#define TTY_PORT_KOPENED 5 /* device exclusively opened by
kernel */
-/*
- * 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 - 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 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;
char name[64];
- struct pid *pgrp; /* Protected by ctrl lock */
- /*
- * Writes protected by both ctrl lock and legacy mutex, readers must use
- * at least one of them.
- */
- 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;
+
+ 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 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;
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 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_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);
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);
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_register_ldisc(struct tty_ldisc_ops *new_ldisc);
+extern void tty_unregister_ldisc(struct tty_ldisc_ops *ldisc);
extern int tty_set_ldisc(struct tty_struct *tty, int disc);
extern int tty_ldisc_receive_buf(struct tty_ldisc *ld, const unsigned char *p,
- char *f, int count);
+ const char *f, int count);
/* n_tty.c */
extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);