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-rw-r--r--pkg/btrfs/io2_lv.go2
-rw-r--r--pkg/btrfs/io3_btree.go115
-rw-r--r--pkg/btrfs/io4_fs.go27
-rw-r--r--pkg/btrfs/types_node.go3
4 files changed, 101 insertions, 46 deletions
diff --git a/pkg/btrfs/io2_lv.go b/pkg/btrfs/io2_lv.go
index 0564066..486a4ae 100644
--- a/pkg/btrfs/io2_lv.go
+++ b/pkg/btrfs/io2_lv.go
@@ -153,7 +153,7 @@ func (fs *FS) initDev(sb *util.Ref[btrfsvol.PhysicalAddr, Superblock]) error {
}
}
}
- if err := fs.TreeWalk(sb.Data.ChunkTree, TreeWalkHandler{
+ if err := fs.TreeWalk(CHUNK_TREE_OBJECTID, TreeWalkHandler{
Item: func(_ TreePath, item Item) error {
if item.Head.Key.ItemType != btrfsitem.CHUNK_ITEM_KEY {
return nil
diff --git a/pkg/btrfs/io3_btree.go b/pkg/btrfs/io3_btree.go
index 1bcb193..be46d21 100644
--- a/pkg/btrfs/io3_btree.go
+++ b/pkg/btrfs/io3_btree.go
@@ -5,11 +5,11 @@ import (
"fmt"
"io"
iofs "io/fs"
- "math"
"strings"
"github.com/datawire/dlib/derror"
+ "lukeshu.com/btrfs-tools/pkg/btrfs/btrfsitem"
"lukeshu.com/btrfs-tools/pkg/btrfs/btrfsvol"
"lukeshu.com/btrfs-tools/pkg/util"
)
@@ -74,16 +74,12 @@ type TreePathElem struct {
// being pointed at.
NodeAddr btrfsvol.LogicalAddr
// NodeLevel is the expected or actual level of the node at
- // NodeAddr, or 255 if there is no knowledge of the level.
+ // NodeAddr.
NodeLevel uint8
}
func (elem TreePathElem) writeNodeTo(w io.Writer) {
- if elem.NodeLevel != math.MaxUint8 {
- fmt.Fprintf(w, "node:%d@%v", elem.NodeLevel, elem.NodeAddr)
- } else {
- fmt.Fprintf(w, "node@%v", elem.NodeAddr)
- }
+ fmt.Fprintf(w, "node:%d@%v", elem.NodeLevel, elem.NodeAddr)
}
func (path TreePath) String() string {
@@ -102,6 +98,75 @@ func (path TreePath) String() string {
return ret.String()
}
+// A treeRoot is more-or-less a btrfsitem.Root, but simpler and generalized for
+type treeRoot struct {
+ TreeID ObjID
+ RootNode btrfsvol.LogicalAddr
+ Level uint8
+ Generation Generation
+}
+
+func (fs *FS) lookupTree(treeID ObjID) (*treeRoot, error) {
+ sb, err := fs.Superblock()
+ if err != nil {
+ return nil, err
+ }
+ switch treeID {
+ case ROOT_TREE_OBJECTID:
+ return &treeRoot{
+ TreeID: treeID,
+ RootNode: sb.Data.RootTree,
+ Level: sb.Data.RootLevel,
+ Generation: sb.Data.Generation, // XXX: same generation as LOG_TREE?
+ }, nil
+ case CHUNK_TREE_OBJECTID:
+ return &treeRoot{
+ TreeID: treeID,
+ RootNode: sb.Data.ChunkTree,
+ Level: sb.Data.ChunkLevel,
+ Generation: sb.Data.ChunkRootGeneration,
+ }, nil
+ case TREE_LOG_OBJECTID:
+ return &treeRoot{
+ TreeID: treeID,
+ RootNode: sb.Data.LogTree,
+ Level: sb.Data.LogLevel,
+ Generation: sb.Data.Generation, // XXX: same generation as ROOT_TREE?
