From mboxrd@z Thu Jan 1 00:00:00 1970 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 34D43CA601F for ; Fri, 9 Oct 2026 18:45:00 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 8A4E110EB0A; Fri, 9 Oct 2026 18:44:59 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="HvNJBZy9"; dkim-atps=neutral Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by gabe.freedesktop.org (Postfix) with ESMTPS id CE81910EB0A for ; Fri, 9 Oct 2026 18:44:58 +0000 (UTC) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 9D093407BA; Fri, 9 Oct 2026 18:44:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2E99B1F000FF; Fri, 9 Oct 2026 18:44:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1791571498; bh=ocrMeNkMQZu7lUW0ZX/nXGH/6NYNDpKamVvMXgsOpXg=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=HvNJBZy9Tsu7oES9CdsfR4f/4C+IE4xqTb5dLbuMSUyzbZsJ/yjMXR+167f3p//XP ob9okM/QutTRXss9bRhSy32e9t+A72Lx1PrRuFf2/GmmRAXiVDVbwzemFvMgRSZxYa mGBdpo12ahOey7dmJZEFs/eqKDPFLTw8kz22QIdmMIpU+qXV5ZLU0U9IUSkRL5i3rL OIqQh4UappTglas5pgF9N8JI7YpuUHe0ZFJNh7EvC7+IM75vMMXflYmgSLcwMErzNk 4EiUwDS9kMlOCoyBbclPjMXyO/PYSmG2FK5aCTN1dnk9a11R8DFOwhl0lX7LvS5qgh DL5Mh9PLzrdVQ== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v5 17/38] scsi: sg: convert mmap hook to mmap_prepare and rework To: =?utf-8?b?TG9yZW56byBTdG9ha2VzIChBUk0p?= Cc: bpf@vger.kernel.org, kvmarm@lists.linux.dev, "Vasily Gorbik" , linux-perf-users@vger.kernel.org, kvm@vger.kernel.org, linux-s390@vger.kernel.org, linux-usb@vger.kernel.org, "Marc Zyngier" , linux-rdma@vger.kernel.org, selinux@vger.kernel.org, "Heiko Carstens" , dri-devel@lists.freedesktop.org, "Oliver Upton" , "Christian Borntraeger" , linux-trace-kernel@vger.kernel.org, "Alexander Gordeev" , linux-scsi@vger.kernel.org In-Reply-To: <20261009-b4-mmap-prepare-vma-flag-sanify-v5-17-923b70125b1e@kernel.org> References: <20261009-b4-mmap-prepare-vma-flag-sanify-v5-0-923b70125b1e@kernel.org> <20261009-b4-mmap-prepare-vma-flag-sanify-v5-17-923b70125b1e@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Fri, 09 Oct 2026 18:44:56 +0000 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: , Reply-To: sashiko-reviews@lists.linux.dev Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" > Move from the deprecated mmap hook to the new mmap_prepare hook. >=20 > We are mapping kernel pages here, so use the discontiguous kernel mapping > mmap action to do so. >=20 > Unwind the rather confusing loop and instead map as many pages as we can = at > one time. >=20 > Note that we do not need to pay attention to rsv_schp->k_use_sg here, as > the pages are populated for the length of the buffer at > rsv_schp->page_order granularity as compound pages. >=20 > The discontiguous kernel page mapping logic handles the compound pages for > us. >=20 > sfp->mmap_called keeps the buffer stable for us. As before it is never > cleared, so a failed mmap also leaves it set. >=20 > We also remove some useless vma, vma->vm_file NULL checks - these will > always be non-NULL if you reached the mmap hook logic. >=20 > We retain log output for consistency, but change what's output on page > mapping to indicate that sg_discontig_get() does the work now. >=20 > Note that we drop the VMA_IO_BIT flag for the VMA here. It was never > necessary as we invoke alloc_pages() which gives us refcounted folios that > are fine for GUP to access (VMA_IO_BIT would prevent that). >=20 > Reviewed-by: Suren Baghdasaryan > Signed-off-by: Lorenzo Stoakes (ARM) Sashiko has reviewed this patch and found no issues. It looks great! --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261009-b4-mmap-pr= epare-vma-flag-sanify-v5-0-923b70125b1e@kernel.org?part=3D17