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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef _BCACHEFS_H3#define _BCACHEFS_H4 5/*6 * SOME HIGH LEVEL CODE DOCUMENTATION:7 *8 * Bcache mostly works with cache sets, cache devices, and backing devices.9 *10 * Support for multiple cache devices hasn't quite been finished off yet, but11 * it's about 95% plumbed through. A cache set and its cache devices is sort of12 * like a md raid array and its component devices. Most of the code doesn't care13 * about individual cache devices, the main abstraction is the cache set.14 *15 * Multiple cache devices is intended to give us the ability to mirror dirty16 * cached data and metadata, without mirroring clean cached data.17 *18 * Backing devices are different, in that they have a lifetime independent of a19 * cache set. When you register a newly formatted backing device it'll come up20 * in passthrough mode, and then you can attach and detach a backing device from21 * a cache set at runtime - while it's mounted and in use. Detaching implicitly22 * invalidates any cached data for that backing device.23 *24 * A cache set can have multiple (many) backing devices attached to it.25 *26 * There's also flash only volumes - this is the reason for the distinction27 * between struct cached_dev and struct bcache_device. A flash only volume28 * works much like a bcache device that has a backing device, except the29 * "cached" data is always dirty. The end result is that we get thin30 * provisioning with very little additional code.31 *32 * Flash only volumes work but they're not production ready because the moving33 * garbage collector needs more work. More on that later.34 *35 * BUCKETS/ALLOCATION:36 *37 * Bcache is primarily designed for caching, which means that in normal38 * operation all of our available space will be allocated. Thus, we need an39 * efficient way of deleting things from the cache so we can write new things to40 * it.41 *42 * To do this, we first divide the cache device up into buckets. A bucket is the43 * unit of allocation; they're typically around 1 mb - anywhere from 128k to 2M+44 * works efficiently.45 *46 * Each bucket has a 16 bit priority, and an 8 bit generation associated with47 * it. The gens and priorities for all the buckets are stored contiguously and48 * packed on disk (in a linked list of buckets - aside from the superblock, all49 * of bcache's metadata is stored in buckets).50 *51 * The priority is used to implement an LRU. We reset a bucket's priority when52 * we allocate it or on cache it, and every so often we decrement the priority53 * of each bucket. It could be used to implement something more sophisticated,54 * if anyone ever gets around to it.55 *56 * The generation is used for invalidating buckets. Each pointer also has an 857 * bit generation embedded in it; for a pointer to be considered valid, its gen58 * must match the gen of the bucket it points into. Thus, to reuse a bucket all59 * we have to do is increment its gen (and write its new gen to disk; we batch60 * this up).61 *62 * Bcache is entirely COW - we never write twice to a bucket, even buckets that63 * contain metadata (including btree nodes).64 *65 * THE BTREE:66 *67 * Bcache is in large part design around the btree.68 *69 * At a high level, the btree is just an index of key -> ptr tuples.70 *71 * Keys represent extents, and thus have a size field. Keys also have a variable72 * number of pointers attached to them (potentially zero, which is handy for73 * invalidating the cache).74 *75 * The key itself is an inode:offset pair. The inode number corresponds to a76 * backing device or a flash only volume. The offset is the ending offset of the77 * extent within the inode - not the starting offset; this makes lookups78 * slightly more convenient.79 *80 * Pointers contain the cache device id, the offset on that device, and an 8 bit81 * generation number. More on the gen later.82 *83 * Index lookups are not fully abstracted - cache lookups in particular are84 * still somewhat mixed in with the btree code, but things are headed in that85 * direction.86 *87 * Updates are fairly well abstracted, though. There are two different ways of88 * updating the btree; insert and replace.89 *90 * BTREE_INSERT will just take a list of keys and insert them into the btree -91 * overwriting (possibly only partially) any extents they overlap with. This is92 * used to update the index after a write.93 *94 * BTREE_REPLACE is really cmpxchg(); it inserts a key into the btree iff it is95 * overwriting a key that matches another given key. This is used for inserting96 * data into the cache after a cache miss, and for background writeback, and for97 * the moving garbage collector.98 *99 * There is no "delete" operation; deleting things from the index is100 * accomplished by either by invalidating pointers (by incrementing a bucket's101 * gen) or by inserting a key with 0 pointers - which will overwrite anything102 * previously present at that