network interface cards native vlans support in linux kernel?

network interface cards native vlans support in linux kernel?

[Andrius Kasparavicius]

hello, as far as i know, currently there is no native vlan support in
network device drivers. I mean, always need patching MTU.. add 4 bytes..
:-(

is there any problems to include full vlans support?


Andrius

Re: network interface cards native vlans support in linux kernel?

[Jeff Garzik]

On Wed, Jul 09, 2003 at 06:19:51PM +0300, Andrius Kasparavicius wrote:
> hello, as far as i know, currently there is no native vlan support in
> network device drivers. I mean, always need patching MTU.. add 4 bytes..
> :-(
> 
> is there any problems to include full vlans support?

Native VLAN support has been in the kernel for a while.

A few drivers still need patching, and unfortunately the VLAN driver
patches floating around all need cleaning up.

	Jeff

Re: network interface cards native vlans support in linux kernel?

[Rask Ingemann Lambertsen]

On Wed, 9 Jul 2003 11:28:15 -0400, Jeff Garzik wrote
> On Wed, Jul 09, 2003 at 06:19:51PM +0300, Andrius Kasparavicius wrote:
> > hello, as far as i know, currently there is no native vlan support in
> > network device drivers. I mean, always need patching MTU.. add 4 bytes..
[cut]
> A few drivers still need patching, and unfortunately the VLAN driver
> patches floating around all need cleaning up.

What does a network device driver need to do to ensure VLAN compatibility? Is 
it as simple as allocating buffer space for MTU + 4 bytes or is there more to 
it than that?

-- 
Regards,
Rask Ingemann Lambertsen

Re: network interface cards native vlans support in linux kernel?

[Rask Ingemann Lambertsen]

On Wed, Jul 09, 2003 at 11:28:15AM -0400, Jeff Garzik wrote:
> On Wed, Jul 09, 2003 at 06:19:51PM +0300, Andrius Kasparavicius wrote:
> > hello, as far as i know, currently there is no native vlan support in
> > network device drivers. I mean, always need patching MTU.. add 4 bytes..
> > 
> > is there any problems to include full vlans support?
> 
> Native VLAN support has been in the kernel for a while.
> 
> A few drivers still need patching, and unfortunately the VLAN driver
> patches floating around all need cleaning up.

What does a driver need to do to make sure it can handle vlan frames? Is it
enought to be prepared to handle frames of size dev->mtu+4? How do I know 4
bytes will be enough tomorrow when someone introduces VLAN2 with a 64-bit tag?
Checking for CONFIG_VLAN is of no use, right?

-- 
Regards,
Rask Ingemann Lambertsen

Re: network interface cards native vlans support in linux kernel?

[Ben Greear]

Rask Ingemann Lambertsen wrote:
> On Wed, Jul 09, 2003 at 11:28:15AM -0400, Jeff Garzik wrote:
> 
>>On Wed, Jul 09, 2003 at 06:19:51PM +0300, Andrius Kasparavicius wrote:
>>
>>>hello, as far as i know, currently there is no native vlan support in
>>>network device drivers. I mean, always need patching MTU.. add 4 bytes..
>>>
>>>is there any problems to include full vlans support?
>>
>>Native VLAN support has been in the kernel for a while.
>>
>>A few drivers still need patching, and unfortunately the VLAN driver
>>patches floating around all need cleaning up.
> 
> 
> What does a driver need to do to make sure it can handle vlan frames? Is it
> enought to be prepared to handle frames of size dev->mtu+4? How do I know 4
> bytes will be enough tomorrow when someone introduces VLAN2 with a 64-bit tag?
> Checking for CONFIG_VLAN is of no use, right?

It needs to be able to handle 1518 bytes (+crc), send and receive.  I'd
suggest using the Intel e100 or e1000, as they both support VLANs just fine.
Most other GigE nics work too.

Apply the patches in the VLAN howto if you need another NIC that needs
patching.  There seems to be zero motivation by 100bt driver authors to
add VLAN support to the drivers that still need it...

Thanks,
Ben


-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com

Re: network interface cards native vlans support in linux kernel?

