update main, kinda

19 files changed, 197 insertions, 353 deletions

diff --git a/cmd/btrfs-dump-tree/main.go b/cmd/btrfs-dump-tree/main.go
index ca9d527..d5aa94e 100644
--- a/cmd/btrfs-dump-tree/main.go
+++ b/cmd/btrfs-dump-tree/main.go
@@ -7,6 +7,8 @@ import (
 
 	"lukeshu.com/btrfs-tools/pkg/binstruct"
 	"lukeshu.com/btrfs-tools/pkg/btrfs"
+	"lukeshu.com/btrfs-tools/pkg/btrfs/btrfsitem"
+	"lukeshu.com/btrfs-tools/pkg/util"
 )
 
 func main() {
@@ -72,64 +74,68 @@ func Main(imgfilename string) (err error) {
 
 // printTree mimics btrfs-progs kernel-shared/print-tree.c:btrfs_print_tree() and  kernel-shared/print-tree.c:btrfs_print_leaf()
 func printTree(fs *btrfs.FS, root btrfs.LogicalAddr) {
-	node, err := fs.ReadNode(root)
+	nodeRef, err := fs.ReadNode(root)
 	if err != nil {
 		fmt.Printf("error: %v\n", err)
 		return
 	}
+	node := nodeRef.Data
 	printHeaderInfo(node)
-	switch node := node.(type) {
-	case *btrfs.InternalNode:
-		for _, item := range node.Body {
+	if node.Head.Level > 0 { // internal
+		for _, item := range node.BodyInternal {
 			fmt.Printf("\t%s block %d gen %d\n",
-				fmtKey(item.Data.Key),
-				item.Data.BlockPtr,
-				item.Data.Generation)
+				fmtKey(item.Key),
+				item.BlockPtr,
+				item.Generation)
 		}
-		for _, item := range node.Body {
-			printTree(fs, item.Data.BlockPtr)
+		for _, item := range node.BodyInternal {
+			printTree(fs, item.BlockPtr)
 		}
-	case *btrfs.LeafNode:
-		for i, item := range node.Body {
+	} else { // leaf
+		for i, item := range node.BodyLeaf {
 			fmt.Printf("\titem %d %s itemoff %d itemsize %d\n",
 				i,
-				fmtKey(item.Data.Key),
-				item.Data.DataOffset,
-				item.Data.DataSize)
-			switch item.Data.Key.ItemType {
-			case btrfs.BTRFS_UNTYPED_KEY:
-				// TODO
-			case btrfs.BTRFS_INODE_ITEM_KEY:
-				// TODO(!)
-			case btrfs.BTRFS_INODE_REF_KEY:
-				dat := item.Data.Data.Data
+				fmtKey(item.Head.Key),
+				item.Head.DataOffset,
+				item.Head.DataSize)
+			switch item.Head.Key.ItemType {
+			//case btrfsitem.UNTYPED_KEY:
+			//	// TODO
+			//case btrfsitem.INODE_ITEM_KEY:
+			//	// TODO(!)
+			case btrfsitem.INODE_REF_KEY:
+				dat := item.Body
 				for len(dat) > 0 {
-					var ref btrfs.InodeRefItem
-					if err := binstruct.Unmarshal(dat, &ref); err != nil {
+					var ref btrfsitem.InodeRef
+					n, err := binstruct.Unmarshal(dat, &ref)
+					if err != nil {
 						fmt.Printf("error: %v\n", err)
 						return
 					}
-					dat = dat[0xA:]
-					ref.Name = dat[:ref.NameLen]
-					dat = dat[ref.NameLen:]
-
 					fmt.Printf("\t\tindex %d namelen %d name: %s\n",
 						ref.Index, ref.NameLen, ref.Name)
+					dat = dat[n:]
 				}
-			case btrfs.BTRFS_INODE_EXTREF_KEY:
-				// TODO
-			case btrfs.BTRFS_DIR_ITEM_KEY, btrfs.BTRFS_DIR_INDEX_KEY, btrfs.BTRFS_XATTR_ITEM_KEY:
-				// TODO
-			case btrfs.BTRFS_DIR_LOG_INDEX_KEY, btrfs.BTRFS_DIR_LOG_ITEM_KEY:
-				// TODO
-			case btrfs.BTRFS_ORPHAN_ITEM_KEY:
+			//case btrfsitem.INODE_EXTREF_KEY:
+			//	// TODO
+			//case btrfsitem.DIR_ITEM_KEY, btrfsitem.DIR_INDEX_KEY, btrfsitem.XATTR_ITEM_KEY:
+			//	// TODO
+			//case btrfsitem.DIR_LOG_INDEX_KEY, btrfsitem.DIR_LOG_ITEM_KEY:
+			//	// TODO
+			case btrfsitem.ORPHAN_ITEM_KEY:
 				fmt.Printf("\t\torphan item\n")
-			case btrfs.BTRFS_ROOT_ITEM_KEY:
-				var obj btrfs.RootItem
-				if err := binstruct.Unmarshal(item.Data.Data.Data, &obj); err != nil {
+			case btrfsitem.ROOT_ITEM_KEY:
+				var obj btrfsitem.Root
+				n, err := binstruct.Unmarshal(item.Body, &obj)
+				if err != nil {
 					fmt.Printf("error: %v\n", err)
 					return
 				}
+				if n != len(item.Body) {
+					fmt.Printf("error: left over data: got %d bytes but only consumed %d\n", len(item.Body), n)
+					return
+				}
+
 				fmt.Printf("\t\tgeneration %d root_dirid %d bytenr %d byte_limit %d bytes_used %d\n",
 					obj.Generation, obj.RootDirID, obj.ByteNr, obj.ByteLimit, obj.BytesUsed)
 				fmt.Printf("\t\tlast_snapshot %d flags %s refs %d\n",
@@ -149,58 +155,58 @@ func printTree(fs *btrfs.FS, root btrfs.LogicalAddr) {
 					fmt.Printf("\t\tstime %s\n", fmtTime(obj.STime))
 					fmt.Printf("\t\trtime %s\n", fmtTime(obj.RTime))
 				}
