Re: [RFC 1/1] shiftfs: uid/gid shifting bind mount

[J. R. Okajima]

James Bottomley:
> Yes, I know the problem.  However, I believe most current linux
> filesystems no longer guarantee stable, for the lifetime of the file,
> inode numbers.  The usual docker container root is overlayfs, which,
> similarly doesn't support stable inode numbers.  I see the odd
> complaint about docker with overlayfs having unstable inode numbers,
> but none seems to have any serious repercussions.

I think it serious.
Reusing the backend fs' inum is a good approach which Amir wrote.
Based on this, I'd suggest you to support the hardlinks.

bakend_dentry = lookup_one_len()
if (d_inode->i_nlink != 1)
	shiftfs_inode = ilookup();
if (!shiftfs_inode) {
	shiftfs_inode = new_inode();
	shiftfs_inode->i_ino = bakend_dentry->d_inode->i_ino;
}


J. R. Okajima