tmscp.c

早期freebsd实现

		 * No more requests for this drive, remove
		 * from controller queue and look at next drive.
		 * We know we're at the head of the controller queue.
		 */
		dp->b_active = 0;
		um->um_tab.b_actf = dp->b_forw;
		continue;		/* Need to check for loop */
		}
	um->um_tab.b_active++;
	tmscpaddr = (struct tmscpdevice *)um->um_addr;
	ui = tmsdinfo[(TMSUNIT(bp->b_dev))];
	tms = &tms_info[ui->ui_unit];
	if ((tmscpaddr->tmscpsa&TMSCP_ERR) || sc->sc_state != S_RUN)
		{
		tprintf(tms->tms_tpr,
		    "tms%d: hard error bn%d\n",
		    minor(bp->b_dev)&03, bp->b_blkno);
		log(TMS_PRI, "tmscp%d: sa 0%o, state %d\n",um->um_ctlr,
				tmscpaddr->tmscpsa&0xffff, sc->sc_state);
		(void)tmscpinit(um->um_ctlr);
		/* SHOULD REQUEUE OUTSTANDING REQUESTS, LIKE TMSCPRESET */
		break;
		}
	/*
	 * Default is that last command was NOT a write command;
	 * if a write command is done it will be detected in tmscprsp.
	 */
	tms->tms_lastiow = 0;
	if (ui->ui_flags == 0)
		{        /* not online */
		if ((mp = tmscpgetcp(um)) == NULL)
			break;
		mp->mscp_opcode = M_OP_ONLIN;
		mp->mscp_unit = ui->ui_slave;
		dp->b_active = 2;
		um->um_tab.b_actf = dp->b_forw; /* remove from controller q */
		*((long *)mp->mscp_dscptr) |= TMSCP_OWN|TMSCP_INT;
		if (tmscpaddr->tmscpsa&TMSCP_ERR)
			printf("tmscp%d fatal error (0%o)\n",um->um_ctlr,
					tmscpaddr->tmscpsa&0xffff);
		i = tmscpaddr->tmscpip;
		continue;
		}
	switch (cpu) {

	case VAX_8600:
	case VAX_780:
		i = UBA_NEEDBDP|UBA_CANTWAIT;
		break;
	case VAX_750:
		i = um->um_ubinfo|UBA_HAVEBDP|UBA_CANTWAIT;
		break;
	case VAX_730:
	case VAX_630:
		i = UBA_CANTWAIT;
		break;
	}   /* end switch (cpu) */
	/*
	 * If command is an ioctl command then set the ioctl flag for later use.
	 * If not (i.e. it is a read or write) then attempt
	 * to set up a buffer pointer.
	 */
	ioctl = 0;
	if (bp == &ctmscpbuf[um->um_ctlr])
		ioctl = 1;
	else
		if ((i = ubasetup(um->um_ubanum, bp, i)) == 0)
			{
			if(dp->b_qsize != 0)
				break; /* When a command completes and */
				     /* frees a bdp tmscpstart will be called */
			if ((mp = tmscpgetcp(um)) == NULL)
				break;
#			ifdef DEBUG
			printd("tmscpstart: GTUNT %d ubasetup = %d\n",ui->ui_unit, i);
			if(tmscpdebug)DELAY(10000);
#			endif
			mp->mscp_opcode = M_OP_GTUNT;
			mp->mscp_unit = ui->ui_slave;
			*((long *)mp->mscp_dscptr) |= TMSCP_OWN|TMSCP_INT;
			if (tmscpaddr->tmscpsa&TMSCP_ERR)
				printf("tmscp%d: fatal error (0%o)\n",um->um_ctlr,
					    tmscpaddr->tmscpsa&0xffff);
			i = tmscpaddr->tmscpip;	/* initiate polling */
			break;
			}
#	if defined(VAX750)
	if (cpu == VAX_750)
		tempi = i & 0xfffffff;			/* mask off bdp */
	else
#	endif
		tempi = i;
	if ((mp = tmscpgetcp(um)) == NULL)
		{
		if (!ioctl)		/* only need to release if NOT ioctl */
			ubarelse(um->um_ubanum,&tempi);
		break;
		}
	mp->mscp_cmdref = (long)bp;		/* pointer to get back */
	mp->mscp_unit = ui->ui_slave;
	/*
	 * If its an ioctl-type command then set up the appropriate
	 * tmscp command;  by doing a switch on the "b_resid" field where
	 * the command mneumonic is stored.
	 */
	if (ioctl)
		{
#		ifdef DEBUG
		printd("tmscpstart: doing ioctl cmd %d\n", bp->b_resid);
#		endif
		/*
		 * The reccnt and tmkcnt fields are set to zero by the getcp
		 * routine (as bytecnt and buffer fields).  Thus reccnt and
		 * tmkcnt are only modified here if they need to be set to
		 * a non-zero value.
		 */
		switch ((int)bp->b_resid) {