-			case btrfs.BTRFS_ROOT_REF_KEY:
-				// TODO
-			case btrfs.BTRFS_ROOT_BACKREF_KEY:
-				// TODO
-			case btrfs.BTRFS_EXTENT_ITEM_KEY:
-				// TODO
-			case btrfs.BTRFS_METADATA_ITEM_KEY:
-				// TODO
-			case btrfs.BTRFS_TREE_BLOCK_REF_KEY:
+			//case btrfsitem.ROOT_REF_KEY:
+			//	// TODO
+			//case btrfsitem.ROOT_BACKREF_KEY:
+			//	// TODO
+			//case btrfsitem.EXTENT_ITEM_KEY:
+			//	// TODO
+			//case btrfsitem.METADATA_ITEM_KEY:
+			//	// TODO
+			case btrfsitem.TREE_BLOCK_REF_KEY:
 				fmt.Printf("\t\ttree block backref\n")
-			case btrfs.BTRFS_SHARED_BLOCK_REF_KEY:
+			case btrfsitem.SHARED_BLOCK_REF_KEY:
 				fmt.Printf("\t\tshared block backref\n")
-			case btrfs.BTRFS_EXTENT_DATA_REF_KEY:
-				// TODO
-			case btrfs.BTRFS_SHARED_DATA_REF_KEY:
-				// TODO
-			case btrfs.BTRFS_EXTENT_REF_V0_KEY:
+			//case btrfsitem.EXTENT_DATA_REF_KEY:
+			//	// TODO
+			//case btrfsitem.SHARED_DATA_REF_KEY:
+			//	// TODO
+			case btrfsitem.EXTENT_REF_V0_KEY:
 				fmt.Printf("\t\textent ref v0 (deprecated)\n")
-			case btrfs.BTRFS_CSUM_ITEM_KEY:
+			case btrfsitem.CSUM_ITEM_KEY:
 				fmt.Printf("\t\tcsum item\n")
-			case btrfs.BTRFS_EXTENT_CSUM_KEY:
-				// TODO
-			case btrfs.BTRFS_EXTENT_DATA_KEY:
-				// TODO
-			case btrfs.BTRFS_BLOCK_GROUP_ITEM_KEY:
-				// TODO
-			case btrfs.BTRFS_FREE_SPACE_INFO_KEY:
-				// TODO
-			case btrfs.BTRFS_FREE_SPACE_EXTENT_KEY:
+			//case btrfsitem.EXTENT_CSUM_KEY:
+			//	// TODO
+			//case btrfsitem.EXTENT_DATA_KEY:
+			//	// TODO
+			//case btrfsitem.BLOCK_GROUP_ITEM_KEY:
+			//	// TODO
+			//case btrfsitem.FREE_SPACE_INFO_KEY:
+			//	// TODO
+			case btrfsitem.FREE_SPACE_EXTENT_KEY:
 				fmt.Printf("\t\tfree space extent\n")
-			case btrfs.BTRFS_FREE_SPACE_BITMAP_KEY:
+			case btrfsitem.FREE_SPACE_BITMAP_KEY:
 				fmt.Printf("\t\tfree space bitmap\n")
-			case btrfs.BTRFS_CHUNK_ITEM_KEY:
-				// TODO(!)
-			case btrfs.BTRFS_DEV_ITEM_KEY:
-				// TODO
-			case btrfs.BTRFS_DEV_EXTENT_KEY:
-				// TODO
-			case btrfs.BTRFS_QGROUP_STATUS_KEY:
-				// TODO
-			case btrfs.BTRFS_QGROUP_RELATION_KEY, btrfs.BTRFS_QGROUP_INFO_KEY:
-				// TODO
-			case btrfs.BTRFS_QGROUP_LIMIT_KEY:
-				// TODO
-			case btrfs.BTRFS_UUID_KEY_SUBVOL, btrfs.BTRFS_UUID_KEY_RECEIVED_SUBVOL:
-				// TODO
-			case btrfs.BTRFS_STRING_ITEM_KEY:
-				// TODO
-			case btrfs.BTRFS_PERSISTENT_ITEM_KEY:
-				// TODO
-			case btrfs.BTRFS_TEMPORARY_ITEM_KEY:
-				// TODO
+				//case btrfsitem.CHUNK_ITEM_KEY:
+				//	// TODO(!)
+				//case btrfsitem.DEV_ITEM_KEY:
+				//	// TODO
+				//case btrfsitem.DEV_EXTENT_KEY:
+				//	// TODO
+				//case btrfsitem.QGROUP_STATUS_KEY:
+				//	// TODO
+				//case btrfsitem.QGROUP_RELATION_KEY, btrfsitem.QGROUP_INFO_KEY:
+				//	// TODO
+				//case btrfsitem.QGROUP_LIMIT_KEY:
+				//	// TODO
+				//case btrfsitem.UUID_KEY_SUBVOL, btrfsitem.UUID_KEY_RECEIVED_SUBVOL:
+				//	// TODO
+				//case btrfsitem.STRING_ITEM_KEY:
+				//	// TODO
+				//case btrfsitem.PERSISTENT_ITEM_KEY:
+				//	// TODO
+				//case btrfsitem.TEMPORARY_ITEM_KEY:
+				//	// TODO
 			}
 		}
 	}
@@ -209,36 +215,35 @@ func printTree(fs *btrfs.FS, root btrfs.LogicalAddr) {
 // printHeaderInfo mimics btrfs-progs kernel-shared/print-tree.c:print_header_info()
 func printHeaderInfo(node btrfs.Node) {
 	var typename string
-	switch node := node.(type) {
-	case *btrfs.InternalNode:
+	if node.Head.Level > 0 { // internal node
 		typename = "node"
 		fmt.Printf("node %d level %d items %d free space %d",
-			node.Header.Addr,
-			node.Header.Data.Level,
-			node.Header.Data.NumItems,
-			node.Header.Data.MaxItems-node.Header.Data.NumItems)
-	case *btrfs.LeafNode:
+			node.Head.Addr,
+			node.Head.Level,
+			node.Head.NumItems,
+			node.MaxItems()-node.Head.NumItems)
+	} else { // leaf node
 		typename = "leaf"
 		fmt.Printf("leaf %d items %d free space %d",
-			node.Header.Addr,
-			node.Header.Data.NumItems,
-			node.FreeSpace())
+			node.Head.Addr,
+			node.Head.NumItems,
+			node.LeafFreeSpace())
 	}
 	fmt.Printf(" generation %d owner %v\n",
-		node.GetNodeHeader().Data.Generation,
-		node.GetNodeHeader().Data.Owner)
+		node.Head.Generation,
+		node.Head.Owner)
 
