xref: /linux/tools/virtio/virtio_test.c (revision 02680c23d7b3febe45ea3d4f9818c2b2dc89020a)
1 // SPDX-License-Identifier: GPL-2.0
2 #define _GNU_SOURCE
3 #include <getopt.h>
4 #include <limits.h>
5 #include <string.h>
6 #include <poll.h>
7 #include <sys/eventfd.h>
8 #include <stdlib.h>
9 #include <assert.h>
10 #include <unistd.h>
11 #include <sys/ioctl.h>
12 #include <sys/stat.h>
13 #include <sys/types.h>
14 #include <fcntl.h>
15 #include <stdbool.h>
16 #include <linux/virtio_types.h>
17 #include <linux/vhost.h>
18 #include <linux/virtio.h>
19 #include <linux/virtio_ring.h>
20 #include "../../drivers/vhost/test.h"
21 
22 #define RANDOM_BATCH -1
23 
24 /* Unused */
25 void *__kmalloc_fake, *__kfree_ignore_start, *__kfree_ignore_end;
26 
27 struct vq_info {
28 	int kick;
29 	int call;
30 	int num;
31 	int idx;
32 	void *ring;
33 	/* copy used for control */
34 	struct vring vring;
35 	struct virtqueue *vq;
36 };
37 
38 struct vdev_info {
39 	struct virtio_device vdev;
40 	int control;
41 	struct pollfd fds[1];
42 	struct vq_info vqs[1];
43 	int nvqs;
44 	void *buf;
45 	size_t buf_size;
46 	struct vhost_memory *mem;
47 };
48 
49 static const struct vhost_vring_file no_backend = { .fd = -1 },
50 				     backend = { .fd = 1 };
51 static const struct vhost_vring_state null_state = {};
52 
53 bool vq_notify(struct virtqueue *vq)
54 {
55 	struct vq_info *info = vq->priv;
56 	unsigned long long v = 1;
57 	int r;
58 	r = write(info->kick, &v, sizeof v);
59 	assert(r == sizeof v);
60 	return true;
61 }
62 
63 void vq_callback(struct virtqueue *vq)
64 {
65 }
66 
67 
68 void vhost_vq_setup(struct vdev_info *dev, struct vq_info *info)
69 {
70 	struct vhost_vring_state state = { .index = info->idx };
71 	struct vhost_vring_file file = { .index = info->idx };
72 	unsigned long long features = dev->vdev.features;
73 	struct vhost_vring_addr addr = {
74 		.index = info->idx,
75 		.desc_user_addr = (uint64_t)(unsigned long)info->vring.desc,
76 		.avail_user_addr = (uint64_t)(unsigned long)info->vring.avail,
77 		.used_user_addr = (uint64_t)(unsigned long)info->vring.used,
78 	};
79 	int r;
80 	r = ioctl(dev->control, VHOST_SET_FEATURES, &features);
81 	assert(r >= 0);
82 	state.num = info->vring.num;
83 	r = ioctl(dev->control, VHOST_SET_VRING_NUM, &state);
84 	assert(r >= 0);
85 	state.num = 0;
86 	r = ioctl(dev->control, VHOST_SET_VRING_BASE, &state);
87 	assert(r >= 0);
88 	r = ioctl(dev->control, VHOST_SET_VRING_ADDR, &addr);
89 	assert(r >= 0);
90 	file.fd = info->kick;
91 	r = ioctl(dev->control, VHOST_SET_VRING_KICK, &file);
92 	assert(r >= 0);
93 	file.fd = info->call;
94 	r = ioctl(dev->control, VHOST_SET_VRING_CALL, &file);
95 	assert(r >= 0);
96 }
97 
98 static void vq_reset(struct vq_info *info, int num, struct virtio_device *vdev)
99 {
100 	if (info->vq)
101 		vring_del_virtqueue(info->vq);
102 
103 	memset(info->ring, 0, vring_size(num, 4096));
104 	vring_init(&info->vring, num, info->ring, 4096);
105 	info->vq = __vring_new_virtqueue(info->idx, info->vring, vdev, true,
106 					 false, vq_notify, vq_callback, "test");
107 	assert(info->vq);
108 	info->vq->priv = info;
109 }
110 
111 static void vq_info_add(struct vdev_info *dev, int num)
112 {
113 	struct vq_info *info = &dev->vqs[dev->nvqs];
114 	int r;
115 	info->idx = dev->nvqs;
116 	info->kick = eventfd(0, EFD_NONBLOCK);
117 	info->call = eventfd(0, EFD_NONBLOCK);
118 	r = posix_memalign(&info->ring, 4096, vring_size(num, 4096));
119 	assert(r >= 0);
120 	vq_reset(info, num, &dev->vdev);
121 	vhost_vq_setup(dev, info);
