Merge remote-tracking branch 'Kernel/master'

Kernel/core/memory/kstack.cpp

@@ -0,0 +1,75 @@
+/*
+	This file is part of Fennix Kernel.
+
+	Fennix Kernel is free software: you can redistribute it and/or
+	modify it under the terms of the GNU General Public License as
+	published by the Free Software Foundation, either version 3 of
+	the License, or (at your option) any later version.
+
+	Fennix Kernel is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with Fennix Kernel. If not, see <https://www.gnu.org/licenses/>.
+*/
+
+#include <memory.hpp>
+
+#include "../../kernel.h"
+
+namespace Memory
+{
+	KernelStackManager::StackAllocation KernelStackManager::DetailedAllocate(size_t Size)
+	{
+		SmartLock(StackLock);
+		Size += 0x10;
+
+		size_t pagesNeeded = TO_PAGES(Size);
+		size_t stackSize = pagesNeeded * PAGE_SIZE;
+
+		assert((CurrentStackTop - stackSize) > KERNEL_STACK_BASE);
+
+		void *physicalMemory = KernelAllocator.RequestPages(pagesNeeded);
+		void *virtualAddress = (void *)(CurrentStackTop - stackSize);
+
+		Memory::Virtual vmm(KernelPageTable);
+		vmm.Map(virtualAddress, physicalMemory, stackSize, Memory::RW | Memory::G);
+
+		AllocatedStacks.push_back({physicalMemory, virtualAddress, stackSize});
+		CurrentStackTop -= stackSize;
+		TotalSize += stackSize;
+		return {physicalMemory, virtualAddress, stackSize};
+	}
+
+	void *KernelStackManager::Allocate(size_t Size)
+	{
+		return this->DetailedAllocate(Size).VirtualAddress;
+	}
+
+	void KernelStackManager::Free(void *Address)
+	{
+		SmartLock(StackLock);
+
+		auto it = std::find_if(AllocatedStacks.begin(), AllocatedStacks.end(),
+							   [Address](const StackAllocation &stack)
+							   {
+								   return stack.VirtualAddress == Address;
+							   });
+
+		if (it == AllocatedStacks.end())
+			return;
+
+		size_t pagesToFree = TO_PAGES(it->Size);
+		Memory::Virtual vmm(KernelPageTable);
+		vmm.Unmap(Address, it->Size);
+		KernelAllocator.FreePages(it->PhysicalAddress, pagesToFree);
+
+		TotalSize -= it->Size;
+		AllocatedStacks.erase(it);
+	}
+
+	KernelStackManager::KernelStackManager() {}
+	KernelStackManager::~KernelStackManager() {}
+}