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authorSridhar Samudrala <sri@us.ibm.com>2010-02-04 20:24:10 -0800
committerDavid S. Miller <davem@davemloft.net>2010-02-04 20:24:10 -0800
commitbfd5f4a3d605e0f6054df0b59fe0907ff7e696d3 (patch)
tree63d19326b491b507f246ea4c3ef410d62602e794
parent746079dabcf74be2a16dc983ac597156e3d2e051 (diff)
packet: Add GSO/csum offload support.
This patch adds GSO/checksum offload to af_packet sockets using virtio_net_hdr. Based on Rusty's patch to add this support to tun. It allows GSO/checksum offload to be enabled when using raw socket backend with virtio_net. Adds PACKET_VNET_HDR socket option to prepend virtio_net_hdr in the receive path and process/skip virtio_net_hdr in the send path. This option is only allowed with SOCK_RAW sockets attached to ethernet type devices. v2 updates ---------- Michael's Comments - Perform length check in packet_snd() when GSO is off even when vnet_hdr is present. - Check for SKB_GSO_FCOE type and return -EINVAL - don't allow tx/rx ring when vnet_hdr is enabled. Herbert's Comments - Removed ethernet specific code. - protocol value is assumed to be passed in by the caller. Signed-off-by: Sridhar Samudrala <sri@us.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--include/linux/if_packet.h1
-rw-r--r--net/packet/af_packet.c187
2 files changed, 177 insertions, 11 deletions
diff --git a/include/linux/if_packet.h b/include/linux/if_packet.h
index 4021d47cc43..aa57a5f993f 100644
--- a/include/linux/if_packet.h
+++ b/include/linux/if_packet.h
@@ -46,6 +46,7 @@ struct sockaddr_ll {
#define PACKET_RESERVE 12
#define PACKET_TX_RING 13
#define PACKET_LOSS 14
+#define PACKET_VNET_HDR 15
struct tpacket_stats {
unsigned int tp_packets;
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 53633c5fdb1..178e2937bba 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -80,6 +80,7 @@
#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/if_vlan.h>
+#include <linux/virtio_net.h>
#ifdef CONFIG_INET
#include <net/inet_common.h>
@@ -193,7 +194,8 @@ struct packet_sock {
struct mutex pg_vec_lock;
unsigned int running:1, /* prot_hook is attached*/
auxdata:1,
- origdev:1;
+ origdev:1,
+ has_vnet_hdr:1;
int ifindex; /* bound device */
__be16 num;
struct packet_mclist *mclist;
@@ -1056,6 +1058,30 @@ out:
}
#endif
+static inline struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
+ size_t reserve, size_t len,
+ size_t linear, int noblock,
+ int *err)
+{
+ struct sk_buff *skb;
+
+ /* Under a page? Don't bother with paged skb. */
+ if (prepad + len < PAGE_SIZE || !linear)
+ linear = len;
+
+ skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
+ err);
+ if (!skb)
+ return NULL;
+
+ skb_reserve(skb, reserve);
+ skb_put(skb, linear);
+ skb->data_len = len - linear;
+ skb->len += len - linear;
+
+ return skb;
+}
+
static int packet_snd(struct socket *sock,
struct msghdr *msg, size_t len)
{
@@ -1066,14 +1092,17 @@ static int packet_snd(struct socket *sock,
__be16 proto;
unsigned char *addr;
int ifindex, err, reserve = 0;
+ struct virtio_net_hdr vnet_hdr = { 0 };
+ int offset = 0;
+ int vnet_hdr_len;
+ struct packet_sock *po = pkt_sk(sk);
+ unsigned short gso_type = 0;
/*
* Get and verify the address.
*/
if (saddr == NULL) {
- struct packet_sock *po = pkt_sk(sk);
-
ifindex = po->ifindex;
proto = po->num;
addr = NULL;
@@ -1100,25 +1129,74 @@ static int packet_snd(struct socket *sock,
if (!(dev->flags & IFF_UP))
goto out_unlock;
+ if (po->has_vnet_hdr) {
+ vnet_hdr_len = sizeof(vnet_hdr);
+
+ err = -EINVAL;
+ if (len < vnet_hdr_len)
+ goto out_unlock;
+
+ len -= vnet_hdr_len;
+
+ err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov,
+ vnet_hdr_len);
+ if (err < 0)
+ goto out_unlock;
+
+ if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
+ (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
+ vnet_hdr.hdr_len))
+ vnet_hdr.hdr_len = vnet_hdr.csum_start +
+ vnet_hdr.csum_offset + 2;
+
+ err = -EINVAL;
+ if (vnet_hdr.hdr_len > len)
+ goto out_unlock;
+
+ if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
+ switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
+ case VIRTIO_NET_HDR_GSO_TCPV4:
+ gso_type = SKB_GSO_TCPV4;
+ break;
+ case VIRTIO_NET_HDR_GSO_TCPV6:
+ gso_type = SKB_GSO_TCPV6;
+ break;
+ case VIRTIO_NET_HDR_GSO_UDP:
+ gso_type = SKB_GSO_UDP;
+ break;
+ default:
+ goto out_unlock;
+ }
+
+ if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
+ gso_type |= SKB_GSO_TCP_ECN;
+
+ if (vnet_hdr.gso_size == 0)
+ goto out_unlock;
+
+ }
+ }
+
err = -EMSGSIZE;
- if (len > dev->mtu+reserve)
+ if (!gso_type && (len > dev->mtu+reserve))
