netdev - Re: [PATCH 1/9] mm: add a "struct subpage" type containing a page, offset and length

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]

Date:	Mon, 10 Oct 2011 17:27:07 +0100
From:	Ian Campbell <Ian.Campbell@...rix.com>
To:	"netdev@...r.kernel.org" <netdev@...r.kernel.org>
CC:	"linux-mm@...ck.org" <linux-mm@...ck.org>,
	linux-kernel <linux-kernel@...r.kernel.org>,
	Jens Axboe <axboe@...nel.dk>,
	"Christoph Hellwig" <hch@...radead.org>
Subject: Re: [PATCH 1/9] mm: add a "struct subpage" type containing a page,
 offset and length

(reposting including LKML to catch other potential users)

Is this structure of any use to unify other instances of a similar
tuple, e.g. biovec, pagefrag etc?

Ian.

On Mon, 2011-10-10 at 12:11 +0100, Ian Campbell wrote:
> A few network drivers currently use skb_frag_struct for this purpose but I have
> patches which add additional fields and semantics there which these other uses
> do not want.
> 
> A structure for reference sub-page regions seems like a generally useful thing
> so do so instead of adding a network subsystem specific structure.
> 
> Signed-off-by: Ian Campbell <ian.campbell@...rix.com>
> Cc: linux-mm@...ck.org
> ---
>  include/linux/mm_types.h |   11 +++++++++++
>  1 files changed, 11 insertions(+), 0 deletions(-)
> 
> diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
> index 774b895..dc1d103 100644
> --- a/include/linux/mm_types.h
> +++ b/include/linux/mm_types.h
> @@ -135,6 +135,17 @@ struct page {
>  #endif
>  ;
>  
> +struct subpage {
> +	struct page *page;
> +#if (BITS_PER_LONG > 32) || (PAGE_SIZE >= 65536)
> +	__u32 page_offset;
> +	__u32 size;
> +#else
> +	__u16 page_offset;
> +	__u16 size;
> +#endif
> +};
> +
>  typedef unsigned long __nocast vm_flags_t;
>  
>  /*


--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html