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->bus->set_features(d, features);
  44 }
  45
  46 QVirtQueue *qvirtqueue_setup(QVirtioDevice *d,
  47                              QGuestAllocator *alloc, uint16_t index)
  48 {
  49     return d->bus->virtqueue_setup(d, alloc, index);
  50 }
  51
  52 void qvirtqueue_cleanup(const QVirtioBus *bus, QVirtQueue *vq,
  53                         QGuestAllocator *alloc)
  54 {
  55     return bus->virtqueue_cleanup(vq, alloc);
  56 }
  57
  58 void qvirtio_reset(QVirtioDevice *d)
  59 {
  60     d->bus->set_status(d, 0);
  61     g_assert_cmphex(d->bus->get_status(d), ==, 0);
  62 }
  63
  64 void 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
  70 void 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
  77 void 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
  84 void 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  */
 103 uint8_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  */
 126 void 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
 148 void 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
 161 void 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
 190 QVRingIndirectDesc *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
 212 void 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
 235 uint32_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
 259 uint32_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
 278 void 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  */
 312 bool 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
 335 void 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 }