/* * Copyright (c) 2007, 2008, 2009, 2010 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 * kernel, by Linus Torvalds and others. */ /* Functions for managing the dp interface/device. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "openvswitch/datapath-protocol.h" #include "datapath.h" #include "actions.h" #include "dp_dev.h" #include "flow.h" #include "compat.h" int (*dp_ioctl_hook)(struct net_device *dev, struct ifreq *rq, int cmd); EXPORT_SYMBOL(dp_ioctl_hook); /* Datapaths. Protected on the read side by rcu_read_lock, on the write side * by dp_mutex. * * dp_mutex nests inside the RTNL lock: if you need both you must take the RTNL * lock first. * * It is safe to access the datapath and net_bridge_port structures with just * dp_mutex. */ static struct datapath *dps[ODP_MAX]; static DEFINE_MUTEX(dp_mutex); /* Number of milliseconds between runs of the maintenance thread. */ #define MAINT_SLEEP_MSECS 1000 static int new_nbp(struct datapath *, struct net_device *, int port_no); /* Must be called with rcu_read_lock or dp_mutex. */ struct datapath *get_dp(int dp_idx) { if (dp_idx < 0 || dp_idx >= ODP_MAX) return NULL; return rcu_dereference(dps[dp_idx]); } EXPORT_SYMBOL_GPL(get_dp); struct datapath *get_dp_locked(int dp_idx) { struct datapath *dp; mutex_lock(&dp_mutex); dp = get_dp(dp_idx); if (dp) mutex_lock(&dp->mutex); mutex_unlock(&dp_mutex); return dp; } static inline size_t br_nlmsg_size(void) { return NLMSG_ALIGN(sizeof(struct ifinfomsg)) + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */ + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */ + nla_total_size(4) /* IFLA_MASTER */ + nla_total_size(4) /* IFLA_MTU */ + nla_total_size(4) /* IFLA_LINK */ + nla_total_size(1); /* IFLA_OPERSTATE */ } static int dp_fill_ifinfo(struct sk_buff *skb, const struct net_bridge_port *port, int event, unsigned int flags) { const struct datapath *dp = port->dp; const struct net_device *dev = port->dev; struct ifinfomsg *hdr; struct nlmsghdr *nlh; nlh = nlmsg_put(skb, 0, 0, event, sizeof(*hdr), flags); if (nlh == NULL) return -EMSGSIZE; hdr = nlmsg_data(nlh); hdr->ifi_family = AF_BRIDGE; hdr->__ifi_pad = 0; hdr->ifi_type = dev->type; hdr->ifi_index = dev->ifindex; hdr->ifi_flags = dev_get_flags(dev); hdr->ifi_change = 0; NLA_PUT_STRING(skb, IFLA_IFNAME, dev->name); NLA_PUT_U32(skb, IFLA_MASTER, dp->ports[ODPP_LOCAL]->dev->ifindex); NLA_PUT_U32(skb, IFLA_MTU, dev->mtu); #ifdef IFLA_OPERSTATE NLA_PUT_U8(skb, IFLA_OPERSTATE, netif_running(dev) ? dev->operstate : IF_OPER_DOWN); #endif if (dev->addr_len) NLA_PUT(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr); if (dev->ifindex != dev->iflink) NLA_PUT_U32(skb, IFLA_LINK, dev->iflink); return nlmsg_end(skb, nlh); nla_put_failure: nlmsg_cancel(skb, nlh); return -EMSGSIZE; } static void dp_ifinfo_notify(int event, struct net_bridge_port *port) { struct net *net = dev_net(port->dev); struct sk_buff *skb; int err = -ENOBUFS; skb = nlmsg_new(br_nlmsg_size(), GFP_KERNEL); if (skb == NULL) goto errout; err = dp_fill_ifinfo(skb, port, event, 0); if (err < 0) { /* -EMSGSIZE implies BUG in br_nlmsg_size() */ WARN_ON(err == -EMSGSIZE); kfree_skb(skb); goto errout; } rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL, GFP_KERNEL); return; errout: if (err < 0) rtnl_set_sk_err(net, RTNLGRP_LINK, err); } static void release_dp(struct kobject *kobj) { struct datapath *dp = container_of(kobj, struct datapath, ifobj); kfree(dp); } struct kobj_type dp_ktype = { .release = release_dp }; static int create_dp(int dp_idx, const char __user *devnamep) { struct net_device *dp_dev; char devname[IFNAMSIZ]; struct datapath *dp; int err; int i; if (devnamep) { err = -EFAULT; if (strncpy_from_user(devname, devnamep, IFNAMSIZ - 1) < 0) goto err; devname[IFNAMSIZ - 1] = '\0'; } else { snprintf(devname, sizeof devname, "of%d", dp_idx); } rtnl_lock(); mutex_lock(&dp_mutex); err = -ENODEV; if (!try_module_get(THIS_MODULE)) goto err_unlock; /* Exit early if a datapath with that number already exists. * (We don't use -EEXIST because that's ambiguous with 'devname' * conflicting with an existing network device name.) */ err = -EBUSY; if (get_dp(dp_idx)) goto err_put_module; err = -ENOMEM; dp = kzalloc(sizeof *dp, GFP_KERNEL); if (dp == NULL) goto err_put_module; INIT_LIST_HEAD(&dp->port_list); mutex_init(&dp->mutex); dp->dp_idx = dp_idx; for (i = 0; i < DP_N_QUEUES; i++) skb_queue_head_init(&dp->queues[i]); init_waitqueue_head(&dp->waitqueue); /* Initialize kobject for bridge. This will be added as * /sys/class/net//brif later, if sysfs is enabled. */ dp->ifobj.kset = NULL; kobject_init(&dp->ifobj, &dp_ktype); /* Allocate table. */ err = -ENOMEM; rcu_assign_pointer(dp->table, dp_table_create(DP_L1_SIZE)); if (!dp->table) goto err_free_dp; /* Set up our datapath device. */ dp_dev = dp_dev_create(dp, devname, ODPP_LOCAL); err = PTR_ERR(dp_dev); if (IS_ERR(dp_dev)) goto err_destroy_table; err = new_nbp(dp, dp_dev, ODPP_LOCAL); if (err) { dp_dev_destroy(dp_dev); goto err_destroy_table; } dp->drop_frags = 0; dp->stats_percpu = alloc_percpu(struct dp_stats_percpu); if (!dp->stats_percpu) goto err_destroy_local_port; rcu_assign_pointer(dps[dp_idx], dp); mutex_unlock(&dp_mutex); rtnl_unlock(); dp_sysfs_add_dp(dp); return 0; err_destroy_local_port: dp_del_port(dp->ports[ODPP_LOCAL]); err_destroy_table: dp_table_destroy(dp->table, 0); err_free_dp: kfree(dp); err_put_module: module_put(THIS_MODULE); err_unlock: mutex_unlock(&dp_mutex); rtnl_unlock(); err: return err; } static void do_destroy_dp(struct datapath *dp) { struct net_bridge_port *p, *n; int i; list_for_each_entry_safe (p, n, &dp->port_list, node) if (p->port_no != ODPP_LOCAL) dp_del_port(p); dp_sysfs_del_dp(dp); rcu_assign_pointer(dps[dp->dp_idx], NULL); dp_del_port(dp->ports[ODPP_LOCAL]); dp_table_destroy(dp->table, 1); for (i = 0; i < DP_N_QUEUES; i++) skb_queue_purge(&dp->queues[i]); for (i = 0; i < DP_MAX_GROUPS; i++) kfree(dp->groups[i]); free_percpu(dp->stats_percpu); kobject_put(&dp->ifobj); module_put(THIS_MODULE); } static int destroy_dp(int dp_idx) { struct datapath *dp; int err; rtnl_lock(); mutex_lock(&dp_mutex); dp = get_dp(dp_idx); err = -ENODEV; if (!dp) goto err_unlock; do_destroy_dp(dp); err = 0; err_unlock: mutex_unlock(&dp_mutex); rtnl_unlock(); return err; } static void release_nbp(struct kobject *kobj) { struct net_bridge_port *p = container_of(kobj, struct net_bridge_port, kobj); kfree(p); } struct kobj_type brport_ktype = { #ifdef CONFIG_SYSFS .sysfs_ops = &brport_sysfs_ops, #endif .release = release_nbp }; /* Called with RTNL lock and dp_mutex. */ static int new_nbp(struct datapath *dp, struct net_device *dev, int port_no) { struct net_bridge_port *p; if (dev->br_port != NULL) return -EBUSY; p = kzalloc(sizeof(*p), GFP_KERNEL); if (!p) return -ENOMEM; dev_set_promiscuity(dev, 1); dev_hold(dev); p->port_no = port_no; p->dp = dp; p->dev = dev; atomic_set(&p->sflow_pool, 0); if (!is_dp_dev(dev)) rcu_assign_pointer(dev->br_port, p); else { /* It would make sense to assign dev->br_port here too, but * that causes packets received on internal ports to get caught * in dp_frame_hook(). In turn dp_frame_hook() can reject them * back to network stack, but that's a waste of time. */ } rcu_assign_pointer(dp->ports[port_no], p); list_add_rcu(&p->node, &dp->port_list); dp->n_ports++; /* Initialize kobject for bridge. This will be added as * /sys/class/net//brport later, if sysfs is enabled. */ p->kobj.kset = NULL; kobject_init(&p->kobj, &brport_ktype); dp_ifinfo_notify(RTM_NEWLINK, p); return 0; } static int add_port(int dp_idx, struct odp_port __user *portp) { struct net_device *dev; struct datapath *dp; struct odp_port port; int port_no; int err; err = -EFAULT; if (copy_from_user(&port, portp, sizeof port)) goto out; port.devname[IFNAMSIZ - 1] = '\0'; rtnl_lock(); dp = get_dp_locked(dp_idx); err = -ENODEV; if (!dp) goto out_unlock_rtnl; for (port_no = 1; port_no < DP_MAX_PORTS; port_no++) if (!dp->ports[port_no]) goto got_port_no; err = -EFBIG; goto out_unlock_dp; got_port_no: if (!(port.flags & ODP_PORT_INTERNAL)) { err = -ENODEV; dev = dev_get_by_name(&init_net, port.devname); if (!dev) goto out_unlock_dp; err = -EINVAL; if (dev->flags & IFF_LOOPBACK || dev->type != ARPHRD_ETHER || is_dp_dev(dev)) goto out_put; } else { dev = dp_dev_create(dp, port.devname, port_no); err = PTR_ERR(dev); if (IS_ERR(dev)) goto out_unlock_dp; dev_hold(dev); } err = new_nbp(dp, dev, port_no); if (err) goto out_put; set_dp_devs_mtu(dp, dev); dp_sysfs_add_if(dp->ports[port_no]); err = __put_user(port_no, &port.port); out_put: dev_put(dev); out_unlock_dp: mutex_unlock(&dp->mutex); out_unlock_rtnl: rtnl_unlock(); out: return err; } int dp_del_port(struct net_bridge_port *p) { ASSERT_RTNL(); if (p->port_no != ODPP_LOCAL) dp_sysfs_del_if(p); dp_ifinfo_notify(RTM_DELLINK, p); p->dp->n_ports--; if (is_dp_dev(p->dev)) { /* Make sure that no packets arrive from now on, since * dp_dev_xmit() will try to find itself through * p->dp->ports[], and we're about to set that to null. */ netif_tx_disable(p->dev); } /* First drop references to device. */ dev_set_promiscuity(p->dev, -1); list_del_rcu(&p->node); rcu_assign_pointer(p->dp->ports[p->port_no], NULL); rcu_assign_pointer(p->dev->br_port, NULL); /* Then wait until no one is still using it, and destroy it. */ synchronize_rcu(); if (is_dp_dev(p->dev)) dp_dev_destroy(p->dev); dev_put(p->dev); kobject_put(&p->kobj); return 0; } static int del_port(int dp_idx, int port_no) { struct net_bridge_port *p; struct datapath *dp; LIST_HEAD(dp_devs); int err; err = -EINVAL; if (port_no < 0 || port_no >= DP_MAX_PORTS || port_no == ODPP_LOCAL) goto out; rtnl_lock(); dp = get_dp_locked(dp_idx); err = -ENODEV; if (!dp) goto out_unlock_rtnl; p = dp->ports[port_no]; err = -ENOENT; if (!p) goto out_unlock_dp; err = dp_del_port(p); out_unlock_dp: mutex_unlock(&dp->mutex); out_unlock_rtnl: rtnl_unlock(); out: return err; } /* Must be called with rcu_read_lock. */ static void do_port_input(struct net_bridge_port *p, struct sk_buff *skb) { /* Make our own copy of the packet. Otherwise we will mangle the * packet for anyone who came before us (e.g. tcpdump via AF_PACKET). * (No one comes after us, since we tell handle_bridge() that we took * the packet.) */ skb = skb_share_check(skb, GFP_ATOMIC); if (!skb) return; /* Push the Ethernet header back on. */ skb_push(skb, ETH_HLEN); skb_reset_mac_header(skb); dp_process_received_packet(skb, p); } /* Must be called with rcu_read_lock and with bottom-halves disabled. */ void dp_process_received_packet(struct sk_buff *skb, struct net_bridge_port *p) { struct datapath *dp = p->dp; struct dp_stats_percpu *stats; struct odp_flow_key key; struct sw_flow *flow; WARN_ON_ONCE(skb_shared(skb)); /* BHs are off so we don't have to use get_cpu()/put_cpu() here. */ stats = percpu_ptr(dp->stats_percpu, smp_processor_id()); if (flow_extract(skb, p ? p->port_no : ODPP_NONE, &key)) { if (dp->drop_frags) { kfree_skb(skb); stats->n_frags++; return; } } flow = dp_table_lookup(rcu_dereference(dp->table), &key); if (flow) { struct sw_flow_actions *acts = rcu_dereference(flow->sf_acts); flow_used(flow, skb); execute_actions(dp, skb, &key, acts->actions, acts->n_actions, GFP_ATOMIC); stats->n_hit++; } else { stats->n_missed++; dp_output_control(dp, skb, _ODPL_MISS_NR, 0); } } /* * Used as br_handle_frame_hook. (Cannot run bridge at the same time, even on * different set of devices!) */ #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22) /* Called with rcu_read_lock and bottom-halves disabled. */ static struct sk_buff *dp_frame_hook(struct net_bridge_port *p, struct sk_buff *skb) { do_port_input(p, skb); return NULL; } #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0) /* Called with rcu_read_lock and bottom-halves disabled. */ static int dp_frame_hook(struct net_bridge_port *p, struct sk_buff **pskb) { do_port_input(p, *pskb); return 1; } #else #error #endif #if defined(CONFIG_XEN) && defined(HAVE_PROTO_DATA_VALID) /* This code is based on a skb_checksum_setup from net/dev/core.c from a * combination of Lenny's 2.6.26 Xen kernel and Xen's * linux-2.6.18-92.1.10.el5.xs5.0.0.394.644. We can't call this function * directly because it isn't exported in all versions. */ static int skb_pull_up_to(struct sk_buff *skb, void *ptr) { if (ptr < (void *)skb->tail) return 1; if (__pskb_pull_tail(skb, ptr - (void *)skb->data - skb_headlen(skb))) { return 1; } else { return 0; } } 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 (!skb_pull_up_to(skb, skb_network_header(skb) + 1)) 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()) printk(KERN_ERR "Attempting to checksum a non-" "TCP/UDP packet, dropping a protocol" " %d packet", iph->protocol); goto out; } if (!skb_pull_up_to(skb, th + csum_offset + 2)) goto out; skb->ip_summed = CHECKSUM_PARTIAL; skb->proto_csum_blank = 0; #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 err = 0; out: return err; } #endif /* CONFIG_XEN && HAVE_PROTO_DATA_VALID */ /* 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. * 2. CHECKSUM_COMPLETE (CHECKSUM_HW): Good device that computes checksums, * also the GRE module. This is the same as CHECKSUM_NONE, except it has * a valid skb->csum. Importantly, both contain a full checksum (not * verified) in the packet itself. The only difference is that if the * packet gets to L4 processing on this machine (not in DomU) we won't * have to recompute the checksum to verify. Most hardware devices do not * produce packets with this type, even if they support receive checksum * offloading (they produce type #5). * 3. CHECKSUM_PARTIAL (CHECKSUM_HW): Packet without full checksum and needs to * be computed if it is sent off box. Unfortunately on earlier kernels, * this case is impossible to distinguish from #2, despite having opposite * meanings. Xen adds an extra field on earlier kernels (see #4) in order * to distinguish the different states. The only real user of this type * with bridging is Xen (on later kernels). * 4. CHECKSUM_UNNECESSARY (with proto_csum_blank true): This packet was * generated locally by a Xen DomU and has a partial checksum. If it is * handled on this machine (Dom0 or DomU), then the checksum will not be * computed. If it goes off box, the checksum in the packet needs to * completed. Calling skb_checksum_setup converts this to CHECKSUM_HW * (CHECKSUM_PARTIAL) so that the checksum can be completed. In later * kernels, this combination is replaced with CHECKSUM_PARTIAL. * 5. CHECKSUM_UNNECESSARY (with proto_csum_blank false): Packet with a correct * full checksum or using a protocol without a checksum. skb->csum is * undefined. This is common from devices with receive checksum * offloading. This is somewhat similar to CHECKSUM_NONE, except that * nobody will try to verify the checksum with CHECKSUM_UNNECESSARY. * * Note that on earlier kernels, CHECKSUM_COMPLETE and CHECKSUM_PARTIAL are * both defined as CHECKSUM_HW. Normally the meaning of CHECKSUM_HW is clear * based on whether it is on the transmit or receive path. After the datapath * it will be intepreted as CHECKSUM_PARTIAL. If the packet already has a * checksum, we will panic. Since we can receive packets with checksums, we * assume that all CHECKSUM_HW packets have checksums and map them to * CHECKSUM_NONE, which has a similar meaning (the it is only different if the * packet is processed by the local IP stack, in which case it will need to * be reverified). If we receive a packet with CHECKSUM_HW that really means * CHECKSUM_PARTIAL, it will be sent with the wrong checksum. However, there * shouldn't be any devices that do this with bridging. * * The bridge has similar behavior and this function closely resembles * skb_forward_csum(). 