Subject: Re: as long as we're hitting FFS...
To: Perry E. Metzger <>
From: Bill Studenmund <>
List: tech-kern
Date: 03/23/1999 16:38:04
On 23 Mar 1999, Perry E. Metzger wrote:

> As long as we're going to hit the inode format, and creating a new
> magic number, some things I'd like fixed from the wish list:

Our proposed change was a simple step towards larger inodes. (As I
mentioned on the phone) the main change was that fs's would look at the
magic number at mount, and note if it's the large magic number or the
current magic number. Then each call to DINODE_SIZE() passes in a 0
(current ffs) or a 1 (large-inode ffs).

Adding all of these features in one fell swoop would make the change big
enough to need lots of review.

> 1) Eliminate the remaining file size limits. As it stands, you can't
> actually have an FFS file of 2^63rd size, although the system calls
> are all fine.

That'd be nice. But need lots of review. :-)

> 2) Expand time in inodes to 64 bits of seconds. Sure, we have 39 years 
> to do it but I see no reason not to do it now given the relative
> expense of writing an inode to disk vs. the expense of the extra
> couple of operations.

My thought here was that there is a flags u_int32_t, and one of these bits
would indicate that times are in 64-bit mode.

> 3) Eliminate endianness of FFSes -- this is more controversial. Right
> now, we have bi-endian support, but it would be cool not to need it.

As stated in other mail, I don't really like this idea. :-)

> 4) GC old goo like the old uid/gid support.

Then we won't be able to mount Ultrix partitions. Not a big deal to me,
but could be to other port-pmax folks.

Take care,