[SCSI] st: remove buf_to_sg

This removes unused buf_to_sg() that the non-dio path used.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: NKai Makisara <Kai.Makisara@kolumbus.fi>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

drivers/scsi/st.c

@@ -189,7 +189,6 @@ static void normalize_buffer(struct st_buffer *);
 static int append_to_buffer(const char __user *, struct st_buffer *, int);
 static int from_buffer(struct st_buffer *, char __user *, int);
 static void move_buffer_data(struct st_buffer *, int);
-static void buf_to_sg(struct st_buffer *, unsigned int);
 
 static int sgl_map_user_pages(struct st_buffer *, const unsigned int,
 			      unsigned long, size_t, int);
@@ -554,8 +553,6 @@ st_do_scsi(struct st_request * SRpnt, struct scsi_tape * STp, unsigned char *cmd
 		mdata->nr_entries = STp->buffer->sg_segs;
 		mdata->pages = STp->buffer->mapped_pages;
 	} else {
-		buf_to_sg(STp->buffer, bytes);
-
 		mdata->nr_entries =
 			DIV_ROUND_UP(bytes, PAGE_SIZE << mdata->page_order);
 		STp->buffer->map_data.pages = STp->buffer->reserved_pages;
@@ -3964,32 +3961,6 @@ static void move_buffer_data(struct st_buffer * st_bp, int offset)
 	}
 }
 
-
-/* Fill the s/g list up to the length required for this transfer */
-static void buf_to_sg(struct st_buffer *STbp, unsigned int length)
-{
-	int i;
-	unsigned int count;
-	struct scatterlist *sg;
-	struct st_buf_fragment *frp;
-
-	if (length == STbp->frp_sg_current)
-		return;   /* work already done */
-
-	sg = &(STbp->sg[0]);
-	frp = STbp->frp;
-	for (i=count=0; count < length; i++) {
-		if (length - count > frp[i].length)
-			sg_set_page(&sg[i], frp[i].page, frp[i].length, 0);
-		else
-			sg_set_page(&sg[i], frp[i].page, length - count, 0);
-		count += sg[i].length;
-	}
-	STbp->sg_segs = i;
-	STbp->frp_sg_current = length;
-}
-
-
 /* Validate the options from command line or module parameters */
 static void validate_options(void)
 {