location in the index.103 *104 * This means that there are always stale/invalid keys in the btree. They're105 * filtered out by the code that iterates through a btree node, and removed when106 * a btree node is rewritten.107 *108 * BTREE NODES:109 *110 * Our unit of allocation is a bucket, and we can't arbitrarily allocate and111 * free smaller than a bucket - so, that's how big our btree nodes are.112 *113 * (If buckets are really big we'll only use part of the bucket for a btree node114 * - no less than 1/4th - but a bucket still contains no more than a single115 * btree node. I'd actually like to change this, but for now we rely on the116 * bucket's gen for deleting btree nodes when we rewrite/split a node.)117 *118 * Anyways, btree nodes are big - big enough to be inefficient with a textbook119 * btree implementation.120 *121 * The way this is solved is that btree nodes are internally log structured; we122 * can append new keys to an existing btree node without rewriting it. This123 * means each set of keys we write is sorted, but the node is not.124 *125 * We maintain this log structure in memory - keeping 1Mb of keys sorted would126 * be expensive, and we have to distinguish between the keys we have written and127 * the keys we haven't. So to do a lookup in a btree node, we have to search128 * each sorted set. But we do merge written sets together lazily, so the cost of129 * these extra searches is quite low (normally most of the keys in a btree node130 * will be in one big set, and then there'll be one or two sets that are much131 * smaller).132 *133 * This log structure makes bcache's btree more of a hybrid between a134 * conventional btree and a compacting data structure, with some of the135 * advantages of both.136 *137 * GARBAGE COLLECTION:138 *139 * We can't just invalidate any bucket - it might contain dirty data or140 * metadata. If it once contained dirty data, other writes might overwrite it141 * later, leaving no valid pointers into that bucket in the index.142 *143 * Thus, the primary purpose of garbage collection is to find buckets to reuse.144 * It also counts how much valid data it each bucket currently contains, so that145 * allocation can reuse buckets sooner when they've been mostly overwritten.146 *147 * It also does some things that are really internal to the btree148 * implementation. If a btree node contains pointers that are stale by more than149 * some threshold, it rewrites the btree node to avoid the bucket's generation150 * wrapping around. It also merges adjacent btree nodes if they're empty enough.151 *152 * THE JOURNAL:153 *154 * Bcache's journal is not necessary for consistency; we always strictly155 * order metadata writes so that the btree and everything else is consistent on156 * disk in the event of an unclean shutdown, and in fact bcache had writeback157 * caching (with recovery from unclean shutdown) before journalling was158 * implemented.159 *160 * Rather, the journal is purely a performance optimization; we can't complete a161 * write until we've updated the index on disk, otherwise the cache would be162 * inconsistent in the event of an unclean shutdown. This means that without the163 * journal, on random write workloads we constantly have to update all the leaf164 * nodes in the btree, and those writes will be mostly empty (appending at most165 * a few keys each) - highly inefficient in terms of amount of metadata writes,166 * and it puts more strain on the various btree resorting/compacting code.167 *168 * The journal is just a log of keys we've inserted; on startup we just reinsert169 * all the keys in the open journal entries. That means that when we're updating170 * a node in the btree, we can wait until a 4k block of keys fills up before171 * writing them out.172 *173 * For simplicity, we only journal updates to leaf nodes; updates to parent174 * nodes are rare enough (since our leaf nodes are huge) that it wasn't worth175 * the complexity to deal with journalling them (in particular, journal replay)176 * - updates to non leaf nodes just happen synchronously (see btree_split()).177 */178 179#undef pr_fmt180#ifdef __KERNEL__181#define pr_fmt(fmt) "bcachefs: %s() " fmt "\n", __func__182#else183#define pr_fmt(fmt) "%s() " fmt "\n", __func__184#endif185 186#include <linux/backing-dev-defs.h>187#include <linux/bug.h>188#include <linux/bio.h>189#include <linux/closure.h>190#include <linux/kobject.h>191#include <linux/list.h>192#include <linux/math64.h>193#include <linux/mutex.h>194#include <linux/percpu-refcount.h>195#include <linux/percpu-rwsem.h>196#include <linux/refcount.h>197#include <linux/rhashtable.h>198#include <linux/rwsem.h>199#include <linux/semaphore.h>200#include <linux/seqlock.h>201#include <linux/shrinker.h>202#include <linux/srcu.h>203#include <linux/types.h>204#include <linux/workqueue.h>205#include <linux/zstd.h>206 207#include "bcachefs_format.h"208#include "disk_accounting_types.h"209#include "errcode.h"210#include "fifo.h"211#include "nocow_locking_types.h"212#include "opts.h"213#include "recovery_passes_types.h"214#include "sb-errors_types.h"215#include "seqmutex.h"216#include "time_stats.h"217#include "util.h"218 219#ifdef CONFIG_BCACHEFS_DEBUG220#define BCH_WRITE_REF_DEBUG221#endif222 223#ifndef dynamic_fault224#define dynamic_fault(...) 