kernel/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 static const char * const error_actions[] = {
  25         "unregister",
  26         "panic",
  27         NULL
  28 };
  29
  30 write_attribute(attach);
  31 write_attribute(detach);
  32 write_attribute(unregister);
  33 write_attribute(stop);
  34 write_attribute(clear_stats);
  35 write_attribute(trigger_gc);
  36 write_attribute(prune_cache);
  37 write_attribute(flash_vol_create);
  38
  39 read_attribute(bucket_size);
  40 read_attribute(block_size);
  41 read_attribute(nbuckets);
  42 read_attribute(tree_depth);
  43 read_attribute(root_usage_percent);
  44 read_attribute(priority_stats);
  45 read_attribute(btree_cache_size);
  46 read_attribute(btree_cache_max_chain);
  47 read_attribute(cache_available_percent);
  48 read_attribute(written);
  49 read_attribute(btree_written);
  50 read_attribute(metadata_written);
  51 read_attribute(active_journal_entries);
  52
  53 sysfs_time_stats_attribute(btree_gc,    sec, ms);
  54 sysfs_time_stats_attribute(btree_split, sec, us);
  55 sysfs_time_stats_attribute(btree_sort,  ms,  us);
  56 sysfs_time_stats_attribute(btree_read,  ms,  us);
  57
  58 read_attribute(btree_nodes);
  59 read_attribute(btree_used_percent);
  60 read_attribute(average_key_size);
  61 read_attribute(dirty_data);
  62 read_attribute(bset_tree_stats);
  63
  64 read_attribute(state);
  65 read_attribute(cache_read_races);
  66 read_attribute(writeback_keys_done);
  67 read_attribute(writeback_keys_failed);
  68 read_attribute(io_errors);
  69 read_attribute(congested);
  70 rw_attribute(congested_read_threshold_us);
  71 rw_attribute(congested_write_threshold_us);
  72
  73 rw_attribute(sequential_cutoff);
  74 rw_attribute(data_csum);
  75 rw_attribute(cache_mode);
  76 rw_attribute(writeback_metadata);
  77 rw_attribute(writeback_running);
  78 rw_attribute(writeback_percent);
  79 rw_attribute(writeback_delay);
  80 rw_attribute(writeback_rate);
  81
  82 rw_attribute(writeback_rate_update_seconds);
  83 rw_attribute(writeback_rate_d_term);
  84 rw_attribute(writeback_rate_p_term_inverse);
  85 read_attribute(writeback_rate_debug);
  86
  87 read_attribute(stripe_size);
  88 read_attribute(partial_stripes_expensive);
  89
  90 rw_attribute(synchronous);
  91 rw_attribute(journal_delay_ms);
  92 rw_attribute(discard);
  93 rw_attribute(running);
  94 rw_attribute(label);
  95 rw_attribute(readahead);
  96 rw_attribute(errors);
  97 rw_attribute(io_error_limit);
  98 rw_attribute(io_error_halflife);
  99 rw_attribute(verify);
 100 rw_attribute(bypass_torture_test);
 101 rw_attribute(key_merging_disabled);
 102 rw_attribute(gc_always_rewrite);
 103 rw_attribute(expensive_debug_checks);
 104 rw_attribute(cache_replacement_policy);
 105 rw_attribute(btree_shrinker_disabled);
 106 rw_attribute(copy_gc_enabled);
 107 rw_attribute(size);
 108
 109 SHOW(__bch_cached_dev)
 110 {
 111         struct cached_dev *dc = container_of(kobj, struct cached_dev,
 112                                              disk.kobj);
 113         const char *states[] = { "no cache", "clean", "dirty", "inconsistent" };
 114
 115 #define var(stat)               (dc->stat)
 116
 117         if (attr == &sysfs_cache_mode)
 118                 return bch_snprint_string_list(buf, PAGE_SIZE,
 119                                                bch_cache_modes + 1,
 120                                                BDEV_CACHE_MODE(&dc->sb));
 121
 122         sysfs_printf(data_csum,         "%i", dc->disk.data_csum);
 123         var_printf(verify,              "%i");
 124         var_printf(bypass_torture_test, "%i");
 125         var_printf(writeback_metadata,  "%i");
 126         var_printf(writeback_running,   "%i");
 127         var_print(writeback_delay);
 128         var_print(writeback_percent);
 129         sysfs_hprint(writeback_rate,    dc->writeback_rate.rate << 9);
 130
 131         var_print(writeback_rate_update_seconds);
 132         var_print(writeback_rate_d_term);
 133         var_print(writeback_rate_p_term_inverse);
 134
 135         if (attr == &sysfs_writeback_rate_debug) {
 136                 char rate[20];
