uuid,                0444, uuid_show,     NULL);
250 GFS2_ATTR(freeze,              0644, freeze_show,   freeze_store);
251 GFS2_ATTR(withdraw,            0644, withdraw_show, withdraw_store);
252 GFS2_ATTR(statfs_sync,         0200, NULL,          statfs_sync_store);
253 GFS2_ATTR(quota_sync,          0200, NULL,          quota_sync_store);
254 GFS2_ATTR(quota_refresh_user,  0200, NULL,          quota_refresh_user_store);
255 GFS2_ATTR(quota_refresh_group, 0200, NULL,          quota_refresh_group_store);
256 GFS2_ATTR(demote_rq,           0200, NULL,          demote_rq_store);
257
258 static struct attribute *gfs2_attrs[] = {
259         &gfs2_attr_id.attr,
260         &gfs2_attr_fsname.attr,
261         &gfs2_attr_uuid.attr,
262         &gfs2_attr_freeze.attr,
263         &gfs2_attr_withdraw.attr,
264         &gfs2_attr_statfs_sync.attr,
265         &gfs2_attr_quota_sync.attr,
266         &gfs2_attr_quota_refresh_user.attr,
267         &gfs2_attr_quota_refresh_group.attr,
268         &gfs2_attr_demote_rq.attr,
269         NULL,
270 };
271
272 static struct kobj_type gfs2_ktype = {
273         .default_attrs = gfs2_attrs,
274         .sysfs_ops     = &gfs2_attr_ops,
275 };
276
277
278 /*
279  * lock_module. Originally from lock_dlm
280  */
281
282 static ssize_t proto_name_show(struct gfs2_sbd *sdp, char *buf)
283 {
284         const struct lm_lockops *ops = sdp->sd_lockstruct.ls_ops;
285         return sprintf(buf, "%s\n", ops->lm_proto_name);
286 }
287
288 static ssize_t block_show(struct gfs2_sbd *sdp, char *buf)
289 {
290         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
291         ssize_t ret;
292         int val = 0;
293
294         if (test_bit(DFL_BLOCK_LOCKS, &ls->ls_flags))
295                 val = 1;
296         ret = sprintf(buf, "%d\n", val);
297         return ret;
298 }
299
300 static ssize_t block_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
301 {
302         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
303         ssize_t ret = len;
304         int val;
305
306         val = simple_strtol(buf, NULL, 0);
307
308         if (val == 1)
309                 set_bit(DFL_BLOCK_LOCKS, &ls->ls_flags);
310         else if (val == 0) {
311                 clear_bit(DFL_BLOCK_LOCKS, &ls->ls_flags);
312                 smp_mb__after_clear_bit();
313                 gfs2_glock_thaw(sdp);
314         } else {
315                 ret = -EINVAL;
316         }
317         return ret;
318 }
319
320 static ssize_t lkfirst_show(struct gfs2_sbd *sdp, char *buf)
321 {
322         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
323         return sprintf(buf, "%d\n", ls->ls_first);
324 }
325
326 static ssize_t first_done_show(struct gfs2_sbd *sdp, char *buf)
327 {
328         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
329         return sprintf(buf, "%d\n", ls->ls_first_done);
330 }
331
332 static ssize_t recover_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
333 {
334         unsigned jid;
335         struct gfs2_jdesc *jd;
336         int rv;
337
338         rv = sscanf(buf, "%u", &jid);
339         if (rv != 1)
340                 return -EINVAL;
341
342         rv = -ESHUTDOWN;
343         spin_lock(&sdp->sd_jindex_spin);
344         if (test_bit(SDF_NORECOVERY, &sdp->sd_flags))
345                 goto out;
346         rv = -EBUSY;
347         if (sdp->sd_jdesc->jd_jid == jid)
348                 goto out;
349         rv = -ENOENT;
350         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
351                 if (jd->jd_jid != jid)
352                         continue;
353                 rv = slow_work_enqueue(&jd->jd_work);
354                 break;
355         }
356 out:
357         spin_unlock(&sdp->sd_jindex_spin);
358         return rv ? rv : len;
359 }
360
361 static ssize_t recover_done_show(struct gfs2_sbd *sdp, char *buf)
362 {
363         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
364         return sprintf(buf, "%d\n", ls->ls_recover_jid_done);
365 }
366
367 static ssize_t recover_status_show(struct gfs2_sbd *sdp, char *buf)
368 {
