linux/drivers/md/bcache/sysfs.c
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   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
  20extern bool bcache_is_reboot;
  21
  22/* Default is 0 ("writethrough") */
  23static const char * const bch_cache_modes[] = {
  24        "writethrough",
  25        "writeback",
  26        "writearound",
  27        "none",
  28        NULL
  29};
  30
  31static const char * const bch_reada_cache_policies[] = {
  32        "all",
  33        "meta-only",
  34        NULL
  35};
  36
  37/* Default is 0 ("auto") */
  38static const char * const bch_stop_on_failure_modes[] = {
  39        "auto",
  40        "always",
  41        NULL
  42};
  43
  44static const char * const cache_replacement_policies[] = {
  45        "lru",
  46        "fifo",
  47        "random",
  48        NULL
  49};
  50
  51static const char * const error_actions[] = {
  52        "unregister",
  53        "panic",
  54        NULL
  55};
  56
  57write_attribute(attach);
  58write_attribute(detach);
  59write_attribute(unregister);
  60write_attribute(stop);
  61write_attribute(clear_stats);
  62write_attribute(trigger_gc);
  63write_attribute(prune_cache);
  64write_attribute(flash_vol_create);
  65
  66read_attribute(bucket_size);
  67read_attribute(block_size);
  68read_attribute(nbuckets);
  69read_attribute(tree_depth);
  70read_attribute(root_usage_percent);
  71read_attribute(priority_stats);
  72read_attribute(btree_cache_size);
  73read_attribute(btree_cache_max_chain);
  74read_attribute(cache_available_percent);
  75read_attribute(written);
  76read_attribute(btree_written);
  77read_attribute(metadata_written);
  78read_attribute(active_journal_entries);
  79read_attribute(backing_dev_name);
  80read_attribute(backing_dev_uuid);
  81
  82sysfs_time_stats_attribute(btree_gc,    sec, ms);
  83sysfs_time_stats_attribute(btree_split, sec, us);
  84sysfs_time_stats_attribute(btree_sort,  ms,  us);
  85sysfs_time_stats_attribute(btree_read,  ms,  us);
  86
  87read_attribute(btree_nodes);
  88read_attribute(btree_used_percent);
  89read_attribute(average_key_size);
  90read_attribute(dirty_data);
  91read_attribute(bset_tree_stats);
  92read_attribute(feature_compat);
  93read_attribute(feature_ro_compat);
  94read_attribute(feature_incompat);
  95
  96read_attribute(state);
  97read_attribute(cache_read_races);
  98read_attribute(reclaim);
  99read_attribute(reclaimed_journal_buckets);
 100read_attribute(flush_write);
 101read_attribute(writeback_keys_done);
 102read_attribute(writeback_keys_failed);
 103read_attribute(io_errors);
 104read_attribute(congested);
 105read_attribute(cutoff_writeback);
 106read_attribute(cutoff_writeback_sync);
 107rw_attribute(congested_read_threshold_us);
 108rw_attribute(congested_write_threshold_us);
 109
 110rw_attribute(sequential_cutoff);
 111rw_attribute(data_csum);
 112rw_attribute(cache_mode);
 113rw_attribute(readahead_cache_policy);
 114rw_attribute(stop_when_cache_set_failed);
 115rw_attribute(writeback_metadata);
 116rw_attribute(writeback_running);
 117rw_attribute(writeback_percent);
 118rw_attribute(writeback_delay);
 119rw_attribute(writeback_rate);
 120rw_attribute(writeback_consider_fragment);
 121
 122rw_attribute(writeback_rate_update_seconds);
 123rw_attribute(writeback_rate_i_term_inverse);
 124rw_attribute(writeback_rate_p_term_inverse);
 125rw_attribute(writeback_rate_fp_term_low);
 126rw_attribute(writeback_rate_fp_term_mid);
 127rw_attribute(writeback_rate_fp_term_high);
 128rw_attribute(writeback_rate_minimum);
 129read_attribute(writeback_rate_debug);
 130
 131read_attribute(stripe_size);
 132read_attribute(partial_stripes_expensive);
 133
 134rw_attribute(synchronous);
 135rw_attribute(journal_delay_ms);
 136rw_attribute(io_disable);
 137rw_attribute(discard);
 138rw_attribute(running);
 139rw_attribute(label);
 140rw_attribute(errors);
 141rw_attribute(io_error_limit);
 142rw_attribute(io_error_halflife);
 143rw_attribute(verify);
 144rw_attribute(bypass_torture_test);
 145rw_attribute(key_merging_disabled);
 146rw_attribute(gc_always_rewrite);
 147rw_attribute(expensive_debug_checks);
 148rw_attribute(cache_replacement_policy);
 149rw_attribute(btree_shrinker_disabled);
 150rw_attribute(copy_gc_enabled);
 151rw_attribute(idle_max_writeback_rate);
 152rw_attribute(gc_after_writeback);
 153rw_attribute(size);
 154
 155static ssize_t bch_snprint_string_list(char *buf,
 156                                       size_t size,
 157                                       const char * const list[],
 158                                       size_t selected)
 159{
 160        char *out = buf;
 161        size_t i;
 162
 163        for (i = 0; list[i]; i++)
 164                out += scnprintf(out, buf + size - out,
 165                                i == selected ? "[%s] " : "%s ", list[i]);
 166
 167        out[-1] = '\n';
 168        return out - buf;
 169}
 170
 171SHOW(__bch_cached_dev)
 172{
 173        struct cached_dev *dc = container_of(kobj, struct cached_dev,
 174                                             disk.kobj);
 175        char const *states[] = { "no cache", "clean", "dirty", "inconsistent" };
 176        int wb = dc->writeback_running;
 177
 178#define var(stat)               (dc->stat)
 179
 180        if (attr == &sysfs_cache_mode)
 181                return bch_snprint_string_list(buf, PAGE_SIZE,
 182                                               bch_cache_modes,
 183                                               BDEV_CACHE_MODE(&dc->sb));
 184
 185        if (attr == &sysfs_readahead_cache_policy)
 186                return bch_snprint_string_list(buf, PAGE_SIZE,
 187                                              bch_reada_cache_policies,
 188                                              dc->cache_readahead_policy);
 189
 190        if (attr == &sysfs_stop_when_cache_set_failed)
 191                return bch_snprint_string_list(buf, PAGE_SIZE,
 192                                               bch_stop_on_failure_modes,
 193                                               dc->stop_when_cache_set_failed);
