From 12b0004d1d1e2a9aa667412d479041e403bcafae Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Tue, 5 Feb 2013 16:36:38 +0000 Subject: [PATCH] net: adjust skb_gso_segment() for calling in rx path skb_gso_segment() is almost always called in tx path, except for openvswitch. It calls this function when it receives the packet and tries to queue it to user-space. In this special case, the ->ip_summed check inside skb_gso_segment() is no longer true, as ->ip_summed value has different meanings on rx path. This patch adjusts skb_gso_segment() so that we can at least avoid such warnings on checksum. Cc: Jesse Gross Cc: David S. Miller Signed-off-by: Cong Wang Signed-off-by: David S. Miller --- include/linux/netdevice.h | 11 +++++++++-- net/core/dev.c | 21 ++++++++++++++++----- net/openvswitch/datapath.c | 2 +- 3 files changed, 26 insertions(+), 8 deletions(-) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 85b0949d9946..ab2774eb49e8 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2662,8 +2662,15 @@ extern int netdev_master_upper_dev_link(struct net_device *dev, extern void netdev_upper_dev_unlink(struct net_device *dev, struct net_device *upper_dev); extern int skb_checksum_help(struct sk_buff *skb); -extern struct sk_buff *skb_gso_segment(struct sk_buff *skb, - netdev_features_t features); +extern struct sk_buff *__skb_gso_segment(struct sk_buff *skb, + netdev_features_t features, bool tx_path); + +static inline +struct sk_buff *skb_gso_segment(struct sk_buff *skb, netdev_features_t features) +{ + return __skb_gso_segment(skb, features, true); +} + #ifdef CONFIG_BUG extern void netdev_rx_csum_fault(struct net_device *dev); #else diff --git a/net/core/dev.c b/net/core/dev.c index 2b275a7b8677..65da698c500b 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2327,18 +2327,29 @@ int skb_checksum_help(struct sk_buff *skb) } EXPORT_SYMBOL(skb_checksum_help); +/* openvswitch calls this on rx path, so we need a different check. + */ +static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path) +{ + if (tx_path) + return skb->ip_summed != CHECKSUM_PARTIAL; + else + return skb->ip_summed == CHECKSUM_NONE; +} + /** - * skb_gso_segment - Perform segmentation on skb. + * __skb_gso_segment - Perform segmentation on skb. * @skb: buffer to segment * @features: features for the output path (see dev->features) + * @tx_path: whether it is called in TX path * * This function segments the given skb and returns a list of segments. * * It may return NULL if the skb requires no segmentation. This is * only possible when GSO is used for verifying header integrity. */ -struct sk_buff *skb_gso_segment(struct sk_buff *skb, - netdev_features_t features) +struct sk_buff *__skb_gso_segment(struct sk_buff *skb, + netdev_features_t features, bool tx_path) { struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT); struct packet_offload *ptype; @@ -2361,7 +2372,7 @@ struct sk_buff *skb_gso_segment(struct sk_buff *skb, skb->mac_len = skb->network_header - skb->mac_header; __skb_pull(skb, skb->mac_len); - if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) { + if (unlikely(skb_needs_check(skb, tx_path))) { skb_warn_bad_offload(skb); if (skb_header_cloned(skb) && @@ -2390,7 +2401,7 @@ struct sk_buff *skb_gso_segment(struct sk_buff *skb, return segs; } -EXPORT_SYMBOL(skb_gso_segment); +EXPORT_SYMBOL(__skb_gso_segment); /* Take action when hardware reception checksum errors are detected. */ #ifdef CONFIG_BUG diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c index d8c13a965459..9dc537df46c4 100644 --- a/net/openvswitch/datapath.c +++ b/net/openvswitch/datapath.c @@ -301,7 +301,7 @@ static int queue_gso_packets(struct net *net, int dp_ifindex, struct sk_buff *segs, *nskb; int err; - segs = skb_gso_segment(skb, NETIF_F_SG | NETIF_F_HW_CSUM); + segs = __skb_gso_segment(skb, NETIF_F_SG | NETIF_F_HW_CSUM, false); if (IS_ERR(segs)) return PTR_ERR(segs);