xref: /openbmc/linux/fs/nilfs2/sysfs.c (revision 6cd70754)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * sysfs.c - 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_SHOW_TIME(time_t_val, buf) ({ \
23 		struct tm res; \
24 		int count = 0; \
25 		time64_to_tm(time_t_val, 0, &res); \
26 		res.tm_year += 1900; \
27 		res.tm_mon += 1; \
28 		count = scnprintf(buf, PAGE_SIZE, \
29 				    "%ld-%.2d-%.2d %.2d:%.2d:%.2d\n", \
30 				    res.tm_year, res.tm_mon, res.tm_mday, \
31 				    res.tm_hour, res.tm_min, res.tm_sec);\
32 		count; \
33 })
34 
35 #define NILFS_DEV_INT_GROUP_OPS(name, parent_name) \
36 static ssize_t nilfs_##name##_attr_show(struct kobject *kobj, \
37 					struct attribute *attr, char *buf) \
38 { \
39 	struct the_nilfs *nilfs = container_of(kobj->parent, \
40 						struct the_nilfs, \
41 						ns_##parent_name##_kobj); \
42 	struct nilfs_##name##_attr *a = container_of(attr, \
43 						struct nilfs_##name##_attr, \
44 						attr); \
45 	return a->show ? a->show(a, nilfs, buf) : 0; \
46 } \
47 static ssize_t nilfs_##name##_attr_store(struct kobject *kobj, \
48 					 struct attribute *attr, \
49 					 const char *buf, size_t len) \
50 { \
51 	struct the_nilfs *nilfs = container_of(kobj->parent, \
52 						struct the_nilfs, \
53 						ns_##parent_name##_kobj); \
54 	struct nilfs_##name##_attr *a = container_of(attr, \
55 						struct nilfs_##name##_attr, \
56 						attr); \
57 	return a->store ? a->store(a, nilfs, buf, len) : 0; \
58 } \
59 static const struct sysfs_ops nilfs_##name##_attr_ops = { \
60 	.show	= nilfs_##name##_attr_show, \
61 	.store	= nilfs_##name##_attr_store, \
62 }
63 
64 #define NILFS_DEV_INT_GROUP_TYPE(name, parent_name) \
65 static void nilfs_##name##_attr_release(struct kobject *kobj) \
66 { \
67 	struct nilfs_sysfs_##parent_name##_subgroups *subgroups; \
68 	struct the_nilfs *nilfs = container_of(kobj->parent, \
69 						struct the_nilfs, \
70 						ns_##parent_name##_kobj); \
71 	subgroups = nilfs->ns_##parent_name##_subgroups; \
72 	complete(&subgroups->sg_##name##_kobj_unregister); \
73 } \
74 static struct kobj_type nilfs_##name##_ktype = { \
75 	.default_attrs	= nilfs_##name##_attrs, \
76 	.sysfs_ops	= &nilfs_##name##_attr_ops, \
77 	.release	= nilfs_##name##_attr_release, \
78 }
79 
80 #define NILFS_DEV_INT_GROUP_FNS(name, parent_name) \
81 static int nilfs_sysfs_create_##name##_group(struct the_nilfs *nilfs) \
82 { \
83 	struct kobject *parent; \
84 	struct kobject *kobj; \
85 	struct completion *kobj_unregister; \
86 	struct nilfs_sysfs_##parent_name##_subgroups *subgroups; \
87 	int err; \
88 	subgroups = nilfs->ns_##parent_name##_subgroups; \
89 	kobj = &subgroups->sg_##name##_kobj; \
90 	kobj_unregister = &subgroups->sg_##name##_kobj_unregister; \
91 	parent = &nilfs->ns_##parent_name##_kobj; \
92 	kobj->kset = nilfs_kset; \
93 	init_completion(kobj_unregister); \
94 	err = kobject_init_and_add(kobj, &nilfs_##name##_ktype, parent, \
95 				    #name); \
96 	if (err) \
97 		return err; \
98 	return 0; \
99 } \
100 static void nilfs_sysfs_delete_##name##_group(struct the_nilfs *nilfs) \
101 { \
102 	kobject_del(&nilfs->ns_##parent_name##_subgroups->sg_##name##_kobj); \
103 }
104 
105 /************************************************************************
106  *                        NILFS snapshot attrs                          *
107  ************************************************************************/
108 
109 static ssize_t
110 nilfs_snapshot_inodes_count_show(struct nilfs_snapshot_attr *attr,
111 				 struct nilfs_root *root, char *buf)
112 {
113 	return snprintf(buf, PAGE_SIZE, "%llu\n",
114 			(unsigned long long)atomic64_read(&root->inodes_count));
115 }
116 
117 static ssize_t
118 nilfs_snapshot_blocks_count_show(struct nilfs_snapshot_attr *attr,
119 				 struct nilfs_root *root, char *buf)
120 {
121 	return snprintf(buf, PAGE_SIZE, "%llu\n",
122 			(unsigned long long)atomic64_read(&root->blocks_count));
123 }
124 
125 static const char snapshot_readme_str[] =
126 	"The group contains details about mounted snapshot.\n\n"
127 	"(1) inodes_count\n\tshow number of inodes for snapshot.\n\n"
128 	"(2) blocks_count\n\tshow number of blocks for snapshot.\n\n";
129 
130 static ssize_t
131 nilfs_snapshot_README_show(struct nilfs_snapshot_attr *attr,
132 			    struct nilfs_root *root, char *buf)
133 {
134 	return snprintf(buf, PAGE_SIZE, snapshot_readme_str);
135 }
136 
137 NILFS_SNAPSHOT_RO_ATTR(inodes_count);
138 NILFS_SNAPSHOT_RO_ATTR(blocks_count);
