blob: 50fc5561110a470dd95a17430b515e0752c5a310 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2020 Facebook */
#include <linux/error-injection.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/percpu-defs.h>
#include <linux/sysfs.h>
#include <linux/tracepoint.h>
#include "bpf_testmod.h"
#define CREATE_TRACE_POINTS
#include "bpf_testmod-events.h"
DEFINE_PER_CPU(int, bpf_testmod_ksym_percpu) = 123;
noinline int bpf_testmod_loop_test(int n)
{
int i, sum = 0;
/* the primary goal of this test is to test LBR. Create a lot of
* branches in the function, so we can catch it easily.
*/
for (i = 0; i < n; i++)
sum += i;
return sum;
}
noinline ssize_t
bpf_testmod_test_read(struct file *file, struct kobject *kobj,
struct bin_attribute *bin_attr,
char *buf, loff_t off, size_t len)
{
struct bpf_testmod_test_read_ctx ctx = {
.buf = buf,
.off = off,
.len = len,
};
/* This is always true. Use the check to make sure the compiler
* doesn't remove bpf_testmod_loop_test.
*/
if (bpf_testmod_loop_test(101) > 100)
trace_bpf_testmod_test_read(current, &ctx);
return -EIO; /* always fail */
}
EXPORT_SYMBOL(bpf_testmod_test_read);
ALLOW_ERROR_INJECTION(bpf_testmod_test_read, ERRNO);
noinline ssize_t
bpf_testmod_test_write(struct file *file, struct kobject *kobj,
struct bin_attribute *bin_attr,
char *buf, loff_t off, size_t len)
{
struct bpf_testmod_test_write_ctx ctx = {
.buf = buf,
.off = off,
.len = len,
};
trace_bpf_testmod_test_write_bare(current, &ctx);
return -EIO; /* always fail */
}
EXPORT_SYMBOL(bpf_testmod_test_write);
ALLOW_ERROR_INJECTION(bpf_testmod_test_write, ERRNO);
static struct bin_attribute bin_attr_bpf_testmod_file __ro_after_init = {
.attr = { .name = "bpf_testmod", .mode = 0666, },
.read = bpf_testmod_test_read,
.write = bpf_testmod_test_write,
};
static int bpf_testmod_init(void)
{
return sysfs_create_bin_file(kernel_kobj, &bin_attr_bpf_testmod_file);
}
static void bpf_testmod_exit(void)
{
return sysfs_remove_bin_file(kernel_kobj, &bin_attr_bpf_testmod_file);
}
module_init(bpf_testmod_init);
module_exit(bpf_testmod_exit);
MODULE_AUTHOR("Andrii Nakryiko");
MODULE_DESCRIPTION("BPF selftests module");
MODULE_LICENSE("Dual BSD/GPL");