Re: cdrom: dropping to single frame dma

[Jens Axboe <axboe@suse.de>]

On Sun, Jul 25 2004, David Ford wrote:
> I've been trying to rip my CDs onto my HD, and last night after about 7 
> CDs I realized I was getting junk and it was taking forever to rip a 
> CD.  I'm using 2.6.8-rc2 and I have two different CD-ROMs in my 
> machine.  Both are burners.
> 
> I got a single "cdrom: dropping to single frame dma" message which 
> according to my research is part of the culprit.
> 
> See the thread on LKML back on 5/15/2004 titled "dma ripping", and again 
> on 6/15 titled "cdrom ripping / dropping to dingle frame dma" -- yes 
> that's a "d".
> 
> I'm guessing that Jens' patch for this didn't make it into the kernel.

Try this.

--- linux-2.6.8-rc2-mm1/drivers/cdrom/cdrom.c~	2004-08-02 14:56:48.259992912 +0200
+++ linux-2.6.8-rc2-mm1/drivers/cdrom/cdrom.c	2004-08-02 15:20:58.326549288 +0200
@@ -2004,6 +2004,8 @@
 	struct packet_command cgc;
 	int nr, ret;
 
+	cdi->last_sense = 0;
+
 	memset(&cgc, 0, sizeof(cgc));
 
 	/*
@@ -2055,6 +2057,8 @@
 	if (!q)
 		return -ENXIO;
 
+	cdi->last_sense = 0;
+
 	while (nframes) {
 		nr = nframes;
 		if (cdi->cdda_method == CDDA_BPC_SINGLE)
@@ -2102,6 +2106,7 @@
 
 		nframes -= nr;
 		lba += nr;
+		ubuf += len;
 	}
 
 	return ret;

-- 
Jens Axboe