net, server: put tcp storage on stack

src/main.rs

@@ -100,9 +100,8 @@ fn main() -> ! {
     timer::setup(cp.SYST, clocks);
 
     info!("Net startup");
-    net::run(&mut cp.NVIC, dp.ETHERNET_MAC, dp.ETHERNET_DMA, |net| {
+    net::run(&mut cp.NVIC, dp.ETHERNET_MAC, dp.ETHERNET_DMA, |iface| {
-        let mut server = Server::new(net);
+        Server::run(iface, |server| {
-
             let mut last_output = 0_u32;
             loop {
                 led_green.on();
@@ -135,5 +134,8 @@ fn main() -> ! {
                 });
                 led_red.off();
             }
-    })
+        });
+    });
+
+    unimplemented!()
 }

src/net.rs

@@ -7,14 +7,15 @@ use bare_metal::CriticalSection;
 use stm32f4xx_hal::{
     stm32::{interrupt, Peripherals, NVIC, ETHERNET_MAC, ETHERNET_DMA},
 };
-use smoltcp::time::Instant;
 use smoltcp::wire::{EthernetAddress, IpAddress, IpCidr};
 use smoltcp::iface::{NeighborCache, EthernetInterfaceBuilder, EthernetInterface};
-use smoltcp::socket::SocketSet;
 use stm32_eth::{Eth, RingEntry, RxDescriptor, TxDescriptor};
 
-// TODO: ram regions
+/// Not on the stack so that stack can be placed in CCMRAM (which the
+/// ethernet peripheral cannot access)
 static mut RX_RING: Option<[RingEntry<RxDescriptor>; 8]> = None;
+/// Not on the stack so that stack can be placed in CCMRAM (which the
+/// ethernet peripheral cannot access)
 static mut TX_RING: Option<[RingEntry<TxDescriptor>; 2]> = None;
 
 // TODO: generate one from device id
@@ -22,9 +23,9 @@ const SRC_MAC: [u8; 6] = [0x00, 0x00, 0xDE, 0xAD, 0xBE, 0xEF];
 
 static NET_PENDING: Mutex<RefCell<bool>> = Mutex::new(RefCell::new(false));
 
-pub fn run<F>(nvic: &mut NVIC, ethernet_mac: ETHERNET_MAC, ethernet_dma: ETHERNET_DMA, f: F) -> !
+pub fn run<F>(nvic: &mut NVIC, ethernet_mac: ETHERNET_MAC, ethernet_dma: ETHERNET_DMA, f: F)
 where
-    F: FnOnce(&mut NetInterface) -> !
+    F: FnOnce(EthernetInterface<&mut stm32_eth::Eth<'static, 'static>>),
 {
     let rx_ring = unsafe {
         RX_RING.get_or_insert(Default::default())
@@ -49,37 +50,10 @@ where
         .neighbor_cache(neighbor_cache)
         .finalize();
 
-    let mut sockets_storage = [None, None, None, None];
+    f(iface);
-    let sockets = SocketSet::new(&mut sockets_storage[..]);
-
-    let mut net_iface = NetInterface {
-        iface,
-        sockets,
-    };
-    f(&mut net_iface);
 }
 
-pub struct NetInterface<'a> {
+/// Wake up from `wfi()`, clear interrupt flags,
-    iface: EthernetInterface<'a, 'a, 'a, &'a mut stm32_eth::Eth<'static, 'static>>,
-    sockets: SocketSet<'a, 'static, 'static>,
-}
-
-impl<'a> NetInterface<'a> {
-    /// Passes the boolean that indicates any sockets change.
-    pub fn poll(&mut self, now: Instant) -> bool {
-        // TODO: clear pending flag
-
-        self.iface.poll(&mut self.sockets, now)
-            .ok()
-            .unwrap_or(false)
-    }
-
-    pub fn sockets(&mut self) -> &mut SocketSet<'a, 'static, 'static> {
-        &mut self.sockets
-    }
-}
-
-/// Wwake up from `wfi()`, clear interrupt flags,
 /// and TODO: set pending flag
 #[interrupt]
 fn ETH() {

src/server.rs

@@ -1,63 +1,88 @@
 use core::fmt;
 use core::mem::uninitialized;
 use smoltcp::{
-    socket::{SocketHandle, TcpSocket, TcpSocketBuffer},
+    iface::EthernetInterface,
+    socket::{SocketSet, SocketHandle, TcpSocket, TcpSocketBuffer},
     time::Instant,
 };
 
-use crate::net::NetInterface;
 
 const TCP_PORT: u16 = 23;
-const SOCKET_COUNT: usize = 4;
+const SOCKET_COUNT: usize = 8;
-const SOCKET_BUFFER_SIZE: usize = 2048;
-const SOCKET_BUFFERS_LENGTH: usize = 2 * SOCKET_COUNT * SOCKET_BUFFER_SIZE;
 
-static mut SOCKET_BUFFERS: [u8; SOCKET_BUFFERS_LENGTH] = [0u8; SOCKET_BUFFERS_LENGTH];
+const TCP_RX_BUFFER_SIZE: usize = 2048;
+const TCP_TX_BUFFER_SIZE: usize = 2048;
 
