DiscIO: Make all BlobReader implementations use DirectIOFile to make CopyReader functionality thread safe.

19 files changed, 166 insertions, 235 deletions

diff --git a/Source/Core/DiscIO/Blob.cpp b/Source/Core/DiscIO/Blob.cpp
index 9e1ddb9ead..aad8b60b5e 100644
--- a/Source/Core/DiscIO/Blob.cpp
+++ b/Source/Core/DiscIO/Blob.cpp
@@ -4,14 +4,13 @@
 #include "DiscIO/Blob.h"
 
 #include <algorithm>
-#include <cstddef>
-#include <limits>
 #include <memory>
 #include <string>
 #include <utility>
 
+#include "Common/BitUtils.h"
 #include "Common/CommonTypes.h"
-#include "Common/IOFile.h"
+#include "Common/DirectIOFile.h"
 #include "Common/MsgHandler.h"
 
 #include "DiscIO/CISOBlob.h"
@@ -213,9 +212,9 @@ u32 SectorReader::ReadChunk(u8* buffer, u64 chunk_num)
 
 std::unique_ptr<BlobReader> CreateBlobReader(const std::string& filename)
 {
-  File::IOFile file(filename, "rb");
+  File::DirectIOFile file(filename, File::AccessMode::Read);
   u32 magic;
-  if (!file.ReadArray(&magic, 1))
+  if (!file.Read(Common::AsWritableU8Span(magic)))
     return nullptr;
 
   // Conveniently, every supported file format (except for plain disc images and
diff --git a/Source/Core/DiscIO/CISOBlob.cpp b/Source/Core/DiscIO/CISOBlob.cpp
index 001c462694..df32cbaadc 100644
--- a/Source/Core/DiscIO/CISOBlob.cpp
+++ b/Source/Core/DiscIO/CISOBlob.cpp
@@ -4,22 +4,20 @@
 #include "DiscIO/CISOBlob.h"
 
 #include <algorithm>
-#include <cstdio>
 #include <memory>
 #include <utility>
 
+#include "Common/BitUtils.h"
 #include "Common/CommonTypes.h"
-#include "Common/IOFile.h"
 
 namespace DiscIO
 {
-CISOFileReader::CISOFileReader(File::IOFile file) : m_file(std::move(file))
+CISOFileReader::CISOFileReader(File::DirectIOFile file) : m_file(std::move(file))
 {
   m_size = m_file.GetSize();
 
   CISOHeader header;
-  m_file.Seek(0, File::SeekOrigin::Begin);
-  m_file.ReadArray(&header, 1);
+  m_file.OffsetRead(0, Common::AsWritableU8Span(header));
 
   m_block_size = header.block_size;
 
@@ -28,11 +26,10 @@ CISOFileReader::CISOFileReader(File::IOFile file) : m_file(std::move(file))
     m_ciso_map[idx] = (1 == header.map[idx]) ? count++ : UNUSED_BLOCK_ID;
 }
 
-std::unique_ptr<CISOFileReader> CISOFileReader::Create(File::IOFile file)
+std::unique_ptr<CISOFileReader> CISOFileReader::Create(File::DirectIOFile file)
 {
   CISOHeader header;
-  if (file.Seek(0, File::SeekOrigin::Begin) && file.ReadArray(&header, 1) &&
-      header.magic == CISO_MAGIC)
+  if (file.OffsetRead(0, Common::AsWritableU8Span(header)) && header.magic == CISO_MAGIC)
   {
     return std::unique_ptr<CISOFileReader>(new CISOFileReader(std::move(file)));
   }
@@ -42,7 +39,7 @@ std::unique_ptr<CISOFileReader> CISOFileReader::Create(File::IOFile file)
 
 std::unique_ptr<BlobReader> CISOFileReader::CopyReader() const
 {
-  return Create(m_file.Duplicate("rb"));
+  return Create(m_file);
 }
 
 u64 CISOFileReader::GetDataSize() const
@@ -71,12 +68,8 @@ bool CISOFileReader::Read(u64 offset, u64 nbytes, u8* out_ptr)
       // calculate the base address
       u64 const file_off = CISO_HEADER_SIZE + m_ciso_map[block] * (u64)m_block_size + data_offset;
 
-      if (!(m_file.Seek(file_off, File::SeekOrigin::Begin) &&
-            m_file.ReadArray(out_ptr, bytes_to_read)))
-      {
-        m_file.ClearError();
+      if (!m_file.OffsetRead(file_off, out_ptr, bytes_to_read))
         return false;
-      }
     }
     else
     {
diff --git a/Source/Core/DiscIO/CISOBlob.h b/Source/Core/DiscIO/CISOBlob.h
index c32c23bd35..1611e49ba9 100644
--- a/Source/Core/DiscIO/CISOBlob.h
+++ b/Source/Core/DiscIO/CISOBlob.h
@@ -3,12 +3,11 @@
 
 #pragma once
 
-#include <cstdio>
 #include <memory>
 #include <string>
 
 #include "Common/CommonTypes.h"
-#include "Common/IOFile.h"
+#include "Common/DirectIOFile.h"
 #include "DiscIO/Blob.h"
 
 namespace DiscIO
@@ -33,7 +32,7 @@ struct CISOHeader
 class CISOFileReader final : public BlobReader
 {
 public:
-  static std::unique_ptr<CISOFileReader> Create(File::IOFile file);
+  static std::unique_ptr<CISOFileReader> Create(File::DirectIOFile file);
 
   BlobType GetBlobType() const override { return BlobType::CISO; }
   std::unique_ptr<BlobReader> CopyReader() const override;
@@ -50,12 +49,12 @@ public:
   bool Read(u64 offset, u64 nbytes, u8* out_ptr) override;
 
 private:
-  CISOFileReader(File::IOFile file);
+  CISOFileReader(File::DirectIOFile file);
 
   typedef u16 MapType;
   static constexpr MapType UNUSED_BLOCK_ID = UINT16_MAX;
 
-  File::IOFile m_file;
+  File::DirectIOFile m_file;
   u64 m_size;
   u32 m_block_size;
   MapType m_ciso_map[CISO_MAP_SIZE];
diff --git a/Source/Core/DiscIO/CompressedBlob.cpp b/Source/Core/DiscIO/CompressedBlob.cpp
index 99a982efd9..7f86ee2388 100644
--- a/Source/Core/DiscIO/CompressedBlob.cpp
+++ b/Source/Core/DiscIO/CompressedBlob.cpp
@@ -4,7 +4,6 @@
 #include "DiscIO/CompressedBlob.h"
 
 #include <algorithm>
-#include <cstdio>
 #include <cstring>
 #include <memory>
 #include <string>
@@ -19,10 +18,10 @@
 #endif
 
 #include "Common/Assert.h"
+#include "Common/BitUtils.h"
 #include "Common/CommonTypes.h"
 #include "Common/FileUtil.h"
 #include "Common/Hash.h"
-#include "Common/IOFile.h"
 #include "Common/Logging/Log.h"
 #include "Common/MsgHandler.h"
 #include "DiscIO/Blob.h"
@@ -32,22 +31,23 @@
 
 namespace DiscIO
 {
-bool IsGCZBlob(File::IOFile& file);
+bool IsGCZBlob(File::DirectIOFile& file);
 
-CompressedBlobReader::CompressedBlobReader(File::IOFile file, const std::string& filename)
+CompressedBlobReader::CompressedBlobReader(File::DirectIOFile file, const std::string& filename)
     : m_file(std::move(file)), m_file_name(filename)
 {
   m_file_size = m_file.GetSize();
   m_file.Seek(0, File::SeekOrigin::Begin);
-  m_file.ReadArray(&m_header, 1);
+  m_file.Read(Common::AsWritableU8Span(m_header));
 
   SetSectorSize(m_header.block_size);
 
   // cache block pointers and hashes
   m_block_pointers.resize(m_header.num_blocks);
-  m_file.ReadArray(m_block_pointers.data(), m_header.num_blocks);
+  m_file.Read(Common::AsWritableU8Span(m_block_pointers));
+
   m_hashes.resize(m_header.num_blocks);
-  m_file.ReadArray(m_hashes.data(), m_header.num_blocks);
+  m_file.Read(Common::AsWritableU8Span(m_hashes));
 
   m_data_offset = (sizeof(CompressedBlobHeader)) +
                   (sizeof(u64)) * m_header.num_blocks     // skip block pointers
@@ -60,7 +60,7 @@ CompressedBlobReader::CompressedBlobReader(File::IOFile file, const std::string&
   m_zlib_buffer.resize(zlib_buffer_size);
 }
 
