xref: /linux/fs/nilfs2/sysfs.c (revision 2da68a77)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Sysfs support implementation.
4  *
5  * Copyright (C) 2005-2014 Nippon Telegraph and Telephone Corporation.
6  * Copyright (C) 2014 HGST, Inc., a Western Digital Company.
7  *
8  * Written by Vyacheslav Dubeyko <Vyacheslav.Dubeyko@hgst.com>
9  */
10 
11 #include <linux/kobject.h>
12 
13 #include "nilfs.h"
14 #include "mdt.h"
15 #include "sufile.h"
16 #include "cpfile.h"
17 #include "sysfs.h"
18 
19 /* /sys/fs/<nilfs>/ */
20 static struct kset *nilfs_kset;
21 
22 #define NILFS_DEV_INT_GROUP_OPS(name, parent_name) \
23 static ssize_t nilfs_##name##_attr_show(struct kobject *kobj, \
24 					struct attribute *attr, char *buf) \
25 { \
26 	struct the_nilfs *nilfs = container_of(kobj->parent, \
27 						struct the_nilfs, \
28 						ns_##parent_name##_kobj); \
29 	struct nilfs_##name##_attr *a = container_of(attr, \
30 						struct nilfs_##name##_attr, \
31 						attr); \
32 	return a->show ? a->show(a, nilfs, buf) : 0; \
33 } \
34 static ssize_t nilfs_##name##_attr_store(struct kobject *kobj, \
35 					 struct attribute *attr, \
36 					 const char *buf, size_t len) \
37 { \
38 	struct the_nilfs *nilfs = container_of(kobj->parent, \
39 						struct the_nilfs, \
40 						ns_##parent_name##_kobj); \
41 	struct nilfs_##name##_attr *a = container_of(attr, \
42 						struct nilfs_##name##_attr, \
43 						attr); \
44 	return a->store ? a->store(a, nilfs, buf, len) : 0; \
45 } \
46 static const struct sysfs_ops nilfs_##name##_attr_ops = { \
47 	.show	= nilfs_##name##_attr_show, \
48 	.store	= nilfs_##name##_attr_store, \
49 }
50 
51 #define NILFS_DEV_INT_GROUP_TYPE(name, parent_name) \
52 static void nilfs_##name##_attr_release(struct kobject *kobj) \
53 { \
54 	struct nilfs_sysfs_##parent_name##_subgroups *subgroups = container_of(kobj, \
55 						struct nilfs_sysfs_##parent_name##_subgroups, \
56 						sg_##name##_kobj); \
57 	complete(&subgroups->sg_##name##_kobj_unregister); \
58 } \
59 static struct kobj_type nilfs_##name##_ktype = { \
60 	.default_groups	= nilfs_##name##_groups, \
61 	.sysfs_ops	= &nilfs_##name##_attr_ops, \
62 	.release	= nilfs_##name##_attr_release, \
63 }
64 
65 #define NILFS_DEV_INT_GROUP_FNS(name, parent_name) \
66 static int nilfs_sysfs_create_##name##_group(struct the_nilfs *nilfs) \
67 { \
68 	struct kobject *parent; \
69 	struct kobject *kobj; \
70 	struct completion *kobj_unregister; \
71 	struct nilfs_sysfs_##parent_name##_subgroups *subgroups; \
72 	int err; \
73 	subgroups = nilfs->ns_##parent_name##_subgroups; \
74 	kobj = &subgroups->sg_##name##_kobj; \
75 	kobj_unregister = &subgroups->sg_##name##_kobj_unregister; \
76 	parent = &nilfs->ns_##parent_name##_kobj; \
77 	kobj->kset = nilfs_kset; \
78 	init_completion(kobj_unregister); \
79 	err = kobject_init_and_add(kobj, &nilfs_##name##_ktype, parent, \
80 				    #name); \
81 	if (err) \
82 		kobject_put(kobj); \
83 	return err; \
84 } \
85 static void nilfs_sysfs_delete_##name##_group(struct the_nilfs *nilfs) \
86 { \
87 	kobject_put(&nilfs->ns_##parent_name##_subgroups->sg_##name##_kobj); \
88 }
89 
90 /************************************************************************
91  *                        NILFS snapshot attrs                          *
92  ************************************************************************/
93 
94 static ssize_t
95 nilfs_snapshot_inodes_count_show(struct nilfs_snapshot_attr *attr,
96 				 struct nilfs_root *root, char *buf)
97 {
98 	return sysfs_emit(buf, "%llu\n",
99 			(unsigned long long)atomic64_read(&root->inodes_count));
100 }
101 
102 static ssize_t
103 nilfs_snapshot_blocks_count_show(struct nilfs_snapshot_attr *attr,
104 				 struct nilfs_root *root, char *buf)
105 {
106 	return sysfs_emit(buf, "%llu\n",
107 			(unsigned long long)atomic64_read(&root->blocks_count));
108 }
109 
110 static const char snapshot_readme_str[] =
111 	"The group contains details about mounted snapshot.\n\n"
112 	"(1) inodes_count\n\tshow number of inodes for snapshot.\n\n"
113 	"(2) blocks_count\n\tshow number of blocks for snapshot.\n\n";
114 
115 static ssize_t
116 nilfs_snapshot_README_show(struct nilfs_snapshot_attr *attr,
117 			    struct nilfs_root *root, char *buf)
118 {
119 	return sysfs_emit(buf, snapshot_readme_str);
120 }
121 
122 NILFS_SNAPSHOT_RO_ATTR(inodes_count);
123 NILFS_SNAPSHOT_RO_ATTR(blocks_count);
124 NILFS_SNAPSHOT_RO_ATTR(README);
125 
126 static struct attribute *nilfs_snapshot_attrs[] = {
