this could also be used for 802.1AD right?
On Tue, Jan 7, 2014 at 7:33 AM, Simon Horman <ho...@verge.net.au> wrote:
> If VLAN acceleration is used when the kernel receives a packet
> then the outer-most VLAN tag will not be present in the packet
> when it is received by netdev-linux. Rather, it will be present
> in auxdata.
>
> This patch uses recvmsg() instead of recv() to read auxdata for
> each packet and if the vlan_tid is set then it is added to the packet.
>
> Adding the vlan_tid makes use of headroom available
> in the buffer parameter of rx_recv.
>
> Signed-off-by: Simon Horman <ho...@verge.net.au>
>
> --
> v4
> * Rebase
> * Make aux variable in netdev_linux_rx_recv_sock() const
> * Use TP_STATUS_VLAN_VALID to allow vlan 0 to be read from auxdata
> * Use TP_STATUS_VLAN_TPID_VALID allow the VLAN tpid to be read
> from auxdata
>
> v3
> * Remove unnecessary cast
> * On success return 0 and increment buffer->size
> * Limit to reading one VLAN from auxdata
>
> v2
> * Updated to use eth_push_vlan() to efficiently push the VLAN
> if headroom is available. This is possible now there
> is a struct ofpbuf * to work with.
> * Various cleanups
> ---
> include/sparse/sys/socket.h | 1 +
> lib/netdev-linux.c | 152
> +++++++++++++++++++++++++++++++++++++++-----
> 2 files changed, 136 insertions(+), 17 deletions(-)
>
> diff --git a/include/sparse/sys/socket.h b/include/sparse/sys/socket.h
> index 75ee43c..3212bf4 100644
> --- a/include/sparse/sys/socket.h
> +++ b/include/sparse/sys/socket.h
> @@ -87,6 +87,7 @@ enum {
> };
>
> enum {
> + SOL_PACKET,
> SOL_SOCKET
> };
>
> diff --git a/lib/netdev-linux.c b/lib/netdev-linux.c
> index 106c18a..444369e 100644
> --- a/lib/netdev-linux.c
> +++ b/lib/netdev-linux.c
> @@ -20,11 +20,11 @@
>
> #include <errno.h>
> #include <fcntl.h>
> -#include <arpa/inet.h>
> #include <inttypes.h>
> #include <linux/filter.h>
> #include <linux/gen_stats.h>
> #include <linux/if_ether.h>
> +#include <linux/if_packet.h>
> #include <linux/if_tun.h>
> #include <linux/types.h>
> #include <linux/ethtool.h>
> @@ -37,10 +37,8 @@
> #include <sys/types.h>
> #include <sys/ioctl.h>
> #include <sys/socket.h>
> -#include <netpacket/packet.h>
> #include <net/if.h>
> #include <net/if_arp.h>
> -#include <net/if_packet.h>
> #include <net/route.h>
> #include <netinet/in.h>
> #include <poll.h>
> @@ -763,7 +761,7 @@ netdev_linux_rx_construct(struct netdev_rx *rx_)
> rx->fd = netdev->tap_fd;
> } else {
> struct sockaddr_ll sll;
> - int ifindex;
> + int ifindex, val;
> /* Result of tcpdump -dd inbound */
> static const struct sock_filter filt[] = {
> { 0x28, 0, 0, 0xfffff004 }, /* ldh [0] */
> @@ -783,6 +781,16 @@ netdev_linux_rx_construct(struct netdev_rx *rx_)
> goto error;
> }
>
> + val = 1;
> + error = setsockopt(rx->fd, SOL_PACKET, PACKET_AUXDATA,
> + &val, sizeof val);
> + if (error) {
> + error = errno;
> + VLOG_ERR("%s: failed to mark socket for auxdata (%s)",
> + netdev_get_name(netdev_), ovs_strerror(error));
> + goto error;
> + }
> +
> /* Set non-blocking mode. */
> error = set_nonblocking(rx->fd);
> if (error) {
> @@ -799,7 +807,7 @@ netdev_linux_rx_construct(struct netdev_rx *rx_)
> memset(&sll, 0, sizeof sll);
> sll.sll_family = AF_PACKET;
> sll.sll_ifindex = ifindex;
> - sll.sll_protocol = (OVS_FORCE unsigned short int)
> htons(ETH_P_ALL);
> + sll.sll_protocol = htons(ETH_P_ALL);
> if (bind(rx->fd, (struct sockaddr *) &sll, sizeof sll) < 0) {
> error = errno;
> VLOG_ERR("%s: failed to bind raw socket (%s)",
> @@ -847,31 +855,141 @@ netdev_linux_rx_dealloc(struct netdev_rx *rx_)
> free(rx);
> }
>
> +#ifdef TP_STATUS_VLAN_TPID_VALID
> +static ovs_be16
> +auxdata_to_vlan_tpid(const struct tpacket_auxdata *aux)
> +{
> + if (aux->tp_status & TP_STATUS_VLAN_TPID_VALID) {
> + return htons(aux->tp_vlan_tpid);
> + } else {
> + return htons(ETH_TYPE_VLAN);
> + }
> +}
> +#else
