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 | ||
c4028958 | 34 | void cn_queue_wrapper(struct work_struct *work) |
7672d0b5 | 35 | { |
c4028958 | 36 | struct cn_callback_entry *cbq = |
a240d9f1 | 37 | container_of(work, struct cn_callback_entry, work); |
c4028958 | 38 | struct cn_callback_data *d = &cbq->data; |
293500a2 | 39 | struct cn_msg *msg = NLMSG_DATA(nlmsg_hdr(d->skb)); |
7069331d | 40 | struct netlink_skb_parms *nsp = &NETLINK_CB(d->skb); |
7672d0b5 | 41 | |
7069331d | 42 | d->callback(msg, nsp); |
acd042bb | 43 | |
f1489cfb PR |
44 | kfree_skb(d->skb); |
45 | d->skb = NULL; | |
acd042bb EP |
46 | |
47 | kfree(d->free); | |
7672d0b5 EP |
48 | } |
49 | ||
0741241c MF |
50 | static struct cn_callback_entry * |
51 | cn_queue_alloc_callback_entry(char *name, struct cb_id *id, | |
7069331d | 52 | void (*callback)(struct cn_msg *, struct netlink_skb_parms *)) |
7672d0b5 EP |
53 | { |
54 | struct cn_callback_entry *cbq; | |
55 | ||
56 | cbq = kzalloc(sizeof(*cbq), GFP_KERNEL); | |
57 | if (!cbq) { | |
58 | printk(KERN_ERR "Failed to create new callback queue.\n"); | |
59 | return NULL; | |
60 | } | |
61 | ||
acd042bb EP |
62 | snprintf(cbq->id.name, sizeof(cbq->id.name), "%s", name); |
63 | memcpy(&cbq->id.id, id, sizeof(struct cb_id)); | |
64 | cbq->data.callback = callback; | |
1a5645bc | 65 | |
a240d9f1 | 66 | INIT_WORK(&cbq->work, &cn_queue_wrapper); |
7672d0b5 EP |
67 | return cbq; |
68 | } | |
69 | ||
70 | static void cn_queue_free_callback(struct cn_callback_entry *cbq) | |
71 | { | |
6cebb17b | 72 | flush_workqueue(cbq->pdev->cn_queue); |
7672d0b5 EP |
73 | kfree(cbq); |
74 | } | |
75 | ||
76 | int cn_cb_equal(struct cb_id *i1, struct cb_id *i2) | |
77 | { | |
78 | return ((i1->idx == i2->idx) && (i1->val == i2->val)); | |
79 | } | |
80 | ||
0741241c | 81 | int cn_queue_add_callback(struct cn_queue_dev *dev, char *name, struct cb_id *id, |
7069331d | 82 | void (*callback)(struct cn_msg *, struct netlink_skb_parms *)) |
7672d0b5 EP |
83 | { |
84 | struct cn_callback_entry *cbq, *__cbq; | |
85 | int found = 0; | |
86 | ||
acd042bb | 87 | cbq = cn_queue_alloc_callback_entry(name, id, callback); |
7672d0b5 EP |
88 | if (!cbq) |
89 | return -ENOMEM; | |
90 | ||
91 | atomic_inc(&dev->refcnt); | |
92 | cbq->pdev = dev; | |
93 | ||
94 | spin_lock_bh(&dev->queue_lock); | |
95 | list_for_each_entry(__cbq, &dev->queue_list, callback_entry) { | |
acd042bb | 96 | if (cn_cb_equal(&__cbq->id.id, id)) { |
7672d0b5 EP |
97 | found = 1; |
98 | break; | |
99 | } | |
100 | } | |
101 | if (!found) | |
102 | list_add_tail(&cbq->callback_entry, &dev->queue_list); | |
103 | spin_unlock_bh(&dev->queue_lock); | |
104 | ||
105 | if (found) { | |
7672d0b5 | 106 | cn_queue_free_callback(cbq); |
cf585ae8 | 107 | atomic_dec(&dev->refcnt); |
7672d0b5 EP |
108 | return -EINVAL; |
109 | } | |
110 | ||
7672d0b5 | 111 | cbq->seq = 0; |
acd042bb | 112 | cbq->group = cbq->id.id.idx; |
7672d0b5 EP |
113 | |
114 | return 0; | |
115 | } | |
116 | ||
117 | void cn_queue_del_callback(struct cn_queue_dev *dev, struct cb_id *id) | |
118 | { | |
119 | struct cn_callback_entry *cbq, *n; | |
120 | int found = 0; | |
121 | ||
122 | spin_lock_bh(&dev->queue_lock); | |
123 | list_for_each_entry_safe(cbq, n, &dev->queue_list, callback_entry) { | |
acd042bb | 124 | if (cn_cb_equal(&cbq->id.id, id)) { |
7672d0b5 EP |
125 | list_del(&cbq->callback_entry); |
126 | found = 1; | |
127 | break; | |
128 | } | |
129 | } | |
130 | spin_unlock_bh(&dev->queue_lock); | |
131 | ||
132 | if (found) { | |
133 | cn_queue_free_callback(cbq); | |
cec6f7f3 | 134 | atomic_dec(&dev->refcnt); |
7672d0b5 EP |
135 | } |
136 | } | |
137 | ||
138 | struct cn_queue_dev *cn_queue_alloc_dev(char *name, struct sock *nls) | |
139 | { | |
140 | struct cn_queue_dev *dev; | |
141 | ||
142 | dev = kzalloc(sizeof(*dev), GFP_KERNEL); | |
143 | if (!dev) | |
144 | return NULL; | |
145 | ||
146 | snprintf(dev->name, sizeof(dev->name), "%s", name); | |
147 | atomic_set(&dev->refcnt, 0); | |
148 | INIT_LIST_HEAD(&dev->queue_list); | |
149 | spin_lock_init(&dev->queue_lock); | |
150 | ||
151 | dev->nls = nls; | |
7672d0b5 | 152 | |
6cebb17b TH |
153 | dev->cn_queue = alloc_ordered_workqueue(dev->name, 0); |
154 | if (!dev->cn_queue) { | |
155 | kfree(dev); | |
156 | return NULL; | |
157 | } | |
7672d0b5 EP |
158 | |
159 | return dev; | |
160 | } | |
161 | ||
162 | void cn_queue_free_dev(struct cn_queue_dev *dev) | |
163 | { | |
164 | struct cn_callback_entry *cbq, *n; | |
165 | ||
6cebb17b TH |
166 | flush_workqueue(dev->cn_queue); |
167 | destroy_workqueue(dev->cn_queue); | |
7672d0b5 EP |
168 | |
169 | spin_lock_bh(&dev->queue_lock); | |
170 | list_for_each_entry_safe(cbq, n, &dev->queue_list, callback_entry) | |
171 | list_del(&cbq->callback_entry); | |
172 | spin_unlock_bh(&dev->queue_lock); | |
173 | ||
174 | while (atomic_read(&dev->refcnt)) { | |
175 | printk(KERN_INFO "Waiting for %s to become free: refcnt=%d.\n", | |
176 | dev->name, atomic_read(&dev->refcnt)); | |
177 | msleep(1000); | |
178 | } | |
179 | ||
180 | kfree(dev); | |
181 | dev = NULL; | |
182 | } |