[PATCH RFC 2/6] scsi: scsi_transport_sas: Allocate end device target id in the rphy alloc

[John Garry <john.garry@xxxxxxxxxx>]

Currently the per-end device target id is allocated when adding the rphy,
which is when we execute the scan of the target.

However it will be useful to have the target id allocated earlier when
allocating the rphy for the end device. For libata we want to move to a
scheme of allocating the sdev early in the probe process and then later
executing the scan (for that target). As such, users of would libata would
require that the target id allocated earlier here (before the scan).

Signed-off-by: John Garry <john.garry@xxxxxxxxxx>
---
 drivers/scsi/scsi_transport_sas.c | 25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/drivers/scsi/scsi_transport_sas.c b/drivers/scsi/scsi_transport_sas.c
index 2f88c61216ee..56d325665bc7 100644
--- a/drivers/scsi/scsi_transport_sas.c
+++ b/drivers/scsi/scsi_transport_sas.c
@@ -1433,6 +1433,7 @@ static void sas_rphy_initialize(struct sas_rphy *rphy)
 struct sas_rphy *sas_end_device_alloc(struct sas_port *parent)
 {
 	struct Scsi_Host *shost = dev_to_shost(&parent->dev);
+	struct sas_host_attrs *sas_host = to_sas_host_attrs(shost);
 	struct sas_end_device *rdev;
 
 	rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
@@ -1455,6 +1456,10 @@ struct sas_rphy *sas_end_device_alloc(struct sas_port *parent)
 	sas_rphy_initialize(&rdev->rphy);
 	transport_setup_device(&rdev->rphy.dev);
 
+	mutex_lock(&sas_host->lock);
+	rdev->rphy.scsi_target_id = sas_host->next_target_id++;
+	mutex_unlock(&sas_host->lock);
+
 	return &rdev->rphy;
 }
 EXPORT_SYMBOL(sas_end_device_alloc);
@@ -1500,6 +1505,16 @@ struct sas_rphy *sas_expander_alloc(struct sas_port *parent,
 }
 EXPORT_SYMBOL(sas_expander_alloc);
 
+static bool sas_rphy_end_device_valid_tproto(struct sas_rphy *rphy)
+{
+	struct sas_identify *identify = &rphy->identify;
+
+	if (identify->target_port_protocols &
+	    (SAS_PROTOCOL_SSP | SAS_PROTOCOL_STP | SAS_PROTOCOL_SATA))
+		return true;
+	return false;
+}
+
 /**
  * sas_rphy_add  -  add a SAS remote PHY to the device hierarchy
  * @rphy:	The remote PHY to be added
@@ -1529,16 +1544,10 @@ int sas_rphy_add(struct sas_rphy *rphy)
 
 	mutex_lock(&sas_host->lock);
 	list_add_tail(&rphy->list, &sas_host->rphy_list);
-	if (identify->device_type == SAS_END_DEVICE &&
-	    (identify->target_port_protocols &
-	     (SAS_PROTOCOL_SSP | SAS_PROTOCOL_STP | SAS_PROTOCOL_SATA)))
-		rphy->scsi_target_id = sas_host->next_target_id++;
-	else if (identify->device_type == SAS_END_DEVICE)
-		rphy->scsi_target_id = -1;
 	mutex_unlock(&sas_host->lock);
 
 	if (identify->device_type == SAS_END_DEVICE &&
-	    rphy->scsi_target_id != -1) {
+	    sas_rphy_end_device_valid_tproto(rphy)) {
 		int lun;
 
 		if (identify->target_port_protocols & SAS_PROTOCOL_SSP)
@@ -1667,7 +1676,7 @@ static int sas_user_scan(struct Scsi_Host *shost, uint channel,
 	mutex_lock(&sas_host->lock);
 	list_for_each_entry(rphy, &sas_host->rphy_list, list) {
 		if (rphy->identify.device_type != SAS_END_DEVICE ||
-		    rphy->scsi_target_id == -1)
+		    !sas_rphy_end_device_valid_tproto(rphy))
 			continue;
 
 		if ((channel == SCAN_WILD_CARD || channel == 0) &&
-- 
2.35.3