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ext4: add sysfs attr /sys/fs/ext4/<disk>/journal_task
[thirdparty/kernel/stable.git] / fs / ext4 / sysfs.c
CommitLineData
b2441318 1// SPDX-License-Identifier: GPL-2.0
b5799018
TT
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>
b99fee58 14#include <linux/slab.h>
b5799018
TT
15#include <linux/proc_fs.h>
16
17#include "ext4.h"
18#include "ext4_jbd2.h"
19
76d33bca
TT
20typedef enum {
21 attr_noop,
22 attr_delayed_allocation_blocks,
23 attr_session_write_kbytes,
24 attr_lifetime_write_kbytes,
25 attr_reserved_clusters,
26 attr_inode_readahead,
27 attr_trigger_test_error,
6a0678a7
AB
28 attr_first_error_time,
29 attr_last_error_time,
76d33bca
TT
30 attr_feature,
31 attr_pointer_ui,
32 attr_pointer_atomic,
bc1d69d6 33 attr_journal_task,
76d33bca
TT
34} attr_id_t;
35
36typedef enum {
37 ptr_explicit,
38 ptr_ext4_sb_info_offset,
39 ptr_ext4_super_block_offset,
40} attr_ptr_t;
41
d6006186 42static const char proc_dirname[] = "fs/ext4";
ebd173be
TT
43static struct proc_dir_entry *ext4_proc_root;
44
b5799018
TT
45struct ext4_attr {
46 struct attribute attr;
76d33bca
TT
47 short attr_id;
48 short attr_ptr;
b5799018
TT
49 union {
50 int offset;
76d33bca 51 void *explicit_ptr;
b5799018
TT
52 } u;
53};
54
6ca06829 55static ssize_t session_write_kbytes_show(struct ext4_sb_info *sbi, char *buf)
b5799018
TT
56{
57 struct super_block *sb = sbi->s_buddy_cache->i_sb;
58
59 if (!sb->s_bdev->bd_part)
60 return snprintf(buf, PAGE_SIZE, "0\n");
61 return snprintf(buf, PAGE_SIZE, "%lu\n",
dbae2c55
MC
62 (part_stat_read(sb->s_bdev->bd_part,
63 sectors[STAT_WRITE]) -
b5799018
TT
64 sbi->s_sectors_written_start) >> 1);
65}
66
6ca06829 67static ssize_t lifetime_write_kbytes_show(struct ext4_sb_info *sbi, char *buf)
b5799018
TT
68{
69 struct super_block *sb = sbi->s_buddy_cache->i_sb;
70
71 if (!sb->s_bdev->bd_part)
72 return snprintf(buf, PAGE_SIZE, "0\n");
73 return snprintf(buf, PAGE_SIZE, "%llu\n",
74 (unsigned long long)(sbi->s_kbytes_written +
dbae2c55
MC
75 ((part_stat_read(sb->s_bdev->bd_part,
76 sectors[STAT_WRITE]) -
b5799018
TT
77 EXT4_SB(sb)->s_sectors_written_start) >> 1)));
78}
79
6ca06829 80static ssize_t inode_readahead_blks_store(struct ext4_sb_info *sbi,
b5799018
TT
81 const char *buf, size_t count)
82{
83 unsigned long t;
84 int ret;
85
86 ret = kstrtoul(skip_spaces(buf), 0, &t);
87 if (ret)
88 return ret;
89
90 if (t && (!is_power_of_2(t) || t > 0x40000000))
91 return -EINVAL;
92
93 sbi->s_inode_readahead_blks = t;
94 return count;
95}
96
6ca06829 97static ssize_t reserved_clusters_store(struct ext4_sb_info *sbi,
b5799018
TT
98 const char *buf, size_t count)
99{
100 unsigned long long val;
101 ext4_fsblk_t clusters = (ext4_blocks_count(sbi->s_es) >>
102 sbi->s_cluster_bits);
76d33bca 103 int ret;
b5799018 104
76d33bca 105 ret = kstrtoull(skip_spaces(buf), 0, &val);
1ea1516f 106 if (ret || val >= clusters)
b5799018
TT
107 return -EINVAL;
108
109 atomic64_set(&sbi->s_resv_clusters, val);
