1 /* 2 * linux/fs/ext4/sysfs.c 3 * 4 * Copyright (C) 1992, 1993, 1994, 1995 5 * Remy Card (card@masi.ibp.fr) 6 * Theodore Ts'o (tytso@mit.edu) 7 * 8 */ 9 10 #include <linux/time.h> 11 #include <linux/fs.h> 12 #include <linux/seq_file.h> 13 #include <linux/proc_fs.h> 14 15 #include "ext4.h" 16 #include "ext4_jbd2.h" 17 18 typedef enum { 19 attr_noop, 20 attr_delayed_allocation_blocks, 21 attr_session_write_kbytes, 22 attr_lifetime_write_kbytes, 23 attr_reserved_clusters, 24 attr_inode_readahead, 25 attr_trigger_test_error, 26 attr_feature, 27 attr_pointer_ui, 28 attr_pointer_atomic, 29 } attr_id_t; 30 31 typedef enum { 32 ptr_explicit, 33 ptr_ext4_sb_info_offset, 34 ptr_ext4_super_block_offset, 35 } attr_ptr_t; 36 37 static const char proc_dirname[] = "fs/ext4"; 38 static struct proc_dir_entry *ext4_proc_root; 39 40 struct ext4_attr { 41 struct attribute attr; 42 short attr_id; 43 short attr_ptr; 44 union { 45 int offset; 46 void *explicit_ptr; 47 } u; 48 }; 49 50 static ssize_t session_write_kbytes_show(struct ext4_attr *a, 51 struct ext4_sb_info *sbi, char *buf) 52 { 53 struct super_block *sb = sbi->s_buddy_cache->i_sb; 54 55 if (!sb->s_bdev->bd_part) 56 return snprintf(buf, PAGE_SIZE, "0\n"); 57 return snprintf(buf, PAGE_SIZE, "%lu\n", 58 (part_stat_read(sb->s_bdev->bd_part, sectors[1]) - 59 sbi->s_sectors_written_start) >> 1); 60 } 61 62 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a, 63 struct ext4_sb_info *sbi, char *buf) 64 { 65 struct super_block *sb = sbi->s_buddy_cache->i_sb; 66 67 if (!sb->s_bdev->bd_part) 68 return snprintf(buf, PAGE_SIZE, "0\n"); 69 return snprintf(buf, PAGE_SIZE, "%llu\n", 70 (unsigned long long)(sbi->s_kbytes_written + 71 ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) - 72 EXT4_SB(sb)->s_sectors_written_start) >> 1))); 73 } 74 75 static ssize_t inode_readahead_blks_store(struct ext4_attr *a, 76 struct ext4_sb_info *sbi, 77 const char *buf, size_t count) 78 { 79 unsigned long t; 80 int ret; 81 82 ret = kstrtoul(skip_spaces(buf), 0, &t); 83 if (ret) 84 return ret; 85 86 if (t && (!is_power_of_2(t) || t > 0x40000000)) 87 return -EINVAL; 88 89 sbi->s_inode_readahead_blks = t; 90 return count; 91 } 92 93 static ssize_t reserved_clusters_store(struct ext4_attr *a, 94 struct ext4_sb_info *sbi, 95 const char *buf, size_t count) 96 { 97 unsigned long long val; 98 ext4_fsblk_t clusters = (ext4_blocks_count(sbi->s_es) >> 99 sbi->s_cluster_bits); 100 int ret; 101 102 ret = kstrtoull(skip_spaces(buf), 0, &val); 103 if (!ret || val >= clusters) 104 return -EINVAL; 105 106 atomic64_set(&sbi->s_resv_clusters, val); 107 return count; 108 } 109 110 static ssize_t trigger_test_error(struct ext4_attr *a, 111 struct ext4_sb_info *sbi, 112 const char *buf, size_t count) 113 { 114 int len = count; 115 116 if (!capable(CAP_SYS_ADMIN)) 117 return -EPERM; 118 119 if (len && buf[len-1] == '\n') 120 len--; 121 122 if (len) 123 ext4_error(sbi->s_sb, "%.