From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@lst.de>
Subject: [PATCH] gdth: don't map zero-length requests
Date: Sun, 5 Feb 2006 16:36:23 +0100
Message-ID: <20060205153623.GA14143@lst.de>
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To: jejb@steeleye.com
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From: Jenx Axboe <axboe@suse.de>

Don't map zero-length requests in gdth, zome architectures don't like
that in their dma mapping routines.

[ I'm pretty sure Jens posted this before, but for some reason it got
  forgotten  --hch ]


Index: linux-2.6/drivers/scsi/gdth.c
===================================================================
--- linux-2.6.orig/drivers/scsi/gdth.c	2006-01-16 16:19:38.000000000 +0100
+++ linux-2.6/drivers/scsi/gdth.c	2006-02-05 16:34:12.000000000 +0100
@@ -2816,7 +2816,7 @@
             }
 #endif
 
-        } else {
+        } else if (scp->request_bufflen) {
             scp->SCp.Status = GDTH_MAP_SINGLE;
             scp->SCp.Message = (read_write == 1 ? 
                 PCI_DMA_TODEVICE : PCI_DMA_FROMDEVICE);