WSL2-Linux-Kernel/net/mctp/neigh.c

142 строки
3.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Management Component Transport Protocol (MCTP) - routing
* implementation.
*
* This is currently based on a simple routing table, with no dst cache. The
* number of routes should stay fairly small, so the lookup cost is small.
*
* Copyright (c) 2021 Code Construct
* Copyright (c) 2021 Google
*/
#include <linux/idr.h>
#include <linux/mctp.h>
#include <linux/netdevice.h>
#include <linux/rtnetlink.h>
#include <linux/skbuff.h>
#include <net/mctp.h>
#include <net/mctpdevice.h>
#include <net/netlink.h>
#include <net/sock.h>
static int __always_unused mctp_neigh_add(struct mctp_dev *mdev, mctp_eid_t eid,
enum mctp_neigh_source source,
size_t lladdr_len, const void *lladdr)
{
struct net *net = dev_net(mdev->dev);
struct mctp_neigh *neigh;
int rc;
mutex_lock(&net->mctp.neigh_lock);
if (mctp_neigh_lookup(mdev, eid, NULL) == 0) {
rc = -EEXIST;
goto out;
}
if (lladdr_len > sizeof(neigh->ha)) {
rc = -EINVAL;
goto out;
}
neigh = kzalloc(sizeof(*neigh), GFP_KERNEL);
if (!neigh) {
rc = -ENOMEM;
goto out;
}
INIT_LIST_HEAD(&neigh->list);
neigh->dev = mdev;
dev_hold(neigh->dev->dev);
neigh->eid = eid;
neigh->source = source;
memcpy(neigh->ha, lladdr, lladdr_len);
list_add_rcu(&neigh->list, &net->mctp.neighbours);
rc = 0;
out:
mutex_unlock(&net->mctp.neigh_lock);
return rc;
}
static void __mctp_neigh_free(struct rcu_head *rcu)
{
struct mctp_neigh *neigh = container_of(rcu, struct mctp_neigh, rcu);
dev_put(neigh->dev->dev);
kfree(neigh);
}
/* Removes all neighbour entries referring to a device */
void mctp_neigh_remove_dev(struct mctp_dev *mdev)
{
struct net *net = dev_net(mdev->dev);
struct mctp_neigh *neigh, *tmp;
mutex_lock(&net->mctp.neigh_lock);
list_for_each_entry_safe(neigh, tmp, &net->mctp.neighbours, list) {
if (neigh->dev == mdev) {
list_del_rcu(&neigh->list);
/* TODO: immediate RTM_DELNEIGH */
call_rcu(&neigh->rcu, __mctp_neigh_free);
}
}
mutex_unlock(&net->mctp.neigh_lock);
}
int mctp_neigh_lookup(struct mctp_dev *mdev, mctp_eid_t eid, void *ret_hwaddr)
{
struct net *net = dev_net(mdev->dev);
struct mctp_neigh *neigh;
int rc = -EHOSTUNREACH; // TODO: or ENOENT?
rcu_read_lock();
list_for_each_entry_rcu(neigh, &net->mctp.neighbours, list) {
if (mdev == neigh->dev && eid == neigh->eid) {
if (ret_hwaddr)
memcpy(ret_hwaddr, neigh->ha,
sizeof(neigh->ha));
rc = 0;
break;
}
}
rcu_read_unlock();
return rc;
}
/* namespace registration */
static int __net_init mctp_neigh_net_init(struct net *net)
{
struct netns_mctp *ns = &net->mctp;
INIT_LIST_HEAD(&ns->neighbours);
return 0;
}
static void __net_exit mctp_neigh_net_exit(struct net *net)
{
struct netns_mctp *ns = &net->mctp;
struct mctp_neigh *neigh;
list_for_each_entry(neigh, &ns->neighbours, list)
call_rcu(&neigh->rcu, __mctp_neigh_free);
}
/* net namespace implementation */
static struct pernet_operations mctp_net_ops = {
.init = mctp_neigh_net_init,
.exit = mctp_neigh_net_exit,
};
int __init mctp_neigh_init(void)
{
return register_pernet_subsys(&mctp_net_ops);
}
void __exit mctp_neigh_exit(void)
{
unregister_pernet_subsys(&mctp_net_ops);
}