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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 82B34E748ED for ; Mon, 2 Oct 2023 16:00:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238319AbjJBQAW (ORCPT ); Mon, 2 Oct 2023 12:00:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39212 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238331AbjJBQAT (ORCPT ); Mon, 2 Oct 2023 12:00:19 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5D07A93 for ; Mon, 2 Oct 2023 09:00:16 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DF878C433C8; Mon, 2 Oct 2023 16:00:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1696262416; bh=LpbZvZAwf0iA3tGj59pM2hJjPZamRCmv7ealvK0URZc=; h=Date:To:From:Subject:From; b=PzWQosHgQw9ZijZYHn91I5HWvQjNcDrxKqwuvZXTgt0y8RY0T1Ke8sbHlLIl1qQBl uk9n4R+p5ZBmguIwTxMHyiJGngt7GCbkvuApdlRqtmL08De5DoFc707kPOF41ULJUS wSyOWb8ZHHVH2gR2pe1qc/3uz+U2FVupDyHjNRqU= Date: Mon, 02 Oct 2023 09:00:15 -0700 To: mm-commits@vger.kernel.org, zhangpeng362@huawei.com, willy@infradead.org, viro@zeniv.linux.org.uk, shuah@kernel.org, rppt@kernel.org, peterx@redhat.com, ngeoffray@google.com, mhocko@suse.com, lokeshgidra@google.com, Liam.Howlett@oracle.com, kaleshsingh@google.com, jannh@google.com, hughd@google.com, david@redhat.com, brauner@kernel.org, bgeffon@google.com, axelrasmussen@google.com, aarcange@redhat.com, surenb@google.com, akpm@linux-foundation.org From: Andrew Morton Subject: [to-be-updated] selftests-mm-add-uffdio_remap-ioctl-test.patch removed from -mm tree Message-Id: <20231002160015.DF878C433C8@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The quilt patch titled Subject: selftests/mm: add UFFDIO_REMAP ioctl test has been removed from the -mm tree. Its filename was selftests-mm-add-uffdio_remap-ioctl-test.patch This patch was dropped because an updated version will be merged ------------------------------------------------------ From: Suren Baghdasaryan Subject: selftests/mm: add UFFDIO_REMAP ioctl test Date: Fri, 22 Sep 2023 18:31:46 -0700 Add a test for new UFFDIO_REMAP ioctl which uses uffd to remaps source into destination buffer while checking the contents of both after remapping. After the operation the content of the destination buffer should match the original source buffer's content while the source buffer should be zeroed. Link: https://lkml.kernel.org/r/20230923013148.1390521-4-surenb@google.com Signed-off-by: Suren Baghdasaryan Cc: Al Viro Cc: Andrea Arcangeli Cc: Axel Rasmussen Cc: Brian Geffon Cc: Christian Brauner Cc: David Hildenbrand Cc: Hugh Dickins Cc: Jann Horn Cc: Kalesh Singh Cc: "Liam R. Howlett" Cc: Lokesh Gidra Cc: Matthew Wilcox Cc: Michal Hocko Cc: Mike Rapoport (IBM) Cc: Nicolas Geoffray Cc: Peter Xu Cc: Shuah Khan Cc: ZhangPeng Signed-off-by: Andrew Morton --- tools/testing/selftests/mm/uffd-common.c | 41 ++++++++++- tools/testing/selftests/mm/uffd-common.h | 1 tools/testing/selftests/mm/uffd-unit-tests.c | 62 +++++++++++++++++ 3 files changed, 102 insertions(+), 2 deletions(-) --- a/tools/testing/selftests/mm/uffd-common.c~selftests-mm-add-uffdio_remap-ioctl-test +++ a/tools/testing/selftests/mm/uffd-common.c @@ -52,6 +52,13 @@ static int anon_allocate_area(void **all *alloc_area = NULL; return -errno; } + + /* Prevent source pages from collapsing into THPs */ + if (madvise(*alloc_area, nr_pages * page_size, MADV_NOHUGEPAGE)) { + *alloc_area = NULL; + return -errno; + } + return 0; } @@ -484,8 +491,14 @@ void uffd_handle_page_fault(struct uffd_ offset = (char *)(unsigned long)msg->arg.pagefault.address - area_dst; offset &= ~(page_size-1); - if (copy_page(uffd, offset, args->apply_wp)) - args->missing_faults++; + /* UFFD_REMAP is supported for anon non-shared mappings. */ + if (uffd_test_ops == &anon_uffd_test_ops && !map_shared) { + if (remap_page(uffd, offset)) + args->missing_faults++; + } else { + if (copy_page(uffd, offset, args->apply_wp)) + args->missing_faults++; + } } } @@ -620,6 +633,30 @@ int copy_page(int ufd, unsigned long off return __copy_page(ufd, offset, false, wp); } +int