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, 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 }