drivers/md/bcache/sysfs.c

   1 /*
   2  * bcache sysfs interfaces
   3  *
   4  * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
   5  * Copyright 2012 Google, Inc.
   6  */
   7
   8 #include "bcache.h"
   9 #include "sysfs.h"
  10 #include "btree.h"
  11 #include "request.h"
  12 #include "writeback.h"
  13
  14 #include <linux/blkdev.h>
  15 #include <linux/sort.h>
  16
  17 static const char * const cache_replacement_policies[] = {
  18         "lru",
  19         "fifo",
  20         "random",
  21         NULL
  22 };
  23
  24 write_attribute(attach);
  25 write_attribute(detach);
  26 write_attribute(unregister);
  27 write_attribute(stop);
  28 write_attribute(clear_stats);
  29 write_attribute(trigger_gc);
  30 write_attribute(prune_cache);
  31 write_attribute(flash_vol_create);
  32
  33 read_attribute(bucket_size);
  34 read_attribute(block_size);
  35 read_attribute(nbuckets);
  36 read_attribute(tree_depth);
  37 read_attribute(root_usage_percent);
  38 read_attribute(priority_stats);
  39 read_attribute(btree_cache_size);
  40 read_attribute(btree_cache_max_chain);
  41 read_attribute(cache_available_percent);
  42 read_attribute(written);
  43 read_attribute(btree_written);
  44 read_attribute(metadata_written);
  45 read_attribute(active_journal_entries);
  46
  47 sysfs_time_stats_attribute(btree_gc,    sec, ms);
  48 sysfs_time_stats_attribute(btree_split, sec, us);
  49 sysfs_time_stats_attribute(btree_sort,  ms,  us);
  50 sysfs_time_stats_attribute(btree_read,  ms,  us);
  51 sysfs_time_stats_attribute(try_harder,  ms,  us);
  52
  53 read_attribute(btree_nodes);
  54 read_attribute(btree_used_percent);
  55 read_attribute(average_key_size);
  56 read_attribute(dirty_data);
  57 read_attribute(bset_tree_stats);
  58
  59 read_attribute(state);
  60 read_attribute(cache_read_races);
  61 read_attribute(writeback_keys_done);
  62 read_attribute(writeback_keys_failed);
  63 read_attribute(io_errors);
  64 read_attribute(congested);
  65 rw_attribute(congested_read_threshold_us);
  66 rw_attribute(congested_write_threshold_us);
  67
  68 rw_attribute(sequential_cutoff);
  69 rw_attribute(sequential_merge);
  70 rw_attribute(data_csum);
  71 rw_attribute(cache_mode);
  72 rw_attribute(writeback_metadata);
  73 rw_attribute(writeback_running);
  74 rw_attribute(writeback_percent);
  75 rw_attribute(writeback_delay);
  76 rw_attribute(writeback_rate);
  77
  78 rw_attribute(writeback_rate_update_seconds);
  79 rw_attribute(writeback_rate_d_term);
  80 rw_attribute(writeback_rate_p_term_inverse);
  81 rw_attribute(writeback_rate_d_smooth);
  82 read_attribute(writeback_rate_debug);
  83
  84 read_attribute(stripe_size);
  85 read_attribute(partial_stripes_expensive);
  86
  87 rw_attribute(synchronous);
  88 rw_attribute(journal_delay_ms);
  89 rw_attribute(discard);
  90 rw_attribute(running);
  91 rw_attribute(label);
  92 rw_attribute(readahead);
  93 rw_attribute(io_error_limit);
  94 rw_attribute(io_error_halflife);
  95 rw_attribute(verify);
  96 rw_attribute(key_merging_disabled);
  97 rw_attribute(gc_always_rewrite);
  98 rw_attribute(freelist_percent);
  99 rw_attribute(cache_replacement_policy);
 100 rw_attribute(btree_shrinker_disabled);
 101 rw_attribute(copy_gc_enabled);
 102 rw_attribute(size);
 103
 104 SHOW(__bch_cached_dev)
 105 {
 106         struct cached_dev *dc = container_of(kobj, struct cached_dev,
 107                                              disk.kobj);
 108         const char *states[] = { "no cache", "clean", "dirty", "inconsistent" };
 109
 110 #define var(stat)               (dc->stat)
 111
 112         if (attr == &sysfs_cache_mode)
 113                 return bch_snprint_string_list(buf, PAGE_SIZE,
 114                                                bch_cache_modes + 1,
 115                                                BDEV_CACHE_MODE(&dc->sb));
 116
 117         sysfs_printf(data_csum,         "%i", dc->disk.data_csum);
