diff options
| author | Simon Ser <contact@emersion.fr> | 2023-10-20 13:19:45 +0300 |
|---|---|---|
| committer | Simon Ser <contact@emersion.fr> | 2023-10-27 14:47:56 +0300 |
| commit | d208d875667e2a29beeec5d475f4b6b164b632fa (patch) | |
| tree | acecbcfbae15bd4e0edf88ed536ecf4638ae3f61 /include/uapi/drm | |
| parent | 0226ba393eb1a90d63955cc407340c5d506ecacf (diff) | |
| download | linux-d208d875667e2a29beeec5d475f4b6b164b632fa.tar.xz | |
drm: introduce CLOSEFB IOCTL
This new IOCTL allows callers to close a framebuffer without
disabling planes or CRTCs. This takes inspiration from Rob Clark's
unref_fb IOCTL [1] and DRM_MODE_FB_PERSIST [2].
User-space patch for wlroots available at [3]. IGT test available
at [4].
v2: add an extra pad field just in case we want to extend this IOCTL
in the future (Pekka, Sima).
[1]: https://lore.kernel.org/dri-devel/20170509153654.23464-1-robdclark@gmail.com/
[2]: https://lore.kernel.org/dri-devel/20211006151921.312714-1-contact@emersion.fr/
[3]: https://gitlab.freedesktop.org/wlroots/wlroots/-/merge_requests/4394
[4]: https://lists.freedesktop.org/archives/igt-dev/2023-October/063294.html
Signed-off-by: Simon Ser <contact@emersion.fr>
Reviewed-by: Daniel Stone <daniels@collabora.com>
Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Dennis Filder <d.filder@web.de>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20231020101926.145327-2-contact@emersion.fr
Diffstat (limited to 'include/uapi/drm')
| -rw-r--r-- | include/uapi/drm/drm.h | 20 | ||||
| -rw-r--r-- | include/uapi/drm/drm_mode.h | 10 |
2 files changed, 30 insertions, 0 deletions
diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h index de723566c5ae..8662b5aeea0c 100644 --- a/include/uapi/drm/drm.h +++ b/include/uapi/drm/drm.h @@ -1218,6 +1218,26 @@ extern "C" { #define DRM_IOCTL_SYNCOBJ_EVENTFD DRM_IOWR(0xCF, struct drm_syncobj_eventfd) +/** + * DRM_IOCTL_MODE_CLOSEFB - Close a framebuffer. + * + * This closes a framebuffer previously added via ADDFB/ADDFB2. The IOCTL + * argument is a framebuffer object ID. + * + * This IOCTL is similar to &DRM_IOCTL_MODE_RMFB, except it doesn't disable + * planes and CRTCs. As long as the framebuffer is used by a plane, it's kept + * alive. When the plane no longer uses the framebuffer (because the + * framebuffer is replaced with another one, or the plane is disabled), the + * framebuffer is cleaned up. + * + * This is useful to implement flicker-free transitions between two processes. + * + * Depending on the threat model, user-space may want to ensure that the + * framebuffer doesn't expose any sensitive user information: closed + * framebuffers attached to a plane can be read back by the next DRM master. + */ +#define DRM_IOCTL_MODE_CLOSEFB DRM_IOWR(0xD0, struct drm_mode_closefb) + /* * Device specific ioctls should only be in their respective headers * The device specific ioctl range is from 0x40 to 0x9f. diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h index 128d09138ceb..09e7a471ee30 100644 --- a/include/uapi/drm/drm_mode.h +++ b/include/uapi/drm/drm_mode.h @@ -1323,6 +1323,16 @@ struct drm_mode_rect { __s32 y2; }; +/** + * struct drm_mode_closefb + * @fb_id: Framebuffer ID. + * @pad: Must be zero. + */ +struct drm_mode_closefb { + __u32 fb_id; + __u32 pad; +}; + #if defined(__cplusplus) } #endif |