From patchwork Mon Sep 30 23:10:06 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lyude Paul X-Patchwork-Id: 13817276 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 C93F3CEB2CB for ; Mon, 30 Sep 2024 23:40:32 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 5D3C010E5A6; Mon, 30 Sep 2024 23:40:32 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.b="daFccErm"; dkim-atps=neutral Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id F054710E5A2 for ; Mon, 30 Sep 2024 23:40:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1727739627; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Ks/AeHTgPHpVhwmTJF1Of6G8oz5pXr9wZPJOSOab2EM=; b=daFccErm2uPDhJwTn8HeF6oLx0Fmxw8kO1AzHkdeIF0bYG4nJqe3PHsr2LpWn7LWSXKd5m Ap7lrMTnuPUAq3yTPPueX/dgI7nN2qx4YH9PPb9YDOZHg2gPdPGlGDsBDxvIkhaY67wih2 tCg+omBPsBK+s3Szp+0iWCO8iqzcr5E= Received: from mx-prod-mc-02.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-351-ZiOOdnYzM3yS3u0JqSaZCg-1; Mon, 30 Sep 2024 19:40:24 -0400 X-MC-Unique: ZiOOdnYzM3yS3u0JqSaZCg-1 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (unknown [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-02.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 2DAD2195395A; Mon, 30 Sep 2024 23:40:20 +0000 (UTC) Received: from chopper.redhat.com (unknown [10.22.32.36]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 16F4A3003DEC; Mon, 30 Sep 2024 23:40:15 +0000 (UTC) From: Lyude Paul To: dri-devel@lists.freedesktop.org, rust-for-linux@vger.kernel.org Cc: Asahi Lina , Danilo Krummrich , mcanal@igalia.com, airlied@redhat.com, zhiw@nvidia.com, cjia@nvidia.com, jhubbard@nvidia.com, Miguel Ojeda , Alex Gaynor , Wedson Almeida Filho , Boqun Feng , Gary Guo , =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= , Benno Lossin , Andreas Hindborg , Alice Ryhl , Trevor Gross , linux-kernel@vger.kernel.org (open list) Subject: [WIP RFC v2 23/35] rust: drm/kms: Add DriverPlane::atomic_check() Date: Mon, 30 Sep 2024 19:10:06 -0400 Message-ID: <20240930233257.1189730-24-lyude@redhat.com> In-Reply-To: <20240930233257.1189730-1-lyude@redhat.com> References: <20240930233257.1189730-1-lyude@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 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: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Optional trait method for implementing a plane's atomic_check(). Signed-off-by: Lyude Paul --- rust/kernel/drm/kms/plane.rs | 41 +++++++++++++++++++++++++++++++++++- 1 file changed, 40 insertions(+), 1 deletion(-) diff --git a/rust/kernel/drm/kms/plane.rs b/rust/kernel/drm/kms/plane.rs index 506ed5ced1270..04f1bdfbb1ea2 100644 --- a/rust/kernel/drm/kms/plane.rs +++ b/rust/kernel/drm/kms/plane.rs @@ -74,7 +74,7 @@ pub trait DriverPlane: Send + Sync + Sized { cleanup_fb: None, begin_fb_access: None, // TODO: someday? end_fb_access: None, // TODO: someday? - atomic_check: None, + atomic_check: if Self::HAS_ATOMIC_CHECK { Some(atomic_check_callback::) } else { None }, atomic_update: if Self::HAS_ATOMIC_UPDATE { Some(atomic_update_callback::) } else { None }, atomic_enable: None, // TODO atomic_disable: None, // TODO @@ -118,6 +118,21 @@ fn atomic_update( ) { build_error::build_error("This should not be reachable") } + + /// The optional [`drm_plane_helper_funcs.atomic_check`] hook for this plane. + /// + /// Drivers may use this to customize the atomic check phase of their [`Plane`] objects. The + /// result of this function determines whether the atomic check passed or failed. + /// + /// [`drm_plane_helper_funcs.atomic_check`]: srctree/include/drm/drm_modeset_helper_vtables.h + fn atomic_check( + plane: &Plane, + new_state: BorrowedPlaneState<'_, PlaneState>, + old_state: &PlaneState, + state: &AtomicStateComposer + ) -> Result { + build_error::build_error("This should not be reachable") + } } /// The generated C vtable for a [`DriverPlane`]. @@ -794,3 +809,27 @@ fn deref_mut(&mut self) -> &mut Self::Target { T::atomic_update(plane, new_state, old_state, &state); } + +unsafe extern "C" fn atomic_check_callback( + plane: *mut bindings::drm_plane, + state: *mut bindings::drm_atomic_state, +) -> i32 { + // SAFETY: + // * We're guaranteed `plane` is of type `Plane` via type invariants. + // * We're guaranteed by DRM that `plane` is pointing to a valid initialized state. + let plane = unsafe { Plane::from_raw(plane) }; + + // SAFETY: We're guaranteed by DRM that `state` points to a valid instance of `drm_atomic_state` + let state = ManuallyDrop::new(unsafe { + AtomicStateComposer::::new(NonNull::new_unchecked(state)) + }); + + // SAFETY: We're guaranteed by DRM that both the old and new atomic state are present within + // this `drm_atomic_state` + let (old_state, new_state) = unsafe {( + state.get_old_plane_state(plane).unwrap_unchecked(), + state.get_new_plane_state(plane).unwrap_unchecked(), + )}; + + from_result(|| T::atomic_check(plane, new_state, old_state, &state).map(|_| 0)) +}