Commit 2fca5ccf authored by Jens Axboe's avatar Jens Axboe Committed by Linus Torvalds
Browse files

libata: switch to using block layer tagging support 



libata currently has a pretty dumb ATA_MAX_QUEUE loop for finding
a free tag to use. Instead of fixing that up, convert libata to
using block layer tagging - gets rid of code in libata, and is also
much faster.

Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
Acked-by: default avatarTejun Heo <tj@kernel.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 332edc2f

drivers/ata/libata-core.c

+6 −60
Original line number Diff line number Diff line
@@ -1713,8 +1713,6 @@ unsigned ata_exec_internal_sg(struct ata_device *dev, 
	else

		tag = 0;



	if (test_and_set_bit(tag, &ap->qc_allocated))

		BUG();

	qc = __ata_qc_from_tag(ap, tag);



	qc->tag = tag;
@@ -4552,37 +4550,6 @@ void swap_buf_le16(u16 *buf, unsigned int buf_words) 
#endif /* __BIG_ENDIAN */

}



/**

 *	ata_qc_new - Request an available ATA command, for queueing

 *	@ap: Port associated with device @dev

 *	@dev: Device from whom we request an available command structure

 *

 *	LOCKING:

 *	None.

 */



static struct ata_queued_cmd *ata_qc_new(struct ata_port *ap)

{

	struct ata_queued_cmd *qc = NULL;

	unsigned int i;



	/* no command while frozen */

	if (unlikely(ap->pflags & ATA_PFLAG_FROZEN))

		return NULL;



	/* the last tag is reserved for internal command. */

	for (i = 0; i < ATA_MAX_QUEUE - 1; i++)

		if (!test_and_set_bit(i, &ap->qc_allocated)) {

			qc = __ata_qc_from_tag(ap, i);

			break;

		}



	if (qc)

		qc->tag = i;



	return qc;

}



/**

 *	ata_qc_new_init - Request an available ATA command, and initialize it

 *	@dev: Device from whom we request an available command structure
@@ -4591,16 +4558,20 @@ static struct ata_queued_cmd *ata_qc_new(struct ata_port *ap) 
 *	None.

 */



struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev)

struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev, int tag)

{

	struct ata_port *ap = dev->link->ap;

	struct ata_queued_cmd *qc;



	qc = ata_qc_new(ap);

	if (unlikely(ap->pflags & ATA_PFLAG_FROZEN))

		return NULL;



	qc = __ata_qc_from_tag(ap, tag);

	if (qc) {

		qc->scsicmd = NULL;

		qc->ap = ap;

		qc->dev = dev;

		qc->tag = tag;



		ata_qc_reinit(qc);

	}
@@ -4608,31 +4579,6 @@ struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev) 
	return qc;

}



/**

 *	ata_qc_free - free unused ata_queued_cmd

 *	@qc: Command to complete

 *

 *	Designed to free unused ata_queued_cmd object

 *	in case something prevents using it.

 *

 *	LOCKING:

 *	spin_lock_irqsave(host lock)

 */

void ata_qc_free(struct ata_queued_cmd *qc)

{

	struct ata_port *ap = qc->ap;

	unsigned int tag;



	WARN_ON(qc == NULL);	/* ata_qc_from_tag _might_ return NULL */



	qc->flags = 0;

	tag = qc->tag;

	if (likely(ata_tag_valid(tag))) {

		qc->tag = ATA_TAG_POISON;

		clear_bit(tag, &ap->qc_allocated);

	}

}



void __ata_qc_complete(struct ata_queued_cmd *qc)

{

	struct ata_port *ap = qc->ap;

drivers/ata/libata-scsi.c

+8 −2
Original line number Diff line number Diff line
@@ -708,7 +708,7 @@ static struct ata_queued_cmd *ata_scsi_qc_new(struct ata_device *dev, 
{

	struct ata_queued_cmd *qc;



	qc = ata_qc_new_init(dev);

	qc = ata_qc_new_init(dev, cmd->request->tag);

	if (qc) {

		qc->scsicmd = cmd;

		qc->scsidone = done;
@@ -1103,7 +1103,8 @@ static int ata_scsi_dev_config(struct scsi_device *sdev, 


		depth = min(sdev->host->can_queue, ata_id_queue_depth(dev->id));

		depth = min(ATA_MAX_QUEUE - 1, depth);

		scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, depth);

		scsi_set_tag_type(sdev, MSG_SIMPLE_TAG);

		scsi_activate_tcq(sdev, depth);

	}



	return 0;
@@ -1943,6 +1944,11 @@ static unsigned int ata_scsiop_inq_std(struct ata_scsi_args *args, u8 *rbuf) 
		hdr[1] |= (1 << 7);



	memcpy(rbuf, hdr, sizeof(hdr));



	/* if ncq, set tags supported */

	if (ata_id_has_ncq(args->id))

		rbuf[7] |= (1 << 1);



	memcpy(&rbuf[8], "ATA     ", 8);

	ata_id_string(args->id, &rbuf[16], ATA_ID_PROD, 16);

	ata_id_string(args->id, &rbuf[32], ATA_ID_FW_REV, 4);

drivers/ata/libata.h

+17 −2
Original line number Diff line number Diff line
@@ -74,7 +74,7 @@ extern struct ata_link *ata_dev_phys_link(struct ata_device *dev); 
extern void ata_force_cbl(struct ata_port *ap);

extern u64 ata_tf_to_lba(const struct ata_taskfile *tf);

extern u64 ata_tf_to_lba48(const struct ata_taskfile *tf);

extern struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev);

extern struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev, int tag);

extern int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,

			   u64 block, u32 n_block, unsigned int tf_flags,

			   unsigned int tag);
@@ -103,7 +103,6 @@ extern int ata_dev_configure(struct ata_device *dev); 
extern int sata_down_spd_limit(struct ata_link *link);

extern int ata_down_xfermask_limit(struct ata_device *dev, unsigned int sel);

extern void ata_sg_clean(struct ata_queued_cmd *qc);

extern void ata_qc_free(struct ata_queued_cmd *qc);

extern void ata_qc_issue(struct ata_queued_cmd *qc);

extern void __ata_qc_complete(struct ata_queued_cmd *qc);

extern int atapi_check_dma(struct ata_queued_cmd *qc);
@@ -119,6 +118,22 @@ extern struct ata_port *ata_port_alloc(struct ata_host *host); 
extern void ata_dev_enable_pm(struct ata_device *dev, enum link_pm policy);

extern void ata_lpm_schedule(struct ata_port *ap, enum link_pm);



/**

 *	ata_qc_free - free unused ata_queued_cmd

 *	@qc: Command to complete

 *

 *	Designed to free unused ata_queued_cmd object

 *	in case something prevents using it.

 *

 *	LOCKING:

 *	spin_lock_irqsave(host lock)

 */

static inline void ata_qc_free(struct ata_queued_cmd *qc)

{

	qc->flags = 0;

	qc->tag = ATA_TAG_POISON;

}



/* libata-acpi.c */

#ifdef CONFIG_ATA_ACPI

extern void ata_acpi_associate_sata_port(struct ata_port *ap);

include/linux/libata.h

+0 −1
Original line number Diff line number Diff line
@@ -695,7 +695,6 @@ struct ata_port { 
	unsigned int		cbl;	/* cable type; ATA_CBL_xxx */



	struct ata_queued_cmd	qcmd[ATA_MAX_QUEUE];

	unsigned long		qc_allocated;

	unsigned int		qc_active;

	int			nr_active_links; /* #links with active qcs */

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