rust: helpers: add SRCU helpers

Add helper wrappers for SRCU functions that are exposed to Rust
through generated bindings.

Signed-off-by: Onur Özkan <work@onurozkan.dev>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Boqun Feng <boqun@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

rust/helpers/helpers.c

@@ -91,6 +91,7 @@
 #include "slab.c"
 #include "spinlock.c"
 #include "string.c"
+#include "srcu.c"
 #include "sync.c"
 #include "task.c"
 #include "time.c"

rust/helpers/srcu.c

@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/srcu.h>
+
+__rust_helper int rust_helper_init_srcu_struct_with_key(struct srcu_struct *ssp,
+							const char *name,
+							struct lock_class_key *key)
+{
+	return __init_srcu_struct(ssp, name, key);
+}
+
+__rust_helper int rust_helper_srcu_read_lock(struct srcu_struct *ssp)
+{
+	return srcu_read_lock(ssp);
+}
+
+__rust_helper void rust_helper_srcu_read_unlock(struct srcu_struct *ssp, int idx)
+{
+	srcu_read_unlock(ssp, idx);
+}
+
+__rust_helper void rust_helper_srcu_barrier(struct srcu_struct *ssp)
+{
+	srcu_barrier(ssp);
+}
+
+__rust_helper void rust_helper_synchronize_srcu_expedited(struct srcu_struct *ssp)
+{
+	synchronize_srcu_expedited(ssp);
+}