Re: [PATCH v6 1/5] dcache: export d_find_alias_rcu() for modular filesystems

[Christian Brauner]

On Sun, Oct 25, 2026 at 06:42:41PM +0000, Alex Markuze wrote:
> CephFS subvolume quarantine needs a dentry alias for its RCU ancestry
> walk without acquiring a dentry reference. d_find_alias_rcu() provides
> that lookup, but is unavailable to a modular Ceph client.
> 
> Export d_find_alias_rcu() to GPL modules. The Ceph quarantine state
> handling patch uses the export with the helper's RCU lifetime rules.
> 
> Signed-off-by: Alex Markuze <amarkuze@xxxxxxxxxx>
> ---
>  fs/dcache.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/fs/dcache.c b/fs/dcache.c
> index 1b1a81f10da67c608704383086c3facb64ee3b3b..13ba553081b33a54fd8d1cac5cbc55d0149e4ad7 100644
> --- a/fs/dcache.c
> +++ b/fs/dcache.c
> @@ -1248,6 +1248,7 @@ struct dentry *d_find_alias_rcu(struct inode *inode)
>  	spin_unlock(&inode->i_lock);
>  	return de;
>  }
> +EXPORT_SYMBOL_GPL(d_find_alias_rcu);

Please use EXPORT_SYMBOL_FOR_MODULES() and restrict this to ceph for now.