lkml.org 
[lkml]   [2004]   [Feb]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: UTF-8 and case-insensitivity
Linus Torvalds wrote:
> > > For example, the rule can be that _any_ regular dentry create will
> > > invalidate all the "case-insensitive" dentries. Just to be simple about
> > > it.
> >
> > If that's the rule, then with exactly the same algorithmic efficiency,
> > readdir+dnotify can be used to maintain the cache in userspace
> > instead. There is nothing gained by using the helper module in that case.
>
> Wrong.
> Because the dnotify would trigger EVEN FOR SAMBA OPERATIONS.

Ah, I didn't know you meant "_any_ regular dentry create (except for
Samba operations)".

To apply that rule, you either need alternate versions of rename() and
other file syscalls, or something akin to a process-specific flag (set
by the helper module) saying that this is a Samba process and dentry
creation _by this process_ shouldn't invalidate case-insensitive
dentries.

And if you have either of those, the bit of code which says "don't
invalidate case-insenitive dentries because this is a Samba process"
can just as easily say "don't send dnotify events to the current
process".

And once you've done that, it's easier just to add a DN_IGNORE_SELF
flag to dnotify meaning to ignore events caused by the current
process, and forget about the helper module. That'd be useful for
other programs, too.

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

\
 
 \ /
  Last update: 2005-03-22 14:01    [W:0.294 / U:0.232 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site