1 // SPDX-License-Identifier: GPL-2.0 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_feature, 33 attr_pointer_ui, 34 attr_pointer_ul, 35 attr_pointer_u64, 36 attr_pointer_u8, 37 attr_pointer_string, 38 attr_pointer_atomic, 39 attr_journal_task, 40 } attr_id_t; 41 42 typedef enum { 43 ptr_explicit, 44 ptr_ext4_sb_info_offset, 45 ptr_ext4_super_block_offset, 46 } attr_ptr_t; 47 48 static const char proc_dirname[] = "fs/ext4"; 49 static struct proc_dir_entry *ext4_proc_root; 50 51 struct ext4_attr { 52 struct attribute attr; 53 short attr_id; 54 short attr_ptr; 55 unsigned short attr_size; 56 union { 57 int offset; 58 void *explicit_ptr; 59 } u; 60 }; 61 62 static ssize_t session_write_kbytes_show(struct ext4_sb_info *sbi, char *buf) 63 { 64 struct super_block *sb = sbi->s_buddy_cache->i_sb; 65 66 return snprintf(buf, PAGE_SIZE, "%lu\n", 67 (part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) - 68 sbi->s_sectors_written_start) >> 1); 69 } 70 71 static ssize_t lifetime_write_kbytes_show(struct ext4_sb_info *sbi, char *buf) 72 { 73 struct super_block *sb = sbi->s_buddy_cache->i_sb; 74 75 return snprintf(buf, PAGE_SIZE, "%llu\n", 76 (unsigned long long)(sbi->s_kbytes_written + 77 ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) - 78 EXT4_SB(sb)->s_sectors_written_start) >> 1))); 79 } 80 81 static ssize_t inode_readahead_blks_store(struct ext4_sb_info *sbi, 82 const char *buf, size_t count) 83 { 84 unsigned long t; 85 int ret; 86 87 ret = kstrtoul(skip_spaces(buf), 0, &t); 88 if (ret) 89 return ret; 90 91 if (t && (!is_power_of_2(t) || t > 0x40000000)) 92 return -EINVAL; 93 94 sbi->s_inode_readahead_blks = t; 95 return count; 96 } 97 98 static ssize_t reserved_clusters_store(struct ext4_sb_info *sbi, 99 const char *buf, size_t count) 100 { 101 unsigned long long val; 102 ext4_fsblk_t clusters = (ext4_blocks_count(sbi->s_es) >> 103 sbi->s_cluster_bits); 104 int ret; 105 106 ret = kstrtoull(skip_spaces(buf), 0, &val); 107 if (ret || val >= clusters) 108 return -EINVAL; 109 110 atomic64_set(&sbi->s_resv_clusters, val); 111 return count; 112 } 113 114 static ssize_t trigger_test_error(struct ext4_sb_info *sbi, 115 const char *buf, size_t count) 116 { 117 int len = count; 118 119 if (!capable(CAP_SYS_ADMIN)) 120 return -EPERM; 121 122 if (len && buf[len-1] == '\n') 123 len--; 124 125 if (len) 126 ext4_error(sbi->s_sb, "%.*s", len, buf); 127 return count; 128 } 129 130 static ssize_t journal_task_show(struct ext4_sb_info *sbi, char *buf) 131 { 132 if (!sbi->s_journal) 133 return snprintf(buf, PAGE_SIZE, "<none>\n"); 134 return snprintf(buf, PAGE_SIZE, "%d\n", 135 task_pid_vnr(sbi->s_journal->j_task)); 136 } 137 138 #define EXT4_ATTR(_name,_mode,_id) \ 139 static struct ext4_attr ext4_attr_##_name = { \ 140 .attr = {.name = __stringify(_name), .mode = _mode }, \ 141 .attr_id = attr_##_id, \ 142 } 143 144 #define EXT4_ATTR_FUNC(_name,_mode) EXT4_ATTR(_name,_mode,_name) 145 146 #define EXT4_ATTR_FEATURE(_name) EXT4_ATTR(_name, 0444, feature) 147 148 #define EXT4_ATTR_OFFSET(_name,_mode,_id,_struct,_elname) \ 149 static struct ext4_attr ext4_attr_##_name = { \ 150 .attr = {.name = __stringify(_name), .mode = _mode }, \ 151 .attr_id = attr_##_id, \ 152 .attr_ptr = ptr_##_struct##_offset, \ 153 .u = { \ 154 .offset = offsetof(struct _struct, _elname),\ 155 }, \ 156 } 157 158 #define EXT4_ATTR_STRING(_name,_mode,_size,_struct,_elname) \ 159 static struct ext4_attr ext4_attr_##_name = { \ 160 .attr = {.name = __stringify(_name), .mode = _mode }, \ 161 .attr_id = attr_pointer_string, \ 162 .attr_size = _size, \ 163 .attr_ptr = ptr_##_struct##_offset, \ 164 .u = { \ 165 .offset = offsetof(struct _struct, _elname),\ 166 }, \ 167 } 168 169 #define EXT4_RO_ATTR_ES_UI(_name,_elname) \ 170 EXT4_ATTR_OFFSET(_name, 0444, pointer_ui, ext4_super_block, _elname) 171 172 #define EXT4_RO_ATTR_ES_U8(_name,_elname) \ 173 EXT4_ATTR_OFFSET(_name, 0444, pointer_u8, ext4_super_block, _elname) 174 175 #define EXT4_RO_ATTR_ES_U64(_name,_elname) \ 176 EXT4_ATTR_OFFSET(_name, 0444, pointer_u64, ext4_super_block, _elname) 177 178 #define EXT4_RO_ATTR_ES_STRING(_name,_elname,_size) \ 179 EXT4_ATTR_STRING(_name, 0444, _size, ext4_super_block, _elname) 180 181 #define EXT4_RW_ATTR_SBI_UI(_name,_elname) \ 182 EXT4_ATTR_OFFSET(_name, 0644, pointer_ui, ext4_sb_info, _elname) 183 184 #define EXT4_RW_ATTR_SBI_UL(_name,_elname) \ 185 EXT4_ATTR_OFFSET(_name, 0644, pointer_ul, ext4_sb_info, _elname) 186 187 #define EXT4_RO_ATTR_SBI_ATOMIC(_name,_elname) \ 188 EXT4_ATTR_OFFSET(_name, 0444, pointer_atomic, ext4_sb_info, _elname) 189 190 #define EXT4_ATTR_PTR(_name,_mode,_id,_ptr) \ 191 static struct ext4_attr ext4_attr_##_name = { \ 192 .attr = {.name = __stringify(_name), .mode = _mode }, \ 193 .attr_id = attr_##_id, \ 194 .attr_ptr = ptr_explicit, \ 195 .u = { \ 196 .explicit_ptr = _ptr, \ 197 }, \ 198 } 199 200 #define ATTR_LIST(name) &ext4_attr_##name.attr 201 202 EXT4_ATTR_FUNC(delayed_allocation_blocks, 0444); 203 EXT4_ATTR_FUNC(session_write_kbytes, 0444); 204 EXT4_ATTR_FUNC(lifetime_write_kbytes, 0444); 205 EXT4_ATTR_FUNC(reserved_clusters, 0644); 206 EXT4_ATTR_FUNC(sra_exceeded_retry_limit, 0444); 207 208 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, inode_readahead, 209 ext4_sb_info, s_inode_readahead_blks); 210 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal); 211 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats); 212 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan); 213 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan); 214 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs); 215 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request); 216 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc); 