1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */
3 #include <errno.h>
4 #include <sys/syscall.h>
5 #include <unistd.h>
6 #include "test_global_map_resize.skel.h"
7 #include "test_progs.h"
8
run_prog_bss_array_sum(void)9 static void run_prog_bss_array_sum(void)
10 {
11 (void)syscall(__NR_getpid);
12 }
13
run_prog_data_array_sum(void)14 static void run_prog_data_array_sum(void)
15 {
16 (void)syscall(__NR_getuid);
17 }
18
global_map_resize_bss_subtest(void)19 static void global_map_resize_bss_subtest(void)
20 {
21 int err;
22 struct test_global_map_resize *skel;
23 struct bpf_map *map;
24 const __u32 desired_sz = sizeof(skel->bss->sum) + sysconf(_SC_PAGE_SIZE) * 2;
25 size_t array_len, actual_sz, new_sz;
26
27 skel = test_global_map_resize__open();
28 if (!ASSERT_OK_PTR(skel, "test_global_map_resize__open"))
29 goto teardown;
30
31 /* set some initial value before resizing.
32 * it is expected this non-zero value will be preserved
33 * while resizing.
34 */
35 skel->bss->array[0] = 1;
36
37 /* resize map value and verify the new size */
38 map = skel->maps.bss;
39 err = bpf_map__set_value_size(map, desired_sz);
40 if (!ASSERT_OK(err, "bpf_map__set_value_size"))
41 goto teardown;
42 if (!ASSERT_EQ(bpf_map__value_size(map), desired_sz, "resize"))
43 goto teardown;
44
45 new_sz = sizeof(skel->data_percpu_arr->percpu_arr[0]) * libbpf_num_possible_cpus();
46 err = bpf_map__set_value_size(skel->maps.data_percpu_arr, new_sz);
47 ASSERT_OK(err, "percpu_arr_resize");
48
49 /* set the expected number of elements based on the resized array */
50 array_len = (desired_sz - sizeof(skel->bss->sum)) / sizeof(skel->bss->array[0]);
51 if (!ASSERT_GT(array_len, 1, "array_len"))
52 goto teardown;
53
54 skel->bss = bpf_map__initial_value(skel->maps.bss, &actual_sz);
55 if (!ASSERT_OK_PTR(skel->bss, "bpf_map__initial_value (ptr)"))
56 goto teardown;
57 if (!ASSERT_EQ(actual_sz, desired_sz, "bpf_map__initial_value (size)"))
58 goto teardown;
59
60 /* fill the newly resized array with ones,
61 * skipping the first element which was previously set
62 */
63 for (int i = 1; i < array_len; i++)
64 skel->bss->array[i] = 1;
65
66 /* set global const values before loading */
67 skel->rodata->pid = getpid();
68 skel->rodata->bss_array_len = array_len;
69 skel->rodata->data_array_len = 1;
70
71 err = test_global_map_resize__load(skel);
72 if (!ASSERT_OK(err, "test_global_map_resize__load"))
73 goto teardown;
74 err = test_global_map_resize__attach(skel);
75 if (!ASSERT_OK(err, "test_global_map_resize__attach"))
76 goto teardown;
77
78 /* run the bpf program which will sum the contents of the array.
79 * since the array was filled with ones,verify the sum equals array_len
80 */
81 run_prog_bss_array_sum();
82 if (!ASSERT_EQ(skel->bss->sum, array_len, "sum"))
83 goto teardown;
84
85 teardown:
86 test_global_map_resize__destroy(skel);
87 }
88
global_map_resize_data_subtest(void)89 static void global_map_resize_data_subtest(void)
90 {
91 struct test_global_map_resize *skel;
92 struct bpf_map *map;
93 const __u32 desired_sz = sysconf(_SC_PAGE_SIZE) * 2;
94 size_t array_len, actual_sz, new_sz;
95 int err;
96
97 skel = test_global_map_resize__open();
98 if (!ASSERT_OK_PTR(skel, "test_global_map_resize__open"))
99 goto teardown;
100
101 /* set some initial value before resizing.
102 * it is expected this non-zero value will be preserved
103 * while resizing.
104 */
105 skel->data_custom->my_array[0] = 1;
106
107 /* resize map value and verify the new size */
108 map = skel->maps.data_custom;
109 err = bpf_map__set_value_size(map, desired_sz);
110 if (!ASSERT_OK(err, "bpf_map__set_value_size"))
111 goto teardown;
112 if (!ASSERT_EQ(bpf_map__value_size(map), desired_sz, "resize"))
113 goto teardown;
114
115 new_sz = sizeof(skel->data_percpu_arr->percpu_arr[0]) * libbpf_num_possible_cpus();
116 err = bpf_map__set_value_size(skel->maps.data_percpu_arr, new_sz);
117 ASSERT_OK(err, "percpu_arr_resize");
118
119 /* set the expected number of elements based on the resized array */
120 array_len = (desired_sz - sizeof(skel->bss->sum)) / sizeof(skel->data_custom->my_array[0]);
121 if (!ASSERT_GT(array_len, 1, "array_len"))
122 goto teardown;
123
124 skel->data_custom = bpf_map__initial_value(skel->maps.data_custom, &actual_sz);
125 if (!ASSERT_OK_PTR(skel->data_custom, "bpf_map__initial_value (ptr)"))
126 goto teardown;
127 if (!ASSERT_EQ(actual_sz, desired_sz, "bpf_map__initial_value (size)"))
128 goto teardown;
129
130 /* fill the newly resized array with ones,
131 * skipping the first element which was previously set
132 */
133 for (int i = 1; i < array_len; i++)
134 skel->data_custom->my_array[i] = 1;
135
136 /* set global const values before loading */
137 skel->rodata->pid = getpid();
138 skel->rodata->bss_array_len = 1;
139 skel->rodata->data_array_len = array_len;
140
141 err = test_global_map_resize__load(skel);
142 if (!ASSERT_OK(err, "test_global_map_resize__load"))
143 goto teardown;
144 err = test_global_map_resize__attach(skel);
145 if (!ASSERT_OK(err, "test_global_map_resize__attach"))
146 goto teardown;
147
148 /* run the bpf program which will sum the contents of the array.