+ }, nil
+ case BLOCK_GROUP_TREE_OBJECTID:
+ return &treeRoot{
+ TreeID: treeID,
+ RootNode: sb.Data.BlockGroupRoot,
+ Level: sb.Data.BlockGroupRootLevel,
+ Generation: sb.Data.BlockGroupRootGeneration,
+ }, nil
+ default:
+ rootItem, err := fs.TreeSearch(ROOT_TREE_OBJECTID, func(key Key) int {
+ if key.ObjectID == treeID && key.ItemType == btrfsitem.ROOT_ITEM_KEY {
+ return 0
+ }
+ return Key{
+ ObjectID: treeID,
+ ItemType: btrfsitem.ROOT_ITEM_KEY,
+ Offset: 0,
+ }.Cmp(key)
+ })
+ if err != nil {
+ return nil, err
+ }
+ rootItemBody, ok := rootItem.Body.(btrfsitem.Root)
+ if !ok {
+ return nil, fmt.Errorf("malformed ROOT_ITEM for tree %v", treeID)
+ }
+ return &treeRoot{
+ TreeID: treeID,
+ RootNode: rootItemBody.ByteNr,
+ Level: rootItemBody.Level,
+ Generation: rootItemBody.Generation,
+ }, nil
+ }
+}
+
type TreeWalkHandler struct {
// Callbacks for entire nodes
PreNode func(TreePath) error
@@ -127,12 +192,16 @@ type TreeWalkHandler struct {
// else:
// 004 .Item()
// 007 .PostNode()
-func (fs *FS) TreeWalk(treeRoot btrfsvol.LogicalAddr, cbs TreeWalkHandler) error {
+func (fs *FS) TreeWalk(treeID ObjID, cbs TreeWalkHandler) error {
+ rootInfo, err := fs.lookupTree(treeID)
+ if err != nil {
+ return err
+ }
path := TreePath{
TreePathElem{
ItemIdx: -1,
- NodeAddr: treeRoot,
- NodeLevel: math.MaxUint8,
+ NodeAddr: rootInfo.RootNode,
+ NodeLevel: rootInfo.Level,
},
}
return fs.treeWalk(path, cbs)
@@ -216,12 +285,12 @@ func (fs *FS) treeWalk(path TreePath, cbs TreeWalkHandler) error {
return nil
}
-func (fs *FS) treeSearch(treeRoot btrfsvol.LogicalAddr, fn func(Key) int) (TreePath, *util.Ref[btrfsvol.LogicalAddr, Node], error) {
+func (fs *FS) treeSearch(treeRoot treeRoot, fn func(Key) int) (TreePath, *util.Ref[btrfsvol.LogicalAddr, Node], error) {
path := TreePath{
TreePathElem{
ItemIdx: -1,
- NodeAddr: treeRoot,
- NodeLevel: math.MaxUint8,
+ NodeAddr: treeRoot.RootNode,
+ NodeLevel: treeRoot.Level,
},
}
for {
@@ -418,16 +487,20 @@ func (fs *FS) next(path TreePath, node *util.Ref[btrfsvol.LogicalAddr, Node]) (T
return path, node, nil
}
-func (fs *FS) TreeSearch(treeRoot btrfsvol.LogicalAddr, fn func(Key) int) (Item, error) {
- path, node, err := fs.treeSearch(treeRoot, fn)
+func (fs *FS) TreeSearch(treeID ObjID, fn func(Key) int) (Item, error) {
+ rootInfo, err := fs.lookupTree(treeID)
+ if err != nil {
+ return Item{}, err
+ }
+ path, node, err := fs.treeSearch(*rootInfo, fn)
if err != nil {
return Item{}, err
}
return node.Data.BodyLeaf[path[len(path)-1].ItemIdx], nil
}
-func (fs *FS) TreeLookup(treeRoot btrfsvol.LogicalAddr, key Key) (Item, error) {
- item, err := fs.TreeSearch(treeRoot, key.Cmp)
+func (fs *FS) TreeLookup(treeID ObjID, key Key) (Item, error) {
+ item, err := fs.TreeSearch(treeID, key.Cmp)
if err != nil {
err = fmt.Errorf("item with key=%v: %w", key, err)
}
@@ -438,8 +511,12 @@ func (fs *FS) TreeLookup(treeRoot btrfsvol.LogicalAddr, key Key) (Item, error) {
// return *both* a list of items and an error.
