mscp.c

早期freebsd实现

		bp->av_forw->av_back = bp->av_back;
		if (ui->ui_dk >= 0 && md->md_utab[ui->ui_unit].b_forw == NULL)
			dk_busy &= ~(1 << ui->ui_dk);

		/*
		 * If the transfer has something to do with bad
		 * block forwarding, let the driver handle the
		 * rest.
		 */
		if ((bp->b_flags & B_BAD) != 0 && md->md_bb != NULL) {
			(*md->md_bb)(ui, mp, bp);
			goto out;
		}

		/*
		 * If the transfer failed, give the driver a crack
		 * at fixing things up.
		 */
		if (st != M_ST_SUCCESS) {
			switch ((*md->md_ioerr)(ui, mp, bp)) {

			case MSCP_DONE:		/* fixed */
				break;

			case MSCP_RESTARTED:	/* still working on it */
				goto out;

			case MSCP_FAILED:	/* no luck */
				diskerr(bp, drivename, "hard error",
				    LOG_PRINTF, -1, md->md_lab ?
				    &md->md_lab[ui->ui_unit] : md->md_lab);
				mscp_printevent(mp);
				bp->b_flags |= B_ERROR;
				bp->b_error = EIO;
				break;
			}
		}

		/*
		 * Set the residual count and mark the transfer as
		 * done.  If the I/O wait queue is now empty, release
		 * the shared BDP, if any.
		 */
		info = bp->b_info;	/* we are about to clobber it */
		bp->b_resid = bp->b_bcount - mp->mscp_seq.seq_bytecount;
		(*md->md_iodone)(mi, bp, info);
out:
		break;
		
	case M_OP_REPLACE | M_OP_END:
		/*
		 * A replace operation finished.  Just let the driver
		 * handle it (if it does replaces).
		 */
		if (md->md_replace == NULL)
			printf("%s%d: bogus REPLACE end\n",
				drivename, ui->ui_unit);
		else
			(*md->md_replace)(ui, mp);
		break;

	default:
		/*
		 * If it is not one of the above, we cannot handle it.
		 * (And we should not have received it, for that matter.)
		 */
unknown:
		printf("%s%d: unknown opcode 0x%x status 0x%x ignored\n",
			mi->mi_md->md_dname, ui->ui_unit,
			mp->mscp_opcode, mp->mscp_status);
		mscp_hexdump(mp);
		break;
	}

	/*
	 * If the drive needs to be put back in the controller queue,
	 * do that now.  (`bp' below ought to be `dp', but they are all
	 * struct buf *.)  Note that b_active was cleared in the driver;
	 * we presume that there is something to be done, hence reassert it.
	 */
	if (ui->ui_flags & UNIT_REQUEUE) {
		bp = &md->md_utab[ui->ui_unit];
if (bp->b_active) panic("mscp_dorsp requeue");
		APPEND(bp, mi->mi_tab, b_forw);
		bp->b_active = 1;
		ui->ui_flags &= ~UNIT_REQUEUE;
	}

done:
	/*
	 * Give back the response packet, and take a look at the next.
	 */
	mp->mscp_msglen = MSCP_MSGLEN;
	mi->mi_rsp.mri_desc[nextrsp] |= MSCP_OWN;
	nextrsp = (nextrsp + 1) % mi->mi_rsp.mri_size;
	goto loop;
}

/*
 * Dump the entire contents of an MSCP packet in hex.  Mainly useful
 * for debugging....
 */
mscp_hexdump(mp)
	register struct mscp *mp;
{
	register long *p = (long *) mp;
	register int i = mp->mscp_msglen;

	if (i > 256)		/* sanity */
		i = 256;
	i /= sizeof (*p);	/* ASSUMES MULTIPLE OF sizeof(long) */
	while (--i >= 0)
		printf("0x%x ", *p++);
	printf("\n");
}

/*
 * Requeue outstanding transfers, e.g., after bus reset.
 * Also requeue any drives that have on line or unit status
 * info pending.
 */
mscp_requeue(mi)
	struct mscp_info *mi;
{
	register struct uba_device *ui;
	register struct mscp_driver *md = mi->mi_md;
	register struct buf *bp, *dp;
	register int unit;
	struct buf *nextbp;