		case TMS_WRITM:
			mp->mscp_opcode = M_OP_WRITM;
			break;
		case TMS_FSF:
			mp->mscp_opcode = M_OP_REPOS;
			mp->mscp_tmkcnt = bp->b_bcount;
			break;
		case TMS_BSF:
			mp->mscp_opcode = M_OP_REPOS;
			mp->mscp_modifier = M_MD_REVRS;
			mp->mscp_tmkcnt = bp->b_bcount;
			break;
		case TMS_FSR:
			mp->mscp_opcode = M_OP_REPOS;
			mp->mscp_modifier = M_MD_OBJCT;
			mp->mscp_reccnt = bp->b_bcount;
			break;
		case TMS_BSR:
			mp->mscp_opcode = M_OP_REPOS;
			mp->mscp_modifier = M_MD_REVRS | M_MD_OBJCT;
			mp->mscp_reccnt = bp->b_bcount;
			break;
		/*
		 * Clear serious exception is done for Rewind & Available cmds
		 */
		case TMS_REW:
			mp->mscp_opcode = M_OP_REPOS;
			mp->mscp_modifier = M_MD_REWND | M_MD_CLSEX;
			if (bp->b_bcount == 0)
				mp->mscp_modifier |= M_MD_IMMED;
			tms->tms_serex = 0;
			break;
		case TMS_OFFL:
			mp->mscp_opcode = M_OP_AVAIL;
			mp->mscp_modifier = M_MD_UNLOD | M_MD_CLSEX;
			tms->tms_serex = 0;
			break;
		case TMS_SENSE:
			mp->mscp_opcode = M_OP_GTUNT;
			break;
		case TMS_CACHE:
			mp->mscp_opcode = M_OP_STUNT;
			tms->tms_unitflgs |= M_UF_WBKNV;
			mp->mscp_unitflgs = tms->tms_unitflgs;
			mp->mscp_format = tms->tms_format;
			/* default device dependant parameters */
			mp->mscp_mediaid = 0;
			break;
		case TMS_NOCACHE:
			mp->mscp_opcode = M_OP_STUNT;
			tms->tms_unitflgs &= ~(M_UF_WBKNV);
			mp->mscp_unitflgs = tms->tms_unitflgs;
			mp->mscp_format = tms->tms_format;
			/* default device dependant parameters */
			mp->mscp_mediaid = 0;
			break;
		case TMS_CSE:
			/*
			 * This is a no-op command. It performs a 
			 * clear serious exception only.  (Done on a
			 * non-rewinding close after a serious exception.)
			 */
			mp->mscp_opcode = M_OP_REPOS;
			mp->mscp_modifier = M_MD_CLSEX;
			tms->tms_serex = 0;
			tms->tms_clserex = 1;
			break;
		case TMS_LOWDENSITY:
			/*
			 * Set the unit to low density
			 */
			mp->mscp_opcode = M_OP_STUNT;
			mp->mscp_unitflgs = tms->tms_unitflgs;
			mp->mscp_mediaid = 0;	/* default device dependant parameters */
			if ((tms->tms_fmtmenu & M_TF_800) != 0)
				mp->mscp_format = M_TF_800;
			else
				mp->mscp_format = M_TF_PE & tms->tms_fmtmenu;
			tms->tms_format = mp->mscp_format;
			break;
		case TMS_HIDENSITY:
			/*
			 * Set the unit to high density (format == 0)
			 */
			mp->mscp_opcode = M_OP_STUNT;
			mp->mscp_unitflgs = tms->tms_unitflgs;
			mp->mscp_mediaid = 0;	/* default device dependant parameters */
			mp->mscp_format = 0;
			tms->tms_format = 0;
			break;
		default:
			printf("Bad ioctl on tms unit %d\n", ui->ui_unit);
			/* Need a no-op. Reposition no amount */
			mp->mscp_opcode = M_OP_REPOS;
			break;
		}   /* end switch (bp->b_resid) */
		}
	else    /* Its a read/write command (not an ioctl) */
		{
		mp->mscp_opcode = bp->b_flags&B_READ ? M_OP_READ : M_OP_WRITE;
		mp->mscp_bytecnt = bp->b_bcount;
		mp->mscp_buffer = UBAI_ADDR(i) | (UBAI_BDP(i) << 24);

