1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _BCACHEFS_FORMAT_H
3 #define _BCACHEFS_FORMAT_H
6 * bcachefs on disk data structures
10 * There are three main types of on disk data structures in bcachefs (this is
11 * reduced from 5 in bcache)
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.
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
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.
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.
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.
42 * The journal also contains entry types for the btree roots, and blacklisted
43 * journal sequence numbers (see journal_seq_blacklist.c).
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
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
58 * BTREE KEYS (struct bkey):
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.
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).
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.
75 #include <asm/types.h>
76 #include <asm/byteorder.h>
77 #include <linux/kernel.h>
78 #include <linux/uuid.h>
80 #define LE_BITMASK(_bits, name, type, field, offset, end) \
81 static const unsigned name##_OFFSET = offset; \
82 static const unsigned name##_BITS = (end - offset); \
83 static const __u##_bits name##_MAX = (1ULL << (end - offset)) - 1; \
85 static inline __u64 name(const type *k) \
87 return (__le##_bits##_to_cpu(k->field) >> offset) & \
88 ~(~0ULL << (end - offset)); \
91 static inline void SET_##name(type *k, __u64 v) \
93 __u##_bits new = __le##_bits##_to_cpu(k->field); \
95 new &= ~(~(~0ULL << (end - offset)) << offset); \
96 new |= (v & ~(~0ULL << (end - offset))) << offset; \
97 k->field = __cpu_to_le##_bits(new); \
100 #define LE16_BITMASK(n, t, f, o, e) LE_BITMASK(16, n, t, f, o, e)
101 #define LE32_BITMASK(n, t, f, o, e) LE_BITMASK(32, n, t, f, o, e)
102 #define LE64_BITMASK(n, t, f, o, e) LE_BITMASK(64, n, t, f, o, e)
107 /* One unused slot for now: */
108 __u8 bits_per_field[6];
109 __le64 field_offset[6];
112 /* Btree keys - all units are in sectors */
116 * Word order matches machine byte order - btree code treats a bpos as a
117 * single large integer, for search/comparison purposes
119 * Note that wherever a bpos is embedded in another on disk data
120 * structure, it has to be byte swabbed when reading in metadata that
121 * wasn't written in native endian order:
123 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
127 #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
129 __u64 offset; /* Points to end of extent - sectors */
132 #error edit for your odd byteorder.
134 } __attribute__((packed, aligned(4)));
136 #define KEY_INODE_MAX ((__u64)~0ULL)
137 #define KEY_OFFSET_MAX ((__u64)~0ULL)
138 #define KEY_SNAPSHOT_MAX ((__u32)~0U)
139 #define KEY_SIZE_MAX ((__u32)~0U)
141 static inline struct bpos SPOS(__u64 inode, __u64 offset, __u32 snapshot)
143 return (struct bpos) {
146 .snapshot = snapshot,
150 #define POS_MIN SPOS(0, 0, 0)
151 #define POS_MAX SPOS(KEY_INODE_MAX, KEY_OFFSET_MAX, 0)
152 #define SPOS_MAX SPOS(KEY_INODE_MAX, KEY_OFFSET_MAX, KEY_SNAPSHOT_MAX)
153 #define POS(_inode, _offset) SPOS(_inode, _offset, 0)
155 /* Empty placeholder struct, for container_of() */
161 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
164 #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
168 } __attribute__((packed, aligned(4)));
171 /* Size of combined key and value, in u64s */
174 /* Format of key (0 for format local to btree node) */
175 #if defined(__LITTLE_ENDIAN_BITFIELD)
178 #elif defined (__BIG_ENDIAN_BITFIELD)
179 __u8 needs_whiteout:1,
182 #error edit for your odd byteorder.
185 /* Type of the value */
188 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
191 struct bversion version;
192 __u32 size; /* extent size, in sectors */
194 #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
196 __u32 size; /* extent size, in sectors */
197 struct bversion version;
201 } __attribute__((packed, aligned(8)));
206 /* Size of combined key and value, in u64s */
209 /* Format of key (0 for format local to btree node) */
212 * XXX: next incompat on disk format change, switch format and
213 * needs_whiteout - bkey_packed() will be cheaper if format is the high
214 * bits of the bitfield
216 #if defined(__LITTLE_ENDIAN_BITFIELD)
219 #elif defined (__BIG_ENDIAN_BITFIELD)
220 __u8 needs_whiteout:1,
224 /* Type of the value */
229 * We copy bkeys with struct assignment in various places, and while
230 * that shouldn't be done with packed bkeys we can't disallow it in C,
231 * and it's legal to cast a bkey to a bkey_packed - so padding it out
232 * to the same size as struct bkey should hopefully be safest.
234 __u8 pad[sizeof(struct bkey) - 3];
235 } __attribute__((packed, aligned(8)));
237 #define BKEY_U64s (sizeof(struct bkey) / sizeof(__u64))
238 #define BKEY_U64s_MAX U8_MAX
239 #define BKEY_VAL_U64s_MAX (BKEY_U64s_MAX - BKEY_U64s)
241 #define KEY_PACKED_BITS_START 24
243 #define KEY_FORMAT_LOCAL_BTREE 0
244 #define KEY_FORMAT_CURRENT 1
246 enum bch_bkey_fields {
251 BKEY_FIELD_VERSION_HI,
252 BKEY_FIELD_VERSION_LO,
256 #define bkey_format_field(name, field) \
257 [BKEY_FIELD_##name] = (sizeof(((struct bkey *) NULL)->field) * 8)
259 #define BKEY_FORMAT_CURRENT \
260 ((struct bkey_format) { \
261 .key_u64s = BKEY_U64s, \
262 .nr_fields = BKEY_NR_FIELDS, \
263 .bits_per_field = { \
264 bkey_format_field(INODE, p.inode), \
265 bkey_format_field(OFFSET, p.offset), \
266 bkey_format_field(SNAPSHOT, p.snapshot), \
267 bkey_format_field(SIZE, size), \
268 bkey_format_field(VERSION_HI, version.hi), \
269 bkey_format_field(VERSION_LO, version.lo), \
273 /* bkey with inline value */
279 /* Size of combined key and value, in u64s */
289 #define KEY(_inode, _offset, _size) \
292 .format = KEY_FORMAT_CURRENT, \
293 .p = POS(_inode, _offset), \
297 static inline void bkey_init(struct bkey *k)
302 #define bkey_bytes(_k) ((_k)->u64s * sizeof(__u64))
304 #define __BKEY_PADDED(key, pad) \
305 struct { struct bkey_i key; __u64 key ## _pad[pad]; }
308 * - DELETED keys are used internally to mark keys that should be ignored but
309 * override keys in composition order. Their version number is ignored.
