Root/tools/virtio/virtio_test.c

1#define _GNU_SOURCE
2#include <getopt.h>
3#include <string.h>
4#include <poll.h>
5#include <sys/eventfd.h>
6#include <stdlib.h>
7#include <assert.h>
8#include <unistd.h>
9#include <sys/ioctl.h>
10#include <sys/stat.h>
11#include <sys/types.h>
12#include <fcntl.h>
13#include <linux/vhost.h>
14#include <linux/virtio.h>
15#include <linux/virtio_ring.h>
16#include "../../drivers/vhost/test.h"
17
18struct vq_info {
19    int kick;
20    int call;
21    int num;
22    int idx;
23    void *ring;
24    /* copy used for control */
25    struct vring vring;
26    struct virtqueue *vq;
27};
28
29struct vdev_info {
30    struct virtio_device vdev;
31    int control;
32    struct pollfd fds[1];
33    struct vq_info vqs[1];
34    int nvqs;
35    void *buf;
36    size_t buf_size;
37    struct vhost_memory *mem;
38};
39
40void vq_notify(struct virtqueue *vq)
41{
42    struct vq_info *info = vq->priv;
43    unsigned long long v = 1;
44    int r;
45    r = write(info->kick, &v, sizeof v);
46    assert(r == sizeof v);
47}
48
49void vq_callback(struct virtqueue *vq)
50{
51}
52
53
54void vhost_vq_setup(struct vdev_info *dev, struct vq_info *info)
55{
56    struct vhost_vring_state state = { .index = info->idx };
57    struct vhost_vring_file file = { .index = info->idx };
58    unsigned long long features = dev->vdev.features[0];
59    struct vhost_vring_addr addr = {
60        .index = info->idx,
61        .desc_user_addr = (uint64_t)(unsigned long)info->vring.desc,
62        .avail_user_addr = (uint64_t)(unsigned long)info->vring.avail,
63        .used_user_addr = (uint64_t)(unsigned long)info->vring.used,
64    };
65    int r;
66    r = ioctl(dev->control, VHOST_SET_FEATURES, &features);
67    assert(r >= 0);
68    state.num = info->vring.num;
69    r = ioctl(dev->control, VHOST_SET_VRING_NUM, &state);
70    assert(r >= 0);
71    state.num = 0;
72    r = ioctl(dev->control, VHOST_SET_VRING_BASE, &state);
73    assert(r >= 0);
74    r = ioctl(dev->control, VHOST_SET_VRING_ADDR, &addr);
75    assert(r >= 0);
76    file.fd = info->kick;
77    r = ioctl(dev->control, VHOST_SET_VRING_KICK, &file);
78    assert(r >= 0);
79    file.fd = info->call;
80    r = ioctl(dev->control, VHOST_SET_VRING_CALL, &file);
81    assert(r >= 0);
82}
83
84static void vq_info_add(struct vdev_info *dev, int num)
85{
86    struct vq_info *info = &dev->vqs[dev->nvqs];
87    int r;
88    info->idx = dev->nvqs;
89    info->kick = eventfd(0, EFD_NONBLOCK);
90    info->call = eventfd(0, EFD_NONBLOCK);
91    r = posix_memalign(&info->ring, 4096, vring_size(num, 4096));
92    assert(r >= 0);
93    memset(info->ring, 0, vring_size(num, 4096));
94    vring_init(&info->vring, num, info->ring, 4096);
95    info->vq = vring_new_virtqueue(info->vring.num, 4096, &dev->vdev,
96                       true, info->ring,
97                       vq_notify, vq_callback, "test");
98    assert(info->vq);
99    info->vq->priv = info;
100    vhost_vq_setup(dev, info);
101    dev->fds[info->idx].fd = info->call;
102    dev->fds[info->idx].events = POLLIN;
103    dev->nvqs++;
104}
105
106static void vdev_info_init(struct vdev_info* dev, unsigned long long features)
107{
108    int r;
109    memset(dev, 0, sizeof *dev);
110    dev->vdev.features[0] = features;
111    dev->vdev.features[1] = features >> 32;
112    dev->buf_size = 1024;
113    dev->buf = malloc(dev->buf_size);
114    assert(dev->buf);
115        dev->control = open("/dev/vhost-test", O_RDWR);
116    assert(dev->control >= 0);
117    r = ioctl(dev->control, VHOST_SET_OWNER, NULL);
118    assert(r >= 0);
119    dev->mem = malloc(offsetof(struct vhost_memory, regions) +
120              sizeof dev->mem->regions[0]);
121    assert(dev->mem);
122    memset(dev->mem, 0, offsetof(struct vhost_memory, regions) +
123                          sizeof dev->mem->regions[0]);
124    dev->mem->nregions = 1;
125    dev->mem->regions[0].guest_phys_addr = (long)dev->buf;
126    dev->mem->regions[0].userspace_addr = (long)dev->buf;
127    dev->mem->regions[0].memory_size = dev->buf_size;
128    r = ioctl(dev->control, VHOST_SET_MEM_TABLE, dev->mem);
129    assert(r >= 0);
130}
131
132/* TODO: this is pretty bad: we get a cache line bounce
