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: Jens Axboe
---
drivers/ata/libata-core.c | 66 ++++----------------------------------------
drivers/ata/libata-scsi.c | 10 +++++-
drivers/ata/libata.h | 19 +++++++++++-
include/linux/libata.h | 1 -
4 files changed, 31 insertions(+), 65 deletions(-)

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index c3c53e7..3d5da01 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -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;
@@ -4553,37 +4551,6 @@ void swap_buf_le16(u16 *buf, unsigned int buf_words)
}

/**
- * 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;
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 5d312dc..d5b9b72 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -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);
diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index fe2839e..d3831d3 100644
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -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);
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 947cf84..53ad28f 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -692,7 +692,6 @@ 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 */

--
1.6.0.2.588.g3102

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/