From b0338c53297cfbabd727f36c4878379c86cf4ddc Mon Sep 17 00:00:00 2001
From: Brijesh Singh <brijesh.singh@amd.com>
Date: Wed, 23 Aug 2017 06:57:18 -0400
Subject: [PATCH] OvmfPkg/VirtioLib: alloc VRING buffer with
 AllocateSharedPages()

The VRING buffer is a communication area between guest and hypervisor.
Allocate it using VIRTIO_DEVICE_PROTOCOL.AllocateSharedPages() so that
it can be mapped later with VirtioRingMap() for bi-directional access.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
[lersek@redhat.com: correct typo in VirtioRingInit() comment blocks]
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
---
 OvmfPkg/Include/Library/VirtioLib.h     |  5 ++---
 OvmfPkg/Library/VirtioLib/VirtioLib.c   | 22 ++++++++++++++--------
 OvmfPkg/Library/VirtioLib/VirtioLib.inf |  1 -
 3 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/OvmfPkg/Include/Library/VirtioLib.h b/OvmfPkg/Include/Library/VirtioLib.h
index 6a422deba2..547b4ee497 100644
--- a/OvmfPkg/Include/Library/VirtioLib.h
+++ b/OvmfPkg/Include/Library/VirtioLib.h
@@ -42,9 +42,8 @@
 
   @param[out] Ring              The virtio ring to set up.
 
-  @retval EFI_OUT_OF_RESOURCES  AllocatePages() failed to allocate contiguous
-                                pages for the requested QueueSize. Fields of
-                                Ring have indeterminate value.
+  @return                       Status codes propagated from
+                                VirtIo->AllocateSharedPages().
 
   @retval EFI_SUCCESS           Allocation and setup successful. Ring->Base
                                 (and nothing else) is responsible for
diff --git a/OvmfPkg/Library/VirtioLib/VirtioLib.c b/OvmfPkg/Library/VirtioLib/VirtioLib.c
index 84acfe6183..40ea17dfaf 100644
--- a/OvmfPkg/Library/VirtioLib/VirtioLib.c
+++ b/OvmfPkg/Library/VirtioLib/VirtioLib.c
@@ -19,7 +19,6 @@
 #include <Library/BaseLib.h>
 #include <Library/BaseMemoryLib.h>
 #include <Library/DebugLib.h>
-#include <Library/MemoryAllocationLib.h>
 #include <Library/UefiBootServicesTableLib.h>
 
 #include <Library/VirtioLib.h>
@@ -44,9 +43,8 @@
 
   @param[out] Ring              The virtio ring to set up.
 
-  @retval EFI_OUT_OF_RESOURCES  AllocatePages() failed to allocate contiguous
-                                pages for the requested QueueSize. Fields of
-                                Ring have indeterminate value.
+  @return                       Status codes propagated from
+                                VirtIo->AllocateSharedPages().
 
   @retval EFI_SUCCESS           Allocation and setup successful. Ring->Base
                                 (and nothing else) is responsible for
@@ -61,6 +59,7 @@ VirtioRingInit (
   OUT VRING                  *Ring
   )
 {
+  EFI_STATUS     Status;
   UINTN          RingSize;
   volatile UINT8 *RingPagesPtr;
 
@@ -79,10 +78,17 @@ VirtioRingInit (
                 sizeof *Ring->Used.AvailEvent,
                 EFI_PAGE_SIZE);
 
+  //
+  // Allocate a shared ring buffer
+  //
   Ring->NumPages = EFI_SIZE_TO_PAGES (RingSize);
-  Ring->Base = AllocatePages (Ring->NumPages);
-  if (Ring->Base == NULL) {
-    return EFI_OUT_OF_RESOURCES;
+  Status = VirtIo->AllocateSharedPages (
+                     VirtIo,
+                     Ring->NumPages,
+                     &Ring->Base
+                     );
+  if (EFI_ERROR (Status)) {
+    return Status;
   }
   SetMem (Ring->Base, RingSize, 0x00);
   RingPagesPtr = Ring->Base;
@@ -143,7 +149,7 @@ VirtioRingUninit (
   IN OUT VRING                  *Ring
   )
 {
-  FreePages (Ring->Base, Ring->NumPages);
+  VirtIo->FreeSharedPages (VirtIo, Ring->NumPages, Ring->Base);
   SetMem (Ring, sizeof *Ring, 0x00);
 }
 
diff --git a/OvmfPkg/Library/VirtioLib/VirtioLib.inf b/OvmfPkg/Library/VirtioLib/VirtioLib.inf
index fb5897a88e..e33856de38 100644
--- a/OvmfPkg/Library/VirtioLib/VirtioLib.inf
+++ b/OvmfPkg/Library/VirtioLib/VirtioLib.inf
@@ -32,5 +32,4 @@
   BaseLib
   BaseMemoryLib
   DebugLib
-  MemoryAllocationLib
   UefiBootServicesTableLib