From patchwork Tue Mar 2 00:01:31 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Axel Rasmussen X-Patchwork-Id: 12110825 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=-16.6 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 A8F0AC433E9 for ; Tue, 2 Mar 2021 00:01:49 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 5AC456024A for ; Tue, 2 Mar 2021 00:01:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5AC456024A Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 00B9B8D00BB; Mon, 1 Mar 2021 19:01:49 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E3D4D8D0063; Mon, 1 Mar 2021 19:01:48 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C8CEC8D00BB; Mon, 1 Mar 2021 19:01:48 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0158.hostedemail.com [216.40.44.158]) by kanga.kvack.org (Postfix) with ESMTP id A78CB8D0063 for ; Mon, 1 Mar 2021 19:01:48 -0500 (EST) Received: from smtpin07.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 618A55DEE for ; Tue, 2 Mar 2021 00:01:48 +0000 (UTC) X-FDA: 77872980696.07.269D427 Received: from mail-yb1-f202.google.com (mail-yb1-f202.google.com [209.85.219.202]) by imf13.hostedemail.com (Postfix) with ESMTP id 7F1DFE0A3A05 for ; Tue, 2 Mar 2021 00:01:43 +0000 (UTC) Received: by mail-yb1-f202.google.com with SMTP id v6so20660317ybk.9 for ; Mon, 01 Mar 2021 16:01:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=ga+3+HU/1O4PWNGcBy73JW1dDRIoBKvdkJlksQhtYJk=; b=uZhxFptRedsgKaKz9OLDGSC/FW+v3PDlF/1VW4uc6WxsSJPdzbOnoaHonj62Tpf2Rp 9djnZP2FZSRaquC1Z35N7BlgMdnQY+YTOj3lSji670HF0XsnEilodOWgZ3y0Yvz7azqc eIHFdcTK0ubG29dgJPKjYXW95boO5NDDIZNy3ZMda6PAMjQisn6LfG1k0JI/gvy0ieab aMZ7kckpt2US41i92QXtYfdDShOJJt9G65y9cAbQsCU72ljS2chnl690UVfwkIad3wzM G3ENscyoG3eNGlEckLNaECjJMKHGCwPlGDY56IqtzEaKnYAi//P0StXf2J3gu3PcFcnW /S7w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=ga+3+HU/1O4PWNGcBy73JW1dDRIoBKvdkJlksQhtYJk=; b=StVLxEtTtHNSOvX/8nXACQdDK1scT4GNw8eAwaMY/5A3w4dSV1ES7sKVwwro/3Ji9p ZAgztSmcPJ/E5aJRF2U4nW5IOtH/f9n21OrXwlwgrRemH41jiAsBo2JK5B3gOl0VM6ZQ LL4jJe7iv55oJn0piU6PzrpYybhBtcswPtWjx9c80ij7z9FJRI6khh3DgVwa7/x9sIZa z5KyT6XBAqKmboRyO3b2PInSub2xSnqAMNozKZKn3nszBaDSuFzFNbUqHSaMD78GsrqX Ks8IhOe46jM35QMBhs3SfKCMrHqrehr4yELjyuNpLwarZMeFWA1PmcLqV0+p2pVFU5W9 hxEw== X-Gm-Message-State: AOAM5317PzsFZUMGoaVoorfv3aRCUT74X84YhFiOO6Vcfni617jCwbpa bS3aR1lDcd5+xT+22ecGGLoOB332sjUmuAnj3Nsz X-Google-Smtp-Source: ABdhPJy2fJwEaq8pxSZCQdXMcW7Yms/ycMK7J/aYvRmsWqsh5YosxRt/wHxAvNdhN8dxc4qvYBp3ldGNeoeAhoFzj5wb X-Received: from ajr0.svl.corp.google.com ([2620:15c:2cd:203:1998:8165:ca50:ab8d]) (user=axelrasmussen job=sendgmr) by 2002:a25:aae2:: with SMTP id t89mr29309195ybi.63.1614643303192; Mon, 01 Mar 2021 16:01:43 -0800 (PST) Date: Mon, 1 Mar 2021 16:01:31 -0800 In-Reply-To: <20210302000133.272579-1-axelrasmussen@google.com> Message-Id: <20210302000133.272579-4-axelrasmussen@google.com> Mime-Version: 1.0 References: <20210302000133.272579-1-axelrasmussen@google.com> X-Mailer: git-send-email 2.30.1.766.gb4fecdf3b7-goog Subject: [PATCH v2 3/5] userfaultfd/selftests: create alias mappings in the shmem test From: Axel Rasmussen To: Alexander Viro , Andrea Arcangeli , Andrew Morton , Hugh Dickins , Jerome Glisse , Joe Perches , Lokesh Gidra , Mike Rapoport , Peter Xu , Shaohua Li , Shuah Khan , Wang Qing Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, Axel Rasmussen , Brian Geffon , Cannon Matthews , "Dr . David Alan Gilbert" , David Rientjes , Michel Lespinasse , Mina Almasry , Oliver Upton X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 7F1DFE0A3A05 X-Stat-Signature: pgfjqhpsdxuspf4odpp383de1ugpgdq9 Received-SPF: none (flex--axelrasmussen.bounces.google.com>: No applicable sender policy available) receiver=imf13; identity=mailfrom; envelope-from="<3Z4A9YA0KCGYEbIPVEWQYWWIRKSSKPI.GSQPMRYb-QQOZEGO.SVK@flex--axelrasmussen.bounces.google.com>"; helo=mail-yb1-f202.google.com; client-ip=209.85.219.202 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1614643303-318541 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: 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. Signed-off-by: Axel Rasmussen --- tools/testing/selftests/vm/userfaultfd.c | 29 +++++++++++++++++++++--- 1 file changed, 26 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c index 859398efb4fe..4a18590fe0f8 100644 --- a/tools/testing/selftests/vm/userfaultfd.c +++ b/tools/testing/selftests/vm/userfaultfd.c @@ -298,8 +298,9 @@ static int shmem_release_pages(char *rel_area) 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); @@ -308,12 +309,34 @@ static void shmem_allocate_area(void **alloc_area) goto fail; } + area_alias = mmap(NULL, nr_pages * page_size, PROT_READ | PROT_WRITE, + MAP_SHARED, shm_fd, offset); + if (area_alias == MAP_FAILED) { + perror("mmap of memfd alias failed"); + goto fail_munmap; + } + + if (is_src) + area_src_alias = area_alias; + else + area_dst_alias = area_alias; + return; +fail_munmap: + if (munmap(*alloc_area, nr_pages * page_size) < 0) { + perror("munmap of memfd failed\n"); + exit(1); + } fail: *alloc_area = NULL; } +static void shmem_alias_mapping(__u64 *start, size_t len, unsigned long offset) +{ + *start = (unsigned long)area_dst_alias + offset; +} + struct uffd_test_ops { unsigned long expected_ioctls; void (*allocate_area)(void **alloc_area); @@ -341,7 +364,7 @@ static struct uffd_test_ops shmem_uffd_test_ops = { .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 = {