diff --git a/Source/Core/Core/IOS/DI/DI.cpp b/Source/Core/Core/IOS/DI/DI.cpp
index 6810943699..4c15a71007 100644
--- a/Source/Core/Core/IOS/DI/DI.cpp
+++ b/Source/Core/Core/IOS/DI/DI.cpp
@@ -109,7 +109,7 @@ void DIDevice::ProcessQueuedIOCtl()
   auto finished = StartIOCtl(request);
   if (finished)
   {
-    CoreTiming::ScheduleEvent(2700 * SystemTimers::TIMER_RATIO, s_finish_executing_di_command,
+    CoreTiming::ScheduleEvent(IPC_OVERHEAD_TICKS, s_finish_executing_di_command,
                               static_cast<u64>(finished.value()));
     return;
   }
diff --git a/Source/Core/Core/IOS/ES/ES.cpp b/Source/Core/Core/IOS/ES/ES.cpp
index 8be562c84b..5ce32591c8 100644
--- a/Source/Core/Core/IOS/ES/ES.cpp
+++ b/Source/Core/Core/IOS/ES/ES.cpp
@@ -161,7 +161,7 @@ IPCReply ESDevice::GetTitleId(const IOCtlVRequest& request)
 
 static bool UpdateUIDAndGID(Kernel& kernel, const ES::TMDReader& tmd)
 {
-  ES::UIDSys uid_sys{kernel.GetFS()};
+  ES::UIDSys uid_sys{kernel.GetFSDevice()};
   const u64 title_id = tmd.GetTitleId();
   const u32 uid = uid_sys.GetOrInsertUIDForTitle(title_id);
   if (uid == 0)
@@ -177,7 +177,7 @@ static bool UpdateUIDAndGID(Kernel& kernel, const ES::TMDReader& tmd)
 static ReturnCode CheckIsAllowedToSetUID(Kernel& kernel, const u32 caller_uid,
                                          const ES::TMDReader& active_tmd)
 {
-  ES::UIDSys uid_map{kernel.GetFS()};
+  ES::UIDSys uid_map{kernel.GetFSDevice()};
   const u32 system_menu_uid = uid_map.GetOrInsertUIDForTitle(Titles::SYSTEM_MENU);
   if (!system_menu_uid)
     return ES_SHORT_READ;
diff --git a/Source/Core/Core/IOS/ES/ES.h b/Source/Core/Core/IOS/ES/ES.h
index c4636cab17..989474749d 100644
--- a/Source/Core/Core/IOS/ES/ES.h
+++ b/Source/Core/Core/IOS/ES/ES.h
@@ -87,8 +87,8 @@ public:
     No = false,
   };
 
-  ES::TMDReader FindImportTMD(u64 title_id) const;
-  ES::TMDReader FindInstalledTMD(u64 title_id) const;
+  ES::TMDReader FindImportTMD(u64 title_id, Ticks ticks = {}) const;
+  ES::TMDReader FindInstalledTMD(u64 title_id, Ticks ticks = {}) const;
   ES::TicketReader FindSignedTicket(u64 title_id) const;
 
   // Get installed titles (in /title) without checking for TMDs at all.
@@ -105,10 +105,10 @@ public:
   std::vector<std::array<u8, 20>> GetSharedContents() const;
 
   // Title contents
-  s32 OpenContent(const ES::TMDReader& tmd, u16 content_index, u32 uid);
-  ReturnCode CloseContent(u32 cfd, u32 uid);
-  s32 ReadContent(u32 cfd, u8* buffer, u32 size, u32 uid);
-  s32 SeekContent(u32 cfd, u32 offset, SeekMode mode, u32 uid);
+  s32 OpenContent(const ES::TMDReader& tmd, u16 content_index, u32 uid, Ticks ticks = {});
+  s32 CloseContent(u32 cfd, u32 uid, Ticks ticks = {});
+  s32 ReadContent(u32 cfd, u8* buffer, u32 size, u32 uid, Ticks ticks = {});
+  s32 SeekContent(u32 cfd, u32 offset, SeekMode mode, u32 uid, Ticks ticks = {});
 
   // Title management
   enum class TicketImportType
@@ -364,14 +364,12 @@ private:
   void FinishStaleImport(u64 title_id);
   void FinishAllStaleImports();
 
-  std::string GetContentPath(u64 title_id, const ES::Content& content,
-                             const ES::SharedContentMap& map) const;
-  std::string GetContentPath(u64 title_id, const ES::Content& content) const;
+  std::string GetContentPath(u64 title_id, const ES::Content& content, Ticks ticks = {}) const;
 
   struct OpenedContent
   {
     bool m_opened = false;
-    FS::Fd m_fd;
+    u64 m_fd;
     u64 m_title_id = 0;
     ES::Content m_content;
     u32 m_uid = 0;
diff --git a/Source/Core/Core/IOS/ES/Formats.cpp b/Source/Core/Core/IOS/ES/Formats.cpp
index fcda458126..441747a7d9 100644
--- a/Source/Core/Core/IOS/ES/Formats.cpp
+++ b/Source/Core/Core/IOS/ES/Formats.cpp
@@ -27,6 +27,7 @@
 #include "Core/CommonTitles.h"
 #include "Core/IOS/Device.h"
 #include "Core/IOS/FS/FileSystem.h"
+#include "Core/IOS/FS/FileSystemProxy.h"
 #include "Core/IOS/IOS.h"
 #include "Core/IOS/IOSC.h"
 #include "Core/IOS/Uids.h"
@@ -521,17 +522,21 @@ struct SharedContentMap::Entry
 };
 
 constexpr char CONTENT_MAP_PATH[] = "/shared1/content.map";
-SharedContentMap::SharedContentMap(std::shared_ptr<HLE::FS::FileSystem> fs) : m_fs{fs}
+SharedContentMap::SharedContentMap(std::shared_ptr<HLE::FSDevice> fs)
+    : m_fs_device{fs}, m_fs{fs->GetFS()}
 {
   static_assert(sizeof(Entry) == 28, "SharedContentMap::Entry has the wrong size");
 
   Entry entry;
-  const auto file = fs->OpenFile(PID_KERNEL, PID_KERNEL, CONTENT_MAP_PATH, HLE::FS::Mode::Read);
-  while (file && file->Read(&entry, 1))
+  s64 fd = fs->Open(PID_KERNEL, PID_KERNEL, CONTENT_MAP_PATH, HLE::FS::Mode::Read, {}, &m_ticks);
+  if (fd < 0)
+    return;
+  while (fs->Read(fd, &entry, 1, &m_ticks) == sizeof(entry))
   {
     m_entries.push_back(entry);
     m_last_id++;
   }
+  fs->Close(fd, &m_ticks);
 }
 
 SharedContentMap::~SharedContentMap() = default;
@@ -600,32 +605,34 @@ bool SharedContentMap::WriteEntries() const
          HLE::FS::ResultCode::Success;
 }
 