*s", len, buf); 124 return count; 125 } 126 127 #define EXT4_ATTR(_name,_mode,_id) \ 128 static struct ext4_attr ext4_attr_##_name = { \ 129 .attr = {.name = __stringify(_name), .mode = _mode }, \ 130 .attr_id = attr_##_id, \ 131 } 132 133 #define EXT4_ATTR_FUNC(_name,_mode) EXT4_ATTR(_name,_mode,_name) 134 135 #define EXT4_ATTR_FEATURE(_name) EXT4_ATTR(_name, 0444, feature) 136 137 #define EXT4_ATTR_OFFSET(_name,_mode,_id,_struct,_elname) \ 138 static struct ext4_attr ext4_attr_##_name = { \ 139 .attr = {.name = __stringify(_name), .mode = _mode }, \ 140 .attr_id = attr_##_id, \ 141 .attr_ptr = ptr_##_struct##_offset, \ 142 .u = { \ 143 .offset = offsetof(struct _struct, _elname),\ 144 }, \ 145 } 146 147 #define EXT4_RO_ATTR_ES_UI(_name,_elname) \ 148 EXT4_ATTR_OFFSET(_name, 0444, pointer_ui, ext4_super_block, _elname) 149 150 #define EXT4_RW_ATTR_SBI_UI(_name,_elname) \ 151 EXT4_ATTR_OFFSET(_name, 0644, pointer_ui, ext4_sb_info, _elname) 152 153 #define EXT4_ATTR_PTR(_name,_mode,_id,_ptr) \ 154 static struct ext4_attr ext4_attr_##_name = { \ 155 .attr = {.name = __stringify(_name), .mode = _mode }, \ 156 .attr_id = attr_##_id, \ 157 .attr_ptr = ptr_explicit, \ 158 .u = { \ 159 .explicit_ptr = _ptr, \ 160 }, \ 161 } 162 163 #define ATTR_LIST(name) &ext4_attr_##name.attr 164 165 EXT4_ATTR_FUNC(delayed_allocation_blocks, 0444); 166 EXT4_ATTR_FUNC(session_write_kbytes, 0444); 167 EXT4_ATTR_FUNC(lifetime_write_kbytes, 0444); 168 EXT4_ATTR_FUNC(reserved_clusters, 0644); 169 170 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, inode_readahead, 171 ext4_sb_info, s_inode_readahead_blks); 172 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal); 173 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats); 174 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan); 175 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan); 176 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs); 177 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request); 178 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc); 179 EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb); 180 EXT4_ATTR(trigger_fs_error, 0200, trigger_test_error); 181 EXT4_RW_ATTR_SBI_UI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval); 182 EXT4_RW_ATTR_SBI_UI(err_ratelimit_burst, s_err_ratelimit_state.burst); 183 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval); 184 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_burst, s_warning_ratelimit_state.burst); 185 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval); 186 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_burst, s_msg_ratelimit_state.burst); 187 EXT4_RO_ATTR_ES_UI(errors_count, s_error_count); 188 EXT4_RO_ATTR_ES_UI(first_error_time, s_first_error_time); 189 EXT4_RO_ATTR_ES_UI(last_error_time, s_last_error_time); 190 191 static unsigned int old_bump_val = 128; 192 EXT4_ATTR_PTR(max_writeback_mb_bump, 0444, pointer_ui, &old_bump_val); 193 194 static struct attribute *ext4_attrs[] = { 195 ATTR_LIST(delayed_allocation_blocks), 196 ATTR_LIST(session_write_kbytes), 197 ATTR_LIST(lifetime_write_kbytes), 198 ATTR_LIST(reserved_clusters), 199 ATTR_LIST(inode_readahead_blks), 200 ATTR_LIST(inode_goal), 201 ATTR_LIST(mb_stats), 202 ATTR_LIST(mb_max_to_scan), 203 ATTR_LIST(mb_min_to_scan), 204 ATTR_LIST(mb_order2_req), 205 ATTR_LIST(mb_stream_req), 206 ATTR_LIST(mb_group_prealloc), 207 ATTR_LIST(max_writeback_mb_bump), 208 ATTR_LIST(extent_max_zeroout_kb), 209 ATTR_LIST(trigger_fs_error), 210 ATTR_LIST(err_ratelimit_interval_ms), 211 ATTR_LIST(err_ratelimit_burst), 