1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _BCACHEFS_FORMAT_H 3 #define _BCACHEFS_FORMAT_H 4 5 /* 6 * bcachefs on disk data structures 7 * 8 * OVERVIEW: 9 * 10 * There are three main types of on disk data structures in bcachefs (this is 11 * reduced from 5 in bcache) 12 * 13 * - superblock 14 * - journal 15 * - btree 16 * 17 * The btree is the primary structure; most metadata exists as keys in the 18 * various btrees. There are only a small number of btrees, they're not 19 * sharded - we have one btree for extents, another for inodes, et cetera. 20 * 21 * SUPERBLOCK: 22 * 23 * The superblock contains the location of the journal, the list of devices in 24 * the filesystem, and in general any metadata we need in order to decide 25 * whether we can start a filesystem or prior to reading the journal/btree 26 * roots. 27 * 28 * The superblock is extensible, and most of the contents of the superblock are 29 * in variable length, type tagged fields; see struct bch_sb_field. 30 * 31 * Backup superblocks do not reside in a fixed location; also, superblocks do 32 * not have a fixed size. To locate backup superblocks we have struct 33 * bch_sb_layout; we store a copy of this inside every superblock, and also 34 * before the first superblock. 35 * 36 * JOURNAL: 37 * 38 * The journal primarily records btree updates in the order they occurred; 39 * journal replay consists of just iterating over all the keys in the open 40 * journal entries and re-inserting them into the btrees. 41 * 42 * The journal also contains entry types for the btree roots, and blacklisted 43 * journal sequence numbers (see journal_seq_blacklist.c). 44 * 45 * BTREE: 46 * 47 * bcachefs btrees are copy on write b+ trees, where nodes are big (typically 48 * 128k-256k) and log structured. We use struct btree_node for writing the first 49 * entry in a given node (offset 0), and struct btree_node_entry for all 50 * subsequent writes. 51 * 52 * After the header, btree node entries contain a list of keys in sorted order. 53 * Values are stored inline with the keys; since values are variable length (and 54 * keys effectively are variable length too, due to packing) we can't do random 55 * access without building up additional in memory tables in the btree node read 56 * path. 57 * 58 * BTREE KEYS (struct bkey): 59 * 60 * The various btrees share a common format for the key - so as to avoid 61 * switching in fastpath lookup/comparison code - but define their own 62 * structures for the key values. 63 * 64 * The size of a key/value pair is stored as a u8 in units of u64s, so the max 65 * size is just under 2k. The common part also contains a type tag for the 66 * value, and a format field indicating whether the key is packed or not (and 67 * also meant to allow adding new key fields in the future, if desired). 68 * 69 * bkeys, when stored within a btree node, may also be packed. In that case, the 70 * bkey_format in that node is used to unpack it. Packed bkeys mean that we can 71 * be generous with field sizes in the common part of the key format (64 bit 72 * inode number, 64 bit offset, 96 bit version field, etc.) for negligible cost. 73 */ 74 75 #include <asm/types.h> 76 #include <asm/byteorder.h> 77 #include <linux/kernel.h> 78 #include <linux/uuid.h> 79 #include "vstructs.h" 80 81 #ifdef __KERNEL__ 82 typedef uuid_t __uuid_t; 83 #endif 84 85 #define BITMASK(name, type, field, offset, end) \ 86 static const __maybe_unused unsigned name##_OFFSET = offset; \ 87 static const __maybe_unused unsigned name##_BITS = (end - offset); \ 88 \ 89 static inline __u64 name(const type *k) \ 90 { \ 91 return (k->field >> offset) & ~(~0ULL << (end - offset)); \ 92 } \ 93 \ 94 static inline void SET_##name(type *k, __u64 v) \ 95 { \ 96 k->field &= ~(~(~0ULL << (end - offset)) << offset); \ 97 k->field |= (v & ~(~0ULL << (end - offset))) << offset; \ 98 } 99 100 #define LE_BITMASK(_bits, name, type, field, offset, end) \ 101 static const __maybe_unused unsigned name##_OFFSET = offset; \ 102 static const __maybe_unused unsigned name##_BITS = (end - offset); \ 103 static const __maybe_unused __u##_bits name##_MAX = (1ULL << (end - offset)) - 1;\ 104 \ 105 static inline __u64 name(const type *k) \ 106 { \ 107 return (__le##_bits##_to_cpu(k->field) >> offset) & \ 108 ~(~0ULL << (end - offset)); \ 109 } \ 110 \ 111 static inline void SET_##name(type *k, __u64 v) \ 112 { \ 113 __u##_bits new = __le##_bits##_to_cpu(k->field); \ 114 \ 115 new &= ~(~(~0ULL << (end - offset)) << offset); \ 116 new |= (v & ~(~0ULL << (end - offset))) << offset; \ 117 k->field = __cpu_to_le##_bits(new); \ 118 } 119 120 #define LE16_BITMASK(n, t, f, o, e) LE_BITMASK(16, n, t, f, o, e) 121 #define LE32_BITMASK(n, t, f, o, e) LE_BITMASK(32, n, t, f, o, e) 122 #define LE64_BITMASK(n, t, f, o, e) LE_BITMASK(64, n, t, f, o, e) 123 124 struct bkey_format { 125 __u8 key_u64s; 126 __u8 nr_fields; 127 /* One unused slot for now: */ 128 __u8 bits_per_field[6]; 129 __le64 field_offset[6]; 130 }; 131 132 /* Btree keys - all units are in sectors */ 133 134 struct bpos { 135 /* 136 * Word order matches machine byte order - btree code treats a bpos as a 137 * single large integer, for search/comparison purposes 138 * 139 * Note that wherever a bpos is embedded in another on disk data 140 * structure, it has to be byte swabbed when reading in metadata that 141 * wasn't written in native endian order: 142 */ 143 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ 144 __u32 snapshot; 145 __u64 offset; 146 __u64 inode; 147 #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ 148 __u64 inode; 149 __u64 offset; /* Points to end of extent - sectors */ 150 __u32 snapshot; 151 #else 152 #error edit for your odd byteorder. 153 #endif 154 } __packed __aligned(4); 155 156 #define KEY_INODE_MAX ((__u64)~0ULL) 157 #define KEY_OFFSET_MAX ((__u64)~0ULL) 158 #define KEY_SNAPSHOT_MAX ((__u32)~0U) 159 #define KEY_SIZE_MAX ((__u32)~0U) 160 161 static inline struct bpos SPOS(__u64 inode, __u64 offset, __u32 snapshot) 162 { 163 return (struct bpos) { 164 .inode = inode, 165 .offset = offset, 166 .snapshot = snapshot, 167 }; 168 } 169 170 #define POS_MIN SPOS(0, 0, 0) 171 #define POS_MAX SPOS(KEY_INODE_MAX, KEY_OFFSET_MAX, 0) 172 #define SPOS_MAX SPOS(KEY_INODE_MAX, KEY_OFFSET_MAX, KEY_SNAPSHOT_MAX) 173 #define POS(_inode, _offset) SPOS(_inode, _offset, 0) 174 175 /* Empty placeholder struct, for container_of() */ 176 struct bch_val { 177 __u64 __nothing[0]; 178 }; 179 180 struct bversion { 181 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ 182 __u64 lo; 183 __u32 hi; 184 #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ 185 __u32 hi; 186 __u64 lo; 187 #endif 188 } __packed __aligned(4); 189 190 struct bkey { 191 /* Size of combined key and value, in u64s */ 192 __u8 u64s; 193 194 /* Format of key (0 for format local to btree node) */ 195 #if defined(__LITTLE_ENDIAN_BITFIELD) 196 __u8 format:7, 197 needs_whiteout:1; 198 #elif defined (__BIG_ENDIAN_BITFIELD) 199 __u8 needs_whiteout:1, 200 format:7; 201 #else 202 #error edit for your odd byteorder. 203 #endif 204 205 /* Type of the value */ 206 __u8 type; 207 208 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ 209 __u8 pad[1]; 210 211 struct bversion version; 212 __u32 size; /* extent size, in sectors */ 213 struct bpos p; 214 #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ 215 struct bpos p; 216 __u32 size; /* extent size, in sectors */ 217 struct bversion version; 218 219 __u8 pad[1]; 220 #endif 221 } __packed __aligned(8); 222 223 struct bkey_packed { 224 __u64 _data[0]; 225 226 /* Size of combined key and value, in u64s */ 227 __u8 u64s; 228 229 /* Format of key (0 for format local to btree node) */ 230 231 /* 232 * XXX: next incompat on disk format change, switch format and 233 * needs_whiteout - bkey_packed() will be cheaper if format is the high 234 * bits of the bitfield 235 */ 236 #if defined(__LITTLE_ENDIAN_BITFIELD) 237 __u8 format:7, 238 needs_whiteout:1; 239 #elif defined (__BIG_ENDIAN_BITFIELD) 240 __u8 needs_whiteout:1, 241 format:7; 242 #endif 243 244 /* Type of the value */ 245 __u8 type; 246 __u8 key_start[0]; 247 248 /* 249 * We copy bkeys with struct assignment in various places, and while 250 * that shouldn't be done with packed bkeys we can't disallow it in C, 251 * and it's legal to cast a bkey to a bkey_packed - so padding it out 252 * to the same size as struct bkey should hopefully be safest. 