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 */
25void *__kmalloc_fake, *__kfree_ignore_start, *__kfree_ignore_end;
26
27struct 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
38struct 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
49static const struct vhost_vring_file no_backend = { .fd = -1 },
50				     backend = { .fd = 1 };
51static const struct vhost_vring_state null_state = {};
52
53bool 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
63void vq_callback(struct virtqueue *vq)
64{
65}
66
67
68void 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
98static 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, num, 4096, vdev, true, false,
106				       info->ring, vq_notify, vq_callback, "test");
107	assert(info->vq);
108	info->vq->priv = info;
109}
110
111static 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
127static 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	spin_lock_init(&dev->vdev.vqs_list_lock);
134	dev->buf_size = 1024;
135	dev->buf = malloc(dev->buf_size);
136	assert(dev->buf);
137	dev->control = open("/dev/vhost-test", O_RDWR);
138	assert(dev->control >= 0);
139	r = ioctl(dev->control, VHOST_SET_OWNER, NULL);
140	assert(r >= 0);
141	dev->mem = malloc(offsetof(struct vhost_memory, regions) +
142			  sizeof dev->mem->regions[0]);
143	assert(dev->mem);
144	memset(dev->mem, 0, offsetof(struct vhost_memory, regions) +
145                          sizeof dev->mem->regions[0]);
146	dev->mem->nregions = 1;
147	dev->mem->regions[0].guest_phys_addr = (long)dev->buf;
148	dev->mem->regions[0].userspace_addr = (long)dev->buf;
149	dev->mem->regions[0].memory_size = dev->buf_size;
150	r = ioctl(dev->control, VHOST_SET_MEM_TABLE, dev->mem);
151	assert(r >= 0);
152}
153
154/* TODO: this is pretty bad: we get a cache line bounce
155 * for the wait queue on poll and another one on read,
156 * plus the read which is there just to clear the
157 * current state. */
158static void wait_for_interrupt(struct vdev_info *dev)
159{
160	int i;
161	unsigned long long val;
162	poll(dev->fds, dev->nvqs, -1);
163	for (i = 0; i < dev->nvqs; ++i)
164		if (dev->fds[i].revents & POLLIN) {
165			read(dev->fds[i].fd, &val, sizeof val);
166		}
167}
168
169static void run_test(struct vdev_info *dev, struct vq_info *vq,
170		     bool delayed, int batch, int reset_n, int bufs)
171{
172	struct scatterlist sl;
173	long started = 0, completed = 0, next_reset = reset_n;
174	long completed_before, started_before;
175	int r, test = 1;
176	unsigned int len;
177	long long spurious = 0;
178	const bool random_batch = batch == RANDOM_BATCH;
179
180	r = ioctl(dev->control, VHOST_TEST_RUN, &test);
181	assert(r >= 0);
182	if (!reset_n) {
183		next_reset = INT_MAX;
184	}
185
186	for (;;) {
187		virtqueue_disable_cb(vq->vq);
188		completed_before = completed;
189		started_before = started;
190		do {
191			const bool reset = completed > next_reset;
192			if (random_batch)
193				batch = (random() % vq->vring.num) + 1;
194
195			while (started < bufs &&
196			       (started - completed) < batch) {
197				sg_init_one(&sl, dev->buf, dev->buf_size);
198				r = virtqueue_add_outbuf(vq->vq, &sl, 1,
199							 dev->buf + started,
200							 GFP_ATOMIC);
201				if (unlikely(r != 0)) {
202					if (r == -ENOSPC &&
203					    started > started_before)
204						r = 0;
205					else
206						r = -1;
207					break;
208				}
209
210				++started;
211
212				if (unlikely(!virtqueue_kick(vq->vq))) {
213					r = -1;
214					break;
215				}
216			}
217
218			if (started >= bufs)
219				r = -1;
220
221			if (reset) {
222				r = ioctl(dev->control, VHOST_TEST_SET_BACKEND,
223					  &no_backend);
224				assert(!r);
225			}
226
227			/* Flush out completed bufs if any */
