Linux 4.1.16

[linux/fpc-iii.git] / net / switchdev / switchdev.c

/*
 * net/switchdev/switchdev.c - Switch device API
 * Copyright (c) 2014 Jiri Pirko <jiri@resnulli.us>
 * Copyright (c) 2014-2015 Scott Feldman <sfeldma@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/notifier.h>
#include <linux/netdevice.h>
#include <net/ip_fib.h>
#include <net/switchdev.h>

/**
 *      netdev_switch_parent_id_get - Get ID of a switch
 *      @dev: port device
 *      @psid: switch ID
 *
 *      Get ID of a switch this port is part of.
 */
int netdev_switch_parent_id_get(struct net_device *dev,
                                struct netdev_phys_item_id *psid)
{
        const struct swdev_ops *ops = dev->swdev_ops;

        if (!ops || !ops->swdev_parent_id_get)
                return -EOPNOTSUPP;
        return ops->swdev_parent_id_get(dev, psid);
}
EXPORT_SYMBOL_GPL(netdev_switch_parent_id_get);

/**
 *      netdev_switch_port_stp_update - Notify switch device port of STP
 *                                      state change
 *      @dev: port device
 *      @state: port STP state
 *
 *      Notify switch device port of bridge port STP state change.
 */
int netdev_switch_port_stp_update(struct net_device *dev, u8 state)
{
        const struct swdev_ops *ops = dev->swdev_ops;
        struct net_device *lower_dev;
        struct list_head *iter;
        int err = -EOPNOTSUPP;

        if (ops && ops->swdev_port_stp_update)
                return ops->swdev_port_stp_update(dev, state);

        netdev_for_each_lower_dev(dev, lower_dev, iter) {
                err = netdev_switch_port_stp_update(lower_dev, state);
                if (err && err != -EOPNOTSUPP)
                        return err;
        }

        return err;
}
EXPORT_SYMBOL_GPL(netdev_switch_port_stp_update);

static DEFINE_MUTEX(netdev_switch_mutex);
static RAW_NOTIFIER_HEAD(netdev_switch_notif_chain);

/**
 *      register_netdev_switch_notifier - Register notifier
 *      @nb: notifier_block
 *
 *      Register switch device notifier. This should be used by code
 *      which needs to monitor events happening in particular device.
 *      Return values are same as for atomic_notifier_chain_register().
 */
int register_netdev_switch_notifier(struct notifier_block *nb)
{
        int err;

        mutex_lock(&netdev_switch_mutex);
        err = raw_notifier_chain_register(&netdev_switch_notif_chain, nb);
        mutex_unlock(&netdev_switch_mutex);
        return err;
}
EXPORT_SYMBOL_GPL(register_netdev_switch_notifier);

/**
 *      unregister_netdev_switch_notifier - Unregister notifier
 *      @nb: notifier_block
 *
 *      Unregister switch device notifier.
 *      Return values are same as for atomic_notifier_chain_unregister().
 */
int unregister_netdev_switch_notifier(struct notifier_block *nb)
{
        int err;

        mutex_lock(&netdev_switch_mutex);
        err = raw_notifier_chain_unregister(&netdev_switch_notif_chain, nb);
        mutex_unlock(&netdev_switch_mutex);
        return err;
}
EXPORT_SYMBOL_GPL(unregister_netdev_switch_notifier);

/**
 *      call_netdev_switch_notifiers - Call notifiers
 *      @val: value passed unmodified to notifier function
 *      @dev: port device
 *      @info: notifier information data
 *
 *      Call all network notifier blocks. This should be called by driver
 *      when it needs to propagate hardware event.
 *      Return values are same as for atomic_notifier_call_chain().
 */
int call_netdev_switch_notifiers(unsigned long val, struct net_device *dev,
                                 struct netdev_switch_notifier_info *info)
{
        int err;

        info->dev = dev;
        mutex_lock(&netdev_switch_mutex);
        err = raw_notifier_call_chain(&netdev_switch_notif_chain, val, info);
        mutex_unlock(&netdev_switch_mutex);
        return err;
}
EXPORT_SYMBOL_GPL(call_netdev_switch_notifiers);