 118         var_printf(verify,              "%i");
 119         var_printf(writeback_metadata,  "%i");
 120         var_printf(writeback_running,   "%i");
 121         var_print(writeback_delay);
 122         var_print(writeback_percent);
 123         sysfs_print(writeback_rate,     dc->writeback_rate.rate);
 124
 125         var_print(writeback_rate_update_seconds);
 126         var_print(writeback_rate_d_term);
 127         var_print(writeback_rate_p_term_inverse);
 128         var_print(writeback_rate_d_smooth);
 129
 130         if (attr == &sysfs_writeback_rate_debug) {
 131                 char dirty[20];
 132                 char derivative[20];
 133                 char target[20];
 134                 bch_hprint(dirty,
 135                            bcache_dev_sectors_dirty(&dc->disk) << 9);
 136                 bch_hprint(derivative,  dc->writeback_rate_derivative << 9);
 137                 bch_hprint(target,      dc->writeback_rate_target << 9);
 138
 139                 return sprintf(buf,
 140                                "rate:\t\t%u\n"
 141                                "change:\t\t%i\n"
 142                                "dirty:\t\t%s\n"
 143                                "derivative:\t%s\n"
 144                                "target:\t\t%s\n",
 145                                dc->writeback_rate.rate,
 146                                dc->writeback_rate_change,
 147                                dirty, derivative, target);
 148         }
 149
 150         sysfs_hprint(dirty_data,
 151                      bcache_dev_sectors_dirty(&dc->disk) << 9);
 152
 153         sysfs_hprint(stripe_size,       (1 << dc->disk.stripe_size_bits) << 9);
 154         var_printf(partial_stripes_expensive,   "%u");
 155
 156         var_printf(sequential_merge,    "%i");
 157         var_hprint(sequential_cutoff);
 158         var_hprint(readahead);
 159
 160         sysfs_print(running,            atomic_read(&dc->running));
 161         sysfs_print(state,              states[BDEV_STATE(&dc->sb)]);
 162
 163         if (attr == &sysfs_label) {
 164                 memcpy(buf, dc->sb.label, SB_LABEL_SIZE);
 165                 buf[SB_LABEL_SIZE + 1] = '\0';
 166                 strcat(buf, "\n");
 167                 return strlen(buf);
 168         }
 169
 170 #undef var
 171         return 0;
 172 }
 173 SHOW_LOCKED(bch_cached_dev)
 174
 175 STORE(__cached_dev)
 176 {
 177         struct cached_dev *dc = container_of(kobj, struct cached_dev,
 178                                              disk.kobj);
 179         unsigned v = size;
 180         struct cache_set *c;
 181         struct kobj_uevent_env *env;
 182
 183 #define d_strtoul(var)          sysfs_strtoul(var, dc->var)
 184 #define d_strtoi_h(var)         sysfs_hatoi(var, dc->var)
 185
 186         sysfs_strtoul(data_csum,        dc->disk.data_csum);
 187         d_strtoul(verify);
 188         d_strtoul(writeback_metadata);
 189         d_strtoul(writeback_running);
 190         d_strtoul(writeback_delay);
 191         sysfs_strtoul_clamp(writeback_rate,
 192                             dc->writeback_rate.rate, 1, 1000000);
 193         sysfs_strtoul_clamp(writeback_percent, dc->writeback_percent, 0, 40);
 194
 195         d_strtoul(writeback_rate_update_seconds);
 196         d_strtoul(writeback_rate_d_term);
 197         d_strtoul(writeback_rate_p_term_inverse);
 198         sysfs_strtoul_clamp(writeback_rate_p_term_inverse,
 199                             dc->writeback_rate_p_term_inverse, 1, INT_MAX);
 200         d_strtoul(writeback_rate_d_smooth);
 201
 202         d_strtoul(sequential_merge);
 203         d_strtoi_h(sequential_cutoff);
 204         d_strtoi_h(readahead);
 205
 206         if (attr == &sysfs_clear_stats)
 207                 bch_cache_accounting_clear(&dc->accounting);
 208
 209         if (attr == &sysfs_running &&
 210             strtoul_or_return(buf))
 211                 bch_cached_dev_run(dc);
 212
