1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _BCACHEFS_H 3 #define _BCACHEFS_H 4 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, but 11 * it's about 95% plumbed through. A cache set and its cache devices is sort of 12 * like a md raid array and its component devices. Most of the code doesn't care 13 * 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 dirty 16 * cached data and metadata, without mirroring clean cached data. 17 * 18 * Backing devices are different, in that they have a lifetime independent of a 19 * cache set. When you register a newly formatted backing device it'll come up 20 * in passthrough mode, and then you can attach and detach a backing device from 21 * a cache set at runtime - while it's mounted and in use. Detaching implicitly 22 * 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 distinction 27 * between struct cached_dev and struct bcache_device. A flash only volume 28 * works much like a bcache device that has a backing device, except the 29 * "cached" data is always dirty. The end result is that we get thin 30 * provisioning with very little additional code. 31 * 32 * Flash only volumes work but they're not production ready because the moving 33 * 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 normal 38 * operation all of our available space will be allocated. Thus, we need an 39 * efficient way of deleting things from the cache so we can write new things to 40 * it. 41 * 42 * To do this, we first divide the cache device up into buckets. A bucket is the 43 * 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 with 47 * it. The gens and priorities for all the buckets are stored contiguously and 48 * packed on disk (in a linked list of buckets - aside from the superblock, all 49 * of bcache's metadata is stored in buckets). 50 * 51 * The priority is used to implement an LRU. We reset a bucket's priority when 52 * we allocate it or on cache it, and every so often we decrement the priority 53 * 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 8 57 * bit generation embedded in it; for a pointer to be considered valid, its gen 58 * must match the gen of the bucket it points into. Thus, to reuse a bucket all 59 * we have to do is increment its gen (and write its new gen to disk; we batch 60 * this up). 61 * 62 * Bcache is entirely COW - we never write twice to a bucket, even buckets that 63 * 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 variable 72 * number of pointers attached to them (potentially zero, which is handy for 73 * invalidating the cache). 74 * 75 * The key itself is an inode:offset pair. The inode number corresponds to a 76 * backing device or a flash only volume. The offset is the ending offset of the 77 * extent within the inode - not the starting offset; this makes lookups 78 * slightly more convenient. 79 * 80 * Pointers contain the cache device id, the offset on that device, and an 8 bit 81 * generation number. More on the gen later. 82 * 83 * Index lookups are not fully abstracted - cache lookups in particular are 84 * still somewhat mixed in with the btree code, but things are headed in that 85 * direction. 86 * 87 * Updates are fairly well abstracted, though. There are two different ways of 88 * 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 is 92 * used to update the index after a write. 93 * 94 * BTREE_REPLACE is really cmpxchg(); it inserts a key into the btree iff it is 95 * overwriting a key that matches another given key. This is used for inserting 96 * data into the cache after a cache miss, and for background writeback, and for 97 * the moving garbage collector. 98 * 99 * There is no "delete" operation; deleting things from the index is 100 * accomplished by either by invalidating pointers (by incrementing a bucket's 101 * gen) or by inserting a key with 0 pointers - which will overwrite anything 102 * previously present at that location in the index. 103 * 104 * This means that there are always stale/invalid keys in the btree. They're 105 * filtered out by the code that iterates through a btree node, and removed when 106 * a btree node is rewritten. 107 * 108 * BTREE NODES: 109 * 110 * Our unit of allocation is a bucket, and we can't arbitrarily allocate and 111 * 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 node 114 * - no less than 1/4th - but a bucket still contains no more than a single 115 * btree node. I'd actually like to change this, but for now we rely on the 116 * 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 textbook 119 * btree implementation. 