include/linux/tty.h - third_party/kernel - Git at Google

 /* SPDX-License-Identifier: GPL-2.0 */
 #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_buffer.h>
 #include <linux/tty_driver.h>
 #include <linux/tty_ldisc.h>
 #include <linux/tty_port.h>
 #include <linux/mutex.h>
 #include <linux/tty_flags.h>
 #include <uapi/linux/tty.h>
 #include <linux/rwsem.h>
 #include <linux/llist.h>


 /*
  * (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'

 #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;
 struct tty_operations;

 /**
  * struct tty_struct - state associated with a tty while open
  *
  * @flow.lock: lock for flow members
  * @flow.stopped: tty stopped/started by tty_stop/tty_start
  * @flow.tco_stopped: tty stopped/started by TCOOFF/TCOON ioctls (it has
  *		      precedense over @flow.stopped)
  * @flow.unused: alignment for Alpha, so that no members other than @flow.* are
  *		 modified by the same 64b word store. The @flow's __aligned is
  *		 there for the very same reason.
  * @ctrl.lock: lock for ctrl members
  * @ctrl.pgrp: process group of this tty (setpgrp(2))
  * @ctrl.session: session of this tty (setsid(2)). Writes are protected by both
  *		  @ctrl.lock and legacy mutex, readers must use at least one of
  *		  them.
  * @ctrl.pktstatus: packet mode status (bitwise OR of TIOCPKT_* constants)
  * @ctrl.packet: packet mode enabled
  *
  * All of the state associated with a tty while the tty is open. Persistent
  * storage for tty devices is referenced here as @port in struct tty_port.
  */
 struct tty_struct {
 	int	magic;
 	struct kref kref;
 	struct device *dev;	/* class device or NULL (e.g. ptys, serdev) */
 	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;
 	/* Termios values are protected by the termios rwsem */
 	struct ktermios termios, termios_locked;
 	char name[64];
 	unsigned long flags;
 	int count;
 	struct winsize winsize;		/* winsize_mutex */

 	struct {
 		spinlock_t lock;
 		bool stopped;
 		bool tco_stopped;
 		unsigned long unused[0];
 	} __aligned(sizeof(unsigned long)) flow;

 	struct {
 		spinlock_t lock;
 		struct pid *pgrp;
 		struct pid *session;
 		unsigned char pktstatus;
 		bool packet;
 		unsigned long unused[0];
 	} __aligned(sizeof(unsigned long)) ctrl;

 	int hw_stopped;
 	unsigned int receive_room;	/* Bytes free for queue */
 	int flow_change;

 	struct tty_struct *link;
 	struct fasync_struct *fasync;
 	wait_queue_head_t write_wait;
 	wait_queue_head_t read_wait;
 	struct work_struct hangup_work;
 	void *disc_data;
 	void *driver_data;
 	spinlock_t files_lock;		/* protects tty_files list */
 	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;
 } __randomize_layout;

 /* 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_DO_WRITE_WAKEUP 	5	/* Call write_wakeup after queuing new */
 #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_HUPPING		19	/* Hangup in progress */
 #define TTY_LDISC_CHANGING	20	/* Change pending - non-block IO */
 #define TTY_LDISC_HALTED	22	/* Line discipline is halted */

 static inline bool tty_io_nonblock(struct tty_struct *tty, struct file *file)
 {
 	return file->f_flags & O_NONBLOCK ||
 		test_bit(TTY_LDISC_CHANGING, &tty->flags);
 }

 static inline bool tty_io_error(struct tty_struct *tty)
 {
 	return test_bit(TTY_IO_ERROR, &tty->flags);
 }

 static inline bool tty_throttled(struct tty_struct *tty)
 {
 	return test_bit(TTY_THROTTLED, &tty->flags);
 }

 #ifdef CONFIG_TTY
 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);
 extern const char *tty_name(const struct tty_struct *tty);
 extern struct tty_struct *tty_kopen_exclusive(dev_t device);
 extern struct tty_struct *tty_kopen_shared(dev_t device);
 extern void tty_kclose(struct tty_struct *tty);
 extern int tty_dev_name_to_number(const char *name, dev_t *number);
 #else
 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; }
 static inline const char *tty_name(const struct tty_struct *tty)
 { return "(none)"; }
 static inline struct tty_struct *tty_kopen_exclusive(dev_t device)
 { return ERR_PTR(-ENODEV); }
 static inline void tty_kclose(struct tty_struct *tty)
 { }
 static inline int tty_dev_name_to_number(const char *name, dev_t *number)
 { return -ENOTSUPP; }
 #endif

