Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / fs / nilfs2 / sysfs.c
1 /*
2  * sysfs.c - sysfs support implementation.
3  *
4  * Copyright (C) 2005-2014 Nippon Telegraph and Telephone Corporation.
5  * Copyright (C) 2014 HGST, Inc., a Western Digital Company.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * Written by Vyacheslav Dubeyko <Vyacheslav.Dubeyko@hgst.com>
18  */
19
20 #include <linux/kobject.h>
21
22 #include "nilfs.h"
23 #include "mdt.h"
24 #include "sufile.h"
25 #include "cpfile.h"
26 #include "sysfs.h"
27
28 /* /sys/fs/<nilfs>/ */
29 static struct kset *nilfs_kset;
30
31 #define NILFS_SHOW_TIME(time_t_val, buf) ({ \
32                 struct tm res; \
33                 int count = 0; \
34                 time_to_tm(time_t_val, 0, &res); \
35                 res.tm_year += 1900; \
36                 res.tm_mon += 1; \
37                 count = scnprintf(buf, PAGE_SIZE, \
38                                     "%ld-%.2d-%.2d %.2d:%.2d:%.2d\n", \
39                                     res.tm_year, res.tm_mon, res.tm_mday, \
40                                     res.tm_hour, res.tm_min, res.tm_sec);\
41                 count; \
42 })
43
44 #define NILFS_DEV_INT_GROUP_OPS(name, parent_name) \
45 static ssize_t nilfs_##name##_attr_show(struct kobject *kobj, \
46                                         struct attribute *attr, char *buf) \
47 { \
48         struct the_nilfs *nilfs = container_of(kobj->parent, \
49                                                 struct the_nilfs, \
50                                                 ns_##parent_name##_kobj); \
51         struct nilfs_##name##_attr *a = container_of(attr, \
52                                                 struct nilfs_##name##_attr, \
53                                                 attr); \
54         return a->show ? a->show(a, nilfs, buf) : 0; \
55 } \
56 static ssize_t nilfs_##name##_attr_store(struct kobject *kobj, \
57                                          struct attribute *attr, \
58                                          const char *buf, size_t len) \
59 { \
60         struct the_nilfs *nilfs = container_of(kobj->parent, \
61                                                 struct the_nilfs, \
62                                                 ns_##parent_name##_kobj); \
63         struct nilfs_##name##_attr *a = container_of(attr, \
64                                                 struct nilfs_##name##_attr, \
65                                                 attr); \
66         return a->store ? a->store(a, nilfs, buf, len) : 0; \
67 } \
68 static const struct sysfs_ops nilfs_##name##_attr_ops = { \
69         .show   = nilfs_##name##_attr_show, \
70         .store  = nilfs_##name##_attr_store, \
71 };
72
73 #define NILFS_DEV_INT_GROUP_TYPE(name, parent_name) \
74 static void nilfs_##name##_attr_release(struct kobject *kobj) \
75 { \
76         struct nilfs_sysfs_##parent_name##_subgroups *subgroups; \
77         struct the_nilfs *nilfs = container_of(kobj->parent, \
78                                                 struct the_nilfs, \
79                                                 ns_##parent_name##_kobj); \
80         subgroups = nilfs->ns_##parent_name##_subgroups; \
81         complete(&subgroups->sg_##name##_kobj_unregister); \
82 } \
83 static struct kobj_type nilfs_##name##_ktype = { \
84         .default_attrs  = nilfs_##name##_attrs, \
85         .sysfs_ops      = &nilfs_##name##_attr_ops, \
86         .release        = nilfs_##name##_attr_release, \
87 };
88
89 #define NILFS_DEV_INT_GROUP_FNS(name, parent_name) \
90 static int nilfs_sysfs_create_##name##_group(struct the_nilfs *nilfs) \
91 { \
92         struct kobject *parent; \
93         struct kobject *kobj; \
94         struct completion *kobj_unregister; \
95         struct nilfs_sysfs_##parent_name##_subgroups *subgroups; \
96         int err; \
97         subgroups = nilfs->ns_##parent_name##_subgroups; \
98         kobj = &subgroups->sg_##name##_kobj; \
99         kobj_unregister = &subgroups->sg_##name##_kobj_unregister; \
100         parent = &nilfs->ns_##parent_name##_kobj; \
101         kobj->kset = nilfs_kset; \
102         init_completion(kobj_unregister); \
103         err = kobject_init_and_add(kobj, &nilfs_##name##_ktype, parent, \
104                                     #name); \
105         if (err) \
106                 return err; \
107         return 0; \
108 } \
109 static void nilfs_sysfs_delete_##name##_group(struct the_nilfs *nilfs) \
110 { \
111         kobject_del(&nilfs->ns_##parent_name##_subgroups->sg_##name##_kobj); \
112 }
113
114 /************************************************************************
115  *                        NILFS snapshot attrs                          *
116  ************************************************************************/
117
118 static ssize_t
119 nilfs_snapshot_inodes_count_show(struct nilfs_snapshot_attr *attr,
120                                  struct nilfs_root *root, char *buf)
121 {
122         return snprintf(buf, PAGE_SIZE, "%llu\n",
123                         (unsigned long long)atomic64_read(&root->inodes_count));
124 }
125
126 static ssize_t
127 nilfs_snapshot_blocks_count_show(struct nilfs_snapshot_attr *attr,
128                                  struct nilfs_root *root, char *buf)
129 {
130         return snprintf(buf, PAGE_SIZE, "%llu\n",
131                         (unsigned long long)atomic64_read(&root->blocks_count));