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.*/ void forward_ip_summed(struct sk_buff *skb) { #ifdef CHECKSUM_HW if (skb->ip_summed == CHECKSUM_HW) skb->ip_summed = CHECKSUM_NONE; #endif } /* Append each packet in 'skb' list to 'queue'. There will be only one packet * unless we broke up a GSO packet. */ static int queue_control_packets(struct sk_buff *skb, struct sk_buff_head *queue, int queue_no, u32 arg) { struct sk_buff *nskb; int port_no; int err; port_no = ODPP_LOCAL; if (skb->dev) { if (skb->dev->br_port) port_no = skb->dev->br_port->port_no; else if (is_dp_dev(skb->dev)) port_no = dp_dev_priv(skb->dev)->port_no; } do { struct odp_msg *header; nskb = skb->next; skb->next = NULL; /* If a checksum-deferred packet is forwarded to the * controller, correct the pointers and checksum. This happens * on a regular basis only on Xen, on which VMs can pass up * packets that do not have their checksum computed. */ err = vswitch_skb_checksum_setup(skb); if (err) goto err_kfree_skbs; #ifndef CHECKSUM_HW if (skb->ip_summed == CHECKSUM_PARTIAL) { #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22) /* Until 2.6.22, the start of the transport header was * also the start of data to be checksummed. Linux * 2.6.22 introduced the csum_start field for this * purpose, but we should point the transport header to * it anyway for backward compatibility, as * dev_queue_xmit() does even in 2.6.28. */ skb_set_transport_header(skb, skb->csum_start - skb_headroom(skb)); #endif err = skb_checksum_help(skb); if (err) goto err_kfree_skbs; } #else if (skb->ip_summed == CHECKSUM_HW) { err = skb_checksum_help(skb, 0); if (err) goto err_kfree_skbs; } #endif err = skb_cow(skb, sizeof *header); if (err) goto err_kfree_skbs; header = (struct odp_msg*)__skb_push(skb, sizeof *header); header->type = queue_no; header->length = skb->len; header->port = port_no; header->reserved = 0; header->arg = arg; skb_queue_tail(queue, skb); skb = nskb; } while (skb); return 0; err_kfree_skbs: kfree_skb(skb); while ((skb = nskb) != NULL) { nskb = skb->next; kfree_skb(skb); } return err; } int dp_output_control(struct datapath *dp, struct sk_buff *skb, int queue_no, u32 arg) { struct dp_stats_percpu *stats; struct sk_buff_head *queue; int err; WARN_ON_ONCE(skb_shared(skb)); BUG_ON(queue_no != _ODPL_MISS_NR && queue_no != _ODPL_ACTION_NR && queue_no != _ODPL_SFLOW_NR); queue = &dp->queues[queue_no]; err = -ENOBUFS; if (skb_queue_len(queue) >= DP_MAX_QUEUE_LEN) goto err_kfree_skb; forward_ip_summed(skb); /* Break apart GSO packets into their component pieces. Otherwise * userspace may try to stuff a 64kB packet into a 1500-byte MTU. */ if (skb_is_gso(skb)) { struct sk_buff *nskb = skb_gso_segment(skb, 0); if (nskb) { kfree_skb(skb); skb = nskb; if (unlikely(IS_ERR(skb))) { err = PTR_ERR(skb); goto err; } } else { /* XXX This case might not be possible. It's hard to * tell from the skb_gso_segment() code and comment. */ } } err = queue_control_packets(skb, queue, queue_no, arg); wake_up_interruptible(&dp->waitqueue); return err; err_kfree_skb: kfree_skb(skb); err: stats = percpu_ptr(dp->stats_percpu, get_cpu()); stats->n_lost++; put_cpu(); return err; } static int flush_flows(struct datapath *dp) { dp->n_flows = 0; return dp_table_flush(dp); } static int validate_actions(const struct sw_flow_actions *actions) { unsigned int i; for (i = 0; i < actions->n_actions; i++) { const union odp_action *a = &actions->actions[i]; switch (a->type) { case ODPAT_OUTPUT: if (a->output.port >= DP_MAX_PORTS) return -EINVAL; break; case ODPAT_OUTPUT_GROUP: if (a->output_group.group >= DP_MAX_GROUPS) return -EINVAL; break; case ODPAT_SET_VLAN_VID: if (a->vlan_vid.vlan_vid & htons(~VLAN_VID_MASK)) return -EINVAL; break; case ODPAT_SET_VLAN_PCP: if (a->vlan_pcp.vlan_pcp & ~(VLAN_PCP_MASK >> VLAN_PCP_SHIFT)) return -EINVAL; break; default: if (a->type >= ODPAT_N_ACTIONS) return -EOPNOTSUPP; break; } } return 0; } static struct sw_flow_actions *get_actions(const struct odp_flow *flow) { struct sw_flow_actions *actions; int error; actions = flow_actions_alloc(flow->n_actions); error = PTR_ERR(actions); if (IS_ERR(actions)) goto error; error = -EFAULT; if (copy_from_user(actions->actions, flow->actions, flow->n_actions * sizeof(union odp_action))) goto error_free_actions; error = validate_actions(actions); if (error) goto error_free_actions; return actions; error_free_actions: kfree(actions); error: return ERR_PTR(error); } static void