217 EXT4_RW_ATTR_SBI_UI(mb_max_inode_prealloc, s_mb_max_inode_prealloc); 218 EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb); 219 EXT4_ATTR(trigger_fs_error, 0200, trigger_test_error); 220 EXT4_RW_ATTR_SBI_UI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval); 221 EXT4_RW_ATTR_SBI_UI(err_ratelimit_burst, s_err_ratelimit_state.burst); 222 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval); 223 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_burst, s_warning_ratelimit_state.burst); 224 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval); 225 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_burst, s_msg_ratelimit_state.burst); 226 #ifdef CONFIG_EXT4_DEBUG 227 EXT4_RW_ATTR_SBI_UL(simulate_fail, s_simulate_fail); 228 #endif 229 EXT4_RO_ATTR_SBI_ATOMIC(warning_count, s_warning_count); 230 EXT4_RO_ATTR_SBI_ATOMIC(msg_count, s_msg_count); 231 EXT4_RO_ATTR_ES_UI(errors_count, s_error_count); 232 EXT4_RO_ATTR_ES_U8(first_error_errcode, s_first_error_errcode); 233 EXT4_RO_ATTR_ES_U8(last_error_errcode, s_last_error_errcode); 234 EXT4_RO_ATTR_ES_UI(first_error_ino, s_first_error_ino); 235 EXT4_RO_ATTR_ES_UI(last_error_ino, s_last_error_ino); 236 EXT4_RO_ATTR_ES_U64(first_error_block, s_first_error_block); 237 EXT4_RO_ATTR_ES_U64(last_error_block, s_last_error_block); 238 EXT4_RO_ATTR_ES_UI(first_error_line, s_first_error_line); 239 EXT4_RO_ATTR_ES_UI(last_error_line, s_last_error_line); 240 EXT4_RO_ATTR_ES_STRING(first_error_func, s_first_error_func, 32); 241 EXT4_RO_ATTR_ES_STRING(last_error_func, s_last_error_func, 32); 242 EXT4_ATTR(first_error_time, 0444, first_error_time); 243 EXT4_ATTR(last_error_time, 0444, last_error_time); 244 EXT4_ATTR(journal_task, 0444, journal_task); 245 EXT4_RW_ATTR_SBI_UI(mb_prefetch, s_mb_prefetch); 246 EXT4_RW_ATTR_SBI_UI(mb_prefetch_limit, s_mb_prefetch_limit); 247 248 static unsigned int old_bump_val = 128; 249 EXT4_ATTR_PTR(max_writeback_mb_bump, 0444, pointer_ui, &old_bump_val); 250 251 static struct attribute *ext4_attrs[] = { 252 ATTR_LIST(delayed_allocation_blocks), 253 ATTR_LIST(session_write_kbytes), 254 ATTR_LIST(lifetime_write_kbytes), 255 ATTR_LIST(reserved_clusters), 256 ATTR_LIST(sra_exceeded_retry_limit), 257 ATTR_LIST(inode_readahead_blks), 258 ATTR_LIST(inode_goal), 259 ATTR_LIST(mb_stats), 260 ATTR_LIST(mb_max_to_scan), 261 ATTR_LIST(mb_min_to_scan), 262 ATTR_LIST(mb_order2_req), 263 ATTR_LIST(mb_stream_req), 264 ATTR_LIST(mb_group_prealloc), 265 ATTR_LIST(mb_max_inode_prealloc), 266 ATTR_LIST(max_writeback_mb_bump), 267 ATTR_LIST(extent_max_zeroout_kb), 268 ATTR_LIST(trigger_fs_error), 269 ATTR_LIST(err_ratelimit_interval_ms), 270 ATTR_LIST(err_ratelimit_burst), 271 ATTR_LIST(warning_ratelimit_interval_ms), 272 ATTR_LIST(warning_ratelimit_burst), 273 ATTR_LIST(msg_ratelimit_interval_ms), 274 ATTR_LIST(msg_ratelimit_burst), 275 