 137                 char dirty[20];
 138                 char target[20];
 139                 char proportional[20];
 140                 char derivative[20];
 141                 char change[20];
 142                 s64 next_io;
 143
 144                 bch_hprint(rate,        dc->writeback_rate.rate << 9);
 145                 bch_hprint(dirty,       bcache_dev_sectors_dirty(&dc->disk) << 9);
 146                 bch_hprint(target,      dc->writeback_rate_target << 9);
 147                 bch_hprint(proportional,dc->writeback_rate_proportional << 9);
 148                 bch_hprint(derivative,  dc->writeback_rate_derivative << 9);
 149                 bch_hprint(change,      dc->writeback_rate_change << 9);
 150
 151                 next_io = div64_s64(dc->writeback_rate.next - local_clock(),
 152                                     NSEC_PER_MSEC);
 153
 154                 return sprintf(buf,
 155                                "rate:\t\t%s/sec\n"
 156                                "dirty:\t\t%s\n"
 157                                "target:\t\t%s\n"
 158                                "proportional:\t%s\n"
 159                                "derivative:\t%s\n"
 160                                "change:\t\t%s/sec\n"
 161                                "next io:\t%llims\n",
 162                                rate, dirty, target, proportional,
 163                                derivative, change, next_io);
 164         }
 165
 166         sysfs_hprint(dirty_data,
 167                      bcache_dev_sectors_dirty(&dc->disk) << 9);
 168
 169         sysfs_hprint(stripe_size,       dc->disk.stripe_size << 9);
 170         var_printf(partial_stripes_expensive,   "%u");
 171
 172         var_hprint(sequential_cutoff);
 173         var_hprint(readahead);
 174
 175         sysfs_print(running,            atomic_read(&dc->running));
 176         sysfs_print(state,              states[BDEV_STATE(&dc->sb)]);
 177
 178         if (attr == &sysfs_label) {
 179                 memcpy(buf, dc->sb.label, SB_LABEL_SIZE);
 180                 buf[SB_LABEL_SIZE + 1] = '\0';
 181                 strcat(buf, "\n");
 182                 return strlen(buf);
 183         }
 184
 185 #undef var
 186         return 0;
 187 }
 188 SHOW_LOCKED(bch_cached_dev)
 189
 190 STORE(__cached_dev)
 191 {
 192         struct cached_dev *dc = container_of(kobj, struct cached_dev,
 193                                              disk.kobj);
 194         unsigned v = size;
 195         struct cache_set *c;
 196         struct kobj_uevent_env *env;
 197
 198 #define d_strtoul(var)          sysfs_strtoul(var, dc->var)
 199 #define d_strtoul_nonzero(var)  sysfs_strtoul_clamp(var, dc->var, 1, INT_MAX)
 200 #define d_strtoi_h(var)         sysfs_hatoi(var, dc->var)
 201
 202         sysfs_strtoul(data_csum,        dc->disk.data_csum);
 203         d_strtoul(verify);
 204         d_strtoul(bypass_torture_test);
 205         d_strtoul(writeback_metadata);
 206         d_strtoul(writeback_running);
 207         d_strtoul(writeback_delay);
 208
 209         sysfs_strtoul_clamp(writeback_percent, dc->writeback_percent, 0, 40);
 210
 211         sysfs_strtoul_clamp(writeback_rate,
 212                             dc->writeback_rate.rate, 1, INT_MAX);
 213
 214         d_strtoul_nonzero(writeback_rate_update_seconds);
 215         d_strtoul(writeback_rate_d_term);
 216         d_strtoul_nonzero(writeback_rate_p_term_inverse);
 217
 218         d_strtoi_h(sequential_cutoff);
 219         d_strtoi_h(readahead);
 220
 221         if (attr == &sysfs_clear_stats)
 222                 bch_cache_accounting_clear(&dc->accounting);
 223
 224         if (attr == &sysfs_running &&
 225             strtoul_or_return(buf))
 226                 bch_cached_dev_run(dc);
 227
 228         if (attr == &sysfs_cache_mode) {
 229                 ssize_t v = bch_read_string_list(buf, bch_cache_modes + 1);
 230
 231                 if (v < 0)
 232                         return v;
 233
 234                 if ((unsigned) v != BDEV_CACHE_MODE(&dc->sb)) {
 235                         SET_BDEV_CACHE_MODE(&dc->sb, v);
