tests/libqos/virtio.c

   1 /*
   2  * libqos virtio driver
   3  *
   4  * Copyright (c) 2014 Marc Marí
   5  *
   6  * This work is licensed under the terms of the GNU GPL, version 2 or later.
   7  * See the COPYING file in the top-level directory.
   8  */
   9
  10 #include "qemu/osdep.h"
  11 #include "libqtest.h"
  12 #include "libqos/virtio.h"
  13 #include "standard-headers/linux/virtio_config.h"
  14 #include "standard-headers/linux/virtio_ring.h"
  15
  16 uint8_t qvirtio_config_readb(QVirtioDevice *d, uint64_t addr)
  17 {
  18     return d->bus->config_readb(d, addr);
  19 }
  20
  21 uint16_t qvirtio_config_readw(QVirtioDevice *d, uint64_t addr)
  22 {
  23     return d->bus->config_readw(d, addr);
  24 }
  25
  26 uint32_t qvirtio_config_readl(QVirtioDevice *d, uint64_t addr)
  27 {
  28     return d->bus->config_readl(d, addr);
  29 }
  30
  31 uint64_t qvirtio_config_readq(QVirtioDevice *d, uint64_t addr)
  32 {
  33     return d->bus->config_readq(d, addr);
  34 }
  35
  36 uint32_t qvirtio_get_features(QVirtioDevice *d)
  37 {
  38     return d->bus->get_features(d);
  39 }
  40
  41 void qvirtio_set_features(QVirtioDevice *d, uint32_t features)
  42 {
  43     d->features = features;
  44     d->bus->set_features(d, features);
  45 }
  46
  47 QVirtQueue *qvirtqueue_setup(QVirtioDevice *d,
  48                              QGuestAllocator *alloc, uint16_t index)
  49 {
  50     return d->bus->virtqueue_setup(d, alloc, index);
  51 }
  52
  53 void qvirtqueue_cleanup(const QVirtioBus *bus, QVirtQueue *vq,
  54                         QGuestAllocator *alloc)
  55 {
  56     return bus->virtqueue_cleanup(vq, alloc);
  57 }
  58
  59 void qvirtio_reset(QVirtioDevice *d)
  60 {
  61     d->bus->set_status(d, 0);
  62     g_assert_cmphex(d->bus->get_status(d), ==, 0);
  63 }
  64
  65 void qvirtio_set_acknowledge(QVirtioDevice *d)
  66 {
  67     d->bus->set_status(d, d->bus->get_status(d) | VIRTIO_CONFIG_S_ACKNOWLEDGE);
  68     g_assert_cmphex(d->bus->get_status(d), ==, VIRTIO_CONFIG_S_ACKNOWLEDGE);
  69 }
  70
  71 void qvirtio_set_driver(QVirtioDevice *d)
  72 {
  73     d->bus->set_status(d, d->bus->get_status(d) | VIRTIO_CONFIG_S_DRIVER);
  74     g_assert_cmphex(d->bus->get_status(d), ==,
  75                     VIRTIO_CONFIG_S_DRIVER | VIRTIO_CONFIG_S_ACKNOWLEDGE);
  76 }
  77
  78 void qvirtio_set_driver_ok(QVirtioDevice *d)
  79 {
  80     d->bus->set_status(d, d->bus->get_status(d) | VIRTIO_CONFIG_S_DRIVER_OK);
  81     g_assert_cmphex(d->bus->get_status(d), ==, VIRTIO_CONFIG_S_DRIVER_OK |
  82                     VIRTIO_CONFIG_S_DRIVER | VIRTIO_CONFIG_S_ACKNOWLEDGE);
  83 }
  84
  85 void qvirtio_wait_queue_isr(QVirtioDevice *d,
  86                             QVirtQueue *vq, gint64 timeout_us)
  87 {
  88     gint64 start_time = g_get_monotonic_time();
  89
  90     for (;;) {
  91         clock_step(100);
  92         if (d->bus->get_queue_isr_status(d, vq)) {
  93             return;
  94         }
  95         g_assert(g_get_monotonic_time() - start_time <= timeout_us);
  96     }
  97 }
  98
  99 /* Wait for the status byte at given guest memory address to be set
 100  *
 101  * The virtqueue interrupt must not be raised, making this useful for testing
 102  * event_index functionality.
 103  */
 104 uint8_t qvirtio_wait_status_byte_no_isr(QVirtioDevice *d,
 105                                         QVirtQueue *vq,
 106                                         uint64_t addr,
 107                                         gint64 timeout_us)
 108 {
 109     gint64 start_time = g_get_monotonic_time();
 110     uint8_t val;
 111
 112     while ((val = readb(addr)) == 0xff) {
 113         clock_step(100);
 114         g_assert(!d->bus->get_queue_isr_status(d, vq));
 115         g_assert(g_get_monotonic_time() - start_time <= timeout_us);
 116     }
 117     return val;
 118 }
 119
 120 /*
 121  * qvirtio_wait_used_elem:
 122  * @desc_idx: The next expected vq->desc[] index in the used ring
 123  * @len: A pointer that is filled with the length written into the buffer, may
 124  *       be NULL
 125  * @timeout_us: How many microseconds to wait before failing
 126  *
 127  * This function waits for the next completed request on the used ring.
