From bf5a5d018c79bb458493aa7732f4aa8f5f221396 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Wed, 5 Apr 1995 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1995-04-05

---
 pc/scsi.c      | 61 +++++++++++++++++++++++------------------
 port/devsd.c   | 74 ++++++++++++++++++++++++++++++--------------------
 port/portfns.h |  2 +-
 3 files changed, 80 insertions(+), 57 deletions(-)

diff --git a/pc/scsi.c b/pc/scsi.c
index bd927c3296d17bfe50c0d2b5720ecf5ff9ec5bbd..c9eb371c906f82eb04b918801fa4afd08e86b09c 100644
--- a/pc/scsi.c
+++ b/pc/scsi.c
@@ -136,7 +136,9 @@ scsiprobe(Ctlr *ctlr)
 		 * Determine if the drive exists and is not ready or
 		 * is simply not responding
 		 */
-		if((s = scsireqsense(t, 0, 0)) != STok){
+		nbytes = Nscratch;
+		s = scsireqsense(t, 0, t->scratch, &nbytes, 0);
+		if(s != STok){
 			print("scsi%d: unit %d unavailable, status %d\n", t->ctlrno, i, s);
 			continue;
 		}
@@ -152,7 +154,7 @@ scsiprobe(Ctlr *ctlr)
 			print("scsi%d: unit %d inquire failed, status %d\n", t->ctlrno, i, s);
 			continue;
 		}
-		print("scsi%d: unit %d:%2.2ux: %s\n", t->ctlrno, i, t->inq[0], t->inq+8);
+		print("scsi%d: unit %d: %s\n", t->ctlrno, i, t->inq+8);
 		t->ok = 1;
 	}
 }
@@ -260,15 +262,12 @@ scsicap(Target *t, char lun, ulong *size, ulong *bsize)
 		return -1;
 
 	nbytes = 8;
-	s = scsiexec(t, SCSIread, cmd, sizeof(cmd), d, &nbytes);
-	if(s < 0) {
-		free(d);
-		return s;
+	if((s = scsiexec(t, SCSIread, cmd, sizeof(cmd), d, &nbytes)) == STok){
+		*size  = (d[0]<<24)|(d[1]<<16)|(d[2]<<8)|(d[3]<<0);
+		*bsize = (d[4]<<24)|(d[5]<<16)|(d[6]<<8)|(d[7]<<0);
 	}
-	*size  = (d[0]<<24)|(d[1]<<16)|(d[2]<<8)|(d[3]<<0);
-	*bsize = (d[4]<<24)|(d[5]<<16)|(d[6]<<8)|(d[7]<<0);
 	free(d);
-	return 0;
+	return s;
 }
 
 int
@@ -304,7 +303,8 @@ scsibio(Target *t, char lun, int dir, void *b, long n, long bsize, long bno)
 	nbytes = n*bsize;
 	s = scsiexec(t, dir, cmd, cdbsiz, b, &nbytes);
 	if(s < 0) {
-		scsireqsense(t, lun, 0);
+		nbytes = Nscratch;
+		scsireqsense(t, lun, t->scratch, &nbytes, 0);
 		return -1;
 	}
 	return nbytes;
@@ -331,37 +331,44 @@ static char *key[] =
 };
 
 int
-scsireqsense(Target *t, char lun, int quiet)
+scsireqsense(Target *t, char lun, void *data, int *nbytes, int quiet)
 {
 	char *s;
-	int sr, try, nbytes;
+	int status, try;
 	uchar cmd[6], *sense;
 
-	sense = t->scratch;
+	sense = malloc(*nbytes);
 
 	for(try = 0; try < 5; try++) {
 		memset(cmd, 0, sizeof(cmd));
 		cmd[0] = CMDreqsense;
 		cmd[1] = lun<<5;
-		cmd[4] = Nscratch;
-		memset(sense, 0, sizeof(sense));
+		cmd[4] = *nbytes;
+		memset(sense, 0, *nbytes);
 
-		nbytes = Nscratch;
-		sr = scsiexec(t, SCSIread, cmd, sizeof(cmd), sense, &nbytes);
-		if(sr != STok)
-			return sr;
+		status = scsiexec(t, SCSIread, cmd, sizeof(cmd), sense, nbytes);
+		if(status != STok){
+			free(sense);
+			return status;
+		}
+		*nbytes = sense[0x07]+8;
+		memmove(data, sense, *nbytes);
 
 		/*
 		 * Unit attention. We can handle that.
 		 */
-		if((sense[2] & 0x0F) == 0x00 || (sense[2] & 0x0F) == 0x06)
+		if((sense[2] & 0x0F) == 0x00 || (sense[2] & 0x0F) == 0x06){
+			free(sense);
 			return STok;
+		}
 
 		/*
 		 * Recovered error. Why bother telling me.
 		 */
-		if((sense[2] & 0x0F) == 0x01)
+		if((sense[2] & 0x0F) == 0x01){
+			free(sense);
 			return STok;
+		}
 
 		/*
 		 * Unit is becoming ready
@@ -372,12 +379,12 @@ scsireqsense(Target *t, char lun, int quiet)
 		delay(5000);
 	}
 
