Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / md / bcache / sysfs.c
diff --git a/kernel/drivers/md/bcache/sysfs.c b/kernel/drivers/md/bcache/sysfs.c
new file mode 100644 (file)
index 0000000..b3ff57d
--- /dev/null
@@ -0,0 +1,898 @@
+/*
+ * bcache sysfs interfaces
+ *
+ * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
+ * Copyright 2012 Google, Inc.
+ */
+
+#include "bcache.h"
+#include "sysfs.h"
+#include "btree.h"
+#include "request.h"
+#include "writeback.h"
+
+#include <linux/blkdev.h>
+#include <linux/sort.h>
+
+static const char * const cache_replacement_policies[] = {
+       "lru",
+       "fifo",
+       "random",
+       NULL
+};
+
+static const char * const error_actions[] = {
+       "unregister",
+       "panic",
+       NULL
+};
+
+write_attribute(attach);
+write_attribute(detach);
+write_attribute(unregister);
+write_attribute(stop);
+write_attribute(clear_stats);
+write_attribute(trigger_gc);
+write_attribute(prune_cache);
+write_attribute(flash_vol_create);
+
+read_attribute(bucket_size);
+read_attribute(block_size);
+read_attribute(nbuckets);
+read_attribute(tree_depth);
+read_attribute(root_usage_percent);
+read_attribute(priority_stats);
+read_attribute(btree_cache_size);
+read_attribute(btree_cache_max_chain);
+read_attribute(cache_available_percent);
+read_attribute(written);
+read_attribute(btree_written);
+read_attribute(metadata_written);
+read_attribute(active_journal_entries);
+
+sysfs_time_stats_attribute(btree_gc,   sec, ms);
+sysfs_time_stats_attribute(btree_split, sec, us);
+sysfs_time_stats_attribute(btree_sort, ms,  us);
+sysfs_time_stats_attribute(btree_read, ms,  us);
+
+read_attribute(btree_nodes);
+read_attribute(btree_used_percent);
+read_attribute(average_key_size);
+read_attribute(dirty_data);
+read_attribute(bset_tree_stats);
+
+read_attribute(state);
+read_attribute(cache_read_races);
+read_attribute(writeback_keys_done);
+read_attribute(writeback_keys_failed);
+read_attribute(io_errors);
+read_attribute(congested);
+rw_attribute(congested_read_threshold_us);
+rw_attribute(congested_write_threshold_us);
+
+rw_attribute(sequential_cutoff);
+rw_attribute(data_csum);
+rw_attribute(cache_mode);
+rw_attribute(writeback_metadata);
+rw_attribute(writeback_running);
+rw_attribute(writeback_percent);
+rw_attribute(writeback_delay);
+rw_attribute(writeback_rate);
+
+rw_attribute(writeback_rate_update_seconds);
+rw_attribute(writeback_rate_d_term);
+rw_attribute(writeback_rate_p_term_inverse);
+read_attribute(writeback_rate_debug);
+
+read_attribute(stripe_size);
+read_attribute(partial_stripes_expensive);
+
+rw_attribute(synchronous);
+rw_attribute(journal_delay_ms);
+rw_attribute(discard);
+rw_attribute(running);
+rw_attribute(label);
+rw_attribute(readahead);
+rw_attribute(errors);
+rw_attribute(io_error_limit);
+rw_attribute(io_error_halflife);
+rw_attribute(verify);
+rw_attribute(bypass_torture_test);
+rw_attribute(key_merging_disabled);
+rw_attribute(gc_always_rewrite);
+rw_attribute(expensive_debug_checks);
+rw_attribute(cache_replacement_policy);
+rw_attribute(btree_shrinker_disabled);
+rw_attribute(copy_gc_enabled);
+rw_attribute(size);
+
+SHOW(__bch_cached_dev)
+{
+       struct cached_dev *dc = container_of(kobj, struct cached_dev,
+                                            disk.kobj);
+       const char *states[] = { "no cache", "clean", "dirty", "inconsistent" };
+
+#define var(stat)              (dc->stat)
+
+       if (attr == &sysfs_cache_mode)
+               return bch_snprint_string_list(buf, PAGE_SIZE,
+                                              bch_cache_modes + 1,
+                                              BDEV_CACHE_MODE(&dc->sb));
+
+       sysfs_printf(data_csum,         "%i", dc->disk.data_csum);
