bonding: Always enable vlan tx offload
[muen/linux.git] / drivers / connector / cn_queue.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *      cn_queue.c
4  *
5  * 2004+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net>
6  * All rights reserved.
7  */
8
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/list.h>
12 #include <linux/workqueue.h>
13 #include <linux/spinlock.h>
14 #include <linux/slab.h>
15 #include <linux/skbuff.h>
16 #include <linux/suspend.h>
17 #include <linux/connector.h>
18 #include <linux/delay.h>
19
20 static struct cn_callback_entry *
21 cn_queue_alloc_callback_entry(struct cn_queue_dev *dev, const char *name,
22                               struct cb_id *id,
23                               void (*callback)(struct cn_msg *,
24                                                struct netlink_skb_parms *))
25 {
26         struct cn_callback_entry *cbq;
27
28         cbq = kzalloc(sizeof(*cbq), GFP_KERNEL);
29         if (!cbq) {
30                 pr_err("Failed to create new callback queue.\n");
31                 return NULL;
32         }
33
34         refcount_set(&cbq->refcnt, 1);
35
36         atomic_inc(&dev->refcnt);
37         cbq->pdev = dev;
38
39         snprintf(cbq->id.name, sizeof(cbq->id.name), "%s", name);
40         memcpy(&cbq->id.id, id, sizeof(struct cb_id));
41         cbq->callback = callback;
42         return cbq;
43 }
44
45 void cn_queue_release_callback(struct cn_callback_entry *cbq)
46 {
47         if (!refcount_dec_and_test(&cbq->refcnt))
48                 return;
49
50         atomic_dec(&cbq->pdev->refcnt);
51         kfree(cbq);
52 }
53
54 int cn_cb_equal(struct cb_id *i1, struct cb_id *i2)
55 {
56         return ((i1->idx == i2->idx) && (i1->val == i2->val));
57 }
58
59 int cn_queue_add_callback(struct cn_queue_dev *dev, const char *name,
60                           struct cb_id *id,
61                           void (*callback)(struct cn_msg *,
62                                            struct netlink_skb_parms *))
63 {
64         struct cn_callback_entry *cbq, *__cbq;
65         int found = 0;
66
67         cbq = cn_queue_alloc_callback_entry(dev, name, id, callback);
68         if (!cbq)
69                 return -ENOMEM;
70
71         spin_lock_bh(&dev->queue_lock);
72         list_for_each_entry(__cbq, &dev->queue_list, callback_entry) {
73                 if (cn_cb_equal(&__cbq->id.id, id)) {
74                         found = 1;
75                         break;
76                 }
77         }
78         if (!found)
79                 list_add_tail(&cbq->callback_entry, &dev->queue_list);
80         spin_unlock_bh(&dev->queue_lock);
81
82         if (found) {
83                 cn_queue_release_callback(cbq);
84                 return -EINVAL;
85         }
86
87         cbq->seq = 0;
88         cbq->group = cbq->id.id.idx;
89
90         return 0;
91 }
92
93 void cn_queue_del_callback(struct cn_queue_dev *dev, struct cb_id *id)
94 {
95         struct cn_callback_entry *cbq, *n;
96         int found = 0;
97
98         spin_lock_bh(&dev->queue_lock);
99         list_for_each_entry_safe(cbq, n, &dev->queue_list, callback_entry) {
100                 if (cn_cb_equal(&cbq->id.id, id)) {
101                         list_del(&cbq->callback_entry);
102                         found = 1;
103                         break;
104                 }
105         }
106         spin_unlock_bh(&dev->queue_lock);
107
108         if (found)
109                 cn_queue_release_callback(cbq);
110 }
111
112 struct cn_queue_dev *cn_queue_alloc_dev(const char *name, struct sock *nls)
113 {
114         struct cn_queue_dev *dev;
115
116         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
117         if (!dev)
118                 return NULL;
119
120         snprintf(dev->name, sizeof(dev->name), "%s", name);
121         atomic_set(&dev->refcnt, 0);
122         INIT_LIST_HEAD(&dev->queue_list);
123         spin_lock_init(&dev->queue_lock);
124
125         dev->nls = nls;
126
127         return dev;
128 }
129
130 void cn_queue_free_dev(struct cn_queue_dev *dev)
131 {
132         struct cn_callback_entry *cbq, *n;
133
134         spin_lock_bh(&dev->queue_lock);
135         list_for_each_entry_safe(cbq, n, &dev->queue_list, callback_entry)
136                 list_del(&cbq->callback_entry);
137         spin_unlock_bh(&dev->queue_lock);
138
139         while (atomic_read(&dev->refcnt)) {
140                 pr_info("Waiting for %s to become free: refcnt=%d.\n",
141                        dev->name, atomic_read(&dev->refcnt));
142                 msleep(1000);
143         }
144
145         kfree(dev);
146         dev = NULL;
147 }