 194
 195
 196        sysfs_printf(data_csum,         "%i", dc->disk.data_csum);
 197        var_printf(verify,              "%i");
 198        var_printf(bypass_torture_test, "%i");
 199        var_printf(writeback_metadata,  "%i");
 200        var_printf(writeback_running,   "%i");
 201        var_printf(writeback_consider_fragment, "%i");
 202        var_print(writeback_delay);
 203        var_print(writeback_percent);
 204        sysfs_hprint(writeback_rate,
 205                     wb ? atomic_long_read(&dc->writeback_rate.rate) << 9 : 0);
 206        sysfs_printf(io_errors,         "%i", atomic_read(&dc->io_errors));
 207        sysfs_printf(io_error_limit,    "%i", dc->error_limit);
 208        sysfs_printf(io_disable,        "%i", dc->io_disable);
 209        var_print(writeback_rate_update_seconds);
 210        var_print(writeback_rate_i_term_inverse);
 211        var_print(writeback_rate_p_term_inverse);
 212        var_print(writeback_rate_fp_term_low);
 213        var_print(writeback_rate_fp_term_mid);
 214        var_print(writeback_rate_fp_term_high);
 215        var_print(writeback_rate_minimum);
 216
 217        if (attr == &sysfs_writeback_rate_debug) {
 218                char rate[20];
 219                char dirty[20];
 220                char target[20];
 221                char proportional[20];
 222                char integral[20];
 223                char change[20];
 224                s64 next_io;
 225
 226                /*
 227                 * Except for dirty and target, other values should
 228                 * be 0 if writeback is not running.
 229                 */
 230                bch_hprint(rate,
 231                           wb ? atomic_long_read(&dc->writeback_rate.rate) << 9
 232                              : 0);
 233                bch_hprint(dirty, bcache_dev_sectors_dirty(&dc->disk) << 9);
 234                bch_hprint(target, dc->writeback_rate_target << 9);
 235                bch_hprint(proportional,
 236                           wb ? dc->writeback_rate_proportional << 9 : 0);
 237                bch_hprint(integral,
 238                           wb ? dc->writeback_rate_integral_scaled << 9 : 0);
 239                bch_hprint(change, wb ? dc->writeback_rate_change << 9 : 0);
 240                next_io = wb ? div64_s64(dc->writeback_rate.next-local_clock(),
 241                                         NSEC_PER_MSEC) : 0;
 242
 243                return sprintf(buf,
 244                               "rate:\t\t%s/sec\n"
 245                               "dirty:\t\t%s\n"
 246                               "target:\t\t%s\n"
 247                               "proportional:\t%s\n"
 248                               "integral:\t%s\n"
 249                               "change:\t\t%s/sec\n"
 250                               "next io:\t%llims\n",
 251                               rate, dirty, target, proportional,
 252                               integral, change, next_io);
 253        }
 254
 255        sysfs_hprint(dirty_data,
 256                     bcache_dev_sectors_dirty(&dc->disk) << 9);
 257
 258        sysfs_hprint(stripe_size,        ((uint64_t)dc->disk.stripe_size) << 9);
 259        var_printf(partial_stripes_expensive,   "%u");
 260
 261        var_hprint(sequential_cutoff);
 262
 263        sysfs_print(running,            atomic_read(&dc->running));
 264        sysfs_print(state,              states[BDEV_STATE(&dc->sb)]);
 265
 266        if (attr == &sysfs_label) {
 267                memcpy(buf, dc->sb.label, SB_LABEL_SIZE);
 268                buf[SB_LABEL_SIZE + 1] = '\0';
 269                strcat(buf, "\n");
 270                return strlen(buf);
 271        }
 272
 273        if (attr == &sysfs_backing_dev_name) {
 274                snprintf(buf, BDEVNAME_SIZE + 1, "%s", dc->backing_dev_name);
 275                strcat(buf, "\n");
 276                return strlen(buf);
 277        }
 278
 279        if (attr == &sysfs_backing_dev_uuid) {
 280                /* convert binary uuid into 36-byte string plus '\0' */
 281                snprintf(buf, 36+1, "%pU", dc->sb.uuid);
 282                strcat(buf, "\n");
 283                return strlen(buf);
 284        }
 285
 286#undef var
 287        return 0;
 288}
 289SHOW_LOCKED(bch_cached_dev)
 290
 291STORE(__cached_dev)
 292{
 293        struct cached_dev *dc = container_of(kobj, struct cached_dev,
 294                                             disk.kobj);
 295        ssize_t v;
 296        struct cache_set *c;
 297        struct kobj_uevent_env *env;
 298
 299        /* no user space access if system is rebooting */
 300        if (bcache_is_reboot)
 301                return -EBUSY;
 302
 303#define d_strtoul(var)          sysfs_strtoul(var, dc->var)
 304#define d_strtoul_nonzero(var)  sysfs_strtoul_clamp(var, dc->var, 1, INT_MAX)
 305#define d_strtoi_h(var)         sysfs_hatoi(var, dc->var)
 306
 307        sysfs_strtoul(data_csum,        dc->disk.data_csum);
 308        d_strtoul(verify);
 309        sysfs_strtoul_bool(bypass_torture_test, dc->bypass_torture_test);
 310        sysfs_strtoul_bool(writeback_metadata, dc->writeback_metadata);
 311        sysfs_strtoul_bool(writeback_running, dc->writeback_running);
 312        sysfs_strtoul_bool(writeback_consider_fragment, dc->writeback_consider_fragment);
 313        sysfs_strtoul_clamp(writeback_delay, dc->writeback_delay, 0, UINT_MAX);
 314
 315        sysfs_strtoul_clamp(writeback_percent, dc->writeback_percent,
 316                            0, bch_cutoff_writeback);
 317
 318        if (attr == &sysfs_writeback_rate) {
 319                ssize_t ret;
 320                long int v = atomic_long_read(&dc->writeback_rate.rate);
 321
 322                ret = strtoul_safe_clamp(buf, v, 1, INT_MAX);
 323
 324                if (!ret) {
 325                        atomic_long_set(&dc->writeback_rate.rate, v);
 326                        ret = size;
 327                }
 328
 329                return ret;
 330        }
 331
 332        sysfs_strtoul_clamp(writeback_rate_update_seconds,