311 * - DISCARDED keys indicate that the data is all 0s because it has been
312 * discarded. DISCARDs may have a version; if the version is nonzero the key
313 * will be persistent, otherwise the key will be dropped whenever the btree
314 * node is rewritten (like DELETED keys).
316 * - ERROR: any read of the data returns a read error, as the data was lost due
317 * to a failing device. Like DISCARDED keys, they can be removed (overridden)
318 * by new writes or cluster-wide GC. Node repair can also overwrite them with
319 * the same or a more recent version number, but not with an older version
322 * - WHITEOUT: for hash table btrees
324 #define BCH_BKEY_TYPES() \
329 x(hash_whiteout, 4) \
334 x(inode_generation, 9) \
343 x(btree_ptr_v2, 18) \
344 x(indirect_inline_data, 19) \
350 #define x(name, nr) KEY_TYPE_##name = nr,
360 struct bch_whiteout {
373 struct bch_hash_whiteout {
380 * In extent bkeys, the value is a list of pointers (bch_extent_ptr), optionally
381 * preceded by checksum/compression information (bch_extent_crc32 or
384 * One major determining factor in the format of extents is how we handle and
385 * represent extents that have been partially overwritten and thus trimmed:
387 * If an extent is not checksummed or compressed, when the extent is trimmed we
388 * don't have to remember the extent we originally allocated and wrote: we can
389 * merely adjust ptr->offset to point to the start of the data that is currently
390 * live. The size field in struct bkey records the current (live) size of the
391 * extent, and is also used to mean "size of region on disk that we point to" in
394 * Thus an extent that is not checksummed or compressed will consist only of a
395 * list of bch_extent_ptrs, with none of the fields in
396 * bch_extent_crc32/bch_extent_crc64.
398 * When an extent is checksummed or compressed, it's not possible to read only
399 * the data that is currently live: we have to read the entire extent that was
400 * originally written, and then return only the part of the extent that is
403 * Thus, in addition to the current size of the extent in struct bkey, we need
404 * to store the size of the originally allocated space - this is the
405 * compressed_size and uncompressed_size fields in bch_extent_crc32/64. Also,
406 * when the extent is trimmed, instead of modifying the offset field of the
407 * pointer, we keep a second smaller offset field - "offset into the original
408 * extent of the currently live region".
410 * The other major determining factor is replication and data migration:
412 * Each pointer may have its own bch_extent_crc32/64. When doing a replicated
413 * write, we will initially write all the replicas in the same format, with the
414 * same checksum type and compression format - however, when copygc runs later (or
415 * tiering/cache promotion, anything that moves data), it is not in general
416 * going to rewrite all the pointers at once - one of the replicas may be in a
417 * bucket on one device that has very little fragmentation while another lives
418 * in a bucket that has become heavily fragmented, and thus is being rewritten
419 * sooner than the rest.
421 * Thus it will only move a subset of the pointers (or in the case of
422 * tiering/cache promotion perhaps add a single pointer without dropping any
423 * current pointers), and if the extent has been partially overwritten it must
424 * write only the currently live portion (or copygc would not be able to reduce
425 * fragmentation!) - which necessitates a different bch_extent_crc format for
428 * But in the interests of space efficiency, we don't want to store one
429 * bch_extent_crc for each pointer if we don't have to.
431 * Thus, a bch_extent consists of bch_extent_crc32s, bch_extent_crc64s, and
432 * bch_extent_ptrs appended arbitrarily one after the other. We determine the
433 * type of a given entry with a scheme similar to utf8 (except we're encoding a
434 * type, not a size), encoding the type in the position of the first set bit:
436 * bch_extent_crc32 - 0b1
437 * bch_extent_ptr - 0b10
438 * bch_extent_crc64 - 0b100
440 * We do it this way because bch_extent_crc32 is _very_ constrained on bits (and
441 * bch_extent_crc64 is the least constrained).
443 * Then, each bch_extent_crc32/64 applies to the pointers that follow after it,
444 * until the next bch_extent_crc32/64.
446 * If there are no bch_extent_crcs preceding a bch_extent_ptr, then that pointer
447 * is neither checksummed nor compressed.
