xref: /linux/fs/gfs2/sys.c (revision 6dfafbd0299a60bfb5d5e277fdf100037c7ded07)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
4  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
5  */
6 
7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8 
9 #include <linux/sched.h>
10 #include <linux/cred.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 <linux/uaccess.h>
17 #include <linux/gfs2_ondisk.h>
18 #include <linux/blkdev.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 #include "recovery.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 sysfs_emit(buf, "%u:%u\n",
63 			MAJOR(sdp->sd_vfs->s_dev), MINOR(sdp->sd_vfs->s_dev));
64 }
65 
66 static ssize_t status_show(struct gfs2_sbd *sdp, char *buf)
67 {
68 	unsigned long f = sdp->sd_flags;
69 	ssize_t s;
70 
71 	s = sysfs_emit(buf,
72 		     "Journal Checked:          %d\n"
73 		     "Journal Live:             %d\n"
74 		     "Journal ID:               %d\n"
75 		     "Spectator:                %d\n"
76 		     "Withdrawn:                %d\n"
77 		     "No barriers:              %d\n"
78 		     "No recovery:              %d\n"
79 		     "Demote:                   %d\n"
80 		     "No Journal ID:            %d\n"
81 		     "Mounted RO:               %d\n"
82 		     "RO Recovery:              %d\n"
83 		     "Skip DLM Unlock:          %d\n"
84 		     "Force AIL Flush:          %d\n"
85 		     "FS Freeze Initiator:      %d\n"
86 		     "FS Frozen:                %d\n"
87 		     "Killing:                  %d\n"
88 		     "sd_log_error:             %d\n"
89 		     "sd_log_flush_lock:        %d\n"
90 		     "sd_log_num_revoke:        %u\n"
91 		     "sd_log_in_flight:         %d\n"
92 		     "sd_log_blks_needed:       %d\n"
93 		     "sd_log_blks_free:         %d\n"
94 		     "sd_log_flush_head:        %d\n"
95 		     "sd_log_flush_tail:        %d\n"
96 		     "sd_log_blks_reserved:     %d\n"
97 		     "sd_log_revokes_available: %d\n"
98 		     "sd_log_pinned:            %d\n"
99 		     "sd_log_thresh1:           %d\n"
100 		     "sd_log_thresh2:           %d\n",
101 		     test_bit(SDF_JOURNAL_CHECKED, &f),
102 		     test_bit(SDF_JOURNAL_LIVE, &f),
103 		     (sdp->sd_jdesc ? sdp->sd_jdesc->jd_jid : 0),
104 		     (sdp->sd_args.ar_spectator ? 1 : 0),
105 		     test_bit(SDF_WITHDRAWN, &f),
106 		     test_bit(SDF_NOBARRIERS, &f),
107 		     test_bit(SDF_NORECOVERY, &f),
108 		     test_bit(SDF_DEMOTE, &f),
109 		     test_bit(SDF_NOJOURNALID, &f),
110 		     (sb_rdonly(sdp->sd_vfs) ? 1 : 0),
111 		     test_bit(SDF_RORECOVERY, &f),
112 		     test_bit(SDF_SKIP_DLM_UNLOCK, &f),
113 		     test_bit(SDF_FORCE_AIL_FLUSH, &f),
114 		     test_bit(SDF_FREEZE_INITIATOR, &f),
115 		     test_bit(SDF_FROZEN, &f),
116 		     test_bit(SDF_KILL, &f),
117 		     sdp->sd_log_error,
118 		     rwsem_is_locked(&sdp->sd_log_flush_lock),
119 		     sdp->sd_log_num_revoke,
120 		     atomic_read(&sdp->sd_log_in_flight),
121 		     atomic_read(&sdp->sd_log_blks_needed),
122 		     atomic_read(&sdp->sd_log_blks_free),
123 		     sdp->sd_log_flush_head,
124 		     sdp->sd_log_flush_tail,
125 		     sdp->sd_log_blks_reserved,
126 		     atomic_read(&sdp->sd_log_revokes_available),
127 		     atomic_read(&sdp->sd_log_pinned),
128 		     atomic_read(&sdp->sd_log_thresh1),
