1 files changed, 75 insertions, 0 deletions
diff --git a/Ryujinx.Memory/MemoryManagementUnix.cs b/Ryujinx.Memory/MemoryManagementUnix.cs
new file mode 100644
index 00000000..81096867
--- /dev/null
+++ b/Ryujinx.Memory/MemoryManagementUnix.cs
@@ -0,0 +1,75 @@
+using Mono.Unix.Native;
+using System;
+using System.Collections.Concurrent;
+
+namespace Ryujinx.Memory
+{
+    static class MemoryManagementUnix
+    {
+        private static readonly ConcurrentDictionary<IntPtr, ulong> _allocations = new ConcurrentDictionary<IntPtr, ulong>();
+
+        public static IntPtr Allocate(ulong size)
+        {
+            return AllocateInternal(size, MmapProts.PROT_READ | MmapProts.PROT_WRITE);
+        }
+
+        public static IntPtr Reserve(ulong size)
+        {
+            return AllocateInternal(size, MmapProts.PROT_NONE);
+        }
+
+        private static IntPtr AllocateInternal(ulong size, MmapProts prot)
+        {
+            const MmapFlags flags = MmapFlags.MAP_PRIVATE | MmapFlags.MAP_ANONYMOUS;
+
+            IntPtr ptr = Syscall.mmap(IntPtr.Zero, size, prot, flags, -1, 0);
+
+            if (ptr == new IntPtr(-1L))
+            {
+                throw new OutOfMemoryException();
+            }
+
+            if (!_allocations.TryAdd(ptr, size))
+            {
+                // This should be impossible, kernel shouldn't return an already mapped address.
+                throw new InvalidOperationException();
+            }
+
+            return ptr;
+        }
+
+        public static bool Commit(IntPtr address, ulong size)
+        {
+            return Syscall.mprotect(address, size, MmapProts.PROT_READ | MmapProts.PROT_WRITE) == 0;
+        }
+
+        public static bool Reprotect(IntPtr address, ulong size, MemoryPermission permission)
+        {
+            return Syscall.mprotect(address, size, GetProtection(permission)) == 0;
+        }
+
+        private static MmapProts GetProtection(MemoryPermission permission)
+        {
+            return permission switch
+            {
+                MemoryPermission.None => MmapProts.PROT_NONE,
+                MemoryPermission.Read => MmapProts.PROT_READ,
+                MemoryPermission.ReadAndWrite => MmapProts.PROT_READ | MmapProts.PROT_WRITE,
+                MemoryPermission.ReadAndExecute => MmapProts.PROT_READ | MmapProts.PROT_EXEC,
+                MemoryPermission.ReadWriteExecute => MmapProts.PROT_READ | MmapProts.PROT_WRITE | MmapProts.PROT_EXEC,
+                MemoryPermission.Execute => MmapProts.PROT_EXEC,
+                _ => throw new MemoryProtectionException(permission)
+            };
+        }
+
+        public static bool Free(IntPtr address)
+        {
+            if (_allocations.TryRemove(address, out ulong size))
+            {
+                return Syscall.munmap(address, size) == 0;
+            }
+
+            return false;
+        }
+    }
+}
+\ No newline at end of file