Merge "citrix" branch into "master".
[sliver-openvswitch.git] / datapath / actions.c
index a037e43..bef7d10 100644 (file)
@@ -1,6 +1,6 @@
 /*
  * Distributed under the terms of the GNU GPL version 2.
- * Copyright (c) 2007, 2008, 2009 Nicira Networks.
+ * Copyright (c) 2007, 2008, 2009, 2010 Nicira Networks.
  *
  * Significant portions of this file may be copied from parts of the Linux
  * kernel, by Linus Torvalds and others.
@@ -15,6 +15,7 @@
 #include <linux/udp.h>
 #include <linux/in6.h>
 #include <linux/if_vlan.h>
+#include <net/inet_ecn.h>
 #include <net/ip.h>
 #include <net/checksum.h>
 #include "datapath.h"
 #include "actions.h"
 #include "openvswitch/datapath-protocol.h"
 
-struct sk_buff *
-make_writable(struct sk_buff *skb, gfp_t gfp)
+static struct sk_buff *
+make_writable(struct sk_buff *skb, unsigned min_headroom, gfp_t gfp)
 {
        if (skb_shared(skb) || skb_cloned(skb)) {
-               struct sk_buff *nskb = skb_copy(skb, gfp);
+               struct sk_buff *nskb;
+               unsigned headroom = max(min_headroom, skb_headroom(skb));
+
+               nskb = skb_copy_expand(skb, headroom, skb_tailroom(skb), gfp);
                if (nskb) {
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,24)
+                       /* Before 2.6.24 these fields were not copied when
+                        * doing an skb_copy_expand. */
+                       nskb->ip_summed = skb->ip_summed;
+                       nskb->csum = skb->csum;
+#endif
+#if defined(CONFIG_XEN) && defined(HAVE_PROTO_DATA_VALID)
+                       /* These fields are copied in skb_clone but not in
+                        * skb_copy or related functions.  We need to manually
+                        * copy them over here. */
+                       nskb->proto_data_valid = skb->proto_data_valid;
+                       nskb->proto_csum_blank = skb->proto_csum_blank;
+#endif
                        kfree_skb(skb);
                        return nskb;
                }
@@ -48,11 +65,14 @@ vlan_pull_tag(struct sk_buff *skb)
        struct vlan_ethhdr *vh = vlan_eth_hdr(skb);
        struct ethhdr *eh;
 
-
        /* Verify we were given a vlan packet */
        if (vh->h_vlan_proto != htons(ETH_P_8021Q))
                return skb;
 
+       if (OVS_CB(skb)->ip_summed == OVS_CSUM_COMPLETE)
+               skb->csum = csum_sub(skb->csum, csum_partial(skb->data
+                                       + ETH_HLEN, VLAN_HLEN, 0));
+
        memmove(skb->data + VLAN_HLEN, skb->data, 2 * VLAN_ETH_ALEN);
 
        eh = (struct ethhdr *)skb_pull(skb, VLAN_HLEN);
@@ -74,20 +94,30 @@ modify_vlan_tci(struct datapath *dp, struct sk_buff *skb,
        if (a->type == ODPAT_SET_VLAN_VID) {
                tci = ntohs(a->vlan_vid.vlan_vid);
                mask = VLAN_VID_MASK;
-               key->dl_vlan = htons(tci & mask);
+               key->dl_vlan = a->vlan_vid.vlan_vid;
        } else {
-               tci = a->vlan_pcp.vlan_pcp << 13;
+               tci = a->vlan_pcp.vlan_pcp << VLAN_PCP_SHIFT;
                mask = VLAN_PCP_MASK;
+               key->dl_vlan_pcp = a->vlan_pcp.vlan_pcp;
        }
 
