1 /* SPDX-License-Identifier: MIT */
2 /*
3 * Description: test reading provided ring buf head
4 *
5 */
6 #include <errno.h>
7 #include <stdio.h>
8 #include <unistd.h>
9 #include <stdlib.h>
10 #include <string.h>
11 #include <fcntl.h>
12
13 #include "liburing.h"
14 #include "helpers.h"
15
16 #define BUF_SIZE 32
17 #define NR_BUFS 8
18 #define FSIZE (BUF_SIZE * NR_BUFS)
19
20 #define BR_MASK (NR_BUFS - 1)
21 #define BGID 1
22
23 static int no_buf_ring;
24 static int no_buf_ring_status;
25
test_max(void)26 static int test_max(void)
27 {
28 struct io_uring_buf_ring *br;
29 struct io_uring ring;
30 int nr_bufs = 32768;
31 int ret, i;
32 char *buf;
33
34 ret = io_uring_queue_init(1, &ring, 0);
35 if (ret) {
36 fprintf(stderr, "ring setup failed: %d\n", ret);
37 return 1;
38 }
39
40 if (posix_memalign((void **) &buf, 4096, FSIZE))
41 return 1;
42
43 br = io_uring_setup_buf_ring(&ring, nr_bufs, BGID, 0, &ret);
44 if (!br) {
45 fprintf(stderr, "Buffer ring register failed %d\n", ret);
46 return 1;
47 }
48
49 ret = io_uring_buf_ring_available(&ring, br, BGID);
50 if (ret) {
51 fprintf(stderr, "Bad available count %d\n", ret);
52 return 1;
53 }
54
55 for (i = 0; i < nr_bufs / 2; i++)
56 io_uring_buf_ring_add(br, buf, BUF_SIZE, i + 1, nr_bufs - 1, i);
57 io_uring_buf_ring_advance(br, nr_bufs / 2);
58
59 ret = io_uring_buf_ring_available(&ring, br, BGID);
60 if (ret != nr_bufs / 2) {
61 fprintf(stderr, "Bad half full available count %d\n", ret);
62 return 1;
63 }
64
65 for (i = 0; i < nr_bufs / 2; i++)
66 io_uring_buf_ring_add(br, buf, BUF_SIZE, i + 1, nr_bufs - 1, i);
67 io_uring_buf_ring_advance(br, nr_bufs / 2);
68
69 ret = io_uring_buf_ring_available(&ring, br, BGID);
70 if (ret != nr_bufs) {
71 fprintf(stderr, "Bad half full available count %d\n", ret);
72 return 1;
73 }
74
75 free(buf);
76 io_uring_queue_exit(&ring);
77 return T_EXIT_PASS;
78 }
79
test(int invalid)80 static int test(int invalid)
81 {
82 struct io_uring_sqe *sqe;
83 struct io_uring_cqe *cqe;
84 struct io_uring ring;
85 struct io_uring_buf_ring *br;
86 int ret, i, fds[2];
87 uint16_t head;
88 char *buf;
89 void *ptr;
90 char output[16];
91
92 memset(output, 0x55, sizeof(output));
93
94 ret = io_uring_queue_init(NR_BUFS, &ring, 0);
95 if (ret) {
96 fprintf(stderr, "ring setup failed: %d\n", ret);
97 return 1;
98 }
99
100 if (pipe(fds) < 0) {
101 perror("pipe");
102 return T_EXIT_FAIL;
103 }
104
105 if (posix_memalign((void **) &buf, 4096, FSIZE))
106 return 1;
107
108 br = io_uring_setup_buf_ring(&ring, NR_BUFS, BGID, 0, &ret);
109 if (!br) {
110 if (ret == -EINVAL) {
111 no_buf_ring = 1;
112 free(buf);
113 return 0;
114 }
115 fprintf(stderr, "Buffer ring register failed %d\n", ret);
116 return 1;
117 }
118
119 ptr = buf;
120 for (i = 0; i < NR_BUFS; i++) {
121 io_uring_buf_ring_add(br, ptr, BUF_SIZE, i + 1, BR_MASK, i);
122 ptr += BUF_SIZE;
123 }
124 io_uring_buf_ring_advance(br, NR_BUFS);
125
126 /* head should be zero at this point */
127 head = 1;
128 if (!invalid)
