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Date: Wed, 10 Jan 2007 15:51:33 -0600
From: Eric Sandeen <sandeen@redhat.com>
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To: Christoph Hellwig <hch@infradead.org>, Jeff Layton <jlayton@redhat.com>,
       linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
       esandeen@redhat.com, aviro@redhat.com
Subject: Re: [PATCH 2/3] change libfs sb creation routines to avoid collisions
 with their root inodes
References: <200701082047.l08KlDCa001921@dantu.rdu.redhat.com> <20070110212215.GB4425@infradead.org>
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Christoph Hellwig wrote:

> 
>>  		return -ENOMEM;
>> +	/* set to high value to try and avoid collisions with loop below */
>> +	inode->i_ino = 0xffffffff;
>> +	insert_inode_hash(inode);
> 
> This is odd.  Can't we just add some constant base to the loop below?
>
I thought the same thing, but Jeff pointed out that
nfsctl_transaction_write does ops based on inode numbers, and they maybe
can't move around?

        rv =  write_op[ino](file, data, size);

However, nfsd's call to simple_fill_super already sends in a set of
files starting at inode 2:

enum {
        NFSD_Root = 1,
        NFSD_Svc,
...

        static struct tree_descr nfsd_files[] = {
                [NFSD_Svc] = {".svc", &transaction_ops, S_IWUSR},
...
        return simple_fill_super(sb, 0x6e667364, nfsd_files);

which does...

      for (i = 0; !files->name || files->name[0]; i++, files++) {
                if (!files->name)
                        continue;
...
                inode->i_ino = i;

So I think it's already expecting the root inode at one, and the other
files starting at 2?

-Eric