-std::unique_ptr<CompressedBlobReader> CompressedBlobReader::Create(File::IOFile file,
+std::unique_ptr<CompressedBlobReader> CompressedBlobReader::Create(File::DirectIOFile file,
                                                                    const std::string& filename)
 {
   if (IsGCZBlob(file))
@@ -74,7 +74,7 @@ CompressedBlobReader::~CompressedBlobReader() = default;
 
 std::unique_ptr<BlobReader> CompressedBlobReader::CopyReader() const
 {
-  return Create(m_file.Duplicate("rb"), m_file_name);
+  return Create(m_file, m_file_name);
 }
 
 // IMPORTANT: Calling this function invalidates all earlier pointers gotten from this function.
@@ -107,12 +107,10 @@ bool CompressedBlobReader::GetBlock(u64 block_num, u8* out_ptr)
   // clear unused part of zlib buffer. maybe this can be deleted when it works fully.
   memset(&m_zlib_buffer[comp_block_size], 0, m_zlib_buffer.size() - comp_block_size);
 
-  m_file.Seek(offset, File::SeekOrigin::Begin);
-  if (!m_file.ReadBytes(m_zlib_buffer.data(), comp_block_size))
+  if (!m_file.OffsetRead(offset, m_zlib_buffer.data(), comp_block_size))
   {
     ERROR_LOG_FMT(DISCIO, "The disc image \"{}\" is truncated, some of the data is missing.",
                   m_file_name);
-    m_file.ClearError();
     return false;
   }
 
@@ -241,7 +239,7 @@ static ConversionResult<OutputParameters> Compress(CompressThreadState* state,
   return std::move(output_parameters);
 }
 
-static ConversionResultCode Output(OutputParameters parameters, File::IOFile* outfile,
+static ConversionResultCode Output(OutputParameters parameters, File::DirectIOFile* outfile,
                                    u64* position, std::vector<u64>* offsets, int progress_monitor,
                                    u32 num_blocks, const CompressCB& callback)
 {
@@ -252,7 +250,7 @@ static ConversionResultCode Output(OutputParameters parameters, File::IOFile* ou
 
   *position += parameters.data.size();
 
-  if (!outfile->WriteBytes(parameters.data.data(), parameters.data.size()))
+  if (!outfile->Write(parameters.data))
     return ConversionResultCode::WriteFailed;
 
   if (parameters.block_number % progress_monitor == 0)
@@ -278,8 +276,8 @@ bool ConvertToGCZ(BlobReader* infile, const std::string& infile_path,
 {
   ASSERT(infile->GetDataSizeType() == DataSizeType::Accurate);
 
-  File::IOFile outfile(outfile_path, "wb");
-  if (!outfile)
+  File::DirectIOFile outfile(outfile_path, File::AccessMode::Write);
+  if (!outfile.IsOpen())
   {
     PanicAlertFmtT(
         "Failed to open the output file \"{0}\".\n"
@@ -365,9 +363,9 @@ bool ConvertToGCZ(BlobReader* infile, const std::string& infile_path,
   {
     // Okay, go back and fill in headers
     outfile.Seek(0, File::SeekOrigin::Begin);
-    outfile.WriteArray(&header, 1);
-    outfile.WriteArray(offsets.data(), header.num_blocks);
-    outfile.WriteArray(hashes.data(), header.num_blocks);
+    outfile.Write(Common::AsU8Span(header));
+    outfile.Write(Common::AsU8Span(offsets));
+    outfile.Write(Common::AsU8Span(hashes));
 
     callback(Common::GetStringT("Done compressing disc image."), 1.0f);
   }
@@ -385,15 +383,10 @@ bool ConvertToGCZ(BlobReader* infile, const std::string& infile_path,
   return result == ConversionResultCode::Success;
 }
 
-bool IsGCZBlob(File::IOFile& file)
+bool IsGCZBlob(File::DirectIOFile& file)
 {
-  const u64 position = file.Tell();
-  if (!file.Seek(0, File::SeekOrigin::Begin))
-    return false;
   CompressedBlobHeader header;
-  bool is_gcz = file.ReadArray(&header, 1) && header.magic_cookie == GCZ_MAGIC;
-  file.Seek(position, File::SeekOrigin::Begin);
-  return is_gcz;
+  return file.OffsetRead(0, Common::AsWritableU8Span(header)) && header.magic_cookie == GCZ_MAGIC;
 }
 
 }  // namespace DiscIO
diff --git a/Source/Core/DiscIO/CompressedBlob.h b/Source/Core/DiscIO/CompressedBlob.h
index 15eeffc3db..5122403f47 100644
--- a/Source/Core/DiscIO/CompressedBlob.h
+++ b/Source/Core/DiscIO/CompressedBlob.h
@@ -17,7 +17,7 @@
 #include <vector>
 
 #include "Common/CommonTypes.h"
-#include "Common/IOFile.h"
+#include "Common/DirectIOFile.h"
 #include "DiscIO/Blob.h"
 
 namespace DiscIO
@@ -43,7 +43,7 @@ struct CompressedBlobHeader  // 32 bytes
 class CompressedBlobReader final : public SectorReader
 {
 public:
-  static std::unique_ptr<CompressedBlobReader> Create(File::IOFile file,
+  static std::unique_ptr<CompressedBlobReader> Create(File::DirectIOFile file,
                                                       const std::string& filename);
   ~CompressedBlobReader() override;
 
@@ -65,13 +65,13 @@ public:
   bool GetBlock(u64 block_num, u8* out_ptr) override;
 
 private:
-  CompressedBlobReader(File::IOFile file, const std::string& filename);
+  CompressedBlobReader(File::DirectIOFile file, const std::string& filename);
 
   CompressedBlobHeader m_header;
   std::vector<u64> m_block_pointers;
   std::vector<u32> m_hashes;
   int m_data_offset;
-  File::IOFile m_file;
+  File::DirectIOFile m_file;
   u64 m_file_size;
   std::vector<u8> m_zlib_buffer;
   std::string m_file_name;
diff --git a/Source/Core/DiscIO/DirectoryBlob.cpp b/Source/Core/DiscIO/DirectoryBlob.cpp
index d0ee8bf803..11acc8eb41 100644
--- a/Source/Core/DiscIO/DirectoryBlob.cpp
+++ b/Source/Core/DiscIO/DirectoryBlob.cpp
@@ -4,9 +4,7 @@
 #include "DiscIO/DirectoryBlob.h"
 
 #include <algorithm>
-#include <array>
 #include <cstring>
-#include <locale>
 #include <map>
 #include <memory>
 #include <set>
@@ -17,14 +15,12 @@
 
 #include "Common/Align.h"
 #include "Common/Assert.h"
-#include "Common/CommonPaths.h"
 #include "Common/CommonTypes.h"
+#include "Common/DirectIOFile.h"
 #include "Common/FileUtil.h"
-#include "Common/IOFile.h"
 #include "Common/Logging/Log.h"
 #include "Common/StringUtil.h"
 #include "Common/Swap.h"
-#include "Core/Boot/DolReader.h"
 #include "Core/IOS/ES/Formats.h"
 #include "DiscIO/Blob.h"
 #include "DiscIO/DiscUtils.h"
@@ -97,9 +93,8 @@ bool DiscContent::Read(u64* offset, u64* length, u8** buffer, DirectoryBlobReade
     if (std::holds_alternative<ContentFile>(m_content_source))
     {
       const auto& content = std::get<ContentFile>(m_content_source);
-      File::IOFile file(content.m_filename, "rb");
-      if (!file.Seek(content.m_offset + offset_in_content, File::SeekOrigin::Begin) ||
-          !file.ReadBytes(*buffer, bytes_to_read))
+      File::DirectIOFile file(content.m_filename, File::AccessMode::Read);
+      if (!file.OffsetRead(content.m_offset + offset_in_content, *buffer, bytes_to_read))
       {
         return false;
       }
@@ -1013,9 +1008,9 @@ void DirectoryBlobPartition::SetBI2(std::vector<u8> bi2)
 
 u64 DirectoryBlobPartition::SetApploaderFromFile(const std::string& path)
 {
-  File::IOFile file(path, "rb");
+  File::DirectIOFile file(path, File::AccessMode::Read);
   std::vector<u8> apploader(file.GetSize());
-  file.ReadBytes(apploader.data(), apploader.size());
+  file.Read(apploader);
   return SetApploader(std::move(apploader), path);
 }
 