+       var_printf(verify,              "%i");
+       var_printf(bypass_torture_test, "%i");
+       var_printf(writeback_metadata,  "%i");
+       var_printf(writeback_running,   "%i");
+       var_print(writeback_delay);
+       var_print(writeback_percent);
+       sysfs_hprint(writeback_rate,    dc->writeback_rate.rate << 9);
+
+       var_print(writeback_rate_update_seconds);
+       var_print(writeback_rate_d_term);
+       var_print(writeback_rate_p_term_inverse);
+
+       if (attr == &sysfs_writeback_rate_debug) {
+               char rate[20];
+               char dirty[20];
+               char target[20];
+               char proportional[20];
+               char derivative[20];
+               char change[20];
+               s64 next_io;
+
+               bch_hprint(rate,        dc->writeback_rate.rate << 9);
+               bch_hprint(dirty,       bcache_dev_sectors_dirty(&dc->disk) << 9);
+               bch_hprint(target,      dc->writeback_rate_target << 9);
+               bch_hprint(proportional,dc->writeback_rate_proportional << 9);
+               bch_hprint(derivative,  dc->writeback_rate_derivative << 9);
+               bch_hprint(change,      dc->writeback_rate_change << 9);
+
+               next_io = div64_s64(dc->writeback_rate.next - local_clock(),
+                                   NSEC_PER_MSEC);
+
+               return sprintf(buf,
+                              "rate:\t\t%s/sec\n"
+                              "dirty:\t\t%s\n"
+                              "target:\t\t%s\n"
+                              "proportional:\t%s\n"
+                              "derivative:\t%s\n"
+                              "change:\t\t%s/sec\n"
+                              "next io:\t%llims\n",
+                              rate, dirty, target, proportional,
+                              derivative, change, next_io);
+       }
+
+       sysfs_hprint(dirty_data,
+                    bcache_dev_sectors_dirty(&dc->disk) << 9);
+
+       sysfs_hprint(stripe_size,       dc->disk.stripe_size << 9);
+       var_printf(partial_stripes_expensive,   "%u");
+
+       var_hprint(sequential_cutoff);
+       var_hprint(readahead);
+
+       sysfs_print(running,            atomic_read(&dc->running));
+       sysfs_print(state,              states[BDEV_STATE(&dc->sb)]);
+
+       if (attr == &sysfs_label) {
+               memcpy(buf, dc->sb.label, SB_LABEL_SIZE);
+               buf[SB_LABEL_SIZE + 1] = '\0';
+               strcat(buf, "\n");
+               return strlen(buf);
+       }
+
+#undef var
+       return 0;
+}
+SHOW_LOCKED(bch_cached_dev)
+
+STORE(__cached_dev)
+{
+       struct cached_dev *dc = container_of(kobj, struct cached_dev,
+                                            disk.kobj);
+       unsigned v = size;
+       struct cache_set *c;
+       struct kobj_uevent_env *env;
+
+#define d_strtoul(var)         sysfs_strtoul(var, dc->var)
+#define d_strtoul_nonzero(var) sysfs_strtoul_clamp(var, dc->var, 1, INT_MAX)
+#define d_strtoi_h(var)                sysfs_hatoi(var, dc->var)
+
+       sysfs_strtoul(data_csum,        dc->disk.data_csum);
+       d_strtoul(verify);
+       d_strtoul(bypass_torture_test);
+       d_strtoul(writeback_metadata);
+       d_strtoul(writeback_running);
+       d_strtoul(writeback_delay);
+
+       sysfs_strtoul_clamp(writeback_percent, dc->writeback_percent, 0, 40);
+
+       sysfs_strtoul_clamp(writeback_rate,
+                           dc->writeback_rate.rate, 1, INT_MAX);
+
+       d_strtoul_nonzero(writeback_rate_update_seconds);
+       d_strtoul(writeback_rate_d_term);
+       d_strtoul_nonzero(writeback_rate_p_term_inverse);
+
+       d_strtoi_h(sequential_cutoff);
+       d_strtoi_h(readahead);
