kernel: introduce devswap #¶ to serve /dev/swap and handle swapfile encryption

lib/namespace

@@ -10,6 +10,7 @@ bind #p /proc
 bind -c #s /srv
 bind -q #σ /shr
 bind -a #¤ /dev
+bind -qa #¶ /dev
 
 # authentication
 mount -b /srv/factotum /mnt

sys/man/3/cons

@@ -22,7 +22,6 @@ cons \- console, clocks, process/process group ids, user, null, reboot, etc.
 .B /dev/ppid
 .B /dev/random
 .B /dev/reboot
-.B /dev/swap
 .B /dev/sysname
 .B /dev/sysstat
 .B /dev/time
@@ -240,41 +239,6 @@ Writing anything to
 .B sysstat
 resets all of the counts on all processors.
 .PP
-The
-.B swap
-device holds a text block giving memory usage statistics:
-.IP
-.EX
-\fIn\fP memory
-\fIn\fP pagesize
-\fIn\fP kernel
-\fIn\fP/\fIm\fP user
-\fIn\fP/\fIm\fP swap
-\fIa\fP/\fIn\fP/\fIm\fP kernel malloc
-\fIa\fP/\fIn\fP/\fIm\fP kernel draw
-.EE
-.PP
-These are total memory (bytes), system page size (bytes),
-kernel memory (pages), user memory (pages), swap space (pages),
-kernel malloced data (bytes), and kernel graphics data (bytes).
-The expression
-.IR n / m
-indicates
-.I n
-used out of
-.I m
-available.
-For kernel malloc and kernel draw,
-.IR a
-indicates the current allocation in bytes.
-These numbers are not blank padded.
-.PP
-To turn on swapping, write to
-.B swap
-the textual file descriptor number of a file or device on which to swap.
-See
-.IR swap (8).
-.PP
 Reads and writes to
 .IR mordor
 will inevitably cause the front to fall off.

sys/man/3/swap

@@ -0,0 +1,46 @@
+.TH SWAP 3
+.SH NAME
+swap \- memory usage statistics and pagefile control
+.SH SYNOPSIS
+.nf
+.B bind -a #¶ /dev
+
+.B /dev/swap
+.fi
+.SH DESCRIPTION
+The
+.B swap
+device holds a text block giving memory usage statistics:
+.IP
+.EX
+\fIn\fP memory
+\fIn\fP pagesize
+\fIn\fP kernel
+\fIn\fP/\fIm\fP user
+\fIn\fP/\fIm\fP swap
+\fIa\fP/\fIn\fP/\fIm\fP kernel malloc
+\fIa\fP/\fIn\fP/\fIm\fP kernel draw
+.EE
+.PP
+These are total memory (bytes), system page size (bytes),
+kernel memory (pages), user memory (pages), swap space (pages),
+kernel malloced data (bytes), and kernel graphics data (bytes).
+The expression
+.IR n / m
+indicates
+.I n
+used out of
+.I m
+available.
+For kernel malloc and kernel draw,
+.IR a
+indicates the current allocation in bytes.
+These numbers are not blank padded.
+.PP
+To turn on swapping, write to
+.B swap
+the textual file descriptor number of a file or device on which to swap.
+.SH SEE ALSO
+.IR swap (8).
+.SH SOURCE
+.B /sys/src/9/port/devswap.c

sys/man/8/swap

@@ -35,4 +35,5 @@ will lead to deadlock if the process isn't made non-swappable
 ctl-message in
 .IR proc (3)).
 .SH "SEE ALSO"
+.IR swap (3),
 .IR proc (3)

sys/src/9/bcm/main.c

@@ -270,7 +270,6 @@ main(void)
 	links();
 	chandevreset();			/* most devices are discovered here */
 	pageinit();
-	swapinit();
 	userinit();
 	gpiomeminit();
 	schedinit();

sys/src/9/bcm/mkfile

@@ -33,7 +33,6 @@ PORT=\
 	rdb.$O\
 	rebootcmd.$O\
 	segment.$O\
-	swap.$O\
 	syscallfmt.$O\
 	sysfile.$O\
 	sysproc.$O\

sys/src/9/bcm/picpuf

@@ -1,6 +1,7 @@
 dev
 	root
 	cons
+	swap
 	env
 	pipe
 	proc

sys/src/9/bcm/pif

@@ -1,6 +1,7 @@
 dev
 	root
 	cons
+	swap
 	env
 	pipe
 	proc

sys/src/9/boot/bootrc

@@ -10,7 +10,7 @@ unmount /root
 
 bind -q '#d' /fd
 bind -q '#p' /proc
-for(i in S f k æ t b m)
+for(i in ¶ P S f k æ t b m)
 	bind -qa '#'^$i /dev
 
