33 files changed, 385 insertions, 300 deletions

diff --git a/src/common/bit_field.h b/src/common/bit_field.h
index 030f7caeb..0cc0a1be0 100644
--- a/src/common/bit_field.h
+++ b/src/common/bit_field.h
@@ -108,7 +108,7 @@
  * symptoms.
  */
 #pragma pack(1)
-template <std::size_t position, std::size_t bits, typename T>
+template <std::size_t Position, std::size_t Bits, typename T>
 struct BitField {
 private:
     // We hide the copy assigment operator here, because the default copy
@@ -117,7 +117,45 @@ private:
     // We don't delete it because we want BitField to be trivially copyable.
     BitField& operator=(const BitField&) = default;
 
+    // StorageType is T for non-enum types and the underlying type of T if
+    // T is an enumeration. Note that T is wrapped within an enable_if in the
+    // former case to workaround compile errors which arise when using
+    // std::underlying_type<T>::type directly.
+    using StorageType = typename std::conditional_t<std::is_enum<T>::value, std::underlying_type<T>,
+                                                    std::enable_if<true, T>>::type;
+
+    // Unsigned version of StorageType
+    using StorageTypeU = std::make_unsigned_t<StorageType>;
+
 public:
+    /// Constants to allow limited introspection of fields if needed
+    static constexpr size_t position = Position;
+    static constexpr size_t bits = Bits;
+    static constexpr StorageType mask = (((StorageTypeU)~0) >> (8 * sizeof(T) - bits)) << position;
+
+    /**
+     * Formats a value by masking and shifting it according to the field parameters. A value
+     * containing several bitfields can be assembled by formatting each of their values and ORing
+     * the results together.
+     */
+    static constexpr FORCE_INLINE StorageType FormatValue(const T& value) {
+        return ((StorageType)value << position) & mask;
+    }
+
+    /**
+     * Extracts a value from the passed storage. In most situations prefer use the member functions
+     * (such as Value() or operator T), but this can be used to extract a value from a bitfield
+     * union in a constexpr context.
+     */
+    static constexpr FORCE_INLINE T ExtractValue(const StorageType& storage) {
+        if (std::numeric_limits<T>::is_signed) {
+            std::size_t shift = 8 * sizeof(T) - bits;
+            return (T)((storage << (shift - position)) >> shift);
+        } else {
+            return (T)((storage & mask) >> position);
+        }
+    }
+
     // This constructor and assignment operator might be considered ambiguous:
     // Would they initialize the storage or just the bitfield?
     // Hence, delete them. Use the Assign method to set bitfield values!
@@ -126,23 +164,18 @@ public:
 
     // Force default constructor to be created
     // so that we can use this within unions
-    BitField() = default;
+    constexpr BitField() = default;
 
     FORCE_INLINE operator T() const {
         return Value();
     }
 
     FORCE_INLINE void Assign(const T& value) {
-        storage = (storage & ~GetMask()) | (((StorageType)value << position) & GetMask());
+        storage = (storage & ~mask) | FormatValue(value);
     }
 
     FORCE_INLINE T Value() const {
-        if (std::numeric_limits<T>::is_signed) {
-            std::size_t shift = 8 * sizeof(T) - bits;
-            return (T)((storage << (shift - position)) >> shift);
-        } else {
-            return (T)((storage & GetMask()) >> position);
-        }
+        return ExtractValue(storage);
     }
 
     // TODO: we may want to change this to explicit operator bool() if it's bug-free in VS2015
@@ -151,20 +184,6 @@ public:
     }
 
 private:
-    // StorageType is T for non-enum types and the underlying type of T if
-    // T is an enumeration. Note that T is wrapped within an enable_if in the
-    // former case to workaround compile errors which arise when using
-    // std::underlying_type<T>::type directly.
-    typedef typename std::conditional<std::is_enum<T>::value, std::underlying_type<T>,
-                                      std::enable_if<true, T>>::type::type StorageType;
-
-    // Unsigned version of StorageType
-    typedef typename std::make_unsigned<StorageType>::type StorageTypeU;
-
-    FORCE_INLINE StorageType GetMask() const {
-        return (((StorageTypeU)~0) >> (8 * sizeof(T) - bits)) << position;
-    }
-
     StorageType storage;
 
     static_assert(bits + position <= 8 * sizeof(T), "Bitfield out of range");
diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
index 57504529f..b19335fe1 100644
--- a/src/core/CMakeLists.txt
+++ b/src/core/CMakeLists.txt
@@ -231,6 +231,7 @@ set(HEADERS
             hle/kernel/address_arbiter.h
             hle/kernel/client_port.h
             hle/kernel/client_session.h
+            hle/kernel/errors.h
             hle/kernel/event.h
             hle/kernel/kernel.h
             hle/kernel/memory.h
diff --git a/src/core/file_sys/archive_extsavedata.cpp b/src/core/file_sys/archive_extsavedata.cpp
index f454e7840..4867c9d17 100644
--- a/src/core/file_sys/archive_extsavedata.cpp
+++ b/src/core/file_sys/archive_extsavedata.cpp
@@ -38,8 +38,7 @@ public:
     ResultVal<size_t> Write(u64 offset, size_t length, bool flush,
                             const u8* buffer) const override {
         if (offset > size) {
-            return ResultCode(ErrorDescription::FS_WriteBeyondEnd, ErrorModule::FS,
-                              ErrorSummary::InvalidArgument, ErrorLevel::Usage);
+            return ERR_WRITE_BEYOND_END;
         } else if (offset == size) {
             return MakeResult<size_t>(0);
         }
@@ -191,11 +190,9 @@ ResultVal<std::unique_ptr<ArchiveBackend>> ArchiveFactory_ExtSaveData::Open(cons
         // TODO(Subv): Verify the archive behavior of SharedExtSaveData compared to ExtSaveData.
         // ExtSaveData seems to return FS_NotFound (120) when the archive doesn't exist.
         if (!shared) {
-            return ResultCode(ErrorDescription::FS_NotFound, ErrorModule::FS,
-                              ErrorSummary::InvalidState, ErrorLevel::Status);
+            return ERR_NOT_FOUND_INVALID_STATE;
         } else {
-            return ResultCode(ErrorDescription::FS_NotFormatted, ErrorModule::FS,
-                              ErrorSummary::InvalidState, ErrorLevel::Status);
+            return ERR_NOT_FORMATTED;
         }
     }
     auto archive = std::make_unique<ExtSaveDataArchive>(fullpath);
@@ -230,8 +227,7 @@ ResultVal<ArchiveFormatInfo> ArchiveFactory_ExtSaveData::GetFormatInfo(const Pat
     if (!file.IsOpen()) {
         LOG_ERROR(Service_FS, "Could not open metadata information for archive");
         // TODO(Subv): Verify error code
-        return ResultCode(ErrorDescription::FS_NotFormatted, ErrorModule::FS,
-                          ErrorSummary::InvalidState, ErrorLevel::Status);
+        return ERR_NOT_FORMATTED;
     }
 
     ArchiveFormatInfo info = {};
diff --git a/src/core/file_sys/archive_source_sd_savedata.cpp b/src/core/file_sys/archive_source_sd_savedata.cpp
index f31a68038..a7e331724 100644
--- a/src/core/file_sys/archive_source_sd_savedata.cpp
+++ b/src/core/file_sys/archive_source_sd_savedata.cpp
@@ -6,6 +6,7 @@
 #include "common/logging/log.h"
 #include "common/string_util.h"
 #include "core/file_sys/archive_source_sd_savedata.h"
+#include "core/file_sys/errors.h"
 #include "core/file_sys/savedata_archive.h"
 #include "core/hle/service/fs/archive.h"
 
@@ -49,8 +50,7 @@ ResultVal<std::unique_ptr<ArchiveBackend>> ArchiveSource_SDSaveData::Open(u64 pr
         // save file/directory structure expected by the game has not yet been initialized.
         // Returning the NotFormatted error code will signal the game to provision the SaveData
         // archive with the files and folders that it expects.
-        return ResultCode(ErrorDescription::FS_NotFormatted, ErrorModule::FS,
-                          ErrorSummary::InvalidState, ErrorLevel::Status);
+        return ERR_NOT_FORMATTED;
     }
 
     auto archive = std::make_unique<SaveDataArchive>(std::move(concrete_mount_point));
@@ -81,8 +81,7 @@ ResultVal<ArchiveFormatInfo> ArchiveSource_SDSaveData::GetFormatInfo(u64 program
     if (!file.IsOpen()) {
         LOG_ERROR(Service_FS, "Could not open metadata information for archive");
         // TODO(Subv): Verify error code
-        return ResultCode(ErrorDescription::FS_NotFormatted, ErrorModule::FS,
-                          ErrorSummary::InvalidState, ErrorLevel::Status);
+        return ERR_NOT_FORMATTED;
     }
 
     ArchiveFormatInfo info = {};
diff --git a/src/core/file_sys/archive_systemsavedata.cpp b/src/core/file_sys/archive_systemsavedata.cpp
index 8986b5c0e..81423bffd 100644
--- a/src/core/file_sys/archive_systemsavedata.cpp
+++ b/src/core/file_sys/archive_systemsavedata.cpp
@@ -9,6 +9,7 @@
 #include "common/file_util.h"
 #include "common/string_util.h"
 #include "core/file_sys/archive_systemsavedata.h"
+#include "core/file_sys/errors.h"
 #include "core/file_sys/savedata_archive.h"
 #include "core/hle/service/fs/archive.h"
 
@@ -53,8 +54,7 @@ ResultVal<std::unique_ptr<ArchiveBackend>> ArchiveFactory_SystemSaveData::Open(c
     std::string fullpath = GetSystemSaveDataPath(base_path, path);
     if (!FileUtil::Exists(fullpath)) {
         // TODO(Subv): Check error code, this one is probably wrong
-        return ResultCode(ErrorDescription::FS_NotFormatted, ErrorModule::FS,
-                          ErrorSummary::InvalidState, ErrorLevel::Status);
+        return ERR_NOT_FORMATTED;
     }
     auto archive = std::make_unique<SaveDataArchive>(fullpath);
     return MakeResult<std::unique_ptr<ArchiveBackend>>(std::move(archive));
diff --git a/src/core/file_sys/disk_archive.cpp b/src/core/file_sys/disk_archive.cpp
index a243d9a13..98d80aabc 100644
--- a/src/core/file_sys/disk_archive.cpp
+++ b/src/core/file_sys/disk_archive.cpp
@@ -9,6 +9,7 @@
 #include "common/file_util.h"
 #include "common/logging/log.h"
 #include "core/file_sys/disk_archive.h"
+#include "core/file_sys/errors.h"
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 // FileSys namespace
@@ -17,8 +18,7 @@ namespace FileSys {
 
