drivers/md/bcache/sysfs.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * bcache sysfs interfaces
   4  *
   5  * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
   6  * Copyright 2012 Google, Inc.
   7  */
   8
   9 #include "bcache.h"
  10 #include "sysfs.h"
  11 #include "btree.h"
  12 #include "request.h"
  13 #include "writeback.h"
  14 #include "features.h"
  15
  16 #include <linux/blkdev.h>
  17 #include <linux/sort.h>
  18 #include <linux/sched/clock.h>
  19
  20 extern bool bcache_is_reboot;
  21
  22 /* Default is 0 ("writethrough") */
  23 static const char * const bch_cache_modes[] = {
  24         "writethrough",
  25         "writeback",
  26         "writearound",
  27         "none",
  28         NULL
  29 };
  30
  31 static const char * const bch_reada_cache_policies[] = {
  32         "all",
  33         "meta-only",
  34         NULL
  35 };
  36
  37 /* Default is 0 ("auto") */
  38 static const char * const bch_stop_on_failure_modes[] = {
  39         "auto",
  40         "always",
  41         NULL
  42 };
  43
  44 static const char * const cache_replacement_policies[] = {
  45         "lru",
  46         "fifo",
  47         "random",
  48         NULL
  49 };
  50
  51 static const char * const error_actions[] = {
  52         "unregister",
  53         "panic",
  54         NULL
  55 };
  56
  57 write_attribute(attach);
  58 write_attribute(detach);
  59 write_attribute(unregister);
  60 write_attribute(stop);
  61 write_attribute(clear_stats);
  62 write_attribute(trigger_gc);
  63 write_attribute(prune_cache);
  64 write_attribute(flash_vol_create);
  65
  66 read_attribute(bucket_size);
  67 read_attribute(block_size);
  68 read_attribute(nbuckets);
  69 read_attribute(tree_depth);
  70 read_attribute(root_usage_percent);
  71 read_attribute(priority_stats);
  72 read_attribute(btree_cache_size);
  73 read_attribute(btree_cache_max_chain);
  74 read_attribute(cache_available_percent);
  75 read_attribute(written);
  76 read_attribute(btree_written);
  77 read_attribute(metadata_written);
  78 read_attribute(active_journal_entries);
  79 read_attribute(backing_dev_name);
  80 read_attribute(backing_dev_uuid);
  81
  82 sysfs_time_stats_attribute(btree_gc,    sec, ms);
  83 sysfs_time_stats_attribute(btree_split, sec, us);
  84 sysfs_time_stats_attribute(btree_sort,  ms,  us);
  85 sysfs_time_stats_attribute(btree_read,  ms,  us);
  86
  87 read_attribute(btree_nodes);
  88 read_attribute(btree_used_percent);
  89 read_attribute(average_key_size);
  90 read_attribute(dirty_data);
  91 read_attribute(bset_tree_stats);
  92 read_attribute(feature_compat);
  93 read_attribute(feature_ro_compat);
  94 read_attribute(feature_incompat);
  95
  96 read_attribute(state);
  97 read_attribute(cache_read_races);
  98 read_attribute(reclaim);
  99 read_attribute(reclaimed_journal_buckets);
 100 read_attribute(flush_write);
 101 read_attribute(writeback_keys_done);
 102 read_attribute(writeback_keys_failed);
 103 read_attribute(io_errors);
 104 read_attribute(congested);
 105 read_attribute(cutoff_writeback);
 106 read_attribute(cutoff_writeback_sync);
 107 rw_attribute(congested_read_threshold_us);
 108 rw_attribute(congested_write_threshold_us);
 109
 110 rw_attribute(sequential_cutoff);
 111 rw_attribute(data_csum);
 112 rw_attribute(cache_mode);
 113 rw_attribute(readahead_cache_policy);
 114 rw_attribute(stop_when_cache_set_failed);
 115 rw_attribute(writeback_metadata);
 116 rw_attribute(writeback_running);
 117 rw_attribute(writeback_percent);
 118 rw_attribute(writeback_delay);
 119 rw_attribute(writeback_rate);
 120
 121 rw_attribute(writeback_rate_update_seconds);
 122 rw_attribute(writeback_rate_i_term_inverse);
 123 rw_attribute(writeback_rate_p_term_inverse);
 124 rw_attribute(writeback_rate_minimum);
 125 read_attribute(writeback_rate_debug);
 126
 127 read_attribute(stripe_size);
 128 read_attribute(partial_stripes_expensive);
 129
 130 rw_attribute(synchronous);
 131 rw_attribute(journal_delay_ms);
 132 rw_attribute(io_disable);
 133 rw_attribute(discard);
 134 rw_attribute(running);
 135 rw_attribute(label);
 136 rw_attribute(readahead);
 137 rw_attribute(errors);
 138 rw_attribute(io_error_limit);
 139 rw_attribute(io_error_halflife);
 140 rw_attribute(verify);
 141 rw_attribute(bypass_torture_test);
 142 rw_attribute(key_merging_disabled);
 143 rw_attribute(gc_always_rewrite);
 144 rw_attribute(expensive_debug_checks);
 145 rw_attribute(cache_replacement_policy);
 146 rw_attribute(btree_shrinker_disabled);
 147 rw_attribute(copy_gc_enabled);
 148 rw_attribute(idle_max_writeback_rate);
 149 rw_attribute(gc_after_writeback);
 150 rw_attribute(size);
 151
 152 static ssize_t bch_snprint_string_list(char *buf,
 153                                        size_t size,
 154                                        const char * const list[],
 155                                        size_t selected)
 156 {
 157         char *out = buf;
 158         size_t i;
 159
 160         for (i = 0; list[i]; i++)
 161                 out += scnprintf(out, buf + size - out,
 162                                 i == selected ? "[%s] " : "%s ", list[i]);
 163
 164         out[-1] = '\n';
 165         return out - buf;
 166 }
 167
 168 SHOW(__bch_cached_dev)
 169 {
 170         struct cached_dev *dc = container_of(kobj, struct cached_dev,
 171                                              disk.kobj);
 172         char const *states[] = { "no cache", "clean", "dirty", "inconsistent" };
 173         int wb = dc->writeback_running;
 174
 175 #define var(stat)               (dc->stat)
 176
 177         if (attr == &sysfs_cache_mode)
 178                 return bch_snprint_string_list(buf, PAGE_SIZE,
 179                                                bch_cache_modes,
 180                                                BDEV_CACHE_MODE(&dc->sb));
 181
 182         if (attr == &sysfs_readahead_cache_policy)
 183                 return bch_snprint_string_list(buf, PAGE_SIZE,
