linux_io_uring/
register.rs

1use std::{ io, ptr };
2use std::os::unix::io::RawFd;
3use linux_io_uring_sys as sys;
4
5
6unsafe fn execute(fd: RawFd, opcode: libc::c_uint, arg: *const libc::c_void, len: libc::c_uint)
7    -> io::Result<()>
8{
9    if 0 == sys::io_uring_register(fd, opcode, arg, len) {
10       Ok(())
11    } else {
12       Err(io::Error::last_os_error())
13    }
14}
15
16/// Register files or user buffers for asynchronous I/O.
17#[allow(clippy::module_inception)]
18pub mod register {
19    use super::*;
20
21    #[non_exhaustive]
22    pub enum Target<'a> {
23        /// Register buffer,
24        /// then use the already registered buffer in
25        /// [ReadFixed](crate::opcode::ReadFixed) and [WriteFixed](crate::opcode::WriteFixed).
26        Buffers(&'a [libc::iovec]),
27
28        /// Register file descriptor,
29        /// then use the already registered fd in [Target::Fixed](crate::opcode::types::Target).
30        Files(&'a [RawFd]),
31
32        /// Register eventfd.
33        EventFd(RawFd),
34
35        #[cfg(feature = "unstable")]
36        FilesUpdate { offset: u32, fds: &'a [RawFd] }
37    }
38
39    impl Target<'_> {
40        pub(crate) unsafe fn execute(&self, fd: RawFd) -> io::Result<()> {
41            fn cast_ptr<T>(n: &T) -> *const T {
42                n as *const T
43            }
44
45            match self {
46                Target::Buffers(bufs) =>
47                    execute(fd, sys::IORING_REGISTER_BUFFERS, bufs.as_ptr() as *const _, bufs.len() as _),
48                Target::Files(fds) =>
49                    execute(fd, sys::IORING_REGISTER_FILES, fds.as_ptr() as *const _, fds.len() as _),
50                Target::EventFd(eventfd) =>
51                    execute(fd, sys::IORING_REGISTER_EVENTFD, cast_ptr::<RawFd>(eventfd) as *const _, 1),
52                #[cfg(feature = "unstable")]
53                Target::FilesUpdate { offset, fds } => {
54                    let fu = sys::io_uring_files_update {
55                        offset: *offset,
56                        fds: fds.as_ptr() as *mut _
57                    };
58                    let fu = &fu as *const sys::io_uring_files_update;
59
60                    execute(fd, sys::IORING_REGISTER_FILES_UPDATE, fu as *const _, fds.len() as _)
61                }
62            }
63        }
64    }
65}
66
67/// Unregister files or user buffers for asynchronous I/O.
68pub mod unregister {
69    use super::*;
70
71    #[non_exhaustive]
72    pub enum Target {
73        /// Unregister buffer.
74        Buffers,
75
76        /// Unregister file descriptor.
77        Files,
78
79        /// Unregister eventfd.
80        EventFd,
81    }
82
83    impl Target {
84        pub(crate) fn execute(&self, fd: RawFd) -> io::Result<()> {
85            let opcode = match self {
86                Target::Buffers => sys::IORING_UNREGISTER_BUFFERS,
87                Target::Files => sys::IORING_UNREGISTER_FILES,
88                Target::EventFd => sys::IORING_UNREGISTER_EVENTFD
89            };
90
91            unsafe {
92                execute(fd, opcode, ptr::null(), 0)
93            }
94        }
95    }
96}
linux_io_uring/register.rs

linux_io_uring/
register.rs