132 }
133
134 static const char snapshot_readme_str[] =
135         "The group contains details about mounted snapshot.\n\n"
136         "(1) inodes_count\n\tshow number of inodes for snapshot.\n\n"
137         "(2) blocks_count\n\tshow number of blocks for snapshot.\n\n";
138
139 static ssize_t
140 nilfs_snapshot_README_show(struct nilfs_snapshot_attr *attr,
141                             struct nilfs_root *root, char *buf)
142 {
143         return snprintf(buf, PAGE_SIZE, snapshot_readme_str);
144 }
145
146 NILFS_SNAPSHOT_RO_ATTR(inodes_count);
147 NILFS_SNAPSHOT_RO_ATTR(blocks_count);
148 NILFS_SNAPSHOT_RO_ATTR(README);
149
150 static struct attribute *nilfs_snapshot_attrs[] = {
151         NILFS_SNAPSHOT_ATTR_LIST(inodes_count),
152         NILFS_SNAPSHOT_ATTR_LIST(blocks_count),
153         NILFS_SNAPSHOT_ATTR_LIST(README),
154         NULL,
155 };
156
157 static ssize_t nilfs_snapshot_attr_show(struct kobject *kobj,
158                                         struct attribute *attr, char *buf)
159 {
160         struct nilfs_root *root =
161                         container_of(kobj, struct nilfs_root, snapshot_kobj);
162         struct nilfs_snapshot_attr *a =
163                         container_of(attr, struct nilfs_snapshot_attr, attr);
164
165         return a->show ? a->show(a, root, buf) : 0;
166 }
167
168 static ssize_t nilfs_snapshot_attr_store(struct kobject *kobj,
169                                          struct attribute *attr,
170                                          const char *buf, size_t len)
171 {
172         struct nilfs_root *root =
173                         container_of(kobj, struct nilfs_root, snapshot_kobj);
174         struct nilfs_snapshot_attr *a =
175                         container_of(attr, struct nilfs_snapshot_attr, attr);
176
177         return a->store ? a->store(a, root, buf, len) : 0;
178 }
179
180 static void nilfs_snapshot_attr_release(struct kobject *kobj)
181 {
182         struct nilfs_root *root = container_of(kobj, struct nilfs_root,
183                                                 snapshot_kobj);
184         complete(&root->snapshot_kobj_unregister);
185 }
186
187 static const struct sysfs_ops nilfs_snapshot_attr_ops = {
188         .show   = nilfs_snapshot_attr_show,
189         .store  = nilfs_snapshot_attr_store,
190 };
191
192 static struct kobj_type nilfs_snapshot_ktype = {
193         .default_attrs  = nilfs_snapshot_attrs,
194         .sysfs_ops      = &nilfs_snapshot_attr_ops,
195         .release        = nilfs_snapshot_attr_release,
196 };
197
198 int nilfs_sysfs_create_snapshot_group(struct nilfs_root *root)
199 {
200         struct the_nilfs *nilfs;
201         struct kobject *parent;
202         int err;
203
204         nilfs = root->nilfs;
205         parent = &nilfs->ns_dev_subgroups->sg_mounted_snapshots_kobj;
206         root->snapshot_kobj.kset = nilfs_kset;
207         init_completion(&root->snapshot_kobj_unregister);
208
209         if (root->cno == NILFS_CPTREE_CURRENT_CNO) {
210                 err = kobject_init_and_add(&root->snapshot_kobj,
211                                             &nilfs_snapshot_ktype,
212                                             &nilfs->ns_dev_kobj,
213                                             "current_checkpoint");
214         } else {
215                 err = kobject_init_and_add(&root->snapshot_kobj,
216                                             &nilfs_snapshot_ktype,
217                                             parent,
218                                             "%llu", root->cno);
219         }
220
221         if (err)
222                 return err;
223
224         return 0;
225 }
226
227 void nilfs_sysfs_delete_snapshot_group(struct nilfs_root *root)
228 {
229         kobject_del(&root->snapshot_kobj);
230 }
231
232 /************************************************************************
233  *                    NILFS mounted snapshots attrs                     *
234  ************************************************************************/
235
236 static const char mounted_snapshots_readme_str[] =
237         "The mounted_snapshots group contains group for\n"
238         "every mounted snapshot.\n";
239
240 static ssize_t
241 nilfs_mounted_snapshots_README_show(struct nilfs_mounted_snapshots_attr *attr,
242                                     struct the_nilfs *nilfs, char *buf)
243 {
244         return snprintf(buf, PAGE_SIZE, mounted_snapshots_readme_str);
245 }
246
247 NILFS_MOUNTED_SNAPSHOTS_RO_ATTR(README);
248
249 static struct attribute *nilfs_mounted_snapshots_attrs[] = {
250         NILFS_MOUNTED_SNAPSHOTS_ATTR_LIST(README),
251         NULL,
252 };
253
254 NILFS_DEV_INT_GROUP_OPS(mounted_snapshots, dev);
255 NILFS_DEV_INT_GROUP_TYPE(mounted_snapshots, dev);
256 NILFS_DEV_INT_GROUP_FNS(mounted_snapshots, dev);
257
258 /************************************************************************
259  *                      NILFS checkpoints attrs                         *
260  ************************************************************************/
261
262 static ssize_t
263 nilfs_checkpoints_checkpoints_number_show(struct nilfs_checkpoints_attr *attr,
264                                             struct the_nilfs *nilfs,
265                                             char *buf)
266 {
267         __u64 ncheckpoints;
268         struct nilfs_cpstat cpstat;
269         int err;
270
271         down_read(&nilfs->ns_segctor_sem);
