[Patch] NetworkPkg/IScsiDxe: Switch IP4 configuration policy to Static before DHCP

[Jiaxin Wu <jiaxin.wu@intel.com>]

DHCP4 service allows only one of its children to be configured in the active
state. If the DHCP4 D.O.R.A started by IP4 auto configuration and has not
been completed, the Dhcp4 state machine will not be in the right state for
the iSCSI to start a new round D.O.R.A. So, we need to switch it's policy to
static.

Cc: Ye Ting <ting.ye@intel.com>
Cc: Fu Siyuan <siyuan.fu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Wu Jiaxin <jiaxin.wu@intel.com>
---
 NetworkPkg/IScsiDxe/IScsiDhcp.c | 61 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)

diff --git a/NetworkPkg/IScsiDxe/IScsiDhcp.c b/NetworkPkg/IScsiDxe/IScsiDhcp.c
index 43ae50b..6587a05 100644
--- a/NetworkPkg/IScsiDxe/IScsiDhcp.c
+++ b/NetworkPkg/IScsiDxe/IScsiDhcp.c
@@ -369,10 +369,54 @@ IScsiParseDhcpAck (
   FreePool (OptionList);
 
   return Status;
 }
 
+/**
+  This function will switch the IP4 configuration policy to Static.
+
+  @param[in]  Ip4Config2          Pointer to the IP4 configuration protocol.
+
+  @retval     EFI_SUCCESS         The policy is already configured to static.
+  @retval     Others              Other error as indicated.
+
+**/
+EFI_STATUS
+IScsiSetIp4Policy (
+  IN EFI_IP4_CONFIG2_PROTOCOL        *Ip4Config2
+  )
+{
+  EFI_IP4_CONFIG2_POLICY          Policy;
+  EFI_STATUS                      Status;
+  UINTN                           DataSize;
+
+  DataSize = sizeof (EFI_IP4_CONFIG2_POLICY);
+  Status = Ip4Config2->GetData (
+                         Ip4Config2,
+                         Ip4Config2DataTypePolicy,
+                         &DataSize,
+                         &Policy
+                         );
+  if (EFI_ERROR (Status)) {
+    return Status;
+  }
+
+  if (Policy != Ip4Config2PolicyStatic) {
+    Policy = Ip4Config2PolicyStatic;
+    Status= Ip4Config2->SetData (
+                          Ip4Config2,
+                          Ip4Config2DataTypePolicy,
+                          sizeof (EFI_IP4_CONFIG2_POLICY),
+                          &Policy
+                          );
+    if (EFI_ERROR (Status)) {
+      return Status;
+    } 
+  }
+
+  return EFI_SUCCESS;
+}
 
 /**
   Parse the DHCP ACK to get the address configuration and DNS information.
 
   @param[in]       Image            The handle of the driver image.
@@ -391,18 +435,20 @@ IScsiDoDhcp (
   IN     EFI_HANDLE                  Controller,
   IN OUT ISCSI_ATTEMPT_CONFIG_NVDATA *ConfigData
   )
 {
   EFI_HANDLE                    Dhcp4Handle;
+  EFI_IP4_CONFIG2_PROTOCOL      *Ip4Config2;
   EFI_DHCP4_PROTOCOL            *Dhcp4;
   EFI_STATUS                    Status;
   EFI_DHCP4_PACKET_OPTION       *ParaList;
   EFI_DHCP4_CONFIG_DATA         Dhcp4ConfigData;
   ISCSI_SESSION_CONFIG_NVDATA   *NvData;
   BOOLEAN                       MediaPresent;
 
   Dhcp4Handle = NULL;
+  Ip4Config2  = NULL;
   Dhcp4       = NULL;
   ParaList    = NULL;
 
   //
   // Check media status before doing DHCP.
@@ -412,10 +458,25 @@ IScsiDoDhcp (
   if (!MediaPresent) {
     return EFI_NO_MEDIA;
   }
 
   //
+  // DHCP4 service allows only one of its children to be configured in  
+  // the active state, If the DHCP4 D.O.R.A started by IP4 auto  
+  // configuration and has not been completed, the Dhcp4 state machine 
+  // will not be in the right state for the iSCSI to start a new round D.O.R.A. 
+  // So, we need to switch it's policy to static.
+  //
+  Status = gBS->HandleProtocol (Controller, &gEfiIp4Config2ProtocolGuid, (VOID **) &Ip4Config2);
+  if (!EFI_ERROR (Status)) {
+    Status = IScsiSetIp4Policy (Ip4Config2);
+    if (EFI_ERROR (Status)) {
+      return Status;
+    }
+  }
+
+  //
   // Create a DHCP4 child instance and get the protocol.
   //
   Status = NetLibCreateServiceChild (
              Controller,
              Image,
-- 
1.9.5.msysgit.1