# Re: \[PATCH v2 15/26\] block: Add bio\_copy\_data()

- From: Tejun Heo \<hidden\>
- Date: 2012-09-21 00:06:38 
- List: linux-bcache
- Page: https://ratatoskr.run/linux-bcache/2012/09/3926571
- Thread: https://ratatoskr.run/linux-bcache/2012/09/3920950/t.md

```text
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?

Thanks.

-- 
tejun
```