Commit 001102d7 authored by Tejun Heo's avatar Tejun Heo Committed by Jeff Garzik
Browse files

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: default avatarTejun Heo <htejun@gmail.com>
Cc: Rusty Russel <rusty@rustcorp.com.au>
Signed-off-by: default avatarJeff Garzik <jeff@garzik.org>
parent 55dba312

drivers/ata/libata-core.c

+15 −133
Original line number Diff line number Diff line
@@ -4478,9 +4478,6 @@ void ata_sg_clean(struct ata_queued_cmd *qc) 
	WARN_ON(!(qc->flags & ATA_QCFLAG_DMAMAP));

	WARN_ON(sg == NULL);



	if (qc->flags & ATA_QCFLAG_SINGLE)

		WARN_ON(qc->n_elem > 1);



	VPRINTK("unmapping %u sg elements\n", qc->n_elem);



	/* if we padded the buffer out to 32-bit bound, and data
@@ -4490,7 +4487,6 @@ void ata_sg_clean(struct ata_queued_cmd *qc) 
	if (qc->pad_len && !(qc->tf.flags & ATA_TFLAG_WRITE))

		pad_buf = ap->pad + (qc->tag * ATA_DMA_PAD_SZ);



	if (qc->flags & ATA_QCFLAG_SG) {

	if (qc->n_elem)

		dma_unmap_sg(ap->dev, sg, qc->n_elem, dir);

	/* restore last sg */
@@ -4501,17 +4497,6 @@ void ata_sg_clean(struct ata_queued_cmd *qc) 
		memcpy(addr + psg->offset, pad_buf, qc->pad_len);

		kunmap_atomic(addr, KM_IRQ0);

	}

	} else {

		if (qc->n_elem)

			dma_unmap_single(ap->dev,

				sg_dma_address(&sg[0]), sg_dma_len(&sg[0]),

				dir);

		/* restore sg */

		sg->length += qc->pad_len;

		if (pad_buf)

			memcpy(qc->buf_virt + sg->length - qc->pad_len,

			       pad_buf, qc->pad_len);

	}



	qc->flags &= ~ATA_QCFLAG_DMAMAP;

	qc->__sg = NULL;
@@ -4764,33 +4749,6 @@ void ata_dumb_qc_prep(struct ata_queued_cmd *qc) 


void ata_noop_qc_prep(struct ata_queued_cmd *qc) { }



/**

 *	ata_sg_init_one - Associate command with memory buffer

 *	@qc: Command to be associated

 *	@buf: Memory buffer

 *	@buflen: Length of memory buffer, in bytes.

 *

 *	Initialize the data-related elements of queued_cmd @qc

 *	to point to a single memory buffer, @buf of byte length @buflen.

 *

 *	LOCKING:

 *	spin_lock_irqsave(host lock)

 */



void ata_sg_init_one(struct ata_queued_cmd *qc, void *buf, unsigned int buflen)

{

	qc->flags |= ATA_QCFLAG_SINGLE;



	qc->__sg = &qc->sgent;

	qc->n_elem = 1;

	qc->orig_n_elem = 1;

	qc->buf_virt = buf;

	qc->nbytes = buflen;

	qc->cursg = qc->__sg;



	sg_init_one(&qc->sgent, buf, buflen);

}



/**

 *	ata_sg_init - Associate command with scatter-gather table.

 *	@qc: Command to be associated
@@ -4808,82 +4766,13 @@ void ata_sg_init_one(struct ata_queued_cmd *qc, void *buf, unsigned int buflen) 
void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,

		 unsigned int n_elem)

{

	qc->flags |= ATA_QCFLAG_SG;

	qc->flags |= ATA_QCFLAG_DMAMAP;

	qc->__sg = sg;

	qc->n_elem = n_elem;

	qc->orig_n_elem = n_elem;

	qc->cursg = qc->__sg;

}



/**

 *	ata_sg_setup_one - DMA-map the memory buffer associated with a command.

 *	@qc: Command with memory buffer to be mapped.

 *

 *	DMA-map the memory buffer associated with queued_cmd @qc.

 *

 *	LOCKING:

 *	spin_lock_irqsave(host lock)

 *

 *	RETURNS:

 *	Zero on success, negative on error.

