1 // SPDX-License-Identifier: GPL-2.0
3 * linux/fs/ext4/sysfs.c
5 * Copyright (C) 1992, 1993, 1994, 1995
6 * Remy Card (card@masi.ibp.fr)
7 * Theodore Ts'o (tytso@mit.edu)
11 #include <linux/time.h>
13 #include <linux/seq_file.h>
14 #include <linux/slab.h>
15 #include <linux/proc_fs.h>
16 #include <linux/part_stat.h>
19 #include "ext4_jbd2.h"
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,
29 attr_trigger_test_error,
30 attr_first_error_time,
44 ptr_ext4_sb_info_offset,
45 ptr_ext4_super_block_offset,
48 static const char proc_dirname[] = "fs/ext4";
49 static struct proc_dir_entry *ext4_proc_root;
52 struct attribute attr;
55 unsigned short attr_size;
62 static ssize_t session_write_kbytes_show(struct ext4_sb_info *sbi, char *buf)
64 struct super_block *sb = sbi->s_buddy_cache->i_sb;
66 if (!sb->s_bdev->bd_part)
67 return snprintf(buf, PAGE_SIZE, "0\n");
68 return snprintf(buf, PAGE_SIZE, "%lu\n",
69 (part_stat_read(sb->s_bdev->bd_part,
70 sectors[STAT_WRITE]) -
71 sbi->s_sectors_written_start) >> 1);
74 static ssize_t lifetime_write_kbytes_show(struct ext4_sb_info *sbi, char *buf)
76 struct super_block *sb = sbi->s_buddy_cache->i_sb;
78 if (!sb->s_bdev->bd_part)
79 return snprintf(buf, PAGE_SIZE, "0\n");
80 return snprintf(buf, PAGE_SIZE, "%llu\n",
81 (unsigned long long)(sbi->s_kbytes_written +
82 ((part_stat_read(sb->s_bdev->bd_part,
83 sectors[STAT_WRITE]) -
84 EXT4_SB(sb)->s_sectors_written_start) >> 1)));
87 static ssize_t inode_readahead_blks_store(struct ext4_sb_info *sbi,
88 const char *buf, size_t count)
93 ret = kstrtoul(skip_spaces(buf), 0, &t);
97 if (t && (!is_power_of_2(t) || t > 0x40000000))
100 sbi->s_inode_readahead_blks = t;
104 static ssize_t reserved_clusters_store(struct ext4_sb_info *sbi,
105 const char *buf, size_t count)
107 unsigned long long val;
108 ext4_fsblk_t clusters = (ext4_blocks_count(sbi->s_es) >>
109 sbi->s_cluster_bits);
112 ret = kstrtoull(skip_spaces(buf), 0, &val);
113 if (ret || val >= clusters)
116 atomic64_set(&sbi->s_resv_clusters, val);
120 static ssize_t trigger_test_error(struct ext4_sb_info *sbi,
121 const char *buf, size_t count)
125 if (!capable(CAP_SYS_ADMIN))
128 if (len && buf[len-1] == '\n')
132 ext4_error(sbi->s_sb, "%.*s", len, buf);
136 static ssize_t journal_task_show(struct ext4_sb_info *sbi, char *buf)
139 return snprintf(buf, PAGE_SIZE, "<none>\n");
140 return snprintf(buf, PAGE_SIZE, "%d\n",
141 task_pid_vnr(sbi->s_journal->j_task));
144 #define EXT4_ATTR(_name,_mode,_id) \
145 static struct ext4_attr ext4_attr_##_name = { \
146 .attr = {.name = __stringify(_name), .mode = _mode }, \
147 .attr_id = attr_##_id, \
150 #define EXT4_ATTR_FUNC(_name,_mode) EXT4_ATTR(_name,_mode,_name)
152 #define EXT4_ATTR_FEATURE(_name) EXT4_ATTR(_name, 0444, feature)
154 #define EXT4_ATTR_OFFSET(_name,_mode,_id,_struct,_elname) \
155 static struct ext4_attr ext4_attr_##_name = { \
156 .attr = {.name = __stringify(_name), .mode = _mode }, \
157 .attr_id = attr_##_id, \
158 .attr_ptr = ptr_##_struct##_offset, \
