1 // SPDX-License-Identifier: GPL-2.0
2 #include <stdlib.h>
3 #include <string.h>
4 #include <unistd.h>
5 #include <errno.h>
6 #include <sys/ioctl.h>
7 #include <linux/compiler.h>
8 #include <linux/hw_breakpoint.h>
9 #include <linux/kernel.h>
10 #include "tests.h"
11 #include "debug.h"
12 #include "event.h"
13 #include "cloexec.h"
14 #include "../perf-sys.h"
15
16 #define WP_TEST_ASSERT_VAL(fd, text, val) \
17 do { \
18 long long count; \
19 wp_read(fd, &count, sizeof(long long)); \
20 TEST_ASSERT_VAL(text, count == val); \
21 } while (0)
22
23 volatile u64 data1;
24 volatile u8 data2[3];
25
26 #ifndef __s390x__
27 static int wp_read(int fd, long long *count, int size)
28 {
29 int ret = read(fd, count, size);
30
31 if (ret != size) {
32 pr_debug("failed to read: %d\n", ret);
33 return -1;
34 }
35 return 0;
36 }
37
38 static void get__perf_event_attr(struct perf_event_attr *attr, int wp_type,
39 void *wp_addr, unsigned long wp_len)
40 {
41 memset(attr, 0, sizeof(struct perf_event_attr));
42 attr->type = PERF_TYPE_BREAKPOINT;
43 attr->size = sizeof(struct perf_event_attr);
44 attr->config = 0;
45 attr->bp_type = wp_type;
46 attr->bp_addr = (unsigned long)wp_addr;
47 attr->bp_len = wp_len;
48 attr->sample_period = 1;
49 attr->sample_type = PERF_SAMPLE_IP;
50 attr->exclude_kernel = 1;
51 attr->exclude_hv = 1;
52 }
53
54 static int __event(int wp_type, void *wp_addr, unsigned long wp_len)
55 {
56 int fd;
57 struct perf_event_attr attr;
58
59 get__perf_event_attr(&attr, wp_type, wp_addr, wp_len);
60 fd = sys_perf_event_open(&attr, 0, -1, -1,
61 perf_event_open_cloexec_flag());
62 if (fd < 0) {
63 fd = -errno;
64 pr_debug("failed opening event %x\n", attr.bp_type);
65 }
66
67 return fd;
68 }
69 #endif
70
71 static int test__wp_ro(struct test_suite *test __maybe_unused,
72 int subtest __maybe_unused)
73 {
74 #if defined(__s390x__) || defined(__x86_64__) || defined(__i386__)
75 return TEST_SKIP;
76 #else
77 int fd;
78 unsigned long tmp, tmp1 = rand();
79
80 fd = __event(HW_BREAKPOINT_R, (void *)&data1, sizeof(data1));
81 if (fd < 0)
82 return fd == -ENODEV ? TEST_SKIP : -1;
83
84 tmp = data1;
85 WP_TEST_ASSERT_VAL(fd, "RO watchpoint", 1);
86
87 data1 = tmp1 + tmp;
88 WP_TEST_ASSERT_VAL(fd, "RO watchpoint", 1);
89
90 close(fd);
91 return 0;
92 #endif
93 }
94
95 static int test__wp_wo(struct test_suite *test __maybe_unused,
96 int subtest __maybe_unused)
97 {
98 #if defined(__s390x__)
99 return TEST_SKIP;
100 #else
101 int fd;
102 unsigned long tmp, tmp1 = rand();
103
104 fd = __event(HW_BREAKPOINT_W, (void *)&data1, sizeof(data1));
105 if (fd < 0)
106 return fd == -ENODEV ? TEST_SKIP : -1;
107
108 tmp = data1;
109 WP_TEST_ASSERT_VAL(fd, "WO watchpoint", 0);
110
111 data1 = tmp1 + tmp;
112 WP_TEST_ASSERT_VAL(fd, "WO watchpoint", 1);
113
114 close(fd);
115 return 0;
116 #endif
117 }
118
119 static int test__wp_rw(struct test_suite *test __maybe_unused,
120 int subtest __maybe_unused)
121 {
122 #if defined(__s390x__)
123 return TEST_SKIP;
124 #else
125 int fd;
126 unsigned long tmp, tmp1 = rand();
127
128 fd = __event(HW_BREAKPOINT_R | HW_BREAKPOINT_W, (void *)&data1,
129 sizeof(data1));
130 if (fd < 0)
131 return fd == -ENODEV ? TEST_SKIP : -1;
132
133 tmp = data1;
134 WP_TEST_ASSERT_VAL(fd, "RW watchpoint", 1);
135
136 data1 = tmp1 + tmp;
137 WP_TEST_ASSERT_VAL(fd, "RW watchpoint", 2);
138
139 close(fd);
140 return 0;
141 #endif
142 }
143
144 static int test__wp_modify(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
145 {
146 #if defined(__s390x__)
147 return TEST_SKIP;
148 #else
149 int fd, ret;
150 unsigned long tmp = rand();
151 struct perf_event_attr new_attr;
152
153 fd = __event(HW_BREAKPOINT_W, (void *)&data1, sizeof(data1));
154 if (fd < 0)
155 return fd == -ENODEV ? TEST_SKIP : -1;
156
157 data1 = tmp;
158 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 1);
159
160 /* Modify watchpoint with disabled = 1 */
161 get__perf_event_attr(&new_attr, HW_BREAKPOINT_W, (void *)&data2[0],
162 sizeof(u8) * 2);
163 new_attr.disabled = 1;
164 ret = ioctl(fd, PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &new_attr);
165 if (ret < 0) {
166 if (errno == ENOTTY) {
167 test->test_cases[subtest].skip_reason = "missing kernel support";
168 ret = TEST_SKIP;
169 }
170
171 pr_debug("ioctl(PERF_EVENT_IOC_MODIFY_ATTRIBUTES) failed\n");
172 close(fd);
173 return ret;
174 }
175
176 data2[1] = tmp; /* Not Counted */
177 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 1);
178
179 /* Enable the event */
180 ioctl(fd, PERF_EVENT_IOC_ENABLE, 0);
181 if (ret < 0) {
182 pr_debug("Failed to enable event\n");
183 close(fd);
184 return ret;
185 }
186
187 data2[1] = tmp; /* Counted */
188 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 2);
189
190 data2[2] = tmp; /* Not Counted */
191 WP_TEST_ASSERT_VAL(fd, "Modify watchpoint", 2);
192
193 close(fd);
194 return 0;
195 #endif
196 }
197
198 static struct test_case wp_tests[] = {
199 TEST_CASE_REASON("Read Only Watchpoint", wp_ro, "missing hardware support"),
200 TEST_CASE_REASON("Write Only Watchpoint", wp_wo, "missing hardware support"),
201 TEST_CASE_REASON("Read / Write Watchpoint", wp_rw, "missing hardware support"),
202 TEST_CASE_REASON("Modify Watchpoint", wp_modify, "missing hardware support"),
203 { .name = NULL, }
204 };
205
206 struct test_suite suite__wp = {
207 .desc = "Watchpoint",
208 .test_cases = wp_tests,
209 };
210
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