272         err = nilfs_cpfile_get_stat(nilfs->ns_cpfile, &cpstat);
273         up_read(&nilfs->ns_segctor_sem);
274         if (err < 0) {
275                 printk(KERN_ERR "NILFS: unable to get checkpoint stat: err=%d\n",
276                         err);
277                 return err;
278         }
279
280         ncheckpoints = cpstat.cs_ncps;
281
282         return snprintf(buf, PAGE_SIZE, "%llu\n", ncheckpoints);
283 }
284
285 static ssize_t
286 nilfs_checkpoints_snapshots_number_show(struct nilfs_checkpoints_attr *attr,
287                                         struct the_nilfs *nilfs,
288                                         char *buf)
289 {
290         __u64 nsnapshots;
291         struct nilfs_cpstat cpstat;
292         int err;
293
294         down_read(&nilfs->ns_segctor_sem);
295         err = nilfs_cpfile_get_stat(nilfs->ns_cpfile, &cpstat);
296         up_read(&nilfs->ns_segctor_sem);
297         if (err < 0) {
298                 printk(KERN_ERR "NILFS: unable to get checkpoint stat: err=%d\n",
299                         err);
300                 return err;
301         }
302
303         nsnapshots = cpstat.cs_nsss;
304
305         return snprintf(buf, PAGE_SIZE, "%llu\n", nsnapshots);
306 }
307
308 static ssize_t
309 nilfs_checkpoints_last_seg_checkpoint_show(struct nilfs_checkpoints_attr *attr,
310                                             struct the_nilfs *nilfs,
311                                             char *buf)
312 {
313         __u64 last_cno;
314
315         spin_lock(&nilfs->ns_last_segment_lock);
316         last_cno = nilfs->ns_last_cno;
317         spin_unlock(&nilfs->ns_last_segment_lock);
318
319         return snprintf(buf, PAGE_SIZE, "%llu\n", last_cno);
320 }
321
322 static ssize_t
323 nilfs_checkpoints_next_checkpoint_show(struct nilfs_checkpoints_attr *attr,
324                                         struct the_nilfs *nilfs,
325                                         char *buf)
326 {
327         __u64 cno;
328
329         down_read(&nilfs->ns_sem);
330         cno = nilfs->ns_cno;
331         up_read(&nilfs->ns_sem);
332
333         return snprintf(buf, PAGE_SIZE, "%llu\n", cno);
334 }
335
336 static const char checkpoints_readme_str[] =
337         "The checkpoints group contains attributes that describe\n"
338         "details about volume's checkpoints.\n\n"
339         "(1) checkpoints_number\n\tshow number of checkpoints on volume.\n\n"
340         "(2) snapshots_number\n\tshow number of snapshots on volume.\n\n"
341         "(3) last_seg_checkpoint\n"
342         "\tshow checkpoint number of the latest segment.\n\n"
343         "(4) next_checkpoint\n\tshow next checkpoint number.\n\n";
344
345 static ssize_t
346 nilfs_checkpoints_README_show(struct nilfs_checkpoints_attr *attr,
347                                 struct the_nilfs *nilfs, char *buf)
348 {
349         return snprintf(buf, PAGE_SIZE, checkpoints_readme_str);
350 }
351
352 NILFS_CHECKPOINTS_RO_ATTR(checkpoints_number);
353 NILFS_CHECKPOINTS_RO_ATTR(snapshots_number);
354 NILFS_CHECKPOINTS_RO_ATTR(last_seg_checkpoint);
355 NILFS_CHECKPOINTS_RO_ATTR(next_checkpoint);
356 NILFS_CHECKPOINTS_RO_ATTR(README);
357
358 static struct attribute *nilfs_checkpoints_attrs[] = {
359         NILFS_CHECKPOINTS_ATTR_LIST(checkpoints_number),
360         NILFS_CHECKPOINTS_ATTR_LIST(snapshots_number),
361         NILFS_CHECKPOINTS_ATTR_LIST(last_seg_checkpoint),
362         NILFS_CHECKPOINTS_ATTR_LIST(next_checkpoint),
363         NILFS_CHECKPOINTS_ATTR_LIST(README),
364         NULL,
365 };
366
367 NILFS_DEV_INT_GROUP_OPS(checkpoints, dev);
368 NILFS_DEV_INT_GROUP_TYPE(checkpoints, dev);
369 NILFS_DEV_INT_GROUP_FNS(checkpoints, dev);
370
371 /************************************************************************
372  *                        NILFS segments attrs                          *
373  ************************************************************************/
374
375 static ssize_t
376 nilfs_segments_segments_number_show(struct nilfs_segments_attr *attr,
377                                      struct the_nilfs *nilfs,
378                                      char *buf)
379 {
380         return snprintf(buf, PAGE_SIZE, "%lu\n", nilfs->ns_nsegments);
381 }
382
383 static ssize_t
384 nilfs_segments_blocks_per_segment_show(struct nilfs_segments_attr *attr,
385                                         struct the_nilfs *nilfs,
386                                         char *buf)
387 {
388         return snprintf(buf, PAGE_SIZE, "%lu\n", nilfs->ns_blocks_per_segment);
389 }
390
391 static ssize_t
392 nilfs_segments_clean_segments_show(struct nilfs_segments_attr *attr,
393                                     struct the_nilfs *nilfs,
394                                     char *buf)
395 {
396         unsigned long ncleansegs;
397
398         down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
399         ncleansegs = nilfs_sufile_get_ncleansegs(nilfs->ns_sufile);
400         up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
401
402         return snprintf(buf, PAGE_SIZE, "%lu\n", ncleansegs);
403 }
404
405 static ssize_t
406 nilfs_segments_dirty_segments_show(struct nilfs_segments_attr *attr,
407                                     struct the_nilfs *nilfs,
408                                     char *buf)
409 {
410         struct nilfs_sustat sustat;
411         int err;
412
413         down_read(&nilfs->ns_segctor_sem);
