Memory Cards: mmap on Linux and MacOS

common/Darwin/DarwinMisc.cpp

@@ -291,6 +291,24 @@ void* HostSys::CreateSharedMemory(const char* name, size_t size)
 	return reinterpret_cast<void*>(static_cast<uintptr_t>(port));
 }
 
+void* HostSys::CreateMappingFromFile(FILE* file)
+{
+	return reinterpret_cast<void*>(static_cast<uintptr_t>(fileno(file)));
+}
+
+void* HostSys::MapMapping(void* handle, const PageProtectionMode& mode)
+{
+	const u32 mmap_prot = (mode.CanWrite() ? (PROT_READ | PROT_WRITE) : (PROT_READ)) | (mode.CanExecute() ? PROT_EXEC : 0);
+
+	return mmap(nullptr, 0, mmap_prot, MAP_PRIVATE | MAP_ANON, static_cast<int>(reinterpret_cast<intptr_t>(handle)), 0);
+}
+
+void HostSys::DestroyMapping(void* handle)
+{
+	// The handle mmap requires is the same as the file descriptor.
+	return;
+}
+
 void HostSys::DestroySharedMemory(void* ptr)
 {
 	mach_port_deallocate(mach_task_self(), static_cast<mach_port_t>(reinterpret_cast<uintptr_t>(ptr)));

common/HostSys.h

@@ -101,6 +101,11 @@ namespace HostSys
 
 	extern std::string GetFileMappingName(const char* prefix);
 	extern void* CreateSharedMemory(const char* name, size_t size);
+
+	extern void* CreateMappingFromFile(FILE* file);
+	extern void* MapMapping(void* handle, const PageProtectionMode& mode);
+	extern void DestroyMapping(void* handle);
+
 	extern void DestroySharedMemory(void* ptr);
 	extern void* MapSharedMemory(void* handle, size_t offset, void* baseaddr, size_t size, const PageProtectionMode& mode);
 	extern void UnmapSharedMemory(void* baseaddr, size_t size);

common/Linux/LnxHostSys.cpp

@@ -115,6 +115,22 @@ void* HostSys::CreateSharedMemory(const char* name, size_t size)
 	return reinterpret_cast<void*>(static_cast<intptr_t>(fd));
 }
 
+void* HostSys::CreateMappingFromFile(FILE* file)
+{
+	return reinterpret_cast<void*>(static_cast<intptr_t>(fileno(file)));
+}
+
+void* HostSys::MapMapping(void* handle, const PageProtectionMode& mode)
+{
+	return HostSys::MapSharedMemory(handle, 0, nullptr, 0, mode);
+}
+
+void HostSys::DestroyMapping(void* handle)
+{
+	// The handle mmap requires is the same as the file descriptor.
+	return;
+}
+
 void HostSys::DestroySharedMemory(void* ptr)
 {
 	close(static_cast<int>(reinterpret_cast<intptr_t>(ptr)));

common/Windows/WinHostSys.cpp

@@ -13,6 +13,7 @@
 #include "fmt/core.h"
 #include "fmt/format.h"
 
+#include <io.h>
 #include <mutex>
 
 static DWORD ConvertToWinApi(const PageProtectionMode& mode)
@@ -72,6 +73,22 @@ void* HostSys::CreateSharedMemory(const char* name, size_t size)
 		static_cast<DWORD>(size >> 32), static_cast<DWORD>(size), StringUtil::UTF8StringToWideString(name).c_str()));
 }
 
+void* HostSys::CreateMappingFromFile(FILE* fd)
+{
+	return static_cast<void*>(CreateFileMappingW(reinterpret_cast<HANDLE>(_get_osfhandle(_fileno(fd))), NULL, PAGE_READWRITE,
+		0, 0, nullptr));
+}
+
+void* HostSys::MapMapping(void* handle, const PageProtectionMode& mode)
+{
+	return MapViewOfFile(static_cast<HANDLE>(handle), FILE_MAP_READ | FILE_MAP_WRITE, 0, 0, 0);
+}
+
+void HostSys::DestroyMapping(void* handle)
+{
+	CloseHandle(static_cast<HANDLE>(handle));
+}
+
 void HostSys::DestroySharedMemory(void* ptr)
 {
 	CloseHandle(static_cast<HANDLE>(ptr));

pcsx2/SIO/Memcard/MemoryCardFile.cpp

@@ -10,6 +10,7 @@
 #include "common/Console.h"
 #include "common/Error.h"
 #include "common/FileSystem.h"
+#include "common/HostSys.h"
 #include "common/Path.h"
 #include "common/StringUtil.h"
 
@@ -24,11 +25,6 @@
 
 #include <map>
 
-#ifdef _WIN32
-#include <windows.h>
-#include <io.h>
-#endif
-
 static constexpr int MCD_SIZE = 1024 * 8 * 16; // Legacy PSX card default size
 
 static constexpr int MC2_MBSIZE = 1024 * 528 * 2; // Size of a single megabyte of card data
@@ -163,6 +159,7 @@ class FileMemoryCard
 protected:
 	std::FILE* m_file[8] = {};
 	u8* m_mappings[8] = {};
+	void* m_mapping_handles[8] = {};
 
 	s64 m_fileSize[8] = {};
 	std::string m_filenames[8] = {};
@@ -345,20 +342,16 @@ void FileMemoryCard::Open()
 					Host::ReportErrorAsync("Memory Card Read Failed", "Error reading memory card.");
 			}
 
-#ifdef _WIN32
-			const int fd = _fileno(m_file[slot]);
-			// Doesn't leak, refcounted based on views
-			const HANDLE hMapping = CreateFileMapping(reinterpret_cast<HANDLE>(_get_osfhandle(fd)), nullptr, PAGE_READWRITE, 0, 0, nullptr);
-			if (!hMapping)
+			m_mapping_handles[slot] = HostSys::CreateMappingFromFile(m_file[slot]);
+			if (!m_mapping_handles[slot])
 			{
-				Console.Warning("CreateFileMapping failed: %d", GetLastError());
+				Console.Warning("CreateMappingFromFile failed!");
 			}
-			m_mappings[slot] = reinterpret_cast<u8*>(MapViewOfFile(hMapping, FILE_MAP_ALL_ACCESS, 0, 0, 0));
+			m_mappings[slot] = static_cast<u8*>(HostSys::MapMapping(m_mapping_handles[slot], PageAccess_ReadWrite()));
 			if (!m_mappings[slot])
 			{
-				Console.Warning("MapViewOfFile failed: %d", GetLastError());
+				Console.Warning("MapSharedMemory failed!");
 			}
-#endif
 		}
 	}
 }
@@ -386,13 +379,13 @@ void FileMemoryCard::Close()
 
 		m_filenames[slot] = {};
 		m_fileSize[slot] = -1;
-#ifdef _WIN32
+
 		if (m_mappings[slot])
 		{
-			UnmapViewOfFile(m_mappings[slot]);
+			HostSys::UnmapSharedMemory(m_mappings[slot], 0);
+			HostSys::DestroyMapping(m_mapping_handles[slot]);
 			m_mappings[slot] = nullptr;
 		}
-#endif
 	}
 }