devices: pvpanic: Add pci configuration for pvpanic device

Implemetion of BusDevice and PciDevice trait for pvpanic device.

Pvpanic device can be implemented as an ISA device or as a
PCI device, we choose PCI device for now.

Signed-off-by: Yi Wang <foxywang@tencent.com>

Cargo.lock

@@ -473,13 +473,16 @@ dependencies = [
  "arch",
  "bitflags 2.3.3",
  "byteorder",
+ "event_monitor",
  "hypervisor",
  "libc",
  "log",
+ "pci",
  "thiserror",
  "tpm",
  "versionize",
  "versionize_derive",
+ "vm-allocator",
  "vm-device",
  "vm-memory",
  "vm-migration",

devices/Cargo.toml

@@ -10,13 +10,16 @@ anyhow = "1.0.71"
 arch = { path = "../arch" }
 bitflags = "2.3.3"
 byteorder = "1.4.3"
+event_monitor = { path = "../event_monitor" }
 hypervisor = { path = "../hypervisor" }
 libc = "0.2.139"
 log = "0.4.17"
+pci = { path = "../pci" }
 thiserror = "1.0.40"
 tpm = { path = "../tpm" }
 versionize = "0.1.10"
 versionize_derive = "0.1.4"
+vm-allocator = { path = "../vm-allocator" }
 vm-device = { path = "../vm-device" }
 vm-memory = "0.11.0"
 vm-migration = { path = "../vm-migration" }

devices/src/lib.rs

@@ -10,6 +10,8 @@
 #[macro_use]
 extern crate bitflags;
 #[macro_use]
+extern crate event_monitor;
+#[macro_use]
 extern crate log;
 
 pub mod acpi;

devices/src/pvpanic.rs

@@ -3,22 +3,188 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
+use pci::{
+    BarReprogrammingParams, PciBarConfiguration, PciBarPrefetchable, PciBarRegionType,
+    PciClassCode, PciConfiguration, PciDevice, PciDeviceError, PciHeaderType, PciSubclass,
+};
+use std::any::Any;
+use std::result;
+use std::sync::{Arc, Barrier, Mutex};
+use vm_allocator::{AddressAllocator, SystemAllocator};
+use vm_device::{BusDevice, Resource};
+use vm_memory::{Address, GuestAddress};
+
+const PVPANIC_VENDOR_ID: u16 = 0x1b36;
+const PVPANIC_DEVICE_ID: u16 = 0x0011;
+
+pub const PVPANIC_DEVICE_MMIO_SIZE: u64 = 0x2;
+
 const PVPANIC_PANICKED: u8 = 1 << 0;
 const PVPANIC_CRASH_LOADED: u8 = 1 << 1;
 
+#[allow(dead_code)]
+#[derive(Copy, Clone)]
+pub enum PvPanicSubclass {
+    Other = 0x80,
+}
+
+impl PciSubclass for PvPanicSubclass {
+    fn get_register_value(&self) -> u8 {
+        *self as u8
+    }
+}
+
 /// A device for handling guest panic event
 pub struct PvPanicDevice {
-    _id: String,
-    _events: u8,
+    id: String,
+    events: u8,
+
+    // PCI configuration registers.
+    configuration: PciConfiguration,
+    bar_regions: Vec<PciBarConfiguration>,
 }
 
 impl PvPanicDevice {
-    pub fn new() -> PvPanicDevice {
+    pub fn new(id: String) -> PvPanicDevice {
+        let mut configuration = PciConfiguration::new(
+            PVPANIC_VENDOR_ID,
+            PVPANIC_DEVICE_ID,
+            0x1, // modern pci devices
+            PciClassCode::BaseSystemPeripheral,
+            &PvPanicSubclass::Other,
+            None,
+            PciHeaderType::Device,
+            0,
+            0,
+            None,
+            None,
+        );
+
+        let command: [u8; 2] = [0x03, 0x01];
+        configuration.write_config_register(1, 0, &command);
+
         let events = PVPANIC_PANICKED | PVPANIC_CRASH_LOADED;
 