253 */ 254 __u8 pad[sizeof(struct bkey) - 3]; 255 } __packed __aligned(8); 256 257 typedef struct { 258 __le64 lo; 259 __le64 hi; 260 } bch_le128; 261 262 #define BKEY_U64s (sizeof(struct bkey) / sizeof(__u64)) 263 #define BKEY_U64s_MAX U8_MAX 264 #define BKEY_VAL_U64s_MAX (BKEY_U64s_MAX - BKEY_U64s) 265 266 #define KEY_PACKED_BITS_START 24 267 268 #define KEY_FORMAT_LOCAL_BTREE 0 269 #define KEY_FORMAT_CURRENT 1 270 271 enum bch_bkey_fields { 272 BKEY_FIELD_INODE, 273 BKEY_FIELD_OFFSET, 274 BKEY_FIELD_SNAPSHOT, 275 BKEY_FIELD_SIZE, 276 BKEY_FIELD_VERSION_HI, 277 BKEY_FIELD_VERSION_LO, 278 BKEY_NR_FIELDS, 279 }; 280 281 #define bkey_format_field(name, field) \ 282 [BKEY_FIELD_##name] = (sizeof(((struct bkey *) NULL)->field) * 8) 283 284 #define BKEY_FORMAT_CURRENT \ 285 ((struct bkey_format) { \ 286 .key_u64s = BKEY_U64s, \ 287 .nr_fields = BKEY_NR_FIELDS, \ 288 .bits_per_field = { \ 289 bkey_format_field(INODE, p.inode), \ 290 bkey_format_field(OFFSET, p.offset), \ 291 bkey_format_field(SNAPSHOT, p.snapshot), \ 292 bkey_format_field(SIZE, size), \ 293 bkey_format_field(VERSION_HI, version.hi), \ 294 bkey_format_field(VERSION_LO, version.lo), \ 295 }, \ 296 }) 297 298 /* bkey with inline value */ 299 struct bkey_i { 300 __u64 _data[0]; 301 302 struct bkey k; 303 struct bch_val v; 304 }; 305 306 #define KEY(_inode, _offset, _size) \ 307 ((struct bkey) { \ 308 .u64s = BKEY_U64s, \ 309 .format = KEY_FORMAT_CURRENT, \ 310 .p = POS(_inode, _offset), \ 311 .size = _size, \ 312 }) 313 314 static inline void bkey_init(struct bkey *k) 315 { 316 *k = KEY(0, 0, 0); 317 } 318 319 #define bkey_bytes(_k) ((_k)->u64s * sizeof(__u64)) 320 321 #define __BKEY_PADDED(key, pad) \ 322 struct bkey_i key; __u64 key ## _pad[pad] 323 324 /* 325 * - DELETED keys are used internally to mark keys that should be ignored but 326 * override keys in composition order. Their version number is ignored. 327 * 328 * - DISCARDED keys indicate that the data is all 0s because it has been 329 * discarded. DISCARDs may have a version; if the version is nonzero the key 330 * will be persistent, otherwise the key will be dropped whenever the btree 331 * node is rewritten (like DELETED keys). 332 * 333 * - ERROR: any read of the data returns a read error, as the data was lost due 334 * to a failing device. Like DISCARDED keys, they can be removed (overridden) 335 * by new writes or cluster-wide GC. Node repair can also overwrite them with 336 * the same or a more recent version number, but not with an older version 337 * number. 338 * 339 * - WHITEOUT: for hash table btrees 340 */ 341 #define BCH_BKEY_TYPES() \ 342 x(deleted, 0) \ 343 x(whiteout, 1) \ 344 x(error, 2) \ 345 x(cookie, 3) \ 346 x(hash_whiteout, 4) \ 347 x(btree_ptr, 5) \ 348 x(extent, 6) \ 349 x(reservation, 7) \ 350 x(inode, 8) \ 351 x(inode_generation, 9) \ 352 x(dirent, 10) \ 353 x(xattr, 11) \ 354 x(alloc, 12) \ 355 x(quota, 13) \ 356 x(stripe, 14) \ 357 x(reflink_p, 15) \ 358 x(reflink_v, 16) \ 359 x(inline_data, 17) \ 360 x(btree_ptr_v2, 18) \ 361 x(indirect_inline_data, 19) \ 362 x(alloc_v2, 20) \ 363 x(subvolume, 21) \ 364 x(snapshot, 22) \ 365 x(inode_v2, 23) \ 366 x(alloc_v3, 24) \ 367 x(set, 25) \ 368 x(lru, 26) \ 369 x(alloc_v4, 27) \ 370 x(backpointer, 28) \ 371 x(inode_v3, 29) \ 372 x(bucket_gens, 30) \ 373 x(snapshot_tree, 31) \ 374 x(logged_op_truncate, 32) \ 375 x(logged_op_finsert, 33) 376 377 enum bch_bkey_type { 378 #define x(name, nr) KEY_TYPE_##name = nr, 379 BCH_BKEY_TYPES() 380 #undef x 381 KEY_TYPE_MAX, 382 }; 383 384 struct bch_deleted { 385 struct bch_val v; 386 }; 387 388 struct bch_whiteout { 389 struct bch_val v; 390 }; 391 392 struct bch_error { 393 struct bch_val v; 394 }; 395 396 struct bch_cookie { 397 struct bch_val v; 398 __le64 cookie; 399 }; 400 401 struct bch_hash_whiteout { 402 struct bch_val v; 403 }; 404 405 struct bch_set { 406 struct bch_val v; 407 }; 408 409 /* Extents */ 410 411 /* 412 * In extent bkeys, the value is a list of pointers (bch_extent_ptr), optionally 413 * preceded by checksum/compression information (bch_extent_crc32 or 414 * bch_extent_crc64). 415 * 416 * One major determining factor in the format of extents is how we handle and 417 * represent extents that have been partially overwritten and thus trimmed: 418 * 419 * If an extent is not checksummed or compressed, when the extent is trimmed we 420 * don't have to remember the extent we originally allocated and wrote: we can 421 * merely adjust ptr->offset to point to the start of the data that is currently 422 * live. The size field in struct bkey records the current (live) size of the 423 * extent, and is also used to mean "size of region on disk that we point to" in 424 * this case. 425 * 426 * Thus an extent that is not checksummed or compressed will consist only of a 427 * list of bch_extent_ptrs, with none of the fields in 428 * bch_extent_crc32/bch_extent_crc64. 429 * 430 * When an extent is checksummed or compressed, it's not possible to read only 431 * the data that is currently live: we have to read the entire extent that was 432 * originally written, and then return only the part of the extent that is 433 * currently live. 434 * 435 * Thus, in addition to the current size of the extent in struct bkey, we need 436 * to store the size of the originally allocated space - this is the 437 * compressed_size and uncompressed_size fields in bch_extent_crc32/64. Also, 438 * when the extent is trimmed, instead of modifying the offset field of the 439 * pointer, we keep a second smaller offset field - "offset into the original 440 * extent of the currently live region". 441 * 442 * The other major determining factor is replication and data migration: 443 * 444 * Each pointer may have its own bch_extent_crc32/64. When doing a replicated 445 * write, we will initially write all the replicas in the same format, with the 446 * same checksum type and compression format - however, when copygc runs later (or 447 * tiering/cache promotion, anything that moves data), it is not in general 448 * going to rewrite all the pointers at once - one of the replicas may be in a 449 * bucket on one device that has very little fragmentation while another lives 450 * in a bucket that has become heavily fragmented, and thus is being rewritten 451 * sooner than the rest. 452 * 453 * Thus it will only move a subset of the pointers (or in the case of 454 * tiering/cache promotion perhaps add a single pointer without dropping any 455 * current pointers), and if the extent has been partially overwritten it must 456 * write only the currently live portion (or copygc would not be able to reduce 457 * fragmentation!) - which necessitates a different bch_extent_crc format for 458 * the new pointer. 459 * 460 * But in the interests of space efficiency, we don't want to store one 461 * bch_extent_crc for each pointer if we don't have to. 462 * 463 * Thus, a bch_extent consists of bch_extent_crc32s, bch_extent_crc64s, and 464 * bch_extent_ptrs appended arbitrarily one after the other. We determine the 465 * type of a given entry with a scheme similar to utf8 (except we're encoding a 466 * type, not a size), encoding the type in the position of the first set bit: 467 * 468 * bch_extent_crc32 - 0b1 469 * bch_extent_ptr - 0b10 470 * bch_extent_crc64 - 0b100 471 * 472 * We do it this way because bch_extent_crc32 is _very_ constrained on bits (and 473 * bch_extent_crc64 is the least constrained). 474 * 475 * Then, each bch_extent_crc32/64 applies to the pointers that follow after it, 476 * until the next bch_extent_crc32/64. 477 * 478 * If there are no bch_extent_crcs preceding a bch_extent_ptr, then that pointer 479 * is neither checksummed nor compressed. 480 */ 481 482 /* 128 bits, sufficient for cryptographic MACs: */ 483 struct bch_csum { 484 __le64 lo; 485 __le64 hi; 486 } __packed __aligned(8); 487 488 #define BCH_EXTENT_ENTRY_TYPES() \ 489 x(ptr, 0) \ 490 x(crc32, 1) \ 491 x(crc64, 2) \ 492 x(crc128, 3) \ 493 x(stripe_ptr, 4) \ 494 x(rebalance, 5) 495 #define BCH_EXTENT_ENTRY_MAX 6 496 497 enum bch_extent_entry_type { 498 #define x(f, n) BCH_EXTENT_ENTRY_##f = n, 499 BCH_EXTENT_ENTRY_TYPES() 500 #undef x 501 }; 502 503 /* Compressed/uncompressed size are stored biased by 1: */ 504 struct bch_extent_crc32 { 505 #if defined(__LITTLE_ENDIAN_BITFIELD) 506 __u32 type:2, 507 _compressed_size:7, 508 _uncompressed_size:7, 509 offset:7, 510 _unused:1, 511 csum_type:4, 512 compression_type:4; 513 __u32 csum; 514 #elif defined (__BIG_ENDIAN_BITFIELD) 515 __u32 csum; 516 __u32 compression_type:4, 517 csum_type:4, 518 _unused:1, 519 offset:7, 520 _uncompressed_size:7, 521 _compressed_size:7, 522 type:2; 523 #endif 524 } __packed __aligned(8); 525 526 #define CRC32_SIZE_MAX (1U << 7) 527 #define CRC32_NONCE_MAX 0 528 529 struct bch_extent_crc64 { 530 #if defined(__LITTLE_ENDIAN_BITFIELD) 531 __u64 type:3, 532 _compressed_size:9, 533 _uncompressed_size:9, 534 offset:9, 535 nonce:10, 536 csum_type:4, 537 compression_type:4, 538 csum_hi:16; 539 #elif defined (__BIG_ENDIAN_BITFIELD) 540 __u64 csum_hi:16, 541 compression_type:4, 542 csum_type:4, 543 nonce:10, 544 offset:9, 545 _uncompressed_size:9, 546 _compressed_size:9, 547 type:3; 548 #endif 549 __u64 csum_lo; 550 } __packed __aligned(8); 551 552 #define CRC64_SIZE_MAX (1U << 9) 553 #define CRC64_NONCE_MAX ((1U << 10) - 1) 554 555 struct bch_extent_crc128 { 556 #if defined(__LITTLE_ENDIAN_BITFIELD) 557 __u64 type:4, 558 _compressed_size:13, 559 _uncompressed_size:13, 560 offset:13, 561 nonce:13, 562 csum_type:4, 563 compression_type:4; 564 #elif defined (__BIG_ENDIAN_BITFIELD) 565 __u64 compression_type:4, 566 csum_type:4, 567 nonce:13, 568 offset:13, 569 _uncompressed_size:13, 570 _compressed_size:13, 571 type:4; 572 #endif 573 struct bch_csum csum; 574 } __packed __aligned(8); 575 576 #define CRC128_SIZE_MAX (1U << 13) 577 #define CRC128_NONCE_MAX ((1U << 13) - 1) 578 579 /* 580 * @reservation - pointer hasn't been written to, just reserved 581 */ 582 struct bch_extent_ptr { 583 #if defined(__LITTLE_ENDIAN_BITFIELD) 584 __u64 type:1, 585 cached:1, 586 unused:1, 587 unwritten:1, 588 offset:44, /* 8 petabytes */ 589 dev:8, 590 gen:8; 591 #elif defined (__BIG_ENDIAN_BITFIELD) 592 __u64 gen:8, 593 dev:8, 594 offset:44, 595 unwritten:1, 596 unused:1, 597 cached:1, 598 type:1; 599 #endif 600 } __packed __aligned(8); 601 602 struct bch_extent_stripe_ptr { 603 #if defined(__LITTLE_ENDIAN_BITFIELD) 604 __u64 type:5, 605 block:8, 606 redundancy:4, 607 idx:47; 608 #elif defined (__BIG_ENDIAN_BITFIELD) 609 __u64 idx:47, 610 redundancy:4, 611 block:8, 612 type:5; 613 #endif 614 }; 615 616 struct bch_extent_reservation { 617 #if defined(__LITTLE_ENDIAN_BITFIELD) 618 __u64 type:6, 619 unused:22, 620 replicas:4, 621 generation:32; 622 #elif defined (__BIG_ENDIAN_BITFIELD) 623 __u64 generation:32, 624 replicas:4, 625 unused:22, 626 type:6; 627 #endif 628 }; 629 630 struct bch_extent_rebalance { 631 #if defined(__LITTLE_ENDIAN_BITFIELD) 632 __u64 type:7, 633 unused:33, 634 compression:8, 635 target:16; 636 #elif defined (__BIG_ENDIAN_BITFIELD) 637 __u64 target:16, 638 compression:8, 639 unused:33, 640 type:7; 641 #endif 642 }; 643 644 union bch_extent_entry { 645 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ || __BITS_PER_LONG == 64 646 unsigned long type; 647 #elif __BITS_PER_LONG == 32 648 struct { 649 unsigned long pad; 650 unsigned long type; 651 }; 652 #else 653 #error edit for your odd byteorder. 654 #endif 655 656 #define x(f, n) struct bch_extent_##f f; 657 BCH_EXTENT_ENTRY_TYPES() 658 #undef x 659 }; 660 661 struct bch_btree_ptr { 662 struct bch_val v; 663 664 __u64 _data[0]; 665 struct bch_extent_ptr start[]; 666 } __packed __aligned(8); 667 668 struct bch_btree_ptr_v2 { 669 struct bch_val v; 670 671 __u64 mem_ptr; 672 __le64 seq; 673 __le16 sectors_written; 674 __le16 flags; 675 struct bpos min_key; 676 __u64 _data[0]; 677 struct bch_extent_ptr start[]; 678 } __packed __aligned(8); 679 680 LE16_BITMASK(BTREE_PTR_RANGE_UPDATED, struct bch_btree_ptr_v2, flags, 0, 1); 681 682 struct bch_extent { 683 struct bch_val v; 684 685 __u64 _data[0]; 686 union bch_extent_entry start[]; 687 } __packed __aligned(8); 688 689 struct bch_reservation { 690 struct bch_val v; 691 692 __le32 generation; 693 __u8 nr_replicas; 694 __u8 pad[3]; 695 } __packed __aligned(8); 696 697 /* Maximum size (in u64s) a single pointer could be: */ 698 #define BKEY_EXTENT_PTR_U64s_MAX\ 699 ((sizeof(struct bch_extent_crc128) + \ 700 sizeof(struct bch_extent_ptr)) / sizeof(__u64)) 701 702 /* Maximum possible size of an entire extent value: */ 703 #define BKEY_EXTENT_VAL_U64s_MAX \ 704 (1 + BKEY_EXTENT_PTR_U64s_MAX * (BCH_REPLICAS_MAX + 1)) 705 706 /* * Maximum possible size of an entire extent, key + value: */ 707 #define BKEY_EXTENT_U64s_MAX (BKEY_U64s + BKEY_EXTENT_VAL_U64s_MAX) 708 709 /* Btree pointers don't carry around checksums: */ 710 #define BKEY_BTREE_PTR_VAL_U64s_MAX \ 711 ((sizeof(struct bch_btree_ptr_v2) + \ 712 sizeof(struct bch_extent_ptr) * BCH_REPLICAS_MAX) / sizeof(__u64)) 713 #define BKEY_BTREE_PTR_U64s_MAX \ 714 (BKEY_U64s + BKEY_BTREE_PTR_VAL_U64s_MAX) 715 716 /* Inodes */ 717 718 #define BLOCKDEV_INODE_MAX 4096 719 720 #define BCACHEFS_ROOT_INO 4096 721 722 struct bch_inode { 723 struct bch_val v; 724 725 __le64 bi_hash_seed; 726 __le32 bi_flags; 727 __le16 bi_mode; 728 __u8 fields[]; 729 } __packed __aligned(8); 730 731 struct bch_inode_v2 { 732 struct bch_val v; 733 734 __le64 bi_journal_seq; 735 __le64 bi_hash_seed; 736 __le64 bi_flags; 737 __le16 bi_mode; 738 __u8 fields[]; 739 } __packed __aligned(8); 740 741 struct bch_inode_v3 { 742 struct bch_val v; 743 744 __le64 bi_journal_seq; 745 __le64 bi_hash_seed; 746 __le64 bi_flags; 747 __le64 bi_sectors; 748 __le64 bi_size; 749 __le64 bi_version; 750 __u8 fields[]; 751 } __packed __aligned(8); 752 753 #define INODEv3_FIELDS_START_INITIAL 6 754 #define INODEv3_FIELDS_START_CUR (offsetof(struct bch_inode_v3, fields) / sizeof(__u64)) 755 756 struct bch_inode_generation { 757 struct bch_val v; 758 759 __le32 bi_generation; 760 __le32 pad; 761 } __packed __aligned(8); 762 763 /* 764 * bi_subvol and bi_parent_subvol are only set for subvolume roots: 765 */ 766 767 #define BCH_INODE_FIELDS_v2() \ 768 x(bi_atime, 96) \ 769 x(bi_ctime, 96) \ 770 x(bi_mtime, 96) \ 771 x(bi_otime, 96) \ 772 x(bi_size, 64) \ 773 x(bi_sectors, 64) \ 774 x(bi_uid, 32) \ 775 x(bi_gid, 32) \ 776 x(bi_nlink, 32) \ 777 x(bi_generation, 32) \ 778 x(bi_dev, 32) \ 779 x(bi_data_checksum, 8) \ 780 x(bi_compression, 8) \ 781 x(bi_project, 32) \ 782 x(bi_background_compression, 8) \ 783 x(bi_data_replicas, 8) \ 784 x(bi_promote_target, 16) \ 785 x(bi_foreground_target, 16) \ 786 x(bi_background_target, 16) \ 787 x(bi_erasure_code, 16) \ 788 x(bi_fields_set, 16) \ 789 x(bi_dir, 64) \ 790 x(bi_dir_offset, 64) \ 791 x(bi_subvol, 32) \ 792 x(bi_parent_subvol, 32) 793 794 #define BCH_INODE_FIELDS_v3() \ 795 x(bi_atime, 96) \ 796 x(bi_ctime, 96) \ 797 x(bi_mtime, 96) \ 798 x(bi_otime, 96) \ 799 x(bi_uid, 32) \ 800 x(bi_gid, 32) \ 801 x(bi_nlink, 32) \ 802 x(bi_generation, 32) \ 803 x(bi_dev, 32) \ 804 x(bi_data_checksum, 8) \ 805 x(bi_compression, 8) \ 806 x(bi_project, 32) \ 807 x(bi_background_compression, 8) \ 808 x(bi_data_replicas, 8) \ 809 x(bi_promote_target, 16) \ 810 x(bi_foreground_target, 16) \ 811 x(bi_background_target, 16) \ 812 x(bi_erasure_code, 16) \ 813 x(bi_fields_set, 16) \ 814 x(bi_dir, 64) \ 815 x(bi_dir_offset, 64) \ 816 x(bi_subvol, 32) \ 817 x(bi_parent_subvol, 32) \ 818 x(bi_nocow, 8) 819 820 /* subset of BCH_INODE_FIELDS */ 821 #define BCH_INODE_OPTS() \ 822 x(data_checksum, 8) \ 823 x(compression, 8) \ 824 x(project, 32) \ 825 x(background_compression, 8) \ 826 x(data_replicas, 8) \ 827 x(promote_target, 16) \ 828 x(foreground_target, 16) \ 829 x(background_target, 16) \ 830 x(erasure_code, 16) \ 831 x(nocow, 8) 832 833 enum inode_opt_id { 834 #define x(name, ...) \ 835 Inode_opt_##name, 836 BCH_INODE_OPTS() 837 #undef x 838 Inode_opt_nr, 839 }; 840 841 enum { 842 /* 843 * User flags (get/settable with FS_IOC_*FLAGS, correspond to FS_*_FL 844 * flags) 845 */ 846 __BCH_INODE_SYNC = 0, 847 __BCH_INODE_IMMUTABLE = 1, 848 __BCH_INODE_APPEND = 2, 849 __BCH_INODE_NODUMP = 3, 850 __BCH_INODE_NOATIME = 4, 851 852 __BCH_INODE_I_SIZE_DIRTY = 5, /* obsolete */ 853 __BCH_INODE_I_SECTORS_DIRTY = 6, /* obsolete */ 854 __BCH_INODE_UNLINKED = 7, 855 __BCH_INODE_BACKPTR_UNTRUSTED = 8, 856 857 /* bits 20+ reserved for packed fields below: */ 858 }; 859 860 #define BCH_INODE_SYNC (1 << __BCH_INODE_SYNC) 861 #define BCH_INODE_IMMUTABLE (1 << __BCH_INODE_IMMUTABLE) 862 #define BCH_INODE_APPEND (1 << __BCH_INODE_APPEND) 863 #define BCH_INODE_NODUMP (1 << __BCH_INODE_NODUMP) 864 #define BCH_INODE_NOATIME (1 << __BCH_INODE_NOATIME) 865 #define BCH_INODE_I_SIZE_DIRTY (1 << __BCH_INODE_I_SIZE_DIRTY) 866 #define BCH_INODE_I_SECTORS_DIRTY (1 << __BCH_INODE_I_SECTORS_DIRTY) 867 #define BCH_INODE_UNLINKED (1 << __BCH_INODE_UNLINKED) 868 #define BCH_INODE_BACKPTR_UNTRUSTED (1 << __BCH_INODE_BACKPTR_UNTRUSTED) 869 870 LE32_BITMASK(INODE_STR_HASH, struct bch_inode, bi_flags, 20, 24); 871 LE32_BITMASK(INODE_NR_FIELDS, struct bch_inode, bi_flags, 24, 31); 872 LE32_BITMASK(INODE_NEW_VARINT, struct bch_inode, bi_flags, 31, 32); 873 874 LE64_BITMASK(INODEv2_STR_HASH, struct bch_inode_v2, bi_flags, 20, 24); 875 LE64_BITMASK(INODEv2_NR_FIELDS, struct bch_inode_v2, bi_flags, 24, 31); 876 877 LE64_BITMASK(INODEv3_STR_HASH, struct bch_inode_v3, bi_flags, 20, 24); 878 LE64_BITMASK(INODEv3_NR_FIELDS, struct bch_inode_v3, bi_flags, 24, 31); 879 880 LE64_BITMASK(INODEv3_FIELDS_START, 881 struct bch_inode_v3, bi_flags, 31, 36); 882 LE64_BITMASK(INODEv3_MODE, struct bch_inode_v3, bi_flags, 36, 52); 883 884 /* Dirents */ 885 886 /* 887 * Dirents (and xattrs) have to implement string lookups; since our b-tree 888 * doesn't support arbitrary length strings for the key, we instead index by a 889 * 64 bit hash (currently truncated sha1) of the string, stored in the offset 890 * field of the key - using linear probing to resolve hash collisions. This also 891 * provides us with the readdir cookie posix requires. 