Re: [PATCH 1/5] ipc: add protected payload

[Richard Braun]

On Fri, Feb 21, 2014 at 12:48:49PM +0100, Justus Winter wrote:
> Add a field ip_protected_payload and a flag ip_has_protected_payload
> to struct ipc_port.

> diff --git a/ipc/ipc_port.h b/ipc/ipc_port.h
> index 27d2e49..4c7c742 100644
> --- a/ipc/ipc_port.h
> +++ b/ipc/ipc_port.h
> @@ -71,6 +71,10 @@ typedef unsigned int ipc_port_timestamp_t;
>  struct ipc_port {
>       struct ipc_target ip_target;
>  
> +     /* Flags.  */
> +     unsigned int    ip_has_protected_payload:1;     /* A pp has
> +                                                        been set.  */
> +
>       /* This points to the ip_target above if this port isn't on a port set;
>          otherwise it points to the port set's ips_target.  */
>       struct ipc_target *ip_cur_target;
> @@ -96,6 +100,7 @@ struct ipc_port {
>       mach_port_msgcount_t ip_msgcount;
>       mach_port_msgcount_t ip_qlimit;
>       struct ipc_thread_queue ip_blocked;
> +     unsigned long ip_protected_payload;
>  };

Increasing the port structure size by 4 bytes for a single bit is a
little frustrating. Instead, how about storing that bit in
ip_target.ipt_object.io_bits, right next to IO_BITS_ACTIVE ?

-- 
Richard Braun