139 NILFS_SNAPSHOT_RO_ATTR(README);
140 
141 static struct attribute *nilfs_snapshot_attrs[] = {
142 	NILFS_SNAPSHOT_ATTR_LIST(inodes_count),
143 	NILFS_SNAPSHOT_ATTR_LIST(blocks_count),
144 	NILFS_SNAPSHOT_ATTR_LIST(README),
145 	NULL,
146 };
147 
148 static ssize_t nilfs_snapshot_attr_show(struct kobject *kobj,
149 					struct attribute *attr, char *buf)
150 {
151 	struct nilfs_root *root =
152 			container_of(kobj, struct nilfs_root, snapshot_kobj);
153 	struct nilfs_snapshot_attr *a =
154 			container_of(attr, struct nilfs_snapshot_attr, attr);
155 
156 	return a->show ? a->show(a, root, buf) : 0;
157 }
158 
159 static ssize_t nilfs_snapshot_attr_store(struct kobject *kobj,
160 					 struct attribute *attr,
161 					 const char *buf, size_t len)
162 {
163 	struct nilfs_root *root =
164 			container_of(kobj, struct nilfs_root, snapshot_kobj);
165 	struct nilfs_snapshot_attr *a =
166 			container_of(attr, struct nilfs_snapshot_attr, attr);
167 
168 	return a->store ? a->store(a, root, buf, len) : 0;
169 }
170 
171 static void nilfs_snapshot_attr_release(struct kobject *kobj)
172 {
173 	struct nilfs_root *root = container_of(kobj, struct nilfs_root,
174 						snapshot_kobj);
175 	complete(&root->snapshot_kobj_unregister);
176 }
177 
178 static const struct sysfs_ops nilfs_snapshot_attr_ops = {
179 	.show	= nilfs_snapshot_attr_show,
180 	.store	= nilfs_snapshot_attr_store,
181 };
182 
183 static struct kobj_type nilfs_snapshot_ktype = {
184 	.default_attrs	= nilfs_snapshot_attrs,
185 	.sysfs_ops	= &nilfs_snapshot_attr_ops,
186 	.release	= nilfs_snapshot_attr_release,
187 };
188 
189 int nilfs_sysfs_create_snapshot_group(struct nilfs_root *root)
190 {
191 	struct the_nilfs *nilfs;
192 	struct kobject *parent;
193 	int err;
194 
195 	nilfs = root->nilfs;
196 	parent = &nilfs->ns_dev_subgroups->sg_mounted_snapshots_kobj;
197 	root->snapshot_kobj.kset = nilfs_kset;
198 	init_completion(&root->snapshot_kobj_unregister);
199 
200 	if (root->cno == NILFS_CPTREE_CURRENT_CNO) {
201 		err = kobject_init_and_add(&root->snapshot_kobj,
202 					    &nilfs_snapshot_ktype,
203 					    &nilfs->ns_dev_kobj,
204 					    "current_checkpoint");
205 	} else {
206 		err = kobject_init_and_add(&root->snapshot_kobj,
207 					    &nilfs_snapshot_ktype,
208 					    parent,
209 					    "%llu", root->cno);
210 	}
211 
212 	if (err)
213 		return err;
214 
215 	return 0;
216 }
217 
218 void nilfs_sysfs_delete_snapshot_group(struct nilfs_root *root)
219 {
220 	kobject_del(&root->snapshot_kobj);
221 }
222 
223 /************************************************************************
224  *                    NILFS mounted snapshots attrs                     *
225  ************************************************************************/
226 
227 static const char mounted_snapshots_readme_str[] =
228 	"The mounted_snapshots group contains group for\n"
229 	"every mounted snapshot.\n";
230 
231 static ssize_t
232 nilfs_mounted_snapshots_README_show(struct nilfs_mounted_snapshots_attr *attr,
233 				    struct the_nilfs *nilfs, char *buf)
234 {
235 	return snprintf(buf, PAGE_SIZE, mounted_snapshots_readme_str);
236 }
237 
238 NILFS_MOUNTED_SNAPSHOTS_RO_ATTR(README);
239 
240 static struct attribute *nilfs_mounted_snapshots_attrs[] = {
241 	NILFS_MOUNTED_SNAPSHOTS_ATTR_LIST(README),
242 	NULL,
243 };
244 
245 NILFS_DEV_INT_GROUP_OPS(mounted_snapshots, dev);
246 NILFS_DEV_INT_GROUP_TYPE(mounted_snapshots, dev);
247 NILFS_DEV_INT_GROUP_FNS(mounted_snapshots, dev);
248 
249 /************************************************************************
250  *                      NILFS checkpoints attrs                         *
251  ************************************************************************/
252 
253 static ssize_t
254 nilfs_checkpoints_checkpoints_number_show(struct nilfs_checkpoints_attr *attr,
255 					    struct the_nilfs *nilfs,
256 					    char *buf)
257 {
258 	__u64 ncheckpoints;
259 	struct nilfs_cpstat cpstat;
260 	int err;
261 
262 	down_read(&nilfs->ns_segctor_sem);
263 	err = nilfs_cpfile_get_stat(nilfs->ns_cpfile, &cpstat);
264 	up_read(&nilfs->ns_segctor_sem);
265 	if (err < 0) {
266 		nilfs_err(nilfs->ns_sb, "unable to get checkpoint stat: err=%d",
267 			  err);
268 		return err;
269 	}
270 
271 	ncheckpoints = cpstat.cs_ncps;
272 
273 	return snprintf(buf, PAGE_SIZE, "%llu\n", ncheckpoints);
274 }
275 
276 static ssize_t
277 nilfs_checkpoints_snapshots_number_show(struct nilfs_checkpoints_attr *attr,
278 					struct the_nilfs *nilfs,
279 					char *buf)
280 {
