Changed swap partition handling/allocation so that it doesn't

require specific partitions be mentioned in the kernel config
file ("swap on foo" is now obsolete).

From Poul-Henning:

The visible effect is this:

As default, unless
        options "NSWAPDEV=23"
is in your config, you will have four swap-devices.
You can swapon(2) any block device you feel like, it doesn't have
to be in the kernel config.

There is a performance/resource win available by getting the NSWAPDEV right
(but only if you have just one swap-device ??), but using that as default
would be too restrictive.

The invisible effect is that:

Swap-handling disappears from the $arch part of the kernel.
It gets a lot simpler (-145 lines) and cleaner.

Reviewed by:	John Dyson, David Greenman
Submitted by:	Poul-Henning Kamp, with minor changes by me.

18 files changed, 118 insertions, 302 deletions

diff --git a/sys/amd64/amd64/autoconf.c b/sys/amd64/amd64/autoconf.c
index 8761799b591b..aae1850ca8d3 100644
--- a/sys/amd64/amd64/autoconf.c
+++ b/sys/amd64/amd64/autoconf.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)autoconf.c	7.1 (Berkeley) 5/9/91
- *	$Id: autoconf.c,v 1.29 1995/05/11 19:26:07 rgrimes Exp $
+ *	$Id: autoconf.c,v 1.30 1995/05/12 19:17:11 wollman Exp $
  */
 
 /*
@@ -57,7 +57,6 @@
 #include <machine/md_var.h>
 #include <machine/pte.h>
 
-static void swapconf(void);
 static void setroot(void);
 
 /*
@@ -209,43 +208,9 @@ configure()
 	 * parameter based on device(s) used.
 	 */
 	setconf();
-	swapconf();
 	cold = 0;
 }
 
-/*
- * Configure swap space and related parameters.
- */
-static void
-swapconf()
-{
-	register struct swdevt *swp;
-	register int nblks;
-
-	for (swp = swdevt; swp->sw_dev > 0; swp++)
-	{
-		unsigned d = major(swp->sw_dev);
-
-		if (d > nblkdev) break;
-		if (bdevsw[d].d_psize) {
-			nblks = (*bdevsw[d].d_psize)(swp->sw_dev);
-			if (nblks > 0 &&
-			    (swp->sw_nblks == 0 || swp->sw_nblks > nblks))
-				swp->sw_nblks = nblks;
-			else
-				swp->sw_nblks = 0;
-		}
-		swp->sw_nblks = ctod(dtoc(swp->sw_nblks));
-	}
-	if (dumpdev != NODEV) {
-		if (dumplo == 0 && bdevsw[major(dumpdev)].d_psize)
-			dumplo = (*bdevsw[major(dumpdev)].d_psize)(dumpdev) -
-				Maxmem*NBPG/512;
-		if (dumplo < 0)
-			dumplo = 0;
-	}
-}
-
 int
 setdumpdev(dev_t dev)
 {
@@ -267,7 +232,6 @@ setdumpdev(dev_t dev)
 	/*NOTREACHED*/
 }	
 
-#define	DOSWAP			/* change swdevt and dumpdev */
 u_long	bootdev = 0;		/* should be dev_t, but not until 32 bits */
 
 static	char devname[][2] = {
@@ -325,25 +289,4 @@ setroot()
 		devname[majdev][0], devname[majdev][1],
 		mindev >> (majdev == FDMAJOR ? FDUNITSHIFT : PARTITIONSHIFT),
 		part + 'a');
-#ifdef DOSWAP
-	mindev &= ~PARTITIONMASK;
-	for (swp = swdevt; swp->sw_dev; swp++) {
-		if (majdev == major(swp->sw_dev) &&
-		    mindev == (minor(swp->sw_dev) & ~PARTITIONMASK)) {
-
-			temp = swdevt[0].sw_dev;
-			swdevt[0].sw_dev = swp->sw_dev;
-			swp->sw_dev = temp;
-			break;
-		}
-	}
-	if (swp->sw_dev == 0)
-		return;
-	/*
-	 * If dumpdev was the same as the old primary swap
-	 * device, move it to the new primary swap device.
-	 */
-	if (temp == dumpdev)
-		dumpdev = swdevt[0].sw_dev;
-#endif
 }
diff --git a/sys/amd64/conf/GENERIC b/sys/amd64/conf/GENERIC
index 2514f7899325..675c405007f8 100644
--- a/sys/amd64/conf/GENERIC
+++ b/sys/amd64/conf/GENERIC
@@ -1,7 +1,7 @@
 #
 # GENERIC -- Generic machine with WD/AHx/NCR/BTx family disks
 #
-#	$Id: GENERIC,v 1.43 1995/04/24 05:33:58 phk Exp $
+#	$Id: GENERIC,v 1.44 1995/05/02 04:40:06 phk Exp $
 #
 
