vfio-e1000

Simple Intel 1GbE network driver implementation using VFIO.

Binding vfio-pci driver

• Before using VFIO, you need to bind vfio-pci driver to the NIC like the following.

% lspci -nn | grep -i Ether
86:00.0 Ethernet controller [0200]: Intel Corporation 82574L Gigabit Network Connection [8086:10d3]
% sudo modprobe vfio-pci
% echo 0000:86:00.0 | sudo tee -a /sys/bus/pci/devices/0000:86:00.0/driver/unbind
% echo 8086 10d3 | sudo tee -a /sys/bus/pci/drivers/vfio-pci/new_id
% sudo chown -R group:user /dev/vfio/66

• You can use vfio-pci-bind

Compile

• gcc -o e1000 e1000.c
  • Use INTx, dump received packets
• gcc -o e1000 e1000.c -DPOLL
  • polling instead of interrupts
• gcc -o e1000 e1000.c -DMSIX -DTXINT -DECHO
  • use MSIX, enable Tx interrupt, echo received packets
• For more detail, see the source

Usage

• ./e1000 <segment:bus:device.function>
  • for example, ./e1000 0000:01:00.0

Note

• If you get out of memory error, probably you need to increase the memlock limits.
  • VFIO automatically lock the DMA memory region so as not to be moved.
  • Check current memlock liimit: prlimit -l
  • Temporary increase the limit: sudo prlimit --memlock=-1 ./e1000 0000:01:00.0
  • To make the configuration permanent, edit /etc/security/limits.conf
• I only tested this with 82574L on Intel CPU.

Requirements

• IOMMU (VT-d for Intel)
  • VFIO supports no IOMMU mode, but this driver currently does not.

Reference

• https://www.kernel.org/doc/Documentation/vfio.txt
• Intel® 82574 GbE Controller Family Datasheet, https://www.intel.ca/content/dam/doc/datasheet/82574l-gbe-controller-datasheet.pdf
• MINIX e1000, https://github.com/Stichting-MINIX-Research-Foundation/minix/tree/master/minix/drivers/net/e1000
• FreeBSD e1000, https://github.com/freebsd/freebsd/tree/master/sys/dev/e1000
• Redox e1000, https://github.com/redox-os/drivers/blob/master/e1000d/
• snabb driver, https://github.com/snabbco/snabb/blob/master/src/apps/intel_mp/intel_mp.lua
  • old version, https://github.com/anttikantee/snabbswitch/blob/master/src/apps/intel/intel.lua

License

MIT