892 * 893 * Linear probing requires us to use whiteouts for deletions, in the event of a 894 * collision: 895 */ 896 897 struct bch_dirent { 898 struct bch_val v; 899 900 /* Target inode number: */ 901 union { 902 __le64 d_inum; 903 struct { /* DT_SUBVOL */ 904 __le32 d_child_subvol; 905 __le32 d_parent_subvol; 906 }; 907 }; 908 909 /* 910 * Copy of mode bits 12-15 from the target inode - so userspace can get 911 * the filetype without having to do a stat() 912 */ 913 __u8 d_type; 914 915 __u8 d_name[]; 916 } __packed __aligned(8); 917 918 #define DT_SUBVOL 16 919 #define BCH_DT_MAX 17 920 921 #define BCH_NAME_MAX 512 922 923 /* Xattrs */ 924 925 #define KEY_TYPE_XATTR_INDEX_USER 0 926 #define KEY_TYPE_XATTR_INDEX_POSIX_ACL_ACCESS 1 927 #define KEY_TYPE_XATTR_INDEX_POSIX_ACL_DEFAULT 2 928 #define KEY_TYPE_XATTR_INDEX_TRUSTED 3 929 #define KEY_TYPE_XATTR_INDEX_SECURITY 4 930 931 struct bch_xattr { 932 struct bch_val v; 933 __u8 x_type; 934 __u8 x_name_len; 935 __le16 x_val_len; 936 __u8 x_name[]; 937 } __packed __aligned(8); 938 939 /* Bucket/allocation information: */ 940 941 struct bch_alloc { 942 struct bch_val v; 943 __u8 fields; 944 __u8 gen; 945 __u8 data[]; 946 } __packed __aligned(8); 947 948 #define BCH_ALLOC_FIELDS_V1() \ 949 x(read_time, 16) \ 950 x(write_time, 16) \ 951 x(data_type, 8) \ 952 x(dirty_sectors, 16) \ 953 x(cached_sectors, 16) \ 954 x(oldest_gen, 8) \ 955 x(stripe, 32) \ 956 x(stripe_redundancy, 8) 957 958 enum { 959 #define x(name, _bits) BCH_ALLOC_FIELD_V1_##name, 960 BCH_ALLOC_FIELDS_V1() 961 #undef x 962 }; 963 964 struct bch_alloc_v2 { 965 struct bch_val v; 966 __u8 nr_fields; 967 __u8 gen; 968 __u8 oldest_gen; 969 __u8 data_type; 970 __u8 data[]; 971 } __packed __aligned(8); 972 973 #define BCH_ALLOC_FIELDS_V2() \ 974 x(read_time, 64) \ 975 x(write_time, 64) \ 976 x(dirty_sectors, 32) \ 977 x(cached_sectors, 32) \ 978 x(stripe, 32) \ 979 x(stripe_redundancy, 8) 980 981 struct bch_alloc_v3 { 982 struct bch_val v; 983 __le64 journal_seq; 984 __le32 flags; 985 __u8 nr_fields; 986 __u8 gen; 987 __u8 oldest_gen; 988 __u8 data_type; 989 __u8 data[]; 990 } __packed __aligned(8); 991 992 LE32_BITMASK(BCH_ALLOC_V3_NEED_DISCARD,struct bch_alloc_v3, flags, 0, 1) 993 LE32_BITMASK(BCH_ALLOC_V3_NEED_INC_GEN,struct bch_alloc_v3, flags, 1, 2) 994 995 struct bch_alloc_v4 { 996 struct bch_val v; 997 __u64 journal_seq; 998 __u32 flags; 999 __u8 gen; 1000 __u8 oldest_gen; 1001 __u8 data_type; 1002 __u8 stripe_redundancy; 1003 __u32 dirty_sectors; 1004 __u32 cached_sectors; 1005 __u64 io_time[2]; 1006 __u32 stripe; 1007 __u32 nr_external_backpointers; 1008 __u64 fragmentation_lru; 1009 } __packed __aligned(8); 1010 1011 #define BCH_ALLOC_V4_U64s_V0 6 1012 #define BCH_ALLOC_V4_U64s (sizeof(struct bch_alloc_v4) / sizeof(__u64)) 1013 1014 BITMASK(BCH_ALLOC_V4_NEED_DISCARD, struct bch_alloc_v4, flags, 0, 1) 1015 BITMASK(BCH_ALLOC_V4_NEED_INC_GEN, struct bch_alloc_v4, flags, 1, 2) 1016 BITMASK(BCH_ALLOC_V4_BACKPOINTERS_START,struct bch_alloc_v4, flags, 2, 8) 1017 BITMASK(BCH_ALLOC_V4_NR_BACKPOINTERS, struct bch_alloc_v4, flags, 8, 14) 1018 1019 #define BCH_ALLOC_V4_NR_BACKPOINTERS_MAX 40 1020 1021 struct bch_backpointer { 1022 struct bch_val v; 1023 __u8 btree_id; 1024 __u8 level; 1025 __u8 data_type; 1026 __u64 bucket_offset:40; 1027 __u32 bucket_len; 1028 struct bpos pos; 1029 } __packed __aligned(8); 1030 1031 #define KEY_TYPE_BUCKET_GENS_BITS 8 1032 #define KEY_TYPE_BUCKET_GENS_NR (1U << KEY_TYPE_BUCKET_GENS_BITS) 1033 #define KEY_TYPE_BUCKET_GENS_MASK (KEY_TYPE_BUCKET_GENS_NR - 1) 1034 1035 struct bch_bucket_gens { 1036 struct bch_val v; 1037 u8 gens[KEY_TYPE_BUCKET_GENS_NR]; 1038 } __packed __aligned(8); 1039 1040 /* Quotas: */ 1041 1042 enum quota_types { 1043 QTYP_USR = 0, 1044 QTYP_GRP = 1, 1045 QTYP_PRJ = 2, 1046 QTYP_NR = 3, 1047 }; 1048 1049 enum quota_counters { 1050 Q_SPC = 0, 1051 Q_INO = 1, 1052 Q_COUNTERS = 2, 1053 }; 1054 1055 struct bch_quota_counter { 1056 __le64 hardlimit; 1057 __le64 softlimit; 1058 }; 1059 1060 struct bch_quota { 1061 struct bch_val v; 1062 struct bch_quota_counter c[Q_COUNTERS]; 1063 } __packed __aligned(8); 1064 1065 /* Erasure coding */ 1066 1067 struct bch_stripe { 1068 struct bch_val v; 1069 __le16 sectors; 1070 __u8 algorithm; 1071 __u8 nr_blocks; 1072 __u8 nr_redundant; 1073 1074 __u8 csum_granularity_bits; 1075 __u8 csum_type; 1076 __u8 pad; 1077 1078 struct bch_extent_ptr ptrs[]; 1079 } __packed __aligned(8); 1080 1081 /* Reflink: */ 1082 1083 struct bch_reflink_p { 1084 struct bch_val v; 1085 __le64 idx; 1086 /* 1087 * A reflink pointer might point to an indirect extent which is then 1088 * later split (by copygc or rebalance). If we only pointed to part of 1089 * the original indirect extent, and then one of the fragments is 1090 * outside the range we point to, we'd leak a refcount: so when creating 1091 * reflink pointers, we need to store pad values to remember the full 1092 * range we were taking a reference on. 1093 */ 1094 __le32 front_pad; 1095 __le32 back_pad; 1096 } __packed __aligned(8); 1097 1098 struct bch_reflink_v { 1099 struct bch_val v; 1100 __le64 refcount; 1101 union bch_extent_entry start[0]; 1102 __u64 _data[]; 1103 } __packed __aligned(8); 1104 1105 struct bch_indirect_inline_data { 1106 struct bch_val v; 1107 __le64 refcount; 1108 u8 data[]; 1109 }; 1110 1111 /* Inline data */ 1112 1113 struct bch_inline_data { 1114 struct bch_val v; 1115 u8 data[]; 1116 }; 1117 1118 /* Subvolumes: */ 1119 1120 #define SUBVOL_POS_MIN POS(0, 1) 1121 #define SUBVOL_POS_MAX POS(0, S32_MAX) 1122 #define BCACHEFS_ROOT_SUBVOL 1 1123 1124 struct bch_subvolume { 1125 struct bch_val v; 1126 __le32 flags; 1127 __le32 snapshot; 1128 __le64 inode; 1129 /* 1130 * Snapshot subvolumes form a tree, separate from the snapshot nodes 1131 * tree - if this subvolume is a snapshot, this is the ID of the 1132 * subvolume it was created from: 1133 */ 1134 __le32 parent; 1135 __le32 pad; 1136 bch_le128 otime; 1137 }; 1138 1139 LE32_BITMASK(BCH_SUBVOLUME_RO, struct bch_subvolume, flags, 0, 1) 1140 /* 1141 * We need to know whether a subvolume is a snapshot so we can know whether we 1142 * can delete it (or whether it should just be rm -rf'd) 1143 */ 1144 LE32_BITMASK(BCH_SUBVOLUME_SNAP, struct bch_subvolume, flags, 1, 2) 1145 LE32_BITMASK(BCH_SUBVOLUME_UNLINKED, struct bch_subvolume, flags, 2, 3) 1146 1147 /* Snapshots */ 1148 1149 struct bch_snapshot { 1150 struct bch_val v; 1151 __le32 flags; 1152 __le32 parent; 1153 __le32 children[2]; 1154 __le32 subvol; 1155 /* corresponds to a bch_snapshot_tree in BTREE_ID_snapshot_trees */ 1156 __le32 tree; 1157 __le32 depth; 1158 __le32 skip[3]; 1159 }; 1160 1161 LE32_BITMASK(BCH_SNAPSHOT_DELETED, struct bch_snapshot, flags, 0, 1) 1162 1163 /* True if a subvolume points to this snapshot node: */ 1164 LE32_BITMASK(BCH_SNAPSHOT_SUBVOL, struct bch_snapshot, flags, 1, 2) 1165 1166 /* 1167 * Snapshot trees: 1168 * 1169 * The snapshot_trees btree gives us persistent indentifier for each tree of 1170 * bch_snapshot nodes, and allow us to record and easily find the root/master 1171 * subvolume that other snapshots were created from: 1172 */ 1173 struct bch_snapshot_tree { 1174 struct bch_val v; 1175 __le32 master_subvol; 1176 __le32 root_snapshot; 1177 }; 1178 1179 /* LRU btree: */ 1180 1181 struct bch_lru { 1182 struct bch_val v; 1183 __le64 idx; 1184 } __packed __aligned(8); 1185 1186 #define LRU_ID_STRIPES (1U << 16) 1187 1188 /* Logged operations btree: */ 1189 1190 struct bch_logged_op_truncate { 1191 struct bch_val v; 1192 __le32 subvol; 1193 __le32 pad; 1194 __le64 inum; 1195 __le64 new_i_size; 1196 }; 1197 1198 enum logged_op_finsert_state { 1199 LOGGED_OP_FINSERT_start, 1200 LOGGED_OP_FINSERT_shift_extents, 1201 LOGGED_OP_FINSERT_finish, 1202 }; 1203 1204 struct bch_logged_op_finsert { 1205 struct bch_val v; 1206 __u8 state; 1207 __u8 pad[3]; 1208 __le32 subvol; 1209 __le64 inum; 1210 __le64 dst_offset; 1211 __le64 src_offset; 1212 __le64 pos; 1213 }; 1214 1215 /* Optional/variable size superblock sections: */ 1216 1217 struct bch_sb_field { 1218 __u64 _data[0]; 1219 __le32 u64s; 1220 __le32 type; 1221 }; 1222 1223 #define BCH_SB_FIELDS() \ 1224 x(journal, 0) \ 1225 x(members_v1, 1) \ 1226 x(crypt, 2) \ 1227 x(replicas_v0, 3) \ 1228 x(quota, 4) \ 1229 x(disk_groups, 