110 return count;
111}
112
6ca06829 113static ssize_t trigger_test_error(struct ext4_sb_info *sbi,
b5799018
TT
114 const char *buf, size_t count)
115{
116 int len = count;
117
118 if (!capable(CAP_SYS_ADMIN))
119 return -EPERM;
120
121 if (len && buf[len-1] == '\n')
122 len--;
123
124 if (len)
125 ext4_error(sbi->s_sb, "%.*s", len, buf);
126 return count;
127}
128
bc1d69d6
KK
129static ssize_t journal_task_show(struct ext4_sb_info *sbi, char *buf)
130{
131 if (!sbi->s_journal)
132 return snprintf(buf, PAGE_SIZE, "<none>\n");
133 return snprintf(buf, PAGE_SIZE, "%d\n",
134 task_pid_vnr(sbi->s_journal->j_task));
135}
136
76d33bca
TT
137#define EXT4_ATTR(_name,_mode,_id) \
138static struct ext4_attr ext4_attr_##_name = { \
139 .attr = {.name = __stringify(_name), .mode = _mode }, \
140 .attr_id = attr_##_id, \
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TT
141}
142
76d33bca
TT
143#define EXT4_ATTR_FUNC(_name,_mode) EXT4_ATTR(_name,_mode,_name)
144
145#define EXT4_ATTR_FEATURE(_name) EXT4_ATTR(_name, 0444, feature)
146
147#define EXT4_ATTR_OFFSET(_name,_mode,_id,_struct,_elname) \
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TT
148static struct ext4_attr ext4_attr_##_name = { \
149 .attr = {.name = __stringify(_name), .mode = _mode }, \
76d33bca
TT
150 .attr_id = attr_##_id, \
151 .attr_ptr = ptr_##_struct##_offset, \
b5799018 152 .u = { \
76d33bca 153 .offset = offsetof(struct _struct, _elname),\
b5799018
TT
154 }, \
155}
156
76d33bca
TT
157#define EXT4_RO_ATTR_ES_UI(_name,_elname) \
158 EXT4_ATTR_OFFSET(_name, 0444, pointer_ui, ext4_super_block, _elname)
b5799018 159
76d33bca
TT
160#define EXT4_RW_ATTR_SBI_UI(_name,_elname) \
161 EXT4_ATTR_OFFSET(_name, 0644, pointer_ui, ext4_sb_info, _elname)
b5799018 162
76d33bca 163#define EXT4_ATTR_PTR(_name,_mode,_id,_ptr) \
b5799018 164static struct ext4_attr ext4_attr_##_name = { \
76d33bca
TT
165 .attr = {.name = __stringify(_name), .mode = _mode }, \
166 .attr_id = attr_##_id, \
167 .attr_ptr = ptr_explicit, \
b5799018 168 .u = { \
76d33bca 169 .explicit_ptr = _ptr, \
b5799018
TT
170 }, \
171}
172
76d33bca
TT
173#define ATTR_LIST(name) &ext4_attr_##name.attr
174
175EXT4_ATTR_FUNC(delayed_allocation_blocks, 0444);
176EXT4_ATTR_FUNC(session_write_kbytes, 0444);
177EXT4_ATTR_FUNC(lifetime_write_kbytes, 0444);
178EXT4_ATTR_FUNC(reserved_clusters, 0644);
179
180EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, inode_readahead,
181 ext4_sb_info, s_inode_readahead_blks);
b5799018
TT
182EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
183EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
184EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
185EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
186EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
187EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
188EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
b5799018 189EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb);
