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Subject: Re: [PATCH] block: bio: use struct_size() in kmalloc()
To:     xiaolinkui <xiaolinkui@kylinos.cn>
Cc:     linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
References: <1558084350-25632-1-git-send-email-xiaolinkui@kylinos.cn>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <e46a73e2-b04d-371b-f199-e789dbdbd9fc@kernel.dk>
Date:   Fri, 17 May 2019 15:17:07 -0600
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On 5/17/19 3:12 AM, xiaolinkui wrote:
> One of the more common cases of allocation size calculations is finding
> the size of a structure that has a zero-sized array at the end, along
> with memory for some number of elements for that array. For example:
> 
> struct foo {
>     int stuff;
>     struct boo entry[];
> };
> 
> instance = kmalloc(sizeof(struct foo) + count * sizeof(struct boo), GFP_KERNEL);
> 
> Instead of leaving these open-coded and prone to type mistakes, we can
> now use the new struct_size() helper:
> 
> instance = kmalloc(struct_size(instance, entry, count), GFP_KERNEL);

Applied, thanks.

-- 
Jens Axboe