diff options
Diffstat (limited to 'datapath')
| -rw-r--r-- | datapath/checksum.c | 226 | ||||
| -rw-r--r-- | datapath/checksum.h | 94 | ||||
| -rw-r--r-- | datapath/datapath.c | 8 | ||||
| -rw-r--r-- | datapath/datapath.h | 7 | ||||
| -rw-r--r-- | datapath/tunnel.c | 33 | ||||
| -rw-r--r-- | datapath/vport-internal_dev.c | 7 | ||||
| -rw-r--r-- | datapath/vport-netdev.c | 15 |
7 files changed, 257 insertions, 133 deletions
diff --git a/datapath/checksum.c b/datapath/checksum.c index e35194916..3a131f4e2 100644 --- a/datapath/checksum.c +++ b/datapath/checksum.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2010 Nicira Networks. + * Copyright (c) 2010, 2011 Nicira Networks. * Distributed under the terms of the GNU GPL version 2. * * Significant portions of this file may be copied from parts of the Linux @@ -16,7 +16,82 @@ #include "checksum.h" #include "datapath.h" - /* Types of checksums that we can receive (these all refer to L4 checksums): +#ifdef NEED_CSUM_NORMALIZE + +#if defined(CONFIG_XEN) && defined(HAVE_PROTO_DATA_VALID) +/* This code is based on skb_checksum_setup() from Xen's net/dev/core.c. We + * can't call this function directly because it isn't exported in all + * versions. */ +static int vswitch_skb_checksum_setup(struct sk_buff *skb) +{ + struct iphdr *iph; + unsigned char *th; + int err = -EPROTO; + __u16 csum_start, csum_offset; + + if (!skb->proto_csum_blank) + return 0; + + if (skb->protocol != htons(ETH_P_IP)) + goto out; + + if (!pskb_may_pull(skb, skb_network_header(skb) + sizeof(struct iphdr) - skb->data)) + goto out; + + iph = ip_hdr(skb); + th = skb_network_header(skb) + 4 * iph->ihl; + + csum_start = th - skb->head; + switch (iph->protocol) { + case IPPROTO_TCP: + csum_offset = offsetof(struct tcphdr, check); + break; + case IPPROTO_UDP: + csum_offset = offsetof(struct udphdr, check); + break; + default: + if (net_ratelimit()) + pr_err("Attempting to checksum a non-TCP/UDP packet, " + "dropping a protocol %d packet", + iph->protocol); + goto out; + } + + if (!pskb_may_pull(skb, th + csum_offset + 2 - skb->data)) + goto out; + + skb->proto_csum_blank = 0; + set_ip_summed(skb, OVS_CSUM_PARTIAL); + set_skb_csum_pointers(skb, csum_start, csum_offset); + + err = 0; + +out: + return err; +} +#else +static int vswitch_skb_checksum_setup(struct sk_buff *skb) +{ + return 0; +} +#endif /* not Xen old style checksums */ + +/* + * compute_ip_summed - map external checksum state onto OVS representation + * + * @skb: Packet to manipulate. + * @xmit: Whether we were on transmit path of network stack. For example, + * this is true for the internal dev vport because it receives skbs + * that passed through dev_queue_xmit() but false for the netdev vport + * because its packets come from netif_receive_skb(). + * + * Older kernels (and various versions of Xen) were not explicit enough about + * checksum offload parameters and rely on a combination of context and + * non standard fields. This deals with all those variations so that we + * can internally manipulate checksum offloads without worrying about kernel + * version. + * + * Types of checksums that we can receive (these all refer to L4 checksums): * 1. CHECKSUM_NONE: Device that did not compute checksum, contains full * (though