Switch to Rust param ops for all ints

Rust-for-Linux · Feb 15, 2021 · 1f96a0f · 1f96a0f
1 parent 0164184
commit 1f96a0f
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Showing 2 changed files with 78 additions and 8 deletions.
diff --git a/rust/kernel/module_param.rs b/rust/kernel/module_param.rs
@@ -43,12 +43,76 @@ pub trait ModuleParam : core::fmt::Display + core::marker::Sized {
     }
 }
 
+/// Trait for parsing integers. Strings begining with `0x`, `0o`, or `0b` are
+/// parsed as hex, octal, or binary respectively. Strings beginning with `0`
+/// otherwise are parsed as octal. Anything else is parsed as decimal. A
+/// leading `+` or `-` is also permitted. Any string parsed by `kstrtol` or
+/// `kstrtoul` will be successfully parsed.
+trait ParseInt : Sized {
+    fn from_str_radix(src: &str, radix: u32) -> Result<Self, core::num::ParseIntError>;
+    fn checked_neg(self) -> Option<Self>;
+
+    fn from_str_unsigned(src: &str) -> Result<Self, core::num::ParseIntError> {
+        let (radix, digits) = if let Some(n) = src.strip_prefix("0x") {
+            (16, n)
+        } else if let Some(n) = src.strip_prefix("0X") {
+            (16, n)
+        } else if let Some(n) = src.strip_prefix("0o") {
+            (8, n)
+        } else if let Some(n) = src.strip_prefix("0O") {
+            (8, n)
+        } else if let Some(n) = src.strip_prefix("0b") {
+            (2, n)
+        } else if let Some(n) = src.strip_prefix("0B") {
+            (2, n)
+        } else if src.starts_with("0") {
+            (8, src)
+        } else {
+            (10, src)
+        };
+        Self::from_str_radix(digits, radix)
+    }
+
+    fn from_str(src: &str) -> Option<Self> {
+        match src.bytes().next() {
+            None => None,
+            Some(b'-') => Self::from_str_unsigned(&src[1..]).ok()?.checked_neg(),
+            Some(b'+') => Some(Self::from_str_unsigned(&src[1..]).ok()?),
+            Some(_) => Some(Self::from_str_unsigned(src).ok()?),
+        }
+    }
+}
+
+macro_rules! impl_parse_int {
+    ($ty:ident) => {
+        impl ParseInt for $ty {
+            fn from_str_radix(src: &str, radix: u32) -> Result<Self, core::num::ParseIntError> {
+                $ty::from_str_radix(src, radix)
+            }
+            fn checked_neg(self) -> Option<Self> {
+                self.checked_neg()
+            }
+        }
+    }
+}
+
+impl_parse_int!(i8);
+impl_parse_int!(u8);
+impl_parse_int!(i16);
+impl_parse_int!(u16);
+impl_parse_int!(i32);
+impl_parse_int!(u32);
+impl_parse_int!(i64);
+impl_parse_int!(u64);
+impl_parse_int!(isize);
+impl_parse_int!(usize);
+
 macro_rules! make_param_ops {
     ($ops:ident, $ty:ident) => {
         impl ModuleParam for $ty {
             fn try_from_param_arg(arg: &[u8]) -> Option<Self> {
                 let utf8 = core::str::from_utf8(arg).ok()?;
-                utf8.parse::<$ty>().ok()
+                <$ty as crate::module_param::ParseInt>::from_str(utf8)
             }
         }
 
@@ -62,6 +126,12 @@ macro_rules! make_param_ops {
 }
 
 make_param_ops!(PARAM_OPS_I8, i8);
+make_param_ops!(PARAM_OPS_U8, u8);
+make_param_ops!(PARAM_OPS_I16, i16);
+make_param_ops!(PARAM_OPS_U16, u16);
+make_param_ops!(PARAM_OPS_I32, i32);
+make_param_ops!(PARAM_OPS_U32, u32);
 make_param_ops!(PARAM_OPS_I64, i64);
-make_param_ops!(PARAM_OPS_USIZE, usize);
+make_param_ops!(PARAM_OPS_U64, u64);
 make_param_ops!(PARAM_OPS_ISIZE, isize);
+make_param_ops!(PARAM_OPS_USIZE, usize);
diff --git a/rust/module.rs b/rust/module.rs
@@ -284,13 +284,13 @@ pub fn module(ts: TokenStream) -> TokenStream {
         let (param_kernel_type, ops) = match param_type.as_ref() {
             "bool" => ("bool", "kernel::bindings::param_ops_bool"),
             "i8" => ("i8", "kernel::module_param::PARAM_OPS_I8"),
-            "u8" => ("u8", "kernel::bindings::param_ops_char"),
-            "i16" => ("i16", "kernel::bindings::param_ops_short"),
-            "u16" => ("u16", "kernel::bindings::param_ops_ushort"),
-            "i32" => ("i32", "kernel::bindings::param_ops_int"),
-            "u32" => ("u32", "kernel::bindings::param_ops_uint"),
+            "u8" => ("u8", "kernel::module_param::PARAM_OPS_U8"),
+            "i16" => ("i16", "kernel::module_param::PARAM_OPS_I16"),
+            "u16" => ("u16", "kernel::module_param::PARAM_OPS_U16"),
+            "i32" => ("i32", "kernel::module_param::PARAM_OPS_I32"),
+            "u32" => ("u32", "kernel::module_param::PARAM_OPS_U32"),
             "i64" => ("i64", "kernel::module_param::PARAM_OPS_I64"),
-            "u64" => ("u64", "kernel::bindings::param_ops_ullong"),
+            "u64" => ("u64", "kernel::module_param::PARAM_OPS_U64"),
             "isize" => ("isize", "kernel::module_param::PARAM_OPS_ISIZE"),
             "usize" => ("usize", "kernel::module_param::PARAM_OPS_USIZE"),
             "str" => ("charp", "kernel::bindings::param_ops_charp"),