 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 const char *tty_driver_name(const struct tty_struct *tty);
 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
 extern void stop_tty(struct tty_struct *tty);
 extern void start_tty(struct tty_struct *tty);
 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 unsigned int tty_chars_in_buffer(struct tty_struct *tty);
 extern unsigned int tty_write_room(struct tty_struct *tty);
 extern void tty_driver_flush_buffer(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 int tty_get_icount(struct tty_struct *tty,
 			  struct serial_icounter_struct *icount);
 extern int is_current_pgrp_orphaned(void);
 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 speed_t tty_termios_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);
 }

 unsigned char tty_get_char_size(unsigned int cflag);
 unsigned char tty_get_frame_size(unsigned int cflag);

 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
 extern int tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b);
 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);

 extern void tty_wakeup(struct tty_struct *tty);

 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 struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx);
 extern void tty_release_struct(struct tty_struct *tty, int idx);
 extern void tty_init_termios(struct tty_struct *tty);
 extern void tty_save_termios(struct tty_struct *tty);
 extern int tty_standard_install(struct tty_driver *driver,
 		struct tty_struct *tty);

 extern struct mutex tty_mutex;

 /* n_tty.c */
 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
 #ifdef CONFIG_TTY
 extern void __init n_tty_init(void);
 #else
 static inline void n_tty_init(void) { }
 #endif

 /* tty_audit.c */
 #ifdef CONFIG_AUDIT
 extern void tty_audit_exit(void);
 extern void tty_audit_fork(struct signal_struct *sig);
 extern int tty_audit_push(void);
 #else
 static inline void tty_audit_exit(void)
 {
 }
 static inline void tty_audit_fork(struct signal_struct *sig)
 {
 }
 static inline int tty_audit_push(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);

 /* 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 tty_lock(struct tty_struct *tty);
 extern int  tty_lock_interruptible(struct tty_struct *tty);
 extern void tty_unlock(struct tty_struct *tty);
 extern void tty_lock_slave(struct tty_struct *tty);
 extern void tty_unlock_slave(struct tty_struct *tty);
 extern void tty_set_lock_subclass(struct tty_struct *tty);

 #endif
	/* SPDX-License-Identifier: GPL-2.0 */
	#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_buffer.h>
	#include <linux/tty_driver.h>
	#include <linux/tty_ldisc.h>
	#include <linux/tty_port.h>
	#include <linux/mutex.h>
	#include <linux/tty_flags.h>
	#include <uapi/linux/tty.h>
	#include <linux/rwsem.h>
	#include <linux/llist.h>


	/*
	* (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'

	#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;
	struct tty_operations;

	/**
	* struct tty_struct - state associated with a tty while open
	*
	* @flow.lock: lock for flow members
	* @flow.stopped: tty stopped/started by tty_stop/tty_start
	* @flow.tco_stopped: tty stopped/started by TCOOFF/TCOON ioctls (it has
	* precedense over @flow.stopped)
	* @flow.unused: alignment for Alpha, so that no members other than @flow.* are
	* modified by the same 64b word store. The @flow's __aligned is
	* there for the very same reason.
	* @ctrl.lock: lock for ctrl members
	* @ctrl.pgrp: process group of this tty (setpgrp(2))
	* @ctrl.session: session of this tty (setsid(2)). Writes are protected by both
	* @ctrl.lock and legacy mutex, readers must use at least one of
	* them.
	* @ctrl.pktstatus: packet mode status (bitwise OR of TIOCPKT_* constants)
	* @ctrl.packet: packet mode enabled
	*
	* All of the state associated with a tty while the tty is open. Persistent
	* storage for tty devices is referenced here as @port in struct tty_port.
	*/
	struct tty_struct {
	int magic;
	struct kref kref;
	struct device dev; / class device or NULL (e.g. ptys, serdev) */
	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;
	/* Termios values are protected by the termios rwsem */
	struct ktermios termios, termios_locked;
	char name[64];
	unsigned long flags;
	int count;
	struct winsize winsize; /* winsize_mutex */

	struct {
	spinlock_t lock;
	bool stopped;
	bool tco_stopped;
	unsigned long unused[0];
	} __aligned(sizeof(unsigned long)) flow;

	struct {
	spinlock_t lock;
	struct pid *pgrp;
	struct pid *session;
	unsigned char pktstatus;
	bool packet;
	unsigned long unused[0];
	} __aligned(sizeof(unsigned long)) ctrl;

	int hw_stopped;
	unsigned int receive_room; /* Bytes free for queue */
	int flow_change;

	struct tty_struct *link;
	struct fasync_struct *fasync;
	wait_queue_head_t write_wait;
	wait_queue_head_t read_wait;
	struct work_struct hangup_work;
	void *disc_data;
	void *driver_data;
	spinlock_t files_lock; /* protects tty_files list */
	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;
	} __randomize_layout;