> +static ovs_be16
> +auxdata_to_vlan_tpid(const struct tpacket_auxdata *aux OVS_UNUSED)
> +{
> + return htons(ETH_TYPE_VLAN);
> +}
> +#endif
> +
> +/* TP_STATUS_VLAN_VALID was added to v3.0 of the linux kernel
> + * to allow VLAN 0 to be accessed via auxdata. Use it if it
> + * is available */
> +#ifdef TP_STATUS_VLAN_VALID
> +static bool
> +auxdata_has_vlan_tci(const struct tpacket_auxdata *aux)
> +{
> + return aux->tp_vlan_tci || (aux->tp_status & TP_STATUS_VLAN_VALID);
> +}
> +#else
> +static bool
> +auxdata_has_vlan_tci(const struct tpacket_auxdata *aux)
> +{
> + return aux->tp_vlan_tci;
> +}
> +#endif
> +
> static int
> -netdev_linux_rx_recv(struct netdev_rx *rx_, struct ofpbuf *buffer)
> +netdev_linux_rx_recv_sock(int fd, struct ofpbuf *buffer)
> {
> - struct netdev_rx_linux *rx = netdev_rx_linux_cast(rx_);
> + size_t size;
> ssize_t retval;
> - size_t size = ofpbuf_tailroom(buffer);
> + struct iovec iov;
> + struct cmsghdr *cmsg;
> + union {
> + struct cmsghdr cmsg;
> + char buffer[CMSG_SPACE(sizeof(struct tpacket_auxdata))];
> + } cmsg_buffer;
> + struct msghdr msgh;
> +
> + /* Reserve headroom for a single VLAN tag */
> + ofpbuf_reserve(buffer, VLAN_HEADER_LEN);
> + size = ofpbuf_tailroom(buffer);
> +
> + iov.iov_base = buffer->data;
> + iov.iov_len = size;
> + msgh.msg_name = NULL;
> + msgh.msg_namelen = 0;
> + msgh.msg_iov = &iov;
> + msgh.msg_iovlen = 1;
> + msgh.msg_control = &cmsg_buffer;
> + msgh.msg_controllen = sizeof cmsg_buffer;
> + msgh.msg_flags = 0;
>
> do {
> - retval = (rx->is_tap
> - ? read(rx->fd, buffer->data, size)
> - : recv(rx->fd, buffer->data, size, MSG_TRUNC));
> + retval = recvmsg(fd, &msgh, MSG_TRUNC);
> } while (retval < 0 && errno == EINTR);
>
> if (retval < 0) {
> - if (errno != EAGAIN) {
> - VLOG_WARN_RL(&rl, "error receiving Ethernet packet on %s: %s",
> - ovs_strerror(errno), netdev_rx_get_name(rx_));
> + return errno;
> + } else if (retval > size) {
> + return EMSGSIZE;
> + }
> +
> + buffer->size += retval;
> +
> + for (cmsg = CMSG_FIRSTHDR(&msgh); cmsg; cmsg = CMSG_NXTHDR(&msgh,
> cmsg)) {
> + const struct tpacket_auxdata *aux;
> +
> + if (cmsg->cmsg_level != SOL_PACKET
> + || cmsg->cmsg_type != PACKET_AUXDATA
> + || cmsg->cmsg_len < CMSG_LEN(sizeof(struct tpacket_auxdata)))
> {
> + continue;
> }
> +
> + aux = (struct tpacket_auxdata *)(void *)CMSG_DATA(cmsg);
> + if (auxdata_has_vlan_tci(aux)) {
> + if (retval < ETH_ADDR_LEN) {
> + return EINVAL;
> + }
> +
> + eth_push_vlan(buffer, auxdata_to_vlan_tpid(aux),
> + htons(aux->tp_vlan_tci));
> + break;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static int
> +netdev_linux_rx_recv_tap(int fd, struct ofpbuf *buffer)
> +{
> + ssize_t retval;
> + size_t size = ofpbuf_tailroom(buffer);
> +
> + do {
> + retval = read(fd, buffer->data, size);
> + } while (retval < 0 && errno == EINTR);
> +
> + if (retval < 0) {
> return errno;
> } else if (retval > size) {
> return EMSGSIZE;
> - } else {
> - buffer->size += retval;
> - return 0;
> }
> +
> + buffer->size += retval;
> + return 0;
> +}
> +
> +static int
> +netdev_linux_rx_recv(struct netdev_rx *rx_, struct ofpbuf *buffer)
> +{
> + struct netdev_rx_linux *rx = netdev_rx_linux_cast(rx_);
> + int retval;
> +
> + retval = (rx->is_tap
> + ? netdev_linux_rx_recv_tap(rx->fd, buffer)
> + : netdev_linux_rx_recv_sock(rx->fd, buffer));
> + if (retval) {
> + if (retval != EAGAIN && retval != EMSGSIZE) {
> + VLOG_WARN_RL(&rl, "error receiving Ethernet packet on %s: %s",
> + ovs_strerror(errno), netdev_rx_get_name(rx_));
> + }
> + }
> +
> + return retval;
> }
>
> static void
> --
> 1.8.4
>
> _______________________________________________
> dev mailing list
> dev@openvswitch.org
> http://openvswitch.org/mailman/listinfo/dev
>
_______________________________________________
dev mailing list
dev@openvswitch.org
http://openvswitch.org/mailman/listinfo/dev