 213         if (attr == &sysfs_cache_mode) {
 214                 ssize_t v = bch_read_string_list(buf, bch_cache_modes + 1);
 215
 216                 if (v < 0)
 217                         return v;
 218
 219                 if ((unsigned) v != BDEV_CACHE_MODE(&dc->sb)) {
 220                         SET_BDEV_CACHE_MODE(&dc->sb, v);
 221                         bch_write_bdev_super(dc, NULL);
 222                 }
 223         }
 224
 225         if (attr == &sysfs_label) {
 226                 if (size > SB_LABEL_SIZE)
 227                         return -EINVAL;
 228                 memcpy(dc->sb.label, buf, size);
 229                 if (size < SB_LABEL_SIZE)
 230                         dc->sb.label[size] = '\0';
 231                 if (size && dc->sb.label[size - 1] == '\n')
 232                         dc->sb.label[size - 1] = '\0';
 233                 bch_write_bdev_super(dc, NULL);
 234                 if (dc->disk.c) {
 235                         memcpy(dc->disk.c->uuids[dc->disk.id].label,
 236                                buf, SB_LABEL_SIZE);
 237                         bch_uuid_write(dc->disk.c);
 238                 }
 239                 env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL);
 240                 if (!env)
 241                         return -ENOMEM;
 242                 add_uevent_var(env, "DRIVER=bcache");
 243                 add_uevent_var(env, "CACHED_UUID=%pU", dc->sb.uuid),
 244                 add_uevent_var(env, "CACHED_LABEL=%s", buf);
 245                 kobject_uevent_env(
 246                         &disk_to_dev(dc->disk.disk)->kobj, KOBJ_CHANGE, env->envp);
 247                 kfree(env);
 248         }
 249
 250         if (attr == &sysfs_attach) {
 251                 if (bch_parse_uuid(buf, dc->sb.set_uuid) < 16)
 252                         return -EINVAL;
 253
 254                 list_for_each_entry(c, &bch_cache_sets, list) {
 255                         v = bch_cached_dev_attach(dc, c);
 256                         if (!v)
 257                                 return size;
 258                 }
 259
 260                 pr_err("Can't attach %s: cache set not found", buf);
 261                 size = v;
 262         }
 263
 264         if (attr == &sysfs_detach && dc->disk.c)
 265                 bch_cached_dev_detach(dc);
 266
 267         if (attr == &sysfs_stop)
 268                 bcache_device_stop(&dc->disk);
 269
 270         return size;
 271 }
 272
 273 STORE(bch_cached_dev)
 274 {
 275         struct cached_dev *dc = container_of(kobj, struct cached_dev,
 276                                              disk.kobj);
 277
 278         mutex_lock(&bch_register_lock);
 279         size = __cached_dev_store(kobj, attr, buf, size);
 280
 281         if (attr == &sysfs_writeback_running)
 282                 bch_writeback_queue(dc);
 283
 284         if (attr == &sysfs_writeback_percent)
 285                 schedule_delayed_work(&dc->writeback_rate_update,
 286                                       dc->writeback_rate_update_seconds * HZ);
 287
 288         mutex_unlock(&bch_register_lock);
 289         return size;
 290 }
 291
 292 static struct attribute *bch_cached_dev_files[] = {
 293         &sysfs_attach,
 294         &sysfs_detach,
 295         &sysfs_stop,
 296 #if 0
 297         &sysfs_data_csum,
 298 #endif
 299         &sysfs_cache_mode,
 300         &sysfs_writeback_metadata,
 301         &sysfs_writeback_running,
 302         &sysfs_writeback_delay,
 303         &sysfs_writeback_percent,
 304         &sysfs_writeback_rate,
 305         &sysfs_writeback_rate_update_seconds,
 306         &sysfs_writeback_rate_d_term,
 307         &sysfs_writeback_rate_p_term_inverse,
 308         &sysfs_writeback_rate_d_smooth,
 309         &sysfs_writeback_rate_debug,
 310         &sysfs_dirty_data,
 311         &sysfs_stripe_size,
 312         &sysfs_partial_stripes_expensive,
 313         &sysfs_sequential_cutoff,
 314         &sysfs_sequential_merge,