-fn get_socket_buffers(i: usize) -> (&'static mut [u8], &'static mut [u8]) {
+macro_rules! create_socket_storage {
-    let offset1 = 2 * i * SOCKET_BUFFER_SIZE;
+    ($rx_storage:ident, $tx_storage:ident) => (
-    let offset2 = offset1 + SOCKET_BUFFER_SIZE;
+        let mut $rx_storage = [0; TCP_RX_BUFFER_SIZE];
-    let offset3 = offset2 + SOCKET_BUFFER_SIZE;
+        let mut $tx_storage = [0; TCP_TX_BUFFER_SIZE];
-    unsafe {
+    )
-        (&mut SOCKET_BUFFERS[offset1..offset2],
-         &mut SOCKET_BUFFERS[offset2..offset3])
 }
+
+macro_rules! create_socket {
+    ($set:ident, $rx_storage:ident, $tx_storage:ident, $target:expr) => (
+        let tcp_rx_buffer = TcpSocketBuffer::new(&mut $rx_storage[..]);
+        let tcp_tx_buffer = TcpSocketBuffer::new(&mut $tx_storage[..]);
+        let tcp_socket = TcpSocket::new(tcp_rx_buffer, tcp_tx_buffer);
+        $target = $set.add(tcp_socket);
+    )
 }
 
 /// Contains a number of server sockets that get all sent the same
 /// data (through `fmt::Write`).
-pub struct Server<'a, 's> {
+pub struct Server<'a, 'b> {
+    net: EthernetInterface<'a, 'a, 'a, &'a mut stm32_eth::Eth<'static, 'static>>,
+    sockets: SocketSet<'b, 'b, 'static>,
     handles: [SocketHandle; SOCKET_COUNT],
-    net: &'s mut NetInterface<'a>,
 }
 
-impl<'a, 's> Server<'a, 's> {
+impl<'a, 'b> Server<'a, 'b> {
-    pub fn new(net: &'s mut NetInterface<'a>) -> Self {
+    pub fn run<F>(net: EthernetInterface<'a, 'a, 'a, &'a mut stm32_eth::Eth<'static, 'static>>, f: F)
+    where
+        F: FnOnce(&mut Server<'a, '_>),
+    {
+        create_socket_storage!(tcp_rx_storage0, tcp_tx_storage0);
+        create_socket_storage!(tcp_rx_storage1, tcp_tx_storage1);
+        create_socket_storage!(tcp_rx_storage2, tcp_tx_storage2);
+        create_socket_storage!(tcp_rx_storage3, tcp_tx_storage3);
+        create_socket_storage!(tcp_rx_storage4, tcp_tx_storage4);
+        create_socket_storage!(tcp_rx_storage5, tcp_tx_storage5);
+        create_socket_storage!(tcp_rx_storage6, tcp_tx_storage6);
+        create_socket_storage!(tcp_rx_storage7, tcp_tx_storage7);
+
+        let mut sockets_storage = [
+            None, None, None, None,
+            None, None, None, None
+        ];
+        let mut sockets = SocketSet::new(&mut sockets_storage[..]);
+        let mut handles: [SocketHandle; SOCKET_COUNT] = unsafe { uninitialized() };
+        create_socket!(sockets, tcp_rx_storage0, tcp_tx_storage0, handles[0]);
+        create_socket!(sockets, tcp_rx_storage1, tcp_tx_storage1, handles[1]);
+        create_socket!(sockets, tcp_rx_storage2, tcp_tx_storage2, handles[2]);
+        create_socket!(sockets, tcp_rx_storage3, tcp_tx_storage3, handles[3]);
+        create_socket!(sockets, tcp_rx_storage4, tcp_tx_storage4, handles[4]);
+        create_socket!(sockets, tcp_rx_storage5, tcp_tx_storage5, handles[5]);
+        create_socket!(sockets, tcp_rx_storage6, tcp_tx_storage6, handles[6]);
+        create_socket!(sockets, tcp_rx_storage7, tcp_tx_storage7, handles[7]);
+
         let mut server = Server {
-            handles: unsafe { uninitialized() },
+            handles,
+            sockets,
             net,
         };
-
+        f(&mut server);
-        for i in 0..SOCKET_COUNT {
-            let buffers = get_socket_buffers(i);
-            let server_socket = TcpSocket::new(
-                TcpSocketBuffer::new(&mut buffers.0[..]),
-                TcpSocketBuffer::new(&mut buffers.1[..])
-            );
-            server.handles[i] = server.net.sockets().add(server_socket);
-        }
-
-        server
     }
 
     pub fn poll(&mut self, now: Instant) {
-        let activity = self.net.poll(now);
+        let activity = self.net.poll(&mut self.sockets, now)
+            .unwrap_or(true);
         if ! activity {
             return;
         }
 
         for handle in &self.handles {
-            let mut socket = self.net.sockets().get::<TcpSocket>(*handle);
+            let mut socket = self.sockets.get::<TcpSocket>(*handle);
             if ! socket.is_open() {
                 socket.listen(TCP_PORT)
                     .unwrap();
@@ -70,7 +95,7 @@ impl<'a, 's> fmt::Write for Server<'a, 's> {
     /// Write to all connected clients
     fn write_str(&mut self, slice: &str) -> fmt::Result {
         for handle in &self.handles {
-            let mut socket = self.net.sockets().get::<TcpSocket>(*handle);
+            let mut socket = self.sockets.get::<TcpSocket>(*handle);
             if socket.can_send() {
                 // Ignore errors, proceed with next client
                 let _ = socket.write_str(slice);