127 	NILFS_SNAPSHOT_ATTR_LIST(inodes_count),
128 	NILFS_SNAPSHOT_ATTR_LIST(blocks_count),
129 	NILFS_SNAPSHOT_ATTR_LIST(README),
130 	NULL,
131 };
132 ATTRIBUTE_GROUPS(nilfs_snapshot);
133 
134 static ssize_t nilfs_snapshot_attr_show(struct kobject *kobj,
135 					struct attribute *attr, char *buf)
136 {
137 	struct nilfs_root *root =
138 			container_of(kobj, struct nilfs_root, snapshot_kobj);
139 	struct nilfs_snapshot_attr *a =
140 			container_of(attr, struct nilfs_snapshot_attr, attr);
141 
142 	return a->show ? a->show(a, root, buf) : 0;
143 }
144 
145 static ssize_t nilfs_snapshot_attr_store(struct kobject *kobj,
146 					 struct attribute *attr,
147 					 const char *buf, size_t len)
148 {
149 	struct nilfs_root *root =
150 			container_of(kobj, struct nilfs_root, snapshot_kobj);
151 	struct nilfs_snapshot_attr *a =
152 			container_of(attr, struct nilfs_snapshot_attr, attr);
153 
154 	return a->store ? a->store(a, root, buf, len) : 0;
155 }
156 
157 static void nilfs_snapshot_attr_release(struct kobject *kobj)
158 {
159 	struct nilfs_root *root = container_of(kobj, struct nilfs_root,
160 						snapshot_kobj);
161 	complete(&root->snapshot_kobj_unregister);
162 }
163 
164 static const struct sysfs_ops nilfs_snapshot_attr_ops = {
165 	.show	= nilfs_snapshot_attr_show,
166 	.store	= nilfs_snapshot_attr_store,
167 };
168 
169 static struct kobj_type nilfs_snapshot_ktype = {
170 	.default_groups	= nilfs_snapshot_groups,
171 	.sysfs_ops	= &nilfs_snapshot_attr_ops,
172 	.release	= nilfs_snapshot_attr_release,
173 };
174 
175 int nilfs_sysfs_create_snapshot_group(struct nilfs_root *root)
176 {
177 	struct the_nilfs *nilfs;
178 	struct kobject *parent;
179 	int err;
180 
181 	nilfs = root->nilfs;
182 	parent = &nilfs->ns_dev_subgroups->sg_mounted_snapshots_kobj;
183 	root->snapshot_kobj.kset = nilfs_kset;
184 	init_completion(&root->snapshot_kobj_unregister);
185 
186 	if (root->cno == NILFS_CPTREE_CURRENT_CNO) {
187 		err = kobject_init_and_add(&root->snapshot_kobj,
188 					    &nilfs_snapshot_ktype,
189 					    &nilfs->ns_dev_kobj,
190 					    "current_checkpoint");
191 	} else {
192 		err = kobject_init_and_add(&root->snapshot_kobj,
193 					    &nilfs_snapshot_ktype,
194 					    parent,
195 					    "%llu", root->cno);
196 	}
197 
198 	if (err)
199 		kobject_put(&root->snapshot_kobj);
200 
201 	return err;
202 }
203 
204 void nilfs_sysfs_delete_snapshot_group(struct nilfs_root *root)
205 {
206 	kobject_put(&root->snapshot_kobj);
207 }
208 
209 /************************************************************************
210  *                    NILFS mounted snapshots attrs                     *
211  ************************************************************************/
212 
213 static const char mounted_snapshots_readme_str[] =
214 	"The mounted_snapshots group contains group for\n"
215 	"every mounted snapshot.\n";
216 
217 static ssize_t
218 nilfs_mounted_snapshots_README_show(struct nilfs_mounted_snapshots_attr *attr,
219 				    struct the_nilfs *nilfs, char *buf)
220 {
221 	return sysfs_emit(buf, mounted_snapshots_readme_str);
222 }
223 
224 NILFS_MOUNTED_SNAPSHOTS_RO_ATTR(README);
225 
226 static struct attribute *nilfs_mounted_snapshots_attrs[] = {
227 	NILFS_MOUNTED_SNAPSHOTS_ATTR_LIST(README),
228 	NULL,
229 };
230 ATTRIBUTE_GROUPS(nilfs_mounted_snapshots);
231 
232 NILFS_DEV_INT_GROUP_OPS(mounted_snapshots, dev);
233 NILFS_DEV_INT_GROUP_TYPE(mounted_snapshots, dev);
234 NILFS_DEV_INT_GROUP_FNS(mounted_snapshots, dev);
235 
236 /************************************************************************
237  *                      NILFS checkpoints attrs                         *
238  ************************************************************************/
239 
240 static ssize_t
241 nilfs_checkpoints_checkpoints_number_show(struct nilfs_checkpoints_attr *attr,
242 					    struct the_nilfs *nilfs,
243 					    char *buf)
244 {
245 	__u64 ncheckpoints;
246 	struct nilfs_cpstat cpstat;
247 	int err;
248 
249 	down_read(&nilfs->ns_segctor_sem);
250 	err = nilfs_cpfile_get_stat(nilfs->ns_cpfile, &cpstat);
251 	up_read(&nilfs->ns_segctor_sem);
252 	if (err < 0) {
253 		nilfs_err(nilfs->ns_sb, "unable to get checkpoint stat: err=%d",
254 			  err);
255 		return err;
256 	}
257 
258 	ncheckpoints = cpstat.cs_ncps;
259 
260 	return sysfs_emit(buf, "%llu\n", ncheckpoints);
261 }
262 
263 static ssize_t
264 nilfs_checkpoints_snapshots_number_show(struct nilfs_checkpoints_attr *attr,
265 					struct the_nilfs *nilfs,