129 		     atomic_read(&sdp->sd_log_thresh2));
130 	return s;
131 }
132 
133 static ssize_t fsname_show(struct gfs2_sbd *sdp, char *buf)
134 {
135 	return sysfs_emit(buf, "%s\n", sdp->sd_fsname);
136 }
137 
138 static ssize_t uuid_show(struct gfs2_sbd *sdp, char *buf)
139 {
140 	struct super_block *s = sdp->sd_vfs;
141 
142 	buf[0] = '\0';
143 	if (uuid_is_null(&s->s_uuid))
144 		return 0;
145 	return sysfs_emit(buf, "%pUB\n", &s->s_uuid);
146 }
147 
148 static ssize_t freeze_show(struct gfs2_sbd *sdp, char *buf)
149 {
150 	struct super_block *sb = sdp->sd_vfs;
151 	int frozen = (sb->s_writers.frozen == SB_UNFROZEN) ? 0 : 1;
152 
153 	return sysfs_emit(buf, "%d\n", frozen);
154 }
155 
156 static ssize_t freeze_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
157 {
158 	int error, n;
159 
160 	error = kstrtoint(buf, 0, &n);
161 	if (error)
162 		return error;
163 
164 	if (!capable(CAP_SYS_ADMIN))
165 		return -EPERM;
166 
167 	switch (n) {
168 	case 0:
169 		error = thaw_super(sdp->sd_vfs, FREEZE_HOLDER_USERSPACE, NULL);
170 		break;
171 	case 1:
172 		error = freeze_super(sdp->sd_vfs, FREEZE_HOLDER_USERSPACE, NULL);
173 		break;
174 	default:
175 		return -EINVAL;
176 	}
177 
178 	if (error) {
179 		fs_warn(sdp, "freeze %d error %d\n", n, error);
180 		return error;
181 	}
182 
183 	return len;
184 }
185 
186 static ssize_t withdraw_show(struct gfs2_sbd *sdp, char *buf)
187 {
188 	unsigned int b = gfs2_withdrawn(sdp);
189 	return sysfs_emit(buf, "%u\n", b);
190 }
191 
192 static ssize_t withdraw_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
193 {
194 	int error, val;
195 
196 	if (!capable(CAP_SYS_ADMIN))
197 		return -EPERM;
198 
199 	error = kstrtoint(buf, 0, &val);
200 	if (error)
201 		return error;
202 
203 	if (val != 1)
204 		return -EINVAL;
205 
206 	gfs2_lm(sdp, "withdrawing from cluster at user's request\n");
207 	gfs2_withdraw(sdp);
208 
209 	return len;
210 }
211 
212 static ssize_t statfs_sync_store(struct gfs2_sbd *sdp, const char *buf,
213 				 size_t len)
214 {
215 	int error, val;
216 
217 	if (!capable(CAP_SYS_ADMIN))
218 		return -EPERM;
219 
220 	error = kstrtoint(buf, 0, &val);
221 	if (error)
222 		return error;
223 
224 	if (val != 1)
225 		return -EINVAL;
226 
227 	gfs2_statfs_sync(sdp->sd_vfs, 0);
228 	return len;
229 }
230 
231 static ssize_t quota_sync_store(struct gfs2_sbd *sdp, const char *buf,
232 				size_t len)
233 {
234 	int error, val;
235 
236 	if (!capable(CAP_SYS_ADMIN))
237 		return -EPERM;
238 
239 	error = kstrtoint(buf, 0, &val);
240 	if (error)
241 		return error;
242 
243 	if (val != 1)
244 		return -EINVAL;
245 
246 	gfs2_quota_sync(sdp->sd_vfs, 0);
247 	return len;
248 }
249 
250 static ssize_t quota_refresh_user_store(struct gfs2_sbd *sdp, const char *buf,
251 					size_t len)
252 {
253 	struct kqid qid;
254 	int error;
255 	u32 id;
256 
257 	if (!capable(CAP_SYS_ADMIN))
258 		return -EPERM;
259 
260 	error = kstrtou32(buf, 0, &id);
261 	if (error)
262 		return error;
263 
264 	qid = make_kqid(current_user_ns(), USRQUOTA, id);
265 	if (!qid_valid(qid))
266 		return -EINVAL;
267 
268 	error = gfs2_quota_refresh(sdp, qid);
269 	return error ? error : len;
270 }
271 
272 static ssize_t quota_refresh_group_store(struct gfs2_sbd *sdp, const char *buf,
