[PATCH RFC v2 10/18] libata/scsi: libsas: Add sas_queuecommand_internal()

[John Garry <john.garry@huawei.com>]

Add a callback for sht reserved_queuecommand callback. We need to add
libata helper ata_is_scmd_ata_internal() as it is difficult to know
whether the request should be queued as an ATA internal command.

We will store the sas_task in the scsi_cmnd payload also in future.

Signed-off-by: John Garry <john.garry@huawei.com>
---
 drivers/ata/libata-core.c           |  8 ++++++++
 drivers/scsi/libsas/sas_scsi_host.c | 21 +++++++++++++++++++++
 include/linux/libata.h              |  1 +
 include/scsi/libsas.h               |  8 ++++++++
 4 files changed, 38 insertions(+)

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 6b1aaeccb253..a9645951a0f0 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -1454,6 +1454,14 @@ static void ata_internal_end_rq(struct request *rq, blk_status_t error)
 	complete(waiting);
 }
 
+bool ata_is_scmd_ata_internal(struct scsi_cmnd *scmd)
+{
+	struct request *rq = scsi_cmd_to_rq(scmd);
+
+	return rq->end_io == ata_internal_end_rq;
+}
+EXPORT_SYMBOL_GPL(ata_is_scmd_ata_internal);
+
 /**
  *	ata_exec_internal_sg - execute libata internal command
  *	@dev: Device to which the command is sent
diff --git a/drivers/scsi/libsas/sas_scsi_host.c b/drivers/scsi/libsas/sas_scsi_host.c
index 9c82e5dc4fcc..42279a6d6b06 100644
--- a/drivers/scsi/libsas/sas_scsi_host.c
+++ b/drivers/scsi/libsas/sas_scsi_host.c
@@ -158,6 +158,27 @@ static struct sas_task *sas_create_task(struct scsi_cmnd *cmd,
 	return task;
 }
 
+int sas_queuecommand_internal(struct Scsi_Host *shost, struct scsi_cmnd *cmnd)
+{
+	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
+	struct sas_internal *i = to_sas_internal(ha->core.shost->transportt);
+	struct request *rq = scsi_cmd_to_rq(cmnd);
+
+	if (ata_is_scmd_ata_internal(cmnd)) {
+		struct ata_queued_cmd *qc = (struct ata_queued_cmd *)cmnd->host_scribble;
+		struct ata_port *ap = qc->ap;
+		int res;
+
+		spin_lock_irq(ap->lock);
+		res = ata_sas_queuecmd(cmnd, ap);
+		spin_unlock_irq(ap->lock);
+		return res;
+	}
+
+	return i->dft->lldd_execute_task(sas_rq_to_task(rq), GFP_KERNEL);
+}
+EXPORT_SYMBOL_GPL(sas_queuecommand_internal);
+
 int sas_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
 {
 	struct sas_internal *i = to_sas_internal(host->transportt);
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 5fa6f56bba81..6cb7a5bcb308 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -1238,6 +1238,7 @@ extern int ata_sas_slave_configure(struct scsi_device *, struct ata_port *);
 extern int ata_sas_queuecmd(struct scsi_cmnd *cmd, struct ata_port *ap);
 extern void ata_tf_to_fis(const struct ata_taskfile *tf,
 			  u8 pmp, int is_cmd, u8 *fis);
+extern bool ata_is_scmd_ata_internal(struct scsi_cmnd *scmd);
 extern void ata_tf_from_fis(const u8 *fis, struct ata_taskfile *tf);
 extern int ata_qc_complete_multiple(struct ata_port *ap, u64 qc_active);
 extern bool sata_lpm_ignore_phy_events(struct ata_link *link);
diff --git a/include/scsi/libsas.h b/include/scsi/libsas.h
index ff04eb6d250b..261169ffdca6 100644
--- a/include/scsi/libsas.h
+++ b/include/scsi/libsas.h
@@ -725,6 +725,7 @@ int  sas_discover_sata(struct domain_device *);
 int  sas_discover_end_dev(struct domain_device *);
 
 void sas_unregister_dev(struct asd_sas_port *port, struct domain_device *);
+int sas_queuecommand_internal(struct Scsi_Host *shost, struct scsi_cmnd *cmnd);
 
 void sas_init_dev(struct domain_device *);
 
@@ -756,4 +757,11 @@ void sas_notify_port_event(struct asd_sas_phy *phy, enum port_event event,
 void sas_notify_phy_event(struct asd_sas_phy *phy, enum phy_event event,
 			   gfp_t gfp_flags);
 
+static inline struct sas_task *sas_rq_to_task(struct request *rq)
+{
+	struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq);
+
+	return (struct sas_task *)(scmd + 1);
+}
+
 #endif /* _SASLIB_H_ */
-- 
2.26.2