ATTR_LIST(errors_count), 276 ATTR_LIST(warning_count), 277 ATTR_LIST(msg_count), 278 ATTR_LIST(first_error_ino), 279 ATTR_LIST(last_error_ino), 280 ATTR_LIST(first_error_block), 281 ATTR_LIST(last_error_block), 282 ATTR_LIST(first_error_line), 283 ATTR_LIST(last_error_line), 284 ATTR_LIST(first_error_func), 285 ATTR_LIST(last_error_func), 286 ATTR_LIST(first_error_errcode), 287 ATTR_LIST(last_error_errcode), 288 ATTR_LIST(first_error_time), 289 ATTR_LIST(last_error_time), 290 ATTR_LIST(journal_task), 291 #ifdef CONFIG_EXT4_DEBUG 292 ATTR_LIST(simulate_fail), 293 #endif 294 ATTR_LIST(mb_prefetch), 295 ATTR_LIST(mb_prefetch_limit), 296 NULL, 297 }; 298 ATTRIBUTE_GROUPS(ext4); 299 300 /* Features this copy of ext4 supports */ 301 EXT4_ATTR_FEATURE(lazy_itable_init); 302 EXT4_ATTR_FEATURE(batched_discard); 303 EXT4_ATTR_FEATURE(meta_bg_resize); 304 #ifdef CONFIG_FS_ENCRYPTION 305 EXT4_ATTR_FEATURE(encryption); 306 EXT4_ATTR_FEATURE(test_dummy_encryption_v2); 307 #endif 308 #ifdef CONFIG_UNICODE 309 EXT4_ATTR_FEATURE(casefold); 310 #endif 311 #ifdef CONFIG_FS_VERITY 312 EXT4_ATTR_FEATURE(verity); 313 #endif 314 EXT4_ATTR_FEATURE(metadata_csum_seed); 315 EXT4_ATTR_FEATURE(fast_commit); 316 317 static struct attribute *ext4_feat_attrs[] = { 318 ATTR_LIST(lazy_itable_init), 319 ATTR_LIST(batched_discard), 320 ATTR_LIST(meta_bg_resize), 321 #ifdef CONFIG_FS_ENCRYPTION 322 ATTR_LIST(encryption), 323 ATTR_LIST(test_dummy_encryption_v2), 324 #endif 325 #ifdef CONFIG_UNICODE 326 ATTR_LIST(casefold), 327 #endif 328 #ifdef CONFIG_FS_VERITY 329 ATTR_LIST(verity), 330 #endif 331 ATTR_LIST(metadata_csum_seed), 332 ATTR_LIST(fast_commit), 333 NULL, 334 }; 335 ATTRIBUTE_GROUPS(ext4_feat); 336 337 static void *calc_ptr(struct ext4_attr *a, struct ext4_sb_info *sbi) 338 { 339 switch (a->attr_ptr) { 340 case ptr_explicit: 341 return a->u.explicit_ptr; 342 case ptr_ext4_sb_info_offset: 343 return (void *) (((char *) sbi) + a->u.offset); 344 case ptr_ext4_super_block_offset: 345 return (void *) (((char *) sbi->s_es) + a->u.offset); 346 } 347 return NULL; 348 } 349 350 static ssize_t __print_tstamp(char *buf, __le32 lo, __u8 hi) 351 { 352 return snprintf(buf, PAGE_SIZE, "%lld\n", 353 ((time64_t)hi << 32) + le32_to_cpu(lo)); 354 } 355 356 #define print_tstamp(buf, es, tstamp) \ 357 __print_tstamp(buf, (es)->tstamp, (es)->tstamp ## _hi) 358 359 static ssize_t ext4_attr_show(struct kobject *kobj, 360 struct attribute *attr, char *buf) 361 { 362 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info, 363 s_kobj); 364 struct ext4_attr *a = container_of(attr, struct ext4_attr, attr); 365 void *ptr = calc_ptr(a, sbi); 366 367 switch (a->attr_id) { 368 case attr_delayed_allocation_blocks: 369 return snprintf(buf, PAGE_SIZE, "%llu\n", 370 (s64) EXT4_C2B(sbi, 371 percpu_counter_sum(&sbi->s_dirtyclusters_counter))); 372 case attr_session_write_kbytes: 