Re: [PATCH][RFC/v1][11/12] Add InfiniBand Documentation files

Re: [PATCH][RFC/v1][11/12] Add InfiniBand Documentation files

[Christoph Hellwig]

> +  When the IPoIB driver is loaded, it creates one interface for each
> +  port using the P_Key at index 0.  To create an interface with a
> +  different P_Key, write the desired P_Key into the main interface's
> +  /sys/class/net/<intf name>/create_child file.  For example:
> +
> +    echo 0x8001 > /sys/class/net/ib0/create_child
> +
> +  This will create an interface named ib0.8001 with P_Key 0x8001.  To
> +  remove a subinterface, use the "delete_child" file:
> +
> +    echo 0x8001 > /sys/class/net/ib0/delete_child
> +
> +  The P_Key for any interface is given by the "pkey" file, and the
> +  main interface for a subinterface is in "parent."

Any reason this doesn't use an interface similar to the normal vlan code?

And what is a P_Key?

Re: [PATCH][RFC/v1][11/12] Add InfiniBand Documentation files

[Roland Dreier]

    Christoph> Any reason this doesn't use an interface similar to the
    Christoph> normal vlan code?

The normal vlan code uses an ioctl().  I thought a simple sysfs
interface would be more palatable than a new socket ioctl.

    Christoph> And what is a P_Key?

It is a 16-bit identifier carried by IB packets that says which
partition the packet is in.  End ports have P_Key tables that list
which partitions they are members of (a port can be a member of one or
more partitions, and can only receive packets from that partition).

 - Roland

Re: Re: [PATCH][RFC/v1][11/12] Add InfiniBand Documentation files

[Eric W. Biederman]

Christoph Hellwig <hch@infradead.org> writes:

> > +  When the IPoIB driver is loaded, it creates one interface for each
> > +  port using the P_Key at index 0.  To create an interface with a
> > +  different P_Key, write the desired P_Key into the main interface's
> > +  /sys/class/net/<intf name>/create_child file.  For example:
> > +
> > +    echo 0x8001 > /sys/class/net/ib0/create_child
> > +
> > +  This will create an interface named ib0.8001 with P_Key 0x8001.  To
> > +  remove a subinterface, use the "delete_child" file:
> > +
> > +    echo 0x8001 > /sys/class/net/ib0/delete_child
> > +
> > +  The P_Key for any interface is given by the "pkey" file, and the
> > +  main interface for a subinterface is in "parent."
> 
> Any reason this doesn't use an interface similar to the normal vlan code?
> 
> And what is a P_Key?

IB version of a vlan identifier.

Eric