 333                            dc->writeback_rate_update_seconds,
 334                            1, WRITEBACK_RATE_UPDATE_SECS_MAX);
 335        sysfs_strtoul_clamp(writeback_rate_i_term_inverse,
 336                            dc->writeback_rate_i_term_inverse,
 337                            1, UINT_MAX);
 338        sysfs_strtoul_clamp(writeback_rate_p_term_inverse,
 339                            dc->writeback_rate_p_term_inverse,
 340                            1, UINT_MAX);
 341        sysfs_strtoul_clamp(writeback_rate_fp_term_low,
 342                            dc->writeback_rate_fp_term_low,
 343                            1, dc->writeback_rate_fp_term_mid - 1);
 344        sysfs_strtoul_clamp(writeback_rate_fp_term_mid,
 345                            dc->writeback_rate_fp_term_mid,
 346                            dc->writeback_rate_fp_term_low + 1,
 347                            dc->writeback_rate_fp_term_high - 1);
 348        sysfs_strtoul_clamp(writeback_rate_fp_term_high,
 349                            dc->writeback_rate_fp_term_high,
 350                            dc->writeback_rate_fp_term_mid + 1, UINT_MAX);
 351        sysfs_strtoul_clamp(writeback_rate_minimum,
 352                            dc->writeback_rate_minimum,
 353                            1, UINT_MAX);
 354
 355        sysfs_strtoul_clamp(io_error_limit, dc->error_limit, 0, INT_MAX);
 356
 357        if (attr == &sysfs_io_disable) {
 358                int v = strtoul_or_return(buf);
 359
 360                dc->io_disable = v ? 1 : 0;
 361        }
 362
 363        sysfs_strtoul_clamp(sequential_cutoff,
 364                            dc->sequential_cutoff,
 365                            0, UINT_MAX);
 366
 367        if (attr == &sysfs_clear_stats)
 368                bch_cache_accounting_clear(&dc->accounting);
 369
 370        if (attr == &sysfs_running &&
 371            strtoul_or_return(buf)) {
 372                v = bch_cached_dev_run(dc);
 373                if (v)
 374                        return v;
 375        }
 376
 377        if (attr == &sysfs_cache_mode) {
 378                v = __sysfs_match_string(bch_cache_modes, -1, buf);
 379                if (v < 0)
 380                        return v;
 381
 382                if ((unsigned int) v != BDEV_CACHE_MODE(&dc->sb)) {
 383                        SET_BDEV_CACHE_MODE(&dc->sb, v);
 384                        bch_write_bdev_super(dc, NULL);
 385                }
 386        }
 387
 388        if (attr == &sysfs_readahead_cache_policy) {
 389                v = __sysfs_match_string(bch_reada_cache_policies, -1, buf);
 390                if (v < 0)
 391                        return v;
 392
 393                if ((unsigned int) v != dc->cache_readahead_policy)
 394                        dc->cache_readahead_policy = v;
 395        }
 396
 397        if (attr == &sysfs_stop_when_cache_set_failed) {
 398                v = __sysfs_match_string(bch_stop_on_failure_modes, -1, buf);
 399                if (v < 0)
 400                        return v;
 401
 402                dc->stop_when_cache_set_failed = v;
 403        }
 404
 405        if (attr == &sysfs_label) {
 406                if (size > SB_LABEL_SIZE)
 407                        return -EINVAL;
 408                memcpy(dc->sb.label, buf, size);
 409                if (size < SB_LABEL_SIZE)
 410                        dc->sb.label[size] = '\0';
 411                if (size && dc->sb.label[size - 1] == '\n')
 412                        dc->sb.label[size - 1] = '\0';
 413                bch_write_bdev_super(dc, NULL);
 414                if (dc->disk.c) {
 415                        memcpy(dc->disk.c->uuids[dc->disk.id].label,
 416                               buf, SB_LABEL_SIZE);
 417                        bch_uuid_write(dc->disk.c);
 418                }
 419                env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL);
 420                if (!env)
 421                        return -ENOMEM;
 422                add_uevent_var(env, "DRIVER=bcache");
 423                add_uevent_var(env, "CACHED_UUID=%pU", dc->sb.uuid);
 424                add_uevent_var(env, "CACHED_LABEL=%s", buf);
 425                kobject_uevent_env(&disk_to_dev(dc->disk.disk)->kobj,
 426                                   KOBJ_CHANGE,
 427                                   env->envp);
 428                kfree(env);
 429        }
 430
 431        if (attr == &sysfs_attach) {
 432                uint8_t         set_uuid[16];
 433
 434                if (bch_parse_uuid(buf, set_uuid) < 16)
 435                        return -EINVAL;
 436
 437                v = -ENOENT;
 438                list_for_each_entry(c, &bch_cache_sets, list) {
 439                        v = bch_cached_dev_attach(dc, c, set_uuid);
 440                        if (!v)
 441                                return size;
 442                }
 443                if (v == -ENOENT)
 444                        pr_err("Can't attach %s: cache set not found\n", buf);
 445                return v;
 446        }
 447
 448        if (attr == &sysfs_detach && dc->disk.c)
 449                bch_cached_dev_detach(dc);
 450
 451        if (attr == &sysfs_stop)
 452                bcache_device_stop(&dc->disk);
 453
 454        return size;
 455}
 456
 457STORE(bch_cached_dev)
 458{
 459        struct cached_dev *dc = container_of(kobj, struct cached_dev,
 460                                             disk.kobj);
 461
 462        /* no user space access if system is rebooting */
 463        if (bcache_is_reboot)
 464                return -EBUSY;
 465
 466        mutex_lock(&bch_register_lock);
 467        size = __cached_dev_store(kobj, attr, buf, size);
 468
 469        if (attr == &sysfs_writeback_running) {
 470                /* dc->writeback_running changed in __cached_dev_store() */
 471                if (IS_ERR_OR_NULL(dc->writeback_thread)) {
 472                        /*
 473                         * reject setting it to 1 via sysfs if writeback
 474                         * kthread is not created yet.