450 /* 128 bits, sufficient for cryptographic MACs: */
454 } __attribute__((packed, aligned(8)));
456 #define BCH_EXTENT_ENTRY_TYPES() \
462 #define BCH_EXTENT_ENTRY_MAX 5
464 enum bch_extent_entry_type {
465 #define x(f, n) BCH_EXTENT_ENTRY_##f = n,
466 BCH_EXTENT_ENTRY_TYPES()
470 /* Compressed/uncompressed size are stored biased by 1: */
471 struct bch_extent_crc32 {
472 #if defined(__LITTLE_ENDIAN_BITFIELD)
475 _uncompressed_size:7,
481 #elif defined (__BIG_ENDIAN_BITFIELD)
483 __u32 compression_type:4,
487 _uncompressed_size:7,
491 } __attribute__((packed, aligned(8)));
493 #define CRC32_SIZE_MAX (1U << 7)
494 #define CRC32_NONCE_MAX 0
496 struct bch_extent_crc64 {
497 #if defined(__LITTLE_ENDIAN_BITFIELD)
500 _uncompressed_size:9,
506 #elif defined (__BIG_ENDIAN_BITFIELD)
512 _uncompressed_size:9,
517 } __attribute__((packed, aligned(8)));
519 #define CRC64_SIZE_MAX (1U << 9)
520 #define CRC64_NONCE_MAX ((1U << 10) - 1)
522 struct bch_extent_crc128 {
523 #if defined(__LITTLE_ENDIAN_BITFIELD)
526 _uncompressed_size:13,
531 #elif defined (__BIG_ENDIAN_BITFIELD)
532 __u64 compression_type:4,
536 _uncompressed_size:13,
540 struct bch_csum csum;
541 } __attribute__((packed, aligned(8)));
543 #define CRC128_SIZE_MAX (1U << 13)
544 #define CRC128_NONCE_MAX ((1U << 13) - 1)
547 * @reservation - pointer hasn't been written to, just reserved
549 struct bch_extent_ptr {
550 #if defined(__LITTLE_ENDIAN_BITFIELD)
555 offset:44, /* 8 petabytes */
558 #elif defined (__BIG_ENDIAN_BITFIELD)
567 } __attribute__((packed, aligned(8)));
569 struct bch_extent_stripe_ptr {
570 #if defined(__LITTLE_ENDIAN_BITFIELD)
575 #elif defined (__BIG_ENDIAN_BITFIELD)
583 struct bch_extent_reservation {
584 #if defined(__LITTLE_ENDIAN_BITFIELD)
589 #elif defined (__BIG_ENDIAN_BITFIELD)
597 union bch_extent_entry {
598 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ || __BITS_PER_LONG == 64
600 #elif __BITS_PER_LONG == 32
606 #error edit for your odd byteorder.
609 #define x(f, n) struct bch_extent_##f f;
610 BCH_EXTENT_ENTRY_TYPES()
614 struct bch_btree_ptr {
617 struct bch_extent_ptr start[0];
619 } __attribute__((packed, aligned(8)));
621 struct bch_btree_ptr_v2 {
626 __le16 sectors_written;
629 struct bch_extent_ptr start[0];
631 } __attribute__((packed, aligned(8)));
633 LE16_BITMASK(BTREE_PTR_RANGE_UPDATED, struct bch_btree_ptr_v2, flags, 0, 1);
638 union bch_extent_entry start[0];
640 } __attribute__((packed, aligned(8)));
642 struct bch_reservation {
648 } __attribute__((packed, aligned(8)));
650 /* Maximum size (in u64s) a single pointer could be: */
651 #define BKEY_EXTENT_PTR_U64s_MAX\
652 ((sizeof(struct bch_extent_crc128) + \
653 sizeof(struct bch_extent_ptr)) / sizeof(u64))
655 /* Maximum possible size of an entire extent value: */
656 #define BKEY_EXTENT_VAL_U64s_MAX \
657 (1 + BKEY_EXTENT_PTR_U64s_MAX * (BCH_REPLICAS_MAX + 1))
659 /* * Maximum possible size of an entire extent, key + value: */
660 #define BKEY_EXTENT_U64s_MAX (BKEY_U64s + BKEY_EXTENT_VAL_U64s_MAX)
662 /* Btree pointers don't carry around checksums: */
663 #define BKEY_BTREE_PTR_VAL_U64s_MAX \
664 ((sizeof(struct bch_btree_ptr_v2) + \
665 sizeof(struct bch_extent_ptr) * BCH_REPLICAS_MAX) / sizeof(u64))
666 #define BKEY_BTREE_PTR_U64s_MAX \
667 (BKEY_U64s + BKEY_BTREE_PTR_VAL_U64s_MAX)
671 #define BLOCKDEV_INODE_MAX 4096
673 #define BCACHEFS_ROOT_INO 4096
682 } __attribute__((packed, aligned(8)));
684 struct bch_inode_generation {
687 __le32 bi_generation;
689 } __attribute__((packed, aligned(8)));
692 * bi_subvol and bi_parent_subvol are only set for subvolume roots:
695 #define BCH_INODE_FIELDS() \
705 x(bi_generation, 32) \
707 x(bi_data_checksum, 8) \
708 x(bi_compression, 8) \
710 x(bi_background_compression, 8) \
711 x(bi_data_replicas, 8) \
712 x(bi_promote_target, 16) \
713 x(bi_foreground_target, 16) \
714 x(bi_background_target, 16) \
715 x(bi_erasure_code, 16) \
716 x(bi_fields_set, 16) \
718 x(bi_dir_offset, 64) \
720 x(bi_parent_subvol, 32)
722 /* subset of BCH_INODE_FIELDS */
723 #define BCH_INODE_OPTS() \
724 x(data_checksum, 8) \
727 x(background_compression, 8) \
728 x(data_replicas, 8) \
729 x(promote_target, 16) \
730 x(foreground_target, 16) \
731 x(background_target, 16) \
735 #define x(name, ...) \
744 * User flags (get/settable with FS_IOC_*FLAGS, correspond to FS_*_FL
747 __BCH_INODE_SYNC = 0,
748 __BCH_INODE_IMMUTABLE = 1,
749 __BCH_INODE_APPEND = 2,
750 __BCH_INODE_NODUMP = 3,
751 __BCH_INODE_NOATIME = 4,
753 __BCH_INODE_I_SIZE_DIRTY= 5,
754 __BCH_INODE_I_SECTORS_DIRTY= 6,
755 __BCH_INODE_UNLINKED = 7,
756 __BCH_INODE_BACKPTR_UNTRUSTED = 8,
758 /* bits 20+ reserved for packed fields below: */
761 #define BCH_INODE_SYNC (1 << __BCH_INODE_SYNC)
762 #define BCH_INODE_IMMUTABLE (1 << __BCH_INODE_IMMUTABLE)
763 #define BCH_INODE_APPEND (1 << __BCH_INODE_APPEND)
764 #define BCH_INODE_NODUMP (1 << __BCH_INODE_NODUMP)
765 #define BCH_INODE_NOATIME (1 << __BCH_INODE_NOATIME)
766 #define BCH_INODE_I_SIZE_DIRTY (1 << __BCH_INODE_I_SIZE_DIRTY)
767 #define BCH_INODE_I_SECTORS_DIRTY (1 << __BCH_INODE_I_SECTORS_DIRTY)
768 #define BCH_INODE_UNLINKED (1 << __BCH_INODE_UNLINKED)
769 #define BCH_INODE_BACKPTR_UNTRUSTED (1 << __BCH_INODE_BACKPTR_UNTRUSTED)
771 LE32_BITMASK(INODE_STR_HASH, struct bch_inode, bi_flags, 20, 24);
772 LE32_BITMASK(INODE_NR_FIELDS, struct bch_inode, bi_flags, 24, 31);
773 LE32_BITMASK(INODE_NEW_VARINT, struct bch_inode, bi_flags, 31, 32);
778 * Dirents (and xattrs) have to implement string lookups; since our b-tree
779 * doesn't support arbitrary length strings for the key, we instead index by a
780 * 64 bit hash (currently truncated sha1) of the string, stored in the offset
781 * field of the key - using linear probing to resolve hash collisions. This also
782 * provides us with the readdir cookie posix requires.