@@ -1256,10 +1251,9 @@ void DirectoryBlobPartition::WriteDirectory(std::vector<u8>* fst_data,
 
 static size_t ReadFileToVector(const std::string& path, std::vector<u8>* vector)
 {
-  File::IOFile file(path, "rb");
-  size_t bytes_read;
-  file.ReadArray<u8>(vector->data(), std::min<u64>(file.GetSize(), vector->size()), &bytes_read);
-  return bytes_read;
+  File::DirectIOFile file(path, File::AccessMode::Read);
+  file.Read(vector->data(), std::min<u64>(file.GetSize(), vector->size()));
+  return file.Tell();
 }
 
 static void PadToAddress(u64 start_address, u64* address, u64* length, u8** buffer)
diff --git a/Source/Core/DiscIO/DirectoryBlob.h b/Source/Core/DiscIO/DirectoryBlob.h
index 12d546f909..baea8d9e85 100644
--- a/Source/Core/DiscIO/DirectoryBlob.h
+++ b/Source/Core/DiscIO/DirectoryBlob.h
@@ -15,7 +15,6 @@
 #include <vector>
 
 #include "Common/CommonTypes.h"
-#include "Common/FileUtil.h"
 #include "DiscIO/Blob.h"
 #include "DiscIO/Volume.h"
 #include "DiscIO/WiiEncryptionCache.h"
@@ -23,7 +22,6 @@
 namespace File
 {
 struct FSTEntry;
-class IOFile;
 }  // namespace File
 
 namespace DiscIO
diff --git a/Source/Core/DiscIO/FileBlob.cpp b/Source/Core/DiscIO/FileBlob.cpp
index 9ba572ea77..3a30e2a255 100644
--- a/Source/Core/DiscIO/FileBlob.cpp
+++ b/Source/Core/DiscIO/FileBlob.cpp
@@ -15,14 +15,14 @@
 
 namespace DiscIO
 {
-PlainFileReader::PlainFileReader(File::IOFile file) : m_file(std::move(file))
+PlainFileReader::PlainFileReader(File::DirectIOFile file) : m_file(std::move(file))
 {
   m_size = m_file.GetSize();
 }
 
-std::unique_ptr<PlainFileReader> PlainFileReader::Create(File::IOFile file)
+std::unique_ptr<PlainFileReader> PlainFileReader::Create(File::DirectIOFile file)
 {
-  if (file)
+  if (file.IsOpen())
     return std::unique_ptr<PlainFileReader>(new PlainFileReader(std::move(file)));
 
   return nullptr;
@@ -30,20 +30,12 @@ std::unique_ptr<PlainFileReader> PlainFileReader::Create(File::IOFile file)
 
 std::unique_ptr<BlobReader> PlainFileReader::CopyReader() const
 {
-  return Create(m_file.Duplicate("rb"));
+  return Create(m_file);
 }
 
 bool PlainFileReader::Read(u64 offset, u64 nbytes, u8* out_ptr)
 {
-  if (m_file.Seek(offset, File::SeekOrigin::Begin) && m_file.ReadBytes(out_ptr, nbytes))
-  {
-    return true;
-  }
-  else
-  {
-    m_file.ClearError();
-    return false;
-  }
+  return m_file.OffsetRead(offset, out_ptr, nbytes);
 }
 
 bool ConvertToPlain(BlobReader* infile, const std::string& infile_path,
@@ -51,8 +43,8 @@ bool ConvertToPlain(BlobReader* infile, const std::string& infile_path,
 {
   ASSERT(infile->GetDataSizeType() == DataSizeType::Accurate);
 
-  File::IOFile outfile(outfile_path, "wb");
-  if (!outfile)
+  File::DirectIOFile outfile(outfile_path, File::AccessMode::Write);
+  if (!outfile.IsOpen())
   {
     PanicAlertFmtT(
         "Failed to open the output file \"{0}\".\n"
@@ -99,7 +91,7 @@ bool ConvertToPlain(BlobReader* infile, const std::string& infile_path,
       success = false;
       break;
     }
-    if (!outfile.WriteBytes(buffer.data(), sz))
+    if (!outfile.Write(buffer.data(), sz))
     {
       PanicAlertFmtT("Failed to write the output file \"{0}\".\n"
                      "Check that you have enough space available on the target drive.",
diff --git a/Source/Core/DiscIO/FileBlob.h b/Source/Core/DiscIO/FileBlob.h
index 46224d9c3f..3e3a495343 100644
--- a/Source/Core/DiscIO/FileBlob.h
+++ b/Source/Core/DiscIO/FileBlob.h
@@ -3,12 +3,11 @@
 
 #pragma once
 
-#include <cstdio>
 #include <memory>
 #include <string>
 
 #include "Common/CommonTypes.h"
-#include "Common/IOFile.h"
+#include "Common/DirectIOFile.h"
 #include "DiscIO/Blob.h"
 
 namespace DiscIO
@@ -16,7 +15,7 @@ namespace DiscIO
 class PlainFileReader final : public BlobReader
 {
 public:
-  static std::unique_ptr<PlainFileReader> Create(File::IOFile file);
+  static std::unique_ptr<PlainFileReader> Create(File::DirectIOFile file);
 
   BlobType GetBlobType() const override { return BlobType::PLAIN; }
   std::unique_ptr<BlobReader> CopyReader() const override;
@@ -33,9 +32,9 @@ public:
   bool Read(u64 offset, u64 nbytes, u8* out_ptr) override;
 
 private:
-  PlainFileReader(File::IOFile file);
+  PlainFileReader(File::DirectIOFile file);
 
-  File::IOFile m_file;
+  File::DirectIOFile m_file;
   u64 m_size;
 };
 
diff --git a/Source/Core/DiscIO/NFSBlob.cpp b/Source/Core/DiscIO/NFSBlob.cpp
index f051ec9832..df6a65f321 100644
--- a/Source/Core/DiscIO/NFSBlob.cpp
+++ b/Source/Core/DiscIO/NFSBlob.cpp
@@ -15,9 +15,9 @@
 #include <fmt/format.h>
 
 #include "Common/Align.h"
+#include "Common/BitUtils.h"
 #include "Common/CommonTypes.h"
 #include "Common/Crypto/AES.h"
-#include "Common/IOFile.h"
 #include "Common/Logging/Log.h"
 #include "Common/StringUtil.h"
 #include "Common/Swap.h"
@@ -39,8 +39,8 @@ bool NFSFileReader::ReadKey(const std::string& path, const std::string& director
   }
 
   const std::string key_path = parent + "code/htk.bin";
-  File::IOFile key_file(key_path, "rb");
-  if (!key_file.ReadBytes(key_out->data(), key_out->size()))
+  File::DirectIOFile key_file(key_path, File::AccessMode::Read);
+  if (!key_file.Read(*key_out))
   {
     ERROR_LOG_FMT(DISCIO, "Failed to read from {}", key_path);
     return false;
@@ -67,13 +67,13 @@ std::vector<NFSLBARange> NFSFileReader::GetLBARanges(const NFSHeader& header)
   return lba_ranges;
 }
 
-std::vector<File::IOFile> NFSFileReader::OpenFiles(const std::string& directory,
-                                                   File::IOFile first_file, u64 expected_raw_size,
-                                                   u64* raw_size_out)
+std::vector<File::DirectIOFile> NFSFileReader::OpenFiles(const std::string& directory,
+                                                         File::DirectIOFile first_file,
+                                                         u64 expected_raw_size, u64* raw_size_out)
 {
   const u64 file_count = Common::AlignUp(expected_raw_size, MAX_FILE_SIZE) / MAX_FILE_SIZE;
 