120 * 121 * The way this is solved is that btree nodes are internally log structured; we 122 * can append new keys to an existing btree node without rewriting it. This 123 * 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 would 126 * be expensive, and we have to distinguish between the keys we have written and 127 * the keys we haven't. So to do a lookup in a btree node, we have to search 128 * each sorted set. But we do merge written sets together lazily, so the cost of 129 * these extra searches is quite low (normally most of the keys in a btree node 130 * will be in one big set, and then there'll be one or two sets that are much 131 * smaller). 132 * 133 * This log structure makes bcache's btree more of a hybrid between a 134 * conventional btree and a compacting data structure, with some of the 135 * advantages of both. 136 * 137 * GARBAGE COLLECTION: 138 * 139 * We can't just invalidate any bucket - it might contain dirty data or 140 * metadata. If it once contained dirty data, other writes might overwrite it 141 * 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 that 145 * allocation can reuse buckets sooner when they've been mostly overwritten. 146 * 147 * It also does some things that are really internal to the btree 148 * implementation. If a btree node contains pointers that are stale by more than 149 * some threshold, it rewrites the btree node to avoid the bucket's generation 150 * 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 strictly 155 * order metadata writes so that the btree and everything else is consistent on 156 * disk in the event of an unclean shutdown, and in fact bcache had writeback 157 * caching (with recovery from unclean shutdown) before journalling was 158 * implemented. 159 * 160 * Rather, the journal is purely a performance optimization; we can't complete a 161 * write until we've updated the index on disk, otherwise the cache would be 162 * inconsistent in the event of an unclean shutdown. This means that without the 163 * journal, on random write workloads we constantly have to update all the leaf 164 * nodes in the btree, and those writes will be mostly empty (appending at most 165 * 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 reinsert 169 * all the keys in the open journal entries. That means that when we're updating 170 * a node in the btree, we can wait until a 4k block of keys fills up before 171 * writing them out. 172 * 173 * For simplicity, we only journal updates to leaf nodes; updates to parent 174 * nodes are rare enough (since our leaf nodes are huge) that it wasn't worth 175 * 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_fmt 180 #ifdef __KERNEL__ 181 #define pr_fmt(fmt) "bcachefs: %s() " fmt "\n", __func__ 182 #else 183 #define pr_fmt(fmt) "%s() " fmt "\n", __func__ 184 #endif 185 186 #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/rhashtable.h> 197 #include <linux/rwsem.h> 198 #include <linux/semaphore.h> 199 #include <linux/seqlock.h> 200 #include <linux/shrinker.h> 201 #include <linux/srcu.h> 202 #include <linux/types.h> 203 #include <linux/workqueue.h> 204 #include <linux/zstd.h> 205 206 #include "bcachefs_format.h" 207 #include "errcode.h" 208 #include "fifo.h" 209 #include "nocow_locking_types.h" 210 #include "opts.h" 211 #include "recovery_types.h" 212 #include "seqmutex.h" 213 #include "util.h" 214 215 #ifdef CONFIG_BCACHEFS_DEBUG 216 #define BCH_WRITE_REF_DEBUG 217 #endif 218 219 #ifndef dynamic_fault 220 #define dynamic_fault(...) 0 221 #endif 222 223 #define race_fault(...) dynamic_fault("bcachefs:race") 224 225 #define trace_and_count(_c, _name, ...) \ 226 do { \ 227 this_cpu_inc((_c)->counters[BCH_COUNTER_##_name]); \ 228 trace_##_name(__VA_ARGS__); \ 229 } while (0) 230 231 #define bch2_fs_init_fault(name) \ 232 dynamic_fault("bcachefs:bch_fs_init:" name) 233 #define bch2_meta_read_fault(name) \ 234 dynamic_fault("bcachefs:meta:read:" name) 235 #define bch2_meta_write_fault(name) \ 236 dynamic_fault("bcachefs:meta:write:" name) 237 238 #ifdef __KERNEL__ 239 #define BCACHEFS_LOG_PREFIX 240 #endif 241 242 #ifdef BCACHEFS_LOG_PREFIX 243 244 #define bch2_log_msg(_c, fmt) "bcachefs (%s): " fmt, ((_c)->name) 245 #define bch2_fmt_dev(_ca, fmt) "bcachefs (%s): " fmt "\n", ((_ca)->name) 246 #define bch2_fmt_dev_offset(_ca, _offset, fmt) "bcachefs (%s sector %llu): " fmt "\n", ((_ca)->name), (_offset) 247 #define