fix(ibmcloud): reliably mount IBM Power data volume at /home

Replace inline runcmd polling with a systemd oneshot service that waits
for the multipath data volume before formatting and mounting it at /home.

Key fixes:
- lsblk -d silently excludes holder/mapper devices on multipath systems;
  switch to lsblk -r and detect the data volume by finding the mpath
  device that has no partition children
- Add udevadm settle + 10s pause before mkfs to let multipathd finish
  internal bookkeeping after the mapper device becomes visible
- Use mkfs.xfs -K to skip block discard on SAN storage

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: adrianriobo

pkg/provider/ibmcloud/action/ibm-power/cloud-config

@@ -1,6 +1,47 @@
 #cloud-config
-{{- if or .OtelColScript .GitLabRunnerScript}}
 write_files:
+  - path: /usr/local/bin/mount-data-home.sh
+    permissions: '0700'
+    owner: root:root
+    content: |
+      #!/bin/bash
+      set -euo pipefail
+      if mountpoint -q /home; then
+        exit 0
+      fi
+      DATA_DEV=""
+      while true; do
+        DATA_DEV=$(lsblk -rnpo NAME,TYPE | awk '$2=="mpath"{mpath[$1]=1} $2=="part"{p=$1; sub(/p[0-9]+$/,"",p); has_part[p]=1} END{for(d in mpath) if(!has_part[d]&&d!~/control/) print d}' | head -1)
+        [ -n "$DATA_DEV" ] && break
+        udevadm trigger --subsystem-match=block 2>/dev/null || true
+        udevadm settle 2>/dev/null || true
+        multipathd reconfigure 2>/dev/null || true
+        sleep 10
+      done
+      udevadm settle 2>/dev/null || true
+      sleep 10
+      mkfs.xfs -f -K "$DATA_DEV"
+      UUID=$(blkid -s UUID -o value "$DATA_DEV")
+      mkdir -p /mnt/home-tmp
+      cp -a /home/. /mnt/home-tmp/
+      mount "$DATA_DEV" /home
+      cp -a /mnt/home-tmp/. /home/
+      rm -rf /mnt/home-tmp
+      echo "UUID=$UUID /home xfs defaults 0 2" >> /etc/fstab
+  - path: /etc/systemd/system/mount-data-home.service
+    permissions: '0644'
+    content: |
+      [Unit]
+      Description=Mount data volume at /home
+
+      [Service]
+      Type=oneshot
+      ExecStart=/usr/local/bin/mount-data-home.sh
+      RemainAfterExit=yes
+      TimeoutStartSec=0
+
+      [Install]
+      WantedBy=multi-user.target
 {{- if .OtelColScript}}
   - path: /opt/install-otelcol.sh
     permissions: '0700'
@@ -33,31 +74,14 @@ write_files:
     content: |
 {{.GitLabRunnerScript}}
 {{- end}}
-{{- end}}
 runcmd:
-  - |
-    udevadm settle
-    DATA_DEV=""
-    for i in $(seq 1 24); do
-      DATA_DEV=$(lsblk -dpno NAME,PTTYPE | awk '$2=="" && $1 ~ /\/dev\/mapper\// && $1 !~ /control/ {print $1}' | head -1)
-      [ -n "$DATA_DEV" ] && break
-      sleep 5
-    done
-    if [ -n "$DATA_DEV" ]; then
-      mkfs.xfs -f "$DATA_DEV"
-      UUID=$(blkid -s UUID -o value "$DATA_DEV")
-      mkdir -p /mnt/home-tmp
-      cp -a /home/. /mnt/home-tmp/
-      mount "$DATA_DEV" /home
-      cp -a /mnt/home-tmp/. /home/
-      rm -rf /mnt/home-tmp
-      echo "UUID=$UUID /home xfs defaults 0 2" >> /etc/fstab
-    fi
+  - systemctl enable mount-data-home.service
   - dnf install -y git podman
   - |
     IFACE=$(ip route show default | awk '/default/ {print $5; exit}')
     ip route add 10.0.0.0/8 via {{.Gateway}} dev "$IFACE" 2>/dev/null || true
     echo "10.0.0.0/8 via {{.Gateway}}" > "/etc/sysconfig/network-scripts/route-$IFACE"
+  - systemctl start mount-data-home.service
 {{- if .OtelColScript}}
   - bash /opt/install-otelcol.sh
 {{- end}}

pkg/provider/ibmcloud/action/ibm-power/ibm-power_test.go

@@ -24,8 +24,8 @@ func TestPiUserData_noRunner(t *testing.T) {
 	if strings.Contains(cfg, "install-glrunner") {
 		t.Error("expected no GitLab runner section when script is empty")
 	}
-	if strings.Contains(cfg, "write_files") {
-		t.Error("expected no write_files when otel and runner are both absent")
+	if !strings.Contains(cfg, "mount-data-home") {
+		t.Error("expected mount-data-home service in write_files regardless of runner/otel config")
 	}
 }
 

pkg/provider/ibmcloud/action/ibm-z/cloud-config

@@ -35,24 +35,6 @@ write_files:
 {{- end}}
 {{- end}}
 runcmd:
-  - |
-    udevadm settle
-    DATA_DEV=""
-    for i in $(seq 1 24); do
-      DATA_DEV=$(lsblk -dpno NAME,PTTYPE | awk '$2=="" && $1 ~ /\/dev\/mapper\// && $1 !~ /control/ {print $1}' | head -1)
-      [ -n "$DATA_DEV" ] && break
-      sleep 5
-    done
-    if [ -n "$DATA_DEV" ]; then
-      mkfs.xfs -f "$DATA_DEV"
-      UUID=$(blkid -s UUID -o value "$DATA_DEV")
-      mkdir -p /mnt/home-tmp
-      cp -a /home/. /mnt/home-tmp/
-      mount "$DATA_DEV" /home
-      cp -a /mnt/home-tmp/. /home/
-      rm -rf /mnt/home-tmp
-      echo "UUID=$UUID /home xfs defaults 0 2" >> /etc/fstab
-    fi
   - apt-get update -y
   - apt-get install -y git podman
 {{- if .OtelColScript}}