Re: [PATCH] ncpfs: move ioctl32 code to fs/ncpfs/ioctl.c

[Petr Vandrovec <petr@vandrovec.name>]

[removed linware@sh.cvut.cz - I believe it is dead...]

Arnd Bergmann wrote:
> The ncp specific compat ioctls are clearly local to one
> file system, so the code can better live there.
> 
> This version of the patch moves everything into the
> generic ioctl handler and uses it for both 32 and 64
> bit calls.
> 
> Petr, can you test this patch on a 64 bit system?

Yes, tomorrow (on amd64).

> @@ -544,6 +691,9 @@
>  			kfree(oldname);
>  			return 0;
>  		}
> +#ifdef CONFIG_COMPAT
> +	case NCP_IOC_GETPRIVATEDATA_32:
> +#endif
>  	case NCP_IOC_GETPRIVATEDATA:
>  		if (current->uid != server->m.mounted_uid) {
>  			return -EACCES;
...
> @@ -562,10 +722,23 @@
>  						 server->priv.data,
>  						 outl)) return -EFAULT;
>  			}
> -			if (copy_to_user(argp, &user, sizeof(user)))
> -				return -EFAULT;
> +			if (cmd == NCP_IOC_GETPRIVATEDATA) {
> +				if (copy_to_user(argp, &user, sizeof(user)))
> +					return -EFAULT;
> +			} else {
> +#ifdef CONFIG_COMPAT
> +				struct compat_ncp_privatedata_ioctl user32;
> +				user32.len = user.len;
> +				user32.data = (unsigned long) user.data;
> +				if (copy_to_user(&user32, argp, sizeof(user32)))
> +					return -EFAULT;
> +#endif
> +			}
>  			return 0;
>  		}

Although I understand that this code is correct, what about removing this second 
  #ifdef ?  gcc should realize it anyway that without CONFIG_COMPAT defined cmd 
must be equal to NCP_IOC_GETPRIVATEDATA, and having empty "else" variant is IMHO 
just asking for troubles.  Or what about

#ifdef CONFIG_COMPAT
     if (cmd == NCP_IOC_GETPRIVATEDATA_32) {
        struct ...
     } else
#endif
     if (copy_to_user(argp, &user, sizeof(user)))
        return -EFAULT;

							Thanks,
								Petr