 machine		"i386"
@@ -23,7 +23,7 @@ options		"SCSI_DELAY=15"		#Be pessimistic about Joe SCSI device
 options		BOUNCE_BUFFERS		#include support for DMA bounce buffers
 options		UCONSOLE		#Allow users to grab the console
 
-config		kernel	root on wd0 swap on wd0 and wd1 and wd2 and wd3 and sd0 and sd1 and vn0 dumps on wd0
+config		kernel	root on wd0 
 
 controller	isa0
 controller	pci0
diff --git a/sys/conf/NOTES b/sys/conf/NOTES
index ce8a25056c04..15338e8c4688 100644
--- a/sys/conf/NOTES
+++ b/sys/conf/NOTES
@@ -2,7 +2,7 @@
 # LINT -- config file for checking all the sources, tries to pull in
 #	as much of the source tree as it can.
 #
-#	$Id: LINT,v 1.179 1995/05/11 02:15:37 jkh Exp $
+#	$Id: LINT,v 1.180 1995/05/12 15:17:55 ache Exp $
 #
 # NB: You probably don't want to try running a kernel built from this
 # file.  Instead, you should start from GENERIC, and add options from
@@ -58,7 +58,7 @@ options		MATH_EMULATE		#Support for x87 emulation
 #  - The kernel can swap on wd0b and sd0b, defaulting to the former
 #  - Crash dumps will be written to wd0b, if possible
 #
-config		kernel	root on wd0 swap on wd0 and sd0 dumps on wd0
+config		kernel	root on wd0 
 
 
 #####################################################################
@@ -251,7 +251,9 @@ options		UNION			#Union filesystem
 # of kilobytes to reserve for the filesystem.
 options		"MFS_ROOT=10"
 
-#
+# Allow this many swap-devices.
+options		"NSWAPDEV=20"
+
 # Disk quotas are supported when this option is enabled.  If you
 # change the value of this option, you must do a `make clean' in your
 # kernel compile directory in order to get a working kernel.
diff --git a/sys/i386/conf/GENERIC b/sys/i386/conf/GENERIC
index 2514f7899325..675c405007f8 100644
--- a/sys/i386/conf/GENERIC
+++ b/sys/i386/conf/GENERIC
@@ -1,7 +1,7 @@
 #
 # GENERIC -- Generic machine with WD/AHx/NCR/BTx family disks
 #
-#	$Id: GENERIC,v 1.43 1995/04/24 05:33:58 phk Exp $
+#	$Id: GENERIC,v 1.44 1995/05/02 04:40:06 phk Exp $
 #
 
 machine		"i386"
@@ -23,7 +23,7 @@ options		"SCSI_DELAY=15"		#Be pessimistic about Joe SCSI device
 options		BOUNCE_BUFFERS		#include support for DMA bounce buffers
 options		UCONSOLE		#Allow users to grab the console
 
-config		kernel	root on wd0 swap on wd0 and wd1 and wd2 and wd3 and sd0 and sd1 and vn0 dumps on wd0
+config		kernel	root on wd0 
 
 controller	isa0
 controller	pci0
diff --git a/sys/i386/conf/LINT b/sys/i386/conf/LINT
index ce8a25056c04..15338e8c4688 100644
--- a/sys/i386/conf/LINT
+++ b/sys/i386/conf/LINT
@@ -2,7 +2,7 @@
 # LINT -- config file for checking all the sources, tries to pull in
 #	as much of the source tree as it can.
 #
-#	$Id: LINT,v 1.179 1995/05/11 02:15:37 jkh Exp $
+#	$Id: LINT,v 1.180 1995/05/12 15:17:55 ache Exp $
 #
 # NB: You probably don't want to try running a kernel built from this
 # file.  Instead, you should start from GENERIC, and add options from
@@ -58,7 +58,7 @@ options		MATH_EMULATE		#Support for x87 emulation
 #  - The kernel can swap on wd0b and sd0b, defaulting to the former
 #  - Crash dumps will be written to wd0b, if possible
 #
-config		kernel	root on wd0 swap on wd0 and sd0 dumps on wd0
+config		kernel	root on wd0 
 
