uda.c

早期freebsd实现

		 * it is nonexistent, or because it is spun down, or
		 * for some other reason.
		 */
		switch (mp->mscp_status & ~M_ST_MASK) {

		case M_OFFLINE_UNKNOWN:
			/*
			 * No such drive, and there are none with
			 * higher unit numbers either, if we are
			 * using M_GUM_NEXTUNIT.
			 */
			return (0);

		case M_OFFLINE_UNMOUNTED:
			/*
			 * The drive is not spun up.  Use it anyway.
			 *
			 * N.B.: this seems to be a common occurrance
			 * after a power failure.  The first attempt
			 * to bring it on line seems to spin it up
			 * (and thus takes several minutes).  Perhaps
			 * we should note here that the on-line may
			 * take longer than usual.
			 */
			break;

		default:
			/*
			 * In service, or something else equally unusable.
			 */
			printf("uda%d: unit %d off line: ", um->um_ctlr,
				mp->mscp_unit);
			mscp_printevent(mp);
			goto try_another;
		}
		break;

	default:
		printf("uda%d: unable to get unit status: ", um->um_ctlr);
		mscp_printevent(mp);
		return (0);
	}

	/*
	 * Does this ever happen?  What (if anything) does it mean?
	 */
	if (mp->mscp_unit < next) {
		printf("uda%d: unit %d, next %d\n",
			um->um_ctlr, mp->mscp_unit, next);
		return (0);
	}

	if (mp->mscp_unit >= MAXUNIT) {
		printf("uda%d: cannot handle unit number %d (max is %d)\n",
			um->um_ctlr, mp->mscp_unit, MAXUNIT - 1);
		return (0);
	}

	/*
	 * See if we already handle this drive.
	 * (Only likely if ui->ui_slave=='?'.)
	 */
	if (udaip[um->um_ctlr][mp->mscp_unit] != NULL) {
try_another:
		if (ui->ui_slave != '?')
			return (0);
		next = mp->mscp_unit + 1;
		goto findunit;
	}

	/*
	 * Voila!
	 */
	uda_rasave(ui->ui_unit, mp, 0);
	ui->ui_flags = 0;	/* not on line, nor anything else */
	ui->ui_slave = mp->mscp_unit;
	return (1);
}

/*
 * Attach a found slave.  Make sure the watchdog timer is running.
 * If this disk is being profiled, fill in the `wpms' value (used by
 * what?).  Set up the inverting pointer, and attempt to bring the
 * drive on line and read its label.
 */
udaattach(ui)
	register struct uba_device *ui;
{
	register int unit = ui->ui_unit;

	if (udawstart == 0) {
		timeout(udawatch, (caddr_t) 0, hz);
		udawstart++;
	}

	/*
	 * Floppies cannot be brought on line unless there is
	 * a disk in the drive.  Since an ONLINE while cold
	 * takes ten seconds to fail, and (when notyet becomes now)
	 * no sensible person will swap to one, we just
	 * defer the ONLINE until someone tries to use the drive.
	 *
	 * THIS ASSUMES THAT DRIVE TYPES ?X? ARE FLOPPIES
	 */
	if (MSCP_MID_ECH(1, ra_info[unit].ra_mediaid) == 'X' - '@') {
		printf(": floppy");
		return;
	}
	if (ui->ui_dk >= 0)
		dk_wpms[ui->ui_dk] = (60 * 31 * 256);	/* approx */
	udaip[ui->ui_ctlr][ui->ui_slave] = ui;

	if (uda_rainit(ui, 0))
		printf(": offline");
	else if (ra_info[unit].ra_state == OPEN) {
		printf(": %s, size = %d sectors",
		    udalabel[unit].d_typename, ra_info[unit].ra_dsize);
#ifdef notyet
		addswap(makedev(UDADEVNUM, udaminor(unit, 0)), &udalabel[unit]);
#endif
	}
}

