295 lines
9.6 KiB
C
295 lines
9.6 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* sysctl.h: General linux system control interface
|
|
*
|
|
* Begun 24 March 1995, Stephen Tweedie
|
|
*
|
|
****************************************************************
|
|
****************************************************************
|
|
**
|
|
** WARNING:
|
|
** The values in this file are exported to user space via
|
|
** the sysctl() binary interface. Do *NOT* change the
|
|
** numbering of any existing values here, and do not change
|
|
** any numbers within any one set of values. If you have to
|
|
** redefine an existing interface, use a new number for it.
|
|
** The kernel will then return -ENOTDIR to any application using
|
|
** the old binary interface.
|
|
**
|
|
****************************************************************
|
|
****************************************************************
|
|
*/
|
|
#ifndef _LINUX_SYSCTL_H
|
|
#define _LINUX_SYSCTL_H
|
|
|
|
#include <linux/list.h>
|
|
#include <linux/rcupdate.h>
|
|
#include <linux/wait.h>
|
|
#include <linux/rbtree.h>
|
|
#include <linux/uidgid.h>
|
|
#include <uapi/linux/sysctl.h>
|
|
|
|
/* For the /proc/sys support */
|
|
struct completion;
|
|
struct ctl_table;
|
|
struct nsproxy;
|
|
struct ctl_table_root;
|
|
struct ctl_table_header;
|
|
struct ctl_dir;
|
|
|
|
/* Keep the same order as in fs/proc/proc_sysctl.c */
|
|
#define SYSCTL_ZERO ((void *)&sysctl_vals[0])
|
|
#define SYSCTL_ONE ((void *)&sysctl_vals[1])
|
|
#define SYSCTL_TWO ((void *)&sysctl_vals[2])
|
|
#define SYSCTL_THREE ((void *)&sysctl_vals[3])
|
|
#define SYSCTL_FOUR ((void *)&sysctl_vals[4])
|
|
#define SYSCTL_ONE_HUNDRED ((void *)&sysctl_vals[5])
|
|
#define SYSCTL_TWO_HUNDRED ((void *)&sysctl_vals[6])
|
|
#define SYSCTL_ONE_THOUSAND ((void *)&sysctl_vals[7])
|
|
#define SYSCTL_THREE_THOUSAND ((void *)&sysctl_vals[8])
|
|
#define SYSCTL_INT_MAX ((void *)&sysctl_vals[9])
|
|
|
|
/* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
|
|
#define SYSCTL_MAXOLDUID ((void *)&sysctl_vals[10])
|
|
#define SYSCTL_NEG_ONE ((void *)&sysctl_vals[11])
|
|
|
|
extern const int sysctl_vals[];
|
|
|
|
#define SYSCTL_LONG_ZERO ((void *)&sysctl_long_vals[0])
|
|
#define SYSCTL_LONG_ONE ((void *)&sysctl_long_vals[1])
|
|
#define SYSCTL_LONG_MAX ((void *)&sysctl_long_vals[2])
|
|
|
|
extern const unsigned long sysctl_long_vals[];
|
|
|
|
typedef int proc_handler(struct ctl_table *ctl, int write, void *buffer,
|
|
size_t *lenp, loff_t *ppos);
|
|
|
|
int proc_dostring(struct ctl_table *, int, void *, size_t *, loff_t *);
|
|
int proc_dobool(struct ctl_table *table, int write, void *buffer,
|
|
size_t *lenp, loff_t *ppos);
|
|
int proc_dointvec(struct ctl_table *, int, void *, size_t *, loff_t *);
|
|
int proc_douintvec(struct ctl_table *, int, void *, size_t *, loff_t *);
|
|
int proc_dointvec_minmax(struct ctl_table *, int, void *, size_t *, loff_t *);
|
|
int proc_douintvec_minmax(struct ctl_table *table, int write, void *buffer,
|
|
size_t *lenp, loff_t *ppos);
|
|
int proc_dou8vec_minmax(struct ctl_table *table, int write, void *buffer,
|
|
size_t *lenp, loff_t *ppos);
|
|
int proc_dointvec_jiffies(struct ctl_table *, int, void *, size_t *, loff_t *);
|
|
int proc_dointvec_ms_jiffies_minmax(struct ctl_table *table, int write,
|
|
void *buffer, size_t *lenp, loff_t *ppos);
|
|
int proc_dointvec_userhz_jiffies(struct ctl_table *, int, void *, size_t *,
|
|
loff_t *);
|
|
int proc_dointvec_ms_jiffies(struct ctl_table *, int, void *, size_t *,
|
|
loff_t *);
|
|
int proc_doulongvec_minmax(struct ctl_table *, int, void *, size_t *, loff_t *);
|
|
int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int, void *,
|
|
size_t *, loff_t *);
|
|
int proc_do_large_bitmap(struct ctl_table *, int, void *, size_t *, loff_t *);
|
|
int proc_do_static_key(struct ctl_table *table, int write, void *buffer,
|
|
size_t *lenp, loff_t *ppos);
|
|
|
|
/*
|
|
* Register a set of sysctl names by calling register_sysctl
|
|
* with an initialised array of struct ctl_table's. An entry with
|
|
* NULL procname terminates the table. table->de will be
|
|
* set up by the registration and need not be initialised in advance.
