2022-03-15 22:43:20

by John Garry

[permalink] [raw]
Subject: [PATCH RFC 2/2] libata: Use scsi cmnd budget token for qc tag for SAS host

For attaining a qc tag for a SAS host we need to allocate a bit in
ata_port.sas_tag_allocated bitmap.

However we already have a unique tag per device in range
[0, ATA_MAX_QUEUE) in the scsi cmnd budget token, so just use that
instead.

Signed-off-by: John Garry <[email protected]>
---
drivers/ata/libata-core.c | 5 +++--
drivers/ata/libata-sata.c | 21 ++++-----------------
drivers/ata/libata-scsi.c | 2 +-
drivers/ata/libata.h | 4 ++--
include/linux/libata.h | 1 -
5 files changed, 10 insertions(+), 23 deletions(-)

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 0c854aebfe0b..2c0a550d3ecd 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -4572,8 +4572,9 @@ void swap_buf_le16(u16 *buf, unsigned int buf_words)
* None.
*/

-struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev, int tag)
+struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev, struct scsi_cmnd *scmd)
{
+ int tag = scsi_cmd_to_rq(scmd)->tag;
struct ata_port *ap = dev->link->ap;
struct ata_queued_cmd *qc;

@@ -4583,7 +4584,7 @@ struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev, int tag)

/* libsas case */
if (ap->flags & ATA_FLAG_SAS_HOST) {
- tag = ata_sas_allocate_tag(ap);
+ tag = ata_sas_allocate_tag(ap, scmd);
if (tag < 0)
return NULL;
}
diff --git a/drivers/ata/libata-sata.c b/drivers/ata/libata-sata.c
index 071158c0c44c..a4374fdffc43 100644
--- a/drivers/ata/libata-sata.c
+++ b/drivers/ata/libata-sata.c
@@ -1268,29 +1268,16 @@ int ata_sas_queuecmd(struct scsi_cmnd *cmd, struct ata_port *ap)
}
EXPORT_SYMBOL_GPL(ata_sas_queuecmd);

-int ata_sas_allocate_tag(struct ata_port *ap)
+int ata_sas_allocate_tag(struct ata_port *ap, struct scsi_cmnd *scmd)
{
- unsigned int max_queue = ap->host->n_tags;
- unsigned int i, tag;
+ if (scmd->budget_token >= ATA_MAX_QUEUE)
+ return -1;

- for (i = 0, tag = ap->sas_last_tag + 1; i < max_queue; i++, tag++) {
- tag = tag < max_queue ? tag : 0;
-
- /* the last tag is reserved for internal command. */
- if (ata_tag_internal(tag))
- continue;
-
- if (!test_and_set_bit(tag, &ap->sas_tag_allocated)) {
- ap->sas_last_tag = tag;
- return tag;
- }
- }
- return -1;
+ return scmd->budget_token;
}

void ata_sas_free_tag(unsigned int tag, struct ata_port *ap)
{
- clear_bit(tag, &ap->sas_tag_allocated);
}

/**
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index ed8be585a98f..45d63a2ba3ee 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -640,7 +640,7 @@ static struct ata_queued_cmd *ata_scsi_qc_new(struct ata_device *dev,
{
struct ata_queued_cmd *qc;

- qc = ata_qc_new_init(dev, scsi_cmd_to_rq(cmd)->tag);
+ qc = ata_qc_new_init(dev, cmd);
if (qc) {
qc->scsicmd = cmd;
qc->scsidone = scsi_done;
diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index 51e01acdd241..65302d7829fe 100644
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -44,7 +44,7 @@ static inline void ata_force_cbl(struct ata_port *ap) { }
#endif
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, int tag);
+extern struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev, struct scsi_cmnd *scmd);
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, int class);
@@ -93,7 +93,7 @@ extern unsigned int ata_read_log_page(struct ata_device *dev, u8 log,

