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