feat(growpart): add LVM resize support

[xiachen-rh]

Fixes GH-3265

This change integrates LVM logical volume resizing into the existing growpart flow. When the target block device is an LVM LV, cloud-init now performs:

• lvs lookup to determine the volume group
• enumeration of PVs in the VG
• pvresize on each PV
• lvextend +100%FREE on the LV

Filesystem resizing is intentionally omitted because resizefs is handled by a separate module.

Unit tests have been added under test_cc_growpart.py to validate:

• successful pvresize and lvextend calls
• error propagation for failed operations

This change does not affect existing non-LVM growpart behaviour.

Redhat Jira ticket: [RFE][Azure]growpart fails to resize a root partition on LVM https://issues.redhat.com/browse/RHEL-107485

Test Steps

I tested it on Azure and AWS with rhel image, for example, Boot up a VM on Azure and change the os disk to bigger than 64G Check the rootlv partition size, the root partition size is extended after VM boot up.

[Before changes] The root partition size is not extended.

2025-07-25 10:04:34,238 - cc_growpart.py[DEBUG]: growpart found fs=xfs
2025-07-25 10:04:34,238 - distros[DEBUG]: /dev/mapper/rootvg-rootlv is a mapped device pointing to /dev/dm-1
2025-07-25 10:04:34,238 - subp.py[DEBUG]: Running command ['dmsetup', 'deps', '--options=devname', '/dev/mapper/rootvg-rootlv'] with allowed return codes [0] (shell=False, capture=True)
2025-07-25 10:04:34,246 - subp.py[DEBUG]: Running command ['cryptsetup', 'status', '/dev/dm-1'] with allowed return codes [0] (shell=False, capture=True)
2025-07-25 10:04:34,395 - performance.py[DEBUG]: Running ['cryptsetup', 'status', '/dev/dm-1'] took 0.149 seconds
2025-07-25 10:04:34,395 - subp.py[DEBUG]: Running command ['cryptsetup', 'isLuks', '/dev/sda4'] with allowed return codes [0] (shell=False, capture=True)
2025-07-25 10:04:34,469 - performance.py[DEBUG]: Running ['cryptsetup', 'isLuks', '/dev/sda4'] took 0.073 seconds
2025-07-25 10:04:34,469 - performance.py[DEBUG]: Resizing devices took 0.234 seconds
2025-07-25 10:04:34,469 - cc_growpart.py[DEBUG]: '/' SKIPPED: Resizing mapped device (/dev/mapper/rootvg-rootlv) skipped as it is not encrypted. 

[After changes] The root partition size is extended.

