From 701a12b4c5e8d25bf457a04090522ac15e84d8c7 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Thu, 29 Oct 1992 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1992-10-29

---
 gnot/scsibuf.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++
 port/devscsi.c | 43 +---------------------------------
 port/portfns.h |  1 +
 ss/main.c      |  2 +-
 ss/scsibuf.c   | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 129 insertions(+), 43 deletions(-)
 create mode 100644 gnot/scsibuf.c
 create mode 100644 ss/scsibuf.c

diff --git a/gnot/scsibuf.c b/gnot/scsibuf.c
new file mode 100644
index 0000000000000000000000000000000000000000..cc6edda894648d72ddf5c16fd676c195fb8e3991
--- /dev/null
+++ b/gnot/scsibuf.c
@@ -0,0 +1,63 @@
+#include "u.h"
+#include "../port/lib.h"
+#include "mem.h"
+#include "dat.h"
+#include "fns.h"
+#include "../port/error.h"
+#include "io.h"
+
+/*
+ * The following routines
+ *	scsibufreset, scsibuf, scsifree and scsialloc
+ * provide a pool of buffers used for scsi i/o.
+ * This is simplistic at best, and opportunities for
+ * deadlock abound.
+ */
+#define Nbuf	2
+
+struct {
+	Lock;
+	Scsibuf	*free;
+} scsibufalloc;
+
+void
+scsibufreset(ulong datasize)
+{
+	int i;
+
+	for(i = 0; i < Nbuf; i++)
+		scsifree(scsialloc(datasize));
+	lock(&scsibufalloc);
+	unlock(&scsibufalloc);
+}
+
+/*
+ * get a scsi io buffer of DATASIZE size
+ */
+Scsibuf *
+scsibuf(void)
+{
+	Scsibuf *b;
+
+	for(;;) {
+		lock(&scsibufalloc);
+		b = scsibufalloc.free;
+		if(b != 0) {
+			scsibufalloc.free = b->next;
+			unlock(&scsibufalloc);
+			return b;
+		}
+		unlock(&scsibufalloc);
+		resrcwait(0);
+	}
+	return 0;		/* not reached */
+}
+
+void
+scsifree(Scsibuf *b)
+{
+	lock(&scsibufalloc);
+	b->next = scsibufalloc.free;
+	scsibufalloc.free = b;
+	unlock(&scsibufalloc);
+}
diff --git a/port/devscsi.c b/port/devscsi.c
index 989b21fea18f71b79934991eb16bab8e18286cff..baba654e235429a513eab1691f6d182cca18f9f4 100644
--- a/port/devscsi.c
+++ b/port/devscsi.c
@@ -8,15 +8,10 @@
 
 #define	DPRINT	if(debug)kprint
 
-#define Nbuf	2
 #define DATASIZE	(32*512)
 #undef DATASIZE
 #define	DATASIZE	(64*1024)
 
-struct{
-	Lock;
-	Scsibuf	*free;
-}scsibufalloc;
 
 static Scsi	staticcmd;	/* BUG: should be one per scsi device */
 
@@ -83,12 +78,7 @@ scsigen(Chan *c, Dirtab *tab, long ntab, long s, Dir *dp)
 void
 scsireset(void)
 {
-	int i;
-
-	for(i = 0; i < Nbuf; i++)
-		scsifree(scsialloc(DATASIZE));
-	lock(&scsibufalloc);
-	unlock(&scsibufalloc);
+	scsibufreset(DATASIZE);
 	resetscsi();
 }
 
@@ -543,34 +533,3 @@ scsibwrite(int dev, Scsibuf *b, long n, long blocksize, long blockno)
 	qunlock(cmd);
 	return n;
 }
-
-/*
- * get a scsi io buffer of DATASIZE size
- */
-Scsibuf *
-scsibuf(void)
-{
-	Scsibuf *b;
-
-	for(;;) {
-		lock(&scsibufalloc);
-		b = scsibufalloc.free;
-		if(b != 0) {
-			scsibufalloc.free = b->next;
-			unlock(&scsibufalloc);
-			return b;
-		}
-		unlock(&scsibufalloc);
-		resrcwait(0);
-	}
-	return 0;		/* not reached */
-}
-
-void
-scsifree(Scsibuf *b)
-{
-	lock(&scsibufalloc);
-	b->next = scsibufalloc.free;
-	scsibufalloc.free = b;
-	unlock(&scsibufalloc);
-}
diff --git a/port/portfns.h b/port/portfns.h
index 49410090568cae686272990bb8342d014071a355..d84e37638df2f080567ce56e45a662137220964c 100644
--- a/port/portfns.h
+++ b/port/portfns.h
@@ -203,6 +203,7 @@ int		screenbits(void);
 Scsibuf*	scsialloc(ulong);
 int		scsibread(int, Scsibuf*, long, long, long);
 Scsibuf*	scsibuf(void);
+void		scsibufreset(ulong);
 int		scsibwrite(int, Scsibuf*, long, long, long);
 int		scsicap(int, void*);
 Scsi*		scsicmd(int, int, Scsibuf*, long);
diff --git a/ss/main.c b/ss/main.c
index 6bcf0bd3d5d1f05906fb20768d05786bbbd50cd7..053a221ac5c96fcc95c0dd8e17e2a10c218bae75 100644
--- a/ss/main.c
+++ b/ss/main.c
@@ -420,7 +420,7 @@ confinit(void)
 			v = mempres[i];
 			for(j=i+1; j<sparam->memscan && mempres[j]>v; j++)
 				v = mempres[j];
-			npg = ((v+1)-mempres[i])*MB/BY2PG;
+			npg = (j-i)*MB/BY2PG;
 			if(conf.npage0 == 0){
 				conf.base0 = i*MB;
 				conf.npage0 = npg;
diff --git a/ss/scsibuf.c b/ss/scsibuf.c
new file mode 100644
index 0000000000000000000000000000000000000000..cc6edda894648d72ddf5c16fd676c195fb8e3991
--- /dev/null
+++ b/ss/scsibuf.c
@@ -0,0 +1,63 @@
+#include "u.h"
+#include "../port/lib.h"
+#include "mem.h"
+#include "dat.h"
+#include "fns.h"
+#include "../port/error.h"
+#include "io.h"
+
+/*
+ * The following routines
+ *	scsibufreset, scsibuf, scsifree and scsialloc
+ * provide a pool of buffers used for scsi i/o.
+ * This is simplistic at best, and opportunities for
+ * deadlock abound.
+ */
+#define Nbuf	2
+
+struct {
+	Lock;
+	Scsibuf	*free;
+} scsibufalloc;
+
+void
+scsibufreset(ulong datasize)
+{
+	int i;
+
+	for(i = 0; i < Nbuf; i++)
+		scsifree(scsialloc(datasize));
+	lock(&scsibufalloc);
+	unlock(&scsibufalloc);
+}
+
+/*
+ * get a scsi io buffer of DATASIZE size
+ */
+Scsibuf *
+scsibuf(void)
+{
+	Scsibuf *b;
+
+	for(;;) {
+		lock(&scsibufalloc);
+		b = scsibufalloc.free;
+		if(b != 0) {
+			scsibufalloc.free = b->next;
+			unlock(&scsibufalloc);
+			return b;
+		}
+		unlock(&scsibufalloc);
+		resrcwait(0);
+	}
+	return 0;		/* not reached */
+}
+
+void
+scsifree(Scsibuf *b)
+{
+	lock(&scsibufalloc);
+	b->next = scsibufalloc.free;
+	scsibufalloc.free = b;
+	unlock(&scsibufalloc);
+}