/* libata-sata.c */
#ifdef CONFIG_SATA_HOST
-int ata_sas_allocate_tag(struct ata_port *ap);
+int ata_sas_allocate_tag(struct ata_port *ap, struct scsi_cmnd *scmd);
void ata_sas_free_tag(unsigned int tag, struct ata_port *ap);
#else
static inline int ata_sas_allocate_tag(struct ata_port *ap)
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 7f99b4d78822..3b9399f67b39 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -814,7 +814,6 @@ struct ata_port {
unsigned int cbl; /* cable type; ATA_CBL_xxx */

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 */
unsigned int sas_last_tag; /* track next tag hw expects */
--
2.26.2


2022-03-17 04:18:04

by Damien Le Moal

[permalink] [raw]
Subject: Re: [PATCH RFC 2/2] libata: Use scsi cmnd budget token for qc tag for SAS host

On 3/16/22 19:46, John Garry wrote:
> On 16/03/2022 08:34, Christoph Hellwig wrote:
>> In addition to the comments from Damien: I think we should kill
>> ata_qc_new_init as well. It is a bit pointless and having it in
>> libata-core.c when it pokes into scsi internals also doesn't make sense.
>>
>> So maybe something like:
>
> Seems reasonable to me at least.

Yep, that will be a nice cleanup.

>
> But I'd send these as 2x separate patches.
>
>> * sata_async_notification - SATA async notification handler
>> * @ap: ATA port where async notification is received
>> diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
>> index ed8be585a98f7c..5e0bc7b05a107e 100644
>> --- a/drivers/ata/libata-scsi.c
>> +++ b/drivers/ata/libata-scsi.c
>> @@ -638,24 +638,44 @@ EXPORT_SYMBOL_GPL(ata_scsi_ioctl);
>> static struct ata_queued_cmd *ata_scsi_qc_new(struct ata_device *dev,
>> struct scsi_cmnd *cmd)
>> {
> ...
>
>>
>> - if (scsi_cmd_to_rq(cmd)->rq_flags & RQF_QUIET)
>> - qc->flags |= ATA_QCFLAG_QUIET;
>> + if (ap->flags & ATA_FLAG_SAS_HOST) {
>> + /* XXX: add a comment here why SAS is different */
>
> I think this is simply because SAS hosts have shost.can_queue > 32
>
>> + if (WARN_ON_ONCE(cmd->budget_token >= ATA_MAX_QUEUE))
>> + goto fail;
>> + tag = cmd->budget_token;
>
> thanks,
> John


--
Damien Le Moal
Western Digital Research

2022-03-17 05:08:55

by John Garry

[permalink] [raw]
Subject: Re: [PATCH RFC 2/2] libata: Use scsi cmnd budget token for qc tag for SAS host

Hi Damien,

>> - }
>> - return -1;
>> + return scmd->budget_token;
>> }
> Since this is now not actually allocating a tag, I would rename this
> something like ata_sas_get_tag(). Or even better, simply open code this
> in ata_qc_new_init() since that is the only caller.

ok, I think it might be better to open code in ata_qc_new_init(), as
suggested. That should avoid the need for the return -1 call.

>
>>
>> void ata_sas_free_tag(unsigned int tag, struct ata_port *ap)
>> {
>> - clear_bit(tag, &ap->sas_tag_allocated);
>> }
> This is called only in ata_qc_free(). With this change, the function is
> empty, so let's completely remove it.
>

ok

>>
>> /**
>> diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
>> index ed8be585a98f..45d63a2ba3ee 100644
>> --- a/drivers/ata/libata-scsi.c
>> +++ b/drivers/ata/libata-scsi.c
>> @@ -640,7 +640,7 @@ static struct ata_queued_cmd *ata_scsi_qc_new(struct ata_device *dev,
>> {

Thanks,
John

2022-03-17 05:20:31

by Christoph Hellwig

[permalink] [raw]
Subject: Re: [PATCH RFC 2/2] libata: Use scsi cmnd budget token for qc tag for SAS host

In addition to the comments from Damien: I think we should kill
ata_qc_new_init as well. It is a bit pointless and having it in
libata-core.c when it pokes into scsi internals also doesn't make sense.

