In message: <[EMAIL PROTECTED]>
Ryan W Smith <[EMAIL PROTECTED]> writes:
: I'm currently working on a project where we're using qemu to trace
: information flow through the operating system. One of the things
: that we'd like to do is trace network data as it flows through the
: operating system. I've been reading through the code, and I've
: gotten a bit lost. I gather that slirp is where data comes and goes
: from the host operating system, but I'm looking for the section of
: code that sends and receives data from the guest operating system. I
: read through the network device code (ne2000.c), and my guess is that
: the inb and outb functions are used to transfer data to the guest,
: but I'm not quite certain how that is done. Is there anything that
: anyone can point me to that would explain the process of getting data
: from the networking device to the guest operating system? Also, is
: there anything that explains the ne2k networking device a little
: more, and could explain what all the registers are and how to use
: them? Thanks in advance for any help you may offer.
Well, the ne2000 has a shared memory area that the packets live in,
and a i/o port area that signals the host O/S what's going on.
I'd suggest reading the FreeBSD if_ed driver for some more information
about the card. From it you'll see that the NE2000 has a DS8390
packet engine that does a DMA directly into the shared memory. The
ds8390 datasheet can be foudn on the network. You may also find good
comments in the Linux ne.c driver:
http://www.gelato.unsw.edu.au/lxr/source/drivers/net/ne.c
Warner