bch2_fmt_inum(_c, _inum, fmt) "bcachefs (%s inum %llu): " fmt "\n", ((_c)->name), (_inum) 248 #define bch2_fmt_inum_offset(_c, _inum, _offset, fmt) \ 249 "bcachefs (%s inum %llu offset %llu): " fmt "\n", ((_c)->name), (_inum), (_offset) 250 251 #else 252 253 #define bch2_log_msg(_c, fmt) fmt 254 #define bch2_fmt_dev(_ca, fmt) "%s: " fmt "\n", ((_ca)->name) 255 #define bch2_fmt_dev_offset(_ca, _offset, fmt) "%s sector %llu: " fmt "\n", ((_ca)->name), (_offset) 256 #define bch2_fmt_inum(_c, _inum, fmt) "inum %llu: " fmt "\n", (_inum) 257 #define bch2_fmt_inum_offset(_c, _inum, _offset, fmt) \ 258 "inum %llu offset %llu: " fmt "\n", (_inum), (_offset) 259 260 #endif 261 262 #define bch2_fmt(_c, fmt) bch2_log_msg(_c, fmt "\n") 263 264 #define bch_info(c, fmt, ...) \ 265 printk(KERN_INFO bch2_fmt(c, fmt), ##__VA_ARGS__) 266 #define bch_notice(c, fmt, ...) \ 267 printk(KERN_NOTICE bch2_fmt(c, fmt), ##__VA_ARGS__) 268 #define bch_warn(c, fmt, ...) \ 269 printk(KERN_WARNING bch2_fmt(c, fmt), ##__VA_ARGS__) 270 #define bch_warn_ratelimited(c, fmt, ...) \ 271 printk_ratelimited(KERN_WARNING bch2_fmt(c, fmt), ##__VA_ARGS__) 272 273 #define bch_err(c, fmt, ...) \ 274 printk(KERN_ERR bch2_fmt(c, fmt), ##__VA_ARGS__) 275 #define bch_err_dev(ca, fmt, ...) \ 276 printk(KERN_ERR bch2_fmt_dev(ca, fmt), ##__VA_ARGS__) 277 #define bch_err_dev_offset(ca, _offset, fmt, ...) \ 278 printk(KERN_ERR bch2_fmt_dev_offset(ca, _offset, fmt), ##__VA_ARGS__) 279 #define bch_err_inum(c, _inum, fmt, ...) \ 280 printk(KERN_ERR bch2_fmt_inum(c, _inum, fmt), ##__VA_ARGS__) 281 #define bch_err_inum_offset(c, _inum, _offset, fmt, ...) \ 282 printk(KERN_ERR bch2_fmt_inum_offset(c, _inum, _offset, fmt), ##__VA_ARGS__) 283 284 #define bch_err_ratelimited(c, fmt, ...) \ 285 printk_ratelimited(KERN_ERR bch2_fmt(c, fmt), ##__VA_ARGS__) 286 #define bch_err_dev_ratelimited(ca, fmt, ...) \ 287 printk_ratelimited(KERN_ERR bch2_fmt_dev(ca, fmt), ##__VA_ARGS__) 288 #define bch_err_dev_offset_ratelimited(ca, _offset, fmt, ...) \ 289 printk_ratelimited(KERN_ERR bch2_fmt_dev_offset(ca, _offset, fmt), ##__VA_ARGS__) 290 #define bch_err_inum_ratelimited(c, _inum, fmt, ...) \ 291 printk_ratelimited(KERN_ERR bch2_fmt_inum(c, _inum, fmt), ##__VA_ARGS__) 292 #define bch_err_inum_offset_ratelimited(c, _inum, _offset, fmt, ...) \ 293 printk_ratelimited(KERN_ERR bch2_fmt_inum_offset(c, _inum, _offset, fmt), ##__VA_ARGS__) 294 295 #define bch_err_fn(_c, _ret) \ 296 do { \ 297 if (_ret && !bch2_err_matches(_ret, BCH_ERR_transaction_restart))\ 298 bch_err(_c, "%s(): error %s", __func__, bch2_err_str(_ret));\ 299 } while (0) 300 301 #define bch_err_msg(_c, _ret, _msg, ...) \ 302 do { \ 303 if (_ret && !bch2_err_matches(_ret, BCH_ERR_transaction_restart))\ 304 bch_err(_c, "%s(): error " _msg " %s", __func__, \ 305 ##__VA_ARGS__, bch2_err_str(_ret)); \ 306 } while (0) 307 308 #define bch_verbose(c, fmt, ...) \ 309 do { \ 310 if ((c)->opts.verbose) \ 311 bch_info(c, fmt, ##__VA_ARGS__); \ 312 } while (0) 313 314 #define pr_verbose_init(opts, fmt, ...) \ 315 do { \ 316 if (opt_get(opts, verbose)) \ 317 pr_info(fmt, ##__VA_ARGS__); \ 318 } while (0) 319 320 /* Parameters that are useful for debugging, but should always be compiled in: */ 321 #define BCH_DEBUG_PARAMS_ALWAYS() \ 322 BCH_DEBUG_PARAM(key_merging_disabled, \ 323 "Disables merging of extents") \ 324 BCH_DEBUG_PARAM(btree_gc_always_rewrite, \ 325 "Causes mark and sweep to compact and rewrite every " \ 326 "btree node it traverses") \ 327 BCH_DEBUG_PARAM(btree_gc_rewrite_disabled, \ 328 "Disables rewriting of btree nodes during mark and sweep")\ 329 BCH_DEBUG_PARAM(btree_shrinker_disabled, \ 330 "Disables the shrinker callback for the btree node cache")\ 331 BCH_DEBUG_PARAM(verify_btree_ondisk, \ 332 "Reread btree nodes at various points to verify the " \ 333 "mergesort in the read path against modifications " \ 334 "done in memory") \ 335 BCH_DEBUG_PARAM(verify_all_btree_replicas, \ 336 "When reading btree nodes, read all replicas and " \ 337 "compare them") \ 338 BCH_DEBUG_PARAM(backpointers_no_use_write_buffer, \ 339 "Don't use the write buffer for backpointers, enabling "\ 340 "extra runtime checks") 341 342 /* Parameters that should only be compiled in debug mode: */ 343 #define BCH_DEBUG_PARAMS_DEBUG() \ 344 BCH_DEBUG_PARAM(expensive_debug_checks, \ 345 "Enables various runtime debugging checks that " \ 346 "significantly affect performance") \ 347 BCH_DEBUG_PARAM(debug_check_iterators, \ 348 "Enables extra