more better

packet/virtio.go

@@ -5,18 +5,35 @@ import (
 )
 
 type VirtIOPacket struct {
-	Payload []byte
-	buf     []byte
-	Header  virtio.NetHdr
+	Payload   []byte
+	Header    virtio.NetHdr
+	Chains    []uint16
+	ChainRefs [][]byte
+	// RecycleDescriptorChains(chains []uint16, kick bool) error
+	Recycler func([]uint16, bool) error
 }
 
 func NewVIO() *VirtIOPacket {
 	out := new(VirtIOPacket)
 	out.Payload = make([]byte, Size)
-	out.buf = out.Payload
+	out.ChainRefs = make([][]byte, 0, 4)
+	out.Chains = make([]uint16, 0, 8)
 	return out
 }
 
 func (v *VirtIOPacket) Reset() {
-	v.Payload = v.buf[:Size]
+	v.Payload = nil
+	v.ChainRefs = v.ChainRefs[:0]
+	v.Chains = v.Chains[:0]
+}
+
+func (v *VirtIOPacket) Recycle(lastOne bool) error {
+	if v.Recycler != nil {
+		err := v.Recycler(v.Chains, lastOne)
+		if err != nil {
+			return err
+		}
+	}
+	v.Reset()
+	return nil
 }