	/* 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_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */
	#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_HUPPING 19 /* Hangup in progress */
	#define TTY_LDISC_CHANGING 20 /* Change pending - non-block IO */
	#define TTY_LDISC_HALTED 22 /* Line discipline is halted */

	static inline bool tty_io_nonblock(struct tty_struct tty, struct file file)
	{
	return file->f_flags & O_NONBLOCK \|\|
	test_bit(TTY_LDISC_CHANGING, &tty->flags);
	}

	static inline bool tty_io_error(struct tty_struct *tty)
	{
	return test_bit(TTY_IO_ERROR, &tty->flags);
	}

	static inline bool tty_throttled(struct tty_struct *tty)
	{
	return test_bit(TTY_THROTTLED, &tty->flags);
	}

	#ifdef CONFIG_TTY
	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);
	extern const char tty_name(const struct tty_struct tty);
	extern struct tty_struct *tty_kopen_exclusive(dev_t device);
	extern struct tty_struct *tty_kopen_shared(dev_t device);
	extern void tty_kclose(struct tty_struct *tty);
	extern int tty_dev_name_to_number(const char name, dev_t number);
	#else
	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; }
	static inline const char tty_name(const struct tty_struct tty)
	{ return "(none)"; }
	static inline struct tty_struct *tty_kopen_exclusive(dev_t device)
	{ return ERR_PTR(-ENODEV); }
	static inline void tty_kclose(struct tty_struct *tty)
	{ }
	static inline int tty_dev_name_to_number(const char name, dev_t number)
	{ return -ENOTSUPP; }
	#endif

	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 const char tty_driver_name(const struct tty_struct tty);
	extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
	extern void stop_tty(struct tty_struct *tty);
	extern void start_tty(struct tty_struct *tty);
	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 unsigned int tty_chars_in_buffer(struct tty_struct *tty);
	extern unsigned int tty_write_room(struct tty_struct *tty);
	extern void tty_driver_flush_buffer(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 int tty_get_icount(struct tty_struct *tty,
	struct serial_icounter_struct *icount);
	extern int is_current_pgrp_orphaned(void);
	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 speed_t tty_termios_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);
	}

	unsigned char tty_get_char_size(unsigned int cflag);
	unsigned char tty_get_frame_size(unsigned int cflag);

	extern void tty_termios_copy_hw(struct ktermios new, struct ktermios old);
	extern int tty_termios_hw_change(const struct ktermios a, const struct ktermios b);
	extern int tty_set_termios(struct tty_struct tty, struct ktermios kt);

	extern void tty_wakeup(struct tty_struct *tty);

	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 struct tty_struct tty_init_dev(struct tty_driver driver, int idx);
	extern void tty_release_struct(struct tty_struct *tty, int idx);
	extern void tty_init_termios(struct tty_struct *tty);
	extern void tty_save_termios(struct tty_struct *tty);
	extern int tty_standard_install(struct tty_driver *driver,
	struct tty_struct *tty);

	extern struct mutex tty_mutex;

	/* n_tty.c */
	extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
	#ifdef CONFIG_TTY
	extern void __init n_tty_init(void);
	#else
	static inline void n_tty_init(void) { }
	#endif

	/* tty_audit.c */
	#ifdef CONFIG_AUDIT
	extern void tty_audit_exit(void);
	extern void tty_audit_fork(struct signal_struct *sig);
	extern int tty_audit_push(void);
	#else
	static inline void tty_audit_exit(void)
	{
	}
	static inline void tty_audit_fork(struct signal_struct *sig)
	{
	}
	static inline int tty_audit_push(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);

	/* 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 tty_lock(struct tty_struct *tty);
	extern int tty_lock_interruptible(struct tty_struct *tty);
	extern void tty_unlock(struct tty_struct *tty);
	extern void tty_lock_slave(struct tty_struct *tty);
	extern void tty_unlock_slave(struct tty_struct *tty);
	extern void tty_set_lock_subclass(struct tty_struct *tty);

	#endif