Commit 87260216 authored by Jens Axboe's avatar Jens Axboe
Browse files

libata: convert to using sg helpers 



This converts libata to using the sg helpers for looking up sg
elements, instead of doing it manually.

Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
parent a8474ce2

drivers/ata/libata-core.c

+16 −14
Original line number Diff line number Diff line
@@ -1410,7 +1410,7 @@ static void ata_qc_complete_internal(struct ata_queued_cmd *qc) 
 */

unsigned ata_exec_internal_sg(struct ata_device *dev,

			      struct ata_taskfile *tf, const u8 *cdb,

			      int dma_dir, struct scatterlist *sg,

			      int dma_dir, struct scatterlist *sgl,

			      unsigned int n_elem, unsigned long timeout)

{

	struct ata_link *link = dev->link;
@@ -1472,11 +1472,12 @@ unsigned ata_exec_internal_sg(struct ata_device *dev, 
	qc->dma_dir = dma_dir;

	if (dma_dir != DMA_NONE) {

		unsigned int i, buflen = 0;

		struct scatterlist *sg;



		for (i = 0; i < n_elem; i++)

			buflen += sg[i].length;

		for_each_sg(sgl, sg, n_elem, i)

			buflen += sg->length;



		ata_sg_init(qc, sg, n_elem);

		ata_sg_init(qc, sgl, n_elem);

		qc->nbytes = buflen;

	}
@@ -4292,7 +4293,7 @@ void ata_sg_clean(struct ata_queued_cmd *qc) 
		if (qc->n_elem)

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

		/* restore last sg */

		sg[qc->orig_n_elem - 1].length += qc->pad_len;

		sg_last(sg, qc->orig_n_elem)->length += qc->pad_len;

		if (pad_buf) {

			struct scatterlist *psg = &qc->pad_sgent;

			void *addr = kmap_atomic(psg->page, KM_IRQ0);
@@ -4547,6 +4548,7 @@ void ata_sg_init_one(struct ata_queued_cmd *qc, void *buf, unsigned int buflen) 
	qc->orig_n_elem = 1;

	qc->buf_virt = buf;

	qc->nbytes = buflen;

	qc->cursg = qc->__sg;



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

}
@@ -4572,6 +4574,7 @@ void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg, 
	qc->__sg = sg;

	qc->n_elem = n_elem;

	qc->orig_n_elem = n_elem;

	qc->cursg = qc->__sg;

}



/**
@@ -4661,7 +4664,7 @@ static int ata_sg_setup(struct ata_queued_cmd *qc) 
{

	struct ata_port *ap = qc->ap;

	struct scatterlist *sg = qc->__sg;

	struct scatterlist *lsg = &sg[qc->n_elem - 1];

	struct scatterlist *lsg = sg_last(qc->__sg, qc->n_elem);

	int n_elem, pre_n_elem, dir, trim_sg = 0;



	VPRINTK("ENTER, ata%u\n", ap->print_id);
@@ -4825,7 +4828,6 @@ void ata_data_xfer_noirq(struct ata_device *adev, unsigned char *buf, 
static void ata_pio_sector(struct ata_queued_cmd *qc)

{

	int do_write = (qc->tf.flags & ATA_TFLAG_WRITE);

	struct scatterlist *sg = qc->__sg;

	struct ata_port *ap = qc->ap;

	struct page *page;

	unsigned int offset;
@@ -4834,8 +4836,8 @@ static void ata_pio_sector(struct ata_queued_cmd *qc) 
	if (qc->curbytes == qc->nbytes - qc->sect_size)

		ap->hsm_task_state = HSM_ST_LAST;



	page = sg[qc->cursg].page;

	offset = sg[qc->cursg].offset + qc->cursg_ofs;

	page = qc->cursg->page;

	offset = qc->cursg->offset + qc->cursg_ofs;



