asterinas/kernel/src/syscall/sendmmsg.rs

81 lines
2.1 KiB
Rust

// SPDX-License-Identifier: MPL-2.0
use ostd::mm::VmIo;
use crate::{
fs::file_table::FileDesc,
net::socket::{Socket, util::SendRecvFlags},
prelude::*,
syscall::{SyscallReturn, sendmsg::send_one_message},
util::net::CUserMsgHdr,
};
pub fn sys_sendmmsg(
sockfd: FileDesc,
mmsghdrs_addr: Vaddr,
count: usize,
flags: i32,
ctx: &Context,
) -> Result<SyscallReturn> {
let flags = SendRecvFlags::from_bits(flags)
.ok_or_else(|| Error::with_message(Errno::EINVAL, "invalid send recv flags"))?;
debug!(
"sockfd = {}, mmsghdrs = {:#x}, count = {}, flags = {:?}",
sockfd, mmsghdrs_addr, count, flags
);
if !flags.is_empty() {
warn!("sendmmsg flags {:?} are not supported", flags);
}
let file = {
// Reading control messages may access the file table,
// so we have to clone the file and drop the file table reference here.
let file_table = ctx.thread_local.borrow_file_table();
let file_table_locked = file_table.unwrap().read();
file_table_locked.get_file(sockfd)?.clone()
};
let socket = file.as_socket_or_err()?;
let mut sent_msgs = 0;
match send_mmsg_hdrs(socket, mmsghdrs_addr, count, flags, &mut sent_msgs, ctx) {
// Only return error if no packets are sent successfully.
Err(e) if sent_msgs == 0 => Err(e),
_ => Ok(SyscallReturn::Return(sent_msgs as _)),
}
}
#[repr(C)]
#[padding_struct]
#[derive(Debug, Clone, Copy, Pod)]
struct CMmsgHdr {
msg_hdr: CUserMsgHdr,
msg_len: u32,
}
fn send_mmsg_hdrs(
socket: &dyn Socket,
mmsghdrs_addr: Vaddr,
count: usize,
flags: SendRecvFlags,
sent_msgs: &mut usize,
ctx: &Context,
) -> Result<()> {
let user_space = ctx.user_space();
for i in 0..count {
let addr = mmsghdrs_addr + size_of::<CMmsgHdr>() * i;
let mut mmsghdr = user_space.read_val::<CMmsgHdr>(addr)?;
let sent_bytes = send_one_message(socket, &mmsghdr.msg_hdr, &user_space, flags)?;
mmsghdr.msg_len = sent_bytes as u32;
user_space.write_val(addr, &mmsghdr)?;
*sent_msgs += 1;
}
Ok(())
}