369         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
370         return sprintf(buf, "%d\n", ls->ls_recover_jid_status);
371 }
372
373 static ssize_t jid_show(struct gfs2_sbd *sdp, char *buf)
374 {
375         return sprintf(buf, "%u\n", sdp->sd_lockstruct.ls_jid);
376 }
377
378 #define GDLM_ATTR(_name,_mode,_show,_store) \
379 static struct gfs2_attr gdlm_attr_##_name = __ATTR(_name,_mode,_show,_store)
380
381 GDLM_ATTR(proto_name,           0444, proto_name_show,          NULL);
382 GDLM_ATTR(block,                0644, block_show,               block_store);
383 GDLM_ATTR(withdraw,             0644, withdraw_show,            withdraw_store);
384 GDLM_ATTR(jid,                  0444, jid_show,                 NULL);
385 GDLM_ATTR(first,                0444, lkfirst_show,             NULL);
386 GDLM_ATTR(first_done,           0444, first_done_show,          NULL);
387 GDLM_ATTR(recover,              0600, NULL,                     recover_store);
388 GDLM_ATTR(recover_done,         0444, recover_done_show,        NULL);
389 GDLM_ATTR(recover_status,       0444, recover_status_show,      NULL);
390
391 static struct attribute *lock_module_attrs[] = {
392         &gdlm_attr_proto_name.attr,
393         &gdlm_attr_block.attr,
394         &gdlm_attr_withdraw.attr,
395         &gdlm_attr_jid.attr,
396         &gdlm_attr_first.attr,
397         &gdlm_attr_first_done.attr,
398         &gdlm_attr_recover.attr,
399         &gdlm_attr_recover_done.attr,
400         &gdlm_attr_recover_status.attr,
401         NULL,
402 };
403
404 /*
405  * get and set struct gfs2_tune fields
406  */
407
408 static ssize_t quota_scale_show(struct gfs2_sbd *sdp, char *buf)
409 {
410         return snprintf(buf, PAGE_SIZE, "%u %u\n",
411                         sdp->sd_tune.gt_quota_scale_num,
412                         sdp->sd_tune.gt_quota_scale_den);
413 }
414
415 static ssize_t quota_scale_store(struct gfs2_sbd *sdp, const char *buf,
416                                  size_t len)
417 {
418         struct gfs2_tune *gt = &sdp->sd_tune;
419         unsigned int x, y;
420
421         if (!capable(CAP_SYS_ADMIN))
422                 return -EACCES;
423
424         if (sscanf(buf, "%u %u", &x, &y) != 2 || !y)
425                 return -EINVAL;
426
427         spin_lock(&gt->gt_spin);
428         gt->gt_quota_scale_num = x;
429         gt->gt_quota_scale_den = y;
430         spin_unlock(&gt->gt_spin);
431         return len;
432 }
433
434 static ssize_t tune_set(struct gfs2_sbd *sdp, unsigned int *field,
435                         int check_zero, const char *buf, size_t len)
436 {
437         struct gfs2_tune *gt = &sdp->sd_tune;
438         unsigned int x;
439
440         if (!capable(CAP_SYS_ADMIN))
441                 return -EACCES;
442
443         x = simple_strtoul(buf, NULL, 0);
444
445         if (check_zero && !x)
446                 return -EINVAL;
447
448         spin_lock(&gt->gt_spin);
449         *field = x;
450         spin_unlock(&gt->gt_spin);
451         return len;
452 }
453
454 #define TUNE_ATTR_3(name, show, store)                                        \
455 static struct gfs2_attr tune_attr_##name = __ATTR(name, 0644, show, store)
456
457 #define TUNE_ATTR_2(name, store)                                              \
458 static ssize_t name##_show(struct gfs2_sbd *sdp, char *buf)                   \
459 {                                                                             \
460         return snprintf(buf, PAGE_SIZE, "%u\n", sdp->sd_tune.gt_##name);      \
461 }                                                                             \
462 TUNE_ATTR_3(name, name##_show, store)
463
464 #define TUNE_ATTR(name, check_zero)                                           \
465 static ssize_t name##_store(struct gfs2_sbd *sdp, const char *buf, size_t len)\
466 {                                                                             \
467         return tune_set(sdp, &sdp->sd_tune.gt_##name, check_zero, buf, len);  \
468 }                                                                             \
469 TUNE_ATTR_2(name, name##_store)
470
471 TUNE_ATTR(incore_log_blocks, 0);