 475                         */
 476                        if (dc->writeback_running) {
 477                                dc->writeback_running = false;
 478                                pr_err("%s: failed to run non-existent writeback thread\n",
 479                                                dc->disk.disk->disk_name);
 480                        }
 481                } else
 482                        /*
 483                         * writeback kthread will check if dc->writeback_running
 484                         * is true or false.
 485                         */
 486                        bch_writeback_queue(dc);
 487        }
 488
 489        /*
 490         * Only set BCACHE_DEV_WB_RUNNING when cached device attached to
 491         * a cache set, otherwise it doesn't make sense.
 492         */
 493        if (attr == &sysfs_writeback_percent)
 494                if ((dc->disk.c != NULL) &&
 495                    (!test_and_set_bit(BCACHE_DEV_WB_RUNNING, &dc->disk.flags)))
 496                        schedule_delayed_work(&dc->writeback_rate_update,
 497                                      dc->writeback_rate_update_seconds * HZ);
 498
 499        mutex_unlock(&bch_register_lock);
 500        return size;
 501}
 502
 503static struct attribute *bch_cached_dev_files[] = {
 504        &sysfs_attach,
 505        &sysfs_detach,
 506        &sysfs_stop,
 507#if 0
 508        &sysfs_data_csum,
 509#endif
 510        &sysfs_cache_mode,
 511        &sysfs_readahead_cache_policy,
 512        &sysfs_stop_when_cache_set_failed,
 513        &sysfs_writeback_metadata,
 514        &sysfs_writeback_running,
 515        &sysfs_writeback_delay,
 516        &sysfs_writeback_percent,
 517        &sysfs_writeback_rate,
 518        &sysfs_writeback_consider_fragment,
 519        &sysfs_writeback_rate_update_seconds,
 520        &sysfs_writeback_rate_i_term_inverse,
 521        &sysfs_writeback_rate_p_term_inverse,
 522        &sysfs_writeback_rate_fp_term_low,
 523        &sysfs_writeback_rate_fp_term_mid,
 524        &sysfs_writeback_rate_fp_term_high,
 525        &sysfs_writeback_rate_minimum,
 526        &sysfs_writeback_rate_debug,
 527        &sysfs_io_errors,
 528        &sysfs_io_error_limit,
 529        &sysfs_io_disable,
 530        &sysfs_dirty_data,
 531        &sysfs_stripe_size,
 532        &sysfs_partial_stripes_expensive,
 533        &sysfs_sequential_cutoff,
 534        &sysfs_clear_stats,
 535        &sysfs_running,
 536        &sysfs_state,
 537        &sysfs_label,
 538#ifdef CONFIG_BCACHE_DEBUG
 539        &sysfs_verify,
 540        &sysfs_bypass_torture_test,
 541#endif
 542        &sysfs_backing_dev_name,
 543        &sysfs_backing_dev_uuid,
 544        NULL
 545};
 546KTYPE(bch_cached_dev);
 547
 548SHOW(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        sysfs_printf(data_csum, "%i", d->data_csum);
 555        sysfs_hprint(size,      u->sectors << 9);
 556
 557        if (attr == &sysfs_label) {
 558                memcpy(buf, u->label, SB_LABEL_SIZE);
 559                buf[SB_LABEL_SIZE + 1] = '\0';
 560                strcat(buf, "\n");
 561                return strlen(buf);
 562        }
 563
 564        return 0;
 565}
 566
 567STORE(__bch_flash_dev)
 568{
 569        struct bcache_device *d = container_of(kobj, struct bcache_device,
 570                                               kobj);
 571        struct uuid_entry *u = &d->c->uuids[d->id];
 572
 573        /* no user space access if system is rebooting */
 574        if (bcache_is_reboot)
 575                return -EBUSY;
 576
 577        sysfs_strtoul(data_csum,        d->data_csum);
 578
 579        if (attr == &sysfs_size) {
 580                uint64_t v;
 581
 582                strtoi_h_or_return(buf, v);
 583
 584                u->sectors = v >> 9;
 585                bch_uuid_write(d->c);
 586                set_capacity(d->disk, u->sectors);
 587        }
 588
 589        if (attr == &sysfs_label) {
 590                memcpy(u->label, buf, SB_LABEL_SIZE);
 591                bch_uuid_write(d->c);
 592        }
 593
 594        if (attr == &sysfs_unregister) {
 595                set_bit(BCACHE_DEV_DETACHING, &d->flags);
 596                bcache_device_stop(d);
 597        }
 598
 599        return size;
 600}
 601STORE_LOCKED(bch_flash_dev)
 602
 603static struct attribute *bch_flash_dev_files[] = {
 604        &sysfs_unregister,
 605#if 0
 606        &sysfs_data_csum,
 607#endif
 608        &sysfs_label,
 609        &sysfs_size,
 610        NULL
 611};
 612KTYPE(bch_flash_dev);
 613
 614struct bset_stats_op {
 615        struct btree_op op;
 616        size_t nodes;
 617        struct bset_stats stats;
 618};
 619
 620static int bch_btree_bset_stats(struct btree_op *b_op, struct btree *b)
 621{
 622        struct bset_stats_op *op = container_of(b_op, struct bset_stats_op, op);
 623
 624        op->nodes++;
 625        bch_btree_keys_stats(&b->keys, &op->stats);
 626
 627        return MAP_CONTINUE;
 628}
 629
 630static int bch_bset_print_stats(struct cache_set *c, char *buf)
 631{
 632        struct bset_stats_op op;
 633        int ret;
 634
 635        memset(&op, 0, sizeof(op));
 636        bch_btree_op_init(&op.op, -1);
 637
 638        ret = bch_btree_map_nodes(&op.op, c, &ZERO_KEY, bch_btree_bset_stats);
 639        if (ret < 0)
 640                return ret;
 641
 642        return snprintf(buf, PAGE_SIZE,
 643                        "btree nodes:           %zu\n"
 644                        "written sets:          %zu\n"
 645                        "unwritten sets:                %zu\n"
 646                        "written key bytes:     %zu\n"