784 * Linear probing requires us to use whiteouts for deletions, in the event of a
791 /* Target inode number: */
794 struct { /* DT_SUBVOL */
795 __le32 d_child_subvol;
796 __le32 d_parent_subvol;
801 * Copy of mode bits 12-15 from the target inode - so userspace can get
802 * the filetype without having to do a stat()
807 } __attribute__((packed, aligned(8)));
810 #define BCH_DT_MAX 17
812 #define BCH_NAME_MAX (U8_MAX * sizeof(u64) - \
813 sizeof(struct bkey) - \
814 offsetof(struct bch_dirent, d_name))
819 #define KEY_TYPE_XATTR_INDEX_USER 0
820 #define KEY_TYPE_XATTR_INDEX_POSIX_ACL_ACCESS 1
821 #define KEY_TYPE_XATTR_INDEX_POSIX_ACL_DEFAULT 2
822 #define KEY_TYPE_XATTR_INDEX_TRUSTED 3
823 #define KEY_TYPE_XATTR_INDEX_SECURITY 4
831 } __attribute__((packed, aligned(8)));
833 /* Bucket/allocation information: */
840 } __attribute__((packed, aligned(8)));
842 #define BCH_ALLOC_FIELDS_V1() \
846 x(dirty_sectors, 16) \
847 x(cached_sectors, 16) \
850 x(stripe_redundancy, 8)
852 struct bch_alloc_v2 {
859 } __attribute__((packed, aligned(8)));
861 #define BCH_ALLOC_FIELDS_V2() \
864 x(dirty_sectors, 16) \
865 x(cached_sectors, 16) \
867 x(stripe_redundancy, 8)
870 #define x(name, _bits) BCH_ALLOC_FIELD_V1_##name,
871 BCH_ALLOC_FIELDS_V1()
885 enum quota_counters {
891 struct bch_quota_counter {
898 struct bch_quota_counter c[Q_COUNTERS];
899 } __attribute__((packed, aligned(8)));
910 __u8 csum_granularity_bits;
914 struct bch_extent_ptr ptrs[0];
915 } __attribute__((packed, aligned(8)));
919 struct bch_reflink_p {
923 * A reflink pointer might point to an indirect extent which is then
924 * later split (by copygc or rebalance). If we only pointed to part of
925 * the original indirect extent, and then one of the fragments is
926 * outside the range we point to, we'd leak a refcount: so when creating
927 * reflink pointers, we need to store pad values to remember the full
928 * range we were taking a reference on.
932 } __attribute__((packed, aligned(8)));
934 struct bch_reflink_v {
937 union bch_extent_entry start[0];
939 } __attribute__((packed, aligned(8)));
941 struct bch_indirect_inline_data {
949 struct bch_inline_data {
956 #define SUBVOL_POS_MIN POS(0, 1)
957 #define SUBVOL_POS_MAX POS(0, S32_MAX)
958 #define BCACHEFS_ROOT_SUBVOL 1
960 struct bch_subvolume {
967 LE32_BITMASK(BCH_SUBVOLUME_RO, struct bch_subvolume, flags, 0, 1)
969 * We need to know whether a subvolume is a snapshot so we can know whether we
970 * can delete it (or whether it should just be rm -rf'd)
972 LE32_BITMASK(BCH_SUBVOLUME_SNAP, struct bch_subvolume, flags, 1, 2)
976 struct bch_snapshot {
985 LE32_BITMASK(BCH_SNAPSHOT_DELETED, struct bch_snapshot, flags, 0, 1)
987 /* True if a subvolume points to this snapshot node: */
988 LE32_BITMASK(BCH_SNAPSHOT_SUBVOL, struct bch_snapshot, flags, 1, 2)
990 /* Optional/variable size superblock sections: */
992 struct bch_sb_field {
998 #define BCH_SB_FIELDS() \
1007 x(journal_seq_blacklist, 8)
1009 enum bch_sb_field_type {
1010 #define x(f, nr) BCH_SB_FIELD_##f = nr,
1016 /* BCH_SB_FIELD_journal: */
1018 struct bch_sb_field_journal {
1019 struct bch_sb_field field;
1023 /* BCH_SB_FIELD_members: */
1025 #define BCH_MIN_NR_NBUCKETS (1 << 6)
1029 __le64 nbuckets; /* device size */
1030 __le16 first_bucket; /* index of first bucket used */
1031 __le16 bucket_size; /* sectors */
1033 __le64 last_mount; /* time_t */
1038 LE64_BITMASK(BCH_MEMBER_STATE, struct bch_member, flags[0], 0, 4)
1039 /* 4-10 unused, was TIER, HAS_(META)DATA */
1040 LE64_BITMASK(BCH_MEMBER_REPLACEMENT, struct bch_member, flags[0], 10, 14)
1041 LE64_BITMASK(BCH_MEMBER_DISCARD, struct bch_member, flags[0], 14, 15)
1042 LE64_BITMASK(BCH_MEMBER_DATA_ALLOWED, struct bch_member, flags[0], 15, 20)
1043 LE64_BITMASK(BCH_MEMBER_GROUP, struct bch_member, flags[0], 20, 28)
1044 LE64_BITMASK(BCH_MEMBER_DURABILITY, struct bch_member, flags[0], 28, 30)
1047 LE64_BITMASK(BCH_MEMBER_NR_READ_ERRORS, struct bch_member, flags[1], 0, 20);
1048 LE64_BITMASK(BCH_MEMBER_NR_WRITE_ERRORS,struct bch_member, flags[1], 20, 40);
1051 #define BCH_MEMBER_STATES() \
1057 enum bch_member_state {
1058 #define x(t, n) BCH_MEMBER_STATE_##t = n,
1064 #define BCH_CACHE_REPLACEMENT_POLICIES() \
1069 enum bch_cache_replacement_policies {
1070 #define x(t, n) BCH_CACHE_REPLACEMENT_##t = n,
1071 BCH_CACHE_REPLACEMENT_POLICIES()
1073 BCH_CACHE_REPLACEMENT_NR
1076 struct bch_sb_field_members {
1077 struct bch_sb_field field;
1078 struct bch_member members[0];
1081 /* BCH_SB_FIELD_crypt: */
1091 #define BCH_KEY_MAGIC \
1092 (((u64) 'b' << 0)|((u64) 'c' << 8)| \
1093 ((u64) 'h' << 16)|((u64) '*' << 24)| \
1094 ((u64) '*' << 32)|((u64) 'k' << 40)| \
1095 ((u64) 'e' << 48)|((u64) 'y' << 56))
1097 struct bch_encrypted_key {
1103 * If this field is present in the superblock, it stores an encryption key which
1104 * is used encrypt all other data/metadata. The key will normally be encrypted
1105 * with the key userspace provides, but if encryption has been turned off we'll
1106 * just store the master key unencrypted in the superblock so we can access the
1107 * previously encrypted data.
