Re: [PATCH 13/35] fallthru: ext2 fallthru support

From: Jan Blunck
Date: Wed Apr 21 2010 - 04:42:20 EST


On Tue, Apr 20, Jamie Lokier wrote:

> Miklos Szeredi wrote:
> > On Mon, 19 Apr 2010, Valerie Aurora wrote:
> > > I don't recall there being any technical reason not to look up the
> > > real inode number. I just wrote it that we because I was lazy. So I
> > > like returning the directory's d_ino better than a single magic
> > > number, but I'd at least like to try returning the real inode number
> > > too.
> >
> > Note, "struct dirent" doesn't have d_dev, so you really can't return
> > the "real" inode number, that's on a different filesystem and just a
> > random number in the context of the the readdir in question.
>
> Agree. Does this inappropriate inode number for the union mount's
> st_dev happen with stat() on the actual files too? That could be bad.

No, for stat() you do a lookup and that is returning the correct dentry/inode
for the filesystem the name is on.

We just return the the fallthru directory entries to give userspace an offset
that they can seekdir() to.

Regards,
Jan

--
Jan Blunck <jblunck@xxxxxxx>
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