266 					char *buf)
267 {
268 	__u64 nsnapshots;
269 	struct nilfs_cpstat cpstat;
270 	int err;
271 
272 	down_read(&nilfs->ns_segctor_sem);
273 	err = nilfs_cpfile_get_stat(nilfs->ns_cpfile, &cpstat);
274 	up_read(&nilfs->ns_segctor_sem);
275 	if (err < 0) {
276 		nilfs_err(nilfs->ns_sb, "unable to get checkpoint stat: err=%d",
277 			  err);
278 		return err;
279 	}
280 
281 	nsnapshots = cpstat.cs_nsss;
282 
283 	return sysfs_emit(buf, "%llu\n", nsnapshots);
284 }
285 
286 static ssize_t
287 nilfs_checkpoints_last_seg_checkpoint_show(struct nilfs_checkpoints_attr *attr,
288 					    struct the_nilfs *nilfs,
289 					    char *buf)
290 {
291 	__u64 last_cno;
292 
293 	spin_lock(&nilfs->ns_last_segment_lock);
294 	last_cno = nilfs->ns_last_cno;
295 	spin_unlock(&nilfs->ns_last_segment_lock);
296 
297 	return sysfs_emit(buf, "%llu\n", last_cno);
298 }
299 
300 static ssize_t
301 nilfs_checkpoints_next_checkpoint_show(struct nilfs_checkpoints_attr *attr,
302 					struct the_nilfs *nilfs,
303 					char *buf)
304 {
305 	__u64 cno;
306 
307 	down_read(&nilfs->ns_segctor_sem);
308 	cno = nilfs->ns_cno;
309 	up_read(&nilfs->ns_segctor_sem);
310 
311 	return sysfs_emit(buf, "%llu\n", cno);
312 }
313 
314 static const char checkpoints_readme_str[] =
315 	"The checkpoints group contains attributes that describe\n"
316 	"details about volume's checkpoints.\n\n"
317 	"(1) checkpoints_number\n\tshow number of checkpoints on volume.\n\n"
318 	"(2) snapshots_number\n\tshow number of snapshots on volume.\n\n"
319 	"(3) last_seg_checkpoint\n"
320 	"\tshow checkpoint number of the latest segment.\n\n"
321 	"(4) next_checkpoint\n\tshow next checkpoint number.\n\n";
322 
323 static ssize_t
324 nilfs_checkpoints_README_show(struct nilfs_checkpoints_attr *attr,
325 				struct the_nilfs *nilfs, char *buf)
326 {
327 	return sysfs_emit(buf, checkpoints_readme_str);
328 }
329 
330 NILFS_CHECKPOINTS_RO_ATTR(checkpoints_number);
331 NILFS_CHECKPOINTS_RO_ATTR(snapshots_number);
332 NILFS_CHECKPOINTS_RO_ATTR(last_seg_checkpoint);
333 NILFS_CHECKPOINTS_RO_ATTR(next_checkpoint);
334 NILFS_CHECKPOINTS_RO_ATTR(README);
335 
336 static struct attribute *nilfs_checkpoints_attrs[] = {
337 	NILFS_CHECKPOINTS_ATTR_LIST(checkpoints_number),
338 	NILFS_CHECKPOINTS_ATTR_LIST(snapshots_number),
339 	NILFS_CHECKPOINTS_ATTR_LIST(last_seg_checkpoint),
340 	NILFS_CHECKPOINTS_ATTR_LIST(next_checkpoint),
341 	NILFS_CHECKPOINTS_ATTR_LIST(README),
342 	NULL,
343 };
344 ATTRIBUTE_GROUPS(nilfs_checkpoints);
345 
346 NILFS_DEV_INT_GROUP_OPS(checkpoints, dev);
347 NILFS_DEV_INT_GROUP_TYPE(checkpoints, dev);
348 NILFS_DEV_INT_GROUP_FNS(checkpoints, dev);
349 
350 /************************************************************************
351  *                        NILFS segments attrs                          *
352  ************************************************************************/
353 
354 static ssize_t
355 nilfs_segments_segments_number_show(struct nilfs_segments_attr *attr,
356 				     struct the_nilfs *nilfs,
357 				     char *buf)
358 {
359 	return sysfs_emit(buf, "%lu\n", nilfs->ns_nsegments);
360 }
361 
362 static ssize_t
363 nilfs_segments_blocks_per_segment_show(struct nilfs_segments_attr *attr,
364 					struct the_nilfs *nilfs,
365 					char *buf)
366 {
367 	return sysfs_emit(buf, "%lu\n", nilfs->ns_blocks_per_segment);
368 }
369 
370 static ssize_t
371 nilfs_segments_clean_segments_show(struct nilfs_segments_attr *attr,
372 				    struct the_nilfs *nilfs,
373 				    char *buf)
374 {
375 	unsigned long ncleansegs;
376 
377 	down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
378 	ncleansegs = nilfs_sufile_get_ncleansegs(nilfs->ns_sufile);
379 	up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
380 
381 	return sysfs_emit(buf, "%lu\n", ncleansegs);
382 }
383 
384 static ssize_t
385 nilfs_segments_dirty_segments_show(struct nilfs_segments_attr *attr,
386 				    struct the_nilfs *nilfs,
387 				    char *buf)
388 {
389 	struct nilfs_sustat sustat;
390 	int err;
391 
392 	down_read(&nilfs->ns_segctor_sem);
393 	err = nilfs_sufile_get_stat(nilfs->ns_sufile, &sustat);
394 	up_read(&nilfs->ns_segctor_sem);
395 	if (err < 0) {
396 		nilfs_err(nilfs->ns_sb, "unable to get segment stat: err=%d",
397 			  err);
398 		return err;
399 	}
400 
401 	return sysfs_emit(buf, "%llu\n", sustat.ss_ndirtysegs);
402 }
403 
404 static const char segments_readme_str[] =
405 	"The segments group contains attributes that describe\n"
406 	"details about volume's segments.\n\n"