281 	__u64 nsnapshots;
282 	struct nilfs_cpstat cpstat;
283 	int err;
284 
285 	down_read(&nilfs->ns_segctor_sem);
286 	err = nilfs_cpfile_get_stat(nilfs->ns_cpfile, &cpstat);
287 	up_read(&nilfs->ns_segctor_sem);
288 	if (err < 0) {
289 		nilfs_err(nilfs->ns_sb, "unable to get checkpoint stat: err=%d",
290 			  err);
291 		return err;
292 	}
293 
294 	nsnapshots = cpstat.cs_nsss;
295 
296 	return snprintf(buf, PAGE_SIZE, "%llu\n", nsnapshots);
297 }
298 
299 static ssize_t
300 nilfs_checkpoints_last_seg_checkpoint_show(struct nilfs_checkpoints_attr *attr,
301 					    struct the_nilfs *nilfs,
302 					    char *buf)
303 {
304 	__u64 last_cno;
305 
306 	spin_lock(&nilfs->ns_last_segment_lock);
307 	last_cno = nilfs->ns_last_cno;
308 	spin_unlock(&nilfs->ns_last_segment_lock);
309 
310 	return snprintf(buf, PAGE_SIZE, "%llu\n", last_cno);
311 }
312 
313 static ssize_t
314 nilfs_checkpoints_next_checkpoint_show(struct nilfs_checkpoints_attr *attr,
315 					struct the_nilfs *nilfs,
316 					char *buf)
317 {
318 	__u64 cno;
319 
320 	down_read(&nilfs->ns_segctor_sem);
321 	cno = nilfs->ns_cno;
322 	up_read(&nilfs->ns_segctor_sem);
323 
324 	return snprintf(buf, PAGE_SIZE, "%llu\n", cno);
325 }
326 
327 static const char checkpoints_readme_str[] =
328 	"The checkpoints group contains attributes that describe\n"
329 	"details about volume's checkpoints.\n\n"
330 	"(1) checkpoints_number\n\tshow number of checkpoints on volume.\n\n"
331 	"(2) snapshots_number\n\tshow number of snapshots on volume.\n\n"
332 	"(3) last_seg_checkpoint\n"
333 	"\tshow checkpoint number of the latest segment.\n\n"
334 	"(4) next_checkpoint\n\tshow next checkpoint number.\n\n";
335 
336 static ssize_t
337 nilfs_checkpoints_README_show(struct nilfs_checkpoints_attr *attr,
338 				struct the_nilfs *nilfs, char *buf)
339 {
340 	return snprintf(buf, PAGE_SIZE, checkpoints_readme_str);
341 }
342 
343 NILFS_CHECKPOINTS_RO_ATTR(checkpoints_number);
344 NILFS_CHECKPOINTS_RO_ATTR(snapshots_number);
345 NILFS_CHECKPOINTS_RO_ATTR(last_seg_checkpoint);
346 NILFS_CHECKPOINTS_RO_ATTR(next_checkpoint);
347 NILFS_CHECKPOINTS_RO_ATTR(README);
348 
349 static struct attribute *nilfs_checkpoints_attrs[] = {
350 	NILFS_CHECKPOINTS_ATTR_LIST(checkpoints_number),
351 	NILFS_CHECKPOINTS_ATTR_LIST(snapshots_number),
352 	NILFS_CHECKPOINTS_ATTR_LIST(last_seg_checkpoint),
353 	NILFS_CHECKPOINTS_ATTR_LIST(next_checkpoint),
354 	NILFS_CHECKPOINTS_ATTR_LIST(README),
355 	NULL,
356 };
357 
358 NILFS_DEV_INT_GROUP_OPS(checkpoints, dev);
359 NILFS_DEV_INT_GROUP_TYPE(checkpoints, dev);
360 NILFS_DEV_INT_GROUP_FNS(checkpoints, dev);
361 
362 /************************************************************************
363  *                        NILFS segments attrs                          *
364  ************************************************************************/
365 
366 static ssize_t
367 nilfs_segments_segments_number_show(struct nilfs_segments_attr *attr,
368 				     struct the_nilfs *nilfs,
369 				     char *buf)
370 {
371 	return snprintf(buf, PAGE_SIZE, "%lu\n", nilfs->ns_nsegments);
372 }
373 
374 static ssize_t
375 nilfs_segments_blocks_per_segment_show(struct nilfs_segments_attr *attr,
376 					struct the_nilfs *nilfs,
377 					char *buf)
378 {
379 	return snprintf(buf, PAGE_SIZE, "%lu\n", nilfs->ns_blocks_per_segment);
380 }
381 
382 static ssize_t
383 nilfs_segments_clean_segments_show(struct nilfs_segments_attr *attr,
384 				    struct the_nilfs *nilfs,
385 				    char *buf)
386 {
387 	unsigned long ncleansegs;
388 
389 	down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
390 	ncleansegs = nilfs_sufile_get_ncleansegs(nilfs->ns_sufile);
391 	up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
392 
393 	return snprintf(buf, PAGE_SIZE, "%lu\n", ncleansegs);
394 }
395 
396 static ssize_t
397 nilfs_segments_dirty_segments_show(struct nilfs_segments_attr *attr,
398 				    struct the_nilfs *nilfs,
399 				    char *buf)
400 {
401 	struct nilfs_sustat sustat;
402 	int err;
403 
404 	down_read(&nilfs->ns_segctor_sem);
405 	err = nilfs_sufile_get_stat(nilfs->ns_sufile, &sustat);
406 	up_read(&nilfs->ns_segctor_sem);
407 	if (err < 0) {
408 		nilfs_err(nilfs->ns_sb, "unable to get segment stat: err=%d",
409 			  err);
410 		return err;
411 	}
412 
413 	return snprintf(buf, PAGE_SIZE, "%llu\n", sustat.ss_ndirtysegs);
414 }
415 
416 static const char segments_readme_str[] =
417 	"The segments group contains attributes that describe\n"
418 	"details about volume's segments.\n\n"