1109 struct bch_sb_field_crypt {
1110 struct bch_sb_field field;
1114 struct bch_encrypted_key key;
1117 LE64_BITMASK(BCH_CRYPT_KDF_TYPE, struct bch_sb_field_crypt, flags, 0, 4);
1119 enum bch_kdf_types {
1124 /* stored as base 2 log of scrypt params: */
1125 LE64_BITMASK(BCH_KDF_SCRYPT_N, struct bch_sb_field_crypt, kdf_flags, 0, 16);
1126 LE64_BITMASK(BCH_KDF_SCRYPT_R, struct bch_sb_field_crypt, kdf_flags, 16, 32);
1127 LE64_BITMASK(BCH_KDF_SCRYPT_P, struct bch_sb_field_crypt, kdf_flags, 32, 48);
1129 /* BCH_SB_FIELD_replicas: */
1131 #define BCH_DATA_TYPES() \
1140 enum bch_data_type {
1141 #define x(t, n) BCH_DATA_##t,
1147 struct bch_replicas_entry_v0 {
1151 } __attribute__((packed));
1153 struct bch_sb_field_replicas_v0 {
1154 struct bch_sb_field field;
1155 struct bch_replicas_entry_v0 entries[0];
1156 } __attribute__((packed, aligned(8)));
1158 struct bch_replicas_entry {
1163 } __attribute__((packed));
1165 #define replicas_entry_bytes(_i) \
1166 (offsetof(typeof(*(_i)), devs) + (_i)->nr_devs)
1168 struct bch_sb_field_replicas {
1169 struct bch_sb_field field;
1170 struct bch_replicas_entry entries[0];
1171 } __attribute__((packed, aligned(8)));
1173 /* BCH_SB_FIELD_quota: */
1175 struct bch_sb_quota_counter {
1180 struct bch_sb_quota_type {
1182 struct bch_sb_quota_counter c[Q_COUNTERS];
1185 struct bch_sb_field_quota {
1186 struct bch_sb_field field;
1187 struct bch_sb_quota_type q[QTYP_NR];
1188 } __attribute__((packed, aligned(8)));
1190 /* BCH_SB_FIELD_disk_groups: */
1192 #define BCH_SB_LABEL_SIZE 32
1194 struct bch_disk_group {
1195 __u8 label[BCH_SB_LABEL_SIZE];
1197 } __attribute__((packed, aligned(8)));
1199 LE64_BITMASK(BCH_GROUP_DELETED, struct bch_disk_group, flags[0], 0, 1)
1200 LE64_BITMASK(BCH_GROUP_DATA_ALLOWED, struct bch_disk_group, flags[0], 1, 6)
1201 LE64_BITMASK(BCH_GROUP_PARENT, struct bch_disk_group, flags[0], 6, 24)
1203 struct bch_sb_field_disk_groups {
1204 struct bch_sb_field field;
1205 struct bch_disk_group entries[0];
1206 } __attribute__((packed, aligned(8)));
1209 * On clean shutdown, store btree roots and current journal sequence number in
1216 __u8 type; /* designates what this jset holds */
1220 struct bkey_i start[0];
1225 struct bch_sb_field_clean {
1226 struct bch_sb_field field;
1229 __le16 _read_clock; /* no longer used */
1230 __le16 _write_clock;
1234 struct jset_entry start[0];
1239 struct journal_seq_blacklist_entry {
1244 struct bch_sb_field_journal_seq_blacklist {
1245 struct bch_sb_field field;
1248 struct journal_seq_blacklist_entry start[0];
1256 * New versioning scheme:
1257 * One common version number for all on disk data structures - superblock, btree
1258 * nodes, journal entries
1260 #define BCH_JSET_VERSION_OLD 2
1261 #define BCH_BSET_VERSION_OLD 3
1263 enum bcachefs_metadata_version {
1264 bcachefs_metadata_version_min = 9,
1265 bcachefs_metadata_version_new_versioning = 10,
1266 bcachefs_metadata_version_bkey_renumber = 10,
1267 bcachefs_metadata_version_inode_btree_change = 11,
1268 bcachefs_metadata_version_snapshot = 12,
1269 bcachefs_metadata_version_inode_backpointers = 13,
1270 bcachefs_metadata_version_btree_ptr_sectors_written = 14,
1271 bcachefs_metadata_version_snapshot_2 = 15,
1272 bcachefs_metadata_version_reflink_p_fix = 16,
1273 bcachefs_metadata_version_subvol_dirent = 17,
1274 bcachefs_metadata_version_max = 18,
1277 #define bcachefs_metadata_version_current (bcachefs_metadata_version_max - 1)
1279 #define BCH_SB_SECTOR 8
1280 #define BCH_SB_MEMBERS_MAX 64 /* XXX kill */
1282 struct bch_sb_layout {
1283 uuid_le magic; /* bcachefs superblock UUID */
1285 __u8 sb_max_size_bits; /* base 2 of 512 byte sectors */
1286 __u8 nr_superblocks;
1288 __le64 sb_offset[61];
1289 } __attribute__((packed, aligned(8)));
1291 #define BCH_SB_LAYOUT_SECTOR 7
1294 * @offset - sector where this sb was written
1295 * @version - on disk format version
1296 * @version_min - Oldest metadata version this filesystem contains; so we can
1297 * safely drop compatibility code and refuse to mount filesystems
1299 * @magic - identifies as a bcachefs superblock (BCACHE_MAGIC)
