[PATCH v2 3/3] xfs: allow linkat() on O_TMPFILE files

[Dave Chinner]

On Wed, Dec 18, 2013 at 08:22:41AM +0800, Zhi Yong Wu wrote:
> From: Zhi Yong Wu <wuzhy at linux.vnet.ibm.com>
> 
> The VFS allows an anonymous temporary file to be named at a later
> time via a linkat() syscall. The inodes for O_TMPFILE files are
> are marked with a special flag I_LINKABLE and have a zero link count.
> 
> To support this in XFS, xfs_link() detects if this flag I_LINKABLE
> is set and behaves appropriately when detected. So in this case,
> its transaciton reservation takes into account the additional
> overhead of removing the inode from the unlinked list. Then the
> inode is removed from the unlinked list and the directory entry
> is added. Finally its link count is bumped accordingly.
> 
> Signed-off-by: Zhi Yong Wu <wuzhy at linux.vnet.ibm.com>

Looks good.

Reviewed-by: Dave Chinner <dchinner at redhat.com>

-- 
Dave Chinner
david at fromorbit.com