Commit 28361c40 authored by Jens Axboe's avatar Jens Axboe Committed by Tejun Heo
Browse files

libata: add extra internal command 



Bump the internal tag to 32, instead of stealing the last tag in
our regular command space. This works just fine, since we don't
actually need a separate hardware tag for this. Internal commands
cannot coexist with NCQ commands.

As a bonus, we get rid of the special casing of what tag to use
for the internal command.

This is in preparation for utilizing all 32 commands for normal IO.

Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent ba80c3a5

drivers/ata/libata-core.c

+6 −16
Original line number Diff line number Diff line
@@ -1570,7 +1570,7 @@ unsigned ata_exec_internal_sg(struct ata_device *dev, 
	u8 command = tf->command;

	int auto_timeout = 0;

	struct ata_queued_cmd *qc;

	unsigned int tag, preempted_tag;

	unsigned int preempted_tag;

	u32 preempted_sactive;

	u64 preempted_qc_active;

	int preempted_nr_active_links;
@@ -1588,20 +1588,10 @@ unsigned ata_exec_internal_sg(struct ata_device *dev, 
	}



	/* initialize internal qc */

	qc = __ata_qc_from_tag(ap, ATA_TAG_INTERNAL);



	/* XXX: Tag 0 is used for drivers with legacy EH as some

	 * drivers choke if any other tag is given.  This breaks

	 * ata_tag_internal() test for those drivers.  Don't use new

	 * EH stuff without converting to it.

	 */

	if (ap->ops->error_handler)

		tag = ATA_TAG_INTERNAL;

	else

		tag = 0;



	qc = __ata_qc_from_tag(ap, tag);



	qc->tag = qc->hw_tag = tag;

	qc->tag = ATA_TAG_INTERNAL;

	qc->hw_tag = 0;

	qc->scsicmd = NULL;

	qc->ap = ap;

	qc->dev = dev;
@@ -5156,7 +5146,7 @@ void ata_qc_free(struct ata_queued_cmd *qc) 


	qc->flags = 0;

	tag = qc->tag;

	if (likely(ata_tag_valid(tag))) {

	if (ata_tag_valid(tag)) {

		qc->tag = ATA_TAG_POISON;

		if (ap->flags & ATA_FLAG_SAS_HOST)

			ata_sas_free_tag(tag, ap);
@@ -5415,7 +5405,7 @@ void ata_qc_issue(struct ata_queued_cmd *qc) 
		WARN_ON_ONCE(link->sactive);



		ap->nr_active_links++;

		link->active_tag = qc->hw_tag;

		link->active_tag = qc->tag;

	}



	qc->flags |= ATA_QCFLAG_ACTIVE;

drivers/ata/libata-eh.c

+2 −1
Original line number Diff line number Diff line
@@ -1057,7 +1057,8 @@ static int ata_do_link_abort(struct ata_port *ap, struct ata_link *link) 
	/* we're gonna abort all commands, no need for fast drain */

	ata_eh_set_pending(ap, 0);



	for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {

	/* include internal tag in iteration */

	for (tag = 0; tag <= ATA_MAX_QUEUE; tag++) {

		struct ata_queued_cmd *qc = ata_qc_from_tag(ap, tag);



		if (qc && (!link || qc->dev->link == link)) {

include/linux/libata.h

+7 −8
Original line number Diff line number Diff line
@@ -125,9 +125,8 @@ enum { 
	LIBATA_MAX_PRD		= ATA_MAX_PRD / 2,

	LIBATA_DUMB_MAX_PRD	= ATA_MAX_PRD / 4,	/* Worst case */

	ATA_DEF_QUEUE		= 1,

	/* tag ATA_MAX_QUEUE - 1 is reserved for internal commands */

	ATA_MAX_QUEUE		= 32,

	ATA_TAG_INTERNAL	= ATA_MAX_QUEUE - 1,

	ATA_TAG_INTERNAL	= ATA_MAX_QUEUE,

	ATA_SHORT_PAUSE		= 16,



	ATAPI_MAX_DRAIN		= 16 << 10,
@@ -850,7 +849,7 @@ struct ata_port { 
	unsigned int		udma_mask;

	unsigned int		cbl;	/* cable type; ATA_CBL_xxx */



	struct ata_queued_cmd	qcmd[ATA_MAX_QUEUE];

	struct ata_queued_cmd	qcmd[ATA_MAX_QUEUE + 1];

	unsigned long		sas_tag_allocated; /* for sas tag allocation only */

	u64			qc_active;

	int			nr_active_links; /* #links with active qcs */
@@ -1486,14 +1485,14 @@ extern void ata_port_pbar_desc(struct ata_port *ap, int bar, ssize_t offset, 
			       const char *name);

#endif



static inline unsigned int ata_tag_valid(unsigned int tag)

static inline bool ata_tag_internal(unsigned int tag)

{

	return (tag < ATA_MAX_QUEUE) ? 1 : 0;

	return tag == ATA_TAG_INTERNAL;

}



static inline bool ata_tag_internal(unsigned int tag)

static inline bool ata_tag_valid(unsigned int tag)

{

	return tag == ATA_TAG_INTERNAL;

	return tag < ATA_MAX_QUEUE || ata_tag_internal(tag);

}



/*
@@ -1656,7 +1655,7 @@ static inline void ata_qc_set_polling(struct ata_queued_cmd *qc) 
static inline struct ata_queued_cmd *__ata_qc_from_tag(struct ata_port *ap,

						       unsigned int tag)

{

	if (likely(ata_tag_valid(tag)))

	if (ata_tag_valid(tag))

		return &ap->qcmd[tag];

	return NULL;

}

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