//
// If no such item is found, an error that is io/fs.ErrNotExist is returned.
-func (fs *FS) TreeSearchAll(treeRoot btrfsvol.LogicalAddr, fn func(Key) int) ([]Item, error) {
- middlePath, middleNode, err := fs.treeSearch(treeRoot, fn)
+func (fs *FS) TreeSearchAll(treeID ObjID, fn func(Key) int) ([]Item, error) {
+ rootInfo, err := fs.lookupTree(treeID)
+ if err != nil {
+ return nil, err
+ }
+ middlePath, middleNode, err := fs.treeSearch(*rootInfo, fn)
if err != nil {
return nil, err
}
diff --git a/pkg/btrfs/io4_fs.go b/pkg/btrfs/io4_fs.go
index 37d949e..cd8e281 100644
--- a/pkg/btrfs/io4_fs.go
+++ b/pkg/btrfs/io4_fs.go
@@ -66,13 +66,7 @@ type Subvolume struct {
func (sv *Subvolume) init() {
sv.rootOnce.Do(func() {
- sb, err := sv.FS.Superblock()
- if err != nil {
- sv.rootErr = err
- return
- }
-
- root, err := sv.FS.TreeLookup(sb.Data.RootTree, Key{
+ root, err := sv.FS.TreeLookup(ROOT_TREE_OBJECTID, Key{
ObjectID: sv.TreeID,
ItemType: btrfsitem.ROOT_ITEM_KEY,
Offset: 0,
@@ -97,22 +91,12 @@ func (sv *Subvolume) GetRootInode() (ObjID, error) {
return sv.rootVal.RootDirID, sv.rootErr
}
-func (sv *Subvolume) GetFSTree() (btrfsvol.LogicalAddr, error) {
- sv.init()
- return sv.rootVal.ByteNr, sv.rootErr
-}
-
func (sv *Subvolume) LoadBareInode(inode ObjID) (*BareInode, error) {
val := sv.bareInodeCache.GetOrElse(inode, func() (val *BareInode) {
val = &BareInode{
Inode: inode,
}
- tree, err := sv.GetFSTree()
- if err != nil {
- val.Errs = append(val.Errs, err)
- return
- }
- item, err := sv.FS.TreeLookup(tree, Key{
+ item, err := sv.FS.TreeLookup(sv.TreeID, Key{
ObjectID: inode,
ItemType: btrfsitem.INODE_ITEM_KEY,
Offset: 0,
@@ -144,12 +128,7 @@ func (sv *Subvolume) LoadFullInode(inode ObjID) (*FullInode, error) {
Inode: inode,
},
}
- tree, err := sv.GetFSTree()
- if err != nil {
- val.Errs = append(val.Errs, err)
- return
- }
- items, err := sv.FS.TreeSearchAll(tree, func(key Key) int {
+ items, err := sv.FS.TreeSearchAll(sv.TreeID, func(key Key) int {
return util.CmpUint(inode, key.ObjectID)
})
if err != nil {
diff --git a/pkg/btrfs/types_node.go b/pkg/btrfs/types_node.go
index 92f7513..4382a91 100644
--- a/pkg/btrfs/types_node.go
+++ b/pkg/btrfs/types_node.go
@@ -4,7 +4,6 @@ import (
"encoding/binary"
"errors"
"fmt"
- "math"
"lukeshu.com/btrfs-tools/pkg/binstruct"
"lukeshu.com/btrfs-tools/pkg/btrfs/btrfsitem"
@@ -404,7 +403,7 @@ func (fs *FS) readNodeAtLevel(addr btrfsvol.LogicalAddr, expLevel uint8) (*util.
if err != nil {
return node, err
}
- if expLevel != math.MaxUint8 && node.Data.Head.Level != expLevel {
+ if node.Data.Head.Level != expLevel {
return node, fmt.Errorf("btrfs.FS.ReadNode: node@%v: expected level %v but has level %v",
node.Addr, expLevel, node.Data.Head.Level)
}
generated by cgit v1.2.3-2-g168b (git 2.25.1) at 2024-11-04 16:30:14 +0000