]> git.sesse.net Git - bcachefs-tools-debian/blobdiff - libbcachefs/bcachefs_format.h
Update bcachefs sources to 39a84c99af2d bcachefs: Clamp replicas_required to replicas
[bcachefs-tools-debian] / libbcachefs / bcachefs_format.h
index 7574eccd25d4d447ee9500e9f042595fcd2db920..20604e2708d6ad76ce42dedf2fc53de2b00f7125 100644 (file)
 #include <linux/uuid.h>
 #include "vstructs.h"
 
+#ifdef __KERNEL__
+typedef uuid_t __uuid_t;
+#endif
+
 #define BITMASK(name, type, field, offset, end)                                \
-static const unsigned  name##_OFFSET = offset;                         \
-static const unsigned  name##_BITS = (end - offset);                   \
+static const __maybe_unused unsigned   name##_OFFSET = offset;         \
+static const __maybe_unused unsigned   name##_BITS = (end - offset);   \
                                                                        \
 static inline __u64 name(const type *k)                                        \
 {                                                                      \
@@ -94,9 +98,9 @@ static inline void SET_##name(type *k, __u64 v)                               \
 }
 
 #define LE_BITMASK(_bits, name, type, field, offset, end)              \
-static const unsigned  name##_OFFSET = offset;                         \
-static const unsigned  name##_BITS = (end - offset);                   \
-static const __u##_bits        name##_MAX = (1ULL << (end - offset)) - 1;      \
+static const __maybe_unused unsigned   name##_OFFSET = offset;         \
+static const __maybe_unused unsigned   name##_BITS = (end - offset);   \
+static const __maybe_unused __u##_bits name##_MAX = (1ULL << (end - offset)) - 1;\
                                                                        \
 static inline __u64 name(const type *k)                                        \
 {                                                                      \
@@ -147,7 +151,11 @@ struct bpos {
 #else
 #error edit for your odd byteorder.
 #endif
-} __packed __aligned(4);
+} __packed
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+__aligned(4)
+#endif
+;
 
 #define KEY_INODE_MAX                  ((__u64)~0ULL)
 #define KEY_OFFSET_MAX                 ((__u64)~0ULL)
@@ -250,6 +258,11 @@ struct bkey_packed {
        __u8            pad[sizeof(struct bkey) - 3];
 } __packed __aligned(8);
 
+typedef struct {
+       __le64                  lo;
+       __le64                  hi;
+} bch_le128;
+
 #define BKEY_U64s                      (sizeof(struct bkey) / sizeof(__u64))
 #define BKEY_U64s_MAX                  U8_MAX
 #define BKEY_VAL_U64s_MAX              (BKEY_U64s_MAX - BKEY_U64s)
@@ -290,18 +303,17 @@ enum bch_bkey_fields {
 struct bkey_i {
        __u64                   _data[0];
 
-       union {
-       struct {
-               /* Size of combined key and value, in u64s */
-               __u8            u64s;
-       };
-       struct {
-               struct bkey     k;
-               struct bch_val  v;
-       };
-       };
+       struct bkey     k;
+       struct bch_val  v;
 };
 
+#define POS_KEY(_pos)                                                  \
+((struct bkey) {                                                       \
+       .u64s           = BKEY_U64s,                                    \
+       .format         = KEY_FORMAT_CURRENT,                           \
+       .p              = _pos,                                         \
+})
+
 #define KEY(_inode, _offset, _size)                                    \
 ((struct bkey) {                                                       \
        .u64s           = BKEY_U64s,                                    \
@@ -318,7 +330,7 @@ static inline void bkey_init(struct bkey *k)
 #define bkey_bytes(_k)         ((_k)->u64s * sizeof(__u64))
 
 #define __BKEY_PADDED(key, pad)                                        \
-       struct { struct bkey_i key; __u64 key ## _pad[pad]; }
+       struct bkey_i key; __u64 key ## _pad[pad]
 
 /*
  * - DELETED keys are used internally to mark keys that should be ignored but
@@ -368,7 +380,10 @@ static inline void bkey_init(struct bkey *k)
        x(alloc_v4,             27)                     \
        x(backpointer,          28)                     \
        x(inode_v3,             29)                     \
-       x(bucket_gens,          30)
+       x(bucket_gens,          30)                     \
+       x(snapshot_tree,        31)                     \
+       x(logged_op_truncate,   32)                     \
+       x(logged_op_finsert,    33)
 
 enum bch_bkey_type {
 #define x(name, nr) KEY_TYPE_##name    = nr,
@@ -402,604 +417,12 @@ struct bch_set {
        struct bch_val          v;
 };
 
-/* Extents */
-
-/*
- * In extent bkeys, the value is a list of pointers (bch_extent_ptr), optionally
- * preceded by checksum/compression information (bch_extent_crc32 or
- * bch_extent_crc64).
- *
- * One major determining factor in the format of extents is how we handle and
- * represent extents that have been partially overwritten and thus trimmed:
- *
- * If an extent is not checksummed or compressed, when the extent is trimmed we
- * don't have to remember the extent we originally allocated and wrote: we can
- * merely adjust ptr->offset to point to the start of the data that is currently
- * live. The size field in struct bkey records the current (live) size of the
- * extent, and is also used to mean "size of region on disk that we point to" in
- * this case.
- *
- * Thus an extent that is not checksummed or compressed will consist only of a
- * list of bch_extent_ptrs, with none of the fields in
- * bch_extent_crc32/bch_extent_crc64.
- *
- * When an extent is checksummed or compressed, it's not possible to read only
- * the data that is currently live: we have to read the entire extent that was
- * originally written, and then return only the part of the extent that is
- * currently live.
- *
- * Thus, in addition to the current size of the extent in struct bkey, we need
- * to store the size of the originally allocated space - this is the
- * compressed_size and uncompressed_size fields in bch_extent_crc32/64. Also,
- * when the extent is trimmed, instead of modifying the offset field of the
- * pointer, we keep a second smaller offset field - "offset into the original
- * extent of the currently live region".
- *
- * The other major determining factor is replication and data migration:
- *
- * Each pointer may have its own bch_extent_crc32/64. When doing a replicated
- * write, we will initially write all the replicas in the same format, with the
- * same checksum type and compression format - however, when copygc runs later (or
- * tiering/cache promotion, anything that moves data), it is not in general
- * going to rewrite all the pointers at once - one of the replicas may be in a
- * bucket on one device that has very little fragmentation while another lives
- * in a bucket that has become heavily fragmented, and thus is being rewritten
- * sooner than the rest.
- *
- * Thus it will only move a subset of the pointers (or in the case of
- * tiering/cache promotion perhaps add a single pointer without dropping any
- * current pointers), and if the extent has been partially overwritten it must
- * write only the currently live portion (or copygc would not be able to reduce
- * fragmentation!) - which necessitates a different bch_extent_crc format for
- * the new pointer.
- *
- * But in the interests of space efficiency, we don't want to store one
- * bch_extent_crc for each pointer if we don't have to.
- *
- * Thus, a bch_extent consists of bch_extent_crc32s, bch_extent_crc64s, and
- * bch_extent_ptrs appended arbitrarily one after the other. We determine the
- * type of a given entry with a scheme similar to utf8 (except we're encoding a
- * type, not a size), encoding the type in the position of the first set bit:
- *
- * bch_extent_crc32    - 0b1
- * bch_extent_ptr      - 0b10
- * bch_extent_crc64    - 0b100
- *
- * We do it this way because bch_extent_crc32 is _very_ constrained on bits (and
- * bch_extent_crc64 is the least constrained).
- *
- * Then, each bch_extent_crc32/64 applies to the pointers that follow after it,
- * until the next bch_extent_crc32/64.
- *
- * If there are no bch_extent_crcs preceding a bch_extent_ptr, then that pointer
- * is neither checksummed nor compressed.
- */
-
 /* 128 bits, sufficient for cryptographic MACs: */
 struct bch_csum {
        __le64                  lo;
        __le64                  hi;
 } __packed __aligned(8);
 