-static std::pair<u32, u64> ReadUidSysEntry(const HLE::FS::FileHandle& file)
+static std::pair<u32, u64> ReadUidSysEntry(HLE::FSDevice& fs, u64 fd, u64* ticks)
 {
   u64 title_id = 0;
-  if (!file.Read(&title_id, 1))
+  if (fs.Read(fd, &title_id, 1, ticks) != sizeof(title_id))
     return {};
 
   u32 uid = 0;
-  if (!file.Read(&uid, 1))
+  if (fs.Read(fd, &uid, 1, ticks) != sizeof(uid))
     return {};
 
   return {Common::swap32(uid), Common::swap64(title_id)};
 }
 
 constexpr char UID_MAP_PATH[] = "/sys/uid.sys";
-UIDSys::UIDSys(std::shared_ptr<HLE::FS::FileSystem> fs) : m_fs{fs}
+UIDSys::UIDSys(std::shared_ptr<HLE::FSDevice> fs) : m_fs_device{fs}, m_fs{fs->GetFS()}
 {
-  if (const auto file = fs->OpenFile(PID_KERNEL, PID_KERNEL, UID_MAP_PATH, HLE::FS::Mode::Read))
+  s64 fd = fs->Open(PID_KERNEL, PID_KERNEL, UID_MAP_PATH, HLE::FS::Mode::Read, {}, &m_ticks);
+  if (fd >= 0)
   {
     while (true)
     {
-      std::pair<u32, u64> entry = ReadUidSysEntry(*file);
+      std::pair<u32, u64> entry = ReadUidSysEntry(*fs, fd, &m_ticks);
       if (!entry.first && !entry.second)
         break;
 
       m_entries.insert(std::move(entry));
     }
+    fs->Close(fd, &m_ticks);
   }
 
   if (m_entries.empty())
diff --git a/Source/Core/Core/IOS/ES/Formats.h b/Source/Core/Core/IOS/ES/Formats.h
index 2ab6cfe6b4..1b1fe6996e 100644
--- a/Source/Core/Core/IOS/ES/Formats.h
+++ b/Source/Core/Core/IOS/ES/Formats.h
@@ -260,7 +260,7 @@ public:
 class SharedContentMap final
 {
 public:
-  explicit SharedContentMap(std::shared_ptr<HLE::FS::FileSystem> fs);
+  explicit SharedContentMap(std::shared_ptr<HLE::FSDevice> fs);
   ~SharedContentMap();
 
   std::optional<std::string> GetFilenameFromSHA1(const std::array<u8, 20>& sha1) const;
@@ -268,27 +268,35 @@ public:
   bool DeleteSharedContent(const std::array<u8, 20>& sha1);
   std::vector<std::array<u8, 20>> GetHashes() const;
 
+  u64 GetTicks() const { return m_ticks; }
+
 private:
   bool WriteEntries() const;
 
   struct Entry;
   u32 m_last_id = 0;
   std::vector<Entry> m_entries;
+  std::shared_ptr<HLE::FSDevice> m_fs_device;
   std::shared_ptr<HLE::FS::FileSystem> m_fs;
+  u64 m_ticks = 0;
 };
 
 class UIDSys final
 {
 public:
-  explicit UIDSys(std::shared_ptr<HLE::FS::FileSystem> fs);
+  explicit UIDSys(std::shared_ptr<HLE::FSDevice> fs);
 
   u32 GetUIDFromTitle(u64 title_id) const;
   u32 GetOrInsertUIDForTitle(u64 title_id);
   u32 GetNextUID() const;
 
+  u64 GetTicks() const { return m_ticks; }
+
 private:
+  std::shared_ptr<HLE::FSDevice> m_fs_device;
   std::shared_ptr<HLE::FS::FileSystem> m_fs;
   std::map<u32, u64> m_entries;
+  u64 m_ticks = 0;
 };
 
 class CertReader final : public SignedBlobReader
diff --git a/Source/Core/Core/IOS/ES/NandUtils.cpp b/Source/Core/Core/IOS/ES/NandUtils.cpp
index 44fb46f471..88cc040552 100644
--- a/Source/Core/Core/IOS/ES/NandUtils.cpp
+++ b/Source/Core/Core/IOS/ES/NandUtils.cpp
@@ -6,7 +6,6 @@
 #include <array>
 #include <cctype>
 #include <functional>
-#include <iterator>
 #include <string>
 #include <unordered_set>
 #include <vector>
@@ -17,35 +16,38 @@
 #include "Common/CommonTypes.h"
 #include "Common/Logging/Log.h"
 #include "Common/NandPaths.h"
+#include "Common/ScopeGuard.h"
 #include "Common/StringUtil.h"
 #include "Core/IOS/ES/ES.h"
 #include "Core/IOS/ES/Formats.h"
+#include "Core/IOS/FS/FileSystemProxy.h"
 #include "Core/IOS/Uids.h"
 
 namespace IOS::HLE
 {
-static ES::TMDReader FindTMD(FS::FileSystem* fs, u64 title_id, const std::string& tmd_path)
+static ES::TMDReader FindTMD(FSDevice& fs, const std::string& tmd_path, Ticks ticks)
 {
-  const auto file = fs->OpenFile(PID_KERNEL, PID_KERNEL, tmd_path, FS::Mode::Read);
-  if (!file)
+  const s64 fd = fs.Open(PID_KERNEL, PID_KERNEL, tmd_path, FS::Mode::Read, {}, ticks);
+  if (fd < 0)
     return {};
+  Common::ScopeGuard guard{[&] { fs.Close(fd, ticks); }};
 
-  std::vector<u8> tmd_bytes(file->GetStatus()->size);
-  if (!file->Read(tmd_bytes.data(), tmd_bytes.size()))
+  std::vector<u8> tmd_bytes(fs.GetFileStatus(fd, ticks)->size);
+  if (!fs.Read(fd, tmd_bytes.data(), tmd_bytes.size(), ticks))
     return {};
 
   return ES::TMDReader{std::move(tmd_bytes)};
 }
 
-ES::TMDReader ESDevice::FindImportTMD(u64 title_id) const
+ES::TMDReader ESDevice::FindImportTMD(u64 title_id, Ticks ticks) const
 {
-  return FindTMD(m_ios.GetFS().get(), title_id,
-                 Common::GetImportTitlePath(title_id) + "/content/title.tmd");
+  return FindTMD(*m_ios.GetFSDevice(), Common::GetImportTitlePath(title_id) + "/content/title.tmd",
+                 ticks);
 }
 
-ES::TMDReader ESDevice::FindInstalledTMD(u64 title_id) const
+ES::TMDReader ESDevice::FindInstalledTMD(u64 title_id, Ticks ticks) const
 {
-  return FindTMD(m_ios.GetFS().get(), title_id, Common::GetTMDFileName(title_id));
+  return FindTMD(*m_ios.GetFSDevice(), Common::GetTMDFileName(title_id), ticks);
 }
 
