fix: add try_mem() to PciBar, fix virtio-core caller

Added try_mem() returning Option<(usize, usize)> for non-panicking
memory BAR access. Fixed virtio-core/probe.rs to use .ok_or() instead
of .map_err() to match the Option return type.

Cargo.lock

@@ -1325,6 +1325,7 @@ dependencies = [
  "daemon",
  "driver-network",
  "libredox",
+ "log",
  "pcid",
  "redox_event",
  "redox_syscall 0.9.0+rb0.3.1",
@@ -2411,6 +2412,15 @@ dependencies = [
  "numtoa",
 ]
 
+[[package]]
+name = "thermald"
+version = "0.1.0"
+dependencies = [
+ "anyhow",
+ "common",
+ "log",
+]
+
 [[package]]
 name = "thiserror"
 version = "1.0.69"

drivers/pcid/src/driver_interface/bar.rs

@@ -52,4 +52,17 @@ impl PciBar {
             PciBar::None => panic!("expected BAR to exist"),
         }
     }
+
+    pub fn try_mem(&self) -> Option<(usize, usize)> {
+        match *self {
+            PciBar::Memory32 { addr, size } => Some((addr as usize, size as usize)),
+            PciBar::Memory64 { addr, size } => Some((
+                addr.try_into()
+                    .expect("conversion from 64bit BAR to usize failed"),
+                size.try_into()
+                    .expect("conversion from 64bit BAR size to usize failed"),
+            )),
+            _ => None,
+        }
+    }
 }

drivers/virtio-core/src/probe.rs

@@ -57,7 +57,7 @@ pub fn probe_device(pcid_handle: &mut PciFunctionHandle) -> Result<Device, Error
 
         let (addr, _) = pci_config.func.bars[capability.bar as usize]
             .try_mem()
-            .map_err(|_| Error::Probe("BAR is not memory-mapped"))?;
+            .ok_or(Error::Probe("BAR is not memory-mapped"))?;
 
         let address = unsafe {
             let addr = addr + capability.offset as usize;