/**
 *      netdev_switch_port_bridge_setlink - Notify switch device port of bridge
 *      port attributes
 *
 *      @dev: port device
 *      @nlh: netlink msg with bridge port attributes
 *      @flags: bridge setlink flags
 *
 *      Notify switch device port of bridge port attributes
 */
int netdev_switch_port_bridge_setlink(struct net_device *dev,
                                      struct nlmsghdr *nlh, u16 flags)
{
        const struct net_device_ops *ops = dev->netdev_ops;

        if (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
                return 0;

        if (!ops->ndo_bridge_setlink)
                return -EOPNOTSUPP;

        return ops->ndo_bridge_setlink(dev, nlh, flags);
}
EXPORT_SYMBOL_GPL(netdev_switch_port_bridge_setlink);

/**
 *      netdev_switch_port_bridge_dellink - Notify switch device port of bridge
 *      port attribute delete
 *
 *      @dev: port device
 *      @nlh: netlink msg with bridge port attributes
 *      @flags: bridge setlink flags
 *
 *      Notify switch device port of bridge port attribute delete
 */
int netdev_switch_port_bridge_dellink(struct net_device *dev,
                                      struct nlmsghdr *nlh, u16 flags)
{
        const struct net_device_ops *ops = dev->netdev_ops;

        if (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
                return 0;

        if (!ops->ndo_bridge_dellink)
                return -EOPNOTSUPP;

        return ops->ndo_bridge_dellink(dev, nlh, flags);
}
EXPORT_SYMBOL_GPL(netdev_switch_port_bridge_dellink);

/**
 *      ndo_dflt_netdev_switch_port_bridge_setlink - default ndo bridge setlink
 *                                                   op for master devices
 *
 *      @dev: port device
 *      @nlh: netlink msg with bridge port attributes
 *      @flags: bridge setlink flags
 *
 *      Notify master device slaves of bridge port attributes
 */
int ndo_dflt_netdev_switch_port_bridge_setlink(struct net_device *dev,
                                               struct nlmsghdr *nlh, u16 flags)
{
        struct net_device *lower_dev;
        struct list_head *iter;
        int ret = 0, err = 0;

        if (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
                return ret;

        netdev_for_each_lower_dev(dev, lower_dev, iter) {
                err = netdev_switch_port_bridge_setlink(lower_dev, nlh, flags);
                if (err && err != -EOPNOTSUPP)
                        ret = err;
        }

        return ret;
}
EXPORT_SYMBOL_GPL(ndo_dflt_netdev_switch_port_bridge_setlink);

/**
 *      ndo_dflt_netdev_switch_port_bridge_dellink - default ndo bridge dellink
 *                                                   op for master devices
 *
 *      @dev: port device
 *      @nlh: netlink msg with bridge port attributes
 *      @flags: bridge dellink flags
 *
 *      Notify master device slaves of bridge port attribute deletes
 */
int ndo_dflt_netdev_switch_port_bridge_dellink(struct net_device *dev,
                                               struct nlmsghdr *nlh, u16 flags)
{
        struct net_device *lower_dev;
        struct list_head *iter;
        int ret = 0, err = 0;

        if (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
                return ret;

        netdev_for_each_lower_dev(dev, lower_dev, iter) {
                err = netdev_switch_port_bridge_dellink(lower_dev, nlh, flags);
                if (err && err != -EOPNOTSUPP)
                        ret = err;
        }

        return ret;
}
EXPORT_SYMBOL_GPL(ndo_dflt_netdev_switch_port_bridge_dellink);

static struct net_device *netdev_switch_get_lowest_dev(struct net_device *dev)
{
        const struct swdev_ops *ops = dev->swdev_ops;
        struct net_device *lower_dev;
        struct net_device *port_dev;
        struct list_head *iter;

        /* Recusively search down until we find a sw port dev.
         * (A sw port dev supports swdev_parent_id_get).
         */

        if (dev->features & NETIF_F_HW_SWITCH_OFFLOAD &&
            ops && ops->swdev_parent_id_get)
                return dev;

        netdev_for_each_lower_dev(dev, lower_dev, iter) {
                port_dev = netdev_switch_get_lowest_dev(lower_dev);
                if (port_dev)
                        return port_dev;
        }

        return NULL;
}

static struct net_device *netdev_switch_get_dev_by_nhs(struct fib_info *fi)
{
        struct netdev_phys_item_id psid;
        struct netdev_phys_item_id prev_psid;
        struct net_device *dev = NULL;
        int nhsel;

