2 files changed, 22 insertions, 17 deletions

diff --git a/pkg/tcpip/link/sharedmem/sharedmem.go b/pkg/tcpip/link/sharedmem/sharedmem.go
index 507c76b76..7fb8a6c49 100644
--- a/pkg/tcpip/link/sharedmem/sharedmem.go
+++ b/pkg/tcpip/link/sharedmem/sharedmem.go
@@ -186,8 +186,7 @@ func (e *endpoint) LinkAddress() tcpip.LinkAddress {
 // AddHeader implements stack.LinkEndpoint.AddHeader.
 func (e *endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) {
 	// Add ethernet header if needed.
-	eth := header.Ethernet(pkt.Header.Prepend(header.EthernetMinimumSize))
-	pkt.LinkHeader = buffer.View(eth)
+	eth := header.Ethernet(pkt.LinkHeader().Push(header.EthernetMinimumSize))
 	ethHdr := &header.EthernetFields{
 		DstAddr: remote,
 		Type:    protocol,
@@ -207,10 +206,10 @@ func (e *endpoint) AddHeader(local, remote tcpip.LinkAddress, protocol tcpip.Net
 func (e *endpoint) WritePacket(r *stack.Route, _ *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) *tcpip.Error {
 	e.AddHeader(r.LocalLinkAddress, r.RemoteLinkAddress, protocol, pkt)
 
-	v := pkt.Data.ToView()
+	views := pkt.Views()
 	// Transmit the packet.
 	e.mu.Lock()
-	ok := e.tx.transmit(pkt.Header.View(), v)
+	ok := e.tx.transmit(views...)
 	e.mu.Unlock()
 
 	if !ok {
@@ -227,10 +226,10 @@ func (e *endpoint) WritePackets(r *stack.Route, _ *stack.GSO, pkts stack.PacketB
 
 // WriteRawPacket implements stack.LinkEndpoint.WriteRawPacket.
 func (e *endpoint) WriteRawPacket(vv buffer.VectorisedView) *tcpip.Error {
-	v := vv.ToView()
+	views := vv.Views()
 	// Transmit the packet.
 	e.mu.Lock()
-	ok := e.tx.transmit(v, buffer.View{})
+	ok := e.tx.transmit(views...)
 	e.mu.Unlock()
 
 	if !ok {
@@ -276,16 +275,18 @@ func (e *endpoint) dispatchLoop(d stack.NetworkDispatcher) {
 			rxb[i].Size = e.bufferSize
 		}
 
-		if n < header.EthernetMinimumSize {
+		pkt := stack.NewPacketBuffer(stack.PacketBufferOptions{
+			Data: buffer.View(b).ToVectorisedView(),
+		})
+
+		hdr, ok := pkt.LinkHeader().Consume(header.EthernetMinimumSize)
+		if !ok {
 			continue
 		}
+		eth := header.Ethernet(hdr)
 
 		// Send packet up the stack.
-		eth := header.Ethernet(b[:header.EthernetMinimumSize])
-		d.DeliverNetworkPacket(eth.SourceAddress(), eth.DestinationAddress(), eth.Type(), &stack.PacketBuffer{
-			Data:       buffer.View(b[header.EthernetMinimumSize:]).ToVectorisedView(),
-			LinkHeader: buffer.View(eth),
-		})
+		d.DeliverNetworkPacket(eth.SourceAddress(), eth.DestinationAddress(), eth.Type(), pkt)
 	}
 
 	// Clean state.
diff --git a/pkg/tcpip/link/sharedmem/tx.go b/pkg/tcpip/link/sharedmem/tx.go
index 6b8d7859d..44f421c2d 100644
--- a/pkg/tcpip/link/sharedmem/tx.go
+++ b/pkg/tcpip/link/sharedmem/tx.go
@@ -18,6 +18,7 @@ import (
 	"math"
 	"syscall"
 
+	"gvisor.dev/gvisor/pkg/tcpip/buffer"
 	"gvisor.dev/gvisor/pkg/tcpip/link/sharedmem/queue"
 )
 
@@ -76,9 +77,9 @@ func (t *tx) cleanup() {
 	syscall.Munmap(t.data)
 }
 
-// transmit sends a packet made up of up to two buffers. Returns a boolean that
-// specifies whether the packet was successfully transmitted.
-func (t *tx) transmit(a, b []byte) bool {
+// transmit sends a packet made of bufs. Returns a boolean that specifies
+// whether the packet was successfully transmitted.
+func (t *tx) transmit(bufs ...buffer.View) bool {
 	// Pull completions from the tx queue and add their buffers back to the
 	// pool so that we can reuse them.
 	for {
@@ -93,7 +94,10 @@ func (t *tx) transmit(a, b []byte) bool {
 	}
 
 	bSize := t.bufs.entrySize
-	total := uint32(len(a) + len(b))
+	total := uint32(0)
+	for _, data := range bufs {
+		total += uint32(len(data))
+	}
 	bufCount := (total + bSize - 1) / bSize
 
 	// Allocate enough buffers to hold all the data.
@@ -115,7 +119,7 @@ func (t *tx) transmit(a, b []byte) bool {
 	// Copy data into allocated buffers.
 	nBuf := buf
 	var dBuf []byte
-	for _, data := range [][]byte{a, b} {
+	for _, data := range bufs {
 		for len(data) > 0 {
 			if len(dBuf) == 0 {
 				dBuf = t.data[nBuf.Offset:][:nBuf.Size]