From 569d98e9caae425120bf28f6b440e6cc117abc0d Mon Sep 17 00:00:00 2001
From: Maurizio Lombardi <mlombard@redhat.com>
Date: Mon, 1 Feb 2016 14:44:22 +0100
Subject: [PATCH] udev: fibre channel: fix NPIV support

When using NPIV, you can create multiple virtual HBAs on top of the
physical one, this means that the physical N_Port can have multiple
port IDs associated to it.
Suppose a LUN is assigned to the physical HBA and to a virtual HBA,
in both cases the original code uses the ID of the physical HBA
to build the by-path link and udev will end up trying to create two by-path
links with the same name.

This patch fixes the problem by using the port ID of the virtual HBA
whenever it detects that the device belongs to a virtual HBA,
otherwise it uses the port ID of the physical HBA.

(cherry-picked from 155a760bcedd11b7f3b430350a46f10736286895)

Resolves: #1266934
---
 src/udev/udev-builtin-path_id.c | 27 ++++++++++++++++++++++++---
 1 file changed, 24 insertions(+), 3 deletions(-)

diff --git a/src/udev/udev-builtin-path_id.c b/src/udev/udev-builtin-path_id.c
index 9ca608468..695ac7fc1 100644
--- a/src/udev/udev-builtin-path_id.c
+++ b/src/udev/udev-builtin-path_id.c
@@ -92,6 +92,9 @@ static struct udev_device *skip_subsystem(struct udev_device *dev, const char *s
 static struct udev_device *handle_scsi_fibre_channel(struct udev_device *parent, char **path) {
         struct udev *udev  = udev_device_get_udev(parent);
         struct udev_device *targetdev;
+        struct udev_device *rportdev;
+        struct udev_device *hostdev;
+        struct udev_device *vportdev;
         struct udev_device *fcdev = NULL;
         const char *port;
         char *lun = NULL;
@@ -100,9 +103,27 @@ static struct udev_device *handle_scsi_fibre_channel(struct udev_device *parent,
         if (targetdev == NULL)
                 return NULL;
 
-        fcdev = udev_device_new_from_subsystem_sysname(udev, "fc_transport", udev_device_get_sysname(targetdev));
-        if (fcdev == NULL)
-                return NULL;
+        rportdev = udev_device_get_parent(targetdev);
+        if (rportdev == NULL)
+                goto skip_npiv_check;
+
+        hostdev = udev_device_get_parent(rportdev);
+        if (hostdev == NULL)
+                goto skip_npiv_check;
+
+        vportdev = udev_device_get_parent(hostdev);
+        if (vportdev == NULL)
+                goto skip_npiv_check;
+
+        fcdev = udev_device_new_from_subsystem_sysname(udev, "fc_vports", udev_device_get_sysname(vportdev));
+
+skip_npiv_check:
+        if (fcdev == NULL) {
+                fcdev = udev_device_new_from_subsystem_sysname(udev, "fc_transport", udev_device_get_sysname(targetdev));
+                if (fcdev == NULL)
+                        return NULL;
+        }
+
         port = udev_device_get_sysattr_value(fcdev, "port_name");
         if (port == NULL) {
                 parent = NULL;