[PATCH v5 17/45] KVM: s390: virtio-ccw revision 1 SET_VQ

Michael S. Tsirkin
2014-11-27T12:31:30Z

From: Cornelia Huck <cornelia.huck@de.ibm.com>

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>
---
drivers/s390/kvm/virtio_ccw.c | 54 +++++++++++++++++++++++++++++++++----------
1 file changed, 42 insertions(+), 12 deletions(-)

diff --git a/drivers/s390/kvm/virtio_ccw.c b/drivers/s390/kvm/virtio_ccw.c
index 193e8f1..ad06e11 100644
--- 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) {
--
MST