1// SPDX-License-Identifier: GPL-2.0-only
2/* MSG_ZEROCOPY feature tests for vsock
3 *
4 * Copyright (C) 2023 SberDevices.
5 *
6 * Author: Arseniy Krasnov <avkrasnov@salutedevices.com>
7 */
8
9#include <stdio.h>
10#include <stdlib.h>
11#include <string.h>
12#include <sys/mman.h>
13#include <unistd.h>
14#include <poll.h>
15#include <linux/errqueue.h>
16#include <linux/kernel.h>
17#include <errno.h>
18
19#include "control.h"
20#include "vsock_test_zerocopy.h"
21#include "msg_zerocopy_common.h"
22
23#ifndef PAGE_SIZE
24#define PAGE_SIZE 4096
25#endif
26
27#define VSOCK_TEST_DATA_MAX_IOV 3
28
29struct vsock_test_data {
30 /* This test case if for SOCK_STREAM only. */
31 bool stream_only;
32 /* Data must be zerocopied. This field is checked against
33 * field 'ee_code' of the 'struct sock_extended_err', which
34 * contains bit to detect that zerocopy transmission was
35 * fallbacked to copy mode.
36 */
37 bool zerocopied;
38 /* Enable SO_ZEROCOPY option on the socket. Without enabled
39 * SO_ZEROCOPY, every MSG_ZEROCOPY transmission will behave
40 * like without MSG_ZEROCOPY flag.
41 */
42 bool so_zerocopy;
43 /* 'errno' after 'sendmsg()' call. */
44 int sendmsg_errno;
45 /* Number of valid elements in 'vecs'. */
46 int vecs_cnt;
47 struct iovec vecs[VSOCK_TEST_DATA_MAX_IOV];
48};
49
50static struct vsock_test_data test_data_array[] = {
51 /* Last element has non-page aligned size. */
52 {
53 .zerocopied = true,
54 .so_zerocopy = true,
55 .sendmsg_errno = 0,
56 .vecs_cnt = 3,
57 {
58 { NULL, PAGE_SIZE },
59 { NULL, PAGE_SIZE },
60 { NULL, 200 }
61 }
62 },
63 /* All elements have page aligned base and size. */
64 {
65 .zerocopied = true,
66 .so_zerocopy = true,
67 .sendmsg_errno = 0,
68 .vecs_cnt = 3,
69 {
70 { NULL, PAGE_SIZE },
71 { NULL, PAGE_SIZE * 2 },
72 { NULL, PAGE_SIZE * 3 }
73 }
74 },
75 /* All elements have page aligned base and size. But
76 * data length is bigger than 64Kb.
77 */
78 {
79 .zerocopied = true,
80 .so_zerocopy = true,
81 .sendmsg_errno = 0,
82 .vecs_cnt = 3,
83 {
84 { NULL, PAGE_SIZE * 16 },
85 { NULL, PAGE_SIZE * 16 },
86 { NULL, PAGE_SIZE * 16 }
87 }
88 },
89 /* Middle element has both non-page aligned base and size. */
90 {
91 .zerocopied = true,
92 .so_zerocopy = true,
93 .sendmsg_errno = 0,
94 .vecs_cnt = 3,
95 {
96 { NULL, PAGE_SIZE },
97 { (void *)1, 100 },
98 { NULL, PAGE_SIZE }
99 }
100 },
101 /* Middle element is unmapped. */
102 {
103 .zerocopied = false,
104 .so_zerocopy = true,
105 .sendmsg_errno = ENOMEM,
106 .vecs_cnt = 3,
107 {
108 { NULL, PAGE_SIZE },
109 { MAP_FAILED, PAGE_SIZE },
110 { NULL, PAGE_SIZE }
111 }
112 },
113 /* Valid data, but SO_ZEROCOPY is off. This
114 * will trigger fallback to copy.