407 	"(1) segments_number\n\tshow number of segments on volume.\n\n"
408 	"(2) blocks_per_segment\n\tshow number of blocks in segment.\n\n"
409 	"(3) clean_segments\n\tshow count of clean segments.\n\n"
410 	"(4) dirty_segments\n\tshow count of dirty segments.\n\n";
411 
412 static ssize_t
413 nilfs_segments_README_show(struct nilfs_segments_attr *attr,
414 			    struct the_nilfs *nilfs,
415 			    char *buf)
416 {
417 	return sysfs_emit(buf, segments_readme_str);
418 }
419 
420 NILFS_SEGMENTS_RO_ATTR(segments_number);
421 NILFS_SEGMENTS_RO_ATTR(blocks_per_segment);
422 NILFS_SEGMENTS_RO_ATTR(clean_segments);
423 NILFS_SEGMENTS_RO_ATTR(dirty_segments);
424 NILFS_SEGMENTS_RO_ATTR(README);
425 
426 static struct attribute *nilfs_segments_attrs[] = {
427 	NILFS_SEGMENTS_ATTR_LIST(segments_number),
428 	NILFS_SEGMENTS_ATTR_LIST(blocks_per_segment),
429 	NILFS_SEGMENTS_ATTR_LIST(clean_segments),
430 	NILFS_SEGMENTS_ATTR_LIST(dirty_segments),
431 	NILFS_SEGMENTS_ATTR_LIST(README),
432 	NULL,
433 };
434 ATTRIBUTE_GROUPS(nilfs_segments);
435 
436 NILFS_DEV_INT_GROUP_OPS(segments, dev);
437 NILFS_DEV_INT_GROUP_TYPE(segments, dev);
438 NILFS_DEV_INT_GROUP_FNS(segments, dev);
439 
440 /************************************************************************
441  *                        NILFS segctor attrs                           *
442  ************************************************************************/
443 
444 static ssize_t
445 nilfs_segctor_last_pseg_block_show(struct nilfs_segctor_attr *attr,
446 				    struct the_nilfs *nilfs,
447 				    char *buf)
448 {
449 	sector_t last_pseg;
450 
451 	spin_lock(&nilfs->ns_last_segment_lock);
452 	last_pseg = nilfs->ns_last_pseg;
453 	spin_unlock(&nilfs->ns_last_segment_lock);
454 
455 	return sysfs_emit(buf, "%llu\n",
456 			(unsigned long long)last_pseg);
457 }
458 
459 static ssize_t
460 nilfs_segctor_last_seg_sequence_show(struct nilfs_segctor_attr *attr,
461 					struct the_nilfs *nilfs,
462 					char *buf)
463 {
464 	u64 last_seq;
465 
466 	spin_lock(&nilfs->ns_last_segment_lock);
467 	last_seq = nilfs->ns_last_seq;
468 	spin_unlock(&nilfs->ns_last_segment_lock);
469 
470 	return sysfs_emit(buf, "%llu\n", last_seq);
471 }
472 
473 static ssize_t
474 nilfs_segctor_last_seg_checkpoint_show(struct nilfs_segctor_attr *attr,
475 					struct the_nilfs *nilfs,
476 					char *buf)
477 {
478 	__u64 last_cno;
479 
480 	spin_lock(&nilfs->ns_last_segment_lock);
481 	last_cno = nilfs->ns_last_cno;
482 	spin_unlock(&nilfs->ns_last_segment_lock);
483 
484 	return sysfs_emit(buf, "%llu\n", last_cno);
485 }
486 
487 static ssize_t
488 nilfs_segctor_current_seg_sequence_show(struct nilfs_segctor_attr *attr,
489 					struct the_nilfs *nilfs,
490 					char *buf)
491 {
492 	u64 seg_seq;
493 
494 	down_read(&nilfs->ns_segctor_sem);
495 	seg_seq = nilfs->ns_seg_seq;
496 	up_read(&nilfs->ns_segctor_sem);
497 
498 	return sysfs_emit(buf, "%llu\n", seg_seq);
499 }
500 
501 static ssize_t
502 nilfs_segctor_current_last_full_seg_show(struct nilfs_segctor_attr *attr,
503 					 struct the_nilfs *nilfs,
504 					 char *buf)
505 {
506 	__u64 segnum;
507 
508 	down_read(&nilfs->ns_segctor_sem);
509 	segnum = nilfs->ns_segnum;
510 	up_read(&nilfs->ns_segctor_sem);
511 
512 	return sysfs_emit(buf, "%llu\n", segnum);
513 }
514 
515 static ssize_t
516 nilfs_segctor_next_full_seg_show(struct nilfs_segctor_attr *attr,
517 				 struct the_nilfs *nilfs,
518 				 char *buf)
519 {
520 	__u64 nextnum;
521 
522 	down_read(&nilfs->ns_segctor_sem);
523 	nextnum = nilfs->ns_nextnum;
524 	up_read(&nilfs->ns_segctor_sem);
525 
526 	return sysfs_emit(buf, "%llu\n", nextnum);
527 }
528 
529 static ssize_t
530 nilfs_segctor_next_pseg_offset_show(struct nilfs_segctor_attr *attr,
531 					struct the_nilfs *nilfs,
532 					char *buf)
533 {
534 	unsigned long pseg_offset;
535 
536 	down_read(&nilfs->ns_segctor_sem);
537 	pseg_offset = nilfs->ns_pseg_offset;
538 	up_read(&nilfs->ns_segctor_sem);
539 
540 	return sysfs_emit(buf, "%lu\n", pseg_offset);
541 }
542 
543 static ssize_t
544 nilfs_segctor_next_checkpoint_show(struct nilfs_segctor_attr *attr,
545 					struct the_nilfs *nilfs,
546 					char *buf)
547 {
548 	__u64 cno;
549 
550 	down_read(&nilfs->ns_segctor_sem);
551 	cno = nilfs->ns_cno;
552 	up_read(&nilfs->ns_segctor_sem);
553 
554 	return sysfs_emit(buf, "%llu\n", cno);
555 }
556 
557 static ssize_t
558 nilfs_segctor_last_seg_write_time_show(struct nilfs_segctor_attr *attr,
559 					struct the_nilfs *nilfs,
560 					char *buf)
