Update {LinkEndpoint,NetworkEndpoint}#WritePacket to take a VectorisedView

Makes it possible to avoid copying or allocating in cases where DeliverNetworkPacket (rx)
needs to turn around and call WritePacket (tx) with its VectorisedView.

Also removes the restriction on having VectorisedViews with multiple views in the write path.

PiperOrigin-RevId: 211728717
Change-Id: Ie03a65ecb4e28bd15ebdb9c69f05eced18fdfcff

1 files changed, 3 insertions, 3 deletions

diff --git a/pkg/tcpip/network/arp/arp.go b/pkg/tcpip/network/arp/arp.go
index e7dfc6444..6bf4be868 100644
--- a/pkg/tcpip/network/arp/arp.go
+++ b/pkg/tcpip/network/arp/arp.go
@@ -74,7 +74,7 @@ func (e *endpoint) MaxHeaderLength() uint16 {
 
 func (e *endpoint) Close() {}
 
-func (e *endpoint) WritePacket(r *stack.Route, hdr *buffer.Prependable, payload buffer.View, protocol tcpip.TransportProtocolNumber) *tcpip.Error {
+func (e *endpoint) WritePacket(r *stack.Route, hdr *buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.TransportProtocolNumber) *tcpip.Error {
 	return tcpip.ErrNotSupported
 }
 
@@ -98,7 +98,7 @@ func (e *endpoint) HandlePacket(r *stack.Route, vv *buffer.VectorisedView) {
 		copy(pkt.HardwareAddressSender(), r.LocalLinkAddress[:])
 		copy(pkt.ProtocolAddressSender(), h.ProtocolAddressTarget())
 		copy(pkt.ProtocolAddressTarget(), h.ProtocolAddressSender())
-		e.linkEP.WritePacket(r, &hdr, nil, ProtocolNumber)
+		e.linkEP.WritePacket(r, &hdr, buffer.VectorisedView{}, ProtocolNumber)
 		fallthrough // also fill the cache from requests
 	case header.ARPReply:
 		addr := tcpip.Address(h.ProtocolAddressSender())
@@ -150,7 +150,7 @@ func (*protocol) LinkAddressRequest(addr, localAddr tcpip.Address, linkEP stack.
 	copy(h.ProtocolAddressSender(), localAddr)
 	copy(h.ProtocolAddressTarget(), addr)
 
-	return linkEP.WritePacket(r, &hdr, nil, ProtocolNumber)
+	return linkEP.WritePacket(r, &hdr, buffer.VectorisedView{}, ProtocolNumber)
 }
 
 // ResolveStaticAddress implements stack.LinkAddressResolver.