[PATCH 58/71] xfs: garbage collect old cowextsz reservations

[Christoph Hellwig]

On Mon, Sep 26, 2016 at 02:52:09PM -0700, Darrick J. Wong wrote:
> On Sat, Sep 24, 2016 at 12:42:34PM -0700, Christoph Hellwig wrote:
> > On Thu, Aug 25, 2016 at 04:38:14PM -0700, Darrick J. Wong wrote:
> > > Trim CoW reservations made on behalf of a cowextsz hint if they get too
> > > old or we run low on quota, so long as we don't have dirty data awaiting
> > > writeback or directio operations in progress.
> > 
> > FYI, at least in your latest tree we only ever seem to set
> > xfs_inode_set_cowblocks_tag in xfs_swap_extents, so this effectively
> > isn't used during normal fs usage.
> 
> The tag should be set at the end of __xfs_iomap_write_delay if we're
> creating a DA reservation in the CoW fork. 

We'll need to add that call then, as your current tree still doesn't
have it.