645 lines · c
1// SPDX-License-Identifier: GPL-2.02/*3 * linux/fs/ext4/sysfs.c4 *5 * Copyright (C) 1992, 1993, 1994, 19956 * 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 21typedef 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 45typedef enum {46 ptr_explicit,47 ptr_ext4_sb_info_offset,48 ptr_ext4_super_block_offset,49} attr_ptr_t;50 51static const char proc_dirname[] = "fs/ext4";52static struct proc_dir_entry *ext4_proc_root;53 54struct 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 65static ssize_t session_write_kbytes_show(struct ext4_sb_info *sbi, char *buf)66{67 struct super_block *sb = sbi->s_buddy_cache->i_sb;68 69 return sysfs_emit(buf, "%lu\n",70 (part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -71 sbi->s_sectors_written_start) >> 1);72}73 74static ssize_t lifetime_write_kbytes_show(struct ext4_sb_info *sbi, char *buf)75{76 struct super_block *sb = sbi->s_buddy_cache->i_sb;77 78 return sysfs_emit(buf, "%llu\n",79 (unsigned long long)(sbi->s_kbytes_written +80 ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -81 EXT4_SB(sb)->s_sectors_written_start) >> 1)));82}83 84static ssize_t inode_readahead_blks_store(struct ext4_sb_info *sbi,85 const char *buf, size_t count)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 > 0x40000000))95 return -EINVAL;96 97 sbi->s_inode_readahead_blks = t;98 return count;99}100 101static ssize_t reserved_clusters_store(struct ext4_sb_info *sbi,102 const char *buf, size_t count)103{104 unsigned long long val;105 ext4_fsblk_t clusters = (ext4_blocks_count(sbi->s_es) >>106 sbi->s_cluster_bits);107 int ret;108 109 ret = kstrtoull(skip_spaces(buf), 0, &val);110 if (ret || val >= clusters || (s64)val < 0)111 return -EINVAL;112 113 atomic64_set(&sbi->s_resv_clusters, val);114 return count;115}116 117static ssize_t trigger_test_error(struct ext4_sb_info *sbi,118 const char *buf, size_t count)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", len, buf);130 return count;131}132 133static ssize_t journal_task_show(struct ext4_sb_info *sbi, char *buf)134{135 if (!sbi->s_journal)136 return sysfs_emit(buf, "<none>\n");137 return sysfs_emit(buf, "%d\n",138 task_pid_vnr(sbi->s_journal->j_task));139}140 141#define EXT4_ATTR(_name,_mode,_id) \142static struct ext4_attr ext4_attr_##_name = { \143 .attr = {.name = __stringify(_name), .mode = _mode }, \144 .attr_id = attr_##_id, \145}146 147#define EXT4_ATTR_FUNC(_name,_mode) EXT4_ATTR(_name,_mode,_name)148 149#define EXT4_ATTR_FEATURE(_name) EXT4_ATTR(_name, 0444, feature)150 151#define EXT4_ATTR_OFFSET(_name,_mode,_id,_struct,_elname) \152static struct ext4_attr ext4_attr_##_name = { \153 .attr = {.name = __stringify(_name), .mode = _mode }, \154 .attr_id = attr_##_id, \155 .attr_ptr = ptr_##_struct##_offset, \156 .u = { \157 .offset = offsetof(struct _struct, _elname),\158 }, \159}160 161#define EXT4_ATTR_STRING(_name,_mode,_size,_struct,_elname) \162static struct ext4_attr ext4_attr_##_name = { \163 .attr = {.name = __stringify(_name), .mode = _mode }, \164 .attr_id = attr_pointer_string, \165 .attr_size = _size, \166 .attr_ptr = ptr_##_struct##_offset, \167 .u = { \168 .offset = offsetof(struct _struct, _elname),\169 }, \170}171 172#define EXT4_RO_ATTR_ES_UI(_name,_elname) \173 EXT4_ATTR_OFFSET(_name, 0444, pointer_ui, ext4_super_block, _elname)174 175#define EXT4_RO_ATTR_ES_U8(_name,_elname) \176 EXT4_ATTR_OFFSET(_name, 0444, pointer_u8, ext4_super_block, _elname)177 178#define EXT4_RO_ATTR_ES_U64(_name,_elname) \179 EXT4_ATTR_OFFSET(_name, 0444, pointer_u64, ext4_super_block, _elname)180 181#define EXT4_RO_ATTR_ES_STRING(_name,_elname,_size) \182 EXT4_ATTR_STRING(_name, 0444, _size, ext4_super_block, _elname)183 184#define EXT4_RW_ATTR_SBI_PI(_name,_elname) \185 EXT4_ATTR_OFFSET(_name, 0644, pointer_pi, ext4_sb_info, _elname)186 187#define EXT4_RW_ATTR_SBI_UI(_name,_elname) \188 