 # bind in an ip interface

sys/src/9/kw/main.c

@@ -322,7 +322,6 @@ wave(' ');
 	chandevreset();			/* most devices are discovered here */
 
 	pageinit();
-	swapinit();
 	userinit();
 	schedinit();
 	panic("schedinit returned");

sys/src/9/kw/mkfile

@@ -32,7 +32,6 @@ PORT=\
 	qio.$O\
 	qlock.$O\
 	segment.$O\
-	swap.$O\
 	syscallfmt.$O\
 	sysfile.$O\
 	sysproc.$O\

sys/src/9/kw/plug

@@ -3,6 +3,7 @@
 dev
 	root
 	cons
+	swap
 	env
 	pipe
 	proc

sys/src/9/mtx/main.c

@@ -35,7 +35,6 @@ main(void)
 	links();
 	chandevreset();
 	pageinit();
-	swapinit();
 	fpsave(&initfp);
 	initfp.fpscr = 0;
 	userinit();

sys/src/9/mtx/mkfile

@@ -30,7 +30,6 @@ PORT=\
 	qlock.$O\
 	rdb.$O\
 	segment.$O\
-	swap.$O\
 	sysfile.$O\
 	sysproc.$O\
 	taslock.$O\

sys/src/9/mtx/mtx

@@ -1,6 +1,7 @@
 dev
 	root
 	cons
+	swap
 	arch
 	pnp		pci
 	env

sys/src/9/mtx/mtxcpu

@@ -1,6 +1,7 @@
 dev
 	root
 	cons
+	swap
 	arch
 	pnp		pci
 	env

sys/src/9/omap/beagle

@@ -2,6 +2,7 @@
 dev
 	root
 	cons
+	swap
 	env
 	pipe
 	proc

sys/src/9/omap/main.c

@@ -276,7 +276,6 @@ wave('l');
 //	i8250console();			/* too early; see init0 */
 
 	pageinit();
-	swapinit();
 	userinit();
 	schedinit();
 }

sys/src/9/omap/mkfile

@@ -33,7 +33,6 @@ PORT=\
 	qio.$O\
 	qlock.$O\
 	segment.$O\
-	swap.$O\
 	sysfile.$O\
 	sysproc.$O\
 	taslock.$O\

sys/src/9/pc/main.c

@@ -62,7 +62,6 @@ main(void)
 	chandevreset();
 	netconsole();
 	pageinit();
-	swapinit();
 	userinit();
 	schedinit();
 }

sys/src/9/pc/mkfile

@@ -35,7 +35,6 @@ PORT=\
 	rdb.$O\
 	rebootcmd.$O\
 	segment.$O\
-	swap.$O\
 	syscallfmt.$O\
 	sysfile.$O\
 	sysproc.$O\

sys/src/9/pc/pc

@@ -2,6 +2,7 @@
 dev
 	root
 	cons
+	swap
 	arch
 	pnp		pci
 	env

sys/src/9/pc64/main.c

@@ -332,7 +332,6 @@ main()
 	netconsole();
 	preallocpages();
 	pageinit();
-	swapinit();
 	userinit();
 	schedinit();
 }

sys/src/9/pc64/mkfile

@@ -33,7 +33,6 @@ PORT=\
 	rdb.$O\
 	rebootcmd.$O\
 	segment.$O\
-	swap.$O\
 	syscallfmt.$O\
 	sysfile.$O\
 	sysproc.$O\

sys/src/9/pc64/pc64

@@ -2,6 +2,7 @@
 dev
 	root
 	cons
+	swap
 	arch
 	pnp		pci
 	env

sys/src/9/port/devcons.c

@@ -5,7 +5,6 @@
 #include	"fns.h"
 #include	"../port/error.h"
 