	/*
	 * Clear the controller chain.  Mark everything un-busy; we
	 * will soon fix any that are in fact busy.
	 */
	mi->mi_tab->b_actf = NULL;
	mi->mi_tab->b_active = 0;
	for (unit = 0, dp = md->md_utab; unit < md->md_nunits; unit++, dp++) {
		ui = md->md_dinfo[unit];
		if (ui == NULL || !ui->ui_alive || ui->ui_ctlr != mi->mi_ctlr)
			continue;	/* not ours */
		dp->b_forw = NULL;
		dp->b_active = 0;
	}

	/*
	 * Scan the wait queue, linking buffers onto drive queues.
	 * Note that these must be put at the front of the drive queue,
	 * lest we reorder I/O operations.
	 */
	for (bp = mi->mi_wtab.av_back; bp != &mi->mi_wtab; bp = nextbp) {
		nextbp = bp->av_back;
		dp = &md->md_utab[minor(bp->b_dev) >> md->md_unitshift];
		bp->av_forw = dp->b_actf;
		if (dp->b_actf == NULL)
			dp->b_actl = bp;
		dp->b_actf = bp;
	}
	mi->mi_wtab.av_forw = mi->mi_wtab.av_back = &mi->mi_wtab;

	/*
	 * Scan for drives waiting for on line or status responses,
	 * and for drives with pending transfers.  Put these on the
	 * controller queue, and mark the controller busy.
	 */
	for (unit = 0, dp = md->md_utab; unit < md->md_nunits; unit++, dp++) {
		ui = md->md_dinfo[unit];
		if (ui == NULL || !ui->ui_alive || ui->ui_ctlr != mi->mi_ctlr)
			continue;
		ui->ui_flags &= ~(UNIT_HAVESTATUS | UNIT_ONLINE);
		if ((ui->ui_flags & UNIT_REQUEUE) == 0 && dp->b_actf == NULL)
			continue;
		ui->ui_flags &= ~UNIT_REQUEUE;
		APPEND(dp, mi->mi_tab, b_forw);
		dp->b_active = 1;
		mi->mi_tab->b_active = 1;
	}

#ifdef AVOID_EMULEX_BUG
	/*
	 * ... and clear the index-to-buffer table.
	 */
	for (unit = 0; unit < AEB_MAX_BP; unit++)
		mi->mi_bp[unit] = 0;
#endif
}


/*
 * MSCP error reporting
 */

/*
 * Messages for the various subcodes.
 */
static char unknown_msg[] = "unknown subcode";

/*
 * Subcodes for Success (0)
 */
static char *succ_msgs[] = {
	"normal",		/* 0 */
	"spin down ignored",	/* 1 = Spin-Down Ignored */
	"still connected",	/* 2 = Still Connected */
	unknown_msg,
	"dup. unit #",		/* 4 = Duplicate Unit Number */
	unknown_msg,
	unknown_msg,
	unknown_msg,
	"already online",	/* 8 = Already Online */
	unknown_msg,
	unknown_msg,
	unknown_msg,
	unknown_msg,
	unknown_msg,
	unknown_msg,
	unknown_msg,
	"still online",		/* 16 = Still Online */
};

/*
 * Subcodes for Invalid Command (1)
 */
static char *icmd_msgs[] = {
	"invalid msg length",	/* 0 = Invalid Message Length */
};

/*
 * Subcodes for Command Aborted (2)
 */
/* none known */

/*
 * Subcodes for Unit Offline (3)
 */
static char *offl_msgs[] = {
	"unknown drive",	/* 0 = Unknown, or online to other ctlr */
	"not mounted",		/* 1 = Unmounted, or RUN/STOP at STOP */
	"inoperative",		/* 2 = Unit Inoperative */
	unknown_msg,
	"duplicate",		/* 4 = Duplicate Unit Number */
	unknown_msg,
	unknown_msg,
	unknown_msg,
	"in diagnosis",		/* 8 = Disabled by FS or diagnostic */
};

