From 5d6bf24a9df7c5c486c3a1c8a2f5a6d22b8a01fd Mon Sep 17 00:00:00 2001
From: wheremyfoodat <gponiris2004@gmail.com>
Date: Tue, 21 Mar 2023 02:32:47 +0200
Subject: [PATCH] [Kernel] Add memory mirroring function & throw warning on
 mprotect

---
 include/memory.hpp                    |  4 ++++
 src/core/PICA/gpu.cpp                 |  5 +++++
 src/core/kernel/memory_management.cpp |  8 ++++++++
 src/core/memory.cpp                   | 18 ++++++++++++++++++
 4 files changed, 35 insertions(+)

diff --git a/include/memory.hpp b/include/memory.hpp
index ddc2da35..c10e0649 100644
--- a/include/memory.hpp
+++ b/include/memory.hpp
@@ -223,6 +223,10 @@ public:
 	// Returns a pointer to the FCRAM block used for the memory if allocation succeeded
 	u8* mapSharedMemory(Handle handle, u32 vaddr, u32 myPerms, u32 otherPerms);
 
+	// Mirrors the page mapping for "size" bytes starting from sourceAddress, to "size" bytes in destAddress
+	// All of the above must be page-aligned.
+	void mirrorMapping(u32 destAddress, u32 sourceAddress, u32 size);
+
 	// Backup of the game's CXI partition info, if any
 	std::optional<NCCH> loadedCXI = std::nullopt;
 	// File handle for reading the loaded ncch
diff --git a/src/core/PICA/gpu.cpp b/src/core/PICA/gpu.cpp
index 9266c28c..5b817888 100644
--- a/src/core/PICA/gpu.cpp
+++ b/src/core/PICA/gpu.cpp
@@ -196,6 +196,7 @@ void GPU::drawArrays() {
 
 		//printf("(x, y, z, w) = (%f, %f, %f, %f)\n", (double)vertices[i].position.x(), (double)vertices[i].position.y(), (double)vertices[i].position.z(), (double)vertices[i].position.w());
 		//printf("(r, g, b, a) = (%f, %f, %f, %f)\n", (double)vertices[i].colour.r(), (double)vertices[i].colour.g(), (double)vertices[i].colour.b(), (double)vertices[i].colour.a());
+		//printf("(u, v      ) = (%f, %f)\n", vertices[i].UVs.u(), vertices[i].UVs.v());
 	}
 
 	// The fourth type is meant to be "Geometry primitive". TODO: Find out what that is
@@ -221,6 +222,10 @@ Vertex GPU::getImmediateModeVertex() {
 	std::memcpy(&v.colour, &shaderUnit.vs.outputs[1], sizeof(vec4f));
 	std::memcpy(&v.UVs, &shaderUnit.vs.outputs[2], 2 * sizeof(f24));
 
+	printf("(x, y, z, w) = (%f, %f, %f, %f)\n", (double)v.position.x(), (double)v.position.y(), (double)v.position.z(), (double)v.position.w());
+	printf("(r, g, b, a) = (%f, %f, %f, %f)\n", (double)v.colour.r(), (double)v.colour.g(), (double)v.colour.b(), (double)v.colour.a());
+	printf("(u, v      ) = (%f, %f)\n", v.UVs.u(), v.UVs.v());
+
 	return v;
 }
 void GPU::fireDMA(u32 dest, u32 source, u32 size) {
diff --git a/src/core/kernel/memory_management.cpp b/src/core/kernel/memory_management.cpp
index 3c171231..18aa93a6 100644
--- a/src/core/kernel/memory_management.cpp
+++ b/src/core/kernel/memory_management.cpp
@@ -79,6 +79,14 @@ void Kernel::controlMemory() {
 			break;
 		}
 
+		case Operation::Map:
+			mem.mirrorMapping(addr0, addr1, size);
+			break;
+
+		case Operation::Protect:
+			Helpers::warn("Ignoring mprotect! Hope nothing goes wrong but if the game accesses invalid memory or crashes then we prolly need to implement this\n");
+			break;
+
 		default: Helpers::panic("ControlMemory: unknown operation %X\n", operation);
 	}
 
diff --git a/src/core/memory.cpp b/src/core/memory.cpp
index e89344e7..65e3f9e2 100644
--- a/src/core/memory.cpp
+++ b/src/core/memory.cpp
@@ -392,6 +392,24 @@ u8* Memory::mapSharedMemory(Handle handle, u32 vaddr, u32 myPerms, u32 otherPerm
 	return nullptr;
 }
 
+void Memory::mirrorMapping(u32 destAddress, u32 sourceAddress, u32 size) {
+	// Should theoretically be unreachable, only here for safety purposes
+	assert(isAligned(destAddress) && isAligned(sourceAddress) && isAligned(size));
+
+	const u32 pageCount = size / pageSize; // How many pages we need to mirror
+	for (u32 i = 0; i < pageCount; i++) {
+		// Redo the shift here to "properly" handle wrapping around the address space instead of reading OoB
+		const u32 sourcePage = sourceAddress / pageSize;
+		const u32 destPage = destAddress / pageSize;
+
+		readTable[destPage] = readTable[sourcePage];
+		writeTable[destPage] = writeTable[sourcePage];
+
+		sourceAddress += pageSize;
+		destAddress += pageSize;
+	}
+}
+
 // Get the number of ms since Jan 1 1900
 u64 Memory::timeSince3DSEpoch() {
 	using namespace std::chrono;