linux-kernel - Re: [RFC PATCH V2 1/9] include/linux/pagemap.h: introduce attach/clear_page

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <4c177757-7e27-420e-621b-98353ec43ea1@cloud.ionos.com>
Date:   Fri, 1 May 2020 08:39:31 +0200
From:   Guoqing Jiang <guoqing.jiang@...ud.ionos.com>
To:     Matthew Wilcox <willy@...radead.org>
Cc:     linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
        hch@...radead.org, david@...morbit.com,
        Andrew Morton <akpm@...ux-foundation.org>,
        "Darrick J. Wong" <darrick.wong@...cle.com>,
        William Kucharski <william.kucharski@...cle.com>,
        "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>,
        Andreas Gruenbacher <agruenba@...hat.com>,
        Yang Shi <yang.shi@...ux.alibaba.com>,
        Yafang Shao <laoar.shao@...il.com>, Song Liu <song@...nel.org>,
        linux-raid@...r.kernel.org, Chris Mason <clm@...com>,
        Josef Bacik <josef@...icpanda.com>,
        David Sterba <dsterba@...e.com>, linux-btrfs@...r.kernel.org,
        Alexander Viro <viro@...iv.linux.org.uk>,
        Jaegeuk Kim <jaegeuk@...nel.org>, Chao Yu <chao@...nel.org>,
        linux-f2fs-devel@...ts.sourceforge.net, linux-xfs@...r.kernel.org,
        Anton Altaparmakov <anton@...era.com>,
        linux-ntfs-dev@...ts.sourceforge.net,
        Mike Marshall <hubcap@...ibond.com>,
        Martin Brandenburg <martin@...ibond.com>,
        devel@...ts.orangefs.org, Thomas Gleixner <tglx@...utronix.de>,
        Sebastian Andrzej Siewior <bigeasy@...utronix.de>,
        Roman Gushchin <guro@...com>,
        Andreas Dilger <adilger@...ger.ca>
Subject: Re: [RFC PATCH V2 1/9] include/linux/pagemap.h: introduce
 attach/clear_page_private

On 5/1/20 12:13 AM, Matthew Wilcox wrote:
> On Thu, Apr 30, 2020 at 11:44:42PM +0200, Guoqing Jiang wrote:
>> +/**
>> + * attach_page_private - attach data to page's private field and set PG_private.
>> + * @page: page to be attached and set flag.
>> + * @data: data to attach to page's private field.
>> + *
>> + * Need to take reference as mm.h said "Setting PG_private should also increment
>> + * the refcount".
>> + */
> I don't think this will read well when added to the API documentation.
> Try this:
>
> /**
>   * attach_page_private - Attach private data to a page.
>   * @page: Page to attach data to.
>   * @data: Data to attach to page.
>   *
>   * Attaching private data to a page increments the page's reference count.
>   * The data must be detached before the page will be freed.
>   */
>
>> +/**
>> + * clear_page_private - clear page's private field and PG_private.
>> + * @page: page to be cleared.
>> + *
>> + * The counterpart function of attach_page_private.
>> + * Return: private data of page or NULL if page doesn't have private data.
>> + */
> Seems to me that the opposite of "attach" is "detach", not "clear".
>
> /**
>   * detach_page_private - Detach private data from a page.
>   * @page: Page to detach data from.
>   *
>   * Removes the data that was previously attached to the page and decrements
>   * the refcount on the page.
>   *
>   * Return: Data that was attached to the page.
>   */

Thanks you very much, Mattew! Will change them in next version.

Best Regards,
Guoqing