Re: dk for z/lvm volumes?

[Chavdar Ivanov <ci4ic4%gmail.com@localhost>]

On Thu, 27 Feb 2020 at 09:40, Michael van Elst <mlelstv%serpens.de@localhost> wrote:
>
> mlelstv%serpens.de@localhost (Michael van Elst) writes:
>
> >ci4ic4%gmail.com@localhost (Chavdar Ivanov) writes:
>
> >># ccdconfig -c ccd0 0 /dev/zvol/dsk/pail/nbsd1
> >>ccdconfig: ioctl (CCDIOCSET): /dev/ccd0d: Inappropriate ioctl for device
>
> >>Apparently not, in this case. I think the comments in the thread
> >>suggest that already.
>
> >This is different. The ccd driver can use a regular block device as
> >component and present the result as a disk. Something must be different
> >with a zvol or your system. In any case, the errno value (ENOTTY)
> >is bogus as CCDIOCSET is perfectly valid for the ccd driver.
>
>
> That's a bug in the zfs driver.
>
> ccd queries the geometry of the backend devices. This is first done
> with the DIOCGWEDGEINFO ioctl for wedges. The zfs driver implements
> a fake version that returns the string "ZFS" as the parent device.
> That is not sufficient to query the blocksize. Next the regular
> DIOCGPART ioctl for disk driver is tried but this isn't implemented
> for zfs.
>
> As a result you see the ENOTTY error for a not implemented ioctl.

This probably explains the panic I reported in the previous mail.

>
> --
> --
>                                 Michael van Elst
> Internet: mlelstv%serpens.de@localhost
>                                 "A potential Snark may lurk in every tree."



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