EXT4_ATTR_OFFSET(_name, 0644, pointer_ui, ext4_sb_info, _elname)189 190#define EXT4_RW_ATTR_SBI_UL(_name,_elname) \191 EXT4_ATTR_OFFSET(_name, 0644, pointer_ul, ext4_sb_info, _elname)192 193#define EXT4_RO_ATTR_SBI_ATOMIC(_name,_elname) \194 EXT4_ATTR_OFFSET(_name, 0444, pointer_atomic, ext4_sb_info, _elname)195 196#define EXT4_ATTR_PTR(_name,_mode,_id,_ptr) \197static struct ext4_attr ext4_attr_##_name = { \198 .attr = {.name = __stringify(_name), .mode = _mode }, \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.attr207 208EXT4_ATTR_FUNC(delayed_allocation_blocks, 0444);209EXT4_ATTR_FUNC(session_write_kbytes, 0444);210EXT4_ATTR_FUNC(lifetime_write_kbytes, 0444);211EXT4_ATTR_FUNC(reserved_clusters, 0644);212EXT4_ATTR_FUNC(sra_exceeded_retry_limit, 0444);213 214EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, inode_readahead,215 ext4_sb_info, s_inode_readahead_blks);216EXT4_ATTR_OFFSET(mb_group_prealloc, 0644, clusters_in_group,217 ext4_sb_info, s_mb_group_prealloc);218EXT4_ATTR_OFFSET(mb_best_avail_max_trim_order, 0644, mb_order,219 ext4_sb_info, s_mb_best_avail_max_trim_order);220EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);221EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);222EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);223EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);224EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);225EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);226EXT4_RW_ATTR_SBI_UI(mb_max_linear_groups, s_mb_max_linear_groups);227EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb);228EXT4_ATTR(trigger_fs_error, 0200, trigger_test_error);229EXT4_RW_ATTR_SBI_PI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval);230EXT4_RW_ATTR_SBI_PI(err_ratelimit_burst, s_err_ratelimit_state.burst);231EXT4_RW_ATTR_SBI_PI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval);232EXT4_RW_ATTR_SBI_PI(warning_ratelimit_burst, s_warning_ratelimit_state.burst);233EXT4_RW_ATTR_SBI_PI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval);234EXT4_RW_ATTR_SBI_PI(msg_ratelimit_burst, s_msg_ratelimit_state.burst);235#ifdef CONFIG_EXT4_DEBUG236EXT4_RW_ATTR_SBI_UL(simulate_fail, s_simulate_fail);237#endif238EXT4_RO_ATTR_SBI_ATOMIC(warning_count, s_warning_count);239EXT4_RO_ATTR_SBI_ATOMIC(msg_count, s_msg_count);240EXT4_RO_ATTR_ES_UI(errors_count, s_error_count);241EXT4_RO_ATTR_ES_U8(first_error_errcode, s_first_error_errcode);242EXT4_RO_ATTR_ES_U8(last_error_errcode, s_last_error_errcode);243EXT4_RO_ATTR_ES_UI(first_error_ino, s_first_error_ino);244EXT4_RO_ATTR_ES_UI(last_error_ino, s_last_error_ino);245EXT4_RO_ATTR_ES_U64(first_error_block, s_first_error_block);246EXT4_RO_ATTR_ES_U64(last_error_block, s_last_error_block);247EXT4_RO_ATTR_ES_UI(first_error_line, s_first_error_line);248EXT4_RO_ATTR_ES_UI(last_error_line, s_last_error_line);249EXT4_RO_ATTR_ES_STRING(first_error_func, s_first_error_func, 32);250EXT4_RO_ATTR_ES_STRING(last_error_func, s_last_error_func, 32);251EXT4_ATTR(first_error_time, 0444, first_error_time);252EXT4_ATTR(last_error_time, 0444, last_error_time);253EXT4_ATTR(journal_task, 0444, journal_task);254EXT4_RW_ATTR_SBI_UI(mb_prefetch, s_mb_prefetch);255EXT4_RW_ATTR_SBI_UI(mb_prefetch_limit, s_mb_prefetch_limit);256EXT4_RW_ATTR_SBI_UL(last_trim_minblks, s_last_trim_minblks);257 258static unsigned int old_bump_val = 128;259EXT4_ATTR_PTR(max_writeback_mb_bump, 0444, pointer_ui, &old_bump_val);260 261static 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_ms),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_DEBUG303 ATTR_LIST(simulate_fail),304#endif305 ATTR_LIST(mb_prefetch),306 ATTR_LIST(mb_prefetch_limit),307 ATTR_LIST(last_trim_minblks),308 NULL,309};310ATTRIBUTE_GROUPS(ext4);311 312/* Features this copy of ext4 supports */313EXT4_ATTR_FEATURE(lazy_itable_init);314EXT4_ATTR_FEATURE(batched_discard);315EXT4_ATTR_FEATURE(meta_bg_resize);316#ifdef CONFIG_FS_ENCRYPTION317EXT4_ATTR_FEATURE(encryption);318EXT4_ATTR_FEATURE(test_dummy_encryption_v2);319#endif320#if IS_ENABLED(CONFIG_UNICODE)321EXT4_ATTR_FEATURE(casefold);322#endif323#ifdef CONFIG_FS_VERITY324EXT4_ATTR_FEATURE(verity);325#endif326EXT4_ATTR_FEATURE(metadata_csum_seed);327EXT4_ATTR_FEATURE(fast_commit);328#if IS_ENABLED(CONFIG_UNICODE) && defined(CONFIG_FS_ENCRYPTION)329EXT4_ATTR_FEATURE(encrypted_casefold);330#endif331 332static 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_ENCRYPTION337 ATTR_LIST(encryption),338 ATTR_LIST(test_dummy_encryption_v2),339#endif340#if IS_ENABLED(CONFIG_UNICODE)341 ATTR_LIST(casefold),342#endif343#ifdef CONFIG_FS_VERITY344 ATTR_LIST(verity),345#endif346 ATTR_LIST(metadata_csum_seed),347 ATTR_LIST(fast_commit),348#if IS_ENABLED(CONFIG_UNICODE) && defined(CONFIG_FS_ENCRYPTION)349 ATTR_LIST(encrypted_casefold),350#endif351 NULL,352};353ATTRIBUTE_GROUPS(ext4_feat);354 355static void *calc_ptr(struct ext4_attr *a, struct ext4_sb_info *sbi)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) + a->u.offset);362 case ptr_ext4_super_block_offset:363 return (void *) (((char *) sbi->s_es) + a->u.offset);364 }365 return NULL;366}367 368static ssize_t __print_tstamp(char *buf, __le32 lo, __u8 hi)369{370 return sysfs_emit(buf, "%lld\n",371 ((time64_t)hi << 32) + le32_to_cpu(lo));372}373 374#define print_tstamp(buf, es, tstamp) \375 __print_tstamp(buf, (es)->tstamp, (es)->tstamp ## _hi)376 377static ssize_t ext4_generic_attr_show(struct ext4_attr *a,378 struct ext4_sb_info *sbi, char *buf)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_super_block_offset)392 return sysfs_emit(buf, "%u\n", le32_to_cpup(ptr));393 return sysfs_emit(buf, "%u\n", *((unsigned int *) ptr));394 case attr_pointer_ul:395 return sysfs_emit(buf, "%lu\n", *((unsigned long *) ptr));396 case attr_pointer_u8:397 return sysfs_emit(buf, "%u\n", *((unsigned char *) ptr));398 case attr_pointer_u64:399 if (a->attr_ptr == ptr_ext4_super_block_offset)400 return sysfs_emit(buf, "%llu\n", le64_to_cpup(ptr));401 return sysfs_emit(buf, "%llu\n", *((unsigned long long *) ptr));402 case attr_pointer_string:403 return sysfs_emit(buf, "%.*s\n", a->attr_size, (char *) ptr);404 case attr_pointer_atomic:405 return sysfs_emit(buf, "%d\n", atomic_read((atomic_t *) ptr));406 }407 return 0;408}409 410static ssize_t ext4_attr_show(struct kobject *kobj,411 struct attribute *attr, char *buf)412{413 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,414 s_kobj);415 struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);416 417 switch (a->attr_id) {418 case attr_delayed_allocation_blocks:419 return sysfs_emit(buf, "%llu\n",420 (s64) EXT4_C2B(sbi,421 percpu_counter_sum(&sbi->s_dirtyclusters_counter)));422 case attr_session_write_kbytes:423 return session_write_kbytes_show(sbi, buf);424 case attr_lifetime_write_kbytes:425 return lifetime_write_kbytes_show(sbi, buf);426 case attr_reserved_clusters:427 return sysfs_emit(buf, "%llu\n",428 (unsigned long long)429 atomic64_read(&sbi->s_resv_clusters));430 case attr_sra_exceeded_retry_limit:431 return sysfs_emit(buf, "%llu\n",432 (unsigned long long)433 percpu_counter_sum(&sbi->s_sra_exceeded_retry_limit));434 case attr_feature:435 return sysfs_emit(buf, "supported\n");436 case attr_first_error_time:437 return print_tstamp(buf, sbi->s_es, s_first_error_time);438 case attr_last_error_time:439 return print_tstamp(buf, sbi->s_es, s_last_error_time);440 case attr_journal_task:441 return journal_task_show(sbi, buf);442 default:443 return ext4_generic_attr_show(a, sbi, buf);444 }445}446 447static ssize_t ext4_generic_attr_store(struct ext4_attr *a,448 struct ext4_sb_info *sbi,449 const char *buf, size_t len)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(buf), 