1 files changed, 146 insertions, 0 deletions
diff --git a/src/core/file_sys/fssystem/fssystem_alignment_matching_storage.h b/src/core/file_sys/fssystem/fssystem_alignment_matching_storage.h
new file mode 100644
index 000000000..27d34fd17
--- /dev/null
+++ b/src/core/file_sys/fssystem/fssystem_alignment_matching_storage.h
@@ -0,0 +1,146 @@
+// SPDX-FileCopyrightText: Copyright 2023 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include "common/alignment.h"
+#include "core/file_sys/errors.h"
+#include "core/file_sys/fssystem/fs_i_storage.h"
+#include "core/file_sys/fssystem/fssystem_alignment_matching_storage_impl.h"
+#include "core/file_sys/fssystem/fssystem_pooled_buffer.h"
+
+namespace FileSys {
+
+template <size_t DataAlign_, size_t BufferAlign_>
+class AlignmentMatchingStorage : public IStorage {
+    YUZU_NON_COPYABLE(AlignmentMatchingStorage);
+    YUZU_NON_MOVEABLE(AlignmentMatchingStorage);
+
+public:
+    static constexpr size_t DataAlign = DataAlign_;
+    static constexpr size_t BufferAlign = BufferAlign_;
+
+    static constexpr size_t DataAlignMax = 0x200;
+    static_assert(DataAlign <= DataAlignMax);
+    static_assert(Common::IsPowerOfTwo(DataAlign));
+    static_assert(Common::IsPowerOfTwo(BufferAlign));
+
+private:
+    VirtualFile m_base_storage;
+    s64 m_base_storage_size;
+
+public:
+    explicit AlignmentMatchingStorage(VirtualFile bs) : m_base_storage(std::move(bs)) {}
+
+    virtual size_t Read(u8* buffer, size_t size, size_t offset) const override {
+        // Allocate a work buffer on stack.
+        alignas(DataAlignMax) char work_buf[DataAlign];
+
+        // Succeed if zero size.
+        if (size == 0) {
+            return size;
+        }
+
+        // Validate arguments.
+        ASSERT(buffer != nullptr);
+
+        s64 bs_size = this->GetSize();
+        ASSERT(R_SUCCEEDED(IStorage::CheckAccessRange(offset, size, bs_size)));
+
+        return AlignmentMatchingStorageImpl::Read(m_base_storage, work_buf, sizeof(work_buf),
+                                                  DataAlign, BufferAlign, offset, buffer, size);
+    }
+
+    virtual size_t Write(const u8* buffer, size_t size, size_t offset) override {
+        // Allocate a work buffer on stack.
+        alignas(DataAlignMax) char work_buf[DataAlign];
+
+        // Succeed if zero size.
+        if (size == 0) {
+            return size;
+        }
+
+        // Validate arguments.
+        ASSERT(buffer != nullptr);
+
+        s64 bs_size = this->GetSize();
+        ASSERT(R_SUCCEEDED(IStorage::CheckAccessRange(offset, size, bs_size)));
+
+        return AlignmentMatchingStorageImpl::Write(m_base_storage, work_buf, sizeof(work_buf),
+                                                   DataAlign, BufferAlign, offset, buffer, size);
+    }
+
+    virtual size_t GetSize() const override {
+        return m_base_storage->GetSize();
+    }
+};
+
+template <size_t BufferAlign_>
+class AlignmentMatchingStoragePooledBuffer : public IStorage {
+    YUZU_NON_COPYABLE(AlignmentMatchingStoragePooledBuffer);
+    YUZU_NON_MOVEABLE(AlignmentMatchingStoragePooledBuffer);
+
+public:
+    static constexpr size_t BufferAlign = BufferAlign_;
+
+    static_assert(Common::IsPowerOfTwo(BufferAlign));
+
+private:
+    VirtualFile m_base_storage;
+    s64 m_base_storage_size;
+    size_t m_data_align;
+
+public:
+    explicit AlignmentMatchingStoragePooledBuffer(VirtualFile bs, size_t da)
+        : m_base_storage(std::move(bs)), m_data_align(da) {
+        ASSERT(Common::IsPowerOfTwo(da));
+    }
+
+    virtual size_t Read(u8* buffer, size_t size, size_t offset) const override {
+        // Succeed if zero size.
+        if (size == 0) {
+            return size;
+        }
+
+        // Validate arguments.
+        ASSERT(buffer != nullptr);
+
+        s64 bs_size = this->GetSize();
+        ASSERT(R_SUCCEEDED(IStorage::CheckAccessRange(offset, size, bs_size)));
+
+        // Allocate a pooled buffer.
+        PooledBuffer pooled_buffer;
+        pooled_buffer.AllocateParticularlyLarge(m_data_align, m_data_align);
+
+        return AlignmentMatchingStorageImpl::Read(m_base_storage, pooled_buffer.GetBuffer(),
+                                                  pooled_buffer.GetSize(), m_data_align,
+                                                  BufferAlign, offset, buffer, size);
+    }
+
+    virtual size_t Write(const u8* buffer, size_t size, size_t offset) override {
+        // Succeed if zero size.
+        if (size == 0) {
+            return size;
+        }
+
+        // Validate arguments.
+        ASSERT(buffer != nullptr);
+
+        s64 bs_size = this->GetSize();
+        ASSERT(R_SUCCEEDED(IStorage::CheckAccessRange(offset, size, bs_size)));
+
+        // Allocate a pooled buffer.
+        PooledBuffer pooled_buffer;
+        pooled_buffer.AllocateParticularlyLarge(m_data_align, m_data_align);
+
+        return AlignmentMatchingStorageImpl::Write(m_base_storage, pooled_buffer.GetBuffer(),
+                                                   pooled_buffer.GetSize(), m_data_align,
+                                                   BufferAlign, offset, buffer, size);
+    }
+
+    virtual size_t GetSize() const override {
+        return m_base_storage->GetSize();
+    }
+};
+
+} // namespace FileSys