-       skb = make_writable(skb, gfp);
+       skb = make_writable(skb, VLAN_HLEN, gfp);
        if (!skb)
                return ERR_PTR(-ENOMEM);
 
        if (skb->protocol == htons(ETH_P_8021Q)) {
                /* Modify vlan id, but maintain other TCI values */
                struct vlan_ethhdr *vh = vlan_eth_hdr(skb);
+               __be16 old_tci = vh->h_vlan_TCI;
+
                vh->h_vlan_TCI = htons((ntohs(vh->h_vlan_TCI) & ~mask) | tci);
+
+               if (OVS_CB(skb)->ip_summed == OVS_CSUM_COMPLETE) {
+                       __be16 diff[] = { ~old_tci, vh->h_vlan_TCI };
+
+                       skb->csum = ~csum_partial((char *)diff, sizeof(diff),
+                                               ~skb->csum);
+               }
        } else {
                /* Add vlan header */
 
@@ -96,7 +126,7 @@ modify_vlan_tci(struct datapath *dp, struct sk_buff *skb,
                 * when we send the packet out on the wire, and it will fail at
                 * that point because skb_checksum_setup() will not look inside
                 * an 802.1Q header. */
-               skb_checksum_setup(skb);
+               vswitch_skb_checksum_setup(skb);
 
                /* GSO is not implemented for packets with an 802.1Q header, so
                 * we have to do segmentation before we add that header.
@@ -127,6 +157,9 @@ modify_vlan_tci(struct datapath *dp, struct sk_buff *skb,
 
                                segs->next = NULL;
 
+                               /* GSO can change the checksum type so update.*/
+                               compute_ip_summed(segs, true);
+
                                segs = __vlan_put_tag(segs, tci);
                                err = -ENOMEM;
                                if (segs) {
@@ -150,6 +183,7 @@ modify_vlan_tci(struct datapath *dp, struct sk_buff *skb,
                        } while (segs->next);
 
                        skb = segs;
+                       compute_ip_summed(skb, true);
                }
 
                /* The hardware-accelerated version of vlan_put_tag() works
@@ -160,6 +194,12 @@ modify_vlan_tci(struct datapath *dp, struct sk_buff *skb,
                skb = __vlan_put_tag(skb, tci);
                if (!skb)
                        return ERR_PTR(-ENOMEM);
+
+               /* GSO doesn't fix up the hardware computed checksum so this
+                * will only be hit in the non-GSO case. */
+               if (OVS_CB(skb)->ip_summed == OVS_CSUM_COMPLETE)
+                       skb->csum = csum_add(skb->csum, csum_partial(skb->data
+                                               + ETH_HLEN, VLAN_HLEN, 0));
        }
 
        return skb;
@@ -168,7 +208,7 @@ modify_vlan_tci(struct datapath *dp, struct sk_buff *skb,
 static struct sk_buff *strip_vlan(struct sk_buff *skb,
                                  struct odp_flow_key *key, gfp_t gfp)
 {
-       skb = make_writable(skb, gfp);
+       skb = make_writable(skb, 0, gfp);
        if (skb) {
                vlan_pull_tag(skb);
                key->dl_vlan = htons(ODP_VLAN_NONE);
@@ -177,14 +217,20 @@ static struct sk_buff *strip_vlan(struct sk_buff *skb,
 }
 
