Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * sysctl.h: General linux system control interface | |
3 | * | |
4 | * Begun 24 March 1995, Stephen Tweedie | |
5 | * | |
6 | **************************************************************** | |
7 | **************************************************************** | |
8 | ** | |
7cc13edc | 9 | ** WARNING: |
1da177e4 | 10 | ** The values in this file are exported to user space via |
7cc13edc EB |
11 | ** the sysctl() binary interface. Do *NOT* change the |
12 | ** numbering of any existing values here, and do not change | |
13 | ** any numbers within any one set of values. If you have to | |
93aec204 | 14 | ** redefine an existing interface, use a new number for it. |
7cc13edc EB |
15 | ** The kernel will then return -ENOTDIR to any application using |
16 | ** the old binary interface. | |
17 | ** | |
1da177e4 LT |
18 | **************************************************************** |
19 | **************************************************************** | |
20 | */ | |
1da177e4 LT |
21 | #ifndef _LINUX_SYSCTL_H |
22 | #define _LINUX_SYSCTL_H | |
23 | ||
d4ed803c | 24 | #include <linux/list.h> |
684adca4 | 25 | #include <linux/rcupdate.h> |
f1ecf068 | 26 | #include <linux/wait.h> |
ac13ac6f | 27 | #include <linux/rbtree.h> |
607ca46e | 28 | #include <uapi/linux/sysctl.h> |
1da177e4 | 29 | |
805b5d5e | 30 | /* For the /proc/sys support */ |
db3f6001 | 31 | struct completion; |
1ff007eb | 32 | struct ctl_table; |
e51b6ba0 | 33 | struct nsproxy; |
d7321cd6 | 34 | struct ctl_table_root; |
f7e6ced4 | 35 | struct ctl_table_header; |
7ec66d06 | 36 | struct ctl_dir; |
f7e6ced4 | 37 | |
8d65af78 | 38 | typedef int proc_handler (struct ctl_table *ctl, int write, |
1da177e4 LT |
39 | void __user *buffer, size_t *lenp, loff_t *ppos); |
40 | ||
8d65af78 | 41 | extern int proc_dostring(struct ctl_table *, int, |
1da177e4 | 42 | void __user *, size_t *, loff_t *); |
8d65af78 | 43 | extern int proc_dointvec(struct ctl_table *, int, |
1da177e4 | 44 | void __user *, size_t *, loff_t *); |
e7d316a0 SAK |
45 | extern int proc_douintvec(struct ctl_table *, int, |
46 | void __user *, size_t *, loff_t *); | |
8d65af78 | 47 | extern int proc_dointvec_minmax(struct ctl_table *, int, |
1da177e4 | 48 | void __user *, size_t *, loff_t *); |
8d65af78 | 49 | extern int proc_dointvec_jiffies(struct ctl_table *, int, |
1da177e4 | 50 | void __user *, size_t *, loff_t *); |
8d65af78 | 51 | extern int proc_dointvec_userhz_jiffies(struct ctl_table *, int, |
1da177e4 | 52 | void __user *, size_t *, loff_t *); |
8d65af78 | 53 | extern int proc_dointvec_ms_jiffies(struct ctl_table *, int, |
1da177e4 | 54 | void __user *, size_t *, loff_t *); |
8d65af78 | 55 | extern int proc_doulongvec_minmax(struct ctl_table *, int, |
1da177e4 | 56 | void __user *, size_t *, loff_t *); |
d8217f07 | 57 | extern int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int, |
8d65af78 | 58 | void __user *, size_t *, loff_t *); |
9f977fb7 OP |
59 | extern int proc_do_large_bitmap(struct ctl_table *, int, |
60 | void __user *, size_t *, loff_t *); | |
1da177e4 | 61 | |
1da177e4 LT |
62 | /* |
63 | * Register a set of sysctl names by calling register_sysctl_table | |
2315ffa0 EB |
64 | * with an initialised array of struct ctl_table's. An entry with |