5) \ 1230 x(clean, 6) \ 1231 x(replicas, 7) \ 1232 x(journal_seq_blacklist, 8) \ 1233 x(journal_v2, 9) \ 1234 x(counters, 10) \ 1235 x(members_v2, 11) 1236 1237 enum bch_sb_field_type { 1238 #define x(f, nr) BCH_SB_FIELD_##f = nr, 1239 BCH_SB_FIELDS() 1240 #undef x 1241 BCH_SB_FIELD_NR 1242 }; 1243 1244 /* 1245 * Most superblock fields are replicated in all device's superblocks - a few are 1246 * not: 1247 */ 1248 #define BCH_SINGLE_DEVICE_SB_FIELDS \ 1249 ((1U << BCH_SB_FIELD_journal)| \ 1250 (1U << BCH_SB_FIELD_journal_v2)) 1251 1252 /* BCH_SB_FIELD_journal: */ 1253 1254 struct bch_sb_field_journal { 1255 struct bch_sb_field field; 1256 __le64 buckets[]; 1257 }; 1258 1259 struct bch_sb_field_journal_v2 { 1260 struct bch_sb_field field; 1261 1262 struct bch_sb_field_journal_v2_entry { 1263 __le64 start; 1264 __le64 nr; 1265 } d[]; 1266 }; 1267 1268 /* BCH_SB_FIELD_members_v1: */ 1269 1270 #define BCH_MIN_NR_NBUCKETS (1 << 6) 1271 1272 #define BCH_IOPS_MEASUREMENTS() \ 1273 x(seqread, 0) \ 1274 x(seqwrite, 1) \ 1275 x(randread, 2) \ 1276 x(randwrite, 3) 1277 1278 enum bch_iops_measurement { 1279 #define x(t, n) BCH_IOPS_##t = n, 1280 BCH_IOPS_MEASUREMENTS() 1281 #undef x 1282 BCH_IOPS_NR 1283 }; 1284 1285 struct bch_member { 1286 __uuid_t uuid; 1287 __le64 nbuckets; /* device size */ 1288 __le16 first_bucket; /* index of first bucket used */ 1289 __le16 bucket_size; /* sectors */ 1290 __le32 pad; 1291 __le64 last_mount; /* time_t */ 1292 1293 __le64 flags; 1294 __le32 iops[4]; 1295 }; 1296 1297 #define BCH_MEMBER_V1_BYTES 56 1298 1299 LE64_BITMASK(BCH_MEMBER_STATE, struct bch_member, flags, 0, 4) 1300 /* 4-14 unused, was TIER, HAS_(META)DATA, REPLACEMENT */ 1301 LE64_BITMASK(BCH_MEMBER_DISCARD, struct bch_member, flags, 14, 15) 1302 LE64_BITMASK(BCH_MEMBER_DATA_ALLOWED, struct bch_member, flags, 15, 20) 1303 LE64_BITMASK(BCH_MEMBER_GROUP, struct bch_member, flags, 20, 28) 1304 LE64_BITMASK(BCH_MEMBER_DURABILITY, struct bch_member, flags, 28, 30) 1305 LE64_BITMASK(BCH_MEMBER_FREESPACE_INITIALIZED, 1306 struct bch_member, flags, 30, 31) 1307 1308 #if 0 1309 LE64_BITMASK(BCH_MEMBER_NR_READ_ERRORS, struct bch_member, flags[1], 0, 20); 1310 LE64_BITMASK(BCH_MEMBER_NR_WRITE_ERRORS,struct bch_member, flags[1], 20, 40); 1311 #endif 1312 1313 #define BCH_MEMBER_STATES() \ 1314 x(rw, 0) \ 1315 x(ro, 1) \ 1316 x(failed, 2) \ 1317 x(spare, 3) 1318 1319 enum bch_member_state { 1320 #define x(t, n) BCH_MEMBER_STATE_##t = n, 1321 BCH_MEMBER_STATES() 1322 #undef x 1323 BCH_MEMBER_STATE_NR 1324 }; 1325 1326 struct bch_sb_field_members_v1 { 1327 struct bch_sb_field field; 1328 struct bch_member _members[]; //Members are now variable size 1329 }; 1330 1331 struct bch_sb_field_members_v2 { 1332 struct bch_sb_field field; 1333 __le16 member_bytes; //size of single member entry 1334 u8 pad[6]; 1335 struct bch_member _members[]; 1336 }; 1337 1338 /* BCH_SB_FIELD_crypt: */ 1339 1340 struct nonce { 1341 __le32 d[4]; 1342 }; 1343 1344 struct bch_key { 1345 __le64 key[4]; 1346 }; 1347 1348 #define BCH_KEY_MAGIC \ 1349 (((__u64) 'b' << 0)|((__u64) 'c' << 8)| \ 1350 ((__u64) 'h' << 16)|((__u64) '*' << 24)| \ 1351 ((__u64) '*' << 32)|((__u64) 'k' << 40)| \ 1352 ((__u64) 'e' << 48)|((__u64) 'y' << 56)) 1353 1354 struct bch_encrypted_key { 1355 __le64 magic; 1356 struct bch_key key; 1357 }; 1358 1359 /* 1360 * If this field is present in the superblock, it stores an encryption key which 1361 * is used encrypt all other data/metadata. The key will normally be encrypted 1362 * with the key userspace provides, but if encryption has been turned off we'll 1363 * just store the master key unencrypted in the superblock so we can access the 1364 * previously encrypted data. 1365 */ 1366 struct bch_sb_field_crypt { 1367 struct bch_sb_field field; 1368 1369 __le64 flags; 1370 __le64 kdf_flags; 1371 struct bch_encrypted_key key; 1372 }; 1373 1374 LE64_BITMASK(BCH_CRYPT_KDF_TYPE, struct bch_sb_field_crypt, flags, 0, 4); 1375 1376 enum bch_kdf_types { 1377 BCH_KDF_SCRYPT = 0, 1378 BCH_KDF_NR = 1, 1379 }; 1380 1381 /* stored as base 2 log of scrypt params: */ 1382 LE64_BITMASK(BCH_KDF_SCRYPT_N, struct bch_sb_field_crypt, kdf_flags, 0, 16); 1383 LE64_BITMASK(BCH_KDF_SCRYPT_R, struct bch_sb_field_crypt, kdf_flags, 16, 32); 1384 LE64_BITMASK(BCH_KDF_SCRYPT_P, struct bch_sb_field_crypt, kdf_flags, 32, 48); 1385 1386 /* BCH_SB_FIELD_replicas: */ 1387 1388 #define BCH_DATA_TYPES() \ 1389 x(free, 0) \ 1390 x(sb, 1) \ 1391 x(journal, 2) \ 1392 x(btree, 3) \ 1393 x(user, 4) \ 1394 x(cached, 5) \ 1395 x(parity, 6) \ 1396 x(stripe, 7) \ 1397 x(need_gc_gens, 8) \ 1398 x(need_discard, 9) 1399 1400 enum bch_data_type { 1401 #define x(t, n) BCH_DATA_##t, 1402 BCH_DATA_TYPES() 1403 #undef x 1404 BCH_DATA_NR 1405 }; 1406 1407 static inline bool data_type_is_empty(enum bch_data_type type) 1408 { 1409 switch (type) { 1410 case BCH_DATA_free: 1411 case BCH_DATA_need_gc_gens: 1412 case BCH_DATA_need_discard: 1413 return true; 1414 default: 1415 return false; 1416 } 1417 } 1418 1419 static inline bool data_type_is_hidden(enum bch_data_type type) 1420 { 1421 switch (type) { 1422 case BCH_DATA_sb: 1423 case BCH_DATA_journal: 1424 return true; 1425 default: 1426 return false; 1427 } 1428 } 1429 1430 struct bch_replicas_entry_v0 { 1431 __u8 data_type; 1432 __u8 nr_devs; 1433 __u8 devs[]; 1434 } __packed; 1435 1436 struct bch_sb_field_replicas_v0 { 1437 struct bch_sb_field field; 1438 struct bch_replicas_entry_v0 entries[]; 1439 } __packed __aligned(8); 1440 1441 struct bch_replicas_entry { 1442 __u8 data_type; 1443 __u8 nr_devs; 1444 __u8 nr_required; 1445 __u8 devs[]; 1446 } __packed; 1447 1448 #define replicas_entry_bytes(_i) \ 1449 (offsetof(typeof(*(_i)), devs) + (_i)->nr_devs) 1450 1451 struct bch_sb_field_replicas { 1452 struct bch_sb_field field; 1453 struct bch_replicas_entry entries[]; 1454 } __packed __aligned(8); 1455 1456 /* BCH_SB_FIELD_quota: */ 1457 1458 struct bch_sb_quota_counter { 1459 __le32 timelimit; 1460 __le32 warnlimit; 1461 }; 1462 1463 struct bch_sb_quota_type { 1464 __le64 flags; 1465 struct bch_sb_quota_counter c[Q_COUNTERS]; 1466 }; 1467 1468 struct bch_sb_field_quota { 1469 struct bch_sb_field field; 1470 struct bch_sb_quota_type q[QTYP_NR]; 1471 } __packed __aligned(8); 1472 1473 /* BCH_SB_FIELD_disk_groups: */ 1474 1475 #define BCH_SB_LABEL_SIZE 32 1476 1477 struct bch_disk_group { 1478 __u8 label[BCH_SB_LABEL_SIZE]; 1479 __le64 flags[2]; 1480 } __packed __aligned(8); 1481 1482 LE64_BITMASK(BCH_GROUP_DELETED, struct bch_disk_group, flags[0], 0, 1) 1483 LE64_BITMASK(BCH_GROUP_DATA_ALLOWED, struct bch_disk_group, flags[0], 1, 6) 1484 LE64_BITMASK(BCH_GROUP_PARENT, struct bch_disk_group, flags[0], 6, 24) 1485 1486 struct bch_sb_field_disk_groups { 1487 struct bch_sb_field field; 1488 struct bch_disk_group entries[]; 1489 } __packed __aligned(8); 1490 1491 /* BCH_SB_FIELD_counters */ 1492 1493 #define BCH_PERSISTENT_COUNTERS() \ 1494 x(io_read, 0) \ 1495 x(io_write, 1) \ 1496 x(io_move, 2) \ 1497 x(bucket_invalidate, 3) \ 1498 x(bucket_discard, 4) \ 1499 x(bucket_alloc, 5) \ 1500 x(bucket_alloc_fail, 6) \ 1501 x(btree_cache_scan, 7) \ 1502 x(btree_cache_reap, 8) \ 1503 x(btree_cache_cannibalize, 9) \ 1504 x(btree_cache_cannibalize_lock, 10) \ 1505 x(btree_cache_cannibalize_lock_fail, 11) \ 1506 x(btree_cache_cannibalize_unlock, 12) \ 1507 x(btree_node_write, 13) \ 1508 x(btree_node_read, 14) \ 1509 x(btree_node_compact, 15) \ 1510 x(btree_node_merge, 16) \ 1511 x(btree_node_split, 17) \ 1512 x(btree_node_rewrite, 18) \ 1513 x(btree_node_alloc, 19) \ 1514 x(btree_node_free, 20) \ 1515 x(btree_node_set_root, 21) \ 1516 x(btree_path_relock_fail, 22) \ 1517 x(btree_path_upgrade_fail, 23) \ 1518 x(btree_reserve_get_fail, 24) \ 1519 x(journal_entry_full, 25) \ 1520 x(journal_full, 26) \ 1521 x(journal_reclaim_finish, 27) \ 1522 x(journal_reclaim_start, 28) \ 1523 x(journal_write, 29) \ 1524 x(read_promote, 30) \ 1525 x(read_bounce, 31) \ 1526 x(read_split, 33) \ 1527 x(read_retry, 32) \ 1528 x(read_reuse_race, 34) \ 1529 x(move_extent_read, 35) \ 1530 x(move_extent_write, 36) \ 1531 x(move_extent_finish, 37) \ 1532 x(move_extent_fail, 38) \ 1533 x(move_extent_alloc_mem_fail, 39) \ 1534 x(copygc, 40) \ 1535 x(copygc_wait, 41) \ 1536 x(gc_gens_end, 42) \ 1537 x(gc_gens_start, 43) \ 1538 x(trans_blocked_journal_reclaim, 44) \ 1539 x(trans_restart_btree_node_reused, 45) \ 1540 x(trans_restart_btree_node_split, 46) \ 1541 x(trans_restart_fault_inject, 47) \ 1542 x(trans_restart_iter_upgrade, 48) \ 1543 x(trans_restart_journal_preres_get, 49) \ 1544 x(trans_restart_journal_reclaim, 50) \ 1545 x(trans_restart_journal_res_get, 51) \ 1546 x(trans_restart_key_cache_key_realloced, 52) \ 1547 x(trans_restart_key_cache_raced, 