 
 #####################################################################
@@ -251,7 +251,9 @@ options		UNION			#Union filesystem
 # of kilobytes to reserve for the filesystem.
 options		"MFS_ROOT=10"
 
-#
+# Allow this many swap-devices.
+options		"NSWAPDEV=20"
+
 # Disk quotas are supported when this option is enabled.  If you
 # change the value of this option, you must do a `make clean' in your
 # kernel compile directory in order to get a working kernel.
diff --git a/sys/i386/conf/NOTES b/sys/i386/conf/NOTES
index ce8a25056c04..15338e8c4688 100644
--- a/sys/i386/conf/NOTES
+++ b/sys/i386/conf/NOTES
@@ -2,7 +2,7 @@
 # LINT -- config file for checking all the sources, tries to pull in
 #	as much of the source tree as it can.
 #
-#	$Id: LINT,v 1.179 1995/05/11 02:15:37 jkh Exp $
+#	$Id: LINT,v 1.180 1995/05/12 15:17:55 ache Exp $
 #
 # NB: You probably don't want to try running a kernel built from this
 # file.  Instead, you should start from GENERIC, and add options from
@@ -58,7 +58,7 @@ options		MATH_EMULATE		#Support for x87 emulation
 #  - The kernel can swap on wd0b and sd0b, defaulting to the former
 #  - Crash dumps will be written to wd0b, if possible
 #
-config		kernel	root on wd0 swap on wd0 and sd0 dumps on wd0
+config		kernel	root on wd0 
 
 
 #####################################################################
@@ -251,7 +251,9 @@ options		UNION			#Union filesystem
 # of kilobytes to reserve for the filesystem.
 options		"MFS_ROOT=10"
 
-#
+# Allow this many swap-devices.
+options		"NSWAPDEV=20"
+
 # Disk quotas are supported when this option is enabled.  If you
 # change the value of this option, you must do a `make clean' in your
 # kernel compile directory in order to get a working kernel.
diff --git a/sys/i386/i386/autoconf.c b/sys/i386/i386/autoconf.c
index 8761799b591b..aae1850ca8d3 100644
--- a/sys/i386/i386/autoconf.c
+++ b/sys/i386/i386/autoconf.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)autoconf.c	7.1 (Berkeley) 5/9/91
- *	$Id: autoconf.c,v 1.29 1995/05/11 19:26:07 rgrimes Exp $
+ *	$Id: autoconf.c,v 1.30 1995/05/12 19:17:11 wollman Exp $
  */
 
 /*
@@ -57,7 +57,6 @@
 #include <machine/md_var.h>
 #include <machine/pte.h>
 
-static void swapconf(void);
 static void setroot(void);
 
 /*
@@ -209,43 +208,9 @@ configure()
 	 * parameter based on device(s) used.
 	 */
 	setconf();
-	swapconf();
 	cold = 0;
 }
 
-/*
- * Configure swap space and related parameters.
- */
-static void
-swapconf()
-{
-	register struct swdevt *swp;
-	register int nblks;
-
-	for (swp = swdevt; swp->sw_dev > 0; swp++)
-	{
-		unsigned d = major(swp->sw_dev);
-
-		if (d > nblkdev) break;
-		if (bdevsw[d].d_psize) {
-			nblks = (*bdevsw[d].d_psize)(swp->sw_dev);
-			if (nblks > 0 &&
-			    (swp->sw_nblks == 0 || swp->sw_nblks > nblks))
-				swp->sw_nblks = nblks;
-			else
-				swp->sw_nblks = 0;
-		}
-		swp->sw_nblks = ctod(dtoc(swp->sw_nblks));
-	}
-	if (dumpdev != NODEV) {
-		if (dumplo == 0 && bdevsw[major(dumpdev)].d_psize)
-			dumplo = (*bdevsw[major(dumpdev)].d_psize)(dumpdev) -
-				Maxmem*NBPG/512;
-		if (dumplo < 0)
-			dumplo = 0;
-	}
-}
-
 int
 setdumpdev(dev_t dev)
 {
@@ -267,7 +232,6 @@ setdumpdev(dev_t dev)
 	/*NOTREACHED*/
 }	
 
