sd.c

早期freebsd实现

{
	register struct sd_softc *sc = &sd_softc[unit];
	register struct hp_device *hp = sc->sc_hd;

	if (hp->hp_dk >= 0) {
		dk_busy |= 1 << hp->hp_dk;
	}

	scstart(hp->hp_ctlr);
}


/*
 * Return:
 *	0	if not really an error
 *	<0	if we should do a retry
 *	>0	if a fatal error
 */
static int
sderror(unit, sc, hp, stat)
	int unit, stat;
	register struct sd_softc *sc;
	register struct hp_device *hp;
{
	int cond = 1;

	sdsense[unit].status = stat;
	if (stat & STS_CHECKCOND) {
		struct scsi_xsense *sp;

		sc_request_sense(hp->hp_ctlr, hp->hp_slave,
				   sc->sc_punit, sdsense[unit].sense,
				   sizeof(sdsense[unit].sense));
		sp = (struct scsi_xsense *)sdsense[unit].sense;
		printf("sd%d: scsi sense class %d, code %d", unit,
			sp->class, sp->code);
		if (sp->class == 7) {
			printf(", key %d", sp->key);
			if (sp->valid)
				printf(", blk %d", *(int *)&sp->info1);
			switch (sp->key) {
			/* no sense, try again */
			case 0:
				cond = -1;
				break;
			/* recovered error, not a problem */
			case 1:
				cond = 0;
				break;
			}
		}
		printf("\n");
	}
	return(cond);
}

/*
 * Interrupt
 */

int
sdintr(unit, stat)
	register int unit;
	int stat;
{
	register struct sd_softc *sc = &sd_softc[unit];
	register struct hp_device *hp = sc->sc_hd;
	register struct scsi_queue *dq = &sc->sc_dq;
	register struct buf *bp = dq->dq_bp;
	int cond;

	if (stat == SC_IO_TIMEOUT) {
		printf("sdintr: sd%d timeout error\n", unit, stat);
	}

	if (hp->hp_dk >= 0) {
		dk_busy &=~ (1 << hp->hp_dk);
		if (stat == 0) {
			++dk_seek[hp->hp_dk];
			++dk_xfer[hp->hp_dk];
			dk_wds[hp->hp_dk] += bp->b_bcount >> 6;
		}
	}

	if (bp->b_flags & B_READ) {
		sd_iostat[unit].imin = min(dq->dq_imin, sd_iostat[unit].imin);
		if (dq->dq_imax > sd_iostat[unit].imax) {
			sd_iostat[unit].imax = dq->dq_imax;
#ifdef SD_IOSTAT
			printf("sdintr: sd%d  INPUT	MAX = %d, MIN = %d\n",
			       unit, sd_iostat[unit].imax, sd_iostat[unit].imin);
#endif
		}
	} else {
		sd_iostat[unit].omin = min(dq->dq_omin, sd_iostat[unit].omin);
		if (dq->dq_omax > sd_iostat[unit].omax) {
			sd_iostat[unit].omax = dq->dq_omax;
#ifdef SD_IOSTAT
			printf("sdintr: sd%d  OUTPUT	MAX = %d, MIN = %d\n",
			       unit, sd_iostat[unit].omax, sd_iostat[unit].omin);
#endif
		}
	}

	if (stat != 0) {
		if (stat > 0) {
#ifdef DEBUGPRINT
			dbgprintall();
			printf("\n");
#endif
			cond = sderror(unit, sc, hp, stat);
			if (cond) {
				if (cond < 0 && sdtab[unit].b_errcnt++ < SDRETRY) {
					sdstart(unit);
					return;
				}
			}
		} else {
			if (sdtab[unit].b_errcnt++ < SDRETRY) {
				printf("sdintr: sd%d restart IO request\n", unit);
				sdstart(unit);
				return;
			}
		}
		bp->b_flags |= B_ERROR;
		bp->b_error = EIO;
	}

	sdtab[unit].b_errcnt = 0;
	sdtab[unit].b_actf = bp->b_actf;

	bp->b_resid = 0;

	biodone(bp);

	scfree(dq);

	if (sdtab[unit].b_actf) {
		sdustart(unit);
	} else {
		sdtab[unit].b_active = 0;
	}
}


/*
 * RAW Device Routines
 */

int
sdread(dev, uio, flags)
	dev_t dev;
	struct uio *uio;
	int flags;
{
	register int unit = sdunit(dev);

	return (physio(sdstrategy, NULL, dev, B_READ, minphys, uio));
}

int
sdwrite(dev, uio, flags)
	dev_t dev;
	struct uio *uio;
	int flags;
{
	register int unit = sdunit(dev);

	return (physio(sdstrategy, NULL, dev, B_WRITE, minphys, uio));
}

int
sdioctl(dev, cmd, data, flag, p)
	dev_t dev;
	int cmd;
	caddr_t data;
	int flag;
	struct proc *p;
{
	int unit = sdunit(dev);
	register struct sd_softc *sc = &sd_softc[unit];
	register struct disklabel *lp = &sdlabel[unit];
	int error = 0;