 	fmt.Printf("%s %d flags %s backref revision %d\n",
 		typename,
-		node.GetNodeHeader().Addr,
-		node.GetNodeHeader().Data.Flags,
-		node.GetNodeHeader().Data.BackrefRev)
+		node.Head.Addr,
+		node.Head.Flags,
+		node.Head.BackrefRev)
 
-	fmt.Printf("checksum stored %x\n", node.GetNodeHeader().Data.Checksum)
+	fmt.Printf("checksum stored %x\n", node.Head.Checksum)
 	fmt.Printf("checksum calced %v\n", "TODO")
 
-	fmt.Printf("fs uuid %s\n", node.GetNodeHeader().Data.MetadataUUID)
-	fmt.Printf("chunk uuid %s\n", node.GetNodeHeader().Data.ChunkTreeUUID)
+	fmt.Printf("fs uuid %s\n", node.Head.MetadataUUID)
+	fmt.Printf("chunk uuid %s\n", node.Head.ChunkTreeUUID)
 }
 
 // mimics print-tree.c:btrfs_print_key()
@@ -246,14 +251,14 @@ func fmtKey(key btrfs.Key) string {
 	var out strings.Builder
 	fmt.Fprintf(&out, "key (%s %v", key.ObjectID.Format(key.ItemType), key.ItemType)
 	switch key.ItemType {
-	case btrfs.BTRFS_QGROUP_RELATION_KEY, btrfs.BTRFS_QGROUP_INFO_KEY, btrfs.BTRFS_QGROUP_LIMIT_KEY:
+	case btrfsitem.QGROUP_RELATION_KEY, btrfsitem.QGROUP_INFO_KEY, btrfsitem.QGROUP_LIMIT_KEY:
 		panic("not implemented")
-	case btrfs.BTRFS_UUID_KEY_SUBVOL, btrfs.BTRFS_UUID_KEY_RECEIVED_SUBVOL:
+	case btrfsitem.UUID_KEY_SUBVOL, btrfsitem.UUID_KEY_RECEIVED_SUBVOL:
 		fmt.Fprintf(&out, " 0x%016x)", key.Offset)
-	case btrfs.BTRFS_ROOT_ITEM_KEY:
+	case btrfsitem.ROOT_ITEM_KEY:
 		fmt.Fprintf(&out, " %v)", btrfs.ObjID(key.Offset))
 	default:
-		if key.Offset == btrfs.MaxUint64pp-1 {
+		if key.Offset == util.MaxUint64pp-1 {
 			fmt.Fprintf(&out, " -1)")
 		} else {
 			fmt.Fprintf(&out, " %d)", key.Offset)
diff --git a/pkg/btrfs/Makefile b/pkg/btrfs/Makefile
index cf3a911..781eb7c 100644
--- a/pkg/btrfs/Makefile
+++ b/pkg/btrfs/Makefile
@@ -2,8 +2,6 @@
 .SECONDARY:
 .DELETE_ON_ERROR:
 