 315         &sysfs_clear_stats,
 316         &sysfs_running,
 317         &sysfs_state,
 318         &sysfs_label,
 319         &sysfs_readahead,
 320 #ifdef CONFIG_BCACHE_DEBUG
 321         &sysfs_verify,
 322 #endif
 323         NULL
 324 };
 325 KTYPE(bch_cached_dev);
 326
 327 SHOW(bch_flash_dev)
 328 {
 329         struct bcache_device *d = container_of(kobj, struct bcache_device,
 330                                                kobj);
 331         struct uuid_entry *u = &d->c->uuids[d->id];
 332
 333         sysfs_printf(data_csum, "%i", d->data_csum);
 334         sysfs_hprint(size,      u->sectors << 9);
 335
 336         if (attr == &sysfs_label) {
 337                 memcpy(buf, u->label, SB_LABEL_SIZE);
 338                 buf[SB_LABEL_SIZE + 1] = '\0';
 339                 strcat(buf, "\n");
 340                 return strlen(buf);
 341         }
 342
 343         return 0;
 344 }
 345
 346 STORE(__bch_flash_dev)
 347 {
 348         struct bcache_device *d = container_of(kobj, struct bcache_device,
 349                                                kobj);
 350         struct uuid_entry *u = &d->c->uuids[d->id];
 351
 352         sysfs_strtoul(data_csum,        d->data_csum);
 353
 354         if (attr == &sysfs_size) {
 355                 uint64_t v;
 356                 strtoi_h_or_return(buf, v);
 357
 358                 u->sectors = v >> 9;
 359                 bch_uuid_write(d->c);
 360                 set_capacity(d->disk, u->sectors);
 361         }
 362
 363         if (attr == &sysfs_label) {
 364                 memcpy(u->label, buf, SB_LABEL_SIZE);
 365                 bch_uuid_write(d->c);
 366         }
 367
 368         if (attr == &sysfs_unregister) {
 369                 atomic_set(&d->detaching, 1);
 370                 bcache_device_stop(d);
 371         }
 372
 373         return size;
 374 }
 375 STORE_LOCKED(bch_flash_dev)
 376
 377 static struct attribute *bch_flash_dev_files[] = {
 378         &sysfs_unregister,
 379 #if 0
 380         &sysfs_data_csum,
 381 #endif
 382         &sysfs_label,
 383         &sysfs_size,
 384         NULL
 385 };
 386 KTYPE(bch_flash_dev);
 387
 388 SHOW(__bch_cache_set)
 389 {
 390         unsigned root_usage(struct cache_set *c)
 391         {
 392                 unsigned bytes = 0;
 393                 struct bkey *k;
 394                 struct btree *b;
 395                 struct btree_iter iter;
 396
 397                 goto lock_root;
 398
 399                 do {
 400                         rw_unlock(false, b);
 401 lock_root:
 402                         b = c->root;
 403                         rw_lock(false, b, b->level);
 404                 } while (b != c->root);
 405
 406                 for_each_key_filter(b, k, &iter, bch_ptr_bad)
 407                         bytes += bkey_bytes(k);
 408
 409                 rw_unlock(false, b);
 410
 411                 return (bytes * 100) / btree_bytes(c);
 412         }
 413
 414         size_t cache_size(struct cache_set *c)
 415         {
 416                 size_t ret = 0;
 417                 struct btree *b;
 418
 419                 mutex_lock(&c->bucket_lock);
 420                 list_for_each_entry(b, &c->btree_cache, list)
 421                         ret += 1 << (b->page_order + PAGE_SHIFT);
 422
 423                 mutex_unlock(&c->bucket_lock);
 424                 return ret;
 425         }
 426
 427         unsigned cache_max_chain(struct cache_set *c)
 428         {
 429                 unsigned ret = 0;
 430                 struct hlist_head *h;
 431
 432                 mutex_lock(&c->bucket_lock);
 433
 434                 for (h = c->bucket_hash;
 435                      h < c->bucket_hash + (1 << BUCKET_HASH_BITS);
 436                      h++) {
 437                         unsigned i = 0;
 438                         struct hlist_node *p;
 439
 440                         hlist_for_each(p, h)
 441                                 i++;