561 {
562 	time64_t ctime;
563 
564 	down_read(&nilfs->ns_segctor_sem);
565 	ctime = nilfs->ns_ctime;
566 	up_read(&nilfs->ns_segctor_sem);
567 
568 	return sysfs_emit(buf, "%ptTs\n", &ctime);
569 }
570 
571 static ssize_t
572 nilfs_segctor_last_seg_write_time_secs_show(struct nilfs_segctor_attr *attr,
573 					    struct the_nilfs *nilfs,
574 					    char *buf)
575 {
576 	time64_t ctime;
577 
578 	down_read(&nilfs->ns_segctor_sem);
579 	ctime = nilfs->ns_ctime;
580 	up_read(&nilfs->ns_segctor_sem);
581 
582 	return sysfs_emit(buf, "%llu\n", ctime);
583 }
584 
585 static ssize_t
586 nilfs_segctor_last_nongc_write_time_show(struct nilfs_segctor_attr *attr,
587 					 struct the_nilfs *nilfs,
588 					 char *buf)
589 {
590 	time64_t nongc_ctime;
591 
592 	down_read(&nilfs->ns_segctor_sem);
593 	nongc_ctime = nilfs->ns_nongc_ctime;
594 	up_read(&nilfs->ns_segctor_sem);
595 
596 	return sysfs_emit(buf, "%ptTs\n", &nongc_ctime);
597 }
598 
599 static ssize_t
600 nilfs_segctor_last_nongc_write_time_secs_show(struct nilfs_segctor_attr *attr,
601 						struct the_nilfs *nilfs,
602 						char *buf)
603 {
604 	time64_t nongc_ctime;
605 
606 	down_read(&nilfs->ns_segctor_sem);
607 	nongc_ctime = nilfs->ns_nongc_ctime;
608 	up_read(&nilfs->ns_segctor_sem);
609 
610 	return sysfs_emit(buf, "%llu\n", nongc_ctime);
611 }
612 
613 static ssize_t
614 nilfs_segctor_dirty_data_blocks_count_show(struct nilfs_segctor_attr *attr,
615 					    struct the_nilfs *nilfs,
616 					    char *buf)
617 {
618 	u32 ndirtyblks;
619 
620 	down_read(&nilfs->ns_segctor_sem);
621 	ndirtyblks = atomic_read(&nilfs->ns_ndirtyblks);
622 	up_read(&nilfs->ns_segctor_sem);
623 
624 	return sysfs_emit(buf, "%u\n", ndirtyblks);
625 }
626 
627 static const char segctor_readme_str[] =
628 	"The segctor group contains attributes that describe\n"
629 	"segctor thread activity details.\n\n"
630 	"(1) last_pseg_block\n"
631 	"\tshow start block number of the latest segment.\n\n"
632 	"(2) last_seg_sequence\n"
633 	"\tshow sequence value of the latest segment.\n\n"
634 	"(3) last_seg_checkpoint\n"
635 	"\tshow checkpoint number of the latest segment.\n\n"
636 	"(4) current_seg_sequence\n\tshow segment sequence counter.\n\n"
637 	"(5) current_last_full_seg\n"
638 	"\tshow index number of the latest full segment.\n\n"
639 	"(6) next_full_seg\n"
640 	"\tshow index number of the full segment index to be used next.\n\n"
641 	"(7) next_pseg_offset\n"
642 	"\tshow offset of next partial segment in the current full segment.\n\n"
643 	"(8) next_checkpoint\n\tshow next checkpoint number.\n\n"
644 	"(9) last_seg_write_time\n"
645 	"\tshow write time of the last segment in human-readable format.\n\n"
646 	"(10) last_seg_write_time_secs\n"
647 	"\tshow write time of the last segment in seconds.\n\n"
648 	"(11) last_nongc_write_time\n"
649 	"\tshow write time of the last segment not for cleaner operation "
650 	"in human-readable format.\n\n"
651 	"(12) last_nongc_write_time_secs\n"
652 	"\tshow write time of the last segment not for cleaner operation "
653 	"in seconds.\n\n"
654 	"(13) dirty_data_blocks_count\n"
655 	"\tshow number of dirty data blocks.\n\n";
656 
657 static ssize_t
658 nilfs_segctor_README_show(struct nilfs_segctor_attr *attr,
659 			  struct the_nilfs *nilfs, char *buf)
660 {
661 	return sysfs_emit(buf, segctor_readme_str);
662 }
663 
664 NILFS_SEGCTOR_RO_ATTR(last_pseg_block);
665 NILFS_SEGCTOR_RO_ATTR(last_seg_sequence);
666 NILFS_SEGCTOR_RO_ATTR(last_seg_checkpoint);
667 NILFS_SEGCTOR_RO_ATTR(current_seg_sequence);
668 NILFS_SEGCTOR_RO_ATTR(current_last_full_seg);
669 NILFS_SEGCTOR_RO_ATTR(next_full_seg);
670 NILFS_SEGCTOR_RO_ATTR(next_pseg_offset);
671 NILFS_SEGCTOR_RO_ATTR(next_checkpoint);
672 NILFS_SEGCTOR_RO_ATTR(last_seg_write_time);
673 NILFS_SEGCTOR_RO_ATTR(last_seg_write_time_secs);
674 NILFS_SEGCTOR_RO_ATTR(last_nongc_write_time);
675 NILFS_SEGCTOR_RO_ATTR(last_nongc_write_time_secs);
676 NILFS_SEGCTOR_RO_ATTR(dirty_data_blocks_count);
677 NILFS_SEGCTOR_RO_ATTR(README);
678 
679 static struct attribute *nilfs_segctor_attrs[] = {
680 	NILFS_SEGCTOR_ATTR_LIST(last_pseg_block),
681 	NILFS_SEGCTOR_ATTR_LIST(last_seg_sequence),
682 	NILFS_SEGCTOR_ATTR_LIST(last_seg_checkpoint),
683 	NILFS_SEGCTOR_ATTR_LIST(current_seg_sequence),
684 	NILFS_SEGCTOR_ATTR_LIST(current_last_full_seg),
685 	NILFS_SEGCTOR_ATTR_LIST(next_full_seg),
686 	NILFS_SEGCTOR_ATTR_LIST(next_pseg_offset),
687 	NILFS_SEGCTOR_ATTR_LIST(next_checkpoint),
688 	NILFS_SEGCTOR_ATTR_LIST(last_seg_write_time),
