Re: [PATCH 11/11] ext4: add cross rename support

[Miklos Szeredi]

On Fri, Jan 17, 2014 at 11:08 PM, J. Bruce Fields <bfields@xxxxxxxxxxxx> wrote:
> On Fri, Jan 17, 2014 at 11:53:07PM +1300, Michael Kerrisk (man-pages) wrote:
>> >        The following additional errors are defined for renameat2():
>> >
>> >        EOPNOTSUPP
>> >               The filesystem does not support a flag in flags
>>
>> This is not the usual error for an invalid bit flag. Please make it EINVAL.
>
> I agree that EINVAL makes sense for an invalid bit flag.
>
> But renameat2() can also fail when the caller passes a perfectly valid
> flags field but the paths resolve to a filesystem that doesn't support
> the RENAME_EXCHANGE operation.  EOPNOTSUPP looks more appropriate in
> that case.

OTOH, from the app's perspective, it makes little difference whether a
particular kernel doesn't support the reanameat2 syscall, or it
doesn't support RENAME_FOO flag or if it does support RENAME_FOO but
not in all filesystems.  In all those cases it has to just fall back
to something supported and it doesn't matter *why* it wasn't
supported.

Thanks,
Miklos
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/