diff options
| -rw-r--r-- | drivers/net/xen-netback/common.h | 19 | ||||
| -rw-r--r-- | drivers/net/xen-netback/interface.c | 10 | ||||
| -rw-r--r-- | drivers/net/xen-netback/netback.c | 2 |
3 files changed, 24 insertions, 7 deletions
diff --git a/drivers/net/xen-netback/common.h b/drivers/net/xen-netback/common.h index 08ae01b41c83..c47794b9d42f 100644 --- a/drivers/net/xen-netback/common.h +++ b/drivers/net/xen-netback/common.h @@ -101,6 +101,13 @@ struct xenvif_rx_meta { #define MAX_PENDING_REQS 256 +/* It's possible for an skb to have a maximal number of frags + * but still be less than MAX_BUFFER_OFFSET in size. Thus the + * worst-case number of copy operations is MAX_SKB_FRAGS per + * ring slot. + */ +#define MAX_GRANT_COPY_OPS (MAX_SKB_FRAGS * XEN_NETIF_RX_RING_SIZE) + struct xenvif { /* Unique identifier for this interface. */ domid_t domid; @@ -143,13 +150,13 @@ struct xenvif { */ RING_IDX rx_req_cons_peek; - /* Given MAX_BUFFER_OFFSET of 4096 the worst case is that each - * head/fragment page uses 2 copy operations because it - * straddles two buffers in the frontend. - */ - struct gnttab_copy grant_copy_op[2*XEN_NETIF_RX_RING_SIZE]; - struct xenvif_rx_meta meta[2*XEN_NETIF_RX_RING_SIZE]; + /* This array is allocated seperately as it is large */ + struct gnttab_copy *grant_copy_op; + /* We create one meta structure per ring request we consume, so + * the maximum number is the same as the ring size. + */ + struct xenvif_rx_meta meta[XEN_NETIF_RX_RING_SIZE]; u8 fe_dev_addr[6]; diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index 870f1fa58370..34ca4e58a43d 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -307,6 +307,15 @@ struct xenvif *xenvif_alloc(struct device *parent, domid_t domid, SET_NETDEV_DEV(dev, parent); vif = netdev_priv(dev); + + vif->grant_copy_op = vmalloc(sizeof(struct gnttab_copy) * + MAX_GRANT_COPY_OPS); + if (vif->grant_copy_op == NULL) { + pr_warn("Could not allocate grant copy space for %s\n", name); + free_netdev(dev); + return ERR_PTR(-ENOMEM); + } + vif->domid = domid; vif->handle = handle; vif->can_sg = 1; @@ -487,6 +496,7 @@ void xenvif_free(struct xenvif *vif) unregister_netdev(vif->dev); + vfree(vif->grant_copy_op); free_netdev(vif->dev); module_put(THIS_MODULE); diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 7b4fd93be76d..78425554a537 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -608,7 +608,7 @@ void xenvif_rx_action(struct xenvif *vif) if (!npo.copy_prod) return; - BUG_ON(npo.copy_prod > ARRAY_SIZE(vif->grant_copy_op)); + BUG_ON(npo.copy_prod > MAX_GRANT_COPY_OPS); gnttab_batch_copy(vif->grant_copy_op, npo.copy_prod); while ((skb = __skb_dequeue(&rxq)) != NULL) { |