 442
 443                         ret = max(ret, i);
 444                 }
 445
 446                 mutex_unlock(&c->bucket_lock);
 447                 return ret;
 448         }
 449
 450         unsigned btree_used(struct cache_set *c)
 451         {
 452                 return div64_u64(c->gc_stats.key_bytes * 100,
 453                                  (c->gc_stats.nodes ?: 1) * btree_bytes(c));
 454         }
 455
 456         unsigned average_key_size(struct cache_set *c)
 457         {
 458                 return c->gc_stats.nkeys
 459                         ? div64_u64(c->gc_stats.data, c->gc_stats.nkeys)
 460                         : 0;
 461         }
 462
 463         struct cache_set *c = container_of(kobj, struct cache_set, kobj);
 464
 465         sysfs_print(synchronous,                CACHE_SYNC(&c->sb));
 466         sysfs_print(journal_delay_ms,           c->journal_delay_ms);
 467         sysfs_hprint(bucket_size,               bucket_bytes(c));
 468         sysfs_hprint(block_size,                block_bytes(c));
 469         sysfs_print(tree_depth,                 c->root->level);
 470         sysfs_print(root_usage_percent,         root_usage(c));
 471
 472         sysfs_hprint(btree_cache_size,          cache_size(c));
 473         sysfs_print(btree_cache_max_chain,      cache_max_chain(c));
 474         sysfs_print(cache_available_percent,    100 - c->gc_stats.in_use);
 475
 476         sysfs_print_time_stats(&c->btree_gc_time,       btree_gc, sec, ms);
 477         sysfs_print_time_stats(&c->btree_split_time,    btree_split, sec, us);
 478         sysfs_print_time_stats(&c->sort_time,           btree_sort, ms, us);
 479         sysfs_print_time_stats(&c->btree_read_time,     btree_read, ms, us);
 480         sysfs_print_time_stats(&c->try_harder_time,     try_harder, ms, us);
 481
 482         sysfs_print(btree_used_percent, btree_used(c));
 483         sysfs_print(btree_nodes,        c->gc_stats.nodes);
 484         sysfs_hprint(dirty_data,        c->gc_stats.dirty);
 485         sysfs_hprint(average_key_size,  average_key_size(c));
 486
 487         sysfs_print(cache_read_races,
 488                     atomic_long_read(&c->cache_read_races));
 489
 490         sysfs_print(writeback_keys_done,
 491                     atomic_long_read(&c->writeback_keys_done));
 492         sysfs_print(writeback_keys_failed,
 493                     atomic_long_read(&c->writeback_keys_failed));
 494
 495         /* See count_io_errors for why 88 */
 496         sysfs_print(io_error_halflife,  c->error_decay * 88);
 497         sysfs_print(io_error_limit,     c->error_limit >> IO_ERROR_SHIFT);
 498
 499         sysfs_hprint(congested,
 500                      ((uint64_t) bch_get_congested(c)) << 9);
 501         sysfs_print(congested_read_threshold_us,
 502                     c->congested_read_threshold_us);
 503         sysfs_print(congested_write_threshold_us,
 504                     c->congested_write_threshold_us);
 505
 506         sysfs_print(active_journal_entries,     fifo_used(&c->journal.pin));
 507         sysfs_printf(verify,                    "%i", c->verify);
 508         sysfs_printf(key_merging_disabled,      "%i", c->key_merging_disabled);
 509         sysfs_printf(gc_always_rewrite,         "%i", c->gc_always_rewrite);
 510         sysfs_printf(btree_shrinker_disabled,   "%i", c->shrinker_disabled);
 511         sysfs_printf(copy_gc_enabled,           "%i", c->copy_gc_enabled);
 512
 513         if (attr == &sysfs_bset_tree_stats)
 514                 return bch_bset_print_stats(c, buf);
 515
 516         return 0;
 517 }
 518 SHOW_LOCKED(bch_cache_set)
 519
 520 STORE(__bch_cache_set)
 521 {
 522         struct cache_set *c = container_of(kobj, struct cache_set, kobj);
 523
 524         if (attr == &sysfs_unregister)
 525                 bch_cache_set_unregister(c);
 526
 527         if (attr == &sysfs_stop)
 528                 bch_cache_set_stop(c);
 529
