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 6BFF2C433EF for ; Tue, 7 Dec 2021 02:47:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230204AbhLGCub (ORCPT ); Mon, 6 Dec 2021 21:50:31 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51100 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230123AbhLGCuZ (ORCPT ); Mon, 6 Dec 2021 21:50:25 -0500 Received: from mail-wr1-x42e.google.com (mail-wr1-x42e.google.com [IPv6:2a00:1450:4864:20::42e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 22CE3C061354 for ; Mon, 6 Dec 2021 18:46:56 -0800 (PST) Received: by mail-wr1-x42e.google.com with SMTP id a18so26413404wrn.6 for ; Mon, 06 Dec 2021 18:46:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:in-reply-to:references:from:date:subject:fcc :content-transfer-encoding:mime-version:to:cc; bh=4560Oo1asFqSCY7CyTBbvQRJTIDfLxJTwwZXXpZWrLw=; b=kyy2lXjzD7sEwSuY3kpu+mSZXAmvSoDI/YfbbIBsb9Xf1fhaMK7XQpLVyrPnI73FM4 nBxaa0wrmPByaagGVqwDOVQbnivTnxXSqGKPzNEnLvKrj6Q+b9OX4m2yOAoVvsf8xmwr hT6C+kfGj40EMcQZZExxk9bsBbRSqP2AF3b2MGlV9XMbtYZzIcOIfjquuYOnia+jG33+ 52pS+GmrhivFlJq/ZiyPCqUvIlKjtAj3WVN4dO3+ZAA/fEzZXeCsPSB7v3cYnEpqvJM+ cMWjXkpI+jKraBeyvM+K1HqxjvYpSEdyXaAu4+3cnwg3OO8rZdFnifShXKH+58FT9YHv dhwA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:in-reply-to:references:from:date :subject:fcc:content-transfer-encoding:mime-version:to:cc; bh=4560Oo1asFqSCY7CyTBbvQRJTIDfLxJTwwZXXpZWrLw=; b=3pTBjeTuiTT42i1KPwLGmYETfIo4FsHgu2IdArQYmgfb0XhYvnBinErslr5yBf6/Il aCItI0Q76nYHyZEU3S+QqWCwf7KAORpdyILTM9WqJeB+isaFUPsAc4iJG6p592J9uZgM /IXZbvzteoOSqK73aDrs4gGvvn2vcqbYLMiSXtbgK1kIJMbgNTdaRcqLCBjinAQs07j4 BNuvpkpi5ShDbCGHGDzXtXGpU4+wR4pE0axq2VCZKqhFfnsJX/sf48T7zoeEj53wvIU5 uFTCr9Y4ALP7+rMSLn6EWEg/YL14pucjXQDgVKpXugn5jbG3ubtzNPLcig+WXzzduLnl euLA== X-Gm-Message-State: AOAM5329YuBANGVHiLZyl+s91FkE9jihEzuOx0/xE5V0OeYDyNmIQf6X zg2r9BK0teJARYLpBZSc3qQzliClueQ= X-Google-Smtp-Source: ABdhPJy6IiieRg1elPa81HnmXBFOYp18Nw9hct1OpC4DrN0fi+tvqnzQHaZcpaqjIxJjWm62FETNbw== X-Received: by 2002:a5d:6211:: with SMTP id y17mr48308567wru.97.1638845214516; Mon, 06 Dec 2021 18:46:54 -0800 (PST) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id d8sm12859499wrm.76.2021.12.06.18.46.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 06 Dec 2021 18:46:54 -0800 (PST) Message-Id: <86e39b8f8d16100b33346d16e7f722064ab9615c.1638845211.git.gitgitgadget@gmail.com> In-Reply-To: References: From: "Neeraj Singh via GitGitGadget" Date: Tue, 07 Dec 2021 02:46:51 +0000 Subject: [PATCH v2 3/3] core.fsync: new option to harden the index Fcc: Sent Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit MIME-Version: 1.0 To: git@vger.kernel.org Cc: rsbecker@nexbridge.com, bagasdotme@gmail.com, newren@gmail.com, avarab@gmail.com, nksingh85@gmail.com, ps@pks.im, "Neeraj K. Singh" , Neeraj Singh Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org From: Neeraj Singh This commit introduces the new ability for the user to harden the index. In the event of a system crash, the index must be durable for the user to actually find a file that has been added to the repo and then deleted from the working tree. We use the presence of the COMMIT_LOCK flag and absence of the alternate_index_output as a proxy for determining whether we're updating the persistent index of the repo or some temporary index. We don't sync these temporary indexes. Signed-off-by: Neeraj Singh --- Documentation/config/core.txt | 1 + cache.h | 4 +++- config.c | 1 + read-cache.c | 19 +++++++++++++------ 4 files changed, 18 insertions(+), 7 deletions(-) diff --git a/Documentation/config/core.txt b/Documentation/config/core.txt index 4f1747ec871..8e5b7a795ab 100644 --- a/Documentation/config/core.txt +++ b/Documentation/config/core.txt @@ -561,6 +561,7 @@ core.fsync:: * `pack` hardens objects added to the repo in packfile form. * `pack-metadata` hardens packfile bitmaps and indexes. * `commit-graph` hardens the commit graph file. +* `index` hardens the index when it is