115 */
116 {
117 .zerocopied = false,
118 .so_zerocopy = false,
119 .sendmsg_errno = 0,
120 .vecs_cnt = 1,
121 {
122 { NULL, PAGE_SIZE }
123 }
124 },
125 /* Valid data, but message is bigger than peer's
126 * buffer, so this will trigger fallback to copy.
127 * This test is for SOCK_STREAM only, because
128 * for SOCK_SEQPACKET, 'sendmsg()' returns EMSGSIZE.
129 */
130 {
131 .stream_only = true,
132 .zerocopied = false,
133 .so_zerocopy = true,
134 .sendmsg_errno = 0,
135 .vecs_cnt = 1,
136 {
137 { NULL, 100 * PAGE_SIZE }
138 }
139 },
140};
141
142#define POLL_TIMEOUT_MS 100
143
144static void test_client(const struct test_opts *opts,
145 const struct vsock_test_data *test_data,
146 bool sock_seqpacket)
147{
148 struct pollfd fds = { 0 };
149 struct msghdr msg = { 0 };
150 ssize_t sendmsg_res;
151 struct iovec *iovec;
152 int fd;
153
154 if (sock_seqpacket)
155 fd = vsock_seqpacket_connect(cid: opts->peer_cid, port: opts->peer_port);
156 else
157 fd = vsock_stream_connect(cid: opts->peer_cid, port: opts->peer_port);
158
159 if (fd < 0) {
160 perror("connect");
161 exit(EXIT_FAILURE);
162 }
163
164 if (test_data->so_zerocopy)
165 enable_so_zerocopy(fd);
166
167 iovec = alloc_test_iovec(test_iovec: test_data->vecs, iovnum: test_data->vecs_cnt);
168
169 msg.msg_iov = iovec;
170 msg.msg_iovlen = test_data->vecs_cnt;
171
172 errno = 0;
173
174 sendmsg_res = sendmsg(fd, &msg, MSG_ZEROCOPY);
175 if (errno != test_data->sendmsg_errno) {
176 fprintf(stderr, "expected 'errno' == %i, got %i\n",
177 test_data->sendmsg_errno, errno);
178 exit(EXIT_FAILURE);
179 }
180
181 if (!errno) {
182 if (sendmsg_res != iovec_bytes(iov: iovec, iovnum: test_data->vecs_cnt)) {
183 fprintf(stderr, "expected 'sendmsg()' == %li, got %li\n",
184 iovec_bytes(iov: iovec, iovnum: test_data->vecs_cnt),
185 sendmsg_res);
186 exit(EXIT_FAILURE);
187 }
188 }
189
190 fds.fd = fd;
191 fds.events = 0;
192
193 if (poll(&fds, 1, POLL_TIMEOUT_MS) < 0) {
194 perror("poll");
195 exit(EXIT_FAILURE);
196 }
197
198 if (fds.revents & POLLERR) {
199 vsock_recv_completion(fd, zerocopied: &test_data->zerocopied);
200 } else if (test_data->so_zerocopy && !test_data->sendmsg_errno) {
201 /* If we don't have data in the error queue, but
202 * SO_ZEROCOPY was enabled and 'sendmsg()' was
203 * successful - this is an error.