not verified) checksum in packet but not in skb->csum. Packets * from the bridge local port will also have this type. @@ -58,25 +133,24 @@ * CHECKSUM_PARTIAL, it will be sent with the wrong checksum. However, there * shouldn't be any devices that do this with bridging. */ -#ifdef NEED_CSUM_NORMALIZE -void compute_ip_summed(struct sk_buff *skb, bool xmit) +int compute_ip_summed(struct sk_buff *skb, bool xmit) { /* For our convenience these defines change repeatedly between kernel * versions, so we can't just copy them over... */ switch (skb->ip_summed) { case CHECKSUM_NONE: - OVS_CB(skb)->ip_summed = OVS_CSUM_NONE; + set_ip_summed(skb, OVS_CSUM_NONE); break; case CHECKSUM_UNNECESSARY: - OVS_CB(skb)->ip_summed = OVS_CSUM_UNNECESSARY; + set_ip_summed(skb, OVS_CSUM_UNNECESSARY); break; #ifdef CHECKSUM_HW /* In theory this could be either CHECKSUM_PARTIAL or CHECKSUM_COMPLETE. * However, on the receive side we should only get CHECKSUM_PARTIAL * packets from Xen, which uses some special fields to represent this - * (see below). Since we can only make one type work, pick the one - * that actually happens in practice. + * (see vswitch_skb_checksum_setup()). Since we can only make one type work, + * pick the one that actually happens in practice. * * On the transmit side (basically after skb_checksum_setup() * has been run or on internal dev transmit), packets with @@ -84,87 +158,101 @@ void compute_ip_summed(struct sk_buff *skb, bool xmit) */ case CHECKSUM_HW: if (!xmit) - OVS_CB(skb)->ip_summed = OVS_CSUM_COMPLETE; + set_ip_summed(skb, OVS_CSUM_COMPLETE); else - OVS_CB(skb)->ip_summed = OVS_CSUM_PARTIAL; - + set_ip_summed(skb, OVS_CSUM_PARTIAL); break; #else case CHECKSUM_COMPLETE: - OVS_CB(skb)->ip_summed = OVS_CSUM_COMPLETE; + set_ip_summed(skb, OVS_CSUM_COMPLETE); break; case CHECKSUM_PARTIAL: - OVS_CB(skb)->ip_summed = OVS_CSUM_PARTIAL; + set_ip_summed(skb, OVS_CSUM_PARTIAL); break; #endif } -#if defined(CONFIG_XEN) && defined(HAVE_PROTO_DATA_VALID) - /* Xen has a special way of representing CHECKSUM_PARTIAL on older - * kernels. It should not be set on the transmit path though. - */ - if (skb->proto_csum_blank) - OVS_CB(skb)->ip_summed = OVS_CSUM_PARTIAL; + OVS_CB(skb)->csum_start = skb_headroom(skb) + skb_transport_offset(skb); - WARN_ON_ONCE(skb->proto_csum_blank && xmit); -#endif + return vswitch_skb_checksum_setup(skb); } -u8 get_ip_summed(struct sk_buff *skb) +/* + * forward_ip_summed - map internal checksum state back onto native kernel fields + * + * @skb: Packet to manipulate. + * @xmit: Whether we are about send on the transmit path the network stack. This + * follows the same logic as the @xmit field in compute_ip_summed(). + * Generally, a given vport will have opposite values for @xmit passed to these + * two functions. + * + * When a packet is about to egress from OVS take our internal fields (including + * any modifications we have made) and recreate the correct representation for + * this kernel. This may do things like change the transport header offset. + */ +void forward_ip_summed(struct sk_buff *skb, bool xmit) { - return OVS_CB(skb)->ip_summed; -} -#endif /* NEED_CSUM_NORMALIZE */ - + switch(get_ip_summed(skb)) { + case OVS_CSUM_NONE: + skb->ip_summed = CHECKSUM_NONE; + break; + case