diff --git a/sys/src/cmd/cwfs/all.h b/sys/src/cmd/cwfs/all.h
index 89a15bea5..1cf878b04 100644
--- a/sys/src/cmd/cwfs/all.h
+++ b/sys/src/cmd/cwfs/all.h
@@ -10,8 +10,6 @@
 #include "dat.h"
 #include "portfns.h"
 
-#define malloc(n)	ialloc(n, 0)
-
 #define	CHAT(cp) ((cons.flags&chatflag) || \
 			((cp) && (((Chan*)(cp))->flags&chatflag)))
 #define	QID9P1(a,b)	(Qid9p1){a,b}
diff --git a/sys/src/cmd/cwfs/chk.c b/sys/src/cmd/cwfs/chk.c
index 6f2b437dc..1b793c69c 100644
--- a/sys/src/cmd/cwfs/chk.c
+++ b/sys/src/cmd/cwfs/chk.c
@@ -59,7 +59,6 @@ static void *
 chkalloc(ulong n)
 {
 	char *p = mallocz(n, 1);
-
 	if (p == nil)
 		panic("chkalloc: out of memory");
 	return p;
diff --git a/sys/src/cmd/cwfs/config.c b/sys/src/cmd/cwfs/config.c
index bcb8b5e58..da71fcd69 100644
--- a/sys/src/cmd/cwfs/config.c
+++ b/sys/src/cmd/cwfs/config.c
@@ -175,7 +175,7 @@ config1(int c)
 	Device *d, *t;
 	int m;
 
-	d = malloc(sizeof(Device));
+	d = ialloc(sizeof(Device), 0);
 	do {
 		t = config();
 		if(d->cat.first == 0)
@@ -233,8 +233,7 @@ config(void)
 
 	if(f.error)
 		return devnone;
-	d = malloc(sizeof(Device));
-
+	d = ialloc(sizeof(Device), 0);
 	c = *f.charp++;
 	switch(c) {
 	default:
@@ -277,7 +276,7 @@ config(void)
 		d->wren.ctrl = -1;
 		d->wren.targ = -1;
 		d->wren.lun = -1;
-		d->wren.file = malloc((e - s) + 1);
+		d->wren.file = ialloc((e - s) + 1, 0);
 		memmove(d->wren.file, s, e - s);
 		d->wren.file[e - s] = 0;
 		break;
@@ -336,7 +335,7 @@ config(void)
 		d->type = Devcw;
 		d->cw.c = config();
 		d->cw.w = config();
-		d->cw.ro = malloc(sizeof(Device));
+		d->cw.ro = ialloc(sizeof(Device), 0);
 		d->cw.ro->type = Devro;
 		d->cw.ro->ro.parent = d;
 		f.lastcw = d;
diff --git a/sys/src/cmd/cwfs/cw.c b/sys/src/cmd/cwfs/cw.c
index dad3d5a38..d4a0b9dd0 100644
--- a/sys/src/cmd/cwfs/cw.c
+++ b/sys/src/cmd/cwfs/cw.c
@@ -400,7 +400,7 @@ cwinit1(Device *dev)
 		roflag = flag_install("ro", "-- ro reads and writes");
 		first = 1;
 	}
-	cw = malloc(sizeof(Cw));
+	cw = ialloc(sizeof(Cw), 0);
 	dev->private = cw;
 
 	cw->allflag = 0;
diff --git a/sys/src/cmd/cwfs/iobuf.c b/sys/src/cmd/cwfs/iobuf.c
index a48c7ace5..0caebf38b 100644
--- a/sys/src/cmd/cwfs/iobuf.c
+++ b/sys/src/cmd/cwfs/iobuf.c
@@ -1,7 +1,7 @@
 #include	"all.h"
 #include	"io.h"
 
-extern	long nhiob;
+extern	uint nhiob;
 extern	Hiob *hiob;
 
 Iobuf*
diff --git a/sys/src/cmd/cwfs/juke.c b/sys/src/cmd/cwfs/juke.c
index 25b916cfe..5deabd8a2 100644
--- a/sys/src/cmd/cwfs/juke.c
+++ b/sys/src/cmd/cwfs/juke.c
@@ -1166,7 +1166,7 @@ querychanger(Device *xdev)
 	 * allocate a juke structure
 	 * no locking problems.
 	 */
-	w = malloc(sizeof(Juke));
+	w = ialloc(sizeof(Juke), 0);
 	w->magic = Jukemagic;
 	w->isfixedsize = FIXEDSIZE;
 	w->link = jukelist;
diff --git a/sys/src/cmd/cwfs/main.c b/sys/src/cmd/cwfs/main.c
index 8f6f2a8e5..eaba6c1c1 100644
--- a/sys/src/cmd/cwfs/main.c
+++ b/sys/src/cmd/cwfs/main.c
@@ -71,7 +71,7 @@ mapinit(char *mapfile)
 				fields[0], mapfile);
 			continue;
 		}
-		map = malloc(sizeof *map);
+		map = ialloc(sizeof(Map), 0);
 		map->from = strdup(fields[0]);
 		map->to =   strdup(fields[1]);
 		map->fdev = iconfig(fields[0]);
@@ -323,15 +323,15 @@ main(int argc, char **argv)
 	netinit();
 	scsiinit();
 
