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* question about ethtool bits?
@ 2014-11-10 20:47 Jesse Brandeburg
  2014-11-11 18:12 ` Ben Hutchings
  0 siblings, 1 reply; 2+ messages in thread
From: Jesse Brandeburg @ 2014-11-10 20:47 UTC (permalink / raw)
  To: netdev; +Cc: jesse.brandeburg, ben

Ben et al,

So, I was just looking at adding some more types/speeds to
ethtool.h and noticed we are about out of bits in ecmd->advertising
(and others), which are declared u32.

We currently have room for one more type (bit 31) and then all 32 bits
will be full.

Previous solutions have involved adding a new struct member to the end
of ecmd and friends and calling it u32 advertising2 or something.
Another option could be adding a u64, but there may be not fun results
of doing so.

...
#define SUPPORTED_56000baseSR4_Full     (1 << 29)
#define SUPPORTED_56000baseLR4_Full     (1 << 30)

...
#define ADVERTISED_56000baseSR4_Full    (1 << 29)
#define ADVERTISED_56000baseLR4_Full    (1 << 30)

in the case of speed there is already a speed_hi, so that gets us 32
bits of speed expressed in Mb/s

These fast networks create so many problems ;-)

There are two u32's reserved at the end of ethtool_cmd.

Suggestions?

^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: question about ethtool bits?
  2014-11-10 20:47 question about ethtool bits? Jesse Brandeburg
@ 2014-11-11 18:12 ` Ben Hutchings
  0 siblings, 0 replies; 2+ messages in thread
From: Ben Hutchings @ 2014-11-11 18:12 UTC (permalink / raw)
  To: Jesse Brandeburg; +Cc: netdev

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On Mon, 2014-11-10 at 12:47 -0800, Jesse Brandeburg wrote:
> Ben et al,
> 
> So, I was just looking at adding some more types/speeds to
> ethtool.h and noticed we are about out of bits in ecmd->advertising
> (and others), which are declared u32.
> 
> We currently have room for one more type (bit 31) and then all 32 bits
> will be full.

Right, I've been seeing this coming for a while.

[...]
> There are two u32's reserved at the end of ethtool_cmd.
> 
> Suggestions?

Any extension needs to be applied to all of advertising, supported and
lp_advertising.  So we could take 6 of the 8 reserved bytes and extend
them all by 16 bits.

Whoever does this should add getter/setter functions, as has been done
with the extension of speed.

Ben.

-- 
Ben Hutchings
Experience is directly proportional to the value of equipment destroyed.
                                                         - Carolyn Scheppner

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^ permalink raw reply	[flat|nested] 2+ messages in thread

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2014-11-10 20:47 question about ethtool bits? Jesse Brandeburg
2014-11-11 18:12 ` Ben Hutchings

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