472 TUNE_ATTR(log_flush_secs, 0);
473 TUNE_ATTR(quota_warn_period, 0);
474 TUNE_ATTR(quota_quantum, 0);
475 TUNE_ATTR(max_readahead, 0);
476 TUNE_ATTR(complain_secs, 0);
477 TUNE_ATTR(statfs_slow, 0);
478 TUNE_ATTR(new_files_jdata, 0);
479 TUNE_ATTR(quota_simul_sync, 1);
480 TUNE_ATTR(statfs_quantum, 1);
481 TUNE_ATTR_3(quota_scale, quota_scale_show, quota_scale_store);
482
483 static struct attribute *tune_attrs[] = {
484         &tune_attr_incore_log_blocks.attr,
485         &tune_attr_log_flush_secs.attr,
486         &tune_attr_quota_warn_period.attr,
487         &tune_attr_quota_quantum.attr,
488         &tune_attr_max_readahead.attr,
489         &tune_attr_complain_secs.attr,
490         &tune_attr_statfs_slow.attr,
491         &tune_attr_quota_simul_sync.attr,
492         &tune_attr_statfs_quantum.attr,
493         &tune_attr_quota_scale.attr,
494         &tune_attr_new_files_jdata.attr,
495         NULL,
496 };
497
498 static struct attribute_group tune_group = {
499         .name = "tune",
500         .attrs = tune_attrs,
501 };
502
503 static struct attribute_group lock_module_group = {
504         .name = "lock_module",
505         .attrs = lock_module_attrs,
506 };
507
508 int gfs2_sys_fs_add(struct gfs2_sbd *sdp)
509 {
510         struct super_block *sb = sdp->sd_vfs;
511         int error;
512         char ro[20];
513         char spectator[20];
514         char *envp[] = { ro, spectator, NULL };
515
516         sprintf(ro, "RDONLY=%d", (sb->s_flags & MS_RDONLY) ? 1 : 0);
517         sprintf(spectator, "SPECTATOR=%d", sdp->sd_args.ar_spectator ? 1 : 0);
518
519         sdp->sd_kobj.kset = gfs2_kset;
520         error = kobject_init_and_add(&sdp->sd_kobj, &gfs2_ktype, NULL,
521                                      "%s", sdp->sd_table_name);
522         if (error)
523                 goto fail;
524
525         error = sysfs_create_group(&sdp->sd_kobj, &tune_group);
526         if (error)
527                 goto fail_reg;
528
529         error = sysfs_create_group(&sdp->sd_kobj, &lock_module_group);
530         if (error)
531                 goto fail_tune;
532
533         error = sysfs_create_link(&sdp->sd_kobj,
534                                   &disk_to_dev(sb->s_bdev->bd_disk)->kobj,
535                                   "device");
536         if (error)
537                 goto fail_lock_module;
538
539         kobject_uevent_env(&sdp->sd_kobj, KOBJ_ADD, envp);
540         return 0;
541
542 fail_lock_module:
543         sysfs_remove_group(&sdp->sd_kobj, &lock_module_group);
544 fail_tune:
545         sysfs_remove_group(&sdp->sd_kobj, &tune_group);
546 fail_reg:
547         kobject_put(&sdp->sd_kobj);
548 fail:
549         fs_err(sdp, "error %d adding sysfs files", error);
550         return error;
551 }
552
553 void gfs2_sys_fs_del(struct gfs2_sbd *sdp)
554 {
555         sysfs_remove_link(&sdp->sd_kobj, "device");
556         sysfs_remove_group(&sdp->sd_kobj, &tune_group);
557         sysfs_remove_group(&sdp->sd_kobj, &lock_module_group);
558         kobject_put(&sdp->sd_kobj);
559 }
560
561 static int gfs2_uevent(struct kset *kset, struct kobject *kobj,
562                        struct kobj_uevent_env *env)
563 {
564         struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
565         const u8 *uuid = sdp->sd_sb.sb_uuid;
566
567         add_uevent_var(env, "LOCKTABLE=%s", sdp->sd_table_name);
568         add_uevent_var(env, "LOCKPROTO=%s", sdp->sd_proto_name);
569         if (!sdp->sd_args.ar_spectator)
570                 add_uevent_var(env, "JOURNALID=%u", sdp->sd_lockstruct.ls_jid);
571         if (gfs2_uuid_valid(uuid))
572                 add_uevent_var(env, "UUID=%pUB", uuid);
573         return 0;
574 }
575
576 static const struct kset_uevent_ops gfs2_uevent_ops = {
577         .uevent = gfs2_uevent,
578 };
579
580 int gfs2_sys_init(void)
581 {
582         gfs2_kset = kset_create_and_add("gfs2", &gfs2_uevent_ops, fs_kobj);
583         if (!gfs2_kset)
584                 return -ENOMEM;
585         return 0;
586 }
587
588 void gfs2_sys_uninit(void)
589 {
590         kset_unregister(gfs2_kset);
591 }
592