Merge git://git.infradead.org/embedded-2.6
[linux-2.6] / 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 <linux/gfs2_ondisk.h>
18 #include <linux/lm_interface.h>
19 #include <asm/uaccess.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
29 char *gfs2_sys_margs;
30 spinlock_t gfs2_sys_margs_lock;
31
32 static ssize_t id_show(struct gfs2_sbd *sdp, char *buf)
33 {
34         return snprintf(buf, PAGE_SIZE, "%u:%u\n",
35                         MAJOR(sdp->sd_vfs->s_dev), MINOR(sdp->sd_vfs->s_dev));
36 }
37
38 static ssize_t fsname_show(struct gfs2_sbd *sdp, char *buf)
39 {
40         return snprintf(buf, PAGE_SIZE, "%s\n", sdp->sd_fsname);
41 }
42
43 static ssize_t freeze_show(struct gfs2_sbd *sdp, char *buf)
44 {
45         unsigned int count;
46
47         mutex_lock(&sdp->sd_freeze_lock);
48         count = sdp->sd_freeze_count;
49         mutex_unlock(&sdp->sd_freeze_lock);
50
51         return snprintf(buf, PAGE_SIZE, "%u\n", count);
52 }
53
54 static ssize_t freeze_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
55 {
56         ssize_t ret = len;
57         int error = 0;
58         int n = simple_strtol(buf, NULL, 0);
59
60         if (!capable(CAP_SYS_ADMIN))
61                 return -EACCES;
62
63         switch (n) {
64         case 0:
65                 gfs2_unfreeze_fs(sdp);
66                 break;
67         case 1:
68                 error = gfs2_freeze_fs(sdp);
69                 break;
70         default:
71                 ret = -EINVAL;
72         }
73
74         if (error)
75                 fs_warn(sdp, "freeze %d error %d", n, error);
76
77         return ret;
78 }
79
80 static ssize_t withdraw_show(struct gfs2_sbd *sdp, char *buf)
81 {
82         unsigned int b = test_bit(SDF_SHUTDOWN, &sdp->sd_flags);
83         return snprintf(buf, PAGE_SIZE, "%u\n", b);
84 }
85
86 static ssize_t withdraw_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
87 {
88         if (!capable(CAP_SYS_ADMIN))
89                 return -EACCES;
90
91         if (simple_strtol(buf, NULL, 0) != 1)
92                 return -EINVAL;
93
94         gfs2_lm_withdraw(sdp,
95                 "GFS2: fsid=%s: withdrawing from cluster at user's request\n",
96                 sdp->sd_fsname);
97         return len;
98 }
99
100 static ssize_t statfs_sync_store(struct gfs2_sbd *sdp, const char *buf,
101                                  size_t len)
102 {
103         if (!capable(CAP_SYS_ADMIN))
104                 return -EACCES;
105
106         if (simple_strtol(buf, NULL, 0) != 1)
107                 return -EINVAL;
108
109         gfs2_statfs_sync(sdp);
110         return len;
111 }
112
113 static ssize_t quota_sync_store(struct gfs2_sbd *sdp, const char *buf,
114                                 size_t len)
115 {
116         if (!capable(CAP_SYS_ADMIN))
117                 return -EACCES;
118
119         if (simple_strtol(buf, NULL, 0) != 1)
120                 return -EINVAL;
121
122         gfs2_quota_sync(sdp);
123         return len;
124 }
125
126 static ssize_t quota_refresh_user_store(struct gfs2_sbd *sdp, const char *buf,
127                                         size_t len)
128 {
129         u32 id;
130
131         if (!capable(CAP_SYS_ADMIN))
132                 return -EACCES;
133
134         id = simple_strtoul(buf, NULL, 0);
135
136         gfs2_quota_refresh(sdp, 1, id);
137         return len;
138 }
139
140 static ssize_t quota_refresh_group_store(struct gfs2_sbd *sdp, const char *buf,
141                                          size_t len)
142 {
143         u32 id;
144
145         if (!capable(CAP_SYS_ADMIN))
