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-rw-r--r--kernel/include/linux/sysctl.h221
1 files changed, 221 insertions, 0 deletions
diff --git a/kernel/include/linux/sysctl.h b/kernel/include/linux/sysctl.h
new file mode 100644
index 000000000..fa7bc2992
--- /dev/null
+++ b/kernel/include/linux/sysctl.h
@@ -0,0 +1,221 @@
+/*
+ * 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 <uapi/linux/sysctl.h>
+
+/* For the /proc/sys support */
+struct ctl_table;
+struct nsproxy;
+struct ctl_table_root;
+struct ctl_table_header;
+struct ctl_dir;
+
+typedef int proc_handler (struct ctl_table *ctl, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos);
+
+extern int proc_dostring(struct ctl_table *, int,
+ void __user *, size_t *, loff_t *);
+extern int proc_dointvec(struct ctl_table *, int,
+ void __user *, size_t *, loff_t *);
+extern int proc_dointvec_minmax(struct ctl_table *, int,
+ void __user *, size_t *, loff_t *);
+extern int proc_dointvec_jiffies(struct ctl_table *, int,
+ void __user *, size_t *, loff_t *);
+extern int proc_dointvec_userhz_jiffies(struct ctl_table *, int,
+ void __user *, size_t *, loff_t *);
+extern int proc_dointvec_ms_jiffies(struct ctl_table *, int,
+ void __user *, size_t *, loff_t *);
+extern int proc_doulongvec_minmax(struct ctl_table *, int,
+ void __user *, size_t *, loff_t *);
+extern int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int,
+ void __user *, size_t *, loff_t *);
+extern int proc_do_large_bitmap(struct ctl_table *, int,
+ void __user *, size_t *, loff_t *);
+
+/*
+ * Register a set of sysctl names by calling register_sysctl_table
+ * 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 both for sys_sysctl(2) and
+ * 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.
+ *
+ * sysctl(2) can automatically manage read and write requests through
+ * the sysctl table. 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;
+ struct ctl_table *child; /* Deprecated */
+ proc_handler *proc_handler; /* Callback for text formatting */
+ struct ctl_table_poll *poll;
+ void *extra1;
+ void *extra2;
+};
+
+struct ctl_node {
+ struct rb_node node;
+ struct ctl_table_header *header;
+};
+
+/* struct ctl_table_header is used to maintain dynamic lists of
+ struct ctl_table trees. */
+struct ctl_table_header
+{
+ union {
+ struct {
+ struct ctl_table *ctl_table;
+ 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 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,
+ struct nsproxy *namespaces);
+ int (*permissions)(struct ctl_table_header *head, struct ctl_table *table);
+};
+
+/* struct ctl_path describes where in the hierarchy a table is added */
+struct ctl_path {
+ const char *procname;
+};
+
+#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);
+
+void register_sysctl_root(struct ctl_table_root *root);
+struct ctl_table_header *__register_sysctl_table(
+ struct ctl_table_set *set,
+ const char *path, struct ctl_table *table);
+struct ctl_table_header *__register_sysctl_paths(
+ struct ctl_table_set *set,
+ const struct ctl_path *path, struct ctl_table *table);
+struct ctl_table_header *register_sysctl(const char *path, struct ctl_table *table);
+struct ctl_table_header *register_sysctl_table(struct ctl_table * table);
+struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
+ struct ctl_table *table);
+
+void unregister_sysctl_table(struct ctl_table_header * table);
+
+extern int sysctl_init(void);
+
+extern struct ctl_table sysctl_mount_point[];
+
+#else /* CONFIG_SYSCTL */
+static inline struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
+{
+ return NULL;
+}
+
+static inline struct ctl_table_header *register_sysctl_paths(
+ const struct ctl_path *path, struct ctl_table *table)
+{
+ 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 *))
+{
+}
+
+#endif /* CONFIG_SYSCTL */
+
+int sysctl_max_threads(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos);
+
+#endif /* _LINUX_SYSCTL_H */