verification for btree iterators") \ 349 BCH_DEBUG_PARAM(debug_check_btree_accounting, \ 350 "Verify btree accounting for keys within a node") \ 351 BCH_DEBUG_PARAM(journal_seq_verify, \ 352 "Store the journal sequence number in the version " \ 353 "number of every btree key, and verify that btree " \ 354 "update ordering is preserved during recovery") \ 355 BCH_DEBUG_PARAM(inject_invalid_keys, \ 356 "Store the journal sequence number in the version " \ 357 "number of every btree key, and verify that btree " \ 358 "update ordering is preserved during recovery") \ 359 BCH_DEBUG_PARAM(test_alloc_startup, \ 360 "Force allocator startup to use the slowpath where it" \ 361 "can't find enough free buckets without invalidating" \ 362 "cached data") \ 363 BCH_DEBUG_PARAM(force_reconstruct_read, \ 364 "Force reads to use the reconstruct path, when reading" \ 365 "from erasure coded extents") \ 366 BCH_DEBUG_PARAM(test_restart_gc, \ 367 "Test restarting mark and sweep gc when bucket gens change") 368 369 #define BCH_DEBUG_PARAMS_ALL() BCH_DEBUG_PARAMS_ALWAYS() BCH_DEBUG_PARAMS_DEBUG() 370 371 #ifdef CONFIG_BCACHEFS_DEBUG 372 #define BCH_DEBUG_PARAMS() BCH_DEBUG_PARAMS_ALL() 373 #else 374 #define BCH_DEBUG_PARAMS() BCH_DEBUG_PARAMS_ALWAYS() 375 #endif 376 377 #define BCH_DEBUG_PARAM(name, description) extern bool bch2_##name; 378 BCH_DEBUG_PARAMS() 379 #undef BCH_DEBUG_PARAM 380 381 #ifndef CONFIG_BCACHEFS_DEBUG 382 #define BCH_DEBUG_PARAM(name, description) static const __maybe_unused bool bch2_##name; 383 BCH_DEBUG_PARAMS_DEBUG() 384 #undef BCH_DEBUG_PARAM 385 #endif 386 387 #define BCH_TIME_STATS() \ 388 x(btree_node_mem_alloc) \ 389 x(btree_node_split) \ 390 x(btree_node_compact) \ 391 x(btree_node_merge) \ 392 x(btree_node_sort) \ 393 x(btree_node_read) \ 394 x(btree_interior_update_foreground) \ 395 x(btree_interior_update_total) \ 396 x(btree_gc) \ 397 x(data_write) \ 398 x(data_read) \ 399 x(data_promote) \ 400 x(journal_flush_write) \ 401 x(journal_noflush_write) \ 402 x(journal_flush_seq) \ 403 x(blocked_journal) \ 404 x(blocked_allocate) \ 405 x(blocked_allocate_open_bucket) \ 406 x(nocow_lock_contended) 407 408 enum bch_time_stats { 409 #define x(name) BCH_TIME_##name, 410 BCH_TIME_STATS() 411 #undef x 412 BCH_TIME_STAT_NR 413 }; 414 415 #include "alloc_types.h" 416 #include "btree_types.h" 417 #include "btree_write_buffer_types.h" 418 #include "buckets_types.h" 419 #include "buckets_waiting_for_journal_types.h" 420 #include "clock_types.h" 421 #include "ec_types.h" 422 #include "journal_types.h" 423 #include "keylist_types.h" 424 #include "quota_types.h" 425 #include "rebalance_types.h" 426 #include "replicas_types.h" 427 #include "subvolume_types.h" 428 #include "super_types.h" 429 430 /* Number of nodes btree coalesce will try to coalesce at once */ 431 #define GC_MERGE_NODES 4U 432 433 /* Maximum number of nodes we might need to allocate atomically: */ 434 #define BTREE_RESERVE_MAX (BTREE_MAX_DEPTH + (BTREE_MAX_DEPTH - 1)) 435 436 /* Size of the freelist we allocate btree nodes from: */ 437 #define BTREE_NODE_RESERVE (BTREE_RESERVE_MAX * 4) 438 439 #define BTREE_NODE_OPEN_BUCKET_RESERVE (BTREE_RESERVE_MAX * BCH_REPLICAS_MAX) 440 441 struct btree; 442 443 enum gc_phase { 444 GC_PHASE_NOT_RUNNING, 445 GC_PHASE_START, 446 GC_PHASE_SB, 447 448 GC_PHASE_BTREE_stripes, 449 GC_PHASE_BTREE_extents, 450 GC_PHASE_BTREE_inodes, 451 GC_PHASE_BTREE_dirents, 452 GC_PHASE_BTREE_xattrs, 453 GC_PHASE_BTREE_alloc, 454 GC_PHASE_BTREE_quotas, 455 GC_PHASE_BTREE_reflink, 456 GC_PHASE_BTREE_subvolumes, 457 GC_PHASE_BTREE_snapshots, 458 GC_PHASE_BTREE_lru, 459 GC_PHASE_BTREE_freespace, 460 GC_PHASE_BTREE_need_discard, 461 GC_PHASE_BTREE_backpointers, 462 GC_PHASE_BTREE_bucket_gens, 463 GC_PHASE_BTREE_snapshot_trees, 464 GC_PHASE_BTREE_deleted_inodes, 465 GC_PHASE_BTREE_logged_ops, 466 467 GC_PHASE_PENDING_DELETE, 468 }; 469 470 struct gc_pos { 471 enum gc_phase phase; 472 struct bpos pos; 473 unsigned level; 474 }; 475 476 struct reflink_gc { 477 u64 offset; 478 u32 size; 479 u32 refcount; 480 }; 481 482 typedef GENRADIX(struct reflink_gc) reflink_gc_table; 483 484 struct io_count { 485 u64 sectors[2][BCH_DATA_NR]; 486 }; 487 488 struct bch_dev { 489 struct kobject kobj; 490 struct percpu_ref ref; 491 struct completion ref_completion; 492 struct percpu_ref io_ref; 493 struct completion io_ref_completion; 494 495 struct bch_fs *fs; 496 497 u8 dev_idx; 498 /* 499 * Cached version of this device's member info from