btrfsutil: Merge KeyIO in to RebuiltForrest

3 files changed, 30 insertions, 44 deletions

diff --git a/lib/btrfsutil/rebuilt_forrest.go b/lib/btrfsutil/rebuilt_forrest.go
index 0e8f5ad..25d953b 100644
--- a/lib/btrfsutil/rebuilt_forrest.go
+++ b/lib/btrfsutil/rebuilt_forrest.go
@@ -6,6 +6,7 @@ package btrfsutil
 
 import (
 	"context"
+	"sync"
 
 	"github.com/datawire/dlib/dlog"
 
@@ -14,6 +15,7 @@ import (
 	"git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfstree"
 	"git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfsvol"
 	"git.lukeshu.com/btrfs-progs-ng/lib/containers"
+	"git.lukeshu.com/btrfs-progs-ng/lib/diskio"
 	"git.lukeshu.com/btrfs-progs-ng/lib/slices"
 	"git.lukeshu.com/btrfs-progs-ng/lib/textui"
 )
@@ -57,26 +59,30 @@ type RebuiltForrestCallbacks interface {
 // NewRebuiltForrest().
 type RebuiltForrest struct {
 	// static
+	file  diskio.File[btrfsvol.LogicalAddr]
 	sb    btrfstree.Superblock
 	graph Graph
-	keyIO *KeyIO
 	cb    RebuiltForrestCallbacks
 
 	// mutable
+
 	treesMu  nestedMutex
 	trees    map[btrfsprim.ObjID]*RebuiltTree // must hold .treesMu to access
 	leafs    containers.ARCache[btrfsprim.ObjID, map[btrfsvol.LogicalAddr]containers.Set[btrfsvol.LogicalAddr]]
 	incItems containers.ARCache[btrfsprim.ObjID, *itemIndex]
 	excItems containers.ARCache[btrfsprim.ObjID, *itemIndex]
+
+	nodesMu sync.Mutex
+	nodes   containers.ARCache[btrfsvol.LogicalAddr, *btrfstree.Node]
 }
 
 // NewRebuiltForrest returns a new RebuiltForrest instance.  All of
 // the callbacks must be non-nil.
-func NewRebuiltForrest(sb btrfstree.Superblock, graph Graph, keyIO *KeyIO, cb RebuiltForrestCallbacks) *RebuiltForrest {
+func NewRebuiltForrest(file diskio.File[btrfsvol.LogicalAddr], sb btrfstree.Superblock, graph Graph, cb RebuiltForrestCallbacks) *RebuiltForrest {
 	return &RebuiltForrest{
+		file:  file,
 		sb:    sb,
 		graph: graph,
-		keyIO: keyIO,
 		cb:    cb,
 
 		trees: make(map[btrfsprim.ObjID]*RebuiltTree),
@@ -89,6 +95,13 @@ func NewRebuiltForrest(sb btrfstree.Superblock, graph Graph, keyIO *KeyIO, cb Re
 		excItems: containers.ARCache[btrfsprim.ObjID, *itemIndex]{
 			MaxLen: textui.Tunable(8),
 		},
+
+		nodes: containers.ARCache[btrfsvol.LogicalAddr, *btrfstree.Node]{
+			MaxLen: textui.Tunable(8),
+			OnRemove: func(_ btrfsvol.LogicalAddr, node *btrfstree.Node) {
+				node.Free()
+			},
+		},
 	}
 }
 
diff --git a/lib/btrfsutil/rebuilt_readitem.go b/lib/btrfsutil/rebuilt_readitem.go
index 7e9be09..68aabdd 100644
--- a/lib/btrfsutil/rebuilt_readitem.go
+++ b/lib/btrfsutil/rebuilt_readitem.go
@@ -7,7 +7,6 @@ package btrfsutil
 import (
 	"context"
 	"fmt"
-	"sync"
 
 	"github.com/datawire/dlib/dlog"
 
@@ -16,8 +15,6 @@ import (
 	"git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfstree"
 	"git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfsvol"
 	"git.lukeshu.com/btrfs-progs-ng/lib/containers"
-	"git.lukeshu.com/btrfs-progs-ng/lib/diskio"
-	"git.lukeshu.com/btrfs-progs-ng/lib/textui"
 )
 
 type ItemPtr struct {
@@ -29,43 +26,19 @@ func (ptr ItemPtr) String() string {
 	return fmt.Sprintf("node@%v[%v]", ptr.Node, ptr.Slot)
 }
 