273 					 size_t len)
274 {
275 	struct kqid qid;
276 	int error;
277 	u32 id;
278 
279 	if (!capable(CAP_SYS_ADMIN))
280 		return -EPERM;
281 
282 	error = kstrtou32(buf, 0, &id);
283 	if (error)
284 		return error;
285 
286 	qid = make_kqid(current_user_ns(), GRPQUOTA, id);
287 	if (!qid_valid(qid))
288 		return -EINVAL;
289 
290 	error = gfs2_quota_refresh(sdp, qid);
291 	return error ? error : len;
292 }
293 
294 static ssize_t demote_rq_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
295 {
296 	struct gfs2_glock *gl;
297 	const struct gfs2_glock_operations *glops;
298 	unsigned int glmode;
299 	unsigned int gltype;
300 	unsigned long long glnum;
301 	char mode[16];
302 	int rv;
303 
304 	if (!capable(CAP_SYS_ADMIN))
305 		return -EPERM;
306 
307 	rv = sscanf(buf, "%u:%llu %15s", &gltype, &glnum,
308 		    mode);
309 	if (rv != 3)
310 		return -EINVAL;
311 
312 	if (strcmp(mode, "EX") == 0)
313 		glmode = LM_ST_UNLOCKED;
314 	else if ((strcmp(mode, "CW") == 0) || (strcmp(mode, "DF") == 0))
315 		glmode = LM_ST_DEFERRED;
316 	else if ((strcmp(mode, "PR") == 0) || (strcmp(mode, "SH") == 0))
317 		glmode = LM_ST_SHARED;
318 	else
319 		return -EINVAL;
320 
321 	if (gltype > LM_TYPE_JOURNAL)
322 		return -EINVAL;
323 	if (gltype == LM_TYPE_NONDISK && glnum == GFS2_FREEZE_LOCK)
324 		glops = &gfs2_freeze_glops;
325 	else
326 		glops = gfs2_glops_list[gltype];
327 	if (glops == NULL)
328 		return -EINVAL;
329 	if (!test_and_set_bit(SDF_DEMOTE, &sdp->sd_flags))
330 		fs_info(sdp, "demote interface used\n");
331 	rv = gfs2_glock_get(sdp, glnum, glops, NO_CREATE, &gl);
332 	if (rv)
333 		return rv;
334 	gfs2_glock_cb(gl, glmode);
335 	gfs2_glock_put(gl);
336 	return len;
337 }
338 
339 
340 #define GFS2_ATTR(name, mode, show, store) \
341 static struct gfs2_attr gfs2_attr_##name = __ATTR(name, mode, show, store)
342 
343 GFS2_ATTR(id,                  0444, id_show,       NULL);
344 GFS2_ATTR(fsname,              0444, fsname_show,   NULL);
345 GFS2_ATTR(uuid,                0444, uuid_show,     NULL);
346 GFS2_ATTR(freeze,              0644, freeze_show,   freeze_store);
347 GFS2_ATTR(withdraw,            0644, withdraw_show, withdraw_store);
348 GFS2_ATTR(statfs_sync,         0200, NULL,          statfs_sync_store);
349 GFS2_ATTR(quota_sync,          0200, NULL,          quota_sync_store);
350 GFS2_ATTR(quota_refresh_user,  0200, NULL,          quota_refresh_user_store);
351 GFS2_ATTR(quota_refresh_group, 0200, NULL,          quota_refresh_group_store);
352 GFS2_ATTR(demote_rq,           0200, NULL,	    demote_rq_store);
353 GFS2_ATTR(status,              0400, status_show,   NULL);
354 
355 static struct attribute *gfs2_attrs[] = {
356 	&gfs2_attr_id.attr,
357 	&gfs2_attr_fsname.attr,
358 	&gfs2_attr_uuid.attr,
359 	&gfs2_attr_freeze.attr,
360 	&gfs2_attr_withdraw.attr,
361 	&gfs2_attr_statfs_sync.attr,
362 	&gfs2_attr_quota_sync.attr,
363 	&gfs2_attr_quota_refresh_user.attr,
364 	&gfs2_attr_quota_refresh_group.attr,
365 	&gfs2_attr_demote_rq.attr,
366 	&gfs2_attr_status.attr,
367 	NULL,
368 };
369 ATTRIBUTE_GROUPS(gfs2);
370 
371 static void gfs2_sbd_release(struct kobject *kobj)
372 {
373 	struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
374 
375 	complete(&sdp->sd_kobj_unregister);