 184                                               bch_reada_cache_policies,
 185                                               dc->cache_readahead_policy);
 186
 187         if (attr == &sysfs_stop_when_cache_set_failed)
 188                 return bch_snprint_string_list(buf, PAGE_SIZE,
 189                                                bch_stop_on_failure_modes,
 190                                                dc->stop_when_cache_set_failed);
 191
 192
 193         sysfs_printf(data_csum,         "%i", dc->disk.data_csum);
 194         var_printf(verify,              "%i");
 195         var_printf(bypass_torture_test, "%i");
 196         var_printf(writeback_metadata,  "%i");
 197         var_printf(writeback_running,   "%i");
 198         var_print(writeback_delay);
 199         var_print(writeback_percent);
 200         sysfs_hprint(writeback_rate,
 201                      wb ? atomic_long_read(&dc->writeback_rate.rate) << 9 : 0);
 202         sysfs_printf(io_errors,         "%i", atomic_read(&dc->io_errors));
 203         sysfs_printf(io_error_limit,    "%i", dc->error_limit);
 204         sysfs_printf(io_disable,        "%i", dc->io_disable);
 205         var_print(writeback_rate_update_seconds);
 206         var_print(writeback_rate_i_term_inverse);
 207         var_print(writeback_rate_p_term_inverse);
 208         var_print(writeback_rate_minimum);
 209
 210         if (attr == &sysfs_writeback_rate_debug) {
 211                 char rate[20];
 212                 char dirty[20];
 213                 char target[20];
 214                 char proportional[20];
 215                 char integral[20];
 216                 char change[20];
 217                 s64 next_io;
 218
 219                 /*
 220                  * Except for dirty and target, other values should
 221                  * be 0 if writeback is not running.
 222                  */
 223                 bch_hprint(rate,
 224                            wb ? atomic_long_read(&dc->writeback_rate.rate) << 9
 225                               : 0);
 226                 bch_hprint(dirty, bcache_dev_sectors_dirty(&dc->disk) << 9);
 227                 bch_hprint(target, dc->writeback_rate_target << 9);
 228                 bch_hprint(proportional,
 229                            wb ? dc->writeback_rate_proportional << 9 : 0);
 230                 bch_hprint(integral,
 231                            wb ? dc->writeback_rate_integral_scaled << 9 : 0);
 232                 bch_hprint(change, wb ? dc->writeback_rate_change << 9 : 0);
 233                 next_io = wb ? div64_s64(dc->writeback_rate.next-local_clock(),
 234                                          NSEC_PER_MSEC) : 0;
 235
 236                 return sprintf(buf,
 237                                "rate:\t\t%s/sec\n"
 238                                "dirty:\t\t%s\n"
 239                                "target:\t\t%s\n"
 240                                "proportional:\t%s\n"
 241                                "integral:\t%s\n"
 242                                "change:\t\t%s/sec\n"
 243                                "next io:\t%llims\n",
 244                                rate, dirty, target, proportional,
 245                                integral, change, next_io);
 246         }
 247
 248         sysfs_hprint(dirty_data,
 249                      bcache_dev_sectors_dirty(&dc->disk) << 9);
 250
 251         sysfs_hprint(stripe_size,        ((uint64_t)dc->disk.stripe_size) << 9);
 252         var_printf(partial_stripes_expensive,   "%u");
 253
 254         var_hprint(sequential_cutoff);
 255         var_hprint(readahead);
 256
 257         sysfs_print(running,            atomic_read(&dc->running));
 258         sysfs_print(state,              states[BDEV_STATE(&dc->sb)]);
 259
 260         if (attr == &sysfs_label) {
 261                 memcpy(buf, dc->sb.label, SB_LABEL_SIZE);
 262                 buf[SB_LABEL_SIZE + 1] = '\0';
 263                 strcat(buf, "\n");
 264                 return strlen(buf);
 265         }
 266
 267         if (attr == &sysfs_backing_dev_name) {
 268                 snprintf(buf, BDEVNAME_SIZE + 1, "%s", dc->backing_dev_name);
 269                 strcat(buf, "\n");
 270                 return strlen(buf);
 271         }
 272
 273         if (attr == &sysfs_backing_dev_uuid) {
 274                 /* convert binary uuid into 36-byte string plus '\0' */
 275                 snprintf(buf, 36+1, "%pU", dc->sb.uuid);
 276                 strcat(buf, "\n");
 277                 return strlen(buf);
 278         }
 279
 280 #undef var
 281         return 0;
 282 }
 283 SHOW_LOCKED(bch_cached_dev)
 284
 285 STORE(__cached_dev)
 286 {
 287         struct cached_dev *dc = container_of(kobj, struct cached_dev,
 288                                              disk.kobj);
 289         ssize_t v;
 290         struct cache_set *c;
 291         struct kobj_uevent_env *env;
 292
 293         /* no user space access if system is rebooting */
 294         if (bcache_is_reboot)
 295                 return -EBUSY;
 296
 297 #define d_strtoul(var)          sysfs_strtoul(var, dc->var)
 298 #define d_strtoul_nonzero(var)  sysfs_strtoul_clamp(var, dc->var, 1, INT_MAX)
 299 #define d_strtoi_h(var)         sysfs_hatoi(var, dc->var)
 300
 301         sysfs_strtoul(data_csum,        dc->disk.data_csum);
 302         d_strtoul(verify);
 303         sysfs_strtoul_bool(bypass_torture_test, dc->bypass_torture_test);
 304         sysfs_strtoul_bool(writeback_metadata, dc->writeback_metadata);
 305         sysfs_strtoul_bool(writeback_running, dc->writeback_running);
 306         sysfs_strtoul_clamp(writeback_delay, dc->writeback_delay, 0, UINT_MAX);
 307
 308         sysfs_strtoul_clamp(writeback_percent, dc->writeback_percent,
 309                             0, bch_cutoff_writeback);
 310
 311         if (attr == &sysfs_writeback_rate) {
 312                 ssize_t ret;
