add bluescreen demo

c_os/kernel/Paging.cc

@@ -67,12 +67,6 @@
 #define FST_ALLOCABLE_PAGE 0x202000
 #define LST_ALLOCABLE_PAGE 0x2FF000
 
-// Externe Funktionen in startup.asm
-extern "C" {
-    void paging_on(unsigned int* p_pdir);          // Paging einschalten
-    void invalidate_tlb_entry(unsigned int* ptr);  // Page in TLB invalid.
-}
-
 /*****************************************************************************
  * Funktion:        pg_alloc_page                                            *
  *---------------------------------------------------------------------------*

c_os/kernel/Paging.h

@@ -52,6 +52,12 @@
 #ifndef __Paging_include__
 #define __Paging_include__
 
+// Externe Funktionen in startup.asm
+extern "C" {
+    void paging_on(unsigned int* p_pdir);          // Paging einschalten
+    void invalidate_tlb_entry(unsigned int* ptr);  // Page in TLB invalid.
+}
+
 // ativiert paging
 extern void pg_init();
 

c_os/main.cc

@@ -11,12 +11,11 @@
  *****************************************************************************/
 
 #include "kernel/Globals.h"
-
-// TODO: paging/bluescreen demo, don't include here
 #include "kernel/Paging.h"
 
 // Demos
 // TODO: Make demo header or include through demo menu
+#include "user/demo/BlueScreenDemo.h"
 #include "user/demo/HeapDemo.h"
 #include "user/demo/KeyboardDemo.h"
 #include "user/demo/PCSPKdemo.h"
@@ -63,28 +62,13 @@ int main() {
     // This has to happen after the allocator is initialized but before the scheduler is started
     pg_init();
 
-    // TODO: Move this to demo
-    // Trigger Bluescreen
-    // kout << "Trigger Bluescreen, if you can read this it didn't work" << endl;
-
-    // BlueScreen 1
-    // asm("int $3");
-
-    // BlueScreen 2
-    // unsigned int* page = pg_alloc_page();
-    // *page = 42;
-    // pg_write_protect_page(page);
-    // invalidate_tlb_entry(page); // If we don't invalidate after first access the write protection
-    //                             // won't work as no lookup is performed (address in tlb)
-    // *page = 42; // We map logical to physical 1:1 so no need to do any lookup
-    //             // If tlb is invalidated this access produces a pagefault
-
     // Demos
     // scheduler.ready(new TextDemo());
     // scheduler.ready(new PCSPKdemo(&PCSPK::aerodynamic));
     // scheduler.ready(new KeyboardDemo());
     // scheduler.ready(new HeapDemo());
     // scheduler.ready(new VBEdemo());
+    // scheduler.ready(new BlueScreenDemo());
     // scheduler.ready(new PreemptiveThreadDemo());
 
     // Scheduler starten (schedule() erzeugt den Idle-Thread)

c_os/user/demo/BlueScreenDemo.cc

@@ -0,0 +1,20 @@
+#include "user/demo/BlueScreenDemo.h"
+#include "kernel/Paging.h"
+
+void BlueScreenDemo::run() {
+    kout << "Trigger Bluescreen, if you can read this it didn't work" << endl;
+
+    // BlueScreen 1
+    // asm("int $3");
+
+    // BlueScreen 2
+    unsigned int* page = pg_alloc_page();
+    *page = 42;
+    pg_write_protect_page(page);
+    invalidate_tlb_entry(page); // If we don't invalidate after first access the write protection
+                                // won't work as no lookup is performed (address in tlb)
+    *page = 42; // We map logical to physical 1:1 so no need to do any lookup
+                // If tlb is invalidated this access produces a pagefault
+
+    scheduler.exit();
+}

c_os/user/demo/BlueScreenDemo.h

@@ -0,0 +1,20 @@
+#ifndef __BlueScreenDemo_include__
+#define __BlueScreenDemo_include__
+
+#include "kernel/Globals.h"
+#include "kernel/threads/Thread.h"
+
+class BlueScreenDemo : public Thread {
+private:
+    BlueScreenDemo(const BlueScreenDemo& copy) = delete;
+
+public:
+    BlueScreenDemo() {
+        kout << "Initialized BlueScreenDemo" << endl;
+    }
+
+    void run() override;
+};
+
+
+#endif