static void
mtustart(struct mt_softc *sc)
{
dlog(LOG_DEBUG, "%s ustart", device_xname(sc->sc_dev));
if (hpibreq(device_parent(sc->sc_dev), &sc->sc_hq))
mtstart(sc);
}
int
parrw(dev_t dev, register struct uio *uio)
{
int unit = UNIT(dev);
register struct par_softc *sc = getparsp(unit);
register int s, len, cnt;
register char *cp;
int error = 0, gotdata = 0;
int buflen;
char *buf;
len = 0;
cnt = 0;
if (!!(sc->sc_flags & PARF_OREAD) ^ (uio->uio_rw == UIO_READ))
return EINVAL;
if (uio->uio_resid == 0)
return(0);
#ifdef DEBUG
if (pardebug & (PDB_FOLLOW|PDB_IO))
printf("parrw(%llx, %p, %c): burst %d, timo %d, resid %x\n",
dev, uio, uio->uio_rw == UIO_READ ? 'R' : 'W',
sc->sc_burst, sc->sc_timo, uio->uio_resid);
#endif
buflen = min(sc->sc_burst, uio->uio_resid);
buf = (char *)malloc(buflen, M_DEVBUF, M_WAITOK);
sc->sc_flags |= PARF_UIO;
if (sc->sc_timo > 0)
{
sc->sc_flags |= PARF_TIMO;
callout_reset(&sc->sc_timo_ch, sc->sc_timo, partimo, sc);
}
while (uio->uio_resid > 0)
{
len = min(buflen, uio->uio_resid);
cp = buf;
if (uio->uio_rw == UIO_WRITE)
{
error = uiomove(cp, len, uio);
if (error)
break;
}
again:
#if 0
if ((sc->sc_flags & PARF_UIO) && hpibreq(&sc->sc_dq) == 0)
sleep(sc, PRIBIO+1);
#endif
/*
* Check if we timed out during sleep or uiomove
*/
s = splsoftclock();
if ((sc->sc_flags & PARF_UIO) == 0)
{
#ifdef DEBUG
if (pardebug & PDB_IO)
printf("parrw: uiomove/sleep timo, flags %x\n",
sc->sc_flags);
#endif
if (sc->sc_flags & PARF_TIMO)
{
callout_stop(&sc->sc_timo_ch);
sc->sc_flags &= ~PARF_TIMO;
}
splx(s);
break;
}
splx(s);
/*
* Perform the operation
*/
if (uio->uio_rw == UIO_WRITE)
cnt = parsend (cp, len);
else
cnt = parreceive (cp, len);
if (cnt < 0)
{
error = -cnt;
break;
}
s = splbio();
#if 0
hpibfree(&sc->sc_dq);
#endif
#ifdef DEBUG
if (pardebug & PDB_IO)
printf("parrw: %s(%p, %d) -> %d\n",
uio->uio_rw == UIO_READ ? "recv" : "send", cp, len, cnt);
#endif
splx(s);
if (uio->uio_rw == UIO_READ)
{
if (cnt)
{
error = uiomove(cp, cnt, uio);
if (error)
break;
gotdata++;
}
/*
* Didn't get anything this time, but did in the past.
* Consider us done.
*/
else if (gotdata)
break;
}
s = splsoftclock();
/*
* Operation timeout (or non-blocking), quit now.
*/
if ((sc->sc_flags & PARF_UIO) == 0)
{
#ifdef DEBUG
if (pardebug & PDB_IO)
printf("parrw: timeout/done\n");
#endif
splx(s);
break;
}
/*
* Implement inter-read delay
*/
if (sc->sc_delay > 0)
{
sc->sc_flags |= PARF_DELAY;
callout_reset(&sc->sc_start_ch, sc->sc_delay, parstart, sc);
error = tsleep(sc, PCATCH | (PZERO - 1), "par-cdelay", 0);
if (error)
{
splx(s);
break;
}
}
splx(s);
/*
* Must not call uiomove again til we've used all data
* that we already grabbed.
*/
if (uio->uio_rw == UIO_WRITE && cnt != len)
{
cp += cnt;
len -= cnt;
cnt = 0;
goto again;
}
}
s = splsoftclock();
if (sc->sc_flags & PARF_TIMO)
{
callout_stop(&sc->sc_timo_ch);
sc->sc_flags &= ~PARF_TIMO;
}
if (sc->sc_flags & PARF_DELAY)
{
callout_stop(&sc->sc_start_ch);
sc->sc_flags &= ~PARF_DELAY;
}
splx(s);
/*
* Adjust for those chars that we uiomove'ed but never wrote
*/
if (uio->uio_rw == UIO_WRITE && cnt != len)
{
uio->uio_resid += (len - cnt);
#ifdef DEBUG
if (pardebug & PDB_IO)
printf("parrw: short write, adjust by %d\n",
len-cnt);
#endif
}
free(buf, M_DEVBUF);
#ifdef DEBUG
if (pardebug & (PDB_FOLLOW|PDB_IO))
printf("parrw: return %d, resid %d\n", error, uio->uio_resid);
#endif
return (error);
}
