1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
|
/*
* cn_queue.c
*
* 2004-2005 Copyright (c) Evgeniy Polyakov <johnpol@2ka.mipt.ru>
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#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>
void cn_queue_wrapper(void *data)
{
struct cn_callback_data *d = data;
d->callback(d->callback_priv);
d->destruct_data(d->ddata);
d->ddata = NULL;
kfree(d->free);
}
static struct cn_callback_entry *cn_queue_alloc_callback_entry(char *name, struct cb_id *id, void (*callback)(void *))
{
struct cn_callback_entry *cbq;
cbq = kzalloc(sizeof(*cbq), GFP_KERNEL);
if (!cbq) {
printk(KERN_ERR "Failed to create new callback queue.\n");
return NULL;
}
snprintf(cbq->id.name, sizeof(cbq->id.name), "%s", name);
memcpy(&cbq->id.id, id, sizeof(struct cb_id));
cbq->data.callback = callback;
INIT_WORK(&cbq->work, &cn_queue_wrapper, &cbq->data);
return cbq;
}
static void cn_queue_free_callback(struct cn_callback_entry *cbq)
{
cancel_delayed_work(&cbq->work);
flush_workqueue(cbq->pdev->cn_queue);
kfree(cbq);
}
int cn_cb_equal(struct cb_id *i1, struct cb_id *i2)
{
return ((i1->idx == i2->idx) && (i1->val == i2->val));
}
int cn_queue_add_callback(struct cn_queue_dev *dev, char *name, struct cb_id *id, void (*callback)(void *))
{
struct cn_callback_entry *cbq, *__cbq;
int found = 0;
cbq = cn_queue_alloc_callback_entry(name, id, callback);
if (!cbq)
return -ENOMEM;
atomic_inc(&dev->refcnt);
cbq->pdev = dev;
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) {
atomic_dec(&dev->refcnt);
cn_queue_free_callback(cbq);
return -EINVAL;
}
cbq->nls = dev->nls;
cbq->seq = 0;
cbq->group = cbq->id.id.idx;
return 0;
}
void cn_queue_del_callback(struct cn_queue_dev *dev, 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_free_callback(cbq);
atomic_dec_and_test(&dev->refcnt);
}
}
struct cn_queue_dev *cn_queue_alloc_dev(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;
dev->netlink_groups = 0;
dev->cn_queue = create_workqueue(dev->name);
if (!dev->cn_queue) {
kfree(dev);
return NULL;
}
return dev;
}
void cn_queue_free_dev(struct cn_queue_dev *dev)
{
struct cn_callback_entry *cbq, *n;
flush_workqueue(dev->cn_queue);
destroy_workqueue(dev->cn_queue);
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)) {
printk(KERN_INFO "Waiting for %s to become free: refcnt=%d.\n",
dev->name, atomic_read(&dev->refcnt));
msleep(1000);
}
kfree(dev);
dev = NULL;
}
|
