Re: "sr: unaligned transfer" in 2.5.2-pre1

Peter Osterlund
2001-12-30T09:34:50Z

Greg KH <greg@kroah.com> writes:

> On Sun, Dec 23, 2001 at 06:44:43PM +0100, Peter Osterlund wrote:
> >
> > So, what changes are needed to make CD support work?
>
> The usb-storage driver needs some changes to get it to work properly in
> the 2.5.1 kernel due to the changes in the SCSI and bio layer. I've
> gotten a few other reports of problems, so you aren't alone :)
>
> As for when the changes will be done, any volunteers?

This patch seems to work for me. I hope it is correct. The ide-scsi
driver is basically doing the same thing already.

--- linux-2.5-packet/drivers/usb/storage/scsiglue.c.old Sun Dec 30 02:10:01 2001
+++ linux-2.5-packet/drivers/usb/storage/scsiglue.c Sun Dec 30 02:09:05 2001
@@ -145,9 +145,19 @@
static int queuecommand( Scsi_Cmnd *srb , void (*done)(Scsi_Cmnd *))
{
struct us_data *us = (struct us_data *)srb->host->hostdata[0];
+ struct scatterlist *sg;
+ int i;

US_DEBUGP("queuecommand() called\n");
srb->host_scribble = (unsigned char *)us;
+
+ /* Set up address field in the scatterlist. HighMem pages have
+ * already been bounced at this point. */
+ sg = (struct scatterlist *) srb->request_buffer;
+ for (i = 0; i < srb->use_sg; i++) {
+ BUG_ON(PageHighMem(sg[i].page));
+ sg[i].address = page_address(sg[i].page) + sg[i].offset;
+ }

/* get exclusive access to the structures we want */
down(&(us->queue_exclusion));

--
Peter Osterlund - petero2@telia.com