So maybe something like:

diff --git a/Documentation/driver-api/libata.rst b/Documentation/driver-api/libata.rst
index d477e296bda5f2..311af516a3fd9c 100644
--- a/Documentation/driver-api/libata.rst
+++ b/Documentation/driver-api/libata.rst
@@ -424,12 +424,6 @@ How commands are issued
-----------------------

Internal commands
- First, qc is allocated and initialized using :c:func:`ata_qc_new_init`.
- Although :c:func:`ata_qc_new_init` doesn't implement any wait or retry
- mechanism when qc is not available, internal commands are currently
- issued only during initialization and error recovery, so no other
- command is active and allocation is guaranteed to succeed.
-
Once allocated qc's taskfile is initialized for the command to be
executed. qc currently has two mechanisms to notify completion. One
is via ``qc->complete_fn()`` callback and the other is completion
@@ -447,11 +441,6 @@ SCSI commands
translated. No qc is involved in processing a simulated scmd. The
result is computed right away and the scmd is completed.

- For a translated scmd, :c:func:`ata_qc_new_init` is invoked to allocate a
- qc and the scmd is translated into the qc. SCSI midlayer's
- completion notification function pointer is stored into
- ``qc->scsidone``.
-
``qc->complete_fn()`` callback is used for completion notification. ATA
commands use :c:func:`ata_scsi_qc_complete` while ATAPI commands use
:c:func:`atapi_qc_complete`. Both functions end up calling ``qc->scsidone``
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 0c854aebfe0bdc..811fceb4e647fa 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -4563,42 +4563,6 @@ void swap_buf_le16(u16 *buf, unsigned int buf_words)
#endif /* __BIG_ENDIAN */
}

-/**
- * ata_qc_new_init - Request an available ATA command, and initialize it
- * @dev: Device from whom we request an available command structure
- * @tag: tag
- *
- * LOCKING:
- * None.
- */
-
-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;
-
- /* no command while frozen */
- if (unlikely(ap->pflags & ATA_PFLAG_FROZEN))
- return NULL;
-
- /* libsas case */
- if (ap->flags & ATA_FLAG_SAS_HOST) {
- tag = ata_sas_allocate_tag(ap);
- if (tag < 0)
- return NULL;
- }
-
- qc = __ata_qc_from_tag(ap, tag);
- qc->tag = qc->hw_tag = tag;
- qc->scsicmd = NULL;
- qc->ap = ap;
- qc->dev = dev;
-
- ata_qc_reinit(qc);
-
- return qc;
-}
-
/**
* ata_qc_free - free unused ata_queued_cmd
* @qc: Command to complete
@@ -4611,19 +4575,9 @@ struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev, int tag)
*/
void ata_qc_free(struct ata_queued_cmd *qc)
{
- struct ata_port *ap;
- unsigned int tag;
-
- WARN_ON_ONCE(qc == NULL); /* ata_qc_from_tag _might_ return NULL */
- ap = qc->ap;
-
qc->flags = 0;
- tag = qc->tag;
- if (ata_tag_valid(tag)) {
+ if (ata_tag_valid(qc->tag))
qc->tag = ATA_TAG_POISON;
- if (ap->flags & ATA_FLAG_SAS_HOST)
- ata_sas_free_tag(tag, ap);
- }
}

void __ata_qc_complete(struct ata_queued_cmd *qc)
diff --git a/drivers/ata/libata-sata.c b/drivers/ata/libata-sata.c
index 071158c0c44c1d..13e2c0d28b6937 100644
--- a/drivers/ata/libata-sata.c
+++ b/drivers/ata/libata-sata.c
@@ -1268,31 +1268,6 @@ int ata_sas_queuecmd(struct scsi_cmnd *cmd, struct ata_port *ap)
}
EXPORT_SYMBOL_GPL(ata_sas_queuecmd);