-	files = malloc(conf.nfile * sizeof *files);
+	files = ialloc(conf.nfile * sizeof(*files), 0);
 	for(i=0; i < conf.nfile; i++) {
 		qlock(&files[i]);
 		qunlock(&files[i]);
 	}
 
-	wpaths = malloc(conf.nwpath * sizeof(*wpaths));
-	uid = malloc(conf.nuid * sizeof(*uid));
-	gidspace = malloc(conf.gidspace * sizeof(*gidspace));
+	wpaths = ialloc(conf.nwpath * sizeof(*wpaths), 0);
+	uid = ialloc(conf.nuid * sizeof(*uid), 0);
+	gidspace = ialloc(conf.gidspace * sizeof(*gidspace), 0);
 
 	iobufinit();
 
@@ -597,11 +597,12 @@ Devsize
 inqsize(char *file)
 {
 	int nf;
-	char *ln, *end, *data = malloc(strlen(file) + 5 + 1);
+	char *ln, *end, *data;
 	char *fields[4];
 	Devsize rv = -1;
 	Biobuf *bp;
 
+	data = malloc(strlen(file) + 5 + 1);
 	strcpy(data, file);
 	end = strstr(data, "/data");
 	if (end == nil)
@@ -621,4 +622,3 @@ inqsize(char *file)
 	free(data);
 	return rv;
 }
-
diff --git a/sys/src/cmd/cwfs/malloc.c b/sys/src/cmd/cwfs/malloc.c
index aed02b117..165599623 100644
--- a/sys/src/cmd/cwfs/malloc.c
+++ b/sys/src/cmd/cwfs/malloc.c
@@ -1,10 +1,12 @@
 #include "all.h"
 #include "io.h"
 
-static ulong
+#include <pool.h>
+
+static uvlong
 memsize(void)
 {
-	ulong pgsize, pgmax, userpgs, userused;
+	ulong pgsize, userpgs, userused;
 	char *s, *f[2];
 	int n, mpcnt;
 	Biobuf *bp;
@@ -37,17 +39,13 @@ memsize(void)
 		if(mpcnt < 1)
 			mpcnt = 1;
 		userpgs = (userpgs*mpcnt)/100;
-		pgmax = (1024*1024*1024)/pgsize;	/* 1GB max */
-		if(userpgs > pgmax)
-			userpgs = pgmax;
-		return userpgs*pgsize;
+		return (uvlong)userpgs*pgsize;
 	}
 	return 16*MB;
 }
 
-
-long	niob;
-long	nhiob;
+uint	niob;
+uint	nhiob;
 Hiob	*hiob;
 
 /*
@@ -56,14 +54,26 @@ Hiob	*hiob;
  * end of the allocated memory.
  */
 void*
-ialloc(ulong n, int align)
+ialloc(uintptr n, int align)
 {
-	void *p = mallocalign(n, align, 0, 0);
+	char *p;
+	int m;
 
-	if (p == nil)
+	if(align <= 0)
+		align = sizeof(uintptr);
+
+	mainmem->lock(mainmem);
+
+	p = sbrk(0);
+	if(m = n % align)
+		n += align - m;
+	if(m = (uintptr)p % align)
+		p += align - m;
+	if(brk(p+n) < 0)
 		panic("ialloc: out of memory");
-	setmalloctag(p, getcallerpc(&n));
-	memset(p, 0, n);
+
+	mainmem->unlock(mainmem);
+
 	return p;
 }
 
@@ -89,7 +99,7 @@ iobufinit(void)
 	while(!prime(nhiob))
 		nhiob++;
 	if(chatty)
-		print("\t%ld buffers; %ld hashes\n", niob, nhiob);
+		print("\t%ud buffers; %ud hashes\n", niob, nhiob);
 	hiob = ialloc(nhiob * sizeof(Hiob), 0);
 	hp = hiob;
 	for(i=0; i<nhiob; i++) {
diff --git a/sys/src/cmd/cwfs/mworm.c b/sys/src/cmd/cwfs/mworm.c
index 75159afc5..b4d444236 100644
--- a/sys/src/cmd/cwfs/mworm.c
+++ b/sys/src/cmd/cwfs/mworm.c
@@ -14,7 +14,7 @@ mcatinit(Device *d)
 		d->cat.ndev++;
 	}
 
