Initial import

1 files changed, 712 insertions, 0 deletions

diff --git a/include/linux/tty.h b/include/linux/tty.h
new file mode 100644
index 000000000..d76631f61
--- /dev/null
+++ b/include/linux/tty.h
@@ -0,0 +1,712 @@
+#ifndef _LINUX_TTY_H
+#define _LINUX_TTY_H
+
+#include <linux/fs.h>
+#include <linux/major.h>
+#include <linux/termios.h>
+#include <linux/workqueue.h>
+#include <linux/tty_driver.h>
+#include <linux/tty_ldisc.h>
+#include <linux/mutex.h>
+#include <linux/tty_flags.h>
+#include <uapi/linux/tty.h>
+#include <linux/rwsem.h>
+#include <linux/llist.h>
+
+
+/*
+ * Lock subclasses for tty locks
+ *
+ * TTY_LOCK_NORMAL is for normal ttys and master ptys.
+ * TTY_LOCK_SLAVE is for slave ptys only.
+ *
+ * Lock subclasses are necessary for handling nested locking with pty pairs.
+ * tty locks which use nested locking:
+ *
+ * legacy_mutex - Nested tty locks are necessary for releasing pty pairs.
+ *		  The stable lock order is master pty first, then slave pty.
+ * termios_rwsem - The stable lock order is tty_buffer lock->termios_rwsem.
+ *		   Subclassing this lock enables the slave pty to hold its
+ *		   termios_rwsem when claiming the master tty_buffer lock.
+ * tty_buffer lock - slave ptys can claim nested buffer lock when handling
+ *		     signal chars. The stable lock order is slave pty, then
+ *		     master.
+ */
+
+enum {
+	TTY_LOCK_NORMAL = 0,
+	TTY_LOCK_SLAVE,
+};
+
+/*
+ * (Note: the *_driver.minor_start values 1, 64, 128, 192 are
+ * hardcoded at present.)
+ */
+#define NR_UNIX98_PTY_DEFAULT	4096      /* Default maximum for Unix98 ptys */
+#define NR_UNIX98_PTY_RESERVE	1024	  /* Default reserve for main devpts */
+#define NR_UNIX98_PTY_MAX	(1 << MINORBITS) /* Absolute limit */
+
+/*
+ * This character is the same as _POSIX_VDISABLE: it cannot be used as
+ * a c_cc[] character, but indicates that a particular special character
+ * isn't in use (eg VINTR has no character etc)
+ */
+#define __DISABLED_CHAR '\0'
+
+struct tty_buffer {
+	union {
+		struct tty_buffer *next;
+		struct llist_node free;
+	};
+	int used;
+	int size;
+	int commit;
+	int read;
+	int flags;
+	/* Data points here */
+	unsigned long data[0];
+};
+
+/* Values for .flags field of tty_buffer */
+#define TTYB_NORMAL	1	/* buffer has no flags buffer */
+
+static inline unsigned char *char_buf_ptr(struct tty_buffer *b, int ofs)
+{
+	return ((unsigned char *)b->data) + ofs;
+}
+
+static inline char *flag_buf_ptr(struct tty_buffer *b, int ofs)
+{
+	return (char *)char_buf_ptr(b, ofs) + b->size;
+}
+
+struct tty_bufhead {
+	struct tty_buffer *head;	/* Queue head */
+	struct work_struct work;
+	struct mutex	   lock;
+	atomic_t	   priority;
+	struct tty_buffer sentinel;
+	struct llist_head free;		/* Free queue head */
+	atomic_t	   mem_used;    /* In-use buffers excluding free list */
+	int		   mem_limit;
+	struct tty_buffer *tail;	/* Active buffer */
+};
+/*
+ * When a break, frame error, or parity error happens, these codes are
+ * stuffed into the flags buffer.
