From 7727888087461c71e06202ead8ad856ba42ca434 Mon Sep 17 00:00:00 2001
From: Rafal Kupiec <belliash@codingworkshop.eu.org>
Date: Sun, 4 Feb 2024 23:43:38 +0100
Subject: [PATCH] Implement ArFlushTlb() routine

---
 xtoskrnl/ar/amd64/cpufunc.c   | 15 +++++++++++++++
 xtoskrnl/ar/i686/cpufunc.c    | 15 +++++++++++++++
 xtoskrnl/includes/amd64/ari.h |  4 ++++
 xtoskrnl/includes/i686/ari.h  |  4 ++++
 4 files changed, 38 insertions(+)

diff --git a/xtoskrnl/ar/amd64/cpufunc.c b/xtoskrnl/ar/amd64/cpufunc.c
index d1b21d54..874c8530 100644
--- a/xtoskrnl/ar/amd64/cpufunc.c
+++ b/xtoskrnl/ar/amd64/cpufunc.c
@@ -67,6 +67,21 @@ ArCpuId(IN OUT PCPUID_REGISTERS Registers)
     return TRUE;
 }
 
+/**
+ * Partially flushes the Translation Lookaside Buffer (TLB)
+ *
+ * @return This routine does not return any value.
+ *
+ * @since XT 1.0
+ */
+XTCDECL
+VOID
+ArFlushTlb()
+{
+    /* Flush the TLB by resetting the CR3 */
+    ArWriteControlRegister(3, ArReadControlRegister(3));
+}
+
 /**
  * Gets the address of the current stack register.
  *
diff --git a/xtoskrnl/ar/i686/cpufunc.c b/xtoskrnl/ar/i686/cpufunc.c
index a3ae24f6..27a828de 100644
--- a/xtoskrnl/ar/i686/cpufunc.c
+++ b/xtoskrnl/ar/i686/cpufunc.c
@@ -67,6 +67,21 @@ ArCpuId(IN OUT PCPUID_REGISTERS Registers)
     return TRUE;
 }
 
+/**
+ * Partially flushes the Translation Lookaside Buffer (TLB)
+ *
+ * @return This routine does not return any value.
+ *
+ * @since XT 1.0
+ */
+XTCDECL
+VOID
+ArFlushTlb()
+{
+    /* Flush the TLB by resetting the CR3 */
+    ArWriteControlRegister(3, ArReadControlRegister(3));
+}
+
 /**
  * Gets the address of the current stack register.
  *
diff --git a/xtoskrnl/includes/amd64/ari.h b/xtoskrnl/includes/amd64/ari.h
index 9d1849e7..97dd0455 100644
--- a/xtoskrnl/includes/amd64/ari.h
+++ b/xtoskrnl/includes/amd64/ari.h
@@ -21,6 +21,10 @@ XTCDECL
 BOOLEAN
 ArCpuId(IN OUT PCPUID_REGISTERS Registers);
 
+XTCDECL
+VOID
+ArFlushTlb();
+
 XTASSEMBLY
 XTCDECL
 ULONG_PTR
diff --git a/xtoskrnl/includes/i686/ari.h b/xtoskrnl/includes/i686/ari.h
index 69b8a495..6fd3e5b3 100644
--- a/xtoskrnl/includes/i686/ari.h
+++ b/xtoskrnl/includes/i686/ari.h
@@ -21,6 +21,10 @@ XTCDECL
 BOOLEAN
 ArCpuId(IN OUT PCPUID_REGISTERS Registers);
 
+XTCDECL
+VOID
+ArFlushTlb();
+
 XTASSEMBLY
 XTCDECL
 ULONG_PTR