+
+       if (attr == &sysfs_clear_stats)
+               bch_cache_accounting_clear(&dc->accounting);
+
+       if (attr == &sysfs_running &&
+           strtoul_or_return(buf))
+               bch_cached_dev_run(dc);
+
+       if (attr == &sysfs_cache_mode) {
+               ssize_t v = bch_read_string_list(buf, bch_cache_modes + 1);
+
+               if (v < 0)
+                       return v;
+
+               if ((unsigned) v != BDEV_CACHE_MODE(&dc->sb)) {
+                       SET_BDEV_CACHE_MODE(&dc->sb, v);
+                       bch_write_bdev_super(dc, NULL);
+               }
+       }
+
+       if (attr == &sysfs_label) {
+               if (size > SB_LABEL_SIZE)
+                       return -EINVAL;
+               memcpy(dc->sb.label, buf, size);
+               if (size < SB_LABEL_SIZE)
+                       dc->sb.label[size] = '\0';
+               if (size && dc->sb.label[size - 1] == '\n')
+                       dc->sb.label[size - 1] = '\0';
+               bch_write_bdev_super(dc, NULL);
+               if (dc->disk.c) {
+                       memcpy(dc->disk.c->uuids[dc->disk.id].label,
+                              buf, SB_LABEL_SIZE);
+                       bch_uuid_write(dc->disk.c);
+               }
+               env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL);
+               if (!env)
+                       return -ENOMEM;
+               add_uevent_var(env, "DRIVER=bcache");
+               add_uevent_var(env, "CACHED_UUID=%pU", dc->sb.uuid),
+               add_uevent_var(env, "CACHED_LABEL=%s", buf);
+               kobject_uevent_env(
+                       &disk_to_dev(dc->disk.disk)->kobj, KOBJ_CHANGE, env->envp);
+               kfree(env);
+       }
+
+       if (attr == &sysfs_attach) {
+               if (bch_parse_uuid(buf, dc->sb.set_uuid) < 16)
+                       return -EINVAL;
+
+               list_for_each_entry(c, &bch_cache_sets, list) {
+                       v = bch_cached_dev_attach(dc, c);
+                       if (!v)
+                               return size;
+               }
+
+               pr_err("Can't attach %s: cache set not found", buf);
+               size = v;
+       }
+
+       if (attr == &sysfs_detach && dc->disk.c)
+               bch_cached_dev_detach(dc);
+
+       if (attr == &sysfs_stop)
+               bcache_device_stop(&dc->disk);
+
+       return size;
+}
+
+STORE(bch_cached_dev)
+{
+       struct cached_dev *dc = container_of(kobj, struct cached_dev,
+                                            disk.kobj);
+
+       mutex_lock(&bch_register_lock);
+       size = __cached_dev_store(kobj, attr, buf, size);
+
+       if (attr == &sysfs_writeback_running)
+               bch_writeback_queue(dc);
+
+       if (attr == &sysfs_writeback_percent)
+               schedule_delayed_work(&dc->writeback_rate_update,
+                                     dc->writeback_rate_update_seconds * HZ);
+
+       mutex_unlock(&bch_register_lock);
+       return size;
+}
+
+static struct attribute *bch_cached_dev_files[] = {
+       &sysfs_attach,
+       &sysfs_detach,
+       &sysfs_stop,
+#if 0
+       &sysfs_data_csum,
+#endif
+       &sysfs_cache_mode,
+       &sysfs_writeback_metadata,
+       &sysfs_writeback_running,
+       &sysfs_writeback_delay,
+       &sysfs_writeback_percent,
+       &sysfs_writeback_rate,
+       &sysfs_writeback_rate_update_seconds,
+       &sysfs_writeback_rate_d_term,
+       &sysfs_writeback_rate_p_term_inverse,
+       &sysfs_writeback_rate_debug,
+       &sysfs_dirty_data,
+       &sysfs_stripe_size,
+       &sysfs_partial_stripes_expensive,
+       &sysfs_sequential_cutoff,
+       &sysfs_clear_stats,
+       &sysfs_running,