 ResultVal<size_t> DiskFile::Read(const u64 offset, const size_t length, u8* buffer) const {
     if (!mode.read_flag)
-        return ResultCode(ErrorDescription::FS_InvalidOpenFlags, ErrorModule::FS,
-                          ErrorSummary::Canceled, ErrorLevel::Status);
+        return ERROR_INVALID_OPEN_FLAGS;
 
     file->Seek(offset, SEEK_SET);
     return MakeResult<size_t>(file->ReadBytes(buffer, length));
@@ -27,8 +27,7 @@ ResultVal<size_t> DiskFile::Read(const u64 offset, const size_t length, u8* buff
 ResultVal<size_t> DiskFile::Write(const u64 offset, const size_t length, const bool flush,
                                   const u8* buffer) const {
     if (!mode.write_flag)
-        return ResultCode(ErrorDescription::FS_InvalidOpenFlags, ErrorModule::FS,
-                          ErrorSummary::Canceled, ErrorLevel::Status);
+        return ERROR_INVALID_OPEN_FLAGS;
 
     file->Seek(offset, SEEK_SET);
     size_t written = file->WriteBytes(buffer, length);
diff --git a/src/core/file_sys/errors.h b/src/core/file_sys/errors.h
index 9fc8d753b..a974bc775 100644
--- a/src/core/file_sys/errors.h
+++ b/src/core/file_sys/errors.h
@@ -2,52 +2,93 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
+#pragma once
+
 #include "core/hle/result.h"
 
 namespace FileSys {
 
-const ResultCode ERROR_INVALID_PATH(ErrorDescription::FS_InvalidPath, ErrorModule::FS,
-                                    ErrorSummary::InvalidArgument, ErrorLevel::Usage);
-const ResultCode ERROR_UNSUPPORTED_OPEN_FLAGS(ErrorDescription::FS_UnsupportedOpenFlags,
-                                              ErrorModule::FS, ErrorSummary::NotSupported,
-                                              ErrorLevel::Usage);
-const ResultCode ERROR_INVALID_OPEN_FLAGS(ErrorDescription::FS_InvalidOpenFlags, ErrorModule::FS,
-                                          ErrorSummary::Canceled, ErrorLevel::Status);
-const ResultCode ERROR_INVALID_READ_FLAG(ErrorDescription::FS_InvalidReadFlag, ErrorModule::FS,
-                                         ErrorSummary::InvalidArgument, ErrorLevel::Usage);
-const ResultCode ERROR_FILE_NOT_FOUND(ErrorDescription::FS_FileNotFound, ErrorModule::FS,
-                                      ErrorSummary::NotFound, ErrorLevel::Status);
-const ResultCode ERROR_PATH_NOT_FOUND(ErrorDescription::FS_PathNotFound, ErrorModule::FS,
-                                      ErrorSummary::NotFound, ErrorLevel::Status);
-const ResultCode ERROR_NOT_FOUND(ErrorDescription::FS_NotFound, ErrorModule::FS,
-                                 ErrorSummary::NotFound, ErrorLevel::Status);
-const ResultCode ERROR_UNEXPECTED_FILE_OR_DIRECTORY(ErrorDescription::FS_UnexpectedFileOrDirectory,
-                                                    ErrorModule::FS, ErrorSummary::NotSupported,
-                                                    ErrorLevel::Usage);
-const ResultCode ERROR_UNEXPECTED_FILE_OR_DIRECTORY_SDMC(ErrorDescription::FS_NotAFile,
-                                                         ErrorModule::FS, ErrorSummary::Canceled,
-                                                         ErrorLevel::Status);
-const ResultCode ERROR_DIRECTORY_ALREADY_EXISTS(ErrorDescription::FS_DirectoryAlreadyExists,
-                                                ErrorModule::FS, ErrorSummary::NothingHappened,
-                                                ErrorLevel::Status);
-const ResultCode ERROR_FILE_ALREADY_EXISTS(ErrorDescription::FS_FileAlreadyExists, ErrorModule::FS,
-                                           ErrorSummary::NothingHappened, ErrorLevel::Status);
-const ResultCode ERROR_ALREADY_EXISTS(ErrorDescription::FS_AlreadyExists, ErrorModule::FS,
-                                      ErrorSummary::NothingHappened, ErrorLevel::Status);
-const ResultCode ERROR_DIRECTORY_NOT_EMPTY(ErrorDescription::FS_DirectoryNotEmpty, ErrorModule::FS,
-                                           ErrorSummary::Canceled, ErrorLevel::Status);
-const ResultCode ERROR_GAMECARD_NOT_INSERTED(ErrorDescription::FS_GameCardNotInserted,
-                                             ErrorModule::FS, ErrorSummary::NotFound,
-                                             ErrorLevel::Status);
-const ResultCode ERROR_INCORRECT_EXEFS_READ_SIZE(ErrorDescription::FS_IncorrectExeFSReadSize,
-                                                 ErrorModule::FS, ErrorSummary::NotSupported,
-                                                 ErrorLevel::Usage);
-const ResultCode ERROR_ROMFS_NOT_FOUND(ErrorDescription::FS_RomFSNotFound, ErrorModule::FS,
-                                       ErrorSummary::NotFound, ErrorLevel::Status);
-const ResultCode ERROR_COMMAND_NOT_ALLOWED(ErrorDescription::FS_CommandNotAllowed, ErrorModule::FS,
-                                           ErrorSummary::WrongArgument, ErrorLevel::Permanent);
-const ResultCode ERROR_EXEFS_SECTION_NOT_FOUND(ErrorDescription::FS_ExeFSSectionNotFound,
-                                               ErrorModule::FS, ErrorSummary::NotFound,
-                                               ErrorLevel::Status);
+namespace ErrCodes {
+enum {
+    RomFSNotFound = 100,
+    ArchiveNotMounted = 101,
+    FileNotFound = 112,
+    PathNotFound = 113,
+    GameCardNotInserted = 141,
+    NotFound = 120,
+    FileAlreadyExists = 180,
+    DirectoryAlreadyExists = 185,
+    AlreadyExists = 190,
+    InvalidOpenFlags = 230,
+    DirectoryNotEmpty = 240,
+    NotAFile = 250,
+    NotFormatted = 340, ///< This is used by the FS service when creating a SaveData archive
+    ExeFSSectionNotFound = 567,
+    CommandNotAllowed = 630,
+    InvalidReadFlag = 700,
+    InvalidPath = 702,
+    WriteBeyondEnd = 705,
+    UnsupportedOpenFlags = 760,
+    IncorrectExeFSReadSize = 761,
+    UnexpectedFileOrDirectory = 770,
+};
+}
+
+constexpr ResultCode ERROR_INVALID_PATH(ErrCodes::InvalidPath, ErrorModule::FS,
+                                        ErrorSummary::InvalidArgument, ErrorLevel::Usage);
+constexpr ResultCode ERROR_UNSUPPORTED_OPEN_FLAGS(ErrCodes::UnsupportedOpenFlags, ErrorModule::FS,
+                                                  ErrorSummary::NotSupported, ErrorLevel::Usage);
+constexpr ResultCode ERROR_INVALID_OPEN_FLAGS(ErrCodes::InvalidOpenFlags, ErrorModule::FS,
+                                              ErrorSummary::Canceled, ErrorLevel::Status);
+constexpr ResultCode ERROR_INVALID_READ_FLAG(ErrCodes::InvalidReadFlag, ErrorModule::FS,
+                                             ErrorSummary::InvalidArgument, ErrorLevel::Usage);
+constexpr ResultCode ERROR_FILE_NOT_FOUND(ErrCodes::FileNotFound, ErrorModule::FS,
+                                          ErrorSummary::NotFound, ErrorLevel::Status);
+constexpr ResultCode ERROR_PATH_NOT_FOUND(ErrCodes::PathNotFound, ErrorModule::FS,
+                                          ErrorSummary::NotFound, ErrorLevel::Status);
+constexpr ResultCode ERROR_NOT_FOUND(ErrCodes::NotFound, ErrorModule::FS, ErrorSummary::NotFound,
+                                     ErrorLevel::Status);
+constexpr ResultCode ERROR_UNEXPECTED_FILE_OR_DIRECTORY(ErrCodes::UnexpectedFileOrDirectory,
+                                                        ErrorModule::FS, ErrorSummary::NotSupported,
+                                                        ErrorLevel::Usage);
+constexpr ResultCode ERROR_UNEXPECTED_FILE_OR_DIRECTORY_SDMC(ErrCodes::NotAFile, ErrorModule::FS,
+                                                             ErrorSummary::Canceled,
+                                                             ErrorLevel::Status);
+constexpr ResultCode ERROR_DIRECTORY_ALREADY_EXISTS(ErrCodes::DirectoryAlreadyExists,
+                                                    ErrorModule::FS, ErrorSummary::NothingHappened,
+                                                    ErrorLevel::Status);
+constexpr ResultCode ERROR_FILE_ALREADY_EXISTS(ErrCodes::FileAlreadyExists, ErrorModule::FS,
+                                               ErrorSummary::NothingHappened, ErrorLevel::Status);
+constexpr ResultCode ERROR_ALREADY_EXISTS(ErrCodes::AlreadyExists, ErrorModule::FS,
+                                          ErrorSummary::NothingHappened, ErrorLevel::Status);
+constexpr ResultCode ERROR_DIRECTORY_NOT_EMPTY(ErrCodes::DirectoryNotEmpty, ErrorModule::FS,
+                                               ErrorSummary::Canceled, ErrorLevel::Status);
+constexpr ResultCode ERROR_GAMECARD_NOT_INSERTED(ErrCodes::GameCardNotInserted, ErrorModule::FS,
+                                                 ErrorSummary::NotFound, ErrorLevel::Status);
+constexpr ResultCode ERROR_INCORRECT_EXEFS_READ_SIZE(ErrCodes::IncorrectExeFSReadSize,
+                                                     ErrorModule::FS, ErrorSummary::NotSupported,
+                                                     ErrorLevel::Usage);
+constexpr ResultCode ERROR_ROMFS_NOT_FOUND(ErrCodes::RomFSNotFound, ErrorModule::FS,
+                                           ErrorSummary::NotFound, ErrorLevel::Status);
+constexpr ResultCode ERROR_COMMAND_NOT_ALLOWED(ErrCodes::CommandNotAllowed, ErrorModule::FS,
+                                               ErrorSummary::WrongArgument, ErrorLevel::Permanent);
+constexpr ResultCode ERROR_EXEFS_SECTION_NOT_FOUND(ErrCodes::ExeFSSectionNotFound, ErrorModule::FS,
+                                                   ErrorSummary::NotFound, ErrorLevel::Status);
+
+/// Returned when a function is passed an invalid archive handle.
+constexpr ResultCode ERR_INVALID_ARCHIVE_HANDLE(ErrCodes::ArchiveNotMounted, ErrorModule::FS,
+                                                ErrorSummary::NotFound,
+                                                ErrorLevel::Status); // 0xC8804465
+constexpr ResultCode ERR_WRITE_BEYOND_END(ErrCodes::WriteBeyondEnd, ErrorModule::FS,
+                                          ErrorSummary::InvalidArgument, ErrorLevel::Usage);
+
+/**
+ * Variant of ERROR_NOT_FOUND returned in some places in the code. Unknown if these usages are
+ * correct or a bug.
+ */
+constexpr ResultCode ERR_NOT_FOUND_INVALID_STATE(ErrCodes::NotFound, ErrorModule::FS,
+                                                 ErrorSummary::InvalidState, ErrorLevel::Status);
+constexpr ResultCode ERR_NOT_FORMATTED(ErrCodes::NotFormatted, ErrorModule::FS,
+                                       ErrorSummary::InvalidState, ErrorLevel::Status);
 