76d33bca 190EXT4_ATTR(trigger_fs_error, 0200, trigger_test_error);
b5799018
TT
191EXT4_RW_ATTR_SBI_UI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval);
192EXT4_RW_ATTR_SBI_UI(err_ratelimit_burst, s_err_ratelimit_state.burst);
193EXT4_RW_ATTR_SBI_UI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval);
194EXT4_RW_ATTR_SBI_UI(warning_ratelimit_burst, s_warning_ratelimit_state.burst);
195EXT4_RW_ATTR_SBI_UI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval);
196EXT4_RW_ATTR_SBI_UI(msg_ratelimit_burst, s_msg_ratelimit_state.burst);
197EXT4_RO_ATTR_ES_UI(errors_count, s_error_count);
6a0678a7
AB
198EXT4_ATTR(first_error_time, 0444, first_error_time);
199EXT4_ATTR(last_error_time, 0444, last_error_time);
bc1d69d6 200EXT4_ATTR(journal_task, 0444, journal_task);
b5799018 201
76d33bca
TT
202static unsigned int old_bump_val = 128;
203EXT4_ATTR_PTR(max_writeback_mb_bump, 0444, pointer_ui, &old_bump_val);
204
b5799018
TT
205static struct attribute *ext4_attrs[] = {
206 ATTR_LIST(delayed_allocation_blocks),
207 ATTR_LIST(session_write_kbytes),
208 ATTR_LIST(lifetime_write_kbytes),
209 ATTR_LIST(reserved_clusters),
210 ATTR_LIST(inode_readahead_blks),
211 ATTR_LIST(inode_goal),
212 ATTR_LIST(mb_stats),
213 ATTR_LIST(mb_max_to_scan),
214 ATTR_LIST(mb_min_to_scan),
215 ATTR_LIST(mb_order2_req),
216 ATTR_LIST(mb_stream_req),
217 ATTR_LIST(mb_group_prealloc),
218 ATTR_LIST(max_writeback_mb_bump),
219 ATTR_LIST(extent_max_zeroout_kb),
220 ATTR_LIST(trigger_fs_error),
221 ATTR_LIST(err_ratelimit_interval_ms),
222 ATTR_LIST(err_ratelimit_burst),
223 ATTR_LIST(warning_ratelimit_interval_ms),
224 ATTR_LIST(warning_ratelimit_burst),
225 ATTR_LIST(msg_ratelimit_interval_ms),
226 ATTR_LIST(msg_ratelimit_burst),
227 ATTR_LIST(errors_count),
228 ATTR_LIST(first_error_time),
229 ATTR_LIST(last_error_time),
bc1d69d6 230 ATTR_LIST(journal_task),
b5799018
TT
231 NULL,
232};
233
234/* Features this copy of ext4 supports */
76d33bca
TT
235EXT4_ATTR_FEATURE(lazy_itable_init);
236EXT4_ATTR_FEATURE(batched_discard);
237EXT4_ATTR_FEATURE(meta_bg_resize);
c4704a4f 238#ifdef CONFIG_EXT4_FS_ENCRYPTION
76d33bca 239EXT4_ATTR_FEATURE(encryption);
c4704a4f 240#endif
8c81bd8f 241EXT4_ATTR_FEATURE(metadata_csum_seed);
b5799018
TT
242
243static struct attribute *ext4_feat_attrs[] = {
244 ATTR_LIST(lazy_itable_init),
245 ATTR_LIST(batched_discard),
246 ATTR_LIST(meta_bg_resize),
c4704a4f 247#ifdef CONFIG_EXT4_FS_ENCRYPTION
b5799018 248 ATTR_LIST(encryption),
c4704a4f 249#endif
8c81bd8f 250 ATTR_LIST(metadata_csum_seed),
b5799018
TT
251 NULL,
252};
253
76d33bca
TT
254static void *calc_ptr(struct ext4_attr *a, struct ext4_sb_info *sbi)
255{
256 switch (a->attr_ptr) {
257 case ptr_explicit:
258 return a->u.explicit_ptr;
259 case ptr_ext4_sb_info_offset:
260 return (void *) (((char *) sbi) + a->u.offset);
261 case ptr_ext4_super_block_offset:
262 return (void *) (((char *) sbi->s_es) + a->u.offset);
263 }
264 return NULL;
265}
266
6a0678a7
AB
267static ssize_t __print_tstamp(char *buf, __le32 lo, __u8 hi)