-  std::vector<File::IOFile> files;
+  std::vector<File::DirectIOFile> files;
   files.reserve(file_count);
 
   *raw_size_out = first_file.GetSize();
@@ -82,8 +82,8 @@ std::vector<File::IOFile> NFSFileReader::OpenFiles(const std::string& directory,
   for (u64 i = 1; i < file_count; ++i)
   {
     const std::string child_path = fmt::format("{}hif_{:06}.nfs", directory, i);
-    File::IOFile child(child_path, "rb");
-    if (!child)
+    File::DirectIOFile child(child_path, File::AccessMode::Read);
+    if (!child.IsOpen())
     {
       ERROR_LOG_FMT(DISCIO, "Failed to open {}", child_path);
       return {};
@@ -123,7 +123,7 @@ u64 NFSFileReader::CalculateExpectedDataSize(const std::vector<NFSLBARange>& lba
   return u64(greatest_block_index) * BLOCK_SIZE;
 }
 
-std::unique_ptr<NFSFileReader> NFSFileReader::Create(File::IOFile first_file,
+std::unique_ptr<NFSFileReader> NFSFileReader::Create(File::DirectIOFile first_file,
                                                      const std::string& path)
 {
   std::string directory, filename, extension;
@@ -136,18 +136,15 @@ std::unique_ptr<NFSFileReader> NFSFileReader::Create(File::IOFile first_file,
     return nullptr;
 
   NFSHeader header;
-  if (!first_file.Seek(0, File::SeekOrigin::Begin) || !first_file.ReadArray(&header, 1) ||
-      header.magic != NFS_MAGIC)
-  {
+  if (!first_file.OffsetRead(0, Common::AsWritableU8Span(header)) || header.magic != NFS_MAGIC)
     return nullptr;
-  }
 
   std::vector<NFSLBARange> lba_ranges = GetLBARanges(header);
 
   const u64 expected_raw_size = CalculateExpectedRawSize(lba_ranges);
 
   u64 raw_size;
-  std::vector<File::IOFile> files =
+  std::vector<File::DirectIOFile> files =
       OpenFiles(directory, std::move(first_file), expected_raw_size, &raw_size);
 
   if (files.empty())
@@ -157,8 +154,8 @@ std::unique_ptr<NFSFileReader> NFSFileReader::Create(File::IOFile first_file,
       new NFSFileReader(std::move(lba_ranges), std::move(files), key, raw_size));
 }
 
-NFSFileReader::NFSFileReader(std::vector<NFSLBARange> lba_ranges, std::vector<File::IOFile> files,
-                             Key key, u64 raw_size)
+NFSFileReader::NFSFileReader(std::vector<NFSLBARange> lba_ranges,
+                             std::vector<File::DirectIOFile> files, Key key, u64 raw_size)
     : m_lba_ranges(std::move(lba_ranges)), m_files(std::move(files)),
       m_aes_context(Common::AES::CreateContextDecrypt(key.data())), m_raw_size(raw_size), m_key(key)
 {
@@ -167,11 +164,7 @@ NFSFileReader::NFSFileReader(std::vector<NFSLBARange> lba_ranges, std::vector<Fi
 
 std::unique_ptr<BlobReader> NFSFileReader::CopyReader() const
 {
-  std::vector<File::IOFile> new_files{};
-  for (const File::IOFile& file : m_files)
-    new_files.push_back(file.Duplicate("rb"));
-  return std::unique_ptr<NFSFileReader>(
-      new NFSFileReader(m_lba_ranges, std::move(new_files), m_key, m_raw_size));
+  return std::unique_ptr<BlobReader>{new NFSFileReader(m_lba_ranges, m_files, m_key, m_raw_size)};
 }
 
 u64 NFSFileReader::GetDataSize() const
@@ -208,6 +201,7 @@ bool NFSFileReader::ReadEncryptedBlock(u64 physical_block_index)
 
   const u64 file_index = physical_block_index / BLOCKS_PER_FILE;
   const u64 block_in_file = physical_block_index % BLOCKS_PER_FILE;
+  const u64 offset_in_file = sizeof(NFSHeader) + block_in_file * BLOCK_SIZE;
 
   if (block_in_file == BLOCKS_PER_FILE - 1)
   {
@@ -217,33 +211,23 @@ bool NFSFileReader::ReadEncryptedBlock(u64 physical_block_index)
     constexpr size_t PART_1_SIZE = BLOCK_SIZE - sizeof(NFSHeader);
     constexpr size_t PART_2_SIZE = sizeof(NFSHeader);
 
-    File::IOFile& file_1 = m_files[file_index];
-    File::IOFile& file_2 = m_files[file_index + 1];
+    File::DirectIOFile& file_1 = m_files[file_index];
+    File::DirectIOFile& file_2 = m_files[file_index + 1];
 
-    if (!file_1.Seek(sizeof(NFSHeader) + block_in_file * BLOCK_SIZE, File::SeekOrigin::Begin) ||
-        !file_1.ReadBytes(m_current_block_encrypted.data(), PART_1_SIZE))
-    {
-      file_1.ClearError();
+    if (!file_1.OffsetRead(offset_in_file, m_current_block_encrypted.data(), PART_1_SIZE))
       return false;
-    }
 
-    if (!file_2.Seek(0, File::SeekOrigin::Begin) ||
-        !file_2.ReadBytes(m_current_block_encrypted.data() + PART_1_SIZE, PART_2_SIZE))
-    {
-      file_2.ClearError();
+    if (!file_2.OffsetRead(0, m_current_block_encrypted.data() + PART_1_SIZE, PART_2_SIZE))
       return false;
-    }
   }
   else
   {
     // Normal case. The read is offset by 0x200 bytes, but it's all within one file.
 
-    File::IOFile& file = m_files[file_index];
+    File::DirectIOFile& file = m_files[file_index];
 
-    if (!file.Seek(sizeof(NFSHeader) + block_in_file * BLOCK_SIZE, File::SeekOrigin::Begin) ||
-        !file.ReadBytes(m_current_block_encrypted.data(), BLOCK_SIZE))
+    if (!file.OffsetRead(offset_in_file, m_current_block_encrypted.data(), BLOCK_SIZE))
     {
-      file.ClearError();
       return false;
     }
   }
diff --git a/Source/Core/DiscIO/NFSBlob.h b/Source/Core/DiscIO/NFSBlob.h
index cdcd20011f..dcbe6bf31a 100644
--- a/Source/Core/DiscIO/NFSBlob.h
+++ b/Source/Core/DiscIO/NFSBlob.h
@@ -11,7 +11,7 @@
 
 #include "Common/CommonTypes.h"
 #include "Common/Crypto/AES.h"
-#include "Common/IOFile.h"
+#include "Common/DirectIOFile.h"
 #include "DiscIO/Blob.h"
 
 // This is the file format used for Wii games released on the Wii U eShop.
@@ -41,7 +41,7 @@ static_assert(sizeof(NFSHeader) == 0x200);
 class NFSFileReader final : public BlobReader
 {
 public:
-  static std::unique_ptr<NFSFileReader> Create(File::IOFile first_file,
+  static std::unique_ptr<NFSFileReader> Create(File::DirectIOFile first_file,
                                                const std::string& directory_path);
 
   BlobType GetBlobType() const override { return BlobType::NFS; }
@@ -65,12 +65,13 @@ private:
 
   static bool ReadKey(const std::string& path, const std::string& directory, Key* key_out);
   static std::vector<NFSLBARange> GetLBARanges(const NFSHeader& header);
-  static std::vector<File::IOFile> OpenFiles(const std::string& directory, File::IOFile first_file,
-                                             u64 expected_raw_size, u64* raw_size_out);
+  static std::vector<File::DirectIOFile> OpenFiles(const std::string& directory,
+                                                   File::DirectIOFile first_file,
+                                                   u64 expected_raw_size, u64* raw_size_out);
   static u64 CalculateExpectedRawSize(const std::vector<NFSLBARange>& lba_ranges);
   static u64 CalculateExpectedDataSize(const std::vector<NFSLBARange>& lba_ranges);
 