-int ata_sas_allocate_tag(struct ata_port *ap)
-{
- unsigned int max_queue = ap->host->n_tags;
- unsigned int i, tag;
-
- for (i = 0, tag = ap->sas_last_tag + 1; i < max_queue; i++, tag++) {
- tag = tag < max_queue ? tag : 0;
-
- /* the last tag is reserved for internal command. */
- if (ata_tag_internal(tag))
- continue;
-
- if (!test_and_set_bit(tag, &ap->sas_tag_allocated)) {
- ap->sas_last_tag = tag;
- return tag;
- }
- }
- return -1;
-}
-
-void ata_sas_free_tag(unsigned int tag, struct ata_port *ap)
-{
- clear_bit(tag, &ap->sas_tag_allocated);
-}
-
/**
* sata_async_notification - SATA async notification handler
* @ap: ATA port where async notification is received
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index ed8be585a98f7c..5e0bc7b05a107e 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -638,24 +638,44 @@ EXPORT_SYMBOL_GPL(ata_scsi_ioctl);
static struct ata_queued_cmd *ata_scsi_qc_new(struct ata_device *dev,
struct scsi_cmnd *cmd)
{
+ struct ata_port *ap = dev->link->ap;
struct ata_queued_cmd *qc;
+ int tag;

- qc = ata_qc_new_init(dev, scsi_cmd_to_rq(cmd)->tag);
- if (qc) {
- qc->scsicmd = cmd;
- qc->scsidone = scsi_done;
-
- qc->sg = scsi_sglist(cmd);
- qc->n_elem = scsi_sg_count(cmd);
+ if (unlikely(ap->pflags & ATA_PFLAG_FROZEN))
+ goto fail;

- if (scsi_cmd_to_rq(cmd)->rq_flags & RQF_QUIET)
- qc->flags |= ATA_QCFLAG_QUIET;
+ if (ap->flags & ATA_FLAG_SAS_HOST) {
+ /* XXX: add a comment here why SAS is different */
+ if (WARN_ON_ONCE(cmd->budget_token >= ATA_MAX_QUEUE))
+ goto fail;
+ tag = cmd->budget_token;
} else {
- cmd->result = (DID_OK << 16) | SAM_STAT_TASK_SET_FULL;
- scsi_done(cmd);
+ tag = scsi_cmd_to_rq(cmd)->tag;
}

+ qc = __ata_qc_from_tag(ap, tag);
+ qc->tag = qc->hw_tag = tag;
+ qc->scsicmd = NULL;
+ qc->ap = ap;
+ qc->dev = dev;
+
+ ata_qc_reinit(qc);
+
+ qc->scsicmd = cmd;
+ qc->scsidone = scsi_done;
+
+ qc->sg = scsi_sglist(cmd);
+ qc->n_elem = scsi_sg_count(cmd);
+
+ if (scsi_cmd_to_rq(cmd)->rq_flags & RQF_QUIET)
+ qc->flags |= ATA_QCFLAG_QUIET;
return qc;
+
+fail:
+ cmd->result = (DID_OK << 16) | SAM_STAT_TASK_SET_FULL;
+ scsi_done(cmd);
+ return NULL;
}

static void ata_qc_set_pc_nbytes(struct ata_queued_cmd *qc)
diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index 51e01acdd24107..191f8bfe038656 100644
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -44,7 +44,6 @@ static inline void ata_force_cbl(struct ata_port *ap) { }
#endif
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, 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, int class);
@@ -91,18 +90,6 @@ extern unsigned int ata_read_log_page(struct ata_device *dev, u8 log,

#define to_ata_port(d) container_of(d, struct ata_port, tdev)