689 	NILFS_SEGCTOR_ATTR_LIST(last_seg_write_time_secs),
690 	NILFS_SEGCTOR_ATTR_LIST(last_nongc_write_time),
691 	NILFS_SEGCTOR_ATTR_LIST(last_nongc_write_time_secs),
692 	NILFS_SEGCTOR_ATTR_LIST(dirty_data_blocks_count),
693 	NILFS_SEGCTOR_ATTR_LIST(README),
694 	NULL,
695 };
696 ATTRIBUTE_GROUPS(nilfs_segctor);
697 
698 NILFS_DEV_INT_GROUP_OPS(segctor, dev);
699 NILFS_DEV_INT_GROUP_TYPE(segctor, dev);
700 NILFS_DEV_INT_GROUP_FNS(segctor, dev);
701 
702 /************************************************************************
703  *                        NILFS superblock attrs                        *
704  ************************************************************************/
705 
706 static ssize_t
707 nilfs_superblock_sb_write_time_show(struct nilfs_superblock_attr *attr,
708 				     struct the_nilfs *nilfs,
709 				     char *buf)
710 {
711 	time64_t sbwtime;
712 
713 	down_read(&nilfs->ns_sem);
714 	sbwtime = nilfs->ns_sbwtime;
715 	up_read(&nilfs->ns_sem);
716 
717 	return sysfs_emit(buf, "%ptTs\n", &sbwtime);
718 }
719 
720 static ssize_t
721 nilfs_superblock_sb_write_time_secs_show(struct nilfs_superblock_attr *attr,
722 					 struct the_nilfs *nilfs,
723 					 char *buf)
724 {
725 	time64_t sbwtime;
726 
727 	down_read(&nilfs->ns_sem);
728 	sbwtime = nilfs->ns_sbwtime;
729 	up_read(&nilfs->ns_sem);
730 
731 	return sysfs_emit(buf, "%llu\n", sbwtime);
732 }
733 
734 static ssize_t
735 nilfs_superblock_sb_write_count_show(struct nilfs_superblock_attr *attr,
736 				      struct the_nilfs *nilfs,
737 				      char *buf)
738 {
739 	unsigned int sbwcount;
740 
741 	down_read(&nilfs->ns_sem);
742 	sbwcount = nilfs->ns_sbwcount;
743 	up_read(&nilfs->ns_sem);
744 
745 	return sysfs_emit(buf, "%u\n", sbwcount);
746 }
747 
748 static ssize_t
749 nilfs_superblock_sb_update_frequency_show(struct nilfs_superblock_attr *attr,
750 					    struct the_nilfs *nilfs,
751 					    char *buf)
752 {
753 	unsigned int sb_update_freq;
754 
755 	down_read(&nilfs->ns_sem);
756 	sb_update_freq = nilfs->ns_sb_update_freq;
757 	up_read(&nilfs->ns_sem);
758 
759 	return sysfs_emit(buf, "%u\n", sb_update_freq);
760 }
761 
762 static ssize_t
763 nilfs_superblock_sb_update_frequency_store(struct nilfs_superblock_attr *attr,
764 					    struct the_nilfs *nilfs,
765 					    const char *buf, size_t count)
766 {
767 	unsigned int val;
768 	int err;
769 
770 	err = kstrtouint(skip_spaces(buf), 0, &val);
771 	if (err) {
772 		nilfs_err(nilfs->ns_sb, "unable to convert string: err=%d",
773 			  err);
774 		return err;
775 	}
776 
777 	if (val < NILFS_SB_FREQ) {
778 		val = NILFS_SB_FREQ;
779 		nilfs_warn(nilfs->ns_sb,
780 			   "superblock update frequency cannot be lesser than 10 seconds");
781 	}
782 
783 	down_write(&nilfs->ns_sem);
784 	nilfs->ns_sb_update_freq = val;
785 	up_write(&nilfs->ns_sem);
786 
787 	return count;
788 }
789 
790 static const char sb_readme_str[] =
791 	"The superblock group contains attributes that describe\n"
792 	"superblock's details.\n\n"
793 	"(1) sb_write_time\n\tshow previous write time of super block "
794 	"in human-readable format.\n\n"
795 	"(2) sb_write_time_secs\n\tshow previous write time of super block "
796 	"in seconds.\n\n"
797 	"(3) sb_write_count\n\tshow write count of super block.\n\n"
798 	"(4) sb_update_frequency\n"
799 	"\tshow/set interval of periodical update of superblock (in seconds).\n\n"
800 	"\tYou can set preferable frequency of superblock update by command:\n\n"
801 	"\t'echo <val> > /sys/fs/<nilfs>/<dev>/superblock/sb_update_frequency'\n";
802 
803 static ssize_t
804 nilfs_superblock_README_show(struct nilfs_superblock_attr *attr,
805 				struct the_nilfs *nilfs, char *buf)
806 {
807 	return sysfs_emit(buf, sb_readme_str);
808 }
809 
810 NILFS_SUPERBLOCK_RO_ATTR(sb_write_time);
811 NILFS_SUPERBLOCK_RO_ATTR(sb_write_time_secs);
812 NILFS_SUPERBLOCK_RO_ATTR(sb_write_count);
813 NILFS_SUPERBLOCK_RW_ATTR(sb_update_frequency);
814 NILFS_SUPERBLOCK_RO_ATTR(README);
815 
816 static struct attribute *nilfs_superblock_attrs[] = {
817 	NILFS_SUPERBLOCK_ATTR_LIST(sb_write_time),
818 	NILFS_SUPERBLOCK_ATTR_LIST(sb_write_time_secs),
819 	NILFS_SUPERBLOCK_ATTR_LIST(sb_write_count),
820 	NILFS_SUPERBLOCK_ATTR_LIST(sb_update_frequency),
821 	NILFS_SUPERBLOCK_ATTR_LIST(README),
822 	NULL,
823 };
824 ATTRIBUTE_GROUPS(nilfs_superblock);
825 
826 NILFS_DEV_INT_GROUP_OPS(superblock, dev);
827 NILFS_DEV_INT_GROUP_TYPE(superblock, dev);
828 NILFS_DEV_INT_GROUP_FNS(superblock, dev);
829 