268{
269 return snprintf(buf, PAGE_SIZE, "%lld",
270 ((time64_t)hi << 32) + le32_to_cpu(lo));
271}
272
273#define print_tstamp(buf, es, tstamp) \
274 __print_tstamp(buf, (es)->tstamp, (es)->tstamp ## _hi)
275
b5799018
TT
276static ssize_t ext4_attr_show(struct kobject *kobj,
277 struct attribute *attr, char *buf)
278{
279 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
280 s_kobj);
281 struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
76d33bca
TT
282 void *ptr = calc_ptr(a, sbi);
283
284 switch (a->attr_id) {
285 case attr_delayed_allocation_blocks:
286 return snprintf(buf, PAGE_SIZE, "%llu\n",
287 (s64) EXT4_C2B(sbi,
288 percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
289 case attr_session_write_kbytes:
6ca06829 290 return session_write_kbytes_show(sbi, buf);
76d33bca 291 case attr_lifetime_write_kbytes:
6ca06829 292 return lifetime_write_kbytes_show(sbi, buf);
76d33bca
TT
293 case attr_reserved_clusters:
294 return snprintf(buf, PAGE_SIZE, "%llu\n",
295 (unsigned long long)
296 atomic64_read(&sbi->s_resv_clusters));
297 case attr_inode_readahead:
298 case attr_pointer_ui:
299 if (!ptr)
300 return 0;
a4d2aadc
AB
301 if (a->attr_ptr == ptr_ext4_super_block_offset)
302 return snprintf(buf, PAGE_SIZE, "%u\n",
303 le32_to_cpup(ptr));
304 else
305 return snprintf(buf, PAGE_SIZE, "%u\n",
306 *((unsigned int *) ptr));
76d33bca
TT
307 case attr_pointer_atomic:
308 if (!ptr)
309 return 0;
310 return snprintf(buf, PAGE_SIZE, "%d\n",
311 atomic_read((atomic_t *) ptr));
312 case attr_feature:
313 return snprintf(buf, PAGE_SIZE, "supported\n");
6a0678a7
AB
314 case attr_first_error_time:
315 return print_tstamp(buf, sbi->s_es, s_first_error_time);
316 case attr_last_error_time:
317 return print_tstamp(buf, sbi->s_es, s_last_error_time);
bc1d69d6
KK
318 case attr_journal_task:
319 return journal_task_show(sbi, buf);
76d33bca
TT
320 }
321
322 return 0;
b5799018
TT
323}
324
325static ssize_t ext4_attr_store(struct kobject *kobj,
326 struct attribute *attr,
327 const char *buf, size_t len)
328{
329 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
330 s_kobj);
331 struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
76d33bca
TT
332 void *ptr = calc_ptr(a, sbi);
333 unsigned long t;
334 int ret;
b5799018 335
76d33bca
TT
336 switch (a->attr_id) {
337 case attr_reserved_clusters:
6ca06829 338 return reserved_clusters_store(sbi, buf, len);
76d33bca
TT
339 case attr_pointer_ui:
340 if (!ptr)
341 return 0;
342 ret = kstrtoul(skip_spaces(buf), 0, &t);
343 if (ret)
344 return ret;
a4d2aadc
AB
345 if (a->attr_ptr == ptr_ext4_super_block_offset)
346 *((__le32 *) ptr) = cpu_to_le32(t);
347 else
348 *((unsigned int *) ptr) = t;
76d33bca
TT
349 return len;
350 case attr_inode_readahead:
6ca06829 351 return inode_readahead_blks_store(sbi, buf, len);
76d33bca 352 case attr_trigger_test_error:
6ca06829 353 return trigger_test_error(sbi, buf, len);
76d33bca
TT
354 }
355 return 0;
b5799018
TT
356}
357
