[PATCH v3 5/7] scsi: pm8001: Use sas_task_find_rq() for tagging

John Garry
2022-10-04T10:57:17Z

The request associated with a scsi command coming from the block layer
has a unique tag, so use that when possible for getting a CCB.

Unfortunately we don't support reserved commands in the SCSI midlayer yet,
so in the interim continue to manage those tags internally (along with
tags for private commands).

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Jack Wang <jinpu.wang@ionos.com>
---
drivers/scsi/pm8001/pm8001_init.c | 12 ++++--------
drivers/scsi/pm8001/pm8001_sas.c | 13 +++++++++----
drivers/scsi/pm8001/pm8001_sas.h | 11 ++++++++---
drivers/scsi/pm8001/pm80xx_hwi.c | 17 +++--------------
4 files changed, 24 insertions(+), 29 deletions(-)

diff --git a/drivers/scsi/pm8001/pm8001_init.c b/drivers/scsi/pm8001/pm8001_init.c
index 0edc9857a8bd..abb884ddcaf9 100644
--- a/drivers/scsi/pm8001/pm8001_init.c
+++ b/drivers/scsi/pm8001/pm8001_init.c
@@ -196,7 +196,7 @@ static void pm8001_free(struct pm8001_hba_info *pm8001_ha)
}
PM8001_CHIP_DISP->chip_iounmap(pm8001_ha);
flush_workqueue(pm8001_wq);
- bitmap_free(pm8001_ha->tags);
+ bitmap_free(pm8001_ha->rsvd_tags);
kfree(pm8001_ha);
}

@@ -1208,18 +1208,15 @@ static int pm8001_init_ccb_tag(struct pm8001_hba_info *pm8001_ha)
struct Scsi_Host *shost = pm8001_ha->shost;
struct device *dev = pm8001_ha->dev;
u32 max_out_io, ccb_count;
- u32 can_queue;
int i;

max_out_io = pm8001_ha->main_cfg_tbl.pm80xx_tbl.max_out_io;
ccb_count = min_t(int, PM8001_MAX_CCB, max_out_io);

- /* Update to the scsi host*/
- can_queue = ccb_count - PM8001_RESERVE_SLOT;
- shost->can_queue = can_queue;
+ shost->can_queue = ccb_count - PM8001_RESERVE_SLOT;

- pm8001_ha->tags = bitmap_zalloc(ccb_count, GFP_KERNEL);
- if (!pm8001_ha->tags)
+ pm8001_ha->rsvd_tags = bitmap_zalloc(PM8001_RESERVE_SLOT, GFP_KERNEL);
+ if (!pm8001_ha->rsvd_tags)
goto err_out;

/* Memory region for ccb_info*/
@@ -1244,7 +1241,6 @@ static int pm8001_init_ccb_tag(struct pm8001_hba_info *pm8001_ha)
pm8001_ha->ccb_info[i].task = NULL;
pm8001_ha->ccb_info[i].ccb_tag = PM8001_INVALID_TAG;
pm8001_ha->ccb_info[i].device = NULL;
- ++pm8001_ha->tags_num;
}

return 0;
diff --git a/drivers/scsi/pm8001/pm8001_sas.c b/drivers/scsi/pm8001/pm8001_sas.c
index 066dfa9f4683..f46588cd5c73 100644
--- a/drivers/scsi/pm8001/pm8001_sas.c
+++ b/drivers/scsi/pm8001/pm8001_sas.c
@@ -65,9 +65,12 @@ static int pm8001_find_tag(struct sas_task *task, u32 *tag)
*/
void pm8001_tag_free(struct pm8001_hba_info *pm8001_ha, u32 tag)
{
- void *bitmap = pm8001_ha->tags;
+ void *bitmap = pm8001_ha->rsvd_tags;
unsigned long flags;

