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These methods were stabilized in Rust 1.80.0, which is the current minimum supported Rust version for the kernel. This simplifies from_bytes_prefix(), from_bytes_mut_prefix(), and from_bytes_copy_prefix() by removing the explicit bounds checks and panic-avoidance comments that are no longer needed. Signed-off-by: Albab Hasan --- rust/kernel/transmute.rs | 33 ++++++--------------------------- 1 file changed, 6 insertions(+), 27 deletions(-) diff --git a/rust/kernel/transmute.rs b/rust/kernel/transmute.rs index 5711580c9f9b..643b19406a24 100644 --- a/rust/kernel/transmute.rs +++ b/rust/kernel/transmute.rs @@ -67,16 +67,9 @@ fn from_bytes_prefix(bytes: &[u8]) -> Option<(&Self, &[u8])> where Self: Sized, { - if bytes.len() < size_of::() { - None - } else { - // PANIC: We checked that `bytes.len() >= size_of::`, thus `split_at` cannot - // panic. - // TODO: replace with `split_at_checked` once the MSRV is >= 1.80. - let (prefix, remainder) = bytes.split_at(size_of::()); + let (prefix, remainder) = bytes.split_at_checked(size_of::())?; - Self::from_bytes(prefix).map(|s| (s, remainder)) - } + Self::from_bytes(prefix).map(|s| (s, remainder)) } /// Converts a mutable slice of bytes to a reference to `Self`. @@ -110,16 +103,9 @@ fn from_bytes_mut_prefix(bytes: &mut [u8]) -> Option<(&mut Self, &mut [u8])> where Self: AsBytes + Sized, { - if bytes.len() < size_of::() { - None - } else { - // PANIC: We checked that `bytes.len() >= size_of::`, thus `split_at_mut` cannot - // panic. - // TODO: replace with `split_at_mut_checked` once the MSRV is >= 1.80. - let (prefix, remainder) = bytes.split_at_mut(size_of::()); + let (prefix, remainder) = bytes.split_at_mut_checked(size_of::())?; - Self::from_bytes_mut(prefix).map(|s| (s, remainder)) - } + Self::from_bytes_mut(prefix).map(|s| (s, remainder)) } /// Creates an owned instance of `Self` by copying `bytes`. @@ -149,16 +135,9 @@ fn from_bytes_copy_prefix(bytes: &[u8]) -> Option<(Self, &[u8])> where Self: Sized, { - if bytes.len() < size_of::() { - None - } else { - // PANIC: We checked that `bytes.len() >= size_of::`, thus `split_at` cannot - // panic. - // TODO: replace with `split_at_checked` once the MSRV is >= 1.80. - let (prefix, remainder) = bytes.split_at(size_of::()); + let (prefix, remainder) = bytes.split_at_checked(size_of::())?; - Self::from_bytes_copy(prefix).map(|s| (s, remainder)) - } + Self::from_bytes_copy(prefix).map(|s| (s, remainder)) } } -- 2.43.0