1 // SPDX-License-Identifier: GPL-2.0 1
2 /*
3 * linux/fs/ext4/sysfs.c
4 *
5 * Copyright (C) 1992, 1993, 1994, 1995
6 * Remy Card (card@masi.ibp.fr)
7 * Theodore Ts'o (tytso@mit.edu)
8 *
9 */
10
11 #include <linux/time.h>
12 #include <linux/fs.h>
13 #include <linux/seq_file.h>
14 #include <linux/slab.h>
15 #include <linux/proc_fs.h>
16 #include <linux/part_stat.h>
17
18 #include "ext4.h"
19 #include "ext4_jbd2.h"
20
21 typedef enum {
22 attr_noop,
23 attr_delayed_allocation_blocks,
24 attr_session_write_kbytes,
25 attr_lifetime_write_kbytes,
26 attr_reserved_clusters,
27 attr_sra_exceeded_retry_limit,
28 attr_inode_readahead,
29 attr_trigger_test_error,
30 attr_first_error_time,
31 attr_last_error_time,
32 attr_clusters_in_group,
33 attr_mb_order,
34 attr_feature,
35 attr_pointer_pi,
36 attr_pointer_ui,
37 attr_pointer_ul,
38 attr_pointer_u64,
39 attr_pointer_u8,
40 attr_pointer_string,
41 attr_pointer_atomic,
42 attr_journal_task,
43 } attr_id_t;
44
45 typedef enum {
46 ptr_explicit,
47 ptr_ext4_sb_info_offset,
48 ptr_ext4_super_block_offset,
49 } attr_ptr_t;
50
51 static const char proc_dirname[] = "fs/ext4";
52 static struct proc_dir_entry *ext4_proc_root;
53
54 struct ext4_attr {
55 struct attribute attr;
56 short attr_id;
57 short attr_ptr;
58 unsigned short attr_size;
59 union {
60 int offset;
61 void *explicit_ptr;
62 } u;
63 };
64
65 static ssize_t session_write_kbytes_show(struc
66 {
67 struct super_block *sb = sbi->s_buddy_
68
69 return sysfs_emit(buf, "%lu\n",
70 (part_stat_read(sb->s_
71 sbi->s_sectors_writte
72 }
73
74 static ssize_t lifetime_write_kbytes_show(stru
75 {
76 struct super_block *sb = sbi->s_buddy_
77
78 return sysfs_emit(buf, "%llu\n",
79 (unsigned long long)(s
80 ((part_stat_read(sb->s
81 EXT4_SB(sb)->s_secto
82 }
83
84 static ssize_t inode_readahead_blks_store(stru
85 cons
86 {
87 unsigned long t;
88 int ret;
89
90 ret = kstrtoul(skip_spaces(buf), 0, &t
91 if (ret)
92 return ret;
93
94 if (t && (!is_power_of_2(t) || t > 0x4
95 return -EINVAL;
96
97 sbi->s_inode_readahead_blks = t;
98 return count;
99 }
100
101 static ssize_t reserved_clusters_store(struct
102 const char
103 {
104 unsigned long long val;
105 ext4_fsblk_t clusters = (ext4_blocks_c
106 sbi->s_cluste
107 int ret;
108
109 ret = kstrtoull(skip_spaces(buf), 0, &
110 if (ret || val >= clusters || (s64)val
111 return -EINVAL;
112
113 atomic64_set(&sbi->s_resv_clusters, va
114 return count;
115 }
116
117 static ssize_t trigger_test_error(struct ext4_
118 const char *
119 {
120 int len = count;
121
122 if (!capable(CAP_SYS_ADMIN))
123 return -EPERM;
124
125 if (len && buf[len-1] == '\n')
126 len--;
127
128 if (len)
129 ext4_error(sbi->s_sb, "%.*s",
130 return count;
131 }
132
133 static ssize_t journal_task_show(struct ext4_s
134 {
135 if (!sbi->s_journal)
136 return sysfs_emit(buf, "<none>
137 return sysfs_emit(buf, "%d\n",
138 task_pid_vnr(sbi->s_jo
139 }
140
141 #define EXT4_ATTR(_name,_mode,_id)
142 static struct ext4_attr ext4_attr_##_name = {
143 .attr = {.name = __stringify(_name), .