-	list = malloc(d->cat.ndev*sizeof(Device*));
+	list = ialloc(d->cat.ndev * sizeof(Device*), 0);
 	d->private = list;
 	for(x=d->cat.first; x; x=x->link) {
 		*list++ = x;
diff --git a/sys/src/cmd/cwfs/portfns.h b/sys/src/cmd/cwfs/portfns.h
index eac4cafa0..ba584caf0 100644
--- a/sys/src/cmd/cwfs/portfns.h
+++ b/sys/src/cmd/cwfs/portfns.h
@@ -95,7 +95,7 @@ Chan*	getlcp(uchar*, long);
 Off	getraddr(Device*);
 void	hexdump(void*, int);
 int	iaccess(File*, Dentry*, int);
-void*	ialloc(ulong, int);
+void*	ialloc(uintptr, int);
 Off	ibbpow(int);
 Off	ibbpowsum(int);
 Device*	iconfig(char *);
diff --git a/sys/src/cmd/cwfs/scsi.c b/sys/src/cmd/cwfs/scsi.c
index 3e4c90d3b..6ce7a7cd9 100644
--- a/sys/src/cmd/cwfs/scsi.c
+++ b/sys/src/cmd/cwfs/scsi.c
@@ -46,8 +46,8 @@ scsiinit(void)
 
 			tp->ctlrno = ctlrno;
 			tp->targetno = targetno;
-			tp->inquiry = malloc(Ninquiry);
-			tp->sense = malloc(Nsense);
+			tp->inquiry = ialloc(Ninquiry, 0);
+			tp->sense = ialloc(Nsense, 0);
 		}
 	}
 }
diff --git a/sys/src/cmd/cwfs/sub.c b/sys/src/cmd/cwfs/sub.c
index 3f33310fa..c73c3d3ab 100644
--- a/sys/src/cmd/cwfs/sub.c
+++ b/sys/src/cmd/cwfs/sub.c
@@ -38,7 +38,7 @@ fs_chaninit(int count, int data)
 	Chan *cp, *icp;
 	int i;
 
-	p = malloc(count * (sizeof(Chan)+data));
+	p = ialloc(count * (sizeof(Chan)+data), 0);
 	icp = (Chan*)p;
 	for(i = 0; i < count; i++) {
 		cp = (Chan*)p;
@@ -761,17 +761,17 @@ mbinit(void)
 	msgalloc.lmsgbuf = 0;
 	msgalloc.smsgbuf = 0;
 	for(i=0; i<conf.nlgmsg; i++) {
-		mb = malloc(sizeof(Msgbuf));
+		mb = ialloc(sizeof(Msgbuf), 0);
 		mb->magic = Mbmagic;
-		mb->xdata = malloc(LARGEBUF+Slop);
+		mb->xdata = ialloc(LARGEBUF+Slop, 0);
 		mb->flags = LARGE;
 		mbfree(mb);
 		cons.nlarge++;
 	}
 	for(i=0; i<conf.nsmmsg; i++) {
-		mb = malloc(sizeof(Msgbuf));
+		mb = ialloc(sizeof(Msgbuf), 0);
 		mb->magic = Mbmagic;
-		mb->xdata = malloc(SMALLBUF+Slop);
+		mb->xdata = ialloc(SMALLBUF+Slop, 0);
 		mb->flags = 0;
 		mbfree(mb);
 		cons.nsmall++;
@@ -782,7 +782,7 @@ mbinit(void)
 	unlock(&rabuflock);
 	rabuffree = 0;
 	for(i=0; i<1000; i++) {
-		rb = malloc(sizeof(*rb));
+		rb = ialloc(sizeof(*rb), 0);
 		rb->link = rabuffree;
 		rabuffree = rb;
 	}
@@ -799,8 +799,8 @@ mballoc(int count, Chan *cp, int category)
 			panic("msgbuf count");
 		mb = msgalloc.lmsgbuf;
 		if(mb == nil) {
-			mb = malloc(sizeof(Msgbuf));
-			mb->xdata = malloc(LARGEBUF+Slop);
+			mb = ialloc(sizeof(Msgbuf), 0);
+			mb->xdata = ialloc(LARGEBUF+Slop, 0);
 			cons.nlarge++;
 		} else
 			msgalloc.lmsgbuf = mb->next;
@@ -808,8 +808,8 @@ mballoc(int count, Chan *cp, int category)
 	} else {
 		mb = msgalloc.smsgbuf;
 		if(mb == nil) {
-			mb = malloc(sizeof(Msgbuf));
-			mb->xdata = malloc(SMALLBUF+Slop);
+			mb = ialloc(sizeof(Msgbuf), 0);
+			mb->xdata = ialloc(SMALLBUF+Slop, 0);
 			cons.nsmall++;
 		} else
 			msgalloc.smsgbuf = mb->next;
@@ -958,7 +958,7 @@ newqueue(int size, char *name)
 {
 	Queue *q;
 
-	q = malloc(sizeof(Queue) + (size-1)*sizeof(void*));
+	q = ialloc(sizeof(Queue) + (size-1)*sizeof(void*), 0);
 	q->size = size;
 	q->avail = size;
 	q->count = 0;
diff --git a/sys/src/cmd/cwfs/wren.c b/sys/src/cmd/cwfs/wren.c
index 65338af8e..5f963a874 100644
--- a/sys/src/cmd/cwfs/wren.c
+++ b/sys/src/cmd/cwfs/wren.c
@@ -39,7 +39,7 @@ wreninit(Device *d)
 
 	if(d->private)
 		return;
-	d->private = dr = malloc(sizeof(Wren));
+	d->private = dr = ialloc(sizeof(Wren), 0);
 
 	if (d->wren.file)
 		d->wren.sddata = dataof(d->wren.file);