-  NFSFileReader(std::vector<NFSLBARange> lba_ranges, std::vector<File::IOFile> files, Key key,
+  NFSFileReader(std::vector<NFSLBARange> lba_ranges, std::vector<File::DirectIOFile> files, Key key,
                 u64 raw_size);
 
   u64 ToPhysicalBlockIndex(u64 logical_block_index) const;
@@ -83,7 +84,7 @@ private:
   u64 m_current_logical_block_index = std::numeric_limits<u64>::max();
 
   std::vector<NFSLBARange> m_lba_ranges;
-  std::vector<File::IOFile> m_files;
+  std::vector<File::DirectIOFile> m_files;
   std::unique_ptr<Common::AES::Context> m_aes_context;
   u64 m_raw_size;
   u64 m_data_size;
diff --git a/Source/Core/DiscIO/SplitFileBlob.cpp b/Source/Core/DiscIO/SplitFileBlob.cpp
index 4756088a40..c6a3dbd987 100644
--- a/Source/Core/DiscIO/SplitFileBlob.cpp
+++ b/Source/Core/DiscIO/SplitFileBlob.cpp
@@ -4,17 +4,11 @@
 #include "DiscIO/SplitFileBlob.h"
 
 #include <memory>
-#include <string>
 #include <string_view>
 #include <vector>
 
 #include <fmt/format.h>
 
-#include "Common/Assert.h"
-#include "Common/FileUtil.h"
-#include "Common/IOFile.h"
-#include "Common/MsgHandler.h"
-
 namespace DiscIO
 {
 SplitPlainFileReader::SplitPlainFileReader(std::vector<SingleFile> files)
@@ -38,7 +32,7 @@ std::unique_ptr<SplitPlainFileReader> SplitPlainFileReader::Create(std::string_v
   u64 offset = 0;
   while (true)
   {
-    File::IOFile f(fmt::format("{}.part{}.iso", base_path, index), "rb");
+    File::DirectIOFile f(fmt::format("{}.part{}.iso", base_path, index), File::AccessMode::Read);
     if (!f.IsOpen())
       break;
     const u64 size = f.GetSize();
@@ -58,13 +52,7 @@ std::unique_ptr<SplitPlainFileReader> SplitPlainFileReader::Create(std::string_v
 
 std::unique_ptr<BlobReader> SplitPlainFileReader::CopyReader() const
 {
-  std::vector<SingleFile> new_files{};
-  for (const SingleFile& file : m_files)
-  {
-    new_files.push_back(
-        {.file = file.file.Duplicate("rb"), .offset = file.offset, .size = file.size});
-  }
-  return std::unique_ptr<SplitPlainFileReader>(new SplitPlainFileReader(std::move(new_files)));
+  return std::unique_ptr<SplitPlainFileReader>{new SplitPlainFileReader(m_files)};
 }
 
 bool SplitPlainFileReader::Read(u64 offset, u64 nbytes, u8* out_ptr)
@@ -80,13 +68,10 @@ bool SplitPlainFileReader::Read(u64 offset, u64 nbytes, u8* out_ptr)
     if (current_offset >= file.offset && current_offset < file.offset + file.size)
     {
       auto& f = file.file;
-      const u64 seek_offset = current_offset - file.offset;
-      const u64 current_read = std::min(file.size - seek_offset, rest);
-      if (!f.Seek(seek_offset, File::SeekOrigin::Begin) || !f.ReadBytes(out, current_read))
-      {
-        f.ClearError();
+      const u64 offset_in_file = current_offset - file.offset;
+      const u64 current_read = std::min(file.size - offset_in_file, rest);
+      if (!f.OffsetRead(offset_in_file, out, current_read))
         return false;
-      }
 
       rest -= current_read;
       if (rest == 0)
diff --git a/Source/Core/DiscIO/SplitFileBlob.h b/Source/Core/DiscIO/SplitFileBlob.h
index d3268dca80..4c1fe96380 100644
--- a/Source/Core/DiscIO/SplitFileBlob.h
+++ b/Source/Core/DiscIO/SplitFileBlob.h
@@ -10,7 +10,7 @@
 #include <vector>
 
 #include "Common/CommonTypes.h"
-#include "Common/IOFile.h"
+#include "Common/DirectIOFile.h"
 #include "DiscIO/Blob.h"
 
 namespace DiscIO
@@ -37,7 +37,7 @@ public:
 private:
   struct SingleFile
   {
-    File::IOFile file;
+    File::DirectIOFile file;
     u64 offset;
     u64 size;
   };
diff --git a/Source/Core/DiscIO/TGCBlob.cpp b/Source/Core/DiscIO/TGCBlob.cpp
index 6478ea40da..5b33649fc6 100644
--- a/Source/Core/DiscIO/TGCBlob.cpp
+++ b/Source/Core/DiscIO/TGCBlob.cpp
@@ -5,12 +5,11 @@
 
 #include <algorithm>
 #include <memory>
-#include <string>
 #include <type_traits>
 #include <utility>
 #include <vector>
 
-#include "Common/IOFile.h"
+#include "Common/BitUtils.h"
 #include "Common/Swap.h"
 
 namespace
@@ -45,11 +44,10 @@ void Replace(u64 offset, u64 size, u8* out_ptr, u64 replace_offset, const T& rep
 
 namespace DiscIO
 {
-std::unique_ptr<TGCFileReader> TGCFileReader::Create(File::IOFile file)
+std::unique_ptr<TGCFileReader> TGCFileReader::Create(File::DirectIOFile file)
 {
   TGCHeader header;
-  if (file.Seek(0, File::SeekOrigin::Begin) && file.ReadArray(&header, 1) &&
-      header.magic == TGC_MAGIC)
+  if (file.OffsetRead(0, Common::AsWritableU8Span(header)) && header.magic == TGC_MAGIC)
   {
     return std::unique_ptr<TGCFileReader>(new TGCFileReader(std::move(file)));
   }
@@ -57,18 +55,16 @@ std::unique_ptr<TGCFileReader> TGCFileReader::Create(File::IOFile file)
   return nullptr;
 }
 
-TGCFileReader::TGCFileReader(File::IOFile file) : m_file(std::move(file))
+TGCFileReader::TGCFileReader(File::DirectIOFile file) : m_file(std::move(file))
 {
-  m_file.Seek(0, File::SeekOrigin::Begin);
-  m_file.ReadArray(&m_header, 1);
+  m_file.OffsetRead(0, Common::AsWritableU8Span(m_header));
 
   m_size = m_file.GetSize();
 
   const u32 fst_offset = Common::swap32(m_header.fst_real_offset);
   const u32 fst_size = Common::swap32(m_header.fst_size);
   m_fst.resize(fst_size);
-  if (!m_file.Seek(fst_offset, File::SeekOrigin::Begin) ||
-      !m_file.ReadBytes(m_fst.data(), m_fst.size()))
+  if (!m_file.OffsetRead(fst_offset, m_fst))
   {
     m_fst.clear();
   }
@@ -100,7 +96,7 @@ TGCFileReader::TGCFileReader(File::IOFile file) : m_file(std::move(file))
 
 std::unique_ptr<BlobReader> TGCFileReader::CopyReader() const
 {
-  return Create(m_file.Duplicate("rb"));
+  return Create(m_file);
 }
 
 u64 TGCFileReader::GetDataSize() const
@@ -112,8 +108,7 @@ bool TGCFileReader::Read(u64 offset, u64 nbytes, u8* out_ptr)
 {
   const u32 tgc_header_size = Common::swap32(m_header.tgc_header_size);
 
-  if (m_file.Seek(offset + tgc_header_size, File::SeekOrigin::Begin) &&
-      m_file.ReadBytes(out_ptr, nbytes))
+  if (m_file.OffsetRead(offset + tgc_header_size, out_ptr, nbytes))
   {
     const u32 replacement_dol_offset = SubtractBE32(m_header.dol_real_offset, tgc_header_size);
     const u32 replacement_fst_offset = SubtractBE32(m_header.fst_real_offset, tgc_header_size);
@@ -126,7 +121,6 @@ bool TGCFileReader::Read(u64 offset, u64 nbytes, u8* out_ptr)
     return true;
   }
 
-  m_file.ClearError();
   return false;
 }
 
diff --git a/Source/Core/DiscIO/TGCBlob.h b/Source/Core/DiscIO/TGCBlob.h
index 2952f2809f..1271fa9253 100644
--- a/Source/Core/DiscIO/TGCBlob.h
+++ b/Source/Core/DiscIO/TGCBlob.h
@@ -4,11 +4,10 @@
 #pragma once
 