 236                         bch_write_bdev_super(dc, NULL);
 237                 }
 238         }
 239
 240         if (attr == &sysfs_label) {
 241                 if (size > SB_LABEL_SIZE)
 242                         return -EINVAL;
 243                 memcpy(dc->sb.label, buf, size);
 244                 if (size < SB_LABEL_SIZE)
 245                         dc->sb.label[size] = '\0';
 246                 if (size && dc->sb.label[size - 1] == '\n')
 247                         dc->sb.label[size - 1] = '\0';
 248                 bch_write_bdev_super(dc, NULL);
 249                 if (dc->disk.c) {
 250                         memcpy(dc->disk.c->uuids[dc->disk.id].label,
 251                                buf, SB_LABEL_SIZE);
 252                         bch_uuid_write(dc->disk.c);
 253                 }
 254                 env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL);
 255                 if (!env)
 256                         return -ENOMEM;
 257                 add_uevent_var(env, "DRIVER=bcache");
 258                 add_uevent_var(env, "CACHED_UUID=%pU", dc->sb.uuid),
 259                 add_uevent_var(env, "CACHED_LABEL=%s", buf);
 260                 kobject_uevent_env(
 261                         &disk_to_dev(dc->disk.disk)->kobj, KOBJ_CHANGE, env->envp);
 262                 kfree(env);
 263         }
 264
 265         if (attr == &sysfs_attach) {
 266                 if (bch_parse_uuid(buf, dc->sb.set_uuid) < 16)
 267                         return -EINVAL;
 268
 269                 list_for_each_entry(c, &bch_cache_sets, list) {
 270                         v = bch_cached_dev_attach(dc, c);
 271                         if (!v)
 272                                 return size;
 273                 }
 274
 275                 pr_err("Can't attach %s: cache set not found", buf);
 276                 size = v;
 277         }
 278
 279         if (attr == &sysfs_detach && dc->disk.c)
 280                 bch_cached_dev_detach(dc);
 281
 282         if (attr == &sysfs_stop)
 283                 bcache_device_stop(&dc->disk);
 284
 285         return size;
 286 }
 287
 288 STORE(bch_cached_dev)
 289 {
 290         struct cached_dev *dc = container_of(kobj, struct cached_dev,
 291                                              disk.kobj);
 292
 293         mutex_lock(&bch_register_lock);
 294         size = __cached_dev_store(kobj, attr, buf, size);
 295
 296         if (attr == &sysfs_writeback_running)
 297                 bch_writeback_queue(dc);
 298
 299         if (attr == &sysfs_writeback_percent)
 300                 schedule_delayed_work(&dc->writeback_rate_update,
 301                                       dc->writeback_rate_update_seconds * HZ);
 302
 303         mutex_unlock(&bch_register_lock);
 304         return size;
 305 }
 306
 307 static struct attribute *bch_cached_dev_files[] = {
 308         &sysfs_attach,
 309         &sysfs_detach,
 310         &sysfs_stop,
 311 #if 0
 312         &sysfs_data_csum,
 313 #endif
 314         &sysfs_cache_mode,
 315         &sysfs_writeback_metadata,
 316         &sysfs_writeback_running,
 317         &sysfs_writeback_delay,
 318         &sysfs_writeback_percent,
 319         &sysfs_writeback_rate,
 320         &sysfs_writeback_rate_update_seconds,
 321         &sysfs_writeback_rate_d_term,
 322         &sysfs_writeback_rate_p_term_inverse,
 323         &sysfs_writeback_rate_debug,
 324         &sysfs_dirty_data,
 325         &sysfs_stripe_size,
 326         &sysfs_partial_stripes_expensive,
 327         &sysfs_sequential_cutoff,
 328         &sysfs_clear_stats,
 329         &sysfs_running,
 330         &sysfs_state,
 331         &sysfs_label,
 332         &sysfs_readahead,
 333 #ifdef CONFIG_BCACHE_DEBUG
 334         &sysfs_verify,
 335         &sysfs_bypass_torture_test,
 336 #endif
 337         NULL
 338 };
 339 KTYPE(bch_cached_dev);
 340
 341 SHOW(bch_flash_dev)
 342 {
 343         struct bcache_device *d = container_of(kobj, struct bcache_device,
 344                                                kobj);
 345         struct uuid_entry *u = &d->c->uuids[d->id];
 346
