From patchwork Thu Feb 25 12:58:28 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nikolay Borisov X-Patchwork-Id: 12104081 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=-18.8 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 E5728C433DB for ; Thu, 25 Feb 2021 12:59:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8803964EFA for ; Thu, 25 Feb 2021 12:59:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231978AbhBYM7R (ORCPT ); Thu, 25 Feb 2021 07:59:17 -0500 Received: from mx2.suse.de ([195.135.220.15]:46862 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230498AbhBYM7Q (ORCPT ); Thu, 25 Feb 2021 07:59:16 -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=1614257910; 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=KUumbRx+Xsj9WgRCcQCui1lkxvQGPEvjij5G4fq6J5g=; b=SYLj1XpodG8Uaqlfxipzytvfjp/uihU8Ev6eLVhTVhI1CBGfwOKRhoVUXZalVTPyUjXvxX aA/qBSdOTbFmwWGP6fnVZD/p0Vs2vl8CxpXj/aI4GzNqHRCUjmwnRbuhMCfbMyOEM3I6Ub 6rCh6hnpg8OQdqIBR1YAshI6bL5NuqE= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 0E0F4AF6F; Thu, 25 Feb 2021 12:58:30 +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: Thu, 25 Feb 2021 14:58:28 +0200 Message-Id: <20210225125828.1601531-1-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(-) diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index af0253473508..4530952c3356 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; }