 } // namespace FileSys
diff --git a/src/core/hle/function_wrappers.h b/src/core/hle/function_wrappers.h
index f6eb900f0..18b6e7017 100644
--- a/src/core/hle/function_wrappers.h
+++ b/src/core/hle/function_wrappers.h
@@ -53,7 +53,7 @@ void Wrap() {
     FuncReturn(retval);
 }
 
-template <ResultCode func(u32*, s32, u32, u32, u32, s32)>
+template <ResultCode func(u32*, u32, u32, u32, u32, s32)>
 void Wrap() {
     u32 param_1 = 0;
     u32 retval = func(&param_1, PARAM(0), PARAM(1), PARAM(2), PARAM(3), PARAM(4)).raw;
diff --git a/src/core/hle/ipc.h b/src/core/hle/ipc.h
index 3a5d481a5..303ca090d 100644
--- a/src/core/hle/ipc.h
+++ b/src/core/hle/ipc.h
@@ -5,6 +5,7 @@
 #pragma once
 
 #include "common/common_types.h"
+#include "core/hle/kernel/errors.h"
 #include "core/hle/kernel/thread.h"
 #include "core/memory.h"
 
@@ -43,6 +44,12 @@ inline u32* GetStaticBuffers(const int offset = 0) {
 
 namespace IPC {
 
+// These errors are commonly returned by invalid IPC translations, so alias them here for
+// convenience.
+// TODO(yuriks): These will probably go away once translation is implemented inside the kernel.
+using Kernel::ERR_INVALID_BUFFER_DESCRIPTOR;
+constexpr auto ERR_INVALID_HANDLE = Kernel::ERR_INVALID_HANDLE_OS;
+
 enum DescriptorType : u32 {
     // Buffer related desciptors types (mask : 0x0F)
     StaticBuffer = 0x02,
diff --git a/src/core/hle/kernel/address_arbiter.cpp b/src/core/hle/kernel/address_arbiter.cpp
index 01fab123e..776d342f0 100644
--- a/src/core/hle/kernel/address_arbiter.cpp
+++ b/src/core/hle/kernel/address_arbiter.cpp
@@ -5,6 +5,7 @@
 #include "common/common_types.h"
 #include "common/logging/log.h"
 #include "core/hle/kernel/address_arbiter.h"
+#include "core/hle/kernel/errors.h"
 #include "core/hle/kernel/thread.h"
 #include "core/memory.h"
 
@@ -74,8 +75,7 @@ ResultCode AddressArbiter::ArbitrateAddress(ArbitrationType type, VAddr address,
 
     default:
         LOG_ERROR(Kernel, "unknown type=%d", type);
-        return ResultCode(ErrorDescription::InvalidEnumValue, ErrorModule::Kernel,
-                          ErrorSummary::WrongArgument, ErrorLevel::Usage);
+        return ERR_INVALID_ENUM_VALUE_FND;
     }
 
     // The calls that use a timeout seem to always return a Timeout error even if they did not put
@@ -83,8 +83,7 @@ ResultCode AddressArbiter::ArbitrateAddress(ArbitrationType type, VAddr address,
     if (type == ArbitrationType::WaitIfLessThanWithTimeout ||
         type == ArbitrationType::DecrementAndWaitIfLessThanWithTimeout) {
 
-        return ResultCode(ErrorDescription::Timeout, ErrorModule::OS, ErrorSummary::StatusChanged,
-                          ErrorLevel::Info);
+        return RESULT_TIMEOUT;
     }
     return RESULT_SUCCESS;
 }
diff --git a/src/core/hle/kernel/client_port.cpp b/src/core/hle/kernel/client_port.cpp
index ddcf4c916..03ffdece1 100644
--- a/src/core/hle/kernel/client_port.cpp
+++ b/src/core/hle/kernel/client_port.cpp
@@ -5,6 +5,7 @@
 #include "common/assert.h"
 #include "core/hle/kernel/client_port.h"
 #include "core/hle/kernel/client_session.h"
+#include "core/hle/kernel/errors.h"
 #include "core/hle/kernel/kernel.h"
 #include "core/hle/kernel/server_port.h"
 #include "core/hle/kernel/server_session.h"
@@ -19,8 +20,7 @@ ResultVal<SharedPtr<ClientSession>> ClientPort::Connect() {
     // AcceptSession before returning from this call.
 
     if (active_sessions >= max_sessions) {
-        return ResultCode(ErrorDescription::MaxConnectionsReached, ErrorModule::OS,
-                          ErrorSummary::WouldBlock, ErrorLevel::Temporary);
+        return ERR_MAX_CONNECTIONS_REACHED;
     }
     active_sessions++;
 
diff --git a/src/core/hle/kernel/client_session.cpp b/src/core/hle/kernel/client_session.cpp
index e297b7464..783b1c061 100644
--- a/src/core/hle/kernel/client_session.cpp
+++ b/src/core/hle/kernel/client_session.cpp
@@ -30,8 +30,7 @@ ResultCode ClientSession::SendSyncRequest() {
     if (parent->server)
         return parent->server->HandleSyncRequest();
 
-    return ResultCode(ErrorDescription::SessionClosedByRemote, ErrorModule::OS,
-                      ErrorSummary::Canceled, ErrorLevel::Status);
+    return ERR_SESSION_CLOSED_BY_REMOTE;
 }
 
 } // namespace
diff --git a/src/core/hle/kernel/errors.h b/src/core/hle/kernel/errors.h
new file mode 100644
index 000000000..b3b60e7df
--- /dev/null
+++ b/src/core/hle/kernel/errors.h
@@ -0,0 +1,98 @@
+// Copyright 2017 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include "core/hle/result.h"
+
+namespace Kernel {
+
+namespace ErrCodes {
+enum {
+    OutOfHandles = 19,
+    SessionClosedByRemote = 26,
+    PortNameTooLong = 30,
+    WrongPermission = 46,
+    InvalidBufferDescriptor = 48,
+    MaxConnectionsReached = 52,
+};
+}
+
+// WARNING: The kernel is quite inconsistent in it's usage of errors code. Make sure to always
+// double check that the code matches before re-using the constant.
+
+constexpr ResultCode ERR_OUT_OF_HANDLES(ErrCodes::OutOfHandles, ErrorModule::Kernel,
+                                        ErrorSummary::OutOfResource,
+                                        ErrorLevel::Permanent); // 0xD8600413
+constexpr ResultCode ERR_SESSION_CLOSED_BY_REMOTE(ErrCodes::SessionClosedByRemote, ErrorModule::OS,
+                                                  ErrorSummary::Canceled,
+                                                  ErrorLevel::Status); // 0xC920181A
+constexpr ResultCode ERR_PORT_NAME_TOO_LONG(ErrCodes::PortNameTooLong, ErrorModule::OS,
+                                            ErrorSummary::InvalidArgument,
+                                            ErrorLevel::Usage); // 0xE0E0181E
+constexpr ResultCode ERR_WRONG_PERMISSION(ErrCodes::WrongPermission, ErrorModule::OS,
+                                          ErrorSummary::WrongArgument, ErrorLevel::Permanent);
+constexpr ResultCode ERR_INVALID_BUFFER_DESCRIPTOR(ErrCodes::InvalidBufferDescriptor,
+                                                   ErrorModule::OS, ErrorSummary::WrongArgument,
+                                                   ErrorLevel::Permanent);
+constexpr ResultCode ERR_MAX_CONNECTIONS_REACHED(ErrCodes::MaxConnectionsReached, ErrorModule::OS,
+                                                 ErrorSummary::WouldBlock,
+                                                 ErrorLevel::Temporary); // 0xD0401834
+
+constexpr ResultCode ERR_NOT_AUTHORIZED(ErrorDescription::NotAuthorized, ErrorModule::OS,
+                                        ErrorSummary::WrongArgument,
+                                        ErrorLevel::Permanent); // 0xD9001BEA
+constexpr ResultCode ERR_INVALID_ENUM_VALUE(ErrorDescription::InvalidEnumValue, ErrorModule::Kernel,
+                                            ErrorSummary::InvalidArgument,
+                                            ErrorLevel::Permanent); // 0xD8E007ED
+constexpr ResultCode ERR_INVALID_ENUM_VALUE_FND(ErrorDescription::InvalidEnumValue,
+                                                ErrorModule::FND, ErrorSummary::InvalidArgument,
+                                                ErrorLevel::Permanent); // 0xD8E093ED
+constexpr ResultCode ERR_INVALID_COMBINATION(ErrorDescription::InvalidCombination, ErrorModule::OS,
+                                             ErrorSummary::InvalidArgument,
+                                             ErrorLevel::Usage); // 0xE0E01BEE
+constexpr ResultCode ERR_INVALID_COMBINATION_KERNEL(ErrorDescription::InvalidCombination,
+                                                    ErrorModule::Kernel,
+                                                    ErrorSummary::WrongArgument,
+                                                    ErrorLevel::Permanent); // 0xD90007EE
+constexpr ResultCode ERR_MISALIGNED_ADDRESS(ErrorDescription::MisalignedAddress, ErrorModule::OS,
+                                            ErrorSummary::InvalidArgument,
+                                            ErrorLevel::Usage); // 0xE0E01BF1
+constexpr ResultCode ERR_MISALIGNED_SIZE(ErrorDescription::MisalignedSize, ErrorModule::OS,
+                                         ErrorSummary::InvalidArgument,
+                                         ErrorLevel::Usage); // 0xE0E01BF2
+constexpr ResultCode ERR_OUT_OF_MEMORY(ErrorDescription::OutOfMemory, ErrorModule::Kernel,
+                                       ErrorSummary::OutOfResource,
+                                       ErrorLevel::Permanent); // 0xD86007F3
+constexpr ResultCode ERR_NOT_IMPLEMENTED(ErrorDescription::NotImplemented, ErrorModule::OS,
+                                         ErrorSummary::InvalidArgument,
+                                         ErrorLevel::Usage); // 0xE0E01BF4
+constexpr ResultCode ERR_INVALID_ADDRESS(ErrorDescription::InvalidAddress, ErrorModule::OS,
+                                         ErrorSummary::InvalidArgument,
+                                         ErrorLevel::Usage); // 0xE0E01BF5
+constexpr ResultCode ERR_INVALID_ADDRESS_STATE(ErrorDescription::InvalidAddress, ErrorModule::OS,
+                                               ErrorSummary::InvalidState,
+                                               ErrorLevel::Usage); // 0xE0A01BF5
+constexpr ResultCode ERR_INVALID_POINTER(ErrorDescription::InvalidPointer, ErrorModule::Kernel,
+                                         ErrorSummary::InvalidArgument,
+                                         ErrorLevel::Permanent); // 0xD8E007F6
+constexpr ResultCode ERR_INVALID_HANDLE(ErrorDescription::InvalidHandle, ErrorModule::Kernel,
+                                        ErrorSummary::InvalidArgument,
+                                        ErrorLevel::Permanent); // 0xD8E007F7
+/// Alternate code returned instead of ERR_INVALID_HANDLE in some code paths.
+constexpr ResultCode ERR_INVALID_HANDLE_OS(ErrorDescription::InvalidHandle, ErrorModule::OS,
+                                           ErrorSummary::WrongArgument,
+                                           ErrorLevel::Permanent); // 0xD9001BF7
+constexpr ResultCode ERR_NOT_FOUND(ErrorDescription::NotFound, ErrorModule::Kernel,
+                                   ErrorSummary::NotFound, ErrorLevel::Permanent); // 0xD88007FA
+constexpr ResultCode ERR_OUT_OF_RANGE(ErrorDescription::OutOfRange, ErrorModule::OS,
+                                      ErrorSummary::InvalidArgument,
+                                      ErrorLevel::Usage); // 0xE0E01BFD
+constexpr ResultCode ERR_OUT_OF_RANGE_KERNEL(ErrorDescription::OutOfRange, ErrorModule::Kernel,
+                                             ErrorSummary::InvalidArgument,
+                                             ErrorLevel::Permanent); // 0xD8E007FD
+constexpr ResultCode RESULT_TIMEOUT(ErrorDescription::Timeout, ErrorModule::OS,
+                                    ErrorSummary::StatusChanged, ErrorLevel::Info);
+
+} // namespace Kernel
diff --git a/src/core/hle/kernel/kernel.cpp b/src/core/hle/kernel/kernel.cpp
index f599916f0..7f84e01aa 100644
--- a/src/core/hle/kernel/kernel.cpp
+++ b/src/core/hle/kernel/kernel.cpp
@@ -6,6 +6,7 @@
 #include "common/assert.h"
 #include "common/logging/log.h"
 #include "core/hle/config_mem.h"
+#include "core/hle/kernel/errors.h"
 #include "core/hle/kernel/kernel.h"
 #include "core/hle/kernel/memory.h"
 #include "core/hle/kernel/process.h"
diff --git a/src/core/hle/kernel/kernel.h b/src/core/hle/kernel/kernel.h
index bb8b99bb5..94f2025a0 100644
--- a/src/core/hle/kernel/kernel.h
+++ b/src/core/hle/kernel/kernel.h
@@ -19,13 +19,6 @@ using Handle = u32;
 
