GFS2: change gfs2_quota_scan into a shrinker
[linux-2.6.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 <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 static ssize_t id_show(struct gfs2_sbd *sdp, char *buf)
30 {
31         return snprintf(buf, PAGE_SIZE, "%u:%u\n",
32                         MAJOR(sdp->sd_vfs->s_dev), MINOR(sdp->sd_vfs->s_dev));
33 }
34
35 static ssize_t fsname_show(struct gfs2_sbd *sdp, char *buf)
36 {
37         return snprintf(buf, PAGE_SIZE, "%s\n", sdp->sd_fsname);
38 }
39
40 static ssize_t freeze_show(struct gfs2_sbd *sdp, char *buf)
41 {
42         unsigned int count;
43
44         mutex_lock(&sdp->sd_freeze_lock);
45         count = sdp->sd_freeze_count;
46         mutex_unlock(&sdp->sd_freeze_lock);
47
48         return snprintf(buf, PAGE_SIZE, "%u\n", count);
49 }
50
51 static ssize_t freeze_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
52 {
53         ssize_t ret = len;
54         int error = 0;
55         int n = simple_strtol(buf, NULL, 0);
56
57         if (!capable(CAP_SYS_ADMIN))
58                 return -EACCES;
59
60         switch (n) {
61         case 0:
62                 gfs2_unfreeze_fs(sdp);
63                 break;
64         case 1:
65                 error = gfs2_freeze_fs(sdp);
66                 break;
67         default:
68                 ret = -EINVAL;
69         }
70
71         if (error)
72                 fs_warn(sdp, "freeze %d error %d", n, error);
73
74         return ret;
75 }
76
77 static ssize_t withdraw_show(struct gfs2_sbd *sdp, char *buf)
78 {
79         unsigned int b = test_bit(SDF_SHUTDOWN, &sdp->sd_flags);
80         return snprintf(buf, PAGE_SIZE, "%u\n", b);
81 }
82
83 static ssize_t withdraw_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
84 {
85         if (!capable(CAP_SYS_ADMIN))
86                 return -EACCES;
87
88         if (simple_strtol(buf, NULL, 0) != 1)
89                 return -EINVAL;
90
91         gfs2_lm_withdraw(sdp,
92                 "GFS2: fsid=%s: withdrawing from cluster at user's request\n",
93                 sdp->sd_fsname);
94         return len;
95 }
96
97 static ssize_t statfs_sync_store(struct gfs2_sbd *sdp, const char *buf,
98                                  size_t len)
99 {
100         if (!capable(CAP_SYS_ADMIN))
101                 return -EACCES;
102
103         if (simple_strtol(buf, NULL, 0) != 1)
104                 return -EINVAL;
105
106         gfs2_statfs_sync(sdp);
107         return len;
108 }
109
110 static ssize_t quota_sync_store(struct gfs2_sbd *sdp, const char *buf,
111                                 size_t len)
112 {
113         if (!capable(CAP_SYS_ADMIN))
114                 return -EACCES;
115
116         if (simple_strtol(buf, NULL, 0) != 1)
117                 return -EINVAL;
118
119         gfs2_quota_sync(sdp);
120         return len;
121 }
122
123 static ssize_t quota_refresh_user_store(struct gfs2_sbd *sdp, const char *buf,
124                                         size_t len)
125 {
126         u32 id;
127
128         if (!capable(CAP_SYS_ADMIN))
129                 return -EACCES;
130
131         id = simple_strtoul(buf, NULL, 0);
132
133         gfs2_quota_refresh(sdp, 1, id);
134         return len;
135 }
136
137 static ssize_t quota_refresh_group_store(struct gfs2_sbd *sdp, const char *buf,
138                                          size_t len)
139 {
140         u32 id;
141
142         if (!capable(CAP_SYS_ADMIN))
143                 return -EACCES;
144
145         id = simple_strtoul(buf, NULL, 0);
146
147         gfs2_quota_refresh(sdp, 0, id);
148         return len;
149 }
150
151 struct gfs2_attr {
152         struct attribute attr;
153         ssize_t (*show)(struct gfs2_sbd *, char *);
154         ssize_t (*store)(struct gfs2_sbd *, const char *, size_t);
155 };
156
157 #define GFS2_ATTR(name, mode, show, store) \
158 static struct gfs2_attr gfs2_attr_##name = __ATTR(name, mode, show, store)
159
160 GFS2_ATTR(id,                  0444, id_show,       NULL);
