feat(lvm disk detection): add support to detect disks used by LVM localpv

[Ab-hishek]

Signed-off-by: Abhishek Agarwal abhishek.agarwal@mayadata.io

Why is this PR required? What issue does it fix?:
openebs/openebs#3407

What this PR does?:
This PR adds the functionality to detect disk that are used by lvm-locapv and tag them with block-device-tag=lvm-localpv during blockdevice creation.

Does this PR require any upgrade changes?:

If the changes in this PR are manually verified, list down the scenarios covered::
TODO: Manual test for the change

Any additional information for your reviewer? :
Mention if this PR is part of any design or a continuation of previous PRs

Checklist:

• Fixes: Add support to detect disks used by LVM localpv in NDM. openebs/openebs#3407
• PR Title follows the convention of <type>(<scope>): <subject>
• Has the change log section been updated?
• Commit has unit tests
• Commit has integration tests
• (Optional) Are upgrade changes included in this PR? If not, mention the issue/PR to track:
• (Optional) If documentation changes are required, which issue on https://github.com/openebs/openebs-docs is used to track them:

[codecov-commenter]

Codecov Report

Merging #619 (e209899) into master (426eeaa) will decrease coverage by 0.89%.
The diff coverage is 43.33%.

@@            Coverage Diff             @@
##           master     #619      +/-   ##
==========================================
- Coverage   47.26%   46.36%   -0.90%     
==========================================
  Files          78       78              
  Lines        3781     3811      +30     
==========================================
- Hits         1787     1767      -20     
- Misses       1838     1884      +46     
- Partials      156      160       +4     

Impacted Files	Coverage Δ
cmd/ndm_daemonset/probe/usedbyprobe.go	14.44% <0.00%> (-1.22%)	⬇️
cmd/ndm_daemonset/probe/addhandler.go	70.25% <56.52%> (-7.23%)	⬇️
cmd/ndm_daemonset/probe/eventhandler.go	30.55% <0.00%> (-8.34%)	⬇️
cmd/ndm_daemonset/probe/udevprobe.go	48.53% <0.00%> (-3.77%)	⬇️

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[akhilerm]

Is this a reliable way to check if the device is in use by LVM localPV. Because nodes having LVM setup will also have the same lvm filesystem on the disks.

we need to check if this method helps us to identify between lvm localPV and LVM that has been setup by user.

[akhilerm]

This same issue is there for cstor and zfs -localpv. To identify that, we check if the device is exclusively locked. which happens only if kernel zfs is using the disk.

[Ab-hishek]

Because nodes having LVM setup will also have the same lvm filesystem on the disks.

By this you mean, disks that are used manually by LVM utils?

[akhilerm]

@Ab-hishek Some changes are needed on how to differentiate between disks used by LVM localPV and LVM that has been setup by the user.