[dpdk-dev] [RFC 0/3] Add mdev (Mediated device) support in DPDK

[Tiwei Bie <tiwei.bie@intel.com>]

Hi everyone,

This is a draft implementation of the mdev (Mediated device [1])
bus support in DPDK. Mdev is a way to virtualize devices in Linux
kernel. Based on the device-api (mdev_type/device_api), there could
be different types of mdev devices (e.g. vfio-pci). In this RFC,
one mdev bus is introduced to scan the mdev devices in the system
and do the probe based on the device-api.

Take the mdev devices whose device-api is "vfio-pci" as an example,
in this RFC, these devices will be probed by a mdev driver provided
by PCI bus, which will plug them to the PCI bus. And they will be
probed with the drivers registered on the PCI bus based on VendorID/
DeviceID/... then.

                     +----------+
                     | mdev bus |
                     +----+-----+
                          |
         +----------------+----+------+------+
         |                     |      |      |
   mdev_vfio_pci               ......
(device-api: vfio-pci)

There are also other ways to add mdev device support in DPDK (e.g.
let PCI bus scan /sys/bus/mdev/devices directly). Comments would be
appreciated!

[1] https://github.com/torvalds/linux/blob/master/Documentation/vfio-mediated-device.txt

Thanks,
Tiwei

Tiwei Bie (3):
  eal: add a helper for reading string from sysfs
  bus/mdev: add mdev bus support
  bus/pci: add mdev support

 config/common_base                        |   5 +
 config/common_linux                       |   1 +
 drivers/bus/Makefile                      |   1 +
 drivers/bus/mdev/Makefile                 |  41 +++
 drivers/bus/mdev/linux/Makefile           |   6 +
 drivers/bus/mdev/linux/mdev.c             | 117 ++++++++
 drivers/bus/mdev/mdev.c                   | 310 ++++++++++++++++++++++
 drivers/bus/mdev/meson.build              |  15 ++
 drivers/bus/mdev/private.h                |  90 +++++++
 drivers/bus/mdev/rte_bus_mdev.h           | 141 ++++++++++
 drivers/bus/mdev/rte_bus_mdev_version.map |  12 +
 drivers/bus/meson.build                   |   2 +-
 drivers/bus/pci/Makefile                  |   3 +
 drivers/bus/pci/linux/Makefile            |   4 +
 drivers/bus/pci/linux/pci_vfio.c          |  35 ++-
 drivers/bus/pci/linux/pci_vfio_mdev.c     | 305 +++++++++++++++++++++
 drivers/bus/pci/meson.build               |   4 +-
 drivers/bus/pci/pci_common.c              |  17 +-
 drivers/bus/pci/private.h                 |   9 +
 drivers/bus/pci/rte_bus_pci.h             |  11 +-
 lib/librte_eal/common/eal_filesystem.h    |   7 +
 lib/librte_eal/freebsd/eal/eal.c          |  22 ++
 lib/librte_eal/linux/eal/eal.c            |  22 ++
 lib/librte_eal/rte_eal_version.map        |   1 +
 mk/rte.app.mk                             |   1 +
 25 files changed, 1163 insertions(+), 19 deletions(-)
 create mode 100644 drivers/bus/mdev/Makefile
 create mode 100644 drivers/bus/mdev/linux/Makefile
 create mode 100644 drivers/bus/mdev/linux/mdev.c
 create mode 100644 drivers/bus/mdev/mdev.c
 create mode 100644 drivers/bus/mdev/meson.build
 create mode 100644 drivers/bus/mdev/private.h
 create mode 100644 drivers/bus/mdev/rte_bus_mdev.h
 create mode 100644 drivers/bus/mdev/rte_bus_mdev_version.map
 create mode 100644 drivers/bus/pci/linux/pci_vfio_mdev.c

-- 
2.17.1