From 0e58a78e4a65a3b47cc2edfab6850eb09c07480c Mon Sep 17 00:00:00 2001
From: Kevin Scott Adams <kevin.adams@ksatechnologies.com>
Date: Sun, 19 Aug 2018 16:35:28 -0400
Subject: [PATCH] Add functionality for iSCSI multipathing

- Added patch from @tl8roy to add multipathing to the ZFSPluging.pm for
FreeNAS. I believe this was only patched and tested for FreeNAS.  I
tested WITHOUT using multipathing and I have had no issues. Closes
enhancement request #15 and reference #11.
---
 perl5/PVE/Storage/ZFSPlugin.pm.patch | 77 +++++++++++++++++++++++++---
 1 file changed, 71 insertions(+), 6 deletions(-)

diff --git a/perl5/PVE/Storage/ZFSPlugin.pm.patch b/perl5/PVE/Storage/ZFSPlugin.pm.patch
index 32fd05d..c42814c 100644
--- a/perl5/PVE/Storage/ZFSPlugin.pm.patch
+++ b/perl5/PVE/Storage/ZFSPlugin.pm.patch
@@ -1,5 +1,5 @@
 --- ZFSPlugin.pm.orig	2018-05-16 04:06:14.000000000 -0400
-+++ ZFSPlugin.pm	2018-08-19 09:34:25.169349056 -0400
++++ ZFSPlugin.pm	2018-08-19 15:44:12.472851999 -0400
 @@ -10,6 +10,7 @@
  
  use base qw(PVE::Storage::ZFSPoolPlugin);
@@ -8,7 +8,14 @@
  use PVE::Storage::LunCmd::Istgt;
  use PVE::Storage::LunCmd::Iet;
  
-@@ -31,7 +32,7 @@
+@@ -25,13 +26,14 @@
+     modify_lu   => 1,
+     add_view    => 1,
+     list_view   => 1,
++    list_extent => 1,
+     list_lu     => 1,
+ };
+ 
  my $zfs_unknown_scsi_provider = sub {
      my ($provider) = @_;
  
@@ -17,7 +24,7 @@
  };
  
  my $zfs_get_base = sub {
-@@ -39,6 +40,8 @@
+@@ -39,6 +41,8 @@
  
      if ($scfg->{iscsiprovider} eq 'comstar') {
          return PVE::Storage::LunCmd::Comstar::get_base;
@@ -26,7 +33,7 @@
      } elsif ($scfg->{iscsiprovider} eq 'istgt') {
          return PVE::Storage::LunCmd::Istgt::get_base;
      } elsif ($scfg->{iscsiprovider} eq 'iet') {
-@@ -59,6 +62,8 @@
+@@ -59,6 +63,8 @@
      if ($lun_cmds->{$method}) {
          if ($scfg->{iscsiprovider} eq 'comstar') {
              $msg = PVE::Storage::LunCmd::Comstar::run_lun_command($scfg, $timeout, $method, @params);
@@ -35,7 +42,22 @@
          } elsif ($scfg->{iscsiprovider} eq 'istgt') {
              $msg = PVE::Storage::LunCmd::Istgt::run_lun_command($scfg, $timeout, $method, @params);
          } elsif ($scfg->{iscsiprovider} eq 'iet') {
-@@ -173,6 +178,22 @@
+@@ -155,6 +161,14 @@
+     return $class->zfs_request($scfg, undef, 'list_view', $guid);
+ }
+ 
++sub zfs_get_wwid_number {
++    my ($class, $scfg, $guid) = @_;
++
++    die "could not find lun_number for guid $guid" if !$guid;
++
++    return $class->zfs_request($scfg, undef, 'list_extent', $guid);
++}
++
+ # Configuration
+ 
+ sub type {
+@@ -173,6 +187,22 @@
  	    description => "iscsi provider",
  	    type => 'string',
  	},
@@ -58,7 +80,7 @@
  	# this will disable write caching on comstar and istgt.
  	# it is not implemented for iet. iet blockio always operates with
  	# writethrough caching when not in readonly mode
-@@ -204,6 +225,10 @@
+@@ -204,6 +234,10 @@
  	sparse => { optional => 1 },
  	comstar_hg => { optional => 1 },
  	comstar_tg => { optional => 1 },
@@ -69,3 +91,46 @@
  	content => { optional => 1 },
  	bwlimit => { optional => 1 },
      };
+@@ -225,7 +259,41 @@
+     my $guid = $class->zfs_get_lu_name($scfg, $name);
+     my $lun = $class->zfs_get_lun_number($scfg, $guid);
+ 
+-    my $path = "iscsi://$portal/$target/$lun";
++    my $wwid = $class->zfs_get_wwid_number($scfg, $guid);
++#    syslog(info,"JD: path get_lun_number guid $uid");
++
++    if ($wwid =~ /^([-\@\w.]+)$/) {
++        $wwid = $1;                    # $data now untainted
++    } else {
++        die "Bad data in '$wwid'";     # log this somewhere
++    }
++    my $wwid_end = substr $wwid, 16;
++
++    my $mapper = '';
++    sleep 3;
++    run_command("iscsiadm -m session --rescan");
++    sleep 3;
++    my $line = `multipath -ll | grep \"$wwid_end\"`;
++    my ($mapper_device) = split(' ', $line);
++    $mapper_device = "" unless $mapper_device;
++    $mapper .= $mapper_device;
++
++    my $path = "";
++
++    if ($mapper =~ /^([-\@\w.]+)$/) {
++        $mapper = $1;                  # $data now untainted
++    } else {
++        $mapper = '';
++    }
++
++#    syslog(info,"Mapper: $mapper\n");
++    if ($mapper eq "")
++    {
++        $path = "iscsi://$portal/$target/$lun";
++    } else {
++        $path = "/dev/mapper/$mapper";
++        sleep 5;
++    }
+ 
+     return ($path, $vmid, $vtype);
+ }