fs/ext4/sysfs.c

   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_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
  45 typedef enum {
  46         ptr_explicit,
  47         ptr_ext4_sb_info_offset,
  48         ptr_ext4_super_block_offset,
  49 } attr_ptr_t;
  50
  51 static const char proc_dirname[] = "fs/ext4";
  52 static struct proc_dir_entry *ext4_proc_root;
  53
  54 struct 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
  65 static 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
  74 static 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
  84 static 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
 101 static 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
 117 static 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
 133 static 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)                                      \
 142 static 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)       \
 152 static 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)     \
 162 static 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) \
 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,                               \
 201         .u = {                                                  \
 202                 .explicit_ptr = _ptr,                           \
 203         },                                                      \
 204 }
 205
 206 #define ATTR_LIST(name) &ext4_attr_##name.attr
 207
 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);
 213
 214 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, inode_readahead,
 215                  ext4_sb_info, s_inode_readahead_blks);
 216 EXT4_ATTR_OFFSET(mb_group_prealloc, 0644, clusters_in_group,
 217                  ext4_sb_info, s_mb_group_prealloc);
 218 EXT4_ATTR_OFFSET(mb_best_avail_max_trim_order, 0644, mb_order,
 219                  ext4_sb_info, s_mb_best_avail_max_trim_order);
 220 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
 221 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
 222 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
 223 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
 224 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
 225 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
 226 EXT4_RW_ATTR_SBI_UI(mb_max_linear_groups, s_mb_max_linear_groups);
 227 EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb);
 228 EXT4_ATTR(trigger_fs_error, 0200, trigger_test_error);
 229 EXT4_RW_ATTR_SBI_PI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval);
 230 EXT4_RW_ATTR_SBI_PI(err_ratelimit_burst, s_err_ratelimit_state.burst);
 231 EXT4_RW_ATTR_SBI_PI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval);
 232 EXT4_RW_ATTR_SBI_PI(warning_ratelimit_burst, s_warning_ratelimit_state.burst);
 233 EXT4_RW_ATTR_SBI_PI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval);
 234 EXT4_RW_ATTR_SBI_PI(msg_ratelimit_burst, s_msg_ratelimit_state.burst);
 235 #ifdef CONFIG_EXT4_DEBUG
 236 EXT4_RW_ATTR_SBI_UL(simulate_fail, s_simulate_fail);
 237 #endif
 238 EXT4_RO_ATTR_SBI_ATOMIC(warning_count, s_warning_count);
 239 EXT4_RO_ATTR_SBI_ATOMIC(msg_count, s_msg_count);
 240 EXT4_RO_ATTR_ES_UI(errors_count, s_error_count);
 241 EXT4_RO_ATTR_ES_U8(first_error_errcode, s_first_error_errcode);
 242 EXT4_RO_ATTR_ES_U8(last_error_errcode, s_last_error_errcode);
 243 EXT4_RO_ATTR_ES_UI(first_error_ino, s_first_error_ino);
 244 EXT4_RO_ATTR_ES_UI(last_error_ino, s_last_error_ino);
 245 EXT4_RO_ATTR_ES_U64(first_error_block, s_first_error_block);
 246 EXT4_RO_ATTR_ES_U64(last_error_block, s_last_error_block);
 247 EXT4_RO_ATTR_ES_UI(first_error_line, s_first_error_line);
 248 EXT4_RO_ATTR_ES_UI(last_error_line, s_last_error_line);
 249 EXT4_RO_ATTR_ES_STRING(first_error_func, s_first_error_func, 32);
 250 EXT4_RO_ATTR_ES_STRING(last_error_func, s_last_error_func, 32);
 251 EXT4_ATTR(first_error_time, 0444, first_error_time);
 252 EXT4_ATTR(last_error_time, 0444, last_error_time);
 253 EXT4_ATTR(journal_task, 0444, journal_task);
 254 EXT4_RW_ATTR_SBI_UI(mb_prefetch, s_mb_prefetch);
 255 EXT4_RW_ATTR_SBI_UI(mb_prefetch_limit, s_mb_prefetch_limit);
 256 EXT4_RW_ATTR_SBI_UL(last_trim_minblks, s_last_trim_minblks);
 257
 258 static unsigned int old_bump_val = 128;
 259 EXT4_ATTR_PTR(max_writeback_mb_bump, 0444, pointer_ui, &old_bump_val);
 260
 261 static 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_DEBUG
 303         ATTR_LIST(simulate_fail),
 304 #endif
 305         ATTR_LIST(mb_prefetch),
 306         ATTR_LIST(mb_prefetch_limit),
 307         ATTR_LIST(last_trim_minblks),
 308         NULL,
 309 };
 310 ATTRIBUTE_GROUPS(ext4);
 311
 312 /* Features this copy of ext4 supports */
 313 EXT4_ATTR_FEATURE(lazy_itable_init);
 314 EXT4_ATTR_FEATURE(batched_discard);
 315 EXT4_ATTR_FEATURE(meta_bg_resize);
 316 #ifdef CONFIG_FS_ENCRYPTION
 317 EXT4_ATTR_FEATURE(encryption);
 318 EXT4_ATTR_FEATURE(test_dummy_encryption_v2);
 319 #endif
 320 #if IS_ENABLED(CONFIG_UNICODE)
 321 EXT4_ATTR_FEATURE(casefold);
 322 #endif
 323 #ifdef CONFIG_FS_VERITY
 324 EXT4_ATTR_FEATURE(verity);
 325 #endif
 326 EXT4_ATTR_FEATURE(metadata_csum_seed);
 327 EXT4_ATTR_FEATURE(fast_commit);
 328 #if IS_ENABLED(CONFIG_UNICODE) && defined(CONFIG_FS_ENCRYPTION)
 329 EXT4_ATTR_FEATURE(encrypted_casefold);
 330 #endif
 331
 332 static 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_ENCRYPTION
 337         ATTR_LIST(encryption),
 338         ATTR_LIST(test_dummy_encryption_v2),
 339 #endif
 340 #if IS_ENABLED(CONFIG_UNICODE)
 341         ATTR_LIST(casefold),
 342 #endif
 343 #ifdef CONFIG_FS_VERITY
 344         ATTR_LIST(verity),
 345 #endif
 346         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 #endif
 351         NULL,
 352 };
 353 ATTRIBUTE_GROUPS(ext4_feat);
 354
 355 static 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
 368 static 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
 377 static 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
 410 static 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
 447 static 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                 else
 475                         *((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, &lt);
 495                 if (ret)
 496                         return ret;
 497                 *((unsigned long *) ptr) = lt;
 498                 return len;
 499         }
 500         return 0;
 501 }
 502
 503 static 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
 523 static 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
 530 static void ext4_feat_release(struct kobject *kobj)
 531 {
 532         kfree(kobj);
 533 }
 534
 535 static const struct sysfs_ops ext4_attr_ops = {
 536         .show   = ext4_attr_show,
 537         .store  = ext4_attr_store,
 538 };
 539
 540 static 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
 546 static 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
 552 void ext4_notify_error_sysfs(struct ext4_sb_info *sbi)
 553 {
 554         sysfs_notify(&sbi->s_kobj, NULL, "errors_count");
 555 }
 556
 557 static struct kobject *ext4_root;
 558
 559 static struct kobject *ext4_feat;
 560
 561 int 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
 595 void 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
 604 int __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
 626 feat_err:
 627         kobject_put(ext4_feat);
 628         ext4_feat = NULL;
 629 root_err:
 630         kobject_put(ext4_root);
 631         ext4_root = NULL;
 632         return ret;
 633 }
 634
 635 void 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