65 | * NULL procname terminates the table. table->de will be | |
d99f160a | 66 | * set up by the registration and need not be initialised in advance. |
1da177e4 LT |
67 | * |
68 | * sysctl names can be mirrored automatically under /proc/sys. The | |
69 | * procname supplied controls /proc naming. | |
70 | * | |
71 | * The table's mode will be honoured both for sys_sysctl(2) and | |
72 | * proc-fs access. | |
73 | * | |
74 | * Leaf nodes in the sysctl tree will be represented by a single file | |
75 | * under /proc; non-leaf nodes will be represented by directories. A | |
76 | * null procname disables /proc mirroring at this node. | |
d99f160a | 77 | * |
1da177e4 LT |
78 | * sysctl(2) can automatically manage read and write requests through |
79 | * the sysctl table. The data and maxlen fields of the ctl_table | |
80 | * struct enable minimal validation of the values being written to be | |
81 | * performed, and the mode field allows minimal authentication. | |
82 | * | |
1da177e4 LT |
83 | * There must be a proc_handler routine for any terminal nodes |
84 | * mirrored under /proc/sys (non-terminals are handled by a built-in | |
85 | * directory handler). Several default handlers are available to | |
86 | * cover common cases. | |
87 | */ | |
88 | ||
f1ecf068 LDM |
89 | /* Support for userspace poll() to watch for changes */ |
90 | struct ctl_table_poll { | |
91 | atomic_t event; | |
92 | wait_queue_head_t wait; | |
93 | }; | |
94 | ||
95 | static inline void *proc_sys_poll_event(struct ctl_table_poll *poll) | |
96 | { | |
97 | return (void *)(unsigned long)atomic_read(&poll->event); | |
98 | } | |
99 | ||
f1ecf068 LDM |
100 | #define __CTL_TABLE_POLL_INITIALIZER(name) { \ |
101 | .event = ATOMIC_INIT(0), \ | |
102 | .wait = __WAIT_QUEUE_HEAD_INITIALIZER(name.wait) } | |
103 | ||
104 | #define DEFINE_CTL_TABLE_POLL(name) \ | |
105 | struct ctl_table_poll name = __CTL_TABLE_POLL_INITIALIZER(name) | |
106 | ||
1da177e4 LT |
107 | /* A sysctl table is an array of struct ctl_table: */ |
108 | struct ctl_table | |
109 | { | |
1da177e4 LT |
110 | const char *procname; /* Text ID for /proc/sys, or zero */ |
111 | void *data; | |
112 | int maxlen; | |
36fcb589 | 113 | umode_t mode; |
f728019b | 114 | struct ctl_table *child; /* Deprecated */ |
1da177e4 | 115 | proc_handler *proc_handler; /* Callback for text formatting */ |
f1ecf068 | 116 | struct ctl_table_poll *poll; |
1da177e4 LT |
117 | void *extra1; |
118 | void *extra2; | |
119 | }; | |
120 | ||
ac13ac6f EB |
121 | struct ctl_node { |
122 | struct rb_node node; | |
123 | struct ctl_table_header *header; | |
124 | }; | |
125 | ||
1da177e4 | 126 | /* struct ctl_table_header is used to maintain dynamic lists of |
d8217f07 | 127 | struct ctl_table trees. */ |
1da177e4 LT |
128 | struct ctl_table_header |
129 | { | |
dfef6dcd AV |
130 | union { |
131 | struct { | |
132 | struct ctl_table *ctl_table; | |
dfef6dcd AV |
133 | int used; |
134 | int count; | |
938aaa4f | 135 | int nreg; |
dfef6dcd AV |
136 | }; |
137 | struct rcu_head rcu; | |
138 | }; | |
330d57fb | 139 | struct completion *unregistering; |
23eb06de | 140 | struct ctl_table *ctl_table_arg; |
e51b6ba0 | 141 | struct ctl_table_root *root; |
73455092 | 142 | struct ctl_table_set *set; |
7ec66d06 | 143 | struct ctl_dir *parent; |
ac13ac6f | 144 | struct ctl_node *node; |