53) \ 1548 x(trans_restart_mark_replicas, 54) \ 1549 x(trans_restart_mem_realloced, 55) \ 1550 x(trans_restart_memory_allocation_failure, 56) \ 1551 x(trans_restart_relock, 57) \ 1552 x(trans_restart_relock_after_fill, 58) \ 1553 x(trans_restart_relock_key_cache_fill, 59) \ 1554 x(trans_restart_relock_next_node, 60) \ 1555 x(trans_restart_relock_parent_for_fill, 61) \ 1556 x(trans_restart_relock_path, 62) \ 1557 x(trans_restart_relock_path_intent, 63) \ 1558 x(trans_restart_too_many_iters, 64) \ 1559 x(trans_restart_traverse, 65) \ 1560 x(trans_restart_upgrade, 66) \ 1561 x(trans_restart_would_deadlock, 67) \ 1562 x(trans_restart_would_deadlock_write, 68) \ 1563 x(trans_restart_injected, 69) \ 1564 x(trans_restart_key_cache_upgrade, 70) \ 1565 x(trans_traverse_all, 71) \ 1566 x(transaction_commit, 72) \ 1567 x(write_super, 73) \ 1568 x(trans_restart_would_deadlock_recursion_limit, 74) \ 1569 x(trans_restart_write_buffer_flush, 75) \ 1570 x(trans_restart_split_race, 76) 1571 1572 enum bch_persistent_counters { 1573 #define x(t, n, ...) BCH_COUNTER_##t, 1574 BCH_PERSISTENT_COUNTERS() 1575 #undef x 1576 BCH_COUNTER_NR 1577 }; 1578 1579 struct bch_sb_field_counters { 1580 struct bch_sb_field field; 1581 __le64 d[]; 1582 }; 1583 1584 /* 1585 * On clean shutdown, store btree roots and current journal sequence number in 1586 * the superblock: 1587 */ 1588 struct jset_entry { 1589 __le16 u64s; 1590 __u8 btree_id; 1591 __u8 level; 1592 __u8 type; /* designates what this jset holds */ 1593 __u8 pad[3]; 1594 1595 struct bkey_i start[0]; 1596 __u64 _data[]; 1597 }; 1598 1599 struct bch_sb_field_clean { 1600 struct bch_sb_field field; 1601 1602 __le32 flags; 1603 __le16 _read_clock; /* no longer used */ 1604 __le16 _write_clock; 1605 __le64 journal_seq; 1606 1607 struct jset_entry start[0]; 1608 __u64 _data[]; 1609 }; 1610 1611 struct journal_seq_blacklist_entry { 1612 __le64 start; 1613 __le64 end; 1614 }; 1615 1616 struct bch_sb_field_journal_seq_blacklist { 1617 struct bch_sb_field field; 1618 1619 struct journal_seq_blacklist_entry start[0]; 1620 __u64 _data[]; 1621 }; 1622 1623 /* Superblock: */ 1624 1625 /* 1626 * New versioning scheme: 1627 * One common version number for all on disk data structures - superblock, btree 1628 * nodes, journal entries 1629 */ 1630 #define BCH_VERSION_MAJOR(_v) ((__u16) ((_v) >> 10)) 1631 #define BCH_VERSION_MINOR(_v) ((__u16) ((_v) & ~(~0U << 10))) 1632 #define BCH_VERSION(_major, _minor) (((_major) << 10)|(_minor) << 0) 1633 1634 #define RECOVERY_PASS_ALL_FSCK (1ULL << 63) 1635 1636 #define BCH_METADATA_VERSIONS() \ 1637 x(bkey_renumber, BCH_VERSION(0, 10), \ 1638 RECOVERY_PASS_ALL_FSCK) \ 1639 x(inode_btree_change, BCH_VERSION(0, 11), \ 1640 RECOVERY_PASS_ALL_FSCK) \ 1641 x(snapshot, BCH_VERSION(0, 12), \ 1642 RECOVERY_PASS_ALL_FSCK) \ 1643 x(inode_backpointers, BCH_VERSION(0, 13), \ 1644 RECOVERY_PASS_ALL_FSCK) \ 1645 x(btree_ptr_sectors_written, BCH_VERSION(0, 14), \ 1646 RECOVERY_PASS_ALL_FSCK) \ 1647 x(snapshot_2, BCH_VERSION(0, 15), \ 1648 BIT_ULL(BCH_RECOVERY_PASS_fs_upgrade_for_subvolumes)| \ 1649 BIT_ULL(BCH_RECOVERY_PASS_initialize_subvolumes)| \ 1650 RECOVERY_PASS_ALL_FSCK) \ 1651 x(reflink_p_fix, BCH_VERSION(0, 16), \ 1652 BIT_ULL(BCH_RECOVERY_PASS_fix_reflink_p)) \ 1653 x(subvol_dirent, BCH_VERSION(0, 17), \ 1654 RECOVERY_PASS_ALL_FSCK) \ 1655 x(inode_v2, BCH_VERSION(0, 18), \ 1656 RECOVERY_PASS_ALL_FSCK) \ 1657 x(freespace, BCH_VERSION(0, 19), \ 1658 RECOVERY_PASS_ALL_FSCK) \ 1659 x(alloc_v4, BCH_VERSION(0, 20), \ 1660 RECOVERY_PASS_ALL_FSCK) \ 1661 x(new_data_types, BCH_VERSION(0, 21), \ 1662 RECOVERY_PASS_ALL_FSCK) \ 1663 x(backpointers, BCH_VERSION(0, 22), \ 1664 RECOVERY_PASS_ALL_FSCK) \ 1665 x(inode_v3, BCH_VERSION(0, 23), \ 1666 RECOVERY_PASS_ALL_FSCK) \ 1667 x(unwritten_extents, BCH_VERSION(0, 24), \ 1668 RECOVERY_PASS_ALL_FSCK) \ 1669 x(bucket_gens, BCH_VERSION(0, 25), \ 1670 BIT_ULL(BCH_RECOVERY_PASS_bucket_gens_init)| \ 1671 RECOVERY_PASS_ALL_FSCK) \ 1672 x(lru_v2, BCH_VERSION(0, 26), \ 1673 RECOVERY_PASS_ALL_FSCK) \ 1674 x(fragmentation_lru, BCH_VERSION(0, 27), \ 1675 RECOVERY_PASS_ALL_FSCK) \ 1676 x(no_bps_in_alloc_keys, BCH_VERSION(0, 28), \ 1677 RECOVERY_PASS_ALL_FSCK) \ 1678 x(snapshot_trees, BCH_VERSION(0, 29), \ 1679 RECOVERY_PASS_ALL_FSCK) \ 1680 x(major_minor, BCH_VERSION(1, 0), \ 1681 0) \ 1682 x(snapshot_skiplists, BCH_VERSION(1, 1), \ 1683 BIT_ULL(BCH_RECOVERY_PASS_check_snapshots)) \ 1684 x(deleted_inodes, BCH_VERSION(1, 2), \ 1685 BIT_ULL(BCH_RECOVERY_PASS_check_inodes)) 1686 1687 enum bcachefs_metadata_version { 1688 bcachefs_metadata_version_min = 9, 1689 #define x(t, n, upgrade_passes) bcachefs_metadata_version_##t = n, 1690 BCH_METADATA_VERSIONS() 1691 #undef x 1692 bcachefs_metadata_version_max 1693 }; 1694 1695 static const __maybe_unused 1696 unsigned bcachefs_metadata_required_upgrade_below = bcachefs_metadata_version_major_minor; 1697 1698 #define bcachefs_metadata_version_current (bcachefs_metadata_version_max - 1) 1699 1700 #define BCH_SB_SECTOR 8 1701 #define BCH_SB_MEMBERS_MAX 64 /* XXX kill */ 1702 1703 struct bch_sb_layout { 1704 __uuid_t magic; /* bcachefs superblock UUID */ 1705 __u8 layout_type; 1706 __u8 sb_max_size_bits; /* base 2 of 512 byte sectors */ 1707 __u8 nr_superblocks; 1708 __u8 pad[5]; 1709 __le64 sb_offset[61]; 1710 } __packed __aligned(8); 1711 1712 #define BCH_SB_LAYOUT_SECTOR 7 1713 1714 /* 1715 * @offset - sector where this sb was written 1716 * @version - on disk format version 1717 * @version_min - Oldest metadata version this filesystem contains; so we can 1718 * safely drop compatibility code and refuse to mount filesystems 1719 * we'd need it for 1720 * @magic - identifies as a bcachefs superblock (BCHFS_MAGIC) 1721 * @seq - incremented each time superblock is written 1722 * @uuid - used for generating various magic numbers and identifying 1723 * member devices, never changes 1724 * @user_uuid - user visible UUID, may be changed 1725 * @label - filesystem label 1726 * @seq - identifies most recent superblock, incremented each time 1727 * superblock is written 1728 * @features - enabled incompatible features 1729 */ 1730 struct bch_sb { 1731 struct bch_csum csum; 1732 __le16 version; 1733 __le16 version_min; 1734 __le16 pad[2]; 1735 __uuid_t magic; 1736 __uuid_t uuid; 1737 __uuid_t user_uuid; 1738 __u8 label[BCH_SB_LABEL_SIZE]; 1739 __le64 offset; 1740 __le64 seq; 1741 1742 __le16 block_size; 1743 __u8 dev_idx; 1744 __u8 nr_devices; 1745 __le32 u64s; 1746 1747 __le64 time_base_lo; 1748 __le32 time_base_hi; 1749 __le32 time_precision; 1750 1751 __le64 flags[8]; 1752 __le64 features[2]; 1753 __le64 compat[2]; 1754 1755 struct bch_sb_layout layout; 1756 1757 struct bch_sb_field start[0]; 1758 __le64 _data[]; 1759 } __packed __aligned(8); 1760 1761 /* 1762 * Flags: 1763 * BCH_SB_INITALIZED - set on first mount 1764 * BCH_SB_CLEAN - did we shut down cleanly? Just a hint, doesn't affect 1765 * behaviour of mount/recovery path: 1766 * BCH_SB_INODE_32BIT - limit inode numbers to 32 bits 1767 * BCH_SB_128_BIT_MACS - 128 bit macs instead of 80 1768 * BCH_SB_ENCRYPTION_TYPE - if nonzero encryption is enabled; overrides 1769 * DATA/META_CSUM_TYPE. Also indicates encryption 1770 * algorithm in use, if/when we get more than one 1771 */ 1772 1773 LE16_BITMASK(BCH_SB_BLOCK_SIZE, struct bch_sb, block_size, 0, 16); 1774 1775 LE64_BITMASK(BCH_SB_INITIALIZED, struct bch_sb, flags[0], 0, 1); 1776 LE64_BITMASK(BCH_SB_CLEAN, struct bch_sb, flags[0], 1, 2); 1777 LE64_BITMASK(BCH_SB_CSUM_TYPE, struct bch_sb, flags[0], 2, 8); 1778 LE64_BITMASK(BCH_SB_ERROR_ACTION, struct bch_sb, flags[0], 8, 12); 1779 1780 LE64_BITMASK(BCH_SB_BTREE_NODE_SIZE, struct bch_sb, flags[0], 12, 28); 1781 1782 LE64_BITMASK(BCH_SB_GC_RESERVE, struct bch_sb, flags[0], 28, 33); 1783 LE64_BITMASK(BCH_SB_ROOT_RESERVE, struct bch_sb, flags[0], 33, 40); 1784 1785 LE64_BITMASK(BCH_SB_META_CSUM_TYPE, struct bch_sb, flags[0], 40, 44); 1786 LE64_BITMASK(BCH_SB_DATA_CSUM_TYPE, struct bch_sb, flags[0], 44, 48); 1787 1788 LE64_BITMASK(BCH_SB_META_REPLICAS_WANT, struct bch_sb, flags[0], 48, 52); 1789 LE64_BITMASK(BCH_SB_DATA_REPLICAS_WANT, struct bch_sb, flags[0], 52, 56); 1790 1791 LE64_BITMASK(BCH_SB_POSIX_ACL, struct bch_sb, flags[0], 56, 57); 1792 LE64_BITMASK(BCH_SB_USRQUOTA, struct bch_sb, flags[0], 57, 58); 1793 LE64_BITMASK(BCH_SB_GRPQUOTA, struct bch_sb, flags[0], 58, 59); 1794 LE64_BITMASK(BCH_SB_PRJQUOTA, struct bch_sb, flags[0], 59, 60); 1795 1796 LE64_BITMASK(BCH_SB_HAS_ERRORS, struct bch_sb, flags[0], 60, 61); 1797 LE64_BITMASK(BCH_SB_HAS_TOPOLOGY_ERRORS,struct bch_sb, flags[0], 61, 62); 1798 1799 LE64_BITMASK(BCH_SB_BIG_ENDIAN, struct bch_sb, flags[0], 62, 63); 1800 1801 LE64_BITMASK(BCH_SB_STR_HASH_TYPE, struct