diff options
Diffstat (limited to 'net/openvswitch/vport.c')
-rw-r--r-- | net/openvswitch/vport.c | 398 |
1 files changed, 398 insertions, 0 deletions
diff --git a/net/openvswitch/vport.c b/net/openvswitch/vport.c new file mode 100644 index 0000000..7f0ef37 --- /dev/null +++ b/net/openvswitch/vport.c @@ -0,0 +1,398 @@ +/* + * 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 <linux/version.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); +} |