[dm-devel] [PATCH v6 08/13] block: Add an explicit bio flag for bios that own their bvec

[Adrian Bunk]

On Wed, Aug 22, 2012 at 12:22:41PM -0700, Kent Overstreet wrote:
> On Wed, Aug 22, 2012 at 08:43:52PM +0300, Adrian Bunk wrote:
> > On Wed, Aug 22, 2012 at 10:04:05AM -0700, Kent Overstreet wrote:
> > >...
> > > --- a/include/linux/blk_types.h
> > > +++ b/include/linux/blk_types.h
> > > @@ -117,6 +117,7 @@ struct bio {
> > >   * BIO_POOL_IDX()
> > >   */
> > >  #define BIO_RESET_BITS	12
> > > +#define BIO_OWNS_VEC	12	/* bio_free() should free bvec */
> > >...
> > 
> > This doesn't look right.
> 
> Well, the first 12 bits are reset, so bit 12 will get preserved... I
> guess it's unusual to have a duplicated enum value like that but
> BIO_RESET_BITS is just a marker, not a real bit.

Wouldn't a BIO_RESET_MASK be better than BIO_RESET_BITS?

cu
Adrian

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