rust: Add cpumask helpers

In order to prepare for adding Rust abstractions for cpumask, add
the required helpers for inline cpumask functions that cannot be
called by rust code directly.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Yury Norov [NVIDIA] <yury.norov@gmail.com>

rust/bindings/bindings_helper.h

@@ -10,6 +10,7 @@
 #include <linux/blk-mq.h>
 #include <linux/blk_types.h>
 #include <linux/blkdev.h>
+#include <linux/cpumask.h>
 #include <linux/cred.h>
 #include <linux/device/faux.h>
 #include <linux/errname.h>

rust/helpers/cpumask.c

@@ -0,0 +1,45 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/cpumask.h>
+
+void rust_helper_cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
+{
+	cpumask_set_cpu(cpu, dstp);
+}
+
+void rust_helper_cpumask_clear_cpu(int cpu, struct cpumask *dstp)
+{
+	cpumask_clear_cpu(cpu, dstp);
+}
+
+void rust_helper_cpumask_setall(struct cpumask *dstp)
+{
+	cpumask_setall(dstp);
+}
+
+unsigned int rust_helper_cpumask_weight(struct cpumask *srcp)
+{
+	return cpumask_weight(srcp);
+}
+
+void rust_helper_cpumask_copy(struct cpumask *dstp, const struct cpumask *srcp)
+{
+	cpumask_copy(dstp, srcp);
+}
+
+bool rust_helper_alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
+{
+	return alloc_cpumask_var(mask, flags);
+}
+
+bool rust_helper_zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
+{
+	return zalloc_cpumask_var(mask, flags);
+}
+
+#ifndef CONFIG_CPUMASK_OFFSTACK
+void rust_helper_free_cpumask_var(cpumask_var_t mask)
+{
+	free_cpumask_var(mask);
+}
+#endif

rust/helpers/helpers.c

@@ -11,6 +11,7 @@
 #include "bug.c"
 #include "build_assert.c"
 #include "build_bug.c"
+#include "cpumask.c"
 #include "cred.c"
 #include "device.c"
 #include "err.c"