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freebsd/sys/dev/nmdm/nmdm.c
Poul-Henning Kamp 8e1f1df080 Device megapatch 3/6:
Add missing D_TTY flags to various drivers.

Complete asserts that dev_t's passed to ttyread(), ttywrite(),
ttypoll() and ttykqwrite() have (d_flags & D_TTY) and a struct tty
pointer.

Make ttyread(), ttywrite(), ttypoll() and ttykqwrite() the default
cdevsw methods for D_TTY drivers and remove the explicit initializations
in various drivers cdevsw structures.
2004-02-21 20:41:11 +00:00

619 lines
15 KiB
C

/*
* Copyright (c) 1982, 1986, 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Pseudo-nulmodem driver
* Mighty handy for use with serial console in Vmware
*/
#include "opt_compat.h"
#include "opt_tty.h"
#include <sys/param.h>
#include <sys/systm.h>
#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
#include <sys/ioctl_compat.h>
#endif
#include <sys/proc.h>
#include <sys/tty.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <sys/poll.h>
#include <sys/kernel.h>
#include <sys/vnode.h>
#include <sys/signalvar.h>
#include <sys/malloc.h>
MALLOC_DEFINE(M_NLMDM, "nullmodem", "nullmodem data structures");
static void nmdmstart(struct tty *tp);
static void nmdmstop(struct tty *tp, int rw);
static void wakeup_other(struct tty *tp, int flag);
static void nmdminit(dev_t dev);
static d_open_t nmdmopen;
static d_close_t nmdmclose;
static d_read_t nmdmread;
static d_write_t nmdmwrite;
static d_ioctl_t nmdmioctl;
static struct cdevsw nmdm_cdevsw = {
.d_open = nmdmopen,
.d_close = nmdmclose,
.d_read = nmdmread,
.d_write = nmdmwrite,
.d_ioctl = nmdmioctl,
.d_name = "nmdm",
.d_flags = D_TTY | D_PSEUDO,
};
#define BUFSIZ 100 /* Chunk size iomoved to/from user */
#define NMDM_MAX_NUM 128 /* Artificially limit # devices. */
#define PF_STOPPED 0x10 /* user told stopped */
#define BFLAG CLONE_FLAG0
struct softpart {
struct tty nm_tty;
dev_t dev;
int modemsignals; /* bits defined in sys/ttycom.h */
int gotbreak;
};
struct nm_softc {
TAILQ_ENTRY(nm_softc) pt_list;
int pt_flags;
struct softpart part1, part2;
struct prison *pt_prison;
};
static struct clonedevs *nmdmclones;
static TAILQ_HEAD(,nm_softc) nmdmhead = TAILQ_HEAD_INITIALIZER(nmdmhead);
static void
nmdm_clone(void *arg, char *name, int nameen, dev_t *dev)
{
int i, unit;
char *p;
dev_t d1, d2;
if (*dev != NODEV)
return;
if (strcmp(name, "nmdm") == 0) {
p = NULL;
unit = -1;
} else {
i = dev_stdclone(name, &p, "nmdm", &unit);
if (i == 0)
return;
if (p[0] != '\0' && p[0] != 'A' && p[0] != 'B')
return;
else if (p[0] != '\0' && p[1] != '\0')
return;
}
i = clone_create(&nmdmclones, &nmdm_cdevsw, &unit, &d1, 0);
if (i) {
d1 = make_dev(&nmdm_cdevsw, unit2minor(unit),
0, 0, 0666, "nmdm%dA", unit);
if (d1 == NULL)
return;
d2 = make_dev(&nmdm_cdevsw, unit2minor(unit) | BFLAG,
0, 0, 0666, "nmdm%dB", unit);
if (d2 == NULL) {
destroy_dev(d1);
return;
}
d2->si_drv2 = d1;
d1->si_drv2 = d2;
dev_depends(d1, d2);
dev_depends(d2, d1);
d1->si_flags |= SI_CHEAPCLONE;
d2->si_flags |= SI_CHEAPCLONE;
}
if (p != NULL && p[0] == 'B')
*dev = d1->si_drv2;
else
*dev = d1;
}
static void
nmdm_crossover(struct nm_softc *pti,
struct softpart *ourpart,
struct softpart *otherpart);
#define GETPARTS(tp, ourpart, otherpart) \
do { \
struct nm_softc *pti = tp->t_dev->si_drv1; \
if (tp == &pti->part1.nm_tty) { \
ourpart = &pti->part1; \
otherpart = &pti->part2; \
} else { \
ourpart = &pti->part2; \
otherpart = &pti->part1; \
} \
} while (0)
/*
* This function creates and initializes a pair of ttys.
