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=-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 BFB87C433E3 for ; Tue, 23 Mar 2021 18:26:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8EFD5619C0 for ; Tue, 23 Mar 2021 18:26:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231764AbhCWS0G (ORCPT ); Tue, 23 Mar 2021 14:26:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44028 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231613AbhCWSZg (ORCPT ); Tue, 23 Mar 2021 14:25:36 -0400 Received: from mail-pg1-x549.google.com (mail-pg1-x549.google.com [IPv6:2607:f8b0:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8B25FC061574 for ; Tue, 23 Mar 2021 11:25:36 -0700 (PDT) Received: by mail-pg1-x549.google.com with SMTP id f20so2495722pgj.6 for ; Tue, 23 Mar 2021 11:25:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=Jnif/0NMg0aeEcah82nrTBoEGi2KuieYH+LfZPYXFBE=; b=PldZbFVYUScrEaM4fON0VI8wT/uoJ0m9q4USAq66I9zTqtbvN0b2BCRhGvFYBN9Klb qTKc+IDs2lxZJX91+OO/C2Arg0LESyb+wG9JTuavSWrd3XIF8gtw8aGaRuWY2G9ThSgx MfOMqSCyNIcmjTIXhWOG/TomexRy7h9Lk62RkrFndBF7v3aTuqlBnIa6agqgr12AFp6C EzLYzlUY772suahK8F1rZZz5WX5RbelvOgRtffBxmhnFZ7U3bmZZtDEc+LX6mV/d4NLJ sX02cjYjKZxAs3ZFeUDMeGEebT80IGGrtGvlGpW88WlvGscoNyKUoPRA1EUg+tCXpc6s DskQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=Jnif/0NMg0aeEcah82nrTBoEGi2KuieYH+LfZPYXFBE=; b=Pnn5OK9jRU0QNuNJboUte1j664BZaDEtV6HFclOZegCzSCE63YSo3FeSEmVWD+rGY1 K6GuDlTPVnbu7GMeNvHQEgbe6IWfxThajTz+AgBKqrRDG42RCy/SeQGOsnQaJncG+mGq hGvuE9oXL2kR1GDDpn8/DDlBwoDD90zkZqZmZa8ld1IeTn8dHghmgEd/Scn2Goe+Uq/m aBbb9o12r7TQAtt0dDydLlZDWyJF9awFQdNsyAhwHM+tdPGlanP6DeOaEM59ms3CD4f3 aJcd2iAWt7da9UqqQoZBuM5pcsk+co2XeQqYDCP7uIr+VXVkFJVtq4Mtd/VYho67OKad 6W9Q== X-Gm-Message-State: AOAM532D567ssyECk0ODTZCyoChU44HLll2sRn1WssO/WEsz2B7EQHsy QWpU09NIT0gqU2AlJ5gEwyvZqXW3Hbq5 X-Google-Smtp-Source: ABdhPJyWykqMLa09jI3ZYxwNtA+a7AHn2stPGV6XWbBnfIDJN88tDaF9BM0f32yrEgfWtxVJX4Gyd9cPVVKv X-Received: from bg.sfo.corp.google.com ([2620:15c:8:10:b047:e98d:2134:b4dd]) (user=bgeffon job=sendgmr) by 2002:a17:902:b908:b029:e6:3e0a:b3cc with SMTP id bf8-20020a170902b908b02900e63e0ab3ccmr7328154plb.68.1616523936041; Tue, 23 Mar 2021 11:25:36 -0700 (PDT) Date: Tue, 23 Mar 2021 11:25:19 -0700 In-Reply-To: <20210323182520.2712101-1-bgeffon@google.com> Message-Id: <20210323182520.2712101-3-bgeffon@google.com> Mime-Version: 1.0 References: <20210303175235.3308220-1-bgeffon@google.com> <20210323182520.2712101-1-bgeffon@google.com> X-Mailer: git-send-email 2.31.0.291.g576ba9dcdaf-goog Subject: [PATCH v5 3/3] selftests: Add a MREMAP_DONTUNMAP selftest for shmem From: Brian Geffon To: Andrew Morton Cc: Axel Rasmussen , Lokesh Gidra , Mike Rapoport , Peter Xu , Hugh Dickins , "Michael S . Tsirkin" , Brian Geffon , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andy Lutomirski , Vlastimil Babka , Andrea Arcangeli , Sonny Rao , Minchan Kim , "Kirill A . Shutemov" , Dmitry Safonov , Michael Kerrisk , Alejandro Colomar Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This test extends the current mremap tests to validate that the MREMAP_DONTUNMAP operation can be performed on shmem mappings. Signed-off-by: Brian Geffon --- tools/testing/selftests/vm/mremap_dontunmap.c | 52 +++++++++++++++++++ 1 