 ES::TicketReader ESDevice::FindSignedTicket(u64 title_id) const
@@ -171,16 +173,15 @@ ESDevice::GetStoredContentsFromTMD(const ES::TMDReader& tmd,
   if (!tmd.IsValid())
     return {};
 
-  const ES::SharedContentMap map{m_ios.GetFS()};
   const std::vector<ES::Content> contents = tmd.GetContents();
 
   std::vector<ES::Content> stored_contents;
 
   std::copy_if(contents.begin(), contents.end(), std::back_inserter(stored_contents),
-               [this, &tmd, &map, check_content_hashes](const ES::Content& content) {
+               [this, &tmd, check_content_hashes](const ES::Content& content) {
                  const auto fs = m_ios.GetFS();
 
-                 const std::string path = GetContentPath(tmd.GetTitleId(), content, map);
+                 const std::string path = GetContentPath(tmd.GetTitleId(), content);
                  if (path.empty())
                    return false;
 
@@ -217,7 +218,7 @@ u32 ESDevice::GetSharedContentsCount() const
 
 std::vector<std::array<u8, 20>> ESDevice::GetSharedContents() const
 {
-  const ES::SharedContentMap map{m_ios.GetFS()};
+  const ES::SharedContentMap map{m_ios.GetFSDevice()};
   return map.GetHashes();
 }
 
@@ -267,7 +268,7 @@ bool ESDevice::CreateTitleDirectories(u64 title_id, u16 group_id) const
     return false;
   }
 
-  ES::UIDSys uid_sys{fs};
+  ES::UIDSys uid_sys{m_ios.GetFSDevice()};
   const u32 uid = uid_sys.GetOrInsertUIDForTitle(title_id);
   if (fs->SetMetadata(0, data_dir, uid, group_id, 0, data_dir_modes) != FS::ResultCode::Success)
   {
@@ -382,16 +383,14 @@ void ESDevice::FinishAllStaleImports()
 }
 
 std::string ESDevice::GetContentPath(const u64 title_id, const ES::Content& content,
-                                     const ES::SharedContentMap& content_map) const
+                                     Ticks ticks) const
 {
   if (content.IsShared())
+  {
+    ES::SharedContentMap content_map{m_ios.GetFSDevice()};
+    ticks.Add(content_map.GetTicks());
     return content_map.GetFilenameFromSHA1(content.sha1).value_or("");
+  }
   return fmt::format("{}/{:08x}.app", Common::GetTitleContentPath(title_id), content.id);
 }
-
-std::string ESDevice::GetContentPath(const u64 title_id, const ES::Content& content) const
-{
-  ES::SharedContentMap map{m_ios.GetFS()};
-  return GetContentPath(title_id, content, map);
-}
 }  // namespace IOS::HLE
diff --git a/Source/Core/Core/IOS/ES/TitleContents.cpp b/Source/Core/Core/IOS/ES/TitleContents.cpp
index 0cab7b7c91..9a68475743 100644
--- a/Source/Core/Core/IOS/ES/TitleContents.cpp
+++ b/Source/Core/Core/IOS/ES/TitleContents.cpp
@@ -4,18 +4,17 @@
 
 #include "Core/IOS/ES/ES.h"
 
-#include <utility>
 #include <vector>
 
 #include "Common/Logging/Log.h"
-#include "Common/MsgHandler.h"
 #include "Core/HW/Memmap.h"
 #include "Core/IOS/ES/Formats.h"
+#include "Core/IOS/FS/FileSystemProxy.h"
 #include "Core/IOS/Uids.h"
 
 namespace IOS::HLE
 {
-s32 ESDevice::OpenContent(const ES::TMDReader& tmd, u16 content_index, u32 uid)
+s32 ESDevice::OpenContent(const ES::TMDReader& tmd, u16 content_index, u32 uid, Ticks ticks)
 {
   const u64 title_id = tmd.GetTitleId();
 
@@ -29,17 +28,19 @@ s32 ESDevice::OpenContent(const ES::TMDReader& tmd, u16 content_index, u32 uid)
     if (entry.m_opened)
       continue;
 
-    auto file = m_ios.GetFS()->OpenFile(PID_KERNEL, PID_KERNEL, GetContentPath(title_id, content),
-                                        FS::Mode::Read);
-    if (!file)
-      return FS::ConvertResult(file.Error());
+    const std::string path = GetContentPath(title_id, content, ticks);
+    s64 fd = m_ios.GetFSDevice()->Open(PID_KERNEL, PID_KERNEL, path, FS::Mode::Read, {}, ticks);
+    if (fd < 0)
+      return fd;
 
     entry.m_opened = true;
-    entry.m_fd = file->Release();
+    entry.m_fd = fd;
     entry.m_content = content;
     entry.m_title_id = title_id;
     entry.m_uid = uid;
-    INFO_LOG_FMT(IOS_ES, "OpenContent: title ID {:016x}, UID {:#x}, CFD {}", title_id, uid, i);
+    INFO_LOG_FMT(IOS_ES,
+                 "OpenContent: title ID {:016x}, UID {:#x}, content {:08x} (index {}) -> CFD {}",
+                 title_id, uid, content.id, content_index, i);
     return static_cast<s32>(i);
   }
 
@@ -48,43 +49,48 @@ s32 ESDevice::OpenContent(const ES::TMDReader& tmd, u16 content_index, u32 uid)
 
 IPCReply ESDevice::OpenContent(u32 uid, const IOCtlVRequest& request)
 {
-  if (!request.HasNumberOfValidVectors(3, 0) || request.in_vectors[0].size != sizeof(u64) ||
-      request.in_vectors[1].size != sizeof(ES::TicketView) ||
-      request.in_vectors[2].size != sizeof(u32))
-  {
-    return IPCReply(ES_EINVAL);
-  }
+  return MakeIPCReply(IPC_OVERHEAD_TICKS, [&](Ticks ticks) -> s32 {
+    if (!request.HasNumberOfValidVectors(3, 0) || request.in_vectors[0].size != sizeof(u64) ||
+        request.in_vectors[1].size != sizeof(ES::TicketView) ||
+        request.in_vectors[2].size != sizeof(u32))
+    {
+      return ES_EINVAL;
+    }
 
-  const u64 title_id = Memory::Read_U64(request.in_vectors[0].address);
-  const u32 content_index = Memory::Read_U32(request.in_vectors[2].address);
-  // TODO: check the ticket view, check permissions.
+    const u64 title_id = Memory::Read_U64(request.in_vectors[0].address);
+    const u32 content_index = Memory::Read_U32(request.in_vectors[2].address);
+    // TODO: check the ticket view, check permissions.
 