1300 * @seq - incremented each time superblock is written
1301 * @uuid - used for generating various magic numbers and identifying
1302 * member devices, never changes
1303 * @user_uuid - user visible UUID, may be changed
1304 * @label - filesystem label
1305 * @seq - identifies most recent superblock, incremented each time
1306 * superblock is written
1307 * @features - enabled incompatible features
1310 struct bch_csum csum;
1317 __u8 label[BCH_SB_LABEL_SIZE];
1326 __le64 time_base_lo;
1327 __le32 time_base_hi;
1328 __le32 time_precision;
1334 struct bch_sb_layout layout;
1337 struct bch_sb_field start[0];
1340 } __attribute__((packed, aligned(8)));
1344 * BCH_SB_INITALIZED - set on first mount
1345 * BCH_SB_CLEAN - did we shut down cleanly? Just a hint, doesn't affect
1346 * behaviour of mount/recovery path:
1347 * BCH_SB_INODE_32BIT - limit inode numbers to 32 bits
1348 * BCH_SB_128_BIT_MACS - 128 bit macs instead of 80
1349 * BCH_SB_ENCRYPTION_TYPE - if nonzero encryption is enabled; overrides
1350 * DATA/META_CSUM_TYPE. Also indicates encryption
1351 * algorithm in use, if/when we get more than one
1354 LE16_BITMASK(BCH_SB_BLOCK_SIZE, struct bch_sb, block_size, 0, 16);
1356 LE64_BITMASK(BCH_SB_INITIALIZED, struct bch_sb, flags[0], 0, 1);
1357 LE64_BITMASK(BCH_SB_CLEAN, struct bch_sb, flags[0], 1, 2);
1358 LE64_BITMASK(BCH_SB_CSUM_TYPE, struct bch_sb, flags[0], 2, 8);
1359 LE64_BITMASK(BCH_SB_ERROR_ACTION, struct bch_sb, flags[0], 8, 12);
1361 LE64_BITMASK(BCH_SB_BTREE_NODE_SIZE, struct bch_sb, flags[0], 12, 28);
1363 LE64_BITMASK(BCH_SB_GC_RESERVE, struct bch_sb, flags[0], 28, 33);
1364 LE64_BITMASK(BCH_SB_ROOT_RESERVE, struct bch_sb, flags[0], 33, 40);
1366 LE64_BITMASK(BCH_SB_META_CSUM_TYPE, struct bch_sb, flags[0], 40, 44);
1367 LE64_BITMASK(BCH_SB_DATA_CSUM_TYPE, struct bch_sb, flags[0], 44, 48);
1369 LE64_BITMASK(BCH_SB_META_REPLICAS_WANT, struct bch_sb, flags[0], 48, 52);
1370 LE64_BITMASK(BCH_SB_DATA_REPLICAS_WANT, struct bch_sb, flags[0], 52, 56);
1372 LE64_BITMASK(BCH_SB_POSIX_ACL, struct bch_sb, flags[0], 56, 57);
1373 LE64_BITMASK(BCH_SB_USRQUOTA, struct bch_sb, flags[0], 57, 58);
1374 LE64_BITMASK(BCH_SB_GRPQUOTA, struct bch_sb, flags[0], 58, 59);
1375 LE64_BITMASK(BCH_SB_PRJQUOTA, struct bch_sb, flags[0], 59, 60);
1377 LE64_BITMASK(BCH_SB_HAS_ERRORS, struct bch_sb, flags[0], 60, 61);
1378 LE64_BITMASK(BCH_SB_HAS_TOPOLOGY_ERRORS,struct bch_sb, flags[0], 61, 62);
1380 LE64_BITMASK(BCH_SB_BIG_ENDIAN, struct bch_sb, flags[0], 62, 63);
1382 LE64_BITMASK(BCH_SB_STR_HASH_TYPE, struct bch_sb, flags[1], 0, 4);
1383 LE64_BITMASK(BCH_SB_COMPRESSION_TYPE, struct bch_sb, flags[1], 4, 8);
1384 LE64_BITMASK(BCH_SB_INODE_32BIT, struct bch_sb, flags[1], 8, 9);
1386 LE64_BITMASK(BCH_SB_128_BIT_MACS, struct bch_sb, flags[1], 9, 10);
1387 LE64_BITMASK(BCH_SB_ENCRYPTION_TYPE, struct bch_sb, flags[1], 10, 14);
1390 * Max size of an extent that may require bouncing to read or write
1391 * (checksummed, compressed): 64k
1393 LE64_BITMASK(BCH_SB_ENCODED_EXTENT_MAX_BITS,
1394 struct bch_sb, flags[1], 14, 20);
1396 LE64_BITMASK(BCH_SB_META_REPLICAS_REQ, struct bch_sb, flags[1], 20, 24);
1397 LE64_BITMASK(BCH_SB_DATA_REPLICAS_REQ, struct bch_sb, flags[1], 24, 28);
1399 LE64_BITMASK(BCH_SB_PROMOTE_TARGET, struct bch_sb, flags[1], 28, 40);
1400 LE64_BITMASK(BCH_SB_FOREGROUND_TARGET, struct bch_sb, flags[1], 40, 52);
1401 LE64_BITMASK(BCH_SB_BACKGROUND_TARGET, struct bch_sb, flags[1], 52, 64);
1403 LE64_BITMASK(BCH_SB_BACKGROUND_COMPRESSION_TYPE,
1404 struct bch_sb, flags[2], 0, 4);
1405 LE64_BITMASK(BCH_SB_GC_RESERVE_BYTES, struct bch_sb, flags[2], 4, 64);
1407 LE64_BITMASK(BCH_SB_ERASURE_CODE, struct bch_sb, flags[3], 0, 16);
1408 LE64_BITMASK(BCH_SB_METADATA_TARGET, struct bch_sb, flags[3], 16, 28);
1409 LE64_BITMASK(BCH_SB_SHARD_INUMS, struct bch_sb, flags[3], 28, 29);
1410 LE64_BITMASK(BCH_SB_INODES_USE_KEY_CACHE,struct bch_sb, flags[3], 29, 30);
1415 * journal_seq_blacklist_v3: gates BCH_SB_FIELD_journal_seq_blacklist
1416 * reflink: gates KEY_TYPE_reflink
1417 * inline_data: gates KEY_TYPE_inline_data
1418 * new_siphash: gates BCH_STR_HASH_SIPHASH
