Re: [Regression 6.1.y] From "cifs: Fix flushing, invalidation and file size with copy_file_range()"

[Matthew Wilcox <willy@xxxxxxxxxxxxx>]

On Fri, Jan 12, 2024 at 11:20:53PM -0600, Steve French wrote:
> Here is a patch similar to what David suggested.  Seems

Similar to, but worse.

> +++ b/fs/smb/client/cifsfs.c
> @@ -1240,7 +1240,7 @@ static int cifs_flush_folio(struct inode *inode, loff_t pos, loff_t *_fstart, lo
>  	int rc = 0;
>  
>  	folio = filemap_get_folio(inode->i_mapping, index);
> -	if (IS_ERR(folio))
> +	if ((!folio) || (IS_ERR(folio)))
>  		return 0;

filemap_get_folio() cannot return an err_ptr in 6.1, so this should
simply be:

-	if (IS_ERR(folio))
+	if (!folio)