From: Tomasz Figa <tf...@chromium.org> There is no particular reason to prevent userspace for using this IOCTL, considering that it already has access to other, platform-specific IOCTLs. This patch makes is possible to have the same userspace code work regardless on the underlying platform, which significantly simplifies the stack.
Signed-off-by: Tomasz Figa <tf...@chromium.org> Reviewed-by: Zach Reizner <za...@chromium.org> Signed-off-by: Nicolas Norvez <nor...@chromium.org> Reviewed-by: Tomasz Figa <tf...@chromium.org> Signed-off-by: Robert Foss <robert.f...@collabora.com> --- I've been looking into enabling a kms_swrast based driver for mesa on the Android platform[1]. But have come up against the issue of dumb buffer related ioctls below not being flagged with DRM_RENDER_ALLOW. DRM_IOCTL_MODE_CREATE_DUMB DRM_IOCTL_MODE_MAP_DUMB To be more precise, I've been seeing a failure due to DRM_IOCTL_MODE_MAP_DUMB not being allowed for /dev/dri/renderD* nodes, and used in mesa kms_sw_displaytarget_map(). As I understand it the DRM_RENDER_ALLOW flag being unset is a very intentional restriction placed on dumb buffers in order to minimize its use. But as far as alternative solutions for software renderers there seems to only be VGEM and mmap()-ing DMABUFs. While it would be convenient from the point of view of software renderers if dumb buffers had more promiscuous permissions, it may be a hard sell upstream. If dumb buffers aren't the way forward, what is? VGEM? Or are there any other preferable ways? [1] https://patchwork.freedesktop.org/series/45966/ drivers/gpu/drm/drm_ioctl.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c index 0d4cfb232576..ef716246baf6 100644 --- a/drivers/gpu/drm/drm_ioctl.c +++ b/drivers/gpu/drm/drm_ioctl.c @@ -642,8 +642,8 @@ static const struct drm_ioctl_desc drm_ioctls[] = { DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb, DRM_UNLOCKED), DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER|DRM_UNLOCKED), DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER|DRM_UNLOCKED), - DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, DRM_UNLOCKED), - DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, DRM_UNLOCKED), + DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, DRM_UNLOCKED|DRM_RENDER_ALLOW), + DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, DRM_UNLOCKED|DRM_RENDER_ALLOW), DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, DRM_UNLOCKED), DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, DRM_UNLOCKED), DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER|DRM_UNLOCKED), -- 2.17.1 _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
