diff --git a/Source/Core/Core/IOS/Device.h b/Source/Core/Core/IOS/Device.h
index c3ca6812c0..13aa85a316 100644
--- a/Source/Core/Core/IOS/Device.h
+++ b/Source/Core/Core/IOS/Device.h
@@ -23,6 +23,7 @@ enum ReturnCode : s32
   IPC_EACCES = -1,          // Permission denied
   IPC_EEXIST = -2,          // File exists
   IPC_EINVAL = -4,          // Invalid argument or fd
+  IPC_EMAX = -5,            // Too many file descriptors open
   IPC_ENOENT = -6,          // File not found
   IPC_EQUEUEFULL = -8,      // Queue full
   IPC_EIO = -12,            // ECC error
@@ -83,6 +84,7 @@ struct Request
 
 enum OpenMode : s32
 {
+  IOS_OPEN_NONE = 0,
   IOS_OPEN_READ = 1,
   IOS_OPEN_WRITE = 2,
   IOS_OPEN_RW = (IOS_OPEN_READ | IOS_OPEN_WRITE)
@@ -106,14 +108,15 @@ struct ReadWriteRequest final : Request
   explicit ReadWriteRequest(u32 address);
 };
 
+enum SeekMode : s32
+{
+  IOS_SEEK_SET = 0,
+  IOS_SEEK_CUR = 1,
+  IOS_SEEK_END = 2,
+};
+
 struct SeekRequest final : Request
 {
-  enum SeekMode
-  {
-    IOS_SEEK_SET = 0,
-    IOS_SEEK_CUR = 1,
-    IOS_SEEK_END = 2,
-  };
   u32 offset = 0;
   SeekMode mode = IOS_SEEK_SET;
   explicit SeekRequest(u32 address);
diff --git a/Source/Core/Core/IOS/FS/FileIO.cpp b/Source/Core/Core/IOS/FS/FileIO.cpp
index dd2f17af60..fd0361bc64 100644
--- a/Source/Core/Core/IOS/FS/FileIO.cpp
+++ b/Source/Core/Core/IOS/FS/FileIO.cpp
@@ -169,15 +169,15 @@ IPCCommandResult FileIO::Seek(const SeekRequest& request)
   u32 new_position = 0;
   switch (request.mode)
   {
-  case SeekRequest::IOS_SEEK_SET:
+  case IOS_SEEK_SET:
     new_position = request.offset;
     break;
 
-  case SeekRequest::IOS_SEEK_CUR:
+  case IOS_SEEK_CUR:
     new_position = m_SeekPos + request.offset;
     break;
 
-  case SeekRequest::IOS_SEEK_END:
+  case IOS_SEEK_END:
     new_position = file_size + request.offset;
     break;
 
diff --git a/Source/Core/Core/IOS/IOS.h b/Source/Core/Core/IOS/IOS.h
index 40db6c09b5..d9c6d8e785 100644
--- a/Source/Core/Core/IOS/IOS.h
+++ b/Source/Core/Core/IOS/IOS.h
@@ -55,6 +55,30 @@ enum IPCCommandType : u32
   IPC_REPLY = 8,
 };
 
+enum ProcessId : u32
+{
+  PID_KERNEL = 0,
+  PID_ES = 1,
+  PID_FS = 2,
+  PID_DI = 3,
+  PID_OH0 = 4,
+  PID_OH1 = 5,
+  PID_EHCI = 6,
+  PID_SDI = 7,
+  PID_USBETH = 8,
+  PID_NET = 9,
+  PID_WD = 10,
+  PID_WL = 11,
+  PID_KD = 12,
+  PID_NCD = 13,
+  PID_STM = 14,
+  PID_PPCBOOT = 15,
+  PID_SSL = 16,
+  PID_USB = 17,
+  PID_P2P = 18,
+  PID_UNKNOWN = 19,
+};
+
 // HLE for the IOS kernel: IPC, device management, syscalls, and Dolphin-specific, IOS-wide calls.
 class Kernel
 {