linuxdebug/samples/connector/cn_test.c

189 lines
3.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* cn_test.c
*
* 2004+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net>
* All rights reserved.
*/
#define pr_fmt(fmt) "cn_test: " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/timer.h>
#include <linux/connector.h>
static struct cb_id cn_test_id = { CN_NETLINK_USERS + 3, 0x456 };
static char cn_test_name[] = "cn_test";
static struct sock *nls;
static struct timer_list cn_test_timer;
static void cn_test_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
{
pr_info("%s: %lu: idx=%x, val=%x, seq=%u, ack=%u, len=%d: %s.\n",
__func__, jiffies, msg->id.idx, msg->id.val,
msg->seq, msg->ack, msg->len,
msg->len ? (char *)msg->data : "");
}
/*
* Do not remove this function even if no one is using it as
* this is an example of how to get notifications about new
* connector user registration
*/
#if 0
static int cn_test_want_notify(void)
{
struct cn_ctl_msg *ctl;
struct cn_notify_req *req;
struct cn_msg *msg = NULL;
int size, size0;
struct sk_buff *skb;
struct nlmsghdr *nlh;
u32 group = 1;
size0 = sizeof(*msg) + sizeof(*ctl) + 3 * sizeof(*req);
size = NLMSG_SPACE(size0);
skb = alloc_skb(size, GFP_ATOMIC);
if (!skb) {
pr_err("failed to allocate new skb with size=%u\n", size);
return -ENOMEM;
}
nlh = nlmsg_put(skb, 0, 0x123, NLMSG_DONE, size - sizeof(*nlh), 0);
if (!nlh) {
kfree_skb(skb);
return -EMSGSIZE;
}
msg = nlmsg_data(nlh);
memset(msg, 0, size0);
msg->id.idx = -1;
msg->id.val = -1;
msg->seq = 0x123;
msg->ack = 0x345;
msg->len = size0 - sizeof(*msg);
ctl = (struct cn_ctl_msg *)(msg + 1);
ctl->idx_notify_num = 1;
ctl->val_notify_num = 2;
ctl->group = group;
ctl->len = msg->len - sizeof(*ctl);
req = (struct cn_notify_req *)(ctl + 1);
/*
* Idx.
*/
req->first = cn_test_id.idx;
req->range = 10;
/*
* Val 0.
*/
req++;
req->first = cn_test_id.val;
req->range = 10;
/*
* Val 1.
*/
req++;
req->first = cn_test_id.val + 20;
req->range = 10;
NETLINK_CB(skb).dst_group = ctl->group;
//netlink_broadcast(nls, skb, 0, ctl->group, GFP_ATOMIC);
netlink_unicast(nls, skb, 0, 0);
pr_info("request was sent: group=0x%x\n", ctl->group);
return 0;
}
#endif
static u32 cn_test_timer_counter;
static void cn_test_timer_func(struct timer_list *unused)
{
struct cn_msg *m;
char data[32];
pr_debug("%s: timer fired\n", __func__);
m = kzalloc(sizeof(*m) + sizeof(data), GFP_ATOMIC);
if (m) {
memcpy(&m->id, &cn_test_id, sizeof(m->id));
m->seq = cn_test_timer_counter;
m->len = sizeof(data);
m->len =
scnprintf(data, sizeof(data), "counter = %u",
cn_test_timer_counter) + 1;
memcpy(m + 1, data, m->len);
cn_netlink_send(m, 0, 0, GFP_ATOMIC);
kfree(m);
}
cn_test_timer_counter++;
mod_timer(&cn_test_timer, jiffies + msecs_to_jiffies(1000));
}
static int cn_test_init(void)
{
int err;
err = cn_add_callback(&cn_test_id, cn_test_name, cn_test_callback);
if (err)
goto err_out;
cn_test_id.val++;
err = cn_add_callback(&cn_test_id, cn_test_name, cn_test_callback);
if (err) {
cn_del_callback(&cn_test_id);
goto err_out;
}
timer_setup(&cn_test_timer, cn_test_timer_func, 0);
mod_timer(&cn_test_timer, jiffies + msecs_to_jiffies(1000));
pr_info("initialized with id={%u.%u}\n",
cn_test_id.idx, cn_test_id.val);
return 0;
err_out:
if (nls && nls->sk_socket)
sock_release(nls->sk_socket);
return err;
}
static void cn_test_fini(void)
{
del_timer_sync(&cn_test_timer);
cn_del_callback(&cn_test_id);
cn_test_id.val--;
cn_del_callback(&cn_test_id);
if (nls && nls->sk_socket)
sock_release(nls->sk_socket);
}
module_init(cn_test_init);
module_exit(cn_test_fini);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>");
MODULE_DESCRIPTION("Connector's test module");