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_inode_readahead, 28 attr_trigger_test_error, 29 attr_first_error_time, 30 attr_last_error_time, 31 attr_feature, 32 attr_pointer_ui, 33 attr_pointer_ul, 34 attr_pointer_u64, 35 attr_pointer_u8, 36 attr_pointer_string, 37 attr_pointer_atomic, 38 attr_journal_task, 39 } attr_id_t; 40 41 typedef enum { 42 ptr_explicit, 43 ptr_ext4_sb_info_offset, 44 ptr_ext4_super_block_offset, 45 } attr_ptr_t; 46 47 static const char proc_dirname[] = "fs/ext4"; 48 static struct proc_dir_entry *ext4_proc_root; 49 50 struct ext4_attr { 51 struct attribute attr; 52 short attr_id; 53 short attr_ptr; 54 unsigned short attr_size; 55 union { 56 int offset; 57 void *explicit_ptr; 58 } u; 59 }; 60 61 static ssize_t session_write_kbytes_show(struct ext4_sb_info *sbi, char *buf) 62 { 63 struct super_block *sb = sbi->s_buddy_cache->i_sb; 64 65 return snprintf(buf, PAGE_SIZE, "%lu\n", 66 (part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) - 67 sbi->s_sectors_written_start) >> 1); 68 } 69 70 static ssize_t lifetime_write_kbytes_show(struct ext4_sb_info *sbi, char *buf) 71 { 72 struct super_block *sb = sbi->s_buddy_cache->i_sb; 73 74 return snprintf(buf, PAGE_SIZE, "%llu\n", 75 (unsigned long long)(sbi->s_kbytes_written + 76 ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) - 77 EXT4_SB(sb)->s_sectors_written_start) >> 1))); 78 } 79 80 static ssize_t inode_readahead_blks_store(struct ext4_sb_info *sbi, 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 97 static ssize_t reserved_clusters_store(struct ext4_sb_info *sbi, 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); 103 int ret; 104 105 ret = kstrtoull(skip_spaces(buf), 0, &val); 106 if (ret || val >= clusters) 107 return -EINVAL; 108 109 atomic64_set(&sbi->s_resv_clusters, val); 110 return count; 111 } 112 113 static ssize_t trigger_test_error(struct ext4_sb_info *sbi, 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 } 128 129 static 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 } 136 137 #define EXT4_ATTR(_name,_mode,_id) \ 138 static struct ext4_attr ext4_attr_##_name = { \ 139 .attr = {.name = __stringify(_name), .mode = _mode }, \ 140 .attr_id = attr_##_id, \ 141 } 142 143 #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) \ 148 static struct ext4_attr ext4_attr_##_name = { \ 149 .attr = {.name = __stringify(_name), .mode = _mode }, \ 150 .attr_id = attr_##_id, \ 151 .attr_ptr = ptr_##_struct##_offset, \ 152 .u = { \ 153 .offset = offsetof(struct _struct, _elname),\ 154 }, \ 155 } 156 157 #define EXT4_ATTR_STRING(_name,_mode,_size,_struct,_elname) \ 158 static struct ext4_attr ext4_attr_##_name = { \ 159 .attr = {.name = __stringify(_name), .mode = _mode }, \ 160 .attr_id = attr_pointer_string, \ 161 .attr_size = _size, \ 162 .attr_ptr = ptr_##_struct##_offset, \ 163 .u = { \ 164 .offset = offsetof(struct _struct, _elname),\ 165 }, \ 166 } 167 168 #define EXT4_RO_ATTR_ES_UI(_name,_elname) \ 169 EXT4_ATTR_OFFSET(_name, 0444, pointer_ui, ext4_super_block, _elname) 170 171 #define EXT4_RO_ATTR_ES_U8(_name,_elname) \ 172 EXT4_ATTR_OFFSET(_name, 0444, pointer_u8, ext4_super_block, _elname) 173 174 #define EXT4_RO_ATTR_ES_U64(_name,_elname) \ 175 