OvmfPkg/XenBusDxe: Add support to make Xen Hypercalls.

Change in V4:
- Replace the license by the commonly used file header text.
- add file header to XenHypercall.h (license, copyright, brief desc)

Change in V3:
- adding IA32 support. (not reviewed yet)
  both XenBusDxe/Ia32/hypercall.{S,asm} file are new

Change in V2:
- file header, copyright
- Add License
- Add push/pop instruction.
- fix types
- Comment of exported functions
- Improve coding style
- Add error handling in the main init function (of the drivers)
- Comment assembly

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16260 6f19259b-4bc3-4df7-8a09-765794883524

9 files changed, 362 insertions, 0 deletions

diff --git a/OvmfPkg/XenBusDxe/Ia32/hypercall.S b/OvmfPkg/XenBusDxe/Ia32/hypercall.S
new file mode 100644
index 0000000000..77d3478475
--- /dev/null
+++ b/OvmfPkg/XenBusDxe/Ia32/hypercall.S
@@ -0,0 +1,22 @@
+# INTN

+# EFIAPI

+# XenHypercall2 (

+#   IN     VOID *HypercallAddr,

+#   IN OUT INTN Arg1,

+#   IN OUT INTN Arg2

+#   );

+ASM_GLOBAL ASM_PFX(XenHypercall2)

+ASM_PFX(XenHypercall2):

+  # Save only ebx, ecx is supposed to be a scratch register and needs to be

+  # saved by the caller

+  push %ebx

+  # Copy HypercallAddr to eax

+  mov 8(%esp), %eax

+  # Copy Arg1 to the register expected by Xen

+  mov 12(%esp), %ebx

+  # Copy Arg2 to the register expected by Xen

+  mov 16(%esp), %ecx

+  # Call HypercallAddr

+  call *%eax

+  pop %ebx

+  ret

diff --git a/OvmfPkg/XenBusDxe/Ia32/hypercall.asm b/OvmfPkg/XenBusDxe/Ia32/hypercall.asm
new file mode 100644
index 0000000000..9ead740f91
--- /dev/null
+++ b/OvmfPkg/XenBusDxe/Ia32/hypercall.asm
@@ -0,0 +1,26 @@
+.code

+

+; INTN

+; EFIAPI

+; XenHypercall2 (

+;   IN     VOID *HypercallAddr,

+;   IN OUT INTN Arg1,

+;   IN OUT INTN Arg2

+;   );

+XenHypercall2 PROC

+  ; Save only ebx, ecx is supposed to be a scratch register and needs to be

+  ; saved by the caller

+  push ebx

+  ; Copy HypercallAddr to eax

+  mov eax, [esp + 8]

+  ; Copy Arg1 to the register expected by Xen

+  mov ebx, [esp + 12]

+  ; Copy Arg2 to the register expected by Xen

+  mov ecx, [esp + 16]

+  ; Call HypercallAddr

+  call eax

+  pop ebx

+  ret

+XenHypercall2 ENDP

+

+END

diff --git a/OvmfPkg/XenBusDxe/X64/hypercall.S b/OvmfPkg/XenBusDxe/X64/hypercall.S
new file mode 100644
index 0000000000..83cf466953
--- /dev/null
+++ b/OvmfPkg/XenBusDxe/X64/hypercall.S
@@ -0,0 +1,22 @@
+# INTN

+# EFIAPI

+# XenHypercall2 (

+#   IN     VOID *HypercallAddr,

+#   IN OUT INTN Arg1,

+#   IN OUT INTN Arg2

+#   );

+ASM_GLOBAL ASM_PFX(XenHypercall2)

+ASM_PFX(XenHypercall2):

+  push %rdi

+  push %rsi

+  # Copy HypercallAddr to rax

+  movq %rcx, %rax

+  # Copy Arg1 to the register expected by Xen

+  movq %rdx, %rdi

+  # Copy Arg2 to the register expected by Xen

+  movq %r8, %rsi

+  # Call HypercallAddr

+  call *%rax

+  pop %rsi

+  pop %rdi

+  ret

diff --git a/OvmfPkg/XenBusDxe/X64/hypercall.asm b/OvmfPkg/XenBusDxe/X64/hypercall.asm
new file mode 100644
index 0000000000..5b3451473d
--- /dev/null
+++ b/OvmfPkg/XenBusDxe/X64/hypercall.asm
@@ -0,0 +1,26 @@
+.code