get_stats(struct sw_flow *flow, struct odp_flow_stats *stats) { if (flow->used.tv_sec) { stats->used_sec = flow->used.tv_sec; stats->used_nsec = flow->used.tv_nsec; } else { stats->used_sec = 0; stats->used_nsec = 0; } stats->n_packets = flow->packet_count; stats->n_bytes = flow->byte_count; stats->ip_tos = flow->ip_tos; stats->tcp_flags = flow->tcp_flags; stats->error = 0; } static void clear_stats(struct sw_flow *flow) { flow->used.tv_sec = flow->used.tv_nsec = 0; flow->tcp_flags = 0; flow->ip_tos = 0; flow->packet_count = 0; flow->byte_count = 0; } static int put_flow(struct datapath *dp, struct odp_flow_put __user *ufp) { struct odp_flow_put uf; struct sw_flow *flow; struct dp_table *table; struct odp_flow_stats stats; int error; error = -EFAULT; if (copy_from_user(&uf, ufp, sizeof(struct odp_flow_put))) goto error; uf.flow.key.reserved = 0; table = rcu_dereference(dp->table); flow = dp_table_lookup(table, &uf.flow.key); if (!flow) { /* No such flow. */ struct sw_flow_actions *acts; error = -ENOENT; if (!(uf.flags & ODPPF_CREATE)) goto error; /* Expand table, if necessary, to make room. */ if (dp->n_flows >= table->n_buckets) { error = -ENOSPC; if (table->n_buckets >= DP_MAX_BUCKETS) goto error; error = dp_table_expand(dp); if (error) goto error; table = rcu_dereference(dp->table); } /* Allocate flow. */ error = -ENOMEM; flow = kmem_cache_alloc(flow_cache, GFP_KERNEL); if (flow == NULL) goto error; flow->key = uf.flow.key; spin_lock_init(&flow->lock); clear_stats(flow); /* Obtain actions. */ acts = get_actions(&uf.flow); error = PTR_ERR(acts); if (IS_ERR(acts)) goto error_free_flow; rcu_assign_pointer(flow->sf_acts, acts); /* Put flow in bucket. */ error = dp_table_insert(table, flow); if (error) goto error_free_flow_acts; dp->n_flows++; memset(&stats, 0, sizeof(struct odp_flow_stats)); } else { /* We found a matching flow. */ struct sw_flow_actions *old_acts, *new_acts; unsigned long int flags; /* Bail out if we're not allowed to modify an existing flow. */ error = -EEXIST; if (!(uf.flags & ODPPF_MODIFY)) goto error; /* Swap actions. */ new_acts = get_actions(&uf.flow); error = PTR_ERR(new_acts); if (IS_ERR(new_acts)) goto error; old_acts = rcu_dereference(flow->sf_acts); if (old_acts->n_actions != new_acts->n_actions || memcmp(old_acts->actions, new_acts->actions, sizeof(union odp_action) * old_acts->n_actions)) { rcu_assign_pointer(flow->sf_acts, new_acts); flow_deferred_free_acts(old_acts); } else { kfree(new_acts); } /* Fetch stats, then clear them if necessary. */ spin_lock_irqsave(&flow->lock, flags); get_stats(flow, &stats); if (uf.flags & ODPPF_ZERO_STATS) clear_stats(flow); spin_unlock_irqrestore(&flow->lock, flags); } /* Copy stats to userspace. */ if (__copy_to_user(&ufp->flow.stats, &stats, sizeof(struct odp_flow_stats))) return -EFAULT; return 0; error_free_flow_acts: kfree(flow->sf_acts); error_free_flow: kmem_cache_free(flow_cache, flow); error: return error; } static int put_actions(const struct sw_flow *flow, struct odp_flow __user *ufp) { union odp_action __user *actions; struct sw_flow_actions *sf_acts; u32 n_actions; if (__get_user(actions, &ufp->actions) || __get_user(n_actions, &ufp->n_actions)) return -EFAULT; if (!n_actions) return 0; sf_acts = rcu_dereference(flow->sf_acts); if (__put_user(sf_acts->n_actions, &ufp->n_actions) || (actions && copy_to_user(actions, sf_acts->actions, sizeof(union odp_action) * min(sf_acts->n_actions, n_actions)))) return -EFAULT; return 0; } static int answer_query(struct sw_flow *flow, u32 query_flags, struct odp_flow __user *ufp) { struct odp_flow_stats stats; unsigned long int flags; spin_lock_irqsave(&flow->lock, flags); get_stats(flow, &stats); if (query_flags & ODPFF_ZERO_TCP_FLAGS) { flow->tcp_flags = 0; } spin_unlock_irqrestore(&flow->lock, flags); if (__copy_to_user(&ufp->stats, &stats, sizeof(struct odp_flow_stats))) return -EFAULT; return put_actions(flow, ufp); } static int del_flow(struct datapath *dp, struct odp_flow __user *ufp) { struct dp_table *table = rcu_dereference(dp->table); struct odp_flow uf; struct sw_flow *flow; int error; error = -EFAULT; if (copy_from_user(&uf, ufp, sizeof uf)) goto error; uf.key.reserved = 0; flow = dp_table_lookup(table, &uf.key); error = -ENOENT; if (!flow) goto error; /* XXX redundant lookup */ error = dp_table_delete(table, flow); if (error) goto error; /* XXX These statistics might lose a few packets, since other CPUs can * be using this flow. We used to synchronize_rcu() to make sure that * we get completely accurate stats, but that blows our performance, * badly. */ dp->n_flows--; error = answer_query(flow, 0, ufp); flow_deferred_free(flow); error: return error; } static int query_flows(struct datapath *dp, const struct odp_flowvec *flowvec) { struct dp_table *table = rcu_dereference(dp->table); int i; for (i = 0; i < flowvec->n_flows; i++) { struct __user odp_flow *ufp = &flowvec->flows[i]; struct odp_flow uf; struct sw_flow *flow; int error; if (__copy_from_user(&uf, ufp, sizeof uf)) return -EFAULT; uf.key.reserved = 0; flow = dp_table_lookup(table, &uf.key); if (!flow) error = __put_user(ENOENT, &ufp->stats.error); else error = answer_query(flow, uf.flags, ufp); if (error) return -EFAULT; } return flowvec->n_flows; } struct list_flows_cbdata { struct odp_flow __user *uflows; int n_flows; int listed_flows; }; static int list_flow(struct sw_flow *flow, void *cbdata_) { struct list_flows_cbdata *cbdata = cbdata_; struct odp_flow __user *ufp = &cbdata->uflows[cbdata->listed_flows++]; int error; if (__copy_to_user(&ufp->key, &flow->key, sizeof flow->key)) return -EFAULT; error = answer_query(flow, 0, ufp); if (error) return error; if (cbdata->listed_flows >= cbdata->n_flows) return cbdata->listed_flows; return 0; } static int list_flows(struct datapath *dp, const struct odp_flowvec *flowvec) { struct list_flows_cbdata cbdata; int error; if (!flowvec->n_flows) return 0; cbdata.uflows = flowvec->flows; cbdata.n_flows = flowvec->n_flows; cbdata.listed_flows = 0; error = dp_table_foreach(rcu_dereference(dp->table), list_flow, &cbdata); return error ? error : cbdata.listed_flows; } static int do_flowvec_ioctl(struct datapath *dp, unsigned long argp, int (*function)(struct datapath *, const struct odp_flowvec *)) { struct odp_flowvec __user *uflowvec; struct odp_flowvec flowvec; int retval; uflowvec = (struct odp_flowvec __user *)argp; if (!access_ok(VERIFY_WRITE, uflowvec, sizeof *uflowvec) || copy_from_user(&flowvec, uflowvec, sizeof flowvec)) return -EFAULT; if (flowvec.n_flows > INT_MAX / sizeof(struct odp_flow)) return -EINVAL; if (!access_ok(VERIFY_WRITE, flowvec.flows, flowvec.n_flows * sizeof(struct odp_flow))) return -EFAULT; retval = function(dp, &flowvec); return (retval < 0 ? retval : retval == flowvec.n_flows ? 0 : __put_user(retval, &uflowvec->n_flows)); } static int do_execute(struct datapath *dp, const struct odp_execute *executep) { struct odp_execute execute; struct odp_flow_key key; struct sk_buff *skb; struct sw_flow_actions *actions; struct ethhdr *eth; int err; err = -EFAULT; if (copy_from_user(&execute, executep, sizeof execute)) goto error; err = -EINVAL; if (execute.length < ETH_HLEN || execute.length > 65535) goto error; err = -ENOMEM; actions = flow_actions_alloc(execute.n_actions); if (!actions) goto error; err = -EFAULT; if (copy_from_user(actions->actions, execute.actions, execute.n_actions * sizeof *execute.actions)) goto error_free_actions; err = validate_actions(actions); if (err) goto error_free_actions; err = -ENOMEM; skb = alloc_skb(execute.length, GFP_KERNEL); if (!skb) goto error_free_actions; if (execute.in_port < DP_MAX_PORTS) { struct net_bridge_port *p = dp->ports[execute.in_port]; if (p) skb->dev = p->dev; } err = -EFAULT; if (copy_from_user(skb_put(skb, execute.length), execute.data, execute.length)) goto error_free_skb; skb_reset_mac_header(skb); eth = eth_hdr(skb); /* Normally, setting the skb 'protocol' field would be handled by a * call to eth_type_trans(), but it assumes there's a sending * device, which we may not have. */ if (ntohs(eth->h_proto) >= 1536) skb->protocol = eth->h_proto; else skb->protocol = htons(ETH_P_802_2); flow_extract(skb, execute.in_port, &key); err = execute_actions(dp, skb, &key, actions->actions, actions->n_actions, GFP_KERNEL); kfree(actions); return err; error_free_skb: kfree_skb(skb); error_free_actions: kfree(actions); error: return err; } static int get_dp_stats(struct datapath *dp, struct odp_stats __user *statsp) { struct odp_stats stats; int i; stats.n_flows = dp->n_flows; stats.cur_capacity = rcu_dereference(dp->table)->n_buckets; stats.max_capacity = DP_MAX_BUCKETS; stats.n_ports = dp->n_ports; stats.max_ports = DP_MAX_PORTS; stats.max_groups = DP_MAX_GROUPS; stats.n_frags = stats.n_hit = stats.n_missed = stats.n_lost = 0; for_each_possible_cpu(i) { const struct dp_stats_percpu *s; s = percpu_ptr(dp->stats_percpu, i); stats.n_frags += s->n_frags; stats.n_hit += s->n_hit; stats.n_missed += s->n_missed; stats.n_lost += s->n_lost; } stats.max_miss_queue = DP_MAX_QUEUE_LEN; stats.max_action_queue = DP_MAX_QUEUE_LEN; return copy_to_user(statsp, &stats, sizeof stats) ? -EFAULT : 0; } /* MTU of the dp pseudo-device: ETH_DATA_LEN or the minimum of the ports */ int dp_min_mtu(const struct datapath *dp) { struct net_bridge_port *p; int mtu = 0; ASSERT_RTNL(); list_for_each_entry_rcu (p, &dp->port_list, node) { struct net_device *dev = p->dev; /* Skip any internal ports, since that's what we're trying to * set. */ if (is_dp_dev(dev)) continue; if (!mtu || dev->mtu < mtu) mtu = dev->mtu; } return mtu ? mtu : ETH_DATA_LEN; } /* Sets the MTU of all datapath devices to the minimum of the ports. 