/* * Copyright (c) 2007-2011 Nicira Networks. * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA * 02110-1301, USA */ #include <linux/dcache.h> #include <linux/etherdevice.h> #include <linux/if.h> #include <linux/if_vlan.h> #include <linux/kernel.h> #include <linux/list.h> #include <linux/mutex.h> #include <linux/percpu.h> #include <linux/rcupdate.h> #include <linux/rtnetlink.h> #include <linux/compat.h> #include "vport.h" #include "vport-internal_dev.h" /* List of statically compiled vport implementations. Don't forget to also * add yours to the list at the bottom of vport.h. */ static const struct vport_ops *vport_ops_list[] = { &ovs_netdev_vport_ops, &ovs_internal_vport_ops, }; /* Protected by RCU read lock for reading, RTNL lock for writing. */ static struct hlist_head *dev_table; #define VPORT_HASH_BUCKETS 1024 /** * ovs_vport_init - initialize vport subsystem * * Called at module load time to initialize the vport subsystem. */ int ovs_vport_init(void) { dev_table = kzalloc(VPORT_HASH_BUCKETS * sizeof(struct hlist_head), GFP_KERNEL); if (!dev_table) return -ENOMEM; return 0; } /** * ovs_vport_exit - shutdown vport subsystem * * Called at module exit time to shutdown the vport subsystem. */ void ovs_vport_exit(void) { kfree(dev_table); } static struct hlist_head *hash_bucket(const char *name) { unsigned int hash = full_name_hash(name, strlen(name)); return &dev_table[hash & (VPORT_HASH_BUCKETS - 1)]; } /** * ovs_vport_locate - find a port that has already been created * * @name: name of port to find * * Must be called with RTNL or RCU read lock. */ struct vport *ovs_vport_locate(const char *name) { struct hlist_head *bucket = hash_bucket(name); struct vport *vport; struct hlist_node *node; hlist_for_each_entry_rcu(vport, node, bucket, hash_node) if (!strcmp(name, vport->ops->get_name(vport))) return vport; return NULL; } /** * ovs_vport_alloc - allocate and initialize new vport * * @priv_size: Size of private data area to allocate. * @ops: vport device ops * * Allocate and initialize a new vport defined by @ops. The vport will contain * a private data area of size @priv_size that can be accessed using * vport_priv(). vports that are no longer needed should be released with * vport_free(). */ struct vport *ovs_vport_alloc(int priv_size, const struct vport_ops *ops, const struct vport_parms *parms) { struct vport *vport; size_t alloc_size; alloc_size = sizeof(struct vport); if (priv_size) { alloc_size = ALIGN(alloc_size, VPORT_ALIGN); alloc_size += priv_size; } vport = kzalloc(alloc_size, GFP_KERNEL); if (!vport) return ERR_PTR(-ENOMEM); vport->dp = parms->dp; vport->port_no = parms->port_no; vport->upcall_pid = parms->upcall_pid; vport->ops = ops; vport->percpu_stats = alloc_percpu(struct vport_percpu_stats); if (!vport->percpu_stats) { kfree(vport); return ERR_PTR(-ENOMEM); } spin_lock_init(&vport->stats_lock); return vport; } /** * ovs_vport_free - uninitialize and free vport * * @vport: vport to free * * Frees a vport allocated with vport_alloc() when it is no longer needed. * * The caller must ensure that an RCU grace period has passed since the last * time @vport was in a datapath. */ void ovs_vport_free(struct vport *vport) { free_percpu(vport->percpu_stats); kfree(vport); } /** * ovs_vport_add - add vport device (for kernel callers) * * @parms: Information about new vport. * * Creates a new vport with the specified configuration (which is dependent on * device type). RTNL lock must be held. */ struct vport *ovs_vport_add(const struct vport_parms *parms) { struct vport *vport; int err = 0; int i; ASSERT_RTNL(); for (i = 0; i < ARRAY_SIZE(vport_ops_list); i++) { if (vport_ops_list[i]->type == parms->type) { vport = vport_ops_list[i]->create(parms); if (IS_ERR(vport)) { err = PTR_ERR(vport); goto out; } hlist_add_head_rcu(&vport->hash_node, hash_bucket(vport->ops->get_name(vport))); return vport; } } err = -EAFNOSUPPORT; out: return ERR_PTR(err); } /** * ovs_vport_set_options - modify existing vport device (for kernel callers) * * @vport: vport to modify. * @port: New configuration. * * Modifies an existing device with the specified configuration (which is * dependent on device type). RTNL lock must be held. */ int ovs_vport_set_options(struct vport *vport, struct nlattr *options) { ASSERT_RTNL(); if (!vport->ops->set_options) return -EOPNOTSUPP; return vport->ops->set_options(vport, options); } /** * ovs_vport_del - delete existing vport device * * @vport: vport to delete. * * Detaches @vport from its datapath and destroys it. It is possible to fail * for reasons such as lack of memory. RTNL lock must be held. */ void