212 ATTR_LIST(warning_ratelimit_interval_ms), 213 ATTR_LIST(warning_ratelimit_burst), 214 ATTR_LIST(msg_ratelimit_interval_ms), 215 ATTR_LIST(msg_ratelimit_burst), 216 ATTR_LIST(errors_count), 217 ATTR_LIST(first_error_time), 218 ATTR_LIST(last_error_time), 219 NULL, 220 }; 221 222 /* Features this copy of ext4 supports */ 223 EXT4_ATTR_FEATURE(lazy_itable_init); 224 EXT4_ATTR_FEATURE(batched_discard); 225 EXT4_ATTR_FEATURE(meta_bg_resize); 226 #ifdef CONFIG_EXT4_FS_ENCRYPTION 227 EXT4_ATTR_FEATURE(encryption); 228 #endif 229 EXT4_ATTR_FEATURE(metadata_csum_seed); 230 231 static struct attribute *ext4_feat_attrs[] = { 232 ATTR_LIST(lazy_itable_init), 233 ATTR_LIST(batched_discard), 234 ATTR_LIST(meta_bg_resize), 235 #ifdef CONFIG_EXT4_FS_ENCRYPTION 236 ATTR_LIST(encryption), 237 #endif 238 ATTR_LIST(metadata_csum_seed), 239 NULL, 240 }; 241 242 static void *calc_ptr(struct ext4_attr *a, struct ext4_sb_info *sbi) 243 { 244 switch (a->attr_ptr) { 245 case ptr_explicit: 246 return a->u.explicit_ptr; 247 case ptr_ext4_sb_info_offset: 248 return (void *) (((char *) sbi) + a->u.offset); 249 case ptr_ext4_super_block_offset: 250 return (void *) (((char *) sbi->s_es) + a->u.offset); 251 } 252 return NULL; 253 } 254 255 static ssize_t ext4_attr_show(struct kobject *kobj, 256 struct attribute *attr, char *buf) 257 { 258 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info, 259 s_kobj); 260 struct ext4_attr *a = container_of(attr, struct ext4_attr, attr); 261 void *ptr = calc_ptr(a, sbi); 262 263 switch (a->attr_id) { 264 case attr_delayed_allocation_blocks: 265 return snprintf(buf, PAGE_SIZE, "%llu\n", 266 (s64) EXT4_C2B(sbi, 267 percpu_counter_sum(&sbi->s_dirtyclusters_counter))); 268 case attr_session_write_kbytes: 269 return session_write_kbytes_show(a, sbi, buf); 270 case attr_lifetime_write_kbytes: 271 return lifetime_write_kbytes_show(a, sbi, buf); 272 case attr_reserved_clusters: 273 return snprintf(buf, PAGE_SIZE, "%llu\n", 274 (unsigned long long) 275 atomic64_read(&sbi->s_resv_clusters)); 276 case attr_inode_readahead: 277 case attr_pointer_ui: 278 if (!ptr) 279 return 0; 280 return snprintf(buf, PAGE_SIZE, "%u\n", 281 *((unsigned int *) ptr)); 282 case attr_pointer_atomic: 283 if (!ptr) 284 return 0; 285 return snprintf(buf, PAGE_SIZE, "%d\n", 286 atomic_read((atomic_t *) ptr)); 287 case attr_feature: 288 return snprintf(buf, PAGE_SIZE, "supported\n"); 289 } 290 291 return 0; 292 } 293 294 static ssize_t ext4_attr_store(struct kobject *kobj, 295 struct attribute *attr, 296 const char *buf, size_t len) 297 { 298 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info, 299 s_kobj); 300 struct ext4_attr *a = container_of(attr, struct ext4_attr, attr); 301 void *ptr = calc_ptr(a, sbi); 302 unsigned long t; 303 int ret; 304 305 switch (a->attr_id) { 306 case attr_reserved_clusters: 307 return reserved_clusters_store(a, sbi, buf, len); 308 case attr_pointer_ui: 309 if (!ptr) 310 return 0; 311 ret = kstrtoul(skip_spaces(buf), 0, &t); 312 if (ret) 313 return ret; 314 *((unsigned int *) ptr) = t; 315 return len; 316 case attr_inode_readahead: 317 return inode_readahead_blks_store(a, sbi, buf, len); 318 case attr_trigger_test_error: 319 return trigger_test_error(a, sbi, buf, len); 320 } 321 