+       &sysfs_state,
+       &sysfs_label,
+       &sysfs_readahead,
+#ifdef CONFIG_BCACHE_DEBUG
+       &sysfs_verify,
+       &sysfs_bypass_torture_test,
+#endif
+       NULL
+};
+KTYPE(bch_cached_dev);
+
+SHOW(bch_flash_dev)
+{
+       struct bcache_device *d = container_of(kobj, struct bcache_device,
+                                              kobj);
+       struct uuid_entry *u = &d->c->uuids[d->id];
+
+       sysfs_printf(data_csum, "%i", d->data_csum);
+       sysfs_hprint(size,      u->sectors << 9);
+
+       if (attr == &sysfs_label) {
+               memcpy(buf, u->label, SB_LABEL_SIZE);
+               buf[SB_LABEL_SIZE + 1] = '\0';
+               strcat(buf, "\n");
+               return strlen(buf);
+       }
+
+       return 0;
+}
+
+STORE(__bch_flash_dev)
+{
+       struct bcache_device *d = container_of(kobj, struct bcache_device,
+                                              kobj);
+       struct uuid_entry *u = &d->c->uuids[d->id];
+
+       sysfs_strtoul(data_csum,        d->data_csum);
+
+       if (attr == &sysfs_size) {
+               uint64_t v;
+               strtoi_h_or_return(buf, v);
+
+               u->sectors = v >> 9;
+               bch_uuid_write(d->c);
+               set_capacity(d->disk, u->sectors);
+       }
+
+       if (attr == &sysfs_label) {
+               memcpy(u->label, buf, SB_LABEL_SIZE);
+               bch_uuid_write(d->c);
+       }
+
+       if (attr == &sysfs_unregister) {
+               set_bit(BCACHE_DEV_DETACHING, &d->flags);
+               bcache_device_stop(d);
+       }
+
+       return size;
+}
+STORE_LOCKED(bch_flash_dev)
+
+static struct attribute *bch_flash_dev_files[] = {
+       &sysfs_unregister,
+#if 0
+       &sysfs_data_csum,
+#endif
+       &sysfs_label,
+       &sysfs_size,
+       NULL
+};
+KTYPE(bch_flash_dev);
+
+struct bset_stats_op {
+       struct btree_op op;
+       size_t nodes;
+       struct bset_stats stats;
+};
+
+static int bch_btree_bset_stats(struct btree_op *b_op, struct btree *b)
+{
+       struct bset_stats_op *op = container_of(b_op, struct bset_stats_op, op);
+
+       op->nodes++;
+       bch_btree_keys_stats(&b->keys, &op->stats);
+
+       return MAP_CONTINUE;
+}
+
+static int bch_bset_print_stats(struct cache_set *c, char *buf)
+{
+       struct bset_stats_op op;
+       int ret;
+
+       memset(&op, 0, sizeof(op));
+       bch_btree_op_init(&op.op, -1);
+
+       ret = bch_btree_map_nodes(&op.op, c, &ZERO_KEY, bch_btree_bset_stats);
+       if (ret < 0)
+               return ret;
+
+       return snprintf(buf, PAGE_SIZE,
+                       "btree nodes:           %zu\n"
+                       "written sets:          %zu\n"
+                       "unwritten sets:                %zu\n"
+                       "written key bytes:     %zu\n"
+                       "unwritten key bytes:   %zu\n"
+                       "floats:                        %zu\n"
+                       "failed:                        %zu\n",
+                       op.nodes,
+                       op.stats.sets_written, op.stats.sets_unwritten,
+                       op.stats.bytes_written, op.stats.bytes_unwritten,
+                       op.stats.floats, op.stats.failed);
+}
+
+static unsigned bch_root_usage(struct cache_set *c)
+{
+       unsigned bytes = 0;
+       struct bkey *k;
+       struct btree *b;
+       struct btree_iter iter;
+
+       goto lock_root;
+
+       do {
+               rw_unlock(false, b);
+lock_root:
+               b = c->root;
+               rw_lock(false, b, b->level);
+       } while (b != c->root);
+
+       for_each_key_filter(&b->keys, k, &iter, bch_ptr_bad)
+               bytes += bkey_bytes(k);
+
+       rw_unlock(false, b);
+