 313                 long int v = atomic_long_read(&dc->writeback_rate.rate);
 314
 315                 ret = strtoul_safe_clamp(buf, v, 1, INT_MAX);
 316
 317                 if (!ret) {
 318                         atomic_long_set(&dc->writeback_rate.rate, v);
 319                         ret = size;
 320                 }
 321
 322                 return ret;
 323         }
 324
 325         sysfs_strtoul_clamp(writeback_rate_update_seconds,
 326                             dc->writeback_rate_update_seconds,
 327                             1, WRITEBACK_RATE_UPDATE_SECS_MAX);
 328         sysfs_strtoul_clamp(writeback_rate_i_term_inverse,
 329                             dc->writeback_rate_i_term_inverse,
 330                             1, UINT_MAX);
 331         sysfs_strtoul_clamp(writeback_rate_p_term_inverse,
 332                             dc->writeback_rate_p_term_inverse,
 333                             1, UINT_MAX);
 334         sysfs_strtoul_clamp(writeback_rate_minimum,
 335                             dc->writeback_rate_minimum,
 336                             1, UINT_MAX);
 337
 338         sysfs_strtoul_clamp(io_error_limit, dc->error_limit, 0, INT_MAX);
 339
 340         if (attr == &sysfs_io_disable) {
 341                 int v = strtoul_or_return(buf);
 342
 343                 dc->io_disable = v ? 1 : 0;
 344         }
 345
 346         sysfs_strtoul_clamp(sequential_cutoff,
 347                             dc->sequential_cutoff,
 348                             0, UINT_MAX);
 349         d_strtoi_h(readahead);
 350
 351         if (attr == &sysfs_clear_stats)
 352                 bch_cache_accounting_clear(&dc->accounting);
 353
 354         if (attr == &sysfs_running &&
 355             strtoul_or_return(buf)) {
 356                 v = bch_cached_dev_run(dc);
 357                 if (v)
 358                         return v;
 359         }
 360
 361         if (attr == &sysfs_cache_mode) {
 362                 v = __sysfs_match_string(bch_cache_modes, -1, buf);
 363                 if (v < 0)
 364                         return v;
 365
 366                 if ((unsigned int) v != BDEV_CACHE_MODE(&dc->sb)) {
 367                         SET_BDEV_CACHE_MODE(&dc->sb, v);
 368                         bch_write_bdev_super(dc, NULL);
 369                 }
 370         }
 371
 372         if (attr == &sysfs_readahead_cache_policy) {
 373                 v = __sysfs_match_string(bch_reada_cache_policies, -1, buf);
 374                 if (v < 0)
 375                         return v;
 376
 377                 if ((unsigned int) v != dc->cache_readahead_policy)
 378                         dc->cache_readahead_policy = v;
 379         }
 380
 381         if (attr == &sysfs_stop_when_cache_set_failed) {
 382                 v = __sysfs_match_string(bch_stop_on_failure_modes, -1, buf);
 383                 if (v < 0)
 384                         return v;
 385
 386                 dc->stop_when_cache_set_failed = v;
 387         }
 388
 389         if (attr == &sysfs_label) {
 390                 if (size > SB_LABEL_SIZE)
 391                         return -EINVAL;
 392                 memcpy(dc->sb.label, buf, size);
 393                 if (size < SB_LABEL_SIZE)
 394                         dc->sb.label[size] = '\0';
 395                 if (size && dc->sb.label[size - 1] == '\n')
 396                         dc->sb.label[size - 1] = '\0';
 397                 bch_write_bdev_super(dc, NULL);
 398                 if (dc->disk.c) {
 399                         memcpy(dc->disk.c->uuids[dc->disk.id].label,
 400                                buf, SB_LABEL_SIZE);
 401                         bch_uuid_write(dc->disk.c);
 402                 }
 403                 env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL);
 404                 if (!env)
 405                         return -ENOMEM;
 406                 add_uevent_var(env, "DRIVER=bcache");
 407                 add_uevent_var(env, "CACHED_UUID=%pU", dc->sb.uuid),
 408                 add_uevent_var(env, "CACHED_LABEL=%s", buf);
 409                 kobject_uevent_env(&disk_to_dev(dc->disk.disk)->kobj,
 410                                    KOBJ_CHANGE,
 411                                    env->envp);
 412                 kfree(env);
 413         }
 414
 415         if (attr == &sysfs_attach) {
 416                 uint8_t         set_uuid[16];
 417
 418                 if (bch_parse_uuid(buf, set_uuid) < 16)
 419                         return -EINVAL;
 420
 421                 v = -ENOENT;
 422                 list_for_each_entry(c, &bch_cache_sets, list) {
 423                         v = bch_cached_dev_attach(dc, c, set_uuid);
 424                         if (!v)
 425                                 return size;
 426                 }
 427                 if (v == -ENOENT)
 428                         pr_err("Can't attach %s: cache set not found\n", buf);
 429                 return v;
 430         }
 431
 432         if (attr == &sysfs_detach && dc->disk.c)
 433                 bch_cached_dev_detach(dc);
 434
 435         if (attr == &sysfs_stop)
 436                 bcache_device_stop(&dc->disk);
 437
 438         return size;
 439 }
 440
 441 STORE(bch_cached_dev)
 442 {
 443         struct cached_dev *dc = container_of(kobj, struct cached_dev,
 444                                              disk.kobj);
 445
 446         /* no user space access if system is rebooting */
 447         if (bcache_is_reboot)
 448                 return -EBUSY;
 449
 450         mutex_lock(&bch_register_lock);
 451         size = __cached_dev_store(kobj, attr, buf, size);
 452
 453         if (attr == &sysfs_writeback_running) {
 454                 /* dc->writeback_running changed in __cached_dev_store() */
 455                 if (IS_ERR_OR_NULL(dc->writeback_thread)) {
 456                         /*
 457                          * reject setting it to 1 via sysfs if writeback
 458                          * kthread is not created yet.