144 .attr_id = attr_##_id,
145 }
146
147 #define EXT4_ATTR_FUNC(_name,_mode) EXT4_ATTR
148
149 #define EXT4_ATTR_FEATURE(_name) EXT4_ATTR(_
150
151 #define EXT4_ATTR_OFFSET(_name,_mode,_id,_stru
152 static struct ext4_attr ext4_attr_##_name = {
153 .attr = {.name = __stringify(_name), .
154 .attr_id = attr_##_id,
155 .attr_ptr = ptr_##_struct##_offset,
156 .u = {
157 .offset = offsetof(struct _str
158 },
159 }
160
161 #define EXT4_ATTR_STRING(_name,_mode,_size,_st
162 static struct ext4_attr ext4_attr_##_name = {
163 .attr = {.name = __stringify(_name), .
164 .attr_id = attr_pointer_string,
165 .attr_size = _size,
166 .attr_ptr = ptr_##_struct##_offset,
167 .u = {
168 .offset = offsetof(struct _str
169 },
170 }
171
172 #define EXT4_RO_ATTR_ES_UI(_name,_elname)
173 EXT4_ATTR_OFFSET(_name, 0444, pointer_
174
175 #define EXT4_RO_ATTR_ES_U8(_name,_elname)
176 EXT4_ATTR_OFFSET(_name, 0444, pointer_
177
178 #define EXT4_RO_ATTR_ES_U64(_name,_elname)
179 EXT4_ATTR_OFFSET(_name, 0444, pointer_
180
181 #define EXT4_RO_ATTR_ES_STRING(_name,_elname,_
182 EXT4_ATTR_STRING(_name, 0444, _size, e
183
184 #define EXT4_RW_ATTR_SBI_PI(_name,_elname)
185 EXT4_ATTR_OFFSET(_name, 0644, pointer_
186
187 #define EXT4_RW_ATTR_SBI_UI(_name,_elname)
188 EXT4_ATTR_OFFSET(_name, 0644, pointer_
189
190 #define EXT4_RW_ATTR_SBI_UL(_name,_elname)
191 EXT4_ATTR_OFFSET(_name, 0644, pointer_
192
193 #define EXT4_RO_ATTR_SBI_ATOMIC(_name,_elname)
194 EXT4_ATTR_OFFSET(_name, 0444, pointer_
195
196 #define EXT4_ATTR_PTR(_name,_mode,_id,_ptr) \
197 static struct ext4_attr ext4_attr_##_name = {
198 .attr = {.name = __stringify(_name), .
199 .attr_id = attr_##_id,
200 .attr_ptr = ptr_explicit,
201 .u = {
202 .explicit_ptr = _ptr,
203 },
204 }
205
206 #define ATTR_LIST(name) &ext4_attr_##name.attr
207
208 EXT4_ATTR_FUNC(delayed_allocation_blocks, 0444
209 EXT4_ATTR_FUNC(session_write_kbytes, 0444);
210 EXT4_ATTR_FUNC(lifetime_write_kbytes, 0444);
211 EXT4_ATTR_FUNC(reserved_clusters, 0644);
212 EXT4_ATTR_FUNC(sra_exceeded_retry_limit, 0444)
213
214 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, i
215 ext4_sb_info, s_inode_readahe
216 EXT4_ATTR_OFFSET(mb_group_prealloc, 0644, clus
217 ext4_sb_info, s_mb_group_prea
218 EXT4_ATTR_OFFSET(mb_best_avail_max_trim_order,
219 ext4_sb_info, s_mb_best_avail
220 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
221 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
222 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_t
223 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_t
224 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2
225 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream
226 EXT4_RW_ATTR_SBI_UI(mb_max_linear_groups, s_mb
227 EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_e