160 .offset = offsetof(struct _struct, _elname),\
164 #define EXT4_ATTR_STRING(_name,_mode,_size,_struct,_elname) \
165 static struct ext4_attr ext4_attr_##_name = { \
166 .attr = {.name = __stringify(_name), .mode = _mode }, \
167 .attr_id = attr_pointer_string, \
168 .attr_size = _size, \
169 .attr_ptr = ptr_##_struct##_offset, \
171 .offset = offsetof(struct _struct, _elname),\
175 #define EXT4_RO_ATTR_ES_UI(_name,_elname) \
176 EXT4_ATTR_OFFSET(_name, 0444, pointer_ui, ext4_super_block, _elname)
178 #define EXT4_RO_ATTR_ES_U8(_name,_elname) \
179 EXT4_ATTR_OFFSET(_name, 0444, pointer_u8, ext4_super_block, _elname)
181 #define EXT4_RO_ATTR_ES_U64(_name,_elname) \
182 EXT4_ATTR_OFFSET(_name, 0444, pointer_u64, ext4_super_block, _elname)
184 #define EXT4_RO_ATTR_ES_STRING(_name,_elname,_size) \
185 EXT4_ATTR_STRING(_name, 0444, _size, ext4_super_block, _elname)
187 #define EXT4_RW_ATTR_SBI_UI(_name,_elname) \
188 EXT4_ATTR_OFFSET(_name, 0644, pointer_ui, ext4_sb_info, _elname)
190 #define EXT4_RW_ATTR_SBI_UL(_name,_elname) \
191 EXT4_ATTR_OFFSET(_name, 0644, pointer_ul, ext4_sb_info, _elname)
193 #define EXT4_RO_ATTR_SBI_ATOMIC(_name,_elname) \
194 EXT4_ATTR_OFFSET(_name, 0444, pointer_atomic, ext4_sb_info, _elname)
196 #define EXT4_ATTR_PTR(_name,_mode,_id,_ptr) \
197 static struct ext4_attr ext4_attr_##_name = { \
198 .attr = {.name = __stringify(_name), .mode = _mode }, \
199 .attr_id = attr_##_id, \
200 .attr_ptr = ptr_explicit, \
202 .explicit_ptr = _ptr, \
206 #define ATTR_LIST(name) &ext4_attr_##name.attr
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);
214 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, inode_readahead,
215 ext4_sb_info, s_inode_readahead_blks);
216 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
217 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
218 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
219 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
220 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
221 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
222 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
223 EXT4_RW_ATTR_SBI_UI(mb_max_inode_prealloc, s_mb_max_inode_prealloc);
224 EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb);
225 EXT4_ATTR(trigger_fs_error, 0200, trigger_test_error);
226 EXT4_RW_ATTR_SBI_UI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval);
227 EXT4_RW_ATTR_SBI_UI(err_ratelimit_burst, s_err_ratelimit_state.burst);
228 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval);
229 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_burst, s_warning_ratelimit_state.burst);
230 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval);
231 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_burst, s_msg_ratelimit_state.burst);
232 #ifdef CONFIG_EXT4_DEBUG
233 EXT4_RW_ATTR_SBI_UL(simulate_fail, s_simulate_fail);
235 EXT4_RO_ATTR_SBI_ATOMIC(warning_count, s_warning_count);
236 EXT4_RO_ATTR_SBI_ATOMIC(msg_count, s_msg_count);
237 EXT4_RO_ATTR_ES_UI(errors_count, s_error_count);
