fc transport: new attributes for NPIV

From: Andreas Herrmann <[email protected]>

[PATCH] fc transport: new attributes for NPIV

With NPort-Id-Virtualization (NPIV) "virtual" ports can be registered at an FC switch using one physical FC port. Using FDISC an already logged in port can login additional ports to the Fabric. Each addtional port gets assigned a new destination ID (see FDISC description in FC-FS). For problem determination it is useful to know not only the virtual port name and its associated port id but also the port name and port id of the physical port - the port that initially logged into the Fabric.

I suggest to add new attributes (physical_port_name and physical_port_id) to scsi_transport_fc.

Signed-off-by Andreas Herrmann <[email protected]>

---

 drivers/scsi/scsi_transport_fc.c |    7 +++++++
 include/scsi/scsi_transport_fc.h |    9 +++++++++
 2 files changed, 16 insertions(+), 0 deletions(-)

8f1f64a50977add786fdd14a0cbc13aae4bfa89f

drivers/scsi/scsi_transport_fc.c +7 -0

index 685b997..365529a 100644
@@ -295,6 +295,7 @@ static int fc_host_setup(struct transpor
 	 */
 	fc_host_node_name(shost) = -1;
 	fc_host_port_name(shost) = -1;
+	fc_host_physical_port_name(shost) = -1;
 	fc_host_supported_classes(shost) = FC_COS_UNSPECIFIED;
 	memset(fc_host_supported_fc4s(shost), 0,
 		sizeof(fc_host_supported_fc4s(shost)));

@@ -306,6 +307,7 @@ static int fc_host_setup(struct transpor
 		sizeof(fc_host_serial_number(shost)));
 
 	fc_host_port_id(shost) = -1;
+	fc_host_physical_port_id(shost) = -1;
 	fc_host_port_type(shost) = FC_PORTTYPE_UNKNOWN;
 	fc_host_port_state(shost) = FC_PORTSTATE_UNKNOWN;
 	memset(fc_host_active_fc4s(shost), 0,

@@ -795,6 +797,8 @@ static FC_CLASS_DEVICE_ATTR(host, suppor
 
 fc_private_host_rd_attr_cast(node_name, "0x%llx\n", 20, unsigned long long);
 fc_private_host_rd_attr_cast(port_name, "0x%llx\n", 20, unsigned long long);
+fc_private_host_rd_attr_cast(physical_port_name, "0x%llx\n", 20,
+			     unsigned long long);
 fc_private_host_rd_attr(symbolic_name, "%s\n", (FC_SYMBOLIC_NAME_SIZE +1));
 fc_private_host_rd_attr(maxframe_size, "%u bytes\n", 20);
 fc_private_host_rd_attr(serial_number, "%s\n", (FC_SERIAL_NUMBER_SIZE +1));

@@ -835,6 +839,7 @@ static FC_CLASS_DEVICE_ATTR(host, speed,
 
 
 fc_host_rd_attr(port_id, "0x%06x\n", 20);
+fc_host_rd_attr(physical_port_id, "0x%06x\n", 20);
 fc_host_rd_enum_attr(port_type, FC_PORTTYPE_MAX_NAMELEN);
 fc_host_rd_enum_attr(port_state, FC_PORTSTATE_MAX_NAMELEN);
 fc_host_rd_attr_cast(fabric_name, "0x%llx\n", 20, unsigned long long);

@@ -1160,6 +1165,7 @@ fc_attach_transport(struct fc_function_t
 	count=0;
 	SETUP_HOST_ATTRIBUTE_RD(node_name);
 	SETUP_HOST_ATTRIBUTE_RD(port_name);
+	SETUP_HOST_ATTRIBUTE_RD(physical_port_name);
 	SETUP_HOST_ATTRIBUTE_RD(supported_classes);
 	SETUP_HOST_ATTRIBUTE_RD(supported_fc4s);
 	SETUP_HOST_ATTRIBUTE_RD(symbolic_name);

@@ -1168,6 +1174,7 @@ fc_attach_transport(struct fc_function_t
 	SETUP_HOST_ATTRIBUTE_RD(serial_number);
 