 #include <memory>
-#include <utility>
 #include <vector>
 
 #include "Common/CommonTypes.h"
-#include "Common/IOFile.h"
+#include "Common/DirectIOFile.h"
 #include "DiscIO/Blob.h"
 
 namespace DiscIO
@@ -39,7 +38,7 @@ struct TGCHeader
 class TGCFileReader final : public BlobReader
 {
 public:
-  static std::unique_ptr<TGCFileReader> Create(File::IOFile file);
+  static std::unique_ptr<TGCFileReader> Create(File::DirectIOFile file);
 
   BlobType GetBlobType() const override { return BlobType::TGC; }
   std::unique_ptr<BlobReader> CopyReader() const override;
@@ -56,9 +55,9 @@ public:
   bool Read(u64 offset, u64 nbytes, u8* out_ptr) override;
 
 private:
-  TGCFileReader(File::IOFile file);
+  TGCFileReader(File::DirectIOFile file);
 
-  File::IOFile m_file;
+  File::DirectIOFile m_file;
   u64 m_size;
 
   std::vector<u8> m_fst;
diff --git a/Source/Core/DiscIO/WIABlob.cpp b/Source/Core/DiscIO/WIABlob.cpp
index 18cdb04d4b..01baf6a83a 100644
--- a/Source/Core/DiscIO/WIABlob.cpp
+++ b/Source/Core/DiscIO/WIABlob.cpp
@@ -19,10 +19,10 @@
 
 #include "Common/Align.h"
 #include "Common/Assert.h"
+#include "Common/BitUtils.h"
 #include "Common/CommonTypes.h"
 #include "Common/Crypto/SHA1.h"
 #include "Common/FileUtil.h"
-#include "Common/IOFile.h"
 #include "Common/Logging/Log.h"
 #include "Common/MsgHandler.h"
 #include "Common/ScopeGuard.h"
@@ -78,7 +78,7 @@ std::pair<int, int> GetAllowedCompressionLevels(WIARVZCompressionType compressio
 }
 
 template <bool RVZ>
-WIARVZFileReader<RVZ>::WIARVZFileReader(File::IOFile file, const std::string& path)
+WIARVZFileReader<RVZ>::WIARVZFileReader(File::DirectIOFile file, const std::string& path)
     : m_file(std::move(file)), m_path(path), m_encryption_cache(this)
 {
   m_valid = Initialize(path);
@@ -90,8 +90,11 @@ WIARVZFileReader<RVZ>::~WIARVZFileReader() = default;
 template <bool RVZ>
 bool WIARVZFileReader<RVZ>::Initialize(const std::string& path)
 {
-  if (!m_file.Seek(0, File::SeekOrigin::Begin) || !m_file.ReadArray(&m_header_1, 1))
+  if (!m_file.Seek(0, File::SeekOrigin::Begin) ||
+      !m_file.Read(Common::AsWritableU8Span(m_header_1)))
+  {
     return false;
+  }
 
   if ((!RVZ && m_header_1.magic != WIA_MAGIC) || (RVZ && m_header_1.magic != RVZ_MAGIC))
     return false;
@@ -126,7 +129,7 @@ bool WIARVZFileReader<RVZ>::Initialize(const std::string& path)
     return false;
 
   std::vector<u8> header_2(header_2_size);
-  if (!m_file.ReadBytes(header_2.data(), header_2.size()))
+  if (!m_file.Read(header_2))
     return false;
 
   const auto header_2_actual_hash = Common::SHA1::CalculateDigest(header_2);
@@ -161,10 +164,10 @@ bool WIARVZFileReader<RVZ>::Initialize(const std::string& path)
   const size_t number_of_partition_entries = Common::swap32(m_header_2.number_of_partition_entries);
   const size_t partition_entry_size = Common::swap32(m_header_2.partition_entry_size);
   std::vector<u8> partition_entries(partition_entry_size * number_of_partition_entries);
-  if (!m_file.Seek(Common::swap64(m_header_2.partition_entries_offset), File::SeekOrigin::Begin))
-    return false;
-  if (!m_file.ReadBytes(partition_entries.data(), partition_entries.size()))
+  if (!m_file.OffsetRead(Common::swap64(m_header_2.partition_entries_offset), partition_entries))
+  {
     return false;
+  }
 
   const auto partition_entries_actual_hash = Common::SHA1::CalculateDigest(partition_entries);
   if (m_header_2.partition_entries_hash != partition_entries_actual_hash)
@@ -273,7 +276,7 @@ bool WIARVZFileReader<RVZ>::HasDataOverlap() const
 }
 
 template <bool RVZ>
-std::unique_ptr<WIARVZFileReader<RVZ>> WIARVZFileReader<RVZ>::Create(File::IOFile file,
+std::unique_ptr<WIARVZFileReader<RVZ>> WIARVZFileReader<RVZ>::Create(File::DirectIOFile file,
                                                                      const std::string& path)
 {
   std::unique_ptr<WIARVZFileReader> blob(new WIARVZFileReader(std::move(file), path));
@@ -289,7 +292,7 @@ BlobType WIARVZFileReader<RVZ>::GetBlobType() const
 template <bool RVZ>
 std::unique_ptr<BlobReader> WIARVZFileReader<RVZ>::CopyReader() const
 {
-  return Create(m_file.Duplicate("rb"), m_path);
+  return Create(m_file, m_path);
 }
 
 template <bool RVZ>
@@ -628,8 +631,8 @@ template <bool RVZ>
 WIARVZFileReader<RVZ>::Chunk::Chunk() = default;
 
 template <bool RVZ>
-WIARVZFileReader<RVZ>::Chunk::Chunk(File::IOFile* file, u64 offset_in_file, u64 compressed_size,
-                                    u64 decompressed_size, u32 exception_lists,
+WIARVZFileReader<RVZ>::Chunk::Chunk(File::DirectIOFile* file, u64 offset_in_file,
+                                    u64 compressed_size, u64 decompressed_size, u32 exception_lists,
                                     bool compressed_exception_lists, u32 rvz_packed_size,
                                     u64 data_offset, std::unique_ptr<Decompressor> decompressor)
     : m_decompressor(std::move(decompressor)), m_file(file), m_offset_in_file(offset_in_file),
@@ -691,9 +694,7 @@ bool WIARVZFileReader<RVZ>::Chunk::Read(u64 offset, u64 size, u8* out_ptr)
       return false;
     }
 
-    if (!m_file->Seek(m_offset_in_file, File::SeekOrigin::Begin))
-      return false;
-    if (!m_file->ReadBytes(m_in.data.data() + m_in.bytes_written, bytes_to_read))
+    if (!m_file->OffsetRead(m_offset_in_file, m_in.data.data() + m_in.bytes_written, bytes_to_read))
       return false;
 
     m_offset_in_file += bytes_to_read;
@@ -881,7 +882,7 @@ bool WIARVZFileReader<RVZ>::ApplyHashExceptions(
 }
 
 template <bool RVZ>
-bool WIARVZFileReader<RVZ>::PadTo4(File::IOFile* file, u64* bytes_written)
+bool WIARVZFileReader<RVZ>::PadTo4(File::DirectIOFile* file, u64* bytes_written)
 {
   constexpr u32 ZEROES = 0;
   const u64 bytes_to_write = Common::AlignUp(*bytes_written, 4) - *bytes_written;
@@ -889,7 +890,7 @@ bool WIARVZFileReader<RVZ>::PadTo4(File::IOFile* file, u64* bytes_written)
     return true;
 
   *bytes_written += bytes_to_write;
-  return file->WriteBytes(&ZEROES, bytes_to_write);
+  return file->Write(Common::AsU8Span(ZEROES).first(bytes_to_write));
 }
 
 template <bool RVZ>
@@ -1646,7 +1647,7 @@ WIARVZFileReader<RVZ>::ProcessAndCompress(CompressThreadState* state, CompressPa
 
 template <bool RVZ>
 ConversionResultCode WIARVZFileReader<RVZ>::Output(std::vector<OutputParametersEntry>* entries,
-                                                   File::IOFile* outfile,
+                                                   File::DirectIOFile* outfile,
                                                    std::map<ReuseID, GroupEntry>* reusable_groups,
                                                    std::mutex* reusable_groups_mutex,
                                                    GroupEntry* group_entry, u64* bytes_written)
@@ -1675,9 +1676,9 @@ ConversionResultCode WIARVZFileReader<RVZ>::Output(std::vector<OutputParametersE
     }
     group_entry->data_size = Common::swap32(data_size);
 
