miniboot: Use release-specific prestage data, handle subcloud downgrade

This commit handles the relocation of ostree_repo prestaging data from
/opt/platform-backup to /opt/platform-backup/<release>. The miniboot.cfg
kickstart now looks for prestaged data in the release-specific location.

We also handle the backup partition name change across CentOS/Debian. In
the case of a downgrade the CentOS miniboot kickstart code is updated to
use the partition GUID rather than LABEL or PARTLABEL. The GUID is
constant across all releases and is therefore a more reliable indicator
of the backup partition.

Tech debt: Fix the arbitrary wait sleep calls used when configuring
VLAN addressing. Now uses the more efficient wait_for_interface
approach for the VLAN links.

Test Plan
PASS:
- Boot with prestaged data under /opt/platform-backup/<release>/
  Ensure boot/install successfully uses prestaged data.
- Boot into older release under prestaged /opt/platform-backup/21.12
    - Test moving from 22.12 -> 21.12 and 21.12 -> 22.12
    - Ensure backup partition is found using GUID approach.
    - Ensure boot/install successfully uses prestaged data.
- Boot into both current and older release with no prestaged data
    - Test moving from 22.12 -> 21.12 and 21.12 -> 22.12
    - Ensure boot/install is successful.
- Boot subcloud with bootstrap_vlan, ensure that the wait_for_interface
  calls properly wait until the link is up.

Story: 2010611
Task: 47943
Depends-On: https://review.opendev.org/c/starlingx/distcloud/+/880789

Change-Id: I381b60285e9bfc375f01f45b79174b71da7f0565
Signed-off-by: Kyle MacLeod <kyle.macleod@windriver.com>

bsp-files/kickstarts/post_miniboot_controller.cfg

@@ -58,8 +58,8 @@
 
 SW_VERSION=xxxPLATFORM_RELEASExxx
 STAGING_DIR="platform-backup"
-BACKUP_PART_LABEL=Platform\\x20Backup
-BACKUP_DEVICE=/dev/disk/by-partlabel/${BACKUP_PART_LABEL}
+BACKUP_DEVICE=
+BACKUP_PART_GUID="BA5EBA11-0000-1111-2222-000000000002"
 BACKUP_MOUNT=/mnt/${STAGING_DIR}
 BOOTIMAGE_ISO=""
 
@@ -76,8 +76,17 @@ iso_check=false
 iso_mount=false
 prestaging_files=false
 
+# Search for a backup partition, using GUID (which appears lower case in the blkid output):
+while read -r device_path; do
+    if [ "$(blkid -p "${device_path}" | grep -c -i "${BACKUP_PART_GUID}")" -gt 0 ]; then
+        BACKUP_DEVICE=${device_path}
+        wlog "Found backup device: ${BACKUP_DEVICE}"
+        break
+    fi
+done <<<"$(lsblk --noheadings --list --path --output NAME)"
+
 # Look for and validate the local iso image
-if [ -e ${BACKUP_DEVICE} ]; then
+if [ -n "${BACKUP_DEVICE}" ] && [ -e "${BACKUP_DEVICE}" ]; then
     mkdir -p ${BACKUP_MOUNT}
     mount ${BACKUP_DEVICE} ${BACKUP_MOUNT} 2>/dev/null
     rc=$?
@@ -183,6 +192,7 @@ fi
 
 # Make sure the prestage directory exists, as well as the required subdirectories.
 exists_prestage=false
+ilog "${KS} Checking prestaged content PRESTAGE_DIR: ${PRESTAGE_DIR}"
 if [ ! -e ${PRESTAGE_DIR} ] || [ ! -e ${PRESTAGE_DIR}/Packages ] || [ ! -e ${PRESTAGE_DIR}/repodata ]; then
     exists_prestage=false
     wlog "${KS} Prestaged content not present"