 	SETUP_HOST_ATTRIBUTE_RD(port_id);
+	SETUP_HOST_ATTRIBUTE_RD(physical_port_id);
 	SETUP_HOST_ATTRIBUTE_RD(port_type);
 	SETUP_HOST_ATTRIBUTE_RD(port_state);
 	SETUP_HOST_ATTRIBUTE_RD(active_fc4s);

include/scsi/scsi_transport_fc.h +9 -0

index 394f14a..13a8171 100644
@@ -303,6 +303,7 @@ struct fc_host_attrs {
 	/* Fixed Attributes */
 	u64 node_name;
 	u64 port_name;
+	u64 physical_port_name;
 	u32 supported_classes;
 	u8  supported_fc4s[FC_FC4_LIST_SIZE];
 	char symbolic_name[FC_SYMBOLIC_NAME_SIZE];

@@ -312,6 +313,7 @@ struct fc_host_attrs {
 
 	/* Dynamic Attributes */
 	u32 port_id;
+	u32 physical_port_id;
 	enum fc_port_type port_type;
 	enum fc_port_state port_state;
 	u8  active_fc4s[FC_FC4_LIST_SIZE];

@@ -338,6 +340,8 @@ struct fc_host_attrs {
 	(((struct fc_host_attrs *)(x)->shost_data)->node_name)
 #define fc_host_port_name(x)	\
 	(((struct fc_host_attrs *)(x)->shost_data)->port_name)
+#define fc_host_physical_port_name(x)	\
+	(((struct fc_host_attrs *)(x)->shost_data)->physical_port_name)
 #define fc_host_supported_classes(x)	\
 	(((struct fc_host_attrs *)(x)->shost_data)->supported_classes)
 #define fc_host_supported_fc4s(x)	\

@@ -352,6 +356,8 @@ struct fc_host_attrs {
 	(((struct fc_host_attrs *)(x)->shost_data)->serial_number)
 #define fc_host_port_id(x)	\
 	(((struct fc_host_attrs *)(x)->shost_data)->port_id)
+#define fc_host_physical_port_id(x)	\
+	(((struct fc_host_attrs *)(x)->shost_data)->physical_port_id)
 #define fc_host_port_type(x)	\
 	(((struct fc_host_attrs *)(x)->shost_data)->port_type)
 #define fc_host_port_state(x)	\

@@ -388,6 +394,7 @@ struct fc_function_template {
 	void 	(*get_starget_port_id)(struct scsi_target *);
 
 	void 	(*get_host_port_id)(struct Scsi_Host *);
+	void 	(*get_host_physical_port_id)(struct Scsi_Host *);
 	void	(*get_host_port_type)(struct Scsi_Host *);
 	void	(*get_host_port_state)(struct Scsi_Host *);
 	void	(*get_host_active_fc4s)(struct Scsi_Host *);

@@ -426,6 +433,7 @@ struct fc_function_template {
 	/* host fixed attributes */
 	unsigned long	show_host_node_name:1;
 	unsigned long	show_host_port_name:1;
+	unsigned long	show_host_physical_port_name:1;
 	unsigned long	show_host_supported_classes:1;
 	unsigned long	show_host_supported_fc4s:1;
 	unsigned long	show_host_symbolic_name:1;

@@ -434,6 +442,7 @@ struct fc_function_template {
 	unsigned long	show_host_serial_number:1;
 	/* host dynamic attributes */
 	unsigned long	show_host_port_id:1;
+	unsigned long	show_host_physical_port_id:1;
 	unsigned long	show_host_port_type:1;
 	unsigned long	show_host_port_state:1;
 	unsigned long	show_host_active_fc4s:1;

Drop the physical_port_id attribute. I'm assuming that each virtual port shows up as a unique scsi_host, as the FC ports and SCSI views it has is unique to it's FC address (N_Port_ID). As such, the physical_port_id would be redundant with the port_id on the scsi_host that corresponds to the physical port. Rather than determine the relationship through scsi_host attributes, you would determine the relationship via multiple scsi_host children under the pci adapter under the device tree. Obviously, if you don't buy into the scsi_host per port_id relationship, things change and we should talk further.

As for physical_port_name, minimally, this should be changed to primary_port_name, per the standards terms. However, as this is meaningful only to a FC/NPIV savvy person - it may be better to simply have an attribute such as virtual_port=<true/false>. If false, then PPN is the port_name. If true, then you would use the same device tree relationship pointed out above to find out which of the peers to the scsi_host has virtual_port=true, then you have it's port_name, port_id, etc... Yes, it feels like a little more work, but I feel it's a better alternative as the spread of object information internally is limited, and the external view, which can be easily managed via scripts/tools has as much or more information available.