[edk2-devel] [PATCH v3 3/8] Ovmf/HardwareInfoLib: Add Dxe lib to dynamically parse heterogenous data
Ojeda Leon, Nicolas via groups.io
ncoleon=amazon.com at groups.io
Tue Jan 25 14:30:10 UTC 2022
Following the Hardware Info library, create the DxeHardwareInfoLib
which implements the whole API capable of parsing heterogeneous hardware
information. The list-like API grants callers a flexible and common
pattern to retrieve the data. Moreover, the initial source is a BLOB
which generalizes the host-to-guest transmission mechanism.
The Hardware Info library main objective is to provide a way to
describe non-discoverable hardware so that the host can share the
available resources with the guest in Ovmf platforms. This change
features and embraces the main idea behind the library by providing
an API that parses a BLOB into a linked list to retrieve hardware
data from any source. Additionally, list-like APIs are provided so
that the hardware info list can be traversed conveniently.
Similarly, the capability is provided to filter results by specific
hardware types. However, heterogeneous elements can be added to the
list, increasing the flexibility. This way, a single source, for
example a fw-cfg file, can be used to describe several instances of
multiple types of hardware.
This part of the Hardware Info library makes use of dynamic memory
and is intended for stages in which memory services are available.
A motivation example is the PciHostBridgeLib. This library, part
of the PCI driver populates the list of PCI root bridges during DXE
stage for future steps to discover the resources under them. The
hardware info library can be used to obtain the detailed description
of available host bridges, for instance in the form of a fw-cfg file,
and parse that information into a dynmaic list that allows, first to
verify consistency of the data, and second discover the resources
availabe for each root bridge.
Cc: Alexander Graf <graf at amazon.de>
Cc: Gerd Hoffmann <kraxel at redhat.com>
Signed-off-by: Nicolas Ojeda Leon <ncoleon at amazon.com>
---
.../HardwareInfoLib/DxeHardwareInfoLib.inf | 43 +++
.../Library/HardwareInfoLib/HardwareInfoDxe.c | 255 ++++++++++++++++++
OvmfPkg/OvmfPkgX64.dsc | 1 +
3 files changed, 299 insertions(+)
create mode 100644 OvmfPkg/Library/HardwareInfoLib/DxeHardwareInfoLib.inf
create mode 100644 OvmfPkg/Library/HardwareInfoLib/HardwareInfoDxe.c
diff --git a/OvmfPkg/Library/HardwareInfoLib/DxeHardwareInfoLib.inf b/OvmfPkg/Library/HardwareInfoLib/DxeHardwareInfoLib.inf
new file mode 100644
index 0000000000..0a93d24b8a
--- /dev/null
+++ b/OvmfPkg/Library/HardwareInfoLib/DxeHardwareInfoLib.inf
@@ -0,0 +1,43 @@
+## @file
+# Hardware information library to describe non-discoverable hardware resources
+#
+# Copyright 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+#
+# 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.
+#
+##
+
+[Defines]
+ INF_VERSION = 0x00010005
+ BASE_NAME = DxeHardwareInfoLib
+ FILE_GUID = F60B206A-5C56-11EC-AEAC-67CB080BCFF2
+ MODULE_TYPE = BASE
+ VERSION_STRING = 1.0
+ LIBRARY_CLASS = DxeHardwareInfoLib
+
+#
+# The following information is for reference only and not required by the build
+# tools.
+#
+# VALID_ARCHITECTURES = X64
+#
+
+[Sources]
+ HardwareInfoDxe.c
+ HardwareInfoPciHostBridgeLib.c
+ QemuFwCfgHardwareInfoLib.c
+
+[Packages]
+ MdeModulePkg/MdeModulePkg.dec
+ MdePkg/MdePkg.dec
+ OvmfPkg/OvmfPkg.dec
+
+[LibraryClasses]
+ BaseMemoryLib
+ DebugLib
+ MemoryAllocationLib
diff --git a/OvmfPkg/Library/HardwareInfoLib/HardwareInfoDxe.c b/OvmfPkg/Library/HardwareInfoLib/HardwareInfoDxe.c
new file mode 100644
index 0000000000..4f0b51c942
--- /dev/null
+++ b/OvmfPkg/Library/HardwareInfoLib/HardwareInfoDxe.c
@@ -0,0 +1,255 @@
+/*/@file
+ Hardware info parsing functions.
+ Binary data is expected as a consecutive series of header - object pairs.
