Re: kern/41068: tmpfs assertion

[Andrew Doran <ad%netbsd.org@localhost>]

The following reply was made to PR kern/41068; it has been noted by GNATS.

From: Andrew Doran <ad%netbsd.org@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: 
Subject: Re: kern/41068: tmpfs assertion
Date: Wed, 8 Apr 2009 19:16:26 +0000

 On Wed, Apr 08, 2009 at 10:10:05AM +0000, Joerg Sonnenberger wrote:
 
 >  >  On Mon, Apr 06, 2009 at 02:00:07PM +0000, Joerg Sonnenberger wrote:
 >  >   >>  This cookie scheme is clearly not workable.
 >  >   >>  
 >  >   >>  Why doesn't it just assign sequence numbers to each node or 
 > something?
 >  >   >  
 >  >   > Because Linux compat would fall apart with that rather badly.
 >  >  
 >  >  Linux compat would fall over on small integers? What on earth are they
 >  >  doing? 
 >  
 >  What small numbers do you have in mind? If you don't want to do all the
 >  dance with checking for duplicates, you have to use 64bit numbers.
 >  ...and those are a problem for 32bit readdir applications.
 
 It could be solved by creating a vmem. See subr_percpu.c. This would give
 mostly lockless allocation of IDs and could also be used for inode numbers.