OvmfPkg/PvScsiDxe: Open PciIo protocol for later use

This will give us an exclusive access to the PciIo of this device
after it was started and until it will be stopped.

Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=2567
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20200328200100.60786-9-liran.alon@oracle.com>
Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>

OvmfPkg/PvScsiDxe/PvScsi.c

@@ -412,11 +412,23 @@ PvScsiDriverBindingStart (
     return EFI_OUT_OF_RESOURCES;
   }
 
-  Status = PvScsiInit (Dev);
+  Status = gBS->OpenProtocol (
+                  ControllerHandle,
+                  &gEfiPciIoProtocolGuid,
+                  (VOID **)&Dev->PciIo,
+                  This->DriverBindingHandle,
+                  ControllerHandle,
+                  EFI_OPEN_PROTOCOL_BY_DRIVER
+                  );
   if (EFI_ERROR (Status)) {
     goto FreePvScsi;
   }
 
+  Status = PvScsiInit (Dev);
+  if (EFI_ERROR (Status)) {
+    goto ClosePciIo;
+  }
+
   //
   // Setup complete, attempt to export the driver instance's PassThru interface
   //
@@ -436,6 +448,14 @@ PvScsiDriverBindingStart (
 UninitDev:
   PvScsiUninit (Dev);
 
+ClosePciIo:
+  gBS->CloseProtocol (
+         ControllerHandle,
+         &gEfiPciIoProtocolGuid,
+         This->DriverBindingHandle,
+         ControllerHandle
+         );
+
 FreePvScsi:
   FreePool (Dev);
 
@@ -481,6 +501,13 @@ PvScsiDriverBindingStop (
 
   PvScsiUninit (Dev);
 
+  gBS->CloseProtocol (
+         ControllerHandle,
+         &gEfiPciIoProtocolGuid,
+         This->DriverBindingHandle,
+         ControllerHandle
+         );
+
   FreePool (Dev);
 
   return EFI_SUCCESS;

OvmfPkg/PvScsiDxe/PvScsi.h

@@ -19,6 +19,7 @@
 
 typedef struct {
   UINT32                          Signature;
+  EFI_PCI_IO_PROTOCOL             *PciIo;
   UINT8                           MaxTarget;
   UINT8                           MaxLun;
   EFI_EXT_SCSI_PASS_THRU_PROTOCOL PassThru;