[Rask Ingemann Lambertsen]

On Wed, Oct 22, 2003 at 10:01:49AM -0700, Ben Greear wrote:
> Rask Ingemann Lambertsen wrote:
> > 
> > What does a driver need to do to make sure it can handle vlan frames? Is it
> > enought to be prepared to handle frames of size dev->mtu+4? How do I know 4
> > bytes will be enough tomorrow when someone introduces VLAN2 with a 64-bit tag?
> > Checking for CONFIG_VLAN is of no use, right?
> 
> It needs to be able to handle 1518 bytes (+crc), send and receive.  I'd
> suggest using the Intel e100 or e1000, as they both support VLANs just fine.
> Most other GigE nics work too.

I was thinking about what to do as a driver *writer* rather than as a driver
*user*.

#include <linux/if_vlan.h>

and allocating buffers of (dev->mtu + VLAN_ETH_HLEN) bytes. Some chips, such
as the Tulip series, need an extra 4 bytes for the CRC when receiving.

-- 
Regards,
Rask Ingemann Lambertsen

Re: network interface cards native vlans support in linux kernel?

[Ben Greear]

Andrius Kasparavicius wrote:
> hello, as far as i know, currently there is no native vlan support in
> network device drivers. I mean, always need patching MTU.. add 4 bytes..
> :-(
> 
> is there any problems to include full vlans support?

Intel's e100 driver (and all NICs supported by it) support vlans
fine, as do most of the GigE NICs.  Tulip does not, last I hear, though
a work-around patch has been around forever.  Realtek worked at one time,
not sure about now though...

Ben


> 
> 
> Andrius
> 


-- 
Ben Greear <greearb@candelatech.com>       <Ben_Greear AT excite.com>
President of Candela Technologies Inc      http://www.candelatech.com
ScryMUD:  http://scry.wanfear.com     http://scry.wanfear.com/~greear

Re: network interface cards native vlans support in linux kernel?

[Andrius Kasparavicius]

is there a clear list of which cards "works without patch", which
"need patches/mtu changes" and which "never seen working"?

Andrius

On Wed, 9 Jul 2003, Ben Greear wrote:

> Andrius Kasparavicius wrote:
> > hello, as far as i know, currently there is no native vlan support in
> > network device drivers. I mean, always need patching MTU.. add 4 bytes..
> > :-(
> >
> > is there any problems to include full vlans support?
>
> Intel's e100 driver (and all NICs supported by it) support vlans
> fine, as do most of the GigE NICs.  Tulip does not, last I hear, though
> a work-around patch has been around forever.  Realtek worked at one time,
> not sure about now though...

Re: network interface cards native vlans support in linux kernel?

[Andrius Kasparavicius]

on vanilla linux kernel, eepro doesn't work, and with 1496 mtu, 8139too
works with any mtu (and 1500).

which is recommended to use, e100 or eepro100?

Andrius.

On Wed, 9 Jul 2003, Ben Greear wrote:

> > is there any problems to include full vlans support?
>
> Intel's e100 driver (and all NICs supported by it) support vlans
> fine, as do most of the GigE NICs.  Tulip does not, last I hear, though
> a work-around patch has been around forever.  Realtek worked at one time,
> not sure about now though...

Re: network interface cards native vlans support in linux kernel?

[Ben Greear]

Andrius Kasparavicius wrote:
> on vanilla linux kernel, eepro doesn't work, and with 1496 mtu, 8139too
> works with any mtu (and 1500).
> 
> which is recommended to use, e100 or eepro100?

As I mentioned, the e100 (intel's driver) is the one I recommend.

eepro100 does not seem to be updated in the kernel anymore, though if you go figure
out how to install Becker's drivers, he may have it working with vlans
by now.

Ben

> 
> Andrius.
> 
> On Wed, 9 Jul 2003, Ben Greear wrote:
> 
> 
>>>is there any problems to include full vlans support?
>>
>>Intel's e100 driver (and all NICs supported by it) support vlans
>>fine, as do most of the GigE NICs.  Tulip does not, last I hear, though
>>a work-around patch has been around forever.  Realtek worked at one time,
>>not sure about now though...
> 
> 


-- 
Ben Greear <greearb@candelatech.com>       <Ben_Greear AT excite.com>
President of Candela Technologies Inc      http://www.candelatech.com
ScryMUD:  http://scry.wanfear.com     http://scry.wanfear.com/~greear

Re: network interface cards native vlans support in linux kernel?

