OvmfPkg: VirtioBlkDxe: reset device at ExitBootServices()

[mirror_edk2.git] / OvmfPkg / VirtioBlkDxe / VirtioBlk.c

diff --git a/OvmfPkg/VirtioBlkDxe/VirtioBlk.c b/OvmfPkg/VirtioBlkDxe/VirtioBlk.c
index 862957ce04448467534c8d4c26e73c768881cd66..75f85ca6e09ad01fdadf8bc3245596c8cac45873 100644 (file)
--- a/OvmfPkg/VirtioBlkDxe/VirtioBlk.c
+++ b/OvmfPkg/VirtioBlkDxe/VirtioBlk.c
@@ -841,6 +841,37 @@ VirtioBlkUninit (
 }\r
 \r
 \r
+/**\r
+\r
+  Event notification function enqueued by ExitBootServices().\r
+\r
+  @param[in] Event    Event whose notification function is being invoked.\r
+\r
+  @param[in] Context  Pointer to the VBLK_DEV structure.\r
+\r
+**/\r
+\r
+STATIC\r
+VOID\r
+EFIAPI\r
+VirtioBlkExitBoot (\r
+  IN  EFI_EVENT Event,\r
+  IN  VOID      *Context\r
+  )\r
+{\r
+  VBLK_DEV *Dev;\r
+\r
+  //\r
+  // Reset the device. This causes the hypervisor to forget about the virtio\r
+  // ring.\r
+  //\r
+  // We allocated said ring in EfiBootServicesData type memory, and code\r
+  // executing after ExitBootServices() is permitted to overwrite it.\r
+  //\r
+  Dev = Context;\r
+  Dev->VirtIo->SetDeviceStatus (Dev->VirtIo, 0);\r
+}\r
+\r
 /**\r
 \r
   After we've pronounced support for a specific device in\r
@@ -901,6 +932,12 @@ VirtioBlkDriverBindingStart (
     goto CloseVirtIo;\r
   }\r
 \r
+  Status = gBS->CreateEvent (EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_CALLBACK,\r
+                  &VirtioBlkExitBoot, Dev, &Dev->ExitBoot);\r
+  if (EFI_ERROR (Status)) {\r
+    goto UninitDev;\r
+  }\r
+\r
   //\r
   // Setup complete, attempt to export the driver instance's BlockIo interface.\r
   //\r
@@ -909,11 +946,14 @@ VirtioBlkDriverBindingStart (
                   &gEfiBlockIoProtocolGuid, EFI_NATIVE_INTERFACE,\r
                   &Dev->BlockIo);\r
   if (EFI_ERROR (Status)) {\r
-    goto UninitDev;\r
+    goto CloseExitBoot;\r
   }\r
 \r
   return EFI_SUCCESS;\r
 \r
+CloseExitBoot:\r
+  gBS->CloseEvent (Dev->ExitBoot);\r
+\r
 UninitDev:\r
   VirtioBlkUninit (Dev);\r
 \r
@@ -987,6 +1027,8 @@ VirtioBlkDriverBindingStop (
     return Status;\r
   }\r
 \r
+  gBS->CloseEvent (Dev->ExitBoot);\r
+\r
   VirtioBlkUninit (Dev);\r
 \r
   gBS->CloseProtocol (DeviceHandle, &gVirtioDeviceProtocolGuid,\r