Re: fishy ->put_inode usage in ntfs

[Christoph Hellwig <hch@lst.de>]

On Thu, Oct 14, 2004 at 02:26:45PM +0100, Anton Altaparmakov wrote:
> > I don't like filesystem doings things like this in ->put_inode at all,
> > and indeed the plan is to get rid of ->put_inode completely.  Why do
> > you need to hold an additional reference anyway?  What's so special
> > about the relation of these two inodes?
> 
> The bmp_ino is a virtual inode.  It doesn't exist on disk as an inode. 
> It is an NTFS attribute of the base inode.  It cannot exist without the
> base inode there.  You could neither read from nor write to this inode
> without its base inode being there and you couldn't even clear_inode()
> this inode without the base inode being there.  The reference is
> essential I am afraid.
> 
> If ->put_inode is removed then I will have to switch to using
> ntfs_attr_iget() each time or I will have to attach the inode in some
> other much hackier way that doesn't use the i_count and uses my ntfs
> private counter instead.

Coming back to this issue.  Why do you need to refcount bmp_ino at all?
Can someone ever grab a reference separate from it's master inode?