-#include	<pool.h>
 #include	<authsrv.h>
 
 void	(*consdebug)(void) = nil;
@@ -324,7 +323,6 @@ enum{
 	Qppid,
 	Qrandom,
 	Qreboot,
-	Qswap,
 	Qsysname,
 	Qsysstat,
 	Qtime,
@@ -357,7 +355,6 @@ static Dirtab consdir[]={
 	"ppid",		{Qppid},	NUMSIZE,	0444,
 	"random",	{Qrandom},	0,		0444,
 	"reboot",	{Qreboot},	0,		0664,
-	"swap",		{Qswap},	0,		0664,
 	"sysname",	{Qsysname},	0,		0664,
 	"sysstat",	{Qsysstat},	0,		0666,
 	"time",		{Qtime},	NUMSIZE+3*VLNUMSIZE,	0664,
@@ -471,8 +468,6 @@ consread(Chan *c, void *buf, long n, vlong off)
 	int i, k, id;
 	vlong offset = off;
 	extern char configfile[];
-	extern Image fscache;
-	extern Image swapimage;
 
 	if(n <= 0)
 		return n;
@@ -592,33 +587,6 @@ consread(Chan *c, void *buf, long n, vlong off)
 		poperror();
 		return n;
 
-	case Qswap:
-		snprint(tmp, sizeof tmp,
-			"%llud memory\n"
-			"%llud pagesize\n"
-			"%lud kernel\n"
-			"%lud/%lud user\n"
-			"%lud/%lud swap\n"
-			"%llud/%llud/%llud kernel malloc\n"
-			"%llud/%llud/%llud kernel draw\n"
-			"%llud/%llud/%llud kernel secret\n",
-			(uvlong)conf.npage*BY2PG,
-			(uvlong)BY2PG,
-			conf.npage-conf.upages,
-			palloc.user-palloc.freecount-fscache.pgref-swapimage.pgref, palloc.user,
-			conf.nswap-swapalloc.free, conf.nswap,
-			(uvlong)mainmem->curalloc,
-			(uvlong)mainmem->cursize,
-			(uvlong)mainmem->maxsize,
-			(uvlong)imagmem->curalloc,
-			(uvlong)imagmem->cursize,
-			(uvlong)imagmem->maxsize,
-			(uvlong)secrmem->curalloc,
-			(uvlong)secrmem->cursize,
-			(uvlong)secrmem->maxsize);
-
-		return readstr((ulong)offset, buf, n, tmp);
-
 	case Qsysname:
 		if(sysname == nil)
 			return 0;
@@ -669,8 +637,7 @@ conswrite(Chan *c, void *va, long n, vlong off)
 	long l, bp;
 	char *a;
 	Mach *mp;
-	int id, fd;
-	Chan *swc;
+	int id;
 	ulong offset;
 	Cmdbuf *cb;
 	Cmdtab *ct;
@@ -765,25 +732,6 @@ conswrite(Chan *c, void *va, long n, vlong off)
 		}
 		break;
 
-	case Qswap:
-		if(n >= sizeof buf)
-			error(Egreg);
-		memmove(buf, va, n);	/* so we can NUL-terminate */
-		buf[n] = 0;
-		/* start a pager if not already started */
-		if(strncmp(buf, "start", 5) == 0){
-			kickpager();
-			break;
-		}
-		if(!iseve())
-			error(Eperm);
-		if(buf[0]<'0' || '9'<buf[0])
-			error(Ebadarg);
-		fd = strtoul(buf, 0, 0);
-		swc = fdtochan(fd, ORDWR, 1, 1);
-		setswapchan(swc);
-		break;
-
 	case Qsysname:
 		if(offset != 0)
 			error(Ebadarg);

sys/src/9/port/devswap.c

@@ -5,21 +5,29 @@
 #include	"fns.h"
 #include	"../port/error.h"
 
+#include	<libsec.h>
+#include	<pool.h>
+
 static int	canflush(Proc*, Segment*);
 static void	executeio(void);
 static void	pageout(Proc*, Segment*);
 static void	pagepte(int, Page**);
 static void	pager(void*);
 
-Image 	swapimage;
+Image 	swapimage = {
+	.notext = 1,
+};
+
+static Chan	*swapchan;
+static uchar	*swapbuf;
+static AESstate *swapkey;
 
-static 	int	swopen;
 static Page	**iolist;
 static int	ioptr;
 
 static ushort	ageclock;
 
-void
+static void
 swapinit(void)
 {
 	swapalloc.swmap = xalloc(conf.nswap);
@@ -30,10 +38,8 @@ swapinit(void)
 	swapalloc.xref = 0;
 
 	iolist = xalloc(conf.nswppo*sizeof(Page*));
-	if(swapalloc.swmap == 0 || iolist == 0)
+	if(swapalloc.swmap == nil || iolist == nil)
 		panic("swapinit: not enough memory");
-
-	swapimage.notext = 1;
 }
 
 static uintptr
@@ -216,13 +222,8 @@ pageout(Proc *p, Segment *s)
 	if(!canqlock(s))	/* We cannot afford to wait, we will surely deadlock */
 		return;
 
