Re: [dm-devel] [PATCH v2 08/26] block: Remove bi_idx references

[Kent Overstreet <koverstreet google com>]

On Thu, Sep 20, 2012 at 04:49:53PM -0700, Tejun Heo wrote:
> On Mon, Sep 10, 2012 at 05:22:19PM -0700, Kent Overstreet wrote:
> > These were harmless but uneccessary,andt getting rid of them makes the
> > code easier to audit since most of them need to be removed.
> 
> I find the descriptions a bit too terse.  Why do they need to be
> removed?  So, I suppose you wanted to say explicit initializations to
> 0 are unnecessary, but there are bio_segments() conversions too.
> 
> The patch is simple and this isn't a big deal but I really hope for
> better (correct) descriptions.

It's because for the bvec iterator stuff and immutable bvecs, direct
bi_idx usage tends to be either wrong or unnecessary - I had to audit
all the uses in the kernel.

Reason for doing it now is a later patch moves bi_idx (also bi_sector
and bi_size) into a different struct - so doing these cleanup patches
first means a bit less code churn.