goto out_unlock;
- skb = sock_alloc_send_skb(sk, len + LL_ALLOCATED_SPACE(dev),
- msg->msg_flags & MSG_DONTWAIT, &err);
+ err = -ENOBUFS;
+ skb = packet_alloc_skb(sk, LL_ALLOCATED_SPACE(dev),
+ LL_RESERVED_SPACE(dev), len, vnet_hdr.hdr_len,
+ msg->msg_flags & MSG_DONTWAIT, &err);
if (skb == NULL)
goto out_unlock;
- skb_reserve(skb, LL_RESERVED_SPACE(dev));
- skb_reset_network_header(skb);
+ skb_set_network_header(skb, reserve);
err = -EINVAL;
if (sock->type == SOCK_DGRAM &&
- dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len) < 0)
+ (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
goto out_free;
/* Returns -EFAULT on error */
- err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
+ err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
if (err)
goto out_free;
@@ -1127,6 +1205,25 @@ static int packet_snd(struct socket *sock,
skb->priority = sk->sk_priority;
skb->mark = sk->sk_mark;
+ if (po->has_vnet_hdr) {
+ if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
+ if (!skb_partial_csum_set(skb, vnet_hdr.csum_start,
+ vnet_hdr.csum_offset)) {
+ err = -EINVAL;
+ goto out_free;
+ }
+ }
+
+ skb_shinfo(skb)->gso_size = vnet_hdr.gso_size;
+ skb_shinfo(skb)->gso_type = gso_type;
+
+ /* Header must be checked, and gso_segs computed. */
+ skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
+ skb_shinfo(skb)->gso_segs = 0;
+
+ len += vnet_hdr_len;
+ }
+
/*
* Now send it
*/
@@ -1420,6 +1517,7 @@ static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
struct sk_buff *skb;
int copied, err;
struct sockaddr_ll *sll;
+ int vnet_hdr_len = 0;
err = -EINVAL;
if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT))
@@ -1451,6 +1549,48 @@ static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
if (skb == NULL)
goto out;
+ if (pkt_sk(sk)->has_vnet_hdr) {
+ struct virtio_net_hdr vnet_hdr = { 0 };
+
+ err = -EINVAL;
+ vnet_hdr_len = sizeof(vnet_hdr);
+ if ((len -= vnet_hdr_len) < 0)
+ goto out_free;
+
+ if (skb_is_gso(skb)) {
+ struct skb_shared_info *sinfo = skb_shinfo(skb);
+
+ /* This is a hint as to how much should be linear. */
+ vnet_hdr.hdr_len = skb_headlen(skb);
+ vnet_hdr.gso_size = sinfo->gso_size;
+ if (sinfo->gso_type & SKB_GSO_TCPV4)
+ vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
+ else if (sinfo->gso_type & SKB_GSO_TCPV6)
+ vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
+ else if (sinfo->gso_type & SKB_GSO_UDP)
+ vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
+ else if (sinfo->gso_type & SKB_GSO_FCOE)
+ goto out_free;
+ else
+ BUG();
+ if (sinfo->gso_type & SKB_GSO_TCP_ECN)
+ vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
+ } else
+ vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
+
+ if (skb->ip_summed == CHECKSUM_PARTIAL) {
+ vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
+ vnet_hdr.csum_start = skb->csum_start -
+ skb_headroom(skb);
+ vnet_hdr.csum_offset = skb->csum_offset;
+ } /* else everything is zero */
+
+ err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
+ vnet_hdr_len);
+ if (err < 0)
+ goto out_free;
+ }
+
/*
* If the address length field is there to be filled in, we fill
* it in now.
@@ -1502,7 +1642,7 @@ static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
* Free or return the buffer as appropriate. Again this
* hides all the races and re-entrancy issues from us.
*/
- err = (flags&MSG_TRUNC) ? skb->len : copied;
+ err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
out_free:
skb_free_datagram(sk, skb);
@@ -1740,6 +1880,8 @@ packet_setsockopt(struct socket *sock, int level, int optname, char __user *optv
if (optlen < sizeof(req))
return -EINVAL;
+ if (pkt_sk(sk)->has_vnet_hdr)
+ return -EINVAL;
if (copy_from_user(&req, optval, sizeof(req)))
return -EFAULT;
return packet_set_ring(sk, &req, 0, optname == PACKET_TX_RING);
@@ -1826,6 +1968,22 @@ packet_setsockopt(struct socket *sock, int level, int optname, char __user *optv
po->origdev = !!val;
return 0;
}
+ case PACKET_VNET_HDR:
+ {
+ int val;
+
+ if (sock->type != SOCK_RAW)
+ return -EINVAL;
+ if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
+ return -EBUSY;
+ if (optlen < sizeof(val))
+ return -EINVAL;
+ if (copy_from_user(&val, optval, sizeof(val)))
+ return -EFAULT;
+
+ po->has_vnet_hdr = !!val;
+ return 0;
+ }
default:
return -ENOPROTOOPT;
}
@@ -1876,6 +2034,13 @@ static int packet_getsockopt(struct socket *sock, int level, int optname,
data = &val;
break;
+ case PACKET_VNET_HDR:
+ if (len > sizeof(int))
+ len = sizeof(int);
+ val = po->has_vnet_hdr;
+
+ data = &val;
+ break;
#ifdef CONFIG_PACKET_MMAP
case PACKET_VERSION:
if (len > sizeof(int))