-#define BCH_EXTENT_ENTRY_TYPES()               \
-       x(ptr,                  0)              \
-       x(crc32,                1)              \
-       x(crc64,                2)              \
-       x(crc128,               3)              \
-       x(stripe_ptr,           4)
-#define BCH_EXTENT_ENTRY_MAX   5
-
-enum bch_extent_entry_type {
-#define x(f, n) BCH_EXTENT_ENTRY_##f = n,
-       BCH_EXTENT_ENTRY_TYPES()
-#undef x
-};
-
-/* Compressed/uncompressed size are stored biased by 1: */
-struct bch_extent_crc32 {
-#if defined(__LITTLE_ENDIAN_BITFIELD)
-       __u32                   type:2,
-                               _compressed_size:7,
-                               _uncompressed_size:7,
-                               offset:7,
-                               _unused:1,
-                               csum_type:4,
-                               compression_type:4;
-       __u32                   csum;
-#elif defined (__BIG_ENDIAN_BITFIELD)
-       __u32                   csum;
-       __u32                   compression_type:4,
-                               csum_type:4,
-                               _unused:1,
-                               offset:7,
-                               _uncompressed_size:7,
-                               _compressed_size:7,
-                               type:2;
-#endif
-} __packed __aligned(8);
-
-#define CRC32_SIZE_MAX         (1U << 7)
-#define CRC32_NONCE_MAX                0
-
-struct bch_extent_crc64 {
-#if defined(__LITTLE_ENDIAN_BITFIELD)
-       __u64                   type:3,
-                               _compressed_size:9,
-                               _uncompressed_size:9,
-                               offset:9,
-                               nonce:10,
-                               csum_type:4,
-                               compression_type:4,
-                               csum_hi:16;
-#elif defined (__BIG_ENDIAN_BITFIELD)
-       __u64                   csum_hi:16,
-                               compression_type:4,
-                               csum_type:4,
-                               nonce:10,
-                               offset:9,
-                               _uncompressed_size:9,
-                               _compressed_size:9,
-                               type:3;
-#endif
-       __u64                   csum_lo;
-} __packed __aligned(8);
-
-#define CRC64_SIZE_MAX         (1U << 9)
-#define CRC64_NONCE_MAX                ((1U << 10) - 1)
-
-struct bch_extent_crc128 {
-#if defined(__LITTLE_ENDIAN_BITFIELD)
-       __u64                   type:4,
-                               _compressed_size:13,
-                               _uncompressed_size:13,
-                               offset:13,
-                               nonce:13,
-                               csum_type:4,
-                               compression_type:4;
-#elif defined (__BIG_ENDIAN_BITFIELD)
-       __u64                   compression_type:4,
-                               csum_type:4,
-                               nonce:13,
-                               offset:13,
-                               _uncompressed_size:13,
-                               _compressed_size:13,
-                               type:4;
-#endif
-       struct bch_csum         csum;
-} __packed __aligned(8);
-
-#define CRC128_SIZE_MAX                (1U << 13)
-#define CRC128_NONCE_MAX       ((1U << 13) - 1)
-
-/*
- * @reservation - pointer hasn't been written to, just reserved
- */
-struct bch_extent_ptr {
-#if defined(__LITTLE_ENDIAN_BITFIELD)
-       __u64                   type:1,
-                               cached:1,
-                               unused:1,
-                               unwritten:1,
-                               offset:44, /* 8 petabytes */
-                               dev:8,
-                               gen:8;
-#elif defined (__BIG_ENDIAN_BITFIELD)
-       __u64                   gen:8,
-                               dev:8,
-                               offset:44,
-                               unwritten:1,
-                               unused:1,
-                               cached:1,
-                               type:1;
-#endif
-} __packed __aligned(8);
-
-struct bch_extent_stripe_ptr {
-#if defined(__LITTLE_ENDIAN_BITFIELD)
-       __u64                   type:5,
-                               block:8,
-                               redundancy:4,
-                               idx:47;
-#elif defined (__BIG_ENDIAN_BITFIELD)
-       __u64                   idx:47,
-                               redundancy:4,
-                               block:8,
-                               type:5;
-#endif
-};
-
-struct bch_extent_reservation {
-#if defined(__LITTLE_ENDIAN_BITFIELD)
-       __u64                   type:6,
-                               unused:22,
-                               replicas:4,
-                               generation:32;
-#elif defined (__BIG_ENDIAN_BITFIELD)
-       __u64                   generation:32,
-                               replicas:4,
-                               unused:22,
-                               type:6;
-#endif
-};
-
-union bch_extent_entry {
-#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ ||  __BITS_PER_LONG == 64
-       unsigned long                   type;
-#elif __BITS_PER_LONG == 32
-       struct {
-               unsigned long           pad;
-               unsigned long           type;
-       };
-#else
-#error edit for your odd byteorder.
-#endif
-
-#define x(f, n) struct bch_extent_##f  f;
-       BCH_EXTENT_ENTRY_TYPES()
-#undef x
-};
-
-struct bch_btree_ptr {
-       struct bch_val          v;
-
-       __u64                   _data[0];
-       struct bch_extent_ptr   start[];
-} __packed __aligned(8);
-
-struct bch_btree_ptr_v2 {
-       struct bch_val          v;
-
-       __u64                   mem_ptr;
-       __le64                  seq;
-       __le16                  sectors_written;
-       __le16                  flags;
-       struct bpos             min_key;
-       __u64                   _data[0];
-       struct bch_extent_ptr   start[];
-} __packed __aligned(8);
-
-LE16_BITMASK(BTREE_PTR_RANGE_UPDATED,  struct bch_btree_ptr_v2, flags, 0, 1);
-
-struct bch_extent {
-       struct bch_val          v;
-
-       __u64                   _data[0];
-       union bch_extent_entry  start[];
-} __packed __aligned(8);
-
-struct bch_reservation {
-       struct bch_val          v;
-
-       __le32                  generation;
-       __u8                    nr_replicas;
-       __u8                    pad[3];
-} __packed __aligned(8);
-
-/* Maximum size (in u64s) a single pointer could be: */
-#define BKEY_EXTENT_PTR_U64s_MAX\
-       ((sizeof(struct bch_extent_crc128) +                    \
-         sizeof(struct bch_extent_ptr)) / sizeof(u64))
-
-/* Maximum possible size of an entire extent value: */
-#define BKEY_EXTENT_VAL_U64s_MAX                               \
-       (1 + BKEY_EXTENT_PTR_U64s_MAX * (BCH_REPLICAS_MAX + 1))
-
-/* * Maximum possible size of an entire extent, key + value: */
-#define BKEY_EXTENT_U64s_MAX           (BKEY_U64s + BKEY_EXTENT_VAL_U64s_MAX)
-
-/* Btree pointers don't carry around checksums: */
-#define BKEY_BTREE_PTR_VAL_U64s_MAX                            \
-       ((sizeof(struct bch_btree_ptr_v2) +                     \
-         sizeof(struct bch_extent_ptr) * BCH_REPLICAS_MAX) / sizeof(u64))
-#define BKEY_BTREE_PTR_U64s_MAX                                        \
-       (BKEY_U64s + BKEY_BTREE_PTR_VAL_U64s_MAX)
-
-/* Inodes */
-
-#define BLOCKDEV_INODE_MAX     4096
-
-#define BCACHEFS_ROOT_INO      4096
-
-struct bch_inode {
-       struct bch_val          v;
-
-       __le64                  bi_hash_seed;
-       __le32                  bi_flags;
-       __le16                  bi_mode;
-       __u8                    fields[0];
-} __packed __aligned(8);
-
-struct bch_inode_v2 {
-       struct bch_val          v;
-
-       __le64                  bi_journal_seq;
-       __le64                  bi_hash_seed;
-       __le64                  bi_flags;
-       __le16                  bi_mode;
-       __u8                    fields[0];
-} __packed __aligned(8);
-
-struct bch_inode_v3 {
-       struct bch_val          v;
-
-       __le64                  bi_journal_seq;
-       __le64                  bi_hash_seed;
-       __le64                  bi_flags;
-       __le64                  bi_sectors;
-       __le64                  bi_size;
-       __le64                  bi_version;
-       __u8                    fields[0];
-} __packed __aligned(8);
-
-#define INODEv3_FIELDS_START_INITIAL   6
-#define INODEv3_FIELDS_START_CUR       (offsetof(struct bch_inode_v3, fields) / sizeof(u64))
-
-struct bch_inode_generation {
-       struct bch_val          v;
-
-       __le32                  bi_generation;
-       __le32                  pad;
-} __packed __aligned(8);
-
-/*
- * bi_subvol and bi_parent_subvol are only set for subvolume roots:
- */
-
-#define BCH_INODE_FIELDS_v2()                  \
-       x(bi_atime,                     96)     \
-       x(bi_ctime,                     96)     \
-       x(bi_mtime,                     96)     \
-       x(bi_otime,                     96)     \
-       x(bi_size,                      64)     \
-       x(bi_sectors,                   64)     \
-       x(bi_uid,                       32)     \
-       x(bi_gid,                       32)     \
-       x(bi_nlink,                     32)     \
-       x(bi_generation,                32)     \
-       x(bi_dev,                       32)     \
-       x(bi_data_checksum,             8)      \
-       x(bi_compression,               8)      \
-       x(bi_project,                   32)     \
-       x(bi_background_compression,    8)      \
-       x(bi_data_replicas,             8)      \
-       x(bi_promote_target,            16)     \
-       x(bi_foreground_target,         16)     \
-       x(bi_background_target,         16)     \
-       x(bi_erasure_code,              16)     \
-       x(bi_fields_set,                16)     \
-       x(bi_dir,                       64)     \
-       x(bi_dir_offset,                64)     \
-       x(bi_subvol,                    32)     \
-       x(bi_parent_subvol,             32)
-
-#define BCH_INODE_FIELDS_v3()                  \
-       x(bi_atime,                     96)     \
-       x(bi_ctime,                     96)     \
-       x(bi_mtime,                     96)     \
-       x(bi_otime,                     96)     \
-       x(bi_uid,                       32)     \
-       x(bi_gid,                       32)     \
-       x(bi_nlink,                     32)     \
-       x(bi_generation,                32)     \
-       x(bi_dev,                       32)     \
-       x(bi_data_checksum,             8)      \
-       x(bi_compression,               8)      \
-       x(bi_project,                   32)     \
-       x(bi_background_compression,    8)      \
-       x(bi_data_replicas,             8)      \
-       x(bi_promote_target,            16)     \
-       x(bi_foreground_target,         16)     \
-       x(bi_background_target,         16)     \
-       x(bi_erasure_code,              16)     \
-       x(bi_fields_set,                16)     \
-       x(bi_dir,                       64)     \
-       x(bi_dir_offset,                64)     \
-       x(bi_subvol,                    32)     \
-       x(bi_parent_subvol,             32)     \
-       x(bi_nocow,                     8)
-
-/* subset of BCH_INODE_FIELDS */
-#define BCH_INODE_OPTS()                       \
-       x(data_checksum,                8)      \
-       x(compression,                  8)      \
-       x(project,                      32)     \
-       x(background_compression,       8)      \
-       x(data_replicas,                8)      \
-       x(promote_target,               16)     \
-       x(foreground_target,            16)     \
-       x(background_target,            16)     \
-       x(erasure_code,                 16)     \
-       x(nocow,                        8)
-
-enum inode_opt_id {
-#define x(name, ...)                           \
-       Inode_opt_##name,
-       BCH_INODE_OPTS()
-#undef  x
-       Inode_opt_nr,
-};
-
-enum {
-       /*
-        * User flags (get/settable with FS_IOC_*FLAGS, correspond to FS_*_FL
-        * flags)
-        */
-       __BCH_INODE_SYNC                = 0,
-       __BCH_INODE_IMMUTABLE           = 1,
-       __BCH_INODE_APPEND              = 2,
-       __BCH_INODE_NODUMP              = 3,
-       __BCH_INODE_NOATIME             = 4,
-
-       __BCH_INODE_I_SIZE_DIRTY        = 5,
-       __BCH_INODE_I_SECTORS_DIRTY     = 6,
-       __BCH_INODE_UNLINKED            = 7,
-       __BCH_INODE_BACKPTR_UNTRUSTED   = 8,
-
-       /* bits 20+ reserved for packed fields below: */
-};
-
-#define BCH_INODE_SYNC         (1 << __BCH_INODE_SYNC)
-#define BCH_INODE_IMMUTABLE    (1 << __BCH_INODE_IMMUTABLE)
-#define BCH_INODE_APPEND       (1 << __BCH_INODE_APPEND)
-#define BCH_INODE_NODUMP       (1 << __BCH_INODE_NODUMP)
-#define BCH_INODE_NOATIME      (1 << __BCH_INODE_NOATIME)
-#define BCH_INODE_I_SIZE_DIRTY (1 << __BCH_INODE_I_SIZE_DIRTY)
-#define BCH_INODE_I_SECTORS_DIRTY (1 << __BCH_INODE_I_SECTORS_DIRTY)
-#define BCH_INODE_UNLINKED     (1 << __BCH_INODE_UNLINKED)
-#define BCH_INODE_BACKPTR_UNTRUSTED (1 << __BCH_INODE_BACKPTR_UNTRUSTED)
-
-LE32_BITMASK(INODE_STR_HASH,   struct bch_inode, bi_flags, 20, 24);
-LE32_BITMASK(INODE_NR_FIELDS,  struct bch_inode, bi_flags, 24, 31);
-LE32_BITMASK(INODE_NEW_VARINT, struct bch_inode, bi_flags, 31, 32);
-
-LE64_BITMASK(INODEv2_STR_HASH, struct bch_inode_v2, bi_flags, 20, 24);
-LE64_BITMASK(INODEv2_NR_FIELDS,        struct bch_inode_v2, bi_flags, 24, 31);
-
-LE64_BITMASK(INODEv3_STR_HASH, struct bch_inode_v3, bi_flags, 20, 24);
-LE64_BITMASK(INODEv3_NR_FIELDS,        struct bch_inode_v3, bi_flags, 24, 31);
-
-LE64_BITMASK(INODEv3_FIELDS_START,
-                               struct bch_inode_v3, bi_flags, 31, 36);
-LE64_BITMASK(INODEv3_MODE,     struct bch_inode_v3, bi_flags, 36, 52);
-
-/* Dirents */
-
-/*
- * Dirents (and xattrs) have to implement string lookups; since our b-tree
- * doesn't support arbitrary length strings for the key, we instead index by a
- * 64 bit hash (currently truncated sha1) of the string, stored in the offset
- * field of the key - using linear probing to resolve hash collisions. This also
- * provides us with the readdir cookie posix requires.
- *
- * Linear probing requires us to use whiteouts for deletions, in the event of a
- * collision:
- */
-
-struct bch_dirent {
-       struct bch_val          v;
-
-       /* Target inode number: */
-       union {
-       __le64                  d_inum;
-       struct {                /* DT_SUBVOL */
-       __le32                  d_child_subvol;
-       __le32                  d_parent_subvol;
-       };
-       };
-
-       /*
-        * Copy of mode bits 12-15 from the target inode - so userspace can get
-        * the filetype without having to do a stat()
-        */
-       __u8                    d_type;
-
-       __u8                    d_name[];
-} __packed __aligned(8);
-
-#define DT_SUBVOL      16
-#define BCH_DT_MAX     17
-
-#define BCH_NAME_MAX   ((unsigned) (U8_MAX * sizeof(u64) -             \
-                        sizeof(struct bkey) -                          \
-                        offsetof(struct bch_dirent, d_name)))
-
-/* Xattrs */
-
-#define KEY_TYPE_XATTR_INDEX_USER                      0
-#define KEY_TYPE_XATTR_INDEX_POSIX_ACL_ACCESS  1
-#define KEY_TYPE_XATTR_INDEX_POSIX_ACL_DEFAULT 2
-#define KEY_TYPE_XATTR_INDEX_TRUSTED                   3
-#define KEY_TYPE_XATTR_INDEX_SECURITY          4
-
-struct bch_xattr {
-       struct bch_val          v;
-       __u8                    x_type;
-       __u8                    x_name_len;
-       __le16                  x_val_len;
-       __u8                    x_name[];
-} __packed __aligned(8);
-
-/* Bucket/allocation information: */
-
-struct bch_alloc {
-       struct bch_val          v;
-       __u8                    fields;
-       __u8                    gen;
-       __u8                    data[];
-} __packed __aligned(8);
-
-#define BCH_ALLOC_FIELDS_V1()                  \
-       x(read_time,            16)             \
-       x(write_time,           16)             \
-       x(data_type,            8)              \
-       x(dirty_sectors,        16)             \
-       x(cached_sectors,       16)             \
-       x(oldest_gen,           8)              \
-       x(stripe,               32)             \
-       x(stripe_redundancy,    8)
-
-enum {
-#define x(name, _bits) BCH_ALLOC_FIELD_V1_##name,
-       BCH_ALLOC_FIELDS_V1()
-#undef x
-};
-
-struct bch_alloc_v2 {
-       struct bch_val          v;
-       __u8                    nr_fields;
-       __u8                    gen;
-       __u8                    oldest_gen;
-       __u8                    data_type;
-       __u8                    data[];
-} __packed __aligned(8);
-
-#define BCH_ALLOC_FIELDS_V2()                  \
-       x(read_time,            64)             \
-       x(write_time,           64)             \
-       x(dirty_sectors,        32)             \
-       x(cached_sectors,       32)             \
-       x(stripe,               32)             \
-       x(stripe_redundancy,    8)
-
-struct bch_alloc_v3 {
-       struct bch_val          v;
-       __le64                  journal_seq;
-       __le32                  flags;
-       __u8                    nr_fields;
-       __u8                    gen;
-       __u8                    oldest_gen;
-       __u8                    data_type;
-       __u8                    data[];
-} __packed __aligned(8);
-
-LE32_BITMASK(BCH_ALLOC_V3_NEED_DISCARD,struct bch_alloc_v3, flags,  0,  1)
-LE32_BITMASK(BCH_ALLOC_V3_NEED_INC_GEN,struct bch_alloc_v3, flags,  1,  2)
-
-struct bch_alloc_v4 {
-       struct bch_val          v;
-       __u64                   journal_seq;
-       __u32                   flags;
-       __u8                    gen;
-       __u8                    oldest_gen;
-       __u8                    data_type;
-       __u8                    stripe_redundancy;
-       __u32                   dirty_sectors;
-       __u32                   cached_sectors;
-       __u64                   io_time[2];
-       __u32                   stripe;
-       __u32                   nr_external_backpointers;
-} __packed __aligned(8);
-
-#define BCH_ALLOC_V4_U64s_V0   6
-#define BCH_ALLOC_V4_U64s      (sizeof(struct bch_alloc_v4) / sizeof(u64))
-
-BITMASK(BCH_ALLOC_V4_NEED_DISCARD,     struct bch_alloc_v4, flags,  0,  1)
-BITMASK(BCH_ALLOC_V4_NEED_INC_GEN,     struct bch_alloc_v4, flags,  1,  2)
-BITMASK(BCH_ALLOC_V4_BACKPOINTERS_START,struct bch_alloc_v4, flags,  2,  8)
-BITMASK(BCH_ALLOC_V4_NR_BACKPOINTERS,  struct bch_alloc_v4, flags,  8,  14)
-
-#define BCH_ALLOC_V4_NR_BACKPOINTERS_MAX       40
-
 struct bch_backpointer {
        struct bch_val          v;
        __u8                    btree_id;
@@ -1010,130 +433,6 @@ struct bch_backpointer {
        struct bpos             pos;
 } __packed __aligned(8);
 
