[PATCH pve-storage 4/9] luncmd: lio: modernize helpers

["Max R. Carrara" <m.carrara@proxmox.com>]

Modernize the `get_backstore_prefix()` and `extract_volname()` helpers
by making them "proper" private subs instead of lexically-scoped sub
references.

Refactor the body of `extract_volname()` by reducing nesting, more
modern syntax, and a little guard clause.

Signed-off-by: Max R. Carrara <m.carrara@proxmox.com>
---
 src/PVE/Storage/LunCmd/LIO.pm | 50 +++++++++++++++++++----------------
 1 file changed, 27 insertions(+), 23 deletions(-)

diff --git a/src/PVE/Storage/LunCmd/LIO.pm b/src/PVE/Storage/LunCmd/LIO.pm
index ae5f3188..abe0454b 100644
--- a/src/PVE/Storage/LunCmd/LIO.pm
+++ b/src/PVE/Storage/LunCmd/LIO.pm
@@ -207,37 +207,41 @@ my $execute_remote_command = sub {
     return $res;
 };
 
-# Get prefix for backstores
-my $get_backstore_prefix = sub {
+my sub get_backstore_prefix {
     my ($scfg) = @_;
     my $pool = $scfg->{pool};
     $pool =~ s/\//-/g;
     return $pool . '-';
-};
+}
 
 # extracts the ZFS volume name from a device path
-my $extract_volname = sub {
+my sub extract_volname {
     my ($scfg, $config, $lunpath) = @_;
-    my $volname = undef;
 
     my $base = get_base($scfg);
-    if ($lunpath =~ /^$base\/$scfg->{pool}\/([\w\-\.]+)$/) {
-        $volname = $1;
-        my $prefix = $get_backstore_prefix->($scfg);
-        my $id = "$scfg->{portal}.$scfg->{target}";
-        my $target = $config->{$id};
-        foreach my $lun (@{ $target->{luns} }) {
-            # If we have a lun with the pool prefix matching this vol, then return this one
-            # like pool-pve-vm-100-disk-0
-            # Else, just fallback to the old name scheme which is vm-100-disk-0
-            if ($lun->{storage_object} =~ /^$BACKSTORE\/($prefix$volname)$/) {
-                return $1;
-            }
+
+    $lunpath =~ m/^$base\/$scfg->{pool}\/(?<volname>[\w\-\.]+)$/;
+    my $volname = $+{volname};
+
+    if (!defined($volname)) {
+        return;
+    }
+
+    my $prefix = get_backstore_prefix($scfg);
+    my $id = "$scfg->{portal}.$scfg->{target}";
+    my $target = $config->{$id};
+
+    for my $lun ($target->{luns}->@*) {
+        # If we have a lun with the pool prefix matching this vol, then return this one
+        # like pool-pve-vm-100-disk-0
+        # Else, just fallback to the old name scheme which is vm-100-disk-0
+        if ($lun->{storage_object} =~ /^$BACKSTORE\/(?<volname>$prefix$volname)$/) {
+            return $+{volname};
         }
     }
 
     return $volname;
-};
+}
 
 # retrieves the LUN index for a particular object
 my $list_view = sub {
@@ -245,7 +249,7 @@ my $list_view = sub {
     my $lun = undef;
 
     my $object = $params[0];
-    my $volname = $extract_volname->($scfg, $config, $object);
+    my $volname = extract_volname($scfg, $config, $object);
     my $id = "$scfg->{portal}.$scfg->{target}";
     my $target = $config->{$id};
 
@@ -265,7 +269,7 @@ my $list_lun = sub {
     my ($scfg, $config, $timeout, $method, @params) = @_;
 
     my $object = $params[0];
-    my $volname = $extract_volname->($scfg, $config, $object);
+    my $volname = extract_volname($scfg, $config, $object);
     my $id = "$scfg->{portal}.$scfg->{target}";
     my $target = $config->{$id};
 
@@ -287,10 +291,10 @@ my $create_lun = sub {
     }
 
     my $device = $params[0];
-    my $volname = $extract_volname->($scfg, $config, $device);
+    my $volname = extract_volname($scfg, $config, $device);
     # Here we create a new device, so we didn't get the volname prefixed with the pool name
     # as extract_volname couldn't find a matching vol yet
-    $volname = $get_backstore_prefix->($scfg) . $volname;
+    $volname = get_backstore_prefix($scfg) . $volname;
     my $tpg = $scfg->{lio_tpg} || die "Target Portal Group not set, aborting!\n";
 
     # step 1: create backstore for device
@@ -333,7 +337,7 @@ my $delete_lun = sub {
     my $tpg = $scfg->{lio_tpg} || die "Target Portal Group not set, aborting!\n";
 
     my $path = $params[0];
-    my $volname = $extract_volname->($scfg, $config, $path);
+    my $volname = extract_volname($scfg, $config, $path);
     my $id = "$scfg->{portal}.$scfg->{target}";
     my $target = $config->{$id};
 
-- 
2.47.3