From patchwork Thu Oct 29 23:57:48 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Boris Burkov X-Patchwork-Id: 11867911 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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 52DFDC4741F for ; Thu, 29 Oct 2020 23:58:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A2AE92076A for ; Thu, 29 Oct 2020 23:58:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=bur.io header.i=@bur.io header.b="OwInHmBD"; dkim=temperror (0-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="F+XiRsE6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725897AbgJ2X6G (ORCPT ); Thu, 29 Oct 2020 19:58:06 -0400 Received: from out1-smtp.messagingengine.com ([66.111.4.25]:40221 "EHLO out1-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725372AbgJ2X6G (ORCPT ); Thu, 29 Oct 2020 19:58:06 -0400 Received: from compute2.internal (compute2.nyi.internal [10.202.2.42]) by mailout.nyi.internal (Postfix) with ESMTP id B0C885C00AE; Thu, 29 Oct 2020 19:58:04 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute2.internal (MEProxy); Thu, 29 Oct 2020 19:58:04 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bur.io; h=from :to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; s=fm2; bh=ZuO/DuznAXTj6dUlvuHz0gK2qR fZJCIo5KHjwpqzhoE=; b=OwInHmBDt8339JjLXaLL0gdlrXq8t0jkb59b8CXBfV LSM16e5Eq/yWpBcTSHr5qrIeBotGVftuBSqWfQ0x+3KKY1Cvh0XO3Li2ColBHbPU iNXivTfzVRixWiW0lKfr5xFEtXPKLJQvXw65YqZxD93W13cAtnEtr10ojmZlf23A GSbS7FhdTJy8hxmgav1+xBX7rr4PzAgJ+5jvaH8ueyBn2GUMjsDLYkh5q55WnL94 fu+pC9gybVqFR6WReUMpOW8ozTFqp5u38I9bmwE+gb0RPxi729F9IU0vRwcQUIER e/khU6OoKj6GDU56/XWkslKD4a3OhPtWIWjkpfDYE42A== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=content-transfer-encoding:date:from :in-reply-to:message-id:mime-version:references:subject:to :x-me-proxy:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s= fm1; bh=ZuO/DuznAXTj6dUlvuHz0gK2qRfZJCIo5KHjwpqzhoE=; b=F+XiRsE6 G2Ch3ifvx1WK1sCNFoW2OreKLx502aD0FnR6bT78EPj3BP111lFj75PancZxEQMM f9gfTsTwpOpyGCvsy4EmGDwFVWbR2WtwQjBzSG+Lxnd40gb3tOAcjMD4NGu6Nen2 heRczwudLXyFgpjYo+UAtELNMCAI4fQ/3oS83tcqYFEnUiImoWz8TFwNejD5zdv0 Bx70zMp1fAGMVojqcfxwInJFGNcsME3aQzHVMNh3N0xe+9IJhyHUabxgLDhtqV9O QACdvr2Ahbznv6b320UjphRgZqOYjCHsIARkJIhCxvEqyHqEYgaiIsswCeUKTHxM PfGLm0UgfUPRJg== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedujedrleeggdduiecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecunecujfgurhephffvufffkffojghfggfgsedtkeertd ertddtnecuhfhrohhmpeeuohhrihhsuceuuhhrkhhovhcuoegsohhrihhssegsuhhrrdhi oheqnecuggftrfgrthhtvghrnhepieeuffeuvdeiueejhfehiefgkeevudejjeejffevvd ehtddufeeihfekgeeuheelnecukfhppeduieefrdduudegrddufedvrdefnecuvehluhhs thgvrhfuihiivgeptdenucfrrghrrghmpehmrghilhhfrhhomhepsghorhhishessghurh drihho X-ME-Proxy: Received: from localhost (unknown [163.114.132.3]) by mail.messagingengine.com (Postfix) with ESMTPA id EF4103064682; Thu, 29 Oct 2020 19:58:03 -0400 (EDT) From: Boris Burkov To: linux-btrfs@vger.kernel.org, kernel-team@fb.com Subject: [PATCH v6 01/10] btrfs: lift rw mount setup from mount and remount Date: Thu, 29 Oct 2020 16:57:48 -0700 Message-Id: <30c4efc1374a7e894e25fafb2de5781d3093519f.1604015464.git.boris@bur.io> X-Mailer: git-send-email 2.24.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org Mounting rw and remounting from ro to rw naturally share invariants and functionality which result in a correctly setup rw filesystem. Luckily, there is even a strong unity in the code which implements them. In mount's open_ctree, these operations mostly happen after an early return for ro file systems, and in remount, they happen in a section devoted to remounting ro->rw, after some remount specific validation passes. However, there are unfortunately a few differences. There are small deviations in the order of some of the operations, remount does not cleanup orphan inodes in root_tree or fs_tree, remount does not create the free space tree, and remount does not handle "one-shot" mount options like clear_cache and uuid tree rescan. Since we want to add building the free space tree to remount, and since it is possible to leak orphans on a filesystem mounted as ro then remounted rw (common for the root filesystem when booting), we would benefit from unifying the logic between the two codepaths. This patch only lifts the existing common functionality, and leaves a natural path for fixing the discrepancies. Signed-off-by: Boris Burkov --- fs/btrfs/disk-io.c | 91 ++++++++++++++++++++++++++-------------------- fs/btrfs/disk-io.h | 1 + fs/btrfs/super.c | 37 +++---------------- 3 files changed, 59 insertions(+), 70 deletions(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 601a7ab2adb4..b741a711bad5 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -2894,6 +2894,53 @@ static int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info) return 0; } +/* + * Mounting logic specific to read-write file systems. Shared by