Merge pull request #1149 from hermit-os/virtio-def

feat: add `virtio-def` crate for virtio definitions

Cargo.toml

@@ -71,6 +71,7 @@ shell = ["simple-shell"]
 
 [dependencies]
 hermit-macro = { path = "hermit-macro" }
+virtio-def = { path = "virtio-def" }
 ahash = { version = "0.8", default-features = false }
 align-address = "0.1"
 bit_field = "0.10"
@@ -154,8 +155,13 @@ llvm-tools = "0.1"
 [workspace]
 members = [
     "hermit-macro",
+    "virtio-def",
 	"xtask",
 ]
 exclude = [
 	"hermit-builtins",
 ]
+
+[patch.crates-io]
+# We need https://github.com/rust-osdev/volatile/pull/61
+volatile = { git = "https://github.com/rust-osdev/volatile.git" }

src/drivers/virtio/mod.rs

@@ -165,45 +165,3 @@ pub mod features {
 		}
 	}
 }
-
-/// A module containing virtios device specfific information.
-pub mod device {
-	/// An enum of the device's status field interpretations.
-	#[allow(dead_code, non_camel_case_types, clippy::upper_case_acronyms)]
-	#[derive(Clone, Copy, Debug)]
-	#[repr(u8)]
-	pub enum Status {
-		ACKNOWLEDGE = 1,
-		DRIVER = 2,
-		DRIVER_OK = 4,
-		FEATURES_OK = 8,
-		DEVICE_NEEDS_RESET = 64,
-		FAILED = 128,
-	}
-
-	impl From<Status> for u8 {
-		fn from(stat: Status) -> Self {
-			match stat {
-				Status::ACKNOWLEDGE => 1,
-				Status::DRIVER => 2,
-				Status::DRIVER_OK => 4,
-				Status::FEATURES_OK => 8,
-				Status::DEVICE_NEEDS_RESET => 64,
-				Status::FAILED => 128,
-			}
-		}
-	}
-
-	impl From<Status> for u32 {
-		fn from(stat: Status) -> Self {
-			match stat {
-				Status::ACKNOWLEDGE => 1,
-				Status::DRIVER => 2,
-				Status::DRIVER_OK => 4,
-				Status::FEATURES_OK => 8,
-				Status::DEVICE_NEEDS_RESET => 64,
-				Status::FAILED => 128,
-			}
-		}
-	}
-}

src/drivers/virtio/transport/mmio.rs

@@ -7,6 +7,8 @@ use core::ptr;
 use core::ptr::{read_volatile, write_volatile};
 use core::sync::atomic::{fence, Ordering};
 
+use virtio_def::DeviceStatus;
+
 #[cfg(any(feature = "tcp", feature = "udp"))]
 use crate::arch::kernel::interrupts::*;
 use crate::arch::mm::PhysAddr;
@@ -15,7 +17,6 @@ use crate::drivers::error::DriverError;
 use crate::drivers::net::network_irqhandler;
 #[cfg(any(feature = "tcp", feature = "udp"))]
 use crate::drivers::net::virtio_net::VirtioNetDriver;
-use crate::drivers::virtio::device;
 use crate::drivers::virtio::error::VirtioError;
 
 /// Virtio device ID's
@@ -141,13 +142,13 @@ impl ComCfg {
 
 	/// Returns the device status field.
 	pub fn dev_status(&self) -> u8 {
-		unsafe { read_volatile(&self.com_cfg.status).try_into().unwrap() }
+		unsafe { read_volatile(&self.com_cfg.status).bits() }
 	}
 
 	/// Resets the device status field to zero.
 	pub fn reset_dev(&mut self) {
 		unsafe {
-			write_volatile(&mut self.com_cfg.status, 0u32);
+			write_volatile(&mut self.com_cfg.status, DeviceStatus::empty());
 		}
 	}
 
@@ -156,7 +157,7 @@ impl ComCfg {
 	/// A driver MAY use the device again after a proper reset of the device.
 	pub fn set_failed(&mut self) {
 		unsafe {
-			write_volatile(&mut self.com_cfg.status, u32::from(device::Status::FAILED));
+			write_volatile(&mut self.com_cfg.status, DeviceStatus::FAILED);
 		}
 	}
 
@@ -165,10 +166,7 @@ impl ComCfg {
 	pub fn ack_dev(&mut self) {
 		unsafe {
 			let status = read_volatile(&self.com_cfg.status);
-			write_volatile(
-				&mut self.com_cfg.status,
-				status | u32::from(device::Status::ACKNOWLEDGE),
-			);
+			write_volatile(&mut self.com_cfg.status, status | DeviceStatus::ACKNOWLEDGE);
 		}
 	}
 
@@ -177,10 +175,7 @@ impl ComCfg {
 	pub fn set_drv(&mut self) {
 		unsafe {
 			let status = read_volatile(&self.com_cfg.status);
-			write_volatile(
-				&mut self.com_cfg.status,
-				status | u32::from(device::Status::DRIVER),
-			);
+			write_volatile(&mut self.com_cfg.status, status | DeviceStatus::DRIVER);
 		}
 	}
 
@@ -190,10 +185,7 @@ impl ComCfg {
 	pub fn features_ok(&mut self) {
 		unsafe {
 			let status = read_volatile(&self.com_cfg.status);
-			write_volatile(
-				&mut self.com_cfg.status,
-				status | u32::from(device::Status::FEATURES_OK),
-			);
+			write_volatile(&mut self.com_cfg.status, status | DeviceStatus::FEATURES_OK);
 		}
 	}
 
@@ -206,8 +198,7 @@ impl ComCfg {
 	pub fn check_features(&self) -> bool {
 		unsafe {
 			let status = read_volatile(&self.com_cfg.status);
-			status & u32::from(device::Status::FEATURES_OK)
-				== u32::from(device::Status::FEATURES_OK)
+			status.contains(DeviceStatus::FEATURES_OK)
 		}
 	}
 
@@ -217,10 +208,7 @@ impl ComCfg {
 	pub fn drv_ok(&mut self) {
 		unsafe {
 			let status = read_volatile(&self.com_cfg.status);
-			write_volatile(
-				&mut self.com_cfg.status,
-				status | u32::from(device::Status::DRIVER_OK),
-			);
+			write_volatile(&mut self.com_cfg.status, status | DeviceStatus::DRIVER_OK);
 		}
 	}
 
@@ -440,8 +428,8 @@ pub struct MmioRegisterLayout {
 	interrupt_ack: u32,
 	_reserved4: [u32; 2],
 
-	status: u32,
-	_reserved5: [u32; 3],
+	status: DeviceStatus,
+	_reserved5: [u8; 15],
 
 	queue_desc_low: u32,  // non-legacy only
 	queue_desc_high: u32, // non-legacy only