From af807c82978ec1b8c5120b59b78ef951b3e4603b Mon Sep 17 00:00:00 2001 From: Dave Graham Date: Thu, 9 Oct 2008 14:28:58 -0700 Subject: [PATCH] e1000e: don't generate bad checksums for tcp packets with 0 csum When offloading transmit checksums only, the driver was not correctly configuring the hardware to handle the case of a zero checksum. For UDP the correct behavior is to leave it alone, but for tcp the checksum must be changed from 0x0000 to 0xFFFF. The hardware takes care of this case but only if it is told the packet is tcp. Signed-off-by: Dave Graham Signed-off-by: Jesse Brandeburg Signed-off-by: Jeff Kirsher Signed-off-by: David S. Miller --- drivers/net/e1000e/netdev.c | 64 +++++++++++++++++++++++-------------- 1 file changed, 40 insertions(+), 24 deletions(-) diff --git a/drivers/net/e1000e/netdev.c b/drivers/net/e1000e/netdev.c index 1b72749979c4..abd492b7336d 100644 --- a/drivers/net/e1000e/netdev.c +++ b/drivers/net/e1000e/netdev.c @@ -3749,34 +3749,50 @@ static bool e1000_tx_csum(struct e1000_adapter *adapter, struct sk_buff *skb) struct e1000_buffer *buffer_info; unsigned int i; u8 css; + u32 cmd_len = E1000_TXD_CMD_DEXT; - if (skb->ip_summed == CHECKSUM_PARTIAL) { - css = skb_transport_offset(skb); + if (skb->ip_summed != CHECKSUM_PARTIAL) + return 0; - i = tx_ring->next_to_use; - buffer_info = &tx_ring->buffer_info[i]; - context_desc = E1000_CONTEXT_DESC(*tx_ring, i); - - context_desc->lower_setup.ip_config = 0; - context_desc->upper_setup.tcp_fields.tucss = css; - context_desc->upper_setup.tcp_fields.tucso = - css + skb->csum_offset; - context_desc->upper_setup.tcp_fields.tucse = 0; - context_desc->tcp_seg_setup.data = 0; - context_desc->cmd_and_length = cpu_to_le32(E1000_TXD_CMD_DEXT); - - buffer_info->time_stamp = jiffies; - buffer_info->next_to_watch = i; - - i++; - if (i == tx_ring->count) - i = 0; - tx_ring->next_to_use = i; - - return 1; + switch (skb->protocol) { + case __constant_htons(ETH_P_IP): + if (ip_hdr(skb)->protocol == IPPROTO_TCP) + cmd_len |= E1000_TXD_CMD_TCP; + break; + case __constant_htons(ETH_P_IPV6): + /* XXX not handling all IPV6 headers */ + if (ipv6_hdr(skb)->nexthdr == IPPROTO_TCP) + cmd_len |= E1000_TXD_CMD_TCP; + break; + default: + if (unlikely(net_ratelimit())) + e_warn("checksum_partial proto=%x!\n", skb->protocol); + break; } - return 0; + css = skb_transport_offset(skb); + + i = tx_ring->next_to_use; + buffer_info = &tx_ring->buffer_info[i]; + context_desc = E1000_CONTEXT_DESC(*tx_ring, i); + + context_desc->lower_setup.ip_config = 0; + context_desc->upper_setup.tcp_fields.tucss = css; + context_desc->upper_setup.tcp_fields.tucso = + css + skb->csum_offset; + context_desc->upper_setup.tcp_fields.tucse = 0; + context_desc->tcp_seg_setup.data = 0; + context_desc->cmd_and_length = cpu_to_le32(cmd_len); + + buffer_info->time_stamp = jiffies; + buffer_info->next_to_watch = i; + + i++; + if (i == tx_ring->count) + i = 0; + tx_ring->next_to_use = i; + + return 1; } #define E1000_MAX_PER_TXD 8192