        /* For this route, all nexthop devs must be on the same switch. */

        for (nhsel = 0; nhsel < fi->fib_nhs; nhsel++) {
                const struct fib_nh *nh = &fi->fib_nh[nhsel];

                if (!nh->nh_dev)
                        return NULL;

                dev = netdev_switch_get_lowest_dev(nh->nh_dev);
                if (!dev)
                        return NULL;

                if (netdev_switch_parent_id_get(dev, &psid))
                        return NULL;

                if (nhsel > 0) {
                        if (prev_psid.id_len != psid.id_len)
                                return NULL;
                        if (memcmp(prev_psid.id, psid.id, psid.id_len))
                                return NULL;
                }

                prev_psid = psid;
        }

        return dev;
}

/**
 *      netdev_switch_fib_ipv4_add - Add IPv4 route entry to switch
 *
 *      @dst: route's IPv4 destination address
 *      @dst_len: destination address length (prefix length)
 *      @fi: route FIB info structure
 *      @tos: route TOS
 *      @type: route type
 *      @nlflags: netlink flags passed in (NLM_F_*)
 *      @tb_id: route table ID
 *
 *      Add IPv4 route entry to switch device.
 */
int netdev_switch_fib_ipv4_add(u32 dst, int dst_len, struct fib_info *fi,
                               u8 tos, u8 type, u32 nlflags, u32 tb_id)
{
        struct net_device *dev;
        const struct swdev_ops *ops;
        int err = 0;

        /* Don't offload route if using custom ip rules or if
         * IPv4 FIB offloading has been disabled completely.
         */

#ifdef CONFIG_IP_MULTIPLE_TABLES
        if (fi->fib_net->ipv4.fib_has_custom_rules)
                return 0;
#endif

        if (fi->fib_net->ipv4.fib_offload_disabled)
                return 0;

        dev = netdev_switch_get_dev_by_nhs(fi);
        if (!dev)
                return 0;
        ops = dev->swdev_ops;

        if (ops->swdev_fib_ipv4_add) {
                err = ops->swdev_fib_ipv4_add(dev, htonl(dst), dst_len,
                                              fi, tos, type, nlflags,
                                              tb_id);
                if (!err)
                        fi->fib_flags |= RTNH_F_OFFLOAD;
        }

        return err;
}
EXPORT_SYMBOL_GPL(netdev_switch_fib_ipv4_add);

/**
 *      netdev_switch_fib_ipv4_del - Delete IPv4 route entry from switch
 *
 *      @dst: route's IPv4 destination address
 *      @dst_len: destination address length (prefix length)
 *      @fi: route FIB info structure
 *      @tos: route TOS
 *      @type: route type
 *      @tb_id: route table ID
 *
 *      Delete IPv4 route entry from switch device.
 */
int netdev_switch_fib_ipv4_del(u32 dst, int dst_len, struct fib_info *fi,
                               u8 tos, u8 type, u32 tb_id)
{
        struct net_device *dev;
        const struct swdev_ops *ops;
        int err = 0;

        if (!(fi->fib_flags & RTNH_F_OFFLOAD))
                return 0;

        dev = netdev_switch_get_dev_by_nhs(fi);
        if (!dev)
                return 0;
        ops = dev->swdev_ops;

        if (ops->swdev_fib_ipv4_del) {
                err = ops->swdev_fib_ipv4_del(dev, htonl(dst), dst_len,
                                              fi, tos, type, tb_id);
                if (!err)
                        fi->fib_flags &= ~RTNH_F_OFFLOAD;
        }

        return err;
}
EXPORT_SYMBOL_GPL(netdev_switch_fib_ipv4_del);

/**
 *      netdev_switch_fib_ipv4_abort - Abort an IPv4 FIB operation
 *
 *      @fi: route FIB info structure
 */
void netdev_switch_fib_ipv4_abort(struct fib_info *fi)
{
        /* There was a problem installing this route to the offload
         * device.  For now, until we come up with more refined
         * policy handling, abruptly end IPv4 fib offloading for
         * for entire net by flushing offload device(s) of all
         * IPv4 routes, and mark IPv4 fib offloading broken from
         * this point forward.
         */

        fib_flush_external(fi->fib_net);
        fi->fib_net->ipv4.fib_offload_disabled = true;
}
EXPORT_SYMBOL_GPL(netdev_switch_fib_ipv4_abort);