rust: module_param: support bool parameters

Add support for parsing boolean module parameters in the Rust
module! macro.

Currently, only integer types are supported by the `module_param!`
macros. This patch implements the `ModuleParam` trait for `bool`
by delegating the string parsing to the existing C implementation
via `kstrtobool_bytes()`. It also wires up `PARAM_OPS_BOOL` so that
the Rust parameter system correctly links to the C `param_ops_bool`
structure.

For demonstration and verification, a boolean parameter is added
to `samples/rust/rust_minimal.rs`.

Support for boolean parameters will initially be used by the Rust
null block driver [1].

Link: https://lore.kernel.org/all/20260609-rnull-v6-19-rc5-send-v2-4-82c7404542e2@kernel.org/ [1]
Assisted-by: Codex:GPT-5
Signed-off-by: Wenzhao Liao <wenzhaoliao@ruc.edu.cn>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://lore.kernel.org/linux-modules/20260411130254.3510128-1-wenzhaoliao@ruc.edu.cn/
[ppavlu: add motivation to the commit message and rebase the patch]
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/samples/rust/rust_minimal.rs b/samples/rust/rust_minimal.rs
index 60d03df6cd80..8c910d314dfa 100644
--- a/samples/rust/rust_minimal.rs
+++ b/samples/rust/rust_minimal.rs
@@ -15,6 +15,10 @@ module! {
             default: 1,
             description: "This parameter has a default of 1",
         },
+        test_bool_parameter: bool {
+            default: false,
+            description: "This boolean parameter defaults to false",
+        },
     },
 }
 
@@ -30,6 +34,10 @@ impl kernel::Module for RustMinimal {
             "test_parameter: {}\n",
             module_parameters::test_parameter.value()
         );
+        pr_info!(
+            "test_bool_parameter: {}\n",
+            module_parameters::test_bool_parameter.value()
+        );
 
         let mut numbers = KVec::new();
         numbers.push(72, GFP_KERNEL)?;