|
|
*
|
|
* sysctl names can be mirrored automatically under /proc/sys. The
|
|
* procname supplied controls /proc naming.
|
|
*
|
|
* The table's mode will be honoured for proc-fs access.
|
|
*
|
|
* Leaf nodes in the sysctl tree will be represented by a single file
|
|
* under /proc; non-leaf nodes will be represented by directories. A
|
|
* null procname disables /proc mirroring at this node.
|
|
*
|
|
* The data and maxlen fields of the ctl_table
|
|
* struct enable minimal validation of the values being written to be
|
|
* performed, and the mode field allows minimal authentication.
|
|
*
|
|
* There must be a proc_handler routine for any terminal nodes
|
|
* mirrored under /proc/sys (non-terminals are handled by a built-in
|
|
* directory handler). Several default handlers are available to
|
|
* cover common cases.
|
|
*/
|
|
|
|
/* Support for userspace poll() to watch for changes */
|
|
struct ctl_table_poll {
|
|
atomic_t event;
|
|
wait_queue_head_t wait;
|
|
};
|
|
|
|
static inline void *proc_sys_poll_event(struct ctl_table_poll *poll)
|
|
{
|
|
return (void *)(unsigned long)atomic_read(&poll->event);
|
|
}
|
|
|
|
#define __CTL_TABLE_POLL_INITIALIZER(name) { \
|
|
.event = ATOMIC_INIT(0), \
|
|
.wait = __WAIT_QUEUE_HEAD_INITIALIZER(name.wait) }
|
|
|
|
#define DEFINE_CTL_TABLE_POLL(name) \
|
|
struct ctl_table_poll name = __CTL_TABLE_POLL_INITIALIZER(name)
|
|
|
|
/* A sysctl table is an array of struct ctl_table: */
|
|
struct ctl_table {
|
|
const char *procname; /* Text ID for /proc/sys, or zero */
|
|
void *data;
|
|
int maxlen;
|
|
umode_t mode;
|
|
/**
|
|
* enum type - Enumeration to differentiate between ctl target types
|
|
* @SYSCTL_TABLE_TYPE_DEFAULT: ctl target with no special considerations
|
|
* @SYSCTL_TABLE_TYPE_PERMANENTLY_EMPTY: Used to identify a permanently
|
|
* empty directory target to serve
|
|
* as mount point.
|
|
*/
|
|
enum {
|
|
SYSCTL_TABLE_TYPE_DEFAULT,
|
|
SYSCTL_TABLE_TYPE_PERMANENTLY_EMPTY
|
|
} type;
|
|
proc_handler *proc_handler; /* Callback for text formatting */
|
|
struct ctl_table_poll *poll;
|
|
void *extra1;
|
|
void *extra2;
|
|
} __randomize_layout;
|
|
|
|
struct ctl_node {
|
|
struct rb_node node;
|
|
struct ctl_table_header *header;
|
|
};
|
|
|
|
/**
|
|
* struct ctl_table_header - maintains dynamic lists of struct ctl_table trees
|
|
* @ctl_table: pointer to the first element in ctl_table array
|
|
* @ctl_table_size: number of elements pointed by @ctl_table
|
|
* @used: The entry will never be touched when equal to 0.
|
|
* @count: Upped every time something is added to @inodes and downed every time
|
|
* something is removed from inodes
|
|
* @nreg: When nreg drops to 0 the ctl_table_header will be unregistered.
