1 | // SPDX-License-Identifier: GPL-2.0 |
2 | #include <malloc.h> |
3 | #include <stdlib.h> |
4 | #include <string.h> |
5 | #include <sys/mman.h> |
6 | #include <time.h> |
7 | |
8 | #include "utils.h" |
9 | |
10 | #define SIZE 256 |
11 | #define ITERATIONS 10000 |
12 | |
13 | #define LARGE_SIZE (5 * 1024) |
14 | #define LARGE_ITERATIONS 1000 |
15 | #define LARGE_MAX_OFFSET 32 |
16 | #define LARGE_SIZE_START 4096 |
17 | |
18 | /* This is big enough to fit LARGE_SIZE and works on 4K & 64K kernels */ |
19 | #define MAP_SIZE (64 * 1024) |
20 | |
21 | #define MAX_OFFSET_DIFF_S1_S2 48 |
22 | |
23 | int vmx_count; |
24 | int enter_vmx_ops(void) |
25 | { |
26 | vmx_count++; |
27 | return 1; |
28 | } |
29 | |
30 | void exit_vmx_ops(void) |
31 | { |
32 | vmx_count--; |
33 | } |
34 | int test_memcmp(const void *s1, const void *s2, size_t n); |
35 | |
36 | /* test all offsets and lengths */ |
37 | static void test_one(char *s1, char *s2, unsigned long max_offset, |
38 | unsigned long size_start, unsigned long max_size) |
39 | { |
40 | unsigned long offset, size; |
41 | |
42 | for (offset = 0; offset < max_offset; offset++) { |
43 | for (size = size_start; size < (max_size - offset); size++) { |
44 | int x, y; |
45 | unsigned long i; |
46 | |
47 | y = memcmp(s1+offset, s2+offset, size); |
48 | x = test_memcmp(s1+offset, s2+offset, size); |
49 | |
50 | if (((x ^ y) < 0) && /* Trick to compare sign */ |
51 | ((x | y) != 0)) { /* check for zero */ |
52 | printf("memcmp returned %d, should have returned %d (offset %ld size %ld)\n" , x, y, offset, size); |
53 | |
54 | for (i = offset; i < offset+size; i++) |
55 | printf("%02x " , s1[i]); |
56 | printf("\n" ); |
57 | |
58 | for (i = offset; i < offset+size; i++) |
59 | printf("%02x " , s2[i]); |
60 | printf("\n" ); |
61 | abort(); |
62 | } |
63 | |
64 | if (vmx_count != 0) { |
65 | printf("vmx enter/exit not paired.(offset:%ld size:%ld s1:%p s2:%p vc:%d\n" , |
66 | offset, size, s1, s2, vmx_count); |
67 | printf("\n" ); |
68 | abort(); |
69 | } |
70 | } |
71 | } |
72 | } |
73 | |
74 | static int testcase(bool islarge) |
75 | { |
76 | unsigned long i, comp_size, alloc_size; |
77 | char *p, *s1, *s2; |
78 | int iterations; |
79 | |
80 | comp_size = (islarge ? LARGE_SIZE : SIZE); |
81 | alloc_size = comp_size + MAX_OFFSET_DIFF_S1_S2; |
82 | iterations = islarge ? LARGE_ITERATIONS : ITERATIONS; |
83 | |
84 | p = mmap(NULL, 4 * MAP_SIZE, PROT_READ | PROT_WRITE, |
85 | MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); |
86 | FAIL_IF(p == MAP_FAILED); |
87 | |
88 | /* Put s1/s2 at the end of a page */ |
89 | s1 = p + MAP_SIZE - alloc_size; |
90 | s2 = p + 3 * MAP_SIZE - alloc_size; |
91 | |
92 | /* And unmap the subsequent page to force a fault if we overread */ |
93 | munmap(p + MAP_SIZE, MAP_SIZE); |
94 | munmap(p + 3 * MAP_SIZE, MAP_SIZE); |
95 | |
96 | srandom(time(0)); |
97 | |
98 | for (i = 0; i < iterations; i++) { |
99 | unsigned long j; |
100 | unsigned long change; |
101 | char *rand_s1 = s1; |
102 | char *rand_s2 = s2; |
103 | |
104 | for (j = 0; j < alloc_size; j++) |
105 | s1[j] = random(); |
106 | |
107 | rand_s1 += random() % MAX_OFFSET_DIFF_S1_S2; |
108 | rand_s2 += random() % MAX_OFFSET_DIFF_S1_S2; |
109 | memcpy(rand_s2, rand_s1, comp_size); |
110 | |
111 | /* change one byte */ |
112 | change = random() % comp_size; |
113 | rand_s2[change] = random() & 0xff; |
114 | |
115 | if (islarge) |
116 | test_one(s1: rand_s1, s2: rand_s2, LARGE_MAX_OFFSET, |
117 | LARGE_SIZE_START, max_size: comp_size); |
118 | else |
119 | test_one(s1: rand_s1, s2: rand_s2, SIZE, size_start: 0, max_size: comp_size); |
120 | } |
121 | |
122 | srandom(time(0)); |
123 | |
124 | for (i = 0; i < iterations; i++) { |
125 | unsigned long j; |
126 | unsigned long change; |
127 | char *rand_s1 = s1; |
128 | char *rand_s2 = s2; |
129 | |
130 | for (j = 0; j < alloc_size; j++) |
131 | s1[j] = random(); |
132 | |
133 | rand_s1 += random() % MAX_OFFSET_DIFF_S1_S2; |
134 | rand_s2 += random() % MAX_OFFSET_DIFF_S1_S2; |
135 | memcpy(rand_s2, rand_s1, comp_size); |
136 | |
137 | /* change multiple bytes, 1/8 of total */ |
138 | for (j = 0; j < comp_size / 8; j++) { |
139 | change = random() % comp_size; |
140 | s2[change] = random() & 0xff; |
141 | } |
142 | |
143 | if (islarge) |
144 | test_one(s1: rand_s1, s2: rand_s2, LARGE_MAX_OFFSET, |
145 | LARGE_SIZE_START, max_size: comp_size); |
146 | else |
147 | test_one(s1: rand_s1, s2: rand_s2, SIZE, size_start: 0, max_size: comp_size); |
148 | } |
149 | |
150 | return 0; |
151 | } |
152 | |
153 | static int testcases(void) |
154 | { |
155 | #ifdef __powerpc64__ |
156 | // vcmpequd used in memcmp_64.S is v2.07 |
157 | SKIP_IF(!have_hwcap2(PPC_FEATURE2_ARCH_2_07)); |
158 | #endif |
159 | |
160 | testcase(0); |
161 | testcase(1); |
162 | return 0; |
163 | } |
164 | |
165 | int main(void) |
166 | { |
167 | test_harness_set_timeout(300); |
168 | return test_harness(testcases, "memcmp" ); |
169 | } |
170 | |