Merge pull request #1133 from mkroening/non-exhaustive-platforms

refactor: make platform matches non-exhaustive

src/arch/x86_64/kernel/mod.rs

@@ -1,5 +1,6 @@
 #[cfg(feature = "common-os")]
 use core::arch::asm;
+use core::num::NonZeroU64;
 #[cfg(feature = "newlib")]
 use core::slice;
 use core::sync::atomic::{AtomicU32, AtomicU64, Ordering};
@@ -71,14 +72,13 @@ pub fn get_limit() -> usize {
 	boot_info().hardware_info.phys_addr_range.end as usize
 }
 
-pub fn get_mbinfo() -> VirtAddr {
+pub fn get_mbinfo() -> Option<NonZeroU64> {
 	match boot_info().platform_info {
 		PlatformInfo::Multiboot {
 			multiboot_info_addr,
 			..
-		} => VirtAddr(multiboot_info_addr.get()),
-		PlatformInfo::LinuxBootParams { .. } => VirtAddr(0),
-		PlatformInfo::Uhyve { .. } => VirtAddr(0),
+		} => Some(multiboot_info_addr),
+		_ => None,
 	}
 }
 
@@ -94,13 +94,12 @@ pub fn get_possible_cpus() -> u32 {
 	use core::cmp;
 
 	match boot_info().platform_info {
-		PlatformInfo::LinuxBootParams { .. } => apic::local_apic_id_count(),
-		PlatformInfo::Multiboot { .. } => apic::local_apic_id_count(),
 		// FIXME: Remove get_processor_count after a transition period for uhyve 0.1.3 adoption
 		PlatformInfo::Uhyve { num_cpus, .. } => cmp::max(
 			u32::try_from(num_cpus.get()).unwrap(),
 			get_processor_count(),
 		),
+		_ => apic::local_apic_id_count(),
 	}
 }
 
@@ -115,18 +114,17 @@ pub fn get_processor_count() -> u32 {
 }
 
 pub fn is_uhyve_with_pci() -> bool {
-	match boot_info().platform_info {
-		PlatformInfo::Multiboot { .. } => false,
-		PlatformInfo::LinuxBootParams { .. } => false,
-		PlatformInfo::Uhyve { has_pci, .. } => has_pci,
-	}
+	matches!(
+		boot_info().platform_info,
+		PlatformInfo::Uhyve { has_pci: true, .. }
+	)
 }
 
 pub fn args() -> Option<&'static str> {
 	match boot_info().platform_info {
 		PlatformInfo::Multiboot { command_line, .. } => command_line,
 		PlatformInfo::LinuxBootParams { command_line, .. } => command_line,
-		PlatformInfo::Uhyve { .. } => None,
+		_ => None,
 	}
 }
 

src/arch/x86_64/kernel/processor.rs

@@ -371,12 +371,11 @@ impl CpuFrequency {
 	fn detect_from_hypervisor(&mut self) -> Result<(), ()> {
 		fn detect_from_uhyve() -> Result<u16, ()> {
 			match boot_info().platform_info {
-				PlatformInfo::Multiboot { .. } => Err(()),
-				PlatformInfo::LinuxBootParams { .. } => Err(()),
 				PlatformInfo::Uhyve { cpu_freq, .. } => Ok(u16::try_from(
 					cpu_freq.map(NonZeroU32::get).unwrap_or_default() / 1000,
 				)
 				.unwrap()),
+				_ => Err(()),
 			}
 		}
 		// future implementations could add support for different hypervisors
@@ -1038,7 +1037,8 @@ fn qemu_exit(success: bool) {
 pub fn shutdown(error_code: i32) -> ! {
 	match boot_info().platform_info {
 		PlatformInfo::LinuxBootParams { .. } => triple_fault(),
-		PlatformInfo::Multiboot { .. } => {
+		PlatformInfo::Uhyve { .. } => unreachable!(),
+		_ => {
 			qemu_exit(error_code == 0);
 
 			#[cfg(feature = "acpi")]
@@ -1050,7 +1050,6 @@ pub fn shutdown(error_code: i32) -> ! {
 				halt();
 			}
 		}
-		PlatformInfo::Uhyve { .. } => unreachable!(),
 	}
 }
 

src/arch/x86_64/kernel/systemtime.rs

@@ -174,21 +174,14 @@ static BOOT_TIME: OnceCell<u64> = OnceCell::new();
 
 pub fn init() {
 	let boot_time = match boot_info().platform_info {
-		PlatformInfo::Multiboot { .. } => {
-			// Get the current time in microseconds since the epoch (1970-01-01) from the x86 RTC.
-			// Subtract the timer ticks to get the actual time when Hermit was booted.
-			let current_time = without_interrupts(|| Rtc::new().get_microseconds_since_epoch());
-			let boot_time = current_time - processor::get_timer_ticks();
-			OffsetDateTime::from_unix_timestamp_nanos(boot_time as i128 * 1000).unwrap()
-		}
-		PlatformInfo::LinuxBootParams { .. } => {
+		PlatformInfo::Uhyve { boot_time, .. } => boot_time,
+		_ => {
 			// Get the current time in microseconds since the epoch (1970-01-01) from the x86 RTC.
 			// Subtract the timer ticks to get the actual time when Hermit was booted.
 			let current_time = without_interrupts(|| Rtc::new().get_microseconds_since_epoch());
 			let boot_time = current_time - processor::get_timer_ticks();
 			OffsetDateTime::from_unix_timestamp_nanos(boot_time as i128 * 1000).unwrap()
 		}
-		PlatformInfo::Uhyve { boot_time, .. } => boot_time,
 	};
 	info!("Hermit booted on {boot_time}");
 

src/arch/x86_64/mm/physicalmem.rs

@@ -62,13 +62,10 @@ fn detect_from_fdt() -> Result<(), ()> {
 }
 
 fn detect_from_multiboot_info() -> Result<(), ()> {
-	let mb_info = get_mbinfo();
-	if mb_info.is_zero() {
-		return Err(());
-	}
+	let mb_info = get_mbinfo().ok_or(())?.get();
 
 	let mut mem = MultibootMemory;
-	let mb = unsafe { Multiboot::from_ptr(mb_info.as_u64(), &mut mem).unwrap() };
+	let mb = unsafe { Multiboot::from_ptr(mb_info, &mut mem).unwrap() };
 	let all_regions = mb
 		.memory_regions()
 		.expect("Could not find a memory map in the Multiboot information");