superblock 500 * Committed by bch2_write_super() -> bch_fs_mi_update() 501 */ 502 struct bch_member_cpu mi; 503 __uuid_t uuid; 504 char name[BDEVNAME_SIZE]; 505 506 struct bch_sb_handle disk_sb; 507 struct bch_sb *sb_read_scratch; 508 int sb_write_error; 509 dev_t dev; 510 atomic_t flush_seq; 511 512 struct bch_devs_mask self; 513 514 /* biosets used in cloned bios for writing multiple replicas */ 515 struct bio_set replica_set; 516 517 /* 518 * Buckets: 519 * Per-bucket arrays are protected by c->mark_lock, bucket_lock and 520 * gc_lock, for device resize - holding any is sufficient for access: 521 * Or rcu_read_lock(), but only for ptr_stale(): 522 */ 523 struct bucket_array __rcu *buckets_gc; 524 struct bucket_gens __rcu *bucket_gens; 525 u8 *oldest_gen; 526 unsigned long *buckets_nouse; 527 struct rw_semaphore bucket_lock; 528 529 struct bch_dev_usage *usage_base; 530 struct bch_dev_usage __percpu *usage[JOURNAL_BUF_NR]; 531 struct bch_dev_usage __percpu *usage_gc; 532 533 /* Allocator: */ 534 u64 new_fs_bucket_idx; 535 u64 alloc_cursor; 536 537 unsigned nr_open_buckets; 538 unsigned nr_btree_reserve; 539 540 size_t inc_gen_needs_gc; 541 size_t inc_gen_really_needs_gc; 542 size_t buckets_waiting_on_journal; 543 544 atomic64_t rebalance_work; 545 546 struct journal_device journal; 547 u64 prev_journal_sector; 548 549 struct work_struct io_error_work; 550 551 /* The rest of this all shows up in sysfs */ 552 atomic64_t cur_latency[2]; 553 struct bch2_time_stats io_latency[2]; 554 555 #define CONGESTED_MAX 1024 556 atomic_t congested; 557 u64 congested_last; 558 559 struct io_count __percpu *io_done; 560 }; 561 562 enum { 563 /* startup: */ 564 BCH_FS_STARTED, 565 BCH_FS_MAY_GO_RW, 566 BCH_FS_RW, 567 BCH_FS_WAS_RW, 568 569 /* shutdown: */ 570 BCH_FS_STOPPING, 571 BCH_FS_EMERGENCY_RO, 572 BCH_FS_GOING_RO, 573 BCH_FS_WRITE_DISABLE_COMPLETE, 574 BCH_FS_CLEAN_SHUTDOWN, 575 576 /* fsck passes: */ 577 BCH_FS_FSCK_DONE, 578 BCH_FS_INITIAL_GC_UNFIXED, /* kill when we enumerate fsck errors */ 579 BCH_FS_NEED_ANOTHER_GC, 580 581 BCH_FS_HAVE_DELETED_SNAPSHOTS, 582 583 /* errors: */ 584 BCH_FS_ERROR, 585 BCH_FS_TOPOLOGY_ERROR, 586 BCH_FS_ERRORS_FIXED, 587 BCH_FS_ERRORS_NOT_FIXED, 588 }; 589 590 struct btree_debug { 591 unsigned id; 592 }; 593 594 #define BCH_TRANSACTIONS_NR 128 595 596 struct btree_transaction_stats { 597 struct bch2_time_stats lock_hold_times; 598 struct mutex lock; 599 unsigned nr_max_paths; 600 unsigned wb_updates_size; 601 unsigned max_mem; 602 char *max_paths_text; 603 }; 604 605 struct bch_fs_pcpu { 606 u64 sectors_available; 607 }; 608 609 struct journal_seq_blacklist_table { 610 size_t nr; 611 struct journal_seq_blacklist_table_entry { 612 u64 start; 613 u64 end; 614 bool dirty; 615 } entries[0]; 616 }; 617 618 struct journal_keys { 619 struct journal_key { 620 u64 journal_seq; 621 u32 journal_offset; 622 enum btree_id btree_id:8; 623 unsigned level:8; 624 bool allocated; 625 bool overwritten; 626 struct bkey_i *k; 627 } *d; 628 /* 629 * Gap buffer: instead of all the empty space in the array being at the 630 * end of the buffer - from @nr to @size - the empty space is at @gap. 631 * This means that sequential insertions are O(n) instead of O(n^2). 632 */ 633 size_t gap; 634 size_t nr; 635 size_t size; 636 }; 637 638 struct btree_trans_buf { 639 struct btree_trans *trans; 640 }; 641 642 #define REPLICAS_DELTA_LIST_MAX (1U << 16) 643 644 #define BCACHEFS_ROOT_SUBVOL_INUM \ 645 ((subvol_inum) { BCACHEFS_ROOT_SUBVOL, BCACHEFS_ROOT_INO }) 646 647 #define BCH_WRITE_REFS() \ 648 x(trans) \ 649 x(write) \ 650 x(promote) \ 651 x(node_rewrite) \ 652 x(stripe_create) \ 653 x(stripe_delete) \ 654 x(reflink) \ 655 x(fallocate) \ 656 x(discard) \ 657 x(invalidate) \ 658 x(delete_dead_snapshots) \ 659 x(snapshot_delete_pagecache) \ 660 x(sysfs) 661 662 enum bch_write_ref { 663 #define x(n) BCH_WRITE_REF_##n, 664 BCH_WRITE_REFS() 665 #undef x 666 BCH_WRITE_REF_NR, 667 }; 668 669 struct bch_fs { 670 struct closure cl; 671 672 struct list_head list; 673 struct kobject kobj; 674 struct kobject counters_kobj; 675 struct kobject internal; 676 struct kobject opts_dir; 677 struct kobject time_stats; 678 unsigned long flags; 679 680 int minor; 681 struct device *chardev; 682 struct super_block *vfs_sb; 683 dev_t dev; 684 char name[40]; 685 686 /* ro/rw, add/remove/resize devices: */ 687 struct rw_semaphore state_lock; 688 689 /* Counts outstanding writes, for clean transition to read-only */ 690 #ifdef