From c1f90e07a6733dd4399bbb47ed6d63c6fa07573f Mon Sep 17 00:00:00 2001 From: Simon Horman Date: Tue, 24 Sep 2013 16:44:06 +0900 Subject: [PATCH] datapath: Move segmentation compatibility code into a compatibility function Move segmentation compatibility code out of netdev_send and into rpl_dev_queue_xmit(), a compatibility function used in place of dev_queue_xmit() as necessary. As suggested by Jesse Gross. Some minor though verbose implementation notes: * This rpl_dev_queue_xmit() endeavours to return a valid error code or zero on success as per dev_queue_xmit(). The exception is that when dev_queue_xmit() is called in a loop only the status of the last call is taken into account, thus ignoring any errors returned by previous calls. This is derived from the previous calls to dev_queue_xmit() in a loop where netdev_send() ignores the return value of dev_queue_xmit() entirely. * netdev_send() continues to ignore the value of dev_queue_xmit(). So the discussion of the return value of rpl_dev_queue_xmit() above is has no bearing on run-time behaviour. * The return value of netdev_send() may differ from the previous implementation in the case where segmentation is performed before calling the real dev_queue_xmit(). This is because previously in this case netdev_send() would return the combined length of the skbs resulting from segmentation. Whereas the current code always returns the length of the original skb. Signed-off-by: Simon Horman [jesse: adjust error path in netdev_send() to match upstream] Signed-off-by: Jesse Gross --- datapath/linux/compat/gso.c | 80 +++++++++++++++++++ .../linux/compat/include/linux/netdevice.h | 5 ++ datapath/vport-netdev.c | 71 ---------------- 3 files changed, 85 insertions(+), 71 deletions(-) diff --git a/datapath/linux/compat/gso.c b/datapath/linux/compat/gso.c index 30332a2dc..32f906c82 100644 --- a/datapath/linux/compat/gso.c +++ b/datapath/linux/compat/gso.c @@ -36,6 +36,86 @@ #include "gso.h" +#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,37) && \ + !defined(HAVE_VLAN_BUG_WORKAROUND) +#include + +static int vlan_tso __read_mostly; +module_param(vlan_tso, int, 0644); +MODULE_PARM_DESC(vlan_tso, "Enable TSO for VLAN packets"); +#else +#define vlan_tso true +#endif + +#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,37) +static bool dev_supports_vlan_tx(struct net_device *dev) +{ +#if defined(HAVE_VLAN_BUG_WORKAROUND) + return dev->features & NETIF_F_HW_VLAN_TX; +#else + /* Assume that the driver is buggy. */ + return false; +#endif +} + +int rpl_dev_queue_xmit(struct sk_buff *skb) +{ +#undef dev_queue_xmit + int err = -ENOMEM; + + if (vlan_tx_tag_present(skb) && !dev_supports_vlan_tx(skb->dev)) { + int features; + + features = netif_skb_features(skb); + + if (!vlan_tso) + features &= ~(NETIF_F_TSO | NETIF_F_TSO6 | + NETIF_F_UFO | NETIF_F_FSO); + + skb = __vlan_put_tag(skb, skb->vlan_proto, vlan_tx_tag_get(skb)); + if (unlikely(!skb)) + return err; + vlan_set_tci(skb, 0); + + if (netif_needs_gso(skb, features)) { + struct sk_buff *nskb; + + nskb = skb_gso_segment(skb, features); + if (!nskb) { + if (unlikely(skb_cloned(skb) && + pskb_expand_head(skb, 0, 0, GFP_ATOMIC))) + goto drop; + + skb_shinfo(skb)->gso_type &= ~SKB_GSO_DODGY; + goto xmit; + } + + if (IS_ERR(nskb)) { + err = PTR_ERR(nskb); + goto drop; + } + consume_skb(skb); + skb = nskb; + + do { + nskb = skb->next; + skb->next = NULL; + err = dev_queue_xmit(skb); + skb = nskb; + } while (skb); + + return err; + } + } +xmit: + return dev_queue_xmit(skb); + +drop: + kfree_skb(skb); + return err; +} +#endif /* kernel version < 2.6.37 */ + static __be16 __skb_network_protocol(struct sk_buff *skb) { __be16 type = skb->protocol; diff --git a/datapath/linux/compat/include/linux/netdevice.h b/datapath/linux/compat/include/linux/netdevice.h index 4e2b7f55a..2b2c85511 100644 --- a/datapath/linux/compat/include/linux/netdevice.h +++ b/datapath/linux/compat/include/linux/netdevice.h @@ -120,4 +120,9 @@ static inline void netdev_upper_dev_unlink(struct net_device *dev, } #endif +#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,37) +#define dev_queue_xmit rpl_dev_queue_xmit +int dev_queue_xmit(struct sk_buff *skb); +#endif + #endif diff --git a/datapath/vport-netdev.c b/datapath/vport-netdev.c index 31680fd7d..2a83f730a 100644 --- a/datapath/vport-netdev.c +++ b/datapath/vport-netdev.c @@ -34,17 +34,6 @@ #include "vport-internal_dev.h" #include "vport-netdev.h" -#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,37) && \ - !defined(HAVE_VLAN_BUG_WORKAROUND) -#include - -static int vlan_tso __read_mostly; -module_param(vlan_tso, int, 0644); -MODULE_PARM_DESC(vlan_tso, "Enable TSO for VLAN packets"); -#else -#define vlan_tso true -#endif - static void netdev_port_receive(struct vport *vport, struct sk_buff *skb); #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,39) @@ -259,19 +248,6 @@ static unsigned int packet_length(const struct sk_buff *skb) return length; } -static bool dev_supports_vlan_tx(struct net_device *dev) -{ -#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,37) - /* Software fallback means every device supports vlan_tci on TX. */ - return true; -#elif defined(HAVE_VLAN_BUG_WORKAROUND) - return dev->features & NETIF_F_HW_VLAN_TX; -#else - /* Assume that the driver is buggy. */ - return false; -#endif -} - static int netdev_send(struct vport *vport, struct sk_buff *skb) { struct netdev_vport *netdev_vport = netdev_vport_priv(vport); @@ -286,53 +262,6 @@ static int netdev_send(struct vport *vport, struct sk_buff *skb) } skb->dev = netdev_vport->dev; - - if (vlan_tx_tag_present(skb) && !dev_supports_vlan_tx(skb->dev)) { - int features; - - features = netif_skb_features(skb); - - if (!vlan_tso) - features &= ~(NETIF_F_TSO | NETIF_F_TSO6 | - NETIF_F_UFO | NETIF_F_FSO); - - skb = __vlan_put_tag(skb, skb->vlan_proto, vlan_tx_tag_get(skb)); - if (unlikely(!skb)) - return 0; - vlan_set_tci(skb, 0); - - if (netif_needs_gso(skb, features)) { - struct sk_buff *nskb; - - nskb = skb_gso_segment(skb, features); - if (!nskb) { - if (unlikely(skb_cloned(skb) && - pskb_expand_head(skb, 0, 0, GFP_ATOMIC))) - goto drop; - - skb_shinfo(skb)->gso_type &= ~SKB_GSO_DODGY; - goto xmit; - } - - if (IS_ERR(nskb)) - goto drop; - consume_skb(skb); - skb = nskb; - - len = 0; - do { - nskb = skb->next; - skb->next = NULL; - len += skb->len; - dev_queue_xmit(skb); - skb = nskb; - } while (skb); - - return len; - } - } - -xmit: len = skb->len; dev_queue_xmit(skb); -- 2.43.0