-internal:
-	mkdir $@
 btrfsitem/items.txt: btrfsitem $(wildcard btrfsitem/item_*.go) $(MAKEFILE_LIST)
 	sed -En 's,^type (\S+) .* // (.*=.*),\1 \2,p' $(filter btrfsitem/item_%.go,$^) | while read -r typ keys; do for key in $$keys; do echo "$$key" "$$typ"; done; done >$@
 files += btrfsitem/items.txt
diff --git a/pkg/btrfs/btrfsitem/item_chunk.go b/pkg/btrfs/btrfsitem/item_chunk.go
index 41706c3..17f069c 100644
--- a/pkg/btrfs/btrfsitem/item_chunk.go
+++ b/pkg/btrfs/btrfsitem/item_chunk.go
@@ -2,13 +2,13 @@ package btrfsitem
 
 import (
 	"lukeshu.com/btrfs-tools/pkg/binstruct"
-	"lukeshu.com/btrfs-tools/pkg/btrfs/btrfstyp"
+	"lukeshu.com/btrfs-tools/pkg/btrfs/internal"
 )
 
 type Chunk struct { // CHUNK_ITEM=228
 	// Maps logical address to physical.
 	Size           uint64         `bin:"off=0x0,  siz=0x8"` // size of chunk (bytes)
-	Owner          btrfstyp.ObjID `bin:"off=0x8,  siz=0x8"` // root referencing this chunk (2)
+	Owner          internal.ObjID `bin:"off=0x8,  siz=0x8"` // root referencing this chunk (2)
 	StripeLen      uint64         `bin:"off=0x10, siz=0x8"` // stripe length
 	Type           uint64         `bin:"off=0x18, siz=0x8"` // type (same as flags for block group?)
 	IOOptimalAlign uint32         `bin:"off=0x20, siz=0x4"` // optimal io alignment
@@ -22,9 +22,9 @@ type Chunk struct { // CHUNK_ITEM=228
 
 type ChunkStripe struct {
 	// Stripes follow (for each number of stripes):
-	DeviceID      btrfstyp.ObjID `bin:"off=0,  siz=8"`  // device ID
+	DeviceID      internal.ObjID `bin:"off=0,  siz=8"`  // device ID
 	Offset        uint64         `bin:"off=8,  siz=8"`  // offset
-	DeviceUUID    btrfstyp.UUID  `bin:"off=10, siz=10"` // device UUID
+	DeviceUUID    internal.UUID  `bin:"off=10, siz=10"` // device UUID
 	binstruct.End `bin:"off=20"`
 }
 
diff --git a/pkg/btrfs/btrfsitem/item_dev.go b/pkg/btrfs/btrfsitem/item_dev.go
index f474156..fea34d5 100644
--- a/pkg/btrfs/btrfsitem/item_dev.go
+++ b/pkg/btrfs/btrfsitem/item_dev.go
@@ -2,11 +2,11 @@ package btrfsitem
 
 import (
 	"lukeshu.com/btrfs-tools/pkg/binstruct"
-	"lukeshu.com/btrfs-tools/pkg/btrfs/btrfstyp"
+	"lukeshu.com/btrfs-tools/pkg/btrfs/internal"
 )
 
 type Dev struct { // DEV_ITEM=216
-	DeviceID btrfstyp.ObjID `bin:"off=0x0,    siz=0x8"` // device ID
+	DeviceID internal.ObjID `bin:"off=0x0,    siz=0x8"` // device ID
 
 	NumBytes     uint64 `bin:"off=0x8,    siz=0x8"` // number of bytes
 	NumBytesUsed uint64 `bin:"off=0x10,   siz=0x8"` // number of bytes used
@@ -16,14 +16,14 @@ type Dev struct { // DEV_ITEM=216
 	IOMinSize      uint32 `bin:"off=0x20,   siz=0x4"` // minimal I/O size (sector size)
 
 	Type        uint64              `bin:"off=0x24,   siz=0x8"` // type
-	Generation  btrfstyp.Generation `bin:"off=0x2c,   siz=0x8"` // generation
+	Generation  internal.Generation `bin:"off=0x2c,   siz=0x8"` // generation
 	StartOffset uint64              `bin:"off=0x34,   siz=0x8"` // start offset
 	DevGroup    uint32              `bin:"off=0x3c,   siz=0x4"` // dev group
 	SeekSpeed   uint8               `bin:"off=0x40,   siz=0x1"` // seek speed
 	Bandwidth   uint8               `bin:"off=0x41,   siz=0x1"` // bandwidth
 
-	DevUUID btrfstyp.UUID `bin:"off=0x42,   siz=0x10"` // device UUID
-	FSUUID  btrfstyp.UUID `bin:"off=0x52,   siz=0x10"` // FS UUID
+	DevUUID internal.UUID `bin:"off=0x42,   siz=0x10"` // device UUID
+	FSUUID  internal.UUID `bin:"off=0x52,   siz=0x10"` // FS UUID
 
 	binstruct.End `bin:"off=0x62"`
 }
diff --git a/pkg/btrfs/btrfsitem/item_devextent.go b/pkg/btrfs/btrfsitem/item_devextent.go
index 4bdd1c3..fbfa6fb 100644
--- a/pkg/btrfs/btrfsitem/item_devextent.go
+++ b/pkg/btrfs/btrfsitem/item_devextent.go
@@ -2,14 +2,14 @@ package btrfsitem
 
 import (
 	"lukeshu.com/btrfs-tools/pkg/binstruct"
-	"lukeshu.com/btrfs-tools/pkg/btrfs/btrfstyp"
+	"lukeshu.com/btrfs-tools/pkg/btrfs/internal"
 )
 