+ */
+#define TTY_NORMAL	0
+#define TTY_BREAK	1
+#define TTY_FRAME	2
+#define TTY_PARITY	3
+#define TTY_OVERRUN	4
+
+#define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR])
+#define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT])
+#define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE])
+#define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL])
+#define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF])
+#define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME])
+#define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN])
+#define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC])
+#define START_CHAR(tty) ((tty)->termios.c_cc[VSTART])
+#define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP])
+#define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP])
+#define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL])
+#define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT])
+#define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD])
+#define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE])
+#define LNEXT_CHAR(tty)	((tty)->termios.c_cc[VLNEXT])
+#define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2])
+
+#define _I_FLAG(tty, f)	((tty)->termios.c_iflag & (f))
+#define _O_FLAG(tty, f)	((tty)->termios.c_oflag & (f))
+#define _C_FLAG(tty, f)	((tty)->termios.c_cflag & (f))
+#define _L_FLAG(tty, f)	((tty)->termios.c_lflag & (f))
+
+#define I_IGNBRK(tty)	_I_FLAG((tty), IGNBRK)
+#define I_BRKINT(tty)	_I_FLAG((tty), BRKINT)
+#define I_IGNPAR(tty)	_I_FLAG((tty), IGNPAR)
+#define I_PARMRK(tty)	_I_FLAG((tty), PARMRK)
+#define I_INPCK(tty)	_I_FLAG((tty), INPCK)
+#define I_ISTRIP(tty)	_I_FLAG((tty), ISTRIP)
+#define I_INLCR(tty)	_I_FLAG((tty), INLCR)
+#define I_IGNCR(tty)	_I_FLAG((tty), IGNCR)
+#define I_ICRNL(tty)	_I_FLAG((tty), ICRNL)
+#define I_IUCLC(tty)	_I_FLAG((tty), IUCLC)
+#define I_IXON(tty)	_I_FLAG((tty), IXON)
+#define I_IXANY(tty)	_I_FLAG((tty), IXANY)
+#define I_IXOFF(tty)	_I_FLAG((tty), IXOFF)
+#define I_IMAXBEL(tty)	_I_FLAG((tty), IMAXBEL)
+#define I_IUTF8(tty)	_I_FLAG((tty), IUTF8)
+
+#define O_OPOST(tty)	_O_FLAG((tty), OPOST)
+#define O_OLCUC(tty)	_O_FLAG((tty), OLCUC)
+#define O_ONLCR(tty)	_O_FLAG((tty), ONLCR)
+#define O_OCRNL(tty)	_O_FLAG((tty), OCRNL)
+#define O_ONOCR(tty)	_O_FLAG((tty), ONOCR)
+#define O_ONLRET(tty)	_O_FLAG((tty), ONLRET)
+#define O_OFILL(tty)	_O_FLAG((tty), OFILL)
+#define O_OFDEL(tty)	_O_FLAG((tty), OFDEL)
+#define O_NLDLY(tty)	_O_FLAG((tty), NLDLY)
+#define O_CRDLY(tty)	_O_FLAG((tty), CRDLY)
+#define O_TABDLY(tty)	_O_FLAG((tty), TABDLY)
+#define O_BSDLY(tty)	_O_FLAG((tty), BSDLY)
+#define O_VTDLY(tty)	_O_FLAG((tty), VTDLY)
+#define O_FFDLY(tty)	_O_FLAG((tty), FFDLY)
+
+#define C_BAUD(tty)	_C_FLAG((tty), CBAUD)
+#define C_CSIZE(tty)	_C_FLAG((tty), CSIZE)
+#define C_CSTOPB(tty)	_C_FLAG((tty), CSTOPB)
+#define C_CREAD(tty)	_C_FLAG((tty), CREAD)
+#define C_PARENB(tty)	_C_FLAG((tty), PARENB)
+#define C_PARODD(tty)	_C_FLAG((tty), PARODD)
+#define C_HUPCL(tty)	_C_FLAG((tty), HUPCL)
+#define C_CLOCAL(tty)	_C_FLAG((tty), CLOCAL)
+#define C_CIBAUD(tty)	_C_FLAG((tty), CIBAUD)
+#define C_CRTSCTS(tty)	_C_FLAG((tty), CRTSCTS)
+#define C_CMSPAR(tty)	_C_FLAG((tty), CMSPAR)
+
+#define L_ISIG(tty)	_L_FLAG((tty), ISIG)
+#define L_ICANON(tty)	_L_FLAG((tty), ICANON)
+#define L_XCASE(tty)	_L_FLAG((tty), XCASE)
+#define L_ECHO(tty)	_L_FLAG((tty), ECHO)
+#define L_ECHOE(tty)	_L_FLAG((tty), ECHOE)
+#define L_ECHOK(tty)	_L_FLAG((tty), ECHOK)
+#define L_ECHONL(tty)	_L_FLAG((tty), ECHONL)
+#define L_NOFLSH(tty)	_L_FLAG((tty), NOFLSH)
+#define L_TOSTOP(tty)	_L_FLAG((tty), TOSTOP)
+#define L_ECHOCTL(tty)	_L_FLAG((tty), ECHOCTL)
+#define L_ECHOPRT(tty)	_L_FLAG((tty), ECHOPRT)
+#define L_ECHOKE(tty)	_L_FLAG((tty), ECHOKE)
+#define L_FLUSHO(tty)	_L_FLAG((tty), FLUSHO)
+#define L_PENDIN(tty)	_L_FLAG((tty), PENDIN)
+#define L_IEXTEN(tty)	_L_FLAG((tty), IEXTEN)
+#define L_EXTPROC(tty)	_L_FLAG((tty), EXTPROC)
+
+struct device;
+struct signal_struct;
+
+/*
+ * Port level information. Each device keeps its own port level information
+ * so provide a common structure for those ports wanting to use common support
+ * routines.
