[PATCH] sysctl: move SYSV IPC sysctls to their own file
[linux-2.6.git] / ipc / ipc_sysctl.c
1 /*
2  *  Copyright (C) 2007
3  *
4  *  Author: Eric Biederman <ebiederm@xmision.com>
5  *
6  *  This program is free software; you can redistribute it and/or
7  *  modify it under the terms of the GNU General Public License as
8  *  published by the Free Software Foundation, version 2 of the
9  *  License.
10  */
11
12 #include <linux/module.h>
13 #include <linux/ipc.h>
14 #include <linux/nsproxy.h>
15 #include <linux/sysctl.h>
16 #include <linux/uaccess.h>
17
18 #ifdef CONFIG_IPC_NS
19 static void *get_ipc(ctl_table *table)
20 {
21         char *which = table->data;
22         struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
23         which = (which - (char *)&init_ipc_ns) + (char *)ipc_ns;
24         return which;
25 }
26 #else
27 #define get_ipc(T) ((T)->data)
28 #endif
29
30 #ifdef CONFIG_PROC_FS
31 static int proc_ipc_dointvec(ctl_table *table, int write, struct file *filp,
32         void __user *buffer, size_t *lenp, loff_t *ppos)
33 {
34         struct ctl_table ipc_table;
35         memcpy(&ipc_table, table, sizeof(ipc_table));
36         ipc_table.data = get_ipc(table);
37
38         return proc_dointvec(&ipc_table, write, filp, buffer, lenp, ppos);
39 }
40
41 static int proc_ipc_doulongvec_minmax(ctl_table *table, int write,
42         struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos)
43 {
44         struct ctl_table ipc_table;
45         memcpy(&ipc_table, table, sizeof(ipc_table));
46         ipc_table.data = get_ipc(table);
47
48         return proc_doulongvec_minmax(&ipc_table, write, filp, buffer,
49                                         lenp, ppos);
50 }
51
52 #else
53 #define proc_ipc_doulongvec_minmax NULL
54 #define proc_ipc_dointvec          NULL
55 #endif
56
57 #ifdef CONFIG_SYSCTL_SYSCALL
58 /* The generic sysctl ipc data routine. */
59 static int sysctl_ipc_data(ctl_table *table, int __user *name, int nlen,
60                 void __user *oldval, size_t __user *oldlenp,
61                 void __user *newval, size_t newlen)
62 {
63         size_t len;
64         void *data;
65
66         /* Get out of I don't have a variable */
67         if (!table->data || !table->maxlen)
68                 return -ENOTDIR;
69
70         data = get_ipc(table);
71         if (!data)
72                 return -ENOTDIR;
73
74         if (oldval && oldlenp) {
75                 if (get_user(len, oldlenp))
76                         return -EFAULT;
77                 if (len) {
78                         if (len > table->maxlen)
79                                 len = table->maxlen;
80                         if (copy_to_user(oldval, data, len))
81                                 return -EFAULT;
82                         if (put_user(len, oldlenp))
83                                 return -EFAULT;
84                 }
85         }
86
87         if (newval && newlen) {
88                 if (newlen > table->maxlen)
89                         newlen = table->maxlen;
90
91                 if (copy_from_user(data, newval, newlen))
92                         return -EFAULT;
93         }
94         return 1;
95 }
96 #else
97 #define sysctl_ipc_data NULL
98 #endif
99
100 static struct ctl_table ipc_kern_table[] = {
101         {
102                 .ctl_name       = KERN_SHMMAX,
103                 .procname       = "shmmax",
104                 .data           = &init_ipc_ns.shm_ctlmax,
105                 .maxlen         = sizeof (init_ipc_ns.shm_ctlmax),
106                 .mode           = 0644,
107                 .proc_handler   = proc_ipc_doulongvec_minmax,
108                 .strategy       = sysctl_ipc_data,
109         },
110         {
111                 .ctl_name       = KERN_SHMALL,
112                 .procname       = "shmall",
113                 .data           = &init_ipc_ns.shm_ctlall,
114                 .maxlen         = sizeof (init_ipc_ns.shm_ctlall),
115                 .mode           = 0644,
116                 .proc_handler   = proc_ipc_doulongvec_minmax,
117                 .strategy       = sysctl_ipc_data,
118         },
119         {
120                 .ctl_name       = KERN_SHMMNI,
121                 .procname       = "shmmni",
122                 .data           = &init_ipc_ns.shm_ctlmni,
123                 .maxlen         = sizeof (init_ipc_ns.shm_ctlmni),
124                 .mode           = 0644,
125                 .proc_handler   = proc_ipc_dointvec,
126                 .strategy       = sysctl_ipc_data,
127         },
128         {
129                 .ctl_name       = KERN_MSGMAX,
130                 .procname       = "msgmax",
131                 .data           = &init_ipc_ns.msg_ctlmax,
132                 .maxlen         = sizeof (init_ipc_ns.msg_ctlmax),
133                 .mode           = 0644,
134                 .proc_handler   = proc_ipc_dointvec,
135                 .strategy       = sysctl_ipc_data,
136         },
137         {
138                 .ctl_name       = KERN_MSGMNI,
139                 .procname       = "msgmni",
140                 .data           = &init_ipc_ns.msg_ctlmni,
141                 .maxlen         = sizeof (init_ipc_ns.msg_ctlmni),
142                 .mode           = 0644,
143                 .proc_handler   = proc_ipc_dointvec,
144                 .strategy       = sysctl_ipc_data,
145         },
146         {
147                 .ctl_name       = KERN_MSGMNB,
148                 .procname       =  "msgmnb",
149                 .data           = &init_ipc_ns.msg_ctlmnb,
150                 .maxlen         = sizeof (init_ipc_ns.msg_ctlmnb),
151                 .mode           = 0644,
152                 .proc_handler   = proc_ipc_dointvec,
153                 .strategy       = sysctl_ipc_data,
154         },
155         {
156                 .ctl_name       = KERN_SEM,
157                 .procname       = "sem",
158                 .data           = &init_ipc_ns.sem_ctls,
159                 .maxlen         = 4*sizeof (int),
160                 .mode           = 0644,
161                 .proc_handler   = proc_ipc_dointvec,
162                 .strategy       = sysctl_ipc_data,
163         },
164         {}
165 };
166
167 static struct ctl_table ipc_root_table[] = {
168         {
169                 .ctl_name       = CTL_KERN,
170                 .procname       = "kernel",
171                 .mode           = 0555,
172                 .child          = ipc_kern_table,
173         },
174         {}
175 };
176
177 static int __init ipc_sysctl_init(void)
178 {
179         register_sysctl_table(ipc_root_table, 0);
180         return 0;
181 }
182
183 __initcall(ipc_sysctl_init);