/*
 * Subcodes for Unit Available (4)
 */
/* none known */

/*
 * Subcodes for Media Format Error (5)
 */
static char *media_fmt_msgs[] = {
	"fct unread - edc",	/* 0 = FCT unreadable */
	"invalid sector header",/* 1 = Invalid Sector Header */
	"not 512 sectors",	/* 2 = Not 512 Byte Sectors */
	"not formatted",	/* 3 = Not Formatted */
	"fct ecc",		/* 4 = FCT ECC */
};

/*
 * Subcodes for Write Protected (6)
 * N.B.:  Code 6 subcodes are 7 bits higher than other subcodes
 * (i.e., bits 12-15).
 */
static char *wrprot_msgs[] = {
	unknown_msg,
	"software",		/* 1 = Software Write Protect */
	"hardware",		/* 2 = Hardware Write Protect */
};

/*
 * Subcodes for Compare Error (7)
 */
/* none known */

/*
 * Subcodes for Data Error (8)
 */
static char *data_msgs[] = {
	"forced error",		/* 0 = Forced Error (software) */
	unknown_msg,
	"header compare",	/* 2 = Header Compare Error */
	"sync timeout",		/* 3 = Sync Timeout Error */
	unknown_msg,
	unknown_msg,
	unknown_msg,
	"uncorrectable ecc",	/* 7 = Uncorrectable ECC */
	"1 symbol ecc",		/* 8 = 1 bit ECC */
	"2 symbol ecc",		/* 9 = 2 bit ECC */
	"3 symbol ecc",		/* 10 = 3 bit ECC */
	"4 symbol ecc",		/* 11 = 4 bit ECC */
	"5 symbol ecc",		/* 12 = 5 bit ECC */
	"6 symbol ecc",		/* 13 = 6 bit ECC */
	"7 symbol ecc",		/* 14 = 7 bit ECC */
	"8 symbol ecc",		/* 15 = 8 bit ECC */
};

/*
 * Subcodes for Host Buffer Access Error (9)
 */
static char *host_buffer_msgs[] = {
	unknown_msg,
	"odd xfer addr",	/* 1 = Odd Transfer Address */
	"odd xfer count",	/* 2 = Odd Transfer Count */
	"non-exist. memory",	/* 3 = Non-Existent Memory */
	"memory parity",	/* 4 = Memory Parity Error */
};

/*
 * Subcodes for Controller Error (10)
 */
static char *cntlr_msgs[] = {
	unknown_msg,
	"serdes overrun",	/* 1 = Serialiser/Deserialiser Overrun */
	"edc",			/* 2 = Error Detection Code? */
	"inconsistant internal data struct",/* 3 = Internal Error */
};

/*
 * Subcodes for Drive Error (11)
 */
static char *drive_msgs[] = {
	unknown_msg,
	"sdi command timeout",	/* 1 = SDI Command Timeout */
	"ctlr detected protocol",/* 2 = Controller Detected Protocol Error */
	"positioner",		/* 3 = Positioner Error */
	"lost rd/wr ready",	/* 4 = Lost R/W Ready Error */
	"drive clock dropout",	/* 5 = Lost Drive Clock */
	"lost recvr ready",	/* 6 = Lost Receiver Ready */
	"drive detected error",	/* 7 = Drive Error */
	"ctlr detected pulse or parity",/* 8 = Pulse or Parity Error */
};

/*
 * The following table correlates message codes with the
 * decoding strings.
 */
struct code_decode {
	char	*cdc_msg;
	int	cdc_nsubcodes;
	char	**cdc_submsgs;
} code_decode[] = {
#define	SC(m)	sizeof (m) / sizeof (m[0]), m
	"success",			SC(succ_msgs),
	"invalid command",		SC(icmd_msgs),
	"command aborted",		0, 0,
	"unit offline",		SC(offl_msgs),
	"unit available",		0, 0,
	"media format error",		SC(media_fmt_msgs),
	"write protected",		SC(wrprot_msgs),
	"compare error",		0, 0,
	"data error",			SC(data_msgs),
	"host buffer access error",	SC(host_buffer_msgs),
	"controller error",		SC(cntlr_msgs),
	"drive error",			SC(drive_msgs),
#undef SC
};

