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.
Greg, please apply.
Matt
Signed-off-by: Alan Stern <[EMAIL PROTECTED]>
Signed-off-by: Matthew Dharm <[EMAIL PROTECTED]>
Index: usb-2.6/drivers/usb/storage/usb.h
===================================================================
--- usb-2.6.orig/drivers/usb/storage/usb.h
+++ usb-2.6/drivers/usb/storage/usb.h
@@ -117,6 +117,7 @@ enum { US_DO_ALL_FLAGS };
*/
#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 us_data {
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;
Index: usb-2.6/drivers/usb/storage/transport.c
===================================================================
--- usb-2.6.orig/drivers/usb/storage/transport.c
+++ usb-2.6/drivers/usb/storage/transport.c
@@ -636,11 +636,11 @@ void usb_stor_invoke_transport(struct sc
/* use the new buffer we have */
old_request_buffer = srb->request_buffer;
- srb->request_buffer = srb->sense_buffer;
+ srb->request_buffer = us->sensebuf;
/* set the buffer length for transfer */
old_request_bufflen = srb->request_bufflen;
- srb->request_bufflen = 18;
+ srb->request_bufflen = US_SENSE_SIZE;
/* set up for no scatter-gather use */
old_sg = srb->use_sg;
@@ -652,6 +652,7 @@ void usb_stor_invoke_transport(struct sc
temp_result = us->transport(us->srb, us);
/* let's clean up right away */
+ memcpy(srb->sense_buffer, us->sensebuf, US_SENSE_SIZE);
srb->resid = old_resid;
srb->request_buffer = old_request_buffer;
srb->request_bufflen = old_request_bufflen;
Index: usb-2.6/drivers/usb/storage/usb.c
===================================================================
--- usb-2.6.orig/drivers/usb/storage/usb.c
+++ usb-2.6/drivers/usb/storage/usb.c
@@ -462,6 +462,12 @@ static int associate_dev(struct us_data
US_DEBUGP("I/O buffer allocation failed\n");
return -ENOMEM;
}
+
+ us->sensebuf = kmalloc(US_SENSE_SIZE, GFP_KERNEL);
+ if (!us->sensebuf) {
+ US_DEBUGP("Sense buffer allocation failed\n");
+ return -ENOMEM;
+ }
return 0;
}
@@ -807,6 +813,8 @@ static void dissociate_dev(struct us_dat
{
US_DEBUGP("-- %s\n", __FUNCTION__);
+ kfree(us->sensebuf);
+
/* Free the device-related DMA-mapped buffers */
if (us->cr)
usb_buffer_free(us->pusb_dev, sizeof(*us->cr), us->cr,
--
Matthew Dharm Home: [EMAIL PROTECTED]
Maintainer, Linux USB Mass Storage Driver
G: Money isn't everything, A.J.
AJ: Who convinced you of that?
G: The Chief, at my last salary review.
-- Mike and Greg
User Friendly, 11/3/1998
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