From patchwork Tue Sep 21 16:33:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Axel Rasmussen X-Patchwork-Id: 12508313 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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable 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 ACD9AC433F5 for ; Tue, 21 Sep 2021 16:33:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 93E3760F6D for ; Tue, 21 Sep 2021 16:33:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229594AbhIUQe6 (ORCPT ); Tue, 21 Sep 2021 12:34:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37320 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229546AbhIUQe6 (ORCPT ); Tue, 21 Sep 2021 12:34:58 -0400 Received: from mail-qk1-x74a.google.com (mail-qk1-x74a.google.com [IPv6:2607:f8b0:4864:20::74a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A70A5C061575 for ; Tue, 21 Sep 2021 09:33:29 -0700 (PDT) Received: by mail-qk1-x74a.google.com with SMTP id h10-20020a05620a284a00b003d30e8c8cb5so180943824qkp.11 for ; Tue, 21 Sep 2021 09:33:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=NgPoad1ME6wlZVXGi4jGZtPG1kpzd8MCngh0GNGmSTU=; b=OiBXpaE7L7Cg8Vn+IE64i4Bmc0+OP/WPBKzNQewvjrlr6POIZZk+Ky9xhXty8SZ8lP RKxJXIhHc5So/Kp1f68gaaPk7U39WA10s+ztBJQqJfPxLoF0mZBXA7tGzbDhd825rFfR OH+uArjVvTx1MmoJDVDAVESSeAa8gD35aUj6Sr7xwfWGttxUFmpNkbMIg3X/mugBdbu5 aq0ToSOB8bOQFJE0lUjmNAhqmbDtq0DufSUQX6+e99zp5bZVrWrWRLKdKgrU7d1V0SD8 Fme80gZSqKVTyHq2gQoPVM/Twl/7ePPdwGWN9p7x17VmTMfkNdj1lKr16+dl7pSk0FWO eKOw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=NgPoad1ME6wlZVXGi4jGZtPG1kpzd8MCngh0GNGmSTU=; b=KIRLPgtwI6qE2fOckuLPXe1z6dqK2kcDLOQHI+JF7+03vwOCWDtl4ZDPYaTjtqXfPU Lc5Cz2VpwSycTvCagC+swhjkwLl4nHcT+UsRw0KK/r4LexBCBLKB5mKptnO6hXxDGhl+ gad4AXywBoyVOXKasW5f5mT/YWDhIczSeR67yzu3rt/VpPUwBIAaw7/qttlmVeyPpuva Od4xQV5a9QVGFJeBbRAHw/dM9rTFFVWFM3p+NJsOyP0TFZDrdSvDL1p7JOqmp/tlHyek DsQSbP3YW3OJtxXACpySrUx0jXgZGDbhMHSFEgkAOU8IexKSd5kKJ7T2Lvg71n7hW4/h lLEA== X-Gm-Message-State: AOAM530Q8Z2bmlViERIIwbl142sXNQrSTUow78NGJJzWi5lZUWK1EQhq 0X1g4XlNYn8lmZEAEXGuqbGwIEQZeoiddZNJ9r/8 X-Google-Smtp-Source: ABdhPJzFUqv9WN4LgLUzjGZJ0PdywLcz6io6aPqJZC1htFwB2/tNqKY4+zhvKxW6rLMTqAezbaRHM8hF3wMx62GMdI3q X-Received: from ajr0.svl.corp.google.com ([2620:15c:2cd:203:ed57:a230:8c3d:64d8]) (user=axelrasmussen job=sendgmr) by 2002:ad4:4873:: with SMTP id u19mr32664806qvy.11.1632242008820; Tue, 21 Sep 2021 09:33:28 -0700 (PDT) Date: Tue, 21 Sep 2021 09:33:22 -0700 In-Reply-To: <20210921163323.944352-1-axelrasmussen@google.com> Message-Id: <20210921163323.944352-2-axelrasmussen@google.com> Mime-Version: 1.0 References: <20210921163323.944352-1-axelrasmussen@google.com> X-Mailer: git-send-email 2.33.0.464.g1972c5931b-goog Subject: [PATCH 2/3] userfaultfd/selftests: fix calculation of expected ioctls From: Axel Rasmussen To: Andrew Morton , Peter Xu , Shuah Khan Cc: linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, Axel Rasmussen Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Currently, the list of expected ioctls is stored in uffd_test_ops. This design comes with the implicit assumption that the set of expected ioctls is a function of the memory type (anon, shmem, or hugetlb). However, this is not the case. For example: - UFFDIO_WRITEPROTECT is supported for anon in general, *but not on aarch64* (which lacks CONFIG_HAVE_ARCH_USERFAULTFD_WP). - UFFDIO_WRITEPROTECT is supported for anon, but only if one registers the region with UFFD_REGISTER_MODE_WP. - We want to test (and expect) UFFDIO_CONTINUE, but only for *shared* hugetlb, not private. So, instead, remove the set of expected ioctls from this structure. Define a new function which can compute the correct set by examining the memory type, the userfaultfd registration mode(s), whether map_shared is set, and what set of features the kernel reports as supported (from UFFDIO_API). In addition