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