+ *
+ * The tty port has a different lifetime to the tty so must be kept apart.
+ * In addition be careful as tty -> port mappings are valid for the life
+ * of the tty object but in many cases port -> tty mappings are valid only
+ * until a hangup so don't use the wrong path.
+ */
+
+struct tty_port;
+
+struct tty_port_operations {
+	/* Return 1 if the carrier is raised */
+	int (*carrier_raised)(struct tty_port *port);
+	/* Control the DTR line */
+	void (*dtr_rts)(struct tty_port *port, int raise);
+	/* Called when the last close completes or a hangup finishes
+	   IFF the port was initialized. Do not use to free resources. Called
+	   under the port mutex to serialize against activate/shutdowns */
+	void (*shutdown)(struct tty_port *port);
+	/* Called under the port mutex from tty_port_open, serialized using
+	   the port mutex */
+        /* FIXME: long term getting the tty argument *out* of this would be
+           good for consoles */
+	int (*activate)(struct tty_port *port, struct tty_struct *tty);
+	/* Called on the final put of a port */
+	void (*destruct)(struct tty_port *port);
+};
+	
+struct tty_port {
+	struct tty_bufhead	buf;		/* Locked internally */
+	struct tty_struct	*tty;		/* Back pointer */
+	struct tty_struct	*itty;		/* internal back ptr */
+	const struct tty_port_operations *ops;	/* Port operations */
+	spinlock_t		lock;		/* Lock protecting tty field */
+	int			blocked_open;	/* Waiting to open */
+	int			count;		/* Usage count */
+	wait_queue_head_t	open_wait;	/* Open waiters */
+	wait_queue_head_t	close_wait;	/* Close waiters */
+	wait_queue_head_t	delta_msr_wait;	/* Modem status change */
+	unsigned long		flags;		/* TTY flags ASY_*/
+	unsigned char		console:1,	/* port is a console */
+				low_latency:1;	/* optional: tune for latency */
+	struct mutex		mutex;		/* Locking */
+	struct mutex		buf_mutex;	/* Buffer alloc lock */
+	unsigned char		*xmit_buf;	/* Optional buffer */
+	unsigned int		close_delay;	/* Close port delay */
+	unsigned int		closing_wait;	/* Delay for output */
+	int			drain_delay;	/* Set to zero if no pure time
+						   based drain is needed else
+						   set to size of fifo */
+	struct kref		kref;		/* Ref counter */
+};
+
+/*
+ * Where all of the state associated with a tty is kept while the tty
+ * is open.  Since the termios state should be kept even if the tty
+ * has been closed --- for things like the baud rate, etc --- it is
+ * not stored here, but rather a pointer to the real state is stored
+ * here.  Possible the winsize structure should have the same
+ * treatment, but (1) the default 80x24 is usually right and (2) it's
+ * most often used by a windowing system, which will set the correct
+ * size each time the window is created or resized anyway.
