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

netstack3_device/
state.rs
