[PATCH WIP 3/5] rust: Add support for feeding entropy to randomness pool

[Matthew Maurer <mmaurer@google.com>]

(This will be separately sent to the list later.)

Signed-off-by: Matthew Maurer <mmaurer@google.com>
---
 rust/bindings/bindings_helper.h |  1 +
 rust/kernel/lib.rs              |  1 +
 rust/kernel/rand.rs             | 14 ++++++++++++++
 3 files changed, 16 insertions(+)

diff --git a/rust/bindings/bindings_helper.h b/rust/bindings/bindings_helper.h
index 140e2f4e60c0b745ac5d5c7456d60af28e21f55a..afe8be55a6db1d29706c19a91dc51c1ae3494ed4 100644
--- a/rust/bindings/bindings_helper.h
+++ b/rust/bindings/bindings_helper.h
@@ -67,6 +67,7 @@
 #include <linux/pm_opp.h>
 #include <linux/poll.h>
 #include <linux/property.h>
+#include <linux/random.h>
 #include <linux/refcount.h>
 #include <linux/regulator/consumer.h>
 #include <linux/sched.h>
diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index 0461f25cb5aee797d25153a2004d63b6b41f4ae3..39a9088a8d63f0ae54a0101eaeb03b17f82e12e8 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -112,6 +112,7 @@
 pub mod platform;
 pub mod prelude;
 pub mod print;
+pub mod rand;
 pub mod rbtree;
 pub mod regulator;
 pub mod revocable;
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()) };
+}

-- 
2.51.0.rc1.167.g924127e9c0-goog