 647                        "unwritten key bytes:   %zu\n"
 648                        "floats:                        %zu\n"
 649                        "failed:                        %zu\n",
 650                        op.nodes,
 651                        op.stats.sets_written, op.stats.sets_unwritten,
 652                        op.stats.bytes_written, op.stats.bytes_unwritten,
 653                        op.stats.floats, op.stats.failed);
 654}
 655
 656static unsigned int bch_root_usage(struct cache_set *c)
 657{
 658        unsigned int bytes = 0;
 659        struct bkey *k;
 660        struct btree *b;
 661        struct btree_iter iter;
 662
 663        goto lock_root;
 664
 665        do {
 666                rw_unlock(false, b);
 667lock_root:
 668                b = c->root;
 669                rw_lock(false, b, b->level);
 670        } while (b != c->root);
 671
 672        for_each_key_filter(&b->keys, k, &iter, bch_ptr_bad)
 673                bytes += bkey_bytes(k);
 674
 675        rw_unlock(false, b);
 676
 677        return (bytes * 100) / btree_bytes(c);
 678}
 679
 680static size_t bch_cache_size(struct cache_set *c)
 681{
 682        size_t ret = 0;
 683        struct btree *b;
 684
 685        mutex_lock(&c->bucket_lock);
 686        list_for_each_entry(b, &c->btree_cache, list)
 687                ret += 1 << (b->keys.page_order + PAGE_SHIFT);
 688
 689        mutex_unlock(&c->bucket_lock);
 690        return ret;
 691}
 692
 693static unsigned int bch_cache_max_chain(struct cache_set *c)
 694{
 695        unsigned int ret = 0;
 696        struct hlist_head *h;
 697
 698        mutex_lock(&c->bucket_lock);
 699
 700        for (h = c->bucket_hash;
 701             h < c->bucket_hash + (1 << BUCKET_HASH_BITS);
 702             h++) {
 703                unsigned int i = 0;
 704                struct hlist_node *p;
 705
 706                hlist_for_each(p, h)
 707                        i++;
 708
 709                ret = max(ret, i);
 710        }
 711
 712        mutex_unlock(&c->bucket_lock);
 713        return ret;
 714}
 715
 716static unsigned int bch_btree_used(struct cache_set *c)
 717{
 718        return div64_u64(c->gc_stats.key_bytes * 100,
 719                         (c->gc_stats.nodes ?: 1) * btree_bytes(c));
 720}
 721
 722static unsigned int bch_average_key_size(struct cache_set *c)
 723{
 724        return c->gc_stats.nkeys
 725                ? div64_u64(c->gc_stats.data, c->gc_stats.nkeys)
 726                : 0;
 727}
 728
 729SHOW(__bch_cache_set)
 730{
 731        struct cache_set *c = container_of(kobj, struct cache_set, kobj);
 732
 733        sysfs_print(synchronous,                CACHE_SYNC(&c->cache->sb));
 734        sysfs_print(journal_delay_ms,           c->journal_delay_ms);
 735        sysfs_hprint(bucket_size,               bucket_bytes(c->cache));
 736        sysfs_hprint(block_size,                block_bytes(c->cache));
 737        sysfs_print(tree_depth,                 c->root->level);
 738        sysfs_print(root_usage_percent,         bch_root_usage(c));
 739
 740        sysfs_hprint(btree_cache_size,          bch_cache_size(c));
 741        sysfs_print(btree_cache_max_chain,      bch_cache_max_chain(c));
 742        sysfs_print(cache_available_percent,    100 - c->gc_stats.in_use);
 743
 744        sysfs_print_time_stats(&c->btree_gc_time,       btree_gc, sec, ms);
 745        sysfs_print_time_stats(&c->btree_split_time,    btree_split, sec, us);
 746        sysfs_print_time_stats(&c->sort.time,           btree_sort, ms, us);
 747        sysfs_print_time_stats(&c->btree_read_time,     btree_read, ms, us);
 748
 749        sysfs_print(btree_used_percent, bch_btree_used(c));
 750        sysfs_print(btree_nodes,        c->gc_stats.nodes);
 751        sysfs_hprint(average_key_size,  bch_average_key_size(c));
 752
 753        sysfs_print(cache_read_races,
 754                    atomic_long_read(&c->cache_read_races));
 755
 756        sysfs_print(reclaim,
 757                    atomic_long_read(&c->reclaim));
 758
 759        sysfs_print(reclaimed_journal_buckets,
 760                    atomic_long_read(&c->reclaimed_journal_buckets));
 761
 762        sysfs_print(flush_write,
 763                    atomic_long_read(&c->flush_write));
 764
 765        sysfs_print(writeback_keys_done,
 766                    atomic_long_read(&c->writeback_keys_done));
 767        sysfs_print(writeback_keys_failed,
 768                    atomic_long_read(&c->writeback_keys_failed));
 769
 770        if (attr == &sysfs_errors)
 771                return bch_snprint_string_list(buf, PAGE_SIZE, error_actions,
 772                                               c->on_error);
 773
 774        /* See count_io_errors for why 88 */
 775        sysfs_print(io_error_halflife,  c->error_decay * 88);
 776        sysfs_print(io_error_limit,     c->error_limit);
 777
 778        sysfs_hprint(congested,
 779                     ((uint64_t) bch_get_congested(c)) << 9);
 780        sysfs_print(congested_read_threshold_us,
 781                    c->congested_read_threshold_us);
 782        sysfs_print(congested_write_threshold_us,
 783                    c->congested_write_threshold_us);
 784
 785        sysfs_print(cutoff_writeback, bch_cutoff_writeback);
 786        sysfs_print(cutoff_writeback_sync, bch_cutoff_writeback_sync);
 787
 788        sysfs_print(active_journal_entries,     fifo_used(&c->journal.pin));
 789        sysfs_printf(verify,                    "%i", c->verify);
 790        sysfs_printf(key_merging_disabled,      "%i", c->key_merging_disabled);
 791        sysfs_printf(expensive_debug_checks,