+

+; INTN

+; EFIAPI

+; XenHypercall2 (

+;   IN     VOID *HypercallAddr,

+;   IN OUT INTN Arg1,

+;   IN OUT INTN Arg2

+;   );

+XenHypercall2 PROC

+  push rdi

+  push rsi

+  ; Copy HypercallAddr to rax

+  mov rax, rcx

+  ; Copy Arg1 to the register expected by Xen

+  mov rdi, rdx

+  ; Copy Arg2 to the register expected by Xen

+  mov rsi, r8

+  ; Call HypercallAddr

+  call rax

+  pop rsi

+  pop rdi

+  ret

+XenHypercall2 ENDP

+

+END

diff --git a/OvmfPkg/XenBusDxe/XenBusDxe.c b/OvmfPkg/XenBusDxe/XenBusDxe.c
index f3c74e1fbe..4c638b85f1 100644
--- a/OvmfPkg/XenBusDxe/XenBusDxe.c
+++ b/OvmfPkg/XenBusDxe/XenBusDxe.c
@@ -29,6 +29,8 @@
 

 #include "XenBusDxe.h"

 

+#include "XenHypercall.h"

+

 

 ///

 /// Driver Binding Protocol instance

@@ -264,6 +266,8 @@ NotifyExitBoot (
   @retval EFI_SUCCESS              The device was started.

   @retval EFI_DEVICE_ERROR         The device could not be started due to a device error.Currently not implemented.

   @retval EFI_OUT_OF_RESOURCES     The request could not be completed due to a lack of resources.

+  @retval EFI_UNSUPPORTED          Something is missing on the system that

+                                   prevent to start the edvice.

   @retval Others                   The driver failded to start the device.

 

 **/

@@ -295,6 +299,20 @@ XenBusDxeDriverBindingStart (
   mMyDevice = Dev;

   EfiReleaseLock (&mMyDeviceLock);

 

+  Status = XenHyperpageInit (Dev);

+  if (EFI_ERROR (Status)) {

+    DEBUG ((EFI_D_ERROR, "XenBus: Unable to retrieve the hyperpage.\n"));

+    Status = EFI_UNSUPPORTED;

+    goto ErrorAllocated;

+  }

+

+  Status = XenGetSharedInfoPage (Dev);

+  if (EFI_ERROR (Status)) {

+    DEBUG ((EFI_D_ERROR, "XenBus: Unable to get the shared info page.\n"));

+    Status = EFI_UNSUPPORTED;

+    goto ErrorAllocated;

+  }

+

   Status = gBS->CreateEvent (EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_CALLBACK,

                              NotifyExitBoot,

                              (VOID*) Dev,

diff --git a/OvmfPkg/XenBusDxe/XenBusDxe.h b/OvmfPkg/XenBusDxe/XenBusDxe.h
index d7537f3fe5..ccec0ce0e5 100644
--- a/OvmfPkg/XenBusDxe/XenBusDxe.h
+++ b/OvmfPkg/XenBusDxe/XenBusDxe.h
@@ -70,6 +70,8 @@ extern EFI_COMPONENT_NAME_PROTOCOL  gXenBusDxeComponentName;
 //

 // Other stuff

 //

+#include <IndustryStandard/Xen/xen.h>

+

 #define PCI_VENDOR_ID_XEN                0x5853

 #define PCI_DEVICE_ID_XEN_PLATFORM       0x0001

 

@@ -83,6 +85,9 @@ struct _XENBUS_DEVICE {
   EFI_DRIVER_BINDING_PROTOCOL   *This;

   EFI_HANDLE                    ControllerHandle;

   EFI_EVENT                     ExitBootEvent;

+

+  VOID                          *Hyperpage;

+  shared_info_t                 *SharedInfo;

 };

 

 #endif

diff --git a/OvmfPkg/XenBusDxe/XenBusDxe.inf b/OvmfPkg/XenBusDxe/XenBusDxe.inf
index fb63ec251e..6da3d2d670 100644
--- a/OvmfPkg/XenBusDxe/XenBusDxe.inf
+++ b/OvmfPkg/XenBusDxe/XenBusDxe.inf
@@ -34,6 +34,16 @@
   DriverBinding.h

   ComponentName.c

   ComponentName.h

+  XenHypercall.c

+  XenHypercall.h

+

+[Sources.IA32]