414         err = nilfs_sufile_get_stat(nilfs->ns_sufile, &sustat);
415         up_read(&nilfs->ns_segctor_sem);
416         if (err < 0) {
417                 printk(KERN_ERR "NILFS: unable to get segment stat: err=%d\n",
418                         err);
419                 return err;
420         }
421
422         return snprintf(buf, PAGE_SIZE, "%llu\n", sustat.ss_ndirtysegs);
423 }
424
425 static const char segments_readme_str[] =
426         "The segments group contains attributes that describe\n"
427         "details about volume's segments.\n\n"
428         "(1) segments_number\n\tshow number of segments on volume.\n\n"
429         "(2) blocks_per_segment\n\tshow number of blocks in segment.\n\n"
430         "(3) clean_segments\n\tshow count of clean segments.\n\n"
431         "(4) dirty_segments\n\tshow count of dirty segments.\n\n";
432
433 static ssize_t
434 nilfs_segments_README_show(struct nilfs_segments_attr *attr,
435                             struct the_nilfs *nilfs,
436                             char *buf)
437 {
438         return snprintf(buf, PAGE_SIZE, segments_readme_str);
439 }
440
441 NILFS_SEGMENTS_RO_ATTR(segments_number);
442 NILFS_SEGMENTS_RO_ATTR(blocks_per_segment);
443 NILFS_SEGMENTS_RO_ATTR(clean_segments);
444 NILFS_SEGMENTS_RO_ATTR(dirty_segments);
445 NILFS_SEGMENTS_RO_ATTR(README);
446
447 static struct attribute *nilfs_segments_attrs[] = {
448         NILFS_SEGMENTS_ATTR_LIST(segments_number),
449         NILFS_SEGMENTS_ATTR_LIST(blocks_per_segment),
450         NILFS_SEGMENTS_ATTR_LIST(clean_segments),
451         NILFS_SEGMENTS_ATTR_LIST(dirty_segments),
452         NILFS_SEGMENTS_ATTR_LIST(README),
453         NULL,
454 };
455
456 NILFS_DEV_INT_GROUP_OPS(segments, dev);
457 NILFS_DEV_INT_GROUP_TYPE(segments, dev);
458 NILFS_DEV_INT_GROUP_FNS(segments, dev);
459
460 /************************************************************************
461  *                        NILFS segctor attrs                           *
462  ************************************************************************/
463
464 static ssize_t
465 nilfs_segctor_last_pseg_block_show(struct nilfs_segctor_attr *attr,
466                                     struct the_nilfs *nilfs,
467                                     char *buf)
468 {
469         sector_t last_pseg;
470
471         spin_lock(&nilfs->ns_last_segment_lock);
472         last_pseg = nilfs->ns_last_pseg;
473         spin_unlock(&nilfs->ns_last_segment_lock);
474
475         return snprintf(buf, PAGE_SIZE, "%llu\n",
476                         (unsigned long long)last_pseg);
477 }
478
479 static ssize_t
480 nilfs_segctor_last_seg_sequence_show(struct nilfs_segctor_attr *attr,
481                                         struct the_nilfs *nilfs,
482                                         char *buf)
483 {
484         u64 last_seq;
485
486         spin_lock(&nilfs->ns_last_segment_lock);
487         last_seq = nilfs->ns_last_seq;
488         spin_unlock(&nilfs->ns_last_segment_lock);
489
490         return snprintf(buf, PAGE_SIZE, "%llu\n", last_seq);
491 }
492
493 static ssize_t
494 nilfs_segctor_last_seg_checkpoint_show(struct nilfs_segctor_attr *attr,
495                                         struct the_nilfs *nilfs,
496                                         char *buf)
497 {
498         __u64 last_cno;
499
500         spin_lock(&nilfs->ns_last_segment_lock);
501         last_cno = nilfs->ns_last_cno;
502         spin_unlock(&nilfs->ns_last_segment_lock);
503
504         return snprintf(buf, PAGE_SIZE, "%llu\n", last_cno);
505 }
506
507 static ssize_t
508 nilfs_segctor_current_seg_sequence_show(struct nilfs_segctor_attr *attr,
509                                         struct the_nilfs *nilfs,
510                                         char *buf)
511 {
512         u64 seg_seq;
513
514         down_read(&nilfs->ns_sem);
515         seg_seq = nilfs->ns_seg_seq;
516         up_read(&nilfs->ns_sem);
517
518         return snprintf(buf, PAGE_SIZE, "%llu\n", seg_seq);
519 }
520
521 static ssize_t
522 nilfs_segctor_current_last_full_seg_show(struct nilfs_segctor_attr *attr,
523                                          struct the_nilfs *nilfs,
524                                          char *buf)
525 {
526         __u64 segnum;
527
528         down_read(&nilfs->ns_sem);
529         segnum = nilfs->ns_segnum;
530         up_read(&nilfs->ns_sem);
531
532         return snprintf(buf, PAGE_SIZE, "%llu\n", segnum);
533 }
534
535 static ssize_t
536 nilfs_segctor_next_full_seg_show(struct nilfs_segctor_attr *attr,
537                                  struct the_nilfs *nilfs,
538                                  char *buf)
539 {
540         __u64 nextnum;
541
542         down_read(&nilfs->ns_sem);
543         nextnum = nilfs->ns_nextnum;
544         up_read(&nilfs->ns_sem);
545
546         return snprintf(buf, PAGE_SIZE, "%llu\n", nextnum);
547 }
548
549 static ssize_t
550 nilfs_segctor_next_pseg_offset_show(struct nilfs_segctor_attr *attr,
551                                         struct the_nilfs *nilfs,
552                                         char *buf)
553 {
554         unsigned long pseg_offset;
555
556         down_read(&nilfs->ns_sem);
557         pseg_offset = nilfs->ns_pseg_offset;
558         up_read(&nilfs->ns_sem);
559
560         return snprintf(buf, PAGE_SIZE, "%lu\n", pseg_offset);
561 }
562
563 static ssize_t
564 nilfs_segctor_next_checkpoint_show(struct nilfs_segctor_attr *attr,
