From patchwork Mon Mar 24 15:13:53 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Almeida X-Patchwork-Id: 14027484 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 A3E30C3600C for ; Mon, 24 Mar 2025 15:14:45 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id AB11510E3BD; Mon, 24 Mar 2025 15:14:44 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=collabora.com header.i=daniel.almeida@collabora.com header.b="GZsM9Zg5"; dkim-atps=neutral Received: from sender4-pp-f112.zoho.com (sender4-pp-f112.zoho.com [136.143.188.112]) by gabe.freedesktop.org (Postfix) with ESMTPS id A806D10E371 for ; Mon, 24 Mar 2025 15:14:37 +0000 (UTC) ARC-Seal: i=1; a=rsa-sha256; t=1742829269; cv=none; d=zohomail.com; s=zohoarc; b=DYRmkZx9sE5SMUtqUFXomoskrRBYFm5JMsDAWIZo4Ejci7i01WOdacT04at6YteccWNxRns6/H95QfR6VXVpMU7M5WUEBqrBSWIGaxerQUwpx43UVBQ8rRlGR+Z5YfaeCKRQ8uZBIslK7W8GD5Wr/8Hfk5WR0X+NimgTtRseeIA= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1742829269; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:MIME-Version:Message-ID:Subject:Subject:To:To:Message-Id:Reply-To; bh=fHt+ZqVcnPeLawl8u8AoaiJHBPS3Pj33Q76eBWyxJ+s=; b=KZ78gsDm7M2o0QViQ1buJ2pfuQpBJYHqUHMH0WyuawozVRQCZf0cx3hjLhIHi86CmNj5xR5UvYfnxMYftXCRbdQQnpvSgt3tJCVbWaKRGxI65DnsQLWB7ChG/2Kd8PxjsGX5VOlImqJXMOO0cbm8Ud/q26lYjOW+arG7YwFRFKM= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=collabora.com; spf=pass smtp.mailfrom=daniel.almeida@collabora.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1742829269; s=zohomail; d=collabora.com; i=daniel.almeida@collabora.com; h=From:From:Subject:Subject:Date:Date:Message-Id:Message-Id:MIME-Version:Content-Type:Content-Transfer-Encoding:To:To:Cc:Cc:Reply-To; bh=fHt+ZqVcnPeLawl8u8AoaiJHBPS3Pj33Q76eBWyxJ+s=; b=GZsM9Zg54rb5m8k9Cz7SJyU4/2HmbRUF1IHkxJirez16A4oImVoQDumo7KHrvYeq k/6KvoVnhxuHiuE04fFyD2AlMfWfKoKoSph/x0aVFhypeo8q++Ksm6IqiHeSQHmEcoj 6cc/YjawHx2JuvivwRYCMfFGzsskWbmQIAftVG+c= Received: by mx.zohomail.com with SMTPS id 174282926674419.243781813271767; Mon, 24 Mar 2025 08:14:26 -0700 (PDT) From: Daniel Almeida Subject: [PATCH 0/2] Add a Rust GPUVM abstraction Date: Mon, 24 Mar 2025 12:13:53 -0300 Message-Id: <20250324-gpuvm-v1-0-7f8213eebb56@collabora.com> MIME-Version: 1.0 X-B4-Tracking: v=1; b=H4sIALF24WcC/6tWKk4tykwtVrJSqFYqSi3LLM7MzwNyDHUUlJIzE vPSU3UzU4B8JSMDI1MDYyMD3fSC0rJcXSPLFONUA3MjszRjEyWg2oKi1LTMCrA50bG1tQDGoJV YVwAAAA== X-Change-ID: 20250320-gpuvm-29d3e0726f34 To: Miguel Ojeda , Alex Gaynor , Boqun Feng , Gary Guo , =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= , Benno Lossin , Andreas Hindborg , Alice Ryhl , Trevor Gross , Sumit Semwal , =?utf-8?q?Christian_K=C3=B6nig?= , Boris Brezillon Cc: linux-kernel@vger.kernel.org, rust-for-linux@vger.kernel.org, dri-devel@lists.freedesktop.org, Asahi Lina , Daniel Almeida X-Mailer: b4 0.14.2 X-ZohoMailClient: External 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" Changes from v0: This version changes how `LockedGpuVm` operates. The previous code assumed that the interval tree would be protected if all the associated GEM's resvs were locked, but this is completely unrelated. In fact, this initial version only aims to support the core VA range management feature of GPUVM, and not any of the "convenience" functions like "exec_lock()" and friends, so this function was removed accordingly. LockedGpuVm is now produced by a call to GpuVm::lock(). This takes a generic guard type to signal that the driver-specific locks have been acquired in order to protect the VMs tree, and hence its view of the address space. This approach is somewhat similar to CondVar, but also incurs in the same pitfall: it is up to the caller to give meaning to the guard by ensuring that it actually protects against concurrent access to the VM. Maybe this is a good candidate to the upcoming "Pitfall" docs section? Note that LockedGpuVm::obj was removed. I'm not really sure why this field was there in the first place, but callers should indicate the object through the sm_map() and sm_unmap() APIs instead. I am not sure why GpuVm::inner uses UnsafeCell, though. I did not touch this so that we can first discuss whether UnsafeCell is really needed. The docs were also updated. Care was taken to reuse the C documentation as much as possible. Itemized changes: - Rebased on top of nova-drm - Use `srctree` in the docs - Add docs as appropriate and remove #[allow(missing_docs)] - Remove `impl DriverGpuVa for ()`. Drivers can to that themselves, if they want. - Added #[inline] to getters, as Rust cannot inline across crates otherwise (unless this changed recently?) - Exposed `drm_gpuva_op_unmap::keep`. - Removed `pub(super)` from unsafe fns meant to be called from the C code. - Added "# Safety" blocks to the above. - Removed `exec_lock_gem_object()`. - Removed `exec_lock()` - Removed `LockedGpuVm::vm_exec`. This initial version does not support `exec` calls at all. - By the same token, removed `LockedGpuVm::drop()` - Removed `LockedGpuVm::obj`. This object has to be passed explicitly. --- Asahi Lina (2): rust: helpers: Add bindings/wrappers for dma_resv rust: drm: Add GPUVM abstraction rust/bindings/bindings_helper.h | 5 +- rust/helpers/dma-resv.c | 13 + rust/helpers/drm_gpuvm.c | 29 ++ rust/helpers/helpers.c | 2 + rust/kernel/drm/gpuvm.rs | 790 ++++++++++++++++++++++++++++++++++++++++ rust/kernel/drm/mod.rs | 2 + 6 files changed, 840 insertions(+), 1 deletion(-) --- base-commit: e7de41cc4b01dd5500a0c2533c64bdb3f5360567 change-id: 20250320-gpuvm-29d3e0726f34 Best regards,