+  Ia32/hypercall.S

+  Ia32/hypercall.asm

+

+[Sources.X64]

+  X64/hypercall.S

+  X64/hypercall.asm

 

 [LibraryClasses]

   UefiDriverEntryPoint

diff --git a/OvmfPkg/XenBusDxe/XenHypercall.c b/OvmfPkg/XenBusDxe/XenHypercall.c
new file mode 100644
index 0000000000..0f2ba5d693
--- /dev/null
+++ b/OvmfPkg/XenBusDxe/XenHypercall.c
@@ -0,0 +1,118 @@
+/** @file

+  Functions to make Xen hypercalls.

+

+  Copyright (C) 2014, Citrix Ltd.

+

+  This program and the accompanying materials

+  are licensed and made available under the terms and conditions of the BSD License

+  which accompanies this distribution.  The full text of the license may be found at

+  http://opensource.org/licenses/bsd-license.php

+

+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,

+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

+

+**/

+

+#include <PiDxe.h>

+#include <Library/HobLib.h>

+#include <Guid/XenInfo.h>

+

+#include "XenBusDxe.h"

+#include "XenHypercall.h"

+

+#include <IndustryStandard/Xen/hvm/params.h>

+#include <IndustryStandard/Xen/memory.h>

+

+EFI_STATUS

+XenHyperpageInit (

+  IN OUT XENBUS_DEVICE *Dev

+  )

+{

+  EFI_HOB_GUID_TYPE   *GuidHob;

+  EFI_XEN_INFO        *XenInfo;

+

+  GuidHob = GetFirstGuidHob (&gEfiXenInfoGuid);

+  if (GuidHob == NULL) {

+    return EFI_NOT_FOUND;

+  }

+  XenInfo = (EFI_XEN_INFO *) GET_GUID_HOB_DATA (GuidHob);

+  Dev->Hyperpage = XenInfo->HyperPages;

+  return EFI_SUCCESS;

+}

+

+UINT64

+XenHypercallHvmGetParam (

+  IN XENBUS_DEVICE *Dev,

+  IN INTN          Index

+  )

+{

+  xen_hvm_param_t     Parameter;

+  INTN                Error;

+

+  ASSERT (Dev->Hyperpage != NULL);

+

+  Parameter.domid = DOMID_SELF;

+  Parameter.index = Index;

+  Error = XenHypercall2 (Dev->Hyperpage + __HYPERVISOR_hvm_op * 32,

+                         HVMOP_get_param, (INTN) &Parameter);

+  if (Error != 0) {

+    DEBUG ((EFI_D_ERROR,

+            "XenHypercall: Error %d trying to get HVM parameter %d\n",

+            Error, Index));

+    return 0;

+  }

+  return Parameter.value;

+}

+

+INTN

+XenHypercallMemoryOp (

+  IN     XENBUS_DEVICE *Dev,

+  IN     UINTN Operation,

+  IN OUT VOID *Arguments

+  )

+{

+  ASSERT (Dev->Hyperpage != NULL);

+  return XenHypercall2 (Dev->Hyperpage + __HYPERVISOR_memory_op * 32,

+                        Operation, (INTN) Arguments);

+}

+

+INTN

+XenHypercallEventChannelOp (

+  IN     XENBUS_DEVICE *Dev,

+  IN     INTN Operation,

+  IN OUT VOID *Arguments

+  )

+{

+  ASSERT (Dev->Hyperpage != NULL);

+  return XenHypercall2 (Dev->Hyperpage + __HYPERVISOR_event_channel_op * 32,

+                        Operation, (INTN) Arguments);

+}

+

+EFI_STATUS

+XenGetSharedInfoPage (

+  IN OUT XENBUS_DEVICE *Dev

+  )

+{

+  xen_add_to_physmap_t Parameter;

+

+  ASSERT (Dev->SharedInfo == NULL);

+

+  Parameter.domid = DOMID_SELF;

+  Parameter.space = XENMAPSPACE_shared_info;

+  Parameter.idx = 0;

+

+  //

+  // using reserved page because the page is not released when Linux is

+  // starting because of the add_to_physmap. QEMU might try to access the

+  // page, and fail because it have no right to do so (segv).