 347         sysfs_printf(data_csum, "%i", d->data_csum);
 348         sysfs_hprint(size,      u->sectors << 9);
 349
 350         if (attr == &sysfs_label) {
 351                 memcpy(buf, u->label, SB_LABEL_SIZE);
 352                 buf[SB_LABEL_SIZE + 1] = '\0';
 353                 strcat(buf, "\n");
 354                 return strlen(buf);
 355         }
 356
 357         return 0;
 358 }
 359
 360 STORE(__bch_flash_dev)
 361 {
 362         struct bcache_device *d = container_of(kobj, struct bcache_device,
 363                                                kobj);
 364         struct uuid_entry *u = &d->c->uuids[d->id];
 365
 366         sysfs_strtoul(data_csum,        d->data_csum);
 367
 368         if (attr == &sysfs_size) {
 369                 uint64_t v;
 370                 strtoi_h_or_return(buf, v);
 371
 372                 u->sectors = v >> 9;
 373                 bch_uuid_write(d->c);
 374                 set_capacity(d->disk, u->sectors);
 375         }
 376
 377         if (attr == &sysfs_label) {
 378                 memcpy(u->label, buf, SB_LABEL_SIZE);
 379                 bch_uuid_write(d->c);
 380         }
 381
 382         if (attr == &sysfs_unregister) {
 383                 set_bit(BCACHE_DEV_DETACHING, &d->flags);
 384                 bcache_device_stop(d);
 385         }
 386
 387         return size;
 388 }
 389 STORE_LOCKED(bch_flash_dev)
 390
 391 static struct attribute *bch_flash_dev_files[] = {
 392         &sysfs_unregister,
 393 #if 0
 394         &sysfs_data_csum,
 395 #endif
 396         &sysfs_label,
 397         &sysfs_size,
 398         NULL
 399 };
 400 KTYPE(bch_flash_dev);
 401
 402 struct bset_stats_op {
 403         struct btree_op op;
 404         size_t nodes;
 405         struct bset_stats stats;
 406 };
 407
 408 static int bch_btree_bset_stats(struct btree_op *b_op, struct btree *b)
 409 {
 410         struct bset_stats_op *op = container_of(b_op, struct bset_stats_op, op);
 411
 412         op->nodes++;
 413         bch_btree_keys_stats(&b->keys, &op->stats);
 414
 415         return MAP_CONTINUE;
 416 }
 417
 418 static int bch_bset_print_stats(struct cache_set *c, char *buf)
 419 {
 420         struct bset_stats_op op;
 421         int ret;
 422
 423         memset(&op, 0, sizeof(op));
 424         bch_btree_op_init(&op.op, -1);
 425
 426         ret = bch_btree_map_nodes(&op.op, c, &ZERO_KEY, bch_btree_bset_stats);
 427         if (ret < 0)
 428                 return ret;
 429
 430         return snprintf(buf, PAGE_SIZE,
 431                         "btree nodes:           %zu\n"
 432                         "written sets:          %zu\n"
 433                         "unwritten sets:                %zu\n"
 434                         "written key bytes:     %zu\n"
 435                         "unwritten key bytes:   %zu\n"
 436                         "floats:                        %zu\n"
 437                         "failed:                        %zu\n",
 438                         op.nodes,
 439                         op.stats.sets_written, op.stats.sets_unwritten,
 440                         op.stats.bytes_written, op.stats.bytes_unwritten,
 441                         op.stats.floats, op.stats.failed);
 442 }
 443
 444 static unsigned bch_root_usage(struct cache_set *c)
 445 {
 446         unsigned bytes = 0;
 447         struct bkey *k;
 448         struct btree *b;
 449         struct btree_iter iter;
 450
 451         goto lock_root;
 452
 453         do {
 454                 rw_unlock(false, b);
 455 lock_root:
 456                 b = c->root;
 457                 rw_lock(false, b, b->level);
 458         } while (b != c->root);
 459
 460         for_each_key_filter(&b->keys, k, &iter, bch_ptr_bad)
 461                 bytes += bkey_bytes(k);
 462
 463         rw_unlock(false, b);
 464
 465         return (bytes * 100) / btree_bytes(c);
 466 }
 467
 468 static size_t bch_cache_size(struct cache_set *c)
 469 {
 470         size_t ret = 0;
 471         struct btree *b;
 472
 473         mutex_lock(&c->bucket_lock);
 474         list_for_each_entry(b, &c->btree_cache, list)
 475                 ret += 1 << (b->keys.page_order + PAGE_SHIFT);
