/*
* Copyright (c) 2005 Voltaire Inc. All rights reserved.
* Copyright (c) 2002-2005, Network Appliance, Inc. All rights reserved.
* Copyright (c) 1999-2005, Mellanox Technologies, Inc. All rights reserved.
* Copyright (c) 2005 Intel Corporation. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <linux/mutex.h>
#include <linux/inetdevice.h>
#include <linux/workqueue.h>
#include <linux/if_arp.h>
#include <net/arp.h>
#include <net/neighbour.h>
#include <net/route.h>
#include <net/netevent.h>
#include <rdma/ib_addr.h>
MODULE_AUTHOR("Sean Hefty");
MODULE_DESCRIPTION("IB Address Translation");
MODULE_LICENSE("Dual BSD/GPL");
struct addr_req {
struct list_head list;
struct sockaddr src_addr;
struct sockaddr dst_addr;
struct rdma_dev_addr *addr;
struct rdma_addr_client *client;
void *context;
void (*callback)(int status, struct sockaddr *src_addr,
struct rdma_dev_addr *addr, void *context);
unsigned long timeout;
int status;
};
static void process_req(struct work_struct *work);
static DEFINE_MUTEX(lock);
static LIST_HEAD(req_list);
static DECLARE_DELAYED_WORK(work, process_req);
static struct workqueue_struct *addr_wq;
void rdma_addr_register_client(struct rdma_addr_client *client)
{
atomic_set(&client->refcount, 1);
init_completion(&client->comp);
}
EXPORT_SYMBOL(rdma_addr_register_client);
static inline void put_client(struct rdma_addr_client *client)
{
if (atomic_dec_and_test(&client->refcount))
complete(&client->comp);
}
void rdma_addr_unregister_client(struct rdma_addr_client *client)
{
put_client(client);
wait_for_completion(&client->comp);
}
EXPORT_SYMBOL(rdma_addr_unregister_client);
int rdma_copy_addr(struct rdma_dev_addr *dev_addr, struct net_device *dev,
const unsigned char *dst_dev_addr)
{
switch (dev->type) {
case ARPHRD_INFINIBAND:
dev_addr->dev_type = RDMA_NODE_IB_CA;
break;
case ARPHRD_ETHER:
dev_addr->dev_type = RDMA_NODE_RNIC;
break;
default:
return -EADDRNOTAVAIL;
}
memcpy(dev_addr->src_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
memcpy(dev_addr->broadcast, dev->broadcast, MAX_ADDR_LEN);
if (dst_dev_addr)
memcpy(dev_addr->dst_dev_addr, dst_dev_addr, MAX_ADDR_LEN);
dev_addr->src_dev = dev;
return 0;
}
EXPORT_SYMBOL(rdma_copy_addr);
int rdma_translate_ip(struct sockaddr *addr, struct rdma_dev_addr *dev_addr)
{
struct net_device *dev;
__be32 ip = ((struct sockaddr_in *) addr)->sin_addr.s_addr;
int ret;
dev = ip_dev_find(&init_net, ip);
if (!dev)
return -EADDRNOTAVAIL;
ret = rdma_copy_addr(dev_addr, dev, NULL);
dev_put(dev);
return ret;
}
EXPORT_SYMBOL(rdma_translate_ip);
static void set_timeout(unsigned long time)
{
unsigned long delay;
cancel_delayed_work(&work);
delay = time - jiffies;
if ((long)delay <= 0)
delay = 1;
queue_delayed_work(addr_wq, &work, delay);
}
static void queue_req(struct addr_req *req)
{
struct addr_req *temp_req;
mutex_lock(&lock);
list_for_each_entry_reverse(temp_req, &req_list, list) {
if (time_after_eq(req->timeout, temp_req->timeout))
break;
}
list_add(&req->list, &temp_req->list);
if (req_list.next == &req->list)
set_timeout(req->timeout);
mutex_unlock(&lock);
}
static void addr_send_arp(struct sockaddr_in *dst_in)
{
struct rtable *rt;
struct flowi fl;
__be32 dst_ip = dst_in->sin_addr.s_addr;
memset(&fl, 0, sizeof fl);
fl.nl_u.ip4_u.daddr = dst_ip;
if (ip_route_output_key(&init_net, &rt, &fl))
return;
neigh_event_send(rt->u.dst.neighbour, NULL);
ip_rt_put(rt);
}
static int addr_resolve_remote(struct sockaddr_in *src_in,
struct sockaddr_in *dst_in,
struct rdma_dev_addr *addr)
{
__be32 src_ip = src_in->sin_addr.s_addr;
__be32 dst_ip = dst_in->sin_addr.s_addr;
struct flowi fl;
struct rtable *rt;
struct neighbour *neigh;
int ret;
memset(&fl, 0, sizeof fl);
fl.nl_u.ip4_u.daddr = dst_ip;
fl.nl_u.ip4_u.saddr = src_ip;
ret = ip_route_output_key(&init_net, &rt, &fl);
if (ret)
goto out;
/* If the device does ARP internally, return 'done' */
if (rt->idev->dev->flags & IFF_NOARP) {
rdma_copy_addr(addr, rt->idev->dev, NULL);
goto put;
}
neigh = neigh_lookup(&arp_tbl, &rt->rt_gateway, rt->idev->dev);
if (!neigh) {
ret = -ENODATA;
goto put;
}
if (!(neigh->nud_state & NUD_VALID)) {
ret = -ENODATA;
goto release;
}
if (!src_ip) {