0, &t);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(buf), 0, &t);470 if (ret)471 return ret;472 if (a->attr_ptr == ptr_ext4_super_block_offset)473 *((__le32 *) ptr) = cpu_to_le32(t);474 else475 *((unsigned int *) ptr) = t;476 return len;477 case attr_mb_order:478 ret = kstrtouint(skip_spaces(buf), 0, &t);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(buf), 0, &t);487 if (ret)488 return ret;489 if (t > sbi->s_clusters_per_group)490 return -EINVAL;491 *((unsigned int *) ptr) = t;492 return len;493 case attr_pointer_ul:494 ret = kstrtoul(skip_spaces(buf), 0, <);495 if (ret)496 return ret;497 *((unsigned long *) ptr) = lt;498 return len;499 }500 return 0;501}502 503static ssize_t ext4_attr_store(struct kobject *kobj,504 struct attribute *attr,505 const char *buf, size_t len)506{507 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,508 s_kobj);509 struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);510 511 switch (a->attr_id) {512 case attr_reserved_clusters:513 return reserved_clusters_store(sbi, buf, len);514 case attr_inode_readahead:515 return inode_readahead_blks_store(sbi, buf, len);516 case attr_trigger_test_error:517 return trigger_test_error(sbi, buf, len);518 default:519 return ext4_generic_attr_store(a, sbi, buf, len);520 }521}522 523static void ext4_sb_release(struct kobject *kobj)524{525 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,526 s_kobj);527 complete(&sbi->s_kobj_unregister);528}529 530static void ext4_feat_release(struct kobject *kobj)531{532 kfree(kobj);533}534 535static const struct sysfs_ops ext4_attr_ops = {536 .show = ext4_attr_show,537 .store = ext4_attr_store,538};539 540static 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 546static 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 552void ext4_notify_error_sysfs(struct ext4_sb_info *sbi)553{554 sysfs_notify(&sbi->s_kobj, NULL, "errors_count");555}556 557static struct kobject *ext4_root;558 559static struct kobject *ext4_feat;560 561int 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_unregister);567 err = kobject_init_and_add(&sbi->s_kobj, &ext4_sb_ktype, ext4_root,568 "%s", sb->s_id);569 if (err) {570 kobject_put(&sbi->s_kobj);571 wait_for_completion(&sbi->s_kobj_unregister);572 return err;573 }574 575 if (ext4_proc_root)576 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);577 if (sbi->s_proc) {578 proc_create_single_data("options", S_IRUGO, sbi->s_proc,579 ext4_seq_options_show, sb);580 proc_create_single_data("es_shrinker_info", S_IRUGO,581 sbi->s_proc, ext4_seq_es_shrinker_info_show,582 sb);583 proc_create_single_data("fc_info", 0444, sbi->s_proc,584 ext4_fc_info_show, sb);585 proc_create_seq_data("mb_groups", S_IRUGO, sbi->s_proc,586 &ext4_mb_seq_groups_ops, sb);587 proc_create_single_data("mb_stats", 0444, sbi->s_proc,588 ext4_seq_mb_stats_show, sb);589 proc_create_seq_data("mb_structs_summary", 0444, sbi->s_proc,590 &ext4_mb_seq_structs_summary_ops, sb);591 }592 return 0;593}594 595void ext4_unregister_sysfs(struct super_block *sb)596{597 struct ext4_sb_info *sbi = EXT4_SB(sb);598 599 if (sbi->s_proc)600 remove_proc_subtree(sb->s_id, ext4_proc_root);601 kobject_del(&sbi->s_kobj);602}603 604int __init ext4_init_sysfs(void)605{606 int ret;607 608 ext4_root = kobject_create_and_add("ext4", fs_kobj);609 if (!ext4_root)610 return -ENOMEM;611 612 ext4_feat = kzalloc(sizeof(*ext4_feat), GFP_KERNEL);613 if (!ext4_feat) {614 ret = -ENOMEM;615 goto root_err;616 }617 618 ret = kobject_init_and_add(ext4_feat, &ext4_feat_ktype,619 ext4_root, "features");620 if (ret)621 goto feat_err;622 623 ext4_proc_root = proc_mkdir(proc_dirname, NULL);624 return ret;625 626feat_err:627 kobject_put(ext4_feat);628 ext4_feat = NULL;629root_err:630 kobject_put(ext4_root);631 ext4_root = NULL;632 return ret;633}634 635void 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