Add WithLoopDevices to report loop devices

[Itxaka]

Currently we skipp over all loop devices in the system and with no possibility of reporting those.

This patch introduces a new option to Block that allows us to report loop devices as disk and their partitions like if they were normal disks.

This patch does not modify any existing functionality or alters anything with the default values.

With WithLoopDevices enabled this reports the same info for loop devices as with other disks, including size, fs, mountpoints and so on.

Signed-off-by: Itxaka igarcia@suse.com

[Itxaka]

@fromanirh any comments on this? thanks!

[ffromani]

thanks @Itxaka for your contribution! I'll review today/tomorrow

[jaypipes]

@Itxaka what is the use case for a go-hardware library tracking loopback devices? :)

[Itxaka]

well, we could make the same question about returning mount points and filesystems no? Those are not hardware related at all, more like system status, so thinking in terms of ghw providing info about the current system in which its running, I want to see all the mountpoints, including those from loop devices which are mounted. I.E. I want to scan all mountpoints in the system to do something with them, report of scan or whatever, loop devices mounted are part of that system.

Thats the best I can do to sell this feature LOL :P

If you want a specific use case, we use loop devices in our installer[0] to test real installs, not really to a real filesystem, but to a loop device so we dont break any real disks, so we do some partition discovery and mounting. We currently use lsblk directly, but it would be much nicer to use a pure golang lib instead of depending on lsblk. Having loop mounts discovery in ghw helps us :)

[0] https://github.com/rancher-sandbox/elemental

[jaypipes]

well, we could make the same question about returning mount points and filesystems no? Those are not hardware related at all, more like system status, so thinking in terms of ghw providing info about the current system in which its running, I want to see all the mountpoints, including those from loop devices which are mounted. I.E. I want to scan all mountpoints in the system to do something with them, report of scan or whatever, loop devices mounted are part of that system.

Thats the best I can do to sell this feature LOL :P

If you want a specific use case, we use loop devices in our installer[0] to test real installs, not really to a real filesystem, but to a loop device so we dont break any real disks, so we do some partition discovery and mounting. We currently use lsblk directly, but it would be much nicer to use a pure golang lib instead of depending on lsblk. Having loop mounts discovery in ghw helps us :)

[0] https://github.com/rancher-sandbox/elemental

Fair enough. You've sold me on your use case.

I'll do a full review of the PR shortly.

[Itxaka]

any update on this @jaypipes ?

[Itxaka]

umm, failing on ubuntu but I cant reproduce it locally. As that its picking up the underlaying os devices Im sure there is something wrong in the code..Will try to debug

[Itxaka]

Found it, missing a value :D