 class Thread;
 
-// TODO: Verify code
-const ResultCode ERR_OUT_OF_HANDLES(ErrorDescription::OutOfMemory, ErrorModule::Kernel,
-                                    ErrorSummary::OutOfResource, ErrorLevel::Temporary);
-// TOOD: Verify code
-const ResultCode ERR_INVALID_HANDLE(ErrorDescription::InvalidHandle, ErrorModule::Kernel,
-                                    ErrorSummary::InvalidArgument, ErrorLevel::Permanent);
-
 enum KernelHandle : Handle {
     CurrentThread = 0xFFFF8000,
     CurrentProcess = 0xFFFF8001,
diff --git a/src/core/hle/kernel/process.cpp b/src/core/hle/kernel/process.cpp
index 32cb25fb7..1c31ec950 100644
--- a/src/core/hle/kernel/process.cpp
+++ b/src/core/hle/kernel/process.cpp
@@ -6,6 +6,7 @@
 #include "common/assert.h"
 #include "common/common_funcs.h"
 #include "common/logging/log.h"
+#include "core/hle/kernel/errors.h"
 #include "core/hle/kernel/memory.h"
 #include "core/hle/kernel/process.h"
 #include "core/hle/kernel/resource_limit.h"
diff --git a/src/core/hle/kernel/semaphore.cpp b/src/core/hle/kernel/semaphore.cpp
index 8bda2f75d..fcf586728 100644
--- a/src/core/hle/kernel/semaphore.cpp
+++ b/src/core/hle/kernel/semaphore.cpp
@@ -3,6 +3,7 @@
 // Refer to the license.txt file included.
 
 #include "common/assert.h"
+#include "core/hle/kernel/errors.h"
 #include "core/hle/kernel/kernel.h"
 #include "core/hle/kernel/semaphore.h"
 #include "core/hle/kernel/thread.h"
@@ -16,8 +17,7 @@ ResultVal<SharedPtr<Semaphore>> Semaphore::Create(s32 initial_count, s32 max_cou
                                                   std::string name) {
 
     if (initial_count > max_count)
-        return ResultCode(ErrorDescription::InvalidCombination, ErrorModule::Kernel,
-                          ErrorSummary::WrongArgument, ErrorLevel::Permanent);
+        return ERR_INVALID_COMBINATION_KERNEL;
 
     SharedPtr<Semaphore> semaphore(new Semaphore);
 
@@ -42,8 +42,7 @@ void Semaphore::Acquire(Thread* thread) {
 
 ResultVal<s32> Semaphore::Release(s32 release_count) {
     if (max_count - available_count < release_count)
-        return ResultCode(ErrorDescription::OutOfRange, ErrorModule::Kernel,
-                          ErrorSummary::InvalidArgument, ErrorLevel::Permanent);
+        return ERR_OUT_OF_RANGE_KERNEL;
 
     s32 previous_count = available_count;
     available_count += release_count;
diff --git a/src/core/hle/kernel/shared_memory.cpp b/src/core/hle/kernel/shared_memory.cpp
index bc1560d12..922e5ab58 100644
--- a/src/core/hle/kernel/shared_memory.cpp
+++ b/src/core/hle/kernel/shared_memory.cpp
@@ -4,6 +4,7 @@
 
 #include <cstring>
 #include "common/logging/log.h"
+#include "core/hle/kernel/errors.h"
 #include "core/hle/kernel/memory.h"
 #include "core/hle/kernel/shared_memory.h"
 #include "core/memory.h"
@@ -102,24 +103,21 @@ ResultCode SharedMemory::Map(Process* target_process, VAddr address, MemoryPermi
 
     // Automatically allocated memory blocks can only be mapped with other_permissions = DontCare
     if (base_address == 0 && other_permissions != MemoryPermission::DontCare) {
-        return ResultCode(ErrorDescription::InvalidCombination, ErrorModule::OS,
-                          ErrorSummary::InvalidArgument, ErrorLevel::Usage);
+        return ERR_INVALID_COMBINATION;
     }
 
     // Error out if the requested permissions don't match what the creator process allows.
     if (static_cast<u32>(permissions) & ~static_cast<u32>(own_other_permissions)) {
         LOG_ERROR(Kernel, "cannot map id=%u, address=0x%08X name=%s, permissions don't match",
                   GetObjectId(), address, name.c_str());
-        return ResultCode(ErrorDescription::InvalidCombination, ErrorModule::OS,
-                          ErrorSummary::InvalidArgument, ErrorLevel::Usage);
+        return ERR_INVALID_COMBINATION;
     }
 
     // Heap-backed memory blocks can not be mapped with other_permissions = DontCare
     if (base_address != 0 && other_permissions == MemoryPermission::DontCare) {
         LOG_ERROR(Kernel, "cannot map id=%u, address=0x%08X name=%s, permissions don't match",
                   GetObjectId(), address, name.c_str());
-        return ResultCode(ErrorDescription::InvalidCombination, ErrorModule::OS,
-                          ErrorSummary::InvalidArgument, ErrorLevel::Usage);
+        return ERR_INVALID_COMBINATION;
     }
 
     // Error out if the provided permissions are not compatible with what the creator process needs.
@@ -127,8 +125,7 @@ ResultCode SharedMemory::Map(Process* target_process, VAddr address, MemoryPermi
         static_cast<u32>(this->permissions) & ~static_cast<u32>(other_permissions)) {
         LOG_ERROR(Kernel, "cannot map id=%u, address=0x%08X name=%s, permissions don't match",
                   GetObjectId(), address, name.c_str());
-        return ResultCode(ErrorDescription::WrongPermission, ErrorModule::OS,
-                          ErrorSummary::WrongArgument, ErrorLevel::Permanent);
+        return ERR_WRONG_PERMISSION;
     }
 
     // TODO(Subv): Check for the Shared Device Mem flag in the creator process.
@@ -144,8 +141,7 @@ ResultCode SharedMemory::Map(Process* target_process, VAddr address, MemoryPermi
         if (address < Memory::HEAP_VADDR || address + size >= Memory::SHARED_MEMORY_VADDR_END) {
             LOG_ERROR(Kernel, "cannot map id=%u, address=0x%08X name=%s, invalid address",
                       GetObjectId(), address, name.c_str());
-            return ResultCode(ErrorDescription::InvalidAddress, ErrorModule::OS,
-                              ErrorSummary::InvalidArgument, ErrorLevel::Usage);
+            return ERR_INVALID_ADDRESS;
         }
     }
 
diff --git a/src/core/hle/kernel/thread.cpp b/src/core/hle/kernel/thread.cpp
index 3b7555d87..519ff51a8 100644
--- a/src/core/hle/kernel/thread.cpp
+++ b/src/core/hle/kernel/thread.cpp
@@ -14,6 +14,7 @@
 #include "core/arm/skyeye_common/armstate.h"
 #include "core/core.h"
 #include "core/core_timing.h"
+#include "core/hle/kernel/errors.h"
 #include "core/hle/kernel/kernel.h"
 #include "core/hle/kernel/memory.h"
 #include "core/hle/kernel/mutex.h"
@@ -241,9 +242,7 @@ static void ThreadWakeupCallback(u64 thread_handle, int cycles_late) {
         for (auto& object : thread->wait_objects)
             object->RemoveWaitingThread(thread.get());
         thread->wait_objects.clear();
-        thread->SetWaitSynchronizationResult(ResultCode(ErrorDescription::Timeout, ErrorModule::OS,
-                                                        ErrorSummary::StatusChanged,
-                                                        ErrorLevel::Info));
+        thread->SetWaitSynchronizationResult(RESULT_TIMEOUT);
     }
 
     thread->ResumeFromWait();
@@ -351,10 +350,20 @@ static void ResetThreadContext(ARM_Interface::ThreadContext& context, u32 stack_
     context.cpsr = USER32MODE | ((entry_point & 1) << 5); // Usermode and THUMB mode
 }
 