204 */
205 fprintf(stderr, "POLLERR expected\n");
206 exit(EXIT_FAILURE);
207 }
208
209 if (!test_data->sendmsg_errno)
210 control_writeulong(value: iovec_hash_djb2(iov: iovec, iovnum: test_data->vecs_cnt));
211 else
212 control_writeulong(value: 0);
213
214 control_writeln(str: "DONE");
215 free_test_iovec(test_iovec: test_data->vecs, iovec, iovnum: test_data->vecs_cnt);
216 close(fd);
217}
218
219void test_stream_msgzcopy_client(const struct test_opts *opts)
220{
221 int i;
222
223 for (i = 0; i < ARRAY_SIZE(test_data_array); i++)
224 test_client(opts, &test_data_array[i], false);
225}
226
227void test_seqpacket_msgzcopy_client(const struct test_opts *opts)
228{
229 int i;
230
231 for (i = 0; i < ARRAY_SIZE(test_data_array); i++) {
232 if (test_data_array[i].stream_only)
233 continue;
234
235 test_client(opts, &test_data_array[i], true);
236 }
237}
238
239static void test_server(const struct test_opts *opts,
240 const struct vsock_test_data *test_data,
241 bool sock_seqpacket)
242{
243 unsigned long remote_hash;
244 unsigned long local_hash;
245 ssize_t total_bytes_rec;
246 unsigned char *data;
247 size_t data_len;
248 int fd;
249
250 if (sock_seqpacket)
251 fd = vsock_seqpacket_accept(VMADDR_CID_ANY, port: opts->peer_port, NULL);
252 else
253 fd = vsock_stream_accept(VMADDR_CID_ANY, port: opts->peer_port, NULL);
254
255 if (fd < 0) {
256 perror("accept");
257 exit(EXIT_FAILURE);
258 }
259
260 data_len = iovec_bytes(iov: test_data->vecs, iovnum: test_data->vecs_cnt);
261
262 data = malloc(data_len);
263 if (!data) {
264 perror("malloc");
265 exit(EXIT_FAILURE);
266 }
267
268 total_bytes_rec = 0;
269
270 while (total_bytes_rec != data_len) {
271 ssize_t bytes_rec;
272
273 bytes_rec = read(fd, data + total_bytes_rec,
274 data_len - total_bytes_rec);
275 if (bytes_rec <= 0)
276 break;
277
278 total_bytes_rec += bytes_rec;
279 }
280
281 if (test_data->sendmsg_errno == 0)
282 local_hash = hash_djb2(data, len: data_len);
283 else
284 local_hash = 0;
285
286 free(data);
287
288 /* Waiting for some result. */
289 remote_hash = control_readulong();
290 if (remote_hash != local_hash) {
291 fprintf(stderr, "hash mismatch\n");
292 exit(EXIT_FAILURE);
293 }
294
295 control_expectln(str: "DONE");
296 close(fd);
297}
298
299void test_stream_msgzcopy_server(const struct test_opts *opts)
300{
301 int i;
302
303 for (i = 0; i < ARRAY_SIZE(test_data_array); i++)
304 test_server(opts, &test_data_array[i], false);
305}
306
307void test_seqpacket_msgzcopy_server(const struct test_opts *opts)
308{
309 int i;
310
311 for (i = 0; i < ARRAY_SIZE(test_data_array); i++) {
312 if (test_data_array[i].stream_only)
313 continue;
314
315 test_server(opts, &test_data_array[i], true);
316 }
317}
318
319void test_stream_msgzcopy_empty_errq_client(const struct test_opts *opts)
320{
321 struct msghdr msg = { 0 };
322 char cmsg_data[128];
323 ssize_t res;
324 int fd;
325
326 fd = vsock_stream_connect(cid: opts->peer_cid, port: opts->peer_port);
327 if (fd < 0) {
328 perror("connect");
329 exit(EXIT_FAILURE);
330 }
331
332 msg.msg_control = cmsg_data;
333 msg.msg_controllen = sizeof(cmsg_data);
334
335 res = recvmsg(fd, &msg, MSG_ERRQUEUE);
336 if (res != -1) {
337 fprintf(stderr, "expected 'recvmsg(2)' failure, got %zi\n",
338 res);
339 exit(EXIT_FAILURE);
340 }
341
342 control_writeln(str: "DONE");
343 close(fd);
344}
345
346void test_stream_msgzcopy_empty_errq_server(const struct test_opts *opts)
347{
348 int fd;
349
350 fd = vsock_stream_accept(VMADDR_CID_ANY, port: opts->peer_port, NULL);
351 if (fd < 0) {
352 perror("accept");
353 exit(EXIT_FAILURE);
354 }
355
356 control_expectln(str: "DONE");
357 close(fd);
358}
359

source code of linux/tools/testing/vsock/vsock_test_zerocopy.c