[PATCH] dpt_i2o.c: fix transferred data length for scsi_set_resid()

[Miquel van Smoorenburg <mikevs@xs4all.net>]

This should go into 2.6.28 and -stable, I think.

dpt_i2o-fix-xferlen-for-scsi_set_resid.patch

[PATCH] dpt_i2o.c: fix transferred data length for scsi_set_resid()

dpt_i2o.c::adpt_i2o_to_scsi() reads the value at (reply+5) which
should contain the length in bytes of the transferred data. This
would be correct if reply was a u32 *. However it is a void * here,
so we need to read the value at (reply+20) instead.

The value at (reply+5) is usually 0xff0000, which is apparently
'large enough' and didn't cause any trouble until 2.6.27 where
427e59f09fdba387547106de7bab980b7fff77be caused this to become
visible through e.g. iostat -x .

Signed-off-by: Miquel van Smoorenburg <mikevs@xs4all.net>

--- linux-2.6.27.4/drivers/scsi/dpt_i2o.c.ORIG	2008-10-26 00:05:07.000000000 +0200
+++ linux-2.6.27.4/drivers/scsi/dpt_i2o.c	2008-11-04 23:43:13.000000000 +0100
@@ -2445,7 +2445,7 @@
 	hba_status = detailed_status >> 8;
 
 	// calculate resid for sg 
-	scsi_set_resid(cmd, scsi_bufflen(cmd) - readl(reply+5));
+	scsi_set_resid(cmd, scsi_bufflen(cmd) - readl(reply+20));
 
 	pHba = (adpt_hba*) cmd->device->host->hostdata[0];
 
@@ -2456,7 +2456,7 @@
 		case I2O_SCSI_DSC_SUCCESS:
 			cmd->result = (DID_OK << 16);
 			// handle underflow
-			if(readl(reply+5) < cmd->underflow ) {
+			if (readl(reply+20) < cmd->underflow) {
 				cmd->result = (DID_ERROR <<16);
 				printk(KERN_WARNING"%s: SCSI CMD underflow\n",pHba->name);
 			}