+ * 						- TYT, 9/14/92
+ */
+
+struct tty_operations;
+
+struct tty_struct {
+	int	magic;
+	struct kref kref;
+	struct device *dev;
+	struct tty_driver *driver;
+	const struct tty_operations *ops;
+	int index;
+
+	/* Protects ldisc changes: Lock tty not pty */
+	struct ld_semaphore ldisc_sem;
+	struct tty_ldisc *ldisc;
+
+	struct mutex atomic_write_lock;
+	struct mutex legacy_mutex;
+	struct mutex throttle_mutex;
+	struct rw_semaphore termios_rwsem;
+	struct mutex winsize_mutex;
+	spinlock_t ctrl_lock;
+	spinlock_t flow_lock;
+	/* Termios values are protected by the termios rwsem */
+	struct ktermios termios, termios_locked;
+	struct termiox *termiox;	/* May be NULL for unsupported */
+	char name[64];
+	struct pid *pgrp;		/* Protected by ctrl lock */
+	struct pid *session;
+	unsigned long flags;
+	int count;
+	struct winsize winsize;		/* winsize_mutex */
+	unsigned long stopped:1,	/* flow_lock */
+		      flow_stopped:1,
+		      unused:BITS_PER_LONG - 2;
+	int hw_stopped;
+	unsigned long ctrl_status:8,	/* ctrl_lock */
+		      packet:1,
+		      unused_ctrl:BITS_PER_LONG - 9;
+	unsigned int receive_room;	/* Bytes free for queue */
+	int flow_change;
+
+	struct tty_struct *link;
+	struct fasync_struct *fasync;
+	int alt_speed;		/* For magic substitution of 38400 bps */
+	wait_queue_head_t write_wait;
+	wait_queue_head_t read_wait;
+	struct work_struct hangup_work;
+	void *disc_data;
+	void *driver_data;
+	struct list_head tty_files;
+
+#define N_TTY_BUF_SIZE 4096
+
+	int closing;
+	unsigned char *write_buf;
+	int write_cnt;
+	/* If the tty has a pending do_SAK, queue it here - akpm */
+	struct work_struct SAK_work;
+	struct tty_port *port;
+};
+
+/* Each of a tty's open files has private_data pointing to tty_file_private */
+struct tty_file_private {
+	struct tty_struct *tty;
+	struct file *file;
+	struct list_head list;
+};
+
+/* tty magic number */
+#define TTY_MAGIC		0x5401
+
+/*
+ * These bits are used in the flags field of the tty structure.
+ *
+ * So that interrupts won't be able to mess up the queues,
+ * copy_to_cooked must be atomic with respect to itself, as must
+ * tty->write.  Thus, you must use the inline functions set_bit() and
+ * clear_bit() to make things atomic.
+ */
+#define TTY_THROTTLED 		0	/* Call unthrottle() at threshold min */
+#define TTY_IO_ERROR 		1	/* Cause an I/O error (may be no ldisc too) */
+#define TTY_OTHER_CLOSED 	2	/* Other side (if any) has closed */
+#define TTY_EXCLUSIVE 		3	/* Exclusive open mode */
+#define TTY_DEBUG 		4	/* Debugging */
+#define TTY_DO_WRITE_WAKEUP 	5	/* Call write_wakeup after queuing new */
+#define TTY_OTHER_DONE		6	/* Closed pty has completed input processing */
+#define TTY_LDISC_OPEN	 	11	/* Line discipline is open */
+#define TTY_PTY_LOCK 		16	/* pty private */
+#define TTY_NO_WRITE_SPLIT 	17	/* Preserve write boundaries to driver */
+#define TTY_HUPPED 		18	/* Post driver->hangup() */
+#define TTY_LDISC_HALTED	22	/* Line discipline is halted */
+
+#define TTY_WRITE_FLUSH(tty) tty_write_flush((tty))
+
+/* Values for tty->flow_change */
+#define TTY_THROTTLE_SAFE 1
+#define TTY_UNTHROTTLE_SAFE 2
+
+static inline void __tty_set_flow_change(struct tty_struct *tty, int val)
+{
+	tty->flow_change = val;
+}
+
+static inline void tty_set_flow_change(struct tty_struct *tty, int val)
+{
+	tty->flow_change = val;
+	smp_mb();
+}
+
+#ifdef CONFIG_TTY
+extern void console_init(void);
+extern void tty_kref_put(struct tty_struct *tty);
+extern struct pid *tty_get_pgrp(struct tty_struct *tty);
+extern void tty_vhangup_self(void);
+extern void disassociate_ctty(int priv);
+extern dev_t tty_devnum(struct tty_struct *tty);
+extern void proc_clear_tty(struct task_struct *p);
+extern struct tty_struct *get_current_tty(void);
+/* tty_io.c */
+extern int __init tty_init(void);
+#else
+static inline void console_init(void)
+{ }
+static inline void tty_kref_put(struct tty_struct *tty)
+{ }
+static inline struct pid *tty_get_pgrp(struct tty_struct *tty)
