linux-ext4 - Re: [PATCH] ext4: simplify 32bit calculation of lblk

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Message-ID: <ZC0J6I1pYNZBB30y@infradead.org>
Date:   Tue, 4 Apr 2023 22:40:56 -0700
From:   Christoph Hellwig <hch@...radead.org>
To:     wuchi <wuchi.zero@...il.com>
Cc:     tytso@....edu, adilger.kernel@...ger.ca, ojaswin@...ux.ibm.com,
        ritesh.list@...il.com, linux-ext4@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] ext4: simplify 32bit calculation of lblk

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?