From e16e12be34648777606a2c03a3526409b38f0e63 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Tue, 7 Oct 2014 16:39:42 +0200 Subject: virtio: use u32, not bitmap for features It seemed like a good idea to use bitmap for features in struct virtio_device, but it's actually a pain, and seems to become even more painful when we get more than 32 feature bits. Just change it to a u32 for now. Based on patch by Rusty. Suggested-by: David Hildenbrand Signed-off-by: Rusty Russell Signed-off-by: Cornelia Huck Signed-off-by: Michael S. Tsirkin Reviewed-by: Cornelia Huck --- drivers/lguest/lguest_device.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'drivers/lguest') diff --git a/drivers/lguest/lguest_device.c b/drivers/lguest/lguest_device.c index d0a1d8a45c81..97aeb7dce5fc 100644 --- a/drivers/lguest/lguest_device.c +++ b/drivers/lguest/lguest_device.c @@ -137,14 +137,14 @@ static void lg_finalize_features(struct virtio_device *vdev) 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. + * Since lguest is currently x86-only, we're little-endian. That + * means we could just memcpy. But it's not time critical, and in + * case someone copies this code, we do it the slow, obvious way. */ memset(out_features, 0, desc->feature_len); bits = min_t(unsigned, desc->feature_len, sizeof(vdev->features)) * 8; for (i = 0; i < bits; i++) { - if (test_bit(i, vdev->features)) + if (__virtio_test_bit(vdev, i)) out_features[i / 8] |= (1 << (i % 8)); } -- cgit v1.2.3