original, as distributed

1 files changed, 217 insertions, 0 deletions

diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
new file mode 100644
index 0000000..14a8ff2
--- /dev/null
+++ b/include/linux/sysctl.h
@@ -0,0 +1,217 @@
+/*
+ * 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 struct ctl_table ctl_table;
+
+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);
+#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 */
+
+#endif /* _LINUX_SYSCTL_H */