From e0778d0a121706e0363fb859964502544f331725 Mon Sep 17 00:00:00 2001
From: belliash <belliash@codingworkshop.eu.org>
Date: Thu, 16 Mar 2023 23:40:38 +0100
Subject: [PATCH] Introduce kernel executive

---
 sdk/xtdk/extypes.h    | 26 ++++++++++++++++++++++++++
 sdk/xtdk/xtkmapi.h    |  1 +
 sdk/xtdk/xtstruct.h   |  1 +
 xtoskrnl/ex/rundown.c | 28 ++++++++++++++++++++++++++++
 4 files changed, 56 insertions(+)
 create mode 100644 sdk/xtdk/extypes.h
 create mode 100644 xtoskrnl/ex/rundown.c

diff --git a/sdk/xtdk/extypes.h b/sdk/xtdk/extypes.h
new file mode 100644
index 0000000..371c6d1
--- /dev/null
+++ b/sdk/xtdk/extypes.h
@@ -0,0 +1,26 @@
+/**
+ * PROJECT:         ExectOS
+ * COPYRIGHT:       See COPYING.md in the top level directory
+ * FILE:            sdk/xtdk/extypes.h
+ * DESCRIPTION:     Kernel executive structures definitions
+ * DEVELOPERS:      Rafal Kupiec <belliash@codingworkshop.eu.org>
+ */
+
+#ifndef __XTDK_EXTYPES_H
+#define __XTDK_EXTYPES_H
+
+#include <xtbase.h>
+#include <xttypes.h>
+
+
+/* Executive rundown protection structure definition */
+typedef struct _EX_RUNDOWN_REFERENCE
+{
+    union
+    {
+        ULONG_PTR Count;
+        PVOID Ptr;
+    };
+} EX_RUNDOWN_REFERENCE, *PEX_RUNDOWN_REFERENCE;
+
+#endif /* __XTDK_EXTYPES_H */
diff --git a/sdk/xtdk/xtkmapi.h b/sdk/xtdk/xtkmapi.h
index ae09189..db672dc 100644
--- a/sdk/xtdk/xtkmapi.h
+++ b/sdk/xtdk/xtkmapi.h
@@ -26,6 +26,7 @@
 #include <xtuefi.h>
 
 /* Low level data types headers */
+#include <extypes.h>
 #include <hltypes.h>
 #include <iotypes.h>
 #include <ketypes.h>
diff --git a/sdk/xtdk/xtstruct.h b/sdk/xtdk/xtstruct.h
index b6c9022..2e3753d 100644
--- a/sdk/xtdk/xtstruct.h
+++ b/sdk/xtdk/xtstruct.h
@@ -193,6 +193,7 @@ typedef struct _EFI_VENDOR_DEVICE_PATH EFI_VENDOR_DEVICE_PATH, *PEFI_VENDOR_DEVI
 typedef struct _EFI_VLAN_DEVICE_PATH EFI_VLAN_DEVICE_PATH, *PEFI_VLAN_DEVICE_PATH;
 typedef struct _EPROCESS EPROCESS, *PEPROCESS;
 typedef struct _ETHREAD ETHREAD, *PETHREAD;
+typedef struct _EX_RUNDOWN_REFERENCE EX_RUNDOWN_REFERENCE, *PEX_RUNDOWN_REFERENCE;
 typedef struct _EXCEPTION_RECORD EXCEPTION_RECORD, *PEXCEPTION_RECORD;
 typedef struct _EXCEPTION_REGISTRATION_RECORD EXCEPTION_REGISTRATION_RECORD, *PEXCEPTION_REGISTRATION_RECORD;
 typedef struct _FIRMWARE_INFORMATION_BLOCK FIRMWARE_INFORMATION_BLOCK, *PFIRMWARE_INFORMATION_BLOCK;
diff --git a/xtoskrnl/ex/rundown.c b/xtoskrnl/ex/rundown.c
new file mode 100644
index 0000000..193398e
--- /dev/null
+++ b/xtoskrnl/ex/rundown.c
@@ -0,0 +1,28 @@
+/**
+ * PROJECT:         ExectOS
+ * COPYRIGHT:       See COPYING.md in the top level directory
+ * FILE:            xtoskrnl/ex/rundown.c
+ * DESCRIPTION:     Rundown protection mechanism
+ * DEVELOPERS:      Rafal Kupiec <belliash@codingworkshop.eu.org>
+ */
+
+#include <xtos.h>
+
+
+/**
+ * Initializes the rundown protection descriptor.
+ *
+ * @param Descriptor
+ *        Supplies a pointer to the descriptor to be initialized.
+ *
+ * @return This routine does not return any value.
+ *
+ * @since NT 5.1
+ */
+XTFASTCALL
+VOID
+ExInitializeRundownProtection(IN PEX_RUNDOWN_REFERENCE Descriptor)
+{
+    /* Reset descriptor counter */
+    Descriptor->Count = 0;
+}