-ResultVal<SharedPtr<Thread>> Thread::Create(std::string name, VAddr entry_point, s32 priority,
+ResultVal<SharedPtr<Thread>> Thread::Create(std::string name, VAddr entry_point, u32 priority,
                                             u32 arg, s32 processor_id, VAddr stack_top) {
-    ASSERT_MSG(priority >= THREADPRIO_HIGHEST && priority <= THREADPRIO_LOWEST,
-               "Invalid thread priority");
+    // Check if priority is in ranged. Lowest priority -> highest priority id.
+    if (priority > THREADPRIO_LOWEST) {
+        LOG_ERROR(Kernel_SVC, "Invalid thread priority: %d", priority);
+        return ERR_OUT_OF_RANGE;
+    }
+
+    if (processor_id > THREADPROCESSORID_MAX) {
+        LOG_ERROR(Kernel_SVC, "Invalid processor id: %d", processor_id);
+        return ERR_OUT_OF_RANGE_KERNEL;
+    }
+
+    // TODO(yuriks): Other checks, returning 0xD9001BEA
 
     if (!Memory::IsValidVirtualAddress(entry_point)) {
         LOG_ERROR(Kernel_SVC, "(name=%s): invalid entry %08x", name.c_str(), entry_point);
@@ -399,8 +408,7 @@ ResultVal<SharedPtr<Thread>> Thread::Create(std::string name, VAddr entry_point,
         if (linheap_memory->size() + Memory::PAGE_SIZE > memory_region->size) {
             LOG_ERROR(Kernel_SVC,
                       "Not enough space in region to allocate a new TLS page for thread");
-            return ResultCode(ErrorDescription::OutOfMemory, ErrorModule::Kernel,
-                              ErrorSummary::OutOfResource, ErrorLevel::Permanent);
+            return ERR_OUT_OF_MEMORY;
         }
 
         u32 offset = linheap_memory->size();
diff --git a/src/core/hle/kernel/thread.h b/src/core/hle/kernel/thread.h
index 6ab31c70b..7b5169cfc 100644
--- a/src/core/hle/kernel/thread.h
+++ b/src/core/hle/kernel/thread.h
@@ -57,7 +57,7 @@ public:
      * @param stack_top The address of the thread's stack top
      * @return A shared pointer to the newly created thread
      */
-    static ResultVal<SharedPtr<Thread>> Create(std::string name, VAddr entry_point, s32 priority,
+    static ResultVal<SharedPtr<Thread>> Create(std::string name, VAddr entry_point, u32 priority,
                                                u32 arg, s32 processor_id, VAddr stack_top);
 
     std::string GetName() const override {
diff --git a/src/core/hle/kernel/vm_manager.cpp b/src/core/hle/kernel/vm_manager.cpp
index 6dd24f846..cef1f7fa8 100644
--- a/src/core/hle/kernel/vm_manager.cpp
+++ b/src/core/hle/kernel/vm_manager.cpp
@@ -4,6 +4,7 @@
 
 #include <iterator>
 #include "common/assert.h"
+#include "core/hle/kernel/errors.h"
 #include "core/hle/kernel/vm_manager.h"
 #include "core/memory.h"
 #include "core/memory_setup.h"
diff --git a/src/core/hle/kernel/vm_manager.h b/src/core/hle/kernel/vm_manager.h
index 9055664b2..38e0d74d0 100644
--- a/src/core/hle/kernel/vm_manager.h
+++ b/src/core/hle/kernel/vm_manager.h
@@ -13,14 +13,6 @@
 
 namespace Kernel {
 
-const ResultCode ERR_INVALID_ADDRESS{// 0xE0E01BF5
-                                     ErrorDescription::InvalidAddress, ErrorModule::OS,
-                                     ErrorSummary::InvalidArgument, ErrorLevel::Usage};
-
-const ResultCode ERR_INVALID_ADDRESS_STATE{// 0xE0A01BF5
-                                           ErrorDescription::InvalidAddress, ErrorModule::OS,
-                                           ErrorSummary::InvalidState, ErrorLevel::Usage};
-
 enum class VMAType : u8 {
     /// VMA represents an unmapped region of the address space.
     Free,
diff --git a/src/core/hle/result.h b/src/core/hle/result.h
index 13b948871..c49650f7d 100644
--- a/src/core/hle/result.h
+++ b/src/core/hle/result.h
@@ -13,38 +13,15 @@
 
 // All the constants in this file come from http://3dbrew.org/wiki/Error_codes
 
-/// Detailed description of the error. This listing is likely incomplete.
+/**
+ * Detailed description of the error. Code 0 always means success. Codes 1000 and above are
+ * considered "well-known" and have common values between all modules. The meaning of other codes
+ * vary by module.
+ */
 enum class ErrorDescription : u32 {
     Success = 0,
-    SessionClosedByRemote = 26,
-    WrongPermission = 46,
-    OS_InvalidBufferDescriptor = 48,
-    MaxConnectionsReached = 52,
-    WrongAddress = 53,
-    FS_RomFSNotFound = 100,
-    FS_ArchiveNotMounted = 101,
-    FS_FileNotFound = 112,
-    FS_PathNotFound = 113,
-    FS_GameCardNotInserted = 141,
-    FS_NotFound = 120,
-    FS_FileAlreadyExists = 180,
-    FS_DirectoryAlreadyExists = 185,
-    FS_AlreadyExists = 190,
-    FS_InvalidOpenFlags = 230,
-    FS_DirectoryNotEmpty = 240,
-    FS_NotAFile = 250,
-    FS_NotFormatted = 340, ///< This is used by the FS service when creating a SaveData archive
-    OutofRangeOrMisalignedAddress =
-        513, // TODO(purpasmart): Check if this name fits its actual usage
-    GPU_FirstInitialization = 519,
-    FS_ExeFSSectionNotFound = 567,
-    FS_CommandNotAllowed = 630,
-    FS_InvalidReadFlag = 700,
-    FS_InvalidPath = 702,
-    FS_WriteBeyondEnd = 705,
-    FS_UnsupportedOpenFlags = 760,
-    FS_IncorrectExeFSReadSize = 761,
-    FS_UnexpectedFileOrDirectory = 770,
+
+    // Codes 1000 and above are considered "well-known" and have common values between all modules.
     InvalidSection = 1000,
     TooLarge = 1001,
     NotAuthorized = 1002,
@@ -218,7 +195,7 @@ enum class ErrorLevel : u32 {
 union ResultCode {
     u32 raw;
 
-    BitField<0, 10, ErrorDescription> description;
+    BitField<0, 10, u32> description;
     BitField<10, 8, ErrorModule> module;
 
     BitField<21, 6, ErrorSummary> summary;
@@ -228,45 +205,46 @@ union ResultCode {
     // error
     BitField<31, 1, u32> is_error;
 
-    explicit ResultCode(u32 raw) : raw(raw) {}
-    ResultCode(ErrorDescription description_, ErrorModule module_, ErrorSummary summary_,
-               ErrorLevel level_)
-        : raw(0) {
-        description.Assign(description_);
-        module.Assign(module_);
-        summary.Assign(summary_);
-        level.Assign(level_);
-    }
+    constexpr explicit ResultCode(u32 raw) : raw(raw) {}
+
+    constexpr ResultCode(ErrorDescription description, ErrorModule module, ErrorSummary summary,
+                         ErrorLevel level)
+        : ResultCode(static_cast<u32>(description), module, summary, level) {}
+
+    constexpr ResultCode(u32 description_, ErrorModule module_, ErrorSummary summary_,
+                         ErrorLevel level_)
+        : raw(description.FormatValue(description_) | module.FormatValue(module_) |
+              summary.FormatValue(summary_) | level.FormatValue(level_)) {}
 
-    ResultCode& operator=(const ResultCode& o) {
+    constexpr ResultCode& operator=(const ResultCode& o) {
         raw = o.raw;
         return *this;
     }
 
-    bool IsSuccess() const {
-        return is_error == 0;
+    constexpr bool IsSuccess() const {
+        return is_error.ExtractValue(raw) == 0;
     }
 
-    bool IsError() const {
-        return is_error == 1;
+    constexpr bool IsError() const {
+        return is_error.ExtractValue(raw) == 1;
     }
 };
 
-inline bool operator==(const ResultCode& a, const ResultCode& b) {
+constexpr bool operator==(const ResultCode& a, const ResultCode& b) {
     return a.raw == b.raw;
 }
 
-inline bool operator!=(const ResultCode& a, const ResultCode& b) {
+constexpr bool operator!=(const ResultCode& a, const ResultCode& b) {
     return a.raw != b.raw;
 }
 
 // Convenience functions for creating some common kinds of errors:
 
 /// The default success `ResultCode`.
-const ResultCode RESULT_SUCCESS(0);
+constexpr ResultCode RESULT_SUCCESS(0);
 
 /// Might be returned instead of a dummy success for unimplemented APIs.
-inline ResultCode UnimplementedFunction(ErrorModule module) {
+constexpr ResultCode UnimplementedFunction(ErrorModule module) {
     return ResultCode(ErrorDescription::NotImplemented, module, ErrorSummary::NotSupported,
                       ErrorLevel::Permanent);
 }
diff --git a/src/core/hle/service/boss/boss.cpp b/src/core/hle/service/boss/boss.cpp
index e0de037f8..91056189a 100644
--- a/src/core/hle/service/boss/boss.cpp
+++ b/src/core/hle/service/boss/boss.cpp
@@ -24,9 +24,7 @@ void InitializeSession(Service::Interface* self) {
 
     if (translation != IPC::CallingPidDesc()) {
         cmd_buff[0] = IPC::MakeHeader(0, 0x1, 0); // 0x40
-        cmd_buff[1] = ResultCode(ErrorDescription::OS_InvalidBufferDescriptor, ErrorModule::OS,
-                                 ErrorSummary::WrongArgument, ErrorLevel::Permanent)
-                          .raw;
+        cmd_buff[1] = IPC::ERR_INVALID_BUFFER_DESCRIPTOR.raw;
         LOG_ERROR(Service_BOSS, "The translation was invalid, translation=0x%08X", translation);
         return;
     }
diff --git a/src/core/hle/service/cfg/cfg.cpp b/src/core/hle/service/cfg/cfg.cpp
index 8c8c1ec77..caa41ded7 100644
--- a/src/core/hle/service/cfg/cfg.cpp
+++ b/src/core/hle/service/cfg/cfg.cpp
@@ -11,6 +11,7 @@
 #include "common/string_util.h"
 #include "common/swap.h"
 #include "core/file_sys/archive_systemsavedata.h"
+#include "core/file_sys/errors.h"
 #include "core/file_sys/file_backend.h"
 #include "core/hle/result.h"
 #include "core/hle/service/cfg/cfg.h"
@@ -411,7 +412,7 @@ ResultCode UpdateConfigNANDSavegame() {
 ResultCode FormatConfig() {
     ResultCode res = DeleteConfigNANDSaveFile();
     // The delete command fails if the file doesn't exist, so we have to check that too
-    if (!res.IsSuccess() && res.description != ErrorDescription::FS_FileNotFound) {
+    if (!res.IsSuccess() && res != FileSys::ERROR_FILE_NOT_FOUND) {
         return res;
     }
     // Delete the old data
@@ -534,7 +535,7 @@ ResultCode LoadConfigNANDSaveFile() {
         Service::FS::OpenArchive(Service::FS::ArchiveIdCode::SystemSaveData, archive_path);
 
