diff options
Diffstat (limited to 'datapath/datapath.c')
| -rw-r--r-- | datapath/datapath.c | 1611 |
1 files changed, 1611 insertions, 0 deletions
diff --git a/datapath/datapath.c b/datapath/datapath.c new file mode 100644 index 000000000..015edc4bb --- /dev/null +++ b/datapath/datapath.c @@ -0,0 +1,1611 @@ +/* + * Distributed under the terms of the GNU GPL version 2. + * Copyright (c) 2007, 2008, 2009 Nicira Networks. + */ + +/* Functions for managing the dp interface/device. */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/if_arp.h> +#include <linux/if_bridge.h> +#include <linux/if_vlan.h> +#include <linux/in.h> +#include <linux/ip.h> +#include <linux/delay.h> +#include <linux/time.h> +#include <linux/etherdevice.h> +#include <linux/kernel.h> +#include <linux/kthread.h> +#include <linux/llc.h> +#include <linux/mutex.h> +#include <linux/percpu.h> +#include <linux/rcupdate.h> +#include <linux/tcp.h> +#include <linux/udp.h> +#include <linux/version.h> +#include <linux/ethtool.h> +#include <linux/random.h> +#include <linux/wait.h> +#include <asm/system.h> +#include <asm/div64.h> +#include <asm/bug.h> +#include <linux/netfilter_bridge.h> +#include <linux/netfilter_ipv4.h> +#include <linux/inetdevice.h> +#include <linux/list.h> +#include <linux/rculist.h> +#include <linux/workqueue.h> +#include <linux/dmi.h> +#include <net/llc.h> + +#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); + +int (*dp_add_dp_hook)(struct datapath *dp); +EXPORT_SYMBOL(dp_add_dp_hook); + +int (*dp_del_dp_hook)(struct datapath *dp); +EXPORT_SYMBOL(dp_del_dp_hook); + +int (*dp_add_if_hook)(struct net_bridge_port *p); +EXPORT_SYMBOL(dp_add_if_hook); + +int (*dp_del_if_hook)(struct net_bridge_port *p); +EXPORT_SYMBOL(dp_del_if_hook); + +/* Datapaths. Protected on the read side by rcu_read_lock, on the write side + * by dp_mutex. dp_mutex is almost completely redundant with genl_mutex + * maintained by the Generic Netlink code, but the timeout path needs mutual + * exclusion too. + * + * 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; + } + err = rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL, GFP_KERNEL); +errout: + if (err < 0) + rtnl_set_sk_err(net, RTNLGRP_LINK, err); +} + +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; + + 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); + + /* Setup our datapath device */ + dp_dev = dp_dev_create(dp, devname, ODPP_LOCAL); + err = PTR_ERR(dp_dev); + if (IS_ERR(dp_dev)) + goto err_free_dp; + + err = -ENOMEM; + rcu_assign_pointer(dp->table, dp_table_create(DP_L1_SIZE)); + if (!dp->table) + goto err_destroy_dp_dev; + INIT_LIST_HEAD(&dp->port_list); + + err = new_nbp(dp, dp_dev, ODPP_LOCAL); + if (err) + 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(); + + if (dp_add_dp_hook) + dp_add_dp_hook(dp); + + return 0; + +err_destroy_local_port: + dp_del_port(dp->ports[ODPP_LOCAL], NULL); +err_destroy_table: + dp_table_destroy(dp->table, 0); +err_destroy_dp_dev: + dp_dev_destroy(dp_dev); +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 list_head *dp_devs) +{ + struct net_bridge_port *p, *n; + int i; + + if (dp_del_dp_hook) + dp_del_dp_hook(dp); + + /* Drop references to DP. */ + list_for_each_entry_safe (p, n, &dp->port_list, node) + dp_del_port(p, dp_devs); + + rcu_assign_pointer(dps[dp->dp_idx], NULL); + synchronize_rcu(); + + /* Wait until no longer in use, then destroy it. */ + synchronize_rcu(); + 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); + kfree(dp); + module_put(THIS_MODULE); +} + +static int destroy_dp(int dp_idx) +{ + struct dp_dev *dp_dev, *next; + struct datapath *dp; + LIST_HEAD(dp_devs); + int err; + + rtnl_lock(); + mutex_lock(&dp_mutex); + dp = get_dp(dp_idx); + err = -ENODEV; + if (!dp) + goto err_unlock; + + do_destroy_dp(dp, &dp_devs); + err = 0; + +err_unlock: + mutex_unlock(&dp_mutex); + rtnl_unlock(); + list_for_each_entry_safe (dp_dev, next, &dp_devs, list) + free_netdev(dp_dev->dev); + return err; +} + +/* 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; + 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++; + + 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'; + port_no = port.port; + + err = -EINVAL; + if (port_no < 0 || port_no >= DP_MAX_PORTS) + goto out; + + rtnl_lock(); + dp = get_dp_locked(dp_idx); + err = -ENODEV; + if (!dp) + goto out_unlock_rtnl; + + err = -EEXIST; + if (dp->ports[port_no]) + goto out_unlock_dp; + + 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; + + if (dp_add_if_hook) + dp_add_if_hook(dp->ports[port_no]); + +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, struct list_head *dp_devs) +{ + ASSERT_RTNL(); + +#ifdef SUPPORT_SYSFS + if (p->port_no != ODPP_LOCAL && dp_del_if_hook) + sysfs_remove_link(&p->dp->ifobj, p->dev->name); +#endif + 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); + if (dp_devs) { + struct dp_dev *dp_dev = dp_dev_priv(p->dev); + list_add(&dp_dev->list, dp_devs); + } + } + if (p->port_no != ODPP_LOCAL && dp_del_if_hook) { + dp_del_if_hook(p); + } else { + dev_put(p->dev); + kfree(p); + } + + return 0; +} + +static int del_port(int dp_idx, int port_no) +{ + struct dp_dev *dp_dev, *next; + 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, &dp_devs); + +out_unlock_dp: + mutex_unlock(&dp->mutex); +out_unlock_rtnl: + rtnl_unlock(); +out: + list_for_each_entry_safe (dp_dev, next, &dp_devs, list) + free_netdev(dp_dev->dev); + 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)); + WARN_ON_ONCE(skb->destructor); + + /* 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 + +#ifdef CONFIG_XEN +/* This code is copied verbatim from net/dev/core.c in Xen's + * linux-2.6.18-92.1.10.el5.xs5.0.0.394.644. We can't call those functions + * directly because they aren't exported. */ +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 skb_checksum_setup(struct sk_buff *skb) +{ + if (skb->proto_csum_blank) { + if (skb->protocol != htons(ETH_P_IP)) + goto out; + if (!skb_pull_up_to(skb, skb->nh.iph + 1)) + goto out; + skb->h.raw = (unsigned char *)skb->nh.iph + 4*skb->nh.iph->ihl; + switch (skb->nh.iph->protocol) { + case IPPROTO_TCP: + skb->csum = offsetof(struct tcphdr, check); + break; + case IPPROTO_UDP: + skb->csum = 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", skb->nh.iph->protocol); + goto out; + } + if (!skb_pull_up_to(skb, skb->h.raw + skb->csum + 2)) + goto out; + skb->ip_summed = CHECKSUM_HW; + skb->proto_csum_blank = 0; + } + return 0; +out: + return -EPROTO; +} +#endif + +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 port_no; + int err; + + WARN_ON_ONCE(skb_shared(skb)); + BUG_ON(queue_no != _ODPL_MISS_NR && queue_no != _ODPL_ACTION_NR); + + queue = &dp->queues[queue_no]; + err = -ENOBUFS; + if (skb_queue_len(queue) >= DP_MAX_QUEUE_LEN) + goto err_kfree_skb; + + /* If a checksum-deferred packet is forwarded to the controller, + * correct the pointers and checksum. This happens on a regular basis + * only on Xen (the CHECKSUM_HW case), on which VMs can pass up packets + * that do not have their checksum computed. We also implement it for + * the non-Xen case, but it is difficult to trigger or test this case + * there, hence the WARN_ON_ONCE(). + */ + err = skb_checksum_setup(skb); + if (err) + goto err_kfree_skb; +#ifndef CHECKSUM_HW + if (skb->ip_summed == CHECKSUM_PARTIAL) { + WARN_ON_ONCE(1); +#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_skb; + } +#else + if (skb->ip_summed == CHECKSUM_HW) { + err = skb_checksum_help(skb, 0); + if (err) + goto err_kfree_skb; + } +#endif + + /* 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. */ + } + } + + /* Figure out port number. */ + 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; + } + + /* Append each packet to queue. There will be only one packet unless + * we broke up a GSO packet above. */ + do { + struct odp_msg *header; + struct sk_buff *nskb = skb->next; + skb->next = NULL; + + err = skb_cow(skb, sizeof *header); + if (err) { + while (nskb) { + kfree_skb(skb); + skb = nskb; + nskb = skb->next; + } + goto err_kfree_skb; + } + + 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); + + wake_up_interruptible(&dp->waitqueue); + return 0; + +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) + 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; +} + +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, **bucket; + 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; + +retry: + table = rcu_dereference(dp->table); + bucket = dp_table_lookup_for_insert(table, &uf.flow.key); + if (!bucket) { + /* No such flow, and the slots where it could go are full. */ + error = uf.flags & ODPPF_CREATE ? -EXFULL : -ENOENT; + goto error; + } else if (!