	switch (cmd) {

	case DIOCGDINFO:
		*(struct disklabel *)data = *lp;
		break;

	case DIOCGPART:
		((struct partinfo *)data)->disklab = lp;
		((struct partinfo *)data)->part =
		    &lp->d_partitions[sdpart(dev)];
		break;

        case DIOCWLABEL:
        case DIOCSDINFO:
        case DIOCWDINFO:
		break;

	default:
		error = ENOTTY;
		break;
	}
	return (error);
}


/*
 * Size
 */

int
sdsize(dev)
	dev_t dev;
{
	register int unit = sdunit(dev);
	register struct sd_softc *sc = &sd_softc[unit];

	if (unit >= NSD || (sc->sc_flags & SDF_ALIVE) == 0)
		return(-1);

	return(sdlabel[unit].d_partitions[sdpart(dev)].p_size);
}


/*
 * Dump
 */

int
sddump(dev)
	dev_t dev;
{
}

/*
 * Disk Subs
 */

/*
 * Attempt to read a disk label from a device
 * using the indicated stategy routine.
 * The label must be partly set up before this:
 * secpercyl and anything required in the strategy routine
 * (e.g., sector size) must be filled in before calling us.
 * Returns null on success and an error string on failure.
 */
char *
sdreadlabel(dev, strat, lp)
	dev_t dev;
	int (*strat)();
	register struct disklabel *lp;
{
	register struct buf *bp;
	struct disklabel *dlp;
	char *msg = NULL;

	if (lp->d_secperunit == 0)
		lp->d_secperunit = 0x1fffffff;
	lp->d_npartitions = 1;
	if (lp->d_partitions[0].p_size == 0)
		lp->d_partitions[0].p_size = 0x1fffffff;
	lp->d_partitions[0].p_offset = 0;

	bp = geteblk((int)lp->d_secsize);
	bp->b_dev = dev;
	bp->b_blkno = LABELSECTOR;
	bp->b_bcount = lp->d_secsize;
	bp->b_flags = B_BUSY | B_READ;
	(*strat)(bp);
	if (biowait(bp)) {
		msg = "I/O error";
	} else {
		for (dlp = (struct disklabel *)bp->b_un.b_addr;
		     dlp <= (struct disklabel *)(bp->b_un.b_addr+DEV_BSIZE-sizeof(*dlp));
		     dlp = (struct disklabel *)((char *)dlp + sizeof(long))) {
			if (dlp->d_magic != DISKMAGIC || dlp->d_magic2 != DISKMAGIC) {
				if (msg == NULL)
					msg = "no disk label";
			} else if (dlp->d_npartitions > MAXPARTITIONS ||
				   dkcksum(dlp) != 0)
				msg = "disk label corrupted";
			else {
				*lp = *dlp;
				msg = NULL;
				break;
			}
		}
	}
	bp->b_flags = B_INVAL | B_AGE;
	brelse(bp);
	return (msg);
}

#ifdef notyet

/*
 * Checksum routine for OMRON native disklabel
 */

#define	OMRON_LBLSIZE	512

u_short
omcksum(omp)
	register char *omp;
{
	register u_short *start, *end;
	register u_short sum = 0;

	start = (u_short *) omp;
	end = (u_short *) &start[(OMRON_LBLSIZE/sizeof(u_short) - 1)];
	while (start < end)
		sum ^= *start++;

	printf("omcksum: saved  ... 0x%s\n", hexstr(*end, 4));
	printf("omcksum: calced ... 0x%s\n", hexstr(sum, 4));

	return (sum);
}

/*
 * Write disk label back to device after modification.
 */
sdwritelabel(dev, strat, lp)
	dev_t dev;
	int (*strat)();
	register struct disklabel *lp;
{
	struct buf *bp;
	struct disklabel *dlp;
	int labelpart;
	int error = 0;

	labelpart = sdpart(dev);
	if (lp->d_partitions[labelpart].p_offset != 0) {
		if (lp->d_partitions[0].p_offset != 0)
			return (EXDEV);			/* not quite right */
		labelpart = 0;
	}

	bp = geteblk((int)lp->d_secsize);
	bp->b_dev = makedev(major(dev), sdminor(sdunit(dev), labelpart));
	bp->b_blkno = LABELSECTOR;
	bp->b_bcount = lp->d_secsize;
	bp->b_flags = B_READ;
	(*strat)(bp);
	if (error = biowait(bp))
		goto done;

	for (dlp = (struct disklabel *)bp->b_un.b_addr;
	    dlp <= (struct disklabel *)
	      (bp->b_un.b_addr + lp->d_secsize - sizeof(*dlp));
	    dlp = (struct disklabel *)((char *)dlp + sizeof(long))) {
		if (dlp->d_magic == DISKMAGIC && dlp->d_magic2 == DISKMAGIC &&
		    dkcksum(dlp) == 0) {
			omcksum(bp->b_un.b_addr);
/*
			*dlp = *lp;
			bp->b_flags = B_WRITE;
			(*strat)(bp);
			error = biowait(bp);
			goto done;
 */
		}
	}
	error = ESRCH;
done:
	brelse(bp);
	return (error);
}
#endif

#endif