         PvPanicDevice {
-            _id: String::from("_pvpanic"),
-            _events: events,
+            id,
+            events,
+            configuration,
+            bar_regions: vec![],
+        }
+    }
+
+    pub fn event_to_string(&self, event: u8) -> String {
+        if event == PVPANIC_PANICKED {
+            "panic".to_string()
+        } else if event == PVPANIC_CRASH_LOADED {
+            "crash_loaded".to_string()
+        } else {
+            "unknown_event".to_string()
         }
     }
 }
+
+impl BusDevice for PvPanicDevice {
+    fn read(&mut self, base: u64, offset: u64, data: &mut [u8]) {
+        self.read_bar(base, offset, data)
+    }
+
+    fn write(&mut self, _base: u64, _offset: u64, data: &[u8]) -> Option<Arc<Barrier>> {
+        let event = self.event_to_string(data[0]);
+        info!("pvpanic got guest event {}", event);
+        event!("guest", "panic", "event", &event);
+        None
+    }
+}
+
+impl PciDevice for PvPanicDevice {
+    fn write_config_register(
+        &mut self,
+        reg_idx: usize,
+        offset: u64,
+        data: &[u8],
+    ) -> Option<Arc<Barrier>> {
+        self.configuration
+            .write_config_register(reg_idx, offset, data);
+        None
+    }
+
+    fn read_config_register(&mut self, reg_idx: usize) -> u32 {
+        self.configuration.read_reg(reg_idx)
+    }
+
+    fn detect_bar_reprogramming(
+        &mut self,
+        reg_idx: usize,
+        data: &[u8],
+    ) -> Option<BarReprogrammingParams> {
+        self.configuration.detect_bar_reprogramming(reg_idx, data)
+    }
+
+    fn allocate_bars(
+        &mut self,
+        allocator: &Arc<Mutex<SystemAllocator>>,
+        _mmio_allocator: &mut AddressAllocator,
+        _resources: Option<Vec<Resource>>,
+    ) -> std::result::Result<Vec<PciBarConfiguration>, PciDeviceError> {
+        let mut bars = Vec::new();
+        let region_type = PciBarRegionType::Memory32BitRegion;
+        let bar_id = 0;
+        let region_size = PVPANIC_DEVICE_MMIO_SIZE;
+        let bar_addr = allocator
+            .lock()
+            .unwrap()
+            .allocate_mmio_hole_addresses(None, region_size, None)
+            .ok_or(PciDeviceError::IoAllocationFailed(region_size))?;
+
+        let bar = PciBarConfiguration::default()
+            .set_index(bar_id as usize)
+            .set_address(bar_addr.raw_value())
+            .set_size(region_size)
+            .set_region_type(region_type)
+            .set_prefetchable(PciBarPrefetchable::NotPrefetchable);
+
+        debug!("pvpanic bar address 0x{:x}", bar_addr.0);
+        self.configuration
+            .add_pci_bar(&bar)
+            .map_err(|e| PciDeviceError::IoRegistrationFailed(bar_addr.raw_value(), e))?;
+        bars.push(bar);
+        self.bar_regions = bars.clone();
+
+        Ok(bars)
+    }
+
+    fn free_bars(
+        &mut self,
+        allocator: &mut SystemAllocator,
+        _mmio_allocator: &mut AddressAllocator,
+    ) -> std::result::Result<(), PciDeviceError> {
+        for bar in self.bar_regions.drain(..) {
+            allocator.free_mmio_hole_addresses(GuestAddress(bar.addr()), bar.size());
+        }
+
+        Ok(())
+    }
+
+    fn move_bar(&mut self, old_base: u64, new_base: u64) -> result::Result<(), std::io::Error> {
+        for bar in self.bar_regions.iter_mut() {
+            if bar.addr() == old_base {
+                *bar = bar.set_address(new_base);
+            }
+        }
+
+        Ok(())
+    }
+
+    fn read_bar(&mut self, _base: u64, _offset: u64, data: &mut [u8]) {
+        data[0] = self.events;
+    }
+
+    fn as_any(&mut self) -> &mut dyn Any {
+        self
+    }
+
+    fn id(&self) -> Option<String> {
+        Some(self.id.clone())
+    }
+}