376 }
377 
378 static struct kobj_type gfs2_ktype = {
379 	.release = gfs2_sbd_release,
380 	.default_groups = gfs2_groups,
381 	.sysfs_ops     = &gfs2_attr_ops,
382 };
383 
384 
385 /*
386  * lock_module. Originally from lock_dlm
387  */
388 
389 static ssize_t proto_name_show(struct gfs2_sbd *sdp, char *buf)
390 {
391 	const struct lm_lockops *ops = sdp->sd_lockstruct.ls_ops;
392 	return sysfs_emit(buf, "%s\n", ops->lm_proto_name);
393 }
394 
395 static ssize_t block_show(struct gfs2_sbd *sdp, char *buf)
396 {
397 	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
398 	ssize_t ret;
399 	int val = 0;
400 
401 	if (test_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags))
402 		val = 1;
403 	ret = sysfs_emit(buf, "%d\n", val);
404 	return ret;
405 }
406 
407 static ssize_t block_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
408 {
409 	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
410 	int ret, val;
411 
412 	ret = kstrtoint(buf, 0, &val);
413 	if (ret)
414 		return ret;
415 
416 	if (val == 1)
417 		set_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags);
418 	else if (val == 0) {
419 		clear_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags);
420 		smp_mb__after_atomic();
421 		gfs2_glock_thaw(sdp);
422 	} else {
423 		return -EINVAL;
424 	}
425 	return len;
426 }
427 
428 static ssize_t withdraw_helper_status_store(struct gfs2_sbd *sdp,
429 					    const char *buf,
430 					    size_t len)
431 {
432 	int ret, val;
433 
434 	ret = kstrtoint(buf, 0, &val);
435 	if (ret)
436 		return ret;
437 	if (val < 0 || val > 1)
438 		return -EINVAL;
439 
440 	sdp->sd_withdraw_helper_status = val;
441 	complete(&sdp->sd_withdraw_helper);
442 	return len;
443 }
444 
445 static ssize_t lkfirst_show(struct gfs2_sbd *sdp, char *buf)
446 {
447 	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
448 	return sysfs_emit(buf, "%d\n", ls->ls_first);
449 }
450 
451 static ssize_t lkfirst_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
452 {
453 	unsigned first;
454 	int rv;
455 
456 	rv = sscanf(buf, "%u", &first);
457 	if (rv != 1 || first > 1)
458 		return -EINVAL;
459 	rv = wait_for_completion_killable(&sdp->sd_locking_init);
460 	if (rv)
461 		return rv;
462 	spin_lock(&sdp->sd_jindex_spin);
463 	rv = -EBUSY;
464 	if (test_bit(SDF_NOJOURNALID, &sdp->sd_flags) == 0)
465 		goto out;
466 	rv = -EINVAL;
467 	if (sdp->sd_args.ar_spectator)
468 		goto out;
469 	if (sdp->sd_lockstruct.ls_ops->lm_mount == NULL)
470 		goto out;
471 	sdp->sd_lockstruct.ls_first = first;
472 	rv = 0;
473 out:
474         spin_unlock(&sdp->sd_jindex_spin);
475         return rv ? rv : len;
476 }
477 
478 static ssize_t first_done_show(struct gfs2_sbd *sdp, char *buf)
479 {
480 	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
481 	return sysfs_emit(buf, "%d\n", !!test_bit(DFL_FIRST_MOUNT_DONE, &ls->ls_recover_flags));
482 }
483 
484 int gfs2_recover_set(struct gfs2_sbd *sdp, unsigned jid)
485 {
486 	struct gfs2_jdesc *jd;
487 	int rv;
488 
489 	/* Wait for our primary journal to be initialized */
490 	wait_for_completion(&sdp->sd_journal_ready);
491 
492 	spin_lock(&sdp->sd_jindex_spin);
493 	rv = -EBUSY;
494 	/**
495 	 * If we're a spectator, we use journal0, but it's not really ours.