-#define KEY_TYPE_BUCKET_GENS_BITS      8
-#define KEY_TYPE_BUCKET_GENS_NR                (1U << KEY_TYPE_BUCKET_GENS_BITS)
-#define KEY_TYPE_BUCKET_GENS_MASK      (KEY_TYPE_BUCKET_GENS_NR - 1)
-
-struct bch_bucket_gens {
-       struct bch_val          v;
-       u8                      gens[KEY_TYPE_BUCKET_GENS_NR];
-} __packed __aligned(8);
-
-/* Quotas: */
-
-enum quota_types {
-       QTYP_USR                = 0,
-       QTYP_GRP                = 1,
-       QTYP_PRJ                = 2,
-       QTYP_NR                 = 3,
-};
-
-enum quota_counters {
-       Q_SPC                   = 0,
-       Q_INO                   = 1,
-       Q_COUNTERS              = 2,
-};
-
-struct bch_quota_counter {
-       __le64                  hardlimit;
-       __le64                  softlimit;
-};
-
-struct bch_quota {
-       struct bch_val          v;
-       struct bch_quota_counter c[Q_COUNTERS];
-} __packed __aligned(8);
-
-/* Erasure coding */
-
-struct bch_stripe {
-       struct bch_val          v;
-       __le16                  sectors;
-       __u8                    algorithm;
-       __u8                    nr_blocks;
-       __u8                    nr_redundant;
-
-       __u8                    csum_granularity_bits;
-       __u8                    csum_type;
-       __u8                    pad;
-
-       struct bch_extent_ptr   ptrs[];
-} __packed __aligned(8);
-
-/* Reflink: */
-
-struct bch_reflink_p {
-       struct bch_val          v;
-       __le64                  idx;
-       /*
-        * A reflink pointer might point to an indirect extent which is then
-        * later split (by copygc or rebalance). If we only pointed to part of
-        * the original indirect extent, and then one of the fragments is
-        * outside the range we point to, we'd leak a refcount: so when creating
-        * reflink pointers, we need to store pad values to remember the full
-        * range we were taking a reference on.
-        */
-       __le32                  front_pad;
-       __le32                  back_pad;
-} __packed __aligned(8);
-
-struct bch_reflink_v {
-       struct bch_val          v;
-       __le64                  refcount;
-       union bch_extent_entry  start[0];
-       __u64                   _data[0];
-} __packed __aligned(8);
-
-struct bch_indirect_inline_data {
-       struct bch_val          v;
-       __le64                  refcount;
-       u8                      data[0];
-};
-
-/* Inline data */
-
-struct bch_inline_data {
-       struct bch_val          v;
-       u8                      data[0];
-};
-
-/* Subvolumes: */
-
-#define SUBVOL_POS_MIN         POS(0, 1)
-#define SUBVOL_POS_MAX         POS(0, S32_MAX)
-#define BCACHEFS_ROOT_SUBVOL   1
-
-struct bch_subvolume {
-       struct bch_val          v;
-       __le32                  flags;
-       __le32                  snapshot;
-       __le64                  inode;
-};
-
-LE32_BITMASK(BCH_SUBVOLUME_RO,         struct bch_subvolume, flags,  0,  1)
-/*
- * We need to know whether a subvolume is a snapshot so we can know whether we
- * can delete it (or whether it should just be rm -rf'd)
- */
-LE32_BITMASK(BCH_SUBVOLUME_SNAP,       struct bch_subvolume, flags,  1,  2)
-LE32_BITMASK(BCH_SUBVOLUME_UNLINKED,   struct bch_subvolume, flags,  2,  3)
-
-/* Snapshots */
-
-struct bch_snapshot {
-       struct bch_val          v;
-       __le32                  flags;
-       __le32                  parent;
-       __le32                  children[2];
-       __le32                  subvol;
-       __le32                  pad;
-};
-
-LE32_BITMASK(BCH_SNAPSHOT_DELETED,     struct bch_snapshot, flags,  0,  1)
-
-/* True if a subvolume points to this snapshot node: */
-LE32_BITMASK(BCH_SNAPSHOT_SUBVOL,      struct bch_snapshot, flags,  1,  2)
-
 /* LRU btree: */
 
