[PATCH] PATCH: usb-storage: allocate separate sense buffer

This patch is from Alan Stern (as560).  It has been rediffed against a
current tree.

This patch allocates a separate buffer for usb-storage to use when
auto-sensing.  Up to now we have been using the sense buffer embedded in a
scsi_cmnd struct, which is dangerous on hosts that (a) don't do
cache-coherent DMA or (b) have DMA alignment restrictions.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/storage/usb.h b/drivers/usb/storage/usb.h
index a195ada..dfa4dc7 100644
--- a/drivers/usb/storage/usb.h
+++ b/drivers/usb/storage/usb.h
@@ -117,6 +117,7 @@
  */
 
 #define US_IOBUF_SIZE		64	/* Size of the DMA-mapped I/O buffer */
+#define US_SENSE_SIZE		18	/* Size of the autosense data buffer */
 
 typedef int (*trans_cmnd)(struct scsi_cmnd *, struct us_data*);
 typedef int (*trans_reset)(struct us_data*);
@@ -168,6 +169,7 @@
 	struct usb_ctrlrequest	*cr;		 /* control requests	 */
 	struct usb_sg_request	current_sg;	 /* scatter-gather req.  */
 	unsigned char		*iobuf;		 /* I/O buffer		 */
+	unsigned char		*sensebuf;	 /* sense data buffer	 */
 	dma_addr_t		cr_dma;		 /* buffer DMA addresses */
 	dma_addr_t		iobuf_dma;