     // If the archive didn't exist, create the files inside
-    if (archive_result.Code().description == ErrorDescription::FS_NotFormatted) {
+    if (archive_result.Code() == FileSys::ERR_NOT_FORMATTED) {
         // Format the archive to create the directories
         Service::FS::FormatArchive(Service::FS::ArchiveIdCode::SystemSaveData,
                                    FileSys::ArchiveFormatInfo(), archive_path);
diff --git a/src/core/hle/service/dsp_dsp.cpp b/src/core/hle/service/dsp_dsp.cpp
index 39711ea97..79171a0bc 100644
--- a/src/core/hle/service/dsp_dsp.cpp
+++ b/src/core/hle/service/dsp_dsp.cpp
@@ -289,9 +289,7 @@ static void WriteProcessPipe(Service::Interface* self) {
                                "size=0x%X, buffer=0x%08X",
                   cmd_buff[3], pipe_index, size, buffer);
         cmd_buff[0] = IPC::MakeHeader(0, 1, 0);
-        cmd_buff[1] = ResultCode(ErrorDescription::OS_InvalidBufferDescriptor, ErrorModule::OS,
-                                 ErrorSummary::WrongArgument, ErrorLevel::Permanent)
-                          .raw;
+        cmd_buff[1] = IPC::ERR_INVALID_BUFFER_DESCRIPTOR.raw;
         return;
     }
 
diff --git a/src/core/hle/service/fs/archive.cpp b/src/core/hle/service/fs/archive.cpp
index 6cddc1fdb..632712f2c 100644
--- a/src/core/hle/service/fs/archive.cpp
+++ b/src/core/hle/service/fs/archive.cpp
@@ -22,6 +22,7 @@
 #include "core/file_sys/archive_sdmcwriteonly.h"
 #include "core/file_sys/archive_systemsavedata.h"
 #include "core/file_sys/directory_backend.h"
+#include "core/file_sys/errors.h"
 #include "core/file_sys/file_backend.h"
 #include "core/hle/kernel/client_session.h"
 #include "core/hle/result.h"
@@ -50,16 +51,6 @@ static constexpr Kernel::Handle INVALID_HANDLE{};
 namespace Service {
 namespace FS {
 
-// TODO: Verify code
-/// Returned when a function is passed an invalid handle.
-const ResultCode ERR_INVALID_HANDLE(ErrorDescription::InvalidHandle, ErrorModule::FS,
-                                    ErrorSummary::InvalidArgument, ErrorLevel::Permanent);
-
-/// Returned when a function is passed an invalid archive handle.
-const ResultCode ERR_INVALID_ARCHIVE_HANDLE(ErrorDescription::FS_ArchiveNotMounted, ErrorModule::FS,
-                                            ErrorSummary::NotFound,
-                                            ErrorLevel::Status); // 0xC8804465
-
 // Command to access archive file
 enum class FileCommand : u32 {
     Dummy1 = 0x000100C6,
@@ -284,7 +275,7 @@ ResultVal<ArchiveHandle> OpenArchive(ArchiveIdCode id_code, FileSys::Path& archi
 
 ResultCode CloseArchive(ArchiveHandle handle) {
     if (handle_map.erase(handle) == 0)
-        return ERR_INVALID_ARCHIVE_HANDLE;
+        return FileSys::ERR_INVALID_ARCHIVE_HANDLE;
     else
         return RESULT_SUCCESS;
 }
@@ -309,7 +300,7 @@ ResultVal<std::shared_ptr<File>> OpenFileFromArchive(ArchiveHandle archive_handl
                                                      const FileSys::Mode mode) {
     ArchiveBackend* archive = GetArchive(archive_handle);
     if (archive == nullptr)
-        return ERR_INVALID_ARCHIVE_HANDLE;
+        return FileSys::ERR_INVALID_ARCHIVE_HANDLE;
 
     auto backend = archive->OpenFile(path, mode);
     if (backend.Failed())
@@ -322,7 +313,7 @@ ResultVal<std::shared_ptr<File>> OpenFileFromArchive(ArchiveHandle archive_handl
 ResultCode DeleteFileFromArchive(ArchiveHandle archive_handle, const FileSys::Path& path) {
     ArchiveBackend* archive = GetArchive(archive_handle);
     if (archive == nullptr)
-        return ERR_INVALID_ARCHIVE_HANDLE;
+        return FileSys::ERR_INVALID_ARCHIVE_HANDLE;
 
     return archive->DeleteFile(path);
 }
@@ -334,7 +325,7 @@ ResultCode RenameFileBetweenArchives(ArchiveHandle src_archive_handle,
     ArchiveBackend* src_archive = GetArchive(src_archive_handle);
     ArchiveBackend* dest_archive = GetArchive(dest_archive_handle);
     if (src_archive == nullptr || dest_archive == nullptr)
-        return ERR_INVALID_ARCHIVE_HANDLE;
+        return FileSys::ERR_INVALID_ARCHIVE_HANDLE;
 
     if (src_archive == dest_archive) {
         return src_archive->RenameFile(src_path, dest_path);
@@ -347,7 +338,7 @@ ResultCode RenameFileBetweenArchives(ArchiveHandle src_archive_handle,
 ResultCode DeleteDirectoryFromArchive(ArchiveHandle archive_handle, const FileSys::Path& path) {
     ArchiveBackend* archive = GetArchive(archive_handle);
     if (archive == nullptr)
-        return ERR_INVALID_ARCHIVE_HANDLE;
+        return FileSys::ERR_INVALID_ARCHIVE_HANDLE;
 
     return archive->DeleteDirectory(path);
 }
@@ -356,7 +347,7 @@ ResultCode DeleteDirectoryRecursivelyFromArchive(ArchiveHandle archive_handle,
                                                  const FileSys::Path& path) {
     ArchiveBackend* archive = GetArchive(archive_handle);
     if (archive == nullptr)
-        return ERR_INVALID_ARCHIVE_HANDLE;
+        return FileSys::ERR_INVALID_ARCHIVE_HANDLE;
 
     return archive->DeleteDirectoryRecursively(path);
 }
@@ -365,7 +356,7 @@ ResultCode CreateFileInArchive(ArchiveHandle archive_handle, const FileSys::Path
                                u64 file_size) {
     ArchiveBackend* archive = GetArchive(archive_handle);
     if (archive == nullptr)
-        return ERR_INVALID_ARCHIVE_HANDLE;
+        return FileSys::ERR_INVALID_ARCHIVE_HANDLE;
 
     return archive->CreateFile(path, file_size);
 }
@@ -373,7 +364,7 @@ ResultCode CreateFileInArchive(ArchiveHandle archive_handle, const FileSys::Path
 ResultCode CreateDirectoryFromArchive(ArchiveHandle archive_handle, const FileSys::Path& path) {
     ArchiveBackend* archive = GetArchive(archive_handle);
     if (archive == nullptr)
-        return ERR_INVALID_ARCHIVE_HANDLE;
+        return FileSys::ERR_INVALID_ARCHIVE_HANDLE;
 
     return archive->CreateDirectory(path);
 }
@@ -385,7 +376,7 @@ ResultCode RenameDirectoryBetweenArchives(ArchiveHandle src_archive_handle,
     ArchiveBackend* src_archive = GetArchive(src_archive_handle);
     ArchiveBackend* dest_archive = GetArchive(dest_archive_handle);
     if (src_archive == nullptr || dest_archive == nullptr)
-        return ERR_INVALID_ARCHIVE_HANDLE;
+        return FileSys::ERR_INVALID_ARCHIVE_HANDLE;
 
     if (src_archive == dest_archive) {
         return src_archive->RenameDirectory(src_path, dest_path);
@@ -399,7 +390,7 @@ ResultVal<std::shared_ptr<Directory>> OpenDirectoryFromArchive(ArchiveHandle arc
                                                                const FileSys::Path& path) {
     ArchiveBackend* archive = GetArchive(archive_handle);
     if (archive == nullptr)
-        return ERR_INVALID_ARCHIVE_HANDLE;
+        return FileSys::ERR_INVALID_ARCHIVE_HANDLE;
 
     auto backend = archive->OpenDirectory(path);
     if (backend.Failed())
@@ -412,7 +403,7 @@ ResultVal<std::shared_ptr<Directory>> OpenDirectoryFromArchive(ArchiveHandle arc
 ResultVal<u64> GetFreeBytesInArchive(ArchiveHandle archive_handle) {
     ArchiveBackend* archive = GetArchive(archive_handle);
     if (archive == nullptr)
-        return ERR_INVALID_ARCHIVE_HANDLE;
+        return FileSys::ERR_INVALID_ARCHIVE_HANDLE;
     return MakeResult<u64>(archive->GetFreeBytes());
 }
 
diff --git a/src/core/hle/service/fs/fs_user.cpp b/src/core/hle/service/fs/fs_user.cpp
index 33b290699..e53a970d3 100644
--- a/src/core/hle/service/fs/fs_user.cpp
+++ b/src/core/hle/service/fs/fs_user.cpp
@@ -8,6 +8,7 @@
 #include "common/logging/log.h"
 #include "common/scope_exit.h"
 #include "common/string_util.h"
+#include "core/file_sys/errors.h"
 #include "core/hle/kernel/client_session.h"
 #include "core/hle/result.h"
 #include "core/hle/service/fs/archive.h"
@@ -539,9 +540,7 @@ static void FormatSaveData(Service::Interface* self) {
     if (archive_id != FS::ArchiveIdCode::SaveData) {
         LOG_ERROR(Service_FS, "tried to format an archive different than SaveData, %u",
                   static_cast<u32>(archive_id));
-        cmd_buff[1] = ResultCode(ErrorDescription::FS_InvalidPath, ErrorModule::FS,
-                                 ErrorSummary::InvalidArgument, ErrorLevel::Usage)
-                          .raw;
+        cmd_buff[1] = FileSys::ERROR_INVALID_PATH.raw;
         return;
     }
 
@@ -802,9 +801,7 @@ static void InitializeWithSdkVersion(Service::Interface* self) {
         cmd_buff[1] = RESULT_SUCCESS.raw;
     } else {
         LOG_ERROR(Service_FS, "ProcessId Header must be 0x20");
-        cmd_buff[1] = ResultCode(ErrorDescription::OS_InvalidBufferDescriptor, ErrorModule::OS,
-                                 ErrorSummary::WrongArgument, ErrorLevel::Permanent)
-                          .raw;
+        cmd_buff[1] = IPC::ERR_INVALID_BUFFER_DESCRIPTOR.raw;
     }
 }
 
diff --git a/src/core/hle/service/gsp_gpu.cpp b/src/core/hle/service/gsp_gpu.cpp
index a960778a7..46c4ed01a 100644
--- a/src/core/hle/service/gsp_gpu.cpp
+++ b/src/core/hle/service/gsp_gpu.cpp
@@ -25,13 +25,24 @@ namespace GSP {
 // Beginning address of HW regs
 const u32 REGS_BEGIN = 0x1EB00000;
 
-const ResultCode ERR_GSP_REGS_OUTOFRANGE_OR_MISALIGNED(
-    ErrorDescription::OutofRangeOrMisalignedAddress, ErrorModule::GX, ErrorSummary::InvalidArgument,
-    ErrorLevel::Usage); // 0xE0E02A01
-const ResultCode ERR_GSP_REGS_MISALIGNED(ErrorDescription::MisalignedSize, ErrorModule::GX,
+namespace ErrCodes {
+enum {
+    // TODO(purpasmart): Check if this name fits its actual usage
+    OutofRangeOrMisalignedAddress = 513,
+    FirstInitialization = 519,
+};
+}
+
+constexpr ResultCode RESULT_FIRST_INITIALIZATION(ErrCodes::FirstInitialization, ErrorModule::GX,
+                                                 ErrorSummary::Success, ErrorLevel::Success);
+constexpr ResultCode ERR_REGS_OUTOFRANGE_OR_MISALIGNED(ErrCodes::OutofRangeOrMisalignedAddress,
+                                                       ErrorModule::GX,
+                                                       ErrorSummary::InvalidArgument,
+                                                       ErrorLevel::Usage); // 0xE0E02A01
+constexpr ResultCode ERR_REGS_MISALIGNED(ErrorDescription::MisalignedSize, ErrorModule::GX,
                                          ErrorSummary::InvalidArgument,
                                          ErrorLevel::Usage); // 0xE0E02BF2
-const ResultCode ERR_GSP_REGS_INVALID_SIZE(ErrorDescription::InvalidSize, ErrorModule::GX,
+constexpr ResultCode ERR_REGS_INVALID_SIZE(ErrorDescription::InvalidSize, ErrorModule::GX,
                                            ErrorSummary::InvalidArgument,
                                            ErrorLevel::Usage); // 0xE0E02BEC
 