-    if (!outfile->WriteArray(entry.exception_lists.data(), entry.exception_lists.size()))
+    if (!outfile->Write(entry.exception_lists))
       return ConversionResultCode::WriteFailed;
-    if (!outfile->WriteArray(entry.main_data.data(), entry.main_data.size()))
+    if (!outfile->Write(entry.main_data))
       return ConversionResultCode::WriteFailed;
 
     *bytes_written += entry.exception_lists.size() + entry.main_data.size();
@@ -1716,7 +1717,7 @@ ConversionResultCode WIARVZFileReader<RVZ>::RunCallback(size_t groups_written, u
 }
 
 template <bool RVZ>
-bool WIARVZFileReader<RVZ>::WriteHeader(File::IOFile* file, const u8* data, size_t size,
+bool WIARVZFileReader<RVZ>::WriteHeader(File::DirectIOFile* file, const u8* data, size_t size,
                                         u64 upper_bound, u64* bytes_written, u64* offset_out)
 {
   // The first part of the check is to prevent this from running more than once. If *bytes_written
@@ -1731,7 +1732,7 @@ bool WIARVZFileReader<RVZ>::WriteHeader(File::IOFile* file, const u8* data, size
   }
 
   *offset_out = *bytes_written;
-  if (!file->WriteArray(data, size))
+  if (!file->Write(data, size))
     return false;
   *bytes_written += size;
   return PadTo4(file, bytes_written);
@@ -1740,7 +1741,7 @@ bool WIARVZFileReader<RVZ>::WriteHeader(File::IOFile* file, const u8* data, size
 template <bool RVZ>
 ConversionResultCode
 WIARVZFileReader<RVZ>::Convert(BlobReader* infile, const VolumeDisc* infile_volume,
-                               File::IOFile* outfile, WIARVZCompressionType compression_type,
+                               File::DirectIOFile* outfile, WIARVZCompressionType compression_type,
                                int compression_level, int chunk_size, CompressCB callback)
 {
   ASSERT(infile->GetDataSizeType() == DataSizeType::Accurate);
@@ -1806,7 +1807,7 @@ WIARVZFileReader<RVZ>::Convert(BlobReader* infile, const VolumeDisc* infile_volu
   std::vector<u8> buffer;
 
   buffer.resize(headers_size_upper_bound);
-  outfile->WriteBytes(buffer.data(), buffer.size());
+  outfile->Write(buffer);
   bytes_written = headers_size_upper_bound;
 
   if (!infile->Read(0, header_2.disc_header.size(), header_2.disc_header.data()))
@@ -2029,9 +2030,9 @@ WIARVZFileReader<RVZ>::Convert(BlobReader* infile, const VolumeDisc* infile_volu
   if (!outfile->Seek(0, File::SeekOrigin::Begin))
     return ConversionResultCode::WriteFailed;
 
-  if (!outfile->WriteArray(&header_1, 1))
+  if (!outfile->Write(Common::AsU8Span(header_1)))
     return ConversionResultCode::WriteFailed;
-  if (!outfile->WriteArray(&header_2, 1))
+  if (!outfile->Write(Common::AsU8Span(header_2)))
     return ConversionResultCode::WriteFailed;
 
   return ConversionResultCode::Success;
@@ -2042,8 +2043,8 @@ bool ConvertToWIAOrRVZ(BlobReader* infile, const std::string& infile_path,
                        WIARVZCompressionType compression_type, int compression_level,
                        int chunk_size, const CompressCB& callback)
 {
-  File::IOFile outfile(outfile_path, "wb");
-  if (!outfile)
+  File::DirectIOFile outfile(outfile_path, File::AccessMode::Write);
+  if (!outfile.IsOpen())
   {
     PanicAlertFmtT(
         "Failed to open the output file \"{0}\".\n"
diff --git a/Source/Core/DiscIO/WIABlob.h b/Source/Core/DiscIO/WIABlob.h
index f42a7f4c73..5e4bc26c92 100644
--- a/Source/Core/DiscIO/WIABlob.h
+++ b/Source/Core/DiscIO/WIABlob.h
@@ -13,7 +13,7 @@
 
 #include "Common/CommonTypes.h"
 #include "Common/Crypto/SHA1.h"
-#include "Common/IOFile.h"
+#include "Common/DirectIOFile.h"
 #include "Common/Swap.h"
 #include "DiscIO/Blob.h"
 #include "DiscIO/MultithreadedCompressor.h"
@@ -46,7 +46,7 @@ class WIARVZFileReader final : public BlobReader
 public:
   ~WIARVZFileReader() override;
 
-  static std::unique_ptr<WIARVZFileReader> Create(File::IOFile file, const std::string& path);
+  static std::unique_ptr<WIARVZFileReader> Create(File::DirectIOFile file, const std::string& path);
 
   BlobType GetBlobType() const override;
   std::unique_ptr<BlobReader> CopyReader() const override;
@@ -68,8 +68,9 @@ public:
   bool ReadWiiDecrypted(u64 offset, u64 size, u8* out_ptr, u64 partition_data_offset) override;
 
   static ConversionResultCode Convert(BlobReader* infile, const VolumeDisc* infile_volume,
-                                      File::IOFile* outfile, WIARVZCompressionType compression_type,
-                                      int compression_level, int chunk_size, CompressCB callback);
+                                      File::DirectIOFile* outfile,
+                                      WIARVZCompressionType compression_type, int compression_level,
+                                      int chunk_size, CompressCB callback);
 
 private:
   using WiiKey = std::array<u8, 16>;
@@ -188,7 +189,7 @@ private:
   {
   public:
     Chunk();
-    Chunk(File::IOFile* file, u64 offset_in_file, u64 compressed_size, u64 decompressed_size,
+    Chunk(File::DirectIOFile* file, u64 offset_in_file, u64 compressed_size, u64 decompressed_size,
           u32 exception_lists, bool compressed_exception_lists, u32 rvz_packed_size,
           u64 data_offset, std::unique_ptr<Decompressor> decompressor);
 
@@ -216,7 +217,7 @@ private:
     size_t m_in_bytes_read = 0;
 
     std::unique_ptr<Decompressor> m_decompressor = nullptr;
-    File::IOFile* m_file = nullptr;
+    File::DirectIOFile* m_file = nullptr;
     u64 m_offset_in_file = 0;
 
     size_t m_out_bytes_allocated_for_exceptions = 0;
@@ -228,7 +229,7 @@ private:
     u64 m_data_offset = 0;
   };
 
-  explicit WIARVZFileReader(File::IOFile file, const std::string& path);
+  explicit WIARVZFileReader(File::DirectIOFile file, const std::string& path);
   bool Initialize(const std::string& path);
   bool HasDataOverlap() const;
 
@@ -323,7 +324,7 @@ private:
     size_t group_index = 0;
   };
 
-  static bool PadTo4(File::IOFile* file, u64* bytes_written);
+  static bool PadTo4(File::DirectIOFile* file, u64* bytes_written);
   static void AddRawDataEntry(u64 offset, u64 size, int chunk_size, u32* total_groups,
                               std::vector<RawDataEntry>* raw_data_entries,
                               std::vector<DataEntry>* data_entries);
@@ -337,7 +338,7 @@ private:
       std::vector<DataEntry>* data_entries, std::vector<const FileSystem*>* partition_file_systems);
   static std::optional<std::vector<u8>> Compress(Compressor* compressor, const u8* data,
                                                  size_t size);
-  static bool WriteHeader(File::IOFile* file, const u8* data, size_t size, u64 upper_bound,
+  static bool WriteHeader(File::DirectIOFile* file, const u8* data, size_t size, u64 upper_bound,
                           u64* bytes_written, u64* offset_out);
 
   static void SetUpCompressor(std::unique_ptr<Compressor>* compressor,
@@ -354,7 +355,7 @@ private:
                      u64 exception_lists_per_chunk, bool compressed_exception_lists,
                      bool compression);
   static ConversionResultCode Output(std::vector<OutputParametersEntry>* entries,
-                                     File::IOFile* outfile,
+                                     File::DirectIOFile* outfile,
                                      std::map<ReuseID, GroupEntry>* reusable_groups,
                                      std::mutex* reusable_groups_mutex, GroupEntry* group_entry,
                                      u64* bytes_written);
@@ -365,7 +366,7 @@ private:
   bool m_valid;
   WIARVZCompressionType m_compression_type;
 