*bucket) { + /* No such flow, but we found an available slot for it. */ + 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 * 4 >= table->n_buckets && + table->n_buckets < DP_MAX_BUCKETS) { + error = dp_table_expand(dp); + if (error) + goto error; + + /* The bucket's location has changed. Try again. */ + goto retry; + } + + /* 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. */ + rcu_assign_pointer(*bucket, flow); + dp->n_flows++; + memset(&stats, 0, sizeof(struct odp_flow_stats)); + } else { + /* We found a matching flow. */ + struct sw_flow *flow = *rcu_dereference(bucket); + 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: + 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; + if (ufp->n_actions > INT_MAX / sizeof(union odp_action)) + return -EINVAL; + + 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, struct odp_flow __user *ufp) +{ + struct odp_flow_stats stats; + unsigned long int flags; + + spin_lock_irqsave(&flow->lock, flags); + get_stats(flow, &stats); + 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_or_query_flow(struct datapath *dp, + struct odp_flow __user *ufp, + unsigned int cmd) +{ + 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; + + if (cmd == ODP_FLOW_DEL) { + /* 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, ufp); + flow_deferred_free(flow); + } else { + error = answer_query(flow, ufp); + } + +error: + return error; +} + +static int query_multiple_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 = __clear_user(&ufp->stats, sizeof ufp->stats); + else + error = answer_query(flow, 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, 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; + 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; + + 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 * 2; + stats.max_capacity = DP_MAX_BUCKETS * 2; + 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; +} + +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(idx, &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 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; + int err; + + /* Handle commands with special locking requirements up front. */ + switch (cmd) { + case ODP_DP_CREATE: + return create_dp(dp_idx, (char __user *)argp); + + case ODP_DP_DESTROY: + return destroy_dp(dp_idx); + + case ODP_PORT_ADD: + return add_port(dp_idx, (struct odp_port __user *)argp); + + case ODP_PORT_DEL: + err = get_user(port_no, (int __user *)argp); + if (err) + break; + return del_port(dp_idx, port_no); + } + + dp = get_dp_locked(dp_idx); + if (!dp) + return -ENODEV; + + 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((int)f->private_data, (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; + f->private_data = (void*)listeners; + 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: + case ODP_FLOW_GET: + err = del_or_query_flow(dp, (struct odp_flow __user *)argp, + cmd); + break; + + case ODP_FLOW_GET_MULTIPLE: + err = do_flowvec_ioctl(dp, argp, query_multiple_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); + 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) +{ + int listeners = (int) f->private_data; + 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(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) +{ + 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, (int)file->private_data)) + 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; +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 __init dp_init(void) +{ + int err; + + printk("Open vSwitch %s, built "__DATE__" "__TIME__"\n", VERSION BUILDNR); + + /* 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; + } + + 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; + llc_sap_put(dp_stp_sap); +} + +module_init(dp_init); +module_exit(dp_cleanup); + +MODULE_DESCRIPTION("Open vSwitch switching datapath"); +MODULE_LICENSE("GPL"); |