+  //

+  Dev->SharedInfo = AllocateReservedPages (1);

+  Parameter.gpfn = (UINTN) Dev->SharedInfo >> EFI_PAGE_SHIFT;

+  if (XenHypercallMemoryOp (Dev, XENMEM_add_to_physmap, &Parameter) != 0) {

+    FreePages (Dev->SharedInfo, 1);

+    Dev->SharedInfo = NULL;

+    return EFI_LOAD_ERROR;

+  }

+

+  return EFI_SUCCESS;

+}

diff --git a/OvmfPkg/XenBusDxe/XenHypercall.h b/OvmfPkg/XenBusDxe/XenHypercall.h
new file mode 100644
index 0000000000..3627b1886c
--- /dev/null
+++ b/OvmfPkg/XenBusDxe/XenHypercall.h
@@ -0,0 +1,115 @@
+/** @file

+  Functions declarations to make Xen hypercalls.

+

+  Copyright (C) 2014, Citrix Ltd.

+

+  This program and the accompanying materials

+  are licensed and made available under the terms and conditions of the BSD License

+  which accompanies this distribution.  The full text of the license may be found at

+  http://opensource.org/licenses/bsd-license.php

+

+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,

+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

+

+**/

+

+#ifndef __XENBUS_DXE_HYPERCALL_H__

+#define __XENBUS_DXE_HYPERCALL_H__

+

+typedef struct _XENBUS_DEVICE XENBUS_DEVICE;

+

+/**

+  This function will put the two arguments in the right place (registers) and

+  call HypercallAddr, which correspond to an entry in the hypercall pages.

+

+  @param HypercallAddr  A memory address where the hypercall to call is.

+  @param Arg1           First argument.

+  @param Arg2           Second argument.

+

+  @return   Return 0 if success otherwise it return an errno.

+**/

+INTN

+EFIAPI

+XenHypercall2 (

+  IN     VOID *HypercallAddr,

+  IN OUT INTN Arg1,

+  IN OUT INTN Arg2

+  );

+

+/**

+  Get the page where all hypercall are from the XenInfo hob.

+

+  @param Dev    A XENBUS_DEVICE instance.

+

+  @retval EFI_NOT_FOUND   hyperpage could not be found.

+  @retval EFI_SUCCESS     Successfully retrieve the hyperpage pointer.

+**/

+EFI_STATUS

+XenHyperpageInit (

+  XENBUS_DEVICE *Dev

+  );

+

+/**

+  Return the value of the HVM parameter Index.

+

+  @param Dev    A XENBUS_DEVICE instance.

+  @param Index  The parameter to get, e.g. HVM_PARAM_STORE_EVTCHN.

+

+  @return   The value of the asked parameter or 0 in case of error.

+**/

+UINT64

+XenHypercallHvmGetParam (

+  XENBUS_DEVICE *Dev,

+  INTN Index

+  );

+

+/**

+  Hypercall to do different operation on the memory.

+

+  @param Dev        A XENBUS_DEVICE instance.

+  @param Operation  The operation number, e.g. XENMEM_add_to_physmap.

+  @param Arguments  The arguments associated to the operation.

+

+  @return  Return the return value from the hypercall, 0 in case of success

+           otherwise, an error code.

+**/

+INTN

+XenHypercallMemoryOp (

+  IN     XENBUS_DEVICE *Dev,

+  IN     UINTN Operation,

+  IN OUT VOID *Arguments

+  );

+

+/**

+  Do an operation on the event channels.

+

+  @param Dev        A XENBUS_DEVICE instance.

+  @param Operation  The operation number, e.g. EVTCHNOP_send.

+  @param Arguments  The argument associated to the operation.

+

+  @return  Return the return value from the hypercall, 0 in case of success

+           otherwise, an error code.

+**/

+INTN

+XenHypercallEventChannelOp (

+  IN     XENBUS_DEVICE *Dev,

+  IN     INTN Operation,

+  IN OUT VOID *Arguments

+  );

+

+/**

+  Map the shared_info_t page into memory.

+

+  @param Dev    A XENBUS_DEVICE instance.

+

+  @retval EFI_SUCCESS     Dev->SharedInfo whill contain a pointer to

+                          the shared info page

+  @retval EFI_LOAD_ERROR  The shared info page could not be mapped. The

+                          hypercall returned an error.

+**/

+EFI_STATUS

+XenGetSharedInfoPage (

+  IN OUT XENBUS_DEVICE *Dev

+  );

+

+#endif