Minor change to lookup devices using blkid

Minor change to lookup devices using blkid and updating the upgradeSpec
if needed. This may be needed when running elemental upgrade in
multipathd systems

Signed-off-by: Gaurav Mehta <[email protected]>

Author: ibrokethecloud

cmd/config/config.go

@@ -468,6 +468,11 @@ func ReadUpgradeSpec(r *types.RunConfig, flags *pflag.FlagSet, recoveryOnly bool
 	} else {
 		err = upgrade.Sanitize()
 	}
+	if err != nil {
+		return nil, fmt.Errorf("failed sanitizing upgrade spec: %v", err)
+	}
+
+	err = config.ReconcileUpgradeSpec(upgrade)
 	r.Logger.Debugf("Loaded upgrade UpgradeSpec: %s", litter.Sdump(upgrade))
 	return upgrade, err
 }

pkg/config/config.go

@@ -18,6 +18,7 @@ package config
 
 import (
 	"fmt"
+	"os/exec"
 	"path/filepath"
 	"runtime"
 	"strings"
@@ -585,3 +586,54 @@ func NewBuildConfig(opts ...GenericOptions) *types.BuildConfig {
 	}
 	return b
 }
+
+// ReconcileUpgradeSpec will check current mounts which may differ from elemental disovery from /sys/block tree
+// as this skips multipathed devices which may be in use.
+func ReconcileUpgradeSpec(spec *v1.UpgradeSpec) error {
+	if spec.Partitions.State != nil {
+		if err := reconcilePartition(spec.Partitions.State); err != nil {
+			return err
+		}
+	}
+	if spec.Partitions.Recovery != nil {
+		if err := reconcilePartition(spec.Partitions.Recovery); err != nil {
+			return err
+		}
+	}
+
+	if spec.Partitions.Persistent != nil {
+		if err := reconcilePartition(spec.Partitions.Persistent); err != nil {
+			return err
+		}
+	}
+
+	if spec.Partitions.OEM != nil {
+		if err := reconcilePartition(spec.Partitions.OEM); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func reconcilePartition(part *v1.Partition) error {
+	discoveredMountDiskBytes, err := execBlkid(part.FilesystemLabel)
+	if err != nil {
+		return fmt.Errorf("error discovering current partition using label %s: %w", part.FilesystemLabel, err)
+	}
+
+	// trim space since `blkid` output has a newline in result
+	discoveredMount := strings.TrimSpace(string(discoveredMountDiskBytes))
+	if part.Path != discoveredMount {
+		part.Path = discoveredMount
+	}
+	return nil
+}
+func execBlkid(name string) ([]byte, error) {
+	path, err := exec.LookPath("blkid")
+	if err != nil {
+		return nil, err
+	}
+
+	blkidCmd := exec.Command(path, "-L", name)
+	return blkidCmd.Output()
+}