Re: [PATCH] NFS: fix nfs_fetch_iversion()

["J. Bruce Fields" <bfields@redhat.com>]

On Wed, Mar 24, 2021 at 03:53:53PM -0400, trondmy@kernel.org wrote:
> From: Trond Myklebust <trond.myklebust@hammerspace.com>
> 
> The change attribute is always set by all NFS client versions so get rid
> of the open-coded version.

Thanks!

I'm unclear whether there's a user-visible bug here or whether it's
mainly cleanup?

--b.

> Fixes: 3cc55f4434b4 ("nfs: use change attribute for NFS re-exports")
> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
> ---
>  fs/nfs/export.c | 15 ++++-----------
>  1 file changed, 4 insertions(+), 11 deletions(-)
> 
> diff --git a/fs/nfs/export.c b/fs/nfs/export.c
> index f2b34cfe286c..b347e3ce0cc8 100644
> --- a/fs/nfs/export.c
> +++ b/fs/nfs/export.c
> @@ -171,17 +171,10 @@ static u64 nfs_fetch_iversion(struct inode *inode)
>  {
>  	struct nfs_server *server = NFS_SERVER(inode);
>  
> -	/* Is this the right call?: */
> -	nfs_revalidate_inode(server, inode);
> -	/*
> -	 * Also, note we're ignoring any returned error.  That seems to be
> -	 * the practice for cache consistency information elsewhere in
> -	 * the server, but I'm not sure why.
> -	 */
> -	if (server->nfs_client->rpc_ops->version >= 4)
> -		return inode_peek_iversion_raw(inode);
> -	else
> -		return time_to_chattr(&inode->i_ctime);
> +	if (nfs_check_cache_invalid(inode, NFS_INO_INVALID_CHANGE |
> +						   NFS_INO_REVAL_PAGECACHE))
> +		__nfs_revalidate_inode(server, inode);
> +	return inode_peek_iversion_raw(inode);
>  }
>  
>  const struct export_operations nfs_export_ops = {
> -- 
> 2.30.2
>