-#define	DOSWAP			/* change swdevt and dumpdev */
 u_long	bootdev = 0;		/* should be dev_t, but not until 32 bits */
 
 static	char devname[][2] = {
@@ -325,25 +289,4 @@ setroot()
 		devname[majdev][0], devname[majdev][1],
 		mindev >> (majdev == FDMAJOR ? FDUNITSHIFT : PARTITIONSHIFT),
 		part + 'a');
-#ifdef DOSWAP
-	mindev &= ~PARTITIONMASK;
-	for (swp = swdevt; swp->sw_dev; swp++) {
-		if (majdev == major(swp->sw_dev) &&
-		    mindev == (minor(swp->sw_dev) & ~PARTITIONMASK)) {
-
-			temp = swdevt[0].sw_dev;
-			swdevt[0].sw_dev = swp->sw_dev;
-			swp->sw_dev = temp;
-			break;
-		}
-	}
-	if (swp->sw_dev == 0)
-		return;
-	/*
-	 * If dumpdev was the same as the old primary swap
-	 * device, move it to the new primary swap device.
-	 */
-	if (temp == dumpdev)
-		dumpdev = swdevt[0].sw_dev;
-#endif
 }
diff --git a/sys/kern/init_main.c b/sys/kern/init_main.c
index 77f6803b24b1..41aefb97e5a4 100644
--- a/sys/kern/init_main.c
+++ b/sys/kern/init_main.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)init_main.c	8.9 (Berkeley) 1/21/94
- * $Id: init_main.c,v 1.22 1995/04/23 04:13:51 phk Exp $
+ * $Id: init_main.c,v 1.23 1995/05/04 08:21:24 davidg Exp $
  */
 
 #include <sys/param.h>
@@ -294,7 +294,6 @@ main(framep)
 	VREF(fdp->fd_fd.fd_cdir);
 	VOP_UNLOCK(rootvnode);
 	fdp->fd_fd.fd_rdir = NULL;
-	swapinit();
 
 	/*
 	 * Now can look at time, having had a chance to verify the time
diff --git a/sys/nfs/nfs_vfsops.c b/sys/nfs/nfs_vfsops.c
index 562c953fffda..7e3c6963b1e8 100644
--- a/sys/nfs/nfs_vfsops.c
+++ b/sys/nfs/nfs_vfsops.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)nfs_vfsops.c	8.3 (Berkeley) 1/4/94
- * $Id: nfs_vfsops.c,v 1.11 1995/03/16 18:15:40 bde Exp $
+ * $Id: nfs_vfsops.c,v 1.12 1995/03/16 20:23:46 wollman Exp $
  */
 
 #include <sys/param.h>
@@ -273,32 +273,15 @@ nfs_mountroot()
 		(void) nfs_mountdiskless(buf, "/swap", 0,
 		    &nd->swap_saddr, &nd->swap_args, &vp);
 
-		for (i=0;swdevt[i].sw_dev != NODEV;i++) ;
-
 		/*
 		 * Since the swap file is not the root dir of a file system,
 		 * hack it to a regular file.
 		 */
 		vp->v_type = VREG;
 		vp->v_flag = 0;
-		swapdev_vp = vp;
 		VREF(vp);
-		swdevt[i].sw_vp = vp;
-		swdevt[i].sw_nblks = nd->swap_nblks*2;
-
-		if (!swdevt[i].sw_nblks) {
-			swdevt[i].sw_nblks = 2048;
-			printf("defaulting to %d kbyte.\n",
-				swdevt[i].sw_nblks/2);
-		} else
-			printf("using %d kbyte.\n",swdevt[i].sw_nblks/2);
-	} else {
-	  /*
-	   * No NFS swap space was specified, try using local disk
-	   */
-	  if (bdevvp(swapdev, &swapdev_vp))
-	    panic("nfs_mountroot: can't setup bdevvp for swap");
-	}
+		swaponvp(p, vp, NODEV, nd->swap_nblks * 2);
+	} 
 