 struct bch_lru {
@@ -1152,17 +451,34 @@ struct bch_sb_field {
 };
 
 #define BCH_SB_FIELDS()                                \
-       x(journal,      0)                      \
-       x(members,      1)                      \
-       x(crypt,        2)                      \
-       x(replicas_v0,  3)                      \
-       x(quota,        4)                      \
-       x(disk_groups,  5)                      \
-       x(clean,        6)                      \
-       x(replicas,     7)                      \
-       x(journal_seq_blacklist, 8)             \
-       x(journal_v2,   9)                      \
-       x(counters,     10)
+       x(journal,                      0)      \
+       x(members_v1,                   1)      \
+       x(crypt,                        2)      \
+       x(replicas_v0,                  3)      \
+       x(quota,                        4)      \
+       x(disk_groups,                  5)      \
+       x(clean,                        6)      \
+       x(replicas,                     7)      \
+       x(journal_seq_blacklist,        8)      \
+       x(journal_v2,                   9)      \
+       x(counters,                     10)     \
+       x(members_v2,                   11)     \
+       x(errors,                       12)     \
+       x(ext,                          13)     \
+       x(downgrade,                    14)
+
+#include "alloc_background_format.h"
+#include "extents_format.h"
+#include "reflink_format.h"
+#include "ec_format.h"
+#include "inode_format.h"
+#include "dirent_format.h"
+#include "xattr_format.h"
+#include "quota_format.h"
+#include "logged_ops_format.h"
+#include "snapshot_format.h"
+#include "subvolume_format.h"
+#include "sb-counters_format.h"
 
 enum bch_sb_field_type {
 #define x(f, nr)       BCH_SB_FIELD_##f = nr,
@@ -1183,7 +499,7 @@ enum bch_sb_field_type {
 
 struct bch_sb_field_journal {
        struct bch_sb_field     field;
-       __le64                  buckets[0];
+       __le64                  buckets[];
 };
 
 struct bch_sb_field_journal_v2 {
@@ -1192,32 +508,64 @@ struct bch_sb_field_journal_v2 {
        struct bch_sb_field_journal_v2_entry {
                __le64          start;
                __le64          nr;
-       }                       d[0];
+       }                       d[];
 };
 
-/* BCH_SB_FIELD_members: */
+/* BCH_SB_FIELD_members_v1: */
 
 #define BCH_MIN_NR_NBUCKETS    (1 << 6)
 
+#define BCH_IOPS_MEASUREMENTS()                        \
+       x(seqread,      0)                      \
+       x(seqwrite,     1)                      \
+       x(randread,     2)                      \
+       x(randwrite,    3)
+
+enum bch_iops_measurement {
+#define x(t, n) BCH_IOPS_##t = n,
+       BCH_IOPS_MEASUREMENTS()
+#undef x
+       BCH_IOPS_NR
+};
+
+#define BCH_MEMBER_ERROR_TYPES()               \
+       x(read,         0)                      \
+       x(write,        1)                      \
+       x(checksum,     2)
+
+enum bch_member_error_type {
+#define x(t, n) BCH_MEMBER_ERROR_##t = n,
+       BCH_MEMBER_ERROR_TYPES()
+#undef x
+       BCH_MEMBER_ERROR_NR
+};
+
 struct bch_member {
-       uuid_le                 uuid;
+       __uuid_t                uuid;
        __le64                  nbuckets;       /* device size */
        __le16                  first_bucket;   /* index of first bucket used */
        __le16                  bucket_size;    /* sectors */
        __le32                  pad;
        __le64                  last_mount;     /* time_t */
 