OVS_CSUM_UNNECESSARY: + skb->ip_summed = CHECKSUM_UNNECESSARY; #if defined(CONFIG_XEN) && defined(HAVE_PROTO_DATA_VALID) -/* This code is based on skb_checksum_setup() from Xen's net/dev/core.c. We - * can't call this function directly because it isn't exported in all - * versions. */ -int vswitch_skb_checksum_setup(struct sk_buff *skb) -{ - struct iphdr *iph; - unsigned char *th; - int err = -EPROTO; - __u16 csum_start, csum_offset; - - if (!skb->proto_csum_blank) - return 0; - - if (skb->protocol != htons(ETH_P_IP)) - goto out; - - if (!pskb_may_pull(skb, skb_network_header(skb) + sizeof(struct iphdr) - skb->data)) - goto out; - - iph = ip_hdr(skb); - th = skb_network_header(skb) + 4 * iph->ihl; - - csum_start = th - skb->head; - switch (iph->protocol) { - case IPPROTO_TCP: - csum_offset = offsetof(struct tcphdr, check); + skb->proto_data_valid = 1; +#endif break; - case IPPROTO_UDP: - csum_offset = offsetof(struct udphdr, check); +#ifdef CHECKSUM_HW + case OVS_CSUM_COMPLETE: + if (!xmit) + skb->ip_summed = CHECKSUM_HW; + else + skb->ip_summed = CHECKSUM_NONE; break; - default: - if (net_ratelimit()) - pr_err("Attempting to checksum a non-TCP/UDP packet, " - "dropping a protocol %d packet", - iph->protocol); - goto out; + case OVS_CSUM_PARTIAL: + if (!xmit) { + skb->ip_summed = CHECKSUM_UNNECESSARY; +#if defined(CONFIG_XEN) && defined(HAVE_PROTO_DATA_VALID) + skb->proto_csum_blank = 1; +#endif + } else { + skb->ip_summed = CHECKSUM_HW; + } + break; +#else + case OVS_CSUM_COMPLETE: + skb->ip_summed = CHECKSUM_COMPLETE; + break; + case OVS_CSUM_PARTIAL: + skb->ip_summed = CHECKSUM_PARTIAL; + break; +#endif } - if (!pskb_may_pull(skb, th + csum_offset + 2 - skb->data)) - goto out; + if (get_ip_summed(skb) == OVS_CSUM_PARTIAL) + skb_set_transport_header(skb, OVS_CB(skb)->csum_start - skb_headroom(skb)); +} - skb->ip_summed = CHECKSUM_PARTIAL; - skb->proto_csum_blank = 0; - set_skb_csum_pointers(skb, csum_start, csum_offset); +u8 get_ip_summed(struct sk_buff *skb) +{ + return OVS_CB(skb)->ip_summed; +} - err = 0; +void set_ip_summed(struct sk_buff *skb, u8 ip_summed) +{ + OVS_CB(skb)->ip_summed = ip_summed; +} -out: - return err; +void get_skb_csum_pointers(const struct sk_buff *skb, u16 *csum_start, + u16 *csum_offset) +{ + *csum_start = OVS_CB(skb)->csum_start; + *csum_offset = skb->csum; } -#endif /* CONFIG_XEN && HAVE_PROTO_DATA_VALID */ + +void set_skb_csum_pointers(struct sk_buff *skb, u16 csum_start, u16 csum_offset) +{ + OVS_CB(skb)->csum_start = csum_start; + skb->csum = csum_offset; +} +#endif /* NEED_CSUM_NORMALIZE */ diff --git a/datapath/checksum.h b/datapath/checksum.h index abd461505..4f85104a7 100644 --- a/datapath/checksum.h +++ b/datapath/checksum.h @@ -1,5 +1,5 @@ /* - * Copyright (c) 2010 Nicira Networks. + * Copyright (c) 2010, 2011 Nicira Networks. * Distributed under the terms of the GNU GPL version 2. * * Significant portions of this file may be copied from parts of the Linux @@ -28,66 +28,50 @@ enum csum_type { }; #ifdef NEED_CSUM_NORMALIZE -void compute_ip_summed(struct sk_buff *skb, bool xmit); +int compute_ip_summed(struct sk_buff *skb, bool xmit); +void forward_ip_summed(struct sk_buff *skb, bool xmit); u8 get_ip_summed(struct sk_buff *skb); +void set_ip_summed(struct