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devswap: dont assume Proc* structures returned from proctab() are continuous

--- a/sys/src/9/port/devswap.c

+++ b/sys/src/9/port/devswap.c

@@ -155,16 +155,14 @@

 static void

 pager(void*)

 {

-	int i;

+	Proc *p;

 	Segment *s;

-	Proc *p, *ep;

+	int x, i;

-	p = proctab(0);

-	ep = &p[conf.nproc];

-

 	while(waserror())

 		;

+	x = -1;

 	for(;;){

 		up->psstate = "Reclaim";

 		if(reclaim()){

@@ -185,11 +183,12 @@

 		i = ageclock;

 		do {

-			if(++p >= ep){

+			if(++x >= conf.nproc){

 				if(++ageclock == i)

 					goto Killbig;

-				p = proctab(0);

+				x = 0;

 			}

+			p = proctab(x);

 		} while(p->state == Dead || p->noswap || !canqlock(&p->seglock));

 		up->psstate = "Pageout";

 		for(i = 0; i < NSEG; i++) {

@@ -266,25 +265,24 @@

 static int

 canflush(Proc *p, Segment *s)

 {

-	int i;

-	Proc *ep;

+	int x, i;

 	if(incref(s) == 2)		/* Easy if we are the only user */

 		return canpage(p);

-	/* Now we must do hardwork to ensure all processes which have tlb

+	/*

+	 * Now we must do hardwork to ensure all processes which have tlb

 	 * entries for this segment will be flushed if we succeed in paging it out

 	 */

-	p = proctab(0);

-	ep = &p[conf.nproc];

-	while(p < ep) {

-		if(p->state != Dead) {

-			for(i = 0; i < NSEG; i++)

-				if(p->seg[i] == s)

-					if(!canpage(p))

-						return 0;

+	for(x = 0; x < conf.nproc; x++){

+		p = proctab(x);

+		if(p->state == Dead)

+			continue;

+		for(i = 0; i < NSEG; i++){

+			if(p->seg[i] == s)

+				if(!canpage(p))

+					return 0;

 		}

-		p++;

 	}

 	return 1;

 }

-- 

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