virtio::DeviceInitializer< TransportImpl > Class Template Reference

Virtio 设备初始化器 More...

#include <device_initializer.hpp>

Collaboration diagram for virtio::DeviceInitializer< TransportImpl >:

Public Member Functions
auto	Init (uint64_t driver_features) -> Expected< uint64_t >
	执行 virtio 设备初始化序列
auto	SetupQueue (uint32_t queue_idx, uint64_t desc_phys, uint64_t avail_phys, uint64_t used_phys, uint32_t queue_size) -> Expected< void >
	配置并激活指定的 virtqueue
auto	Activate () -> Expected< void >
	激活设备，开始正常运行
auto	transport () -> TransportImpl &
	获取底层传输层引用
auto	transport () const -> const TransportImpl &
构造/析构函数
	DeviceInitializer (TransportImpl &transport)
	构造函数
	DeviceInitializer ()=delete
	DeviceInitializer (const DeviceInitializer &)=delete
	DeviceInitializer (DeviceInitializer &&)=delete
auto	operator= (const DeviceInitializer &) -> DeviceInitializer &=delete
auto	operator= (DeviceInitializer &&) -> DeviceInitializer &=delete
	~DeviceInitializer ()=default

Private Attributes
TransportImpl &	transport_
	底层传输层引用

Detailed Description

template<TransportConcept TransportImpl>
class virtio::DeviceInitializer< TransportImpl >

Virtio 设备初始化器

负责编排 virtio 设备的初始化流程，独立于底层传输机制（MMIO、PCI 等）。 实现 virtio 规范定义的标准初始化序列。

主要职责：

• 执行完整的设备初始化序列（特性协商、状态设置等）
• 配置和激活 virtqueue
• 提供设备初始化流程的统一抽象

使用示例：

MmioTransport<> transport(base_addr);
DeviceInitializer<> initializer(transport);
 
// 初始化设备并协商特性
auto features_result = initializer.Init(my_driver_features);
if (!features_result) { handle_error(); }
 
// 配置队列
initializer.SetupQueue(0, desc_phys, avail_phys, used_phys, queue_size);
 
// 激活设备
initializer.Activate();

Template Parameters

TransportImpl

具体传输层类型（如 MmioTransport）

See also

virtio-v1.2#3.1.1 Driver Requirements: Device Initialization

Definition at line 46 of file device_initializer.hpp.

Constructor & Destructor Documentation

DeviceInitializer() [1/4]

template<TransportConcept TransportImpl>

virtio::DeviceInitializer< TransportImpl >::DeviceInitializer ( TransportImpl &  transport )

inlineexplicit

构造函数

Parameters

transport

传输层引用（必须在 DeviceInitializer 生命周期内保持有效）

Precondition

transport.IsValid() == true

Definition at line 193 of file device_initializer.hpp.

      : transport_(transport) {}

DeviceInitializer() [2/4]

template<TransportConcept TransportImpl>

virtio::DeviceInitializer< TransportImpl >::DeviceInitializer ( )

delete

DeviceInitializer() [3/4]

template<TransportConcept TransportImpl>

virtio::DeviceInitializer< TransportImpl >::DeviceInitializer ( const DeviceInitializer< TransportImpl > &  )

delete

DeviceInitializer() [4/4]

template<TransportConcept TransportImpl>

virtio::DeviceInitializer< TransportImpl >::DeviceInitializer ( DeviceInitializer< TransportImpl > &&  )

delete

~DeviceInitializer()

template<TransportConcept TransportImpl>

virtio::DeviceInitializer< TransportImpl >::~DeviceInitializer ( )

default

Member Function Documentation

Activate()

template<TransportConcept TransportImpl>

auto virtio::DeviceInitializer< TransportImpl >::Activate ( ) -> Expected<void>

inline

激活设备，开始正常运行

设置 DRIVER_OK 状态位，完成设备初始化流程（步骤 8）。 必须在所有队列配置完成后调用。 调用后设备开始正常运行，可以处理队列中的请求。

Returns

成功或失败

Precondition

transport_.IsValid() == true

Init() 已成功调用

所有需要的队列已通过 SetupQueue() 配置

See also

virtio-v1.2#3.1.1 Driver Requirements: Device Initialization

Definition at line 153 of file device_initializer.hpp.

                                                  {
    if (!transport_.IsValid()) {
      return std::unexpected(Error{ErrorCode::kTransportNotInitialized});
    }
 
    uint32_t current_status = transport_.GetStatus();
    transport_.SetStatus(
        current_status |
        std::to_underlying(Transport::DeviceStatus::kDriverOk));
 
    uint32_t new_status = transport_.GetStatus();
    if ((new_status &
         std::to_underlying(Transport::DeviceStatus::kDeviceNeedsReset)) != 0) {
      return std::unexpected(Error{ErrorCode::kDeviceError});
    }
 
    return {};
  }

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Init()

template<TransportConcept TransportImpl>

auto virtio::DeviceInitializer< TransportImpl >::Init ( uint64_t  driver_features ) -> Expected<uint64_t>

inline

执行 virtio 设备初始化序列

完整执行设备初始化流程（步骤 1-6）：

1. 重置设备（写入 0 到 status 寄存器）
2. 设置 ACKNOWLEDGE 状态位（识别为 virtio 设备）
3. 设置 DRIVER 状态位（驱动程序知道如何驱动）
4. 读取设备特性，与 driver_features 取交集后写回
5. 设置 FEATURES_OK 状态位
6. 重新读取验证 FEATURES_OK 是否仍被设置（设备可能拒绝某些特性组合）

Parameters

driver_features

驱动程序希望启用的特性位（将与设备特性取交集）

Returns

成功时返回实际协商后的特性位；失败返回错误

Precondition

transport_.IsValid() == true（传输层已成功初始化）

Postcondition

初始化成功后，调用者还需配置队列并调用 Activate() 完成激活

See also

virtio-v1.2#3.1.1 Driver Requirements: Device Initialization

Definition at line 65 of file device_initializer.hpp.