 530         if (attr == &sysfs_synchronous) {
 531                 bool sync = strtoul_or_return(buf);
 532
 533                 if (sync != CACHE_SYNC(&c->sb)) {
 534                         SET_CACHE_SYNC(&c->sb, sync);
 535                         bcache_write_super(c);
 536                 }
 537         }
 538
 539         if (attr == &sysfs_flash_vol_create) {
 540                 int r;
 541                 uint64_t v;
 542                 strtoi_h_or_return(buf, v);
 543
 544                 r = bch_flash_dev_create(c, v);
 545                 if (r)
 546                         return r;
 547         }
 548
 549         if (attr == &sysfs_clear_stats) {
 550                 atomic_long_set(&c->writeback_keys_done,        0);
 551                 atomic_long_set(&c->writeback_keys_failed,      0);
 552
 553                 memset(&c->gc_stats, 0, sizeof(struct gc_stat));
 554                 bch_cache_accounting_clear(&c->accounting);
 555         }
 556
 557         if (attr == &sysfs_trigger_gc)
 558                 bch_queue_gc(c);
 559
 560         if (attr == &sysfs_prune_cache) {
 561                 struct shrink_control sc;
 562                 sc.gfp_mask = GFP_KERNEL;
 563                 sc.nr_to_scan = strtoul_or_return(buf);
 564                 c->shrink.scan_objects(&c->shrink, &sc);
 565         }
 566
 567         sysfs_strtoul(congested_read_threshold_us,
 568                       c->congested_read_threshold_us);
 569         sysfs_strtoul(congested_write_threshold_us,
 570                       c->congested_write_threshold_us);
 571
 572         if (attr == &sysfs_io_error_limit)
 573                 c->error_limit = strtoul_or_return(buf) << IO_ERROR_SHIFT;
 574
 575         /* See count_io_errors() for why 88 */
 576         if (attr == &sysfs_io_error_halflife)
 577                 c->error_decay = strtoul_or_return(buf) / 88;
 578
 579         sysfs_strtoul(journal_delay_ms,         c->journal_delay_ms);
 580         sysfs_strtoul(verify,                   c->verify);
 581         sysfs_strtoul(key_merging_disabled,     c->key_merging_disabled);
 582         sysfs_strtoul(gc_always_rewrite,        c->gc_always_rewrite);
 583         sysfs_strtoul(btree_shrinker_disabled,  c->shrinker_disabled);
 584         sysfs_strtoul(copy_gc_enabled,          c->copy_gc_enabled);
 585
 586         return size;
 587 }
 588 STORE_LOCKED(bch_cache_set)
 589
 590 SHOW(bch_cache_set_internal)
 591 {
 592         struct cache_set *c = container_of(kobj, struct cache_set, internal);
 593         return bch_cache_set_show(&c->kobj, attr, buf);
 594 }
 595
 596 STORE(bch_cache_set_internal)
 597 {
 598         struct cache_set *c = container_of(kobj, struct cache_set, internal);
 599         return bch_cache_set_store(&c->kobj, attr, buf, size);
 600 }
 601
 602 static void bch_cache_set_internal_release(struct kobject *k)
 603 {
 604 }
 605
 606 static struct attribute *bch_cache_set_files[] = {
 607         &sysfs_unregister,
 608         &sysfs_stop,
 609         &sysfs_synchronous,
 610         &sysfs_journal_delay_ms,
 611         &sysfs_flash_vol_create,
 612
 613         &sysfs_bucket_size,
 614         &sysfs_block_size,
 615         &sysfs_tree_depth,
 616         &sysfs_root_usage_percent,
 617         &sysfs_btree_cache_size,
 618         &sysfs_cache_available_percent,
 619
 620         &sysfs_average_key_size,
 621         &sysfs_dirty_data,
 622
 623         &sysfs_io_error_limit,
 624         &sysfs_io_error_halflife,
 625         &sysfs_congested,
 626         &sysfs_congested_read_threshold_us,
 627         &sysfs_congested_write_threshold_us,
 628         &sysfs_clear_stats,
 629         NULL
 630 };
 631 KTYPE(bch_cache_set);
 632
 633 static struct attribute *bch_cache_set_internal_files[] = {
 634         &sysfs_active_journal_entries,
 635
 636         sysfs_time_stats_attribute_list(btree_gc, sec, ms)
 637         sysfs_time_stats_attribute_list(btree_split, sec, us)
