virtio: simplify feature bit handling
Now that we use u64 for bits, we can simply & them together.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index 9248125..3e78f4b 100644
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -160,6 +160,7 @@
struct virtio_device *dev = dev_to_virtio(_d);
struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
u64 device_features;
+ u64 driver_features;
unsigned status;
/* We have a driver! */
@@ -168,15 +169,16 @@
/* Figure out what features the device supports. */
device_features = dev->config->get_features(dev);
- /* Features supported by both device and driver into dev->features. */
- dev->features = 0;
+ /* Figure out what features the driver supports. */
+ driver_features = 0;
for (i = 0; i < drv->feature_table_size; i++) {
unsigned int f = drv->feature_table[i];
BUG_ON(f >= 64);
- if (device_features & (1ULL << f))
- __virtio_set_bit(dev, f);
+ driver_features |= (1ULL << f);
}
+ dev->features = driver_features & device_features;
+
/* Transport features always preserved to pass to finalize_features. */
for (i = VIRTIO_TRANSPORT_F_START; i < VIRTIO_TRANSPORT_F_END; i++)
if (device_features & (1ULL << i))