-  const auto tmd = FindInstalledTMD(title_id);
-  if (!tmd.IsValid())
-    return IPCReply(FS_ENOENT);
+    const auto tmd = FindInstalledTMD(title_id, ticks);
+    if (!tmd.IsValid())
+      return FS_ENOENT;
 
-  return IPCReply(OpenContent(tmd, content_index, uid));
+    return OpenContent(tmd, content_index, uid, ticks);
+  });
 }
 
 IPCReply ESDevice::OpenActiveTitleContent(u32 caller_uid, const IOCtlVRequest& request)
 {
-  if (!request.HasNumberOfValidVectors(1, 0) || request.in_vectors[0].size != sizeof(u32))
-    return IPCReply(ES_EINVAL);
+  return MakeIPCReply(IPC_OVERHEAD_TICKS, [&](Ticks ticks) -> s32 {
+    if (!request.HasNumberOfValidVectors(1, 0) || request.in_vectors[0].size != sizeof(u32))
+      return ES_EINVAL;
 
-  const u32 content_index = Memory::Read_U32(request.in_vectors[0].address);
+    const u32 content_index = Memory::Read_U32(request.in_vectors[0].address);
 
-  if (!m_title_context.active)
-    return IPCReply(ES_EINVAL);
+    if (!m_title_context.active)
+      return ES_EINVAL;
 
-  ES::UIDSys uid_map{m_ios.GetFS()};
-  const u32 uid = uid_map.GetOrInsertUIDForTitle(m_title_context.tmd.GetTitleId());
-  if (caller_uid != 0 && caller_uid != uid)
-    return IPCReply(ES_EACCES);
+    ES::UIDSys uid_map{m_ios.GetFSDevice()};
+    const u32 uid = uid_map.GetOrInsertUIDForTitle(m_title_context.tmd.GetTitleId());
+    ticks.Add(uid_map.GetTicks());
+    if (caller_uid != 0 && caller_uid != uid)
+      return ES_EACCES;
 
-  return IPCReply(OpenContent(m_title_context.tmd, content_index, caller_uid));
+    return OpenContent(m_title_context.tmd, content_index, caller_uid, ticks);
+  });
 }
 
-s32 ESDevice::ReadContent(u32 cfd, u8* buffer, u32 size, u32 uid)
+s32 ESDevice::ReadContent(u32 cfd, u8* buffer, u32 size, u32 uid, Ticks ticks)
 {
   if (cfd >= m_content_table.size())
     return ES_EINVAL;
@@ -95,23 +101,26 @@ s32 ESDevice::ReadContent(u32 cfd, u8* buffer, u32 size, u32 uid)
   if (!entry.m_opened)
     return IPC_EINVAL;
 
-  const auto result = m_ios.GetFS()->ReadBytesFromFile(entry.m_fd, buffer, size);
-  return result.Succeeded() ? *result : FS::ConvertResult(result.Error());
+  return m_ios.GetFSDevice()->Read(entry.m_fd, buffer, size, {}, ticks);
 }
 
 IPCReply ESDevice::ReadContent(u32 uid, const IOCtlVRequest& request)
 {
-  if (!request.HasNumberOfValidVectors(1, 1) || request.in_vectors[0].size != sizeof(u32))
-    return IPCReply(ES_EINVAL);
+  return MakeIPCReply(IPC_OVERHEAD_TICKS, [&](Ticks ticks) -> s32 {
+    if (!request.HasNumberOfValidVectors(1, 1) || request.in_vectors[0].size != sizeof(u32))
+      return ES_EINVAL;
 
-  const u32 cfd = Memory::Read_U32(request.in_vectors[0].address);
-  const u32 size = request.io_vectors[0].size;
-  const u32 addr = request.io_vectors[0].address;
+    const u32 cfd = Memory::Read_U32(request.in_vectors[0].address);
+    const u32 size = request.io_vectors[0].size;
+    const u32 addr = request.io_vectors[0].address;
 
-  return IPCReply(ReadContent(cfd, Memory::GetPointer(addr), size, uid));
+    INFO_LOG_FMT(IOS_ES, "ReadContent(uid={:#x}, cfd={}, size={}, addr={:08x})", uid, cfd, size,
+                 addr);
+    return ReadContent(cfd, Memory::GetPointer(addr), size, uid, ticks);
+  });
 }
 
-ReturnCode ESDevice::CloseContent(u32 cfd, u32 uid)
+s32 ESDevice::CloseContent(u32 cfd, u32 uid, Ticks ticks)
 {
   if (cfd >= m_content_table.size())
     return ES_EINVAL;
@@ -122,7 +131,7 @@ ReturnCode ESDevice::CloseContent(u32 cfd, u32 uid)
   if (!entry.m_opened)
     return IPC_EINVAL;
 
-  m_ios.GetFS()->Close(entry.m_fd);
+  m_ios.GetFSDevice()->Close(entry.m_fd, ticks);
   entry = {};
   INFO_LOG_FMT(IOS_ES, "CloseContent: CFD {}", cfd);
   return IPC_SUCCESS;
@@ -130,14 +139,16 @@ ReturnCode ESDevice::CloseContent(u32 cfd, u32 uid)
 
 IPCReply ESDevice::CloseContent(u32 uid, const IOCtlVRequest& request)
 {
-  if (!request.HasNumberOfValidVectors(1, 0) || request.in_vectors[0].size != sizeof(u32))
-    return IPCReply(ES_EINVAL);
+  return MakeIPCReply(IPC_OVERHEAD_TICKS, [&](Ticks ticks) -> s32 {
+    if (!request.HasNumberOfValidVectors(1, 0) || request.in_vectors[0].size != sizeof(u32))
+      return ES_EINVAL;
 
-  const u32 cfd = Memory::Read_U32(request.in_vectors[0].address);
-  return IPCReply(CloseContent(cfd, uid));
+    const u32 cfd = Memory::Read_U32(request.in_vectors[0].address);
+    return CloseContent(cfd, uid, ticks);
+  });
 }
 
-s32 ESDevice::SeekContent(u32 cfd, u32 offset, SeekMode mode, u32 uid)
+s32 ESDevice::SeekContent(u32 cfd, u32 offset, SeekMode mode, u32 uid, Ticks ticks)
 {
   if (cfd >= m_content_table.size())
     return ES_EINVAL;
@@ -148,19 +159,20 @@ s32 ESDevice::SeekContent(u32 cfd, u32 offset, SeekMode mode, u32 uid)
   if (!entry.m_opened)
     return IPC_EINVAL;
 
-  const auto result = m_ios.GetFS()->SeekFile(entry.m_fd, offset, static_cast<FS::SeekMode>(mode));
-  return result.Succeeded() ? *result : FS::ConvertResult(result.Error());
+  return m_ios.GetFSDevice()->Seek(entry.m_fd, offset, static_cast<FS::SeekMode>(mode), ticks);
 }
 