 638         sysfs_time_stats_attribute_list(btree_sort, ms, us)
 639         sysfs_time_stats_attribute_list(btree_read, ms, us)
 640         sysfs_time_stats_attribute_list(try_harder, ms, us)
 641
 642         &sysfs_btree_nodes,
 643         &sysfs_btree_used_percent,
 644         &sysfs_btree_cache_max_chain,
 645
 646         &sysfs_bset_tree_stats,
 647         &sysfs_cache_read_races,
 648         &sysfs_writeback_keys_done,
 649         &sysfs_writeback_keys_failed,
 650
 651         &sysfs_trigger_gc,
 652         &sysfs_prune_cache,
 653 #ifdef CONFIG_BCACHE_DEBUG
 654         &sysfs_verify,
 655         &sysfs_key_merging_disabled,
 656 #endif
 657         &sysfs_gc_always_rewrite,
 658         &sysfs_btree_shrinker_disabled,
 659         &sysfs_copy_gc_enabled,
 660         NULL
 661 };
 662 KTYPE(bch_cache_set_internal);
 663
 664 SHOW(__bch_cache)
 665 {
 666         struct cache *ca = container_of(kobj, struct cache, kobj);
 667
 668         sysfs_hprint(bucket_size,       bucket_bytes(ca));
 669         sysfs_hprint(block_size,        block_bytes(ca));
 670         sysfs_print(nbuckets,           ca->sb.nbuckets);
 671         sysfs_print(discard,            ca->discard);
 672         sysfs_hprint(written, atomic_long_read(&ca->sectors_written) << 9);
 673         sysfs_hprint(btree_written,
 674                      atomic_long_read(&ca->btree_sectors_written) << 9);
 675         sysfs_hprint(metadata_written,
 676                      (atomic_long_read(&ca->meta_sectors_written) +
 677                       atomic_long_read(&ca->btree_sectors_written)) << 9);
 678
 679         sysfs_print(io_errors,
 680                     atomic_read(&ca->io_errors) >> IO_ERROR_SHIFT);
 681
 682         sysfs_print(freelist_percent, ca->free.size * 100 /
 683                     ((size_t) ca->sb.nbuckets));
 684
 685         if (attr == &sysfs_cache_replacement_policy)
 686                 return bch_snprint_string_list(buf, PAGE_SIZE,
 687                                                cache_replacement_policies,
 688                                                CACHE_REPLACEMENT(&ca->sb));
 689
 690         if (attr == &sysfs_priority_stats) {
 691                 int cmp(const void *l, const void *r)
 692                 {       return *((uint16_t *) r) - *((uint16_t *) l); }
 693
 694                 size_t n = ca->sb.nbuckets, i, unused, btree;
 695                 uint64_t sum = 0;
 696                 /* Compute 31 quantiles */
 697                 uint16_t q[31], *p, *cached;
 698                 ssize_t ret;
 699
 700                 cached = p = vmalloc(ca->sb.nbuckets * sizeof(uint16_t));
 701                 if (!p)
 702                         return -ENOMEM;
 703
 704                 mutex_lock(&ca->set->bucket_lock);
 705                 for (i = ca->sb.first_bucket; i < n; i++)
 706                         p[i] = ca->buckets[i].prio;
 707                 mutex_unlock(&ca->set->bucket_lock);
 708
 709                 sort(p, n, sizeof(uint16_t), cmp, NULL);
 710
 711                 while (n &&
 712                        !cached[n - 1])
 713                         --n;
 714
 715                 unused = ca->sb.nbuckets - n;
 716
 717                 while (cached < p + n &&
 718                        *cached == BTREE_PRIO)
 719                         cached++;
 720
 721                 btree = cached - p;
 722                 n -= btree;
 723
 724                 for (i = 0; i < n; i++)
 725                         sum += INITIAL_PRIO - cached[i];
 726
 727                 if (n)
 728                         do_div(sum, n);
 729
 730                 for (i = 0; i < ARRAY_SIZE(q); i++)
 731                         q[i] = INITIAL_PRIO - cached[n * (i + 1) /
 732                                 (ARRAY_SIZE(q) + 1)];
 733
 734                 vfree(p);
 735
 736                 ret = scnprintf(buf, PAGE_SIZE,
 737                                 "Unused:                %zu%%\n"
