From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mahesh Bandewar <maheshb@google.com>
Subject: extending feature word.
Date: Fri, 1 Apr 2011 19:07:05 -0700
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Thanks for your comments on my loop-back patch. I was looking at the
code today from the perspective of extending various "features" for
word to an array of words and as Michael has pointed out, it's a huge
change. So I'm thinking on the following lines
(include/linux/netdevice.h)

+#define DEV_FEATURE_WORDS =A0 =A0 =A02
+#define LEGACY_FEATURE_WORD =A0 =A00
=A0 =A0 =A0 =A0/* currently active device features */
- =A0 =A0 =A0 u32 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 features;
+ =A0 =A0 =A0 u32 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 features[DEV_=
=46EATURE_WORDS];
=A0 =A0 =A0 =A0/* user-changeable features */
- =A0 =A0 =A0 u32 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 hw_features;
+ =A0 =A0 =A0 u32 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 hw_features[D=
EV_FEATURE_WORDS];
=A0 =A0 =A0 =A0/* user-requested features */
- =A0 =A0 =A0 u32 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 wanted_featur=
es;
+ =A0 =A0 =A0 u32 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 wanted_featur=
es[DEV_FEATURE_WORDS];
=A0 =A0 =A0 =A0/* VLAN feature mask */
- =A0 =A0 =A0 u32 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 vlan_features=
;
+ =A0 =A0 =A0 u32 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 vlan_features=
[DEV_FEATURE_WORDS];
+#define legacy_features =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0features[LEGACY=
_FEATURE_WORD]
+#define legacy_hw_features =A0 =A0 hw_features[LEGACY_FEATURE_WORD]
+#define legacy_wanted_features wanted_features[LEGACY_FEATURE_WORD]
+#define=A0legacy_vlan_features =A0 =A0vlan_features[LEGACY_FEATURE_WOR=
D]


So that it will be a matter of -

s/features/legacy_features/
s/hw_features/legacy_hw_features/
s/wanted_features/legacy_wanted_features/
s/vlan_features/legacy_vlan_features/

to start with as a first step. Once this is done, legacy_* can be
changed with respective arrays and modified as per the need. Comments?

--mahesh..