 type DevExtent struct { // DEV_EXTENT=204
 	ChunkTree     int64          `bin:"off=0, siz=8"`
-	ChunkObjectID btrfstyp.ObjID `bin:"off=8, siz=8"`
+	ChunkObjectID internal.ObjID `bin:"off=8, siz=8"`
 	ChunkOffset   int64          `bin:"off=16, siz=8"`
 	Length        int64          `bin:"off=24, siz=8"`
-	ChunkTreeUUID btrfstyp.UUID  `bin:"off=32, siz=16"`
+	ChunkTreeUUID internal.UUID  `bin:"off=32, siz=16"`
 	binstruct.End `bin:"off=48"`
 }
diff --git a/pkg/btrfs/btrfsitem/item_inode.go b/pkg/btrfs/btrfsitem/item_inode.go
index 0c7600e..4d38380 100644
--- a/pkg/btrfs/btrfsitem/item_inode.go
+++ b/pkg/btrfs/btrfsitem/item_inode.go
@@ -2,7 +2,7 @@ package btrfsitem
 
 import (
 	"lukeshu.com/btrfs-tools/pkg/binstruct"
-	"lukeshu.com/btrfs-tools/pkg/btrfs/btrfstyp"
+	"lukeshu.com/btrfs-tools/pkg/btrfs/internal"
 )
 
 type Inode struct { // INODE_ITEM=1
@@ -19,9 +19,9 @@ type Inode struct { // INODE_ITEM=1
 	Flags         uint64        `bin:"off=0x40, siz=0x8"`
 	Sequence      int64         `bin:"off=0x48, siz=0x8"`
 	Reserved      [4]int64      `bin:"off=0x50, siz=0x20"`
-	ATime         btrfstyp.Time `bin:"off=0x70, siz=0xc"`
-	CTime         btrfstyp.Time `bin:"off=0x7c, siz=0xc"`
-	MTime         btrfstyp.Time `bin:"off=0x88, siz=0xc"`
-	OTime         btrfstyp.Time `bin:"off=0x94, siz=0xc"`
+	ATime         internal.Time `bin:"off=0x70, siz=0xc"`
+	CTime         internal.Time `bin:"off=0x7c, siz=0xc"`
+	MTime         internal.Time `bin:"off=0x88, siz=0xc"`
+	OTime         internal.Time `bin:"off=0x94, siz=0xc"`
 	binstruct.End `bin:"off=0xa0"`
 }
diff --git a/pkg/btrfs/btrfsitem/item_inoderef.go b/pkg/btrfs/btrfsitem/item_inoderef.go
index 5a271ae..05426b2 100644
--- a/pkg/btrfs/btrfsitem/item_inoderef.go
+++ b/pkg/btrfs/btrfsitem/item_inoderef.go
@@ -6,7 +6,28 @@ import (
 
 type InodeRef struct { // INODE_REF=12
 	Index         int64 `bin:"off=0x0, siz=0x8"`
-	NameLen       int16 `bin:"off=0x8, siz=0x2"`
+	NameLen       uint16 `bin:"off=0x8, siz=0x2"`
 	binstruct.End `bin:"off=0xa"`
 	Name          []byte `bin:"-"`
 }
+
+func (o *InodeRef) UnmarshalBinary(dat []byte) (int, error) {
+	n, err := binstruct.UnmarshalWithoutInterface(dat, o)
+	if err != nil {
+		return n, err
+	}
+	dat = dat[n:]
+	o.Name = dat[:o.NameLen]
+	n += int(o.NameLen)
+	return n, nil
+}
+
+func (o InodeRef) MarshalBinary() ([]byte, error) {
+	o.NameLen = uint16(len(o.Name))
+	dat, err := binstruct.MarshalWithoutInterface(o)
+	if err != nil {
+		return dat, err
+	}
+	dat = append(dat, o.Name...)
+	return dat, nil
+}
diff --git a/pkg/btrfs/btrfsitem/item_root.go b/pkg/btrfs/btrfsitem/item_root.go
index c87a49b..a7867e8 100644
--- a/pkg/btrfs/btrfsitem/item_root.go
+++ b/pkg/btrfs/btrfsitem/item_root.go
@@ -2,7 +2,7 @@ package btrfsitem
 
 import (
 	"lukeshu.com/btrfs-tools/pkg/binstruct"
-	"lukeshu.com/btrfs-tools/pkg/btrfs/btrfstyp"
+	"lukeshu.com/btrfs-tools/pkg/btrfs/internal"
 	"lukeshu.com/btrfs-tools/pkg/util"
 )
 
