Re: CVS commit: src/sbin/umount

[Robert Elz <kre%munnari.OZ.AU@localhost>]

    Date:        Wed, 26 Mar 2025 20:46:42 +0000
    From:        David Holland <dholland-tech%netbsd.org@localhost>
    Message-ID:  <Z-RnsjlbKQxnCsTD%netbsd.org@localhost>

  | Because vnds are specifically configured for mounts; the only thing
  | they're useful for is mounting a fs image that lives in a regular
  | file.

No they're not, they can be used for playing with newfs variants,
fsdb, fsck, resize_ffs, ...   Nothing requires they be mounted.

  | It looks like we (still) don't have the ability to implicitly (or even
  | explicitly) configure a vnd when you try to mount a file, which Linux
  | has had for a long time. But we should really get that sometime.

Perhaps, but that's an unrelated issue.   And I suppose it should automatically
configure a cgd when you try to mount an encrypted file?

  | It's really fundamentally different from things like raids that have
  | independent existence.

I disagree, the only purpose of a raid is to provide filesystems (and perhaps
swap) which can be mounted - the only purpose of ccd is ... (and s/ccd/cgd/)
All these things model hardware devices in software, adding their own local
peculiarities (running in a file, redundancy, encryption, ...) but all of
them, vnd included, are more or less the same basic thing.

kre