 128  */
 129 void qvirtio_wait_used_elem(QVirtioDevice *d,
 130                             QVirtQueue *vq,
 131                             uint32_t desc_idx,
 132                             uint32_t *len,
 133                             gint64 timeout_us)
 134 {
 135     gint64 start_time = g_get_monotonic_time();
 136
 137     for (;;) {
 138         uint32_t got_desc_idx;
 139
 140         clock_step(100);
 141
 142         if (d->bus->get_queue_isr_status(d, vq) &&
 143             qvirtqueue_get_buf(vq, &got_desc_idx, len)) {
 144             g_assert_cmpint(got_desc_idx, ==, desc_idx);
 145             return;
 146         }
 147
 148         g_assert(g_get_monotonic_time() - start_time <= timeout_us);
 149     }
 150 }
 151
 152 void qvirtio_wait_config_isr(QVirtioDevice *d, gint64 timeout_us)
 153 {
 154     gint64 start_time = g_get_monotonic_time();
 155
 156     for (;;) {
 157         clock_step(100);
 158         if (d->bus->get_config_isr_status(d)) {
 159             return;
 160         }
 161         g_assert(g_get_monotonic_time() - start_time <= timeout_us);
 162     }
 163 }
 164
 165 void qvring_init(QTestState *qts, const QGuestAllocator *alloc, QVirtQueue *vq,
 166                  uint64_t addr)
 167 {
 168     int i;
 169
 170     vq->desc = addr;
 171     vq->avail = vq->desc + vq->size * sizeof(struct vring_desc);
 172     vq->used = (uint64_t)((vq->avail + sizeof(uint16_t) * (3 + vq->size)
 173         + vq->align - 1) & ~(vq->align - 1));
 174
 175     for (i = 0; i < vq->size - 1; i++) {
 176         /* vq->desc[i].addr */
 177         qtest_writeq(qts, vq->desc + (16 * i), 0);
 178         /* vq->desc[i].next */
 179         qtest_writew(qts, vq->desc + (16 * i) + 14, i + 1);
 180     }
 181
 182     /* vq->avail->flags */
 183     qtest_writew(qts, vq->avail, 0);
 184     /* vq->avail->idx */
 185     qtest_writew(qts, vq->avail + 2, 0);
 186     /* vq->avail->used_event */
 187     qtest_writew(qts, vq->avail + 4 + (2 * vq->size), 0);
 188
 189     /* vq->used->flags */
 190     qtest_writew(qts, vq->used, 0);
 191     /* vq->used->avail_event */
 192     qtest_writew(qts, vq->used + 2 + sizeof(struct vring_used_elem) * vq->size,
 193                  0);
 194 }
 195
 196 QVRingIndirectDesc *qvring_indirect_desc_setup(QVirtioDevice *d,
 197                                         QGuestAllocator *alloc, uint16_t elem)
 198 {
 199     int i;
 200     QVRingIndirectDesc *indirect = g_malloc(sizeof(*indirect));
 201
 202     indirect->index = 0;
 203     indirect->elem = elem;
 204     indirect->desc = guest_alloc(alloc, sizeof(struct vring_desc) * elem);
 205
 206     for (i = 0; i < elem - 1; ++i) {
 207         /* indirect->desc[i].addr */
 208         writeq(indirect->desc + (16 * i), 0);
 209         /* indirect->desc[i].flags */
 210         writew(indirect->desc + (16 * i) + 12, VRING_DESC_F_NEXT);
 211         /* indirect->desc[i].next */
 212         writew(indirect->desc + (16 * i) + 14, i + 1);
 213     }
 214
 215     return indirect;
 216 }
 217
 218 void qvring_indirect_desc_add(QVRingIndirectDesc *indirect, uint64_t data,
 219                                                     uint32_t len, bool write)
 220 {
 221     uint16_t flags;
 222
 223     g_assert_cmpint(indirect->index, <, indirect->elem);
 224
 225     flags = readw(indirect->desc + (16 * indirect->index) + 12);
 226
 227     if (write) {
 228         flags |= VRING_DESC_F_WRITE;
 229     }
 230
 231     /* indirect->desc[indirect->index].addr */
 232     writeq(indirect->desc + (16 * indirect->index), data);
 233     /* indirect->desc[indirect->index].len */
 234     writel(indirect->desc + (16 * indirect->index) + 8, len);
 235     /* indirect->desc[indirect->index].flags */
 236     writew(indirect->desc + (16 * indirect->index) + 12, flags);
 237
 238     indirect->index++;
 239 }
 240
 241 uint32_t qvirtqueue_add(QVirtQueue *vq, uint64_t data, uint32_t len, bool write,
 242                                                                     bool next)