@@ -10,28 +10,28 @@ type Root struct { // ROOT_ITEM=132
 	Inode         Inode                `bin:"off=0x0, siz=0xa0"`
 	Generation    int64                `bin:"off=0xa0, siz=0x8"`
 	RootDirID     int64                `bin:"off=0xa8, siz=0x8"`
-	ByteNr        btrfstyp.LogicalAddr `bin:"off=0xb0, siz=0x8"`
+	ByteNr        internal.LogicalAddr `bin:"off=0xb0, siz=0x8"`
 	ByteLimit     int64                `bin:"off=0xb8, siz=0x8"`
 	BytesUsed     int64                `bin:"off=0xc0, siz=0x8"`
 	LastSnapshot  int64                `bin:"off=0xc8, siz=0x8"`
 	Flags         RootFlags            `bin:"off=0xd0, siz=0x8"`
 	Refs          int32                `bin:"off=0xd8, siz=0x4"`
-	DropProgress  btrfstyp.Key         `bin:"off=0xdc, siz=0x11"`
+	DropProgress  internal.Key         `bin:"off=0xdc, siz=0x11"`
 	DropLevel     uint8                `bin:"off=0xed, siz=0x1"`
 	Level         uint8                `bin:"off=0xee, siz=0x1"`
 	GenerationV2  int64                `bin:"off=0xef, siz=0x8"`
-	UUID          btrfstyp.UUID        `bin:"off=0xF7, siz=0x10"`
-	ParentUUID    btrfstyp.UUID        `bin:"off=0x107, siz=0x10"`
-	ReceivedUUID  btrfstyp.UUID        `bin:"off=0x117, siz=0x10"`
+	UUID          internal.UUID        `bin:"off=0xF7, siz=0x10"`
+	ParentUUID    internal.UUID        `bin:"off=0x107, siz=0x10"`
+	ReceivedUUID  internal.UUID        `bin:"off=0x117, siz=0x10"`
 	CTransID      int64                `bin:"off=0x127, siz=0x8"`
 	OTransID      int64                `bin:"off=0x12f, siz=0x8"`
 	STransID      int64                `bin:"off=0x137, siz=0x8"`
 	RTransID      int64                `bin:"off=0x13f, siz=0x8"`
-	CTime         btrfstyp.Time        `bin:"off=0x147, siz=0xc"`
-	OTime         btrfstyp.Time        `bin:"off=0x153, siz=0xc"`
-	STime         btrfstyp.Time        `bin:"off=0x15F, siz=0xc"`
-	RTime         btrfstyp.Time        `bin:"off=0x16b, siz=0xc"`
-	GlobalTreeID  btrfstyp.ObjID       `bin:"off=0x177, siz=0x8"`
+	CTime         internal.Time        `bin:"off=0x147, siz=0xc"`
+	OTime         internal.Time        `bin:"off=0x153, siz=0xc"`
+	STime         internal.Time        `bin:"off=0x15F, siz=0xc"`
+	RTime         internal.Time        `bin:"off=0x16b, siz=0xc"`
+	GlobalTreeID  internal.ObjID       `bin:"off=0x177, siz=0x8"`
 	Reserved      [7]int64             `bin:"off=0x17f, siz=0x38"`
 	binstruct.End `bin:"off=0x1b7"`
 }
diff --git a/pkg/btrfs/btrfsitem/item_uuid.go b/pkg/btrfs/btrfsitem/item_uuid.go
index 315dd70..894ccff 100644
--- a/pkg/btrfs/btrfsitem/item_uuid.go
+++ b/pkg/btrfs/btrfsitem/item_uuid.go
@@ -2,20 +2,20 @@ package btrfsitem
 
 import (
 	"lukeshu.com/btrfs-tools/pkg/binstruct"
-	"lukeshu.com/btrfs-tools/pkg/btrfs/btrfstyp"
+	"lukeshu.com/btrfs-tools/pkg/btrfs/internal"
 )
 
 // The Key for this item is a UUID, and the item is a list of
 // subvolume IDs (ObjectIDs) that that UUID maps to.
 type UUIDMap struct { // UUID_SUBVOL=251 UUID_RECEIVED_SUBVOL=252
-	SubvolIDs []btrfstyp.ObjID
+	SubvolIDs []internal.ObjID
 }
 