/*
 * Initialise a UDA50.  Return true iff something goes wrong.
 */
udainit(ctlr)
	int ctlr;
{
	register struct uda_softc *sc;
	register struct udadevice *udaddr;
	struct uba_ctlr *um;
	int timo, ubinfo;

	sc = &uda_softc[ctlr];
	um = udaminfo[ctlr];
	if ((sc->sc_flags & SC_MAPPED) == 0) {
		/*
		 * Map the communication area and command and
		 * response packets into Unibus space.
		 */
		ubinfo = uballoc(um->um_ubanum, (caddr_t) &uda[ctlr],
			sizeof (struct uda), UBA_CANTWAIT);
		if (ubinfo == 0) {
			printf("uda%d: uballoc map failed\n", ctlr);
			return (-1);
		}
		sc->sc_uda = (struct uda *) UBAI_ADDR(ubinfo);
		sc->sc_flags |= SC_MAPPED;
	}

	/*
	 * While we are thinking about it, reset the next command
	 * and response indicies.
	 */
	sc->sc_mi.mi_cmd.mri_next = 0;
	sc->sc_mi.mi_rsp.mri_next = 0;

	/*
	 * Start up the hardware initialisation sequence.
	 */
#define	STEP0MASK	(UDA_ERR | UDA_STEP4 | UDA_STEP3 | UDA_STEP2 | \
			 UDA_STEP1 | UDA_NV)

	sc->sc_state = ST_IDLE;	/* in case init fails */
	udaddr = (struct udadevice *)um->um_addr;
	udaddr->udaip = 0;
	timo = todr() + 1000;
	while ((udaddr->udasa & STEP0MASK) == 0) {
		if (todr() > timo) {
			printf("uda%d: timeout during init\n", ctlr);
			return (-1);
		}
	}
	if ((udaddr->udasa & STEP0MASK) != UDA_STEP1) {
		printf("uda%d: init failed, sa=%b\n", ctlr,
			udaddr->udasa, udasr_bits);
		udasaerror(um, 0);
		return (-1);
	}

	/*
	 * Success!  Record new state, and start step 1 initialisation.
	 * The rest is done in the interrupt handler.
	 */
	sc->sc_state = ST_STEP1;
	udaddr->udasa = UDA_ERR | (NCMDL2 << 11) | (NRSPL2 << 8) | UDA_IE |
	    (sc->sc_ivec >> 2);
	return (0);
}

/*
 * Open a drive.
 */
/*ARGSUSED*/
udaopen(dev, flag, fmt)
	dev_t dev;
	int flag, fmt;
{
	register int unit;
	register struct uba_device *ui;
	register struct uda_softc *sc;
	register struct disklabel *lp;
	register struct partition *pp;
	register struct ra_info *ra;
	int s, i, part, mask, error = 0;
	daddr_t start, end;

	/*
	 * Make sure this is a reasonable open request.
	 */
	unit = udaunit(dev);
	if (unit >= NRA || (ui = udadinfo[unit]) == 0 || ui->ui_alive == 0)
		return (ENXIO);

	/*
	 * Make sure the controller is running, by (re)initialising it if
	 * necessary.
	 */
	sc = &uda_softc[ui->ui_ctlr];
	s = spl5();
	if (sc->sc_state != ST_RUN) {
		if (sc->sc_state == ST_IDLE && udainit(ui->ui_ctlr)) {
			splx(s);
			return (EIO);
		}
		/*
		 * In case it does not come up, make sure we will be
		 * restarted in 10 seconds.  This corresponds to the
		 * 10 second timeouts in udaprobe() and udaslave().
		 */
		sc->sc_flags |= SC_DOWAKE;
		timeout(wakeup, (caddr_t) sc, 10 * hz);
		sleep((caddr_t) sc, PRIBIO);
		if (sc->sc_state != ST_RUN) {
			splx(s);
			printf("uda%d: controller hung\n", ui->ui_ctlr);
			return (EIO);
		}
		untimeout(wakeup, (caddr_t) sc);
	}