 459                          */
 460                         if (dc->writeback_running) {
 461                                 dc->writeback_running = false;
 462                                 pr_err("%s: failed to run non-existent writeback thread\n",
 463                                                 dc->disk.disk->disk_name);
 464                         }
 465                 } else
 466                         /*
 467                          * writeback kthread will check if dc->writeback_running
 468                          * is true or false.
 469                          */
 470                         bch_writeback_queue(dc);
 471         }
 472
 473         /*
 474          * Only set BCACHE_DEV_WB_RUNNING when cached device attached to
 475          * a cache set, otherwise it doesn't make sense.
 476          */
 477         if (attr == &sysfs_writeback_percent)
 478                 if ((dc->disk.c != NULL) &&
 479                     (!test_and_set_bit(BCACHE_DEV_WB_RUNNING, &dc->disk.flags)))
 480                         schedule_delayed_work(&dc->writeback_rate_update,
 481                                       dc->writeback_rate_update_seconds * HZ);
 482
 483         mutex_unlock(&bch_register_lock);
 484         return size;
 485 }
 486
 487 static struct attribute *bch_cached_dev_files[] = {
 488         &sysfs_attach,
 489         &sysfs_detach,
 490         &sysfs_stop,
 491 #if 0
 492         &sysfs_data_csum,
 493 #endif
 494         &sysfs_cache_mode,
 495         &sysfs_readahead_cache_policy,
 496         &sysfs_stop_when_cache_set_failed,
 497         &sysfs_writeback_metadata,
 498         &sysfs_writeback_running,
 499         &sysfs_writeback_delay,
 500         &sysfs_writeback_percent,
 501         &sysfs_writeback_rate,
 502         &sysfs_writeback_rate_update_seconds,
 503         &sysfs_writeback_rate_i_term_inverse,
 504         &sysfs_writeback_rate_p_term_inverse,
 505         &sysfs_writeback_rate_minimum,
 506         &sysfs_writeback_rate_debug,
 507         &sysfs_io_errors,
 508         &sysfs_io_error_limit,
 509         &sysfs_io_disable,
 510         &sysfs_dirty_data,
 511         &sysfs_stripe_size,
 512         &sysfs_partial_stripes_expensive,
 513         &sysfs_sequential_cutoff,
 514         &sysfs_clear_stats,
 515         &sysfs_running,
 516         &sysfs_state,
 517         &sysfs_label,
 518         &sysfs_readahead,
 519 #ifdef CONFIG_BCACHE_DEBUG
 520         &sysfs_verify,
 521         &sysfs_bypass_torture_test,
 522 #endif
 523         &sysfs_backing_dev_name,
 524         &sysfs_backing_dev_uuid,
 525         NULL
 526 };
 527 KTYPE(bch_cached_dev);
 528
 529 SHOW(bch_flash_dev)
 530 {
 531         struct bcache_device *d = container_of(kobj, struct bcache_device,
 532                                                kobj);
 533         struct uuid_entry *u = &d->c->uuids[d->id];
 534
 535         sysfs_printf(data_csum, "%i", d->data_csum);
 536         sysfs_hprint(size,      u->sectors << 9);
 537
 538         if (attr == &sysfs_label) {
 539                 memcpy(buf, u->label, SB_LABEL_SIZE);
 540                 buf[SB_LABEL_SIZE + 1] = '\0';
 541                 strcat(buf, "\n");
 542                 return strlen(buf);
 543         }
 544
 545         return 0;
 546 }
 547
 548 STORE(__bch_flash_dev)
 549 {
 550         struct bcache_device *d = container_of(kobj, struct bcache_device,
 551                                                kobj);
 552         struct uuid_entry *u = &d->c->uuids[d->id];
 553
 554         /* no user space access if system is rebooting */
 555         if (bcache_is_reboot)
 556                 return -EBUSY;
 557
 558         sysfs_strtoul(data_csum,        d->data_csum);
 559
 560         if (attr == &sysfs_size) {
 561                 uint64_t v;
 562
 563                 strtoi_h_or_return(buf, v);
 564
 565                 u->sectors = v >> 9;
 566                 bch_uuid_write(d->c);
 567                 set_capacity(d->disk, u->sectors);
 568         }
 569
 570         if (attr == &sysfs_label) {
 571                 memcpy(u->label, buf, SB_LABEL_SIZE);
 572                 bch_uuid_write(d->c);
 573         }
 574
 575         if (attr == &sysfs_unregister) {
 576                 set_bit(BCACHE_DEV_DETACHING, &d->flags);
 577                 bcache_device_stop(d);
 578         }
 579
 580         return size;
 581 }
 582 STORE_LOCKED(bch_flash_dev)
 583
 584 static struct attribute *bch_flash_dev_files[] = {
 585         &sysfs_unregister,
 586 #if 0
 587         &sysfs_data_csum,
 588 #endif
 589         &sysfs_label,
 590         &sysfs_size,
 591         NULL
 592 };
 593 KTYPE(bch_flash_dev);
 594
 595 struct bset_stats_op {
 596         struct btree_op op;
 597         size_t nodes;
 598         struct bset_stats stats;
 599 };
 600
 601 static int bch_btree_bset_stats(struct btree_op *b_op, struct btree *b)
 602 {
 603         struct bset_stats_op *op = container_of(b_op, struct bset_stats_op, op);
 604
 605         op->nodes++;
 606         bch_btree_keys_stats(&b->keys, &op->stats);
 607
 608         return MAP_CONTINUE;
 609 }
 610
 611 static int bch_bset_print_stats(struct cache_set *c, char *buf)
 612 {
 613         struct bset_stats_op op;
 614         int ret;
 615
 616         memset(&op, 0, sizeof(op));
 617         bch_btree_op_init(&op.op, -1);
 618
 619         ret = bch_btree_map_nodes(&op.op, c, &ZERO_KEY, bch_btree_bset_stats);
 620         if (ret < 0)
 621                 return ret;
 622
 623         return snprintf(buf, PAGE_SIZE,
 624                         "btree nodes:           %zu\n"
 625                         "written sets:          %zu\n"
 626                         "unwritten sets:                %zu\n"
 627                         "written key bytes:     %zu\n"