 476
 477         mutex_unlock(&c->bucket_lock);
 478         return ret;
 479 }
 480
 481 static unsigned bch_cache_max_chain(struct cache_set *c)
 482 {
 483         unsigned ret = 0;
 484         struct hlist_head *h;
 485
 486         mutex_lock(&c->bucket_lock);
 487
 488         for (h = c->bucket_hash;
 489              h < c->bucket_hash + (1 << BUCKET_HASH_BITS);
 490              h++) {
 491                 unsigned i = 0;
 492                 struct hlist_node *p;
 493
 494                 hlist_for_each(p, h)
 495                         i++;
 496
 497                 ret = max(ret, i);
 498         }
 499
 500         mutex_unlock(&c->bucket_lock);
 501         return ret;
 502 }
 503
 504 static unsigned bch_btree_used(struct cache_set *c)
 505 {
 506         return div64_u64(c->gc_stats.key_bytes * 100,
 507                          (c->gc_stats.nodes ?: 1) * btree_bytes(c));
 508 }
 509
 510 static unsigned bch_average_key_size(struct cache_set *c)
 511 {
 512         return c->gc_stats.nkeys
 513                 ? div64_u64(c->gc_stats.data, c->gc_stats.nkeys)
 514                 : 0;
 515 }
 516
 517 SHOW(__bch_cache_set)
 518 {
 519         struct cache_set *c = container_of(kobj, struct cache_set, kobj);
 520
 521         sysfs_print(synchronous,                CACHE_SYNC(&c->sb));
 522         sysfs_print(journal_delay_ms,           c->journal_delay_ms);
 523         sysfs_hprint(bucket_size,               bucket_bytes(c));
 524         sysfs_hprint(block_size,                block_bytes(c));
 525         sysfs_print(tree_depth,                 c->root->level);
 526         sysfs_print(root_usage_percent,         bch_root_usage(c));
 527
 528         sysfs_hprint(btree_cache_size,          bch_cache_size(c));
 529         sysfs_print(btree_cache_max_chain,      bch_cache_max_chain(c));
 530         sysfs_print(cache_available_percent,    100 - c->gc_stats.in_use);
 531
 532         sysfs_print_time_stats(&c->btree_gc_time,       btree_gc, sec, ms);
 533         sysfs_print_time_stats(&c->btree_split_time,    btree_split, sec, us);
 534         sysfs_print_time_stats(&c->sort.time,           btree_sort, ms, us);
 535         sysfs_print_time_stats(&c->btree_read_time,     btree_read, ms, us);
 536
 537         sysfs_print(btree_used_percent, bch_btree_used(c));
 538         sysfs_print(btree_nodes,        c->gc_stats.nodes);
 539         sysfs_hprint(average_key_size,  bch_average_key_size(c));
 540
 541         sysfs_print(cache_read_races,
 542                     atomic_long_read(&c->cache_read_races));
 543
 544         sysfs_print(writeback_keys_done,
 545                     atomic_long_read(&c->writeback_keys_done));
 546         sysfs_print(writeback_keys_failed,
 547                     atomic_long_read(&c->writeback_keys_failed));
 548
 549         if (attr == &sysfs_errors)
 550                 return bch_snprint_string_list(buf, PAGE_SIZE, error_actions,
 551                                                c->on_error);
 552
 553         /* See count_io_errors for why 88 */
 554         sysfs_print(io_error_halflife,  c->error_decay * 88);
 555         sysfs_print(io_error_limit,     c->error_limit >> IO_ERROR_SHIFT);
 556
 557         sysfs_hprint(congested,
 558                      ((uint64_t) bch_get_congested(c)) << 9);
 559         sysfs_print(congested_read_threshold_us,
 560                     c->congested_read_threshold_us);
 561         sysfs_print(congested_write_threshold_us,
 562                     c->congested_write_threshold_us);
 563
 564         sysfs_print(active_journal_entries,     fifo_used(&c->journal.pin));
 565         sysfs_printf(verify,                    "%i", c->verify);
 566         sysfs_printf(key_merging_disabled,      "%i", c->key_merging_disabled);
 567         sysfs_printf(expensive_debug_checks,
 568                      "%i", c->expensive_debug_checks);
 569         sysfs_printf(gc_always_rewrite,         "%i", c->gc_always_rewrite);
 570         sysfs_printf(btree_shrinker_disabled,   "%i", c->shrinker_disabled);
 571         sysfs_printf(copy_gc_enabled,           "%i", c->copy_gc_enabled);
