1 files changed, 301 insertions, 0 deletions
diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
new file mode 100644
index 000000000..61b40ea81
--- /dev/null
+++ b/include/linux/sysctl.h
@@ -0,0 +1,301 @@
+/* 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);
+};
+
+/* struct ctl_path describes where in the hierarchy a table is added */
+struct ctl_path {
+	const char *procname;
+};
+
+#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;
+
+#define SYSCTL_PERM_EMPTY_DIR	(1 << 0)
+
+#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 */