122 	dev->fds[info->idx].fd = info->call;
123 	dev->fds[info->idx].events = POLLIN;
124 	dev->nvqs++;
125 }
126 
127 static void vdev_info_init(struct vdev_info* dev, unsigned long long features)
128 {
129 	int r;
130 	memset(dev, 0, sizeof *dev);
131 	dev->vdev.features = features;
132 	INIT_LIST_HEAD(&dev->vdev.vqs);
133 	dev->buf_size = 1024;
134 	dev->buf = malloc(dev->buf_size);
135 	assert(dev->buf);
136         dev->control = open("/dev/vhost-test", O_RDWR);
137 	assert(dev->control >= 0);
138 	r = ioctl(dev->control, VHOST_SET_OWNER, NULL);
139 	assert(r >= 0);
140 	dev->mem = malloc(offsetof(struct vhost_memory, regions) +
141 			  sizeof dev->mem->regions[0]);
142 	assert(dev->mem);
143 	memset(dev->mem, 0, offsetof(struct vhost_memory, regions) +
144                           sizeof dev->mem->regions[0]);
145 	dev->mem->nregions = 1;
146 	dev->mem->regions[0].guest_phys_addr = (long)dev->buf;
147 	dev->mem->regions[0].userspace_addr = (long)dev->buf;
148 	dev->mem->regions[0].memory_size = dev->buf_size;
149 	r = ioctl(dev->control, VHOST_SET_MEM_TABLE, dev->mem);
150 	assert(r >= 0);
151 }
152 
153 /* TODO: this is pretty bad: we get a cache line bounce
154  * for the wait queue on poll and another one on read,
155  * plus the read which is there just to clear the
156  * current state. */
157 static void wait_for_interrupt(struct vdev_info *dev)
158 {
159 	int i;
160 	unsigned long long val;
161 	poll(dev->fds, dev->nvqs, -1);
162 	for (i = 0; i < dev->nvqs; ++i)
163 		if (dev->fds[i].revents & POLLIN) {
164 			read(dev->fds[i].fd, &val, sizeof val);
165 		}
166 }
167 
168 static void run_test(struct vdev_info *dev, struct vq_info *vq,
169 		     bool delayed, int batch, int reset_n, int bufs)
170 {
171 	struct scatterlist sl;
172 	long started = 0, completed = 0, next_reset = reset_n;
173 	long completed_before, started_before;
174 	int r, test = 1;
175 	unsigned len;
176 	long long spurious = 0;
177 	const bool random_batch = batch == RANDOM_BATCH;
178 
179 	r = ioctl(dev->control, VHOST_TEST_RUN, &test);
180 	assert(r >= 0);
181 	if (!reset_n) {
182 		next_reset = INT_MAX;
183 	}
184 
185 	for (;;) {
186 		virtqueue_disable_cb(vq->vq);
187 		completed_before = completed;
188 		started_before = started;
189 		do {
190 			const bool reset = completed > next_reset;
191 			if (random_batch)
192 				batch = (random() % vq->vring.num) + 1;
193 
194 			while (started < bufs &&
195 			       (started - completed) < batch) {
196 				sg_init_one(&sl, dev->buf, dev->buf_size);
197 				r = virtqueue_add_outbuf(vq->vq, &sl, 1,
198 							 dev->buf + started,
199 							 GFP_ATOMIC);
200 				if (unlikely(r != 0)) {
201 					if (r == -ENOSPC &&
202 					    started > started_before)
203 						r = 0;
204 					else
205 						r = -1;
206 					break;
207 				}
208 
209 				++started;
210 
211 				if (unlikely(!virtqueue_kick(vq->vq))) {
212 					r = -1;
213 					break;
214 				}
215 			}
216 
217 			if (started >= bufs)
218 				r = -1;
219 
220 			if (reset) {
221 				r = ioctl(dev->control, VHOST_TEST_SET_BACKEND,
222 					  &no_backend);
223 				assert(!r);
224 			}
225 
226 			/* Flush out completed bufs if any */
227 			while (virtqueue_get_buf(vq->vq, &len)) {
228 				++completed;
229 				r = 0;
230 			}
231 
232 			if (reset) {
233 				struct vhost_vring_state s = { .index = 0 };
234 
235 				vq_reset(vq, vq->vring.num, &dev->vdev);
236 
237 				r = ioctl(dev->control, VHOST_GET_VRING_BASE,
238 					  &s);
239 				assert(!r);
240 
241 				s.num = 0;
242 				r = ioctl(dev->control, VHOST_SET_VRING_BASE,