161 GFS2_ATTR(fsname,              0444, fsname_show,   NULL);
162 GFS2_ATTR(freeze,              0644, freeze_show,   freeze_store);
163 GFS2_ATTR(withdraw,            0644, withdraw_show, withdraw_store);
164 GFS2_ATTR(statfs_sync,         0200, NULL,          statfs_sync_store);
165 GFS2_ATTR(quota_sync,          0200, NULL,          quota_sync_store);
166 GFS2_ATTR(quota_refresh_user,  0200, NULL,          quota_refresh_user_store);
167 GFS2_ATTR(quota_refresh_group, 0200, NULL,          quota_refresh_group_store);
168
169 static struct attribute *gfs2_attrs[] = {
170         &gfs2_attr_id.attr,
171         &gfs2_attr_fsname.attr,
172         &gfs2_attr_freeze.attr,
173         &gfs2_attr_withdraw.attr,
174         &gfs2_attr_statfs_sync.attr,
175         &gfs2_attr_quota_sync.attr,
176         &gfs2_attr_quota_refresh_user.attr,
177         &gfs2_attr_quota_refresh_group.attr,
178         NULL,
179 };
180
181 static ssize_t gfs2_attr_show(struct kobject *kobj, struct attribute *attr,
182                               char *buf)
183 {
184         struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
185         struct gfs2_attr *a = container_of(attr, struct gfs2_attr, attr);
186         return a->show ? a->show(sdp, buf) : 0;
187 }
188
189 static ssize_t gfs2_attr_store(struct kobject *kobj, struct attribute *attr,
190                                const char *buf, size_t len)
191 {
192         struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
193         struct gfs2_attr *a = container_of(attr, struct gfs2_attr, attr);
194         return a->store ? a->store(sdp, buf, len) : len;
195 }
196
197 static struct sysfs_ops gfs2_attr_ops = {
198         .show  = gfs2_attr_show,
199         .store = gfs2_attr_store,
200 };
201
202 static struct kobj_type gfs2_ktype = {
203         .default_attrs = gfs2_attrs,
204         .sysfs_ops     = &gfs2_attr_ops,
205 };
206
207 static struct kset *gfs2_kset;
208
209 /*
210  * display struct lm_lockstruct fields
211  */
212
213 struct lockstruct_attr {
214         struct attribute attr;
215         ssize_t (*show)(struct gfs2_sbd *, char *);
216 };
217
218 #define LOCKSTRUCT_ATTR(name, fmt)                                          \
219 static ssize_t name##_show(struct gfs2_sbd *sdp, char *buf)                 \
220 {                                                                           \
221         return snprintf(buf, PAGE_SIZE, fmt, sdp->sd_lockstruct.ls_##name); \
222 }                                                                           \
223 static struct lockstruct_attr lockstruct_attr_##name = __ATTR_RO(name)
224
225 LOCKSTRUCT_ATTR(jid,      "%u\n");
226 LOCKSTRUCT_ATTR(first,    "%u\n");
227 LOCKSTRUCT_ATTR(lvb_size, "%u\n");
228 LOCKSTRUCT_ATTR(flags,    "%d\n");
229
230 static struct attribute *lockstruct_attrs[] = {
231         &lockstruct_attr_jid.attr,
232         &lockstruct_attr_first.attr,
233         &lockstruct_attr_lvb_size.attr,
234         &lockstruct_attr_flags.attr,
235         NULL,
236 };
237
238 /*
239  * display struct gfs2_args fields
240  */
241
242 struct args_attr {
243         struct attribute attr;
244         ssize_t (*show)(struct gfs2_sbd *, char *);
245 };
246
247 #define ARGS_ATTR(name, fmt)                                                \
248 static ssize_t name##_show(struct gfs2_sbd *sdp, char *buf)                 \
249 {                                                                           \
250         return snprintf(buf, PAGE_SIZE, fmt, sdp->sd_args.ar_##name);       \
251 }                                                                           \
252 static struct args_attr args_attr_##name = __ATTR_RO(name)
253
254 ARGS_ATTR(lockproto,       "%s\n");
255 ARGS_ATTR(locktable,       "%s\n");
256 ARGS_ATTR(hostdata,        "%s\n");
257 ARGS_ATTR(spectator,       "%d\n");
258 ARGS_ATTR(ignore_local_fs, "%d\n");
259 ARGS_ATTR(localcaching,    "%d\n");
260 ARGS_ATTR(localflocks,     "%d\n");