+ Complete library providing list-like interface to dynamically manipulate
+ hardware info objects and parsing from a generic blob.
+
+ Copyright 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+
+ 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 <string.h>
+#include <Uefi/UefiBaseType.h>
+#include <Uefi/UefiSpec.h>
+#include <Library/DebugLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/BaseLib.h>
+#include <Library/UefiLib.h>
+
+#include <Library/HardwareInfoLib.h>
+
+EFI_STATUS
+CreateHardwareInfoList (
+ IN UINT8 *Blob,
+ IN UINTN BlobSize,
+ IN HARDWARE_INFO_TYPE TypeFilter,
+ OUT LIST_ENTRY *ListHead
+ )
+{
+ UINT8 *Index;
+ HARDWARE_INFO *HwComponent;
+
+ if ((Blob == NULL) || (BlobSize <= 0) ||
+ (ListHead == NULL))
+ {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ Index = Blob;
+ while (Index < (Blob + BlobSize)) {
+ HwComponent = AllocateZeroPool (sizeof (HARDWARE_INFO));
+
+ if (HwComponent == NULL) {
+ goto FailedAllocate;
+ }
+
+ HwComponent->Header.Type.Uint64 = *((UINT64 *)Index);
+ Index += sizeof (HwComponent->Header.Type);
+ HwComponent->Header.Size = *((UINT64 *)(Index));
+ Index += sizeof (HwComponent->Header.Size);
+
+ //
+ // Check if optional TypeFilter is set, skip if the current
+ // object is of a different type and release the partially
+ // allocated object
+ //
+ if ((TypeFilter != HardwareInfoTypeUndefined) &&
+ (HwComponent->Header.Type.Value != TypeFilter))
+ {
+ FreePool (HwComponent);
+ Index += HwComponent->Header.Size;
+ continue;
+ }
+
+ HwComponent->Data.Raw = AllocateZeroPool (HwComponent->Header.Size);
+ if (HwComponent->Data.Raw == NULL) {
+ goto FreeResources;
+ }
+
+ CopyMem (HwComponent->Data.Raw, Index, HwComponent->Header.Size);
+ Index += HwComponent->Header.Size;
+
+ InsertTailList (ListHead, &HwComponent->Link);
+ }
+
+ return EFI_SUCCESS;
+
+FreeResources:
+ //
+ // Clean the resources allocated in the incomplete cycle
+ //
+ FreePool (HwComponent);
+
+FailedAllocate:
+ DEBUG ((
+ EFI_D_ERROR,
+ "%a: Failed to allocate memory for hardware info\n",
+ __FUNCTION__
+ ));
+
+ return EFI_OUT_OF_RESOURCES;
+}
+
+VOID
+FreeHardwareInfoList (
+ IN OUT LIST_ENTRY *ListHead
+ )
+{
+ LIST_ENTRY *CurrentLink;
+ HARDWARE_INFO *HwComponent;
+
+ if (IsListEmpty (ListHead)) {
+ return;
+ }
+
+ CurrentLink = ListHead->ForwardLink;
+ while (CurrentLink != NULL && CurrentLink != ListHead) {
+ HwComponent = HARDWARE_INFO_FROM_LINK (CurrentLink);
+
+ //
+ // Remove item from list before invalidating the pointers
+ //
+ CurrentLink = RemoveEntryList (CurrentLink);
+
+ FreePool (HwComponent->Data.Raw);
+ FreePool (HwComponent);
+ }
+}
+
+/**
+ Validates if the specified Node has a valid data size and is of
+ specified type.
+ The data size can be less or equal to the provided type size to be
+ regarded as valid and thus accessible with the typed pointer.
+
+ For future compatibility the size is allowed to be smaller so that
+ different versions interpret fields differently and, particularly,
+ have smaller data structures. However, it cannot be larger than the
+ type size to avoid accessing memory out of bounds.
+
+ @param[in] Node Hardware Info node to be validated
+ @param[in] TypeSize Size (in bytes) of the data type intended to be
+ used to dereference the data.
