3 files changed, 45 insertions(+), 20 deletions(-)

M pc/devata.c
M port/qio.c
M port/sysfile.c

@@ 1825,7 1825,8 @@ atapiexec(Drive *dp)
 		nexterror();
 
 	if(cp->status & Serr){
-		DPRINT("%s: Bad packet command %ux, error %ux\n", dp->vol, cp->cmdblk[0], cp->error);
+		DPRINT("%s: Bad packet command 0x%ux, error 0x%ux\n",
+			dp->vol, cp->cmdblk[0], cp->error);
 		error(Eio);
 	}
 }


@@ 1985,7 1986,7 @@ atapipart(Drive *dp)
 	retrycount = 2;
 retry:
 	if(waserror()){
-		DPRINT("atapipart: cmd %uX error %uX\n", cp->cmdblk[0], cp->error);
+		DPRINT("atapipart: cmd 0x%uX error 0x%uX\n", cp->cmdblk[0], cp->error);
 		if((cp->status & Serr) && (cp->error & 0xF0) == 0x60){
 			dp->vers++;
 			if(retrycount){


@@ 2015,7 2016,7 @@ retry:
 	cp->cmdblk[4] = 18;
 	atapiexec(dp);
 	if(cp->count != 18){
-		print("cmd=%2.2uX, lastcmd=%2.2uX ", cp->cmd, cp->lastcmd);
+		print("cmd=0x%2.2uX, lastcmd=0x%2.2uX ", cp->cmd, cp->lastcmd);
 		print("cdsize count %d, status 0x%2.2uX, error 0x%2.2uX\n",
 			cp->count, cp->status, cp->error);
 		error(Eio);


@@ 2027,7 2028,7 @@ retry:
 	cp->cmdblk[0] = Ccapacity;
 	atapiexec(dp);
 	if(cp->count != 8){
-		print("cmd=%2.2uX, lastcmd=%2.2uX ", cp->cmd, cp->lastcmd);
+		print("cmd=0x%2.2uX, lastcmd=0x%2.2uX ", cp->cmd, cp->lastcmd);
 		print("cdsize count %d, status 0x%2.2uX, error 0x%2.2uX\n",
 			cp->count, cp->status, cp->error);
 		error(Eio);

@@ 35,7 35,8 @@ struct Queue
 	Block*	bfirst;		/* buffer */
 	Block*	blast;
 
-	int	len;		/* bytes in queue */
+	int	len;		/* bytes allocated to queue */
+	int	dlen;		/* data bytes in queue */
 	int	limit;		/* max bytes in queue */
 	int	inilim;		/* initial limit */
 	int	state;


@@ 531,6 532,7 @@ qget(Queue *q)
 	q->bfirst = b->next;
 	b->next = 0;
 	q->len -= BALLOC(b);
+	q->dlen -= BLEN(b);
 	QDEBUG checkb(b, "qget");
 
 	/* if writer flow controlled, restart */


@@ 568,10 570,12 @@ qdiscard(Queue *q, int len)
 			q->bfirst = b->next;
 			b->next = 0;
 			q->len -= BALLOC(b);
+			q->dlen -= BLEN(b);
 			freeb(b);
 		} else {
 			n = len - sofar;
 			b->rp += n;
+			q->dlen -= n;
 		}
 	}
 


@@ 625,6 629,7 @@ qconsume(Queue *q, void *vp, int len)
 	if((q->state & Qmsg) || len == n)
 		q->bfirst = b->next;
 	b->rp += len;
+	q->dlen -= len;
 
 	/* if writer flow controlled, restart */
 	if((q->state & Qflow) && q->len < q->limit/2){


@@ 643,6 648,7 @@ qconsume(Queue *q, void *vp, int len)
 	if((q->state & Qmsg) || len == n){
 		b->next = 0;
 		q->len -= BALLOC(b);
+		q->dlen -= BLEN(b);
 		freeb(b);
 	}
 	return len;


@@ 651,7 657,7 @@ qconsume(Queue *q, void *vp, int len)
 int
 qpass(Queue *q, Block *b)
 {
-	int len, dowakeup;
+	int dlen, len, dowakeup;
 
 	/* sync with qread */
 	dowakeup = 0;


@@ 668,14 674,17 @@ qpass(Queue *q, Block *b)
 	else
 		q->bfirst = b;
 	len = BALLOC(b);
+	dlen = BLEN(b);
 	QDEBUG checkb(b, "qpass");
 	while(b->next){
 		b = b->next;
 		QDEBUG checkb(b, "qpass");
 		len += BALLOC(b);
+		dlen += BLEN(b);
 	}
 	q->blast = b;
 	q->len += len;
+	q->dlen += dlen;
 
 	if(q->len >= q->limit/2)
 		q->state |= Qflow;