+       return (bytes * 100) / btree_bytes(c);
+}
+
+static size_t bch_cache_size(struct cache_set *c)
+{
+       size_t ret = 0;
+       struct btree *b;
+
+       mutex_lock(&c->bucket_lock);
+       list_for_each_entry(b, &c->btree_cache, list)
+               ret += 1 << (b->keys.page_order + PAGE_SHIFT);
+
+       mutex_unlock(&c->bucket_lock);
+       return ret;
+}
+
+static unsigned bch_cache_max_chain(struct cache_set *c)
+{
+       unsigned ret = 0;
+       struct hlist_head *h;
+
+       mutex_lock(&c->bucket_lock);
+
+       for (h = c->bucket_hash;
+            h < c->bucket_hash + (1 << BUCKET_HASH_BITS);
+            h++) {
+               unsigned i = 0;
+               struct hlist_node *p;
+
+               hlist_for_each(p, h)
+                       i++;
+
+               ret = max(ret, i);
+       }
+
+       mutex_unlock(&c->bucket_lock);
+       return ret;
+}
+
+static unsigned bch_btree_used(struct cache_set *c)
+{
+       return div64_u64(c->gc_stats.key_bytes * 100,
+                        (c->gc_stats.nodes ?: 1) * btree_bytes(c));
+}
+
+static unsigned bch_average_key_size(struct cache_set *c)
+{
+       return c->gc_stats.nkeys
+               ? div64_u64(c->gc_stats.data, c->gc_stats.nkeys)
+               : 0;
+}
+
+SHOW(__bch_cache_set)
+{
+       struct cache_set *c = container_of(kobj, struct cache_set, kobj);
+
+       sysfs_print(synchronous,                CACHE_SYNC(&c->sb));
+       sysfs_print(journal_delay_ms,           c->journal_delay_ms);
+       sysfs_hprint(bucket_size,               bucket_bytes(c));
+       sysfs_hprint(block_size,                block_bytes(c));
+       sysfs_print(tree_depth,                 c->root->level);
+       sysfs_print(root_usage_percent,         bch_root_usage(c));
+
+       sysfs_hprint(btree_cache_size,          bch_cache_size(c));
+       sysfs_print(btree_cache_max_chain,      bch_cache_max_chain(c));
+       sysfs_print(cache_available_percent,    100 - c->gc_stats.in_use);
+
+       sysfs_print_time_stats(&c->btree_gc_time,       btree_gc, sec, ms);
+       sysfs_print_time_stats(&c->btree_split_time,    btree_split, sec, us);
+       sysfs_print_time_stats(&c->sort.time,           btree_sort, ms, us);
+       sysfs_print_time_stats(&c->btree_read_time,     btree_read, ms, us);
+
+       sysfs_print(btree_used_percent, bch_btree_used(c));
+       sysfs_print(btree_nodes,        c->gc_stats.nodes);
+       sysfs_hprint(average_key_size,  bch_average_key_size(c));
+
+       sysfs_print(cache_read_races,
+                   atomic_long_read(&c->cache_read_races));
+
+       sysfs_print(writeback_keys_done,
+                   atomic_long_read(&c->writeback_keys_done));
+       sysfs_print(writeback_keys_failed,
+                   atomic_long_read(&c->writeback_keys_failed));
+
+       if (attr == &sysfs_errors)
+               return bch_snprint_string_list(buf, PAGE_SIZE, error_actions,
+                                              c->on_error);
+
+       /* See count_io_errors for why 88 */
+       sysfs_print(io_error_halflife,  c->error_decay * 88);
+       sysfs_print(io_error_limit,     c->error_limit >> IO_ERROR_SHIFT);
+
+       sysfs_hprint(congested,
+                    ((uint64_t) bch_get_congested(c)) << 9);
+       sysfs_print(congested_read_threshold_us,
+                   c->congested_read_threshold_us);
+       sysfs_print(congested_write_threshold_us,
+                   c->congested_write_threshold_us);
+
+       sysfs_print(active_journal_entries,     fifo_used(&c->journal.pin));
+       sysfs_printf(verify,                    "%i", c->verify);
+       sysfs_printf(key_merging_disabled,      "%i", c->key_merging_disabled);
+       sysfs_printf(expensive_debug_checks,