 */



static int ata_sg_setup_one(struct ata_queued_cmd *qc)

{

	struct ata_port *ap = qc->ap;

	int dir = qc->dma_dir;

	struct scatterlist *sg = qc->__sg;

	dma_addr_t dma_address;

	int trim_sg = 0;



	/* we must lengthen transfers to end on a 32-bit boundary */

	qc->pad_len = sg->length & 3;

	if (qc->pad_len) {

		void *pad_buf = ap->pad + (qc->tag * ATA_DMA_PAD_SZ);

		struct scatterlist *psg = &qc->pad_sgent;



		WARN_ON(qc->dev->class != ATA_DEV_ATAPI);



		memset(pad_buf, 0, ATA_DMA_PAD_SZ);



		if (qc->tf.flags & ATA_TFLAG_WRITE)

			memcpy(pad_buf, qc->buf_virt + sg->length - qc->pad_len,

			       qc->pad_len);



		sg_dma_address(psg) = ap->pad_dma + (qc->tag * ATA_DMA_PAD_SZ);

		sg_dma_len(psg) = ATA_DMA_PAD_SZ;

		/* trim sg */

		sg->length -= qc->pad_len;

		if (sg->length == 0)

			trim_sg = 1;



		DPRINTK("padding done, sg->length=%u pad_len=%u\n",

			sg->length, qc->pad_len);

	}



	if (trim_sg) {

		qc->n_elem--;

		goto skip_map;

	}



	dma_address = dma_map_single(ap->dev, qc->buf_virt,

				     sg->length, dir);

	if (dma_mapping_error(dma_address)) {

		/* restore sg */

		sg->length += qc->pad_len;

		return -1;

	}



	sg_dma_address(sg) = dma_address;

	sg_dma_len(sg) = sg->length;



skip_map:

	DPRINTK("mapped buffer of %d bytes for %s\n", sg_dma_len(sg),

		qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read");



	return 0;

}



/**

 *	ata_sg_setup - DMA-map the scatter-gather table associated with a command.

 *	@qc: Command with scatter-gather table to be mapped.
@@ -4906,7 +4795,7 @@ static int ata_sg_setup(struct ata_queued_cmd *qc) 
	int n_elem, pre_n_elem, dir, trim_sg = 0;



	VPRINTK("ENTER, ata%u\n", ap->print_id);

	WARN_ON(!(qc->flags & ATA_QCFLAG_SG));

	WARN_ON(!(qc->flags & ATA_QCFLAG_DMAMAP));



	/* we must lengthen transfers to end on a 32-bit boundary */

	qc->pad_len = lsg->length & 3;
@@ -6025,16 +5914,10 @@ void ata_qc_issue(struct ata_queued_cmd *qc) 


	if (ata_is_dma(prot) || (ata_is_pio(prot) &&

				 (ap->flags & ATA_FLAG_PIO_DMA))) {

		if (qc->flags & ATA_QCFLAG_SG) {

		if (ata_sg_setup(qc))

			goto sg_err;

		} else if (qc->flags & ATA_QCFLAG_SINGLE) {

			if (ata_sg_setup_one(qc))

				goto sg_err;

		}

	} else {

		qc->flags &= ~ATA_QCFLAG_DMAMAP;

	}

	} else

		qc->flags &= ATA_QCFLAG_DMAMAP;



	/* if device is sleeping, schedule softreset and abort the link */

	if (unlikely(qc->dev->flags & ATA_DFLAG_SLEEPING)) {
@@ -7612,7 +7495,6 @@ EXPORT_SYMBOL_GPL(ata_host_register); 
EXPORT_SYMBOL_GPL(ata_host_activate);

EXPORT_SYMBOL_GPL(ata_host_detach);

EXPORT_SYMBOL_GPL(ata_sg_init);

EXPORT_SYMBOL_GPL(ata_sg_init_one);

EXPORT_SYMBOL_GPL(ata_hsm_move);

EXPORT_SYMBOL_GPL(ata_qc_complete);

EXPORT_SYMBOL_GPL(ata_qc_complete_multiple);

include/linux/libata.h

+1 −6
Original line number Diff line number Diff line
@@ -219,9 +219,7 @@ enum { 


	/* 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 ata_queued_cmd { 


	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_dumb_qc_prep(struct ata_queued_cmd *qc); 
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);

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