[PATCH 1/2] rust: Add cpumask helpers

From: Yury Norov
Date: Fri Feb 21 2025 - 15:59:36 EST


From: Viresh Kumar <viresh.kumar@xxxxxxxxxx>

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.

Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Signed-off-by: Yury Norov [NVIDIA] <yury.norov@xxxxxxxxx>
---
Yury: a bit more wording in commit description.

Question: zalloc_cpumask_war() is a convenient wrapper around
alloc_cpumask_var_node(). Maybe rust can use the latter directly as it's
a true outlined function? There's more flexibility, if you need it, but
also a higher risk that the API will change: ~40 users vs 180 for zalloc
thing. Up to you guys. I can send v2 if needed.

rust/bindings/bindings_helper.h | 1 +
rust/helpers/cpumask.c | 40 +++++++++++++++++++++++++++++++++
rust/helpers/helpers.c | 1 +
3 files changed, 42 insertions(+)
create mode 100644 rust/helpers/cpumask.c

diff --git a/rust/bindings/bindings_helper.h b/rust/bindings/bindings_helper.h
index f46cf3bb7069..2396ca1cf8fb 100644
--- a/rust/bindings/bindings_helper.h
+++ b/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>
diff --git a/rust/helpers/cpumask.c b/rust/helpers/cpumask.c
new file mode 100644
index 000000000000..df4b1a2853a9
--- /dev/null
+++ b/rust/helpers/cpumask.c
@@ -0,0 +1,40 @@
+// 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_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
diff --git a/rust/helpers/helpers.c b/rust/helpers/helpers.c
index 0640b7e115be..de2341cfd917 100644
--- a/rust/helpers/helpers.c
+++ b/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"
--
2.43.0