		bp->b_ubinfo = tempi;			/* save mapping info */
		}
	if (tms->tms_serex == 2)			/* if tape mark read */
		{
		mp->mscp_modifier |= M_MD_CLSEX;	/*  clear serious exc */
		tms->tms_serex = 0;
		}
	*((long *)mp->mscp_dscptr) |= TMSCP_OWN|TMSCP_INT;
#	ifdef DEBUG
	printd("tmscpstart: opcode 0%o mod %o unit %d cnt %d\n",mp->mscp_opcode,mp->mscp_modifier,mp->mscp_unit,mp->mscp_bytecnt);
	if(tmscpdebug)DELAY(100000);
#	endif
	i = tmscpaddr->tmscpip;              /* initiate polling */
	dp->b_qsize++;
	/*
	 * Move drive to the end of the controller queue
	 */
	if (dp->b_forw != NULL)
		{
		um->um_tab.b_actf = dp->b_forw;
		um->um_tab.b_actl->b_forw = dp;
		um->um_tab.b_actl = dp;
		dp->b_forw = NULL;
		}
	/*
	 * Move buffer to I/O wait queue
	 */
	dp->b_actf = bp->av_forw;
	dp = &tmscpwtab[um->um_ctlr];
	bp->av_forw = dp;
	bp->av_back = dp->av_back;
	dp->av_back->av_forw = bp;
	dp->av_back = bp;
	if (tmscpaddr->tmscpsa&TMSCP_ERR)
		{
		printf("tmscp%d: fatal error (0%o)\n", um->um_ctlr, tmscpaddr->tmscpsa&0xffff);
		(void)tmscpinit(um->um_ctlr);
		break;
		}
    }   /* end for */
    /*
     * Check for response ring transitions lost in the
     * Race condition
     */
    for (i = sc->sc_lastrsp;; i++)
	    {
	    i %= NRSP;
	    if (tm->tmscp_ca.ca_rspdsc[i]&TMSCP_OWN)
		    break;
	    tmscprsp(um, tm, sc, i);
	    tm->tmscp_ca.ca_rspdsc[i] |= TMSCP_OWN;
	    }
    sc->sc_lastrsp = i;
}


/*
 * Process a response packet
 */
tmscprsp(um, tm, sc, i)
	register struct uba_ctlr *um;
	register struct tmscp *tm;
	register struct tmscp_softc *sc;
	int i;
{
	register struct mscp *mp;
	register struct tms_info *tms;
	struct uba_device *ui;
	struct buf *dp, *bp;
	int st;

	mp = &tm->tmscp_rsp[i];
	mp->mscp_header.tmscp_msglen = mscp_msglen;
	sc->sc_credits += mp->mscp_header.tmscp_credits & 0xf;  /* low 4 bits */
	if ((mp->mscp_header.tmscp_credits & 0xf0) > 0x10)	/* Check */
		return;
#	ifdef DEBUG
	printd("tmscprsp, opcode 0%o status 0%o\n",mp->mscp_opcode,mp->mscp_status&M_ST_MASK);
#	endif	
	/*
	 * If it's an error log message (datagram),
	 * pass it on for more extensive processing.
	 */
	if ((mp->mscp_header.tmscp_credits & 0xf0) == 0x10)
		{	/* check */
		tmserror(um, (struct mslg *)mp);
		return;
		}
	st = mp->mscp_status&M_ST_MASK;
	/*
	 * The controller interrupts as drive 0.
	 * This means that you must check for controller interrupts
	 * before you check to see if there is a drive 0.
	 */
	if((M_OP_STCON|M_OP_END) == mp->mscp_opcode)
		{
		if (st == M_ST_SUCC)
			{
#		  	ifdef DEBUG
			printd("ctlr has %d credits\n", mp->mscp_header.tmscp_credits & 0xf);
			printd("ctlr timeout = %d\n", mp->mscp_cnttmo);
#			endif
			sc->sc_state = S_RUN;
			}
		else
			sc->sc_state = S_IDLE;
		um->um_tab.b_active = 0;
		wakeup((caddr_t)um);
		return;
		}
	if (mp->mscp_unit >= NTMS)
		return;
	if ((ui = tmscpip[um->um_ctlr][mp->mscp_unit]) == 0)
		return;
	tms = &tms_info[ui->ui_unit];
	/*
	 * Save endcode, endflags, and status for mtioctl get unit status.
	 * NOTE: Don't do this on Clear serious exception (reposition no-op);
	 *    which is done on close since this would
	 *    overwrite the real status we want.
	 */
	if (tms->tms_clserex != 1)
		{
		tms->tms_endcode = mp->mscp_opcode;
		tms->tms_flags = mp->mscp_flags;
		tms->tms_status = st;
		}
	else tms->tms_clserex = 0;