sk_buff *skb, u8 ip_summed); +void get_skb_csum_pointers(const struct sk_buff *skb, u16 *csum_start, + u16 *csum_offset); +void set_skb_csum_pointers(struct sk_buff *skb, u16 csum_start, u16 csum_offset); #else -static inline void compute_ip_summed(struct sk_buff *skb, bool xmit) { } -static inline u8 get_ip_summed(struct sk_buff *skb) +static inline int compute_ip_summed(struct sk_buff *skb, bool xmit) { - return skb->ip_summed; + return 0; } -#endif -/* This function closely resembles skb_forward_csum() used by the bridge. It - * is slightly different because we are only concerned with bridging and not - * other types of forwarding and can get away with slightly more optimal - * behavior. - */ -static inline void forward_ip_summed(struct sk_buff *skb) +static inline void forward_ip_summed(struct sk_buff *skb, bool xmit) { } + +static inline u8 get_ip_summed(struct sk_buff *skb) { -#ifdef CHECKSUM_HW - if (get_ip_summed(skb) == OVS_CSUM_COMPLETE) - skb->ip_summed = CHECKSUM_NONE; -#endif + return skb->ip_summed; } -#if defined(CONFIG_XEN) && defined(HAVE_PROTO_DATA_VALID) -int vswitch_skb_checksum_setup(struct sk_buff *skb); -#else -static inline int vswitch_skb_checksum_setup(struct sk_buff *skb) +static inline void set_ip_summed(struct sk_buff *skb, u8 ip_summed) { - return 0; + skb->ip_summed = ip_summed; } -#endif static inline void get_skb_csum_pointers(const struct sk_buff *skb, u16 *csum_start, u16 *csum_offset) { -#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22) *csum_start = skb->csum_start; *csum_offset = skb->csum_offset; -#else - *csum_start = skb_headroom(skb) + skb_transport_offset(skb); - *csum_offset = skb->csum; -#endif } static inline void set_skb_csum_pointers(struct sk_buff *skb, u16 csum_start, u16 csum_offset) { -#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22) skb->csum_start = csum_start; skb->csum_offset = csum_offset; -#else - skb_set_transport_header(skb, csum_start - skb_headroom(skb)); - skb->csum = csum_offset; -#endif } +#endif -#if defined(NEED_CSUM_NORMALIZE) || LINUX_VERSION_CODE < KERNEL_VERSION(2,6,25) /* This is really compatibility code that belongs in the compat directory. * However, it needs access to our normalized checksum values, so put it here. */ +#if defined(NEED_CSUM_NORMALIZE) || LINUX_VERSION_CODE < KERNEL_VERSION(2,6,25) #define inet_proto_csum_replace4 rpl_inet_proto_csum_replace4 static inline void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb, __be32 from, __be32 to, @@ -107,4 +91,48 @@ static inline void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb, } #endif +#ifdef NEED_CSUM_NORMALIZE +static inline void update_csum_start(struct sk_buff *skb, int delta) +{ + if (get_ip_summed(skb) == OVS_CSUM_PARTIAL) { + u16 csum_start, csum_offset; + + get_skb_csum_pointers(skb, &csum_start, &csum_offset); + set_skb_csum_pointers(skb, csum_start + delta, csum_offset); + } +} + +static inline int rpl_pskb_expand_head(struct sk_buff *skb, int nhead, + int ntail, gfp_t gfp_mask) +{ + int err; + int old_headroom = skb_headroom(skb); + + err = pskb_expand_head(skb, nhead, ntail, gfp_mask); + if (unlikely(err)) + return err; + + update_csum_start(skb, skb_headroom(skb) - old_headroom); + + return 0; +} +#define