'dev' * is the device whose MTU may have changed. Must be called with RTNL lock * and dp_mutex. */ void set_dp_devs_mtu(const struct datapath *dp, struct net_device *dev) { struct net_bridge_port *p; int mtu; ASSERT_RTNL(); if (is_dp_dev(dev)) return; mtu = dp_min_mtu(dp); list_for_each_entry_rcu (p, &dp->port_list, node) { struct net_device *br_dev = p->dev; if (is_dp_dev(br_dev)) dev_set_mtu(br_dev, mtu); } } static int put_port(const struct net_bridge_port *p, struct odp_port __user *uop) { struct odp_port op; memset(&op, 0, sizeof op); strncpy(op.devname, p->dev->name, sizeof op.devname); op.port = p->port_no; op.flags = is_dp_dev(p->dev) ? ODP_PORT_INTERNAL : 0; return copy_to_user(uop, &op, sizeof op) ? -EFAULT : 0; } static int query_port(struct datapath *dp, struct odp_port __user *uport) { struct odp_port port; if (copy_from_user(&port, uport, sizeof port)) return -EFAULT; if (port.devname[0]) { struct net_bridge_port *p; struct net_device *dev; int err; port.devname[IFNAMSIZ - 1] = '\0'; dev = dev_get_by_name(&init_net, port.devname); if (!dev) return -ENODEV; p = dev->br_port; if (!p && is_dp_dev(dev)) { struct dp_dev *dp_dev = dp_dev_priv(dev); if (dp_dev->dp == dp) p = dp->ports[dp_dev->port_no]; } err = p && p->dp == dp ? put_port(p, uport) : -ENOENT; dev_put(dev); return err; } else { if (port.port >= DP_MAX_PORTS) return -EINVAL; if (!dp->ports[port.port]) return -ENOENT; return put_port(dp->ports[port.port], uport); } } static int list_ports(struct datapath *dp, struct odp_portvec __user *pvp) { struct odp_portvec pv; struct net_bridge_port *p; int idx; if (copy_from_user(&pv, pvp, sizeof pv)) return -EFAULT; idx = 0; if (pv.n_ports) { list_for_each_entry_rcu (p, &dp->port_list, node) { if (put_port(p, &pv.ports[idx])) return -EFAULT; if (idx++ >= pv.n_ports) break; } } return put_user(dp->n_ports, &pvp->n_ports); } /* RCU callback for freeing a dp_port_group */ static void free_port_group(struct rcu_head *rcu) { struct dp_port_group *g = container_of(rcu, struct dp_port_group, rcu); kfree(g); } static int set_port_group(struct datapath *dp, const struct odp_port_group __user *upg) { struct odp_port_group pg; struct dp_port_group *new_group, *old_group; int error; error = -EFAULT; if (copy_from_user(&pg, upg, sizeof pg)) goto error; error = -EINVAL; if (pg.n_ports > DP_MAX_PORTS || pg.group >= DP_MAX_GROUPS) goto error; error = -ENOMEM; new_group = kmalloc(sizeof *new_group + sizeof(u16) * pg.n_ports, GFP_KERNEL); if (!new_group) goto error; new_group->n_ports = pg.n_ports; error = -EFAULT; if (copy_from_user(new_group->ports, pg.ports, sizeof(u16) * pg.n_ports)) goto error_free; old_group = rcu_dereference(dp->groups[pg.group]); rcu_assign_pointer(dp->groups[pg.group], new_group); if (old_group) call_rcu(&old_group->rcu, free_port_group); return 0; error_free: kfree(new_group); error: return error; } static int get_port_group(struct datapath *dp, struct odp_port_group *upg) { struct odp_port_group pg; struct dp_port_group *g; u16 n_copy; if (copy_from_user(&pg, upg, sizeof pg)) return -EFAULT; if (pg.group >= DP_MAX_GROUPS) return -EINVAL; g = dp->groups[pg.group]; n_copy = g ? min_t(int, g->n_ports, pg.n_ports) : 0; if (n_copy && copy_to_user(pg.ports, g->ports, n_copy * sizeof(u16))) return -EFAULT; if (put_user(g ? g->n_ports : 0, &upg->n_ports)) return -EFAULT; return 0; } static int get_listen_mask(const struct file *f) { return (long)f->private_data; } static void set_listen_mask(struct file *f, int listen_mask) { f->private_data = (void*)(long)listen_mask; } static long openvswitch_ioctl(struct file *f, unsigned int cmd, unsigned long argp) { int dp_idx = iminor(f->f_dentry->d_inode); struct datapath *dp; int drop_frags, listeners, port_no; unsigned int sflow_probability; int err; /* Handle commands with special locking requirements up front. */ switch (cmd) { case ODP_DP_CREATE: err = create_dp(dp_idx, (char __user *)argp); goto exit; case ODP_DP_DESTROY: err = destroy_dp(dp_idx); goto exit; case ODP_PORT_ADD: err = add_port(dp_idx, (struct odp_port __user *)argp); goto exit; case ODP_PORT_DEL: err = get_user(port_no, (int __user *)argp); if (!err) err = del_port(dp_idx, port_no); goto exit; } dp = get_dp_locked(dp_idx); err = -ENODEV; if (!dp) goto exit; switch (cmd) { case ODP_DP_STATS: err = get_dp_stats(dp, (struct odp_stats __user *)argp); break; case ODP_GET_DROP_FRAGS: err = put_user(dp->drop_frags, (int __user *)argp); break; case ODP_SET_DROP_FRAGS: err = get_user(drop_frags, (int __user *)argp); if (err) break; err = -EINVAL; if (drop_frags != 0 && drop_frags != 1) break; dp->drop_frags = drop_frags; err = 0; break; case ODP_GET_LISTEN_MASK: err = put_user(get_listen_mask(f), (int __user *)argp); break; case ODP_SET_LISTEN_MASK: err = get_user(listeners, (int __user *)argp); if (err) break; err = -EINVAL; if (listeners & ~ODPL_ALL) break; err = 0; set_listen_mask(f, listeners); break; case ODP_GET_SFLOW_PROBABILITY: err = put_user(dp->sflow_probability, (unsigned int __user *)argp); break; case ODP_SET_SFLOW_PROBABILITY: err = get_user(sflow_probability, (unsigned int __user *)argp); if (!err) dp->sflow_probability = sflow_probability; break; case ODP_PORT_QUERY: err = query_port(dp, (struct odp_port __user *)argp); break; case ODP_PORT_LIST: err = list_ports(dp, (struct odp_portvec __user *)argp); break; case ODP_PORT_GROUP_SET: err = set_port_group(dp, (struct odp_port_group __user *)argp); break; case ODP_PORT_GROUP_GET: err = get_port_group(dp, (struct odp_port_group __user *)argp); break; case ODP_FLOW_FLUSH: err = flush_flows(dp); break; case ODP_FLOW_PUT: err = put_flow(dp, (struct odp_flow_put __user *)argp); break; case ODP_FLOW_DEL: err = del_flow(dp, (struct odp_flow __user *)argp); break; case ODP_FLOW_GET: err = do_flowvec_ioctl(dp, argp, query_flows); break; case ODP_FLOW_LIST: err = do_flowvec_ioctl(dp, argp, list_flows); break; case ODP_EXECUTE: err = do_execute(dp, (struct odp_execute __user *)argp); break; default: err = -ENOIOCTLCMD; break; } mutex_unlock(&dp->mutex); exit: return err; } static int dp_has_packet_of_interest(struct datapath *dp, int listeners) { int i; for (i = 0; i < DP_N_QUEUES; i++) { if (listeners & (1 << i) && !skb_queue_empty(&dp->queues[i])) return 1; } return 0; } ssize_t openvswitch_read(struct file *f, char __user *buf, size_t nbytes, loff_t *ppos) { /* XXX is there sufficient synchronization here? */ int listeners = get_listen_mask(f); int dp_idx = iminor(f->f_dentry->d_inode); struct datapath *dp = get_dp(dp_idx); struct sk_buff *skb; struct iovec __user iov; size_t copy_bytes; int retval; if (!dp) return -ENODEV; if (nbytes == 0 || !listeners) return 0; for (;;) { int i; for (i = 0; i < DP_N_QUEUES; i++) { if (listeners & (1 << i)) { skb = skb_dequeue(&dp->queues[i]); if (skb) goto success; } } if (f->f_flags & O_NONBLOCK) { retval = -EAGAIN; goto error; } wait_event_interruptible(dp->waitqueue, dp_has_packet_of_interest(dp, listeners)); if (signal_pending(current)) { retval = -ERESTARTSYS; goto error; } } success: copy_bytes = min_t(size_t, skb->len, nbytes); iov.iov_base = buf; iov.iov_len = copy_bytes; retval = skb_copy_datagram_iovec(skb, 0, &iov, iov.iov_len); if (!retval) retval = copy_bytes; kfree_skb(skb); error: return retval; } static unsigned int openvswitch_poll(struct file *file, poll_table *wait) { /* XXX is there sufficient synchronization here? */ int dp_idx = iminor(file->f_dentry->d_inode); struct datapath *dp = get_dp(dp_idx); unsigned int mask; if (dp) { mask = 0; poll_wait(file, &dp->waitqueue, wait); if (dp_has_packet_of_interest(dp, get_listen_mask(file))) mask |= POLLIN | POLLRDNORM; } else { mask = POLLIN | POLLRDNORM | POLLHUP; } return mask; } struct file_operations openvswitch_fops = { /* XXX .aio_read = openvswitch_aio_read, */ .read = openvswitch_read, .poll = openvswitch_poll, .unlocked_ioctl = openvswitch_ioctl, /* XXX .fasync = openvswitch_fasync, */ }; static int major; #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,27) static struct llc_sap *dp_stp_sap; static int dp_stp_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { /* We don't really care about STP packets, we just listen for them for * mutual exclusion with the bridge module, so this just discards * them. */ kfree_skb(skb); return 0; } static int dp_avoid_bridge_init(void) { /* Register to receive STP packets because the bridge module also * attempts to do so. Since there can only be a single listener for a * given protocol, this provides mutual exclusion against the bridge * module, preventing both of them from being loaded at the same * time. */ dp_stp_sap = llc_sap_open(LLC_SAP_BSPAN, dp_stp_rcv); if (!dp_stp_sap) { printk(KERN_ERR "openvswitch: can't register sap for STP (probably the bridge module is loaded)\n"); return -EADDRINUSE; } return 0; } static void dp_avoid_bridge_exit(void) { llc_sap_put(dp_stp_sap); } #else /* Linux 2.6.27 or later. */ static int dp_avoid_bridge_init(void) { /* Linux 2.6.27 introduces a way for multiple clients to register for * STP packets, which interferes with what we try to do above. * Instead, just check whether there's a bridge hook defined. This is * not as safe--the bridge module is willing to load over the top of * us--but it provides a little bit of protection. */ if (br_handle_frame_hook) { printk(KERN_ERR "openvswitch: bridge module is loaded, cannot load over it\n"); return -EADDRINUSE; } return 0; } static void dp_avoid_bridge_exit(void) { /* Nothing to do. */ } #endif /* Linux 2.6.27 or later */ static int __init dp_init(void) { int err; printk("Open vSwitch %s, built "__DATE__" "__TIME__"\n", VERSION BUILDNR); err = dp_avoid_bridge_init(); if (err) return err; err = flow_init(); if (err) goto error; err = register_netdevice_notifier(&dp_device_notifier); if (err) goto error_flow_exit; major = register_chrdev(0, "openvswitch", &openvswitch_fops); if (err < 0) goto error_unreg_notifier; /* Hook into callback used by the bridge to intercept packets. * Parasites we are. */ br_handle_frame_hook = dp_frame_hook; return 0; error_unreg_notifier: unregister_netdevice_notifier(&dp_device_notifier); error_flow_exit: flow_exit(); error: return err; } static void dp_cleanup(void) { rcu_barrier(); unregister_chrdev(major, "openvswitch"); unregister_netdevice_notifier(&dp_device_notifier); flow_exit(); br_handle_frame_hook = NULL; dp_avoid_bridge_exit(); } module_init(dp_init); module_exit(dp_cleanup); MODULE_DESCRIPTION("Open vSwitch switching datapath"); MODULE_LICENSE("GPL");