243 					  &null_state);
244 				assert(!r);
245 
246 				r = ioctl(dev->control, VHOST_TEST_SET_BACKEND,
247 					  &backend);
248 				assert(!r);
249 
250 				started = completed;
251 				while (completed > next_reset)
252 					next_reset += completed;
253 			}
254 		} while (r == 0);
255 		if (completed == completed_before && started == started_before)
256 			++spurious;
257 		assert(completed <= bufs);
258 		assert(started <= bufs);
259 		if (completed == bufs)
260 			break;
261 		if (delayed) {
262 			if (virtqueue_enable_cb_delayed(vq->vq))
263 				wait_for_interrupt(dev);
264 		} else {
265 			if (virtqueue_enable_cb(vq->vq))
266 				wait_for_interrupt(dev);
267 		}
268 	}
269 	test = 0;
270 	r = ioctl(dev->control, VHOST_TEST_RUN, &test);
271 	assert(r >= 0);
272 	fprintf(stderr,
273 		"spurious wakeups: 0x%llx started=0x%lx completed=0x%lx\n",
274 		spurious, started, completed);
275 }
276 
277 const char optstring[] = "h";
278 const struct option longopts[] = {
279 	{
280 		.name = "help",
281 		.val = 'h',
282 	},
283 	{
284 		.name = "event-idx",
285 		.val = 'E',
286 	},
287 	{
288 		.name = "no-event-idx",
289 		.val = 'e',
290 	},
291 	{
292 		.name = "indirect",
293 		.val = 'I',
294 	},
295 	{
296 		.name = "no-indirect",
297 		.val = 'i',
298 	},
299 	{
300 		.name = "virtio-1",
301 		.val = '1',
302 	},
303 	{
304 		.name = "no-virtio-1",
305 		.val = '0',
306 	},
307 	{
308 		.name = "delayed-interrupt",
309 		.val = 'D',
310 	},
311 	{
312 		.name = "no-delayed-interrupt",
313 		.val = 'd',
314 	},
315 	{
316 		.name = "batch",
317 		.val = 'b',
318 		.has_arg = required_argument,
319 	},
320 	{
321 		.name = "reset",
322 		.val = 'r',
323 		.has_arg = optional_argument,
324 	},
325 	{
326 	}
327 };
328 
329 static void help(void)
330 {
331 	fprintf(stderr, "Usage: virtio_test [--help]"
332 		" [--no-indirect]"
333 		" [--no-event-idx]"
334 		" [--no-virtio-1]"
335 		" [--delayed-interrupt]"
336 		" [--batch=random/N]"
337 		" [--reset=N]"
338 		"\n");
339 }
340 
341 int main(int argc, char **argv)
342 {
343 	struct vdev_info dev;
344 	unsigned long long features = (1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
345 		(1ULL << VIRTIO_RING_F_EVENT_IDX) | (1ULL << VIRTIO_F_VERSION_1);
346 	long batch = 1, reset = 0;
347 	int o;
348 	bool delayed = false;
349 
350 	for (;;) {
351 		o = getopt_long(argc, argv, optstring, longopts, NULL);
352 		switch (o) {
353 		case -1:
354 			goto done;
355 		case '?':
356 			help();
357 			exit(2);
358 		case 'e':
359 			features &= ~(1ULL << VIRTIO_RING_F_EVENT_IDX);
360 			break;
361 		case 'h':
362 			help();
363 			goto done;
364 		case 'i':
365 			features &= ~(1ULL << VIRTIO_RING_F_INDIRECT_DESC);
366 			break;
367 		case '0':
368 			features &= ~(1ULL << VIRTIO_F_VERSION_1);
369 			break;
370 		case 'D':
371 			delayed = true;
372 			break;
373 		case 'b':
374 			if (0 == strcmp(optarg, "random")) {
375 				batch = RANDOM_BATCH;
376 			} else {
377 				batch = strtol(optarg, NULL, 10);
378 				assert(batch > 0);
379 				assert(batch < (long)INT_MAX + 1);
380 			}
381 			break;
382 		case 'r':
383 			if (!optarg) {
384 				reset = 1;
385 			} else {
386 				reset = strtol(optarg, NULL, 10);
387 				assert(reset > 0);
388 				assert(reset < (long)INT_MAX + 1);
389 			}
390 			break;
391 		default:
392 			assert(0);
393 			break;
394 		}
395 	}
396 
397 done:
398 	vdev_info_init(&dev, features);
399 	vq_info_add(&dev, 256);
400 	run_test(&dev, &dev.vqs[0], delayed, batch, reset, 0x100000);
401 	return 0;
402 }
403