// SPDX-License-Identifier: GPL-2.0
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <sys/ioctl.h>
#include <linux/compiler.h>
#include <linux/hw_breakpoint.h>
#include <linux/kernel.h>
#include "tests.h"
#include "debug.h"
#include "event.h"
#include "cloexec.h"
#include "../perf-sys.h"
#define WP_TEST_ASSERT_VAL(fd, text, val) \
do { \
long long count; \
wp_read(fd, &count, sizeof(long long)); \
TEST_ASSERT_VAL(text, count == val); \
} while (0)
#ifdef __i386__
/* Only breakpoint length less-than 8 has hardware support on i386. */
volatile u32 data1;
#else
volatile u64 data1;
#endif
volatile u8 data2[3];
#ifndef __s390x__
static int wp_read(int fd, long long *count, int size)
{
int ret = read(fd, count, size);
if (ret != size) {
pr_debug("failed to read: %d\n", ret);
return -1;
}
return 0;
}
static void get__perf_event_attr(struct perf_event_attr *attr, int wp_type,
void *wp_addr, unsigned long wp_len)
{
memset(attr, 0, sizeof(struct perf_event_attr));
attr->type = PERF_TYPE_BREAKPOINT;
attr->size = sizeof(struct perf_event_attr);
attr->config = 0;
attr->bp_type = wp_type;
attr->bp_addr = (unsigned long)wp_addr;
attr->bp_len = wp_len;
attr->sample_period = 1;
attr->sample_type = PERF_SAMPLE_IP;
attr->exclude_kernel = 1;
attr->exclude_hv = 1;
}
static int __event(int wp_type, void *wp_addr, unsigned long wp_len)
{
int fd;
struct perf_event_attr attr;
get__perf_event_attr(&attr, wp_type, wp_addr, wp_len);
fd = sys_perf_event_open(&attr, 0, -1, -1,
perf_event_open_cloexec_flag());
if (fd < 0) {
fd = -errno;
pr_debug("failed opening event %x\n", attr.bp_type);
}
return fd;
}
#endif
static int test__wp_ro(struct test_suite *test __maybe_unused,
int subtest __maybe_unused)
{
#if defined(__s390x__) || defined(__x86_64__) || defined(__i386__)
return TEST_SKIP;
#else
int fd;
unsigned long tmp, tmp1 = rand();
fd = __event(HW_BREAKPOINT_R, (void *)&data1, sizeof(data1));
if (fd < 0)
return fd == -ENODEV ? TEST_SKIP : -1;
tmp = data1;
WP_TEST_ASSERT_VAL(fd, "RO watchpoint", 1);
data1 = tmp1 + tmp;
WP_TEST_ASSERT_VAL(fd, "RO watchpoint", 1);
close(fd);
return 0;
#endif
}
static int test__wp_wo(struct test_suite *test __maybe_unused,
int subtest __maybe_unused)
{
#if defined(__s390x__)
return TEST_SKIP;
#else
int fd;
unsigned long tmp, tmp1 = rand();
fd = __event(HW_BREAKPOINT_W, (void *)&data1, sizeof(data1));
if (fd < 0)
return fd == -ENODEV ? TEST_SKIP : -1;
tmp = data1;
WP_TEST_ASSERT_VAL(fd, "WO watchpoint", 0);
data1 = tmp1 + tmp;
WP_TEST_ASSERT_VAL(fd, "WO watchpoint", 1);
close(fd);
return 0;
#endif
}
static int test__wp_rw(struct test_suite *test __maybe_unused,
int subtest __maybe_unused)
{
#if defined(__s390x__)
return TEST_SKIP;
#else
int fd;
unsigned long tmp, tmp1 = rand();
fd = __event(HW_BREAKPOINT_R | HW_BREAKPOINT_W, (void *)&data1,
sizeof(data1));
if (fd < 0)
return fd == -ENODEV ? TEST_SKIP : -1;
tmp = data1;
WP_TEST_ASSERT_VAL(fd, "RW watchpoint", 1);
data1 = tmp1 + tmp;
WP_TEST_ASSERT_VAL(fd, "RW watchpoint", 2);
close(fd);
return 0;
#endif
}
static int test__wp_modify(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
{
#if defined(__s390x__)
return TEST_SKIP;
#else
int fd, ret;
unsigned long tmp = rand();
struct perf_event_attr new_attr;
fd = __event(HW_BREAKPOINT_W, (void *)&data1, sizeof(data1));
if (fd < 0)
return fd == -ENODEV ? TEST_SKIP : -1;
data1 = tmp;
WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 1);
/* Modify watchpoint with disabled = 1 */
get__perf_event_attr(&new_attr, HW_BREAKPOINT_W, (void *)&data2[0],
sizeof(u8) * 2);
new_attr.disabled = 1;
ret = ioctl(fd, PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &new_attr);
if (ret < 0) {
if (errno == ENOTTY) {
test->test_cases[subtest].skip_reason = "missing kernel support";
ret = TEST_SKIP;
}
pr_debug("ioctl(PERF_EVENT_IOC_MODIFY_ATTRIBUTES) failed\n");
close(fd);
return ret;
}
data2[1] = tmp; /* Not Counted */
WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 1);
/* Enable the event */
ioctl(fd, PERF_EVENT_IOC_ENABLE, 0);
if (ret < 0) {
pr_debug("Failed to enable event\n");
close(fd);
return ret;
}
data2[1] = tmp; /* Counted */
WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 2);
data2[2] = tmp; /* Not Counted */
WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 2);
close(fd);
return 0;
#endif
}
static struct test_case wp_tests[] = {
TEST_CASE_REASON("Read Only Watchpoint", wp_ro, "missing hardware support"),
TEST_CASE_REASON("Write Only Watchpoint", wp_wo, "missing hardware support"),
TEST_CASE_REASON("Read / Write Watchpoint", wp_rw, "missing hardware support"),
TEST_CASE_REASON("Modify Watchpoint", wp_modify, "missing hardware support"),
{ .name = NULL, }
};
struct test_suite suite__wp = {
.desc = "Watchpoint",
.test_cases = wp_tests,
};