xref: /qemu/tests/qtest/libqos/virtio.c (revision a9340358f4d5d0e8e0c7a3a23cb4e5b68334974c)
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 uint64_t qvirtio_get_features(QVirtioDevice *d)
37 {
38     return d->bus->get_features(d);
39 }
40 
41 void qvirtio_set_features(QVirtioDevice *d, uint64_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(QTestState *qts, QVirtioDevice *d,
86                             QVirtQueue *vq, gint64 timeout_us)
87 {
88     gint64 start_time = g_get_monotonic_time();
89 
90     for (;;) {
91         qtest_clock_step(qts, 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(QTestState *qts, 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 = qtest_readb(qts, addr)) == 0xff) {
113         qtest_clock_step(qts, 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(QTestState *qts, 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         qtest_clock_step(qts, 100);
141 
142         if (d->bus->get_queue_isr_status(d, vq) &&
143             qvirtqueue_get_buf(qts, 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     d->bus->wait_config_isr_status(d, timeout_us);
155 }
156 
157 void qvring_init(QTestState *qts, const QGuestAllocator *alloc, QVirtQueue *vq,
158                  uint64_t addr)
159 {
160     int i;
161 
162     vq->desc = addr;
163     vq->avail = vq->desc + vq->size * sizeof(struct vring_desc);
164     vq->used = (uint64_t)((vq->avail + sizeof(uint16_t) * (3 + vq->size)
165         + vq->align - 1) & ~(vq->align - 1));
166 
167     for (i = 0; i < vq->size - 1; i++) {
168         /* vq->desc[i].addr */
169         qtest_writeq(qts, vq->desc + (16 * i), 0);
170         /* vq->desc[i].next */
171         qtest_writew(qts, vq->desc + (16 * i) + 14, i + 1);
172     }
173 
174     /* vq->avail->flags */
175     qtest_writew(qts, vq->avail, 0);
176     /* vq->avail->idx */
177     qtest_writew(qts, vq->avail + 2, 0);
178     /* vq->avail->used_event */
179     qtest_writew(qts, vq->avail + 4 + (2 * vq->size), 0);
180 
181     /* vq->used->flags */
182     qtest_writew(qts, vq->used, 0);
183     /* vq->used->avail_event */
184     qtest_writew(qts, vq->used + 2 + sizeof(struct vring_used_elem) * vq->size,
185                  0);
186 }
187 
188 QVRingIndirectDesc *qvring_indirect_desc_setup(QTestState *qs, QVirtioDevice *d,
189                                                QGuestAllocator *alloc,
190                                                uint16_t elem)
191 {
192     int i;
193     QVRingIndirectDesc *indirect = g_malloc(sizeof(*indirect));
194 
195     indirect->index = 0;
196     indirect->elem = elem;
197     indirect->desc = guest_alloc(alloc, sizeof(struct vring_desc) * elem);
198 
199     for (i = 0; i < elem - 1; ++i) {
200         /* indirect->desc[i].addr */
201         qtest_writeq(qs, indirect->desc + (16 * i), 0);
202         /* indirect->desc[i].flags */
203         qtest_writew(qs, indirect->desc + (16 * i) + 12, VRING_DESC_F_NEXT);
204         /* indirect->desc[i].next */
205         qtest_writew(qs, indirect->desc + (16 * i) + 14, i + 1);
206     }
207 
208     return indirect;
209 }
210 
211 void qvring_indirect_desc_add(QTestState *qts, QVRingIndirectDesc *indirect,
212                               uint64_t data, uint32_t len, bool write)
213 {
214     uint16_t flags;
215 
216     g_assert_cmpint(indirect->index, <, indirect->elem);
217 
218     flags = qtest_readw(qts, indirect->desc + (16 * indirect->index) + 12);
219 
220     if (write) {
221         flags |= VRING_DESC_F_WRITE;
222     }
223 
224     /* indirect->desc[indirect->index].addr */
225     qtest_writeq(qts, indirect->desc + (16 * indirect->index), data);
226     /* indirect->desc[indirect->index].len */
227     qtest_writel(qts, indirect->desc + (16 * indirect->index) + 8, len);
228     /* indirect->desc[indirect->index].flags */
229     qtest_writew(qts, indirect->desc + (16 * indirect->index) + 12, flags);
230 
231     indirect->index++;
232 }
233 
234 uint32_t qvirtqueue_add(QTestState *qts, QVirtQueue *vq, uint64_t data,
235                         uint32_t len, bool write, bool next)