BCH_WRITE_REF_DEBUG 691 atomic_long_t writes[BCH_WRITE_REF_NR]; 692 #else 693 struct percpu_ref writes; 694 #endif 695 struct work_struct read_only_work; 696 697 struct bch_dev __rcu *devs[BCH_SB_MEMBERS_MAX]; 698 699 struct bch_replicas_cpu replicas; 700 struct bch_replicas_cpu replicas_gc; 701 struct mutex replicas_gc_lock; 702 mempool_t replicas_delta_pool; 703 704 struct journal_entry_res btree_root_journal_res; 705 struct journal_entry_res replicas_journal_res; 706 struct journal_entry_res clock_journal_res; 707 struct journal_entry_res dev_usage_journal_res; 708 709 struct bch_disk_groups_cpu __rcu *disk_groups; 710 711 struct bch_opts opts; 712 713 /* Updated by bch2_sb_update():*/ 714 struct { 715 __uuid_t uuid; 716 __uuid_t user_uuid; 717 718 u16 version; 719 u16 version_min; 720 u16 version_upgrade_complete; 721 722 u8 nr_devices; 723 u8 clean; 724 725 u8 encryption_type; 726 727 u64 time_base_lo; 728 u32 time_base_hi; 729 unsigned time_units_per_sec; 730 unsigned nsec_per_time_unit; 731 u64 features; 732 u64 compat; 733 } sb; 734 735 736 struct bch_sb_handle disk_sb; 737 738 unsigned short block_bits; /* ilog2(block_size) */ 739 740 u16 btree_foreground_merge_threshold; 741 742 struct closure sb_write; 743 struct mutex sb_lock; 744 745 /* snapshot.c: */ 746 struct snapshot_table __rcu *snapshots; 747 size_t snapshot_table_size; 748 struct mutex snapshot_table_lock; 749 struct rw_semaphore snapshot_create_lock; 750 751 struct work_struct snapshot_delete_work; 752 struct work_struct snapshot_wait_for_pagecache_and_delete_work; 753 snapshot_id_list snapshots_unlinked; 754 struct mutex snapshots_unlinked_lock; 755 756 /* BTREE CACHE */ 757 struct bio_set btree_bio; 758 struct workqueue_struct *io_complete_wq; 759 760 struct btree_root btree_roots_known[BTREE_ID_NR]; 761 DARRAY(struct btree_root) btree_roots_extra; 762 struct mutex btree_root_lock; 763 764 struct btree_cache btree_cache; 765 766 /* 767 * Cache of allocated btree nodes - if we allocate a btree node and 768 * don't use it, if we free it that space can't be reused until going 769 * _all_ the way through the allocator (which exposes us to a livelock 770 * when allocating btree reserves fail halfway through) - instead, we 771 * can stick them here: 772 */ 773 struct btree_alloc btree_reserve_cache[BTREE_NODE_RESERVE * 2]; 774 unsigned btree_reserve_cache_nr; 775 struct mutex btree_reserve_cache_lock; 776 777 mempool_t btree_interior_update_pool; 778 struct list_head btree_interior_update_list; 779 struct list_head btree_interior_updates_unwritten; 780 struct mutex btree_interior_update_lock; 781 struct closure_waitlist btree_interior_update_wait; 782 783 struct workqueue_struct *btree_interior_update_worker; 784 struct work_struct btree_interior_update_work; 785 786 struct list_head pending_node_rewrites; 787 struct mutex pending_node_rewrites_lock; 788 789 /* btree_io.c: */ 790 spinlock_t btree_write_error_lock; 791 struct btree_write_stats { 792 atomic64_t nr; 793 atomic64_t bytes; 794 } btree_write_stats[BTREE_WRITE_TYPE_NR]; 795 796 /* btree_iter.c: */ 797 struct seqmutex btree_trans_lock; 798 struct list_head btree_trans_list; 799 mempool_t btree_trans_pool; 800 mempool_t btree_trans_mem_pool; 801 struct btree_trans_buf __percpu *btree_trans_bufs; 802 803 struct srcu_struct btree_trans_barrier; 804 bool btree_trans_barrier_initialized; 805 806 struct btree_key_cache btree_key_cache; 807 unsigned btree_key_cache_btrees; 808 809 struct btree_write_buffer btree_write_buffer; 810 811 struct workqueue_struct *btree_update_wq; 812 struct workqueue_struct *btree_io_complete_wq; 813 /* copygc needs its own workqueue for index updates.. */ 814 struct workqueue_struct *copygc_wq; 815 /* 816 * Use a dedicated wq for write ref holder tasks. Required to avoid 817 * dependency problems with other wq tasks that can block on ref 818 * draining, such as read-only transition. 