This is the basic sceleton which will be fleshed out by individiual
extensions.
Signed-off-by: Vladislav Yasevich <vyase...@redhat.com>
---
drivers/net/virtio_net.c | 21 +++++++++++++++++++++
include/linux/virtio_net.h | 12 ++++++++++++
include/uapi/linux/virtio_net.h | 11 +++++++++++
3 files changed, 44 insertions(+)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 2905d52..b61de96 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -132,6 +132,10 @@ struct virtnet_info {
/* Packet virtio header size */
u8 hdr_len;
+ /* Header extensions were negotiated */
+ bool hdr_ext;
+ u32 ext_mask;
+
/* Active statistics */
struct virtnet_stats __percpu *stats;
@@ -161,6 +165,11 @@ struct virtnet_info {
u32 speed;
};
+struct virtio_net_hdr_max {
+ struct virtio_net_hdr_mrg_rxbuf hdr;
+ struct virtio_net_ext_hdr ext_hdr;
+};
+
static inline u8 padded_vnet_hdr(struct virtnet_info *vi)
{
u8 hdr_len = vi->hdr_len;
@@ -201,6 +210,7 @@ static int rxq2vq(int rxq)
static inline struct virtio_net_hdr_mrg_rxbuf *skb_vnet_hdr(struct sk_buff
*skb)
{
+ BUILD_BUG_ON(sizeof(struct virtio_net_hdr_max) > sizeof(skb->cb));
return (struct virtio_net_hdr_mrg_rxbuf *)skb->cb;
}
@@ -759,6 +769,12 @@ static void receive_buf(struct virtnet_info *vi, struct
receive_queue *rq,
goto frame_err;
}
+ if (vi->hdr_ext &&
+ virtio_net_ext_to_skb(skb,
+ (struct virtio_net_ext_hdr *)(hdr + 1))) {
+ goto frame_err;
+ }
+
skb->protocol = eth_type_trans(skb, dev);
pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
ntohs(skb->protocol), skb->len, skb->pkt_type);
@@ -1114,6 +1130,11 @@ static int xmit_skb(struct send_queue *sq, struct
sk_buff *skb)
if (vi->mergeable_rx_bufs)
hdr->num_buffers = 0;
+ if (vi->hdr_ext &&
+ virtio_net_ext_from_skb(skb, (struct virtio_net_ext_hdr *)(hdr + 1),
+ vi->ext_mask))
+ BUG();
+
sg_init_table(sq->sg, skb_shinfo(skb)->nr_frags + (can_push ? 1 : 2));
if (can_push) {
__skb_push(skb, hdr_len);
diff --git a/include/linux/virtio_net.h b/include/linux/virtio_net.h
index 5643647..4790ade 100644
--- a/include/linux/virtio_net.h
+++ b/include/linux/virtio_net.h
@@ -96,4 +96,16 @@ static inline int virtio_net_hdr_from_skb(const struct
sk_buff *skb,
return 0;
}
+static inline int virtio_net_ext_to_skb(struct sk_buff *skb,
+ struct virtio_net_ext_hdr *ext)
+{
+ return 0;
+}
+
+static inline int virtio_net_ext_from_skb(const struct sk_buff *skb,
+ struct virtio_net_ext_hdr *ext,
+ __u32 ext_mask)
+{
+ return 0;
+}
#endif /* _LINUX_VIRTIO_NET_H */
diff --git a/include/uapi/linux/virtio_net.h b/include/uapi/linux/virtio_net.h
index fc353b5..0039b72 100644
--- a/include/uapi/linux/virtio_net.h
+++ b/include/uapi/linux/virtio_net.h
@@ -88,6 +88,7 @@ struct virtio_net_config {
struct virtio_net_hdr_v1 {
#define VIRTIO_NET_HDR_F_NEEDS_CSUM 1 /* Use csum_start, csum_offset
*/
#define VIRTIO_NET_HDR_F_DATA_VALID 2 /* Csum is valid */
+#define VIRTIO_NET_HDR_F_VNET_EXT 4 /* Vnet extensions present */
__u8 flags;
#define VIRTIO_NET_HDR_GSO_NONE 0 /* Not a GSO frame */
#define VIRTIO_NET_HDR_GSO_TCPV4 1 /* GSO frame, IPv4 TCP (TSO) */
@@ -102,6 +103,16 @@ struct virtio_net_hdr_v1 {
__virtio16 num_buffers; /* Number of merged rx buffers */
};
+/* If IRTIO_NET_HDR_F_VNET_EXT flags is set, this header immediately
+ * follows the virtio_net_hdr. The flags in this header will indicate
+ * which extension will follow. The extnsion data will immidiately follow
+ * this header.
+ */
+struct virtio_net_ext_hdr {
+ __u32 flags;
+ __u8 extensions[];
+};
+
#ifndef VIRTIO_NET_NO_LEGACY
/* This header comes first in the scatter-gather list.
* For legacy virtio, if VIRTIO_F_ANY_LAYOUT is not negotiated, it must
--
2.7.4
