return features;
}
-static void lg_set_features(struct virtio_device *vdev, u32 features)
+/* The virtio core takes the features the Host offers, and copies the
+ * ones supported by the driver into the vdev->features array. Once
+ * that's all sorted out, this routine is called so we can tell the
+ * Host which features we understand and accept. */
+static void lg_finalize_features(struct virtio_device *vdev)
{
- unsigned int i;
+ unsigned int i, bits;
struct lguest_device_desc *desc = to_lgdev(vdev)->desc;
/* Second half of bitmap is features we accept. */
u8 *out_features = lg_features(desc) + desc->feature_len;
+ /* Give virtio_ring a chance to accept features. */
+ vring_transport_features(vdev);
+
+ /* The vdev->feature array is a Linux bitmask: this isn't the
+ * same as a the simple array of bits used by lguest devices
+ * for features. So we do this slow, manual conversion which is
+ * completely general. */
memset(out_features, 0, desc->feature_len);
- for (i = 0; i < min(desc->feature_len * 8, 32); i++) {
- if (features & (1 << i))
+ bits = min_t(unsigned, desc->feature_len, sizeof(vdev->features)) * 8;
+ for (i = 0; i < bits; i++) {
+ if (test_bit(i, vdev->features))
out_features[i / 8] |= (1 << (i % 8));
}
}
/* The ops structure which hooks everything together. */
static struct virtio_config_ops lguest_config_ops = {
.get_features = lg_get_features,
- .set_features = lg_set_features,
+ .finalize_features = lg_finalize_features,
.get = lg_get,
.set = lg_set,
.get_status = lg_get_status,