7ec66d06 EB |
145 | }; |
146 | ||
147 | struct ctl_dir { | |
148 | /* Header must be at the start of ctl_dir */ | |
149 | struct ctl_table_header header; | |
ac13ac6f | 150 | struct rb_root root; |
1da177e4 LT |
151 | }; |
152 | ||
0ce8974d | 153 | struct ctl_table_set { |
0ce8974d | 154 | int (*is_seen)(struct ctl_table_set *); |
0e47c99d | 155 | struct ctl_dir dir; |
0ce8974d EB |
156 | }; |
157 | ||
158 | struct ctl_table_root { | |
0ce8974d EB |
159 | struct ctl_table_set default_set; |
160 | struct ctl_table_set *(*lookup)(struct ctl_table_root *root, | |
161 | struct nsproxy *namespaces); | |
73f7ef43 | 162 | int (*permissions)(struct ctl_table_header *head, struct ctl_table *table); |
0ce8974d EB |
163 | }; |
164 | ||
29e796fd EB |
165 | /* struct ctl_path describes where in the hierarchy a table is added */ |
166 | struct ctl_path { | |
167 | const char *procname; | |
29e796fd EB |
168 | }; |
169 | ||
0ce8974d EB |
170 | #ifdef CONFIG_SYSCTL |
171 | ||
172 | void proc_sys_poll_notify(struct ctl_table_poll *poll); | |
173 | ||
174 | extern void setup_sysctl_set(struct ctl_table_set *p, | |
9eb47c26 | 175 | struct ctl_table_root *root, |
0ce8974d | 176 | int (*is_seen)(struct ctl_table_set *)); |
97324cd8 | 177 | extern void retire_sysctl_set(struct ctl_table_set *set); |
0ce8974d | 178 | |
e51b6ba0 | 179 | void register_sysctl_root(struct ctl_table_root *root); |
6e9d5164 | 180 | struct ctl_table_header *__register_sysctl_table( |
60a47a2e | 181 | struct ctl_table_set *set, |
6e9d5164 | 182 | const char *path, struct ctl_table *table); |
e51b6ba0 | 183 | struct ctl_table_header *__register_sysctl_paths( |
60a47a2e | 184 | struct ctl_table_set *set, |
e51b6ba0 | 185 | const struct ctl_path *path, struct ctl_table *table); |
fea478d4 | 186 | struct ctl_table_header *register_sysctl(const char *path, struct ctl_table *table); |
d8217f07 | 187 | struct ctl_table_header *register_sysctl_table(struct ctl_table * table); |
29e796fd EB |
188 | struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path, |
189 | struct ctl_table *table); | |
0b4d4147 | 190 | |
1da177e4 LT |
191 | void unregister_sysctl_table(struct ctl_table_header * table); |
192 | ||
de4e83bd | 193 | extern int sysctl_init(void); |
f9bd6733 EB |
194 | |
195 | extern struct ctl_table sysctl_mount_point[]; | |
196 | ||
0ce8974d EB |
197 | #else /* CONFIG_SYSCTL */ |
198 | static inline struct ctl_table_header *register_sysctl_table(struct ctl_table * table) | |
199 | { | |
200 | return NULL; | |
201 | } | |
202 | ||
203 | static inline struct ctl_table_header *register_sysctl_paths( | |
204 | const struct ctl_path *path, struct ctl_table *table) | |
205 | { | |
206 | return NULL; | |
207 | } | |
208 | ||
209 | static inline void unregister_sysctl_table(struct ctl_table_header * table) | |
210 | { | |
211 | } | |
212 | ||
213 | static inline void setup_sysctl_set(struct ctl_table_set *p, | |
9eb47c26 | 214 | struct ctl_table_root *root, |
0ce8974d EB |
215 | int (*is_seen)(struct ctl_table_set *)) |
216 | { | |
217 | } | |
218 | ||
0ce8974d EB |
219 | #endif /* CONFIG_SYSCTL */ |
220 | ||
16db3d3f HS |
221 | int sysctl_max_threads(struct ctl_table *table, int write, |
222 | void __user *buffer, size_t *lenp, loff_t *ppos); | |
223 | ||
1da177e4 | 224 | #endif /* _LINUX_SYSCTL_H */ |