 628                         "unwritten key bytes:   %zu\n"
 629                         "floats:                        %zu\n"
 630                         "failed:                        %zu\n",
 631                         op.nodes,
 632                         op.stats.sets_written, op.stats.sets_unwritten,
 633                         op.stats.bytes_written, op.stats.bytes_unwritten,
 634                         op.stats.floats, op.stats.failed);
 635 }
 636
 637 static unsigned int bch_root_usage(struct cache_set *c)
 638 {
 639         unsigned int bytes = 0;
 640         struct bkey *k;
 641         struct btree *b;
 642         struct btree_iter iter;
 643
 644         goto lock_root;
 645
 646         do {
 647                 rw_unlock(false, b);
 648 lock_root:
 649                 b = c->root;
 650                 rw_lock(false, b, b->level);
 651         } while (b != c->root);
 652
 653         for_each_key_filter(&b->keys, k, &iter, bch_ptr_bad)
 654                 bytes += bkey_bytes(k);
 655
 656         rw_unlock(false, b);
 657
 658         return (bytes * 100) / btree_bytes(c);
 659 }
 660
 661 static size_t bch_cache_size(struct cache_set *c)
 662 {
 663         size_t ret = 0;
 664         struct btree *b;
 665
 666         mutex_lock(&c->bucket_lock);
 667         list_for_each_entry(b, &c->btree_cache, list)
 668                 ret += 1 << (b->keys.page_order + PAGE_SHIFT);
 669
 670         mutex_unlock(&c->bucket_lock);
 671         return ret;
 672 }
 673
 674 static unsigned int bch_cache_max_chain(struct cache_set *c)
 675 {
 676         unsigned int ret = 0;
 677         struct hlist_head *h;
 678
 679         mutex_lock(&c->bucket_lock);
 680
 681         for (h = c->bucket_hash;
 682              h < c->bucket_hash + (1 << BUCKET_HASH_BITS);
 683              h++) {
 684                 unsigned int i = 0;
 685                 struct hlist_node *p;
 686
 687                 hlist_for_each(p, h)
 688                         i++;
 689
 690                 ret = max(ret, i);
 691         }
 692
 693         mutex_unlock(&c->bucket_lock);
 694         return ret;
 695 }
 696
 697 static unsigned int bch_btree_used(struct cache_set *c)
 698 {
 699         return div64_u64(c->gc_stats.key_bytes * 100,
 700                          (c->gc_stats.nodes ?: 1) * btree_bytes(c));
 701 }
 702
 703 static unsigned int bch_average_key_size(struct cache_set *c)
 704 {
 705         return c->gc_stats.nkeys
 706                 ? div64_u64(c->gc_stats.data, c->gc_stats.nkeys)
 707                 : 0;
 708 }
 709
 710 SHOW(__bch_cache_set)
 711 {
 712         struct cache_set *c = container_of(kobj, struct cache_set, kobj);
 713
 714         sysfs_print(synchronous,                CACHE_SYNC(&c->cache->sb));
 715         sysfs_print(journal_delay_ms,           c->journal_delay_ms);
 716         sysfs_hprint(bucket_size,               bucket_bytes(c->cache));
 717         sysfs_hprint(block_size,                block_bytes(c->cache));
 718         sysfs_print(tree_depth,                 c->root->level);
 719         sysfs_print(root_usage_percent,         bch_root_usage(c));
 720
 721         sysfs_hprint(btree_cache_size,          bch_cache_size(c));
 722         sysfs_print(btree_cache_max_chain,      bch_cache_max_chain(c));
 723         sysfs_print(cache_available_percent,    100 - c->gc_stats.in_use);
 724
 725         sysfs_print_time_stats(&c->btree_gc_time,       btree_gc, sec, ms);
 726         sysfs_print_time_stats(&c->btree_split_time,    btree_split, sec, us);
 727         sysfs_print_time_stats(&c->sort.time,           btree_sort, ms, us);
 728         sysfs_print_time_stats(&c->btree_read_time,     btree_read, ms, us);
 729
 730         sysfs_print(btree_used_percent, bch_btree_used(c));
 731         sysfs_print(btree_nodes,        c->gc_stats.nodes);
 732         sysfs_hprint(average_key_size,  bch_average_key_size(c));
 733
 734         sysfs_print(cache_read_races,
 735                     atomic_long_read(&c->cache_read_races));
 736
 737         sysfs_print(reclaim,
 738                     atomic_long_read(&c->reclaim));
 739
 740         sysfs_print(reclaimed_journal_buckets,
 741                     atomic_long_read(&c->reclaimed_journal_buckets));
 742
 743         sysfs_print(flush_write,
 744                     atomic_long_read(&c->flush_write));
 745
 746         sysfs_print(writeback_keys_done,
 747                     atomic_long_read(&c->writeback_keys_done));
 748         sysfs_print(writeback_keys_failed,
 749                     atomic_long_read(&c->writeback_keys_failed));
 750
 751         if (attr == &sysfs_errors)
 752                 return bch_snprint_string_list(buf, PAGE_SIZE, error_actions,
 753                                                c->on_error);
 754
 755         /* See count_io_errors for why 88 */
 756         sysfs_print(io_error_halflife,  c->error_decay * 88);
 757         sysfs_print(io_error_limit,     c->error_limit);
 758
 759         sysfs_hprint(congested,
 760                      ((uint64_t) bch_get_congested(c)) << 9);
 761         sysfs_print(congested_read_threshold_us,
 762                     c->congested_read_threshold_us);
 763         sysfs_print(congested_write_threshold_us,
 764                     c->congested_write_threshold_us);
 765
 766         sysfs_print(cutoff_writeback, bch_cutoff_writeback);
 767         sysfs_print(cutoff_writeback_sync, bch_cutoff_writeback_sync);
 768
 769         sysfs_print(active_journal_entries,     fifo_used(&c->journal.pin));
 770         sysfs_printf(verify,                    "%i", c->verify);
 771         sysfs_printf(key_merging_disabled,      "%i", c->key_merging_disabled);
 772         sysfs_printf(expensive_debug_checks,