	switch (mp->mscp_opcode) {
	case M_OP_ONLIN|M_OP_END:
		tms->tms_type = mp->mscp_mediaid;
		dp = &tmsutab[ui->ui_unit];
		if (st == M_ST_SUCC)
			{
			/*
			 * Link the drive onto the controller queue
			 */
			dp->b_forw = NULL;
			if (um->um_tab.b_actf == NULL)
				um->um_tab.b_actf = dp;
			else
				um->um_tab.b_actl->b_forw = dp;
			um->um_tab.b_actl = dp;
			ui->ui_flags = 1;       /* mark it online */
			tms->tms_dsize=(daddr_t)mp->mscp_maxwrt;
#			ifdef DEBUG
			printd("tmscprsp: unit %d online\n", mp->mscp_unit);
#			endif			
			/* 
			 * This define decodes the Media type identifier
			 */
#	        	define F_to_C(x,i)     ( ((x)->mscp_mediaid) >> (i*5+7) & 0x1f ? ( ( (((x)->mscp_mediaid) >>( i*5 + 7)) & 0x1f) + 'A' - 1): ' ')
#			ifdef DEBUG
			printd("tmscprsp: unit %d online %x %c%c %c%c%c%d\n"
				,mp->mscp_unit, mp->mscp_mediaid ,F_to_C(mp,4)
				,F_to_C(mp,3), F_to_C(mp,2)
				,F_to_C(mp,1), F_to_C(mp,0), mp->mscp_mediaid & 0x7f);
#			endif				
			dp->b_active = 1;
			}	/* end if st == M_ST_SUCC */
		else 
			{
			if (bp = dp->b_actf)
				tprintf(tms->tms_tpr,
				    "tms%d: hard error bn%d: OFFLINE\n",
				    minor(bp->b_dev)&03, bp->b_blkno);
			else
				tprintf(tms->tms_tpr,
				    "tms%d: hard error: OFFLINE\n",
				    ui->ui_unit);
			while (bp = dp->b_actf)
				{
				dp->b_actf = bp->av_forw;
				bp->b_flags |= B_ERROR;
				iodone(bp);
				}
			}
		if(mp->mscp_cmdref!=NULL)
			/* Seems to get lost sometimes in uda */
			wakeup((caddr_t)mp->mscp_cmdref);
		break;
	/*
	 * The AVAILABLE ATTENTION message occurs when the
	 * unit becomes available after loading,
	 * marking the unit offline (ui_flags = 0) will force an
	 * online command prior to using the unit.
	 */
	case M_OP_AVATN:
		ui->ui_flags = 0;
		tms->tms_type = mp->mscp_mediaid;
		break;
	case M_OP_END:
		/*
		 * An endcode without an opcode (0200) is an invalid command.
		 * The mscp specification states that this would be a protocol
		 * type error, such as illegal opcodes. The mscp spec. also
		 * states that parameter error type of invalid commands should
		 * return the normal end message for the command. This does not appear
		 * to be the case. An invalid logical block number returned an endcode
		 * of 0200 instead of the 0241 (read) that was expected.
		 */
			