565                                         struct the_nilfs *nilfs,
566                                         char *buf)
567 {
568         __u64 cno;
569
570         down_read(&nilfs->ns_sem);
571         cno = nilfs->ns_cno;
572         up_read(&nilfs->ns_sem);
573
574         return snprintf(buf, PAGE_SIZE, "%llu\n", cno);
575 }
576
577 static ssize_t
578 nilfs_segctor_last_seg_write_time_show(struct nilfs_segctor_attr *attr,
579                                         struct the_nilfs *nilfs,
580                                         char *buf)
581 {
582         time_t ctime;
583
584         down_read(&nilfs->ns_sem);
585         ctime = nilfs->ns_ctime;
586         up_read(&nilfs->ns_sem);
587
588         return NILFS_SHOW_TIME(ctime, buf);
589 }
590
591 static ssize_t
592 nilfs_segctor_last_seg_write_time_secs_show(struct nilfs_segctor_attr *attr,
593                                             struct the_nilfs *nilfs,
594                                             char *buf)
595 {
596         time_t ctime;
597
598         down_read(&nilfs->ns_sem);
599         ctime = nilfs->ns_ctime;
600         up_read(&nilfs->ns_sem);
601
602         return snprintf(buf, PAGE_SIZE, "%llu\n", (unsigned long long)ctime);
603 }
604
605 static ssize_t
606 nilfs_segctor_last_nongc_write_time_show(struct nilfs_segctor_attr *attr,
607                                          struct the_nilfs *nilfs,
608                                          char *buf)
609 {
610         time_t nongc_ctime;
611
612         down_read(&nilfs->ns_sem);
613         nongc_ctime = nilfs->ns_nongc_ctime;
614         up_read(&nilfs->ns_sem);
615
616         return NILFS_SHOW_TIME(nongc_ctime, buf);
617 }
618
619 static ssize_t
620 nilfs_segctor_last_nongc_write_time_secs_show(struct nilfs_segctor_attr *attr,
621                                                 struct the_nilfs *nilfs,
622                                                 char *buf)
623 {
624         time_t nongc_ctime;
625
626         down_read(&nilfs->ns_sem);
627         nongc_ctime = nilfs->ns_nongc_ctime;
628         up_read(&nilfs->ns_sem);
629
630         return snprintf(buf, PAGE_SIZE, "%llu\n",
631                         (unsigned long long)nongc_ctime);
632 }
633
634 static ssize_t
635 nilfs_segctor_dirty_data_blocks_count_show(struct nilfs_segctor_attr *attr,
636                                             struct the_nilfs *nilfs,
637                                             char *buf)
638 {
639         u32 ndirtyblks;
640
641         down_read(&nilfs->ns_sem);
642         ndirtyblks = atomic_read(&nilfs->ns_ndirtyblks);
643         up_read(&nilfs->ns_sem);
644
645         return snprintf(buf, PAGE_SIZE, "%u\n", ndirtyblks);
646 }
647
648 static const char segctor_readme_str[] =
649         "The segctor group contains attributes that describe\n"
650         "segctor thread activity details.\n\n"
651         "(1) last_pseg_block\n"
652         "\tshow start block number of the latest segment.\n\n"
653         "(2) last_seg_sequence\n"
654         "\tshow sequence value of the latest segment.\n\n"
655         "(3) last_seg_checkpoint\n"
656         "\tshow checkpoint number of the latest segment.\n\n"
657         "(4) current_seg_sequence\n\tshow segment sequence counter.\n\n"
658         "(5) current_last_full_seg\n"
659         "\tshow index number of the latest full segment.\n\n"
660         "(6) next_full_seg\n"
661         "\tshow index number of the full segment index to be used next.\n\n"
662         "(7) next_pseg_offset\n"
663         "\tshow offset of next partial segment in the current full segment.\n\n"
664         "(8) next_checkpoint\n\tshow next checkpoint number.\n\n"
665         "(9) last_seg_write_time\n"
666         "\tshow write time of the last segment in human-readable format.\n\n"
667         "(10) last_seg_write_time_secs\n"
668         "\tshow write time of the last segment in seconds.\n\n"
669         "(11) last_nongc_write_time\n"
670         "\tshow write time of the last segment not for cleaner operation "
671         "in human-readable format.\n\n"
672         "(12) last_nongc_write_time_secs\n"
673         "\tshow write time of the last segment not for cleaner operation "
674         "in seconds.\n\n"
675         "(13) dirty_data_blocks_count\n"
676         "\tshow number of dirty data blocks.\n\n";
677
678 static ssize_t
679 nilfs_segctor_README_show(struct nilfs_segctor_attr *attr,
680                           struct the_nilfs *nilfs, char *buf)
681 {
682         return snprintf(buf, PAGE_SIZE, segctor_readme_str);
683 }
684
685 NILFS_SEGCTOR_RO_ATTR(last_pseg_block);
686 NILFS_SEGCTOR_RO_ATTR(last_seg_sequence);
687 NILFS_SEGCTOR_RO_ATTR(last_seg_checkpoint);
688 NILFS_SEGCTOR_RO_ATTR(current_seg_sequence);
689 NILFS_SEGCTOR_RO_ATTR(current_last_full_seg);
690 NILFS_SEGCTOR_RO_ATTR(next_full_seg);
691 NILFS_SEGCTOR_RO_ATTR(next_pseg_offset);
692 NILFS_SEGCTOR_RO_ATTR(next_checkpoint);
693 NILFS_SEGCTOR_RO_ATTR(last_seg_write_time);
694 NILFS_SEGCTOR_RO_ATTR(last_seg_write_time_secs);
695 NILFS_SEGCTOR_RO_ATTR(last_nongc_write_time);
696 NILFS_SEGCTOR_RO_ATTR(last_nongc_write_time_secs);
697 NILFS_SEGCTOR_RO_ATTR(dirty_data_blocks_count);
698 NILFS_SEGCTOR_RO_ATTR(README);
699
700 static struct attribute *nilfs_segctor_attrs[] = {
701         NILFS_SEGCTOR_ATTR_LIST(last_pseg_block),
702         NILFS_SEGCTOR_ATTR_LIST(last_seg_sequence),
703         NILFS_SEGCTOR_ATTR_LIST(last_seg_checkpoint),