-	if(quiet)
-		return STcheck;
-
-	s = key[sense[2]&0xf];
-	print("scsi%d: unit %d reqsense: '%s' code #%2.2ux #%2.2ux\n",
-		t->ctlrno, t->target, s, sense[12], sense[13]);
+	if(quiet == 0){
+		s = key[sense[2]&0x0F];
+		print("scsi%d: unit %d reqsense: '%s' code #%2.2ux #%2.2ux\n",
+			t->ctlrno, t->target, s, sense[12], sense[13]);
+	}
+	free(sense);
 	return STcheck;
 }
 
diff --git a/port/devsd.c b/port/devsd.c
index 4e97c59fb0332a7e4c481293876843f8f9ad4e9b..07e5c6ac9b4baa9b620d21a9118ca76162c69f57 100644
--- a/port/devsd.c
+++ b/port/devsd.c
@@ -100,8 +100,7 @@ void
 sdinit(void)
 {
 	Disk *d;
-	ulong s, b;
-	uchar inq[255];
+	uchar scratch[0xFF], type;
 	int dev, i, nbytes;
 
 	dev = 0;
@@ -111,43 +110,48 @@ sdinit(void)
 		if(dev < 0)
 			break;
 
-		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 */
+		/*
+		 * Search for all the lun's.
+		 */
 		for(i = 0; i < Nlun; i++) {
 			d->lun = i;
-print("sd2|");
 
 			/*
 			 * A SCSI target does not support a lun if the
 			 * the peripheral device type and qualifier fields
 			 * in the response to an inquiry command are 0x7F.
 			 */
-			memset(inq, 0, sizeof(inq));
-			nbytes = sizeof(inq);
-			if(scsiinquiry(d->t, d->lun, inq, &nbytes) != STok || inq[0] == 0x7F)
+			nbytes = sizeof(scratch);
+			memset(scratch, 0, nbytes);
+			if(scsiinquiry(d->t, d->lun, scratch, &nbytes) != STok)
 				continue;
-print("sd3|");
-
-			s = 0;
-			b = 0;
-			if(scsicap(d->t, d->lun, &s, &b) != STok) {
-				scsireqsense(d->t, 0, 0);
+			if(scratch[0] == 0x7F)
 				continue;
-			}
-print("sd4/%d/%d|", s, b);
+			type = scratch[0] & 0x1F;
 
-			if(s == 0 || b == 0)
-				continue;
-print("sd5/0x%2.2ux|", d->inquire[0]);
+			/*
+			 * Read-capacity is mandatory for TypeDA, TypeMO and TypeCD.
+			 * It may return 'not ready' if TypeDA is not spun up,
+			 * TypeMO or TypeCD are not loaded or just plain slow getting
+			 * their act together after a reset.
+			 * If 'not ready' comes back, try starting a TypeDA and punt
+			 * the get capacity until the drive is attached.
+			 * It might be possible to be smarter here, and look at the
+			 * response from a test-unit-ready which would show if the
+			 * target was in the process of becoming ready.
+			 */
+			if(scsicap(d->t, d->lun, &d->size, &d->bsize) != STok) {
+				nbytes = sizeof(scratch);
+				memset(scratch, 0, nbytes);
+				scsireqsense(d->t, 0, scratch, &nbytes, 1);
+				if((scratch[2] & 0x0F) != 0x02)
+					continue;
+				if(type == TypeDA)
+					scsistart(d->t, d->lun, 0);
+				d->size = d->bsize = 0;
+			}
 
-			d->size = s;
-			d->bsize = b;
-			switch(d->inquire[0] & 0x1F){
+			switch(type){
 
 			case TypeDA:
 			case TypeMO:
@@ -161,7 +165,6 @@ print("sd5/0x%2.2ux|", d->inquire[0]);
 			default:
 				continue;
 			}
-print("sd6|");
 
 			if(++ndisk >= Ndisk)
 				break;
@@ -281,10 +284,23 @@ sdrdpart(Disk *d)
 	char *b, *line[Npart+2], *field[3];
 	static char MAGIC[] = "plan9 partitions";
 
+	/*
+	 * If the drive wasn't ready when we tried to do a
+	 * read-capacity earlier (in sdinit()), try again.
+	 * It might be possible to be smarter here, and look at the
+	 * response from a test-unit-ready which would show if the
+	 * target was in the process of becoming ready.
+	 */
+	if(d->size == 0 || d->bsize == 0){
+		if(scsicap(d->t, d->lun, &d->size, &d->bsize) != STok){
+			d->size = d->bsize = 0;
+			error(Eio);
+		}
+	}
+
 	b = scsialloc(d->bsize);
 	if(b == 0)
 		error(Enomem);
-
 	qlock(d);
 	
 	p = d->table;
diff --git a/port/portfns.h b/port/portfns.h
index c77d7bd32a6f85fe77d5c52e37759c8b84d8ebb7..b5c30c4845cc8c13e775259aa99fab88d5fbff56 100644
--- a/port/portfns.h
+++ b/port/portfns.h
@@ -241,7 +241,7 @@ int		scsiexec(Target*, int, uchar*, int, void*, int*);
 #define		scsifree(p)	free(p)
 int		scsiinquiry(Target*, char, void*, int*);
 int		scsiinv(int, int*, Target**, uchar**, char*);
-int		scsireqsense(Target*, char, int);
+int		scsireqsense(Target*, char, void*, int*, int);
 int		scsistart(Target*, char, int);
 int		scsitest(Target*, char);
 Target*		scsiunit(int, int);