419 	"(1) segments_number\n\tshow number of segments on volume.\n\n"
420 	"(2) blocks_per_segment\n\tshow number of blocks in segment.\n\n"
421 	"(3) clean_segments\n\tshow count of clean segments.\n\n"
422 	"(4) dirty_segments\n\tshow count of dirty segments.\n\n";
423 
424 static ssize_t
425 nilfs_segments_README_show(struct nilfs_segments_attr *attr,
426 			    struct the_nilfs *nilfs,
427 			    char *buf)
428 {
429 	return snprintf(buf, PAGE_SIZE, segments_readme_str);
430 }
431 
432 NILFS_SEGMENTS_RO_ATTR(segments_number);
433 NILFS_SEGMENTS_RO_ATTR(blocks_per_segment);
434 NILFS_SEGMENTS_RO_ATTR(clean_segments);
435 NILFS_SEGMENTS_RO_ATTR(dirty_segments);
436 NILFS_SEGMENTS_RO_ATTR(README);
437 
438 static struct attribute *nilfs_segments_attrs[] = {
439 	NILFS_SEGMENTS_ATTR_LIST(segments_number),
440 	NILFS_SEGMENTS_ATTR_LIST(blocks_per_segment),
441 	NILFS_SEGMENTS_ATTR_LIST(clean_segments),
442 	NILFS_SEGMENTS_ATTR_LIST(dirty_segments),
443 	NILFS_SEGMENTS_ATTR_LIST(README),
444 	NULL,
445 };
446 
447 NILFS_DEV_INT_GROUP_OPS(segments, dev);
448 NILFS_DEV_INT_GROUP_TYPE(segments, dev);
449 NILFS_DEV_INT_GROUP_FNS(segments, dev);
450 
451 /************************************************************************
452  *                        NILFS segctor attrs                           *
453  ************************************************************************/
454 
455 static ssize_t
456 nilfs_segctor_last_pseg_block_show(struct nilfs_segctor_attr *attr,
457 				    struct the_nilfs *nilfs,
458 				    char *buf)
459 {
460 	sector_t last_pseg;
461 
462 	spin_lock(&nilfs->ns_last_segment_lock);
463 	last_pseg = nilfs->ns_last_pseg;
464 	spin_unlock(&nilfs->ns_last_segment_lock);
465 
466 	return snprintf(buf, PAGE_SIZE, "%llu\n",
467 			(unsigned long long)last_pseg);
468 }
469 
470 static ssize_t
471 nilfs_segctor_last_seg_sequence_show(struct nilfs_segctor_attr *attr,
472 					struct the_nilfs *nilfs,
473 					char *buf)
474 {
475 	u64 last_seq;
476 
477 	spin_lock(&nilfs->ns_last_segment_lock);
478 	last_seq = nilfs->ns_last_seq;
479 	spin_unlock(&nilfs->ns_last_segment_lock);
480 
481 	return snprintf(buf, PAGE_SIZE, "%llu\n", last_seq);
482 }
483 
484 static ssize_t
485 nilfs_segctor_last_seg_checkpoint_show(struct nilfs_segctor_attr *attr,
486 					struct the_nilfs *nilfs,
487 					char *buf)
488 {
489 	__u64 last_cno;
490 
491 	spin_lock(&nilfs->ns_last_segment_lock);
492 	last_cno = nilfs->ns_last_cno;
493 	spin_unlock(&nilfs->ns_last_segment_lock);
494 
495 	return snprintf(buf, PAGE_SIZE, "%llu\n", last_cno);
496 }
497 
498 static ssize_t
499 nilfs_segctor_current_seg_sequence_show(struct nilfs_segctor_attr *attr,
500 					struct the_nilfs *nilfs,
501 					char *buf)
502 {
503 	u64 seg_seq;
504 
505 	down_read(&nilfs->ns_segctor_sem);
506 	seg_seq = nilfs->ns_seg_seq;
507 	up_read(&nilfs->ns_segctor_sem);
508 
509 	return snprintf(buf, PAGE_SIZE, "%llu\n", seg_seq);
510 }
511 
512 static ssize_t
513 nilfs_segctor_current_last_full_seg_show(struct nilfs_segctor_attr *attr,
514 					 struct the_nilfs *nilfs,
515 					 char *buf)
516 {
517 	__u64 segnum;
518 
519 	down_read(&nilfs->ns_segctor_sem);
520 	segnum = nilfs->ns_segnum;
521 	up_read(&nilfs->ns_segctor_sem);
522 
523 	return snprintf(buf, PAGE_SIZE, "%llu\n", segnum);
524 }
525 
526 static ssize_t
527 nilfs_segctor_next_full_seg_show(struct nilfs_segctor_attr *attr,
528 				 struct the_nilfs *nilfs,
529 				 char *buf)
530 {
531 	__u64 nextnum;
532 
533 	down_read(&nilfs->ns_segctor_sem);
534 	nextnum = nilfs->ns_nextnum;
535 	up_read(&nilfs->ns_segctor_sem);
536 
537 	return snprintf(buf, PAGE_SIZE, "%llu\n", nextnum);
538 }
539 
540 static ssize_t
541 nilfs_segctor_next_pseg_offset_show(struct nilfs_segctor_attr *attr,
542 					struct the_nilfs *nilfs,
543 					char *buf)
544 {
545 	unsigned long pseg_offset;
546 
547 	down_read(&nilfs->ns_segctor_sem);
548 	pseg_offset = nilfs->ns_pseg_offset;
549 	up_read(&nilfs->ns_segctor_sem);
550 
551 	return snprintf(buf, PAGE_SIZE, "%lu\n", pseg_offset);
552 }
553 
554 static ssize_t
555 nilfs_segctor_next_checkpoint_show(struct nilfs_segctor_attr *attr,
556 					struct the_nilfs *nilfs,
557 					char *buf)
558 {
559 	__u64 cno;
560 
561 	down_read(&nilfs->ns_segctor_sem);
562 	cno = nilfs->ns_cno;
563 	up_read(&nilfs->ns_segctor_sem);
564 
565 	return snprintf(buf, PAGE_SIZE, "%llu\n", cno);
566 }
567 
568 static ssize_t
569 nilfs_segctor_last_seg_write_time_show(struct nilfs_segctor_attr *attr,