+ @retval TRUE Node is valid and can be accessed
+ @retval FALSE Node is not valid
+/*/
+STATIC
+BOOLEAN
+IsHardwareInfoNodeValidByType (
+ IN LIST_ENTRY *ListHead,
+ IN LIST_ENTRY *Link,
+ IN HARDWARE_INFO_TYPE Type,
+ IN UINTN TypeSize
+ )
+{
+ HARDWARE_INFO *HwComponent;
+
+ if (IsNull (ListHead, Link)) {
+ return FALSE;
+ }
+
+ HwComponent = HARDWARE_INFO_FROM_LINK (Link);
+
+ //
+ // Verify if the node type is the specified one and the size of
+ // the data allocated to the node is greater than the size of
+ // the type intended to dereference it in order to avoid access
+ // to memory out of bondaries.
+ //
+ if ((HwComponent->Header.Type.Value == Type) &&
+ (HwComponent->Header.Size >= TypeSize))
+ {
+ return TRUE;
+ }
+
+ return FALSE;
+}
+
+UINTN
+GetHardwareInfoCountByType (
+ IN LIST_ENTRY *ListHead,
+ IN HARDWARE_INFO_TYPE Type,
+ IN UINTN TypeSize
+ )
+{
+ UINTN Count;
+ LIST_ENTRY *Link;
+
+ Count = 0;
+ for (Link = GetFirstHardwareInfoByType (ListHead, Type, TypeSize);
+ !IsNull (ListHead, Link);
+ Link = GetNextHardwareInfoByType (ListHead, Link, Type, TypeSize))
+ {
+ if (IsHardwareInfoNodeValidByType (ListHead, Link, Type, TypeSize)) {
+ Count++;
+ }
+ }
+
+ return Count;
+}
+
+LIST_ENTRY *
+GetFirstHardwareInfoByType (
+ IN LIST_ENTRY *ListHead,
+ IN HARDWARE_INFO_TYPE Type,
+ IN UINTN TypeSize
+ )
+{
+ LIST_ENTRY *Link;
+
+ if (IsListEmpty (ListHead)) {
+ return ListHead;
+ }
+
+ Link = GetFirstNode (ListHead);
+
+ if (IsHardwareInfoNodeValidByType (ListHead, Link, Type, TypeSize)) {
+ return Link;
+ }
+
+ return GetNextHardwareInfoByType (ListHead, Link, Type, TypeSize);
+}
+
+LIST_ENTRY *
+GetNextHardwareInfoByType (
+ IN LIST_ENTRY *ListHead,
+ IN LIST_ENTRY *Node,
+ IN HARDWARE_INFO_TYPE Type,
+ IN UINTN TypeSize
+ )
+{
+ LIST_ENTRY *Link;
+
+ Link = GetNextNode (ListHead, Node);
+
+ while (!IsNull (ListHead, Link)) {
+ if (IsHardwareInfoNodeValidByType (ListHead, Link, Type, TypeSize)) {
+ //
+ // Found a node of specified type and with valid size. Break and
+ // return the found node.
+ //
+ break;
+ }
+
+ Link = GetNextNode (ListHead, Link);
+ }
+
+ return Link;
+}
+
+BOOLEAN
+EndOfHardwareInfoList (
+ IN LIST_ENTRY *ListHead,
+ IN LIST_ENTRY *Node
+ )
+{
+ return IsNull (ListHead, Node);
+}
diff --git a/OvmfPkg/OvmfPkgX64.dsc b/OvmfPkg/OvmfPkgX64.dsc
index 7a36f62e9f..b376387b7c 100644
--- a/OvmfPkg/OvmfPkgX64.dsc
+++ b/OvmfPkg/OvmfPkgX64.dsc
@@ -181,6 +181,7 @@
LoadLinuxLib|OvmfPkg/Library/LoadLinuxLib/LoadLinuxLib.inf
MemEncryptSevLib|OvmfPkg/Library/BaseMemEncryptSevLib/DxeMemEncryptSevLib.inf
PeiHardwareInfoLib|OvmfPkg/Library/HardwareInfoLib/PeiHardwareInfoLib.inf
+ DxeHardwareInfoLib|OvmfPkg/Library/HardwareInfoLib/DxeHardwareInfoLib.inf
!if $(SMM_REQUIRE) == FALSE
LockBoxLib|OvmfPkg/Library/LockBoxLib/LockBoxBaseLib.inf
!endif
--
2.17.1
Amazon Development Center Germany GmbH
Krausenstr. 38
10117 Berlin
Geschaeftsfuehrung: Christian Schlaeger, Jonathan Weiss
Eingetragen am Amtsgericht Charlottenburg unter HRB 149173 B
Sitz: Berlin
Ust-ID: DE 289 237 879
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