 572
 573         if (attr == &sysfs_bset_tree_stats)
 574                 return bch_bset_print_stats(c, buf);
 575
 576         return 0;
 577 }
 578 SHOW_LOCKED(bch_cache_set)
 579
 580 STORE(__bch_cache_set)
 581 {
 582         struct cache_set *c = container_of(kobj, struct cache_set, kobj);
 583
 584         if (attr == &sysfs_unregister)
 585                 bch_cache_set_unregister(c);
 586
 587         if (attr == &sysfs_stop)
 588                 bch_cache_set_stop(c);
 589
 590         if (attr == &sysfs_synchronous) {
 591                 bool sync = strtoul_or_return(buf);
 592
 593                 if (sync != CACHE_SYNC(&c->sb)) {
 594                         SET_CACHE_SYNC(&c->sb, sync);
 595                         bcache_write_super(c);
 596                 }
 597         }
 598
 599         if (attr == &sysfs_flash_vol_create) {
 600                 int r;
 601                 uint64_t v;
 602                 strtoi_h_or_return(buf, v);
 603
 604                 r = bch_flash_dev_create(c, v);
 605                 if (r)
 606                         return r;
 607         }
 608
 609         if (attr == &sysfs_clear_stats) {
 610                 atomic_long_set(&c->writeback_keys_done,        0);
 611                 atomic_long_set(&c->writeback_keys_failed,      0);
 612
 613                 memset(&c->gc_stats, 0, sizeof(struct gc_stat));
 614                 bch_cache_accounting_clear(&c->accounting);
 615         }
 616
 617         if (attr == &sysfs_trigger_gc)
 618                 wake_up_gc(c);
 619
 620         if (attr == &sysfs_prune_cache) {
 621                 struct shrink_control sc;
 622                 sc.gfp_mask = GFP_KERNEL;
 623                 sc.nr_to_scan = strtoul_or_return(buf);
 624                 c->shrink.scan_objects(&c->shrink, &sc);
 625         }
 626
 627         sysfs_strtoul(congested_read_threshold_us,
 628                       c->congested_read_threshold_us);
 629         sysfs_strtoul(congested_write_threshold_us,
 630                       c->congested_write_threshold_us);
 631
 632         if (attr == &sysfs_errors) {
 633                 ssize_t v = bch_read_string_list(buf, error_actions);
 634
 635                 if (v < 0)
 636                         return v;
 637
 638                 c->on_error = v;
 639         }
 640
 641         if (attr == &sysfs_io_error_limit)
 642                 c->error_limit = strtoul_or_return(buf) << IO_ERROR_SHIFT;
 643
 644         /* See count_io_errors() for why 88 */
 645         if (attr == &sysfs_io_error_halflife)
 646                 c->error_decay = strtoul_or_return(buf) / 88;
 647
 648         sysfs_strtoul(journal_delay_ms,         c->journal_delay_ms);
 649         sysfs_strtoul(verify,                   c->verify);
 650         sysfs_strtoul(key_merging_disabled,     c->key_merging_disabled);
 651         sysfs_strtoul(expensive_debug_checks,   c->expensive_debug_checks);
 652         sysfs_strtoul(gc_always_rewrite,        c->gc_always_rewrite);
 653         sysfs_strtoul(btree_shrinker_disabled,  c->shrinker_disabled);
 654         sysfs_strtoul(copy_gc_enabled,          c->copy_gc_enabled);
 655
 656         return size;
 657 }
 658 STORE_LOCKED(bch_cache_set)
 659
 660 SHOW(bch_cache_set_internal)
 661 {
 662         struct cache_set *c = container_of(kobj, struct cache_set, internal);
 663         return bch_cache_set_show(&c->kobj, attr, buf);
 664 }
 665
 666 STORE(bch_cache_set_internal)
 667 {
 668         struct cache_set *c = container_of(kobj, struct cache_set, internal);
 669         return bch_cache_set_store(&c->kobj, attr, buf, size);
 670 }
 671
 672 static void bch_cache_set_internal_release(struct kobject *k)
 673 {
 674 }
 675
 676 static struct attribute *bch_cache_set_files[] = {
 677         &sysfs_unregister,
 678         &sysfs_stop,
 679         &sysfs_synchronous,
 680         &sysfs_journal_delay_ms,
 681         &sysfs_flash_vol_create,
 682
 683         &sysfs_bucket_size,
 684         &sysfs_block_size,
 685         &sysfs_tree_depth,
 686         &sysfs_root_usage_percent,
 687         &sysfs_btree_cache_size,
