diff options
Diffstat (limited to 'drivers/net/xen-netback/netback.c')
| -rw-r--r-- | drivers/net/xen-netback/netback.c | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 0020b2e8c279..315dfc6ea297 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -1453,7 +1453,7 @@ int xenvif_map_frontend_data_rings(struct xenvif_queue *queue, void *addr; struct xen_netif_tx_sring *txs; struct xen_netif_rx_sring *rxs; - + RING_IDX rsp_prod, req_prod; int err = -ENOMEM; err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(queue->vif), @@ -1462,7 +1462,14 @@ int xenvif_map_frontend_data_rings(struct xenvif_queue *queue, goto err; txs = (struct xen_netif_tx_sring *)addr; - BACK_RING_INIT(&queue->tx, txs, XEN_PAGE_SIZE); + rsp_prod = READ_ONCE(txs->rsp_prod); + req_prod = READ_ONCE(txs->req_prod); + + BACK_RING_ATTACH(&queue->tx, txs, rsp_prod, XEN_PAGE_SIZE); + + err = -EIO; + if (req_prod - rsp_prod > RING_SIZE(&queue->tx)) + goto err; err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(queue->vif), &rx_ring_ref, 1, &addr); @@ -1470,7 +1477,14 @@ int xenvif_map_frontend_data_rings(struct xenvif_queue *queue, goto err; rxs = (struct xen_netif_rx_sring *)addr; - BACK_RING_INIT(&queue->rx, rxs, XEN_PAGE_SIZE); + rsp_prod = READ_ONCE(rxs->rsp_prod); + req_prod = READ_ONCE(rxs->req_prod); + + BACK_RING_ATTACH(&queue->rx, rxs, rsp_prod, XEN_PAGE_SIZE); + + err = -EIO; + if (req_prod - rsp_prod > RING_SIZE(&queue->rx)) + goto err; return 0; |