*/
static void
nmdminit(dev_t dev1)
{
dev_t dev2;
struct nm_softc *pt;
dev2 = dev1->si_drv2;
dev1->si_flags &= ~SI_CHEAPCLONE;
dev2->si_flags &= ~SI_CHEAPCLONE;
pt = malloc(sizeof(*pt), M_NLMDM, M_WAITOK | M_ZERO);
TAILQ_INSERT_TAIL(&nmdmhead, pt, pt_list);
dev1->si_drv1 = dev2->si_drv1 = pt;
pt->part1.dev = dev1;
pt->part2.dev = dev2;
dev1->si_tty = &pt->part1.nm_tty;
dev2->si_tty = &pt->part2.nm_tty;
ttyregister(&pt->part1.nm_tty);
ttyregister(&pt->part2.nm_tty);
pt->part1.nm_tty.t_oproc = nmdmstart;
pt->part2.nm_tty.t_oproc = nmdmstart;
pt->part1.nm_tty.t_stop = nmdmstop;
pt->part2.nm_tty.t_stop = nmdmstop;
pt->part2.nm_tty.t_dev = dev1;
pt->part1.nm_tty.t_dev = dev2;
}
/*
* Device opened from userland
*/
static int
nmdmopen(dev_t dev, int flag, int devtype, struct thread *td)
{
register struct tty *tp, *tp2;
int error;
struct nm_softc *pti;
struct softpart *ourpart, *otherpart;
if (dev->si_drv1 == NULL)
nmdminit(dev);
pti = dev->si_drv1;
if (minor(dev) & BFLAG)
tp = &pti->part2.nm_tty;
else
tp = &pti->part1.nm_tty;
GETPARTS(tp, ourpart, otherpart);
tp2 = &otherpart->nm_tty;
ourpart->modemsignals |= TIOCM_LE;
if ((tp->t_state & TS_ISOPEN) == 0) {
ttychars(tp); /* Set up default chars */
tp->t_iflag = TTYDEF_IFLAG;
tp->t_oflag = TTYDEF_OFLAG;
tp->t_lflag = TTYDEF_LFLAG;
tp->t_cflag = TTYDEF_CFLAG;
tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
} else if (tp->t_state & TS_XCLUDE && suser(td)) {
return (EBUSY);
} else if (pti->pt_prison != td->td_ucred->cr_prison) {
return (EBUSY);
}
/*
* If the other side is open we have carrier
*/
if (tp2->t_state & TS_ISOPEN) {
(void)(*linesw[tp->t_line].l_modem)(tp, 1);
}
/*
* And the other side gets carrier as we are now open.
*/
(void)(*linesw[tp2->t_line].l_modem)(tp2, 1);
/* External processing makes no sense here */
tp->t_lflag &= ~EXTPROC;
/*
* Wait here if we don't have carrier.
*/
#if 0
while ((tp->t_state & TS_CARR_ON) == 0) {
if (flag & FNONBLOCK)
break;
error = ttysleep(tp, TSA_CARR_ON(tp), TTIPRI | PCATCH,
"nmdopn", 0);
if (error)
return (error);
}
#endif
/*
* Give the line disciplin a chance to set this end up.
*/
error = (*linesw[tp->t_line].l_open)(dev, tp);
/*
* Wake up the other side.
* Theoretically not needed.
*/
ourpart->modemsignals |= TIOCM_DTR;
nmdm_crossover(pti, ourpart, otherpart);
if (error == 0)
wakeup_other(tp, FREAD|FWRITE); /* XXX */
return (error);
}
/*
* Device closed again
*/
static int
nmdmclose(dev_t dev, int flag, int mode, struct thread *td)
{
register struct tty *tp, *tp2;
int err;
struct softpart *ourpart, *otherpart;
/*
* let the other end know that the game is up
*/
tp = dev->si_tty;
GETPARTS(tp, ourpart, otherpart);
tp2 = &otherpart->nm_tty;
(void)(*linesw[tp2->t_line].l_modem)(tp2, 0);
/*
* XXX MDMBUF makes no sense for nmdms but would inhibit the above
* l_modem(). CLOCAL makes sense but isn't supported. Special
* l_modem()s that ignore carrier drop make no sense for nmdms but
* may be in use because other parts of the line discipline make
* sense for nmdms. Recover by doing everything that a normal
* ttymodem() would have done except for sending a SIGHUP.