@@ 696,7 705,7 @@ checkqlen(q);
 int
 qpassnolim(Queue *q, Block *b)
 {
-	int len, dowakeup;
+	int dlen, len, dowakeup;
 
 	/* sync with qread */
 	dowakeup = 0;


@@ 708,14 717,17 @@ qpassnolim(Queue *q, Block *b)
 	else
 		q->bfirst = b;
 	len = BALLOC(b);
+	dlen = BLEN(b);
 	QDEBUG checkb(b, "qpass");
 	while(b->next){
 		b = b->next;
 		QDEBUG checkb(b, "qpass");
 		len += BALLOC(b);
+		dlen += BLEN(b);
 	}
 	q->blast = b;
 	q->len += len;
+	q->dlen += dlen;
 
 	if(q->len >= q->limit/2)
 		q->state |= Qflow;


@@ 792,6 804,7 @@ qproduce(Queue *q, void *vp, int len)
 	q->blast = b;
 	/* b->next = 0; done by iallocb() */
 	q->len += BALLOC(b);
+	q->dlen += BLEN(b);
 	QDEBUG checkb(b, "qproduce");
 
 	if(q->state & Qstarve){


@@ 935,6 948,7 @@ qbread(Queue *q, int len)
 	q->bfirst = b->next;
 	b->next = 0;
 	n = BLEN(b);
+	q->dlen -= n;
 	q->len -= BALLOC(b);
 	QDEBUG checkb(b, "qbread 1");
 


@@ 962,6 976,7 @@ qbread(Queue *q, int len)
 				q->blast = b;
 			q->bfirst = b;
 			q->len += BALLOC(b);
+			q->dlen += n;
 		}
 		nb->wp = nb->rp + len;
 	}


@@ 1018,7 1033,6 @@ qbwrite(Queue *q, Block *b)
 
 	dowakeup = 0;
 	n = BLEN(b);
-
 	qlock(&q->wlock);
 	if(waserror()){
 		qunlock(&q->wlock);


@@ 1058,6 1072,7 @@ qbwrite(Queue *q, Block *b)
 	q->blast = b;
 	b->next = 0;
 	q->len += BALLOC(b);
+	q->dlen += n;
 	QDEBUG checkb(b, "qbwrite");
 
 	if(q->state & Qstarve){


@@ 1147,6 1162,7 @@ qiwrite(Queue *q, void *vp, int len)
 			q->bfirst = b;
 		q->blast = b;
 		q->len += BALLOC(b);
+		q->dlen += n;
 
 		if(q->state & Qstarve){
 			q->state &= ~Qstarve;


@@ 1251,13 1267,7 @@ qreopen(Queue *q)
 int
 qlen(Queue *q)
 {
-	int len;
-	Block *b;
-
-	len = 0;
-	for(b = q->bfirst; b; b= b->next)
-		len += BLEN(b);
-	return len;
+	return q->dlen;
 }
 
 /*


@@ 1314,6 1324,7 @@ qflush(Queue *q)
 	bfirst = q->bfirst;
 	q->bfirst = 0;
 	q->len = 0;
+	q->dlen = 0;
 	iunlock(q);
 
 	/* free queued blocks */

@@ 378,14 378,15 @@ sysread(ulong *arg)
 	long n;
 	Chan *c;
 
-	validaddr(arg[1], arg[2], 1);
+	n = arg[2];
+	validaddr(arg[1], n, 1);
 	c = fdtochan(arg[0], OREAD, 1, 1);
+
 	if(waserror()) {
 		cclose(c);
 		nexterror();
 	}
 
-	n = arg[2];
 	dir = c->qid.path&CHDIR;
 
 	if(dir) {


@@ 443,24 444,36 @@ long
 syswrite(ulong *arg)
 {
 	Chan *c;
-	long n;
+	long m, n;
+	uvlong oo;
 
 	validaddr(arg[1], arg[2], 0);
+	n = arg[2];
 	c = fdtochan(arg[0], OWRITE, 1, 1);
 	if(waserror()) {
 		cclose(c);
+		lock(c);
+		c->offset -= n;
+		unlock(c);
 		nexterror();
 	}
 
 	if(c->qid.path & CHDIR)
 		error(Eisdir);
 
-	n = devtab[c->type]->write(c, (void*)arg[1], arg[2], c->offset);
-
 	lock(c);
+	oo = c->offset;
 	c->offset += n;
 	unlock(c);
 
+	m = devtab[c->type]->write(c, (void*)arg[1], n, oo);
+
+	if(m < n){
+		lock(c);
+		c->offset = oo + m;
+		unlock(c);
+	}
+
 	poperror();
 	cclose(c);