 688         &sysfs_cache_available_percent,
 689
 690         &sysfs_average_key_size,
 691
 692         &sysfs_errors,
 693         &sysfs_io_error_limit,
 694         &sysfs_io_error_halflife,
 695         &sysfs_congested,
 696         &sysfs_congested_read_threshold_us,
 697         &sysfs_congested_write_threshold_us,
 698         &sysfs_clear_stats,
 699         NULL
 700 };
 701 KTYPE(bch_cache_set);
 702
 703 static struct attribute *bch_cache_set_internal_files[] = {
 704         &sysfs_active_journal_entries,
 705
 706         sysfs_time_stats_attribute_list(btree_gc, sec, ms)
 707         sysfs_time_stats_attribute_list(btree_split, sec, us)
 708         sysfs_time_stats_attribute_list(btree_sort, ms, us)
 709         sysfs_time_stats_attribute_list(btree_read, ms, us)
 710
 711         &sysfs_btree_nodes,
 712         &sysfs_btree_used_percent,
 713         &sysfs_btree_cache_max_chain,
 714
 715         &sysfs_bset_tree_stats,
 716         &sysfs_cache_read_races,
 717         &sysfs_writeback_keys_done,
 718         &sysfs_writeback_keys_failed,
 719
 720         &sysfs_trigger_gc,
 721         &sysfs_prune_cache,
 722 #ifdef CONFIG_BCACHE_DEBUG
 723         &sysfs_verify,
 724         &sysfs_key_merging_disabled,
 725         &sysfs_expensive_debug_checks,
 726 #endif
 727         &sysfs_gc_always_rewrite,
 728         &sysfs_btree_shrinker_disabled,
 729         &sysfs_copy_gc_enabled,
 730         NULL
 731 };
 732 KTYPE(bch_cache_set_internal);
 733
 734 SHOW(__bch_cache)
 735 {
 736         struct cache *ca = container_of(kobj, struct cache, kobj);
 737
 738         sysfs_hprint(bucket_size,       bucket_bytes(ca));
 739         sysfs_hprint(block_size,        block_bytes(ca));
 740         sysfs_print(nbuckets,           ca->sb.nbuckets);
 741         sysfs_print(discard,            ca->discard);
 742         sysfs_hprint(written, atomic_long_read(&ca->sectors_written) << 9);
 743         sysfs_hprint(btree_written,
 744                      atomic_long_read(&ca->btree_sectors_written) << 9);
 745         sysfs_hprint(metadata_written,
 746                      (atomic_long_read(&ca->meta_sectors_written) +
 747                       atomic_long_read(&ca->btree_sectors_written)) << 9);
 748
 749         sysfs_print(io_errors,
 750                     atomic_read(&ca->io_errors) >> IO_ERROR_SHIFT);
 751
 752         if (attr == &sysfs_cache_replacement_policy)
 753                 return bch_snprint_string_list(buf, PAGE_SIZE,
 754                                                cache_replacement_policies,
 755                                                CACHE_REPLACEMENT(&ca->sb));
 756
 757         if (attr == &sysfs_priority_stats) {
 758                 int cmp(const void *l, const void *r)
 759                 {       return *((uint16_t *) r) - *((uint16_t *) l); }
 760
 761                 struct bucket *b;
 762                 size_t n = ca->sb.nbuckets, i;
 763                 size_t unused = 0, available = 0, dirty = 0, meta = 0;
 764                 uint64_t sum = 0;
 765                 /* Compute 31 quantiles */
 766                 uint16_t q[31], *p, *cached;
 767                 ssize_t ret;
 768
 769                 cached = p = vmalloc(ca->sb.nbuckets * sizeof(uint16_t));
 770                 if (!p)
 771                         return -ENOMEM;
 772
 773                 mutex_lock(&ca->set->bucket_lock);
 774                 for_each_bucket(b, ca) {
 775                         if (!GC_SECTORS_USED(b))
 776                                 unused++;
 777                         if (GC_MARK(b) == GC_MARK_RECLAIMABLE)
 778                                 available++;
 779                         if (GC_MARK(b) == GC_MARK_DIRTY)
 780                                 dirty++;
 781                         if (GC_MARK(b) == GC_MARK_METADATA)
 782                                 meta++;
 783                 }
 784
 785                 for (i = ca->sb.first_bucket; i < n; i++)
 786                         p[i] = ca->buckets[i].prio;
 787                 mutex_unlock(&ca->set->bucket_lock);
 788
 789                 sort(p, n, sizeof(uint16_t), cmp, NULL);
