libata: kill non-sg DMA interface

With atapi_request_sense() converted to use sg, there's no user of
non-sg interface.  Kill non-sg interface.

* ATA_QCFLAG_SINGLE and ATA_QCFLAG_SG are removed.  ATA_QCFLAG_DMAMAP
  is used instead.  (this way no LLD change is necessary)

* qc->buf_virt is removed.

* ata_sg_init_one() and ata_sg_setup_one() are removed.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Rusty Russel <rusty@rustcorp.com.au>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 7fa96cb..acd90ad 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -219,9 +219,7 @@
 
 	/* struct ata_queued_cmd flags */
 	ATA_QCFLAG_ACTIVE	= (1 << 0), /* cmd not yet ack'd to scsi lyer */
-	ATA_QCFLAG_SG		= (1 << 1), /* have s/g table? */
-	ATA_QCFLAG_SINGLE	= (1 << 2), /* no s/g, just a single buffer */
-	ATA_QCFLAG_DMAMAP	= ATA_QCFLAG_SG | ATA_QCFLAG_SINGLE,
+	ATA_QCFLAG_DMAMAP	= (1 << 1), /* SG table is DMA mapped */
 	ATA_QCFLAG_IO		= (1 << 3), /* standard IO command */
 	ATA_QCFLAG_RESULT_TF	= (1 << 4), /* result TF requested */
 	ATA_QCFLAG_CLEAR_EXCL	= (1 << 5), /* clear excl_link on completion */
@@ -475,7 +473,6 @@
 
 	struct scatterlist	sgent;
 	struct scatterlist	pad_sgent;
-	void			*buf_virt;
 
 	/* DO NOT iterate over __sg manually, use ata_for_each_sg() */
 	struct scatterlist	*__sg;
@@ -891,8 +888,6 @@
 extern void ata_qc_prep(struct ata_queued_cmd *qc);
 extern void ata_noop_qc_prep(struct ata_queued_cmd *qc);
 extern unsigned int ata_qc_issue_prot(struct ata_queued_cmd *qc);
-extern void ata_sg_init_one(struct ata_queued_cmd *qc, void *buf,
-		unsigned int buflen);
 extern void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
 		 unsigned int n_elem);
 extern unsigned int ata_dev_classify(const struct ata_taskfile *tf);