238 EXT4_RO_ATTR_ES_U8(first_error_errcode, s_first_error_errcode);
239 EXT4_RO_ATTR_ES_U8(last_error_errcode, s_last_error_errcode);
240 EXT4_RO_ATTR_ES_UI(first_error_ino, s_first_error_ino);
241 EXT4_RO_ATTR_ES_UI(last_error_ino, s_last_error_ino);
242 EXT4_RO_ATTR_ES_U64(first_error_block, s_first_error_block);
243 EXT4_RO_ATTR_ES_U64(last_error_block, s_last_error_block);
244 EXT4_RO_ATTR_ES_UI(first_error_line, s_first_error_line);
245 EXT4_RO_ATTR_ES_UI(last_error_line, s_last_error_line);
246 EXT4_RO_ATTR_ES_STRING(first_error_func, s_first_error_func, 32);
247 EXT4_RO_ATTR_ES_STRING(last_error_func, s_last_error_func, 32);
248 EXT4_ATTR(first_error_time, 0444, first_error_time);
249 EXT4_ATTR(last_error_time, 0444, last_error_time);
250 EXT4_ATTR(journal_task, 0444, journal_task);
251 EXT4_RW_ATTR_SBI_UI(mb_prefetch, s_mb_prefetch);
252 EXT4_RW_ATTR_SBI_UI(mb_prefetch_limit, s_mb_prefetch_limit);
254 static unsigned int old_bump_val = 128;
255 EXT4_ATTR_PTR(max_writeback_mb_bump, 0444, pointer_ui, &old_bump_val);
257 static struct attribute *ext4_attrs[] = {
258 ATTR_LIST(delayed_allocation_blocks),
259 ATTR_LIST(session_write_kbytes),
260 ATTR_LIST(lifetime_write_kbytes),
261 ATTR_LIST(reserved_clusters),
262 ATTR_LIST(sra_exceeded_retry_limit),
263 ATTR_LIST(inode_readahead_blks),
264 ATTR_LIST(inode_goal),
266 ATTR_LIST(mb_max_to_scan),
267 ATTR_LIST(mb_min_to_scan),
268 ATTR_LIST(mb_order2_req),
269 ATTR_LIST(mb_stream_req),
270 ATTR_LIST(mb_group_prealloc),
271 ATTR_LIST(mb_max_inode_prealloc),
272 ATTR_LIST(max_writeback_mb_bump),
273 ATTR_LIST(extent_max_zeroout_kb),
274 ATTR_LIST(trigger_fs_error),
275 ATTR_LIST(err_ratelimit_interval_ms),
276 ATTR_LIST(err_ratelimit_burst),
277 ATTR_LIST(warning_ratelimit_interval_ms),
278 ATTR_LIST(warning_ratelimit_burst),
279 ATTR_LIST(msg_ratelimit_interval_ms),
280 ATTR_LIST(msg_ratelimit_burst),
281 ATTR_LIST(errors_count),
282 ATTR_LIST(warning_count),
283 ATTR_LIST(msg_count),
284 ATTR_LIST(first_error_ino),
285 ATTR_LIST(last_error_ino),
286 ATTR_LIST(first_error_block),
287 ATTR_LIST(last_error_block),
288 ATTR_LIST(first_error_line),
289 ATTR_LIST(last_error_line),
290 ATTR_LIST(first_error_func),
291 ATTR_LIST(last_error_func),
292 ATTR_LIST(first_error_errcode),
293 ATTR_LIST(last_error_errcode),
294 ATTR_LIST(first_error_time),
295 ATTR_LIST(last_error_time),
296 ATTR_LIST(journal_task),
297 #ifdef CONFIG_EXT4_DEBUG
298 ATTR_LIST(simulate_fail),
300 ATTR_LIST(mb_prefetch),
301 ATTR_LIST(mb_prefetch_limit),
304 ATTRIBUTE_GROUPS(ext4);
306 /* Features this copy of ext4 supports */
307 EXT4_ATTR_FEATURE(lazy_itable_init);
308 EXT4_ATTR_FEATURE(batched_discard);
309 EXT4_ATTR_FEATURE(meta_bg_resize);
310 #ifdef CONFIG_FS_ENCRYPTION
311 EXT4_ATTR_FEATURE(encryption);
312 EXT4_ATTR_FEATURE(test_dummy_encryption_v2);
314 #ifdef CONFIG_UNICODE
315 EXT4_ATTR_FEATURE(casefold);
317 #ifdef CONFIG_FS_VERITY
318 EXT4_ATTR_FEATURE(verity);
320 EXT4_ATTR_FEATURE(metadata_csum_seed);