|
|
* @rcu: Delays the freeing of the inode. Introduced with "unfuck proc_sysctl ->d_compare()"
|
|
*
|
|
*/
|
|
struct ctl_table_header {
|
|
union {
|
|
struct {
|
|
struct ctl_table *ctl_table;
|
|
int ctl_table_size;
|
|
int used;
|
|
int count;
|
|
int nreg;
|
|
};
|
|
struct rcu_head rcu;
|
|
};
|
|
struct completion *unregistering;
|
|
struct ctl_table *ctl_table_arg;
|
|
struct ctl_table_root *root;
|
|
struct ctl_table_set *set;
|
|
struct ctl_dir *parent;
|
|
struct ctl_node *node;
|
|
struct hlist_head inodes; /* head for proc_inode->sysctl_inodes */
|
|
};
|
|
|
|
struct ctl_dir {
|
|
/* Header must be at the start of ctl_dir */
|
|
struct ctl_table_header header;
|
|
struct rb_root root;
|
|
};
|
|
|
|
struct ctl_table_set {
|
|
int (*is_seen)(struct ctl_table_set *);
|
|
struct ctl_dir dir;
|
|
};
|
|
|
|
struct ctl_table_root {
|
|
struct ctl_table_set default_set;
|
|
struct ctl_table_set *(*lookup)(struct ctl_table_root *root);
|
|
void (*set_ownership)(struct ctl_table_header *head,
|
|
struct ctl_table *table,
|
|
kuid_t *uid, kgid_t *gid);
|
|
int (*permissions)(struct ctl_table_header *head, struct ctl_table *table);
|
|
};
|
|
|
|
#define register_sysctl(path, table) \
|
|
register_sysctl_sz(path, table, ARRAY_SIZE(table))
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
|
|
void proc_sys_poll_notify(struct ctl_table_poll *poll);
|
|
|
|
extern void setup_sysctl_set(struct ctl_table_set *p,
|
|
struct ctl_table_root *root,
|
|
int (*is_seen)(struct ctl_table_set *));
|
|
extern void retire_sysctl_set(struct ctl_table_set *set);
|
|
|
|
struct ctl_table_header *__register_sysctl_table(
|
|
struct ctl_table_set *set,
|
|
const char *path, struct ctl_table *table, size_t table_size);
|
|
struct ctl_table_header *register_sysctl_sz(const char *path, struct ctl_table *table,
|
|
size_t table_size);
|
|
void unregister_sysctl_table(struct ctl_table_header * table);
|
|
|
|
extern int sysctl_init_bases(void);
|
|
extern void __register_sysctl_init(const char *path, struct ctl_table *table,
|
|
const char *table_name, size_t table_size);
|
|
#define register_sysctl_init(path, table) \
|
|
__register_sysctl_init(path, table, #table, ARRAY_SIZE(table))
|
|
extern struct ctl_table_header *register_sysctl_mount_point(const char *path);
|
|
|
|
void do_sysctl_args(void);
|
|
bool sysctl_is_alias(char *param);
|
|
int do_proc_douintvec(struct ctl_table *table, int write,
|
|
void *buffer, size_t *lenp, loff_t *ppos,
|
|
int (*conv)(unsigned long *lvalp,
|
|
unsigned int *valp,
|
|
int write, void *data),
|
|
void *data);
|
|
|
|
extern int pwrsw_enabled;
|
|
extern int unaligned_enabled;
|
|
extern int unaligned_dump_stack;
|
|
extern int no_unaligned_warning;
|
|
|
|
#else /* CONFIG_SYSCTL */
|
|
|
|
static inline void register_sysctl_init(const char *path, struct ctl_table *table)
|
|
{
|
|
}
|
|
|
|
static inline struct ctl_table_header *register_sysctl_mount_point(const char *path)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
static inline struct ctl_table_header *register_sysctl_sz(const char *path,
|
|
struct ctl_table *table,
|
|
size_t table_size)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
static inline void unregister_sysctl_table(struct ctl_table_header * table)
|
|
{
|
|
}
|
|
|
|
static inline void setup_sysctl_set(struct ctl_table_set *p,
|
|
struct ctl_table_root *root,
|
|
int (*is_seen)(struct ctl_table_set *))
|
|
{
|
|
}
|
|
|
|
static inline void do_sysctl_args(void)
|
|
{
|
|
}
|
|
|
|
static inline bool sysctl_is_alias(char *param)
|
|
{
|
|
return false;
|
|
}
|
|
#endif /* CONFIG_SYSCTL */
|
|
|
|
int sysctl_max_threads(struct ctl_table *table, int write, void *buffer,
|
|
size_t *lenp, loff_t *ppos);
|
|
|
|
#endif /* _LINUX_SYSCTL_H */
|