-       __le64                  flags[2];
+       __le64                  flags;
+       __le32                  iops[4];
+       __le64                  errors[BCH_MEMBER_ERROR_NR];
+       __le64                  errors_at_reset[BCH_MEMBER_ERROR_NR];
+       __le64                  errors_reset_time;
+       __le64                  seq;
 };
 
-LE64_BITMASK(BCH_MEMBER_STATE,         struct bch_member, flags[0],  0,  4)
+#define BCH_MEMBER_V1_BYTES    56
+
+LE64_BITMASK(BCH_MEMBER_STATE,         struct bch_member, flags,  0,  4)
 /* 4-14 unused, was TIER, HAS_(META)DATA, REPLACEMENT */
-LE64_BITMASK(BCH_MEMBER_DISCARD,       struct bch_member, flags[0], 14, 15)
-LE64_BITMASK(BCH_MEMBER_DATA_ALLOWED,  struct bch_member, flags[0], 15, 20)
-LE64_BITMASK(BCH_MEMBER_GROUP,         struct bch_member, flags[0], 20, 28)
-LE64_BITMASK(BCH_MEMBER_DURABILITY,    struct bch_member, flags[0], 28, 30)
+LE64_BITMASK(BCH_MEMBER_DISCARD,       struct bch_member, flags, 14, 15)
+LE64_BITMASK(BCH_MEMBER_DATA_ALLOWED,  struct bch_member, flags, 15, 20)
+LE64_BITMASK(BCH_MEMBER_GROUP,         struct bch_member, flags, 20, 28)
+LE64_BITMASK(BCH_MEMBER_DURABILITY,    struct bch_member, flags, 28, 30)
 LE64_BITMASK(BCH_MEMBER_FREESPACE_INITIALIZED,
-                                       struct bch_member, flags[0], 30, 31)
+                                       struct bch_member, flags, 30, 31)
 
 #if 0
 LE64_BITMASK(BCH_MEMBER_NR_READ_ERRORS,        struct bch_member, flags[1], 0,  20);
@@ -1237,9 +585,16 @@ enum bch_member_state {
        BCH_MEMBER_STATE_NR
 };
 
-struct bch_sb_field_members {
+struct bch_sb_field_members_v1 {
        struct bch_sb_field     field;
-       struct bch_member       members[0];
+       struct bch_member       _members[]; //Members are now variable size
+};
+
+struct bch_sb_field_members_v2 {
+       struct bch_sb_field     field;
+       __le16                  member_bytes; //size of single member entry
+       u8                      pad[6];
+       struct bch_member       _members[];
 };
 
 /* BCH_SB_FIELD_crypt: */
@@ -1253,10 +608,10 @@ struct bch_key {
 };
 
 #define BCH_KEY_MAGIC                                  \
-       (((u64) 'b' <<  0)|((u64) 'c' <<  8)|           \
-        ((u64) 'h' << 16)|((u64) '*' << 24)|           \
-        ((u64) '*' << 32)|((u64) 'k' << 40)|           \
-        ((u64) 'e' << 48)|((u64) 'y' << 56))
+       (((__u64) 'b' <<  0)|((__u64) 'c' <<  8)|               \
+        ((__u64) 'h' << 16)|((__u64) '*' << 24)|               \
+        ((__u64) '*' << 32)|((__u64) 'k' << 40)|               \
+        ((__u64) 'e' << 48)|((__u64) 'y' << 56))
 
 struct bch_encrypted_key {
        __le64                  magic;
@@ -1345,7 +700,7 @@ struct bch_sb_field_replicas_v0 {
        struct bch_replicas_entry_v0 entries[];
 } __packed __aligned(8);
 
-struct bch_replicas_entry {
+struct bch_replicas_entry_v1 {
        __u8                    data_type;
        __u8                    nr_devs;
        __u8                    nr_required;
@@ -1357,24 +712,7 @@ struct bch_replicas_entry {
 
 struct bch_sb_field_replicas {
        struct bch_sb_field     field;
-       struct bch_replicas_entry entries[];
-} __packed __aligned(8);
-
-/* BCH_SB_FIELD_quota: */
-
-struct bch_sb_quota_counter {
-       __le32                          timelimit;
-       __le32                          warnlimit;
-};
-
-struct bch_sb_quota_type {
-       __le64                          flags;
-       struct bch_sb_quota_counter     c[Q_COUNTERS];
-};
-
-struct bch_sb_field_quota {
-       struct bch_sb_field             field;
-       struct bch_sb_quota_type        q[QTYP_NR];
+       struct bch_replicas_entry_v1 entries[];
 } __packed __aligned(8);
 
 /* BCH_SB_FIELD_disk_groups: */
@@ -1392,101 +730,9 @@ LE64_BITMASK(BCH_GROUP_PARENT,           struct bch_disk_group, flags[0], 6, 24)
 
 struct bch_sb_field_disk_groups {
        struct bch_sb_field     field;
-       struct bch_disk_group   entries[0];
+       struct bch_disk_group   entries[];
 } __packed __aligned(8);
 
-/* BCH_SB_FIELD_counters */
-
-#define BCH_PERSISTENT_COUNTERS()                              \
-       x(io_read,                                      0)      \
-       x(io_write,                                     1)      \
-       x(io_move,                                      2)      \
-       x(bucket_invalidate,                            3)      \
-       x(bucket_discard,                               4)      \
-       x(bucket_alloc,                                 5)      \
-       x(bucket_alloc_fail,                            6)      \
-       x(btree_cache_scan,                             7)      \
-       x(btree_cache_reap,                             8)      \
-       x(btree_cache_cannibalize,                      9)      \
-       x(btree_cache_cannibalize_lock,                 10)     \
-       x(btree_cache_cannibalize_lock_fail,            11)     \
-       x(btree_cache_cannibalize_unlock,               12)     \
-       x(btree_node_write,                             13)     \
-       x(btree_node_read,                              14)     \
-       x(btree_node_compact,                           15)     \
-       x(btree_node_merge,                             16)     \
-       x(btree_node_split,                             17)     \
-       x(btree_node_rewrite,                           18)     \
-       x(btree_node_alloc,                             19)     \
-       x(btree_node_free,                              20)     \
-       x(btree_node_set_root,                          21)     \
-       x(btree_path_relock_fail,                       22)     \
-       x(btree_path_upgrade_fail,                      23)     \
-       x(btree_reserve_get_fail,                       24)     \
-       x(journal_entry_full,                           25)     \
-       x(journal_full,                                 26)     \
-       x(journal_reclaim_finish,                       27)     \
-       x(journal_reclaim_start,                        28)     \
-       x(journal_write,                                29)     \
-       x(read_promote,                                 30)     \
-       x(read_bounce,                                  31)     \
-       x(read_split,                                   33)     \
-       x(read_retry,                                   32)     \
-       x(read_reuse_race,                              34)     \
-       x(move_extent_read,                             35)     \
-       x(move_extent_write,                            36)     \
-       x(move_extent_finish,                           37)     \
-       x(move_extent_fail,                             38)     \
-       x(move_extent_alloc_mem_fail,                   39)     \
-       x(copygc,                                       40)     \
-       x(copygc_wait,                                  41)     \
-       x(gc_gens_end,                                  42)     \
-       x(gc_gens_start,                                43)     \
-       x(trans_blocked_journal_reclaim,                44)     \
-       x(trans_restart_btree_node_reused,              45)     \
-       x(trans_restart_btree_node_split,               46)     \
-       x(trans_restart_fault_inject,                   47)     \
-       x(trans_restart_iter_upgrade,                   48)     \
-       x(trans_restart_journal_preres_get,             49)     \
-       x(trans_restart_journal_reclaim,                50)     \
-       x(trans_restart_journal_res_get,                51)     \
-       x(trans_restart_key_cache_key_realloced,        52)     \
-       x(trans_restart_key_cache_raced,                53)     \
-       x(trans_restart_mark_replicas,                  54)     \
-       x(trans_restart_mem_realloced,                  55)     \
-       x(trans_restart_memory_allocation_failure,      56)     \
-       x(trans_restart_relock,                         57)     \
-       x(trans_restart_relock_after_fill,              58)     \
-       x(trans_restart_relock_key_cache_fill,          59)     \
-       x(trans_restart_relock_next_node,               60)     \
-       x(trans_restart_relock_parent_for_fill,         61)     \
-       x(trans_restart_relock_path,                    62)     \
-       x(trans_restart_relock_path_intent,             63)     \
-       x(trans_restart_too_many_iters,                 64)     \
-       x(trans_restart_traverse,                       65)     \
-       x(trans_restart_upgrade,                        66)     \
-       x(trans_restart_would_deadlock,                 67)     \
-       x(trans_restart_would_deadlock_write,           68)     \
-       x(trans_restart_injected,                       69)     \
-       x(trans_restart_key_cache_upgrade,              70)     \
-       x(trans_traverse_all,                           71)     \
-       x(transaction_commit,                           72)     \
-       x(write_super,                                  73)     \
-       x(trans_restart_would_deadlock_recursion_limit, 74)     \
-       x(trans_restart_write_buffer_flush,             75)
-
-enum bch_persistent_counters {
-#define x(t, n, ...) BCH_COUNTER_##t,
-       BCH_PERSISTENT_COUNTERS()
-#undef x
-       BCH_COUNTER_NR
-};
-
-struct bch_sb_field_counters {
-       struct bch_sb_field     field;
-       __le64                  d[0];
-};
-
 /*
  * On clean shutdown, store btree roots and current journal sequence number in
  * the superblock:
@@ -1498,10 +744,8 @@ struct jset_entry {
        __u8                    type; /* designates what this jset holds */
        __u8                    pad[3];
 