 773                      "%i", c->expensive_debug_checks);
 774         sysfs_printf(gc_always_rewrite,         "%i", c->gc_always_rewrite);
 775         sysfs_printf(btree_shrinker_disabled,   "%i", c->shrinker_disabled);
 776         sysfs_printf(copy_gc_enabled,           "%i", c->copy_gc_enabled);
 777         sysfs_printf(idle_max_writeback_rate,   "%i",
 778                      c->idle_max_writeback_rate_enabled);
 779         sysfs_printf(gc_after_writeback,        "%i", c->gc_after_writeback);
 780         sysfs_printf(io_disable,                "%i",
 781                      test_bit(CACHE_SET_IO_DISABLE, &c->flags));
 782
 783         if (attr == &sysfs_bset_tree_stats)
 784                 return bch_bset_print_stats(c, buf);
 785
 786         if (attr == &sysfs_feature_compat)
 787                 return bch_print_cache_set_feature_compat(c, buf, PAGE_SIZE);
 788         if (attr == &sysfs_feature_ro_compat)
 789                 return bch_print_cache_set_feature_ro_compat(c, buf, PAGE_SIZE);
 790         if (attr == &sysfs_feature_incompat)
 791                 return bch_print_cache_set_feature_incompat(c, buf, PAGE_SIZE);
 792
 793         return 0;
 794 }
 795 SHOW_LOCKED(bch_cache_set)
 796
 797 STORE(__bch_cache_set)
 798 {
 799         struct cache_set *c = container_of(kobj, struct cache_set, kobj);
 800         ssize_t v;
 801
 802         /* no user space access if system is rebooting */
 803         if (bcache_is_reboot)
 804                 return -EBUSY;
 805
 806         if (attr == &sysfs_unregister)
 807                 bch_cache_set_unregister(c);
 808
 809         if (attr == &sysfs_stop)
 810                 bch_cache_set_stop(c);
 811
 812         if (attr == &sysfs_synchronous) {
 813                 bool sync = strtoul_or_return(buf);
 814
 815                 if (sync != CACHE_SYNC(&c->cache->sb)) {
 816                         SET_CACHE_SYNC(&c->cache->sb, sync);
 817                         bcache_write_super(c);
 818                 }
 819         }
 820
 821         if (attr == &sysfs_flash_vol_create) {
 822                 int r;
 823                 uint64_t v;
 824
 825                 strtoi_h_or_return(buf, v);
 826
 827                 r = bch_flash_dev_create(c, v);
 828                 if (r)
 829                         return r;
 830         }
 831
 832         if (attr == &sysfs_clear_stats) {
 833                 atomic_long_set(&c->writeback_keys_done,        0);
 834                 atomic_long_set(&c->writeback_keys_failed,      0);
 835
 836                 memset(&c->gc_stats, 0, sizeof(struct gc_stat));
 837                 bch_cache_accounting_clear(&c->accounting);
 838         }
 839
 840         if (attr == &sysfs_trigger_gc)
 841                 force_wake_up_gc(c);
 842
 843         if (attr == &sysfs_prune_cache) {
 844                 struct shrink_control sc;
 845
 846                 sc.gfp_mask = GFP_KERNEL;
 847                 sc.nr_to_scan = strtoul_or_return(buf);
 848                 c->shrink.scan_objects(&c->shrink, &sc);
 849         }
 850
 851         sysfs_strtoul_clamp(congested_read_threshold_us,
 852                             c->congested_read_threshold_us,
 853                             0, UINT_MAX);
 854         sysfs_strtoul_clamp(congested_write_threshold_us,
 855                             c->congested_write_threshold_us,
 856                             0, UINT_MAX);
 857
 858         if (attr == &sysfs_errors) {
 859                 v = __sysfs_match_string(error_actions, -1, buf);
 860                 if (v < 0)
 861                         return v;
 862
 863                 c->on_error = v;
 864         }
 865
 866         sysfs_strtoul_clamp(io_error_limit, c->error_limit, 0, UINT_MAX);
 867
 868         /* See count_io_errors() for why 88 */
 869         if (attr == &sysfs_io_error_halflife) {
 870                 unsigned long v = 0;
 871                 ssize_t ret;
 872
 873                 ret = strtoul_safe_clamp(buf, v, 0, UINT_MAX);
 874                 if (!ret) {
 875                         c->error_decay = v / 88;
 876                         return size;
 877                 }
 878                 return ret;
 879         }
 880
 881         if (attr == &sysfs_io_disable) {
 882                 v = strtoul_or_return(buf);
 883                 if (v) {
 884                         if (test_and_set_bit(CACHE_SET_IO_DISABLE,
 885                                              &c->flags))
 886                                 pr_warn("CACHE_SET_IO_DISABLE already set\n");
 887                 } else {
 888                         if (!test_and_clear_bit(CACHE_SET_IO_DISABLE,
 889                                                 &c->flags))
 890                                 pr_warn("CACHE_SET_IO_DISABLE already cleared\n");
 891                 }
 892         }
 893
 894         sysfs_strtoul_clamp(journal_delay_ms,
 895                             c->journal_delay_ms,
 896                             0, USHRT_MAX);
 897         sysfs_strtoul_bool(verify,              c->verify);
 898         sysfs_strtoul_bool(key_merging_disabled, c->key_merging_disabled);
 899         sysfs_strtoul(expensive_debug_checks,   c->expensive_debug_checks);
 900         sysfs_strtoul_bool(gc_always_rewrite,   c->gc_always_rewrite);
 901         sysfs_strtoul_bool(btree_shrinker_disabled, c->shrinker_disabled);
 902         sysfs_strtoul_bool(copy_gc_enabled,     c->copy_gc_enabled);
 903         sysfs_strtoul_bool(idle_max_writeback_rate,
 904                            c->idle_max_writeback_rate_enabled);
 905
 906         /*
 907          * write gc_after_writeback here may overwrite an already set
 908          * BCH_DO_AUTO_GC, it doesn't matter because this flag will be
 909          * set in next chance.