704         NILFS_SEGCTOR_ATTR_LIST(current_seg_sequence),
705         NILFS_SEGCTOR_ATTR_LIST(current_last_full_seg),
706         NILFS_SEGCTOR_ATTR_LIST(next_full_seg),
707         NILFS_SEGCTOR_ATTR_LIST(next_pseg_offset),
708         NILFS_SEGCTOR_ATTR_LIST(next_checkpoint),
709         NILFS_SEGCTOR_ATTR_LIST(last_seg_write_time),
710         NILFS_SEGCTOR_ATTR_LIST(last_seg_write_time_secs),
711         NILFS_SEGCTOR_ATTR_LIST(last_nongc_write_time),
712         NILFS_SEGCTOR_ATTR_LIST(last_nongc_write_time_secs),
713         NILFS_SEGCTOR_ATTR_LIST(dirty_data_blocks_count),
714         NILFS_SEGCTOR_ATTR_LIST(README),
715         NULL,
716 };
717
718 NILFS_DEV_INT_GROUP_OPS(segctor, dev);
719 NILFS_DEV_INT_GROUP_TYPE(segctor, dev);
720 NILFS_DEV_INT_GROUP_FNS(segctor, dev);
721
722 /************************************************************************
723  *                        NILFS superblock attrs                        *
724  ************************************************************************/
725
726 static ssize_t
727 nilfs_superblock_sb_write_time_show(struct nilfs_superblock_attr *attr,
728                                      struct the_nilfs *nilfs,
729                                      char *buf)
730 {
731         time_t sbwtime;
732
733         down_read(&nilfs->ns_sem);
734         sbwtime = nilfs->ns_sbwtime;
735         up_read(&nilfs->ns_sem);
736
737         return NILFS_SHOW_TIME(sbwtime, buf);
738 }
739
740 static ssize_t
741 nilfs_superblock_sb_write_time_secs_show(struct nilfs_superblock_attr *attr,
742                                          struct the_nilfs *nilfs,
743                                          char *buf)
744 {
745         time_t sbwtime;
746
747         down_read(&nilfs->ns_sem);
748         sbwtime = nilfs->ns_sbwtime;
749         up_read(&nilfs->ns_sem);
750
751         return snprintf(buf, PAGE_SIZE, "%llu\n", (unsigned long long)sbwtime);
752 }
753
754 static ssize_t
755 nilfs_superblock_sb_write_count_show(struct nilfs_superblock_attr *attr,
756                                       struct the_nilfs *nilfs,
757                                       char *buf)
758 {
759         unsigned sbwcount;
760
761         down_read(&nilfs->ns_sem);
762         sbwcount = nilfs->ns_sbwcount;
763         up_read(&nilfs->ns_sem);
764
765         return snprintf(buf, PAGE_SIZE, "%u\n", sbwcount);
766 }
767
768 static ssize_t
769 nilfs_superblock_sb_update_frequency_show(struct nilfs_superblock_attr *attr,
770                                             struct the_nilfs *nilfs,
771                                             char *buf)
772 {
773         unsigned sb_update_freq;
774
775         down_read(&nilfs->ns_sem);
776         sb_update_freq = nilfs->ns_sb_update_freq;
777         up_read(&nilfs->ns_sem);
778
779         return snprintf(buf, PAGE_SIZE, "%u\n", sb_update_freq);
780 }
781
782 static ssize_t
783 nilfs_superblock_sb_update_frequency_store(struct nilfs_superblock_attr *attr,
784                                             struct the_nilfs *nilfs,
785                                             const char *buf, size_t count)
786 {
787         unsigned val;
788         int err;
789
790         err = kstrtouint(skip_spaces(buf), 0, &val);
791         if (err) {
792                 printk(KERN_ERR "NILFS: unable to convert string: err=%d\n",
793                         err);
794                 return err;
795         }
796
797         if (val < NILFS_SB_FREQ) {
798                 val = NILFS_SB_FREQ;
799                 printk(KERN_WARNING "NILFS: superblock update frequency cannot be lesser than 10 seconds\n");
800         }
801
802         down_write(&nilfs->ns_sem);
803         nilfs->ns_sb_update_freq = val;
804         up_write(&nilfs->ns_sem);
805
806         return count;
807 }
808
809 static const char sb_readme_str[] =
810         "The superblock group contains attributes that describe\n"
811         "superblock's details.\n\n"
812         "(1) sb_write_time\n\tshow previous write time of super block "
813         "in human-readable format.\n\n"
814         "(2) sb_write_time_secs\n\tshow previous write time of super block "
815         "in seconds.\n\n"
816         "(3) sb_write_count\n\tshow write count of super block.\n\n"
817         "(4) sb_update_frequency\n"
818         "\tshow/set interval of periodical update of superblock (in seconds).\n\n"
819         "\tYou can set preferable frequency of superblock update by command:\n\n"
820         "\t'echo <val> > /sys/fs/<nilfs>/<dev>/superblock/sb_update_frequency'\n";
821
822 static ssize_t
823 nilfs_superblock_README_show(struct nilfs_superblock_attr *attr,
824                                 struct the_nilfs *nilfs, char *buf)
825 {
826         return snprintf(buf, PAGE_SIZE, sb_readme_str);
827 }
828
829 NILFS_SUPERBLOCK_RO_ATTR(sb_write_time);
830 NILFS_SUPERBLOCK_RO_ATTR(sb_write_time_secs);
831 NILFS_SUPERBLOCK_RO_ATTR(sb_write_count);
832 NILFS_SUPERBLOCK_RW_ATTR(sb_update_frequency);
833 NILFS_SUPERBLOCK_RO_ATTR(README);
834
835 static struct attribute *nilfs_superblock_attrs[] = {
836         NILFS_SUPERBLOCK_ATTR_LIST(sb_write_time),
837         NILFS_SUPERBLOCK_ATTR_LIST(sb_write_time_secs),
838         NILFS_SUPERBLOCK_ATTR_LIST(sb_write_count),
839         NILFS_SUPERBLOCK_ATTR_LIST(sb_update_frequency),
840         NILFS_SUPERBLOCK_ATTR_LIST(README),
841         NULL,
842 };
843
844 NILFS_DEV_INT_GROUP_OPS(superblock, dev);
845 NILFS_DEV_INT_GROUP_TYPE(superblock, dev);
