Kernel: Really big improvements on Paged Memory Model.

Bootloader: Design shift in BFileReader class.

Signed-off-by: Amlal El Mahrouss <amlalelmahrouss@icloud.com>

3 files changed, 46 insertions, 13 deletions

diff --git a/Private/Source/KernelHeap.cxx b/Private/Source/KernelHeap.cxx
index 42ea0187..603b91b3 100644
--- a/Private/Source/KernelHeap.cxx
+++ b/Private/Source/KernelHeap.cxx
@@ -9,6 +9,8 @@
 
 #include <NewKit/KernelHeap.hpp>
 
+#include "NewKit/PageManager.hpp"
+
 //! @file KernelHeap.cpp
 //! @brief Kernel allocator.
 
@@ -48,6 +50,8 @@ VoidPtr ke_new_ke_heap(const SizeT &sz, const bool rw, const bool user) {
   Ref<PTEWrapper *> wrapper = kPmm.RequestPage(user, rw);
 
   if (wrapper) {
+    wrapper->NoExecute(true);
+
     kLastWrapper = wrapper;
 
     kWrapperList[kWrapperCount] = wrapper;
@@ -67,15 +71,27 @@ Int32 ke_delete_ke_heap(voidPtr ptr) {
     const UIntPtr virtualAddress = reinterpret_cast<UIntPtr>(ptr);
 
     if (kLastWrapper && virtualAddress == kLastWrapper->VirtualAddress()) {
-      return kPmm.FreePage(kLastWrapper);
+      if (kPmm.FreePage(kLastWrapper)) {
+        kLastWrapper->NoExecute(false);
+        return true;
+      }
+
+      return false;
     }
 
-    Ref<PTEWrapper *> wrapper;
+    Ref<PTEWrapper *> wrapper{nullptr};
 
     for (SizeT indexWrapper = 0; indexWrapper < kWrapperCount; ++indexWrapper) {
       if (kWrapperList[indexWrapper]->VirtualAddress() == virtualAddress) {
         wrapper = kWrapperList[indexWrapper];
-        return kPmm.FreePage(wrapper);
+
+        // if page is no more, then mark it also as non executable.
+        if (kPmm.FreePage(wrapper)) {
+          wrapper->NoExecute(false);
+          return true;
+        }
+
+        return false;
       }
     }
   }
@@ -108,11 +124,10 @@ Boolean kernel_valid_ptr(voidPtr ptr) {
 }
 
 /// @brief The Kernel heap initializer function.
-/// @return 
-Void ke_init_ke_heap() noexcept
-{
+/// @return
+Void ke_init_ke_heap() noexcept {
   kWrapperCount = 0UL;
-  Ref<PTEWrapper *> kLastWrapper = Ref<PTEWrapper*>(nullptr);
+  Ref<PTEWrapper *> kLastWrapper = Ref<PTEWrapper *>(nullptr);
   Pmm kPmm = Pmm();
 }
 }  // namespace HCore
diff --git a/Private/Source/PageManager.cxx b/Private/Source/PageManager.cxx
index 95097f99..d6455a18 100644
--- a/Private/Source/PageManager.cxx
+++ b/Private/Source/PageManager.cxx
@@ -85,8 +85,20 @@ bool PageManager::Free(Ref<PTEWrapper *> &wrapper) {
   return false;
 }
 
+////////////////////////////
+
+// VIRTUAL ADDRESS
+
+////////////////////////////
+
 const UIntPtr &PTEWrapper::VirtualAddress() { return m_VirtAddr; }
 
+////////////////////////////
+
+// PAGE GETTERS
+
+////////////////////////////
+
 bool PTEWrapper::Shareable() {
   auto raw = reinterpret_cast<PTE *>(m_VirtAddr);
 
@@ -120,4 +132,13 @@ bool PTEWrapper::Access() {
 
   return m_Accessed;
 }
+
+////////////////////////////
+
+// NO EXECUTE PROTECTION
+
+////////////////////////////
+
+void PTEWrapper::NoExecute(const bool enable) { this->m_ExecDisable = enable; }
+const bool &PTEWrapper::NoExecute() { return this->m_ExecDisable; }
 }  // namespace HCore
diff --git a/Private/Source/Pmm.cxx b/Private/Source/Pmm.cxx
index aa5a3c89..76191fdd 100644
--- a/Private/Source/Pmm.cxx
+++ b/Private/Source/Pmm.cxx
@@ -11,11 +11,8 @@
 #include <NewKit/Pmm.hpp>
 
 namespace HCore {
-Pmm::Pmm() = default;
-
-Pmm::Pmm(Ref<PageManager *> &pm) : m_PageManager(pm) {
-  MUST_PASS(pm.Leak());
-  kcout << "[PMM] New PhysicalMemoryManager\r\n";
+Pmm::Pmm() : m_PageManager() {
+  kcout << "[PMM] Allocate PageMemoryManager\r\n";
 }
 
 Pmm::~Pmm() = default;
@@ -23,7 +20,7 @@ Pmm::~Pmm() = default;
 /* If this returns Null pointer, enter emergency mode */
 Ref<PTEWrapper *> Pmm::RequestPage(Boolean user, Boolean readWrite) {
   if (m_PageManager) {
-    PTEWrapper *pt = m_PageManager.Leak()->Request(user, readWrite, true);
+    PTEWrapper *pt = m_PageManager.Leak().Request(user, readWrite, true);
 
     if (pt) return Ref<PTEWrapper *>(pt);