From 1a23e82f91690482c416928f2276be326c8116d3 Mon Sep 17 00:00:00 2001
From: momo5502 <mauriceheumann@gmail.com>
Date: Mon, 18 Nov 2024 17:15:38 +0100
Subject: [PATCH] Integrate MMIO into the memory manager

---
 src/emulator/memory_manager.cpp | 27 ++++++++++++++++++++++++++-
 src/emulator/memory_manager.hpp |  3 ++-
 2 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/src/emulator/memory_manager.cpp b/src/emulator/memory_manager.cpp
index 4086899e..0dee8de5 100644
--- a/src/emulator/memory_manager.cpp
+++ b/src/emulator/memory_manager.cpp
@@ -198,6 +198,24 @@ bool memory_manager::protect_memory(const uint64_t address, const size_t size, c
 	return true;
 }
 
+bool memory_manager::allocate_mmio(uint64_t address, size_t size, mmio_read_callback read_cb,
+                                   mmio_write_callback write_cb)
+{
+	if (this->overlaps_reserved_region(address, size))
+	{
+		return false;
+	}
+
+	this->map_mmio(address, size, std::move(read_cb), std::move(write_cb));
+
+	const auto entry = this->reserved_regions_.try_emplace(address, size).first;
+	entry->second.committed_regions[address] = committed_region{
+		.length = size, .pemissions = memory_permission::read_write, .is_mmio = true,
+	};
+
+	return true;
+}
+
 bool memory_manager::allocate_memory(const uint64_t address, const size_t size, const memory_permission permissions,
                                      const bool reserve_only)
 {
@@ -211,7 +229,9 @@ bool memory_manager::allocate_memory(const uint64_t address, const size_t size,
 	if (!reserve_only)
 	{
 		this->map_memory(address, size, permissions);
-		entry->second.committed_regions[address] = committed_region{size, permissions};
+		entry->second.committed_regions[address] = committed_region{
+			.length = size, .pemissions = memory_permission::read_write
+		};
 	}
 
 	return true;
@@ -303,6 +323,11 @@ bool memory_manager::decommit_memory(const uint64_t address, const size_t size)
 			break;
 		}
 
+		if (i->second.is_mmio)
+		{
+			throw std::runtime_error("Not allowed to decommit MMIO!");
+		}
+
 		const auto sub_region_end = i->first + i->second.length;
 		if (i->first >= address && sub_region_end <= end)
 		{
diff --git a/src/emulator/memory_manager.hpp b/src/emulator/memory_manager.hpp
index c59ff3ce..b88d1cef 100644
--- a/src/emulator/memory_manager.hpp
+++ b/src/emulator/memory_manager.hpp
@@ -23,6 +23,7 @@ public:
 	{
 		size_t length{};
 		memory_permission pemissions{};
+		bool is_mmio{false};
 	};
 
 	using committed_region_map = std::map<uint64_t, committed_region>;
@@ -82,6 +83,7 @@ public:
 	bool protect_memory(uint64_t address, size_t size, memory_permission permissions,
 	                    memory_permission* old_permissions = nullptr);
 
+	bool allocate_mmio(uint64_t address, size_t size, mmio_read_callback read_cb, mmio_write_callback write_cb);
 	bool allocate_memory(uint64_t address, size_t size, memory_permission permissions,
 	                     bool reserve_only = false);
 
@@ -118,7 +120,6 @@ private:
 
 	virtual void apply_memory_protection(uint64_t address, size_t size, memory_permission permissions) = 0;
 
-
 protected:
 	void serialize_memory_state(utils::buffer_serializer& buffer, bool is_snapshot) const;
 	void deserialize_memory_state(utils::buffer_deserializer& buffer, bool is_snapshot);