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package btrfs
import (
"fmt"
"lukeshu.com/btrfs-tools/pkg/binstruct"
)
type ItemType uint8
const (
BTRFS_UNTYPED_KEY = ItemType(0)
// inode items have the data typically returned from stat and store other
// info about object characteristics. There is one for every file and dir in
// the FS
BTRFS_INODE_ITEM_KEY = ItemType(1)
BTRFS_INODE_REF_KEY = ItemType(12)
BTRFS_INODE_EXTREF_KEY = ItemType(13)
BTRFS_XATTR_ITEM_KEY = ItemType(24)
BTRFS_VERITY_DESC_ITEM_KEY = ItemType(36) // new
BTRFS_VERITY_MERKLE_ITEM_KEY = ItemType(37) // new
BTRFS_ORPHAN_ITEM_KEY = ItemType(48)
BTRFS_DIR_LOG_ITEM_KEY = ItemType(60)
BTRFS_DIR_LOG_INDEX_KEY = ItemType(72)
// dir items are the name -> inode pointers in a directory. There is one
// for every name in a directory.
BTRFS_DIR_ITEM_KEY = ItemType(84)
BTRFS_DIR_INDEX_KEY = ItemType(96)
// extent data is for file data
BTRFS_EXTENT_DATA_KEY = ItemType(108)
// csum items have the checksums for data in the extents
BTRFS_CSUM_ITEM_KEY = ItemType(120) // new
// extent csums are stored in a separate tree and hold csums for
// an entire extent on disk.
BTRFS_EXTENT_CSUM_KEY = ItemType(128)
// root items point to tree roots. There are typically in the root
// tree used by the super block to find all the other trees
BTRFS_ROOT_ITEM_KEY = ItemType(132)
// root backrefs tie subvols and snapshots to the directory entries that
// reference them
BTRFS_ROOT_BACKREF_KEY = ItemType(144)
// root refs make a fast index for listing all of the snapshots and
// subvolumes referenced by a given root. They point directly to the
// directory item in the root that references the subvol
BTRFS_ROOT_REF_KEY = ItemType(156)
// extent items are in the extent map tree. These record which blocks
// are used, and how many references there are to each block
BTRFS_EXTENT_ITEM_KEY = ItemType(168)
// The same as the BTRFS_EXTENT_ITEM_KEY, except it's metadata we already know
// the length, so we save the level in key->offset instead of the length.
BTRFS_METADATA_ITEM_KEY = ItemType(169) // new
BTRFS_TREE_BLOCK_REF_KEY = ItemType(176)
BTRFS_EXTENT_DATA_REF_KEY = ItemType(178)
// old style extent backrefs
BTRFS_EXTENT_REF_V0_KEY = ItemType(180)
BTRFS_SHARED_BLOCK_REF_KEY = ItemType(182)
BTRFS_SHARED_DATA_REF_KEY = ItemType(184)
// block groups give us hints into the extent allocation trees. Which
// blocks are free etc etc
BTRFS_BLOCK_GROUP_ITEM_KEY = ItemType(192)
// Every block group is represented in the free space tree by a free space info
// item, which stores some accounting information. It is keyed on
// (block_group_start, FREE_SPACE_INFO, block_group_length).
BTRFS_FREE_SPACE_INFO_KEY = ItemType(198) // new
// A free space extent tracks an extent of space that is free in a block group.
// It is keyed on (start, FREE_SPACE_EXTENT, length).
BTRFS_FREE_SPACE_EXTENT_KEY = ItemType(199) // new
// When a block group becomes very fragmented, we convert it to use bitmaps
// instead of extents. A free space bitmap is keyed on
// (start, FREE_SPACE_BITMAP, length); the corresponding item is a bitmap with
// (length / sectorsize) bits.
BTRFS_FREE_SPACE_BITMAP_KEY = ItemType(200) // new
BTRFS_DEV_EXTENT_KEY = ItemType(204)
BTRFS_DEV_ITEM_KEY = ItemType(216)
BTRFS_CHUNK_ITEM_KEY = ItemType(228)
// quota groups
BTRFS_QGROUP_STATUS_KEY = ItemType(240) // new
BTRFS_QGROUP_INFO_KEY = ItemType(242) // new
BTRFS_QGROUP_LIMIT_KEY = ItemType(244) // new
BTRFS_QGROUP_RELATION_KEY = ItemType(246) // new
// The key type for tree items that are stored persistently, but do not need to
// exist for extended period of time. The items can exist in any tree.