846 NILFS_DEV_INT_GROUP_FNS(superblock, dev);
847
848 /************************************************************************
849  *                        NILFS device attrs                            *
850  ************************************************************************/
851
852 static
853 ssize_t nilfs_dev_revision_show(struct nilfs_dev_attr *attr,
854                                 struct the_nilfs *nilfs,
855                                 char *buf)
856 {
857         struct nilfs_super_block **sbp = nilfs->ns_sbp;
858         u32 major = le32_to_cpu(sbp[0]->s_rev_level);
859         u16 minor = le16_to_cpu(sbp[0]->s_minor_rev_level);
860
861         return snprintf(buf, PAGE_SIZE, "%d.%d\n", major, minor);
862 }
863
864 static
865 ssize_t nilfs_dev_blocksize_show(struct nilfs_dev_attr *attr,
866                                  struct the_nilfs *nilfs,
867                                  char *buf)
868 {
869         return snprintf(buf, PAGE_SIZE, "%u\n", nilfs->ns_blocksize);
870 }
871
872 static
873 ssize_t nilfs_dev_device_size_show(struct nilfs_dev_attr *attr,
874                                     struct the_nilfs *nilfs,
875                                     char *buf)
876 {
877         struct nilfs_super_block **sbp = nilfs->ns_sbp;
878         u64 dev_size = le64_to_cpu(sbp[0]->s_dev_size);
879
880         return snprintf(buf, PAGE_SIZE, "%llu\n", dev_size);
881 }
882
883 static
884 ssize_t nilfs_dev_free_blocks_show(struct nilfs_dev_attr *attr,
885                                    struct the_nilfs *nilfs,
886                                    char *buf)
887 {
888         sector_t free_blocks = 0;
889
890         nilfs_count_free_blocks(nilfs, &free_blocks);
891         return snprintf(buf, PAGE_SIZE, "%llu\n",
892                         (unsigned long long)free_blocks);
893 }
894
895 static
896 ssize_t nilfs_dev_uuid_show(struct nilfs_dev_attr *attr,
897                             struct the_nilfs *nilfs,
898                             char *buf)
899 {
900         struct nilfs_super_block **sbp = nilfs->ns_sbp;
901
902         return snprintf(buf, PAGE_SIZE, "%pUb\n", sbp[0]->s_uuid);
903 }
904
905 static
906 ssize_t nilfs_dev_volume_name_show(struct nilfs_dev_attr *attr,
907                                     struct the_nilfs *nilfs,
908                                     char *buf)
909 {
910         struct nilfs_super_block **sbp = nilfs->ns_sbp;
911
912         return scnprintf(buf, sizeof(sbp[0]->s_volume_name), "%s\n",
913                          sbp[0]->s_volume_name);
914 }
915
916 static const char dev_readme_str[] =
917         "The <device> group contains attributes that describe file system\n"
918         "partition's details.\n\n"
919         "(1) revision\n\tshow NILFS file system revision.\n\n"
920         "(2) blocksize\n\tshow volume block size in bytes.\n\n"
921         "(3) device_size\n\tshow volume size in bytes.\n\n"
922         "(4) free_blocks\n\tshow count of free blocks on volume.\n\n"
923         "(5) uuid\n\tshow volume's UUID.\n\n"
924         "(6) volume_name\n\tshow volume's name.\n\n";
925
926 static ssize_t nilfs_dev_README_show(struct nilfs_dev_attr *attr,
927                                      struct the_nilfs *nilfs,
928                                      char *buf)
929 {
930         return snprintf(buf, PAGE_SIZE, dev_readme_str);
931 }
932
933 NILFS_DEV_RO_ATTR(revision);
934 NILFS_DEV_RO_ATTR(blocksize);
935 NILFS_DEV_RO_ATTR(device_size);
936 NILFS_DEV_RO_ATTR(free_blocks);
937 NILFS_DEV_RO_ATTR(uuid);
938 NILFS_DEV_RO_ATTR(volume_name);
939 NILFS_DEV_RO_ATTR(README);
940
941 static struct attribute *nilfs_dev_attrs[] = {
942         NILFS_DEV_ATTR_LIST(revision),
943         NILFS_DEV_ATTR_LIST(blocksize),
944         NILFS_DEV_ATTR_LIST(device_size),
945         NILFS_DEV_ATTR_LIST(free_blocks),
946         NILFS_DEV_ATTR_LIST(uuid),
947         NILFS_DEV_ATTR_LIST(volume_name),
948         NILFS_DEV_ATTR_LIST(README),
949         NULL,
950 };
951
952 static ssize_t nilfs_dev_attr_show(struct kobject *kobj,
953                                     struct attribute *attr, char *buf)
954 {
955         struct the_nilfs *nilfs = container_of(kobj, struct the_nilfs,
956                                                 ns_dev_kobj);
957         struct nilfs_dev_attr *a = container_of(attr, struct nilfs_dev_attr,
958                                                 attr);
959
960         return a->show ? a->show(a, nilfs, buf) : 0;
961 }
962
963 static ssize_t nilfs_dev_attr_store(struct kobject *kobj,
964                                     struct attribute *attr,
965                                     const char *buf, size_t len)
966 {
967         struct the_nilfs *nilfs = container_of(kobj, struct the_nilfs,
968                                                 ns_dev_kobj);
969         struct nilfs_dev_attr *a = container_of(attr, struct nilfs_dev_attr,
970                                                 attr);
971
972         return a->store ? a->store(a, nilfs, buf, len) : 0;
973 }
974
975 static void nilfs_dev_attr_release(struct kobject *kobj)
976 {
977         struct the_nilfs *nilfs = container_of(kobj, struct the_nilfs,
978                                                 ns_dev_kobj);
979         complete(&nilfs->ns_dev_kobj_unregister);
980 }
981
982 static const struct sysfs_ops nilfs_dev_attr_ops = {
983         .show   = nilfs_dev_attr_show,
984         .store  = nilfs_dev_attr_store,