-       union {
-               struct bkey_i   start[0];
-               __u64           _data[0];
-       };
+       struct bkey_i           start[0];
+       __u64                   _data[];
 };
 
 struct bch_sb_field_clean {
@@ -1512,10 +756,8 @@ struct bch_sb_field_clean {
        __le16                  _write_clock;
        __le64                  journal_seq;
 
-       union {
-               struct jset_entry start[0];
-               __u64           _data[0];
-       };
+       struct jset_entry       start[0];
+       __u64                   _data[];
 };
 
 struct journal_seq_blacklist_entry {
@@ -1525,11 +767,36 @@ struct journal_seq_blacklist_entry {
 
 struct bch_sb_field_journal_seq_blacklist {
        struct bch_sb_field     field;
+       struct journal_seq_blacklist_entry start[];
+};
+
+struct bch_sb_field_errors {
+       struct bch_sb_field     field;
+       struct bch_sb_field_error_entry {
+               __le64          v;
+               __le64          last_error_time;
+       }                       entries[];
+};
 
-       union {
-               struct journal_seq_blacklist_entry start[0];
-               __u64           _data[0];
-       };
+LE64_BITMASK(BCH_SB_ERROR_ENTRY_ID,    struct bch_sb_field_error_entry, v,  0, 16);
+LE64_BITMASK(BCH_SB_ERROR_ENTRY_NR,    struct bch_sb_field_error_entry, v, 16, 64);
+
+struct bch_sb_field_ext {
+       struct bch_sb_field     field;
+       __le64                  recovery_passes_required[2];
+       __le64                  errors_silent[8];
+};
+
+struct bch_sb_field_downgrade_entry {
+       __le16                  version;
+       __le64                  recovery_passes[2];
+       __le16                  nr_errors;
+       __le16                  errors[] __counted_by(nr_errors);
+} __packed __aligned(2);
+
+struct bch_sb_field_downgrade {
+       struct bch_sb_field     field;
+       struct bch_sb_field_downgrade_entry entries[];
 };
 
 /* Superblock: */
@@ -1539,27 +806,43 @@ struct bch_sb_field_journal_seq_blacklist {
  * One common version number for all on disk data structures - superblock, btree
  * nodes, journal entries
  */
-#define BCH_JSET_VERSION_OLD                   2
-#define BCH_BSET_VERSION_OLD                   3
-
-#define BCH_METADATA_VERSIONS()                                \
-       x(bkey_renumber,                10)             \
-       x(inode_btree_change,           11)             \
-       x(snapshot,                     12)             \
-       x(inode_backpointers,           13)             \
-       x(btree_ptr_sectors_written,    14)             \
-       x(snapshot_2,                   15)             \
-       x(reflink_p_fix,                16)             \
-       x(subvol_dirent,                17)             \
-       x(inode_v2,                     18)             \
-       x(freespace,                    19)             \
-       x(alloc_v4,                     20)             \
-       x(new_data_types,               21)             \
-       x(backpointers,                 22)             \
-       x(inode_v3,                     23)             \
-       x(unwritten_extents,            24)             \
-       x(bucket_gens,                  25)             \
-       x(lru_v2,                       26)
+#define BCH_VERSION_MAJOR(_v)          ((__u16) ((_v) >> 10))
+#define BCH_VERSION_MINOR(_v)          ((__u16) ((_v) & ~(~0U << 10)))
+#define BCH_VERSION(_major, _minor)    (((_major) << 10)|(_minor) << 0)
+
+/*
+ * field 1:            version name
+ * field 2:            BCH_VERSION(major, minor)
+ * field 3:            recovery passess required on upgrade
+ */
+#define BCH_METADATA_VERSIONS()                                                \
+       x(bkey_renumber,                BCH_VERSION(0, 10))             \
+       x(inode_btree_change,           BCH_VERSION(0, 11))             \
+       x(snapshot,                     BCH_VERSION(0, 12))             \
+       x(inode_backpointers,           BCH_VERSION(0, 13))             \
+       x(btree_ptr_sectors_written,    BCH_VERSION(0, 14))             \
+       x(snapshot_2,                   BCH_VERSION(0, 15))             \
+       x(reflink_p_fix,                BCH_VERSION(0, 16))             \
+       x(subvol_dirent,                BCH_VERSION(0, 17))             \
+       x(inode_v2,                     BCH_VERSION(0, 18))             \
+       x(freespace,                    BCH_VERSION(0, 19))             \
+       x(alloc_v4,                     BCH_VERSION(0, 20))             \
+       x(new_data_types,               BCH_VERSION(0, 21))             \
+       x(backpointers,                 BCH_VERSION(0, 22))             \
+       x(inode_v3,                     BCH_VERSION(0, 23))             \
+       x(unwritten_extents,            BCH_VERSION(0, 24))             \
+       x(bucket_gens,                  BCH_VERSION(0, 25))             \
+       x(lru_v2,                       BCH_VERSION(0, 26))             \
+       x(fragmentation_lru,            BCH_VERSION(0, 27))             \
+       x(no_bps_in_alloc_keys,         BCH_VERSION(0, 28))             \
+       x(snapshot_trees,               BCH_VERSION(0, 29))             \
+       x(major_minor,                  BCH_VERSION(1,  0))             \
+       x(snapshot_skiplists,           BCH_VERSION(1,  1))             \
+       x(deleted_inodes,               BCH_VERSION(1,  2))             \
+       x(rebalance_work,               BCH_VERSION(1,  3))             \
+       x(member_seq,                   BCH_VERSION(1,  4))             \
+       x(subvolume_fs_parent,          BCH_VERSION(1,  5))             \
+       x(btree_subvolume_children,     BCH_VERSION(1,  6))
 
 enum bcachefs_metadata_version {
        bcachefs_metadata_version_min = 9,
@@ -1569,13 +852,16 @@ enum bcachefs_metadata_version {
        bcachefs_metadata_version_max
 };
 
+static const __maybe_unused
+unsigned bcachefs_metadata_required_upgrade_below = bcachefs_metadata_version_rebalance_work;
+
 #define bcachefs_metadata_version_current      (bcachefs_metadata_version_max - 1)
 
 #define BCH_SB_SECTOR                  8
 #define BCH_SB_MEMBERS_MAX             64 /* XXX kill */
 
 struct bch_sb_layout {
-       uuid_le                 magic;  /* bcachefs superblock UUID */
+       __uuid_t                magic;  /* bcachefs superblock UUID */
        __u8                    layout_type;
        __u8                    sb_max_size_bits; /* base 2 of 512 byte sectors */
        __u8                    nr_superblocks;
@@ -1606,9 +892,9 @@ struct bch_sb {
        __le16                  version;
        __le16                  version_min;
        __le16                  pad[2];
-       uuid_le                 magic;
-       uuid_le                 uuid;
-       uuid_le                 user_uuid;
+       __uuid_t                magic;
+       __uuid_t                uuid;
+       __uuid_t                user_uuid;
        __u8                    label[BCH_SB_LABEL_SIZE];
        __le64                  offset;
        __le64                  seq;
@@ -1622,16 +908,15 @@ struct bch_sb {
        __le32                  time_base_hi;
        __le32                  time_precision;
 