 910          */
 911         sysfs_strtoul_clamp(gc_after_writeback, c->gc_after_writeback, 0, 1);
 912
 913         return size;
 914 }
 915 STORE_LOCKED(bch_cache_set)
 916
 917 SHOW(bch_cache_set_internal)
 918 {
 919         struct cache_set *c = container_of(kobj, struct cache_set, internal);
 920
 921         return bch_cache_set_show(&c->kobj, attr, buf);
 922 }
 923
 924 STORE(bch_cache_set_internal)
 925 {
 926         struct cache_set *c = container_of(kobj, struct cache_set, internal);
 927
 928         /* no user space access if system is rebooting */
 929         if (bcache_is_reboot)
 930                 return -EBUSY;
 931
 932         return bch_cache_set_store(&c->kobj, attr, buf, size);
 933 }
 934
 935 static void bch_cache_set_internal_release(struct kobject *k)
 936 {
 937 }
 938
 939 static struct attribute *bch_cache_set_files[] = {
 940         &sysfs_unregister,
 941         &sysfs_stop,
 942         &sysfs_synchronous,
 943         &sysfs_journal_delay_ms,
 944         &sysfs_flash_vol_create,
 945
 946         &sysfs_bucket_size,
 947         &sysfs_block_size,
 948         &sysfs_tree_depth,
 949         &sysfs_root_usage_percent,
 950         &sysfs_btree_cache_size,
 951         &sysfs_cache_available_percent,
 952
 953         &sysfs_average_key_size,
 954
 955         &sysfs_errors,
 956         &sysfs_io_error_limit,
 957         &sysfs_io_error_halflife,
 958         &sysfs_congested,
 959         &sysfs_congested_read_threshold_us,
 960         &sysfs_congested_write_threshold_us,
 961         &sysfs_clear_stats,
 962         NULL
 963 };
 964 KTYPE(bch_cache_set);
 965
 966 static struct attribute *bch_cache_set_internal_files[] = {
 967         &sysfs_active_journal_entries,
 968
 969         sysfs_time_stats_attribute_list(btree_gc, sec, ms)
 970         sysfs_time_stats_attribute_list(btree_split, sec, us)
 971         sysfs_time_stats_attribute_list(btree_sort, ms, us)
 972         sysfs_time_stats_attribute_list(btree_read, ms, us)
 973
 974         &sysfs_btree_nodes,
 975         &sysfs_btree_used_percent,
 976         &sysfs_btree_cache_max_chain,
 977
 978         &sysfs_bset_tree_stats,
 979         &sysfs_cache_read_races,
 980         &sysfs_reclaim,
 981         &sysfs_reclaimed_journal_buckets,
 982         &sysfs_flush_write,
 983         &sysfs_writeback_keys_done,
 984         &sysfs_writeback_keys_failed,
 985
 986         &sysfs_trigger_gc,
 987         &sysfs_prune_cache,
 988 #ifdef CONFIG_BCACHE_DEBUG
 989         &sysfs_verify,
 990         &sysfs_key_merging_disabled,
 991         &sysfs_expensive_debug_checks,
 992 #endif
 993         &sysfs_gc_always_rewrite,
 994         &sysfs_btree_shrinker_disabled,
 995         &sysfs_copy_gc_enabled,
 996         &sysfs_idle_max_writeback_rate,
 997         &sysfs_gc_after_writeback,
 998         &sysfs_io_disable,
 999         &sysfs_cutoff_writeback,
1000         &sysfs_cutoff_writeback_sync,
1001         &sysfs_feature_compat,
1002         &sysfs_feature_ro_compat,
1003         &sysfs_feature_incompat,
1004         NULL
1005 };
1006 KTYPE(bch_cache_set_internal);
1007
1008 static int __bch_cache_cmp(const void *l, const void *r)
1009 {
1010         cond_resched();
1011         return *((uint16_t *)r) - *((uint16_t *)l);
1012 }
1013
1014 SHOW(__bch_cache)
1015 {
1016         struct cache *ca = container_of(kobj, struct cache, kobj);
1017
1018         sysfs_hprint(bucket_size,       bucket_bytes(ca));
1019         sysfs_hprint(block_size,        block_bytes(ca));
1020         sysfs_print(nbuckets,           ca->sb.nbuckets);
1021         sysfs_print(discard,            ca->discard);
1022         sysfs_hprint(written, atomic_long_read(&ca->sectors_written) << 9);
1023         sysfs_hprint(btree_written,
1024                      atomic_long_read(&ca->btree_sectors_written) << 9);
1025         sysfs_hprint(metadata_written,
1026                      (atomic_long_read(&ca->meta_sectors_written) +
1027                       atomic_long_read(&ca->btree_sectors_written)) << 9);
1028
1029         sysfs_print(io_errors,
1030                     atomic_read(&ca->io_errors) >> IO_ERROR_SHIFT);
1031
1032         if (attr == &sysfs_cache_replacement_policy)
1033                 return bch_snprint_string_list(buf, PAGE_SIZE,
1034                                                cache_replacement_policies,
1035                                                CACHE_REPLACEMENT(&ca->sb));
1036
1037         if (attr == &sysfs_priority_stats) {
1038                 struct bucket *b;
1039                 size_t n = ca->sb.nbuckets, i;
1040                 size_t unused = 0, available = 0, dirty = 0, meta = 0;
1041                 uint64_t sum = 0;
1042                 /* Compute 31 quantiles */
1043                 uint16_t q[31], *p, *cached;
1044                 ssize_t ret;
1045
1046                 cached = p = vmalloc(array_size(sizeof(uint16_t),
1047                                                 ca->sb.nbuckets));
1048                 if (!p)
1049                         return -ENOMEM;