bch_sb, flags[1], 0, 4); 1802 LE64_BITMASK(BCH_SB_COMPRESSION_TYPE_LO,struct bch_sb, flags[1], 4, 8); 1803 LE64_BITMASK(BCH_SB_INODE_32BIT, struct bch_sb, flags[1], 8, 9); 1804 1805 LE64_BITMASK(BCH_SB_128_BIT_MACS, struct bch_sb, flags[1], 9, 10); 1806 LE64_BITMASK(BCH_SB_ENCRYPTION_TYPE, struct bch_sb, flags[1], 10, 14); 1807 1808 /* 1809 * Max size of an extent that may require bouncing to read or write 1810 * (checksummed, compressed): 64k 1811 */ 1812 LE64_BITMASK(BCH_SB_ENCODED_EXTENT_MAX_BITS, 1813 struct bch_sb, flags[1], 14, 20); 1814 1815 LE64_BITMASK(BCH_SB_META_REPLICAS_REQ, struct bch_sb, flags[1], 20, 24); 1816 LE64_BITMASK(BCH_SB_DATA_REPLICAS_REQ, struct bch_sb, flags[1], 24, 28); 1817 1818 LE64_BITMASK(BCH_SB_PROMOTE_TARGET, struct bch_sb, flags[1], 28, 40); 1819 LE64_BITMASK(BCH_SB_FOREGROUND_TARGET, struct bch_sb, flags[1], 40, 52); 1820 LE64_BITMASK(BCH_SB_BACKGROUND_TARGET, struct bch_sb, flags[1], 52, 64); 1821 1822 LE64_BITMASK(BCH_SB_BACKGROUND_COMPRESSION_TYPE_LO, 1823 struct bch_sb, flags[2], 0, 4); 1824 LE64_BITMASK(BCH_SB_GC_RESERVE_BYTES, struct bch_sb, flags[2], 4, 64); 1825 1826 LE64_BITMASK(BCH_SB_ERASURE_CODE, struct bch_sb, flags[3], 0, 16); 1827 LE64_BITMASK(BCH_SB_METADATA_TARGET, struct bch_sb, flags[3], 16, 28); 1828 LE64_BITMASK(BCH_SB_SHARD_INUMS, struct bch_sb, flags[3], 28, 29); 1829 LE64_BITMASK(BCH_SB_INODES_USE_KEY_CACHE,struct bch_sb, flags[3], 29, 30); 1830 LE64_BITMASK(BCH_SB_JOURNAL_FLUSH_DELAY,struct bch_sb, flags[3], 30, 62); 1831 LE64_BITMASK(BCH_SB_JOURNAL_FLUSH_DISABLED,struct bch_sb, flags[3], 62, 63); 1832 LE64_BITMASK(BCH_SB_JOURNAL_RECLAIM_DELAY,struct bch_sb, flags[4], 0, 32); 1833 LE64_BITMASK(BCH_SB_JOURNAL_TRANSACTION_NAMES,struct bch_sb, flags[4], 32, 33); 1834 LE64_BITMASK(BCH_SB_NOCOW, struct bch_sb, flags[4], 33, 34); 1835 LE64_BITMASK(BCH_SB_WRITE_BUFFER_SIZE, struct bch_sb, flags[4], 34, 54); 1836 LE64_BITMASK(BCH_SB_VERSION_UPGRADE, struct bch_sb, flags[4], 54, 56); 1837 1838 LE64_BITMASK(BCH_SB_COMPRESSION_TYPE_HI,struct bch_sb, flags[4], 56, 60); 1839 LE64_BITMASK(BCH_SB_BACKGROUND_COMPRESSION_TYPE_HI, 1840 struct bch_sb, flags[4], 60, 64); 1841 1842 LE64_BITMASK(BCH_SB_VERSION_UPGRADE_COMPLETE, 1843 struct bch_sb, flags[5], 0, 16); 1844 1845 static inline __u64 BCH_SB_COMPRESSION_TYPE(const struct bch_sb *sb) 1846 { 1847 return BCH_SB_COMPRESSION_TYPE_LO(sb) | (BCH_SB_COMPRESSION_TYPE_HI(sb) << 4); 1848 } 1849 1850 static inline void SET_BCH_SB_COMPRESSION_TYPE(struct bch_sb *sb, __u64 v) 1851 { 1852 SET_BCH_SB_COMPRESSION_TYPE_LO(sb, v); 1853 SET_BCH_SB_COMPRESSION_TYPE_HI(sb, v >> 4); 1854 } 1855 1856 static inline __u64 BCH_SB_BACKGROUND_COMPRESSION_TYPE(const struct bch_sb *sb) 1857 { 1858 return BCH_SB_BACKGROUND_COMPRESSION_TYPE_LO(sb) | 1859 (BCH_SB_BACKGROUND_COMPRESSION_TYPE_HI(sb) << 4); 1860 } 1861 1862 static inline void SET_BCH_SB_BACKGROUND_COMPRESSION_TYPE(struct bch_sb *sb, __u64 v) 1863 { 1864 SET_BCH_SB_BACKGROUND_COMPRESSION_TYPE_LO(sb, v); 1865 SET_BCH_SB_BACKGROUND_COMPRESSION_TYPE_HI(sb, v >> 4); 1866 } 1867 1868 /* 1869 * Features: 1870 * 1871 * journal_seq_blacklist_v3: gates BCH_SB_FIELD_journal_seq_blacklist 1872 * reflink: gates KEY_TYPE_reflink 1873 * inline_data: gates KEY_TYPE_inline_data 1874 * new_siphash: gates BCH_STR_HASH_siphash 1875 * new_extent_overwrite: gates BTREE_NODE_NEW_EXTENT_OVERWRITE 1876 */ 1877 #define BCH_SB_FEATURES() \ 1878 x(lz4, 0) \ 1879 x(gzip, 1) \ 1880 x(zstd, 2) \ 1881 x(atomic_nlink, 3) \ 1882 x(ec, 4) \ 1883 x(journal_seq_blacklist_v3, 5) \ 1884 x(reflink, 6) \ 1885 x(new_siphash, 7) \ 1886 x(inline_data, 8) \ 1887 x(new_extent_overwrite, 9) \ 1888 x(incompressible, 10) \ 1889 x(btree_ptr_v2, 11) \ 1890 x(extents_above_btree_updates, 12) \ 1891 x(btree_updates_journalled, 13) \ 1892 x(reflink_inline_data, 14) \ 1893 x(new_varint, 15) \ 1894 x(journal_no_flush, 16) \ 1895 x(alloc_v2, 17) \ 1896 x(extents_across_btree_nodes, 18) 1897 1898 #define BCH_SB_FEATURES_ALWAYS \ 1899 ((1ULL << BCH_FEATURE_new_extent_overwrite)| \ 1900 (1ULL << BCH_FEATURE_extents_above_btree_updates)|\ 1901 (1ULL << BCH_FEATURE_btree_updates_journalled)|\ 1902 (1ULL << BCH_FEATURE_alloc_v2)|\ 1903 (1ULL << BCH_FEATURE_extents_across_btree_nodes)) 1904 1905 #define BCH_SB_FEATURES_ALL \ 1906 (BCH_SB_FEATURES_ALWAYS| \ 1907 (1ULL << BCH_FEATURE_new_siphash)| \ 1908 (1ULL << BCH_FEATURE_btree_ptr_v2)| \ 1909 (1ULL << BCH_FEATURE_new_varint)| \ 1910 (1ULL << BCH_FEATURE_journal_no_flush)) 1911 1912 enum bch_sb_feature { 1913 #define x(f, n) BCH_FEATURE_##f, 1914 BCH_SB_FEATURES() 1915 #undef x 1916 BCH_FEATURE_NR, 1917 }; 1918 1919 #define BCH_SB_COMPAT() \ 1920 x(alloc_info, 0) \ 1921 x(alloc_metadata, 1) \ 1922 x(extents_above_btree_updates_done, 2) \ 1923 x(bformat_overflow_done, 3) 1924 1925 enum bch_sb_compat { 1926 #define x(f, n) BCH_COMPAT_##f, 1927 BCH_SB_COMPAT() 1928 #undef x 1929 BCH_COMPAT_NR, 1930 }; 1931 1932 /* options: */ 1933 1934 #define BCH_VERSION_UPGRADE_OPTS() \ 1935 x(compatible, 0) \ 1936 x(incompatible, 1) \ 1937 x(none, 2) 1938 1939 enum bch_version_upgrade_opts { 1940 #define x(t, n) BCH_VERSION_UPGRADE_##t = n, 1941 BCH_VERSION_UPGRADE_OPTS() 1942 #undef x 1943 }; 1944 1945 #define BCH_REPLICAS_MAX 4U 1946 1947 #define BCH_BKEY_PTRS_MAX 16U 1948 1949 #define BCH_ERROR_ACTIONS() \ 1950 x(continue, 0) \ 1951 x(ro, 1) \ 1952 x(panic, 2) 1953 1954 enum bch_error_actions { 1955 #define x(t, n) BCH_ON_ERROR_##t = n, 1956 BCH_ERROR_ACTIONS() 1957 #undef x 1958 BCH_ON_ERROR_NR 1959 }; 1960 1961 #define BCH_STR_HASH_TYPES() \ 1962 x(crc32c, 0) \ 1963 x(crc64, 1) \ 1964 x(siphash_old, 2) \ 1965 x(siphash, 3) 1966 1967 enum bch_str_hash_type { 1968 #define x(t, n) BCH_STR_HASH_##t = n, 1969 BCH_STR_HASH_TYPES() 1970 #undef x 1971 BCH_STR_HASH_NR 1972 }; 1973 1974 #define BCH_STR_HASH_OPTS() \ 1975 x(crc32c, 0) \ 1976 x(crc64, 1) \ 1977 x(siphash, 2) 1978 1979 enum bch_str_hash_opts { 1980 #define x(t, n) BCH_STR_HASH_OPT_##t = n, 1981 BCH_STR_HASH_OPTS() 1982 #undef x 1983 BCH_STR_HASH_OPT_NR 1984 }; 1985 1986 #define BCH_CSUM_TYPES() \ 1987 x(none, 0) \ 1988 x(crc32c_nonzero, 1) \ 1989 x(crc64_nonzero, 2) \ 1990 x(chacha20_poly1305_80, 3) \ 1991 x(chacha20_poly1305_128, 4) \ 1992 x(crc32c, 5) \ 1993 x(crc64, 6) \ 1994 x(xxhash, 7) 1995 1996 enum bch_csum_type { 1997 #define x(t, n) BCH_CSUM_##t = n, 1998 BCH_CSUM_TYPES() 1999 #undef x 2000 BCH_CSUM_NR 2001 }; 2002 2003 static const __maybe_unused unsigned bch_crc_bytes[] = { 2004 [BCH_CSUM_none] = 0, 2005 [BCH_CSUM_crc32c_nonzero] = 4, 2006 [BCH_CSUM_crc32c] = 4, 2007 [BCH_CSUM_crc64_nonzero] = 8, 2008 [BCH_CSUM_crc64] = 8, 2009 [BCH_CSUM_xxhash] = 8, 2010 [BCH_CSUM_chacha20_poly1305_80] = 10, 2011 [BCH_CSUM_chacha20_poly1305_128] = 16, 2012 }; 2013 2014 static inline _Bool bch2_csum_type_is_encryption(enum bch_csum_type type) 2015 { 2016 switch (type) { 2017 case BCH_CSUM_chacha20_poly1305_80: 2018 case BCH_CSUM_chacha20_poly1305_128: 2019 return true; 2020 default: 2021 return false; 2022 } 2023 } 2024 2025 #define BCH_CSUM_OPTS() \ 2026 x(none, 0) \ 2027 x(crc32c, 1) \ 2028 x(crc64, 2) \ 2029 x(xxhash, 3) 2030 2031 enum bch_csum_opts { 2032 #define x(t, n) BCH_CSUM_OPT_##t = n, 2033 BCH_CSUM_OPTS() 2034 #undef x 2035 BCH_CSUM_OPT_NR 2036 }; 2037 2038 #define BCH_COMPRESSION_TYPES() \ 2039 x(none, 0) \ 2040 x(lz4_old, 1) \ 2041 x(gzip, 2) \ 2042 x(lz4, 3) \ 2043 x(zstd, 4) \ 2044 x(incompressible, 5) 2045 2046 enum bch_compression_type { 2047 #define x(t, n) BCH_COMPRESSION_TYPE_##t = n, 2048 BCH_COMPRESSION_TYPES() 2049 #undef x 2050 BCH_COMPRESSION_TYPE_NR 2051 }; 2052 2053 #define BCH_COMPRESSION_OPTS() \ 2054 x(none, 0) \ 2055 x(lz4, 1) \ 2056 x(gzip, 2) \ 2057 x(zstd, 3) 2058 2059 enum bch_compression_opts { 2060 #define x(t, n) BCH_COMPRESSION_OPT_##t = n, 2061 BCH_COMPRESSION_OPTS() 2062 #undef x 2063 BCH_COMPRESSION_OPT_NR 2064 }; 2065 2066 /* 2067 * Magic numbers 2068 * 2069 * The various other data structures have their own magic numbers, which are 2070 * xored with the first part of the cache set's UUID 2071 */ 2072 2073 #define BCACHE_MAGIC \ 2074 UUID_INIT(0xc68573f6, 0x4e1a, 0x45ca, \ 2075 0x82, 0x65, 0xf5, 0x7f, 0x48, 0xba, 0x6d, 0x81) 2076 #define BCHFS_MAGIC \ 2077 UUID_INIT(0xc68573f6, 0x66ce, 0x90a9, \ 2078 0xd9, 0x6a, 0x60, 0xcf, 0x80, 0x3d, 0xf7, 0xef) 2079 2080 #define BCACHEFS_STATFS_MAGIC 0xca451a4e 2081 2082 #define JSET_MAGIC __cpu_to_le64(0x245235c1a3625032ULL) 2083 #define BSET_MAGIC __cpu_to_le64(0x90135c78b99e07f5ULL) 2084 2085 static inline __le64 __bch2_sb_magic(struct bch_sb *sb) 2086 { 2087 __le64 ret; 2088 2089 memcpy(&ret, &sb->uuid, sizeof(ret)); 2090 return ret; 2091 } 2092 2093 static inline __u64 __jset_magic(struct bch_sb *sb) 2094 { 2095 return __le64_to_cpu(__bch2_sb_magic(sb) ^ JSET_MAGIC); 2096 } 2097 2098 static inline __u64 __bset_magic(struct bch_sb *sb) 2099 { 2100 return __le64_to_cpu(__bch2_sb_magic(sb) ^ BSET_MAGIC); 2101 } 2102 2103 /* Journal */ 2104 2105 #define JSET_KEYS_U64s (sizeof(struct jset_entry) / sizeof(__u64)) 2106 2107 #define BCH_JSET_ENTRY_TYPES() \ 2108 x(btree_keys, 0) \ 2109 x(btree_root, 1) \ 2110 x(prio_ptrs, 2) \ 2111 x(blacklist, 3) \ 2112 x(blacklist_v2, 4) \ 2113 x(usage, 5) \ 2114 x(data_usage, 6) \ 2115 x(clock, 7) \ 2116 x(dev_usage, 8) \ 2117 x(log, 9) \ 2118 x(overwrite, 10) 2119 2120 enum { 2121 #define x(f, nr) BCH_JSET_ENTRY_##f = nr, 2122 BCH_JSET_ENTRY_TYPES() 2123 #undef x 2124 BCH_JSET_ENTRY_NR 2125 }; 2126 2127 /* 2128 * Journal sequence numbers can be blacklisted: bsets record the max sequence 2129 * number of all the journal entries they contain updates for, so that on 2130 * recovery we can ignore those bsets that contain index updates newer that what 2131 * made it into the journal. 