diff options
| -rw-r--r-- | drivers/net/xen-netfront.c | 33 |
1 files changed, 21 insertions, 12 deletions
diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index 1db101415069..5770e3b0ba73 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -1532,40 +1532,49 @@ static int setup_netfront(struct xenbus_device *dev, struct netfront_info *info) FRONT_RING_INIT(&info->tx, txs, PAGE_SIZE); err = xenbus_grant_ring(dev, virt_to_mfn(txs)); - if (err < 0) { - free_page((unsigned long)txs); - goto fail; - } + if (err < 0) + goto grant_tx_ring_fail; info->tx_ring_ref = err; rxs = (struct xen_netif_rx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH); if (!rxs) { err = -ENOMEM; xenbus_dev_fatal(dev, err, "allocating rx ring page"); - goto fail; + goto alloc_rx_ring_fail; } SHARED_RING_INIT(rxs); FRONT_RING_INIT(&info->rx, rxs, PAGE_SIZE); err = xenbus_grant_ring(dev, virt_to_mfn(rxs)); - if (err < 0) { - free_page((unsigned long)rxs); - goto fail; - } + if (err < 0) + goto grant_rx_ring_fail; info->rx_ring_ref = err; err = xenbus_alloc_evtchn(dev, &info->evtchn); if (err) - goto fail; + goto alloc_evtchn_fail; err = bind_evtchn_to_irqhandler(info->evtchn, xennet_interrupt, 0, netdev->name, netdev); if (err < 0) - goto fail; + goto bind_fail; netdev->irq = err; return 0; - fail: + /* If we fail to setup netfront, it is safe to just revoke access to + * granted pages because backend is not accessing it at this point. + */ +bind_fail: + xenbus_free_evtchn(dev, info->evtchn); +alloc_evtchn_fail: + gnttab_end_foreign_access_ref(info->rx_ring_ref, 0); +grant_rx_ring_fail: + free_page((unsigned long)rxs); +alloc_rx_ring_fail: + gnttab_end_foreign_access_ref(info->tx_ring_ref, 0); +grant_tx_ring_fail: + free_page((unsigned long)txs); +fail: return err; } |