@@ -93,11 +104,11 @@ static ResultCode WriteHWRegs(u32 base_address, u32 size_in_bytes, VAddr data_va
         LOG_ERROR(Service_GSP,
                   "Write address was out of range or misaligned! (address=0x%08x, size=0x%08x)",
                   base_address, size_in_bytes);
-        return ERR_GSP_REGS_OUTOFRANGE_OR_MISALIGNED;
+        return ERR_REGS_OUTOFRANGE_OR_MISALIGNED;
     } else if (size_in_bytes <= max_size_in_bytes) {
         if (size_in_bytes & 3) {
             LOG_ERROR(Service_GSP, "Misaligned size 0x%08x", size_in_bytes);
-            return ERR_GSP_REGS_MISALIGNED;
+            return ERR_REGS_MISALIGNED;
         } else {
             while (size_in_bytes > 0) {
                 WriteSingleHWReg(base_address, Memory::Read32(data_vaddr));
@@ -111,7 +122,7 @@ static ResultCode WriteHWRegs(u32 base_address, u32 size_in_bytes, VAddr data_va
 
     } else {
         LOG_ERROR(Service_GSP, "Out of range size 0x%08x", size_in_bytes);
-        return ERR_GSP_REGS_INVALID_SIZE;
+        return ERR_REGS_INVALID_SIZE;
     }
 }
 
@@ -134,11 +145,11 @@ static ResultCode WriteHWRegsWithMask(u32 base_address, u32 size_in_bytes, VAddr
         LOG_ERROR(Service_GSP,
                   "Write address was out of range or misaligned! (address=0x%08x, size=0x%08x)",
                   base_address, size_in_bytes);
-        return ERR_GSP_REGS_OUTOFRANGE_OR_MISALIGNED;
+        return ERR_REGS_OUTOFRANGE_OR_MISALIGNED;
     } else if (size_in_bytes <= max_size_in_bytes) {
         if (size_in_bytes & 3) {
             LOG_ERROR(Service_GSP, "Misaligned size 0x%08x", size_in_bytes);
-            return ERR_GSP_REGS_MISALIGNED;
+            return ERR_REGS_MISALIGNED;
         } else {
             while (size_in_bytes > 0) {
                 const u32 reg_address = base_address + REGS_BEGIN;
@@ -164,7 +175,7 @@ static ResultCode WriteHWRegsWithMask(u32 base_address, u32 size_in_bytes, VAddr
 
     } else {
         LOG_ERROR(Service_GSP, "Out of range size 0x%08x", size_in_bytes);
-        return ERR_GSP_REGS_INVALID_SIZE;
+        return ERR_REGS_INVALID_SIZE;
     }
 }
 
@@ -372,9 +383,7 @@ static void RegisterInterruptRelayQueue(Interface* self) {
     if (first_initialization) {
         // This specific code is required for a successful initialization, rather than 0
         first_initialization = false;
-        cmd_buff[1] = ResultCode(ErrorDescription::GPU_FirstInitialization, ErrorModule::GX,
-                                 ErrorSummary::Success, ErrorLevel::Success)
-                          .raw;
+        cmd_buff[1] = RESULT_FIRST_INITIALIZATION.raw;
     } else {
         cmd_buff[1] = RESULT_SUCCESS.raw;
     }
diff --git a/src/core/hle/service/ir/ir_user.cpp b/src/core/hle/service/ir/ir_user.cpp
index 226af0083..369115f09 100644
--- a/src/core/hle/service/ir/ir_user.cpp
+++ b/src/core/hle/service/ir/ir_user.cpp
@@ -267,8 +267,7 @@ static void InitializeIrNopShared(Interface* self) {
     shared_memory = Kernel::g_handle_table.Get<Kernel::SharedMemory>(handle);
     if (!shared_memory) {
         LOG_CRITICAL(Service_IR, "invalid shared memory handle 0x%08X", handle);
-        rb.Push(ResultCode(ErrorDescription::InvalidHandle, ErrorModule::OS,
-                           ErrorSummary::WrongArgument, ErrorLevel::Permanent));
+        rb.Push(IPC::ERR_INVALID_HANDLE);
         return;
     }
     shared_memory->name = "IR_USER: shared memory";
diff --git a/src/core/hle/service/ptm/ptm.cpp b/src/core/hle/service/ptm/ptm.cpp
index 319e8c946..39382ef09 100644
--- a/src/core/hle/service/ptm/ptm.cpp
+++ b/src/core/hle/service/ptm/ptm.cpp
@@ -3,6 +3,7 @@
 // Refer to the license.txt file included.
 
 #include "common/logging/log.h"
+#include "core/file_sys/errors.h"
 #include "core/file_sys/file_backend.h"
 #include "core/hle/service/fs/archive.h"
 #include "core/hle/service/ptm/ptm.h"
@@ -134,7 +135,7 @@ void Init() {
     auto archive_result =
         Service::FS::OpenArchive(Service::FS::ArchiveIdCode::SharedExtSaveData, archive_path);
     // If the archive didn't exist, create the files inside
-    if (archive_result.Code().description == ErrorDescription::FS_NotFormatted) {
+    if (archive_result.Code() == FileSys::ERR_NOT_FORMATTED) {
         // Format the archive to create the directories
         Service::FS::FormatArchive(Service::FS::ArchiveIdCode::SharedExtSaveData,
                                    FileSys::ArchiveFormatInfo(), archive_path);
diff --git a/src/core/hle/service/srv.cpp b/src/core/hle/service/srv.cpp
index 3bd787147..130c9d25e 100644
--- a/src/core/hle/service/srv.cpp
+++ b/src/core/hle/service/srv.cpp
@@ -30,9 +30,7 @@ static void RegisterClient(Interface* self) {
 
     if (cmd_buff[1] != IPC::CallingPidDesc()) {
         cmd_buff[0] = IPC::MakeHeader(0x0, 0x1, 0); // 0x40
-        cmd_buff[1] = ResultCode(ErrorDescription::OS_InvalidBufferDescriptor, ErrorModule::OS,
-                                 ErrorSummary::WrongArgument, ErrorLevel::Permanent)
-                          .raw;
+        cmd_buff[1] = IPC::ERR_INVALID_BUFFER_DESCRIPTOR.raw;
         return;
     }
     cmd_buff[0] = IPC::MakeHeader(0x1, 0x1, 0); // 0x10040
diff --git a/src/core/hle/svc.cpp b/src/core/hle/svc.cpp
index 8538cfc9d..30230d65a 100644
--- a/src/core/hle/svc.cpp
+++ b/src/core/hle/svc.cpp
@@ -14,6 +14,7 @@
 #include "core/hle/kernel/address_arbiter.h"
 #include "core/hle/kernel/client_port.h"
 #include "core/hle/kernel/client_session.h"
+#include "core/hle/kernel/errors.h"
 #include "core/hle/kernel/event.h"
 #include "core/hle/kernel/memory.h"
 #include "core/hle/kernel/mutex.h"
@@ -37,25 +38,6 @@ using Kernel::ERR_INVALID_HANDLE;
 
 namespace SVC {
 
-const ResultCode ERR_NOT_FOUND(ErrorDescription::NotFound, ErrorModule::Kernel,
-                               ErrorSummary::NotFound, ErrorLevel::Permanent); // 0xD88007FA
-const ResultCode ERR_PORT_NAME_TOO_LONG(ErrorDescription(30), ErrorModule::OS,
-                                        ErrorSummary::InvalidArgument,
-                                        ErrorLevel::Usage); // 0xE0E0181E
-
-const ResultCode ERR_SYNC_TIMEOUT(ErrorDescription::Timeout, ErrorModule::OS,
-                                  ErrorSummary::StatusChanged, ErrorLevel::Info);
-
-const ResultCode ERR_MISALIGNED_ADDRESS{// 0xE0E01BF1
-                                        ErrorDescription::MisalignedAddress, ErrorModule::OS,
-                                        ErrorSummary::InvalidArgument, ErrorLevel::Usage};
-const ResultCode ERR_MISALIGNED_SIZE{// 0xE0E01BF2
-                                     ErrorDescription::MisalignedSize, ErrorModule::OS,
-                                     ErrorSummary::InvalidArgument, ErrorLevel::Usage};
-const ResultCode ERR_INVALID_COMBINATION{// 0xE0E01BEE
-                                         ErrorDescription::InvalidCombination, ErrorModule::OS,
-                                         ErrorSummary::InvalidArgument, ErrorLevel::Usage};
-
 enum ControlMemoryOperation {
     MEMOP_FREE = 1,
     MEMOP_RESERVE = 2, // This operation seems to be unsupported in the kernel
@@ -195,8 +177,7 @@ static ResultCode MapMemoryBlock(Kernel::Handle handle, u32 addr, u32 permission
         LOG_ERROR(Kernel_SVC, "unknown permissions=0x%08X", permissions);
     }
 
-    return ResultCode(ErrorDescription::InvalidCombination, ErrorModule::OS,
-                      ErrorSummary::InvalidArgument, ErrorLevel::Usage);
+    return Kernel::ERR_INVALID_COMBINATION;
 }
 
 static ResultCode UnmapMemoryBlock(Kernel::Handle handle, u32 addr) {
@@ -216,16 +197,16 @@ static ResultCode UnmapMemoryBlock(Kernel::Handle handle, u32 addr) {
 /// Connect to an OS service given the port name, returns the handle to the port to out
 static ResultCode ConnectToPort(Kernel::Handle* out_handle, const char* port_name) {
     if (port_name == nullptr)
-        return ERR_NOT_FOUND;
+        return Kernel::ERR_NOT_FOUND;
     if (std::strlen(port_name) > 11)
-        return ERR_PORT_NAME_TOO_LONG;
+        return Kernel::ERR_PORT_NAME_TOO_LONG;
 