129 ret = io_uring_buf_ring_head(&ring, BGID, &head);
130 else
131 ret = io_uring_buf_ring_head(&ring, BGID + 10, &head);
132 if (ret) {
133 if (ret == -EINVAL) {
134 no_buf_ring_status = 1;
135 free(buf);
136 return T_EXIT_SKIP;
137 }
138 if (invalid && ret == -ENOENT) {
139 free(buf);
140 return T_EXIT_PASS;
141 }
142 fprintf(stderr, "buf_ring_head: %d\n", ret);
143 return T_EXIT_FAIL;
144 }
145 if (invalid) {
146 fprintf(stderr, "lookup of bad group id succeeded\n");
147 return T_EXIT_FAIL;
148 }
149 if (head != 0) {
150 fprintf(stderr, "bad head %d\n", head);
151 return T_EXIT_FAIL;
152 }
153
154 ret = io_uring_buf_ring_available(&ring, br, BGID);
155 if (ret != NR_BUFS) {
156 fprintf(stderr, "ring available %d\n", ret);
157 return T_EXIT_FAIL;
158 }
159
160 sqe = io_uring_get_sqe(&ring);
161 io_uring_prep_read(sqe, fds[0], NULL, BUF_SIZE, i * BUF_SIZE);
162 sqe->buf_group = BGID;
163 sqe->flags |= IOSQE_BUFFER_SELECT;
164 sqe->user_data = 1;
165
166 ret = io_uring_submit(&ring);
167 if (ret != 1) {
168 fprintf(stderr, "submit: %d\n", ret);
169 return T_EXIT_FAIL;
170 }
171
172 /* head should still be zero at this point, no buffers consumed */
173 head = 1;
174 ret = io_uring_buf_ring_head(&ring, BGID, &head);
175 if (head != 0) {
176 fprintf(stderr, "bad head after submit %d\n", head);
177 return T_EXIT_FAIL;
178 }
179
180 ret = write(fds[1], output, sizeof(output));
181 if (ret != sizeof(output)) {
182 fprintf(stderr, "pipe buffer write %d\n", ret);
183 return T_EXIT_FAIL;
184 }
185
186 ret = io_uring_wait_cqe(&ring, &cqe);
187 if (ret) {
188 fprintf(stderr, "wait cqe failed %d\n", ret);
189 return T_EXIT_FAIL;
190 }
191 if (cqe->res != sizeof(output)) {
192 fprintf(stderr, "cqe res %d\n", cqe->res);
193 return T_EXIT_FAIL;
194 }
195 if (!(cqe->flags & IORING_CQE_F_BUFFER)) {
196 fprintf(stderr, "no buffer selected\n");
197 return T_EXIT_FAIL;
198 }
199 io_uring_cqe_seen(&ring, cqe);
200
201 /* head should now be one, we consumed a buffer */
202 ret = io_uring_buf_ring_head(&ring, BGID, &head);
203 if (head != 1) {
204 fprintf(stderr, "bad head after cqe %d\n", head);
205 return T_EXIT_FAIL;
206 }
207
208 ret = io_uring_buf_ring_available(&ring, br, BGID);
209 if (ret != NR_BUFS - 1) {
210 fprintf(stderr, "ring available %d\n", ret);
211 return T_EXIT_FAIL;
212 }
213
214 close(fds[0]);
215 close(fds[1]);
216 free(buf);
217 io_uring_queue_exit(&ring);
218 return T_EXIT_PASS;
219 }
220
main(int argc,char * argv[])221 int main(int argc, char *argv[])
222 {
223 int ret;
224
225 ret = test(0);
226 if (ret == T_EXIT_FAIL) {
227 fprintf(stderr, "test 0 failed\n");
228 return T_EXIT_FAIL;
229 }
230 if (no_buf_ring || no_buf_ring_status)
231 return T_EXIT_SKIP;
232
233 ret = test(1);
234 if (ret == T_EXIT_FAIL) {
235 fprintf(stderr, "test 1 failed\n");
236 return T_EXIT_FAIL;
237 }
238
239 ret = test_max();
240 if (ret == T_EXIT_FAIL) {
241 fprintf(stderr, "test_max failed\n");
242 return T_EXIT_FAIL;
243 }
244
245 return T_EXIT_PASS;
246 }
247