228 EXT4_ATTR(trigger_fs_error, 0200, trigger_test
229 EXT4_RW_ATTR_SBI_PI(err_ratelimit_interval_ms,
230 EXT4_RW_ATTR_SBI_PI(err_ratelimit_burst, s_err
231 EXT4_RW_ATTR_SBI_PI(warning_ratelimit_interval
232 EXT4_RW_ATTR_SBI_PI(warning_ratelimit_burst, s
233 EXT4_RW_ATTR_SBI_PI(msg_ratelimit_interval_ms,
234 EXT4_RW_ATTR_SBI_PI(msg_ratelimit_burst, s_msg
235 #ifdef CONFIG_EXT4_DEBUG
236 EXT4_RW_ATTR_SBI_UL(simulate_fail, s_simulate_
237 #endif
238 EXT4_RO_ATTR_SBI_ATOMIC(warning_count, s_warni
239 EXT4_RO_ATTR_SBI_ATOMIC(msg_count, s_msg_count
240 EXT4_RO_ATTR_ES_UI(errors_count, s_error_count
241 EXT4_RO_ATTR_ES_U8(first_error_errcode, s_firs
242 EXT4_RO_ATTR_ES_U8(last_error_errcode, s_last_
243 EXT4_RO_ATTR_ES_UI(first_error_ino, s_first_er
244 EXT4_RO_ATTR_ES_UI(last_error_ino, s_last_erro
245 EXT4_RO_ATTR_ES_U64(first_error_block, s_first
246 EXT4_RO_ATTR_ES_U64(last_error_block, s_last_e
247 EXT4_RO_ATTR_ES_UI(first_error_line, s_first_e
248 EXT4_RO_ATTR_ES_UI(last_error_line, s_last_err
249 EXT4_RO_ATTR_ES_STRING(first_error_func, s_fir
250 EXT4_RO_ATTR_ES_STRING(last_error_func, s_last
251 EXT4_ATTR(first_error_time, 0444, first_error_
252 EXT4_ATTR(last_error_time, 0444, last_error_ti
253 EXT4_ATTR(journal_task, 0444, journal_task);
254 EXT4_RW_ATTR_SBI_UI(mb_prefetch, s_mb_prefetch
255 EXT4_RW_ATTR_SBI_UI(mb_prefetch_limit, s_mb_pr
256 EXT4_RW_ATTR_SBI_UL(last_trim_minblks, s_last_
257
258 static unsigned int old_bump_val = 128;
259 EXT4_ATTR_PTR(max_writeback_mb_bump, 0444, poi
260
261 static struct attribute *ext4_attrs[] = {
262 ATTR_LIST(delayed_allocation_blocks),
263 ATTR_LIST(session_write_kbytes),
264 ATTR_LIST(lifetime_write_kbytes),
265 ATTR_LIST(reserved_clusters),
266 ATTR_LIST(sra_exceeded_retry_limit),
267 ATTR_LIST(inode_readahead_blks),
268 ATTR_LIST(inode_goal),
269 ATTR_LIST(mb_stats),
270 ATTR_LIST(mb_max_to_scan),
271 ATTR_LIST(mb_min_to_scan),
272 ATTR_LIST(mb_order2_req),
273 ATTR_LIST(mb_stream_req),
274 ATTR_LIST(mb_group_prealloc),
275 ATTR_LIST(mb_max_linear_groups),
276 ATTR_LIST(max_writeback_mb_bump),
277 ATTR_LIST(extent_max_zeroout_kb),
278 ATTR_LIST(trigger_fs_error),
279 ATTR_LIST(err_ratelimit_interval_ms),
280 ATTR_LIST(err_ratelimit_burst),
281 ATTR_LIST(warning_ratelimit_interval_m
282 ATTR_LIST(warning_ratelimit_burst),
283 ATTR_LIST(msg_ratelimit_interval_ms),
284 ATTR_LIST(msg_ratelimit_burst),
285 ATTR_LIST(mb_best_avail_max_trim_order
286 ATTR_LIST(errors_count),
287 ATTR_LIST(warning_count),
288 ATTR_LIST(msg_count),
289 ATTR_LIST(first_error_ino),
290 ATTR_LIST(last_error_ino),
291 ATTR_LIST(first_error_block),
292 ATTR_LIST(last_error_block),
293 ATTR_LIST(first_error_line),
294 ATTR_LIST(last_error_line),
295 ATTR_LIST(first_error_func),
296 ATTR_LIST(last_error_func),