 790
 791                 while (n &&
 792                        !cached[n - 1])
 793                         --n;
 794
 795                 unused = ca->sb.nbuckets - n;
 796
 797                 while (cached < p + n &&
 798                        *cached == BTREE_PRIO)
 799                         cached++, n--;
 800
 801                 for (i = 0; i < n; i++)
 802                         sum += INITIAL_PRIO - cached[i];
 803
 804                 if (n)
 805                         do_div(sum, n);
 806
 807                 for (i = 0; i < ARRAY_SIZE(q); i++)
 808                         q[i] = INITIAL_PRIO - cached[n * (i + 1) /
 809                                 (ARRAY_SIZE(q) + 1)];
 810
 811                 vfree(p);
 812
 813                 ret = scnprintf(buf, PAGE_SIZE,
 814                                 "Unused:                %zu%%\n"
 815                                 "Clean:         %zu%%\n"
 816                                 "Dirty:         %zu%%\n"
 817                                 "Metadata:      %zu%%\n"
 818                                 "Average:       %llu\n"
 819                                 "Sectors per Q: %zu\n"
 820                                 "Quantiles:     [",
 821                                 unused * 100 / (size_t) ca->sb.nbuckets,
 822                                 available * 100 / (size_t) ca->sb.nbuckets,
 823                                 dirty * 100 / (size_t) ca->sb.nbuckets,
 824                                 meta * 100 / (size_t) ca->sb.nbuckets, sum,
 825                                 n * ca->sb.bucket_size / (ARRAY_SIZE(q) + 1));
 826
 827                 for (i = 0; i < ARRAY_SIZE(q); i++)
 828                         ret += scnprintf(buf + ret, PAGE_SIZE - ret,
 829                                          "%u ", q[i]);
 830                 ret--;
 831
 832                 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "]\n");
 833
 834                 return ret;
 835         }
 836
 837         return 0;
 838 }
 839 SHOW_LOCKED(bch_cache)
 840
 841 STORE(__bch_cache)
 842 {
 843         struct cache *ca = container_of(kobj, struct cache, kobj);
 844
 845         if (attr == &sysfs_discard) {
 846                 bool v = strtoul_or_return(buf);
 847
 848                 if (blk_queue_discard(bdev_get_queue(ca->bdev)))
 849                         ca->discard = v;
 850
 851                 if (v != CACHE_DISCARD(&ca->sb)) {
 852                         SET_CACHE_DISCARD(&ca->sb, v);
 853                         bcache_write_super(ca->set);
 854                 }
 855         }
 856
 857         if (attr == &sysfs_cache_replacement_policy) {
 858                 ssize_t v = bch_read_string_list(buf, cache_replacement_policies);
 859
 860                 if (v < 0)
 861                         return v;
 862
 863                 if ((unsigned) v != CACHE_REPLACEMENT(&ca->sb)) {
 864                         mutex_lock(&ca->set->bucket_lock);
 865                         SET_CACHE_REPLACEMENT(&ca->sb, v);
 866                         mutex_unlock(&ca->set->bucket_lock);
 867
 868                         bcache_write_super(ca->set);
 869                 }
 870         }
 871
 872         if (attr == &sysfs_clear_stats) {
 873                 atomic_long_set(&ca->sectors_written, 0);
 874                 atomic_long_set(&ca->btree_sectors_written, 0);
 875                 atomic_long_set(&ca->meta_sectors_written, 0);
 876                 atomic_set(&ca->io_count, 0);
 877                 atomic_set(&ca->io_errors, 0);
 878         }
 879
 880         return size;
 881 }
 882 STORE_LOCKED(bch_cache)
 883
 884 static struct attribute *bch_cache_files[] = {
 885         &sysfs_bucket_size,
 886         &sysfs_block_size,
 887         &sysfs_nbuckets,
 888         &sysfs_priority_stats,
 889         &sysfs_discard,
 890         &sysfs_written,
 891         &sysfs_btree_written,
 892         &sysfs_metadata_written,
 893         &sysfs_io_errors,
 894         &sysfs_clear_stats,
 895         &sysfs_cache_replacement_policy,
 896         NULL
 897 };
 898 KTYPE(bch_cache);