netstack3_device/
state.rs

1// Copyright 2021 The Fuchsia Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5//! State maintained by the device layer.
6
7use alloc::sync::Arc;
8use core::fmt::Debug;
9
10use lock_order::lock::{OrderedLockAccess, OrderedLockRef};
11use net_types::ip::{Ipv4, Ipv6};
12use netstack3_base::sync::{RwLock, WeakRc};
13use netstack3_base::{
14    CoreTimerContext, Device, DeviceIdContext, Inspectable, TimerContext, WeakDeviceIdentifier,
15};
16use netstack3_ip::RawMetric;
17use netstack3_ip::device::{DualStackIpDeviceState, IpDeviceTimerId};
18
19use crate::internal::base::{DeviceCounters, DeviceLayerTypes, OriginTracker};
20use crate::internal::queue::DeviceBufferSpec;
21use crate::internal::socket::HeldDeviceSockets;
22
23/// Provides the specifications for device state held by [`BaseDeviceId`] in
24/// [`BaseDeviceState`].
25pub trait DeviceStateSpec: Device + Sized + Send + Sync + 'static {
26    /// The device state.
27    type State<BT: DeviceLayerTypes>: Send + Sync;
28    /// The external (bindings) state.
29    type External<BT: DeviceLayerTypes>: Send + Sync;
30    /// Properties given to device creation.
31    type CreationProperties: Debug;
32    /// Device-specific counters.
33    type Counters: Inspectable;
34    /// The timer identifier required by this device state.
35    type TimerId<D: WeakDeviceIdentifier>;
36
37    /// Creates a new device state from the given properties.
38    fn new_device_state<
39        CC: CoreTimerContext<Self::TimerId<CC::WeakDeviceId>, BC> + DeviceIdContext<Self>,
40        BC: DeviceLayerTypes + TimerContext,
41    >(
42        bindings_ctx: &mut BC,
43        self_id: CC::WeakDeviceId,
44        properties: Self::CreationProperties,
45        tx_allocator: <Self as DeviceBufferSpec<BC>>::TxAllocator,
46    ) -> Self::State<BC>
47    where
48        Self: DeviceBufferSpec<BC>;
49
50    /// Marker for loopback devices.
51    const IS_LOOPBACK: bool;
52    /// Marker used to print debug information for device identifiers.
53    const DEBUG_TYPE: &'static str;
54}
55
56/// Groups state kept by weak device references.
57///
58/// A weak device reference must be able to carry the bindings identifier
59/// infallibly. The `WeakCookie` is kept inside [`BaseDeviceState`] in an `Arc`
60/// to group all the information that is cloned out to support weak device
61/// references.
62pub(crate) struct WeakCookie<T: DeviceStateSpec, BT: DeviceLayerTypes> {
63    pub(crate) bindings_id: BT::DeviceIdentifier,
64    pub(crate) weak_ref: WeakRc<BaseDeviceState<T, BT>>,
65}
66
67pub(crate) struct BaseDeviceState<T: DeviceStateSpec, BT: DeviceLayerTypes> {
68    pub(crate) ip: IpLinkDeviceState<T, BT>,
69    pub(crate) external_state: T::External<BT>,
70    pub(crate) weak_cookie: Arc<WeakCookie<T, BT>>,
71}
72
73/// A convenience wrapper around `IpLinkDeviceStateInner` that uses
74/// `DeviceStateSpec` to extract the link state type and make type signatures
75/// shorter.
76pub type IpLinkDeviceState<T, BT> = IpLinkDeviceStateInner<<T as DeviceStateSpec>::State<BT>, BT>;
77
78/// State for a link-device that is also an IP device.
79///
80/// `D` is the link-specific state.
81pub struct IpLinkDeviceStateInner<T, BT: DeviceLayerTypes> {
82    /// The device's IP state.
83    pub ip: DualStackIpDeviceState<BT>,
84    /// The device's link state.
85    pub link: T,
86    pub(crate) origin: OriginTracker,
87    pub(super) sockets: RwLock<HeldDeviceSockets<BT>>,
88    /// Common device counters.
89    pub counters: DeviceCounters,
90}
91
92impl<T, BC: DeviceLayerTypes + TimerContext> IpLinkDeviceStateInner<T, BC> {
93    /// Create a new `IpLinkDeviceState` with a link-specific state `link`.
94    pub fn new<
95        D: WeakDeviceIdentifier,
96        CC: CoreTimerContext<IpDeviceTimerId<Ipv6, D, BC>, BC>
97            + CoreTimerContext<IpDeviceTimerId<Ipv4, D, BC>, BC>,
98    >(
99        bindings_ctx: &mut BC,
100        device_id: D,
101        link: T,
102        metric: RawMetric,
103        origin: OriginTracker,
104    ) -> Self {
105        Self {
106            ip: DualStackIpDeviceState::new::<D, CC>(bindings_ctx, device_id, metric),
107            link,
108            origin,
109            sockets: RwLock::new(HeldDeviceSockets::default()),
110            counters: DeviceCounters::default(),
111        }
112    }
113}
114
115impl<T, BT: DeviceLayerTypes> AsRef<DualStackIpDeviceState<BT>> for IpLinkDeviceStateInner<T, BT> {
116    fn as_ref(&self) -> &DualStackIpDeviceState<BT> {
117        &self.ip
118    }
119}
120
121impl<T, BT: DeviceLayerTypes> OrderedLockAccess<HeldDeviceSockets<BT>>
122    for IpLinkDeviceStateInner<T, BT>
123{
124    type Lock = RwLock<HeldDeviceSockets<BT>>;
125    fn ordered_lock_access(&self) -> OrderedLockRef<'_, Self::Lock> {
126        OrderedLockRef::new(&self.sockets)
127    }
128}
netstack3_device/state.rs

netstack3_device/
state.rs
