Re: [PATCH] make last_inode counter in new_inode 32-bit on kernels that offer x86 compatability

[Andreas Dilger]

On Nov 06, 2006  15:36 -0600, Eric Sandeen wrote:
> OTOH if one filesystem (say, pipes) can wrap the numbers very quickly,
> while other spaces are otherwise more immune, then having it global puts
> everything using it at a bit more risk.

One option is having a per-sb counter (to avoid wraps on not-heavily-used
filesystems), and also a per-sb flag that indicates if the counter has
wrapped.  If that happens, it would be possible to do a lookup in the
inode hash for a conflicting inode number, and skip those.  It is more
overhead, but only hit in the case where there is danger (i.e. post wrap).

There should also be a flag indicating if the caller is actually using
the inum supplied by new_inode or not, to avoid the overhead if it just
replaces i_ino with its own value.

Cheers, Andreas
--
Andreas Dilger
Principal Software Engineer
Cluster File Systems, Inc.

-
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/