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>
This commit is contained in:
Michael S. Tsirkin 2014-10-23 17:57:30 +03:00
parent cb3f6d9da4
commit c102659d69

View file

@ -160,6 +160,7 @@ static int virtio_dev_probe(struct device *_d)
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 @@ static int virtio_dev_probe(struct device *_d)
/* 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))