146                 return -EACCES;
147
148         id = simple_strtoul(buf, NULL, 0);
149
150         gfs2_quota_refresh(sdp, 0, id);
151         return len;
152 }
153
154 struct gfs2_attr {
155         struct attribute attr;
156         ssize_t (*show)(struct gfs2_sbd *, char *);
157         ssize_t (*store)(struct gfs2_sbd *, const char *, size_t);
158 };
159
160 #define GFS2_ATTR(name, mode, show, store) \
161 static struct gfs2_attr gfs2_attr_##name = __ATTR(name, mode, show, store)
162
163 GFS2_ATTR(id,                  0444, id_show,       NULL);
164 GFS2_ATTR(fsname,              0444, fsname_show,   NULL);
165 GFS2_ATTR(freeze,              0644, freeze_show,   freeze_store);
166 GFS2_ATTR(withdraw,            0644, withdraw_show, withdraw_store);
167 GFS2_ATTR(statfs_sync,         0200, NULL,          statfs_sync_store);
168 GFS2_ATTR(quota_sync,          0200, NULL,          quota_sync_store);
169 GFS2_ATTR(quota_refresh_user,  0200, NULL,          quota_refresh_user_store);
170 GFS2_ATTR(quota_refresh_group, 0200, NULL,          quota_refresh_group_store);
171
172 static struct attribute *gfs2_attrs[] = {
173         &gfs2_attr_id.attr,
174         &gfs2_attr_fsname.attr,
175         &gfs2_attr_freeze.attr,
176         &gfs2_attr_withdraw.attr,
177         &gfs2_attr_statfs_sync.attr,
178         &gfs2_attr_quota_sync.attr,
179         &gfs2_attr_quota_refresh_user.attr,
180         &gfs2_attr_quota_refresh_group.attr,
181         NULL,
182 };
183
184 static ssize_t gfs2_attr_show(struct kobject *kobj, struct attribute *attr,
185                               char *buf)
186 {
187         struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
188         struct gfs2_attr *a = container_of(attr, struct gfs2_attr, attr);
189         return a->show ? a->show(sdp, buf) : 0;
190 }
191
192 static ssize_t gfs2_attr_store(struct kobject *kobj, struct attribute *attr,
193                                const char *buf, size_t len)
194 {
195         struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
196         struct gfs2_attr *a = container_of(attr, struct gfs2_attr, attr);
197         return a->store ? a->store(sdp, buf, len) : len;
198 }
199
200 static struct sysfs_ops gfs2_attr_ops = {
201         .show  = gfs2_attr_show,
202         .store = gfs2_attr_store,
203 };
204
205 static struct kobj_type gfs2_ktype = {
206         .default_attrs = gfs2_attrs,
207         .sysfs_ops     = &gfs2_attr_ops,
208 };
209
210 static struct kset *gfs2_kset;
211
212 /*
213  * display struct lm_lockstruct fields
214  */
215
216 struct lockstruct_attr {
217         struct attribute attr;
218         ssize_t (*show)(struct gfs2_sbd *, char *);
219 };
220
221 #define LOCKSTRUCT_ATTR(name, fmt)                                          \
222 static ssize_t name##_show(struct gfs2_sbd *sdp, char *buf)                 \
223 {                                                                           \
224         return snprintf(buf, PAGE_SIZE, fmt, sdp->sd_lockstruct.ls_##name); \
225 }                                                                           \
226 static struct lockstruct_attr lockstruct_attr_##name = __ATTR_RO(name)
227
228 LOCKSTRUCT_ATTR(jid,      "%u\n");
229 LOCKSTRUCT_ATTR(first,    "%u\n");
230 LOCKSTRUCT_ATTR(lvb_size, "%u\n");
231 LOCKSTRUCT_ATTR(flags,    "%d\n");
232
233 static struct attribute *lockstruct_attrs[] = {
234         &lockstruct_attr_jid.attr,
235         &lockstruct_attr_first.attr,
236         &lockstruct_attr_lvb_size.attr,
237         &lockstruct_attr_flags.attr,