+ if (tag >= PM8001_RESERVE_SLOT)
+ return;
+
spin_lock_irqsave(&pm8001_ha->bitmap_lock, flags);
__clear_bit(tag, bitmap);
spin_unlock_irqrestore(&pm8001_ha->bitmap_lock, flags);
@@ -80,18 +83,20 @@ void pm8001_tag_free(struct pm8001_hba_info *pm8001_ha, u32 tag)
*/
int pm8001_tag_alloc(struct pm8001_hba_info *pm8001_ha, u32 *tag_out)
{
- void *bitmap = pm8001_ha->tags;
+ void *bitmap = pm8001_ha->rsvd_tags;
unsigned long flags;
unsigned int tag;

spin_lock_irqsave(&pm8001_ha->bitmap_lock, flags);
- tag = find_first_zero_bit(bitmap, pm8001_ha->tags_num);
- if (tag >= pm8001_ha->tags_num) {
+ tag = find_first_zero_bit(bitmap, PM8001_RESERVE_SLOT);
+ if (tag >= PM8001_RESERVE_SLOT) {
spin_unlock_irqrestore(&pm8001_ha->bitmap_lock, flags);
return -SAS_QUEUE_FULL;
}
__set_bit(tag, bitmap);
spin_unlock_irqrestore(&pm8001_ha->bitmap_lock, flags);
+
+ /* reserved tags are in the lower region of the tagset */
*tag_out = tag;
return 0;
}
diff --git a/drivers/scsi/pm8001/pm8001_sas.h b/drivers/scsi/pm8001/pm8001_sas.h
index 9acaadf02150..b584e68664d8 100644
--- a/drivers/scsi/pm8001/pm8001_sas.h
+++ b/drivers/scsi/pm8001/pm8001_sas.h
@@ -510,8 +510,7 @@ struct pm8001_hba_info {
u32 chip_id;
const struct pm8001_chip_info *chip;
struct completion *nvmd_completion;
- int tags_num;
- unsigned long *tags;
+ unsigned long *rsvd_tags;
struct pm8001_phy phy[PM8001_MAX_PHYS];
struct pm8001_port port[PM8001_MAX_PHYS];
u32 id;
@@ -737,9 +736,15 @@ pm8001_ccb_alloc(struct pm8001_hba_info *pm8001_ha,
struct pm8001_device *dev, struct sas_task *task)
{
struct pm8001_ccb_info *ccb;
+ struct request *rq = NULL;
u32 tag;

- if (pm8001_tag_alloc(pm8001_ha, &tag)) {
+ if (task)
+ rq = sas_task_find_rq(task);
+
+ if (rq) {
+ tag = rq->tag + PM8001_RESERVE_SLOT;
+ } else if (pm8001_tag_alloc(pm8001_ha, &tag)) {
pm8001_dbg(pm8001_ha, FAIL, "Failed to allocate a tag\n");
return NULL;
}
diff --git a/drivers/scsi/pm8001/pm80xx_hwi.c b/drivers/scsi/pm8001/pm80xx_hwi.c
index 4484c498bcb6..ed2d65d3749a 100644
--- a/drivers/scsi/pm8001/pm80xx_hwi.c
+++ b/drivers/scsi/pm8001/pm80xx_hwi.c
@@ -4247,24 +4247,13 @@ static int check_enc_sat_cmd(struct sas_task *task)

static u32 pm80xx_chip_get_q_index(struct sas_task *task)
{
- struct scsi_cmnd *scmd = NULL;
+ struct request *rq = sas_task_find_rq(task);
u32 blk_tag;

- if (task->uldd_task) {
- struct ata_queued_cmd *qc;
-
- if (dev_is_sata(task->dev)) {
- qc = task->uldd_task;
- scmd = qc->scsicmd;
- } else {
- scmd = task->uldd_task;
- }
- }
-
- if (!scmd)
+ if (!rq)
return 0;

- blk_tag = blk_mq_unique_tag(scsi_cmd_to_rq(scmd));
+ blk_tag = blk_mq_unique_tag(rq);
return blk_mq_unique_tag_to_hwq(blk_tag);
}

--
2.25.1