-  File::IOFile m_file;
+  File::DirectIOFile m_file;
   std::string m_path;
   Chunk m_cached_chunk;
   u64 m_cached_chunk_offset = std::numeric_limits<u64>::max();
diff --git a/Source/Core/DiscIO/WbfsBlob.cpp b/Source/Core/DiscIO/WbfsBlob.cpp
index 3f5852c46d..6f74497bfa 100644
--- a/Source/Core/DiscIO/WbfsBlob.cpp
+++ b/Source/Core/DiscIO/WbfsBlob.cpp
@@ -13,8 +13,8 @@
 
 #include "Common/Align.h"
 #include "Common/Assert.h"
+#include "Common/BitUtils.h"
 #include "Common/CommonTypes.h"
-#include "Common/IOFile.h"
 #include "Common/Logging/Log.h"
 #include "Common/Swap.h"
 
@@ -24,7 +24,7 @@ static constexpr u64 WII_SECTOR_SIZE = 0x8000;
 static constexpr u64 WII_SECTOR_COUNT = 143432 * 2;
 static constexpr u64 WII_DISC_HEADER_SIZE = 256;
 
-WbfsFileReader::WbfsFileReader(File::IOFile file, const std::string& path)
+WbfsFileReader::WbfsFileReader(File::DirectIOFile file, const std::string& path)
     : m_size(0), m_good(false)
 {
   if (!AddFileToList(std::move(file)))
@@ -39,7 +39,7 @@ WbfsFileReader::WbfsFileReader(File::IOFile file, const std::string& path)
   m_wlba_table.resize(m_blocks_per_disc);
   m_files[0].file.Seek(m_hd_sector_size + WII_DISC_HEADER_SIZE /*+ i * m_disc_info_size*/,
                        File::SeekOrigin::Begin);
-  m_files[0].file.ReadBytes(m_wlba_table.data(), m_blocks_per_disc * sizeof(u16));
+  m_files[0].file.Read(Common::AsWritableU8Span(m_wlba_table));
   for (size_t i = 0; i < m_blocks_per_disc; i++)
     m_wlba_table[i] = Common::swap16(m_wlba_table[i]);
 }
@@ -48,10 +48,9 @@ WbfsFileReader::~WbfsFileReader() = default;
 
 std::unique_ptr<BlobReader> WbfsFileReader::CopyReader() const
 {
-  auto retval =
-      std::unique_ptr<WbfsFileReader>(new WbfsFileReader(m_files[0].file.Duplicate("rb")));
+  auto retval = std::unique_ptr<WbfsFileReader>(new WbfsFileReader(m_files[0].file));
   for (size_t ix = 1; ix < m_files.size(); ix++)
-    retval->AddFileToList(m_files[ix].file.Duplicate("rb"));
+    retval->AddFileToList(m_files[ix].file);
   return retval;
 }
 
@@ -74,12 +73,12 @@ void WbfsFileReader::OpenAdditionalFiles(const std::string& path)
       return;
     std::string current_path = path;
     current_path.back() = static_cast<char>('0' + m_files.size());
-    if (!AddFileToList(File::IOFile(current_path, "rb")))
+    if (!AddFileToList(File::DirectIOFile(current_path, File::AccessMode::Read)))
       return;
   }
 }
 
-bool WbfsFileReader::AddFileToList(File::IOFile file)
+bool WbfsFileReader::AddFileToList(File::DirectIOFile file)
 {
   if (!file.IsOpen())
     return false;
@@ -95,7 +94,7 @@ bool WbfsFileReader::ReadHeader()
 {
   // Read hd size info
   m_files[0].file.Seek(0, File::SeekOrigin::Begin);
-  m_files[0].file.ReadBytes(&m_header, sizeof(WbfsHeader));
+  m_files[0].file.Read(Common::AsWritableU8Span(m_header));
   if (m_header.magic != WBFS_MAGIC)
     return false;
 
@@ -128,14 +127,13 @@ bool WbfsFileReader::Read(u64 offset, u64 nbytes, u8* out_ptr)
   while (nbytes)
   {
     u64 read_size;
-    File::IOFile& data_file = SeekToCluster(offset, &read_size);
+    auto& data_file = SeekToCluster(offset, &read_size);
     if (read_size == 0)
       return false;
     read_size = std::min(read_size, nbytes);
 
-    if (!data_file.ReadBytes(out_ptr, read_size))
+    if (!data_file.Read(out_ptr, read_size))
     {
-      data_file.ClearError();
       return false;
     }
 
@@ -147,7 +145,7 @@ bool WbfsFileReader::Read(u64 offset, u64 nbytes, u8* out_ptr)
   return true;
 }
 
-File::IOFile& WbfsFileReader::SeekToCluster(u64 offset, u64* available)
+File::DirectIOFile& WbfsFileReader::SeekToCluster(u64 offset, u64* available)
 {
   u64 base_cluster = (offset >> m_header.wbfs_sector_shift);
   if (base_cluster < m_blocks_per_disc)
@@ -180,7 +178,8 @@ File::IOFile& WbfsFileReader::SeekToCluster(u64 offset, u64* available)
   return m_files[0].file;
 }
 
-std::unique_ptr<WbfsFileReader> WbfsFileReader::Create(File::IOFile file, const std::string& path)
+std::unique_ptr<WbfsFileReader> WbfsFileReader::Create(File::DirectIOFile file,
+                                                       const std::string& path)
 {
   auto reader = std::unique_ptr<WbfsFileReader>(new WbfsFileReader(std::move(file), path));
 
diff --git a/Source/Core/DiscIO/WbfsBlob.h b/Source/Core/DiscIO/WbfsBlob.h
index 8e19f4999e..0423646b97 100644
--- a/Source/Core/DiscIO/WbfsBlob.h
+++ b/Source/Core/DiscIO/WbfsBlob.h
@@ -8,7 +8,7 @@
 #include <vector>
 
 #include "Common/CommonTypes.h"
-#include "Common/IOFile.h"
+#include "Common/DirectIOFile.h"
 #include "DiscIO/Blob.h"
 
 namespace DiscIO
@@ -20,7 +20,7 @@ class WbfsFileReader final : public BlobReader
 public:
   ~WbfsFileReader() override;
 
-  static std::unique_ptr<WbfsFileReader> Create(File::IOFile file, const std::string& path);
+  static std::unique_ptr<WbfsFileReader> Create(File::DirectIOFile file, const std::string& path);
 
   BlobType GetBlobType() const override { return BlobType::WBFS; }
   std::unique_ptr<BlobReader> CopyReader() const override;
@@ -37,22 +37,22 @@ public:
   bool Read(u64 offset, u64 nbytes, u8* out_ptr) override;
 
 private:
-  WbfsFileReader(File::IOFile file, const std::string& path = "");
+  WbfsFileReader(File::DirectIOFile file, const std::string& path = "");
 
   void OpenAdditionalFiles(const std::string& path);
-  bool AddFileToList(File::IOFile file);
+  bool AddFileToList(File::DirectIOFile file);
   bool ReadHeader();
 
-  File::IOFile& SeekToCluster(u64 offset, u64* available);
+  File::DirectIOFile& SeekToCluster(u64 offset, u64* available);
   bool IsGood() const { return m_good; }
   struct FileEntry
   {
-    FileEntry(File::IOFile file_, u64 base_address_, u64 size_)
+    FileEntry(File::DirectIOFile file_, u64 base_address_, u64 size_)
         : file(std::move(file_)), base_address(base_address_), size(size_)
     {
     }
 
-    File::IOFile file;
+    File::DirectIOFile file;
     u64 base_address;
     u64 size;
   };