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Date:   Wed, 30 Nov 2022 07:55:46 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Li Nan <linan122@huawei.com>
Cc:     tj@kernel.org, josef@toxicpanda.com, axboe@kernel.dk,
        cgroups@vger.kernel.org, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, yukuai3@huawei.com,
        yi.zhang@huawei.com
Subject: Re: [PATCH -next v2 1/9] blk-iocost: cleanup ioc_qos_write() and
 ioc_cost_model_write()
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 <20221130132156.2836184-2-linan122@huawei.com>
 <Y4d801NjwwT0voKA@infradead.org>
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On Wed, Nov 30, 2022 at 07:54:59AM -0800, Christoph Hellwig wrote:
> > +	ret = nbytes;
> 
> ret is an int which bytes is a size_t.  So we at least need a ssize_t
> instead for ret, and even that assumes nbytes never overflows a ssize_t.

A better way might be to initialize ret to 0 at declaration time and
then do

	if (ret)
		return ret;
	return nbytes;