496 	 * So we need to wait for its recovery too. If we skip it we'd never
497 	 * queue work to the recovery workqueue, and so its completion would
498 	 * never clear the DFL_BLOCK_LOCKS flag, so all our locks would
499 	 * permanently stop working.
500 	 */
501 	if (!sdp->sd_jdesc)
502 		goto out;
503 	if (sdp->sd_jdesc->jd_jid == jid && !sdp->sd_args.ar_spectator)
504 		goto out;
505 	rv = -ENOENT;
506 	list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
507 		if (jd->jd_jid != jid && !sdp->sd_args.ar_spectator)
508 			continue;
509 		rv = gfs2_recover_journal(jd, false);
510 		break;
511 	}
512 out:
513 	spin_unlock(&sdp->sd_jindex_spin);
514 	return rv;
515 }
516 
517 static ssize_t recover_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
518 {
519 	unsigned jid;
520 	int rv;
521 
522 	rv = sscanf(buf, "%u", &jid);
523 	if (rv != 1)
524 		return -EINVAL;
525 
526 	if (test_bit(SDF_NORECOVERY, &sdp->sd_flags)) {
527 		rv = -ESHUTDOWN;
528 		goto out;
529 	}
530 
531 	rv = gfs2_recover_set(sdp, jid);
532 out:
533 	return rv ? rv : len;
534 }
535 
536 static ssize_t recover_done_show(struct gfs2_sbd *sdp, char *buf)
537 {
538 	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
539 	return sysfs_emit(buf, "%d\n", ls->ls_recover_jid_done);
540 }
541 
542 static ssize_t recover_status_show(struct gfs2_sbd *sdp, char *buf)
543 {
544 	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
545 	return sysfs_emit(buf, "%d\n", ls->ls_recover_jid_status);
546 }
547 
548 static ssize_t jid_show(struct gfs2_sbd *sdp, char *buf)
549 {
550 	return sysfs_emit(buf, "%d\n", sdp->sd_lockstruct.ls_jid);
551 }
552 
553 static ssize_t jid_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
554 {
555         int jid;
556 	int rv;
557 
558 	rv = sscanf(buf, "%d", &jid);
559 	if (rv != 1)
560 		return -EINVAL;
561 	rv = wait_for_completion_killable(&sdp->sd_locking_init);
562 	if (rv)
563 		return rv;
564 	spin_lock(&sdp->sd_jindex_spin);
565 	rv = -EINVAL;
566 	if (sdp->sd_lockstruct.ls_ops->lm_mount == NULL)
567 		goto out;
568 	rv = -EBUSY;
569 	if (test_bit(SDF_NOJOURNALID, &sdp->sd_flags) == 0)
570 		goto out;
571 	rv = 0;
572 	if (sdp->sd_args.ar_spectator && jid > 0)
573 		rv = jid = -EINVAL;
574 	sdp->sd_lockstruct.ls_jid = jid;
575 	clear_bit(SDF_NOJOURNALID, &sdp->sd_flags);
576 	smp_mb__after_atomic();
577 	wake_up_bit(&sdp->sd_flags, SDF_NOJOURNALID);
578 out:
579 	spin_unlock(&sdp->sd_jindex_spin);
580 	return rv ? rv : len;
581 }
582 
583 #define GDLM_ATTR(_name,_mode,_show,_store) \
584 static struct gfs2_attr gdlm_attr_##_name = __ATTR(_name,_mode,_show,_store)
585 
586 GDLM_ATTR(proto_name,		0444, proto_name_show,		NULL);
587 GDLM_ATTR(block,		0644, block_show,		block_store);
588 GDLM_ATTR(withdraw,		0200, NULL,			withdraw_helper_status_store);
589 GDLM_ATTR(jid,			0644, jid_show,			jid_store);
590 GDLM_ATTR(first,		0644, lkfirst_show,		lkfirst_store);
591 GDLM_ATTR(first_done,		0444, first_done_show,		NULL);
592 GDLM_ATTR(recover,		0600, NULL,			recover_store);
593 GDLM_ATTR(recover_done,		0444, recover_done_show,	NULL);
594 GDLM_ATTR(recover_status,	0444, recover_status_show,	NULL);
