From f588189a1429b77c9caec9119ebaf42789c32793 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Tue, 4 Apr 1995 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1995-04-04

---
 pc/scsi.c      | 20 +++++++++++++-------
 port/devsd.c   | 33 ++++++++++++++-------------------
 port/portfns.h |  1 +
 3 files changed, 28 insertions(+), 26 deletions(-)

diff --git a/pc/scsi.c b/pc/scsi.c
index be7fda0ccc88c2d26031e49f863db3be21370dee..bd927c3296d17bfe50c0d2b5720ecf5ff9ec5bbd 100644
--- a/pc/scsi.c
+++ b/pc/scsi.c
@@ -124,18 +124,12 @@ static void
 scsiprobe(Ctlr *ctlr)
 {
 	Target *t;
-	uchar cmd[6];
 	int i, s, nbytes;
 
 	for(i = 0; i < NTarget; i++) {
 		t = &ctlr->target[i];
 
-		/*
-		 * Test unit ready
-		 */
-		memset(cmd, 0, sizeof(cmd));
-		s = scsiexec(t, SCSIread, cmd, sizeof(cmd), 0, 0);
-		if(s < 0)
+		if(scsitest(t, 0) < 0)
 			continue;
 
 		/*
@@ -215,6 +209,18 @@ print("devno %d = %s\n", devno, id);
 	return -1;
 }
 
+
+int
+scsitest(Target *t, char lun)
+{
+	uchar cmd[6];
+
+	memset(cmd, 0, sizeof(cmd));
+	cmd[0] = CMDtest;
+	cmd[1] = lun<<5;
+	return scsiexec(t, SCSIread, cmd, sizeof(cmd), 0, 0);
+}
+
 int
 scsistart(Target *t, char lun, int s)
 {
diff --git a/port/devsd.c b/port/devsd.c
index b077b615b99e49e396cee818188a14354a2ea45d..4e97c59fb0332a7e4c481293876843f8f9ad4e9b 100644
--- a/port/devsd.c
+++ b/port/devsd.c
@@ -11,9 +11,11 @@
 
 enum {
 	TypeDA		= 0x00,		/* Direct Access */
+	TypeSA		= 0x01,		/* Sequential Access */
 	TypeWO		= 0x04,		/* Worm */
 	TypeCD		= 0x05,		/* CD-ROM */
 	TypeMO		= 0x07,		/* rewriteable Magneto-Optical */
+	TYpeMC		= 0x08,		/* Medium Changer */
 };
 
 enum
@@ -59,7 +61,7 @@ static	void	sdrdpart(Disk*);
 static	long	sdio(Chan*, int, char*, ulong, ulong);
 
 static int types[] = {
-	TypeDA, TypeWO, TypeCD, TypeMO,
+	TypeDA, TypeCD, TypeMO,
 	-1,
 };
 
@@ -109,14 +111,16 @@ sdinit(void)
 		if(dev < 0)
 			break;
 
-		if(scsistart(d->t, 0, 1) != STok)
-			continue;
+		if(scsitest(d->t, 0) < 0)
+			scsireqsense(d->t, 0, 0);
+		if(scsistart(d->t, 0, 1) < 0)
+			scsireqsense(d->t, 0, 0);
+print("sd1|");
 
 		/* Search for other lun's */
 		for(i = 0; i < Nlun; i++) {
 			d->lun = i;
-
-			scsireqsense(d->t, d->lun, 1);
+print("sd2|");
 
 			/*
 			 * A SCSI target does not support a lun if the
@@ -127,35 +131,25 @@ sdinit(void)
 			nbytes = sizeof(inq);
 			if(scsiinquiry(d->t, d->lun, inq, &nbytes) != STok || inq[0] == 0x7F)
 				continue;
-
-			/* NCR Raid only seems to answer second capacity
-			 * command if lun != 0
-			 */
-			if(scsicap(d->t, d->lun, &s, &b) != STok) {
-				scsireqsense(d->t, 0, 1);
-				continue;
-			}
-			scsireqsense(d->t, 0, 1);
+print("sd3|");
 
 			s = 0;
 			b = 0;
 			if(scsicap(d->t, d->lun, &s, &b) != STok) {
-				scsireqsense(d->t, 0, 1);
+				scsireqsense(d->t, 0, 0);
 				continue;
 			}
-
-			if(scsireqsense(d->t, d->lun, 1) != STok)
-				continue;
+print("sd4/%d/%d|", s, b);
 
 			if(s == 0 || b == 0)
 				continue;
+print("sd5/0x%2.2ux|", d->inquire[0]);
 
 			d->size = s;
 			d->bsize = b;
 			switch(d->inquire[0] & 0x1F){
 
 			case TypeDA:
-			case TypeWO:
 			case TypeMO:
 				sprint(d->vol, "sd%d", ndisk);
 				break;
@@ -167,6 +161,7 @@ sdinit(void)
 			default:
 				continue;
 			}
+print("sd6|");
 
 			if(++ndisk >= Ndisk)
 				break;
diff --git a/port/portfns.h b/port/portfns.h
index 47fb04dfa53f20afbc4a39e46eb0b7cfe9d36c64..c77d7bd32a6f85fe77d5c52e37759c8b84d8ebb7 100644
--- a/port/portfns.h
+++ b/port/portfns.h
@@ -243,6 +243,7 @@ int		scsiinquiry(Target*, char, void*, int*);
 int		scsiinv(int, int*, Target**, uchar**, char*);
 int		scsireqsense(Target*, char, int);
 int		scsistart(Target*, char, int);
+int		scsitest(Target*, char);
 Target*		scsiunit(int, int);
 long		seconds(void);
 ulong		segattach(Proc*, ulong, char *, ulong, ulong);