Re: [PATCH 0/2] unify DMA_..BIT_MASK definitions: v1

[Muli Ben-Yehuda <muli@il.ibm.com>]

On Tue, Sep 18, 2007 at 06:29:19AM +0200, Borislav Petkov wrote:
> These patches remove redundant DMA_..BIT_MASK definitions across two drivers.
> In this version of the patches, the computation of the bitmasks is done by
> the compiler.
> 
> Signed-off-by: Borislav Petkov <bbpetkov@yahoo.de>
> Cc: Jeremy Fitzhardinge <jeremy@goop.org>
> 
> --
> Index: 23-rc6/include/linux/dma-mapping.h
> ===================================================================
> --- 23-rc6/include/linux/dma-mapping.h.orig	2007-09-17 17:48:20.000000000 +0200
> +++ 23-rc6/include/linux/dma-mapping.h	2007-09-18 06:12:33.000000000 +0200
> @@ -13,16 +13,19 @@
>  	DMA_NONE = 3,
>  };
>  
> -#define DMA_64BIT_MASK	0xffffffffffffffffULL
> -#define DMA_48BIT_MASK	0x0000ffffffffffffULL
> -#define DMA_40BIT_MASK	0x000000ffffffffffULL
> -#define DMA_39BIT_MASK	0x0000007fffffffffULL
> -#define DMA_32BIT_MASK	0x00000000ffffffffULL
> -#define DMA_31BIT_MASK	0x000000007fffffffULL
> -#define DMA_30BIT_MASK	0x000000003fffffffULL
> -#define DMA_29BIT_MASK	0x000000001fffffffULL
> -#define DMA_28BIT_MASK	0x000000000fffffffULL
> -#define DMA_24BIT_MASK	0x0000000000ffffffULL
> +#define DMA_BIT_MASK(n)	((1ULL<<(n))-1)
> +
> +#define DMA_64BIT_MASK	DMA_BIT_MASK(64)

This one does not do what you mean. You need an explicit mask or a
~0ULL here.

Cheers,
Muli