From patchwork Tue Mar 2 10:45:29 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nikolay Borisov X-Patchwork-Id: 12112659 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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,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 F2922C28D13 for ; Wed, 3 Mar 2021 02:02:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4663C64EC9 for ; Wed, 3 Mar 2021 02:02:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243342AbhCCB6Z (ORCPT ); Tue, 2 Mar 2021 20:58:25 -0500 Received: from mx2.suse.de ([195.135.220.15]:40620 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1383065AbhCBKqR (ORCPT ); Tue, 2 Mar 2021 05:46:17 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1614681930; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=gMhegv0wURC2UGRjyU5EPTwJONbebSYq4WXPIKrC3ec=; b=NEAPSJkugybimN6OXpVf9gb/isEeU8uUP66ePPsNGFQ5Kx//glmxZoR3SjoFkH2XJJXQJ7 R4JbMdzTkl5LJIeCIllgcSNNT/w21cqd/x+uTx93SvduckOS7JAdLva5mciK0X/i3Y3PNQ tC2FtehmgTkVDLfykvk+vhr4+ksKOCA= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 9CCF5AD2B; Tue, 2 Mar 2021 10:45:30 +0000 (UTC) From: Nikolay Borisov To: linux-btrfs@vger.kernel.org Cc: Nikolay Borisov Subject: [PATCH] btrfs: Refactor error handling in btrfs_zero_range Date: Tue, 2 Mar 2021 12:45:29 +0200 Message-Id: <20210302104529.2319101-1-nborisov@suse.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org The major complexity when it comes to error handling in btrfs_zero_range stems from the code executed under the 'reserve_space' label. Rather than it having an effect on the whole of btrfs_zero_range refactor it so that error handling specific to the functions called in this branch is contained only within the branch itself. This obviates the need for having the 'space_reserved' local flag since btrfs_free_reserved_data_space is called from the 2 error branches it's needed. Furthermore, this rids the code from the out label and enables converting most 'goto out' statements to simiple 'return ret' making the function easier to read. Signed-off-by: Nikolay Borisov --- fs/btrfs/file.c | 70 +++++++++++++++++++++++-------------------------- 1 file changed, 33 insertions(+), 37 deletions(-) -- 2.25.1 diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index d0cb513d0019..de86372dba48 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -3113,23 +3113,19 @@ static int btrfs_zero_range(struct inode *inode, { struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info; struct extent_map *em; - struct extent_changeset *data_reserved = NULL; int ret; u64 alloc_hint = 0; const u64 sectorsize = btrfs_inode_sectorsize(BTRFS_I(inode)); u64 alloc_start = round_down(offset, sectorsize); u64 alloc_end = round_up(offset + len, sectorsize); u64 bytes_to_reserve = 0; - bool space_reserved = false; inode_dio_wait(inode); em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, alloc_start, alloc_end - alloc_start); - if (IS_ERR(em)) { - ret = PTR_ERR(em); - goto out; - } + if (IS_ERR(em)) + return PTR_ERR(em); /* * Avoid hole punching and extent allocation for some cases. More cases @@ -3150,9 +3146,8 @@ static int btrfs_zero_range(struct inode *inode, * needed. */ free_extent_map(em); - ret = btrfs_fallocate_update_isize(inode, offset + len, - mode); - goto out; + return btrfs_fallocate_update_isize(inode, offset + len, + mode); } /* * Part of the range is already a prealloc extent, so operate @@ -3170,26 +3165,22 @@ static int btrfs_zero_range(struct inode *inode, BTRFS_BYTES_TO_BLKS(fs_info, offset + len - 1)) { em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, alloc_start, sectorsize); - if (IS_ERR(em)) { - ret = PTR_ERR(em); - goto out; - } + if (IS_ERR(em)) + return PTR_ERR(em); if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) { free_extent_map(em); - ret = btrfs_fallocate_update_isize(inode, offset + len, - mode); - goto out; + return btrfs_fallocate_update_isize(inode, + offset + len, mode); } if (len < sectorsize && em->block_start != EXTENT_MAP_HOLE) { free_extent_map(em); ret = btrfs_truncate_block(BTRFS_I(inode), offset, len, 0); - if (!ret) - ret = btrfs_fallocate_update_isize(inode, - offset + len, - mode); - return ret; + if (ret) + return ret; + return btrfs_fallocate_update_isize(inode, + offset + len, mode); } free_extent_map(em); alloc_start = round_down(offset, sectorsize); @@ -3210,14 +3201,14 @@ static int btrfs_zero_range(struct inode *inode, ret = btrfs_zero_range_check_range_boundary(BTRFS_I(inode), offset); if (ret < 0) - goto out; + return ret; if (ret == RANGE_BOUNDARY_HOLE) { alloc_start = round_down(offset, sectorsize); ret = 0; } else if (ret == RANGE_BOUNDARY_WRITTEN_EXTENT) { ret = btrfs_truncate_block(BTRFS_I(inode), offset, 0, 0); if (ret) - goto out; + return ret; } else { ret = 0; } @@ -3227,7 +3218,7 @@ static int btrfs_zero_range(struct inode *inode, ret = btrfs_zero_range_check_range_boundary(BTRFS_I(inode), offset + len); if (ret < 0) - goto out; + return ret; if (ret == RANGE_BOUNDARY_HOLE) { alloc_end = round_up(offset + len, sectorsize); ret = 0; @@ -3235,7 +3226,7 @@ static int btrfs_zero_range(struct inode *inode, ret = btrfs_truncate_block(BTRFS_I(inode), offset + len, 0, 1); if (ret) - goto out; + return ret; } else { ret = 0; } @@ -3243,6 +3234,7 @@ static int btrfs_zero_range(struct inode *inode, reserve_space: if (alloc_start < alloc_end) { + struct extent_changeset *data_reserved = NULL; struct extent_state *cached_state = NULL; const u64 lockstart = alloc_start; const u64 lockend = alloc_end - 1; @@ -3251,18 +3243,27 @@ static int btrfs_zero_range(struct inode *inode, ret = btrfs_alloc_data_chunk_ondemand(BTRFS_I(inode), bytes_to_reserve); if (ret < 0) - goto out; - space_reserved = true; + return ret; ret = btrfs_punch_hole_lock_range(inode, lockstart, lockend, &cached_state); - if (ret) - goto out; + if (ret) { + btrfs_free_reserved_data_space(BTRFS_I(inode), + data_reserved, + alloc_start, + bytes_to_reserve); + return ret; + } ret = btrfs_qgroup_reserve_data(BTRFS_I(inode), &data_reserved, alloc_start, bytes_to_reserve); if (ret) { + btrfs_free_reserved_data_space(BTRFS_I(inode), + data_reserved, + alloc_start, + bytes_to_reserve); unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend, &cached_state); - goto out; + extent_changeset_free(data_reserved); + return ret; } ret = btrfs_prealloc_file_range(inode, mode, alloc_start, alloc_end - alloc_start, @@ -3272,16 +3273,11 @@ static int btrfs_zero_range(struct inode *inode, lockend, &cached_state); /* btrfs_prealloc_file_range releases reserved space on error */ if (ret) { - space_reserved = false; - goto out; + extent_changeset_free(data_reserved); + return ret; } } ret = btrfs_fallocate_update_isize(inode, offset + len, mode); - out: - if (ret && space_reserved) - btrfs_free_reserved_data_space(BTRFS_I(inode), data_reserved, - alloc_start, bytes_to_reserve); - extent_changeset_free(data_reserved); return ret; }