pskb_expand_head rpl_pskb_expand_head + +static inline unsigned char *rpl__pskb_pull_tail(struct sk_buff *skb, + int delta) +{ + unsigned char *ret; + int old_headroom = skb_headroom(skb); + + ret = __pskb_pull_tail(skb, delta); + if (unlikely(!ret)) + return ret; + + update_csum_start(skb, skb_headroom(skb) - old_headroom); + + return ret; +} +#define __pskb_pull_tail rpl__pskb_pull_tail +#endif + #endif /* checksum.h */ diff --git a/datapath/datapath.c b/datapath/datapath.c index 534ab9143..566aeed6e 100644 --- a/datapath/datapath.c +++ b/datapath/datapath.c @@ -399,11 +399,7 @@ int dp_upcall(struct datapath *dp, struct sk_buff *skb, const struct dp_upcall_i WARN_ON_ONCE(skb_shared(skb)); - forward_ip_summed(skb); - - err = vswitch_skb_checksum_setup(skb); - if (err) - goto err_kfree_skb; + forward_ip_summed(skb, true); /* Break apart GSO packets into their component pieces. Otherwise * userspace may try to stuff a 64kB packet into a 1500-byte MTU. */ @@ -424,8 +420,6 @@ int dp_upcall(struct datapath *dp, struct sk_buff *skb, const struct dp_upcall_i return 0; -err_kfree_skb: - kfree_skb(skb); err: local_bh_disable(); stats = per_cpu_ptr(dp->stats_percpu, smp_processor_id()); diff --git a/datapath/datapath.h b/datapath/datapath.h index a0649064b..15a989892 100644 --- a/datapath/datapath.h +++ b/datapath/datapath.h @@ -102,9 +102,11 @@ struct datapath { * struct ovs_skb_cb - OVS data in skb CB * @vport: The datapath port on which the skb entered the switch. * @flow: The flow associated with this packet. May be %NULL if no flow. + * @tun_id: ID of the tunnel that encapsulated this packet. It is 0 if the * @ip_summed: Consistently stores L4 checksumming status across different * kernel versions. - * @tun_id: ID of the tunnel that encapsulated this packet. It is 0 if the + * @csum_start: Stores the offset from which to start checksumming independent + * of the transport header on all kernel versions. * packet was not received on a tunnel. * @vlan_tci: Provides a substitute for the skb->vlan_tci field on kernels * before 2.6.27. @@ -112,10 +114,11 @@ struct datapath { struct ovs_skb_cb { struct vport *vport; struct sw_flow *flow; + __be64 tun_id; #ifdef NEED_CSUM_NORMALIZE enum csum_type ip_summed; + u16 csum_start; #endif - __be64 tun_id; #ifdef NEED_VLAN_FIELD u16 vlan_tci; #endif diff --git a/datapath/tunnel.c b/datapath/tunnel.c index 2bf61597d..5c05c49ee 100644 --- a/datapath/tunnel.c +++ b/datapath/tunnel.c @@ -450,9 +450,13 @@ void tnl_rcv(struct vport *vport, struct sk_buff *skb, u8 tos) secpath_reset(skb); ecn_decapsulate(skb, tos); - compute_ip_summed(skb, false); vlan_set_tci(skb, 0); + if (unlikely(compute_ip_summed(skb, false))) { + kfree_skb(skb); + return; + } + vport_receive(vport, skb); } @@ -718,7 +722,11 @@ bool tnl_frag_needed(struct vport *vport, const struct tnl_mutable_config *mutab (TNL_F_IN_KEY_MATCH | TNL_F_OUT_KEY_ACTION)) OVS_CB(nskb)->tun_id = flow_key; - compute_ip_summed(nskb, false); + if (unlikely(compute_ip_summed(nskb, false))) { + kfree_skb(nskb); + return false; + } + vport_receive(vport, nskb); return true; @@ -1053,12 +1061,6 @@ static struct sk_buff *handle_offloads(struct sk_buff *skb, int min_headroom; int err; - forward_ip_summed(skb); - - err = vswitch_skb_checksum_setup(skb); - if (unlikely(err)) - goto error_free; - min_headroom = LL_RESERVED_SPACE(rt_dst(rt).dev) + rt_dst(rt).header_len + mutable->tunnel_hlen + (vlan_tx_tag_present(skb) ? VLAN_HLEN : 0); @@ -1073,6 +1075,8 @@ static struct sk_buff *handle_offloads(struct sk_buff *skb, goto error_free; } + forward_ip_summed(skb, true); + if (skb_is_gso(skb)) { struct sk_buff *nskb; @@ -1084,7 +1088,7 @@ static struct sk_buff *handle_offloads(struct sk_buff *skb, } skb = nskb; - } else if (skb->ip_summed == CHECKSUM_PARTIAL) { + } else if (get_ip_summed(skb) == OVS_CSUM_PARTIAL) { /* Pages aren't locked and could change at any time. * If this happens after we compute the checksum, the * checksum will be wrong. We linearize now to avoid @@ -1099,8 +1103,9 @@ static struct sk_buff *handle_offloads(struct sk_buff *skb, err = skb_checksum_help(skb); if (unlikely(err)) goto error_free; - } else if (skb->ip_summed == CHECKSUM_COMPLETE) - skb->ip_summed = CHECKSUM_NONE; + } + + set_ip_summed(skb, OVS_CSUM_NONE); return skb; @@ -1295,8 +1300,12 @@ int tnl_send(struct vport *vport, struct sk_buff *skb) ip_send_check(iph); if (cache_vport) { + if (unlikely(compute_ip_summed(skb, true))) { + kfree_skb(skb); + goto next; + } + OVS_CB(skb)->flow = cache->flow; - compute_ip_summed(skb, true); vport_receive(cache_vport, skb); sent_len += orig_len; } else { diff --git a/datapath/vport-internal_dev.c b/datapath/vport-internal_dev.c index fff4f4e59..b7bcbce6a 100644 --- a/datapath/vport-internal_dev.c +++ b/datapath/vport-internal_dev.c @@ -73,7 +73,11 @@ static int internal_dev_mac_addr(struct net_device *dev, void *p) /* Called with rcu_read_lock and bottom-halves disabled. */ static int internal_dev_xmit(struct sk_buff *skb, struct net_device *netdev) { - compute_ip_summed(skb, true); + if (unlikely(compute_ip_summed(skb, true))) { + kfree_skb(skb); + return 0; + } + vlan_copy_skb_tci(skb); OVS_CB(skb)->flow = NULL; @@ -252,6 +256,7 @@ static int internal_dev_recv(struct vport *vport, struct sk_buff *skb) skb->dev = netdev; skb->pkt_type = PACKET_HOST; skb->protocol = eth_type_trans(skb, netdev); + forward_ip_summed(skb, false); if (in_interrupt()) netif_rx(skb); diff --git a/datapath/vport-netdev.c b/datapath/vport-netdev.c index 3bab666c8..bc3108b95 100644 --- a/datapath/vport-netdev.c +++ b/datapath/vport-netdev.c @@ -284,7 +284,11 @@ static void netdev_port_receive(struct vport *vport, struct sk_buff *skb) skb_warn_if_lro(skb); skb_push(skb, ETH_HLEN); - compute_ip_summed(skb, false); + + if (unlikely(compute_ip_summed(skb, false))) { + kfree_skb(skb); + return; + } vlan_copy_skb_tci(skb); vport_receive(vport, skb); @@ -309,22 +313,15 @@ static int netdev_send(struct vport *vport, struct sk_buff *skb) int len; skb->dev = netdev_vport->dev; - forward_ip_summed(skb); + forward_ip_summed(skb, true); if (vlan_tx_tag_present(skb) && !dev_supports_vlan_tx(skb->dev)) { - int err; int features = 0; #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,26) features = skb->dev->features & skb->dev->vlan_features; #endif - err = vswitch_skb_checksum_setup(skb); - if (unlikely(err)) { - kfree_skb(skb); - return 0; - } - if (!vlan_tso) features &= ~(NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_UFO | NETIF_F_FSO); |