261 ARGS_ATTR(debug,           "%d\n");
262 ARGS_ATTR(upgrade,         "%d\n");
263 ARGS_ATTR(posix_acl,       "%d\n");
264 ARGS_ATTR(quota,           "%u\n");
265 ARGS_ATTR(suiddir,         "%d\n");
266 ARGS_ATTR(data,            "%d\n");
267
268 static struct attribute *args_attrs[] = {
269         &args_attr_lockproto.attr,
270         &args_attr_locktable.attr,
271         &args_attr_hostdata.attr,
272         &args_attr_spectator.attr,
273         &args_attr_ignore_local_fs.attr,
274         &args_attr_localcaching.attr,
275         &args_attr_localflocks.attr,
276         &args_attr_debug.attr,
277         &args_attr_upgrade.attr,
278         &args_attr_posix_acl.attr,
279         &args_attr_quota.attr,
280         &args_attr_suiddir.attr,
281         &args_attr_data.attr,
282         NULL,
283 };
284
285 /*
286  * get and set struct gfs2_tune fields
287  */
288
289 static ssize_t quota_scale_show(struct gfs2_sbd *sdp, char *buf)
290 {
291         return snprintf(buf, PAGE_SIZE, "%u %u\n",
292                         sdp->sd_tune.gt_quota_scale_num,
293                         sdp->sd_tune.gt_quota_scale_den);
294 }
295
296 static ssize_t quota_scale_store(struct gfs2_sbd *sdp, const char *buf,
297                                  size_t len)
298 {
299         struct gfs2_tune *gt = &sdp->sd_tune;
300         unsigned int x, y;
301
302         if (!capable(CAP_SYS_ADMIN))
303                 return -EACCES;
304
305         if (sscanf(buf, "%u %u", &x, &y) != 2 || !y)
306                 return -EINVAL;
307
308         spin_lock(&gt->gt_spin);
309         gt->gt_quota_scale_num = x;
310         gt->gt_quota_scale_den = y;
311         spin_unlock(&gt->gt_spin);
312         return len;
313 }
314
315 static ssize_t tune_set(struct gfs2_sbd *sdp, unsigned int *field,
316                         int check_zero, const char *buf, size_t len)
317 {
318         struct gfs2_tune *gt = &sdp->sd_tune;
319         unsigned int x;
320
321         if (!capable(CAP_SYS_ADMIN))
322                 return -EACCES;
323
324         x = simple_strtoul(buf, NULL, 0);
325
326         if (check_zero && !x)
327                 return -EINVAL;
328
329         spin_lock(&gt->gt_spin);
330         *field = x;
331         spin_unlock(&gt->gt_spin);
332         return len;
333 }
334
335 struct tune_attr {
336         struct attribute attr;
337         ssize_t (*show)(struct gfs2_sbd *, char *);
338         ssize_t (*store)(struct gfs2_sbd *, const char *, size_t);
339 };
340
341 #define TUNE_ATTR_3(name, show, store)                                        \
342 static struct tune_attr tune_attr_##name = __ATTR(name, 0644, show, store)
343
344 #define TUNE_ATTR_2(name, store)                                              \
345 static ssize_t name##_show(struct gfs2_sbd *sdp, char *buf)                   \
346 {                                                                             \
347         return snprintf(buf, PAGE_SIZE, "%u\n", sdp->sd_tune.gt_##name);      \
348 }                                                                             \
349 TUNE_ATTR_3(name, name##_show, store)
350
351 #define TUNE_ATTR(name, check_zero)                                           \
352 static ssize_t name##_store(struct gfs2_sbd *sdp, const char *buf, size_t len)\
353 {                                                                             \
354         return tune_set(sdp, &sdp->sd_tune.gt_##name, check_zero, buf, len);  \
355 }                                                                             \
356 TUNE_ATTR_2(name, name##_store)
357
358 #define TUNE_ATTR_DAEMON(name, process)                                       \
359 static ssize_t name##_store(struct gfs2_sbd *sdp, const char *buf, size_t len)\
360 {                                                                             \
361         ssize_t r = tune_set(sdp, &sdp->sd_tune.gt_##name, 1, buf, len);      \
362         wake_up_process(sdp->sd_##process);                                   \