+                    "%i", c->expensive_debug_checks);
+       sysfs_printf(gc_always_rewrite,         "%i", c->gc_always_rewrite);
+       sysfs_printf(btree_shrinker_disabled,   "%i", c->shrinker_disabled);
+       sysfs_printf(copy_gc_enabled,           "%i", c->copy_gc_enabled);
+
+       if (attr == &sysfs_bset_tree_stats)
+               return bch_bset_print_stats(c, buf);
+
+       return 0;
+}
+SHOW_LOCKED(bch_cache_set)
+
+STORE(__bch_cache_set)
+{
+       struct cache_set *c = container_of(kobj, struct cache_set, kobj);
+
+       if (attr == &sysfs_unregister)
+               bch_cache_set_unregister(c);
+
+       if (attr == &sysfs_stop)
+               bch_cache_set_stop(c);
+
+       if (attr == &sysfs_synchronous) {
+               bool sync = strtoul_or_return(buf);
+
+               if (sync != CACHE_SYNC(&c->sb)) {
+                       SET_CACHE_SYNC(&c->sb, sync);
+                       bcache_write_super(c);
+               }
+       }
+
+       if (attr == &sysfs_flash_vol_create) {
+               int r;
+               uint64_t v;
+               strtoi_h_or_return(buf, v);
+
+               r = bch_flash_dev_create(c, v);
+               if (r)
+                       return r;
+       }
+
+       if (attr == &sysfs_clear_stats) {
+               atomic_long_set(&c->writeback_keys_done,        0);
+               atomic_long_set(&c->writeback_keys_failed,      0);
+
+               memset(&c->gc_stats, 0, sizeof(struct gc_stat));
+               bch_cache_accounting_clear(&c->accounting);
+       }
+
+       if (attr == &sysfs_trigger_gc)
+               wake_up_gc(c);
+
+       if (attr == &sysfs_prune_cache) {
+               struct shrink_control sc;
+               sc.gfp_mask = GFP_KERNEL;
+               sc.nr_to_scan = strtoul_or_return(buf);
+               c->shrink.scan_objects(&c->shrink, &sc);
+       }
+
+       sysfs_strtoul(congested_read_threshold_us,
+                     c->congested_read_threshold_us);
+       sysfs_strtoul(congested_write_threshold_us,
+                     c->congested_write_threshold_us);
+
+       if (attr == &sysfs_errors) {
+               ssize_t v = bch_read_string_list(buf, error_actions);
+
+               if (v < 0)
+                       return v;
+
+               c->on_error = v;
+       }
+
+       if (attr == &sysfs_io_error_limit)
+               c->error_limit = strtoul_or_return(buf) << IO_ERROR_SHIFT;
+
+       /* See count_io_errors() for why 88 */
+       if (attr == &sysfs_io_error_halflife)
+               c->error_decay = strtoul_or_return(buf) / 88;
+
+       sysfs_strtoul(journal_delay_ms,         c->journal_delay_ms);
+       sysfs_strtoul(verify,                   c->verify);
+       sysfs_strtoul(key_merging_disabled,     c->key_merging_disabled);
+       sysfs_strtoul(expensive_debug_checks,   c->expensive_debug_checks);
+       sysfs_strtoul(gc_always_rewrite,        c->gc_always_rewrite);
+       sysfs_strtoul(btree_shrinker_disabled,  c->shrinker_disabled);
+       sysfs_strtoul(copy_gc_enabled,          c->copy_gc_enabled);
+
+       return size;
+}
+STORE_LOCKED(bch_cache_set)
+
+SHOW(bch_cache_set_internal)
+{
+       struct cache_set *c = container_of(kobj, struct cache_set, internal);
+       return bch_cache_set_show(&c->kobj, attr, buf);
+}
+
+STORE(bch_cache_set_internal)
+{
+       struct cache_set *c = container_of(kobj, struct cache_set, internal);
+       return bch_cache_set_store(&c->kobj, attr, buf, size);
+}
+
+static void bch_cache_set_internal_release(struct kobject *k)
+{
+}
+
+static struct attribute *bch_cache_set_files[] = {
+       &sysfs_unregister,
+       &sysfs_stop,
+       &sysfs_synchronous,
+       &sysfs_journal_delay_ms,
+       &sysfs_flash_vol_create,
