From 6fb8ddd36bde45614b0a069528cdc97077835a74 Mon Sep 17 00:00:00 2001
From: Laszlo Ersek <lersek@redhat.com>
Date: Sun, 3 Sep 2017 15:21:59 +0200
Subject: [PATCH] MdeModulePkg/AtaAtapiPassThru: disable the device at
 ExitBootServices()

The AtaAtapiPassThru driver maps three system memory regions for Bus
Master Common Buffer operation on the following call path, if the
controller has PCI_CLASS_MASS_STORAGE_SATADPA class code:

  AtaAtapiPassThruStart()
    EnumerateAttachedDevice()
      AhciModeInitialization()
        AhciCreateTransferDescriptor()

The device is disabled (including Bus Master DMA) when the controller is
unbound, in AtaAtapiPassThruStop(). Then the regions are unmapped.

The former step should also be done when we exit the boot services, and
the OS gains ownership of system memory.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 .../Ata/AtaAtapiPassThru/AtaAtapiPassThru.c   | 59 ++++++++++++++++++-
 .../Ata/AtaAtapiPassThru/AtaAtapiPassThru.h   |  6 ++
 2 files changed, 64 insertions(+), 1 deletion(-)

diff --git a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AtaAtapiPassThru.c b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AtaAtapiPassThru.c
index a48b295d26..09064dda18 100644
--- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AtaAtapiPassThru.c
+++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AtaAtapiPassThru.c
@@ -104,7 +104,8 @@ ATA_ATAPI_PASS_THRU_INSTANCE gAtaAtapiPassThruInstanceTemplate = {
   {                   // NonBlocking TaskList
     NULL,
     NULL
-  }
+  },
+  NULL,               // ExitBootEvent
 };
 
 ATAPI_DEVICE_PATH    mAtapiDevicePathTemplate = {
@@ -478,6 +479,38 @@ InitializeAtaAtapiPassThru (
   return Status;
 }
 
+/**
+  Disable the device (especially Bus Master DMA) when exiting the boot
+  services.
+
+  @param[in] Event    Event for which this notification function is being
+                      called.
+  @param[in] Context  Pointer to the ATA_ATAPI_PASS_THRU_INSTANCE that
+                      represents the HBA.
+**/
+VOID
+EFIAPI
+AtaPassThruExitBootServices (
+  IN EFI_EVENT Event,
+  IN VOID      *Context
+  )
+{
+  ATA_ATAPI_PASS_THRU_INSTANCE *Instance;
+  EFI_PCI_IO_PROTOCOL          *PciIo;
+
+  DEBUG ((DEBUG_VERBOSE, "%a: Context=0x%p\n", __FUNCTION__, Context));
+
+  Instance = Context;
+  PciIo = Instance->PciIo;
+
+  PciIo->Attributes (
+           PciIo,
+           EfiPciIoAttributeOperationDisable,
+           Instance->EnabledPciAttributes,
+           NULL
+           );
+}
+
 /**
   Tests to see if this driver supports a given controller. If a child device is provided,
   it further tests to see if this driver supports creating a handle for the specified child device.
@@ -757,6 +790,17 @@ AtaAtapiPassThruStart (
   InitializeListHead(&Instance->DeviceList);
   InitializeListHead(&Instance->NonBlockingTaskList);
 
+  Status = gBS->CreateEvent (
+                  EVT_SIGNAL_EXIT_BOOT_SERVICES,
+                  TPL_CALLBACK,
+                  AtaPassThruExitBootServices,
+                  Instance,
+                  &Instance->ExitBootEvent
+                  );
+  if (EFI_ERROR (Status)) {
+    goto ErrorExit;
+  }
+
   Instance->TimerEvent = NULL;
 
   Status = gBS->CreateEvent (
@@ -810,6 +854,10 @@ ErrorExit:
     gBS->CloseEvent (Instance->TimerEvent);
   }
 
+  if ((Instance != NULL) && (Instance->ExitBootEvent != NULL)) {
+    gBS->CloseEvent (Instance->ExitBootEvent);
+  }
+
   //
   // Remove all inserted ATA devices.
   //
@@ -908,6 +956,15 @@ AtaAtapiPassThruStop (
     Instance->TimerEvent = NULL;
   }
   DestroyAsynTaskList (Instance, FALSE);
+
+  //
+  // Close event signaled at gBS->ExitBootServices().
+  //
+  if (Instance->ExitBootEvent != NULL) {
+    gBS->CloseEvent (Instance->ExitBootEvent);
+    Instance->ExitBootEvent = NULL;
+  }
+
   //
   // Free allocated resource
   //
diff --git a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AtaAtapiPassThru.h b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AtaAtapiPassThru.h
index 85e5a55539..8d6eac706c 100644
--- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AtaAtapiPassThru.h
+++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AtaAtapiPassThru.h
@@ -121,6 +121,12 @@ typedef struct {
   //
   EFI_EVENT                         TimerEvent;
   LIST_ENTRY                        NonBlockingTaskList;
+
+  //
+  // For disabling the device (especially Bus Master DMA) at
+  // ExitBootServices().
+  //
+  EFI_EVENT                         ExitBootEvent;
 } ATA_ATAPI_PASS_THRU_INSTANCE;
 
 //
-- 
2.39.2