 static struct sk_buff *set_dl_addr(struct sk_buff *skb,
+                                  struct odp_flow_key *key,
                                   const struct odp_action_dl_addr *a,
                                   gfp_t gfp)
 {
-       skb = make_writable(skb, gfp);
+       skb = make_writable(skb, 0, gfp);
        if (skb) {
                struct ethhdr *eh = eth_hdr(skb);
-               memcpy(a->type == ODPAT_SET_DL_SRC ? eh->h_source : eh->h_dest,
-                      a->dl_addr, ETH_ALEN);
+               if (a->type == ODPAT_SET_DL_SRC) {
+                       memcpy(eh->h_source, a->dl_addr, ETH_ALEN);
+                       memcpy(key->dl_src, a->dl_addr, ETH_ALEN);
+               } else {
+                       memcpy(eh->h_dest, a->dl_addr, ETH_ALEN);
+                       memcpy(key->dl_dst, a->dl_addr, ETH_ALEN);
+               }
        }
        return skb;
 }
@@ -197,10 +243,11 @@ static void update_csum(__sum16 *sum, struct sk_buff *skb,
                        __be32 from, __be32 to, int pseudohdr)
 {
        __be32 diff[] = { ~from, to };
-       if (skb->ip_summed != CHECKSUM_PARTIAL) {
+
+       if (OVS_CB(skb)->ip_summed != OVS_CSUM_PARTIAL) {
                *sum = csum_fold(csum_partial((char *)diff, sizeof(diff),
                                ~csum_unfold(*sum)));
-               if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
+               if (OVS_CB(skb)->ip_summed == OVS_CSUM_COMPLETE && pseudohdr)
                        skb->csum = ~csum_partial((char *)diff, sizeof(diff),
                                                ~skb->csum);
        } else if (pseudohdr)
@@ -216,7 +263,7 @@ static struct sk_buff *set_nw_addr(struct sk_buff *skb,
        if (key->dl_type != htons(ETH_P_IP))
                return skb;
 
-       skb = make_writable(skb, gfp);
+       skb = make_writable(skb, 0, gfp);
        if (skb) {
                struct iphdr *nh = ip_hdr(skb);
                u32 *f = a->type == ODPAT_SET_NW_SRC ? &nh->saddr : &nh->daddr;
@@ -232,6 +279,36 @@ static struct sk_buff *set_nw_addr(struct sk_buff *skb,
                }
                update_csum(&nh->check, skb, old, new, 0);
                *f = new;
+
+               if (a->type == ODPAT_SET_NW_SRC)
+                       key->nw_src = a->nw_addr;
+               else
+                       key->nw_dst = a->nw_addr;
+       }
+       return skb;
+}
+
+static struct sk_buff *set_nw_tos(struct sk_buff *skb,
+                                  struct odp_flow_key *key,
+                                  const struct odp_action_nw_tos *a,
+                                  gfp_t gfp)
+{
+       if (key->dl_type != htons(ETH_P_IP))
+               return skb;
+
+       skb = make_writable(skb, 0, gfp);
+       if (skb) {
+               struct iphdr *nh = ip_hdr(skb);
+               u8 *f = &nh->tos;
+               u8 old = *f;
+               u8 new;
+
+               /* Set the DSCP bits and preserve the ECN bits. */
+               new = a->nw_tos | (nh->tos & INET_ECN_MASK);
+               update_csum(&nh->check, skb, htons((uint16_t)old),
+                               htons((uint16_t)new), 0);
+               *f = new;
+               key->nw_tos = a->nw_tos;
        }
        return skb;
 }
@@ -253,15 +330,19 @@ set_tp_port(struct sk_buff *skb, struct odp_flow_key *key,
        else
                return skb;
 
-       skb = make_writable(skb, gfp);
+       skb = make_writable(skb, 0, gfp);
        if (skb) {
                struct udphdr *th = udp_hdr(skb);
                u16 *f = a->type == ODPAT_SET_TP_SRC ? &th->source : &th->dest;
                u16 old = *f;
                u16 new = a->tp_port;
-               update_csum((u16*)((u8*)skb->data + check_ofs),
-                           skb, old, new, 1);
+               update_csum((u16*)(skb_transport_header(skb) + check_ofs), 
+                               skb, old, new, 0);
                *f = new;
+               if (a->type == ODPAT_SET_TP_SRC)
+                       key->tp_src = a->tp_port;
+               else
+                       key->tp_dst = a->tp_port;
        }
        return skb;
 }
@@ -286,6 +367,7 @@ int dp_xmit_skb(struct sk_buff *skb)
                return -E2BIG;
        }
 