363         return r;                                                             \
364 }                                                                             \
365 TUNE_ATTR_2(name, name##_store)
366
367 TUNE_ATTR(incore_log_blocks, 0);
368 TUNE_ATTR(log_flush_secs, 0);
369 TUNE_ATTR(quota_warn_period, 0);
370 TUNE_ATTR(quota_quantum, 0);
371 TUNE_ATTR(max_readahead, 0);
372 TUNE_ATTR(complain_secs, 0);
373 TUNE_ATTR(statfs_slow, 0);
374 TUNE_ATTR(new_files_jdata, 0);
375 TUNE_ATTR(quota_simul_sync, 1);
376 TUNE_ATTR(stall_secs, 1);
377 TUNE_ATTR(statfs_quantum, 1);
378 TUNE_ATTR_DAEMON(recoverd_secs, recoverd_process);
379 TUNE_ATTR_DAEMON(logd_secs, logd_process);
380 TUNE_ATTR_3(quota_scale, quota_scale_show, quota_scale_store);
381
382 static struct attribute *tune_attrs[] = {
383         &tune_attr_incore_log_blocks.attr,
384         &tune_attr_log_flush_secs.attr,
385         &tune_attr_quota_warn_period.attr,
386         &tune_attr_quota_quantum.attr,
387         &tune_attr_max_readahead.attr,
388         &tune_attr_complain_secs.attr,
389         &tune_attr_statfs_slow.attr,
390         &tune_attr_quota_simul_sync.attr,
391         &tune_attr_stall_secs.attr,
392         &tune_attr_statfs_quantum.attr,
393         &tune_attr_recoverd_secs.attr,
394         &tune_attr_logd_secs.attr,
395         &tune_attr_quota_scale.attr,
396         &tune_attr_new_files_jdata.attr,
397         NULL,
398 };
399
400 static struct attribute_group lockstruct_group = {
401         .name = "lockstruct",
402         .attrs = lockstruct_attrs,
403 };
404
405 static struct attribute_group args_group = {
406         .name = "args",
407         .attrs = args_attrs,
408 };
409
410 static struct attribute_group tune_group = {
411         .name = "tune",
412         .attrs = tune_attrs,
413 };
414
415 int gfs2_sys_fs_add(struct gfs2_sbd *sdp)
416 {
417         int error;
418
419         sdp->sd_kobj.kset = gfs2_kset;
420         error = kobject_init_and_add(&sdp->sd_kobj, &gfs2_ktype, NULL,
421                                      "%s", sdp->sd_table_name);
422         if (error)
423                 goto fail;
424
425         error = sysfs_create_group(&sdp->sd_kobj, &lockstruct_group);
426         if (error)
427                 goto fail_reg;
428
429         error = sysfs_create_group(&sdp->sd_kobj, &args_group);
430         if (error)
431                 goto fail_lockstruct;
432
433         error = sysfs_create_group(&sdp->sd_kobj, &tune_group);
434         if (error)
435                 goto fail_args;
436
437         kobject_uevent(&sdp->sd_kobj, KOBJ_ADD);
438         return 0;
439
440 fail_args:
441         sysfs_remove_group(&sdp->sd_kobj, &args_group);
442 fail_lockstruct:
443         sysfs_remove_group(&sdp->sd_kobj, &lockstruct_group);
444 fail_reg:
445         kobject_put(&sdp->sd_kobj);
446 fail:
447         fs_err(sdp, "error %d adding sysfs files", error);
448         return error;
449 }
450
451 void gfs2_sys_fs_del(struct gfs2_sbd *sdp)
452 {
453         sysfs_remove_group(&sdp->sd_kobj, &tune_group);
454         sysfs_remove_group(&sdp->sd_kobj, &args_group);
455         sysfs_remove_group(&sdp->sd_kobj, &lockstruct_group);
456         kobject_put(&sdp->sd_kobj);
457 }
458
459 static int gfs2_uevent(struct kset *kset, struct kobject *kobj,
460                        struct kobj_uevent_env *env)
461 {
462         struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
463         add_uevent_var(env, "LOCKTABLE=%s", sdp->sd_table_name);
464         add_uevent_var(env, "LOCKPROTO=%s", sdp->sd_proto_name);
465         return 0;
466 }
467
468 static struct kset_uevent_ops gfs2_uevent_ops = {
469         .uevent = gfs2_uevent,
470 };
471
472
473 int gfs2_sys_init(void)
474 {
475         gfs2_kset = kset_create_and_add("gfs2", &gfs2_uevent_ops, fs_kobj);
476         if (!gfs2_kset)
477                 return -ENOMEM;
478         return 0;
479 }
480
481 void gfs2_sys_uninit(void)
482 {
483         kset_unregister(gfs2_kset);
484 }
485