 	/*
 	 * Create the rootfs mount point.
diff --git a/sys/nfsclient/nfs_vfsops.c b/sys/nfsclient/nfs_vfsops.c
index 562c953fffda..7e3c6963b1e8 100644
--- a/sys/nfsclient/nfs_vfsops.c
+++ b/sys/nfsclient/nfs_vfsops.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)nfs_vfsops.c	8.3 (Berkeley) 1/4/94
- * $Id: nfs_vfsops.c,v 1.11 1995/03/16 18:15:40 bde Exp $
+ * $Id: nfs_vfsops.c,v 1.12 1995/03/16 20:23:46 wollman Exp $
  */
 
 #include <sys/param.h>
@@ -273,32 +273,15 @@ nfs_mountroot()
 		(void) nfs_mountdiskless(buf, "/swap", 0,
 		    &nd->swap_saddr, &nd->swap_args, &vp);
 
-		for (i=0;swdevt[i].sw_dev != NODEV;i++) ;
-
 		/*
 		 * Since the swap file is not the root dir of a file system,
 		 * hack it to a regular file.
 		 */
 		vp->v_type = VREG;
 		vp->v_flag = 0;
-		swapdev_vp = vp;
 		VREF(vp);
-		swdevt[i].sw_vp = vp;
-		swdevt[i].sw_nblks = nd->swap_nblks*2;
-
-		if (!swdevt[i].sw_nblks) {
-			swdevt[i].sw_nblks = 2048;
-			printf("defaulting to %d kbyte.\n",
-				swdevt[i].sw_nblks/2);
-		} else
-			printf("using %d kbyte.\n",swdevt[i].sw_nblks/2);
-	} else {
-	  /*
-	   * No NFS swap space was specified, try using local disk
-	   */
-	  if (bdevvp(swapdev, &swapdev_vp))
-	    panic("nfs_mountroot: can't setup bdevvp for swap");
-	}
+		swaponvp(p, vp, NODEV, nd->swap_nblks * 2);
+	} 
 
 	/*
 	 * Create the rootfs mount point.
diff --git a/sys/sys/conf.h b/sys/sys/conf.h
index 3619cc1630f6..10fbbd3adeb4 100644
--- a/sys/sys/conf.h
+++ b/sys/sys/conf.h
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)conf.h	8.3 (Berkeley) 1/21/94
- * $Id: conf.h,v 1.12 1995/04/23 09:36:59 bde Exp $
+ * $Id: conf.h,v 1.13 1995/05/12 19:17:24 wollman Exp $
  */
 
 #ifndef _SYS_CONF_H_
@@ -138,7 +138,6 @@ struct swdevt {
 #define sw_freed	sw_flags	/* XXX compat */
 
 #ifdef KERNEL
-extern struct swdevt swdevt[];
 extern int setdumpdev __P((dev_t));
 
 dev_t	chrtoblk __P((dev_t dev));
diff --git a/sys/sys/gmon.h b/sys/sys/gmon.h
index b2526cded509..471694d5d820 100644
--- a/sys/sys/gmon.h
+++ b/sys/sys/gmon.h
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)gmon.h	8.2 (Berkeley) 1/4/94
- * $Id: gmon.h,v 1.3 1995/01/29 06:23:34 bde Exp $
+ * $Id: gmon.h,v 1.4 1995/03/16 18:16:17 bde Exp $
  */
 
 #ifndef _SYS_GMON_H_
@@ -124,8 +124,8 @@ struct rawarc {
 /*
  * general rounding functions.
  */
-#define ROUNDDOWN(x,y)	(((x)/(y))*(y))
-#define ROUNDUP(x,y)	((((x)+(y)-1)/(y))*(y))
+#define ROUNDDOWN(x,y)	rounddown(x,y)
+#define ROUNDUP(x,y)	roundup(x,y)
 
 /*
  * The profiling data structures are housed in this structure.
diff --git a/sys/sys/linedisc.h b/sys/sys/linedisc.h
index 3619cc1630f6..10fbbd3adeb4 100644
--- a/sys/sys/linedisc.h
+++ b/sys/sys/linedisc.h
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)conf.h	8.3 (Berkeley) 1/21/94
- * $Id: conf.h,v 1.12 1995/04/23 09:36:59 bde Exp $
+ * $Id: conf.h,v 1.13 1995/05/12 19:17:24 wollman Exp $
  */
 