228			while (virtqueue_get_buf(vq->vq, &len)) {
229				++completed;
230				r = 0;
231			}
232
233			if (reset) {
234				struct vhost_vring_state s = { .index = 0 };
235
236				vq_reset(vq, vq->vring.num, &dev->vdev);
237
238				r = ioctl(dev->control, VHOST_GET_VRING_BASE,
239					  &s);
240				assert(!r);
241
242				s.num = 0;
243				r = ioctl(dev->control, VHOST_SET_VRING_BASE,
244					  &null_state);
245				assert(!r);
246
247				r = ioctl(dev->control, VHOST_TEST_SET_BACKEND,
248					  &backend);
249				assert(!r);
250
251				started = completed;
252				while (completed > next_reset)
253					next_reset += completed;
254			}
255		} while (r == 0);
256		if (completed == completed_before && started == started_before)
257			++spurious;
258		assert(completed <= bufs);
259		assert(started <= bufs);
260		if (completed == bufs)
261			break;
262		if (delayed) {
263			if (virtqueue_enable_cb_delayed(vq->vq))
264				wait_for_interrupt(dev);
265		} else {
266			if (virtqueue_enable_cb(vq->vq))
267				wait_for_interrupt(dev);
268		}
269	}
270	test = 0;
271	r = ioctl(dev->control, VHOST_TEST_RUN, &test);
272	assert(r >= 0);
273	fprintf(stderr,
274		"spurious wakeups: 0x%llx started=0x%lx completed=0x%lx\n",
275		spurious, started, completed);
276}
277
278const char optstring[] = "h";
279const struct option longopts[] = {
280	{
281		.name = "help",
282		.val = 'h',
283	},
284	{
285		.name = "event-idx",
286		.val = 'E',
287	},
288	{
289		.name = "no-event-idx",
290		.val = 'e',
291	},
292	{
293		.name = "indirect",
294		.val = 'I',
295	},
296	{
297		.name = "no-indirect",
298		.val = 'i',
299	},
300	{
301		.name = "virtio-1",
302		.val = '1',
303	},
304	{
305		.name = "no-virtio-1",
306		.val = '0',
307	},
308	{
309		.name = "delayed-interrupt",
310		.val = 'D',
311	},
312	{
313		.name = "no-delayed-interrupt",
314		.val = 'd',
315	},
316	{
317		.name = "batch",
318		.val = 'b',
319		.has_arg = required_argument,
320	},
321	{
322		.name = "reset",
323		.val = 'r',
324		.has_arg = optional_argument,
325	},
326	{
327	}
328};
329
330static void help(int status)
331{
332	fprintf(stderr, "Usage: virtio_test [--help]"
333		" [--no-indirect]"
334		" [--no-event-idx]"
335		" [--no-virtio-1]"
336		" [--delayed-interrupt]"
337		" [--batch=random/N]"
338		" [--reset=N]"
339		"\n");
340
341	exit(status);
342}
343
344int main(int argc, char **argv)
345{
346	struct vdev_info dev;
347	unsigned long long features = (1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
348		(1ULL << VIRTIO_RING_F_EVENT_IDX) | (1ULL << VIRTIO_F_VERSION_1);
349	long batch = 1, reset = 0;
350	int o;
351	bool delayed = false;
352
353	for (;;) {
354		o = getopt_long(argc, argv, optstring, longopts, NULL);
355		switch (o) {
356		case -1:
357			goto done;
358		case '?':
359			help(2);
360		case 'e':
361			features &= ~(1ULL << VIRTIO_RING_F_EVENT_IDX);
362			break;
363		case 'h':
364			help(0);
365		case 'i':
366			features &= ~(1ULL << VIRTIO_RING_F_INDIRECT_DESC);
367			break;
368		case '0':
369			features &= ~(1ULL << VIRTIO_F_VERSION_1);
370			break;
371		case 'D':
372			delayed = true;
373			break;
374		case 'b':
375			if (0 == strcmp(optarg, "random")) {
376				batch = RANDOM_BATCH;
377			} else {
378				batch = strtol(optarg, NULL, 10);
379				assert(batch > 0);
380				assert(batch < (long)INT_MAX + 1);
381			}
382			break;
383		case 'r':
384			if (!optarg) {
385				reset = 1;
386			} else {
387				reset = strtol(optarg, NULL, 10);
388				assert(reset > 0);
389				assert(reset < (long)INT_MAX + 1);
390			}
391			break;
392		default:
393			assert(0);
394			break;
395		}
396	}
397
398done:
399	vdev_info_init(&dev, features);
400	vq_info_add(&dev, 256);
401	run_test(&dev, &dev.vqs[0], delayed, batch, reset, 0x100000);
402	return 0;
403}
404