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Date: Sat, 22 Feb 2014 09:06:25 -0500
From: "Theodore Ts'o" <tytso@mit.edu>
To: Namjae Jeon <linkinjeon@gmail.com>
Cc: viro@zeniv.linux.org.uk, david@fromorbit.com, bpm@sgi.com,
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        Namjae Jeon <namjae.jeon@samsung.com>,
        Ashish Sangwan <a.sangwan@samsung.com>
Subject: Re: [PATCH v5 1/10] fs: Add new flag(FALLOC_FL_COLLAPSE_RANGE) for
 fallocate
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On Wed, Feb 19, 2014 at 01:37:43AM +0900, Namjae Jeon wrote:
> +	/*
> +	 * There is no need to overlap collapse range with EOF, in which case
> +	 * it is effectively a truncate operation
> +	 */
> +	if ((mode & FALLOC_FL_COLLAPSE_RANGE) &&
> +	    (offset + len >= i_size_read(inode)))
> +		return -EINVAL;
> +

I wonder if we should just translate a collapse range that is
equivalent to a truncate operation to, in fact, be a truncate
operation?

						- Ted