ovs_vport_del(struct vport *vport) { ASSERT_RTNL(); hlist_del_rcu(&vport->hash_node); vport->ops->destroy(vport); } /** * ovs_vport_get_stats - retrieve device stats * * @vport: vport from which to retrieve the stats * @stats: location to store stats * * Retrieves transmit, receive, and error stats for the given device. * * Must be called with RTNL lock or rcu_read_lock. */ void ovs_vport_get_stats(struct vport *vport, struct ovs_vport_stats *stats) { int i; memset(stats, 0, sizeof(*stats)); /* We potentially have 2 sources of stats that need to be combined: * those we have collected (split into err_stats and percpu_stats) from * set_stats() and device error stats from netdev->get_stats() (for * errors that happen downstream and therefore aren't reported through * our vport_record_error() function). * Stats from first source are reported by ovs (OVS_VPORT_ATTR_STATS). * netdev-stats can be directly read over netlink-ioctl. */ spin_lock_bh(&vport->stats_lock); stats->rx_errors = vport->err_stats.rx_errors; stats->tx_errors = vport->err_stats.tx_errors; stats->tx_dropped = vport->err_stats.tx_dropped; stats->rx_dropped = vport->err_stats.rx_dropped; spin_unlock_bh(&vport->stats_lock); for_each_possible_cpu(i) { const struct vport_percpu_stats *percpu_stats; struct vport_percpu_stats local_stats; unsigned int start; percpu_stats = per_cpu_ptr(vport->percpu_stats, i); do { start = u64_stats_fetch_begin_bh(&percpu_stats->sync); local_stats = *percpu_stats; } while (u64_stats_fetch_retry_bh(&percpu_stats->sync, start)); stats->rx_bytes += local_stats.rx_bytes; stats->rx_packets += local_stats.rx_packets; stats->tx_bytes += local_stats.tx_bytes; stats->tx_packets += local_stats.tx_packets; } } /** * ovs_vport_get_options - retrieve device options * * @vport: vport from which to retrieve the options. * @skb: sk_buff where options should be appended. * * Retrieves the configuration of the given device, appending an * %OVS_VPORT_ATTR_OPTIONS attribute that in turn contains nested * vport-specific attributes to @skb. * * Returns 0 if successful, -EMSGSIZE if @skb has insufficient room, or another * negative error code if a real error occurred. If an error occurs, @skb is * left unmodified. * * Must be called with RTNL lock or rcu_read_lock. */ int ovs_vport_get_options(const struct vport *vport, struct sk_buff *skb) { struct nlattr *nla; nla = nla_nest_start(skb, OVS_VPORT_ATTR_OPTIONS); if (!nla) return -EMSGSIZE; if (vport->ops->get_options) { int err = vport->ops->get_options(vport, skb); if (err) { nla_nest_cancel(skb, nla); return err; } } nla_nest_end(skb, nla); return 0; } /** * ovs_vport_receive - pass up received packet to the datapath for processing * * @vport: vport that received the packet * @skb: skb that was received * * Must be called with rcu_read_lock. The packet cannot be shared and * skb->data should point to the Ethernet header. The caller must have already * called compute_ip_summed() to initialize the checksumming fields. */ void ovs_vport_receive(struct vport *vport, struct sk_buff *skb) { struct vport_percpu_stats *stats; stats = per_cpu_ptr(vport->percpu_stats, smp_processor_id()); u64_stats_update_begin(&stats->sync); stats->rx_packets++; stats->rx_bytes += skb->len; u64_stats_update_end(&stats->sync); ovs_dp_process_received_packet(vport, skb); } /** * ovs_vport_send - send a packet on a device * * @vport: vport on which to send the packet * @skb: skb to send * * Sends the given packet and returns the length of data sent. Either RTNL * lock or rcu_read_lock must be held. */ int ovs_vport_send(struct vport *vport, struct sk_buff *skb) { int sent = vport->ops->send(vport, skb); if (likely(sent)) { struct vport_percpu_stats *stats; stats = per_cpu_ptr(vport->percpu_stats, smp_processor_id()); u64_stats_update_begin(&stats->sync); stats->tx_packets++; stats->tx_bytes += sent; u64_stats_update_end(&stats->sync); } return sent; } /** * ovs_vport_record_error - indicate device error to generic stats layer * * @vport: vport that encountered the error * @err_type: one of enum vport_err_type types to indicate the error type * * If using the vport generic stats layer indicate that an error of the given * type has occured. */ void ovs_vport_record_error(struct vport *vport, enum vport_err_type err_type) { spin_lock(&vport->stats_lock); switch (err_type) { case VPORT_E_RX_DROPPED: vport->err_stats.rx_dropped++; break; case VPORT_E_RX_ERROR: vport->err_stats.rx_errors++; break; case VPORT_E_TX_DROPPED: vport->err_stats.tx_dropped++; break; case VPORT_E_TX_ERROR: vport->err_stats.tx_errors++; break; }; spin_unlock(&vport->stats_lock); }