]>
Commit | Line | Data |
---|---|---|
b9c15df9 PS |
1 | /* |
2 | * Copyright (c) 2007-2012 Nicira Networks. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of version 2 of the GNU General Public | |
6 | * License as published by the Free Software Foundation. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, but | |
9 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
11 | * General Public License for more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public License | |
14 | * along with this program; if not, write to the Free Software | |
15 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA | |
16 | * 02110-1301, USA | |
17 | */ | |
18 | ||
19 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt | |
20 | ||
21 | #include <linux/version.h> | |
22 | #include <net/genetlink.h> | |
23 | #include "genl_exec.h" | |
24 | ||
25 | #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,35) | |
26 | ||
27 | static DEFINE_MUTEX(genl_exec_lock); | |
28 | ||
29 | static genl_exec_func_t genl_exec_function; | |
30 | static int genl_exec_function_ret; | |
31 | static void *genl_exec_data; | |
32 | static struct completion done; | |
33 | ||
34 | static struct sk_buff *genlmsg_skb; | |
35 | ||
36 | static int genl_exec_cmd(struct sk_buff *dummy, struct genl_info *dummy2) | |
37 | { | |
38 | genl_exec_function_ret = genl_exec_function(genl_exec_data); | |
39 | complete(&done); | |
40 | return 0; | |
41 | } | |
42 | ||
43 | enum exec_cmd { | |
44 | GENL_EXEC_UNSPEC, | |
45 | GENL_EXEC_RUN, | |
46 | }; | |
47 | ||
48 | static struct genl_family genl_exec_family = { | |
49 | .id = GENL_ID_GENERATE, | |
50 | .name = "ovs_genl_exec", | |
51 | .version = 1, | |
52 | }; | |
53 | ||
54 | static struct genl_ops genl_exec_ops[] = { | |
55 | { | |
56 | .cmd = GENL_EXEC_RUN, | |
57 | .doit = genl_exec_cmd, | |
58 | .flags = CAP_NET_ADMIN, | |
59 | }, | |
60 | }; | |
61 | ||
62 | int genl_exec_init(void) | |
63 | { | |
64 | int err; | |
65 | ||
66 | err = genl_register_family_with_ops(&genl_exec_family, | |
67 | genl_exec_ops, ARRAY_SIZE(genl_exec_ops)); | |
68 | ||
69 | if (err) | |
70 | return err; | |
71 | ||
72 | genlmsg_skb = genlmsg_new(0, GFP_KERNEL); | |
73 | if (!genlmsg_skb) { | |
74 | genl_unregister_family(&genl_exec_family); | |
75 | return -ENOMEM; | |
76 | } | |
77 | return 0; | |
78 | } | |
79 | ||
80 | void genl_exec_exit(void) | |
81 | { | |
82 | kfree_skb(genlmsg_skb); | |
83 | genl_unregister_family(&genl_exec_family); | |
84 | } | |
85 | ||
86 | /* genl_lock() is not exported from older kernel. | |
87 | * Following function allows any function to be executed with | |
88 | * genl_mutex held. */ | |
89 | ||
90 | int genl_exec(genl_exec_func_t func, void *data) | |
91 | { | |
92 | int ret; | |
93 | ||
94 | mutex_lock(&genl_exec_lock); | |
95 | ||
96 | init_completion(&done); | |
97 | skb_get(genlmsg_skb); | |
98 | genlmsg_put(genlmsg_skb, 0, 0, &genl_exec_family, | |
99 | NLM_F_REQUEST, GENL_EXEC_RUN); | |
100 | ||
101 | genl_exec_function = func; | |
102 | genl_exec_data = data; | |
103 | ret = genlmsg_unicast(&init_net, genlmsg_skb, 0); | |
104 | ||
105 | if (!ret) { | |
106 | wait_for_completion(&done); | |
107 | ret = genl_exec_function_ret; | |
108 | } else { | |
109 | pr_err("genl_exec send error %d\n", ret); | |
110 | } | |
111 | ||
112 | /* Wait for genetlink to kfree skb. */ | |
113 | while (skb_shared(genlmsg_skb)) | |
114 | cpu_relax(); | |
115 | ||
116 | genlmsg_skb->data = genlmsg_skb->head; | |
117 | skb_reset_tail_pointer(genlmsg_skb); | |
118 | ||
119 | mutex_unlock(&genl_exec_lock); | |
120 | ||
121 | return ret; | |
122 | } | |
123 | ||
124 | #else | |
125 | ||
126 | int genl_exec(genl_exec_func_t func, void *data) | |
127 | { | |
128 | int ret; | |
129 | ||
130 | genl_lock(); | |
131 | ret = func(data); | |
132 | genl_unlock(); | |
133 | return ret; | |
134 | } | |
135 | ||
136 | int genl_exec_init(void) | |
137 | { | |
138 | return 0; | |
139 | } | |
140 | ||
141 | void genl_exec_exit(void) | |
142 | { | |
143 | } | |
144 | #endif |