 243 {
 244     uint16_t flags = 0;
 245     vq->num_free--;
 246
 247     if (write) {
 248         flags |= VRING_DESC_F_WRITE;
 249     }
 250
 251     if (next) {
 252         flags |= VRING_DESC_F_NEXT;
 253     }
 254
 255     /* vq->desc[vq->free_head].addr */
 256     writeq(vq->desc + (16 * vq->free_head), data);
 257     /* vq->desc[vq->free_head].len */
 258     writel(vq->desc + (16 * vq->free_head) + 8, len);
 259     /* vq->desc[vq->free_head].flags */
 260     writew(vq->desc + (16 * vq->free_head) + 12, flags);
 261
 262     return vq->free_head++; /* Return and increase, in this order */
 263 }
 264
 265 uint32_t qvirtqueue_add_indirect(QVirtQueue *vq, QVRingIndirectDesc *indirect)
 266 {
 267     g_assert(vq->indirect);
 268     g_assert_cmpint(vq->size, >=, indirect->elem);
 269     g_assert_cmpint(indirect->index, ==, indirect->elem);
 270
 271     vq->num_free--;
 272
 273     /* vq->desc[vq->free_head].addr */
 274     writeq(vq->desc + (16 * vq->free_head), indirect->desc);
 275     /* vq->desc[vq->free_head].len */
 276     writel(vq->desc + (16 * vq->free_head) + 8,
 277            sizeof(struct vring_desc) * indirect->elem);
 278     /* vq->desc[vq->free_head].flags */
 279     writew(vq->desc + (16 * vq->free_head) + 12, VRING_DESC_F_INDIRECT);
 280
 281     return vq->free_head++; /* Return and increase, in this order */
 282 }
 283
 284 void qvirtqueue_kick(QVirtioDevice *d, QVirtQueue *vq, uint32_t free_head)
 285 {
 286     /* vq->avail->idx */
 287     uint16_t idx = readw(vq->avail + 2);
 288     /* vq->used->flags */
 289     uint16_t flags;
 290     /* vq->used->avail_event */
 291     uint16_t avail_event;
 292
 293     /* vq->avail->ring[idx % vq->size] */
 294     writew(vq->avail + 4 + (2 * (idx % vq->size)), free_head);
 295     /* vq->avail->idx */
 296     writew(vq->avail + 2, idx + 1);
 297
 298     /* Must read after idx is updated */
 299     flags = readw(vq->avail);
 300     avail_event = readw(vq->used + 4 +
 301                                 sizeof(struct vring_used_elem) * vq->size);
 302
 303     /* < 1 because we add elements to avail queue one by one */
 304     if ((flags & VRING_USED_F_NO_NOTIFY) == 0 &&
 305                             (!vq->event || (uint16_t)(idx-avail_event) < 1)) {
 306         d->bus->virtqueue_kick(d, vq);
 307     }
 308 }
 309
 310 /*
 311  * qvirtqueue_get_buf:
 312  * @desc_idx: A pointer that is filled with the vq->desc[] index, may be NULL
 313  * @len: A pointer that is filled with the length written into the buffer, may
 314  *       be NULL
 315  *
 316  * This function gets the next used element if there is one ready.
 317  *
 318  * Returns: true if an element was ready, false otherwise
 319  */
 320 bool qvirtqueue_get_buf(QVirtQueue *vq, uint32_t *desc_idx, uint32_t *len)
 321 {
 322     uint16_t idx;
 323     uint64_t elem_addr;
 324
 325     idx = readw(vq->used + offsetof(struct vring_used, idx));
 326     if (idx == vq->last_used_idx) {
 327         return false;
 328     }
 329
 330     elem_addr = vq->used +
 331         offsetof(struct vring_used, ring) +
 332         (vq->last_used_idx % vq->size) *
 333         sizeof(struct vring_used_elem);
 334
 335     if (desc_idx) {
 336         *desc_idx = readl(elem_addr + offsetof(struct vring_used_elem, id));
 337     }
 338
 339     if (len) {
 340         *len = readw(elem_addr + offsetof(struct vring_used_elem, len));
 341     }
 342
 343     vq->last_used_idx++;
 344     return true;
 345 }
 346
 347 void qvirtqueue_set_used_event(QVirtQueue *vq, uint16_t idx)
 348 {
 349     g_assert(vq->event);
 350
 351     /* vq->avail->used_event */
 352     writew(vq->avail + 4 + (2 * vq->size), idx);
 353 }
 354
 355 void qvirtio_start_device(QVirtioDevice *vdev)
 356 {
 357     qvirtio_reset(vdev);
 358     qvirtio_set_acknowledge(vdev);
 359     qvirtio_set_driver(vdev);
 360 }
 361
 362 bool qvirtio_is_big_endian(QVirtioDevice *d)
 363 {
 364     return d->big_endian;
 365 }