373 return session_write_kbytes_show(sbi, buf); 374 case attr_lifetime_write_kbytes: 375 return lifetime_write_kbytes_show(sbi, buf); 376 case attr_reserved_clusters: 377 return snprintf(buf, PAGE_SIZE, "%llu\n", 378 (unsigned long long) 379 atomic64_read(&sbi->s_resv_clusters)); 380 case attr_sra_exceeded_retry_limit: 381 return snprintf(buf, PAGE_SIZE, "%llu\n", 382 (unsigned long long) 383 percpu_counter_sum(&sbi->s_sra_exceeded_retry_limit)); 384 case attr_inode_readahead: 385 case attr_pointer_ui: 386 if (!ptr) 387 return 0; 388 if (a->attr_ptr == ptr_ext4_super_block_offset) 389 return snprintf(buf, PAGE_SIZE, "%u\n", 390 le32_to_cpup(ptr)); 391 else 392 return snprintf(buf, PAGE_SIZE, "%u\n", 393 *((unsigned int *) ptr)); 394 case attr_pointer_ul: 395 if (!ptr) 396 return 0; 397 return snprintf(buf, PAGE_SIZE, "%lu\n", 398 *((unsigned long *) ptr)); 399 case attr_pointer_u8: 400 if (!ptr) 401 return 0; 402 return snprintf(buf, PAGE_SIZE, "%u\n", 403 *((unsigned char *) ptr)); 404 case attr_pointer_u64: 405 if (!ptr) 406 return 0; 407 if (a->attr_ptr == ptr_ext4_super_block_offset) 408 return snprintf(buf, PAGE_SIZE, "%llu\n", 409 le64_to_cpup(ptr)); 410 else 411 return snprintf(buf, PAGE_SIZE, "%llu\n", 412 *((unsigned long long *) ptr)); 413 case attr_pointer_string: 414 if (!ptr) 415 return 0; 416 return snprintf(buf, PAGE_SIZE, "%.*s\n", a->attr_size, 417 (char *) ptr); 418 case attr_pointer_atomic: 419 if (!ptr) 420 return 0; 421 return snprintf(buf, PAGE_SIZE, "%d\n", 422 atomic_read((atomic_t *) ptr)); 423 case attr_feature: 424 return snprintf(buf, PAGE_SIZE, "supported\n"); 425 case attr_first_error_time: 426 return print_tstamp(buf, sbi->s_es, s_first_error_time); 427 case attr_last_error_time: 428 return print_tstamp(buf, sbi->s_es, s_last_error_time); 429 case attr_journal_task: 430 return journal_task_show(sbi, buf); 431 } 432 433 return 0; 434 } 435 436 static ssize_t ext4_attr_store(struct kobject *kobj, 437 struct attribute *attr, 438 const char *buf, size_t len) 439 { 440 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info, 441 s_kobj); 442 struct ext4_attr *a = container_of(attr, struct ext4_attr, attr); 443 void *ptr = calc_ptr(a, sbi); 444 unsigned long t; 445 int ret; 446 447 switch (a->attr_id) { 448 case attr_reserved_clusters: 449 return reserved_clusters_store(sbi, buf, len); 450 case attr_pointer_ui: 451 if (!ptr) 452 return 0; 453 ret = kstrtoul(skip_spaces(buf), 0, &t); 454 if (ret) 455 return ret; 456 if (a->attr_ptr == ptr_ext4_super_block_offset) 457 *((__le32 *) ptr) = cpu_to_le32(t); 458 else 459 *((unsigned int *) ptr) = t; 460 return len; 461 case attr_pointer_ul: 462 if (!ptr) 463 return 0; 464 ret = kstrtoul(skip_spaces(buf), 0, &t); 465 if (ret) 466 return ret; 467 *((unsigned long *) ptr) = t; 468 return len; 469 case attr_inode_readahead: 470 return