570 					struct the_nilfs *nilfs,
571 					char *buf)
572 {
573 	time64_t ctime;
574 
575 	down_read(&nilfs->ns_segctor_sem);
576 	ctime = nilfs->ns_ctime;
577 	up_read(&nilfs->ns_segctor_sem);
578 
579 	return NILFS_SHOW_TIME(ctime, buf);
580 }
581 
582 static ssize_t
583 nilfs_segctor_last_seg_write_time_secs_show(struct nilfs_segctor_attr *attr,
584 					    struct the_nilfs *nilfs,
585 					    char *buf)
586 {
587 	time64_t ctime;
588 
589 	down_read(&nilfs->ns_segctor_sem);
590 	ctime = nilfs->ns_ctime;
591 	up_read(&nilfs->ns_segctor_sem);
592 
593 	return snprintf(buf, PAGE_SIZE, "%llu\n", ctime);
594 }
595 
596 static ssize_t
597 nilfs_segctor_last_nongc_write_time_show(struct nilfs_segctor_attr *attr,
598 					 struct the_nilfs *nilfs,
599 					 char *buf)
600 {
601 	time64_t nongc_ctime;
602 
603 	down_read(&nilfs->ns_segctor_sem);
604 	nongc_ctime = nilfs->ns_nongc_ctime;
605 	up_read(&nilfs->ns_segctor_sem);
606 
607 	return NILFS_SHOW_TIME(nongc_ctime, buf);
608 }
609 
610 static ssize_t
611 nilfs_segctor_last_nongc_write_time_secs_show(struct nilfs_segctor_attr *attr,
612 						struct the_nilfs *nilfs,
613 						char *buf)
614 {
615 	time64_t nongc_ctime;
616 
617 	down_read(&nilfs->ns_segctor_sem);
618 	nongc_ctime = nilfs->ns_nongc_ctime;
619 	up_read(&nilfs->ns_segctor_sem);
620 
621 	return snprintf(buf, PAGE_SIZE, "%llu\n", nongc_ctime);
622 }
623 
624 static ssize_t
625 nilfs_segctor_dirty_data_blocks_count_show(struct nilfs_segctor_attr *attr,
626 					    struct the_nilfs *nilfs,
627 					    char *buf)
628 {
629 	u32 ndirtyblks;
630 
631 	down_read(&nilfs->ns_segctor_sem);
632 	ndirtyblks = atomic_read(&nilfs->ns_ndirtyblks);
633 	up_read(&nilfs->ns_segctor_sem);
634 
635 	return snprintf(buf, PAGE_SIZE, "%u\n", ndirtyblks);
636 }
637 
638 static const char segctor_readme_str[] =
639 	"The segctor group contains attributes that describe\n"
640 	"segctor thread activity details.\n\n"
641 	"(1) last_pseg_block\n"
642 	"\tshow start block number of the latest segment.\n\n"
643 	"(2) last_seg_sequence\n"
644 	"\tshow sequence value of the latest segment.\n\n"
645 	"(3) last_seg_checkpoint\n"
646 	"\tshow checkpoint number of the latest segment.\n\n"
647 	"(4) current_seg_sequence\n\tshow segment sequence counter.\n\n"
648 	"(5) current_last_full_seg\n"
649 	"\tshow index number of the latest full segment.\n\n"
650 	"(6) next_full_seg\n"
651 	"\tshow index number of the full segment index to be used next.\n\n"
652 	"(7) next_pseg_offset\n"
653 	"\tshow offset of next partial segment in the current full segment.\n\n"
654 	"(8) next_checkpoint\n\tshow next checkpoint number.\n\n"
655 	"(9) last_seg_write_time\n"
656 	"\tshow write time of the last segment in human-readable format.\n\n"
657 	"(10) last_seg_write_time_secs\n"
658 	"\tshow write time of the last segment in seconds.\n\n"
659 	"(11) last_nongc_write_time\n"
660 	"\tshow write time of the last segment not for cleaner operation "
661 	"in human-readable format.\n\n"
662 	"(12) last_nongc_write_time_secs\n"
663 	"\tshow write time of the last segment not for cleaner operation "
664 	"in seconds.\n\n"
665 	"(13) dirty_data_blocks_count\n"
666 	"\tshow number of dirty data blocks.\n\n";
667 
668 static ssize_t
669 nilfs_segctor_README_show(struct nilfs_segctor_attr *attr,
670 			  struct the_nilfs *nilfs, char *buf)
671 {
672 	return snprintf(buf, PAGE_SIZE, segctor_readme_str);
673 }
674 
675 NILFS_SEGCTOR_RO_ATTR(last_pseg_block);
676 NILFS_SEGCTOR_RO_ATTR(last_seg_sequence);
677 NILFS_SEGCTOR_RO_ATTR(last_seg_checkpoint);
678 NILFS_SEGCTOR_RO_ATTR(current_seg_sequence);
679 NILFS_SEGCTOR_RO_ATTR(current_last_full_seg);
680 NILFS_SEGCTOR_RO_ATTR(next_full_seg);
681 NILFS_SEGCTOR_RO_ATTR(next_pseg_offset);
682 NILFS_SEGCTOR_RO_ATTR(next_checkpoint);
683 NILFS_SEGCTOR_RO_ATTR(last_seg_write_time);
684 NILFS_SEGCTOR_RO_ATTR(last_seg_write_time_secs);
685 NILFS_SEGCTOR_RO_ATTR(last_nongc_write_time);
686 NILFS_SEGCTOR_RO_ATTR(last_nongc_write_time_secs);
687 NILFS_SEGCTOR_RO_ATTR(dirty_data_blocks_count);
688 NILFS_SEGCTOR_RO_ATTR(README);
689 
690 static struct attribute *nilfs_segctor_attrs[] = {
691 	NILFS_SEGCTOR_ATTR_LIST(last_pseg_block),
692 	NILFS_SEGCTOR_ATTR_LIST(last_seg_sequence),
693 	NILFS_SEGCTOR_ATTR_LIST(last_seg_checkpoint),
694 	NILFS_SEGCTOR_ATTR_LIST(current_seg_sequence),
695 	NILFS_SEGCTOR_ATTR_LIST(current_last_full_seg),
696 	NILFS_SEGCTOR_ATTR_LIST(next_full_seg),
697 	NILFS_SEGCTOR_ATTR_LIST(next_pseg_offset),
698 	NILFS_SEGCTOR_ATTR_LIST(next_checkpoint),