 IPCReply ESDevice::SeekContent(u32 uid, const IOCtlVRequest& request)
 {
-  if (!request.HasNumberOfValidVectors(3, 0))
-    return IPCReply(ES_EINVAL);
+  return MakeIPCReply(IPC_OVERHEAD_TICKS, [&](Ticks ticks) -> s32 {
+    if (!request.HasNumberOfValidVectors(3, 0))
+      return ES_EINVAL;
 
-  const u32 cfd = Memory::Read_U32(request.in_vectors[0].address);
-  const u32 offset = Memory::Read_U32(request.in_vectors[1].address);
-  const SeekMode mode = static_cast<SeekMode>(Memory::Read_U32(request.in_vectors[2].address));
+    const u32 cfd = Memory::Read_U32(request.in_vectors[0].address);
+    const u32 offset = Memory::Read_U32(request.in_vectors[1].address);
+    const auto mode = static_cast<SeekMode>(Memory::Read_U32(request.in_vectors[2].address));
 
-  return IPCReply(SeekContent(cfd, offset, mode, uid));
+    return SeekContent(cfd, offset, mode, uid, ticks);
+  });
 }
 }  // namespace IOS::HLE
diff --git a/Source/Core/Core/IOS/ES/TitleManagement.cpp b/Source/Core/Core/IOS/ES/TitleManagement.cpp
index 09b543f1db..cf63efd8f6 100644
--- a/Source/Core/Core/IOS/ES/TitleManagement.cpp
+++ b/Source/Core/Core/IOS/ES/TitleManagement.cpp
@@ -394,7 +394,7 @@ ReturnCode ESDevice::ImportContentEnd(Context& context, u32 content_fd)
   std::string content_path;
   if (content_info.IsShared())
   {
-    ES::SharedContentMap shared_content{fs};
+    ES::SharedContentMap shared_content{m_ios.GetFSDevice()};
     content_path = shared_content.AddSharedContent(content_info.sha1);
   }
   else
@@ -441,7 +441,7 @@ static bool HasAllRequiredContents(Kernel& ios, const ES::TMDReader& tmd)
 {
   const u64 title_id = tmd.GetTitleId();
   const std::vector<ES::Content> contents = tmd.GetContents();
-  const ES::SharedContentMap shared_content_map{ios.GetFS()};
+  const ES::SharedContentMap shared_content_map{ios.GetFSDevice()};
   return std::all_of(contents.cbegin(), contents.cend(), [&](const ES::Content& content) {
     if (content.IsOptional())
       return true;
@@ -793,7 +793,7 @@ ReturnCode ESDevice::ExportContentEnd(Context& context, u32 content_fd)
 {
   if (!context.title_import_export.valid || !context.title_import_export.content.valid)
     return ES_EINVAL;
-  return CloseContent(content_fd, 0);
+  return static_cast<ReturnCode>(CloseContent(content_fd, 0));
 }
 
 IPCReply ESDevice::ExportContentEnd(Context& context, const IOCtlVRequest& request)
@@ -818,7 +818,7 @@ IPCReply ESDevice::ExportTitleDone(Context& context, const IOCtlVRequest& reques
 
 ReturnCode ESDevice::DeleteSharedContent(const std::array<u8, 20>& sha1) const
 {
-  ES::SharedContentMap map{m_ios.GetFS()};
+  ES::SharedContentMap map{m_ios.GetFSDevice()};
   const auto content_path = map.GetFilenameFromSHA1(sha1);
   if (!content_path)
     return ES_EINVAL;
diff --git a/Source/Core/Core/IOS/FS/FileSystemProxy.cpp b/Source/Core/Core/IOS/FS/FileSystemProxy.cpp
index bb4e76a341..47197164d2 100644
--- a/Source/Core/Core/IOS/FS/FileSystemProxy.cpp
+++ b/Source/Core/Core/IOS/FS/FileSystemProxy.cpp
@@ -24,8 +24,7 @@ using namespace IOS::HLE::FS;
 
 static IPCReply GetFSReply(s32 return_value, u64 extra_tb_ticks = 0)
 {
-  // According to hardware tests, FS takes at least 2700 TB ticks to reply to commands.
-  return IPCReply{return_value, (2700 + extra_tb_ticks) * SystemTimers::TIMER_RATIO};
+  return IPCReply{return_value, IPC_OVERHEAD_TICKS + extra_tb_ticks * SystemTimers::TIMER_RATIO};
 }
 
 /// Duration of a superblock write (in timebase ticks).
@@ -95,10 +94,11 @@ FSDevice::FSDevice(Kernel& ios, const std::string& device_name) : Device(ios, de
 
 void FSDevice::DoState(PointerWrap& p)
 {
-  p.Do(m_fd_map);
-  p.Do(m_cache_fd);
-  p.Do(m_cache_chain_index);
   p.Do(m_dirty_cache);
+  p.Do(m_cache_chain_index);
+  p.Do(m_cache_fd);
+  p.Do(m_next_fd);
+  p.Do(m_fd_map);
 }
 
 template <typename... Args>
@@ -153,59 +153,78 @@ static IPCReply GetReplyForSuperblockOperation(int ios_version, ResultCode resul
 
 std::optional<IPCReply> FSDevice::Open(const OpenRequest& request)
 {
+  return MakeIPCReply([&](Ticks t) {
+    return Open(request.uid, request.gid, request.path, static_cast<Mode>(request.flags & 3),
+                request.fd, t);
+  });
+}
+
+s64 FSDevice::Open(FS::Uid uid, FS::Gid gid, const std::string& path, FS::Mode mode,
+                   std::optional<u32> ipc_fd, Ticks ticks)
+{
+  ticks.AddTimeBaseTicks(IPC_OVERHEAD_TICKS);
+
   if (m_fd_map.size() >= 16)
-    return GetFSReply(ConvertResult(ResultCode::NoFreeHandle));
+    return ConvertResult(ResultCode::NoFreeHandle);
 
-  if (request.path.size() >= 64)
-    return GetFSReply(ConvertResult(ResultCode::Invalid));
+  if (path.size() >= 64)
+    return ConvertResult(ResultCode::Invalid);
 
-  if (request.path == "/dev/fs")
+  const u64 fd = ipc_fd.has_value() ? u64(*ipc_fd) : m_next_fd++;
+
+  if (path == "/dev/fs")
   {
-    m_fd_map[request.fd] = {request.gid, request.uid, INVALID_FD};
-    return GetFSReply(IPC_SUCCESS);
+    m_fd_map[fd] = {gid, uid, INVALID_FD};
+    return fd;
   }
 
-  const u64 ticks = EstimateFileLookupTicks(request.path, FileLookupMode::Normal);
+  ticks.AddTimeBaseTicks(EstimateFileLookupTicks(path, FileLookupMode::Normal));
 
