d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
be48ab92ac
freebsd-skq/sys/sys/tty.h
Gleb Smirnoff e1e585a87c - Rename tty_makedev() into tty_makedevf() and make it capable 
to fail and return error.
- Use make_dev_p() in tty_makedevf() instead of make_dev_cred().
- Always pass MAKEDEV_CHECKNAME flag.
- Optionally pass MAKEDEV_REF flag.
- Provide macro for compatibility with old API.

This fixes races with simultaneous creation and desctruction of
ttys, and makes it possible to call tty_makedevf() from device
cloners.

A race in tty_watermarks() still exist, since the latter drops
lock for M_WAITOK allocation. This will be addressed in separate
commit.

Reviewed by:	kib
Sponsored by:	Nginx, Inc.
2013-12-18 12:50:43 +00:00

228 lines
8.6 KiB
C
Raw Blame History

/*-
* Copyright (c) 2008 Ed Schouten <ed@FreeBSD.org>
* All rights reserved.
*
* Portions of this software were developed under sponsorship from Snow
* B.V., the Netherlands.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _SYS_TTY_H_
#define _SYS_TTY_H_
#include <sys/param.h>
#include <sys/queue.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/condvar.h>
#include <sys/selinfo.h>
#include <sys/_termios.h>
#include <sys/ttycom.h>
#include <sys/ttyqueue.h>
struct cdev;
struct file;
struct pgrp;
struct session;
struct ucred;
struct ttydevsw;
/*
* Per-TTY structure, containing buffers, etc.
*
* List of locks
* (t) locked by t_mtx
* (l) locked by tty_list_sx
* (c) const until freeing
*/
struct tty {
struct mtx *t_mtx; /* TTY lock. */
struct mtx t_mtxobj; /* Per-TTY lock (when not borrowing). */
TAILQ_ENTRY(tty) t_list; /* (l) TTY list entry. */
unsigned int t_flags; /* (t) Terminal option flags. */
/* Keep flags in sync with db_show_tty and pstat(8). */
#define TF_NOPREFIX 0x00001 /* Don't prepend "tty" to device name. */
#define TF_INITLOCK 0x00002 /* Create init/lock state devices. */
#define TF_CALLOUT 0x00004 /* Create "cua" devices. */
#define TF_OPENED_IN 0x00008 /* "tty" node is in use. */
#define TF_OPENED_OUT 0x00010 /* "cua" node is in use. */
#define TF_OPENED_CONS 0x00020 /* Device in use as console. */
#define TF_OPENED (TF_OPENED_IN|TF_OPENED_OUT|TF_OPENED_CONS)
#define TF_GONE 0x00040 /* Device node is gone. */
#define TF_OPENCLOSE 0x00080 /* Device is in open()/close(). */
#define TF_ASYNC 0x00100 /* Asynchronous I/O enabled. */
#define TF_LITERAL 0x00200 /* Accept the next character literally. */
#define TF_HIWAT_IN 0x00400 /* We've reached the input watermark. */
#define TF_HIWAT_OUT 0x00800 /* We've reached the output watermark. */
#define TF_HIWAT (TF_HIWAT_IN|TF_HIWAT_OUT)
#define TF_STOPPED 0x01000 /* Output flow control - stopped. */
#define TF_EXCLUDE 0x02000 /* Exclusive access. */
#define TF_BYPASS 0x04000 /* Optimized input path. */
#define TF_ZOMBIE 0x08000 /* Modem disconnect received. */
#define TF_HOOK 0x10000 /* TTY has hook attached. */
#define TF_BUSY_IN 0x20000 /* Process busy in read() -- not supported. */
#define TF_BUSY_OUT 0x40000 /* Process busy in write(). */
#define TF_BUSY (TF_BUSY_IN|TF_BUSY_OUT)
unsigned int t_revokecnt; /* (t) revoke() count. */
/* Buffering mechanisms. */
struct ttyinq t_inq; /* (t) Input queue. */
size_t t_inlow; /* (t) Input low watermark. */
struct ttyoutq t_outq; /* (t) Output queue. */
size_t t_outlow; /* (t) Output low watermark. */
/* Sleeping mechanisms. */
struct cv t_inwait; /* (t) Input wait queue. */
struct cv t_outwait; /* (t) Output wait queue. */
struct cv t_outserwait; /* (t) Serial output wait queue. */
struct cv t_bgwait; /* (t) Background wait queue. */
struct cv t_dcdwait; /* (t) Carrier Detect wait queue. */
/* Polling mechanisms. */
struct selinfo t_inpoll; /* (t) Input poll queue. */
struct selinfo t_outpoll; /* (t) Output poll queue. */
struct sigio *t_sigio; /* (t) Asynchronous I/O. */
struct termios t_termios; /* (t) I/O processing flags. */
struct winsize t_winsize; /* (t) Window size. */
unsigned int t_column; /* (t) Current cursor position. */
unsigned int t_writepos; /* (t) Where input was interrupted. */
int t_compatflags; /* (t) COMPAT_43TTY flags. */
/* Init/lock-state devices. */