699 	NILFS_SEGCTOR_ATTR_LIST(last_seg_write_time),
700 	NILFS_SEGCTOR_ATTR_LIST(last_seg_write_time_secs),
701 	NILFS_SEGCTOR_ATTR_LIST(last_nongc_write_time),
702 	NILFS_SEGCTOR_ATTR_LIST(last_nongc_write_time_secs),
703 	NILFS_SEGCTOR_ATTR_LIST(dirty_data_blocks_count),
704 	NILFS_SEGCTOR_ATTR_LIST(README),
705 	NULL,
706 };
707 
708 NILFS_DEV_INT_GROUP_OPS(segctor, dev);
709 NILFS_DEV_INT_GROUP_TYPE(segctor, dev);
710 NILFS_DEV_INT_GROUP_FNS(segctor, dev);
711 
712 /************************************************************************
713  *                        NILFS superblock attrs                        *
714  ************************************************************************/
715 
716 static ssize_t
717 nilfs_superblock_sb_write_time_show(struct nilfs_superblock_attr *attr,
718 				     struct the_nilfs *nilfs,
719 				     char *buf)
720 {
721 	time64_t sbwtime;
722 
723 	down_read(&nilfs->ns_sem);
724 	sbwtime = nilfs->ns_sbwtime;
725 	up_read(&nilfs->ns_sem);
726 
727 	return NILFS_SHOW_TIME(sbwtime, buf);
728 }
729 
730 static ssize_t
731 nilfs_superblock_sb_write_time_secs_show(struct nilfs_superblock_attr *attr,
732 					 struct the_nilfs *nilfs,
733 					 char *buf)
734 {
735 	time64_t sbwtime;
736 
737 	down_read(&nilfs->ns_sem);
738 	sbwtime = nilfs->ns_sbwtime;
739 	up_read(&nilfs->ns_sem);
740 
741 	return snprintf(buf, PAGE_SIZE, "%llu\n", sbwtime);
742 }
743 
744 static ssize_t
745 nilfs_superblock_sb_write_count_show(struct nilfs_superblock_attr *attr,
746 				      struct the_nilfs *nilfs,
747 				      char *buf)
748 {
749 	unsigned int sbwcount;
750 
751 	down_read(&nilfs->ns_sem);
752 	sbwcount = nilfs->ns_sbwcount;
753 	up_read(&nilfs->ns_sem);
754 
755 	return snprintf(buf, PAGE_SIZE, "%u\n", sbwcount);
756 }
757 
758 static ssize_t
759 nilfs_superblock_sb_update_frequency_show(struct nilfs_superblock_attr *attr,
760 					    struct the_nilfs *nilfs,
761 					    char *buf)
762 {
763 	unsigned int sb_update_freq;
764 
765 	down_read(&nilfs->ns_sem);
766 	sb_update_freq = nilfs->ns_sb_update_freq;
767 	up_read(&nilfs->ns_sem);
768 
769 	return snprintf(buf, PAGE_SIZE, "%u\n", sb_update_freq);
770 }
771 
772 static ssize_t
773 nilfs_superblock_sb_update_frequency_store(struct nilfs_superblock_attr *attr,
774 					    struct the_nilfs *nilfs,
775 					    const char *buf, size_t count)
776 {
777 	unsigned int val;
778 	int err;
779 
780 	err = kstrtouint(skip_spaces(buf), 0, &val);
781 	if (err) {
782 		nilfs_err(nilfs->ns_sb, "unable to convert string: err=%d",
783 			  err);
784 		return err;
785 	}
786 
787 	if (val < NILFS_SB_FREQ) {
788 		val = NILFS_SB_FREQ;
789 		nilfs_warn(nilfs->ns_sb,
790 			   "superblock update frequency cannot be lesser than 10 seconds");
791 	}
792 
793 	down_write(&nilfs->ns_sem);
794 	nilfs->ns_sb_update_freq = val;
795 	up_write(&nilfs->ns_sem);
796 
797 	return count;
798 }
799 
800 static const char sb_readme_str[] =
801 	"The superblock group contains attributes that describe\n"
802 	"superblock's details.\n\n"
803 	"(1) sb_write_time\n\tshow previous write time of super block "
804 	"in human-readable format.\n\n"
805 	"(2) sb_write_time_secs\n\tshow previous write time of super block "
806 	"in seconds.\n\n"
807 	"(3) sb_write_count\n\tshow write count of super block.\n\n"
808 	"(4) sb_update_frequency\n"
809 	"\tshow/set interval of periodical update of superblock (in seconds).\n\n"
810 	"\tYou can set preferable frequency of superblock update by command:\n\n"
811 	"\t'echo <val> > /sys/fs/<nilfs>/<dev>/superblock/sb_update_frequency'\n";
812 
813 static ssize_t
814 nilfs_superblock_README_show(struct nilfs_superblock_attr *attr,
815 				struct the_nilfs *nilfs, char *buf)
816 {
817 	return snprintf(buf, PAGE_SIZE, sb_readme_str);
818 }
819 
820 NILFS_SUPERBLOCK_RO_ATTR(sb_write_time);
821 NILFS_SUPERBLOCK_RO_ATTR(sb_write_time_secs);
822 NILFS_SUPERBLOCK_RO_ATTR(sb_write_count);
823 NILFS_SUPERBLOCK_RW_ATTR(sb_update_frequency);
824 NILFS_SUPERBLOCK_RO_ATTR(README);
825 
826 static struct attribute *nilfs_superblock_attrs[] = {
827 	NILFS_SUPERBLOCK_ATTR_LIST(sb_write_time),
828 	NILFS_SUPERBLOCK_ATTR_LIST(sb_write_time_secs),
829 	NILFS_SUPERBLOCK_ATTR_LIST(sb_write_count),
830 	NILFS_SUPERBLOCK_ATTR_LIST(sb_update_frequency),
831 	NILFS_SUPERBLOCK_ATTR_LIST(README),
832 	NULL,
833 };
834 
835 NILFS_DEV_INT_GROUP_OPS(superblock, dev);
836 NILFS_DEV_INT_GROUP_TYPE(superblock, dev);
837 NILFS_DEV_INT_GROUP_FNS(superblock, dev);
838 