//
// [subtype, BTRFS_TEMPORARY_ITEM_KEY, data]
//
// Existing items:
//
// - balance status item
// (BTRFS_BALANCE_OBJECTID, BTRFS_TEMPORARY_ITEM_KEY, 0)
BTRFS_TEMPORARY_ITEM_KEY = ItemType(248) // new
// The key type for tree items that are stored persistently and usually exist
// for a long period, eg. filesystem lifetime. The item kinds can be status
// information, stats or preference values. The item can exist in any tree.
//
// [subtype, BTRFS_PERSISTENT_ITEM_KEY, data]
//
// Existing items:
//
// - device statistics, store IO stats in the device tree, one key for all
// stats
// (BTRFS_DEV_STATS_OBJECTID, BTRFS_DEV_STATS_KEY, 0)
BTRFS_PERSISTENT_ITEM_KEY = ItemType(249) // new
// Persistently stores the device replace state in the device tree.
// The key is built like this: (0, BTRFS_DEV_REPLACE_KEY, 0).
BTRFS_DEV_REPLACE_KEY = ItemType(250)
// Stores items that allow to quickly map UUIDs to something else.
// These items are part of the filesystem UUID tree.
// The key is built like this:
// (UUID_upper_64_bits, BTRFS_UUID_KEY*, UUID_lower_64_bits).
BTRFS_UUID_KEY_SUBVOL = ItemType(251) // for UUIDs assigned to subvols // new
BTRFS_UUID_KEY_RECEIVED_SUBVOL = ItemType(252) // for UUIDs assigned to received subvols // new
// string items are for debugging. They just store a short string of
// data in the FS
BTRFS_STRING_ITEM_KEY = ItemType(253)
)
func (t ItemType) String() string {
names := map[ItemType]string{
BTRFS_UNTYPED_KEY: "UNTYPED",
BTRFS_INODE_ITEM_KEY: "INODE_ITEM",
BTRFS_INODE_REF_KEY: "INODE_REF",
BTRFS_INODE_EXTREF_KEY: "INODE_EXTREF",
BTRFS_XATTR_ITEM_KEY: "XATTR_ITEM",
BTRFS_VERITY_DESC_ITEM_KEY: "VERITY_DESC_ITEM",
BTRFS_VERITY_MERKLE_ITEM_KEY: "VERITY_MERKLE_ITEM",
BTRFS_ORPHAN_ITEM_KEY: "ORPHAN_ITEM",
BTRFS_DIR_LOG_ITEM_KEY: "DIR_LOG_ITEM",
BTRFS_DIR_LOG_INDEX_KEY: "DIR_LOG_INDEX",
BTRFS_DIR_ITEM_KEY: "DIR_ITEM",
BTRFS_DIR_INDEX_KEY: "DIR_INDEX",
BTRFS_EXTENT_DATA_KEY: "EXTENT_DATA",
BTRFS_CSUM_ITEM_KEY: "CSUM_ITEM",
BTRFS_EXTENT_CSUM_KEY: "EXTENT_CSUM",
BTRFS_ROOT_ITEM_KEY: "ROOT_ITEM",
BTRFS_ROOT_BACKREF_KEY: "ROOT_BACKREF",
BTRFS_ROOT_REF_KEY: "ROOT_REF",
BTRFS_EXTENT_ITEM_KEY: "EXTENT_ITEM",
BTRFS_METADATA_ITEM_KEY: "METADATA_ITEM",
BTRFS_TREE_BLOCK_REF_KEY: "TREE_BLOCK_REF",
BTRFS_EXTENT_DATA_REF_KEY: "EXTENT_DATA_REF",
BTRFS_EXTENT_REF_V0_KEY: "EXTENT_REF_V0",
BTRFS_SHARED_BLOCK_REF_KEY: "SHARED_BLOCK_REF",
BTRFS_SHARED_DATA_REF_KEY: "SHARED_DATA_REF",
BTRFS_BLOCK_GROUP_ITEM_KEY: "BLOCK_GROUP_ITEM",
BTRFS_FREE_SPACE_INFO_KEY: "FREE_SPACE_INFO",
BTRFS_FREE_SPACE_EXTENT_KEY: "FREE_SPACE_EXTENT",
BTRFS_FREE_SPACE_BITMAP_KEY: "FREE_SPACE_BITMAP",
BTRFS_DEV_EXTENT_KEY: "DEV_EXTENT",
BTRFS_DEV_ITEM_KEY: "DEV_ITEM",
BTRFS_CHUNK_ITEM_KEY: "CHUNK_ITEM",
BTRFS_QGROUP_STATUS_KEY: "QGROUP_STATUS",
BTRFS_QGROUP_INFO_KEY: "QGROUP_INFO",
BTRFS_QGROUP_LIMIT_KEY: "QGROUP_LIMIT",
BTRFS_QGROUP_RELATION_KEY: "QGROUP_RELATION",
BTRFS_TEMPORARY_ITEM_KEY: "TEMPORARY_ITEM",