-	if(!canflush(p, s)) {	/* Able to invalidate all tlbs with references */
-		qunlock(s);
-		putseg(s);
-		return;
-	}
-
-	if(waserror()) {
+	if(!canflush(p, s)	/* Able to invalidate all tlbs with references */
+	|| waserror()) {
 		qunlock(s);
 		putseg(s);
 		return;
@@ -389,10 +390,10 @@ needpages(void*)
 	return palloc.freecount < swapalloc.headroom;
 }
 
-void
+static void
 setswapchan(Chan *c)
 {
-	uchar dirbuf[sizeof(Dir)+100];
+	uchar buf[sizeof(Dir)+100];
 	Dir d;
 	int n;
 
@@ -412,8 +413,8 @@ setswapchan(Chan *c)
 	 *  to be at most the size of the partition
 	 */
 	if(devtab[c->type]->dc != L'M'){
-		n = devtab[c->type]->stat(c, dirbuf, sizeof dirbuf);
-		if(n <= 0 || convM2D(dirbuf, n, &d, nil) == 0)
+		n = devtab[c->type]->stat(c, buf, sizeof buf);
+		if(n <= 0 || convM2D(buf, n, &d, nil) == 0)
 			error("stat failed in setswapchan");
 		if(d.length < conf.nswppo*BY2PG)
 			error("swap device too small");
@@ -425,6 +426,187 @@ setswapchan(Chan *c)
 	}
 	c->flag &= ~CCACHE;
 	cclunk(c);
-	swapimage.c = c;
 	poperror();
+
+	swapchan = c;
+	swapimage.c = namec("#¶/swapfile", Aopen, ORDWR, 0);
 }
+
+enum {
+	Qdir,
+	Qswap,
+	Qswapfile,
+};
+
+static Dirtab swapdir[]={
+	".",		{Qdir, 0, QTDIR},	0,		DMDIR|0555,
+	"swap",		{Qswap},		0,		0664,
+	"swapfile",	{Qswapfile},		0,		0600,
+};
+
+static Chan*
+swapattach(char *spec)
+{
+	return devattach(L'¶', spec);
+}
+
+static Walkqid*
+swapwalk(Chan *c, Chan *nc, char **name, int nname)
+{
+	return devwalk(c, nc, name, nname, swapdir, nelem(swapdir), devgen);
+}
+
+static int
+swapstat(Chan *c, uchar *dp, int n)
+{
+	return devstat(c, dp, n, swapdir, nelem(swapdir), devgen);
+}
+
+static Chan*
+swapopen(Chan *c, int omode)
+{
+	uchar key[128/8];
+
+	switch((ulong)c->qid.path){
+	case Qswapfile:
+		if(!iseve() || omode != ORDWR)
+			error(Eperm);
+		if(swapimage.c != nil)
+			error(Einuse);
+		if(swapchan == nil)
+			error(Egreg);
+
+		c->mode = openmode(omode);
+		c->flag |= COPEN;
+		c->offset = 0;
+
+		swapbuf = mallocalign(BY2PG, BY2PG, 0, 0);
+		swapkey = secalloc(sizeof(AESstate)*2);
+		if(swapbuf == nil || swapkey == nil)
+			error(Enomem);
+
+		genrandom(key, sizeof(key));
+		setupAESstate(&swapkey[0], key, sizeof(key), nil);
+		genrandom(key, sizeof(key));
+		setupAESstate(&swapkey[1], key, sizeof(key), nil);
+		memset(key, 0, sizeof(key));
+
+		return c;
+	}
+	return devopen(c, omode, swapdir, nelem(swapdir), devgen);
+}
+
+static void
+swapclose(Chan *c)
+{
