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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id F047FCFA466 for ; Mon, 24 Nov 2025 11:03:28 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 45E0F6B0098; Mon, 24 Nov 2025 06:03:28 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 435736B0099; Mon, 24 Nov 2025 06:03:28 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 34B0B6B009B; Mon, 24 Nov 2025 06:03:28 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 1FCE66B0098 for ; Mon, 24 Nov 2025 06:03:28 -0500 (EST) Received: from smtpin24.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id A7CC64ECE7 for ; Mon, 24 Nov 2025 11:03:27 +0000 (UTC) X-FDA: 84145214454.24.FC6D3AE Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf19.hostedemail.com (Postfix) with ESMTP id 082341A0004 for ; Mon, 24 Nov 2025 11:03:25 +0000 (UTC) Authentication-Results: imf19.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=tAXJgd8K; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf19.hostedemail.com: domain of david@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=david@kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1763982206; a=rsa-sha256; cv=none; b=GBhqOz4UvG25o57QFVnyfQ1Dq9UH4jqh6ucxBSbUkTVTXhXvni9MiROGR7LZhJohgmnwVC dTWXg+lieki01FJv5bIGjWvRCQS8mj/UZnyro4l6xHTeKIn0k1l9neSbHqy6rCRLXOjwOy TWhOKjr8EctVEO8Kriwx644E7ThBrUU= ARC-Authentication-Results: i=1; imf19.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=tAXJgd8K; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf19.hostedemail.com: domain of david@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=david@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1763982206; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=Sy6WqMY6M1O1R0n5g1DBh8RjPYVNARXygJZgYeGGgjo=; b=wGKMPL+yxppOmPK2kurugAM8UoDtGWxmVLelm5PQ20L4fZbkRR/LBTyrYPG2+azEqolMWz Rv/X6UhhHxAwcGzATgvFVHLe3mYedkRcCBRXQizEDJES0hhVWtE1PzKYPGRS8CJBDwFbvo IwfTv99r20HnY9nSlBDvEof+N5cIEbM= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 357DE60190; Mon, 24 Nov 2025 11:03:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D0E8FC4CEFB; Mon, 24 Nov 2025 11:03:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1763982204; bh=dPX6RM/71Vh3Rg6mMUUHNMjki5uHeW9Di7AFUe06SIM=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=tAXJgd8KRu8Q5V9aLwauZ1k+fElq8tVU+jgRk9V8z9tI8Wt82uOnUMl4A41BAxhlH a97WXS50IpqSn9hKKdunuS4HBW2ES2f0Vv6k68wx8XxHSXmvVPAbatbuM8ocpG2k3s W78fXij3OS3qK5KaDT+OO9o+l8Csdaj/Xz161iBtcKql4r5F2AgBR/M2a25HYp1yHD b81IFqXfFkgCxXe0QBvBzGoAjRknxrnmYYbwqgP6tqBPcxW/GAuT4vGKtCGbRpmb86 8p6A0ytk0HtSUfUyuLrEC3z7MWaPMnyKG8LvVPtKjJw3gd3LZCWvJj/PwioCnqL9fY mJK76Wr1oG7pQ== Message-ID: Date: Mon, 24 Nov 2025 12:03:17 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 2/5] userfaultfd, shmem: use a VMA callback to handle UFFDIO_CONTINUE To: Mike Rapoport , linux-mm@kvack.org Cc: Andrea Arcangeli , Andrew Morton , Axel Rasmussen , Baolin Wang , Hugh Dickins , James Houghton , "Liam R. Howlett" , Lorenzo Stoakes , Michal Hocko , Nikita Kalyazin , Paolo Bonzini , Peter Xu , Sean Christopherson , Shuah Khan , Suren Baghdasaryan , Vlastimil Babka , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org References: <20251123102707.559422-1-rppt@kernel.org> <20251123102707.559422-3-rppt@kernel.org> From: "David Hildenbrand (Red Hat)" Content-Language: en-US In-Reply-To: <20251123102707.559422-3-rppt@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 082341A0004 X-Stat-Signature: 4xxtwzsau1iwb4sdjfkae6xfk4kfye9z X-HE-Tag: 1763982205-92784 X-HE-Meta: U2FsdGVkX1/Dy2FGr/u77BUbwNB9OQZAJnqVQb1vn53u+S4kF7LlbCo2wwYdWt6aTQ1KtEukvBUKXJoriOVUChUGHrLIpW2te5QvpECLiG91HKjTyz1ZNmXQAoKXTe0I+Cxh6S7bKnA4L9f2he3O4zjLgDmETj+Sxip2MPEA/TX4QAEz9ie7yLVEDQiXoHO8k7WCP66Gq/rNMVRe0diRKoHhvLfmgBUfWbe2UOSymCZNR6vWQosLlvnvS4qIKR37zMRZsRGLjcI/4n29u/SH9RF8C8gRkSWmRY8SStK/YZrVuE0Hbc8UY9jyyLpY9bCq9ZNEluf83bamuoBjZ1EErkBsc+xMgTIArMuWT6OODMWwsJKicfEwB4IYFSMZuc4kIbFsdACVxZ/PJfG4smh0+/uKBOcPYafzObBwfC7SEXgfin0SGGEu/KTmuB/RKxR8bBqsVzIMQ6PCEs0Z7OQA8ggWdwfcdc+APL9DEY1GHKxl4JleFXzn5XfMdufxPRW4pE2ySUzMlppQivx4xIx375FLBez3eDQkek0m6/YcquMRUFohDbfY6zoGmWbAbPOyspiqcScAABStjowhq1BzZf5wRwCo9aYRWKOiTFxWQtc2zpv9XBywZmaSQ0/BYkQ8sElQLa+S0dLaXyBrKT8njjGFtE9/YdHVl6JCXX2tFqvjbN+X1Y7urupi3U38ceK14Fd5QmJ9a2I5HQ2t+wbXuMtRLyeld2Oan66oZmH85vo9WUP87mI/AyUNoDMjtAdtMqBxkOtCcypu0NGRFO64Svawv1k9iiCWUpX4apaWP6Lc0+ZU79ayJ9lU75U6u/mLDomBWQc2KBggcM8Pa+GIPAAtjmChnksMQh1UL//P6R/xKVwpo3pcvQ3mwTgwzQqaEAEzM3LtqrJCyHqOFnWRLym2ZZoG8RAkDIRWiQb18W1GiUaK56xMeajT1iBLCcrE7fu/TREQ5qv+OWiorzP AdcAQTxV BUSbYSwsBvyN6vOieOj1d9MiXxP7M73hfJcxyKuS8brKEFCEgkViaBgtZon5qYvgaihUQG+oST4prwbeOLtObcND76r/5bO1svXZUQ9QyROr1iEHDUwPI239+uNfTstL5FXUa6JjJsagtnTifVsf1VrWODEvNjh51LF/avkrZrsqKFdR9ZHCCgdxvh4FVUW1UgfZMpA+YXwmi6qXzYRsNujxDbWA1tTiZ6QetJcQw3oMwrbbaJEk/Hua+US10iO2DyIwIyUg3IsSuNalNzYw0WOe85GZ7l59PZQFPiSEr+J+loV75pm9ft5wxFfySUOfcWZXOzNT+f5Ne5f0= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 11/23/25 11:27, Mike Rapoport wrote: > From: "Mike Rapoport (Microsoft)" > > When userspace resolves a page fault in a shmem VMA with UFFDIO_CONTINUE > it needs to get a folio that already exists in the pagecache backing > that VMA. > > Instead of using shmem_get_folio() for that, add a get_pagecache_folio() get_shared_folio() Given that the helper now no longer receives a VMA, I assume we can just really call it get_folio() and the "shared" part would be implicit. (from the inode) > method to 'struct vm_operations_struct' that will return a folio if it > exists in the VMA's pagecache at given pgoff. > > Implement get_pagecache_folio() method for shmem and slightly refactor > userfaultfd's mfill_atomic() and mfill_atomic_pte_continue() to support > this new API. > > Signed-off-by: Mike Rapoport (Microsoft) > --- Nothing else jumped at me :) -- Cheers David