[Jeff Garzik]

On Fri, Jul 11, 2003 at 10:11:57AM -0700, Ben Greear wrote:
> eepro100 does not seem to be updated in the kernel anymore, though if you 
> go figure
> out how to install Becker's drivers, he may have it working with vlans
> by now.

I won't say for sure, but I'm fairly certain he does.  Most of his
drivers got a "slightly larger than normal MTU" pass-over a while ago.

I objected to the eepro100 patch, because all it did was change one
magic number to another, in the configuration data.  I had absolutely no
basis for evaluation other than "I hope it works", so it was rejected.

If someone wants to look at his eepro100 and merge in new changes (vlan
or otherwise), that'd be great.  His tulip MTU (aka vlan) changes also
want pulling into mainline kernel, since his changes are _much_ better
than the tulip vlan patch floating around.

	Jeff

Re: network interface cards native vlans support in linux kernel?

[Ben Greear]

Jeff Garzik wrote:
> On Fri, Jul 11, 2003 at 10:11:57AM -0700, Ben Greear wrote:
> 
>>eepro100 does not seem to be updated in the kernel anymore, though if you 
>>go figure
>>out how to install Becker's drivers, he may have it working with vlans
>>by now.
> 
> 
> I won't say for sure, but I'm fairly certain he does.  Most of his
> drivers got a "slightly larger than normal MTU" pass-over a while ago.
> 
> I objected to the eepro100 patch, because all it did was change one
> magic number to another, in the configuration data.  I had absolutely no
> basis for evaluation other than "I hope it works", so it was rejected.
> 
> If someone wants to look at his eepro100 and merge in new changes (vlan
> or otherwise), that'd be great.  His tulip MTU (aka vlan) changes also
> want pulling into mainline kernel, since his changes are _much_ better
> than the tulip vlan patch floating around.

It is beyond me to do this merge at this time, but if someone else can
do it that would be great.  I can also do some testing of the tulip
merge, at least..as I have loads of 4-port nics lying around.

Ben

> 
> 	Jeff
> 
> 


-- 
Ben Greear <greearb@candelatech.com>       <Ben_Greear AT excite.com>
President of Candela Technologies Inc      http://www.candelatech.com
ScryMUD:  http://scry.wanfear.com     http://scry.wanfear.com/~greear

RE: network interface cards native vlans support in linux kernel?

[Hen, Shmulik]

Do you mean "native" as in hardware acceleration offloading?
If that's the case than the 8021q vlan module handshakes with the device driver to check for support and that's it. No need to do any settings on the device. In case there is no offloading support, the vlan module will take care of all stripping/inserting of the vlan tag into place.
On the other hand, if the device cannot handle 1504 byte packets, it defines itself as "vlan challenged" and you can't use vlan on it at all.


-- 
| Shmulik Hen                             |
| Israel Design Center (Jerusalem)        |
| LAN Access Division                     |
| Intel Communications Group, Intel corp. |


> -----Original Message-----
> From: Andrius Kasparavicius [mailto:andrius@andrius.org]
> Sent: Wednesday, July 09, 2003 6:20 PM
> To: netdev@oss.sgi.com
> Subject: network interface cards native vlans support in linux kernel?
> 
> 
> 
> hello, as far as i know, currently there is no native vlan support in
> network device drivers. I mean, always need patching MTU.. 
> add 4 bytes..
> :-(
> 
> is there any problems to include full vlans support?
> 
> 
> Andrius
> 
> 

Re: network interface cards native vlans support in linux kernel?

[Ben Greear]

Hen, Shmulik wrote:
> Do you mean "native" as in hardware acceleration offloading?
> If that's the case than the 8021q vlan module handshakes with the device driver to check for support and that's it. No need to do any settings on the device. In case there is no offloading support, the vlan module will take care of all stripping/inserting of the vlan tag into place.
> On the other hand, if the device cannot handle 1504 byte packets, it defines itself as "vlan challenged" and you can't use vlan on it at all.

Even challenged ones can work if you set your MTU (and all peer MTUs) to 4 less than normal,
ie 1496.

Ben

> 
> 


-- 
Ben Greear <greearb@candelatech.com>       <Ben_Greear AT excite.com>
President of Candela Technologies Inc      http://www.candelatech.com
ScryMUD:  http://scry.wanfear.com     http://scry.wanfear.com/~greear