 738                                 "Metadata:      %zu%%\n"
 739                                 "Average:       %llu\n"
 740                                 "Sectors per Q: %zu\n"
 741                                 "Quantiles:     [",
 742                                 unused * 100 / (size_t) ca->sb.nbuckets,
 743                                 btree * 100 / (size_t) ca->sb.nbuckets, sum,
 744                                 n * ca->sb.bucket_size / (ARRAY_SIZE(q) + 1));
 745
 746                 for (i = 0; i < ARRAY_SIZE(q); i++)
 747                         ret += scnprintf(buf + ret, PAGE_SIZE - ret,
 748                                          "%u ", q[i]);
 749                 ret--;
 750
 751                 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "]\n");
 752
 753                 return ret;
 754         }
 755
 756         return 0;
 757 }
 758 SHOW_LOCKED(bch_cache)
 759
 760 STORE(__bch_cache)
 761 {
 762         struct cache *ca = container_of(kobj, struct cache, kobj);
 763
 764         if (attr == &sysfs_discard) {
 765                 bool v = strtoul_or_return(buf);
 766
 767                 if (blk_queue_discard(bdev_get_queue(ca->bdev)))
 768                         ca->discard = v;
 769
 770                 if (v != CACHE_DISCARD(&ca->sb)) {
 771                         SET_CACHE_DISCARD(&ca->sb, v);
 772                         bcache_write_super(ca->set);
 773                 }
 774         }
 775
 776         if (attr == &sysfs_cache_replacement_policy) {
 777                 ssize_t v = bch_read_string_list(buf, cache_replacement_policies);
 778
 779                 if (v < 0)
 780                         return v;
 781
 782                 if ((unsigned) v != CACHE_REPLACEMENT(&ca->sb)) {
 783                         mutex_lock(&ca->set->bucket_lock);
 784                         SET_CACHE_REPLACEMENT(&ca->sb, v);
 785                         mutex_unlock(&ca->set->bucket_lock);
 786
 787                         bcache_write_super(ca->set);
 788                 }
 789         }
 790
 791         if (attr == &sysfs_freelist_percent) {
 792                 DECLARE_FIFO(long, free);
 793                 long i;
 794                 size_t p = strtoul_or_return(buf);
 795
 796                 p = clamp_t(size_t,
 797                             ((size_t) ca->sb.nbuckets * p) / 100,
 798                             roundup_pow_of_two(ca->sb.nbuckets) >> 9,
 799                             ca->sb.nbuckets / 2);
 800
 801                 if (!init_fifo_exact(&free, p, GFP_KERNEL))
 802                         return -ENOMEM;
 803
 804                 mutex_lock(&ca->set->bucket_lock);
 805
 806                 fifo_move(&free, &ca->free);
 807                 fifo_swap(&free, &ca->free);
 808
 809                 mutex_unlock(&ca->set->bucket_lock);
 810
 811                 while (fifo_pop(&free, i))
 812                         atomic_dec(&ca->buckets[i].pin);
 813
 814                 free_fifo(&free);
 815         }
 816
 817         if (attr == &sysfs_clear_stats) {
 818                 atomic_long_set(&ca->sectors_written, 0);
 819                 atomic_long_set(&ca->btree_sectors_written, 0);
 820                 atomic_long_set(&ca->meta_sectors_written, 0);
 821                 atomic_set(&ca->io_count, 0);
 822                 atomic_set(&ca->io_errors, 0);
 823         }
 824
 825         return size;
 826 }
 827 STORE_LOCKED(bch_cache)
 828
 829 static struct attribute *bch_cache_files[] = {
 830         &sysfs_bucket_size,
 831         &sysfs_block_size,
 832         &sysfs_nbuckets,
 833         &sysfs_priority_stats,
 834         &sysfs_discard,
 835         &sysfs_written,
 836         &sysfs_btree_written,
 837         &sysfs_metadata_written,
 838         &sysfs_io_errors,
 839         &sysfs_clear_stats,
 840         &sysfs_freelist_percent,
 841         &sysfs_cache_replacement_policy,
 842         NULL
 843 };
 844 KTYPE(bch_cache);