1 files changed, 9 insertions, 136 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index a109ccbda9ca..3587ac3fe3f3 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -4493,30 +4493,13 @@ void ata_sg_clean(struct ata_queued_cmd *qc)
 	struct ata_port *ap = qc->ap;
 	struct scatterlist *sg = qc->sg;
 	int dir = qc->dma_dir;
-	void *pad_buf = NULL;
 
 	WARN_ON(sg == NULL);
 
-	VPRINTK("unmapping %u sg elements\n", qc->mapped_n_elem);
+	VPRINTK("unmapping %u sg elements\n", qc->n_elem);
 
-	/* if we padded the buffer out to 32-bit bound, and data
-	 * xfer direction is from-device, we must copy from the
-	 * pad buffer back into the supplied buffer
-	 */
-	if (qc->pad_len && !(qc->tf.flags & ATA_TFLAG_WRITE))
-		pad_buf = ap->pad + (qc->tag * ATA_DMA_PAD_SZ);
-
-	if (qc->mapped_n_elem)
-		dma_unmap_sg(ap->dev, sg, qc->mapped_n_elem, dir);
-	/* restore last sg */
-	if (qc->last_sg)
-		*qc->last_sg = qc->saved_last_sg;
-	if (pad_buf) {
-		struct scatterlist *psg = &qc->extra_sg[1];
-		void *addr = kmap_atomic(sg_page(psg), KM_IRQ0);
-		memcpy(addr + psg->offset, pad_buf, qc->pad_len);
-		kunmap_atomic(addr, KM_IRQ0);
-	}
+	if (qc->n_elem)
+		dma_unmap_sg(ap->dev, sg, qc->n_elem, dir);
 
 	qc->flags &= ~ATA_QCFLAG_DMAMAP;
 	qc->sg = NULL;
@@ -4767,97 +4750,6 @@ void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
 	qc->cursg = qc->sg;
 }
 
-static unsigned int ata_sg_setup_extra(struct ata_queued_cmd *qc,
-				       unsigned int *n_elem_extra,
-				       unsigned int *nbytes_extra)
-{
-	struct ata_port *ap = qc->ap;
-	unsigned int n_elem = qc->n_elem;
-	struct scatterlist *lsg, *copy_lsg = NULL, *tsg = NULL, *esg = NULL;
-
-	*n_elem_extra = 0;
-	*nbytes_extra = 0;
-
-	/* needs padding? */
-	qc->pad_len = qc->nbytes & 3;
-
-	if (likely(!qc->pad_len))
-		return n_elem;
-
-	/* locate last sg and save it */
-	lsg = sg_last(qc->sg, n_elem);
-	qc->last_sg = lsg;
-	qc->saved_last_sg = *lsg;
-
-	sg_init_table(qc->extra_sg, ARRAY_SIZE(qc->extra_sg));
-
-	if (qc->pad_len) {
-		struct scatterlist *psg = &qc->extra_sg[1];
-		void *pad_buf = ap->pad + (qc->tag * ATA_DMA_PAD_SZ);
-		unsigned int offset;
-
-		WARN_ON(qc->dev->class != ATA_DEV_ATAPI);
-
-		memset(pad_buf, 0, ATA_DMA_PAD_SZ);
-
-		/* psg->page/offset are used to copy to-be-written
-		 * data in this function or read data in ata_sg_clean.
-		 */
-		offset = lsg->offset + lsg->length - qc->pad_len;
-		sg_set_page(psg, nth_page(sg_page(lsg), offset >> PAGE_SHIFT),
-			    qc->pad_len, offset_in_page(offset));
-
-		if (qc->tf.flags & ATA_TFLAG_WRITE) {
-			void *addr = kmap_atomic(sg_page(psg), KM_IRQ0);
-			memcpy(pad_buf, addr + psg->offset, qc->pad_len);
-			kunmap_atomic(addr, KM_IRQ0);
-		}
-
-		sg_dma_address(psg) = ap->pad_dma + (qc->tag * ATA_DMA_PAD_SZ);
-		sg_dma_len(psg) = ATA_DMA_PAD_SZ;
-
-		/* Trim the last sg entry and chain the original and
-		 * padding sg lists.
-		 *
-		 * Because chaining consumes one sg entry, one extra
-		 * sg entry is allocated and the last sg entry is
-		 * copied to it if the length isn't zero after padded
-		 * amount is removed.
-		 *
-		 * If the last sg entry is completely replaced by
-		 * padding sg entry, the first sg entry is skipped
-		 * while chaining.
-		 */
-		lsg->length -= qc->pad_len;
-		if (lsg->length) {
-			copy_lsg = &qc->extra_sg[0];
-			tsg = &qc->extra_sg[0];
-		} else {
-			n_elem--;
-			tsg = &qc->extra_sg[1];
-		}
-
-		esg = &qc->extra_sg[1];
-
-		(*n_elem_extra)++;
-		(*nbytes_extra) += 4 - qc->pad_len;
-	}
-
-	if (copy_lsg)
-		sg_set_page(copy_lsg, sg_page(lsg), lsg->length, lsg->offset);
-
-	sg_chain(lsg, 1, tsg);
-	sg_mark_end(esg);
-
-	/* sglist can't start with chaining sg entry, fast forward */
-	if (qc->sg == lsg) {
-		qc->sg = tsg;
-		qc->cursg = tsg;
-	}
-
-	return n_elem;
-}
-
 /**
  *	ata_sg_setup - DMA-map the scatter-gather table associated with a command.
  *	@qc: Command with scatter-gather table to be mapped.
@@ -4874,26 +4766,17 @@ static unsigned int ata_sg_setup_extra(struct ata_queued_cmd *qc,
 static int ata_sg_setup(struct ata_queued_cmd *qc)
 {
 	struct ata_port *ap = qc->ap;
-	unsigned int n_elem, n_elem_extra, nbytes_extra;
+	unsigned int n_elem;
 