238         NULL,
239 };
240
241 /*
242  * display struct gfs2_args fields
243  */
244
245 struct args_attr {
246         struct attribute attr;
247         ssize_t (*show)(struct gfs2_sbd *, char *);
248 };
249
250 #define ARGS_ATTR(name, fmt)                                                \
251 static ssize_t name##_show(struct gfs2_sbd *sdp, char *buf)                 \
252 {                                                                           \
253         return snprintf(buf, PAGE_SIZE, fmt, sdp->sd_args.ar_##name);       \
254 }                                                                           \
255 static struct args_attr args_attr_##name = __ATTR_RO(name)
256
257 ARGS_ATTR(lockproto,       "%s\n");
258 ARGS_ATTR(locktable,       "%s\n");
259 ARGS_ATTR(hostdata,        "%s\n");
260 ARGS_ATTR(spectator,       "%d\n");
261 ARGS_ATTR(ignore_local_fs, "%d\n");
262 ARGS_ATTR(localcaching,    "%d\n");
263 ARGS_ATTR(localflocks,     "%d\n");
264 ARGS_ATTR(debug,           "%d\n");
265 ARGS_ATTR(upgrade,         "%d\n");
266 ARGS_ATTR(num_glockd,      "%u\n");
267 ARGS_ATTR(posix_acl,       "%d\n");
268 ARGS_ATTR(quota,           "%u\n");
269 ARGS_ATTR(suiddir,         "%d\n");
270 ARGS_ATTR(data,            "%d\n");
271
272 /* one oddball doesn't fit the macro mold */
273 static ssize_t noatime_show(struct gfs2_sbd *sdp, char *buf)
274 {
275         return snprintf(buf, PAGE_SIZE, "%d\n",
276                         !!test_bit(SDF_NOATIME, &sdp->sd_flags));
277 }
278 static struct args_attr args_attr_noatime = __ATTR_RO(noatime);
279
280 static struct attribute *args_attrs[] = {
281         &args_attr_lockproto.attr,
282         &args_attr_locktable.attr,
283         &args_attr_hostdata.attr,
284         &args_attr_spectator.attr,
285         &args_attr_ignore_local_fs.attr,
286         &args_attr_localcaching.attr,
287         &args_attr_localflocks.attr,
288         &args_attr_debug.attr,
289         &args_attr_upgrade.attr,
290         &args_attr_num_glockd.attr,
291         &args_attr_posix_acl.attr,
292         &args_attr_quota.attr,
293         &args_attr_suiddir.attr,
294         &args_attr_data.attr,
295         &args_attr_noatime.attr,
296         NULL,
297 };
298
299 /*
300  * display counters from superblock
301  */
302
303 struct counters_attr {
304         struct attribute attr;
305         ssize_t (*show)(struct gfs2_sbd *, char *);
306 };
307
308 #define COUNTERS_ATTR(name, fmt)                                            \
309 static ssize_t name##_show(struct gfs2_sbd *sdp, char *buf)                 \
310 {                                                                           \
311         return snprintf(buf, PAGE_SIZE, fmt,                                \
312                         (unsigned int)atomic_read(&sdp->sd_##name));        \
313 }                                                                           \
314 static struct counters_attr counters_attr_##name = __ATTR_RO(name)
315
316 COUNTERS_ATTR(reclaimed,        "%u\n");
317
318 static struct attribute *counters_attrs[] = {
319         &counters_attr_reclaimed.attr,
320         NULL,
321 };
322
323 /*
324  * get and set struct gfs2_tune fields
325  */
326
327 static ssize_t quota_scale_show(struct gfs2_sbd *sdp, char *buf)
328 {
329         return snprintf(buf, PAGE_SIZE, "%u %u\n",
330                         sdp->sd_tune.gt_quota_scale_num,
331                         sdp->sd_tune.gt_quota_scale_den);
332 }
333
334 static ssize_t quota_scale_store(struct gfs2_sbd *sdp, const char *buf,