to being more correct, this improves code re-use - less boilerplate in each test trying to perform this assertion. Signed-off-by: Axel Rasmussen --- tools/testing/selftests/vm/userfaultfd.c | 103 ++++++++++++----------- 1 file changed, 56 insertions(+), 47 deletions(-) diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c index 2366caf90435..aad5211f5012 100644 --- a/tools/testing/selftests/vm/userfaultfd.c +++ b/tools/testing/selftests/vm/userfaultfd.c @@ -304,37 +304,24 @@ static void shmem_alias_mapping(__u64 *start, size_t len, unsigned long offset) } struct uffd_test_ops { - unsigned long expected_ioctls; void (*allocate_area)(void **alloc_area); void (*release_pages)(char *rel_area); void (*alias_mapping)(__u64 *start, size_t len, unsigned long offset); }; -#define SHMEM_EXPECTED_IOCTLS ((1 << _UFFDIO_WAKE) | \ - (1 << _UFFDIO_COPY) | \ - (1 << _UFFDIO_ZEROPAGE)) - -#define ANON_EXPECTED_IOCTLS ((1 << _UFFDIO_WAKE) | \ - (1 << _UFFDIO_COPY) | \ - (1 << _UFFDIO_ZEROPAGE) | \ - (1 << _UFFDIO_WRITEPROTECT)) - static struct uffd_test_ops anon_uffd_test_ops = { - .expected_ioctls = ANON_EXPECTED_IOCTLS, .allocate_area = anon_allocate_area, .release_pages = anon_release_pages, .alias_mapping = noop_alias_mapping, }; 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 = shmem_alias_mapping, }; static struct uffd_test_ops hugetlb_uffd_test_ops = { - .expected_ioctls = UFFD_API_RANGE_IOCTLS_BASIC & ~(1 << _UFFDIO_CONTINUE), .allocate_area = hugetlb_allocate_area, .release_pages = hugetlb_release_pages, .alias_mapping = hugetlb_alias_mapping, @@ -368,6 +355,47 @@ static inline bool uffd_wp_supported(void) (uffd_features & UFFD_FEATURE_PAGEFAULT_FLAG_WP); } +static inline uint64_t uffd_minor_feature(void) +{ + if (test_type == TEST_HUGETLB && map_shared) + return UFFD_FEATURE_MINOR_HUGETLBFS; + else if (test_type == TEST_SHMEM) + return UFFD_FEATURE_MINOR_SHMEM; + else + return 0; +} + +static inline bool uffd_minor_supported(void) +{ + return uffd_features & uffd_minor_feature(); +} + +static unsigned long get_expected_ioctls(uint64_t mode) +{ + unsigned long ioctls = UFFD_API_RANGE_IOCTLS; + + if (test_type == TEST_HUGETLB) + ioctls &= ~(1 << _UFFDIO_ZEROPAGE); + + if (!((mode & UFFDIO_REGISTER_MODE_WP) && uffd_wp_supported())) + ioctls &= ~(1 << _UFFDIO_WRITEPROTECT); + + if (!((mode & UFFDIO_REGISTER_MODE_MINOR) && uffd_minor_supported())) + ioctls &= ~(1 << _UFFDIO_CONTINUE); + + return ioctls; +} + +static inline void assert_expected_ioctls_present(uint64_t mode, uint64_t ioctls) +{ + uint64_t expected = get_expected_ioctls(mode); + uint64_t actual = ioctls & expected; + + if (actual != expected) + err("missing ioctl(s); expected: %"PRIx64" actual: %"PRIx64, + expected, actual); +} + static inline void munmap_area(void **area) { if (*area) @@ -1012,11 +1040,9 @@ static int __uffdio_zeropage(int ufd, unsigned long offset, bool retry) { struct uffdio_zeropage uffdio_zeropage; int ret; - unsigned long has_zeropage; + bool has_zeropage = get_expected_ioctls(0) & (1 << _UFFDIO_ZEROPAGE); __s64 res; - has_zeropage = uffd_test_ops->expected_ioctls & (1 << _UFFDIO_ZEROPAGE); - if (offset >= nr_pages * page_size) err("unexpected offset %lu", offset); uffdio_zeropage.range.start = (unsigned long) area_dst + offset; @@ -1056,7 +1082,6 @@ static int uffdio_zeropage(int ufd, unsigned long offset) static int userfaultfd_zeropage_test(void) { struct uffdio_register uffdio_register; - unsigned long expected_ioctls; printf("testing UFFDIO_ZEROPAGE: "); fflush(stdout); @@ -1071,9 +1096,8 @@ static int userfaultfd_zeropage_test(void) if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register)) err("register failure"); - expected_ioctls = uffd_test_ops->expected_ioctls; - if ((uffdio_register.ioctls & expected_ioctls) != expected_ioctls) - err("unexpected missing ioctl for