Commit c6503be7 authored by Alok Tiwari's avatar Alok Tiwari Committed by Martin K. Petersen
Browse files

scsi: fc_transport: docs: Add documentation for FC Remote Ports 



This patch updates the scsi_fc_transport.rst documentation by replacing
the outdated << To Be Supplied >> placeholder under the "FC Remote Ports
(rports)" section with a detailed explanation of remote port
functionality in the Fibre Channel (FC) transport class.

The new documentation covers:

 - What rports are and their role in FC-based SCSI communication

 - Their representation in sysfs (/sys/class/fc_remote_ports/)

 - Common sysfs attributes such as (port_id, port_name, node_name, and
   port_state).

 - Their typical lifecycle (creation and removal)

 - Guidance for driver developers on using fc_remote_port_add() and
   fc_remote_port_delete()

This change improves the completeness and usefulness of the FC transport
documentation for developers and users interacting with Fibre Channel
drivers in the Linux SCSI subsystem

Signed-off-by: default avatarAlok Tiwari <alok.a.tiwari@oracle.com>
Link: https://lore.kernel.org/r/20250607162304.1765430-1-alok.a.tiwari@oracle.com


Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 8b0b1461

Documentation/scsi/scsi_fc_transport.rst

+34 −1
Original line number Diff line number Diff line
@@ -30,7 +30,40 @@ This file is found at Documentation/scsi/scsi_fc_transport.rst 


FC Remote Ports (rports)

========================

<< To Be Supplied >>



  In the Fibre Channel (FC) subsystem, a remote port (rport) refers to a

  remote Fibre Channel node that the local port can communicate with.

  These are typically storage targets (e.g., arrays, tapes) that respond

  to SCSI commands over FC transport.



  In Linux, rports are managed by the FC transport class and are

  represented in sysfs under:



    /sys/class/fc_remote_ports/



  Each rport directory contains attributes describing the remote port,

  such as port ID, node name, port state, and link speed.



  rports are typically created by the FC transport when a new device is

  discovered during a fabric login or scan, and they persist until the

  device is removed or the link is lost.



  Common attributes:

  - node_name: World Wide Node Name (WWNN).

  - port_name: World Wide Port Name (WWPN).

  - port_id: FC address of the remote port.

  - roles: Indicates if the port is an initiator, target, or both.

  - port_state: Shows the current operational state.



  After discovering a remote port, the driver typically populates a

  fc_rport_identifiers structure and invokes fc_remote_port_add() to

  create and register the remote port with the SCSI subsystem via the

  Fibre Channel (FC) transport class.



  rports are also visible via sysfs as children of the FC host adapter.



  For developers: use fc_remote_port_add() and fc_remote_port_delete() when

  implementing a driver that interacts with the FC transport class.





FC Virtual Ports (vports)