595 
596 static struct attribute *lock_module_attrs[] = {
597 	&gdlm_attr_proto_name.attr,
598 	&gdlm_attr_block.attr,
599 	&gdlm_attr_withdraw.attr,
600 	&gdlm_attr_jid.attr,
601 	&gdlm_attr_first.attr,
602 	&gdlm_attr_first_done.attr,
603 	&gdlm_attr_recover.attr,
604 	&gdlm_attr_recover_done.attr,
605 	&gdlm_attr_recover_status.attr,
606 	NULL,
607 };
608 
609 /*
610  * get and set struct gfs2_tune fields
611  */
612 
613 static ssize_t quota_scale_show(struct gfs2_sbd *sdp, char *buf)
614 {
615 	return sysfs_emit(buf, "%u %u\n",
616 			sdp->sd_tune.gt_quota_scale_num,
617 			sdp->sd_tune.gt_quota_scale_den);
618 }
619 
620 static ssize_t quota_scale_store(struct gfs2_sbd *sdp, const char *buf,
621 				 size_t len)
622 {
623 	struct gfs2_tune *gt = &sdp->sd_tune;
624 	unsigned int x, y;
625 
626 	if (!capable(CAP_SYS_ADMIN))
627 		return -EPERM;
628 
629 	if (sscanf(buf, "%u %u", &x, &y) != 2 || !y)
630 		return -EINVAL;
631 
632 	spin_lock(&gt->gt_spin);
633 	gt->gt_quota_scale_num = x;
634 	gt->gt_quota_scale_den = y;
635 	spin_unlock(&gt->gt_spin);
636 	return len;
637 }
638 
639 static ssize_t tune_set(struct gfs2_sbd *sdp, unsigned int *field,
640 			int check_zero, const char *buf, size_t len)
641 {
642 	struct gfs2_tune *gt = &sdp->sd_tune;
643 	unsigned int x;
644 	int error;
645 
646 	if (!capable(CAP_SYS_ADMIN))
647 		return -EPERM;
648 
649 	error = kstrtouint(buf, 0, &x);
650 	if (error)
651 		return error;
652 
653 	if (check_zero && !x)
654 		return -EINVAL;
655 
656 	spin_lock(&gt->gt_spin);
657 	*field = x;
658 	spin_unlock(&gt->gt_spin);
659 	return len;
660 }
661 
662 #define TUNE_ATTR_3(name, show, store)                                        \
663 static struct gfs2_attr tune_attr_##name = __ATTR(name, 0644, show, store)
664 
665 #define TUNE_ATTR_2(name, store)                                              \
666 static ssize_t name##_show(struct gfs2_sbd *sdp, char *buf)                   \
667 {                                                                             \
668 	return sysfs_emit(buf, "%u\n", sdp->sd_tune.gt_##name);               \
669 }                                                                             \
670 TUNE_ATTR_3(name, name##_show, store)
671 
672 #define TUNE_ATTR(name, check_zero)                                           \
673 static ssize_t name##_store(struct gfs2_sbd *sdp, const char *buf, size_t len)\
674 {                                                                             \
675 	return tune_set(sdp, &sdp->sd_tune.gt_##name, check_zero, buf, len);  \
676 }                                                                             \
677 TUNE_ATTR_2(name, name##_store)
678 
679 TUNE_ATTR(quota_warn_period, 0);
680 TUNE_ATTR(quota_quantum, 0);
681 TUNE_ATTR(max_readahead, 0);
682 TUNE_ATTR(complain_secs, 0);
683 TUNE_ATTR(statfs_slow, 0);
684 TUNE_ATTR(new_files_jdata, 0);
685 TUNE_ATTR(statfs_quantum, 1);
686 TUNE_ATTR_3(quota_scale, quota_scale_show, quota_scale_store);
687 TUNE_ATTR(withdraw_helper_timeout, 1);
688 
689 static struct attribute *tune_attrs[] = {
690 	&tune_attr_quota_warn_period.attr,
691 	&tune_attr_quota_quantum.attr,