-  auto backend_fd = m_ios.GetFS()->OpenFile(request.uid, request.gid, request.path,
-                                            static_cast<Mode>(request.flags & 3));
-  LogResult(backend_fd, "OpenFile({})", request.path);
+  auto backend_fd = m_ios.GetFS()->OpenFile(uid, gid, path, mode);
+  LogResult(backend_fd, "OpenFile({})", path);
   if (!backend_fd)
-    return GetFSReply(ConvertResult(backend_fd.Error()), ticks);
+    return ConvertResult(backend_fd.Error());
 
-  m_fd_map[request.fd] = {request.gid, request.uid, backend_fd->Release()};
-  std::strncpy(m_fd_map[request.fd].name.data(), request.path.c_str(), 64);
-  return GetFSReply(IPC_SUCCESS, ticks);
+  auto& handle = m_fd_map[fd] = {gid, uid, backend_fd->Release()};
+  std::strncpy(handle.name.data(), path.c_str(), handle.name.size());
+  return fd;
 }
 
 std::optional<IPCReply> FSDevice::Close(u32 fd)
 {
-  u64 ticks = 0;
-  if (m_fd_map[fd].fs_fd != INVALID_FD)
+  return MakeIPCReply([&](Ticks t) { return Close(static_cast<u64>(fd), t); });
+}
+
+s32 FSDevice::Close(u64 fd, Ticks ticks)
+{
+  ticks.AddTimeBaseTicks(IPC_OVERHEAD_TICKS);
+
+  const auto& handle = m_fd_map[fd];
+  if (handle.fs_fd != INVALID_FD)
   {
     if (fd == m_cache_fd)
     {
-      ticks += SimulateFlushFileCache();
-      m_cache_fd = INVALID_FD;
+      ticks.AddTimeBaseTicks(SimulateFlushFileCache());
+      m_cache_fd.reset();
     }
 
-    if (m_fd_map[fd].superblock_flush_needed)
-      ticks += GetSuperblockWriteTbTicks(m_ios.GetVersion());
+    if (handle.superblock_flush_needed)
+      ticks.AddTimeBaseTicks(GetSuperblockWriteTbTicks(m_ios.GetVersion()));
 
-    const ResultCode result = m_ios.GetFS()->Close(m_fd_map[fd].fs_fd);
-    LogResult(result, "Close({})", m_fd_map[fd].name.data());
+    const ResultCode result = m_ios.GetFS()->Close(handle.fs_fd);
+    LogResult(result, "Close({})", handle.name.data());
     m_fd_map.erase(fd);
     if (result != ResultCode::Success)
-      return GetFSReply(ConvertResult(result));
+      return ConvertResult(result);
   }
   else
   {
     m_fd_map.erase(fd);
   }
-  return GetFSReply(IPC_SUCCESS, ticks);
+  return IPC_SUCCESS;
 }
 
-u64 FSDevice::SimulatePopulateFileCache(u32 fd, u32 offset, u32 file_size)
+u64 FSDevice::SimulatePopulateFileCache(u64 fd, u32 offset, u32 file_size)
 {
   if (HasCacheForFile(fd, offset))
     return 0;
@@ -221,22 +240,23 @@ u64 FSDevice::SimulatePopulateFileCache(u32 fd, u32 offset, u32 file_size)
 
 u64 FSDevice::SimulateFlushFileCache()
 {
-  if (m_cache_fd == INVALID_FD || !m_dirty_cache)
+  if (!m_cache_fd.has_value() || !m_dirty_cache)
     return 0;
   m_dirty_cache = false;
-  m_fd_map[m_cache_fd].superblock_flush_needed = true;
+  m_fd_map[*m_cache_fd].superblock_flush_needed = true;
   return GetClusterWriteTbTicks(m_ios.GetVersion());
 }
 
 // Simulate parts of the FS read/write logic to estimate ticks for file operations correctly.
-u64 FSDevice::EstimateTicksForReadWrite(const Handle& handle, const ReadWriteRequest& request)
+u64 FSDevice::EstimateTicksForReadWrite(const Handle& handle, u64 fd, IPCCommandType command,
+                                        u32 size)
 {
   u64 ticks = 0;
 
-  const bool is_write = request.command == IPC_CMD_WRITE;
+  const bool is_write = command == IPC_CMD_WRITE;
   const Result<FileStatus> status = m_ios.GetFS()->GetFileStatus(handle.fs_fd);
   u32 offset = status->offset;
-  u32 count = request.size;
+  u32 count = size;
   if (!is_write && count + offset > status->size)
     count = status->size - offset;
 
@@ -244,17 +264,17 @@ u64 FSDevice::EstimateTicksForReadWrite(const Handle& handle, const ReadWriteReq
   {
     u32 copy_length;
     // Fast path (if not cached): FS copies an entire cluster directly from/to the request.
-    if (!HasCacheForFile(request.fd, offset) && count >= CLUSTER_DATA_SIZE &&
+    if (!HasCacheForFile(fd, offset) && count >= CLUSTER_DATA_SIZE &&
         offset % CLUSTER_DATA_SIZE == 0)
     {
       ticks += (is_write ? GetClusterWriteTbTicks : GetClusterReadTbTicks)(m_ios.GetVersion());
       copy_length = CLUSTER_DATA_SIZE;
       if (is_write)
-        m_fd_map[request.fd].superblock_flush_needed = true;
+        m_fd_map[fd].superblock_flush_needed = true;
     }
     else
     {
-      ticks += SimulatePopulateFileCache(request.fd, offset, status->size);
+      ticks += SimulatePopulateFileCache(fd, offset, status->size);
 
       const u32 start = offset - m_cache_chain_index * CLUSTER_DATA_SIZE;
       copy_length = std::min<u32>(CLUSTER_DATA_SIZE - start, count);
@@ -276,7 +296,7 @@ u64 FSDevice::EstimateTicksForReadWrite(const Handle& handle, const ReadWriteReq
   return ticks;
 }
 
-bool FSDevice::HasCacheForFile(u32 fd, u32 offset) const
+bool FSDevice::HasCacheForFile(u64 fd, u32 offset) const
 {
   const u16 chain_index = static_cast<u16>(offset / CLUSTER_DATA_SIZE);
   return m_cache_fd == fd && m_cache_chain_index == chain_index;
@@ -284,52 +304,81 @@ bool FSDevice::HasCacheForFile(u32 fd, u32 offset) const
 
 std::optional<IPCReply> FSDevice::Read(const ReadWriteRequest& request)
 {
-  const Handle& handle = m_fd_map[request.fd];
+  return MakeIPCReply([&](Ticks t) {
+    return Read(request.fd, Memory::GetPointer(request.buffer), request.size, request.buffer, t);
+  });
+}
+
+s32 FSDevice::Read(u64 fd, u8* data, u32 size, std::optional<u32> ipc_buffer_addr, Ticks ticks)
+{
+  ticks.AddTimeBaseTicks(IPC_OVERHEAD_TICKS);
+
+  const Handle& handle = m_fd_map[fd];
   if (handle.fs_fd == INVALID_FD)
-    return GetFSReply(ConvertResult(ResultCode::Invalid));
+    return ConvertResult(ResultCode::Invalid);
 
