From patchwork Mon Oct 16 14:25:19 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Ser X-Patchwork-Id: 13423482 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D967CCDB483 for ; Mon, 16 Oct 2023 14:25:31 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 97ADB10E1F1; Mon, 16 Oct 2023 14:25:28 +0000 (UTC) Received: from mail-40136.proton.ch (mail-40136.proton.ch [185.70.40.136]) by gabe.freedesktop.org (Postfix) with ESMTPS id 7261810E1F1 for ; Mon, 16 Oct 2023 14:25:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=emersion.fr; s=protonmail2; t=1697466324; x=1697725524; bh=BvSkarwPpohqnKGpiTKQyOw0hW8Fluzd3JA9pYr8vus=; h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: Feedback-ID:From:To:Cc:Date:Subject:Reply-To:Feedback-ID: Message-ID:BIMI-Selector; b=EAICPuVBH132cywYcvoB4ZGHTX0kSjeh7lDhSDwENGpsbW8uN5G365jdWCcsn9o5f 2BzcTfqkec+QEMkVzOY18a9Wy1CrlMMskGN0+2G+AytEWt0x1iRAzZNq1nBeVL/uvU 4i3XXnPLOH56md3s9iGbKpMMlQuEL4h88QQRZQT155SbgtpyEYWZCIoxO3MfQTdgwS Hwu02ePFzzKVR2ZYRtO2PznsJN2VtxAzqHn2ZF94bcRP+SfmbIs47GQbd5OHR4iJQW Ole380fgxENX2mZ/mLzpb7lwwKTqYLYZhezPTLV7WE17CWp5il2sMDtqvpkcaXr+tF Nvq9WSNr1XVaw== Date: Mon, 16 Oct 2023 14:25:19 +0000 To: dri-devel@lists.freedesktop.org From: Simon Ser Subject: [PATCH 2/2] drm: introduce CLOSEFB IOCTL Message-ID: <20231016142510.3109-2-contact@emersion.fr> In-Reply-To: <20231016142510.3109-1-contact@emersion.fr> References: <20231016142510.3109-1-contact@emersion.fr> Feedback-ID: 1358184:user:proton MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Pekka Paalanen , Hans de Goede , Sean Paul , Dennis Filder Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" 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]. [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 Acked-by: Pekka Paalanen Cc: Hans de Goede Cc: Dennis Filder Cc: Daniel Vetter Cc: Rob Clark Cc: Sean Paul --- drivers/gpu/drm/drm_crtc_internal.h | 2 ++ drivers/gpu/drm/drm_framebuffer.c | 19 +++++++++++++++++++ drivers/gpu/drm/drm_ioctl.c | 1 + include/uapi/drm/drm.h | 20 ++++++++++++++++++++ 4 files changed, 42 insertions(+) diff --git a/drivers/gpu/drm/drm_crtc_internal.h b/drivers/gpu/drm/drm_crtc_internal.h index 8556c3b3ff88..6b646e0783be 100644 --- a/drivers/gpu/drm/drm_crtc_internal.h +++ b/drivers/gpu/drm/drm_crtc_internal.h @@ -222,6 +222,8 @@ int drm_mode_addfb2_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv); int drm_mode_rmfb_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv); +int drm_mode_closefb_ioctl(struct drm_device *dev, + void *data, struct drm_file *file_priv); int drm_mode_getfb(struct drm_device *dev, void *data, struct drm_file *file_priv); int drm_mode_getfb2_ioctl(struct drm_device *dev, diff --git a/drivers/gpu/drm/drm_framebuffer.c b/drivers/gpu/drm/drm_framebuffer.c index 62306196808c..78da835c67c6 100644 --- a/drivers/gpu/drm/drm_framebuffer.c +++ b/drivers/gpu/drm/drm_framebuffer.c @@ -482,6 +482,25 @@ int drm_mode_rmfb_ioctl(struct drm_device *dev, return drm_mode_rmfb(dev, *fb_id, file_priv); } +int drm_mode_closefb_ioctl(struct drm_device *dev, + void *data, struct drm_file *file_priv) +{ + uint32_t *fb_id = data; + struct drm_framebuffer *fb; + int ret; + + if (!drm_core_check_feature(dev, DRIVER_MODESET)) + return -EOPNOTSUPP; + + fb = drm_framebuffer_lookup(dev, file_priv, *fb_id); + if (!fb) + return -ENOENT; + + ret = drm_mode_closefb(fb, file_priv); + drm_framebuffer_put(fb); + return ret; +} + /** * drm_mode_getfb - get FB info * @dev: drm device for the ioctl diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c index 77590b0f38fa..44fda68c28ae 100644 --- a/drivers/gpu/drm/drm_ioctl.c +++ b/drivers/gpu/drm/drm_ioctl.c @@ -675,6 +675,7 @@ static const struct drm_ioctl_desc drm_ioctls[] = { DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb_ioctl, 0), + DRM_IOCTL_DEF(DRM_IOCTL_MODE_CLOSEFB, drm_mode_closefb_ioctl, 0), DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER), DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, 0), diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h index 794c1d857677..a9b7dc9da163 100644 --- a/include/uapi/drm/drm.h +++ b/include/uapi/drm/drm.h @@ -1198,6 +1198,26 @@ 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, unsigned int) + /* * Device specific ioctls should only be in their respective headers * The device specific ioctl range is from 0x40 to 0x9f.