[PATCH v4 14/18] vdpa_sim: set vringh notify callback

[Stefano Garzarella]

Instead of calling the vq callback directly, we can leverage the
vringh_notify() function, adding vdpasim_vq_notify() and setting it
in the vringh notify callback.

Suggested-by: Jason Wang <jasow...@redhat.com>
Acked-by: Jason Wang <jasow...@redhat.com>
Signed-off-by: Stefano Garzarella <sgarz...@redhat.com>
---
v3:
- cleared notify during reset [Jason]
---
 drivers/vdpa/vdpa_sim/vdpa_sim.c | 23 +++++++++++++++++++----
 1 file changed, 19 insertions(+), 4 deletions(-)

diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
index e219aa852ef8..19ff5e352782 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
@@ -131,6 +131,17 @@ static struct vdpasim *dev_to_sim(struct device *dev)
        return vdpa_to_sim(vdpa);
 }
 
+static void vdpasim_vq_notify(struct vringh *vring)
+{
+       struct vdpasim_virtqueue *vq =
+               container_of(vring, struct vdpasim_virtqueue, vring);
+
+       if (!vq->cb)
+               return;
+
+       vq->cb(vq->private);
+}
+
 static void vdpasim_queue_ready(struct vdpasim *vdpasim, unsigned int idx)
 {
        struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx];
@@ -142,6 +153,8 @@ static void vdpasim_queue_ready(struct vdpasim *vdpasim, 
unsigned int idx)
                          (uintptr_t)vq->driver_addr,
                          (struct vring_used *)
                          (uintptr_t)vq->device_addr);
+
+       vq->vring.notify = vdpasim_vq_notify;
 }
 
 static void vdpasim_vq_reset(struct vdpasim *vdpasim,
@@ -155,6 +168,8 @@ static void vdpasim_vq_reset(struct vdpasim *vdpasim,
        vq->private = NULL;
        vringh_init_iotlb(&vq->vring, vdpasim->dev_attr.supported_features,
                          VDPASIM_QUEUE_MAX, false, NULL, NULL, NULL);
+
+       vq->vring.notify = NULL;
 }
 
 static void vdpasim_reset(struct vdpasim *vdpasim)
@@ -231,10 +246,10 @@ static void vdpasim_net_work(struct work_struct *work)
                smp_wmb();
 
                local_bh_disable();
-               if (txq->cb)
-                       txq->cb(txq->private);
-               if (rxq->cb)
-                       rxq->cb(rxq->private);
+               if (vringh_need_notify_iotlb(&txq->vring) > 0)
+                       vringh_notify(&txq->vring);
+               if (vringh_need_notify_iotlb(&rxq->vring) > 0)
+                       vringh_notify(&rxq->vring);
                local_bh_enable();
 
                if (++pkts > 4) {
-- 
2.26.2