EXT4_ATTR_OFFSET(_name, 0444, pointer_u64, ext4_super_block, _elname) 176 177 #define EXT4_RO_ATTR_ES_STRING(_name,_elname,_size) \ 178 EXT4_ATTR_STRING(_name, 0444, _size, ext4_super_block, _elname) 179 180 #define EXT4_RW_ATTR_SBI_UI(_name,_elname) \ 181 EXT4_ATTR_OFFSET(_name, 0644, pointer_ui, ext4_sb_info, _elname) 182 183 #define EXT4_RW_ATTR_SBI_UL(_name,_elname) \ 184 EXT4_ATTR_OFFSET(_name, 0644, pointer_ul, ext4_sb_info, _elname) 185 186 #define EXT4_RO_ATTR_SBI_ATOMIC(_name,_elname) \ 187 EXT4_ATTR_OFFSET(_name, 0444, pointer_atomic, ext4_sb_info, _elname) 188 189 #define EXT4_ATTR_PTR(_name,_mode,_id,_ptr) \ 190 static struct ext4_attr ext4_attr_##_name = { \ 191 .attr = {.name = __stringify(_name), .mode = _mode }, \ 192 .attr_id = attr_##_id, \ 193 .attr_ptr = ptr_explicit, \ 194 .u = { \ 195 .explicit_ptr = _ptr, \ 196 }, \ 197 } 198 199 #define ATTR_LIST(name) &ext4_attr_##name.attr 200 201 EXT4_ATTR_FUNC(delayed_allocation_blocks, 0444); 202 EXT4_ATTR_FUNC(session_write_kbytes, 0444); 203 EXT4_ATTR_FUNC(lifetime_write_kbytes, 0444); 204 EXT4_ATTR_FUNC(reserved_clusters, 0644); 205 206 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, inode_readahead, 207 ext4_sb_info, s_inode_readahead_blks); 208 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal); 209 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats); 210 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan); 211 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan); 212 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs); 213 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request); 214 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc); 215 EXT4_RW_ATTR_SBI_UI(mb_max_inode_prealloc, s_mb_max_inode_prealloc); 216 EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb); 217 EXT4_ATTR(trigger_fs_error, 0200, trigger_test_error); 218 EXT4_RW_ATTR_SBI_UI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval); 219 EXT4_RW_ATTR_SBI_UI(err_ratelimit_burst, s_err_ratelimit_state.burst); 220 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval); 221 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_burst, s_warning_ratelimit_state.burst); 222 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval); 223 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_burst, s_msg_ratelimit_state.burst); 224 #ifdef CONFIG_EXT4_DEBUG 225 EXT4_RW_ATTR_SBI_UL(simulate_fail, s_simulate_fail); 226 #endif 227 EXT4_RO_ATTR_SBI_ATOMIC(warning_count, s_warning_count); 228 EXT4_RO_ATTR_SBI_ATOMIC(msg_count, s_msg_count); 229 EXT4_RO_ATTR_ES_UI(errors_count, s_error_count); 230 EXT4_RO_ATTR_ES_U8(first_error_errcode, s_first_error_errcode); 231 EXT4_RO_ATTR_ES_U8(last_error_errcode, s_last_error_errcode); 232 EXT4_RO_ATTR_ES_UI(first_error_ino, s_first_error_ino); 233 EXT4_RO_ATTR_ES_UI(last_error_ino, s_last_error_ino); 234 EXT4_RO_ATTR_ES_U64(first_error_block, s_first_error_block); 235 EXT4_RO_ATTR_ES_U64(last_error_block, s_last_error_block); 236 EXT4_RO_ATTR_ES_UI(first_error_line, s_first_error_line); 237 EXT4_RO_ATTR_ES_UI(last_error_line, s_last_error_line); 238 EXT4_RO_ATTR_ES_STRING(first_error_func, s_first_error_func, 32); 239 EXT4_RO_ATTR_ES_STRING(last_error_func, s_last_error_func, 