[libvirt] [PATCH for-4.0 v4 0/2] virtio: Provide version-specific variants of virtio PCI devices

[Eduardo Habkost]

Friendly ping.  3.1.0 is tagged now, so there's anything else
blocking this series?


On Wed, Dec 05, 2018 at 05:57:02PM -0200, Eduardo Habkost wrote:
> Existing modern-only device types are not being touched by v3, as
> they don't need separate variants.  However, I plan to implement
> separate cleanups in the code that calls virtio_pci_force_virtio_1(),
> first, and then propose additional changes (e.g. deprecating
> disable-legacy and disable-modern in those device types).
> 
> Changes v3 -> v4:
> * Trivial comment fixes (Cornelia Huck)
> * Test code update (Caio Carrara)
> 
> Changes v2 -> v3:
> * Split into two separate patches (type registration helper
>   and introduction of new types)
> * Rewrote virtio_pci_types_register() completely:
>   * Replaced magic generation of type names with explicit fields in
>     VirtioPCIDeviceTypeInfo
>   * Removed modern_only field (not necessary anymore)
>   * Don't register a separate base type unless necessary
> 
> Changes v1 -> v2:
> * Removed *-0.9 devices.  Nobody will want to use them, if
>   transitional devices work with legacy drivers
>   (Gerd Hoffmann, Michael S. Tsirkin)
> * Drop virtio version from name: rename -1.0-transitional to
>   -transitional (Michael S. Tsirkin)
> * Renamed -1.0 to -non-transitional
> * Don't add any extra variants to modern-only device types
>   (they don't need it)
> * Fix typo on TYPE_VIRTIO_INPUT_HOST_PCI (crash reported by
>   Cornelia Huck)
> * No need to change cast macros for modern-only devices
> * Rename virtio_register_types() to virtio_pci_types_register()
> 
> Original patch description:
> 
> Many of the current virtio-*-pci device types actually represent
> 3 different types of devices:
> * virtio 1.0 non-transitional devices
> * virtio 1.0 transitional devices
> * virtio 0.9 ("legacy device" in virtio 1.0 terminology)
> 
> That would be just an annoyance if it didn't break our device/bus
> compatibility QMP interfaces.  With this multi-purpose device
> type, there's no way to tell management software that
> transitional devices and legacy devices require a Conventional
> PCI bus.
> 
> The multi-purpose device types would also prevent us from telling
> management software what's the PCI vendor/device ID for them,
> because their PCI IDs change at runtime depending on the bus
> where they were plugged.
> 
> This patch adds separate device types for each of those virtio
> device flavors:
> 
> * virtio-*-pci: the existing multi-purpose device types
> * virtio-*-pci-transitional: virtio-1.0 device supporting legacy drivers
> * virtio-*-pci-non-transitional: modern-only
> 
> Reference to previous discussion that originated this idea:
>   https://www.mail-archive.com/qemu-devel@nongnu.org/msg558389.html
> 
> Eduardo Habkost (2):
>   virtio: Helper for registering virtio device types
>   virtio: Provide version-specific variants of virtio PCI devices
> 
>  hw/virtio/virtio-pci.h             |  78 +++++++--
>  hw/display/virtio-gpu-pci.c        |   7 +-
>  hw/display/virtio-vga.c            |   7 +-
>  hw/virtio/virtio-crypto-pci.c      |   7 +-
>  hw/virtio/virtio-pci.c             | 267 ++++++++++++++++++++++-------
>  tests/acceptance/virtio_version.py | 176 +++++++++++++++++++
>  6 files changed, 452 insertions(+), 90 deletions(-)
>  create mode 100644 tests/acceptance/virtio_version.py
> 
> -- 
> 2.18.0.rc1.1.g3f1ff2140
> 

-- 
Eduardo