133 * for the wait queue on poll and another one on read,
134 * plus the read which is there just to clear the
135 * current state. */
136static void wait_for_interrupt(struct vdev_info *dev)
137{
138    int i;
139    unsigned long long val;
140    poll(dev->fds, dev->nvqs, -1);
141    for (i = 0; i < dev->nvqs; ++i)
142        if (dev->fds[i].revents & POLLIN) {
143            read(dev->fds[i].fd, &val, sizeof val);
144        }
145}
146
147static void run_test(struct vdev_info *dev, struct vq_info *vq,
148             bool delayed, int bufs)
149{
150    struct scatterlist sl;
151    long started = 0, completed = 0;
152    long completed_before;
153    int r, test = 1;
154    unsigned len;
155    long long spurious = 0;
156    r = ioctl(dev->control, VHOST_TEST_RUN, &test);
157    assert(r >= 0);
158    for (;;) {
159        virtqueue_disable_cb(vq->vq);
160        completed_before = completed;
161        do {
162            if (started < bufs) {
163                sg_init_one(&sl, dev->buf, dev->buf_size);
164                r = virtqueue_add_buf(vq->vq, &sl, 1, 0,
165                              dev->buf + started,
166                              GFP_ATOMIC);
167                if (likely(r >= 0)) {
168                    ++started;
169                    virtqueue_kick(vq->vq);
170                }
171            } else
172                r = -1;
173
174            /* Flush out completed bufs if any */
175            if (virtqueue_get_buf(vq->vq, &len)) {
176                ++completed;
177                r = 0;
178            }
179
180        } while (r >= 0);
181        if (completed == completed_before)
182            ++spurious;
183        assert(completed <= bufs);
184        assert(started <= bufs);
185        if (completed == bufs)
186            break;
187        if (delayed) {
188            if (virtqueue_enable_cb_delayed(vq->vq))
189                wait_for_interrupt(dev);
190        } else {
191            if (virtqueue_enable_cb(vq->vq))
192                wait_for_interrupt(dev);
193        }
194    }
195    test = 0;
196    r = ioctl(dev->control, VHOST_TEST_RUN, &test);
197    assert(r >= 0);
198    fprintf(stderr, "spurious wakeus: 0x%llx\n", spurious);
199}
200
201const char optstring[] = "h";
202const struct option longopts[] = {
203    {
204        .name = "help",
205        .val = 'h',
206    },
207    {
208        .name = "event-idx",
209        .val = 'E',
210    },
211    {
212        .name = "no-event-idx",
213        .val = 'e',
214    },
215    {
216        .name = "indirect",
217        .val = 'I',
218    },
219    {
220        .name = "no-indirect",
221        .val = 'i',
222    },
223    {
224        .name = "delayed-interrupt",
225        .val = 'D',
226    },
227    {
228        .name = "no-delayed-interrupt",
229        .val = 'd',
230    },
231    {
232    }
233};
234
235static void help()
236{
237    fprintf(stderr, "Usage: virtio_test [--help]"
238        " [--no-indirect]"
239        " [--no-event-idx]"
240        " [--delayed-interrupt]"
241        "\n");
242}
243
244int main(int argc, char **argv)
245{
246    struct vdev_info dev;
247    unsigned long long features = (1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
248        (1ULL << VIRTIO_RING_F_EVENT_IDX);
249    int o;
250    bool delayed = false;
251
252    for (;;) {
253        o = getopt_long(argc, argv, optstring, longopts, NULL);
254        switch (o) {
255        case -1:
256            goto done;
257        case '?':
258            help();
259            exit(2);
260        case 'e':
261            features &= ~(1ULL << VIRTIO_RING_F_EVENT_IDX);
262            break;
263        case 'h':
264            help();
265            goto done;
266        case 'i':
267            features &= ~(1ULL << VIRTIO_RING_F_INDIRECT_DESC);
268            break;
269        case 'D':
270            delayed = true;
271            break;
272        default:
273            assert(0);
274            break;
275        }
276    }
277
278done:
279    vdev_info_init(&dev, features);
280    vq_info_add(&dev, 256);
281    run_test(&dev, &dev.vqs[0], delayed, 0x100000);
282    return 0;
283}
284

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