kickstart/files/miniboot.cfg

@@ -1582,13 +1582,10 @@ else
     fi
     ilog "ip ${BOOTPARAM_IP_VER} link set up dev ${mgmt_dev}"
     ip ${BOOTPARAM_IP_VER} link set up dev ${mgmt_dev}
-    # TODO(kmacleod) change to wait_for_interface 60:
-    sleep 15
+    wait_for_interface ${mgmt_dev} 60
     ilog "ip ${BOOTPARAM_IP_VER} link set up dev ${mgmt_iface}"
     ip ${BOOTPARAM_IP_VER} link set up dev ${mgmt_iface}
-    # TODO(kmacleod) change to wait_for_interface 60:
-    ilog "Wait 10s to settle interface..."
-    sleep 10
+    wait_for_interface ${mgmt_iface} 60
 
     if [ -z "${BOOTPARAM_GW}" ]; then
         # No gateway
@@ -2049,28 +2046,29 @@ else
 
         backup_device=/dev/disk/by-partlabel/platform_backup
         backup_mount=/tmp/platform-backup
+        backup_mount_release="${backup_mount}"/xxxPLATFORM_RELEASExxx
 
-        ilog "Temporary backup mount is ${backup_mount}"
+        ilog "Temporary backup mount: ${backup_mount}, release: ${backup_mount_release}"
         mkdir -p "${backup_mount}"
         mount "${backup_device}" "${backup_mount}" 2>/dev/null
 
         # If ostree_repo is found at the mounted backup directory,
         # then set the ostree url to its location.
         remote_insturl=
-        if [ -e ${backup_mount}/ostree_repo ]; then
+        if [ -e ${backup_mount_release}/ostree_repo ]; then
             local_repo_check_fail=
             # Calculate local checksum and compare
-            checksum_file=${backup_mount}/.ostree_repo_checksum
+            checksum_file=${backup_mount_release}/.ostree_repo_checksum
             if [ -f "${checksum_file}" ]; then
                 checksum_from_file=$(cat "${checksum_file}")
-                ilog "Verifying checksum for prestaged ${backup_mount}/ostree_repo"
-                pushd ${backup_mount} > /dev/null
+                ilog "Verifying checksum for prestaged ${backup_mount_release}/ostree_repo"
+                pushd ${backup_mount_release} > /dev/null
                 checksum=$(find ostree_repo -type f -exec md5sum {} + | LC_ALL=C sort | md5sum | awk '{ print $1; }')
                 popd > /dev/null
                 if [ "${checksum}" = "${checksum_from_file}" ]; then
                     ilog "Verified ostree checksum: ${checksum}"
                 else
-                    elog "ostree checksum failed on ${backup_mount}/ostree_repo"
+                    elog "ostree checksum failed on ${backup_mount_release}/ostree_repo"
                     elog "Calulated checksum: ${checksum}"
                     elog "File checksum:      ${checksum_from_file}"
                     local_repo_check_fail=true
@@ -2079,8 +2077,8 @@ else
                 # No prestage checksum file is available. Use ostree fsck instead.
                 # The only problem with this is the length of time required for fsck to complete.
                 wlog "No ostree checksum file at ${checksum_file}. Performing ostree fsck instead."
-                if ! ostree --repo="${backup_mount}/ostree_repo" fsck; then
-                    elog "ostree fsck failed on prestaged ${backup_mount}/ostree_repo: reverting to remote pull"
+                if ! ostree --repo="${backup_mount_release}/ostree_repo" fsck; then
+                    elog "ostree fsck failed on prestaged ${backup_mount_release}/ostree_repo: reverting to remote pull"
                     local_repo_check_fail=true
                 fi
             fi
@@ -2088,13 +2086,13 @@ else
                 # Preserve remote_insturl for use in 2nd ostree pull below
                 remote_insturl=${insturl}
 
-                insturl="file:///${backup_mount}/ostree_repo"
+                insturl="file:///${backup_mount_release}/ostree_repo"
                 ilog "Setting insturl to ${insturl} to use prestaged ostree_repo"
             else
                 # Remove the corrupted ostree_repo.
                 # Avoid setting insturl which will revert to using a remote pull
-                elog "ostree integrity check failed: removing prestaged ${backup_mount}/ostree_repo"
-                rm -rf "${backup_mount}/ostree_repo"
+                elog "ostree integrity check failed: removing prestaged ${backup_mount_release}/ostree_repo"
+                rm -rf "${backup_mount_release}/ostree_repo"
                 elog "ostree integrity check failed: reverting to remote pull"
             fi
         fi