 #ifndef _SYS_CONF_H_
@@ -138,7 +138,6 @@ struct swdevt {
 #define sw_freed	sw_flags	/* XXX compat */
 
 #ifdef KERNEL
-extern struct swdevt swdevt[];
 extern int setdumpdev __P((dev_t));
 
 dev_t	chrtoblk __P((dev_t dev));
diff --git a/sys/sys/param.h b/sys/sys/param.h
index 0a13fb0c27f3..09cb1ce9ccd9 100644
--- a/sys/sys/param.h
+++ b/sys/sys/param.h
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)param.h	8.2 (Berkeley) 1/21/94
- * $Id: param.h,v 1.6 1995/01/09 16:05:13 davidg Exp $
+ * $Id: param.h,v 1.7 1995/02/07 03:33:05 davidg Exp $
  */
 
 #ifndef _SYS_PARAM_H_
@@ -180,6 +180,7 @@
 #ifndef howmany
 #define	howmany(x, y)	(((x)+((y)-1))/(y))
 #endif
+#define	rounddown(x, y)	(((x)/(y))*(y))
 #define	roundup(x, y)	((((x)+((y)-1))/(y))*(y))
 #define powerof2(x)	((((x)-1)&(x))==0)
 
diff --git a/sys/sys/systm.h b/sys/sys/systm.h
index c91dc4a9d725..5676b88033c8 100644
--- a/sys/sys/systm.h
+++ b/sys/sys/systm.h
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)systm.h	8.4 (Berkeley) 2/23/94
- * $Id: systm.h,v 1.19 1995/04/04 02:02:28 davidg Exp $
+ * $Id: systm.h,v 1.20 1995/05/02 05:35:07 davidg Exp $
  */
 
 #ifndef _SYS_SYSTM_H_
@@ -81,6 +81,7 @@ extern char copyright[];	/* system copyright */
 
 extern int nblkdev;		/* number of entries in bdevsw */
 extern int nchrdev;		/* number of entries in cdevsw */
+extern struct swdevt *swdevt;	/* swap-device information */
 extern int nswdev;		/* number of swap devices */
 extern int nswap;		/* size of swap space */
 
diff --git a/sys/vm/swap_pager.c b/sys/vm/swap_pager.c
index 32f97a5ae1ce..e86e7009e11f 100644
--- a/sys/vm/swap_pager.c
+++ b/sys/vm/swap_pager.c
@@ -39,7 +39,7 @@
  * from: Utah $Hdr: swap_pager.c 1.4 91/04/30$
  *
  *	@(#)swap_pager.c	8.9 (Berkeley) 3/21/94
- * $Id: swap_pager.c,v 1.37 1995/05/07 06:36:59 dyson Exp $
+ * $Id: swap_pager.c,v 1.38 1995/05/10 18:56:02 davidg Exp $
  */
 
 /*
@@ -103,7 +103,7 @@ struct swpagerclean {
 
 #define SWB_EMPTY (-1)
 
-struct swpclean swap_pager_done;	/* list of compileted page cleans */
+struct swpclean swap_pager_done;	/* list of completed page cleans */
 struct swpclean swap_pager_inuse;	/* list of pending page cleans */
 struct swpclean swap_pager_free;	/* list of free pager clean structs */
 struct pagerlst swap_pager_list;	/* list of "named" anon regions */
diff --git a/sys/vm/vm_extern.h b/sys/vm/vm_extern.h
index fb752c157d2d..997f41a0e21d 100644
--- a/sys/vm/vm_extern.h
+++ b/sys/vm/vm_extern.h
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)vm_extern.h	8.2 (Berkeley) 1/12/94
- * $Id: vm_extern.h,v 1.13 1995/03/16 18:17:08 bde Exp $
+ * $Id: vm_extern.h,v 1.14 1995/05/10 18:56:04 davidg Exp $
  */
 
