linux/tools/virtio/virtio_test.c
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   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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