	/*
	 * Wait for the state to settle
	 */
	ra = &ra_info[unit];
	while (ra->ra_state != OPEN && ra->ra_state != OPENRAW &&
	    ra->ra_state != CLOSED)
		if (error = tsleep((caddr_t)ra, (PZERO + 1) | PCATCH,
		    devopn, 0)) {
			splx(s);
			return (error);
		}

	/*
	 * If not on line, or we are not sure of the label, reinitialise
	 * the drive.
	 */
	if ((ui->ui_flags & UNIT_ONLINE) == 0 ||
	    (ra->ra_state != OPEN && ra->ra_state != OPENRAW))
		error = uda_rainit(ui, flag);
	splx(s);
	if (error)
		return (error);

	part = udapart(dev);
	lp = &udalabel[unit];
	if (part >= lp->d_npartitions)
		return (ENXIO);
	/*
	 * Warn if a partition is opened that overlaps another
	 * already open, unless either is the `raw' partition
	 * (whole disk).
	 */
#define	RAWPART		2	/* 'c' partition */	/* XXX */
	mask = 1 << part;
	if ((ra->ra_openpart & mask) == 0 && part != RAWPART) {
		pp = &lp->d_partitions[part];
		start = pp->p_offset;
		end = pp->p_offset + pp->p_size;
		for (pp = lp->d_partitions, i = 0;
		     i < lp->d_npartitions; pp++, i++) {
			if (pp->p_offset + pp->p_size <= start ||
			    pp->p_offset >= end || i == RAWPART)
				continue;
			if (ra->ra_openpart & (1 << i))
				log(LOG_WARNING,
				    "ra%d%c: overlaps open partition (%c)\n",
				    unit, part + 'a', i + 'a');
		}
	}
	switch (fmt) {
	case S_IFCHR:
		ra->ra_copenpart |= mask;
		break;
	case S_IFBLK:
		ra->ra_bopenpart |= mask;
		break;
	}
	ra->ra_openpart |= mask;
	return (0);
}

/* ARGSUSED */
udaclose(dev, flags, fmt)
	dev_t dev;
	int flags, fmt;
{
	register int unit = udaunit(dev);
	register struct ra_info *ra = &ra_info[unit];
	int s, mask = (1 << udapart(dev));

	switch (fmt) {
	case S_IFCHR:
		ra->ra_copenpart &= ~mask;
		break;
	case S_IFBLK:
		ra->ra_bopenpart &= ~mask;
		break;
	}
	ra->ra_openpart = ra->ra_copenpart | ra->ra_bopenpart;

	/*
	 * Should wait for I/O to complete on this partition even if
	 * others are open, but wait for work on blkflush().
	 */
	if (ra->ra_openpart == 0) {
		s = spl5();
		while (udautab[unit].b_actf)
			sleep((caddr_t)&udautab[unit], PZERO - 1);
		splx(s);
		ra->ra_state = CLOSED;
		ra->ra_wlabel = 0;
	}
	return (0);
}

/*
 * Initialise a drive.  If it is not already, bring it on line,
 * and set a timeout on it in case it fails to respond.
 * When on line, read in the pack label.
 */
uda_rainit(ui, flags)
	register struct uba_device *ui;
	int flags;
{
	register struct uda_softc *sc = &uda_softc[ui->ui_ctlr];
	register struct disklabel *lp;
	register struct mscp *mp;
	register int unit = ui->ui_unit;
	register struct ra_info *ra;
	char *msg, *readdisklabel();
	int s, i, udastrategy();
	extern int cold;

	ra = &ra_info[unit];
	if ((ui->ui_flags & UNIT_ONLINE) == 0) {
		mp = mscp_getcp(&sc->sc_mi, MSCP_WAIT);
		mp->mscp_opcode = M_OP_ONLINE;
		mp->mscp_unit = ui->ui_slave;
		mp->mscp_cmdref = (long)&ui->ui_flags;
		*mp->mscp_addr |= MSCP_OWN | MSCP_INT;
		ra->ra_state = WANTOPEN;
		if (!cold)
			s = spl5();
		i = ((struct udadevice *)ui->ui_addr)->udaip;