321 EXT4_ATTR_FEATURE(fast_commit);
323 static struct attribute *ext4_feat_attrs[] = {
324 ATTR_LIST(lazy_itable_init),
325 ATTR_LIST(batched_discard),
326 ATTR_LIST(meta_bg_resize),
327 #ifdef CONFIG_FS_ENCRYPTION
328 ATTR_LIST(encryption),
329 ATTR_LIST(test_dummy_encryption_v2),
331 #ifdef CONFIG_UNICODE
334 #ifdef CONFIG_FS_VERITY
337 ATTR_LIST(metadata_csum_seed),
338 ATTR_LIST(fast_commit),
341 ATTRIBUTE_GROUPS(ext4_feat);
343 static void *calc_ptr(struct ext4_attr *a, struct ext4_sb_info *sbi)
345 switch (a->attr_ptr) {
347 return a->u.explicit_ptr;
348 case ptr_ext4_sb_info_offset:
349 return (void *) (((char *) sbi) + a->u.offset);
350 case ptr_ext4_super_block_offset:
351 return (void *) (((char *) sbi->s_es) + a->u.offset);
356 static ssize_t __print_tstamp(char *buf, __le32 lo, __u8 hi)
358 return snprintf(buf, PAGE_SIZE, "%lld\n",
359 ((time64_t)hi << 32) + le32_to_cpu(lo));
362 #define print_tstamp(buf, es, tstamp) \
363 __print_tstamp(buf, (es)->tstamp, (es)->tstamp ## _hi)
365 static ssize_t ext4_attr_show(struct kobject *kobj,
366 struct attribute *attr, char *buf)
368 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
370 struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
371 void *ptr = calc_ptr(a, sbi);
373 switch (a->attr_id) {
374 case attr_delayed_allocation_blocks:
375 return snprintf(buf, PAGE_SIZE, "%llu\n",
377 percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
378 case attr_session_write_kbytes:
379 return session_write_kbytes_show(sbi, buf);
380 case attr_lifetime_write_kbytes:
381 return lifetime_write_kbytes_show(sbi, buf);
382 case attr_reserved_clusters:
383 return snprintf(buf, PAGE_SIZE, "%llu\n",
385 atomic64_read(&sbi->s_resv_clusters));
386 case attr_sra_exceeded_retry_limit:
387 return snprintf(buf, PAGE_SIZE, "%llu\n",
389 percpu_counter_sum(&sbi->s_sra_exceeded_retry_limit));
390 case attr_inode_readahead:
391 case attr_pointer_ui:
394 if (a->attr_ptr == ptr_ext4_super_block_offset)
395 return snprintf(buf, PAGE_SIZE, "%u\n",
398 return snprintf(buf, PAGE_SIZE, "%u\n",
399 *((unsigned int *) ptr));
400 case attr_pointer_ul:
403 return snprintf(buf, PAGE_SIZE, "%lu\n",
404 *((unsigned long *) ptr));
405 case attr_pointer_u8:
408 return snprintf(buf, PAGE_SIZE, "%u\n",
409 *((unsigned char *) ptr));
410 case attr_pointer_u64:
413 if (a->attr_ptr == ptr_ext4_super_block_offset)
414 return snprintf(buf, PAGE_SIZE, "%llu\n",
417 return snprintf(buf, PAGE_SIZE, "%llu\n",
418 *((unsigned long long *) ptr));
419 case attr_pointer_string:
422 return snprintf(buf, PAGE_SIZE, "%.*s\n", a->attr_size,
424 case attr_pointer_atomic:
427 return snprintf(buf, PAGE_SIZE, "%d\n",
428 atomic_read((atomic_t *) ptr));
430 return snprintf(buf, PAGE_SIZE, "supported\n");
431 case attr_first_error_time:
432 return print_tstamp(buf, sbi->s_es, s_first_error_time);
433 case attr_last_error_time:
434 return print_tstamp(buf, sbi->s_es, s_last_error_time);
435 case attr_journal_task:
436 return journal_task_show(sbi, buf);
442 static ssize_t ext4_attr_store(struct kobject *kobj,