-type KeyIO struct {
-	rawFile diskio.File[btrfsvol.LogicalAddr]
-	sb      btrfstree.Superblock
-	graph   Graph
-
-	mu    sync.Mutex
-	cache containers.ARCache[btrfsvol.LogicalAddr, *btrfstree.Node]
-}
-
-func NewKeyIO(file diskio.File[btrfsvol.LogicalAddr], sb btrfstree.Superblock, graph Graph) *KeyIO {
-	return &KeyIO{
-		rawFile: file,
-		sb:      sb,
-		graph:   graph,
-
-		cache: containers.ARCache[btrfsvol.LogicalAddr, *btrfstree.Node]{
-			MaxLen: textui.Tunable(8),
-			OnRemove: func(_ btrfsvol.LogicalAddr, node *btrfstree.Node) {
-				node.Free()
-			},
-		},
-	}
-}
-
-func (o *KeyIO) readNode(ctx context.Context, laddr btrfsvol.LogicalAddr) *btrfstree.Node {
-	if cached, ok := o.cache.Load(laddr); ok {
+func (ts *RebuiltForrest) readNode(ctx context.Context, laddr btrfsvol.LogicalAddr) *btrfstree.Node {
+	if cached, ok := ts.nodes.Load(laddr); ok {
 		dlog.Tracef(ctx, "cache-hit node@%v", laddr)
 		return cached
 	}
 
-	graphInfo, ok := o.graph.Nodes[laddr]
+	graphInfo, ok := ts.graph.Nodes[laddr]
 	if !ok {
 		panic(fmt.Errorf("should not happen: node@%v is not mentioned in the in-memory graph", laddr))
 	}
 
 	dlog.Debugf(ctx, "cache-miss node@%v, reading...", laddr)
-	node, err := btrfstree.ReadNode[btrfsvol.LogicalAddr](o.rawFile, o.sb, laddr, btrfstree.NodeExpectations{
+	node, err := btrfstree.ReadNode[btrfsvol.LogicalAddr](ts.file, ts.sb, laddr, btrfstree.NodeExpectations{
 		LAddr:      containers.Optional[btrfsvol.LogicalAddr]{OK: true, Val: laddr},
 		Level:      containers.Optional[uint8]{OK: true, Val: graphInfo.Level},
 		Generation: containers.Optional[btrfsprim.Generation]{OK: true, Val: graphInfo.Generation},
@@ -83,23 +56,23 @@ func (o *KeyIO) readNode(ctx context.Context, laddr btrfsvol.LogicalAddr) *btrfs
 		panic(fmt.Errorf("should not happen: i/o error: %w", err))
 	}
 
-	o.cache.Store(laddr, node)
+	ts.nodes.Store(laddr, node)
 
 	return node
 }
 
-func (o *KeyIO) ReadItem(ctx context.Context, ptr ItemPtr) btrfsitem.Item {
-	o.mu.Lock()
-	defer o.mu.Unlock()
-	if o.graph.Nodes[ptr.Node].Level != 0 {
-		panic(fmt.Errorf("should not happen: btrfsutil.KeyIO.ReadItem called for non-leaf node@%v", ptr.Node))
+func (ts *RebuiltForrest) readItem(ctx context.Context, ptr ItemPtr) btrfsitem.Item {
+	ts.nodesMu.Lock()
+	defer ts.nodesMu.Unlock()
+	if ts.graph.Nodes[ptr.Node].Level != 0 {
+		panic(fmt.Errorf("should not happen: btrfsutil.RebuiltForrest.readItem called for non-leaf node@%v", ptr.Node))
 	}
 	if ptr.Slot < 0 {
-		panic(fmt.Errorf("should not happen: btrfsutil.KeyIO.ReadItem called for negative item slot: %v", ptr.Slot))
+		panic(fmt.Errorf("should not happen: btrfsutil.RebuiltForrest.readItem called for negative item slot: %v", ptr.Slot))
 	}
-	items := o.readNode(ctx, ptr.Node).BodyLeaf
+	items := ts.readNode(ctx, ptr.Node).BodyLeaf
 	if ptr.Slot >= len(items) {
-		panic(fmt.Errorf("should not happen: btrfsutil.KeyIO.ReadItem called for out-of-bounds item slot: slot=%v len=%v",
+		panic(fmt.Errorf("should not happen: btrfsutil.RebuiltForrest.readItem called for out-of-bounds item slot: slot=%v len=%v",
 			ptr.Slot, len(items)))
 	}
 	return items[ptr.Slot].Body.CloneItem()
diff --git a/lib/btrfsutil/rebuilt_tree.go b/lib/btrfsutil/rebuilt_tree.go
index 3133a9e..820913e 100644
--- a/lib/btrfsutil/rebuilt_tree.go
+++ b/lib/btrfsutil/rebuilt_tree.go
@@ -329,7 +329,7 @@ func (tree *RebuiltTree) ReadItem(ctx context.Context, key btrfsprim.Key) btrfsi
 	if !ok {
 		panic(fmt.Errorf("should not happen: btrfsutil.RebuiltTree.ReadItem called for not-included key: %v", key))
 	}
-	return tree.forrest.keyIO.ReadItem(ctx, ptr)
+	return tree.forrest.readItem(ctx, ptr)
 }
 
 // LeafToRoots returns the list of potential roots (to pass to