839 /************************************************************************
840  *                        NILFS device attrs                            *
841  ************************************************************************/
842 
843 static
844 ssize_t nilfs_dev_revision_show(struct nilfs_dev_attr *attr,
845 				struct the_nilfs *nilfs,
846 				char *buf)
847 {
848 	struct nilfs_super_block **sbp = nilfs->ns_sbp;
849 	u32 major = le32_to_cpu(sbp[0]->s_rev_level);
850 	u16 minor = le16_to_cpu(sbp[0]->s_minor_rev_level);
851 
852 	return snprintf(buf, PAGE_SIZE, "%d.%d\n", major, minor);
853 }
854 
855 static
856 ssize_t nilfs_dev_blocksize_show(struct nilfs_dev_attr *attr,
857 				 struct the_nilfs *nilfs,
858 				 char *buf)
859 {
860 	return snprintf(buf, PAGE_SIZE, "%u\n", nilfs->ns_blocksize);
861 }
862 
863 static
864 ssize_t nilfs_dev_device_size_show(struct nilfs_dev_attr *attr,
865 				    struct the_nilfs *nilfs,
866 				    char *buf)
867 {
868 	struct nilfs_super_block **sbp = nilfs->ns_sbp;
869 	u64 dev_size = le64_to_cpu(sbp[0]->s_dev_size);
870 
871 	return snprintf(buf, PAGE_SIZE, "%llu\n", dev_size);
872 }
873 
874 static
875 ssize_t nilfs_dev_free_blocks_show(struct nilfs_dev_attr *attr,
876 				   struct the_nilfs *nilfs,
877 				   char *buf)
878 {
879 	sector_t free_blocks = 0;
880 
881 	nilfs_count_free_blocks(nilfs, &free_blocks);
882 	return snprintf(buf, PAGE_SIZE, "%llu\n",
883 			(unsigned long long)free_blocks);
884 }
885 
886 static
887 ssize_t nilfs_dev_uuid_show(struct nilfs_dev_attr *attr,
888 			    struct the_nilfs *nilfs,
889 			    char *buf)
890 {
891 	struct nilfs_super_block **sbp = nilfs->ns_sbp;
892 
893 	return snprintf(buf, PAGE_SIZE, "%pUb\n", sbp[0]->s_uuid);
894 }
895 
896 static
897 ssize_t nilfs_dev_volume_name_show(struct nilfs_dev_attr *attr,
898 				    struct the_nilfs *nilfs,
899 				    char *buf)
900 {
901 	struct nilfs_super_block **sbp = nilfs->ns_sbp;
902 
903 	return scnprintf(buf, sizeof(sbp[0]->s_volume_name), "%s\n",
904 			 sbp[0]->s_volume_name);
905 }
906 
907 static const char dev_readme_str[] =
908 	"The <device> group contains attributes that describe file system\n"
909 	"partition's details.\n\n"
910 	"(1) revision\n\tshow NILFS file system revision.\n\n"
911 	"(2) blocksize\n\tshow volume block size in bytes.\n\n"
912 	"(3) device_size\n\tshow volume size in bytes.\n\n"
913 	"(4) free_blocks\n\tshow count of free blocks on volume.\n\n"
914 	"(5) uuid\n\tshow volume's UUID.\n\n"
915 	"(6) volume_name\n\tshow volume's name.\n\n";
916 
917 static ssize_t nilfs_dev_README_show(struct nilfs_dev_attr *attr,
918 				     struct the_nilfs *nilfs,
919 				     char *buf)
920 {
921 	return snprintf(buf, PAGE_SIZE, dev_readme_str);
922 }
923 
924 NILFS_DEV_RO_ATTR(revision);
925 NILFS_DEV_RO_ATTR(blocksize);
926 NILFS_DEV_RO_ATTR(device_size);
927 NILFS_DEV_RO_ATTR(free_blocks);
928 NILFS_DEV_RO_ATTR(uuid);
929 NILFS_DEV_RO_ATTR(volume_name);
930 NILFS_DEV_RO_ATTR(README);
931 
932 static struct attribute *nilfs_dev_attrs[] = {
933 	NILFS_DEV_ATTR_LIST(revision),
934 	NILFS_DEV_ATTR_LIST(blocksize),
935 	NILFS_DEV_ATTR_LIST(device_size),
936 	NILFS_DEV_ATTR_LIST(free_blocks),
937 	NILFS_DEV_ATTR_LIST(uuid),
938 	NILFS_DEV_ATTR_LIST(volume_name),
939 	NILFS_DEV_ATTR_LIST(README),
940 	NULL,
941 };
942 
943 static ssize_t nilfs_dev_attr_show(struct kobject *kobj,
944 				    struct attribute *attr, char *buf)
945 {
946 	struct the_nilfs *nilfs = container_of(kobj, struct the_nilfs,
947 						ns_dev_kobj);
948 	struct nilfs_dev_attr *a = container_of(attr, struct nilfs_dev_attr,
949 						attr);
950 
951 	return a->show ? a->show(a, nilfs, buf) : 0;
952 }
953 
954 static ssize_t nilfs_dev_attr_store(struct kobject *kobj,
955 				    struct attribute *attr,
956 				    const char *buf, size_t len)
957 {
958 	struct the_nilfs *nilfs = container_of(kobj, struct the_nilfs,
959 						ns_dev_kobj);
960 	struct nilfs_dev_attr *a = container_of(attr, struct nilfs_dev_attr,
961 						attr);
962 
963 	return a->store ? a->store(a, nilfs, buf, len) : 0;
964 }
965 
966 static void nilfs_dev_attr_release(struct kobject *kobj)
967 {
968 	struct the_nilfs *nilfs = container_of(kobj, struct the_nilfs,
969 						ns_dev_kobj);
970 	complete(&nilfs->ns_dev_kobj_unregister);
971 }
972 
973 static const struct sysfs_ops nilfs_dev_attr_ops = {
974 	.show	= nilfs_dev_attr_show,
975 	.store	= nilfs_dev_attr_store,
976 };
977 
978 static struct kobj_type nilfs_dev_ktype = {
979 	.default_attrs	= nilfs_dev_attrs,