32); 240 EXT4_ATTR(first_error_time, 0444, first_error_time); 241 EXT4_ATTR(last_error_time, 0444, last_error_time); 242 EXT4_ATTR(journal_task, 0444, journal_task); 243 EXT4_RW_ATTR_SBI_UI(mb_prefetch, s_mb_prefetch); 244 EXT4_RW_ATTR_SBI_UI(mb_prefetch_limit, s_mb_prefetch_limit); 245 246 static unsigned int old_bump_val = 128; 247 EXT4_ATTR_PTR(max_writeback_mb_bump, 0444, pointer_ui, &old_bump_val); 248 249 static struct attribute *ext4_attrs[] = { 250 ATTR_LIST(delayed_allocation_blocks), 251 ATTR_LIST(session_write_kbytes), 252 ATTR_LIST(lifetime_write_kbytes), 253 ATTR_LIST(reserved_clusters), 254 ATTR_LIST(inode_readahead_blks), 255 ATTR_LIST(inode_goal), 256 ATTR_LIST(mb_stats), 257 ATTR_LIST(mb_max_to_scan), 258 ATTR_LIST(mb_min_to_scan), 259 ATTR_LIST(mb_order2_req), 260 ATTR_LIST(mb_stream_req), 261 ATTR_LIST(mb_group_prealloc), 262 ATTR_LIST(mb_max_inode_prealloc), 263 ATTR_LIST(max_writeback_mb_bump), 264 ATTR_LIST(extent_max_zeroout_kb), 265 ATTR_LIST(trigger_fs_error), 266 ATTR_LIST(err_ratelimit_interval_ms), 267 ATTR_LIST(err_ratelimit_burst), 268 ATTR_LIST(warning_ratelimit_interval_ms), 269 ATTR_LIST(warning_ratelimit_burst), 270 ATTR_LIST(msg_ratelimit_interval_ms), 271 ATTR_LIST(msg_ratelimit_burst), 272 ATTR_LIST(errors_count), 273 ATTR_LIST(warning_count), 274 ATTR_LIST(msg_count), 275 ATTR_LIST(first_error_ino), 276 ATTR_LIST(last_error_ino), 277 ATTR_LIST(first_error_block), 278 ATTR_LIST(last_error_block), 279 ATTR_LIST(first_error_line), 280 ATTR_LIST(last_error_line), 281 ATTR_LIST(first_error_func), 282 ATTR_LIST(last_error_func), 283 ATTR_LIST(first_error_errcode), 284 ATTR_LIST(last_error_errcode), 285 ATTR_LIST(first_error_time), 286 ATTR_LIST(last_error_time), 287 ATTR_LIST(journal_task), 288 #ifdef CONFIG_EXT4_DEBUG 289 ATTR_LIST(simulate_fail), 290 #endif 291 ATTR_LIST(mb_prefetch), 292 ATTR_LIST(mb_prefetch_limit), 293 NULL, 294 }; 295 ATTRIBUTE_GROUPS(ext4); 296 297 /* Features this copy of ext4 supports */ 298 EXT4_ATTR_FEATURE(lazy_itable_init); 299 EXT4_ATTR_FEATURE(batched_discard); 300 EXT4_ATTR_FEATURE(meta_bg_resize); 301 #ifdef CONFIG_FS_ENCRYPTION 302 EXT4_ATTR_FEATURE(encryption); 303 EXT4_ATTR_FEATURE(test_dummy_encryption_v2); 304 #endif 305 #ifdef CONFIG_UNICODE 306 EXT4_ATTR_FEATURE(casefold); 307 #endif 308 #ifdef CONFIG_FS_VERITY 309 EXT4_ATTR_FEATURE(verity); 310 #endif 311 EXT4_ATTR_FEATURE(metadata_csum_seed); 312 EXT4_ATTR_FEATURE(fast_commit); 313 314 static struct attribute *ext4_feat_attrs[] = { 315 ATTR_LIST(lazy_itable_init), 316 ATTR_LIST(batched_discard), 317 ATTR_LIST(meta_bg_resize), 318 #ifdef CONFIG_FS_ENCRYPTION 319 ATTR_LIST(encryption), 320 ATTR_LIST(test_dummy_encryption_v2), 321 #endif 322 #ifdef CONFIG_UNICODE 323 ATTR_LIST(casefold), 324 #endif 325 #ifdef CONFIG_FS_VERITY 326 ATTR_LIST(verity), 327 #endif 328 ATTR_LIST(metadata_csum_seed), 329 ATTR_LIST(fast_commit), 330 NULL, 331 }; 332 ATTRIBUTE_GROUPS(ext4_feat); 333 334 static void *calc_ptr(struct ext4_attr *a, struct ext4_sb_info *sbi) 335 { 336 switch (a->attr_ptr) { 337 case ptr_explicit: 338 return a->u.explicit_ptr; 339 case ptr_ext4_sb_info_offset: 340 return (void *) (((char *) sbi) + a->u.offset); 341 case ptr_ext4_super_block_offset: 