/*
* Copyright (c) 2010 Voltaire Inc. 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.
*/
#define pr_fmt(fmt) "%s:%s: " fmt, KBUILD_MODNAME, __func__
#include <linux/export.h>
#include <net/netlink.h>
#include <net/net_namespace.h>
#include <net/sock.h>
#include <rdma/rdma_netlink.h>
struct ibnl_client {
struct list_head list;
int index;
int nops;
const struct ibnl_client_cbs *cb_table;
};
static DEFINE_MUTEX(ibnl_mutex);
static struct sock *nls;
static LIST_HEAD(client_list);
int ibnl_chk_listeners(unsigned int group)
{
if (netlink_has_listeners(nls, group) == 0)
return -1;
return 0;
}
EXPORT_SYMBOL(ibnl_chk_listeners);
int ibnl_add_client(int index, int nops,
const struct ibnl_client_cbs cb_table[])
{
struct ibnl_client *cur;
struct ibnl_client *nl_client;
nl_client = kmalloc(sizeof *nl_client, GFP_KERNEL);
if (!nl_client)
return -ENOMEM;
nl_client->index = index;
nl_client->nops = nops;
nl_client->cb_table = cb_table;
mutex_lock(&ibnl_mutex);
list_for_each_entry(cur, &client_list, list) {
if (cur->index == index) {
pr_warn("Client for %d already exists\n", index);
mutex_unlock(&ibnl_mutex);
kfree(nl_client);
return -EINVAL;
}
}
list_add_tail(&nl_client->list, &client_list);
mutex_unlock(&ibnl_mutex);
return 0;
}
EXPORT_SYMBOL(ibnl_add_client);
int ibnl_remove_client(int index)
{
struct ibnl_client *cur, *next;
mutex_lock(&ibnl_mutex);
list_for_each_entry_safe(cur, next, &client_list, list) {
if (cur->index == index) {
list_del(&(cur->list));
mutex_unlock(&ibnl_mutex);
kfree(cur);
return 0;
}
}
pr_warn("Can't remove callback for client idx %d. Not found\n", index);
mutex_unlock(&ibnl_mutex);
return -EINVAL;
}
EXPORT_SYMBOL(ibnl_remove_client);
void *ibnl_put_msg(struct sk_buff *skb, struct nlmsghdr **nlh, int seq,
int len, int client, int op, int flags)
{
unsigned char *prev_tail;
prev_tail = skb_tail_pointer(skb);
*nlh = nlmsg_put(skb, 0, seq, RDMA_NL_GET_TYPE(client, op),
len, flags);
if (!*nlh)
goto out_nlmsg_trim;
(*nlh)->nlmsg_len = skb_tail_pointer(skb) - prev_tail;
return nlmsg_data(*nlh);
out_nlmsg_trim:
nlmsg_trim(skb, prev_tail);
return NULL;
}
EXPORT_SYMBOL(ibnl_put_msg);
int ibnl_put_attr(struct sk_buff *skb, struct nlmsghdr *nlh,
int len, void *data, int type)
{
unsigned char *prev_tail;
prev_tail = skb_tail_pointer(skb);
if (nla_put(skb, type, len, data))
goto nla_put_failure;
nlh->nlmsg_len += skb_tail_pointer(skb) - prev_tail;
return 0;
nla_put_failure:
nlmsg_trim(skb, prev_tail - nlh->nlmsg_len);
return -EMSGSIZE;
}
EXPORT_SYMBOL(ibnl_put_attr);
static int ibnl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
{
struct ibnl_client *client;
int type = nlh->nlmsg_type;
int index = RDMA_NL_GET_CLIENT(type);
int op = RDMA_NL_GET_OP(type);
list_for_each_entry(client, &client_list, list) {
if (client->index == index) {
if (op < 0 || op >= client->nops ||
!client->cb_table[op].dump)
return -EINVAL;
/*
* For response or local service set_timeout request,
* there is no need to use netlink_dump_start.
*/
if (!(nlh->nlmsg_flags & NLM_F_REQUEST) ||
(index == RDMA_NL_LS &&
op == RDMA_NL_LS_OP_SET_TIMEOUT)) {
struct netlink_callback cb = {
.skb = skb,
.nlh = nlh,
.dump = client->cb_table[op].dump,
.module = client->cb_table[op].module,
};
return cb.dump(skb, &cb);
}
{
struct netlink_dump_control c = {
.dump = client->cb_table[op].dump,
.module = client->cb_table[op].module,
};
return netlink_dump_start(nls, skb, nlh, &c);
}
}
}
pr_info("Index %d wasn't found in client list\n", index);
return -EINVAL;
}
static void ibnl_rcv_reply_skb(struct sk_buff *skb)
{
struct nlmsghdr *nlh;
int msglen;
/*
* Process responses until there is no more message or the first
* request. Generally speaking, it is not recommended to mix responses
* with requests.
*/
while (skb->len >= nlmsg_total_size(0)) {
nlh = nlmsg_hdr(skb);
if (nlh->nlmsg_len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len)
return;
/* Handle response only */
if (nlh->nlmsg_flags & NLM_F_REQUEST)
return;
ibnl_rcv_msg(skb, nlh);
msglen = NLMSG_ALIGN(nlh->nlmsg_len);
if (msglen > skb->len)
msglen = skb->len;
skb_pull(skb, msglen);
}
}
static void ibnl_rcv(struct sk_buff *skb)
{
mutex_lock(&ibnl_mutex);
ibnl_rcv_reply_skb(skb);
netlink_rcv_skb(skb, &ibnl_rcv_msg);
mutex_unlock(&ibnl_mutex);
}
int ibnl_unicast(struct sk_buff *skb, struct nlmsghdr *nlh,
__u32 pid)
{
return nlmsg_unicast(nls, skb, pid);
}
EXPORT_SYMBOL(ibnl_unicast);
int ibnl_multicast(struct sk_buff *skb, struct nlmsghdr *nlh,
unsigned int group, gfp_t flags)
{
return nlmsg_multicast(nls, skb, 0, group, flags);
}
EXPORT_SYMBOL(ibnl_multicast);
int __init ibnl_init(void)
{
struct netlink_kernel_cfg cfg = {
.input = ibnl_rcv,
};
nls = netlink_kernel_create(&init_net, NETLINK_RDMA, &cfg);
if (!nls) {
pr_warn("Failed to create netlink socket\n");
return -ENOMEM;
}
return 0;
}
void ibnl_cleanup(void)
{
struct ibnl_client *cur, *next;
mutex_lock(&ibnl_mutex);
list_for_each_entry_safe(cur, next, &client_list, list) {
list_del(&(cur->list));
kfree(cur);
}
mutex_unlock(&ibnl_mutex);
netlink_kernel_release(nls);
}