297 ATTR_LIST(first_error_errcode),
298 ATTR_LIST(last_error_errcode),
299 ATTR_LIST(first_error_time),
300 ATTR_LIST(last_error_time),
301 ATTR_LIST(journal_task),
302 #ifdef CONFIG_EXT4_DEBUG
303 ATTR_LIST(simulate_fail),
304 #endif
305 ATTR_LIST(mb_prefetch),
306 ATTR_LIST(mb_prefetch_limit),
307 ATTR_LIST(last_trim_minblks),
308 NULL,
309 };
310 ATTRIBUTE_GROUPS(ext4);
311
312 /* Features this copy of ext4 supports */
313 EXT4_ATTR_FEATURE(lazy_itable_init);
314 EXT4_ATTR_FEATURE(batched_discard);
315 EXT4_ATTR_FEATURE(meta_bg_resize);
316 #ifdef CONFIG_FS_ENCRYPTION
317 EXT4_ATTR_FEATURE(encryption);
318 EXT4_ATTR_FEATURE(test_dummy_encryption_v2);
319 #endif
320 #if IS_ENABLED(CONFIG_UNICODE)
321 EXT4_ATTR_FEATURE(casefold);
322 #endif
323 #ifdef CONFIG_FS_VERITY
324 EXT4_ATTR_FEATURE(verity);
325 #endif
326 EXT4_ATTR_FEATURE(metadata_csum_seed);
327 EXT4_ATTR_FEATURE(fast_commit);
328 #if IS_ENABLED(CONFIG_UNICODE) && defined(CONF
329 EXT4_ATTR_FEATURE(encrypted_casefold);
330 #endif
331
332 static struct attribute *ext4_feat_attrs[] = {
333 ATTR_LIST(lazy_itable_init),
334 ATTR_LIST(batched_discard),
335 ATTR_LIST(meta_bg_resize),
336 #ifdef CONFIG_FS_ENCRYPTION
337 ATTR_LIST(encryption),
338 ATTR_LIST(test_dummy_encryption_v2),
339 #endif
340 #if IS_ENABLED(CONFIG_UNICODE)
341 ATTR_LIST(casefold),
342 #endif
343 #ifdef CONFIG_FS_VERITY
344 ATTR_LIST(verity),
345 #endif
346 ATTR_LIST(metadata_csum_seed),
347 ATTR_LIST(fast_commit),
348 #if IS_ENABLED(CONFIG_UNICODE) && defined(CONF
349 ATTR_LIST(encrypted_casefold),
350 #endif
351 NULL,
352 };
353 ATTRIBUTE_GROUPS(ext4_feat);
354
355 static void *calc_ptr(struct ext4_attr *a, str
356 {
357 switch (a->attr_ptr) {
358 case ptr_explicit:
359 return a->u.explicit_ptr;
360 case ptr_ext4_sb_info_offset:
361 return (void *) (((char *) sbi
362 case ptr_ext4_super_block_offset:
363 return (void *) (((char *) sbi
364 }
365 return NULL;
366 }
367
368 static ssize_t __print_tstamp(char *buf, __le3
369 {
370 return sysfs_emit(buf, "%lld\n",
371 ((time64_t)hi << 32) +
372 }
373
374 #define print_tstamp(buf, es, tstamp) \
375 __print_tstamp(buf, (es)->tstamp, (es)
376
377 static ssize_t ext4_generic_attr_show(struct e
378 struct e
379 {
380 void *ptr = calc_ptr(a, sbi);
381
382 if (!ptr)
383 return 0;
384
385 switch (a->attr_id) {
386 case attr_inode_readahead:
387 case attr_clusters_in_group:
388 case attr_mb_order:
389 case attr_pointer_pi:
390 case attr_pointer_ui:
391 if (a->attr_ptr == ptr_ext4_su
392 return sysfs_emit(buf,
393 return sysfs_emit(buf, "%u\n",
394 case attr_pointer_ul:
395 return sysfs_emit(buf, "%lu\n"
396 case attr_pointer_u8:
397 return sysfs_emit(buf, "%u\n",
398 case attr_pointer_u64:
399 if (a->attr_ptr == ptr_ext4_su
400 return sysfs_emit(buf,