980 	.sysfs_ops	= &nilfs_dev_attr_ops,
981 	.release	= nilfs_dev_attr_release,
982 };
983 
984 int nilfs_sysfs_create_device_group(struct super_block *sb)
985 {
986 	struct the_nilfs *nilfs = sb->s_fs_info;
987 	size_t devgrp_size = sizeof(struct nilfs_sysfs_dev_subgroups);
988 	int err;
989 
990 	nilfs->ns_dev_subgroups = kzalloc(devgrp_size, GFP_KERNEL);
991 	if (unlikely(!nilfs->ns_dev_subgroups)) {
992 		err = -ENOMEM;
993 		nilfs_err(sb, "unable to allocate memory for device group");
994 		goto failed_create_device_group;
995 	}
996 
997 	nilfs->ns_dev_kobj.kset = nilfs_kset;
998 	init_completion(&nilfs->ns_dev_kobj_unregister);
999 	err = kobject_init_and_add(&nilfs->ns_dev_kobj, &nilfs_dev_ktype, NULL,
1000 				    "%s", sb->s_id);
1001 	if (err)
1002 		goto free_dev_subgroups;
1003 
1004 	err = nilfs_sysfs_create_mounted_snapshots_group(nilfs);
1005 	if (err)
1006 		goto cleanup_dev_kobject;
1007 
1008 	err = nilfs_sysfs_create_checkpoints_group(nilfs);
1009 	if (err)
1010 		goto delete_mounted_snapshots_group;
1011 
1012 	err = nilfs_sysfs_create_segments_group(nilfs);
1013 	if (err)
1014 		goto delete_checkpoints_group;
1015 
1016 	err = nilfs_sysfs_create_superblock_group(nilfs);
1017 	if (err)
1018 		goto delete_segments_group;
1019 
1020 	err = nilfs_sysfs_create_segctor_group(nilfs);
1021 	if (err)
1022 		goto delete_superblock_group;
1023 
1024 	return 0;
1025 
1026 delete_superblock_group:
1027 	nilfs_sysfs_delete_superblock_group(nilfs);
1028 
1029 delete_segments_group:
1030 	nilfs_sysfs_delete_segments_group(nilfs);
1031 
1032 delete_checkpoints_group:
1033 	nilfs_sysfs_delete_checkpoints_group(nilfs);
1034 
1035 delete_mounted_snapshots_group:
1036 	nilfs_sysfs_delete_mounted_snapshots_group(nilfs);
1037 
1038 cleanup_dev_kobject:
1039 	kobject_del(&nilfs->ns_dev_kobj);
1040 
1041 free_dev_subgroups:
1042 	kfree(nilfs->ns_dev_subgroups);
1043 
1044 failed_create_device_group:
1045 	return err;
1046 }
1047 
1048 void nilfs_sysfs_delete_device_group(struct the_nilfs *nilfs)
1049 {
1050 	nilfs_sysfs_delete_mounted_snapshots_group(nilfs);
1051 	nilfs_sysfs_delete_checkpoints_group(nilfs);
1052 	nilfs_sysfs_delete_segments_group(nilfs);
1053 	nilfs_sysfs_delete_superblock_group(nilfs);
1054 	nilfs_sysfs_delete_segctor_group(nilfs);
1055 	kobject_del(&nilfs->ns_dev_kobj);
1056 	kfree(nilfs->ns_dev_subgroups);
1057 }
1058 
1059 /************************************************************************
1060  *                        NILFS feature attrs                           *
1061  ************************************************************************/
1062 
1063 static ssize_t nilfs_feature_revision_show(struct kobject *kobj,
1064 					    struct attribute *attr, char *buf)
1065 {
1066 	return snprintf(buf, PAGE_SIZE, "%d.%d\n",
1067 			NILFS_CURRENT_REV, NILFS_MINOR_REV);
1068 }
1069 
1070 static const char features_readme_str[] =
1071 	"The features group contains attributes that describe NILFS file\n"
1072 	"system driver features.\n\n"
1073 	"(1) revision\n\tshow current revision of NILFS file system driver.\n";
1074 
1075 static ssize_t nilfs_feature_README_show(struct kobject *kobj,
1076 					 struct attribute *attr,
1077 					 char *buf)
1078 {
1079 	return snprintf(buf, PAGE_SIZE, features_readme_str);
1080 }
1081 
1082 NILFS_FEATURE_RO_ATTR(revision);
1083 NILFS_FEATURE_RO_ATTR(README);
1084 
1085 static struct attribute *nilfs_feature_attrs[] = {
1086 	NILFS_FEATURE_ATTR_LIST(revision),
1087 	NILFS_FEATURE_ATTR_LIST(README),
1088 	NULL,
1089 };
1090 
1091 static const struct attribute_group nilfs_feature_attr_group = {
1092 	.name = "features",
1093 	.attrs = nilfs_feature_attrs,
1094 };
1095 
1096 int __init nilfs_sysfs_init(void)
1097 {
1098 	int err;
1099 
1100 	nilfs_kset = kset_create_and_add(NILFS_ROOT_GROUP_NAME, NULL, fs_kobj);
1101 	if (!nilfs_kset) {
1102 		err = -ENOMEM;
1103 		nilfs_err(NULL, "unable to create sysfs entry: err=%d", err);
1104 		goto failed_sysfs_init;
1105 	}
1106 
1107 	err = sysfs_create_group(&nilfs_kset->kobj, &nilfs_feature_attr_group);
1108 	if (unlikely(err)) {
1109 		nilfs_err(NULL, "unable to create feature group: err=%d", err);
1110 		goto cleanup_sysfs_init;
1111 	}
1112 
1113 	return 0;
1114 
1115 cleanup_sysfs_init:
1116 	kset_unregister(nilfs_kset);
1117 
1118 failed_sysfs_init:
1119 	return err;
1120 }
1121 
1122 void nilfs_sysfs_exit(void)
1123 {
1124 	sysfs_remove_group(&nilfs_kset->kobj, &nilfs_feature_attr_group);
1125 	kset_unregister(nilfs_kset);
1126 }
1127