2132 * 2133 * This means that we can't reuse that journal_seq - we have to skip it, and 2134 * then record that we skipped it so that the next time we crash and recover we 2135 * don't think there was a missing journal entry. 2136 */ 2137 struct jset_entry_blacklist { 2138 struct jset_entry entry; 2139 __le64 seq; 2140 }; 2141 2142 struct jset_entry_blacklist_v2 { 2143 struct jset_entry entry; 2144 __le64 start; 2145 __le64 end; 2146 }; 2147 2148 #define BCH_FS_USAGE_TYPES() \ 2149 x(reserved, 0) \ 2150 x(inodes, 1) \ 2151 x(key_version, 2) 2152 2153 enum { 2154 #define x(f, nr) BCH_FS_USAGE_##f = nr, 2155 BCH_FS_USAGE_TYPES() 2156 #undef x 2157 BCH_FS_USAGE_NR 2158 }; 2159 2160 struct jset_entry_usage { 2161 struct jset_entry entry; 2162 __le64 v; 2163 } __packed; 2164 2165 struct jset_entry_data_usage { 2166 struct jset_entry entry; 2167 __le64 v; 2168 struct bch_replicas_entry r; 2169 } __packed; 2170 2171 struct jset_entry_clock { 2172 struct jset_entry entry; 2173 __u8 rw; 2174 __u8 pad[7]; 2175 __le64 time; 2176 } __packed; 2177 2178 struct jset_entry_dev_usage_type { 2179 __le64 buckets; 2180 __le64 sectors; 2181 __le64 fragmented; 2182 } __packed; 2183 2184 struct jset_entry_dev_usage { 2185 struct jset_entry entry; 2186 __le32 dev; 2187 __u32 pad; 2188 2189 __le64 buckets_ec; 2190 __le64 _buckets_unavailable; /* No longer used */ 2191 2192 struct jset_entry_dev_usage_type d[]; 2193 }; 2194 2195 static inline unsigned jset_entry_dev_usage_nr_types(struct jset_entry_dev_usage *u) 2196 { 2197 return (vstruct_bytes(&u->entry) - sizeof(struct jset_entry_dev_usage)) / 2198 sizeof(struct jset_entry_dev_usage_type); 2199 } 2200 2201 struct jset_entry_log { 2202 struct jset_entry entry; 2203 u8 d[]; 2204 } __packed; 2205 2206 /* 2207 * On disk format for a journal entry: 2208 * seq is monotonically increasing; every journal entry has its own unique 2209 * sequence number. 2210 * 2211 * last_seq is the oldest journal entry that still has keys the btree hasn't 2212 * flushed to disk yet. 2213 * 2214 * version is for on disk format changes. 2215 */ 2216 struct jset { 2217 struct bch_csum csum; 2218 2219 __le64 magic; 2220 __le64 seq; 2221 __le32 version; 2222 __le32 flags; 2223 2224 __le32 u64s; /* size of d[] in u64s */ 2225 2226 __u8 encrypted_start[0]; 2227 2228 __le16 _read_clock; /* no longer used */ 2229 __le16 _write_clock; 2230 2231 /* Sequence number of oldest dirty journal entry */ 2232 __le64 last_seq; 2233 2234 2235 struct jset_entry start[0]; 2236 __u64 _data[]; 2237 } __packed __aligned(8); 2238 2239 LE32_BITMASK(JSET_CSUM_TYPE, struct jset, flags, 0, 4); 2240 LE32_BITMASK(JSET_BIG_ENDIAN, struct jset, flags, 4, 5); 2241 LE32_BITMASK(JSET_NO_FLUSH, struct jset, flags, 5, 6); 2242 2243 #define BCH_JOURNAL_BUCKETS_MIN 8 2244 2245 /* Btree: */ 2246 2247 enum btree_id_flags { 2248 BTREE_ID_EXTENTS = BIT(0), 2249 BTREE_ID_SNAPSHOTS = BIT(1), 2250 BTREE_ID_DATA = BIT(2), 2251 }; 2252 2253 #define BCH_BTREE_IDS() \ 2254 x(extents, 0, BTREE_ID_EXTENTS|BTREE_ID_SNAPSHOTS|BTREE_ID_DATA,\ 2255 BIT_ULL(KEY_TYPE_whiteout)| \ 2256 BIT_ULL(KEY_TYPE_error)| \ 2257 BIT_ULL(KEY_TYPE_cookie)| \ 2258 BIT_ULL(KEY_TYPE_extent)| \ 2259 BIT_ULL(KEY_TYPE_reservation)| \ 2260 BIT_ULL(KEY_TYPE_reflink_p)| \ 2261 BIT_ULL(KEY_TYPE_inline_data)) \ 2262 x(inodes, 1, BTREE_ID_SNAPSHOTS, \ 2263 BIT_ULL(KEY_TYPE_whiteout)| \ 2264 BIT_ULL(KEY_TYPE_inode)| \ 2265 BIT_ULL(KEY_TYPE_inode_v2)| \ 2266 BIT_ULL(KEY_TYPE_inode_v3)| \ 2267 BIT_ULL(KEY_TYPE_inode_generation)) \ 2268 x(dirents, 2, BTREE_ID_SNAPSHOTS, \ 2269 BIT_ULL(KEY_TYPE_whiteout)| \ 2270 BIT_ULL(KEY_TYPE_hash_whiteout)| \ 2271 BIT_ULL(KEY_TYPE_dirent)) \ 2272 x(xattrs, 3, BTREE_ID_SNAPSHOTS, \ 2273 BIT_ULL(KEY_TYPE_whiteout)| \ 2274 BIT_ULL(KEY_TYPE_cookie)| \ 2275 BIT_ULL(KEY_TYPE_hash_whiteout)| \ 2276 BIT_ULL(KEY_TYPE_xattr)) \ 2277 x(alloc, 4, 0, \ 2278 BIT_ULL(KEY_TYPE_alloc)| \ 2279 BIT_ULL(KEY_TYPE_alloc_v2)| \ 2280 BIT_ULL(KEY_TYPE_alloc_v3)| \ 2281 BIT_ULL(KEY_TYPE_alloc_v4)) \ 2282 x(quotas, 5, 0, \ 2283 BIT_ULL(KEY_TYPE_quota)) \ 2284 x(stripes, 6, 0, \ 2285 BIT_ULL(KEY_TYPE_stripe)) \ 2286 x(reflink, 7, BTREE_ID_EXTENTS|BTREE_ID_DATA, \ 2287 BIT_ULL(KEY_TYPE_reflink_v)| \ 2288 BIT_ULL(KEY_TYPE_indirect_inline_data)) \ 2289 x(subvolumes, 8, 0, \ 2290 BIT_ULL(KEY_TYPE_subvolume)) \ 2291 x(snapshots, 9, 0, \ 2292 BIT_ULL(KEY_TYPE_snapshot)) \ 2293 x(lru, 10, 0, \ 2294 BIT_ULL(KEY_TYPE_set)) \ 2295 x(freespace, 11, BTREE_ID_EXTENTS, \ 2296 BIT_ULL(KEY_TYPE_set)) \ 2297 x(need_discard, 12, 0, \ 2298 BIT_ULL(KEY_TYPE_set)) \ 2299 x(backpointers, 13, 0, \ 2300 BIT_ULL(KEY_TYPE_backpointer)) \ 2301 x(bucket_gens, 14, 0, \ 2302 BIT_ULL(KEY_TYPE_bucket_gens)) \ 2303 x(snapshot_trees, 15, 0, \ 2304 BIT_ULL(KEY_TYPE_snapshot_tree)) \ 2305 x(deleted_inodes, 16, BTREE_ID_SNAPSHOTS, \ 2306 BIT_ULL(KEY_TYPE_set)) \ 2307 x(logged_ops, 17, 0, \ 2308 BIT_ULL(KEY_TYPE_logged_op_truncate)| \ 2309 BIT_ULL(KEY_TYPE_logged_op_finsert)) 2310 2311 enum btree_id { 2312 #define x(name, nr, ...) BTREE_ID_##name = nr, 2313 BCH_BTREE_IDS() 2314 #undef x 2315 BTREE_ID_NR 2316 }; 2317 2318 #define BTREE_MAX_DEPTH 4U 2319 2320 /* Btree nodes */ 2321 2322 /* 2323 * Btree nodes 2324 * 2325 * On disk a btree node is a list/log of these; within each set the keys are 2326 * sorted 2327 */ 2328 struct bset { 2329 __le64 seq; 2330 2331 /* 2332 * Highest journal entry this bset contains keys for. 2333 * If on recovery we don't see that journal entry, this bset is ignored: 2334 * this allows us to preserve the order of all index updates after a 2335 * crash, since the journal records a total order of all index updates 2336 * and anything that didn't make it to the journal doesn't get used. 2337 */ 2338 __le64 journal_seq; 2339 2340 __le32 flags; 2341 __le16 version; 2342 __le16 u64s; /* count of d[] in u64s */ 2343 2344 struct bkey_packed start[0]; 2345 __u64 _data[]; 2346 } __packed __aligned(8); 2347 2348 LE32_BITMASK(BSET_CSUM_TYPE, struct bset, flags, 0, 4); 2349 2350 LE32_BITMASK(BSET_BIG_ENDIAN, struct bset, flags, 4, 5); 2351 LE32_BITMASK(BSET_SEPARATE_WHITEOUTS, 2352 struct bset, flags, 5, 6); 2353 2354 /* Sector offset within the btree node: */ 2355 LE32_BITMASK(BSET_OFFSET, struct bset, flags, 16, 32); 2356 2357 struct btree_node { 2358 struct bch_csum csum; 2359 __le64 magic; 2360 2361 /* this flags field is encrypted, unlike bset->flags: */ 2362 __le64 flags; 2363 2364 /* Closed interval: */ 2365 struct bpos min_key; 2366 struct bpos max_key; 2367 struct bch_extent_ptr _ptr; /* not used anymore */ 2368 struct bkey_format format; 2369 2370 union { 2371 struct bset keys; 2372 struct { 2373 __u8 pad[22]; 2374 __le16 u64s; 2375 __u64 _data[0]; 2376 2377 }; 2378 }; 2379 } __packed __aligned(8); 2380 2381 LE64_BITMASK(BTREE_NODE_ID_LO, struct btree_node, flags, 0, 4); 2382 LE64_BITMASK(BTREE_NODE_LEVEL, struct btree_node, flags, 4, 8); 2383 LE64_BITMASK(BTREE_NODE_NEW_EXTENT_OVERWRITE, 2384 struct btree_node, flags, 8, 9); 2385 LE64_BITMASK(BTREE_NODE_ID_HI, struct btree_node, flags, 9, 25); 2386 /* 25-32 unused */ 2387 LE64_BITMASK(BTREE_NODE_SEQ, struct btree_node, flags, 32, 64); 2388 2389 static inline __u64 BTREE_NODE_ID(struct btree_node *n) 2390 { 2391 return BTREE_NODE_ID_LO(n) | (BTREE_NODE_ID_HI(n) << 4); 2392 } 2393 2394 static inline void SET_BTREE_NODE_ID(struct btree_node *n, __u64 v) 2395 { 2396 SET_BTREE_NODE_ID_LO(n, v); 2397 SET_BTREE_NODE_ID_HI(n, v >> 4); 2398 } 2399 2400 struct btree_node_entry { 2401 struct bch_csum csum; 2402 2403 union { 2404 struct bset keys; 2405 struct { 2406 __u8 pad[22]; 2407 __le16 u64s; 2408 __u64 _data[0]; 2409 }; 2410 }; 2411 } __packed __aligned(8); 2412 2413 #endif /* _BCACHEFS_FORMAT_H */ 2414