On 8/3/2012 4:40 AM, Jack Morgenstein wrote:
> Reserve bits 26-31 for internal use by low-level drivers. Two
> such bits are used in the mlx4 driver SRIOV IB implementation.
> 
> These enum additions guarantee that the core layer will never use
> these bits, so that low level drivers may safely make use of them.
> 
> Signed-off-by: Jack Morgenstein <jackm-LDSdmyG8hGV8YrgS2mwiifqBs+8SCbDb@public.gmane.org>
> ---
>  include/rdma/ib_verbs.h |    3 +++
>  1 files changed, 3 insertions(+), 0 deletions(-)
> 
> diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
> index 07996af..46bc045 100644
> --- a/include/rdma/ib_verbs.h
> +++ b/include/rdma/ib_verbs.h
> @@ -614,6 +614,9 @@ enum ib_qp_type {
>  enum ib_qp_create_flags {
>  	IB_QP_CREATE_IPOIB_UD_LSO		= 1 << 0,
>  	IB_QP_CREATE_BLOCK_MULTICAST_LOOPBACK	= 1 << 1,
> +	/* reserve bits 26-31 for low level drivers' internal use */
> +	IB_QP_CREATE_RESERVED_START		= 1 << 26,
> +	IB_QP_CREATE_RESERVED_END		= 1 << 31,
>  };
>  
>  struct ib_qp_init_attr {
> 

Reserving 6 bits for driver use out of 32 seems reasonable.

Acked-by: Doug Ledford <dledford-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>

-- 
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