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 X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_RED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0B715C11F68 for ; Thu, 1 Jul 2021 01:49:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EE07161466 for ; Thu, 1 Jul 2021 01:49:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238412AbhGABwK (ORCPT ); Wed, 30 Jun 2021 21:52:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:41552 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238384AbhGABwJ (ORCPT ); Wed, 30 Jun 2021 21:52:09 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 920F56105A; Thu, 1 Jul 2021 01:49:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1625104179; bh=8KNx8WWwsmy+fp9z4NZNRRslQL5pls+oaMECB9+Zhck=; h=Date:From:To:Subject:In-Reply-To:From; b=JxmEYO5JkJ+cIjVXjKqqA3wk011M9JxTemfdg7Gsg2YLoANskoZYzc748HEDLBpIm MPAp0649Ea/hbcYplM8UoHGMScQhNkFK4tXugpXSMRRYphxAZRw1dRWA0pY8/hvTVu Bdf/5pxjn7q+veK3uJexUt7VlqEWWJ0IymkYYztY= Date: Wed, 30 Jun 2021 18:49:38 -0700 From: Andrew Morton To: aarcange@redhat.com, akpm@linux-foundation.org, almasrymina@google.com, axelrasmussen@google.com, bgeffon@google.com, dgilbert@redhat.com, hughd@google.com, jglisse@redhat.com, joe@perches.com, kirill@shutemov.name, linux-mm@kvack.org, lokeshgidra@google.com, mike.kravetz@oracle.com, mm-commits@vger.kernel.org, oupton@google.com, peterx@redhat.com, rppt@linux.vnet.ibm.com, sfr@canb.auug.org.au, shli@fb.com, shuah@kernel.org, torvalds@linux-foundation.org, viro@zeniv.linux.org.uk, wangqing@vivo.com Subject: [patch 046/192] userfaultfd/selftests: create alias mappings in the shmem test Message-ID: <20210701014938.PK7FRdk21%akpm@linux-foundation.org> In-Reply-To: <20210630184624.9ca1937310b0dd5ce66b30e7@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Axel Rasmussen Subject: userfaultfd/selftests: create alias mappings in the shmem test Previously, we just allocated two shm areas: area_src and area_dst. With this commit, change this so we also allocate area_src_alias, and area_dst_alias. area_*_alias and area_* (respectively) point to the same underlying physical pages, but are different VMAs. In a future commit in this series, we'll leverage this setup to exercise minor fault handling support for shmem, just like we do in the hugetlb_shared test. Link: https://lkml.kernel.org/r/20210503180737.2487560-9-axelrasmussen@google.com Signed-off-by: Axel Rasmussen Reviewed-by: Peter Xu Cc: Alexander Viro Cc: Andrea Arcangeli Cc: Brian Geffon Cc: "Dr . David Alan Gilbert" Cc: Hugh Dickins Cc: Jerome Glisse Cc: Joe Perches Cc: Kirill A. Shutemov Cc: Lokesh Gidra Cc: Mike Kravetz Cc: Mike Rapoport Cc: Mina Almasry Cc: Oliver Upton Cc: Shaohua Li Cc: Shuah Khan Cc: Stephen Rothwell Cc: Wang Qing Signed-off-by: Andrew Morton --- tools/testing/selftests/vm/userfaultfd.c | 22 ++++++++++++++++++--- 1 file changed, 19 insertions(+), 3 deletions(-) --- a/tools/testing/selftests/vm/userfaultfd.c~userfaultfd-selftests-create-alias-mappings-in-the-shmem-test +++ a/tools/testing/selftests/vm/userfaultfd.c @@ -278,13 +278,29 @@ static void shmem_release_pages(char *re static void shmem_allocate_area(void **alloc_area) { - unsigned long offset = - alloc_area == (void **)&area_src ? 0 : nr_pages * page_size; + void *area_alias = NULL; + bool is_src = alloc_area == (void **)&area_src; + unsigned long offset = is_src ? 0 : nr_pages * page_size; *alloc_area = mmap(NULL, nr_pages * page_size, PROT_READ | PROT_WRITE, MAP_SHARED, shm_fd, offset); if (*alloc_area == MAP_FAILED) err("mmap of memfd failed"); + + area_alias = mmap(NULL, nr_pages * page_size, PROT_READ | PROT_WRITE, + MAP_SHARED, shm_fd, offset); + if (area_alias == MAP_FAILED) + err("mmap of memfd alias failed"); + + if (is_src) + area_src_alias = area_alias; + else + area_dst_alias = area_alias; +} + +static void shmem_alias_mapping(__u64 *start, size_t len, unsigned long offset) +{ + *start = (unsigned long)area_dst_alias + offset; } struct uffd_test_ops { @@ -314,7 +330,7 @@ static struct uffd_test_ops shmem_uffd_t .expected_ioctls = SHMEM_EXPECTED_IOCTLS, .allocate_area = shmem_allocate_area, .release_pages = shmem_release_pages, - .alias_mapping = noop_alias_mapping, + .alias_mapping = shmem_alias_mapping, }; static struct uffd_test_ops hugetlb_uffd_test_ops = { _