+{ return NULL; }
+static inline void tty_vhangup_self(void)
+{ }
+static inline void disassociate_ctty(int priv)
+{ }
+static inline dev_t tty_devnum(struct tty_struct *tty)
+{ return 0; }
+static inline void proc_clear_tty(struct task_struct *p)
+{ }
+static inline struct tty_struct *get_current_tty(void)
+{ return NULL; }
+/* tty_io.c */
+static inline int __init tty_init(void)
+{ return 0; }
+#endif
+
+extern void tty_write_flush(struct tty_struct *);
+
+extern struct ktermios tty_std_termios;
+
+extern int vcs_init(void);
+
+extern struct class *tty_class;
+
+/**
+ *	tty_kref_get		-	get a tty reference
+ *	@tty: tty device
+ *
+ *	Return a new reference to a tty object. The caller must hold
+ *	sufficient locks/counts to ensure that their existing reference cannot
+ *	go away
+ */
+
+static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
+{
+	if (tty)
+		kref_get(&tty->kref);
+	return tty;
+}
+
+extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode,
+			      const char *routine);
+extern char *tty_name(struct tty_struct *tty, char *buf);
+extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
+extern int tty_check_change(struct tty_struct *tty);
+extern void __stop_tty(struct tty_struct *tty);
+extern void stop_tty(struct tty_struct *tty);
+extern void __start_tty(struct tty_struct *tty);
+extern void start_tty(struct tty_struct *tty);
+extern int tty_register_driver(struct tty_driver *driver);
+extern int tty_unregister_driver(struct tty_driver *driver);
+extern struct device *tty_register_device(struct tty_driver *driver,
+					  unsigned index, struct device *dev);
+extern struct device *tty_register_device_attr(struct tty_driver *driver,
+				unsigned index, struct device *device,
+				void *drvdata,
+				const struct attribute_group **attr_grp);
+extern void tty_unregister_device(struct tty_driver *driver, unsigned index);
+extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp,
+			     int buflen);
+extern void tty_write_message(struct tty_struct *tty, char *msg);
+extern int tty_send_xchar(struct tty_struct *tty, char ch);
+extern int tty_put_char(struct tty_struct *tty, unsigned char c);
+extern int tty_chars_in_buffer(struct tty_struct *tty);
+extern int tty_write_room(struct tty_struct *tty);
+extern void tty_driver_flush_buffer(struct tty_struct *tty);
+extern void tty_throttle(struct tty_struct *tty);
+extern void tty_unthrottle(struct tty_struct *tty);
+extern int tty_throttle_safe(struct tty_struct *tty);
+extern int tty_unthrottle_safe(struct tty_struct *tty);
+extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
+extern void tty_driver_remove_tty(struct tty_driver *driver,
+				  struct tty_struct *tty);
+extern void tty_free_termios(struct tty_struct *tty);
+extern int is_current_pgrp_orphaned(void);
+extern int is_ignored(int sig);
+extern int tty_signal(int sig, struct tty_struct *tty);
+extern void tty_hangup(struct tty_struct *tty);
+extern void tty_vhangup(struct tty_struct *tty);
+extern int tty_hung_up_p(struct file *filp);
+extern void do_SAK(struct tty_struct *tty);
+extern void __do_SAK(struct tty_struct *tty);
+extern void no_tty(void);
+extern void tty_buffer_free_all(struct tty_port *port);
+extern void tty_buffer_flush(struct tty_struct *tty, struct tty_ldisc *ld);
+extern void tty_buffer_init(struct tty_port *port);
+extern void tty_buffer_set_lock_subclass(struct tty_port *port);
+extern speed_t tty_termios_baud_rate(struct ktermios *termios);
+extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
+extern void tty_termios_encode_baud_rate(struct ktermios *termios,
+						speed_t ibaud, speed_t obaud);
+extern void tty_encode_baud_rate(struct tty_struct *tty,
+						speed_t ibaud, speed_t obaud);
+
+/**
+ *	tty_get_baud_rate	-	get tty bit rates
+ *	@tty: tty to query
+ *
+ *	Returns the baud rate as an integer for this terminal. The
+ *	termios lock must be held by the caller and the terminal bit
+ *	flags may be updated.