-/* libata-sata.c */
-#ifdef CONFIG_SATA_HOST
-int ata_sas_allocate_tag(struct ata_port *ap);
-void ata_sas_free_tag(unsigned int tag, struct ata_port *ap);
-#else
-static inline int ata_sas_allocate_tag(struct ata_port *ap)
-{
- return -EOPNOTSUPP;
-}
-static inline void ata_sas_free_tag(unsigned int tag, struct ata_port *ap) { }
-#endif
-
/* libata-acpi.c */
#ifdef CONFIG_ATA_ACPI
extern unsigned int ata_acpi_gtf_filter;
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 7f99b4d788223b..3b9399f67b3902 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -814,7 +814,6 @@ struct ata_port {
unsigned int cbl; /* cable type; ATA_CBL_xxx */

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 */
unsigned int sas_last_tag; /* track next tag hw expects */

2022-03-17 06:15:02

by John Garry

[permalink] [raw]
Subject: Re: [PATCH RFC 2/2] libata: Use scsi cmnd budget token for qc tag for SAS host

On 16/03/2022 08:34, Christoph Hellwig wrote:
> In addition to the comments from Damien: I think we should kill
> ata_qc_new_init as well. It is a bit pointless and having it in
> libata-core.c when it pokes into scsi internals also doesn't make sense.
>
> So maybe something like:

Seems reasonable to me at least.

But I'd send these as 2x separate patches.

> * sata_async_notification - SATA async notification handler
> * @ap: ATA port where async notification is received
> diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
> index ed8be585a98f7c..5e0bc7b05a107e 100644
> --- a/drivers/ata/libata-scsi.c
> +++ b/drivers/ata/libata-scsi.c
> @@ -638,24 +638,44 @@ EXPORT_SYMBOL_GPL(ata_scsi_ioctl);
> static struct ata_queued_cmd *ata_scsi_qc_new(struct ata_device *dev,
> struct scsi_cmnd *cmd)
> {
...

>
> - if (scsi_cmd_to_rq(cmd)->rq_flags & RQF_QUIET)
> - qc->flags |= ATA_QCFLAG_QUIET;
> + if (ap->flags & ATA_FLAG_SAS_HOST) {
> + /* XXX: add a comment here why SAS is different */

I think this is simply because SAS hosts have shost.can_queue > 32

> + if (WARN_ON_ONCE(cmd->budget_token >= ATA_MAX_QUEUE))
> + goto fail;
> + tag = cmd->budget_token;

thanks,
John

2022-03-17 06:27:19

by Damien Le Moal

[permalink] [raw]
Subject: Re: [PATCH RFC 2/2] libata: Use scsi cmnd budget token for qc tag for SAS host

On 3/15/22 19:39, John Garry wrote:
> For attaining a qc tag for a SAS host we need to allocate a bit in
> ata_port.sas_tag_allocated bitmap.
>
> However we already have a unique tag per device in range
> [0, ATA_MAX_QUEUE) in the scsi cmnd budget token, so just use that
> instead.
>
> Signed-off-by: John Garry <[email protected]>
> ---
> drivers/ata/libata-core.c | 5 +++--
> drivers/ata/libata-sata.c | 21 ++++-----------------
> drivers/ata/libata-scsi.c | 2 +-
> drivers/ata/libata.h | 4 ++--
> include/linux/libata.h | 1 -
> 5 files changed, 10 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
> index 0c854aebfe0b..2c0a550d3ecd 100644
> --- a/drivers/ata/libata-core.c
> +++ b/drivers/ata/libata-core.c
> @@ -4572,8 +4572,9 @@ void swap_buf_le16(u16 *buf, unsigned int buf_words)
> * None.
> */
>
> -struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev, int tag)
> +struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev, struct scsi_cmnd *scmd)
> {
> + int tag = scsi_cmd_to_rq(scmd)->tag;
> struct ata_port *ap = dev->link->ap;
> struct ata_queued_cmd *qc;
>
> @@ -4583,7 +4584,7 @@ struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev, int tag)
>
> /* libsas case */
> if (ap->flags & ATA_FLAG_SAS_HOST) {
> - tag = ata_sas_allocate_tag(ap);
> + tag = ata_sas_allocate_tag(ap, scmd);
> if (tag < 0)
> return NULL;
> }
> diff --git a/drivers/ata/libata-sata.c b/drivers/ata/libata-sata.c
> index 071158c0c44c..a4374fdffc43 100644
> --- a/drivers/ata/libata-sata.c
> +++ b/drivers/ata/libata-sata.c
> @@ -1268,29 +1268,16 @@ int ata_sas_queuecmd(struct scsi_cmnd *cmd, struct ata_port *ap)
> }
> EXPORT_SYMBOL_GPL(ata_sas_queuecmd);
>
> -int ata_sas_allocate_tag(struct ata_port *ap)
> +int ata_sas_allocate_tag(struct ata_port *ap, struct scsi_cmnd *scmd)
> {
> - unsigned int max_queue = ap->host->n_tags;
> - unsigned int i, tag;
> + if (scmd->budget_token >= ATA_MAX_QUEUE)
> + return -1;
>
> - for (i = 0, tag = ap->sas_last_tag + 1; i < max_queue; i++, tag++) {
> - tag = tag < max_queue ? tag : 0;
> -
> - /* the last tag is reserved for internal command. */
> - if (ata_tag_internal(tag))
> - continue;
> -
> - if (!test_and_set_bit(tag, &ap->sas_tag_allocated)) {
> - ap->sas_last_tag = tag;
> - return tag;
> - }
> - }
> - return -1;
> + return scmd->budget_token;
> }