2025-11-25 05:55:00,763 - cc_growpart.py[DEBUG]: growpart found fs=xfs
2025-11-25 05:55:00,763 - distros[DEBUG]: /dev/mapper/rootvg-rootlv is a mapped device pointing to /dev/dm-1
2025-11-25 05:55:00,763 - subp.py[DEBUG]: Running command ['dmsetup', 'deps', '--options=devname', '/dev/mapper/rootvg-rootlv'] with allowed return codes [0] (shell=False, capture=True)
2025-11-25 05:55:00,766 - subp.py[DEBUG]: Running command ['cryptsetup', 'status', '/dev/dm-1'] with allowed return codes [0] (shell=False, capture=True)
2025-11-25 05:55:00,929 - performance.py[DEBUG]: Running ['cryptsetup', 'status', '/dev/dm-1'] took 0.164 seconds
2025-11-25 05:55:00,930 - subp.py[DEBUG]: Running command ['cryptsetup', 'isLuks', '/dev/sda4'] with allowed return codes [0] (shell=False, capture=True)
2025-11-25 05:55:01,001 - performance.py[DEBUG]: Running ['cryptsetup', 'isLuks', '/dev/sda4'] took 0.071 seconds
2025-11-25 05:55:01,001 - subp.py[DEBUG]: Running command ['lsblk', '-n', '-o', 'TYPE', '/dev/mapper/rootvg-rootlv'] with allowed return codes [0] (shell=False, capture=True)
2025-11-25 05:55:01,055 - performance.py[DEBUG]: Running ['lsblk', '-n', '-o', 'TYPE', '/dev/mapper/rootvg-rootlv'] took 0.053 seconds
2025-11-25 05:55:01,055 - util.py[DEBUG]: Reading from /sys/class/block/sda4/partition (quiet=False)
2025-11-25 05:55:01,055 - util.py[DEBUG]: Reading 2 bytes from /sys/class/block/sda4/partition
2025-11-25 05:55:01,055 - util.py[DEBUG]: Reading from /sys/devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A03:00/device:07/VMBUS:01/00000000-0000-8899-0000-000000000000/host0/target0:0:0/0:0:0:0/block/sda/dev (quiet=False)
2025-11-25 05:55:01,055 - util.py[DEBUG]: Reading 4 bytes from /sys/devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A03:00/device:07/VMBUS:01/00000000-0000-8899-0000-000000000000/host0/target0:0:0/0:0:0:0/block/sda/dev
2025-11-25 05:55:01,055 - util.py[DEBUG]: Reading from /proc/1239/mountinfo (quiet=False)
2025-11-25 05:55:01,055 - util.py[DEBUG]: Reading 3132 bytes from /proc/1239/mountinfo
2025-11-25 05:55:01,056 - util.py[DEBUG]: Reading from /proc/1239/mountinfo (quiet=False)
2025-11-25 05:55:01,056 - util.py[DEBUG]: Reading 3132 bytes from /proc/1239/mountinfo
2025-11-25 05:55:01,056 - subp.py[DEBUG]: Running command ['growpart', '--dry-run', '/dev/sda', '4'] with allowed return codes [0] (shell=False, capture=True)
2025-11-25 05:55:01,247 - performance.py[DEBUG]: Running ['growpart', '--dry-run', '/dev/sda', '4'] took 0.191 seconds
2025-11-25 05:55:01,247 - subp.py[DEBUG]: Running command ['growpart', '/dev/sda', '4'] with allowed return codes [0] (shell=False, capture=True)
2025-11-25 05:55:02,440 - performance.py[DEBUG]: Running ['growpart', '/dev/sda', '4'] took 1.193 seconds
2025-11-25 05:55:02,442 - cc_growpart.py[INFO]: starting LVM resize flow for /dev/mapper/rootvg-rootlv
2025-11-25 05:55:02,442 - subp.py[DEBUG]: Running command ['lvs', '--noheadings', '-o', 'vg_name', '/dev/mapper/rootvg-rootlv'] with allowed return codes [0] (shell=False, capture=True)
2025-11-25 05:55:02,467 - performance.py[DEBUG]: Running ['lvs', '--noheadings', '-o', 'vg_name', '/dev/mapper/rootvg-rootlv'] took 0.025 seconds
2025-11-25 05:55:02,467 - cc_growpart.py[DEBUG]: lv /dev/mapper/rootvg-rootlv belongs to vg rootvg
2025-11-25 05:55:02,467 - subp.py[DEBUG]: Running command ['vgs', '--noheadings', '-o', 'pv_name', '--separator', ' ', 'rootvg'] with allowed return codes [0] (shell=False, capture=True)
2025-11-25 05:55:02,486 - performance.py[DEBUG]: Running ['vgs', '--noheadings', '-o', 'pv_name', '--separator', ' ', 'rootvg'] took 0.019 seconds
2025-11-25 05:55:02,487 - subp.py[DEBUG]: Running command ['pvresize', '/dev/sda4'] with allowed return codes [0] (shell=False, capture=True)
2025-11-25 05:55:02,702 - performance.py[DEBUG]: Running ['pvresize', '/dev/sda4'] took 0.215 seconds
2025-11-25 05:55:02,702 - cc_growpart.py[INFO]: pvresize succeeded for /dev/sda4
2025-11-25 05:55:02,702 - subp.py[DEBUG]: Running command ['lvextend', '-l', '+100%FREE', '/dev/mapper/rootvg-rootlv'] with allowed return codes [0] (shell=False, capture=True)
2025-11-25 05:55:02,961 - performance.py[DEBUG]: Running ['lvextend', '-l', '+100%FREE', '/dev/mapper/rootvg-rootlv'] took 0.259 seconds
2025-11-25 05:55:02,961 - cc_growpart.py[INFO]: lvextend +100%FREE succeeded for /dev/mapper/rootvg-rootlv
2025-11-25 05:55:02,961 - performance.py[DEBUG]: Resizing devices took 2.198 seconds
2025-11-25 05:55:02,961 - cc_growpart.py[INFO]: '/' resized: changed (/dev/sda4) from 116510408192 to 127247826432
2025-11-25 05:55:02,961 - cc_growpart.py[INFO]: '/' resized: Successfully resized LVM device '/dev/mapper/rootvg-rootlv'
2025-11-25 05:55:02,961 - handlers.py[DEBUG]: finish: init-network/config-growpart: SUCCESS: config-growpart ran successfully and took 2.260 seconds
2025-11-25 05:55:02,963 - handlers.py[DEBUG]: start: init-network/config-resizefs: running config-resizefs with frequency always
2025-11-25 05:55:02,963 - helpers.py[DEBUG]: Running config-resizefs using lock (<cloudinit.helpers.DummyLock object at 0x7fa0730692e0>)
2025-11-25 05:55:02,964 - util.py[DEBUG]: Reading from /proc/1239/mountinfo (quiet=False)
2025-11-25 05:55:02,964 - util.py[DEBUG]: Reading 3132 bytes from /proc/1239/mountinfo
2025-11-25 05:55:02,964 - cc_resizefs.py[DEBUG]: resize_info: dev=/dev/mapper/rootvg-rootlv mnt_point=/ path=/
2025-11-25 05:55:02,964 - cc_resizefs.py[DEBUG]: Resizing / (xfs) using xfs_growfs /
2025-11-25 05:55:02,964 - subp.py[DEBUG]: Running command ('xfs_growfs', '/') with allowed return codes [0] (shell=False, capture=True)
2025-11-25 05:55:03,336 - performance.py[DEBUG]: Running ('xfs_growfs', '/') took 0.372 seconds
2025-11-25 05:55:03,336 - cc_resizefs.py[DEBUG]: Resized root filesystem (type=xfs, val=True)
2025-11-25 05:55:03,336 - handlers.py[DEBUG]: finish: init-network/config-resizefs: SUCCESS: config-resizefs ran successfully and took 0.373 seconds

I’ve added three unit tests. Please let me know if further coverage is needed.

The integration test case is copied from https://github.com/canonical/cloud-init/pull/887, however I did not test it because that I failed to set up the local integration test environment, I will run it later.

[dermotbradley]

I think there should be a configuration switch to control whether or not the LV is resized (the PV resize seems fine) - often when LVM is used there will be multiple LVs (i.e. for /home, for /var/log, etc) and so having the LV for rootfs ("/") be grown to use up the whole of the VG is likely to be undesirable.

Also the growpart script (from cloud-utils) has some pvresize functionality (I forget any issues with it) and so it doesn't make sense to have LVM functionality in both cloud-util's growpart and in cloud-init's growpart module.

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