struct termios t_termios_init_in; /* tty%s.init. */
struct termios t_termios_lock_in; /* tty%s.lock. */
struct termios t_termios_init_out; /* cua%s.init. */
struct termios t_termios_lock_out; /* cua%s.lock. */
struct ttydevsw *t_devsw; /* (c) Driver hooks. */
struct ttyhook *t_hook; /* (t) Capture/inject hook. */
/* Process signal delivery. */
struct pgrp *t_pgrp; /* (t) Foreground process group. */
struct session *t_session; /* (t) Associated session. */
unsigned int t_sessioncnt; /* (t) Backpointing sessions. */
void *t_devswsoftc; /* (c) Soft config, for drivers. */
void *t_hooksoftc; /* (t) Soft config, for hooks. */
struct cdev *t_dev; /* (c) Primary character device. */
};
/*
* Userland version of struct tty, for sysctl kern.ttys
*/
struct xtty {
size_t xt_size; /* Structure size. */
size_t xt_insize; /* Input queue size. */
size_t xt_incc; /* Canonicalized characters. */
size_t xt_inlc; /* Input line charaters. */
size_t xt_inlow; /* Input low watermark. */
size_t xt_outsize; /* Output queue size. */
size_t xt_outcc; /* Output queue usage. */
size_t xt_outlow; /* Output low watermark. */
unsigned int xt_column; /* Current column position. */
pid_t xt_pgid; /* Foreground process group. */
pid_t xt_sid; /* Session. */
unsigned int xt_flags; /* Terminal option flags. */
dev_t xt_dev; /* Userland device. */
};
#ifdef _KERNEL
/* Used to distinguish between normal, callout, lock and init devices. */
#define TTYUNIT_INIT 0x1
#define TTYUNIT_LOCK 0x2
#define TTYUNIT_CALLOUT 0x4
/* Allocation and deallocation. */
struct tty *tty_alloc(struct ttydevsw *tsw, void *softc);
struct tty *tty_alloc_mutex(struct ttydevsw *tsw, void *softc, struct mtx *mtx);
void tty_rel_pgrp(struct tty *tp, struct pgrp *pgrp);
void tty_rel_sess(struct tty *tp, struct session *sess);
void tty_rel_gone(struct tty *tp);
#define tty_lock(tp) mtx_lock((tp)->t_mtx)
#define tty_unlock(tp) mtx_unlock((tp)->t_mtx)
#define tty_lock_owned(tp) mtx_owned((tp)->t_mtx)
#define tty_lock_assert(tp,ma) mtx_assert((tp)->t_mtx, (ma))
#define tty_getlock(tp) ((tp)->t_mtx)
/* Device node creation. */
int tty_makedevf(struct tty *tp, struct ucred *cred, int flags,
const char *fmt, ...) __printflike(4, 5);
#define TTYMK_CLONING 0x1
#define tty_makedev(tp, cred, fmt, ...) \
(void )tty_makedevf((tp), (cred), 0, (fmt), ## __VA_ARGS__)
#define tty_makealias(tp,fmt,...) \
make_dev_alias((tp)->t_dev, fmt, ## __VA_ARGS__)
/* Signalling processes. */
void tty_signal_sessleader(struct tty *tp, int signal);
void tty_signal_pgrp(struct tty *tp, int signal);
/* Waking up readers/writers. */
int tty_wait(struct tty *tp, struct cv *cv);
int tty_wait_background(struct tty *tp, struct thread *td, int sig);
int tty_timedwait(struct tty *tp, struct cv *cv, int timo);
void tty_wakeup(struct tty *tp, int flags);
/* System messages. */
int tty_checkoutq(struct tty *tp);
int tty_putchar(struct tty *tp, char c);
int tty_ioctl(struct tty *tp, u_long cmd, void *data, int fflag,
struct thread *td);
int tty_ioctl_compat(struct tty *tp, u_long cmd, caddr_t data,
int fflag, struct thread *td);
void tty_set_winsize(struct tty *tp, const struct winsize *wsz);
void tty_init_console(struct tty *tp, speed_t speed);
void tty_flush(struct tty *tp, int flags);
void tty_hiwat_in_block(struct tty *tp);
void tty_hiwat_in_unblock(struct tty *tp);
dev_t tty_udev(struct tty *tp);
#define tty_opened(tp) ((tp)->t_flags & TF_OPENED)
#define tty_gone(tp) ((tp)->t_flags & TF_GONE)
#define tty_softc(tp) ((tp)->t_devswsoftc)
#define tty_devname(tp) devtoname((tp)->t_dev)
/* Status line printing. */
void tty_info(struct tty *tp);
/* /dev/console selection. */
void ttyconsdev_select(const char *name);
/* Pseudo-terminal hooks. */
int pts_alloc(int fflags, struct thread *td, struct file *fp);
int pts_alloc_external(int fd, struct thread *td, struct file *fp,
struct cdev *dev, const char *name);
/* Drivers and line disciplines also need to call these. */
#include <sys/ttydisc.h>
#include <sys/ttydevsw.h>
#include <sys/ttyhook.h>
#endif /* _KERNEL */
#endif /* !_SYS_TTY_H_ */
Reference in New Issue View Git Blame Copy Permalink