From 350e03f04187525f43b53c032465d375516f33bf Mon Sep 17 00:00:00 2001
From: Jinjun Gao <gjinjun@gmail.com>
Date: Sun, 2 Jan 2022 23:43:12 +0800
Subject: [PATCH] Enable set_field with Metadata register

WriteMetadata is write-action instruction which will be applied later
than apply-action. In some case, we need use resubmit to do pipeline in
the same table and set Metadata before resubmit at the same time.
WriteMetadata cannot do the job. We need enable set_field for Metadata
register.

Actually, WriteMetadata do the same thing with set_field Metadata
register in the OvS. From OpenFlow 1.5, Metadata register also can be
used with set_field to set, not stricted only using WriteMetadata instruction.

After this patch, ofnet can support WriteMetadata and set_field for
Metadata meanwhile. Caller can use SetMetadata() or WriteMetadata() API
to implement WriteMetadata action, and use SetMetadataAction() and
ApplyAction() to implement set_field for Metadata.

Signed-off-by: Jinjun Gao <gjinjun@gmail.com>
---
 VERSION              |  2 +-
 ofctrl/fgraphFlow.go | 17 +++++++++++------
 ofctrl/ofAction.go   | 17 ++++++++++++++++-
 3 files changed, 28 insertions(+), 8 deletions(-)

diff --git a/VERSION b/VERSION
index 62291ae2..1b0ae03b 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-v0.5.7
+v0.5.8
diff --git a/ofctrl/fgraphFlow.go b/ofctrl/fgraphFlow.go
index 0a3c9b4b..3bdedc89 100644
--- a/ofctrl/fgraphFlow.go
+++ b/ofctrl/fgraphFlow.go
@@ -98,7 +98,7 @@ type FlowMatch struct {
 
 // additional Actions in flow's instruction set
 type FlowAction struct {
-	ActionType    string               // Type of action "setVlan", "setMetadata"
+	ActionType    string               // Type of action "setVlan", "writeMetadata"
 	vlanId        uint16               // Vlan Id in case of "setVlan"
 	macAddr       net.HardwareAddr     // Mac address to set
 	mplsEtherType uint16               // mpls ether type to push or pop
@@ -106,7 +106,7 @@ type FlowAction struct {
 	l4Port        uint16               // Transport port to be set
 	arpOper       uint16               // Arp operation type to be set
 	tunnelId      uint64               // Tunnel Id (used for setting VNI)
-	metadata      uint64               // Metadata in case of "setMetadata"
+	metadata      uint64               // Metadata in case of "writeMetadata"
 	metadataMask  uint64               // Metadata mask
 	dscp          uint8                // DSCP field
 	loadAct       *NXLoadAction        // Load data into OXM/NXM fields, one or more Actions
@@ -843,12 +843,13 @@ func (self *Flow) installFlowActions(flowMod *openflow13.FlowMod,
 
 			log.Debugf("flow install. Added setTunnelId Action: %+v", setTunnelAction)
 
-		case "setMetadata":
-			// Set Metadata instruction
+		case ActTypeWriteMetadata:
+			// Write Metadata instruction
 			metadataInstr := openflow13.NewInstrWriteMetadata(flowAction.metadata, flowAction.metadataMask)
 
 			// Add the instruction to flowmod
 			flowMod.AddInstruction(metadataInstr)
+			log.Debugf("flow install. Added writeMetadata Action: %+v", metadataInstr)
 
 		case ActTypeSetSrcIP:
 			// Set IP src
@@ -1584,10 +1585,14 @@ func (self *Flow) SetL4Field(port uint16, field string) error {
 	return nil
 }
 
-// Special actions on the flow to set metadata
+// Special actions on the flow to write metadata.
+// By using this API, it will call `writeMetadata' instruction
+// to write metadata register in installFlowActions().
+// Instead, you can also use SetMetadataAction which uses
+// `set_field' to write metadata register.
 func (self *Flow) SetMetadata(metadata, metadataMask uint64) error {
 	action := new(FlowAction)
-	action.ActionType = "setMetadata"
+	action.ActionType = ActTypeWriteMetadata
 	action.metadata = metadata
 	action.metadataMask = metadataMask
 
diff --git a/ofctrl/ofAction.go b/ofctrl/ofAction.go
index 14dcabbb..999c9d34 100644
--- a/ofctrl/ofAction.go
+++ b/ofctrl/ofAction.go
@@ -17,7 +17,8 @@ const (
 	ActTypeSetDstMac      = "setMacDa"
 	ActTypeSetSrcMac      = "setMacSa"
 	ActTypeSetTunnelID    = "setTunnelId"
-	ActTypeMetatdata      = "setMetadata"
+	ActTypeSetMetadata    = "setMetadata"   // use set_field
+	ActTypeWriteMetadata  = "writeMetadata" // use writeMetadata instruction
 	ActTypeSetSrcIP       = "setIPSa"
 	ActTypeSetDstIP       = "setIPDa"
 	ActTypeSetTunnelSrcIP = "setTunSa"
@@ -160,6 +161,20 @@ func (a *SetTunnelIDAction) GetActionType() string {
 	return ActTypeSetTunnelID
 }
 
+type SetMetadataAction struct {
+	Metadata     uint64
+	MetadataMask *uint64
+}
+
+func (a *SetMetadataAction) GetActionMessage() openflow13.Action {
+	field := openflow13.NewMetadataField(a.Metadata, a.MetadataMask)
+	return openflow13.NewActionSetField(*field)
+}
+
+func (a *SetMetadataAction) GetActionType() string {
+	return ActTypeSetMetadata
+}
+
 type SetTunnelDstAction struct {
 	IP net.IP
 }