file changed, 52 insertions(+) diff --git a/tools/testing/selftests/vm/mremap_dontunmap.c b/tools/testing/selftests/vm/mremap_dontunmap.c index 3a7b5ef0b0c6..f01dc4a85b0b 100644 --- a/tools/testing/selftests/vm/mremap_dontunmap.c +++ b/tools/testing/selftests/vm/mremap_dontunmap.c @@ -127,6 +127,57 @@ static void mremap_dontunmap_simple() "unable to unmap source mapping"); } +// This test validates that MREMAP_DONTUNMAP on a shared mapping works as expected. +static void mremap_dontunmap_simple_shmem() +{ + unsigned long num_pages = 5; + + int mem_fd = memfd_create("memfd", MFD_CLOEXEC); + BUG_ON(mem_fd < 0, "memfd_create"); + + BUG_ON(ftruncate(mem_fd, num_pages * page_size) < 0, + "ftruncate"); + + void *source_mapping = + mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE, + MAP_FILE | MAP_SHARED, mem_fd, 0); + BUG_ON(source_mapping == MAP_FAILED, "mmap"); + + BUG_ON(close(mem_fd) < 0, "close"); + + memset(source_mapping, 'a', num_pages * page_size); + + // Try to just move the whole mapping anywhere (not fixed). + void *dest_mapping = + mremap(source_mapping, num_pages * page_size, num_pages * page_size, + MREMAP_DONTUNMAP | MREMAP_MAYMOVE, NULL); + if (dest_mapping == MAP_FAILED && errno == EINVAL) { + // Old kernel which doesn't support MREMAP_DONTUNMAP on shmem. + BUG_ON(munmap(source_mapping, num_pages * page_size) == -1, + "unable to unmap source mapping"); + return; + } + + BUG_ON(dest_mapping == MAP_FAILED, "mremap"); + + // Validate that the pages have been moved, we know they were moved if + // the dest_mapping contains a's. + BUG_ON(check_region_contains_byte + (dest_mapping, num_pages * page_size, 'a') != 0, + "pages did not migrate"); + + // Because the region is backed by shmem, we will actually see the same + // memory at the source location still. + BUG_ON(check_region_contains_byte + (source_mapping, num_pages * page_size, 'a') != 0, + "source should have no ptes"); + + BUG_ON(munmap(dest_mapping, num_pages * page_size) == -1, + "unable to unmap destination mapping"); + BUG_ON(munmap(source_mapping, num_pages * page_size) == -1, + "unable to unmap source mapping"); +} + // This test validates MREMAP_DONTUNMAP will move page tables to a specific // destination using MREMAP_FIXED, also while validating that the source // remains intact. @@ -300,6 +351,7 @@ int main(void) BUG_ON(page_buffer == MAP_FAILED, "unable to mmap a page."); mremap_dontunmap_simple(); + mremap_dontunmap_simple_shmem(); mremap_dontunmap_simple_fixed(); mremap_dontunmap_partial_mapping(); mremap_dontunmap_partial_mapping_overwrite(); -- 2.31.0.291.g576ba9dcdaf-goog 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=-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=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 1C621C433C1 for ; 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Tsirkin" , Brian Geffon , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andy Lutomirski , Vlastimil Babka , Andrea Arcangeli , Sonny Rao , Minchan Kim , "Kirill A . Shutemov" , Dmitry Safonov , Michael Kerrisk , Alejandro Colomar Content-Type: text/plain; charset="UTF-8" X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: BC2C5A000848 X-Stat-Signature: 1r397r4reb8eet58tafthqr659frujpk