     LOG_TRACE(Kernel_SVC, "called port_name=%s", port_name);
 
     auto it = Service::g_kernel_named_ports.find(port_name);
     if (it == Service::g_kernel_named_ports.end()) {
         LOG_WARNING(Kernel_SVC, "tried to connect to unknown port: %s", port_name);
-        return ERR_NOT_FOUND;
+        return Kernel::ERR_NOT_FOUND;
     }
 
     auto client_port = it->second;
@@ -275,7 +256,7 @@ static ResultCode WaitSynchronization1(Kernel::Handle handle, s64 nano_seconds)
     if (object->ShouldWait(thread)) {
 
         if (nano_seconds == 0)
-            return ERR_SYNC_TIMEOUT;
+            return Kernel::RESULT_TIMEOUT;
 
         thread->wait_objects = {object};
         object->AddWaitingThread(thread);
@@ -289,7 +270,7 @@ static ResultCode WaitSynchronization1(Kernel::Handle handle, s64 nano_seconds)
         // Note: The output of this SVC will be set to RESULT_SUCCESS if the thread
         // resumes due to a signal in its wait objects.
         // Otherwise we retain the default value of timeout.
-        return ERR_SYNC_TIMEOUT;
+        return Kernel::RESULT_TIMEOUT;
     }
 
     object->Acquire(thread);
@@ -304,8 +285,7 @@ static ResultCode WaitSynchronizationN(s32* out, Kernel::Handle* handles, s32 ha
 
     // Check if 'handles' is invalid
     if (handles == nullptr)
-        return ResultCode(ErrorDescription::InvalidPointer, ErrorModule::Kernel,
-                          ErrorSummary::InvalidArgument, ErrorLevel::Permanent);
+        return Kernel::ERR_INVALID_POINTER;
 
     // NOTE: on real hardware, there is no nullptr check for 'out' (tested with firmware 4.4). If
     // this happens, the running application will crash.
@@ -313,8 +293,7 @@ static ResultCode WaitSynchronizationN(s32* out, Kernel::Handle* handles, s32 ha
 
     // Check if 'handle_count' is invalid
     if (handle_count < 0)
-        return ResultCode(ErrorDescription::OutOfRange, ErrorModule::OS,
-                          ErrorSummary::InvalidArgument, ErrorLevel::Usage);
+        return Kernel::ERR_OUT_OF_RANGE;
 
     using ObjectPtr = Kernel::SharedPtr<Kernel::WaitObject>;
     std::vector<ObjectPtr> objects(handle_count);
@@ -344,7 +323,7 @@ static ResultCode WaitSynchronizationN(s32* out, Kernel::Handle* handles, s32 ha
         // If a timeout value of 0 was provided, just return the Timeout error code instead of
         // suspending the thread.
         if (nano_seconds == 0)
-            return ERR_SYNC_TIMEOUT;
+            return Kernel::RESULT_TIMEOUT;
 
         // Put the thread to sleep
         thread->status = THREADSTATUS_WAIT_SYNCH_ALL;
@@ -365,7 +344,7 @@ static ResultCode WaitSynchronizationN(s32* out, Kernel::Handle* handles, s32 ha
         *out = -1;
         // Note: The output of this SVC will be set to RESULT_SUCCESS if the thread resumes due to
         // a signal in one of its wait objects.
-        return ERR_SYNC_TIMEOUT;
+        return Kernel::RESULT_TIMEOUT;
     } else {
         // Find the first object that is acquirable in the provided list of objects
         auto itr = std::find_if(objects.begin(), objects.end(), [thread](const ObjectPtr& object) {
@@ -385,7 +364,7 @@ static ResultCode WaitSynchronizationN(s32* out, Kernel::Handle* handles, s32 ha
         // If a timeout value of 0 was provided, just return the Timeout error code instead of
         // suspending the thread.
         if (nano_seconds == 0)
-            return ERR_SYNC_TIMEOUT;
+            return Kernel::RESULT_TIMEOUT;
 
         // Put the thread to sleep
         thread->status = THREADSTATUS_WAIT_SYNCH_ANY;
@@ -411,7 +390,7 @@ static ResultCode WaitSynchronizationN(s32* out, Kernel::Handle* handles, s32 ha
         // Otherwise we retain the default value of timeout, and -1 in the out parameter
         thread->wait_set_output = true;
         *out = -1;
-        return ERR_SYNC_TIMEOUT;
+        return Kernel::RESULT_TIMEOUT;
     }
 }
 
@@ -520,22 +499,20 @@ static ResultCode GetResourceLimitLimitValues(s64* values, Kernel::Handle resour
 }
 
 /// Creates a new thread
-static ResultCode CreateThread(Kernel::Handle* out_handle, s32 priority, u32 entry_point, u32 arg,
+static ResultCode CreateThread(Kernel::Handle* out_handle, u32 priority, u32 entry_point, u32 arg,
                                u32 stack_top, s32 processor_id) {
     using Kernel::Thread;
 
     std::string name = Common::StringFromFormat("unknown-%08" PRIX32, entry_point);
 
     if (priority > THREADPRIO_LOWEST) {
-        return ResultCode(ErrorDescription::OutOfRange, ErrorModule::OS,
-                          ErrorSummary::InvalidArgument, ErrorLevel::Usage);
+        return Kernel::ERR_OUT_OF_RANGE;
     }
 
     using Kernel::ResourceLimit;
     Kernel::SharedPtr<ResourceLimit>& resource_limit = Kernel::g_current_process->resource_limit;
     if (resource_limit->GetMaxResourceValue(Kernel::ResourceTypes::PRIORITY) > priority) {
-        return ResultCode(ErrorDescription::NotAuthorized, ErrorModule::OS,
-                          ErrorSummary::WrongArgument, ErrorLevel::Permanent);
+        return Kernel::ERR_NOT_AUTHORIZED;
     }
 
     switch (processor_id) {
@@ -605,8 +582,7 @@ static ResultCode GetThreadPriority(s32* priority, Kernel::Handle handle) {
 /// Sets the priority for the specified thread
 static ResultCode SetThreadPriority(Kernel::Handle handle, s32 priority) {
     if (priority > THREADPRIO_LOWEST) {
-        return ResultCode(ErrorDescription::OutOfRange, ErrorModule::OS,
-                          ErrorSummary::InvalidArgument, ErrorLevel::Usage);
+        return Kernel::ERR_OUT_OF_RANGE;
     }
 
     SharedPtr<Kernel::Thread> thread = Kernel::g_handle_table.Get<Kernel::Thread>(handle);
@@ -618,8 +594,7 @@ static ResultCode SetThreadPriority(Kernel::Handle handle, s32 priority) {
     // the one from the thread owner's resource limit.
     Kernel::SharedPtr<ResourceLimit>& resource_limit = Kernel::g_current_process->resource_limit;
     if (resource_limit->GetMaxResourceValue(Kernel::ResourceTypes::PRIORITY) > priority) {
-        return ResultCode(ErrorDescription::NotAuthorized, ErrorModule::OS,
-                          ErrorSummary::WrongArgument, ErrorLevel::Permanent);
+        return Kernel::ERR_NOT_AUTHORIZED;
     }
 
     thread->SetPriority(priority);
@@ -743,8 +718,7 @@ static ResultCode QueryProcessMemory(MemoryInfo* memory_info, PageInfo* page_inf
     auto vma = process->vm_manager.FindVMA(addr);
 
     if (vma == Kernel::g_current_process->vm_manager.vma_map.end())
-        return ResultCode(ErrorDescription::InvalidAddress, ErrorModule::OS,
-                          ErrorSummary::InvalidArgument, ErrorLevel::Usage);
+        return Kernel::ERR_INVALID_ADDRESS;
 
     memory_info->base_address = vma->second.base;
     memory_info->permission = static_cast<u32>(vma->second.permissions);
@@ -842,8 +816,7 @@ static ResultCode SetTimer(Kernel::Handle handle, s64 initial, s64 interval) {
     LOG_TRACE(Kernel_SVC, "called timer=0x%08X", handle);
 
     if (initial < 0 || interval < 0) {
-        return ResultCode(ErrorDescription::OutOfRange, ErrorModule::Kernel,
-                          ErrorSummary::InvalidArgument, ErrorLevel::Permanent);
+        return Kernel::ERR_OUT_OF_RANGE_KERNEL;
     }
 
     SharedPtr<Timer> timer = Kernel::g_handle_table.Get<Timer>(handle);
@@ -902,8 +875,7 @@ static ResultCode CreateMemoryBlock(Kernel::Handle* out_handle, u32 addr, u32 si
     using Kernel::SharedMemory;
 
     if (size % Memory::PAGE_SIZE != 0)
-        return ResultCode(ErrorDescription::MisalignedSize, ErrorModule::OS,
-                          ErrorSummary::InvalidArgument, ErrorLevel::Usage);
+        return Kernel::ERR_MISALIGNED_SIZE;
 
     SharedPtr<SharedMemory> shared_memory = nullptr;
 
@@ -924,16 +896,14 @@ static ResultCode CreateMemoryBlock(Kernel::Handle* out_handle, u32 addr, u32 si
 
     if (!VerifyPermissions(static_cast<MemoryPermission>(my_permission)) ||
         !VerifyPermissions(static_cast<MemoryPermission>(other_permission)))
-        return ResultCode(ErrorDescription::InvalidCombination, ErrorModule::OS,
-                          ErrorSummary::InvalidArgument, ErrorLevel::Usage);
+        return Kernel::ERR_INVALID_COMBINATION;
 
     // TODO(Subv): Processes with memory type APPLICATION are not allowed
     // to create memory blocks with addr = 0, any attempts to do so
     // should return error 0xD92007EA.
     if ((addr < Memory::PROCESS_IMAGE_VADDR || addr + size > Memory::SHARED_MEMORY_VADDR_END) &&
         addr != 0) {
-        return ResultCode(ErrorDescription::InvalidAddress, ErrorModule::OS,
-                          ErrorSummary::InvalidArgument, ErrorLevel::Usage);
+        return Kernel::ERR_INVALID_ADDRESS;
     }
 
     // When trying to create a memory block with address = 0,
@@ -1035,7 +1005,7 @@ static ResultCode GetProcessInfo(s64* out, Kernel::Handle process_handle, u32 ty
         *out = process->heap_used + process->linear_heap_used + process->misc_memory_used;
         if (*out % Memory::PAGE_SIZE != 0) {
             LOG_ERROR(Kernel_SVC, "called, memory size not page-aligned");
-            return ERR_MISALIGNED_SIZE;
+            return Kernel::ERR_MISALIGNED_SIZE;
         }
         break;
     case 1:
@@ -1051,19 +1021,15 @@ static ResultCode GetProcessInfo(s64* out, Kernel::Handle process_handle, u32 ty
     case 20:
         *out = Memory::FCRAM_PADDR - process->GetLinearHeapBase();
         break;
+    case 21:
+    case 22:
+    case 23:
+        // These return a different error value than higher invalid values
+        LOG_ERROR(Kernel_SVC, "unknown GetProcessInfo type=%u", type);
+        return Kernel::ERR_NOT_IMPLEMENTED;
     default:
         LOG_ERROR(Kernel_SVC, "unknown GetProcessInfo type=%u", type);
-
-        if (type >= 21 && type <= 23) {
-            return ResultCode( // 0xE0E01BF4
-                ErrorDescription::NotImplemented, ErrorModule::OS, ErrorSummary::InvalidArgument,
-                ErrorLevel::Usage);
-        } else {
-            return ResultCode( // 0xD8E007ED
-                ErrorDescription::InvalidEnumValue, ErrorModule::Kernel,
-                ErrorSummary::InvalidArgument, ErrorLevel::Permanent);
-        }
-        break;
+        return Kernel::ERR_INVALID_ENUM_VALUE;
     }
 
     return RESULT_SUCCESS;