830 /************************************************************************
831  *                        NILFS device attrs                            *
832  ************************************************************************/
833 
834 static
835 ssize_t nilfs_dev_revision_show(struct nilfs_dev_attr *attr,
836 				struct the_nilfs *nilfs,
837 				char *buf)
838 {
839 	struct nilfs_super_block **sbp = nilfs->ns_sbp;
840 	u32 major = le32_to_cpu(sbp[0]->s_rev_level);
841 	u16 minor = le16_to_cpu(sbp[0]->s_minor_rev_level);
842 
843 	return sysfs_emit(buf, "%d.%d\n", major, minor);
844 }
845 
846 static
847 ssize_t nilfs_dev_blocksize_show(struct nilfs_dev_attr *attr,
848 				 struct the_nilfs *nilfs,
849 				 char *buf)
850 {
851 	return sysfs_emit(buf, "%u\n", nilfs->ns_blocksize);
852 }
853 
854 static
855 ssize_t nilfs_dev_device_size_show(struct nilfs_dev_attr *attr,
856 				    struct the_nilfs *nilfs,
857 				    char *buf)
858 {
859 	struct nilfs_super_block **sbp = nilfs->ns_sbp;
860 	u64 dev_size = le64_to_cpu(sbp[0]->s_dev_size);
861 
862 	return sysfs_emit(buf, "%llu\n", dev_size);
863 }
864 
865 static
866 ssize_t nilfs_dev_free_blocks_show(struct nilfs_dev_attr *attr,
867 				   struct the_nilfs *nilfs,
868 				   char *buf)
869 {
870 	sector_t free_blocks = 0;
871 
872 	nilfs_count_free_blocks(nilfs, &free_blocks);
873 	return sysfs_emit(buf, "%llu\n",
874 			(unsigned long long)free_blocks);
875 }
876 
877 static
878 ssize_t nilfs_dev_uuid_show(struct nilfs_dev_attr *attr,
879 			    struct the_nilfs *nilfs,
880 			    char *buf)
881 {
882 	struct nilfs_super_block **sbp = nilfs->ns_sbp;
883 
884 	return sysfs_emit(buf, "%pUb\n", sbp[0]->s_uuid);
885 }
886 
887 static
888 ssize_t nilfs_dev_volume_name_show(struct nilfs_dev_attr *attr,
889 				    struct the_nilfs *nilfs,
890 				    char *buf)
891 {
892 	struct nilfs_super_block **sbp = nilfs->ns_sbp;
893 
894 	return scnprintf(buf, sizeof(sbp[0]->s_volume_name), "%s\n",
895 			 sbp[0]->s_volume_name);
896 }
897 
898 static const char dev_readme_str[] =
899 	"The <device> group contains attributes that describe file system\n"
900 	"partition's details.\n\n"
901 	"(1) revision\n\tshow NILFS file system revision.\n\n"
902 	"(2) blocksize\n\tshow volume block size in bytes.\n\n"
903 	"(3) device_size\n\tshow volume size in bytes.\n\n"
904 	"(4) free_blocks\n\tshow count of free blocks on volume.\n\n"
905 	"(5) uuid\n\tshow volume's UUID.\n\n"
906 	"(6) volume_name\n\tshow volume's name.\n\n";
907 
908 static ssize_t nilfs_dev_README_show(struct nilfs_dev_attr *attr,
909 				     struct the_nilfs *nilfs,
910 				     char *buf)
911 {
912 	return sysfs_emit(buf, dev_readme_str);
913 }
914 
915 NILFS_DEV_RO_ATTR(revision);
916 NILFS_DEV_RO_ATTR(blocksize);
917 NILFS_DEV_RO_ATTR(device_size);
918 NILFS_DEV_RO_ATTR(free_blocks);
919 NILFS_DEV_RO_ATTR(uuid);
920 NILFS_DEV_RO_ATTR(volume_name);
921 NILFS_DEV_RO_ATTR(README);
922 
923 static struct attribute *nilfs_dev_attrs[] = {
924 	NILFS_DEV_ATTR_LIST(revision),
925 	NILFS_DEV_ATTR_LIST(blocksize),
926 	NILFS_DEV_ATTR_LIST(device_size),
927 	NILFS_DEV_ATTR_LIST(free_blocks),
928 	NILFS_DEV_ATTR_LIST(uuid),
929 	NILFS_DEV_ATTR_LIST(volume_name),
930 	NILFS_DEV_ATTR_LIST(README),
931 	NULL,
932 };
933 ATTRIBUTE_GROUPS(nilfs_dev);
934 
935 static ssize_t nilfs_dev_attr_show(struct kobject *kobj,
936 				    struct attribute *attr, char *buf)
937 {
938 	struct the_nilfs *nilfs = container_of(kobj, struct the_nilfs,
939 						ns_dev_kobj);
940 	struct nilfs_dev_attr *a = container_of(attr, struct nilfs_dev_attr,
941 						attr);
942 
943 	return a->show ? a->show(a, nilfs, buf) : 0;
944 }
945 
946 static ssize_t nilfs_dev_attr_store(struct kobject *kobj,
947 				    struct attribute *attr,
948 				    const char *buf, size_t len)
949 {
950 	struct the_nilfs *nilfs = container_of(kobj, struct the_nilfs,
951 						ns_dev_kobj);
952 	struct nilfs_dev_attr *a = container_of(attr, struct nilfs_dev_attr,
953 						attr);
954 
955 	return a->store ? a->store(a, nilfs, buf, len) : 0;
956 }
957 
958 static void nilfs_dev_attr_release(struct kobject *kobj)
959 {
960 	struct the_nilfs *nilfs = container_of(kobj, struct the_nilfs,
961 						ns_dev_kobj);
962 	complete(&nilfs->ns_dev_kobj_unregister);
963 }
964 
965 static const struct sysfs_ops nilfs_dev_attr_ops = {
966 	.show	= nilfs_dev_attr_show,
967 	.store	= nilfs_dev_attr_store,
968 };
969 
970 static struct kobj_type nilfs_dev_ktype = {
971 	.default_groups	= nilfs_dev_groups,
