IoBuffer Class Reference

动态分配、对齐 IO 缓冲区的 RAII 封装 More...

#include <io_buffer.hpp>

Collaboration diagram for IoBuffer:

Public Member Functions
auto	GetBuffer () const -> std::span< const uint8_t >
	获取缓冲区数据与大小 (只读)
auto	GetBuffer () -> std::span< uint8_t >
	获取缓冲区数据与大小
auto	IsValid () const -> bool
	检查缓冲区是否有效
auto	ToDmaRegion (VirtToPhysFunc v2p=IdentityVirtToPhys) const -> DmaRegion
	创建此缓冲区的 DmaRegion 视图
构造/析构函数
	IoBuffer ()=default
	IoBuffer (size_t size, size_t alignment=kDefaultAlignment)
	构造函数
	~IoBuffer ()
	IoBuffer (const IoBuffer &)=delete
auto	operator= (const IoBuffer &) -> IoBuffer &=delete
	IoBuffer (IoBuffer &&other)
auto	operator= (IoBuffer &&other) noexcept -> IoBuffer &

Static Public Attributes
static constexpr size_t	kDefaultAlignment = 4096
	IO 缓冲区的默认对齐大小（如页大小）

Private Attributes
uint8_t *	data_ {nullptr}
	缓冲区数据指针
size_t	size_ {0}
	缓冲区大小

Detailed Description

动态分配、对齐 IO 缓冲区的 RAII 封装

Precondition

无

Postcondition

缓冲区内存已正确分配并对齐，析构时自动释放

Definition at line 85 of file io_buffer.hpp.

Constructor & Destructor Documentation

IoBuffer() [1/4]

IoBuffer::IoBuffer ( )

default

IoBuffer() [2/4]

IoBuffer::IoBuffer ( size_t  size, size_t  alignment = kDefaultAlignment  )

explicit

构造函数

IoBuffer mock for unit tests — uses malloc/free instead of aligned_alloc which requires the memory subsystem.

Parameters

size	缓冲区大小
alignment	对齐要求

Precondition

size > 0, alignment 必须是 2 的幂

Postcondition

缓冲区内存已正确分配并对齐

Copyright

Copyright The SimpleKernel Contributors

Definition at line 12 of file io_buffer.cpp.

                                                {
  assert(size > 0 && "IoBuffer size must be greater than 0");
  assert((alignment & (alignment - 1)) == 0 &&
         "IoBuffer alignment must be a power of 2");
 
  auto* data = static_cast<uint8_t*>(aligned_alloc(alignment, size));
  assert(data != nullptr && "IoBuffer aligned_alloc failed");
  data_ = data;
  size_ = size;
}

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~IoBuffer()

IoBuffer::~IoBuffer

(

)

Definition at line 23 of file io_buffer.cpp.

                    {
  assert((data_ == nullptr) == (size_ == 0) &&
         "IoBuffer invariant violated: data_ and size_ must be consistent");
  aligned_free(data_);
}

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IoBuffer() [3/4]

IoBuffer::IoBuffer ( const IoBuffer &  )

delete

IoBuffer() [4/4]

IoBuffer::IoBuffer

(

IoBuffer &&

other

)

Definition at line 29 of file io_buffer.cpp.

                                   : data_(other.data_), size_(other.size_) {
  other.data_ = nullptr;
  other.size_ = 0;
}

Member Function Documentation

GetBuffer() [1/2]

auto IoBuffer::GetBuffer

(

)

-> std::span<uint8_t>

获取缓冲区数据与大小

Returns

std::span<uint8_t> 缓冲区数据的可变视图

Precondition

None

Postcondition

返回指向缓冲区数据的 span

Definition at line 52 of file io_buffer.cpp.

{ return {data_, size_}; }

GetBuffer() [2/2]

auto IoBuffer::GetBuffer

(

)

const -> std::span<const uint8_t>

获取缓冲区数据与大小 (只读)

Returns

std::span<const uint8_t> 缓冲区数据的只读视图

Precondition

None

Postcondition

返回指向缓冲区数据的常量 span

Definition at line 48 of file io_buffer.cpp.

                                                         {
  return {data_, size_};
}

IsValid()

auto IoBuffer::IsValid

(

)

const -> bool

检查缓冲区是否有效

Returns

bool 有效则返回 true

Precondition

None

Postcondition

返回缓冲区是否已分配且有效的状态

Definition at line 54 of file io_buffer.cpp.

{ return data_ != nullptr; }

operator=() [1/2]

auto IoBuffer::operator= ( const IoBuffer &  ) -> IoBuffer &=delete

delete

operator=() [2/2]

auto IoBuffer::operator= ( IoBuffer &&  other ) -> IoBuffer&

noexcept

Definition at line 34 of file io_buffer.cpp.

                                                               {
  assert(this != &other && "Self-move assignment is not allowed");
 
  if (data_ != nullptr) {
    aligned_free(data_);
  }
  data_ = other.data_;
  size_ = other.size_;
  other.data_ = nullptr;
  other.size_ = 0;
 
  return *this;
}

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ToDmaRegion()

auto IoBuffer::ToDmaRegion

(

VirtToPhysFunc

v2p = IdentityVirtToPhys

)

const -> DmaRegion

创建此缓冲区的 DmaRegion 视图

Parameters

v2p	地址转换函数（默认：恒等映射）

Returns

描述此缓冲区内存的 DmaRegion

Precondition

IsValid() == true

Postcondition

返回的 DmaRegion 不拥有内存所有权

Definition at line 56 of file io_buffer.cpp.

                                                                {
  return DmaRegion{
      .virt = data_,
      .phys = v2p(reinterpret_cast<uintptr_t>(data_)),
      .size = size_,
  };
}

Member Data Documentation

data_

uint8_t* IoBuffer::data_ {nullptr}

private

缓冲区数据指针

Definition at line 150 of file io_buffer.hpp.

{nullptr};

kDefaultAlignment

constexpr size_t IoBuffer::kDefaultAlignment = 4096

staticconstexpr

IO 缓冲区的默认对齐大小（如页大小）

Definition at line 88 of file io_buffer.hpp.

size_

size_t IoBuffer::size_ {0}

private

缓冲区大小

Definition at line 152 of file io_buffer.hpp.

{0};

---

The documentation for this class was generated from the following files:

• /workspaces/SimpleKernel/src/include/io_buffer.hpp
• /workspaces/SimpleKernel/src/io_buffer.cpp
• /workspaces/SimpleKernel/tests/unit_test/mocks/io_buffer_mock.cpp