0225#endif226 227#define race_fault(...) dynamic_fault("bcachefs:race")228 229#define count_event(_c, _name) this_cpu_inc((_c)->counters[BCH_COUNTER_##_name])230 231#define trace_and_count(_c, _name, ...) \232do { \233 count_event(_c, _name); \234 trace_##_name(__VA_ARGS__); \235} while (0)236 237#define bch2_fs_init_fault(name) \238 dynamic_fault("bcachefs:bch_fs_init:" name)239#define bch2_meta_read_fault(name) \240 dynamic_fault("bcachefs:meta:read:" name)241#define bch2_meta_write_fault(name) \242 dynamic_fault("bcachefs:meta:write:" name)243 244#ifdef __KERNEL__245#define BCACHEFS_LOG_PREFIX246#endif247 248#ifdef BCACHEFS_LOG_PREFIX249 250#define bch2_log_msg(_c, fmt) "bcachefs (%s): " fmt, ((_c)->name)251#define bch2_fmt_dev(_ca, fmt) "bcachefs (%s): " fmt "\n", ((_ca)->name)252#define bch2_fmt_dev_offset(_ca, _offset, fmt) "bcachefs (%s sector %llu): " fmt "\n", ((_ca)->name), (_offset)253#define bch2_fmt_inum(_c, _inum, fmt) "bcachefs (%s inum %llu): " fmt "\n", ((_c)->name), (_inum)254#define bch2_fmt_inum_offset(_c, _inum, _offset, fmt) \255 "bcachefs (%s inum %llu offset %llu): " fmt "\n", ((_c)->name), (_inum), (_offset)256 257#else258 259#define bch2_log_msg(_c, fmt) fmt260#define bch2_fmt_dev(_ca, fmt) "%s: " fmt "\n", ((_ca)->name)261#define bch2_fmt_dev_offset(_ca, _offset, fmt) "%s sector %llu: " fmt "\n", ((_ca)->name), (_offset)262#define bch2_fmt_inum(_c, _inum, fmt) "inum %llu: " fmt "\n", (_inum)263#define bch2_fmt_inum_offset(_c, _inum, _offset, fmt) \264 "inum %llu offset %llu: " fmt "\n", (_inum), (_offset)265 266#endif267 268#define bch2_fmt(_c, fmt) bch2_log_msg(_c, fmt "\n")269 270void bch2_print_str(struct bch_fs *, const char *);271 272__printf(2, 3)273void bch2_print_opts(struct bch_opts *, const char *, ...);274 275__printf(2, 3)276void __bch2_print(struct bch_fs *c, const char *fmt, ...);277 278#define maybe_dev_to_fs(_c) _Generic((_c), \279 struct bch_dev *: ((struct bch_dev *) (_c))->fs, \280 struct bch_fs *: (_c))281 282#define bch2_print(_c, ...) __bch2_print(maybe_dev_to_fs(_c), __VA_ARGS__)283 284#define bch2_print_ratelimited(_c, ...) \285do { \286 static DEFINE_RATELIMIT_STATE(_rs, \287 DEFAULT_RATELIMIT_INTERVAL, \288 DEFAULT_RATELIMIT_BURST); \289 \290 if (__ratelimit(&_rs)) \291 bch2_print(_c, __VA_ARGS__); \292} while (0)293 294#define bch_info(c, fmt, ...) \295 bch2_print(c, KERN_INFO bch2_fmt(c, fmt), ##__VA_ARGS__)296#define bch_notice(c, fmt, ...) \297 bch2_print(c, KERN_NOTICE bch2_fmt(c, fmt), ##__VA_ARGS__)298#define bch_warn(c, fmt, ...) \299 bch2_print(c, KERN_WARNING bch2_fmt(c, fmt), ##__VA_ARGS__)300#define bch_warn_ratelimited(c, fmt, ...) \301 bch2_print_ratelimited(c, KERN_WARNING bch2_fmt(c, fmt), ##__VA_ARGS__)302 303#define bch_err(c, fmt, ...) \304 bch2_print(c, KERN_ERR bch2_fmt(c, fmt), ##__VA_ARGS__)305#define bch_err_dev(ca, fmt, ...) \306 bch2_print(c, KERN_ERR bch2_fmt_dev(ca, fmt), ##__VA_ARGS__)307#define bch_err_dev_offset(ca, _offset, fmt, ...) \308 bch2_print(c, KERN_ERR bch2_fmt_dev_offset(ca, _offset, fmt), ##__VA_ARGS__)309#define bch_err_inum(c, _inum, fmt, ...) \310 bch2_print(c, KERN_ERR bch2_fmt_inum(c, _inum, fmt), ##__VA_ARGS__)311#define bch_err_inum_offset(c, _inum, _offset, fmt, ...) \312 bch2_print(c, KERN_ERR bch2_fmt_inum_offset(c, _inum, _offset, fmt), ##__VA_ARGS__)313 314#define bch_err_ratelimited(c, fmt, ...) \315 bch2_print_ratelimited(c, KERN_ERR bch2_fmt(c, fmt), ##__VA_ARGS__)316#define bch_err_dev_ratelimited(ca, fmt, ...) \317 bch2_print_ratelimited(ca, KERN_ERR bch2_fmt_dev(ca, fmt), ##__VA_ARGS__)318#define bch_err_dev_offset_ratelimited(ca, _offset, fmt, ...) \319 bch2_print_ratelimited(ca, KERN_ERR bch2_fmt_dev_offset(ca, _offset, fmt), ##__VA_ARGS__)320#define bch_err_inum_ratelimited(c, _inum, fmt, ...) \321 bch2_print_ratelimited(c, KERN_ERR bch2_fmt_inum(c, _inum, fmt), ##__VA_ARGS__)322#define bch_err_inum_offset_ratelimited(c, _inum, _offset, fmt, ...) \323 bch2_print_ratelimited(c, KERN_ERR bch2_fmt_inum_offset(c, _inum, _offset, fmt), ##__VA_ARGS__)324 325static inline bool should_print_err(int err)326{327 return err && !bch2_err_matches(err, BCH_ERR_transaction_restart);328}329 330#define bch_err_fn(_c, _ret) \331do { \332 if (should_print_err(_ret)) \333 bch_err(_c, "%s(): error %s", __func__, bch2_err_str(_ret));\334} while (0)335 336#define bch_err_fn_ratelimited(_c, _ret) \337do { \338 if (should_print_err(_ret)) \339 bch_err_ratelimited(_c, "%s(): error %s", __func__, bch2_err_str(_ret));\340} while (0)341 342#define bch_err_msg(_c, _ret, _msg, ...) \343do { \344 if (should_print_err(_ret)) \345 bch_err(_c, "%s(): error " _msg " %s", __func__, \346 ##__VA_ARGS__, bch2_err_str(_ret)); \347} while (0)348 349#define bch_verbose(c, fmt, ...) \350do { \351 if ((c)->opts.verbose) \352 bch_info(c, fmt, ##__VA_ARGS__); \353} while (0)354 355#define pr_verbose_init(opts, fmt, ...) \356do { \357 if (opt_get(opts, verbose)) \358 pr_info(fmt, ##__VA_ARGS__); \359} while (0)360 361/* Parameters that are useful for debugging, but should always be compiled in: */362#define BCH_DEBUG_PARAMS_ALWAYS() \363 BCH_DEBUG_PARAM(key_merging_disabled, \364 "Disables merging of extents") \365 BCH_DEBUG_PARAM(btree_node_merging_disabled, \366 "Disables merging of btree nodes") \367 BCH_DEBUG_PARAM(btree_gc_always_rewrite, \368 "Causes mark and sweep to compact and rewrite every " \369 "btree node it traverses") \370 BCH_DEBUG_PARAM(btree_gc_rewrite_disabled, \371 "Disables rewriting of btree nodes during mark and sweep")\372 BCH_DEBUG_PARAM(btree_shrinker_disabled, \373 "Disables the shrinker callback for the btree node cache")\374 BCH_DEBUG_PARAM(verify_btree_ondisk, \375 "Reread btree nodes at various points to verify the " \376 "mergesort in the read path against modifications " \377 "done in memory") \378 BCH_DEBUG_PARAM(verify_all_btree_replicas, \379 "When reading btree nodes, read all replicas and " \380 "compare them") \381 BCH_DEBUG_PARAM(backpointers_no_use_write_buffer, \382 "Don't use the write buffer for backpointers, enabling "\383 "extra runtime checks")384 385/* Parameters that should only be compiled in debug mode: */386#define BCH_DEBUG_PARAMS_DEBUG() \387 BCH_DEBUG_PARAM(expensive_debug_checks, \388 "Enables various runtime debugging checks that " \389 "significantly affect performance") \390 BCH_DEBUG_PARAM(debug_check_iterators, \391 "Enables extra verification for btree iterators") \392 BCH_DEBUG_PARAM(debug_check_btree_accounting, \393 "Verify btree accounting for keys within a node") \394 BCH_DEBUG_PARAM(journal_seq_verify, \395 "Store the journal sequence number in the version " \396 "number of every btree key, and verify that btree " \397 "update ordering is preserved during recovery") \398 BCH_DEBUG_PARAM(inject_invalid_keys, \399 "Store the journal sequence number in the version " \400 "number of every btree key, and verify that btree " \401 "update ordering is preserved during recovery") \402 BCH_DEBUG_PARAM(test_alloc_startup, \403 "Force allocator startup to use the slowpath where it" \404 "can't find enough free buckets without invalidating" \405 "cached data") \406 BCH_DEBUG_PARAM(force_reconstruct_read, \407 "Force reads to use the reconstruct path, when reading" \408 "from erasure coded extents") \409 BCH_DEBUG_PARAM(test_restart_gc, \410 "Test restarting mark and sweep gc when bucket gens change")411 412#define BCH_DEBUG_PARAMS_ALL() BCH_DEBUG_PARAMS_ALWAYS() BCH_DEBUG_PARAMS_DEBUG()413 414#ifdef CONFIG_BCACHEFS_DEBUG415#define BCH_DEBUG_PARAMS() BCH_DEBUG_PARAMS_ALL()416#else417#define BCH_DEBUG_PARAMS() BCH_DEBUG_PARAMS_ALWAYS()418#endif419 420#define BCH_DEBUG_PARAM(name, description) extern bool bch2_##name;421BCH_DEBUG_PARAMS()422#undef BCH_DEBUG_PARAM423 424#ifndef CONFIG_BCACHEFS_DEBUG425#define BCH_DEBUG_PARAM(name, description) static const __maybe_unused bool bch2_##name;426BCH_DEBUG_PARAMS_DEBUG()427#undef BCH_DEBUG_PARAM428#endif429 430#define BCH_TIME_STATS() \431 x(btree_node_mem_alloc) \432 x(btree_node_split) \433 x(btree_node_compact) \434 x(btree_node_merge) \435 x(btree_node_sort) \436 x(btree_node_read) \437 x(btree_node_read_done) \438 x(btree_interior_update_foreground) \439 x(btree_interior_update_total) \440 x(btree_gc) \441 x(data_write) \442 x(data_read) \443 x(data_promote) \444 x(journal_flush_write) \445 x(journal_noflush_write) \446 x(journal_flush_seq) \447 x(blocked_journal_low_on_space) \448 x(blocked_journal_low_on_pin) \449 x(blocked_journal_max_in_flight) \450 x(blocked_key_cache_flush) \451 x(blocked_allocate) \452 x(blocked_allocate_open_bucket) \453 x(blocked_write_buffer_full) \454 x(nocow_lock_contended)455 456enum bch_time_stats {457#define x(name) BCH_TIME_##name,458 BCH_TIME_STATS()459#undef x460 BCH_TIME_STAT_NR461};462 463#include "alloc_types.h"464#include "btree_gc_types.h"465#include "btree_types.h"466#include "btree_node_scan_types.h"467#include "btree_write_buffer_types.h"468#include "buckets_types.h"469#include "buckets_waiting_for_journal_types.h"470#include "clock_types.h"471#include "disk_groups_types.h"472#include "ec_types.h"473#include "journal_types.h"474#include "keylist_types.h"475#include "quota_types.h"476#include "rebalance_types.h"477#include "replicas_types.h"478#include "sb-members_types.h"479#include "subvolume_types.h"480#include "super_types.h"481#include "thread_with_file_types.h"482 483/* Number of nodes btree coalesce will try to coalesce at once */484#define GC_MERGE_NODES 4U485 486/* Maximum number of nodes we might need to allocate atomically: */487#define BTREE_RESERVE_MAX (BTREE_MAX_DEPTH + (BTREE_MAX_DEPTH - 1))488 489/* Size of the freelist we allocate btree nodes from: */490#define BTREE_NODE_RESERVE (BTREE_RESERVE_MAX * 4)491 492#define BTREE_NODE_OPEN_BUCKET_RESERVE (BTREE_RESERVE_MAX * BCH_REPLICAS_MAX)493 494struct btree;495 496struct io_count {497 u64 sectors[2][BCH_DATA_NR];498};499 500struct discard_in_flight {501 bool in_progress:1;502 u64 bucket:63;503};504 505struct bch_dev {506 struct kobject kobj;507#ifdef CONFIG_BCACHEFS_DEBUG508 atomic_long_t ref;509 bool dying;510 unsigned long last_put;511#else512 struct percpu_ref ref;513#endif514 struct completion ref_completion;515 struct percpu_ref io_ref;516 struct completion io_ref_completion;517 518 struct bch_fs *fs;519 520 u8 dev_idx;521 /*522 * Cached version of this device's member info from superblock523 * Committed by bch2_write_super() -> bch_fs_mi_update()524 */525 struct bch_member_cpu mi;526 atomic64_t errors[BCH_MEMBER_ERROR_NR];527 528 __uuid_t uuid;529 char name[BDEVNAME_SIZE];530 531 struct bch_sb_handle disk_sb;532 struct bch_sb *sb_read_scratch;533 int sb_write_error;534 dev_t dev;535 atomic_t flush_seq;536 537 struct bch_devs_mask self;538 539 /*540 * Buckets:541 * Per-bucket arrays are protected by c->mark_lock, bucket_lock and542 * gc_gens_lock, for device resize - holding any is sufficient for543 * access: Or rcu_read_lock(), but only for dev_ptr_stale():544 */545 GENRADIX(struct bucket) buckets_gc;546 struct bucket_gens __rcu *bucket_gens;547 u8 *oldest_gen;548 unsigned long *buckets_nouse;549 struct rw_semaphore bucket_lock;550 551 struct bch_dev_usage __percpu *usage;552 553 /* Allocator: */554 u64 new_fs_bucket_idx;555 u64 alloc_cursor[3];556 557 unsigned nr_open_buckets;558 unsigned nr_partial_buckets;559 unsigned nr_btree_reserve;560 561 size_t inc_gen_needs_gc;562 size_t inc_gen_really_needs_gc;563 size_t buckets_waiting_on_journal;564 565 struct work_struct invalidate_work;566 struct work_struct discard_work;567 struct mutex discard_buckets_in_flight_lock;568 DARRAY(struct discard_in_flight) discard_buckets_in_flight;569 struct work_struct discard_fast_work;570 571 atomic64_t rebalance_work;572 573 struct journal_device journal;574 u64 prev_journal_sector;575 576 struct work_struct io_error_work;577 578 /* The rest of this all shows up in sysfs */579 atomic64_t cur_latency[2];580 struct bch2_time_stats_quantiles io_latency[2];581 582#define CONGESTED_MAX 1024583 atomic_t congested;584 u64 congested_last;585 586 struct io_count __percpu *io_done;587};588 589/*590 * initial_gc_unfixed591 * error592 * topology error593 */594 595#define BCH_FS_FLAGS() \596 x(new_fs) \597 x(started) \598 x(clean_recovery) \599 x(btree_running) \600 x(accounting_replay_done) \601 x(may_go_rw) \602 x(rw) \603 x(was_rw) \604 x(stopping) \605 x(emergency_ro) \606 x(going_ro) \607 x(write_disable_complete) \608 x(clean_shutdown) \609 x(fsck_running) \610 x(initial_gc_unfixed) \611 x(need_delete_dead_snapshots) \612 x(error) \613 x(topology_error) \614 x(errors_fixed) \615 x(errors_not_fixed) \616 x(no_invalid_checks)617 618enum bch_fs_flags {619#define x(n) BCH_FS_##n,620 BCH_FS_FLAGS()621#undef x622};623 624struct btree_debug {625 unsigned id;626};627 628#define BCH_TRANSACTIONS_NR 128629 630struct btree_transaction_stats {631 struct bch2_time_stats duration;632 struct bch2_time_stats lock_hold_times;633 struct mutex lock;634 unsigned nr_max_paths;635 unsigned journal_entries_size;636 unsigned max_mem;637 char *max_paths_text;638};639 640struct bch_fs_pcpu {641 u64 sectors_available;642};643 644struct journal_seq_blacklist_table {645 size_t nr;646 struct journal_seq_blacklist_table_entry {647 u64 start;648 u64 end;649 bool dirty;650 } entries[];651};652 653struct journal_keys {654 /* must match layout in darray_types.h */655 size_t nr, size;656 struct journal_key {657 u64 journal_seq;658 u32 journal_offset;659 enum btree_id btree_id:8;660 unsigned level:8;661 bool allocated;662 bool overwritten;663 struct bkey_i *k;664 } *data;665 /*666 * Gap buffer: instead of all the empty space in the array being at the667 * end of the buffer - from @nr to @size - the empty space is at @gap.668 * This means that sequential insertions are O(n) instead of O(n^2).669 */670 size_t gap;671 atomic_t ref;672 bool initial_ref_held;673};674 675struct btree_trans_buf {676 struct btree_trans *trans;677};678 679#define BCACHEFS_ROOT_SUBVOL_INUM \680 ((subvol_inum) { BCACHEFS_ROOT_SUBVOL, BCACHEFS_ROOT_INO })681 682#define BCH_WRITE_REFS() \683 x(trans) \684 x(write) \685 x(promote) \686 x(node_rewrite) \687 x(stripe_create) \688 x(stripe_delete) \689 x(reflink) \690 x(fallocate) \691 x(fsync) \692 x(dio_write) \693 x(discard) \694 x(discard_fast) \695 x(invalidate) \696 x(delete_dead_snapshots) \697 x(gc_gens) \698 x(snapshot_delete_pagecache) \699 x(sysfs) \700 x(btree_write_buffer)701 702enum bch_write_ref {703#define x(n) BCH_WRITE_REF_##n,704 BCH_WRITE_REFS()705#undef x706 BCH_WRITE_REF_NR,707};708 709struct bch_fs {710 struct closure cl;711 712 struct list_head list;713 struct kobject kobj;714 struct kobject counters_kobj;715 struct kobject internal;716 struct kobject opts_dir;717 struct