src_in->sin_family = dst_in->sin_family;
src_in->sin_addr.s_addr = rt->rt_src;
}
ret = rdma_copy_addr(addr, neigh->dev, neigh->ha);
release:
neigh_release(neigh);
put:
ip_rt_put(rt);
out:
return ret;
}
static void process_req(struct work_struct *work)
{
struct addr_req *req, *temp_req;
struct sockaddr_in *src_in, *dst_in;
struct list_head done_list;
INIT_LIST_HEAD(&done_list);
mutex_lock(&lock);
list_for_each_entry_safe(req, temp_req, &req_list, list) {
if (req->status == -ENODATA) {
src_in = (struct sockaddr_in *) &req->src_addr;
dst_in = (struct sockaddr_in *) &req->dst_addr;
req->status = addr_resolve_remote(src_in, dst_in,
req->addr);
if (req->status && time_after_eq(jiffies, req->timeout))
req->status = -ETIMEDOUT;
else if (req->status == -ENODATA)
continue;
}
list_move_tail(&req->list, &done_list);
}
if (!list_empty(&req_list)) {
req = list_entry(req_list.next, struct addr_req, list);
set_timeout(req->timeout);
}
mutex_unlock(&lock);
list_for_each_entry_safe(req, temp_req, &done_list, list) {
list_del(&req->list);
req->callback(req->status, &req->src_addr, req->addr,
req->context);
put_client(req->client);
kfree(req);
}
}
static int addr_resolve_local(struct sockaddr_in *src_in,
struct sockaddr_in *dst_in,
struct rdma_dev_addr *addr)
{
struct net_device *dev;
__be32 src_ip = src_in->sin_addr.s_addr;
__be32 dst_ip = dst_in->sin_addr.s_addr;
int ret;
dev = ip_dev_find(&init_net, dst_ip);
if (!dev)
return -EADDRNOTAVAIL;
if (ipv4_is_zeronet(src_ip)) {
src_in->sin_family = dst_in->sin_family;
src_in->sin_addr.s_addr = dst_ip;
ret = rdma_copy_addr(addr, dev, dev->dev_addr);
} else if (ipv4_is_loopback(src_ip)) {
ret = rdma_translate_ip((struct sockaddr *)dst_in, addr);
if (!ret)
memcpy(addr->dst_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
} else {
ret = rdma_translate_ip((struct sockaddr *)src_in, addr);
if (!ret)
memcpy(addr->dst_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
}
dev_put(dev);
return ret;
}
int rdma_resolve_ip(struct rdma_addr_client *client,
struct sockaddr *src_addr, struct sockaddr *dst_addr,
struct rdma_dev_addr *addr, int timeout_ms,
void (*callback)(int status, struct sockaddr *src_addr,
struct rdma_dev_addr *addr, void *context),
void *context)
{
struct sockaddr_in *src_in, *dst_in;
struct addr_req *req;
int ret = 0;
req = kzalloc(sizeof *req, GFP_KERNEL);
if (!req)
return -ENOMEM;
if (src_addr)
memcpy(&req->src_addr, src_addr, ip_addr_size(src_addr));
memcpy(&req->dst_addr, dst_addr, ip_addr_size(dst_addr));
req->addr = addr;
req->callback = callback;
req->context = context;
req->client = client;
atomic_inc(&client->refcount);
src_in = (struct sockaddr_in *) &req->src_addr;
dst_in = (struct sockaddr_in *) &req->dst_addr;
req->status = addr_resolve_local(src_in, dst_in, addr);
if (req->status == -EADDRNOTAVAIL)
req->status = addr_resolve_remote(src_in, dst_in, addr);
switch (req->status) {
case 0:
req->timeout = jiffies;
queue_req(req);
break;
case -ENODATA:
req->timeout = msecs_to_jiffies(timeout_ms) + jiffies;
queue_req(req);
addr_send_arp(dst_in);
break;
default:
ret = req->status;
atomic_dec(&client->refcount);
kfree(req);
break;
}
return ret;
}
EXPORT_SYMBOL(rdma_resolve_ip);
void rdma_addr_cancel(struct rdma_dev_addr *addr)
{
struct addr_req *req, *temp_req;
mutex_lock(&lock);
list_for_each_entry_safe(req, temp_req, &req_list, list) {
if (req->addr == addr) {
req->status = -ECANCELED;
req->timeout = jiffies;
list_move(&req->list, &req_list);
set_timeout(req->timeout);
break;
}
}
mutex_unlock(&lock);
}
EXPORT_SYMBOL(rdma_addr_cancel);
static int netevent_callback(struct notifier_block *self, unsigned long event,
void *ctx)
{
if (event == NETEVENT_NEIGH_UPDATE) {
struct neighbour *neigh = ctx;
if (neigh->nud_state & NUD_VALID) {
set_timeout(jiffies);
}
}
return 0;
}
static struct notifier_block nb = {
.notifier_call = netevent_callback
};
static int addr_init(void)
{
addr_wq = create_singlethread_workqueue("ib_addr");
if (!addr_wq)
return -ENOMEM;
register_netevent_notifier(&nb);
return 0;
}
static void addr_cleanup(void)
{
unregister_netevent_notifier(&nb);
destroy_workqueue(addr_wq);
}
module_init(addr_init);
module_exit(addr_cleanup);