                                                                          {
    if (!transport_.IsValid()) {
      return std::unexpected(Error{ErrorCode::kTransportNotInitialized});
    }
 
    transport_.Reset();
 
    transport_.SetStatus(
        std::to_underlying(Transport::DeviceStatus::kAcknowledge));
 
    transport_.SetStatus(
        std::to_underlying(Transport::DeviceStatus::kAcknowledge) |
        std::to_underlying(Transport::DeviceStatus::kDriver));
 
    uint64_t device_features = transport_.GetDeviceFeatures();
    uint64_t negotiated_features = device_features & driver_features;
 
    transport_.SetDriverFeatures(negotiated_features);
 
    transport_.SetStatus(
        std::to_underlying(Transport::DeviceStatus::kAcknowledge) |
        std::to_underlying(Transport::DeviceStatus::kDriver) |
        std::to_underlying(Transport::DeviceStatus::kFeaturesOk));
 
    uint32_t status = transport_.GetStatus();
    if ((status & std::to_underlying(Transport::DeviceStatus::kFeaturesOk)) ==
        0) {
      transport_.SetStatus(
          status | std::to_underlying(Transport::DeviceStatus::kFailed));
      return std::unexpected(Error{ErrorCode::kFeatureNegotiationFailed});
    }
 
    return negotiated_features;
  }

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operator=() [1/2]

template<TransportConcept TransportImpl>

auto virtio::DeviceInitializer< TransportImpl >::operator= ( const DeviceInitializer< TransportImpl > &  ) -> DeviceInitializer &=delete

delete

operator=() [2/2]

template<TransportConcept TransportImpl>

auto virtio::DeviceInitializer< TransportImpl >::operator= ( DeviceInitializer< TransportImpl > &&  ) -> DeviceInitializer &=delete

delete

SetupQueue()

template<TransportConcept TransportImpl>

auto virtio::DeviceInitializer< TransportImpl >::SetupQueue ( uint32_t  queue_idx, uint64_t  desc_phys, uint64_t  avail_phys, uint64_t  used_phys, uint32_t  queue_size  ) -> Expected<void>

inline

配置并激活指定的 virtqueue

设置 virtqueue 的物理地址和大小，然后标记为就绪（步骤 7 的一部分）。 必须在调用 Init() 之后、Activate() 之前完成。

Parameters

queue_idx	队列索引（从 0 开始）
desc_phys	描述符表的客户机物理地址（必须 16 字节对齐）
avail_phys	Available Ring 的客户机物理地址（必须 2 字节对齐）
used_phys	Used Ring 的客户机物理地址（必须 4 字节对齐）
queue_size	队列大小（必须 <= transport_.GetQueueNumMax()）

Returns

成功或失败

Precondition

transport_.IsValid() == true

Init() 已成功调用

See also

virtio-v1.2#3.1.1 Driver Requirements: Device Initialization

Definition at line 116 of file device_initializer.hpp.

                                                                       {
    if (!transport_.IsValid()) {
      return std::unexpected(Error{ErrorCode::kTransportNotInitialized});
    }
 
    uint32_t max_size = transport_.GetQueueNumMax(queue_idx);
    if (max_size == 0) {
      return std::unexpected(Error{ErrorCode::kQueueNotAvailable});
    }
    if (queue_size > max_size) {
      return std::unexpected(Error{ErrorCode::kQueueTooLarge});
    }
 
    transport_.SetQueueNum(queue_idx, queue_size);
    transport_.SetQueueDesc(queue_idx, desc_phys);
    transport_.SetQueueAvail(queue_idx, avail_phys);
    transport_.SetQueueUsed(queue_idx, used_phys);
    transport_.SetQueueReady(queue_idx, true);
 
    return {};
  }

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transport() [1/2]

template<TransportConcept TransportImpl>

auto virtio::DeviceInitializer< TransportImpl >::transport ( ) -> TransportImpl&

inline

获取底层传输层引用

允许访问底层传输层的其他功能（如读取配置空间、处理中断等）。

Returns

传输层的引用

Definition at line 179 of file device_initializer.hpp.

{ return transport_; }

transport() [2/2]

template<TransportConcept TransportImpl>

auto virtio::DeviceInitializer< TransportImpl >::transport ( ) const -> const TransportImpl&

inline

Definition at line 181 of file device_initializer.hpp.

                                                               {
    return transport_;
  }

Member Data Documentation

transport_

template<TransportConcept TransportImpl>

TransportImpl& virtio::DeviceInitializer< TransportImpl >::transport_

private

底层传输层引用

Definition at line 205 of file device_initializer.hpp.

---

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

• /workspaces/SimpleKernel/src/device/virtio/device/device_initializer.hpp