linux-kernel - Re: [PATCH v7 3/9] block: Add bio

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: <20120828203148.GB24608@dhcp-172-17-108-109.mtv.corp.google.com>
Date:	Tue, 28 Aug 2012 13:31:48 -0700
From:	Tejun Heo <tj@...nel.org>
To:	Kent Overstreet <koverstreet@...gle.com>
Cc:	linux-bcache@...r.kernel.org, linux-kernel@...r.kernel.org,
	dm-devel@...hat.com, vgoyal@...hat.com, mpatocka@...hat.com,
	bharrosh@...asas.com, Jens Axboe <axboe@...nel.dk>
Subject: Re: [PATCH v7 3/9] block: Add bio_reset()

Hello, Kent.

On Tue, Aug 28, 2012 at 10:37:30AM -0700, Kent Overstreet wrote:
> Reusing bios is something that's been highly frowned upon in the past,
> but driver code keeps doing it anyways. If it's going to happen anyways,
> we should provide a generic method.
> 
> This'll help with getting rid of bi_destructor - drivers/block/pktcdvd.c
> was open coding it, by doing a bio_init() and resetting bi_destructor.

Better to explain why some bio fields are re-ordered and why that
shouldn't make things worse cacheline-wise?

> +void bio_reset(struct bio *bio)
> +{

Function comment explaining what it does and why it does what it does
with integrity / bi_css / whatnot?

> +	unsigned long flags = bio->bi_flags & (~0UL << BIO_RESET_BITS);
> +
> +	if (bio_integrity(bio))
> +		bio_integrity_free(bio, bio->bi_pool);
> +
> +	bio_disassociate_task(bio);

Is this desirable?  Why?

Thanks.

-- 
tejun
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/