open_ctree + * and btrfs_remount when remounting from read-only to read-write. + */ +int btrfs_mount_rw(struct btrfs_fs_info *fs_info) +{ + int ret; + + ret = btrfs_cleanup_fs_roots(fs_info); + if (ret) + goto out; + + mutex_lock(&fs_info->cleaner_mutex); + ret = btrfs_recover_relocation(fs_info->tree_root); + mutex_unlock(&fs_info->cleaner_mutex); + if (ret < 0) { + btrfs_warn(fs_info, "failed to recover relocation: %d", ret); + goto out; + } + + ret = btrfs_resume_balance_async(fs_info); + if (ret) + goto out; + + ret = btrfs_resume_dev_replace_async(fs_info); + if (ret) { + btrfs_warn(fs_info, "failed to resume dev_replace"); + goto out; + } + + btrfs_qgroup_rescan_resume(fs_info); + + if (!fs_info->uuid_root) { + btrfs_info(fs_info, "creating UUID tree"); + ret = btrfs_create_uuid_tree(fs_info); + if (ret) { + btrfs_warn(fs_info, + "failed to create the UUID tree %d", + ret); + goto out; + } + } + +out: + return ret; +} + int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_devices, char *options) { @@ -3298,22 +3345,6 @@ int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_device if (ret) goto fail_qgroup; - if (!sb_rdonly(sb)) { - ret = btrfs_cleanup_fs_roots(fs_info); - if (ret) - goto fail_qgroup; - - mutex_lock(&fs_info->cleaner_mutex); - ret = btrfs_recover_relocation(tree_root); - mutex_unlock(&fs_info->cleaner_mutex); - if (ret < 0) { - btrfs_warn(fs_info, "failed to recover relocation: %d", - ret); - err = -EINVAL; - goto fail_qgroup; - } - } - fs_info->fs_root = btrfs_get_fs_root(fs_info, BTRFS_FS_TREE_OBJECTID, true); if (IS_ERR(fs_info->fs_root)) { err = PTR_ERR(fs_info->fs_root); @@ -3366,35 +3397,17 @@ int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_device } up_read(&fs_info->cleanup_work_sem); - ret = btrfs_resume_balance_async(fs_info); - if (ret) { - btrfs_warn(fs_info, "failed to resume balance: %d", ret); - close_ctree(fs_info); - return ret; - } - - ret = btrfs_resume_dev_replace_async(fs_info); + ret = btrfs_mount_rw(fs_info); if (ret) { - btrfs_warn(fs_info, "failed to resume device replace: %d", ret); close_ctree(fs_info); return ret; } - - btrfs_qgroup_rescan_resume(fs_info); btrfs_discard_resume(fs_info); - if (!fs_info->uuid_root) { - btrfs_info(fs_info, "creating UUID tree"); - ret = btrfs_create_uuid_tree(fs_info); - if (ret) { - btrfs_warn(fs_info, - "failed to create the UUID tree: %d", ret); - close_ctree(fs_info); - return ret; - } - } else if (btrfs_test_opt(fs_info, RESCAN_UUID_TREE) || - fs_info->generation != - btrfs_super_uuid_tree_generation(disk_super)) { + if (fs_info->uuid_root && + (btrfs_test_opt(fs_info, RESCAN_UUID_TREE) || + fs_info->generation != + btrfs_super_uuid_tree_generation(disk_super))) { btrfs_info(fs_info, "checking UUID tree"); ret = btrfs_check_uuid_tree(fs_info); if (ret) { diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h index 182540bdcea0..a4e6cdbe3a48 100644 --- a/fs/btrfs/disk-io.h +++ b/fs/btrfs/disk-io.h @@ -50,6 +50,7 @@ struct extent_buffer *btrfs_find_create_tree_block( struct btrfs_fs_info *fs_info, u64 bytenr); void btrfs_clean_tree_block(struct extent_buffer *buf); +int btrfs_mount_rw(struct btrfs_fs_info *fs_info); int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_devices, char *options); diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 1ffa50bae1dd..22299fc13b6d 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1880,7 +1880,6 @@ static inline void btrfs_remount_cleanup(struct btrfs_fs_info *fs_info, static int btrfs_remount(struct super_block *sb, int *flags, char *data) { struct btrfs_fs_info *fs_info = btrfs_sb(sb); - struct btrfs_root *root = fs_info->tree_root; unsigned old_flags = sb->s_flags; unsigned long old_opts = fs_info->mount_opt; unsigned long old_compress_type = fs_info->compress_type; @@ -1973,39 +1972,15 @@ static int btrfs_remount(struct super_block *sb, int *flags, char *data) goto restore; } - ret = btrfs_cleanup_fs_roots(fs_info); - if (ret) - goto restore; - - /* recover relocation */ - mutex_lock(&fs_info->cleaner_mutex); - ret = btrfs_recover_relocation(root); - mutex_unlock(&fs_info->cleaner_mutex); - if (ret) - goto restore; - - ret = btrfs_resume_balance_async(fs_info); + /* + * NOTE: when remounting with a change that does writes, don't + * put it anywhere above this point, as we are not sure to be + * safe to write until we pass the above checks. + */ + ret = btrfs_mount_rw(fs_info); if (ret) goto restore; - ret = btrfs_resume_dev_replace_async(fs_info); - if (ret) { - btrfs_warn(fs_info, "failed to resume dev_replace"); - goto restore; - } - - btrfs_qgroup_rescan_resume(fs_info); - - if (!fs_info->uuid_root) { - btrfs_info(fs_info, "creating UUID tree"); - ret = btrfs_create_uuid_tree(fs_info); - if (ret) { - btrfs_warn(fs_info, - "failed to create the UUID tree %d", - ret); - goto restore; - } - } sb->s_flags &= ~SB_RDONLY; set_bit(BTRFS_FS_OPEN, &fs_info->flags);