kobject time_stats;718 unsigned long flags;719 720 int minor;721 struct device *chardev;722 struct super_block *vfs_sb;723 dev_t dev;724 char name[40];725 struct stdio_redirect *stdio;726 struct task_struct *stdio_filter;727 728 /* ro/rw, add/remove/resize devices: */729 struct rw_semaphore state_lock;730 731 /* Counts outstanding writes, for clean transition to read-only */732#ifdef BCH_WRITE_REF_DEBUG733 atomic_long_t writes[BCH_WRITE_REF_NR];734#else735 struct percpu_ref writes;736#endif737 /*738 * Analagous to c->writes, for asynchronous ops that don't necessarily739 * need fs to be read-write740 */741 refcount_t ro_ref;742 wait_queue_head_t ro_ref_wait;743 744 struct work_struct read_only_work;745 746 struct bch_dev __rcu *devs[BCH_SB_MEMBERS_MAX];747 748 struct bch_accounting_mem accounting;749 750 struct bch_replicas_cpu replicas;751 struct bch_replicas_cpu replicas_gc;752 struct mutex replicas_gc_lock;753 754 struct journal_entry_res btree_root_journal_res;755 struct journal_entry_res clock_journal_res;756 757 struct bch_disk_groups_cpu __rcu *disk_groups;758 759 struct bch_opts opts;760 761 /* Updated by bch2_sb_update():*/762 struct {763 __uuid_t uuid;764 __uuid_t user_uuid;765 766 u16 version;767 u16 version_min;768 u16 version_upgrade_complete;769 770 u8 nr_devices;771 u8 clean;772 773 u8 encryption_type;774 775 u64 time_base_lo;776 u32 time_base_hi;777 unsigned time_units_per_sec;778 unsigned nsec_per_time_unit;779 u64 features;780 u64 compat;781 unsigned long errors_silent[BITS_TO_LONGS(BCH_FSCK_ERR_MAX)];782 u64 btrees_lost_data;783 } sb;784 785 786 struct bch_sb_handle disk_sb;787 788 unsigned short block_bits; /* ilog2(block_size) */789 790 u16 btree_foreground_merge_threshold;791 792 struct closure sb_write;793 struct mutex sb_lock;794 795 /* snapshot.c: */796 struct snapshot_table __rcu *snapshots;797 struct mutex snapshot_table_lock;798 struct rw_semaphore snapshot_create_lock;799 800 struct work_struct snapshot_delete_work;801 struct work_struct snapshot_wait_for_pagecache_and_delete_work;802 snapshot_id_list snapshots_unlinked;803 struct mutex snapshots_unlinked_lock;804 805 /* BTREE CACHE */806 struct bio_set btree_bio;807 struct workqueue_struct *btree_read_complete_wq;808 struct workqueue_struct *btree_write_submit_wq;809 810 struct btree_root btree_roots_known[BTREE_ID_NR];811 DARRAY(struct btree_root) btree_roots_extra;812 struct mutex btree_root_lock;813 814 struct btree_cache btree_cache;815 816 /*817 * Cache of allocated btree nodes - if we allocate a btree node and818 * don't use it, if we free it that space can't be reused until going819 * _all_ the way through the allocator (which exposes us to a livelock820 * when allocating btree reserves fail halfway through) - instead, we821 * can stick them here:822 */823 struct btree_alloc btree_reserve_cache[BTREE_NODE_RESERVE * 2];824 unsigned btree_reserve_cache_nr;825 struct mutex btree_reserve_cache_lock;826 827 mempool_t btree_interior_update_pool;828 struct list_head btree_interior_update_list;829 struct list_head btree_interior_updates_unwritten;830 struct mutex btree_interior_update_lock;831 struct closure_waitlist btree_interior_update_wait;832 833 struct workqueue_struct *btree_interior_update_worker;834 struct work_struct btree_interior_update_work;835 836 struct workqueue_struct *btree_node_rewrite_worker;837 838 struct list_head pending_node_rewrites;839 struct mutex pending_node_rewrites_lock;840 841 /* btree_io.c: */842 spinlock_t btree_write_error_lock;843 struct btree_write_stats {844 atomic64_t nr;845 atomic64_t bytes;846 } btree_write_stats[BTREE_WRITE_TYPE_NR];847 848 /* btree_iter.c: */849 struct seqmutex btree_trans_lock;850 struct list_head btree_trans_list;851 mempool_t btree_trans_pool;852 mempool_t btree_trans_mem_pool;853 struct btree_trans_buf __percpu *btree_trans_bufs;854 855 struct srcu_struct btree_trans_barrier;856 bool btree_trans_barrier_initialized;857 858 struct btree_key_cache btree_key_cache;859 unsigned btree_key_cache_btrees;860 861 struct btree_write_buffer btree_write_buffer;862 863 struct workqueue_struct *btree_update_wq;864 struct workqueue_struct *btree_io_complete_wq;865 /* copygc needs its own workqueue for index updates.. */866 struct workqueue_struct *copygc_wq;867 /*868 * Use a dedicated wq for write ref holder tasks. Required to avoid869 * dependency problems with other wq tasks that can block on ref870 * draining, such as read-only transition.871 */872 struct workqueue_struct *write_ref_wq;873 874 /* ALLOCATION */875 struct bch_devs_mask rw_devs[BCH_DATA_NR];876 unsigned long rw_devs_change_count;877 878 u64 capacity; /* sectors */879 u64 reserved; /* sectors */880 881 /*882 * When capacity _decreases_ (due to a disk being removed), we883 * increment capacity_gen - this invalidates outstanding reservations884 * and forces them to be revalidated885 */886 u32 capacity_gen;887 unsigned bucket_size_max;888 889 atomic64_t sectors_available;890 struct mutex sectors_available_lock;891 892 