virtio_ccw: add support for 64 bit features.
Negotiate full 64 bit features.
Change u32 to u64, make sure to use 1ULL everywhere.
Note: devices guarantee that VERSION_1 is clear unless
revision 1 is negotiated.
Note: We don't need to re-setup the ccw, but we do it
for clarity.
Based on patches by Rusty, Thomas Huth and Cornelia.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildebrand <dahi@linux.vnet.ibm.com>
diff --git a/drivers/s390/kvm/virtio_ccw.c b/drivers/s390/kvm/virtio_ccw.c
index 244d611a..65d0c80 100644
--- a/drivers/s390/kvm/virtio_ccw.c
+++ b/drivers/s390/kvm/virtio_ccw.c
@@ -664,7 +664,8 @@
{
struct virtio_ccw_device *vcdev = to_vc_device(vdev);
struct virtio_feature_desc *features;
- int ret, rc;
+ int ret;
+ u64 rc;
struct ccw1 *ccw;
ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
@@ -677,7 +678,6 @@
goto out_free;
}
/* Read the feature bits from the host. */
- /* TODO: Features > 32 bits */
features->index = 0;
ccw->cmd_code = CCW_CMD_READ_FEAT;
ccw->flags = 0;
@@ -691,6 +691,16 @@
rc = le32_to_cpu(features->features);
+ /* Read second half of the feature bits from the host. */
+ features->index = 1;
+ ccw->cmd_code = CCW_CMD_READ_FEAT;
+ ccw->flags = 0;
+ ccw->count = sizeof(*features);
+ ccw->cda = (__u32)(unsigned long)features;
+ ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
+ if (ret == 0)
+ rc |= (u64)le32_to_cpu(features->features) << 32;
+
out_free:
kfree(features);
kfree(ccw);
@@ -714,12 +724,18 @@
/* Give virtio_ring a chance to accept features. */
vring_transport_features(vdev);
- /* Make sure we don't have any features > 32 bits! */
- BUG_ON((u32)vdev->features != vdev->features);
-
features->index = 0;
- features->features = cpu_to_le32(vdev->features);
- /* Write the feature bits to the host. */
+ features->features = cpu_to_le32((u32)vdev->features);
+ /* Write the first half of the feature bits to the host. */
+ ccw->cmd_code = CCW_CMD_WRITE_FEAT;
+ ccw->flags = 0;
+ ccw->count = sizeof(*features);
+ ccw->cda = (__u32)(unsigned long)features;
+ ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
+
+ features->index = 1;
+ features->features = cpu_to_le32(vdev->features >> 32);
+ /* Write the second half of the feature bits to the host. */
ccw->cmd_code = CCW_CMD_WRITE_FEAT;
ccw->flags = 0;
ccw->count = sizeof(*features);