Re: [PATCH] NFS: nfs_rename() handle -ERESTARTSYS dentry left behind

[Jeff Layton <jlayton@redhat.com>]

On Thu, 2016-12-15 at 09:48 -0500, Benjamin Coddington wrote:
> An interrupted rename will leave the old dentry behind if the rename
> succeeds.  Fix this by forcing a lookup the next time through
> ->d_revalidate.
> 
> Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
> ---
>  fs/nfs/dir.c | 14 ++++++++++++--
>  1 file changed, 12 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
> index 5f1af4cd1a33..5d409616f77e 100644
> --- a/fs/nfs/dir.c
> +++ b/fs/nfs/dir.c
> @@ -2100,14 +2100,24 @@ int nfs_rename(struct inode *old_dir, struct dentry *old_dentry,
>  		d_rehash(rehash);
>  	trace_nfs_rename_exit(old_dir, old_dentry,
>  			new_dir, new_dentry, error);
> -	if (!error) {
> +
> +	switch (error) {
> +	case 0:
>  		if (new_inode != NULL)
>  			nfs_drop_nlink(new_inode);
>  		d_move(old_dentry, new_dentry);
>  		nfs_set_verifier(new_dentry,
>  					nfs_save_change_attribute(new_dir));
> -	} else if (error == -ENOENT)
> +		break;
> +	case -ENOENT:
>  		nfs_dentry_handle_enoent(old_dentry);
> +		break;
> +	case -ERESTARTSYS:
> +		/* The result of the rename is unknown. Play it safe by
> +		 * forcing a new lookup */
> +		nfs_force_lookup_revalidate(old_dir);
> +		nfs_force_lookup_revalidate(new_dir);
> +	}
>  
>  	/* new dentry created? */
>  	if (dentry)

Looks reasonable to me. 

Reviewed-by: Jeff Layton <jlayton@redhat.com>