+ *
+ *	Locking: none
+ */
+static inline speed_t tty_get_baud_rate(struct tty_struct *tty)
+{
+	return tty_termios_baud_rate(&tty->termios);
+}
+
+extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
+extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b);
+extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
+
+extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *);
+extern void tty_ldisc_deref(struct tty_ldisc *);
+extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *);
+extern void tty_ldisc_hangup(struct tty_struct *tty);
+extern const struct file_operations tty_ldiscs_proc_fops;
+
+extern void tty_wakeup(struct tty_struct *tty);
+extern void tty_ldisc_flush(struct tty_struct *tty);
+
+extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
+			unsigned int cmd, unsigned long arg);
+extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
+extern void tty_default_fops(struct file_operations *fops);
+extern struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx);
+extern int tty_alloc_file(struct file *file);
+extern void tty_add_file(struct tty_struct *tty, struct file *file);
+extern void tty_free_file(struct file *file);
+extern void free_tty_struct(struct tty_struct *tty);
+extern void deinitialize_tty_struct(struct tty_struct *tty);
+extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx);
+extern int tty_release(struct inode *inode, struct file *filp);
+extern int tty_init_termios(struct tty_struct *tty);
+extern int tty_standard_install(struct tty_driver *driver,
+		struct tty_struct *tty);
+
+extern struct mutex tty_mutex;
+extern spinlock_t tty_files_lock;
+
+#define tty_is_writelocked(tty)  (mutex_is_locked(&tty->atomic_write_lock))
+
+extern void tty_port_init(struct tty_port *port);
+extern void tty_port_link_device(struct tty_port *port,
+		struct tty_driver *driver, unsigned index);
+extern struct device *tty_port_register_device(struct tty_port *port,
+		struct tty_driver *driver, unsigned index,
+		struct device *device);
+extern struct device *tty_port_register_device_attr(struct tty_port *port,
+		struct tty_driver *driver, unsigned index,
+		struct device *device, void *drvdata,
+		const struct attribute_group **attr_grp);
+extern int tty_port_alloc_xmit_buf(struct tty_port *port);
+extern void tty_port_free_xmit_buf(struct tty_port *port);
+extern void tty_port_destroy(struct tty_port *port);
+extern void tty_port_put(struct tty_port *port);
+
+static inline struct tty_port *tty_port_get(struct tty_port *port)
+{
+	if (port && kref_get_unless_zero(&port->kref))
+		return port;
+	return NULL;
+}
+
+/* If the cts flow control is enabled, return true. */
+static inline bool tty_port_cts_enabled(struct tty_port *port)
+{
+	return port->flags & ASYNC_CTS_FLOW;
+}
+
+extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
+extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
+extern int tty_port_carrier_raised(struct tty_port *port);
+extern void tty_port_raise_dtr_rts(struct tty_port *port);
+extern void tty_port_lower_dtr_rts(struct tty_port *port);
+extern void tty_port_hangup(struct tty_port *port);
+extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal);
+extern void tty_port_tty_wakeup(struct tty_port *port);
+extern int tty_port_block_til_ready(struct tty_port *port,
+				struct tty_struct *tty, struct file *filp);
+extern int tty_port_close_start(struct tty_port *port,
+				struct tty_struct *tty, struct file *filp);
+extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
+extern void tty_port_close(struct tty_port *port,
+				struct tty_struct *tty, struct file *filp);
+extern int tty_port_install(struct tty_port *port, struct tty_driver *driver,
+				struct tty_struct *tty);
+extern int tty_port_open(struct tty_port *port,
+				struct tty_struct *tty, struct file *filp);
+static inline int tty_port_users(struct tty_port *port)
+{
+	return port->count + port->blocked_open;
+}
+
+extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc);
+extern int tty_unregister_ldisc(int disc);
+extern int tty_set_ldisc(struct tty_struct *tty, int ldisc);
+extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty);