BTRFS_PERSISTENT_ITEM_KEY: "PERSISTENT_ITEM",
BTRFS_DEV_REPLACE_KEY: "DEV_REPLACE",
BTRFS_UUID_KEY_SUBVOL: "UUID_KEY_SUBVOL",
BTRFS_UUID_KEY_RECEIVED_SUBVOL: "UUID_KEY_RECEIVED_SUBVOL",
BTRFS_STRING_ITEM_KEY: "STRING_ITEM",
}
if name, ok := names[t]; ok {
return name
}
return fmt.Sprintf("%d", t)
}
type DevItem struct {
DeviceID ObjID `bin:"off=0, siz=8"` // device ID
NumBytes uint64 `bin:"off=8, siz=8"` // number of bytes
NumBytesUsed uint64 `bin:"off=10, siz=8"` // number of bytes used
IOOptimalAlign uint32 `bin:"off=18, siz=4"` // optimal I/O align
IOOptimalWidth uint32 `bin:"off=1c, siz=4"` // optimal I/O width
IOMinSize uint32 `bin:"off=20, siz=4"` // minimal I/O size (sector size)
Type uint64 `bin:"off=24, siz=8"` // type
Generation Generation `bin:"off=2c, siz=8"` // generation
StartOffset uint64 `bin:"off=34, siz=8"` // start offset
DevGroup uint32 `bin:"off=3c, siz=4"` // dev group
SeekSpeed uint8 `bin:"off=40, siz=1"` // seek speed
Bandwidth uint8 `bin:"off=41, siz=1"` // bandwidth
DevUUID UUID `bin:"off=42, siz=10"` // device UUID
FSUUID UUID `bin:"off=52, siz=10"` // FS UUID
binstruct.End `bin:"off=62"`
}
type InodeRefItem struct {
Index int64 `bin:"off=0, siz=8"`
NameLen int16 `bin:"off=8, siz=2"`
binstruct.End `bin:"off=a"`
Name []byte `bin:"-"`
}
type InodeItem struct {
Generation int64 `bin:"off=0, siz=8"`
TransID int64 `bin:"off=8, siz=8"`
Size int64 `bin:"off=10, siz=8"`
NumBytes int64 `bin:"off=18, siz=8"`
BlockGroup int64 `bin:"off=20, siz=8"`
NLink int32 `bin:"off=28, siz=4"`
UID int32 `bin:"off=2C, siz=4"`
GID int32 `bin:"off=30, siz=4"`
Mode int32 `bin:"off=34, siz=4"`
RDev int64 `bin:"off=38, siz=8"`
Flags uint64 `bin:"off=40, siz=8"`
Sequence int64 `bin:"off=48, siz=8"`
Reserved [4]int64 `bin:"off=50, siz=20"`
ATime Time `bin:"off=70, siz=c"`
CTime Time `bin:"off=7c, siz=c"`
MTime Time `bin:"off=88, siz=c"`
OTime Time `bin:"off=94, siz=c"`
binstruct.End `bin:"off=a0"`
}
type RootItem struct {
Inode InodeItem `bin:"off=0, siz=a0"`
Generation int64 `bin:"off=a0, siz=8"`
RootDirID int64 `bin:"off=a8, siz=8"`
ByteNr LogicalAddr `bin:"off=b0, siz=8"`
ByteLimit int64 `bin:"off=b8, siz=8"`
BytesUsed int64 `bin:"off=c0, siz=8"`
LastSnapshot int64 `bin:"off=c8, siz=8"`
Flags RootItemFlags `bin:"off=d0, siz=8"`
Refs int32 `bin:"off=d8, siz=4"`
DropProgress Key `bin:"off=dc, siz=11"`
DropLevel uint8 `bin:"off=ed, siz=1"`
Level uint8 `bin:"off=ee, siz=1"`
GenerationV2 int64 `bin:"off=ef, siz=8"`
UUID UUID `bin:"off=F7, siz=10"`
ParentUUID UUID `bin:"off=107, siz=10"`
ReceivedUUID UUID `bin:"off=117, siz=10"`
CTransID int64 `bin:"off=127, siz=8"`
OTransID int64 `bin:"off=12f, siz=8"`
STransID int64 `bin:"off=137, siz=8"`
RTransID int64 `bin:"off=13f, siz=8"`
CTime Time `bin:"off=147, siz=c"`
OTime Time `bin:"off=153, siz=c"`
STime Time `bin:"off=15F, siz=c"`
RTime Time `bin:"off=16b, siz=c"`
GlobalTreeID ObjID `bin:"off=177, siz=8"`
Reserved [7]int64 `bin:"off=17f, siz=38"`
binstruct.End `bin:"off=1b7"`
}
|