Received-SPF: none (flex--bgeffon.bounces.google.com>: No applicable sender policy available) receiver=imf07; identity=mailfrom; envelope-from="<3oDJaYAcKCHcWbZaajibjjbgZ.Xjhgdips-hhfqVXf.jmb@flex--bgeffon.bounces.google.com>"; helo=mail-pf1-f202.google.com; client-ip=209.85.210.202 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616523936-202809 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: This test extends the current mremap tests to validate that the MREMAP_DONTUNMAP operation can be performed on shmem mappings. Signed-off-by: Brian Geffon --- tools/testing/selftests/vm/mremap_dontunmap.c | 52 +++++++++++++++++++ 1 file changed, 52 insertions(+) diff --git a/tools/testing/selftests/vm/mremap_dontunmap.c b/tools/testing/selftests/vm/mremap_dontunmap.c index 3a7b5ef0b0c6..f01dc4a85b0b 100644 --- a/tools/testing/selftests/vm/mremap_dontunmap.c +++ b/tools/testing/selftests/vm/mremap_dontunmap.c @@ -127,6 +127,57 @@ static void mremap_dontunmap_simple() "unable to unmap source mapping"); } +// This test validates that MREMAP_DONTUNMAP on a shared mapping works as expected. +static void mremap_dontunmap_simple_shmem() +{ + unsigned long num_pages = 5; + + int mem_fd = memfd_create("memfd", MFD_CLOEXEC); + BUG_ON(mem_fd < 0, "memfd_create"); + + BUG_ON(ftruncate(mem_fd, num_pages * page_size) < 0, + "ftruncate"); + + void *source_mapping = + mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE, + MAP_FILE | MAP_SHARED, mem_fd, 0); + BUG_ON(source_mapping == MAP_FAILED, "mmap"); + + BUG_ON(close(mem_fd) < 0, "close"); + + memset(source_mapping, 'a', num_pages * page_size); + + // Try to just move the whole mapping anywhere (not fixed). + void *dest_mapping = + mremap(source_mapping, num_pages * page_size, num_pages * page_size, + MREMAP_DONTUNMAP | MREMAP_MAYMOVE, NULL); + if (dest_mapping == MAP_FAILED && errno == EINVAL) { + // Old kernel which doesn't support MREMAP_DONTUNMAP on shmem. + BUG_ON(munmap(source_mapping, num_pages * page_size) == -1, + "unable to unmap source mapping"); + return; + } + + BUG_ON(dest_mapping == MAP_FAILED, "mremap"); + + // Validate that the pages have been moved, we know they were moved if + // the dest_mapping contains a's. + BUG_ON(check_region_contains_byte + (dest_mapping, num_pages * page_size, 'a') != 0, + "pages did not migrate"); + + // Because the region is backed by shmem, we will actually see the same + // memory at the source location still. + BUG_ON(check_region_contains_byte + (source_mapping, num_pages * page_size, 'a') != 0, + "source should have no ptes"); + + BUG_ON(munmap(dest_mapping, num_pages * page_size) == -1, + "unable to unmap destination mapping"); + BUG_ON(munmap(source_mapping, num_pages * page_size) == -1, + "unable to unmap source mapping"); +} + // This test validates MREMAP_DONTUNMAP will move page tables to a specific // destination using MREMAP_FIXED, also while validating that the source // remains intact. @@ -300,6 +351,7 @@ int main(void) BUG_ON(page_buffer == MAP_FAILED, "unable to mmap a page."); mremap_dontunmap_simple(); + mremap_dontunmap_simple_shmem(); mremap_dontunmap_simple_fixed(); mremap_dontunmap_partial_mapping(); mremap_dontunmap_partial_mapping_overwrite(); -- 2.31.0.291.g576ba9dcdaf-goog