Since this is now not actually allocating a tag, I would rename this
something like ata_sas_get_tag(). Or even better, simply open code this
in ata_qc_new_init() since that is the only caller.

>
> void ata_sas_free_tag(unsigned int tag, struct ata_port *ap)
> {
> - clear_bit(tag, &ap->sas_tag_allocated);
> }

This is called only in ata_qc_free(). With this change, the function is
empty, so let's completely remove it.

>
> /**
> diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
> index ed8be585a98f..45d63a2ba3ee 100644
> --- a/drivers/ata/libata-scsi.c
> +++ b/drivers/ata/libata-scsi.c
> @@ -640,7 +640,7 @@ static struct ata_queued_cmd *ata_scsi_qc_new(struct ata_device *dev,
> {
> struct ata_queued_cmd *qc;
>
> - qc = ata_qc_new_init(dev, scsi_cmd_to_rq(cmd)->tag);
> + qc = ata_qc_new_init(dev, cmd);
> if (qc) {
> qc->scsicmd = cmd;
> qc->scsidone = scsi_done;
> diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
> index 51e01acdd241..65302d7829fe 100644
> --- a/drivers/ata/libata.h
> +++ b/drivers/ata/libata.h
> @@ -44,7 +44,7 @@ static inline void ata_force_cbl(struct ata_port *ap) { }
> #endif
> 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, int tag);
> +extern struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev, struct scsi_cmnd *scmd);
> 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, int class);
> @@ -93,7 +93,7 @@ extern unsigned int ata_read_log_page(struct ata_device *dev, u8 log,
>
> /* libata-sata.c */
> #ifdef CONFIG_SATA_HOST
> -int ata_sas_allocate_tag(struct ata_port *ap);
> +int ata_sas_allocate_tag(struct ata_port *ap, struct scsi_cmnd *scmd);
> void ata_sas_free_tag(unsigned int tag, struct ata_port *ap);
> #else
> static inline int ata_sas_allocate_tag(struct ata_port *ap)
> diff --git a/include/linux/libata.h b/include/linux/libata.h
> index 7f99b4d78822..3b9399f67b39 100644
> --- a/include/linux/libata.h
> +++ b/include/linux/libata.h
> @@ -814,7 +814,6 @@ struct ata_port {
> unsigned int cbl; /* cable type; ATA_CBL_xxx */
>
> 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 */
> unsigned int sas_last_tag; /* track next tag hw expects */


--
Damien Le Moal
Western Digital Research