mirror of https://gitee.com/openkylin/linux.git
148 lines
3.2 KiB
C
148 lines
3.2 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* cn_queue.c
|
|
*
|
|
* 2004+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net>
|
|
* All rights reserved.
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/list.h>
|
|
#include <linux/workqueue.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/suspend.h>
|
|
#include <linux/connector.h>
|
|
#include <linux/delay.h>
|
|
|
|
static struct cn_callback_entry *
|
|
cn_queue_alloc_callback_entry(struct cn_queue_dev *dev, const char *name,
|
|
const struct cb_id *id,
|
|
void (*callback)(struct cn_msg *,
|
|
struct netlink_skb_parms *))
|
|
{
|
|
struct cn_callback_entry *cbq;
|
|
|
|
cbq = kzalloc(sizeof(*cbq), GFP_KERNEL);
|
|
if (!cbq) {
|
|
pr_err("Failed to create new callback queue.\n");
|
|
return NULL;
|
|
}
|
|
|
|
refcount_set(&cbq->refcnt, 1);
|
|
|
|
atomic_inc(&dev->refcnt);
|
|
cbq->pdev = dev;
|
|
|
|
snprintf(cbq->id.name, sizeof(cbq->id.name), "%s", name);
|
|
memcpy(&cbq->id.id, id, sizeof(struct cb_id));
|
|
cbq->callback = callback;
|
|
return cbq;
|
|
}
|
|
|
|
void cn_queue_release_callback(struct cn_callback_entry *cbq)
|
|
{
|
|
if (!refcount_dec_and_test(&cbq->refcnt))
|
|
return;
|
|
|
|
atomic_dec(&cbq->pdev->refcnt);
|
|
kfree(cbq);
|
|
}
|
|
|
|
int cn_cb_equal(const struct cb_id *i1, const struct cb_id *i2)
|
|
{
|
|
return ((i1->idx == i2->idx) && (i1->val == i2->val));
|
|
}
|
|
|
|
int cn_queue_add_callback(struct cn_queue_dev *dev, const char *name,
|
|
const struct cb_id *id,
|
|
void (*callback)(struct cn_msg *,
|
|
struct netlink_skb_parms *))
|
|
{
|
|
struct cn_callback_entry *cbq, *__cbq;
|
|
int found = 0;
|
|
|
|
cbq = cn_queue_alloc_callback_entry(dev, name, id, callback);
|
|
if (!cbq)
|
|
return -ENOMEM;
|
|
|
|
spin_lock_bh(&dev->queue_lock);
|
|
list_for_each_entry(__cbq, &dev->queue_list, callback_entry) {
|
|
if (cn_cb_equal(&__cbq->id.id, id)) {
|
|
found = 1;
|
|
break;
|
|
}
|
|
}
|
|
if (!found)
|
|
list_add_tail(&cbq->callback_entry, &dev->queue_list);
|
|
spin_unlock_bh(&dev->queue_lock);
|
|
|
|
if (found) {
|
|
cn_queue_release_callback(cbq);
|
|
return -EINVAL;
|
|
}
|
|
|
|
cbq->seq = 0;
|
|
cbq->group = cbq->id.id.idx;
|
|
|
|
return 0;
|
|
}
|
|
|
|
void cn_queue_del_callback(struct cn_queue_dev *dev, const struct cb_id *id)
|
|
{
|
|
struct cn_callback_entry *cbq, *n;
|
|
int found = 0;
|
|
|
|
spin_lock_bh(&dev->queue_lock);
|
|
list_for_each_entry_safe(cbq, n, &dev->queue_list, callback_entry) {
|
|
if (cn_cb_equal(&cbq->id.id, id)) {
|
|
list_del(&cbq->callback_entry);
|
|
found = 1;
|
|
break;
|
|
}
|
|
}
|
|
spin_unlock_bh(&dev->queue_lock);
|
|
|
|
if (found)
|
|
cn_queue_release_callback(cbq);
|
|
}
|
|
|
|
struct cn_queue_dev *cn_queue_alloc_dev(const char *name, struct sock *nls)
|
|
{
|
|
struct cn_queue_dev *dev;
|
|
|
|
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
|
|
if (!dev)
|
|
return NULL;
|
|
|
|
snprintf(dev->name, sizeof(dev->name), "%s", name);
|
|
atomic_set(&dev->refcnt, 0);
|
|
INIT_LIST_HEAD(&dev->queue_list);
|
|
spin_lock_init(&dev->queue_lock);
|
|
|
|
dev->nls = nls;
|
|
|
|
return dev;
|
|
}
|
|
|
|
void cn_queue_free_dev(struct cn_queue_dev *dev)
|
|
{
|
|
struct cn_callback_entry *cbq, *n;
|
|
|
|
spin_lock_bh(&dev->queue_lock);
|
|
list_for_each_entry_safe(cbq, n, &dev->queue_list, callback_entry)
|
|
list_del(&cbq->callback_entry);
|
|
spin_unlock_bh(&dev->queue_lock);
|
|
|
|
while (atomic_read(&dev->refcnt)) {
|
|
pr_info("Waiting for %s to become free: refcnt=%d.\n",
|
|
dev->name, atomic_read(&dev->refcnt));
|
|
msleep(1000);
|
|
}
|
|
|
|
kfree(dev);
|
|
dev = NULL;
|
|
}
|