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>

2 files changed, 14 insertions, 9 deletions

diff --git a/OvmfPkg/Library/VirtioLib/VirtioLib.c b/OvmfPkg/Library/VirtioLib/VirtioLib.c
index 84acfe6..40ea17d 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 fb5897a..e33856d 100644
--- a/OvmfPkg/Library/VirtioLib/VirtioLib.inf
+++ b/OvmfPkg/Library/VirtioLib/VirtioLib.inf
@@ -32,5 +32,4 @@
   BaseLib

   BaseMemoryLib

   DebugLib

-  MemoryAllocationLib

   UefiBootServicesTableLib