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Date: Sun, 28 Feb 2016 08:08:01 -0800
From: Christoph Hellwig <hch@infradead.org>
To: Boaz Harrosh <boaz@plexistor.com>
Cc: Ming Lei <tom.leiming@gmail.com>, lsf-pc@lists.linuxfoundation.org,
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	Linux FS Devel <linux-fsdevel@vger.kernel.org>
Subject: Re: [Lsf-pc] [LSF/MM ATTEND] block: multipage bvecs
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On Sun, Feb 28, 2016 at 01:17:43PM +0200, Boaz Harrosh wrote:
> I don't know if you ever tried it but I did. If I take a regular
> SSD disk or a PCIE flash card that I have in my machine and
> I stick a pointer to a page and bv_len = PAGE_SIZE * 8 and call
> submit_bio, I get 8 pages worth of IO with a single bvec and it
> all just works.

No, it will break in all kinds of places.  Also you really should
never just setup bvecs yourself, please always use bio_add_page!