819 */ 820 struct workqueue_struct *write_ref_wq; 821 822 /* ALLOCATION */ 823 struct bch_devs_mask rw_devs[BCH_DATA_NR]; 824 825 u64 capacity; /* sectors */ 826 827 /* 828 * When capacity _decreases_ (due to a disk being removed), we 829 * increment capacity_gen - this invalidates outstanding reservations 830 * and forces them to be revalidated 831 */ 832 u32 capacity_gen; 833 unsigned bucket_size_max; 834 835 atomic64_t sectors_available; 836 struct mutex sectors_available_lock; 837 838 struct bch_fs_pcpu __percpu *pcpu; 839 840 struct percpu_rw_semaphore mark_lock; 841 842 seqcount_t usage_lock; 843 struct bch_fs_usage *usage_base; 844 struct bch_fs_usage __percpu *usage[JOURNAL_BUF_NR]; 845 struct bch_fs_usage __percpu *usage_gc; 846 u64 __percpu *online_reserved; 847 848 /* single element mempool: */ 849 struct mutex usage_scratch_lock; 850 struct bch_fs_usage_online *usage_scratch; 851 852 struct io_clock io_clock[2]; 853 854 /* JOURNAL SEQ BLACKLIST */ 855 struct journal_seq_blacklist_table * 856 journal_seq_blacklist_table; 857 struct work_struct journal_seq_blacklist_gc_work; 858 859 /* ALLOCATOR */ 860 spinlock_t freelist_lock; 861 struct closure_waitlist freelist_wait; 862 u64 blocked_allocate; 863 u64 blocked_allocate_open_bucket; 864 865 open_bucket_idx_t open_buckets_freelist; 866 open_bucket_idx_t open_buckets_nr_free; 867 struct closure_waitlist open_buckets_wait; 868 struct open_bucket open_buckets[OPEN_BUCKETS_COUNT]; 869 open_bucket_idx_t open_buckets_hash[OPEN_BUCKETS_COUNT]; 870 871 open_bucket_idx_t open_buckets_partial[OPEN_BUCKETS_COUNT]; 872 open_bucket_idx_t open_buckets_partial_nr; 873 874 struct write_point btree_write_point; 875 struct write_point rebalance_write_point; 876 877 struct write_point write_points[WRITE_POINT_MAX]; 878 struct hlist_head write_points_hash[WRITE_POINT_HASH_NR]; 879 struct mutex write_points_hash_lock; 880 unsigned write_points_nr; 881 882 struct buckets_waiting_for_journal buckets_waiting_for_journal; 883 struct work_struct discard_work; 884 struct work_struct invalidate_work; 885 886 /* GARBAGE COLLECTION */ 887 struct task_struct *gc_thread; 888 atomic_t kick_gc; 889 unsigned long gc_count; 890 891 enum btree_id gc_gens_btree; 892 struct bpos gc_gens_pos; 893 894 /* 895 * Tracks GC's progress - everything in the range [ZERO_KEY..gc_cur_pos] 896 * has been marked by GC. 897 * 898 * gc_cur_phase is a superset of btree_ids (BTREE_ID_extents etc.) 899 * 900 * Protected by gc_pos_lock. Only written to by GC thread, so GC thread 901 * can read without a lock. 902 */ 903 seqcount_t gc_pos_lock; 904 struct gc_pos gc_pos; 905 906 /* 907 * The allocation code needs gc_mark in struct bucket to be correct, but 908 * it's not while a gc is in progress. 909 */ 910 struct rw_semaphore gc_lock; 911 struct mutex gc_gens_lock; 912 913 /* IO PATH */ 914 struct semaphore io_in_flight; 915 struct bio_set bio_read; 916 struct bio_set bio_read_split; 917 struct bio_set bio_write; 918 struct mutex bio_bounce_pages_lock; 919 mempool_t bio_bounce_pages; 920 struct bucket_nocow_lock_table 921 nocow_locks; 922 struct rhashtable promote_table; 923 924 mempool_t compression_bounce[2]; 925 mempool_t compress_workspace[BCH_COMPRESSION_TYPE_NR]; 926 mempool_t decompress_workspace; 927 ZSTD_parameters zstd_params; 928 929 struct crypto_shash *sha256; 930 struct crypto_sync_skcipher *chacha20; 931 struct crypto_shash *poly1305; 932 933 atomic64_t key_version; 934 935 mempool_t large_bkey_pool; 936 937 /* MOVE.C */ 938 struct list_head moving_context_list; 939 struct mutex moving_context_lock; 940 941 struct list_head data_progress_list; 942 struct mutex data_progress_lock; 943 944 /* REBALANCE */ 945 struct bch_fs_rebalance rebalance; 946 947 /* COPYGC */ 948 struct task_struct *copygc_thread; 949 struct write_point copygc_write_point; 950 s64 copygc_wait_at; 951 s64 copygc_wait; 952 bool copygc_running; 953 wait_queue_head_t copygc_running_wq; 954 955 /* STRIPES: */ 956 GENRADIX(struct stripe) stripes; 957 GENRADIX(struct gc_stripe) gc_stripes; 958 959 struct hlist_head ec_stripes_new[32]; 960 spinlock_t ec_stripes_new_lock; 961 962 ec_stripes_heap ec_stripes_heap; 963 struct mutex ec_stripes_heap_lock; 964 965 /* ERASURE CODING */ 966 struct list_head ec_stripe_head_list; 967 struct mutex ec_stripe_head_lock; 968 969 struct list_head ec_stripe_new_list; 970 struct mutex ec_stripe_new_lock; 971 wait_queue_head_t ec_stripe_new_wait; 972 973 struct work_struct ec_stripe_create_work; 974 u64 ec_stripe_hint; 975 976 struct work_struct ec_stripe_delete_work; 977 978 struct bio_set ec_bioset; 979 980 /* REFLINK */ 981 reflink_gc_table reflink_gc_table; 982 size_t reflink_gc_nr; 983 984 /* fs.c */ 985 struct list_head vfs_inodes_list; 986 struct mutex vfs_inodes_lock; 987 988 /* VFS IO PATH - fs-io.c */ 989 struct bio_set writepage_bioset; 990 struct bio_set dio_write_bioset; 991 struct bio_set dio_read_bioset; 992 struct bio_set nocow_flush_bioset; 993 994 /* ERRORS */ 995 struct list_head fsck_errors; 996 struct mutex fsck_error_lock; 997 