Re: [PATCH 2/4] ipc: convert prepare_copy() from macro to function

[Andrew Morton <akpm@linux-foundation.org>]

On Wed, 07 Nov 2012 13:05:00 +0300
Stanislav Kinsbursky <skinsbursky@parallels.com> wrote:

> This code works if CONFIG_CHECKPOINT_RESTORE is disabled.
> 
> ...
>
> --- a/ipc/msg.c
> +++ b/ipc/msg.c
> @@ -803,8 +803,15 @@ static inline void free_copy(struct msg_msg *copy)
>  		free_msg(copy);
>  }
>  #else
> -#define prepare_copy(buf, sz, msgflg, msgtyp, copy_nr)	ERR_PTR(-ENOSYS)
>  #define fill_copy(copy_nr, msg_nr, msg, copy)		NULL
> +
> +static inline struct msg_msg *prepare_copy(void __user *buf, size_t bufsz,
> +					   int msgflg, long *msgtyp,
> +					   unsigned long *copy_number)
> +{
> +	return ERR_PTR(-ENOSYS);
> +}
> +
>  static inline void free_copy(struct msg_msg *copy)
>  {
>  }
> @@ -819,7 +826,7 @@ long do_msgrcv(int msqid, void __user *buf, size_t bufsz, long msgtyp,
>  	int mode;
>  	struct ipc_namespace *ns;
>  	struct msg_msg *copy = NULL;
> -	unsigned long __maybe_unused copy_number;
> +	unsigned long __maybe_unused copy_number = 0;

The __maybe_unused here makes no sense.  I'll remove it.

>  
>  	if (msqid < 0 || (long) bufsz < 0)
>  		return -EINVAL;