-       __le64                  flags[8];
+       __le64                  flags[7];
+       __le64                  write_time;
        __le64                  features[2];
        __le64                  compat[2];
 
        struct bch_sb_layout    layout;
 
-       union {
-               struct bch_sb_field start[0];
-               __le64          _data[0];
-       };
+       struct bch_sb_field     start[0];
+       __le64                  _data[];
 } __packed __aligned(8);
 
 /*
@@ -1675,7 +960,7 @@ LE64_BITMASK(BCH_SB_HAS_TOPOLOGY_ERRORS,struct bch_sb, flags[0], 61, 62);
 LE64_BITMASK(BCH_SB_BIG_ENDIAN,                struct bch_sb, flags[0], 62, 63);
 
 LE64_BITMASK(BCH_SB_STR_HASH_TYPE,     struct bch_sb, flags[1],  0,  4);
-LE64_BITMASK(BCH_SB_COMPRESSION_TYPE,  struct bch_sb, flags[1],  4,  8);
+LE64_BITMASK(BCH_SB_COMPRESSION_TYPE_LO,struct bch_sb, flags[1],  4,  8);
 LE64_BITMASK(BCH_SB_INODE_32BIT,       struct bch_sb, flags[1],  8,  9);
 
 LE64_BITMASK(BCH_SB_128_BIT_MACS,      struct bch_sb, flags[1],  9, 10);
@@ -1695,7 +980,7 @@ LE64_BITMASK(BCH_SB_PROMOTE_TARGET,        struct bch_sb, flags[1], 28, 40);
 LE64_BITMASK(BCH_SB_FOREGROUND_TARGET, struct bch_sb, flags[1], 40, 52);
 LE64_BITMASK(BCH_SB_BACKGROUND_TARGET, struct bch_sb, flags[1], 52, 64);
 
-LE64_BITMASK(BCH_SB_BACKGROUND_COMPRESSION_TYPE,
+LE64_BITMASK(BCH_SB_BACKGROUND_COMPRESSION_TYPE_LO,
                                        struct bch_sb, flags[2],  0,  4);
 LE64_BITMASK(BCH_SB_GC_RESERVE_BYTES,  struct bch_sb, flags[2],  4, 64);
 
@@ -1709,6 +994,37 @@ LE64_BITMASK(BCH_SB_JOURNAL_RECLAIM_DELAY,struct bch_sb, flags[4], 0, 32);
 LE64_BITMASK(BCH_SB_JOURNAL_TRANSACTION_NAMES,struct bch_sb, flags[4], 32, 33);
 LE64_BITMASK(BCH_SB_NOCOW,             struct bch_sb, flags[4], 33, 34);
 LE64_BITMASK(BCH_SB_WRITE_BUFFER_SIZE, struct bch_sb, flags[4], 34, 54);
+LE64_BITMASK(BCH_SB_VERSION_UPGRADE,   struct bch_sb, flags[4], 54, 56);
+
+LE64_BITMASK(BCH_SB_COMPRESSION_TYPE_HI,struct bch_sb, flags[4], 56, 60);
+LE64_BITMASK(BCH_SB_BACKGROUND_COMPRESSION_TYPE_HI,
+                                       struct bch_sb, flags[4], 60, 64);
+
+LE64_BITMASK(BCH_SB_VERSION_UPGRADE_COMPLETE,
+                                       struct bch_sb, flags[5],  0, 16);
+
+static inline __u64 BCH_SB_COMPRESSION_TYPE(const struct bch_sb *sb)
+{
+       return BCH_SB_COMPRESSION_TYPE_LO(sb) | (BCH_SB_COMPRESSION_TYPE_HI(sb) << 4);
+}
+
+static inline void SET_BCH_SB_COMPRESSION_TYPE(struct bch_sb *sb, __u64 v)
+{
+       SET_BCH_SB_COMPRESSION_TYPE_LO(sb, v);
+       SET_BCH_SB_COMPRESSION_TYPE_HI(sb, v >> 4);
+}
+
+static inline __u64 BCH_SB_BACKGROUND_COMPRESSION_TYPE(const struct bch_sb *sb)
+{
+       return BCH_SB_BACKGROUND_COMPRESSION_TYPE_LO(sb) |
+               (BCH_SB_BACKGROUND_COMPRESSION_TYPE_HI(sb) << 4);
+}
+
+static inline void SET_BCH_SB_BACKGROUND_COMPRESSION_TYPE(struct bch_sb *sb, __u64 v)
+{
+       SET_BCH_SB_BACKGROUND_COMPRESSION_TYPE_LO(sb, v);
+       SET_BCH_SB_BACKGROUND_COMPRESSION_TYPE_HI(sb, v >> 4);
+}
 
 /*
  * Features:
@@ -1776,6 +1092,17 @@ enum bch_sb_compat {
 
 /* options: */
 
+#define BCH_VERSION_UPGRADE_OPTS()     \
+       x(compatible,           0)      \
+       x(incompatible,         1)      \
+       x(none,                 2)
+
+enum bch_version_upgrade_opts {
+#define x(t, n) BCH_VERSION_UPGRADE_##t = n,
+       BCH_VERSION_UPGRADE_OPTS()
+#undef x
+};
+
 #define BCH_REPLICAS_MAX               4U
 
 #define BCH_BKEY_PTRS_MAX              16U
@@ -1834,7 +1161,7 @@ enum bch_csum_type {
        BCH_CSUM_NR
 };
 
-static const unsigned bch_crc_bytes[] = {
+static const __maybe_unused unsigned bch_crc_bytes[] = {
        [BCH_CSUM_none]                         = 0,
        [BCH_CSUM_crc32c_nonzero]               = 4,
        [BCH_CSUM_crc32c]                       = 4,
@@ -1905,11 +1232,11 @@ enum bch_compression_opts {
  */
 
 #define BCACHE_MAGIC                                                   \
-       UUID_LE(0xf67385c6, 0x1a4e, 0xca45,                             \
-               0x82, 0x65, 0xf5, 0x7f, 0x48, 0xba, 0x6d, 0x81)
+       UUID_INIT(0xc68573f6, 0x4e1a, 0x45ca,                           \
+                 0x82, 0x65, 0xf5, 0x7f, 0x48, 0xba, 0x6d, 0x81)
 #define BCHFS_MAGIC                                                    \
-       UUID_LE(0xf67385c6, 0xce66, 0xa990,                             \
-               0xd9, 0x6a, 0x60, 0xcf, 0x80, 0x3d, 0xf7, 0xef)
+       UUID_INIT(0xc68573f6, 0x66ce, 0x90a9,                           \
+                 0xd9, 0x6a, 0x60, 0xcf, 0x80, 0x3d, 0xf7, 0xef)
 
 #define BCACHEFS_STATFS_MAGIC          0xca451a4e
 
@@ -1949,7 +1276,9 @@ static inline __u64 __bset_magic(struct bch_sb *sb)
        x(clock,                7)              \
        x(dev_usage,            8)              \
        x(log,                  9)              \
-       x(overwrite,            10)
+       x(overwrite,            10)             \
+       x(write_buffer_keys,    11)             \
+       x(datetime,             12)
 
 enum {
 #define x(f, nr)       BCH_JSET_ENTRY_##f      = nr,
@@ -1958,6 +1287,19 @@ enum {
        BCH_JSET_ENTRY_NR
 };
 
+static inline bool jset_entry_is_key(struct jset_entry *e)
+{
+       switch (e->type) {
+       case BCH_JSET_ENTRY_btree_keys:
+       case BCH_JSET_ENTRY_btree_root:
+       case BCH_JSET_ENTRY_overwrite:
+       case BCH_JSET_ENTRY_write_buffer_keys:
+               return true;
+       }
+
+       return false;
+}
+
 /*
  * Journal sequence numbers can be blacklisted: bsets record the max sequence
  * number of all the journal entries they contain updates for, so that on
@@ -1999,7 +1341,7 @@ struct jset_entry_usage {
 struct jset_entry_data_usage {
        struct jset_entry       entry;
        __le64                  v;
-       struct bch_replicas_entry r;
+       struct bch_replicas_entry_v1 r;
 } __packed;
 
 struct jset_entry_clock {
@@ -2020,11 +1362,11 @@ struct jset_entry_dev_usage {
        __le32                  dev;
        __u32                   pad;
 
-       __le64                  buckets_ec;
-       __le64                  _buckets_unavailable; /* No longer used */
+       __le64                  _buckets_ec;            /* No longer used */
+       __le64                  _buckets_unavailable;   /* No longer used */
 
        struct jset_entry_dev_usage_type d[];
-} __packed;
+};
 
 static inline unsigned jset_entry_dev_usage_nr_types(struct jset_entry_dev_usage *u)
 {
@@ -2035,7 +1377,12 @@ static inline unsigned jset_entry_dev_usage_nr_types(struct jset_entry_dev_usage
 struct jset_entry_log {
        struct jset_entry       entry;
        u8                      d[];
-} __packed;
+} __packed __aligned(8);
+
+struct jset_entry_datetime {
+       struct jset_entry       entry;
+       __le64                  seconds;
+} __packed __aligned(8);
 
