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To: David Schultz <das@FreeBSD.ORG>
In-reply-to: Your message of "Fri, 25 Mar 2005 22:10:18 EST."
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Date: Sat, 26 Mar 2005 09:02:09 +0000
From: David Malone <dwmalone@maths.tcd.ie>
Message-ID: <200503260902.ab77979@salmon.maths.tcd.ie>
cc: freebsd-fs@FreeBSD.ORG
Subject: Re: UFS Subdirectory limit. 
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> - make a new st_nlink field that's 32 bits and put it in the spare
>   32-bit field in struct stat

> - rename the old st_nlink to st_onlink and leave it at 16 bits

> - the kernel would fill in st_onlink with max(st_nlink,SHORT_MAX)

Hmmm - interesting - I hadn't realised there was spare space in
struct stat. I guess we could get away with this and there's space
in both ufs1 and ufs2 inodes. I think we'd need to redefinte nlink_t,
which would need an ABI bump.

One problem I can think of might be non-obvious failures of old
programs on directories with lots of subdirectories. The hacky
scheme ends up with a link count on 2 on all directories, which
produces a reasonably obvious failure.

	David.