335                                  size_t len)
336 {
337         struct gfs2_tune *gt = &sdp->sd_tune;
338         unsigned int x, y;
339
340         if (!capable(CAP_SYS_ADMIN))
341                 return -EACCES;
342
343         if (sscanf(buf, "%u %u", &x, &y) != 2 || !y)
344                 return -EINVAL;
345
346         spin_lock(&gt->gt_spin);
347         gt->gt_quota_scale_num = x;
348         gt->gt_quota_scale_den = y;
349         spin_unlock(&gt->gt_spin);
350         return len;
351 }
352
353 static ssize_t tune_set(struct gfs2_sbd *sdp, unsigned int *field,
354                         int check_zero, const char *buf, size_t len)
355 {
356         struct gfs2_tune *gt = &sdp->sd_tune;
357         unsigned int x;
358
359         if (!capable(CAP_SYS_ADMIN))
360                 return -EACCES;
361
362         x = simple_strtoul(buf, NULL, 0);
363
364         if (check_zero && !x)
365                 return -EINVAL;
366
367         spin_lock(&gt->gt_spin);
368         *field = x;
369         spin_unlock(&gt->gt_spin);
370         return len;
371 }
372
373 struct tune_attr {
374         struct attribute attr;
375         ssize_t (*show)(struct gfs2_sbd *, char *);
376         ssize_t (*store)(struct gfs2_sbd *, const char *, size_t);
377 };
378
379 #define TUNE_ATTR_3(name, show, store)                                        \
380 static struct tune_attr tune_attr_##name = __ATTR(name, 0644, show, store)
381
382 #define TUNE_ATTR_2(name, store)                                              \
383 static ssize_t name##_show(struct gfs2_sbd *sdp, char *buf)                   \
384 {                                                                             \
385         return snprintf(buf, PAGE_SIZE, "%u\n", sdp->sd_tune.gt_##name);      \
386 }                                                                             \
387 TUNE_ATTR_3(name, name##_show, store)
388
389 #define TUNE_ATTR(name, check_zero)                                           \
390 static ssize_t name##_store(struct gfs2_sbd *sdp, const char *buf, size_t len)\
391 {                                                                             \
392         return tune_set(sdp, &sdp->sd_tune.gt_##name, check_zero, buf, len);  \
393 }                                                                             \
394 TUNE_ATTR_2(name, name##_store)
395
396 #define TUNE_ATTR_DAEMON(name, process)                                       \
397 static ssize_t name##_store(struct gfs2_sbd *sdp, const char *buf, size_t len)\
398 {                                                                             \
399         ssize_t r = tune_set(sdp, &sdp->sd_tune.gt_##name, 1, buf, len);      \
400         wake_up_process(sdp->sd_##process);                                   \
401         return r;                                                             \
402 }                                                                             \
403 TUNE_ATTR_2(name, name##_store)
404
405 TUNE_ATTR(demote_secs, 0);
406 TUNE_ATTR(incore_log_blocks, 0);
407 TUNE_ATTR(log_flush_secs, 0);
408 TUNE_ATTR(quota_warn_period, 0);
409 TUNE_ATTR(quota_quantum, 0);
410 TUNE_ATTR(atime_quantum, 0);
411 TUNE_ATTR(max_readahead, 0);
412 TUNE_ATTR(complain_secs, 0);
413 TUNE_ATTR(statfs_slow, 0);
414 TUNE_ATTR(new_files_jdata, 0);
415 TUNE_ATTR(quota_simul_sync, 1);
416 TUNE_ATTR(quota_cache_secs, 1);
417 TUNE_ATTR(stall_secs, 1);
418 TUNE_ATTR(statfs_quantum, 1);
419 TUNE_ATTR_DAEMON(recoverd_secs, recoverd_process);
420 TUNE_ATTR_DAEMON(logd_secs, logd_process);