1419 * new_extent_overwrite: gates BTREE_NODE_NEW_EXTENT_OVERWRITE
1421 #define BCH_SB_FEATURES() \
1425 x(atomic_nlink, 3) \
1427 x(journal_seq_blacklist_v3, 5) \
1431 x(new_extent_overwrite, 9) \
1432 x(incompressible, 10) \
1433 x(btree_ptr_v2, 11) \
1434 x(extents_above_btree_updates, 12) \
1435 x(btree_updates_journalled, 13) \
1436 x(reflink_inline_data, 14) \
1438 x(journal_no_flush, 16) \
1440 x(extents_across_btree_nodes, 18)
1442 #define BCH_SB_FEATURES_ALWAYS \
1443 ((1ULL << BCH_FEATURE_new_extent_overwrite)| \
1444 (1ULL << BCH_FEATURE_extents_above_btree_updates)|\
1445 (1ULL << BCH_FEATURE_btree_updates_journalled)|\
1446 (1ULL << BCH_FEATURE_alloc_v2)|\
1447 (1ULL << BCH_FEATURE_extents_across_btree_nodes))
1449 #define BCH_SB_FEATURES_ALL \
1450 (BCH_SB_FEATURES_ALWAYS| \
1451 (1ULL << BCH_FEATURE_new_siphash)| \
1452 (1ULL << BCH_FEATURE_btree_ptr_v2)| \
1453 (1ULL << BCH_FEATURE_new_varint)| \
1454 (1ULL << BCH_FEATURE_journal_no_flush))
1456 enum bch_sb_feature {
1457 #define x(f, n) BCH_FEATURE_##f,
1463 #define BCH_SB_COMPAT() \
1465 x(alloc_metadata, 1) \
1466 x(extents_above_btree_updates_done, 2) \
1467 x(bformat_overflow_done, 3)
1469 enum bch_sb_compat {
1470 #define x(f, n) BCH_COMPAT_##f,
1478 #define BCH_REPLICAS_MAX 4U
1480 #define BCH_BKEY_PTRS_MAX 16U
1482 #define BCH_ERROR_ACTIONS() \
1487 enum bch_error_actions {
1488 #define x(t, n) BCH_ON_ERROR_##t = n,
1494 enum bch_str_hash_type {
1495 BCH_STR_HASH_CRC32C = 0,
1496 BCH_STR_HASH_CRC64 = 1,
1497 BCH_STR_HASH_SIPHASH_OLD = 2,
1498 BCH_STR_HASH_SIPHASH = 3,
1499 BCH_STR_HASH_NR = 4,
1502 #define BCH_STR_HASH_OPTS() \
1507 enum bch_str_hash_opts {
1508 #define x(t, n) BCH_STR_HASH_OPT_##t = n,
1514 enum bch_csum_type {
1516 BCH_CSUM_CRC32C_NONZERO = 1,
1517 BCH_CSUM_CRC64_NONZERO = 2,
1518 BCH_CSUM_CHACHA20_POLY1305_80 = 3,
1519 BCH_CSUM_CHACHA20_POLY1305_128 = 4,
1520 BCH_CSUM_CRC32C = 5,
1522 BCH_CSUM_XXHASH = 7,
1526 static const unsigned bch_crc_bytes[] = {
1527 [BCH_CSUM_NONE] = 0,
1528 [BCH_CSUM_CRC32C_NONZERO] = 4,
1529 [BCH_CSUM_CRC32C] = 4,
1530 [BCH_CSUM_CRC64_NONZERO] = 8,
1531 [BCH_CSUM_CRC64] = 8,
1532 [BCH_CSUM_XXHASH] = 8,
1533 [BCH_CSUM_CHACHA20_POLY1305_80] = 10,
1534 [BCH_CSUM_CHACHA20_POLY1305_128] = 16,
1537 static inline _Bool bch2_csum_type_is_encryption(enum bch_csum_type type)
1540 case BCH_CSUM_CHACHA20_POLY1305_80:
1541 case BCH_CSUM_CHACHA20_POLY1305_128:
1548 #define BCH_CSUM_OPTS() \
1554 enum bch_csum_opts {
1555 #define x(t, n) BCH_CSUM_OPT_##t = n,
1561 #define BCH_COMPRESSION_TYPES() \
1567 x(incompressible, 5)
1569 enum bch_compression_type {
1570 #define x(t, n) BCH_COMPRESSION_TYPE_##t = n,
1571 BCH_COMPRESSION_TYPES()
1573 BCH_COMPRESSION_TYPE_NR
1576 #define BCH_COMPRESSION_OPTS() \
1582 enum bch_compression_opts {
1583 #define x(t, n) BCH_COMPRESSION_OPT_##t = n,
1584 BCH_COMPRESSION_OPTS()
1586 BCH_COMPRESSION_OPT_NR
1592 * The various other data structures have their own magic numbers, which are
1593 * xored with the first part of the cache set's UUID
1596 #define BCACHE_MAGIC \
1597 UUID_LE(0xf67385c6, 0x1a4e, 0xca45, \
1598 0x82, 0x65, 0xf5, 0x7f, 0x48, 0xba, 0x6d, 0x81)
1600 #define BCACHEFS_STATFS_MAGIC 0xca451a4e
1602 #define JSET_MAGIC __cpu_to_le64(0x245235c1a3625032ULL)
1603 #define BSET_MAGIC __cpu_to_le64(0x90135c78b99e07f5ULL)
1605 static inline __le64 __bch2_sb_magic(struct bch_sb *sb)
1608 memcpy(&ret, &sb->uuid, sizeof(ret));
1612 static inline __u64 __jset_magic(struct bch_sb *sb)
1614 return __le64_to_cpu(__bch2_sb_magic(sb) ^ JSET_MAGIC);
1617 static inline __u64 __bset_magic(struct bch_sb *sb)
1619 return __le64_to_cpu(__bch2_sb_magic(sb) ^ BSET_MAGIC);
1624 #define JSET_KEYS_U64s (sizeof(struct jset_entry) / sizeof(__u64))
1626 #define BCH_JSET_ENTRY_TYPES() \
1631 x(blacklist_v2, 4) \
1638 #define x(f, nr) BCH_JSET_ENTRY_##f = nr,
1639 BCH_JSET_ENTRY_TYPES()
1645 * Journal sequence numbers can be blacklisted: bsets record the max sequence
1646 * number of all the journal entries they contain updates for, so that on
1647 * recovery we can ignore those bsets that contain index updates newer that what
1648 * made it into the journal.