anon memory"); + assert_expected_ioctls_present( + uffdio_register.mode, uffdio_register.ioctls); if (uffdio_zeropage(uffd, 0)) if (my_bcmp(area_dst, zeropage, page_size)) @@ -1086,7 +1110,6 @@ static int userfaultfd_zeropage_test(void) static int userfaultfd_events_test(void) { struct uffdio_register uffdio_register; - unsigned long expected_ioctls; pthread_t uffd_mon; int err; pid_t pid; @@ -1109,9 +1132,8 @@ static int userfaultfd_events_test(void) if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register)) err("register failure"); - expected_ioctls = uffd_test_ops->expected_ioctls; - if ((uffdio_register.ioctls & expected_ioctls) != expected_ioctls) - err("unexpected missing ioctl for anon memory"); + assert_expected_ioctls_present( + uffdio_register.mode, uffdio_register.ioctls); if (pthread_create(&uffd_mon, &attr, uffd_poll_thread, &stats)) err("uffd_poll_thread create"); @@ -1139,7 +1161,6 @@ static int userfaultfd_events_test(void) static int userfaultfd_sig_test(void) { struct uffdio_register uffdio_register; - unsigned long expected_ioctls; unsigned long userfaults; pthread_t uffd_mon; int err; @@ -1163,9 +1184,8 @@ static int userfaultfd_sig_test(void) if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register)) err("register failure"); - expected_ioctls = uffd_test_ops->expected_ioctls; - if ((uffdio_register.ioctls & expected_ioctls) != expected_ioctls) - err("unexpected missing ioctl for anon memory"); + assert_expected_ioctls_present( + uffdio_register.mode, uffdio_register.ioctls); if (faulting_process(1)) err("faulting process failed"); @@ -1200,30 +1220,25 @@ static int userfaultfd_sig_test(void) static int userfaultfd_minor_test(void) { struct uffdio_register uffdio_register; - unsigned long expected_ioctls; unsigned long p; pthread_t uffd_mon; uint8_t expected_byte; void *expected_page; char c; struct uffd_stats stats = { 0 }; - uint64_t features; + uint64_t features = uffd_minor_feature(); printf("testing minor faults: "); fflush(stdout); - if (test_type == TEST_HUGETLB && map_shared) - features = UFFD_FEATURE_MINOR_HUGETLBFS; - else if (test_type == TEST_SHMEM) - features = UFFD_FEATURE_MINOR_SHMEM; - else { + if (!features) { printf("skipping test due to unsupported memory type\n"); + fflush(stdout); return 0; } uffd_test_ctx_init(features); - /* If kernel reports required features aren't supported, skip test. */ - if ((uffd_features & features) != features) { + if (!uffd_minor_supported()) { printf("skipping test due to lack of feature support\n"); fflush(stdout); return 0; @@ -1235,10 +1250,8 @@ static int userfaultfd_minor_test(void) if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register)) err("register failure"); - expected_ioctls = uffd_test_ops->expected_ioctls; - expected_ioctls |= 1 << _UFFDIO_CONTINUE; - if ((uffdio_register.ioctls & expected_ioctls) != expected_ioctls) - err("unexpected missing ioctl(s)"); + assert_expected_ioctls_present( + uffdio_register.mode, uffdio_register.ioctls); /* * After registering with UFFD, populate the non-UFFD-registered side of @@ -1436,8 +1449,6 @@ static int userfaultfd_stress(void) pthread_attr_setstacksize(&attr, 16*1024*1024); while (bounces--) { - unsigned long expected_ioctls; - printf("bounces: %d, mode:", bounces); if (bounces & BOUNCE_RANDOM) printf(" rnd"); @@ -1465,10 +1476,8 @@ static int userfaultfd_stress(void) uffdio_register.mode |= UFFDIO_REGISTER_MODE_WP; if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register)) err("register failure"); - expected_ioctls = uffd_test_ops->expected_ioctls; - if ((uffdio_register.ioctls & expected_ioctls) != - expected_ioctls) - err("unexpected missing ioctl for anon memory"); + assert_expected_ioctls_present( + uffdio_register.mode, uffdio_register.ioctls); if (area_dst_alias) { uffdio_register.range.start = (unsigned long)