 /*
  * On disk format for a journal entry:
@@ -2066,10 +1413,8 @@ struct jset {
        __le64                  last_seq;
 
 
-       union {
-               struct jset_entry start[0];
-               __u64           _data[0];
-       };
+       struct jset_entry       start[0];
+       __u64                   _data[];
 } __packed __aligned(8);
 
 LE32_BITMASK(JSET_CSUM_TYPE,   struct jset, flags, 0, 4);
@@ -2080,25 +1425,80 @@ LE32_BITMASK(JSET_NO_FLUSH,     struct jset, flags, 5, 6);
 
 /* Btree: */
 
-#define BCH_BTREE_IDS()                                \
-       x(extents,              0)              \
-       x(inodes,               1)              \
-       x(dirents,              2)              \
-       x(xattrs,               3)              \
-       x(alloc,                4)              \
-       x(quotas,               5)              \
-       x(stripes,              6)              \
-       x(reflink,              7)              \
-       x(subvolumes,           8)              \
-       x(snapshots,            9)              \
-       x(lru,                  10)             \
-       x(freespace,            11)             \
-       x(need_discard,         12)             \
-       x(backpointers,         13)             \
-       x(bucket_gens,          14)
+enum btree_id_flags {
+       /* key size field is nonzero, btree iterators handle as ranges  */
+       BTREE_ID_EXTENTS                = BIT(0),
+       BTREE_ID_SNAPSHOTS              = BIT(1),
+       BTREE_ID_SNAPSHOT_FIELD         = BIT(2),
+       BTREE_ID_SNAPSHOTS_UNREFFED     = BIT(3),
+       BTREE_ID_DATA                   = BIT(3),
+};
+
+#define BCH_BTREE_IDS()                                                                \
+       x(extents,              0,      BTREE_ID_EXTENTS|BTREE_ID_SNAPSHOTS|    \
+                                       BTREE_ID_SNAPSHOTS_UNREFFED|BTREE_ID_DATA,\
+         BIT_ULL(KEY_TYPE_whiteout)|                                           \
+         BIT_ULL(KEY_TYPE_error)|                                              \
+         BIT_ULL(KEY_TYPE_cookie)|                                             \
+         BIT_ULL(KEY_TYPE_extent)|                                             \
+         BIT_ULL(KEY_TYPE_reservation)|                                        \
+         BIT_ULL(KEY_TYPE_reflink_p)|                                          \
+         BIT_ULL(KEY_TYPE_inline_data))                                        \
+       x(inodes,               1,      BTREE_ID_SNAPSHOTS,                     \
+         BIT_ULL(KEY_TYPE_whiteout)|                                           \
+         BIT_ULL(KEY_TYPE_inode)|                                              \
+         BIT_ULL(KEY_TYPE_inode_v2)|                                           \
+         BIT_ULL(KEY_TYPE_inode_v3)|                                           \
+         BIT_ULL(KEY_TYPE_inode_generation))                                   \
+       x(dirents,              2,      BTREE_ID_SNAPSHOTS,                     \
+         BIT_ULL(KEY_TYPE_whiteout)|                                           \
+         BIT_ULL(KEY_TYPE_hash_whiteout)|                                      \
+         BIT_ULL(KEY_TYPE_dirent))                                             \
+       x(xattrs,               3,      BTREE_ID_SNAPSHOTS|BTREE_ID_SNAPSHOTS_UNREFFED,\
+         BIT_ULL(KEY_TYPE_whiteout)|                                           \
+         BIT_ULL(KEY_TYPE_cookie)|                                             \
+         BIT_ULL(KEY_TYPE_hash_whiteout)|                                      \
+         BIT_ULL(KEY_TYPE_xattr))                                              \
+       x(alloc,                4,      0,                                      \
+         BIT_ULL(KEY_TYPE_alloc)|                                              \
+         BIT_ULL(KEY_TYPE_alloc_v2)|                                           \
+         BIT_ULL(KEY_TYPE_alloc_v3)|                                           \
+         BIT_ULL(KEY_TYPE_alloc_v4))                                           \
+       x(quotas,               5,      0,                                      \
+         BIT_ULL(KEY_TYPE_quota))                                              \
+       x(stripes,              6,      0,                                      \
+         BIT_ULL(KEY_TYPE_stripe))                                             \
+       x(reflink,              7,      BTREE_ID_EXTENTS|BTREE_ID_DATA,         \
+         BIT_ULL(KEY_TYPE_reflink_v)|                                          \
+         BIT_ULL(KEY_TYPE_indirect_inline_data))                               \
+       x(subvolumes,           8,      0,                                      \
+         BIT_ULL(KEY_TYPE_subvolume))                                          \
+       x(snapshots,            9,      0,                                      \
+         BIT_ULL(KEY_TYPE_snapshot))                                           \
+       x(lru,                  10,     0,                                      \
+         BIT_ULL(KEY_TYPE_set))                                                \
+       x(freespace,            11,     BTREE_ID_EXTENTS,                       \
+         BIT_ULL(KEY_TYPE_set))                                                \
+       x(need_discard,         12,     0,                                      \
+         BIT_ULL(KEY_TYPE_set))                                                \
+       x(backpointers,         13,     0,                                      \
+         BIT_ULL(KEY_TYPE_backpointer))                                        \
+       x(bucket_gens,          14,     0,                                      \
+         BIT_ULL(KEY_TYPE_bucket_gens))                                        \
+       x(snapshot_trees,       15,     0,                                      \
+         BIT_ULL(KEY_TYPE_snapshot_tree))                                      \
+       x(deleted_inodes,       16,     BTREE_ID_SNAPSHOT_FIELD,                \
+         BIT_ULL(KEY_TYPE_set))                                                \
+       x(logged_ops,           17,     0,                                      \
+         BIT_ULL(KEY_TYPE_logged_op_truncate)|                                 \
+         BIT_ULL(KEY_TYPE_logged_op_finsert))                                  \
+       x(rebalance_work,       18,     BTREE_ID_SNAPSHOT_FIELD,                \
+         BIT_ULL(KEY_TYPE_set)|BIT_ULL(KEY_TYPE_cookie))                       \
+       x(subvolume_children,   19,     0,                                      \
+         BIT_ULL(KEY_TYPE_set))
 
 enum btree_id {
-#define x(kwd, val) BTREE_ID_##kwd = val,
+#define x(name, nr, ...) BTREE_ID_##name = nr,
        BCH_BTREE_IDS()
 #undef x
        BTREE_ID_NR
@@ -2130,10 +1530,8 @@ struct bset {
        __le16                  version;
        __le16                  u64s; /* count of d[] in u64s */
 
-       union {
-               struct bkey_packed start[0];
-               __u64           _data[0];
-       };
+       struct bkey_packed      start[0];
+       __u64                   _data[];
 } __packed __aligned(8);
 
 LE32_BITMASK(BSET_CSUM_TYPE,   struct bset, flags, 0, 4);
@@ -2169,13 +1567,25 @@ struct btree_node {
        };
 } __packed __aligned(8);
 
-LE64_BITMASK(BTREE_NODE_ID,    struct btree_node, flags,  0,  4);
+LE64_BITMASK(BTREE_NODE_ID_LO, struct btree_node, flags,  0,  4);
 LE64_BITMASK(BTREE_NODE_LEVEL, struct btree_node, flags,  4,  8);
 LE64_BITMASK(BTREE_NODE_NEW_EXTENT_OVERWRITE,
                                struct btree_node, flags,  8,  9);
-/* 9-32 unused */
+LE64_BITMASK(BTREE_NODE_ID_HI, struct btree_node, flags,  9, 25);
+/* 25-32 unused */
 LE64_BITMASK(BTREE_NODE_SEQ,   struct btree_node, flags, 32, 64);
 
+static inline __u64 BTREE_NODE_ID(struct btree_node *n)
+{
+       return BTREE_NODE_ID_LO(n) | (BTREE_NODE_ID_HI(n) << 4);
+}
+
+static inline void SET_BTREE_NODE_ID(struct btree_node *n, __u64 v)
+{
+       SET_BTREE_NODE_ID_LO(n, v);
+       SET_BTREE_NODE_ID_HI(n, v >> 4);
+}
+
 struct btree_node_entry {
        struct bch_csum         csum;
 
@@ -2185,7 +1595,6 @@ struct btree_node_entry {
                __u8            pad[22];
                __le16          u64s;
                __u64           _data[0];
-
        };
        };
 } __packed __aligned(8);