[PATCH v2 0/6] Adds support for ConfigFS to VKMS!

[Brandon Ross Pollack]

Some of these comments have been sitting for a while.  Would it be ok if 
yixie at chromium.org and myself picked these up and did an iteration so we 
could also get 
https://patchwork.kernel.org/project/dri-devel/patch/20230711013148.3155572-1-brpol@chromium.org/ 
submitted?  These will enable a lot of virtual multi display testing in 
linux! :)

On 6/24/23 07:23, Jim Shargo wrote:
> Intro
> =====
>
> At long last, we're back!
>
> This patchset adds basic ConfigFS support to VKMS, allowing users to
> build new DRM devices with user-defined DRM objects and object
> relationships by creating, writing, and symlinking files.
>
> Usageubmitted
> =====
>
> After installing these patches, you can create a VKMS device with two
> displays and a movable overlay like so (this is documented in the
> patches):
>
>    $ modprobe vkms enable_overlay=1 enable_cursor=1 enable_writeback=1
>    $ mkdir -p /config/
>    $ mount -t configfs none /config
>
>    $ export DRM_PLANE_TYPE_PRIMARY=1
>    $ export DRM_PLANE_TYPE_CURSOR=2
>    $ export DRM_PLANE_TYPE_OVERLAY=0
>
>    $ mkdir /config/vkms/test
>
>    $ mkdir /config/vkms/test/planes/primary
>    $ echo $DRM_PLANE_TYPE_PRIMARY > /config/vkms/test/planes/primary/type
>
>    $ mkdir /config/vkms/test/planes/other_primary
>    $ echo $DRM_PLANE_TYPE_PRIMARY > /config/vkms/test/planes/other_primary/type
>
>    $ mkdir /config/vkms/test/planes/cursor
>    $ echo $DRM_PLANE_TYPE_CURSOR > /config/vkms/test/planes/cursor/type
>
>    $ mkdir /config/vkms/test/planes/overlay
>    $ echo $DRM_PLANE_TYPE_OVERLAY > /config/vkms/test/planes/overlay/type
>
>    $ mkdir /config/vkms/test/crtcs/crtc
>    $ mkdir /config/vkms/test/crtcs/crtc_other
>    $ mkdir /config/vkms/test/encoders/encoder
>    $ mkdir /config/vkms/test/connectors/connector
>
>    $ ln -s /config/vkms/test/encoders/encoder /config/vkms/test/connectors/connector/possible_encoders
>    $ ln -s /config/vkms/test/crtcs/crtc /config/vkms/test/encoders/encoder/possible_crtcs/
>    $ ln -s /config/vkms/test/crtcs/crtc /config/vkms/test/planes/primary/possible_crtcs/
>    $ ln -s /config/vkms/test/crtcs/crtc /config/vkms/test/planes/cursor/possible_crtcs/
>    $ ln -s /config/vkms/test/crtcs/crtc /config/vkms/test/planes/overlay/possible_crtcs/
>    $ ln -s /config/vkms/test/crtcs/crtc_other /config/vkms/test/planes/overlay/possible_crtcs/
>    $ ln -s /config/vkms/test/crtcs/crtc_other /config/vkms/test/planes/other_primary/possible_crtcs/
>
>    $ echo 1 > /config/vkms/test/enabled
>
> Changes within core VKMS
> ========================
>
> This introduces a few important changes to the overall structure of
> VKMS:
>
>    - Devices are now memory managed!
>    - Support for multiple CRTCs and other objects has been added
>
> Since v1
> ========
>
>    - Added DRMM memory management to automatically clean up resources
>    - Added a param to disable the default device
>    - Renamed "cards" to "devices" to improve legibility
>    - Added a lock for the configfs setup handler
>    - Moved all the new docs into the relevant .c file
>    - Addressed as many of sean at poorly.run as possible
>
> Testing
> =======
>
>    - New IGT tests (see
>      gitlab.freedesktop.org/jshargo/igt-gpu-tools/-/merge_requests/1)
>    - Existing IGT tests (excluding .*suspend.*, including .*kms_flip.*
>      .*kms_writeback.* .*kms_cursor_crc.*, .*kms_plane.*)
>
> Outro
> =====
>
> I'm excited to share these changes, it's my still my first kernel patch
> and I've been putting a lot of love into these.
>
> Jim Shargo (6):
>    drm/vkms: Back VKMS with DRM memory management instead of static
>      objects
>    drm/vkms: Support multiple DRM objects (crtcs, etc.) per VKMS device
>    drm/vkms: Provide platform data when creating VKMS devices
>    drm/vkms: Add ConfigFS scaffolding to VKMS
>    drm/vkms: Support enabling ConfigFS devices
>    drm/vkms: Add a module param to enable/disable the default device
>
>   Documentation/gpu/vkms.rst            |  17 +-
>   drivers/gpu/drm/Kconfig               |   1 +
>   drivers/gpu/drm/vkms/Makefile         |   1 +
>   drivers/gpu/drm/vkms/vkms_composer.c  |  28 +-
>   drivers/gpu/drm/vkms/vkms_configfs.c  | 657 ++++++++++++++++++++++++++
>   drivers/gpu/drm/vkms/vkms_crtc.c      |  97 ++--
>   drivers/gpu/drm/vkms/vkms_drv.c       | 208 +++++---
>   drivers/gpu/drm/vkms/vkms_drv.h       | 166 +++++--
>   drivers/gpu/drm/vkms/vkms_output.c    | 299 ++++++++++--
>   drivers/gpu/drm/vkms/vkms_plane.c     |  44 +-
>   drivers/gpu/drm/vkms/vkms_writeback.c |  26 +-
>   11 files changed, 1312 insertions(+), 232 deletions(-)
>   create mode 100644 drivers/gpu/drm/vkms/vkms_configfs.c