`build_assert` relies on the compiler to optimize out its error path. Functions using it with its arguments must thus always be inlined, otherwise the error path of `build_assert` might not be optimized out, triggering a build error.
Cc: stable@vger.kernel.org Fixes: ce30d94e6855 ("rust: add `io::{Io, IoRaw}` base types") Reviewed-by: Daniel Almeida daniel.almeida@collabora.com Signed-off-by: Alexandre Courbot acourbot@nvidia.com --- rust/kernel/io.rs | 9 ++++++--- rust/kernel/io/resource.rs | 2 ++ 2 files changed, 8 insertions(+), 3 deletions(-)
diff --git a/rust/kernel/io.rs b/rust/kernel/io.rs index 98e8b84e68d1..b64b11f75a35 100644 --- a/rust/kernel/io.rs +++ b/rust/kernel/io.rs @@ -142,7 +142,8 @@ macro_rules! define_read { /// Bound checks are performed on compile time, hence if the offset is not known at compile /// time, the build will fail. $(#[$attr])* - #[inline] + // Always inline to optimize out error path of `io_addr_assert`. + #[inline(always)] pub fn $name(&self, offset: usize) -> $type_name { let addr = self.io_addr_assert::<$type_name>(offset);
@@ -171,7 +172,8 @@ macro_rules! define_write { /// Bound checks are performed on compile time, hence if the offset is not known at compile /// time, the build will fail. $(#[$attr])* - #[inline] + // Always inline to optimize out error path of `io_addr_assert`. + #[inline(always)] pub fn $name(&self, value: $type_name, offset: usize) { let addr = self.io_addr_assert::<$type_name>(offset);
@@ -239,7 +241,8 @@ fn io_addr<U>(&self, offset: usize) -> Result<usize> { self.addr().checked_add(offset).ok_or(EINVAL) }
- #[inline] + // Always inline to optimize out error path of `build_assert`. + #[inline(always)] fn io_addr_assert<U>(&self, offset: usize) -> usize { build_assert!(Self::offset_valid::<U>(offset, SIZE));
diff --git a/rust/kernel/io/resource.rs b/rust/kernel/io/resource.rs index 56cfde97ce87..b7ac9faf141d 100644 --- a/rust/kernel/io/resource.rs +++ b/rust/kernel/io/resource.rs @@ -226,6 +226,8 @@ impl Flags { /// Resource represents a memory region that must be ioremaped using `ioremap_np`. pub const IORESOURCE_MEM_NONPOSTED: Flags = Flags::new(bindings::IORESOURCE_MEM_NONPOSTED);
+ // Always inline to optimize out error path of `build_assert`. + #[inline(always)] const fn new(value: u32) -> Self { crate::build_assert!(value as u64 <= c_ulong::MAX as u64); Flags(value as c_ulong)