[PATCH] rust: Add support for feeding entropy to randomness pool

[Matthew Maurer <mmaurer@google.com>]

Adds just enough support to allow device drivers to feed entropy to the
central pool.

Signed-off-by: Matthew Maurer <mmaurer@google.com>
---
 rust/kernel/lib.rs  |  1 +
 rust/kernel/rand.rs | 14 ++++++++++++++
 2 files changed, 15 insertions(+)

diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index f812cf12004286962985a068665443dc22c389a2..f93886ef4eec9c4356799f4b55916bc12c10c621 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -128,6 +128,7 @@
 pub mod print;
 pub mod processor;
 pub mod ptr;
+pub mod rand;
 #[cfg(CONFIG_RUST_PWM_ABSTRACTIONS)]
 pub mod pwm;
 pub mod rbtree;
diff --git a/rust/kernel/rand.rs b/rust/kernel/rand.rs
new file mode 100644
index 0000000000000000000000000000000000000000..b3fb30f40a8950ac7b47d48129eb89024a1cbd26
--- /dev/null
+++ b/rust/kernel/rand.rs
@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Randomness.
+//!
+//! C header: [`include/linux/random.h`](../../../../include/linux/random.h)
+
+use crate::bindings;
+use crate::ffi::c_void;
+
+/// Adds the given buffer to the entropy pool.
+pub fn add_device_randomness(buf: &[u8]) {
+    // SAFETY: We just need the pointer to be valid for the length, which a slice provides.
+    unsafe { bindings::add_device_randomness(buf.as_ptr().cast::<c_void>(), buf.len()) };
+}

---
base-commit: 008d3547aae5bc86fac3eda317489169c3fda112
change-id: 20251029-add-entropy-f57e12ebe110

Best regards,
-- 
Matthew Maurer <mmaurer@google.com>