342 return (void *) (((char *) sbi->s_es) + a->u.offset); 343 } 344 return NULL; 345 } 346 347 static ssize_t __print_tstamp(char *buf, __le32 lo, __u8 hi) 348 { 349 return snprintf(buf, PAGE_SIZE, "%lld\n", 350 ((time64_t)hi << 32) + le32_to_cpu(lo)); 351 } 352 353 #define print_tstamp(buf, es, tstamp) \ 354 __print_tstamp(buf, (es)->tstamp, (es)->tstamp ## _hi) 355 356 static ssize_t ext4_attr_show(struct kobject *kobj, 357 struct attribute *attr, char *buf) 358 { 359 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info, 360 s_kobj); 361 struct ext4_attr *a = container_of(attr, struct ext4_attr, attr); 362 void *ptr = calc_ptr(a, sbi); 363 364 switch (a->attr_id) { 365 case attr_delayed_allocation_blocks: 366 return snprintf(buf, PAGE_SIZE, "%llu\n", 367 (s64) EXT4_C2B(sbi, 368 percpu_counter_sum(&sbi->s_dirtyclusters_counter))); 369 case attr_session_write_kbytes: 370 return session_write_kbytes_show(sbi, buf); 371 case attr_lifetime_write_kbytes: 372 return lifetime_write_kbytes_show(sbi, buf); 373 case attr_reserved_clusters: 374 return snprintf(buf, PAGE_SIZE, "%llu\n", 375 (unsigned long long) 376 atomic64_read(&sbi->s_resv_clusters)); 377 case attr_inode_readahead: 378 case attr_pointer_ui: 379 if (!ptr) 380 return 0; 381 if (a->attr_ptr == ptr_ext4_super_block_offset) 382 return snprintf(buf, PAGE_SIZE, "%u\n", 383 le32_to_cpup(ptr)); 384 else 385 return snprintf(buf, PAGE_SIZE, "%u\n", 386 *((unsigned int *) ptr)); 387 case attr_pointer_ul: 388 if (!ptr) 389 return 0; 390 return snprintf(buf, PAGE_SIZE, "%lu\n", 391 *((unsigned long *) ptr)); 392 case attr_pointer_u8: 393 if (!ptr) 394 return 0; 395 return snprintf(buf, PAGE_SIZE, "%u\n", 396 *((unsigned char *) ptr)); 397 case attr_pointer_u64: 398 if (!ptr) 399 return 0; 400 if (a->attr_ptr == ptr_ext4_super_block_offset) 401 return snprintf(buf, PAGE_SIZE, "%llu\n", 402 le64_to_cpup(ptr)); 403 else 404 return snprintf(buf, PAGE_SIZE, "%llu\n", 405 *((unsigned long long *) ptr)); 406 case attr_pointer_string: 407 if (!ptr) 408 return 0; 409 return snprintf(buf, PAGE_SIZE, "%.*s\n", a->attr_size, 410 (char *) ptr); 411 case attr_pointer_atomic: 412 if (!ptr) 413 return 0; 414 return snprintf(buf, PAGE_SIZE, "%d\n", 415 atomic_read((atomic_t *) ptr)); 416 case attr_feature: 417 return snprintf(buf, PAGE_SIZE, "supported\n"); 418 case attr_first_error_time: 419 return print_tstamp(buf, sbi->s_es, s_first_error_time); 420 case attr_last_error_time: 421 return print_tstamp(buf, sbi->s_es, s_last_error_time); 422 case attr_journal_task: 423 return journal_task_show(sbi, buf); 424 } 425 426 return 0; 427 } 428 429 static ssize_t ext4_attr_store(struct kobject *kobj, 430 struct attribute *attr, 431 const char *buf, size_t len) 432 { 433 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info, 434 s_kobj); 435 struct ext4_attr *a = container_of(attr, struct ext4_attr, attr); 436 void *ptr = calc_ptr(a, sbi); 437 unsigned long t; 438 int ret; 439 440 switch (a->attr_id) { 441 case attr_reserved_clusters: 442 return reserved_clusters_store(sbi, buf, len); 443 case attr_pointer_ui: 444 if (!ptr) 445 return 0; 446 ret = kstrtoul(skip_spaces(buf), 0, &t); 447 if (ret) 448 return ret; 449 if (a->attr_ptr == ptr_ext4_super_block_offset) 450 *((__le32 *) ptr) = cpu_to_le32(t); 451 else 452 *((unsigned int *) ptr) = t; 453 return len; 454 case attr_pointer_ul: 455 if (!ptr) 456 return 0; 457 ret = kstrtoul(skip_spaces(buf), 0, &t); 458 if (ret) 459 return ret; 460 *((unsigned long *) ptr) = t; 461 return len; 462 case attr_inode_readahead: 463 return inode_readahead_blks_store(sbi, buf, len); 464 case attr_trigger_test_error: 465 return trigger_test_error(sbi, buf, len); 466 } 467 return 0; 468 } 469 470 static void ext4_sb_release(struct kobject *kobj) 471 { 472 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info, 473 s_kobj); 474 complete(&sbi->s_kobj_unregister); 475 } 476 477 static const struct sysfs_ops ext4_attr_ops = { 478 .show = ext4_attr_show, 479 .store = ext4_attr_store, 480 }; 481 482 static struct kobj_type ext4_sb_ktype = { 483 .default_groups = ext4_groups, 484 .sysfs_ops = &ext4_attr_ops, 485 .release = ext4_sb_release, 486 }; 487 488 static struct kobj_type ext4_feat_ktype = { 489 .default_groups = ext4_feat_groups, 490 .sysfs_ops = &ext4_attr_ops, 491 .release = (void (*)(struct kobject *))kfree, 492 }; 493 494 static struct kobject *ext4_root; 495 496 static struct kobject *ext4_feat; 497 498 int ext4_register_sysfs(struct super_block *sb) 499 { 500 struct ext4_sb_info *sbi = EXT4_SB(sb); 501 int err; 502 503 init_completion(&sbi->s_kobj_unregister); 504 err = kobject_init_and_add(&sbi->s_kobj, &ext4_sb_ktype, ext4_root, 505 "%s", sb->s_id); 506 if (err) { 507 kobject_put(&sbi->s_kobj); 508 wait_for_completion(&sbi->s_kobj_unregister); 509 return err; 510 } 511 512 if (ext4_proc_root) 513 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root); 514 if (sbi->s_proc) { 515 proc_create_single_data("options", S_IRUGO, sbi->s_proc, 516 ext4_seq_options_show, sb); 517 proc_create_single_data("es_shrinker_info", S_IRUGO, 518 sbi->s_proc, ext4_seq_es_shrinker_info_show, 519 sb); 520 proc_create_single_data("fc_info", 0444, sbi->s_proc, 521 ext4_fc_info_show, sb); 522 proc_create_seq_data("mb_groups", S_IRUGO, sbi->s_proc, 523 &ext4_mb_seq_groups_ops, sb); 524 } 525 return 0; 526 } 527 528 void ext4_unregister_sysfs(struct super_block *sb) 529 { 530 struct ext4_sb_info *sbi = EXT4_SB(sb); 531 532 if (sbi->s_proc) 533 remove_proc_subtree(sb->s_id, ext4_proc_root); 534 kobject_del(&sbi->s_kobj); 535 } 536 537 int __init ext4_init_sysfs(void) 538 { 539 int ret; 540 541 ext4_root = kobject_create_and_add("ext4", fs_kobj); 542 if (!ext4_root) 543 return -ENOMEM; 544 545 ext4_feat = kzalloc(sizeof(*ext4_feat), GFP_KERNEL); 546 if (!ext4_feat) { 547 ret = -ENOMEM; 548 goto root_err; 549 } 550 551 ret = kobject_init_and_add(ext4_feat, &ext4_feat_ktype, 552 ext4_root, "features"); 553 if (ret) 554 goto feat_err; 555 556 ext4_proc_root = proc_mkdir(proc_dirname, NULL); 557 return ret; 558 559 feat_err: 560 kobject_put(ext4_feat); 561 ext4_feat = NULL; 562 root_err: 563 kobject_put(ext4_root); 564 ext4_root = NULL; 565 return ret; 566 } 567 568 void ext4_exit_sysfs(void) 569 { 570 kobject_put(ext4_feat); 571 ext4_feat = NULL; 572 kobject_put(ext4_root); 573 ext4_root = NULL; 574 remove_proc_entry(proc_dirname, NULL); 575 ext4_proc_root = NULL; 576 } 577 578