Commit | Line | Data |
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7672d0b5 EP |
1 | /* |
2 | * cn_queue.c | |
1a5645bc | 3 | * |
acb9c1b2 | 4 | * 2004+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net> |
7672d0b5 | 5 | * All rights reserved. |
1a5645bc | 6 | * |
7672d0b5 EP |
7 | * This program is free software; you can redistribute it and/or modify |
8 | * it under the terms of the GNU General Public License as published by | |
9 | * the Free Software Foundation; either version 2 of the License, or | |
10 | * (at your option) any later version. | |
11 | * | |
12 | * This program is distributed in the hope that it will be useful, | |
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | * GNU General Public License for more details. | |
16 | * | |
17 | * You should have received a copy of the GNU General Public License | |
18 | * along with this program; if not, write to the Free Software | |
19 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
20 | * | |
21 | */ | |
22 | ||
23 | #include <linux/kernel.h> | |
24 | #include <linux/module.h> | |
25 | #include <linux/list.h> | |
26 | #include <linux/workqueue.h> | |
27 | #include <linux/spinlock.h> | |
28 | #include <linux/slab.h> | |
29 | #include <linux/skbuff.h> | |
30 | #include <linux/suspend.h> | |
31 | #include <linux/connector.h> | |
32 | #include <linux/delay.h> | |
33 | ||
0741241c | 34 | static struct cn_callback_entry * |
04f482fa PM |
35 | cn_queue_alloc_callback_entry(struct cn_queue_dev *dev, const char *name, |
36 | struct cb_id *id, | |
7069331d | 37 | void (*callback)(struct cn_msg *, struct netlink_skb_parms *)) |
7672d0b5 EP |
38 | { |
39 | struct cn_callback_entry *cbq; | |
40 | ||
41 | cbq = kzalloc(sizeof(*cbq), GFP_KERNEL); | |
42 | if (!cbq) { | |
43 | printk(KERN_ERR "Failed to create new callback queue.\n"); | |
44 | return NULL; | |
45 | } | |
46 | ||
04f482fa PM |
47 | atomic_set(&cbq->refcnt, 1); |
48 | ||
49 | atomic_inc(&dev->refcnt); | |
50 | cbq->pdev = dev; | |
51 | ||
acd042bb EP |
52 | snprintf(cbq->id.name, sizeof(cbq->id.name), "%s", name); |
53 | memcpy(&cbq->id.id, id, sizeof(struct cb_id)); | |
04f482fa | 54 | cbq->callback = callback; |
7672d0b5 EP |
55 | return cbq; |
56 | } | |
57 | ||
04f482fa | 58 | void cn_queue_release_callback(struct cn_callback_entry *cbq) |
7672d0b5 | 59 | { |
04f482fa PM |
60 | if (!atomic_dec_and_test(&cbq->refcnt)) |
61 | return; | |
62 | ||
63 | atomic_dec(&cbq->pdev->refcnt); | |
7672d0b5 EP |
64 | kfree(cbq); |
65 | } | |
66 | ||
67 | int cn_cb_equal(struct cb_id *i1, struct cb_id *i2) | |
68 | { | |
69 | return ((i1->idx == i2->idx) && (i1->val == i2->val)); | |
70 | } | |
71 | ||
008536e8 JP |
72 | int cn_queue_add_callback(struct cn_queue_dev *dev, const char *name, |
73 | struct cb_id *id, | |
7069331d | 74 | void (*callback)(struct cn_msg *, struct netlink_skb_parms *)) |
7672d0b5 EP |
75 | { |
76 | struct cn_callback_entry *cbq, *__cbq; | |
77 | int found = 0; | |
78 | ||
04f482fa | 79 | cbq = cn_queue_alloc_callback_entry(dev, name, id, callback); |
7672d0b5 EP |
80 | if (!cbq) |
81 | return -ENOMEM; | |
82 | ||
7672d0b5 EP |
83 | spin_lock_bh(&dev->queue_lock); |
84 | list_for_each_entry(__cbq, &dev->queue_list, callback_entry) { | |
acd042bb | 85 | if (cn_cb_equal(&__cbq->id.id, id)) { |
7672d0b5 EP |
86 | found = 1; |
87 | break; | |
88 | } | |
89 | } | |
90 | if (!found) | |
91 | list_add_tail(&cbq->callback_entry, &dev->queue_list); | |
92 | spin_unlock_bh(&dev->queue_lock); | |
93 | ||
94 | if (found) { | |
04f482fa | 95 | cn_queue_release_callback(cbq); |
7672d0b5 EP |
96 | return -EINVAL; |
97 | } | |
98 | ||
7672d0b5 | 99 | cbq->seq = 0; |
acd042bb | 100 | cbq->group = cbq->id.id.idx; |
7672d0b5 EP |
101 | |
102 | return 0; | |
103 | } | |
104 | ||
105 | void cn_queue_del_callback(struct cn_queue_dev *dev, struct cb_id *id) | |
106 | { | |
107 | struct cn_callback_entry *cbq, *n; | |
108 | int found = 0; | |
109 | ||
110 | spin_lock_bh(&dev->queue_lock); | |
111 | list_for_each_entry_safe(cbq, n, &dev->queue_list, callback_entry) { | |
acd042bb | 112 | if (cn_cb_equal(&cbq->id.id, id)) { |
7672d0b5 EP |
113 | list_del(&cbq->callback_entry); |
114 | found = 1; | |
115 | break; | |
116 | } | |
117 | } | |
118 | spin_unlock_bh(&dev->queue_lock); | |
119 | ||
04f482fa PM |
120 | if (found) |
121 | cn_queue_release_callback(cbq); | |
7672d0b5 EP |
122 | } |
123 | ||
008536e8 | 124 | struct cn_queue_dev *cn_queue_alloc_dev(const char *name, struct sock *nls) |
7672d0b5 EP |
125 | { |
126 | struct cn_queue_dev *dev; | |
127 | ||
128 | dev = kzalloc(sizeof(*dev), GFP_KERNEL); | |
129 | if (!dev) | |
130 | return NULL; | |
131 | ||
132 | snprintf(dev->name, sizeof(dev->name), "%s", name); | |
133 | atomic_set(&dev->refcnt, 0); | |
134 | INIT_LIST_HEAD(&dev->queue_list); | |
135 | spin_lock_init(&dev->queue_lock); | |
136 | ||
137 | dev->nls = nls; | |
7672d0b5 | 138 | |
7672d0b5 EP |
139 | return dev; |
140 | } | |
141 | ||
142 | void cn_queue_free_dev(struct cn_queue_dev *dev) | |
143 | { | |
144 | struct cn_callback_entry *cbq, *n; | |
145 | ||
7672d0b5 EP |
146 | spin_lock_bh(&dev->queue_lock); |
147 | list_for_each_entry_safe(cbq, n, &dev->queue_list, callback_entry) | |
148 | list_del(&cbq->callback_entry); | |
149 | spin_unlock_bh(&dev->queue_lock); | |
150 | ||
151 | while (atomic_read(&dev->refcnt)) { | |
152 | printk(KERN_INFO "Waiting for %s to become free: refcnt=%d.\n", | |
153 | dev->name, atomic_read(&dev->refcnt)); | |
154 | msleep(1000); | |
155 | } | |
156 | ||
157 | kfree(dev); | |
158 | dev = NULL; | |
159 | } |