[RFC PATCH 22/24] vdpa_sim: factor out buffer completion logic

From: Jason Wang
Date: Wed Sep 23 2020 - 23:26:08 EST


This patch factors out the buffer completion logic in order to support
future features.

Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
---
drivers/vdpa/vdpa_sim/vdpa_sim.c | 33 +++++++++++++++++---------------
1 file changed, 18 insertions(+), 15 deletions(-)

diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
index ca5c2d0db905..b21670e054ba 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
@@ -155,6 +155,22 @@ static void vdpasim_reset(struct vdpasim *vdpasim)
++vdpasim->generation;
}

+static void vdpasim_complete(struct vdpasim_virtqueue *vq, size_t len)
+{
+ /* Make sure data is wrote before advancing index */
+ smp_wmb();
+
+ vringh_complete_iotlb(&vq->vring, vq->head, len);
+
+ /* Make sure used is visible before rasing the interrupt. */
+ smp_wmb();
+
+ local_bh_disable();
+ if (vq->cb)
+ vq->cb(vq->private);
+ local_bh_enable();
+}
+
static void vdpasim_work(struct work_struct *work)
{
struct vdpasim *vdpasim = container_of(work, struct
@@ -203,21 +219,8 @@ static void vdpasim_work(struct work_struct *work)
total_write += write;
}

- /* Make sure data is wrote before advancing index */
- smp_wmb();
-
- vringh_complete_iotlb(&txq->vring, txq->head, 0);
- vringh_complete_iotlb(&rxq->vring, rxq->head, total_write);
-
- /* Make sure used is visible before rasing the interrupt. */
- smp_wmb();
-
- local_bh_disable();
- if (txq->cb)
- txq->cb(txq->private);
- if (rxq->cb)
- rxq->cb(rxq->private);
- local_bh_enable();
+ vdpasim_complete(txq, 0);
+ vdpasim_complete(rxq, total_write);

if (++pkts > 4) {
schedule_work(&vdpasim->work);
--
2.20.1