358static void ext4_sb_release(struct kobject *kobj)
359{
360 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
361 s_kobj);
362 complete(&sbi->s_kobj_unregister);
363}
364
365static const struct sysfs_ops ext4_attr_ops = {
366 .show = ext4_attr_show,
367 .store = ext4_attr_store,
368};
369
370static struct kobj_type ext4_sb_ktype = {
371 .default_attrs = ext4_attrs,
372 .sysfs_ops = &ext4_attr_ops,
373 .release = ext4_sb_release,
374};
375
b5799018
TT
376static struct kobj_type ext4_feat_ktype = {
377 .default_attrs = ext4_feat_attrs,
76d33bca 378 .sysfs_ops = &ext4_attr_ops,
b99fee58 379 .release = (void (*)(struct kobject *))kfree,
b5799018
TT
380};
381
bc1420ae
TN
382static struct kobject *ext4_root;
383
b99fee58 384static struct kobject *ext4_feat;
b5799018
TT
385
386int ext4_register_sysfs(struct super_block *sb)
387{
388 struct ext4_sb_info *sbi = EXT4_SB(sb);
ebd173be 389 int err;
b5799018 390
b5799018 391 init_completion(&sbi->s_kobj_unregister);
bc1420ae 392 err = kobject_init_and_add(&sbi->s_kobj, &ext4_sb_ktype, ext4_root,
ebd173be 393 "%s", sb->s_id);
95c4df02
RS
394 if (err) {
395 kobject_put(&sbi->s_kobj);
396 wait_for_completion(&sbi->s_kobj_unregister);
ebd173be 397 return err;
95c4df02 398 }
ebd173be
TT
399
400 if (ext4_proc_root)
401 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
ebd173be 402 if (sbi->s_proc) {
247dbed8
CH
403 proc_create_single_data("options", S_IRUGO, sbi->s_proc,
404 ext4_seq_options_show, sb);
405 proc_create_single_data("es_shrinker_info", S_IRUGO,
406 sbi->s_proc, ext4_seq_es_shrinker_info_show,
407 sb);
408 proc_create_seq_data("mb_groups", S_IRUGO, sbi->s_proc,
409 &ext4_mb_seq_groups_ops, sb);
ebd173be
TT
410 }
411 return 0;
412}
413
414void ext4_unregister_sysfs(struct super_block *sb)
415{
416 struct ext4_sb_info *sbi = EXT4_SB(sb);
ebd173be 417
247dbed8
CH
418 if (sbi->s_proc)
419 remove_proc_subtree(sb->s_id, ext4_proc_root);
ebd173be 420 kobject_del(&sbi->s_kobj);
b5799018
TT
421}
422
423int __init ext4_init_sysfs(void)
424{
425 int ret;
426
bc1420ae
TN
427 ext4_root = kobject_create_and_add("ext4", fs_kobj);
428 if (!ext4_root)
5dc39711
RS
429 return -ENOMEM;
430
b99fee58
RS
431 ext4_feat = kzalloc(sizeof(*ext4_feat), GFP_KERNEL);
432 if (!ext4_feat) {
433 ret = -ENOMEM;
bc1420ae 434 goto root_err;
95c4df02 435 }
b99fee58 436
b99fee58 437 ret = kobject_init_and_add(ext4_feat, &ext4_feat_ktype,
bc1420ae 438 ext4_root, "features");
b99fee58
RS
439 if (ret)
440 goto feat_err;
441
442 ext4_proc_root = proc_mkdir(proc_dirname, NULL);
443 return ret;
444
445feat_err:
446 kobject_put(ext4_feat);
c2e5df76 447 ext4_feat = NULL;
bc1420ae
TN
448root_err:
449 kobject_put(ext4_root);
450 ext4_root = NULL;
b5799018
TT
451 return ret;
452}
453
454void ext4_exit_sysfs(void)
455{
b99fee58 456 kobject_put(ext4_feat);
c2e5df76 457 ext4_feat = NULL;
bc1420ae
TN
458 kobject_put(ext4_root);
459 ext4_root = NULL;
ebd173be
TT
460 remove_proc_entry(proc_dirname, NULL);
461 ext4_proc_root = NULL;
b5799018
TT
462}
463