Subject: Re: [PATCH 01/20] net-core: extending (hw_/wanted_/vlan_)features fields to a bitmap.

From: Ben Hutchings <[email-masked]>
Date: Wed, 06 Apr 2011 02:27:51 +0100

On Tue, 2011-04-05 at 17:44 -0700, Mahesh Bandewar wrote:
> Converting current use of (hw_/wanted_/vlan_)features to
> legacy_(hw_/wanted_/vlan_)features to differntiate from the proposed usage.
[...]
> @@ -1029,44 +1065,51 @@ struct net_device {
>  	struct list_head	napi_list;
>  	struct list_head	unreg_list;
>  
> +#define DEV_FEATURE_WORDS	2
> +#define	DEV_FEATURE_BITS	(DEV_FEATURE_WORDS*sizeof(long)*BITS_PER_BYTE)
> +#define LEGACY_FEATURE_WORD	0
> +
>  	/* currently active device features */
> -	u32			features;
> +	unsigned long 		features;
>  	/* user-changeable features */
> -	u32			hw_features;
> +	DECLARE_BITMAP(hw_feature, DEV_FEATURE_BITS);
[...]

Sorry, you can't get rid of hw_features without converting all the
callers at the same time.  All code has to remain compilable after each
single commit.

Ben.

-- 
Ben Hutchings, Senior Software Engineer, Solarflare
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They asked us to note that Solarflare product names are trademarked.