Struct SubmitEntry 

pub struct SubmitEntry {
    pub fd: i32,
    pub opcode: u8,
    pub flags: u16,
    pub user_data: u64,
    pub buf_ptr: Option<NonNull<u8>>,
    pub buf_len: u32,
    pub offset: u64,
    pub addr: Option<SockAddr>,
}

Submission queue entry 提交队列条目

Represents a single I/O operation to be submitted to the kernel. 表示要提交给内核的单个I/O操作。

Safety / 安全性

• buf_ptr must be valid for buf_len bytes if non-null
• The buffer must remain valid until the operation completes
• 如果非空，buf_ptr 必须对 buf_len 字节有效
• 缓冲区必须在操作完成前保持有效

Fields

fd: i32

File descriptor to operate on / 操作的文件描述符

opcode: u8

Operation opcode (READ, WRITE, etc.) / 操作操作码

flags: u16

Operation flags / 操作标志

user_data: u64

User data for completion correlation (opaque pointer) 用于完成关联的用户数据（不透明指针）

buf_ptr: Option<NonNull<u8>>

Buffer pointer / 缓冲区指针

buf_len: u32

Buffer length in bytes / 缓冲区长度（字节）

offset: u64

Offset for file operations / 文件操作的偏移量

addr: Option<SockAddr>

Address for connect/accept operations / 连接/接受操作的地址

Implementations

impl SubmitEntry

pub const fn new(fd: i32, opcode: u8, user_data: u64) -> Self

Create a new submission entry 创建新的提交条目

pub unsafe fn read(fd: i32, buf: *mut u8, buf_len: u32, user_data: u64) -> Self

Create a read operation entry 创建读操作条目

Safety / 安全性

buf must be valid for reads and remain valid until completion. buf 必须对读取有效并在完成前保持有效。

pub unsafe fn write( fd: i32, buf: *const u8, buf_len: u32, user_data: u64, ) -> Self

Create a write operation entry 创建写操作条目

Safety / 安全性

buf must be valid for reads and remain valid until completion. buf 必须对读取有效并在完成前保持有效。

pub unsafe fn with_buffer(self, buf: *mut u8, buf_len: u32) -> Self

Set the buffer for this operation 为此操作设置缓冲区

Safety / 安全性

buf must be valid for buf_len bytes. buf 必须对 buf_len 字节有效。

pub const fn with_offset(self, offset: u64) -> Self

Set the offset for file operations 为文件操作设置偏移量

pub const fn with_flags(self, flags: u16) -> Self

Set operation flags 设置操作标志

pub fn with_addr(self, addr: SockAddr) -> Self

Set socket address for connect/accept 为connect/accept设置套接字地址

pub unsafe fn buffer(&self) -> Option<&[u8]>

Get the buffer as a slice if available 如果可用，获取缓冲区的切片

Safety / 安全性

The returned slice is only valid if the buffer is still alive. 返回的切片仅在缓冲区仍然存活时有效。

pub unsafe fn buffer_mut(&self) -> Option<&mut [u8]>

Get the buffer as a mutable slice if available 如果可用，获取缓冲区的可变切片

Safety / 安全性

The returned slice is only valid if the buffer is still alive and mutable. 返回的切片仅在缓冲区仍然存活且可变时有效。

Trait Implementations

impl Clone for SubmitEntry

fn clone(&self) -> SubmitEntry

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SubmitEntry

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.