   // Simulate the FS read logic to estimate ticks. Note: this must be done before reading.
-  const u64 ticks = EstimateTicksForReadWrite(handle, request);
+  ticks.AddTimeBaseTicks(EstimateTicksForReadWrite(handle, fd, IPC_CMD_READ, size));
+
+  const Result<u32> result = m_ios.GetFS()->ReadBytesFromFile(handle.fs_fd, data, size);
+  if (ipc_buffer_addr)
+    LogResult(result, "Read({}, 0x{:08x}, {})", handle.name.data(), *ipc_buffer_addr, size);
 
-  const Result<u32> result = m_ios.GetFS()->ReadBytesFromFile(
-      handle.fs_fd, Memory::GetPointer(request.buffer), request.size);
-  LogResult(result, "Read({}, 0x{:08x}, {})", handle.name.data(), request.buffer, request.size);
   if (!result)
-    return GetFSReply(ConvertResult(result.Error()));
+    return ConvertResult(result.Error());
 
-  return GetFSReply(*result, ticks);
+  return *result;
 }
 
 std::optional<IPCReply> FSDevice::Write(const ReadWriteRequest& request)
 {
-  const Handle& handle = m_fd_map[request.fd];
+  return MakeIPCReply([&](Ticks t) {
+    return Write(request.fd, Memory::GetPointer(request.buffer), request.size, request.buffer, t);
+  });
+}
+
+s32 FSDevice::Write(u64 fd, const u8* data, u32 size, std::optional<u32> ipc_buffer_addr,
+                    Ticks ticks)
+{
+  ticks.AddTimeBaseTicks(IPC_OVERHEAD_TICKS);
+
+  const Handle& handle = m_fd_map[fd];
   if (handle.fs_fd == INVALID_FD)
-    return GetFSReply(ConvertResult(ResultCode::Invalid));
+    return ConvertResult(ResultCode::Invalid);
 
   // Simulate the FS write logic to estimate ticks. Must be done before writing.
-  const u64 ticks = EstimateTicksForReadWrite(handle, request);
+  ticks.AddTimeBaseTicks(EstimateTicksForReadWrite(handle, fd, IPC_CMD_WRITE, size));
+
+  const Result<u32> result = m_ios.GetFS()->WriteBytesToFile(handle.fs_fd, data, size);
+  if (ipc_buffer_addr)
+    LogResult(result, "Write({}, 0x{:08x}, {})", handle.name.data(), *ipc_buffer_addr, size);
 
-  const Result<u32> result = m_ios.GetFS()->WriteBytesToFile(
-      handle.fs_fd, Memory::GetPointer(request.buffer), request.size);
-  LogResult(result, "Write({}, 0x{:08x}, {})", handle.name.data(), request.buffer, request.size);
   if (!result)
-    return GetFSReply(ConvertResult(result.Error()));
+    return ConvertResult(result.Error());
 
-  return GetFSReply(*result, ticks);
+  return *result;
 }
 
 std::optional<IPCReply> FSDevice::Seek(const SeekRequest& request)
 {
-  const Handle& handle = m_fd_map[request.fd];
-  if (handle.fs_fd == INVALID_FD)
-    return GetFSReply(ConvertResult(ResultCode::Invalid));
+  return MakeIPCReply([&](Ticks t) {
+    return Seek(request.fd, request.offset, HLE::FS::SeekMode(request.mode), t);
+  });
+}
 
-  const Result<u32> result =
-      m_ios.GetFS()->SeekFile(handle.fs_fd, request.offset, FS::SeekMode(request.mode));
-  LogResult(result, "Seek({}, 0x{:08x}, {})", handle.name.data(), request.offset, request.mode);
+s32 FSDevice::Seek(u64 fd, u32 offset, FS::SeekMode mode, Ticks ticks)
+{
+  ticks.AddTimeBaseTicks(IPC_OVERHEAD_TICKS);
+
+  const Handle& handle = m_fd_map[fd];
+  if (handle.fs_fd == INVALID_FD)
+    return ConvertResult(ResultCode::Invalid);
+
+  const Result<u32> result = m_ios.GetFS()->SeekFile(handle.fs_fd, offset, mode);
+  LogResult(result, "Seek({}, 0x{:08x}, {})", handle.name.data(), offset, mode);
   if (!result)
-    return GetFSReply(ConvertResult(result.Error()));
-  return GetFSReply(*result);
+    return ConvertResult(result.Error());
+  return *result;
 }
 
 #pragma pack(push, 1)
@@ -605,19 +654,32 @@ IPCReply FSDevice::SetFileVersionControl(const Handle& handle, const IOCtlReques
 
 IPCReply FSDevice::GetFileStats(const Handle& handle, const IOCtlRequest& request)
 {
-  if (request.buffer_out_size < 8 || handle.fs_fd == INVALID_FD)
+  if (request.buffer_out_size < 8)
     return GetFSReply(ConvertResult(ResultCode::Invalid));
 
-  const Result<FileStatus> status = m_ios.GetFS()->GetFileStatus(handle.fs_fd);
-  LogResult(status, "GetFileStatus({})", handle.name.data());
-  if (!status)
-    return IPCReply(ConvertResult(status.Error()));
+  return MakeIPCReply([&](Ticks ticks) {
+    const Result<FileStatus> status = GetFileStatus(request.fd, ticks);
+    if (!status)
+      return ConvertResult(status.Error());
 
-  ISFSFileStats out;
-  out.size = status->size;
-  out.seek_position = status->offset;
-  Memory::CopyToEmu(request.buffer_out, &out, sizeof(out));
-  return IPCReply(IPC_SUCCESS);
+    ISFSFileStats out;
+    out.size = status->size;
+    out.seek_position = status->offset;
+    Memory::CopyToEmu(request.buffer_out, &out, sizeof(out));
+    return IPC_SUCCESS;
+  });
+}
+
+FS::Result<FS::FileStatus> FSDevice::GetFileStatus(u64 fd, Ticks ticks)
+{
+  ticks.AddTimeBaseTicks(IPC_OVERHEAD_TICKS);
+  const auto& handle = m_fd_map[fd];
+  if (handle.fs_fd == INVALID_FD)
+    return ResultCode::Invalid;
+
+  auto status = m_ios.GetFS()->GetFileStatus(handle.fs_fd);
+  LogResult(status, "GetFileStatus({})", handle.name.data());
+  return status;
 }
 