 	VPRINTK("ENTER, ata%u\n", ap->print_id);
 
-	n_elem = ata_sg_setup_extra(qc, &n_elem_extra, &nbytes_extra);
+	n_elem = dma_map_sg(ap->dev, qc->sg, qc->n_elem, qc->dma_dir);
+	if (n_elem < 1)
+		return -1;
 
-	if (n_elem) {
-		n_elem = dma_map_sg(ap->dev, qc->sg, n_elem, qc->dma_dir);
-		if (n_elem < 1) {
-			/* restore last sg */
-			if (qc->last_sg)
-				*qc->last_sg = qc->saved_last_sg;
-			return -1;
-		}
-		DPRINTK("%d sg elements mapped\n", n_elem);
-	}
+	DPRINTK("%d sg elements mapped\n", n_elem);
 
-	qc->n_elem = qc->mapped_n_elem = n_elem;
-	qc->n_elem += n_elem_extra;
-	qc->nbytes += nbytes_extra;
+	qc->n_elem = n_elem;
 	qc->flags |= ATA_QCFLAG_DMAMAP;
 
 	return 0;
@@ -5962,9 +5845,6 @@ void ata_qc_issue(struct ata_queued_cmd *qc)
 	 */
 	BUG_ON(ata_is_data(prot) && (!qc->sg || !qc->n_elem || !qc->nbytes));
 
-	/* ata_sg_setup() may update nbytes */
-	qc->raw_nbytes = qc->nbytes;
-
 	if (ata_is_dma(prot) || (ata_is_pio(prot) &&
 				 (ap->flags & ATA_FLAG_PIO_DMA)))
 		if (ata_sg_setup(qc))
@@ -6573,19 +6453,12 @@ void ata_host_resume(struct ata_host *host)
 int ata_port_start(struct ata_port *ap)
 {
 	struct device *dev = ap->dev;
-	int rc;
 
 	ap->prd = dmam_alloc_coherent(dev, ATA_PRD_TBL_SZ, &ap->prd_dma,
 				      GFP_KERNEL);
 	if (!ap->prd)
 		return -ENOMEM;
 
-	rc = ata_pad_alloc(ap, dev);
-	if (rc)
-		return rc;
-
-	DPRINTK("prd alloc, virt %p, dma %llx\n", ap->prd,
-		(unsigned long long)ap->prd_dma);
 	return 0;
 }