virtio_ring: use virt_store_mb

[cascardo/linux.git] / drivers / virtio / virtio_ring.c

diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index ee663c4..e12e385 100644 (file)
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -517,10 +517,10 @@ void *virtqueue_get_buf(struct virtqueue *_vq, unsigned int *len)
        /* If we expect an interrupt for the next entry, tell host
         * by writing event index and flush out the write before
         * the read in the next get_buf call. */
-       if (!(vq->avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT)) {
-               vring_used_event(&vq->vring) = cpu_to_virtio16(_vq->vdev, vq->last_used_idx);
-               virtio_mb(vq->weak_barriers);
-       }
+       if (!(vq->avail_flags_shadow & VRING_AVAIL_F_NO_INTERRUPT))
+               virtio_store_mb(vq->weak_barriers,
+                               &vring_used_event(&vq->vring),
+                               cpu_to_virtio16(_vq->vdev, vq->last_used_idx));
 
 #ifdef DEBUG
        vq->last_add_time_valid = false;
@@ -653,8 +653,11 @@ bool virtqueue_enable_cb_delayed(struct virtqueue *_vq)
        }
        /* TODO: tune this threshold */
        bufs = (u16)(vq->avail_idx_shadow - vq->last_used_idx) * 3 / 4;
-       vring_used_event(&vq->vring) = cpu_to_virtio16(_vq->vdev, vq->last_used_idx + bufs);
-       virtio_mb(vq->weak_barriers);
+
+       virtio_store_mb(vq->weak_barriers,
+                       &vring_used_event(&vq->vring),
+                       cpu_to_virtio16(_vq->vdev, vq->last_used_idx + bufs));
+
        if (unlikely((u16)(virtio16_to_cpu(_vq->vdev, vq->vring.used->idx) - vq->last_used_idx) > bufs)) {
                END_USE(vq);
                return false;