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Date:   Tue, 4 Apr 2023 22:40:56 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     wuchi <wuchi.zero@gmail.com>
Cc:     tytso@mit.edu, adilger.kernel@dilger.ca, ojaswin@linux.ibm.com,
        ritesh.list@gmail.com, linux-ext4@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] ext4: simplify 32bit calculation of lblk
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On Mon, Apr 03, 2023 at 09:53:04PM +0800, wuchi wrote:
> -			if (block > ext_block)
> -				return ext_pblk + (block - ext_block);
> -			else
> -				return ext_pblk - (ext_block - block);
> +			return ext_pblk + ((signed long long)block - (signed long long)ext_block);

And what exactly is the value add here, except for turning an easy
to parse statement into a complex expression using casts?