src/patches/linux/0014-Drivers-net-hyperv-Address-UDP-checksum-issues.patch

   1 From b822ee7a17efd1bc8c7584da5d0a2c042e9ca5b6 Mon Sep 17 00:00:00 2001
   2 From: KY Srinivasan <kys@microsoft.com>
   3 Date: Wed, 9 Apr 2014 15:00:47 -0700
   4 Subject: [PATCH 14/25] Drivers: net: hyperv: Address UDP checksum issues
   5
   6 ws2008r2 does not support UDP checksum offload. Thus, we cannnot turn on
   7 UDP offload in the host. Also, on ws2012 and ws2012 r2, there appear to be
   8 an issue with UDP checksum offload.
   9 Fix this issue by computing the UDP checksum in the Hyper-V driver.
  10
  11 Based on Dave Miller's comments, in this version, I have COWed the skb
  12 before modifying the UDP header (the checksum field).
  13
  14 Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
  15 Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
  16 Signed-off-by: David S. Miller <davem@davemloft.net>
  17 ---
  18  drivers/net/hyperv/hyperv_net.h   |  1 +
  19  drivers/net/hyperv/netvsc_drv.c   | 26 +++++++++++++++++++++++++-
  20  drivers/net/hyperv/rndis_filter.c | 12 +++++++++++-
  21  3 files changed, 37 insertions(+), 2 deletions(-)
  22
  23 diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
  24 index 13010b4dae5b..d18f711d0b0c 100644
  25 --- a/drivers/net/hyperv/hyperv_net.h
  26 +++ b/drivers/net/hyperv/hyperv_net.h
  27 @@ -747,6 +747,7 @@ struct ndis_oject_header {
  28  #define NDIS_TCP_LARGE_SEND_OFFLOAD_IPV4       0
  29  #define NDIS_TCP_LARGE_SEND_OFFLOAD_IPV6       1
  30
  31 +#define VERSION_4_OFFLOAD_SIZE                 22
  32  /*
  33   * New offload OIDs for NDIS 6
  34   */
  35 diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
  36 index c76c85176644..0d898876689e 100644
  37 --- a/drivers/net/hyperv/netvsc_drv.c
  38 +++ b/drivers/net/hyperv/netvsc_drv.c
  39 @@ -399,7 +399,30 @@ static int netvsc_start_xmit(struct sk_buff *skb, struct net_device *net)
  40                 csum_info->transmit.tcp_checksum = 1;
  41                 csum_info->transmit.tcp_header_offset = hdr_offset;
  42         } else if (net_trans_info & INFO_UDP) {
  43 -               csum_info->transmit.udp_checksum = 1;
  44 +               /* UDP checksum offload is not supported on ws2008r2.
  45 +                * Furthermore, on ws2012 and ws2012r2, there are some
  46 +                * issues with udp checksum offload from Linux guests.
  47 +                * (these are host issues).
  48 +                * For now compute the checksum here.
  49 +                */
  50 +               struct udphdr *uh;
  51 +               u16 udp_len;
  52 +
  53 +               ret = skb_cow_head(skb, 0);
  54 +               if (ret)
  55 +                       goto drop;
  56 +
  57 +               uh = udp_hdr(skb);
  58 +               udp_len = ntohs(uh->len);
  59 +               uh->check = 0;
  60 +               uh->check = csum_tcpudp_magic(ip_hdr(skb)->saddr,
  61 +                                             ip_hdr(skb)->daddr,
  62 +                                             udp_len, IPPROTO_UDP,
  63 +                                             csum_partial(uh, udp_len, 0));
  64 +               if (uh->check == 0)
  65 +                       uh->check = CSUM_MANGLED_0;
  66 +
  67 +               csum_info->transmit.udp_checksum = 0;
  68         }
  69         goto do_send;
  70
  71 @@ -439,6 +462,7 @@ do_send:
  72
  73         ret = netvsc_send(net_device_ctx->device_ctx, packet);
  74
  75 +drop:
  76         if (ret == 0) {
  77                 net->stats.tx_bytes += skb_length;
  78                 net->stats.tx_packets++;
  79 diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
  80 index 4a37e3db9e32..143a98caf618 100644
  81 --- a/drivers/net/hyperv/rndis_filter.c
  82 +++ b/drivers/net/hyperv/rndis_filter.c
  83 @@ -641,6 +641,16 @@ int rndis_filter_set_offload_params(struct hv_device *hdev,
  84         struct rndis_set_complete *set_complete;
  85         u32 extlen = sizeof(struct ndis_offload_params);
  86         int ret, t;
  87 +       u32 vsp_version = nvdev->nvsp_version;
  88 +
  89 +       if (vsp_version <= NVSP_PROTOCOL_VERSION_4) {
  90 +               extlen = VERSION_4_OFFLOAD_SIZE;
  91 +               /* On NVSP_PROTOCOL_VERSION_4 and below, we do not support
  92 +                * UDP checksum offload.
  93 +                */
  94 +               req_offloads->udp_ip_v4_csum = 0;
  95 +               req_offloads->udp_ip_v6_csum = 0;
  96 +       }
  97
  98         request = get_rndis_request(rdev, RNDIS_MSG_SET,
  99                 RNDIS_MESSAGE_SIZE(struct rndis_set_request) + extlen);
 100 @@ -674,7 +684,7 @@ int rndis_filter_set_offload_params(struct hv_device *hdev,
 101         } else {
 102                 set_complete = &request->response_msg.msg.set_complete;
 103                 if (set_complete->status != RNDIS_STATUS_SUCCESS) {
 104 -                       netdev_err(ndev, "Fail to set MAC on host side:0x%x\n",
 105 +                       netdev_err(ndev, "Fail to set offload on host side:0x%x\n",
 106                                    set_complete->status);
 107                         ret = -EINVAL;
 108                 }
 109 --
 110 2.4.3
 111