+	if((c->flag & COPEN) == 0)
+		return;
+	switch((ulong)c->qid.path){
+	case Qswapfile:
+		cclose(swapchan);
+		swapchan = nil;
+		secfree(swapkey);
+		swapkey = nil;
+		free(swapbuf);
+		swapbuf = nil;
+		break;
+	}
+}
+
+static long
+swapread(Chan *c, void *va, long n, vlong off)
+{
+	char tmp[256];		/* must be >= 18*NUMSIZE (Qswap) */
+
+	switch((ulong)c->qid.path){
+	case Qdir:
+		return devdirread(c, va, n, swapdir, nelem(swapdir), devgen);
+	case Qswap:
+		snprint(tmp, sizeof tmp,
+			"%llud memory\n"
+			"%llud pagesize\n"
+			"%lud kernel\n"
+			"%lud/%lud user\n"
+			"%lud/%lud swap\n"
+			"%llud/%llud/%llud kernel malloc\n"
+			"%llud/%llud/%llud kernel draw\n"
+			"%llud/%llud/%llud kernel secret\n",
+			(uvlong)conf.npage*BY2PG,
+			(uvlong)BY2PG,
+			conf.npage-conf.upages,
+			palloc.user-palloc.freecount-fscache.pgref-swapimage.pgref, palloc.user,
+			conf.nswap-swapalloc.free, conf.nswap,
+			(uvlong)mainmem->curalloc,
+			(uvlong)mainmem->cursize,
+			(uvlong)mainmem->maxsize,
+			(uvlong)imagmem->curalloc,
+			(uvlong)imagmem->cursize,
+			(uvlong)imagmem->maxsize,
+			(uvlong)secrmem->curalloc,
+			(uvlong)secrmem->cursize,
+			(uvlong)secrmem->maxsize);
+		return readstr((ulong)off, va, n, tmp);
+	case Qswapfile:
+		if(n != BY2PG)
+			error(Ebadarg);
+		if(devtab[swapchan->type]->read(swapchan, va, n, off) != n)
+			error(Eio);
+		aes_xts_decrypt(&swapkey[0], &swapkey[1], off, va, va, n);
+		return n;
+	}
+	error(Egreg);
+	return 0;
+}
+
+static long
+swapwrite(Chan *c, void *va, long n, vlong off)
+{
+	char buf[256];
+	
+	switch((ulong)c->qid.path){
+	case Qswap:
+		if(!iseve())
+			error(Eperm);
+		if(n >= sizeof buf)
+			error(Egreg);
+		memmove(buf, va, n);	/* so we can NUL-terminate */
+		buf[n] = 0;
+		/* start a pager if not already started */
+		if(strncmp(buf, "start", 5) == 0)
+			kickpager();
+		else if(buf[0]>='0' && '9'<=buf[0])
+			setswapchan(fdtochan(strtoul(buf, nil, 0), ORDWR, 1, 1));
+		else
+			error(Ebadctl);
+		return n;
+	case Qswapfile:
+		if(n != BY2PG)
+			error(Ebadarg);
+		aes_xts_encrypt(&swapkey[0], &swapkey[1], off, va, swapbuf, n);
+		if(devtab[swapchan->type]->write(swapchan, swapbuf, n, off) != n)
+			error(Eio);
+		return n;
+	}
+	error(Egreg);
+	return 0;
+}
+
+Dev swapdevtab = {
+	L'¶',
+	"swap",
+	devreset,
+	swapinit,
+	devshutdown,
+	swapattach,
+	swapwalk,
+	swapstat,
+	swapopen,
+	devcreate,
+	swapclose,
+	swapread,
+	devbread,
+	swapwrite,
+	devbwrite,
+	devremove,
+	devwstat,
+};