692 	&tune_attr_max_readahead.attr,
693 	&tune_attr_complain_secs.attr,
694 	&tune_attr_statfs_slow.attr,
695 	&tune_attr_statfs_quantum.attr,
696 	&tune_attr_quota_scale.attr,
697 	&tune_attr_new_files_jdata.attr,
698 	&tune_attr_withdraw_helper_timeout.attr,
699 	NULL,
700 };
701 
702 static const struct attribute_group tune_group = {
703 	.name = "tune",
704 	.attrs = tune_attrs,
705 };
706 
707 static const struct attribute_group lock_module_group = {
708 	.name = "lock_module",
709 	.attrs = lock_module_attrs,
710 };
711 
712 int gfs2_sys_fs_add(struct gfs2_sbd *sdp)
713 {
714 	struct super_block *sb = sdp->sd_vfs;
715 	int error;
716 	char ro[20];
717 	char spectator[20];
718 	char *envp[] = { ro, spectator, NULL };
719 
720 	sprintf(ro, "RDONLY=%d", sb_rdonly(sb));
721 	sprintf(spectator, "SPECTATOR=%d", sdp->sd_args.ar_spectator ? 1 : 0);
722 
723 	init_completion(&sdp->sd_kobj_unregister);
724 	sdp->sd_kobj.kset = gfs2_kset;
725 	error = kobject_init_and_add(&sdp->sd_kobj, &gfs2_ktype, NULL,
726 				     "%s", sdp->sd_table_name);
727 	if (error)
728 		goto fail_reg;
729 
730 	error = sysfs_create_group(&sdp->sd_kobj, &tune_group);
731 	if (error)
732 		goto fail_reg;
733 
734 	error = sysfs_create_group(&sdp->sd_kobj, &lock_module_group);
735 	if (error)
736 		goto fail_tune;
737 
738 	error = sysfs_create_link(&sdp->sd_kobj,
739 				  &disk_to_dev(sb->s_bdev->bd_disk)->kobj,
740 				  "device");
741 	if (error)
742 		goto fail_lock_module;
743 
744 	kobject_uevent_env(&sdp->sd_kobj, KOBJ_ADD, envp);
745 	return 0;
746 
747 fail_lock_module:
748 	sysfs_remove_group(&sdp->sd_kobj, &lock_module_group);
749 fail_tune:
750 	sysfs_remove_group(&sdp->sd_kobj, &tune_group);
751 fail_reg:
752 	fs_err(sdp, "error %d adding sysfs files\n", error);
753 	kobject_put(&sdp->sd_kobj);
754 	wait_for_completion(&sdp->sd_kobj_unregister);
755 	return error;
756 }
757 
758 void gfs2_sys_fs_del(struct gfs2_sbd *sdp)
759 {
760 	sysfs_remove_link(&sdp->sd_kobj, "device");
761 	sysfs_remove_group(&sdp->sd_kobj, &tune_group);
762 	sysfs_remove_group(&sdp->sd_kobj, &lock_module_group);
763 	kobject_put(&sdp->sd_kobj);
764 	wait_for_completion(&sdp->sd_kobj_unregister);
765 }
766 
767 static int gfs2_uevent(const struct kobject *kobj, struct kobj_uevent_env *env)
768 {
769 	const struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
770 	const struct super_block *s = sdp->sd_vfs;
771 
772 	add_uevent_var(env, "LOCKTABLE=%s", sdp->sd_table_name);
773 	add_uevent_var(env, "LOCKPROTO=%s", sdp->sd_proto_name);
774 	if (!test_bit(SDF_NOJOURNALID, &sdp->sd_flags))
775 		add_uevent_var(env, "JOURNALID=%d", sdp->sd_lockstruct.ls_jid);
776 	if (!uuid_is_null(&s->s_uuid))
777 		add_uevent_var(env, "UUID=%pUB", &s->s_uuid);
778 	return 0;
779 }
780 
781 static const struct kset_uevent_ops gfs2_uevent_ops = {
782 	.uevent = gfs2_uevent,
783 };
784 
785 int gfs2_sys_init(void)
786 {
787 	gfs2_kset = kset_create_and_add("gfs2", &gfs2_uevent_ops, fs_kobj);
788 	if (!gfs2_kset)
789 		return -ENOMEM;
790 	return 0;
791 }
792 
793 void gfs2_sys_uninit(void)
794 {
795 	kset_unregister(gfs2_kset);
796 }
797 
798