| Message ID | 20230627035839.496399-9-zack@kde.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Fix cursor planes with virtualized drivers | expand |
On Mon, 26 Jun 2023 23:58:39 -0400 Zack Rusin <zack@kde.org> wrote: > From: Zack Rusin <zackr@vmware.com> > > Virtualized drivers place additional restrictions on the cursor plane > which breaks the contract of universal planes. To allow atomic > modesettings with virtualized drivers the clients need to advertise > that they're capable of dealing with those extra restrictions. > > To do that introduce DRM_CLIENT_CAP_VIRTUALIZED_CURSOR_PLANE which > lets DRM know that the client is aware of and capable of dealing with > the extra restrictions on the virtual cursor plane. > > Setting this option to true makes DRM expose the cursor plane on > virtualized drivers. The userspace is expected to set the hotspots > and handle mouse events on that plane. > > Signed-off-by: Zack Rusin <zackr@vmware.com> > Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> > Cc: Maxime Ripard <mripard@kernel.org> > Cc: Thomas Zimmermann <tzimmermann@suse.de> > Cc: David Airlie <airlied@linux.ie> > Cc: Daniel Vetter <daniel@ffwll.ch> > Cc: dri-devel@lists.freedesktop.org > --- > drivers/gpu/drm/drm_ioctl.c | 9 +++++++++ > include/uapi/drm/drm.h | 26 ++++++++++++++++++++++++++ > 2 files changed, 35 insertions(+) > > diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c > index 8e9afe7af19c..6fd17ff14656 100644 > --- a/drivers/gpu/drm/drm_ioctl.c > +++ b/drivers/gpu/drm/drm_ioctl.c > @@ -361,6 +361,15 @@ drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv) > return -EINVAL; > file_priv->writeback_connectors = req->value; > break; > + case DRM_CLIENT_CAP_VIRTUALIZED_CURSOR_PLANE: > + if (!drm_core_check_feature(dev, DRIVER_CURSOR_HOTSPOT)) > + return -EOPNOTSUPP; > + if (!file_priv->atomic) > + return -EINVAL; > + if (req->value > 1) > + return -EINVAL; > + file_priv->supports_virtualized_cursor_plane = req->value; > + break; > default: > return -EINVAL; > } > diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h > index a87bbbbca2d4..057ef2a16d31 100644 > --- a/include/uapi/drm/drm.h > +++ b/include/uapi/drm/drm.h > @@ -836,6 +836,32 @@ struct drm_get_cap { > */ > #define DRM_CLIENT_CAP_WRITEBACK_CONNECTORS 5 > > +/** > + * DRM_CLIENT_CAP_VIRTUALIZED_CURSOR_PLANE > + * > + * Drivers for para-virtualized hardware (e.g. vmwgfx, qxl, virtio and > + * virtualbox) have additional restrictions for cursor planes (thus > + * making cursor planes on those drivers not truly universal,) e.g. > + * they need cursor planes to act like one would expect from a mouse > + * cursor and have correctly set hotspot properties. > + * If this client cap is not set the DRM core will hide cursor plane on > + * those virtualized drivers because not setting it implies that the > + * client is not capable of dealing with those extra restictions. > + * Clients which do set cursor hotspot and treat the cursor plane > + * like a mouse cursor should set this property. > + * The client must enable &DRM_CLIENT_CAP_ATOMIC first. > + * > + * Setting this property on drivers which do not special case > + * cursor planes (i.e. non-virtualized drivers) will return > + * EOPNOTSUPP, which can be used by userspace to gauge > + * requirements of the hardware/drivers they're running on. > + * > + * This capability is always supported for atomic-capable virtualized > + * drivers starting from kernel version 6.5. > + */ > +#define DRM_CLIENT_CAP_VIRTUALIZED_CURSOR_PLANE 6 All this sounds really good! Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com> The only nitpick I can come up with is maybe naming it to DRM_CLIENT_CAP_CURSOR_PLANE_HOTSPOT to distil the essence of the semantics in the name. I find the word "virtualized" having too many possible meanings in this context. In any case, the doc makes it very clear what this is. I think this feature does not need to be limited to virtualized drivers. If your display hardware system implements gaze tracking, it could show a hardware assisted gaze cursor with this. Thanks, pq > + > + > /* DRM_IOCTL_SET_CLIENT_CAP ioctl argument type */ > struct drm_set_client_cap { > __u64 capability;
Zack Rusin <zack@kde.org> writes: > From: Zack Rusin <zackr@vmware.com> > > Virtualized drivers place additional restrictions on the cursor plane > which breaks the contract of universal planes. To allow atomic > modesettings with virtualized drivers the clients need to advertise > that they're capable of dealing with those extra restrictions. > > To do that introduce DRM_CLIENT_CAP_VIRTUALIZED_CURSOR_PLANE which I agree with Pekka that DRM_CLIENT_CAP_CURSOR_PLANE_HOTSPOT is a better name for this capability. I don't have a strong opinion though so I am also OK with the chosen name. Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c index 8e9afe7af19c..6fd17ff14656 100644 --- a/drivers/gpu/drm/drm_ioctl.c +++ b/drivers/gpu/drm/drm_ioctl.c @@ -361,6 +361,15 @@ drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv) return -EINVAL; file_priv->writeback_connectors = req->value; break; + case DRM_CLIENT_CAP_VIRTUALIZED_CURSOR_PLANE: + if (!drm_core_check_feature(dev, DRIVER_CURSOR_HOTSPOT)) + return -EOPNOTSUPP; + if (!file_priv->atomic) + return -EINVAL; + if (req->value > 1) + return -EINVAL; + file_priv->supports_virtualized_cursor_plane = req->value; + break; default: return -EINVAL; } diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h index a87bbbbca2d4..057ef2a16d31 100644 --- a/include/uapi/drm/drm.h +++ b/include/uapi/drm/drm.h @@ -836,6 +836,32 @@ struct drm_get_cap { */ #define DRM_CLIENT_CAP_WRITEBACK_CONNECTORS 5 +/** + * DRM_CLIENT_CAP_VIRTUALIZED_CURSOR_PLANE + * + * Drivers for para-virtualized hardware (e.g. vmwgfx, qxl, virtio and + * virtualbox) have additional restrictions for cursor planes (thus + * making cursor planes on those drivers not truly universal,) e.g. + * they need cursor planes to act like one would expect from a mouse + * cursor and have correctly set hotspot properties. + * If this client cap is not set the DRM core will hide cursor plane on + * those virtualized drivers because not setting it implies that the + * client is not capable of dealing with those extra restictions. + * Clients which do set cursor hotspot and treat the cursor plane + * like a mouse cursor should set this property. + * The client must enable &DRM_CLIENT_CAP_ATOMIC first. + * + * Setting this property on drivers which do not special case + * cursor planes (i.e. non-virtualized drivers) will return + * EOPNOTSUPP, which can be used by userspace to gauge + * requirements of the hardware/drivers they're running on. + * + * This capability is always supported for atomic-capable virtualized + * drivers starting from kernel version 6.5. + */ +#define DRM_CLIENT_CAP_VIRTUALIZED_CURSOR_PLANE 6 + + /* DRM_IOCTL_SET_CLIENT_CAP ioctl argument type */ struct drm_set_client_cap { __u64 capability;