421 TUNE_ATTR_DAEMON(quotad_secs, quotad_process);
422 TUNE_ATTR_3(quota_scale, quota_scale_show, quota_scale_store);
423
424 static struct attribute *tune_attrs[] = {
425         &tune_attr_demote_secs.attr,
426         &tune_attr_incore_log_blocks.attr,
427         &tune_attr_log_flush_secs.attr,
428         &tune_attr_quota_warn_period.attr,
429         &tune_attr_quota_quantum.attr,
430         &tune_attr_atime_quantum.attr,
431         &tune_attr_max_readahead.attr,
432         &tune_attr_complain_secs.attr,
433         &tune_attr_statfs_slow.attr,
434         &tune_attr_quota_simul_sync.attr,
435         &tune_attr_quota_cache_secs.attr,
436         &tune_attr_stall_secs.attr,
437         &tune_attr_statfs_quantum.attr,
438         &tune_attr_recoverd_secs.attr,
439         &tune_attr_logd_secs.attr,
440         &tune_attr_quotad_secs.attr,
441         &tune_attr_quota_scale.attr,
442         &tune_attr_new_files_jdata.attr,
443         NULL,
444 };
445
446 static struct attribute_group lockstruct_group = {
447         .name = "lockstruct",
448         .attrs = lockstruct_attrs,
449 };
450
451 static struct attribute_group counters_group = {
452         .name = "counters",
453         .attrs = counters_attrs,
454 };
455
456 static struct attribute_group args_group = {
457         .name = "args",
458         .attrs = args_attrs,
459 };
460
461 static struct attribute_group tune_group = {
462         .name = "tune",
463         .attrs = tune_attrs,
464 };
465
466 int gfs2_sys_fs_add(struct gfs2_sbd *sdp)
467 {
468         int error;
469
470         sdp->sd_kobj.kset = gfs2_kset;
471         error = kobject_init_and_add(&sdp->sd_kobj, &gfs2_ktype, NULL,
472                                      "%s", sdp->sd_table_name);
473         if (error)
474                 goto fail;
475
476         error = sysfs_create_group(&sdp->sd_kobj, &lockstruct_group);
477         if (error)
478                 goto fail_reg;
479
480         error = sysfs_create_group(&sdp->sd_kobj, &counters_group);
481         if (error)
482                 goto fail_lockstruct;
483
484         error = sysfs_create_group(&sdp->sd_kobj, &args_group);
485         if (error)
486                 goto fail_counters;
487
488         error = sysfs_create_group(&sdp->sd_kobj, &tune_group);
489         if (error)
490                 goto fail_args;
491
492         kobject_uevent(&sdp->sd_kobj, KOBJ_ADD);
493         return 0;
494
495 fail_args:
496         sysfs_remove_group(&sdp->sd_kobj, &args_group);
497 fail_counters:
498         sysfs_remove_group(&sdp->sd_kobj, &counters_group);
499 fail_lockstruct:
500         sysfs_remove_group(&sdp->sd_kobj, &lockstruct_group);
501 fail_reg:
502         kobject_put(&sdp->sd_kobj);
503 fail:
504         fs_err(sdp, "error %d adding sysfs files", error);
505         return error;
506 }
507
508 void gfs2_sys_fs_del(struct gfs2_sbd *sdp)
509 {
510         sysfs_remove_group(&sdp->sd_kobj, &tune_group);
511         sysfs_remove_group(&sdp->sd_kobj, &args_group);
512         sysfs_remove_group(&sdp->sd_kobj, &counters_group);
513         sysfs_remove_group(&sdp->sd_kobj, &lockstruct_group);
514         kobject_put(&sdp->sd_kobj);
515 }
516
517 int gfs2_sys_init(void)
518 {
519         gfs2_sys_margs = NULL;
520         spin_lock_init(&gfs2_sys_margs_lock);
521         gfs2_kset = kset_create_and_add("gfs2", NULL, fs_kobj);
522         if (!gfs2_kset)
523                 return -ENOMEM;
524         return 0;
525 }
526
527 void gfs2_sys_uninit(void)
528 {
529         kfree(gfs2_sys_margs);
530         kset_unregister(gfs2_kset);
531 }
532