[PATCH v2 05/12] dm: test: virtio: Test the virtio ring

[Andrew Scull]

The virtio ring is the basis of virtio communication. Test its basic
functionality and its resilience against corruption from the device.

Signed-off-by: Andrew Scull <asc...@google.com>
Reviewed-by: Simon Glass <s...@chromium.org>
---
 test/dm/virtio.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 72 insertions(+)

diff --git a/test/dm/virtio.c b/test/dm/virtio.c
index 9a7e658cce..adef10592c 100644
--- a/test/dm/virtio.c
+++ b/test/dm/virtio.c
@@ -130,3 +130,75 @@ static int dm_test_virtio_remove(struct unit_test_state 
*uts)
        return 0;
 }
 DM_TEST(dm_test_virtio_remove, UT_TESTF_SCAN_PDATA | UT_TESTF_SCAN_FDT);
+
+/* Test all of the virtio ring */
+static int dm_test_virtio_ring(struct unit_test_state *uts)
+{
+       struct udevice *bus, *dev;
+       struct virtio_dev_priv *uc_priv;
+       struct virtqueue *vq;
+       struct virtio_sg sg[2];
+       struct virtio_sg *sgs[2];
+       unsigned int len;
+       u8 buffer[2][32];
+
+       /* check probe success */
+       ut_assertok(uclass_first_device(UCLASS_VIRTIO, &bus));
+       ut_assertnonnull(bus);
+
+       /* check the child virtio-blk device is bound */
+       ut_assertok(device_find_first_child(bus, &dev));
+       ut_assertnonnull(dev);
+
+       /*
+        * fake the virtio device probe by filling in uc_priv->vdev
+        * which is used by virtio_find_vqs/virtio_del_vqs.
+        */
+       uc_priv = dev_get_uclass_priv(bus);
+       ut_assertnonnull(uc_priv);
+       uc_priv->vdev = dev;
+
+       /* prepare the scatter-gather buffer */
+       sg[0].addr = buffer[0];
+       sg[0].length = sizeof(buffer[0]);
+       sg[1].addr = buffer[1];
+       sg[1].length = sizeof(buffer[1]);
+       sgs[0] = &sg[0];
+       sgs[1] = &sg[1];
+
+       /* read a buffer and report written size from device */
+       ut_assertok(virtio_find_vqs(dev, 1, &vq));
+       ut_assertok(virtqueue_add(vq, sgs, 0, 1));
+       vq->vring.used->idx = 1;
+       vq->vring.used->ring[0].id = 0;
+       vq->vring.used->ring[0].len = 0x53355885;
+       ut_asserteq_ptr(buffer, virtqueue_get_buf(vq, &len));
+       ut_asserteq(0x53355885, len);
+       ut_assertok(virtio_del_vqs(dev));
+
+       /* rejects used descriptors that aren't a chain head */
+       ut_assertok(virtio_find_vqs(dev, 1, &vq));
+       ut_assertok(virtqueue_add(vq, sgs, 0, 2));
+       vq->vring.used->idx = 1;
+       vq->vring.used->ring[0].id = 1;
+       vq->vring.used->ring[0].len = 0x53355885;
+       ut_assertnull(virtqueue_get_buf(vq, &len));
+       ut_assertok(virtio_del_vqs(dev));
+
+       /* device changes to descriptor are ignored */
+       ut_assertok(virtio_find_vqs(dev, 1, &vq));
+       ut_assertok(virtqueue_add(vq, sgs, 0, 1));
+       vq->vring.desc[0].addr = cpu_to_virtio64(dev, 0xbadbad11);
+       vq->vring.desc[0].len = cpu_to_virtio32(dev, 0x11badbad);
+       vq->vring.desc[0].flags = cpu_to_virtio16(dev, VRING_DESC_F_NEXT);
+       vq->vring.desc[0].next = cpu_to_virtio16(dev, U16_MAX);
+       vq->vring.used->idx = 1;
+       vq->vring.used->ring[0].id = 0;
+       vq->vring.used->ring[0].len = 6;
+       ut_asserteq_ptr(buffer, virtqueue_get_buf(vq, &len));
+       ut_asserteq(6, len);
+       ut_assertok(virtio_del_vqs(dev));
+
+       return 0;
+}
+DM_TEST(dm_test_virtio_ring, UT_TESTF_SCAN_PDATA | UT_TESTF_SCAN_FDT);
-- 
2.35.1.1178.g4f1659d476-goog