struct bch_fs_pcpu __percpu *pcpu;893 894 struct percpu_rw_semaphore mark_lock;895 896 seqcount_t usage_lock;897 struct bch_fs_usage_base __percpu *usage;898 u64 __percpu *online_reserved;899 900 unsigned long allocator_last_stuck;901 902 struct io_clock io_clock[2];903 904 /* JOURNAL SEQ BLACKLIST */905 struct journal_seq_blacklist_table *906 journal_seq_blacklist_table;907 908 /* ALLOCATOR */909 spinlock_t freelist_lock;910 struct closure_waitlist freelist_wait;911 912 open_bucket_idx_t open_buckets_freelist;913 open_bucket_idx_t open_buckets_nr_free;914 struct closure_waitlist open_buckets_wait;915 struct open_bucket open_buckets[OPEN_BUCKETS_COUNT];916 open_bucket_idx_t open_buckets_hash[OPEN_BUCKETS_COUNT];917 918 open_bucket_idx_t open_buckets_partial[OPEN_BUCKETS_COUNT];919 open_bucket_idx_t open_buckets_partial_nr;920 921 struct write_point btree_write_point;922 struct write_point rebalance_write_point;923 924 struct write_point write_points[WRITE_POINT_MAX];925 struct hlist_head write_points_hash[WRITE_POINT_HASH_NR];926 struct mutex write_points_hash_lock;927 unsigned write_points_nr;928 929 struct buckets_waiting_for_journal buckets_waiting_for_journal;930 931 /* GARBAGE COLLECTION */932 struct work_struct gc_gens_work;933 unsigned long gc_count;934 935 enum btree_id gc_gens_btree;936 struct bpos gc_gens_pos;937 938 /*939 * Tracks GC's progress - everything in the range [ZERO_KEY..gc_cur_pos]940 * has been marked by GC.941 *942 * gc_cur_phase is a superset of btree_ids (BTREE_ID_extents etc.)943 *944 * Protected by gc_pos_lock. Only written to by GC thread, so GC thread945 * can read without a lock.946 */947 seqcount_t gc_pos_lock;948 struct gc_pos gc_pos;949 950 /*951 * The allocation code needs gc_mark in struct bucket to be correct, but952 * it's not while a gc is in progress.953 */954 struct rw_semaphore gc_lock;955 struct mutex gc_gens_lock;956 957 /* IO PATH */958 struct semaphore io_in_flight;959 struct bio_set bio_read;960 struct bio_set bio_read_split;961 struct bio_set bio_write;962 struct bio_set replica_set;963 struct mutex bio_bounce_pages_lock;964 mempool_t bio_bounce_pages;965 struct bucket_nocow_lock_table966 nocow_locks;967 struct rhashtable promote_table;968 969 mempool_t compression_bounce[2];970 mempool_t compress_workspace[BCH_COMPRESSION_TYPE_NR];971 mempool_t decompress_workspace;972 size_t zstd_workspace_size;973 974 struct crypto_shash *sha256;975 struct crypto_sync_skcipher *chacha20;976 struct crypto_shash *poly1305;977 978 atomic64_t key_version;979 980 mempool_t large_bkey_pool;981 982 /* MOVE.C */983 struct list_head moving_context_list;984 struct mutex moving_context_lock;985 986 /* REBALANCE */987 struct bch_fs_rebalance rebalance;988 989 /* COPYGC */990 struct task_struct *copygc_thread;991 struct write_point copygc_write_point;992 s64 copygc_wait_at;993 s64 copygc_wait;994 bool copygc_running;995 wait_queue_head_t copygc_running_wq;996 997 /* STRIPES: */998 GENRADIX(struct stripe) stripes;999 GENRADIX(struct gc_stripe) gc_stripes;1000 1001 struct hlist_head ec_stripes_new[32];1002 spinlock_t ec_stripes_new_lock;1003 1004 ec_stripes_heap ec_stripes_heap;1005 struct mutex ec_stripes_heap_lock;1006 1007 /* ERASURE CODING */1008 struct list_head ec_stripe_head_list;1009 struct mutex ec_stripe_head_lock;1010 1011 struct list_head ec_stripe_new_list;1012 struct mutex ec_stripe_new_lock;1013 wait_queue_head_t ec_stripe_new_wait;1014 1015 struct work_struct ec_stripe_create_work;1016 u64 ec_stripe_hint;1017 1018 struct work_struct ec_stripe_delete_work;1019 1020 struct bio_set ec_bioset;1021 1022 /* REFLINK */1023 reflink_gc_table reflink_gc_table;1024 size_t reflink_gc_nr;1025 1026 /* fs.c */1027 struct list_head vfs_inodes_list;1028 struct mutex vfs_inodes_lock;1029 struct rhashtable vfs_inodes_table;1030 1031 /* VFS IO PATH - fs-io.c */1032 struct bio_set writepage_bioset;1033 struct bio_set dio_write_bioset;1034 struct bio_set dio_read_bioset;1035 struct bio_set nocow_flush_bioset;1036 1037 /* QUOTAS */1038 struct bch_memquota_type quotas[QTYP_NR];1039 1040 /* RECOVERY */1041 u64 journal_replay_seq_start;1042 u64 journal_replay_seq_end;1043 /*1044 * Two different uses:1045 * "Has this fsck pass?" - i.e. should this type of error be an1046 * emergency read-only1047 * And, in certain situations fsck will rewind to an earlier pass: used1048 * for signaling to the toplevel code which pass we want to run now.1049 */1050 enum bch_recovery_pass curr_recovery_pass;1051 /* bitmask of recovery passes that we actually ran */1052 u64 recovery_passes_complete;1053 /* never rewinds version of curr_recovery_pass */1054 enum bch_recovery_pass recovery_pass_done;1055 struct semaphore online_fsck_mutex;1056 1057 /* DEBUG JUNK */1058 struct dentry *fs_debug_dir;1059 struct dentry *btree_debug_dir;1060 struct btree_debug btree_debug[BTREE_ID_NR];1061 struct btree *verify_data;1062 struct btree_node *verify_ondisk;1063 struct mutex verify_lock;1064 1065 u64 *unused_inode_hints;1066 unsigned