 792                     "%i", c->expensive_debug_checks);
 793        sysfs_printf(gc_always_rewrite,         "%i", c->gc_always_rewrite);
 794        sysfs_printf(btree_shrinker_disabled,   "%i", c->shrinker_disabled);
 795        sysfs_printf(copy_gc_enabled,           "%i", c->copy_gc_enabled);
 796        sysfs_printf(idle_max_writeback_rate,   "%i",
 797                     c->idle_max_writeback_rate_enabled);
 798        sysfs_printf(gc_after_writeback,        "%i", c->gc_after_writeback);
 799        sysfs_printf(io_disable,                "%i",
 800                     test_bit(CACHE_SET_IO_DISABLE, &c->flags));
 801
 802        if (attr == &sysfs_bset_tree_stats)
 803                return bch_bset_print_stats(c, buf);
 804
 805        if (attr == &sysfs_feature_compat)
 806                return bch_print_cache_set_feature_compat(c, buf, PAGE_SIZE);
 807        if (attr == &sysfs_feature_ro_compat)
 808                return bch_print_cache_set_feature_ro_compat(c, buf, PAGE_SIZE);
 809        if (attr == &sysfs_feature_incompat)
 810                return bch_print_cache_set_feature_incompat(c, buf, PAGE_SIZE);
 811
 812        return 0;
 813}
 814SHOW_LOCKED(bch_cache_set)
 815
 816STORE(__bch_cache_set)
 817{
 818        struct cache_set *c = container_of(kobj, struct cache_set, kobj);
 819        ssize_t v;
 820
 821        /* no user space access if system is rebooting */
 822        if (bcache_is_reboot)
 823                return -EBUSY;
 824
 825        if (attr == &sysfs_unregister)
 826                bch_cache_set_unregister(c);
 827
 828        if (attr == &sysfs_stop)
 829                bch_cache_set_stop(c);
 830
 831        if (attr == &sysfs_synchronous) {
 832                bool sync = strtoul_or_return(buf);
 833
 834                if (sync != CACHE_SYNC(&c->cache->sb)) {
 835                        SET_CACHE_SYNC(&c->cache->sb, sync);
 836                        bcache_write_super(c);
 837                }
 838        }
 839
 840        if (attr == &sysfs_flash_vol_create) {
 841                int r;
 842                uint64_t v;
 843
 844                strtoi_h_or_return(buf, v);
 845
 846                r = bch_flash_dev_create(c, v);
 847                if (r)
 848                        return r;
 849        }
 850
 851        if (attr == &sysfs_clear_stats) {
 852                atomic_long_set(&c->writeback_keys_done,        0);
 853                atomic_long_set(&c->writeback_keys_failed,      0);
 854
 855                memset(&c->gc_stats, 0, sizeof(struct gc_stat));
 856                bch_cache_accounting_clear(&c->accounting);
 857        }
 858
 859        if (attr == &sysfs_trigger_gc)
 860                force_wake_up_gc(c);
 861
 862        if (attr == &sysfs_prune_cache) {
 863                struct shrink_control sc;
 864
 865                sc.gfp_mask = GFP_KERNEL;
 866                sc.nr_to_scan = strtoul_or_return(buf);
 867                c->shrink.scan_objects(&c->shrink, &sc);
 868        }
 869
 870        sysfs_strtoul_clamp(congested_read_threshold_us,
 871                            c->congested_read_threshold_us,
 872                            0, UINT_MAX);
 873        sysfs_strtoul_clamp(congested_write_threshold_us,
 874                            c->congested_write_threshold_us,
 875                            0, UINT_MAX);
 876
 877        if (attr == &sysfs_errors) {
 878                v = __sysfs_match_string(error_actions, -1, buf);
 879                if (v < 0)
 880                        return v;
 881
 882                c->on_error = v;
 883        }
 884
 885        sysfs_strtoul_clamp(io_error_limit, c->error_limit, 0, UINT_MAX);
 886
 887        /* See count_io_errors() for why 88 */
 888        if (attr == &sysfs_io_error_halflife) {
 889                unsigned long v = 0;
 890                ssize_t ret;
 891
 892                ret = strtoul_safe_clamp(buf, v, 0, UINT_MAX);
 893                if (!ret) {
 894                        c->error_decay = v / 88;
 895                        return size;
 896                }
 897                return ret;
 898        }
 899
 900        if (attr == &sysfs_io_disable) {
 901                v = strtoul_or_return(buf);
 902                if (v) {
 903                        if (test_and_set_bit(CACHE_SET_IO_DISABLE,
 904                                             &c->flags))
 905                                pr_warn("CACHE_SET_IO_DISABLE already set\n");
 906                } else {
 907                        if (!test_and_clear_bit(CACHE_SET_IO_DISABLE,
 908                                                &c->flags))
 909                                pr_warn("CACHE_SET_IO_DISABLE already cleared\n");
 910                }
 911        }
 912
 913        sysfs_strtoul_clamp(journal_delay_ms,
 914                            c->journal_delay_ms,
 915                            0, USHRT_MAX);
 916        sysfs_strtoul_bool(verify,              c->verify);
 917        sysfs_strtoul_bool(key_merging_disabled, c->key_merging_disabled);
 918        sysfs_strtoul(expensive_debug_checks,   c->expensive_debug_checks);
 919        sysfs_strtoul_bool(gc_always_rewrite,   c->gc_always_rewrite);
 920        sysfs_strtoul_bool(btree_shrinker_disabled, c->shrinker_disabled);
 921        sysfs_strtoul_bool(copy_gc_enabled,     c->copy_gc_enabled);
 922        sysfs_strtoul_bool(idle_max_writeback_rate,
 923                           c->idle_max_writeback_rate_enabled);
 924
 925        /*
 926         * write gc_after_writeback here may overwrite an already set
 927         * BCH_DO_AUTO_GC, it doesn't matter because this flag will be
 928         * set in next chance.