 #ifndef _VM_EXTERN_H_
@@ -98,10 +98,9 @@ void loadav __P((struct loadavg *));
 void munmapfd __P((struct proc *, int));
 int pager_cache __P((vm_object_t, boolean_t));
 void sched __P((void));
-void swapinit __P((void));
+int swaponvp __P((struct proc *, struct vnode *, dev_t , u_long ));
 void swapout __P((struct proc *));
 void swapout_threads __P((void));
-int swfree __P((struct proc *, int));
 void swstrategy __P((struct buf *));
 void thread_block __P((char *));
 void thread_sleep __P((int, simple_lock_t, boolean_t));
diff --git a/sys/vm/vm_swap.c b/sys/vm/vm_swap.c
index 4f8f48396002..682d11a953a9 100644
--- a/sys/vm/vm_swap.c
+++ b/sys/vm/vm_swap.c
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)vm_swap.c	8.5 (Berkeley) 2/17/94
- * $Id: vm_swap.c,v 1.15 1995/03/16 18:17:33 bde Exp $
+ * $Id: vm_swap.c,v 1.16 1995/05/12 03:54:59 phk Exp $
  */
 
 #include <sys/param.h>
@@ -53,72 +53,17 @@
  * Indirect driver for multi-controller paging.
  */
 
-int nswap, nswdev;
+#ifndef NSWAPDEV
+#define NSWAPDEV	4
+#endif
+static struct swdevt should_be_malloced[NSWAPDEV];
+struct swdevt *swdevt = should_be_malloced;
+int nswap;
+int nswdev = NSWAPDEV;
 int vm_swap_size;
 int bswneeded;
 vm_offset_t swapbkva;		/* swap buffers kva */
 
-/*
- * Set up swap devices.
- * Initialize linked list of free swap
- * headers. These do not actually point
- * to buffers, but rather to pages that
- * are being swapped in and out.
- */
-void
-swapinit()
-{
-	register struct proc *p = &proc0;	/* XXX */
-	struct swdevt *swp;
-	int error;
-
-	/*
-	 * Count swap devices, and adjust total swap space available. Some of
-	 * the space will not be countable until later (dynamically
-	 * configurable devices) and some of the counted space will not be
-	 * available until a swapon() system call is issued, both usually
-	 * happen when the system goes multi-user.
-	 * 
-	 * If using NFS for swap, swdevt[0] will already be bdevvp'd.	XXX
-	 */
-	nswdev = 0;
-	nswap = 0;
-	for (swp = swdevt; swp->sw_dev != NODEV || swp->sw_vp != NULL; swp++) {
-		nswdev++;
-		if (swp->sw_nblks > nswap)
-			nswap = swp->sw_nblks;
-	}
-	if (nswdev == 0)
-		panic("swapinit");
-	if (nswdev > 1)
-		nswap = ((nswap + dmmax - 1) / dmmax) * dmmax;
-	nswap *= nswdev;
-	if (swdevt[0].sw_vp == NULL &&
-	    bdevvp(swdevt[0].sw_dev, &swdevt[0].sw_vp))
-		panic("swapvp");
-	/*
-	 * If there is no swap configured, tell the user. We don't
-	 * automatically activate any swapspaces in the kernel; the user must
-	 * explicitly use swapon to enable swaping on a device.
-	 */
-	if (nswap == 0)
-		printf("WARNING: no swap space found\n");
-	for (swp = swdevt;; swp++) {
-		if (swp->sw_dev == NODEV) {
-			if (swp->sw_vp == NULL)
-				break;
-
-			/* We DO enable NFS swapspaces */
-			error = swfree(p, swp - swdevt);
-			if (error) {
-				printf(
-				    "Couldn't enable swapspace %d, error = %d",
-				    swp - swdevt, error);
-			}
-		}
-	}
-}
-
 void
 swstrategy(bp)
 	register struct buf *bp;
@@ -194,43 +139,53 @@ swapon(p, uap, retval)
 	register struct vnode *vp;
 	register struct swdevt *sp;
 	dev_t dev;
-	int error;
+	int error,i;
 	struct nameidata nd;
+	struct vattr attr;
 
