Re: [rfc] new stat*fs-like syscall?

[Jeff Garzik]

On 06/25/2010 12:01 AM, Nick Piggin wrote:
> So is "frsize" supposed to be the optimal block size, or what?
> f_bsize AFAIKS should be filesystem allocation block size because
> apparently some programs require it to calculate size of file on
> disk.
>
> If we can't change existing suboptimal legacy things, then let's
> introduce new APIs that do the right thing. Apps that care will
> eventually start using eg. a new syscall.
>
> > > - statvfs(2) lacks f_type.
> > >
> > > Is there anything more we should add here? Samba wants a capabilities
> > > field, with things like sparse files, quotas, compression, encryption,
> > > case preserving/sensitive.
> >
> > It wouldn't be a bad idea, but then you could get into issues of what exactly the above flags mean.  That said, I think it is better to have broad categories of features that may be slightly ill-defined than having nothing at all.
>
> Yes it would be tricky. I don't want to add features that will just
> be useless or go unused, but I don't want to change the syscall API
> just to add f_flags, without looking at other possibilities.


It would be nice to separate capabilities and fixed parameters (block 
size) from statistics which change frequently (free space).

And are capabilities really suited to a C struct, at all?  That seems 
more suited to a key/value type interface, a la NFSv4 attributes.

	Jeff



--
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/