Re: [PATCH 1/4] fsx: add missing file size update on zero range operations

[Eryu Guan <guan@eryu.me>]

On Wed, Apr 08, 2020 at 11:35:52AM +0100, fdmanana@kernel.org wrote:
> From: Filipe Manana <fdmanana@suse.com>
> 
> When a zero range operation increases the size of the test file we were
> not updating the global variable 'file_size' which tracks the current
> size of the test file. This variable is used to for example compute the
> offset for a source range of clone, dedupe and copy file range operations.
> 
> So just fix it by updating the 'file_size' global variable whenever a zero
> range operation does not use the keep size flag and its range goes beyond
> the current file size.
> 
> Signed-off-by: Filipe Manana <fdmanana@suse.com>
> ---
>  ltp/fsx.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/ltp/fsx.c b/ltp/fsx.c
> index 9d598a4f..fa383c94 100644
> --- a/ltp/fsx.c
> +++ b/ltp/fsx.c
> @@ -1212,6 +1212,8 @@ do_zero_range(unsigned offset, unsigned length, int keep_size)
>  	}
>  
>  	end_offset = keep_size ? 0 : offset + length;
> +	if (!keep_size && end_offset > file_size)
> +		file_size = end_offset;

I think this should be done after we really excute fallocate(2),
otherwise we may return early below:

        if (testcalls <= simulatedopcount)                                                                                                                                                                                                     
	                return;

Thanks,
Eryu

>  
>  	if (end_offset > biggest) {
>  		biggest = end_offset;
> -- 
> 2.11.0
>