Commit | Line | Data |
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1a59d1b8 | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
7672d0b5 | 2 | /* |
f3c48ecc | 3 | * cn_queue.c |
1a5645bc | 4 | * |
acb9c1b2 | 5 | * 2004+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net> |
7672d0b5 | 6 | * All rights reserved. |
7672d0b5 EP |
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 | ||
0741241c | 20 | static struct cn_callback_entry * |
04f482fa | 21 | cn_queue_alloc_callback_entry(struct cn_queue_dev *dev, const char *name, |
c18e6869 | 22 | const struct cb_id *id, |
f3c48ecc VI |
23 | void (*callback)(struct cn_msg *, |
24 | struct netlink_skb_parms *)) | |
7672d0b5 EP |
25 | { |
26 | struct cn_callback_entry *cbq; | |
27 | ||
28 | cbq = kzalloc(sizeof(*cbq), GFP_KERNEL); | |
29 | if (!cbq) { | |
f3c48ecc | 30 | pr_err("Failed to create new callback queue.\n"); |
7672d0b5 EP |
31 | return NULL; |
32 | } | |
33 | ||
e65f7ee3 | 34 | refcount_set(&cbq->refcnt, 1); |
04f482fa PM |
35 | |
36 | atomic_inc(&dev->refcnt); | |
37 | cbq->pdev = dev; | |
38 | ||
acd042bb EP |
39 | snprintf(cbq->id.name, sizeof(cbq->id.name), "%s", name); |
40 | memcpy(&cbq->id.id, id, sizeof(struct cb_id)); | |
04f482fa | 41 | cbq->callback = callback; |
7672d0b5 EP |
42 | return cbq; |
43 | } | |
44 | ||
04f482fa | 45 | void cn_queue_release_callback(struct cn_callback_entry *cbq) |
7672d0b5 | 46 | { |
e65f7ee3 | 47 | if (!refcount_dec_and_test(&cbq->refcnt)) |
04f482fa PM |
48 | return; |
49 | ||
50 | atomic_dec(&cbq->pdev->refcnt); | |
7672d0b5 EP |
51 | kfree(cbq); |
52 | } | |
53 | ||
c18e6869 | 54 | int cn_cb_equal(const struct cb_id *i1, const struct cb_id *i2) |
7672d0b5 EP |
55 | { |
56 | return ((i1->idx == i2->idx) && (i1->val == i2->val)); | |
57 | } | |
58 | ||
008536e8 | 59 | int cn_queue_add_callback(struct cn_queue_dev *dev, const char *name, |
c18e6869 | 60 | const struct cb_id *id, |
f3c48ecc VI |
61 | void (*callback)(struct cn_msg *, |
62 | struct netlink_skb_parms *)) | |
7672d0b5 EP |
63 | { |
64 | struct cn_callback_entry *cbq, *__cbq; | |
65 | int found = 0; | |
66 | ||
04f482fa | 67 | cbq = cn_queue_alloc_callback_entry(dev, name, id, callback); |
7672d0b5 EP |
68 | if (!cbq) |
69 | return -ENOMEM; | |
70 | ||
7672d0b5 EP |
71 | spin_lock_bh(&dev->queue_lock); |
72 | list_for_each_entry(__cbq, &dev->queue_list, callback_entry) { | |
acd042bb | 73 | if (cn_cb_equal(&__cbq->id.id, id)) { |
7672d0b5 EP |
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) { | |
04f482fa | 83 | cn_queue_release_callback(cbq); |
7672d0b5 EP |
84 | return -EINVAL; |
85 | } | |
86 | ||
7672d0b5 | 87 | cbq->seq = 0; |
acd042bb | 88 | cbq->group = cbq->id.id.idx; |
7672d0b5 EP |
89 | |
90 | return 0; | |
91 | } | |
92 | ||
c18e6869 | 93 | void cn_queue_del_callback(struct cn_queue_dev *dev, const struct cb_id *id) |
7672d0b5 EP |
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) { | |
acd042bb | 100 | if (cn_cb_equal(&cbq->id.id, id)) { |
7672d0b5 EP |
101 | list_del(&cbq->callback_entry); |
102 | found = 1; | |
103 | break; | |
104 | } | |
105 | } | |
106 | spin_unlock_bh(&dev->queue_lock); | |
107 | ||
04f482fa PM |
108 | if (found) |
109 | cn_queue_release_callback(cbq); | |
7672d0b5 EP |
110 | } |
111 | ||
008536e8 | 112 | struct cn_queue_dev *cn_queue_alloc_dev(const char *name, struct sock *nls) |
7672d0b5 EP |
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; | |
7672d0b5 | 126 | |
7672d0b5 EP |
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 | ||
7672d0b5 EP |
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)) { | |
f3c48ecc | 140 | pr_info("Waiting for %s to become free: refcnt=%d.\n", |
7672d0b5 EP |
141 | dev->name, atomic_read(&dev->refcnt)); |
142 | msleep(1000); | |
143 | } | |
144 | ||
145 | kfree(dev); | |
146 | dev = NULL; | |
147 | } |