		printf("tmscp%d: invalid cmd, endcode = %o, status=%o\n",
			um->um_ctlr, mp->mscp_opcode, st);
		bp = (struct buf *)mp->mscp_cmdref;
		/*
		 * Unlink buffer from I/O wait queue.
		 * And signal iodone, so the higher level command can exit!
		 *
		 */
		bp->av_back->av_forw = bp->av_forw;
		bp->av_forw->av_back = bp->av_back;
		dp = &tmsutab[ui->ui_unit];
		dp->b_qsize--;
		iodone(bp);
		break;
	case M_OP_WRITE|M_OP_END:
		/* mark the last io op as a write */
		tms->tms_lastiow = 1;
	case M_OP_READ|M_OP_END:
	case M_OP_WRITM|M_OP_END:
	case M_OP_REPOS|M_OP_END:
	case M_OP_STUNT|M_OP_END:
	/*
	 * The AVAILABLE message occurs when the mt ioctl "rewoffl" is
	 * issued.  For the ioctl, "rewoffl", a tmscp AVAILABLE command is
	 * done with the UNLOAD modifier.  This performs a rewind, followed
	 * by marking the unit offline.  So mark the unit offline
	 * software wise as well (ui_flags = 0 and 
	 * tms->tms_openf = 0).
	 */
	case M_OP_AVAIL|M_OP_END:
#		ifdef DEBUG
		printd("tmscprsp: position = %d\n", mp->mscp_lbn);
#		endif
		bp = (struct buf *)mp->mscp_cmdref;
		/*
		 * Only need to release buffer if the command was read or write.
		 * No ubasetup was done in "tmscpstart" if it was an ioctl cmd.
		 */
		if (mp->mscp_opcode == (M_OP_READ|M_OP_END) || 
		    mp->mscp_opcode == (M_OP_WRITE|M_OP_END))
			ubarelse(um->um_ubanum, (int *)&bp->b_ubinfo);
		/*
		 * Unlink buffer from I/O wait queue.
		 */
		bp->av_back->av_forw = bp->av_forw;
		bp->av_forw->av_back = bp->av_back;
#		if defined(VAX750)
		if (cpu == VAX_750) { 
		    if ((tmscpwtab[um->um_ctlr].av_forw == &tmscpwtab[um->um_ctlr]) &&
					(um->um_ubinfo != 0)) {
			ubarelse(um->um_ubanum, &um->um_ubinfo);
		    }
		    else {
			if (mp->mscp_opcode == (M_OP_READ|M_OP_END) ||
		    	    mp->mscp_opcode == (M_OP_WRITE|M_OP_END))
				UBAPURGE(uba_hd[um->um_ubanum].uh_uba,(um->um_ubinfo >>28) & 0x0f);
		    }
		}
#		endif
		dp = &tmsutab[ui->ui_unit];
		dp->b_qsize--;
		if (st == M_ST_OFFLN || st == M_ST_AVLBL)
			{
			ui->ui_flags = 0;       /* mark unit offline */
			tms->tms_openf = 0;
			tms->tms_type = mp->mscp_mediaid;
			/*
			 * Link the buffer onto the front of the drive queue
			 */
			if ((bp->av_forw = dp->b_actf) == 0)
				dp->b_actl = bp;
			dp->b_actf = bp;
			/*
			 * Link the drive onto the controller queue
			 */
			if (dp->b_active == 0)
				{
				dp->b_forw = NULL;
				if (um->um_tab.b_actf == NULL)
					um->um_tab.b_actf = dp;
				else
					um->um_tab.b_actl->b_forw = dp;
				um->um_tab.b_actl = dp;
				dp->b_active = 1;
				}
#			if defined(VAX750)
			if (cpu == VAX_750 && um->um_ubinfo == 0)
				um->um_ubinfo = uballoc(um->um_ubanum, (caddr_t)0, 0, UBA_NEEDBDP);
#			endif
			return;
			}
		if (st != M_ST_SUCC)
			{
			if (mp->mscp_flags & M_EF_SEREX)
				tms->tms_serex = 1;
			if (st != M_ST_TAPEM)
				{
				tprintf(tms->tms_tpr,
				    "tms%d: hard error bn%d\n",
				    minor(bp->b_dev)&03, bp->b_blkno);
				errinfo(st);		/* produces more info */
#				ifdef DEBUG
				printd("tmscprsp: error; status sub-code = 0%o, flags = 0%o\n",
					(mp->mscp_status & 177740)>>5, mp->mscp_flags);
#				endif
				bp->b_flags |= B_ERROR;
				}
			else
				/* Hit a tape mark - Set serex flag to
				 * a special value so we can clear the