From 82a80c72ede026e643d16372b5e4eb89354ba586 Mon Sep 17 00:00:00 2001
From: Steve Baker <sbaker@redhat.com>
Date: Tue, 8 Feb 2022 14:10:16 +1300
Subject: [PATCH] Auto-detect partition types for mounting more images

This change replaces the behaviour which makes assumptions about the
partition layout based simply on how many partitions there are.

Instead, attributes of the block device are used to infer whether the
partition is a boot, EFI, or root device.

This change is required to mount the RHEL-9 image, which is a
whole-disk image that has boot, EFI, and root partitions.

Images known to correctly mount with this change include:
overcloud-full.qcow2
overcloud-hardened-uefi-full.qcow2
CentOS-Stream-GenericCloud-8-20210603.0.x86_64.qcow2
CentOS-Stream-GenericCloud-9-20220127.0.x86_64.qcow2
rhel-guest-image-9.0-20220125.3.x86_64.qcow2
openSUSE-Leap-15.3.x86_64-NoCloud.qcow2
bionic-server-cloudimg-amd64.img
bionic-server-cloudimg-amd64.squashfs
debian-10-openstack-amd64.qcow2

A similar approach may be attempted to add rhel-9 support to
diskimage-builder extract-image.

This change also fixes an incorrect check path in the remove_device
function.

Change-Id: I4397a660e874ff351f5da697ddc504e0f2c8cf5a
---
 scripts/tripleo-mount-image | 88 ++++++++++++++++++++++++++++---------
 1 file changed, 68 insertions(+), 20 deletions(-)

diff --git a/scripts/tripleo-mount-image b/scripts/tripleo-mount-image
index 1658cff91..1790fac85 100755
--- a/scripts/tripleo-mount-image
+++ b/scripts/tripleo-mount-image
@@ -85,7 +85,7 @@ unmount_volume () {
 }
 
 remove_device () {
-    if [ -b "/dev/mapper/$1" ]; then
+    if [ -b "$1" ]; then
         dmsetup remove $1
     fi
 }
@@ -110,8 +110,62 @@ mount_image() {
     # activate new logical volumes, this is automatic in some environments
     vgchange -ay
 
-    if [ -b "${NBD_DEVICE}p3" ]; then
-        # 3 partitions in the image, so assume the first 2 are boot partitions
+    root_device=""
+    boot_device=""
+    efi_device=""
+
+    # wait for any sub-devices to appear
+    timeout 5 sh -c "while ! ls ${NBD_DEVICE}p* ; do sleep 1; done" || true
+
+    devices=$(ls -1 ${NBD_DEVICE}p*)
+    device_count=$(echo $devices | wc -w)
+    if [ $device_count == "0" ]; then
+        # if there are no partition devices, assume one root device
+        root_device=${NBD_DEVICE}
+    elif [ $device_count == "1" ]; then
+        # if there is one partition device, assume it is the root device
+        root_device=${devices}
+        devices=""
+    fi
+
+    for device in ${devices}; do
+        lsblk --nodeps -P --output-all $device
+        label=$(lsblk --nodeps --noheadings --output LABEL $device)
+        part_type_name=$(lsblk --nodeps --noheadings --output PARTTYPENAME $device)
+        part_label=$(lsblk --nodeps --noheadings --output PARTLABEL $device)
+
+        if [[ ${part_type_name} == "BIOS boot" ]] || [[ ${part_type_name} == "PowerPC PReP boot" ]]; then
+            # Ignore unmountable partition
+            continue
+        fi
+
+        # look for EFI partition to mount at /boot/efi
+        if [ -z "$efi_device" ]; then
+            if [[ ${part_type_name} == "EFI System" ]]; then
+                efi_device=$device
+                continue
+            fi
+        fi
+
+        # look for partition to mount as /boot, only the RHEL guest image is known
+        # to have this
+        if [ -z "$boot_device" ]; then
+            if [[ ${label} == "boot" ]]; then
+                boot_device=$device
+                continue
+            fi
+        fi
+
+        if [ -z "$root_device" ]; then
+            root_device=$device
+            continue
+        fi
+    done
+
+    if [ -z "$root_device" ]; then
+        echo "ERROR: No root device found to mount"
+        exit 1
+    else
         if [ -b "/dev/mapper/vg-lv_root" ]; then
             # a whole-disk overcloud with lvm volumes
             # for example, overcloud-hardened-uefi-full.qcow2
@@ -122,25 +176,18 @@ mount_image() {
                 mount_volume $device $MOUNT_DIR$path
             done
         else
-            # a whole-disk overcloud with a single root partition
-            # for example, overcloud-hardened-full.qcow2
-            mount ${NBD_DEVICE}p3 $MOUNT_DIR
-        fi
-        # the EFI partition may be the first or second, try both
-        if blkid -t PARTLABEL="ESP" ${NBD_DEVICE}p1 ; then
-            mount ${NBD_DEVICE}p1 $MOUNT_DIR/boot/efi
-        elif blkid -t PARTLABEL="ESP" ${NBD_DEVICE}p2 ; then
-            mount ${NBD_DEVICE}p2 $MOUNT_DIR/boot/efi
-        fi
-    else
-        # a partition image
-        # for example, overcloud-full.qcow2
-        if [ -b "${NBD_DEVICE}p1" ]; then
-            mount ${NBD_DEVICE}p1 $MOUNT_DIR
-        else
-            mount ${NBD_DEVICE} $MOUNT_DIR
+            # a simple root partition
+            mount $root_device $MOUNT_DIR
         fi
     fi
+    if [ ! -z "$boot_device" ]; then
+        # mount to /boot
+        mount $boot_device $MOUNT_DIR/boot
+    fi
+    if [ ! -z "$efi_device" ]; then
+        # mount to /boot/efi
+        mount $efi_device $MOUNT_DIR/boot/efi
+    fi
 }
 
 unmount_image() {
@@ -153,6 +200,7 @@ unmount_image() {
             unmount_volume $MOUNT_DIR$path
         done
         unmount_volume $MOUNT_DIR/boot/efi
+        unmount_volume $MOUNT_DIR/boot
         unmount_volume $MOUNT_DIR
     fi