1050
1051                 mutex_lock(&ca->set->bucket_lock);
1052                 for_each_bucket(b, ca) {
1053                         if (!GC_SECTORS_USED(b))
1054                                 unused++;
1055                         if (GC_MARK(b) == GC_MARK_RECLAIMABLE)
1056                                 available++;
1057                         if (GC_MARK(b) == GC_MARK_DIRTY)
1058                                 dirty++;
1059                         if (GC_MARK(b) == GC_MARK_METADATA)
1060                                 meta++;
1061                 }
1062
1063                 for (i = ca->sb.first_bucket; i < n; i++)
1064                         p[i] = ca->buckets[i].prio;
1065                 mutex_unlock(&ca->set->bucket_lock);
1066
1067                 sort(p, n, sizeof(uint16_t), __bch_cache_cmp, NULL);
1068
1069                 while (n &&
1070                        !cached[n - 1])
1071                         --n;
1072
1073                 while (cached < p + n &&
1074                        *cached == BTREE_PRIO)
1075                         cached++, n--;
1076
1077                 for (i = 0; i < n; i++)
1078                         sum += INITIAL_PRIO - cached[i];
1079
1080                 if (n)
1081                         sum = div64_u64(sum, n);
1082
1083                 for (i = 0; i < ARRAY_SIZE(q); i++)
1084                         q[i] = INITIAL_PRIO - cached[n * (i + 1) /
1085                                 (ARRAY_SIZE(q) + 1)];
1086
1087                 vfree(p);
1088
1089                 ret = scnprintf(buf, PAGE_SIZE,
1090                                 "Unused:                %zu%%\n"
1091                                 "Clean:         %zu%%\n"
1092                                 "Dirty:         %zu%%\n"
1093                                 "Metadata:      %zu%%\n"
1094                                 "Average:       %llu\n"
1095                                 "Sectors per Q: %zu\n"
1096                                 "Quantiles:     [",
1097                                 unused * 100 / (size_t) ca->sb.nbuckets,
1098                                 available * 100 / (size_t) ca->sb.nbuckets,
1099                                 dirty * 100 / (size_t) ca->sb.nbuckets,
1100                                 meta * 100 / (size_t) ca->sb.nbuckets, sum,
1101                                 n * ca->sb.bucket_size / (ARRAY_SIZE(q) + 1));
1102
1103                 for (i = 0; i < ARRAY_SIZE(q); i++)
1104                         ret += scnprintf(buf + ret, PAGE_SIZE - ret,
1105                                          "%u ", q[i]);
1106                 ret--;
1107
1108                 ret += scnprintf(buf + ret, PAGE_SIZE - ret, "]\n");
1109
1110                 return ret;
1111         }
1112
1113         return 0;
1114 }
1115 SHOW_LOCKED(bch_cache)
1116
1117 STORE(__bch_cache)
1118 {
1119         struct cache *ca = container_of(kobj, struct cache, kobj);
1120         ssize_t v;
1121
1122         /* no user space access if system is rebooting */
1123         if (bcache_is_reboot)
1124                 return -EBUSY;
1125
1126         if (attr == &sysfs_discard) {
1127                 bool v = strtoul_or_return(buf);
1128
1129                 if (blk_queue_discard(bdev_get_queue(ca->bdev)))
1130                         ca->discard = v;
1131
1132                 if (v != CACHE_DISCARD(&ca->sb)) {
1133                         SET_CACHE_DISCARD(&ca->sb, v);
1134                         bcache_write_super(ca->set);
1135                 }
1136         }
1137
1138         if (attr == &sysfs_cache_replacement_policy) {
1139                 v = __sysfs_match_string(cache_replacement_policies, -1, buf);
1140                 if (v < 0)
1141                         return v;
1142
1143                 if ((unsigned int) v != CACHE_REPLACEMENT(&ca->sb)) {
1144                         mutex_lock(&ca->set->bucket_lock);
1145                         SET_CACHE_REPLACEMENT(&ca->sb, v);
1146                         mutex_unlock(&ca->set->bucket_lock);
1147
1148                         bcache_write_super(ca->set);
1149                 }
1150         }
1151
1152         if (attr == &sysfs_clear_stats) {
1153                 atomic_long_set(&ca->sectors_written, 0);
1154                 atomic_long_set(&ca->btree_sectors_written, 0);
1155                 atomic_long_set(&ca->meta_sectors_written, 0);
1156                 atomic_set(&ca->io_count, 0);
1157                 atomic_set(&ca->io_errors, 0);
1158         }
1159
1160         return size;
1161 }
1162 STORE_LOCKED(bch_cache)
1163
1164 static struct attribute *bch_cache_files[] = {
1165         &sysfs_bucket_size,
1166         &sysfs_block_size,
1167         &sysfs_nbuckets,
1168         &sysfs_priority_stats,
1169         &sysfs_discard,
1170         &sysfs_written,
1171         &sysfs_btree_written,
1172         &sysfs_metadata_written,
1173         &sysfs_io_errors,
1174         &sysfs_clear_stats,
1175         &sysfs_cache_replacement_policy,
1176         NULL
1177 };
1178 KTYPE(bch_cache);