inode_shard_bits;1067 1068 /*1069 * A btree node on disk could have too many bsets for an iterator to fit1070 * on the stack - have to dynamically allocate them1071 */1072 mempool_t fill_iter;1073 1074 mempool_t btree_bounce_pool;1075 1076 struct journal journal;1077 GENRADIX(struct journal_replay *) journal_entries;1078 u64 journal_entries_base_seq;1079 struct journal_keys journal_keys;1080 struct list_head journal_iters;1081 1082 struct find_btree_nodes found_btree_nodes;1083 1084 u64 last_bucket_seq_cleanup;1085 1086 u64 counters_on_mount[BCH_COUNTER_NR];1087 u64 __percpu *counters;1088 1089 unsigned copy_gc_enabled:1;1090 1091 struct bch2_time_stats times[BCH_TIME_STAT_NR];1092 1093 struct btree_transaction_stats btree_transaction_stats[BCH_TRANSACTIONS_NR];1094 1095 /* ERRORS */1096 struct list_head fsck_error_msgs;1097 struct mutex fsck_error_msgs_lock;1098 bool fsck_alloc_msgs_err;1099 1100 bch_sb_errors_cpu fsck_error_counts;1101 struct mutex fsck_error_counts_lock;1102};1103 1104extern struct wait_queue_head bch2_read_only_wait;1105 1106static inline void bch2_write_ref_get(struct bch_fs *c, enum bch_write_ref ref)1107{1108#ifdef BCH_WRITE_REF_DEBUG1109 atomic_long_inc(&c->writes[ref]);1110#else1111 percpu_ref_get(&c->writes);1112#endif1113}1114 1115static inline bool __bch2_write_ref_tryget(struct bch_fs *c, enum bch_write_ref ref)1116{1117#ifdef BCH_WRITE_REF_DEBUG1118 return !test_bit(BCH_FS_going_ro, &c->flags) &&1119 atomic_long_inc_not_zero(&c->writes[ref]);1120#else1121 return percpu_ref_tryget(&c->writes);1122#endif1123}1124 1125static inline bool bch2_write_ref_tryget(struct bch_fs *c, enum bch_write_ref ref)1126{1127#ifdef BCH_WRITE_REF_DEBUG1128 return !test_bit(BCH_FS_going_ro, &c->flags) &&1129 atomic_long_inc_not_zero(&c->writes[ref]);1130#else1131 return percpu_ref_tryget_live(&c->writes);1132#endif1133}1134 1135static inline void bch2_write_ref_put(struct bch_fs *c, enum bch_write_ref ref)1136{1137#ifdef BCH_WRITE_REF_DEBUG1138 long v = atomic_long_dec_return(&c->writes[ref]);1139 1140 BUG_ON(v < 0);1141 if (v)1142 return;1143 for (unsigned i = 0; i < BCH_WRITE_REF_NR; i++)1144 if (atomic_long_read(&c->writes[i]))1145 return;1146 1147 set_bit(BCH_FS_write_disable_complete, &c->flags);1148 wake_up(&bch2_read_only_wait);1149#else1150 percpu_ref_put(&c->writes);1151#endif1152}1153 1154static inline bool bch2_ro_ref_tryget(struct bch_fs *c)1155{1156 if (test_bit(BCH_FS_stopping, &c->flags))1157 return false;1158 1159 return refcount_inc_not_zero(&c->ro_ref);1160}1161 1162static inline void bch2_ro_ref_put(struct bch_fs *c)1163{1164 if (refcount_dec_and_test(&c->ro_ref))1165 wake_up(&c->ro_ref_wait);1166}1167 1168static inline void bch2_set_ra_pages(struct bch_fs *c, unsigned ra_pages)1169{1170#ifndef NO_BCACHEFS_FS1171 if (c->vfs_sb)1172 c->vfs_sb->s_bdi->ra_pages = ra_pages;1173#endif1174}1175 1176static inline unsigned bucket_bytes(const struct bch_dev *ca)1177{1178 return ca->mi.bucket_size << 9;1179}1180 1181static inline unsigned block_bytes(const struct bch_fs *c)1182{1183 return c->opts.block_size;1184}1185 1186static inline unsigned block_sectors(const struct bch_fs *c)1187{1188 return c->opts.block_size >> 9;1189}1190 1191static inline bool btree_id_cached(const struct bch_fs *c, enum btree_id btree)1192{1193 return c->btree_key_cache_btrees & (1U << btree);1194}1195 1196static inline struct timespec64 bch2_time_to_timespec(const struct bch_fs *c, s64 time)1197{1198 struct timespec64 t;1199 s64 sec;1200 s32 rem;1201 1202 time += c->sb.time_base_lo;1203 1204 sec = div_s64_rem(time, c->sb.time_units_per_sec, &rem);1205 1206 set_normalized_timespec64(&t, sec, rem * (s64)c->sb.nsec_per_time_unit);1207 1208 return t;1209}1210 1211static inline s64 timespec_to_bch2_time(const struct bch_fs *c, struct timespec64 ts)1212{1213 return (ts.tv_sec * c->sb.time_units_per_sec +1214 (int) ts.tv_nsec / c->sb.nsec_per_time_unit) - c->sb.time_base_lo;1215}1216 1217static inline s64 bch2_current_time(const struct bch_fs *c)1218{1219 struct timespec64 now;1220 1221 ktime_get_coarse_real_ts64(&now);1222 return timespec_to_bch2_time(c, now);1223}1224 1225static inline u64 bch2_current_io_time(const struct bch_fs *c, int rw)1226{1227 return max(1ULL, (u64) atomic64_read(&c->io_clock[rw].now) & LRU_TIME_MAX);1228}1229 1230static inline struct stdio_redirect *bch2_fs_stdio_redirect(struct bch_fs *c)1231{1232 struct stdio_redirect *stdio = c->stdio;1233 1234 if (c->stdio_filter && c->stdio_filter != current)1235 stdio = NULL;1236 return stdio;1237}1238 1239static inline unsigned metadata_replicas_required(struct bch_fs *c)1240{1241 return min(c->opts.metadata_replicas,1242 c->opts.metadata_replicas_required);1243}1244 1245static inline unsigned data_replicas_required(struct bch_fs *c)1246{1247 return min(c->opts.data_replicas,1248 c->opts.data_replicas_required);1249}1250 1251#define BKEY_PADDED_ONSTACK(key, pad) \1252 struct { struct bkey_i key; __u64 key ## _pad[pad]; }1253 1254#endif /* _BCACHEFS_H */1255