zpool: activate: move mount check out and make program flow easier

Early return when mounted heuristics returns true, that allows to get
rid of an indentation level.

Moving the heuristic out makes the activate method smaller and easier
to grasp

Best viewed with ignoring whitespace changes (`git show -w`).

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>

diff --git a/PVE/Storage/ZFSPoolPlugin.pm b/PVE/Storage/ZFSPoolPlugin.pm
index c734429f93433456a62b83002e8cbedb46db5bfe..fe65ae457784a1e95d5611c601636c029968413b 100644 (file)
--- a/PVE/Storage/ZFSPoolPlugin.pm
+++ b/PVE/Storage/ZFSPoolPlugin.pm
@@ -522,6 +522,21 @@ sub volume_snapshot_list {
     return $snaps;
 }
 
+my sub dataset_mounted_heuristic {
+    my ($dataset) = @_;
+
+    my $mounts = PVE::ProcFSTools::parse_proc_mounts();
+    for my $mp (@$mounts) {
+       my ($what, $dir, $fs) = $mp->@*;
+       next if $fs ne 'zfs';
+       # check for root-dataset or any child-dataset (root-dataset could have 'canmount=off')
+       # If any child is mounted heuristically assume that `zfs mount -a` was successful
+       next if $what !~ m!^$dataset(?:/|$)!;
+       return 1;
+    }
+    return 0;
+}
+
 sub activate_storage {
     my ($class, $storeid, $scfg, $cache) = @_;
 
@@ -529,19 +544,7 @@ sub activate_storage {
     my $dataset = $scfg->{pool};
     my $pool = ($dataset =~ s!/.*$!!r);
 
-    my $dataset_mounted = sub {
-       my $mounts = PVE::ProcFSTools::parse_proc_mounts();
-       foreach my $mp (@$mounts) {
-           my ($what, $dir, $fs) = @$mp;
-           next if $fs ne 'zfs';
-           # check for root-dataset of storage or any child-dataset.
-           # root-dataset could have 'canmount=off'. If any child is mounted
-           # heuristically assume that `zfs mount -a` was successful
-           next if $what !~ m!^$dataset(?:/|$)!;
-           return 1;
-       }
-       return 0;
-    };
+    return 1 if dataset_mounted_heuristic($dataset); # early return
 
     my $pool_imported = sub {
        my @param = ('-o', 'name', '-H', $pool);
@@ -551,19 +554,17 @@ sub activate_storage {
        return defined($res) && $res =~ m/$pool/;
     };
 
-    if (!$dataset_mounted->()) {
-       if (!$pool_imported->()) {
-           # import can only be done if not yet imported!
-           my @param = ('-d', '/dev/disk/by-id/', '-o', 'cachefile=none', $pool);
-           eval { $class->zfs_request($scfg, undef, 'zpool_import', @param) };
-           if (my $err = $@) {
-               # just could've raced with another import, so recheck if it is imported
-               die "could not activate storage '$storeid', $err\n" if !$pool_imported->();
-           }
+    if (!$pool_imported->()) {
+       # import can only be done if not yet imported!
+       my @param = ('-d', '/dev/disk/by-id/', '-o', 'cachefile=none', $pool);
+       eval { $class->zfs_request($scfg, undef, 'zpool_import', @param) };
+       if (my $err = $@) {
+           # just could've raced with another import, so recheck if it is imported
+           die "could not activate storage '$storeid', $err\n" if !$pool_imported->();
        }
-       eval { $class->zfs_request($scfg, undef, 'mount', '-a') };
-       die "could not activate storage '$storeid', $@\n" if $@;
     }
+    eval { $class->zfs_request($scfg, undef, 'mount', '-a') };
+    die "could not activate storage '$storeid', $@\n" if $@;
     return 1;
 }