 IPCReply FSDevice::GetUsage(const Handle& handle, const IOCtlVRequest& request)
diff --git a/Source/Core/Core/IOS/FS/FileSystemProxy.h b/Source/Core/Core/IOS/FS/FileSystemProxy.h
index e2967eb5dc..101dbdffc2 100644
--- a/Source/Core/Core/IOS/FS/FileSystemProxy.h
+++ b/Source/Core/Core/IOS/FS/FileSystemProxy.h
@@ -6,7 +6,9 @@
 
 #include <array>
 #include <map>
+#include <optional>
 #include <string>
+#include <utility>
 
 #include "Common/CommonTypes.h"
 #include "Core/IOS/Device.h"
@@ -24,6 +26,25 @@ class FSDevice : public Device
 public:
   FSDevice(Kernel& ios, const std::string& device_name);
 
+  // These are the equivalent of the IPC command handlers so IPC overhead is included
+  // in timing calculations.
+  s64 Open(FS::Uid uid, FS::Gid gid, const std::string& path, FS::Mode mode,
+           std::optional<u32> ipc_fd = {}, Ticks ticks = {});
+  s32 Close(u64 fd, Ticks ticks = {});
+  s32 Read(u64 fd, u8* data, u32 size, std::optional<u32> ipc_buffer_addr = {}, Ticks ticks = {});
+  s32 Write(u64 fd, const u8* data, u32 size, std::optional<u32> ipc_buffer_addr = {},
+            Ticks ticks = {});
+  s32 Seek(u64 fd, u32 offset, FS::SeekMode mode, Ticks ticks = {});
+  FS::Result<FS::FileStatus> GetFileStatus(u64 fd, Ticks ticks = {});
+
+  template <typename T>
+  s32 Read(u64 fd, T* data, size_t count, Ticks ticks = {})
+  {
+    return Read(fd, reinterpret_cast<u8*>(data), static_cast<u32>(sizeof(T) * count), {}, ticks);
+  }
+
+  std::shared_ptr<FS::FileSystem> GetFS() const { return m_ios.GetFS(); }
+
   void DoState(PointerWrap& p) override;
 
   std::optional<IPCReply> Open(const OpenRequest& request) override;
@@ -76,14 +97,16 @@ private:
   IPCReply GetUsage(const Handle& handle, const IOCtlVRequest& request);
   IPCReply Shutdown(const Handle& handle, const IOCtlRequest& request);
 
-  u64 EstimateTicksForReadWrite(const Handle& handle, const ReadWriteRequest& request);
-  u64 SimulatePopulateFileCache(u32 fd, u32 offset, u32 file_size);
+  u64 EstimateTicksForReadWrite(const Handle& handle, u64 fd, IPCCommandType command, u32 size);
+  u64 SimulatePopulateFileCache(u64 fd, u32 offset, u32 file_size);
   u64 SimulateFlushFileCache();
-  bool HasCacheForFile(u32 fd, u32 offset) const;
+  bool HasCacheForFile(u64 fd, u32 offset) const;
 
-  std::map<u32, Handle> m_fd_map;
-  u32 m_cache_fd = INVALID_FD;
-  u16 m_cache_chain_index = 0;
   bool m_dirty_cache = false;
+  u16 m_cache_chain_index = 0;
+  std::optional<u64> m_cache_fd;
+  // The first 0x18 IDs are reserved for the PPC.
+  u64 m_next_fd = 0x18;
+  std::map<u64, Handle> m_fd_map;
 };
 }  // namespace IOS::HLE
diff --git a/Source/Core/Core/IOS/IOS.cpp b/Source/Core/Core/IOS/IOS.cpp
index db0c3593f8..50b586e343 100644
--- a/Source/Core/Core/IOS/IOS.cpp
+++ b/Source/Core/Core/IOS/IOS.cpp
@@ -285,6 +285,11 @@ std::shared_ptr<FS::FileSystem> Kernel::GetFS()
   return m_fs;
 }
 
+std::shared_ptr<FSDevice> Kernel::GetFSDevice()
+{
+  return std::static_pointer_cast<FSDevice>(m_device_map.at("/dev/fs"));
+}
+
 std::shared_ptr<ESDevice> Kernel::GetES()
 {
   return std::static_pointer_cast<ESDevice>(m_device_map.at("/dev/es"));
diff --git a/Source/Core/Core/IOS/IOS.h b/Source/Core/Core/IOS/IOS.h
index ba823894b9..fe2336cd47 100644
--- a/Source/Core/Core/IOS/IOS.h
+++ b/Source/Core/Core/IOS/IOS.h
@@ -30,6 +30,7 @@ class FileSystem;
 
 class Device;
 class ESDevice;
+class FSDevice;
 
 struct Request;
 struct OpenRequest;
@@ -45,6 +46,40 @@ struct IPCReply
   u64 reply_delay_ticks;
 };
 
+constexpr u64 IPC_OVERHEAD_TICKS = 2700_tbticks;
+
+// Used to make it more convenient for functions to return timing information
+// without having to explicitly keep track of ticks in callers.
+class Ticks
+{
+public:
+  Ticks(u64* ticks = nullptr) : m_ticks(ticks) {}
+
+  void Add(u64 ticks)
+  {
+    if (m_ticks != nullptr)
+      *m_ticks += ticks;
+  }
+
+  void AddTimeBaseTicks(u64 tb_ticks) { Add(tb_ticks * SystemTimers::TIMER_RATIO); }
+
+private:
+  u64* m_ticks = nullptr;
+};
+
+template <typename ResultProducer>
+IPCReply MakeIPCReply(u64 ticks, const ResultProducer& fn)
+{
+  const s32 result_value = fn(Ticks{&ticks});
+  return IPCReply{result_value, ticks};
+}
+
+template <typename ResultProducer>
+IPCReply MakeIPCReply(const ResultProducer& fn)
+{
+  return MakeIPCReply(0, fn);
+}
+
 enum IPCCommandType : u32
 {
   IPC_CMD_OPEN = 1,
@@ -84,6 +119,7 @@ public:
   // These are *always* part of the IOS kernel and always available.
   // They are also the only available resource managers even before loading any module.
   std::shared_ptr<FS::FileSystem> GetFS();
+  std::shared_ptr<FSDevice> GetFSDevice();
   std::shared_ptr<ESDevice> GetES();
 
   void SDIO_EventNotify();
diff --git a/Source/Core/Core/State.cpp b/Source/Core/Core/State.cpp
index cca921c421..3d20c0fb05 100644
--- a/Source/Core/Core/State.cpp
+++ b/Source/Core/Core/State.cpp
@@ -74,7 +74,7 @@ static Common::Event g_compressAndDumpStateSyncEvent;
 static std::thread g_save_thread;
 
 // Don't forget to increase this after doing changes on the savestate system
-constexpr u32 STATE_VERSION = 128;  // Last changed in PR 9366
+constexpr u32 STATE_VERSION = 129;  // Last changed in PR 9511
 
 // Maps savestate versions to Dolphin versions.
 // Versions after 42 don't need to be added to this list,