From 5fce802722cd4435a748d89043615324db4efe5e Mon Sep 17 00:00:00 2001
From: "Bjoern A. Zeeb" <bz@FreeBSD.org>
Date: Mon, 24 May 2021 18:01:59 +0000
Subject: [PATCH] LinuxKPI: add cpu.h for cpumask_*()

Add linux/cpu.h for cpumask_*() functions found in wireless drivers
and make sure cpu_online_mask is always initialised.

Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
Reviewed by:	hselasky
Differential Revision: https://reviews.freebsd.org/D30421
---
 .../linuxkpi/common/include/linux/cpu.h       | 76 +++++++++++++++++++
 sys/compat/linuxkpi/common/src/linux_compat.c |  4 +
 2 files changed, 80 insertions(+)
 create mode 100644 sys/compat/linuxkpi/common/include/linux/cpu.h

diff --git a/sys/compat/linuxkpi/common/include/linux/cpu.h b/sys/compat/linuxkpi/common/include/linux/cpu.h
new file mode 100644
index 000000000000..5be8f3d5a0d5
--- /dev/null
+++ b/sys/compat/linuxkpi/common/include/linux/cpu.h
@@ -0,0 +1,76 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2020-2021 The FreeBSD Foundation
+ *
+ * This software was developed by Björn Zeeb under sponsorship from
+ * the FreeBSD Foundation.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef	__LKPI_LINUX_CPU_H
+#define	__LKPI_LINUX_CPU_H
+
+#include <sys/types.h>
+#include <sys/systm.h>
+#include <sys/cpuset.h>
+#include <sys/smp.h>
+#include <linux/compiler.h>
+#include <linux/slab.h>
+
+typedef	cpuset_t	cpumask_t;
+
+extern cpumask_t cpu_online_mask;
+
+static __inline int
+cpumask_next(int cpuid, cpumask_t mask)
+{
+
+	/*
+	 * -1 can be an input to cpuid according to logic in drivers
+	 * but is never a valid cpuid in a set!
+	 */
+	KASSERT((cpuid >= -1 && cpuid <= MAXCPU), ("%s: invalid cpuid %d\n",
+	    __func__, cpuid));
+	KASSERT(!CPU_EMPTY(&mask), ("%s: empty CPU mask", __func__));
+
+	do {
+		cpuid++;
+#ifdef SMP
+		if (cpuid > mp_maxid)
+#endif
+			cpuid = 0;
+	} while (!CPU_ISSET(cpuid, &mask));
+	return (cpuid);
+}
+
+static __inline void
+cpumask_set_cpu(int cpu, cpumask_t *mask)
+{
+
+	CPU_SET(cpu, mask);
+}
+
+#endif	/* __LKPI_LINUX_CPU_H */
diff --git a/sys/compat/linuxkpi/common/src/linux_compat.c b/sys/compat/linuxkpi/common/src/linux_compat.c
index a8f090ed0bd5..ef570dda542c 100644
--- a/sys/compat/linuxkpi/common/src/linux_compat.c
+++ b/sys/compat/linuxkpi/common/src/linux_compat.c
@@ -67,6 +67,7 @@ __FBSDID("$FreeBSD$");
 #endif
 
 #include <linux/kobject.h>
+#include <linux/cpu.h>
 #include <linux/device.h>
 #include <linux/slab.h>
 #include <linux/module.h>
@@ -119,6 +120,7 @@ static void linux_destroy_dev(struct linux_cdev *);
 static void linux_cdev_deref(struct linux_cdev *ldev);
 static struct vm_area_struct *linux_cdev_handle_find(void *handle);
 
+cpumask_t cpu_online_mask;
 struct kobject linux_class_root;
 struct device linux_root_device;
 struct class linux_class_misc;
@@ -2627,6 +2629,8 @@ linux_compat_init(void *arg)
 		LIST_INIT(&vmmaphead[i]);
 	init_waitqueue_head(&linux_bit_waitq);
 	init_waitqueue_head(&linux_var_waitq);
+
+	CPU_COPY(&all_cpus, &cpu_online_mask);
 }
 SYSINIT(linux_compat, SI_SUB_DRIVERS, SI_ORDER_SECOND, linux_compat_init, NULL);