modified. * `objects` is an aggregate option that includes `loose-objects`, `pack`, `pack-metadata`, and `commit-graph`. * `default` is an aggregate option that is equivalent to `objects,-loose-object` diff --git a/cache.h b/cache.h index d83fbaf2619..4dc26d7b2c9 100644 --- a/cache.h +++ b/cache.h @@ -996,6 +996,7 @@ enum fsync_component { FSYNC_COMPONENT_PACK = 1 << 1, FSYNC_COMPONENT_PACK_METADATA = 1 << 2, FSYNC_COMPONENT_COMMIT_GRAPH = 1 << 3, + FSYNC_COMPONENT_INDEX = 1 << 4, }; #define FSYNC_COMPONENTS_DEFAULT (FSYNC_COMPONENT_PACK | \ @@ -1010,7 +1011,8 @@ enum fsync_component { #define FSYNC_COMPONENTS_ALL (FSYNC_COMPONENT_LOOSE_OBJECT | \ FSYNC_COMPONENT_PACK | \ FSYNC_COMPONENT_PACK_METADATA | \ - FSYNC_COMPONENT_COMMIT_GRAPH) + FSYNC_COMPONENT_COMMIT_GRAPH | \ + FSYNC_COMPONENT_INDEX) /* diff --git a/config.c b/config.c index 29c867aab03..17039fa9c10 100644 --- a/config.c +++ b/config.c @@ -1221,6 +1221,7 @@ static const struct fsync_component_entry { { "pack", FSYNC_COMPONENT_PACK }, { "pack-metadata", FSYNC_COMPONENT_PACK_METADATA }, { "commit-graph", FSYNC_COMPONENT_COMMIT_GRAPH }, + { "index", FSYNC_COMPONENT_INDEX }, { "objects", FSYNC_COMPONENTS_OBJECTS }, { "default", FSYNC_COMPONENTS_DEFAULT }, { "all", FSYNC_COMPONENTS_ALL }, diff --git a/read-cache.c b/read-cache.c index f3539681f49..783cb3ea5db 100644 --- a/read-cache.c +++ b/read-cache.c @@ -2816,7 +2816,7 @@ static int record_ieot(void) * rely on it. */ static int do_write_index(struct index_state *istate, struct tempfile *tempfile, - int strip_extensions) + int strip_extensions, unsigned flags) { uint64_t start = getnanotime(); struct hashfile *f; @@ -2830,6 +2830,7 @@ static int do_write_index(struct index_state *istate, struct tempfile *tempfile, struct strbuf previous_name_buf = STRBUF_INIT, *previous_name; int drop_cache_tree = istate->drop_cache_tree; off_t offset; + int csum_fsync_flag; int ieot_entries = 1; struct index_entry_offset_table *ieot = NULL; int nr, nr_threads; @@ -3060,7 +3061,13 @@ static int do_write_index(struct index_state *istate, struct tempfile *tempfile, return -1; } - finalize_hashfile(f, istate->oid.hash, FSYNC_COMPONENT_NONE, CSUM_HASH_IN_STREAM); + csum_fsync_flag = 0; + if (!alternate_index_output && (flags & COMMIT_LOCK)) + csum_fsync_flag = CSUM_FSYNC; + + finalize_hashfile(f, istate->oid.hash, FSYNC_COMPONENT_INDEX, + CSUM_HASH_IN_STREAM | csum_fsync_flag); + if (close_tempfile_gently(tempfile)) { error(_("could not close '%s'"), get_tempfile_path(tempfile)); return -1; @@ -3115,7 +3122,7 @@ static int do_write_locked_index(struct index_state *istate, struct lock_file *l */ trace2_region_enter_printf("index", "do_write_index", the_repository, "%s", get_lock_file_path(lock)); - ret = do_write_index(istate, lock->tempfile, 0); + ret = do_write_index(istate, lock->tempfile, 0, flags); trace2_region_leave_printf("index", "do_write_index", the_repository, "%s", get_lock_file_path(lock)); @@ -3209,7 +3216,7 @@ static int clean_shared_index_files(const char *current_hex) } static int write_shared_index(struct index_state *istate, - struct tempfile **temp) + struct tempfile **temp, unsigned flags) { struct split_index *si = istate->split_index; int ret, was_full = !istate->sparse_index; @@ -3219,7 +3226,7 @@ static int write_shared_index(struct index_state *istate, trace2_region_enter_printf("index", "shared/do_write_index", the_repository, "%s", get_tempfile_path(*temp)); - ret = do_write_index(si->base, *temp, 1); + ret = do_write_index(si->base, *temp, 1, flags); trace2_region_leave_printf("index", "shared/do_write_index", the_repository, "%s", get_tempfile_path(*temp)); @@ -3328,7 +3335,7 @@ int write_locked_index(struct index_state *istate, struct lock_file *lock, ret = do_write_locked_index(istate, lock, flags); goto out; } - ret = write_shared_index(istate, &temp); + ret = write_shared_index(istate, &temp, flags); saved_errno = errno; if (is_tempfile_active(temp)) -- gitgitgadget