 929         */
 930        sysfs_strtoul_clamp(gc_after_writeback, c->gc_after_writeback, 0, 1);
 931
 932        return size;
 933}
 934STORE_LOCKED(bch_cache_set)
 935
 936SHOW(bch_cache_set_internal)
 937{
 938        struct cache_set *c = container_of(kobj, struct cache_set, internal);
 939
 940        return bch_cache_set_show(&c->kobj, attr, buf);
 941}
 942
 943STORE(bch_cache_set_internal)
 944{
 945        struct cache_set *c = container_of(kobj, struct cache_set, internal);
 946
 947        /* no user space access if system is rebooting */
 948        if (bcache_is_reboot)
 949                return -EBUSY;
 950
 951        return bch_cache_set_store(&c->kobj, attr, buf, size);
 952}
 953
 954static void bch_cache_set_internal_release(struct kobject *k)
 955{
 956}
 957
 958static struct attribute *bch_cache_set_files[] = {
 959        &sysfs_unregister,
 960        &sysfs_stop,
 961        &sysfs_synchronous,
 962        &sysfs_journal_delay_ms,
 963        &sysfs_flash_vol_create,
 964
 965        &sysfs_bucket_size,
 966        &sysfs_block_size,
 967        &sysfs_tree_depth,
 968        &sysfs_root_usage_percent,
 969        &sysfs_btree_cache_size,
 970        &sysfs_cache_available_percent,
 971
 972        &sysfs_average_key_size,
 973
 974        &sysfs_errors,
 975        &sysfs_io_error_limit,
 976        &sysfs_io_error_halflife,
 977        &sysfs_congested,
 978        &sysfs_congested_read_threshold_us,
 979        &sysfs_congested_write_threshold_us,
 980        &sysfs_clear_stats,
 981        NULL
 982};
 983KTYPE(bch_cache_set);
 984
 985static struct attribute *bch_cache_set_internal_files[] = {
 986        &sysfs_active_journal_entries,
 987
 988        sysfs_time_stats_attribute_list(btree_gc, sec, ms)
 989        sysfs_time_stats_attribute_list(btree_split, sec, us)
 990        sysfs_time_stats_attribute_list(btree_sort, ms, us)
 991        sysfs_time_stats_attribute_list(btree_read, ms, us)
 992
 993        &sysfs_btree_nodes,
 994        &sysfs_btree_used_percent,
 995        &sysfs_btree_cache_max_chain,
 996
 997        &sysfs_bset_tree_stats,
 998        &sysfs_cache_read_races,
 999        &sysfs_reclaim,
1000        &sysfs_reclaimed_journal_buckets,
1001        &sysfs_flush_write,
1002        &sysfs_writeback_keys_done,
1003        &sysfs_writeback_keys_failed,
1004
1005        &sysfs_trigger_gc,
1006        &sysfs_prune_cache,
1007#ifdef CONFIG_BCACHE_DEBUG
1008        &sysfs_verify,
1009        &sysfs_key_merging_disabled,
1010        &sysfs_expensive_debug_checks,
1011#endif
1012        &sysfs_gc_always_rewrite,
1013        &sysfs_btree_shrinker_disabled,
1014        &sysfs_copy_gc_enabled,
1015        &sysfs_idle_max_writeback_rate,
1016        &sysfs_gc_after_writeback,
1017        &sysfs_io_disable,
1018        &sysfs_cutoff_writeback,
1019        &sysfs_cutoff_writeback_sync,
1020        &sysfs_feature_compat,
1021        &sysfs_feature_ro_compat,
1022        &sysfs_feature_incompat,
1023        NULL
1024};
1025KTYPE(bch_cache_set_internal);
1026
1027static int __bch_cache_cmp(const void *l, const void *r)
1028{
1029        cond_resched();
1030        return *((uint16_t *)r) - *((uint16_t *)l);
1031}
1032
1033SHOW(__bch_cache)
1034{
1035        struct cache *ca = container_of(kobj, struct cache, kobj);
1036
1037        sysfs_hprint(bucket_size,       bucket_bytes(ca));
1038        sysfs_hprint(block_size,        block_bytes(ca));
1039        sysfs_print(nbuckets,           ca->sb.nbuckets);
1040        sysfs_print(discard,            ca->discard);
1041        sysfs_hprint(written, atomic_long_read(&ca->sectors_written) << 9);
1042        sysfs_hprint(btree_written,
1043                     atomic_long_read(&ca->btree_sectors_written) << 9);
1044        sysfs_hprint(metadata_written,
1045                     (atomic_long_read(&ca->meta_sectors_written) +
1046                      atomic_long_read(&ca->btree_sectors_written)) << 9);
1047
1048        sysfs_print(io_errors,
1049                    atomic_read(&ca->io_errors) >> IO_ERROR_SHIFT);
1050
1051        if (attr == &sysfs_cache_replacement_policy)
1052                return bch_snprint_string_list(buf, PAGE_SIZE,
1053                                               cache_replacement_policies,
1054                                               CACHE_REPLACEMENT(&ca->sb));
1055
1056        if (attr == &sysfs_priority_stats) {
1057                struct bucket *b;
1058                size_t n = ca->sb.nbuckets, i;
1059                size_t unused = 0, available = 0, dirty = 0, meta = 0;
1060                uint64_t sum = 0;
1061                /* Compute 31 quantiles */
1062                uint16_t q[31], *p, *cached;
1063                ssize_t ret;
1064
1065                cached = p = vmalloc(array_size(sizeof(uint16_t),
1066                                                ca->sb.nbuckets));
1067                if (!p)
1068                        return -ENOMEM;
1069