+
+       &sysfs_bucket_size,
+       &sysfs_block_size,
+       &sysfs_tree_depth,
+       &sysfs_root_usage_percent,
+       &sysfs_btree_cache_size,
+       &sysfs_cache_available_percent,
+
+       &sysfs_average_key_size,
+
+       &sysfs_errors,
+       &sysfs_io_error_limit,
+       &sysfs_io_error_halflife,
+       &sysfs_congested,
+       &sysfs_congested_read_threshold_us,
+       &sysfs_congested_write_threshold_us,
+       &sysfs_clear_stats,
+       NULL
+};
+KTYPE(bch_cache_set);
+
+static struct attribute *bch_cache_set_internal_files[] = {
+       &sysfs_active_journal_entries,
+
+       sysfs_time_stats_attribute_list(btree_gc, sec, ms)
+       sysfs_time_stats_attribute_list(btree_split, sec, us)
+       sysfs_time_stats_attribute_list(btree_sort, ms, us)
+       sysfs_time_stats_attribute_list(btree_read, ms, us)
+
+       &sysfs_btree_nodes,
+       &sysfs_btree_used_percent,
+       &sysfs_btree_cache_max_chain,
+
+       &sysfs_bset_tree_stats,
+       &sysfs_cache_read_races,
+       &sysfs_writeback_keys_done,
+       &sysfs_writeback_keys_failed,
+
+       &sysfs_trigger_gc,
+       &sysfs_prune_cache,
+#ifdef CONFIG_BCACHE_DEBUG
+       &sysfs_verify,
+       &sysfs_key_merging_disabled,
+       &sysfs_expensive_debug_checks,
+#endif
+       &sysfs_gc_always_rewrite,
+       &sysfs_btree_shrinker_disabled,
+       &sysfs_copy_gc_enabled,
+       NULL
+};
+KTYPE(bch_cache_set_internal);
+
+SHOW(__bch_cache)
+{
+       struct cache *ca = container_of(kobj, struct cache, kobj);
+
+       sysfs_hprint(bucket_size,       bucket_bytes(ca));
+       sysfs_hprint(block_size,        block_bytes(ca));
+       sysfs_print(nbuckets,           ca->sb.nbuckets);
+       sysfs_print(discard,            ca->discard);
+       sysfs_hprint(written, atomic_long_read(&ca->sectors_written) << 9);
+       sysfs_hprint(btree_written,
+                    atomic_long_read(&ca->btree_sectors_written) << 9);
+       sysfs_hprint(metadata_written,
+                    (atomic_long_read(&ca->meta_sectors_written) +
+                     atomic_long_read(&ca->btree_sectors_written)) << 9);
+
+       sysfs_print(io_errors,
+                   atomic_read(&ca->io_errors) >> IO_ERROR_SHIFT);
+
+       if (attr == &sysfs_cache_replacement_policy)
+               return bch_snprint_string_list(buf, PAGE_SIZE,
+                                              cache_replacement_policies,
+                                              CACHE_REPLACEMENT(&ca->sb));
+
+       if (attr == &sysfs_priority_stats) {
+               int cmp(const void *l, const void *r)
+               {       return *((uint16_t *) r) - *((uint16_t *) l); }
+
+               struct bucket *b;
+               size_t n = ca->sb.nbuckets, i;
+               size_t unused = 0, available = 0, dirty = 0, meta = 0;
+               uint64_t sum = 0;
+               /* Compute 31 quantiles */
+               uint16_t q[31], *p, *cached;
+               ssize_t ret;
+
+               cached = p = vmalloc(ca->sb.nbuckets * sizeof(uint16_t));
+               if (!p)
+                       return -ENOMEM;
+
+               mutex_lock(&ca->set->bucket_lock);
+               for_each_bucket(b, ca) {
+                       if (!GC_SECTORS_USED(b))
+                               unused++;
+                       if (GC_MARK(b) == GC_MARK_RECLAIMABLE)
+                               available++;
+                       if (GC_MARK(b) == GC_MARK_DIRTY)
+                               dirty++;
+                       if (GC_MARK(b) == GC_MARK_METADATA)
+                               meta++;
+               }
+
+               for (i = ca->sb.first_bucket; i < n; i++)
+                       p[i] = ca->buckets[i].prio;
