KVM: s390: virtio-ccw revision 1 SET_VQ

The CCW_CMD_SET_VQ command has a different format for revision 1+
devices, allowing to specify a more complex virtqueue layout. For
now, we stay however with the old layout and simply use the new
command format for virtio-1 devices.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>

diff --git a/drivers/s390/kvm/virtio_ccw.c b/drivers/s390/kvm/virtio_ccw.c
index f6eb47b4775b6ccdd52f70421aab5a181355c780..1c21c08f33be2da7ff85da3d59c272f2a3300362 100644 (file)
--- a/drivers/s390/kvm/virtio_ccw.c
+++ b/drivers/s390/kvm/virtio_ccw.c
@@ -68,13 +68,22 @@ struct virtio_ccw_device {
        void *airq_info;
 };
 
-struct vq_info_block {
+struct vq_info_block_legacy {
        __u64 queue;
        __u32 align;
        __u16 index;
        __u16 num;
 } __packed;
 
+struct vq_info_block {
+       __u64 desc;
+       __u32 res0;
+       __u16 index;
+       __u16 num;
+       __u64 avail;
+       __u64 used;
+} __packed;
+
 struct virtio_feature_desc {
        __u32 features;
        __u8 index;
@@ -100,7 +109,10 @@ struct virtio_ccw_vq_info {
        struct virtqueue *vq;
        int num;
        void *queue;
-       struct vq_info_block *info_block;
+       union {
+               struct vq_info_block s;
+               struct vq_info_block_legacy l;
+       } *info_block;
        int bit_nr;
        struct list_head node;
        long cookie;
@@ -411,13 +423,22 @@ static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
        spin_unlock_irqrestore(&vcdev->lock, flags);
 
        /* Release from host. */
-       info->info_block->queue = 0;
-       info->info_block->align = 0;
-       info->info_block->index = index;
-       info->info_block->num = 0;
+       if (vcdev->revision == 0) {
+               info->info_block->l.queue = 0;
+               info->info_block->l.align = 0;
+               info->info_block->l.index = index;
+               info->info_block->l.num = 0;
+               ccw->count = sizeof(info->info_block->l);
+       } else {
+               info->info_block->s.desc = 0;
+               info->info_block->s.index = index;
+               info->info_block->s.num = 0;
+               info->info_block->s.avail = 0;
+               info->info_block->s.used = 0;
+               ccw->count = sizeof(info->info_block->s);
+       }
        ccw->cmd_code = CCW_CMD_SET_VQ;
        ccw->flags = 0;
-       ccw->count = sizeof(*info->info_block);
        ccw->cda = (__u32)(unsigned long)(info->info_block);
        ret = ccw_io_helper(vcdev, ccw,
                            VIRTIO_CCW_DOING_SET_VQ | index);
@@ -500,13 +521,22 @@ static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
        }
 
        /* Register it with the host. */
-       info->info_block->queue = (__u64)info->queue;
-       info->info_block->align = KVM_VIRTIO_CCW_RING_ALIGN;
-       info->info_block->index = i;
-       info->info_block->num = info->num;
+       if (vcdev->revision == 0) {
+               info->info_block->l.queue = (__u64)info->queue;
+               info->info_block->l.align = KVM_VIRTIO_CCW_RING_ALIGN;
+               info->info_block->l.index = i;
+               info->info_block->l.num = info->num;
+               ccw->count = sizeof(info->info_block->l);
+       } else {
+               info->info_block->s.desc = (__u64)info->queue;
+               info->info_block->s.index = i;
+               info->info_block->s.num = info->num;
+               info->info_block->s.avail = (__u64)virtqueue_get_avail(vq);
+               info->info_block->s.used = (__u64)virtqueue_get_used(vq);
+               ccw->count = sizeof(info->info_block->s);
+       }
        ccw->cmd_code = CCW_CMD_SET_VQ;
        ccw->flags = 0;
-       ccw->count = sizeof(*info->info_block);
        ccw->cda = (__u32)(unsigned long)(info->info_block);
        err = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_VQ | i);
        if (err) {