985 };
986
987 static struct kobj_type nilfs_dev_ktype = {
988         .default_attrs  = nilfs_dev_attrs,
989         .sysfs_ops      = &nilfs_dev_attr_ops,
990         .release        = nilfs_dev_attr_release,
991 };
992
993 int nilfs_sysfs_create_device_group(struct super_block *sb)
994 {
995         struct the_nilfs *nilfs = sb->s_fs_info;
996         size_t devgrp_size = sizeof(struct nilfs_sysfs_dev_subgroups);
997         int err;
998
999         nilfs->ns_dev_subgroups = kzalloc(devgrp_size, GFP_KERNEL);
1000         if (unlikely(!nilfs->ns_dev_subgroups)) {
1001                 err = -ENOMEM;
1002                 printk(KERN_ERR "NILFS: unable to allocate memory for device group\n");
1003                 goto failed_create_device_group;
1004         }
1005
1006         nilfs->ns_dev_kobj.kset = nilfs_kset;
1007         init_completion(&nilfs->ns_dev_kobj_unregister);
1008         err = kobject_init_and_add(&nilfs->ns_dev_kobj, &nilfs_dev_ktype, NULL,
1009                                     "%s", sb->s_id);
1010         if (err)
1011                 goto free_dev_subgroups;
1012
1013         err = nilfs_sysfs_create_mounted_snapshots_group(nilfs);
1014         if (err)
1015                 goto cleanup_dev_kobject;
1016
1017         err = nilfs_sysfs_create_checkpoints_group(nilfs);
1018         if (err)
1019                 goto delete_mounted_snapshots_group;
1020
1021         err = nilfs_sysfs_create_segments_group(nilfs);
1022         if (err)
1023                 goto delete_checkpoints_group;
1024
1025         err = nilfs_sysfs_create_superblock_group(nilfs);
1026         if (err)
1027                 goto delete_segments_group;
1028
1029         err = nilfs_sysfs_create_segctor_group(nilfs);
1030         if (err)
1031                 goto delete_superblock_group;
1032
1033         return 0;
1034
1035 delete_superblock_group:
1036         nilfs_sysfs_delete_superblock_group(nilfs);
1037
1038 delete_segments_group:
1039         nilfs_sysfs_delete_segments_group(nilfs);
1040
1041 delete_checkpoints_group:
1042         nilfs_sysfs_delete_checkpoints_group(nilfs);
1043
1044 delete_mounted_snapshots_group:
1045         nilfs_sysfs_delete_mounted_snapshots_group(nilfs);
1046
1047 cleanup_dev_kobject:
1048         kobject_del(&nilfs->ns_dev_kobj);
1049
1050 free_dev_subgroups:
1051         kfree(nilfs->ns_dev_subgroups);
1052
1053 failed_create_device_group:
1054         return err;
1055 }
1056
1057 void nilfs_sysfs_delete_device_group(struct the_nilfs *nilfs)
1058 {
1059         nilfs_sysfs_delete_mounted_snapshots_group(nilfs);
1060         nilfs_sysfs_delete_checkpoints_group(nilfs);
1061         nilfs_sysfs_delete_segments_group(nilfs);
1062         nilfs_sysfs_delete_superblock_group(nilfs);
1063         nilfs_sysfs_delete_segctor_group(nilfs);
1064         kobject_del(&nilfs->ns_dev_kobj);
1065         kfree(nilfs->ns_dev_subgroups);
1066 }
1067
1068 /************************************************************************
1069  *                        NILFS feature attrs                           *
1070  ************************************************************************/
1071
1072 static ssize_t nilfs_feature_revision_show(struct kobject *kobj,
1073                                             struct attribute *attr, char *buf)
1074 {
1075         return snprintf(buf, PAGE_SIZE, "%d.%d\n",
1076                         NILFS_CURRENT_REV, NILFS_MINOR_REV);
1077 }
1078
1079 static const char features_readme_str[] =
1080         "The features group contains attributes that describe NILFS file\n"
1081         "system driver features.\n\n"
1082         "(1) revision\n\tshow current revision of NILFS file system driver.\n";
1083
1084 static ssize_t nilfs_feature_README_show(struct kobject *kobj,
1085                                          struct attribute *attr,
1086                                          char *buf)
1087 {
1088         return snprintf(buf, PAGE_SIZE, features_readme_str);
1089 }
1090
1091 NILFS_FEATURE_RO_ATTR(revision);
1092 NILFS_FEATURE_RO_ATTR(README);
1093
1094 static struct attribute *nilfs_feature_attrs[] = {
1095         NILFS_FEATURE_ATTR_LIST(revision),
1096         NILFS_FEATURE_ATTR_LIST(README),
1097         NULL,
1098 };
1099
1100 static const struct attribute_group nilfs_feature_attr_group = {
1101         .name = "features",
1102         .attrs = nilfs_feature_attrs,
1103 };
1104
1105 int __init nilfs_sysfs_init(void)
1106 {
1107         int err;
1108
1109         nilfs_kset = kset_create_and_add(NILFS_ROOT_GROUP_NAME, NULL, fs_kobj);
1110         if (!nilfs_kset) {
1111                 err = -ENOMEM;
1112                 printk(KERN_ERR "NILFS: unable to create sysfs entry: err %d\n",
1113                         err);
1114                 goto failed_sysfs_init;
1115         }
1116
1117         err = sysfs_create_group(&nilfs_kset->kobj, &nilfs_feature_attr_group);
1118         if (unlikely(err)) {
1119                 printk(KERN_ERR "NILFS: unable to create feature group: err %d\n",
1120                         err);
1121                 goto cleanup_sysfs_init;
1122         }
1123
1124         return 0;
1125
1126 cleanup_sysfs_init:
1127         kset_unregister(nilfs_kset);
1128
1129 failed_sysfs_init:
1130         return err;
1131 }
1132
1133 void nilfs_sysfs_exit(void)
1134 {
1135         sysfs_remove_group(&nilfs_kset->kobj, &nilfs_feature_attr_group);
1136         kset_unregister(nilfs_kset);
1137 }