972 	.sysfs_ops	= &nilfs_dev_attr_ops,
973 	.release	= nilfs_dev_attr_release,
974 };
975 
976 int nilfs_sysfs_create_device_group(struct super_block *sb)
977 {
978 	struct the_nilfs *nilfs = sb->s_fs_info;
979 	size_t devgrp_size = sizeof(struct nilfs_sysfs_dev_subgroups);
980 	int err;
981 
982 	nilfs->ns_dev_subgroups = kzalloc(devgrp_size, GFP_KERNEL);
983 	if (unlikely(!nilfs->ns_dev_subgroups)) {
984 		err = -ENOMEM;
985 		nilfs_err(sb, "unable to allocate memory for device group");
986 		goto failed_create_device_group;
987 	}
988 
989 	nilfs->ns_dev_kobj.kset = nilfs_kset;
990 	init_completion(&nilfs->ns_dev_kobj_unregister);
991 	err = kobject_init_and_add(&nilfs->ns_dev_kobj, &nilfs_dev_ktype, NULL,
992 				    "%s", sb->s_id);
993 	if (err)
994 		goto cleanup_dev_kobject;
995 
996 	err = nilfs_sysfs_create_mounted_snapshots_group(nilfs);
997 	if (err)
998 		goto cleanup_dev_kobject;
999 
1000 	err = nilfs_sysfs_create_checkpoints_group(nilfs);
1001 	if (err)
1002 		goto delete_mounted_snapshots_group;
1003 
1004 	err = nilfs_sysfs_create_segments_group(nilfs);
1005 	if (err)
1006 		goto delete_checkpoints_group;
1007 
1008 	err = nilfs_sysfs_create_superblock_group(nilfs);
1009 	if (err)
1010 		goto delete_segments_group;
1011 
1012 	err = nilfs_sysfs_create_segctor_group(nilfs);
1013 	if (err)
1014 		goto delete_superblock_group;
1015 
1016 	return 0;
1017 
1018 delete_superblock_group:
1019 	nilfs_sysfs_delete_superblock_group(nilfs);
1020 
1021 delete_segments_group:
1022 	nilfs_sysfs_delete_segments_group(nilfs);
1023 
1024 delete_checkpoints_group:
1025 	nilfs_sysfs_delete_checkpoints_group(nilfs);
1026 
1027 delete_mounted_snapshots_group:
1028 	nilfs_sysfs_delete_mounted_snapshots_group(nilfs);
1029 
1030 cleanup_dev_kobject:
1031 	kobject_put(&nilfs->ns_dev_kobj);
1032 	kfree(nilfs->ns_dev_subgroups);
1033 
1034 failed_create_device_group:
1035 	return err;
1036 }
1037 
1038 void nilfs_sysfs_delete_device_group(struct the_nilfs *nilfs)
1039 {
1040 	nilfs_sysfs_delete_mounted_snapshots_group(nilfs);
1041 	nilfs_sysfs_delete_checkpoints_group(nilfs);
1042 	nilfs_sysfs_delete_segments_group(nilfs);
1043 	nilfs_sysfs_delete_superblock_group(nilfs);
1044 	nilfs_sysfs_delete_segctor_group(nilfs);
1045 	kobject_del(&nilfs->ns_dev_kobj);
1046 	kobject_put(&nilfs->ns_dev_kobj);
1047 	kfree(nilfs->ns_dev_subgroups);
1048 }
1049 
1050 /************************************************************************
1051  *                        NILFS feature attrs                           *
1052  ************************************************************************/
1053 
1054 static ssize_t nilfs_feature_revision_show(struct kobject *kobj,
1055 					    struct attribute *attr, char *buf)
1056 {
1057 	return sysfs_emit(buf, "%d.%d\n",
1058 			NILFS_CURRENT_REV, NILFS_MINOR_REV);
1059 }
1060 
1061 static const char features_readme_str[] =
1062 	"The features group contains attributes that describe NILFS file\n"
1063 	"system driver features.\n\n"
1064 	"(1) revision\n\tshow current revision of NILFS file system driver.\n";
1065 
1066 static ssize_t nilfs_feature_README_show(struct kobject *kobj,
1067 					 struct attribute *attr,
1068 					 char *buf)
1069 {
1070 	return sysfs_emit(buf, features_readme_str);
1071 }
1072 
1073 NILFS_FEATURE_RO_ATTR(revision);
1074 NILFS_FEATURE_RO_ATTR(README);
1075 
1076 static struct attribute *nilfs_feature_attrs[] = {
1077 	NILFS_FEATURE_ATTR_LIST(revision),
1078 	NILFS_FEATURE_ATTR_LIST(README),
1079 	NULL,
1080 };
1081 
1082 static const struct attribute_group nilfs_feature_attr_group = {
1083 	.name = "features",
1084 	.attrs = nilfs_feature_attrs,
1085 };
1086 
1087 int __init nilfs_sysfs_init(void)
1088 {
1089 	int err;
1090 
1091 	nilfs_kset = kset_create_and_add(NILFS_ROOT_GROUP_NAME, NULL, fs_kobj);
1092 	if (!nilfs_kset) {
1093 		err = -ENOMEM;
1094 		nilfs_err(NULL, "unable to create sysfs entry: err=%d", err);
1095 		goto failed_sysfs_init;
1096 	}
1097 
1098 	err = sysfs_create_group(&nilfs_kset->kobj, &nilfs_feature_attr_group);
1099 	if (unlikely(err)) {
1100 		nilfs_err(NULL, "unable to create feature group: err=%d", err);
1101 		goto cleanup_sysfs_init;
1102 	}
1103 
1104 	return 0;
1105 
1106 cleanup_sysfs_init:
1107 	kset_unregister(nilfs_kset);
1108 
1109 failed_sysfs_init:
1110 	return err;
1111 }
1112 
1113 void nilfs_sysfs_exit(void)
1114 {
1115 	sysfs_remove_group(&nilfs_kset->kobj, &nilfs_feature_attr_group);
1116 	kset_unregister(nilfs_kset);
1117 }
1118