 func (o *UUIDMap) UnmarshalBinary(dat []byte) (int, error) {
 	o.SubvolIDs = nil
 	var n int
 	for len(dat) > n {
-		var subvolID btrfstyp.ObjID
+		var subvolID internal.ObjID
 		_n, err := binstruct.Unmarshal(dat[n:], &subvolID)
 		n += _n
 		if err != nil {
diff --git a/pkg/btrfs/btrfsitem/items.go.bak b/pkg/btrfs/btrfsitem/items.go.bak
deleted file mode 100644
index 9a91d97..0000000
--- a/pkg/btrfs/btrfsitem/items.go.bak
+++ /dev/null
@@ -1,193 +0,0 @@
-package btrfsitem
-
-import (
-	"lukeshu.com/btrfs-tools/pkg/btrfs/btrfstyp"
-)
-
-type Type = btrfstyp.ItemType
-
-const (
-	BTRFS_UNTYPED_KEY = btrfstyp.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   = btrfstyp.ItemType(1)
-	BTRFS_INODE_REF_KEY    = btrfstyp.ItemType(12)
-	BTRFS_INODE_EXTREF_KEY = btrfstyp.ItemType(13)
-	BTRFS_XATTR_ITEM_KEY   = btrfstyp.ItemType(24)
-
-	BTRFS_VERITY_DESC_ITEM_KEY   = btrfstyp.ItemType(36) // new
-	BTRFS_VERITY_MERKLE_ITEM_KEY = btrfstyp.ItemType(37) // new
-
-	BTRFS_ORPHAN_ITEM_KEY = btrfstyp.ItemType(48)
-
-	BTRFS_DIR_LOG_ITEM_KEY  = btrfstyp.ItemType(60)
-	BTRFS_DIR_LOG_INDEX_KEY = btrfstyp.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  = btrfstyp.ItemType(84)
-	BTRFS_DIR_INDEX_KEY = btrfstyp.ItemType(96)
-
-	// extent data is for file data
-	BTRFS_EXTENT_DATA_KEY = btrfstyp.ItemType(108)
-
-	// csum items have the checksums for data in the extents
-	BTRFS_CSUM_ITEM_KEY = btrfstyp.ItemType(120) // new
-	// extent csums are stored in a separate tree and hold csums for
-	// an entire extent on disk.
-	BTRFS_EXTENT_CSUM_KEY = btrfstyp.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 = btrfstyp.ItemType(132)
-
-	// root backrefs tie subvols and snapshots to the directory entries that
-	// reference them
-	BTRFS_ROOT_BACKREF_KEY = btrfstyp.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 = btrfstyp.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 = btrfstyp.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 = btrfstyp.ItemType(169) // new
-
-	BTRFS_TREE_BLOCK_REF_KEY = btrfstyp.ItemType(176)
-
-	BTRFS_EXTENT_DATA_REF_KEY = btrfstyp.ItemType(178)
-
-	// old style extent backrefs
-	BTRFS_EXTENT_REF_V0_KEY = btrfstyp.ItemType(180)
-
-	BTRFS_SHARED_BLOCK_REF_KEY = btrfstyp.ItemType(182)
-
-	BTRFS_SHARED_DATA_REF_KEY = btrfstyp.ItemType(184)
-
-	// block groups give us hints into the extent allocation trees.  Which
-	// blocks are free etc etc
-	BTRFS_BLOCK_GROUP_ITEM_KEY = btrfstyp.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 = btrfstyp.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 = btrfstyp.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 = btrfstyp.ItemType(200) // new
-
-	BTRFS_DEV_EXTENT_KEY = btrfstyp.ItemType(204)
-	BTRFS_DEV_ITEM_KEY   = btrfstyp.ItemType(216)
-	BTRFS_CHUNK_ITEM_KEY = btrfstyp.ItemType(228)
-
-	// quota groups
-	BTRFS_QGROUP_STATUS_KEY   = btrfstyp.ItemType(240) // new
-	BTRFS_QGROUP_INFO_KEY     = btrfstyp.ItemType(242) // new
-	BTRFS_QGROUP_LIMIT_KEY    = btrfstyp.ItemType(244) // new
-	BTRFS_QGROUP_RELATION_KEY = btrfstyp.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 = btrfstyp.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 = btrfstyp.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 = btrfstyp.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          = btrfstyp.ItemType(251) // for UUIDs assigned to subvols // new
-	BTRFS_UUID_KEY_RECEIVED_SUBVOL = btrfstyp.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 = btrfstyp.ItemType(253)
-)
-
-/*
-func (t btrfstyp.ItemType) String() string {
-	names := map[btrfstyp.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)
-}
-*/
diff --git a/pkg/btrfs/fsck.go b/pkg/btrfs/fsck.go
index 3220a12..33ccd44 100644
--- a/pkg/btrfs/fsck.go
+++ b/pkg/btrfs/fsck.go
@@ -4,7 +4,6 @@ import (
 	"fmt"
 
 	"lukeshu.com/btrfs-tools/pkg/binstruct"
-	. "lukeshu.com/btrfs-tools/pkg/btrfs/btrfstyp"
 )
 
 // ScanForNodes mimics btrfs-progs
diff --git a/pkg/btrfs/internal.go b/pkg/btrfs/internal.go
new file mode 100644
index 0000000..5c0fc8b
--- /dev/null
+++ b/pkg/btrfs/internal.go
@@ -0,0 +1,20 @@
+package btrfs
+
+import (
+	"lukeshu.com/btrfs-tools/pkg/btrfs/internal"
+)
+
+type (
+	// (u)int64 types
+
+	Generation   = internal.Generation
+	ObjID        = internal.ObjID
+	LogicalAddr  = internal.LogicalAddr
+	PhysicalAddr = internal.PhysicalAddr
+
+	// complex types
+
+	Key  = internal.Key
+	Time = internal.Time
+	UUID = internal.UUID
+)
diff --git a/pkg/btrfs/btrfstyp/misc.go b/pkg/btrfs/internal/misc.go
index b0847f8..e7d9dd6 100644
--- a/pkg/btrfs/btrfstyp/misc.go
+++ b/pkg/btrfs/internal/misc.go
@@ -1,10 +1,9 @@
-package btrfstyp
+package internal
 
 import (
 	"time"
 
 	"lukeshu.com/btrfs-tools/pkg/binstruct"
-	"lukeshu.com/btrfs-tools/pkg/btrfs/internal"
 )
 
 type (
@@ -14,9 +13,9 @@ type (
 )
 
 type Key struct {
-	ObjectID      ObjID             `bin:"off=0, siz=8"` // Each tree has its own set of Object IDs.
-	ItemType      internal.ItemType `bin:"off=8, siz=1"`
-	Offset        uint64            `bin:"off=9, siz=8"` // The meaning depends on the item type.
+	ObjectID      ObjID    `bin:"off=0, siz=8"` // Each tree has its own set of Object IDs.
+	ItemType      ItemType `bin:"off=8, siz=1"`
+	Offset        uint64   `bin:"off=9, siz=8"` // The meaning depends on the item type.
 	binstruct.End `bin:"off=11"`
 }
 
diff --git a/pkg/btrfs/btrfstyp/objid.go b/pkg/btrfs/internal/objid.go
index dce8c18..c3b25f3 100644
--- a/pkg/btrfs/btrfstyp/objid.go
+++ b/pkg/btrfs/internal/objid.go
@@ -1,9 +1,8 @@
-package btrfstyp
+package internal
 
 import (
 	"fmt"
 