149 * since the array was filled with ones,verify the sum equals array_len
150 */
151 run_prog_data_array_sum();
152 if (!ASSERT_EQ(skel->bss->sum, array_len, "sum"))
153 goto teardown;
154
155 teardown:
156 test_global_map_resize__destroy(skel);
157 }
158
global_map_resize_invalid_subtest(void)159 static void global_map_resize_invalid_subtest(void)
160 {
161 int err;
162 struct test_global_map_resize *skel;
163 struct bpf_map *map;
164 __u32 element_sz, desired_sz;
165
166 skel = test_global_map_resize__open();
167 if (!ASSERT_OK_PTR(skel, "test_global_map_resize__open"))
168 return;
169
170 /* attempt to resize a global datasec map to size
171 * which does NOT align with array
172 */
173 map = skel->maps.data_custom;
174 if (!ASSERT_NEQ(bpf_map__btf_value_type_id(map), 0, ".data.custom initial btf"))
175 goto teardown;
176 /* set desired size a fraction of element size beyond an aligned size */
177 element_sz = sizeof(skel->data_custom->my_array[0]);
178 desired_sz = element_sz + element_sz / 2;
179 /* confirm desired size does NOT align with array */
180 if (!ASSERT_NEQ(desired_sz % element_sz, 0, "my_array alignment"))
181 goto teardown;
182 err = bpf_map__set_value_size(map, desired_sz);
183 /* confirm resize is OK but BTF info is cleared */
184 if (!ASSERT_OK(err, ".data.custom bpf_map__set_value_size") ||
185 !ASSERT_EQ(bpf_map__btf_key_type_id(map), 0, ".data.custom clear btf key") ||
186 !ASSERT_EQ(bpf_map__btf_value_type_id(map), 0, ".data.custom clear btf val"))
187 goto teardown;
188
189 /* attempt to resize a global datasec map whose only var is NOT an array */
190 map = skel->maps.data_non_array;
191 if (!ASSERT_NEQ(bpf_map__btf_value_type_id(map), 0, ".data.non_array initial btf"))
192 goto teardown;
193 /* set desired size to arbitrary value */
194 desired_sz = 1024;
195 err = bpf_map__set_value_size(map, desired_sz);
196 /* confirm resize is OK but BTF info is cleared */
197 if (!ASSERT_OK(err, ".data.non_array bpf_map__set_value_size") ||
198 !ASSERT_EQ(bpf_map__btf_key_type_id(map), 0, ".data.non_array clear btf key") ||
199 !ASSERT_EQ(bpf_map__btf_value_type_id(map), 0, ".data.non_array clear btf val"))
200 goto teardown;
201
202 /* attempt to resize a global datasec map
203 * whose last var is NOT an array
204 */
205 map = skel->maps.data_array_not_last;
206 if (!ASSERT_NEQ(bpf_map__btf_value_type_id(map), 0, ".data.array_not_last initial btf"))
207 goto teardown;
208 /* set desired size to a multiple of element size */
209 element_sz = sizeof(skel->data_array_not_last->my_array_first[0]);
210 desired_sz = element_sz * 8;
211 /* confirm desired size aligns with array */
212 if (!ASSERT_EQ(desired_sz % element_sz, 0, "my_array_first alignment"))
213 goto teardown;
214 err = bpf_map__set_value_size(map, desired_sz);
215 /* confirm resize is OK but BTF info is cleared */
216 if (!ASSERT_OK(err, ".data.array_not_last bpf_map__set_value_size") ||
217 !ASSERT_EQ(bpf_map__btf_key_type_id(map), 0, ".data.array_not_last clear btf key") ||
218 !ASSERT_EQ(bpf_map__btf_value_type_id(map), 0, ".data.array_not_last clear btf val"))
219 goto teardown;
220
221 teardown:
222 test_global_map_resize__destroy(skel);
223 }
224
test_global_map_resize(void)225 void test_global_map_resize(void)
226 {
227 if (test__start_subtest("global_map_resize_bss"))
228 global_map_resize_bss_subtest();
229
230 if (test__start_subtest("global_map_resize_data"))
231 global_map_resize_data_subtest();
232
233 if (test__start_subtest("global_map_resize_invalid"))
234 global_map_resize_invalid_subtest();
235 }
236