		if (cold) {
			i = todr() + 1000;
			while ((ui->ui_flags & UNIT_ONLINE) == 0)
				if (todr() > i)
					break;
		} else {
			timeout(wakeup, (caddr_t)&ui->ui_flags, 10 * hz);
			sleep((caddr_t)&ui->ui_flags, PSWP + 1);
			splx(s);
			untimeout(wakeup, (caddr_t)&ui->ui_flags);
		}
		if (ra->ra_state != OPENRAW) {
			ra->ra_state = CLOSED;
			wakeup((caddr_t)ra);
			return (EIO);
		}
	}

	lp = &udalabel[unit];
	lp->d_secsize = DEV_BSIZE;
	lp->d_secperunit = ra->ra_dsize;

	if (flags & O_NDELAY)
		return (0);
	ra->ra_state = RDLABEL;
	/*
	 * Set up default sizes until we have the label, or longer
	 * if there is none.  Set secpercyl, as readdisklabel wants
	 * to compute b_cylin (although we do not need it), and set
	 * nsectors in case diskerr is called.
	 */
	lp->d_secpercyl = 1;
	lp->d_npartitions = 1;
	lp->d_secsize = 512;
	lp->d_secperunit = ra->ra_dsize;
	lp->d_nsectors = ra->ra_geom.rg_nsectors;
	lp->d_partitions[0].p_size = lp->d_secperunit;
	lp->d_partitions[0].p_offset = 0;

	/*
	 * Read pack label.
	 */
	if ((msg = readdisklabel(udaminor(unit, 0), udastrategy, lp)) != NULL) {
		if (cold)
			printf(": %s", msg);
		else
			log(LOG_ERR, "ra%d: %s", unit, msg);
#ifdef COMPAT_42
		if (udamaptype(unit, lp))
			ra->ra_state = OPEN;
		else
			ra->ra_state = OPENRAW;
#else
		ra->ra_state = OPENRAW;
		uda_makefakelabel(ra, lp);
#endif
	} else
		ra->ra_state = OPEN;
	wakeup((caddr_t)ra);
	return (0);
}

/*
 * Copy the geometry information for the given ra from a
 * GET UNIT STATUS response.  If check, see if it changed.
 */
uda_rasave(unit, mp, check)
	int unit;
	register struct mscp *mp;
	int check;
{
	register struct ra_info *ra = &ra_info[unit];

	if (check && ra->ra_mediaid != mp->mscp_guse.guse_mediaid) {
		printf("ra%d: changed types! was %d now %d\n", unit,
			ra->ra_mediaid, mp->mscp_guse.guse_mediaid);
		ra->ra_state = CLOSED;	/* ??? */
	}
	/* ra->ra_type = mp->mscp_guse.guse_drivetype; */
	ra->ra_mediaid = mp->mscp_guse.guse_mediaid;
	ra->ra_geom.rg_nsectors = mp->mscp_guse.guse_nspt;
	ra->ra_geom.rg_ngroups = mp->mscp_guse.guse_group;
	ra->ra_geom.rg_ngpc = mp->mscp_guse.guse_ngpc;
	ra->ra_geom.rg_ntracks = ra->ra_geom.rg_ngroups * ra->ra_geom.rg_ngpc;
	/* ra_geom.rg_ncyl cannot be computed until we have ra_dsize */
#ifdef notyet
	ra->ra_geom.rg_rctsize = mp->mscp_guse.guse_rctsize;
	ra->ra_geom.rg_rbns = mp->mscp_guse.guse_nrpt;
	ra->ra_geom.rg_nrct = mp->mscp_guse.guse_nrct;
#endif
}

/*
 * Queue a transfer request, and if possible, hand it to the controller.
 *