1070                mutex_lock(&ca->set->bucket_lock);
1071                for_each_bucket(b, ca) {
1072                        if (!GC_SECTORS_USED(b))
1073                                unused++;
1074                        if (GC_MARK(b) == GC_MARK_RECLAIMABLE)
1075                                available++;
1076                        if (GC_MARK(b) == GC_MARK_DIRTY)
1077                                dirty++;
1078                        if (GC_MARK(b) == GC_MARK_METADATA)
1079                                meta++;
1080                }
1081
1082                for (i = ca->sb.first_bucket; i < n; i++)
1083                        p[i] = ca->buckets[i].prio;
1084                mutex_unlock(&ca->set->bucket_lock);
1085
1086                sort(p, n, sizeof(uint16_t), __bch_cache_cmp, NULL);
1087
1088                while (n &&
1089                       !cached[n - 1])
1090                        --n;
1091
1092                while (cached < p + n &&
1093                       *cached == BTREE_PRIO) {
1094                        cached++;
1095                        n--;
1096                }
1097
1098                for (i = 0; i < n; i++)
1099                        sum += INITIAL_PRIO - cached[i];
1100
1101                if (n)
1102                        do_div(sum, n);
1103
1104                for (i = 0; i < ARRAY_SIZE(q); i++)
1105                        q[i] = INITIAL_PRIO - cached[n * (i + 1) /
1106                                (ARRAY_SIZE(q) + 1)];
1107
1108                vfree(p);
1109
1110                ret = scnprintf(buf, PAGE_SIZE,
1111                                "Unused:                %zu%%\n"
1112                                "Clean:         %zu%%\n"
1113                                "Dirty:         %zu%%\n"
1114                                "Metadata:      %zu%%\n"
1115                                "Average:       %llu\n"
1116                                "Sectors per Q: %zu\n"
1117                                "Quantiles:     [",
1118                                unused * 100 / (size_t) ca->sb.nbuckets,
1119                                available * 100 / (size_t) ca->sb.nbuckets,
1120                                dirty * 100 / (size_t) ca->sb.nbuckets,
1121                                meta * 100 / (size_t) ca->sb.nbuckets, sum,
1122                                n * ca->sb.bucket_size / (ARRAY_SIZE(q) + 1));
1123
1124                for (i = 0; i < ARRAY_SIZE(q); i++)
1125                        ret += scnprintf(buf + ret, PAGE_SIZE - ret,
1126                                         "%u ", q[i]);
1127                ret--;
1128
1129                ret += scnprintf(buf + ret, PAGE_SIZE - ret, "]\n");
1130
1131                return ret;
1132        }
1133
1134        return 0;
1135}
1136SHOW_LOCKED(bch_cache)
1137
1138STORE(__bch_cache)
1139{
1140        struct cache *ca = container_of(kobj, struct cache, kobj);
1141        ssize_t v;
1142
1143        /* no user space access if system is rebooting */
1144        if (bcache_is_reboot)
1145                return -EBUSY;
1146
1147        if (attr == &sysfs_discard) {
1148                bool v = strtoul_or_return(buf);
1149
1150                if (blk_queue_discard(bdev_get_queue(ca->bdev)))
1151                        ca->discard = v;
1152
1153                if (v != CACHE_DISCARD(&ca->sb)) {
1154                        SET_CACHE_DISCARD(&ca->sb, v);
1155                        bcache_write_super(ca->set);
1156                }
1157        }
1158
1159        if (attr == &sysfs_cache_replacement_policy) {
1160                v = __sysfs_match_string(cache_replacement_policies, -1, buf);
1161                if (v < 0)
1162                        return v;
1163
1164                if ((unsigned int) v != CACHE_REPLACEMENT(&ca->sb)) {
1165                        mutex_lock(&ca->set->bucket_lock);
1166                        SET_CACHE_REPLACEMENT(&ca->sb, v);
1167                        mutex_unlock(&ca->set->bucket_lock);
1168
1169                        bcache_write_super(ca->set);
1170                }
1171        }
1172
1173        if (attr == &sysfs_clear_stats) {
1174                atomic_long_set(&ca->sectors_written, 0);
1175                atomic_long_set(&ca->btree_sectors_written, 0);
1176                atomic_long_set(&ca->meta_sectors_written, 0);
1177                atomic_set(&ca->io_count, 0);
1178                atomic_set(&ca->io_errors, 0);
1179        }
1180
1181        return size;
1182}
1183STORE_LOCKED(bch_cache)
1184
1185static struct attribute *bch_cache_files[] = {
1186        &sysfs_bucket_size,
1187        &sysfs_block_size,
1188        &sysfs_nbuckets,
1189        &sysfs_priority_stats,
1190        &sysfs_discard,
1191        &sysfs_written,
1192        &sysfs_btree_written,
1193        &sysfs_metadata_written,
1194        &sysfs_io_errors,
1195        &sysfs_clear_stats,
1196        &sysfs_cache_replacement_policy,
1197        NULL
1198};
1199KTYPE(bch_cache);
1200