bool fsck_alloc_err; 998 999 /* QUOTAS */ 1000 struct bch_memquota_type quotas[QTYP_NR]; 1001 1002 /* RECOVERY */ 1003 u64 journal_replay_seq_start; 1004 u64 journal_replay_seq_end; 1005 enum bch_recovery_pass curr_recovery_pass; 1006 /* bitmap of explicitly enabled recovery passes: */ 1007 u64 recovery_passes_explicit; 1008 u64 recovery_passes_complete; 1009 1010 /* DEBUG JUNK */ 1011 struct dentry *fs_debug_dir; 1012 struct dentry *btree_debug_dir; 1013 struct btree_debug btree_debug[BTREE_ID_NR]; 1014 struct btree *verify_data; 1015 struct btree_node *verify_ondisk; 1016 struct mutex verify_lock; 1017 1018 u64 *unused_inode_hints; 1019 unsigned inode_shard_bits; 1020 1021 /* 1022 * A btree node on disk could have too many bsets for an iterator to fit 1023 * on the stack - have to dynamically allocate them 1024 */ 1025 mempool_t fill_iter; 1026 1027 mempool_t btree_bounce_pool; 1028 1029 struct journal journal; 1030 GENRADIX(struct journal_replay *) journal_entries; 1031 u64 journal_entries_base_seq; 1032 struct journal_keys journal_keys; 1033 struct list_head journal_iters; 1034 1035 u64 last_bucket_seq_cleanup; 1036 1037 u64 counters_on_mount[BCH_COUNTER_NR]; 1038 u64 __percpu *counters; 1039 1040 unsigned btree_gc_periodic:1; 1041 unsigned copy_gc_enabled:1; 1042 bool promote_whole_extents; 1043 1044 struct bch2_time_stats times[BCH_TIME_STAT_NR]; 1045 1046 struct btree_transaction_stats btree_transaction_stats[BCH_TRANSACTIONS_NR]; 1047 }; 1048 1049 extern struct wait_queue_head bch2_read_only_wait; 1050 1051 static inline void bch2_write_ref_get(struct bch_fs *c, enum bch_write_ref ref) 1052 { 1053 #ifdef BCH_WRITE_REF_DEBUG 1054 atomic_long_inc(&c->writes[ref]); 1055 #else 1056 percpu_ref_get(&c->writes); 1057 #endif 1058 } 1059 1060 static inline bool bch2_write_ref_tryget(struct bch_fs *c, enum bch_write_ref ref) 1061 { 1062 #ifdef BCH_WRITE_REF_DEBUG 1063 return !test_bit(BCH_FS_GOING_RO, &c->flags) && 1064 atomic_long_inc_not_zero(&c->writes[ref]); 1065 #else 1066 return percpu_ref_tryget_live(&c->writes); 1067 #endif 1068 } 1069 1070 static inline void bch2_write_ref_put(struct bch_fs *c, enum bch_write_ref ref) 1071 { 1072 #ifdef BCH_WRITE_REF_DEBUG 1073 long v = atomic_long_dec_return(&c->writes[ref]); 1074 1075 BUG_ON(v < 0); 1076 if (v) 1077 return; 1078 for (unsigned i = 0; i < BCH_WRITE_REF_NR; i++) 1079 if (atomic_long_read(&c->writes[i])) 1080 return; 1081 1082 set_bit(BCH_FS_WRITE_DISABLE_COMPLETE, &c->flags); 1083 wake_up(&bch2_read_only_wait); 1084 #else 1085 percpu_ref_put(&c->writes); 1086 #endif 1087 } 1088 1089 static inline void bch2_set_ra_pages(struct bch_fs *c, unsigned ra_pages) 1090 { 1091 #ifndef NO_BCACHEFS_FS 1092 if (c->vfs_sb) 1093 c->vfs_sb->s_bdi->ra_pages = ra_pages; 1094 #endif 1095 } 1096 1097 static inline unsigned bucket_bytes(const struct bch_dev *ca) 1098 { 1099 return ca->mi.bucket_size << 9; 1100 } 1101 1102 static inline unsigned block_bytes(const struct bch_fs *c) 1103 { 1104 return c->opts.block_size; 1105 } 1106 1107 static inline unsigned block_sectors(const struct bch_fs *c) 1108 { 1109 return c->opts.block_size >> 9; 1110 } 1111 1112 static inline size_t btree_sectors(const struct bch_fs *c) 1113 { 1114 return c->opts.btree_node_size >> 9; 1115 } 1116 1117 static inline bool btree_id_cached(const struct bch_fs *c, enum btree_id btree) 1118 { 1119 return c->btree_key_cache_btrees & (1U << btree); 1120 } 1121 1122 static inline struct timespec64 bch2_time_to_timespec(const struct bch_fs *c, s64 time) 1123 { 1124 struct timespec64 t; 1125 s32 rem; 1126 1127 time += c->sb.time_base_lo; 1128 1129 t.tv_sec = div_s64_rem(time, c->sb.time_units_per_sec, &rem); 1130 t.tv_nsec = rem * c->sb.nsec_per_time_unit; 1131 return t; 1132 } 1133 1134 static inline s64 timespec_to_bch2_time(const struct bch_fs *c, struct timespec64 ts) 1135 { 1136 return (ts.tv_sec * c->sb.time_units_per_sec + 1137 (int) ts.tv_nsec / c->sb.nsec_per_time_unit) - c->sb.time_base_lo; 1138 } 1139 1140 static inline s64 bch2_current_time(const struct bch_fs *c) 1141 { 1142 struct timespec64 now; 1143 1144 ktime_get_coarse_real_ts64(&now); 1145 return timespec_to_bch2_time(c, now); 1146 } 1147 1148 static inline bool bch2_dev_exists2(const struct bch_fs *c, unsigned dev) 1149 { 1150 return dev < c->sb.nr_devices && c->devs[dev]; 1151 } 1152 1153 #define BKEY_PADDED_ONSTACK(key, pad) \ 1154 struct { struct bkey_i key; __u64 key ## _pad[pad]; } 1155 1156 #endif /* _BCACHEFS_H */ 1157