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// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2025 Meta Platforms, Inc. and affiliates. */
#include <vmlinux.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
#include "bpf_misc.h"
#include "bpf_experimental.h"
char _license[] SEC("license") = "GPL";
/* Timer tests */
struct timer_elem {
struct bpf_timer t;
};
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__uint(max_entries, 1);
__type(key, int);
__type(value, struct timer_elem);
} timer_map SEC(".maps");
static int timer_cb(void *map, int *key, struct bpf_timer *timer)
{
u32 data;
/* Timer callbacks are never sleepable, even from non-sleepable programs */
bpf_copy_from_user(&data, sizeof(data), NULL);
return 0;
}
SEC("fentry/bpf_fentry_test1")
__failure __msg("helper call might sleep in a non-sleepable prog")
int timer_non_sleepable_prog(void *ctx)
{
struct timer_elem *val;
int key = 0;
val = bpf_map_lookup_elem(&timer_map, &key);
if (!val)
return 0;
bpf_timer_init(&val->t, &timer_map, 0);
bpf_timer_set_callback(&val->t, timer_cb);
return 0;
}
SEC("lsm.s/file_open")
__failure __msg("helper call might sleep in a non-sleepable prog")
int timer_sleepable_prog(void *ctx)
{
struct timer_elem *val;
int key = 0;
val = bpf_map_lookup_elem(&timer_map, &key);
if (!val)
return 0;
bpf_timer_init(&val->t, &timer_map, 0);
bpf_timer_set_callback(&val->t, timer_cb);
return 0;
}
/* Workqueue tests */
struct wq_elem {
struct bpf_wq w;
};
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__uint(max_entries, 1);
__type(key, int);
__type(value, struct wq_elem);
} wq_map SEC(".maps");
static int wq_cb(void *map, int *key, void *value)
{
u32 data;
/* Workqueue callbacks are always sleepable, even from non-sleepable programs */
bpf_copy_from_user(&data, sizeof(data), NULL);
return 0;
}
SEC("fentry/bpf_fentry_test1")
__success
int wq_non_sleepable_prog(void *ctx)
{
struct wq_elem *val;
int key = 0;
val = bpf_map_lookup_elem(&wq_map, &key);
if (!val)
return 0;
if (bpf_wq_init(&val->w, &wq_map, 0) != 0)
return 0;
if (bpf_wq_set_callback_impl(&val->w, wq_cb, 0, NULL) != 0)
return 0;
return 0;
}
SEC("lsm.s/file_open")
__success
int wq_sleepable_prog(void *ctx)
{
struct wq_elem *val;
int key = 0;
val = bpf_map_lookup_elem(&wq_map, &key);
if (!val)
return 0;
if (bpf_wq_init(&val->w, &wq_map, 0) != 0)
return 0;
if (bpf_wq_set_callback_impl(&val->w, wq_cb, 0, NULL) != 0)
return 0;
return 0;
}
/* Task work tests */
struct task_work_elem {
struct bpf_task_work tw;
};
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__uint(max_entries, 1);
__type(key, int);
__type(value, struct task_work_elem);
} task_work_map SEC(".maps");
static int task_work_cb(struct bpf_map *map, void *key, void *value)
{
u32 data;
/* Task work callbacks are always sleepable, even from non-sleepable programs */
bpf_copy_from_user(&data, sizeof(data), NULL);
return 0;
}
SEC("fentry/bpf_fentry_test1")
__success
int task_work_non_sleepable_prog(void *ctx)
{
struct task_work_elem *val;
struct task_struct *task;
int key = 0;
val = bpf_map_lookup_elem(&task_work_map, &key);
if (!val)
return 0;
task = bpf_get_current_task_btf();
if (!task)
return 0;
bpf_task_work_schedule_resume_impl(task, &val->tw, &task_work_map, task_work_cb, NULL);
return 0;
}
SEC("lsm.s/file_open")
__success
int task_work_sleepable_prog(void *ctx)
{
struct task_work_elem *val;
struct task_struct *task;
int key = 0;
val = bpf_map_lookup_elem(&task_work_map, &key);
if (!val)
return 0;
task = bpf_get_current_task_btf();
if (!task)
return 0;
bpf_task_work_schedule_resume_impl(task, &val->tw, &task_work_map, task_work_cb, NULL);
return 0;
}
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