sys/src/9/port/portfns.h

@@ -318,7 +318,6 @@ int		setlabel(Label*);
 void		setmalloctag(void*, uintptr);
 void		setrealloctag(void*, uintptr);
 void		setregisters(Ureg*, char*, char*, int);
-void		setswapchan(Chan*);
 void		setupwatchpts(Proc*, Watchpt*, int);
 char*		skipslash(char*);
 void		sleep(Rendez*, int(*)(void*), void*);
@@ -332,7 +331,6 @@ void		srvrenameuser(char*, char*);
 void		shrrenameuser(char*, char*);
 int		swapcount(uintptr);
 int		swapfull(void);
-void		swapinit(void);
 void		syscallfmt(ulong syscallno, uintptr pc, va_list list);
 void		sysretfmt(ulong syscallno, va_list list, uintptr ret, uvlong start, uvlong stop);
 void		timeradd(Timer*);

sys/src/9/port/portmkfile

@@ -62,15 +62,15 @@ errstr.h:	../port/mkerrstr ../port/error.h
 %.db:		main.$O
 	$CC -s$stem main.c | dbfmt > $stem.db
 
-alloc.$O:	/sys/include/pool.h
+alloc.$O devswap.$O:	/sys/include/pool.h
 devmnt.$O:	/sys/include/fcall.h
 proc.$O proc.acid:	errstr.h
 devroot.$O:	errstr.h
 devaudio.$O:	../port/audioif.h
-devaoe.$O:	/$objtype/include/ureg.h
-devfs.$O:	/$objtype/include/ureg.h
-devsd.$O:	/$objtype/include/ureg.h
-sdscsi.$O:	/$objtype/include/ureg.h
+devaoe.$O:	../port/sd.h /$objtype/include/ureg.h
+devfs.$O:	../port/sd.h /$objtype/include/ureg.h
+devsd.$O:	../port/sd.h /$objtype/include/ureg.h
+sdscsi.$O:	../port/sd.h /$objtype/include/ureg.h
 trap.$O:	/$objtype/include/ureg.h
 devproc.$O:	/$objtype/include/ureg.h
 main.$O:	init.h
@@ -87,3 +87,5 @@ unthwack.$O:	../port/thwack.h
 devsdp.$O:	../port/thwack.h
 devproc.$O sysproc.$O:	/sys/include/tos.h
 devproc.$O edf.$O proc.$O: /sys/include/trace.h
+devcons.$O:	/sys/include/authsrv.h
+devcap.$O devfs.$O devsdp.$O devssl.$O devtls.$O devswap.$O random.$O: /sys/include/libsec.h

sys/src/9/ppc/blast

@@ -1,6 +1,7 @@
 dev
 	root
 	cons
+	swap
 	env
 	flash
 	pipe

sys/src/9/ppc/main.c

@@ -84,7 +84,6 @@ main(void)
 	links();
 	chandevreset();
 	pageinit();
-	swapinit();
 	sharedseginit();
 	fpsave(&initfp);
 	initfp.fpscr = 0;

sys/src/9/ppc/mkfile

@@ -31,7 +31,6 @@ PORT=\
 	qlock.$O\
 	rdb.$O\
 	segment.$O\
-	swap.$O\
 	sysfile.$O\
 	sysproc.$O\
 	taslock.$O\

sys/src/9/sgi/indy

@@ -1,6 +1,7 @@
 dev
 	root
 	cons
+	swap
 	uart
 	mnt
 	srv

sys/src/9/sgi/main.c

@@ -192,8 +192,6 @@ main(void)
 	initseg();
 	links();
 	chandevreset();
-
-	swapinit();
 	userinit();
 	schedinit();
 	panic("schedinit returned");

sys/src/9/sgi/mkfile

@@ -38,7 +38,6 @@ PORT=\
 	rdb.$O\
 	rebootcmd.$O\
 	segment.$O\
-	swap.$O\
 	syscallfmt.$O\
 	sysfile.$O\
 	sysproc.$O\

sys/src/9/teg2/main.c

@@ -455,7 +455,6 @@ main(void)
 //	i8250console();			/* too early; see init0 */
 
 	pageinit();			/* prints "1020M memory: ⋯ */
-	swapinit();
 	userinit();
 
 	/*

sys/src/9/teg2/mkfile

@@ -34,7 +34,6 @@ PORT=\
 	qio.$O\
 	qlock.$O\
 	segment.$O\
-	swap.$O\
 	syscallfmt.$O\
 	sysfile.$O\
 	sysproc.$O\

sys/src/9/teg2/ts

@@ -2,6 +2,7 @@
 dev
 	root
 	cons
+	swap
 	env
 	pipe
 	proc

sys/src/9/xen/main.c

@@ -103,8 +103,6 @@ main(void)
 //	conf.monitor = 1;
 	chandevreset();
 	pageinit();
-
-	swapinit();
 	userinit();
 	schedinit();
 }

sys/src/9/xen/mkfile

@@ -32,7 +32,6 @@ PORT=\
 	qlock.$O\
 	rebootcmd.$O\
 	segment.$O\
-	swap.$O\
 	sysfile.$O\
 	sysproc.$O\
 	taslock.$O\

sys/src/9/xen/xenpcf

@@ -1,6 +1,7 @@
 dev
 	root		netif
 	cons
+	swap
 	uart
 	arch
 	env

sys/src/9/zynq/main.c

@@ -393,7 +393,6 @@ main(void)
 	archinit();
 	chandevreset();
 	pageinit();
-	swapinit();
 	screeninit();
 	userinit();
 	schedinit();

sys/src/9/zynq/mkfile

@@ -31,7 +31,6 @@ PORT=\
 	qio.$O\
 	qlock.$O\
 	segment.$O\
-	swap.$O\
 	sysfile.$O\
 	sysproc.$O\
 	taslock.$O\

sys/src/9/zynq/zynq

@@ -1,6 +1,7 @@
 dev
 	root
 	cons
+	swap
 	arch
 	uart
 	mnt