*/
if (tp2->t_state & TS_ISOPEN) {
tp2->t_state &= ~(TS_CARR_ON | TS_CONNECTED);
tp2->t_state |= TS_ZOMBIE;
ttyflush(tp2, FREAD | FWRITE);
}
err = (*linesw[tp->t_line].l_close)(tp, flag);
ourpart->modemsignals &= ~TIOCM_DTR;
nmdm_crossover(dev->si_drv1, ourpart, otherpart);
nmdmstop(tp, FREAD|FWRITE);
(void) ttyclose(tp);
return (err);
}
/*
* handle read(2) request from userland
*/
static int
nmdmread(dev_t dev, struct uio *uio, int flag)
{
int error = 0;
struct tty *tp, *tp2;
struct softpart *ourpart, *otherpart;
tp = dev->si_tty;
GETPARTS(tp, ourpart, otherpart);
tp2 = &otherpart->nm_tty;
#if 0
if (tp2->t_state & TS_ISOPEN) {
error = (*linesw[tp->t_line].l_read)(tp, uio, flag);
wakeup_other(tp, FWRITE);
} else {
if (flag & IO_NDELAY) {
return (EWOULDBLOCK);
}
error = tsleep(TSA_PTC_READ(tp),
TTIPRI | PCATCH, "nmdout", 0);
}
}
#else
if ((error = (*linesw[tp->t_line].l_read)(tp, uio, flag)) == 0)
wakeup_other(tp, FWRITE);
#endif
return (error);
}
/*
* Write to pseudo-tty.
* Wakeups of controlling tty will happen
* indirectly, when tty driver calls nmdmstart.
*/
static int
nmdmwrite(dev_t dev, struct uio *uio, int flag)
{
register u_char *cp = 0;
register int cc = 0;
u_char locbuf[BUFSIZ];
int cnt = 0;
int error = 0;
struct tty *tp1, *tp;
struct softpart *ourpart, *otherpart;
tp1 = dev->si_tty;
/*
* Get the other tty struct.
* basically we are writing into the INPUT side of the other device.
*/
GETPARTS(tp1, ourpart, otherpart);
tp = &otherpart->nm_tty;
again:
if ((tp->t_state & TS_ISOPEN) == 0)
return (EIO);
while (uio->uio_resid > 0 || cc > 0) {
/*
* Fill up the buffer if it's empty
*/
if (cc == 0) {
cc = min(uio->uio_resid, BUFSIZ);
cp = locbuf;
error = uiomove((caddr_t)cp, cc, uio);
if (error)
return (error);
/* check again for safety */
if ((tp->t_state & TS_ISOPEN) == 0) {
/* adjust for data copied in but not written */
uio->uio_resid += cc;
return (EIO);
}
}
while (cc > 0) {
if (((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= (TTYHOG-2))
&& ((tp->t_canq.c_cc > 0) || !(tp->t_iflag&ICANON))) {
/*
* Come here to wait for space in outq,
* or space in rawq, or an empty canq.
*/
wakeup(TSA_HUP_OR_INPUT(tp));
if ((tp->t_state & TS_CONNECTED) == 0) {
/*
* Data piled up because not connected.
* Adjust for data copied in but
* not written.
*/
uio->uio_resid += cc;
return (EIO);
}
if (flag & IO_NDELAY) {
/*
* Don't wait if asked not to.
* Adjust for data copied in but
* not written.
*/
uio->uio_resid += cc;
if (cnt == 0)
return (EWOULDBLOCK);
return (0);
}
error = tsleep(TSA_PTC_WRITE(tp),
TTOPRI | PCATCH, "nmdout", 0);
if (error) {
/*
* Tsleep returned (signal?).
* Go find out what the user wants.
* adjust for data copied in but
* not written
*/
uio->uio_resid += cc;
return (error);
}
goto again;
}
(*linesw[tp->t_line].l_rint)(*cp++, tp);
cnt++;
cc--;
}
cc = 0;
}
return (0);
}
/*
* Start output on pseudo-tty.
* Wake up process selecting or sleeping for input from controlling tty.
