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Date:   Tue, 28 Sep 2021 21:32:32 +0300
From:   Kari Argillander <kari.argillander@gmail.com>
To:     Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Cc:     ntfs3@lists.linux.dev, linux-kernel@vger.kernel.org,
        linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] fs/ntfs3: Forbid FALLOC_FL_PUNCH_HOLE for normal files
Message-ID: <20210928183232.qi63jh2feknm3e7t@kari-VirtualBox>
References: <fad6f129-c53f-d751-be43-c403b1031449@paragon-software.com>
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On Tue, Sep 28, 2021 at 08:25:58PM +0300, Konstantin Komarov wrote:
> FALLOC_FL_PUNCH_HOLE isn't allowed with normal files.

But is this absolute or just for now it can't? In my mind this can be
done, but you are expert here. Please write about it here. This will
help who ever will implement this in future. Example why ntfs_zero_range
did not punch a hole for normal file. You did actually implement that
function for this purpose right?

> Fixes xfstest generic/016 021 022

Lot of grepping is done with these so use full format generic/xxx with
each of these.

Also this affects also to these, but I did not look if there is other
problems than punching.

  generic/012
  generic/177
  generic/255
  generic/316


Add fixes tag here.
> Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

> ---
>  fs/ntfs3/file.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/ntfs3/file.c b/fs/ntfs3/file.c
> index 5fb3508e5422..02ca665baa5f 100644
> --- a/fs/ntfs3/file.c
> +++ b/fs/ntfs3/file.c
> @@ -587,8 +587,8 @@ static long ntfs_fallocate(struct file *file, int mode, loff_t vbo, loff_t len)
>  		truncate_pagecache(inode, vbo_down);
>  
>  		if (!is_sparsed(ni) && !is_compressed(ni)) {
> -			/* Normal file. */
> -			err = ntfs_zero_range(inode, vbo, end);
> +			/* Normal file, can't make hole. */

If this is just for now plese write example
			/* TODO: Can't make hole to normal files yet. */

> +			err = -EOPNOTSUPP;
>  			goto out;
>  		}
>  
> -- 
> 2.33.0
>