tools/virtio/virtio_test.c

   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, num, 4096, vdev, true, false,
 106                                        info->ring, 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         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. */
 158 static 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
 169 static 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
 278 const char optstring[] = "h";
 279 const 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
 330 static 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
 344 int 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
 398 done:
 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 }