236 {
237     uint16_t flags = 0;
238     vq->num_free--;
239 
240     if (write) {
241         flags |= VRING_DESC_F_WRITE;
242     }
243 
244     if (next) {
245         flags |= VRING_DESC_F_NEXT;
246     }
247 
248     /* vq->desc[vq->free_head].addr */
249     qtest_writeq(qts, vq->desc + (16 * vq->free_head), data);
250     /* vq->desc[vq->free_head].len */
251     qtest_writel(qts, vq->desc + (16 * vq->free_head) + 8, len);
252     /* vq->desc[vq->free_head].flags */
253     qtest_writew(qts, vq->desc + (16 * vq->free_head) + 12, flags);
254 
255     return vq->free_head++; /* Return and increase, in this order */
256 }
257 
258 uint32_t qvirtqueue_add_indirect(QTestState *qts, QVirtQueue *vq,
259                                  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     qtest_writeq(qts, vq->desc + (16 * vq->free_head), indirect->desc);
269     /* vq->desc[vq->free_head].len */
270     qtest_writel(qts, vq->desc + (16 * vq->free_head) + 8,
271            sizeof(struct vring_desc) * indirect->elem);
272     /* vq->desc[vq->free_head].flags */
273     qtest_writew(qts, vq->desc + (16 * vq->free_head) + 12,
274                  VRING_DESC_F_INDIRECT);
275 
276     return vq->free_head++; /* Return and increase, in this order */
277 }
278 
279 void qvirtqueue_kick(QTestState *qts, QVirtioDevice *d, QVirtQueue *vq,
280                      uint32_t free_head)
281 {
282     /* vq->avail->idx */
283     uint16_t idx = qtest_readw(qts, vq->avail + 2);
284     /* vq->used->flags */
285     uint16_t flags;
286     /* vq->used->avail_event */
287     uint16_t avail_event;
288 
289     /* vq->avail->ring[idx % vq->size] */
290     qtest_writew(qts, vq->avail + 4 + (2 * (idx % vq->size)), free_head);
291     /* vq->avail->idx */
292     qtest_writew(qts, vq->avail + 2, idx + 1);
293 
294     /* Must read after idx is updated */
295     flags = qtest_readw(qts, vq->avail);
296     avail_event = qtest_readw(qts, vq->used + 4 +
297                                    sizeof(struct vring_used_elem) * vq->size);
298 
299     /* < 1 because we add elements to avail queue one by one */
300     if ((flags & VRING_USED_F_NO_NOTIFY) == 0 &&
301                             (!vq->event || (uint16_t)(idx-avail_event) < 1)) {
302         d->bus->virtqueue_kick(d, vq);
303     }
304 }
305 
306 /*
307  * qvirtqueue_get_buf:
308  * @desc_idx: A pointer that is filled with the vq->desc[] index, may be NULL
309  * @len: A pointer that is filled with the length written into the buffer, may
310  *       be NULL
311  *
312  * This function gets the next used element if there is one ready.
313  *
314  * Returns: true if an element was ready, false otherwise
315  */
316 bool qvirtqueue_get_buf(QTestState *qts, QVirtQueue *vq, uint32_t *desc_idx,
317                         uint32_t *len)
318 {
319     uint16_t idx;
320     uint64_t elem_addr, addr;
321 
322     idx = qtest_readw(qts, vq->used + offsetof(struct vring_used, idx));
323     if (idx == vq->last_used_idx) {
324         return false;
325     }
326 
327     elem_addr = vq->used +
328         offsetof(struct vring_used, ring) +
329         (vq->last_used_idx % vq->size) *
330         sizeof(struct vring_used_elem);
331 
332     if (desc_idx) {
333         addr = elem_addr + offsetof(struct vring_used_elem, id);
334         *desc_idx = qtest_readl(qts, addr);
335     }
336 
337     if (len) {
338         addr = elem_addr + offsetof(struct vring_used_elem, len);
339         *len = qtest_readw(qts, addr);
340     }
341 
342     vq->last_used_idx++;
343     return true;
344 }
345 
346 void qvirtqueue_set_used_event(QTestState *qts, QVirtQueue *vq, uint16_t idx)
347 {
348     g_assert(vq->event);
349 
350     /* vq->avail->used_event */
351     qtest_writew(qts, vq->avail + 4 + (2 * vq->size), idx);
352 }
353 
354 void qvirtio_start_device(QVirtioDevice *vdev)
355 {
356     qvirtio_reset(vdev);
357     qvirtio_set_acknowledge(vdev);
358     qvirtio_set_driver(vdev);
359 }
360 
361 bool qvirtio_is_big_endian(QVirtioDevice *d)
362 {
363     return d->big_endian;
364 }
365