	/* get the current page and offset */

	page = nth_page(page, (offset >> PAGE_SHIFT));
@@ -4863,8 +4865,8 @@ static void ata_pio_sector(struct ata_queued_cmd *qc) 
	qc->curbytes += qc->sect_size;

	qc->cursg_ofs += qc->sect_size;



	if (qc->cursg_ofs == (&sg[qc->cursg])->length) {

		qc->cursg++;

	if (qc->cursg_ofs == qc->cursg->length) {

		qc->cursg = sg_next(qc->cursg);

		qc->cursg_ofs = 0;

	}

}
@@ -4959,7 +4961,7 @@ static void __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes) 
		ap->hsm_task_state = HSM_ST_LAST;



next_sg:

	if (unlikely(qc->cursg >= qc->n_elem)) {

	if (unlikely(qc->cursg == sg_last(qc->__sg, qc->n_elem))) {

		/*

		 * The end of qc->sg is reached and the device expects

		 * more data to transfer. In order not to overrun qc->sg
@@ -4982,7 +4984,7 @@ static void __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes) 
		return;

	}



	sg = &qc->__sg[qc->cursg];

	sg = qc->cursg;



	page = sg->page;

	offset = sg->offset + qc->cursg_ofs;
@@ -5021,7 +5023,7 @@ static void __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes) 
	qc->cursg_ofs += count;



	if (qc->cursg_ofs == sg->length) {

		qc->cursg++;

		qc->cursg = sg_next(qc->cursg);

		qc->cursg_ofs = 0;

	}

include/linux/libata.h

+10 −6
Original line number Diff line number Diff line
@@ -29,7 +29,7 @@ 
#include <linux/delay.h>

#include <linux/interrupt.h>

#include <linux/dma-mapping.h>

#include <asm/scatterlist.h>

#include <linux/scatterlist.h>

#include <linux/io.h>

#include <linux/ata.h>

#include <linux/workqueue.h>
@@ -416,6 +416,7 @@ struct ata_queued_cmd { 
	unsigned long		flags;		/* ATA_QCFLAG_xxx */

	unsigned int		tag;

	unsigned int		n_elem;

	unsigned int		n_iter;

	unsigned int		orig_n_elem;



	int			dma_dir;
@@ -426,7 +427,7 @@ struct ata_queued_cmd { 
	unsigned int		nbytes;

	unsigned int		curbytes;



	unsigned int		cursg;

	struct scatterlist	*cursg;

	unsigned int		cursg_ofs;



	struct scatterlist	sgent;
@@ -1043,7 +1044,7 @@ ata_sg_is_last(struct scatterlist *sg, struct ata_queued_cmd *qc) 
		return 1;

	if (qc->pad_len)

		return 0;

	if (((sg - qc->__sg) + 1) == qc->n_elem)

	if (qc->n_iter == qc->n_elem)

		return 1;

	return 0;

}
@@ -1051,6 +1052,7 @@ ata_sg_is_last(struct scatterlist *sg, struct ata_queued_cmd *qc) 
static inline struct scatterlist *

ata_qc_first_sg(struct ata_queued_cmd *qc)

{

	qc->n_iter = 0;

	if (qc->n_elem)

		return qc->__sg;

	if (qc->pad_len)
@@ -1063,8 +1065,8 @@ ata_qc_next_sg(struct scatterlist *sg, struct ata_queued_cmd *qc) 
{

	if (sg == &qc->pad_sgent)

		return NULL;

	if (++sg - qc->__sg < qc->n_elem)

		return sg;

	if (++qc->n_iter < qc->n_elem)

		return sg_next(sg);

	if (qc->pad_len)

		return &qc->pad_sgent;

	return NULL;
@@ -1309,9 +1311,11 @@ static inline void ata_qc_reinit(struct ata_queued_cmd *qc) 
	qc->dma_dir = DMA_NONE;

	qc->__sg = NULL;

	qc->flags = 0;

	qc->cursg = qc->cursg_ofs = 0;

	qc->cursg = NULL;

	qc->cursg_ofs = 0;

	qc->nbytes = qc->curbytes = 0;

	qc->n_elem = 0;

	qc->n_iter = 0;

	qc->err_mask = 0;

	qc->pad_len = 0;

	qc->sect_size = ATA_SECT_SIZE;