1/* SPDX-License-Identifier: GPL-2.0 */
  2/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */
  3
  4#ifndef _CPUMASK_COMMON_H
  5#define _CPUMASK_COMMON_H
  6
  7#include "errno.h"
  8#include <stdbool.h>
  9
 10int err;
 11
 12#define private(name) SEC(".bss." #name) __hidden __attribute__((aligned(8)))
 13private(MASK) static struct bpf_cpumask __kptr * global_mask;
 14
 15struct __cpumask_map_value {
 16	struct bpf_cpumask __kptr * cpumask;
 17};
 18
 19struct array_map {
 20	__uint(type, BPF_MAP_TYPE_ARRAY);
 21	__type(key, int);
 22	__type(value, struct __cpumask_map_value);
 23	__uint(max_entries, 1);
 24} __cpumask_map SEC(".maps");
 25
 26struct bpf_cpumask *bpf_cpumask_create(void) __ksym;
 27void bpf_cpumask_release(struct bpf_cpumask *cpumask) __ksym;
 28struct bpf_cpumask *bpf_cpumask_acquire(struct bpf_cpumask *cpumask) __ksym;
 29u32 bpf_cpumask_first(const struct cpumask *cpumask) __ksym;
 30u32 bpf_cpumask_first_zero(const struct cpumask *cpumask) __ksym;
 31u32 bpf_cpumask_first_and(const struct cpumask *src1,
 32			  const struct cpumask *src2) __ksym;
 33void bpf_cpumask_set_cpu(u32 cpu, struct bpf_cpumask *cpumask) __ksym;
 34void bpf_cpumask_clear_cpu(u32 cpu, struct bpf_cpumask *cpumask) __ksym;
 35bool bpf_cpumask_test_cpu(u32 cpu, const struct cpumask *cpumask) __ksym;
 36bool bpf_cpumask_test_and_set_cpu(u32 cpu, struct bpf_cpumask *cpumask) __ksym;
 37bool bpf_cpumask_test_and_clear_cpu(u32 cpu, struct bpf_cpumask *cpumask) __ksym;
 38void bpf_cpumask_setall(struct bpf_cpumask *cpumask) __ksym;
 39void bpf_cpumask_clear(struct bpf_cpumask *cpumask) __ksym;
 40bool bpf_cpumask_and(struct bpf_cpumask *cpumask,
 41		     const struct cpumask *src1,
 42		     const struct cpumask *src2) __ksym;
 43void bpf_cpumask_or(struct bpf_cpumask *cpumask,
 44		    const struct cpumask *src1,
 45		    const struct cpumask *src2) __ksym;
 46void bpf_cpumask_xor(struct bpf_cpumask *cpumask,
 47		     const struct cpumask *src1,
 48		     const struct cpumask *src2) __ksym;
 49bool bpf_cpumask_equal(const struct cpumask *src1, const struct cpumask *src2) __ksym;
 50bool bpf_cpumask_intersects(const struct cpumask *src1, const struct cpumask *src2) __ksym;
 51bool bpf_cpumask_subset(const struct cpumask *src1, const struct cpumask *src2) __ksym;
 52bool bpf_cpumask_empty(const struct cpumask *cpumask) __ksym;
 53bool bpf_cpumask_full(const struct cpumask *cpumask) __ksym;
 54void bpf_cpumask_copy(struct bpf_cpumask *dst, const struct cpumask *src) __ksym;
 55u32 bpf_cpumask_any_distribute(const struct cpumask *src) __ksym;
 56u32 bpf_cpumask_any_and_distribute(const struct cpumask *src1, const struct cpumask *src2) __ksym;
 57u32 bpf_cpumask_weight(const struct cpumask *cpumask) __ksym;
 58
 59void bpf_rcu_read_lock(void) __ksym;
 60void bpf_rcu_read_unlock(void) __ksym;
 61
 62static inline const struct cpumask *cast(struct bpf_cpumask *cpumask)
 63{
 64	return (const struct cpumask *)cpumask;
 65}
 66
 67static inline struct bpf_cpumask *create_cpumask(void)
 68{
 69	struct bpf_cpumask *cpumask;
 70
 71	cpumask = bpf_cpumask_create();
 72	if (!cpumask) {
 73		err = 1;
 74		return NULL;
 75	}
 76
 77	if (!bpf_cpumask_empty(cast(cpumask))) {
 78		err = 2;
 79		bpf_cpumask_release(cpumask);
 80		return NULL;
 81	}
 82
 83	return cpumask;
 84}
 85
 86static inline struct __cpumask_map_value *cpumask_map_value_lookup(void)
 87{
 88	u32 key = 0;
 89
 90	return bpf_map_lookup_elem(&__cpumask_map, &key);
 91}
 92
 93static inline int cpumask_map_insert(struct bpf_cpumask *mask)
 94{
 95	struct __cpumask_map_value local, *v;
 96	long status;
 97	struct bpf_cpumask *old;
 98	u32 key = 0;
 99
100	local.cpumask = NULL;
101	status = bpf_map_update_elem(&__cpumask_map, &key, &local, 0);
102	if (status) {
103		bpf_cpumask_release(mask);
104		return status;
105	}
106
107	v = bpf_map_lookup_elem(&__cpumask_map, &key);
108	if (!v) {
109		bpf_cpumask_release(mask);
110		return -ENOENT;
111	}
112
113	old = bpf_kptr_xchg(&v->cpumask, mask);
114	if (old) {
115		bpf_cpumask_release(old);
116		return -EEXIST;
117	}
118
119	return 0;
120}
121
122#endif /* _CPUMASK_COMMON_H */