Re: [PATCH v2 15/26] block: Add bio_copy_data()

From: Tejun Heo
Date: Thu Sep 20 2012 - 20:09:44 EST


On Thu, Sep 20, 2012 at 05:06:32PM -0700, Tejun Heo wrote:
> Hello,
>
> On Mon, Sep 10, 2012 at 05:22:26PM -0700, Kent Overstreet wrote:
> > +void bio_copy_data(struct bio *dst, struct bio *src)
> > +{
> ...
> > + src_p = kmap_atomic(src_bv->bv_page);
> > + dst_p = kmap_atomic(dst_bv->bv_page);
> > +
> > + memcpy(dst_p + dst_bv->bv_offset,
> > + src_p + src_bv->bv_offset,
> > + bytes);
> > +
> > + kunmap_atomic(dst_p);
> > + kunmap_atomic(src_p);
>
> Wrap these in preempt_disable/enable() to allow the function to be
> called from any context?

Ooh, and maybe return the amount of copied data?

--
tejun
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