401 return sysfs_emit(buf, "%llu\n
402 case attr_pointer_string:
403 return sysfs_emit(buf, "%.*s\n
404 case attr_pointer_atomic:
405 return sysfs_emit(buf, "%d\n",
406 }
407 return 0;
408 }
409
410 static ssize_t ext4_attr_show(struct kobject *
411 struct attribute
412 {
413 struct ext4_sb_info *sbi = container_o
414
415 struct ext4_attr *a = container_of(att
416
417 switch (a->attr_id) {
418 case attr_delayed_allocation_blocks:
419 return sysfs_emit(buf, "%llu\n
420 (s64) EXT4_C2B
421 percpu_counter_sum(&sbi
422 case attr_session_write_kbytes:
423 return session_write_kbytes_sh
424 case attr_lifetime_write_kbytes:
425 return lifetime_write_kbytes_s
426 case attr_reserved_clusters:
427 return sysfs_emit(buf, "%llu\n
428 (unsigned long
429 atomic64_read(
430 case attr_sra_exceeded_retry_limit:
431 return sysfs_emit(buf, "%llu\n
432 (unsigned long
433 percpu_counter_sum(&sb
434 case attr_feature:
435 return sysfs_emit(buf, "suppor
436 case attr_first_error_time:
437 return print_tstamp(buf, sbi->
438 case attr_last_error_time:
439 return print_tstamp(buf, sbi->
440 case attr_journal_task:
441 return journal_task_show(sbi,
442 default:
443 return ext4_generic_attr_show(
444 }
445 }
446
447 static ssize_t ext4_generic_attr_store(struct
448 struct
449 const c
450 {
451 int ret;
452 unsigned int t;
453 unsigned long lt;
454 void *ptr = calc_ptr(a, sbi);
455
456 if (!ptr)
457 return 0;
458
459 switch (a->attr_id) {
460 case attr_pointer_pi:
461 ret = kstrtouint(skip_spaces(b
462 if (ret)
463 return ret;
464 if ((int)t < 0)
465 return -EINVAL;
466 *((unsigned int *) ptr) = t;
467 return len;
468 case attr_pointer_ui:
469 ret = kstrtouint(skip_spaces(b
470 if (ret)
471 return ret;
472 if (a->attr_ptr == ptr_ext4_su
473 *((__le32 *) ptr) = cp
474 else
475 *((unsigned int *) ptr
476 return len;
477 case attr_mb_order:
478 ret = kstrtouint(skip_spaces(b
479 if (ret)
480 return ret;
481 if (t > 64)
482 return -EINVAL;
483 *((unsigned int *) ptr) = t;
484 return len;
485 case attr_clusters_in_group:
486 ret = kstrtouint(skip_spaces(b
487 if (ret)
488 return ret;
489 if (t > sbi->s_clusters_per_gr
490 return -EINVAL;
491 *((unsigned int *) ptr) = t;
492 return len;
493 case attr_pointer_ul:
494 ret = kstrtoul(skip_spaces(buf
495 if (ret)
496 return ret;
497 *((unsigned long *) ptr) = lt;
498 return len;
499 }
500 return 0;
501 }
502
503 static ssize_t ext4_attr_store(struct kobject
504 struct attribut
505 const char *buf
506 {
507 struct ext4_sb_info *sbi = container_o
508
509 struct ext4_attr *a = container_of(att
510
511 switch (a->attr_id) {
512 case attr_reserved_clusters:
513 return reserved_clusters_store
514 case attr_inode_readahead:
515 return inode_readahead_blks_st
516 case attr_trigger_test_error:
