Revert "Fix #2020: use /sys to map nvmeXnY to nvmeX"

This reverts commit c3442aa554.

Nowadays, relying on 'readlink /sys/block/nvmeXnY/device' won't always
lead to the correct device, as reported in the community forum[0],
where it results in '../../nvme-subsys0' and there's no matching entry
under '/dev/'.

Since Linux kernel 5.4, in particular commit 733e4b69d508 ("nvme:
Assign subsys instance from first ctrl"), the problematic situation
from bug #2020 shouldn't happen anymore.

Stated more clearly by the commit's author here[1]:
> Indeed, that commit will make the naming a bit more sane and will
> definitely prevent mistaken identity. It is still possible to
> observe controllers with instances that don't match their
> namespaces, but it is impossible to get a namespace instance that
> matches a non-owning controller.

The only other user of get_sysdir_info() doesn't use the 'device'
entry, so reverting that part is fine too.

[0] https://forum.proxmox.com/threads/113962/
[1] https://github.com/linux-nvme/nvme-cli/issues/510#issuecomment-552508647

Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Tested-by: Stefan Hrdlicka <s.hrdlicka@proxmox.com>

PVE/Diskmanage.pm

@@ -93,11 +93,7 @@ sub get_smart_data {
     my $smartdata = {};
     my $type;
 
-    if ($disk =~ m!^/dev/(nvme\d+n\d+)$!) {
-	my $info = get_sysdir_info("/sys/block/$1");
-	$disk = "/dev/".($info->{device}
-	    or die "failed to get nvme controller device for $disk\n");
-    }
+    $disk =~ s/n\d+$// if $disk =~ m!^/dev/nvme\d+n\d+$!;
 
     my $cmd = [$SMARTCTL, '-H'];
     push @$cmd, '-A', '-f', 'brief' if !$healthonly;
@@ -377,10 +373,6 @@ sub get_sysdir_info {
     $data->{vendor} = file_read_firstline("$sysdir/device/vendor") || 'unknown';
     $data->{model} = file_read_firstline("$sysdir/device/model") || 'unknown';
 
-    if (defined(my $device = readlink("$sysdir/device"))) {
-	($data->{device}) = $device =~ m!([^/]+)$!; # strip directory and untaint
-    }
-
     return $data;
 }
 

test/disk_tests/nvme_smart/nvme0n1/device

@@ -1 +0,0 @@
-../nvme0