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Date:   Thu, 31 Mar 2022 19:50:05 +0000
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Jeff Layton <jlayton@kernel.org>
Cc:     ceph-devel@vger.kernel.org, xiubli@redhat.com, idryomov@gmail.com,
        lhenriques@suse.de, linux-fsdevel@vger.kernel.org,
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Subject: Re: [PATCH v12 01/54] vfs: export new_inode_pseudo
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 <20220331153130.41287-2-jlayton@kernel.org>
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On Thu, Mar 31, 2022 at 11:30:37AM -0400, Jeff Layton wrote:
> Ceph needs to be able to allocate inodes ahead of a create that might
> involve a fscrypt-encrypted inode. new_inode() almost fits the bill,
> but it puts the inode on the sb->s_inodes list and when we go to hash
> it, that might be done again.
> 
> We could work around that by setting I_CREATING on the new inode, but
> that causes ilookup5 to return -ESTALE if something tries to find it
> before I_NEW is cleared. This is desirable behavior for most
> filesystems, but doesn't work for ceph.
> 
> To work around all of this, just use new_inode_pseudo which doesn't add
> it to the sb->s_inodes list.

Umm...  I can live with that, but... why not just leave the hash insertion
until the thing is fully set up and you are ready to clear I_NEW?