inode_readahead_blks_store(sbi, buf, len); 471 case attr_trigger_test_error: 472 return trigger_test_error(sbi, buf, len); 473 } 474 return 0; 475 } 476 477 static void ext4_sb_release(struct kobject *kobj) 478 { 479 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info, 480 s_kobj); 481 complete(&sbi->s_kobj_unregister); 482 } 483 484 static const struct sysfs_ops ext4_attr_ops = { 485 .show = ext4_attr_show, 486 .store = ext4_attr_store, 487 }; 488 489 static struct kobj_type ext4_sb_ktype = { 490 .default_groups = ext4_groups, 491 .sysfs_ops = &ext4_attr_ops, 492 .release = ext4_sb_release, 493 }; 494 495 static struct kobj_type ext4_feat_ktype = { 496 .default_groups = ext4_feat_groups, 497 .sysfs_ops = &ext4_attr_ops, 498 .release = (void (*)(struct kobject *))kfree, 499 }; 500 501 static struct kobject *ext4_root; 502 503 static struct kobject *ext4_feat; 504 505 int ext4_register_sysfs(struct super_block *sb) 506 { 507 struct ext4_sb_info *sbi = EXT4_SB(sb); 508 int err; 509 510 init_completion(&sbi->s_kobj_unregister); 511 err = kobject_init_and_add(&sbi->s_kobj, &ext4_sb_ktype, ext4_root, 512 "%s", sb->s_id); 513 if (err) { 514 kobject_put(&sbi->s_kobj); 515 wait_for_completion(&sbi->s_kobj_unregister); 516 return err; 517 } 518 519 if (ext4_proc_root) 520 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root); 521 if (sbi->s_proc) { 522 proc_create_single_data("options", S_IRUGO, sbi->s_proc, 523 ext4_seq_options_show, sb); 524 proc_create_single_data("es_shrinker_info", S_IRUGO, 525 sbi->s_proc, ext4_seq_es_shrinker_info_show, 526 sb); 527 proc_create_single_data("fc_info", 0444, sbi->s_proc, 528 ext4_fc_info_show, sb); 529 proc_create_seq_data("mb_groups", S_IRUGO, sbi->s_proc, 530 &ext4_mb_seq_groups_ops, sb); 531 } 532 return 0; 533 } 534 535 void ext4_unregister_sysfs(struct super_block *sb) 536 { 537 struct ext4_sb_info *sbi = EXT4_SB(sb); 538 539 if (sbi->s_proc) 540 remove_proc_subtree(sb->s_id, ext4_proc_root); 541 kobject_del(&sbi->s_kobj); 542 } 543 544 int __init ext4_init_sysfs(void) 545 { 546 int ret; 547 548 ext4_root = kobject_create_and_add("ext4", fs_kobj); 549 if (!ext4_root) 550 return -ENOMEM; 551 552 ext4_feat = kzalloc(sizeof(*ext4_feat), GFP_KERNEL); 553 if (!ext4_feat) { 554 ret = -ENOMEM; 555 goto root_err; 556 } 557 558 ret = kobject_init_and_add(ext4_feat, &ext4_feat_ktype, 559 ext4_root, "features"); 560 if (ret) 561 goto feat_err; 562 563 ext4_proc_root = proc_mkdir(proc_dirname, NULL); 564 return ret; 565 566 feat_err: 567 kobject_put(ext4_feat); 568 ext4_feat = NULL; 569 root_err: 570 kobject_put(ext4_root); 571 ext4_root = NULL; 572 return ret; 573 } 574 575 void ext4_exit_sysfs(void) 576 { 577 kobject_put(ext4_feat); 578 ext4_feat = NULL; 579 kobject_put(ext4_root); 580 ext4_root = NULL; 581 remove_proc_entry(proc_dirname, NULL); 582 ext4_proc_root = NULL; 583 } 584 585