+               mutex_unlock(&ca->set->bucket_lock);
+
+               sort(p, n, sizeof(uint16_t), cmp, NULL);
+
+               while (n &&
+                      !cached[n - 1])
+                       --n;
+
+               unused = ca->sb.nbuckets - n;
+
+               while (cached < p + n &&
+                      *cached == BTREE_PRIO)
+                       cached++, n--;
+
+               for (i = 0; i < n; i++)
+                       sum += INITIAL_PRIO - cached[i];
+
+               if (n)
+                       do_div(sum, n);
+
+               for (i = 0; i < ARRAY_SIZE(q); i++)
+                       q[i] = INITIAL_PRIO - cached[n * (i + 1) /
+                               (ARRAY_SIZE(q) + 1)];
+
+               vfree(p);
+
+               ret = scnprintf(buf, PAGE_SIZE,
+                               "Unused:                %zu%%\n"
+                               "Clean:         %zu%%\n"
+                               "Dirty:         %zu%%\n"
+                               "Metadata:      %zu%%\n"
+                               "Average:       %llu\n"
+                               "Sectors per Q: %zu\n"
+                               "Quantiles:     [",
+                               unused * 100 / (size_t) ca->sb.nbuckets,
+                               available * 100 / (size_t) ca->sb.nbuckets,
+                               dirty * 100 / (size_t) ca->sb.nbuckets,
+                               meta * 100 / (size_t) ca->sb.nbuckets, sum,
+                               n * ca->sb.bucket_size / (ARRAY_SIZE(q) + 1));
+
+               for (i = 0; i < ARRAY_SIZE(q); i++)
+                       ret += scnprintf(buf + ret, PAGE_SIZE - ret,
+                                        "%u ", q[i]);
+               ret--;
+
+               ret += scnprintf(buf + ret, PAGE_SIZE - ret, "]\n");
+
+               return ret;
+       }
+
+       return 0;
+}
+SHOW_LOCKED(bch_cache)
+
+STORE(__bch_cache)
+{
+       struct cache *ca = container_of(kobj, struct cache, kobj);
+
+       if (attr == &sysfs_discard) {
+               bool v = strtoul_or_return(buf);
+
+               if (blk_queue_discard(bdev_get_queue(ca->bdev)))
+                       ca->discard = v;
+
+               if (v != CACHE_DISCARD(&ca->sb)) {
+                       SET_CACHE_DISCARD(&ca->sb, v);
+                       bcache_write_super(ca->set);
+               }
+       }
+
+       if (attr == &sysfs_cache_replacement_policy) {
+               ssize_t v = bch_read_string_list(buf, cache_replacement_policies);
+
+               if (v < 0)
+                       return v;
+
+               if ((unsigned) v != CACHE_REPLACEMENT(&ca->sb)) {
+                       mutex_lock(&ca->set->bucket_lock);
+                       SET_CACHE_REPLACEMENT(&ca->sb, v);
+                       mutex_unlock(&ca->set->bucket_lock);
+
+                       bcache_write_super(ca->set);
+               }
+       }
+
+       if (attr == &sysfs_clear_stats) {
+               atomic_long_set(&ca->sectors_written, 0);
+               atomic_long_set(&ca->btree_sectors_written, 0);
+               atomic_long_set(&ca->meta_sectors_written, 0);
+               atomic_set(&ca->io_count, 0);
+               atomic_set(&ca->io_errors, 0);
+       }
+
+       return size;
+}
+STORE_LOCKED(bch_cache)
+
+static struct attribute *bch_cache_files[] = {
+       &sysfs_bucket_size,
+       &sysfs_block_size,
+       &sysfs_nbuckets,
+       &sysfs_priority_stats,
+       &sysfs_discard,
+       &sysfs_written,
+       &sysfs_btree_written,
+       &sysfs_metadata_written,
+       &sysfs_io_errors,
+       &sysfs_clear_stats,
+       &sysfs_cache_replacement_policy,
+       NULL
+};
+KTYPE(bch_cache);