+       forward_ip_summed(skb);
        dev_queue_xmit(skb);
 
        return len;
@@ -307,7 +389,7 @@ do_output(struct datapath *dp, struct sk_buff *skb, int out_port)
        dev = skb->dev = p->dev;
        if (is_dp_dev(dev))
                dp_dev_recv(dev, skb);
-        else
+       else
                dp_xmit_skb(skb);
        return;
 
@@ -350,6 +432,28 @@ output_control(struct datapath *dp, struct sk_buff *skb, u32 arg, gfp_t gfp)
        return dp_output_control(dp, skb, _ODPL_ACTION_NR, arg);
 }
 
+/* Send a copy of this packet up to the sFlow agent, along with extra
+ * information about what happened to it. */
+static void sflow_sample(struct datapath *dp, struct sk_buff *skb,
+                        const union odp_action *a, int n_actions,
+                        gfp_t gfp, struct net_bridge_port *nbp)
+{
+       struct odp_sflow_sample_header *hdr;
+       unsigned int actlen = n_actions * sizeof(union odp_action);
+       unsigned int hdrlen = sizeof(struct odp_sflow_sample_header);
+       struct sk_buff *nskb;
+
+       nskb = skb_copy_expand(skb, actlen + hdrlen, 0, gfp);
+       if (!nskb)
+               return;
+
+       memcpy(__skb_push(nskb, actlen), a, actlen);
+       hdr = (struct odp_sflow_sample_header*)__skb_push(nskb, hdrlen);
+       hdr->n_actions = n_actions;
+       hdr->sample_pool = atomic_read(&nbp->sflow_pool);
+       dp_output_control(dp, nskb, _ODPL_SFLOW_NR, 0);
+}
+
 /* Execute a list of actions against 'skb'. */
 int execute_actions(struct datapath *dp, struct sk_buff *skb,
                    struct odp_flow_key *key,
@@ -361,7 +465,18 @@ int execute_actions(struct datapath *dp, struct sk_buff *skb,
         * then freeing the original skbuff is wasteful.  So the following code
         * is slightly obscure just to avoid that. */
        int prev_port = -1;
-       int err = 0;
+       int err;
+
+       if (dp->sflow_probability) {
+               struct net_bridge_port *p = skb->dev->br_port;
+               if (p) {
+                       atomic_inc(&p->sflow_pool);
+                       if (dp->sflow_probability == UINT_MAX ||
+                           net_random() < dp->sflow_probability)
+                               sflow_sample(dp, skb, a, n_actions, gfp, p);
+               }
+       }
+
        for (; n_actions > 0; a++, n_actions--) {
                WARN_ON_ONCE(skb_shared(skb));
                if (prev_port != -1) {
@@ -400,7 +515,7 @@ int execute_actions(struct datapath *dp, struct sk_buff *skb,
 
                case ODPAT_SET_DL_SRC:
                case ODPAT_SET_DL_DST:
-                       skb = set_dl_addr(skb, &a->dl_addr, gfp);
+                       skb = set_dl_addr(skb, key, &a->dl_addr, gfp);
                        break;
 
                case ODPAT_SET_NW_SRC:
@@ -408,6 +523,10 @@ int execute_actions(struct datapath *dp, struct sk_buff *skb,
                        skb = set_nw_addr(skb, key, &a->nw_addr, gfp);
                        break;
 
+               case ODPAT_SET_NW_TOS:
+                       skb = set_nw_tos(skb, key, &a->nw_tos, gfp);
+                       break;
+
                case ODPAT_SET_TP_SRC:
                case ODPAT_SET_TP_DST:
                        skb = set_tp_port(skb, key, &a->tp_port, gfp);
@@ -420,5 +539,5 @@ int execute_actions(struct datapath *dp, struct sk_buff *skb,
                do_output(dp, skb, prev_port);
        else
                kfree_skb(skb);
-       return err;
+       return 0;
 }