443 struct attribute *attr,
444 const char *buf, size_t len)
446 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
448 struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
449 void *ptr = calc_ptr(a, sbi);
453 switch (a->attr_id) {
454 case attr_reserved_clusters:
455 return reserved_clusters_store(sbi, buf, len);
456 case attr_pointer_ui:
459 ret = kstrtoul(skip_spaces(buf), 0, &t);
462 if (a->attr_ptr == ptr_ext4_super_block_offset)
463 *((__le32 *) ptr) = cpu_to_le32(t);
465 *((unsigned int *) ptr) = t;
467 case attr_pointer_ul:
470 ret = kstrtoul(skip_spaces(buf), 0, &t);
473 *((unsigned long *) ptr) = t;
475 case attr_inode_readahead:
476 return inode_readahead_blks_store(sbi, buf, len);
477 case attr_trigger_test_error:
478 return trigger_test_error(sbi, buf, len);
483 static void ext4_sb_release(struct kobject *kobj)
485 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
487 complete(&sbi->s_kobj_unregister);
490 static void ext4_feat_release(struct kobject *kobj)
495 static const struct sysfs_ops ext4_attr_ops = {
496 .show = ext4_attr_show,
497 .store = ext4_attr_store,
500 static struct kobj_type ext4_sb_ktype = {
501 .default_groups = ext4_groups,
502 .sysfs_ops = &ext4_attr_ops,
503 .release = ext4_sb_release,
506 static struct kobj_type ext4_feat_ktype = {
507 .default_groups = ext4_feat_groups,
508 .sysfs_ops = &ext4_attr_ops,
509 .release = ext4_feat_release,
512 static struct kobject *ext4_root;
514 static struct kobject *ext4_feat;
516 int ext4_register_sysfs(struct super_block *sb)
518 struct ext4_sb_info *sbi = EXT4_SB(sb);
521 init_completion(&sbi->s_kobj_unregister);
522 err = kobject_init_and_add(&sbi->s_kobj, &ext4_sb_ktype, ext4_root,
525 kobject_put(&sbi->s_kobj);
526 wait_for_completion(&sbi->s_kobj_unregister);
531 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
533 proc_create_single_data("options", S_IRUGO, sbi->s_proc,
534 ext4_seq_options_show, sb);
535 proc_create_single_data("es_shrinker_info", S_IRUGO,
536 sbi->s_proc, ext4_seq_es_shrinker_info_show,
538 proc_create_single_data("fc_info", 0444, sbi->s_proc,
539 ext4_fc_info_show, sb);
540 proc_create_seq_data("mb_groups", S_IRUGO, sbi->s_proc,
541 &ext4_mb_seq_groups_ops, sb);
542 proc_create_single_data("mb_stats", 0444, sbi->s_proc,
543 ext4_seq_mb_stats_show, sb);
548 void ext4_unregister_sysfs(struct super_block *sb)
550 struct ext4_sb_info *sbi = EXT4_SB(sb);
553 remove_proc_subtree(sb->s_id, ext4_proc_root);
554 kobject_del(&sbi->s_kobj);
557 int __init ext4_init_sysfs(void)
561 ext4_root = kobject_create_and_add("ext4", fs_kobj);
565 ext4_feat = kzalloc(sizeof(*ext4_feat), GFP_KERNEL);
571 ret = kobject_init_and_add(ext4_feat, &ext4_feat_ktype,
572 ext4_root, "features");
576 ext4_proc_root = proc_mkdir(proc_dirname, NULL);
580 kobject_put(ext4_feat);
583 kobject_put(ext4_root);
588 void ext4_exit_sysfs(void)
590 kobject_put(ext4_feat);
592 kobject_put(ext4_root);
594 remove_proc_entry(proc_dirname, NULL);
595 ext4_proc_root = NULL;