517 return trigger_test_error(sbi,
518 default:
519 return ext4_generic_attr_store
520 }
521 }
522
523 static void ext4_sb_release(struct kobject *ko
524 {
525 struct ext4_sb_info *sbi = container_o
526
527 complete(&sbi->s_kobj_unregister);
528 }
529
530 static void ext4_feat_release(struct kobject *
531 {
532 kfree(kobj);
533 }
534
535 static const struct sysfs_ops ext4_attr_ops =
536 .show = ext4_attr_show,
537 .store = ext4_attr_store,
538 };
539
540 static const struct kobj_type ext4_sb_ktype =
541 .default_groups = ext4_groups,
542 .sysfs_ops = &ext4_attr_ops,
543 .release = ext4_sb_release,
544 };
545
546 static const struct kobj_type ext4_feat_ktype
547 .default_groups = ext4_feat_groups,
548 .sysfs_ops = &ext4_attr_ops,
549 .release = ext4_feat_release,
550 };
551
552 void ext4_notify_error_sysfs(struct ext4_sb_in
553 {
554 sysfs_notify(&sbi->s_kobj, NULL, "erro
555 }
556
557 static struct kobject *ext4_root;
558
559 static struct kobject *ext4_feat;
560
561 int ext4_register_sysfs(struct super_block *sb
562 {
563 struct ext4_sb_info *sbi = EXT4_SB(sb)
564 int err;
565
566 init_completion(&sbi->s_kobj_unregiste
567 err = kobject_init_and_add(&sbi->s_kob
568 "%s", sb->s
569 if (err) {
570 kobject_put(&sbi->s_kobj);
571 wait_for_completion(&sbi->s_ko
572 return err;
573 }
574
575 if (ext4_proc_root)
576 sbi->s_proc = proc_mkdir(sb->s
577 if (sbi->s_proc) {
578 proc_create_single_data("optio
579 ext4_seq_optio
580 proc_create_single_data("es_sh
581 sbi->s_proc, e
582 sb);
583 proc_create_single_data("fc_in
584 ext4_f
585 proc_create_seq_data("mb_group
586 &ext4_mb_seq_g
587 proc_create_single_data("mb_st
588 ext4_seq_mb_st
589 proc_create_seq_data("mb_struc
590 &ext4_mb_seq_s
591 }
592 return 0;
593 }
594
595 void ext4_unregister_sysfs(struct super_block
596 {
597 struct ext4_sb_info *sbi = EXT4_SB(sb)
598
599 if (sbi->s_proc)
600 remove_proc_subtree(sb->s_id,
601 kobject_del(&sbi->s_kobj);
602 }
603
604 int __init ext4_init_sysfs(void)
605 {
606 int ret;
607
608 ext4_root = kobject_create_and_add("ex
609 if (!ext4_root)
610 return -ENOMEM;
611
612 ext4_feat = kzalloc(sizeof(*ext4_feat)
613 if (!ext4_feat) {
614 ret = -ENOMEM;
615 goto root_err;
616 }
617
618 ret = kobject_init_and_add(ext4_feat,
619 ext4_root,
620 if (ret)
621 goto feat_err;
622
623 ext4_proc_root = proc_mkdir(proc_dirna
624 return ret;
625
626 feat_err:
627 kobject_put(ext4_feat);
628 ext4_feat = NULL;
629 root_err:
630 kobject_put(ext4_root);
631 ext4_root = NULL;
632 return ret;
633 }
634
635 void ext4_exit_sysfs(void)
636 {
637 kobject_put(ext4_feat);
638 ext4_feat = NULL;
639 kobject_put(ext4_root);
640 ext4_root = NULL;
641 remove_proc_entry(proc_dirname, NULL);
642 ext4_proc_root = NULL;
643 }
644
645
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