From nobody Mon Feb 9 23:15:02 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AD87AC77B70 for ; Mon, 10 Apr 2023 13:39:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229849AbjDJNjv (ORCPT ); Mon, 10 Apr 2023 09:39:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59892 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229683AbjDJNjq (ORCPT ); Mon, 10 Apr 2023 09:39:46 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 469C0558B for ; Mon, 10 Apr 2023 06:39:45 -0700 (PDT) Received: from kwepemm600020.china.huawei.com (unknown [172.30.72.53]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4Pw9373GfFzSrKP; Mon, 10 Apr 2023 21:35:47 +0800 (CST) Received: from localhost.localdomain (10.175.112.125) by kwepemm600020.china.huawei.com (7.193.23.147) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.23; Mon, 10 Apr 2023 21:39:40 +0800 From: Peng Zhang To: , , , , , , CC: , , , ZhangPeng Subject: [PATCH v6 1/6] userfaultfd: convert mfill_atomic_pte_copy() to use a folio Date: Mon, 10 Apr 2023 21:39:27 +0800 Message-ID: <20230410133932.32288-2-zhangpeng362@huawei.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230410133932.32288-1-zhangpeng362@huawei.com> References: <20230410133932.32288-1-zhangpeng362@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.175.112.125] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To kwepemm600020.china.huawei.com (7.193.23.147) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: ZhangPeng Call vma_alloc_folio() directly instead of alloc_page_vma() and convert page_kaddr to kaddr in mfill_atomic_pte_copy(). Removes several calls to compound_head(). Signed-off-by: ZhangPeng Reviewed-by: Sidhartha Kumar Reviewed-by: Mike Kravetz --- mm/userfaultfd.c | 32 ++++++++++++++++---------------- 1 file changed, 16 insertions(+), 16 deletions(-) diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 7f1b5f8b712c..313bc683c2b6 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -135,17 +135,18 @@ static int mfill_atomic_pte_copy(pmd_t *dst_pmd, uffd_flags_t flags, struct page **pagep) { - void *page_kaddr; + void *kaddr; int ret; - struct page *page; + struct folio *folio; =20 if (!*pagep) { ret =3D -ENOMEM; - page =3D alloc_page_vma(GFP_HIGHUSER_MOVABLE, dst_vma, dst_addr); - if (!page) + folio =3D vma_alloc_folio(GFP_HIGHUSER_MOVABLE, 0, dst_vma, + dst_addr, false); + if (!folio) goto out; =20 - page_kaddr =3D kmap_local_page(page); + kaddr =3D kmap_local_folio(folio, 0); /* * The read mmap_lock is held here. Despite the * mmap_lock being read recursive a deadlock is still @@ -162,45 +163,44 @@ static int mfill_atomic_pte_copy(pmd_t *dst_pmd, * and retry the copy outside the mmap_lock. */ pagefault_disable(); - ret =3D copy_from_user(page_kaddr, - (const void __user *) src_addr, + ret =3D copy_from_user(kaddr, (const void __user *) src_addr, PAGE_SIZE); pagefault_enable(); - kunmap_local(page_kaddr); + kunmap_local(kaddr); =20 /* fallback to copy_from_user outside mmap_lock */ if (unlikely(ret)) { ret =3D -ENOENT; - *pagep =3D page; + *pagep =3D &folio->page; /* don't free the page */ goto out; } =20 - flush_dcache_page(page); + flush_dcache_folio(folio); } else { - page =3D *pagep; + folio =3D page_folio(*pagep); *pagep =3D NULL; } =20 /* - * The memory barrier inside __SetPageUptodate makes sure that + * The memory barrier inside __folio_mark_uptodate makes sure that * preceding stores to the page contents become visible before * the set_pte_at() write. */ - __SetPageUptodate(page); + __folio_mark_uptodate(folio); =20 ret =3D -ENOMEM; - if (mem_cgroup_charge(page_folio(page), dst_vma->vm_mm, GFP_KERNEL)) + if (mem_cgroup_charge(folio, dst_vma->vm_mm, GFP_KERNEL)) goto out_release; =20 ret =3D mfill_atomic_install_pte(dst_pmd, dst_vma, dst_addr, - page, true, flags); + &folio->page, true, flags); if (ret) goto out_release; out: return ret; out_release: - put_page(page); + folio_put(folio); goto out; } =20 --=20 2.25.1