return 0; 322 } 323 324 static void ext4_sb_release(struct kobject *kobj) 325 { 326 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info, 327 s_kobj); 328 complete(&sbi->s_kobj_unregister); 329 } 330 331 static const struct sysfs_ops ext4_attr_ops = { 332 .show = ext4_attr_show, 333 .store = ext4_attr_store, 334 }; 335 336 static struct kobj_type ext4_sb_ktype = { 337 .default_attrs = ext4_attrs, 338 .sysfs_ops = &ext4_attr_ops, 339 .release = ext4_sb_release, 340 }; 341 342 static struct kobj_type ext4_ktype = { 343 .sysfs_ops = &ext4_attr_ops, 344 }; 345 346 static struct kset ext4_kset = { 347 .kobj = {.ktype = &ext4_ktype}, 348 }; 349 350 static struct kobj_type ext4_feat_ktype = { 351 .default_attrs = ext4_feat_attrs, 352 .sysfs_ops = &ext4_attr_ops, 353 }; 354 355 static struct kobject ext4_feat = { 356 .kset = &ext4_kset, 357 }; 358 359 #define PROC_FILE_SHOW_DEFN(name) \ 360 static int name##_open(struct inode *inode, struct file *file) \ 361 { \ 362 return single_open(file, ext4_seq_##name##_show, PDE_DATA(inode)); \ 363 } \ 364 \ 365 static const struct file_operations ext4_seq_##name##_fops = { \ 366 .open = name##_open, \ 367 .read = seq_read, \ 368 .llseek = seq_lseek, \ 369 .release = single_release, \ 370 } 371 372 #define PROC_FILE_LIST(name) \ 373 { __stringify(name), &ext4_seq_##name##_fops } 374 375 PROC_FILE_SHOW_DEFN(es_shrinker_info); 376 PROC_FILE_SHOW_DEFN(options); 377 378 static const struct ext4_proc_files { 379 const char *name; 380 const struct file_operations *fops; 381 } proc_files[] = { 382 PROC_FILE_LIST(options), 383 PROC_FILE_LIST(es_shrinker_info), 384 PROC_FILE_LIST(mb_groups), 385 { NULL, NULL }, 386 }; 387 388 int ext4_register_sysfs(struct super_block *sb) 389 { 390 struct ext4_sb_info *sbi = EXT4_SB(sb); 391 const struct ext4_proc_files *p; 392 int err; 393 394 sbi->s_kobj.kset = &ext4_kset; 395 init_completion(&sbi->s_kobj_unregister); 396 err = kobject_init_and_add(&sbi->s_kobj, &ext4_sb_ktype, NULL, 397 "%s", sb->s_id); 398 if (err) 399 return err; 400 401 if (ext4_proc_root) 402 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root); 403 404 if (sbi->s_proc) { 405 for (p = proc_files; p->name; p++) 406 proc_create_data(p->name, S_IRUGO, sbi->s_proc, 407 p->fops, sb); 408 } 409 return 0; 410 } 411 412 void ext4_unregister_sysfs(struct super_block *sb) 413 { 414 struct ext4_sb_info *sbi = EXT4_SB(sb); 415 const struct ext4_proc_files *p; 416 417 if (sbi->s_proc) { 418 for (p = proc_files; p->name; p++) 419 remove_proc_entry(p->name, sbi->s_proc); 420 remove_proc_entry(sb->s_id, ext4_proc_root); 421 } 422 kobject_del(&sbi->s_kobj); 423 } 424 425 int __init ext4_init_sysfs(void) 426 { 427 int ret; 428 429 kobject_set_name(&ext4_kset.kobj, "ext4"); 430 ext4_kset.kobj.parent = fs_kobj; 431 ret = kset_register(&ext4_kset); 432 if (ret) 433 return ret; 434 435 ret = kobject_init_and_add(&ext4_feat, &ext4_feat_ktype, 436 NULL, "features"); 437 if (ret) 438 kset_unregister(&ext4_kset); 439 else 440 ext4_proc_root = proc_mkdir(proc_dirname, NULL); 441 return ret; 442 } 443 444 void ext4_exit_sysfs(void) 445 { 446 kobject_put(&ext4_feat); 447 kset_unregister(&ext4_kset); 448 remove_proc_entry(proc_dirname, NULL); 449 ext4_proc_root = NULL; 450 } 451 452