/*
 * Print the decoded error event from an MSCP error datagram.
 */
mscp_printevent(mp)
	struct mscp *mp;
{
	register int event = mp->mscp_event;
	register struct code_decode *cdc;
	int c, sc;
	char *cm, *scm;

	/*
	 * The code is the lower six bits of the event number (aka
	 * status).  If that is 6 (write protect), the subcode is in
	 * bits 12-15; otherwise, it is in bits 5-11.
	 * I WONDER WHAT THE OTHER BITS ARE FOR.  IT SURE WOULD BE
	 * NICE IF DEC SOLD DOCUMENTATION FOR THEIR OWN CONTROLLERS.
	 */
	c = event & M_ST_MASK;
	sc = (c != 6 ? event >> 5 : event >> 12) & 0x7ff;
	if (c >= sizeof code_decode / sizeof code_decode[0])
		cm = "- unknown code", scm = "??";
	else {
		cdc = &code_decode[c];
		cm = cdc->cdc_msg;
		if (sc >= cdc->cdc_nsubcodes)
			scm = unknown_msg;
		else
			scm = cdc->cdc_submsgs[sc];
	}
	printf(" %s (%s) (code %d, subcode %d)\n", cm, scm, c, sc);
}

/*
 * Print the code and logical block number for an error packet.
 * THIS IS PROBABLY PECULIAR TO DISK DRIVES.  IT SURE WOULD BE
 * NICE IF DEC SOLD DOCUMENTATION FOR THEIR OWN CONTROLLERS.
 */
mscp_decodeerror(name, ctlr, mp)
	char *name;
	int ctlr;
	register struct mscp *mp;
{
	/*
	 * For bad blocks, mp->mscp_erd.erd_hdr identifies a code and
	 * the logical block number.  Code 0 is a regular block; code 6
	 * is a replacement block.  The remaining codes are currently
	 * undefined.  The code is in the upper four bits of the header
	 * (bits 0-27 are the lbn).
	 */
	int issoft = mp->mscp_flags & (M_LF_SUCC | M_LF_CONT);
	static char *codemsg[16] = {
		"lbn", "code 1", "code 2", "code 3",
		"code 4", "code 5", "rbn", "code 7",
		"code 8", "code 9", "code 10", "code 11",
		"code 12", "code 13", "code 14", "code 15"
	};
#define BADCODE(h)	(codemsg[(unsigned)(h) >> 28])
#define BADLBN(h)	((h) & 0xfffffff)

	printf("%s%d: %s error datagram%s:", name, ctlr,
		issoft ? "soft" : "hard",
		mp->mscp_flags & M_LF_CONT ? " (continuing)" : "");
	switch (mp->mscp_format & 0377) {

	case M_FM_CTLRERR:	/* controller error */
		break;

	case M_FM_BUSADDR:	/* host memory access error */
		printf(" memory addr 0x%x:", mp->mscp_erd.erd_busaddr);
		break;

	case M_FM_DISKTRN:
		printf(" unit %d: level %d retry %d, %s %d:",
			mp->mscp_unit,
			mp->mscp_erd.erd_level, mp->mscp_erd.erd_retry,
			BADCODE(mp->mscp_erd.erd_hdr),
			BADLBN(mp->mscp_erd.erd_hdr));
		break;

	case M_FM_SDI:
		printf(" unit %d: %s %d:", mp->mscp_unit,
			BADCODE(mp->mscp_erd.erd_hdr),
			BADLBN(mp->mscp_erd.erd_hdr));
		break;

	case M_FM_SMLDSK:
		printf(" unit %d: small disk error, cyl %d:",
			mp->mscp_unit, mp->mscp_erd.erd_sdecyl);
		break;

	default:
		printf(" unit %d: unknown error, format 0x%x:",
			mp->mscp_unit, mp->mscp_format);
	}
	mscp_printevent(mp);
#undef BADCODE
#undef BADLBN
}