-	"lukeshu.com/btrfs-tools/pkg/btrfs/internal"
 	"lukeshu.com/btrfs-tools/pkg/util"
 )
 
@@ -52,9 +51,9 @@ const (
 	BTRFS_EMPTY_SUBVOL_DIR_OBJECTID = ObjID(2)
 )
 
-func (id ObjID) Format(typ internal.ItemType) string {
+func (id ObjID) Format(typ ItemType) string {
 	switch typ {
-	case internal.PERSISTENT_ITEM_KEY:
+	case PERSISTENT_ITEM_KEY:
 		names := map[ObjID]string{
 			BTRFS_DEV_STATS_OBJECTID: "DEV_STATS",
 		}
@@ -62,15 +61,15 @@ func (id ObjID) Format(typ internal.ItemType) string {
 			return name
 		}
 		return fmt.Sprintf("%d", int64(id))
-	case internal.DEV_EXTENT_KEY:
+	case DEV_EXTENT_KEY:
 		return fmt.Sprintf("%d", int64(id))
-	case internal.QGROUP_RELATION_KEY:
+	case QGROUP_RELATION_KEY:
 		return fmt.Sprintf("%d/%d",
 			uint64(id)>>48,
 			uint64(id)&((1<<48)-1))
-	case internal.UUID_SUBVOL_KEY, internal.UUID_RECEIVED_SUBVOL_KEY:
+	case UUID_SUBVOL_KEY, UUID_RECEIVED_SUBVOL_KEY:
 		return fmt.Sprintf("0x%016x", uint64(id))
-	case internal.DEV_ITEM_KEY:
+	case DEV_ITEM_KEY:
 		names := map[ObjID]string{
 			BTRFS_BALANCE_OBJECTID:         "BALANCE",
 			BTRFS_ORPHAN_OBJECTID:          "ORPHAN",
@@ -89,7 +88,7 @@ func (id ObjID) Format(typ internal.ItemType) string {
 			return name
 		}
 		return fmt.Sprintf("%d", int64(id))
-	case internal.CHUNK_ITEM_KEY:
+	case CHUNK_ITEM_KEY:
 		names := map[ObjID]string{
 			BTRFS_BALANCE_OBJECTID:         "BALANCE",
 			BTRFS_ORPHAN_OBJECTID:          "ORPHAN",
@@ -141,5 +140,5 @@ func (id ObjID) Format(typ internal.ItemType) string {
 }
 
 func (id ObjID) String() string {
-	return id.Format(internal.UNTYPED_KEY)
+	return id.Format(UNTYPED_KEY)
 }
diff --git a/pkg/btrfs/btrfstyp/uuid.go b/pkg/btrfs/internal/uuid.go
index 8b0c92e..ff274d9 100644
--- a/pkg/btrfs/btrfstyp/uuid.go
+++ b/pkg/btrfs/internal/uuid.go
@@ -1,4 +1,4 @@
-package btrfstyp
+package internal
 
 import (
 	"bytes"
diff --git a/pkg/btrfs/io1_device.go b/pkg/btrfs/io1_device.go
index ed418a0..efd8cb9 100644
--- a/pkg/btrfs/io1_device.go
+++ b/pkg/btrfs/io1_device.go
@@ -4,7 +4,6 @@ import (
 	"fmt"
 	"os"
 
-	. "lukeshu.com/btrfs-tools/pkg/btrfs/btrfstyp"
 	"lukeshu.com/btrfs-tools/pkg/util"
 )
 
diff --git a/pkg/btrfs/io2_fs.go b/pkg/btrfs/io2_fs.go
index 9b1e717..a74d4a3 100644
--- a/pkg/btrfs/io2_fs.go
+++ b/pkg/btrfs/io2_fs.go
@@ -7,7 +7,6 @@ import (
 
 	"lukeshu.com/btrfs-tools/pkg/binstruct"
 	"lukeshu.com/btrfs-tools/pkg/btrfs/btrfsitem"
-	. "lukeshu.com/btrfs-tools/pkg/btrfs/btrfstyp"
 	"lukeshu.com/btrfs-tools/pkg/util"
 )
 
diff --git a/pkg/btrfs/types_btree.go b/pkg/btrfs/types_btree.go
index 2807cee..1eb104d 100644
--- a/pkg/btrfs/types_btree.go
+++ b/pkg/btrfs/types_btree.go
@@ -5,7 +5,6 @@ import (
 	"fmt"
 
 	"lukeshu.com/btrfs-tools/pkg/binstruct"
-	. "lukeshu.com/btrfs-tools/pkg/btrfs/btrfstyp"
 	"lukeshu.com/btrfs-tools/pkg/util"
 )
 
diff --git a/pkg/btrfs/types_superblock.go b/pkg/btrfs/types_superblock.go
index 1b69c03..47dd3b0 100644
--- a/pkg/btrfs/types_superblock.go
+++ b/pkg/btrfs/types_superblock.go
@@ -6,7 +6,6 @@ import (
 
 	"lukeshu.com/btrfs-tools/pkg/binstruct"
 	"lukeshu.com/btrfs-tools/pkg/btrfs/btrfsitem"
-	. "lukeshu.com/btrfs-tools/pkg/btrfs/btrfstyp"
 	"lukeshu.com/btrfs-tools/pkg/util"
 )