 	error = suser(p->p_ucred, &p->p_acflag);
 	if (error)
 		return (error);
+
 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, uap->name, p);
 	error = namei(&nd);
 	if (error)
 		return (error);
+
 	vp = nd.ni_vp;
-	if (vp->v_type != VBLK) {
-		vrele(vp);
-		return (ENOTBLK);
-	}
-	dev = (dev_t) vp->v_rdev;
-	if (major(dev) >= nblkdev) {
-		vrele(vp);
-		return (ENXIO);
-	}
-	for (sp = &swdevt[0]; sp->sw_dev != NODEV; sp++) {
-		if (sp->sw_dev == dev) {
-			if (sp->sw_flags & SW_FREED) {
-				vrele(vp);
-				return (EBUSY);
-			}
-			sp->sw_vp = vp;
-			error = swfree(p, sp - swdevt);
-			if (error) {
-				vrele(vp);
-				return (error);
-			}
-			return (0);
+
+	switch (vp->v_type) {
+	case VBLK:
+		dev = (dev_t) vp->v_rdev;
+		if (major(dev) >= nblkdev) {
+			error = ENXIO;
+			break;
 		}
+		error = swaponvp(p, vp, dev, 0);
+		break;
+	case VCHR:
+		/*
+		 * For now, we disallow swapping to regular files.
+		 * It requires logical->physcal block translation
+		 * support in the swap pager before it will work.
+		 */
+		error = ENOTBLK;
+		break;
+#if 0
+		error = VOP_GETATTR(vp, &attr, p->p_ucred, p);
+		if (!error)
+			error = swaponvp(p, vp, NODEV, attr.va_size / DEV_BSIZE);
+		break;
+#endif
+	default:
+		error = EINVAL;
+		break;
 	}
-	vrele(vp);
-	return (EINVAL);
+
+	if (error)
+		vrele(vp);
+
+	return (error);
 }
 
 /*
@@ -240,49 +195,54 @@ swapon(p, uap, retval)
  * among the devices.
  */
 int
-swfree(p, index)
+swaponvp(p, vp, dev, nblks)
 	struct proc *p;
-	int index;
+	struct vnode *vp;
+	dev_t dev;
+	u_long nblks;
 {
+	int index;
 	register struct swdevt *sp;
 	register swblk_t vsbase;
 	register long blk;
-	struct vnode *vp;
-	register swblk_t dvbase;
-	register int nblks;
+	swblk_t dvbase;
+	struct swdevt *swp;
 	int error;
+	int perdev;
+
+	for (sp = swdevt, index = 0 ; index < nswdev; index++, sp++) {
+		if (sp->sw_vp == vp)
+			return EBUSY;
+		if (!sp->sw_vp)
+			goto found;
+
+	}
+	return EINVAL;
+    found:
+	if (dev != NODEV && (major(dev) >= nblkdev))
+		return (ENXIO);
 
-	sp = &swdevt[index];
-	vp = sp->sw_vp;
 	error = VOP_OPEN(vp, FREAD | FWRITE, p->p_ucred, p);
 	if (error)
 		return (error);
-	sp->sw_flags |= SW_FREED;
-	nblks = sp->sw_nblks;
-	/*
-	 * Some devices may not exist til after boot time. If so, their nblk
-	 * count will be 0.
-	 */
-	if (nblks <= 0) {
-		int perdev;
-		dev_t dev = sp->sw_dev;
-
-		if (bdevsw[major(dev)].d_psize == 0 ||
-		    (nblks = (*bdevsw[major(dev)].d_psize) (dev)) == -1) {
-			(void) VOP_CLOSE(vp, FREAD | FWRITE, p->p_ucred, p);
-			sp->sw_flags &= ~SW_FREED;
-			return (ENXIO);
-		}
-		perdev = nswap / nswdev;
-		if (nblks > perdev)
-			nblks = perdev;
-		sp->sw_nblks = nblks;
+	
+	if (nblks == 0 && (bdevsw[major(dev)].d_psize == 0 ||
+	    (nblks = (*bdevsw[major(dev)].d_psize) (dev)) == -1)) {
+		(void) VOP_CLOSE(vp, FREAD | FWRITE, p->p_ucred, p);
+		return (ENXIO);
 	}
 	if (nblks == 0) {
 		(void) VOP_CLOSE(vp, FREAD | FWRITE, p->p_ucred, p);
-		sp->sw_flags &= ~SW_FREED;
-		return (0);	/* XXX error? */
+		return (ENXIO);
 	}
+	sp->sw_vp = vp;
+	sp->sw_dev = dev;
+	sp->sw_flags |= SW_FREED;
+	sp->sw_nblks = nblks;
+
+	if (nblks * nswdev > nswap)
+		nswap = nblks * nswdev;
+
 	for (dvbase = dmmax; dvbase < nblks; dvbase += dmmax) {
 		blk = nblks - dvbase;