remap_page(int ufd, unsigned long offset) +{ + struct uffdio_remap uffdio_remap; + + if (offset >= nr_pages * page_size) + err("unexpected offset %lu\n", offset); + uffdio_remap.dst = (unsigned long) area_dst + offset; + uffdio_remap.src = (unsigned long) area_src + offset; + uffdio_remap.len = page_size; + uffdio_remap.mode = UFFDIO_REMAP_MODE_ALLOW_SRC_HOLES; + uffdio_remap.remap = 0; + if (ioctl(ufd, UFFDIO_REMAP, &uffdio_remap)) { + /* real retval in uffdio_remap.remap */ + if (uffdio_remap.remap != -EEXIST) + err("UFFDIO_REMAP error: %"PRId64, + (int64_t)uffdio_remap.remap); + wake_range(ufd, uffdio_remap.dst, page_size); + } else if (uffdio_remap.remap != page_size) { + err("UFFDIO_REMAP error: %"PRId64, (int64_t)uffdio_remap.remap); + } else + return 1; + return 0; +} + int uffd_open_dev(unsigned int flags) { int fd, uffd; --- a/tools/testing/selftests/mm/uffd-common.h~selftests-mm-add-uffdio_remap-ioctl-test +++ a/tools/testing/selftests/mm/uffd-common.h @@ -111,6 +111,7 @@ void wp_range(int ufd, __u64 start, __u6 void uffd_handle_page_fault(struct uffd_msg *msg, struct uffd_args *args); int __copy_page(int ufd, unsigned long offset, bool retry, bool wp); int copy_page(int ufd, unsigned long offset, bool wp); +int remap_page(int ufd, unsigned long offset); void *uffd_poll_thread(void *arg); int uffd_open_dev(unsigned int flags); --- a/tools/testing/selftests/mm/uffd-unit-tests.c~selftests-mm-add-uffdio_remap-ioctl-test +++ a/tools/testing/selftests/mm/uffd-unit-tests.c @@ -824,6 +824,10 @@ static void uffd_events_test_common(bool char c; struct uffd_args args = { 0 }; + /* Prevent source pages from being mapped more than once */ + if (madvise(area_src, nr_pages * page_size, MADV_DONTFORK)) + err("madvise(MADV_DONTFORK) failed"); + fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK); if (uffd_register(uffd, area_dst, nr_pages * page_size, true, wp, false)) @@ -1062,6 +1066,58 @@ static void uffd_poison_test(uffd_test_a uffd_test_pass(); } +static void uffd_remap_test(uffd_test_args_t *targs) +{ + unsigned long nr; + pthread_t uffd_mon; + char c; + unsigned long long count; + struct uffd_args args = { 0 }; + + if (uffd_register(uffd, area_dst, nr_pages * page_size, + true, false, false)) + err("register failure"); + + if (pthread_create(&uffd_mon, NULL, uffd_poll_thread, &args)) + err("uffd_poll_thread create"); + + /* + * Read each of the pages back using the UFFD-registered mapping. We + * expect that the first time we touch a page, it will result in a missing + * fault. uffd_poll_thread will resolve the fault by remapping source + * page to destination. + */ + for (nr = 0; nr < nr_pages; nr++) { + /* Check area_src content */ + count = *area_count(area_src, nr); + if (count != count_verify[nr]) + err("nr %lu source memory invalid %llu %llu\n", + nr, count, count_verify[nr]); + + /* Faulting into area_dst should remap the page */ + count = *area_count(area_dst, nr); + if (count != count_verify[nr]) + err("nr %lu memory corruption %llu %llu\n", + nr, count, count_verify[nr]); + + /* Re-check area_src content which should be empty */ + count = *area_count(area_src, nr); + if (count != 0) + err("nr %lu remap failed %llu %llu\n", + nr, count, count_verify[nr]); + } + + if (write(pipefd[1], &c, sizeof(c)) != sizeof(c)) + err("pipe write"); + if (pthread_join(uffd_mon, NULL)) + err("join() failed"); + + if (args.missing_faults != nr_pages || args.minor_faults != 0) + uffd_test_fail("stats check error"); + else + uffd_test_pass(); +} + /* * Test the returned uffdio_register.ioctls with different register modes. * Note that _UFFDIO_ZEROPAGE is tested separately in the zeropage test. @@ -1140,6 +1196,12 @@ uffd_test_case_t uffd_tests[] = { .uffd_feature_required = 0, }, { + .name = "remap", + .uffd_fn = uffd_remap_test, + .mem_targets = MEM_ANON, + .uffd_feature_required = 0, + }, + { .name = "wp-fork", .uffd_fn = uffd_wp_fork_test, .mem_targets = MEM_ALL, _ Patches currently in -mm which might be from surenb@google.com are