+extern void tty_ldisc_release(struct tty_struct *tty);
+extern void tty_ldisc_init(struct tty_struct *tty);
+extern void tty_ldisc_deinit(struct tty_struct *tty);
+extern void tty_ldisc_begin(void);
+
+static inline int tty_ldisc_receive_buf(struct tty_ldisc *ld, unsigned char *p,
+					char *f, int count)
+{
+	if (ld->ops->receive_buf2)
+		count = ld->ops->receive_buf2(ld->tty, p, f, count);
+	else {
+		count = min_t(int, count, ld->tty->receive_room);
+		if (count)
+			ld->ops->receive_buf(ld->tty, p, f, count);
+	}
+	return count;
+}
+
+
+/* n_tty.c */
+extern struct tty_ldisc_ops tty_ldisc_N_TTY;
+extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
+
+/* tty_audit.c */
+#ifdef CONFIG_AUDIT
+extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data,
+			       size_t size, unsigned icanon);
+extern void tty_audit_exit(void);
+extern void tty_audit_fork(struct signal_struct *sig);
+extern void tty_audit_tiocsti(struct tty_struct *tty, char ch);
+extern void tty_audit_push(struct tty_struct *tty);
+extern int tty_audit_push_current(void);
+#else
+static inline void tty_audit_add_data(struct tty_struct *tty,
+		unsigned char *data, size_t size, unsigned icanon)
+{
+}
+static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch)
+{
+}
+static inline void tty_audit_exit(void)
+{
+}
+static inline void tty_audit_fork(struct signal_struct *sig)
+{
+}
+static inline void tty_audit_push(struct tty_struct *tty)
+{
+}
+static inline int tty_audit_push_current(void)
+{
+	return 0;
+}
+#endif
+
+/* tty_ioctl.c */
+extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
+		       unsigned int cmd, unsigned long arg);
+extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file,
+		       unsigned int cmd, unsigned long arg);
+
+/* vt.c */
+
+extern int vt_ioctl(struct tty_struct *tty,
+		    unsigned int cmd, unsigned long arg);
+
+extern long vt_compat_ioctl(struct tty_struct *tty,
+		     unsigned int cmd, unsigned long arg);
+
+/* tty_mutex.c */
+/* functions for preparation of BKL removal */
+extern void __lockfunc tty_lock(struct tty_struct *tty);
+extern void __lockfunc tty_unlock(struct tty_struct *tty);
+extern void __lockfunc tty_lock_slave(struct tty_struct *tty);
+extern void __lockfunc tty_unlock_slave(struct tty_struct *tty);
+extern void tty_set_lock_subclass(struct tty_struct *tty);
+/*
+ * this shall be called only from where BTM is held (like close)
+ *
+ * We need this to ensure nobody waits for us to finish while we are waiting.
+ * Without this we were encountering system stalls.
+ *
+ * This should be indeed removed with BTM removal later.
+ *
+ * Locking: BTM required. Nobody is allowed to hold port->mutex.
+ */
+static inline void tty_wait_until_sent_from_close(struct tty_struct *tty,
+		long timeout)
+{
+	tty_unlock(tty); /* tty->ops->close holds the BTM, drop it while waiting */
+	tty_wait_until_sent(tty, timeout);
+	tty_lock(tty);
+}
+
+/*
+ * wait_event_interruptible_tty -- wait for a condition with the tty lock held
+ *
+ * The condition we are waiting for might take a long time to
+ * become true, or might depend on another thread taking the
+ * BTM. In either case, we need to drop the BTM to guarantee
+ * forward progress. This is a leftover from the conversion
+ * from the BKL and should eventually get removed as the BTM
+ * falls out of use.
+ *
+ * Do not use in new code.
+ */
+#define wait_event_interruptible_tty(tty, wq, condition)		\
+({									\
+	int __ret = 0;							\
+	if (!(condition))						\
+		__ret = __wait_event_interruptible_tty(tty, wq,		\
+						       condition);	\
+	__ret;								\
+})
+
+#define __wait_event_interruptible_tty(tty, wq, condition)		\
+	___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0,		\
+			tty_unlock(tty);				\
+			schedule();					\
+			tty_lock(tty))
+
+#ifdef CONFIG_PROC_FS
+extern void proc_tty_register_driver(struct tty_driver *);
+extern void proc_tty_unregister_driver(struct tty_driver *);
+#else
+static inline void proc_tty_register_driver(struct tty_driver *d) {}
+static inline void proc_tty_unregister_driver(struct tty_driver *d) {}
+#endif
+
+#endif