1650 * This means that we can't reuse that journal_seq - we have to skip it, and
1651 * then record that we skipped it so that the next time we crash and recover we
1652 * don't think there was a missing journal entry.
1654 struct jset_entry_blacklist {
1655 struct jset_entry entry;
1659 struct jset_entry_blacklist_v2 {
1660 struct jset_entry entry;
1666 FS_USAGE_RESERVED = 0,
1667 FS_USAGE_INODES = 1,
1668 FS_USAGE_KEY_VERSION = 2,
1672 struct jset_entry_usage {
1673 struct jset_entry entry;
1675 } __attribute__((packed));
1677 struct jset_entry_data_usage {
1678 struct jset_entry entry;
1680 struct bch_replicas_entry r;
1681 } __attribute__((packed));
1683 struct jset_entry_clock {
1684 struct jset_entry entry;
1688 } __attribute__((packed));
1690 struct jset_entry_dev_usage_type {
1694 } __attribute__((packed));
1696 struct jset_entry_dev_usage {
1697 struct jset_entry entry;
1702 __le64 buckets_unavailable;
1704 struct jset_entry_dev_usage_type d[];
1705 } __attribute__((packed));
1708 * On disk format for a journal entry:
1709 * seq is monotonically increasing; every journal entry has its own unique
1712 * last_seq is the oldest journal entry that still has keys the btree hasn't
1713 * flushed to disk yet.
1715 * version is for on disk format changes.
1718 struct bch_csum csum;
1725 __le32 u64s; /* size of d[] in u64s */
1727 __u8 encrypted_start[0];
1729 __le16 _read_clock; /* no longer used */
1730 __le16 _write_clock;
1732 /* Sequence number of oldest dirty journal entry */
1737 struct jset_entry start[0];
1740 } __attribute__((packed, aligned(8)));
1742 LE32_BITMASK(JSET_CSUM_TYPE, struct jset, flags, 0, 4);
1743 LE32_BITMASK(JSET_BIG_ENDIAN, struct jset, flags, 4, 5);
1744 LE32_BITMASK(JSET_NO_FLUSH, struct jset, flags, 5, 6);
1746 #define BCH_JOURNAL_BUCKETS_MIN 8
1750 #define BCH_BTREE_IDS() \
1763 #define x(kwd, val) BTREE_ID_##kwd = val,
1769 #define BTREE_MAX_DEPTH 4U
1776 * On disk a btree node is a list/log of these; within each set the keys are
1783 * Highest journal entry this bset contains keys for.
1784 * If on recovery we don't see that journal entry, this bset is ignored:
1785 * this allows us to preserve the order of all index updates after a
1786 * crash, since the journal records a total order of all index updates
1787 * and anything that didn't make it to the journal doesn't get used.
1793 __le16 u64s; /* count of d[] in u64s */
1796 struct bkey_packed start[0];
1799 } __attribute__((packed, aligned(8)));
1801 LE32_BITMASK(BSET_CSUM_TYPE, struct bset, flags, 0, 4);
1803 LE32_BITMASK(BSET_BIG_ENDIAN, struct bset, flags, 4, 5);
1804 LE32_BITMASK(BSET_SEPARATE_WHITEOUTS,
1805 struct bset, flags, 5, 6);
1807 /* Sector offset within the btree node: */
1808 LE32_BITMASK(BSET_OFFSET, struct bset, flags, 16, 32);
1811 struct bch_csum csum;
1814 /* this flags field is encrypted, unlike bset->flags: */
1817 /* Closed interval: */
1818 struct bpos min_key;
1819 struct bpos max_key;
1820 struct bch_extent_ptr _ptr; /* not used anymore */
1821 struct bkey_format format;
1832 } __attribute__((packed, aligned(8)));
1834 LE64_BITMASK(BTREE_NODE_ID, struct btree_node, flags, 0, 4);
1835 LE64_BITMASK(BTREE_NODE_LEVEL, struct btree_node, flags, 4, 8);
1836 LE64_BITMASK(BTREE_NODE_NEW_EXTENT_OVERWRITE,
1837 struct btree_node, flags, 8, 9);
1839 LE64_BITMASK(BTREE_NODE_SEQ, struct btree_node, flags, 32, 64);
1841 struct btree_node_entry {
1842 struct bch_csum csum;
1853 } __attribute__((packed, aligned(8)));
1855 #endif /* _BCACHEFS_FORMAT_H */