net: remove packet pool.

The pool was prone to deadlocks, especially due to having a single pool
for rx+tx. If the pool got full with rx'd packets it would deadlock because
processing a rx packet requires doing another allocation on the pool, for
the possibly tx'd response, before deallocating the rx'd packet.

This also allows Device impls to allocate the packet memory in a particular
RAM kind, if needed for example to do DMA.

The `Device` trait is now token-based, like smoltcp's. In the end, this
is better because it allows callers to manage memory however they want (including
with a pool if they want to).

1 files changed, 0 insertions, 107 deletions

diff --git a/embassy-net/src/packet_pool.rs b/embassy-net/src/packet_pool.rs
deleted file mode 100644
index cb8a1316c..000000000
--- a/embassy-net/src/packet_pool.rs
+++ /dev/null
@@ -1,107 +0,0 @@
-use core::ops::{Deref, DerefMut, Range};
-
-use as_slice::{AsMutSlice, AsSlice};
-use atomic_pool::{pool, Box};
-
-pub const MTU: usize = 1516;
-
-#[cfg(feature = "pool-4")]
-pub const PACKET_POOL_SIZE: usize = 4;
-
-#[cfg(feature = "pool-8")]
-pub const PACKET_POOL_SIZE: usize = 8;
-
-#[cfg(feature = "pool-16")]
-pub const PACKET_POOL_SIZE: usize = 16;
-
-#[cfg(feature = "pool-32")]
-pub const PACKET_POOL_SIZE: usize = 32;
-
-#[cfg(feature = "pool-64")]
-pub const PACKET_POOL_SIZE: usize = 64;
-
-#[cfg(feature = "pool-128")]
-pub const PACKET_POOL_SIZE: usize = 128;
-
-pool!(pub PacketPool: [Packet; PACKET_POOL_SIZE]);
-pub type PacketBox = Box<PacketPool>;
-
-#[repr(align(4))]
-pub struct Packet(pub [u8; MTU]);
-
-impl Packet {
-    pub const fn new() -> Self {
-        Self([0; MTU])
-    }
-}
-
-pub trait PacketBoxExt {
-    fn slice(self, range: Range<usize>) -> PacketBuf;
-}
-
-impl PacketBoxExt for PacketBox {
-    fn slice(self, range: Range<usize>) -> PacketBuf {
-        PacketBuf { packet: self, range }
-    }
-}
-
-impl AsSlice for Packet {
-    type Element = u8;
-
-    fn as_slice(&self) -> &[Self::Element] {
-        &self.deref()[..]
-    }
-}
-
-impl AsMutSlice for Packet {
-    fn as_mut_slice(&mut self) -> &mut [Self::Element] {
-        &mut self.deref_mut()[..]
-    }
-}
-
-impl Deref for Packet {
-    type Target = [u8; MTU];
-
-    fn deref(&self) -> &[u8; MTU] {
-        &self.0
-    }
-}
-
-impl DerefMut for Packet {
-    fn deref_mut(&mut self) -> &mut [u8; MTU] {
-        &mut self.0
-    }
-}
-
-pub struct PacketBuf {
-    packet: PacketBox,
-    range: Range<usize>,
-}
-
-impl AsSlice for PacketBuf {
-    type Element = u8;
-
-    fn as_slice(&self) -> &[Self::Element] {
-        &self.packet[self.range.clone()]
-    }
-}
-
-impl AsMutSlice for PacketBuf {
-    fn as_mut_slice(&mut self) -> &mut [Self::Element] {
-        &mut self.packet[self.range.clone()]
-    }
-}
-
-impl Deref for PacketBuf {
-    type Target = [u8];
-
-    fn deref(&self) -> &[u8] {
-        &self.packet[self.range.clone()]
-    }
-}
-
-impl DerefMut for PacketBuf {
-    fn deref_mut(&mut self) -> &mut [u8] {
-        &mut self.packet[self.range.clone()]
-    }
-}