*/
static void
nmdmstart(struct tty *tp)
{
register struct nm_softc *pti = tp->t_dev->si_drv1;
if (tp->t_state & TS_TTSTOP)
return;
pti->pt_flags &= ~PF_STOPPED;
wakeup_other(tp, FREAD);
}
/* Wakes up the OTHER tty;*/
static void
wakeup_other(struct tty *tp, int flag)
{
struct softpart *ourpart, *otherpart;
GETPARTS(tp, ourpart, otherpart);
if (flag & FREAD) {
selwakeuppri(&otherpart->nm_tty.t_rsel, TTIPRI);
wakeup(TSA_PTC_READ((&otherpart->nm_tty)));
}
if (flag & FWRITE) {
selwakeuppri(&otherpart->nm_tty.t_wsel, TTOPRI);
wakeup(TSA_PTC_WRITE((&otherpart->nm_tty)));
}
}
/*
* stopped output on tty, called when device is closed
*/
static void
nmdmstop(register struct tty *tp, int flush)
{
struct nm_softc *pti = tp->t_dev->si_drv1;
int flag;
/* note: FLUSHREAD and FLUSHWRITE already ok */
if (flush == 0) {
flush = TIOCPKT_STOP;
pti->pt_flags |= PF_STOPPED;
} else
pti->pt_flags &= ~PF_STOPPED;
/* change of perspective */
flag = 0;
if (flush & FREAD)
flag |= FWRITE;
if (flush & FWRITE)
flag |= FREAD;
wakeup_other(tp, flag);
}
/*
* handle ioctl(2) request from userland
*/
static int
nmdmioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct thread *td)
{
register struct tty *tp = dev->si_tty;
struct nm_softc *pti = dev->si_drv1;
int error, s;
register struct tty *tp2;
struct softpart *ourpart, *otherpart;
s = spltty();
GETPARTS(tp, ourpart, otherpart);
tp2 = &otherpart->nm_tty;
error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, td);
if (error == ENOIOCTL)
error = ttioctl(tp, cmd, data, flag);
if (error == ENOIOCTL) {
switch (cmd) {
case TIOCSBRK:
otherpart->gotbreak = 1;
break;
case TIOCCBRK:
break;
case TIOCSDTR:
ourpart->modemsignals |= TIOCM_DTR;
break;
case TIOCCDTR:
ourpart->modemsignals &= TIOCM_DTR;
break;
case TIOCMSET:
ourpart->modemsignals = *(int *)data;
otherpart->modemsignals = *(int *)data;
break;
case TIOCMBIS:
ourpart->modemsignals |= *(int *)data;
break;
case TIOCMBIC:
ourpart->modemsignals &= ~(*(int *)data);
otherpart->modemsignals &= ~(*(int *)data);
break;
case TIOCMGET:
*(int *)data = ourpart->modemsignals;
break;
case TIOCMSDTRWAIT:
break;
case TIOCMGDTRWAIT:
*(int *)data = 0;
break;
case TIOCTIMESTAMP:
/* FALLTHROUGH */
case TIOCDCDTIMESTAMP:
default:
splx(s);
error = ENOTTY;
return (error);
}
error = 0;
nmdm_crossover(pti, ourpart, otherpart);
}
splx(s);
return (error);
}
static void
nmdm_crossover(struct nm_softc *pti, struct softpart *ourpart,
struct softpart *otherpart)
{
otherpart->modemsignals &= ~(TIOCM_CTS|TIOCM_CAR);
if (ourpart->modemsignals & TIOCM_RTS)
otherpart->modemsignals |= TIOCM_CTS;
if (ourpart->modemsignals & TIOCM_DTR)
otherpart->modemsignals |= TIOCM_CAR;
}
/*
* Module handling
*/
static int
nmdm_modevent(module_t mod, int type, void *data)
{
static eventhandler_tag tag;
struct nm_softc *pt, *tpt;
int error = 0;
switch(type) {
case MOD_LOAD:
tag = EVENTHANDLER_REGISTER(dev_clone, nmdm_clone, 0, 1000);
if (tag == NULL)
return (ENOMEM);
break;
case MOD_SHUTDOWN:
/* FALLTHROUGH */
case MOD_UNLOAD:
EVENTHANDLER_DEREGISTER(dev_clone, tag);
TAILQ_FOREACH_SAFE(pt, &nmdmhead, pt_list, tpt) {
destroy_dev(pt->part1.dev);
TAILQ_REMOVE(&nmdmhead, pt, pt_list);
free(pt, M_NLMDM);
}
clone_cleanup(&nmdmclones);
break;
default:
error = EOPNOTSUPP;
}
return (error);
}
DEV_MODULE(nmdm, nmdm_modevent, NULL);